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Sample records for metodo wienner-levinson multicanal

  1. La gestión de la abundancia : tiempo de consumo y uso del mando a distancia en la televisión multicanal

    OpenAIRE

    Garitaonandia Garnacho, Carmelo

    2000-01-01

    Este artículo se basa en un trabajo cuantitativo de entrevistas personales realizado a más de 300 personas abonadas a un servicio de televisión multicanal en España: Canal Satélite Digital, Vía Digital y operadores de cable. Entre sus resultados más importantes destaca que el consumo en tiempo de televisión es algo menor en los hogares de televisión multicanal que generalista y que, por otra parte, el uso del mando a distancia en la televisión multicanal de pago se orienta sobre todo al chequ...

  2. Qualitative analysis of the Dix-Hallpike maneuver in multi-canal BPPV using a biomechanical model: Introduction of an expanded Dix-Hallpike maneuver for enhanced diagnosis of multi-canal BPPV

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    Henri Traboulsi

    2017-09-01

    Conclusion: The Dix–Hallpike maneuver may cause simultaneous movement of otoliths present in multiple canals and create an obstacle to accurate diagnosis in multi-canal BPPV. An expanded Dix-Hallpike maneuver is described which adds intermediate steps with the head positioned to the right and left in the horizontal position before head-hanging. This expanded maneuver has helped to isolate affected semi-circular canals for individual assessment in multiple canal BPPV.

  3. El consumidor autoconfiado: Análisis metacognitivo del comportamiento multicanal de búsqueda de información

    OpenAIRE

    Orús Sanclemente, Carlos; Flavián Blanco, Carlos; Gurrea Sarasa, Raquel

    2012-01-01

    El proceso de decisión de compra multicanal, basado en una búsqueda intensiva de información en Internet y una posterior visita al establecimiento físico, representa un comportamiento muy extendido entre la población española con acceso a Internet. En este sentido, las características del medio y del propio individuo podrían ayudarnos a entender este comportamiento. Por un lado, Internet ofrece grandes cantidades de información de manera conveniente, inmediata y a bajo coste. Sin embargo, el ...

  4. Evaluación de la Función Neuromuscular del Antebrazo durante contracciones isométricas mediante Electromiografía de Superficie Multicanal

    OpenAIRE

    Mónica Rojas-Martínez; Michelle García; Joan Francesc Alonso; Jesús Marín; Miguel Ángel Mañanas

    2011-01-01

    Resumen: Desarrollo de un protocolo experimental con ejercicios de flexión isométrica de los dedos y muñeca asociado a lesiones de esfuerzo repetitivo, y validación de la electromiografía de superficie multicanal como técnica no invasiva en la monitorización de procesos de rehabilitación, por ejemplo, de la mialgia muscular en músicos pianistas. El análisis de los patrones de activación de tres músculos extensores y un flexor del antebrazo en un grupo control ha permitido obtener resultados r...

  5. Annihilation probability density and other applications of the Schwinger multichannel method to the positron and electron scattering; Densidade de probabilidade de aniquilacao e outras aplicacoes do metodo multicanal de Schwinger ao espalhamento de positrons e eletrons

    Energy Technology Data Exchange (ETDEWEB)

    Varella, Marcio Teixeira do Nascimento

    2001-12-15

    We have calculated annihilation probability densities (APD) for positron collisions against He atom and H{sub 2} molecule. It was found that direct annihilation prevails at low energies, while annihilation following virtual positronium (Ps) formation is the dominant mechanism at higher energies. In room-temperature collisions (10{sup -2} eV) the APD spread over a considerable extension, being quite similar to the electronic densities of the targets. The capture of the positron in an electronic Feshbach resonance strongly enhanced the annihilation rate in e{sup +}-H{sub 2} collisions. We also discuss strategies to improve the calculation of the annihilation parameter (Z{sub eff} ), after debugging the computational codes of the Schwinger Multichannel Method (SMC). Finally, we consider the inclusion of the Ps formation channel in the SMC and show that effective configurations (pseudo eigenstates of the Hamiltonian of the collision ) are able to significantly reduce the computational effort in positron scattering calculations. Cross sections for electron scattering by polyatomic molecules were obtained in three different approximations: static-exchange (SE); tatic-exchange-plus-polarization (SEP); and multichannel coupling. The calculations for polar targets were improved through the rotational resolution of scattering amplitudes in which the SMC was combined with the first Born approximation (FBA). In general, elastic cross sections (SE and SEP approximations) showed good agreement with available experimental data for several targets. Multichannel calculations for e{sup -} -H{sub 2}O scattering, on the other hand, presented spurious structures at the electronic excitation thresholds (author)

  6. Adaptación española de la versión reducida multicanal del Perfil de Sensibilidad No Verbal (MiniPONS

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    Francisco Martínez-Sánchez

    2013-05-01

    Full Text Available En este trabajo se presenta la adaptación española de la versión reducida multicanal del Perfil de Sensibilidad No Verbal (MiniPONS (Bänziger, Scherer, Hall y Rosenthal, 2011. Esta escala evalúa las diferencias individuales en la habilidad para reconocer emociones, actitudes interpersonales y comunicación de intenciones por canales no verbales. Esta versión multicanal reducida está compuesta por 64 estímulos no verbales de vídeo y/o audio que representan a una mujer en blanco y negro. El principal objetivo de este estudio es analizar las propiedades psicométricas del MiniPONS empleando para ello una amplia muestra de participantes (N = 1154 de entre 18 a 60 años, también se examinaron las diferencias en la sensibilidad no verbal en función del sexo y la edad. Se presentan los valores normativos, la fiabilidad y validez en tres estudios con 168, 254 y 1154 estudiantes universitarios. Los resultados muestran que las mujeres obtienen mejores puntuaciones en todas las condiciones estimulares, éstas no sólo procesan más eficientemente información emocional no verbal por canales unisensoriales (rostro, cuerpo, voz, si no que también la integran mejor. Los resultados indican que la versión española del MiniPONS presenta unas propiedades psicométricas similares a la escala original, mostrando moderada consistencia interna y fiabilidad test-retest, así como también una razonable validez convergente obtenida en las correlaciones con otras pruebas que evalúan la capacidad de reconocimiento emocional. Se concluye que la versión española del MiniPONS es un instrumento que evalúa adecuadamente la sensibilidad no verbal. Se discuten las limitaciones y potencial utilidad de la escala.

  7. Evaluación de la Función Neuromuscular del Antebrazo durante contracciones isométricas mediante Electromiografía de Superficie Multicanal

    Directory of Open Access Journals (Sweden)

    Mónica Rojas-Martínez

    2011-04-01

    Full Text Available Resumen: Desarrollo de un protocolo experimental con ejercicios de flexión isométrica de los dedos y muñeca asociado a lesiones de esfuerzo repetitivo, y validación de la electromiografía de superficie multicanal como técnica no invasiva en la monitorización de procesos de rehabilitación, por ejemplo, de la mialgia muscular en músicos pianistas. El análisis de los patrones de activación de tres músculos extensores y un flexor del antebrazo en un grupo control ha permitido obtener resultados repetitivos y reproducibles, detectando fatiga en el músculo flexor y en un extensor durante los ejercicios de resistencia. La detección de potenciales de acción propagándose con una estimación de la velocidad de conducción dentro del rango fisiológico refrenda los resultados de los patrones musculares obtenidos. Palabras clave: bioingeniería, electromiografía, lesión muscular, procesado de señal, rehabilitación

  8. Scienza e conoscenza: sul valore del metodo scientifico

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    Riccardo Luciano Appolloni

    2014-05-01

    Full Text Available L’antico problema di riconoscere una forma di conoscenza oggettivae fondata è ancora vivo; in questo scritto cercheremo di capire se la scienza moderna possa essere una forma di conoscenza tale e, quindi, privilegiata. A tal fine ci serviremo del pensiero di alcuni epistemologi e scienziati. In particolare, nel trattare il problema del valore epistemologico del metodo scientifico, non potremo esimerci dal fare i conti con l’anarchismo metodologico di Paul K. Feyerabend, verso il quale l’esito del presente articolo sarà fondamentalmente critico. A partire dai fecondi spunti di questo filosofo, tenteremo dapprima di analizzare i caratteri distintivi della scienza e del suo metodo rispetto ad altre forme di sapere; quindi, cercheremo di individuare alcuni limiti della conoscenza razionale.

  9. Resultados auditivos com o implante coclear multicanal em pacientes submetidos a cirurgia no Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo Auditory results with multicanal cochlear implant in patients submitted to cochlear implant surgery at University of São Paulo Medical School - Hospital das Clínicas

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    Ricardo Ferreira Bento

    2004-10-01

    Full Text Available A surdez profunda é uma deficiência que afeta a personalidade, o relacionamento e todo o estilo de vida do paciente. Incapacita os indivíduos de escutarem sons ambientes como sirenes e alarmes que constituem alerta em situações da vida diária e não permite a modulação vocal, tornando a voz esteticamente ruim. A prótese auditiva convencional é eficiente no tratamento de grande parte das deficiências auditivas, porém existem pacientes que não conseguem obter discriminação de palavras e sentenças mesmo com uma prótese auditiva potente. O implante coclear é a alternativa atual para estes pacientes. OBJETIVO: Avaliar o resultado auditivo dos pacientes adultos implantados com o implante coclear multicanal pelo Grupo de Implante Coclear da Disciplina de Otorrinolaringologia da Faculdade de medicina da Universidade de São Paulo. FORMA DE ESTUDO: Estudo de série. CASUÍSTICA E MÉTODO: Foram selecionados 61 pacientes com surdez profunda bilateral que utilizam o implante coclear multicanal por pelo menos seis meses e estudados os resultados auditivos através de testes de reconhecimento de palavras e sentenças. RESULTADOS: O PTA médio obtido pelos pacientes foi 38.7 dB NPS. A média em reconhecimento de sentenças em formato aberto foi de 71.3%, vogais em 86.5%, monossílabos em 52.60% e consoante medial em 52.6%. A maioria dos pacientes está apta ao uso do telefone. CONCLUSÃO: A avaliação auditiva obtida seis meses após a primeira programação do implante demonstra que pacientes de língua portuguesa obtêm excelentes resultados em testes de reconhecimento de palavras e sentenças em apresentação aberta, readquirindo uma audição útil.Complete hearing loss is a very important handicap resulting in sensory deprivation and affecting an individual's personality, relationships and life style. Individuals with profound deafness are unable to hear environmental sounds as doorbells, telephones, traffic noises and sirens that are

  10. LE «SOTTIGLIEZZE DI CERTA DIDATTICA SUPERLATIVA» DELLA GRAMMATICA ELEMENTARE: STORIA (ATTESTATA DEL METODO RAFFORZISTA (1814-1914

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    Michela Dota

    2018-03-01

    Full Text Available Il contributo ripercorre la storia e le peculiarità del metodo rafforzista, metodo glottodidattico per l’insegnamento della lettura e della scrittura. Il metodo, nato in Italia nel primo Ottocento, nell’epoca postunitaria era praticato nelle scuole elementari soprattutto dell’Italia meridionale, nonché nelle scuole reggimentali e in alcuni istituti per sordomuti. Le sue fondamenta, aberranti rispetto alla norma ortografica e ortoepica tradizionale, lo resero obiettivo di un tenace ostracismo da parte del Ministero dell’Istruzione pubblica, sostenuto per questa occasione da due tra i più eminenti glottologi dell’epoca: Graziadio Isaia Ascoli e Francesco Lorenzo Pullè. Il metodo finì per estinguersi nel secondo decennio del Novecento.   The history of the “metodo rafforzista” for teaching Italian (1814-1914 This article retraces the history and peculiarities of the “metodo rafforzista”, a language teaching method developed in Italy during the first part of 1800s. In the post-Unitarian period, it was used in elementary schools, especially in Southern Italy, and also in military schools and in some institutes for the Deaf and Dumb. Orthographic and orthoepic models proposed by the “metodo rafforzista” diverged from rules of traditional Italian grammar. The method, supported by Graziadio Isaia Ascoli and Francesco Lorenzo Pullè, two of the most distinguished Italian linguists at that time, was subsequently rejected by the Ministry of Public Education, and it vanished during the second half of 1900s.

  11. DOLOČITEV POVRŠINSKE NAPETOSTI Z METODO KAPILARNEGA DVIGA DVOFAZNIH SISTEMOV

    OpenAIRE

    Kravanja, Gregor

    2014-01-01

    Namen magistrske naloge je bil postavitev merilne naprave in razvoj nove metode merjenja površinske napetosti s kapilarnim dvigom dvofaznih sistemov v okolici kritične točke. Za pridobitev natančnih in primerljivih meritev je bilo potrebno poznati natančni notranji premer tankih kapilar. Določili smo ga z metodo laserskega tipanja na nemški koordinatni merilni napravi ZEISS tipa UMC-850 s pomočjo merilne programske opreme CALYPSO 5.1.4. Za merjenje ravnotežne višine smo uporabili računalniški...

  12. Correlacion entre metodos de analisis de Zn disponible en cuatro ordenes de suelos de Costa Rica

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    Eloy Molina

    2001-01-01

    Full Text Available Se realizo una comparación entre métodos analisis del Zn disponible en 4 ordenes de sue- Analytilos de Costa Rica (Ultisoles, Vertisoles, Andisoles Inceptisoles, 25 de c/u, utilizando las siguientes soluciones extractoras: Olsen Modificado, Meh- lich 3, Morgan Modificado, DTPA y HC1. Las cantidades de Zn extrafdas dependieron de la natu- raleza qufmica de la solucion extractora. El HCl presento los contenidos mas altos de Zn en los chasuelos, excepto en Vertisoles. Las soluciones que hicontienen el agente quelante EDTA (Olsen Modi- ficado y Mehlich`3, extrajeron niveles interme- Modidios de Zn, en tanto que los metodos que contie- Den el quelato DTPA (Morgan Modificado y DT - PA, obtuvieron los valores mas bajos. Las corre- laciones de Zn extrafble entre los 5 metodos fue- signifirOD significativas en la mayona de los casos, tanto nivel de orden de suelos como en el conjunto de indivilos 100 suelos analizados. Los coeficientes de co- rrelacion mas altos, se presentaron entre Mehlich Morgan Modificado y DTPA. Las correlaciones Modifueron consistentes en los 4 ordenes, 10 que indica que estas soluciones poseen un amplio margen de adaptacion a diferentes tipos de suelo, siendo una caractenstica ventajosa para la selección de un metodo de analisis. El Olsen Modificado fue mas slighteficiente para la extraccion de Zn en suelos de pH ligeramente acido 0 neutro (Vertisoles e Inceptiso- les, que en suelos acidos (Ultisoles y Andisoles. EI HCI extrajo cantidades muy aItas de Zn que Moraparentementestan relacionadas con formas no disponibles para lag plantas. Se concluye que lag soluciones Mehlich 3, Morgan Modificado y DT - PA son semejantes en la forma de extraer Zn dispo- Dible, y podrian seT una altemativa para sustituir el metoda tradicional de Olsen Modificado utilizado en Costa Rica. Sin embargo,la eficiencia de ellas no puede seT establecida sino a traves de log estudios de correlacion contra rendimiento en invernadero y campo.

  13. Osservazioni sul principio di legalità come idea e come metodo nell’esperienza giuridica della Chiesa

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    Beatrice Serra

    2012-10-01

    SOMMARIO: 1. Introduzione - 2. – La struttura essenziale del concetto di legalità e la sua realizzazione radicale nel diritto della Chiesa. - 3. L’idea di legalità come “regola che sta prima” nel ius commune e la sua coesistenza con un approccio empirico, essenzialmente giurisprudenziale e dottrinale, di costruzione del diritto. Il principio di legalità come metodo di produzione del diritto nel pensiero giuridico moderno- 4. Il legame storico-concettuale fra il principio di legalità e i Codici moderni - 5. Il Codex iuris canonici del 1917 e il principio di legalità come metodo di costruzione del ius ecclesiae in funzione della certezza del diritto - 6. (segueUlteriori riflessi della prima codificazione canonica sul principio di legalità.:

  14. Estudio numerico y experimental del proceso de soldeo MIG sobre la aleacion 6063--T5 utilizando el metodo de Taguchi

    Science.gov (United States)

    Meseguer Valdenebro, Jose Luis

    improvement on mechanical properties in aluminum metal joint. Los procesos de soldadura por arco electrico representan unas de las tecnicas mas utilizadas en los procesos de fabricacion de componentes mecanicos en la industria moderna. Los procesos de soldeo por arco se han adaptado a las necesidades actuales, haciendose un modo de fabricacion flexible y versatil. Los resultados obtenidos numericamente en el proceso de soldadura son validados experimentalmente. Los principales metodos numericos mas empleados en la actualidad son tres, metodo por diferencias finitas, metodos por elementos finitos y metodo por volumenes finitos. El metodo numerico mas empleado para el modelado de uniones soldadas, es el metodo por elementos finitos, debido a que presenta una buena adaptacion a las condiciones geometricas y de contorno ademas de que existe una diversidad de programas comerciales que utilizan el metodo por elementos finitos como base de calculo. Este trabajo de investigacion presenta un estudio experimental de una union soldada mediante el proceso MIG de la aleacion de aluminio 6063-T5. El metodo numerico se valida experimentalmente aplicando el metodo de los elementos finitos con el programa de calculo ANSYS. Los resultados experimentales obtenidos son: las curvas de enfriamiento, el tiempo critico de enfriamiento t4/3, geometria del cordon, microdurezas obtenidas en la union soldada, zona afectada termicamente y metal base, dilucion del proceso, areas criticas intersecadas entre las curvas de enfriamiento y la curva TTP. Los resultados numericos son: las curvas del ciclo termico, que representan tanto el calentamiento hasta alcanzar la temperatura maxima y un posterior enfriamiento. Se calculan el tiempo critico de enfriamiento t4/3, el rendimiento termico y se representa la geometria del cordon obtenida experimentalmente. La zona afectada termicamente se obtiene diferenciando las zonas que se encuentran a diferentes temperaturas, las areas criticas intersecadas entre las

  15. Electronic methods for discriminating scintillation shapes; Methodes electroniques de discrimination des formes des impulsions issues de scintillateurs; Ehlektronnye metody diskriminatsii form stsintillyatsii; Metodos electronicos de discriminacion de forma de impulsos de centelleo

    Energy Technology Data Exchange (ETDEWEB)

    Forte, M; Konsta, A; Maranzana, C [European Atomic Energy Community, CCR, ISPRA (Italy)

    1962-04-15

    ne doit se faire qu'entre deux types d'impulsions seulement (neutrons et rayons gamma, par exemple), on a egalement envisage l'emploi de reseaux passifs qu'il serait possible d'ameliorer et de simplifier. Les auteurs ont fait l'essai de quelques reseaux; ils sont notamment parvenus, en presence d'un bruit de fond du a des rayons gamma, a realiser la discrimination dans des scintillateurs liquides de protons de recul ne delivrant que de faibles impulsions (quelques dizaines de photo-electrons) et celle de fragments de capture de neutrons dans des scintillateurs liquides contenant du bore. Certains de ces reseaux ont pu fonctionner avec des impulsions de meme polarite issues de deux des dernieres dynodes, et meme avec les impulsions de sortie delivrees par une seule electrode. Il y a la une possibilite interessante pour les cas ou il est indique d'utiliser l'anode separement, par exemple pour le cycle de synchronisation. (author) [Spanish] Como ya se ha senalado, la forma de los impulsos emitidos por un centelleador, que es caracteristica del tipo de particula excitante (electron, proton, particulas alfa, etc.), puede convertirse en una amplitud de impulso como parametro independiente. Ello permite determinar, utilizando un analizador multicanal, la composicion de un haz mixto de particulas que excite el centelleador. Este metodo se ha aplicado con exito empleando varios centelleadores de tipo organico e inorganico. Los autores describen con detalle las tecnicas electronicas utilizadas para convertir la forme de los impulsos. En el caso mas sencillo de discriminacion entre solo dos clases de impulsos (por ejemplo, discriminacion de neutrones y rayos gamma), se ha estudiado la conveniencia de utilizar redes pasivas, susceptibles de nuevos perfeccionamientos y simplificaciones. Se han ensayado varios tipos de redes y el principal resultado obtenido consiste en la discriminacion, en presencia de un fondo gamma, de los protones de retrocesco en centelleadores liquidos

  16. Atlas de aves: Un metodo para documentar distribucion y seguir poblaciones

    Science.gov (United States)

    Robbins, C.S.; Dowell, B.A.; Dawson, D.K.; Alvarez-Lopez, Humberto; Kattan, Gustavo; Murcia, Carolina

    1988-01-01

    Los Atlas de Aves son proyectos nacionales o regionalies para trazar en mapas la distribucion en reproduccion de cada especie de ave. Ese procedimiento se esta usando en Europa, Australia, Nueva Zelanda, Norteamerica, y partes de Africa. El tama?o de los cuadrados varia de medio grado de latitud y Iongitud hasta 5 x 5 km. El trabajo de campo de cada proyecto exige aproxlmadamente cinco a?os, pero los aficionados pueden llevar a cabo la mayor parte del trabajo. Es posible almacenar los resultados en un computador personal. Hay muchos beneficios: (I) se presenta la distribucion corriente de las aves de la nacion, del estado, o de la Iocalidad; (2) se desarrolla nueva informacion especialmente sobre especies raras o en peligro; (3) se descubren areas que tienen una avlfauna sobresaliente o habitats raros y ayuda a su proteccion, (4) se documentan cambios de dlstribucion; (5) se pueden usar para documentar cambios de poblacion, especialmente en los tropicos donde otros metodos son mas dificiles de usar porque hay muchas especies y no hay muchos observadores calificados en la identificacion de sonidos de las aves; (6) son proyectos buenos de investigacion para estudiantes graduados; (7) los turistas y los jefes de excursiones de historia natural pueden contribuir con muchas informaciones

  17. Subsurface microbial ecology. Epi fluorescence direct counts; Ecologia microbica del sottosuolo: metodo di conta diretta in epifluorescenza

    Energy Technology Data Exchange (ETDEWEB)

    Barra Caracciolo, A.; Silvestri, C.; Creo, C.; Izzo, G. [ENEA, Centro Ricerche Casaccia, Rome (Italy). Dipt. Ambiente

    1998-07-01

    To the aim of recognize the importance of microorganisms in affecting or even determining the fate of xenobiotics in the subsurface environment evaluating bacteria concentration in a subsurface ecosystem, the report discusses a soil sample treatment method which has been developed for epi fluorescence direct counting with DAPI. [Italian] Lo studio discute un metodo di trattamento del campione per la conta diretta in epifluorescenza con un marcatore selettivo per il DNA, il DAPI, al fine di quantificare la concentrazione batterica del sottosuolo e studiare il ruolo dei microrganismi nella biodegradazione delle molecole esogene, ancora poco indagato.

  18. Data Evaluation Problems in the Pulsed Neutron Source Method; Problemes d'Evaluation des Donnees dans les Applications de la Methode de la Source Pulsee; Problemy otsenki dannykh pri primenenii metoda istochnika impul'snykh nejtronov; Problemas de Evaluacion de Datos en el Metodo de la Fuente de Neutrones Pulsados

    Energy Technology Data Exchange (ETDEWEB)

    Pal, L.; Bod, L.; Szatmary, Z. [Central Research Institute for Physics, Hungarian Academy of Sciences, Budapest (Hungary)

    1965-08-15

    moyen de transport dans de nombreuses matieres hydrogenees. (author) [Spanish] Desde hace mas de diez anos se viene empleando el metodo de los neutrones pulsados para determinar los parametros de difusion de los neutrones termicos. Este metodo ha resultado especialmente idoneo para el estudio de los moderadores hidrogenados. Los autores dan los resultados de las mediciones hechas en agua, benceno, tolueno, xileno, ciclohexano, n-hexano y difenilo, y examinan los metodos para evaluar con el minimo error los parametros de difusion de interes partiendo de los datos obtenidos en las mediciones. Se examina detenidamente, tanto en el plano teorico como en el experimental, el efecto de tiempo de vuelo que se manifiesta por razones tecnicas cuando se investigan moderadores a elevadas temperaturas, y que influye en el valor de la constante de desintegracion, y se exponen las condiciones geometricas en que se ha de operar para obtener resultados satisfactorios. Los autores determinan tambien el efecto que sobre la constante de desintegracion ejerce el tiempo muerto del detector neutronico y del amplificador, y demuestran que es despreciable cuando [i(t) {tau}]{sup 2} << 1, siendo i/t/dt el numero de neutrones detectados en el intervalo de tiempo/t, t + dt/, y {tau} el tiempo muerto. Se evaluo la constante de desintegracion empleando el metodo de la maxima probabilidad. Para determinar inequivocamente la funcion de probabilidad, se eligio un analizador multicanal que acumulaba como maximo una sola senal por ciclo de analisis y por canal. Se comprobo que la incorporacion del parametro caracteristico del fondo a la funcion de probabilidad tiene primordial importancia. Los parametros de la funcion de maxima probabilidad se evaluaron en una calculadora aplicando el metodo de iteracion de Newton. Cuando no se tiene debidamente en cuenta el fondo, este puede causar una mayor contaminacion aparente de armonicos, la cual, a su vez, puede interpretarse como un fondo aparente. Por ello es

  19. Multi-channel recording of a pulse spectrum on the screen of a Williams tube used with a ferrite memory analyser; Enregistrement du spectre d'impulsion sur l'ecran d'un tube de Williams au moyen d'un analyseur multicanal a memoire en ferrite; Zapis' spektra impul'sov na ehkrane ehlektronno-luchevoj trubki mnogokanal'nogo analizatora s ferritovoj pamyat'yu; Registro multicanal del espectro de los impulsos en la pantalla del tubo electronico, en un analizador con memoria de ferrita

    Energy Technology Data Exchange (ETDEWEB)

    Rumler, Shtirad [Institut Yadernogo Issledovannya Chekhoslovatskoj Akldemii Nauk, Rzhezh Chekhoslovatskaya Sotsialisticheskaya Respublika (Czech Republic)

    1962-04-15

    The paper describes a block-diagram of programme circuits with which it is possible to obtain a multi-channel trace of an expanded pulse-spectrum analysis on the screen of a Williams tube used in combination with a static ferrite memory. The conventional methods of direct recording on a Williams tube are in some cases unsatisfactory with the type of analyser in question, the trace being insufficiently clear, especially for the analysis of intermittent pulse cascades with a low-repetition frequency and a small average number of pulses. This is because the information to be read is interpreted in the channel straight from the adding circuits and address circuits with direct recording on the screen. The direct recording is unsuitable owing to the small average number of pulses and the statistically intermittent distribution. In this regard, the method proposed is better. The quality of the recording depends neither on the shape of the spectrum nor on the pulse-counting rate. This method is used in a 256-channel analyser with a ferrite memory of dead-time 15 {mu}s. An oscillographic trace, with a period equal to that of the spectrum analysis cycle, is produced periodically at a frequency of 50 cycles per second. The period of the trace cycle is approximately 4 ms, i.e. 20% of the total duration of the working-cycle of the analyser. In the case of analysers with a smaller number of channels and with a memory of shorter dead-time, the time for the oscillographic recording is only a few percent of the duration of the working-cycle of the analyser. (author) [French] L'auteur decrit un bloc-diagrammes des circuits de programmation qui, associes a une memoire statique en ferrite, permettent l'enregistrement multicanal, sur l'ecran d'un tube a rayons cathodiques, du spectre forme par les impulsions a analyser. Il est apparu que dans certains cas, les procedes habituels d'enregistrement, direct sur un tube de ce genre sont imparfaits lorsqu'on utilise un selecteur du modele

  20. Method to allow the estimation of heat transfer coefficients in solar stills; Metodo para determinar coeficientes locales de transferencia de calor en destiladores solares

    Energy Technology Data Exchange (ETDEWEB)

    Rubio Cerda, Eduardo; Porta Gandara, Miguel A [CIBNOR, Mexico D.F (Mexico); Fernandez Zayas, Jose Luis [UNAM Mexico, D.F. (Mexico)

    2000-07-01

    This work reports an experimental method that allows to estimate the heat transfer coefficients in the neighborhood of walls or flat plates subject to convective transport phenomena. This method can be applied to a great variety of thermal systems since it is based on the knowledge of the border condition for the temperature at the surface of the plate, and the temperature profile that characterize the dimensionless coefficient of heat transfer in the fluid, according to its definition given by the Nusselt number. The approach of this work are the foundations of the method and the system that has been developed to apply it, that incorporates automatic acquisition equipment for continuos monitoring of the information and elements to control the parameters of interest. In addition, the experimental cavities on which the method will be evaluated are discussed, considering two different scales, as well as experiments in cavities filled with air, and with a mixture of air and steam water, as is the case for solar distillation. [Spanish] En este trabajo se presenta un metodo que permite determinar de manera experimental coeficientes de transferencia de calor por conveccion. Este metodo puede ser aplicado a una gran variedad de sistemas termicos ya que se fundamenta en el conocimiento de la condicion de frontera para la temperatura en la superficie de la placa, y del perfil de temperaturas que caracteriza el coeficiente adimensional de transferencia de calor en el fluido, de acuerdo a la definicion de este, dada por el numero de Nusselt. El trabajo que aqui se reporta esta enfocado a la fundamentacion del metodo y al equipamiento que se ha desarrollado para instrumentarlo, que incorpora equipos automaticos de adquisicion continua de informacion y elementos de control para los parametros de interes. Se presentan ademas, las cavidades experimentales sobre las que sera evaluado el metodo, que considera dos escalas diferentes, asi como experimentos en cavidades llenas de aire

  1. Microscale adaptation of the potentiometric method with ion-selective electrode for the quantification of fluoride; Adaptacion a microescala del metodo potenciometrico con electrodo ion selectivo para la cuantificacion de fluoruro

    Energy Technology Data Exchange (ETDEWEB)

    Guevara Ruiz, Paulina; Ortiz Perez, Maria Deogracias [Laboratorio de Bioquimica, Facultad de de Medicina, Universidad Autonoma de San Luis Potosi, San Luis Potosi, San Luis Potosi, (Mexico)]. E-mail: mdortiz@uaslp.mx

    2009-05-15

    Similarly to other countries, ground water from Mexico is naturally polluted by fluoride. The main effects of fluoride at typical ground water concentrations are dental fluorosis, neurological deficits and reproductive disorders. In order to verify that the fluoride concentration is within the allowed guideline in Mexico (NOM 127 and 201), it is important to monitor fluoride levels in water and commercial beverages. The aim of this work is to develop a modification of the standard potentiometric method for fluoride determination in water, in order to reduce costs and amount of potentially toxic waste substances. Both methods were validated, the standard potentiometric method with the ion selective electrode and the microscale modification proposed in this paper. The methods were compared using statistic tests and graphics, followed by the comparison of 125 samples of commercial bottled water sold in the city of San Luis Potosi. Optimal results were obtained for the validation of both methods, and the microscale modification showed statistically identical results to those obtained with the standard method in all samples of bottled water. The microscale modification is a good alternative for fluoride assessment in water and beverages, and it represents a 95 % reduction of costs and chemical waste. [Spanish] En varios paises, incluido Mexico se presenta una contaminacion natural con fluoruro en agua subterranea; los principales efectos en la salud observados en poblacion expuesta a concentraciones mayores al valor permisible (que en Mexico es de 1.5 mg/L) son la fluorosis dental y esqueletica, asi como dano reproductivo y neurologico. En varios estados de la republica Mexicana, este problema es aun desconocido, de ahi la necesidad de evaluar las concentraciones de fluoruro en agua de consumo en varias comunidades. Asi, el objetivo de este trabajo es desarrollar un metodo a microescala para la determinacion de fluoruro en agua, que al reducir la cantidad de reactivo y

  2. Torque calculation in the induction motor with the finite element method; Calculo del par en el motor de induccion con el metodo del elemento finito

    Energy Technology Data Exchange (ETDEWEB)

    Castillo Diaz, Ramon

    2002-06-15

    In this work the method of the finite element is applied to the bi-dimensional analysis of the induction motor in operation in steady state, excited by sine sources of laminar currents and sine sources of voltage. The analysis is focused mainly in the calculation of the electromagnetic torque. The topics of electromagnetic theory are covered and in an idealized model of the induction motor, analytically and numerically with the method of the finite element, in the variant method of Galerkin, the vectorial potential and the torque are calculated. The results obtained with the analytical and numerical methods are compared. Three formulations are developed to calculate the torque with the method of the finite element, using triangular elements of first order, based in the equation of force of Lorentz, the Maxwell tensor and the principle of the virtual work. Finally, a motor of induction of real characteristics is simulated, assuming it is connected to a three-phase voltage source. In this motor it is analyzed the convergence and the evolution in the results obtained of the torque with different discretions, and the torque-velocity performance curve is calculated. [Spanish] En este trabajo se aplica el metodo del elemento finito al analisis bidimensional del motor de induccion en operacion en estado estable, excitado por fuentes de corriente laminar senoidales y fuentes de voltaje senoidales. El analisis se enfoca principalmente en el calculo del par electromagnetico. Se tratan los topicos de teoria electromagnetica involucrados y en un modelo idealizado del motor de induccion, se calculan analitica y numericamente con el metodo del elemento finito, en la variante metodo de Galerkin, el potencial vectorial y el par. Se comparan resultados obtenidos con los metodos analiticos y numericos. Se desarrollan tres formulaciones para calcular el par con el metodo del elemento finito, utilizando elementos triangulares de primer orden, basadas en la ecuacion de fuerza de

  3. Flow measurement in a 170-MW hydraulic turbine using the Gibson method; Medicion del flujo de una turbina hidraulica de 170 MW utilizando el metodo Gibson

    Energy Technology Data Exchange (ETDEWEB)

    Urquiza, Gustavo [Universidad Autonoma del Estado de Morelos (Mexico); Adamkowski, Adam [The Szewalski Institute of Fluid-Flow Machinery (Poland); Kubiak, Janusz; Sierra, Fernando [Universidad Autonoma del Estado de Morelos (Mexico); Janicki, Waldemar [The Szewalski Institute of Fluid-Flow Machinery (Poland); Fernandez, J. Manuel [Comision Federal de Electricidad (Mexico)

    2007-07-15

    This paper describes the methodology applied for measuring water flow through a 170-MW hydraulic turbine. The flow rate was measured using the pressure-time method, also known as the Gibson method. This method uses the well-known water hammer phenomenon in pipelines; in turbine penstocks, for instance. The version of this method used here is based on measuring, during total stop of the water stream, the time-history of pressure change in one section of the turbine penstock and relate it to the pressure in the upper reservoir to which the penstock is connected. The volumetric flow rate is determined from the relevant integration of the measured temporary pressure rise. Flow measurement was possible this way because the influence of the penstock inlet was negligible as far as an error of the measurement is concerned. The length of the penstock was 300 m. Previous experience and a standard IEC-41-1991 were the criteria adopted and applied. A fast and efficient acquisition system, including a 16 bit card, was used. The flow rate was calculated using a computer program developed and tested on several cases. The results obtained with the Gibson method were used for calibration of the on-line flow measuring system based on the Winter-Kennedy method as one of the index methods. This method is very often used for continuous monitoring of the flow rate through hydraulic turbines, when the calibration has been done on site by using the results of measurements obtained by the absolute method. Having measured the flow rate and output power, the efficiency was calculated for any operating conditions. A curve showing the best operating conditions based on the highest efficiency is presented and discussed. The details of the instrumentation, its installation, and the results obtained are discussed in the paper. [Spanish] Este articulo describe la metodologia aplicada para la medicion del flujo en una turbina hidraulica de 170 MW. El flujo se midio utilizando el metodo de presion

  4. Flow in potential cascades by means of the finite element method; Flujo en cascadas potenciales mediante el metodo del elemento finito

    Energy Technology Data Exchange (ETDEWEB)

    Sosa Cordero, Rodolfo; Fernandez Valencia, Gonzalo [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1987-12-31

    This article presents a mathematical model and its solution by means of the finite element method with approximate Garlekin formulation, for the flow analysis in a circular cascade, in a surface of revolution current of a turbo- machine, that can be axial, mixed or radial. To the revolution surface an agreed transformation is applied to obtain a plane, eliminating in this form one term in the equation succeeding in avoiding an iterative solution. Likewise, the finite element method allows to solve the equation in partial derivatives of the elliptical type in its quasi-harmonic form. Additionally, the method followed to introduce the contour conditions is presented; specially, the Kutta-Joukowsky conditions and the one of periodicity, which distinguishes this problem from the classical problems of ideal flows evaluated in the contour. [Espanol] En este articulo se presenta un modelo matematico y su solucion mediante el empleo del metodo del elemento finito con formulacion aproximada de Galerkin, para el analisis del flujo en una cascada circular, en una superficie de corriente de revolucion de una turbomaquina, que puede ser axial, mixta o radial. A la superficie de revolucion se le aplica una transformacion conforme para obtener un plano, eliminando de esta forma un termino en la ecuacion logrando evitar la solucion iterativa. Asimismo, el metodo del elemento finito permite resolver la ecuacion en derivadas parciales del tipo eliptico en su forma cuasiarmonica. Se presenta, ademas, el metodo seguido para introducir las condiciones de contorno; en especial, las condiciones de Kutta-Joukowsky y la de periodicidad, que distinguen a este problema de los problemas clasicos de flujos ideales valuados en el contorno.

  5. Flow in potential cascades by means of the finite element method; Flujo en cascadas potenciales mediante el metodo del elemento finito

    Energy Technology Data Exchange (ETDEWEB)

    Sosa Cordero, Rodolfo; Fernandez Valencia, Gonzalo [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1986-12-31

    This article presents a mathematical model and its solution by means of the finite element method with approximate Garlekin formulation, for the flow analysis in a circular cascade, in a surface of revolution current of a turbo- machine, that can be axial, mixed or radial. To the revolution surface an agreed transformation is applied to obtain a plane, eliminating in this form one term in the equation succeeding in avoiding an iterative solution. Likewise, the finite element method allows to solve the equation in partial derivatives of the elliptical type in its quasi-harmonic form. Additionally, the method followed to introduce the contour conditions is presented; specially, the Kutta-Joukowsky conditions and the one of periodicity, which distinguishes this problem from the classical problems of ideal flows evaluated in the contour. [Espanol] En este articulo se presenta un modelo matematico y su solucion mediante el empleo del metodo del elemento finito con formulacion aproximada de Galerkin, para el analisis del flujo en una cascada circular, en una superficie de corriente de revolucion de una turbomaquina, que puede ser axial, mixta o radial. A la superficie de revolucion se le aplica una transformacion conforme para obtener un plano, eliminando de esta forma un termino en la ecuacion logrando evitar la solucion iterativa. Asimismo, el metodo del elemento finito permite resolver la ecuacion en derivadas parciales del tipo eliptico en su forma cuasiarmonica. Se presenta, ademas, el metodo seguido para introducir las condiciones de contorno; en especial, las condiciones de Kutta-Joukowsky y la de periodicidad, que distinguen a este problema de los problemas clasicos de flujos ideales valuados en el contorno.

  6. Method of identifying the friction of rotors using the wavelet transform; Metodo para identificar el rozamiento de rotores utilizado la transformada wavelet

    Energy Technology Data Exchange (ETDEWEB)

    Jauregui Correa, Juan Carlos; Rubio Cerda, Eduardo; Gonzalez Brambila, Oscar [CIATEQ, A.C., Queretaro (Mexico)

    2007-11-15

    The modern processes of signal analysis that measure mechanical vibrations are based on the fast transform of Fourier (FFT), nevertheless, this method is not able to identify transient phenomena nor of nonlinear nature. Although many efforts have been made to try to identify these phenomena in the frequency spectra, it is not possible to correlate the spectra with the physical characteristics of this type of phenomena. Within these phenomena on the rubbing of a rotor against the housing or trunnion of a bearing, this phenomenon has a nonlinear behavior, as it is demonstrated in this paper. In the first part a method based on the of signal analysis type wavelets is presented and how this technique can be used to predict transient and nonlinear phenomena. Once defined the method, its application in the identification of the friction of rotors is demonstrated. With this, one demonstrates that the method presented in this paper allows to also identifying in real time the rubbing phenomenon and also that it can be used as an of analysis technique in the preventive maintenance systems. [Spanish] Los procesos modernos de analisis de senales que miden vibraciones mecanicas se basan en la transformada rapida de Fourier (FFT por sus siglas en ingles), sin embargo, este metodo no es capaz de identificar fenomenos transitorios ni de naturaleza no lineal. A pesar de que se han hecho muchos esfuerzos para tratar de identificar estos fenomenos en los espectros de frecuencia, no es posible correlacionar el espectro con las caracteristicas fisicas de este tipo de fenomenos. Dentro de estos fenomenos sobre el rozamiento de un rotor contra la carcasa o munon de una chumacera, este fenomeno tiene un comportamiento no lineal, como se demuestra en este trabajo. En la primera parte se presenta un metodo basado en el analisis de senales tipo wavelets y como esta tecnica puede utilizarse para predecir fenomenos transitorios y no lineales. Una vez definido el metodo, se demuestra su

  7. Multichannel analyzer embedded in FPGA; Analizador multicanal embebido en FPGA

    Energy Technology Data Exchange (ETDEWEB)

    Garcia D, A.; Hernandez D, V. M.; Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98060 Zacatecas, Zac. (Mexico); Ordaz G, O. O. [Universidad de Cordoba, Departamento de Arquitectura de Computadores, Electronica y Tecnologia Electronica, Campus de Rabanales, Ctra. N-IVa Km 396, 14071 Cordoba (Spain); Bravo M, I., E-mail: angelogarciad@hotmail.com [Universidad de Alcala de Henares, Departamento de Electronica, Campus Universitario, Carretera Madrid-Barcelona Km 33.600, 28801 Alcala de Henares, Madrid (Spain)

    2017-10-15

    Ionizing radiation has different applications, so it is a very significant and useful tool, which in turn can be dangerous for living beings if they are exposed to uncontrolled doses. However, due to its characteristics, it cannot be perceived by any of the senses of the human being, so that in order to know the presence of it, radiation detectors and additional devices are required to quantify and classify it. A multichannel analyzer is responsible for separating the different pulse heights that are generated in the detectors, in a certain number of channels; according to the number of bits of the analog to digital converter. The objective of the work was to design and implement a multichannel analyzer and its associated virtual instrument, for nuclear spectrometry. The components of the multichannel analyzer were created in VHDL hardware description language and packaged in the Xilinx Vivado design suite, making use of resources such as the ARM processing core that the System on Chip Zynq contains and the virtual instrument was developed on the LabView programming graphics platform. The first phase was to design the hardware architecture to be embedded in the FPGA and for the internal control of the multichannel analyzer the application was generated for the ARM processor in C language. For the second phase, the virtual instrument was developed for the management, control and visualization of the results. The data obtained as a result of the development of the system were observed graphically in a histogram showing the spectrum measured. The design of the multichannel analyzer embedded in FPGA was tested with two different radiation detection systems (hyper-pure germanium and scintillation) which allowed determining that the spectra obtained are similar in comparison with the commercial multichannel analyzers. (Author)

  8. A reverse method to estimate initial temperatures in geothermal reservoirs; Un metodo inverso para estimacion de la temperatura inicial de yacimientos geotermicos

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Gutierrez, Alfonso [Instituto de Investigaciones Electricas, Gerencia de Geotermia, Cuernavaca, Morelos (Mexico)]. E-mail: aggarcia@iie.org.mx; Ramos Alcantara, Jose R. [Centro Nacional de Investigacion y Desarrollo Tecnologico, Departamento de Ingenieria Mecanica, Cuernavaca, Morelos (Mexico); Arellano Gomez, Victor M. [Instituto de Investigaciones Electricas, Gerencia de Geotermia, Cuernavaca, Morelos (Mexico)

    2010-01-15

    A method is presented for estimating the initial temperature in geothermal-reservoir formations. The method is based on control theory where the measured temperatures or temperature logs are compared with corresponding simulated temperatures for different times with the well closed. The comparison is made using a control algorithm that makes changes to the originally assumed reservoir temperatures and performs iterations until the best fit between the temperature logs and the simulated temperatures is obtained. The simulation of fluid transport and heat in the well includes the processes of circulation and stop in the presence of circulation losses, modeled on macroscopic balances of momentum and energy. The transport processes in the formation regard the reservoir as an isotropic porous medium and fluid flow is described by Darcy's law. This model generates the fields of temperatures, pressures and speeds as a function of time and space. The method was tested with data from well LV-3 in Las Tres Virgenes geothermal field, Baja California Sur, Mexico. The estimated temperatures of the undisturbed formation-or initial temperatures-are compared within {+-}15 degrees Celsius with the measured temperatures, which is an acceptable outcome from an engineering point of view. [Spanish] Se presenta un metodo para la estimacion de la temperatura inicial en las formaciones de yacimientos geotermicos. El metodo se basa en la teoria de control donde las temperaturas medidas o registros de temperatura se comparan con las correspondientes temperaturas simuladas a diferentes tiempos con el pozo cerrado. La comparacion se hace usando un algoritmo de control el cual hace cambios a las temperaturas de yacimiento originalmente supuestas y realiza iteraciones hasta que se obtiene el mejor ajuste entre los registros de temperatura y las temperaturas simuladas. La simulacion del transporte de fluidos y calor en el pozo incluye los procesos de circulacion y paro en presencia de

  9. L’utilizzo della ricostruzione nella comunicazione del patrimonio archeologico. L’approccio, il metodo, le finalità e alcuni spunti di discussione.

    Directory of Open Access Journals (Sweden)

    Elena Bacci

    2010-05-01

    In questo contributo si focalizza l’attenzione sulla ricostruzione grafica e virtuale del patrimonio e sulle sensazioni che la ricostruzione evoca nel fruitore del messaggio culturale. La ricostruzione si attua mediante la collaborazione tra archeologo e illustratore e costituisce un momento di verifica visiva dell’interpretazione archeologica e uno strumento di comunicazione del dato archeologico fruibile a più livelli. Ciò avviene grazie allo scambio costante di informazioni (dati scientifici e proposte di ricostruzione e il confronto che ne deriva determina i metodi e le fasi di avanzamento del progetto. Il metodo si basa sull’integrazione delle immagini 3D con il disegno tradizionale ed è finalizzato alla trasposizione del dato archeologico, in modo tale da garantire alla ricostruzione il duplice requisito di soddisfazione estetica e credibilità scientifica.

  10. A method for optimization of patient dose estimation in conventional radiology; Un metodo per l'ottimizzazione della stima della dose al paziente nella radiologia tradizionale

    Energy Technology Data Exchange (ETDEWEB)

    Tofani, A.; Del Corona, A. [Azienda Unita' Sanitaria Locale 6, Livorno (Italy). Unita' Ospedaliera di Fisica Sanitaria; Niespolo, A. [Azienda Ospedaliera Pisana, Pisa (Italy). Unita' Ospedaliera di Fisica Sanitaria

    2000-05-01

    found to depend on the average body surface, a parameter which takes into account both patient height and mass. Thus, determining the normalization factor for each projection and each view allows to estimate the absorbed dose under different geometrical conditions. The method has been verified by considering four of the most common X-ray procedures (chest AP, cervical spine LAT, lumbar spine AP and head LAT). The average error on dose estimation is about 13 %. In the very next future the method will be extended to all the projections and views of ICRP Report no. 34, and we plant to integrate the described algorithm in a computer program devoted to the automatic computation of patient dose. [Italian] Il metodo raccomandato dalla International Commission on Radiological Protection (ICRP) nel suo Report n. 34(1982) per il calcolo della dose al paziente negli esami di radiodiagnostica e' basato su dati dosimetrici tabulati ottenuti mediante simulazioni Monte Carlo su fantocci antropomorfi descritti da semplici funzioni matematiche. Nel caso del calcolo della dose per un paziente adulto, le limitazioni principali di questo metodo sono due: in primo luogo i parametri geometrici dell'esame - e in particolare la distanza fuoco-pellicola e il formato della pellicola- sono fissi, e questo rende problematico l'utilizzo dei dati dosimetrici nelle condizioni effettive in cui si e' svolto l'esame, che in genere non coincideranno con quelle standard ICRP. Inoltre quando le dimensioni e la massa del paziente differiscono sensibilmente da quelle del fantoccio utilizzato nelle simulazioni (il cosidetto uomo di riferimento, di altezza pari a 174 cm e massa di 70,9 Kg) il metodo ICRP puo' portare a errori considerevoli nella stima della dose. Lo scopo del presente lavoro e' quello di indicare una possibile via di uscita per superare queste limitazioni. L'algoritmo proposto in questo lavoro si basa sull'applicazione del metodo suggerito da Huda e

  11. Fundamentos del metodo cientifico

    Directory of Open Access Journals (Sweden)

    Badii, M. H.

    2004-01-01

    Full Text Available El objetivo de esta obra no radica en realizar una búsqueda exhaustiva de la literatura en el tema, sino, sentar las bases del método científico, notando los aspectos filosóficos e éticos de la ciencia. Se presentan los conceptos y definiciones fundamentales relacionados con la metodología de la investigación científica. Se maneja el concepto de la toma de los datos válidos como un requisito básico en cualquier trabajo científico. Se pone a disposición del lector un modelo denominado el ECOEE que es una herramienta poderosa para establecer puntos de comparación e discusión entre los resultados de diferentes trabajos científicos. Finalmente, ofrece unas sugerencias de que hacer o no hacer en cuanto a realizar un trabajo de investigación.

  12. Ultra-high-speed oscillographic techniques; Techniques d'oscillographie ultra-rapide; Metody sverkhskorostnoj ostsillografii; Metodos oscilograficos ultrarrapidos

    Energy Technology Data Exchange (ETDEWEB)

    Abercrombie, S; Elphick, B; Foster, H [Atomic Weapons Research Establishment, Aldermaston (United Kingdom)

    1962-04-15

    100 {Omega}; e) Des resistances de complement a large bande, destinees a l'extraction des signaux de declenchement de la base de temps; / ) Des bases de temps fournissant des signaux de l'ordre de quelques nanosecondes et comportant des dispositifs de declenchement et de suppression du faisceau; g) Un appareil de prise de vues a grande ouverture. En conclusion, le memoire examine certaines applications de l'electronique nucleaire. (author) [Spanish] Despues de un resumen historico de los metodos de utilizacion de oscilografos para senales transitorias de alta velocidad, los autores examinan sus limites de aplicacion practica. En la memoria se pasa revista a los tubos de rayos catodicos apropiados para estos oscilografos, tomando en cuenta especialmente los tipos de deflexion por onda progresiva. En la memoria se estudian los siguientes componentes de un oscilografo completo para senales transitorias: a) Un tubo de rayos catodicos con deflexion por onda progresiva con conexion coaxial balanceada y una anchura de banda de 2 GHz; b) Un transformador inversor de fase con una impedancia caracteristica de 100 y 50 {Omega} y una anchura de banda de 1,5 kHz a 1,5 GHz; c) Resistencias de terminacion coaxial para frecuencias del orden de los GHz; d) Condensadores de acoplamiento compensados para usarlos en lineas coaxiales con frecuencias comprendidas entre 5 kHz y 3 GHz y 100 {Omega} de impedancia caracteristica; e) Atenuadores resistivos de banda ancha, para la extraccion de senales de disparo de base de tiempos; f) Bases de tiempo del orden de los nanosegundos, con dispositivos disparadores y supresores ; g) Una camara de gran apertura. Finalmente, los autores examinan las aplicaciones de estos oscilografos en la electronica nuclear. (author) [Russian] Posle kratkogo opisaniya ostsillograficheskogo metoda izucheniya sverkhskorostnykh perekhodnykh izluchenij obsuzhdayutsya prakticheskie vozmozhnosti ehtogo apparata. Daetsya obzor podkhodyashchikh katodnykh ehlektronnykh lamp

  13. Development of an analytic method for arsenic's determination in lime and tortilla; Desarrollo de un metodo analitico para determinacion de arsenico en cal y tortilla

    Energy Technology Data Exchange (ETDEWEB)

    Huato Soberanis, Julio; Ogura, Tetsuya [Universidad Autonoma de Guadalajara, Guadalajara, Jalisco (Mexico)

    1995-02-01

    A spectrophotometric method to determine As in tortilla and lime has been optimized, modifying the AsH{sub 3} generator. The reaction between arsin (AsH{sub 3}){sub 4} and diethyldithiocarbamate of Ag (AgDDC); was followed spectrophotometrically. The conditions under which the As remains in the ash during the calcination of the tortillas were studied. It was found that when they were heated in a quartz tube with a careful control of the air flow and oxygen, as well as the heating temperature, the arsenic loss in minimized. [Spanish] Se ha optimizado el metodo para determinar As en la tortilla y cal mediante espectrometria en el visible del color producido en la reaccion entre Arsina (AsH{sub 3}){sub 4} y dietilditiocarbamato de plata (AgDDC); modificando el generador de AsH{sub 3}. Se han buscado las condiciones en las que el arsenico permanece en las cenizas de la calcinacion de las tortillas; encontrandose que las tortillas deben calentarse en un tubo de cuarzo con control del flujo de aire y oxigeno asi como de la temperatura de calentamiento.

  14. Application of the identification methods from Hilbert and Prony to the study of oscillatory phenomena in electrical power systems; Aplicacion de los metodos de identificacion de Hilbert y Prony al estudio de fenomenos oscilatorios en sistemas electricos de potencia

    Energy Technology Data Exchange (ETDEWEB)

    Andrade Soto, Manuel Antonio

    2002-10-15

    In the present thesis work the application of identification techniques is investigated based on methods of spectral analysis to the study of the instantaneous characteristics of signals obtained by means of digital simulation of the dynamic behavior of the power system. The study focuses on the perspectives developed from two different approaches of analysis: the use of lineal methods of spectral analysis and the use of methods of non-lineal analysis, based on the concept of an analytical signal. The developed tools are applied to the study of two phenomena of electromechanical origin of different characteristics in complex power systems. A comparison between the results obtained is performed for these techniques and the possibility of its application is discussed for the problem of on-line identification in power systems. [Spanish] En el presente trabajo de tesis se investiga la aplicacion de tecnicas de identificacion basadas en metodos de analisis espectral al estudio de las caracteristicas instantaneas de senales obtenidas mediante simulacion digital del comportamiento dinamico del sistema de potencia. El estudio se centra en las aproximaciones desarrolladas desde dos enfoques distintos de analisis: la utilizacion de metodos lineales de analisis espectral y la utilizacion de metodos de analisis no lineal, basados en el concepto de una senal analitica. Las herramientas desarrolladas se aplican al estudio de dos fenomenos de origen electromecanico de caracteristicas distintas en sistemas complejos de potencia. Se hace una comparacion entre los resultados obtenidos por estas tecnicas y se discute la posibilidad de su aplicacion al problema de identificacion en linea en sistemas de potencia.

  15. Validation of Hiriart equation to compute steam production by the lip pressure method; Validacion de la ecuacion de Hiriart para calculo de gasto de vapor por el metodo de presion de labio

    Energy Technology Data Exchange (ETDEWEB)

    Flores Armenta, Magaly [Gerencia de Proyectos Geotermoelectricos de la Comision Federal de Electricidad, Morelia (Mexico)

    1996-09-01

    Mainly in new geothermal wells, it is necessary to evaluate the production in a very fast, simple and not expensive way, to know the convenience to install surface equipment, such as silencers and separators, to drive the steam to the commercial gathering system. In practice, one of the most known methods is the lip pressure one, which requires a simple set of installations. The objective of this paper is to validate the steam flow rate calculated by the lip pressure method, with respect to the ASME method. The ASME method is known for its accuracy, and is done by measuring the steam and liquid after a high pressure separator, by an orifice plate of known diameter and a triangular weir. Results of the validation show up the feasibility of application of the lip pressure method by using a simple adjustment equation. Percentage of mistake results less than 1%, without any notable influence of the production enthalpy. That equation to be applied in a general case, is as follows: Q{nu} =(20642)(F*P*D{sup 2}/{radical}h-2000). For the particular case of the Los Azufres geothermal field, the equation is: Q{nu}= 810*P*D{sup 2} [Espanol] En los pozos geotermicos, principalmente en los nuevos, es necesario evaluar su produccion de manera rapida, sencilla y economica, para determinar la conveniencia de instalar equipo superficial, como separadores, silenciadores, etc., que permita la integracion del vapor al sistema comercial de generacion electrica. Para fines practicos uno de los metodos mas conocidos es el de presion de labio, que solo requiere un arreglo sencillo de instalaciones superficiales. En este documento se validan y ajustan los calculos de produccion de vapor por ese metodo de presion de labio, con respecto a las mediciones exactas efectuadas con el metodo ASME. Este ultimo es reconocido internacionalmente por su precision, y se lleva a cabo separando la mezcla obtenida en superficie en un recipiente a presion para medir el vapor a traves de una placa de orificio

  16. The Comparative Accuracy of the 4 {pi} Liquid Scintillation Counting Method of Radioisotope Standardization; L'exactitude comparee de la methode de comptage 4 {pi} a scintillateurs liquides pour l'etalonnage des radioisotopes; Sravnitel'naya tochnost' 4 {pi} zhidkogo stsintillatsionnogo metoda podscheta standartiziruemykh radioizotopov; Exactitud del metodo de recuento con centelleador liquido 4 {pi} para normalizar radioisotopos, comparada con la de otros metodos

    Energy Technology Data Exchange (ETDEWEB)

    Steyn, J [National Physical Research Laboratory, Pretoria (South Africa)

    1960-06-15

    The accuracy of the 4 {pi} liquid scintillation counting method of standardizing {beta} emitters was compared to 4 l{pi} {beta}-{gamma} coincidence counting for the nuclides Co{sup 60}, I{sup 131} and Au{sup 198}. For P{sup 32} the liquid counting results were compared to 4 {pi} proportional counting. The efficiency of the liquid scintillation counting method was found to be energy dependent, dropping to about 97.5% for Co{sup 60} which was the lowest energy {beta} emitter investigated. (author) [French] La precision de la methode de comptage 4 {pi} a scintillateurs liquides pour l'etalonnage des emetteurs {beta} a ete comparee au comptage par coincidences 4 {pi} {beta}-{gamma} pour le So{sup 60}, le I{sup 131} et le Au{sup 198}. Dans le cas du P{sup 32}, les resultats du comptage au liquide ont ete compares a ceux du comptage 4 {pi} proportionnel. On a constate que le rendement de la methode de comptage a scintillateurs liquides variait en fonction de l'energie emise et qu'il descendait a environ 97.5% pour le Co{sup 60} qui, de tous les emetteurs {beta} etudies, emet l'energie la plus faible. (author) [Spanish] El autor compara la precision del metodo de recuento con centelleador iquido 4 {pi} para normalizar emisores {beta} con la del metodo de coincidencias {beta}-{gamma} 4 {pi}, para los siguientes nuclidos: So{sup 60}, I{sup 131} y Au{sup 198}. En el caso del P{sup 32}, confronta los resultados del primer metodo con los obtenidos mediante el recuento proporcional 4 {pi}. Comprueba que la eficacia del metodo de recuento con centelleador liquido depende de la energia y desciende al 97.5%, aproximadamente, para el Co{sup 60}, que fue el emisor {beta} mas debil que se investigo. (author) [Russian] Tochnost' 4 {pi} zhidkogo stsintillyatsionnog o metoda podscheta standartiziruemogo {beta}-izluchatelya sravnivalas' s 4 {pi} {beta}-{gamma} metodom podscheta na sovpadeniyakh dlya izotopov So{sup 60}, I{sup 131} i Au{sup 198}. Dlya R{sup 32} rezultaty zhidkogo

  17. Some Non-Destructive Testing Methods Applicable to Sintered Materials; Quelques Methodes d'Essais Non Destructifs Applicables aux Materiaux Frittes; Nekotorye metody nedestruktivnykh ispytanii, primenimye k spechennym materialam; Algunos Metodos de Ensayo No Destructivo Aplicables a los Materiales Sinterizados

    Energy Technology Data Exchange (ETDEWEB)

    Labusca, Elena; Mirion, I.; Andreescu, N.; Alecu, M.; Biscoveanu, I. [Institut de Physique Atomique, Bucarest (Romania)

    1965-10-15

    solides frittes, a l'aide de la metallographie et de la microscopie electronique. Ces methodes mettent en evidence l'homogeneite de la structure, les dimensions et l'orientation des grains, la presence de defauts divers (inclusions, pores) et revolution meme du processus de frittage, y compris la formation des cristaux, la croissance granulaire, etc. Dans quelques cas, on peut combiner l'examen microscopique a des essais de microdurete. Cet examen de la structure microcristalline represente l'une des methodes principales de controle qualitatif des materiaux frittes, et ne peut etre remplace par aucun autre moyen d'investigation. 2. Controle du degre de consolidation, qui determine essentiellement la qualite des materiaux frittes. Ce controle est effectue par la mesure de quelques proprietes, telles que la conductibilite electrique et thermique, en correlation avec la densite, etant donne que la conductibilite des materiaux frittes est directement porportionnelle au degre de frittage. On a essaye aussi une methode adequate de controle de la porosite; on a obtenu des donnees experimentales interessantes, surtout au point de vue de la porosite libre, laquelle est susceptible aux inclusions gazeuses. Le memoire contient des donnees experimentales concernant l'application de ces methodes de controle a quelques materiaux frittes interessants pour la technologie nucleaire. (author) [Spanish] Teniendo en cuenta la estructura granular especifica de los materiales sinterizados, elaborados a partir de polvos, cuyo proceso de consolidacion se desarrolla en funcion del tratamiento de sinterizacion, los autores han estudiado algunos metodos para verificar el grado de sinterizacion y controlar ciertas propiedades. Entre los metodos no destructivos utilizados, se mencionan en la presente memoria: 1. Examen de la estructura cristalina de los solidos sinterizados por metalografia y microscopfa electronica. Estos metodos ponen de manifiesto el giado de homogeneidad estructural, la dimension

  18. Factors application of MW-mile method and participation in the allocation of charges by the drills use in electricity markets; Aplicacion de los factores de participacion y del metodo de MW-milla en la asignacion de cargos por uso de redes de transmision en mercados de electricidad

    Energy Technology Data Exchange (ETDEWEB)

    Alba-Gomez, L; Tovar-Hernandez, J. H; Gutierrez-Alcaraz, G [Instituto Tecnologico de Morelia, Michoacan (Mexico)]. E-mail: horaciotovar@mexico.com; ggutier@itmorelia.edu.mx

    2007-04-15

    Use of network allocation costs by shift factors and MW-Mile method is reported in this paper. Conventional shift factors are computed based on DC power flow. DC power flow requires to selecting a slack bus in order to avoid matrix singularity. Therefore, shift factors are slack bus dependent. In order to evade slack bus dependency, two approaches are considered. [Spanish] Este trabajo presenta la asignacion de costos por uso de red mediante la aplicacion de Factores de Participacion (FP) y el metodo de MW-Milla. Los FP clasicos son calculados a partir del modelo lineal de flujos de potencia para lo que se requiere de establecer un nodo de referencia a fin de eliminar la singularidad de la matriz de coeficientes. Por lo tanto, los FP son dependientes de la asignacion del nodo de referencia. Dos metodos alternativos para evitar la dependencia del nodo compensador en la obtencion de los factores de participacion son presentados.

  19. Development of a multichannel dosimeter for radiotherapy; Desenvolvimento de um dosimetro multicanal para radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Menezes, Claudio Jose Mesquita

    2000-06-01

    In radiotherapy, verification of the patient dose is of great important for the success of the treatment. Uncertainties in the evaluation of this dose can produce serious complications such as the loss of the control of the disease and damage to normal tissue. Semiconductor detectors present advantages over other types of radiation detectors such as ionization chambers and thermoluminescent dosimeters including small dimensions, high sensitivity and fast response. In this work, a multichannel dosimetric system is linear with dose, for a 6 MV x-ray beam and also with a beam of cobalt-60 gamma rays. The coefficients of determination of the calibration curves were better then 0,9998 in all cases. The four sensors presented similar response with the dose for different field sizes. The variation of the response was smaller than 1%. In a related study, depth dose was measured, and the results showed a good agreement compared to theoretical values. The angular response of the detectors showed a variation of 7% for angles of 45 deg C. Using the Anderson Random phantom, dose at the isocenter was determined from measurements of the surface dose. From the results obtained it can be concluded that the dosimetric system developed is adequate for the evaluation of many parameters in radiation fields used in radiotherapy. This system can be used to measure the patient entrance dose under treatment conditions, and the equipment can be used in the radiotherapy quality assurance program. (author)

  20. Development of a chromatographic method for the study of the stability and compatibility of Mexican fuel oils; Desarrollo de un metodo cromatografico para el estudio de estabilidad y compatibilidad de combustoleos mexicanos

    Energy Technology Data Exchange (ETDEWEB)

    Blass Amador, Georgina; Panama Tirado, Luz Angelica [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1992-11-01

    compatibility of fuel oil mixes. [Espanol] En Mexico, la mayoria de la energia electrica producida proviene del uso de combustibles residuales pesados conocidos como combustoleos los cuales han sufrido disminuciones en la calidad debido a una combinacion de factores, entre los que destaca el de los cambios en el proceso de refinacion. Es necesario desarrollar metodos que sean capaces de indicar la inestabilidad (formacion de sedimento o incremento en viscosidad durante el almacenamiento o calentamiento) o incompatibilidad (formacion de sedimento al mezclar dos o mas) de los combustoleos utilizados en las centrales termoelectricas. El objetivo de este trabajo fue el desarrollar una prueba alternativa para el estudio de la compatibilidad y/o estabilidad de combustoleos mexicanos empleando cromatografia de liquidos de alta resolucion (CLAR) y asi poder determinar aspectos estructurales del combustoleo que determinan su estabilidad. Dado que la formacion de sedimentos ocurre cuando el poder disolvente del combustible es inadecuado para mantener los asfaltenos en solucion, es importante conocer la medida del poder disolvente o aromaticidad del diluyente; asi pues, la primera parte de este trabajo se centro en la determinacion del perfil de compuestos aromaticos de los diluyentes de los combustoleos, la otra parte se dedico a la determinacion del perfil de distribucion de los pesos moleculares de los asfaltenos presentes en los combustoleos. Los perfiles de la fraccion aromatica, asi como los de distribucion de pesos moleculares se determinaron empleando cromatografia de liquidos, en la que se empleo una variedad de columnas y de disolventes. Se efectuo una combinacion de pruebas de rutina tales como contenido de asfaltenos, equivalencia de tolueno, viscosidad, etcetera con el fin de obtener correlaciones con el metodo cromatografico desarrollado. En este articulo se discute solo la seccion correspondiente a la obtencion del perfil de contenidos de aromaticos de los combustoleos. Se

  1. Sizing an isolated wind-solar-fuel cell generation system based on the particle swarm optimization method; Dimensionamiento de un sistema de generacion aislado eolico-solar-celda de combustible basado en el metodo de optimizacion de enjambre de particulas

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez-Huerta, V; Ramirez-Arredondo, Juan M. [Universidad de Quintana Roo, Chetumal, Quintana Roo (Mexico)]. E-mail: vsanchez@gdl.cinvestav.mx; Arriaga-Hurtado, L. G. [CIDETEQ, Queretaro (Mexico)

    2009-09-15

    Sizing an electric energy system requires an analysis of investment, maintenance and operating costs. In the case of a generation system that uses renewable sources, optimal capacity becomes more complex compared to a conventional system, because of the randomness of renewable resources (wind, solar) and the still high costs of wind and photovoltage generator modules. This work presents the optimal sizing of a wind-solar-fuel cell generation system, minimizing the costs of the system while satisfying the energy demands of an isolated charge. The optimization method used is based on an evolutionary programming technique known as particle swarms (PSO-particle swarm optimization). The generation of energy with a hybrid system is discussed, based on the profile of insolation and wind availability at the site, with the objective of satisfying a specific electric demand. [Spanish] El dimensionamiento de un sistema de generacion de energia electrica requiere un analisis de los costos de inversion, mantenimiento y operacion. En el caso de un sistema de generacion que utiliza fuentes renovables la capacidad optima resulta mas compleja con respecto a un sistema convencional, debido a la aleatoriedad de los recursos renovables (eolico, solar), y a los aun altos costos de generadores eolicos y modulos fotovoltaicos. En este trabajo se presenta el dimensionamiento optimo de un sistema de generacion eolico-solar-celda de combustible minimizando los costos del sistema que satisfaga la energia demandada por una carga aislada. El metodo de optimizacion utilizado esta basado en una tecnica de programacion evolutiva conocida como enjambre de particulas (PSO por sus siglas en ingles: particle swarm optimization). Se plantea la generacion de energia del sistema hibrido con base a la insolacion y el perfil del viento disponible en sitio, con objeto de satisfacer una demanda electrica determinada.

  2. A review of calculation methods for fast and intermediate reactors; Expose des methodes pour le calcul de reacteurs a neutrons rapides et intermediaires; Obzor metodov rascheta reaktorov na promezhutochnykh i bystrykh nejtronakh; Estudio panoramico de los metodos de calculo de los reactores rapidos e intermedios

    Energy Technology Data Exchange (ETDEWEB)

    Marchuk, G I [Akademiya Nauk, Moskva, Union of Soviet Socialist Republics (Russian Federation)

    1962-03-15

    This paper discusses the development of methods for calculating intermediate and fast reactors. It deals with various approaches to the problems of physical calculation. The calculation of resonance effects is discussed. Consideration is given to multi-group systems of fundamental and conjugate equations, various applications of perturbation theory to the problems of physical reactor calculation, and numerical methods of solving fundamental and conjugate reactor equations, which approximate the method of spherical harmonics. The paper describes an application of the response method to the solution of critical-mass problems, and methods of calculating reactors with hydrogeneous moderators. The fundamental features of an effective one-group reactor model are described. (author) [French] L'auteur examine la mise au point de methodes pour le calcul de reacteurs a neutrons rapides et intermediaires . Il decrit diverses manieres d'aborder les problemes des calculs sur la physique des reacteurs, notamment le calcul des effets de resonance. Il s'attache particulierement aux points suivants: systemes d'equations fondamentales et conjuguees a plusieurs groupes; diverses applications de la theorie des perturbations aux problemes de calculs sur la physique des reacteurs; methodes numeriques pour resoudre les equations fondamentales et conjuguees, voisines de la methode des harmoniques spheriques. L'auteur decrit ensuite une maniere d'appliquer la methode de la reponse aux problemes de la masse critique ainsi que des methodes pour le calcul de reacteurs ralentis a l'hydrogene. Il decrit les caracteristique s fondamentale s d'un modele de reacteur a un groupe effectif. (author) [Spanish] El autor analiza el desarrollo de los metodos de calculo de los reactores nucleares que trabajan con neutrones rapidos y con neutrones intermedios. Examina diversos planteos de los problemas del calculo fisico. Indica la forma de tomar en cuenta los efectos de resonancia y menciona los sistemas

  3. Rapid Methods of Determining Internal Radioactive Contamination; Methodes Rapides Permettant d'Evaluer la Contamination Radioactive Interne; 0411 042b 0414 ; Metodos Rapidos para Determinar la Contaminacion Radiactiva Interna

    Energy Technology Data Exchange (ETDEWEB)

    Sedlet, J.; Fairman, W. D.; Robinson, J. J. [Industrial Hygiene and Safety Division, Argonne National Laboratory, Argonne, IL (United States)

    1965-06-15

    , il est possible de l'atteindre. Les emetteurs alpha et les emetteurs beta purs de faible energie presentent la plus grande difficulte du fait que les charges corporelles de ces nucleides doivent ordinairement etre evaluees par une analyse radiochimique du sang ou des excreta. Les auteurs decrivent les separations radiochimiques qui ont ete mises au point et appliquees au Laboratoire national d*Argonne pour doser rapidement ces emetteurs. Le memoire examine d'autre part certains problemes que pose l'obtention de charges corporelles a partir des taux d'excretion, peu apres l'absorption. Pendant ce laps de temps, l'excretion se modifie rapidement et, pour beaucoup de nucleides importants en l'occurrence, a un taux inconnu. Pour les taux d'absorption tres eleves ou tres bas, il n'est pas necessaire de connaitre immediatement la mesure precise des charges corporelles. Cependant, il existe pour chaque radionucleide une dose d'absorption intermediaire pour laquelle il faut pouvoir -determiner sans trop tarder la charge corporelle avec une precision relative, ce qui permet de decider ou non le traitement. Les auteurs examinent les proprietes et les facteurs qui rendent le dosage des elements osteotropes particulierement difficile dans les cas d'accident. (author) [Spanish] Los metodos aplicables en casos de accidente o en situaciones excepcionales tienen que ser suficientemente rapidos y sensibles para proporcionar resultados en plazos que faciliten el tratamiento eficaz de las personas sobreexpuestas. Los plazos disponibles dependeran, en parte, del numero de individuos irradiados. Si se logra obtener en pocas horas resultados utiles, se habra cumplido la funcion primaria de las mediciones rapidas de la carga corporal, que es la de contribuir en toda la medida de lo posible a reducir los danos debidos .a radionuclidos depositados internamente. Los metodos que se citan a continuacion pueden servir para evaluar la contaminacion interna en casos de accidente: recuento gamma y

  4. A Comparison of Radioisotope Methods for River Flow Measurement; Comparaison de methodes radioisotopiques de mesure du debit des cours d'eau; Sravnenie radioizotopnykh metodov izmereniya rechnykh stokov; Comparacion de los metodos radioisotopicos para medir el caudal de los rios

    Energy Technology Data Exchange (ETDEWEB)

    Clayton, C. G.; Smith, D. B. [Wantage Research Laboratory Atomic Energy Research Establishment Wantage, Berks (United Kingdom)

    1963-08-15

    consequent d'aucune utilite comme indicateur dans la mesure du debit d'un cours d'eau s'il n'est pas employe avec un entraineur; mais avec un entraineur, on observe une amelioration marquee de l'exactitude des resultats. {sup 24}Na et {sup 82}Br n'ont accuse aucune adsorption a des distances bien superieures a celles qui sont necessaires pour assurer une brassage lateral; dans la riviere la plus lente, toutefois, on a note, a plus de 660 m du point d'injection, une certaine diminution de {sup 24}Na. Le memoire contient quelques observations sur la dispersion laterale et longitudinale qui, a une certain degre, influe sur l'application generale des methodes radioisotopiques a la mesure du debit des cours d'eau. Les auteurs parviennent a la conclusion que les trois methodes donnent des resultats satisfaisants. Ils preferent, en fin'de compte, la methode d'echantillonnage continue, car elle donne les resultats les plus exacts pour, la quantite minimum d'indicateur. (author) [Spanish] Los autores han empleado los procedimientos de dilucion, muestreo continuo y recuento total en un estudio comparativo de los metodos radioisotopicos de medicion de caudales fluviales en el arroyo Aylburton, en Gloucestershire, y en los rios Usway Burn y Alwin, en Northumberland. Se trata de tres tios de caracteristicas geologicas diferentes, cuyos caudales oscilan entre 2,5 1/s y 3 m{sup 3}/s. En todos los metodos de medicion de caudales que emplean indicadores, la distancia entre el punto en que se efectua la medicion y el punto en que se anade el indicador tiene que ser suficientemente grande para que se produzca una mezcla lateral completa. Por otra parte, no debe ser excesiva para evitar que la dipersion longitudinal supere cierto valor o que se pierda parte del indicador por adsorcion en el lecho fluvial. La dispersion depende de las caracteristicas hidraulicad de la corriente y es inherente al metodo. Por su parte, la adsorcion depende del indicador elegido y de las caracteristicas geologicas

  5. Improved method for lifetime measurements; Methode perfectionnee de mesure de la duree de vie; Usovershenstvovannyj metod izmereniya vremeni zhizni; Metodo perfeccionado para medir la vida media de los estados de excitacion

    Energy Technology Data Exchange (ETDEWEB)

    Weinzierl, P; Bartl, W [Oesterreichische Studiengesellschaft fuer Atomenergie, Seibersdorf (Austria)

    1962-04-15

    entre los dos detectores. El espectro de impulsos del dispositivo sumador se hace incidir sobre un analizador de un solo canal para la seleccion de la energia deseada. El rayo {gamma} (I) se detecta en otro cristal organico. Los impulsos rapidos de ambos detectores organicos pasan a un convertidor tiempo-altura de impulsos y a un analizador multicanal. Este analizador se hace actuar como puerta mediante una coincidencia lenta entre los discriminadores de alturas de impulsos. (author) [Russian] Izmerenie vremeni zhizni yadra v vozbuzhdennom sostoyanii obychno osnovano na izmerenii otstavaniya odnogo gamma-lucha (II) po otnosheniyu k drugomu gamma-luchu (I) ili k beta-chastitse. Organicheskie stsintillyatory dayut nailuchshuyu razreshayushchuyu sposobnost' po vremeni dlya izmereniya vremeni takogo raspada, no dlya slozhnykh protsessov raspada opredelenie gamma-ehnergii predstavlyaet bol'shoe znachenie i mozhet byt' luchshe vsego dostignuto stsintillyatorami s kristallom NaI(Tl). Dlya sovmestnogo ispol'zovaniya preimushchestv detektorov togo i drugogo tipa gamma-luch (II) prezhde vsego rasseivaetsya v organicheskom kristalle (stil'ben), a rasseyannyj kvant detektiruetsya kristallom Nal(Tl). Dlya osushchestvleniya bol'shikh uglov priemki mezhdu dvumya stsintillyatorami izmerenie gamma-ehnergii dostigaetsya posle slozheniya amplitudy oboikh stsintillyatsionnykh impul'sov. Dlya obespecheniya nadezhnogo dejstviya ustanovki dlya slozheniya postupayushchie iz organicheskogo kristalla impul'sy prokhodyat prezhde vsego cherez strobiruyushchuyu skhemu, kotoraya initsiiruetsya sovpadeniem mezhdu dvumya stsintillyatorami. Spektr impul'sov, postupayushchij iz ustanovki dlya slozheniya, napravlyaetsya v odnokanal'nyj analizator dlya otbora po ehnergii. Gamma-luch (I) detektiruetsya v drugom organicheskom kristalle. Bystrye impul'sy oboikh organicheskikh stsintillyatorov napravlyayutsya v amplitudno-vremennoj preobrazovatel' impul'sov i v mnogokanal'nyj analizator. EHtot analizator

  6. Survey of Pulsed Neutron Source Methods for Multiplying Media; Methodes des Neutrons Pulses Pour l'Etude des Milieux Multiplicateurs; Obzor metodov s ispol'zovaniem istochnikov impul'snykh nejtronov dlya razmnozhayushchej sredy; Estudio Panoramico de los Metodos de Empleo de Fuentes de Neutrons Pulsados en Medios Multiplicadores

    Energy Technology Data Exchange (ETDEWEB)

    Garelis, E. [General Electric Company, Vallecitos Atomic Laboratory, Pleasanton, CA (United States)

    1965-10-15

    -Small-L ). Il discute en outre l'emploi des methodes qui sont fondees sur la reponse a des impulsions pseudoaleatoires et utilisent une correlation entre l'entree et la sortie, pour la determination de la fonction de Green d'un milieu multiplicateur. H montre que les renseignements obtenus par ces methodes sont identiques a ceux fournis par les methodes de la source puisee a repetition, ce qui permet d'appliquer aux premieres les procedes qui ont ete mis au point pour les secondes. (author) [Spanish] En los ultimos afios ha habido dos tendencias principales acerca de la manera mas eficaz de medir la reactividad de parada, empleando fuentes de neutrones pulsados: la primera preconizaba el empleo de metodos tradicionales de medicion con fuentes neutronicas reiteradamente pulsadas, y la segunda propugnaba la aplicacion de metodos basados en una tecnica seudoaleatoria de respuesta a los impulsos, utilizando una correlacion entre los datos de entrada y los de salida. La informacion obtenida con una y otra tecnica es la misma; en teoria, ambos metodos sirven para determinar la funcion de respuesta. Se resefia el desarrollo de las tecnicas de empleo de fuentes de neutrones pulsados aplicadas a sistemas termicos con miras a medir la reactividad, desde los primeros intentos de Sjoestrand hasta el reciente metodo (k{beta}/ Script-Small-L ). Con el metodo usual de empleo de estas fuentes, la propiedad que se procuia determinar es la funcion de Green del conjunto subercritico empleado, es decir, la respuesta del reactor a una fuente de neutrones de funcion delta. El decrecimiento exponencial (e{sup {alpha}t}) de la funcion de Green proporciona una constante de decrecimiento de los neutrones instantaneos que es independiente del espacio. El autor examina los metodos para obtener el valor de la reactividad partiendo de la medida de a, como por ejemplo el metodo de la medicion de la criticidad por neutrones retardados a y el reciente metodo (k{beta}/ Script-Small-L ). Seguidamente examina el

  7. Control Methods Used in the Department of Metallurgy for Structure and Fuel Elements; Methodes de Controle Utilisees au Departement de Metallurgie pour les Elements de Structure et les Elements Combustibles; Metody kontrolya struktury toplivnykh ehlementov v departamente metallurgii; Metodos de Control Utilizados en el Departamento de Metalurgia para los Elementos Estructurales y Combustibles

    Energy Technology Data Exchange (ETDEWEB)

    Destribats, Marie-Therese; Allain, C.; Prot, A.; Thome, P. [Centre d' Etudes Nucleaires de Saclay (France)

    1965-09-15

    reactores indujeron a utilizar y a perfeccionar numersos metodos no destructivos destinados a inspeccionar los distintos materiales que intervienen en la construccion de esos reactores; en particular radiografia y gamma- grafia, metodos ultrasonicos y empleo de corrientes de Foucault.. A continuacion se enumeran las operaciones de control llevadas a cabo durante la construccion de reactores pertenecientes a las familias EdF (grafito-gas) y EL 4 (agua pesada), y de elementos colaminados; se hace hincapie en ciertos aspectos caracteristicos de estos metodos, algunos de los cuales son ya bien conocidos. Familia EdF: metodos ultrasonicos para medir el espesor de las paredes de tubos de uranio o aleacion de uranio ; localizacion de las cavidades en esos tubos por gammagraffa; empleo de medios ultrasonicos para control de los tratamientos termicos a que se someten los tubos; empleo de procedimientos ultrasonicos para buscar fallas (inclusiones, grietas) en las palanquillas y barras con que se elaboran las vainas de Mg-Zr; control de la estanqueidad de los elementos mediante exudacion de helio. EL4: uso de metodos ultrasonicos y corrientes de Foucault para medir espesores de pared en tubos de Zircaloy, sean de fuerza o de guia; empleo de metodos ultrasonicos para inspeccionar tubos de fuerza de Zircaloy y vainas de acero inoxidable; radiografia al vacio de vainas de Be; control de la estanqueidad de barras huecas mediante exudacion de helio. Elementos colimados: medida del espesor de vainas mediante el empleo de corrientes de Foucault pulsadas; verificacion de la posicion del alma en tubos y placas mediante radiografia, recuento gamma y aplicacion de corrientes de Foucault pulsadas; control de la homogeneidad del combustible por recuento gamma; deteccion de defectos en barras de Zr-U mediante procedimientos ultrasonicos y gammagraficos; determinacion de las zonas despegadas en placas, empleando metodos ultrasonicos, corrientes de Foucault pulsadas y medicion de resistividad. Estos

  8. Scanning Study of 700 Livers Evaluation of Existing Diagnostic Procedures; Etude Scintigraphique de 700 Foies (Evaluation des Procedures Actuelles de Diagnostic); Issledovanie pecheni 700 bol'nykh s pomoshch'yu skennirovaniya; Exploracion Hepatica de 700 Pacientes (Evaluacion de los Metodos Actuales De Diagnostico); Exploracion Hepatica de 700 Pacientes (Evaluacion de los Metodos Actuales de Diagnostico)

    Energy Technology Data Exchange (ETDEWEB)

    Czerniak, P. [Radium and Isotope Institute, Government Hospital, Tel-Hashomer (Israel)

    1964-10-15

    regeneracion completa. 3. Despues de una derivacion porta-cava, la imagen del higado es mas pequena y la del bazo mas grande, incluso cuando el estado general es satisfactorio. 4. Los agentes citostaticos pueden ser momentaneamente eficaces para ciertas lesiones hepaticas difusas. 5. Ha ocurrido a veces que al explorar de nuevo una lesion dudosa esta ha aparecido como una lesion macroscopica o ha desaparecido totalmente. Por tanto, la epoca en que se efectua la exploracion puede afectar al diagnostico, . Conclusiones: 1. La exploracion hepatica puede considerarse como metodo muy util para el diagnostico clfnico, morfologico y topografico en hepatopatologia. 2. Los resultados pueden mejorarse: a) utilizando aparatos perfeccionados o tecnicas de exploracion estereoscopica, y b) estableciendo una eficaz colaboracion entre el clinico y el cirujano. (author) [Russian] Provodilis' klinicheskie issledovanija, laboratornye analizy, rentgenograficheskoe obsledovanie i skennirovanie pecheni 700 bol'nyh. Za bol'nymi bylo ustanovleno nabljudenie, i v bol'shinstve sluchaev v konechnom itoge diagnoz podtverdilsja. Takim obrazom byla dana ocenka provedennym issledovanijam. Skennirovanie pecheni proizvodilos' s pomoshh'ju bengal'skoj rozy i polivinilpirolidona, mechennyh zolotom-198 i jodom-131 . Pomimo klassicheskogo AR-metoda dlja opredelenija ra- dioizotopnyh kojefficientov pecheni primenjalis' special'nye metody, takie kak treh ili dvuhploskostnoe stereoskennirovanie i kombinirovannoe izotopnoe issledovanie s pomoshh'ju mechennoj zolotom-198 i jodom-131 bengal'skoj rozy. Bol'nye byli razdeleny na vosem' klinicheskih grupp, i sootvetstvenno proizvodilsja sbor i ocenka diagnosticheskih dannyh. Daetsja kratkoe izlozhenie rezul'tatov jetogo issledovanija. V kazhdoj klinicheskoj gruppe analizy provodilis' otdel'no. Naprimer, v 95%iz 65 sluchaev jehinokokkovoj bolezni byl obnaruzhen ogranichennyj uchastok porazhenija. Rentgenovskoe obsledovanie vyjavilo obizvestvlenie tol'ko v 35%jetih sluchaev

  9. Inventory Methods in a Conversion Plant; Methodes d'Inventaire dans un Etablissement de Transformation; Metody inventarizatsij na predpriyatii po pererabotke yadernykh materialov; Metodos de Inventario en una Planta de Transformacion

    Energy Technology Data Exchange (ETDEWEB)

    Billy, G. [Commissariat a l' Energie Atomique, Paris (France)

    1966-02-15

    inventarios es la de salvaguardar los intereses de la Comision, evaluar la cuantia de las perdidas y controlar las medidas adoptadas para el almacenaje de los desechos. Para el recuento de las existencias el inspector puede efectuar materialmente el inventario, participar en el o comprobarlo. Este ultimo procedimiento es el que da mejores resultados. Las operaciones de recuento, precedidas de una reunion preparatoria para fijar las modalidades, se efectuan en dos tiempos: la comprobacion del inventario ponderal y la comprobacion de la contabilidad fisica. Las cuestiones que pueden plantearse durante el inventario se refieren a las discrepancias en el peso y el contenido, la eleccion del equipo de pesada, los residuos y la evaluacion de las perdidas. Los metodos de inventario no deben diferir de un pais a otro. Parece preferible subrayar las dificultades que se presentan durante las operaciones y estudiar en comun los medios para evitarlas. (author) [Russian] Osnovnymi zadachami inventarizacii javljajutsja: sobljudenie interesov Komissariata; opredelenie razmerov poter'; kontrol' mer, prinimaemyh dlja hranenija othodov. Inspektirujushhee lico mozhet provodit' fakticheskuju inventarizaciju, uchastvovat' v nej ili proverjat' ee. Jetot poslednij metod daet nailuchshie rezul'taty. Operacii po uchetu, kotorym predshestvuet podgotovitel'noe soveshhanie dlja opredelenija sposobov ucheta, provodjatsjav dva jetapa: snachala proverjaetsja nalichie po vesu, azatemdoku mentacija. Voprosy, voznikajushhie v svjazi s inventarizaciej i kasajushhiesja vesa, soderzhanija poko- vok, vybora vesov dlja vzveshivanija, normy othodov i ocenki poter', razreshajutsja otpravite- lem i poluchatelem. Metody inventarizacii v odnom gosudarstve ne dolzhny sil'no otlichat'sja ot takovyh v drugom gosudarstve. Neobhodimo podcherknut' trudnosti, voznikajushhie v processe inven- tarizacii, i zhelatel'nost' otyskanija sovmestnyh putej ih preodolenija. (author)

  10. Multichannel analyzer for nuclear spectrometry with FPGA using Vivado; Analizador multicanal para espectrometria nuclear con FPGA utilizando Vivado

    Energy Technology Data Exchange (ETDEWEB)

    Garcia D, A.; Hernandez D, V. M.; Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98060 Zacatecas, Zac. (Mexico); Ordaz G, O. O.; Ibarra D, S. [Universidad de Cordoba, Campus de Rabanales, Carretera Nacional IV, km 396, 14014 Cordoba (Spain); Bravo M, I., E-mail: angelogarciad@hotmail.com [Universidad de Alcala, Departamento de Electronica, Campus Universitario s/n, 28805 Alcala de Henares, Madrid (Spain)

    2017-09-15

    The different applications of ionizing radiation have made this a very significant and useful tool, in turn can be dangerous for living beings if they are exposed to uncontrolled doses. However, due to its characteristics, cannot be perceived by the five senses, in such a way that in order to know the presence of it, radiation detectors and additional devices are required that allow to quantify and classify it. This is the case of the multichannel analyzer that is responsible for separating the different pulse heights that are generated in the detectors, in a certain number of channels; according to the number of bits of the analog to digital converter. The development or conditioning of nuclear technology has increased considerably due to the demand of the applications; therefore this allows developing systems that cover some commercial requirements, cost and volume in relation to the user needs. The objective of the work was to design and implement an intellectual property core (IP Core) which functions as a multichannel analyzer for nuclear spectrometry. For the IP Core design methodology, its components were created in VHDL hardware description language and packaged in the Vivado design suite, making use of resources such as the ARM processor cores that the Zynq chip contains. Likewise, for the first phase of the implementation, the hardware architecture was embedded in the FPGA and the application for the ARM processor was programmed in C language. For the second phase, the management, control and visualization of the results, a virtual instrument was developed in the LabView programming platform. The data obtained as a result of the development and implementation of the IP Core was observed graphically in a histogram that is part of the aforementioned virtual instrument. (Author)

  11. A telemetria de respostas neurais no sistema de implante coclear multicanal nucleus 24: revisão da literatura

    Directory of Open Access Journals (Sweden)

    Ferrari Deborah V.

    2004-01-01

    Full Text Available A telemetria de respostas neurais (NRT é uma nova técnica disponível no implante coclear Nucleus 24 (Cochlear Corporation que permite o registro do potencial de ação composto eletricamente evocado (ECAP peri ou pós-opertoriamente, utilizando apenas os equipamentos normalmente necessários para a programação do processador de fala do implante coclear. O objetivo deste artigo é descrever o procedimento da NRT e algumas de suas aplicações clínicas e de pesquisa. A literatura relata que a técnica da NRT possui algumas vantagens sobre outros procedimentos objetivos e que as respostas do ECAP podem ser úteis para estimar limiares e níveis de máximo conforto para a estimulação elétrica. Outras pesquisas são necessárias para verificar como estas medidas podem ser utilizadas no estudo das propriedades das estruturas remanescentes do nervo coclear.

  12. A new implementation of multichannel radiochromic film dosimetry; Una nueva implementacion del analisis multicanal para la dosimetria mediante peliculas radiocromicas

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Rodriguez, C.; Martin Martin, G.; Bermudez Luna, R.; Lopez Fernandez, A.; Tores Olombrada, M. V. de

    2014-07-01

    The aims of this paper are to carry out a new implementation of the multichannel radiochromic film dosimetry (Micke A, Lewis D, Yu X. Multichannel film dosimetry with nonuniformity correction. Med Phys 2011;38:2523-34), to quantify the variation in gamma index as compared to the single channel film dosimetry, and to determine if the procedure achieves similar results by means of a different scanner that the one used by Micke et al. Radiochromic EBT2 films and a Microtek 9000 XL scanner were used. Our procedure simplifies the system calibration splitting it into two factors, manufactured batch and digitalization specific. Absorbed dose spatial distributions from an open radiotherapy beam without any modulation and 20 IMRT treatments were determined. Their gamma index maps were calculated and a comparison of the results from single channel and multichannel dosimetry was performed. A 5% mean increase in concordance was obtained by using the multichannel film dosimetry. Our results are similar to those reported by Micke et al. even though we are using a different scanner. (Author)

  13. Comparative Study of the Methods Used for the Computer Resolution of Composite Gamma-Ray Spectra; Etude Comparative des Methodes Utilisees pour la Resolution de Spectres Gamma Complexes au Moyen d'un Ordinateur; Sravnitel'noe izuchenie metodov razresheniya sostavnykh gamma-spektrov pri pomoshchi schetno-reshayushchego ustrojstva; Estudio Comparativo de los Metodos Aplicados para Resolver Espectros Gamma Complejos Mediante Calculadoras

    Energy Technology Data Exchange (ETDEWEB)

    DeHaan, A. Jr.; Leventhal, L.; Benson, P. [Tracerlab, Richmond, CA (United States)

    1965-10-15

    'a resolution; 2. Resolution du pic sans elimination; 3. Etablissement d'un ensemble d'equ'ations lineaires simultanees du meme ordre que le nombre de radionucleides presents dans le melange et solution de ces equations; 4. Evaluation des concentrations non connues par la methode des moindres carres, classique ou ponderee; 5. Combinaison des methodes statistiques et des methodes des moindres carres utilisant la regression lineaire multiple progressive, en s'efforcant d'integrer des processus decisifs dans l'analyse. Pour chaque methode d'analyse appliquee a des melanges de radionucleides, les auteurs fournissent une estimation statistique des erreurs de mesure de la concentration des radionucleides. (author) [Spanish] La resolucion de mezclas complejas de emisores gamma se ha simplificado gracias al empleo de espectrometros gamma muy perfeccionados en asociacion con calculadoras numericas. En la actualidad, los laboratorios pueden en general disponer de estos instrumentos o tener facilmente acceso a ellos. En la memoria se examinan los metodos seguidos en el laboratorio de los autores para determinar la concentracion de cada radionuclido emisor gamma contenido en muestras de precipitaciones radiactivas, y se comparan los resultados obtenidos por los diferentes metodos matematicos aplicables a las muestras compuestas. Los datos proporcionados por las calculadoras se comparan con los resultados obtenidos por analisis radioquimico de la muestra. Se han analizado muestras binarias por los metodos mencionados, operacion que se extendio despues a las mezclas integradas por muchos componentes. Se ha elaborado un metodo de computo que normaliza los espectros gamma para reducir al mfnimo el efecto de la deriva del espectrometro a largo plazo, y representa el espectro segun un sistema de coordenadas, una de las cuales es la energia. Se han investigado los efectos de un 'fotopico imprevisto', de una componente de intensidad cero y de picos superpuestos en la resolucion segun los

  14. Non-Destructive Methods for Determining Burn-Up in Nuclear Fuel; Methodes Non Destructives d'Evaluation du Taux de Combustion dans le Combustible Nucleaire; Metody opredeleniya vygoraniya v yadernom toplive bez razrusheniya obraztsa; Metodos No Destructivos para Determinai el Grado de Combustion de los Elementos Combustibles Nucleares

    Energy Technology Data Exchange (ETDEWEB)

    McGonnagle, W. J. [Illinois Institute of Technology, Chicago, IL (United States)

    1966-02-15

    gamma emis par les matieres radioactives qui se forment au cours du processus de fission, en particulier le spectrometre a cristal courbe, le spectrometre Compton magnetique, le spectrometre Compton a coiencidence et le spectrometre a scintillation. Parmi les autres methodes non destructives, on peut citer l'activation de feuilles, la transmission des neutrons, l'analyse par activation, la mesure des rayonnements gamma de capture et la mesure des neutrons instantanes et differes. Le memoire etudie les principes essentiels des differents appareils et procedes ci-dessus, leur precision et leurs limitations. Le memoire presente des methodes non destructives utilisant les isotopes stables produits au cours du processus de fission. Dans les mesures au moyen de ces isotopes, le schema d'irradiation n'a qu'une importance secondaire et le temps de refroidissement ne joue aucun role. De plus, on dispose de donnees nucleaires plus precises sur les produits stables de la fission. Il semble que les plus utiles de tous les isotopes stables produits au cours du processus de fission soient ceux du zirconium, du molybdene, du ruthenium et du neodyme. Le memoire etudie l'interet de ces methodes d'analyse non destructive. (author) [Spanish] Los metodos no destructivos son de gran utilidad para medir cuantitativamente el grado de combustion. El metodo ideal seria el que no requiriese datos especiales sobre los espectros neutrtfni- cos, las irradiaciones precedentes o el tiempo de enfriamiento. Los elementos combustibles irradiados llevan en cierto modo el registro de su grado de combustion. Este registro consiste en el conjunto de los isotopos radiactivos y estables resultantes del proceso de fision. Desgraciadamente, tanto con los metodos no destructivos como con los destructivos el espectro neutronico, las irradiaciones precedentes y el tiempo de enfriamiento influyen sobre dicho registro. Analogamente, la falta de datos nucleares precisos tales como las secciones eficaces nucleares

  15. Uses and updating of the Benders method in the integer-mixed programming in the planning of the electric power systems expansion; Usos y actualizacion del metodo de Benders en la programacion entera-mixta y en la planeacion de la expansion de los sistemas electricos de potencia

    Energy Technology Data Exchange (ETDEWEB)

    De la Torre Vega, Eli

    1997-04-01

    of some potential improvements that the proposed method has. [Espanol] En el primer capitulo se presenta la deduccion de los cortes de Benders partiendo de las propiedades de la dualidad. Tambien se presentan las propiedades de los cortes de Benders asi como el algoritmo inicial de Benders para resolver cualquier problema de programacion lineal entera-mixta. En el segundo capitulo, se presenta el problema de la planeacion de la expansion de los medios de generacion y transmision en un sistema electrico de potencia, las distintas estructuras de la programacion matematica a que da lugar y como se puede adaptar el metodo de Benders a estas. En el tercer capitulo se presentan las aportaciones teoricas de este trabajo: a) Como inicializar el problema maestro para aprovechar la experiencia adquirida despues de haber resuelto un problema similar, de modo que se pueda resolver mas eficientemente, la sucesion de problemas de programacion lineal entero-mixtos que surgen al resolver el problema de la planeacion de la expansion de los medios de generacion y transmision en un sistema electrico de potencia. b) Como generar un problema maestro cuya solucion optima continua corresponda al optimo continuo del problema entero-mixto, de modo que la busqueda de soluciones enteras se realice en la vecindad del optimo continuo. c) Como generar una solucion entera, cercana al optimo continuo del problema entero-mixto, que tenga mucha probabilidad de ser factible, y que quizas sea la solucion optima entera, en un tiempo menor al que se requiere para resolverlo en forma exacta. Ademas, se presentan otras ideas que se le pueden incorporar al metodo de Benders. A fin de mostrar la efectividad de las ideas propuestas, en el capitulo 4 se presentan los resultados obtenidos al resolver varios problemas usando: 1. El metodo de Benders in actualizacion, 2. El metodo de Ramificacion y Acotamiento, 3. La actualizacion de Benders al agregar restricciones y 4. La actualizacion de Benders al considerar

  16. Il metodo mitico e i cattivi pensieri

    Directory of Open Access Journals (Sweden)

    Elio Franzini

    2012-05-01

    Full Text Available Moving from a definition of his « mythical method», the essay aims to outline the so-called «Philosophy of Art» of Paul Valéry. It sketches a portrait of the French author as an authentic philosopher of phenomenology able to define in a non-abstract way what must be intended with «aesthetics».

  17. Le narrazioni come metodo di indagine sociologica

    Directory of Open Access Journals (Sweden)

    Rita Bichi

    2012-04-01

    Full Text Available L'incontro trentino ha dimostrato l'interesse crescente dei giovani sociologi per lo sviluppo dei metodi narrativi e la capacità che questi hanno di essere efficaci nell'analisi di svariati temi, dai racconti di malattia alle narrazioni identitarie, dallo studio di lavoro e organizzazioni a quello delle migrazioni, di genere e memoria. Tuttavia, l'interesse della sociologia italiana va visto in un quadro di sviluppo più ampio a livello europeo e americano dove, a partire dagli anni '90, l'intervento di alcuni autori come Lyotard, Bruner e Macintyre, ha sancito quella che alcuni autori hanno definito svolta narrativa. La sociologia, infatti, tende sempre più a valorizzare la narrazione come processo di conoscenza peculiare che è attivato costantemente nella vita quotidiana; la "rivoluzione" risiede nel fatto che la narrazione diventa oggetto della sociologia e la disciplina stessa valorizza il suo uso sia come strumento di indagine scientifica, sia come modo di conoscere che come modo di comunicare, rivendicando la legittimità scientifica all'ascolto della parola diretta degli individui coinvolti all'interno delle ricerche di stampo sociologico.

  18. Il metodo storico nella critica testuale

    OpenAIRE

    Giangrande, Giusseppe

    2008-01-01

    Se ofrecen ejemplos de cómo es posible explicar por medio de un enfoque histórico pasajes controvertidos de autores griegos y latinos. Passages of Greek and Latin authors which many a critic cannot understand can often be explained by placing them in the proper historical perspective.

  19. Recent Radiochemical Procedures for Bio-Assay Studies at Trombay; Methodes Radiochimiques d'Analyse Biologique Employees a Trombay; Nedavno razrabotannye v trombee radiokhimicheskie metody dlya biologicheskikh issledovanij; Regientes Metodos Radioquimicos Aplicados al Analisis Biologico en Trombay

    Energy Technology Data Exchange (ETDEWEB)

    Kamath, P. R.; Bhat, I. S.; Rudran, Kamala; Iyengar, M. A.R.; Koshy, Elizabeth; Waingankar, Urmila S.; Khanolkar, Vasanti S. [Health Physics Division, Atomic Energy Establishment Trombay, Bombay (India)

    1964-10-15

    travaux accomplis au laboratoire d'analyses biologiques depuis 1958. (author) [Spanish] El laboratorio de analisis biologicos de Trombay efectua anualmente cerca de dos mil analisis de orina para determinar diferentes radionuclidos, siendo los isotopos de mayor interes el {sup 232}Th, {sup 228}Th, {sup 226}Ra, {sup 224}Ra, {sup 228}Ra, U natural, productos de fision y {sup 239}Pu, asip como el {sup 60}Co, {sup 32}P, {sup 131}I, {sup 32}P, {sup 137}Cs, {sup 3}H, {sup 90}Sr, etc. El analisis rapido de un gran numero de muestras de baja actividad exige el perfeccionamiento de tecnicas especiales, sobre todo cuando se desea un alto grado de especificidad, unido a un elevado rendimiento. La' orina presenta una matriz muy complicada, con una elevada proporcion de sustancias organicas complejantes y contenido variable de sales. Los procedimientos de calcinacion por via humeda exigen un tiempo considerable y resultan engorrosos cuando se han de destruir muestras de aproximadamente 1 a 1,5 l. El trabajo deseribe algunos metodos recientemente desarrollados en el laboratorio de los autores y proporciona detalles de estudios sobre indicadores que han intervenido en el desarrollo de aquellos metodos. Radio-228: Se mide el mesotorio contenido en la orina despues de separar el {sup 228}Ac en equilibrio radiactivo. El radio presente en la orina se coprecipita con BaSO{sub 4}, teniendose en cuenta que sigue formandose {sup 228}Ac. El precipitado se disuelve en acido perclorico despues de anadir como portadores Pb, Bi y La. Los sulfatos insolubles se precipitan con H{sub 2}SO{sub 4} diluido y el {sup 228}Ac que permanece en solucion, despues de ser arrastrado con F{sub 3}La, se somete a recuento de actividad beta y se comprueba la disminucion de actividad. La cantidad de {sup 228}Ra se calcula a partir de la actividad observada en el {sup 228}Ac despues de introducir la oportuna correccion para tener en cuenta la desintegracion y el rendimiento de la recuperacion quimica. Torio: El trabajo

  20. Proposed method for the hydraulic design of ski-jump energy dissipators in dam spillways considering the occurrence of scour holes downstream of the structure; Metodo propuesto para el diseno hidraulico de trampolines empleados como disipadores de energia en aliviaderos para presas, considerando la ocurrencia del cono de socavacion al pie del mismo

    Energy Technology Data Exchange (ETDEWEB)

    Pardo-Gomez, Rafael [Centro de Investigaciones Hidraulicas (Cuba)

    2008-04-15

    Ski-jump energy dissipators are widely used in hydraulic engineering because of their well-known effectiveness. Nevertheless, some uncertainty exits associated with the dimensions of the scour hole appearing downstream of the structure. This paper presents a new method for solving this problem. This method includes spillway stability checking as part of the design process and also stability checking of any other construction near the energy dissipation zone. [Spanish] Los disipadores de energia tipo trampolin tienen amplia utilizacion en la practica de la ingenieria hidraulica por su probada eficacia; sin embargo, su diseno esta sujeto a cierto grado de incertidumbre en cuanto a la prediccion de las dimensiones del cono de socavacion que habra de producirse aguas abajo de la estructura. En el presente trabajo se muestra un metodo novedoso, mediante el cual el autor soluciona el aspecto antes referido, toda vez que se incluye como parte del proceso de diseno la comprobacion de la estabilidad del propio aliviadero o de cualquier otra obra cercana a la zona de disipacion de energia.

  1. Double-Sampling Method for Carrying Out Quality Control of a Fabrication Process; Methode du Double Echantillonnage pour le Controle de la Qualite d'un Procede de Fabrication; Metod dvukh obraztsov dlya osushchestvleniya kontrolya za kachestvom v protsesse izgotovleniya; Metodo de Muestreo Doble para el Control de Calidad de un Proceso de Fabricacion

    Energy Technology Data Exchange (ETDEWEB)

    Cerrolaza, J. A.; Lago, A.; Montojo, Rosa M. [Junta de Energia Nuclear, Madrid (Spain)

    1966-02-15

    taille des echantillons et le degre de controle sont determines en fonction des risques inherents a la premiere et a la deuxieme condition. Bien que cette methode soit applicable, elle est fort peu pratique quand il s'agit de controler des pieces de reacteurs, car les echantillons qu'elle exige sont de dimensions excessives. Le memoire expose une methode analogue a celle de Cave mais qui consiste a etablir un double echantillonnage dans lequel la taille moyenne de l'echantillon est beaucoup plus reduite. (author) [Spanish] La fabricacion de componentes que han de ser empleados en reactores nucleares presenta dos caracteristicas fundamentales que condicionan el proceso: la exigencia de una calidad muy elevada que limita a valores muy bajos el porcentaje de piezas defectuosas admisibles, y el coste muy alto de cada uno de los componentes. Estas dos condiciones obligan a que el control durante la fabricacion posea una curva de operacion con potencia muy elevada, y, por otra parte, a que el numero de piezas destruidas en cada inspeccion sea un pequeno como se pueda, siempre que se cumpla la condicion anterior. Los metodos usuales de control, basados en fijar el riesgo de primera especie, no son aplicables, ya que en general su eficacia no es suficiente. Cave ha desarrollado un metodo en que, tanto el tamano de las muestras como los limites de control, se fijan en funcion de los riesgos de primera y segunda especie. Este metodo, si bien es aplicable, resulta poco practico en el control de componentes para reactores, ya que se necesitan muestras de un tamano excesivamente grande. En el presente trabajo se desarrolla un metodo semejante al de Cave, pero en el que se establece un muestreo doble, con lo que el tamano medio de la muestra es mucho mas reducido. (author) [Russian] Pri izgotovlenii komponentov dlja ispol'zovanija v reaktorah reshajushhee znachenie imejut dva osnovnyh faktora, a imenno: neobhodimost' obespechit' ochen' vysokoe kachestvo, dopuskajushhee lish' ochen

  2. Automatic Inspection of Co-Laminated Elements; Controle Automatique d'Elements Colamines; Avtomaticheskij kontrol' ul'trazvukom sovmestno prokatannykh ehlementov; Metodo para la Verificacion Automatica de Elementos Colaminados

    Energy Technology Data Exchange (ETDEWEB)

    Destribats, Marie-Therese [Centre d' Etudes Nucleaires de Saclay (France); Dory, J. [Realisations Ultrasoniques Meaux (S. et M.) (France)

    1965-09-15

    'un disque rotatif. Chaque traducteur est mis en service tous les 1/6 de tour par l'intermediaire de relais commandes par des secteurs aimantes. De la sorte, le pinceau ultrasonore decrit sur la surface de la plaque une serie d'arcs de cercle jointifs. La quantite d'energie transmise a travers la plaque est mesuree avec precision en chaque point. Le resultat de la mesure est applique a un enregistreur special qui donne une reproduction en vraie grandeur de l'element examine (le papier de l'enregistreur est de type ordinaire; l'inscription s'effectue au moyen de papier carbone). Sur l'enregistrement obtenu, les defauts apparaissent sous forme de taches foncees. L'appareillage peut fonctionner, soit en tout ou rien avec un seuil de marquage predetermine, soit en demi-teintes. Les traducteurs, dont la frequence peut varier de 3 a 15 MHz, sont excites par des impulsions breves. Les traducteurs utilisies, en titanate de baryum, ont un diametre de 3 mm. Le pas d'exploration est variable de 0,3 a 0,6 mm, la vitesse lineaire etant de 5 a 20 mm par seconde. L'ensemble peut recevoir des elements ayant les dimensions maximales suivantes: largeur 150 mm, longueur 2000 mm, epaisseur 25 mm. Les essais effectues jusqu'a ce jour ont permis de determiner des zones decollees de 0,5mm diametre dans de elements de 2 mm d'epaisseur. (author) [Spanish] Se describe en esta memoria un aparato automatico destinado a verificar, por un metodo ultrasoniso, la calidad de las vainas fabricadas con elementos colaminados. Estos elementos movidos por rodillos pasan bajo el haz ultrasonico sumergidos en una cuba de acero inoxidable llena de agua. Un reflector auxiliar permite utilizar los mismos transductores para la emision y la recepcion. La exploracion de las placas se lleva a cabo mediante seis transductores dispuestos en la periferia de un disco rotativo. Los transductores entran en funcion uno tras otro, cada 1/6 de vuelta, por intermedio de un sistema reles accionados por sectores imanados. De esta

  3. Neutron Investigation of Magnon Spectrum in Haematite; Etude du Spectre de Magnons dans l'Hematite, au Moyen des Neutrons; Nejtronnoe issledovanie spektra magnona v gematite; Estudio, por Metodos Neutronicos, del Espectro de Magnones en la Hematita

    Energy Technology Data Exchange (ETDEWEB)

    Dimitrijevic, Z.; Rzany, H.; Todorovic, J.; Wanic, A. [Institute for Nuclear Physics Cracow (Poland)

    1965-04-15

    -Sign y 126 Degree-Sign , respectivamente. Un acuerdo satisfactorio entre la teoria y los datos experimentales disponibles se tiene cuando SJ{sub 1} = SJ{sub 2} = 5,1 meV. Ademas de la rama magnonica acustica, los calculos han revelado la existencia de una rama optica, pero el estudio de esta no pudo llevarse a cabo por el metodo de difraccion neutronica. (author) [Russian] byli provedeny v Vincha na reaktore RA s ispol'zovaniem kristallicheskogo nejtronnogo spektrometra. Rassejanie monohromaticheskih nejtronov ({lambda} = 1.314A) proizvodilos' na krupnom monokristalle gematita ({alpha}-Fe{sub 2}O{sub 3}). Issledovalis' uglovye raspredelenija neuprugo rassejannyh nejtronov. Dlja rjada razlichnyh nepravil'nyh uglov kristalla AO byla izmerena shirina G puchka rassejannyh nejtronov (tak nazyvaemogo konusa rassejanija). Jetot konus rassejanija byl pripisan javleniju poverhnostnogo rassejanija magnona vokrug tochki obratnoj reshetki [1,1,1] . Dlja rjada skorostej magnona byla rasschitana i sravnena s jeksperimental'nymi tochkami zavisimost' G ot nepravil'nogo ugla. Ustanovleno, chto velichina skorosti v napravlenii [111] ravna 25,5 11,0 km/sek. Byla obnaruzhena strukturnaja anizotropija dispersionnogo sootnoshenija magnona. Bylo najdeno, chto skorost' javljaetsja bolee vysokoj v napravlenijah rasprostranenija parallel'nyh osi [111] i chto kachestvenno ona horosho soglasuetsja s bolee rannimi izmerenijami (Riste i dr.) dajushhimi v = 38km/sek. Obnaruzhit' v akusticheskoj oblasti jenergii magnona sushhestvovanie razryva jenergeticheskoj krivoj Eg ne udalos'. Bylo rasschitano, chto velichina E dolzhna byt' nizhe 1 Mjev. Pri pomoshhi formalizma Uollase byli rasschitany dispersionnye sootnoshenija magnona v gematite. Pri jetom ishodili ije predpolozhenija, chto sushhestvujut dva ne stremjashhihsja k nulju integrala obmena J{sub 1} i J{sub 2}. J{sub 1} i J{sub 2} oznachajut svjaz' sverhobmennoj jenergii mezhdu spinami sosednih ionov zheleza, svjazannyh ionom kisloroda. Ugly svjazi

  4. An Appraisal of Analytical Methods for Plutonium and their Applications to the Analysis of Nuclear Materials; Evaluation des Methodes Analytiques de Dosage du Plutonium et de Leur Application a l'Analyse des Matieres Nucleaires; Otsenka analiticheskikh metodov opredeleniya plutoniya i ikh primenenie dlya analiza yadernykh materialov; Metodos Analiticos de Determinacion del Plutonio y su Empleo en el Analisis de Materiales Nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Milner, G. W.C.; Phillips, G. [Atomic Energy Research Establishment, Harwell, Berks. (United Kingdom)

    1966-02-15

    respectifs de la dissolution dans des melanges d'acides mineraux courants et de la dissolution faisant appel a des procedes de fusion, avec des exemples a l'appui. Les auteurs decrivent aussi les procedes utilises et les resultats obtenus, pour l'analyse des alliages Pu-U, Pu-Ce-Co et Pu-U-Mo, des oxydes et carbures de Pu-U, et des cermets de carbure de Pu-U contenant Fe, Mo et Cr. Ces matieres sont l'aboutissement de recherches metallurgiques destinees a mettre au point des combustibles nucleaires. (author) [Spanish] Para determinar el contenido de plutonio de los materiales nucleares existen diversos metodos. Si se trata de cantidades del orden del miligramo se pueden emplear la espectrofotometria diferencial por el color del Pu (III), la gravimetria basada en el PuO2{sub ,} si recuento gamma y metodos de oxidorreduccion como las valoraciones potenciometricas o amperimetricas y la culombiometria de potencial controlado. Si se trata de microgramos son preferibles el recuento alfa, la dilucion isotopica o las tecnicas polarograficas. Teniendo en cuenta que unos metodos son mas adecuados que otros para ciertos tipos de muestra, el analista tiene que resolver un dificil problema de seleccion a fin de obtener ios mejores resultados posibles. Los autores exponen las ventajas y las limitaciones puestas de manifiesto por los anos de experiencia en la A.E.R.E. y formulan observaciones acerca de la exactitud y la precision de los metodos, su sensibilidad y otras cuestiones de especial interes. Como algunos de esos metodos exigen la separacion previa del plutonio, los autores estudian el empleo de las tecnicas de intercambio anionico y de cromatografia en fase inversa, y en particular su conveniencia para el analisis de muestras radiactivas. Examinan los muchos problemas que han surgido al analizar por estos metodos, aleaciones, productos ceramicos y cermets de plutonio en diversos sistemas que contenian uranio, torio, hierro, cromo, molibdeno, cerio y cobalto. La memoria trata

  5. The Application of Various Nondestructive Testing Methods to Fuel Elements of the Orgel Type; Application des Differentes Methodes d'Essais Non Destructifs aux Elements Combustibles du Type Orgel; Primenenie razlichnykh nedestruktivnykh metodov ispytanij k toplivnym ehlementam tipa ''orgel''; Aplicacion de Distintos Metodos de Ensayo No Destructivo a los Elementos Combustibles de Tipo Orgel

    Energy Technology Data Exchange (ETDEWEB)

    Bonnet, P.; Jansen, J. [EURATOM, C.C.R., Ispra (Italy)

    1965-09-15

    methode a un capteur montre quelles sont les limites d'utilisation de ces deux methodes. Defauts transversaux; La methode a un capteur appliquee a cette recherche fait l'objet d'une breve description. Entrainement mecanique: Le memoire fait etat d'un banc mecanique, type laboratoire, pour la recherche des criteres d'essais et d'un banc de passage des tubes, de type semi-industriel, pour l'examen en continu avec enregistrement des defauts. Les difficultes rencontrees et les moyens misenceuvrepoury remediersont evoques. c) Tests par radiographie. Cette methode fera l'objet d'un memoire special; seuls sont indiques les resultats obtenus sur tubes de force ou sur tubes de gaines. d) Test divers Les test finaux sur elements combustibles complets peuvent se resumer en deux parties. Tests d'etancheite au moyen du test a l'helium developpe par la SOGEV. Un dispositif permet d'examiner simultanement 4 ou 6 elements combustibles ou separement 2 ou 3. Tests classiques de radiographie; l'accent est mis plus particulierement sur l'etude des soudures; on donne la marge des conditions experimentales pour obtenir une bonne definition. En conclusion, les auteurs presentent un projet de chaine de controle semi-industrielle avec les differentes possibilites de traitements et essaient de degager une certaine philosophie des tests non destructifs appliques aux elements combustibles. (author) [Spanish] La memoria presenta los distintos metodos empleados para deteccion de fallas (de tipo dimensional o estructural) en vainas de elementos combustibles. Los autores describen, asimismo, los ensayos finales con elementos combustibles completos, en particular radiografia de las soldaduras y pruebas de estanqueidad. Este tema se ha tratado ya en forma parcial. El estudio de las caracteristicas dimensionales de las vainas lisas de SAP (producto de aluminio sinterizado) ha sido objeto de trabajos bastante avanzados. La memoria examina en particular los siguientes temas: 1. Medicion de diametros internos

  6. Industrial Ultrasonic Inspection of Stainless-Steel Claddings for the EL4 Reactor; Controle Industriel par Ultrasons des Gaines en Acier Inoxydable du Reacteur EL4; Promyshlennyj kontrol' obolochechnykh trub iz nerzhaveyushchej stali reaktora dlya EL4 s pomoshch'yu ul'trazvukovogo metoda; Metodos Ultrasonicos para Control Industrial de las Vainas de Acero Inoxidable del Reactor EL4

    Energy Technology Data Exchange (ETDEWEB)

    Prot, A. C.; Foulquoer, H. E.; Peyrot, J. P. [Centre d' Etudes Nucleaires de Saclay (France)

    1965-09-15

    del metodo a utilizar representa un proceso delicado, cuyas consideraciones fundamentales se exponen en el presente trabajo. Una vez elegido el metodo y puesto a punto en el laboratorio, surgen dos nuevos problemas: Transposicion a escala industrial. Necesidad de tener siempre presente la calidad que puede alcanzarse en la industria, en relacion con normas de aceptacion definidas de manera mas o menos arbitraria. En la practica, ello obliga a realizar un estudio estadistico sobre partidas de tubos de diversos origenes y clasificarlos teniendo en cuenta umbrales de aceptacion de distintos grados de severidad. Como se ve en el trabajo, el numero de tubos a controlar es muy superior al previsto inicialmente. Este hecho indujo a estudiar una maquina de control automatico, capaz de satisfacer al mismo tiempo las exigencias de la cantidad y las propias del tipo de control seleccionado; estas ultimas son por lo general de orden mecanico y requieren una construccion especialmente esmerada. El conjunto de estas consideraciones llevo a concebir una maquina capaz de satisfacer sin dificultad las necesidades de una cadena de fabricacion'de elementos combustibles. Las posibilidades de esta maquina estan estrechamente ligadas a las caracteristicas del material descontrol escogido, sobre todo al rendimiento de los circuitos electronicos correspondientes a los aparatos de control por metodos ultrasonicos y al de los transductores utilizados. Se deduce del presente estudio, por otra parte, que el material corriente no responde al problema sino de manera muy imperfecta, y que se debe encarar desde ya el proyecto de un aparato especial para este tipo de control. (author) [Russian] Uluchshenie rabochih harakteristik reaktorov trebuet primenenija tshhatel'no razrabotannyh i strogo kontroliruemyh materialov. Odnim iz aspektov jetogo kontrolja javljaetsja kachestvo ispol'zuemyh pokrytij dlja trub, mehanicheskoe sostojanie kotoryh predstavljaet soboj sushhestvennyj faktor rentabel

  7. The Role of Non-Destructive Testing in the Los Alamos Reactor Programme; Role des Essais Non Destructifs dans le Programme de Reacteurs de los Alamos; Rol' nedestruktivnykh ispytanij materialov v Los-Alamosskoj reaktornoj programme; Papel de los Metodos de Ensayo No Destructivo en el Programa de Reactores de Los Alamos

    Energy Technology Data Exchange (ETDEWEB)

    Tenney, G. H. [University of California, Los Alamos Scientific Laboratory, Los Alamos, NM (United States)

    1965-10-15

    temperature UHTREX, actuellement en construction, on a etudie par microiadiogiaphie et au moyen de microscopes electroniques des grains de carbure d'uranium enrobes de carbone pyrolytique, d'un diametre de 150 {mu}m, pour evaluer la translocation de l'uranium en fonction de la temperature. On determine la quantite et l'uniformite de la charge d'uranium dans les elements au graphite d'UHTREX au moyen de compteurs a scintillation specialement concus. Environ 90% des travaux effectues a ce sujet n'ont encore fait l'objet d'aucune publication. (author) [Spanish] El Laboratorio Cientifico de Los Alamos, explotado por la Universidad de California por encargo de la Comision de Energia Atomica de los Estados Unidos, viene ocupandose desde hace mas de veinte afios del proyecto, diseno y construccion de reactores nucleares de cuatro tipos generales; a saber, de investigacion, de potencia, de propulsion espacial y para conjuntos criticos. El llamado Grupo de ensayos no destructivos colabora practicamente en todas las actividades y proyectos del laboratorio. En la presente memoria se exponen algunos de los metodos de ensayo no destructivo y sus aplicaciones, establecidos para uso en el programa de reactores. El programa LAPRE (Los Alamos Power Reactor Experiment) se basa en el empleo de una solucion de fosfato de uranio a alta temperatura. La solucion es muy corrosiva y todas las piezas que entren en contacto con ella deben ir revestidas de oro. Durante el proceso de produccion de chapa de oro laminada a partir de lingotes, se han utilizado procedimientos radiograficos especiales para inspeccionar el metal. Las juntas soldadas se examinaron del mismo modo, y ademas se establecio un metodo para comprobar la presencia de impurezas incrustadas en la superficie de la chapa de oro. El concepto fundamental en que se basa el programa LAMPRE (Los Alamos Molten Plutonium Reactor Experiment) es la utilizacion como combustible de plutonio metalico liquido en vez de solido. El combustible esta

  8. New processing techniques for radioisotopes at Oak Ridge National Laboratory; Production de radioisotopes: nouvelles techniques employees au Laboratoire national d'Oak Ridge; Novye tekhnologicheskie metody polucheniya radioizotopov v Okridzhskoj natsional'noj laboratorii; Nuevos metodos de preparacion de radioisotopos aplicados en el Oak Ridge National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Butler, T A; Lamb, E; Rupp, A F [Oak Ridge National Laboratory, Oak Ridge, TN (United States)

    1962-01-15

    une activite de 235 c/g. La poudre a ete comprimee en pastilles, que l'on a ensuite agglomerees pour leur donner une consistance ceramique. Le prometheum-147 a ete produit en quantites de l'ordre du kilocurie par combinaison des techniques de precipitation et d'echanges d'ions. Un procede d'extraction par solvant pour separer le prometheum-147 d'autres terres rares a ete experimente sur de tres faibles quantites. Quelques grammes de technetium-99 ont ete recuperes dans les produits de fission des effluents par precipitation et extraction par solvant combinees. Le technetium avait une purete chimique superieure a 99,9% et une purete radiochimique superieure a 99,99%. La purification du strontium-90 par elimination des contaminants les plus importants, a l'aide d'un systeme d'extraction continu par solvant, a ete demontree sur de tres petites quantites. En partant d'un produit contenant 95% de calcium inerte, on a obtenu du strontium a 98% de purete. On a ensuite traite le strontium-90 pour obtenir des elements ceramiques de titanate de strontium. (author) [Spanish] Entre los adelantos mas recientes introducidos en el programa de preparacion de radioisotopos del Oak Ridge National Laboratory se cuenta el desarrollo de nuevos metodos y el mejoramiento de procedimientos ya establecidos para la obtencion de cerio-144, promecio-147, tecnecio-99 y estroncio-90. Se ha producido experimentalmente cerio-144 en escala de los kiloeuries. Se recupero mas del 98% de cerio con una pureza superior al 99%. Este cerio se siguio purificando hasta obtener oxido de cerio puro en forma pulverulenta de actividad especifica igual a 235 e/g. Este polvo se comprimio en pastillas y se sinterizo para obtener un material ceramico denso. El promecio-147 se obtuvo en cantidades de kiloeuries aplicando un metodo combinado de precipitacion e intercambio ionico. Se ensayo la extraccion de vestigios de elementos con disolventes para separar el promecio-147 de otras tierras raras. Gracias a una

  9. 3m Vacuum Ultraviolet Spectrometer with Optical Multichannel Detector; Espectrometro de ultravioleta de vacio de 3m provisto de sistema de deteccion optical multicanal

    Energy Technology Data Exchange (ETDEWEB)

    Martin, P; Peraza, C; Blanco, F; Campos, J

    1993-07-01

    This paper describes the design and the performance of a normal incidence vacuum ultraviolet spectrometer, for the 300-2400 A spectral range. It is provided with a multichannel detection system. The monochromator is original design and it has been built at CIEMAT. It is equipped with a 3 m concave holographic grating with 2400 grooves/mm. The multichannel detector consists of a windowless double microchannel plate / phosphor screen image intensifier, coupled by fiber optic to a 1024 elements self-scanning linear photodiode array. The output from the array is digitized by a 12-bit analog to digital converter and stored in a computer, for its later analysis. The necessary software to store and display data has been developed. (Author) 18 refs.

  10. A new Implementation of the multi-channel analysis in the dosimetry through radiochromic films; Una nueva implementacion del analisis multicanal en la dosimetria mediante peliculas radiocromicas

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Rodriguez, C.; Martin Martin, G.; Bermudez Luna, R.; Lopez Fernandez, A.; Torres Olombrada, M. V. de; Garcia Canibano, T.; Caballero Guerra, P.

    2013-07-01

    The objectives of this study are to implement multi-channel analysis algorithm using open source tools, extend the application of the same to a scanner other than the supported by Micke, generate maps of dose absorbed in compatible format with the PTW Verisoft quality control program and to quantify the improvement in the results of the gamma index as to what would be obtained by applying a conventional single-channel analysis. (Author)

  11. Development and implementation of own software for dosimetry multichannel film; Desarrollo e implementacion de un software propio para la dosimetria multicanal con pelicula radiocromica EBT2

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez Feltstrom, D.; Reyes Garcia, R.; Luis Simon, F. J.; Carrasco Herrera, M.; Sanchez Carmona, G.; Herrador Cordoba, M.

    2013-07-01

    The objective of this work is to develop its own software for multichannel film dosimetry Radiochromic EBT2. Compare the results obtained with its use in multichannel and single-channel dosimetry. Check that the multi-channel dosimetry eliminates much of the artifacts caused by dirt, fingerprints, scratches, etc. Radiochromic in film and scanner devices. (Author)

  12. Projeto e desenvolvimento de um sistema multicanal de biotelemetria para detecção de sinais ECG, EEG e EMG

    OpenAIRE

    Caparelli, Thiago Bruno

    2007-01-01

    O emprego de novas técnicas na aquisição, processamento e análise de sinais bioelétricos, têm contribuído significativamente para o melhoramento dos processos de monitoramento fisiológico de indivíduos. Porém, em muitas situações deseja-se registrar aqueles sinais concomitantemente com monitoração e execução de movimentos livres, como durante corridas e saltos. A forma convencional de registro utiliza, normalmente, conexões de fios aos indivíduos, dificultando sobremaneira a ...

  13. The Control of Fast Reactors: Current Methods and Future Prospects; Controle des Reacteurs a Neutrons Rapides. Methodes Actuelles et Perspectives d'Avenir; Upravlenie reaktorami na bystrykh nejtronakh. sushchestvuyushchie metody i dal'nejshie perspektivy; Control de Reactores Rapidos: Metodos Actuales y Perspectivas

    Energy Technology Data Exchange (ETDEWEB)

    Loewenstein, W. B. [Argonne National Laboratory, IL (United States)

    1964-06-15

    examina los actuales mecanismos de control de los reactores de neutrones rapidos. En la medida de lo posible aprovechan el control por medio de fugas neutronicas. Si este metodo no es aplicable se suele recurrir al control por desplazamiento de los materiales del cuerpo. Igualmente se recurre a un control limitado utilizando un absorbente. Ninguno de estos metodos presenta ventajas considerables cuando se aplica a los'grandes reactores de potencia regeneradores, a menos que la razon interna de regeneracion (del cuerpo) sea muy elevada. Se requerira mucha habilidad para utilizar metodos de control basados en el empleo de un absorbente o en el desplazamiento espectral sin afectar en grado apreciable la economia neutronica deseada y a menudo necesaria. El autor cita algunos resultados preliminares obtenidos con sistemas perfeccionados. La reactividad de control viene determinada por los requisitos relativos a la parada del reactor, al ciclo del combustible (exceso de reactividad) y, en menor medida, por la realimentacion dominante. Pueden especificarse perfectamente los requisitos relativos al exceso de reactividad para un ciclo de combustible determinado, pero esos requisitos varian de modo considerable en otros sistemas similares que funcionen con distintos ciclos de combustible. A partir de ciertos limites, pueden fijarse casi arbitrariamente les requisitos relativos al exceso de reactividad. Sin embargo, existen algunas consideraciones generales que rigen la determinacion de este parametro. Se tienen en cuenta dichas consideraciones al examinar la reactividad de control en los actuales reactores de neutrones rapidos comparandola a la cantidad realmente necesaria para el funcionamiento de reactores de potencia regeneradores y neutrones rapidos. El autor cita parametros tipicos de potencia y de realimentacion en funcion de la temperatura a fin de determinar su influencia en los requisitos relativos a la reactividad de control. Los metodos utilizados para predecir la

  14. Electrochemical performance in the hydrogen evolution reaction of Ni-TR (TR= La, Ce) materials synthesized using the solid state reaction method; Desempeno electroquimico en la reaccion de evolucion de hidrogeno de materiales de electrodo Ni-TR (TR = La, Ce) sintetizados por el metodo de reaccion de estado solido

    Energy Technology Data Exchange (ETDEWEB)

    Torres-Huerta, A. M.; Dominguez-Crespo, M. A.; Ramirez-Meneses, E.; Yanez-Zamora, C. [CICATA, IPN, Altamira, Tamaulipas (Mexico); Avila-Garcia, I. [IPN, ESIQIE, UPALM, Mexico, D.F. (Mexico)]. E-mail: mdominguezc@ipn.mx; adcrespo2000@yahoo.com.mx

    2009-09-15

    relacionados con su operacion. El material de electrodo con mayor electroactividad es el Pt, pero debido a su costo elevado se han tenido que buscar electrocatalizadores alternativos con un balance entre costo y actividad. Uno de los materiales que mas se ha utilizado es el Niquel en conjunto con algunas de sus aleaciones. Este material ha demostrado un buen desempeno utilizando bajos sobrepotenciales en reacciones tradicionales como las reacciones de evolucion de hidrogeno (REH) y oxigeno (REO), asi como una alta resistencia a la corrosion y bajo costo. Particularmente, aleaciones binarias y ternarias han demostrado un incremento importante en la actividad de la REH al compararla con los materiales en su estado puro o masivo. Por esta razon, en la busqueda de nuevas alternativas con una aceptable eficiencia al compararla con los materiales a bajo costo, en este trabajo se obtuvieron materiales Ni-TR (TR = La, Ce) por el metodo de reaccion de estado solido, a partir de: a) acetilacetonatos metalicos y b) polvos metalicos. Estos materiales se sinterizaron durante 3 h a diferentes temperaturas (795 o 920 , 1000 y 1200 grados centigrados) a fin de evaluar su efecto en el desempeno electroquimico de los electrocatalizadores. La caracterizacion estructural y morfologica de materiales se realizo por las tecnicas de DRX y MEB, respectivamente. Asimismo, el desempeno electroquimico de los materiales de electrodo se evaluo en la REH utilizando voltametria ciclica (VC) y curvas potenciodinamicas. Los resultados obtenidos muestran que a bajas temperaturas se obtiene una mezcla de oxidos (NiO, CeO{sub 2} y LaNiO{sub 3}); sin embargo a medida que la temperatura de sinterizado se incrementa, se alcanza la formacion de las aleaciones NiO-CeO{sub 2} y NiO-LaNiO{sub 3}, respectivamente. Al mismo tiempo se observo una clara dependencia de la actividad electrocatalitica con la fuente obtencion de estos materiales (Ni-TR).

  15. Avaliação da composição corporal em adolescentes obesos: o uso de dois diferentes métodos Evaluación de la composición corporal en adolescentes obesos: uso de dos metodos diferentes Body composition evaluation in obese adolescents: the use of two different methods

    Directory of Open Access Journals (Sweden)

    Marco Túlio de Mello

    2005-10-01

    Full Text Available A pletismografia é um método rápido e fácil para determinação da composição corporal que utiliza a relação inversa entre pressão e volume. O objetivo do presente estudo foi o de comparar os valores obtidos com o método pletismografia com os valores observados com o DEXA em uma população de adolescentes obesos. Participaram da amostra 88 adolescentes pós-púberes de ambos os sexos, com idades entre 15 e 19 anos (17,01 ± 1,6 ingressantes de um programa de atividade física multidisciplinar. Os voluntários foram submetidos a uma avaliação da composição corporal em dias distintos dentro da mesma semana, pelo método de pletismografia e outra avaliação pelo método DEXA. Quando os métodos foram comparados, não se observaram diferenças significativas entre eles; além disso, foram observadas correlações significativas entre os parâmetros comuns dos dois métodos (massa magra, massa gorda (kg e massa gorda (%, r = 0,88 p La pletismografía es un método rápido y fácil para la determinación de la composición corporal que utiliza la relación inversa entre la presión y el volumen. El objetivo del presente estudio fué el de comparar los valores obtenidos con el metodo pletismografia con los valores observados con el DEXA en una población de adolescentes obesos. Participaron de la muestra 80 adolescentes post púberes de ambos sexos, con edades entre los 15 y los 19 años (17,01±1,6 iniciantes en un programa de actividad física multidisciplinar. Los voluntarios fueron sometidos a una evaluación de la composición corporal en días distintos dentro de la misma semana, por el método de pletismografia y otra evaluación por el método DEXA. Cuando se compararon los métodos, no fueron observadas diferencias significativas entre ellos, además de ello, fueron observadas correlaciones entre los parámetros comunes a los dos métodos (masa magra, masa grasa (kg y masa gorda (%, r = 0,88 p Plethysmography is an easy and

  16. Diffusion Parameters of BeO by the Pulsed Neutron Method; Calcul des Parametres de Diffusion de BeO par la Methode des Neutrons Pulses; Opredelenie diffuzionnykh parametrov BeO s pomoshch'yu metoda impul'snykh nejtronov; Determinacion de los Parametros de Difusion en el BeO por el Metodo de los Neutrones Pulsados

    Energy Technology Data Exchange (ETDEWEB)

    Joshi, B. V.; Nargundkar, V. R.; Subbarao, K. [Atomic Energy Establishment Trombay, Bombay (India)

    1965-08-15

    la position et la longueur du compteur d'une part, la position de la source d'autre part, il est possible d'eliminer la plupart des harmoniques spatiaux. Il est egalement possible de tenir compte de n'importe quel bruit de fond constant pour le calcul de la constante de decroissance. Il faut eviter les laplaciens tres eleves afin de ne pas avoir d {sup h}armoniques du temps. Tous les harmoniques qui restent sont rendus inoperants par un retard en temps adequat. Les auteurs ont determine la constante de decroissance du mode fondamental de la population de neutrons thermiques pour plusieurs laplaciens. Ils discutent les conditions a remplir pour une determination exacte de la constante du refroidissement par diffusion C. Pour la glucine, ils ont obtenu les constantes suivantes: {lambda}{sub 0} (constante d'absorption) = 156, 02 {+-} 4, 37 s{sup -1}. D (coefficient dediffusion) = (1,3334 {+-} 0,0128) * 10{sup 5} cm{sup 2}/s, C (constante du refroidissement de diffusion) = (-4,8758 {+-} 0,5846) * 10{sup 5} cm{sup 4}/s. Les auteurs ont etudie le role que peut jouer, dans la determination des parametres de diffusion, le fait que la contribution du terme en B{sup 6} est neglige; ils montrent qu'il est considerable. Ce serait la probablement la cause des ecarts entre les valeurs de C obtenues pour un meme ralentisseur par differents chercheurs. (author) [Spanish] Los autores describen el empleo del metodo de los neutrones pulsados para determinar con precision los parametros de difusion en moderadores. Con ayuda de este metodo, han obtenido los parametros de difusion en el BeO. Las rafagas de neutrones se generaron mediante un acelerador en cascada pulsando la fuente ionica y empleando la reaccion Be (d, n). Como detector se utilizo un contador proporcional de BF{sub 3} enriquecido. Los autores demuestran que por seleccion adecuada de la posicion y longitud del contador y de la ubicacion de la fuente, pueden eliminarse la mayoria de los armonicos espaciales. En el calculo de

  17. Non-Destructive Testing Methods Applied to Multi-Finned SAP Tubing for Nuclear-Fuel Elements; Essais Non Destructifs de Gaines a Ailettes, en Poudre d'Aluminium Frittee, pour Elements Combustibles; Nedestruktivnye metody ispytaniya rebristykh trub iz spechennogo alyuminikiog'o poroshka dlya yadernykh toplivnykh ehlementov; Metodos de Ensayo No Destructivo Aplicados a Tubos de SAP con Aletas Multiples Destinados a Elementos Combustibles

    Energy Technology Data Exchange (ETDEWEB)

    Lund, S. A. [Danish Central Welding Institution, Copenhagen (Denmark); Knudsen, P. [Danish Atomic Energy Commission, Research Establishment, Risoe (Denmark)

    1965-09-15

    Energia Atomica de Dinamarca ha emprendido el estudio de un reactor de potencia con refrigerante organico y moderador de agua pesada. Los correspondientes elementos combustibles consisten en haces de 19 barras formadas por pastillas de dioxido de uranio sinterizado, encerradas en tubos de producto de aluminio sinterizado (SAP), de 2 m de longitud, provistos de aletas helicoidales. Para obtener condiciones optimas de transmision de calor y mantener la integridad del elemento combustible durante el funcionamiento del reactor, es necesario contar con tubos de muy alta calidad. Se citan dos ejemplos que ponen de manifiesto las estrechas tolerancias dimensionales adoptadas. Para asegurar una calidad adecuada de los tubos, se establecio un control de calidad muy estricto, basado en gran medida en la aplicacion de metodos no destructivos. Se describen en esta memoria las tecnicas desarrolladas para medir el espesor de pared y los diametros, y para descubrir defectos. La compleja seccion transversal, con 24 aletas, impide aplicar metodos ultrasonicos o de comentes de Foucault para medir el espesor de la pared. Por consiguiente, se desarrollo un calibre registrador de rayos beta, cuyo funcionamiento se basa en la atenuacion sufrida por la radiacion beta proveniente de una fuente de {sup 90}Sr colocada en el interior del tubo. Para el registro continuo del espesor de la pared del tubo con seccion transversal mas simple, de 12 aletas, se utiliza un metodo ultrasonico de resonancia por inmersion. Los diametros interno y externo (entre puntos de aletas) se registran de manera continua mediante calibres neumaticos rapidos. Las fallas se detectan mediante la tecnica de eco de impulsos ultrasonicos, y examinando los tubos con corrientes de Foucault. El metodo ultrasonico permite descubrir facilmente las fisuras transversales, pero hasta ahora ha sido imposible utilizarlo para la deteccion de defectos longitudinales. Por consiguiente, ademas del ensayo ultrasonico, se aplica el examen con

  18. Pulsed and Static Neutron Measurements in Light-Water and Heavy-Water Exponentials; Mesures par les Methodes Pulsee et Statique dans les Ensembles Exponentiels a Eau Legere et a Eau Lourde; Izmerenie impul'snykh i staticheskikh nejtronov v ehksponentsial'nykh ustanovkakh s obychnoj i tyazheloj vodoj; Mediciones por los Metodos Pulsados y Estaticos en Conjuntos Exponenciales de Agua Ligera y Agua Pesada

    Energy Technology Data Exchange (ETDEWEB)

    Parkinson, T. F.; Perez, R. B.; Fry, D. N.; Hartley, R. H.; Smith, S. P.D.; Diaz, N. J. [University of Florida, Gainesville, FL (United States)

    1964-04-15

    etant le laplacien geometrique du systeme equivalent sans reflecteur avec gain reflecteur. Modele C: On imagine un systeme sans reflecteur a deux groupes avec gain reflecteur. En comparant les constantes de decroissance obtenues par calcul et par voie experimentale, on constate que seul le modele A assure une concordance satisfaisante. On peut en tirer les conclusions ci-apres: 1. La presence du reflecteur a una grande influence sur la physique du systeme puise. L'hypothese selon laquelle on admet un gain reflecteur n'est pas toujours valable. 2. La valeur de la constante de decroissance {lambda} depend etroitement de la valeur admise pour la probabilite d'absence de fuite de neutrons rapides. Les experiences indiquent que la methode des neutrons puises permet de determiner k{sub {infinity}} pour des ensembles heterogenes de petites dimensions. Des travaux sont en cours sur des barres d'uranium creuses qui permettent de simuler l'emploi de fluides de refroidissement organiques. (author) [Spanish] Desde hace tiempo se recurre a experimentos exponenciales para determinar el laplaciano material de un medio multiplicador. En fecha mas reciente se ha comenzado a utilizar la tecnica de los neutrones pulsados para medir los valores propios del tiempo, {lambda}, de los que puede deducirse k{sub {infinity}}. Este ultimo metodo presenta la ventaja de que permite el empleo de reticulados mas pequefios que el metodo exponencial estatico. Sin embargo, para establecer la validez del metodo pulsado, es preciso comparar sus resultados con los obtenidos mediante los metodo estaticos. Los autores han efectuado estas mediciones en sistemas con y sin reflector, utilizando H{sub 2}O y D{sub 2}O en calidad de moderador; en los experimentos emplearon un tanque de 1 m de diametro. La correlacion entre las constantes de decrecimiento medidas y los parametros pertinentes del sistema se efectuo empleando un modelo teorico modificado de un solo grupo (denominado modelo A). El valor de {lambda} se

  19. CONSERVACION DE MANZANAS GRANNY SMITH MINIMAMENTE PROCESADAS POR METODOS COMBINADOS

    OpenAIRE

    GALLEGUILLOS CANALES, PAMELA CRISTINA; GALLEGUILLOS CANALES, PAMELA CRISTINA

    2011-01-01

    Se ha demostrado que el consumo de frutas y hortalizas tiene un efecto beneficioso para la salud. Debido a su alto contenido de antioxidantes, constituye una de las maneras más efectivas para reducir el riesgo de enfermedades crónicas no transmisibles (Speisky, 2006; Block et al., 1992; Knekt et al., 1997; Ness y Powles, 1997; Doll, 1990; Wang et al., 1996; Del Caro et al., 2004). El aumento de muertes por enfermedades como cáncer, diabetes y enfermedades cardiovasculares, ha llevado a ent...

  20. Il metodo della fisica e le problematiche della biologia

    Directory of Open Access Journals (Sweden)

    Tripodi, G

    2007-07-01

    Full Text Available Following the ancient Hermetic aphorism solve et coagula, we investigate the nature of the interface between physics and biology by moving up and down the different temporal and spatial scales which enter the description of natural phenomena. Various indications seem to support both the existence of such an interface and the possibility of finding methods, languages, and targets shared by such two disciplines. However, this possibility becomes remote if one moves further and further from the microscopic level of atoms and molecules (and, correspondingly, of molecular biology. We conclude that the biologically founded epistemology proposed by Maturana and Varela as well as cultural anthropology and sociology cannot yet be treated with the methodology of physics.

  1. Il metodo di Aristarco à solo un modello?

    Science.gov (United States)

    Sigismondi, Costantino; Agolini, Giorgia

    2017-06-01

    The method of Aristarchus of Samo to measure the distance Earth-Sun is well known as the first step in the cosmological distance ladder. Our task is to understand if it is worth to repeat it also experimentally, with positive conclusions, especially with respect to the experimental design.

  2. Ensenanza de la Astronomia a Traves de Metodos no Tradicionales

    Science.gov (United States)

    Tignanelli, H. L.

    1990-11-01

    REUMEN: Se presentan los aspects pri nc ipales de a ense? anza de la astronor:. a para -; s. En esta cc .unicaci #n, 5 ha especial mfasis em Ia descripci':"n de las caracteristicas y las posibi lidades peda gicas de los no tradicionales de aprendiZaje. E' : In the following the principal aspects of teaching of astrono ..y for children) are oresented. In this paper, special emphasis has been given to desc rib the characteristics and pedagogical possibilities of the non traditional methods of learning. : TEACHING

  3. El Metodo Llamado Proyecto (The Project Approach). ERIC Digest.

    Science.gov (United States)

    Katz, Lilian G.

    A project is an in-depth investigation of a topic worth learning more about, usually undertaken by a group of children within a class. The goal of a project is to learn more about a topic rather than to find answers to questions posed by a teacher. Project work is complementary to the systematic parts of a curriculum. Whereas systematic…

  4. A {beta} - {gamma} coincidence; Metodo de coincidencias {beta} - {gamma}

    Energy Technology Data Exchange (ETDEWEB)

    Agullo, F

    1960-07-01

    A {beta} - {gamma} coincidence method for absolute counting is given. The fundamental principles are revised and the experimental part is detailed. The results from {sup 1}98 Au irradiated in the JEN 1 Swimming pool reactor are given. The maximal accuracy is 1 per cent. (Author) 11 refs.

  5. Impacto orcamentario da utilizacao do Metodo Canguru no cuidado neonatal

    Directory of Open Access Journals (Sweden)

    Aline Piovezan Entringer

    2013-10-01

    Full Text Available OBJETIVO Estimar o impacto orçamentário da utilização do Método Canguru na rede municipal de saúde. MÉTODOS Um modelo de decisão analítico foi desenvolvido para simular os custos do Método Canguru e Unidade Intermediária Neonatal no Rio de Janeiro, RJ, em 2011. A população de referência foi constituída pelos recém-nascidos estáveis clinicamente, que podem receber assistência nas duas modalidades de cuidado. O impacto orçamentário foi estimado para uma coorte hipotética de 1.000 recém-nascidos elegíveis em um ano. A proporção de recém-nascidos elegíveis que recebem assistência nas duas modalidades foi obtida por coleta de dados nas maternidades incluídas no estudo. As probabilidades dos eventos e o consumo de recursos de saúde, no período da assistência, foram incorporados ao modelo. Cenários foram desenvolvidos para refletir a adoção do método Canguru em maior ou menor escala. RESULTADOS A utilização do Método Canguru significou redução de gastos equivalente a 16% em um ano, se todos os recém-nascidos elegíveis fossem assistidos por esse método. CONCLUSÕES A opção Método Canguru é de menor custo comparado com a da Unidade Intermediária Neonatal. A análise de impacto orçamentário da utilização desse método no Sistema Único de Saúde indicou economia importante para o período de um ano.

  6. Per una teoria generale (disgiunta ma unificata del metodo

    Directory of Open Access Journals (Sweden)

    Mario Gennari

    2015-12-01

    Full Text Available What is a general methodology of science? What is a general theory of method? The article examines the two questions and summarizes the passages that connect – not only in a separate but also in a unified way – recognition, understanding, reasoning and abduction. Then induction, deduction, explanation and interpretation, in order to come finally to the meaning of fact. The general theory of method not divides the natural sciences, but blend them in an unitary project.

  7. Adaptyvaus 2d pozicionavimo metodo autonominiam robotui tyrimas

    OpenAIRE

    Senvaitis, Vytautas

    2016-01-01

    Overview SLAM algorithm, laser distance scanner working principle, EKF and UKF filters in analytical part. EKF mathematical models are implemented for autonomous robot whit two-wheel drive and for laser distance scanner. EKF and UKF filters are compared. 2D robot positioning with EKF filter are modeled and simulated in MATALB and STM32 microcontroller with DSP library. MATLAB and STM32 are compared in speed test. Analyzing EKF filter working. Design and construct autonomous robot experimental...

  8. New Methods and Facilities for the Measurement of Physical Properties of Reactor Components and Irradiated Materials; Nouveaux Procedes et Instruments de Mesure des Proprietes Physiques des Elements de Reacteur et des Matieres Irradiees; Novye metody i sredstva izmereniya fizicheskikh s vojstv komponentov reaktora i obluchennykh materialov; Nuevos Metodos y Equipos para Medir Propiedades Fisicas de Componentes de Reactor y de Materiales Irradiados

    Energy Technology Data Exchange (ETDEWEB)

    Foerster, F.; Mueller, P. [Institut Dr. Foerster, Reutlingen, Federal Republic of Germany (Germany)

    1965-09-15

    zone 'chaude ' du reacteur. Ils discutent la relation entre la conductivite electrique et la dose d'irradiation. Les auteurs decrivent un instrument de mesure de la permeabilite, de la remanence et de la force co- ercitive en fonction des contraintes mecaniques, de la deformation elastique et inelastique et de la dose d'irradiation. Ils donnent des mesures de la variation des proprietes magnetiques en fonction des contraintes elastiques et de la deformation inelastique. Ils etudient les effets de l'irradiation sur la permeabilite et sur la force coercitive. Les auteurs decrivent un instrument permettant la mesure rapide et la lecture directe de la permeabilite des elements en acier inoxydable. Ils expliquent la correlation entre la permeabilite et la teneur en ferrite {Delta}. Us discutent certaines mesures du pourcentage de ferrite {Delta} dans les soudures de tubes en acier inoxydable ainsi que certaines mesures de precipitation de ferrite {Delta} en fonction de la deformation inelastique (forgeage a la main d'elements combustibles pour reacteurs). (author) [Spanish] Se describe un intrumento para medir y registrar en forma totalmente automatica el modulo de Young, el modulodecorte y la capacidad de amortiguamiento, en funcion de la temperatura y el tiempo. El modulo de Young se determina excitando muestras de diversos tamanos con sus frecuencias naturales, mientras que la capacidad de amortiguamiento se mide en funcion de la libre atenuacion de la vibracion, o bien por la anchura media de la curva de resonancia. Se presentan ejemplos de medidas de la recuperacion despues de provocar danos por irradiaciones y deformaciones plasticas asf como grado de grafitacion. Se describe la deteccion de fallas y variaciones de densidad en barras de grafito. Se explica, ademas, un metodo para investigar la retencion de pastillas de UO{sub 2} en tubos austenfticos de pared delgada. Se describe un horno especial para estudiar el comportamiento elastico e inelastico de muestras

  9. Some Possibilities of the Eddy-Current Method for Multi-Parameter Testing of Structural Components; Quelques Possibilites Offertes par la Methode des Courants de Foucault pour le Controle de Nombreux Parametres des Elements de Construction; Nekotorye vozmozhnosti metoda vikhrevykh tokov dlya mnogoparametrovogo kontrolya ehlementov konstruktsij; Algunas Posibilidades que Brinda el Metodo de las Corrientes de Foucault para Controlar Numerosos Parametros de los Elementos de Construccion

    Energy Technology Data Exchange (ETDEWEB)

    Vjahorev, V. G.; Gerasimov, V. G.; Deniskin, V. P.; Trahtenberg, L. I.; Shkarlet, Ju. M. [Gosudarstvennyj Komitet po Ispol' zovaniju Atomnoj Jenergii SSSR, Moskva, SSSR (Russian Federation)

    1965-09-15

    donnees calculees et experimentales, les auteurs indiquent diverses possibilites de realisation de detecteurs a courants de Foucault de frequence unique permettant le controle avec modification simultanee de plusieurs parametres. (author) [Spanish] Los autores demuestran que los problemas del control no destructivo de diversos parametros se plantean en la tecnologia nuclear segun ciertas leyes y que el metodo de las corrientes de Foucault se adapta particularmente a la solucion de varios de esos problemas. Los autores justifican la utilizacion de modelos electricos para resolver problemas de control con ayuda de una larga bobina hueca. Presentan formulas y exponen un metodo para el calculo de detectores a base de corrientes parasitas. Describen un dispositivo que permite verificar el espesor de las paredes de tubos; en este dispositivo, el desplazamiento del tubo a controlar no ejerce influencia alguna sobre los resultados de las mediciones, gracias al empleo de un monitor accionado por una senal dependiente de la fase de tension del detector. En calidad de detector se ha empleado un dispositivo destinado al control de los tubos de un autogenerador despues de haber incluido en su circuito una bobina de ensayo. Partiendo de datos calculados y experimentales, los autores senalan diversas posibilidades de realizacion de detectores a base de corrientes de Foucault de frecuencia unica, que permiten efectuar el control con modificacion simultanea de varios parametros. (author) [Russian] Pokazana zakonomernost' voznikno- venija zadach o nerazrushajushhem mnogoparametrovom kontrole v jadernoj tehnologii i celeso- obraznost' reshenija nekotoryh iz nih metodom vihrevyh tokov. Obosnovano primenenie jelektricheskih modelej dlja reshenija zadach kontrolja s ispol'zovaniem dlinnoj prohodnoj katushki. Privodjatsja raschetnye formuly i izlagaetsja metodika rascheta nakladnyh toko- vihrevyh datchikov. Opisana shema pribora dlja kontrolja tolshhiny stenki trub, v kotorom vlijanie pereme

  10. Experience with a New Colour-Scintillographic Method for Diagnosing Liver Tumours and Inflammatory Liver Disorders; Experience d'une Nouvelle Methode d'Enregistrement Scintigraphique en Couleurs, pour le Diagnostic des Tumeurs Hepatiques et des Affections Inflammatoires du Foie; Opyt ispol'zovaniya novogo metoda tsvetnoj'' stsintigrafii dlya diagnostiki pechenochnykh opukholej i vospalitel'nykh protsessov pecheni; Ensayo de un Nuevo Metodo de Registro Centelleografico Policromo, para el Diagnostico de Tumores Hepaticos y de Inflamaciones del Higado

    Energy Technology Data Exchange (ETDEWEB)

    Sparchez, T.; Gheorghescu, B.; Steclaci, A.; Merculiev, E.; Popovici, M. [Clinique Medicale, Bucarest (Romania)

    1964-10-15

    que le noir represente l'activite maximum, situee au centre du foie ou le parenchyme est plus epais. Les couleurs intermediaires correspondent aux differentes zones d'isoradioactivite. Les auteurs ont etudie, a l'aide de cette methode, 150 cas de tumeurs hepatiques malignes (primitives et secondaires) et de tumeurs benignes, 80 cas d'hepatite chronique et de cirrhose et 50 cas normaux. Dans la majorite descas, ils ont utilise l'or-198 colloiedal (Amersham-Angleterre) injecte par voie intraveineuse. Ils ont effectue parallelement, dans un grand nombre de cas, des mecanogrammes, photoscintigrammes en blanc et noir et scintigrammes en couleurs. Le diagnostic a ete verifie par ponction, laparoscopie, laparophoto ou cinematographie, ponction biopsique, intervention chirurgicale ou necropsie. La methode scintigraphique en couleurs permet de mieux distinguer les variations d'intensite de la radioactivite, c'est-a-dire la desorganisation ou la substitution du parenchyme hepatique par processus tumoraux. (author) [Spanish] Para obtener imagenes que reflejasen mejor los detalles de la estructura del parenquima hepatico modificado por la enfermedad, los autores adaptaron al aparato Scanner-Tracerlab un dispositivo gracias al cual se pueden obtener diagramas hepaticos en siete colores. Cada color, elegido arbitrariamente, corresponde a un numero dado de impulsos y representa zonas de isorradiactividad, es decir, de tejido hepatico de volumen relativamente igual. En el centelleograma policromo, el blanco representa la radiactividad de fondo, mientras que el negro representa la actividad maxima, situada en el centro del higado, donde el parenquima es mas espeso. Los colores intermedios corresponden a las diferentes zonas de isorradiactividad. Recurriendo a este metodo, los autores estudiaron 150 casos de tumores hepaticos malignos (primitivos y secundarios) y de tumores benignos, 80 casos de hepatitis cronica y de cirrosis, y 50 casos normales. En la mayoria de los casos utilizaron

  11. Elements of a thermic method of preparing beta-sources with fused carriers, including strontium-90; Elements d'une methode thermique de preparation de sources beta avec des entraineurs fondus, y compris le strontium-90; Osnovy termicheskogo metoda prigotovleniya beta-istochnikov s plavlennymi nositelyami, vklyuchayushchimi strontsij-90; Bases de un metodo termico de preparacion de fuentes beta con portadores fundidos, incluido el estroncio-90

    Energy Technology Data Exchange (ETDEWEB)

    Bogdanov, N I; Zakharova, K P; Zimakov, P V; Kulichenko, V V

    1962-01-15

    comprises entre 100 et 1000{sup o}C, et expliquent le choix des parametres de base du procede employe. Ils precisent les fondements de la methode qui consiste a monter une preparation vitreuse contenant la quantite necessaire de {sup 90}Sr, sur des supports de forme et dimensions diverses en acier, ceramique et autres matieres. Enfin, les auteurs examinent les parametres de base qui permettent l'exploitation sure et sans danger des differents types de sources, et ils donnent des renseignements sur les sources de {sup 90}Sr preparees par la methode thermique. (author) [Spanish] Las fuentes de radiaciones ionizantes basadas en el radioisotopo {sup 90}Sr se utilizan ampliamente en la industria para los dispositivos y sistemas de control y regulacion automaticos. La preparacion de las fuentes consiste en la deshidratacion de una mezcla formada por una solucion radiactiva de nitrato de estroncio, y compuestos tales como el anhidrido borico, silice, alumina, etc. Por calentamiento de la mezcla deshidratada a temperaturas elevadas, se obtiene una masa fundida muy fluida que, una vez fria, da una masa vitrea que contiene la cantidad requerida de {sup 90}Sr. Los autores presentan datos y examinan los resultados obtenidos al estudiar la deshidratacion del sistema SrO - B{sub 2}O{sub 3}- SiO{sub 2} a temperaturas comprendidas entre 100 y 1000{sup o} C; tambien explican su eleccion de los parametros basicos del proceso tecnologico. Exponen en lineas generales un metodo que consiste en montar sobre acero, materiales ceramicos u otras sustancias, de distintas formas y dimensiones, una masa vitrea que contenga la cantidad requerida de {sup 90}Sr. La memoria estudia los parametros fundamentales para lograr una explotacion regular y segura de los distintos tipos de fuente, y presenta datos relativos y fuentes de {sup 90}Sr preparadas por el metodo termico. (author) [Russian] Istochniki ioniziruyushchikh izluchenij na osnove radioizotopa Sr''9''0 shiroko primenyayutsya v priborakh i skhemakh

  12. A Quick Method of Measuring and Analyzing {beta} Emitters in Solution of Very Low-Level Specific Activity; Remarques sur une technique rapide de mesure et d'analyse d'emetteurs {beta} en solution de tres faible activite specifique; Zamechaniya o bystroj tekhnike izmereniya i analize izluchatelej {beta}-chastits v rastvore s ochen' slaboj spetsificheskoj aktivnost'yu; Observaciones sobre un metodo rapido de medicion y analisis de emisores {beta} en soluciones de muy baja actividad especifica

    Energy Technology Data Exchange (ETDEWEB)

    Le Gallic, Y; Grinberg, B; Thenard, M [Centre d' Etudes Nucleaires de Saclay (France)

    1960-06-15

    vaina de contadores conectados en anticoincidencia con los primeros. 2. Ademas enumeran las posibilidades y campos de utilizacion del metodo que: a) especialmente en el caso de los emisores {beta} blandos, permite medir actividades especificas mucho mas bajas que cuando se utilizan contadores para liquidos; b) permite descubrir las sustancias radiactivas presentes como impurezas en determinados radioelementos (por ejemplo, 2/10 000 de P{sup 32} en S{sup 35}); c) para la mayor parte de los radioelementos permite medir, sin necesidad de proceder a una concentracion previa, actividades especificas de igual orden de magnitud que los limites de tolerancia actualmente admitidos. (author) [Russian] 1. Opisanie mekhanizma izmereniya so slabym fonom prednaznachennog o dlya izmereniya radioaktivnykh produktov v zhidkom sostoyanii, kotoryj sostoit v osnovnom iz dvukh ploskikh schetchikov s odnim oknom i odnogo ploskogo schetchika s dvumya oknami, raspolozhenny kh parallel'no drug k DRUGU i izolirovanny kh vnutri zashchitnoj obolochkoj schetchikov, vstavlen- nykh takim obrazom, chtoby oni ne sovpadali s pervymi. 2. Vozmozhnosti i oblasti ispol'zovaniya metoda: a) ehtot metod pozvolyaet izmerit' gorazdo bolee slabuyu spetsificheskuyu aktivnost', chem ehto vozmozhno s zhidkotnymi schetchikami, v chastnosti s izluchatelyami ne zhestkikh {beta}-chastits; b) ehtot metod pozvolyaet obnaruzhivat' radioaktivnye primesi vnutri radioehlementa (napr. 2/10 OOO R{sup 32} v S{sup 35}); s) ehtot metod pozvolyaet dlya bol'shinstva radioehlemento v izmeryat' bez predvaritel'no j kontsentratsii spetsificheskuyu aktivnost' sootvetstvenno ravnuyu prinyatym v nastoyashchee v nastoyashchee vremya predel'nym dopuskam. (author)

  13. New tools for subsurface imaging of 3D seismic Node data in hydrocarbon exploration =

    Science.gov (United States)

    Benazzouz, Omar

    A aquisicao de dados sismicos de reflexao multicanal 3D/4D usando Ocean Bottom NODES de 4 componentes constitui atualmente um sector de importancia crescente no mercado da aquisicao de dados reflexao sismica marinha na industria petrolifera. Este tipo de dados permite obter imagens de sub-superficie de alta qualidade, com baixos niveis de ruido, banda larga, boa iluminacao azimutal, offsets longos, elevada resolucao e aquisicao de tanto ondas P como S. A aquisicao de dados e altamente repetitiva e portanto ideal para campanhas 4D. No entanto, existem diferencas significativas na geometria de aquisicao e amostragem do campo de ondas relativamente aos metodos convencionais com streamers rebocados a superficie, pelo que e necessario desenvolver de novas ferramentas para o processamento deste tipo de dados. Esta tese investiga tres aspectos do processamento de dados de OBSs/NODES ainda nao totalmente resolvidos de forma satisfatoria: a deriva aleatoria dos relogios internos, o posicionamento de precisao dos OBSs e a implementacao de algoritmos de migracao prestack 3D em profundidade eficientes para obtencao de imagens precisas de subsuperficie. Foram desenvolvidos novos procedimentos para resolver estas situacoes, que foram aplicados a dados sinteticos e a dados reais. Foi desenvolvido um novo metodo para deteccao e correccao de deriva aleatoria dos relogios internos, usando derivadas de ordem elevada. Foi ainda desenvolvido um novo metodo de posicionamento de precisao de OBSs usando multilateracao e foram criadas ferramentas de interpolacao/extrapolacao dos modelos de velocidades 3D de forma a cobrirem a extensao total area de aquisicao. Foram implementados algoritmos robustos de filtragem para preparar o campo de velocidades para o tracado de raios e minimizar os artefactos na migracao Krichhoff pre-stack 3D em profundidade. Os resultados obtidos mostram um melhoramento significativo em todas as situacoes analisadas. Foi desenvolvido o software necessario para o

  14. The Role of Non-Destructive Testing in Test-Reactor Operation at the National Reactor Testing Station; Role des Essais Non Destructifs dans l'Exploitation des Reacteurs d'Essai au Centre National d'Essais de Reacteurs; Rol' nedestruktivnykh ispytanij pri ehkspluatatsii ispytatel'nykh reaktorov na natsional'noj stantsii po ispytaniyam reaktorov; Papel de los Metodos No Destructivos en la Explotacion de los Reactores de la National Reactor Testing Station

    Energy Technology Data Exchange (ETDEWEB)

    Francis, W. C.; Brown, E. S.; Burdick, E. E.; Gibson, G. W.; Tingey, F. H. [Phillips Petroleum Company, Atomic Energy Division, Idaho Falls, Idaho (United States)

    1965-10-15

    'un densimetre, permettent de determiner la distribution du combustible. On a habituellement recours a la radiographie des soudures pour les parties constitutives des reacteurs et des boucles d'essai. Le dispositif perfectionne de mesure de la reactivite (Advanced Reactivity Measurement Facility, ARMF) permet de determiner, pour chaque cycle de reacteur, l'irradiation du combustible et l'empoisonnement dans des specimens. Une application assez peu courante pour un assemblage critique est la mesure de la teneur en bore du combustible dans l'assemblage critique d'essai en genie des reacteurs (Engineering Test Reactor Critical Facility, ETRC). Le controle par courants de Foucault et par des procedes mecaniques de l'espacement des plaques de combustible et la mesure par courants de Foucault de l'epaisseur de l'oxydation (corrosion) sur les plaques irradiees ont donne d'excellents resultats. Des methodes complementaires qui ont fait leurs preuves sont l'inspection par liquide penetrant et les essais a l'azote liquide pour les craquelures superficielles, les essais par recuit thermique pour les souitlures et l'exploration par rayons gamma des plaques irradiees. On a recours a l'essai hydraulique d'un echantillon statistique d'elements combustibles pour verifier l'integrite structurale, notamment la resistance de la liaison entre les plaques de combustible et la gaine. Des efforts constants sont deployes pour ameliorer les methodes actuelles et mettre au point de nouveaux procedes de controle non destructif. (author) [Spanish] Los reactores de ensayo de la National Reactor Testing Station suponen una enorme inversion (superior a 100 millones de dolares) y la necesidad de explotarlos en condiciones de seguridad obliga a proceder a un control de calidad muy estricto de los componentes nucleares y de ensayo, especialmente en lo que respecta a los elementos combustibles y de control. Por tanto, los metodos no. destructivos son fundamentales para determinar la calidad de estos componentes

  15. Multichannel time-analyser with an electrostatic memory tube; Analyseur en temps a plusieurs canaux, avec memoire a potentioscopes; Mnogokanal'nye vremennye analizatory s pamyat'yu na potentsialoskopakh; Analizador multicanal de tiempo con tubo de memoria electrostatico

    Energy Technology Data Exchange (ETDEWEB)

    Ignat' ev, K G; Kirpichnikov, I V; Sukhoruchkin, S I

    1962-04-15

    The Academy of Sciences of the USSR has built two multichannel time-analysers with an LN-4 electrostatic memory tube for pulse analysis. These analysers are at present being used for various kinds of measurements; they have the following characteristics: Number of channels - 1024 and 2048, Channel time width - from 0.2 {mu}s upwards, Channel capacity - 4096 pulses and 1024 pulses, Analyser trigger frequency - up to 1000 per second, Pulse load - up to 1000 pulses per second. Measurement results are given by the analysers in the form of graphs and numerical data on perforated cards. (author) [French] A l'Institut de physique theorique et experimentale de l'Academie des sciences de l'Union sovietique, on a construit deux analyseurs d'impulsions en temps, a plusieurs canaux, avec memoire a potentioscopes du type LN-4. A l'heure actuelle ils sont employes pour diverses mesures; leurs caracteristiques sont les suivantes: Nombre de canaux - 1024 et 2048 respectivement, Largeur des canaux en temps-egale ou superieure a 0,2 {mu}s Capacite des canaux - 4096 et 1024 impulsions Frequence de declenchement maximum des analyseurs - 1000 fois par seconde Charge maximum - 1000 impulsions par seconde. Les resultats des mesures sont communiques par les analyseurs sous forme de graphiques et de donnees numeriques sur cartes perforees. (author) [Spanish] En el Instituto de Fisica Teorica y Experimental de la Academia de Ciencias de la Union Sovietica se han construido dos analizadores multicanales de tiempo con un tubo de memoria electrostatico LN-4 para el analisis de impulsos. Estos analizadores, que se utilizan actualmente para efectuar diversos tipos de mediciones, tienen las siguientes caracteristicas: Numero de canales: 1024 y 2048, Anchura de los canales: a partir de 0,2 {mu}s, Capacidad de los canales: 4096 y 1024 impulsos, Frecuencia de disparo del analizador: hasta 1000 por segundo, Carga: hasta 1000 impulsos/s. Los analizadores expresan los resultados de las mediciones en forma de graficos y de datos numericos en fichas perforadas. (author) [Russian] V ITEHF AN SSSR byli so z d a ny dva mnogokanal'nykh vremennykh analizatora impul'sov s ''pamyat'yu'' na potentsialoskopakh JIH-4. V nastoyashchee vremya oni ISPOL'ZUYUTSYA V razlichnykh izmereniyakh i imeyut sleduyushchie kharakteristiki: chislo kanalov - 1024 i 2048; vremennaya shirina kanalov ot 0,2 mksek. i bol'she; emkost' kanalov - 4096 imp i 1024 imp; chastota zapuska analizatoroa do 1000 raz v sek; velichina zagruzki do 1000 imp/sek. Rezul'taty izmerenij vydayutsya analizatorami v vide grafikov i chislovykh dannykh na perfokartakh. (author)

  16. Development of multichannel system for nuclear radiation spectrometry based on an embedded control and acquisition device Myrio-1900; Desarrollo de sistema multicanal para espectrometria de radiacion nuclear basado en un dispositivo embebido de control y adquisicion MyRIO-1900

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez D, S.

    2016-07-01

    This work describes the design a multichannel analyzer system 4096 channels (Mca) for gamma radiation spectrometry. The multichannel analyzer has as its main component an embedded company National Instruments model NI (Myrio-1900) module, which is integrated by a step of converting analog to digital signals (A / D) and digital-to-analog (D / A) a programmable gate array, and a processor real time (Rt). Through this module the pulses generated by the detector to be processed and subsequently forming the multichannel analyzer are acquired. In addition, a graphical user interface designed to make more use friendly system from a personal computer (Pc), embedded programming module and the user interface was done with the LabVIEW programming environment. tests with different sources of radiation ({sup 60}Co, {sup 226}Ra, {sup 137}Cs) and semiconductor detectors (Ge) and scintillation (Na) were made. Getting results satisfactory. (Author)

  17. Application of the gyroscopic method in subterranean orientation. Comparison with conventional methods. Aplicacion del metodo gyroscopic en la orientacion subterranea. Comparacion con los metodos convencionales

    Energy Technology Data Exchange (ETDEWEB)

    Saez Garcia, E.; Fuente Martin, P.L. (HUNOSA, Madrid (Spain))

    1988-01-01

    This entry tries to revise the most used method for the direction transition what with exterior and interior using plumbs in connected with vertical shaft coalmines. A technical and economic cooperation was also realized between the indicated method and the gyroscope.

  18. COMPARACIÓN DEL ESTADIO FETAL OBTENIDO POSTMORTEM MEDIANTE DOS METODOS ANTROPOMETRICOS. Comparación del estadio fetal obtenido postmortem mediante dos metodos antropometricos

    Directory of Open Access Journals (Sweden)

    Mirta M Aliendo

    2016-03-01

    Full Text Available En la etapa fetal se observa un rápido incremento de la masa corporal y de todas las dimensiones. La literatura evidencia discrepancias sobre los criterios para determinar el estadio fetal post-mortem, en relación a los parámetros morfométricos utilizados, por lo que nuestro objetivo fue comparar la medición morfológica directa (vertex-coxis, tabla de Hansmann con la ultrasonografía (medición del fémur, para establecer el grado de confiabilidad en la determinación post-mortem del estadío fetal. Se utilizaron 120 fetos: 1 grupo A (60 fetos estadificado ecográficamente y 2 grupo B (60 fetos estadificado por tabla de Hansmann. A ambos grupos se le realizaron múltiples mediciones siguiendo parámetros probados según la literatura internacional. Se utilizó calibre de precisión. Parámetros evaluados: longitud vertex-coxis, circunferencia cefálica, diámetro cefálico occipito-frontal, biparietal, longitud mentón-vertex, perímetro toráxico-transverso, circunferencia abdomi-nal y longitudes de brazo, antebrazo, mano, muslo, pierna y pie. Estos valores fueron agrupados por semanas, obteniéndose la media y aplicándose la prueba t de Student. Los resultados demostraron que la diferencia entre los parámetros medidos en el grupo A y en el grupo B eran significativas en todas las semanas, por lo que se observa disparidad en la determinación del estadio fetal por ecografía y los registros correspondientes a la medición vertex-coxis (tabla de Hansmann postmortem. Concluímos que los resultados obtenidos por ambas modalidades de medición son diferentes para una misma edad gestacional y, por ende, resultaría más apropiado referirse a fetos con ciertas dimensiones según alguno de estos parámetros que a “edad gestacional”.In fetal stage, body mass and measurements quickly increase. Scientific literature shows differences on the criteria to determine the post-mortem fetal stage, depending on morphometric parameters. Our objective was to compare both methods, direct morphologic measures (crown-rump length, Hansmann table and ultrasonography (femur measurement, to establish their reliability on post-mortem determination of fetal age. One hundred and twenty fetuses were studied: 1 group A (60 fetuses sonographically staged and 2 group B (60 fetuses staged according to Hansmann table. Many measurements were performed on both groups, following internationally determined parameters. We used a precision gauge. Considered parameters were: crown-rump length, head circumference, occipito-frontal diameter, bi-parietal length, chin-vertex length, thoracic transverse perimeter, abdominal circumference, arm, forearm, hand, thigh, leg and foot lengths. Obtained information was grouped by weeks. We calculated the data mean and significant difference was managed by Student t-test. Results demonstrated significant difference in the considered parameters between group A and B, and then, to determine the fetal age.We conclude that results obtained by both measuring modalities were different for the same gestational age, and therefore, it should be more appropriate to consider fetuses by measures obtained following certain parameters than by “gestational age”.

  19. Gastroesophageal reflux diagnosis by scintigraphic method - a comparison among different methods; Diagnostico de refluxo gastro-esofagico por metodo cintilografico - correlacao com outros metodos

    Energy Technology Data Exchange (ETDEWEB)

    Cruz, Maria das Gracas de Almedia; Penas, Maria Exposito; Maliska, Carmelindo; Fonseca, Lea Miriam B. da; Lemme, Eponina M.; Campos, Deisy Guacyaba S.; Rebelo, Ana Maria de O.; Martinho, Maria Jose R.; Dias, Vera Maria [Hospital Universitario Clementino Fraga Filho, Rio de Janeiro, RJ (Brazil). Servico de Medicina Nuclear

    1996-07-01

    The gastroesophageal reflux disease is characterized by the return of gastric liquid to the esophagus which can origin the reflux esophagitis. The aim is to evaluate the contribution of dynamic quality scintigraphy of reflux (CTR) in the diagnosis of DRGE. We studied a ground of sick people with typical symptoms and compared the results given by digestive endoscopy (EDA), the histopathology and 24 hours pHmetry. There have been evaluated 24 healthy individuals and 97 who were sick. The first ones were submitted to CTR. In 20 controlled and 34 patients, the reflux index (IR) was determined by the evaluation of the reflux material percentage in relation to the basal activity. All the sick patients were submitted to CTR and EDA. This one classified them in: group A with esophagitis 45 patients (46,4%) where 14 did the biopsy of the third segment/part from the esophagus and 16 did the long pHmetry and group B without esophagitis = 52 patients (53.6%), 26 did the biopsy and 36 the pHmetry. In group A the CTR was positive in 38 (84%), the biopsy showed esophagitis in 11 (78,6%) and the pHmetry showed normal reflux in 14 (87,5%). The positivity of the same exams in group B were of 42 (81%), 11 (42,3%) and 19 (53%) respectively. The IR were determined to the controls and the measure to the patients were of 59% and 106% respectively as p<0,0001 (test from Mann Whitney). The correlation of CTR with the other methods showed sensitivity of 84,1%, specificity of 95,8%, positive predictive value of 98,3% and negative predictive value of 67,7%. As it was showed the authors concluded that the scintigraphy method can confirm the diagnosis of DRGE in patients of typical symptomology which canbe recommended by the initial of investigation method in these conditions. (author)

  20. Recent Methods in Crystal Spectrometry; Methodes Recentes de Spectrometrie a Cristal; 041d 041e 0412 042b 0415 041c 0415 0422 041e 0414 042b 041a 0420 0418 0421 0422 0410 041b 041b 0418 0427 0415 0421 041a 041e 0419 0421 041f 0415 041a 0422 0420 041e 041c 0415 0422 0420 0418 0418 ; Metodos Recientes de Espectrometria Cristalina

    Energy Technology Data Exchange (ETDEWEB)

    Iyengar, P. K. [Atomic Energy Establishment Trombay, Bombay (India)

    1965-06-15

    combinado con un detector, que permite ganar intensidad en las mediciones por dispersion inelastica. Una dificultad que suscita su empleo con muestras de dispersion coherente es la indeterminacion de la transferencia de impulso. Recientemente se han utilizado en trabajos de dispersion inelastica dos filtros combinados, con cortes diferentes, y un contador para detectar los neutrones retrodispersos por el segundo filtro, que forma una ventana. Esto permite mejorar la resolucion energetica y la definicion de la transferencia de impulso. Se presentan algunas mediciones relativas a las caracteristicas de este tipo de filtro. Aprovechando la definicion en vector de onda de los neutrones detectados, el filtro de ventana se ha utilizado con exito para determinar las curvas de dispersion de fonones en redes cristalinas. Como este instrumento biaxial sirve para los mismos fines que el triaxial, supone una simplificacion constructiva. Se ha aplicado con tal dispositivo el metodo de Q constante. Se presentan resultados de mediciones tipicas. El principal inconveniente de la espectrometria mediante cristales es que solo se utiliza un angulo de dispersion cada vez. Puede superarse empleando un espectrometro de varios brazos. Se describen las caracteristicas y empleo de un espectrometro de este tipo para medir la distribucion de la energia. La posibilidad de hacer funcionar todos los brazos del espectrometro segun el modo de Q constante supone una ventaja adicional para el estudio de muestras monocristalinas. Este procedimiento permitiria en el futuro aumentar considerablemente la velocidad de acopio de datos cuando se emplee la tecnica del espectrometro de cristal. (author) [Russian] Princip difrakcii na kristalle otkryvaet put' dlja prostogo raspredelenija jenergii medlennyh nejtronov. Odnako na kolichestvennoe opredelenie raspredelenija jenergij vljjajut razlichnye parametry, zavisjashhie ot struktury jelementarnoj jachejki kristallicheskogo monohromatora i geometricheskogo

  1. Current Practice in the Management of High-Bevel Radioactive Wastes in the United States of America; La Pratique Courante de Gestion des Dechets de Haute Activite aux Etats-Unis d'Amerique; 0421 041e 0412 0420 0415 041c 0415 041d 041d 042b 0414 0 ; Metodos Corrientes de Tratamiento y Evacuacion de Desechos de Elevada Actividad Aplicados en los Estados Unidos de America

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, Bruce F.; Doud, Edward; Tomlinson, R. E. [General Electric Company, Hanford Atomic Products Operation, Richland, WA (United States)

    1963-02-15

    diversos tipos de deposito representan en cada caso una solucion equilibrada cuyos factores determinantes son la seguridad de funcionamiento, la duracion y el costo. Los gastos de inversion unitarios correspondientes a los dispositivos de almacenamiento de desechos actualmente utilizados oscilan entre 0,47 y 2, 66 dolares/gal. Tambien han de incluirse en el calculo de los gastos a largo plazo los correspondientes a vigilancia, tratamiento o transvase de desechos e instalaciones de reemplazo. Los autores llegan a la conclusion de que los datos disponibles no permiten por ahora formular predicciones precisas. En Hanford se utilizan depositos de hormigon armado, con revestimiento de acero al carbono, para almacenar soluciones radiactivas. En cuatro de los 145 depositos puestos en servicio desde 1945, se produjeron escapes despues de contener durante periodos de 8 a 12 anos desechos que no generan calor. En cada caso, el contenido de los depositos se transvaso por medio de bombas a otro recipiente. Si bien se detecto radiactividad en el terreno circundante de los depositos defectuosos, la radiactividad no paso a las aguas subterraneas. Otro deposito fue retirado del servicio al observarse una deformacion de su revestimiento de acero al carbono. En Savannah River, se construyen recipientes de acero al carbono alojados en bovedas de hormigon. En cuatro de estos depositos, de un total de 14, se han formado pequenas grietas en las paredes laterales a consecuencia de corrosion con tension en las zonas afectadas por la soldadura. La pequena cantidad de desechos que escapo por las grietas se recogio en la boveda y se volvio a introducir en los depositos. En la actualidad ha cesado el escape y los recipientes siguen utilizandose. En Idaho Falls, se estan construyendo depositos de acero inoxidable alojados en boveda de hormigon. No se han planteado problemas ni se han observado defectos en los depositos. Si bien los metodos actuales de almacenamiento de soluciones radiactivas son

  2. Dose estimation by biological methods; Estimacion de dosis por metodos biologicos

    Energy Technology Data Exchange (ETDEWEB)

    Guerrero C, C; David C, L; Serment G, J; Brena V, M [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1997-07-01

    The human being is exposed to strong artificial radiation sources, mainly of two forms: the first is referred to the occupationally exposed personnel (POE) and the second, to the persons that require radiological treatment. A third form less common is by accidents. In all these conditions it is very important to estimate the absorbed dose. The classical biological dosimetry is based in the dicentric analysis. The present work is part of researches to the process to validate the In situ Fluorescent hybridation (FISH) technique which allows to analyse the aberrations on the chromosomes. (Author)

  3. La Società Umanitaria e la diffusione del Metodo Montessori (1908-1923

    Directory of Open Access Journals (Sweden)

    Irene Pozzi

    2015-07-01

    Full Text Available The Società Umanitaria ofMilan, between 1918 and 1923, played an essential role in spreading and developing the Montessori Method. Studying in the Historical Archive of Società Umanitaria the numerous documents there collected, the author reconstructed the crucial moments of the extremely significant collaboration between Maria Montessori and Augusto Osimo, General Secretary of the Società Umanitaria.This complex and in-depth investigation was guided by the analysis, in specific, of the training courses for Montessori teachers organised by Società Umanitaria, essentially unexamined before this study, that allowed the researcher to have a deep insight into the action of Società Umanitaria aimed to promote and implement the Montessori Method in Italy and all around the world.

  4. ESTUDIO CONFORMACIONAL EN ALGUNAS 1,3-OXAZINAS Y 1,3-BENZOXAZINAS EMPLEANDO METODOS TEORICOS.

    OpenAIRE

    HURTADO OCAMPO, SANDRA MARCELA; HURTADO OCAMPO, SANDRA MARCELA

    2007-01-01

    En la década del cincuenta, resultados experimentales entregados por Urbanski y colaboradores [1] pusieron en evidencia propiedades antituberculósicas y antitumorales en compuestos del tipo 5-nitro-R-N-1 ,3- oxazínicos. Como resultado de un proceso relati 187p.

  5. Synovial chondromatosis of the shoulder: imaging findings; Osteocondromatose sinovial no ombro: achados por metodos de imagem

    Energy Technology Data Exchange (ETDEWEB)

    Terazaki, Carlos Renato Ticianelli; Trippia, Carlos Henrique; Caboclo, Maria Fernanda Sales Ferreira; Medaglia, Carla Regina Miranda, E-mail: reticianelli@hotmail.com [Hospital Sao Vicente (FUNEF), Curitiba, PR (Brazil). Servico de Radiologia e Diagnostico por Imagem; Trippia, Cesar Rodrigo [Hospital Sao Vicente (FUNEF), Curitiba, PR (Brazil)

    2014-01-15

    Synovial chondromatosis is a benign condition characterized by synovial proliferation and metaplasia, with development of cartilaginous or osteocartilaginous nodules within a joint, bursa or tendon sheath. In the shoulder, synovial osteochondromatosis may occur within the glenohumeral joint and its recesses (including the tendon sheath of the biceps long head), and in the subacromial-deltoid bursa. Such condition can be identified either by radiography, ultrasonography or magnetic resonance imaging, showing typical features according to each method. Radiography commonly shows ring-shaped calcified cartilages and periarticular soft tissues swelling with erosion of joint margins. Ultrasonography demonstrates hypoechogenic cartilaginous nodules with progressive increase in echogenicity as they become calcified, with development of posterior acoustic shadow in case of ossification. Besides identifying cartilaginous nodules, magnetic resonance imaging can also demonstrate the degree of synovial proliferation. The present study is aimed at describing the imaging findings of this entity in the shoulder. (author)

  6. Microbicidas Metodo de Prevencion en VIH/SIDA Controlado por Mujeres.

    Science.gov (United States)

    Ruiz, Cindy; Torres, Viviana; Cianelli, Rosina; Ferrer, Lilian

    2009-03-01

    HIV/AIDS continues to expand throughout the world, and in recent times has had a severe impact on the number of women living with HIV. Access to methods of prevention for HIV/AIDS around the world is limited and for many women may not be feasible. Examples of such methods are sexual abstinence, which though recognized as an effective method of prevention is difficult for many women to achieve. Mutual fidelity is another option, but many women cannot control the sexual behavior of their partners. Finally, the male condom continues to be an available method of HIV prevention for sexually active people. However, in many places, gender inequality, social norms, and economic disparities severely limit women's capacity to negotiate the use of a condom with their partner. For this reason, an urgent need exists to develop a product for the prevention of HIV/AIDS that can be handled by women. Microbicides, products that can reduce HIV risk when applied intravaginally, hold promise for stopping the advance of HIV/AIDS, especially when considering that women can make their own decisions about whether to use them when other methods of prevention are not available. The objective of the current literature review was to understand the scientific advances related to microbicides in the prevention of HIV/AIDS in women through the analysis of available literature in this area. Interest in this topic emerged from the need to contribute to women's health and HIV/AIDS prevention. To achieve this review's objective, a search was carried out in multiple databases, including OVID, PUBMED, PROQUEST, and CINAHL, as well as published materials from organizations related to this area such as UNAIDS and CONASIDA, and literature available from the Internet. Upon completion of the literature review, it was concluded that microbicides are an effective method for preventing HIV/AIDS for women as well as their partners. Although they have a high level of acceptance among the female population, the majority of microbicides are still in clinical studies, requiring further evaluation for their safe use in humans. There are 3 microbicides in the final phases of clinical studies that will soon be available on the market. One of these was found to be 60% effective in protecting against the transmission of HIV and was used by women in 50% of their sexual activity, which resulted in avoiding approximately 2.5 million new HIV infections in men, women, and children over a 3-year period.

  7. ARTE E FENOMENOLOGIA BRANCUSIANA: “IL METODO PURAMENTE SCULTORIO DI PENSARE IL MONDO”

    Directory of Open Access Journals (Sweden)

    MANUELA TEODORA BALAŞCA-MIHOCI

    2010-11-01

    Full Text Available The entailing creative labour reveals works that imply the whole human thinking and sensitivity aiming to comprehend them. Thus, we can reach the great Brancusian art in understanding that, beyond the glance and the material, we find the spiritual; the last is not something untouchable, but it is a sort of co-partner of the creative life experience. Fear, love, pain, happiness, and ecstazy, all the human affinities and the substance of beingness are created by art and by philosophy alike. Merely their expression is different as concerning the material and the word. We find sameness between the capacity of communication using and feeling life through wood or rock, for example, on one hand; and the gift of putting in act and writing words, of interpreting verse, on the other. Such a similarity belongs to the unique creative agent, finally, that is varying only by the material and the expressive shape.

  8. Problemi e di Fisica e Astronomia ed il metodo di Gerberto docente

    Science.gov (United States)

    Sigismondi, Costantino

    2015-04-01

    Teaching Physics and Astronomy to pupils of 14-19 years old requires nowadays a continuous upgrade of knowledge as well as a capacity of selecting topics. The art of presenting arguments made Gerbert the teacher Rogatus a Pluribus in the end of X century and it is still actual; the proposed series of problems wants to link everyday experiences with the mathematical models of the phenomena, to allow the prediction and explanation of the experimental data. These problems of Physics and Astronomy are “observation oriented”, as the method of Gerbert was to start from the experience to get the theory, and not viceversa. Physics is much more than an “applied Algebra”. In the dispute of Ravenna (980) between Gerbert and Otric from Magdeburg, the primacy of Physics with respect to Mathematics was discussed. In the Italian secondary technical schools there are laboratory activities, while there is nothing similar for Lyceums and for the Astronomy teaching which is limited to a series of notions to be learned without any kind of observation; considered too difficult in polluted skyes.

  9. METODO OPTICO PARA MEDIR EL COMPORTAMIENTO DE UNA LINEA DE TRANSMISION.

    OpenAIRE

    ASAHI KODAMA, TAKESHI EDUARDO; ASAHI KODAMA, TAKESHI EDUARDO

    1998-01-01

    El objetivo de esta tesis es el de establecer un método de manera de poder medir en forma óptica la corriente y el voltaje que circulan en una línea de transmisión. Para ello, se utilizan los fenómenos de Faraday y Kerr en líneas de transmisión que tienen 57p.

  10. General method of quantitative spectrographic analysis; Estudio de un metodo general de analisis espectrografico cuantitativo

    Energy Technology Data Exchange (ETDEWEB)

    Capdevila, C; Roca, M

    1966-07-01

    A spectrographic method was developed to determine 23 elements in a wide range of concentrations; the method can be applied to metallic or refractory samples. Previous melting with lithium tetraborate and germanium oxide is done in order to avoid the influence of matrix composition and crystalline structure. Germanium oxide is also employed as internal standard. The resulting beads ar mixed with graphite powder (1:1) and excited in a 10 amperes direct current arc. (Author) 12 refs.

  11. Peripezie di immagini: il metodo-Warburg e la Divina Commedia

    Directory of Open Access Journals (Sweden)

    Gioachino Chiarini

    2012-05-01

    Full Text Available The paper is part of a ‘work in progress’ on the influence of oriental cultures and religions on Western ancient literature (The Seven Gates. After a short history of use and symbolic role of the “planetary ladder” from Sumerians to Islamic literatures and cultures via Greece, Rome and Jewish mysticism, the essai tries to show that the early Christians writers preferred to avoid employing the planetary ladder as a cipher of an itinerary to God. It was only Dante, in his Divina Commedia, who resumed to use with high perfection the planetary ladder: he re-elaboreted the circular Islamic hell in the Inferno, the Islamic heaven in the Paradiso and the Islamic paradise in the Purgatorio (his source was the Latin translation of The book of the ladder of Mahomet.

  12. Obsidian dating by fission track method; Datacao de obsidianas com o metodo dos tracos de fissao

    Energy Technology Data Exchange (ETDEWEB)

    Araya, A M.O.

    1990-12-01

    The fission track method was employed to obtain the age of twelve obsidian sample from Ecuador. By using the plateau-age correction method, we obtained the true age of each sample and were able to identify four groups of ages in the studied area. Thereafter we studied the fading of fission tracks in two obsidian samples with different origins: Yanaurcu, Ecuador and Monte Arci, Italy. We constructed Arrhenius plots and calculated activation energies for both samples. The results from thermal annealing experiments were compared with theoretical curves obtained by integrating an equation proposed by Shukolyukov et al (1965). (author). 43 refs, 20 figs, 10 tabs.

  13. Correlacion entre metodos de analisis de Zn disponible en cuatro ordenes de suelos de Costa Rica

    OpenAIRE

    Eloy Molina; Elemer Bornemisza

    2001-01-01

    Se realizo una comparación entre métodos analisis del Zn disponible en 4 ordenes de sue- Analytilos de Costa Rica (Ultisoles, Vertisoles, Andisoles Inceptisoles, 25 de c/u), utilizando las siguientes soluciones extractoras: Olsen Modificado, Meh- lich 3, Morgan Modificado, DTPA y HC1. Las cantidades de Zn extrafdas dependieron de la natu- raleza qufmica de la solucion extractora. El HCl presento los contenidos mas altos de Zn en los chasuelos, excepto en Vertisoles....

  14. Acrilamida em alimentos : ocorrencia, metodos analiticos e estimativas de ingestão.

    OpenAIRE

    Adriana Pavesi Arisseto

    2007-01-01

    Resumo: Uma importante descoberta de pesquisadores suecos em abril de 2002 mostrou que acrilamida, uma substância provavelmente carcinogênica a seres humanos, pode ser formada em determinados alimentos que são submetidos a tratamento térmico em altas temperaturas. No presente estudo, 111 amostras de diferentes categorias de alimentos foram coletadas em supermercados, lojas de "fast-foods" e restaurantes da cidade de Campinas-SP, entre os meses de setembro de 2004 e abril de 2006, e analisadas...

  15. Alternate method for to realize image fusion; Metodo alterno para realizar fusion de imagenes

    Energy Technology Data Exchange (ETDEWEB)

    Vargas, L; Hernandez, F; Fernandez, R [Departamento de Medicina Nuclear, Imagenologia Diagnostica. Centro Medico de Xalapa, Veracruz (Mexico)

    2005-07-01

    At the present time the image departments have the necessity of carrying out image fusion obtained of diverse apparatuses. Conventionally its fuse resonance or tomography images by X-rays with functional images as the gammagrams and PET images. The fusion technology is for sale with the modern image equipment and not all the cabinets of nuclear medicine have access to it. By this reason we analyze, study and we find a solution so that all the cabinets of nuclear medicine can benefit of the image fusion. The first indispensable requirement is to have a personal computer with capacity to put up image digitizer cards. It is also possible, if one has a gamma camera that can export images in JPG, GIF, TIFF or BMP formats, to do without of the digitizer card and to record the images in a disk to be able to use them in the personal computer. It is required of one of the following commercially available graph design programs: Corel Draw, Photo Shop, FreeHand, Illustrator or Macromedia Flash that are those that we evaluate and that its allow to make the images fusion. Anyone of them works well and a short training is required to be able to manage them. It is necessary a photographic digital camera with a resolution of at least 3.0 mega pixel. The procedure consists on taking photographic images of the radiological studies that the patient already has, selecting those demonstrative images of the pathology in study and that its can also be concordant with the images that we have created in the gammagraphic studies, whether for planar or tomographic. We transfer the images to the personal computer and we read them with the graph design program. To continuation also reads the gammagraphic images. We use those digital tools to make transparent the images, to clip them, to adjust the sizes and to create the fused images. The process is manual and it is requires of ability and experience to choose the images, the cuts, those sizes and the transparency grade. (Author)

  16. Methods in nuclear reactors calculations; Metodos de calculo en reactores nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Velarde, G

    1966-07-01

    Studies are made of the neutron transport equation corresponding to the the real and virtual reactors, as well as the starting hypotheses. Methods are developed to solve the transport equation in slab geometry, and P{sub l}; B{sub l}; M{sub l}; S{sub n} and discrete ordinates approximations. (Author)

  17. Metodo para montaje permanente de huevos de helmintos enteroparasitos Definitive preservation of helminthic eggs

    Directory of Open Access Journals (Sweden)

    Victor Muñoz

    1990-04-01

    Full Text Available Se comunican resultados obtenidos empleando Medio de Hoyer para el montaje de huevos de helmintos enteroparásitos, destinado a preparaciones para colecciones docentes y/o de investigación. La utilización de esta técnica en muestras fecales conteniendo huevos de A. lumbricoides, T. trichiura, Uncinaria sp., Taenia sp., Diphyllobothrium sp., H. nana, H. diminuta y F. hepática, permitió la correcta observación de ellos en lecturas iniciadas a las 24 horas y mantenidas hasta 180 días después.The results using the Hoyer method for examining eggs of helminths enteroparasites are presented. This method is particularly swited for teaching and on research purposes. Using this technique in fecal sample containing eggs of A.lumbricoides, T. trichiura, Uncinaria sp., Taenia sp., Diphyllobothrium sp., H. nana, H. diminuta and F. hepática allowed the correct identification of then after 24 hours up to 180 days after the samples were obtained.

  18. La pronunciacion espanola y los metodos de investigacion. (Spanish Pronunciation and Methods of Investigation.)

    Science.gov (United States)

    Torreblanca, Maximo

    1988-01-01

    Discusses the validity of studies of Spanish pronunciation in terms of research methods employed. Topics include data collection in the laboratory vs. in a natural setting; recorded vs. non-recorded data; quality of the recording; aural analysis vs. spectrographic analysis; and transcriber reliability. Suggestions for improving data collection are…

  19. Persistent hyperplastic primary vitreous: imaging evaluation; Persistencia hiperplastica do vitreo primitivo: avaliacao por metodos de imagem

    Energy Technology Data Exchange (ETDEWEB)

    Jacob, Beatriz Mahmud; Teixeira, Kim-Ir-Sen Santos; Figueiredo, Sizenildo da Silva; Nobrega, Bruno Barcelos da [Universidade Federal de Goias, Goiania (Brazil). Hospital das Clinicas. Dept. de Diagnostico por Imagem]. E-mail: biamjacob@hotmail.com

    2003-06-01

    Persistent hyperplastic primary vitreous (PHPV) is a congenital developmental anomaly of the eye that primarily affects premature infants. PHPV results from failure of regression of the embryogenic primary vitreous and hyaloid vasculature, and proliferation of connective tissue. Three types of PHPV may be found: anterior, posterior and a combination of anterior and posterior. The clinical findings include leukocoria (white pupillary reflex) and microphthalmic eye. This anomaly is usually unilateral and unassociated with other systemic findings. The differential diagnosis between PHPV and other ocular diseases may be difficult due to similar features such as leukocoria, detached retina, retinal folds and cataract. Other diseases with similar features include retinoblastoma, isolated congenital cataract, retinopathy of prematurity and pseudo gliomas or leukocorias. Direct visualization of the remnants of the fetal hyaloid vascular system offers the best evidence of PHPV. However, diagnosis using the ophthalmoscope is sometimes impossible because of opaque tissues. In this circumstance an indirect visualization by ultrasound, computed tomography or magnetic resonance imaging may be useful. These imaging methods provide valuable information for the differentiation from other diseases, particularly retinoblastoma. The authors present a review of the literature and an iconographic study of the imaging findings in patients with PHPV. (author)

  20. Proteinas do liquido cefalorraqueano: I. Estudo comparativo entre metodos de concentração

    Directory of Open Access Journals (Sweden)

    Lucia M. Singer Vermes

    1983-03-01

    Full Text Available No intuito de escolher entre métodos de concentração, aplicáveis ao LCR, aquele que, não provocando desnaturação de proteínas, seja o mais exato, preciso e de fácil aplicação em laboratórios de rotina, foram estudados quatro procedimentos: diálise contra solução de goma-arábica, centrífugo-ultrafiltração, absorção de substâncias de baixo peso molecular por gel seco de poliacrilamida e ultrafiltração sob pressão positiva. Concluiu-se que a diálise contra solução de goma-arábica, por ser preciso, relativamente exato, simples e pouco oneroso, é o mais satisfatório dentre os métodos estudados.

  1. La scrittura è terapeutica? Il metodo autobiografico e la composizione del sé

    Directory of Open Access Journals (Sweden)

    Nicola Ghezzani

    2010-02-01

    Full Text Available Far da sé il proprio ritratto biografico significa, in rapporto a queste alienazioni, sfidare i demoni della compiacenza e della connivenza con l’altro, quindi porre il rifiuto, l’opposizione e quindi il vuoto, il nulla, l’assenza come base sulla quale veder apparire le proprie scene e le proprie passioni. Solo se non devo rispondere di me stesso a nessun altro che a me stesso, io sono nella condizione di cogliermi nella mia delusione fondamentale, nell’opposizione frontale che ho verso il mondo o verso i valori recepiti, nella mia protesta di riscatto dalla soggezione, nelle mie istanze di vendetta, di cui avverto insieme la violenza apocalittica e la colpa morale, quindi posso valutare quanto sono trascinato da passioni, reso nemico agli altri e a me stesso, e quanto posso riequilibrare il mio essere sulla base di una valutazione intima, sentita, ponderata di ogni lato contrapposto della mia identità.

  2. METODO PROPUESTO PARA LA PREDICCION DE TENSIONES ADMISIBLES EN ZAPATAS CIMENTALDAS EN ARENAS

    OpenAIRE

    DIAZ SEGURA; EDGAR GIOVANNY; DIAZ SEGURA; EDGAR GIOVANNY

    2010-01-01

    La evidencia experimental ha demostrado que la mayoría de las metodologías actuales no son capaces de predecir las cargas de diseño de zapatas en suelos no cohesivos con un grado aceptable de precisión. En el presente estudio se propone un método sencillo y realista para estimar la carga de diseño de zapatas rígidas cimentadas en arenas sometidas a una carga estática vertical. Se adoptó como criterio de diseño el propuesto por Terzaghi et al. (1996), basado en limitar a 16 mm e...

  3. METODO PROPUESTO PARA LA PREDICCION DE TENSIONES ADMISIBLES EN ZAPATAS CIMENTADAS EN ARENAS

    OpenAIRE

    DIAZ SEGURA, EDGAR GIOVANNY; DIAZ SEGURA, EDGAR GIOVANNY

    2010-01-01

    La evidencia experimental ha demostrado que la mayoría de las metodologías actuales no son capaces de predecir las cargas de diseño de zapatas en suelos no cohesivos con un grado aceptable de precisión. En el presente estudio se propone un método sencillo y realista para estimar la carga de diseño de zapatas rígidas cimentadas en arenas sometidas a una carga estática vertical. Se adoptó como criterio de diseño el propuesto por Terzaghi et al. (1996), basado en limitar a 16 mm el asentamiento ...

  4. Imperfect twinning - evaluation by imaging methods; Gemelidade imperfeita - avaliacao pelos metodos de imagem

    Energy Technology Data Exchange (ETDEWEB)

    Teixeira, Arildo Correa; Julio, Hamilton [Parana Univ., Curitiba, PR (Brazil). Hospital das Clinicas. Disciplina de Ginecologia e Obstetricia; Mazer, Sergio; Urban, Linei Augusta Brolini Delle [Parana Univ., Curitiba, PR (Brazil). Hospital das Clinicas. Servico de Radiologia]. E-mail: lineiurban@hotmail.com

    2003-02-01

    Conjoined twins are rare malformations and a challenge for both radiologists and pediatric surgeons. Antenatal evaluation is essential for the identification of anatomic fusions and other associated abnormalities, which will enable an adequate surgical planning and the assessment of fetal prognosis. The authors present the clinical and imaging findings of thoracopagus twins, joined by the anterior portion of the thorax, sharing the heart and the liver. Diagnosis was made by ultrasonography and confirmed with fetal magnetic resonance imaging. (author)

  5. Um metodo para modelagem de exceções em desenvolvimento baseado em componentes

    OpenAIRE

    Patrick Henrique da Silva Brito

    2005-01-01

    Resumo: Devido a grande popularização do Desenvolvimento Baseado em Componentes (DBC), ele vem sendo empregado inclusive no desenvolvimento de sistemas computacionais críticos. O emprego do DBC na construção de sistemas confiáveis evidencia a necessidade de se desenvolver componentes de software que sejam robustos e que possuam uma garantia maior do seu funcionamento correto. Tratamento de exceções é uma técnica bastante conhecida para a verificação e tratamento de erros em sistemas de softwa...

  6. Conocimiento y uso de metodos anticonceptivos por la poblacion femenina de una zona de salud

    Directory of Open Access Journals (Sweden)

    Maroto de Agustín Alicia

    1998-01-01

    Full Text Available FUNDAMENTO: El uso de métodos anticonceptivos está en relación, entre otros, con factores demográficos, sociales, económicos, educativos e ideológicos. El objetivo de este trabajo es conocer qué métodos anticonceptivos conocen las mujeres en edad fértil, así como la prevalencia de su uso. MÉTODOS: A partir del listado de tarjeta sanitaria se seleccionaron mediante muestreo sistemático 389 de las 5800 mujeres en edad fértil (15-45 años asignadas a un centro de salud. Previo envío de una carta, comunicando el motivo del estudio, se contactó telefónicamente con ellas para la realización de una encuesta, la cual incluía preguntas acerca del conocimiento y uso de métodos anticonceptivos, características socioculturales y actividad sexual. Las mujeres que no tenían teléfono fueron citadas en el centro de salud. RESULTADOS: Se contactó con 178 mujeres, de las que participaron 166 (tasa de respuesta de 42,7%. De ellas utilizaban algún método anticonceptivo 86 (51,8%; IC:44,2-59,4%. Sin embargo, entre mujeres con riesgo de embarazo no deseado, la prevalencia de uso era del 70,5% (IC: 62,4-78,6%, destacando el hecho de que en el grupo de mujeres de 40 a 45 años sólo utilizaran anticonceptivos el 45,4%, con una frecuencia significativamente inferior a los otros grupos de edad. Los métodos más conocidos eran el preservativo (90,4%, los contraceptivos orales (89,2% y el dispositivo intrauterino (78,3%, siendo escaso el conocimiento de otros métodos. CONCLUSIONES: La tasa de utilización de métodos anticonceptivos en mujeres con riesgo de embarazo no deseado es aceptable, si bien entre 40 y 45 años es llamativamente baja. Los métodos más conocidos son el preservativo, los contraceptivos orales y el dispositivo intrauterino.

  7. Modelizacion del secado de madera de #Pinus pseudostrobus# utilizando el metodo de la curva caracteristica

    OpenAIRE

    Hernandez Bautista, Emilio; Sandoval Torres, Sadoth; Rodriguez Ramirez, Juan; Velasco Cruz, Omar Ali

    2010-01-01

    Actuellement il existe une augmentation de la demande en produits forestiers au niveau mondial. Le séchage est une étape importante à l'intérieur du processus de transformation du bois, une opération qui bonifie sa qualité et accroît sa valeur. L'article présente l'analyse des expérimentations de séchage du bois Pinus pseudostrobus par convection d'air chaud, avec l'objectif de modéliser les cinétiques de séchage en utilisant la méthode de la courbe caractéristique de séchage. Les expérimenta...

  8. Privatumo ir saugos lygio vertinimo interneto svetainėse metodo parengimas ir taikymas

    OpenAIRE

    Kiškis, Tadas

    2012-01-01

    The purpose of Master’s Thesis is to prepare internet browsers users’ protection methods which would safeguard them from the attacks caused by social engineering and receivable data. Adding to safety from unsolicited information spread over the internet. The work examines privacy and security questions, existing and proposed internet security safeguard methods, recommendations and main initiatives. Designed methodology and implemented privacy and security level internet assessment system. Cre...

  9. New method for protection of parallel generator; Novo metodo para protecao do gerador em paralelismo

    Energy Technology Data Exchange (ETDEWEB)

    Silva, M R.C. da [Elfa-Seg Eletronica Ltda. (Brazil)

    1988-07-01

    The protection of synchronous machinery, especially generators working in parallel with the pertaining electric power utility have been extensively discussed specially because of the growing importance of co-generation in Brazil. This work discusses existing efficient methods and suggests new ways of proceeding this protection. 8 refs., 2 figs.

  10. Gastroesophageal reflux - correlation between diagnostic methods; Refluxo gastroesofagico - correlacao entre metodos diagnosticos

    Energy Technology Data Exchange (ETDEWEB)

    Cruz, Maria das Gracas de Almeida; Penas, Maria Exposito; Fonseca, Lea Mirian Barbosa [Universidade Federal, Rio de Janeiro, RJ (Brazil). Faculdade de Medicina. Dept. de Radiologia-Medicina Nuclear; Lemme, Eponina Maria O. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Faculdade de Medicina. Dept. de Clinia Medica-Gastroenterologia; Martinho, Maria Jose Ribeiro [Hospital Universitario Clementino Fraga Filho, Rio de Janeiro, RJ (Brazil). Servico de Medicina Nuclear

    1999-02-01

    A group of 97 individuals with typical symptoms of gastroesophageal reflux disease (GERD) was submitted to gastroesophageal reflux scintigraphy (GES) and compared to the results obtained from endoscopy, histopathology and 24 hours pHmetry. Twenty-four healthy individuals were used as a control group and they have done only the GERS. The results obtained showed that: (a) the difference in the reflux index (RI) for the control group and the sick individuals was statistically significant (p < 0.0001); (b) the correlation between GERS and the other methods showed the following results: sensitivity, 84%; specificity, 95%; positive predictive value, 98%; negative predictive value, 67%; accuracy, 87%. We have concluded that the scintigraphic method should be used to confirm the diagnosis of GERD and also recommended as initial investiative procedure. (author)

  11. Porous oxides synthesized by the combustion method; Oxidos porosos sintetizados por el metodo de combustion

    Energy Technology Data Exchange (ETDEWEB)

    Lugo L, V

    2005-07-01

    The result of this work, seeks to be a contribution for the treatment of radioactive wastes, with base to the sorption properties that present those porous oxides, synthesized by a method that allows to increase the sorption capacity. The main objective of the present investigation has been the modification of the structural characteristics of the oxides of Fe, Mg and Zn to increase its capacity of sorption of {sup 60} Co in particular. It was studied the effect of the synthesis method by combustion in the inorganic oxides; the obtained solids were characterized using the following techniques: X-ray diffraction (XRD), scanning electron microscopy (SEM), semiquantitative elementary analysis by Dispersive energy spectroscopy (EDS) and determination of surface area by the Brunauner-Emmett-Teller method (BET). Also was carried out batch type experiments for the sorption of Co{sup 2+}, with the purpose of studying the sorption capacity of each one of the prepared oxides. In accordance with that previously exposed, the working plan that was carried out in this investigation is summarized in the following stages: 1. Preparation of inorganic oxides by two different methods, studying the effect of the temperature in the synthesis process. 2. Characterization of the inorganic oxides by XRD, by means of which those were chosen the solids with better properties. 3. Characterization of the inorganic oxides by SEM and EDS where it was studied the morphology of the synthesized materials and the semiquantitative elemental composition. 4. Realization of a sorption experiment type Batch with non radioactive Co{sup 2+} to simulate the sorption of {sup 60} Co and determination of the sorption capacity by means of neutron activation of the non radioactive cobalt. 5. Determination of the surface area by the (BET) technique of the inorganic oxides with better sorption properties. (Author)

  12. Geostatistical methods for the integrated information; Metodos geoestadisticos para la integracion de informacion

    Energy Technology Data Exchange (ETDEWEB)

    Cassiraga, E F; Gomez-Hernandez, J J [Departamento de Ingenieria Hidraulica y Medio Ambiente, Universidad Politecnica de Valencia, Valencia (Spain)

    1996-10-01

    The main objective of this report is to describe the different geostatistical techniques to use the geophysical and hydrological parameters. We analyze the characteristics of estimation methods used in others studies.

  13. Sample Preparations Used in Biomedical Research and Training at the Special Training Division of the Oak Ridge Institute of Nuclear Studies; Methodes de Preparation d'Echantillons Employees dans la Recherche et la Formation Biologiques et Medicales a la Division de Formation Speciale de l'Institut d'Etudes Nucleaires d'Oak Ridge; Prigotovlenie obraztsov dlya biomeditsinskikh issledovanij i dlya uchebnykh tselej v otdele spetsial'noj podgotovki okridzhskogo instituta yadernykh issledovanii; Metodos de Preparacion de Muestras Aplicados en las Investigaciones Biomedicas y en la Capacitacion Profesional de la Division de Formacion Especial del Instituto de Estudios Nucleares de Oak Ridge

    Energy Technology Data Exchange (ETDEWEB)

    Akers, L. K. [Oak Ridge Institute of Nuclear Studies, Oak Ridge, TN (United States)

    1965-10-15

    mixtes. Les mesures sont faites a l'aide d'une serie de compteurs a grilles Fairstein-Frisch relies a un analyseur a 512 canaux pour l'enregistrement simultane de plusieurs spectres. On utilise en outre des detecteurs a semi-conducteurs. L'auteur compare les donnees fournies par ces derniers aux resultats obtenus a l'aide de detecteurs a grilles. (author) [Spanish] En el desarrollo de los programas de investigacion y de capacitacion profesional de la Division de Formacion Especial se utiliza una amplia variedad de metodos de preparacion de muestras, que abarcan desde el empleo de sencillos portafuentes a base de materiales tales como metal, cartulina y plasticos hasta el de dispositivos de precipitacion que utilizan soportes de acero inoxidable y fibra de vidrio y portafuentes especiales para el recuento por centelleo laquido. Admas de estas tecnicas, se han elaborado diversos procedimientos de interes especial para la resolucion de problemas biomedicos. Uno de los mas importantes consiste en el empleo de una sintesis catalitica del benceno que se ha perfeccionado hasta el punto de que se obtiene un rendimiento global superior al 90%. Esta sintesis puede aplicarse a los compuestos de carbono de interes para los experimentos con indicadores de baja actividad y problemas de determinacion de edades. Dado que la sintesis entrana la produccion de anhidrido carbonico en una fase y la hidratacion de carburo metalico en otra, puede utilizarse ya sea para medir {sup 14}Co o {sup 3}H o ambos en experimentos con marcacion doble. Se realiza una labor considerable en la esfera del analisis por activacion de sustancias biologicas, particularmente en la ejecucion de los programas radioecologicos de la division. Se describen tecnicas especiales para la preparacion de estas sustancias destinadas al analisis por activacion y otras operaciones radioquimicas. Dado que sigue siendo dificil la cuestion de la resolucion en la espectroscopia alfa, el grupo da estudios oceanograficos y

  14. Comparative analysis to determine asphalt density and content, using nuclear and traditional methods; Analisis comparativo para la determinacion de densidad y contenido de asfalto, mediante metodo nuclear y metodo tradicional

    Energy Technology Data Exchange (ETDEWEB)

    Margffoy S, F R; Robayo S, A M

    1989-07-01

    Quality control for flex pavement construction in Colombia for asphaltic mix, as well as for granular and granular sub base layers is made by means of methods that does not guarantee the quality of the job, due to the difficult execution of tests, which impede more to be done or due to inherent problems of the test process. Thanks to the inherent characteristics and advantages of nuclear techniques, those become the optimal alternative to this quality control job. The present research project has been developed with the objective of justifying the use of new technologies applied to road construction; making a comparative analysis between traditional methods used in our country and nuclear techniques that have been using in United States with great success in quality control in road construction.

  15. Wielandt method applied to the diffusion equations discretized by finite element nodal methods; Metodo de Wielandt aplicado a las ecuaciones de difusion discretizadas por metodos nodales de elemento finito

    Energy Technology Data Exchange (ETDEWEB)

    Mugica R, A.; Valle G, E. del [IPN, ESFM, 07738 Mexico D.F. (Mexico)]. e-mail: mugica@esfm.ipn.mx

    2003-07-01

    Nowadays the numerical methods of solution to the diffusion equation by means of algorithms and computer programs result so extensive due to the great number of routines and calculations that should carry out, this rebounds directly in the execution times of this programs, being obtained results in relatively long times. This work shows the application of an acceleration method of the convergence of the classic method of those powers that it reduces notably the number of necessary iterations for to obtain reliable results, what means that the compute times they see reduced in great measure. This method is known in the literature like Wielandt method and it has incorporated to a computer program that is based on the discretization of the neutron diffusion equations in plate geometry and stationary state by polynomial nodal methods. In this work the neutron diffusion equations are described for several energy groups and their discretization by means of those called physical nodal methods, being illustrated in particular the quadratic case. It is described a model problem widely described in the literature which is solved for the physical nodal grade schemes 1, 2, 3 and 4 in three different ways: to) with the classic method of the powers, b) method of the powers with the Wielandt acceleration and c) method of the powers with the Wielandt modified acceleration. The results for the model problem as well as for two additional problems known as benchmark problems are reported. Such acceleration method can also be implemented to problems of different geometry to the proposal in this work, besides being possible to extend their application to problems in 2 or 3 dimensions. (Author)

  16. The disc method. A new method for selecting facilitations in flocculating sludge to be dewatered in centrifuges; Metodo de disco. Un nuevo metodo para la seleccion de floculantes en la floculacion de lodos a deshidratar en centrifugas

    Energy Technology Data Exchange (ETDEWEB)

    Canga Rodriguez, J.; Gutierrez Lavin, A.

    2002-07-01

    An experimental protocol was designed at a laboratory scale, in view of achieving the selection with different poly electrolytes related to the chemical conditioning (flocculation) of sewage sludge before dewatering it in a drying centrifuge. The method is based on a new parameter of quality of the formed floc, which measures its compaction when is submitted to a fix external strength. Some experimental tests have been introduced, whose results are numbers, avoiding all subjective aspects related to direct observation of flocs. (Author) 8 refs.

  17. Proposta de metodo de gerenciamento de processos administrativos para organizações prestadoras de serviços

    OpenAIRE

    Benigno Roberto Zaki

    2009-01-01

    Resumo: Desde a metade do século XX e neste início do século XXI, as empresas buscam aumentar a produtividade e melhorar a qualidade de seus produtos e serviços. Para uma organização, muito mais do que a liderança no seu mercado de atuação é a sua capacidade de se manter competitiva. A busca da vantagem competitiva perante o mercado está em satisfazer as expectativas do cliente e implementar com êxito uma série de exigências em termos de eficiência no processo produtivo. O desenvolvimento des...

  18. Trends in the analytical methods for water analysis; Tendencias de los metodos analiticos para el analisis del agua

    Energy Technology Data Exchange (ETDEWEB)

    Tortajada-Genero, L. A.; Campins-Falco, P. [Universidad de Valencia (Spain)

    2003-07-01

    The technological and methodological advances have provided and evolution of analytical chemistry, specially in the area of water analysis. There area wide variety of problems for this kind of analysis, as result of the high number of possible objectives. They involve from complex environmental studies to routine control of a physical-chemical parameter. Additionally, the variety of analysis to analyse is increasing as in total number as in complexity terms. The response has been the appearance of a high number of analytical methods. Some guidelines and recommendations have been described together with different strategies for quality assurance. In this paper, a review of the last analytical methods described in the scientific references for determinations in water was realised. The evolution and future perspectives were also studied. (Author) 16 refs.

  19. Silicon dioxide obtained by Polymeric Precursor Method; Obtencao de dioxido de silicio pelo Metodo dos Precursores Polimericos

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, C.T.; Granado, S.R.; Lopes, S.A.; Cavalheiro, A.A., E-mail: cinthia_quimica@hotmail.com [Universidade Estadual de Mato Grosso do Sul (CPTREN/UEMS), Navirai, MS (Brazil). Centro de Pesquisas Tecnologicas em Recursos Naturais

    2011-07-01

    The Polymeric Precursor Method is able for obtaining several oxide material types with high surface area even obtained in particle form. Several MO{sub 2} oxide types such as titanium, silicon and zirconium ones can be obtained by this methodology. In this work, the synthesis of silicon oxide was monitored by thermal analysis, XRD and surface area analysis in order to demonstrate the influence of the several synthesis and calcining parameters. Surface area values as higher as 370m2/g and increasing in the micropore volume nm were obtained when the material was synthesized by using ethylene glycol as polymerizing agent. XRD analysis showed that the material is amorphous when calcinated at 600°C in despite of the time of calcining, but the material morphology is strongly influenced by the polymeric resin composition. Using Glycerol as polymerizing agent, the pore size increase and the surface area goes down with the increasing in decomposition time, when compared to ethylene glycol. (author)

  20. Modern analytic methods applied to the art and archaeology; Metodos analiticos modernos aplicados al arte y la arqueologia

    Energy Technology Data Exchange (ETDEWEB)

    Tenorio C, M. D.; Longoria G, L. C., E-mail: dolores.tenorio@inin.gob.m [ININ, Departamento de Quimica, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2010-07-01

    The interaction of diverse areas as the analytic chemistry, the history of the art and the archaeology has allowed the development of a variety of techniques used in archaeology, in conservation and restoration. These methods have been used to date objects, to determine the origin of the old materials and to reconstruct their use and to identify the degradation processes that affect the integrity of the art works. The objective of this chapter is to offer a general vision on the researches that have been realized in the Instituto Nacional de Investigaciones Nucleares (ININ) in the field of cultural goods. A series of researches carried out in collaboration with national investigators and of the foreigner is described shortly, as well as with the great support of degree students and master in archaeology of the National School of Anthropology and History, since one of the goals that have is to diffuse the knowledge of the existence of these techniques among the young archaeologists, so that they have a wider vision of what they could use in an in mediate future and they can check hypothesis with scientific methods. (Author)

  1. Experimental method for calculation of effective doses in interventional radiology; Metodo experimental para calculo de dosis efectivas en radiologia intervencionista

    Energy Technology Data Exchange (ETDEWEB)

    Herraiz Lblanca, M. D.; Diaz Romero, F.; Casares Magaz, O.; Garrido Breton, C.; Catalan Acosta, A.; Hernandez Armas, J.

    2013-07-01

    This paper proposes a method that allows you to calculate the effective dose in any interventional radiology procedure using an anthropomorphic mannequin Alderson RANDO and dosimeters TLD 100 chip. This method has been applied to an angio Radiology procedure: the biliary drainage. The objectives that have been proposed are: to) put together a method that, on an experimental basis, allows to know dosis en organs to calculate effective dose in complex procedures and b) apply the method to the calculation of the effective dose of biliary drainage. (Author)

  2. Summary of ceramic pigments by polymer precursors Pechini method; Sintese de pigmentos ceramicos pelo metodo dos precursores polimericos

    Energy Technology Data Exchange (ETDEWEB)

    Silva, E.M. da; Galvao, S.B.; Paskocimas, C.A., E-mail: everlania_siva@yahoo.com.b [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil)

    2010-07-01

    In this work were synthesized nitrate chromium nitrate and iron-doped titanium oxide by the polymeric precursor method, for application as ceramic pigments. The stains were developed between the temperatures 700 deg C to 1000 deg C, in green for chromium oxide and orange for iron. Noticing an increase of its opacity by increasing temperature. Characterization by thermogravimetry (TG) showed strong thermo decomposition from 355 deg C for the chromium oxide and thermo decomposition gradual for the iron. By analysis of X-ray diffraction revealed the formation of crystalline phases as Iron Titanate (FeTiO3) and Chrome Titanate (CrTiO3), respectively. The scanning electron microscopy showed the formation of rounded particles for both oxides. Thus, the synthesized oxides were within the requirements to be applied as pigments and shown to be possible to propose its use in ceramic materials. (author)

  3. In service inspection of pipes based on risk methods; Inspeccion en servicio de tuberias basada en metodos de riesgo

    Energy Technology Data Exchange (ETDEWEB)

    Mendoza G, G.; Viais J, J.; Carmona C, M. [ININ, Centro Nuclear ' Dr. Nabor Carrillo Flores' , Carretera Mexico Toluca, S/N. La Marquesa, Ocoyoacac, Mexico, C. P. 52750 (Mexico)]. e-mail: gmg@nuclear.inin.mx

    2006-07-01

    The politics of the Nuclear Regulatory Commission (by its initials in English NRC) of the United States of America on the use of the Probabilistic Safety Analysis (PSA) in activities of nuclear regulation it foments the use of this analysis technique to improve the decisions making, to reduce the unnecessary work in maintenance aspects, inspection and tests and to improve the regulatory efficiency. The inspection programs in service (ISI by its initials in English) developed by the American Society of Mechanical Engineers (by its initials in English ASME) it has been the one primary mechanism to prove the mechanical equipment in plants of nuclear energy, these programs indeed have been carried out in plants of nuclear energy by more of two decades. Their purpose is to identify the conditions, such as indications of cracks that are precursory of flights and ruptures which violate the integrity principles of the pressure frontier. The inspection in service activities include ultrasonic tests, surface tests and penetrating liquids test, also activities that include the scaffolds construction, removal of insulations and welding polishing. The inspections in service every 18 months during the times outside of service are executed. One of the objectives is to lower the costs of the inspections during the times outside of service and to reduce the exposure to the radiation by part of the personnel during these times out for inspections, while it is increased or it maintains the personnel's safety and the reliability. As part of the methodology a pipe segment is selected for which a fault in any point has the same consequences, being calculated the fault probability of the tube using the dimensions of the segment. In this work the inspection in service methodology is applied based on risk to an aspersion system of low pressure of the Laguna Verde Nucleo electric Central. For this system a reduction in the number of welding to inspect of 103 to only 15 is obtained, recommending only flight monitoring and pressure and flight tests for 13 considered segments of low risk. With the above-mentioned a substantial saving is obtained in the costs by inspection for the plant, avoiding the potential personnel's lesions by means of the reduction of the construction of scaffolds, removal of asbestos, removal of insulations and welding polishing. (Author)

  4. Tools for building Breast Cancer CAD methods; Herramientas para elaborar metodos de CAD del cancer de mama

    Energy Technology Data Exchange (ETDEWEB)

    Diaz-Herrero, G.; Franco-Valiente, J. M.; Suarez-Ortega, C.; Rubio del Solar, M.; Ramos-Pollam, R.; Guevara-Lopez, M. A.; Gonzalez de Posada, N.; Ramos, I.; Loureiro, J.

    2011-07-01

    This paper describes the main results of the collaboration currently ongoing between CETA-CIEMAT and the Faculty of Engineering at the University of Porto. It introduces the Mammography image Workstation for Analysis and Diagnosis (MIWAD) and the data analysis processes through which Grid infrastructures are used to develop Breast Cancer Computer-Aided Diagnosis (CAD) methods.MIWAD is a novel integrated software framework that integrates a specialized graphical user interface combining digital image processing, pattern recognition and artificial intelligence techniques. This paper describes its successful application in a pilot experience, on the first Portuguese Breast Cancer Digital Repository. (Author)

  5. Approximation of the Doppler broadening function by Frobenius method; Aproximacao da funcao de alargamento doppler atraves do metodo de Frobenius

    Energy Technology Data Exchange (ETDEWEB)

    Palma, Daniel A.P. [Centro Federal de Educacao Tecnologica de Quimica de Nilopolis/RJ (CEFET), RJ (Brazil)]. E-mail: dpalma@cefeteq.br; Martinez, Aquilino S.; Silva, Fernando C. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Programa de Engenharia Nuclear]. E-mail: aquilino@lmp.ufrj.br; fernando@lmn.con.ufrj.br

    2005-07-01

    An analytical approximation of the Doppler broadening function {psi}(x,{xi}) is proposed. This approximation is based on the solution of the differential equation for {psi}(x,{xi}) using the methods of Frobenius and the parameters variation. The analytical form derived for {psi}(x,{xi}) in terms of elementary functions is very simple and precise. It can be useful for applications related to the treatment of nuclear resonances mainly for the calculations of multigroup parameters and self-protection factors of the resonances, being the last used to correct microscopic cross-sections measurements by the activation technique. (author)

  6. A proactive method for safety management in nuclear facilities; Um metodo proativo para gerenciamento da seguranca em instalacoes nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Grecco, Claudio Henrique dos Santos; Carvalho, Paulo Victor Rodrigues de; Santos, Isaac Antonio Luquetti dos, E-mail: grecco@ien.gov.br, E-mail: paulov@ien.gov.br, E-mail: luquetti@ien.gov.br [Instituto de Engenharia Nuclear (IEN/CNEN/RJ), Rio de Janeiro, RJ (Brazil). Div. de Instrumentacao e Confiabilidade Humana

    2014-07-01

    Due to the modern approach to address the safety of nuclear facilities which highlights that these organizations must be able to assess and proactively manage their activities becomes increasingly important the need for instruments to evaluate working conditions. In this context, this work presents a proactive method of managing organizational safety, which has three innovative features: 1) the use of predictive indicators that provide current information on the performance of activities, allowing preventive actions and not just reactive in safety management, different from safety indicators traditionally used (reactive indicators) that are obtained after the occurrence of undesired events; 2) the adoption of resilience engineering approach in the development of indicators - indicators are based on six principles of resilience engineering: top management commitment, learning, flexibility, awareness, culture of justice and preparation for the problems; 3) the adoption of the concepts and properties of fuzzy set theory to deal with subjectivity and consistency of human trials in the evaluation of the indicators. The fuzzy theory is used primarily to map qualitative models of decision-making, and inaccurate representation methods. The results of this study aim an improvement in performance and safety in organizations. The method was applied in a radiopharmaceutical shipping sector of a nuclear facility. The results showed that the method is a good monitoring tool objectively and proactively of the working conditions of an organizational domain.

  7. Sintese fotoquimica de polipirrol em membranas microporosas de PVDF : um novo metodo para obter compositos condutores eletricos

    OpenAIRE

    Ruth Marlene Campomanes Santana

    1995-01-01

    Resumo: Este trabalho descreve em linhas gerais um novo método de obter compósitos condutores de polipirrol (PPy)/Poli(fluoreto de vinilideno) (PVDF), polimerização via luz UV induzida em presença de um adequado fotogerador de ácido (PAG), compostos tais como os sais de Ferro-areno e Trifenil sulfônio ou compostos geradores orgânicos tal como a triazina clorinada. Estudos Gravimétricos confirmados por Análise Termogravimé-trico (TGA), tem mostrado que o rendimento da polimerização insidente n...

  8. Manual method for dose calculation in gynecologic brachytherapy; Metodo manual para o calculo de doses em braquiterapia ginecologica

    Energy Technology Data Exchange (ETDEWEB)

    Vianello, Elizabeth A.; Almeida, Carlos E. de [Instituto Nacional do Cancer, Rio de Janeiro, RJ (Brazil); Biaggio, Maria F. de [Universidade do Estado, Rio de Janeiro, RJ (Brazil)

    1998-09-01

    This paper describes a manual method for dose calculation in brachytherapy of gynecological tumors, which allows the calculation of the doses at any plane or point of clinical interest. This method uses basic principles of vectorial algebra and the simulating orthogonal films taken from the patient with the applicators and dummy sources in place. The results obtained with method were compared with the values calculated with the values calculated with the treatment planning system model Theraplan and the agreement was better than 5% in most cases. The critical points associated with the final accuracy of the proposed method is related to the quality of the image and the appropriate selection of the magnification factors. This method is strongly recommended to the radiation oncology centers where are no treatment planning systems available and the dose calculations are manually done. (author) 10 refs., 5 figs.

  9. Desulfurization of fuel oils using an advanced oxidation method; Desulfuracion de combustibles usando un metodo de oxidacion avanzada

    Energy Technology Data Exchange (ETDEWEB)

    Flores Velazquez, Roberto; Rodas Grapain, Arturo [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2008-07-01

    In the present work, the oxidative desulfurization of fuel oils assisted by ultrasound was analyzed. It was studied the effect of hydrogen peroxide concentration, the fuel oil to aqueous solution volumetric ratio, and type of catalyst. The Fenton-like catalysts studied were ferric chloride and copper sulfate. [Spanish] En esta investigacion se analiza la desulfuracion oxidativa de combustoleo asistida con ultrasonido. Tambien se estudia el efecto de la concentracion de peroxido de hidrogeno (H{sub 2}O{sub 2}), la relacion volumetrica combustoleo/solucion acuosa y el tipo de catalizador. Los catalizadores tipo Fenton que se estudiaron fueron el cloruro ferrico (FeCl{sub 3}) y el sulfato de cobre (CuSO{sub 4}).

  10. Application of numerical analysis methods to thermoluminescence dosimetry; Aplicacion de metodos de analisis numerico a la dosimetria por termoluminiscencia

    Energy Technology Data Exchange (ETDEWEB)

    Gomez Ros, J M; Delgado, A

    1989-07-01

    This report presents the application of numerical methods to thermoluminescence dosimetry (TLD), showing the advantages obtained over conventional evaluation systems. Different configurations of the analysis method are presented to operate in specific dosimetric applications of TLD, such as environmental monitoring and mailed dosimetry systems for quality assurance in radiotherapy facilities. (Author) 10 refs.

  11. A new method for the coefficients of the characteristic polynomial; Un metodo nuevo para los coeficientes del polinomio caracteristico

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, H.E. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2006-07-01

    In linear algebra, one can associate an equation to each square matrix: its characteristic equation or secular equation. Starting from this equation, the one characteristic polynomial that codes several important properties of the matrix is obtained: its own values, it determinant and it appearance. The first method to calculate those coefficients of this polynomial were proposed by the french astronomer Urbain Jean Joseph Le Verrier (1811-1877), from then on, many methods have intended to calculate these coefficients. In this work the author proposes a new one method and a bibliographical citation is given where the calculations with others methods that know each other for it, taking like reference the matrix used by Le Verrier are explained. It was concluded that it here proposed, besides being the only mexican method that is knew, has the advantage of being very easy of understanding and of calculating well, in the operations that it carries out, it doesn't use the division and it avoids fractions in matrices whose entrances are whole. This has a great importance for their use in the classroom for their great didactic value and in nuclear reactors and Genetic Engineering. (Author)

  12. Pharyngeal transit time measured by scintigraphic and biomagnetic method; Tempo de transito faringeano medido atraves dos metodos cintilografico e biomagnetico

    Energy Technology Data Exchange (ETDEWEB)

    Miquelin, C.A.; Braga, F.J.H.N.; Baffa, O. [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Faculdade de Filosofia, Ciencias e Letras. Dept. de Fisica; Dantas, R.O.; Oliveira, R.B. [Faculdade de Medicina de Ribeirao Preto, SP (Brazil)

    1996-12-31

    A comparative evaluation between scintigraphic and biomagnetic method to measure the pharyngeal transit is presented. Three volunteers have been studied. The aliment (yogurt) was labeled with {sup 9}9{sup m} Technetium for the scintigraphic test and with ferrite for the biomagnetic one. The preliminary results indicate a difference between the values obtained, probably due to the biomagnetic detector resolution 3 refs., 2 figs., 1 tab.

  13. Automation of the method gamma of comparison dosimetry images; Automatizacion del metodo gamma de comparacion de imagenes dosimetricas

    Energy Technology Data Exchange (ETDEWEB)

    Moreno Reyes, J. C.; Macias Jaen, J.; Arrans Lara, R.

    2013-07-01

    The objective of this work was the development of JJGAMMA application analysis software, which enables this task systematically, minimizing intervention specialist and therefore the variability due to the observer. Both benefits, allow comparison of images is done in practice with the required frequency and objectivity. (Author)

  14. Metodos estadisticos empleados en los articulos originales publicados sobre tabaquismo en cuatro revistas medicas espanõlas (1985-1996

    Directory of Open Access Journals (Sweden)

    García López José Antonio

    2000-01-01

    Full Text Available Fundamento: Siendo el tabaquismo un tema prioritario de investigación y habiéndose incrementado el uso de técnicas estadísticas en las publicaciones biomédicas, se describen las técnicas estadísticas utilizadas y se cuantifica la accesibilidad estadística en los artículos originales sobre tabaquismo publicados en cuatro revistas médicas españolas. Métodos: Estudio descriptivo retrospectivo de los 154 artículos originales sobre tabaquismo publicados en las revistas Atención Primaria, Medicina Clínica (Barcelona, Revista Española de Salud Pública y Revista Clínica Española, en el período de 1985 a 1996. Un único observador codificó las técnicas estadísticas en 14 categorías de acuerdo con la clasificación elaborada por Carré et al (1995 a partir de la clasificación establecida por Emerson y Colditz (1983. Para el estudio de la accesibilidad estadística se estableció como referencia el conocimiento de técnicas bivariables, hasta regresión lineal simple. Resultados: El 81,8% de los originales utilizaron la estadística inferencial. Las categorías estadísticas más frecuentemente utilizadas fueron las "Tablas de contingencia" (37,0%, "Estadística descriptiva" (18,2% y "Tablas de vida y análisis de supervivencia" (9,7%. Un lector familiarizado con técnicas bivariables tuvo acceso estadístico al 96,0% de los originales de Revista Española de Salud Pública, al 86,2% de Atención Primaria, al 66,7% de Medicina Clínica (Barcelona y al 33,3% de Revista Clínica Española. Este mismo lector tuvo acceso al 100% de los originales publicados en el trienio 1985-87 y al 68,1% en el 1994-96. Conclusiones: La utilización de técnicas estadísticas varía en función del tema y diseño de investigación, de la revista y del año de publicación. La disminución de la accesibilidad estadística hace necesario identificar el perfil del lector estándar en nuestro país para adaptar sus conocimientos a las exigencias de la literatura biomédica actual.

  15. Carbon/Clay nanostructured composite obtained by hydrothermal method; Compositos nanoestruturados carbono/argila obtidos por metodo hidotermico

    Energy Technology Data Exchange (ETDEWEB)

    Barin, G.B.; Bispo, T.S.; Gimenez, I.F.; Barreto, L.S., E-mail: gabriela.borin@gmail.co [Universidade Federal de Sergipe (UFS), Aracaju, SE (Brazil). Programa de Pos-Graduacao em Ciencia e Engenharia de Materiais; Souza Filho, A.G. [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Dept. de Fisica

    2010-07-01

    The development of strategies for converting biomass into useful materials, more efficient energy carrier and / or hydrogen storage is shown a key issue for the present and future. Carbon nanostructure can be obtained by severe processing techniques such as arc discharge, chemical deposition and catalyzed pyrolysis of organic compounds. In this study we used hydrothermal methods for obtaining nanostructured composites of carbon / clay. To this end, we used coir dust and special clays. The samples were characterized by infrared spectroscopy, X-ray diffraction and Raman. The presence of the D band at 1350 cm{sup -1} in the Raman spectrum shows the formation of amorphous carbon with particle size of about 8.85 nm. (author)

  16. Implementation of statistical analysis methods for medical physics data; Implementacao de metodos de analise estatistica para dados de fisica medica

    Energy Technology Data Exchange (ETDEWEB)

    Teixeira, Marilia S.; Pinto, Nivia G.P.; Barroso, Regina C.; Oliveira, Luis F., E-mail: mariliasilvat@gmail.co, E-mail: lfolive@oi.com.b, E-mail: cely_barroso@hotmail.co, E-mail: nitatag@gmail.co [Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, RJ (Brazil). Inst. de Fisica

    2009-07-01

    The objective of biomedical research with different radiation natures is to contribute for the understanding of the basic physics and biochemistry of the biological systems, the disease diagnostic and the development of the therapeutic techniques. The main benefits are: the cure of tumors through the therapy, the anticipated detection of diseases through the diagnostic, the using as prophylactic mean for blood transfusion, etc. Therefore, for the better understanding of the biological interactions occurring after exposure to radiation, it is necessary for the optimization of therapeutic procedures and strategies for reduction of radioinduced effects. The group pf applied physics of the Physics Institute of UERJ have been working in the characterization of biological samples (human tissues, teeth, saliva, soil, plants, sediments, air, water, organic matrixes, ceramics, fossil material, among others) using X-rays diffraction and X-ray fluorescence. The application of these techniques for measurement, analysis and interpretation of the biological tissues characteristics are experimenting considerable interest in the Medical and Environmental Physics. All quantitative data analysis must be initiated with descriptive statistic calculation (means and standard deviations) in order to obtain a previous notion on what the analysis will reveal. It is well known que o high values of standard deviation found in experimental measurements of biologicals samples can be attributed to biological factors, due to the specific characteristics of each individual (age, gender, environment, alimentary habits, etc). This work has the main objective the development of a program for the use of specific statistic methods for the optimization of experimental data an analysis. The specialized programs for this analysis are proprietary, another objective of this work is the implementation of a code which is free and can be shared by the other research groups. As the program developed since the method modeling through his implementation, this fact will allows that modifications and adaptations be accomplished any time at null cost

  17. A new method for the coefficients of the characteristic polynomial; Un metodo nuevo para los coeficientes del polinomio caracteristico

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, H E [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2006-07-01

    In linear algebra, one can associate an equation to each square matrix: its characteristic equation or secular equation. Starting from this equation, the one characteristic polynomial that codes several important properties of the matrix is obtained: its own values, it determinant and it appearance. The first method to calculate those coefficients of this polynomial were proposed by the french astronomer Urbain Jean Joseph Le Verrier (1811-1877), from then on, many methods have intended to calculate these coefficients. In this work the author proposes a new one method and a bibliographical citation is given where the calculations with others methods that know each other for it, taking like reference the matrix used by Le Verrier are explained. It was concluded that it here proposed, besides being the only mexican method that is knew, has the advantage of being very easy of understanding and of calculating well, in the operations that it carries out, it doesn't use the division and it avoids fractions in matrices whose entrances are whole. This has a great importance for their use in the classroom for their great didactic value and in nuclear reactors and Genetic Engineering. (Author)

  18. Probabilistic method for geotechnical design. Application to cohesive soils; Metodo probabilista de diseno geotecnico. Aplicacion en Suelos Cohesivos

    Energy Technology Data Exchange (ETDEWEB)

    Martinez Rodriguez, A. J.; Quevedo Sotolongo, G.

    2012-07-01

    A methodology to carry out a process of stochastic modelling in the calculation of the bearing capacity of a strip footing, on a purely cohesive soil, is proposed. the mentioned modelling is based on the application of Monte Carlo Simulation, which is more efficient, in terms of results, than classic procedures using deterministic models. These results will be the base for the application of a probabilistic design method, specifically the safety theory, starting by a statistical characterization of every random variables the impact in the problem, and it defines as a final result, a safety level for the structure, whose value will be the nearest to required safety in first limit state design or stability limit state, which is equivalent to 0.98. By this way it is established the design point of the structure according to safety design condition. (Author) 9 refs.

  19. Methods to identify and locate spent radiation sources; Metodos para la identificacion y localizacion de fuentes radiactivas gastadas

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-06-01

    The objective of this manual is to provide essential guidance to Member States with nuclear applications involving the use of a wide range of sealed radiation sources on the practical task of physically locating spent radiation sources not properly accounted for. Advice is also provided to render the located source safe on location. Refs, figs, tabs.

  20. Methods of calculus for neutron spectrometry in proportional counters; Metodos de calculo para espectrometria de neutrones en contadores proporcionales

    Energy Technology Data Exchange (ETDEWEB)

    Butragueno, J L; Blazquez, J B; Barrado, J M

    1976-07-01

    Response functions for cylindrical proportional counters with hydrogenated gases have been determined, taking in account only wall effect, by means of two independent calculus methods. One of them is a Monte Carlo application and the other one analytica at all. Results of both methods have been compared. (Author)

  1. PREVALENCIA DE BOCIO ENDEMICO POR EL METODO ECOGRAFICO, DETERMINACION DE YODURIAS y YODO EN SAL EN ESCOLARES DEL PARAGUAY.

    OpenAIRE

    Jara Y, Jorge A; Pretell, Eduardo A; Zaracho de Irazusta, Juana; Goetting, Sonia; Riveros, Claudia

    2004-01-01

    Paraguay, país mediterráneo ubicado en el corazón de America del Sur, con una superficie de 406.542 Km2 y con una población de 5,8 millones de habitantes importa toda la sal que consume de países cercanos como la Argentina, Brasil y Chile. En el presente estudio observacional, de tipo descriptivo utiliza el método ecográfico para determinar el tamaño y las características de la glándula tiroides, se examinaron 1034 escolares de ambos sexos de 13 distritos del país y fue realizado durante 3 me...

  2. Reconstruction of the limit cycles by the delays method; Reconstruccion de ciclos limite por el metodo de los retardos

    Energy Technology Data Exchange (ETDEWEB)

    Castillo D, R.; Ortiz V, J. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Calleros M, G. [CFE, CNLV, Alto Lucero, Veracruz (Mexico)]. e-mail: rcd@nuclear.inin.mx

    2003-07-01

    The boiling water reactors (BWRs) are designed for usually to operate in a stable-lineal regime. In a limit cycle the behavior of the one system is no lineal-stable. In a BWR, instabilities of nuclear- thermohydraulics nature can take the reactor to a limit cycle. The limit cycles should to be avoided since the oscillations of power can cause thermal fatigue to the fuel and/or shroud. In this work the employment of the delays method is analyzed for its application in the detection of limit cycles in a nuclear power plant. The foundations of the method and it application to power signals to different operation conditions are presented. The analyzed signals are: to steady state, nuclear-thermohydraulic instability, a non linear transitory and, finally, failure of a controller plant . Among the main results it was found that the delays method can be applied to detect limit cycles in the power monitors of the BWR reactors. It was also found that the first zero of the autocorrelation function is an appropriate approach to select the delay in the detection of limit cycles, for the analyzed cases. (Author)

  3. Obtaining hydroxyapatite coatings on titanium by the biomimetic method; Obtencion de recubrimientos de hidroxiapatita sobre titanio mediante el metodo biomimetico

    Energy Technology Data Exchange (ETDEWEB)

    Paz, A.; Martin, Y.; Pazos, L. M.; Parodi, M. B.; Ybarra, G. O.; Gonzalez, J. E.

    2011-07-01

    In this work, a study about the deposition of hydroxyapatite on a titanium substrate employing the biomimetic method is presented. A solution with high content of calcium and phosphorus (SCS) was used. In addition, activation of titanium with hydrogen peroxide and hydrochloric acid and a subsequent heat treatment was performed. The characterization of materials used and the coating obtained was carried out by Infrared Spectroscopy (FT-IR), X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDX). As a result of the activation processes a hydrated titanium oxide was formed. On the active surface, a coating of hydroxyapatite was obtained after a period of 24 h, which has a thickness of about 2-4 {mu}m. (Author) 21 refs.

  4. Laser cladding to select new glassy alloys; Uso do metodo de revestimento por laser na selecao de novas ligas vitreas

    Energy Technology Data Exchange (ETDEWEB)

    Medrano, L.L.O.; Afonso, C.R.M.; Kiminami, C.S.; Gargarella, P., E-mail: eomedranos@hotmail.com [Universidade Federal de Sao Carlos (UFSCar), SP (Brazil). Departamento de Engenharia de Materiais; Vilar, R. [Instituto Superior Tecnico, Departamento de Engenharia Quimica, Lisboa (Portugal); Ramasco, B. [Whirlpool Latin America, Rio Claro, SP (Brazil)

    2016-07-01

    A new experimental technique used to analyze the effect of compositional variation and cooling rate in the phase formation in a multicomponent system is the laser cladding. This work have evaluated the use of laser cladding to discover a new bulk metallic glass (BMG) in the Al-Co-Zr system. Coatings with composition variation have made by laser cladding using Al-Co-Zr alloys powders and the samples produced have been characterized by X ray diffraction, microscopy and energy-dispersive X-ray spectroscopy. The results did not show the composition variation as expected, because of incomplete melting during laser process. It was measured a composition variation tendency that allowed the glass forming investigation by the glass formation criterion λ+Δh{sup 1/2}. The results have showed no glass formation in the coating samples, which prove a limited capacity of Zr-Co-Al system to form glass (author)

  5. Y-method for subsea equipment installation; Metodo Y de instalacao de equipamentos 'subsea'

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Melquisedec F.; Neves, Cassiano R. [SUBSIN - Subsea Integrity Engenharia e Projetos Ltda., Rio de Janeiro, RJ (Brazil)

    2008-07-01

    The paper presents a new design of equipment to fall to the seabed, and the results of preliminary calculations to validate the concept. The goals to be achieved consider the current reality of offshore production demands the increasing use of equipment background with large mass and dimensions at increasing depths. The increase of the depths brings necessarily, independent of the mass value, the appearance of a 'zone of resonance' in which pick of tensions arise in values often exceed the capacity of the traction cables designed with all the factors of safety required in standard. This phenomenon necessitates the use of equipment that create the 'spring effect', damping equipment installed in the line of tension involving the use of cranes and ferries or compensating for 'heave' trying to minimize the effects of the balance of the sea in the operation involving where the use of vessels of large size and high cost. By splitting the vector of the load in two, by two different boats, six variables are introduced make it easy to control. The variables are: relative positions and lengths of the cable of witch vessel and the speed of descent of these cables. This development emphasized the cost factor to meet technical and operational characteristics of this type of work, including the same way all the safety requirements and operational speed. As a result of the additional method, we were able to introduce a new parameter in the coupling of equipment in the background since the method also brings the possibility of total control of the speed of approach and touch a tool in its 'slot' even it in a sea adverse. (author)

  6. Comparison of methods for prioritizing risk in radiation oncology; Comparacao entre metodos de priorizacao de riscos em radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Biazoto, Bruna; Tokarski, Marcio, E-mail: bruna@ceb.unicamp.br [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Centro de Engenharia Biomedica

    2016-07-01

    Proactive risk management tools, such as Failure Mode and Effect Analysis (FEMA), were imported from engineering and have been widely used in Radiation Oncology. An important step in this process is the risk prioritization and there are many methods to do that. This paper compares the risk prioritization of computerized planning phase in interstitial implants with high dose rate brachytherapy performed with Health Care Failure Mode and Effect Analysis (HFMEA) and FMEA with guidelines given by the Task Group 100 (TG 100) of the American Association of Physicists in Medicine. Out of the 33 possible failure modes of this process, 21 require more attention when evaluated by HFMEA and 22, when evaluated by FMEA TG 100. Despite the high coincidence between the methods, the execution of HFMEA was simpler. (author)

  7. Diagnostic methods in ischemic necrosis of the femoral head. Metodos de diagnostico en la necrosis isquemica de la cabeza femoral

    Energy Technology Data Exchange (ETDEWEB)

    Parra Blanco, J.A.; Pagola Serrano, M.A.; Delgado Macias, M.T. (Hospital Universitario Marques de Valdecilla, Santander (Spain))

    1994-01-01

    Ischemic necrosis of the femoral head (INFH) must be diagnosed at an early stage of development, when therapeutic approaches such as forage biopsy or osteotomy can prevent or slow the normal progression of the disease to arthrosis. In this article, on the basis of the pathological changes that characterize process, we review the advantages and limitations of the principal diagnostic techniques (table I) currently employed in the study of INFH. (Author)

  8. Influence of the drying method in chitosans purification step; Influencia do metodo de secagem na etapa de purificacao de quitosanas

    Energy Technology Data Exchange (ETDEWEB)

    Fonseca, Ana C.M.; Batista, Jorge G.S.; Bettega, Antonio; Lima, Nelson B. de, E-mail: acmfonseca.acf@gmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    Currently, the study of extracellular biopolymers properties has received prominence for being easy extraction and purification. Chitosan has been an attractive proposition for applications in various fields such as engineering, biotechnology, medicine and pharmacology. For such applications, it is necessary purification of chitosan to obtain a product more concentrated and free of undesirable impurities. However, at this stage of the process of obtaining the biopolymer may occur morphological and physicochemical changes. This study evaluated the influence of the drying process after purification of a commercial chitosan sample and the importance of this step and its cost/benefit in applications requiring a high degree of purity. The method of drying influenced in the organoleptic properties and in the main characteristics of material. Analysis of the crystal structure by X-ray diffraction showed that the degree of crystallinity, X (%), in the purified chitosan samples was lower when compared with the unpurified sample. The degree of acetylation, DA (%), was analyzed by spectroscopy infrared with no significant changes on the three drying methods assessed, unlike the viscosimetric molecular weight, M{sub v}, determined by capillary viscometry. (author)

  9. Chemical analysis of superconductor material by Rietveld method; Analise quimica de material superconductor atraves do metodo de Rietveld

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Junior, E.S.; Gomes Junior, G.G.; Ogasawara, T., E-mail: georges@metalmat.ufrj.b [Universidade Federal do Rio de Janeiro (COPPE/UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-Graduacao de Engenharia. Dept. de Eng. Metalurgica e Materiais; Bispo, E.R.; Polasek, A. [Centro de Pesquisas de Energia Eletrica (CEPEL), Rio de Janeiro, RJ (Brazil); Amorim, H.S. [Universidade Federal do Rio de Janeiro (IF/UFRJ), RJ (Brazil). Inst. de Fisica

    2010-07-01

    Among the main superconducting systems, the system Bi-Sr-Ca-Cu-O is extremely important because it presents two stages of high superconducting critical temperature. To manufacture samples of the superconducting phase (Bi, Pb){sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}Ox (Bi-2223) were used oxides and carbonates of high purity. The mixture was calcined and sintered for 100-200h in air. To characterize the material we used X-ray diffraction, SEM / EDS and measurement of critical temperature (Tc). The Rietveld method was used for structure refinement, and quantification of phases and to estimate the chemical composition of samples in order to obtain greater control of chemical composition using only the data of X-ray diffraction. The results were compared with the refinement results of X-ray fluorescence and was observed a discrepancy of about 8%. This result indicates that the Rietveld method can be an interesting alternative to perform chemical analysis. (author)

  10. Fuel cell design using a new heuristic method; Diseno de celdas de combustible mediante un nuevo metodo heuristico

    Energy Technology Data Exchange (ETDEWEB)

    Perusquia, R.; Montes T, J. L.; Ortiz S, J. J.; Castillo M, A., E-mail: joseluis.montes@inin.gob.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2014-10-15

    In this paper a new method for the pre-design of a typical fuel cell with a structural array of 10 x 10 fuel elements for a BWR is presented. The method is based on principles of maximum dispersion and minimum peaks of local power within the array of fuel elements. The pre-design of the fuel cells is made by simulation in two dimensions (2-D) through the cells physics code CASMO-4. For this purpose of pre-design the search process is guided by an objective function which is a combination of the main neutronic parameters of the fuel cell. The results show that the method is a promising tool that could be used for the design of fuel cells for use in a nuclear plant BWR. (Author)

  11. Evaluation of methods for wax determination in crude oil; Avaliacao de metodos de determinacao de parafinas em petroleo

    Energy Technology Data Exchange (ETDEWEB)

    Dias, Julio Cesar M.; Silva, Maria do Socorro A.J. da; Vasconcellos, Rosa C.U. [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas; Tamanqueira, Juliana B. [Fundacao Gorceix, Ouro Preto, MG (Brazil)

    2008-07-01

    Determining the wax content of crude oil is of great importance for petroleum industry, especially for production, storage and transportation of crude oils. Many different methodologies of wax determining are available in the technical literature. However, the selection of the most suitable method must be in accordance with the aim of the analysis and observing the specificities of each technique. The purpose of this work was to determine the performance of different techniques of wax determining applied to characterization of precipitation properties of waxy compounds in crude oils. Twelve samples of crude oils proceeding from the main Brazilian oil producing sedimentary basins were selected for this study. These samples were analyzed by three important analytical techniques of wax determining: precipitation by cooled solvent; liquid chromatography with precipitation by cooled solvent; and liquid chromatography followed by gas chromatography. Differential scanning calorimetry data related to the wax crystallization in these oils were used as parameters of validation. The results obtained in this study indicate that the liquid chromatography followed by gas chromatography method has the best performance for wax determining in crude oils. (author)

  12. The Brazilian dilution method for ballast water exchange; O metodo de diluicao brasileiro para troca de agua de lastro

    Energy Technology Data Exchange (ETDEWEB)

    Mauro, Celso Alleluia [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas. Avaliacao e Monitoramento Ambiental]. E-mail: celso@cenpes.petrobras.com.br; Land, Claudio Goncalves [PETROBRAS, Rio de Janeiro, RJ (Brazil). Abastecimento, Logistica e Planejamento]. E-mail: cgland@petrobras.com.br; Pimenta, Jose Maria Hollanda Alvares; Barreto, Francisco Carlos Peixoto [PETROBRAS, Rio de Janeiro, RJ (Brazil). Engenharia; Brandao, Marcus Vinicius Lisboa; Marroig, Nilton Lemos [Transpetro, Rio de Janeiro, RJ (Brazil). Frota Nacional de Petroleiros. Inspetoria Geral; Tristao, Maria Luiza Braganca [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas. Quimica; Fadel, Andre Luiz da Fonseca [PETROBRAS, Rio de Janeiro, RJ (Brazil). Financas Corporativa e Tesouraria; Villac, Maria Celia; Fernandes, Lohengrin; Paranhos, Rodolfo; Dias, Cristina; Bonecker, Sergio; Denise Tenenbaum [Universidade Federal, Rio de Janeiro, RJ (Brazil). Inst. de Biologia; Persich, Graziela; Garcia, Virginia; Odebrecht, Clarisse [Fundacao Universidade do Rio Grande, RS (Brazil). Dept. de Oceanografia

    2002-12-01

    In a precautionary approach and dealing with the coming International Maritime Organization (IMO) regulations on ballast water, PETROBRAS developed a new method for ballast water exchange in tankers. Differently from ordinary methods PETROBRAS method which have been called Brazilian Dilution Method (BDM) or Dilution Method involves ballast loading through the top with simultaneous unloading from the bottom of the tanks. The method proposal was firstly presented to IMO, which encouraged PETROBRAS to carry out a field trial. PETROBRAS in June 1998 carried out a trial in the product carrier M/V Lavras. A simulation study was useful to plan the trial assessing the theoretical efficiency of the method, establishing the best sampling points and comparing the BDM with the Tank Overfilling Method (TOM). Simulation showed that for the same tank shape, the water renewal in BDM is more effective than in TOM and that 90 % of water renewal could be obtained by BDM. A dye concentration variation monitoring and a biological assessment were performed and the results confirmed that over than 90 % of the ballast water was renewed after three exchanges. The method was proved safe, practical, economical and suitable to minimize the risk of exotic species transport between ports. (author)

  13. LA INVESTIGACION COMO CONTENIDO, METODO, ENFOQUE Y CONTEXTO EN LA FORMACIÓN DE LOS PROFESIONALES EN LA UNIVERSIDAD CONTEMPORANEA.

    Directory of Open Access Journals (Sweden)

    Alina Martínez

    2016-04-01

    La universidad, tiene un papel fundamental en el proceso respectivo y potencia las competencias de sus educandos, y entre las funciones principales la creacion de cultura a partir de los procesos de investigacion que en ella se genera y, consecuentemente, participa de manera activa en la solucion de los problemas del entorno, lo que tambien constituye su encargo social; siendo este fundamental en el proceso y la prioridad en la formacion para la investigacion de los estudiantes y al desarrollo de habilidades formativas como parte de sus competencias profesionales, ademas de la autopreparacion y cpacitacion permanente del docente vínculo clave en los procesos de desarrollo. La capacidad laboral mediad a través de las competencias, que el educando recibe en su proceso de formacion, es la búsqueda de los elementos necesarios que constituyen habilidades, destrezas, comportamientos debidamente organizados a fin de lograr metas y objetivos concretos, estos deben ser medidos y cualificados con eficacia, dentro de los niveles de rendimiento exigidos en el trabajo; se logra con la adquisicion y desarrollo de conocimientos, expresados en el desempeño a través de la integracion del saber, el saber hacer y saber ser.

  14. Modificação do metodo "kindling" para obtenção de status epilepticus experimental em ratos

    Directory of Open Access Journals (Sweden)

    Carlos J. Reis de Campos

    1980-03-01

    Full Text Available Foi utilizada em nova espécie animal (ratos, uma modificação do método "kindling", introduzida por Taber e col. (1977 para obtenção de status epilepticus experimental. Para isso foram implantados mediante cirurgia estereotáxica, eletrodos duplos, torcidos no hipocampo dorsal de 12 ratos machos albinos. Esses animais foram submetidos, após uma semana de pós-operatório, a 1 segundo de estimulação elétrica de baixa intensidade em forma intermitente, um estímulo por minuto durante 2 horas, desenvolvendo-se em prazo de 30 minutos um estado de epilepsia eletrográfica e comportamental duradoura. Vários padrões de descargas epilépticas eletrográficas foram observados bem como manifestações convulsivas tônico-clônicas. Os animais que foram submetidos a novas sessões de estimulação após 7 e 14 dias mostraram aumento de atividade epiléptica demonstrando uma modificação plástica do hipocampo do rato submetido a estimulação elétrica a qual perdura no tempo. O método permite a obtenção de "kindling" em tempo bem mais curto (horas, comparativamente às técnicas anteriormente descritas (dias, tornando-se um promissor modelo de epilepsia para testes de drogas anticonvulsivantes e para o estudo dos mecanismos fisiopatológicos e bioquímicos envolvidos na descarga epiléptica.

  15. A definitive method for dosimetry with radiochromic movie; Un metodo definitivo para la dosimetria con pelicula radiocromica

    Energy Technology Data Exchange (ETDEWEB)

    Miras del Rio, H.; Arrans Lara, R.

    2013-07-01

    Despite the undoubted benefits of radiochromic film as a two-dimensional radiation detector, the manufacturing process and characteristics of scanners make to present some inherent difficulties that result that its use is complex, tedious, and if not performed so appropriate, imprecise. A protocol that simplifies the calibration process while reducing the number of films used for this purpose is proposed systematically corrects several difficulties, both inherent in the manufacture of the film as the reader and, what is more important achieves levels comparable to those of other more widespread use detectors accuracy. (Author)

  16. Intussusception in children: imaging evaluation and therapeutic approach; Intussuscepcao em criancas: avaliacao por metodos de imagem e abordagem terapeutica

    Energy Technology Data Exchange (ETDEWEB)

    Cunha, Fabio Motta da; Figueiredo, Sizenildo da Silva; Nobrega, Bruno Barcelos da; Monteiro, Soraya Silveira; Lederman, Henrique Manoel [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil). Dept. de Diagnostico por Imagem]. E-mail: brunoradiol@hotmail.com; Oliveira, Galba Leite [Irmandade Santa Casa de Misericordia de Sao Paulo, SP (Brazil). Dept. de Diagnostico por Imagem

    2005-05-15

    Intussusception is a medical emergency that occur with higher frequency in children under 2 years of age. Diagnosis can be difficult as the classical triad of abdominal pain, jelly stools and palpable abdominal mass is seen in less than 50% of the patients. However, the diagnosis of intussusception can be established with variable degree of accuracy using plain abdominal x-ray films, ultrasound, computed tomography or barium (or air/saline) enema. Some of these imaging methods are also useful during treatment of this condition. The authors present a review of the literature and a pictorial essay of the imaging findings in patients with intussusception. In addition, a discussion on the current and controversial issues related to the treatment of intussusception is presented. (author)

  17. Precise magnetostatic field using the finite element method; Calculo de campos magnetostaticos com precisao utilizando o metodo dos elementos finitos

    Energy Technology Data Exchange (ETDEWEB)

    Nascimento, Francisco Rogerio Teixeira do

    2013-07-01

    The main objective of this work is to simulate electromagnetic fields using the Finite Element Method. Even in the easiest case of electrostatic and magnetostatic numerical simulation some problems appear when the nodal finite element is used. It is difficult to model vector fields with scalar functions mainly in non-homogeneous materials. With the aim to solve these problems two types of techniques are tried: the adaptive remeshing using nodal elements and the edge finite element that ensure the continuity of tangential components. Some numerical analysis of simple electromagnetic problems with homogeneous and non-homogeneous materials are performed using first, the adaptive remeshing based in various error indicators and second, the numerical solution of waveguides using edge finite element. (author)

  18. Determination of polycyclic aromatic hydrocarbons (PAHs). gas chromatographic method; Determinazione degli idrocarburi policiclici aromatici (IPA). Metodo gascaromatografico

    Energy Technology Data Exchange (ETDEWEB)

    Menichini, E; Viviano, G [Istituto Superiore di Sanita` , Rome (Italy). Lab. di Igiene Ambientale

    1997-12-01

    The method enables the determination of 4- to 6- ring PAHs and particularly of carcinogenic PAHs regulated in Italy. This revision is based on the results of a national collaborative study. Sample extract, obtained by a method described in a previous report (Rapporto ISTISAN: 90/33) is cleaned up by thin layer chromatography and analysed by gas chromatography; identification is confirmed by mass spectrometry. An intralaboratory quality control program is described.

  19. Thermochemical methods for the treatment of oil contaminated sand; Metodo termoquimico para tratamento de areia contaminada por oleo

    Energy Technology Data Exchange (ETDEWEB)

    Pimenta, Rosana C.G.M. [Fundacao Jose Bonifacio, Rio de Janeiro, RJ (Brazil); Khalil, Carlos N. [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)

    2003-07-01

    The Nitrogen Generating System (SGN in Portuguese) is a thermochemical method first developed for cleaning and removal of paraffin deposits in production and export pipelines. SGN is based on a redox chemical reaction between two salts which is catalyzed in acidic pH. The reaction is strongly exothermic and its products are nitrogen, sodium chloride, water and heat. All reaction products are harmless to the environment. In January 2000 there was a major oil spill in Guanabara Bay, Rio de Janeiro, which contaminated 2400 tons of sand. This work, developed at PETROBRAS Research Center (CENPES), was based on SGN technology which has been adapted for cleaning contaminated sand and recovering of spilled oil. By combining simultaneous effects of the SGN treatment such as heating, turbulence and floatation, one can remove, within 98% of efficiency, spilling oil from contaminated sand and removed oil can be securely returned to refining process. SGN technology has proved to be efficient, fast, low cost and ecologically correct method for cleaning contaminated sand and can be applied in loco right after a contamination event. (author)

  20. Thermochemical method for the treatment of oil contaminated sand; Metodo termoquimico para tratamento de areia contaminada por oleo

    Energy Technology Data Exchange (ETDEWEB)

    Pimenta, Rosana C.G.M. [Fundacao Gorceix, Ouro Preto, MG (Brazil)]|[PETROBRAS S.A., Rio de Janeiro, RJ (Brazil); Khalil, Carlos N. [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)

    2004-07-01

    In January 2000 there was a major oil spill in Guanabara Bay, Rio de Janeiro, which contaminated 2400 tons of sand. This work, based on NGS (Nitrogen Generating System) technology, was adapted for cleaning contaminated sand and recovering of spilled oil. NGS is a thermochemical method first developed for removal of paraffin deposits in production and export pipelines. The method is based on a strongly exothermic redox chemical reaction between two salts catalyzed in acidic pH. The reaction products are harmless to the environment and consist of nitrogen, sodium chloride, water and heat. By combining simultaneous effects of the treatment such as heating, turbulence and floatation, one can remove, within 98% of efficiency, spilling oil from contaminated sand. After treatment, removed oil can be securely returned to refining process. The method has proved to be efficient, fast, low cost and ecologically correct method for cleaning contaminated sand and can be applied in place right after a contamination event. (author)

  1. Eficacia do metodo Meir Schneider de autocuidado em pessoas com distrofias musculares progressivas : ensaio clinico fase II

    OpenAIRE

    Lea Beatriz Teixeira Soares

    1999-01-01

    Resumo: As pessoas com distrofias musculares progressivas vivem o limite do conhecimento médico e aguardam resultados de pesquisa da prevenção, reabilitação e mesmo a cura dos indivíduos portadores. Nesse contexto discute-se a eficácia do método Meir Schneider de autocuidado (self-healing) baseado em ensaio clínico fase II em 12 pessoas com distrofias musculares progressivas, sob tratamento ambulatorial intensivo e não intensivo. Foram atendidos 7 portadores de Distrofia Muscular Duchenne- DM...

  2. A method multi criterio to evaluate projects of rural electrification; Un metodo multicriterio para evaluar proyectos de electrificacion rural

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez Posse, E

    1994-07-01

    In this document about the problem of the evaluation projects methodologies in rural electrification.The low analysis problem is of complex nature, because each project is evaluation object and an economic agent. One of these agents identifies different benefits and cost, and also has a different approaches for value them.In consequence, the form in that it is carried out the evaluation of the one project for each one of this agents that it is usually solved for mechanisms linked to the capacity of incidence or of determination of each one of them, this does not assures a satisfactory results for the general interest.

  3. Rigid inclusions-Comparison between analytical and numerical methods; Inclusiones rigidas-Analisis comparativo de los metodos analiticos y numericos

    Energy Technology Data Exchange (ETDEWEB)

    Gomez Perez, R.; Melentijevic, S.

    2014-07-01

    This paper compares different analytical methods for analysis of rigid inclusions with finite element modeling. First of all, the load transfer in the distribution layer is analyzed for its different thicknesses and different inclusion grids to define the range between results obtained by analytical and numerical methods. The interaction between the soft soil and the inclusion in the estimation of settlements is studied as well. Considering different stiffness of the soft soil, settlements obtained analytical and numerically are compared. The influence of the soft soil modulus of elasticity on the neutral point depth was also performed by finite elements. This depth has a great importance for the definition of the total length of rigid inclusion. (Author)

  4. Preparation methods, reactivity and biological importance of 4-thiazolidinones; Metodos de obtencao, reatividade e importancia biologica de 4-tiazolidinonas

    Energy Technology Data Exchange (ETDEWEB)

    Liesen, Andre P.; Aquino, Thiago M. de; Goes, Alexandre J.S. [Universidade Federal de Pernambuco (UFPE)e, PE (Brazil). Dept. de Antibioticos]. E-mail: ajsg@ufpe.br; Lima, Jose G. de; Faria, Antonio R. de; Alves, Antonio J. [Universidade Federal de Pernambuco (UFPE)e, PE (Brazil). Dept. de Ciencias Farmaceuticas

    2008-07-01

    Molecules containing the 4-thiazolidinone ring are known to possess a wide range of biological properties including antimicrobial and antiinflammatory activities among others. These compounds can be synthesized by cyclization reactions involving alpha-haloacetic acid or alpha-mercaptoacetic acid and employed in several chemoselective reactions. Comprehensive reviews have been written on 4-thiazolidinones in 1961 by Brown and in 1980 by Singh et al. In the recent literature, some new synthesis methods for 4-thiazolidinone derivatives and several reactions have been reported. These advances warrant to review the chemical and biological properties of compounds with this important heterocycle employed in synthetic organic chemistry and medicinal chemistry (author)

  5. Thiosemicarbazones: preparation methods, synthetic applications and biological importance; Tiossemicarbazonas: metodos de obtencao, aplicacoes sinteticas e importancia biologica

    Energy Technology Data Exchange (ETDEWEB)

    Tenorio, Romulo P.; Goes, Alexandre J.S. [Universidade Federal de Pernambuco, Recife, PE (Brazil). Dept. de Antibioticos]. E-mail: ajsg@ufpe.br; Lima, Jose G. de; Faria, Antonio R. de; Alves, Antonio J.; Aquino, Thiago M. de [Universidade Federal de Pernambuco, Recife, PE (Brazil). Dept. de Ciencias Farmaceuticas

    2005-11-15

    Thiosemicarbazones are a class of compounds known by their chemical and biological properties, such as antitumor, antibacterial, antiviral and antiprotozoal activity. Their ability to form chelates with metals has great importance in their biological activities. Their synthesis is very simple, versatile and clean, usually giving high yields. They are largely employed as intermediates, in the synthesis of others compounds. This article is a survey of some of these characteristics showing their great importance to organic and medicinal chemistry. (author)

  6. Determination of power distribution in reactor with nodal expansion method; Izrachun porazdelitve mochi v reaktorju z metodo nodalne ekspanzije

    Energy Technology Data Exchange (ETDEWEB)

    Kromar, M; Trkov, A [Institut Jozef Stefan, Ljubljana (Yugoslavia); Pregl, G [Tehnishka Fakulteta Maribor Univ. (Yugoslavia)

    1988-07-01

    Nodal expansion method (NEM) is one of the advanced coarse-mesh methods based on integral form of few-group diffusion equation. NEM can be characterized by high accuracy and computational efficiency. Method was tested by development of computer code NEXT. Validation of the code was performed by calculation of 2-D and 3-D IAEA benchmark problem. NEXT was compared with codes based on other methods (finite differences, finite elements) and has been found to be accurate as well as fast. (author)

  7. A new method for dosimetry with films radiochromic; Un nuevo metodo para la dosimetria con peliculas radiocromica

    Energy Technology Data Exchange (ETDEWEB)

    Mendez Carot, I.

    2013-07-01

    in this paper a new method is presented and the results of the comparison between the calibration is summarized based on a planning reference and calibration obtained from the irradiated fragments measure different dose levels multichannel compare dosimetry based on the weighted average dosimetry described by Micke et al.(present in the FilmQAPro software) and, finally, show different results obtained with the method proposed in several applications clinics. (Author)

  8. Pipeline integrity management using Monte Carlo simulation; A aplicacao do metodo de Monte Carlo no gerenciamento da integridade de dutos

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, Claudio; Costa, Artur; Bittencourt, Euclides [TRANSPETRO - PETROBRAS Transporte, Rio de Janeiro, RJ (Brazil)

    2005-07-01

    Due to the growing relevance of safety and environmental protection policies in PETROBRAS and its subsidiaries, as well as official regulatory agencies and population requirements, integrity management of oil and gas pipelines became a priority activity in TRANSPETRO, involving several sectors of the company's Support Management Department. Inspection activities using intelligent PIGs, field correlations and replacement of pipeline segments are known as high cost operations and request complex logistics. Thus, it is imperative the adoption of management tools that optimize the available resources. This study presents Monte Carlo simulation method as an additional tool for evaluation and management of pipeline structural integrity. The method consists in foreseeing future physical conditions of most significant defects found in intelligent PIG In Line Inspections based on a probabilistic approach. Through Monte Carlo simulation, probability functions of failure for each defect are produced, helping managers to decide which repairs should be executed in order to reach the desired or accepted risk level. The case that illustrates this study refers to the reconditioning of ORSOL 14'' (35,56 mm) pipeline. This pipeline was constructed to transfer petroleum from Urucu's production fields to Solimoes port, in Coari, city in Brazilian Amazon Region. The result of this analysis indicated critical points for repair, in addition to the results obtained by the conventional evaluation (deterministic ASME B-31G method). Due to the difficulties to mobilize staff and execute necessary repairs in remote areas like Amazon forest, the probabilistic tool was extremely useful, improving pipeline integrity level and avoiding future additional costs. (author)

  9. The Possibility of Making a Quantitative Study of the Precipitin Reaction by Gamma-Radioactive Tracers; Possibilite d'une Etude Quantitative de la Reaction de Precipitation par Marquage a l'Aide d'Emetteurs Gamma; Vozmozhnost' kolichestvennogo opredeleniya reaktsii osazhdeniya s pomoshch'yu gamma-radioaktivnykh indikatorov; Estudio Cuantitativo de la Reaccion de Precipitacion con Ayuda de Indicadores Gamma

    Energy Technology Data Exchange (ETDEWEB)

    Bonev, L.; Todorov, S.; Robev, S. [Nauchno-Issledovatel' skij Institut Radiologii i Radiacionnoj Bezopasnosti, Sofija (Bulgaria)

    1965-10-15

    indicadores gamma que no reaccionan quimicamente con las moleculas de albumina. Como indicadores pueden utilizarse ciertos compuestos de cromo, manganeso y hierro que, por su teridencia a hidrolizarse, permiten fijar el indicador radiactivo en el antigeno y en el anticuerpo, respectivamente. La radiactividad de los componentes se determino con ayuda de un analizador multicanal de amplitud de impulsos. Los resultados obtenidos demuestran que la curva de precipitacion, trazada sobre la base de los datos radiometricos, concuerda con la que se obtiene por los metodos cuantitativos corrientemente empleados en la valoracion de la albumiRa. Los autores examinan las posibilidades de aplicacion del metodo descrito. (author) [Russian] Soobshhajutsja pervye rezul'taty kolichestvennogo opredelenija reakcii osazhdenija (obrazovanija kompleksa antigen-antitelo) posredstvom mechenija precipitacionnyh komponentov gamma-radioaktivnymi indikatorami, ne vstupajushhimi v himicheskoe vzaimodejstvie s belkovymi molekulami. V kachestve indikatorov mogut byt' ispol'zovany hromomargancevye soedinenija i soedinenija zheleza, sklonnost' kotoryh k gidrolizu obespechivaet fiksaciju radioaktivnogo indikatora na antigene sootvetstvenno i na antitelo. Opredelenie radioaktivnosti komponentov proizvoditsja posredstvom mnogokanal'nogo amplitudnogo analizatora. Poluchennye rezul'taty pokazyvajut, chto precipitacionnaja krivaja, postroennaja na osnovanii radiometrichnyh dannyh, nahoditsja v blizkom sootvetstvii s krivoj, postroennoj izvestnymi kolichestvennymi metodami, sluzhashhimi dlja opredelenija belka. Rassmatrivajutsja vozmozhnosti primenenija jetogo metoda na praktike. (author)

  10. Use of microcontroller in gamma-ray spectrometer construction using NaI(Tl) sensor, with emphasis in multichannel analyzer, to applications in nuclear and environmental geophysics; Uso de microcontrolador na construcao de espectrometro gama com sensor de NaI(Tl), com enfase em analisador multicanal, para aplicacao em geofisica nuclear e ambiental

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Nilton

    2005-07-01

    In this work of nuclear geophysical instrumentation the main purpose was the development of a gamma-ray spectrometer prototype with multi channel analyzer, since the spectroscopic amplifier until your firmware. The heart of the digital part was an ATMEL 8 bits microcontroller (AT89S8252). All circuits were made and assembled in the Laboratory of Applied Geophysical Instrumentation (LIGA) of IAG-USP. A microcontroller software was completely developed in C ANSI language using the Small Device C Compiler version 2.4.8, that is a free software distributed under General Public License (GPL). At first, microcontroller was used to change all digital circuit of one classic SCINTREX GAD-6 differential gamma-ray spectrometer. Measurement times with order of 2 days became possible, and it could work in non climate ambient. Then, after this stage, had been started the development of a multichannel analyzer (MCA) working in pulse height analyzer mode with 4096 channels capacity, to use in many kinds of nuclear detection. Besides it, was developed an automatic gain system for photopeak stabilization, by the use of one radioactive source ({sup 133}Ba). This automatic gain system is very important in the case of NaI(Tl) scintillometric detectors, due PMT sensitivity with temperature and aging of some laboratory electronic circuits. Two power supplies with high stability, using pulse width modulation (PWM) techniques were developed, in order to all system became free of electrical line break off. One PWM power polarizes a photo multiplier tube (PMT) with high voltage and another supplies remaining developed circuits. Calibration in energy using standards sources {sup 137}Cs and {sup 60}Co showed that gamma detector developed has a good linearity and low thermal drift, even working in absent of air-conditioned. Concentrations measurements of K, U and Th were made in samples of soils, vegetables, etc. (author)'

  11. Determination of the Antarctic region active margin basement by using integration of the information coming from the multichannel seismic analysis and the magnetometry; Determinacao do embasamento da margen ativa da regiao Antartica pela integracao de informacoes provenientes da sismica multicanal e da magnetometria

    Energy Technology Data Exchange (ETDEWEB)

    Torres, Luiz Carlos [Diretoria de Hidrografia e Navegacao, XX (Brazil); Gomes, Benedito Souza [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil); Gamboa, Luiz Antonio P. [Universidade Federal Fluminense, Niteroi, RJ (Brazil)

    1999-07-01

    Geophysical measurements were carried out in the Western Margin of the Antarctic Peninsula and Bransfield Strait by the Brazilian Antarctic Program during the summers of 1987 and 1988. The present work, using a continued seismic multi channel and magnetometry data profile crossing the area, intends to present a two-dimensional model of the interface sediment/basement and contribute to the understanding of the complex geology verified in the studying area. By this model, the main provinces of the are (Deep Ocean, South Shetland Trench, Accretionary Prism, Volcanic Arc South Shetland Islands and Bransfield Basin) could be determined. The seismic and magnetic measurements information when superposed can attribute more consistencies to the interpreted basement; although each method has its particular resolution. This way, when the seismic interpretation was not possible due to complex structures disposition, magnetic measurements could offer good estimation about basement depth. The fit between both methods (seismic and magnetic measurements) was reasonable both on the oceanic basin and in the region of Bransfield Strait. The magnetometry, as as well seismic, was sensible to the dip of Drake Plate at South Shetland Trench and the Intrusive occurrence at Bransfield Basin axis. (author)

  12. Calibration of UFBC counters and their performance in the assay of large mass plutonium samples

    International Nuclear Information System (INIS)

    Verrecchia, G.P.D.; Smith, B.G.R.; Cranston, R.

    1991-01-01

    This paper reports on the cross-calibration of four Universal Fast Breeder reactor assembly coincidence (UFBC) counters using multi-can containers of Plutonium oxide powders with masses between 2 and 12 Kg of plutonium and a parametric study on the sensitivity of the detector response to the positioning or removal and substitution of the material with empty cans. The paper also reports on the performance of the UFBC for routine measurements on large mass, multi-can containers of plutonium oxide powders and compares the results to experience previously obtained in the measurement of fast reactor type fuel assemblies in the mass range 2 to 16 Kg of plutonium

  13. Development of computer programme for the use of empirical calculation of mining subsidence; Desarrollo informatico para utilizacion de los metodos empiricos de calculo de subsidencia minera

    Energy Technology Data Exchange (ETDEWEB)

    1999-09-01

    The fundamental objective of the project is the elaboration of a user friendly computer programme which allows to mining technicians an easy application of the empirical calculation methods of mining subsidence. As is well known these methods use, together with a suitable theoretical support, the experimental data obtained during a long period of mining activities in areas of different geological and geomechanical nature. Thus they can incorporate to the calculus the local parameters that hardly could be taken into account by using pure theoretical methods. In general, as basic calculation method, it has been followed the procedure development by the VNIMI Institute of Leningrad, a particularly suitable method for application to the most various conditions that may occur in the mining of flat or steep seams. The computer programme has been worked out on the basis of MicroStation System (5.0 version) of INTERGRAPH which allows the development of new applications related to the basic aims of the project. An important feature, of the programme that may be quoted is the easy adaptation to local conditions by adjustment of the geomechanical or mining parameters according to the values obtained from the own working experience. (Author)

  14. Analytical methods for 2,4-D (Dichlorophenoxyacetic acid) determination; Metodos analiticos para la determinacion del 2,4-D (Acido diclorofenoxiacetico)

    Energy Technology Data Exchange (ETDEWEB)

    Martinez G, M.S.M

    1999-06-01

    The 2,4-D herbicide is one of the main pesticides for controlling the bad grass in crops such as the water undergrowth. In Mexico the allowed bound of this pesticide is 0.05 mg/l in water of 2,4-D so it is required to have methods trusts and exacts, which can used in order to detected low concentration of it. In this work we show some for the conventional techniques and for establishing the 2,4-D concentrations. The UV-Vis spectrometer and liquids chromatography due that they are the most common used nowadays. Beside, we introduce a now developed technique, which is based on the neutronic activation analysis. Though use of the UV-Vis spectrometer technique it was possible target the concentrations interval between 1 and 200 mg/l. In the liquids chromatography interval was between 0.1 and 0.9, and by the neutronic activation analysis the interval was between 0.01 and 200 mg/l. (Author)

  15. An Optimised Method to Determine PAHs in a Contaminated Soil; Metodo Optimizado para la Determinacion de PAHs en un Suelo Contaminado

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Alonso, S.; Perez Pastor, R. M.; Sevillano castano, M. L.; Escolano Segovia, O.; Garcia Frutos, F. J.

    2007-07-20

    An analytical study is presented based on an optimised method to determine selected polycyclic aromatic hydrocarbons (PAHs) by High Performance Liquid Chromatography (HPLC) with fluorescence detection. The work was focused to obtain reliable measurements of PAH in a gas work contaminated soil and was performed in the frame of the project 'Assessment of natural remediation technologies for PAHs in contaminated soils' (Spanish Plan Nacional l+D+i, CTM 2004-05832-CO2-01): First assays were focused to evaluate an initial proposed procedure by sonication extraction in the contaminated soil. Afterwards to extend the efficiency and reduce solvent and time consuming of extraction procedures, the more relevant parameters that affect the extraction step were investigated. A comparison between sonication and microwave procedures was done, and the influence of sample grinding was studied. In general, both extraction techniques led on comparable results, although sonication procedure needs to be more carefully optimised. Finally, as a final application of the optimised method, the effect of particle size on relative distribution of selected PAHs in the contaminated soil was investigated. Relative abundance of more volatile PAHs showed a decreasing according to lower grain size, while relative abundance of less volatile compounds indicated an increasing of concentration levels for lower grain size. (Author) 10 refs.

  16. Metodo integrado para la gestion de Universidades basado en el Balanced Scorecard (bsc y el modelo europeo de calidad (efqm: caso U.C.S.M.

    Directory of Open Access Journals (Sweden)

    Edwing Jesús Ticse Villanueva

    2010-06-01

    Full Text Available http://dx.doi.org/10.5007/1983-4535.2010v3n1p01   El presente Trabajo realiza la propuesta de un Método Integrado  que permite mejorar la competitividad en la Gestión de las Universidades, este método se basa: En una herramienta de Gestión Estratégica: el Balanced Scorecard (BSC, que fue creada por Kaplan y Norton en 1992; y En el Modelo  Europeo de Calidad (EFQM, que fue desarrollado como un Modelo de Excelencia en 1991. La metodología utilizada consiste en analizar las características, ventajas y limitaciones del BSC y el EFQM para aplicarlos simultáneamente en la gestión de Tomando como base los 9 criterios del EFQM, se desarrolla un Mapa Estratégico del BSC, para que se alineen todas las perspectivas hacia el logro de los Objetivos Estratégicos de la Organización. El método integrado planteado se aplica en el caso de la Universidad Católica de Santa María (Arequipa- Perú, donde se analiza las ventajas que implicaría la implementación del mismo

  17. Applied methods for mitigation of damage by stress corrosion in BWR type reactors; Metodos aplicados para la mitigacion del dano por corrosion bajo esfuerzo en reactores BWR

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez C, R.; Diaz S, A.; Gachuz M, M.; Arganis J, C. [Instituto Nacional de Investigaciones Nucleares, Gerencia de Ciencia de Materiales, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1998-07-01

    The Boiling Water nuclear Reactors (BWR) have presented stress corrosion problems, mainly in components and pipes of the primary system, provoking negative impacts in the performance of energy generator plants, as well as the increasing in the radiation exposure to personnel involucred. This problem has caused development of research programs, which are guided to find solution alternatives for the phenomena control. Among results of greater relevance the control for the reactor water chemistry stands out particularly in the impurities concentration and oxidation of radiolysis products; as well as the supervision in the materials selection and the stresses levels reduction. The present work presents the methods which can be applied to diminish the problems of stress corrosion in BWR reactors. (Author)

  18. Identification of gamma irradiated apples by the half-embryo test; Identificacion de manzanas irradiadas con rayo {gamma} utilizando el metodo del medio embrion

    Energy Technology Data Exchange (ETDEWEB)

    Miranda, Gabriel C; Bujan, Alfonso; Leiva, Carlos H; Yusef, Maria V [Comision Nacional de Energia Atomica, Ezeiza (Argentina). Centro Atomico Ezeiza

    2003-07-01

    The half-embryo test was applied to irradiated apples (var. Red delicious).The irradiation of apples caused obvious changes in the growth of the half-embryo. A dose of 100 Gy or more, inhibits the epicotyl development and with 50 Gy dose is possible to observe a great contrast with the non-irradiated apples. If the epicotyl development is less than 4 cm., the apples are identified as irradiated. The assessment can be made after 7 days. (author)

  19. The irradiation as a quarantine method for the treatment of fresh fruits; La irradiacion como metodo cuarentenario eficaz para el tratamiento de frutas frescas

    Energy Technology Data Exchange (ETDEWEB)

    Kaupert, Norma L [Comision Nacional de Energia Atomica, Ezeiza (Argentina). Dept. de Aplicaciones Tecnologicas y Agropecuarias

    1999-07-01

    The irradiation is proposed as an alternative to chemical or other physical methods for the quarantine of fresh fruit. The case of the products of the Southern part of Argentina is analysed and the economical and financial parameters for the installation and the operation of an irradiation plant are estimated. The costs are compared to those of a chemical quarantine system. (author)

  20. Aplicação do conceito do metodo da linha de balanço no planejamento de obras repetitivas

    OpenAIRE

    Maziero, Lucia Teresinha Peixe

    1990-01-01

    Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnologico O Método da Linha de Balanço é utilizado no planejamento, programação e controle de obras repetitivas. A presente dissertação visa propor uma metodologia de aplicação do Método da Linha de Balanço que fornece melhorias no planejamento e realização da obra. Esta metodologia é desenvolvida através da determinação das principais variáveis de estudo. Observa-se a variação dos recursos necessários à execução da ...

  1. Empleo de metodos numericos para el ajuste de los coeficientes de difusividad (D) y convectivo de transferencia de masa (hm) en el secado de alimentos

    OpenAIRE

    Arranz Saiz, Francisco Javier; Correa Hernando, Eva Cristina; Jiménez Ariza, Heidi Tatiana; Diezma Iglesias, Belen; Garcia-Herrero, Javier; Robla Villalba, José Ignacio; Barreiro Elorza, Pilar

    2011-01-01

    Los modelos matemáticos de transferencia de humedad desde el alimento al medio circundante durante el proceso de secado dependen de dos parámetros: coeficiente de difusividad efectiva D y coeficiente convectivo de transferencia de masa hm, cuya determinación experimental se basa en la consideración de un sistema difusivo sencillo de solución analítica bien conocida. Para el caso, que aquí nos ocupa, de difusión monodimensional en una lámina infinita de grosor 2l, la solución analítica de ...

  2. Upheaval buckling of heated pipelines: a comparative study of three analytical methods; Flambagem vertical de dutos aquecidos: um estudo comparativo de tres metodos analiticos

    Energy Technology Data Exchange (ETDEWEB)

    Cunha, Divino J.S.; Benjamin, Adilson C. [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas

    2005-07-01

    Three analytical methods frequently used for analyzing upheaval buckling are presented and compared in this work: the Hobbs' method which is applied to straight pipelines, the Pedersen-Jensen's method and the JIP-Shell's method, both applied to pipelines containing initial imperfections. The basic equations of the three methods are outlined and its differences are appointed. Also it is studied the sensitivity of the response of the last two methods to the cover of soil and to the amplitude of the initial imperfection. (author)

  3. Trace element determination study in human hair by neutron activation analysis; Estudo da determinacao de elementos traco em cabelos humanos pelo metodo de analise por ativacao com neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Frazao, Selma Violato

    2008-07-01

    Human hair analysis studies have been subject of continuous interest due to the fact that they can be used as an important tool to evaluate trace element levels in the human body. These determinations have been carried out to use hair for environmental and occupational monitoring, to identify intoxication or poisoning by toxic metals, to assess nutritional status, to diagnose and to prevent diseases and in forensic sciences. Although hair analysis presents several advantages over other human tissue or fluid analyses, such as organ tissue, blood, urine and saliva, there are some controversies regarding the use of hair analysis data. These controversies arise from the fact that it is difficult to establish reliable reference values for trace elements in hair. The purpose of this study was to evaluate the factors that affect element concentrations in hair samples from a population considered healthy and residing in the Sao Paulo metropolitan area. The collected human head hair was cut in small pieces, washed, dried and analyzed by neutron activation analysis (NAA). Aliquots of hair samples and synthetic elemental standards were irradiated at the IEA-R1 nuclear research reactor for 16 h under a thermal neutron flux of about 5x10{sup 12} n cm{sup -2} s{sup -1} for As, Br, Ca, Co, Cr, Cs, Cu, Fe, K, La, Na, Sb, Sc, Se and Zn determinations. The induced gamma activities of the standards and samples were measured using a gamma ray spectrometer coupled to an hiperpure Ge detector. For quality control of the results, IAEA- 85 Human Hair and INCT-TL-1 Tea Leaves certified reference materials (CRMs) were analyzed. Results obtained in these CRMs presented for most of elements, good agreement with the values of the certificates (relative errors less than 10%) and good precision (variation coefficients less than 13.6%). Results of replicate hair sample analysis showed good reproducibility indicating homogeneity of the prepared sample. Results obtained in the analyses of dyed and non-dyed hair showed that element adsorption or desorption occurs due to the dye. Analysis of hair samples collected from different regions of the head presented significant differences for the elements Fe, Sc, Se and Cr, indicating the importance of defining head regions for hair sample collection. Results of hair analysis from individuals residing in Sao Paulo metropolitan area showed individual differences for age, gender and natural hair color. Results obtained in this population also showed, that the mean element concentrations found are within the literature values. (author)

  4. Research into methods of dust prevention on mechanised faces. Proyecto de investigacion de metodos de prevencion de polvo en talleres mecanizados

    Energy Technology Data Exchange (ETDEWEB)

    1990-12-01

    In collaboration with the National Institute of Silicosis and AITEMIN, HUNOSA has just completed the first part of a research project on methods of dust prevention on mechanised thin seam faces. Results have been good. The project was largely financed by the EEC in addition to receiving assistance from Ocicarbon and the Directorate General for Mines. 1 fig.

  5. Density evaluation by computerized tomography in plain soils over different manipulation systems; Avaliacao da densidade pelo metodo da tomografia computadorizada de um planossolo sob diferentes sistemas de manejo

    Energy Technology Data Exchange (ETDEWEB)

    Pedrotti, Alceu [Lavras Univ., MG (Brazil). Dept. de Ciencia do Solo; Pauletto, Eloy Antonio [Pelotas Univ., RS (Brazil). Dept. de Solos; Crestana, Silvio [Empresa Brasileira de Pesquisa Agropecuaria (EMBRAPA), Sao Carlos, SP (Brazil). Centro Nacional de Pesquisa e Desenvolvimento de Instrumentacao Agropecuaria (CNPDIA)

    1996-08-01

    The objective of this paper is the evaluation of a plain soil density in different culture systems determined by X ray computerized tomography.It was observed a larger variation in densities in soils profiles analysed. The identification of layers is better utilising computerized tomography than others technic 1 fig.

  6. In-situ gamma spectrometry method for determination of environmental gamma dose; Metodo de espectrometria gamma in situ para determinacao de dose gama ambiental

    Energy Technology Data Exchange (ETDEWEB)

    Conti, Claudio de Carvalho

    1995-07-15

    This work tries to establish a methodology for germanium detectors calibration, normally used for in situ gamma ray spectrometry, for determining the environmental exposure rate in function of the energy of the incident photons. For this purpose a computer code has been developed, based on the stripping method, for the computational spectra analysis to calculate the contribution of the partial absorption of the gamma rays (Compton effect) in the active and nonactive parts of the detector. The resulting total absorption spectrum is then converted to fluence distribution in function of the energy for the photons reaching the detector, which is then used to calculate the exposure rate or kerma in air. The unfolding and fluency convention parameters are determined by detector calibration using point gamma sources. The method is validated by comparison of the results against the calculated exposure rate at a point of interest for the standards. This method is used for the direct measurement of the exposure rate distribution in function of the energy at the site, in situ measurement technic, leading to rapid results during an emergency situation and also used for indoor measurements. (author)

  7. Observability in electric power networks: identification critical measures methods; Observabilidade em redes de energia eletrica: metodos de identificacao de medidas criticas

    Energy Technology Data Exchange (ETDEWEB)

    London Junior, Joao Bosco Augusto

    1997-07-01

    One of the most important functions of the control and operation centers is to maintain service reliability in a electrical power system. In order to obtain a reliable operation of the power system, it is important to identify the critical measurements, and then to improve the measurement system using pseudo measurements. The goal of this work is to determine more efficient methods for critical measurement identification. A brief review of the some methods for observability analysis as well as two methodologies to identify critical measurements are presented. The first method has a combinatorial nature; the second one is supported by uni modular M matrix (incidence matrix of measurements for branches) and A matrix (incidence matrix of branch for nodes). The second method needs a combinatorial algorithm to be feasible, so that it becomes a slow method. Two new methods for critical measurements identification are presented in this work: the first one is based on the theory developed by Bretas (1996a), to analyse observability using graph paths; the second methods is supported y the Slutsker and Scudder (1987) theory, where identification is reached throughout the analysis of the jacobian matrix. (author)

  8. Analysis of medicinal plant extracts by neutron activation method; Analise de extratos de plantas medicinais pelo metodo de ativacao com neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Vaz, Sandra Muntz

    1996-12-31

    This dissertation has presented the results from analysis of medicinal plant extracts using neutron activation method. Instrumental neutron activation analysis was applied to the determination of the elements Al, Br, Ca, Ce, Cl, Cr, Cs, Fe, K, La, Mg, Mn, Na, Rb, Sb, Sc and Zn in medicinal extracts obtained from Achyrolcline satureoides DC, Casearia sylvestris, Centella asiatica, Citrus aurantium L., Solano lycocarpum, Solidago microglossa, Stryphnondedron barbatiman and Zingiber officinale R. plants. The elements Hg and Se were determined using radiochemical separation by means of retention of Se in HMD inorganic exchanger and solvent extraction of Hg by bismuth diethyl-dithiocarbamate solution. Precision and accuracy of the results have been evaluated by analysing reference materials. The therapeutic action of some elements found in plant extracts analyzed was briefly discussed 70 refs., 13 figs., 15 tabs

  9. Analytical Comparison of Miniaturized Methods for Selected PAH Determination in Clean Waters; Comparacion Analitica de 4 Metodos Miniaturizados de Determinacion de PAHs mediante HPLC en Aguas

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, S.; Perez, R. M.; Fernandez, O.

    2012-04-11

    A study on the comparison and evaluation of 4 miniaturized extraction methods for the determination of selected PAHs in clear waters is presented. Four types of liquid-liquid extraction were used for chromatographic analysis by HPLC/ FD. The main objective was the optimization and development of simple, rapid and low cost methods, minimizing the use of extracting solvent volume. The work also includes a study on the scope of the methods developed at low and high levels of concentration. (Author) 13 refs.

  10. Synthesis of barium titanate crystalline nanoparticles using hydrothermal microwave method; Obtencao de nanoparticulas cristalinas de titanato de bario usando metodo hidrotermal assistido por microondas

    Energy Technology Data Exchange (ETDEWEB)

    Souza, A.E.; Silva, R.A.; Teixeira, S.R. [Universidade Estadual Paulista (DFQB/FCT/UNESP), Presidente Prudente, SP (Brazil). Dept. de Fisica, Quimica e Biologia. Lab. de Compositos e Ceramicas Funcionais; Moreira, M.L. [Universidade Federal de Sao Carlos (LiEC/UFSCAR), SP (Brazil). Lab. Interdisciplinar de Eletroquimica e Ceramica; Volanti, D.P.; Longo, E. [Universidade Estadual Paulista (LiEC/UNESP), Araraquara, SP (Brazil). Lab. Interdisciplinar de Eletroquimica e Ceramica

    2009-07-01

    The hydrothermal microwave method (HTMW) was used in the synthesis of barium titanate (BaTiO{sub 3}) nanoparticles. The solution was prepared in deionized water by using titanium (IV) isopropoxide (C{sub 12}H{sub 28}O{sub 4}Ti), barium chloride (BaCl{sub 2}.2H{sub 2}O) and potassium hydroxide (KOH). Afterwards it was heated in an adapted conventional microwave oven. The system is composed of a temperature controller with thermocouple, a hermetic camera of reaction made of teflon, a manometer and a safety valve. The solution was heated to 140 deg C, at a 140 deg C/min heating rate, and maintained at this temperature for 40 minutes. The obtained ceramic powder was characterized by using X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). The XRD data confirms the formation of a high crystalline ceramic material with perovskite structure. The FE-SEM images reveal morphologies with dimensions varying from 27 to 54 nm. (author)

  11. Effect tetrahydrofuran as solvent in the synthesis of mullite by the Pechini; Efeito do tetrahidrofurano como solvente na sintese de mulita pelo Metodo Pechini

    Energy Technology Data Exchange (ETDEWEB)

    Braga, A.N.S.; Santos, V.B. [Universidade Federal do Piaui (UFPI), Teresina, PI (Brazil); Simoes, V.N.; Neves, G.A.; Lira, H.L.; Menezes, R.R., E-mail: Aluskasimoes@homail.com [Universidade Federal de Campina Grande (UFCG), PB (Brazil)

    2016-07-01

    Mullite has been considered interesting in recent decades, due to its properties. The reaction mechanisms in the mullite formation may vary according to the precursor and the methods employed. In order to get mullite by a promising chemical synthesis and understudied in its production, this paper aims to synthesize mullite by Pechini method. We investigated the mullite crystallization kinetics from use of tetrahydrofuran as solvent. The samples were characterized by diffraction of X-ray (XRD), thermal analysis and scanning electron microscopy (SEM). The XRD results showed the formation of mullite, but together with the alpha alumina phase. Thermal analysis confirmed the disruption of the polymer chain prior to the formation of crystalline phases, with a total weight loss of 97%. The SEM showed a morphology consists of large aggregates, damaging the properties of refractory and performance of the material. (author)

  12. Determination of the biodiesel acidity index by potentiometric titration by using different methods; Determinacao do indice de acidez de biodiesel por titulacao potenciometrica utilizando-se diferentes metodos

    Energy Technology Data Exchange (ETDEWEB)

    Goncalves, Mary Ane; Sobral, Sidney Pereira; Borges, Paulo Paschoal [Instituto Nacional de Metrologia, Normalizacao e Qualidade Industrial (DIMCI/INMETRO), Duque de Caxias, RJ (Brazil). Diretoria de Metrologia Cientifica e Industrial], E-mail: magoncalves@inmetro.gov.br

    2009-07-01

    This work determined the index of the soybean/fat bio diesel through the potentiometric titration. Four different methods were used with variation of solvent and electrodes. The results were compared by F and t (Student) and it was verified that they were agreed in a 95% confidence interval.

  13. APLICAÇÃO DO METODO DE ANÁLISE HIERARQUICA (MAH NA ANALISE E AVALIAÇÃO DE IMPACTOS AMBIENTAIS DOS SISTEMAS DE TRANSPORTES URBANOS

    Directory of Open Access Journals (Sweden)

    Dominique Mouette

    2010-04-01

    Full Text Available

    O estudo de impacto ambiental envolve uma grande quantidade de critérios e parâmetros, sendo necessário o trabalho conjunto de uma equipe multidisciplinar. A complexidade dos impactos decorrentes dos sistemas de transporte urbanos que possuem características e magnitudes muito diferentes, somada a não obrigatoriedade do estudo, fizeram com que poucos estudos fossem efetuados e tornou evidente a necessidade de metodologias de avaliação dos mesmos. Este estudo aborda a utilização do Método de Analise Hierárquica, um procedimento multicriterial na analise e avaliação dos impactos ambientais dos sistemas de transportes urbanos.

    ABSTRACT

    The study of environmental impacts involves a large amount of criteria and parameters being necessary to work with a multisciplinary team. The impacts due to urban transportation are very complex having different characteristics and magnitude, besides that, in Brazil, these studies are not obliged by law. These facts leads to few studies of the environmental impacts and evidences the necessity of developing methodologies which makes possible the impact's evaluation. This study refers to the utilization of the Analytical Hierarchy Process, a multicriteria procedure in the evaluation and analysis of environmental impacts in urban transportation.

  14. Metodo y teoría en la evaluación de desayunos escolares Method and theory in school breakfast program evaluation

    Directory of Open Access Journals (Sweden)

    José Angel Vera Noriega

    2000-06-01

    Full Text Available Se llevó a cabo un estudio para evaluar el impacto de un programa de desayunos escolares en repertorios de discriminación, memoria y atención, comparando la zona urbana y rural. En la zona rural, fueron evaluados 300 niños elegidos al azar de los listados de preescolar que recibieron desayuno en los municipios en pobreza extrema y 150, que no lo recibieron. En la zona urbana, fueron evaluados 300 niños seleccionados aleatoriamente de los listados de las escuelas ubicadas en las colonias marginadas que recibieron desayuno y 150, que no recibieron desayuno. En una prueba sintética de atención y memoria, los resultados muestran que en la zona urbana no existen diferencias en las medidas atribuibles al programa de desayunos. En la zona rural, los niños mejoraron en sus ejecuciones y tiempos. Se encontraron algunas diferencias relacionadas con el impacto del desayuno sobre niños con diferente estado nutricional. Los niños rurales se beneficiaron más que los urbanos del programa.In order to compare and evaluate a school breakfast program impact and discrimination memory and attention repertories on urban and rural children. A study was done 300 rural children were randomly chosed to have breakfast and 150 didn´t have breakfast were evaluated and compared to 300 urban children who were randomly chose of extreme poverty marginal to have breakfast and 150 that didn´t have breakfast. A designed test to evaluate attention and memory shows that in urban children do not exist differences between measures of the behavior. Rural children improve their time and performance. It was found differences on breakfast impact based on nutrimental status. The rural children got more benefits than the urban children with the program.

  15. Implementation of the Bee Colony Optimization method for the design of fuel cells; Implementacion del metodo Bee Colony Optimization para el diseno de celdas de combustible

    Energy Technology Data Exchange (ETDEWEB)

    Esquivel E, J.; Ortiz S, J. J., E-mail: jaime.esquivel@fi.uaemex.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2011-11-15

    The present work shows the results obtained after applying the Bee Colony Optimization algorithm in the design of fuel cells for a BWR. The algorithm that is implemented, works following the behavior that have the bees when pollinating a flowers field. The bees carry out an exhaustive analysis in the cell, so they leave generating diverse configurations where different fuel bars are placed with different uranium enrichments to reach a value mean, with a specific number of gadolinium bars. The behavior of the generated cell is evaluated by means of the use of the commercial code CASMO-4, which shows the variables that allow fixing if the cell fulfills the requirements. Such variables are the local potential peak factor and the neutrons multiplication factor in an infinite medium. (Author)

  16. Vrednotenje ureditve notranjih kontrol z metodo COSO v trgovskem podjetju = Evaluation of Structures Regarding Internal Controls by Way of the COSO Method in a Trading Company

    Directory of Open Access Journals (Sweden)

    Karmen Markoja

    2009-12-01

    Full Text Available In carrying out internal audit, the selection of methodological tools forevaluation of internal control procedures, used to identify and evaluatekey places of exposure to risks in individual areas, is of partic ular importance. The approved coso method, taking into considerationthe wider meaning of control environment, has significantly contributedto integrated evaluation of internal control mechanisms in individualorganizations by defining the so-called soft controls. A possibleexample of internal audit implementation by using the coso methodon the example of a trading company is shown in the article. It introducesan example of how to apply the coso method in a given areaof internal audit, which can serve as a starting point for further auditprogramme development in accordance with the COSO method.

  17. Statistical method for the control of the electric power service interruptions (second part); Metodo de control estadistico de las interrupciones del servicio electrico (2a. parte)

    Energy Technology Data Exchange (ETDEWEB)

    Issouribehere, Pedro E.; Barbero, Juan C. [Universidad Nacional de La Plata (UNLP), Buenos Aires (Argentina). Facultad de Ingenieria. Inst. de Investigaciones Tecnologicas para Redes y Equipos Electricos (IITREE-LAT)]. E-mail: iitree@.ing.unlp.edu.ar; Martinez, Jorge L.; Galinski, Alejandro [Ente Nacional Regulador de la Electricidad (ENRE), Buenos Aires (Argentina)

    2001-07-01

    This paper presents the register of interruptions in application points of the concession areas of three concessionaires. The reliability indexes are presented of the controlled sites: interruption ratio {lambda}, time of average reposition r and unavailability Q obtained with the field information recompiled during three years from June 2000. The paper also obtains by concessionaire, the ratios of brief interruptions occurrence which constitutes another indicator of the Electric Service Quality.

  18. Advanced methods of analysis variance on scenarios of nuclear prospective; Metodos avanzados de analisis de varianza en escenarios de prospectiva nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Blazquez, J.; Montalvo, C.; Balbas, M.; Garcia-Berrocal, A.

    2011-07-01

    Traditional techniques of propagation of variance are not very reliable, because there are uncertainties of 100% relative value, for this so use less conventional methods, such as Beta distribution, Fuzzy Logic and the Monte Carlo Method.

  19. Analysis of mercury and selenium in biological samples by neutron activation analysis; Analise de mercurio e selenio em materiais biologicos pelo metodo de analise por ativacao com neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Catharino, Marilia Gabriela Miranda

    2002-07-01

    In the present work, hair samples from populations suspected of contamination by mercury, in the localities of Serra do Navio, Vila Nova and Tartarugalzinho, in the State of Amapa, were analyzed. Hair samples of children under odontopediatric treatment were also analyzed for mercury, in order to study the possibility of transfer of mercury from the dental amalgam and also to obtain data of hair mercury in a control population of children. Another step of the work was the development of a method for the determination of selenium, by using the short-lived radioisotope {sup 77}mSe. After the certification of the method it was applied to the analysis of hair, nails and a vitamin supplement. A comparison was made with the results obtain ed by using the long-lived radioisotope of selenium, {sup 75}Se. The results obtained for mercury in the hair samples of populations living in the State of Amapa have shown that the mercury concentrations in these populations are much higher than in the controls. As for the hair samples of children under treatment with mercury amalgam, no significant differences were found in the concentrations of mercury after the treatment. On the other hand, these data were important to obtain data for a control population of children. The results obtained by using the radioisotope {sup 77}mSe showed that the method developed was suitable for the analyzed matrixes and the results were similar to the ones obtained by employing the usual AANI method, with the radioisotope {sup 75}Se. (author)

  20. A Hybrid Method of medical Image Restoration with Gaussian and Impulsive Noise; Un Metodo Hibrido de Restauracion de Images Medidas con Ruido Gausino e Impulsivo

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez, M. G.; Vidal, V.; Verdu, G.; Mayo, P.; Rodenas, F.

    2011-07-01

    The noise removal techniques to restore noisy images is currently an important issue, for example, medical images obtained by X-ray computed tomography in noise due to the use of a small number of projections present noise of different types. In this paper we analyze and evaluate two techniques that separately each behaves efficiently for the removal of Gaussian and impulsive noise respectively, and combined to form a hybrid approach obtains very good performance with respect to quality in most different types of noise.

  1. Application of spectroscopic methods to the study of ionizing radiation effects in polymers; Aplicacion de metodos espectroscopicos para estudiar efectos de la radiacion en polimeros

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez P, G

    1996-12-31

    In general the interaction of ionizing radiation with polymers generates physic-chemical changes. Aiming to quantity these changes, three spectroscopic analytical techniques were used (UV, IR and EPR) and the chemical corrosion technique was used for three DSTN (CR39, Lexan and Makrofol) which were exposed to two radiation types: electrons and gammas. The effects of radiation are compared. Also a correlation between the UV and Vg results in function of dose is presented. The possible causes of the increase in chemical corrosion are discussed. (Author).

  2. Determination of the most reactivity control rod by pseudo-harmonics perturbation method; Determinacao da barra de controle mais reativa usando o metodo de pseudo-harmonicos

    Energy Technology Data Exchange (ETDEWEB)

    Freire, Fernando S.; Silva, Fernando C.; Martinez, Aquilino S. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Programa de Engenharia Nuclear]. E-mail: ffreire@con.ufrj.br; fernando@con.ufrj.br; aquilino@.con.ufrj.br

    2005-07-01

    Frequently it is necessary to compute the change in core multiplication caused by a change in the core temperature or composition. Even when this perturbation is localized, such as a control rod inserted into the core, one does not have to repeat the original criticality calculation, but instead we can use the well-known pseudo-harmonics perturbation method to express the corresponding change in the multiplication factor in terms of the neutron flux expanded in the basis vectors characterizing the unperturbed core. Therefore we may compute the control rod worth to find the most reactivity control rod to calculate the fast shutdown margin. In this thesis we propose a simple and precise method to identify the most reactivity control rod. (author)

  3. Valutazione analitica e applicazione clinica di un metodo Real Time PCR per il dosaggio della carica virale di Epstein-Barr virus

    Directory of Open Access Journals (Sweden)

    Maria Teresa Bortolin

    2004-03-01

    Full Text Available We assessed the performance of a Real Time PCR assay to be used for EBV viremia evaluation in clinical specimens. Sensitivity and intra-/interassay reproducibility were evaluated by using DNA serial dilutions from the Namalwa cell line. EBV DNA was analyzed in serum samples from 39 patients (pts with undifferentiated type nasopharyngeal carcinoma (UCNT, from 5 infectious mononucleosis (IM pts and from 18 healthy donors. Results obtained by Real Time PCR were compared with those obtained by quantitative competitive (QC-PCR assay.We thereafter measured the dynamics of EBV DNA load in 5 HIV-seropositive (HIV+ and 9 HIV-seronegative (HIV-, as controls pts with lymphoma, treated with high-dose chemotherapy (HCT followed by autologus stem-cell transplantation (ASCT. We found a sensitivity of 100% at 10 EBV copies. The Spearman correlation for both the intra- and the interassay reproducibility was statistically significant (r=0.99; p20 copies/reaction and >30% for EBV viral loads <20 copies/reaction. No EBV DNA was detected in healthy donors. Higher EBV DNA loads were found by Real Time PCR (range 1173-46328 copies/ml than by QC-PCR (range 450-5000 copies/ml (p<0.05. 54% of UCNT and 100% of IM pts were EBV DNA positive. Two HIV+(40% and 2 HIV-(22% pts with lymphoma had detectable EBV viremia during the follow-up. The Real Time PCR is a suitable technique for high-throughput screening and frequent monitoring of patients at risk for developing EBV-associated diseases.

  4. Photoluminescence evaluation of TiO{sub 2} synthesized by Pechini method; Avaliacao da fotoluminescencia do TiO{sub 2} sintetizado pelo metodo Pechini

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, D.S.; Diniz, V.C.S.; Dantas, J.; Araujo, P.M.A.G.; Costa, A.C.F.M., E-mail: dagobertoufcg@gmail.com [Universidade Federal de Campina Grande (UFCG), PB (Brazil). Programa de Pos-Graduacao em Ciencia e Engenharia de Materiais; Viana, R.S.; Junior, S.A. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. Quimica Fundamental; Torquato, R.A. [Universidade Federal da Paraiba (UFPB), Joao Pessoa, PB (Brazil). Dept. de Engenharia de Materiais

    2017-07-15

    Titanium dioxide (TiO{sub 2}) stands out for use in various applications mainly due to its properties of thermal and chemical stability and its excellent optical properties. However, these properties are dependent on the type and phase morphology, which is related to the TiO{sub 2} processing method. Thus, this paper proposed to synthesize TiO{sub 2} nanoparticles by polymeric precursor method with different polymorphs, and evaluate the influence of these phases in the photoluminescent properties. For this, the stoichiometric molar proportions of citric acid:metallic cations of 1:1, 2:1, 3:1, 4:1 and 5:1 were investigated. The nanoparticles were characterized by X-ray diffraction (XRD), infrared spectroscopy, textural analysis, scanning electron microscopy (SEM), excitation and emission spectroscopy and determination of the band gap by UV-Vis diffuse reflectance spectroscopy. The presence of anatase and rutile was confirmed by XRD in different proportions for each sample. The agglomerate size increased with the citric acid/metal cations ratio as observed by SEM. Concerning photoluminescence, the maximum intensity in the emission spectrum occurred at the wavelength of 533 nm for the 3:1 sample and the maximum intensity in the excitation spectrum occurred for the 2:1 sample at the wavelength of 451 nm. (author)

  5. Modelling of pressurized water reactor fuel, rod time dependent radial heat flow with boundary element method; Modeliranje spremenljivega radijalnega toplotnega toka tlacnovodne gorivne palice z metodo robnih elementov

    Energy Technology Data Exchange (ETDEWEB)

    Sarler, B [Institut Jozef Stefan, Ljubljana (Yugoslavia)

    1987-07-01

    The basic principles of the boundary element method numerical treatment of the radial flow heat diffusion equation are presented. The algorithm copes the time dependent Dirichlet and Neumann boundary conditions, temperature dependent material properties and regions from different materials in thermal contact. It is verified on the several analytically obtained test cases. The developed method is used for the modelling of unsteady radial heat flow in pressurized water reactor fuel rod. (author)

  6. Hydrocarbons thermal maturation: Leopatin method applied to the Parana basin; Maturacao termica de hidrocarbonetos: aplicacao do metodo de Lopatin a Bacia do Parana

    Energy Technology Data Exchange (ETDEWEB)

    Eston, Sergio Medici de; Jardim, Niza S

    1987-12-31

    One of the requirements for the existent of economic deposits of hydrocarbons is that the organic matter has undergone adequate thermal maturation. Several techniques have been proposed in order to quantity the catagenetic state of kerogen, and the Lopatin-Waples methodology permits quantification at any past time and does not require laboratory tests on samples of the material. For this reason it is an useful techniques for predicting mature zones using as basic information the thermal and subsidence histories of each stratum. Lopatin`s technique was applied to the Parana basin, with McKenzie`s crustal stretching model fitted to the data of 18 wells, and the areas predicted as mature for oil and/or gas were in good agreement with the field results. The technique predicted oil phone areas at the east border of the basin for the Ponta Grossa and Irati formation, and also that most of the thermal maturation occurred after the basalt flows of the Cretaceous period. (author) 41 refs., 6 figs., 6 tabs.

  7. Comparison between subjective and quantitative methods for assessing the resolution limit of radiographic systems; Comparacao entre metodos subjetivos e quantitativos na medida da resolucao limite de sistemas radiograficos

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez, Matheus; Oliveira, Marcela de; Miranda, Jose R.A. [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Botucatu, SP (Brazil). Inst. de Biociencias de Botucatu; Pina, Diana R., E-mail: matheus@ibb.unesp.br [UNESP, Botucatu, SP (Brazil). Faculdade de Medicina. Dept. de Doencas Tropicais e Diagnostico por Imagem

    2012-07-01

    The aim of this study was to compare two ways of measuring the resolution limit of radiographic systems, one subjective and one quantitative. To this end, nine images were acquired with different radiographic techniques using a pattern of bars and aluminum plates. With these images were acquired modulation transfer function (MTF) through the edge image obtained by the aluminum plate - the MTF 10% was measured on all images - and the variation of these points, which was faced with the evaluation obtained by the resolution limit of the standard bar. Although we have observed a greater variation between measurements obtained using the bar-pattern, the simplicity of this measuring technique favors the common use of the same. We concluded that, to optimize the quality control of radiographic equipment, it is suggested to measure the MTF at least in periods of time while the annual pattern of bars to be used in shorter time periods to measure changes in resolution of the system. (author)

  8. Standardization of the method for measurement of plasma estrone by radioimmunoassay; Padronizacao do metodo de dosagem de estrona plasmatica por radioimunoensaio

    Energy Technology Data Exchange (ETDEWEB)

    Vilanova, M.S.V.; Moreira, A.C.; Sala, M.M. de; Sa, M.F.S. de [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Faculdade de Medicina

    1994-10-01

    The present paper has as objective standardize a radioimmunoassay method for measurement of plasma estrone. Ethyl ether was used for plasma extraction. The sensitivity (Minimal detectable dose) was 3,7 pg/tube; the reproducibility (inter assay error) was 8,6%; the precision (intra assay error) was 4,1%. As a biological control the plasma estrone was ml and in 24 patients with polycystic ovarian syndrome (median = 77,9 pg/ml). (author). 6 refs, 2 figs, 2 tabs.

  9. Sequential method for the assessment of innovations in computer assisted industrial processes; Metodo secuencial para evaluacion de innovaciones en procesos industriales asistido por computadora

    Energy Technology Data Exchange (ETDEWEB)

    Suarez Antola, R [Universidad Catolica del Uruguay, Montevideo (Uruguay); Artucio, G [Ministerio de Industria Energia y Mineria. Direccion Nacional de Tecnologia Nuclear, Montevideo (Uruguay)

    1995-08-01

    A sequential method for the assessment of innovations in industrial processes is proposed, using suitable combinations of mathematical modelling and numerical simulation of dynamics. Some advantages and limitations of the proposed method are discussed. tabs.

  10. Metodo integrado para la gestion de Universidades basado en el Balanced Scorecard (bsc y el modelo europeo de calidad (efqm: caso U.C.S.M.

    Directory of Open Access Journals (Sweden)

    Horacio Vicente Barreda Tamayo

    2010-12-01

    Full Text Available El presente Trabajo realiza la propuesta de un Método Integrado que permite mejorar la competitividad en la Gestión de las Universidades, este método se basa: En una herramienta de Gestión Estratégica: el Balanced Scorecard (BSC, que fue creada por Kaplan y Norton en 1992; y En el Modelo Europeo de Calidad (EFQM, que fue desarrollado como un Modelo de Excelencia en 1991. La metodología utilizada consiste en analizar las características, ventajas y limitaciones del BSC y el EFQM para aplicarlos simultáneamente en la gestión de Tomando como base los 9 criterios del EFQM, se desarrolla un Mapa Estratégico del BSC, para que se alineen todas las perspectivas hacia el logro de los Objetivos Estratégicos de la Organización. El método integrado planteado se aplica en el caso de la Universidad Católica de Santa María (Arequipa- Perú, donde se analiza las ventajas que implicaría la implementación del mismo.

  11. Synthesis of lithium silicates generators of tritium by a modified method of combustion; Sintesis de silicatos de litio generadores de tritio por un metodo modificado de combustion

    Energy Technology Data Exchange (ETDEWEB)

    Cruz G, D

    2003-07-01

    The ceramics of lithium have been proposed as generating materials of tritium through the following reaction: {sup 6} Li + {sup 1} n {yields} {sup 4} He + {sup 3} H . In previous works carried out by Pfeiffer and collaborators, the lithium silicates generators of tritium were prepared using the following methods: reactions of solid state, precipitation and sol-gel synthesis. Although those methods have advantages, it is required of heating at high temperatures (900 C during four hours) to be able to obtain the crystalline compounds. Those products found in these works were diverse crystallization forms of the lithium silicates and of SiO{sub 2}, such as, Li{sub 2}SiO{sub 3}, Li{sub 2}Si{sub 2}0{sub 5}, Li{sub 4}SiO{sub 4}, and quartz (SiO{sub 2}). The combustion method uses exothermic reactions to take place ceramic compounds. The precursor solutions are mixtures of the nitrate of metal oxidizer and the fuels (urea, glycine, carbohydrazide). However the reported method in the literature, it is not useful to prepare lithium silicates, for what was modified using non oxidizers compounds. The lithium hydroxide (LiOH) and the silicic acid (H{sub 2}SiO{sub 3}) they were the compounds non oxidizers used, and the urea (CH{sub 4}N{sub 2}O) it was the one fuel. They were carried out two series of experiments; inside the series 1 of experiments are varied the molar ratio of lithium hydroxide and urea (LiOH : H{sub 2}SiO{sub 3} = 1, 2 and 3, LiOH : CH{sub 4}N{sub 2}O = 1, 2, 3, 4 and 5) and the prepared mixtures were taken to one muffle previously preheated to a temperature of 450 C during 5 minutes. In the series 2 of experiments was studied the effect of the temperature and of the washed with distilled water in the prepared samples with the following molar ratios: LiOH : H{sub 2}SiO{sub 3} : CH{sub 4}N{sub 2}O = 1:1:3, 2:1:3, 3:1:3 and 3:1:6, those which were heated to temperatures from 450 C up to 750 C and were washed. The obtained samples were characterized by X-ray diffraction (XRD), Infrared spectroscopy (I S), semiquantitative elemental analysis (EDS) and Thermal gravimetric analysis (TGA). It was found that the molar ratios more adequate of LiOH : H{sub 2}SiO{sub 3} : CH{sub 4}N{sub 2}O to produce Li{sub 2}SiO{sub 3} were: 3:1:3 and 3:1:6. The present carbonates in the powders prepared were eliminated in the second series by heating of the mixture to higher temperatures (650 C), or for washed of the same distilled water. The urea in excess produced coesite (SiO{sub 2}) as main product in the ceramics. Presently work was obtained, in accordance with the results, a sample of lithium silicate (Li{sub 2}SiO{sub 3}) not polluted with any type of compound that it contained coal. (Author)

  12. Characterization of an absorbed dose standard in water through ionometric methods; Caracterizacion de un patron de dosis absorbida en agua mediante metodos ionometricos

    Energy Technology Data Exchange (ETDEWEB)

    Vargas V, M.X

    2003-07-01

    In this work the unit of absorbed dose at the Secondary Standard Dosimetry Laboratory (SSDL) of Mexico, is characterized by means of the development of a primary standard of absorbed dose to water, D{sub agua}. The main purpose is to diminish the uncertainty in the service of dosimetric calibration of ionization chambers (employed in radiotherapy of extemal beams) that offers this laboratory. This thesis is composed of seven chapters: In Chapter 1 the position and justification of the problem is described, as well as the general and specific objectives. In Chapter 2, a presentation of the main quantities and units used in dosimetry is made, in accordance with the recommendations of the International Commission on Radiation Units and Measurements (ICRU) that establish the necessity to have a coherent system with the international system of units and dosimetric quantities. The concepts of equilibrium and transient equilibrium of charged particles (TCPE) are also presented, which are used later in the quantitative determination of D{sub agua}. Finally, since the proposed standard of D{sub agua} is of ionometric type, an explanation of the Bragg-Gray and Spencer-Attix cavity theories is made. These theories are the foundation of this type of standards. On the other hand, to guarantee the complete validity of the conditions demanded by these theories it is necessary to introduce correction factors. These factors are determined in Chapters 5 and 6. Since for the calculation of the correction factors Monte Carlo (MC) method is used in an important way, in Chapter 3 the fundamental concepts of this method are presented; in particular the principles of the code MCNP4C [Briesmeister 2000] are detailed, making emphasis on the basis of electron transport and variance reduction techniques used in this thesis. Because a phenomenological approach is carried out in the development of the standard of D{sub agua}, in Chapter 4 the characteristics of the Picker C/9 unit, the ionization chamber type CC01, series 131, built by Osterreichisches Forschungszentrum Seibersdorf, and the experimental conditions are shown. The characteristics of the complementary instrumentation employed in the experimental part of the work, are also presented. In Chapter 5, two ionometric methods for the calculation of the correction factors are presented: that of the Bureau International des Poids et Mesures (BIPM) and that of the International Atomic Energy Agency (IAEA). In the BIPM method emphasis is made in the MC simulation of the spectral fluence of the photons that emits the unit (using a realistic geometry and an equivalent one) as well as its validation by means of the air-kerma output factors and the percent depth doses in water, with the aid of the condition of TCPE that apply to the CC01-131 chamber. In particular, it is presented how the factor k{sub cav} is determined, employing MC simulation of two positions of the chamber (with the chamber axis parallel or perpendicular to the beam axis), and by means of a semi-analytic approach that uses the energy dissipation functions of Spencer for the parallel position. Finally the factor k{sub p} is determined for both orientations. In the case of the IAEA method, the expressions of the correction factors in the protocols TRS-277 and TRS-398 are shown. Chapter 6 presents results and discussion, and Chapter 7 presents conclusions and recommendations. In Chapter 6, the protocol of the BIPM/ISO/TAG [ISO 1992] for the calculation of the uncertainties is detailed, later the results and its discussion is made. The main conclusion obtained of these results is that the value of the D{sub agua} and its U for the BIPM method is bigger than that for the IAEA method. This conclusion has at least three meanings: First: The correction factors calculated using the BIPM method are overestimated, regarding the IAEA method. Second: The possible overestimation is consistent with the order of uncertainty with which are calculated, that is with the infrastructure that at the moment the SSDL-Mexico possesses to carry out the unit of absorbed dose to water (instrumentation, traceability of the electrometers, barometers, thermometers, calculation algorithms, time of machine, etc). Third: In this work it was shown the necessity to solve, if it exists, the ambiguity [Alvarez et al. 2002] of the models of the IAEA and the BIPM methods, when applying them to the design of the CC01-131 chamber. It was determined that, within the order of uncertainty with which the correction factors and the D{sub agua} were obtained, none of the two models presents the problem of ambiguity. (Author)

  13. Implementation of sum-peak method for standardization of positron emission radionuclides; Implementacao do metodo pico-soma para padronizacao de radionuclideos emissores de positrons

    Energy Technology Data Exchange (ETDEWEB)

    Fragoso, Maria da Conceicao de Farias; Oliveira, Mercia Liane de; Lima, Fernando Roberto de Andrade, E-mail: mcfragoso@cnen.gov.br [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil)

    2015-07-01

    Positron Emission Tomography (PET) is being increasingly recognized as an important quantitative imaging tool for diagnosis and assessing response to therapy. As correct dose administration plays a crucial part in nuclear medicine, it is important that the instruments used to assay the activity of the short-lived radionuclides are calibrated accurately, with traceability to the national or international standards. The sum-peak method has been widely used for radionuclide standardization. The purpose of this study was to implement the methodology for standardization of PET radiopharmaceuticals at the Regional Center for Nuclear Sciences of the Northeast (CRCN-NE). (author)

  14. Determination of the response time of pressure transducers using the direct method; Determinacao do tempo de resposta de transdutores de pressao utilizando o metodo de medida direta

    Energy Technology Data Exchange (ETDEWEB)

    Perillo, S R.P.

    1994-12-31

    The available methods to determine the response time of nuclear safety related pressure transducers are discussed, with emphasis to the direct method. In order to perform the experiments, a Hydraulic Ramp Generator was built. The equipment produces ramp pressure transients simultaneously to a reference transducer and to the transducer under test. The time lag between the output of the two transducers, when they reach a predetermined setpoint, is measured as the time delay of the transducer under test. Some results using the direct method to determine the time delay of pressure transducers (1 E Class Conventional) are presented. (author). 18 refs, 35 figs, 12 tabs.

  15. Doses determination in UCCA treatments with LDR brachytherapy using Monte Carlo methods; Determinacion de dosis en tratamientos de CaCU con braquiterapia LDR usando metodos Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Benites R, J. L. [Centro Estatal de Cancerologia de Nayarit, Comite de Investigacion, Calz. de la Cruz 118 sur, 63000 Tepic, Nayarit (Mexico); Vega C, H. R., E-mail: neutronesrapidos@gmail.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas, Zac. (Mexico)

    2017-10-15

    Using Monte Carlo methods, with the code MCNP5, a gynecological mannequin and a vaginal cylinder were modeled. The spatial distribution of absorbed dose rate in uterine cervical cancer (UCCA) treatments was determined under the modality of manual brachytherapy of low dose rate (B-LDR). The design of the model included the gynecological liquid water mannequin, a vaginal cylinder applicator of Lucite (PMMA) with hemisphere termination. The applicator was formed by a vaginal cylinder 10.3 cm long and 2 cm in diameter. This cylinder was mounted on a stainless steel tube 15.2 cm long by 0.6 cm in diameter. A linear array of four radioactive sources of Cesium 137 was inserted into the tube. 13 water cells of 0.5 cm in diameter were modeled around the vaginal cylinder and the absorbed dose was calculated in these. The distribution of the fluence of gamma photons in the mesh was calculated. It was found that the distribution of the absorbed dose is symmetric for cells located in the upper and lower part of the vaginal cylinder. The values of the absorbed dose rate were estimated for the date of manufacture of the sources. This result allows the use of the law of radioactive decay to determine the dose rate at any date of a gynecological treatment of B-LDR. (Author)

  16. Fire risk assessment method under the technical building code; Metodo de evaluacion del reisgo de incendio en el marco del Codigo Tecnico de la Edificacion

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Martin, J. C.; Diaz-Diaz, R.; Santos-Garcia, R.

    2010-07-01

    The high complexity of measuring and comparing the risk level of performance based design allowed by the Spain Building Code (CTE) and the lack of Spanish legislation on the matter makes a fire risk evaluation tool highly useful guiding the project's and the control authority over the feasibility of these complicated projects. A fire Risk Evaluation Method within the frame of the Spanish Building Code (MEREDICTE) has been developed trying to balance input sources, simplicity and clearness in its use. The number of parameters implied guarantees sound, exhaustive and reliable outputs. MEREDICTE is made of 73 parameters: 31 calculate potential risk and 42 obtain protection level. In an orientative way, MEREDICTE's parameters triple those of the most referred and extended evaluation method: the Gretener Method. The article shows the MEREDICTE technique and foundations, the methodology used in its investigation and development, its most significant innovation and its possible applications. Regarding the protection level, its formulation and applications re referred to the Windsor buildings of Madrid comparing the results obtained on the building as it was devastated by the fire of February 2005 and whether it fulfilled the Spanish building code conditions. (Author) 8 refs.

  17. Method for the development of emergency response preparedness for nuclear or radiological accidents; Metodo para el desarrollo de la preparacion de la respuesta a emergencias nucleares o radiologicas

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    This report supplements IAEA emergency preparedness guidance published in the 1980s, and is consistent with the new international guidance. It provides practical advice for the development of an emergency response capability based on the potential nature and magnitude of the risk. In order to apply this method, emergency planners should have a good understanding of the basic radiological emergency response principles. Therefore, other applicable international guidance should be reviewed before using this report. This report provides a practical step-by-step method for developing integrated user, local and national emergency response capabilities. It can also be used as the basis for conducting an audit of an existing emergency response capability.

  18. Investigation of the ROMP catalysis mechanism of norbornene using methods of density functional; Investigacao do mecanismo de catalise ROMP do norborneno utilizando metodos de funcional de densidade

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Carlos Pereira da, E-mail: carlosps1985@gmail.co [Institutor Federal de Educacao, Ciencia e Tecnologia do Piaui, Teresina, PI (Brazil); Lima, Francisco das Chagas Alves [Universidade Estadual do Piaui, Teresina, PI (Brazil). Coordenacao de Quimica; Leal, Regis Casimiro; Moita Neto, Jose Machado [Universidade Federal do Piaui (UFPI), Teresina, PI (Brazil)

    2010-07-01

    This work presents a density functional theory study of the norbornene ROMP metathesis reactions. The energies have been calculated in a Grubbs catalyst model Cl{sub 2}(PH{sub 3}){sub 2}Ru=CH{sub 2}. The geometries and energy profile are similar to the Grubbs methylidene (Cl{sub 2}(PCy{sub 3}){sub 2}Ru=CH{sub 2} real model. It was found that the metathesis reaction proceeds via associative mechanism (catalyst-norbornene) followed by dissociative substitution of a phosphine ligand with norbornene, giving a monophosphine complex. The results are in reasonable agreement with the available experimental data. The dissociation energy of the phosphines is predicted to be 23.2 kcal mol{sup -1}. (author)

  19. Hybrid nodal methods in the solution of the diffusion equations in X Y geometry; Metodos nodales hibridos en la solucion de las ecuaciones de difusion en geometria XY

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez M, N. [CFE, Carretera Cardel-Nautla Km. 43.5, 91680 Veracruz (Mexico); Alonso V, G.; Valle G, E. del [IPN-ESFM, 07738 Mexico D.F. (Mexico)]. e-mail: nhmiranda@mexico.com

    2003-07-01

    In 1979, Hennart and collaborators applied several schemes of classic finite element in the numerical solution of the diffusion equations in X Y geometry and stationary state. Almost two decades then, in 1996, himself and other collaborators carried out a similar work but using nodal schemes type finite element. Continuing in this last direction, in this work a group it is described a set of several Hybrid Nodal schemes denominated (NH) as well as their application to solve the diffusion equations in multigroup in stationary state and X Y geometry. The term hybrid nodal it means that such schemes interpolate not only Legendre moments of face and of cell but also the values of the scalar flow of neutrons in the four corners of each cell or element of the spatial discretization of the domain of interest. All the schemes here considered are polynomials like they were it their predecessors. Particularly, its have developed and applied eight different hybrid nodal schemes that its are very nearby related with those developed by Hennart and collaborators in the past. It is treated of schemes in those that nevertheless that decreases the number of interpolation parameters it is conserved the accurate in relation to the bi-quadratic and bi-cubic schemes. Of these eight, three were described and applied in a previous work. It is the bi-lineal classic scheme as well as the hybrid nodal schemes, bi-quadratic and bi-cubic for that here only are described the other 5 hybrid nodal schemes although they are provided numerical results for several test problems with all them. (Author)

  20. A digital method for period measurements in a nuclear reactor; Um metodo digital para medidas de periodo em um reator nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Mundim, Sergio Gorretta

    1971-02-15

    The present paper begins by giving a theoretical treatment for the nuclear reactor period. The conventional method of measuring the period is analysed and some previously developed digital methods are described. The paper criticises the latter, pointing out some deficiencies which the proposed process is able to eliminate. All errors connected with this process are also analysed. The paper presents suitable solutions to reduce them to a minimum. The total error is found to he less than the error presented by the other methods described. A digital period meter is designed with memory resources and an automatic scaler changer. Integrated circuits specifications are used in it. Real time experiments with nuclear reactors were made in order to check te validity of the method. The data acquired were applied to a simulated digital period meter implemented in a general purpose computer. The nuclear part of the work was developed at the 'Comissao Nacional de Energia Nuclear' and the simulation work was dane at the 'Departamento de Calculo Cientifico' of COPPE, which also advised the author in the completion of this thesis. (author)

  1. Calculation of Co2 emissions from the italian energy system; Calcolo delle emissioni di CO2 dal settore energetico italiano. 1990-2000. Metodo di riferimento IPCC

    Energy Technology Data Exchange (ETDEWEB)

    Contaldi, M. [Agenzia Nazionale per la Protezione dell' Ambiente, Rome (Italy); La Motta, S. [ENEA, Funzione Centrale Studi, Centro Ricerche Casaccia, Rome (Italy)

    2001-07-01

    The calculation of Co2 emissions from the Italian energy system is the object of this work. The inventory method used is the Reference Approach from the Intergovernmental Panel for Climate Change (IPCC, 1996 revised Guidelines for National Greenhouse Gas Inventories) and the energy consumption data are taken from the Italian Energy Balance edited by the Ministry of Industry. The years analysed are those from 1990 to 2000. [Italian] Lo scopo di questo lavoro e' quello di contabilizzare le emissioni di CO2 provenienti dal settore energetico per fonte di utilizzo dell'energia, a partire direttamente dal Bilancio Energetico Nazionale (Bilancio Energetico Nazionale, BEN, a cura del Ministero Industria, Commercio ed Artigianato) ed applicando all'Italia la metodologia di riferimento per il calcolo delle emissioni della CO2 elaborata dall'Intergovernmental Panel for Climate Change (IPCC, 1996 revised Guidelines for National Greenhouse Gas Inventories). Gli anni presi in considerazione in queto lavoro sono quelli dal 1990 al 2000.

  2. Analysis of medicinal plant extracts by neutron activation method; Analise de extratos de plantas medicinais pelo metodo de ativacao com neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Vaz, Sandra Muntz

    1995-12-31

    This dissertation has presented the results from analysis of medicinal plant extracts using neutron activation method. Instrumental neutron activation analysis was applied to the determination of the elements Al, Br, Ca, Ce, Cl, Cr, Cs, Fe, K, La, Mg, Mn, Na, Rb, Sb, Sc and Zn in medicinal extracts obtained from Achyrolcline satureoides DC, Casearia sylvestris, Centella asiatica, Citrus aurantium L., Solano lycocarpum, Solidago microglossa, Stryphnondedron barbatiman and Zingiber officinale R. plants. The elements Hg and Se were determined using radiochemical separation by means of retention of Se in HMD inorganic exchanger and solvent extraction of Hg by bismuth diethyl-dithiocarbamate solution. Precision and accuracy of the results have been evaluated by analysing reference materials. The therapeutic action of some elements found in plant extracts analyzed was briefly discussed 70 refs., 13 figs., 15 tabs

  3. ICP-MS: suitable method to study the metals distribution in estuarine regions; ICP-MS metodo adequado para o estudo da distribuicao de metais em regioes estuarinas

    Energy Technology Data Exchange (ETDEWEB)

    Vasconcelos, Danilo C.; Oliveira, Arno H. [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Dept. de Engenharia Nuclear]. E-mail: danilochagas@yahoo.com.br; heeren@nuclear.ufmg.br; Santos, Silvio J. dos; Brito, Veronica F.O.; Severo, Maria Isabel G. [Universidade Estadual de Santa Cruz, Ilheus, BA (Brazil). Dept. de Ciencias Biologicas

    2005-07-01

    Anthropogenic inputs of pollutants such as heavy metals into the marine environment have increased their levels to large extents within past a few decades. These pollutants tend to accumulate in the bottom sediments. As a result, ecosystems such as seaports or other industrialized coastal areas that have chronic inputs of metals have highly contaminated sediments. This characteristic has led to concerns over the ecological effects that may be associated with sediment quality. Of particular concern are toxic effects and the potential for bioaccumulation of metals in biota exposed to the sediments. The bivalves Crassostrea rhizophorae, Lucina pectinata and Mytella falcata have been used as biomonitors of trace metal contamination in two estuaries from Ilheus city, Bahia state, in Brazil. Bivalves, sediment and water samples were collected in March 2004 in Acuipe and Rio do Engenho mangroves. The proposed technique to analyze the studied matrices was the inductively coupled plasma mass spectrometry (ICP-MS). The results suggested that the studied molluscs are bioaccumulators of metals and showed the Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) as an adequate technique to determine a large range of inorganic elements, because its high sensibility and low detection limits. (author)

  4. Investigation of multi-phases dynamic systems by means of optical and electrochemical methods; Investigacion de sistemas dinamicos multifasicos mediante metodos opticos y electroquimicos

    Energy Technology Data Exchange (ETDEWEB)

    Sarmiento Martinez, Oscar

    2008-09-15

    During former investigations, the utilization of optical interferometric techniques was proposed to perform the monitoring of oxide layers growing or metallic degradation occurring in aluminum samples immersed in aqueous solutions, during initial stages of related oxidation processes without direct physical contact. Additionally a mathematical model was developed in order to obtain, from orthogonal displacements located in the metal surface during the anodic reaction, the metallic layer thickness loss or growth in the sample by interference fringes count. Here in this doctoral thesis, experimental and numerical results related to certain corrosion processes observed in different electrochemical systems using simultaneously Michelson interferometry optical monitoring and polarization curves electrochemical monitoring are presented. The qualitative and quantitative information resumed by important physical parameters related with the corrosion processes and their dynamics is analyzed, same as the alternated appearance and disappearance of interference patterns which optical visibility is lost and recovered as time goes by. On the other hand, a mathematical model for the optical-electrochemical system was developed in order to quantify metal loss or oxide layer growth in metallic samples, and also the reconstruction of conventional electrochemical dependences by using alternative experimental data obtained by interference maxima fringes counting. Lastly, and according to non-linear dynamical systems theoretical concepts, the non-linear parameters related to the existence of chaotic complex solutions are analyzed and discussed, based on experimental and numerical data obtained from the observation of corrosion processes of metals in aqueous solutions and hydrocarbons, during optical-electrochemical monitoring of our system. [Spanish] En un estudio previo, se propuso la utilizacion de tecnicas opticas interferometricas para monitorear el crecimiento de capas de oxidos o de la degradacion metalica en muestras de aluminio durante los estados iniciales de procesos de oxidacion en soluciones acuosas, sin medir contacto fisico alguno. Adicionalmente, se desarrollo un modelo matematico el cual permite, a partir de los desplazamientos ortogonales que ocurren en la superficie del metal durante la reaccion anodica, encontrar la perdida o crecimiento del espesor de la capa metalica de la muestra a partir del conteo de franjas de interferencia. En la presente tesis doctoral, se presentan resultados experimentales y numericos referentes a ciertos procesos de corrosion en diferentes sistemas electroquimicos utilizando simultaneamente el monitoreo optico mediante interferometria de Michelson y el monitoreo electroquimico mediante curvas de polarizacion. Se analiza la informacion tanto cualitativa como cuantitativa de importantes parametros fisicos relacionados con los procesos de corrosion y su dinamica, asi como la formacion de patrones de interferencia cuyo contraste optico se pierde con el paso de tiempo, para subitamente reaparecer y con ello nuevamente la aparicion del patron de interferencia inicial. Por otro lado, se desarrollo un modelo matematico a partir del sistema optico-electroquimico, el cual permite cuantificar mediante parametros opticos la perdida de material o crecimiento de oxido en metales, permitiendo reproducir las curvas electroquimicas mediante el conteo de maximos de interferencia. Finalmente, y de acuerdo a conceptos de la teoria de sistemas dinamicos no lineales, se analizan y discuten los parametros fisicos dinamicos no lineales relativos a la existencia de soluciones complejas de tipo caotico con base en los datos obtenidos de los procesos de corrosion en soluciones acuosas e hidrocarburos observados durante el monitoreo optico-electroquimico de nuestro sistema.

  5. Sintering kinetics and mass transport in ceramic engobes; Cinetica de sinterizacion y transporte de masa en engobes ceramicos por el metodo Pechini

    Energy Technology Data Exchange (ETDEWEB)

    Dal Bo, M.; Boschi, A. O.; Hotza, D.

    2013-10-01

    This work is concerned to study the sintering rate and mass transport mechanism in ceramic engobes. Specimens of engobes were prepared from a determined formulation by slip casting. Sintering was carried in two steps: (i) at constant heating rate of 7.5 degree centigrade/min and (ii) with an isothermal treatment, during 120 min. According to the dilatometric curves obtained with the engobe sintering during isothermal treatment, the dominant sintering mechanism and the rate of reactions, between the 775 and 975 degree centigrade, were determined. The results showed that between 775 and 800 degree centigrade, the sintering rate can be described by ln[d({Delta}L/L{sub 0})/dt] = -5.64 + 1.77.E10{sup -}3T. At higher temperatures, from 850 to 975 degree centigrade, this rate can be expressed by ln[d({Delta}L/L{sub 0})/ dt] = -30.73 + 3.E10{sup -}2T. The dominant transport mass mechanisms were the grain rearrangement, solution-precipitation and grain boundaries reaction. (Author)

  6. Aplicación del metodo delphi en el diseño de una investigación cuantitativa sobre el fenómeno FABLAB

    Directory of Open Access Journals (Sweden)

    Mª Elena García-Ruiz

    2018-05-01

    Full Text Available La facilidad de acceso a la tecnología ha propiciado la llegada de una nueva revolución industrial que capacita a los ciudadanos para dejar de ser meros usuarios y convertirse en creadores y constructores de sus propios bienes, apoyándose en las tendencias sociales basadas en la cultura colaborativa. El surgimiento de los Fablab -Fabrication Laboratory- como entornos que potencian dichas capacidades en los usuarios ha sido decisiva en esta democratización tecnológica, y sigue un ritmo creciente incesante, extendiéndose de forma llamativa por todo el planeta. A través de siete etapas, descritas en este artículo, se presenta el proceso de construcción y validación de la herramienta de obtención de información denominada FabLab Global Survey con el objetivo de conocer y caracteriza el fenómeno FabLab. La falta de referentes teóricos y la limitada bibliografía académica sobre el tema hace necesario el diseño de dicha herramienta basándonos en aportaciones de los expertos en el fenómeno FabLab y, para ello, se consideró adecuada su validación mediante el método Delphi, ya que permite la transmisión de la información subjetiva aportada por los expertos, respetando sus peculiaridades. El reto al que nos enfrentamos como investigadores estriba en nuestra capacidad de transformar los resultados obtenidos para su valoración a través de herramientas analíticas cuantitativas. Para compensar y equilibrar la subjetividad de las opiniones expresadas por el panel de expertos mediante escalas nominales, se emplea el Modelo de Torgerson, que permite un reescalamiento de la escala original cualitativa en una escala de intervalo (cuantitativa verificando la equivalencia entre ellas. Asimismo, y una vez contrastada la adecuación de la escala utilizada, se realiza un análisis cuantitativo y cualitativo de las aportaciones generadas por el grupo de expertos que permiten perfilar las características del cuestionario resultante. La excelente acogida de la Fablab Global Survey obtenida durante la distribución entre los gestores de los FabLabs -que señalan su idoneidad y acierto en la selección de cuestiones planteadas- muestra la adecuación del método Delphi para la generación de herramientas de investigación que permitan, como es el caso que nos ocupa, abrir nuevas líneas de investigación. The ease of access to technology has led to the arrival of a new industrial revolution that enables citizens to stop being mere users and become creators and builders of their own assets, relying on social trends based on collaborative culture. The emergence of the Fablab -Fabrication Laboratory- as environments that enhance these capacities in the users has been decisive in this technological democratization, and continues in an incessant rhythm, extending by the whole planet. Through seven stages, we describe in this article, the process of construction and validation of the information retrieval tool called FabLab Global Survey, with the objective of characterizing the FabLab phenomenon. The lack of theoretical references and the limited academic literature on the subject makes necessary to design such a tool based on contributions from the experts in the FabLab phenomenon and, for this purpose, it was considered appropriate to validate it using the Delphi method, since it allows the transmission of the subjective information provided by the experts, respecting their peculiarities. The challenge we face as researchers lies in our ability to transform the results obtained for their valuation through quantitative analytical tools. To compensate and balance the subjectivity of the opinions expressed by the panel of experts using nominal scales, the Torgerson`s Model is used, which allows a rescaling of the original qualitative scale on an interval scale (quantitative by verifying the equivalence between them. Likewise, and once the adequacy of the scale used is verified, a quantitative and qualitative analysis of the contributions generated by the group of experts is carried out, allowing to profile the characteristics of the resulting questionnaire. The excellent reception of the Fablab Global Survey obtained during the distribution among the managers of the FabLabs - which point out their suitability of the questions - shows the appropriateness of the Delphi method for the generation of research tools that allow, as it is the case in hand, open new lines of research.

  7. Comparative analysis of solution methods of the punctual kinetic equations; Analisis comparativo de metodos de solucion de las ecuaciones de cinetica puntual

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez S, A. [UNAM-LAIRN, Jiutepec, Morelos (Mexico)] e-mail: augusto_vib@yahoo.com.mx

    2003-07-01

    The following one written it presents a comparative analysis among different analytical solutions for the punctual kinetics equation, which present two variables of interest: a) the temporary behavior of the neutronic population, and b) The temporary behavior of the different groups of precursors of delayed neutrons. The first solution is based on a method that solves the transfer function of the differential equation for the neutronic population, in which intends to obtain the different poles that give the stability of this transfer function. In this section it is demonstrated that the temporary variation of the reactivity of the system can be managed as it is required, since the integration time for this method doesn't affect the result. However, the second solution is based on an iterative method like that of Runge-Kutta or the Euler method where the algorithm was only used to solve first order differential equations giving this way solution to each differential equation that conforms the equations of punctual kinetics. In this section it is demonstrated that only it can obtain a correct temporary behavior of the neutronic population when it is integrated on an interval of very short time, forcing to the temporary variation of the reactivity to change very quick way without one has some control about the time. In both methods the same change is used so much in the reactivity of the system like in the integration times, giving validity to the results graph the one the temporary behavior of the neutronic population vs. time. (Author)

  8. A digital method for period measurements in a nuclear reactor; Um metodo digital para medidas de periodo em um reator nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Mundim, Sergio Gorretta

    1971-02-15

    The present paper begins by giving a theoretical treatment for the nuclear reactor period. The conventional method of measuring the period is analysed and some previously developed digital methods are described. The paper criticises the latter, pointing out some deficiencies which the proposed process is able to eliminate. All errors connected with this process are also analysed. The paper presents suitable solutions to reduce them to a minimum. The total error is found to he less than the error presented by the other methods described. A digital period meter is designed with memory resources and an automatic scaler changer. Integrated circuits specifications are used in it. Real time experiments with nuclear reactors were made in order to check te validity of the method. The data acquired were applied to a simulated digital period meter implemented in a general purpose computer. The nuclear part of the work was developed at the 'Comissao Nacional de Energia Nuclear' and the simulation work was dane at the 'Departamento de Calculo Cientifico' of COPPE, which also advised the author in the completion of this thesis. (author)

  9. Sub-coulomb transfer method of a nucleon for measure orbital radii; Metodo de transferencia sub-coulombiana de un nucleon para medir radios orbitales

    Energy Technology Data Exchange (ETDEWEB)

    Aguilera R, E.F.; Murillo, G.; Ramirez, J.; Avila, O. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    1986-04-15

    The neutron transfer method is revised to measure neutron orbital radii and possible interest systems to apply it are determined. Its were carried out DWBA preliminary calculations for the system {sup 209} Bi(d,t) {sup 208} Bi. (Author)

  10. Las historias de la narrativa hispanoamericana: Criterios, metodos y ausencias. (Histories of the Latin-American Narrative: Criteria, Methods, and Absences).

    Science.gov (United States)

    Zavalo, Lauro

    This paper explains that materials on the teaching of Latin-American literature are sparse, even though most researchers in the field will dedicate much of their time to teaching. The paper adds that, in scholarly journals, little attention is given to teaching literature, and the topic is also absent from most academic congresses. The paper then…

  11. Risk assessment methods in radiotherapy: Probabilistic safety assessment (PSA); Los metodos de analisis de riesgo en radioterapia: Analisis Probabilistico de seguridad (APS)

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez Vera, M. L.; Perez Mulas, A.; Delgado, J. M.; Barrientos Ontero, M.; Somoano, F.; Alvarez Garcia, C.; Rodriguez Marti, M.

    2011-07-01

    The understanding of accidents that have occurred in radiotherapy and the lessons learned from them are very useful to prevent repetition, but there are other risks that have not been detected to date. With a view to identifying and preventing such risks, proactive methods successfully applied in other fields, such as probabilistic safety assessment (PSA), have been developed. (Author)

  12. Method for automatic re contouring straight adaptive radiotherapy for prostate cancer; Metodo para el recontorneo automatico del recto en radioterapia adaptativa en cancer de prostata

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Vila, B.; Garcia Vicente, F.; Aguilera, E. J.

    2011-07-01

    Outline of quickly and accurately the rectal wall is important in Image Guided Radiotherapy (IGRT in the acronym) as an organ of greatest influence in limiting the dose in the planning of radiation therapy in prostate cancer. Deformabies registration methods based on image intensity can not create a correct spatial transformation if there is no correspondence between the image and image planning session. The rectal content variation creates a non-correspondence in the image intensity becomes a major obstacle to the deformable registration based on image intensity.

  13. Method to determine the activity concentration and total activity of radioactive waste; Metodo para determinar la concentracion de actividad y actividad total de desechos radiactivos

    Energy Technology Data Exchange (ETDEWEB)

    Angeles C, A

    2001-02-15

    A characteristic system of radioactive waste is described to determine the concentration of radionuclides activity and the total activity of bundles of radioactive waste. The system this integrated by three subsystems: - Elevator of drums. - Electromechanics. - Gamma spectroscopy. In the system it is analyzed waste of issuing gamma specifically, and this designed for materials of relative low density and it analyzes materials of cylindrical recipients.

  14. Calculos de potenciais de ionização de algumas bases e aza-analogas utilizando o metodo semi-empirico HAM/3

    OpenAIRE

    Jose Jair Vianna Cirino

    1994-01-01

    Resumo: Inicialmente procedeu-se a otimização de geometrias das bases purinas guanina, 8-azaguanjna, xantina, 8-azaxantina e hipoxantina com o uso dos métodos semi-empíricos MNDO, AMI e MNDO-PM3. Nesta etapa também fez-se uso de métodos ab initio utilizando o conjunto de base cep-31G. Os potenciais de ionização dos elétrons do caroço das bases purinas foram calculados posteriormente por meio do método semi-empírico HAM/3 empregando as geometrias otimizadas pelos métodos semi-empíricos na etap...

  15. Analysis of the zirconia structure by `ab initio` and Rietveld methods; Analise da estrutura da zirconia por metodos `Ab initio` e de Rietveld

    Energy Technology Data Exchange (ETDEWEB)

    Bechepeche, A.P.; Nasar, R.S.; Longo, E. [Sao Carlos Univ., SP (Brazil). Dept. de Quimica; Treu Junior, O.; Varela, J.A. [UNESP, Araraquara, SP (Brazil). Inst. de Quimica

    1995-12-31

    The zirconia was doped with 0,113 mol of Mg O e 0,005 mol of Ti O{sub 2}, and it was calcined in 1550{sup d}eg C and it was analyzed by XRD. The results shows that pure zirconia contains 96,19% of monoclinic phase and 3,18% of cubic. However, the doping magnesia stabilizes the zirconia in 17,24 of monoclinic; 29,63 of tetragonal and 53,13% of cubic phase. The addition of titanium in zirconia gives 25,85% of tetragonal phase and 37,66% of cubic, and this shows the no stabilizing action of this transition metal. By the other side, the results with ab-initio calculating shows the same tendency resulting in the next values of total energy: pure zirconia - monoclinic -11.316,86ua; tetragonal -8742,09 ua and cubic -8742,80 ua and Zr O{sub 2} Ti O{sub 2} system - monoclinic -9463,02 ua, tetragonal -9459,39 ua and cubic -9459,97 ua (author) 3 figs., 2 tabs.

  16. Metodo y Proceso de la Investigacion Participativa en la Capacitacion Rural (The Method and Process of Participatory Research in Rural Leadership Training). Cuadernos del CREFAL 19.

    Science.gov (United States)

    de Schutter, Anton

    In participatory research, education and learner participation are directly connected. The document analyzes the role of a participatory research method in the basic education of rural adults. The different phases of the Participant Research method are presented, along with a profound analysis of both research and participation. The claim is that…

  17. Application of foresight methods in applications for patents and trademarks in Spain; Aplicacion de metodos de prevision en las solicitudes de patentes y marcas en Espana

    Energy Technology Data Exchange (ETDEWEB)

    Hidalgo Nuchera, A.; Glabaly Marquez, S.

    2011-07-01

    Patent and trademark offices which run according to principles of new management have an inherent need for dependable forecasting data in planning capacity and service levels. The predictive approach adopted for the time series of Spanish patents and trademarks applications (1979-2009) has been the use of different techniques of time series prediction in a short-term time horizon. The methods used can be grouped into two specifics areas: regression models of trends and time series models advanced. The results of this study show that it is possible to model the series of patents and trademarks applications with different models, especially ARIMA, with satisfactory model adjustment and relatively low error. (Author) 33 refs.

  18. Metodo de gestão em sistema de produção animal Management method in animal production system

    Directory of Open Access Journals (Sweden)

    Paulo Fernando Machado

    2009-07-01

    Full Text Available O sistema MDA de gerenciamento de explorações leiteiras teve origem em um conjunto de práticas gerenciais desenvolvidas e utilizadas eficientemente pelo setor industrial desde o início da década de 90. Foi desenvolvido aplicando-se os cinco princípios administrativos básicos para se atingir o sucesso nas empresas. Estes princípios, somados aos princípios de sobrevivência na atividade nortearam as características do Sistema MDA. Ele pode ser caracterizado como um sistema de gestão estratégica que se inicia com os fins em mente, ou seja, é condição básica para a realização de qualquer tarefa a definição, a priori, de metas e prazos. Com isso infere-se que há necessidade de se medir coisas. Se os resultados não forem alcançados, devem-se procurar as causas no treinamento dos funcionários ou nos métodos utilizados e nunca nas pessoas. Também, deve-se satisfazer a todos os interessados no negócio - os acionistas, os clientes, os funcionários e a sociedade.The MDA (Master Dairy Administration system was created as a result of management practices developed by and effectively utilized in the industrial sector since the early 1990's. It was designed by applying the five basic management principles to reach success in business. These principles, along with survival principles in the activity, delineated the features of the MDA System. It can be characterized as a strategic system which targets the ends from start, that is, the definition, a prior, of targets and deadlines is a primary condition to carry out any task. Therefore, there is a need to measure and follow up procedures. If results are not reached, questions must be placed on the training offered to employees or on the methods utilized, but never on the people. Moreover, all people interested in the business must have their expectations met - shareholders, customers, employees and the society.

  19. Arboreal biomass estimation: a comparison between neural networks and statistical methods; Estimativa de biomassa arborea: uma comparacao entre metodos estatisticos e redes neurais

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Arthur C.; Barros, Paulo L.C.; Monteiro, Jose H.A.; Rocha, Brigida R.P. [Universidade Federal do Para (DEEC/UFPA), Belem, PA (Brazil). Dept. de Engenharia Eletrica e Computacao. Grupo de Pesquisa ENERBIO], e-mails: arthur@ufpa.br, jhumberto01@yahoo.com.br, brigida@ufpa.br, paulo.contente@ufra.edu.br

    2006-07-01

    The current methodologies for calculating the volume of biomass and the consequent potential energy widely used in forest inventories, based primarily in statistical methodology to obtain their results. However, more recent techniques, based on the ability of nonlinear mappings, offered by artificial neural networks, have been used successfully in several areas of technology, with superior performance. This work shows a comparison between the statistical model to estimate the volume of trees and a model based on neural networks, which can be used with advantage for this activity related with biomass energy planning.

  20. Comparison between calculation methods of dose rates in gynecologic brachytherapy; Comparacion entre metodos de calculo de tasa de dosis en braquiterapia ginecologica8

    Energy Technology Data Exchange (ETDEWEB)

    Vianello, E.A.; Biaggio, M.F.; Dr, M.F.; Almeida, C.E. de [Laboratorio de Ciencias Radiologicas- (L.C.R.)-D.B.B.- UERJ- R. Sao Francisco Xavier, 524- Pav. HLC- sala 136- CEP 20550-013 Rio de Janeiro (Brazil)

    1998-12-31

    In treatments with radiations for gynecologic tumors is necessary to evaluate the quality of the results obtained by different calculation methods for the dose rates on the points of clinical interest (A, rectal, vesicle). The present work compares the results obtained by two methods. The Manual Calibration Method (MCM) tri dimensional (Vianello E., et.al. 1998), using orthogonal radiographs for each patient in treatment, and the Theraplan/T P-11 planning system (Thratonics International Limited 1990) this last one verified experimentally (Vianello et.al. 1996). The results show that MCM can be used in the physical-clinical practice with a percentile difference comparable at the computerized programs. (Author)

  1. Uso de métodos anticoncepcionais entre adolescentes universitários El uso de metodos anticonceptivos en adolescentes universitarios Use of contraceptive methods among university adolescents

    Directory of Open Access Journals (Sweden)

    Aline Salheb Alves

    2008-04-01

    Full Text Available Objetivou-se identificar o uso de métodos anticoncepcionais entre adolescentes, ingressantes de uma universidade pública paulista e descrever o perfil desses universitários quanto a algumas características sócio-demográficas. Foi utilizado um questionário e a amostra foi composta por 295 adolescentes. Relataram ter iniciado atividade sexual 48,8%. A idade média para o início foi aos 17 anos, e a maioria relatou ter usado um método contraceptivo. O método mais utilizado foi o preservativo e este em combinação com a pílula, principalmente. Observou-se que os adolescentes buscam informações, seja através de profissionais da saúde, professores, ou através de livros, com destaque para a mídia. Conclui-se que os universitários iniciam atividade sexual mais tardiamente e buscam conhecimento sobre anticoncepção.El objetivo de este trabajo es identificar el uso de los métodos anticonceptivos entre adolescentes, alumnos de una universidad paulista, y describir su perfil basados en algunas características socio-demográficas. Se utilizó un cuestionario aplicado a 295 adolescentes. El 48,8% relataron haber iniciado actividad sexual. En media, la edad para el inicio son los 17 años y la mayoría afirma haber usado métodos anticonceptivos. El más utilizado fue, principalmente, el preservativo combinado con la píldora. Se observó que los adolescentes buscan información consultando a profesionales de la salud, profesores o a través de libros, y sobretodo por los medios de comunicación. Se concluye que los universitarios inician su actividad sexual más tarde y buscan conocimiento sobre métodos anticonceptivos.The objective of this study was to identify the use of contraceptive methods among teenagers at a public University in São Paulo, as well as to describe their profile concerning social and demographic characteristics. A questionnaire was used and the sample was composed by 295 teenagers. The initiation of sexual activity was reported by 48,8%. The mean age was seventeen and most of them reported that they used some type of contraceptive method. The method used with highest frequency was the preservative, and this in combination with the pill. It could be observed that teenagers seek information through health professionals, teachers or books, and mainly media. It was concluded that the students had sexual initiation late and seek information about contraception.

  2. "Mastery Learning" Como Metodo Psicoeducativo para Ninos con Problemas Especificos de Aprendizaje. ("Mastery Learning" as a Psychoeducational Method for Children with Specific Learning Problems.)

    Science.gov (United States)

    Coya, Liliam de Barbosa; Perez-Coffie, Jorge

    1982-01-01

    "Mastery Learning" was compared with the "conventional" method of teaching reading skills to Puerto Rican children with specific learning disabilities. The "Mastery Learning" group showed significant gains in the cognitive and affective domains. Results suggested Mastery Learning is a more effective method of teaching…

  3. Accreditation of a system of extremity dosimetry: validation and uncertainty of method; Acreditacion de un sistema de dosimetria de extremidades: validacion e incertidumbre del metodo

    Energy Technology Data Exchange (ETDEWEB)

    Romero Gutierrez, A. M.; Rodriguez Jimenez, R.; Lopez Moyano, J. L.

    2013-07-01

    The authors' goal is to spread the practical experience gained during the accreditation process paying special attention to the process of method validation and estimation uncertainty of the dosimetry system. (Author)

  4. El uso del metodo MICMAC y MACTOR analisis prospectivo en un area operativa para la busqueda de la excelencia operativa a traves del Lean Manufacturing

    Directory of Open Access Journals (Sweden)

    Juan Baldemar Garza Villegas

    2011-07-01

    Full Text Available Presents the MICMAC and MACTOR prospective analysis study in an operational area which looks for world-class management with reference to the concepts of lean manufacturing. The results of a qualitative analysis and his conclusions are presented.

  5. Parametric identification of an asynchronous machine by the reactive power method; Identificacao parametrica de uma maquina assincrona pelo metodo da potencia reativa

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Alexandre Alves Sampaio e

    1996-07-01

    The obtention of the electrical and mechanical parameters of a squirrel-cage induction motor is investigated. Two methods of identification are studied: the reactive power method, used to determine the electrical parameters and an acceleration method on a startup test used to to find the mechanical ones. The method of reactive power is developed by analysing the machine steady state operation. In this analysis, a relationship between the electrical parameters and the reactive power is obtained. A minimization algorithm is used to determine the parameters based on this relationship. The acceleration method uses an acquisition of the transient variables, which is used in a recursive least square method furnishing the mechanical parameters. Both of methods are implemented on a special hardware and software system, consisting of sensors and A/D boards that make a digital acquisition of voltage, current and speed values. The validation procedures for the method and parameters are based on comparing between the real and simulated evaluation of the dynamical behavior of the motor in a startup test. The skin-effect influence over some of the motor parameters was also discussed. (author)

  6. The comparison of two methods to obtain human oral keratinocytes in primary culture; Comparacao de dois metodos de obtencao celular para cultura primaria de queratinocitos bucais humanos

    Energy Technology Data Exchange (ETDEWEB)

    Klingbeil, Maria Fatima Guarizo

    2006-07-01

    The therapeutic procedures frequently used in oral treatments for the pathological diseases are surgical, resulting in failures of the mucosal continuity.The possibility to obtain transplantable oral epithelia from an in vitro cell culture opens new utilization perspectives not only to where it comes from, but also as a reconstructive material for other parts of the human body, such as: urethra, epithelia corneo-limbal, cornea, ocular surface. Many researchers still use controversial methods for obtaining cells. It was therefore evaluated and compared the efficiency in both methods: enzymatic and direct explant to obtain oral keratinocytes from human oral mucosa. Fragments of intra oral epithelial tissues from healthy human subjects, undergoing dental surgeries, were donated to the research project. The keratinocytes were cultivated over a feeder-layer from a previously irradiated 3T3 Swiss albino fibroblasts. In this study it was compared the time needed in the cell obtention, the best cell amount between both methods, the life-span, the cell capacity to form an in vitro epithelia and its morphologic structure. The results in the assessment of both methods have shown the possibility to obtain keratinocytes from a small oral fragment, but at the same time we may verify the advantages and peculiar restrictions for each one of both analyzed methods. (author)

  7. Calculation methods of reactivity using derivatives of nuclear power and Filter fir; Metodos para o calculo da reatividade usando derivadas da potencia nuclear e o filtro FIR

    Energy Technology Data Exchange (ETDEWEB)

    Diaz, Daniel Suescun

    2007-07-01

    This work presents two new methods for the solution of the inverse point kinetics equation. The first method is based on the integration by parts of the integral of the inverse point kinetics equation, which results in a power series in terms of the nuclear power in time dependence. Applying some conditions to the nuclear power, the reactivity is represented as first and second derivatives of this nuclear power. This new calculation method for reactivity has special characteristics, amongst which the possibility of using different sampling periods, and the possibility of restarting the calculation, after its interruption associated it with a possible equipment malfunction, allowing the calculation of reactivity in a non-continuous way. Apart from this reactivity can be obtained with or without dependency on the nuclear power memory. The second method is based on the Laplace transform of the point kinetics equations, resulting in an expression equivalent to the inverse kinetics equation as a function of the power history. The reactivity can be written in terms of the summation of convolution with response to impulse, characteristic of a linear system. For its digital form the Z-transform is used, which is the discrete version of the Laplace transform. In this method it can be pointed out that the linear part is equivalent to a filter named Finite Impulse Response (Fir). The Fir filter will always be, stable and non-varying in time, and, apart from this, it can be implemented in the non-recursive way. This type of implementation does not require feedback, allowing the calculation of reactivity in a continuous way. The proposed methods were validated using signals with random noise and showing the relationship between the reactivity difference and the degree of the random noise. (author)

  8. Calibration methods of plane-parallel ionization chambers used in electron dosimetry; Metodos de calibracao de camaras de ionizacao de placas paralelas para dosimetria de feixes de eletrons

    Energy Technology Data Exchange (ETDEWEB)

    Bulla, Roseli Tadeu

    1999-07-01

    The use of linear accelerators in radiotherapy is of great importance in Medicine, and according to international recommendations the electron beam dosimetry has to be performed using plane-parallel ionization chambers, previously calibrated in standard gamma radiation fields at accredited laboratories. In this work, calibration methods of plane-parallel ionization chambers used in dosimetry procedures of high energy electron beams of clinical accelerators were presented, tested and intercompared. The experiments were carried out using gamma radiation beams of {sup 60} Co at the Calibration Laboratory of Clinical Dosemeters at IPEN and electron beams od 4 to 16 MeV at the Radiotherapy Department of Hospital Israelita Albert Einstein, Sao Paulo. A method was chosen to be established at IPEN. Proposals of the calibration procedure, calibration certificate and data sheets are presented. (author)

  9. Calibration and intercomparison methods of dose calibrators used in nuclear medicine facilities; Metodos de calibracao e de intercomparacao de calibradores de dose utilizados em servicos de medicina nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Alessandro Martins da

    1999-07-01

    Dose calibrators are used in most of the nuclear medicine facilities to determine the amount of radioactivity administered to a patient in a particular investigation or therapeutic procedure. It is therefore of vital importance that the equipment used presents good performance and is regular;y calibrated at a authorized laboratory. This occurs of adequate quality assurance procedures are carried out. Such quality control tests should be performed daily, other biannually or yearly, testing, for example, its accuracy and precision, the reproducibility and response linearity. In this work a commercial dose calibrator was calibrated with solution of radionuclides used in nuclear medicine. Simple instrument tests, such as response linearity and the response variation of the source volume increase at a constant source activity concentration, were performed. This instrument can now be used as a working standard for calibration of other dose calibrators/ An intercomparison procedure was proposed as a method of quality control of dose calibrators used in nuclear medicine facilities. (author)

  10. Noninvasive diagnostic methods in primary lung cancer Part one: sputum cytology and chest radiography; Metodos diagnosticos no invasivos en cancer pulmonar primario

    Energy Technology Data Exchange (ETDEWEB)

    Bastidas, Alirio; Garcia Herreros, Plutarco; Saavedra, Alfredo; Sanchez, Edgar

    2008-07-01

    Primary lung cancer is a world wide public health problem which generates immense costs to the health system and where its cure is only achieve by an early diagnosis associated to an opportune surgical treatment. For this purpose several non invasive diagnostic methods are currently available, among them the sputum cytology, chest radiography, computed tomography scanner and the positron emission tomography. In the present article, constituted by two parts, the usefulness of these diagnostic methods as screening, diagnosis, staging and follow up tools will be discuss on the basis of the current available literature for this type of neoplasm.

  11. Determination of bacterial endotoxin (pyrogen) in radiopharmaceuticals by the gel clot method. Validation; Determinacao de endotoxina bacteriana (pirogenio) em radiofarmacos pelo metodo de formacao de gel. Validacao

    Energy Technology Data Exchange (ETDEWEB)

    Fukumori, Neuza Taeko Okasaki

    2008-07-01

    Before the Limulus amebocyte lysate (LAL) test, the only available means of pirogenicity testing for parenteral drugs and medical devices was the United States Pharmacopoeia (USP) rabbit pyrogen test. Especially for radiopharmaceuticals, the LAL assay is the elective way to determine bacterial endotoxin. The aim of this work was to validate the gel clot method for some radiopharmaceuticals without measurable interference. The FDA's LALTest guideline defines interference as a condition that causes a significant difference between the endpoints of a positive water control and positive product control series using a standard endotoxin. Experiments were performed in accordance to the USP bacterial endotoxins test in the {sup 131}I- m-iodobenzylguanidine; the radioisotopes Gallium-67 and Thallium-201; the lyophilized reagents DTPA, Phytate, GHA, HSA and Colloidal Tin. The Maximum Valid Dilution (MVD) was calculated for each product based upon the clinical dose of the material and a twofold serial dilution below the MVD was performed in duplicate to detect interferences. The labeled sensitivity of the used LAL reagent was 0.125 EU mL{sup -1} (Endotoxin Units per milliliter). For validation, a dilution series was performed, a twofold dilution of control standard endotoxin (CSE) from 0.5 to 0.03 EU mL{sup -1}, to confirm the labeled sensitivity of the LAL reagent being tested in sterile and non pyrogenic water, in quadruplicate. The same dilution series was performed with the CSE and the product in the 1:100 dilution factor, in three consecutive batches of each radiopharmaceutical. The products {sup 131}I-m-iodobenzylguanidine, Gallium-67, Thallium-201, DTPA, HSA and Colloidal Tin were found compatible with the LAL test at a 1:100 dilution factor. Phytate and GHA showed some interference in the gel clot test. Other techniques to determine endotoxins as the chromogenic (color development) and the turbidimetric test (turbidity development), were also assessed to get valuable quantitative and qualitative information about the endotoxin concentration in samples. (author)

  12. UNA APROXIMACION A LOS DETERMINANTES SOCIOECONOMICOS DE LA MORTALIDAD INFANTIL Y DE NIÑEZ EN BOLIVIA: USO DE METODOS INDIRECTOS DE CALCULO DE MORTALIDAD Y ANALISIS BIVARIADO

    Directory of Open Access Journals (Sweden)

    Pamela Córdova

    2016-01-01

    Full Text Available A pesar de las importantes mejoras en los resultados de salud infantil y de niñez durante el Siglo XXI en América Latina, las tasas de mortalidad infantil y de niñez permanecen inaceptablemente altas en Bolivia encontrándose entre las más elevadas la región, solo por debajo de Haití, dirigiéndose a una deficiente salud infantil y de niñez. Estos resultados requieren de evidencia científica sobre la mejor manera de hacer frente a sus determinantes. Este estudio aproxima, teóricamente, mediante el marco teórico propuesto por Mosley-Chen y Sastry, los determinantes de la mortalidad infantil y de niñez en Bolivia enfocados en características individuales, del hogar y contextual. Además se examina de manera preliminar los niveles y magnitudes de la mortalidad mediante el uso de métodos directos e indirectos de estimación mediante la técnica propuesta por la versión Trussel y la versión Palloni-Heligman del Método de Brass y se realiza un análisis bivariado que da cuenta de relaciones existentes entre la mortalidad infantil y de niñez y las variables a nivel del hogar, individual y contextual relacionado con las políticas públicas.

  13. Methods for fitting of efficiency curves obtained by means of HPGe gamma rays spectrometers; Metodos de ajuste de curvas de eficiencia obtidas por meio de espectrometros de HPGe

    Energy Technology Data Exchange (ETDEWEB)

    Cardoso, Vanderlei

    2002-07-01

    The present work describes a few methodologies developed for fitting efficiency curves obtained by means of a HPGe gamma-ray spectrometer. The interpolated values were determined by simple polynomial fitting and polynomial fitting between the ratio of experimental peak efficiency and total efficiency, calculated by Monte Carlo technique, as a function of gamma-ray energy. Moreover, non-linear fitting has been performed using a segmented polynomial function and applying the Gauss-Marquardt method. For the peak area obtainment different methodologies were developed in order to estimate the background area under the peak. This information was obtained by numerical integration or by using analytical functions associated to the background. One non-calibrated radioactive source has been included in the curve efficiency in order to provide additional calibration points. As a by-product, it was possible to determine the activity of this non-calibrated source. For all fittings developed in the present work the covariance matrix methodology was used, which is an essential procedure in order to give a complete description of the partial uncertainties involved. (author)

  14. Coincidence in the dose estimation in a OEP by different methods; Coincidencia en la estimacion de dosis en un POE por diferentes metodos

    Energy Technology Data Exchange (ETDEWEB)

    Guerrero C, C.; Arceo M, C.; Brena V, M. [ININ, Km. 36.5, Carretera Mexico-Toluca, 52750 La Marquesa, Estado de Mexico (Mexico)]. e-mail: cgc@nuclear.inin.mx

    2007-07-01

    The case of an apparent overexposure to radiation according to that indicated for the thermoluminescent dosemeter 81.59 mSv (TLD) of a occupationally exposed hard-working (POE), for that was practiced the study of biological dosimetry. The estimated dose was 0.12 Gy with which was proven the marked dose registration by the TLD dosemeter. It was concluded that both doses are the same ones. (Author)

  15. Application of Monte Carlo simulation to the standardization of positron emitting radionuclides; Aplicacao do metodo de Monte Carlo na padronizacao de radionuclideos emissores de positrons

    Energy Technology Data Exchange (ETDEWEB)

    Tongu, Margareth Lika Onishi

    2009-07-01

    Since 1967, the Nuclear Metrology Laboratory (LNM) at the Nuclear and Energy Research (IPEN) in Sao Paulo, Brazil, has developed radionuclide standardization methods and measurements of the Gamma-ray emission probabilities per decay by means of 4{pi}{beta}-{gamma} coincidence system, a high accuracy primary method for determining disintegration rate of radionuclides of interest. In 2001 the LNM started a research field on modeling, based on Monte Carlo method, of all the system components, including radiation detectors and radionuclide decay processes. This methodology allows the simulation of the detection process in a 4{pi}{beta}-{gamma} system, determining theoretically the observed activity as a function of the 4{pi}{beta} detector efficiency, enabling the prediction of the behavior of the extrapolation curve and optimizing a detailed planning of the experiment before starting the measurements. One of the objectives of the present work is the improvement of the 4{pi} proportional counter modeling, presenting a detailed description of the source holder and radioactive source material, as well as absorbers placed around the source. The simulation of radiation transport through the detectors has been carried out using code MCNPX. The main focus of the present work is on Monte Carlo modeling of the standardization of positron emitting radionuclides associated (or not) with electron capture and accompanied (or not) by the emission of Gamma radiation. One difficulty in this modeling is to simulate the detection of the annihilation Gamma ray, which arise in the process of positron absorption within the 4{pi} detector. The methodology was applied to radionuclides {sup 18}F and {sup 22}Na. (author)

  16. Validation of analytical method to calculate the concentration of conjugated monoclonal antibody; Validacao de metodo analitico para calculo de concentracao de anticorpo monoclonal conjugado

    Energy Technology Data Exchange (ETDEWEB)

    Alcarde, Lais F.; Massicano, Adriana V.F.; Oliveira, Ricardo S.; Araujo, Elaine B. de, E-mail: lais_alcarde@hotmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    The objective of this study was to develop a quantitative analytical method using high performance liquid chromatography (HPLC) to determine the antibody concentration in conjunction with bifunctional chelator. Assays were performed using a high performance liquid chromatograph, and the following conditions were used: flow rate of 1 mL / min, 15 min run time, 0.2 M sodium phosphate buffer pH 7.0 as the mobile phase and column of molecular exclusion BioSep SEC S-3000 (300 x 7.8 mm, 5 μM - Phenomenex). The calibration curve was obtained with AcM diluted in 0.2 M sodium phosphate buffer pH 7.0 by serial dilution, yielding the concentrations: 400 μg/mL, 200 μg/mL, 100 μg/mL, 50 μg/mL, 25 μg/mL and 12.5 μg/mL. From the calibration curve calculated the equation of the line and with it the concentration of the immunoconjugate. To ensure the validity of the method accuracy and precision studies were conducted. The accuracy test consisted in the evaluation of 3 samples of known concentration, being this test performed with low concentrations (50 μg/mL), medium (100 μg/mL) and high (200 μg/mL). The precision test consisted of 3 consecutive measurements of one sample of known concentration, subject to the conditions set forth above for the other tests. The correlation coefficient of the standard curve was greater than 97%, the accuracy was satisfactory at low concentrations as well as accuracy. The method was validated by showing it for the accurate and precise determination of the concentration of the immunoconjugate. Furthermore, this assay was found to be extremely important, because using the correct mass of the protein, the radiochemical purity of the radioimmunoconjugate was above 95% in all studies.

  17. Trace element determination in human bones using the neutron activation analysis method; Determinacao de elementos traco em ossos humanos pelo metodo de analise por ativacao com neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Kramarski, Sila; Saiki, Mitiko [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil); Borelli, Aurelio [Sao Paulo Univ., SP (Brazil). Faculdade de Medicina. Lab. de Nutricao Humana; Batalha, Joao R.F. [Universidade de Mogi das Cruzes, SP (Brazil). Faculdade de Medicina

    1997-10-01

    This work presents the results obtained in the analysis of rib bone samples from normal human individuals by applying instrumental neutron activation analysis. In these analyses, the elements Br, Cl, Fe, K, Mg, Na, Rb, Sr and Zn were found at the ppm level and the elements Ca and P at the level of percentage. The precision and the of the results were evaluated by using biological reference materials NIST SRM 1577a Bovine Liver, IAEA A-11 Milk powder, NIES CRM 9 Sargasso e NIES CRM 10A Rice Flour Unpolished. (author). 5 refs., 3 tabs.

  18. How to identify partial exposures to ionizing radiation? Proposal for a cytogenetic method; Como identificar exposicoes parciais as radiacoes ionizantes? Proposta de um metodo citogenetico

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, T.S.; Silva, E.B.; Pinto, M.M.P.L.; Amaral, A., E-mail: thiagosalazar@hotmail.com [Universidade Federal de Pernambuco (LAMBDA/UFPE), Recife, PE (Brazil). Departamento de Energia Nuclear. Lab. de Modelagem e Biodosimetria Aplicada; Lloyd, David [Health Protection Agency, Oxford (United Kingdom). Radiation Protection Division

    2013-08-15

    In cases of radiological incidents or in occupational exposures to ionizing radiation, the majority of exposures are not related to the total body, but only partial. In this context, if the cytogenetic dosimetry is performed, there will be an underestimation of the absorbed dose due to the dilution of irradiated cells with non-irradiated cells. Considering the norms of NR 32 - Safety and Health in the Work of Health Service - which recommends cytogenetic dosimetry in the investigation of accidental exposures to ionizing radiations, it is necessary to develop of a tool to provide a better identification of partial exposures. With this aim, a partial body exposure was simulated by mixing, in vitro, 70% of blood irradiated with 4 Gy of X-rays with 30% of unirradiated blood from the same healthy donor. Aliquots of this mixture were cultured for 48 and 72 hours. Prolonging the time of cell culture from 48 to 72 hours produced no significant change in the yield of dicentrics. However, when only M1 (first division cells) were analyzed, the frequency of dicentrics per cell was increased. Prolonging the time of cell culture allowed cells in mitotic delay by irradiation to reach metaphase, and thus provides enough time for the damage to be visualized. The results of this research present the proposed method as an important tool in the investigation of exposed individuals, allowing associating the cytogenetic analysis with the real percentage of irradiated cells, contributing significantly for the decision making in terms of occupational health. (author)

  19. Three dimensional simulation of compressible and incompressible flows through the finite element method; Simulacao tridimensional de escoamentos compressiveis e incompressiveis atraves do metodo dos elementos finitos

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Gustavo Koury

    2004-11-15

    Although incompressible fluid flows can be regarded as a particular case of a general problem, numerical methods and the mathematical formulation aimed to solve compressible and incompressible flows have their own peculiarities, in such a way, that it is generally not possible to attain both regimes with a single approach. In this work, we start from a typically compressible formulation, slightly modified to make use of pressure variables and, through augmenting the stabilising parameters, we end up with a simplified model which is able to deal with a wide range of flow regimes, from supersonic to low speed gas flows. The resulting methodology is flexible enough to allow for the simulation of liquid flows as well. Examples using conservative and pressure variables are shown and the results are compared to those published in the literature, in order to validate the method. (author)

  20. GPR data modeling by using the Finite Difference Time Domain (FDTD) methods; Modelagem de dados de GPR atraves do metodo FDTD

    Energy Technology Data Exchange (ETDEWEB)

    Dias, Gleide A.N.; Silva, Jadir C.; Rocha, Paula F.; Costa, Jorge L. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Dept. de Geologia]. E-mail: gleidalencar@hotmail.com.br; jadir@geologia.ufrj.br; ferrucio@acd.ufrj.br; jotalc@yahoo.com.br

    2003-07-01

    Presently the oil industry has shown the importance of defining the structural framework of reservoirs. This study intends to contribute for the solution of this problem, using synthetic models in order to evaluate the electromagnetic signal due to a certain target. Use was made of an algorithm, which is based in the Finite Difference Time Domain Methods (FDTD). The simulated results of this survey found the best parameters for the chosen frequencies. In the present study there were simulated polarization, geometry and constitutive parameters (dielectric permittivity and electric conductivity). The results, using frequencies of 50 and 100 MHz, show clearly the effects of the electromagnetic waves attenuation and their problems related with signal resolution of targets in depth. (author)

  1. Stime della biomassa marina attraverso il metodo acustico: discernimento delle specie e gestione delle risorse ittiche - Acoustical estimation of fish biomass: species identification and stocks management

    Directory of Open Access Journals (Sweden)

    Víctor Espinosa

    2015-09-01

    Full Text Available L’acustica è alla base delle più importanti tecnologie nelle telecomunicazioni subacquee, nonché nel rilevamento e nella determinazione dei target acustici nei mezzi acquatici. Le misure a multi-frequenza sono lo strumento principale per l’identificazione selettiva delle specie marine e per la pesca sostenibile. Lo sviluppo di sistemi a larga banda larga e le tecniche basate su sonar multi-beam costituiscono l'attuale sfida per gli scienziati e gli sviluppatori. Al contempo, sistemi più semplici ed economicamente efficienti, come boe satellitari, sono in grado di offrire informazioni per il monitoraggio degli ecosistemi o l’individuazione di specie bersaglio nella pesca marittima. ------ Acoustics is the basics of the most important technologies for underwater telecommunication, as well as for target detection and identification in the aquatic media. Multiple frequency measurements are the key for species discrimination and open the door for sustainable fisheries. The development of wider broadband systems and quantitative multi-beam sonars and processing techniques constitute the present challenge for scientists and developers. In parallel, simpler and cost-efficient systems like satellite buoys can offer clue information for marine ecosystem monitoring or target species fisheries.

  2. Evaluation of the open vial method in the radon measurement; Evaluacion del metodo del vial abierto en la medicion de radon

    Energy Technology Data Exchange (ETDEWEB)

    Lopez del Rio, H.; Davila R, J. I.; Mireles G, F., E-mail: hlopezdelrio@hotmail.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico)

    2014-10-15

    The open vial method is a simple technique, under-utilized but that take advantage of the great radon solubility in organic solvents, therefore applies in the measurement of the radon concentration exhaled in soil. The method consists on the exposition to the gas radon of an open vial with scintillating solution. An integral mathematical model for indoors that describes the emanation processes and gas radon exhalation was developed, as well as the radon dissolution in the scintillation liquid, besides obtaining the characteristic parameters of the experimental system proposed for the radon concentration calculation exhaled by soils. Two experimental arrangements were designed with exposition cameras of 12 and 6 L and quantity of different soil. The open vial was prepared with a mixture of 8 ml of deionized water and 12 ml of scintillation liquid OptiPhase Hi Safe 3 in polyethylene vials; the measurements of the dissolved radon were carried out in scintillation liquid equipment. As a result, on average 2.0% of the exhaled radon is dissolved in the open vial and the dissolved fraction is independent of the experimental arrangement. Also was observed that the exposition time does not affect the radon dissolution significantly, in correspondence with the reported in the literature. (Author)

  3. The Muhlbauer method for pipeline risk management in onshore environment; O metodo de Muhlbauer para gerenciamento de risco em linhas de dutos em ambiente 'onshore'

    Energy Technology Data Exchange (ETDEWEB)

    Schafer, Alexandro G.; Miguelis, Paula M.F. [UNIPAMPA, RS (Brazil)

    2008-07-01

    There are several methods for the risk assessment and risk management applied to pipelines, among them the Muhlbauer's Method. W. Kent Muhlbauer is an internationally recognized authority on pipeline risk management. He made a detailed identification about 300 distinct conditions that influence the risk assessment in pipelines and he proposed a score system that is known as method of Muhlbauer. The purpose of this model is to evaluate the public exposure to the risk and identify ways for management that risk in fact. The assessment is made by the attribution of quantitative values to the several items that influences in the pipeline risk. This paper approaches the Muhlbauer's basic model for risk assessment and management in pipelines. In the beginning, the basic model for risk assessment is presented, and methodology for pipelines in onshore environment is detailed. After, presents major items in risk assessment and this relative score. Finally, present the additional modules for Muhlbauer's method customizing. (author)

  4. Hydrocarbons thermal maturation: Leopatin method applied to the Parana basin; Maturacao termica de hidrocarbonetos: aplicacao do metodo de Lopatin a Bacia do Parana

    Energy Technology Data Exchange (ETDEWEB)

    Eston, Sergio Medici de; Jardim, Niza S.

    1986-12-31

    One of the requirements for the existent of economic deposits of hydrocarbons is that the organic matter has undergone adequate thermal maturation. Several techniques have been proposed in order to quantity the catagenetic state of kerogen, and the Lopatin-Waples methodology permits quantification at any past time and does not require laboratory tests on samples of the material. For this reason it is an useful techniques for predicting mature zones using as basic information the thermal and subsidence histories of each stratum. Lopatin`s technique was applied to the Parana basin, with McKenzie`s crustal stretching model fitted to the data of 18 wells, and the areas predicted as mature for oil and/or gas were in good agreement with the field results. The technique predicted oil phone areas at the east border of the basin for the Ponta Grossa and Irati formation, and also that most of the thermal maturation occurred after the basalt flows of the Cretaceous period. (author) 41 refs., 6 figs., 6 tabs.

  5. The Marine Magnetotelluric Method (MMT) applied of hydrocarbons exploration in Brazilian waters; Aplicacao do Metodo Magnetotelurico Marinho (MMT) na exploracao de hidrocarbonetos em aguas brasileiras

    Energy Technology Data Exchange (ETDEWEB)

    Pinto, Vinicius R.; Flexor, Jean M.; La Terra, Emanuele F.; Fontes, Sergio L. [Observatorio Nacional do Brasil, Rio de Janeiro, RJ (Brazil); Lugao, Patricia P. [Schlumberger, Rio de Janeiro, RJ (Brazil). Western-Geco

    2008-07-01

    Magnetotellurics (MT) is a natural-source, electromagnetic geophysical method of imaging structures below the earth's surface. It is used to map the subsurface Earth's resistivity by measuring the naturally occurring electric and magnetic fields at the Earth's surface. These natural EM fields are generated in the Earth's atmosphere mainly by lightning strokes and by interactions between the solar wind and the ionosphere. Natural variations in the earth's magnetic field induce electric currents (or telluric currents) under the earth's surface. Concurrent measurements of orthogonal components of the electric and magnetic fields allow for the calculation of the impedance tensor, which is complex and frequency-dependent and from which it is possible to gain insight into the resistivity structure of the surrounding material. The marine magnetotelluric method (MMT) is the application of MT method to investigate the sea-floor resistivity's distribution. A MMT sounding with 96 stations was realized in the region of Santos Basin on a subsalt section to assist the interpretation of seismic data in order to estimate the depth of base of the salt (subsalt) since this imaging in general is problematic. The high contrast of the electrical resistivity between the salt and the surrounding sediments is an excellent objective and it constitutes a great opportunity to test the applicability of the MMT method in oil exploration studies. The geological interpretation of the seismic profile of the studied area shows the existence of several bodies of salt with depths of the base that could vary more from 7000 m to more than 9000 m. The top of the body of more important salt of the profile begins to the 3500 m and your base is not solved by the seismic sign that it reaches a maximum depth of 9000 m. The MMT data of the central profile were submitted an inversion procedure - 2D by using the non linear conjugate gradients that produces smooth models for the resistivity structure. The TE and TM modes were used simultaneously for the inversion, with admitted errors of 6%, for the resistivity and the phase. The inversions produced resistivity anomalies well delimited with a correct estimate of the position and of the depth reached by the bodies of salt. (author)

  6. Computer simulating for oil fields with artificial elevation method by electrical submersible pump; Simulacao computacional para pocos de petroleo com metodo de elevacao artificial por bombeio centrifugo submerso

    Energy Technology Data Exchange (ETDEWEB)

    Batista, Evellyne da Silva; Maitelli, Andre Laurindo [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil); Costa, Rutacio de Oliveira [PETROBRAS S.A., Natal, RN (Brazil). Unidade de Negocio RN/CE; Barbosa, Tiago de Souza [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Dept. de Engenharia de Computacao

    2008-07-01

    The architecture heterogeneities and petrophysical properties of carbonate reservoirs result from a combination of platform morphology, related depositional environments, relative sea level changes and diagenetic events. The reservoir layering built for static and dynamic modelling purposes should reflect the key heterogeneities (depositional or diagenetic) which govern the fluid flow patterns. The layering needs to be adapted to the goal of the modelling, ranging from full field computations of hydrocarbon volumes, to sector-based fine-scale simulations to test the recovery improvement. This paper illustrates various reservoir layering types, including schemes dominated by depositional architecture, and those more driven by the diagenetic overprint. The examples include carbonate platform reservoirs from different stratigraphic settings (Tertiary, Cretaceous, Jurassic and Permian) and different regions (Europe, Africa and Middle East areas). This review shows how significant stratigraphic surfaces (such as sequence boundaries or maximum flooding) with their associated facies shifts, can be often considered as key markers to constrain the reservoir layering. Conversely, how diagenesis (dolomitization and karst development), resulting in units with particular poroperm characteristics, may significantly overprint the primary reservoir architecture by generating flow units which cross-cut depositional sequences. To demonstrate how diagenetic processes can create reservoir bodies with geometries that cross-cut the depositional fabric, different types of dolomitization and karst development are illustrated. (author)

  7. Influence of incorporation method of sulfated zirconia in MCM-41 molecular sieve; Influencia do metodo de incorporacao da zirconia sulfatada na peneira molecular MCM-41

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, C.E.; Santos, J.S.B.; Cavalcante, J.N.A.; Andrade, M.R.A.; Sousa, B.V., E-mail: eduardopereira.eq@gmail.com [Universidade Federal de Campina Grande (UFCG), PB (Brazil). Centro de Ciencia e Tecnologia

    2016-07-01

    Sulfated metal oxides and sulfated zirconia have attracted great attention in recent years due to its high catalytic activity. The sulfated zirconia has the function of assigning the acidic material, through the formation of Bronsted acids and Lewis sites. The incorporation of sulfated zirconia in MCM-41 molecular sieve was carried out through the techniques: dry and wet. The wet process involves the use of an excess of solution on the volume of the support pores. Therefore, the concentration of the metal precursor on the support depends on the solution concentration and the pore volume of the support. In the process of incorporating by dry, the volume of the solution containing the precursor does not exceed the pore volume of the support. After either procedure, the impregnated support must be dried in order to allow the precursor compound can be converted into a catalytically active phase. This study aims to evaluate two methods of incorporation of sulfated zirconia in the mesoporous molecular sieve MCM-41. The process of merger took for wet and dry impregnation. Through the XRD patterns it was possible to identify the presence of the hexagonal structure of the molecular sieve, as well as the tetragonal and monoclinic phases of zirconia. From the spectroscopic analysis in the infrared region to the method the wet, it was possible to identify the vibrational frequencies related to the merger of sulfated zirconia in the MCM-41 structure of the molecular sieve. (author)

  8. Method of compensation spires for the detection of the diamagnetic effect in a Tokamak; Metodo de espiras de compensacion para la deteccion del efecto diamagnetico en un Tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Colunga S, S

    1990-09-15

    In this report the classical detection method of the diamagnetic effect by means of a rolled spire on the discharges chamber in the poloidal direction and the difficulties related with this are analyzed. An alternative method that increases considerably the detection sensibility of the diamagnetic effect and that for its simplicity it is quite attractive for its application to the Tokamak Novillo of the ININ is presented. (Author)

  9. Development of method to chemical separation of gallium-67 by thermal diffusion technique; Desenvolvimento de metodo para separacao quimica de galio-67 pela tecnica de difusao termica

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Patricia de Andrade

    2012-07-01

    Radioisotopes of gallium have been studied and evaluated for medical applications since 1949. Over the past 50 years {sup 67}Ga has been widely used in the diagnosis of various diseases, including acute and chronic inflammatory lesions, bacterial or sterile and several types of tumors. In Brazil 30% of clinics that provide services for Nuclear Medicine use {sup 67}Ga citrate and the demand for 67{sup G}a at IPEN-CNEN/SP is 37 GBq (1 Ci)/week. The {sup 67}Ga presents physical half-life of 3.26 days (78 hours) and decays 100% by electron capture to stable {sup 67}Zn. Its decay includes the emission of {gamma} rays with energies of 93.3 keV (37%), 184.6 keV (20.4%), 300.2 keV (16.6%) and 888 keV (26%). In the past {sup 67}Ga was produced by the reaction {sup 68}Zn (p, 2n) {sup 67}Ga at IPEN-CNEN/SP. After irradiation, the target was dissolved in concentrated HCl and the solution percolated through a cationic resin DOWEX 50W-X8, 200-400 mesh, conditioned with 10 mol L{sup -1} HCl. Zinc, nickel and copper were eluted in 10 mol L{sup -1} HCl and {sup 67}Ga 3.5 mol L{sup -1} HCl. The final product was obtained as {sup 67}Ga citrate. This work presents a new, fast, direct and efficient method for the chemical separation of 67{sup G}a by thermal diffusion (heating of the target) combined with concentrated acetic acid extraction. Purification was performed by ion exchange chromatography. Natural zinc electrodeposition was performed on nickel/copper plates as substrate and the zinc deposits were adherent to the substrate, slightly shiny and uniform. The targets were irradiated with 26 MeV protons and integrated current of 10 {mu}A.h. After irradiation, the targets were heated at 300 deg C for 2 hours and placed in contact with concentrated acetic acid for 1 hour. The average yield of extraction of {sup 67}Ga was (72 {+-} 10)%. This solution was evaporated and the residue was taken up in 0.5 mol L{sup -1} NH{sub 4}OH. The 67{sup G}a was purified on cationic resin Dowex 50WX8 in NH{sub 4}OH medium. The {sup 67}Ga recovery was (98 {+-} 2)%. This solution was evaporated and taken up in 0.1 mol L{sup -1} HCl. The chemical purity was evaluated by ICP-OES that resulted in (2 {+-} 1) {mu}g mL{sup -1} of zinc. The concentration of iron, copper and nickel was lower than the detection limits and also than the utilization limits for {sup 67}Ga. The radionuclidic purity was greater than (99.9%). This method showed to be suitable to obtain high purity {sup 67}Ga in less aggressive chemical conditions than before. (author)

  10. Covering localization, mapping and evaluation of ducts, using Pipeline Current Mapper Methods (PCM); Localizacao, mapeamento e avaliacao de revestimento de dutos, utilizando o metodo Pipeline Current Mapper (PCM)

    Energy Technology Data Exchange (ETDEWEB)

    Furquim, Antonio Jorge [ESTEIO Engenharia e Aerolevantamentos S.A., Curitiba, PR (Brazil)

    2005-07-01

    Esteio Engenharia e Aerolevantamentos S.A., together with the PETROBRAS - Petroleo Brasileiro S.A., comes accomplishing the Location, Geo positioning, Mapping and Inspection of the Coating in more than 5.000 km of pipes in several areas of the country. The works come being executed seeking the obtaining of the real position of Ducts (They-Built) and the conditions in that meets the coating of the same ones. The risings base on the method Pipeline Current Mapper (PCM), using the equipment of production of Radio detection to locate and to inspect the conditions of the coating. This work presents the results, analyses, precision, benefits and difficulties found during the execution of the surveying. (author)

  11. Evaluation of the reconstruction method and effect of partial volume in brain scintiscanning; Avaliacao do metodo de reconstrucao e efeito do volume parcial em cintilografia cerebral

    Energy Technology Data Exchange (ETDEWEB)

    Pinheiro, Monica Araujo

    2016-10-01

    Alzheimer's disease is a neurodegenerative disorder, on which occurs a progressive and irreversible destruction of neurons. According to the World Health Organization (WHO) 35.6 million people are living with dementia, being recommended that governments prioritize early diagnosis techniques. Laboratory and psychological tests for cognitive assessment are conducted and further complemented by neurological imaging from nuclear medicine exams in order to establish an accurate diagnosis. The image quality evaluation and reconstruction process effects are important tools in clinical routine. In the present work, these quality parameters were studied, and the effects of partial volume (PVE) for lesions of different sizes and geometries that are attributed to the limited resolution of the equipment. In dementia diagnosis, this effect can be confused with intake losses due to cerebral cortex atrophy. The evaluation was conducted by two phantoms of different shapes as suggested by (a) American College of Radiology (ACR) and (b) National Electrical Manufacturers Association (NEMA) for Contrast, Contrast-to-Noise Ratio (CNR) and Recovery Coefficient (RC) calculation versus lesions shape and size. Technetium-99m radionuclide was used in a local brain scintigraphy protocol, for proportions lesion to background of 2:1, 4:1, 6:1, 8:1 and 10:1. Fourteen reconstruction methods were used for each concentration applying different filters and algorithms. Before the analysis of all image properties, the conclusion is that the predominant effect is the partial volume, leading to errors of measurement of more than 80%. Furthermore, it was demonstrate that the most effective method of reconstruction is FBP with Metz filter, providing better contrast and contrast to noise ratio results. In addition, this method shows the best Recovery Coefficients correction for each lesion. The ACR phantom showed the best results assigned to a more precise reconstruction of a cylinder, which does not occur with spherical lesions in the NEMA simulator. The obtained RC values can be applied to correct the lesions quantification for different sizes and intake relations, assisting medical staff in the quantification process and an accurate diagnosis. Each Nuclear Medicine Service should establish its own RC levels to improve quality of the service provided to the population. (author)

  12. An experimental-numerical method for comparative analysis of joint prosthesis; Un metodo numerico-experimental para el analisis comparativo de protesis articulares

    Energy Technology Data Exchange (ETDEWEB)

    Claramunt, R.; Rincon, E.; Zubizarreta, V.; Ros, A.

    2001-07-01

    The difficulty that exists in the analysis of mechanical stresses in bones is high due to its complex mechanical and morphological characteristics. This complexity makes generalists modelling and conclusions derived from prototype tests very questionable. In this article a relatively simple comparative analysis systematic method that allow us to establish some behaviour differences in different kind of prosthesis is presented. The method, applicable in principle to any joint problem, is based on analysing perturbations produced in natural stress states of a bone after insertion of a joint prosthesis and combines numerical analysis using a 3-D finite element model and experimental studies based on photoelastic coating and electric extensometry. The experimental method is applied to compare two total hip prosthesis cement-free femoral stems of different philosophy. One anatomic of new generation, being of oblique setting over cancellous bone and the other madreporique of trochantero-diaphyseal support over cortical bone. (Author) 4 refs.

  13. Study of the degradation of liquid-organic radioactive wastes by electrochemical methods; Estudio de la degradacion de desechos liquidos-organicos radiactivos mediante metodos electroquimicos

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez A, J. I.

    2015-07-01

    In this study degradation studies were performed on blank samples, in which two electrochemical cells with different electrodes were used, the first is constituted by mesh electrodes Ti/Ir-Ta/Ti and the second by rod electrodes Ti/Ddb, using as reference an electrolytic medium of scintillation liquid and scintillation liquid more water, applying different potentials ranging from 1 to 25 V. After obtaining the benchmarks, the treatment was applied to samples containing organic liquid radioactive waste, in this case a short half-life radioisotope as Sulfur-35, the degradation characterization of organic compounds was performed in infrared spectrometry. (Author)

  14. Method for evaluating the applicability and application rate wastes in soil; Metodo para avaliacao da aplicabilidade e taxa de aplicacao de residuos em solo

    Energy Technology Data Exchange (ETDEWEB)

    Linhares, Monica Moreira [Partime (Brazil); Seabra, Paulo Negrais [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas

    1991-01-01

    Land treatment of refinery solid wastes has been practiced in the last few years by some PETROBRAS refineries. The biodegradation process is dynamic and complex, and incorrect monitoring may destroy the potential of the soil. Due to great differences both in terms of soils and of residues, each case must be monitored individually. We therefore developed a monitoring method for land farming systems based on the impact of the waste on indigenous soil microbial populations. The method is extremely simple, requiring only a gas chromatograph to evaluate the CO{sub 2} evolution, and can detect possible causes for low efficiency biodegradation processes. Conditions should then be altered, to ensure adequate functioning of the system.The method also allows for determination of the applicability of candidate wastes and of acceptable waste application rates in soil. (author) 2 refs., 7 figs.

  15. Volatilization mechanism of certain elements in a method of semiquantitative spectrographic analysis; Mecanismo de volatilizacion de ciertos elementos en un metodo de analisis espectrografico semicuantitativo

    Energy Technology Data Exchange (ETDEWEB)

    Diaz-Guerra, J P

    1972-07-01

    The efficiency of the compounds GeO{sub 2}, Li{sub 2}B{sub 4}O{sub 7}, Li{sub 2}CO{sub 3}, SiO{sub 2} and SrCO{sub 3} as spectrochemical buffers, in the development of a semiquantitative spectrographic method of analysis, that can be applied to the determination of 47 elements in different matrices, has been tested. It has been shown that trough the use of Li{sub 2}B{sub 4}O{sub 7} or Geo{sub 2} adequate accuracy is obtained, attaining with the latter the detection of much lower concentrations, specially for the elements Mo. Ti, V and W. In order to account for the different behaviour of these elements their volatilization mechanism has been studied. MoB{sub 2}, TiB{sub 2}, VB{sub 2}.{delta}WB and {epsilon}-WB were found, by x-ray diffraction analysis, to be reaction products in the case of mixtures with Li{sub 2}B{sub 4}O{sub 7}. (Author)

  16. Methods of Uranium Determination in solutions of Tributyl Phosphate and Kerosene; Metodos de determinacion de uranio en soluciones de fosfato de tributilo y queroseno

    Energy Technology Data Exchange (ETDEWEB)

    Petrement Eguiluz, J; Palomares Delgado, F

    1962-07-01

    A new analytical method for the determination of uranium in organic solutions of tributyl phosphate and kerosene is proposed. In this method the uranium is reectracted from the aqueous phase by reduction with cadmium in acid solution. The uranium can be determined in this solution by the usual methods. In case of very diluted solutions, a direct spectrophtometrical determination of uranium in the organic phase with dibenzoylmethane is proposed. (Author) 21 refs.

  17. Production of nano structured zinc oxide by the flame spray method; Obtencao de oxido de zinco nanoestruturado pelo metodo de aspersao de solucao em chama

    Energy Technology Data Exchange (ETDEWEB)

    Trommer, R.M.; Bergmann, C.P. [Universidade Federal do Rio Grande do Sul (LACER/PPGEM/UFRGS), Porto Alegre, RS (Brazil). Programa de Pos-graduacao em Engenharia de Minas, Metalurgica e de Materiais. Lab. de Materiais Ceramicos

    2009-07-01

    Nanostructured zinc oxide has been widely employed in several applications, mainly as antibactericidal and absorber of ultraviolet radiation (UV). The preference for a nanostructured material is associated with the different properties presented by these entities when compared to the bulk material. Thus, this work employed the flame spray technique, an alternative method with an enormous potential in nanoparticles production, to obtain ZnO powders. Basically, a precursor solution is prepared, atomized and then sprayed in the flame, where it burns and leads to the formation of particles. X-ray diffraction analysis pointed the crystalline phase zincite. By scanning electronic microscopy, it was possible to observe irregular and aggregated particles in the powder. By transmission electronic microscopy, images of the nanometric ZnO particles were obtained, being later confirmed by the single line method. (author)

  18. Metodo de quantificação de nucleotideos por HPLC-MS/MS e avaliação da atividade de analogos de sildenafil sobre fosfodiesterase

    OpenAIRE

    Raquel Lorenzetti

    2007-01-01

    Resumo: No presente trabalho foi padronizado um novo método para a dosagem da atividade de fosfodiesterase in vitro, por HPLC-MS/MS. Este novo método conseguiu apresentar exatidão, precisão, sensibilidade e rapidez nas análises; monitorando os nucleotídeos (AMP, GMP, AMPc e GMPc). O desenvolvimento de novos fármacos derivados de um protótipo aponta para a obtenção de moléculas com um melhor perfil farmacocinético ou uma melhor relação estrutura-atividade. Atualmente o sildenafil é considerad...

  19. Optical coherence tomography signal analysis: LIDAR like equation and inverse methods; Analise de sinais de tomografia por coerencia optica: equacao LIDAR e metodos de inversao

    Energy Technology Data Exchange (ETDEWEB)

    Amaral, Marcello Magri

    2012-07-01

    Optical Coherence Tomography (OCT) is based on the media backscattering properties in order to obtain tomographic images. In a similar way, LIDAR (Light Detection and Range) technique uses these properties to determine atmospheric characteristics, specially the signal extinction coefficient. Exploring this similarity allowed the application of signal inversion methods to the OCT images, allowing to construct images based in the extinction coefficient, original result until now. The goal of this work was to study, propose, develop and implement algorithms based on OCT signal inversion methodologies with the aim of determine the extinction coefficient as a function of depth. Three inversion methods were used and implemented in LABView{sup R}: slope, boundary point and optical depth. Associated errors were studied and real samples (homogeneous and stratified) were used for two and three dimension analysis. The extinction coefficient images obtained from the optical depth method were capable to differentiate air from the sample. The images were studied applying PCA and cluster analysis that established the methodology strength in determining the sample's extinction coefficient value. Moreover, the optical depth methodology was applied to study the hypothesis that there is some correlation between signal extinction coefficient and the enamel teeth demineralization during a cariogenic process. By applying this methodology, it was possible to observe the variation of the extinction coefficient as depth function and its correlation with microhardness variation, showing that in deeper layers its values tends to a healthy tooth values, behaving as the same way that the microhardness. (author)

  20. Analysis of human enamel and dentine by neutron activation analysis; Analise de esmalte e dentina de humanos pelo metodo de ativacao com neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Marco A.B. [Sao Paulo Univ., SP (Brazil). Inst. de Quimica]. E-mail: vankfire@gmail.com; Adachi, Eduardo M.; Saiki, Mitiko [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)

    2005-07-01

    Determination of trace elements in dental tissues has been of great interest to study the correlation between element composition and caries as well as food habits of individuals. In the present study dentine and enamel samples from healthy individuals were analysed by neutron activation analysis. The teeth were provided form dental clinics, and they were previously washed using purified water and acetone. Then they were dried at 40 deg C and ground in a agate mortar. The samples and element standards were irradiated with thermal neutrons at the IEA-R1 nuclear reactor. Long irradiations of 8 h under thermal neutron flux of 5x10{sup 12} n cm{sup -2} s{sup -1} were used for Ca, Na, Sr and Zn determinations. In short irradiations of 15 s and under neutron flux of 10{sup 12} n cm{sup -2} s{sup -1} the elements Mg, Mn, Na e Sr were determined. The induced gamma activities of the samples and standards were measured using a hyperpure Ge detector coupled to a gamma ray spectrometer. Elemental concentrations were calculated by comparative method. Results obtained showed that Ca, Mg and Na are present in both tissues at the level of percentages and the elements Mn, Sr and Zn at the {mu}g g{sup -1} levels. For quality control of the results the certified reference materials NIST 1400 Bone Ash and NIST 1486 Bone Meal were analysed. (author)

  1. An in vitro study of dental enamel wear by restorative materials using radiometric method; Estudo in vitro do desgaste do esmalte dental pelos materiais restauradores utilizando metodo radiometrico

    Energy Technology Data Exchange (ETDEWEB)

    Adachi, Lena Katekawa

    2000-07-01

    There is an increasing demand and interest to study the dental materials wear as well as about the abrasion effect on antagonistic teeth. Due to the fact that the existent restorative materials have no specifications about their abrasiveness, it is necessary the establishment of degrees of comparison among them to support clinical application. In this work, the radiometric method was applied to study the enamel wear caused by another enamel and by restorative materials (Ceramco II, Noritake and Finesse porcelains, Artglass and Targis). The dental enamel made radioactive by irradiation at the IEA-R1m nuclear research reactor under a thermal neutron flux was submitted to wear in a machine which allows sliding motion of an antagonistic surface in contact with this radioactive enamel. The enamel wear was evaluated by measuring beta activity of {sup 32}P transferred to water from this irradiated tooth. Results obtained indicated that dental porcelains cause pronounced enamel wear when compared with that provoked by another enamel or by resin materials. Resin materials caused less enamel wear than another enamel. Vickers microhardness data obtained for antagonistic materials showed a correlation with the wear caused to the enamel. This study allowed to conclude that the radiometric method proposed can be used satisfactorily in the evaluation of enamel wear by restorative materials. This method presents advantages due to quick responses and ease of analyses There is (author)

  2. Determination of bacterial endotoxin (pyrogen) in radiopharmaceuticals by the gel clot method. Validation; Determinacao de endotoxina bacteriana (pirogenio) em radiofarmacos pelo metodo de formacao de gel. Validacao

    Energy Technology Data Exchange (ETDEWEB)

    Fukumori, Neuza Taeko Okasaki

    2008-07-01

    Before the Limulus amebocyte lysate (LAL) test, the only available means of pirogenicity testing for parenteral drugs and medical devices was the United States Pharmacopoeia (USP) rabbit pyrogen test. Especially for radiopharmaceuticals, the LAL assay is the elective way to determine bacterial endotoxin. The aim of this work was to validate the gel clot method for some radiopharmaceuticals without measurable interference. The FDA's LALTest guideline defines interference as a condition that causes a significant difference between the endpoints of a positive water control and positive product control series using a standard endotoxin. Experiments were performed in accordance to the USP bacterial endotoxins test in the {sup 131}I- m-iodobenzylguanidine; the radioisotopes Gallium-67 and Thallium-201; the lyophilized reagents DTPA, Phytate, GHA, HSA and Colloidal Tin. The Maximum Valid Dilution (MVD) was calculated for each product based upon the clinical dose of the material and a twofold serial dilution below the MVD was performed in duplicate to detect interferences. The labeled sensitivity of the used LAL reagent was 0.125 EU mL{sup -1} (Endotoxin Units per milliliter). For validation, a dilution series was performed, a twofold dilution of control standard endotoxin (CSE) from 0.5 to 0.03 EU mL{sup -1}, to confirm the labeled sensitivity of the LAL reagent being tested in sterile and non pyrogenic water, in quadruplicate. The same dilution series was performed with the CSE and the product in the 1:100 dilution factor, in three consecutive batches of each radiopharmaceutical. The products {sup 131}I-m-iodobenzylguanidine, Gallium-67, Thallium-201, DTPA, HSA and Colloidal Tin were found compatible with the LAL test at a 1:100 dilution factor. Phytate and GHA showed some interference in the gel clot test. Other techniques to determine endotoxins as the chromogenic (color development) and the turbidimetric test (turbidity development), were also assessed to get valuable quantitative and qualitative information about the endotoxin concentration in samples. (author)

  3. Safety assessment of nuclear medicine practice using the Risk Matrix Method; Evaluaciones de seguridad de la practica de medicina nuclear utilizando el metodo de Matrices de Riesgo

    Energy Technology Data Exchange (ETDEWEB)

    Cruz, Dumenigo; Cruz, Yoanis; Soler, Karen, E-mail: cruz@orasen.co.cu [Centro Nacional de Seguridad Nuclear (CNSN), La Habana (Cuba); Guerrero, Mayka, E-mail: mayka@infomed.sld.cu [Centro de investigaciones Medico Quirurgicas (CIMEQ), La Habana (Cuba)

    2013-10-01

    This paper presents the main results from the application of the methodology of Risk Matrices in a hypothetical service / department of the Nuclear medicine that realize metabolic radiotherapy treatment and diagnostic studies with {sup 131}I and {sup 99} m Tc and {sup 18}F. We could identify major equipment failures and human errors that could potentially lead to a accident in practice. For each analyzed initiating events evaluated the frequency of occurrence, identified key existing defenses to avoid the accident and assessed the potential consequences of an accident if this comes to fruition. With this methodology we could identify which accident sequences increased risk and to propose means to reduce the risk in such cases. As a result of this work was developed the 'RMA Nuclear Medicine' computer tools that will apply this methodology in nuclear medicine services that need to do similar risk assessments.

  4. Optimization of a radiochemistry method for plutonium determination in biological samples; Optimizacion del metodo radioquimico para determinar plutonio en muestras biologicas

    Energy Technology Data Exchange (ETDEWEB)

    Cerchetti, Maria L; Arguelles, Maria G [Comision Nacional de Energia Atomica, Ezeiza (Argentina). Laboratorio de Dosimetria Personal y de Area

    2005-07-01

    Plutonium has been widely used for civilian an military activities. Nevertheless, the methods to control work exposition have not evolved in the same way, remaining as one of the major challengers for the radiological protection practice. Due to the low acceptable incorporation limit, the usual determination is based on indirect methods in urine samples. Our main objective was to optimize a technique used to monitor internal contamination of workers exposed to Plutonium isotopes. Different parameters were modified and their influence on the three steps of the method was evaluated. Those which gave the highest yield and feasibility were selected. The method involves: 1-) Sample concentration (coprecipitation); 2-) Plutonium purification; and 3-) Source preparation by electrodeposition. On the coprecipitation phase, changes on temperature and concentration of the carrier were evaluated. On the ion-exchange separation, changes on the type of the resin, elution solution for hydroxylamine (concentration and volume), length and column recycle were evaluated. Finally, on the electrodeposition phase, we modified the following: electrolytic solution, pH and time. Measures were made by liquid scintillation counting and alpha spectrometry (PIPS). We obtained the following yields: 88% for coprecipitation (at 60 C degree with 2 ml of CaHPO{sub 4}), 71% for ion-exchange (resins AG 1x8 Cl{sup -} 100-200 mesh, hydroxylamine 0.1N in HCl 0.2N as eluent, column between 4.5 and 8 cm), and 93% for electrodeposition (H{sub 2}SO{sub 4}-NH{sub 4}OH, 100 minutes and pH from 2 to 2.8). The expand uncertainty was 30% (NC 95%), the decision threshold (Lc) was 0.102 Bq/L and the minimum detectable activity was 0.218 Bq/L of urine. We obtained an optimized method to screen workers exposed to Plutonium. (author)

  5. Method for radon measurement in the subsoil in geothermal prospectus; Metodos de medicion de radon en el subsuelo en prospeccion geotermica

    Energy Technology Data Exchange (ETDEWEB)

    Balcazar G, M

    1991-02-15

    The present formless describe the technique for radon measurement in the underground, being able to be used as an additional study in the geothermal prospecting. This methodology has been developed in the National Institute of Nuclear Research of Mexico using a film of cellulose nitrate to detect those emanated alpha particles, by the Rn (222). By means of the trace account in this films its settle down the present radon levels in the underground. The present method thinks about as an alternating one to overcome in it leaves the limitations found in the development of the methodology using a radon emanometer ETR-1, of the trade mark SCINTREX. The radon detected by plastics is also an integral method of measuring in a geothermal field that avoids the problems of variations of radon to pluvial precipitations and barometric variations. These variations affect the results strongly when it is used the punctual sampler as it is the ETR-1. (Author)

  6. Obtention of the parameters of the Voigt function using the least square fit method; Obtencion de los parametros de la funcion Voigt empleando el metodo de minimos cuadrados

    Energy Technology Data Exchange (ETDEWEB)

    Flores Ll, H.; Cabral P, A.; Jimenez D, H

    1990-01-15

    The fundamental parameters of the Voigt function are determined: lorentzian wide ({gamma}{sub L}) and gaussian wide ({gamma}{sub G}) with an error for almost all the cases inferior to 1% in the intervals 0.01 {<=} {gamma}{sub L} / {gamma}{sub G} {<=}1 and 0.3 {<=} {gamma}{sub G} / {gamma}{sub L} {<=}1. This is achieved using the least square fit method with an algebraic function, being obtained a simple method to obtain the fundamental parameters of the Voigt function used in many spectroscopies. (Author)

  7. Evaluation of occupational exposure in interventionist procedures using Monte Carlo Method; Avaliacao das exposicoes dos envolvidos em procedimentos intervencionistas usando metodo Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Santos, William S.; Neves, Lucio P.; Perini, Ana P.; Caldas, Linda V.E., E-mail: williathan@yahoo.com.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Belinato, Walmir; Maia, Ana F. [Universidade Federal de Sergipe (UFS), Sao Cristovao, SE (Brazil). Departamento de Fisica

    2014-07-01

    This study presents a computational model of exposure for a patient, cardiologist and nurse in a typical scenario of cardiac interventional procedures. In this case a set of conversion coefficient (CC) for effective dose (E) in terms of kerma-area product (KAP) for all individuals involved using seven different energy spectra and eight beam projections. The CC was also calculated for the entrance skin dose (ESD) normalized to the PKA for the patient. All individuals were represented by anthropomorphic phantoms incorporated in a radiation transport code based on Monte Carlo simulation. (author)

  8. External individual monitoring: experiments and simulations using Monte Carlo Method; Monitoracao individual externa: experimentos e simulacoes com o metodo de Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Guimaraes, Carla da Costa

    2005-07-01

    In this work, we have evaluated the possibility of applying the Monte Carlo simulation technique in photon dosimetry of external individual monitoring. The GEANT4 toolkit was employed to simulate experiments with radiation monitors containing TLD-100 and CaF{sub 2}:NaCl thermoluminescent detectors. As a first step, X ray spectra were generated impinging electrons on a tungsten target. Then, the produced photon beam was filtered in a beryllium window and additional filters to obtain the radiation with desired qualities. This procedure, used to simulate radiation fields produced by a X ray tube, was validated by comparing characteristics such as half value layer, which was also experimentally measured, mean photon energy and the spectral resolution of simulated spectra with that of reference spectra established by international standards. In the construction of thermoluminescent dosimeter, two approaches for improvements have. been introduced. The first one was the inclusion of 6% of air in the composition of the CaF{sub 2}:NaCl detector due to the difference between measured and calculated values of its density. Also, comparison between simulated and experimental results showed that the self-attenuation of emitted light in the readout process of the fluorite dosimeter must be taken into account. Then, in the second approach, the light attenuation coefficient of CaF{sub 2}:NaCl compound estimated by simulation to be 2,20(25) mm{sup -1} was introduced. Conversion coefficients C{sub p} from air kerma to personal dose equivalent were calculated using a slab water phantom with polymethyl-metacrilate (PMMA) walls, for reference narrow and wide X ray spectrum series [ISO 4037-1], and also for the wide spectra implanted and used in routine at Laboratorio de Dosimetria. Simulations of backscattered radiations by PMMA slab water phantom and slab phantom of ICRU tissue-equivalent material produced very similar results. Therefore, the PMMA slab water phantom that can be easily constructed with low price can be considered a convenient practical alternative to substitute the tissue-equivalent slab. Conversion coefficients from air kerma to personal dose equivalent obtained were compared with published data. lt was found that the quantity kerma in the medium commonly used for the evaluation of conversion coefficients at depths of the order or less than 0,07 mm does not provide good results for monoenergetic photon beams with energy between 200 to 1250 keV. In this range, it is necessary to consider the absorbed dose quantity. We conclude that the GEANT4 is a suitable toolkit not only to simulate thermoluminescent dosimeters and experimental procedures employed in the routine of a dosimetry laboratory, but also to shed light upon ali the experimental results obtained in external individual monitoring that are not always expected. (author)

  9. Utilizacion del metodo de hidrolisis de los amilostatolitos para el diagnostico de resistencia al calor, la sequia y la salinidad en el tomate

    Directory of Open Access Journals (Sweden)

    Jorge A. Sánchez

    2000-01-01

    Full Text Available Se propone 5 indices de calidad que penni- ten estimar certerarnentel nivel de calidad y po- tencial productivo de una plantaci6n forestal. £1 primer indice es el de calidad general y debe uti- lizarse preferiblemente en plantaciones no ralea- das. £ste indiceproducira valores de 1.0-4.0. Valo- res cercanos a 1 serlin de plantaciones de la mas al- ta calidad. £1 segundo es el de calidad de cosecha y se basa en la cantidad de individuos presentes por ha de calidad 1 y 2. Una plantaci6n con 400 indi- viduos de calidad 1 +2 seria excelente y con menos de 200 individuos seria de mala calidad. £1 tercero es el de calidad maxima, que busca reflejar en que proporci6n la plantaci6n se aproxima al maximo numero posible de individuos de calidad 1 y de 40 cm de dap que puede contener una plantaci6n fo- festal ala cosecha; es basado en N 1=250 Y genera harvalores porcentuales, donde una plantaci6n con >90% seria excelente y 1600 trozas/ha de calidad 1+2 son excelentes y aquellas <800 trozas son inaceptables. Por ultimo se incluye el indice de calidad de productividad, que permite valorar la calidad de una plantaci6n en

  10. Studies of trace element determinations in nails by neutron activation analysis method; Estudo de elementos traco em unhas pelo metodo de analise por ativacao com neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Aguiar, Amilton Reinaldo; Saiki, Mitiko [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)

    1996-07-01

    The purpose of this work was to develop the neutron activation analysis for trace element determinations in nails in order to apply this method to the study of the cystic fibrosis disease. It was verified that the elements Al, As, Br, Ca, Cd, Cl, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Se and Zn can be determined by using short and long irradiations with thermal neutron flux from 10{sup 11} to 10{sup 13} n.cm{sup -2}.{sup -1} at the IEA-R1 nuclear research reactor. The washing solutions of triton-X100, NH{sub 4} OH and acetone were tested in order to eliminate external contaminants from the nail samples. The nail analyses of the individual fingers from both of hands showed that the samples must be collected from all the fingers from both of hands to have a representative sample. The precision and the accuracy of the results were also examined by analyzing NIES 10C Rice Flour, IUPAC Bowen's Kale and NIST 1572 Citrus Leaves reference materials. (author)

  11. Application of the Method Risk Matrix to Radiotherapy. Main Principles; Aplicacion del metodo de la matriz de riesgo a la radioterapia. Texto Principal

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-08-15

    The published fundamental principles of security, and basic international standards of security for ionizing radiation safety, contain requirements of protection for patients undergoing medical exposure. In accordance with these requirements and fulfilling its responsibility to provide for the application of these rules, the IAEA has been working intensively in the prevention of accidental exposures in radiotherapy, and this has resulted in a series of technical reports on the lessons learned from the research done in very serious events, and also in teaching materials shared for regional courses and accessible on the website for the protection of patients. The lessons learned are necessary but not sufficient, as we continue receiving information about new types of accidental exposures and not all may have been published. We need a more proactive approach, with a systematic, comprehensive and structured manner, to try to find out in advance what other errors may happen, to prevent or detect them early. Among these approaches are the method of the 'risk matrix', which by its relative simplicity can be applied to all radiotherapy service.

  12. Planetary method to measure the neutrons spectrum in lineal accelerators of medical use; Metodo planetario para medir el espectro de neutrones en aceleradores lineales de uso medico

    Energy Technology Data Exchange (ETDEWEB)

    Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico); Benites R, J. L., E-mail: fermineutron@yahoo.com [Centro Estatal de Cancerologia de Nayarit, Servicio de Seguridad Radiologica, Calzada de la Cruz 118 Sur, 63000 Tepic, Nayarit (Mexico)

    2014-08-15

    A novel procedure to measure the neutrons spectrum originated in a lineal accelerator of medical use has been developed. The method uses a passive spectrometer of Bonner spheres. The main advantage of the method is that only requires of a single shot of the accelerator. When this is used around a lineal accelerator is necessary to operate it under the same conditions so many times like the spheres that contain the spectrometer, activity that consumes enough time. The developed procedure consists on situating all the spheres of the spectrometer at the same time and to realize the reading making a single shot. With this method the photo neutrons spectrum produced by a lineal accelerator Varian ix of 15 MV to 100 cm of the isocenter was determined, with the spectrum is determined the total flow and the ambient dose equivalent. (Author)

  13. Field theory methods applied for the study of superconductivity in one-dimensional systems; Metodos de teoria de campos no estudo da supercondutividade em sistemas unidimensionais

    Energy Technology Data Exchange (ETDEWEB)

    Martins, M J

    1987-12-31

    It is shown that the Froehlich`s hamiltonian in one spatial dimension is identical to that of an exactly solvable field Theory. The spectrum of the theory is computed. A critical coupling is found above which the system becomes unstable, indicating a superconducting transition. It is also proposed and investigated a renormalizable relativistic field theory model in two space-time dimensions, with quartic self-interaction among N species of fermions, which undergoes dynamical generation of a superconducting gap and is asymptotically free. A finite temperature is introduced and, for N -> {infinity} a critical value T{sub c} is found above which the gap vanishes. (author).

  14. Method of evaluation of diagnostics reference levels in computerized tomography; Metodo de avaliacao de niveis de referencia de radiodiagnostico em tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Vega, Walter Flores

    1999-04-01

    Computerized tomography is a complex technique with several selectable exposition parameters delivering high doses to the patient. In this work it was developed a simple methodology to evaluate diagnostic reference levels in computerized tomography, using the concept of Multiple Scan Average Dose (MSAD), recently adopted by the Health Ministry. For evaluation of the MSAD, a dose distribution was obtained through a measured dose profile on the axial axis of a water phantom with thermoluminescence dosemeters, TLD-100, for different exam technique. The MSAD was evaluated hrough two distinct methods. First, it was evaluated by the integration of the dose profile of a single slice and, second, obtained by the integration on central slice of the profile of several slices. The latter is in of accordance with the ionization chamber method, suggesting to be the most practical method of dose evaluation to be applied in the diagnostic reference level assessment routine for CT, using TLDs. (author)

  15. Automatic method detection of artifacts for control of tomographic uniformity on SPECT; Metodo automatico de dteccion de artefactos para el control de la uniformidad tomografica en SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Reynes Llompart, G.; Puchal, R.

    2013-07-01

    The objective of this work is the find an automatic method for the detection and classification of artifacts produced in tomographic uniformity, extracting the characteristics necessary to apply a classification algorithm using pattern recognition techniques. The method has been trained and validated with synthetic images and tested with real images. (Author)

  16. Vasoactive intestinal peptide (VIP) labelling with iodine-131 by direct method; Marcacao do peptideo intestinal vasoativo (VIP) com iodo-131 por metodo direto

    Energy Technology Data Exchange (ETDEWEB)

    Colturato, M.T.; Silva, C.P.G. da; Araujo, E.B. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil). Centro de Radiofarmacia

    2002-07-01

    The Vasoactive Intestinal Peptide (VIP) is a 28-amino acid polypeptide with a great numbers of receptors in tumoral cells, including adenocarcinomas and pancreatic and colon carcinomas. The VIP molecule contains two tyrosine residues, in positions 10 and 22, that are theoretically equally susceptible to iodination, The VIP was labeled with 131-iodine by direct method using Iodogen as oxidant agent: 15.03 mmol VIP + 0.10 nmol KI + [{sup 131} I]NaI + 13.9 mmol Iodogen; the final volume was adjust to 100 {mu}L using 0.2 M phosphate buffer, pH 7.5 and the reaction proceed with stirring for 30 minutes at room temperature. The radiochemical purity was determined by electrophoresis (Whatman 1MM paper; 0.05 M barbital buffer; pH 8.6; 150 V; 40 minutes) that indicates low percent of free 131-iodine. The high performance liquid chromatography (HPLC) system using RPC{sup 18}, 10 {mu}m, 4 x 250mm column, was able to separate the different radiochemical species, only when an isocratic mixture of acetonitrile: 0.1% trifluoroacetic acid (27:73) was used, with 0.5 mL/min. flux. (author)

  17. Protocolo Nacional para la Evaluacion de Disturbios en Suelos Forestales; Volumen II: Metodos complementarios, estadística y recoleccion de datos

    Science.gov (United States)

    Deborah S. Page-Dumroese; Ann M. Abbott; Thomas M. Rice

    2013-01-01

    Este documento-El Volumen II: Métodos complementarios, estadística y recolección de datos- define las bases, los métodos estadísticos y de almacenamiento de datos de un Protocolo Nacional para la Evaluación de Disturbios en Suelos Forestales. Esta guía técnica proporciona las bases de un método consistente, con definiciones comunes, para generar datos de alta calidad,...

  18. Dating of Chichen Itza ceramics by the method of thermoluminescence; Datacion de ceramica de Chichen Itza por el metodo de termoluminiscencia

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez M, P.R.; Mendoza A, D.; Cuapio O, L.A. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Ramirez L, A.; Schaaf, P. [Instituto de Geofisica-UNAM, 04510 Mexico D.F. (Mexico); Chung, H. [Dept. of Anthropology, Duksung University, Seoul (Korea, Republic of); FFL-UNAM, 04510 Mexico D.F. (Mexico)

    2005-07-01

    In this work we present some results about thermoluminescent dating of some archaeological ceramic samples belonging to Chichen Itza, Yucatan, Mexico: CH11, CH13, CH14 and CH15. The analysis was realized using the fine grained mode in a Daybreak model 1100 reader Tl System. The radioisotopes that contribute in the accumulate annual dose in ceramic samples ({sup 40} K, {sup 238} U, {sup 232} Th) were determined by means of techniques such as Energy Dispersive X-ray Spectroscopy (EDS) and Neutron Activation Analysis (NAA), while the artificial irradiation of samples was carried out with a {sup 90} Sr source beta radiation. The resulting mean CH11 ceramic sample was 934 {+-}45 years old, CH13 was 465 {+-} 26, CH14 was 888 {+-} 34 and CH15 was 867 {+-} 42. These results are in agreement with results obtained through other methods. (Author)

  19. Cuantificacion de huevo en fideos secos según metodo electroforético (SDS PAGUE) Quantification of egg in dried noodles by electrophoretic methods (SDS PAGE)

    OpenAIRE

    LB López; K Cellerino; MJ Binaghi; MS Giacomino; ME Valencia

    2011-01-01

    La cuantificación de huevo en fideos secos elaborados con harina y agregado de huevo. Se analizaron 6 sistemas modelos (SM) de fideos que contenían 0,0; 1,0; 2,5; 4,0; 6,0 y 8,0% de huevo en polvo. Se extrajeron proteínas totales con un buffer que contiene dodecilsulfato de sodio (SDS) y 2-Mercaptoetanol y se realizó electroforesis en gel de poliacrilamida con SDS. Se establecieron las relaciones de las áreas de los picos de los densitogramas (de huevo y de trigo) que permiten una correcta cu...

  20. Methods for the control of NOx and particles in the combustion; Metodos para el control de NOx y particulas en la combustion

    Energy Technology Data Exchange (ETDEWEB)

    Romo Millares, Cesar A. [Instituto de Investigaciones Electrica, Cuernavaca (Mexico)

    1996-12-31

    This present the techniques and equipment of control of transmissions for thermoelectric power stations appear that have mayor possibilities of being considered in the future immediate within the national energetic panorama and the frame established by the environmental normative. The subject polluting compounds to overhaul are oxides of nonburned nitrogen and particles [Espanol] Se presentan las tecnicas y equipos de control de emisiones para centrales termoelectricas que tienen mayores posibilidades de ser consideradas en el futuro inmediato dentro del panorama energetico nacional y el marco establecido por la normatividad ambiental. Los compuestos contaminantes sujetos a revision son los oxidos de nitrogeno y las particulas inquemadas

  1. Synthesis and characterization photocatalyst of titanium oxide obtained by the Pechini; Sintese e caracterizacao fotocatalitica do oxido de titanio obtido pelo Metodo Pechini

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, P.C.; Costa, A.C.F.M.; Lira, H.L. [Universidade Federal de Campina Grande (UFCG), PB (Brazil). Departamento de Engenharia de Materiais; Sasaki, J.M. [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Departamento de Fisica; Santos, S.K., E-mail: pollyanacae@yahoo.com.br [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Departamento de Engenharia Quimica

    2011-07-01

    The photocatalysis using TiO{sub 2} semiconductor has shown great efficiency in the treatment of toxic pollutants and non-biodegradable materials, commonly present in air and domestic and industrial effluents. Thus, the aim of this work is to study the evaluation of photocatalytic activity of TiO{sub 2} samples synthesized by the Pechini method at a ratio of citric acid / metal cation of 2:1 and 4:1. The synthesized samples were characterized by X-ray diffraction, quantification of phases using the Rietveld method of refinement of the structure and after analyzed in photocatalytic bench tests using methyl red dye. The results showed that in a 2:1 ratio, the sample resulted in the formation of 100% of anatase phase, while in the 4:1 ratio sample showed 73.51% of anatase phase and 10.5% of rutile phase. The 4:1 sample showed the best performance discoloring over 70% of the dye for a period close to 24h. (author)

  2. Torpedo Base - a new method for installation of a conductor casing; Base Torpedo - um novo metodo para instalacao do revestimento condutor

    Energy Technology Data Exchange (ETDEWEB)

    Nogueira, Emmanuel Franco; Borges, Alexandre Thomaz [PETROBRAS. E and P Engenharia de Producao. Gerencia de Perfuracao e Operacoes Especiais (Brazil)], e-mails: efranco@petrobras.com.br, atborges@petrobras.com.br; Medeiros Junior, Cipriano Jose de [PETROBRAS. Engenharia. Gerencia de Geociencias (Brazil)], e-mail: cipri.intec@petrobras.com.br; Machado, Rogerio Diniz; Souza, Ebenezer Viana de [PETROBRAS. E and P - SERV. Gerencia de Ancoragem (Brazil)], e-mail: rogeriodm@petrobras.com.br, ebnezer_souza@petrobras.com.br

    2008-12-15

    In the last years, PETROBRAS has been optimizing and reducing the cost of the mooring systems through the use of torpedo anchors. It consists of a tubular pile with heavy weight ballast, installed by a process that uses the energy generated by the free fall of the pile from a supply vessel. It is a low cost anchoring concept, with simple fabrication and installation. More than two hundred torpedo anchors were installed offshore Brazil in the last four years. Based on the success of the torpedo anchors for mooring purposes PETROBRAS Exploration and Production department decided to employ the same idea for installing the conductor casing. The benefit was that this installation could be accomplished from an anchor-handling vessel saving important rig time. Another advantage with this installation method is a better foundation provided since no soil is removed during this process. The paper will provide an overview of PETROBRAS Torpedo Base experience in the Albacora Leste field as well as a few other applications of this technology for the production side. After the final installation of two prototypes in the Albacora Leste Field, in Campos Basin, at the end of 2004, the Torpedo Base project was approved by the clients and by PETROBRAS's technological area, having its acquisition requested by five assets (management areas responsible for oil fields located in that basin), in a total of 18 Torpedo Base. The difficulties related to the hiring of services and logistics faced in order to make the installation of the equipment feasible made the E and P technological area to choose to monitor the acquisition and installation of these 18 bases, so as to ensure a smooth transition between the project authors and the technicians in charge of operation of the equipment, ensuring, therefore, the consolidation of the technology. This paper reports PETROBRAS's experience with Torpedo Bases during the installation of these 18 bases in several fields in Campos Basin, throughout almost two years. There shall be presented the problems faced, solutions for them and improvements implemented aiming at optimizing not only the equipment but also its installation process. (author)

  3. Methods for the control of NOx and particles in the combustion; Metodos para el control de NOx y particulas en la combustion

    Energy Technology Data Exchange (ETDEWEB)

    Romo Millares, Cesar A [Instituto de Investigaciones Electrica, Cuernavaca (Mexico)

    1997-12-31

    This present the techniques and equipment of control of transmissions for thermoelectric power stations appear that have mayor possibilities of being considered in the future immediate within the national energetic panorama and the frame established by the environmental normative. The subject polluting compounds to overhaul are oxides of nonburned nitrogen and particles [Espanol] Se presentan las tecnicas y equipos de control de emisiones para centrales termoelectricas que tienen mayores posibilidades de ser consideradas en el futuro inmediato dentro del panorama energetico nacional y el marco establecido por la normatividad ambiental. Los compuestos contaminantes sujetos a revision son los oxidos de nitrogeno y las particulas inquemadas

  4. Electret ionization chamber: a new method for detection and dosimetry of thermal neutrons; Camara de ionizacao de eletretos: um novo metodo para deteccao e dosimetria de neutrons termicos

    Energy Technology Data Exchange (ETDEWEB)

    Ghilardi, A J.P.

    1988-12-31

    An electret ionization chamber with boron coated walls is presented as a new method for detecting thermal neutrons. The efficiency of electret ionization chambers with different wall materials for the external electrode was inferred from the results. Detection of slow neutrons with discrimination against the detection of {gamma}-rays and energetic neutrons was shown to depend on the selection of these materials. The charge stability over a long period of time and the charge decay owing to natural radiation were also studied. Numerical analysis was developed by the use of a micro-computer PC-XT. Both the experimental and numerical results show that the sensitivity of the electret ionization chamber for detection of thermal neutrons is comparable with that of the BF{sub 3} ionization chamber and that new technologies for deposition of the boron layer will produce higher efficiency detectors. (author). 102 refs, 32 fig, 10 tabs.

  5. Error Estimation and Accuracy Improvements in Nodal Transport Methods; Estimacion de Errores y Aumento de la Precision en Metodos Nodales de Transporte

    Energy Technology Data Exchange (ETDEWEB)

    Zamonsky, O M [Comision Nacional de Energia Atomica, Centro Atomico Bariloche (Argentina)

    2000-07-01

    The accuracy of the solutions produced by the Discrete Ordinates neutron transport nodal methods is analyzed.The obtained new numerical methodologies increase the accuracy of the analyzed scheems and give a POSTERIORI error estimators. The accuracy improvement is obtained with new equations that make the numerical procedure free of truncation errors and proposing spatial reconstructions of the angular fluxes that are more accurate than those used until present. An a POSTERIORI error estimator is rigurously obtained for one dimensional systems that, in certain type of problems, allows to quantify the accuracy of the solutions. From comparisons with the one dimensional results, an a POSTERIORI error estimator is also obtained for multidimensional systems. LOCAL indicators, which quantify the spatial distribution of the errors, are obtained by the decomposition of the menctioned estimators. This makes the proposed methodology suitable to perform adaptive calculations. Some numerical examples are presented to validate the theoretical developements and to illustrate the ranges where the proposed approximations are valid.

  6. Determination of the fast neutrons spectra by the Elastic scattering method (n, p); Determinacion del espectro de neutrones rapidos por el metodo de la dispersion elastica (n, p)

    Energy Technology Data Exchange (ETDEWEB)

    Elizalde D, J

    1973-07-01

    This work consists in determining the fast neutron spectra emitted by a Pu-Be isotopic source. The implemented technique is based in the spectrometry (n, p). This consists in making to fall on a fast neutrons beams (polyenergetic) over a thin film of hydrogenated material, detecting the spectra of emitted protons at a fix angle. The polyethylene film and the used solid state detector are inside of a vacuum chamber. The detector is placed at 30 degree with respect to direction of the incident neutrons beam. The protons spectra is stored in a multichannel. the energy is obtained with the prior calibration of the system. The data processing involves the transformation of the protons spectra observed at the falling on neutrons spectra over the film. The energy of the neutrons is related with that of the protons, according to the collision kinematical equations. The cross section of elastic collision of the neutrons with the hydrogen atoms is obtained from literature. Applying these relations to the observed spectra it is obtained the falling on neutron spectra over the film. (Author)

  7. Statistics of electron multiplication in a multiplier phototube; Iterative method; Estadistica de la multiplicacion de electrones en un fotomultiplicador: Metodos iterativos

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz, J F; Grau, A

    1985-07-01

    In the present paper an iterative method is applied to study the variation of dynode response in the multiplier phototube. Three different situation are considered that correspond to the following ways of electronic incidence on the first dynode: incidence of exactly one electron, incidence of exactly r electrons and incidence of an average r electrons. The responses are given for a number of steps between 1 and 5, and for values of the multiplication factor of 2.1, 2.5, 3 and 5. We study also the variance, the skewness and the excess of jurtosis for different multiplication factors. (Author) 11 refs.

  8. Determination of Sn in 99{sup m}Tc Radiopharmaceutical Kits by Polarographic Methods; Determinacion de Estano en Radiofarmacos de 99{sup m}Tc mediante Metodos Polarograficos

    Energy Technology Data Exchange (ETDEWEB)

    Castro, M; Cruz, J; Sanchez, M

    2009-07-01

    Kits of 99{sup m}Tc radiopharmaceuticals are used in nuclear medicine for diagnosis of different diseases. Sn (II) is one of the essential components in their formulations, which is used for reduction 99{sup m}Tc-pertechnetate in cold kits for on-site preparation 99{sup m}Tc-pertechnetate radiopharmaceuticals. Usually, these cold kits contain different additives (complexing agents, antioxidants, buffers, etc.) and the amount of Sn (II) varies from kit to kit. The determination of Sn in these products is essential in assessing their quality. We report here the development of a new polarographic method for the determination of Sn (II) and total Sn in representative radiopharmaceuticals kits (for the content of Sn and chemical composition) produced at the Center of Isotopes of Cuba (CENTIS). These methods were validated by analysis of variance and recovery techniques. From the results of the validation, the characteristic functions of uncertainties and fits are considered for the established methods, which give the necessary evidences to demonstrate the usefulness of these methods according to the current trends in Analytical Chemistry. This work provides practical results of great importance for CENTIS. After the speciation of Sn in the MAG3 radiopharmaceuticals kit is inferred that the production process is affected by uncontrolled factors that influence in the product stability, which demonstrates the necessity for analytical tools for the characterization of products and processes. (Author) 57 refs.

  9. Synthesis and characterization of NiO nanoparticles by Pechini method; Sintese e caracterizacao de nanoparticulas de NiO pelo metodo Pechini

    Energy Technology Data Exchange (ETDEWEB)

    Nascimento, A; Ribeiro, M A; Costa, A C.F.M.; Gama, L [Universidade Federal de Campina Grande (UFCG), PB (Brazil). Dept. de Engenharia de Materiais; Bernardi, M I.B. [Universidade de Sao Paulo (IFSC/USP), Sao Carlos, SP (Brazil). Inst. de Fisica

    2009-07-01

    In recent years, ultrafine magnetic particles of NiO have attracting the attention because of its unknown behavior, enormous scientific potential and technological application. Some of its more important properties are accented magnetic moments, double dynamic exchange, quantization of wave of spin and etc. In this context, this work has for objective to synthesize and to characterize nanoparticles of NiO for the Pechini method. The powder was analyzed by X-rays diffraction. The results of scanning electron microscopy, adsorption of nitrogen. The analysis of X-rays diffraction of the sample showed single-phase peaks of NiO, with crystallite size close to 38 nm. The surface area was 6.44 m{sup 2}/g. The image from scanning electron microscopy shows soft homogeneous agglomerates. The Pechini synthesis was efficient in the production of powders of NiO nano metrics and single-phase. (author)

  10. Validation of a method to determine methylmercury in fish tissues using gas chromatography; Validacion de un metodo para determinar metilmercurio en tejido de pescado por cromatografia de gases

    Energy Technology Data Exchange (ETDEWEB)

    Vega Bolannos, Luisa O; Arias Verdes, Jose A; Beltran Llerandi, Gilberto; Castro Diaz, Odalys; Moreno Tellez, Olga L [Instituto de Nutricion e Higiene de los Alimentos, La Habana (Cuba)

    2000-07-01

    We validated a method to determine methylmercury in fish tissues using gas chromatography with an electron capture detector as described by the Association of Official Analytical Chemist (AOAC) International. The linear curve range was 0.02 to 1 g/ml and linear correlation coefficient was 0.9979. A 1 mg/kg methylmercury-contaminated fish sample was analyzed 20 times to determine repeatability of the method. The quantification limit was 0.16 mg/kg and detection limit was 0.06 ppm. Fish samples contaminated with 0.2 to 10 mg/kg methylmercury showed recovery indexes from 94.66 to 108.8%.

  11. Measurements with a Pulsed and Modulated Source in a Reactor; Mesures au Moyen d'une Source Pulsee et Modulee dans un Reacteur; Izmereniya v reaktore s pomoshch'yu impul'snogo i moduliruemogo is tochnika; Mediciones Efectuadas en Reactor con una Fuente Pulsada y Modulada

    Energy Technology Data Exchange (ETDEWEB)

    Rotter, W. [Centre d' Etude de l' Energie Nucleaire, Mol (Belgium)

    1965-10-15

    a digital computer [French] Un generateur dont le debit neutronique est variable selon une fonction du temps quelconque a ete mis au point par les Laboratoires de recherches Philips. Son utilite pratique dans le domaine de la physique des reacteurs a ete demontree par une serie de mesures effectuees dans le reacteur BRO2 a fotat sous-critique. Sa bonne stabilite, la possibilite de faire varier brusquement l'intensite neutronique, de puiser le debit ou de le moduler sinusoldalement, rend ce generateur tres souple. Il permet de determiner la reactivite ({rho} = {Delta}k/{beta}) et le temps de vie des neutrons ( Script-Small-L /{beta}) d'apres differentes methodes independantes. Une comparaison exacte de ces methodes est possible puisqu'elles peuvent etre employees sans modifier les conditions de mesure. On a determine: a) {rho} sur la base des neutrons retardes, par une reduction instantanee du debit de neutrons; b) {rho} sur la base des neutrons instantanes par des bouffees de neutrons; c) Script-Small-L /{beta} par combinaison de a) et b) pour 0,5 $ < {rho} <2 $; d) Script-Small-L /{beta} sur la base de la fonction de transfert du reacteur pour une source modulee. Les fonctions de transfert pour un oscillateur de reactivite et pour une source modulee sinusoldalement sont discutees. Il est montre que la mesure de Script-Small-L /{beta} est possible pour 0,1 $ < {rho} < 10 $ en utilisant une source modulee. La meme methode fournit aussi la reactivite a l'aide du rapport des neutrons instantanes aux neutrons retardes pour une frequence optimale, pratiquement independamment des donnees relatives aux neutrons retardes et de la valeur de f Script-Small-L /{beta}. Par accumulation d'un grand nombre de cycles dans l'analyseur multicanal, la statistique peut etre amelioree pour chaque methode. Le debit du generateur etant bien sinusoiedal, la reponse du reacteur peut etre integree sur chaque quart d'une periode, etant donne que la chafhe de mesure est pilotee par le

  12. Determinação e padronização da vitamina E e seus isomeros : comparação entre o metodo de cromatografia liquida de alta eficiencia (CLAE) e o metodo espectrofotometrico por redução de ions cupricos

    OpenAIRE

    Andrea Scabora Boix Caro

    2002-01-01

    Resumo: A presente Tese visou estudar a determinação da vitamina E, estabelecendo uma comparação entre o método clássico modificado com um outro método de determinação, a cromatografia líquida de alta eficiência (CLAE).Para efeito de comparação foram utilizados cinco tipos de amostras diferentes: suplementos vitamínicos, óleos vegetais, DDOS, farinha de germe de trigo e fígados liofilizados de ratos. Os resultados encontrados nos métodos avaliados diferiram quanto ao tipo de isômero encontrad...

  13. Absorption and scattering coefficients estimation in two-dimensional participating media using the generalized maximum entropy and Levenberg-Marquardt methods; Estimacion del coeficiente de absorcion y dispersion en medios participantes bidimensionales utilizando el metodo de maxima entropia generalizada y el metodo Levenberg-Marquardt

    Energy Technology Data Exchange (ETDEWEB)

    Berrocal T, Mariella J. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Programa de Engenharia Nuclear]|[Universidad Nacional de Ingenieria, Lima (Peru); Roberty, Nilson C. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Programa de Engenharia Nuclear; Silva Neto, Antonio J. [Universidade do Estado, Nova Friburgo, RJ (Brazil). Instituto Politecnico. Dept. de Engenharia Mecanica e Energia]|[Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Programa de Engenharia Nuclear

    2002-07-01

    The solution of inverse problems in participating media where there is emission, absorption and dispersion of the radiation possesses several applications in engineering and medicine. The objective of this work is to estimative the coefficients of absorption and dispersion in two-dimensional heterogeneous participating media, using in independent form the Generalized Maximum Entropy and Levenberg Marquardt methods. Both methods are based on the solution of the direct problem that is modeled by the Boltzmann equation in cartesian geometry. Some cases testes are presented. (author)

  14. Blind method of clustering for the evaluation of the dose received by personnel in two methods of administration of radiopharmaceuticals; Metodo ciego de clusterizacion para la evaluacion de la dosis recibida por el personal en dos metodos de administracion de radioformacos

    Energy Technology Data Exchange (ETDEWEB)

    VerdeVelasco, J. M.; Gonzalez Gonzalez, M.; Montes Fuentes, C.; Verde Velasco, J.; Gonzalez Blanco, F. J.; Ramos Pacho, J. A.

    2013-07-01

    The difficulty for the injection of drugs marked with radioactive isotopes while syringe is located within the lead protector does that in many cases staff do it chooses to use the syringe outside the lead protector, increasing therefore the dose of radiation received. In our service raises the possibility of using a different methodology, channeling a pathway through a catheter, which allows administer, in all cases, with the syringe within the lead guard. We will check if significant differences can be seen both in the dose absorbed by the staff as in the time it takes to perform the administration of the drug using the method proposed compared injection without guard. (Author)

  15. Indirect Determination of Half-Lives of Short-Lived Fission Gases Using a Gas Flow Method; Determination Indirecte des Courtes PeRiodes de Produits de Fission Gazeux, par une Methode a Courant Gazeux; 041a 041e 0421 0412 0415 041d 041d 041e 0415 041e 041f 0420 0415 0414 0415 041b 0415 041d 0418 0415 041f 0415 0420 0418 041e 0414 041e 0412 041f 041e 041b 0423 0420 0410 0421 041f 0410 0414 0410 041a 041e 0420 041e 0422 041a 041e 0416 0418 0412 0423 0429 0418 0425 0413 0410 0417 041e - 041e 0411 0420 0410 0417 041d 042b 0425 041f 0420 041e 0414 0423 041a 0422 041e 0412 0414 0415 041b 0415 041d 0418 042f 0421 0418 0421 041f 041e 041b 042c 0417 041e 0412 0410 041d 0418 0415 041c 041c 0415 0422 041e 0414 041e 0412 0413 0410 0417 041e 0412 041e 0413 041e 041f 041e 0422 041e 041a 0410 ; Determinacion Indirecta del T 1/2 de los Cases de Fision de Periodo Corto por un Metodo de Circulacion

    Energy Technology Data Exchange (ETDEWEB)

    Patzelt, P.; Herrmann, G. [Institut fuer Anorganische Chemie und Kernchemie der Universitaet Mainz, Mainz, Federal Republic of Germany (Germany)

    1965-07-15

    decroissance des pics gamma appropriees. Les chiffres indiques representent les valeurs moyennes d'un certain nombre d'experiences et resultent d'un mode de ponderation tel que W{sub i} Tilde-Operator 1/o{sup 2}. Tous les calculs ont ete effectues au centre d'ordinateurs de l'Universite de Mayence. (author) [Spanish] Dado que el estudio de la distribucion de las cafgas en la fision nuclear requiere la determinacion de los rendimientos primatios de los diferentes productos de fision, que por lo general son de periodo corto o derivan de precursores de periodo corto, es preciso poder llevar a cabo separaciones muy rapidas y eficaces de los eslabones contiguos de una cadena de fision. Aprovechando el poder de emanacion sumamente elevado de ciertos compuestos de uranio, se pueden practicar con gran facilidad separaciones de los gases en mas de una docena de cadenas de productos de fision. Pero el calculo de los rendimientos y del poder de emanacion efectivo de blancos en forma de capas gruesas pueden resultar considerablemente afectados por los datos relativos al periodo de los gases. En consecuencia, los autores han determinado con gran precision los periodos de los isotopos {sup 93}Kr y {sup 131}Xe a {sup 143}Xe aplicando un metodo basado en la velocidad de circulacion de estos gases, junto con una tecnica perfeccionada de carga de electrodos. Efectuaron mediciones basadas en la cantidad de productos activos de desintegracion de periodo largo depositada en los electrodos. La velocidad de circulacion, el tiempo de irradiacion y de enfriamiento, asi como los aparatos de recuento se escogieron de forma que facilitaba grandemente la medicion de cada uno de los productos descendientes. En algunos casos, fue indispensable, por razones de selectividad radioquimica, proceder a separaciones. Los resultados obtenidos son: {sup 89}Kr, 3.11 {+-} 0.06 min: {sup 90}Kr, 32.1 {+-} 0.8 s; {sup 91}Kr, 8.36 {+-} 0.15 s; {sup 92}Kr, 1,92 {+-} 0.07 s; {sup 93}Kr, 1.17 {+-} 0.04 s; {sup 137}Xe, 3

  16. Responsabilità giuridica e scienze sperimentali sul vivente

    Directory of Open Access Journals (Sweden)

    Patrick Nerhot

    2017-12-01

    Full Text Available SOMMARIO: 1. Il "vivente": inoperosità dei concetti della filosofia profana dei Lumi - 2. La ricerca-costruzione di una infinita-fine - 3. Le scienze "sperimentali" come la non distinzione tra "causa" e "effetto" - 4. La nuova questione di metodo posta al "vivente" - 5. La sfida di una etica come adeguazione tra etica e metodo.

  17. Construction of the Tangent to a Cycloid Proposed by Wallis and Fermat

    Directory of Open Access Journals (Sweden)

    Loredana Biacino

    2017-02-01

    Full Text Available In this paper some methods used in the XVII century for the construction of the tangents to a cycloid in a point are exposed: the kinematical method employed by Roberval, the classical geometrical  method used by Wallis and the Fermat’s construction as a consequence of his tangents method. Le Costruzioni della Tangente alla Cicloide Proposte da Wallis e da Fermat In questo lavoro sono esposti vari metodi in uso nel ‘600 per la costruzione della tangente ad una cicloide in un suo punto: il metodo cinematico impiegato da Roberval, il metodo geometrico classico usato dal Wallis e la costruzione di Fermat come conseguenza del suo metodo delle tangenti. Parole Chiave: Cicloide, Tangente ad una curva, Metodo cinematico delle tangenti, Metodo delle tangenti di Fermat.

  18. Desenvolvimento e validação de metodos para a determinação de antimicrobianos em leite e farmacos usando a cromatografia liquida de alta eficiencia e eletroforese capilar

    OpenAIRE

    Monica Cecilia Vargas Mamani

    2007-01-01

    Resumo: Antimicrobianos são largamente empregados na medicina veterinária e resíduos destes podem permanecer nos alimentos de origem animal, acima de valores considerados seguros, quando não são respeitadas as boas práticas veterinárias. O objetivo deste trabalho foi o desenvolvimento e validação de métodos para a determinação de tetraciclinas, sulfonamidas, cloranfenicol e fluoroquinolonas em fármacos usando a eletroforese capilar (CE), assim como método multiresíduos para a determinação de ...

  19. Origin identification for Cantona, Puebla, obsidians by the analysis method of neutron activation (NAA); Identificacion de procedencia para obsidianas de Cantona, Puebla, por el metodo de analisis por activacion neutronica (AAN)

    Energy Technology Data Exchange (ETDEWEB)

    Tellez N, A. L.

    2013-07-01

    There are tests that most of the obsidian worked in the workshops of Cantona, Puebla, is coming from the mineral deposits of Oyameles-Zaragoza, but also has been detected obsidian that macroscopically belongs to other mineral deposits. The present work has as purpose to determine the provenance of an obsidian sample obtained in the Cantona Site to know if there was the presence of obsidian of other mineral deposits. For the study the neutron activation analysis was used to identify the presence of other deposits. An explanation on the treatment to the selected pieces is included, the preparation of the same ones for its irradiation in the nuclear reactor, the counting and statistical study of the results. Finally the results of the selected samples are presented, indicating their origin places, that time comes and the interpretation of the results is given. (Author)

  20. Radioimmunoassay method for measurement of plasma androstenedione. Its validation in ovulatory women and in patients with polycystic ovarian syndrome; Metodo de radioimunoensaio para medida da androstenediona plasmatica. Validacao em mulheres ovulatorias e com sindrome dos ovarios policisticos

    Energy Technology Data Exchange (ETDEWEB)

    Vilanova Socorro Veras, Maria do; Silva e Rosa, Alzira Amelia; Moura, Marcos Dias de; Ferriano, Rui Alberto; Sa, Marcos Felipe Silva de [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Faculdade de Medicina

    1995-01-01

    The present paper has as objective the standardization of a radioimmunoassay method for measurement of androstenedione. Ethyl ether was used for plasma extraction. The sensitivity of the method was 6,8 pg/tube; the reproducibility (inter assay error) was 15,6%; the precision (intrassay error) was 5,2%. As biological control, 20 ovulatory women showed median plasma values of 1250 pg/ml and 24 women with polycystic ovary syndrome presented median plasma values of 2.037 pg/ml. (author). 6 refs., 2 figs., 1 tab.

  1. Continuous and discreet methods in the aggregation and des fuzzy stages of a diffuse controller of neutron power; Metodos continuo y discreto en las etapas de agregacion y desdifusificacion de un controlador disfuso de potencia neutronica

    Energy Technology Data Exchange (ETDEWEB)

    Najera H, M.C.; Benitez R, J.S. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2003-07-01

    The results of a comparative study are presented of: to) A denominated diffuse controller 'exact', designed by means of an innovative method that determines analytically so much the group of exit resultant in the aggregation stage like the de fuzzy process, and b) a diffuse controller denominated 'discreet' based on the discretization of the variable of having left as much for the aggregation as for the de fuzzy. These stages incorporated to the control algorithms whose objective is the ascent and regulation of the neutron power, carrying out an analysis of its performance. (Author)

  2. Optimization of the obtaining method of CaSO{sub 4}: Dy + Ptfe dosimeters; Optimizacion del metodo de obtencion de dosimetros de CaSO{sub 4}: Dy + PTFE

    Energy Technology Data Exchange (ETDEWEB)

    Galicia A, J.; Rioja Ch, J.; Torijano C, E.; Azorin N, J., E-mail: blink19871@hotmail.com [Universidad Autonoma Metropolitana, Unidad Iztapalapa, Av. San Rafael Atlixco 186, Col. Vicentina, 09340 Mexico D. F. (Mexico)

    2012-10-15

    This work contain the obtained results of studying the response when irradiating to different dose of X-rays, dosimeters of CaSO{sub 4}: Dy + Ptfe using different lapses of time in their preparation (a lot of selected dosimeters of an elaboration process of 3 days and another of an elaboration process of 2 hours). For the elaboration of the powdered material, the evaporation method was used; the irradiation were carried out in a lineal accelerator Elekta Synergy property of the National Medical Center, 20 de November. The similarities and differences are shown among the two dosimeters lots together with an analysis of the shine curves and of calibration selecting those that presented a better behaviour and a more rea liable response. (Author)

  3. Contents evaluation of some essential and toxic elements in children and elders diet by neutron activation analysis; Avaliacao do conteudo de alguns elementos essenciais e toxicos em dietas de criancas e idosos pelo metodo de analise por ativacao com neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Maihara, Vera Akiko

    1996-12-31

    Essential and toxic elements in the 19 diet samples from pre-school children and 23 diet samples from elderly people, have been determined by neutron activation analysis. The diet samples were collected by duplicate portion method. A radiochemical separation procedure was developed and applied for determining Cd, Co, Cr, Fe, Mo, Sb, U, Th, W and Zn, based on retention of these elements in a Chelex-100 resin. In the case of As and Se, the procedure was based on retention in inorganic exchanger TDO (tin dioxide). The contents of proteins, lipids and carbohydrates were also analysed. The results have been presented and discussed 135 refs., 29 figs., 36 tabs.

  4. Analytical Evaluation to Determine Selected PAHs in a Contaminated Soil With Type II Fuel; Metodo Optimizado de Extraccion por Ultrasonidos para la Determinacion de PAHs Seleccionados en un Suelo Contaminado con Fuel de Tipo II

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Alonso, S.; Perez Pastor, R. M.; Sevillano Castano, M. L.; Garcia Frutos, F. J.

    2010-10-21

    A study on the optimization of an ultrasonic extraction method for selected PAHs determination in soil contaminated by type II fuel and by using HPLC with fluorescence detector is presented. The main objective was optimize the analytical procedure, minimizing the volume of solvent and analysis time and avoiding possible loss by evaporation. This work was carried out as part of a project that investigated a remediation process of agricultural land affected by an accidental spillage of fuel (Plan Nacional I + D + i, CTM2007-64 537). The paper is structured as: Optimization of wavelengths in the chromatographic conditions to improve resolution in the analysis of fuel samples. Optimization of the main parameters affecting in the extraction process by sonication. Comparison of results with those obtained by accelerated solvent extraction. (Author) 3 refs.

  5. Study of the calcination temperature in samples of calcium phosphate synthesized by the method of direct way; Estudo da temperatura de calcinacao em amostras de fosfatos de calcio sintetizadas pelo metodo de via direta

    Energy Technology Data Exchange (ETDEWEB)

    Lima, M.G.; Santos, P.T.A.; Costa, A.C.F.M, E-mail: patyquimica@hotmail.com [Universidade Federal de Campina Grande (DEMA/UFCG), PB (Brazil). Unidade Academica de Engenharia de Materiais

    2012-07-01

    The use of phosphates in bioceramics have attracted the interest of many researchers, especially when it is in the Ca / P = 1.67, which allows the obtention of the hydroxyapatite. This work aims to investigate different calcination temperatures on the structural and morphological characteristics of samples of calcium phosphates synthesized by the method of direct way, aiming for hydroxyapatite as a major phase. For this purpose, we used the calcium hydroxide and phosphoric acid in the Ca / P = 1.67. The samples were calcined at temperatures of 600, 700, 800, 900, 1000, 1100, 1200 and 1350°C/2h, and characterized by XRD, FTIR and Size Distribution. The XRD showed that 600-800°C, the major phase is the tricalcium phosphate, 900-1100°C, there is a phase calcium pyrophosphate. And at 1200 and 1350 ° C, there is a phase monetite. The infrared spectrum showed the characteristic vibrations of calcium phosphates in all conditions studied. It was observed from the results of FTIR presence of bands of the P-OH group and HPO{sub 4}{sup 2-}, PO{sub 4}{sup 3}, for all temperatures studied. The highest average size of agglomerates of 108.05 mM was observed for the temperature of 1100 ° C. (author)

  6. Physical-mechanical characterization of hydroxyapatite-titanium oxide composites made by the polymeric sponge method; Caracterizacao fisico-mecanica de compositos porosos de hidroxiapatita-titania confeccionados pelo metodo da esponja polimerica

    Energy Technology Data Exchange (ETDEWEB)

    Galdino, A.G.S.; Zavaglia, C.A.C. [Universidade Estadual de Campinas (FEM/UNICAMP), SP (Brazil)

    2011-07-01

    Bioceramics have been used as bone reconstruction materials since last decades, where hydroxyapatite is one of the most used for this purpose. However, hydroxyapatite's mechanical strength is not so high when compared to other bioceramics. This work aimed on characterizing physically and mechanically composites of HA-TiO{sub 2}. Samples were made by the polymeric sponge method with 70% - 30% wt., 60% - 40% wt. and 50% - 50% wt. of HA - TiO{sub 2}, calcined at 550 deg C for sponge burning and sintered at 1250 deg C, 1300 deg C and 1350 deg C. Samples were submitted to mechanical essays of compression and Hardness Vickers and to physical essays of water absorption, apparent density, burning linear retraction and apparent density. Results showed relatively better than those of pure hydroxyapatite and they are in accordance with the literature. (author)

  7. Production of the antimicrobial peptide UBI 29-41 labelled with 99mTc by an indirect method; Obtencion del peptido antimicrobiano UBI 29-41 marcado con 99mTc empleando un metodo indirecto

    Energy Technology Data Exchange (ETDEWEB)

    Nevares, Noemi; Crudo, Jose L; Zapata, Miguel; Castiglia, Silvia G. de [Comision Nacional de Energia Atomica, Ezeiza (Argentina). Dept. de Radioquimica

    2003-07-01

    The infection processes are a major problem in human health causing a high number of human deaths all around the world. Diagnostic imaging in nuclear medicine is an attractive option in the detection of infection processes due to its sensitivity. The antimicrobial peptides are very important in the development of new radiopharmaceuticals, since their antimicrobial activity towards a great variety of microorganisms have been proven. The aim of this work was to obtain the antimicrobial peptide UBI 29-41 labelled with technetium 99 m, by an indirect method via NHS-Hynic and tricine as a coligand, and evaluate its stability and its ability to discriminate between infection and inflammation sites. The radiochemical purity of the labeling procedure was 95.5{+-}1,2 %. The cysteine challenge showed a great stability of the 99mTc UBI-Hynic, and the stability in human serum showed that the 81% of the radioactivity remained bounded to UBI-Hynic at 48 hs of incubation. The bio distribution's studies showed main elimination via kidney of 99mTc UBI-Hynic and the target/non target ratio was 1,81 for infected mice and 1,16 for inflamed mice. (author)

  8. Analisis comparativo de una metaheuristica en base a algoritmo genetico vs un metodo de ramificacion y corte para un caso de entrega y recolección con restricciones de ventana de horario

    Directory of Open Access Journals (Sweden)

    Lopez, F.

    2004-07-01

    Full Text Available En la solución de problemas combinatorios, es importante evaluar el costo-beneficio entre la obtención de soluciones de alta calidad en detrimento de los recursos computacionales requeridos. El problema planteado es para el ruteo de un vehículo con entrega y recolección de producto y con restricciones de ventana de horario. En la práctica, dicho problema requiere ser atendido con instancias de gran escala (nodos ≥100. Existe un fuerte porcentaje de ventanas de horario activas (≥90% y con factores de amplitud ≥75%. El problema es NP-hard y por tal motivo la aplicación de un método de solución exacta para resolverlo en la práctica, está limitado por el tiempo requerido para la actividad de ruteo. Se propone un algoritmo genético especializado, el cual ofrece soluciones de buena calidad (% de optimalidad aceptables y en tiempos de ejecución computacional que hacen útil su aplicación en la práctica de la logística. Para comprobar la eficacia de la propuesta algorítmica se desarrolla un diseño experimental el cual hará uso de las soluciones óptimas obtenidas mediante un algoritmo de ramificación y corte sin límite de tiempo. Los resultados son favorables.

  9. Contact stress by the method of finite elements of the steel AISI 1045 hardened by roller; Tensiones de contacto por el metodo de elementos finitos del acero AISI 1045 endurecido por rodillo

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez-columbie, T.; Rodriguez-Gonzalez, I.; Alcantara-Borges, D.; Fernandez-Guilarte, E.

    2012-11-01

    In this paper, the tense-deformational behavior is analyzed by means of simulation using the finite element method for AISI 1045 cold rolled deformed steel. ANYSYS V.10 software was used in this study. Revolution number, compressive strength and tool feed rate were the variables considered in the deformation process. They allowed determining the contact stress of the deformed material. The material used was 30 mm diameter and 100 mm length. Samples of 30 mm diameter and 3 mm thickness were prepared for the optical microscopic observation, which were compared to the results obtained from the simulation. The tensile status of the deformed samples was evaluated as from the reduction of the average size of the grains as per the strength applied. This study intends to show that the cold hardening method is a surface hardening option. (Author)

  10. Response matrix of regular moderator volumes with {sup 3}He detector using Monte Carlo methods; Matriz respuesta de volumenes regulares de moderador con detector de {sup 3}He mediante metodos Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Baltazar R, A.; Vega C, H. R.; Ortiz R, J. M.; Solis S, L. O.; Castaneda M, R. [Universidad Autonoma de Zacatecas, Unidad Academica de Ingenieria Electrica, Programa de Doctorado en Ingenieria y Tecnologia Aplicada, Av. Lopez Velarde s/n, 98000 Zacatecas, Zac. (Mexico); Soto B, T. G.; Medina C, D., E-mail: raigosa.antonio@hotmail.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Programa de Doctorado en Ciencias Basicas (Ciencias Nucleares), Cipres No. 10, Fracc. La Penuela, 98060 Zacatecas, Zac. (Mexico)

    2017-10-15

    In the last three decades the uses of Monte Carlo methods, for the estimation of physical phenomena associated with the interaction of radiation with matter, have increased considerably. The reason is due to the increase in computing capabilities and the reduction of computer prices. Monte Carlo methods allow modeling and simulating real systems before their construction, saving time and costs. The interaction mechanisms between neutrons and matter are diverse and range from elastic dispersion to nuclear fission; to facilitate the neutrons detection, is necessary to moderate them until reaching electronic equilibrium with the medium at standard conditions of pressure and temperature, in this state the total cross section of the {sup 3}He is large. The objective of the present work was to estimate the response matrix of a proportional detector of {sup 3}He using regular volumes of moderator through Monte Carlo methods. Neutron monoenergetic sources with energies of 10{sup -9} to 20 MeV and polyethylene moderators of different sizes were used. The calculations were made with the MCNP5 code; the number of stories for each detector-moderator combination was large enough to obtain errors less than 1.5%. We found that for small moderators the highest response is obtained for lower energy neutrons, when increasing the moderator dimension we observe that the response decreases for neutrons of lower energy and increases for higher energy neutrons. The total sum of the responses of each moderator allows obtaining a response close to a constant function. (Author)

  11. Study of the precision and trueness of the Brazilian method for ethanol and gasoline determination; Estudo da precisao e exatidao do metodo brasileiro para determinacao de etanol e gasolina

    Energy Technology Data Exchange (ETDEWEB)

    Zucchini, Ricardo R.; Hinata, Patricia [Instituto de Pesquisas Tecnologicas (IPT), Sao Paulo, SP (Brazil); Gioseffi, Carla S.; Franco, Joao B.S. [Instituto Brasileiro de Petroleo, Gas e Biocombustiveis (IBP), Rio de Janeiro, RJ (Brazil); Nascimento, Cristina R.; Torres, Eduardo S. [Agencia Nacional do Petroleo, Gas Natural e Biocombustiveis (ANP), Rio de Janeiro, RJ (Brazil)

    2008-07-01

    The determination of repeatability and reproducibility standard deviations of an analytical method, s{sub r} and s{sub R}, obtained by Interlaboratory program, makes it possible to calculate many kinds of precision limits of the method, which are needed in every laboratory's routine result comparisons and also in between-laboratories comparisons. This paper presents the results of the first interlaboratory trial, accomplished in the Brazilian petroleum sector, performed to define the trueness and precision of the Brazilian standard method for the determination of fuel anhydrous ethylic alcohol content in gasoline, that was performed by 34 experienced laboratories. The r and R values were 0,7 and 2,3 and main factors that would improve and optimize the method are presented. (author)

  12. Determination of rare earth and uranium in reference biological materials certified by the method of neutron activation analysis; Determinacao de terras raras e de uranio em materiais biologicos de referencia certificados pelo metodo de analise por ativacao com neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Lais H.P.; Saiki, Mitiko, E-mail: laispaciulli@gmail.com, E-mail: mitiko@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    The objective of this study was to evaluate the precision and accuracy of the determinations of Sc, La, Ce, Nd, Sm, Eu, Tb, Yb, Lu and U in certified reference materials (CRMs). To solve the problem of interference from fission products of U in the determination of lanthanides were obtained correction factors for this interference for {sup 140}La, {sup 141}Ce, {sup 143}Ce, {sup 153}Sm and {sup 147}Nd. The experimental procedure of Neutron Activation Analysis consisted of irradiating aliquots of each of the CRMs with synthetic standards of elements under thermal neutron flux of the IEA-R1 nuclear reactor, followed by gamma-ray spectrometry using a high-resolution hyperpurity GE detector. The analyzes of CRMs indicate good accuracy and precision of results, demonstrating the feasibility of applying of established procedure in NAA of elements studied in organic vegetable matrices.

  13. Use of radioanalytical methods for determination of uranium, neptunium, plutonium, americium and curium isotopes in radioactive wastes; Utilizacao de metodos radioanaliticos para a determinacao de isotopos de uranio, plutonio, americio e curio em rejeitos radioativos

    Energy Technology Data Exchange (ETDEWEB)

    Geraldo, Bianca

    2012-07-01

    Activated charcoal is a common type of radioactive waste that contains high concentrations of fission and activation products. The management of this waste includes its characterization aiming the determination and quantification of the specific radionuclides including those known as Difficult-to-Measure Radionuclides (RDM). The analysis of the RDM's generally involves complex radiochemical analysis for purification and separation of the radionuclides, which are expensive and time-consuming. The objective of this work was to define a methodology for sequential analysis of the isotopes of uranium, neptunium, plutonium, americium and curium present in a type of radioactive waste, evaluating chemical yield, analysis of time spent, amount of secondary waste generated and cost. Three methodologies were compared and validated that employ ion exchange (TI + EC), extraction chromatography (EC) and extraction with polymers (ECP). The waste chosen was the activated charcoal from the purification system of primary circuit water cooling the reactor IEA-R1. The charcoal samples were dissolved by acid digestion followed by purification and separation of isotopes with ion exchange resins, extraction and chromatographic extraction polymers. Isotopes were analyzed on an alpha spectrometer, equipped with surface barrier detectors. The chemical yields were satisfactory for the methods TI + EC and EC. ECP method was comparable with those methods only for uranium. Statistical analysis as well the analysis of time spent, amount of secondary waste generated and cost revealed that EC method is the most effective for identifying and quantifying U, Np, Pu, Am and Cm present in charcoal. (author)

  14. Modification of the hydrotalcite with sodium stearate and its influence in the polyurethane nanocomposites obtained by the in situ polymerization; Nanocompositos de poliuretano/hidrotalcita via polimerizacao in situ: efeito da modificacao da argila e dos metodos dispersivos

    Energy Technology Data Exchange (ETDEWEB)

    Carmo, Danieli M. do, E-mail: danielimcarmo@hotmail.com [Universidade Federal Rural do Rio de Janeiro (UFRRJ), Seropedica, RJ (Brazil); Oliveira, Marcia G. de [Instituto Nacional de Tecnologia (INT), Rio de Janeiro, RJ (Brazil); Soares, Bluma G. [Universidade Federal do Rio de Janeiro (IMA/UFRJ), Rio de Janeiro, RJ (Brazil). Instituto de Macromoleculas Profa. Eloisa Mano

    2015-07-01

    Nanocomposites of PU with synthetic hydrotalcite and organoclay were obtained by the in situ polymerization. The addition of clay in the reaction has occurred with and without dispersion previous, using equipment ultraturrax and ultrasound bath. The results of XRD and FTIR confirmed the clay organophilization process. The viscosity analysis of the dispersions showed increased nanocarga-monomer interaction with the time counter, especially for samples containing LDH-st. Such interactions with possibility reaction between the phases may have contributed to the unbalance of the stoichiometry required for polymerization, resulting in lower molecular weight polymer formed in situ. As a result there was minor degradation temperature values, modulus and viscosity for samples subjected to the methodologies TBT and T. However, these methods in conjunction with LDH-st were fundamentals to improving dispersion in the matrix, accord to visual analysis. (author)

  15. Research into methods of dust prevention in mechanised winning in thin coal seams. Investigacion de metodos de prevencion del polvo, en el arranque mecanizado de capas estrechas de carbon

    Energy Technology Data Exchange (ETDEWEB)

    Martinez Fidalgo, M.; Alvarez Santullano, L.; Eguidazu Pujades, J.L.; Gonzalez del Valle, S.; Cordera Fernandez, J.V.; De Arriba de la Iglesia, J. (Instituto Nacional de Silicosis (Spain))

    1989-09-01

    Concerns the research work carried out jointly by HUNOSA and the National Institute of Silicosis regarding dust prevention on mechanised faces in thin coal seams using shearers with a drum diameter of less than 600 mm. This work was supported by the Directorate General for mines and Ocicarbon. 10 figs., 1 tab.

  16. Reshaping of computational system for dosimetry in neutron and photons radiotherapy based in stochastic methods - SISCODES; Remodelagem do sistema computacional para dosimetria em radioterapia por neutrons e fotons baseado em metodos estocasticos - SISCODES

    Energy Technology Data Exchange (ETDEWEB)

    Trindade, Bruno Machado

    2011-02-15

    This work shows the remodeling of the Computer System for Dosimetry of Neutrons and Photons in Radiotherapy Based on Stochastic Methods . SISCODES. The initial description and status, the alterations and expansions (proposed and concluded), and the latest system development status are shown. The SISCODES is a system that allows the execution of a 3D computational planning in radiation therapy, based on MCNP5 nuclear particle transport code. The SISCODES provides tools to build a patient's voxels model, to define a treatment planning, to simulate this planning, and to view the results of the simulation. The SISCODES implements a database of tissues, sources and nuclear data and an interface to access then. The graphical SISCODES modules were rewritten or were implemented using C++ language and GTKmm library. Studies about dose deviations were performed simulating a homogeneous water phantom as analogue of the human body in radiotherapy planning and a heterogeneous voxel phantom, pointing out possible dose miscalculations. The Soft-RT and PROPLAN computer codes that do interface with SISCODES are described. A set of voxels models created on the SISCODES are presented with its respective sizes and resolutions. To demonstrate the use of SISCODES, examples of radiation therapy and dosimetry simulations for prostate and heart are shown. Three protocols were simulated on the heart voxel model: Sm-153 filled balloon and P-32 stent, to prevent angioplasty restenosis; and Tl-201 myocardial perfusion, to imaging. Teletherapy with 6MV and 15MV beams were simulated to the prostate, and brachytherapy with I-125 seeds. The results of these simulations are shown on isodose curves and on dose-volume histograms. The SISCODES shows to be a useful tool for research of new radiation therapy treatments and, in future, can also be useful in medical practice. At the end, future improvements are proposed. I hope this work can contribute to develop more effective radiation therapy treatments. (author)

  17. H{sub 2} as source of renewable energy: production through catalytic methods by means of the reforming of methanol; H{sub 2} como fuente de energia renovable: produccion por metodos cataliticos mediante el reformado de metanol

    Energy Technology Data Exchange (ETDEWEB)

    Perez H, R; Lopez, P; Gutierrez M, A; Gutierrez W, C; Mondragon G, G; Mendoza A, D [ININ, Departamento de Tecnologia de Materiales, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Angeles Ch, C [Instituto Mexicano del Petroleo, Programa de Ingenieria Molecular, Eje Central Lazaro Cardenas Norte 152, Col. San Bartolo Atepehuacan, 07730 Mexico D. F. (Mexico); Arenas A, J., E-mail: raul.perez@inin.gob.m [UNAM, Instituto de Fisica, Ciudad Universitaria, 04510 Mexico D. F. (Mexico)

    2010-07-01

    The fuel cells transform the chemical energy stored in the connection H-H of the H{sub 2} molecule in electric energy and water vapor when is combines with the oxygen. Even when the hydrogen has a high potential as energy source, its handling is difficult (storage and transport). This has motivated the search of hydrogen production methods in situ starting from liquid fuels like the methanol or ethanol through the reaction of reforming. The methanol is a fuel of easy availability for fuel cells with electronic applications and of transport. Although the methanol energy density is approximately half of the gasoline and diesel, it is more reagent and can be used directly in fuel cells or can also be reformed to low temperatures for the hydrogen obtaining to be used in fuel cells of proton exchange. In this article the results obtained of the systems, Cu-Ni/ZrO{sub 2} and Ag-Au(1-D)-CeO{sub 2} are presented and can be competitive to generate H{sub 2} and being used in the fuel cells to generate energy. (Author)

  18. Preparation and LSC Standardization of ''89Sr (DNP) Using the CIEMAT/NIST Method; Preparacion del ''89Sr(DNP) y calibracion por centelleo liquido, mediante el metodo CIEMAT/NIST

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Barquero, L.; Los Arcos Merino, J. M.; Grau Malonda, A.

    1994-07-01

    A procedure for preparation of liquid scintillation counting samples of the strontium DNP complex, labelled with ''89Sr, is described, the chemical quench, the counting stability and spectral evolution of this compound is studied in six scintillators, Toluene, Toluene-alcohol, Dioxane-naphthalene, HiSafe II, Ultima- Gold and Instagel. The liquid scintillation standardization of 89Sr-DNP by the CIEMAT/NIST method, using HiSafe II and Ultima-Gold scintillators, has been carried out. The discrepancies between experimental and computed efficiencies are lower than 0.38% and 0.48%, respectively. The solution has been standardized in terms of activity concentration to an overall uncertainty of 0,38%. (Author) 10 refs.

  19. Liquid Scintillation Counting Standardization of {sup 2}2NaCl by te CIEMAT/NIST method; Calibracion por Centelleo Liquido del ''22NaCl, mediante el metodo CIEMAT/NIST

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Barquero, L.; Grau Carles, A.; Grau Malonda, A.

    1995-07-01

    We describe a procedure for preparing a stable solution of ''22NaCl for liquid scintillation counting and its counting stability and spectral evolution in Insta-Gel''R is studied. The solution has been standardised in terms of activity concentration by the CIEMAT/NIST method with discrepancies between experimental and computed efficiencies lower than 0.4 % and an overall uncertainty of 0.35 %. (Author) 4 refs.

  20. Liquid scintillation counting standardization of 125I in organic and inorganic samples by the CIEMAT/NIST method; Calibracion por centelleo liquido del 125I en muestras inorganicas y organicas, mediante el metodo CIEMAT/NIST

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Barquero, L.; Grau Malonda, A.; Los Arcos Merino, J. M.; Grau Carles, A.

    1994-07-01

    The liquid scintillation counting standardization of organic and inorganic samples of ''I25I by the CIEMAT/NIST method using five different scintillators is described. The discrepancies between experimental and computed efficiencies are lower than 1.4% and 1.7%, for inorganic and organic samples, respectively, in the interval 421-226 of quenching parameter. Both organic and inorganic solutions have been standardized in terms of activity concentration to an overall uncertainty of 0.76%. (Author) 14 refs.

  1. Ana?lisis cinemático de la marcha en pacientes con pie zambo tratados mediante el me?todo de Ponseti frente a la te?cnica quiru?rgica de liberacio?n posterior

    OpenAIRE

    Ferrando, A.; Salom Taverner, M.; Page, A.

    2018-01-01

    El objetivo principal de este proyecto consiste en valorar la evolución de la marcha en niños en edad preadolescente tratados mediante el método de Ponseti frente a los tratados mediante liberación posterior a partir de técnicas de valoración de la marcha mediante análisis biomecánico. Material y Métodos Estudio retrospectivo de casos y controles aprobado por el comité de ética. Grupo 1: 28 niños (39 pies) tratados mediante liberación posterior. Grupo 2: 18 pacientes (31 pies) tratados median...

  2. Evaluation method for material flow and MSW calorific power object of differentiated collection; Metodo per la valutazione dei flussi di materia e del potere calorifico di RSU oggetto di raccolta differenziata

    Energy Technology Data Exchange (ETDEWEB)

    Florio, G. [Rende, Cosenza, Univ. della Calabria (Italy). Dip. di Meccanica; Giordano, R.; Greco, G.

    1998-11-01

    The method developed in the present paper, starting from a knowledge of demographic data, the growth of refuse production and the material composition of solid urban refuse, allows the evaluation of the effects of the aims of differentiated collection, over a period of time, provided for by the norm in force (D.Lgs 22/97). This evaluation is effected both on the quantity of individual materials to be recovered and on the average MSW calorific power to be incinerated. The model was applied to the Region of Calabria and a parametric study was carried out on the average calorific power of the refuse produced by the two different strategies employed to attain the aims provided for by the Ronchi Act (mainly dry and mainly wet differentiated collection). [Italiano] La metodologia sviluppata nel presente lavoro, interamente automatizzata in ambiente Excel, permette, a partire dalla conoscenza di dati demografici, di crescita della produzione di rifiuti e della composizione merceologica del rifiuto solido urbano, di valutare, in un fissato periodo temporale, gli effetti degli obiettivi di raccolta differenziata previsti dalla norma vigente (D.Legs. 22/97) sia sui quantitativi dei singoli materiali da recuperare sia sul potere calorifico medio del RSU da incenerire. Oltre ad una applicazione alla Regione Calabria e` presentato, a titolo esemplificativo, uno studio parametrico sul potere calorifico medio del rifiuto per effetto di due diverse strategie di raggiungimento degli obiettivi previsti dal decreto Ronchi (raccolta differenziata a prevalenza secco e a prevalenza umido).

  3. Synthesis and characterization of Ni-CeO{sub 2} catalysts by the hydrothermal method; Sintesis y caracterizacion de catalizadores de Ni-CeO{sub 2} por el metodo hidrotermal

    Energy Technology Data Exchange (ETDEWEB)

    Lazcano O, I.

    2013-07-01

    At the present time the necessity exists to reduce the level of atmospheric pollutants, because these are the main originators of such problems as: the greenhouse effect, acid rain, global heating, among others and that are affecting the human being seriously. In this context, is necessary to look for new solutions that contribute to the improvement of the problems without appealing to limitations in the energy production, because this would imply a non only delay in the economic development, but also in the cultural, technological and of research in our country. An alternative for the energy solution is the use of renewable fuels, because they will decrease the production costs with the time, as well as to diminish the dependence of the fossil fuels, contributing this way to the improvement of the environment quality. The use of the hydrogen as an alternating fuel to the petroleum, is intends as energy solution. The objective of the present work is to develop Ni-CeO{sub 2} catalysts through the hydrothermal method for the hydrogen production starting from the partial oxidation reaction of methanol for the clean fuel generation that does not produce polluting emissions to the environment. As well as, to determine the importance of the metallic load in the catalytic activity for which catalysts to 1 and 2% in weight of Ni were prepared. To achieve these objective different techniques were used to characterize the prepared catalysts, as: Temperature Programmed Reduction to evidence the metal-support interaction, Scanning Electron Microscopy (Sem) to determine the morphology of the catalysts, Surface Area (Bet) with respect to the adsorption-desorption of N{sub 2} and X-Rays Diffraction (XRD) to know the crystalline structure of the catalysts. Also the catalytic properties (activity and selectivity) were studied under the reaction: CH{sub 3}OH + 1/2 O{sub 2} obtaining as products to the CO{sub 2} + 2H{sub 2}, with the help of the multi-tasks equipment Rig-100 that operated to temperatures among 200 at 450 C. In the results was observed that the Ni-CeO{sub 2} catalyst to 2% in nickel weight was more efficient in the interval of 275 to 400 C regarding the catalyst to 1% of Ni and the CeO{sub 2} matrix. (Author)

  4. Congenital anomalies of the inferior vena cava: importance of multiplanar imaging methods: an iconographic essay; Anomalias congenitas da veia cava inferior: valor dos metodos multiplanares em seu diagnostico - ensaio iconografico

    Energy Technology Data Exchange (ETDEWEB)

    Viana, Sergio Lopes; Mendonca, Jose Luiz Furtado de; Freitas, Flavia Mendes Oliveira [Clinica Radiologica Vila Rica, Brasilia, DF (Brazil)] (and others). E-mail: radiolog@uol.com.br

    2006-10-15

    The inferior vena cava is the result of a complex embryologic process which takes place between 6 and 8 weeks of intra-uterine life. Several variations can occur during this process, and a defective embryogenesis of this vessel may lead to the development of anatomic variants. Although many of these variants are asymptomatic, the radiologist should be aware of them and of the potential medico-legal issues involved, especially in cases in which abdominal surgery or hemodynamic procedures are contemplated. In this paper, the major congenital anomalies involving the inferior vena cava are reviewed under the form of a pictorial essay, highlighting the role of the multiplanar imaging methods (volumetric computed tomography and magnetic resonance imaging) in their diagnosis. Keywords: Congenital variations; Inferior vena cava; Renal veins; Computed tomography; Magnetic resonance imaging. author)

  5. Solution of the transport equation in stationary state, in one and two dimensions, for BWR assemblies using nodal methods; Solucion de la ecuacion de transporte en estado estacionario, en 1 y 2 dimensiones, para ensambles tipo BWR usando metodos nodales

    Energy Technology Data Exchange (ETDEWEB)

    Xolocostli M, J V

    2002-07-01

    The main objective of this work is to solve the neutron transport equation in one and two dimensions (slab geometry and X Y geometry, respectively), with no time dependence, for BWR assemblies using nodal methods. In slab geometry, the nodal methods here used are the polynomial continuous (CMPk) and discontinuous (DMPk) families but only the Linear Continuous (also known as Diamond Difference), the Quadratic Continuous (QC), the Cubic Continuous (CC), the Step Discontinuous (also known as Backward Euler), the Linear Discontinuous (LD) and the Quadratic Discontinuous (QD) were considered. In all these schemes the unknown function, the angular neutron flux, is approximated as a sum of basis functions in terms of Legendre polynomials, associated to the values of the neutron flux in the edges (left, right, or both) and the Legendre moments in the cell, depending on the nodal scheme used. All these schemes were implemented in a computer program developed in previous thesis works and known with the name TNX. This program was modified for the purposes of this work. The program discreetizes the domain of concern in one dimension and determines numerically the angular neutron flux for each point of the discretization when the number of energy groups and regions are known starting from an initial approximation for the angular neutron flux being consistent with the boundary condition imposed for a given problem. Although only problems with two-energy groups were studied the computer program does not have limitations regarding the number of energy groups and the number of regions. The two problems analyzed with the program TNX have practically the same characteristics (fuel and water), with the difference that one of them has a control rod. In the part corresponding to two-dimensional problems, the implemented nodal methods were those designated as hybrids that consider not only the edge and cell Legendre moments, but also the values of the neutron flux in the corner points. In this geometry nodal, continuous and discontinuous schemes were used. For the continuos schemes, only the Bi Quadratic (BiQ) and the Bi Cubic (BiC) were considered. In the case of the discontinuous ones two nodal schemes were considered, namely the Discontinuous Bi Linear (DBiL) and Discontinuous Bi Quadratic (DBiQ). The nodal schemes applied use from 4 up to 16 interpolation parameters per cell. These schemes are-defined for a set D{sub c} of interpolation parameters and a polynomial space S{sub h} corresponding to each one of the nodal schemes considered. All these four nodal hybrid schemes were implemented in a computer program called TNHXY starting from the computer program TNXY developed in previous thesis works. Several subroutines wae added to calculate the average neutron flux for each cell and for each energy group, generating two versions, one for the continuous schemes and one for the discontinuous schemes. For this geometry, two benchmark problems of the ANL-7416 document were analyzed. They are 7x7 BWR fuel assemblies, one without control rod and the other one with control rod. The computer program was also applied to a MOX assembly proposed by the Nuclear Energy Agency and it is considered as a reference problem. The results obtained for the one-dimensional problems using TNX for the effective multiplication factor were compared with the ones obtained with the code ANISN/PC. TNX code shows a faster convergence within four significant figures for the case with no control rod and three significant figures for the case with control rod (using double precision). These results suggest TNX is a very useful tool for this kind of calculations. For X Y geometry, the results obtained with TNHXY were compared with those calculated with the code TWOTRAN. To get these results, several spatial (1x1, 2x2, 4x4 per cell) and angular meshes (S{sub 2}, S{sub 4}, S{sub 6}, and S{sub 8}) were used. The results for the problem with no control rod were practically the same as those obtained with TWOTRAN using the scheme DBiL that is the simplest one. The results for the other three schemes are practically the same, except for differences in the fourth or fifth significant figure. For the MOX assembly, the results obtained for k{sub eff} with TNHXY were compared with the values obtained with the codes HELIOS, MCNP4B/ENDF-VI and CPM-3. The results obtained with TNHXY are comparable with those reported with the other codes. Particularly, when k{sub eff} values obtained with TNHXY are compared with those obtained with MCNP-4B/ENDF-VI the error was less than 0.5%. Finally, the cross sections used in TNHXY were obtained with the code HELIOS. (Author)

  6. Obtain ceramic porous alumina-zirconia by replica method calcium phosphate coated; Oobtencao de ceramicas porosas de alumina-zirconia pelo metodo da replica recobertas com fosfato de calcio

    Energy Technology Data Exchange (ETDEWEB)

    Silva, A.D.R.; Rigoli, W.R.; Osiro, Denise; Pallone, E.M.J.A., E-mail: adinizrs@yahoo.com.br [Universidade de Sao Paulo (FZEA/USP), Pirassununga, SP (Brazil). Faculdade de Zootecnia e Engenharia de Alimentos; Lobo, A.O. [Universidade do Vale do Paraiba (UNIVAP), Sao Jose dos Campos, SP (Brazil)

    2016-07-01

    Biomaterials used in bone replacement, including porous bioceramics, are often used as support structure for bone formation and repair. The porous bioceramics are used because present features as biocompatibility, high porosity and pore morphology that confer adequate mechanical strength and induce bone growth. In this work were obtained porous specimens of alumina containing 5% by inclusion of volume of zirconia produced by the replica method. The porous specimens had its surface chemically treated with phosphoric acid and were coated with calcium phosphate. The coating was performed using the biomimetic method during 14 days and an initial pH of 6.1. The porous specimens were characterized using the follow techniques: porosity, axial compression tests, microtomography, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and pH measurements SBF solution. The results showed specimens with suitable pore morphology for application as biomaterial, and even a reduced time of incubation favored the calcium phosphate phases formation on the material surfaces. (author)

  7. Clinic implementation of method Zacarias for the correction of errors of convergence of optimization of IMRT in lung; Implementacion clinica del metodo Zacarias para la correccion de errores de convergencia de optimizacion en la IMRT en pulmon

    Energy Technology Data Exchange (ETDEWEB)

    Pardo Perez, E.; Molina Lopez, M. Y.; Ruiz Maqueda, S.; Castro Novais, J.; Counago Lorenzo, F.

    2013-07-01

    The implemented procedure is acceptable per a unit of radiophysic since it does not increase planning time in more than 30 - 45 minutes. Plans thus obtained show an improvement in dosimetric parameters for a small increase in the complexity of the plan, without appreciable increase risk organ doses. (Author)

  8. Numerical Calculation of Transport Based on the Drift-Kinetic Equation for Plasmas in General Toroidal Magnetic Geometry: Numerical Methods; Calculo Numerico de Transporte mediante la Ecuacion Cinetica de Deriva para Plasmas en Geometria Magnetica Toroidal: Metodos Numericos

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, J. M.; Lopez-Bruna, D.

    2009-10-12

    In this report we continue with the description of a newly developed numerical method to solve the drift kinetic equation for ions and electrons in toroidal plasmas. Several numerical aspects, already outlined in a previous report [Informes Tecnicos Ciemat 1165, mayo 2009], will be treated now in more detail. Aside from discussing the method in the context of other existing codes, various aspects will be now explained from the viewpoint of numerical methods: the way to solve convection equations, the adopted boundary conditions, the real-space meshing procedures along with a new software developed to build them, and some additional questions related with the parallelization and the numerical integration. (Author) 16 refs.

  9. Visualisation of Proficiency Test Exercise by Means of Kiri Plots. Informatics Application; Metodo de Visualizacion de los Resultados de las Pruebas de Capacitacion por medio de la Grafica de Kiri. Aplicacion Informatica

    Energy Technology Data Exchange (ETDEWEB)

    Gasco, C.; Trinidad, J. A.

    2012-09-13

    This report describes the visualisation procedure of the proficiency tests by means of Kiri Plots, based on three tests: z-score, zeta-score and the relative uncertainty outlier. The results assessment of the intercomparison exercises and proficiency tests among Spanish environmental radioactivity laboratories and Spanish Nuclear Power Plants Laboratories is performed by Environmental Radioactivity and Radiological Surveillance Unit following the ISO-43 e ISO/ IUPAC standards and applying the z-score test. The application of new graphics methods and tests to a better evaluation of uncertainties reported by Labs is described in this paper. An informatics programme has been developed in Visual Basic for applications that allows the graphic representation of Tables and Figures automatically in an excel-sheet and later statistical simulations changing the ratios between the reference value uncertainties and the concentration activities values from the participants laboratories. (Author) 26 refs.

  10. Development of a new technic for breast attenuation correction in myocardial perfusion scintigraphy using computational methods; Desenvolvimento de uma nova tecnica para correcao da atenuacao por tecidos moles em cintilografia de perfusao miocardica utilizando metodos computacionais

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Anderson de

    2015-07-01

    Introduction: One of the limitations of nuclear medicine studies are false-positive results that lead to unnecessary exams and procedures associated to morbidity and costs to the individual and society. One of the most frequent causes for reducing the specificity of myocardial perfusion imaging (MPI) is photon attenuation, especially by breast in women. Objective: To develop a new technique to compensate the photon attenuation by women breasts in myocardial perfusion imaging with {sup 99m}Tc-sestamibi, using computational methods. Materials and methods: A procedure was proposed which integrates Monte Carlo simulation, computational methods and experimental techniques. Initially, were obtained the chest attenuation correction percentages using a phantom Jaszczak and breast attenuation percentages by Monte Carlo simulation method, using the EGS4 program. The percentages of attenuation correction were linked to individual patients' characteristics by an artificial neural network and a multivariate analysis. A preliminary technical validation was done by comparing the results of the MPI and catheterism (CAT), before and after applying the technique to 4 patients. The t test for parametric data, Wilcoxon, Mann-Whitney and X{sup 2} for the others were used. Probability values less than 0.05 were considered statistically significant. Results: Each increment of 1 cm in the thickness of breast was associated to an average increment of 6% on photon attenuation, while the maximum increase related to breast composition was about 2%. The average chest attenuation percentage per unit was 2.9%. Both, the artificial neural network and linear regression, showed an error less than 3% as predictive models for percentage of female attenuation. The anatomical-functional correlation between MPI and CAT was maintained after the use of the technique. Conclusion: Results suggest that the proposed technique is promising and could be a possible alternative to other conventional methods employed today. (author)

  11. A new method for verification of IMRT treatments on patient geometry files using DYNALOG; Un metodo para la verficacion de tratamientos de IMRT sobre la geometria del paciente utilizando los archivos Dynalog

    Energy Technology Data Exchange (ETDEWEB)

    Infante Utrilla, M. A.; Calama Santiago, J. A.; Lavado Rodriguez, M. E.

    2011-07-01

    The aim of this work is to implement a novel method of verification of IMRT treatments, using this information to reconstruct the flow in the scheduler and calculate the dose, comparing dose distributions in 2D and 3D histograms obtained with the initials. This procedure lacks the limitations and uncertainties of the dosimetric detectors used in the verification of model (ionization chamber, film, etc..) Or ILD, also allowing to quantify the differences on the patient.

  12. Using the direct method in organophilization of clay chocolate 'A' with organic surfactant; Utilizacao do metodo direto na organofilizacao da argila chocolate 'A' com surfactante organico

    Energy Technology Data Exchange (ETDEWEB)

    Patricio, A.C.L.; Sousa, A.B.; Silva, M.M. da; Rodrigues, M.G.F.; Laborde, H.M., E-mail: cadigena@hotmail.com [Universidade Federal de Campina Grande (UFCG), PB (Brazil). Centro de Ciencias e Tecnologia. Unidade Academica de Engenharia Quimica

    2012-07-01

    During the development of this work, we studied the preparation of organoclays through direct method, starting from the natural clay Chocolate 'A' using the quaternary ammonium salt, chloride, alkyl dimethyl benzyl ammonium (Dodigen). The samples were characterized by X-Ray Diffraction (XRD), Infrared Spectroscopy in the Region (IV), Gravimetric and Differential Thermal Analysis (DTA / TGA) and swelling of Foster using solvents, gasoline, kerosene and diesel. Was observed by the results XRD, IR and DTA / TG effective intercalation of quaternary ammonium salts of the inter lamellar spaces of the clay, and by Foster swelling test samples treated with the quaternary ammonium salt Dodigen showed affinity for all the solvents tested. (author)

  13. Comparative analysis between P1 and B1 equations for neutron moderation; Analise comparativa entre os metodos de obtencao e das solucoes das equacoes P1 e B1 para moderacao de neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, Aquilino Senra; Silva, Fernando Carvalho da; Cardoso, Carlos Eduardo Santos [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Programa de Engenharia Nuclear

    2000-07-01

    In order to calculate the neutron flux in nuclear reactors, B1 or P1 equations are solved by numerical methods for several groups of energy. The neutron fluxes obtained from the solutions of the B1 and P1 equations are similar when they are applied to large nuclear power reactors. However, an important difference between the two fluxes is that the system of P1 equations uses one more approximation than the B1 system and then, its flux is less precise. The present work shows the relations between both equations and analyzes for what conditions the two equations systems are equivalent. Furthermore, this equations are numerically solved in 54 groups of energy for a quadrangular arrange. (author)

  14. Irradiation alternative method of manganese sulfate solution by a Pu-Be source for efficiency measurements; Metodo alternativo de irradiacao da solucao de sulfato de manganes por uma fonte de Pu-Be para medicoes de eficiencia

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Fellipe Souza da; Martins, Marcelo Marques; Pereira, Walsan Wagner, E-mail: fellipess@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2015-07-01

    This study intends to create an alternative irradiation system from a Plutonium-Beryllium source for manganese sulphate solution using the Monte Carlo code. Thus seeking to eliminate the issue of institutes that do not have reactors or particle accelerators in its infrastructure, in order to optimize and provide independence for them to carry out efficiency measurements of MnSO{sub 4} solution in their own locality. The Monte Carlo simulations defined the technical features of this new system so that the solution reaches the maximum neutron capture by manganese in solution. (author)

  15. Plaque of atherosclerosis in aorta: review on atherogenesis, formation of plaque, clinical significance, methods of imaging and treatment; Placa de aterosclerose em aorta: revisao sobre aterogenese, formacao de placa, significado clinco, metodos de imagens e tratamento

    Energy Technology Data Exchange (ETDEWEB)

    Furtado, Rogerio Gomes; Nunes, Colandy G. de Oliveira; Rassi, Junior, Luis; Melato, Luciano Henrique; Turco, Fabio de Paula; Borges, Moises Marcos, E-mail: rogerinhofurtado@gmail.com [Centro de Diagnostico por Imagem (CDI), Goiania, GO (Brazil); Sara, Leonardo [Instituto do Coracao (InCor/FM/USP), Sao Paulo, SP (Brazil)

    2009-04-15

    There is a certain consensus in the literature that the earliest stage of atherogenesis is characterized by the accumulation of spongy cells in the region of the intimal artery. Risk factors such as arterial hypertension, smoking, diabetes mellitus, hypercholesterolemia, male gender and advanced age predispose a person to the formation of plaques in the coronaries and aorta. A greater number of acute coronary events as well as strokes have been observed in people with these risk factors. Strokes are the third cause of death in the USA, with about 40% of the cases being of cryptogenic origin. Since 1989 the atheroma plaques which develop in the thoracic aorta have been considered to be responsible for cerebral and peripheral strokes which were previously considered cryptogenic because imaging techniques such as electrocardiogram transesophageal, computerized tomogram, nuclear magnetic angio-resonance have visualized and characterized the lesions with plaques of arteriosclerosis in the thoracic aorta. The authors of this article made a systematic review in the PUBMED about arteriosclerosis in the aorta and its diagnostic methods. This review includes the physiopathology of the formation of atheroma to the aorta and its consequences, diagnostic methods such as echo transesophageal, computerized tomogram and angio resonance, as well as the advantages and disadvantages of each method of identification of the lesions. An analysis of the clinical significance of the size, form and location of the atheroma plaques in the thoracic aorta were made based on clinical studies, as well as their treatment with anticoagulants, antiplatelet and drugs to reduce cholesterol. (author)

  16. Study radiolabeling of urea-based PSMA inhibitor with 68-Galliu: Comparative evaluation of automated and not automated methods; Estudo de radiomarcacao com Galio-68 do inibidor de PSMA baseado em ureia: avaliacao comparativa de metodo automatizado e nao automatizado

    Energy Technology Data Exchange (ETDEWEB)

    Alcarde, Lais Fernanda

    2016-07-01

    The methods for clinical diagnosis of prostate cancer include rectal examination and the dosage of the prostatic specific antigen (PSA). However, the PSA level is elevated in about 20 to 30% of cases related to benign pathologies, resulting in false positives and leading patients to unnecessary biopsies. The prostate specific membrane antigen (PSMA), in contrast, is over expressed in prostate cancer and founded at low levels in healthy organs. As a result, it stimulated the development of small molecule inhibitors of PSMA, which carry imaging agents to the tumor and are not affected by their microvasculature. Recent studies suggest that the HBED-CC chelator intrinsically contributes to the binding of the PSMA inhibitor peptide based on urea (Glu-urea-Lys) to the pharmacophore group. This work describes the optimization of radiolabeling conditions of PSMA-HBED-CC with {sup 68}Ga, using automated system (synthesis module) and no automated method, seeking to establish an appropriate condition to prepare this new radiopharmaceutical, with emphasis on the labeling yield and radiochemical purity of the product. It also aimed to evaluate the stability of the radiolabeled peptide in transport conditions and study the biological distribution of the radiopharmaceutical in healthy mice. The study of radiolabeling parameters enabled to define a non-automated method which resulted in high radiochemical purity (> 95 %) without the need for purification of the labeled peptide. The automated method has been adapted, using a module of synthesis and software already available at IPEN, and also resulted in high synthetic yield (≥ 90%) specially when compared with those described in the literature, with the associated benefit of greater control of the production process in compliance with Good Manufacturing Practices. The study of radiolabeling parameters afforded the PSMA-HBED-CC-{sup 68}Ga with higher specific activity than observed in published clinical studies (≥ 140,0 GBq/μmol), with a sufficiently long stability, which will enable transport to clinics for use in diagnostic imaging. Biodistribution and pharmacokinetic profiles of the radiolabeled peptide were consistent with those founded in the literature. We concluded that PSMA-HBED-CC-{sup 68}Ga, important diagnostic tool for prostate cancer imaging with PET, can be produced by either automated or not automated method with high radiochemical purity, high synthetic yield and stability of the radiopharmaceutical. (author)

  17. Solution of the transport equation in stationary state, in one and two dimensions, for BWR assemblies using nodal methods; Solucion de la ecuacion de transporte en estado estacionario, en 1 y 2 dimensiones, para ensambles tipo BWR usando metodos nodales

    Energy Technology Data Exchange (ETDEWEB)

    Xolocostli M, J.V

    2002-07-01

    The main objective of this work is to solve the neutron transport equation in one and two dimensions (slab geometry and X Y geometry, respectively), with no time dependence, for BWR assemblies using nodal methods. In slab geometry, the nodal methods here used are the polynomial continuous (CMPk) and discontinuous (DMPk) families but only the Linear Continuous (also known as Diamond Difference), the Quadratic Continuous (QC), the Cubic Continuous (CC), the Step Discontinuous (also known as Backward Euler), the Linear Discontinuous (LD) and the Quadratic Discontinuous (QD) were considered. In all these schemes the unknown function, the angular neutron flux, is approximated as a sum of basis functions in terms of Legendre polynomials, associated to the values of the neutron flux in the edges (left, right, or both) and the Legendre moments in the cell, depending on the nodal scheme used. All these schemes were implemented in a computer program developed in previous thesis works and known with the name TNX. This program was modified for the purposes of this work. The program discreetizes the domain of concern in one dimension and determines numerically the angular neutron flux for each point of the discretization when the number of energy groups and regions are known starting from an initial approximation for the angular neutron flux being consistent with the boundary condition imposed for a given problem. Although only problems with two-energy groups were studied the computer program does not have limitations regarding the number of energy groups and the number of regions. The two problems analyzed with the program TNX have practically the same characteristics (fuel and water), with the difference that one of them has a control rod. In the part corresponding to two-dimensional problems, the implemented nodal methods were those designated as hybrids that consider not only the edge and cell Legendre moments, but also the values of the neutron flux in the corner points. In this geometry nodal, continuous and discontinuous schemes were used. For the continuos schemes, only the Bi Quadratic (BiQ) and the Bi Cubic (BiC) were considered. In the case of the discontinuous ones two nodal schemes were considered, namely the Discontinuous Bi Linear (DBiL) and Discontinuous Bi Quadratic (DBiQ). The nodal schemes applied use from 4 up to 16 interpolation parameters per cell. These schemes are-defined for a set D{sub c} of interpolation parameters and a polynomial space S{sub h} corresponding to each one of the nodal schemes considered. All these four nodal hybrid schemes were implemented in a computer program called TNHXY starting from the computer program TNXY developed in previous thesis works. Several subroutines wae added to calculate the average neutron flux for each cell and for each energy group, generating two versions, one for the continuous schemes and one for the discontinuous schemes. For this geometry, two benchmark problems of the ANL-7416 document were analyzed. They are 7x7 BWR fuel assemblies, one without control rod and the other one with control rod. The computer program was also applied to a MOX assembly proposed by the Nuclear Energy Agency and it is considered as a reference problem. The results obtained for the one-dimensional problems using TNX for the effective multiplication factor were compared with the ones obtained with the code ANISN/PC. TNX code shows a faster convergence within four significant figures for the case with no control rod and three significant figures for the case with control rod (using double precision). These results suggest TNX is a very useful tool for this kind of calculations. For X Y geometry, the results obtained with TNHXY were compared with those calculated with the code TWOTRAN. To get these results, several spatial (1x1, 2x2, 4x4 per cell) and angular meshes (S{sub 2}, S{sub 4}, S{sub 6}, and S{sub 8}) were used. The results for the problem with no control rod were practically the same as those obtained with TWOTRAN using the scheme DBiL that is the simplest one. The results for th

  18. Solvent-extraction methods applied to the chemical analysis of uranium. III. Study of the extraction with inert solvents; Metodos de extraccion con disolventes aplicados al analisis quimico del uranio. III. Estudio de la extraccion con disolvente inertes

    Energy Technology Data Exchange (ETDEWEB)

    Vera Palomino, J; Palomares Delgado, F; Petrement Eguiluz, J C

    1964-07-01

    The extraction of uranium on the trace level is studied by using tributylphosphate as active agent under conditions aiming the attainment of quantitative extraction by means of a single step process using a number of salting-out agents and keeping inside the general lines as reported in two precedent papers. Two inert solvents were investigated, benzene and cyclohexane, which allowed to derive the corresponding empirical equations describing the extraction process and the results obtained were compared with those previously reported for solvents which, like ethyl acetate and methylisobuthylketone, favour to a more or less extend the extraction of uranium. (Author) 4 refs.

  19. An multi objective heuristic method for calculating the performance of distribution network with distributed generators; Um metodo heuristico multi-objetivo para calcular o desempenho de redes de distribuicao com geradores distribuidos

    Energy Technology Data Exchange (ETDEWEB)

    Ciric, Rade M.; Padilha, Antonio [UNESP, Ilha Solteira, SP (Brazil)

    2002-07-01

    This paper describes the allocation and the performance of the distributed generators installed in a electric power distribution network, and presents a investigation to determining the impacts of distributed generators integration in power systems and the distribution network global performance.

  20. Development of methods for the purification of {sup 67}Ga and {sup 68}Ga for biomolecules labeling; Desenvolvimento de metodos de purificacao do {sup 67}Ga e {sup 68}Ga para a marcacao de biomoleculas

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Renata Ferreira

    2012-07-01

    For more than fifty years, the long-lived {sup 68}Ge/{sup 68}Ga generators have been in development, obtaining {sup 68}Ga without the need of having in house cyclotron, which is a considerable convenience for PET centers that have no nearby cyclotrons. {sup 68}Ga decays 89% by positron emission and low photon emission (1077 keV) and the physical half life of 67.7 minutes is compatible with the pharmacokinetics of low biomolecular weight substances like peptides and antibody fragments. Moreover, its established metallic chemistry allows it to be stably bound to the carrier peptide sequence via a suitable bifunctional chelator, such as DOTA. All these reasons together with the technology of PET/CT allowed advances in molecular imaging, in particular in the diagnosis of neuroendocrine diseases. However, the eluate from the commercial {sup 68}Ge/{sup 68}Ga generators still contains high levels of long lived {sup 68}Ge, besides other metallic impurities, which competes with {sup 68}Ga with a consequent reduction of the labeling yield of biomolecules, such as Fe{sup 3+} and Zn{sup 2+}. Thus, the lower the amount of impurities in the eluate, the competition between the radiolabeled and unlabeled peptide by the receptor will be smaller and the quality of imaging will be better, a subsequent purification step is needed after the generator elution. The aim of this work is to evaluate different purifications methods of {sup 68}Ga to label biomolecules, with emphasis on the study of the chemical impurities contained in the eluate and to develop a new purification method. Several purification methods were studied. Many cationic resin were tested simulating the commercial process. {sup 68}Ga is adsorbed in cationic resin, which is not commercial available and eluted in acid/acetone solution. The use of minor particles of cationic resin AG50W-X4 (200-400 mesh) showed the best results. An innovate method was the extraction chromatography, which is based on the absorption of diisopropyl ether in XAD 16 and {sup 68}Ga recovery in deionized water. Although the results regarding to {sup 68}Ga recovery and the radiochemical separation between {sup 68}Ga and {sup 65}Zn were excellent, there was no reproducibility on the purification of metals. The most promising and innovative method was the {sup 68}Ga purification performed by cationic resin in basic media, which presented the best results, especially regarding the Zn reduction (98 {+-} 2)%, the chemical contaminant found in great abundance in {sup 68}Ga eluate. The total impurities reduction was (95 {+-} 4)%. The peptides DOTATOC/DOTATATE were labeled {sup 68}Ga in three different forms: purified {sup 68}Ga in basic solution, through solvent extraction and no purified {sup 68}Ga. The best result was achieved with DOTATATE labeling with purified {sup 68}Ga in basic media, proving the purification process efficiency. (author)

  1. Zinc oxide films impurified with Ti and prepared by the Sol-gel method; Peliculas de oxido de zinc impurificadas con Ti y preparadas por el metodo Sol-gel

    Energy Technology Data Exchange (ETDEWEB)

    Tirado G, S. [ESFM-IPN, 07738 Mexico D.F. (Mexico); Cazares R, J.M.; Maldonado, A. [CINVESTAV-IPN, A.P. 14-740, 07000 Mexico D.F. (Mexico)

    2006-07-01

    Titanium-doped zinc oxide thin films have been prepared on silicon substrate using the Sol-Gel technique. The structural, morphology, electrical and optical properties of such thin films were studied as a function of titanium concentration (0.5, 1 and 1.5 %) and the thin films thickness. Zinc acetate dihydrate and titanium (VI)-oxy acetylacetonate were used as precursor materials, using 2-methoxyethanol and monoethanolamine as via. The X-ray diffraction spectra show polycrystalline films in all the cases. It can see for all the thin films a preferential growth along the (002) planes where the titanium concentration and also the thin films thickness play an important rule. No structural changes are observed at all. The surface morphology studied shows as the grain size decreases when thin thickness is increases. For titanium concentration of 0.5, 1 and 1.5 % values the grains size increase also. The thin films thickness for titanium concentration of 1.5 % was 500 nm (4v), 400 nm (3v), 180 nm (2v) and 130 nm (1v), values obtained from cross-section micrographs. Highly resistive samples are obtained for substrate soda-lime even showing high transmittance. Better physical properties are required for gas sensors or semitransparent electrodes and other possible applications. (Author)

  2. Determination of silicon and chromium content in gray cast iron by the Van der Pauw method; Determinacion del contenido de silicio y cromo en fundiciones grises mediante el metodo de Van der Pauw

    Energy Technology Data Exchange (ETDEWEB)

    Tremps, E.; Enrique, J. L.; Moron, C.; Garcia, A.; Gomez, A.

    2013-07-01

    In this paper we show a system based on the resistivity measurement of samples of gray cast iron by the Van der Pauw method to calculate the silicon content in the samples. Twenty five trials have been carried out, studying resistive and metallographic characteristics of the samples. This has demonstrated that it is possible to obtain, by this method, the silicon content in molten flat with low content of alloying elements, also the content of chromium in series smelters where the rate of silicon remains constant. (Author)

  3. Positive Prevention: Successful Approaches To Preventing Youthful Drug and Alcohol Use [and] La Prevencion Positiva: Metodos que han tenido exito en la prevencion del uso de drogas y alcohol entre la juventud.

    Science.gov (United States)

    American Association of School Administrators, Arlington, VA.

    The United States has the highest rate of youthful drug abuse of any industrialized country in the world. There is a growing awareness that drug and alcohol use are closely connected to other problems such as teenage suicide, adolescent pregnancy, traffic fatalities, juvenile delinquency, poor school performance, runaways, and dropouts. Youthful…

  4. Comparative study of patient doses calculated with two methods for breast digital tomosynthesis; Estudio de los valores de dosis a pacientes en examenes de tomosintesis de mama estimados con dos metodos distintos

    Energy Technology Data Exchange (ETDEWEB)

    Castillo, M.; Chevalier, M.; Calzado, A.; Garayo, J.; Valverde, J.

    2015-07-01

    In this study, the average glandular doses (DG) delivered in breast tomosynthesis examinations were estimated over a sample of 150 patients using two different methods. In method 1, the conversion factors air-kerma to DG used were those tabulated by Dance et al. and in method 2 were the ones from Feng et al. The protocol for the examination followed in the unit of this study consists in two views per breast, each view composed by a 2D acquisition and a tomosynthesis scan (3D). The resulting DG values from both methods present statistically significant differences (p=0.02) for the 2D modality and were similar for the 3D scan (p=0.22). The estimated median value of DG for the most frequent breasts (thicknesses between 50 and 60 mm) delivered in a single 3D acquisition is 1.7 mGy (36% and 17% higher than the value for the 2D mode estimated with each method) which lies far below the tolerances established by the Spanish Protocol Quality Control in Radiodiagnostic (2011). The total DG for a tomosynthesis examination (6.0 mGy) is a factor 2.4 higher than the dose delivered in a 2D examination with two views (method 1). (Author)

  5. Implementation of the e-learning method for technological research institutes utilization; Implantacao de metodos de ensino a distancia para uso em institutos de pesquisas tecnologicas utilizando como meio a internet

    Energy Technology Data Exchange (ETDEWEB)

    Pinheiro, Valderes Fernandes; Silva, Aucyone Augusto da; Rogero, Jose Roberto [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)]. E-mail: valma@ecodigit.com.br

    2002-07-01

    The e-learning is a subject that is attracting all teaching institution at the present because the number of interested student is growing in the same proportion of communication technology facilities is getting more easy and low cost to be used. Most of universities and colleges are adapting their classes to on-line and a new market is growing very fast all around the world. Of course that these institutions are also worried about the quality of the online teaching materials and also methodologies used to delivery them. This paper will explore some models that are being used in online classes and also will present the contribution of this research in developing a new teaching model that will applied in the technological research institutions like IPEN/CNEN-SP. This model should be technical and economical self-sufficient and it is emphasized in the customers technological needs. The model's variables are interactivity levels with the technology, use of internet tools (chat, forum, discussion list), teacher and student relationship, knowledge evaluation, etc. (author)

  6. Implementation of a method for patient-specific IMRT treatment verification using dynalog files; Aplicacion de un metodo para la verificacion de tratamientos de imrt sobre la anatomia del paciente utilizando archivos dynalog

    Energy Technology Data Exchange (ETDEWEB)

    Calama Santiago, J. A.; Infante Utrilla, M. A.; Lavado Rodriguez, M. E.

    2011-07-01

    The aim of this work is to implement a simple method of intensity modulated radiation therapy (IMRT) verification on the patient anatomy using dynalog files. Monitor units (MU) fraction and leaf positions, both planned and actually positioned during treatment, are sampled every 55 ms and stored in these files. This information was used in the treatment planning system to reconstruct the given fluence and to recalculate the absorbed dose in the patients CT, comparing absorbed dose distributions and histograms with those initially planned. Differences mainly appeared in areas with high absorbed dose gradients at the beginning and at the end of the radiation fields. These differences were lower than 3% in absorbed dose for most cases. No significant differences were found on dose-volume histograms. With proper linac and multileaf collimator commissioning, and a more stringent linac, treatment planning and record and verify system quality assurance program, this procedure allows patient-specific IMRT treatment verification, unlike conventional methods. (Author) 15 refs.

  7. Observability in electric power networks: a method of ways of factorization in state estimation with equality restrictions; Observabilidade em redes de energia: um metodo de caminhos de fatoracao em estimacao de estado com restricoes de igualdade

    Energy Technology Data Exchange (ETDEWEB)

    Vicentino, Flavio Antonio

    1997-07-01

    A theory of network observability that mixes graph concepts and factorization of the gain matrix G has been recently developed. It uses data already available in Power System Operating Centers. That theory is easy to understand and implement and does not require subroutines other than the ones used in static state estimation. However, this new theory has been implemented only for the case of state estimation in Normal Equation Formulation (N E). However, the N E Method presents some inherent numerical difficulties. Such numerical difficulties are usually related to the disparity in the measurements weights (high values for zero-injections measurements and low values for pseudo-measurements) and the presence of short lines in the network, as well. In order to solve such numerical difficulties, new methods have come up, such as: Normal Equation Method with Equality Constraints (N E/C), where Lagrange's Multiplier Method can be applied to minimize a function while satisfying a set of constraints; Hachtel's Method, which is formulated the same way as N E/C Method, although an equation of residual vector is introduced in solution process; Hybrid Method, which is a general formulation behaving as the N E/C Method at one extreme, and as Hachtel's Method at the other. Thus, the aim of this work is to treat the adaptation of the network observability Method by using path graphs, with the state estimation in the form of a minimization problem with equality constraints. As the Hybrid Method is a generalization form of the state estimator with constraints, this formulation is used to develop the proposed theory. Extreme case (as the pure Hachtel's Method) are also considered. (author)

  8. Use of the 3DVH Software as a complementary method of IMRT pretreatment evaluation; Utilizacao do Software 3DVH como metodo complementar de avaliacao de pre-tratamento de IMRT

    Energy Technology Data Exchange (ETDEWEB)

    Lyra, Jesse G.P.; Bruning, Fabio F.; Funchal, Melissa; Toledo, Hugo V.; Bornatto, Pricila; Fernandes, Tatiane C.O., E-mail: jesse_lyra@hotmail.com [Hospital Erasto Gaertner / Liga Paranaense de Combate ao Cancer (LPCC), Departamento de Radioterapia, Curitiba, PR (Brazil)

    2013-04-15

    The aim of this study is to compare the method of treatment planning evaluation for IMRT using the gamma index to the method of the 3DVH Software. The 3DVH Software was used with the MapCheck2 detector 2D array under a 6MV x-ray beam of linear accelerator equipped with 120 leafs MLC. Nine treatment plans of prostate patients chose randomly and fully anonimatize were performed in the Eclipse planning system, using the AAA calculation algorithm in IMRT sliding window technique. These plans were approved and treated according to the gamma analysis criteria of the institution. The comparisons were made in absolute dose and normalized at maximum dose for each field and then with the 3DVH Software the Dmax, Dmean, D15%, D25%, D35% and D50% parameters for the bladder and rectum, Dmean for the bulb, Dmax for the femur and D95% for the PTV were evaluated. In the planar analysis by field, the plans studied had a minimum of 97.5% approval. The PTV-related differences have relative variation from 1.3 to 2.2%, that is, greater coverage than expected for this structure. For the organs at risk, the relative differences observed were between -5.3 to 25.8%, which could result in a non-approved plan if these variations are close to the clinical tolerances of the OAR. The results show that even a plan compatible with greater than or equal to 95% of the points, the gamma analysis does not give enough information if this plan can or cannot be approved for treatment and that there is a need for more detailed verification of the plan which considers not only the planar evaluation, but also the evaluation of the DVH measured, and the 3DVH Software proved be adequate for this analysis. (author)

  9. Optimization of the synthesis of a high specific activity 125{sup I}-labelled hapten for radioimmunoassays; Optimizacion de un metodo de preparacion de un radiohapteno-125''I para ria de alta actividad especifica

    Energy Technology Data Exchange (ETDEWEB)

    Suraez, C.; Paz, D.; Simon, M. A.; Romero del Hombrebueno, B.

    1994-07-01

    In this first report it is described the synthesis, separation and purification of the 2-radioiodinated histamine- I-labelled histamine by a mixed anhydride reaction. About 75% incorporation of I{sup -}125, from Na{sup 1}25I, was achieved with a molecular ratio of 1:1 mixed anhydride:histamine. The radiochemical purity of the conjugate by TLC was > 99% and its theoretical specific activity, 3850 {mu}Ci/{mu}g. Dissolved in ethanol and held at -20 degree centigree under darkness decomposition on storage didn't exceed 1% per month. (Author) 13 refs.

  10. Meritev izkoristka in nastavitev krmilnih parametrov kaplanove turbine z dolgim cevnim sistemom s primerjalno metodo: Measurement of relative turbine efficiency and adjustment of governing parameters on long penstock Kaplan turbine with comparative method:

    OpenAIRE

    Trebše, Andrej J.

    2004-01-01

    The paper deals with efficiency measurement of Kaplan turbine with relative method (index test) and adjustment of operating of runner and guide vane governing system. At certain longer penstocks the looses in conduit at turbineload operation change the net head. On basis of model test on Kaplan turbine and relative turbine efficiency measurement on prototype the turbine governing system was optimized in accordance with comparative method. Prispevek obravnava meritev izkoristka kaplanove tu...

  11. Application of the generator coordinates method to the intra-molecular proton tunneling in the malonaldehyde molecule; Aplicacao do metodo das coordenadas geradoras ao processo de tunelamento do proton intramolecular na molecula de malonaldeido

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Andre Campos Kersten

    1995-12-31

    The effects of different vibrational modes on the isomerization process of polyatomic molecules, or solvent`s effects on reaction rates are object of up-to-date interest. In general, such many body phenomena are, in principle, multidimensional, and they first require a reduction of relevant degrees of freedom. In order to investigated, some aspects of the intra-molecular proton tunneling on a malonaldehyde molecule, we use the Generator Coordinate Method. The model used to describe such a process is the so-called System-Bath model, where the system is the reaction coordinate and the bath are the intrinsic degrees of freedom (vibrational modes of the molecule), which are described by a harmonic oscillator set linearly coupled to the system. The reduction of the multidimensional problem to the effective unidimensional one is done using a energy related variational principle on the intrinsic degrees of freedom. we obtained analytically a effective Hamiltonian where the effects of the various degrees of freedom reveal themselves in the appearance of a effective mass and in changes of the shape of the potential barrier. The analyticity of the method was crucial on identifying clearly the roles played by the different physical parameters involved. (author) 17 refs., 29 figs.

  12. Sistemas de control de malezas en maiz (Zea mays L.: efecto de metodos de control, densidad y distribucion del cultivo Weed control systems in corn: effects of control methods, density and plant distribution

    Directory of Open Access Journals (Sweden)

    G. Martinez

    1982-12-01

    Full Text Available Con el objetivo de integrar diferentes prácticas culturales en un sistema de control de malezas en maíz, se instaló un ensayo en el Campo Experimental de la Universidad Autónoma Chapingo (México (2250 msnm, precipitación media anual 550 mm, suelo franco, 1.7% M.O. bajo condiciones de secano, en donde se evaluaron dos densidades (44.400 y 66.600 pl/ha, dos distribuciones (normal y equidistante y siete métodos de control de malezas (cyanazine + alachlor (1,2 + 1,92 kg/ha, atrazine + alachlor (1,2 + 1,44 kg/ha, un escarda, dos escardas, testigo siempre desmalezado, testigo siempre desmalezado + dos escardas y testigo siempre enmalezado. Las principales malezas presentes fueron: quelite (Amaranthus sp., perlilla (Lopezia mexicana Jacq., rosilla chita (Galinsoga parviflora Cav., acahual (Encelia mexicana Mart., Sporobulus poiretti (Roem, et Sch. Hichc. y fresadilla (Digitaria sanguinalis (L. Scop.. El aumento de la densidad de siembra no se reflejó en el control de malezas, incidencia de enfermedades, crescimiento vegetativo y reproductivo del cultivo. La distribución equidistante aparejó un mejor control de malezas, en relación a la distribución normal, pero la incidencia de enfermedades fue mayor, lo que quizá pudo haber determinado la ausencia de diferencias en crecimiento vegetativo, un menor número de mazorcas/ha y consecuentemente la ausencia de respuesta en rendimiento de grano. De los tratamientos químicos, atrazine + alachlor tuvo un comportamiento superior a cyanazine + alachlor, en control de malezas, aunque sólo fue detectable estadisticamente en las evaluaciones. No hubo diferencia entre ambos en la incidencia de enfermedades, ni en su efecto sobre el cultivo. aunque el rendimiento de cyanazine + alachlor fue ligeramente inferior. Los métodos químicos fueron superiores a los mecánicos en control de malezas, pero no difirie -ron en la incidencia de enfermedades ni en los parámetros de desarrollo del cultivo. La realización de una escarda adicional no mejora significativamente el control de malezas, no afectando tampoco la incidencia de enfermedades, ni el desarrollo del cultivo, por lo cual resulta innecesaria. Las escardas tienen como principal efecto eliminar la interfe rencia presentada por las malezas y si éstas son eliminadas de otra manera, la realización de aquéllas no apareja beneficios significativos.An experiment was conducted at the Research Station of the University of Chapingo (Mexico (2250 m above sea level, average annual rainfall 550 mm( loamy soil, 1,7% O.M., where different cultural practices were combined in order to design a weed control system for corn. The work was done under rainfed conditions and the variables included were: two population densities (44.400 and 66.600 pl/ha, two plant distributions (normal and equidistant and seven weed control methods (cyanazine + alachlor (1,2 + 1,92 kg/ha, atrazine + alachlor (1,2 + 1,44 kg/ha, one cultivation, two cultivations, a weeded check, a weeded check + two cultivations and a weedy check. The main weed species were: pigweed (Amaranthus sp., Lopezia mexicana Jacq., hairy galinsoga (Galin-soga parviflora Cay., Encelia mexicana Mart., Sporobulus poiretti (Roem. et Sch. Hich., and large crabgrass (Digitaria sanguinalis (L. Scop.. The increase in plant population had no effect on the degree of weed control, incidence of diseases and crop growth. The equidistant distribution improved weed control over the normal one, but it also had a nigher incidence of diseases; this, is turn, may have caused the lack of differences in vegetative growth, a lower amount of cobs per ha and the lack of difference in grain yield between the two distributions. Atrazine + alachlor was better than cyanazine + alachlor in terms of weed control, although the difference was statistically observed only for the visual ratings. There were no differences between both chemical treatments in terms of incidence of diseases or their effect on crop growth, but grain yield for cyanazine + alachlor was slightly lower. The chemical methods were better than the mechanical ones regarding weed control, but no differences were detected in terms of in cidence of diseases or crop growth. One additional weeding does not improved weed control significantly, nor does it affect the incidence of diseases or crop growth, thus appearing to be unnecessary. The main effect of cultivations is weed control, and if this can be done in any other way, cultivating does not bring about additional benefits.

  13. Different seeds to solve the equations of stochastic point kinetics using the Euler-Maruyama method; Diferentes semillas para solucionar las ecuaciones de la cinetica puntual estocastica empleando el metodo de Euler-Maruyama

    Energy Technology Data Exchange (ETDEWEB)

    Suescun D, D.; Oviedo T, M., E-mail: daniel.suescun@usco.edu.co [Universidad Surcolombiana, Av. Pastrana Borrero - Carrera 1, Neiva, Huila (Colombia)

    2017-09-15

    In this paper, a numerical study of stochastic differential equations that describe the kinetics in a nuclear reactor is presented. These equations, known as the stochastic equations of punctual kinetics they model temporal variations in neutron population density and concentrations of deferred neutron precursors. Because these equations are probabilistic in nature (since random oscillations in the neutrons and population of precursors were considered to be approximately normally distributed, and these equations also possess strong coupling and stiffness properties) the proposed method for the numerical simulations is the Euler-Maruyama scheme that provides very good approximations for calculating the neutron population and concentrations of deferred neutron precursors. The method proposed for this work was computationally tested for different seeds, initial conditions, experimental data and forms of reactivity for a group of precursors and then for six groups of deferred neutron precursors at each time step with 5000 Brownian movements per seed. In a paper reported in the literature, the Euler-Maruyama method was proposed, but there are many doubts about the reported values, in addition to not reporting the seed used, so in this work is expected to rectify the reported values. After taking the average of the different seeds used to generate the pseudo-random numbers the results provided by the Euler-Maruyama scheme will be compared in mean and standard deviation with other methods reported in the literature and results of the deterministic model of the equations of the punctual kinetics. This comparison confirms in particular that the Euler-Maruyama scheme is an efficient method to solve the equations of stochastic point kinetics but different from the values found and reported by another author. The Euler-Maruyama method is simple and easy to implement, provides acceptable results for neutron population density and concentration of deferred neutron precursors and is computationally efficient for obtaining solutions that minimize the problem of rigidity of the equations of the punctual stochastic kinetics at each step of time. (Author)

  14. Skyshine method for photons:comparison between theoretical approach and numerical simulation by Monte Carlo method; Skyshine para fotons: comparacao entre abordagem teorica e simulacao numerica pelo metodo de Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Falcao, R.C.; Facure, A.; Santini, E.S. [Comissao Nacional de Energia Nuclear (CNEN), Rio de Janeiro, RJ (Brazil)]. E-mail: ross@cnen.gov.br; afsoares@cnen.gov.br; esantini@cnen.gov.br; Silva, A.X. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Programa de Engenharia Nuclear]. E-mail: ademir@com.ufrj.br

    2005-07-01

    The skyshine method is commonly used to compute the dose around radiotherapy facilities, when the roof shielding is projected considering that there will be no occupancy upstairs. In these cases, there will be no need to have the usual 1,5-2,0 m thick ceiling, and the construction costs can be considerably reduced. The semi-empirical expression commonly used to compute these doses show a poor agreement with the experimental dose measurements found in the literature. In this paper the MCNP code was used to simulate the transport of photons in some radiotherapy rooms, with shielding projects approved by the Brazilian Nuclear Energy Commission (CNEN), and whose roof shielding were designed according to the above-mentioned method. These simulations are then compared with the calculations presented in the shielding projects and a clear discrepancy is observed between both results. (author)

  15. Neutron Skyshine in shielding projects of radiotherapy: comparison between theoretical approach and simulation by Monte Carlo method; 'Skyshine' de neutrons em projetos de blindagens de radioterapia: comparacao entre abordagem teorica e simulacao por metodo de Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Falcao, R.C.; Facure, A. [Comissao Nacional de Energia Nuclear (CNEN), Rio de Janeiro, RJ (Brazil); Santini, E.S. [Comissao Nacional de Energia Nuclear (CNEN), Rio de Janeiro, RJ (Brazil); Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil); Silva, A.X. [Coordenacao dos Programas de Pos-Graduacao de Engenharia (PEN/COPPE/UFRJ), RJ (Brazil). Programa de Engenharia Nuclear

    2005-07-01

    In this work, the MCNP code is used to simulate the transport of neutrons in a room of radiotherapy, whose shieldings are designed according to the method of skyshine (scattering in the atmosphere). The simulations are compared with the results obtained from empirically established expressions, which are normally used for designing the ceilings of the rooms facilities, ensuring that dose rates (neutrons + photons) around them do not exceed the maximum limits allowed by the standards of the CNEN. Good agreement is observed between the doses calculated according to these expressions and those obtained through simulation by Monte Carlo in the case of rooms without ceiling, and an overestimate of the calculations by a factor 2 or 3 in relation to the simulations, in the case of rooms with ceiling.

  16. Analytical Evaluation to Determine Selected PAHs by HPLC in a Type 2 Fuel; Evaluacion Analitica de 4 Metodos de Determinacion de PAHs medianteHPLC en un Fuel de Tipo II

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Alonso, S.; Perez Pastor, R. M.; Sevillano Castano, M. L.; Escolano Segovia, O.; Garcia Frutos, F. J.

    2009-05-21

    An evaluation of analytical parameters to determine selected PAHs in a fuel oil type II by HPLC coupled to fluorescence and diode detectors is presented. The study was focused on four conventional treatments of these kinds of oil samples and the main objective was giving a measure of confidence level of PAH results in the fuel oil. This study was performed in the frame of the project Assessment of natural attenuation of PAHs in agricultural soil contaminated with fuel from an accidental spill (Spanish National Plain I+D+I, CTM2007-64537). This paper is presented as follows: Analysis of reference material 1582 (NIST) by using the four kinds of sample treatments of interest. Application of variance analysis to compare results obtained from type II fuel by using each sample treatment and chromatographic detector. Finally, a statistic calculation was performed to measure uncertainty components in chromatographic analysis. (Author)

  17. Methods of Particle Detection in Free Neutron Decay; Methode de detection des particules dans une desintegration de neutrons libres; Metod obnaruzheniya chastits pri raspade svobodnogo nejtrona; Metodo para la deteccion de particulas en la desintegracion de neutrones libres

    Energy Technology Data Exchange (ETDEWEB)

    Novey, T B [Argonne National Laboratory, Lemont, IL (United States)

    1960-06-15

    A number of experimental studies have recently been completed by the Argonne Group on the decay of polarized neutrons in order to elucidate the structure of the weak nuclear interaction. These studies have taken the form of the measurement of the. angular distributions of electrons and protons with respect to the spin direction of the decaying free neutrons. The basic components of the apparatus which will be discussed are: 1. The one-meter iron-cobalt mirror which selects a beam of highly polarized neutrons and the methods for determination of the polarization. 2. The electron detector comprising a 10 cm diameter, 6 mm thick mosaic of anthracene crystals, and its light pipe system. 3. The proton detector, a 14-stage electron multiplier system, the first stage with a 15x15 cm opening, tapering in four stages to a standard 10-stage multiplier structure, and its entrance baffles for angular resolution. 4. The electronic system which selects pulses from the detectors having the proper time sequence, relative time-delay and pulse-height to allow indentification of a neutron decay. (author) [French] Le groupe Argonne a termine recemment des etudes experimentales sur la desintegration des neutrons polarises, en vue de mettre en lumiere le processus de l'interaction nucleaire faible. Ces etudes consistaient a mesurer les distributions angulaires d'electrons et de protons par rapport a la direction du spin des neutrons libres en voie de desintegration. Les principaux elements de l'appareillage qui sera decrit sont: 1. Le miroir de ferro-cobalt d'un metre, qui isole un faisceau de neutrons hautement polarises, ainsi que les methodes permettant de determiner la polarisation. 2. Le detecteur electronique qui comprend une mosaique de 10 cm de diametre et de 6 mm d'epaisseur en cristaux d'anthracene, et son systeme selectif. 3. Le detecteur de protons, un systeme multiplicateur electronique a 14 etages, le premier ayant une ouverture de 15x15 cm se retrecissant en 4 etages pour aboutir a un multiplicateur ordinaire a 10 etages et ses chicanes d'entree pour resolution angulaire. 4. Le systeme electronique qui isole dans les detecteurs les impulsions venant des detecteurs et ayant les caracteristiques voulues de frequence, de retard relatif et d'amplitude et permet ainsi d'identifier la des- integration d'un neutron. (author) [Spanish] En el Laboratorio de Argonne se ha llevado a cabo recientemente una serie de estudios experimentales sobre la desintegracion de neutrones polarizados, con el fin de elucidar las modalidades de la interaccion nuclear a bajas energias. Estos estudios han consistido en mediciones de la distribucion angular de electrones y protones con respecto al sentido del spin de los neutrones libres que sufren la desintegracion. Los componentes fundamentales del aparato que el autor describe en la memoria son: 1. Un espejo de hierro y cobalto, de un metro, que selecciona un haz de neutrones altamente polarizados y permite determinar el grado de polarizacion aplicando distintos procedimientos . 2. El detector de electrones, consistente en un mosaico de cristales de antraceno de 10 cm de diametro y 6 mm de espesor, y en un dispositivo de canalizacion luminosa. 3. El detector de protones, formado por un sistema multiplicador de electrones de 14 etapas, la primera de las cuales con una abertura de 15x15 cm, que va disminuyendo en cuatro pasos hasta una estructura multiplicadora usual de 10 etapas, y sus deflectores de entrada para lograr la resolucion angular. 4. El sistema electronico que selecciona los impulsos que, al ser adecuados los intervalos con que se suceden, su defasaje en tiempo y su amplitud, hacen posible la identificacion de una desintegracion neutronica. (author) [Russian] Nedavno Argonnskoj gruppoj byl zavershen ryad ehksperimental'nykh issledovanij po raspadu polyarizovannykh nejtronov s tem, chtoby prolit'svet na strukturu slabogo yadernogo vzaimodejstviya. EHti issledovaniya nosili formu izmereniya uglovykh raspredelenij ehlektronov i protonov po otnosheniyu k napravleniyu spina raspadayushchikhs ya svobodnykh nejtronov. Osnovnymi uzlami pribora, kotoryj budet obsuzhdat'sya v doklade, yavlyayutsya: 1. ZHelezo-kobal'tovo e zerkalo razmerom v 1 metr, sobirayushchee puchok vysoko polyarizovanny kh nejtronov, i metody opredeleniya polyarizatsii. 2. EHlektronnyj detektor diametrom v 10 sm s 6 .mm mozaikoj antratsenovykh kristallov i sistemoj osvetitel'nykh trubok. 3. Protonovyj detektor s sistemoj ehlektronnogo mnozhitelya v 14 kaskadov, prichem pervyj kaskad s zazorom 15x15 sm; detektor sobiraetsya v 4 kaskada do standartnogo 10-ti kaskadnogo mnozhitelya; vkhod ego otvodit uglovoe razlozhenie. 4. EHlektronnaya sistema, otbirayushchaya impul'sy u detektorov i imeyushchaya sootvetstvuyushchu yu posledovatel'nost ' vo vremeni, otnositel'nuyu zaderzhku vremeni i impul'snuyu vysotu dlya opredeleniya raspada nejtronov. (author)

  18. Radioactive Metrology Methods in the USSR; Methodes de metrologie de la radioactivite en URSS; Metody metrologii radioaktivnosti v SSSR; Metodos de Metrologia de la Radiactividad Aplicados en la Union de Republicas Socialistas Sovieticas

    Energy Technology Data Exchange (ETDEWEB)

    Aglintsev, K K; Bochkarev, V V; Grablevskij, V N; Karavaev, F M

    1960-06-15

    The authors review the methods practised in the USSR and in particular at the Mendeleev Institute of Metrology at Leningrad, for the reproduction, by means of standardized apparatus, of the units of measurement used for radioactivity (curie, gramme-equivalent of Ra, roentgen and rad). As regards the radionuclides, the standard sources regularly produced in the USSR are of two types: (1) Model sources, which are used in standardizing other radioactive substances by comparison and in calibrating radiometric and monitoring instruments; and (2) Control sources, which are used exclusively for checking the functioning of measuring instruments and the reproducibility of the data yielded by them. Model {beta} sources are made of radionuclides selected so as to provide a range of maximum energies of 0.018-2.3 MeV. Control {beta} sources are prepared from either Sr{sup 90} + Y{sup 90,} Tl{sup 204} or Pm{sup 147}. These sources cover a wide range of activities of between 20 and 10{sup 9} disintegrations per minute. Model {gamma} sources are made of either Ra, Co{sup 60} or Cs{sup 137}. The range of activities covered by these standards falls between the orders of magnitude of 10{sup 11} and 5 gramme-equivalents of Ra. The control {gamma} sources are based on the same radionuclides as mentioned above. Their activities cover a very wide range and they vary very considerably in form and size. Lastly, the model neutron sources are of two types: Ra-a{alpha}-Be (containing 1-1000 mg Ra) and Pu-a{alpha}-Be (containing 0.01-15 g Pu). The Ra-a-Be sources consist of a compressed mixture of RaBr{sub 2} and powdered Be with a Ra/Be ratio of 1 : 6 by weight. The Pu-{alpha}-Be sources consist of an alloy (PuBe{sub 13}) of these two metals. (author) [French] Les auteurs passent en revue les methodes pratiquees en USSR, et plus particulierement a l'Institut de metrologie ''Mendeleev'' de Leningrad, pour la reproduction - a l'aide d'appareils standardises - des unites de mesure utilisees en radioactivite (curie, equivalent-gramm e de Ra, roentgen, rad). En ce qui concerne les radionuclides, les sources etalons couramment produites en URSS sont de deux types: 1. Sources modeles servant a l'etalonnage par comparaison d'autres preparations radioactives, ainsi qu'au calibrage d'appareils radiometrique s et de moniteurs de rayonnement; 2. Sources de controle servant exclusivement a la verification du fonctionnement et au controle de la reproductibilite des indications fournies par les appareils de mesure. Les sources a modeles sont preparees par depot electrolytique sur platine d'emetteurs convenablemen t choisis (U naturel, U{sup 233}, Pu{sup 239}, Am{sup 241}). Peuvent etre fournies des activites variant de 30 a 10{sup 6} desintegrations par minute. Les sources a de controle sont constituees par un depot electrolytique de Pu{sup 239} en couche de masse specifique variant de 3.10{sup -9} a 0.7 mg/cm{sup 2}, ce qui corres- pond a des activites allant de 10 jusqu'a 10{sup 8} desintegrations par minute. Les sources {beta} modeles sont constituees de radionuclides choisis de facon a assurer une gamme d'energies limites allant de 0.018 MeV a 2.3 MeV. Les sources {beta} de controle sont faites soit de Sr{sup 90} + Y{sup 90}, soit de Tl{sup 204}, soit enfin de Pm{sup 147}. Ces sources couvrent une large gamme d'activites, entre 20 et 10{sup 9} desintegrations par minute. Les sources {gamma} modeles sont constituees soit de Ra, soit de Co{sup 60}, soit enfin de Cs{sup 137}. La gamme des activites de ces etalons est comprise entre les ordres de grandeur 10{sup -11} et 5 equivalents-gramm e de Ra. Les sources {gamma} de controle sont preparees a partir des memes radionuclides que ci-dessus. Les activites couvrent une gamme tres etendue, les sources ayant des formes et dimensions tres variees. Enfin, les sources modeles de neutrons sont de deux sortes: Ra-{alpha}-Be (contenant de 1 a 1000 mg de Ra) et Pu-{alpha}-Be (contenant de 0.01 a 15 g Pu). Les sources Ra-{alpha}-Be sont constituees par un melange comprime de RaBr{sub 2} et de Be en poudre avec un rapport en poids Ra/Be = 1 : 6. Les sources Pu-{alpha}-Be sont formees d'un alliage (PuBe{sub 13}) de ces deux metaux. (author) [Spanish] Los autores estudian los procedimientos que se emplean en la Union Sovietica, y especialmente en el Instituto de Metrologia ''Mendeleev'' de Leningrado, para la determinacion - con ayuda de aparatos normalizados - de las unidades de medida utilizadas en la esfera de la radiactividad (curie, equivalente gramo del Ra, roentgen y rad). En la Union Sovietica se producen actualmente dos clases de fuentes patron: 1. Fuentes modelo que sirven para llevar a cabo trabajos de contraste por comparacion de otros preparados radiactivos, asi como para el calibrado de aparatos radiometricos y de monitores de radiaciones; 2. Fuentes de control, destinadas exclusivamente a la verificacion del funcionamiento de los aparatos de medicion y al control de la reproducibilidad de las indicaciones facilitadas por los mismos. Las fuentes a modelo se preparan depositando electroliticament e emisores adecuados (U natural, U{sup 233}, Pu{sup 239}, Am{sup 241}) sobre platino. Pueden suministrarse fuentes cuyas actividades se encuentren comprendidas entre 30 y 10{sup 6} desintegraciones por minuto. En cuanto a las fuentes a de control, se obtienen mediante deposito electrolitico de Pu{sup 239} en una capa cuya masa especifica abarca de 3 X 10{sup -9} a 0.7 mg/cm{sup 2}; estos valores corresponden a actividades de 10 y 10{sup 8} desintegracione s por minuto, respectivamente. Para las fuentes{beta} modelo, se eligen radionuclidos que proporcionan una gama de energias limite de 0.018 a 2.3 MeV. Las fuentes {beta} de control estan constituidas por Sr{sup 90} + Y{sup 90}, TI{sup 204} o Pm{sup 147}. Las actividades de estas fuentes abarcan de 20 a 10{sup 9} desintegracione s por minuto. Las fuentes {gamma} modelo estan formadas por Ra, So{sup 60} o Cs{sup 137}. Los limites inferior y superior de la actividad de estos patrones son 10{sup -11} y 5 equivalentes gramo del Ra, respectivamente . Las fuentes {gamma} de control se preparan partiendo de los mismos radionuclidos que las fuentes y modelo. Sus actividades abarcan un intervalo muy amplio y las fuentes presentan formas y dimensiones sumamente diversas. Por ultimo, se utilizan dos clases de fuentes neutronicas modelo Ra-{alpha}-Be (con un contenido de 1 a 1000 mg de Ra) y Pu-{alpha}-Be (conteniendo de 0.01 a 15 g de Pu). Las fuentes Ra-{alpha}-Be consisten en una mezcla comprimida de RaBr{sub 2} y de Be en polvo, siendo la razon ponderal Ra/Be igual a 1/6. En cuanto a las fuentes Pu-{alpha}-Be, se preparan con una aleacion (PuBe{sub 13}) de estos dos metales. (author) [Russian] Avtory opisyvayut metody, primenyaemye v SSSR, i, v chastnosti, v institute metrologii im. Mendeleeva (Leningrad) dlya vosproizvodstv a pri pomoshchi standartnykh apparatov edinits izmereniya, ispol'zuemykh v radioaktivnosti (kyuri, gramm-ehkvivalen t radiya, rentgen, rad). Dlya radionuklido v v Sovetskom Soyuze proizvodyatsya istochnikiehtalony dvukh vidov: 1. Model'nye istochniki dlya sravnitel'nog o ehtalonirovani ya drugikh radioaktivnykh preparatov, a takzhe dlya kalibrovki radiometricheski kh priborov i kontrol'nykh priborov za izlucheniem; 2. Kontrol'nye istochniki, sluzhashchie isklyuchitel'n o dlya proverki raboty i kontrolya za vosproizvodimost' yu ukazanij izmeritel'ny kh priborov. Model'nye a-istochniki prigotovlyayuts ya pri pomoshchi ehlektrolitiche - skogo osazhdeniya na platine dolzhnym obrazom vybrannykh izluchatelej (estestvennyj uran, uran-233, plutonij-239, ameritsij-241). EHti istochniki mogut obespechivat' aktivnost' ot do 10{sup 6} raspadov v minutu. Kontrol'nye {alpha}-istochniki prigotovlyayuts ya putem ehlektroliticheskog o osazhdeniya plutoniya-239 v vide sloya s plotnost'yu ot 3 X 10-{sup 9} do 0,7 mg/em2, chto sootvetstvuet aktivnosti ot 10 do 10{sup 8} raspadov v minutu. Model'nye {beta}-istochniki prigotovlyayuts ya iz radionuklidov , vybrannykh takim obrazom, chtoby obespechit' diapazon ehnergij ot 0,018 mehv do 2,3 mehv. Kontrol'nye {beta}-istochniki prigotovlyayuts ya libo iz strontsiya-90 plyus ittrij-90, libo iz talliya-204, libo iz prometiya-147. EHti istochniki okhvatyvayut shirokij diapazon aktivnosti ot 20 do 10{sup 9} raspadov v minutu. Model'nye {gamma}-istochniki prigotovlyayuts ya libo iz radiya, libo iz kobal'ta-60, libo iz tseziya-137. diapazon aktivnostej ehtikh ehtalonov okhvatyvaet velichiny ot 10-{sup 11} do 5 grammov-ehkvivalento v radiya. Kontrol'nye u-istochniki prigotovlyayuts ya iz vysheukazanny kh radionuklidov. Aktivnosti okhvatyvayut ochen' shirokij diapazon, poskol'ku istochniki imeyut ves'ma razlichnuyu formu i razmery. Nakonets, model'nye istochniki nejtronov byvayut dvukh vidov: radija-{alpha}-berillij (soderzhashchij ot 1 do 1000 mg radiya) i plutonij-{alpha}-berilli j (soderzhashchij ot 0,01 do 15 grammov plutoniya). Istochniki radij-{alpha}-berilli j prigotovlyayutsya iz pressovannoj smesi RaBr{sub 2} i poroshkovogo berilliya s vesovym sootnosheniem Ra/Be = 1/6. Istochniki plutonij-a-berilli j obrazuyutsya iz splava (PuBe{sub 13}) ehtikh dvukh metallov. (author)

  19. Calibration of the identiFINDER detector for the iodine measurement in thyroid using the Monte Carlo method; Calibracion del detector identiFINDER para la medicion de yodo en tiroides utilizando el metodo Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Ramos M, D.; Yera S, Y.; Lopez B, G. M.; Acosta R, N.; Vergara G, A., E-mail: dayana@cphr.edu.cu [Centro de Proteccion e Higiene de las Radiaciones, Calle 20 No. 4113 e/ 41 y 47, Playa, 10600 La Habana (Cuba)

    2014-08-15

    This work is based on the determination of the detection efficiency of {sup 125}I and {sup 131}I in thyroid of the identiFINDER detector using the Monte Carlo method. The suitability of the calibration method is analyzed, when comparing the results of the direct Monte Carlo method with the corrected, choosing the latter because the differences with the real efficiency stayed below 10%. To simulate the detector their geometric parameters were optimized using a tomographic study, what allowed the uncertainties minimization of the estimates. Finally were obtained the simulations of the detector geometry-point source to find the correction factors to 5 cm, 15 cm and 25 cm, and those corresponding to the detector-simulator arrangement for the method validation and final calculation of the efficiency, demonstrating that in the Monte Carlo method implementation if simulates at a greater distance than the used in the Laboratory measurements an efficiency overestimation can be obtained, while if simulates at a shorter distance this will be underestimated, so should be simulated at the same distance to which will be measured in the reality. Also, is achieved the obtaining of the efficiency curves and minimum detectable activity for the measurement of {sup 131}I and {sup 125}I. In general is achieved the implementation of the Monte Carlo methodology for the identiFINDER calibration with the purpose of estimating the measured activity of iodine in thyroid. This method represents an ideal way to replace the lack of patterns solutions and simulators assuring the capacities of the Internal Contamination Laboratory of the Centro de Proteccion e Higiene de las Radiaciones are always calibrated for the iodine measurement in thyroid. (author)

  20. Development of a method for the estimation of the useful life of the target in one helical; Desarrollo de un metodo para la estimacion de la vida util del target en una unidad de tomoterapia helicoidal

    Energy Technology Data Exchange (ETDEWEB)

    Delgado Aparicio, J. M.; Garcia Repiso, S.; Martin Rincon, C.; Perez Alvarez, M. E.; Verde Velasco, J. M.; Ramos Pacho, J. A.; Saez Beltran, M.; Gomez Gonzalez, N.; Cons Perez, N.; Sena Espinel, E. de

    2013-07-01

    The objective of this study is to evaluate the effect of this degradation and develop a method for the estimation of the duration of the life of the target independently used internally by the technical service. This can serve to plan the date of intervention when it comes to replace this component. (Author)

  1. Cadmium, lead and silver adsorption in hydrous niobium oxide(V) prepared by precipitation in homogeneous solution method; Adsorcao de chumbo, cadmio e prata em oxido de niobio(V) hidratado preparado pelo metodo da precipitacao em solucao homogenea

    Energy Technology Data Exchange (ETDEWEB)

    Tagliaferro, Geronimo V.; Pereira, Paulo Henrique F.; Rodrigues, Liana Alvares; Silva, Maria Lucia Caetano Pinto da, E-mail: fernandes_eng@yahoo.com.b [Universidade de Sao Paulo (USP), Lorena, SP (Brazil). Escola de Engenharia. Dept. de Engenharia Quimica

    2011-07-01

    This paper describes the adsorption of heavy metals ions from aqueous solution by hydrous niobium oxide. Three heavy metals were selected for this study: cadmium, lead and silver. Adsorption isotherms were well fitted by Langmuir model. Maximum adsorption capacity (Q{sub 0}) for Pb{sup 2+}, Ag{sup +} and Cd{sup 2+} was found to be 452.5, 188.68 and 8.85 mg g{sup -1}, respectively. (author)

  2. RBI - Risk Based Inspection: new technologies and methods applied to inspections of FPSO (Floating Production, Storage and Offloading Vessel) hull; IBR - Inspecao Baseada em Risco: novas tecnologias e metodos aplicados as inspecoes de casco de FPSOs

    Energy Technology Data Exchange (ETDEWEB)

    Farias, Bruno de; Figueiredo, Eduardo; Luiz, Marcio [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil); Meurer, Gustavo; Duarte, Romulo; Oliveira, Thais; Krzonkalla, Viviane [ABS Consulting, Rio de Janeiro, RJ (Brazil)

    2008-07-01

    With the aging of the FPSO's, which are fundamental to the operation Offshore, better techniques and technologies must be applied to assess more accurately the actual efficiency and structural conditions of producing unit. With the emergence of new engineering techniques and equipment and methods of structural inspection, is now possible to use these new technologies to better manage risk and reliability of the structure of the FPSO, with that, the inspections and methods are more rational and efficient. The Risk-Based Inspection is the tool for monitoring operation of industrial plants with systemic use of technology in conjunction with risk analysis and reliability. His concept is applicable to various branches of industry. The companies began their implementation of oil by refineries. The group of ABS Consulting with PETROBRAS has been developing and implementing these new technologies in inspections of hulls of FPSO's. Applied successfully in the units of the Campos basin, these methods are used by the group of Risk-Based Inspection to improve the efficiency of all the steps involved with the structural integrity of the unit. (author)

  3. Method of semi-automatic high precision potentiometric titration for characterization of uranium compounds; Metodo de titulacao potenciometrica de alta precisao semi-automatizado para a caracterizacao de compostos de uranio

    Energy Technology Data Exchange (ETDEWEB)

    Cristiano, Barbara Fernandes G.; Dias, Fabio C.; Barros, Pedro D. de; Araujo, Radier Mario S. de; Delgado, Jose Ubiratan; Silva, Jose Wanderley S. da, E-mail: barbara@ird.gov.b, E-mail: fabio@ird.gov.b, E-mail: pedrodio@ird.gov.b, E-mail: radier@ird.gov.b, E-mail: delgado@ird.gov.b, E-mail: wanderley@ird.gov.b [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Lopes, Ricardo T., E-mail: ricardo@lin.ufrj.b [Universidade Federal do Rio de Janeiro (LIN/COPPE/UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-Graduacao de Engenharia. Lab. de Instrumentacao Nuclear

    2011-10-26

    The method of high precision potentiometric titration is widely used in the certification and characterization of uranium compounds. In order to reduce the analysis and diminish the influence if the annalist, a semi-automatic version of the method was developed at the safeguards laboratory of the CNEN-RJ, Brazil. The method was applied with traceability guaranteed by use of primary standard of potassium dichromate. The standard uncertainty combined in the determination of concentration of total uranium was of the order of 0.01%, which is better related to traditionally methods used by the nuclear installations which is of the order of 0.1%

  4. Transmission of Helicobacter pylori via water for human consumption. Determination by means of the molecular method using PCR; Helicobacter pylori, su transmision a traves de las aguas para el consumo humano. Determinacion por metodo molecular con la PCR

    Energy Technology Data Exchange (ETDEWEB)

    Amo, A. J.; Moreno, C.; Apraiz, D.; Catalan, V. [LABAQUA. Alicante (Spain)

    1998-12-31

    Helicobacter pylori is the cause of chronic gastritis, duodenal ulcers and stomach cancer. Its natural reservoirs and transmission mechanisms are still little understood. The gastro-oral route-especially vomiting and regurgitation-is one transmission path, especially in young children and babies. It has been found in some patients saliva and dental plaque, which suggests a possible oral-oral contagion route. The discovery of H. Pylori human excrement points to a faecal-oral route as the main transmission pathway via water for human consumption. It is therefore important to develop detection methods such as isolation by culture and polymerase chain reaction (PCR) to effectively monitor this pathogen in human drinking water. (Author) 30 refs.

  5. Seeking tools for image fusion between computed tomography, structural and functional magnetic resonance methods for applications in neurosurgery; Ferramentas para fusao de imagens dos metodos de tomografia computadorizada, ressonancia magnetica e ressonancia magnetica funcional para aplicacao pre-neurocirurgica

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, Liana Guerra Sanches da, E-mail: liana@einstein.br [Departamento de Diagnostico por Imagem, Hospital Israelita Albert Einstein - HIAE, Sao Paulo (SP) (Brazil); Amaro Junior, Edson [Faculdade de Medicina, Universidade de Sao Paulo - USP, Sao Paulo, SP (Brazil). Deptartamento de Diagnostico por Imagem; Instituto do Cerebro - InCe, Hospital Israelita Albert Einstein - HIAE, Sao Paulo, SP (Brazil)

    2012-04-15

    To evaluate tools for the fusion of images generated by tomography and structural and functional magnetic resonance imaging. Methods: Magnetic resonance and functional magnetic resonance imaging were performed while a volunteer who had previously undergone cranial tomography performed motor and somatosensory tasks in a 3-Tesla scanner. Image data were analyzed with different programs, and the results were compared. Results: We constructed a flow chart of computational processes that allowed measurement of the spatial congruence between the methods. There was no single computational tool that contained the entire set of functions necessary to achieve the goal. Conclusion: The fusion of the images from the three methods proved to be feasible with the use of four free-access software programs (OsiriX, Register, MRIcro and FSL). Our results may serve as a basis for building software that will be useful as a virtual tool prior to neurosurgery. (author)

  6. Numerical solution of the Neutron Transport Equation using discontinuous nodal methods at X-Y geometry; Solucion numerica de la ecuacion de transporte de neutrones usando metodos nodales discontinuos en geometria X-Y

    Energy Technology Data Exchange (ETDEWEB)

    Delfin L, A

    1997-12-31

    The purpose of this work is to solve the neutron transport equation in discrete-ordinates and X-Y geometry by developing and using the strong discontinuous and strong modified discontinuous nodal finite element schemes. The strong discontinuous and modified strong discontinuous nodal finite element schemes go from two to ten interpolation parameters per cell. They are describing giving a set D{sub c} and polynomial space S{sub c} corresponding for each scheme BDMO, RTO, BL, BDM1, HdV, BDFM1, RT1, BQ and BDM2. The solution is obtained solving the neutron transport equation moments for each nodal scheme by developing the basis functions defined by Pascal triangle and the Legendre moments giving in the polynomial space S{sub c} and, finally, looking for the non singularity of the resulting linear system. The linear system is numerically solved using a computer program for each scheme mentioned . It uses the LU method and forward and backward substitution and makes a partition of the domain in cells. The source terms and angular flux are calculated, using the directions and weights associated to the S{sub N} approximation and solving the angular flux moments to find the effective multiplication constant. The programs are written in Fortran language, using the dynamic allocation of memory to increase efficiently the available memory of the computing equipment. (Author).

  7. Effect of synthesis method on the preparation of lanthanum chromite for using as ceramic pigment; Influencia do metodo de sintese na preparacao de cromita de lantanio para utilizacao como pigmento ceramico

    Energy Technology Data Exchange (ETDEWEB)

    Dantas, G.C.B.; Ferreira, K.M.B.; Pimentel, P.M., E-mail: gerbeson_dantas@hotmail.com [Universidade Federal Rural do Semi-Arido (UFERSA), Mossoro, RN (Brazil); Melo, D.M.A.; Gomes, D.K.S.; Costa, A.F. [Universidade Federal do Rio Grande do Norte (UFRN), RN (Brazil)

    2016-07-01

    In this paper, LaCrO3 perovskites were synthesized by two synthesis methods, in order to compare these methods in function of microstructure and optical properties. The synthesis routes employed were a method that use gelatin as organic precursor and microwave assisted auto-combustion. The resulting powders were calcined at 800 ° C and 1000 ° C for obtaining the perovskite phase. Then, they were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM); UV-Visible spectroscopy and colorimetric analysis for color identification. No significant changes were observed in the powders synthesized by two routes. The oxides presented orthorhombic perovskite structure. The powders synthesized by the gelatin method were single phase. Chromite lanthanide presented grayish hue being darker in perovskites calcined at higher temperatures. (author)

  8. Durand, Guadet e Wagner. L'evoluzione del metodo compositivo tra XIX e XX secolo / Durand, Guadet and Wagner. The evolution of the compositive method between 19th and 20th Century

    Directory of Open Access Journals (Sweden)

    Andrés Caballero Lobera

    2017-01-01

    Full Text Available Il XIX secolo fu un’epoca convulsa per quanto riguarda l’evoluzione del pensiero architettonico. In quanto apice del pensiero illuminista del secolo precedente, tale epoca si manifestò nelle forme dell’architettura storica e allo stesso tempo divenne l’immagine della modernità, stabilendo le basi di quel razionalismo, che avrebbe costruito, ai margini della storia, la sua idea di forma. Tre dei maggiori protagonisti di questo sviluppo, sia per quanto riguarda il loro lavoro di architetti, che come insegnanti, furono Jean-Nicolas-Louis Durand, Julien Guadet e Otto Wagner / The 19th century was a time of upheaval in the development of architectonic thinking. As culmination of the enlightened thinking of the previous century it expressed itself through historical form, and as a reflection of modernity, it established the bases for a rationalist-based architecture that would construct its wish for form outside the margins of history. We highlight the teaching work of three professors and architects in the construction of that thinking: Durand, Guadet and Wagner.

  9. Analysis of uncertainties in a individualized method of estimation activity of {sup 1}31I for hyperthyroid patient; Analisis de incertidumbres en un metodo individualizado de estimacion de actividad de {sup 1}31I para el paciente hipertiroideo

    Energy Technology Data Exchange (ETDEWEB)

    Orellana Salas, A.; Melgar Perez, J.; Arrocha Acevedo, J. F.

    2013-07-01

    The determination of the activity to prescribe the hyperthyroid patients presented difficult consideration uncertainties. The uncertainties associated with the experimental design can exceed 20%, so it should be valued to customize activity therapy of {sup 1}31 I. (Author)

  10. Conjugate view gamma camera method for measuring activity in 131{sup I} treatments; Metodo de la imagen conjugada para la cuantificacion de la actividad en tratamientos de 131{sup I}

    Energy Technology Data Exchange (ETDEWEB)

    Barquero Sanz, R.; Placios, A. M.; Perez, D. M.; Tortosa Oliver, R.; Michel, R.

    2012-07-01

    A quantification method is developed to determine 131{sup I} activity and its associated uncertainty using regions of interest from gamma camera images. Inside a neck phantom, a known activity source is introduced to simulate thyroid remainders in thyroid differentiated cancer. The three parameters that define the accuracy of the method are: net count rates in ROI, the air calibration factor of the gamma camera and the attenuation correction factor. In order to obtain net count rates, four methods for background subtraction are tested. The best procedure to follow is based in two energy windows acquisitions, which gives an activity result of 47 {+-} 5 {mu}Ci Bq, in good agreement with the real activity value for the source, 46 {+-} 5 {mu}Ci. (Author) 12 refs.

  11. Influence of coprecipitation and mechanical mixture methods on the characteristics of nickel oxide-alumina composites; Influencia dos metodos de coprecipitacao e mistura mecanica nas caracteristicas de compositos oxido de niquel-alumina

    Energy Technology Data Exchange (ETDEWEB)

    Cordeiro, G.L.; Yoshito, W.K.; Ussui, V.; Lima, N.B. de; Lazar, D.R.R., E-mail: gcordeiro@usp.br [Instituto de Pesquisas Energeticas e Nucleares (CCTM/IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro de Ciencia e Tecnologia de Materiais

    2014-07-01

    Alumina-supported nickel catalysts are currently used in the reforming process due to low cost and high activity for hydrogen production from alcohols. In this work, the effect of preparation methods on nickel oxide-alumina based materials has been investigated. Nickel content was fixed at 15 wt%. Ceramic powders were obtained by coprecipitation in ammonia medium and mechanical mixture. Coprecipitated materials were calcined in air at 750 deg C to obtain the corresponding oxides. Materials obtained by mechanical mixture were prepared by wet milling of nickel oxide and alumina powders, both synthesized by precipitation and calcination in air at 450 and 750 deg C, respectively. Powders were characterized by X-ray diffraction, nitrogen gas sorption by applying the BET method, laser diffraction, scanning electron microscopy, electrophoretic mobility measurements for zeta potential determination and infrared spectroscopy. The results showed that coprecipitation method allowed the production of mixed oxides with high surface area (232,7 ± 3,2 m{sup 2}.g{sup -1}) and normal granulometric distribution while mechanical mixture led to the formation of materials constituted by gamma alumina and nickel oxide phases, with low surface area (136,2 ± 0,5 m{sup 2}.g{sup -1}) and bimodal granulometric distribution. (author)

  12. Comparison between different methods for inspection of wooden poles in service in electricity distribution networks; Comparacao entre diferentes metodos de inspecao de postes de madeira em servico em redes de distribuicao de energia

    Energy Technology Data Exchange (ETDEWEB)

    Cruz, M.A.O.; Pires, M.; Dedavid, B.A.; Vidor, F.L.R.; Oliveira, W.S.; Abruzzi, R.C. [Pontificia Univ. Catolica do Rio Grande do Sul (PUC-RS), Porto Alegre, RS (Brazil). Programa de Pos-Graduacao em Engenharia e Tecnologia de Materiais (PGETEMA)], Email: mpires@pucrs.br

    2010-07-01

    The pole is the main support structure of the electric network and should be inspected regularly to ensure system security. The aim of this study is to compare traditional and instrumental inspection methods of the wooden poles in service in AES Sul power distribution network (Montenegro, RS). The inspections were conducted in about 180 poles in two measurement campaigns (2001 and 2010). The procedure was based on the traditional inspection (visual inspection, percussion and effort lateral) and instrumental method based on Polux equipment that measures the penetration resistance and moisture content of wood. The results were compared in search of assertiveness of the methods used to subsidize the standardization of inspection procedures. (author)

  13. Analysis of heat transfer on extended surfaces of fuel elements in cooling channels by boundary elements method; Analiza prenosa toplote na orebrenjih gorivnih elementov hladilnih kanalov z metodo robnih elementov

    Energy Technology Data Exchange (ETDEWEB)

    Namestnik, B; Skerget, L; Beadar, D [tehniska fakulteta, Maribor (Yugoslavia)

    1989-07-01

    The paper presents numerical method for evaluating heat transfer on two-dimensional ribbed surfaces. Governing elliptic partial differential equation is transformed to boundary integral equation, and solved by the boundary element method. Efficiency of fins is calculated from boundary heat flux balance. Several test cases have shown usefulness of the presented method. (author)

  14. Analysis of the thermoluminescent signal in the hydroxyapatite synthesized by the sol-gel method; Analisis de la senal termoluminiscente en la hidroxiapatita sintetizada por el metodo sol gel

    Energy Technology Data Exchange (ETDEWEB)

    Mendoza A, D.; Gonzalez, P.R. [ININ, A.P. 18-1027, 11801 Mexico D.F. (Mexico); Lobato, M.; Rubio, E.; Rodriguez L, V. [Fac. de Ingenieria Quimica, BUAP, Av. San Claudio y 18 Sur, Col. San Manuel, 72570 Puebla (Mexico); Custodio, E. [Universidad Juarez Autonoma de Tabasco, DACB, Carr. Cunduacan-Jalpa Km. 1.5, 86680 Tabasco (Mexico)

    2004-07-01

    The physical properties of the ceramics are related with the chemical bonds and the crystalline structure, because the elements that constitute it can be united by ionic bonds or partially ionic giving a covalent character, this last causes that the outer layer is full of electrons. This property makes that the ceramic ones become interesting materials for thermoluminescent applications, as it demonstrates through the recent works presented on the hydroxyapatite that is a ceramic biomaterials that has shown an interesting thermoluminescent signal when being exposed to gamma radiation. In this sense, this work presents the thermoluminescent signal analysis induced by the UV and gamma radiation in a particular type of hydroxyapatite synthesized by sol gel method in which the temperature synthesis is varied. The final thermoluminescent sensitivity of materials is correlated with the crystalline degree, which is analysed through X-ray diffraction. (Author)

  15. General criteria for validation of dosimetry methods in the context of a quality system ISO / IEC 17025; Criterios generales sobre validacion de metodos de dosimetria en el marco de un sistema de calidad ISO/IEC 17025

    Energy Technology Data Exchange (ETDEWEB)

    Martin Garcia, R.; Navarro Bravo, T.

    2011-07-01

    The accreditation of a testing laboratory in accordance with ISO / IEC 17025 recognizes the technical competence of a laboratory to perform certain tests. One of the requirements of that rule states that laboratories must demonstrate that the methods used are valid and appropriate for the intended use and customer needs. This demonstration is accomplished through the process of validation of methods, defined in the rule it self as {sup c}onfirmation by examination and provision of objective evidence that the requirements for a particular purpose{sup .} The process of validating a test method should be well planned and documented, including the requirements under the applicable rules and criteria established by the laboratory to comply with these requirements.

  16. Contribution to the spectrographic determination of impurities in uranium by the carrier distillation method; Nuevas aportaciones a la determinacion espectrografica de impurezas en materiales de uranio por el metodo de distilacion fraccionada con portador

    Energy Technology Data Exchange (ETDEWEB)

    Capdevila, C

    1967-07-01

    The carrier distillation method for the determination of impurities in uranium has been modified in order to get a greater sensitivity. Electrodes 9.5 mm. diam. with a crater 7 mm. diam. and 10 mm. deep have been used, being the weigh of charge 300 mg.. The elements considered were: Al, As, B, Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Mo, Ni, P, Pb, Si, Sn, Ti and V, over the range 0.01 to 30 ppm. (Author) 13 refs.

  17. Environmental vigilance programmes of desalination plants. Development of an evaluations method of its application; Los Programas de Vigilancia Ambiental de las Instalaciones Desalinizadoras de Agua Marina. Desarrollo de un metodo de valoracion de su aplicacion

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz Arriaga, S.; Garcia Sanchez-Colomer, M.

    2008-07-01

    This article aims to develop a working methodology to assess the application of the measures designed to avoid, reduce and, if possible, remedy significant adverse effects, included in the Environmental Vigilance Programmes. the study is based on a practical case study of the building project, currently under development, of a desalination plant located in the Spanish Mediterranean coast. A collection of measures was selected to be fulfilled in any building project of a desalination plant, and thus the requirements derivates from them. Their analysis will allow to establish the level of fulfillment (regarding to the measures taken from the Environmental Vigilance Programme or the Declaration of Environmental Impact) and the evaluation (regarding to the measures taken from specialized bibliography) of the indicators implementation. This monitoring provides the supervisor of environmental issues with a valid tool to negotiate with the developer certain modifications, with the objective or improving the effectiveness of the measures described in the Environmental Vigilance Programme. (Author) 5 refs.

  18. Hydraulic conductivity obtained by instantaneous profile method using retention curve and neutron probes and Genuchten model; Condutividade hidraulica obtida pelo metodo do perfil instantaneo utilizando curva de retencao e sonda de neutrons e pelo modelo de Genuchten

    Energy Technology Data Exchange (ETDEWEB)

    Berretta, Ana Lucia Olmedo

    1999-07-01

    The hydraulic conductivity is one of the most important parameters to understand the movement of water in the unsaturated zone. Reliable estimations are difficult to obtain, once the hydraulic conductivity is highly variable. This study was carried out at 'Escola Superior de Agricultura Luiz de Queiroz', Universidade de Sao Paulo, in a Kandiudalfic Eutrudox soil. The hydraulic conductivity was determined by a direct and an indirect method. The instantaneous profile method was described and the hydraulic conductivity as a function of soil water content was determined by solving the Richards equation. Tensiometers were used to estimate the total soil water potential, and the neutron probe and the soil retention curve were used to estimate soil water content in the direct method. The neutron probe showed to be not adequately sensible to the changes of soil water content in this soil. Despite of the soil retention curve provides best correlation values to soil water content as a function of water redistribution time, the soil water content in this soil did not vary too much till the depth of 50 cm, reflecting the influence of the presence of a Bt horizon. The soil retention curve was well fitted by the van Genuchten model used as an indirect method. The values of the van Genuchten and the experimental relative hydraulic conductivity obtained by the instantaneous profile method provided a good correlation. However, the values estimated by the model were always lower than that ones obtained experimentally. (author)

  19. Method for determining the wedge angle from the daily measurements made with the measurement enabled devices DC6; Metodo para la determinacion del angulo de cuna a partir de las medidas diarias realizadas con el dispositio de medida QC6

    Energy Technology Data Exchange (ETDEWEB)

    Marques Fraguela, E.; Suero Rodrigo, M. A.

    2011-07-01

    The aim of this paper is to present a method for determining the angle of the wedges virtual electron linear accelerator (ALE) Siemens Primus, from the daily measurements made with the measurement system PTW-QC6Plus and found to be sufficiently sensitive to determine variations of {+-} 1 of this parameter. In addition, we study the behavior statistically CUFLE angle over a year.

  20. Contents evaluation of some essential and toxic elements in children and elders diet by neutron activation analysis; Avaliacao do conteudo de alguns elementos essenciais e toxicos em dietas de criancas e idosos pelo metodo de analise por ativacao com neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Maihara, Vera Akiko

    1997-12-31

    Essential and toxic elements in the 19 diet samples from pre-school children and 23 diet samples from elderly people, have been determined by neutron activation analysis. The diet samples were collected by duplicate portion method. A radiochemical separation procedure was developed and applied for determining Cd, Co, Cr, Fe, Mo, Sb, U, Th, W and Zn, based on retention of these elements in a Chelex-100 resin. In the case of As and Se, the procedure was based on retention in inorganic exchanger TDO (tin dioxide). The contents of proteins, lipids and carbohydrates were also analysed. The results have been presented and discussed 135 refs., 29 figs., 36 tabs.

  1. A polynomial analytical method for one-group slab-geometry discrete ordinates heterogeneous problems; Metodo analitico de aproximacao polinomial para problemas de ordenadas discretas em geometria Cartesiana unidimensional

    Energy Technology Data Exchange (ETDEWEB)

    Leal, Andre Luiz do Carmo

    2008-07-01

    In this work we evaluate polynomial approximations to obtain the transfer functions that appear in SGF auxiliary equations (Green's Functions) for monoenergetic linearly anisotropic scattering SN equations in one-dimensional Cartesian geometry. For this task we use Lagrange Polynomials in order to compare the numerical results with the ones generated by the standard SGF method applied to SN problems in heterogeneous domains. This work is a preliminary investigation of a new proposal for handling the transverse leakage terms that appear in the transverse-integrated one-dimensional SN equations when we use the SGF - exponential nodal method (SGF-ExpN) in multidimensional rectangular geometry. (author)

  2. Application of the Detrended Fluctuation Analysis method to the trajectory of the centre of pressure of the human body; Aplicacion del metodo Detrended Fluctuation Analysis a la trayectoria del centro de presion del cuerpo humano

    Energy Technology Data Exchange (ETDEWEB)

    Blazquez, M. T.; Anguiano, M.; Arias de Saavedra, F.; Lallena, A. M.; Carpena, P.

    2009-07-01

    The Detrended Fluctuation Analysis is a signal analyzing method which permits to study the correlation properties of the signal analyzed. This algorithm admits different variants which can be used to eliminate trends of different order existing in the signal. In this work we show the results obtained when two of these different variants, the so-called DFA-1 and DFA-2, are applied to the time series of the position and velocity of the centre of pressure of the human body in static conditions. The results show that the correlation exponents {alpha} obtained for each of the four types of analysis performed, depend on the scale studied. For the scales corresponding to large time intervals (above 35 s) the {alpha} values found in the four analyses coincide. (Author) 24 refs.

  3. An alternative method for increasing the effectiveness of Diesel engine performance according to the altitude; Un metodo alternativo de elevacion de la efectividad del funcionamento de los motores diesel en condiciones de altura

    Energy Technology Data Exchange (ETDEWEB)

    Lastra Espinoza, Luis A. [Universidad Nacional de Ingenieria, Lima (Peru). Facultad de Ingenieria Mecanica; Patrakhaltsev, Nicolai N. [Universidad de la Amistad de los Pueblos, Moscou (Russian Federation). Catedra de Motores Combinados

    1995-07-01

    The development of new methods of the compensating of Diesel motor's losses due to the altitude are still in force, even through the supercharged turbocharging is the most effective method. It is possible to compensate the loss due to the altitude by forcing the work process through the fuel-air ratio. This forcing consists of intensifying the formation of the mixture and combustion process using activators in the engine cylinders. (author)

  4. Windmills: selection method and results obtained by the Renewable Energy Center of UNESP - Guaratingueta Campus, Sao Paulo state, Brazil; Cata-vento: metodo de selecao e resultados obtidos pelo Centro de Energias Renovaveis da UNESP - Campus Guaratingueta

    Energy Technology Data Exchange (ETDEWEB)

    Moura, Luis Fernando Silva; Souza, Teofilo Miguel de [Universidade Estadual Paulista (UNESP), Guaratingueta, SP (Brazil). Centro de Energias Renovaveis], e-mail: teofilo@feg.unesp.br, e-mail: lfernandosm@uol.com.br

    2004-07-01

    Windmills are always a good option to promote irrigate in areas with adequate potential wind. Its correct selection can guarantee the enough water supply with minimum cost. Since April 2004 the Renewable Energy Center of UNESP - Campus Guaratingueta' has tested a commercial windmill with 18 blades rotor and 3,4 diameter meters, that in a area with approximately 3 m/s average wind speed, has been obtained a average daily 1500 water liters. This volume is enough to supply a small country state, however, it could be get with a smaller capacity machine, if this worked properly. (author)

  5. Dispersion of organoclays in polypropylene nanocomposites by ultrasound-assisted solution method; Estudo da dispersao de argilas organofilicas em nanocompositos de prolipropileno obtidos pelo metodo em solucao com auxilio de ultrassom

    Energy Technology Data Exchange (ETDEWEB)

    Bischoff, Eveline; Santos, Kelly Silva dos; Liberman, Susana Alcira; Mauler, Raquel Santos, E-mail: eve_bischoff@yahoo.com.br [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Inst. de Quimica

    2013-07-01

    Polypropylene nanocomposites PP/OMMT were prepared using two modified organic clays (C-15A and I-44P) and (PP-g-MA) as compatibilizer in the solution method using an ultrasound bath. The objective of this study was to understand the morphology of the nanocomposites and degree of clay dispersion in the polypropylene matrix, which are then correlated with the final properties. The morphology of nanocomposites was evaluated by X-ray Diffraction (XRD) and Transmission Electron Microscopy (TEM). The dynamic mechanical properties and thermal properties were measured by Dynamic Mechanical Analysis (DMA) and Differential Scanning Calorimetry (DSC). Statistical analyses of the transmission images were made in order to obtain the aspect ratio (length/thickness) of the clay particles. (author)

  6. Coupling between the differential and perturbation theory methods for calculating sensitivity coefficients in nuclear transmutation problems; Acoplamento entre os metodos diferencial e da teoria da perturbacao para o calculo dos coeficientes de sensibilidade em problemas de transmutacao nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Rossi, Lubianka Ferrari Russo

    2014-07-01

    The main target of this study is to introduce a new method for calculating the coefficients of sensibility through the union of differential method and generalized perturbation theory, which are the two methods generally used in reactor physics to obtain such variables. These two methods, separated, have some issues turning the sensibility coefficients calculation slower or computationally exhaustive. However, putting them together, it is possible to repair these issues and build a new equation for the coefficient of sensibility. The method introduced in this study was applied in a PWR reactor, where it was performed the sensibility analysis for the production and {sup 239}Pu conversion rate during 120 days (1 cycle) of burnup. The computational code used for both burnup and sensibility analysis, the CINEW, was developed in this study and all the results were compared with codes widely used in reactor physics, such as CINDER and SERPENT. The new mathematical method for calculating the sensibility coefficients and the code CINEW provide good numerical agility and also good efficiency and security, once the new method, when compared with traditional ones, provide satisfactory results, even when the other methods use different mathematical approaches. The burnup analysis, performed using the code CINEW, was compared with the code CINDER, showing an acceptable variation, though CINDER presents some computational issues due to the period it was built. The originality of this study is the application of such method in problems involving temporal dependence and, not least, the elaboration of the first national code for burnup and sensitivity analysis. (author)

  7. Uncertainty Evaluation and Influence of Gran Size to Determine PAHs in a Contaminated Soil; Influencia del Tamano de Particula de un Suelo Contaminado en las Incertidumbres Asociadas al Metodo de Determinacion de PAHs

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Alonso, S.; Perez Pastor, R. M.; Escolano Segoviano, O.; Garcia Frutos, F. J.

    2007-07-20

    An evaluation of uncertainty associated to PAH determination in a contaminated soil is presented. The work was focused to measure the influence of grain size on concentration deviations and give a measure of result confidence of PAHs in the gasworks contaminated soil. This study was performed in the frame of the project 'Assessment of natural remediation technologies for PAHs in contaminated soils'(Spanish Plan Nacional I+D+i, CTM 2004-05832-CO2-01). This paper is presented as follows: A brief introduction which describes the main uncertainty contributions associated to chromatographic analysis. Afterwards, a statistic calculation was performed to measure each uncertainty component. Finally, a global uncertainty was calculated and the influence of grain size and distribution of compounds according to volatility was evaluated. (Author) 10 refs.

  8. Jaws calibration method to get a homogeneous distribution of dose in the junction of hemi fields; Metodo de calibracion de mandibulas para conseguir una distribucion homogenea de dosis en la zona de union de hemicampos

    Energy Technology Data Exchange (ETDEWEB)

    Cenizo de Castro, E.; Garcia Pareja, S.; Moreno Saiz, C.; Hernandez Rodriguez, R.; Bodineau Gil, C.; Martin-Viera Cueto, J. A.

    2011-07-01

    Hemi fields treatments are widely used in radiotherapy. Because the tolerance established for the positioning of each jaw is 1 mm, may be cases of overlap or separation of up to 2 mm. This implies heterogeneity of doses up to 40% in the joint area. This paper presents an accurate method of calibration of the jaws so as to obtain homogeneous dose distributions when using this type of treatment. (Author)

  9. Dynamical study of the Darrieus-type turbine runners by using finite element method; Estudo da dinamica de turbinas hidraulicas mare-motrizes do tipo Darrieus atraves do metodo dos elementos finitos

    Energy Technology Data Exchange (ETDEWEB)

    Sena, Manoel Jose dos Santos; Mesquita, Andre Luiz Amarante [Para Univ., Belem, PA (Brazil). Dept. de Engenharia Mecanica. Grupo de Turbomaquinas]. E-mail: gtdem@ufpa.br

    2000-07-01

    The purpose of this work is describe the implementation of a finite element model for dynamic response analysis of Darrieus-type turbine runners. A fluid-structure coupling is be used to put in evidence some aspects of the rotor-water interaction. The rotating system fixed to the rotor will be used when writing the equations governing the system. A procedure using the ANSYS Parametric Design Language is discussed and some results obtained for the free-free configuration are shown. (author)

  10. Molecular structure determination of cyclooctane by Ab Initio and electron diffraction methods in the gas phase; Determinacao da estrutura molecular do ciclooctano por metodos Ab Initio e difracao de eletrons na fase gasosa

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Wagner B. de [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Dept. de Quimica

    2000-10-01

    The determination of the molecular structure of molecules is of fundamental importance in chemistry. X-rays and electron diffraction methods constitute in important tools for the elucidation of the molecular structure of systems in the solid state and gas phase, respectively. The use of quantum mechanical molecular orbital ab initio methods offer an alternative for conformational analysis studies. Comparison between theoretical results and those obtained experimentally in the gas phase can make a significant contribution for an unambiguous determination of the geometrical parameters. In this article the determination for an unambiguous determination of the geometrical parameters. In this article the determination of the molecular structure of the cyclooctane molecule by electron diffraction in the gas phase an initio calculations will be addressed, providing an example of a comparative analysis of theoretical and experimental predictions. (author)

  11. The use of genetic algorithms with niching methods in nuclear reactor related problems; A utilizacao dos metodos de nichos dos algoritmos geneticos na otimizacao de problemas de reatores nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Sacco, Wagner Figueiredo

    2000-03-01

    Genetic Algorithms (GAs) are biologically motivated adaptive systems which have been used, with good results, in function optimization. However, traditional GAs rapidly push an artificial population toward convergence. That is, all individuals in the population soon become nearly identical. Niching Methods allow genetic algorithms to maintain a population of diverse individuals. GAs that incorporate these methods are capable of locating multiple, optimal solutions within a single population. The purpose of this study is to test existing niching techniques and two methods introduced herein, bearing in mind their eventual application in nuclear reactor related problems, specially the nuclear reactor core reload one, which has multiple solutions. Tests are performed using widely known test functions and their results show that the new methods are quite promising, specially in real world problems like the nuclear reactor core reload. (author)

  12. A hydrothermal economic dispatch model for the energy markets using the interior point method; Um modelo de despacho economico hidrotermico para os mercados de energia utilizando o metodo de pontos interiores

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Leandro L.H.; Silva, Alessandro L. da; Vergilio, Andre H.B.; Nepomuceno, Leonardo [Universidade Estadual Paulista (UNESP), Bauru, SP (Brazil). Dept. de Engenharia Eletrica], Emails: leandroluiz@ymail.com, alessandrolopessilva@uol.com.br, andrevergilio@yahoo.com.br, leo@feb.unesp.br; Cicogna, Marcelo Augusto [Anhanguera Educacional S.A. (Brazil)], E-mail: marcelo.cicogna@unianhanguera.edu.br,

    2009-07-01

    This paper aims to propose a model of economic dispatch for the problem representation of the auction in pool markets for systems with generation predominantly hydraulic. In the dispatch models described in the literature, only the agents of thermal generation participate in the auction pool. This is due to the fact that it have not been proposed in the literature yet a suitable model for representation of the cost structure of hydraulic generators. In this work is proposed the function of opportunity cost of hydrogeneration, which establishes a framework of 'cost' of hydraulic generation, based on losses in the process of hydroelectric generation. It is also studied the feasibility that both agents on the hydraulic and thermal generators can bidding in the pool. The approach to solving the problem involves the method of primal-dual logarithmic barrier. The results show that using the function of opportunity cost for hydroelectric plants is important for the system energy optimization as a whole, but its use for the representation of the bids of the hydraulic agents still needs further deepening search.

  13. Monte Carlo method for dose calculation due to oral X-rays; Coeficientes de conversao para calculo de doses devidos a radiografias odontologicas utilizando o metodo de Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Loureiro, Eduardo Cesar de Miranda

    1998-06-01

    The increasing utilization of oral X-rays, especially in youngsters and children, calls for the assessment of equivalent doses in their organs and tissues. With this purpose, a Monte Carlo code was adapted to simulate an X-ray source irradiating phantoms of the MIRD-5 type with different ages (10, 15 and 40 years old) to calculate the conversion coefficients which transform the exposure at skin to equivalent doses at several organs and tissues of interest. In order to check the computer program, simulations were performed for adult patients using the original code (ADAM.FOR developed at the GSF-Germany) and the adapted program (MCDRO.PAS). Good agreement between results obtained with both codes was observed. Irradiations of the incisive, canine and molar teeth were simulated. The conversion factors were calculated for the following organs and tissues: thyroid, active bone narrow (head and whole body), bone (facial skeleton, cranium and whole body), skin (head and whole body) and crystalline. Based on the obtained results, it follows that the younger the patient and the larger the field area, the higher the dose in assessed organs and tissues. The variation of the source-skin distance does not change the conversion coefficients. On the other hand, the increase in the voltage applied to the X-ray tube causes an increase in the calculated conversion coefficients. (author)

  14. Numerical simulation methods applied to injection and storage of CO{sub 2} in saline aquifers; Metodos de simulacion numerica aplicados a la inyeccion y almacenamiento de CO{sub 2} en formaciones salinas

    Energy Technology Data Exchange (ETDEWEB)

    Arjona Garcia-Borreguero, J.; Rodriguez Pons-Esparver, R.; Iglesias Lopez, A.

    2015-07-01

    One of the Climate Change mitigation proposals suggested by the IPCC (Intergovernmental Panel on Climate Change) in its Synthesis Report 2007 involves the launch of applications for capturing and storing carbon dioxide, existing three different geological structures suitable for gas storage: oil and gas depleted reservoirs, useless coal layers and deep saline structures. In case of deep saline structures, the main problem to prepare a study of CO{sub 2} storage is the difficulty of obtaining geological data for some selected structure with characteristics that could be suitable for injection and gas storage. According to this situation, the solution to analyze the feasibility of a storage project in a geological structure will need numerical simulation from a 3D terrain model. Numerical methods allow the simulation of the carbon dioxide filling in saline structures from a well, used to inject gas with a particular flow. This paper presents a methodology to address the modeling and simulation process of CO{sub 2} injection into deep saline aquifers. (Author)

  15. Validation of methods to measure uranium isotopes using magnetic sector mass spectrometry with inductively coupled plasma source; Validacion de metodos para medir isotopos de uranio usando espectrometria de masas de sector magnetico con fuente de plasma acoplado inductivamente

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez M, H. [Universidad del Centro de Mexico, Capitan Caldera 75, Col. Tequixquiapan, 78250 San Luis Potosi, SLP (Mexico); Rios L, M. J. [Universidad Autonoma de San Luis Potosi, Facultad de Enfermeria y Nutricion, Unidad de Posgrado, Av. Nino Artillero 130, 78210 San Luis Potosi, SLP (Mexico); Romero G, E. T., E-mail: hector.hernandez520@gmail.com [ININ, Departamento de Quimica, Laboratorio Forense Nuclear, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2017-10-15

    The mass spectrometry technique with inductively coupled plasma source (Icp-Ms) has been widely used to measure isotopic ratios of elements toxic to human health. Reason for which, in this work several measurement methods for the analysis of uranium isotopes in different matrices were implemented using magnetic sector mass spectrometry with inductively coupled plasma source (Icp-SFMS). Groundwater, sediment, soil and urine were the matrices analyzed, which were supplied by intercomparison tests conducted by the IAEA and Association for the Promotion of Quality Control of Medical Biology Analysis in Radio-toxicology. The procedures used in the treatment of soil, sediment and water samples were based on US EPA methods. In the case of the urine sample, the preparation was rapid (1:20 dilution). The average of the results obtained in yield of each matrix was 94, 71, 72 and 78% for water, urine, soil and sediment respectively. In addition, the precision in terms of standard relative deviation was less than 5% and the accuracy was less than 4%. In conclusion, the Icp-SFMS is a very sensitive technique for measuring isotopes of U in different matrices. However, careful tuning is necessary, especially in the mass regions of interest 234, 235 and 238 if an external quantification is considered using natural U solutions. (Author)

  16. Measurement of unattached aerosols of {sup 222} Rn progeny by means of an electrostatic deposition method; Medicion de la fraccion no unida a aerosoles de la progenie de {sup 222} Rn mediante un metodo de deposicion electrostatica

    Energy Technology Data Exchange (ETDEWEB)

    Canoba, Analia C; Lopez, Fabio O [Autoridad Regulatoria Nuclear, Buenos Aires (Argentina)

    2001-07-01

    A method for the measurement of unattached radon progeny based on its electrostatic deposition onto wire screens, using only one pump, has been implemented and calibrated. The importance of being able of making use of this method is related with the special radiological significance that has the unattached fraction of the short-lived radon progeny. Because of this, the assesment of exposure could be directly related to dose with far greater accuracy than before.The advantages of this method are its simplicity, even with the tools needed for the sample collection, as well as the measurement instruments used. Also, the suitability of this method is enhanced by the fact that it can effectively be used with a simple measuring procedure such as the Kusnetz method. (author)

  17. Measurement of unattached radon progeny based in electrostatic deposition method; Medicion de la fraccion no unida a aerosoles de la progenie de {sup 222}Rn mediante un metodo de deposicion electrostatica

    Energy Technology Data Exchange (ETDEWEB)

    Canoba, A C; Lopez, F O

    1999-07-01

    A method for the measurement of unattached radon progeny based on its electrostatic deposition onto wire screens, using only one pump, has been implemented and calibrated. The importance of being able of making use of this method is related with the special radiological significance that has the unattached fraction of the short-lived radon progeny. Because of this, the assessment of exposure could be directly related to dose with far greater accuracy than before. The advantages of this method are its simplicity, even with the tools needed for the sample collection, as well as the measurement instruments used. Also, the suitability of this method is enhanced by the fact that it can effectively be used with a simple measuring procedure such as the Kusnetz method. (author)

  18. Evaluation of the shield calculation adequacy of radiotherapy rooms through Monte Carlo Method and experimental measures; Avaliacao da adequacao do calculo de blindagens de salas de radioterapia atraves do metodo de Monte Carlos e medidas experimentais

    Energy Technology Data Exchange (ETDEWEB)

    Meireles, Ramiro Conceicao

    2016-07-01

    The shielding calculation methodology for radiotherapy services adopted in Brazil and in several countries is that described in publication 151 of the National Council on Radiation Protection and Measurements (NCRP 151). This methodology however, markedly employs several approaches that can impact both in the construction cost and in the radiological safety of the facility. Although this methodology is currently well established by the high level of use, some parameters employed in the calculation methodology did not undergo to a detailed assessment to evaluate the impact of the various approaches considered. In this work the MCNP5 Monte Carlo code was used with the purpose of evaluating the above mentioned approaches. TVLs values were obtained for photons in conventional concrete (2.35g / cm{sup 3}), considering the energies of 6, 10 and 25 MeV, respectively, first considering an isotropic radiation source impinging perpendicular to the barriers, and subsequently a lead head shielding emitting a shaped beam, in the format of a pyramid trunk. Primary barriers safety margins, taking in account the head shielding emitting photon beam pyramid-shaped in the energies of 6, 10, 15 and 18 MeV were assessed. A study was conducted considering the attenuation provided by the patient's body in the energies of 6,10, 15 and 18 MeV, leading to new attenuation factors. Experimental measurements were performed in a real radiotherapy room, in order to map the leakage radiation emitted by the accelerator head shielding and the results obtained were employed in the Monte Carlo simulation, as well as to validate the entire study. The study results indicate that the TVLs values provided by (NCRP, 2005) show discrepancies in comparison with the values obtained by simulation and that there may be some barriers that are calculated with insufficient thickness. Furthermore, the simulation results show that the additional safety margins considered when calculating the width of the primary barrier of radiotherapy rooms are conservative. They also show that the attenuation provided by the patient's body decreases with increased energy, with the highest attenuation being 0.54, for the energy of 6 MeV. (author)

  19. Catalyst synthesis PD/SiO{sub 2} and PD/C by irradiation microwave method; Sintese de catalisador PD/SiO{sub 2} e PD/C por metodo de irradiacao micro-ondas

    Energy Technology Data Exchange (ETDEWEB)

    Sant' Anna, L.S.; Franceschi, E.; Egues, S.; Santos, M.L.; Dariva, C.; Borges, G.R., E-mail: leonardo-se@hotmail.com [Universidade Tiradentes (UNIT), Aracaju, SE (Brazil). Nucleo de Estudos em Sistemas Coloidais

    2016-07-01

    The synthesis of nanoparticulate materials has been developed over the years, in order to propose new routes or routes more efficient in the process. The application of microwave irradiation applied in this work allowed to show that metal catalysts may be generated in a faster reaction time compared to conventional mechanical agitation techniques. Catalysts using palladium acetate (OAc){sub 2} supported on charcoal and commercial silica were synthesized. The solvent used for the preparation was 40 ml of ethanol at a temperature of 100 ° C and 300 W power. The synthesis time was 2 to 5 minutes. The synthesized material was calcined and characterized by ICP, XRD, TEM and BET obtained metal content ranged from 1.1 to 4.1% of the metal support. The particle size was between 7 and 9 nm. The surface areas of the carriers were reduced on its surface due to the metal impregnation. (author)

  20. SIMULATION OF RAINFALL AND SEEPAGE FLOW ON UNSATURATED SOIL BY A SEEPAGE-DEFORMATION COUPLED METHOD SIMULACIÓN DE LLUVIA E INFILTRACIÓN EN SUELOS PARCIALMENTE SATURADOS USANDO UN METODO ACOPLADO INFILTRACIÓN-DEFORMACIÓN

    Directory of Open Access Journals (Sweden)

    Edwin García-Aristizábal

    2012-06-01

    Full Text Available This paper presents an application for the analysis of structures formed by unsaturated layered soils subjected to rainfall and seepage flow; the results are part of a current research project on rainfall infiltration. A three-phase coupled infiltration-deformation method for unsaturated soil was used for the numerical analysis. The effects of the water permeability and horizontal drainage on the distribution of seepage flow velocities, saturation, and generation of deformations for an unsaturated layered embankment were investigated. The results show that the generation of deformation on the embankment surface highly depends on the water permeability of the soil. In addition, through horizontal drainage simulations, the advantage of this type of solution for decreasing the pore water pressures on the back of the slope embankment, thus avoiding local failure (erosion, is shown.Este artículo presenta una aplicación para el análisis de estructuras compuestas por suelos parcialmente saturados que están sometidas al efecto de la lluvia y la infiltración; los resultados hacen parte de una investigación en curso relacionada con infiltración de aguas lluvias. Para los análisis numéricos se utilizó un método trifásico acoplado de infiltración-deformación. Se investigaron los efectos que tienen la permeabilidad y el drenaje lateral en la distribución de los vectores de velocidad de infiltración, la saturación y la generación de deformaciones para un terraplén estratificado y parcialmente saturado. Los resultados muestran que la generación de deformación en el talud del terraplén depende, en gran parte, de la permeabilidad del suelo. Adicionalmente, por medio de simulación de drenes horizontales, se muestra la ventaja de este tipo de solución para disminuir las presiones de poros internas en el talud del terraplén, evitando la falla local (erosión.

  1. Analysis of oil content in sunflower seeds with nuclear magnetic ressonance and `SOXHLET` methods; Determinacao do teor de oleo em sementes de girassol pelos metodos de ressonancia magnetica nuclear e soxhlet

    Energy Technology Data Exchange (ETDEWEB)

    Ungaro, Maria Regina Goncalves [Instituto Agronomico de Campinas, SP (Brazil). Secao de Oleaginosas; Toledo, Nilva Maria Prestes de [Instituto Agronomico de Campinas, SP (Brazil). Secao Tecnica Experimental e Calculo; Teixeira, Joao Paulo Feijao [Instituto Agronomico de Campinas, SP (Brazil). Secao de Fitoquimica; Suassuna Filho, Jose [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil). Dept.de Fisica

    1993-12-31

    Individual and group of seeds of some sunflower populations were utilized in order to evaluate the feasibility of oil content evaluations by the Nuclear Magnetic Resonance method (NMR). Correlation analysis with the extractive method (Soxhlet) was performed. The results showed that: the oil in the seeds behaved like a liquid in the NMR analysis; there was a high and positive correlation (r = 0,93) between NMR and Soxhlet; there was no correlation between seed weight and oil content; the observed variability in oil content among seeds of a plant were higher than between plants of a population; these values indicate the importance of making individual analysis of oil content by the NMR method for the sunflower breeding for oil content. (author) 7 refs., 2 figs., 4 tabs.

  2. Seed prepare for oil content determination by NMR method in six cotton varieties; Preparo de sementes para determinacao do teor de oleo pelo metodo de RMN em seis variedades de algodoeiro

    Energy Technology Data Exchange (ETDEWEB)

    Gondim-Tomaz, Rose Marry Araujo; Erismann, Norma de Magalhaes; Sabino, Nelson Paulieri; Kondo, Julio Isao; Cia, Edivaldo; Azzini, Anisio [Instituto Agronomico de Campinas, SP (Brazil). Centro de Algodao e Fibrosas Diversas]. E-mail: gondim@cec.iac.br; Soave, Daise [Instituto Agronomico de Campinas, SP (Brazil). Centro de Genetica, Biologia Molecular e Fitoquimica

    1998-07-01

    Three comparative methods (chemical seed-delinting with sulphuric acid solution, flaming and seed with linter) to prepare cotton seeds for oil determination by the Nuclear Magnetic Resonance (NMR) technique were considered. The chemical treatment with sulphuric acid was the best as long the linter interference was eliminated. The seed oil contents were determined by the NMR method in six cotton varieties from the national variety test. The IAPAR (Instituto Agronomico do Parana) 71 PR3 and IAC (Instituto Agronomico de Campinas) 20 varieties presented the highest oil content followed by the CNPA 7H, CS 50, IAC 22 and CNPA Precoce 2. (author)

  3. Calibration method for a in vivo measurement system using mathematical simulation of the radiation source and the detector; Metodo de calibracao de um sistema de medida in vivo atraves da simulacao matematica da fonte de radiacao e do detector

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, John

    1998-12-31

    A Monte Carlo program which uses a voxel phantom has been developed to simulate in vivo measurement systems for calibration purposes. The calibration method presented here employs a mathematical phantom, produced in the form of volume elements (voxels), obtained through Magnetic Resonance Images of the human body. The calibration method uses the Monte Carlo technique to simulate the tissue contamination, the transport of the photons through the tissues and the detection of the radiation. The program simulates the transport and detection of photons between 0.035 and 2 MeV and uses, for the body representation, a voxel phantom with a format of 871 slices each of 277 x 148 picture elements. The Monte Carlo code was applied to the calibration of in vivo systems and to estimate differences in counting efficiencies between homogeneous and non-homogeneous radionuclide distributions in the lung. Calculations show a factor of 20 between deposition of {sup 241} Am at the back compared with the front of the lung. The program was also used to estimate the {sup 137} Cs body burden of an internally contaminated individual, counted with an 8 x 4 Nal (TI) detector and an {sup 241} Am body burden of an internally contaminated individual, who was counted using a planar germanium detector. (author) 24 refs., 38 figs., 23 tabs.

  4. Evaluation of fracture toughness in dental ceramics using indentation and SEVNB (Single Edge V-Notched Beam)-method; Avaliacao da tenacidade a fratura de ceramicas dentarias atraves do metodo de entalhe - SEVNB (Single Edge V-Notched Beam)

    Energy Technology Data Exchange (ETDEWEB)

    Santos, L.A.; Santos, C.; Souza, R.C.; Ribeiro, S. [Universidade de Sao Paulo (DEMAR/EEL/USP), Lorena, SP (Brazil). Escola de Engenharia de Lorena. Dept. de Engenharia de Materiais. Polo Urbo-Industrial; Strecker, K. [Universidade Federal de Sao Joao del-Rei (DME/UFSJ), MG (Brazil). Dept. de Materiais Eletricos; Oberacker, R. [Karlsruhe Univ. (Germany)

    2009-07-01

    In this work, the fracture toughness of different ceramics based on Al{sub 2}O{sub 3} and ZrO{sub 2} were evaluated using, comparatively two methods, Vickers indentation and SEVNB (Single Edge V-Notched Beam) method. Al{sub 2}O{sub 3}, ZrO{sub 2}(3%Y{sub 2}O{sub 3}) micro-particled and ZrO{sub 2}(3%Y{sub 2}O{sub 3}) nanometric, ZrO{sub 2}-Al{sub 2}O{sub 3} and Al{sub 2}O{sub 3}-ZrO{sub 2} composites were sintered at different temperatures. Samples were characterized by relative density, X-ray diffraction, SEM, and mechanical evaluation by hardness, bending strength and fracture toughness obtained by ickers indentation and SEVNB-method. The results were presented comparing the densification and microstructural results. Furthermore, the advantages and limitations of each method were discussed. (author)

  5. Performance analysis of covered conductors and aerial bundled cables by the finite elements method; Analise de desempenho de cabos cobertos e pre-reunidos pelo metodo dos elementos finitos

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Joao Jose dos Santos

    1996-12-31

    The covered conductors and the aerial bundled cables (abc) for overhead distribution systems 15 kV systems, has been a good solution for the main brazilian electrical utilities when applied in areas with to limited space on poles and to satisfy the performance claimed in tree areas or narrow streets, focusing people safety and electrical service continuity. Otherwise, in this work it is presented that these cables show failures that can be related to the solid isolants used. It is showed the laboratory tests results to characterize its thermal and electric behaviour and an application of the Finite Element Method through the software Flux 2 d was done. The results obtained showed the requirements to be demanded through the specification and proposals elements to change the standard. (author) 57 refs., 20 figs., 73 tabs.

  6. Validation of uncertainty of weighing in the preparation of radionuclide standards by Monte Carlo Method; Validacao da incerteza de pesagens no preparo de padroes de radionuclideos por Metodo de Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Cacais, F.L.; Delgado, J.U., E-mail: facacais@gmail.com [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Loayza, V.M. [Instituto Nacional de Metrologia (INMETRO), Rio de Janeiro, RJ (Brazil). Qualidade e Tecnologia

    2016-07-01

    In preparing solutions for the production of radionuclide metrology standards is necessary measuring the quantity Activity by mass. The gravimetric method by elimination is applied to perform weighing with smaller uncertainties. At this work is carried out the validation, by the Monte Carlo method, of the uncertainty calculation approach implemented by Lourenco and Bobin according to ISO GUM for the method by elimination. The results obtained by both uncertainty calculation methods were consistent indicating that were fulfilled the conditions for the application of ISO GUM in the preparation of radioactive standards. (author)

  7. Two media method for linear attenuation coefficient determination of irregular soil samples; Metodo dos dois meios para a determinacao do coeficiente de atenuacao linear de amostras irregulares de solos

    Energy Technology Data Exchange (ETDEWEB)

    Vici, Carlos Henrique Georges

    2004-07-01

    In several situations of nuclear applications, the knowledge of gamma-ray linear attenuation coefficient for irregular samples is necessary, such as in soil physics and geology. This work presents the validation of a methodology for the determination of the linear attenuation coefficient ({mu}) of irregular shape samples, in such a way that it is not necessary to know the thickness of the considered sample. With this methodology irregular soil samples (undeformed field samples) from Londrina region, north of Parana were studied. It was employed the two media method for the {mu} determination. It consists of the {mu} determination through the measurement of a gamma-ray beam attenuation by the sample sequentially immersed in two different media, with known and appropriately chosen attenuation coefficients. For comparison, the theoretical value of {mu} was calculated by the product of the mass attenuation coefficient, obtained by the WinXcom code, and the measured value of the density sample. This software employs the chemical composition of the samples and supplies a table of the mass attenuation coefficients versus the photon energy. To verify the validity of the two media method, compared with the simple gamma ray transmission method, regular pome stone samples were used. With these results for the attenuation coefficients and their respective deviations, it was possible to compare the two methods. In this way we concluded that the two media method is a good tool for the determination of the linear attenuation coefficient of irregular materials, particularly in the study of soils samples. (author)

  8. The two means method for the attenuation coefficient determination of archaeological ceramics from the North of Parana; Metodo dos dois meios para a determinacao do coeficiente de atenuacao de ceramicas arqueologicas do norte do Parana

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Richard Maximiliano Cunha e

    1998-12-31

    This work reports an alternative methodology for the linear attenuation coefficient determination ({mu} {rho}) of irregular form samples, in such a way that is not necessary to consider the sample thickness. With this methodology, indigenous archaeological ceramics fragments from the region of Londrina, north of Parana, were studied. These ceramics fragments belong to the Kaingaing and Tupiguarani traditions. The equation for the {mu} {rho} determination employing the two mean method was obtained and it was used for {mu} {rho} determination by the gamma ray beam attenuation if immersed ceramics, by turns, in two different means with known linear attenuation coefficient. By the other side, {mu} theoretical value was determined with the XCOM computer code. This code uses as input the ceramics chemistry composition and provides an energy versus mass attenuation coefficient table. In order to validate the two mean method validation, five ceramics samples of thickness 1.15 cm and 1.87 cm were prepared with homogeneous clay. Using these ceramics, {mu} {rho} was determined using the attenuation method, and the two mean method. The result obtained for {mu} {rho} and its respective deviation were compared for these samples, for the two methods. With the obtained results, it was concluded that the two means method is good for the linear attenuation coefficient determination of materials of irregular shape, what is suitable, specially, for archaeometric studies. (author) 25 refs., 29 figs., 28 tabs.

  9. Analysis of Bone Meal (NIST 1486) and Bone Ash (NIST 1400) reference materials by neutron activation method; Analise de materiais de referencia Bone Meal (NIST 1486) e Bone Ash (NIST 1400) pelo metodo de ativacao com neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Takata, Marcelo K.; Saiki, Mitiko [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil); Borelli, Aurelio [Sao Paulo Univ., SP (Brazil). Faculdade de Medicina

    1999-11-01

    In this work instrumental neutron activation analysis has been applied to determine Ba, ca, Cl, Cr, fe, Mg, Mn, Na, P, Sb, Sc, Sr and Zn in two biological reference materials NIST 1486 Bone Meal and NIST 1400 Bone Ash. The purpose of this work was to evaluate the precision and the accuracy of the results as well as to give a contribution to certificate these materials. Interferences found in the determination of some elements were also discussed. (author) 8 refs., 4 tabs.

  10. Development of and horizontal seams wining system by means of galleries and chambers; Demostracion de un Sistema de Explotacion de Capas Horizontales por el Metodo de Pilares y Galerias Trazadas Integramente con Maquinas de Ataque Puntual

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    The project Development of an horizontal seams wining system by means of galleries and chambers aimed on the solution of a mining problem kept unresolved during the last 35 years in Carrasconte mine, owned by the society Minero Siderurgica de Ponferrada, in the coal yield of Villablino, Leon, Spain. The problem was a horizontal seam, with a width from 2,5 to 3,5 m, with two specific characteristics; one, roof and floor extremely rigid, with a 30 m sandstone stratum by roof that practically could highly restrict the long wall face conventional system, and the other, an intercalation of shale with a width of 1,2 m and a hardness of near 400 kg/cm2 that required a suitable winning system. By means of investigation with galleries carried out by continuous miners the real width of shale intercalation was stated, an then suitable systems adopted as this width varied. So, short wall faces in areas with minimum shale were disposed, and in t areas with maximum shale width, two long wall faces each one in each different vein were designed. At the end, the borders of reserves were recovered by the conventional system of galleries and chambers. This development project has allowed to recover more than a million tons in three years by systems suitable to the different conditions of the seam. (Author)

  11. Method to Solve the Problem of the Radioactivity Detection in Environmental Samples. Characteristic Limits; Metodos para la Resolucion del Problema de la Detecfcion de Radiactividad en Muestras Ambientales. Limites Caracteristicos

    Energy Technology Data Exchange (ETDEWEB)

    Gasco, C.; Martinez, M.; Heras, M.

    2009-07-21

    The problem of the detection or when the radioactivity can be considered as higher than the background using different measurement techniques has been the objective of several statistical studies and controversies. The detection limit and the critical limit were studied by Currie in year 1968 and used by radiochemistry laboratories considering different ways of calculation that introduced confusion and not correct implementations. In the last few years, and due to the increasing number of standardization processes on the field of radioactivity and accreditation, several international institutions have chosen to unify the criteria for using common determination of detection limits. The most used methods are those developed by MARLAP and International Standard Organization ISO (Standard-11929). In this report are summarised both standards doing a comparative study and giving some examples of how to apply these limits. In same cases, little differences in the uncertainty calculation have been observed but the final results have been concordant. A deeply study of these standards can be done consulting the web page of the American Labs that developed MARLAP or buying the original ISO standard ISO-11929 recently approved (2009). (Author) 17 refs.

  12. Adapting winning methods in Spanish coal for integration into the EEC. Proceso de adaptacion de los metodos de explotacion en la mineria de carbon espanola, con motivo de la integracion en la CEE

    Energy Technology Data Exchange (ETDEWEB)

    Madera, R.; Luque, V.

    1986-01-01

    The winning methods used in a coal mine depend upon a series of factors which can be divided into two large groups: - geological and mining conditions of the coalfields, including smaller zones within each coalfield; structural, legal, administrative and organisational factors. In order to draw comparisons and analyse the differences, the present situation in EEC countries is first described before going on to Spain and Asturias in particular.

  13. Optimizing the mercury mass measurement in industrial electrolytic cells by the radio-tracer method at ININ; Optimizacion de la medicion de masa de mercurio en celdas electroliticas industriales por el metodo de radiotrazado en el ININ

    Energy Technology Data Exchange (ETDEWEB)

    Valle R, J.; Angeles C, A., E-mail: Ing.valle.r@hotmail.com [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2014-10-15

    One method used in the production of chlorine and sodium is the use of electrolytic cells for the separation of chlorine and sodium from the brine; the industries apply very intense electromagnetic fields in this process. The electrolytic cells use mercury as electrode. In a chlorine production plant inventories are determined by total amount of mercury in the plant annually, since mercury losses are large and a very important parameter is to control the mass of mercury for it is necessary to measure with great precision the losses made. There are several methods to determine the mass of mercury ranging from take samples and weigh, but this involves continuous interruption of the process creating downtimes which in turn represent economic losses giving a result delimiting productivity for the industrial sector. An alternative and attractive method is to use a radioactive tracer whose principle has a similar behavior to study objective. The inert mercury has to be neutron activated in a nuclear reactor to having the characteristics of a tracer; the result makes one of the isotopes of mercury. The tracer is transported taking into account the recommendations of the Comision Nacional de Seguridad Nuclear y Salvaguardias (Mexico), then it is injected into the electrolytic cells mixing with the mercury in the system. By a relative radioactivity measurement and one sample by gamma spectrometry per interest cell, the mass of mercury without stopping the process is obtained. For optimal use of radio-tracer method must be taken into account as important features: irradiation time of mercury, counting conditions, vial geometry, sample volume, sample cells, mixing time and half-life of the tracer. (Author)

  14. Comparison in the determination of absorbed dose by biological and physical methods to patients in treatment of cardiac intervention; Comparacion en la determinacion de dosis absorbida por metodos biologicos y fisicos a pacientes en tratamiento de intervencionismo cardiaco

    Energy Technology Data Exchange (ETDEWEB)

    Guerrero C, C.; Arceo M, C., E-mail: citlali.guerrero@inin.gob.mx [ININ, Departamento de Biologia, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2014-10-15

    The use of less invasive procedures, lower risk and quick recovery as cardiac intervention have proven to be an efficient alternative to reestablish the correct bloodstream of the patient. In this case the patient is subjected to values of absorbed dose above to which is subjected in a study with X-rays for medical diagnosis, and this can cause radiation injuries to the skin. The target organ, in this case can be exposed to doses of 2 Gy above. Different methods to estimate the dose were use, physical by Radiochromic film, as biological by dicentric analysis. Both methods provided additional information demonstrating thus the risk in the target organ and the patient. The most reliable biological indicator of exposure to ionizing radiation is the study of chromosomal aberrations, specifically dicentric in human lymphocytes. This test allowed establishing the exposure dose depending of the damage. (Author)

  15. Structural analysis of a carbonated hydroxyapatite by the Rietveld method using different profile functions; Analise estrutural de uma hidroxiapatita carbonatada pelo metodo de Rietveld aplicando funcoes de perfil diferentes

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Jorge C. de [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Dept. de Matematica], e-mail: jcaraujo@iprj.uerj.br; Moreira, Elizabeth L.; Moraes, Valeria Conde Alves [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil)], e-mail: beth@cbpf.br, e-mail: conde@cbpf.br; Moreira, Ana Paula D. [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Inst. de Quimica. Dept. de Quimica Analitica], e-mail: duarteap@gmail.com

    2008-10-15

    The crystal structure of the synthetic hydroxyapatite with 12.8 ({+-} 0,64) wt. % CO{sub 3}{sup 2-} ion content was analyzed by X-ray diffraction using the Rietveld refinement method employing Pearson VII and pseudo-Voigt functions to fit the X-ray profile. The results obtained for unit cell parameters when compared to pattern hydroxyapatite showed a decrease in the a (=b) parameter and an increase in the c parameter without significant difference between the functions employed. The separation of the anisotropic broadening of reflections originated from unit cell strains indicated that this effect is dominant in reflection line broadening, principally to hkl plans with an interatomic distance lower than 2,24 angstrom. Modifications in the atomic coordinates of C atom were noted mainly in PO{sub 4}{sup 3-} (B site) and OH{sup -} (A site) sites. The average crystallite size in the crystallography axis directions (002 and 300) suggests equi axial morphology. The results obtained to CO{sub 3}{sup 2}- content were 11.72 ({+-} 0,64) wt. % to Pearson VII and 13.20 ({+-} 0,64) wt. % to pseudo-Voigt function. The refinement of the occupancy factors to C atoms in both sites PO{sub 4}{sup 3-}(B) and OH{sup -} (A) indicated higher insertion in phosphate site than hydroxide site. However, the relative occupancy of the C atom observed in the B site is lower than in the A site. (author)

  16. Application of the Rietveld method in structural analysis of catalysts based on CuO/CeO{sub 2}; Aplicacao do metodo de Rietveld na analise estrutural de catalisadores a base de CuO/CeO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Neiva, L.S.; Ribeiro, M.A.; Bispo, A.; Simoes, A.N.; Gama, L., E-mail: lsoutoneiva@yahoo.com.br [Universidade Federal de Campina Grande (UFCG), PB (Brazil). Departamento de Engenharia de Materiais

    2011-07-01

    This work has as aim to synthesize catalysts composed by CuO/CeO{sub 2} by means two distinct methods of synthesis, they are: combustion synthesis and Pechini. The catalysts composed by CuO/CeO{sub 2} were synthesized with CuO in condition of dopant element. The value of the CuO concentration ranged between 0 and 0.5 mol. Has been done a structural analysis related to how the kind of synthesis method used influences over physical characteristic of the catalytic material. The obtained catalysts were characterized by X-ray diffraction with refinement by Rietveld method. According to results, the synthesized catalysts showed crystalline structures formed mostly by CeO{sub 2} phase, as expected, since this is the host matrix for the dopant element. The catalysts obtained by the Pechini method presented structures with a smaller amount of segregated phases formed by CuO, according to the results of the structural analysis. (author)

  17. Petroleum reservoir fault reactivation problem analysis through finite element viscodamage model; Analise de problema de reativacao de falha em reservatorio de petroleo por modelo de viscodano via metodo dos elementos finitos

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, Julliana de P.V.; Guimaraes, Leonardo J. do N.; Gomes, Igor F.; Pontes Filho, Ivaldo Dario da S. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil)

    2008-07-01

    Recently, many new constitutive models for geomechanical materials were developed taking into account its complex behavior. The continuum damage mechanics, formulated according to irreversible thermodynamics principles, can be used to model materials subjected to degradation of its mechanical properties. Reservoir depletion may result in compaction and subsidence that induces fault reactivation, among others consequences. The fault reactivation problem in petroleum reservoirs has been widely studied as its changes completely the flow regime in subsurface. Isotropic damage model can be used to model the fault reactivation process, where its hydro-mechanical properties (stiffness and permeability) are affected during the reservoir production. In this paper, a fault reactivation case in a synthetic reservoir is presented and a sensibility analysis is carried out to identify the main variables that influence this process. (author)

  18. Steam and solvent injection as an advanced recovering method for heavy oil reservoirs; Injecao de vapor e solvente como um metodo de recuperacao avancada em reservatorios de oleo pesado

    Energy Technology Data Exchange (ETDEWEB)

    Galvao, Edney Rafael V.P.; Rodrigues, Marcos Allyson F.; Barbosa, Janaina Medeiros D.; Barillas, Jennys Lourdes M.; Dutra Junior, Tarcilio V.; Mata, Wilson da [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil)

    2008-07-01

    Currently a resource more and more used by the petroleum industry to increase the efficiency of steam flood mechanism is the addition of solvents. The process can be understood as a combination of a thermal method (steam injection) with a miscible method (solvent injection), promoting, thus, the reduction of interfacial tensions and oil viscosity. The mobility of the displaced fluid is then improved, resulting in an increase of oil recovery. To better understand this improved oil recovery method, a numerical study of the process was driven contemplating the effects of some operational parameters (distance between wells, injection fluids rate, kind of solvent and injected solvent volume) on the accumulated production of oil and recovery factor. Semisynthetic models were used in this study but reservoir data can be extrapolated for practical applications situations on Potiguar Basin. Simulations were performed in STARS (CMG, 2007.11). It was found that injected solvent volumes increased oil recovery and oil rates. Further the majority of the injected solvent was produced and can be recycled. (author)

  19. The two means method for the attenuation coefficient determination of archaeological ceramics from the North of Parana; Metodo dos dois meios para a determinacao do coeficiente de atenuacao de ceramicas arqueologicas do norte do Parana

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Richard Maximiliano Cunha e

    1997-12-31

    This work reports an alternative methodology for the linear attenuation coefficient determination ({mu} {rho}) of irregular form samples, in such a way that is not necessary to consider the sample thickness. With this methodology, indigenous archaeological ceramics fragments from the region of Londrina, north of Parana, were studied. These ceramics fragments belong to the Kaingaing and Tupiguarani traditions. The equation for the {mu} {rho} determination employing the two mean method was obtained and it was used for {mu} {rho} determination by the gamma ray beam attenuation if immersed ceramics, by turns, in two different means with known linear attenuation coefficient. By the other side, {mu} theoretical value was determined with the XCOM computer code. This code uses as input the ceramics chemistry composition and provides an energy versus mass attenuation coefficient table. In order to validate the two mean method validation, five ceramics samples of thickness 1.15 cm and 1.87 cm were prepared with homogeneous clay. Using these ceramics, {mu} {rho} was determined using the attenuation method, and the two mean method. The result obtained for {mu} {rho} and its respective deviation were compared for these samples, for the two methods. With the obtained results, it was concluded that the two means method is good for the linear attenuation coefficient determination of materials of irregular shape, what is suitable, specially, for archaeometric studies. (author) 25 refs., 29 figs., 28 tabs.

  20. Influence of reason citric acid/ metal cations in the synthesis of mullite by Pechini Method; Iinfluencia da razao acido citrico/cations metalicos na sintese de mulita pelo Metodo Pechini

    Energy Technology Data Exchange (ETDEWEB)

    Braga, A.N.S.; Costa, D.L.; Farias, R.M.C.; Neves, G.A.; Lira, H.L.; Menezes, R.R., E-mail: Alluskynha@homail.com [Universidade Federal de Campina Grande (UFCG), PB (Brazil). Departamento de Engenharia de Materiais

    2014-07-01

    Mullite is a ceramic material with high technological applications. Its synthesis has been extensively studied due to their excellent properties. Thus, this paper proposes to obtain mullite by Pechini method. The amount of acid citric/metal cations in proportions of 3:1 and 1:1 were investigated in order to understand their influence in obtaining the mullite phase. The synthesized samples were characterized by X-ray diffraction (XRD) and thermal analysis (TG/DTG and DTA). The results showed that the ratio citric acid/metal cations influence on the formed phase with the mullite obtained only in proportion 1:1. With the increase of the ratio to 3:1 was observed the formation of the alumina layer. (author)

  1. Hurdle technology to preserve the 'Golden' papaya post harvest quality;Metodos combinados para preservar a qualidade pos-colheita do mamao 'Golden' tipo exportacao

    Energy Technology Data Exchange (ETDEWEB)

    Molinari, Andrea Cristina Fialho, E-mail: molinari_af@yahoo.co

    2007-07-01

    With the purpose of evaluating a combination of post harvest techniques on papaya Golden storage, the following treatments were investigated: carton boxes packaging (CP); CP + plastic bag of PEBD - low density polyethylene film, with 0.05mm of thickness (PE); CP + PEBD with 0.025mm of thickness impregnated with mineral ethylene scavenger (PEAbs); gamma-irradiation (0.4 kGy and 0.7 kGy); and refrigerated storage at 10 deg C e 90% of relative humidity for 2, 5, 10, 15, 20, 25, 30 and 35 days plus five days under environmental conditions to allow ripening and to simulate the product marketing. To evaluate the effects on fruit quality the following measurements were taken: - first experiment, disease incidence, skin color and loss of turgidity (as visual variables); skin and flesh color, weight loss, flesh firmness, total soluble solids, total titratable acidity, pH, lycopene and beta-carotene composition; - second experiment, sensorial analysis on samples submitted to the treatments with better results from the first experiment. Post harvest diseases were the main factor responsible for discarding fruits. Percentage of weight loss was higher on papayas stored without plastic packaging. Time affected the flesh firmness (F = 95%). However, there wasn't influence of the treatments on that parameter. A significant effect on skin color was observed with interaction between irradiation (0.4 and 0.7 kGy) and storage period. Once reached the edible stage, irradiated papayas presented more uniformity on skin color. For beta-carotene and Lycopene, the mean values were 1.27 to 1.79 and 19.16 to 23.90 mug/ml of flesh, respectively. But those substances weren't affected by the combined methods or the time. The same behavior were observed for total soluble solids, total titratable acidity and pH (mean values of 11.53 to 12.20 deg Brix, 0.117 to 0.136 g of citric acid/100g of flesh and 4.91 to 5.04, respectively). On sensory evaluation, the judges didn't get to detect significant differences among papayas submitted to different treatments. A synergism was verified on the techniques combination, with the best results obtained from the association of CP + PEabs + gamma-irradiation at 0.4 kGy, which reached a total storage period of 35 days. Thus, that is the post harvest hurdle technology recommend for exporting 'Golden' papayas to markets with quarantine restrictions to fruit-flies (author)

  2. Practical methods for the functioning evaluation of the whole body counter system Accuscan II of the ININ; Metodos practicos para la evaluacion del comportamiento del sistema contador de cuerpo entero Accuscan II del ININ

    Energy Technology Data Exchange (ETDEWEB)

    Alfaro L, M. M.; Ramirez J, F. J.; Mondragon C, L., E-mail: mercedes.alfaro@inin.gob.mx [ININ, Carretera Mexico-Touca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2013-10-15

    The whole body counter system Accuscan II of the Instituto Nacional de Investigaciones Nucleares (ININ), was designed and built to quantify and to measure radionuclides fission product as well as gamma emitters, with a maximum sensibility of less than 10 n Ci for cobalt 60 at one time of counting of 5 minutes. The system has two detectors of Ge(Hp) with Beryllium window to a relative efficiency of 25% in a counting configuration of vertical scanning, this configuration gives a plane response of constant efficiency. In this work some practical methods developed in the Internal Dosimetry Laboratory to carry out the functioning evaluation of the whole body counter system Accuscan II of the ININ are described. With the obtained results of this evaluation we can decide fine adjustments will be necessary for the optimization of the equipment operation. The evaluation of this equipment was especially necessary, due to its 21 years-old antiquity and for the gradual changes that has in its functioning. The equipment is intrinsically a gamma spectrometry system and some described experiences could be applied too in other gamma spectrometry systems. (Author)

  3. Optimization of the synthesis of a high specific activity 125{sup I}-labelled hapten for radioimmunoassays; Optimizacion de un metodo de preparacion de un radiohapteno-125''I para ria de alta actividad especifica

    Energy Technology Data Exchange (ETDEWEB)

    Suraez, C; Paz, D; Simon, M A; Romero del Hombrebueno, B

    1994-07-01

    In this first report it is described the synthesis, separation and purification of the 2-radioiodinated histamine- I-labelled histamine by a mixed anhydride reaction. About 75% incorporation of I{sup -}125, from Na{sup 1}25I, was achieved with a molecular ratio of 1:1 mixed anhydride:histamine. The radiochemical purity of the conjugate by TLC was > 99% and its theoretical specific activity, 3850 {mu}Ci/{mu}g. Dissolved in ethanol and held at -20 degree centigree under darkness decomposition on storage didn't exceed 1% per month. (Author) 13 refs.

  4. Method for evaluation of doses from ingestion of polonium, bismuth and lead as natural radioactive material(NORM); Metodo de evaluacion de dosis por ingestion de polonio, bismuto y plomo como materiales radiactivos naturales

    Energy Technology Data Exchange (ETDEWEB)

    Pena, Vanessa; Puerta, Anselmo; Morales, Javier, E-mail: vpenam@ullal.edu.co, E-mail: japuerta@unal.edu.co, E-mail: jmorales@unal.cdu.co [Universidad Nacional de Colombia, Medellin (Colombia). Grupo de Fisica Radiologica

    2013-07-01

    In this work was carried out an evaluation of dose from ingestion of radioactive daughters of radon (lead, bismuth and polonium), taking into account ages from three months up to adult men, using the new model of the human alimentary tract HATM and methodology of calculating doses proposed by the ICRP publication 103, which allows the estimation of dose based on the concentration of the radionuclide present in the diet or in the water of consumption.

  5. A comparative analysis of the EEDF obtained by Regularization and by Least square fit methods; Un analisis comparativo de la EEDF obtenido por metodos de regularizacion y por un ajuste de minimos cuadrados

    Energy Technology Data Exchange (ETDEWEB)

    Gutierrez T, C.; Flores Ll, H. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2004-07-01

    The second derived of the characteristic curve current-voltage (I - V) of a Langmuir probe (I - V) is numerically calculated using the Tikhonov method for to determine the distribution function of the electrons energy (EEDF). One comparison of the obtained EEDF and a fit by least square are discussed (LS). The I - V experimental curve is obtained in a plasma source in the electron cyclotron resonance (ECR) using a cylindrical probe. The parameters of plasma are determined of the EEDF by means of the Laframboise theory. For the case of the LS fit, the obtained results are similar to those obtained by the Tikhonov method, but in the first case the procedure is slow to achieve the best fit. (Author)

  6. Determination of viscosity of fayalite slags for kv model and measurements by means of inclined plane; Estimacion de la viscosidad de escorias fayaliticas utilizando el modelo de calculo kv y el metodo experimental del plano inclinado

    Energy Technology Data Exchange (ETDEWEB)

    Bazan, V.; Goni, C.; Castella, L.; Brandaleze, E.; Verdeja, L. F.; Parra, R.

    2006-07-01

    The viscosity of the lands represents one of the most relevant variables of most of the processes metallurgical and kinetics of the refine operations, since it is one of the decisive factors of the efficiency in the reactions between metal and lag, as much as slag-refractory. In the last decades, the mathematical models of different metallurgical processes have established methods to predict viscosity of mixtures of oxides fused to high temperatures in function of the chemical composition. The model developed by Toguri, based on the data reported by Johasen and Winterhager et al has proposed the Kv model. The used index it is similar to the relationship used in the steel industry like the basicity index. It is presented in this work values determined of viscosity in experimental form by means of the technique of inclined plane. (Author)

  7. Modelos de desarrollo de software de exportacion en el contexto de una region emergente: Caso area metropolitana de Monterrey, analisis de campo por el metodo de regresion lineal multiple.

    Directory of Open Access Journals (Sweden)

    Torres, F.

    2009-01-01

    Full Text Available The objective of this document is to give to know the advantages that the different successful development models have offered for companies development of export software, making a synthesis from the CMM, until arriving to the CMMI, without stopping to make a critical analysis on the two models that have identified the critical factors for the export of software of the called countries of "3I" that they have demonstrated its success in this segment like: the model of factors of success for the software export (Heeks and Nicholson, 2002 and the model Oval (Carmel, E., 2003b, giving the minimum recommendations to the Mexican companies, developments of software export, have the competitiveness required in the international environment. This work is the result of the bibliographical revision of the models of software development and it is part of the doctoral thesis, about a sample of 40 companies developments of software export and the critical factors: Standard technological, Capacity of technological innovation, Formation of human capital, financial Capital and Support in investigation and development, with the purpose of identifying the opportunity areas to improve their international competitiveness, besides the economic results that can be obtained. The present study is based on the application of the statistical technique of the model of multiple lineal regressions, giving the following values: R= 0.549, 2 R =0.302, 2 R Ajus = 0.275. The positioning of the companies Mexican developments of software export and, in the particular case in the Metropolitan Area of the City of Monterrey, in the world market of software and related services, it will depend: that the company has a model to develop software export; of the consolidation of managerial associations of TI for the development of the export software and of the development of managerial consortia of export software in the Metropolitan Area of the City of Monterrey that they come to consolidate this industry in the northeast of the country.

  8. Dating of the archaeological site 'El Tigre' by the thermoluminescent method; Fechamiento del sitio arqueologico 'El Tigre' por el metodo de termoluminiscencia

    Energy Technology Data Exchange (ETDEWEB)

    Portilla, R. De la [ENAH, Periferico Sur y Zapote, 14030 Mexico D.F. (Mexico); Gonzalez, P.R.; Mendoza, D. [ININ, 52750 La Marquesa, Ocoyoacac, Estado de Mexico (Mexico); Vargas, E. [Instituto de Investigaciones Antropologicas, UNAM, 04510 Mexico D.F. (Mexico); Ramirez, A. [Instituto de Geofisica, UNAM, 04510 Mexico D.F. (Mexico)

    2007-07-01

    Full text: The dating of pre hispanic pottery, is supported by techniques such as stratigraphy, typology, in physical and chemical procedures, as the analysis of {sup 14}C and the thermoluminescence (TL). The last one permits us obtain absolute dating of archaeological pottery with an acceptable precision. In this work we apply the applied the thermoluminescent technique to verify the age of the Pre-Classic and Classic Terminal periods proposed for the archaeological site 'El Tigre', Campeche. The samples were obtained during a work period and the radiation of the ground of background (emitted by the ground), as well as the contribution of the cosmic radiation was measured with thermoluminescent dosemeters of LiF: Mg,Cu,P + PTFE, put in the sample zone. The preliminary results indicate that not all the analyzed samples can be dated. The viability of the dating of the samples is discussed based on the fact and function of the presence of certain crystalline phases such as calcite and quartz. The discussion is complemented emphsizing the importance of handling the conditions of handling of samples. (Author)

  9. Validation of the implementation of IMRT with three dosimetric methods of independent verification; Validacion de la puesta en marcha de la IMRT con tres metodos dosimetricos de verificacion independientes

    Energy Technology Data Exchange (ETDEWEB)

    Tortosa Oliver, R. A.; Chinillach ferrando, N.; Alonso Arrizabalaga, S.; Campayo Esteban, J. M.; Morales Marco, J. C.; Soler Catalan, P.; Andreu Martinez, F. J.

    2013-07-01

    The TG119 is a simple and clear framework to verify the implementation of IMRT technique in a radiotherapy service. Verifications of this document recommended tests conducted with the three dosimetric methods listed above, allow to affirm that our Center is within the margins of tolerance considered suitable in the TG119 for the clinical implementation of IMRT. (Author)

  10. CUSTOS DE PRODUÇÃO DE GADO BOVINO EM REGIME DE CONFINAMENTO: ANALISE DO METODO DE CUSTEIO POR ABSORÇÃO EM UMA PROPRIEDADE RURAL EM TANGARA DA SERRA-MT

    Directory of Open Access Journals (Sweden)

    Monica Aparecida Burgos Alexandre Pinto

    2014-06-01

    Full Text Available A pecuária de corte é uma importante atividade econômica desenvolvida no Brasil, informações do Ministério da Agricultura dão conta de que a carne bovina, dentre outras carnes produzidas neste país, deverá ter um aumento na produção em 12,6 milhões de toneladas até 2019, isso se deve ao adequado uso das pastagens por meio de técnicas agronômicas modernas e de investimentos em genética, acarretando uma menor utilização de áreas. Este trabalho foi confeccionado com o objetivo de analisar os custos de produção na terminação do gado de corte em regime de confinamento, através do emprego do método de custeio. A metodologia utilizada para a presente pesquisa envolveu estudo de caso de uma propriedade rural, localizada no município de Tangará da Serra-MT. Através de informações coletadas na fazenda, levantou-se o custo do confinamento, bem como a identificação dos elementos que possuem maior influência em relação ao custo de produção na atividade. Foram considerados dois quantitativos de animais confinados, sendo 12.000 animais, durante o ciclo de manejo de 2011 e 11.000 animais, durante o ciclo de manejo de 2012. No resultado da pesquisa verificou-se que os componentes do custo operacional efetivo exerceram maior influência sobre os custos da atividade de confinamento de gado, destacando-se em ordem decrescente: a aquisição de animais, a alimentação. Em relação a essa atividade mostrou-se rentável, tendo como vantagem de destaque o reduzido custo da aquisição boi magro, pois veio de uma filial do grupo, e outro fator foi a alta no preço do período que foi realizado a venda. Conclui-se que a atividade tem condições de se manter em longo prazo se continuar com planejamento adequado.

  11. Analysis of a calculation method for the determination of the value of safety or control bars; Analisis de un metodo de calculo para la determinacion del valor de barras de seguridad o control

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar H, F; Torres A, C; Filio L, C [ININ, Gcia. de Reactores, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    1982-09-15

    Due to the control or safety bars in a nuclear reactor are constituted by strongly absorbent materials, the Diffusion Theory like tool for the calculation of bar values is not directly applicable, should it use the Transport Theory. However the speed and economy of the Diffusion codes for the reactors calculation, those make attractiveness and by this reason its are used in the determination of characteristic parameters and even in the determination of bar values, not without before to make some theoretical developments that allow to make applicable this theory. The application of the Diffusion Theory in strongly absorbent media is based on the use of some effective cross sections distinct from the real ones obtained when imposing the reason that among the flow and it gradient in the external surface of such media (control element in general, bar type or flagstone) be similar to the one obtained using Transport Theory in all the control region (multiplicative and absorbent media) with those real cross sections. The effective cross sections were obtained of the Leopard-NUMICE cell code which has incorporate the respective calculation theory of effective cross sections. Later these constants its were used in the bidimensional diffusion code Exterminator-II, simulating in it, the distribution of safety or control bars. From the cell code its were also obtained the respective constants of the homogeneous fuel cell. The results as soon as those obtained bar values of the diffusion code, its were compared with some experimental results obtained in the R{phi} Swedish reactor of natural uranium and heavy water. In this work an analysis of the bar value of one of them, trying to determine the applicability of the method is made. (Author)

  12. A method for estimation of hydrological sensibility applied in Golfo San Jorge basin. Province of Chubut. Argentina; Un metodo para estimar la sensibilidad hidrologica aplicado en la cuenca del Golfo San Jorge. Provincia de Chubut. Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez, M. A.; Scatizza, C.; Rojo, M.; Preiato, S. A.; Hernandez, L.

    2009-07-01

    A method developed and used in an area of Chubut Province is described. The object of the method is to determine the underground and surficial hydrological sensitivity in order to select the site of petroleum facilities with the least possible environmental hydric risk. It is based on the conjunction of the GOD method used to assess the intrinsic aquifer vulnerability (original version) and the proposed La Plata Method (MLP) for the surficial hydrological sensitivity. The latter method assigns numerical values based on landforms (positive and negative), slope percent and seasonality of the water regime, using a complexive range scale from zero to one. The Surficial Sensitivity factor results from the average of the three indicators and includes five categories, from low to extreme values. For a global coverage in the underground and surficial terrestrial arches (geo environmental map) it is proposed to compare the GOD values with those of the MLP method using a GIS, through the mathematical overlapping of two raster layers (map algebra) in each map pixel. In addition to the cartographic display, attribute tables can be used to estimate the environmental pollution in soils and waters, existing infrastructure and location of new facilities and drillings. The Arc Map 9.1 program was used due to its capacity for a permanent and quasi-automatic updating of thematic mapping. The map corresponding to Cerro for the initial position 2007 is presented as an example. (Author) 6 refs.

  13. Microscopic model for the non-linear fluctuating hydrodynamic of {sup 4} He superfluid helium deduced by maximum entropy method; Modelo microscopico para la hidrodinamica fluctuante no lineal del {sup 4}He superfluido deducido mediante el metodo de maxima entropia

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez R, J.T

    1998-10-01

    This thesis presents a microscopic model for the non-linear fluctuating hydrodynamic of superfluid helium ({sup 4} He), model developed by means of the Maximum Entropy Method (Maxent). In the chapter 1, it is demonstrated the necessity to developing a microscopic model for the fluctuating hydrodynamic of the superfluid helium, starting from to show a brief overview of the theories and experiments developed in order to explain the behavior of the superfluid helium. On the other hand, it is presented the Morozov heuristic method for the construction of the non-linear hydrodynamic fluctuating of simple fluid. Method that will be generalized for the construction of the non-linear fluctuating hydrodynamic of the superfluid helium. Besides, it is presented a brief summary of the content of the thesis. In the chapter 2, it is reproduced the construction of a Generalized Fokker-Planck equation, (GFP), for a distribution function associated with the coarse grained variables. Function defined with aid of a nonequilibrium statistical operator {rho}hut{sub FP} that is evaluated as Wigneris function through {rho}{sub CG} obtained by Maxent. Later this equation of GFP is reduced to a non-linear local FP equation from considering a slow and Markov process in the coarse grained variables. In this equation appears a matrix D{sub mn} defined with a nonequilibrium coarse grained statistical operator {rho}hut{sub CG}, matrix elements are used in the construction of the non-linear fluctuating hydrodynamics equations of the superfluid helium. In the chapter 3, the Lagrange multipliers are evaluated for to determine {rho}hut{sub CG} by means of the local equilibrium statistical operator {rho}hut{sub l}-tilde with the hypothesis that the system presents small fluctuations. Also are determined the currents associated with the coarse grained variables and furthermore are evaluated the matrix elements D{sub mn} but with aid of a quasi equilibrium statistical operator {rho}hut{sub qe} instead of the local equilibrium operator {rho}hut{sub l}-tilde. Matrix elements that lead to the local transport coefficients for the superfluid helium, by means of a generalization of the Green-Kubo fluctuation-dissipation relation, in analogy with the results present in the Appendix A, obtained with a local equilibrium statistical operator {rho}hut{sub l}-tilde. Specified the Lagrange multipliers, the currents and the local transport coefficients, a non-linear local FP equation is determined for the superfluid helium in the Fourier space. Starting with such FP equation their associated non-linear equations of the Langevin type are built, where the random forces that appear are of multiplicative type. Forces that are expressed as the product of Gaussian random variables and local variablesin such way that the variances of the random variables are independent of the local variables. Finally, applying the Fourier inverse transformed to the non-linear equations of the Langevin type in the space of Fourier, the equations of the non-linear fluctuating hydrodynamic are built for the superfluid helium in the configuration space. Lastly, in the chapter 4, it is presented a discussion of the results and the conclusions of this thesis. (Author)

  14. Characterization of tissues equivalent to the human body by the Monte Carlo method for X-rays; Caracterizacion de tejidos equivalentes al cuerpo humano mediante el metodo Monte Carlo para rayos X

    Energy Technology Data Exchange (ETDEWEB)

    Vega R, J.; Huamani T, Y.; Mullisaca P, A. F.; Yauri C, L., E-mail: josevegaramirez@yahoo.es [Universidad Nacional de San Agustin de Arequipa, Av. Independencia s/n, 04000 Arequipa (Peru)

    2017-10-15

    There is a need to have materials equivalent to the human body that have the appropriate characteristics to be used as a substitute tissue in the clinical practices of radio-diagnosis, radiotherapy. In Arequipa, Peru, there are two health centers in radiotherapy applications, one with a Theratron Co-60 gamma irradiator and another with Elekta Linac; the Medical Physics Area of the School of Physics of the National University of San Agustin de Arequipa, were four equivalent materials based on epoxy resin, phenolitic spheres, calcium carbonate, etc. were built, such as bone tissue, soft tissue, adipose and lung tissue compared with water, whit the purpose of studying and applying them in future clinical applications. In this work we describe its physical and dosimetric characterization to determine its use as an equivalent material or manikin. The materials are 1 cm thick and 30 cm in diameter, the materials are non-malleable solids, they do not degrade, they have stability in their consistency due to temperature and irradiation, they are not toxic in their use, determining densities from 0.32 g/cm{sup 3} for the lung tissue to 1.8 g/cm{sup 3} for the bone material. These materials were analyzed by scanning electron microscopy, giving the percentages by weight of the elements found to determine their effective atomic number, the physical analysis to determine their mass absorption and energy coefficients, which were studied for energy photons between 1 KeV at 20 MeV. The simulation of the equivalent materials and the physical and dosimetric study were found using the code Penelope 2008 Monte Carlo method and validated by the Nist database. The results obtained according to their coefficients of mass attenuation of each material, show lung, bone, soft and adipose tissue with differences with respect to the same Nist materials. The range maximum and minimum Rd deviation found was 35.65 - 3.16 for bone, 28.5 - 6.74 for lung, 33.78 - 9.06 for soft tissue and 86.42 - 1.28 for adipose tissue. The Pdp dosimetric analysis was performed with gamma radiation (Co-60) and high energy X-rays (6 MV). (Author)

  15. Study of the presence of free radicals formed in tumors, using the electronic paramagnetic resonance spectroscopy method; Estudiar la presencia de radicales libres formados en tumores, usando el metodo de espectroscopia de resonancia paramagnetica electronica (RPE)

    Energy Technology Data Exchange (ETDEWEB)

    Chonchon, Y [Instituto Venezolano de Investigaciones Cientificas (IVIC). Centro de Estudios Avanzados (CEA). Postgrado en Fisica Medica, Altos de Pipe (Venezuela); Silva, P [Instituto Venezolano de Investigaciones Cientificas (IVIC). Centro de Fisica. Laboratorio de la Materia Condensada, Altos de Pipe (Venezuela); Gutt, F [Instituto Venezolano de Investigaciones Cientificas (IVIC). Centro Tecnologico. Unidad de Tecnologia Nuclear. Laboratorio Secundario de Calibracion Dosimetrica, Altos de Pipe (Venezuela); Almeida, C de [Universidade do Estado do Rio de Janeiro (UERJ). Laboratorio de Ciencias Radiologicas (LCR), Rio de Janeiro (Brazil)

    2001-07-01

    It studies molecules and ions in order to provide a structural and dynamic system information, establishing comparisons among different stadiums of the same tumor and/or different tumors, as well as the relationship among the behaviors of healthy tissues and carcinogenic tissues. [Spanish] Estudia moleculas e iones con electrones desapareados a fin de proporcionar una informacion estructural y dinamica del sistema, estableciendo comparaciones entre los distintos estadios de un mismo tumos y/o diferentes tumores, asi como la relacion entre los comportamientos de tejidos sanos y tejido cancerigeno.

  16. Supersonic flow with shock waves. Monte-Carlo calculations for low density plasma. I; Flujo supersonico de un plasma con ondas de choque, un metodo de montecarlo para plasmas de baja densidad, I.

    Energy Technology Data Exchange (ETDEWEB)

    Almenara, E; Hidalgo, M; Saviron, J M

    1980-07-01

    This Report gives preliminary information about a Monte Carlo procedure to simulate supersonic flow past a body of a low density plasma in the transition regime. A computer program has been written for a UNIVAC 1108 machine to account for a plasma composed by neutral molecules and positive and negative ions. Different and rather general body geometries can be analyzed. Special attention is played to tho detached shock waves growth In front of the body. (Author) 30 refs.

  17. Analytical method of Kr-85 determination, using cryogenic concentration and separation and liquid scintillation counting; Desarrollo del metodo de concentracion y se paracion criogenica cromatografica y medida radiactiva por centelleo liquido de Kr-85

    Energy Technology Data Exchange (ETDEWEB)

    Heras, M C; Perez, M M; Grau, A

    1983-07-01

    The method used in the Laboratory of the JEN for the determination of Kr-85 levels in gaseous effluents of nuclear power and in the atmosphere is described. Samples of air, collected in metallic cylinders, are introduced into a gas-solid chromatographic separation system which resolves Kr from the other air components. The separated Kr ia dissolved in a toluene based scintillation cocktail, and the Kr-85 content is determined by liquid scintillation counting. (Author)

  18. The radioactive equilibrium and determination methods for ratio e Ra/U; Desequilibrio Radiactivos-1. Metodo {sub {beta}}-{gamma}. Determinacion de la razon eRa/U. Valoracion del contenido en U{sub 3}O{sub 8}

    Energy Technology Data Exchange (ETDEWEB)

    Mingarro, E

    1966-07-01

    The main problems concerning the radioactive non-equilibrium on minerals and a simultaneous counting procedure for {beta}- and {gamma}- activities developed to solve those problems, are described. (Author)

  19. Spectra and depth-dose deposition in a polymethylmethacrylate breast phantom obtained by experimental and Monte Carlo method; Espectros e deposicao de dose em profundidade em phantom de mama de polimetilmetacrilato: obtencao experimental e por metodo de Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    David, Mariano G.; Pires, Evandro J.; Magalhaes, Luis A.; Almeida, Carlos E. de; Alves, Carlos F.E., E-mail: marianogd08@gmail.com [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Lab. Ciencias Radiologicas; Albuquerque, Marcos A. [Coordenacao dos Programas de Pos-Graduacao de Engenharia (COPPE/UFRJ), RJ (Brazil). Instituto Alberto Luiz Coimbra; Bernal, Mario A. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Instituto de Fisica Gleb Wataghin; Peixoto, Jose G. [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2012-08-15

    This paper focuses on the obtainment, using experimental and Monte Carlo-simulated (MMC) methods, of the photon spectra at various depths and depth-dose deposition curves for x-rays beams used in mammography, obtained on a polymethylmethacrylate (PMMA) breast phantom. Spectra were obtained for 28 and 30 kV quality-beams and the corresponding average energy values (Emed) were calculated. For the experimental acquisition was used a Si-PIN photodiode spectrometer and for the MMC simulations the PENELOPE code was employed. The simulated and the experimental spectra show a very good agreement, which was corroborated by the low differences found between the Emed values. An increase in the Emed values and a strong attenuation of the beam through the depth of the PMMA phantom was also observed. (author)

  20. A method for detection of mechanical collisions and couch-beam intersections; Un metodo para la prediccion de colisiones mecanicas y de intersecciones del haz con la mesa de tratamiento

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez Galiano, P.; Crelgo Alonso, D.; Gonzalez Sancho, J. M.; Vivanco Parellada, J.; Fernandez Garcia, J.; Barbes Fernandez, B.; Pamos Urena, M.; Monserrat Fuertes, T.

    2009-07-01

    Two software applications for avoiding mechanical collisions and beam blocking by the couch are described. The method used is based on a simplified model of the couch cross-sections and a very simple routine. The algorithms employed and the graphical interfaces developed are described, along with several software implementation tests. The accuracy of predictions was within 5 mm, therefore the results are satisfactory despite the simple approach assumed. (Author) 11 refs.

  1. Estudio comparativo de los metodos analitico-sintetico y global en el aprendizaje de la lectura (Comparative Study of the Analytical-Synthetical (Phonics) and Global (Sight) Reading Methods).

    Science.gov (United States)

    Carbonell de Grompone, Maria A.; And Others

    An investigation into the phonics and sight methods of reading instruction being taught in Uruguay schools seeks valid predictions in support of each approach. The study, written in Spanish, examines the progressive reading habits and abilities of 12 first-grade classes. Teachers assigned to teach each method uniformly had equivalent training and…

  2. Study of ceramics from circular archaeological sites of Amazonic Basin by geochemical methods: dating and characterization; Estudo de ceramicas de sitios arqueologicos circulares da Bacia Amazonica por meio de metodos geoquimicos: datacao e caracterizacao

    Energy Technology Data Exchange (ETDEWEB)

    Nicoli, Ieda Gomes

    2000-09-01

    The aim of this work is to examine by means of characterization and dating pottery recently discovery inside archaeological sites recognized with circular earth structure in Acre State - Brazil which may contribute to the research in the reconstruction of part of the pre-history of the Amazonic Basin. These sites are located mainly in the Hydrographic Basin of High Purus River. Three of them were strategic chosen which provide the ceramics: Lobao, in Sena Madureira County at north; Alto Alegre, in Rio Branco County at east and Xipamanu I, in Xapuri County at south. The X-ray diffraction mineral analysis made possible to identify two types of crystal structures of ceramic minerals: quartz and M-Kaolinite. Neutron activation analysis in conjunction with multivariate statistical methods were applied for the ceramic characterization and classification. An homogeneous group was established by all sherds collected from Alto Alegre and was distinct from all the other two groups analyzed. Some of the sherds collected from Xipamanu I appeared in Lobao's urns, probably because they had the same fabrication process. The Lobao's urns presented a homogeneous group. Geochronology of these materials was carried out by Thermoluminescence. The Xipamanu I was the oldest site and Lobao the youngest. The average age of Xipamanu I and Alto Alegre were 2600 and 2070 years respectively. The average age of of occupation was 400 years to Alto Alegre and 970 years to Xipamanu I. The most probably date for Lobao was 1880 years. (author)

  3. Synthesis of the lithium metatitanate, Li{sub 2}TiO{sub 3}, by the modified combustion method; Sintesis del metatitanato de litio, Li{sub 2}TiO{sub 3}, por el metodo modificado de combustion

    Energy Technology Data Exchange (ETDEWEB)

    Cruz, D.; Bulbulian, S. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Pfeiffer, H. [IIM-UNAM, A.P. 70-360, 04510 Mexico D.F. (Mexico)]. e-mail: sb@nuclear.inin.mx

    2005-07-01

    A modified combustion method to obtain Li{sub 2}TiO{sub 3} it was used, a compound to be used in fusion reactors like tritium generator material. To obtain Li{sub 2}TiO{sub 3} were proven different molar ratios of lithium hydroxide (LiOH), titanium oxide (TiO{sub 2}) and urea (CO(NH{sub 2}){sub 2}), as well as different heating temperatures (550, 650 and 750 C). The characterization of the products it was carried out using X-ray diffraction, Scanning electron microscopy and Thermal gravimetric analysis. The sample prepared with a molar ratio Li: Ti: urea = 2.75: 1: 3 was the one that presented as only product the Li{sub 2}TiO{sub 3}. The particle size and the morphology found in the Li{sub 2}TiO{sub 3}, showed similar particle size and morphology to the TiO{sub 2} used as precursor. (Author)

  4. Response Analysis of eight native species of high Andean forest with two methods of propagation; Analisis de la respuesta de ocho especies nativas del bosque alto andino ante dos metodos de propagacion

    Energy Technology Data Exchange (ETDEWEB)

    Liliana, Castaneda Sandra; Ernesto, Garzon Alvaro; Angel, Cantillo Miguel; Patricia, Torres Monica; Jairo, Silva Luis

    2007-07-01

    The objective of this research was to generate information on the native tree species represent an alternative in the ecological restoration of the Colombian high Andean forests, according to its dynamo-genetic characteristics. We have chosen and spread the species: Baccharis latifolia (R and P), Bocconia frutescens L., Cordia cylindrostachya (R and P), Diplostephium rosmarinifolium (Benth), Drymis granadensis L f., Eupatorium angustifolium (Kunth), Palicourea vaginata Benth, and Palicourea linearifolia Wernham. The species include a morphological description of flowers, fruits and seeds, and ISTA tests. The spread experiments were made in the nurseries of the Universidad Distrital and La Florida park. For the sexual spread, we have used as treatments four gibberellins concentrations and three shadow conditions, while the vegetative spread consisted of two diameters and ive indol butiric acid (IBA) concentrations. Results have shown that pre-germination treatments are needed for Bocconia frutescens y Palicourea vaginata, in order to increase the probability and germination rate. On the other hand, shadow conditions are needed for Baccharis latifolia, Diplostephium rosmarinifolium, Drymis granadensis, Eupatorium angustifolium and Palicourea vaginata, as their seeds exhibit photoblastic characteristics. Due to the Cordia cylindrostachya and Palicourea linearifolia seed attack by insects (Lepidoptera and Hymenoptera) their sexual spread is highly limited. Finally, regarding the species response to the IBA and diameter combinations, each species responded in a different manner. Additionally, regarding the vegetative spread, the species Bocconia frutescens, Cordia cylindrostachya, Palicourea vaginata, Diplostephium rosmarinifolium and Drymis granadensis were very difficult to spread.

  5. TiO{sub 2} synthesized by the method of polymeric precursor (Pechini): structure of the intermediate resine; TiO{sub 2} sintetizado por el metodo de precursor polimerico (Pechini): estructura de la resina intermedia

    Energy Technology Data Exchange (ETDEWEB)

    Vargas, M. A.; Granco, Y.; Ochoa, Y.; Ortegon, Y.; Rodriguez Paez, J. E.

    2011-07-01

    In this work, the polymeric precursor method (Pechini method) was used to synthesize titanium dioxide. This process allowed a bigger control on the purity of the oxide and the crystalline phase present in the material. In this case, the principal phase was anatase. The resine obtained in this process was characterized using NMR and IR spectroscopy to determine their structure. With this information we proposed a resine structure model. To finish the process, the resin was thermally treated to obtain TiO{sub 2}. This oxide was characterized using different techniques: ray-X diffraction (RDX) and electron microscopy (TEM and SEM). The results indicated that the TiO{sub 2} anatase phase can be obtained at 450 degree centigrade with a particle size <100nm. (Author) 10 refs.

  6. Analysis of the extension and reduction method of qualified life used in equipment with ambiental qualification; Analisis del