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Sample records for automatizado para epr

  1. SAM - Sistema Automatizado del Método MECAP para Especificar Casos de Prueba

    Directory of Open Access Journals (Sweden)

    Kenyer Domínguez

    2010-12-01

    Full Text Available Existen cuatro elementos que son relevantes al momento de definir las pruebas: Confiabilidad, Costo, Tiempo y Calidad. El tiempo de desarrollo y el costo del producto se incrementan cuando se desean pruebas confiables y un software de calidad. Pero ¿qué se puede hacer para que los involucrados comprendan que las pruebas deben ser vistas como una red de seguridad? Si la calidad no se contempla antes de comenzar las pruebas, entonces ella no estará cuando se éstas terminen. El objetivo de este artículo es presentar la herramienta, SAM – Sistema Automatizado del Método MECAP que permite especificar Casos de Prueba a partir de Casos de Uso incorporando elementos que promueven la verificación y validación de la trazabilidad entre la Gestión de Requerimientos, el Análisis y Diseño y las Pruebas. SAM soporta el proceso de pruebas de forma automatizada, mejorando la confiabilidad de las mismas

  2. Sistema automatizado para la realización de pruebas funcionales a las protecciones electrónicas CELCOR

    Directory of Open Access Journals (Sweden)

    Rodolfo García Bermúdez

    2006-01-01

    Full Text Available Se realiza el diseño e implementación de un sistema automatizado que permite hacer las pruebas funcionales a las protecciones electrónicas por sobrecorriente para equipos de refrigeración producidas en el Laboratorio Científico Productivo perteneciente a la Universidad de Holguín "Oscar Lucero Moya". Para ello se realizó un estudio de las especificaciones funcionales que reclama el fabricante de las protecciones, que hizo posible definir un grupo de pruebas que verifican dichas especificaciones, se emplean módulos de adquisición de datos conectados por medio de una interfaz RS485 a la computadora y se hizo el diseño de la electrónica necesaria para la adaptación de las señales a estos módulos. El sistema informático permite realizar las pruebas a seis protecciones al mismo tiempo, cuyos resultados son almacenados en una base de datos. Adicionalmente puede realizarse la caracterización de los transformadores de corriente utilizados como sensores en las protecciones. El sistema realiza un grupo de pruebas que son imposibles de forma manual, eleva la productividad de los técnicos, disminuye los costos asociados al consumo de electricidad y permite que al 100% de las protecciones que salen al mercado se le verifiquen todas sus especificaciones funcionales.

  3. APLICACIÓN DE UN SISTEMA AUTOMATIZADO PARA LANZADORES DE PENALTY EN FÚTBOL

    Directory of Open Access Journals (Sweden)

    M.A. Martínez

    2010-09-01

    Full Text Available

     

    RESUMEN

    A pesar de reconocerse como la base del rendimiento de la mayoría de habilidades deportivas, pocos entrenadores reconocen que el funcionamiento de la visión es una habilidad aprendida susceptible de mejora. El objetivo principal de este estudio pretende medir la eficacia en goles y táctica individual de lanzadores expertos de penalty en fútbol utilizando un novedoso sistema automatizado de emisión de estímulos visuales aplicado en la situación habitual de campo. Lanzadores de penalty (n = 9 realizaron una prueba pre-tratamiento de 24 intentos en situación real frente a porteros (n = 3. Posteriormente, completaron un entrenamiento de 10 sesiones utilizando el sistema automatizado sin porteros y, finalmente, repitieron de nuevo la misma prueba inicial consiguiendo entonces significativamente más goles en la medida post-tratamiento. Además, se encontraron diferencias tácticas en base a la dirección de los lanzamientos respecto a la actuación del portero. Los resultados sugieren que el lanzamiento de penalty en fútbol puede plantearse como una habilidad motriz abierta, en función de la actuación del portero, reduciendo el tiempo de procesamiento de la información y de la toma de decisiones.
    PALABRAS CLAVE: Entrenamiento visual, lanzador, penalty, fútbol, expertos, toma de decisiones, control motor.

    ABSTRACT

    Despite recognising like the performance’s base of the majority of sports abilities, few trainers recognise that visual function is a learned ability that can be improved. The main aim of this study tries to measure efficacy in goals and individual tactic of high-skill penalty-kickers in soccer using a new automatic system of emission visual stimulus applied in the

  4. Sistema de gestión de citas y colas para dispositivos móviles : diseño para la gestión y control automatizado de tiempos de espera

    OpenAIRE

    Encinas Martín, Adolfo

    2012-01-01

    El objetivo de este proyecto es desarrollar un sistema capaz de proporcionar una solución completa e integral para el control de colas de citas en servicios que requieren de una reserva previa como pueden ser la seguridad social, un punto de información o la declaración de la renta, donde es frecuente que sus usuarios soporten largas esperas sin necesidad alguna. Así pues, este proyecto propone un sistema automatizado de avisos a dispositivos móviles de usuarios con cita reservada, mediante u...

  5. Diseño de un sistema de información automatizado para el mantenimiento preventivo total de la flota de vehículos de carga pesada. Caso: Sonidos Guayana, C. A.

    OpenAIRE

    Bossio Pittini, Lino Francisco

    2015-01-01

    Se presenta el diseño de un sistema de información automatizado para evaluación de los motores de la flota de camiones de Sonidos Guayana C.A. Con el fin de demostrar el correcto funcionamiento del sistema, se presentan las pruebas de adquisición, almacenamiento y análisis realizadas con éxito. Como mejoras futuras, se mencionan las recomendaciones que permiten la expansión del sistema.

  6. Aplicación de un sistema automatizado para el aprendizaje y el entrenamiento del tenis en condiciones de interferencia contextual

    Directory of Open Access Journals (Sweden)

    Ruperto Menayo Antúnez

    2009-06-01

    Full Text Available En este trabajo se presentan los efectos de la aplicación de un sistema automatizado para el aprendizaje del tenis en condiciones de interferencia contextual. Dicho sistema permite el registro de la precisión alcanzada en los golpeos mediante un protocolo de filmación audiovisual. Una vez filmadas las imágenes se aplica un proceso de digitalización para analizar el error variable de los envíos, determinando así la consistencia de los golpeos. Se analizaron los resultados obtenidos por 8 tenistas, tras un periodo de aprendizaje de 3 semanas, valorando el mantenimiento del rendimiento mediante 4 tests de retención, realizados posteriormente a la fase de aprendizaje inicial. Los resultados muestran mejoras en los cuatro golpes practicados tras el periodo de aprendizaje, así como una tendencia poco acusada de pérdida del rendimiento tras los periodos sin práctica.

  7. Sistema automatizado para la organización racional del proceso cosecha-transporte de cereales (SAORCE

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    Yanoy Morejón Mesa

    2014-01-01

    Full Text Available La presente investigacióntrata sobrela organización racional del proceso Cosecha-Transporte-Recepción (CTR de cereales. A partir de la necesidad que tienen las empresas productoras de cereales en Cuba y otros países, así como necesidad de agilizar, centralizar y dinamizar la organización racional de la composición de los medios mecanizados que intervienen en el proceso de forma automatizada, posibilitando reducir las pérdidas de tiempo en el ciclo de transportación, de recursos humanos y materiales propiciando ventajas económicas a través de la reducción de los costos implicados en la cadena productiva, incurriendo de este modo en una acertada toma de decisiones a cargo de los directivos. El presente trabajo tiene como objetivo general: implementar un sistema automatizado que gestione mediante la Teoría de Colas el carácter probabilístico, la composición racional y los parámetros técnicos y de explotación del flujo continuodel proceso de cosecha- transporte-recepción de cereales, asegurando el control, confiabilidad, integridad y disponibilidad de la información, así como una disminución considerable del tiempo de procesamiento de la información. Como principal resultado se puede mencionar la implementación de una aplicación software libre, multiplataforma que gestiona la composición racional del proceso a través del estudio probabilístico que proporciona ventajas considerables a los directivos. También brinda un conjunto de salidas y gráficos que permiten mejorar el análisis y distribución de la información.

  8. Diseño de un modelo de esquema director de un sistema de información gubernamental automatizado para paises en vías de desarrollo

    OpenAIRE

    Guillén Sarita, José Felipe

    1990-01-01

    Se plantea la posibilidad de elaborar un modelo de "Esquema Director" para el desarrollo de un Sistema de Información Gubernamental automatizado para países en vías de desarrollo. Así mismo,debido a la diversidad de países en vías de desarrollo se establece la necesidad de su estratificación con el fin de definir modelos para grupos de países con características similares. Con este propósito se selecciona la región de Centroamérica y El Caribe, estratificándose los países del área en...

  9. A simple automated procedure for thiol measurement in human serum samples Procedimento automatizado simples para determinação de tióis em amostras de soro humano

    Directory of Open Access Journals (Sweden)

    Carolina M. da Costa

    2006-10-01

    Full Text Available Thiol groups have been described as the main responsible for antioxidative effects of plasmatic proteins. Also, thiol serum levels have shown a positive correlation with total antioxidant capacity (TAC in many studies. Measurement of TAC by substract oxidation-based methods have been widely used as a reference to measure antioxidant status; however, in many cases these methods are inexact or imprecise, usually when performed by manual procedures. In this paper we describe a simple automated procedure for the determination of total thiols in serum, which was based on Ellman’s method. It was correlated with several markers of oxidative/antioxidative status, such as TAC and thiobarbituric acid reactive substance test (TBARs. Serum thiol levels were correlated positively with TAC (r = 0.298, p Os tióis são descritos como os principais responsáveis pelos efeitos antioxidantes das proteínas plasmáticas. Além disso, diversos estudos mostram uma correlação positiva entre os níveis séricos de tióis e a capacidade antioxidante total (CAT. A medida da CAT por métodos baseados na oxidação de substratos tem sido amplamente usada como referência na estimativa da capacidade antioxidante em amostras biológicas; porém, em muitos casos esses métodos são inexatos e imprecisos, principalmente quando realizados por procedimentos não-automatizados. Neste artigo descrevemos um procedimento automatizado simples para a determinação de tióis totais no soro, com base no conhecido método de Ellman. A dosagem dos tióis foi correlacionada com diversos marcadores da capacidade oxidante/antioxidante, como a CAT, o teste das substâncias reativas ao ácido tiobarbitúrico (TBARs e os níveis de peróxidos totais. Os tióis correlacionaram-se positivamente com a CAT (r = 0,298; p < 0,001 e negativamente com os níveis de TBARs (r = - 0,330; p < 0,001. O procedimento aqui descrito para a dosagem de tióis pode ser uma ferramenta importante na medida da

  10. Modelo geoespacial automatizado para la regionalización operativa en planeación de redes de servicios de salud Automated geospatial model for health services strategic planning

    Directory of Open Access Journals (Sweden)

    Juan Eugenio Hernández-Ávila

    2010-10-01

    Full Text Available Objetivo. Desarrollar un modelo automatizado de regionalización operativa para la planeación de las redes de servicios de salud propuestas en el Modelo Integrador de Atención a la Salud (MIDAS. Material y métodos. Con información disponible para México en 2005 y 2007 se realizó un modelo geoespacial para estimar el área potencial de influencia alrededor de cada unidad de atención médica, con base en el menor tiempo de viaje. Los resultados se compararon con un Estudio de Regionalización Operativa (ERO para Oaxaca llevado a cabo en 2005. Resultados. Comparado con el modelo geoespacial, el ERO asignó 48% de las localidades a centros de salud más lejanos y 23% de los centros de salud a hospitales más lejanos. Conclusiones. El modelo calculado en este estudio generó una regionalización más eficiente que el ERO de Oaxaca, minimizando el tiempo de viaje para el acceso a los servicios de salud. Este modelo ha sido adoptado por la Dirección General de Planeación y Desarrollo en Salud para la instrumentación del Plan Maestro Sectorial de Recursos para la Atención de la Salud.Objective. To develop an automated model for the operational regionalization needed in the planning of the health service networks proposed by the new Mexican health care model (Modelo Integrador de Servicios de Salud MIDAS. Material and Methods. Using available data for México during 2005 and 2007, a geospatial model was developed to estimate potential catchment areas around health facilities based on access travel time. The results were compared with an operational regionalization (ERO study manually carried out in Oaxaca with 2005 data. Results. The ERO assigned 48% of villages to health care centers further away than those assigned by the geospatial model, and 23% of these health centers referred patients to more distant hospitals. Conclusions. The model calculated by this study generated a more efficient regionalization than the ERO model, minimizing travel

  11. Sistema automatizado de medición de campo lejano

    OpenAIRE

    Morras, Cecilia Andrea; Bertone, Rodolfo Alfredo; De Vito, María Cecilia; Sanz, Juan Aurelio; Bria, Oscar N.

    2004-01-01

    El trabajo presenta y describe una propuesta para la definición de un sistema automatizado que permita generar mediciones de un campo lejano. Se entiende por campo lejano a la región del campo de una antena en la cual la distribución angular del campo es sensiblemente independiente de la distancia de la antena [12]. El problema en cuestión consiste en medir las polarizaciones de una antena en una banda de frecuencia. Dicha medición era realizada en forma manual, pudiéndose obtener un Diagr...

  12. Sistema Automatizado de Lectura Visual de Datos de Medida

    OpenAIRE

    ESTEBAN AVIVAR, ÁNGEL EUGENIO

    2013-01-01

    Adquisición de imágenes de un instrumento de medida con una webcam. Procesado y segmentación de esas imágenes para realizar una clasificación y obtener el dato medido. Image acquisition of a measuring instrument with a webcam. Processing and segmentation of these images for classifying and obtaining the measured data. Esteban Avivar, ÁE. (2013). Sistema Automatizado de Lectura Visual de Datos de Medida. http://hdl.handle.net/10251/33592. Archivo delegado

  13. Sistema automatizado de aquecimento solar para controle de fitopatógenos da água de irrigação Automatic solar heating system for control of pathogens in irrigation water

    Directory of Open Access Journals (Sweden)

    Carlos A. da S. Braga

    2001-05-01

    Full Text Available O sistema automatizado de aquecimento solar, baseou-se em um processo misto de aquecimento da água em circuito fechado, através de coletores planos e dois princípios integrados de transmissão de calor, um por convecção natural e o outro por convecção forçada. A automatização foi realizada por monitores termostáticos diferenciais. Os testes normativos abrangeram as temperaturas programadas de 50, 55 e 60 ºC, que contemplam a faixa de temperatura letal para a maioria dos fitopatógenos. Os resultados indicaram rendimentos térmicos da ordem de 63, 55 e 52%, superiores, quando comparados aos rendimentos médios de 50, 47 e 45% dos sistemas convencionais. Os resultados experimentais mostraram que o sistema é eficiente para a eliminação de patógenos da água de irrigação, sendo promissor como uma opção de baixo custo para ser usado em viveiros, casas-de-vegetação e pequenas ou médias propriedades agrícolas.In the system proposed, which uses flat collectors, both natural and forced convection are responsible for the transfer of heat to the circulating water. The automation of the system is performed by thermostats, placed in different places, electrically connected to other components like valves and a water pump. Under identical test conditions and in the range of temperatures considered (50, 55 and 60 ºC, which includes the reference lethal temperature range for pathogens, the thermal efficiencies attained were 63, 55 and 52%, which compare favorably with those obtained in conventional systems, these being 50, 47 and 42% respectively, as reported. The results of the experimental trials show that the system described is a viable option to eliminate pathogens present in irrigation water, while its low cost makes it attractive for use in nurseries, greenhouses and on small farms.

  14. Propuesta metodológica para construir sistemas automatizados de inspección visual industriales, con base en productos comerciales

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    Luis Diego Murillo

    2006-05-01

    Full Text Available Las compañías industriales que desean automatizar sus procesos de control de calidad, no deben arriesgar sus recursos en investigación y desarrollo para sus propios sistemas de visión industrial, debido a que esto implica invertir gran cantidad de tiempo y dinero para obtener los resultados deseados. En los últimos años, han surgido sistemas comerciales de inspección visual, los cuales se han convertido en una verdadera opción para quienes desean solucionar sus problemasconcernientes al aseguramiento de atributos de los productos. El presente artículo propone unametodología de 12 pasos, para construir un sistema de inspección visual automatizada (avi a partir de la selección e integración de distintos componentes comerciales.

  15. Sistema de información automatizado de recursos humanos para una institución de educación superior

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    Milagros Gómez de Gómez

    2004-01-01

    Full Text Available La presente propuesta es el diseño de un sistema de informacion para la direccion de recursos humanos de la Universidad Dr. Rafael Belloso Chacin, basado en los modelos teoricos planteados por sen, chiavenato, montilva, kendall y kendall. se contruyo sobre un diagnostico previo de la institucion en el cual participaron dos grupos: el primero construido por el personal directivo y el segundo por el personal administrativo.

  16. LIBRO ELECTRÓNICO MULTIMEDIA PARA EL DESARROLLO DE HABILIDADES EN EL MANEJO DE LOS SISTEMAS CONTABLES A TRAVÉS DE LA ASIGNATURA SISTEMAS AUTOMATIZADOS PARA EL CONTADOR

    OpenAIRE

    Omar Gómez Delgado; Lisbel Valera Fernández

    2009-01-01

    Las nuevas generaciones se ven inmersas en un contexto mediático y tecnológico más competitivo que demanda de forma inmediata nuevas habilidades y conocimientos del uso de las TICs y se supone que las personas deberían adquirir a través del proceso educativo un caudal de conocimientos y de competencias que las habiliten para continuar formándose a lo largo de la vida y para desempeñar diversas actividades, oficios o profesiones.

  17. Medición socio-técnica de las implementaciones de los sistemas de información automatizados

    OpenAIRE

    Estayno, Marcelo G.; Panizzi, Marisa D.

    2011-01-01

    El propósito de esta línea de investigación consiste en el diseño de una herramienta para la medición socio-técnica de las implementaciones de los sistemas de información automatizados. La herramienta propuesta medirá las necesidades de satisfacción de los usuarios afectados por el nuevo sistema de trabajo (sistema de información automatizado). La medición se basará en dos enfoques, un enfoque socio (social), fundamentado en técnicas y herramientas de las Ciencias del Comportamiento y un enfo...

  18. Application of an automated protocol for the analysis of the temporal parameters of the response of reaction tennis players during the execution of split-step and volley Aplicación de un protocolo automatizado para el análisis de los parámetros temporales de la respuesta de reacción en jugadores de tenis durante la ejecución de split-step y volea

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    V. Luis

    2010-09-01

    Full Text Available

    This study is aimed to show the design and application process of an automated system to recording in real time the temporary parameters of tennis players reaction response during the execution of the technical-tactical movement called “split-step and second volley”. The knowledge about temporary characteristics of the action will be make used of identify the variables to cause in that and also to design an investigation to permit an improvement of the tennis players efficiency in this sequence of the play. In this way, the use of the technological system will allow a precise analysis of player’s motor response and the eminent information about the defined action
    KEY WORDS: Tennis, split-step and volley, automated system of measure, reaction response

    El propósito de este trabajo consiste en mostrar el proceso de diseño y la aplicación de un sistema automatizado de medida para el registro en tiempo real de los parámetros temporales de la respuesta de reacción en jugadores de tenis durante la ejecución de una acción técnico-táctica denominada “split-step y segunda volea”. El conocimiento generado en cuanto a las características temporales de la acción se empleará para identificar las variables que determinan la eficacia en la misma y diseñar una investigación que permita optimizar el rendimiento de los tenistas en esta secuencia del juego. Así, el empleo de este sistema tecnológico permitirá un análisis preciso de la respuesta motriz de los jugadores y la extracción de información relevante acerca de la acción definida.
    PALABRAS CLAVE: Tenis, split-step y volea, sistema automatizado de medida, respuesta de reacción.

  19. Automatic system for blood donors control with seropositive results in epidemiological tests. Sistema automatizado para el control de donantes de sangre con resultados positivos a exámenes seroepidemiológicos

    Directory of Open Access Journals (Sweden)

    Nancy Piloto

    Full Text Available Background: Prevention of infectious diseases transmission through blood transfusion is one of the biggest challenges in the transfusion field of medicine. Objective: to design a computerized system for blood donors control with seropositive results in epidemiological tests. Methods: A system designed by the Provincial Blood Bank using Microsoft Access as a data base system and DELFHI 7 as associated language. It runs under Windows 2000 or any other superior system with 64 RAM and do not need special requirements of software or hardware. It includes the following data: Full name, age, sex, race, Id number, home address, number of the clinical record in the blood bank, date when the trial took place in each patient, kind of disease diagnosed, technical data of the trial such as: fluorescence, sectional level of the 1st trial as well as the repetition, name of the technician who performed it. Results: It permits to consult general data of donors as well as the disease diagnosed. It also permits to elaborate reports of these patients from any PC of the blood bank acceding with the security password of the program. Conclusions: It constitutes a beneficial tool which permits to improve the notification system established in the program of the web about sexually transmitted diseases from the Minister of Public Health in Cuba.

    Fundamento: La prevención de la transmisión de enfermedades infecciosas mediante la transfusión de sangre presenta uno de los desafíos más grandes para la medicina transfusional. Objetivo: Diseñar un sistema computarizado para el control de los donantes de sangre con resultados positivos a exámenes seroepidemiológicos. Métodos: Sistema diseñado en el banco Provincial de Sangre de Cienfuegos, con Microsoft Access como gestor de bases de datos y DELFHI 7 como lenguaje asociado; corre

  20. EPR imaging

    Science.gov (United States)

    Eaton, Sandra S.; Eaton, Gareth R.

    Useful EPR imaging has been achieved using simple gradient coils on a standard spectrometer. Resolution of less than 1 mm is possible without deconvolution of the resulting spectra. Examples are presented using DPPH and nitroxyl radicals.

  1. Soporte automatizado a la metodología web QEM

    OpenAIRE

    Papa, María Fernanda; Souto, M.E.; Rossi, Gustavo Héctor; Olsina Santos, Luis Antonio

    2001-01-01

    El soporte automatizado de muchas de las tareas en un proceso de evaluación permite minimizar esfuerzos y costos, como así también evitar errores e imprecisiones introducidas por el factor humano. El contar en el proceso de evaluación con una metodología cuantitativa que permita determinar un factor como calidad (o costo) de sitios y aplicaciones Web y, particularmente, el contar con herramientas de soporte a la misma es una de nuestras líneas de investigación y desarrollo. En el presente ...

  2. EPR response of sucrose and microcrystalline cellulose to measure high doses of gamma radiation; Respuesta EPR de sacarosa y celulosa micro cristalina para medir altas dosis de radiacion gamma

    Energy Technology Data Exchange (ETDEWEB)

    Torijano, E.; Cruz, L.; Gutierrez, G.; Azorin, J.; Aguirre, F. [Universidad Autonoma Metropolitana, Unidad Iztapalapa, Av. San Rafael Atlixco 186, Col. Vicentina, 09340 Mexico D. F. (Mexico); Cruz Z, E., E-mail: eftc@xanum.uam.mx [UNAM, Instituto de Ciencias Nucleares, Circuito Exterior, Ciudad Universitaria, 04510 Mexico D. F. (Mexico)

    2015-10-15

    Solid dosimeters of sucrose and microcrystalline cellulose (Avicel Ph-102) were prepared, following the same process, in order to compare their EPR response against that of the l-alanine dosimeters considered as reference. All lots of dosimeters were irradiated with gamma radiation in Gamma beam irradiator with 8 kGy/h of the Nuclear Sciences Institute of UNAM. Doses ranged from 1 to 10 kGy respectively. We found that both the response of sucrose as microcrystalline cellulose were linear; however, the response intensity was, on average, twenty times more for sucrose. Comparing this against the EPR response of l-alanine in the range of doses, it was found that the response to sucrose is a third part; and microcrystalline cellulose is a sixtieth, approximately. The results agree with those found in the literature for sucrose, leaving open the possibility of investigating other dosage ranges for cellulose. (Author)

  3. La medida de la eficiencia económica de las inversiones en sistemas automatizados de gestión productiva, SAGP

    Directory of Open Access Journals (Sweden)

    Bernardo Parra Restrepo

    1997-06-01

    Full Text Available Este artículo presenta una idea general de los sistemas automatizados de gestión productiva cuya aplicación industrial ha sido una tendencia irreversible en los últimos años. También propone una metodología para la medición de la eficiencia económica aplicable a las inversiones hechas en automatización y sistematización de procesos industriales y administrativos. De manera simple se entiende por eficiencia económica el cálculo de la relación existente entre los costos de producción de cada unidad producida y los beneficios económicos obtenidos. Los sistemas automatizados de gestión productiva SAGP, son estructuras mixtas complejas integradas por el hombre y dispositivos técnicos compuestos por máquinas calculadoras de alta velocidad, conexos con dispositivos de dirección de medios electrónicos y mecánicos adaptados a la planificación, ejecución, medición y control de procesos de producción que se localizan generalmente en las fases de generación de energía, transmisión, manufactura y ensamble de productos.

  4. El Portafolio Digital como estrategia didáctica: la experiencia del curso Servicios de Información Automatizados

    Directory of Open Access Journals (Sweden)

    Ginnette Calvo Guillén

    2014-01-01

    Full Text Available En esta investigación se presenta una experiencia de implementación del Portafolio Digital como estrategia didáctica en dos grupos del curso Servicios de Información Automatizados, pertenecientes al segundo año del tronco común de las carreras de Bachillerato de la Escuela de Bibliotecología y Ciencias de la Información de la Universidad de Costa Rica. La estrategia fue desarrollada individualmente y tuvo como objetivos construir un sitio web como espacio de reflexión acerca de los aprendizajes alcanzados durante el curso, así como crear un servicio de información para desarrollar destrezas evaluando y seleccionando fuentes de información confiables en línea. Con la estrategia se logró que el estudiantado concientizara sobre su responsabilidad en el proceso de construcción del conocimiento y permitió la realimentación recíproca, así como la identificación de fuentes de información confiables en línea.

  5. Desarrollo de un sistema de riego automatizado en tiempo real con base en balance hídrico climático, medición de humedad del suelo y lisímetro

    OpenAIRE

    Castro Popoca, Martiniano

    2012-01-01

    Se desarrollo un sistema de riego automatizado en tiempo real, para determinar y controlar el momento oportuno y la cantidad de riego, monitoreado por medio de las tecnologías de información (TI). El estudio se realizó en los terrenos adjuntos a la estación meteorológica del Colegio de Postgraduados del Campus Montecillo, del 10 de junio al 11 de septiembre del 2006. El sistema se integró de un programa de cómputo en el lenguaje de programación Edlog y un dispositivo de co...

  6. Medical application of EPR

    International Nuclear Information System (INIS)

    Selected applications of continuous-wave EPR in medicine are reviewed. This includes detection of reactive oxygen and nitrogen species, pH measurements and oxymetry. Applications of EPR imaging are demonstrated on selected examples and future developments to faster imaging methods are discussed

  7. Estacionamiento Automatizado con Tecnología RFID

    Directory of Open Access Journals (Sweden)

    Eric León Olivares

    2011-01-01

    Full Text Available Este artículo presenta un proyecto que resuelve el problema del acceso al estacionamiento vehicular del Instituto Tecnológico de Pachuca ya que se realiza de manera manual, presentando un descontrol y bajo nivel de seguridad en el mismo, su automatización brinda las herramientas necesarias, por medio de la tecnología RFID, para mejorar el nivel de seguridad en la entrada/ salida de los automóviles, aumentar el control de los usuarios al tener su información almacenada en una base de datos y con ello poder elaborar reportes, estadísticas y otros materiales que se requieran para ser estudiados.

  8. Procedimiento para el ensayo de antimicrobianos frente a bacterias que crecen en biocapas

    OpenAIRE

    Amorena Zabalza, Beatriz; Gracia Currás, Elena; Conchello Moreno, Pilar; Fernández Casanovas, Antonio

    1998-01-01

    Procedimiento para el ensayo de antimicrobianos frente a bacterias que crecen en biocapas. Esta patente describe un nuevo método automatizado para determinar la efectividad de antimicrobianos frente a bacterias adheridas a superficies y que crecen formando biocapas (biofilms). Es aplicable a los sectores farmacológico y de microbiología clínica.

  9. Biomolecular EPR spectroscopy

    CERN Document Server

    Hagen, Wilfred Raymond

    2008-01-01

    Comprehensive, Up-to-Date Coverage of Spectroscopy Theory and its Applications to Biological SystemsAlthough a multitude of books have been published about spectroscopy, most of them only occasionally refer to biological systems and the specific problems of biomolecular EPR (bioEPR). Biomolecular EPR Spectroscopy provides a practical introduction to bioEPR and demonstrates how this remarkable tool allows researchers to delve into the structural, functional, and analytical analysis of paramagnetic molecules found in the biochemistry of all species on the planet. A Must-Have Reference in an Intrinsically Multidisciplinary FieldThis authoritative reference seamlessly covers all important bioEPR applications, including low-spin and high-spin metalloproteins, spin traps and spin lables, interaction between active sites, and redox systems. It is loaded with practical tricks as well as do's and don'ts that are based on the author's 30 years of experience in the field. The book also comes with an unprecedented set of...

  10. Rapid Frequency Scan EPR

    OpenAIRE

    Tseitlin, Mark; Rinard, George A.; Quine, Richard W.; Eaton, Sandra S.; Eaton, Gareth R.

    2011-01-01

    In rapid frequency scan EPR with triangular scans, sufficient time must be allowed to insure that the magnetization in the x,y plane decays to baseline at the end of the scan, which typically is about 5 T2 after the spins are excited. To permit relaxation of signals excited toward the extremes of the scan the total scan time required may be much longer than 5 T2. However, with periodic, saw-tooth excitation, the slow-scan EPR spectrum can be recovered by Fourier deconvolution of data recorded...

  11. EPR paradox revisited

    International Nuclear Information System (INIS)

    In a seminal paper from 1935 Einstein, Podolsky and Rosen produced one of the most powerful weapon against the unpredictability of the world ensured by quantum mechanics. The recent production of entangled states, with all its possible future applications in quantum computation, re-open the possibility of testing EPR states on physical grounds. The present intends to present a challenge to the wedding of classical (special) relativity with quantum mechanics, the so called relativistic quantum mechanics. Making use of the same apparatus devised in EPR, it is shown that non local quantum states are incompatible with either their possibility of being measured or else with Lorentz invariance (or even with both). (author)

  12. EPR paradox revisited

    Energy Technology Data Exchange (ETDEWEB)

    Klippert, R. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil)

    1999-07-01

    In a seminal paper from 1935 Einstein, Podolsky and Rosen produced one of the most powerful weapon against the unpredictability of the world ensured by quantum mechanics. The recent production of entangled states, with all its possible future applications in quantum computation, re-open the possibility of testing EPR states on physical grounds. The present intends to present a challenge to the wedding of classical (special) relativity with quantum mechanics, the so called relativistic quantum mechanics. Making use of the same apparatus devised in EPR, it is shown that non local quantum states are incompatible with either their possibility of being measured or else with Lorentz invariance (or even with both). (author)

  13. Automated Recognition of Bioacoustic Signals: a Review of Methods and Applications Reconocimiento automatizado de señales bioacústicas: Una revisión de métodos y aplicaciones

    Directory of Open Access Journals (Sweden)

    Paula Catalina Caycedo-Rosales

    2013-11-01

    Full Text Available During the past decade, numerous research studies and applications on automated bioacoustic monitoring have been published; however, such studies are scattered in the literature of engineering and life sciences. This paper presents a review on fundamental concepts of automated acoustic monitoring. Our aim is to compare and categorize —in a taxonomy of techniques DSP/PR— the contributions of published research studies and applications; in order to suggest some directions for future research and highlight challenges and opportunities related to the deployment of this technology in Colombia.Durante la última década se ha publicado una gran cantidad de estudios de investigación y aplicaciones sobre monitoreo bioacústico automatizado. No obstante, tales estudios están dispersos en la literatura de ingeniería y ciencias biológicas. En este artículo se presentan conceptos fundamentales sobre monitoreo bioacústico automatizado; se revisan, comparan y categorizan —en una taxonomía de técnicas de DSP/PR— las contribuciones de las investigaciones y las aplicaciones publicadas; se sugieren algunas direcciones para investigaciones futuras y se resaltan los retos y las oportunidades relacionados con la instalación de esta tecnología en Colombia.

  14. EPR: the nuclear impasse

    International Nuclear Information System (INIS)

    The questions relative to the climatic change constitute crucial challenges for the next ten years. In this context the author aims to show how the EPR project illustrates the nuclear french ''autism''. He presents and analyzes the international and environmental impacts of this obsolete technology, as a project useless and dangerous. (A.L.B.)

  15. Migración de sistemas automatizados: política y gestión del cambio en bibliotecas

    Directory of Open Access Journals (Sweden)

    Ballester, Josefina

    1995-09-01

    Full Text Available In order to survive, libraries must be able to adapt -flexibly, efficiently and responsively- to user needs. New technological developments serve to help libraries adjust to their new challenges and this is one of the reasons that leads them to migrate from one automated system to another. Implementing a new system is a complex process, owing to the new features being introduced and to the need to migrate data from the first system. This article analyzes why, how and when systems are changed, and includes guidelines for managing the transition: objectives, needs analyses, elaboration of technical specifications, and evaluation. Once the new system is chosen, the management of change begins and involves both the library management and library staff. Finally, the importance of staff participation in the entire process is discussed, including training and channels of communication.

    Las bibliotecas, para poder sobrevivir, han de adaptarse a las demandas de los usuarios, de una manera más flexible, sensible y eficaz. Los nuevos desarrollos tecnológicos ayudan a la biblioteca a adecuarse a sus nuevas necesidades, y es por ello por lo que más frecuentemente se produce el cambio de un sistema automatizado a otro. La implementación de un segundo sistema es un proceso más complejo, debido a las nuevas prestaciones que se incorporan y al tener que migrar los datos ya existentes en el primer sistema. En este artículo se analiza el por qué, el cómo y el cuándo del cambio de sistema, así como las líneas de actuación previas que se han de seguir antes de iniciar el cambio: objetivos, análisis de necesidades, definición de especificaciones técnicas y evaluación. Una vez elegido el producto, se inicia la gestión del cambio que involucra tanto a la dirección para que lo controle, como al personal que actúa como agente del cambio. Por último, se analiza el papel tan importante que juega, en el éxito del nuevo sistema, la participaci

  16. Desenvolvimento de um sistema automatizado para a fabricação de filmes automontados

    Directory of Open Access Journals (Sweden)

    Trivinho-Strixino Francisco

    2004-01-01

    Full Text Available In this technical note, we describe the construction of a low-cost computer controlled device for layer-by-layer film fabrication. The software allows to control multiple material deposition, washing and drying steps and the time for each operation. To test the device, we produced and characterized self-assembled films of conductive polymers by alternating poly(o-methoxyaniline (POMA and poly(3-thiophene acetic acid (PTAA via the layer-by-layer technique.

  17. Rapid frequency scan EPR.

    Science.gov (United States)

    Tseitlin, Mark; Rinard, George A; Quine, Richard W; Eaton, Sandra S; Eaton, Gareth R

    2011-08-01

    In rapid frequency scan EPR with triangular scans, sufficient time must be allowed to insure that the magnetization in the x, y plane decays to baseline at the end of the scan, which typically is about 5T(2) after the spins are excited. To permit relaxation of signals excited toward the extremes of the scan the total scan time required may be much longer than 5T(2). However, with periodic, saw-tooth excitation, the slow-scan EPR spectrum can be recovered by Fourier deconvolution of data recorded with a total scan period of 5T(2), even if some spins are excited later in the scan. This scan time is similar to polyphase excitation methods. The peak power required for either polyphase excitation or rapid frequency scans is substantially smaller than for pulsed EPR. The use of an arbitrary waveform generator (AWG) and cross loop resonator facilitated implementation of the rapid frequency scan experiments reported here. The use of constant continuous low B(1), periodic excitation waveform, and constant external magnetic field is similar to polyphase excitation, but could be implemented without the AWG that is required for polyphase excitation. PMID:21664848

  18. Broadband transmission EPR spectroscopy.

    Directory of Open Access Journals (Sweden)

    Wilfred R Hagen

    Full Text Available EPR spectroscopy employs a resonator operating at a single microwave frequency and phase-sensitive detection using modulation of the magnetic field. The X-band spectrometer is the general standard with a frequency in the 9-10 GHz range. Most (biomolecular EPR spectra are determined by a combination of the frequency-dependent electronic Zeeman interaction and a number of frequency-independent interactions, notably, electron spin - nuclear spin interactions and electron spin - electron spin interactions, and unambiguous analysis requires data collection at different frequencies. Extant and long-standing practice is to use a different spectrometer for each frequency. We explore the alternative of replacing the narrow-band source plus single-mode resonator with a continuously tunable microwave source plus a non-resonant coaxial transmission cell in an unmodulated external field. Our source is an arbitrary wave digital signal generator producing an amplitude-modulated sinusoidal microwave in combination with a broadband amplifier for 0.8-2.7 GHz. Theory is developed for coaxial transmission with EPR detection as a function of cell dimensions and materials. We explore examples of a doublet system, a high-spin system, and an integer-spin system. Long, straigth, helical, and helico-toroidal cells are developed and tested with dilute aqueous solutions of spin label hydroxy-tempo. A detection limit of circa 5 µM HO-tempo in water at 800 MHz is obtained for the present setup, and possibilities for future improvement are discussed.

  19. Electron paramagnetic resonance (EPR) biodosimetry

    International Nuclear Information System (INIS)

    Radiation-induced electron paramagnetic resonance (EPR) signals were first reported by Gordy et al. [Proc. Natl. Acad. Sci. USA 41 (1955) 983]. The application of EPR spectroscopy to ionizing radiation dosimetry was later proposed by Brady et al. [Health Phys. 15 (1968) 43]. Since that time EPR dosimetry has been applied to accident and epidemiologic dose reconstruction, radiation therapy, food irradiation, quality assurance programs and archaeological dating. Materials that have been studied include bone, tooth enamel, alanine and quartz. This review paper presents the fundamentals and applications of EPR biodosimetry. Detailed information regarding sample collection and preparation, EPR measurements, dose reconstruction, and data analysis and interpretation will be reviewed for tooth enamel. Examples of EPR biodosimetry application in accidental overexposures, radiopharmaceutical dose assessment and retrospective epidemiologic studies will also be presented

  20. Quantitative EPR A Practitioners Guide

    CERN Document Server

    Eaton, Gareth R; Barr, David P; Weber, Ralph T

    2010-01-01

    This is the first comprehensive yet practical guide for people who perform quantitative EPR measurements. No existing book provides this level of practical guidance to ensure the successful use of EPR. There is a growing need in both industrial and academic research to provide meaningful and accurate quantitative EPR results. This text discusses the various sample, instrument and software related aspects required for EPR quantitation. Specific topics include: choosing a reference standard, resonator considerations (Q, B1, Bm), power saturation characteristics, sample positioning, and finally, putting all the factors together to obtain an accurate spin concentration of a sample.

  1. EPR design for maintenance

    International Nuclear Information System (INIS)

    Preventive maintenance is very important in achieving high plant availability. For the European Pressurized Reactor (EPR) preventive maintenance has been carefully addressed in the design stage. This is particularly necessary because of the traditionally different maintenance strategies employed in France and Germany. This paper emphasizes the following features introduced in the ERP design to minimize the duration of the refueling outage: (1) containment accessibility during power operation; (2) overall plant layout to facilitate inspections and maintenances within the containment; and (3) safety system design for enabling preventive maintenance during power operation. (author)

  2. The EPR reactor NDE

    International Nuclear Information System (INIS)

    In May 2006, Electricite de France decided to launch the building of the first EPRR Reactor on the Flamanville site in Normandy. The 'Flamanville 3' EPR unit is the first one to be subjected to the French Ministerial Orders of the 10 November 1999 and of the 13 December 2005 from the design phase. According to these orders, the non destructive examination (NDE) planned for the in service inspection (ISI) and for the pre service inspection (PSI) must be operational with a compulsory formal qualification. The PSI is a complete inspection of the main primary and secondary systems. The PSI's objective is to perform before the first core loading all the NDE planned for the future ISI in the same conditions, in order to have a reliable reference for the detection or for the evaluation of the possible damages during the ISI. The 'Flamanville 3' PSI is planned to start end 2010. The program consists of the development and the qualification of the NDE compatible with this new generation reactor's challenges. The paper is about: - the main EPR's objectives and the technological evolutions, - the main component modifications (which have an impact on the NDE), - the place of ISI in the general safety demonstration, - the main inspection objectives, - the NDE qualification process, - the approach to set up the ISI program, - the ISI program. (authors)

  3. Presentation of EPR

    International Nuclear Information System (INIS)

    In 1989, Framatome and Siemens decided to associate for the design of a new type of nuclear power plant and created the Nuclear Power International joint venture. In 1992, Electricite de France (EdF) and the principal German electric power companies decided to join this project which was called EPR (European Pressurized water Reactor). To answer the main objectives of the project, licensing in both countries and competitiveness with other energy sources, the different design philosophies which were developed on both side of the Rhine river had to merge. In parallel with this design work, the French and German safety authorities have enhanced their cooperation already started to draw the safety requirements of future reactors. At this stage of the conceptual design phase, the project is in the right way to satisfy both objectives. Cost evaluations show that EPR will be able to provide electric power with a price competitive with other energy sources. Thanks to the fruitful cooperation between Framatome, Siemens, NPI and EdF CNEN and to the good relationships between safety authorities, noticeable results have been obtained. This is not simply due to the juxtaposition of existing solutions but by associating the best solutions to provide a new optimized conception. (J.S.). 3 figs., 1 tab

  4. The EPR layout design

    International Nuclear Information System (INIS)

    The European Pressurised Water Reactor (EPR), is a French-German development for the next generation of Pressurised Water Reactor. The new reactor is based on the experiences of operation and design of nuclear power plants in both countries. The EPR fulfils enhanced safety standards, higher availability and a longer service life. Layout and safety aspects All Nuclear Island (NI) buildings are designed against design earthquake as well as explosion pressure i wave. The protection against Airplane Crash (APC), can be realised through civil and layout possibilities. The Reactor Building, the Safeguard Buildings division 2 and 3 and the Fuel Building are protected by concrete structures. The other nuclear buildings are protected by geographical separation. Important safety requirements are the further reduction of the probability of severe accidents and the mitigation of such accident on the plant area. For that, a spreading area for molten corium, a channel from the reactor pit to the spreading area and the In Containment Refuelling Water Storage tank (IRWST) for flooding and initial cooling of the corium, were implemented in the design of the Reactor Building. All NI buildings with their main routings were designed in a 3D model. The utility design reviews were performed with this model. (author)

  5. EPR of uranium ions

    International Nuclear Information System (INIS)

    A review of the electron paramagnetic resonance data on the uranium ions is given. After a general account of the electronic structure of the uranium free atoms and ions, the influence of the external fields (magnetic field, crystal fields) is discussed. The main information obtained from EPR studies on the uranium ions in crystals are emphasized: identification of the valence and of the ground electronic state, determination of the structure of the centers, crystal field effects, role of the intermediate coupling and of the J-mixing, role of the covalency, determination of the nuclear spin, maqnetic dipole moment and electric quadrupole moment of the odd isotopes of uranium. These data emphasize the fact that the actinide group has its own identity and this is accutely manifested at the beginning of the 5fsup(n) series encompassed by the uranium ions. (authors)

  6. EPR Flamanville 3, Site Management

    International Nuclear Information System (INIS)

    Antoine Menager, the EPR Flamanville 3 Site Manager described the organization and the management of the Flamanville site during the construction phase. He placed emphasis on Health and Safety, Environmental and Social Responsibility and on Nuclear Safety and Quality

  7. Reconsidering Bohr's reply to EPR

    OpenAIRE

    Halvorson, Hans; Clifton, Rob

    2001-01-01

    Although Bohr's reply to the EPR argument is supposed to be a watershed moment in the development of his philosophy of quantum theory, it is difficult to find a clear statement of the reply's philosophical point. Moreover, some have claimed that the point is simply that Bohr is a radical positivist. In this paper, we show that such claims are unfounded. In particular, we give a mathematically rigorous reconstruction of Bohr's reply to the \\emph{original} EPR argument that clarifies its logica...

  8. EPR by Areva. EPR the 1600+ MWe reactor

    International Nuclear Information System (INIS)

    This brochure presents the GEN III+ EPR reactor designed by the Areva and Siemens consortium. The EPR reactor is a direct descendent of the well-proven N4 and KONVOI reactors, the most modern reactors in France and Germany. The EPR was designed by teams from KWU/Siemens and Framatome, EDF in France and the major German utilities, working in collaboration with both French and German safety authorities. The EPR integrates the results of decades of R and D programs, in particular those performed by the CEA (French Atomic Energy Commission) and the Karlsruhe Research Center in Germany. The EPR benefits from the experience of several thousand reactor-years of operation of pressurized water reactor technology. This experience has put 87 AREVA PWRs online throughout the world. Innovative Features: - An outer shell covering the reactor building, the spent fuel building and two of the four safeguard buildings provides protection against large commercial or military aircraft crash. - A heavy neutron reflector that surrounds the reactor core lowers uranium consumption. - An axial economizer inside the steam generator allows a high level of steam pressure and therefore high plant efficiency. - A core catcher allows passive collection and retention of the molten core should the reactor vessel fail in the highly unlikely event of a core melt. - A digital technology and a fully computerized control room with an operator friendly man-machine interface improve the reactor protection system

  9. Comparison of semi-automatized assays for anti-T. gondii IgG detection in low-reactivity serum samples: importance of the results in patient counseling Comparação de ensaios semi-automatizados para pesquisa de IgG anti-T. gondii em amostras de soros de baixa reatividade: importância dos resultados no aconselhamento do paciente

    Directory of Open Access Journals (Sweden)

    Paulo Guilherme Leser

    2003-06-01

    Full Text Available Toxoplasmosis is a disease which can cause severe congenital infection and is normally diagnosed by the detection of T. gondii specific antibodies in the serum of infected patients. Several different tests allow to distinguish recent from past infections and to quantify anti-T. gondii specific IgG, and the results can be used as markers for immunity. In the present study, we compare the performance of two different methodologies, the Elfa (bioMérieux S.A and the Meia (Abbott Laboratories in detecting T. gondii specific IgG in low-reactivity sera. Of 76 analyzed samples, three presented discrepant results, being positive in the Abbott AxSYM Toxo IgG assay, and negative in the bioMérieux Vidas Toxo IgG II assay. By using other tests, the three sera were confirmed to be negative. The results are discussed in the context of their importance for patient management, especially during pregnancy.Toxoplasmose, doença conhecida por sua severidade na infecção congênita é geralmente diagnosticada pela demonstração de anticorpos específicos contra antígenos de T. gondii, presentes no soro de indivíduos infectados. Diferentes testes são disponíveis para diferenciar infecção recente de infecção pregressa, para quantificar anticorpos IgG anti-T. gondii nos soros dos pacientes e utilizar os resultados como marcadores de imunidade. Neste trabalho apresentamos os resultados do estudo comparativo de duas tecnologias, Elfa (bioMérieux S.A. e Meia (Abbott Laboratories, para pesquisa de anticorpos IgG anti-T. gondii em amostras de soros de baixa reatividade. De 76 amostras processadas, três apresentaram resultados discrepantes, reagentes para AxSYM Toxo IgG e não-reagentes para Vidas Toxo IgG II. A confirmação dos resultados, feita por bateria de testes, mostrou que todas as três amostras eram não-reagentes. Os resultados são discutidos em sua importância e orientação clínica, principalmente para a paciente gestante.

  10. The EPR layout design

    International Nuclear Information System (INIS)

    General: The European Pressurised Water Reactor (EPR) is a French - German development for the next generation of Pressurised Water Reactor. The new reactor design is based on the experiences of operation and design of nuclear power plants in both countries. The EPR fulfils enhanced safety standards, higher availability and a longer service life. Utilities aspects: For the Utilities one important requirement is the reduction of personnel exposure during maintenance and in-service inspection. The other significant requirement is of economic nature. The main points influencing costs, which have also impact on the layout, are: outage times, accessibility of the reactor building and the available maintenance and set down areas. The Utilities have also required to load the spent fuel assemblies into the shipping cask from the bottom of the fuel pool, because of the exclusion of the drop of the cask and in order to avoid contamination at the outer cask shell. Layout and safety aspects: All safety relevant Nuclear Island (NI) buildings are designed against design earthquake as well as explosion pressure wave. The protection against Airplane Crash (APC) is realised by civil and layout dispositions. The Reactor Building, the Safeguard Buildings division 2 and 3 and the Fuel Building are protected by concrete structures. The other safety relevant nuclear buildings are protected by geographical separation. Important safety requirements are the further reduction of the probability of severe accidents and the mitigation of such an accident on the plant area. For that, a spreading area for molten corium, a channel from the reactor pit to the spreading area and the In Containment Refuelling Water Storage Tank (IRWST) for flooding and initial cooling of the corium, were implemented in the design of the Reactor Building. Layout results: The following buildings are arranged on a common raft to protect them against design earthquake: Reactor Building (RB), Safeguard Buildings (SAB

  11. Planar microresonators for EPR experiments

    Science.gov (United States)

    Narkowicz, R.; Suter, D.; Stonies, R.

    2005-08-01

    EPR resonators on the basis of standing-wave cavities are optimised for large samples. For small samples it is possible to design different resonators that have much better power handling properties and higher sensitivity. Other parameters being equal, the sensitivity of the resonator can be increased by minimising its size and thus increasing the filling factor. Like in NMR, it is possible to use lumped elements; coils can confine the microwave field to volumes that are much smaller than the wavelength. We discuss the design and evaluation of EPR resonators on the basis of planar microcoils. Our test resonators, which operate at a frequency of 14 GHz, have excellent microwave efficiency factors, achieving 24 ns π/2 EPR pulses with an input power of 17 mW. The sensitivity tests with DPPH samples resulted in the sensitivity value 2.3 × 10 9 spins · G -1Hz -1/2 at 300 K.

  12. Reconsidering Bohr's reply to EPR

    CERN Document Server

    Halvorson, H; Halvorson, Hans; Clifton, Rob

    2001-01-01

    Although Bohr's reply to the EPR argument is supposed to be a watershed moment in the development of his philosophy of quantum theory, it is difficult to find a clear statement of the reply's philosophical point. Moreover, some have claimed that the point is simply that Bohr is a radical positivist. In this paper, we show that such claims are unfounded. In particular, we give a mathematically rigorous reconstruction of Bohr's reply to the \\emph{original} EPR argument that clarifies its logical structure, and which shows that it does not rest on questionable philosophical assumptions. Rather, Bohr's reply is dictated by his commitment to provide "classical" and "objective" descriptions of experimental phenomena.

  13. The EPR in a few words: all you need to know about the EPR nuclear reactor

    International Nuclear Information System (INIS)

    After a brief presentation of the EPR (European - or Evolutionary - Pressurized Reactor) type nuclear reactor, this paper, proposed by the collective group 'Stop EPR', develops the following points: EPR is as dangerous as other reactors; EPR flouts democracy; France's energy demand do not need the construction of EPRs; the construction of EPRs is not a factor of economical and social development; EPR should not be constructed neither in France nor elsewhere and the present building sites should be cancelled; the EPR will not help France to increase its energy independence and protect itself from oil price increases; choosing the EPR is incompatible with the large investments to be made in energy conservation and renewable energies; the EPR is not a solution to climate change; the VHV line corridor that will starts at Flamanville is not justified and poses risks to the environment and public health

  14. EPR: the nuclear impasse; EPR: l'impasse nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Marillier, F. [Association Ecologiste Greenpeace (France)

    2008-07-01

    The questions relative to the climatic change constitute crucial challenges for the next ten years. In this context the author aims to show how the EPR project illustrates the nuclear french ''autism''. He presents and analyzes the international and environmental impacts of this obsolete technology, as a project useless and dangerous. (A.L.B.)

  15. EPR in B physics and elsewhere

    International Nuclear Information System (INIS)

    The application of Einstein-Podolsky-Rosen correlations in Υ(4s) → B anti B decays to research in CP violation is the first and probably only use of EPR as a technique for research in new physics. Elsewhere highly sophisticated EPR projects question EPR and test its predictions to look for violations of quantum mechanics, hidden variables, Bell''s inequalities, etc

  16. Software para generación de cuestionarios

    OpenAIRE

    Banco Interamericano de Desarrollo (BID); Departamento Administrativo Nacional de Estadística (DANE)

    2008-01-01

    La presentación muestra el sistema informático completo y los procesos utilizados por el Departamento Administrativo Nacional de Estadística de Colombia para el relevamiento y procesamiento de datos y para la generación de información. Luego, se describe en detalle y a través de capturas de pantalla las características y funcionalidades del software para la gestión de los datos (GEA) que permite generar cuestionarios automatizados.

  17. EPR study of human hair

    Czech Academy of Sciences Publication Activity Database

    Křížová, Jana; Káfuňková, Eva; Stopka, Pavel

    2005-01-01

    Roč. 99, č. 14 (2005), s. 217-218. ISSN 0009-2770 R&D Projects: GA MZd(CZ) NL7567; GA MZd(CZ) NB7377 Institutional research plan: CEZ:AV0Z40320502 Keywords : EPR Subject RIV: CA - Inorganic Chemistry Impact factor: 0.445, year: 2005

  18. The EPR for North America

    International Nuclear Information System (INIS)

    As the supplier of 30 percent of the world's nuclear generating capacity, Framatome ANP, an AREVA and, Siemens company, has been a major contributor in the development of today's international fleet of nuclear power plants. Additionally, as a member of the AREVA global family of companies, Framatome ANP is a major element of the world's largest vertically integrated nuclear supplier. The EPR is the latest evolutionary pressurized water reactor design developed by Framatome ANP. The EPR benefits from the global operating experience of the international fleet of nuclear reactors. Framatome ANP is continuing to play a leadership role in the global renaissance of nuclear power. In December 2003, a Framatome ANP and Siemens consortium signed a firm price, turn-key contract with the Finnish utility TVO for an EPR to be constructed at the Olkiluoto site, In October 2004, it was announced that France would build its first EPR at the Flamanville site as a demonstration plant for a future series of advanced nuclear plants. In February 2005, Framatome ANP submitted a proposal for the supply of four EPR's in China which would be the beginning of a series of new construction in that country. Momentum is also building for new nuclear plants in Canada. Many reports in the past year, including those published by the Canadian Energy Research Institute, indicate that new electricity supplies will be required to meet the growing energy needs of Canada, especially in Ontario. The shutdown of approximately 7,000 MWe of coal-fired generation in Ontario by 2007 will further complicate the energy supply situation. Furthermore, various reports indicate as much as 24,000 MWe of new Canadian electricity generation could be required by 2020. Due to this developing potentially large electricity supply-demand imbalance, some industry officials believe the first North American order for a new nuclear plant will be placed in Canada. It is not surprising then that Framatome ANP is focusing on

  19. Complicações iniciais do uso de dois microceratótomos automatizados Initial complications of two automated microkeratomes

    Directory of Open Access Journals (Sweden)

    Monica do Carmo Passos

    2001-06-01

    Full Text Available Objetivo: Descrever as complicações per e pós-operatórias ocorridas durante o uso inicial de dois microceratótomos automatizados na realização de LASIK. Métodos: Estudo retrospectivo das primeiras cirurgias realizadas com dois microceratótomos automatizados, sendo 70 olhos de 54 pacientes utilizando o microceratótomo da Chiron® modelo Automated Corneal Shaper (ACS, no período de abril de 1997 a abril de 1998 e 100 olhos de 82 pacientes com o microceratótomo automatizado Moria® Carriazo-Barraquer (CB, durante o período de fevereiro de 1999 a junho de 1999. A fotoablação foi realizada com excimer laser de fluoreto de argônio de 193 nm da Summit modelo Apex Plus®. Foram avaliadas as complicações per e pós-operatórias até um mês de seguimento. Resultados: A fotoablação não foi realizada em 3 casos (4,3% usando-se o microceratótomo ACS e em 1 caso (1% usando o microceratótomo CB. As complicações mais freqüentemente encontradas com o ACS foram: falha no retorno automatizado do microceratótomo (7,1%, ceratectomia parcial ("flap" incompleto: 4,3%, presença de dobras estromais (14,3%, desepitelização central (4,3% e crescimento epitelial na interface (4,3%. Já com o CB, foram encontrados: "flap" descentralizado (3%, desepitelização central (5%, dobras estromais (28% e síndrome das Areias de Sahara (6%. Conclusões: O uso inicial de ambos microceratótomos foi relacionado a considerável índice de complicações per e pós-operatórias, não levando necessariamente à perda de visão. Maior conhecimento clínico das alterações ocorridas com o uso destes instrumentos, bem como maior experiência na sua utilização podem diminuir a ocorrência de complicações.Purpose: To describe per- and postoperative complications which occurred with the first use of two automated microkeratomes for the performance of LASIK. Methods: Retrospective study of first surgeries performed with two automated microkeratomes. Seventy

  20. Eficácia do sistema de contenção (automatizado e mecânico no atordoamento de bovinos Effectiveness of the restraining system (automated and mechanical in the cattle stunning

    Directory of Open Access Journals (Sweden)

    William Bertoloni

    2010-08-01

    Full Text Available Um total de 800 bovinos machos (nelore/anelorados, com idade entre 28 e 36 meses, foi atordoado com pistola pneumática, com pressão de operação de 11 a 12bar e haste de penetração de 15.9mm de diâmetro, em sistemas de contenção diferentes (mecânico e atomatizado. O box de contenção mecânico tradicional (2,53x0,88x2,20m não permitiu a contenção da cabeça do animal; no segundo tratamento utilizou-se box de contenção automatizado (2,60x0,85x2,30m, com parede lateral e piso móveis, guilhotina e elevador de cabeça. O box automatizado proporcionou menor número de disparos necessários para o atordoamento (1,0625±0,013 em comparação ao mecânico(1,2025±0,026, (P≤0,0001, reduziu a distância em relação ao ponto ideal no primeiro disparo (1,246±0,918 e 2,357±1,246 e no segundo (3,042±0,141 e 4,016±0,101, (P 0,0001, assim como proporcionou ausência de reflexo respiratório comparativamente ao sistema mecânico (0,0275±0,008, (P≤0,001. O box automatizado apresentou maior bem-estar e maior eficácia na contenção e insensibilização dos bovinosA total of 800 male cattle (Nelore, aged 28-36 months, stunned by pneumatic captive bolt pistol (operating pressure 160-175psi 11-12bar , air consumption (per cycle 1.45ft³ 41L , penetrating shaft diameter 0.625 in 15.9mm in different restrainer systems (mechanical and automated. The traditional mechanical restraint (2.53x0.88x2.20m did not allow the containment of the animal's head, the automated restrainer (2.60x0.85x2.30m allowed adjustable sidewall and restraint and elevating the head. The automatic restrainer provided smaller number of shots required for stunning (1.0625±0.013 compared to mechanical (1.2025±0.026 (P≤0.0001, reduced the distance from the ideal point in the first shot (1.246±0.918 and (2.357±1.246 and second (3.042±0.141 and (4.016±0.101 (P 0.0001, and provided no respiratory reflex compared to the mechanical system (0.0275±0.008, (P≤0.001. The

  1. EPR dosimetric properties of formates

    International Nuclear Information System (INIS)

    As a part of a program to develop an electron paramagnetic resonance (EPR) dosimeter suited for clinical use (doses in the cGy range), polycrystalline samples of lithium formate monohydrate (HCO2Li·H2O), magnesium formate dihydrate (C2H2O4Mg·2H2O), and calcium formate (C2H2O4Ca) have been examined. L-Alanine was included for comparison and reference. Samples were irradiated with 60Co γ-rays and 60-220 kV X-rays. The dosimeter response was assessed using the peak-to-peak amplitude of the first-derivative EPR spectrum. Dose-response curves for the 60Co γ-irradiated samples were constructed, and the dependences of the response on the photon energy, microwave power, and modulation amplitude were studied. Stability of the irradiation products upon storage (signal fading) was also investigated. Lithium formate monohydrate is by far the best candidate of the tested formates, suitable for measuring doses down to approximately 0.1 Gy. Lithium formate monohydrate is more sensitive than alanine by a factor of 5.6-6.8 in the tested photon energy range, it exhibits no zero-dose signal and shows a linear dose response in the dose range from 0.2 to 1000 Gy. Its EPR signal was found unchanged in shape and intensity 1 week after irradiation to 10 Gy. Various less favorable properties rendered the other formates generally unsuitable, although calcium formate exhibits some interesting EPR dosimetric properties

  2. EPR-based material modelling of soils

    Science.gov (United States)

    Faramarzi, Asaad; Alani, Amir M.

    2013-04-01

    In the past few decades, as a result of the rapid developments in computational software and hardware, alternative computer aided pattern recognition approaches have been introduced to modelling many engineering problems, including constitutive modelling of materials. The main idea behind pattern recognition systems is that they learn adaptively from experience and extract various discriminants, each appropriate for its purpose. In this work an approach is presented for developing material models for soils based on evolutionary polynomial regression (EPR). EPR is a recently developed hybrid data mining technique that searches for structured mathematical equations (representing the behaviour of a system) using genetic algorithm and the least squares method. Stress-strain data from triaxial tests are used to train and develop EPR-based material models for soil. The developed models are compared with some of the well-known conventional material models and it is shown that EPR-based models can provide a better prediction for the behaviour of soils. The main benefits of using EPR-based material models are that it provides a unified approach to constitutive modelling of all materials (i.e., all aspects of material behaviour can be implemented within a unified environment of an EPR model); it does not require any arbitrary choice of constitutive (mathematical) models. In EPR-based material models there are no material parameters to be identified. As the model is trained directly from experimental data therefore, EPR-based material models are the shortest route from experimental research (data) to numerical modelling. Another advantage of EPR-based constitutive model is that as more experimental data become available, the quality of the EPR prediction can be improved by learning from the additional data, and therefore, the EPR model can become more effective and robust. The developed EPR-based material models can be incorporated in finite element (FE) analysis.

  3. A simplified apparatus for EPR imaging

    Science.gov (United States)

    Jingchuan, Deng; Kuixiang, Wang; Weiqing, Xu

    1996-06-01

    A simple apparatus for sub-surface electron paramagnetic resonance (EPR) imaging of a cut sample is described. A two-dimensional EPR image corresponding to the electron spin-density distribution of the DPPH test sample has been obtained by using a marginally oscillating self-detecting microwave frequency EPR spectrometer. Higher spatial resolution is obtained by using a deconvolution algorithm and the image processing technique of inverse filtering.

  4. EPR Dosimetry in Irradiated Fingernails

    International Nuclear Information System (INIS)

    The Electron Paramagnetic Resonance (EPR) is being transformed in a complementary tool of biologically-based methods for evaluation of dose after accidental radiation exposure. Many efforts are being carried out in laboratories to evaluate the performance of different materials for its use in EPR doses measurements and for improving the current methods for spectrum analysis and calibration curves determinations. In our country the EPR techniques have been used in different areas with dosimetric (alanine) and non dosimetric purposes. Now we are performing the first studies to obtain properly dose response curves to be used for accidental dose assessments through irradiated fingernails. It is by now well known that the fingernails present two types of signals, a background one (BKS), originated in elastic and inelastic mechanical deformations and the radio induced one (RIS), object of interest (I). In this work we will present some of the previous studies performed to characterize the fingernail samples and we analyse the additive dose method for data obtained employing the technique of the substraction of the spectrum recorded at two different microwave powers in order to reduce the BKS signal. Fingernail samples collected from different donors were treated by soaking in water during 10 min and 5 min drying on paper towel and the BKS signals were studied previously its irradiation. The statistical analysis (R statistics) show a distribution with a Standard Deviation of 24% respects to its media. During these studies we also conserved in freezer for more than 6 months irradiated fingernails that, were periodically measured and the statistical analysis of the peak to peak amplitude show a normal distribution through the Quantile correlation test with a SD 11% respected to its median. (authors)

  5. EPR project construction cost control

    International Nuclear Information System (INIS)

    The EPR project is now managed by EDF in cooperation with the German Utilities. The main engineering activities for this period are related to the preparation of construction project management, deepening of some safety issues, definition of the project technical reference. The EPR project concerns the so-called reference unit, that is an isolated first-off unit, with unit electrical power of about 1500 MW. The construction costs evaluated are those of the nuclear island, the conventional island, site facilities, installation work and the administrative buildings. The EPR project construction cost evaluation method applies to all the equipment installed and commissioned. It requires the availability of a preliminary project detailed enough to identify the bill of quantities. To these quantities are then assigned updated unit prices that are based either on cost bases for similar and recent facilities or taken from request for quotation for similar equipment or result from gains due to contractual conditions benefiting from simplifications in the functional and technical specifications. The input and output data are managed in a model that respects the breakdown on which the evaluation method is based. The structural organization of this method reflects a functional breakdown on the one hand (nuclear island, conventional island, common site elements) and on the other hand a breakdown according to equipment or activity (civil engineering, mechanics, electricity, instrumentation and control). This paper discusses the principle and the method of construction cost evaluation carried out, the cost data base and input and output parameters as well as results and oncoming cost analysis tasks. (author)

  6. EPR of exchange coupled systems

    CERN Document Server

    Bencini, Alessandro

    2012-01-01

    From chemistry to solid state physics to biology, the applications of Electron Paramagnetic Resonance (EPR) are relevant to many areas. This unified treatment is based on the spin Hamiltonian approach and makes extensive use of irreducible tensor techniques to analyze systems in which two or more spins are magnetically coupled. This edition contains a new Introduction by coauthor Dante Gatteschi, a pioneer and scholar of molecular magnetism.The first two chapters review the foundations of exchange interactions, followed by examinations of the spectra of pairs and clusters, relaxation in oligon

  7. EPR techniques for space biodosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Haskell, E.; Hayes, R.; Kenner, G.; Sholom, S.; Chumak, V.

    1996-12-31

    Retrospective dosimetry of tooth enamel has become an increasingly complex and difficult discipline to undertake while still attaining accuracy. The paper provides a review of the major obstacles, advances and pertinent phenomenon associated with low level retrospective dosimetry of human tooth enamel. Also covered is the many sources of error in EPR dosimetry, their potential solutions, as well as the different analysis and scanning techniques in use with their prospective pros and cons. Prospective directions for new approaches, methods, and instruments are also reviewed.

  8. EPR dosimetry with tooth enamel: A review

    International Nuclear Information System (INIS)

    When tooth enamel is exposed to ionizing radiation, radicals are formed, which can be detected using electron paramagnetic resonance (EPR) techniques. EPR dosimetry using tooth enamel is based on the (presumed) correlation between the intensity or amplitude of some of the radiation-induced signals with the dose absorbed in the enamel. In the present paper a critical review is given of this widely applied dosimetric method. The first part of the paper is fairly fundamental and deals with the main properties of tooth enamel and some of its model systems (e.g., synthetic apatites). Considerable attention is also paid to the numerous radiation-induced and native EPR signals and the radicals responsible for them. The relevant methods for EPR detection, identification and spectrum analyzing are reviewed from a general point of view. Finally, the needs for solid-state modelling and studies of the linearity of the dose response are investigated. The second part is devoted to the practical implementation of EPR dosimetry using enamel. It concerns specific problems of preparation of samples, their irradiation and spectrum acquisition. It also describes how the dosimetric signal intensity and dose can be retrieved from the EPR spectra. Special attention is paid to the energy dependence of the EPR response and to sources of uncertainties. Results of and problems encountered in international intercomparisons and epidemiological studies are also dealt with. In the final section the future of EPR dosimetry with tooth enamel is analyzed.

  9. Overview of LBB implementation for the EPR

    Energy Technology Data Exchange (ETDEWEB)

    Cauquelin, C.

    1997-04-01

    This paper presents an overview of the use of leak-before-break (LBB) analysis for EPR reactors. EPR is an evolutionary Nuclear Island of the 4 loop x 1500 Mwe class currently in the design phase. Application of LBB to the main coolant lines and resulting design impacts are summarized. Background information on LBB analysis in France and Germany is also presented.

  10. EPR meeting international safety standards with margin

    International Nuclear Information System (INIS)

    The EPR provides technology that offers a solution to the market's need for safe, economic power. The EPR was originally developed through a joint effort between Framatome ANP and Siemens by incorporating the best technological features from the French and German nuclear reactor fleets into a cost-competitive product capable of international licensing. As such, the EPR is a global product with commercial units currently being built in Finland at the Olkiluoto site, and planned for France, at the Flamanville site. Framatome ANP has recently proposed four EPR units to China in response to a request for vendor bids. In addition, Framatome ANP has announced their intent to pursue design certification in with the United States Nuclear Regulatory Commission (NRC). This paper discusses how EPR's innovative safety philosophy ensures compliance with international safety standards for advanced light-water reactors (ALWRs). (author)

  11. EPR Dosimetry - Present and Future

    International Nuclear Information System (INIS)

    In the past, IAEA has played a central role in stipulating research and development in EPR high-dose standardisation as well as in coordinating and organising international dose intercomparison programs, within the Member States of the United Nations from the mid-seventies till today. The future tasks of EPR dosimetry seem to tend towards different subjects such as bio markers, biological radiation effects, post-accident dose reconstruction in the environment, and retrospective human dosimetry. The latter may be considered a promising tool for epidemiology on the way to re-define radiation risk of man for chronicle radiation exposures, based on e.g. South Ural civil population and radiation workers. There are on-going international activities in the field of standardising high-level dosimetry by the American Standards on Testing and Materials (Astm), and by the International Organisation of Standards (ISO). The International Commission on Radiation Units and Measurements (ICRU) is considering the establishment of relevant recommendations concerning industrial radiation processing, but also human dose reconstruction. (Author)

  12. EPR Dosimetry - Present and Future

    Energy Technology Data Exchange (ETDEWEB)

    Regulla, D.F. [GSF - National Research Centre for Environment and Health, Institute of Radiation Protection, 85764 Neuherberg (Germany)

    1999-07-01

    In the past, IAEA has played a central role in stipulating research and development in EPR high-dose standardisation as well as in coordinating and organising international dose intercomparison programs, within the Member States of the United Nations from the mid-seventies till today. The future tasks of EPR dosimetry seem to tend towards different subjects such as bio markers, biological radiation effects, post-accident dose reconstruction in the environment, and retrospective human dosimetry. The latter may be considered a promising tool for epidemiology on the way to re-define radiation risk of man for chronicle radiation exposures, based on e.g. South Ural civil population and radiation workers. There are on-going international activities in the field of standardising high-level dosimetry by the American Standards on Testing and Materials (Astm), and by the International Organisation of Standards (ISO). The International Commission on Radiation Units and Measurements (ICRU) is considering the establishment of relevant recommendations concerning industrial radiation processing, but also human dose reconstruction. (Author)

  13. EPR dosimetry - present and future

    International Nuclear Information System (INIS)

    In the past, IAEA has played a central role in stipulating research and development in EPR high-dose standardisation as well as co-ordinating and organising international dose intercomparison programs, within the Member States of the United Nations from the mid-seventies till today. The future tasks of EPR dosimetry seem to tend towards different subjects such as biomarkers, biological radiation effects, post-accident dose reconstruction in the environment, and retrospective human dosimetry. The latter may be considered a promising tool for epidemiology on the way to re-define radiation risk of man for chronicle radiation exposures, based on e.g. South Ural civil population and radiation workers. There are on-going international activities in the field of standardising high-level dosimetry by the American Standards on Testing and Materials (ASTM), and the International Organisation of Standards (ISO) as well as those of the International Commission on Radiation Units and Measurements (ICRU) considering the establishment of relevant recommendations concerning industrial radiation processing, but also human dose reconstruction. (author)

  14. Sistema de Información para la Cirugía Neonatal

    OpenAIRE

    Trinchet Soler, Rafael M

    1992-01-01

    Se diseñó un sistema de información para la cirugía del recién nacido. Para ello se confeccionó una planilla de recolección de datos primarios con una serie de variables, las cuales se justifican por su importancia en la especialidad. Para el procesamiento de la información se hizo un sistema automatizado, que, partiendo de los datos primarios y con el uso de codificadores confeccionados al efecto, da respuesta a las diferentes necesidades de información de la cirugía neonatal. Se hace una ex...

  15. Desarrollo de un prototipo simulador del tracto gastrointestinal mediante reactores químicos automatizados

    OpenAIRE

    Rivas Montoya, Ernesto

    2014-01-01

    El prototipo descrito en esta Tesis Doctoral se emplea para realizar la simulación in vitro del tracto gastrointestinal. Esta simulación se lleva a cabo en las tres fases que se describen a continuación: simulación de estómago, simulación de duodeno y absorción intestinal. Fase 1: Simulación de estómago. El estómago se simula en un biorreactor de tanque agitado dotado de los siguientes elementos: -Camisa de refrigeración/calefacción con agua para estabilización de temperatura, cuyo o...

  16. National debate about the EPR

    International Nuclear Information System (INIS)

    With the perspective of a debate in autumn 2005 about the construction of a European Pressurized reactor (EPR) at Flamanville (Manche, France), a collective book of actors is under preparation under the care of the French national commission of public debate. As actor of this debate, the French society of nuclear energy (SFEN) gives its contribution to this book in the form of general presentation text summarizing its position with respect to the project. The main topics presented are: the need of a renewal of part of the French nuclear park, the exploitation of a preliminary model in French conditions, the maintenance of the capacities of the French nuclear industry and of the know-how of its teams, the supply of electric power to France for about 60 years, and the demonstration of the French authority in the nuclear domain. (J.S.)

  17. Time-resolved pulsed EPR: microwave and optical detection

    Energy Technology Data Exchange (ETDEWEB)

    Trifunac, A.D.; Smith, J.P.

    1981-01-01

    Time-resolved pulsed EPR spectrometers are described. EPR spectra, kinetic profiles, and relaxation studies are used to illustrate some capabilities of the pulsed EPR experiment. Optical detection of time-resolved EPR spectra of radical ion pairs is used to study radical-ion recombination kinetics, recombination pathways, and the structure of radical anions and cations. 17 figures.

  18. Time-resolved pulsed EPR: microwave and optical detection

    International Nuclear Information System (INIS)

    Time-resolved pulsed EPR spectrometers are described. EPR spectra, kinetic profiles, and relaxation studies are used to illustrate some capabilities of the pulsed EPR experiment. Optical detection of time-resolved EPR spectra of radical ion pairs is used to study radical-ion recombination kinetics, recombination pathways, and the structure of radical anions and cations. 17 figures

  19. Nitrosyl hemoglobins: EPR above 80 K

    International Nuclear Information System (INIS)

    The EPR spectra of nitrosyl hemoglobin and myoglobin in different conditions (native, denatured and lyophilized), as well as of hematin-NO were obtained in the temperature range of 80 K-280 K. There is a substantial and reversible.decrease of the areas of the EPR spectra of all the hemoglobin samples above 150 K. The interpretation of the results implies the existence of two conformational states in thermal equilibrium only one of which is EPR detectable. Thermodynamical parameters are determined for the hexa and penta-coordinated cases. (author). 25 refs, 3 figs

  20. Nitrosyl hemoglobins: EPR above 80 K

    Energy Technology Data Exchange (ETDEWEB)

    Wajnberg, E.; Bemski, G.; El-Jaick, L.J.; Alves, O.C.

    1995-03-01

    The EPR spectra of nitrosyl hemoglobin and myoglobin in different conditions (native, denatured and lyophilized), as well as of hematin-NO were obtained in the temperature range of 80 K-280 K. There is a substantial and reversible.decrease of the areas of the EPR spectra of all the hemoglobin samples above 150 K. The interpretation of the results implies the existence of two conformational states in thermal equilibrium only one of which is EPR detectable. Thermodynamical parameters are determined for the hexa and penta-coordinated cases. (author). 25 refs, 3 figs.

  1. Método para avaliação do Risco Potencial no âmbito dos Laboratórios Oficiais – Método ARP-LAB / Evaluation Method of Potential Risk under the Official Laboratories: EPR-LAB Method

    Directory of Open Access Journals (Sweden)

    Elizabeth Valverde Macedo

    2015-08-01

    Full Text Available O homem encontra-se exposto a inúmeros produtos tecnológicos, e dentre eles os medicamentos, que geram riscos cada vez mais próximos do imponderável. Duas áreas, com ampla inclusão em vários campos do conhecimento, permeiam o ambiente dos laboratórios envolvidos no monitoramento da qualidade destes produtos. Estas são a metrologia e o risco. O objetivo deste trabalho foi elaborar um Método para Avaliação do Risco Potencial dos laboratórios onde são realizados ensaios em medicamentos (Método ARP-LAB, minimizando assim os resultados com confiabilidade analítica duvidosa. A metodologia utilizada foi baseada no Modelo de Avaliação de Risco Potencial. A referência técnica foi a RDC 11/12 – ANVISA/MS que, após análise crítica, resultou na elaboração de Indicadores de Controle do Risco (ICR que foram planificados no software Excel®. Como resultado, o Método ARP-LAB apresentou 167 ICR que, apesar do grande número de indicadores, mostrou-se bastante útil, aplicável e de fácil utilização ao ambiente laboratorial. Através dele é possível identificar as categorias das causas associadas ao desvio de cada ICR. ----------------------------------------------------------------------------------------------- Humans are exposed to numerous technological products, among them are drugs with increasingly varied risks. Two areas of investigation permeate the environment of laboratories involved in monitoring drug quality. These are metrology and risk. The objective of this study was to elaborate an Evaluation Method of Potential Risk (EPR-LAB Method for drug testing laboratories, minimizing analytical results with questionable reliability. The methodology used was based on the Model of Potential Risk Evaluation. The technical reference was the RDC 11/12 - ANVISA / MS. After critical analysis this study resulted in the development of Risk Control Indicators (RCI that were planned in the Excel software. The EPR-LAB Method developed

  2. Event based simulation of an EPR-B experiment by local hidden variables: epr-simple and epr-clocked

    OpenAIRE

    Gill, Richard D.

    2015-01-01

    In this note, I analyse the data generated by M. Fodje's simulation programs "epr-simple" and "epr-clocked" using appropriate modified Bell-CHSH type inequalities: the Larsson detection loophole adjusted CHSH, and the Larsson-Gill coincidence loophole adjusted CHSH. The experimental efficiencies turn out to be approximately eta = 81% and gamma = 55% respectively, and the observed value of CHSH is (of course) well within the adjusted bounds.

  3. Simulación y control de procesos automatizados con PLCs OMRON y LabVIEW

    OpenAIRE

    Owono Marti, Daniel

    2011-01-01

    Con los nuevos grados instaurados por el nuevo plan universitario, hemos creado unas prácticas de automatización industrial gestionadas con los autómatas de OMRON que la facultad acaba de adquirir. Estos PLCs permiten trabajar con nuevas técnicas de programación y, además tienen incorporado más módulos que permite un aprendizaje más amplio sobre la materia. Para ello, he realizado unas prácticas diseñadas bajo el programa de LabVIEW, con el propósito de simular unas plantas ...

  4. Aplicación de inteligencia artificial en sistemas automatizados de producción

    OpenAIRE

    Llata García, José Ramón; González Sarabia, Esther; Fernández Pérez, Dámaso; Arce Hernando, Jesús Antonio; Pérez Oria, Juan María

    2000-01-01

    “Soy un gigante tan gigante que puedo grabar una rosa en la uña de un niño recién nacido”. Para solucionar el problema el personaje de García Lorca puede emplear diferentes métodos o múltiples paradigmas, como haría un sistema de inteligencia artificial. La inteligencia artificial es “simplemente” la transferencia de la inteligencia a las máquinas, es decir que el computador haga cosas inteligentes. Sin embargo la inteligencia humana es una función tan compleja que los científicos están solo ...

  5. EPR study of some irradiated food enzymes

    International Nuclear Information System (INIS)

    The EPR spectra of three types of amylases (microbial and fungal α-amylase E.C. 3.2.1.1; gluco-amylase E.C. 3.2.1.3) and one type of pectinase irradiated with gamma-rays and 7 MeV electrons are presented and discussed. For all enzymes, a positive correlation (r = 0.991 to 0.994) between the EPR signal amplitude and absorbed dose has been observed, while, between EPR spectra amplitudes and enzyme in vitro activity, in terms of enzymatic activity a negative correlation (r = -0.987 to -0.995), has been noticed. These facts recommend that enzyme damage during irradiation can be monitored by means of the free radicals detected by EPR spectroscopy. (author)

  6. New loophole for the EPR paradox

    OpenAIRE

    Feldmann, Michel

    1999-01-01

    We exhibit a classical model free from any paradox which exactly simulates the spin EPR test. We conclude that Bell's inequality violation is a strictly classical phenomenon, contrary to a general belief.

  7. EPR dosimetry of human dental enamel

    International Nuclear Information System (INIS)

    Dental enamel was the object of dosimetry with the use of electron paramagnetic resonance (EPR); the teeth extracted for medical causes in the residents of Kiev, the Kiev and Zhitomir regions were analyzed. New data on radiation defects in dental enamel are presented and problems of EPR dosimetry in humans analyzed, approaches to the development and improvement of the method of retrospective assessment of the dose load with this method are outlined

  8. Applications of EPR in radiation research

    CERN Document Server

    Lund, Anders

    2014-01-01

    Applications of EPR in Radiation Research is a multi-author contributed volume presented in eight themes: I. Elementary radiation processes (in situ and low temperature radiolysis, quantum solids); II: Solid state radiation chemistry (crystalline, amorphous and heterogeneous systems); III: Biochemistry, biophysics and biology applications (radicals in biomaterials, spin trapping, free-radical-induced DNA damage); IV: Materials science (polymeric and electronic materials, materials for treatment of nuclear waste, irradiated food); V: Radiation metrology (EPR-dosimetry, retrospective and medical

  9. EPR Dosimetry: an update and prospective studies

    International Nuclear Information System (INIS)

    Electron Paramagnetic Resonance (EPR) technique is useful to quantify the paramagnetic species in any matrix. The unpaired electrons present in paramagnetic materials have non - zero spin value, have an associated spin magnetic moment. When such a system is subjected to an external magnetic field, electronic Zeeman splitting of ground level state occurs. On application of suitable stimulant microwave energy, the electrons flip between the Zeeman levels of ground state, result in resonant absorption of the microwave energy. The intensity of resonant absorption signal is proportional to the concentration of the unpaired electrons in the irradiated material, could lead to possible use of such materials in EPR dosimetric applications. New materials were investigated for EPR dosimetry, wherein the radiation induced paramagnetic species retains the radiation signatures, lead to idea on radiation dose. Few of the materials have been identified as prospective EPR dosimeters. The radiation induced radical in Li2CO3 powder material being paramagnetic in nature (signals at g = 2.0036 and at g 2.0006) and radical concentration varying as a function of irradiation dose, led to its identification for possible use in EPR dosimetric applications. Besides, during the neutron irradiations, the reaction 6Li (n,α) 3H, led to the yield of radicals many folds higher compared to that of gamma irradiation. Thus, the commonly available Li2CO3 material has been assessed for the EPR dosimetric response in gamma and neutron environments. EPR investigation of Li2C2O4, Na2C2O4 mixtures was carried out to measure the radiation dose from γ photons and thermal neutrons in a mixed radiation field. A single line spectrum of CO2- radical at g = 2.0045 ± 0.0005 was found on gamma and neutron irradiations. Of all the mixture combinations, the 2:1 mixture was found more sensitive for gamma / thermal neutrons. Intensity of CO2- radical signal was found linear from 6 Gy - 11 kGy for gamma and 40 - 1500

  10. Automated control of electronic equipment in intelligent buildings; Control automatizado de equipo electrico en edificios inteligentes

    Energy Technology Data Exchange (ETDEWEB)

    Gutierrez Vera, Jorge [Electrica Integral, S. A. de C. V., Mexico, D. F. (Mexico)

    1993-12-31

    esta reservada a la nacion a traves de Comision Federal de Electricidad (CFE). La cual es un organismo descentralizado del Gobierno Federal y por ende, sujeta entre muchas otras a la Ley de Presupuesto, Contabilidad y Gasto Publico. Quienes conocemos CFE sabemos de la gran dificultad, siempre creciente, de allegarse recursos para financiar sus obras de infraestructura, entre las que podemos citar: centrales electricas, subestaciones, lineas de transmision y redes de distribucion. Por lo anterior, los programas de ahorro y conservacion de la energia representan para el sector electrico nacional la posibilidad de diferir las inversiones requeridas para garantizar la oferta de energia. Por otra parte, a los usuarios del servicio publico de energia, el instituir dentro de sus politicas operativas programas de ahorro y conservacion de la energia, indudablemente les redundara en beneficios economicos y se mejorara el indice de kWh/Unidad de producto terminado. Finalmente, en un pais como el nuestro en donde el 66% de la energia generada por el sector electrico nacional proviene de centrales termoelectricas que usan para su operacion combustibles fosiles, la implementacion generalizada de programas de ahorro de energia disminuira la necesidad de generar kWh, y en consecuencia, la emision de contaminantes agresivos al medio ambiente tales como oxidos de nitrogeno y de azufre, bioxido de carbono y particulas suspendidas.

  11. Desarrollo de una plataforma de gestión de un laboratorio automatizado

    OpenAIRE

    González Muñoz, Sergio

    2015-01-01

    El presente TFG está enmarcado en el contexto de la biología sintética (más concretamente en la automatización de protocolos) y representa una parte de los avances en este sector. Se trata de una plataforma de gestión de laboratorios autónomos. El resultado tecnológico servirá para ayudar al operador a coordinar las máquinas disponibles en un laboratorio a la hora de ejecutar un experimento basado en un protocolo de biología sintética. En la actualidad los experimentos biológicos tienen una t...

  12. Shared experience in 13 local Danish EPR projects: the Danish EPR Observatory.

    Science.gov (United States)

    Nøhr, C; Kristensen, M; Andersen, S K; Vingtoft, S; Lippert, S; Berstein, K; Bruun-Rasmussen, M

    2001-01-01

    In 1996 a national strategy for the development of electronic patient records (EPR) for the Danish hospitals and primary care was launched. An element in the strategy was to support a number of regional EPR development projects. The EPR-Observatory has in the two recent years collected data from the regional projects, dealing with the expectations in four areas: 1) Impact on organisational issues, 2) Benefits of EPR, 3) Integration of EPR with other information systems and 4) security aspects of EPR. Among the observations an increasing teamwork and im-proved knowledge about the patient was found. What was expected, but not found, was resistance to EPR, as a result of changes in skills and power. The most obvious benefits are increased data accessibility and improved decision ma-king. The most considerable disadvantage is an enormous growth in discontent with the systems performance and the fact, that all the projects are delayed. Many different types of integration solutions are chosen, because of a lack of a common model for integration. Generally the projects find, that EPJ yields increased security, but logistical problems arise in having the systems running 24 hours 7 days a week. Economical benefits cannot be documented. This relates to the fact, that the regional projects are stand-alone projects. The ongoing growth in discontent with the EPR-systems and the fact, that all the projects are delayed must be subject to further exploration. PMID:11604822

  13. Selfcalibrated alanine/EPR dosimeters. A new generation of solid state/EPR dosimeters

    International Nuclear Information System (INIS)

    Alanine/EPR dosimeters are well established as secondary, reference dosimeters for high-energy radiation. However, there are various sources of uncertainty in the evaluation of absorbed dose. This arises primarily from the necessity to calibrate each EPR spectrometer and each batch of dosimeters before their use. In order to overcome this disadvantage, a new generation alanine/EPR dosimeter has been developed, and its possibilities as a radiation detector are reported. Principally, it is a mixture of alanine, some quantity of EPR active substance, and a binding material. The EPR active substance, acting as an internal EPR standard, is chosen to have EPR parameters which are independent of the irradiation dose. The simultaneous recording of the spectra of both the sample and the standard under the same experimental conditions and the estimation of the ratio Ialanine/IMn as a function of the absorbed dose strongly reduces the uncertainties. The response of these dosimeters for 60Co γ-radiation exhibits excellent linearity and reproducibility in the range of absorbed dose, 102 - 5 x 104 Gy. (author)

  14. EPR (Electronic Patient Record Laboratory - Simulated Environment to Learn about a Hospital EPR System

    Directory of Open Access Journals (Sweden)

    Kazuko Yamamoto

    2011-03-01

    Full Text Available The “Electronic Patient Record (EPR Laboratory” is a computer based self-learning system developed for students to acquire practical skills and knowledge required to deal with EPRs. The system is designed to supplement conventional lectures on health information systems given as part of our undergraduate curriculum. Using the Laboratory, the students may learn not only operations of EPR systems but also the subjects connected with patient information handling, including privacy, security and health information ethics. The EPR Laboratory is composed of an eLearing system and an EPR system. The learning materials are arranged in units in the eLearning system, and in each unit, the student learns the materials and the EPR operations through practice. Tests are given at each end of unit, and if a student failed a test, the system shows which questions were answered incorrectly and indicates which parts of the unit he/she should review. For this purpose, we introduced a structure to the learning materials based on an information model. In this paper, the overview of the system, the simulated environment to learn patient flow, information flow and hospital workflow, fundamental EPR operations, and structured learning materials for the test and review cycle are described.

  15. EPR deployment shifting into high gear

    International Nuclear Information System (INIS)

    EPR is a large advanced evolutionary PWR resulting from extensive French-German cooperation. After a decade of design which associated the power plant vendors, Framatome and Siemens KWU (whose nuclear activities have since been merged to form Framatome ANP, now an AREVA and Siemens company), Electricite de France (EDF) and the major German utilities as well as the safety authorities from both countries, EPR has now begun its industrial life. A first unit is under construction in Finland, a second unit has been decided by EDF in France. Chinese perspectives and North America markets evolutions are contributing to the growing feeling of a nuclear renaissance. EPR projects are on track to meet the needs. (author)

  16. Computational and instrumental methods in EPR

    CERN Document Server

    Bender, Christopher J

    2006-01-01

    Computational and Instrumental Methods in EPR Prof. Bender, Fordham University Prof. Lawrence J. Berliner, University of Denver Electron magnetic resonance has been greatly facilitated by the introduction of advances in instrumentation and better computational tools, such as the increasingly widespread use of the density matrix formalism. This volume is devoted to both instrumentation and computation aspects of EPR, while addressing applications such as spin relaxation time measurements, the measurement of hyperfine interaction parameters, and the recovery of Mn(II) spin Hamiltonian parameters via spectral simulation. Key features: Microwave Amplitude Modulation Technique to Measure Spin-Lattice (T1) and Spin-Spin (T2) Relaxation Times Improvement in the Measurement of Spin-Lattice Relaxation Time in Electron Paramagnetic Resonance Quantitative Measurement of Magnetic Hyperfine Parameters and the Physical Organic Chemistry of Supramolecular Systems New Methods of Simulation of Mn(II) EPR Spectra: Single Cryst...

  17. EPR study of free radicals in bread

    Science.gov (United States)

    Yordanov, Nicola D.; Mladenova, Ralitsa

    2004-05-01

    The features of the recorded EPR spectra of paramagnetic species formed in bread and rusk are reported. The appearance of free radicals in them is only connected with their thermal treatment since the starting materials (flour and grains) exhibit very weak EPR signal. The obtained EPR spectra are complex and indicate that: (i) the relative number of paramagnetic species depends on the temperature and treating time of the raw product; (ii) the g-values are strongly temperature dependent with a tendency to coincide at t≥220 °C. Because of the relatively low (150-220 °C) temperature of thermal treatment, the studied free radicals can be assumed to appear in the course of the browning (Maillard) reaction and not to the carbonization of the material.

  18. Can EPR non-locality be geometrical?

    Energy Technology Data Exchange (ETDEWEB)

    Ne`eman, Y. [Tel-Aviv Univ. (Israel). Raymond and Beverly Sackler Faculty of Exact Sciences]|[Univ. of Texas, Austin, TX (United States). Center for Particle Physics; Botero, A. [Texas Univ., Austin, TX (United States)

    1995-10-01

    The presence in Quantum Mechanics of non-local correlations is one of the two fundamentally non-intuitive features of that theory. The non-local correlations themselves fall into two classes: EPR and Geometrical. The non-local characteristics of the geometrical type are well-understood and are not suspected of possibly generating acausal features, such as faster-than-light propagation of information. This has especially become true since the emergence of a geometrical treatment for the relevant gauge theories, i.e. Fiber Bundle geometry, in which the quantum non-localities are seen to correspond to pure homotopy considerations. This aspect is reviewed in section 2. Contrary-wise, from its very conception, the EPR situation was felt to be paradoxical. It has been suggested that the non-local features of EPR might also derive from geometrical considerations, like all other non-local characteristics of QM. In[7], one of the authors was able to point out several plausibility arguments for this thesis, emphasizing in particular similarities between the non-local correlations provided by any gauge field theory and those required by the preservation of the quantum numbers of the original EPR state-vector, throughout its spatially-extended mode. The derivation was, however, somewhat incomplete, especially because of the apparent difference between, on the one hand, the closed spatial loops arising in the analysis of the geometrical non-localities, from Aharonov-Bohm and Berry phases to magnetic monopoles and instantons, and on the other hand, in the EPR case, the open line drawn by the positions of the two moving decay products of the disintegrating particle. In what follows, the authors endeavor to remove this obstacle and show that as in all other QM non-localities, EPR is somehow related to closed loops, almost involving homotopy considerations. They develop this view in section 3.

  19. Study of EPR response of PTFE

    International Nuclear Information System (INIS)

    Full text: The quantification of free radicals in irradiated paramagnetic substances based on Electron Paramagnetic Resonance (EPR) is a useful method for high level dosimetry. Stable Paramagnetic centers formed in polymers irradiated with gamma radiation were studied in the 1990s. Considering that the PTFE effective atomic number is near the human tissue, this material can be interesting for application in quality control in blood, blood components and foodstuffs irradiations. EPR dosimeters based on polytetrafluoroethylene (PTFE) for gamma irradiation in the dose range from 6x102 at 1x105 Gy have been developed and characterized in recent years. This work presents the efforts for characterization of an EPR gamma dosimeter based on commercial PTFE for the dose range between 10 Gy to 1 kGy. The samples were irradiated in a GammaCell irradiator and EPR spectra were recorded using an EMX Bruker spectrometer operating X-band with a standard rectangular cavity at room temperature. The EPR settings were carried out with a microwave frequency of 9.85 GHz; microwave power of 10.11 m W, magnetic field modulation amplitude of 0.5 mT and modulation frequency of 100 kHz. The main parameters studied were EPR signal response as a function of the gamma radiation dose, reproducibility, signal fading and dose rate dependence. The standard deviations obtained in the reproducibility test not exceed 8.5%. The PTFE irradiated samples stored at room temperature conditions presented a signal decay of 12% in the first 45 days after irradiation. (author)

  20. The U.S. EPR: a standardized nuclear power plant

    International Nuclear Information System (INIS)

    The U.S. EPR is an evolutionary 1600 MW PWR design that represents the U.S. element of AREVA-NP's global EPR fleet. Simply stated, AREVA-NP's business strategy is to launch a global fleet of standardized EPRs. The EPR's standardisation process addresses the following topics: 1) standardized utility requirements, 2) standardized licensing, 3) commercial standardization, and 4) life-cycle standardization. AREVA-NP's approach for EPR design standardization is achieved via a hierarchical configuration management process that is applied both globally and regionally. A key element of this standardization process is the EPR Configuration Management Board (ECMB) whose purpose is twofold: manage the configuration of the EPR generic design and ensure the orderly identification and transfer of lessons learned among global EPR projects. The project management process established by ECMB consists of 3 major elements. First, the U.S. EPR Steering Committee that was established to oversee U.S. EPR project execution in the context of AREVA-NP's other EPR projects. Secondly, the U.S. EPR Standardization Committee whose primary role is to maintain U.S. EPR standardization as well as global standardization as directed by ECMB. Thirdly, the U.S. EPR Change Control Review that will determine the relevancy of issues or any proposed change. UniStar Nuclear is a joint venture between Constellation Generation and AREVA-NP that provides a flexible business model for new nuclear generation. Standardized operation of U.S. EPR units is a fundamental tenet of UniStar Nuclear that will complete the U.S. EPR approach for life-cycle commitment to standardization

  1. EPR properties of intact and deproteinated dentin

    International Nuclear Information System (INIS)

    The effect of sample preparation on dentin electron paramagnetic resonance (EPR) spectra was investigated. The analysis was performed on dentin samples prepared by pure mechanical treatment or by an alkaline deproteination method. It was observed that (1) mechanical treatment induces both stable and transient signals, depending on the specific mechanical operation applied; and (2) sodium hydroxide deproteination removes the native signal, but at the same time introduces new confounding signals in the EPR spectrum. Also, it increases the radiation sensitivity of dentin. These findings suggest that attention must be paid to dentin sample preparation. (authors)

  2. Barium dithionate as an EPR dosemeter.

    Science.gov (United States)

    Baran, M P; Bugay, O A; Kolesnik, S P; Maksimenko, V M; Teslenko, V V; Petrenko, T L; Desrosiers, M F

    2006-01-01

    Electron paramagnetic resonance (EPR) dosimetry is growing in popularity and this success has encouraged the search for other dosimetric materials. Previous studies of gamma-irradiated barium dithionate (BaS(2)O(6) x 2H(2)O) have shown promise for its use as a radiation dosemeter. This work studies in greater detail several essential attributes of the system. Special attention has been directed to the study of EPR response dependences on microwave power, irradiation temperature, minimum detectable dose and post-irradiation stability. PMID:16565205

  3. Mast-sipping in EPR trademark plants

    International Nuclear Information System (INIS)

    For more than 20 years, AREVA applies and develops different sipping techniques to identify fuel assemblies with leaking fuel rods. For the EPR trademark reactors a Mast Sipping System with newest developments will be implemented considering radiation protection and latest standards requirements. The innovative EPR trademark Sipping System differs from previous systems in many ways. One of the main innovations is that all the necessary processes of the Sipping system have been fully digitized. Second, several ALARA design modifications have been implemented to meet the current radiation protection requirements. An additional implementable multilingual assistance program facilitates the handling of the system and helps to prevent incorrect operation. (orig.)

  4. TL and EPR dating: some applications

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, S. [Institute of Physics, University of Sao Paulo, Sao Paulo (Brazil)

    2006-07-01

    The intensity of thermoluminescence light emitted by a crystal is a function of radiation dose. The number of defects or of radicals in a crystal or organic substances is also a function of radiation dose. Since such defects or radicals present EPR signals, the EPR intensity is also a function of radiation dose. These facts are basis for radiation dosimetry and can be applied in dating of archaeological potteries or other materials, as well as in dating geological substances such as sediments, caves speleothemes, animal teeth and bones. Recent investigation on sensitized quartz based dosimeters and dating calcite covering ancient wall painting to find early settlers in Brazil will be presented. (Author)

  5. TL and EPR dating: some applications

    International Nuclear Information System (INIS)

    The intensity of thermoluminescence light emitted by a crystal is a function of radiation dose. The number of defects or of radicals in a crystal or organic substances is also a function of radiation dose. Since such defects or radicals present EPR signals, the EPR intensity is also a function of radiation dose. These facts are basis for radiation dosimetry and can be applied in dating of archaeological potteries or other materials, as well as in dating geological substances such as sediments, caves speleothemes, animal teeth and bones. Recent investigation on sensitized quartz based dosimeters and dating calcite covering ancient wall painting to find early settlers in Brazil will be presented. (Author)

  6. Identification of irradiated crab using EPR

    Energy Technology Data Exchange (ETDEWEB)

    Maghraby, A. [Radiation Dosimetry Department, National Institute for Standards (NIS), Ministry of Scientific Research, Haram, 12211- Giza, P.O. Box: 136 (Egypt)]. E-mail: maghrabism@yahoo.com

    2007-02-15

    EPR spectroscopy is a fast and powerful technique for the identification of irradiated food. Crab exoskeleton was divided into six parts: dactyl, cheliped, carapace, apron, swimming legs, and walking legs. Samples of the exoskeleton were prepared and irradiated to Cs-137 gamma radiation in the range (1.156-5.365 kGy). EPR spectra of unirradiated as well as irradiated samples were recorded and analyzed. Response to gamma radiation was plotted for each part of the exoskeleton, dactyl was found to be the most sensitive part, followed by the apron (38%), cheliped (37%), walking legs (30%), swimming legs (24%), and carapace (21%) relative to the dactyl response.

  7. Identification of irradiated crab using EPR

    International Nuclear Information System (INIS)

    EPR spectroscopy is a fast and powerful technique for the identification of irradiated food. Crab exoskeleton was divided into six parts: dactyl, cheliped, carapace, apron, swimming legs, and walking legs. Samples of the exoskeleton were prepared and irradiated to Cs-137 gamma radiation in the range (1.156-5.365 kGy). EPR spectra of unirradiated as well as irradiated samples were recorded and analyzed. Response to gamma radiation was plotted for each part of the exoskeleton, dactyl was found to be the most sensitive part, followed by the apron (38%), cheliped (37%), walking legs (30%), swimming legs (24%), and carapace (21%) relative to the dactyl response

  8. Oak Ridge EPR and TNS studies

    International Nuclear Information System (INIS)

    This ORNL Study has resulted in an evaluated Reference Design that does satisfy the technical objectives set out for a tokamak Experimental Power Reactor. Because of the large size and cost and poor extrapolation of this design to a demonstration reactor, a reconsideration of the basic physics and range of technical objectives has been undertaken. This has led to an intermediate step and new design, TNS-The Next Step after TFTR, having a higher benefit/cost than EPR. The TNS experiment, now in the early design phases, is based on a smaller size and considerably higher power output than the EPR design, and extrapolates to an economically viable fusion reactor

  9. Mast-sipping in EPR trademark plants

    Energy Technology Data Exchange (ETDEWEB)

    Langenberger, Jan [AREVA NP GmbH, Erlangen (Germany). Fuel Service; Schienbein, Marcel; Geier, Roland [AREVA NP GmbH, Erlangen (Germany). Radiochemical Lab.

    2010-05-15

    For more than 20 years, AREVA applies and develops different sipping techniques to identify fuel assemblies with leaking fuel rods. For the EPR trademark reactors a Mast Sipping System with newest developments will be implemented considering radiation protection and latest standards requirements. The innovative EPR trademark Sipping System differs from previous systems in many ways. One of the main innovations is that all the necessary processes of the Sipping system have been fully digitized. Second, several ALARA design modifications have been implemented to meet the current radiation protection requirements. An additional implementable multilingual assistance program facilitates the handling of the system and helps to prevent incorrect operation. (orig.)

  10. Comparative growth of trichoderma strains in different nutritional sources, using bioscreen c automated system Crescimento de linhagens de Trichoderma em diferentes fontes nutricionais, empregando o sistema automatizado Bioscreen C.

    Directory of Open Access Journals (Sweden)

    Bianca Caroline Rossi-Rodrigues

    2009-06-01

    Full Text Available Trichoderma is one of the fungi genera that produce important metabolites for industry. The growth of these organisms is a consequence of the nutritional sources used as also of the physical conditions employed to cultivate them. In this work, the automated Bioscreen C system was used to evaluate the influence of different nutritional sources on the growth of Trichoderma strains (T. hamatum, T. harzianum, T. viride, and T. longibrachiatum isolated from the soil in the Juréia-Itatins Ecological Station (JIES, São Paulo State - Brazil.The cultures were grown in liquid culture media containing different carbon- (2%; w/v and nitrogen (1%; w/v sources at 28ºC, pH 6.5, and agitated at 150 rpm for 72 h. The results showed, as expected, that glucose is superior to sucrose as a growth-stimulating carbon source in the Trichoderma strains studied, while yeast extract and tryptone were good growth-stimulating nitrogen sources in the cultivation of T. hamatum and T. harzianum.Trichoderma é um dos gêneros de fungos produtores de metabólitos de interesse industrial. O crescimento destes organismos é conseqüência das fontes nutricionais utilizadas, juntamente com as condições físicas de cultivo. Neste trabalho, o sistema automatizado Bioscreen C foi utilizado para avaliar a influência de diferentes fontes nutricionais sobre o crescimento de linhagens de Trichoderma (T. hamatum, T. harzianum, T. viride e T. longibrachiatum isoladas do solo da Estação Ecológica da Juréia-Itatins (JIES, São Paulo - Brasil. Os cultivos foram feitos em meios líquidos de cultura contendo diferentes fontes de carbono (2%; w / v e nitrogênio (1%; w / v a 28ºC, pH 6,5 e agitados a 150 rpm durante 72 h. Os resultados mostraram, conforme esperado, que a glicose é melhor do que a sacarose como fonte de carbono indutora de crescimento das linhagens de Trichoderma testadas, enquanto que, o extrato de leveduras e a triptona foram boas fontes de nitrogênio indutoras de

  11. Electron Paramagnetic Resonance Imaging: 2. Radiofrequency FT-EPR Imaging

    Indian Academy of Sciences (India)

    2016-08-01

    In this part we shall outline the challenges one faces whiledeveloping time-domain radiofrequency (RF) EPR imagingspectrometer for in vivo studies. Time-domain or FT-EPR isquite a different animal compared to the CW modality. Theevolution of FT-EPR instrumentation at the National CancerInstitute, NIH, USA and representative examples of applicationin cancer research are outlined in this article.

  12. Sistema para la adquisición, almacenamiento y análisis de corrientes iónicas transmembrana

    OpenAIRE

    Ureña López, Juan

    1987-01-01

    El objetivo general del presente trabajo ha sido el diseño e implementación de un sistema automatizado para el control del potencial de membrana y la adquisición, almacenamiento, representación en pantalla y análisis de corrientes iónicas generadas en la membrana de células mantenidas en cultivo. El sistema, construido sobre un ordenador personal, es de una gran rapidez y versatilidad y permite su adaptación para el registro y medida en tiempo real de cualquier fenómeno celular que pueda conv...

  13. MDEP Common Position No EPR-01 - Common positions on the EPR instrumentation and controls design

    International Nuclear Information System (INIS)

    The purpose of the EPR Working Group (EPRWG) of the Multinational Design Evaluation Program (MDEP) is to identify common positions among the regulators reviewing the EPR Instrumentation and Controls (I and C) Systems in order to: 1. Promote understanding of each country 's regulatory decisions and basis for the decisions, 2. Enhance communication among the members and with external stakeholders, 3. Identify areas where harmonization and convergence of regulations, standards, and guidance can be achieved or improved, and 4. Supports standardization of new reactor designs. Since January 2008, the EPR I and C Technical Expert Subgroup (TESG) members met five times to exchange information regarding their country 's review of the EPR I and C design. The EPR I and C TESG consists of regulators from China, Canada, Finland, France, the United Kingdom, and the United States. The information exchange includes presentation of each country 's review status and technical issues, sharing of guidance documents, and sharing of regulatory decision documents. The TESG focused on the following four core areas of the EPR I and C design: 1. I and C System Independence (particularly for data communications), 2. Level of Defense and Diversity (back-up systems), 3. Qualification/quality of digital platforms, 4. Categorization/classification of systems and functions. As meetings were conducted, some areas were emphasized more depending on the significance of the issues for each country. During the TESG interactions, it became apparent that there were aspects of the EPR design where the countries had common agreement. On November 2, 2009, three of the subgroup countries, France, Finland and the United Kingdom, issued a joint regulatory position on the EPR I and C design as result of the 'Groupe Permanent' meeting in France. This statement of common positions expands upon that joint regulatory position

  14. EPR dosimetry in chemically treated fingernails

    Energy Technology Data Exchange (ETDEWEB)

    Romanyukha, A. [Uniformed Services University of the Health Sciences, Bethesda, MD 20814 (United States)], E-mail: aromanyukha@usuhs.mil; Trompier, F. [Institut de Radioprotection et de Surete Nucleaire, BP 17, F-92265 Fontenay-aux-roses (France); LeBlanc, B. [Uniformed Services University of the Health Sciences, Bethesda, MD 20814 (United States); Calas, C.; Clairand, I. [Institut de Radioprotection et de Surete Nucleaire, BP 17, F-92265 Fontenay-aux-roses (France); Mitchell, C.A.; Smirniotopoulos, James G. [Uniformed Services University of the Health Sciences, Bethesda, MD 20814 (United States); Swartz, H.M. [Dartmouth Medical School, Hanover, NH 03755 (United States)

    2007-07-15

    By using EPR measurements of radiation-induced radicals it is possible to utilize human fingernails to estimate radiation dose after-the-fact. One of the potentially limiting factors in this approach is the presence of artifacts due to mechanically induced EPR signals (MIS) caused by mechanical stress during the collection and preparation of the samples and the so-called background (non-radiation) signal (BKS). The MIS and BKS have spectral parameters (shape, g-factor and linewidth) that overlap with the radiation-induced signal (RIS) and therefore, if not taken into account properly, could result in a considerable overestimation of the dose. We have investigated the use of different treatments of fingernails with chemical reagents to reduce the MIS and BKS. The most promising chemical treatment (20 min with 0.1 M dithiothreitol aqueous solution) reduced the contribution of MIS and BKS to the total intensity of EPR signal of irradiated fingernails by a factor of 10. This makes it potentially feasible to measure doses as low as 1 Gy almost immediately after irradiation. However, the chemical treatment reduces the intensity of the RIS and modifies dose dependence. This can be compensated by use of an appropriate calibration curve for assessment of dose. On the basis of obtained results it appears feasible to develop a field-deployable protocol that could use EPR measurements of samples of fingernails to assist in the triage of individuals with potential exposure to clinically significant doses of radiation.

  15. The EPR detection of radiation treated foodstuffs

    International Nuclear Information System (INIS)

    The short paper by a Polish study group describes the results of the use of Electron Paramagnetic Resonance (EPR) Spectroscopy in the detection of irradiation to food. Pultry, fresh-water fish and sea fish as well as various fruits and yellow boletus are dealt with in some detail. (VHE)

  16. EPR-spectroscopic properties of chicory

    International Nuclear Information System (INIS)

    By means of electron paramagnetic resonance-spectroscopy the containing of free radicals in rhizomes, leaves and stems of chicory is studied. According to spectral parameters of EPR signal it is defined that the quantity of free radicals containing in rhizomes, leaves and stems of chicory depends on its growth place and ecological condition of environment.

  17. EPR spin trapping of protein radicals

    DEFF Research Database (Denmark)

    Davies, Michael Jonathan; Hawkins, Clare L

    2004-01-01

    Electron paramagnetic resonance (EPR) spin trapping was originally developed to aid the detection of low-molecular-mass radicals formed in chemical systems. It has subsequently found widespread use in biology and medicine for the direct detection of radical species formed during oxidative stress...... selected examples of radical formation on proteins....

  18. Monitoring enzymatic ATP hydrolysis by EPR spectroscopy

    OpenAIRE

    Hacker, Stephan M.; Hintze, Christian; Marx, Andreas; Drescher, Malte

    2014-01-01

    An adenosine triphosphate (ATP) analogue modified with two nitroxide radicals is developed and employed to study its enzymatic hydrolysis by electron paramagnetic resonance spectroscopy. For this application, we demonstrate that EPR holds the potential to complement fluorogenic substrate analogues in monitoring enzymatic activity.

  19. Assessment of performance parameters for EPR dosimetry with tooth enamel

    International Nuclear Information System (INIS)

    In the framework of a comparison between three laboratories, electron paramagnetic resonance (EPR) signal-to-dose response curves were measured for sets of 30 tooth enamel samples and the variance of EPR measurements in dependence on absorbed dose was evaluated, in nine combinations of laboratory of sample preparation and EPR evaluation, respectively. As a test for benchmarking of EPR evaluation, the parameters 'critical dose' and 'limit of detection' were proposed as performance parameters following definitions from chemical-metrology, and a model function was suggested for analytical formulation of the dependence of the variance of EPR measurement on absorbed dose. First estimates of limits of detection by weighted and unweighted fitting resulted in the range 101-552 and 67-561 mGy, respectively, and were generally larger with weighted than with unweighted fitting. Indication was found for the influence of methodology of sample preparation and applied EPR measurement parameters on performance of EPR dosimetry with tooth enamel

  20. EPR-based material modelling of soils considering volume changes

    Science.gov (United States)

    Faramarzi, Asaad; Javadi, Akbar A.; Alani, Amir M.

    2012-11-01

    In this paper an approach is presented for developing material models for soils based on evolutionary polynomial regression (EPR), taking into account its volumetric behaviour. EPR is a recently developed hybrid data mining technique that searches for structured mathematical equations (representing the behaviour of a system) using genetic algorithm and the least squares method. Stress-strain data from triaxial test are used to train and develop EPR-based material models for soil. The developed models are compared with some of the well known conventional material models. In particular, the capability of the developed EPR models in predicting volume change behaviour of soils is illustrated. It is also shown that the developed EPR-based material models can be incorporated in finite element (FE) analysis. Two geotechnical examples are presented to verify the developed EPR-based FE model (EPR-FEM). The results of the EPR-FEM are compared with those of a standard FEM where conventional constitutive models are used to describe the material behaviour. The results show that EPR-FEM can be successfully employed to analyse geotechnical engineering problems. The advantages of the proposed EPR models are highlighted.

  1. Holographic EPR Pairs, Wormholes and Radiation

    CERN Document Server

    Chernicoff, Mariano; Pedraza, Juan F

    2013-01-01

    As evidence for the ER=EPR conjecture, it has recently been observed that the string that is holographically dual to an entangled quark-antiquark pair separating with (asymptotically) uniform acceleration has a wormhole on its worldsheet. We point out that a two-sided horizon and a wormhole actually appear for much more generic quark-antiquark trajectories, which is consistent with the fact that the members of an EPR pair need not be permanently out of causal contact. The feature that determines whether the causal structure of the string worldsheet is trivial or not turns out to be the emission of gluonic radiation by the dual quark and antiquark. In the strongly-coupled gauge theory, it is only when radiation is emitted that one obtains an unambiguous separation of the pair into entangled subsystems, and this is what is reflected on the gravity side by the existence of the worldsheet horizon.

  2. EPR Steering inequalities with Communication Assistance

    Science.gov (United States)

    Nagy, Sándor; Vértesi, Tamás

    2016-01-01

    In this paper, we investigate the communication cost of reproducing Einstein-Podolsky-Rosen (EPR) steering correlations arising from bipartite quantum systems. We characterize the set of bipartite quantum states which admits a local hidden state model augmented with c bits of classical communication from an untrusted party (Alice) to a trusted party (Bob). In case of one bit of information (c = 1), we show that this set has a nontrivial intersection with the sets admitting a local hidden state and a local hidden variables model for projective measurements. On the other hand, we find that an infinite amount of classical communication is required from an untrusted Alice to a trusted Bob to simulate the EPR steering correlations produced by a two-qubit maximally entangled state. It is conjectured that a state-of-the-art quantum experiment would be able to falsify two bits of communication this way. PMID:26880376

  3. EPR becomes reality at Finland's Olkiluoto 3

    International Nuclear Information System (INIS)

    The EPR is a third-generation pressurized water reactor (PWR). Its development was started in 1992 by Framatome and Siemens within a Franco-German partnership. Since 2001 this work has been continued by Framatome ANP, which was formed when the two companies merged their nuclear businesses. The French company AREVA, world market leader in nuclear technology, holds a 66% share in Framatome ANP, with Siemens owning 34%. From the very start, development of the EPR was focused on improving plant safety and economics even further. The new reactor development was jointly financed together with the leading power utilities of both countries. The first steps towards realization of an EPR nuclear power plant were taken at Olkiluoto, Finland in 2004, consisting of initial preparation of the construction site. By mid-February 2005 the local municipality - Eurajoki - had issued a construction permit, and the Finnish Government a construction license pursuant to the Finnish Nuclear Energy Act. This had been preceded by a preliminary safety assessment prepared by the Finnish Radiation and Nuclear Safety Authority (STUK) for the Finnish Ministry of Trade and Industry in which STUK verified that it did not see any safety-related issues opposing issuance of the nuclear construction license. STUK emphasized that the evolutionary design of the EPR had been further improved by AREVA compared to the previous product lines. Concreting work began this spring and the unit will start commercial operation in 2009. Construction of an EPR has also been given the political go-ahead in France. According to the utility Electricite de France (EDF) the new reactor will be built as a forerunner of a later series at the site of Flamanville in Normandy. Construction is scheduled to begin in 2007. An EPR nuclear power plant has a rated electric capacity of around 1600 MW, depending on specific site conditions. Being the product of intense bilateral cooperation the EPR combines the technological

  4. Self-testing through EPR-steering

    Science.gov (United States)

    Šupić, Ivan; Hoban, Matty J.

    2016-07-01

    The verification of quantum devices is an important aspect of quantum information, especially with the emergence of more advanced experimental implementations of quantum computation and secure communication. Within this, the theory of device-independent robust self-testing via Bell tests has reached a level of maturity now that many quantum states and measurements can be verified without direct access to the quantum systems: interaction with the devices is solely classical. However, the requirements for this robust level of verification are daunting and require high levels of experimental accuracy. In this paper we discuss the possibility of self-testing where we only have direct access to one part of the quantum device. This motivates the study of self-testing via EPR-steering, an intermediate form of entanglement verification between full state tomography and Bell tests. Quantum non-locality implies EPR-steering so results in the former can apply in the latter, but we ask what advantages may be gleaned from the latter over the former given that one can do partial state tomography? We show that in the case of self-testing a maximally entangled two-qubit state, or ebit, EPR-steering allows for simpler analysis and better error tolerance than in the case of full device-independence. On the other hand, this improvement is only a constant improvement and (up to constants) is the best one can hope for. Finally, we indicate that the main advantage in self-testing based on EPR-steering could be in the case of self-testing multi-partite quantum states and measurements. For example, it may be easier to establish a tensor product structure for a particular party’s Hilbert space even if we do not have access to their part of the global quantum system.

  5. EPR TOOTH DOSIMETRY OF SNTS AREA INHABITANTS

    OpenAIRE

    Sholom, Sergey; Desrosiers, Marc; Bouville, André; Luckyanov, Nicholas; Chumak, Vadim; Simon, Steven L.

    2007-01-01

    The determination of external dose to teeth of inhabitants of settlements near the Semipalatinsk Nuclear Test Site (SNTS) was conducted using the EPR dosimetry technique to assess radiation doses associated with exposure to radioactive fallout from the test site. In this study, tooth doses have been reconstructed for 103 persons with all studied teeth having been formed before the first nuclear test in 1949. Doses above those received from natural background radiation, termed “accident doses”...

  6. Validação laboratorial de um método automatizado de dosagem da atividade de adenosina desaminase em líquido pleural e em líquido cefalorraquidiano Laboratorial validation of an automated assay for the determination of adenosine deaminase activity in pleural fluid and cerebrospinal fluid

    Directory of Open Access Journals (Sweden)

    Márcia Cristina Feres

    2008-12-01

    Full Text Available OBJETIVO: A incidência global de tuberculose reforça a necessidade de melhores ensaios para o diagnóstico desta doença, principalmente da tuberculose extrapulmonar. O objetivo do trabalho foi validar o desempenho de um método automatizado para a determinação da atividade de adenosina desaminase (ADA no líquido pleural (LP e no líquido cefalorraquidiano (LCR, comparando-o com um método convencional (Giusti modificado. MÉTODOS: Selecionaram-se 134 amostras da rotina laboratorial: 94 de LP e 40 de LCR. Foram realizadas as determinações da atividade de ADA através dos dois métodos. Calculou-se a precisão inter- e intra-ensaios, análise de regressão linear, testes de concordância simples e médias das diferenças. RESULTADOS: Os coeficientes de correlação para as amostras de LP e LCR foram, respectivamente, 0,96 e 0,95. A precisão interensaio foi determinada pela média de 21 amostras replicadas em ensaios diferentes para 3 níveis de atividade: baixa, média e alta. Os coeficientes de variação em porcentagem (%CV foram, respectivamente, 5,9, 8,1 e 5,8 para amostras de LP; e 21,9, 18,6 e 13,8 para amostras de LCR, respectivamente. A precisão intra-ensaio em %CV foi, respectivamente, 1,3 e 11,7% para amostras de LP e LCR. A concordância entre os dois métodos em amostras de LP e LCR foi, respectivamente, 96,8% e 100%, considerando-se como valores de referência para o diagnóstico de TB 40 U/L (convencional e 30 U/L (automatizado em amostras de LP, e 9 U/L em amostras de LCR para os dois métodos. CONCLUSÕES: Os resultados validaram o método automatizado de determinação da atividade de ADA para o uso em amostras de LP e LCR como alternativa ao método convencional.OBJECTIVE: The incidence of tuberculosis worldwide has emphasized the need for better assays designed to diagnose the disease, principally the extrapulmonary form. The objective of the present study was to validate the performance of an automated method for the

  7. Factors influencing EPR dosimetry in fingernails

    International Nuclear Information System (INIS)

    The technique based on the detection of ionizing radiation induced radicals by EPR in tooth enamel is an established method for the dosimetry of exposed persons in radiological emergencies. Dosimetry based on EPR spectral analysis of fingernail clippings, currently under development, has the practical advantage of the easier sample collection. A limiting factor is that overlapping the radiation induced signal (RIS), fingernails have shown the presence of two mechanically induced signals, called MIS1 and MIS2, due to elastic and plastic deformation respectively, at the time of fingernails cutting. With a water treatment, MIS1 is eliminated while MIS2 is considerably reduced. The calibration curves needed for radiation accident dosimetry should have 'universal' characteristics, ie. Represent the variability that can be found in different individuals. Early studies were directed to the analysis of factors affecting the development of such universal calibration curves. The peak to peak amplitude of the signal before and after the water treatment as well as the effect of size and number of clippings were studied. Furthermore, the interpersonal and intrapersonal variability were analyzed. Taking into account these previous studies, the optimal conditions for measurement were determined and EPR spectra of samples irradiated at different doses were used for the developing of dose-response curves. This paper presents the analysis of the results.(authors)

  8. EPR: the electricians' point of view

    International Nuclear Information System (INIS)

    This article gives the French and German electricians point of view about the technical solutions retained in the European Pressurized water Reactor (EPR) project for the choice of systems, components and safety standards according to their respective experience. Standardisation, availability, unit power and cycle cost are the main factors that determine the cost of the project. The new requests of French and German safety authorities have determined the fundamental choices for safety systems, nuclear auxiliary systems, external aggression protections and prevention of severe accidents in agreement with the solutions retained for existing reactors. The main differences in the conception of the existing N4 french reactor and the Konvoi German reactor are listed as an example and compared to the solutions retained for the common EPR project. The standardisation policy adopted for the EPR project will lead in 1997 to the redaction of a preliminary safety and functional specificities report necessary to start the authorization procedure for a first realisation. (J.S.). 1 tab

  9. Tetrabromidocuprates(II)-Synthesis, Structure and EPR.

    Science.gov (United States)

    Zabel, André; Winter, Alette; Kelling, Alexandra; Schilde, Uwe; Strauch, Peter

    2016-01-01

    Metal-containing ionic liquids (ILs) are of interest for a variety of technical applications, e.g., particle synthesis and materials with magnetic or thermochromic properties. In this paper we report the synthesis of, and two structures for, some new tetrabromidocuprates(II) with several "onium" cations in comparison to the results of electron paramagnetic resonance (EPR) spectroscopic analyses. The sterically demanding cations were used to separate the paramagnetic Cu(II) ions for EPR measurements. The EPR hyperfine structure in the spectra of these new compounds is not resolved, due to the line broadening resulting from magnetic exchange between the still-incomplete separated paramagnetic Cu(II) centres. For the majority of compounds, the principal g values (g‖ and g⊥) of the tensors could be determined and information on the structural changes in the [CuBr₄](2-) anions can be obtained. The complexes have high potential, e.g., as ionic liquids, as precursors for the synthesis of copper bromide particles, as catalytically active or paramagnetic ionic liquids. PMID:27104522

  10. Tetrabromidocuprates(II—Synthesis, Structure and EPR

    Directory of Open Access Journals (Sweden)

    André Zabel

    2016-04-01

    Full Text Available Metal-containing ionic liquids (ILs are of interest for a variety of technical applications, e.g., particle synthesis and materials with magnetic or thermochromic properties. In this paper we report the synthesis of, and two structures for, some new tetrabromidocuprates(II with several “onium” cations in comparison to the results of electron paramagnetic resonance (EPR spectroscopic analyses. The sterically demanding cations were used to separate the paramagnetic Cu(II ions for EPR measurements. The EPR hyperfine structure in the spectra of these new compounds is not resolved, due to the line broadening resulting from magnetic exchange between the still-incomplete separated paramagnetic Cu(II centres. For the majority of compounds, the principal g values (g‖ and g⊥ of the tensors could be determined and information on the structural changes in the [CuBr4]2− anions can be obtained. The complexes have high potential, e.g., as ionic liquids, as precursors for the synthesis of copper bromide particles, as catalytically active or paramagnetic ionic liquids.

  11. Active or passive systems? The EPR approach

    International Nuclear Information System (INIS)

    In attempting to review how EPR is contemplated to meet requirements applicable to future nuclear power plants, the authors indicate where they see the markets and the corresponding unit sizes for the EPR which is a generic key factor for competitiveness. There are no reason in industrialized countries, other than USA (where the investment and amortizing practices under control by Public Utility Commission are quite particular), not to build future plants in the 1000 to 1500 MWe range. Standardization, which has been actively applied all along the French program and for the Konvoi plants, does not prevent evolution and allows to concentrate large engineering effort in smooth realization of plants and achieve actual construction and commissioning without significant delays. In order to contribute to public trust renewal, a next generation of power reactors should be fundamentally less likely to incur serious accidents. To reach this goal the best of passive and active systems must be considered without forgetting that the most important source of knowledge is construction and operating experience. Criteria to assess passive systems investigated for possible implementation in the EPR, such as simplicity of design, impact on plant operation, safety and cost, are discussed. Examples of the principal passive systems investigated are described and reasons why they have been dropped after screening through the criteria are given. (author). 11 figs

  12. Instrumento para o gerenciamento de riscos ambientais

    Directory of Open Access Journals (Sweden)

    Thaiza Clemente Couto Bissacot

    2016-01-01

    Full Text Available RESUMO: Embora existam normas e metodologias padronizadas para a análise de riscos ambientais dentro de uma organização, os mecanismos e/ou instrumentos disponíveis estão sujeitos à subjetividade, não são automatizados, não estabelecem critérios técnicos e, de maneira geral, não apresentam mecanismos de priorização para a tomada de decisão. Com base nas lacunas observadas, a presente nota técnica apresenta as premissas de um Instrumento de Gestão para a Identificação e o Gerenciamento de Riscos Ambientais (IGIGRA. O dashboard consolidado pelo IGIGRA permitirá a visualização consolidada dos riscos ambientais do empreendimento, proporcionando comparações entre diferentes operações e períodos de avaliação, fornecendo base técnica para a priorização de ações e alocação de recursos para o controle dos riscos dentro da organização.

  13. Retrospective individual dosimetry using EPR of tooth enamel

    International Nuclear Information System (INIS)

    The results of joint investigations (in the framework of ECP-10 program) aimed on the improvement of the sensitivity and accuracy of the procedure of dose measurement using tooth enamel EPR spectroscopy are presented. It is shown, what the sensitivity of method may be increased using special physical-chemical procedure of the enamel samples treatment, which leads to the reducing of EPR signal of organic components in enamel. Tooth diseases may have an effect on radiation sensitivity of enamel. On the basis of statistical analysis of the results of more then 2000 tooth enamel samples measurements it was shown, what tooth enamel EPR spectroscopy gives opportunity to register contribution into total dose, which is caused by natural environmental radiation and by radioactive contamination. EPR response of enamel to ultraviolet exposure is investigated and possible influences to EPR dosimetry is discussed. The correction factors for EPR dosimetry in real radiation fields are estimated

  14. Some ideas on the EPR; Elements de reflexion sur l'EPR

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    Facing the debate and controversial between partisans and opponents of the European Pressurized Reactor construction, the SFP energy Group aims to offer some reflexions. In this framework the following topics are discussed: the french nuclear park and its replacement, the energy costs, the nuclear reactors profitability, the generation IV reactors. The paper examines then the EPR technology and its cost to conclude on the advantage of an EPR construction, in the case of an energy policy based on the nuclear. This last point seems to be the real challenge of the problem. (A.L.B.)

  15. A web-based database for EPR centers in semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Umeda, T. [Graduate School of Library, Information, and Media Studies, Research Center for Knowledge Communities, University of Tsukuba, Tsukuba 305-8550 (Japan)]. E-mail: umeda@slis.tsukuba.ac.jp; Hagiwara, S. [Graduate School of Library, Information, and Media Studies, Research Center for Knowledge Communities, University of Tsukuba, Tsukuba 305-8550 (Japan); Katagiri, M. [Graduate School of Library, Information, and Media Studies, Research Center for Knowledge Communities, University of Tsukuba, Tsukuba 305-8550 (Japan); Mizuochi, N. [Graduate School of Library, Information, and Media Studies, Research Center for Knowledge Communities, University of Tsukuba, Tsukuba 305-8550 (Japan); Isoya, J. [Graduate School of Library, Information, and Media Studies, Research Center for Knowledge Communities, University of Tsukuba, Tsukuba 305-8550 (Japan)

    2006-04-01

    We develop a web-based database system for electron paramagnetic resonance (EPR) centers in semiconductors. This database is available to anyone at http://www.kc.tsukuba.ac.jp/div-media/epr/. It currently has more than 300 records of the spin-Hamiltonian parameters for major known EPR centers. One can upload own new records to the database or can use simulation tools powered by EPR-NMR(C). Here, we describe the features and objectives of this database, and mention some future plans.

  16. Use of the Frank sequence in pulsed EPR.

    Science.gov (United States)

    Tseitlin, Mark; Quine, Richard W; Eaton, Sandra S; Eaton, Gareth R; Halpern, Howard J; Ardenkjaer-Larsen, J-H

    2011-04-01

    The Frank polyphase sequence has been applied to pulsed EPR of triarylmethyl radicals at 25 6 MHz (9.1 mT magnetic field), using 256 phase pulses. In EPR, as in NMR, use of a Frank sequence of phase steps permits pulsed FID signal acquisition with very low power microwave/RF pulses (ca. 1.5 mW in the application reported here) relative to standard pulsed EPR. A 0.2 mM aqueous solution of a triarylmethyl radical was studied using a 16 mm diameter cross-loop resonator to isolate the EPR signal detection system from the incident pulses. PMID:21371924

  17. EPR study on gamma-irradiated fruits dehydrated via osmosis

    Energy Technology Data Exchange (ETDEWEB)

    Yordanov, N.D. [Laboratory EPR, Institute of Catalysis, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria)]. E-mail: ndyepr@bas.bg; Aleksieva, K. [Laboratory EPR, Institute of Catalysis, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria)

    2007-06-15

    The shape and time stability of the electron paramagnetic resonance (EPR) spectra of non- and {gamma}-irradiated papaya, melon, cherry and fig samples dehydrated via osmosis are reported. It is shown that non-irradiated samples are generally EPR silent whereas {gamma}-irradiated exhibit 'sugar-like' EPR spectra. The recorded EPR spectra are monitored for a period of 7 months after irradiation (stored at low humidity and in the dark). The results suggest longer period of unambiguous identification of the radiation processing of osmose dehydrated fruits. Therefore, the Protocol EN 13708,2001 issued by CEN is fully applicable for the studied fruit samples.

  18. Identification of gamma-irradiated fruit juices by EPR spectroscopy

    International Nuclear Information System (INIS)

    The results of electron paramagnetic resonance (EPR) study on commercially available juices from various fruits and different fruit contents: 25%, 40%, 50%, and 100%, homemade juices, nectars and concentrated fruit syrups, before and after gamma-irradiation are reported. In order to remove water from non- and irradiated samples all juices and nectars were filtered; the solid residue was washed with alcohol and dried at room temperature. Only concentrated fruit syrups were dried for 60 min at 40 °C in a standard laboratory oven. All samples under study show a singlet EPR line with g=2.0025 before irradiation with exception of concentrated fruit syrups, which are EPR silent. Irradiation of juice samples gives rise to complex EPR spectra which gradually transferred to “cellulose-like” EPR spectrum from 25% to 100% fruit content. Concentrated fruit syrups show typical “sugar-like“ spectra due to added saccharides. All EPR spectra are characteristic and can prove radiation treatment. The fading kinetics of radiation-induced EPR signals were studied for a period of 60 days after irradiation. - Highlights: • The EPR analysis of juices, nectars and syrups proves that the sample has been irradiated. • Two sample preparation procedures were used. • The stability of the radiation induced EPR signals was studied over 2 months. • Application of European standards can be extended for irradiated juices and syrups

  19. The EPR nuclear reactor: a dangerous and useless project

    International Nuclear Information System (INIS)

    After a presentation of the EPR (European Pressurized Reactor) concept and a discussion of the associated risks for the French nuclear industry, the contributions analyse the role the EPRs would have within the next 30 years, discuss the lifetimes of nuclear plants and new reactor types, discuss the impact of nuclear policies on the greenhouse effect by 2050 at the national and world scale, discuss the EPR economic aspect (the KWh cost), and discuss the social implications of a choice between the EPR and renewable energies

  20. Integración de los estándares UML y WfMC para el modelado de workflows

    OpenAIRE

    Acosta, Edgardo; Uva, Marcelo; Grando, Adela; Riesco, Daniel Eduardo

    2003-01-01

    Un proceso de negocio es un conjunto de tareas lógicamente relacionadas que se ejecutan para obtener un cierto resultado de negocio. Un proceso de negocio incluye tanto recursos humanos como materiales. Los procesos de negocio pueden ser controlados y administrados por un sistema basado en software, proceso de negocio automatizado de esta manera se denomina workflow. Esta automatización resulta en una importante potenciación de las virtudes de dicho proceso. La WfMC (Workflow Management Co...

  1. Locations of radical species in black pepper seeds investigated by CW EPR and 9 GHz EPR imaging

    Science.gov (United States)

    Nakagawa, Kouichi; Epel, Boris

    2014-10-01

    In this study, noninvasive 9 GHz electron paramagnetic resonance (EPR)-imaging and continuous wave (CW) EPR were used to investigate the locations of paramagnetic species in black pepper seeds without further irradiation. First, lithium phthalocyanine (LiPC) phantom was used to examine 9 GHz EPR imaging capabilities. The 9 GHz EPR-imager easily resolved the LiPC samples at a distance of ∼2 mm. Then, commercially available black pepper seeds were measured. We observed signatures from three different radical species, which were assigned to stable organic radicals, Fe3+, and Mn2+ complexes. In addition, no EPR spectral change in the seed was observed after it was submerged in distilled H2O for 1 h. The EPR and spectral-spatial EPR imaging results suggested that the three paramagnetic species were mostly located at the seed surface. Fewer radicals were found inside the seed. We demonstrated that the CW EPR and 9 GHz EPR imaging were useful for the determination of the spatial distribution of paramagnetic species in various seeds.

  2. Public debate on the EPR reactor; Debat public sur le reacteur EPR

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-10-15

    In the framework of the new EPR European Pressurized Reactor implementation in France, the public asked the first Ministry on the protection of nuclear matters, transports and installations against the terrorism and the spiteful actions. This document provides information on the subject and shows the safety of the new reactor. (A.L.B.)

  3. Avaliação da microestrutura e propriedades mecânicas de metais de solda obtidos por processos de soldagem manual e automatizado utilizado na soldagem de aço API 5L X80 Evaluation of microstructure and mechanical properties of weld metals obtained by manual and automated welding process used in the welding of API 5L X80 steel

    Directory of Open Access Journals (Sweden)

    Siderley Fernandes Albuquerque

    2011-12-01

    Full Text Available O objetivo do trabalho foi avaliar as características da zona termicamente afetada (ZTA e a microestrutura e propriedades mecânicas de metais de solda de juntas soldadas do aço API 5L X80, obtidos para quatro diferentes procedimentos de soldagem utilizando processos manuais e automatizados. Para isto, chapas do referido aço foram soldadas por processo manual ao Arco Elétrico com Eletrodo Revestido (SMAW, utilizando 473 e 673 K como temperaturas de interpasses e o eletrodo celulósico AWS E8010-G como consumível; por processo ao Arco Elétrico com Arame Tubular (FCAW robotizado, utilizando o arame AWS E71T- 1C como metal de adição e argônio com 25%CO2 como gás de proteção; por processo a Arco Elétrico com Eletrodo de Tungstênio (GTAW mecanizado na raiz da solda, usando o arame ER70S-3 e argônio como gás de proteção. As análises microestruturais foram relacionadas com os resultados de ensaios de impacto Charpy nos metais de solda e com os perfis de microdureza Vickers ao longo da junta soldada. Os resultados indicaram maiores percentuais de Ferrita Acicular e maiores valores de resistência ao impacto nos metais de solda e uma menor extensão e granulometria da ZTA, associado ao procedimento de soldagem utilizando processo automatizado com maior velocidade de soldagem.The objective of this work was to evaluate the heat affected zone characteristics and weld metals microstructure and mechanical properties of API 5L X80 steel welded joints, obtained for four different welding procedures using manual and automated processes. For this, plates of this steel were welded by manual Shielded Metal Arc Welding (SMAW process with interpasses temperatures of 473 e 673 K, and using AWS E8010-G electrode as filler metals; robotized Flux Cored Arc Welding (FCAW process, using AWS E71T-1C wire and Ar25%CO2 as consumable and mechanized Gas Tungsten Arc Welding (GTAW process, for the root pass using AWS ER70S-3 and Ar as consumable .The

  4. EPR: what has it taught us

    International Nuclear Information System (INIS)

    This symposium commemorating the fiftieth anniversary of the paper of Einstein, Podolsky, and Rosen is a fitting place to review what that work and its sequels have taught us. Prima facie, the EPR paper appears to have been exceedingly counter-productive for the following reasons: (1) The work was quickly rebutted by Bohr, and this rebuttal was apparently accepted by most workers in the field. (2) Scientists who adopted the position advocated by Bohr have produced, in the intervening fifty years, a marvelous body of useful theory, whereas those following the course suggested by EPR have produced nothing of any certified practical value. (3) It has been shown by Bell that the conclusion reached by EPR is incompatible with their assumptions. Chemists and physicists have recently begun to examine the behavior of quantum mechanical systems that are very small, yet large enough to influence their environment in ways that appreciably modify their own behavior, vis-a-vis the behavior they would have if isolated. Because these systems are neither small enough to be treated as isolated (or as residing in a classically described environment) between preparation and detection, nor large enough to be treated classically, they do not conform to the format demanded by the Copenhagen interpretation. Indeed, the behavior of these systems depends on ontological considerations that were irrelevant in the situations covered by the Copenhagen interpretation, and that were systematically ignored in that interpretation. Scientists now face the task of enlarging the scope of quantum theory to cover these new situations, and comparing the empirical consequences of various ontological assumptions. 17 refs

  5. CFD modeling of the EPR primary circuit

    International Nuclear Information System (INIS)

    Highlights: • A RANS CFD computation of almost all of the EPR reactor primary circuit is demonstrated. • Comparison with experimental data of the obtained results is carried out. • Hydraulic decoupling between main vessel elements in normal operation is pointed out. • Promising results are found out with regards to nuclear plants’ safety demonstration. - Abstract: The present paper deals with the feasibility of a RANS CFD computation of almost all of the primary circuit of a EPR PWR reactor. The developed model includes the vessel, the core, the steam generators and the associated piping. The flow in the primary circuit is studied under normal operations with balanced flow rates between loops. The k–ε realizable model is retained for the turbulence modeling, and standard wall functions are used as wall treatment. The constructed grid contains about 181,000,000 elements, mainly hexahedrons. The computation is performed with the commercial CFD code STAR-CD, and despite the relatively large amount of cells, such kind of computation is fully accessible at an industrial scale with today available computational resources. A comparison with experimental data of the obtained results is carried out. The simulation results in the vessel are confronted to measurements issued from JULIETTE and ROMEO mock-ups, representative of the EPR lower and upper internals respectively. Regarding the steam generators, a benchmark with the dedicated code GENEPI is also performed. An overall good agreement with the reference data is underlined. The potential up-and-downstream effects of the different modeled components brought interesting knowledge, especially with regards to safety issues. These encouraging results allow in testing, in a near future, this model in other configurations such as unbalanced operation or accidental transients

  6. EPR properties of Rindler space-time

    International Nuclear Information System (INIS)

    In a flat region of space that contains a quantum field in its Minkowski ground state, an observer with constant proper acceleration (Rindler observer) will detect a thermal background of particles with a temperature proportional to that observer's acceleration. This result generated great interest in the Minkowski vacuum as expressed in terms of Rindler field states, as is evident by the number of discussions presented at this workshop on this very subject. Adding to the body of observations concerning this effect, this report shows that the Minkowski vacuum for a scalar field, as expressed in terms of Rindler field states, is an EPR state

  7. EPR: a reactor for the next century

    International Nuclear Information System (INIS)

    This paper gives answers to some questions asked by the public opinion about the opportunity of the French-German European Pressurized Reactor (EPR) project. The first aspect is the economical interest of the project taking into account the increasing power demand. The second point is the development of new safety systems which influences the public acceptance of nuclear power, and the standardization of conception and safety rules which increases the competitiveness of the project. Finally, the French-German cooperation has reinforced the fundamental link between electricians, industrialists and safety authorities. (J.S.). 2 figs

  8. EPR study on tomatoes before and after gamma-irradiation

    International Nuclear Information System (INIS)

    The results from the EPR studies on fresh, air-dried and lyophilized tomato samples before and after gamma-irradiation are reported. Before irradiation fresh and air-dried tomatoes exhibit one singlet EPR line characterized with common g-factor of 2.0048±0.0005, whereas freeze-dried tomato does not show any EPR spectrum. After irradiation, a typical 'cellulose-like' triplet EPR spectrum appears in all samples, attributed to cellulose free radicals, generated by gamma-irradiation. It consists of intense central line with g=2.0048±0.0005 and two weak satellite lines separated ca. 3 mT left and right of it. In air-dried and lyophilized tomatoes the 'cellulose-like' EPR spectrum is superimposed by an additional partly resolved carbohydrate spectrum. Fading measurements of the radiation-induced EPR signals indicate that the intensity of the EPR spectra of air-dried and freeze-dried tomato are reduced to about 50% after 50 days, whereas those of fresh irradiated tomatoes kept at 4 oC fade completely in 15 days. The reported results unambiguously show that the presence of two satellite lines in the EPR 'cellulose-like' spectra of tomato samples can be used for identification of radiation processing.

  9. THE RADIATION CROSSLINKING OF EPR/SBR BLEND

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wanxi; L(U) Yingtao; SUN Jiazhen

    1990-01-01

    The radiation crosslinking of EPR/SBR blend has been studied. A relationship between sol fraction and radiation dose for the different weight ratio polymer blends and the method to calculate βb value of EPR/SBR blend system have been established.

  10. EPR investigation of some gamma-irradiated excipients

    Science.gov (United States)

    Aleksieva, Katerina; Yordanov, Nicola D.

    2012-09-01

    The results of electron paramagnetic resonance (EPR) studies on some excipients: lactose, microcrystalline cellulose (avicel), starch, dioxosilane (aerosil), talc and magnesium stearate before and after gamma-irradiation are reported. Before irradiation, all samples are EPR silent except talc. After gamma-irradiation, they show complex spectra except magnesium stearate, which is EPR silent. Studies show the influence of gamma-irradiation on EPR spectra and stability of gamma-induced radicals. Analysis of the EPR spectrum of gamma-irradiated talc shows that this material is radiation insensitive. Only lactose forms stable-free radicals upon gamma sterilization and can be used for identification of radiation processing for a long time period thereafter.

  11. Use of the Frank sequence in pulsed EPR

    DEFF Research Database (Denmark)

    Tseitlin, Mark; Quine, Richard W.; Eaton, Sandra S.;

    2011-01-01

    The Frank polyphase sequence has been applied to pulsed EPR of triarylmethyl radicals at 256MHz (9.1mT magnetic field), using 256 phase pulses. In EPR, as in NMR, use of a Frank sequence of phase steps permits pulsed FID signal acquisition with very low power microwave/RF pulses (ca. 1.5mW in the...... application reported here) relative to standard pulsed EPR. A 0.2mM aqueous solution of a triarylmethyl radical was studied using a 16mm diameter cross-loop resonator to isolate the EPR signal detection system from the incident pulses. Keyword: Correlation spectroscopy,Multi-pulse EPR,Low power pulses...

  12. Desarrollo de una metodología de evaluación de usabilidad de interfaces humano-máquina (IHM) para la mejora del Proceso de toma de decisiones en tareas de supervisión industrial

    OpenAIRE

    Hurtado Cortés, Luini Leonardo

    2013-01-01

    Ésta tesis propone, a partir de los métodos y herramientas para la monitorización y supervisión de procesos industriales automatizados, los fundamentos de la ergonomía cognitiva (Cañas y Waern, 2001) y los conceptos de usabilidad de sistemas interactivos (Benyon, 2013), el desarrollo, aplicación y validación de una metodología para la evaluación de la usabilidad de interfaces de sistemas de supervisión industrial. Inicialmente, se ha planteado una revisión de conceptos sobre cómo se conci...

  13. PROCEDIMIENTO JERÁRQUICO BASADO EN OPTIMIZACIÓN Y SIMULACIÓN PARA LA GESTIÓN DE VEHÍCULOS EN SISTEMAS AUTOMATIZADOS DE MANUFACTURA

    Directory of Open Access Journals (Sweden)

    Jairo Rafael Montoya Torres

    Full Text Available This paper focuses on the analysis of transport strategies in Automated Material Handling Systems (AMHS for automated manufacturing systems. The problem studied is inspired from an application found in the semiconductor industry. A difference against previous work is that our approach takes into account the unified nature load transport moves that, in the past, have limited the practical usefulness of the results provided. In a unified AMHS, vehicles can travel along the whole network path to deliver loads directly from one machine to another machine (tool-to-tool delivery without passing by intermediate storage. Since the number of vehicles is limited, an intelligent strategy has to be implemented in order to distribute them so as to optimally satisfy transport requests during the production horizon. The problem is addressed by means of a hierarchical tactical planning-operational control approach using simulation-optimization. At the tactical, vehicles are distributed on the network path by integer linear programming. The tactical solution is then implemented on a detailed simulation model of the factory in order to analyze factory dynamics. Experimental results show the improvement of performance indexes that can be achieved by implementing the proponed procedure.

  14. Diseño y cálculo de un transelevador para un almacén automatizado de carrocerías

    OpenAIRE

    Mayor González, Rubén

    2012-01-01

    Este proyecto introduce en el campo de los almacenes automáticos operados mediante transelevador. En concreto se analiza el almacén que se va a construir y poner en marcha en una fábrica de automóviles, con dos pasillos. En el proyecto de analizan las necesidades de tiempos de ciclos y se realiza un estudio mecánico de las partes más relevantes de un transelevador como pueden ser las características básicas de éste en función de las necesidades, potencia de los motores, cálculo de la estructu...

  15. Sistema automatizado para aquisição de dados de umidade relativa do ar Automated system for relative humidity data acquisition

    OpenAIRE

    Késia O. da Silva; Sergio O. Moraes; Jarbas H. de Miranda; Anderson M. Palmieri

    2007-01-01

    Devido à importância do ambiente na produção animal e vegetal e, portanto, controle ambiental adequado, o trabalho propõe como objetivo a construção de um sistema de aquisição automatizada de dados de umidade relativa do ar, utilizando-se de microcontrolador de dimensões reduzidas e de baixo custo. A calibração do sensor de umidade relativa foi realizada em três etapas de simulação desenvolvidas em laboratório: caixas perfuradas, dessecador sem tampa contendo sílica-gel em seu fundo e psicrom...

  16. Systems automated reporting of patient dose in digital radiology; Sistema automatizado para generacion de informes de dosis a paciente en radiologia digital

    Energy Technology Data Exchange (ETDEWEB)

    Collado Chamorro, P.; Sanz Freire, C. J.; Martinez Mirallas, O.; Tejada San Juan, S.; Lopez de Gammarra, M. S.

    2013-07-01

    It has developed a procedure automated reporting of doses to patients in Radiology. This procedure allows to save the time required of the data used to calculate the dose to patients by yields. Also saves the time spent in the transcription of these data for the realization of the necessary calculations. This system has been developed using open source software. The characteristics of the systems of digital radiography for the automation of procedures, in particular the registration of dose should benefit from patient. This procedure is validated and currently in use at our institution. (Author)

  17. Sistema automatizado para aquisição de dados de umidade relativa do ar Automated system for relative humidity data acquisition

    Directory of Open Access Journals (Sweden)

    Késia O. da Silva

    2007-12-01

    Full Text Available Devido à importância do ambiente na produção animal e vegetal e, portanto, controle ambiental adequado, o trabalho propõe como objetivo a construção de um sistema de aquisição automatizada de dados de umidade relativa do ar, utilizando-se de microcontrolador de dimensões reduzidas e de baixo custo. A calibração do sensor de umidade relativa foi realizada em três etapas de simulação desenvolvidas em laboratório: caixas perfuradas, dessecador sem tampa contendo sílica-gel em seu fundo e psicrometria. As etapas de calibração, utilizando situações naturais e artificiais, bem como as metodologias desenvolvidas, apresentaram resultados que permitem concluir que o sistema pode ser utilizado com segurança no monitoramento dessa variável.Due the importance of the environment in animal and crop production and therefore an appropriate environmental control, the main objective of this work is the construction of an automated system for relative humidity data acquisition, using a controller with reduced dimensions and low cost. Calibration was performed under natural and artificial conditions. The methodology showed results that the system can be used for monitoring this environmental factor.

  18. Licensing Experience for EPR Flamanville 3

    International Nuclear Information System (INIS)

    This presentation discusses the three stages of the EPR Flamanville 3 Licensing process: the political decision to build a new nuclear power plant, the authorization decree for nuclear power plant creation/construction license, and the commission and operation license. The operating license process requires the operator to submit the safety analysis report, the general operating rules, a study on waste management, the onsite emergency plan, and an update, as necessary of the decommissioning plan and the environmental impact assessment. The presentation follows with a discussion on the licensing of the Flamanville 3 EPR reactor. Flamanville 3 licensing was a longstanding and continuous process taking 18 years for the 3 main steps (1989 to 2007) and resulting in the authorization decree. The presentation describes the safety objectives utilized in the process, the integration of recent operating experience, innovations, and design and manufacturing. It also highlights several examples of modifications that resulted from the technical assessment supporting the authorization decree, including diversification of emergency electrical supply, practical elimination of fuel melt in the fuel pool, and diversification of heat sink and essential service water system. It reviews the contents of the authorization decree. Next, it discusses current on-going activities and milestones related to commissioning and operating license application and notes that current ASN/IRSN review activities are focused on a number of topics, including accident studies, I and C, protection system, internal and external events, detailed design of systems playing a safety role as supporting systems, equipment qualification to accident conditions, radiological consequences, several accident management, probabilistic studies, and several other topics. It explains that a 'focusing' review principle is used to inform the level of review for each topic. This principle is used to choose the SSCs that will

  19. EPR design features to mitigate severe accident challenges

    International Nuclear Information System (INIS)

    The EPR, an evolutionary pressurized water reactor (PWR), is a 4300-4500 MWth that incorporates proven technology within an optimized configuration to enhance safety. EPR was originally developed through a joint effort between Framatome ANP and Siemens by incorporating the best technological features from the French and German nuclear reactor fleets into a cost-competitive product. Commercial EPR units are currently being built in Finland at the Olkiluoto site, and planned for France at the Flamanville site. In recent months, Framatome ANP announced their intention to market the EPR units to China in response to a request for vendor bids as well as their intent to pursue design certification in the United States under 10CFR52. The EPR safety philosophy is based on a deterministic consideration of defense-in-depth complemented by probabilistic analyses. Not only is the EPR designed to prevent and mitigate design basis accidents (DBAs), it employs an extra level of safety associated with severe accident response. Therefore, as a design objective, features are included to ensure that radiological consequences are limited such that the need for stringent counter measures, such as evacuation and relocation of the nearby population, can be reasonably excluded. This paper discusses some of the innovative features of the EPR to address severe accident challenges. (author)

  20. Dynamical state reduction in an EPR experiment

    Energy Technology Data Exchange (ETDEWEB)

    Bedingham, Daniel J [Blackett Laboratory, Imperial College, London SW7 2BZ (United Kingdom)

    2009-11-20

    A model is developed to describe state reduction in an EPR experiment as a continuous, relativistically invariant, dynamical process. The system under consideration consists of two entangled isospin particles each of which undergoes isospin measurements at spacelike separated locations. The equations of motion take the form of stochastic differential equations. These equations are solved explicitly in terms of random variables with a priori known probability distribution in the physical probability measure. In the course of solving these equations a correspondence is made between the state reduction process and the problem of classical nonlinear filtering. It is shown that the solution is covariant, violates Bell inequalities and does not permit superluminal signalling. It is demonstrated that the model is not governed by the free will theorem and it is argued that the claims of Conway and Kochen, that there can be no relativistic theory providing a mechanism for state reduction, are false.

  1. EPR design tools. Integrated data processing tools

    International Nuclear Information System (INIS)

    In all technical areas, planning and design have been supported by electronic data processing for many years. New data processing tools had to be developed for the European Pressurized Water Reactor (EPR). The work to be performed was split between KWU and Framatome and laid down in the Basic Design contract. The entire plant was reduced to a logical data structure; the circuit diagrams and flowsheets of the systems were drafted, the central data pool was established, the outlines of building structures were defined, the layout of plant components was planned, and the electrical systems were documented. Also building construction engineering was supported by data processing. The tasks laid down in the Basic Design were completed as so-called milestones. Additional data processing tools also based on the central data pool are required for the phases following after the Basic Design phase, i.e Basic Design Optimization; Detailed Design; Management; Construction, and Commissioning. (orig.)

  2. Asymmetric EPR entanglement in continuous variable systems

    CERN Document Server

    Wagner, Katherine; Armstrong, Seiji; Morizur, Jean-Francois; Lam, Ping Koy; Bachor, Hans-Albert

    2012-01-01

    Continuous variable entanglement can be produced in nonlinear systems or via interference of squeezed states. In many of optical systems, such as parametric down conversion or interference of optical squeezed states, production of two perfectly symmetric subsystems is usually used for demonstrating the existence of entanglement. This symmetry simplifies the description of the concept of entanglement. However, asymmetry in entanglement may arise naturally in a real experiment, or be intentionally introduced in a given quantum information protocol. These asymmetries can emerge from having the output beams experience different losses and environmental contamination, or from the availability of non-identical input quantum states in quantum communication protocols. In this paper, we present a visualisation of entanglement using quadrature amplitude plots of the twin beams. We quantitatively discuss the strength of asymmetric entanglement using EPR and inseparability criteria and theoretically show that the optimal...

  3. EPR's energy conversion system. Alstom's solutions

    International Nuclear Information System (INIS)

    ARABELLE steam turbines have been developed by Alstom to be used as the energy conversion system of light water reactors with high output power like the N4 PWR and the EPR. ARABELLE turbines cumulate 200.000 hours of service with a reliability ratio of 99.97 per cent. This series of slides presents the main features of the turbine including: the use of the simple flux, the very large shape of low pressure blades, the technology of welded rotors. The other main equipment like the alternator, the condenser, the moisture separator-reheaters, the circulating pumps that Alstom integrates in the energy conversion system have benefited with technological improvements that are also presented. (A.C.)

  4. Radiation protection issues for EPR reactor

    International Nuclear Information System (INIS)

    As part of the EPR (European Pressurized Reactor) project being deployed at Flamanville, EDF has pro actively made the decision to focus on radiation protection Radiation Protection aspects right from the start of the design phase, as it has done with nuclear safety. The approach adopted for managing Radiation Protection-significant activities has been to include all involved stakeholders - designers, licensee and contractor companies - in the three successive phases, starting with a survey among workers and designers, followed by a proposal review, and finally ending with the decision-making phase entrusted to an ALARA committee. The Radiation Protection target set by EDF for this new reactor is to engage in an effort of continuous improvement and optimisation, through benchmarking with the best performing plants of the fleet. The collective dose target is currently set at 0.35 Man Sv/year per unit. In addition to other aspects, efforts will focus on shortening the duration of the highest-dose jobs, with a new challenge being set for work performed in the reactor building during normal operations, the aim being to improve plant availability. The plan is for work to be performed 7 days prior to shutting down the reactor and 3 days afterwards, in order to make logistical arrangements for forthcoming jobs. Without this reduction, the estimated drop is currently 4.5% of annual dose. For this purpose, two areas have been set up in the E.P.R.'s reactor building: one no-go area for containing leaks from the primary circuit, and one accessible area for normal operations, separated from the no-go area by purpose-built ventilation equipment and facilities. To offer protection against radioactive flux (neutrons and high energy), Radiation Protection studies have resulted in the installation of a concrete floor and of nuclear shielding at the outlets of primary circuit pipes. Steam generator bunkers and pumps have also been reinforced. All these measures will ensure that the

  5. Análisis neuronal de variables fusificadas para la caracterización y determinación del rating de un puente de carretera

    OpenAIRE

    Pedro A. Hernández Delgado; Luis Roberto González Arestuche

    2010-01-01

    La toma de decisiones en la realización de actividades de conservación de puentes y su financiamiento, es la tarea fundamental dentro del Sistema de Gestión Integral de Puentes. La vitalidad de los puentes dentro del sistema vial de un país, obliga a los gobiernos a prestarle atención y dedicarles fondos presupuestarios para su garantía y conservación. La forma en la que estas asignaciones se realizan varía de un país a otro. Algunos emplean sistemas automatizados muy desarrollados y técnicas...

  6. EPR paradox, quantum nonlocality and physical reality

    Science.gov (United States)

    Kupczynski, M.

    2016-03-01

    Eighty years ago Einstein, Podolsky and Rosen demonstrated that instantaneous reduction of wave function, believed to describe completely a pair of entangled physical systems, led to EPR paradox. The paradox disappears in statistical interpretation of quantum mechanics (QM) according to which a wave function describes only an ensemble of identically prepared physical systems. QM predicts strong correlations between outcomes of measurements performed on different members of EPR pairs in far-away locations. Searching for an intuitive explanation of these correlations John Bell analysed so called local realistic hidden variable models and proved that correlations consistent with these models satisfy Bell inequalities which are violated by some predictions of QM and by experimental data. Several different local models were constructed and inequalities proven. Some eminent physicists concluded that Nature is definitely nonlocal and that it is acting according to a law of nonlocal randomness. According to these law perfectly random, but strongly correlated events, can be produced at the same time in far away locations and a local and causal explanation of their occurrence cannot be given. We strongly disagree with this conclusion and we prove the contrary by analysing in detail some influential finite sample proofs of Bell and CHSH inequalities and so called Quantum Randi Challenges. We also show how one can win so called Bell's game without violating locality of Nature. Nonlocal randomness is inconsistent with local quantum field theory, with standard model in elementary particle physics and with causal laws and adaptive dynamics prevailing in the surrounding us world. The experimental violation of Bell-type inequalities does not prove the nonlocality of Nature but it only confirms a contextual character of quantum observables and gives a strong argument against counterfactual definiteness and against a point of view according to which experimental outcomes are produced

  7. Can a wormhole be interpreted as an EPR pair?

    OpenAIRE

    Nikolic, H.

    2013-01-01

    Recently, Maldacena and Susskind arXiv:1306.0533 and Jensen and Karch arXiv:1307.1132 argued that a wormhole can be interpreted as an EPR pair. We point out that a convincing justification of such an interpretation would require a quantitative evidence that correlations between two ends of the wormhole are equal to those between the members of the EPR pair. As long as the existing results do not contain such evidence, the interpretation of wormhole as an EPR pair does not seem justified.

  8. The second international intercomparison on EPR tooth dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Wieser, A. E-mail: wieser@gsf.de; Mehta, K.; Amira, S.; Aragno, D.; Bercea, S.; Brik, A.; Bugai, A.; Callens, F.; Chumak, V.; Ciesielski, B.; Debuyst, R.; Dubovsky, S.; Duliu, O.G.; Fattibene, P.; Haskell, E.H.; Hayes, R.B.; Ignatiev, E.A.; Ivannikov, A.; Kirillov, V.; Kleschenko, E.; Nakamura, N.; Nather, M.; Nowak, J.; Onori, S.; Pass, B.; Pivovarov, S.; Romanyukha, A.; Scherbina, O.; Shames, A.I.; Sholom, S.; Skvortsov, V.; Stepanenko, V.; Tikounov, D.D.; Toyoda, S

    2000-12-15

    Eighteen international EPR laboratories participated in the second intercomparison programme. Each participant had to prepare enamel samples and evaluate the absorbed dose from molars that were irradiated in vitro in the range 0-1000 mGy. The objective of the programme was to bring together all methods which are currently applied by different laboratories for EPR dose reconstruction and to demonstrate the present state of dosimetry. An overview of the essential features of the different methods is presented. The current accuracy of EPR tooth enamel dosimetry under defined conditions of irradiation is evaluated.

  9. Low symmetry EPR spectra in trigonal double molybdates

    International Nuclear Information System (INIS)

    Gd3+ EPR spectra in trigonal double molybdates with a high asymmetry of angular dependence relative to a basal plane is studied. The EPR spectra are shown to correspond to paramagnetic ions in positions with the anti3 local symmetry. The parameters of a spin-hamiltonian for Gd3+ in KSc(MoO4)2 and RbSc(MoO4)2 are determined. Low symmetry of the EPR spectra enables to refer a number of isostructural trigonal double molybdates and tungstates to the Dsub(3d)sup(4)=P anti 3c1(z=2) space group

  10. The second international intercomparison on EPR tooth dosimetry

    International Nuclear Information System (INIS)

    Eighteen international EPR laboratories participated in the second intercomparison programme. Each participant had to prepare enamel samples and evaluate the absorbed dose from molars that were irradiated in vitro in the range 0-1000 mGy. The objective of the programme was to bring together all methods which are currently applied by different laboratories for EPR dose reconstruction and to demonstrate the present state of dosimetry. An overview of the essential features of the different methods is presented. The current accuracy of EPR tooth enamel dosimetry under defined conditions of irradiation is evaluated

  11. EPR of radiation defects in lithium-oxyfluoride glass ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Fedotovs, A; Rogulis, U; Sarakovskis, A; Dimitrocenko, L, E-mail: andris-f@navigator.l [Institute of Solid State Physics, University of Latvia, Kengaraga st. 8, LV-1063, Riga (Latvia)

    2010-11-01

    We studied oxyfluoride composites based on lithium silicate glasses with yttrium fluorides and rare-earth dopants. The electron paramagnetic resonance (EPR) has been used to obtain information about radiation induced defects in these materials. Spectra have been measured before and after X-ray irradiation at room temperature and at liquid nitrogen temperature. Fluoride crystallites within samples were created by means of thermal treatment at specific temperatures. EPR spectra of radiation induced defects in oxyfluoride glass ceramics, in which crystallites have not been yet created, show no explicit hfs interaction of fluorine nuclei. However, in glass ceramics, which already contains fluoride crystallites, the hfs characteristic to fluorine nuclei appears in the EPR spectra. EPR hyperfine structure could be explained within a model of an F-type centre in YF{sub 3} crystalline phase.

  12. EPR of radiation defects in lithium-oxyfluoride glass ceramics

    International Nuclear Information System (INIS)

    We studied oxyfluoride composites based on lithium silicate glasses with yttrium fluorides and rare-earth dopants. The electron paramagnetic resonance (EPR) has been used to obtain information about radiation induced defects in these materials. Spectra have been measured before and after X-ray irradiation at room temperature and at liquid nitrogen temperature. Fluoride crystallites within samples were created by means of thermal treatment at specific temperatures. EPR spectra of radiation induced defects in oxyfluoride glass ceramics, in which crystallites have not been yet created, show no explicit hfs interaction of fluorine nuclei. However, in glass ceramics, which already contains fluoride crystallites, the hfs characteristic to fluorine nuclei appears in the EPR spectra. EPR hyperfine structure could be explained within a model of an F-type centre in YF3 crystalline phase.

  13. EPR and NMR detection of transient radicals and reaction products

    International Nuclear Information System (INIS)

    Magnetic resonance methods in radiation chemistry are illustrated. The most recent developments in pulsed EPR and NMR studies in pulse radiolysis are outlined with emphasis on the study of transient radicals and their reaction products. 12 figures

  14. Reconfiguring Cooperative Work by Visualizing EPR on Large Projected Screens

    DEFF Research Database (Denmark)

    Simonsen, Jesper

    Simonsen, J. (2006): Reconfiguring Cooperative Work by Visualizing EPR on Large Projected Screens, Paper presented at the PDC 2006 workshop on: Reconfiguring Healthcare: Issues in Computer Supported Cooperative Work in Healthcare Environments. Participatory Design Conference, Trento, Italy, August...

  15. Software for evaluation of EPR-dosimetry performance

    International Nuclear Information System (INIS)

    Electron paramagnetic resonance (EPR) with tooth enamel is a method extensively used for retrospective external dosimetry. Different research groups apply different equipment, sample preparation procedures and spectrum processing algorithms for EPR dosimetry. A uniform algorithm for description and comparison of performances was designed and implemented in a new computer code. The aim of the paper is to introduce the new software 'EPR-dosimetry performance'. The computer code is a user-friendly tool for providing a full description of method-specific capabilities of EPR tooth dosimetry, from metrological characteristics to practical limitations in applications. The software designed for scientists and engineers has several applications, including support of method calibration by evaluation of calibration parameters, evaluation of critical value and detection limit for registration of radiation-induced signal amplitude, estimation of critical value and detection limit for dose evaluation, estimation of minimal detectable value for anthropogenic dose assessment and description of method uncertainty. (authors)

  16. Electron Paramagnetic Resonance Imaging: 1. CW-EPR Imaging

    Indian Academy of Sciences (India)

    2016-07-01

    Twentieth century bore witness to remarkable scientists whohave advanced our understanding of the brain. Among them,EPR (Electron Paramagnetic Resonance) imaging is particularlyuseful in monitoring hypoxic zones in tumors which arehighly resistant to radiation and chemotherapeutic treatment.This first part of the article covers aspects of CW(continuous wave) imaging with details of FT (pulsed FourierTransform)-EPR imaging covered in Part 2, to be publishedin the next issue of Resonance.

  17. Lorentz symmetry breaking effects on relativistic EPR correlations

    Energy Technology Data Exchange (ETDEWEB)

    Belich, H. [Universidade Federal do Espirito Santo, Departamento de Fisica e Quimica, Vitoria, ES (Brazil); Furtado, C.; Bakke, K. [Universidade Federal da Paraiba, Departamento de Fisica, Caixa Postal 5008, Joao Pessoa, PB (Brazil)

    2015-09-15

    Lorentz symmetry breaking effects on relativistic EPR (Einstein-Podolsky-Rosen) correlations are discussed. From the modified Maxwell theory coupled to gravity, we establish a possible scenario of the Lorentz symmetry violation and write an effective metric for the Minkowski spacetime. Then we obtain the Wigner rotation angle via the Fermi-Walker transport of spinors and consider the WKB (Wentzel-Kramers-Brillouin) approximation in order to study the influence of Lorentz symmetry breaking effects on the relativistic EPR correlations. (orig.)

  18. EPR study on non- and gamma-irradiated herbal pills

    Science.gov (United States)

    Aleksieva, K.; Lagunov, O.; Dimov, K.; Yordanov, N. D.

    2011-06-01

    The results of EPR studies on herbal pills of marigold, hawthorn, yarrow, common balm, tutsan, nettle and thyme before and after gamma-irradiation are reported. Before irradiation all samples exhibit one weak singlet EPR line with a g-factor of 2.0048±0.0005. After irradiation herbal pills could be separated in two groups according to their EPR spectra. Radiation-induced free radicals in pills of marigold, yarrow, nettle, tutsan and thyme could be attributed mainly to saccharide excipients. Tablets of hawthorn and common balm show "cellulose-like" EPR spectrum, superimposed on partly resolved carbohydrate spectrum, due to the active part (herb) and inulin, which is present in the pills as an excipient. Fading study of the radiation-induced EPR signals confirms that sugar radicals are more stable than cellulose species. The reported results show that the presence of characteristic EPR spectra of herbal pills due to excipients or active part can be used as unambiguous proof of radiation processing within 35 or more days after irradiation.

  19. Influence of nails polish in EPR dosimetry with human nails

    International Nuclear Information System (INIS)

    In the last decade human nails have been investigated as a possible biological indicator of exposure to ionizing radiation. Radiation-induced radicals detected by Electron Paramagnetic Resonance (EPR) spectroscopy can be used to quantify the received dose. However, possible additional EPR signals due to nail polish have not been yet investigated. An additional signal is observed with some polishes. This signal, attributed to the iron oxide used as dark pigments in colour polishes, occupies the range of EPR spectrum covered also by the radiation-induced signals, so it can overlap and completely masks the radiation-induced signals, making any dose estimation impossible. Remover solvents allow for the complete eliminate of EPR signals from polishes without modifying the native signals in nails also called BKS in the literature. This may possibly expand the use of EPR nail dosimetry to potentially exposed individuals that have nail polishes on their nails (not eligible for the use of this technique otherwise) at the time of sample collection. - Highlights: • Example of EPR signals from un-irradiated nails polishes are reported. • Ferro -magnetism can be observed in polishes with iron oxides. • Signals from nails polished can eliminated by acetone. • Acetone can be used for sample preparation

  20. EPR study on non- and gamma-irradiated herbal pills

    International Nuclear Information System (INIS)

    The results of EPR studies on herbal pills of marigold, hawthorn, yarrow, common balm, tutsan, nettle and thyme before and after gamma-irradiation are reported. Before irradiation all samples exhibit one weak singlet EPR line with a g-factor of 2.0048±0.0005. After irradiation herbal pills could be separated in two groups according to their EPR spectra. Radiation-induced free radicals in pills of marigold, yarrow, nettle, tutsan and thyme could be attributed mainly to saccharide excipients. Tablets of hawthorn and common balm show 'cellulose-like' EPR spectrum, superimposed on partly resolved carbohydrate spectrum, due to the active part (herb) and inulin, which is present in the pills as an excipient. Fading study of the radiation-induced EPR signals confirms that sugar radicals are more stable than cellulose species. The reported results show that the presence of characteristic EPR spectra of herbal pills due to excipients or active part can be used as unambiguous proof of radiation processing within 35 or more days after irradiation.

  1. EPR study on non- and gamma-irradiated herbal pills

    Energy Technology Data Exchange (ETDEWEB)

    Aleksieva, K., E-mail: katerina_bas@abv.b [Institute of Catalysis, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria); Lagunov, O. [Institute of Catalysis, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria); Dimov, K. [Institute of Cryobiology and Food Technologies, 1162 Sofia (Bulgaria); Yordanov, N.D. [Institute of Catalysis, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria)

    2011-06-15

    The results of EPR studies on herbal pills of marigold, hawthorn, yarrow, common balm, tutsan, nettle and thyme before and after gamma-irradiation are reported. Before irradiation all samples exhibit one weak singlet EPR line with a g-factor of 2.0048{+-}0.0005. After irradiation herbal pills could be separated in two groups according to their EPR spectra. Radiation-induced free radicals in pills of marigold, yarrow, nettle, tutsan and thyme could be attributed mainly to saccharide excipients. Tablets of hawthorn and common balm show 'cellulose-like' EPR spectrum, superimposed on partly resolved carbohydrate spectrum, due to the active part (herb) and inulin, which is present in the pills as an excipient. Fading study of the radiation-induced EPR signals confirms that sugar radicals are more stable than cellulose species. The reported results show that the presence of characteristic EPR spectra of herbal pills due to excipients or active part can be used as unambiguous proof of radiation processing within 35 or more days after irradiation.

  2. EPC projects for EPR Flamanville 3 NPP

    International Nuclear Information System (INIS)

    IBERDROLA Ingenieria y Construccion is carrying out a handful of activities in the EPR Flamanville 3 -FA3 NPP- context since 2007 matching oriented to position the company in the emerging marketplace of new nuclear power plants Generation III+, whose expectation for the next years is highly promising. IBERDROLA Ingenieria y Construccion leads 5 EPC -Engineering, Procurement and Commissioning- projects for FA3 NPP from the Nuclear Island till Sea Water Pumping Station as follows: - Design, procurement. fabrication, installation and testing of 21 shell and tubes heat-exchangers for the nuclear island. 12 out of these 17 HXs are conventional and will be designed according to ASME BPV code Section VIII and have to comply with PED 97/23/CE and ESPN. The remaining 5 HXs are nuclear and will be designed according to ASME BPV code Section III and have also to comply with PED and ESPN. - Design, procurement, fabrication and assembly of 9 demineralizers for different plant systems. Three of these Important To Safety (IPS) equipments have been manufactured according with ASME VIII codes and six of them with EN 13445 code plus additional requirements to comply with PED and final client requirements for nuclear island. - Design, fabrication and installation of qualified travelling water screening filters. The equipments furnished will be two nuclear safety qualified filters and associated equipment (cleaning water system and control system). Additionally some auxiliary devices such as grids, automatic trash rakes and stop gates are included in the contract. - Engineering, procurement, fabrication, erection and commissioning for the condensate treatment plant. This system includes a demineralizer tank, 5 filters, reactive injection mixer, pneumatic and manual valves, piping and instrumentation and control systems. - Engineering, procurement erection and commissioning for the electro-chlorination plant to protect the IPS piping for Condensate Water System for FA3. This system

  3. EPC projects for EPR Flamanville 3 NPP

    Energy Technology Data Exchange (ETDEWEB)

    Diaz, J.I.; Polo, J.; Aymerich, E.; Cubian, B. [Nuclear Generation Department, Iberdrola Ingenieria y Construccion, Avda. Manoteras 20, 28050 Madrid (Spain)

    2010-07-01

    IBERDROLA Ingenieria y Construccion is carrying out a handful of activities in the EPR Flamanville 3 -FA3 NPP- context since 2007 matching oriented to position the company in the emerging marketplace of new nuclear power plants Generation III+, whose expectation for the next years is highly promising. IBERDROLA Ingenieria y Construccion leads 5 EPC -Engineering, Procurement and Commissioning- projects for FA3 NPP from the Nuclear Island till Sea Water Pumping Station as follows: - Design, procurement. fabrication, installation and testing of 21 shell and tubes heat-exchangers for the nuclear island. 12 out of these 17 HXs are conventional and will be designed according to ASME BPV code Section VIII and have to comply with PED 97/23/CE and ESPN. The remaining 5 HXs are nuclear and will be designed according to ASME BPV code Section III and have also to comply with PED and ESPN. - Design, procurement, fabrication and assembly of 9 demineralizers for different plant systems. Three of these Important To Safety (IPS) equipments have been manufactured according with ASME VIII codes and six of them with EN 13445 code plus additional requirements to comply with PED and final client requirements for nuclear island. - Design, fabrication and installation of qualified travelling water screening filters. The equipments furnished will be two nuclear safety qualified filters and associated equipment (cleaning water system and control system). Additionally some auxiliary devices such as grids, automatic trash rakes and stop gates are included in the contract. - Engineering, procurement, fabrication, erection and commissioning for the condensate treatment plant. This system includes a demineralizer tank, 5 filters, reactive injection mixer, pneumatic and manual valves, piping and instrumentation and control systems. - Engineering, procurement erection and commissioning for the electro-chlorination plant to protect the IPS piping for Condensate Water System for FA3. This system

  4. Avaliação da exeqüibilidade, eficácia e segurança do transplante lamelar semi-automatizado de córnea Evaluation of performance, efficacy and safety of semi-automated lamellar keratoplasty

    Directory of Open Access Journals (Sweden)

    Núbia Cristina de Freitas Maia

    2006-12-01

    Full Text Available OBJETIVO: Avaliar a exeqüibilidade, eficácia e segurança do uso de microcerátomo e câmara anterior artificial para o transplante lamelar (sistema ALTK®. MÉTODOS: 21 olhos com opacidades corneanas superficiais foram submetidos ao transplante lamelar semi-automatizado de córnea. Nos olhos receptores a ceratectomia foi realizada de modo semelhante a uma cirurgia refrativa. As lamelas doadoras foram obtidas a partir de botões esclero-corneanos utilizando o mesmo microcerátomo e uma câmara anterior artificial. As medidas das espessuras corneanas foram feitas através da biomicroscopia ultra-sônica. RESULTADOS: As cirurgias obtiveram êxito em 19 olhos. Em 80% das lamelas obtidas em córneas doadoras e em 84,2% das lamelas em olhos receptores houve uma variação de até 0,5 mm do diâmetro desejado. Verificou-se alta semelhança entre as espessuras das lamelas obtidas nos olhos receptores e lamelas doadoras. Obteve-se acuidade visual corrigida pós-operatória igual ou superior a 20/40 em 52,6% dos olhos. Foram observadas complicações como diâmetro inadequado da lamela, perfuração intra-operatória no olho receptor e ectasia corneana pós-operatória (um caso. CONCLUSÕES: O transplante lamelar semi-automatizado de córnea mostrou-se exequível pela reprodutibilidade das espessuras e diâmetros das lamelas; eficaz pela melhora da acuidade visual pós-operatória e seguro, devido ao baixo índice de complicações cirúrgicas.PURPOSE: To evaluate the feasibility, efficacy and safety of a manual microkeratome and an artificial anterior chamber for lamellar keratoplasty (ALTK® system. METHODS: Twenty-one eyes with superficial corneal opacities were submitted to semi-automated lamellar keratectomy. In recipient eyes keratectomy was performed as in refractive surgery. The donor flap was removed from the preserved corneal shell using the same microkeratome and an artificial anterior chamber. Lamella thickness was measured through

  5. Pulsed EPR for studying silver clusters

    Science.gov (United States)

    Michalik, J.; Wasowicz, T.; Sadlo, J.; Reijerse, E. J.; Kevan, L.

    1996-01-01

    The cationic silver clusters of different nuclearity have been produced by radiolysis of zeolite A and SAPO molecular sieves containing Ag + as exchangeable cations. The pulsed EPR spectroscopy has been applied for studying the local environment of silver cluster in order to understand the mechanism of cluster formation and stabilization. The electron spin echo modulation (ESEM) results on Ag 6n+ cluster in dehydration zeolite A indicate that the hexameric silver is stabilized only in sodalite cages which are surrounded by α-cages containing no water molecules. Trimeric silver clusters formed in hydrated A zeolites strongly interact with water, thus the paramagnetic center can be considered as a cluster-water adduct. In SAPO-molecular sieves, silver clusters are formed only in the presence of adsorbed alcohol molecules. From ESEM it is determined that Ag 4n+ in SAPO-42 is stabilized in α-cages, where it is directly coordinated by two methanol molecules. Dimeric silver, Ag 2+ in SAPO-5 and SAPO-11 is located in 6-ring channels and interacts with three CH 3OH molecules, each in different 10-ring or 12-ring channels. The differences of Ag 2+ stability in SAPO-5 and SAPO-11 are also discussed.

  6. Pulsed EPR for studying silver clusters

    International Nuclear Information System (INIS)

    The cationic silver clusters of different nuclearity have been produced by radiolysis of zeolite A and SAPO molecular sieves containing Ag+ as exchangeable cations. The pulsed EPR spectroscopy has been applied for studying the local environment of silver cluster in order to understand the mechanism of cluster formation and stabilization. the electron spin echo modulation (ESEM) results on Ag6n+ cluster in dehydration zeolite A indicate that the hexameric silver is stabilized only in sodalite cages which are surrounded by α-cages containing no water molecules. Trimeric silver clusters formed in hydrated A zeolites strongly interact with water, thus the paramagnetic center can be considered as a cluster-water adduct. In SAPO-molecular sieves, silver clusters are formed only in the presence of adsorbed alcohol molecules. From ESEM it is determined that Ag4n+ in SAPO-42 is stabilized in α cages, where it is directly coordinated by two methanol molecules. Dimeric silver, Ag2+ in SAPO-5 and SAPO-11 is located in 6-ring channels and interacts with three CH3OH molecules, each in different 10 ring or 12 ring channels. The differences of Ag2+ stability in SAPO-5 and SAPO-11 are also discussed. (Author)

  7. The European Pressurized Water Reactor (EPR). Proceedings

    International Nuclear Information System (INIS)

    In October 1997 the German Nuclear Society (KTG) and the French Nuclear Society (SFEN) jointly organized an international conference about the progress achieved in developing the European Pressurized Water Reactor (EPR). It was the second conference of it's kind. The first one had successfully been held at Strasbourg in 1995. This date had been chosen since in May 1997 the so called basic design phase had been finalized and so it was the ideal time to present the results and findings of this Franco-German project to the international public. This book which has been issued at the beginning of this conference covers all papers that were available at that time i.e. most of the results of the conference. Those papers delivered there after can be ordered by use of the voucher attached to this book. In part 1 you may find those papers of the plenary session report. Part 2 contains so called compacts of papers presented during poster sessions. (orig.)

  8. Asymmetric EPR entanglement in continuous variable systems

    International Nuclear Information System (INIS)

    Continuous variable entanglement can be produced in nonlinear systems or via the interference of squeezed states. In many optical systems such as parametric down conversion, the production of two perfectly symmetric subsystems is usually assumed when demonstrating the existence of entanglement. This symmetry simplifies the description of entanglement. However, asymmetry in entanglement may arise naturally in a real experiment, or be intentionally introduced in a given quantum information protocol. These asymmetries can emerge from having the output beams experience different losses and environmental contamination, or from the availability of non-identical input quantum states in quantum communication protocols. In this paper, we present a visualization of entanglement using quadrature amplitude plots of the twin beams. We quantitatively discuss the strength of asymmetric entanglement using EPR and inseparability criteria and theoretically show that the optimal beamsplitter ratio for entanglement is dependent on the asymmetries and may not be 50 : 50. To support this theory, we present experimental results showing one particular asymmetric entanglement where a 78 : 22 beamsplitter is optimal for observing entanglement. (paper)

  9. Methodological aspects of EPR dosimetry with teeth

    International Nuclear Information System (INIS)

    EPR dosimetry with tooth enamel is known today as one of the most reliable and accurate methods of retrospective dosimetry. In the present study a comprehensive analysis of influence of the major confounding factors (solar UV exposure and dental X-ray diagnostic procedures) on the accuracy of accidental dose reconstruction is given. In this analysis, the facts known from literature as well as own authors' results were considered. Among the latter it is worth to mention study of doses in enamel caused by X-ray diagnostic procedures as well as investigation of dose profiles in front teeth, which are most affected to solar radiation. As a main result, the variant of dosimetric technique is proposed. It comprises the optimal combination of strongest sides of existing techniques which allows to conduct routine reconstruction of accidental doses as low as few tens of mGy with errors of the same order of magnitude. The proposed technique is primarily destined for dosimetry of Chernobyl liquidators, but could be used for reconstruction of doses of other over-exposed categories. (orig.)

  10. EPR by Areva. The path of greatest certainty

    International Nuclear Information System (INIS)

    AREVA's Evolutionary Power Reactor (EPR) is the first Generation III+ reactor design currently being built to answer the world's growing demand for clean and reliable electricity generation. Already under construction in Finland, France and China, the EPR is also being considered by America, United Kingdom, South Africa and other countries for the development of their nuclear fleet. The EPR is now clearly destined to become the mainstay of standardized, efficient reactor fleets around the globe. AREVA's EPR incorporates unbeatable know-how provided by an uninterrupted track record of reactor building activities and backed by decades of feedback experience from operating PWRs, including the most recent. The EPR is a Franco-German initiative which benefited from the stringent scrutiny of safety authorities from both countries, at each stage of the project. The EPR has already secured construction licenses from two of the world's most demanding safety authorities in France and Finland and is currently in line for a design certification and a combined construction and operating license (COL) in the USA. It is also taking part in the licensing process recently launched in the United Kingdom. Europe's leading utilities have granted the EPR their approval under the 'European Utilities Requirements' and have further expressed individual interest in the design and performance of the EPR for their businesses. AREVA is the only Gen III+ reactor constructor in the world with ongoing building experience. To date, AREVA is the only vendor who has the necessary field experience that future customers can benefit: - Detailed design completed; - Experience feedback from 87 PWR; - 3 projects going on; - Continuous PWR experience in design and construction. Close to 100% of the EPR primary circuit heavy components are sourced directly from AREVA's integrated plants. Engineering, manufacturing, services and fuel cycle management are totally integrated and mastered by AREVA. From its

  11. Econometría para la evaluación de políticas públicas con Stata: introducción y análisis de datos

    OpenAIRE

    Carlos Giovanni González Espitia

    2011-01-01

    Es el primero de una serie de documentos de carácter académico sobre el uso en econometría del software Stata. En econometría es necesario el uso continuo de software especializado tanto en la docencia como en la investigación aplicada. El objetivo de este documento es introducir al lector en el manejo de Stata, posiblemente el software econométrico más popular y con las herramientas predefinidas más adecuadas del cálculo automatizado para la docencia y la investigación en economía.

  12. DIREPI: Sistema para el cálculo a resistencia de recipientes sometidos a presión interna // DIREPI: System for the resistance calculation of recipients with internal pressure

    OpenAIRE

    L. S. Flores Bernal; S. A. Marín Hernández; D. Romero García; E. Turiño Millán

    1999-01-01

    El trabajo muestra la confección de un software para el cálculo a resistencia de recipientes sometidos a presión interna y construidosde acero, aborda también las ventajas que reporta el tener automatizado la metodología de trabajo por la calidad de los resultadosfinales que se obtienen y la fiabilidad de los mismos, el sistema posee una salida gráfica por AutoCAD que permite obtener losplanos de taller de los componentes de los recipientes diseñados.Palabras claves: CADD, CAD, diseño, cálcul...

  13. Development of a new dosimeter of EPR based on lactose

    International Nuclear Information System (INIS)

    50 years have passed since was proposed using the amino acid alanine as dosimeter advantage the phenomenon of electron paramagnetic resonance (EPR); this dosimetric method has reached a highly competitive level regarding others dosimetry classic methods, for example the thermoluminescence or the use of Fricke dosimeters, to measure high dose of radiation. In this type of materials, the free radicals induced by the radiation are stable and their concentration is proportional to the absorbed dose may be determined by the amplitude pick to pick of the first derived of the EPR absorption spectrum. The obtained results studying the EPR response of lactose tablets elaborated in the Universidad Autonoma Metropolitana, Unidad Iztapalapa are presented. The tablets were irradiated with gamma radiation of 60Co in the irradiator Gamma beam 651-Pt of the Instituto de Ciencias Nucleares de la Universidad Nacional Autonoma de Mexico to a dose rate of 8 kGy-h-1 and their EPR response in a EPR spectrometer e-scan Bruker. The obtained response in function of the dose was lineal in the interval of 1 at 10 kGy. The lactose sensibility was compared with the l-alanine, used as reference, and the result was consistently 0.25 of this. Due to the linearity shown in the interval of used dose and their low production cost, we conclude that the lactose is a promissory option for the dosimetry of high dose of radiation. (author)

  14. ER=EPR, GHZ, and the Consistency of Quantum Measurements

    CERN Document Server

    Susskind, Leonard

    2014-01-01

    This paper illustrates various aspects of the ER=EPR conjecture.It begins with a brief heuristic argument, using the Ryu-Takayanagi correspondence, for why entanglement between black holes implies the existence of Einstein-Rosen bridges. The main part of the paper addresses a fundamental question: Is ER=EPR consistent with the standard postulates of quantum mechanics? Naively it seems to lead to an inconsistency between observations made on entangled systems by different observers. The resolution of the paradox lies in the properties of multiple black holes, entangled in the Greenberger-Horne-Zeilinger pattern. The last part of the paper is about entanglement as a resource for quantum communication. ER=EPR provides a way to visualize protocols like quantum teleportation. In some sense teleportation takes place through the wormhole, but as usual, classical communication is necessary to complete the protocol.

  15. Using Gunn diodes as Microwave Sources in EPR spectrometry

    International Nuclear Information System (INIS)

    Microwave solid-state components have gained wide acceptance in a large frequency range (1-100 GHz) during the last years. A dominant trend was the building of microwave oscillators using Gunn diodes. These devices show excellent frequency stability and low internal noise. Gunn diodes were used as microwave sources in some experimental EPR spectrometers whose design generally proves more simplified. The application capabilities of Gunn diodes in a classical EPR spectrometer designed and built at the Institute of Atomic Physics, Bucharest, are described. The sensitivity of EPR spectrometers as a function of the microwave source noise is pointed out. The results have been compared to others obtained from the same spectrometer with a reflex clystron oscillator phase-locked to a harmonic of a crystal oscillator. (author)

  16. ER=EPR, GHZ, and the consistency of quantum measurements

    Energy Technology Data Exchange (ETDEWEB)

    Susskind, Leonard [Stanford Institute for Theoretical Physics and Department of Physics, Stanford University, Stanford, CA (United States)

    2016-01-15

    This paper illustrates various aspects of the ER=EPR conjecture. It begins with a brief heuristic argument, using the Ryu-Takayanagi correspondence, for why entanglement between black holes implies the existence of Einstein-Rosen bridges. The main part of the paper addresses a fundamental question: Is ER=EPR consistent with the standard postulates of quantum mechanics? Naively it seems to lead to an inconsistency between observations made on entangled systems by different observers. The resolution of the paradox lies in the properties of multiple black holes, entangled in the Greenberger-Horne-Zeilinger pattern. The last part of the paper is about entanglement as a resource for quantum communication. ER=EPR provides a way to visualize protocols like quantum teleportation. In some sense teleportation takes place through the wormhole, but as usual, classical communication is necessary to complete the protocol. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  17. EPR structure of the gamma irradiated alanine spectrum

    International Nuclear Information System (INIS)

    In this study is shown that the broadened five-line EPR pattern of the gamma irradiated alanine possibly decomposes into a more complex pattern when the recorded spectrum is subject to an operation of deconvolution. The EPR powder spectra of gamma irradiated DL- and L-alanine with and without binders are analysed. In all recorded spectra, each observed line is resolved into an asymmetrical triplet when a Gaussian distribution of 8.2 gauss width is removed, by deconvolution, from the observed spectrum. On the other hand, from a simple fitting analysis carried out on the original data, one encounters that some calculated relations between characteristic parameters, such as intensity ratios, deviate consistently from assumed height ratios. Both, from deconvolution and fitting results, a different structure is suggested for the observed broadened five-line EPR pattern of γ-irradiated powder DL- and L-alanine. (Author)

  18. Retrospective dosimetry using EPR and TL techniques: a status report

    International Nuclear Information System (INIS)

    Methods of retrospective dosimetry, including luminescence and electron paramagnetic resonance spectroscopy (EPR), rely on measurement of accident dose absorbed by naturally occurring materials - ceramics in the case of both thermoluminescence (TL) and optically stimulated luminescence (OSL) and organic materials and bio- minerals in the case of EPR. Each of these methods relies on measurement of radiation defects resulting from accidental exposure. Since defects also result from natural sources of radiation over the lifetime of a sample, analysis is usually restricted to materials for which the natural dose may be determined and subtracted from the measured cumulative dose. Luminescence dating techniques rely heavily on an accurate assessment of cumulative dose from natural radiation sources, and dating research has provided us with the bulk of our knowledge in this area. Virtually all of the work on natural dose determination can be directly applied to retrospective techniques. With EPR techniques the cumulative dose from diagnostic x- rays is also of importance

  19. In vivo EPR measurement of glutathione in tumor-bearing mice using improved disulfide biradical probe

    OpenAIRE

    Roshchupkina, Galina I.; Bobko, Andrey A.; Bratasz, Anna; Reznikov, Vladimir A.; Kuppusamy, Periannan; Khramtsov, Valery V.

    2008-01-01

    Disulfide nitroxide biradicals, DNB, have been used for glutathione, GSH, measurements by X-band electron paramagnetic resonance, EPR, in various cells and tissues. In the present paper, the postulated potential use of DNB for EPR detection of GSH in vivo was explored. Isotopic substitution in the structure of the DNB was performed for the enhancement of its EPR spectral properties. 15N substitution in the NO fragment of the DNB decreased the number of EPR spectral lines and resulted in an ap...

  20. Implementing a new EPR lineshape parameter for organic radicals in carbonaceous matter

    OpenAIRE

    Bourbin, Mathilde; Du, Yann Le; Binet, Laurent; Gourier, Didier

    2013-01-01

    Background Electron Paramagnetic Resonance (EPR) is a non-destructive, non-invasive technique useful for the characterization of organic moieties in primitive carbonaceous matter related to the origin of life. The classical EPR parameters are the peak-to-peak amplitude, the linewidth and the g factor; however, such parameters turn out not to suffice to fully determine a single EPR line. Results In this paper, we give the definition and practical implementation of a new EPR parameter based on ...

  1. Resolving the EPR Paradox for the Case of entangled Photons

    CERN Document Server

    Muchowski, Eugen

    2016-01-01

    A system of two polarized photons in singlet state appears as being in one of two product states independent of any measurement. These states depend on the selected polarization angles. With the polarizers on either side perpendicular to each other, both photons pass the polarizers without any disturbance. Action at a distance is therefore not needed to explain the results of the measurements. In general, the elements of physical reality demanded by EPR are the polarization states of the two photons of the entangled pair. As these are local elements in the regions of space of the polarizers the EPR paradox for the case of entangled photons can be regarded as resolved.

  2. The inner containment of an EPR trademark pressurized water reactor

    Energy Technology Data Exchange (ETDEWEB)

    Ostermann, Dirk; Krumb, Christian; Wienand, Burkhard [AREVA GmbH, Offenbach (Germany)

    2014-08-15

    On February 12, 2014 the containment pressure and subsequent leak tightness tests on the containment of the Finnish Olkiluoto 3 EPR trademark reactor building were completed successfully. The containment of an EPR trademark pressurized water reactor consists of an outer containment to protect the reactor building against external hazards (such as airplane crash) and of an inner containment that is subjected to internal overpressure and high temperature in case of internal accidents. The current paper gives an overview of the containment structure, the design criteria, the validation by analyses and experiments and the containment pressure test.

  3. A new causal interpretation of EPR-B experiment

    Science.gov (United States)

    Gondran, Michel; Gondran, Alexandre

    2012-12-01

    In this paper we study a two-step version of EPR-B experiment, the Bohm version of the Einstein-Podolsky-Rosen experiment. Its theoretical resolution in space and time enables us to refute the classic "impossibility" to decompose a pair of entangled atoms into two distinct states, one for each atom. We propose a new causal interpretation of the EPR-B experiment where each atom has a position and a spin while the singlet wave function verifies the two-body Pauli equation. In conclusion we suggest a physical explanation of non-local influences, compatible with Einstein's point of view on relativity.

  4. EPR studies of gamma-irradiated taurine single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Bulut, A. E-mail: abulut@samsun.omu.edu.tr; Karabulut, B.; Tapramaz, R.; Koeksal, F

    2000-04-01

    An EPR study of gamma-irradiated taurine [C{sub 2}H{sub 7}NO{sub 3}S] single crystal was carried out at room temperature. The EPR spectra were recorded in the three at mutually perpendicular planes. There are two magnetically distinct sites in monoclinic lattice. The principle values of g and hyperfine constants for both sites were calculated. The results have indicated the presence of {sup 32}SO{sup -}{sub 2} and {sup 33}SO{sup -}{sub 2} radicals. The hyperfine values of {sup 33}SO{sup -}{sub 2} radical were used to obtain O-S-O bond angle for both sites.

  5. EPR studies of gamma-irradiated taurine single crystals

    Science.gov (United States)

    Bulut, A.; Karabulut, B.; Tapramaz, R.; Köksal, F.

    2000-04-01

    An EPR study of gamma-irradiated taurine [C 2H 7NO 3S] single crystal was carried out at room temperature. The EPR spectra were recorded in the three at mutually perpendicular planes. There are two magnetically distinct sites in monoclinic lattice. The principle values of g and hyperfine constants for both sites were calculated. The results have indicated the presence of 32ṠO -2 and 33ṠO -2 radicals. The hyperfine values of 33ṠO -2 radical were used to obtain O-S-O bond angle for both sites.

  6. EPR studies of gamma-irradiated taurine single crystals

    International Nuclear Information System (INIS)

    An EPR study of gamma-irradiated taurine [C2H7NO3S] single crystal was carried out at room temperature. The EPR spectra were recorded in the three at mutually perpendicular planes. There are two magnetically distinct sites in monoclinic lattice. The principle values of g and hyperfine constants for both sites were calculated. The results have indicated the presence of 32SO-2 and 33SO-2 radicals. The hyperfine values of 33SO-2 radical were used to obtain O-S-O bond angle for both sites

  7. EPR and NMR studies of amorphous aluminum borates

    OpenAIRE

    Simon, S.; Pol, A.; Reijerse, E.J.; Kentgens, A.P.M.; Moorsel, G.J.M.P. van; de Boer, E

    1994-01-01

    Amorphous aluminium borates, Al2(1–x)B2xO3 with O [less-than-or-eq]x[less-than-or-eq] 0.5, prepared from mixtures of aluminium nitrate, boric acid and glycerol, have been studied by EPR and 27Al MASNMR as a function of composition and heat-treatment temperature (Tt[less-than-or-eq] 860 °C). EPR studies showed the presence of physisorbed NO2, NO and O2 molecules, produced by decomposition reactions during the thermal treatment. The O2 molecules in the gaseous state were observed in a narrow te...

  8. EPR trademark project delivery. The value of experience

    International Nuclear Information System (INIS)

    We are building the EPR trademark reactor fleet. Together. With four EPR trademark projects under construction in the world, AREVA has unrivalled experience in the delivery of large-scale nuclear projects, including more than a thousand lessons learned captured from Olkiluoto 3 and Flamanville 3 projects. This book of knowledge as well as the return of experience of AREVA's and EDF's teams are now being fully leveraged on ongoing projects, especially on Flamanville 3 and Taishan, and will be incorporated in all future EPRTM projects.

  9. Nuclear choice. Towards the EPR with mincing steps

    International Nuclear Information System (INIS)

    The French government is on the way to give its green light for the construction of the EPR (European Pressurized water Reactor), the 1600 MWe demonstrator reactor of third generation of Framatome ANP (Areva). Fifty seven months will be necessary for its construction which, with the public inquiry, would lead to a first commissioning by 2010. This reactor will progressively renew the present day park between 2015-2020. The EPR project will cost 3 billions of euros but the financing remains to be found. Short paper. (J.S.)

  10. Eficácia do sistema de contenção (automatizado e mecânico) no atordoamento de bovinos Effectiveness of the restraining system (automated and mechanical) in the cattle stunning

    OpenAIRE

    William Bertoloni; Douglas Andreolla

    2010-01-01

    Um total de 800 bovinos machos (nelore/anelorados), com idade entre 28 e 36 meses, foi atordoado com pistola pneumática, com pressão de operação de 11 a 12bar e haste de penetração de 15.9mm de diâmetro, em sistemas de contenção diferentes (mecânico e atomatizado). O box de contenção mecânico tradicional (2,53x0,88x2,20m) não permitiu a contenção da cabeça do animal; no segundo tratamento utilizou-se box de contenção automatizado (2,60x0,85x2,30m), com parede lateral e piso móveis, guilhotina...

  11. Herramientas de marketing de contenido para la generación de tráfico cualificado online

    Directory of Open Access Journals (Sweden)

    Fernando Toledano Cuervas-Mons

    2015-01-01

    Full Text Available El presente trabajo detalla las diferentes disciplinas de marketing orientadas a fomentar relaciones de confianza con la audiencia y constituir oportunidades de negocio en el ámbito digital. Las técnicas descritas están basadas en la generación o publicación de contenidos y su difusión a través de las redes sociales. Se analizan los tipos de tráfico web y se determina la metodología para realizar la comunicación de marca a través del contenido. Por último, se describen las etapas y procesos automatizados del marketing digital como también las plataformas tecnológicas utilizadas para conseguir convertir el tráfico web generado a través de contenidos.

  12. Nuclear choice. Towards the EPR with mincing steps; Choix nucleaire. L'EPR a petits pas

    Energy Technology Data Exchange (ETDEWEB)

    Jemain, A

    2003-10-01

    The French government is on the way to give its green light for the construction of the EPR (European Pressurized water Reactor), the 1600 MWe demonstrator reactor of third generation of Framatome ANP (Areva). Fifty seven months will be necessary for its construction which, with the public inquiry, would lead to a first commissioning by 2010. This reactor will progressively renew the present day park between 2015-2020. The EPR project will cost 3 billions of euros but the financing remains to be found. Short paper. (J.S.)

  13. Copenhagen vs Everett, Teleportation, and ER=EPR

    CERN Document Server

    Susskind, Leonard

    2016-01-01

    Quantum gravity may have as much to tell us about the foundations and interpretation of quantum mechanics as it does about gravity. The Copenhagen interpretation of quantum mechanics and Everett's Relative State Formulation are complementary descriptions which in a sense are dual to one another. My purpose here is to discuss this duality in the light of the of ER=EPR conjecture.

  14. Photochemical and free radicals study of cyanobacteria using EPR spectroscopy

    Czech Academy of Sciences Publication Activity Database

    Stopka, Pavel; Maršálek, B.; Křížová, Jana

    Brno, 2008. s. 6.19. ISBN 978-80-214-3715-9. [Meeting on Chemistry and Life /4./. 09.09.2008-11.09.2008, Brno] Institutional research plan: CEZ:AV0Z40320502 Keywords : EPR * ESR Subject RIV: CA - Inorganic Chemistry

  15. New ceramic EPR resonators with high dielectric permittivity

    Science.gov (United States)

    Golovina, Iryna; Geifman, Ilia; Belous, Anatolii

    2008-11-01

    New EPR resonators were developed by using a ceramic material with a high dielectric constant, ɛ = 160. The resonators have a high quality factor, Q = 10 3, and enhance the sensitivity of an EPR spectrometer up to 170 times. Some advantages of the new ceramic resonators are: (1) cheaper synthesis and simplified fabricating technology; (2) wider temperature range; and (3) ease of use. The ceramic material is produced with a titanate of complex oxides of rare-earth and alkaline metals, and has a perovskite type structure. The resonators were tested with X-band EPR spectrometers with cylindrical (TE 011) and rectangular (TE 102) cavities at 300 and 77 K. We discovered that EPR signal strength enhancement depends on the dielectric constant of the material, resonator geometry and the size of the sample. Also, an unusual resonant mode was found in the dielectric resonator-metallic cavity structure. In this mode, the directions of microwave magnetic fields of the coupled resonators are opposite and the resonant frequency of the structure is higher than the frequency of empty metallic cavity.

  16. EPR investigations of gamma-irradiated ground black pepper

    Science.gov (United States)

    Polovka, Martin; Brezová, Vlasta; Staško, Andrej; Mazúr, Milan; Suhaj, Milan; Šimko, Peter

    2006-02-01

    The γ-radiation treatment of ground black pepper samples resulted in the production of three paramagnetic species ( GI- GIII) which arise from a different origin and have different thermal behavior and stability. The axially symmetric spectra can be characterized by the spin Hamiltonian parameters: GI ( g⊥=2.0060, g∥=2.0032; A⊥=0.85 mT, A∥=0.70 mT) and GII ( g⊥=2.0060, g∥=2.0050; A⊥=0.50 mT, A∥=0.40 mT) assigned to carbohydrate radical structures. The parameters of EPR signal GIII ( g⊥=2.0029, g∥=2.0014; A⊥=3.00 mT, A∥=1.80 mT) possessed features characteristic of cellulose radical species. The activation energies, evaluated by Arrhenius analysis, are in order Ea( GI)EPR measurements performed 20 weeks after radiation process confirmed that a temperature increase from 298 to 353 K, caused a significant decrease of integral EPR signal intensity for γ-irradiated samples (˜40%), compared to the reference (non-irradiated) ground black pepper, where a decrease of ˜13% was found. The influence of γ-radiation treatment on the radical-scavenging activities of aqueous and ethanol extracts of black pepper were investigated by both an EPR spin trapping technique and DPPH assay. No changes were detected in either the water or ethanol extracts for a γ-irradiation dose of 10 kGy.

  17. A fast method for ionized food identification: EPR

    International Nuclear Information System (INIS)

    Electronic paramagnetic resonance allows the detection of ionized food only after dry storage, avoiding reaction of radicals with water. Dry and solid parts are used for analysis (bones for meat and fish, kernels for fruits). Dosimetry is possible by EPR spectrometry of alanine-L fixed on products treated in industrial irradiators

  18. EPR Imaging at a Few Megahertz Using SQUID Detectors

    Science.gov (United States)

    Hahn, Inseob; Day, Peter; Penanen, Konstantin; Eom, Byeong Ho

    2010-01-01

    An apparatus being developed for electron paramagnetic resonance (EPR) imaging operates in the resonance-frequency range of about 1 to 2 MHz well below the microwave frequencies used in conventional EPR. Until now, in order to obtain sufficient signal-to-noise radios (SNRs) in conventional EPR, it has been necessary to place both detectors and objects to be imaged inside resonant microwave cavities. EPR imaging has much in common with magnetic resonance imaging (MRI), which is described briefly in the immediately preceding article. In EPR imaging as in MRI, one applies a magnetic pulse to make magnetic moments (in this case, of electrons) precess in an applied magnetic field having a known gradient. The magnetic moments precess at a resonance frequency proportional to the strength of the local magnetic field. One detects the decaying resonance-frequency magnetic- field component associated with the precession. Position is encoded by use of the known relationship between the resonance frequency and the position dependence of the magnetic field. EPR imaging has recently been recognized as an important tool for non-invasive, in vivo imaging of free radicals and reduction/oxidization metabolism. However, for in vivo EPR imaging of humans and large animals, the conventional approach is not suitable because (1) it is difficult to design and construct resonant cavities large enough and having the required shapes; (2) motion, including respiration and heartbeat, can alter the resonance frequency; and (3) most microwave energy is absorbed in the first few centimeters of tissue depth, thereby potentially endangering the subject and making it impossible to obtain adequate signal strength for imaging at greater depth. To obtain greater penetration depth, prevent injury to the subject, and avoid the difficulties associated with resonant cavities, it is necessary to use lower resonance frequencies. An additional advantage of using lower resonance frequencies is that one can use

  19. EPR/PTFE dosimetry for test reactor environments

    Energy Technology Data Exchange (ETDEWEB)

    Vehar, D.W.; Griffin, P.J.; Quirk, T.J. [Sandia National Laboratories, Albuquerque, NM 87185-1146 (United States)

    2011-07-01

    The use of Electron Paramagnetic Resonance (EPR) spectroscopy with materials such as alanine is well established as a technique for measurement of ionizing radiation absorbed dose in photon and electron fields such as Co-60, high-energy bremsstrahlung and electron-beam fields [1]. In fact, EPR/Alanine dosimetry has become a routine transfer standard for national standards bodies such as NIST and NPL. In 1992 the Radiation Metrology Laboratory (RML) at Sandia National Laboratories implemented EPR/Alanine capabilities for use in routine and calibration activities at its Co-60 and pulsed-power facilities. At that time it also investigated the usefulness of the system for measurement of absorbed dose in the mixed neutron/photon environments of reactors such as the Sandia Pulsed Reactor and the Annular Core Research Reactor used for hardness testing of electronics. The RML concluded that the neutron response of alanine was a sufficiently high fraction of the overall dosimeter response that the resulting uncertainties in the photon dose would be unacceptably large for silicon-device testing. However, it also suggested that non-hydrogenous materials such as polytetrafluoroethylene (PTFE) would exhibit smaller neutron response and might be useful in mixed environments. Preliminary research with PTFE in photon environments indicated considerable promise, but further development was not pursued at that time. Because of renewed interest in absorbed dose measurements that could better define the individual contributions of photon and neutron components to the overall dose delivered to a test object, the RML has re-initiated the development of an EPR/PTFE dosimetry system. This effort consists of three stages: 1) Identification of PTFE materials that may be suitable for dosimetry applications. It was speculated that the inconsistency of EPR signatures in the earlier samples may have been due to variability in PTFE manufacturing processes. 2) Characterization of dosimetry in

  20. EPR/PTFE dosimetry for test reactor environments

    International Nuclear Information System (INIS)

    The use of Electron Paramagnetic Resonance (EPR) spectroscopy with materials such as alanine is well established as a technique for measurement of ionizing radiation absorbed dose in photon and electron fields such as Co-60, high-energy bremsstrahlung and electron-beam fields [1]. In fact, EPR/Alanine dosimetry has become a routine transfer standard for national standards bodies such as NIST and NPL. In 1992 the Radiation Metrology Laboratory (RML) at Sandia National Laboratories implemented EPR/Alanine capabilities for use in routine and calibration activities at its Co-60 and pulsed-power facilities. At that time it also investigated the usefulness of the system for measurement of absorbed dose in the mixed neutron/photon environments of reactors such as the Sandia Pulsed Reactor and the Annular Core Research Reactor used for hardness testing of electronics. The RML concluded that the neutron response of alanine was a sufficiently high fraction of the overall dosimeter response that the resulting uncertainties in the photon dose would be unacceptably large for silicon-device testing. However, it also suggested that non-hydrogenous materials such as polytetrafluoroethylene (PTFE) would exhibit smaller neutron response and might be useful in mixed environments. Preliminary research with PTFE in photon environments indicated considerable promise, but further development was not pursued at that time. Because of renewed interest in absorbed dose measurements that could better define the individual contributions of photon and neutron components to the overall dose delivered to a test object, the RML has re-initiated the development of an EPR/PTFE dosimetry system. This effort consists of three stages: 1) Identification of PTFE materials that may be suitable for dosimetry applications. It was speculated that the inconsistency of EPR signatures in the earlier samples may have been due to variability in PTFE manufacturing processes. 2) Characterization of dosimetry in

  1. Stability of cellulose radicals produced by radiation in spices as studied by the EPR spectroscopy

    International Nuclear Information System (INIS)

    The results are presented of EPR measurements on the stability of cellulose radicals produced in 26 popular spices irradiated with a dose of 7 kGy of gamma rays. EPR measurements were done with the use of an EPR spectrometer EPR-10 MINI at X band (microwave radiation of frequency 9.5 GHz), produced by St. Petersburg Instruments Ltd. The aim of the work was to prove the applicability of the EPR method for the control of irradiation in the investigated spices. (author)

  2. Analysis of variability in kinematic parameters during the execution of a succession of pirouettes in dance through an experimental protocol Análisis de la variabilidad de parámetros cinemáticos durante la ejecución de una sucesión de piruetas en danza a través de un protocolo automatizado

    Directory of Open Access Journals (Sweden)

    F. J. Moreno

    2010-09-01

    bailarina. Se filmó la separación de los pies antes de iniciar cada pirueta cuyo ritmo de ejecución era marcado por un metrónomo electrónico. Los datos provenientes de los distintos aparatos de medida  nos aportaron información acerca de la mayor o menor precisión temporal de los sujetos y de la consistencia en la ejecución del movimiento de los mismos a diferentes ritmos de ejecución. Los resultados mostraron una mayor precisión temporal conforme el ritmo de ejecución aumentaba, así como una mayor precisión temporal del grupo de bailarinas con mayor experiencia. En conclusión, el protocolo automatizado aplicado es útil para analizar la variabilidad de parámetros cinemáticos durante la ejecución de una sucesión de piruetas en danza.
    Palabras Clave: Protocolo experimental, variabilidad, piruetas en danza, precisión temporal, nivel de experiencia.

  3. EPR researches of tree cuts for estimating radio - ecological situation

    International Nuclear Information System (INIS)

    Full text: The basic aim of present work is to study a possibility of nature object application, in this case the annual rings of trees, for reveal of the effects of post - radiation action for them by EPR method. The cuts of poplars at the age 70 years and older grown in various regions of Kazakhstan with increased level of radiation background were selected as the research objects. EPR spectra were registered for every annual ring separately at the room temperatures. On the basis of EPR experimental results it was ascertained that the EPR spectra of annual rings may be symbolically divided for two groups every of which is possessed of its own definite kind of the spectrum. The first group are the spectra of the annual rings relating to 1981 - 1999 years (in 1999 the trees were cut), and the second group are these of the rings relating 1934 - 1980 years. At that it has been showed that an additional exposure to γ-ray of Co60 transforms the first group spectrum to the form typical for the second group, i.e. the radiation effect becomes apparent in these experiments. The analyses of EPR spectra parameters has been performed and a correlation between the dependences of intensity of certain components in the spectrum on gamma - irradiation dose and the age of the annul rings has been showed. One can suppose that the intensity changing of these spectrum components in the second group, concerned with free radical accumulation, was the results of long-term action to the object by ionizing radiations. The studied effects can be used for average estimation of absorbed doses of ionizing radiation by environment objects, in particular, by residents of regions surveyed

  4. Chemistry of artemisinin: an EPR study and nucleobases interaction

    International Nuclear Information System (INIS)

    In the present, the radical transformations of artemisinin, a potent antimalarial drug have been examined using EPR and EPR spin trapping techniques. The effect of light on artemisinin has been investigated at 77 K as well as with the use of phenyl butyl nitrone (PBN) spin trapping agent. While no EPR signal was observed at 77 K, intense light irradiation of artemisinin/PBN gave EPR signal characteristic of radical transformation of the PBN. The reactions of artemisinin with iron (II), manganese (II), hemin and ferrocyanide ion have been investigated by spin trapping techniques. Artemisinin/iron (II) formed spin adducts with nitrosobenzene, nitroso-t-butane and PBN. The hypertine splittings of the spin adducts were aN=1.08 mT/aN=1.25 mT/aN=0.09 mT and aN=1.56 mT/aN=0.29 mT respectively. PBN trapping of artemether/iron (II) gave similar result to artemisinin/iron (II). These results are indicative of secondary carbon-centered radical formation. While artemisinin/hemin/PBN gave very weak EPR signal, ferrocyanide under the same condition gave no signal. Incubation of artemisinin with RNA at different reaction conditions, including irradiation with light, heat and mild acidic media, revealed no RNA damage when examined by agarose electrophoresis. However, artemisinin/iron (II) caused RNA damage in pH-dependant manner. In contrast, hemin did not show the same effect when it was used instead of iron (II). (Author)

  5. Multifrequency EPR study on freeze-dried fruits before and after X-ray irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Yordanov, N.D. [Laboratory EPR, Institute of Catalysis, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria)]. E-mail: ndyepr@bas.bg; Aleksieva, K. [Laboratory EPR, Institute of Catalysis, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria); Dimitrova, A. [Laboratory EPR, Institute of Catalysis, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria); Georgieva, L. [Institute of Cryobiology and Food Technologies, 1162 Sofia (Bulgaria); Tzvetkova, E. [Institute of Cryobiology and Food Technologies, 1162 Sofia (Bulgaria)

    2006-09-15

    X-, K- and Q-band EPR studies on lyophilized whole pulp parts of blue plum, apricot, peach, melon as well as achens and pulp separately of strawberry before and after X-ray irradiation are reported. Before irradiation all samples show in X band a weak singlet EPR line with g=2.0030+/-0.0005, except melon, which is EPR silent. Immediately after irradiation all samples exhibit complex fruit-depending spectra, which decay with time and change to give, in ca. 50days, an asymmetric singlet EPR line with g=2.0041+/-0.0005. Only apricot pulp gave a typical ''sugar-like'' EPR spectrum. Singlet EPR lines recorded after irradiation in X -band are K- and Q-band resolved as typical anisotropic EPR spectra with g{sub ||}=2.0023+/-0.0003 and g{sub -}bar =2.0041+/-0.0005. In addition, K- and Q-band EPR spectra of all samples show a superposition with the six EPR lines of Mn{sup 2+} naturally present in the fruits. The saturation behavior of the EPR spectra of achens of lyophilized and fresh strawberry is also studied. The differences in g factors of samples before and after X-ray irradiation might be used for the identification of radiation processing of fruits in the case of pulp and the differences in the EPR saturation behavior might be used for the achens of strawberry.

  6. Echo detected EPR as a tool for detecting radiation-induced defect signals in pottery

    Energy Technology Data Exchange (ETDEWEB)

    Zoleo, Alfonso, E-mail: alfonso.zoleo@unipd.it [Department of Chemical Sciences, University of Padova, via Marzolo 1, I-35131 Padova (Italy); Bortolussi, Claudia, E-mail: claudia.bortolussi@studenti.unipd.it [Department of Chemical Sciences, University of Padova, via Marzolo 1, I-35131 Padova (Italy); Brustolon, Marina, E-mail: marinarosa.brustolon@unipd.it [Department of Chemical Sciences, University of Padova, via Marzolo 1, I-35131 Padova (Italy)

    2011-08-15

    Archaeological fragments of pottery have been investigated by using CW-EPR and Echo Detected EPR (EDEPR). EDEPR allows to remove the CW-EPR dominant Fe(III) background spectrum, hiding much weaker signals potentially useful for dating purpose. EDEPR spectra attributed to a methyl radical and to feldspar defects have been recorded at room and low temperature for an Iron Age cooking ware (700 B.C.). A study on the dependence of EDEPR intensity over absorbed dose on a series of {gamma}-irradiated brick samples (estimated age of 562 {+-} 140 B.C.) has confirmed the potential efficacy of the proposed method for spotting defect signals out of the strong iron background. - Highlights: > Fe(III) CW-EPR signals cover CW-EPR-detectable defects in ceramics. > Echo detected EPR gets rid of Fe(III) signals, disclosing defect signals. > Echo detected EPR detects defect signals even at relatively low doses.

  7. Dental enamel, as a solid EPR sensor of radiation

    International Nuclear Information System (INIS)

    Full text: In a previous report, concerning the use of EPR Dosimetry applied to Radiological Emergencies, we discussed the extraction, quality control and use of Dental Enamel, as a solid sensor for 66 keV X-ray radiation, from 376(6)mGy up to 1139(17)mGy; the dose given as kerma in air. The irradiation gives rise to carbonate radicals in this material, whose number increases monotonically with dose. Using EPR Spectroscopy, the radical in the lattice is identified, and the increase in number with dose measured from the peak to peak amplitude, hpp, of the (single) spectral line. The results that we obtained motivated us to follow that work, increasing the dose by repeated irradiations, in a period of 18 months, up to 2626mGy. The EPR data,[hpp/mg], can be fitted with a linear equation: Dose(Gy)=0.04(0.04)+0.0615(0.0015)·[hpp/mg], the value of Dose measured with a calibrated ionization chamber associated to the irradiator arrangement. No degradation of the EPR spectral line was observed in this 18 months period. That stability in storing data, and the rate value of (62±2) mGy/[hpp/mg], opens the possibility for creating epidemiologic data bases for dose below a few Gy. Further, we compared data measured both by Biodosimetry and by EPR Dosimetry, by simultaneous irradiation of venous blood and tooth enamel samples. The dose value, given as before by the calibrated ionization chamber, is [0.75±0.01]Gy; Biodosimetry yields the mean value of dose as 0.65 Gy, between a minimum of 0.45 Gy and a maximum of 0.81 Gy, while from EPR Dosimetry data,·[hpp/mg], and the above mentioned linear fit, we obtain the value [0.82±0.06]Gy. Those results make relevant further measurements and analysis of the limits of each of the dosimetric methods that we considered in this work. Those facts motivated us to search for a method to replicate dental enamel, with the expectation of improving its characteristics as an EPR solid sensor, in ranges of dose below 5 Gy. We succeeded in

  8. Biossensor para deteção do antigénio específico da próstata

    OpenAIRE

    Oliveira, Nélia Maria Pinto de

    2011-01-01

    O antigénio específico da próstata (PSA) é um valioso biomarcador tumoral sendo útil no rastreio, diagnóstico, estadiamento e monitorização do carcinoma da próstata. Para a determinação deste antigénio, os biossensores surgem como uma técnica muito atrativa devido à sua simplicidade, portabilidade, rápida e sensível análise em tempo real quando comparados com as técnicas convencionais dos equipamentos automatizados. Neste estudo, foi desenvolvido um imunossensor eletroquímico para a deteção d...

  9. Speech of B. Esteve 'EPR deployment shifting into high gear'

    International Nuclear Information System (INIS)

    Economics of nuclear power has been assessed by various European studies. Of particular interest in the Finnish study which supported the decision to build Finland's 5th nuclear power unit. Sensitivity studies, as well as the 2005 update of this study, demonstrate the robustness of nuclear competitiveness compared to other electricity generation means. EPR is AREVA's generation 3+ reactor: a large evolutionary power reactor with improved safety. EPR is being built at the Finnish site of Olkiluoto. It is being launched in France at Flamanville and it is licensed in the USA in view of its deployment on that market. It has also been offered to China in response to the Generation 3 international invitation to bid

  10. EPR of divalent manganese in non-Kramers hosts

    International Nuclear Information System (INIS)

    Various interactions which lead to the observation of sharp EPR spectra of the high half-integer spin impurity Mn2+ (S=5/2) in paramagnetic hosts with integer spins S=1 and S=2 have been studied. Studies have been carried out on the basis of data extracted from experimental EPR spectra of Mn2+ in single crystal of divalent nickel Ni2+ (S=1) and Fe2+ (S=1) perchlorate hexahydrates. It has been shown that dipolar host-host and host-guest couplings broaden resonance lines of Mn2+. Narrowing of the lines in the both crystals can be mainly attributed to the host-guest exchange interactions and quenching of the host spins

  11. On the computer simulation of the EPR-Bohm experiment

    International Nuclear Information System (INIS)

    We argue that supraluminal correlation without supraluminal signaling is a necessary consequence of any finite and discrete model for physics. Every day, the commercial and military practice of using encrypted communication based on correlated, pseudo-random signals illustrates this possibility. All that is needed are two levels of computational complexity which preclude using a smaller system to detect departures from ''randomness'' in the larger system. Hence the experimental realizations of the EPR-Bohm experiment leave open the question of whether the world of experience is ''random'' or pseudo-random. The latter possibility could be demonstrated experimentally if a complexity parameter related to the arm length and switching time in an Aspect-type realization of the EPR-Bohm experiment is sufficiently small compared to the number of reliable total counts which can be obtained in practice. 6 refs

  12. The Chernobyl accident: EPR dosimetry on dental enamel of children

    International Nuclear Information System (INIS)

    The radiation dose on tooth enamel of children living close to Chernobyl has been evaluated by EPR. The sample preparation was reduced to a minimum of mechanical steps to remove a piece of enamel. A standard X-ray tube at low energy was used for additive irradiation. The filtration effect of facial soft tissue was taken into account. The radiation dose for a group of teeth slightly exceeds the annual dose, whereas for another group the dose very much exceeds the annual dose. Since the higher dose is found in teeth whose enamel have much lower EPR sensitivity to the radiation, it can be suggested that for these teeth the native signal could alter the evaluation of the smaller radiation signal

  13. Total loss of AC power analysis for EPR reactor

    Energy Technology Data Exchange (ETDEWEB)

    Darnowski, Piotr, E-mail: piotr.darnowski@itc.pw.edu.pl [Warsaw University of Technology, Institute of Heat Engineering, Nowowiejska 21/25, 00-665 Warsaw (Poland); Skrzypek, Eleonora, E-mail: eleonora.skrzypek@ncbj.gov.pl [Warsaw University of Technology, Institute of Heat Engineering, Nowowiejska 21/25, 00-665 Warsaw (Poland); National Centre for Nuclear Research (NCBJ), A. Sołtana 7, 05-400 Otwock-Świerk (Poland); Mazgaj, Piotr, E-mail: piotr.mazgaj@itc.pw.edu.pl [Warsaw University of Technology, Institute of Heat Engineering, Nowowiejska 21/25, 00-665 Warsaw (Poland); Świrski, Konrad [Warsaw University of Technology, Institute of Heat Engineering, Nowowiejska 21/25, 00-665 Warsaw (Poland); Gandrille, Pascal [AREVA NP SAS, Tour AREVA, 1 place Jean Millier, 92084 Paris La Défense (France)

    2015-08-15

    Highlights: • Total loss of AC power (Station Blackout) was simulated for the EPR reactor model. • In-vessel phase of the accident is under consideration. • Comparison of MELCOR and MAAP results is presented. • MELCOR and MAAP results are comparable. - Abstract: In this paper the results of severe accident simulations for the EPR reactor in the case of loss of offsite power combined with total failure of all diesel generators (total loss of AC power) are presented. Calculations were performed with MELCOR 2.1 computer code for in-vessel phase of the accident. In this scenario, the unavailability of all offsite and onsite power sources and the lack of cooling leads directly to core degradation, material relocation to the lower plenum and rupture of the reactor pressure vessel. MELCOR results were compared qualitatively and quantitatively with MAAP4 code results and show a good agreement.

  14. Tooth enamel EPR dosimetry: sources of errors and their correction

    Energy Technology Data Exchange (ETDEWEB)

    Ivannikov, A.I.; Skvortsov, V.G.; Stepanenko, V.F.; Tsyb, A.F.; Khamidova, L.G.; Tikunov, D.D

    2000-05-15

    Some of the most important sources of systematic errors in dose determination using tooth enamel EPR spectroscopy and ways of reducing those errors are discussed. Enamel from the outside of the front teeth should not be used for dose determination because of induction of paramagnetic centers by solar light. The accuracy of the method in the low dose range is limited by variation in the shape of the EPR signal of unirradiated enamel, which can be described by an initial intrinsic signal and which varies for different samples with standard deviation of 20-30 mGy. The energy dependence of enamel sensitivity should be taken into account in the form of a correction factor. The value of this factor is estimated at 1.1-1.3 for real radiation fields in radiation contaminated territories. Variation in enamel sensitivity for different samples is shown to be within limits of 10-15% of the average value.

  15. Kinetic Measurements Using EPR Imaging with a Modulated Field Gradient

    Science.gov (United States)

    Herrling, Thomas; Fuchs, Jürgen; Groth, Norbert

    2002-01-01

    EPR imaging with modulated field gradient was applied for the investigation of fast diffusion processes. Three different imaging methods are possible: spectral-temporal, spatio-temporal, and spectral-spatial imaging. The time resolution is on the order of seconds and the spatial resolution is in the micrometer region. The efficiency of this imaging technique is demonstrated for the penetration of the spin probe Tempol in the skin of hairless mice biopsies. The skin is normally protected against the penetration of water soluble substances by the horny layer, a resistive thin lipophilic layer. Overcoming this horny layer for water soluble ingredients is one of the main practical problems for the topical application of pharmaceutics which could be investigated by EPR imaging. Different images represent the penetration behavior of the water soluble Tempol in the skin after treatment with the penetration enhancer DMSO (Dimethylsulfoxide) and after removing the horny layer.

  16. The EPR-a comprehensive design concept against external events

    International Nuclear Information System (INIS)

    The main objective of design provisions against external hazards is to ensure that the safety functions required to bring the plant to safe shutdown are not inadmissibly affected by any external hazards that might be postulated for the intended site of the plant. In the design of the European Pressurized Water Reactor (EPR) particular attention was paid to external hazards such as earthquake, airplane crash, and explosion pressure wave. The standard EPR covers a large range of possible site conditions, the design earthquake enveloping safe shutdown earthquakes (SSE) to be expected for potential sites. The loads for the design basis airplane crash and - if required - for the design extension airplane crash as well as for external Explosion Pressure Wave are defined depending on site specific requirements. Protection against other external load cases such as extreme winds and external flooding is also included in the standard design

  17. EPR becomes reality at Finland's Olkiluoto 3

    Energy Technology Data Exchange (ETDEWEB)

    Gueldner, R.; Giese, U

    2005-07-01

    The EPR is a third-generation pressurized water reactor (PWR). Its development was started in 1992 by Framatome and Siemens within a Franco-German partnership. Since 2001 this work has been continued by Framatome ANP, which was formed when the two companies merged their nuclear businesses. The French company AREVA, world market leader in nuclear technology, holds a 66% share in Framatome ANP, with Siemens owning 34%. From the very start, development of the EPR was focused on improving plant safety and economics even further. The new reactor development was jointly financed together with the leading power utilities of both countries. The first steps towards realization of an EPR nuclear power plant were taken at Olkiluoto, Finland in 2004, consisting of initial preparation of the construction site. By mid-February 2005 the local municipality - Eurajoki - had issued a construction permit, and the Finnish Government a construction license pursuant to the Finnish Nuclear Energy Act. This had been preceded by a preliminary safety assessment prepared by the Finnish Radiation and Nuclear Safety Authority (STUK) for the Finnish Ministry of Trade and Industry in which STUK verified that it did not see any safety-related issues opposing issuance of the nuclear construction license. STUK emphasized that the evolutionary design of the EPR had been further improved by AREVA compared to the previous product lines. Concreting work began this spring and the unit will start commercial operation in 2009. Construction of an EPR has also been given the political go-ahead in France. According to the utility Electricite de France (EDF) the new reactor will be built as a forerunner of a later series at the site of Flamanville in Normandy. Construction is scheduled to begin in 2007. An EPR nuclear power plant has a rated electric capacity of around 1600 MW, depending on specific site conditions. Being the product of intense bilateral cooperation the EPR combines the technological

  18. Establishing EPR-channels between Nanomechanics and Atomic Ensembles

    OpenAIRE

    Hammerer, K.; Aspelmeyer, M.; Polzik, E. S.; Zoller, P.

    2008-01-01

    We suggest to interface nanomechanical systems via an optical quantum bus to atomic ensembles, for which means of high precision state preparation, manipulation and measurement are available. This allows in particular for a Quantum Non-Demolition Bell measurement, projecting the coupled system, atomic ensemble - nanomechanical resonator, into an entangled EPR-state. The entanglement is observable even for nanoresonators initially well above their ground states and can be utilized for teleport...

  19. EPR dosimetric properties of nano-barium sulfate

    International Nuclear Information System (INIS)

    Nano/micro BaSO4 were prepared through the co-precipitation method to measure ionizing radiation doses using electron paramagnetic resonance (EPR). The nano-BaSO4 sample was characterized using X-ray diffraction (XRD), and transmission electron microscopy (TEM) techniques. The dose response and fading properties of nano- and micro-phase BaSO4 were compared in EPR spectra. The prepared nano- and micro-BaSO4 samples have the same hole and electron centers, which may be attributed to SO4− and SO3−, respectively. The dosimetric signals for prepared nano- and micro-BaSO4 have spectroscopic splitting factor (g) with values 2.0025±0.0006 and 2.0027±0.0006, respectively. The nanocrystalline sample has a linear γ-ray dose response over the range 0.4 Gy–1 kGy. The performance parameters which including detection limit and critical level calculated from weighted and unweighted least-squares fitting. The sensitivity of nano-BaSO4 to γ-ray is one and a half times more than alanine. The lifetime and activation energy for nano-BaSO4 were estimated by conducting a thermal stability study, and were 5.7±1.1×104 years and 0.73±0.14 eV, respectively. The combined and expanded uncertainties accompanying measurements were ±3.89% and ±7.78%, respectively. - Highlights: • Preparation of nano-BaSO4 using the co-precipitation method. • Study of the dosimetric properties of nano-barium sulfate using the EPR technique. • Comparison between a new EPR dosimeter using nano-materials and standard alanine. • Calculation of the uncertainty budget for nano-BaSO4

  20. EPR = ER, scattering amplitude and entanglement entropy change

    Energy Technology Data Exchange (ETDEWEB)

    Seki, Shigenori, E-mail: sigenori@hanyang.ac.kr [Research Institute for Natural Science, Hanyang University, Seoul 133-791 (Korea, Republic of); Sin, Sang-Jin, E-mail: sjsin@hanyang.ac.kr [Department of Physics, Hanyang University, Seoul 133-791 (Korea, Republic of)

    2014-07-30

    We study the causal structure of the minimal surface of the four-gluon scattering, and find a world-sheet wormhole parametrized by Mandelstam variables, thereby demonstrate the EPR = ER relation for gluon scattering. We also propose that scattering amplitude is the change of the entanglement entropy by generalizing the holographic entanglement entropy of Ryu–Takayanagi to the case where two regions are divided in space–time.

  1. EPR studies of cooperative binding of Cu (II) to hemoglobin

    International Nuclear Information System (INIS)

    The investigation of the relative affinities of the two pairs of hemoglobin copper sites by monitoring the EPR spectra of the complexes formed by the reaction of copper with deoxyhemoglobin is reported. A model in which two sites are assumed to accept copper ions in a noncooperative way is not able to predict the experimental results. Thus it is conclude that the binding of these ions to hemoglobin is a cooperative phenomenon. (Author)

  2. EPR spectroscopy as a tool in homogeneous catalysis research

    OpenAIRE

    Goswami, M.; Chirila, A.; Rebreyend, C.; Bruin,, Henk

    2015-01-01

    In the context of homogeneous catalysis, open-shell systems are often quite challenging to characterize. Nuclear magnetic resonance (NMR) spectroscopy is the most frequently applied tool to characterize organometallic compounds, but NMR spectra are usually broad, difficult to interpret and often futile for the study of paramagnetic compounds. As such, electron paramagnetic resonance (EPR) has proven itself as a useful spectroscopic technique to characterize paramagnetic complexes and reactive...

  3. EPR investigations of gamma-irradiated ground black pepper

    Energy Technology Data Exchange (ETDEWEB)

    Polovka, Martin [Department of Chemical Technology of Wood, Pulp and Paper, Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinskeho 9, SK-812 37 Bratislava (Slovakia); Brezova, Vlasta [Department of Physical Chemistry, Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinskeho 9, SK-812 37 Bratislava (Slovakia)]. E-mail: vlasta.brezova@stuba.sk; Stasko, Andrej [Department of Physical Chemistry, Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinskeho 9, SK-812 37 Bratislava (Slovakia); Mazur, Milan [Department of Physical Chemistry, Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinskeho 9, SK-812 37 Bratislava (Slovakia); Suhaj, Milan [Food Research Institute, Priemyselna 4, P.O. Box 25, SK-824 75 Bratislava (Slovakia); Simko, Peter [Food Research Institute, Priemyselna 4, P.O. Box 25, SK-824 75 Bratislava (Slovakia)

    2006-02-15

    The {gamma}-radiation treatment of ground black pepper samples resulted in the production of three paramagnetic species (GI-GIII) which arise from a different origin and have different thermal behavior and stability. The axially symmetric spectra can be characterized by the spin Hamiltonian parameters: GI (g{sub -}bar =2.0060, g{sub -}bar =2.0032; A{sub -}bar =0.85mT, A{sub -}bar =0.70mT) and GII (g{sub -}bar =2.0060, g{sub -}bar =2.0050; A{sub -}bar =0.50mT, A{sub -}bar =0.40mT) assigned to carbohydrate radical structures. The parameters of EPR signal GIII (g{sub -}bar =2.0029, g{sub -}bar =2.0014; A{sub -}bar =3.00mT, A{sub -}bar =1.80mT) possessed features characteristic of cellulose radical species. The activation energies, evaluated by Arrhenius analysis, are in order E{sub a}(GI)EPR measurements performed 20 weeks after radiation process confirmed that a temperature increase from 298 to 353K, caused a significant decrease of integral EPR signal intensity for {gamma}-irradiated samples ({approx}40%), compared to the reference (non-irradiated) ground black pepper, where a decrease of {approx}13% was found. The influence of {gamma}-radiation treatment on the radical-scavenging activities of aqueous and ethanol extracts of black pepper were investigated by both an EPR spin trapping technique and DPPH assay. No changes were detected in either the water or ethanol extracts for a {gamma}-irradiation dose of 10kGy.

  4. DETECTION OF EPR USING A PULSED MICROWAVE ACOUSTIC TECHNIQUE

    OpenAIRE

    Netzelmann, U.; Lerchner, H.; Pelzl, J.; Sigrist, M.

    1983-01-01

    A new pulsed microwave acoustic method is shown to be suited for the detection of EPR. Pressure amplitudes obtained for DPPH in n-hexane agree with theoretical predictions. Our calculations clearly demonstrate that temperature gradients within the sample are important for generating large signal amplitudes. Hence this technique is of special interest for samples with an inhomogeneous distribution of paramagnetic centers or for the study of interfaces.

  5. EPR investigations of gamma-irradiated ground black pepper

    International Nuclear Information System (INIS)

    The γ-radiation treatment of ground black pepper samples resulted in the production of three paramagnetic species (GI-GIII) which arise from a different origin and have different thermal behavior and stability. The axially symmetric spectra can be characterized by the spin Hamiltonian parameters: GI (g-bar =2.0060, g-bar =2.0032; A-bar =0.85mT, A-bar =0.70mT) and GII (g-bar =2.0060, g-bar =2.0050; A-bar =0.50mT, A-bar =0.40mT) assigned to carbohydrate radical structures. The parameters of EPR signal GIII (g-bar =2.0029, g-bar =2.0014; A-bar =3.00mT, A-bar =1.80mT) possessed features characteristic of cellulose radical species. The activation energies, evaluated by Arrhenius analysis, are in order Ea(GI)a(GIII)a(GII). The EPR measurements performed 20 weeks after radiation process confirmed that a temperature increase from 298 to 353K, caused a significant decrease of integral EPR signal intensity for γ-irradiated samples (∼40%), compared to the reference (non-irradiated) ground black pepper, where a decrease of ∼13% was found. The influence of γ-radiation treatment on the radical-scavenging activities of aqueous and ethanol extracts of black pepper were investigated by both an EPR spin trapping technique and DPPH assay. No changes were detected in either the water or ethanol extracts for a γ-irradiation dose of 10kGy

  6. Public debate about the EPR nuclear power plant at Flamanville

    International Nuclear Information System (INIS)

    The project of building of he EPR reactor at Flamanville (Manche, France) has been submitted to the public debate. This document includes a presentation of the project and of the rules of the public debate, a synthesis of the file made by the prime contractor (EDF), a synthesis of the collective book of national actors concerned by the project (a group of associations for environment protection, Areva company, the ministries of economy and ecology, Global Chance, association of pro-nuclear ecologists (AEPN), 'Sortir du Nucleaire' (out-of nuclear) network, group of scientists for the information about nuclear (GSIEN), association for the promotion of the Flamanville site (Proflam), French nuclear energy society (SFEN) in association with 'Sauvons le Climat' (let's save climate), regional collective association 'EPR non merci, ni ailleurs, ni ici' (EPR, no thanks, neither elsewhere, nor here), NegaWatt), and 5 detailed books of actors: ACRO (association for the control of radioactivity in Western France), CFDT and CGT syndicates, the economic and social council of Basse Normandie region, and Proflam. (J.S.)

  7. TL, EPR and optical absorption in natural grossular crystal

    Energy Technology Data Exchange (ETDEWEB)

    Yauri, J.M. [Institute of Physics, University of Sao Paulo, Rua do Matao, Travessa R, 187, CEP 05508-900, Sao Paulo (Brazil); Department of Physics, University of San Agustin, Av. Independencia S/N, Arequipa (Peru); Cano, N.F. [Institute of Physics, University of Sao Paulo, Rua do Matao, Travessa R, 187, CEP 05508-900, Sao Paulo (Brazil)], E-mail: nilocano@dfn.if.usp.br; Watanabe, S. [Institute of Physics, University of Sao Paulo, Rua do Matao, Travessa R, 187, CEP 05508-900, Sao Paulo (Brazil)

    2008-10-15

    Grossular is one of six members of silicate Garnet group. Two samples GI and GII have been investigated concerning their luminescence thermally stimulated (TL). EPR and optical absorption and the measurements were carried out to find out whether or not same point defects are responsible for all three properties. Although X-rays diffraction analysis has shown that both GI and GII have practically the same crystal structure of a standard grossular crystal, they presented different behavior in many aspects. The TL glow curve shape, TL response to radiation dose, the effect of annealing at high temperatures before irradiation, the dependence of UV bleaching parameters on peak temperature, all of them differ going from GI to GII. The EPR signals around g=2.0 as well as at g=4.3 and 6.0 have much larger intensity in GI than in GII. Very high temperature (>800 deg. C) annealing causes large increase in the bulk background absorption in GI, however, only very little in GII. In the cases of EPR and optical absorption, the difference in their behavior can be attributed to Fe{sup 3+} ions; however, in the TL case one cannot and the cause was not found as yet.

  8. EPR investigation of some irradiated traditional oriental spices

    International Nuclear Information System (INIS)

    The X-band EPR spectra of unirradiated and 60 Co gamma ray irradiated cardamom (Elettaria cardamomum L. Maton, Zingiberaceae), ginger ((Zingiber officinale Rosc., Zingiberaceae), saffron (Crocus sativus L., Iridaceae), and curry have been investigated at room temperature. All unirradiated spices presented a weak resonance line with g-factors around free-electron ones, most probably due to the presence of semiquinones, previously reported to have paramagnetic properties. After gamma ray irradiation at absorbed dose up to 11.3 kGy we have noticed in all spices the presence of complex EPR spectra consisting of a superposition of at last two different paramagnetic species whose amplitude increase monotonously with the absorbed dose. A 100 deg. C isothermal annealing of 11.3 kGy irradiated samples has shown a differential reduction of amplitude of various components that form the initial spectra, but even after 5 h of thermal treatment, the remaining amplitude represents no less than 40% from the initial ones, testifying for a good thermal stability. The presences of initial EPR spectra as well as the remaining amplitude after isothermal annealing are very useful in identifying any irradiation treatment applied to this category of species. (authors)

  9. EPR investigation of some traditional oriental irradiated spices

    International Nuclear Information System (INIS)

    The 9.50 GHz electron paramagnetic resonance (EPR) spectra of unirradiated and 60Co γ-ray irradiated cardamom (Elettaria cardamomum L. Maton, Zingiberaceae), ginger ((Zingiber officinale Rosc., Zingiberaceae), and saffron (Crocus sativus L., Iridaceae) have been investigated at room temperature. All unirradiated spices presented a weak resonance line with g-factors around free-electron ones. After γ-ray irradiation at an absorbed dose of up to 11.3 kGy, the presence of EPR spectra whose amplitude increase monotonously with the absorbed dose has been noticed with all spices. A 100 oC isothermal annealing of 11.3 kGy irradiated samples has shown a differential reduction of amplitude of various components that compose initial spectra, but even after 3.6 h of thermal treatment, the remaining amplitude represents no less then 30% of the initial ones. The same peculiarities have been noticed after 83 days storage at room temperature but after 340 days storage at ambient conditions only irradiated ginger displays a weak signal that differs from those of unirradiated sample. All these factors could be taken into account in establishing at which extent the EPR is suitable to evidence any irradiation treatment applied to these spices

  10. EPR and magnetism of the nanostructured natural carbonaceous material shungite

    Science.gov (United States)

    Augustyniak-Jabłokow, Maria Aldona; Yablokov, Yurii V.; Andrzejewski, Bartłomiej; Kempiński, Wojciech; Łoś, Szymon; Tadyszak, Krzysztof; Yablokov, Mikhail Y.; Zhikharev, Valentin A.

    2010-04-01

    The X-band EPR and magnetic susceptibility in the temperature range 4.2-300 K study of the shungite-I, natural nanostructured material from the deposit of Shunga are reported. Obtained results allow us to assign the EPR signal to conduction electrons, estimate their number, N P, and evaluate the Pauli paramagnetism contribution to shungite susceptibility. A small occupation (~5%) of the localized nonbonding π states in the zigzag edges of the open-ended graphene-like layers and/or on σ ( sp 2+ x ) orbitals in the curved parts of the shungite globules has been also revealed. The observed temperature dependence of the EPR linewidth can be explained by the earlier considered interaction of conduction π electrons with local phonon modes associated with the vibration of peripheral carbon atoms of the open zigzag-type edges and with peripheral carbon atoms cross-linking different nanostructures. The relaxation time T 2 and diffusion time T D are found to have comparable values (2.84 × 10-8 and 1.73 × 10-8 s at 5.2 K, respectively), and similar dependence on temperature. The magnetic measurements have revealed the suppression of orbital diamagnetism due to small amount of large enough fragments of the graphene layers.

  11. EPR dose reconstruction for bone-seeking 90Sr

    International Nuclear Information System (INIS)

    The results of the EPR dose reconstruction in calcified tissues of dog injected with 90Sr are presented. It has been established that there is no essential difference in the values of doses absorbed in tooth tissues of teeth in symmetric positions in the mouth, whereas a significant difference occurs in the values of absorbed doses in teeth in non-symmetric positions. In the case of 90Sr internal exposure the dose reconstruction in crown dentine plays an important role. It has been found that its quantity is close to the dose in diaphyseal cortical bone of the femur, dose at the endosteal bone surface and in femural fatty marrow. The fact that these values exceed doses absorbed in tooth enamel points out the predominant contribution of internal exposure. The highest absorbed doses have been observed in metaphyseal trabecular femur bones, tooth alveolar bone walls, and cortical and trabecular vertebra that can be considered as suitable candidates for biomarkers of internal 90Sr exposure for post-mortal autopsy. The satisfactory correlation has been found between the doses reconstructed in calcified dog tissues and the doses measured by EPR in alanine dosimeters fixed in (or nearby) the sites of autopsy of bones/teeth. The experiments provide support for the view that EPR retrospective dosimetry with calcified tissues for internal exposure is unique in providing useful information on the doses obtained

  12. Tetrabromidocuprates(II)—Synthesis, Structure and EPR

    Science.gov (United States)

    Zabel, André; Winter, Alette; Kelling, Alexandra; Schilde, Uwe; Strauch, Peter

    2016-01-01

    Metal-containing ionic liquids (ILs) are of interest for a variety of technical applications, e.g., particle synthesis and materials with magnetic or thermochromic properties. In this paper we report the synthesis of, and two structures for, some new tetrabromidocuprates(II) with several “onium” cations in comparison to the results of electron paramagnetic resonance (EPR) spectroscopic analyses. The sterically demanding cations were used to separate the paramagnetic Cu(II) ions for EPR measurements. The EPR hyperfine structure in the spectra of these new compounds is not resolved, due to the line broadening resulting from magnetic exchange between the still-incomplete separated paramagnetic Cu(II) centres. For the majority of compounds, the principal g values (g‖ and g⊥) of the tensors could be determined and information on the structural changes in the [CuBr4]2− anions can be obtained. The complexes have high potential, e.g., as ionic liquids, as precursors for the synthesis of copper bromide particles, as catalytically active or paramagnetic ionic liquids. PMID:27104522

  13. Tetrachloridocuprates(II—Synthesis and Electron Paramagnetic Resonance (EPR Spectroscopy

    Directory of Open Access Journals (Sweden)

    Peter Strauch

    2012-02-01

    Full Text Available Ionic liquids (ILs on the basis of metal containing anions and/or cations are of interest for a variety of technical applications e.g., synthesis of particles, magnetic or thermochromic materials. We present the synthesis and the results of electron paramagnetic resonance (EPR spectroscopic analyses of a series of some new potential ionic liquids based on tetrachloridocuprates(II, [CuCl4]2−, with different sterically demanding cations: hexadecyltrimethylammonium 1, tetradecyltrimethylammonium 2, tetrabutylammonium 3 and benzyltriethylammonium 4. The cations in the new compounds were used to achieve a reasonable separation of the paramagnetic Cu(II ions for EPR spectroscopy. The EPR hyperfine structure was not resolved. This is due to the exchange broadening, resulting from still incomplete separation of the paramagnetic Cu(II centers. Nevertheless, the principal values of the electron Zeemann tensor (g║ and g┴ of the complexes could be determined. Even though the solid substances show slightly different colors, the UV/Vis spectra are nearly identical, indicating structural changes of the tetrachloridocuprate moieties between solid state and solution. The complexes have a promising potential e.g., as high temperature ionic liquids, as precursors for the formation of copper chloride particles or as catalytic paramagnetic ionic liquids.

  14. EPR investigation of some traditional oriental irradiated spices

    Energy Technology Data Exchange (ETDEWEB)

    Duliu, Octavian G. [University of Bucharest, Department of Atomic and Nuclear Physics, Magurele, C.P. MG-11, RO-077125 Bucharest (Romania)]. E-mail: duliu@pcnet.ro; Georgescu, Rodica [National Institute for Physics and Nuclear Engineering -Horia Hulubei, C.P. MG-6, RO-077125 Bucharest (Romania); Ali, Shaban Ibrahim [University of Bucharest, Department of Atomic and Nuclear Physics, Magurele, C.P. MG-11, RO-077125 Bucharest (Romania)

    2007-06-15

    The 9.50 GHz electron paramagnetic resonance (EPR) spectra of unirradiated and {sup 60}Co {gamma}-ray irradiated cardamom (Elettaria cardamomum L. Maton, Zingiberaceae), ginger ((Zingiber officinale Rosc., Zingiberaceae), and saffron (Crocus sativus L., Iridaceae) have been investigated at room temperature. All unirradiated spices presented a weak resonance line with g-factors around free-electron ones. After {gamma}-ray irradiation at an absorbed dose of up to 11.3 kGy, the presence of EPR spectra whose amplitude increase monotonously with the absorbed dose has been noticed with all spices. A 100 {sup o}C isothermal annealing of 11.3 kGy irradiated samples has shown a differential reduction of amplitude of various components that compose initial spectra, but even after 3.6 h of thermal treatment, the remaining amplitude represents no less then 30% of the initial ones. The same peculiarities have been noticed after 83 days storage at room temperature but after 340 days storage at ambient conditions only irradiated ginger displays a weak signal that differs from those of unirradiated sample. All these factors could be taken into account in establishing at which extent the EPR is suitable to evidence any irradiation treatment applied to these spices.

  15. EPR investigation of some traditional oriental irradiated spices

    Science.gov (United States)

    Duliu, Octavian G.; Georgescu, Rodica; Ali, Shaban Ibrahim

    2007-06-01

    The 9.50 GHz electron paramagnetic resonance (EPR) spectra of unirradiated and 60Co γ-ray irradiated cardamom ( Elettaria cardamomum L. Maton, Zingiberaceae), ginger (( Zingiber officinale Rosc., Zingiberaceae), and saffron ( Crocus sativus L., Iridaceae) have been investigated at room temperature. All unirradiated spices presented a weak resonance line with g-factors around free-electron ones. After γ-ray irradiation at an absorbed dose of up to 11.3 kGy, the presence of EPR spectra whose amplitude increase monotonously with the absorbed dose has been noticed with all spices. A 100 °C isothermal annealing of 11.3 kGy irradiated samples has shown a differential reduction of amplitude of various components that compose initial spectra, but even after 3.6 h of thermal treatment, the remaining amplitude represents no less then 30% of the initial ones. The same peculiarities have been noticed after 83 days storage at room temperature but after 340 days storage at ambient conditions only irradiated ginger displays a weak signal that differs from those of unirradiated sample. All these factors could be taken into account in establishing at which extent the EPR is suitable to evidence any irradiation treatment applied to these spices.

  16. Peptide-membrane Interactions by Spin-labeling EPR

    Science.gov (United States)

    Smirnova, Tatyana I.; Smirnov, Alex I.

    2016-01-01

    Site-directed spin labeling (SDSL) in combination with Electron Paramagnetic Resonance (EPR) spectroscopy is a well-established method that has recently grown in popularity as an experimental technique, with multiple applications in protein and peptide science. The growth is driven by development of labeling strategies, as well as by considerable technical advances in the field, that are paralleled by an increased availability of EPR instrumentation. While the method requires an introduction of a paramagnetic probe at a well-defined position in a peptide sequence, it has been shown to be minimally destructive to the peptide structure and energetics of the peptide-membrane interactions. In this chapter, we describe basic approaches for using SDSL EPR spectroscopy to study interactions between small peptides and biological membranes or membrane mimetic systems. We focus on experimental approaches to quantify peptide-membrane binding, topology of bound peptides, and characterize peptide aggregation. Sample preparation protocols including spin-labeling methods and preparation of membrane mimetic systems are also described. PMID:26477253

  17. The application of EPR dosimetry for radiotherapy and radiation protection

    Energy Technology Data Exchange (ETDEWEB)

    Kudynski, R. (Calgary Univ., AB (Canada). Dept. of Medical Physics); Kudynska, J.; Buckmaster, H.A. (Calgary Univ., AB (Canada). Dept. of Physics and Astronomy)

    1993-06-01

    This paper reports the first clinical trial of the application of the continuous wave electron paramagnetic resonance (CW-EPR) spectrum of alanine to determine the radiation dose received by a patient. The results of these measurements are compared with those obtained using thermoluminescent dosimetry (TLD) simultaneously. The 9 GHz EPR measurements were made at 13[sup o]C. The time stability of the radiation induced radicals in alanine was confirmed. The fractionated radiation doses received in the clinical trial were determined from a calibration curve (linear regression coefficient r = 0.9995) obtained by irradiating L-alanine samples with 60-800 cGy doses using cobalt 60 gamma rays obtained from an Eldorado 8 Cobalt 60 unit at a rate of [approx] 60 cGy/min. It is shown that the absorbed dose in tissue-equivalent material can be determined using EPR spectroscopy with an accuracy of [approx] 3% at low dose levels (60 cGy) whereas the error using TLD is [approx] 5% and that this method of dose determination is preferable to the present TLD method because it is simpler and more accurate. (author).

  18. Characterization of beer flavour stability (EPR - spin trapping)

    International Nuclear Information System (INIS)

    The beer flavour stability is coupled with free radical degradation processes. Probably, aldehydes produced during the brewery but also generated by stalling are responsible for beer flavour as well as for its breaking down. The storing beer at the lower temperatures and in the dark place inhibits, and otherwise the rising temperature and illumination accelerate the rate of such radical processes. Beers contain naturally occurring radical scavengers - antioxidants which inhibit such unwanted reactions. Then depleting of scavengers results in the breaking down of the beer stability. EPR spin trapping technique was used as monitor such processes and for characterising so the flavour stability of beer. The probe was temperated at 60 grad C in the cavity of EPR spectrometer in the presence of spin trapping agent, N-tert.-butyl-α-phenyl nitrone (PBN) and EPR spectra were recorded for few hours. After beer antioxidants become depleted, free radicals formed by the beer degradation are scavenged by PBN spin trap and this point is characterised with a dramatically increased concentration of the free radicals trapped

  19. Assessment of an alanine EPR dosimetry technique with enhanced precision and accuracy

    CERN Document Server

    Hayes, R B; Wieser, A; Romanyukha, A A; Hardy, B L; Barrus, J K

    2000-01-01

    Dose reconstruction in the course of a series of blind tests demonstrated that an accuracy of 10 mGy for low doses and 1% for high doses can be achieved using EPR spectroscopy. This was accomplished using a combination of methodologies including polynomial filtration of the EPR spectrum, dosimeter rotation during scanning, use of an EPR standard fixed into the resonator and subtraction of all nonradiogenic signals. Doses were reconstructed over the range of 0.01-1000 Gy using this compound spectral EPR analysis. This EPR technique, being equally applicable to fractionated doses (such as those delivered during multiple radiotherapy treatments), was verified to exhibit dose reciprocity. Irradiated alanine dosimeters which were stored exhibited compound spectral EPR signal fading of ca 3% over 9 months. All error estimates given in this paper are given at the 1 standard deviation level and unless otherwise specified do not account for uncertainties in source calibration.

  20. EPR study of sagitta otoliths of Sciaenidae fish

    International Nuclear Information System (INIS)

    Full text. Otoliths are crystalline structures of calcium carbonate (CaCO3) located in the inner ear of bone fish that are responsible for balance maintenance in the water column and sense of direction. The bio mineralization of these structures occurs during the fish development; when the otolith growth layers are formed. In this work, electron paramagnetic resonance (EPR) spectroscopy is applied to study the sagitta otoliths via manganese (Mn2+) spectra, since in calcium carbonates the Mn2+ ion is a natural substitutional impurity at Ca2+ sites. The sagitta otoliths of the Sciaenidae fish Paralonchurus brasiliensis, commonly known as cabeca dura (47 samples), and Stellifer rastrifer, known as cangoa (22 samples), were obtained from specimens captured in coastal areas of Rio de Janeiro State, southeastern Brazil: Atafona (21 deg 37'S), Farol de Sao Tome (22 deg 05'S) and Rio das Ostras (22 deg 30'S). EPR spectra of sagitta otoliths were obtained in X-band (9GHz) at room temperature. The EPR spectra are typical of Mn2+ in aragonite powder, associated to an occupation of Ca2+ site with nine nearest neighbor oxygen atoms. It is well established in the literature that the otolith core is constituted by calcite, which is covered by aragonite during the fish growth. However, otoliths of younger fishes showed similar EPR spectra when compared to the older ones, indicating that aragonite is the main bio mineral structure in both maturity stages. In a previous work, these two Sciaenidae species presented significant differences in sagitta otoliths shape, which were related to environmental differences (e.g. water temperature, nutrients, depth) among the sampling sites (Atafona, Farol de Sao Tome and Rio das Ostras). Meanwhile, we do not observed differences in the EPR spectra, indicating that the aragonite crystallization process and the occupation of manganese are not related with the environment where these fish species are living. Then, we can infer that the sagitta

  1. EPR study of sagitta otoliths of Sciaenidae fish

    Energy Technology Data Exchange (ETDEWEB)

    Beneditto, Ana Paula Madeira di; Franco, Roberto Weider de Assis [Universidade Estadual do Norte Fluminense (UENF), RJ (Brazil)

    2011-07-01

    Full text. Otoliths are crystalline structures of calcium carbonate (CaCO{sub 3}) located in the inner ear of bone fish that are responsible for balance maintenance in the water column and sense of direction. The bio mineralization of these structures occurs during the fish development; when the otolith growth layers are formed. In this work, electron paramagnetic resonance (EPR) spectroscopy is applied to study the sagitta otoliths via manganese (Mn{sup 2+}) spectra, since in calcium carbonates the Mn{sup 2+} ion is a natural substitutional impurity at Ca{sup 2+} sites. The sagitta otoliths of the Sciaenidae fish Paralonchurus brasiliensis, commonly known as cabeca dura (47 samples), and Stellifer rastrifer, known as cangoa (22 samples), were obtained from specimens captured in coastal areas of Rio de Janeiro State, southeastern Brazil: Atafona (21 deg 37'S), Farol de Sao Tome (22 deg 05'S) and Rio das Ostras (22 deg 30'S). EPR spectra of sagitta otoliths were obtained in X-band (9GHz) at room temperature. The EPR spectra are typical of Mn{sup 2+} in aragonite powder, associated to an occupation of Ca{sup 2+} site with nine nearest neighbor oxygen atoms. It is well established in the literature that the otolith core is constituted by calcite, which is covered by aragonite during the fish growth. However, otoliths of younger fishes showed similar EPR spectra when compared to the older ones, indicating that aragonite is the main bio mineral structure in both maturity stages. In a previous work, these two Sciaenidae species presented significant differences in sagitta otoliths shape, which were related to environmental differences (e.g. water temperature, nutrients, depth) among the sampling sites (Atafona, Farol de Sao Tome and Rio das Ostras). Meanwhile, we do not observed differences in the EPR spectra, indicating that the aragonite crystallization process and the occupation of manganese are not related with the environment where these fish species

  2. EPR 蒸汽发生器制造技术%Manufacture Technology of the EPR Steam Generator

    Institute of Scientific and Technical Information of China (English)

    景军涛; 江才林; 罗吾希; 郑晨

    2013-01-01

    根据欧洲第三代先进压水堆型( EPR)核电蒸汽发生器的制造过程中积累的经验,并结合其他压水堆型核电蒸汽发生器的制造经验,介绍了EPR蒸汽发生器的结构特点,并分别对制造过程中的一些关键制造技术,如管板一次侧面堆焊、管板深孔钻、内套筒的装配和水室封头的制造等进行详细阐述,为后续压水堆型核电蒸汽发生器的制造提供经验参考。%According to the manufacture experience of evolutionary power reactor ( EPR) steam generator ( third generation reactor type ) and combining with the manufacture experience other pressurized water reactor(PWR) steam generator,the structure characteristic of EPR steam generator was introduced .Some key technology during EPR steam generator manufacture , such as tubesheet primary side cladding , tubesheet deep drilling , installation of the bundle wrapper , manufacture of the channel head and so on were also introduced .It provides some reference for manufacturing the PWR steam generator .

  3. Public debate about the EPR nuclear power plant at Flamanville; Debat public sur la centrale nucleaire EPR a Flamanville

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    The project of building of he EPR reactor at Flamanville (Manche, France) has been submitted to the public debate. This document includes a presentation of the project and of the rules of the public debate, a synthesis of the file made by the prime contractor (EDF), a synthesis of the collective book of national actors concerned by the project (a group of associations for environment protection, Areva company, the ministries of economy and ecology, Global Chance, association of pro-nuclear ecologists (AEPN), 'Sortir du Nucleaire' (out-of nuclear) network, group of scientists for the information about nuclear (GSIEN), association for the promotion of the Flamanville site (Proflam), French nuclear energy society (SFEN) in association with 'Sauvons le Climat' (let's save climate), regional collective association 'EPR non merci, ni ailleurs, ni ici' (EPR, no thanks, neither elsewhere, nor here), NegaWatt), and 5 detailed books of actors: ACRO (association for the control of radioactivity in Western France), CFDT and CGT syndicates, the economic and social council of Basse Normandie region, and Proflam. (J.S.)

  4. Review of nuclear power international (NPI) future strategy. The European pressurized water reactor - EPR

    International Nuclear Information System (INIS)

    An international collaboration of French and German industrial concerns and utilities has developed a design for the European Pressurized Water Reactor (EPR), drawing on their combined experience in reactor design, construction and operation. The technical and safety features of the EPR are reviewed, including containment and confinement functions and the ''nuclear island'' concept. The EPR advantages of competitiveness, safety and public acceptance are seen as key to the revival of the fortunes of the nuclear power industry. (UK)

  5. The effect of aging on EPR cable electrical performance during LOCA simulations

    International Nuclear Information System (INIS)

    When exposed to a LOCA environment, some EPR cable materials experience substantial moisture absorption and dimensional changes. These phenomena may contribute to mechanical damage of the cable insulation resulting in electrical degradation. Recent experiments illustrate that the extent of moisture absorption and dimensional changes during an accident simulation are dependent on the EPR product, the ''accelerated age'', and the aging technique employed to achieve that age. Results for several commercial EPR materials are summarized. 4 tabls. 6 figs.

  6. A Regional PD Strategy for EPR Systems: Evidence-Based IT Development

    DEFF Research Database (Denmark)

    Simonsen, Jesper; Hertzum, Morten

    2006-01-01

    One of the five regions in Denmark has initiated a remark-able and alternative strategy for the development of Elec-tronic Patient Record (EPR) systems. This strategy is driven by Participatory Design (PD) experiments and based on evidence of positive effects on the clinical practice when using EPR...... systems. We present this PD strategy and our related research on evidence-based IT development. We report from a newly completed PD experiment with EPR in the region conducted through a close collaboration compris-ing a neurological stroke unit, the region’s EPR unit, the vendor, as well as the authors....

  7. CW EPR and 9 GHz EPR imaging investigation of stable paramagnetic species and their antioxidant activities in dry shiitake mushroom (Lentinus edodes).

    Science.gov (United States)

    Nakagawa, Kouichi; Hara, Hideyuki

    2016-05-01

    We investigated the antioxidant activities and locations of stable paramagnetic species in dry (or drying) shiitake mushroom (Lentinus edodes) using continuous wave (CW) electron paramagnetic resonance (EPR) and 9 GHz EPR imaging. CW 9 GHz EPR detected paramagnetic species (peak-to-peak linewidth (ΔHpp) = 0.57 mT) in the mushroom. Two-dimensional imaging of the sharp line using a 9 GHz EPR imager showed that the species were located in the cap and shortened stem portions of the mushroom. No other location of the species was found in the mushroom. However, radical locations and concentrations varied along the cap of the mushroom. The 9 GHz EPR imaging determined the exact location of stable paramagnetic species in the shiitake mushroom. Distilled water extracts of the pigmented cap surface and the inner cap of the mushroom showed similar antioxidant activities that reduced an aqueous solution of 0.1 mM 4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl. The present results suggest that the antioxidant activities of the edible mushroom extracts are much weaker than those of ascorbic acid. Thus, CW EPR and EPR imaging revealed the location and distribution of stable paramagnetic species and the antioxidant activities in the shiitake mushroom for the first time. PMID:26846304

  8. Monitoramento topográfico em tempo-real com a utilização de um sistema semi-automatizado

    OpenAIRE

    Miranda, Fabiani das Dores Abati

    2013-01-01

    Resumo: O monitoramento de estruturas por meio de técnicas geodésicas tem como finalidade a determinação de coordenadas de pontos em diferentes épocas, servindo assim, como subsidio a diversos profissionais para o estudo e acompanhamento do comportamento do objeto monitorado, discretizado por estes pontos. Isto é feito não somente após problemas ou colapsos, mas também como um procedimento rotineiro, voltado para este acompanhamento. Tendo em vista a importância do tema, buscam-se novas metod...

  9. X- and Q-band EPR studies on fine powders of irradiated plants. New approach for detection of their radiation history by using Q-band EPR spectrometry

    International Nuclear Information System (INIS)

    X- and Q-band EPR studies after γ-irradiation of some dry spices and aromatic herbs are reported. Before irradiation all samples show only one singlet line in X-band EPR, whereas the Q-band EPR spectrum of the same samples is a superposition of two individual spectra--one corresponding to the above EPR signal, with an anisotropic spectrum, and a second one consisting of six lines due to the Mn2+ naturally present in plants. The radiation induced EPR signal due to cellulose free radicals was not detected after γ-irradiation, but only the increase of the natural signal present before the irradiation. The fading kinetic of this EPR signal was monitored in three cases--when samples were kept in plastic bags without any special conditioning after irradiation, when samples were covered with paraffin before irradiation and when samples were dried at 60 deg. C for 1 h before irradiation. The studies show that stability of radiation induced EPR signals decreases in the order of: paraffin covered > heated before irradiation > kept at room conditions. The two EPR spectra in the Q-band--one with radiation dependent intensity and a second due to Mn2+, which is radiation independent allow identification of previous radiation treatment based on the fact that Mn2+ quantity in the sample is constant whereas the quantity of radiation-induced free radicals is temperature dependent. It was found that for irradiated samples the ratio between EPR intensity of the free radicals and that of Mn2+ before and after heating decreases with 50-60% whereas for non-irradiated samples it is ca. 10-15%

  10. Control de gestión para procesos de apoyo hoteleros

    Directory of Open Access Journals (Sweden)

    María Alejandra Ferrer

    2004-01-01

    Full Text Available Con base en el análisis de propuestas sobre indicadores para el control de gestión hotelera y la búsqueda empírica respecto a su aplicación en hoteles de máxima categoría ubicados en Maracaibo (Venezuela, se sistematizan los indicadores pertinentes para las gerencias de mantenimiento, seguridad, recursos humanos, sistemas y control financiero. En la experiencia de los hoteles predominan indicadores financieros tradicionales de eficiencia y oportunidad; éstos son complementados con el aporte de los autores estudiados y por las autoras con otras medidas de eficiencia y calidad. Además del control presupuestario, se destaca el uso de indicadores expresados en unidades físicas, tomando al huésped como cliente primario. Los índices hoteleros resultantes pueden ser adaptables a organizaciones similares, de acuerdo a su naturaleza, a los cambios internos y en el entorno, los cuales exigen flexibilidad y capacidad de adaptación. A pesar del uso de sistemas automatizados para el control de los procesos básicos en los hoteles, existen limitaciones tecnológicas para la recopilación y sistematización de información relativa a los procesos de apoyo.

  11. Protocol for emergency dosimetry based on phaners using EPR spectrometry

    International Nuclear Information System (INIS)

    In the case of a radiological accident due to an external overexposure involving a limited number of persons from the public or workers without dosemeters, dosimetry by Electronic Paramagnetic Resonance (EPR) spectrometry on tooth enamel, among other techniques such as biological dosimetry, can be an efficient tool. However, for an accident involving a large number of victims, most of dosimetric techniques are limited by the necessary short delay of the answer. Indeed, in this specific case, it is very important in a first time and as quick as possible to sort population according to the severity of the exposure and, in a second time, to assess the dose more accurately, especially for the most irradiated victims in order to define the best therapeutic strategy. As a matter of fact, EPR dosimetry on tooth enamel due to the invasive sampling cannot be used for emergency dosimetry. Nevertheless, EPR dosimetry on materials easily sampled on the victims or in their vicinity may be a pertinent tool. In this context, the objective of this work was to study the dosimetric properties of phaners and to provide operational guidelines describing the sampling, the storage conditions, the sample preparation and the EPR signal measurement for fast triage of population and dose assessment.We studied the dosimetric properties of fingernails and different types of hair. After having optimized the recording parameters, the analysis of EPR signal was carried out according to specific criteria, such as anisotropy, temporal fading, influence of external parameters and dose response.The important fading of the radio-induced signal may be diminished with an appropriate storage at low temperature, allowing measurements up to several weeks after irradiation. The signal intensity was found linear with the received dose at least until 50 Gy for studied materials. Detection limits were respectively estimated equal to 2 Gy f or fingernails and about 3 Gy for hairs. Concerning hair, a strong

  12. EPR meets the next generation PWR safety requirements

    International Nuclear Information System (INIS)

    At the origin was the common decision in 1989 of Framatome and Siemens to cooperate to design a Nuclear Island which meets the future needs of utilities. EDF and a group of main German Utilities joined this effort in 1991 and from that point were completely involved in the progress of the work. Compliance of the EPR with the European Utility Requirements (EUR) was verified to ensure a large acceptability of the design by other participating utilities. In addition, the entire process was backed up to the end of 1998 by the French and the German Safety Authorities which engaged into a long-lasting cooperation to define common requirements applicable to future Nuclear Power Plants. Upon signature of the Olkiluoto 3 contract, STUK, the Finnish safety and radiation authority, began reviewing the design of the EPR. Upon the favorable recommendation of STUK, the Finnish government delivered a Construction License for the Olkiluoto 3 NPP on February 17, 2005. Following the positive conclusion of the political debate in France with regard to nuclear energy, EDF will also submit a request to start the construction of an EPR on the Flamanville site. In the US, the first steps in view of a Design Certification by the NRC have been taken. These three independent decisions make the EPR the leading first generation 3+ design under construction. Important safety functions are assured by separate systems in a straightforward operating mode. Four separate, redundant trains for all safety systems are installed in four separate layout division for which a strict separation is ensured so that common mode failure, for example due to internal hazards, can be ruled out. A reduction in common mode failure potential is also obtained by design rules ensuring the systematic application of functional diversity. A four train-redundancy for the major safety systems provides flexibility in adapting the design to maintenance requirements, thus contributing to reduce the outage duration. Additional

  13. EPR oximetry of tumors in vivo in cancer therapy

    Science.gov (United States)

    Šentjurc, Marjeta; Čemažar, Maja; Serša, Gregor

    2004-05-01

    The partial oxygen pressure ( pO 2) in tumors is considered to be one of important factors that affect the response of tumors to different treatment. Therefore, we anticipate that the information about the variation of oxygen concentration in tumors can be used as a guide for individualizing radiotherapy, chemotherapy, and especially the combined therapies. There is thus a need to obtain quantitative data on the effects of different therapies on tumor oxygenation under in vivo conditions. One of the methods, which enable these measurements is EPR oximetry. In this work basic principles of the method will be described as well as some examples of tumor oxygenation changes after application of chemotherapeutic drugs (vinblastine, cisplatin, bleomycin) or electric pulses in combination with cisplatin or bleomycin to fibrosarcoma SA-1 tumors in mice. A paramagnetic probe, a char of Bubinga tree, was implanted into the tumor (center and periphery) and in the muscle or subcutis. EPR spectra line-width, which is proportional to oxygen concentration, was measured with time after the treatments. Tumor oxygenation was reduced for 58% of pretreatment value 1 h after intraperitoneal injection of 2.5 mg kg -1 VLB and returned to pretreatment level within 24 h. Reduction in oxygenation of muscle and subcutis was much smaller and returned to pretreatment value faster as in tumors. With cisplatin (4 mg kg -1) and bleomicyn (1 mg kg -1) the reduction was less than 15%, but increases in combined therapy to 70%. Similar reduction was observed also with electric pulses alone (eight pulses, 1300 V cm -1, 100 μs, 1 Hz) with fast recovery of 8 h. After electrochemotherapy the recovery was slower and occurs only after 48 h. This study demonstrates that EPR oximetry is a sensitive method for monitoring changes in tissue oxygenation after different treatments, which may have implications in controlling side effects of therapy and in the planning of combined treatments.

  14. EPR-a blend of national design types

    International Nuclear Information System (INIS)

    The good and bad experience gained from the construction and operation of more than 70 nuclear power stations in France and Germany played a part in the design of the European Pressurised Water Reactor. It is, however, rather more than a simple 'cross' between the French type N 4 reactor and the German Konvoi type. Additional requirements for even greater safety, higher utilisation factors and, first and foremost, even cheaper generation costs, had to be fulfilled. Development of the EPR is now virtually complete. The result is a type of reactor which, by virtue of the prompt involvement of the licensing authorities, the technical safety committees and electricity supply companies in both countries, has every chance, within a few years, of replacing the existing pressurised water reactors virtually throught Europe. Economy of operation has been improved once again by an increase of 15% in the output, amongst other things. This increase has been achieved at no additional expense. At present, there remains just a small disadvantage in relation to gas-fired GuD installations. If, however, gas prices were to rise from their current all-time-low level, this handicap would soon be overcome. EDF is to decide in the middle of the year whether and when it will build the first EPR installation. It would obviously be in Germany's interests if German electricity supply companies and German panel builders were to be involved. Otherwise, the capital of some 350 million DM which they and Germany have invested in the development of the EPR will have gone to waste. (orig.)

  15. The possible use of EPR spectroscopy for paint pigment identification

    International Nuclear Information System (INIS)

    Full text: Visible and near-infra-red reflectance spectroscopy are now routinely used for the identification of paint pigments in Renaissance painting, thus playing a part in authentication and restoration. Since most of the pigments are minerals, and many minerals either contain traces of paramagnetic ions, or have paramagnetic ions in their main components (e.g., chromic oxide, haematite), it seemed logical to determine whether EPR could distinguish between different pigments. 14 pigments of different colours were tested in a Varian E-12 EPR spectrometer, at a frequency of ∼ 9.1 GHz. Measurements were made at room (∼ 20 deg C) and liquid N2 temperatures, in the standard special quartz sample tubes. The active volume is 0. 15 ml, but at most, a volume of sample (powder) one tenth of this was used. The spectra (to be shown) clearly demonstrate that EPR can distinguish between different pigments. The power was 1 milliwatt, the modulation amplitude 4 gauss, the total field sweep 10,000 gauss, centred 5000 gauss and the amplification between 102 and 104, as indicated on the charts. The signal to noise ratio is excellent, and sensitivity could be increased (if necessary) by a factor of ∼ 103, thus allowing much smaller samples to be tested. Because the signals are so strong it should be possible to scan at least small painted canvases by the following non-destructive technique, using existing equipment. All that is required is a modified resonant cavity; it must have a high Q, and a slot where the magnetic field is maximum, and the electric field zero. The canvas can thus be placed flush with the waveguide, to interact with the microwave magnetic field emanating from the slot

  16. EPR dosimetry of radiation background in the Urals region

    Energy Technology Data Exchange (ETDEWEB)

    Shishkina, E.A.; Degteva, M.O.; Shved, V.A. [Urals Research Center for Radiation Medicine, 48-A Vorovsky, Chelyabinsk 454076 (Russian Federation); Fattibene, P.; Onori, S. [Istituto Superiore di Sanita and Istituto Nazionale di Fisica Nucleare (Italy); Wieser, A. [GSF, Forschungszentrum fuer Umwelt und Gesundheit, Ingolstaedter Landstr (Germany); Ivanov, D.V.; Bayankin, S.N. [Institute of Metal Physics, Russian Academy of Sciences (Russian Federation); Knyazev, V.A.; Vasilenko, E.I.; Gorelov, M. [ZAO, Closed Corporation ' Company GEOSPETSECOLOGIA' (Russian Federation)

    2006-07-01

    Method of Electron Paramagnetic Resonance is extensively applied to individual retrospective dosimetry. The background dose is unavoidable component of cumulative absorbed dose in the tooth enamel accumulated during the lifetime of donor. Estimation of incidental radiation dose using tooth enamel needs in extraction of background dose. Moreover, the variation of background doses in the population is a limited factor for reliable detection of additional irradiation especially for low dose level. Therefore the accurate knowledge of the natural background radiation dose is a critical element of EPR studies of exposed populations. In the Urals region the method applies for such two large cohorts as the workers of Mayak (Ozersk citizens) and Techa River riverside inhabitants (rural population). Current study aimed to investigate the Urals radiation background detected by EPR spectrometry. For this aim two group of unexposed Urals residents were separated, viz: citizens of Ozersk and rural inhabitants of Chelyabinsk region. Comparison of two investigated territories has demonstrated that from the point of view of radiation background it is impossible to assume the Urals population as uniform. The reliable difference between the urban and rural residents has been found. The average background doses of Ozersk donors is in average 50 mGy higher than those detected for rural residents. The individual variability of background doses for Osersk has been higher than in the rural results. The difference in background dose levels between two population results in different limits of accidental dose detection and individualization. The doses for 'Mayak' workers (Ozyorsk citizens) can be classed as anthropogenic if the EPR measurements exceed 120 mGy for teeth younger than 40 years, and 240 mGy for teeth older than 70 years. The anthropogenic doses for Techa River residents (rural population) would be higher than 95 mGy for teeth younger than 50 years and 270 mGy for

  17. Food quality assesment by using the EPR spin trapping technique

    International Nuclear Information System (INIS)

    Full text: The staling of food is a major problem in several food related industries. The loss of food full flavor is caused by a free radical process that is both oxygen and temperature dependent. The result is the degradation of large biomolecules to the smaller aldehydes, ketones and alcohols, that give rancid foods their characteristic foul odor and flavor. The free radicals responsible for these processes are short-lived and spin traps are used to increase the ability to detect them. The spin trap reacts with free radicals to form spin adducts which are also free radicals, but they are more stable than the original radical, a characteristic which allows their measurement by using EPR. In this paper we present the results obtained in characterizing free radical formation in vegetable oils and beer using a common spin trap N-tert--butylphenyl nitrone (PBN). PBN was added to either beer or vegetable oils and the samples were heated for several hours at 500 deg. C or exposed to UV radiation, in order to accelerate the free radical oxidation process. EPR spectra were recorded at different time intervals in order to follow the dynamics of the spin adducts formation. Typical spin adduct EPR spectra, similar to those reported in the literature, were obtained. In the case of beer, spin adduct formation occurs after a lag time during which the free radical formation is quenched by endogenous antioxidants, thus the value of this lag time is used to asses the beer shelf life, as it strongly correlates with the time required for a sensory panel to detect the characteristic cardboard off-flavor. The quantitative analysis revealed also the role of exogenous antioxidants in the kinetics of spin adduct formation for both beer and vegetable oils. (authors)

  18. EPR dosimetry of radiation background in the Urals region

    International Nuclear Information System (INIS)

    Method of Electron Paramagnetic Resonance is extensively applied to individual retrospective dosimetry. The background dose is unavoidable component of cumulative absorbed dose in the tooth enamel accumulated during the lifetime of donor. Estimation of incidental radiation dose using tooth enamel needs in extraction of background dose. Moreover, the variation of background doses in the population is a limited factor for reliable detection of additional irradiation especially for low dose level. Therefore the accurate knowledge of the natural background radiation dose is a critical element of EPR studies of exposed populations. In the Urals region the method applies for such two large cohorts as the workers of Mayak (Ozersk citizens) and Techa River riverside inhabitants (rural population). Current study aimed to investigate the Urals radiation background detected by EPR spectrometry. For this aim two group of unexposed Urals residents were separated, viz: citizens of Ozersk and rural inhabitants of Chelyabinsk region. Comparison of two investigated territories has demonstrated that from the point of view of radiation background it is impossible to assume the Urals population as uniform. The reliable difference between the urban and rural residents has been found. The average background doses of Ozersk donors is in average 50 mGy higher than those detected for rural residents. The individual variability of background doses for Osersk has been higher than in the rural results. The difference in background dose levels between two population results in different limits of accidental dose detection and individualization. The doses for 'Mayak' workers (Ozyorsk citizens) can be classed as anthropogenic if the EPR measurements exceed 120 mGy for teeth younger than 40 years, and 240 mGy for teeth older than 70 years. The anthropogenic doses for Techa River residents (rural population) would be higher than 95 mGy for teeth younger than 50 years and 270 mGy for teeth older

  19. Native and short-life signals in dentine EPR spectrum

    International Nuclear Information System (INIS)

    In this paper two aspects of dentine based dosimetry are investigated, namely the comparison of dentine and enamel native signal and the stability of the EPR spectrum after irradiation. Native signal intensity of dentine and enamel was found to be of the same order of the magnitude, suggesting that the origin of the native signal is not completely related to the total amount of organic component. Post-irradiation short life signals, with half-life of approximately 10 h, were observed. These signals are similar to those observed shortly after irradiation in enamel and after mechanical treatment in dentine

  20. Native and short-life signals in dentine EPR spectrum

    Energy Technology Data Exchange (ETDEWEB)

    Onori, S.; De Coste, V. [Istituto Superiore di Sanita, Department of Technology and Health, and Istituto Nazionale di Fisica, Nucleare, Rome (Italy); Fattibene, P. [Istituto Superiore di Sanita, Department of Technology and Health, and Istituto Nazionale di Fisica, Nucleare, Rome (Italy)], E-mail: paola.fattibene@iss.it; La Civita, S. [Istituto Superiore di Sanita, Department of Technology and Health, and Istituto Nazionale di Fisica, Nucleare, Rome (Italy)

    2008-02-15

    In this paper two aspects of dentine based dosimetry are investigated, namely the comparison of dentine and enamel native signal and the stability of the EPR spectrum after irradiation. Native signal intensity of dentine and enamel was found to be of the same order of the magnitude, suggesting that the origin of the native signal is not completely related to the total amount of organic component. Post-irradiation short life signals, with half-life of approximately 10 h, were observed. These signals are similar to those observed shortly after irradiation in enamel and after mechanical treatment in dentine.

  1. EPR investigation of antioxidant characteristics of some irradiated natural extracts

    International Nuclear Information System (INIS)

    The aim of the present work is to study the antioxidant characteristics of some irradiated natural extracts, like white Seaberry (Hippophae Rhamnoides) and Spirulina (Spirulina Platensis) using EPR (Electron Paramagnetic Resonance) spectroscopy technique. The methods used in this research concern the utilization of stable free radicals from nitrone classes, like nitroxide radical Tempol (2,2,6,6-tetramethyl-4-hydroxypiperidine-oxyl) and spin trap PBN (N-t-Butyl- a- phenylnitrone). The purpose is to see which are the changes induced in antioxidant activity by irradiation process, depending on irradiation absorbed doses. For low adsorbed doses an increasing of antioxidant activity for all studied samples was observed. (authors)

  2. Structured Reporting Method for ePR Generation

    OpenAIRE

    Arash Ebrahimi

    2007-01-01

    Appropriate electronic medical report-making soft-wares help physicians to personally generate records for paper printing and ePR access. Flat data-sheets with check-boxes that have been already used in traditional medical paper reports, do not satisfy today's physician demands for more professional reports."nAlternatively, Structured Reporting (SR) as the modified version of flat check-box based reporting method is being selected. In this method, items are nested in a hieratical tr...

  3. Pulsed EPR and ENDOR study of SiC nanopowders

    Czech Academy of Sciences Publication Activity Database

    Savchenko, Dariia

    Warsaw : Polish Academy of Sciences, 2014, s. 1063-1065. ISSN 0587-4246. [International School and Conference on the Physics of Semiconductors /43./. Wisla (PL), 07.06.2014-12.06.2014] R&D Projects: GA ČR GP13-06697P; GA MŠk(CZ) LM2011029 Grant ostatní: SAFMAT(XE) CZ.2.16/3.1.00/22132 Institutional support: RVO:68378271 Keywords : EPR * ENDOR * SiC nanopowders * size effect Subject RIV: BM - Solid Matter Physics ; Magnetism

  4. EPR nuclear plants: reliability at the service of innovation

    International Nuclear Information System (INIS)

    This document highlights Vinci's know-how in the field of nuclear power plant construction, and more particularly for EPR nuclear plant construction. It highlights the expertise of this group in advanced technology construction and civil engineering, its presence all over the world, its expertise in liners, concrete and prestressed concrete, its use of CAD and structure modelling software, its ability to joint complex projects, its ability to intervene during maintenance, dismantlement or other specific activities. It outlines its commitment for quality, security and protection of the environment

  5. An EPR Experiment for the Undergraduate Physical Chemistry Laboratory

    Science.gov (United States)

    Butera, R. A.; Waldeck, D. H.

    2000-11-01

    An experiment that illustrates the principles of electron paramagnetic resonance spectroscopy in the undergraduate physical chemistry laboratory is described. Students measure the value of g for DPPH and use it to determine the value of g for two inorganic complexes, Cu(acac)2 and VO(acac)2. The students use two instruments: an instructional device that illustrates the principles of EPR and a commercial Varian E4 spectrometer. This approach allows an elucidation of the principles of the method and provides experience with a more sophisticated research-grade instrument.

  6. Solution-phase EPR studies of single-walled carbon nanotubes

    Science.gov (United States)

    Chen, Y.; Chen, J.; Hu, H.; Hamon, M. A.; Itkis, M. E.; Haddon, R. C.

    1999-01-01

    We report EPR studies on pristine, purified, shortened and soluble SWNTs in various solution phases. Some of these samples give rise to strong, sharp EPR signals, and this technique is useful for monitoring the presence of SWNTs in aqueous and organic solvents. The soluble SWNTs carry about 1 unpaired electron per 10000 carbon atoms and give a free electron g-value.

  7. EPR and X-ray diffraction investigation of some Greek marbles and limestones

    International Nuclear Information System (INIS)

    Twelve different marble and limestone samples collected from well-known Greek quarries have been investigated by X-ray diffraction and electron paramagnetic resonance (EPR). X-ray diffraction spectra permitted to determine both major (calcite and dolomite) and minor (quartz or magnesite) mineralogical components. EPR has been used to investigate the same samples unirradiated and after 10 kGy gamma-ray irradiation. The unirradiated samples display typical EPR spectra of Mn2+ in calcite and dolomite as well as a superposition of these while some samples displayed EPR free radicals signals of centers (low field signal) and centers (high field signal). From X-ray diffraction and EPR spectra it was possible to extract numerical values of several numerical parameters such as dolomite to calcite ratio, EPR intensity parameter, and low field to high field EPR signals intensity ratio. These values as well as the correlation coefficients between the digital functions that described the low field Mn2+ ions EPR line have been used as entry data for cluster analysis to quantify the resemblance and differences between analyzed samples. (authors)

  8. Structure and dynamics of paramagnetic transients by pulsed EPR and NMR detection of nuclear resonance

    International Nuclear Information System (INIS)

    Structure and dynamics of transient radicals in pulse radiolysis can be studied by time resolved EPR and NMR techniques. EPR study of kinetics and relaxation is illustrated. The NMR detection of nuclear resonance in transient radicals is a new method which allows the study of hyperfine coupling, population dynamics, radical kinetics, and reaction mechanism. 9 figures

  9. Symmetry determination of commensurate and incommensurate phases of K2SeO4 by EPR

    International Nuclear Information System (INIS)

    From a reinterpretation of previously reported EPR results on γ-irradiated K2SeO4 crystals, the space group symmetry for commensurate (ferroelectric) phase of K2SeO4 is determined to be Pna21. The EPR results support the modulation of polarization as the reason for disappearance of ferroelectricity in incommensurate phase. (author)

  10. Error in assessing the absorbed dose from the EPR signal from dental enamel

    International Nuclear Information System (INIS)

    Dose measurements from EPR signals from dental enamel were analyzed in a random sampling of 100 teeth extracted in liquidators of the Chernobyl accident aftermath and the EPR spectra of dental enamel of 80 intact teeth from children studied. The mean square deviation of enamel sensitivity to ionizing radiation in some teeth is approximately 0.3 of the mean sensitivity value. The variability of the nature EPR spectrum of dental enamel limits in principle the lower threshold of EPR-measured 60 mGy doses. When assessing the individual absorbed doses from the EPR signal from dental enamel without additional exposure it is necessary to bear in mind the extra error of approximately 6-% at a confidence probability P=0.95 caused by the variability of enamel sensitivity to radiation in some teeth. This additional error may be ruled out by graduated additional exposure of the examined enamel samples

  11. Radiation chemistry of L-Alanine: application to EPR dosimetry (1)

    International Nuclear Information System (INIS)

    High energy ionizing radiation leaves stable radicals to certain organic materials, such as alanine and tartrate. Electron Paramagnetic Resonance (EPR) spectroscopy is a powerful tool for the identification and quantification of these radiation-induced radicals. An EPR method has been applied to study the radical characteristics of L-alanine after gamma radiation dose in the range of ∼mGy to 60 kGy. The free radicals induced by gamma radiation were fairly stable, and EPR intensity, radical concentration, was proportional to the absorbed dose up to 60 kGy. From the results of our EPR measurements, it can be concluded that an alanine/EPR method is a useful technique for gamma radiation dosimetry from very low to high dose range

  12. Double-stacked dielectric resonator for sensitive EPR measurements.

    Science.gov (United States)

    Jaworski, M; Sienkiewicz, A; Scholes, C P

    1997-01-01

    A new approximate method for predicting the resonant frequencies and for solving the field distribution problem of a cylindrical dielectric resonator (DR) is developed. The model proposed in this paper bridges the gap between rigorous and accurate finite-element or Green function-based numerical methods on the one hand and on the other hand, simple approximate solutions in which the field distribution can be described analytically, but the resulting frequency is accurate within a few percent only. In the method described here, the approximate solution for the microwave field distribution is modified by substituting different values of the radial separation constants inside and outside of the diskshaped DR. The model is generalized for the double-stacked DR structure and enables one to introduce corrections that take into account the presence of the shielding walls and of the cylindrical sample hole. Good agreement is found between experimental and calculated results for both the single and double-stacked structures that are designed around commercially available X-band DRs (9-10 GHz). For the resonant frequency of the lowest transverse-electric TEzero1 delta mode that is commonly used for EPR measurements, the accuracy of the method is better than 1%. Experimentally measured resonator filling factors are also in good agreement with those theoretically estimated. Both the theory and the experimental results suggest that the double-stacked DR structure with finite spacing between the ceramic cylinders is the most suitable for EPR measurements of long lossy samples. PMID:9169212

  13. Three diverse solid phenolics with similar hyperfine EPR spectra - why?

    International Nuclear Information System (INIS)

    Full text: Among the 50 or so solid phenolics we have studied by EPR, only three have given evidence of hyperfine structure, and the spectra are quite similar, with two lesser lines symmetrically placed about a higher central line. The specimens were: a phenolic extract of green tea (Indena, S.p.a.), mainly epigallocatechin gallate; an extract of shiraz grapeseeds, mainly (-) epicatechin - 3 - O - gallate and its dimers and polymers, and a sample of 95% pure hesperidin. The commercially available grapeseed extracts Pycnogenol(R) and 'OPC'S' showed no EPR hyperfine structure. At low modulation levels for hesperidin, the two outer lines each split into two, but this did not happen for the other samples. The mean spacing of the outer lines from the central one was different for each sample. At 77 K, a Cu(2+) signal was detected in the grapeseed extract, but had become motionally broadened before room temperature, so could not contribute to the free radical signal: Cu (2+) was not detected in the other samples at 77K. Preparational details were only available for the grapeseed extract, since the other samples were commercial products. For the hyperfine structure to be seen, there must be a distinct anisotropy in the materials, rather than a glass-like structure. Is it crystallisation, or strain? We would welcome suggestions for the cause of the hyperfine structure becoming visible, and the similarity of the spectra

  14. EPR design: A combined approach on safety and economic competitiveness

    International Nuclear Information System (INIS)

    Starting in 1991, the French and German cooperation led to common work based on the experience of the two designers FRAMATOME and SIEMENS KWU with all their know how, the most important utilities in France and Germany operating NPP and the technical supports of the Licensing Authorities GRS and IPSN. The conclusion of that work was the issue in November 1997 and February 1999 respectively of two Basic Design reports for a European Pressurized Reactor (EPR) with a power of 4250 MWth and 4900 MWth. The Basic Design approach was led under two key items: Enhancement of the overall safety level by implementation of design measures to: make the plant less dependant to common cause failures; practically eliminate all high pressure core melt sequences which could lead to important radioactive releases to the environment; implement specific systems to face severe accident situation with low-pressure core melt. Use of the many years of experiences in two different nuclear designs is to reach an overall availability figure over 91%, partly due to design improvements on the safety level. With such an objective, demonstrated by feedback of experience on already operating plants, the EPR project can be proposed as a competitive alternative to the most recent fossil plants. (author)

  15. EDF is going to build 2 EPR at Hinkley Point

    International Nuclear Information System (INIS)

    2 EPR are going to be built at the Hinkley Point site (South-west region of England). The 2 reactors of a power output of 1650 MW each will cover 7% of the electricity need of the UK. The first reactor will be operating in 2022. The investment reaches 18.9 million euros and is shared between 3 main investors: EDF (40%), Areva (10%), and Chinese companies: CGN and CNNC (between 30 and 40%). The agreement signed between the British authorities and EDF stipulates that the selling price of electricity will be guaranteed for 30 years and fix to 89.50 pounds if EDF builds 2 more EPR at the Sizewell site and to 92.5 pounds otherwise. It is the first time in UK that a nuclear power station is built with no money from the government. The present energy mix of UK for the production of electricity is Coal (45%), natural gas (24%) and nuclear energy (20%). (A.C.)

  16. Potential use of wallboard (drywall) for EPR retrospective dosimetry

    International Nuclear Information System (INIS)

    Concern regarding the possibility of criminal or terrorist use of nuclear materials has led to an interest in developing the capability to measure radiation dose in a variety of natural and manufactured materials. Electron paramagnetic resonance (EPR) measurements of radiation dose following a radiological incident may aid in screening affected populations (triage) and in reconstruction of doses following accidents. One such EPR dosimeter is wallboard (drywall), a common construction material composed largely of gypsum (calcium sulphate dihydrate). We have identified the CO3- and SO3- dose-sensitive lines in drywall and developed a measurement protocol using the intensity of CO3- line. Proper background subtraction is a major difficulty, and we demonstrate a procedure based on alignment of a contaminant Mn2+ line. As a proof-of-concept, a wallboard panel was irradiated with a 60Co source, and a two-dimensional map of the absorbed dose was measured. While most aliquots yielded reasonably accurate doses, a spatially contiguous region of apparent dose-insensitivity in one panel was identified.

  17. EPR dosimetry of glass substrate of mobile phone LCDs

    International Nuclear Information System (INIS)

    Previous studies have shown that mineral glass from watches, windows and displays of personal electronic devices could be a suitable restrospective dosimeter in case of radiation accident. In this paper glass substrates of the window display of 100 mobile phones of different trademarks were analized by X-band cw-EPR before and after irradiation at 100 Gy. The objective of this study was to highlight some issues of EPR measurements of glass related to inter-sample variability of: i) signal line shape in irradiated and unirradiated glass; ii) signal intensity loss and line shape change with post-irradiation time; iii) signal changes induced by sample preparation and iv) signal changes induced by thermal annealing. Scope of the paper is to provide a phenomenological picture of the observed effects in order to give a warning about possible problems and to provide suggestions for future work. Explanation of the mechanisms and the causes leading to the observed effects was beyond the scope of this work. These preliminary results confirm that glass substrate of mobile phone displays should be considered as a fortuitous dosimeter in radiation accidents. However, albeit very promising, mineral glass presents a number of issues that should be thoroughly investigated and addressed in future work.

  18. N-player quantum games in an EPR setting

    CERN Document Server

    Chappell, James M; Abbott, Derek

    2012-01-01

    The $N$-player quantum game is analyzed in the context of an Einstein-Podolsky-Rosen (EPR) experiment. In this setting, a player's strategies are not unitary transformations as in alternate quantum game-theoretic frameworks, but a classical choice between two directions along which spin or polarization measurements are made. The players' strategies thus remain identical to their strategies in the mixed-strategy version of the classical game. In the EPR setting the quantum game reduces itself to the corresponding classical game when the shared quantum state reaches zero entanglement. We find the relations for the probability distribution for $N$-qubit GHZ and W-type states, subject to general measurement directions, from which the expressions for the mixed Nash equilibrium and the payoffs are determined. Players' payoffs are then defined with linear functions so that common two-player games can be easily extended to the $N$-player case and permit analytic expressions for the Nash equilibrium. As a specific exa...

  19. Retrospective dosimetry by electronic paramagnetic resonance (EPR) in dental enamel

    International Nuclear Information System (INIS)

    Biophysical dosimetry based on EPR in biological solid samples (like bone and teeth) or in organic materials (like textile fibres, sugar, etc.) is a complementary technique that could contribute, along with the biological dosimetry, to the retrospective evaluation of the absorbed dose in accidental situations. Dental enamel could be considered as the only tissue with structure and composition essentially constant over time: this characteristic feature allows its use as an index of radiation exposure since tooth retains indefinitely its radiation history. Samples of human molars were exposed to gamma-Rays (Co 60) with doses between 0,5 Gy to 10 Gy. After a chemical treatment of samples, enamel was removed by grinding with a dental drill and reduced to a fine powder. A characteristic EPR signal was detected at g=2.002. The dose effect curves were done using 20 mw of microwave power. Measurements were done both, with flat cells and disposable Pasteur pipettes allowing the use of lower amounts of sample. The intensity of the signal was proportional to the dose and linearity was verified in both cases. We discuss the applicability of this technique in evaluating radiation dose in accidental overexposures. (author)

  20. EPR study of gamma-irradiated single crystal 4-phenylsemicarbazide

    International Nuclear Information System (INIS)

    Single crystals of 4-phenylsemicarbazide (4PSC) were investigated using an electron paramagnetic resonance (EPR) technique, with γ irradiation of the crystals at different orientations in the magnetic field between temperatures of 120 and 450 K, and the spectra were found to be temperature independent. Taking into consideration the chemical structure and the experimental spectra of the irradiated single crystal 4PSC, we assumed that one or more paramagnetic species were produced, each having an unpaired electron delocalized in the phenyl ring. Pursuant to this assumption, six possible radicals were modeled using the B3LYP/6-311+G(d) level of density-functional theory. EPR parameters were calculated for these modeled radicals using the B3LYP method and TZVP basis set. The calculated hyperfine coupling constants were used as starting points for simulations. The experimental and simulated spectra for each of the three crystallographic axes were well matched for the modeled radical R6. We thus identified the R6 (C6H5NH) radical as a paramagnetic species produced in 4PSC. The experimental g-factor and hyperfine coupling constants of the C6H5NH radical were found to be anisotropic, with the average values g=2.00431, aNHN(8)=8.85G, aNHH(9)=16.85G, ao,pH(14,16,20)=6.47G, and amH(18,19)=2.80G.

  1. Hydraulics in the RPV lower-plenum of EPR

    Energy Technology Data Exchange (ETDEWEB)

    Barois, G.; Goreaud, N.; Nicaise, N. [FRAMATOME, 92 - Paris-La-Defence (France)

    2001-07-01

    The in-core instrumentation penetrations of the European Pressurised water Reactor (EPR) have been removed from RPV-bottom to RPV-head, leaving empty the lower plenum of the RPV (Reactor Pressure Vessel). In a lower plenum with no internal structure, huge vortices may appear, with negative consequences, such as high disturbance of the core inlet flow distribution, and high increase of the RPV pressure loss. FRAMATOME ANP developed a specific Flow Distribution Device (FDD), annular shaped, located in the RPV lower plenum below the core support plate, which prevents huge vortices from appearing and guarantees a satisfying flow distribution at core inlet in normal operating conditions. The design of the FDD has been optimised with a numerical approach, using the 3-D CFD-code STAR-CD, previously qualified on scale mockup tests. The model developed represents the EPR RPV from the cold leg to core inlet. Thus, the flow distribution at core inlet, the mixing between loop-flows upstream core inlet and the pressure loss in the lower plenum can be evaluated. The optimised FDD provides satisfying performances for all these relevant functional items. (author)

  2. Antioxidant properties of tea investigated by EPR spectroscopy.

    Science.gov (United States)

    Polovka, Martin; Brezová, Vlasta; Stasko, Andrej

    2003-10-01

    The antioxidant properties of green, black and mixed (fruit) tea samples of different origin were investigated by means of EPR spectroscopy. A six line EPR spectrum of solid tea samples indicates the presence of Mn(II) ions and it is superimposed with a sharp singlet line attributed to semiquinone radical species (Delta H(pp)=1 mT; g=2.0022). Antioxidant properties of aqueous tea extracts in H(2)O(2)/NaOH/dimethylsulfoxide system generating reactive radicals (*OH, O(2)*-), *CH(3)) were followed by spin trapping technique. In addition, antioxidant capacity of these samples was assessed using stable radicals 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 4-hydroxy-2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPOL). Typically, the highest antioxidant potential to terminate superoxide radicals was found in green teas, followed by black and fruity teas. The pro-oxidant activity of green teas evidenced by spin traps was promoted in samples with higher Mn(II) and ascorbic acid concentrations. Various sources of free radicals used in the antioxidant tests due to their specific action show different termination rates in the presence of the individual tea samples. PMID:14516911

  3. Identification of irradiated food by EPR-spectroscopy and tomography

    Energy Technology Data Exchange (ETDEWEB)

    Groth, N. (KAI e.V., Tomographie-Labor, Berlin (Germany)); Anders, B. (Technische Fachhochschule Berlin (Germany). Fachbereich Mathematik/Physik); Maerzke, A. (Forschungsstelle fuer Ortsaufloesende Messtechnik e.V., Berlin (Germany)); Nitschke, S. (KAI e.V., Tomographie-Labor, Berlin (Germany)); Schlawe, R. (Forschungsstelle fuer Ortsaufloesende Messtechnik e.V., Berlin (Germany)); Herrling, T. (KAI e.V., Tomographie-Labor, Berlin (Germany))

    1993-01-01

    Food irradiation is used to kill harmful microorganisms (e.g. salmonella), this improving food safety and extending the shelf-life. The electron paramagnetic resonance (EPR) detection of stable, radiation-induced free radicals within the matrix of calcified tissue is well established. An extention of this technique to food provides in suitable cases one of the most promissing methods for detecting that irradiation has been performed. It provides an excellent method for the identification of irradiated foods containing bones or calcified cuticle even in the absence of unirradiated controls. Bones of chicken, pepper grains and lentils were also identified as irradiated some weeks after radiation treatment. The method is rapid and can detect very low doses. With EPR - Tomography the 2D spatial distribution of the irradiation induced stable radicals in the cross section of a chicken bone was measured. The use of ionising radiation to treat certain foodstuffs is increasingly of interest and there is a need to determine wether irradiation has occured, and to what extent. (orig.)

  4. Influencia de las mezclas de gases Ar-He y Ar-He-O2 en la soldabilidad de la aleación de aluminio AA5083-O usando Proceso GMAW-P automatizado

    Directory of Open Access Journals (Sweden)

    Enrique Esteban Niebles Nuñez

    2014-09-01

    Full Text Available La problemática en las empresas fabricantes de estructuras y construcciones soldadas en aluminio se centra en la disminución de las propiedades mecánicas de las uniones soldadas influenciada por el aporte térmico en las regiones de soldadura; así como, en los efectos de las discontinuidades y defectos, los altos costos de reparación de soldaduras y la baja productividad. El objetivo de este trabajo es evaluar la influencia de las mezclas de gases 80Ar20He (MG1, 60Ar40He (MG2, 80Ar19He1O2 (MG3, 60Ar39He1O2 (MG4, sobre la soldabilidad de la aleación de aluminio AA5083-O utilizando un material de aporte ER5183 y el proceso GMAW-P automatizado. La metodología incluyó una fase de parametrización de soldaduras, la caracterización del metal base y las regiones de soldadura. El análisis de resultados se llevó a cabo en términos de la evolución microestructural en las regiones de soldadura y evaluación de las propiedades como dureza, resistencia y elongación, así como la evaluación de discontinuidades y defectos de la unión, costos y velocidad de soldadura. Los resultados muestran que las mezclas de gas que contienen O2 favorecen significativamente la soldabilidad de la aleación en estudio.

  5. Erection progress of OL3 and other EPR projects

    International Nuclear Information System (INIS)

    The progress being made on the construction of the world's first EPR at Olkiluoto in Finland is clear to see: after work had started in October 2006 on the first civil structures for the reactor building, 2007 witnessed the other buildings also gradually taking shape. A key milestone was reached on June 7 when the first ring of the containment liner weighing no less than 218 tons was rigged into the reactor building. This had been preceded by completion of the turbine foundations inside the turbine building on April 28 following a concreting operation that had lasted 40 hours, allowing installation of the turbine condensers to then proceed. The very first component to be brought into the reactor building - a drain tank - was installed in mid-September. Fabrication of the major components is also well underway: the reactor pressure vessel at MHI in Japan, for example, will be completely finished as soon as it has passed its final pressure test in February 2008. And at AREVA's factory in Chalon, France, the first of the steam generators was recently fitted with all 6000 of its tubes having a total length of 140 km. Manufacturing of the other components is for the most part on schedule. Erection of the piping in the lower levels of the reactor building and the surrounding safeguard buildings should be starting in the spring of 2008. The number of employees on site will then rise to well over 2000. Handover of the 1st EPR will be from today's point of view mid 2011. Also in Flamanville in France where AREVA NP were charged by EOF with the turnkey delivery of the nuclear steam supply system the progress of preparation work is visible; in December 2007 there is the 1st concrete pouring, handover is planned for May 2012. In China AREVA NP will build 2 EPR Nl at the site of Taishan. Start of erection is scheduled September 2009 and the Chinese partners will be strongly involved in engineering, procurement and erection activities.

  6. Erection progress of OL3 and other EPR projects

    Energy Technology Data Exchange (ETDEWEB)

    Storr, Wolfgang [AREVA NP GmbH, Erlangen (Germany)

    2008-07-01

    The progress being made on the construction of the world's first EPR at Olkiluoto in Finland is clear to see: after work had started in October 2006 on the first civil structures for the reactor building, 2007 witnessed the other buildings also gradually taking shape. A key milestone was reached on June 7 when the first ring of the containment liner weighing no less than 218 tons was rigged into the reactor building. This had been preceded by completion of the turbine foundations inside the turbine building on April 28 following a concreting operation that had lasted 40 hours, allowing installation of the turbine condensers to then proceed. The very first component to be brought into the reactor building - a drain tank - was installed in mid-September. Fabrication of the major components is also well underway: the reactor pressure vessel at MHI in Japan, for example, will be completely finished as soon as it has passed its final pressure test in February 2008. And at AREVA's factory in Chalon, France, the first of the steam generators was recently fitted with all 6000 of its tubes having a total length of 140 km. Manufacturing of the other components is for the most part on schedule. Erection of the piping in the lower levels of the reactor building and the surrounding safeguard buildings should be starting in the spring of 2008. The number of employees on site will then rise to well over 2000. Handover of the 1st EPR will be from today's point of view mid 2011. Also in Flamanville in France where AREVA NP were charged by EOF with the turnkey delivery of the nuclear steam supply system the progress of preparation work is visible; in December 2007 there is the 1st concrete pouring, handover is planned for May 2012. In China AREVA NP will build 2 EPR Nl at the site of Taishan. Start of erection is scheduled September 2009 and the Chinese partners will be strongly involved in engineering, procurement and erection activities.

  7. The sensitivity analysis of tooth enamel to the absorbed dose for the application to EPR dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Dae Seok; Lee, Kun Jai [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of); Cho, Young Hwan [KAERI, Taejon (Korea, Republic of)

    2002-10-01

    Electron Paramagnetic Resonance (EPR) spectroscopy is one of the methods applicable to retrospective dosimetry. The retrospective dosimetry is a process that is a part of dose reconstruction for estimation of exposed dose occurred years before the estimation. Many techniques can be used to the retrospective dosimetry. As a physical method, EPR analysis of biological material measures the quantity of free radicals generated in the material from the interaction of radiation and material. Since the later 80s, in many countries, EPR dosimetry with tooth enamel has been studied and applied for the retrospective dosimetry. In the consideration of the biological materials for EPR dosimetry, human fingernail, hair, bone and tooth are generally considered. The tooth can be separated as enamel, dentine and cementum. Among the three parts, enamel shows the best sensitivity to the absorbed dose and is most widely used. In this study, the characteristics of tooth enamel for EPR dosimetry is examined and experimented. At the experiment, for easy separation, tooth was cut into 4 parts and then each part is treated by ultrasonic vibration in NaOH liquid to reduce mechanically induced noise in the corresponding signal. After the separation of the enamel from dentine, background EPR signal is measured and then radiation-induced EPR spectrum is estimated.

  8. An industrial strategy to master the construction of an EPR fleet from Flamanville 3

    International Nuclear Information System (INIS)

    Full text of publication follows. EDF's industrial strategy to master the construction of an EPR fleet from Flamanville 3 (FA3) rests on 3 base ideas. First, an organisation based on Architect engineer approach: As for the construction of the french NPP under operation, EDF approach for the construction of Flamanville 3 is to act as architect engineer that means EDF manages the project of construction in terms of quality, schedule and cost from the detailed design to manufacturing and site activities. EDF is also in interface with the french safety authority for the licensing and in charge to coordinate all the suppliers involved in the project. Secondly, a strong feed back organisation from FA3 experience: the construction of FA3 NPP is in line with the objective given by EDF for a connection to the grid in 2014: the civil phase is now in good progress and several buildings are already achieved. The electro-mechanical erected has started in all the buildings and the first commissioning tests occurred for the electrical distribution. From all these activities, EDF get the lessons learnt and has organised the feedback experience for the future EPR plants to be built. And thirdly, an EPR family organisation involving all EPR utilities partners of EDF: in order to share the experience gained on EPR under construction, EDF has created the EPR Family which gathers all the utilities involved in construction of EPR NPP in partnership with EDF. (author)

  9. EPR: steam generator tube rupture analysis in Finland and in France

    International Nuclear Information System (INIS)

    Different requirements between Finland and France lead EPR designer to define different features (system or action) for management of accidents on Olkiluoto 3 EPR that is under-construction in Finland compared to Flamanville 3 EPR that is foreseen in France. One of these differences concerns the management of Steam Generator Tube Rupture since no primary coolant (liquid and steam) release to the environment is allowed in Finland dislike in France where primary steam releases are not forbidden. This leads to define on Finnish EPR a strategy that anticipates mitigation action compared to French EPR and that only uses the unaffected steam generators. This strategy is intended to reduce the release to the environment. IRSN has analysed an other aspect of the Steam Generator Tube Rupture: the back-flow (flow of un-borated water from steam generator to the primary circuit). Indeed, if the Reactor Coolant Pumps have been shut down, the creation an un-borated water plug because of the back-flow could lead to reactivity accident in case of Reactor Coolant Pump restart. IRSN analysis shows that, using the current Olkiluoto 3 SGTR mitigation strategy and very penalizing assumptions, the amount of un-borated water transferred to the primary circuit on the Finnish EPR could be higher than on the French EPR in the long term. Discussions are going on between STUK and TVO to finalize the SGTR strategy so that both releases into the environment and risk of back-flow can be minimized. (author)

  10. Effect of microwave power on EPR spectra of natural and synthetic dental biocompatible materials

    Directory of Open Access Journals (Sweden)

    Adamczyk Jakub

    2015-07-01

    Full Text Available Paramagnetic centers in the two exemplary synthetic and natural dental biocompatible materials applied in implantology were examined by the use of an X-band (9.3 GHz electron paramagnetic resonance (EPR spectroscopy. The EPR spectra were measured in the range of microwave power 2.2–70 mW. The aims of this work were to compare paramagnetic centers concentrations in different dental biocompatible materials and to determine the effect of microwave power on parameters of their EPR spectra. It is the very first and innovatory examination of paramagnetic centers in these materials. It was pointed out that paramagnetic centers existed in both natural (~1018 spin/g and synthetic (~1019 spin/g dental biocompatible materials, but the lower free radical concentration characterized the natural sample. Continuous microwave saturation of EPR spectra indicated that faster spin-lattice relaxation processes existed in synthetic dental biocompatible materials than in natural material. Linewidths (ΔBpp of the EPR spectra of the natural dental material slightly increased for the higher microwave powers. Such effect was not observed for the synthetic material. The broad EPR lines (ΔBpp: 2.4 mT, 3.9 mT, were measured for the natural and synthetic dental materials, respectively. Probably strong dipolar interactions between paramagnetic centers in the studied samples may be responsible for their line broadening. EPR spectroscopy is the useful experimental method in the examination of paramagnetic centers in dental biocompatible materials.

  11. Medical reference dosimetry using EPR measurements of alanine

    DEFF Research Database (Denmark)

    Helt-Hansen, Jakob; Rosendal, F.; Kofoed, I.M.;

    2009-01-01

    beams. The typical difference between the dose measured with alanine in solid water and the dose measured with an ion chamber in a water tank was about 1%. A difference of 2% between 6 and 18 MV was found, possibly due to non-water equivalence of the applied phantom. Discussion. Compared to previously......Background. Electron spin resonance (EPR) is used to determine the absorbed dose of alanine dosimeters exposed to clinical photon beams in a solid-water phantom. Alanine is potentially suitable for medical reference dosimetry, because of its near water equivalence over a wide energy spectrum, low...... on scaling of known spectra was developed to extract the alanine signal. Results. The dose accuracy, including calibration uncertainty, is less than 2% (k=1) above 4 Gy (n=4). The measurement uncertainty is fairly constant in absolute terms (30 mGy) and the relative uncertainty therefore rises for...

  12. EPR Dosimetry of Pacific Walrus (Odobenus Rosmarus Divergens) Teeth

    Energy Technology Data Exchange (ETDEWEB)

    Hayes, R.B.; Kenner, G.H.; Haskell, E.H

    1998-07-01

    The potential for EPR dosimetry using walrus tooth cementum was examined. Using standard peak to peak methods, individual measurement errors of the dosimetric signal (g = 2.0018) were approximately 350 mGy (1 SD). Linearity of the dose response extended up to 6 kGy for large intact specimens. The dentin was found to have a larger g = 2.005 signal than the cementum and so was not investigated for linearity or sensitivity due to its expected higher organic content. A complex native signal was seen in all samples. A heat induced signal similar to that occurring in human tooth enamel was also observed. The signal was detectable at temperatures as low as 70 deg. C. Deorganification with diethylenetriamine using the Soxhlet extraction procedure decreased the initial dosimetric signal by a factor of 10. (author)

  13. Penetration stress analysis for high energy pipes in EPR units

    International Nuclear Information System (INIS)

    This paper introduced the characteristics of penetrations for high energy pipes in EPR units, and mainly presented the steps to do stress analysis. The analysis is divided into two steps: firstly, a thermal analysis, and secondly, a thermal-mechanical coupled analysis. The purpose of the thermal analysis is to demonstrate that temperature in the containment concrete is not too high. The purpose of the thermal-mechanical coupled analysis is to demonstrate the penetration stress criteria under each loading condition categories. According to the axisymmetric characteristics of penetration, a simplified plane model can be built. As a typical example, a stress calculation of penetration RIS DN200 was performed by using ANSYS procedure, and stress evaluation was done according to RCC-M. (authors)

  14. Hydrogen defect dynamics studied by EPR. Isotope and quantum effects

    International Nuclear Information System (INIS)

    We consider the case of the localized diffusion of several hydrogen related defects in MgO and CaO. Using the EPR technique we obtain information about the hopping processes, jumping rates and activation energies. Usually the energy level of the first excited vibrational state is such that the motion takes place by thermally activated jumps between the ground states. This is the case for [OH2-]0 and [H-Ca+]0 in CaO and Hi0(Li) in MgO. By contrast, for Hi0(Li) in CaO the first vibrational state is close enough to be partially populated at the temperature of measurement. To explain its dynamic behavior, we propose a model in which the reorientation takes place by a tunneling through the first excited vibrational state. (author)

  15. EPR = ER and Scattering Amplitude as Entanglement Entropy Change

    CERN Document Server

    Seki, Shigenori

    2014-01-01

    Alday and Maldacena have found an exact minimal surface of open string world-sheet describing a gluon scattering. We study the causal structure of that minimal surface in AdS of position space, and find a world-sheet wormhole parametrized by Mandelstam variables. If we figure a gluon as an open string in AdS, the ribbon connecting the two strings always pass the world-sheet wormhole, demonstrating the EPR = ER for gluon scattering. Since entanglement is caused by an interaction, one can ask what is the relation between entanglement entropy and the scattering amplitude. We propose an answer by generalizing the holographic entanglement entropy (EE) of Ryu-Takayanagi to the case where two regions are divided in space-time and interpret the result as the change of EE.

  16. Ensemble interpretation of the EPR-Bell correlations

    International Nuclear Information System (INIS)

    The EPR-Bell correlations between the spins of a pair of particles originally in a singlet state are discussed both on the basis of the mathematical formalism of quantum mechanics and the ensemble interpretation. It is shown that the correlations predicted by the mathematical formalism are in agreement with those expected on the basis of the ensemble interpretation, if the electrons are treated as distinguishable particles after they separate and undergo observation. In this case, the correlations are only in partial agreement with a gedanken experiment of Mermin on the subject. It is pointed out, however, that agreement with Mermin's conclusions is possible if one treats the electrons as indistinguishable even when they are subjected to observation, though there is no obvious theoretical justification for doing so. (author). 8 refs

  17. EPR dosimetry with synthetic A-type carbonated apatite

    International Nuclear Information System (INIS)

    Synthetic A-type carbonated apatite prepared in reproducible conditions were irradiated at room temperature with 60 Co γ rays. The EPR spectrum is associated to axial CO2- and orthorhombic CO3- species. Radicals used as dose marker in biological apatite are long live paramagnetic species. The stability of the post-irradiation signal of A-type apatite was investigated for more than one year. Measurements showed variations in the spectra attributed to unstable CO3- species, which can be eliminated by thermal treatments at 100 deg C for 24 hours. The CO2- spectrum can be identified in samples irradiated up to 0.2 Gy. All results indicate the A-type apatite as an appropriate material for radiotherapy dosimetry. (author)

  18. EPR: high load variation performances with the 'TMODE' core control

    International Nuclear Information System (INIS)

    The load variation performances on a PWR are directly linked to the core control design. This design is mainly characterized by the definition of the control rod banks and the way to both perform the banks movements and to modify the core boron concentration by injection of boric acid or water. The following paper presents the principles of the T mode, the new fully automatic core control mode for the EPR which provides high performance in terms of maneuverability and optimizes the effluents. First, the paper describes the division of the control rods into two control banks (Pbank for temperature and Hbank for power distribution). Then typical movements of these banks during power changes are shown. Then, the principle of the 3 control loops (Tave, AO, Pmax), used to obtain these desired control rod movements, is given. Finally, a load following transient simulation is presented. (author)

  19. Alanine-EPR dosimetry system. Why we like it?

    International Nuclear Information System (INIS)

    To develop a new high-dose dosimeter we should: (1) to find material with radiation effect monotonically (if possible linearly) dependent on an absorbed dose; (2) to investigate its dosimetric characteristics (sensitivity, dose range, repeatability, accuracy, post-effects); (3) to evaluate economical parameters of new method (cost and availability of dosimetric material, cost of analytical instrument and its services); (4) to evaluate operational features of new dosimeter (sensitivity for environmental conditions, time from irradiation to the read-out); (5) to perform a calibration curve, i.e. functional dependence between radiation effect (dosimetric signal) and absorbed dose. On the base of this very stable stable ammonium radical (SAR) generated in crystalline α-alanine was established in the INCT as an alanine-EPR dosimetry system. Presented lecture describes the main features of this dosimeter

  20. Alanine/EPR dosimetry as a reference system in radiotherapy

    International Nuclear Information System (INIS)

    Full text: It is widely accepted that dosimetry intercomparisons are a key step in the continuous quality improvement programmes in radiotherapy (CQIR). Indeed, they offer the possibility to detect and evaluate errors in dose delivery. Similarly to other European and international actions, the ISS is promoting a network of dosimetry intercomparisons among radiotherapy centres. The alanine/EPR system is used as reference dosimetry for the ISS dosimetry intercomparisons. The reduced energy dependence, absence of fading, 1% (1σ) accuracy, robustness for mail delivery and non-destructive read-out procedure are the main characteristics that substantiate the choice of alanine. TLD-100 are also being used, but only for relative measurements. Alanine dosimetry has been developed at ISS and has been calibrated by the Primary Dosimetry Laboratory in Italy (INMRI- ENEA). In the framework of CQIR programmes, the ISS launched two different postal dosimetry intercomparisons: (a) for conventional treatments using external high-energy photon beams, and (b) for protontherapy centres which treat ocular melanomas. High energy photon beams: The purpose is to check the accuracy in the doses delivered under reference conditions and for a simulated treatment, through the analysis of the differences between measured and stated doses. The accuracy will depend on the procedures adopted in the radiation therapy centres, including the dosimetric protocol, the CT imaging and the treatment plan system used for the dose calculation. Two irradiation conditions have been chosen. In the first, a water phantom will be irradiated where the dose will be measured at a reference point. In the second, a rectum cancer treatment will be simulated, delivering the dose to an anthropomorphic phantom which will be measured at the isocentre and at 5 other previously defined points. In the first phase, the intercomparison will include only 16 centres and will be considered as a pilot project. The

  1. Effect of irradiation on chemiluminescence of EPR pure valcanisate

    International Nuclear Information System (INIS)

    Chemiluminescence of ethylene-propylene pure rubber which is irradiated at various doses was measured. Three methods were attempted to obtain the temperature dependence of the counts of luminescence. In the first method, the relationship between counts of luminescence and time at constant temperature was measured, and the maximum value of counts per unit time is defined as the counts at the temperature (maximum counts method). The relationship between the counts and the passage time was found to be maxwellian after a certain period of time. The extrapolated value to time 0 was defined as the initial count of luminescence in the second method (extrapolate method). In the third method, temperature of the samples was raised stepwise and the counts of each temperature was measured (temperature rising method). Irradiation of 2.7 kGy increases the amount of luminescence remarkably, although the mechanical properties are not affected significantly at the dose. The counts of luminescence does not increase linearly with increasing dose. The counts were found to level off at about 50 kGy. This is because the antioxidant agent which is added during production process of EPR is consumed by irradiation. The results suggests that the rate of autoxidation of the constant temperature depends on whether an antioxidant agent exists or not. The activation energy of the count of CL did not change irrespective of irradiation, and was 82.7 kJ/mol in the extrapolate method. On the other hand, the activation energy for non-irradiated EPR was lower than that of irradiated samples in the maximum counts method, but higher than the values of irradiated samples in the temperature rising method. (author)

  2. N-Player Quantum Games in an EPR Setting

    Science.gov (United States)

    Chappell, James M.; Iqbal, Azhar; Abbott, Derek

    2012-01-01

    The -player quantum games are analyzed that use an Einstein-Podolsky-Rosen (EPR) experiment, as the underlying physical setup. In this setup, a player’s strategies are not unitary transformations as in alternate quantum game-theoretic frameworks, but a classical choice between two directions along which spin or polarization measurements are made. The players’ strategies thus remain identical to their strategies in the mixed-strategy version of the classical game. In the EPR setting the quantum game reduces itself to the corresponding classical game when the shared quantum state reaches zero entanglement. We find the relations for the probability distribution for -qubit GHZ and W-type states, subject to general measurement directions, from which the expressions for the players’ payoffs and mixed Nash equilibrium are determined. Players’ payoff matrices are then defined using linear functions so that common two-player games can be easily extended to the -player case and permit analytic expressions for the Nash equilibrium. As a specific example, we solve the Prisoners’ Dilemma game for general . We find a new property for the game that for an even number of players the payoffs at the Nash equilibrium are equal, whereas for an odd number of players the cooperating players receive higher payoffs. By dispensing with the standard unitary transformations on state vectors in Hilbert space and using instead rotors and multivectors, based on Clifford’s geometric algebra (GA), it is shown how the N-player case becomes tractable. The new mathematical approach presented here has wide implications in the areas of quantum information and quantum complexity, as it opens up a powerful way to tractably analyze N-partite qubit interactions. PMID:22606258

  3. N-player quantum games in an EPR setting.

    Directory of Open Access Journals (Sweden)

    James M Chappell

    Full Text Available The N-player quantum games are analyzed that use an Einstein-Podolsky-Rosen (EPR experiment, as the underlying physical setup. In this setup, a player's strategies are not unitary transformations as in alternate quantum game-theoretic frameworks, but a classical choice between two directions along which spin or polarization measurements are made. The players' strategies thus remain identical to their strategies in the mixed-strategy version of the classical game. In the EPR setting the quantum game reduces itself to the corresponding classical game when the shared quantum state reaches zero entanglement. We find the relations for the probability distribution for N-qubit GHZ and W-type states, subject to general measurement directions, from which the expressions for the players' payoffs and mixed Nash equilibrium are determined. Players' N x N payoff matrices are then defined using linear functions so that common two-player games can be easily extended to the N-player case and permit analytic expressions for the Nash equilibrium. As a specific example, we solve the Prisoners' Dilemma game for general N ≥ 2. We find a new property for the game that for an even number of players the payoffs at the Nash equilibrium are equal, whereas for an odd number of players the cooperating players receive higher payoffs. By dispensing with the standard unitary transformations on state vectors in Hilbert space and using instead rotors and multivectors, based on Clifford's geometric algebra (GA, it is shown how the N-player case becomes tractable. The new mathematical approach presented here has wide implications in the areas of quantum information and quantum complexity, as it opens up a powerful way to tractably analyze N-partite qubit interactions.

  4. EPR investigation of some desiccated Ascomycota and Basidiomycota gamma-irradiated mushrooms

    International Nuclear Information System (INIS)

    The suitability of the EPR spectroscopy for detection of γ-irradiation in five species of dried mushroom, currently used in gastronomy: yellow morel-Morchella esculenta, (L.) Pers. (Phylum Ascomycota), button mushroom-Agaricus bisporus (J.E.Lange), Agaricus haemorrhoidarius Fr., golden chantarelle-Cantharellus cibarius Fr., as well as oyster mushroom-Pleurotus ostreatus (Jacq. ex Fr.) (Phylum Basidiomycota) is presented and discussed. Although after irradiation at doses up to 11 kGy, all specimens presented well defined EPR spectra, only A. bisporus EPR signal was enough stable to make detection possible after 18 months.

  5. Electronic Paramagnetic Resonance (EPR) of free radicals induced by X-rays in pyrene

    International Nuclear Information System (INIS)

    Pyrene single crystals C16H10, irradiated by X-rays, at room temperature, were studied by EPR technique, to determine free radicals formed by radiation. The angular dependence of EPR spectra was explained by the presence of two kinds of radicals with an aditional hydrogen: 2-H2 pyrene and 3-H2 pyrene. It was studied the isothermic decay of the EPR signal and two typical values for the activation energy were found = (1,9+-0,1) eV and (1,93+-0,03) eV. (author)

  6. EPR as an analytical tool in assessing the mineral nutrients and irradiated food products-vegetables

    Science.gov (United States)

    Prasuna, C. P. Lakshmi; Chakradhar, R. P. S.; Rao, J. L.; Gopal, N. O.

    2008-12-01

    EPR spectral investigations of some commonly available vegetables in south India, which are of global importance like Daucus carota (carrot), Cyamopsis tetragonoloba (cluster beans), Coccinia indica (little gourd) and Beta vulgaris (beet root) have been carried out. In all the vegetable samples a free radical corresponding to cellulose radical is observed. Almost all the samples under investigation exhibit Mn ions in different oxidation states. The temperature variation EPR studies are done and are discussed in view of the paramagnetic oxidation states. The radiation-induced defects have also been assessed by using the EPR spectra of such irradiated food products.

  7. Identification of irradiated fruit from the pectin-derived EPR signal

    International Nuclear Information System (INIS)

    An EPR method based upon the observation of an unidentified multiline spectrum has been reported for the detection of irradiated fruit (dried papaya, banana, dates). A similar long-lived EPR spectrum after irradiation of dried amorphous apple pectin (BDH, 6% methyl ester) suggesting that pectin might be the origin of the signal in the dried fruit. Compositions of pectins vary greatly according to source and also with the age of the fruit itself. Therefore, a series of pectins of citrus fruit and potato tuber origin have been investigated to examine the effects of different levels of esterification on the irradiation-induced EPR signal. (author)

  8. EPR dosimetric properties of 2-methylalanine pellet for radiation processing application

    Science.gov (United States)

    Soliman, Y. S.; Ali, Laila I.; Moustafa, H.; Tadros, Soad M.

    2014-09-01

    The dosimetric characteristics of γ-radiation induced free radicals in 2-methylalanine (2MA) pellet dosimeter are investigated using electron paramagnetic resonance (EPR) in the high-dose range of 1-100 kGy. The EPR spectrum of γ-irradiated 2MA exhibits an isotropic EPR signal with seven lines. The dosimeter response is humidity independent in the range of 33-76% relative humidity. The manufactured dosimeter is typically adipose tissue equivalent in the energy level of 0.1-15 MeV. The overall uncertainty (2σ) of the dosimeter is less than 6.9%.

  9. EPR investigation of some desiccated Ascomycota and Basidiomycota gamma-irradiated mushrooms

    Energy Technology Data Exchange (ETDEWEB)

    Bercu, V., E-mail: vbercu@gmail.co [University of Bucharest, Department of Atomic and Nuclear Physics, P.O. Box MG-11, 077125 Magurele (Ilfov) (Romania); Negut, C.D., E-mail: dnegut@nipne.r [University of Bucharest, Department of Atomic and Nuclear Physics, P.O. Box MG-11, 077125 Magurele (Ilfov) (Romania); Horia Hulubei National Institute for Physics and Nuclear Engineering, P.O. Box MG-6, 077125 Magurele (Ilfov) (Romania); Duliu, O.G., E-mail: duliu@b.astral.r [University of Bucharest, Department of Atomic and Nuclear Physics, P.O. Box MG-11, 077125 Magurele (Ilfov) (Romania)

    2010-12-15

    The suitability of the EPR spectroscopy for detection of {gamma}-irradiation in five species of dried mushroom, currently used in gastronomy: yellow morel-Morchella esculenta, (L.) Pers. (Phylum Ascomycota), button mushroom-Agaricus bisporus (J.E.Lange), Agaricus haemorrhoidarius Fr., golden chantarelle-Cantharellus cibarius Fr., as well as oyster mushroom-Pleurotus ostreatus (Jacq. ex Fr.) (Phylum Basidiomycota) is presented and discussed. Although after irradiation at doses up to 11 kGy, all specimens presented well defined EPR spectra, only A. bisporus EPR signal was enough stable to make detection possible after 18 months.

  10. EPR investigation of some desiccated Ascomycota and Basidiomycota gamma-irradiated mushrooms

    Science.gov (United States)

    Bercu, V.; Negut, C. D.; Duliu, O. G.

    2010-12-01

    The suitability of the EPR spectroscopy for detection of γ-irradiation in five species of dried mushroom, currently used in gastronomy: yellow morel— Morchella esculenta, (L.) Pers. (Phylum Ascomycota), button mushroom— Agaricus bisporus (J.E.Lange), Agaricus haemorrhoidarius Fr., golden chantarelle— Cantharellus cibarius Fr., as well as oyster mushroom— Pleurotus ostreatus (Jacq. ex Fr.) (Phylum Basidiomycota) is presented and discussed. Although after irradiation at doses up to 11 kGy, all specimens presented well defined EPR spectra, only A. bisporus EPR signal was enough stable to make detection possible after 18 months.

  11. Time dependence of the radiation-induced EPR signal in sucrose

    International Nuclear Information System (INIS)

    Sucrose and common household sugars (e.g. cane) have been studied as dosemeters for a wide variety of applications. However, previous studies of the post-irradiation time dependence of irradiated sugar did not include an electron paramagnetic resonance (EPR) reference material. This work employs synthetic ruby as an EPR reference material to remove significant spectrometer/environmental influences on the measured time-dependent changes in the EPR spectral amplitude of irradiated sucrose. As such, these more accurate measurements should replace the previously published data. (authors)

  12. Identification of irradiated fruit from the pectin-derived EPR signal

    Energy Technology Data Exchange (ETDEWEB)

    Deighton, N.; Glidewell, S.M.; Goodman, B.A.; McMillan, G.P.; Perombelon, M.C.M. [Scottish Crop Research Inst., Dundee (United Kingdom)

    1996-12-31

    An EPR method based upon the observation of an unidentified multiline spectrum has been reported for the detection of irradiated fruit (dried papaya, banana, dates). A similar long-lived EPR spectrum after irradiation of dried amorphous apple pectin (BDH, 6% methyl ester) suggesting that pectin might be the origin of the signal in the dried fruit. Compositions of pectins vary greatly according to source and also with the age of the fruit itself. Therefore, a series of pectins of citrus fruit and potato tuber origin have been investigated to examine the effects of different levels of esterification on the irradiation-induced EPR signal. (author).

  13. Radicals as EPR probes of magnetization of gadolinium stearate Langmuir-Blodgett film

    DEFF Research Database (Denmark)

    Koksharov, Y.A.; Bykov, I.V.; Malakho, A.P.; Polyakov, S.N.; Khomutov, G.B.; Bohr, Jakob

    2002-01-01

    In the present work we have applied the method of the EPR spin probes which allows performing simultaneously EPR and magnetization measurements to the investigation of magnetism of the Cid stearate Langmuir-Blodgett (LB) films. For this purpose we have prepared and studied by the EPR technique th...... corresponded to the magnetization of the film along the field direction. Such effect has not been observed for the Y stearate LB film. The data obtained give an experimental proof for the room temperature. magnetic ordering in the! gadolinium stearate LB film....

  14. UV EFFECTS IN TOOTH ENAMEL AND THEIR POSSIBLE APPLICATION IN EPR DOSIMETRY WITH FRONT TEETH

    OpenAIRE

    Sholom, S.; Desrosiers, M; Chumak, V; Luckyanov, N; Simon, S. L.; Bouville, A.

    2010-01-01

    The effects of ultraviolet (UV) radiation on ionizing radiation biodosimetry were studied in human tooth enamel samples using the technique of electron paramagnetic resonance (EPR) in X-band. For samples in the form of grains, UV-specific EPR spectra were spectrally distinct from that produced by exposure to gamma radiation. From larger enamel samples, the UV penetration depth was determined to be in the 60–120 μm range. The difference in EPR spectra from UV exposure and from exposure to gamm...

  15. Effect of microwave power on EPR spectra of natural and synthetic dental biocompatible materials

    OpenAIRE

    Adamczyk Jakub; Ramos Paweł; Pilawa Barbara

    2015-01-01

    Paramagnetic centers in the two exemplary synthetic and natural dental biocompatible materials applied in implantology were examined by the use of an X-band (9.3 GHz) electron paramagnetic resonance (EPR) spectroscopy. The EPR spectra were measured in the range of microwave power 2.2–70 mW. The aims of this work were to compare paramagnetic centers concentrations in different dental biocompatible materials and to determine the effect of microwave power on parameters of their EPR spectra. It i...

  16. Taurine-EVA copolymer-paraffin rods dosimeters for EPR high-dose radiation dosimetry

    OpenAIRE

    Maghraby Ahmed M.; Mansour A; Abdel-Fattah A. A.

    2014-01-01

    Taurine/EPR rods (3 × 10 mm) have been prepared by a simple technique in the laboratory where taurine powder was mixed with a molten mixture of paraffin wax and an ethylene vinyl acetate (EVA) copolymer. The binding mixture EVA/Paraffin does not present interference or noise in the EPR signal before or after irradiation. The rods show good mechanical properties for safe and multi-use handling. An EPR investigation of radiation induced radicals in taurine rods revealed that there are two types...

  17. EPR study of the annealing effects on the x-ray-irradiated l-alanine

    International Nuclear Information System (INIS)

    L-alanine has been discovered to be one of the best emergency dosimetric materials. In this research, the dosimetric properties of L-alanine were re-examined using an electron paramagnetic resonance (EPR) spectrometer. The intensities of the EPR signal were measured at room temperature after a 30-minute annealing at various temperatures. We investigated the annealing effect on the samples for various temperatures in the range from -10 .deg. C to 50 .deg. C by using EPR. These intensities depend on the areal, daily,and seasonal temperatures

  18. Growth and EPR properties of ErVO4 single crystals

    Directory of Open Access Journals (Sweden)

    Leniec Grzegorz

    2015-07-01

    Full Text Available Single crystals of ErVO4 were grown by the Czochralski method under ambient pressure in a nitrogen atmosphere. Obtained crystals were transparent with strong pink coloring. Electron paramagnetic resonance (EPR spectra were recorded as a function of the applied magnetic field. Temperature and angular dependences of the EPR spectra of the samples in the 3–300 K temperature range were analyzed applying both Lorentzian––Gauss approximation for diluted medium and Dyson for dense magnetic medium. EPR-NMR program was done to find local symmetry and spin Hamiltonian parameters of erbium ions.

  19. Photochemical reduction of water-soluble C60 derivatives (EPR study)

    International Nuclear Information System (INIS)

    The photochemical reduction of three bis-functionalized C60 derivatives resulted in the formation of a single radical product, characterized by relatively narrow EPR line (gM = 2.0007, pp < 0.02 mT). In the irradiated aqueous solutions containing L-ascorbic acid, in the addition to the EPR line related to bis-adduct mono-anion, also 6-line EPR spectrum of ascorbyl radical was observed. Consequently, the photoinduced formation of ascorbyl radical was attributed to the intermolecular quenching of fullerenes excited states. (authors)

  20. Bell Correlated and EPR States in the Framework of Jordan Algebras

    Science.gov (United States)

    Hamhalter, Jan; Sobotíková, Veronika

    2016-03-01

    We study Bell inequalities and EPR states in the context of Jordan algebras. We show that the set of states violating Bell inequalities across two operator commuting nonmodular Jordan Banach algebras is norm dense in the global state space. It generalizes hitherto known results in quantum field theory in several directions. We propose new Jordan quantity for incommensurable observables in a given state, introduce the concept of EPR state for Jordan structures, and study relationship between EPR states and Bell correlated states. Our analysis shows crucial role of spin factors and Pauli spin matrices for studying noncommutative properties of states and observables.

  1. Characterizing Active Pharmaceutical Ingredient Binding to Human Serum Albumin by Spin-Labeling and EPR Spectroscopy.

    Science.gov (United States)

    Hauenschild, Till; Reichenwallner, Jörg; Enkelmann, Volker; Hinderberger, Dariush

    2016-08-26

    Drug binding to human serum albumin (HSA) has been characterized by a spin-labeling and continuous-wave (CW) EPR spectroscopic approach. Specifically, the contribution of functional groups (FGs) in a compound on its albumin-binding capabilities is quantitatively described. Molecules from different drug classes are labeled with EPR-active nitroxide radicals (spin-labeled pharmaceuticals (SLPs)) and in a screening approach CW-EPR spectroscopy is used to investigate HSA binding under physiological conditions and at varying ratios of SLP to protein. Spectral simulations of the CW-EPR spectra allow extraction of association constants (KA ) and the maximum number (n) of binding sites per protein. By comparison of data from 23 SLPs, the mechanisms of drug-protein association and the impact of chemical modifications at individual positions on drug uptake can be rationalized. Furthermore, new drug modifications with predictable protein binding tendency may be envisaged. PMID:27460503

  2. Preparation and EPR characterization of N@C60 and N@C70 based peapods

    Science.gov (United States)

    Corzilius, B.; Gembus, A.; Weiden, N.; Dinse, K.-P.

    2005-09-01

    Using the quartet spin of encased nitrogen atoms as an electron paramagnetic resonance (EPR) probe, it is possible to examine the fullerene/nanotube interactions in a peapod. A purification method is developed which allows low temperature filling of nanotubes with endohedral fullerenes. The paramagnetic impurities of undoped single wall carbon nanotubes (SWNT) are characterized via EPR resulting in a broad superparamagnetic signal of the remaining catalyst particles and a rather narrow signal of carbonaceous material. Comparison of EPR spectra of several nitrogen endohedral doped peapods with their analogues obtained in a solid fullerene matrix shows a significant broadening of N@C60 and N@C70 EPR signals. This broadening is related to a non-vanishing zero-field splitting caused by deformation of the fullerene cage upon encapsulation.

  3. Wormhole and Entanglement (Non-)Detection in the ER=EPR Correspondence

    CERN Document Server

    Bao, Ning; Remmen, Grant N

    2015-01-01

    The recently proposed ER=EPR correspondence postulates the existence of wormholes (Einstein-Rosen bridges) between entangled states (such as EPR pairs). Entanglement is famously known to be unobservable in quantum mechanics, in that there exists no observable (or, equivalently, projector) that can accurately pick out whether a generic state is entangled. Many features of the geometry of spacetime, however, are observables, so one might worry that the presence or absence of a wormhole could identify an entangled state in ER=EPR, violating quantum mechanics, specifically, the property of state-independence of observables. In this note, we establish that this cannot occur: there is no measurement in general relativity that unambiguously detects the presence of a generic wormhole geometry. This statement is the ER=EPR dual of the undetectability of entanglement.

  4. Wormhole and entanglement (non-)detection in the ER=EPR correspondence

    Science.gov (United States)

    Bao, Ning; Pollack, Jason; Remmen, Grant N.

    2015-11-01

    The recently proposed ER=EPR correspondence postulates the existence of wormholes (Einstein-Rosen bridges) between entangled states (such as EPR pairs). Entanglement is famously known to be unobservable in quantum mechanics, in that there exists no observable (or, equivalently, projector) that can accurately pick out whether a generic state is entangled. Many features of the geometry of spacetime, however, are observables, so one might worry that the presence or absence of a wormhole could identify an entangled state in ER=EPR, violating quantum mechanics, specifically, the property of state-independence of observables. In this note, we establish that this cannot occur: there is no measurement in general relativity that unambiguously detects the presence of a generic wormhole geometry. This statement is the ER=EPR dual of the undetectability of entanglement.

  5. Experience feed back of nuclear island design schedule construction and management in EPR project

    International Nuclear Information System (INIS)

    In the EPR project construction progress, with method of observing schedule system part by part, then as a whole, compare the EPR schedule management methods with CPR1000. Especially focus on EPR nuclear island design schedule construction method-First construction schedules divided, then establish links with different project schedule as a whole. And compare EPR NI design schedule with CPR1000 in EPS, WBS and so on, at the same time also explaining the important function of interface project which between upstream schedule and downstream schedule. Present civil work, system and layout design schedule construction ways of nuclear island, and discuss about the time arrangement of these milestones, to achieve the target of experience feed back. (authors)

  6. EPR investigations of silicon carbide nanoparticles functionalized by acid doped polyaniline

    Energy Technology Data Exchange (ETDEWEB)

    Karray, Fekri [Laboratoire des materiaux Ceramiques Composites et Polymeres, Faculte des Sciences de Sfax, BP 802, 3018 Sfax (Tunisia); Kassiba, Abdelhadi, E-mail: kassiba@univ-lemans.fr [Institute of Molecules and Materials of Le Mans (I3M), UMR-CNRS 6283, Universite du Maine, 72085 Le Mans (France)

    2012-06-15

    Nanocomposites (SiC-PANI) based on silicon carbide nanoparticles (SiC) encapsulated in conducting polyaniline (PANI) are synthesized by direct polymerization of PANI on the nanoparticle surfaces. The conductivity of PANI and the nanocomposites was modulated by several doping levels of camphor sulfonic acid (CSA). Electron paramagnetic resonance (EPR) investigations were carried out on representative SiC-PANI samples over the temperature range [100-300 K]. The features of the EPR spectra were analyzed taking into account the paramagnetic species such as polarons with spin S=1/2 involved in two main environments realized in the composites as well as their thermal activation. A critical temperature range 200-225 K was revealed through crossover changes in the thermal behavior of the EPR spectral parameters. Insights on the electronic transport properties and their thermal evolutions were inferred from polarons species probed by EPR and the electrical conductivity in doped nanocomposites.

  7. USE OF-EPR-DL FIELD TEST EQUIPMENT FOR DETECTION OF SIGMA PHASE

    Directory of Open Access Journals (Sweden)

    Abraão Danilo Gomes Barreto

    2014-06-01

    Full Text Available This work has objective to correlate the intergranular corrosion susceptibility test named EPR-DL (Electrochemical Potentiokinetic Reactivation of Double Loop with the sigma phase formation and other phases. It has been used samples from a UNS S32760 steel pipe for conducting various aging heat treatments. Held isothermal heat treatment at 850°C for 1 min, 10 min, 30 min, 1 h, 1h30min and 10 h. Each heat treated sample and as received were tested using the electrochemical polarization reactivation of double loop technique (EPR-DL. It was possible the detection of deleterious phases with DL-EPR portable cell. The EPR-DL test of some samples showed a second peak of reactivation in which the results showed that this peak might be associated with ferrite or be related to the presence of chi phase

  8. Development of an automated informatic system, for the evaluation of damage in plastics and minerals; Desarrollo de un sistema informatico automatizado, para la evaluacion de danos en plasticos y minerales

    Energy Technology Data Exchange (ETDEWEB)

    Hidalgo V, V.; Lopez G, A.D.; Ledezma F, L.E.; Segovia R, A.; Balcazar, M. [ININ, 52750 La Marquesa, Estado de Mexico (Mexico)

    2008-07-01

    A computer system of pattern recognition to evaluate automatically the damages registered by positive ions in minerals and plastics was developed. In the case of minerals the apatite in which was achievement to recognize and to count the damages by spontaneous fission of the uranium contained in her was selected. The selected plastic was the CR39, in which was possible to obtain the distribution of the diameters of the you give you taken place by slight ions in this plastic. In both cases, the recognition of patterns you bases on Ision for Computer, using the methodology described by Gonzalez and Woods [6]. The technique consists in: Acquisition of the Image, Pre-prosecution, Segmentation, Description and Classification; the computer system you development making use of the software Matlab version 7. The Apatita you selects for their importance in the one dated geologic and the determination of the thermal history, both of importance in the oil prospecting. In the case of the CR39 their importance resides in its wide and massive use as dosimetro of neutrons, determination of environmental Radon and detection of nuclear reactions of low section. (Author)

  9. Study of the production of the radiopharmaceutical {sup 18}F-FLT in automated system: contribution for process validation; Estudo da producao do radiofarmaco FLT-{sup 18}F em sistema automatizado: contribuicao para a validacao do processo

    Energy Technology Data Exchange (ETDEWEB)

    Zanette, Camila

    2013-07-01

    Radiopharmaceutical {sup 18}F-FLT is a thymidine nucleoside analogue and a promising tumor proliferation marker for PET images. The synthesis of this radiopharmaceutical is not simple, and often has low yields. This radiopharmaceutical has already been studied for some years; however, there is no production, nor are there clinical studies in Brazil. The study of the production process and its compliance with the guidelines of Good Manufacturing Practices (ANVISA) are of extreme importance. This study aimed to investigate the synthesis of this radiopharmaceutical, evaluate methods of quality control that will be used in future production routines, perform cytotoxicity studies, biodistribution studies and PET imaging in animals, thereby contributing to the development and elaboration of the process validation protocol and to the establishment of analytical methods to be used during production routines. Initially, we studied the synthesis and production of {sup 18}F-FLT, with the evaluation of three different temperatures of radiolabeling to check the behavior of the radiochemical yield and stability of the nal product. Studies of analytical methodology comprised the analysis of radionuclide identification, determination of chromatographic profiles, radiochemical purity, residual solvents, and pH. In vitro studies of internalization and cytotoxicity were also carried out. In in vivo studies, we evaluated the pharmacokinetics, biodistribution in healthy animals and in animals with tumor models, in addition to PET/CT images in animals with melanomas. The final product had high radiochemical purity and was stable for up to 10 hours after the synthesis, but got a relatively low radiochemical yield, as described in the literature. The tested analytical methods proved suitable for use in the quality control of {sup 18}F-FLT. In in vitro studies, {sup 18}F-FLT showed a significant percentage of binding to tumor cells, and the nonradiolabeled molecule was not considered toxic for these studied cells. The biodistribution and images showed results that were consistent with expectations. Contributions to the validation process were satisfactory, and will assist in the future validation of the production process of the radiotracer under study. (author)

  10. 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%

  11. Implementation of the automated potentiometric titration method for total U at the CNEN Safeguard Laboratory, Brazil; Implementacao do metodo de titulacao potenciometrica automatizado para U total no Laboratorio de Salvaguardas da CNEN, Brasil

    Energy Technology Data Exchange (ETDEWEB)

    Cristiano, Barbara F.G.; Delgado, Jose U.; Araujo, Radier M.S. de; Silva, Jose W.S. da; Barros, Pedro D. de, E-mail: barbara@ird.gov.b [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2009-07-01

    Brazilian nuclear facilities, in accordance with the regulation CNEN-NN-2.02, must have available measurement systems which allow to determine their nuclear material inventories. For the evaluation and the follow up the performance of the involved laboratories in those measurement systems, the accomplishment of interlaboratory comparison programmes becomes fundamental. Therefore, the implementation of the potentiometric titration viewing the characterization of uranium samples, represents an reference element for the Brazilian programs

  12. Automated system for the management of the radiological safety in a radiopharmaceutical and labelled compounds production center; Sistema automatizado para la gestion de la seguridad radiologica un centro de produccion de radiofarmacos y compuestos marcados

    Energy Technology Data Exchange (ETDEWEB)

    Amador B, Z.H. [Centro de Isotopos, Ave. Monumental y Carretera La Rada, Km. 3, Guanabacoa, Apartado 3415, Ciudad de La Habana (Cuba); Alvarez Builla de Sologuren, E. [Centro de Gestion de Informacion y Desarrollo de la Energia, Cale 20 No. 4111 e/47y 18A, Playa, Ciudad de La Habana (Cuba)]. e-mail: zabalbona@centis.edu.cu

    2006-07-01

    The establishment in the Center of Isotopes of Cuba of a managerial quality system in matter of radiological safety Y the accumulated operational experience, its constitute the foundations for the development of a system of management of the radiological safety organically structured, with the application of evaluative techniques of it management Y it integration in an automated system. The Visual Basic 5 platform for the programming of the 'SASR' system is used. The functions of each one of the 11 modules that integrate it are described. With this it can be carried out the registration of the data of the training Y the personnel's authorization, the checkup of the radioactive inventory of the installation, the annual upgrade of the registrations of the individual doses of those workers, the analysis of the state of the available equipment for magnitude to control, the radiological situation of the work positions, the public exposure by the gassy discharges, the experiences of the radiological events, the annual consolidation of the costs of the safety Y the evaluation of indicators Y of tendencies. A computer tool that facilitates the effective management of the radiological safety in a radioactive installation is obtained. (Author)

  13. A simple automated procedure for thiol measurement in human serum samples Procedimento automatizado simples para determinação de tióis em amostras de soro humano

    OpenAIRE

    Carolina M. da Costa; Rita C. C. dos Santos; Emerson S. Lima

    2006-01-01

    Thiol groups have been described as the main responsible for antioxidative effects of plasmatic proteins. Also, thiol serum levels have shown a positive correlation with total antioxidant capacity (TAC) in many studies. Measurement of TAC by substract oxidation-based methods have been widely used as a reference to measure antioxidant status; however, in many cases these methods are inexact or imprecise, usually when performed by manual procedures. In this paper we describe a simple automated ...

  14. Methodology for monitoring and automated diagnosis of ball bearing using para consistent logic, wavelet transform and digital signal processing; Metodologia de monitoracao e diagnostico automatizado de rolamentos utilizando logica paraconsistente, transformada de Wavelet e processamento de sinais digitais

    Energy Technology Data Exchange (ETDEWEB)

    Masotti, Paulo Henrique Ferraz

    2006-07-01

    The monitoring and diagnosis area is presenting an impressive development in recent years with the introduction of new diagnosis techniques as well as with the use the computers in the processing of the information and of the diagnosis techniques. The contribution of the artificial intelligence in the automation of the defect diagnosis is developing continually and the growing automation in the industry meets this new techniques. In the nuclear area, the growing concern with the safety in the facilities requires more effective techniques that have been sought to increase the safety level. Some nuclear power stations have already installed in some machines, sensors that allow the verification of their operational conditions. In this way, the present work can also collaborate in this area, helping in the diagnosis of the operational condition of the machines. This work presents a new technique for characteristic extraction based on the Zero Crossing of Wavelet Transform, contributing with the development of this dynamic area. The technique of artificial intelligence was used in this work the Paraconsistent Logic of Annotation with Two values (LPA2v), contributing with the automation of the diagnosis of defects, because this logic can deal with contradictory results that the techniques of feature extraction can present. This work also concentrated on the identification of defects in its initial phase trying to use accelerometers, because they are robust sensors, of low cost and can be easily found the industry in general. The results obtained in this work were accomplished through the use of an experimental database, and it was observed that the results of diagnoses of defects shown good results for defects in their initial phase. (author)

  15. EPR spectra induced by gamma-irradiation of some dry medical herbs

    Science.gov (United States)

    Yordanov, N. D.; Lagunov, O.; Dimov, K.

    2009-04-01

    The radiation-induced EPR spectra in some medical herbs are reported. The samples studied are: (i) leaves of nettle, common balm, peppermint and thyme; (ii) stalks of common balm, thyme, milfoil, yarrow and marigold; (iii) blossoms of yarrow and marigold; (iv) blossoms and leaves of hawthorn and tutsan; and (v) roots of common valerian, nettle, elecampane (black and white), restharrows and carlina. Before irradiation all samples exhibit one weak anisotropic singlet EPR line with effective g-value of 2.0050±0.0002. The radiation-induced spectra fall into three groups. EPR spectra of irradiated blossoms of yarrow and marigold, stalks of common balm, thyme, tutsan and yarrow as well as roots of common valerian, nettle and elecampane (black and white) show "cellulose-like" EPR spectrum typical for irradiated plants. It is characterized by one intense central line with g=2.0050±0.0005 and two weak satellite lines situated ca. 30 G left and right to it. EPR spectra of gamma-irradiated restharrows and carlina are complex. They may be represented by one triplet corresponding to the "cellulose-like" EPR spectrum, one relatively intense singlet, situated in the center of the spectrum, and five weak additional satellite lines left and right to the center. The last spectrum was assigned as "carbohydrate-like" type. Only one intense EPR singlet with g=2.0048±0.0005 was recorded after irradiation of leaves of nettle and common balm. The lifetime of the radiation-induced EPR spectra was followed for a period of 3 months.

  16. Evaluation of the original dose in irradiated dried fruit by EPR spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    D' Oca, Maria Cristina, E-mail: mcristina.doca@unipa.it [Dipartimento Farmacochimico, Tossicologico e Biologico, Universita di Palermo, via Archirafi 32, 90123 Palermo (Italy); Bartolotta, Antonio [Dipartimento Farmacochimico, Tossicologico e Biologico, Universita di Palermo, via Archirafi 32, 90123 Palermo (Italy)

    2011-09-15

    The electron paramagnetic resonance spectroscopy (EPR) is one of the physical methods, recommended by the European Committee for Standardization, for the identification of irradiated food containing cellulose, such as dried fruit. In this work the applicability of EPR as identification method of irradiated pistachios, hazelnuts, peanuts, chestnuts, pumpkin seeds is evaluated; the time stability of the radiation induced signal is studied and the single aliquot additive dose method is used to evaluate the dose in the product.

  17. EPR spectra induced by gamma-irradiation of some dry medical herbs

    Energy Technology Data Exchange (ETDEWEB)

    Yordanov, N.D. [Laboratory EPR, Institute of Catalysis, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria)], E-mail: ndyepr@bas.bg; Lagunov, O. [Laboratory EPR, Institute of Catalysis, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria); Dimov, K. [Institute of Cryobiology and Food technology, 1162 Sofia (Bulgaria)

    2009-04-15

    The radiation-induced EPR spectra in some medical herbs are reported. The samples studied are: (i) leaves of nettle, common balm, peppermint and thyme; (ii) stalks of common balm, thyme, milfoil, yarrow and marigold; (iii) blossoms of yarrow and marigold; (iv) blossoms and leaves of hawthorn and tutsan; and (v) roots of common valerian, nettle, elecampane (black and white), restharrows and carlina. Before irradiation all samples exhibit one weak anisotropic singlet EPR line with effective g-value of 2.0050{+-}0.0002. The radiation-induced spectra fall into three groups. EPR spectra of irradiated blossoms of yarrow and marigold, stalks of common balm, thyme, tutsan and yarrow as well as roots of common valerian, nettle and elecampane (black and white) show 'cellulose-like' EPR spectrum typical for irradiated plants. It is characterized by one intense central line with g=2.0050{+-}0.0005 and two weak satellite lines situated ca. 30 G left and right to it. EPR spectra of gamma-irradiated restharrows and carlina are complex. They may be represented by one triplet corresponding to the 'cellulose-like' EPR spectrum, one relatively intense singlet, situated in the center of the spectrum, and five weak additional satellite lines left and right to the center. The last spectrum was assigned as 'carbohydrate-like' type. Only one intense EPR singlet with g=2.0048{+-}0.0005 was recorded after irradiation of leaves of nettle and common balm. The lifetime of the radiation-induced EPR spectra was followed for a period of 3 months.

  18. Use of polyphase continuous excitation based on the Frank sequence in EPR.

    OpenAIRE

    Tseitlin, Mark; Quine, Richard W.; Eaton, Sandra S.; Eaton, Gareth R.

    2011-01-01

    Polyphase continuous excitation based on the Frank sequence is suggested as an alternative to single pulse excitation in EPR. The method allows reduction of the source power, while preserving the excitation bandwidth of a single pulse. For practical EPR implementation the use of a cross-loop resonator is essential to provide isolation between the spin system and the resonator responses to the excitation. Provided that a line broadening of about 5% is acceptable, the cumulative turning angle o...

  19. EPR investigation of the dosimetric properties of collagen-alanine films

    International Nuclear Information System (INIS)

    The dosimetric properties of a new material consisting of collagen films containing alanine have been investigated in the range of 0.3-15 kGy absorbed dose. Within this domain the amplitude of the EPR line of the alanine radicals has increased linearity with the dose. After three months of storage at room temperature, the EPR spectra amplitude diminished by about 10%. (authors)

  20. Preparation and applicability of fresh fruit samples for the identification of radiation treatment by EPR

    Energy Technology Data Exchange (ETDEWEB)

    Yordanov, Nicola D. [Laboratory EPR, Institute of Catalysis, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria)], E-mail: ndyepr@bas.bg; Aleksieva, Katerina [Laboratory EPR, Institute of Catalysis, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria)

    2009-03-15

    The results of electron paramagnetic resonance (EPR) study on fresh fruits (whole pulp of pears, apples, peaches, apricots, avocado, kiwi and mango) before and after gamma-irradiation are reported using two drying procedures before EPR investigation. In order to remove water from non-irradiated and irradiated samples of the first batch, the pulp of fresh fruits is pressed, and the solid residue is washed with alcohol and dried at room temperature. The fruits of the second batch are pressed and dried in a standard laboratory oven at 40 deg. C. The results obtained with both drying procedures are compared. All samples under study show a singlet EPR line with g=2.0048{+-}0.0005 before irradiation. Irradiation gives rise to typical 'cellulose-like' EPR spectrum featuring one intensive line with g=2.0048{+-}0.0005 and two very weak satellite lines situated 3 mT at left and right of the central line. Only mango samples show a singlet line after irradiation. The fading kinetics of radiation-induced EPR signal is studied for a period of 50 days after irradiation. When the irradiated fruit samples are stored in their natural state and dried just before each EPR measurement, the satellite lines are measurable for less than 17 days of storage. Irradiated fruit samples, when stored dried, lose for 50 days ca. 40% of their radiation-induced radicals if treated with alcohol or ca. 70% if dried in an oven. The reported results unambiguously show that the presence of the satellite lines in the EPR spectra could be used for identification of radiation processing of fresh fruits, thus extending the validity of European Protocol EN 1787 (2000). Foodstuffs-Detection of Irradiated Food Containing Cellulose by EPR Spectroscopy. European Committee for Standardisation. Brussels for dry herbs.

  1. EPR Properties of Concentrated NdVO4 Single Crystal System

    OpenAIRE

    Kaczmarek, S.M.; Fuks, H.; Berkowski, M.; Głowacki, M.; Bojanowski, B.

    2015-01-01

    Single crystals of NdVO4 were grown by the Czochralski method under ambient pressure in a nitrogen atmosphere. Obtained crystals were transparent with strong violet coloring. Temperature and angular dependences of electron paramagnetic resonance (EPR) spectra of the samples in the 3–103 K temperature range were analyzed applying Dyson like lineshape typically used for concentrated magnetic system. EPR-NMR program was used to find local symmetry and spin-Hamiltonian parameters of neodymium ion...

  2. Pulsed EPR studies of small reactive radicals produced by ionizing radiation

    International Nuclear Information System (INIS)

    For several years we have participated in a collaborative research effort to apply the pulsed EPR-pulse radiolysis technique to several problems associated with the dynamics of small reactive radicals formed during radiolysis of aqueous solutions using 3 MeV electrons from a Van de Graaff accelerator. We will discuss experimental techniques and applications arising from this work, with particular emphasis on problems requiring high initial radical concentrations and EPR time resolution of one microsecond or better. 2 figs., 2 tabs

  3. Photosensitive EPR spectra of Pb-doped ZnS single crystals

    International Nuclear Information System (INIS)

    Photosensitive EPR investigations of lead-doped ZnS single crystals have been made. The results of excitation and quenching measurements are discussed in terms of the A-centre model, assuming a Zn vacancy associated with a neutral Pb2+ impurity on next cation site. A simple level model, involving the energetic positions of the photosensitive impurities in the band gap of ZnS, is proposed to explain the EPR excitation and quenching spectra. (author)

  4. Deterministic quantum key distribution based on Gaussian-modulated EPR correlations

    Institute of Scientific and Technical Information of China (English)

    He Guang-Qiang; Zeng Gui-Hua

    2006-01-01

    This paper proposes a deterministic quantum key distribution scheme based on Gaussian-modulated continuous variable EPR correlations. This scheme can implement fast and efficient key distribution. The security is guaranteed by continuous variable EPR entanglement correlations produced by nondegenerate optical parametric amplifier. For general beam splitter eavesdropping strategy, the secret information rate△I = I(α,β) - I(α,ε) is calculated in view of Shannon information theory. Finally the security analysis is presented.

  5. EPR spectra induced by gamma-irradiation of some dry medical herbs

    International Nuclear Information System (INIS)

    The radiation-induced EPR spectra in some medical herbs are reported. The samples studied are: (i) leaves of nettle, common balm, peppermint and thyme; (ii) stalks of common balm, thyme, milfoil, yarrow and marigold; (iii) blossoms of yarrow and marigold; (iv) blossoms and leaves of hawthorn and tutsan; and (v) roots of common valerian, nettle, elecampane (black and white), restharrows and carlina. Before irradiation all samples exhibit one weak anisotropic singlet EPR line with effective g-value of 2.0050±0.0002. The radiation-induced spectra fall into three groups. EPR spectra of irradiated blossoms of yarrow and marigold, stalks of common balm, thyme, tutsan and yarrow as well as roots of common valerian, nettle and elecampane (black and white) show 'cellulose-like' EPR spectrum typical for irradiated plants. It is characterized by one intense central line with g=2.0050±0.0005 and two weak satellite lines situated ca. 30 G left and right to it. EPR spectra of gamma-irradiated restharrows and carlina are complex. They may be represented by one triplet corresponding to the 'cellulose-like' EPR spectrum, one relatively intense singlet, situated in the center of the spectrum, and five weak additional satellite lines left and right to the center. The last spectrum was assigned as 'carbohydrate-like' type. Only one intense EPR singlet with g=2.0048±0.0005 was recorded after irradiation of leaves of nettle and common balm. The lifetime of the radiation-induced EPR spectra was followed for a period of 3 months

  6. Automation of the ERS-231 epr spectrometer on the basis of an IBM PC computer

    International Nuclear Information System (INIS)

    Paper describes a computer-aided control system (CCS) of a EPR spectrometer based on dataway-module measuring and computering system incorporating crates for functional modules and IBM PC computer. Paper contains CCS flow-diagram based on EPR for ERS-231 spectrometer. The spectrometer software consists of MS DOS operated text and control programs. Abilities of the updated spectrometer were checked using various specimens and under various temperatures

  7. The effects of beam quality on EPR spectra and alanine dosimetry in mixed radiation fields

    International Nuclear Information System (INIS)

    Sensitization of L-Alanine dosimetry to neutrons showed that variations in the beam quality, resulting from adding boric acid to L-Alanine samples, affected the intensity and the shape of the lines in the EPR spectra of alanine following irradiation with thermal neutrons. Disintegration of 10B in the (n, α) process, enhances the EPR signal due to increase in the local dose deposition. The relative effectiveness of alanine dosimetry to neutrons was found to be about 0.5. (author)

  8. New Developed Cylindrical TM010 Mode EPR Cavity for X-Band In Vivo Tooth Dosimetry

    OpenAIRE

    Junwang, Guo; Qingquan, Yuan; Jianbo, Cong; Lei, Ma; Guofu, Dong; Guoshan, Yang; Ke, Wu

    2014-01-01

    EPR tooth in vivo dosimetry is an attractive approach for initial triage after unexpected nuclear events. An X-band cylindrical TM010 mode resonant cavity was developed for in vivo tooth dosimetry and used in EPR applications for the first time. The cavity had a trapezoidal measuring aperture at the exact position of the cavity’s cylindrical wall where strong microwave magnetic field H1 concentrated and weak microwave electric field E1 distributed. Theoretical calculations and simulations wer...

  9. Chitosan gallate as a novel potential polysaccharide antioxidant: an EPR study

    OpenAIRE

    Pasanphan, Wanvimol; Buettner, Garry R.; Chirachanchai, Suwabun

    2009-01-01

    A novel biopolymer-based antioxidant, chitosan conjugated with gallic acid (chitosan galloylate, chitosan– GA), is proposed. Electron paramagnetic resonance (EPR) demonstrates a wide range of antioxidant activity for chitosan–GA as evidenced from its reactions with oxidizing free radicals, that is, 1,1-diphenyl-2-picryl-hydrazyl (DPPH), horseradish peroxidase (HRP)–H2O2, carbon-centered alkyl radicals, and hydroxyl radicals. The EPR spectrum of the radical formed on chitosan–GA was attributed...

  10. Structural Characterization of Polymer-Clay Nanocomposites Prepared by Co-Precipitation Using EPR Techniques

    OpenAIRE

    Udo Kielmann; Gunnar Jeschke; Inés García-Rubio

    2014-01-01

    Polymer-clay nanocomposites (PCNCs) containing either a rubber or an acrylate polymer were prepared by drying or co-precipitating polymer latex and nanolayered clay (synthetic and natural) suspensions. The interface between the polymer and the clay nanoparticles was studied by electron paramagnetic resonance (EPR) techniques by selectively addressing spin probes either to the surfactant layer (labeled stearic acid) or the clay surface (labeled catamine). Continuous-wave (CW) EPR studies of th...

  11. Preparation and applicability of fresh fruit samples for the identification of radiation treatment by EPR

    International Nuclear Information System (INIS)

    The results of electron paramagnetic resonance (EPR) study on fresh fruits (whole pulp of pears, apples, peaches, apricots, avocado, kiwi and mango) before and after gamma-irradiation are reported using two drying procedures before EPR investigation. In order to remove water from non-irradiated and irradiated samples of the first batch, the pulp of fresh fruits is pressed, and the solid residue is washed with alcohol and dried at room temperature. The fruits of the second batch are pressed and dried in a standard laboratory oven at 40 deg. C. The results obtained with both drying procedures are compared. All samples under study show a singlet EPR line with g=2.0048±0.0005 before irradiation. Irradiation gives rise to typical 'cellulose-like' EPR spectrum featuring one intensive line with g=2.0048±0.0005 and two very weak satellite lines situated 3 mT at left and right of the central line. Only mango samples show a singlet line after irradiation. The fading kinetics of radiation-induced EPR signal is studied for a period of 50 days after irradiation. When the irradiated fruit samples are stored in their natural state and dried just before each EPR measurement, the satellite lines are measurable for less than 17 days of storage. Irradiated fruit samples, when stored dried, lose for 50 days ca. 40% of their radiation-induced radicals if treated with alcohol or ca. 70% if dried in an oven. The reported results unambiguously show that the presence of the satellite lines in the EPR spectra could be used for identification of radiation processing of fresh fruits, thus extending the validity of European Protocol EN 1787 (2000). Foodstuffs-Detection of Irradiated Food Containing Cellulose by EPR Spectroscopy. European Committee for Standardisation. Brussels for dry herbs

  12. Transport de paires EPR dans des structures mesoscopiques

    Science.gov (United States)

    Dupont, Emilie

    Dans cette these, nous nous sommes particulierement interesses a la propagation de paires EPR1 delocalisees et localisees, et a l'influence d'un supraconducteur sur le transport de ces paires. Apres une introduction de cette etude, ainsi que du cadre scientifique qu'est l'informatique quantique dans lequel elle s'inscrit, nous allons dans le chapitre 1 faire un rappel sur le systeme constitue de deux points quantiques normaux entoures de deux fils supraconducteurs. Cela nous permettra d'introduire une methode de calcul qui sera reutilisee par la suite, et de trouver egalement le courant Josephson produit par ce systeme transforme en SQUID-dc par l'ajout d'une jonction auxiliaire. Le SQUID permet de mesurer l'etat de spin (singulet ou triplet), et peut etre forme a partir d'autres systemes que nous etudierons ensuite. Dans le chapitre 2, nous rappellerons l'etude detaillee d'un intricateur d'Andreev faite par un groupe de Bale. La matrice T, permettant d'obtenir le courant dans les cas ou les electrons sont separes spatialement ou non, sera etudiee en detail afin d'en faire usage au chapitre suivant. Le chapitre 3 est consacre a l'etude de l'influence du bruit sur le fonctionnement de l'intricateur d'Andreev. Ce bruit modifie la forme du courant jusqu'a aboutir a d'autres conditions de fonctionnement de l'intricateur. En effet, le bruit present sur les points quantiques peut perturber le transport des paires EPR par l'intermediaire des degres de liberte. Nous montrerons que, du fait de l'"intrication" entre la charge de la paire et le bruit, la paire est detruite pour des temps longs. Cependant, le resultat le plus important sera que le bruit perturbe plus le transport des paires delocalisees, qui implique une resonance de Breit-Wigner a deux particules. Le transport parasite n'implique pour sa part qu'une resonance de Breit-Wigner a une particule. Dans le chapitre 4, nous reviendrons au systeme constitue de deux points quantiques entoures de deux fils

  13. EPR safety. Consideration of the internal and external hazards in the safety studies; Surete du reacteur EPR. Prise en compte des agressions internes et externes dans les etudes de surete EPR

    Energy Technology Data Exchange (ETDEWEB)

    Gueguin, H. [Electricite de France (EDF-DIN), Centre National d' Equipement Nucleaire, Service Controle Commande, 92 - Montrouge (France)

    2008-04-15

    The author presents the main points of the Preliminary Safety Report of EDF on the EPR reactor safety. It concerns the considerations of the internal (fire, flood, explosions, pipes failures) and external (earthquakes, airplane falls, explosions, exceptional natural disasters, extreme meteorological conditions) damages. It presents how the safety report takes into account the aggression. (A.L.B.)

  14. EPR and IR spectral investigations on some leafy vegetables of Indian origin

    Science.gov (United States)

    Prasuna, C. P. Lakshmi; Chakradhar, R. P. S.; Rao, J. L.; Gopal, N. O.

    2009-09-01

    EPR spectral investigations have been carried out on four edible leafy vegetables of India, which are used as dietary component in day to day life. In Rumex vesicarius leaf sample, EPR spectral investigations at different temperatures indicate the presence of anti-ferromagnetically coupled Mn(IV)-Mn(IV) complexes. EPR spectra of Trigonella foenum graecum show the presence of Mn ions in multivalent state and Fe 3+ ions in rhombic symmetry. EPR spectra of Basella rubra indicate the presence of Mn(IV)-O-Mn(IV) type complexes. The EPR spectra of Basella rubra have been studied at different temperatures. It is found that the spin population for the resonance signal at g = 2.06 obeys the Boltzmann distribution law. The EPR spectra of Moringa oliefera leaves show the presence of Mn 2+ ions. Radiation induced changes in free radical of this sample have also been studied. The FT-IR spectra of Basella rubra and Moringa oliefera leaves show the evidences for the protein matrix bands and those corresponding to carboxylic C dbnd O bonds.

  15. VHF EPR analysis of organic sulfur in coal. Technical report, December 1, 1992--February 28, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Clarkson, R.B.; Belford, R.L. [Illinois Univ., Urbana, IL (United States); Ho, K. [Illinois Clean Coal Inst., Carterville, IL (United States)

    1993-05-01

    One important goal of this project is the development of methods to analyze the Very High Frequency Electron Paramagnetic Resonance (VHF EPR) spectra from Illinois coals in order to determine the concentration of organic sulfur in them. We have begun that development work, utilizing a two-species, axially symmetric model for the simulation of VHF EPR coal spectra. Such a model provides quantitative information on the concentration of sulfur species that can be directly related to the organic sulfur content as measured by more conventional chemical methods. The computer modeling technique which we are developing makes use of a multi-dimensional simplex strategy for optimization. Utilizing our newly developed method, we have analyzed the VHF EPR spectra from several sub-bituminous coals containing organic sulfur in the range from 2% to 12%. Excellent quantitative agreement is achieved between VHF EPR results and chemical analyses. In addition to providing information on the concentration of organic sulfur present in coal, the analysis of VHF EPR spectra also provides detailed spectral parameters. These parameters are related to the molecular structures giving rise to the EPR signals.

  16. Study on the EPR/dosimetric properties of some substituted alanines

    International Nuclear Information System (INIS)

    Polycrystalline phenyl-alanine and perdeuterated l-α-alanine (l-α-alanine-d4) were studied as potential high-energy radiation-sensitive materials (RSM) for solid state/EPR dosimetry. It was found that phenyl-alanine exhibits a linear dose response in the dose region 0.1-17kGy. However, phenyl-alanine is about 10 times less sensitive to γ-irradiation than standard l-α-alanine irradiated at the same doses. Moreover, the EPR response from phenyl-alanine is unstable and, independent of the absorbed dose, decreases by about 50% within 20 days after irradiation upon storage at room temperature. γ-irradiated polycrystalline perdeuterated l-α-alanine (CD3CD(NH2)COOH) has not previously been studied at room temperature by EPR spectroscopy. The first part of the present analysis was with respect to the structure of the EPR spectrum. By spectrum simulations, the presence of at least two radiation induced free radicals, R1=CH3C*(H)COOH and R2=H3N+-C*(CH3)COO-, was confirmed very clearly. Both these radicals were suggested previously from EPR and ENDOR studies of standard alanine crystals. The further investigations into the potential use of alanine-d4 as RSM, after choosing optimal EPR spectrometer settings parameters for this purpose, show that it is ca. two times more sensitive than standard l-α-alanine

  17. The study of intergranular corrosion of sensitized alloy 600 using DL-EPR and Huey method

    Energy Technology Data Exchange (ETDEWEB)

    Rhee, Chang Kyu; Kuk, Il Hyun; Ryu, Woo Seok [Korea Atomic Energy Research Institute, Taejon (Korea)

    1999-03-01

    Intergranular corrosion(IGC) of sensitized Alloy 600 has been studied with double loop-electrochemical potentiokinetic reactivation (DL-EPR) and Huey test. Corrosion of solution annealed Ni-XCr-10Fe(X=6 {approx} 15) alloys was also evaluated with DL-EPR and Huey method to simulate corrosion of Cr depleted grain boundary region of Alloy 600. Cr concentration profile across grain boundary was measured with TEM. In the range of the Cr concentration from 6 to 8%, corrosion rate of solution annealed Ni-XCr-10Fe(X=6 {approx} 15) alloys were much higher in Huey test than in DL-EPR. But in the range of the Cr concentration from 12 to 15%, the trend were reversed. The width of IGC crack of Alloy 600 was higher in DL-EPR test than in Huey test in agreement with corrosion of solution annealed Ni-XCr-10Fe alloys. Width of IGC along depth produced by DL-EPR test was almost uniform and wide while that produced by Huey test was sharp and narrow. These results suggest that IGC in DL-EPR test proceeds following uniform dissolution model and IGC in Huey test proceeds following Cr concentration dependent dissolution model. (author). 22 refs., 23 figs., 4 tabs.

  18. Using ANN and EPR models to predict carbon monoxide concentrations in urban area of Tabriz

    Directory of Open Access Journals (Sweden)

    Mohammad Shakerkhatibi

    2015-09-01

    Full Text Available Background: Forecasting of air pollutants has become a popular topic of environmental research today. For this purpose, the artificial neural network (AAN technique is widely used as a reliable method for forecasting air pollutants in urban areas. On the other hand, the evolutionary polynomial regression (EPR model has recently been used as a forecasting tool in some environmental issues. In this research, we compared the ability of these models to forecast carbon monoxide (CO concentrations in the urban area of Tabriz city. Methods: The dataset of CO concentrations measured at the fixed stations operated by the East Azerbaijan Environmental Office along with meteorological data obtained from the East Azerbaijan Meteorological Bureau from March 2007 to March 2013, were used as input for the ANN and EPR models. Results: Based on the results, the performance of ANN is more reliable in comparison with EPR. Using the ANN model, the correlation coefficient values at all monitoring stations were calculated above 0.85. Conversely, the R2 values for these stations were obtained <0.41 using the EPR model. Conclusion: The EPR model could not overcome the nonlinearities of input data. However, the ANN model displayed more accurate results compared to the EPR. Hence, the ANN models are robust tools for predicting air pollutant concentrations.

  19. OSSA - An optimized approach to severe accident management: EPR application

    International Nuclear Information System (INIS)

    There is a recognized need to provide nuclear power plant technical staff with structured guidance for response to a potential severe accident condition involving core damage and potential release of fission products to the environment. Over the past ten years, many plants worldwide have implemented such guidance for their emergency technical support center teams either by following one of the generic approaches, or by developing fully independent approaches. There are many lessons to be learned from the experience of the past decade, in developing, implementing, and validating severe accident management guidance. Also, though numerous basic approaches exist which share common principles, there are differences in the methodology and application of the guidelines. AREVA/Framatome-ANP is developing an optimized approach to severe accident management guidance in a project called OSSA ('Operating Strategies for Severe Accidents'). There are still numerous operating power plants which have yet to implement severe accident management programs. For these, the option to use an updated approach which makes full use of lessons learned and experience, is seen as a major advantage. Very few of the current approaches covers all operating plant states, including shutdown states with the primary system closed and open. Although it is not necessary to develop an entirely new approach in order to add this capability, the opportunity has been taken to develop revised full scope guidance covering all plant states in addition to the fuel in the fuel building. The EPR includes at the design phase systems and measures to minimize the risk of severe accident and to mitigate such potential scenarios. This presents a difference in comparison with existing plant, for which severe accidents where not considered in the design. Thought developed for all type of plants, OSSA will also be applied on the EPR, with adaptations designed to take into account its favourable situation in that field

  20. EPR of transition metal ions in NZP ceramics

    International Nuclear Information System (INIS)

    NZP-ceramics have been produced by different methods such as sol-gel, flux melting and sintering of dry salts or phosphates. Formation of NZP and related phases was confirmed by X-ray diffraction analysis. Electron paramagnetic resonance (EPR) was applied to evaluate a structure positions of paramagnetic ions and nature of radiation-induced centers. EPR responses from transition metal ions Fe3+ and Mn2+ with electron configuration 3d5 (ground state 6S5/2) which occurred as impurities in raw materials were registered in powders of NZP-ceramics. Fine structure arising due to high spin iron complexes is well resolved. A part of Fe3+ ions substitutes for Zr4+ and another part of one substitutes for Na+ ions in six-fold coordinated positions. A great value of hyperfine structure (hfs) constant (9.3 mT) shows a high ionic character of Mn-O bonds in the first coordination sphere. A coordination number is close to 6. Fine structure of Mn2+ ions are not well resolved. A comparison of the spectra of samples containing various alkali cations shows the substitution for cations in series of Li-Na-K-Rb-Cs does not result in fundamental variation in spectra except for CZP ceramics where the response with g=4.3 due to Fe3+ in strong ligand field rather than response with g=2.0 due to Fe3+ in weak field is observed. An investigation of some samples doped by 0.1...0.5 mole % of Fe3+ or Gd3+ has been carried out and principal spin-Hamiltonian parameters have been determined. The increase of Fe and Gd ions content as compared to impurity substituting for Zr and possibly Na in their own structural positions results in noticeable site distortion. Gamma irradiation of NZP ceramics results in formation of radiation-induced paramagnetic centers connected to phosphorus-oxygen. The nature and concentration of these centers depend on production method. The lowest defect concentration is in hot-pressed ceramics

  1. The EPR-a comprehensive design concept against external events

    International Nuclear Information System (INIS)

    The main objective of design provisions against external hazards is to ensure that the safety functions required to bring the plant to safe shutdown are not inadmissible affected. In the design of the EPR particular attention was paid to the following external hazards: Earthquake, Airplane crash, Explosion pressure wave. The design concept for these events is discussed below. The standard EPR covers a large range of possible site conditions, the design earthquake enveloping safe shutdown earthquakes (SSE) to be expected for potential sites. The Basic Design was developed for the seismic loads given in the European Utility Requirements with a horizontal free field Peak Ground Acceleration (PGA) for all site conditions of 0.25 g. The seismic protection is based on a deterministic design approach, with the intention of ensuring the safety functions in case of SSE. The loads for the design basis airplane crash and - if required - for the design extension airplane crash are defined depending on site specific requirements. For the design basis airplane crash as defined in Finland the safety goals are fulfilled for postulated single failure and preventive maintenance as well as for specific unlikely scenarios with local impacts where one redundant train is assumed to be lost. For the design extension airplane crash no single failure and preventive maintenance are assumed. Reactor building (RB), fuel building (FB), safeguard building (SB) 2 and 3 are protected by design against airplane crash. The common base mat of the RB, FB and SBs ensures global stability. To avoid penetration the wall thickness of the outer building structures of RB, FB and SB2/3 is set at 1.80 m (result of an optimization process). To rule out major induced vibrations due to airplane crash the inner building structures are decoupled from the outer walls. The SB 1 and SB4, the main steam and feedwater valve compartments, the diesel buildings and the service water pump buildings are protected against

  2. Aplicación del formato Dublin Core para la descripción de los recursos en la biblioteca virtual del CDICT- Universidad Central de Las Villas (Cuba

    Directory of Open Access Journals (Sweden)

    Lic. Ramón A. Manso Rodríguez

    2002-01-01

    Full Text Available Tomando en consideración el aumento de literatura en soporte electrónico y como parte del desarrollo de sus sistemas automatizados de gestión bibliotecaria, el Centro de Documentación e Información Científico – Técnica de la Universidad Central de Las Villas, Santa Clara, Cuba, construyó su biblioteca virtual utilizando los campos especificados en el formato Dublin Core, para la descripción de los recursos que se le incorporarían al sistema. En este trabajo damos una breve panorámica de la utilización del mismo, además de un análisis conceptual sobre el termino biblioteca virtual

  3. EPR characterisation of platinum nanoparticle functionalised carbon nanotube hybrid materials.

    Science.gov (United States)

    Dennany, Lynn; Sherrell, Peter; Chen, Jun; Innis, Peter C; Wallace, Gordon G; Minett, Andrew I

    2010-04-28

    The use of nanostructured carbon materials as electrodes for energy storage and conversion is an expanding area of research in recent years. Herein, platinum nanoparticles have been deposited onto both multi-walled and single-walled carbon nanotubes (CNTs) via a microwave assisted polyol reduction method. This interaction has been probed with electron paramagnetic resonance (EPR) and Raman spectroscopies to elucidate the charge/electron transfer interactions between the Pt nanoparticles and the CNTs. Observed shifts in the g factors of the CNTs are indicative of such an electronic interaction, strongly suggesting the covalent attachment of the nanoparticles to the carboxylic groups on the CNTs, formed during the microwave-assisted reduction process. The Pt decorated CNTs show a dramatic increase in electrochemical behaviour in terms of high reversible capacity and relatively stable cycle performance compared to unmodified CNTs increasing their applicability in energy storage devices. For instance, significant increases in the electrochemical double layer capacitance are observed for the CNT-NP composite electrode. PMID:20379504

  4. The EPR concept for serious accident management, and accompanying research

    International Nuclear Information System (INIS)

    An accident, even if the probability of occurrence is so low that it can practically be excluded, must not require any serious external emergency measures, such as evacuation of human populations outside the immediate neighbourhood of the plant. This demand, which in the meantime has also become part of the German article law, creates a new situation for future light water reactors. In addition to the measures which are to reduce the probability of occurrence of serious accidents, a level is introduced which is designed to control the consequences of serious accidents with postulated core meltdown. The introduction of specific measures and design characteristics is a new challenge which cannot be met by industry alone. It is necessary to resort, to a large extent, to present and future research and development work which has been and will be carried out in this area by large-scale research institutions and universities. As regards the EPR, research and development cooperation in this field has been intensified recently. The CEA research centres and the FZKA signed an agreement on information exchange. (orig./HP)

  5. EPR spectroscopic analysis of TAR RNA-metal ion interactions

    International Nuclear Information System (INIS)

    Metal ion-induced changes in HIV-1 TAR RNA internal dynamics were determined by the changes in EPR spectral width for TAR RNAs containing spin-labeled nucleotides (U23, U25, U38, and U40). This gave a dynamic signature for each of 10 metal ions studied, which fell into one of three distinct groups. While Li+ and K+ had little effect on TAR RNA internal dynamics, Na+ unexpectedly had a dynamic signature that was similar to Ca2+ and Sr2+, with a decrease in mobility at U23 and U38, little or no change at U25, and an increase in mobility at U40. Mg2+, Co2+, Ni2+, Zn2+, and Ba2+ had similar effects on U23, U38, and U40, but the mobility of U25 was markedly increased. Our results show that RNA dynamics change upon metal binding to the TAR RNA bulge, indicating that RNA structure adapts to accommodate metal ions of different size and coordination properties

  6. Propuesta para la optimización de asientos catalográficos en catálogos en línea de primera generación

    Directory of Open Access Journals (Sweden)

    Jiménez Pelayo, Jesús J.

    1997-03-01

    Full Text Available Development and consolidation of automated environment in libraries affect specially the capacity of the present cataloguing standards: they are in question both technologically and economically. Some agencies and professionals claim for an urgent reevaluation and/or modification of those standards in order to suit them in a synchronized way to the new environment and its needs. The following proposal for the optimization of first generation online catalogues tries to unify the different institutional projects for establishment of simplified ISBD standards and MARC formats, as well as the results of occasional studies and researches on cataloguing codification. A feasible solution of immediate application for definitive transition from card catalogue lo automated catalogue is offered.

    El desarrollo y consolidación de los entornos automatizados en el ámbito de las bibliotecas afecta de manera decisiva a la funcionalidad de los estándares catalográficos vigentes y los cuestiona tanto tecnológica como económicamente. Algunas agencias y profesionales reclaman una urgente reevaluación y/o modificación de dichos estándares con objeto de adaptarlos, de forma sincronizada, al nuevo marco y sus necesidades. La siguiente propuesta para la optimización de catálogos en línea de primera generación surge de un intento de aunar los distintos proyectos institucionales en curso para el establecimiento de normas ISBD y formatos MARC simplificados, así como los resultados de estudios e investigaciones puntuales en el campo de la codificación catalográfica. Se pretende con ello ofrecer una solución viable y de aplicación inmediata a la transición definitiva catálogo manual-catálogo automatizado.

  7. Electron paramagnetic resonance (EPR) study of DOPA–melanin complexes with kanamycin and copper(II) ions

    OpenAIRE

    Najder-Kozdrowska, Lidia; Pilawa, Barbara; Buszman, Ewa; Wrzesniok, Dorota; Więckowski, Andrzej B.

    2011-01-01

    This work comprises the study of DOPA–melanin complexes with kanamycin and copper(II) ions made by electron paramagnetic resonance EPR spectroscopy. The high concentration of paramagnetic centers in melanin makes the use of EPR spectroscopy possible. The unpaired electron localized on the oxygen atom in indol-5,6-quinone groups is the paramagnetic centers in this polymer. The aim of this work was the analysis of EPR parameters of recorded spectra. For researches were prepared melanin complexe...

  8. Electronically Tunable Surface-Coil-Type Resonator for L-Band EPR Spectroscopy

    Science.gov (United States)

    Hirata, Hiroshi; Walczak, Tadeusz; Swartz, Harold M.

    2000-01-01

    The automatic frequency control (AFC) circuit in conventional electron paramagnetic resonance (EPR) spectrometers automatically tunes the microwave source to the resonance frequency of the resonator. The circuit works satisfactorily for samples stable enough that the geometric relations in the resonance structure do not change in a significant way. When EPR signals are measured during in vivo experiments with small rodents, however, the distance between the signal source and the surface-coil detector can change rapidly. When a conventional AFC circuit keeps the oscillator tuned to the resonator under those conditions, the resultant frequency change may exceed ±5 MHz and markedly shift the position of the EPR signal. Such a shift results in unacceptable effects on the spectra, especially when the experimenter is dealing with narrow EPR lines. The animal movement also causes a mismatching of the resonator and the 50-ohm transmission line. Direct results of this mismatching are increased noise; shifts in the position of the baseline; and a high probability of overdriving the signal preamplifier with consequent loss of the EPR signal. We therefore designed, built, and tested a new surface-coil resonator using varactor diodes for tuning the resonance frequency to the fixed frequency oscillator and for capacitive matching of the resonator to the 50-ohm transmission line. The performance of the automatic matching system was tested in vivo by measuring EPR spectra of lithium phthalocyanine implanted in rats. Stability and sensitivity of the spectrometer were evaluated by measuring EPR spectra with and without the use of the automatic matching system. The overall experimental performance of the spectrometer was found to significantly improve during in vivo experiments using the automatic matching system. Excellent matching between the 50-ohm transmission line and the resonator was maintained under all experimental circumstances that were tested. This should allow us now to

  9. Solución informática del subsistema de sincronización para centros de gestion de emergencias

    Directory of Open Access Journals (Sweden)

    Eddy Sánchez Téllez

    2011-10-01

    Full Text Available Los centros de gestión de emergencias tienen como finalidad la recepción de las llamadas de auxilio y su gestión ante los servicios oportunos, realizando un seguimiento de la evolución de la emergencia hasta su cierre. Estos centros poseen sistemas automatizados de gestión de emergencias para agilizar el proceso de atención a las solicitudes de la población. El sistema de gestión de emergencias propuesto es distribuido con una base de datos centralizada, cuyos subsistemas se comunican a través de una LAN, la cual no debe permitir accesos desde internet ni comunicación con redes exteriores. Está constituido por varios subsistemas que comparten información, por lo que necesitan comunicarse constantemente para trabajar con los datos actualizados y llevar a cabo la atención a las solicitudes realizadas por la población de forma eficiente. Para garantizar la coherencia y actualización de la información en varios subsistemas cuyos datos son críticos para la garantía de la vida humana se propone diseñar mecanismos informáticos de sincronización.

  10. Módulo de Visualización para el análisis petrofísico a pozos de petróleo

    Directory of Open Access Journals (Sweden)

    Ridel Oscar García Mora

    2014-07-01

    Full Text Available El petróleo es un recurso natural no renovable utilizado para producir un alto porcentaje de la energía que se consume en el mundo. Debido a su importancia y utilidad se extrae en casi todos los países de América. En Cuba se utilizan para la exploración de este preciado recurso, sistemas automatizados, que entre sus características permiten analizar, evaluar y modificar la información contenida en los archivos de registros de pozos de petróleo. Estos sistemas automatizados son una gran ayuda en el análisis e interpretación de la información contenida en los registros de pozos, proporcionando una mayor precisión y velocidad en el procesamiento. Pero para Cuba, el uso de estos sistemas no es factible debido al elevado costo requerido para utilizarlos, además, que sólo se pueden ejecutar en el sistema operativo Windows. El presente trabajo tiene el objetivo de permitir el análisis de la información contenida en los archivos de registros de pozo de petróleo a través de la visualización de histogramas, cross-plot y pistas. Para desarrollar este trabajo se emplearon los métodos científicos: analítico-sintético, modelado, observación y entrevista. Además, se utilizó la metodología RUP, lenguaje de modelado UML, la herramienta CASE Visual Paradigm, el lenguaje de programación C++ y el marco de desarrollo Qt, como entorno de desarrollo QT Creator y la biblioteca Qwt5. Como resultado de este trabajo, además del módulo implementado, se obtuvo la ingeniería de requisitos y análisis del modelo de negocio de la información contenida en los registros de pozos de petróleo.

  11. EPR study of deoxygenated high-temperature superconductors

    Indian Academy of Sciences (India)

    R J Singh; P K Sharma; Shakeel Khan

    2002-05-01

    High-c superconductors are EPR silent but on a little deoxygenation of the high-c materials and their constituents, they yield rich but complex spectra. Spectra of (1) CuO, (2) BaCuO2, (3) CaCuO2, (4) Y2Cu2O5, (5) La2CuO4, (6) La2-CuO4 (M = Sr, Ba), (7) Y based-123, (8) Bi based-2201, 2212, 2223, (9) Tl based-2223 and (10) Hg based-1212,1223 have been studied. One thing common to all these materials is the CuO2 plane which gets fragmented on deoxygenation and the inherent antiferromagnetic coupling is partially destroyed which results in the appearance of the spectra. The spectra recorded have been identified to be due to (1) Cu-monomer, (2) Cu-dimer, (3) Cutetramer, (4) Cu-octamer and (5) one signal at very low field which could not be identified because there was no structure in it and may be due to fragments higher than octamers. Very big fragments do not give any spectra because the original AF order probably remains intact in them. It is expected that when the fragments become magnetically isolated from the bulk, they produce EPR spectra. Most of the spectra have been analyzed and their spin-Hamiltonian parameters determined. The spectra of these species vary a little in terms of g-value and fine-structure splitting constant from sample to sample or even in the same sample and this may be attributed to some extra oxygen attachments retained with these species. Most frequently occurring species is the Cu-tetramer, (CuO)4. As (CuO)4 represents the unit cell of the all important two-dimensional CuO2 plane of the high-c materials, its spectra have been argued to provide some clue to the mechanism of high-c superconductivity. The tetramer (CuO)4 is a four one-half spin system and is essentially 16-fold degenerate by Heisenberg isotropic exchange, it is split into 6 components: one pentet, three triplets and two singlets. In superconductors the pentet appears to be the ground state and in the non-superconducting constituents the singlets seem to form the ground

  12. Superconducting magnet systems for the ANL EPR design

    International Nuclear Information System (INIS)

    The magnet systems for the current Argonne experimental power reactor (EPR) design build on the earlier designs but incorporate a number of improvements. The toroidal field (TF) coil system consists of 16 coils of the constant tension shape, with NbTi, copper, and stainless steel as superconductor, stabilizer, and support material respectively. They are designed for 10 T operation at 3.7 K or 9 T operation at 4.2 K. Two changes from earlier designs permit a saving in material requirements. The coils are wound with the conductor in precompression and the support material in pretension so that when the coils are energized, the stainless steel experiences a stress of 60,000 psi while the copper stress does not exceed 15,000 psi. Both the copper and NbTi are graded, with higher current densities where magnetic and radiation effects are smaller. The ohmic heating (OH) coil system consists of a central solenoid plus ten other coils, all located outside the TF coils for ease of maintenance. The NbTi-copper coils are cryostable and operate at 4.2 K. The solenoid is segmented, with rings of insulation between segments to transfer the centering force from the TF coils to an insulating cylinder inside the OH solenoid. Locating the OH solenoid inside the support cylinder plus raising the central field to 8 T, enables the OH system to develop more volt-seconds than the earlier designs, even though the plasma major radius is smaller. The superconducting equilibrium field coils, also outside the TF coils, provide the field pattern required for a D-shaped plasma

  13. EPR/alanine dosimetry for two therapeutic proton beams

    Science.gov (United States)

    Marrale, Maurizio; Carlino, Antonio; Gallo, Salvatore; Longo, Anna; Panzeca, Salvatore; Bolsi, Alessandra; Hrbacek, Jan; Lomax, Tony

    2016-02-01

    In this work the analysis of the electron paramagnetic resonance (EPR) response of alanine pellets exposed to two different clinical proton beams employed for radiotherapy is performed. One beam is characterized by a passive delivery technique and is dedicated to the eyes treatment (OPTIS2 beam line). Alanine pellets were irradiated with a 70 MeV proton beam corresponding to 35 mm range in eye tissue. We investigated how collimators with different sizes and shape used to conform the dose to the planned target volume influence the delivered dose. For this purpose we performed measurements with varying the collimator size (Output Factor) and the results were compared with those obtained with other dosimetric techniques (such as Markus chamber and diode detector). This analysis showed that the dosimeter response is independent of collimator diameter if this is larger than or equal to 10 mm. The other beam is characterized by an active spot-scanning technique, the Gantry1 beam line (maximum energy 230 MeV), and is used to treat deep-seated tumors. The dose linearity of alanine response in the clinical dose range was tested and the alanine dose response at selected locations in depth was measured and compared with the TPS planned dose in a quasi-clinical scenario. The alanine response was found to be linear in the dose in the clinical explored range (from 10 to 70 Gy). Furthermore, a depth dose profile in a quasi-clinical scenario was measured and compared to the dose computed by the Treatment Planning System PSIPLAN. The comparison of calibrated proton alanine measurements and TPS dose shows a difference under 1% in the SOBP and a "quenching" effect up to 4% in the distal part of SOBP. The positive dosimetric characteristics of the alanine pellets confirm the feasibility to use these detectors for "in vivo" dosimetry in clinical proton beams.

  14. pH-sensitive imaging by low-frequency EPR: a model study for biological applications

    International Nuclear Information System (INIS)

    The use of pH-sensitive nitroxides, in conjunction with low-frequency EPR, offers a unique opportunity for non-invasive assessment of pH values (in the range 0 to 14) in living animals. In the present study, we have investigated the potential use of pH-sensitive nitroxide free radicals in conjunction with EPR imaging techniques at low and very low frequencies (280 MHz - 2.1 GHz). In particular, we have measured the hyperfine splitting (hfs) of a pH-sensitive probe at three different EPR frequencies: 280 MHz, 1.1 GHz and 2.1 GHz. We have also developed EPR imaging experiments with phantoms simulating in vivo conditions, using pH-sensitive probes at 280 MHz (spatial-spatial) and 1.1 GHz (spectral-spatial). Finally, we discuss the actual sensitivity/resolution limits of the EPR imaging techniques at low frequencies. Practical applications of this method in the biomedical field are suggested for the continuous and non-invasive localization of pH in vivo. (author)

  15. A comparative EPR, infrared and Raman study of natural and deproteinated tooth enamel and dentin

    International Nuclear Information System (INIS)

    The aim of the present work was to investigate how the native signal observed in the electron paramagnetic resonance (EPR) spectrum of tooth enamel and dentin is associated with the organic content of the two tissues. This was achieved by comparing the EPR native signal and the optical bands (Raman and infrared, IR) associated with organic components of tooth enamel and dentin, in natural and deproteinated samples. The main results were: (a) in natural samples, the organic optical bands are more intense in dentin than in enamel, in contrast with the EPR native signal which shows similar intensity in the two tissues; (b) after deproteination, the optical organic bands are completely suppressed in both dentin and enamel, while the EPR native signal is eliminated only in dentin. It is suggested that the IR and Raman organic bands are originated in the bulk of the organic matrix, while the paramagnetic centres associated with the EPR native signal are located in the organic-mineral interface

  16. EPR in functional structures based on doped (nano, meso)-porous silica and titanium dioxide

    Science.gov (United States)

    Kassiba, A.; Makowska-Janusik, M.; Mehdi, A.

    2011-04-01

    EPR investigations are performed on mesoporous silica (SBA15) functionalized by Nickel-cyclam complexes (1,4,8,11-tetraazacyclotetradecane groups chelating nickel ions) and on mesoporous titanium dioxide with nitrogen doping. For functionalized silica, the magnetic behaviour of organometallic groups, their mutual interactions and dispersion in the host matrices are compared with respect to the doping rates and the synthesis procedures. The relaxation processes were analyzed from the thermal evolution of the paramagnetic spin susceptibilities and EPR line-widths. Particularly, some samples show the formation of clusters where phonon assisted one dimensional (1D) ferromagnetic ordering occurs below 45 K. For the mesoporous TiO2, systematic EPR investigations were performed on two main classes of materials with regard to the porosity degrees. The EPR experiments point out the efficiency of EPR method to probe the degree of functionalization of mesoporous silica or the nitrogen doping achievement in TiO2, and in general to give a valuable feedback to improve the synthesis routes of smart materials.

  17. EPR in functional structures based on doped (nano, meso)-porous silica and titanium dioxide

    International Nuclear Information System (INIS)

    EPR investigations are performed on mesoporous silica (SBA15) functionalized by Nickel-cyclam complexes (1,4,8,11-tetraazacyclotetradecane groups chelating nickel ions) and on mesoporous titanium dioxide with nitrogen doping. For functionalized silica, the magnetic behaviour of organometallic groups, their mutual interactions and dispersion in the host matrices are compared with respect to the doping rates and the synthesis procedures. The relaxation processes were analyzed from the thermal evolution of the paramagnetic spin susceptibilities and EPR line-widths. Particularly, some samples show the formation of clusters where phonon assisted one dimensional (1D) ferromagnetic ordering occurs below 45 K. For the mesoporous TiO2, systematic EPR investigations were performed on two main classes of materials with regard to the porosity degrees. The EPR experiments point out the efficiency of EPR method to probe the degree of functionalization of mesoporous silica or the nitrogen doping achievement in TiO2, and in general to give a valuable feedback to improve the synthesis routes of smart materials.

  18. EPR of F-type centres in pure LiBaF3 crystal

    International Nuclear Information System (INIS)

    Full text: We studied EPR spectra of pure LiBaF3 sample of high quality. For EPR measurements LiBaF3 sample was X-irradiated at room temperature, however spectra could be observed at low temperatures - at 77K. We could well resolve all hyperfine structure lines of F-type centre. Qualitative analysis with g-tensor parameters derived from magneto-optical measurements showed that the F-type centre observed earlier by MCD-EPR techniques [1, 2] is the same F-type centre we observe with the EPR. In this work we will analyse origin of the hyperfine structure of the EPR spectra and their angular dependencies and discuss the structure of F-type centres in the LiBaF3 crystal. [1] P.Kulis, I. Tale, M. Springis, U. Rogulis, J. Trokss, A. Veispals, H.-J. Fitting, Radiation Effects and Defects in Solids, 149 (1999) 97 - 100. [2] U.Rogulis, J.-M. Spaeth, I.Tale, M.Nikl, N.Ichinose, K.Shimamura, Radiation Measurements, 38 (2004) 663 - 666

  19. EPR spectrum deconvolution and dose assessment of fossil tooth enamel using maximum likelihood common factor analysis

    International Nuclear Information System (INIS)

    In order to determine the components which give rise to the EPR spectrum around g = 2 we have applied Maximum Likelihood Common Factor Analysis (MLCFA) on the EPR spectra of enamel sample 1126 which has previously been analysed by continuous wave and pulsed EPR as well as EPR microscopy. MLCFA yielded agreeing results on three sets of X-band spectra and the following components were identified: an orthorhombic component attributed to CO-2, an axial component CO3-3, as well as four isotropic components, three of which could be attributed to SO-2, a tumbling CO-2 and a central line of a dimethyl radical. The X-band results were confirmed by analysis of Q-band spectra where three additional isotropic lines were found, however, these three components could not be attributed to known radicals. The orthorhombic component was used to establish dose response curves for the assessment of the past radiation dose, DE. The results appear to be more reliable than those based on conventional peak-to-peak EPR intensity measurements or simple Gaussian deconvolution methods

  20. Site Directed Spin Labeling and EPR Spectroscopic Studies of Pentameric Ligand-Gated Ion Channels.

    Science.gov (United States)

    Basak, Sandip; Chatterjee, Soumili; Chakrapani, Sudha

    2016-01-01

    Ion channel gating is a stimulus-driven orchestration of protein motions that leads to transitions between closed, open, and desensitized states. Fundamental to these transitions is the intrinsic flexibility of the protein, which is critically modulated by membrane lipid-composition. To better understand the structural basis of channel function, it is necessary to study protein dynamics in a physiological membrane environment. Electron Paramagnetic Resonance (EPR) spectroscopy is an important tool to characterize conformational transitions between functional states. In comparison to NMR and X-ray crystallography, the information obtained from EPR is intrinsically of lower resolution. However, unlike in other techniques, in EPR there is no upper-limit to the molecular weight of the protein, the sample requirements are significantly lower, and more importantly the protein is not constrained by the crystal lattice forces. Therefore, EPR is uniquely suited for studying large protein complexes and proteins in reconstituted systems. In this article, we will discuss general protocols for site-directed spin labeling and membrane reconstitution using a prokaryotic proton-gated pentameric Ligand-Gated Ion Channel (pLGIC) from Gloeobacter violaceus (GLIC) as an example. A combination of steady-state Continuous Wave (CW) and Pulsed (Double Electron Electron Resonance-DEER) EPR approaches will be described that will enable a complete quantitative characterization of channel dynamics. PMID:27403967

  1. Optimization of bicelle lipid composition and temperature for EPR spectroscopy of aligned membranes

    Science.gov (United States)

    McCaffrey, Jesse E.; James, Zachary M.; Thomas, David D.

    2015-01-01

    We have optimized the magnetic alignment of phospholipid bilayered micelles (bicelles) for EPR spectroscopy, by varying lipid composition and temperature. Bicelles have been extensively used in NMR spectroscopy for several decades, in order to obtain aligned samples in a near-native membrane environment and take advantage of the intrinsic sensitivity of magnetic resonance to molecular orientation. Recently, bicelles have also seen increasing use in EPR, which offers superior sensitivity and orientational resolution. However, the low magnetic field strength (less than 1 T) of most conventional EPR spectrometers results in homogeneously oriented bicelles only at a temperature well above physiological. To optimize bicelle composition for magnetic alignment at reduced temperature, we prepared bicelles containing varying ratios of saturated (DMPC) and unsaturated (POPC) phospholipids, using EPR spectra of a spin-labeled fatty acid to assess alignment as a function of lipid composition and temperature. Spectral analysis showed that bicelles containing an equimolar mixture of DMPC and POPC homogeneously align at 298 K, 20 K lower than conventional DMPC-only bicelles. It is now possible to perform EPR studies of membrane protein structure and dynamics in well-aligned bicelles at physiological temperatures and below.

  2. Evaluation by EPR of potential antioxidant components of 60Co-irradiated varieties of soybean

    International Nuclear Information System (INIS)

    Brazil is today the second main producer of soybean in the world with a planted ground of about 21 million hectares and an annual production of 60 million tons in 2008, being slight more than a fourth of the annual production. The presence of flavonoids, particularly isoflavones in soybean products has been related as important for human health. It has been suggested that flavonoids play a role in the protection of plants by screening vital cellular components from damaging UV radiation. Electron paramagnetic resonance (EPR) spectroscopy can measure free radicals produced by dissociation molecules resulting from irradiation. It has been successfully employed for the detection of some irradiated food products. Twenty one Brazilian soybean cultivars from two crops were gamma-irradiated with a 60Co source and evaluated by EPR. Correlation coefficients were made among the central EPR signal (g = 2.0039) and the total and partial isoflavones contents. There was no correlation with total contents, though glicitein and acetyl-daidzin showed a negative correlation. Even 7 months after irradiation the intensity of central EPR signal were high enough to distinguish the irradiated samples. EPR measurements of separated parts of the grain were more efficient for that purpose, particularly from hilum and coat. The radiation did not change substantially the total isoflavone contents, although there were some evidences suggesting some conversion of glycosides to aglycones. (author)

  3. EPR spectrometer installed in a soft X-ray beamline at SPring-8 for biophysical studies

    Energy Technology Data Exchange (ETDEWEB)

    Yokoya, Akinari E-mail: yokoya@spring8.or.jp; Akamatsu, Ken

    2001-07-21

    We have developed an Electron paramagnetic resonance (EPR) system combined with a synchrotron beamline (Synchrotron Light Excited Electron Paramagnetic Resonance Spectrometer (SLEEPRS)) to detect radicals in biomolecules caused by irradiating with soft X-rays below 2 keV. SLEEPRS was installed in a soft X-ray undulator beamline equipped with a grazing incidence grating monochromator (BL23SU, SPring-8). The cavity of the X-band microwave was set in a high vacuum chamber connected with the beamline transport channel. The sample temperature was controlled from 10 to 300 K by a closed-cycle cryogenic system during the soft X-ray irradiation and the EPR measurements. Typical EPR signals of a deaminated alanine radical from L-{alpha}-alanine were observed by irradiating 1.5 keV soft X-rays. The calculated absorbed dose shows that a dose of the same order or less gives the same EPR signal intensity as that generated by a conventional 100 kVp X-ray source. Thus the combination of an EPR spectrometer and synchrotron soft X-ray beamline may open a way for investigating the radical processes involved in biomolecular damages induced by a selective K-photoabsorption of a specific atom.

  4. EPR spectrometer installed in a soft X-ray beamline at SPring-8 for biophysical studies

    International Nuclear Information System (INIS)

    We have developed an Electron paramagnetic resonance (EPR) system combined with a synchrotron beamline (Synchrotron Light Excited Electron Paramagnetic Resonance Spectrometer (SLEEPRS)) to detect radicals in biomolecules caused by irradiating with soft X-rays below 2 keV. SLEEPRS was installed in a soft X-ray undulator beamline equipped with a grazing incidence grating monochromator (BL23SU, SPring-8). The cavity of the X-band microwave was set in a high vacuum chamber connected with the beamline transport channel. The sample temperature was controlled from 10 to 300 K by a closed-cycle cryogenic system during the soft X-ray irradiation and the EPR measurements. Typical EPR signals of a deaminated alanine radical from L-α-alanine were observed by irradiating 1.5 keV soft X-rays. The calculated absorbed dose shows that a dose of the same order or less gives the same EPR signal intensity as that generated by a conventional 100 kVp X-ray source. Thus the combination of an EPR spectrometer and synchrotron soft X-ray beamline may open a way for investigating the radical processes involved in biomolecular damages induced by a selective K-photoabsorption of a specific atom

  5. New developed cylindrical TM010 mode EPR cavity for X-band in vivo tooth dosimetry.

    Directory of Open Access Journals (Sweden)

    Guo Junwang

    Full Text Available EPR tooth in vivo dosimetry is an attractive approach for initial triage after unexpected nuclear events. An X-band cylindrical TM010 mode resonant cavity was developed for in vivo tooth dosimetry and used in EPR applications for the first time. The cavity had a trapezoidal measuring aperture at the exact position of the cavity's cylindrical wall where strong microwave magnetic field H1 concentrated and weak microwave electric field E1 distributed. Theoretical calculations and simulations were used to design and optimize the cavity parameters. The cavity features were evaluated by measuring DPPH sample, intact incisor samples embed in a gum model and the rhesus monkey teeth. The results showed that the cavity worked at designed frequency and had the ability to make EPR spectroscopy in relative high sensitivity. Sufficient modulation amplitude and microwave power could be applied into the aperture. Radiation induced EPR signal could be observed remarkably from 1 Gy irradiated intact incisor within only 30 seconds, which was among the best in scan time and detection limit. The in vivo spectroscopy was also realized by acquiring the radiation induced EPR signal from teeth of rhesus monkey whose teeth was irradiated by dose of 2 Gy. The results suggested that the cavity was sensitive to meet the demand to assess doses of significant level in short time. This cavity provided a very potential option for the development of X-band in vivo dosimetry.

  6. New developed cylindrical TM010 mode EPR cavity for X-band in vivo tooth dosimetry.

    Science.gov (United States)

    Junwang, Guo; Qingquan, Yuan; Jianbo, Cong; Lei, Ma; Guofu, Dong; Guoshan, Yang; Ke, Wu

    2014-01-01

    EPR tooth in vivo dosimetry is an attractive approach for initial triage after unexpected nuclear events. An X-band cylindrical TM010 mode resonant cavity was developed for in vivo tooth dosimetry and used in EPR applications for the first time. The cavity had a trapezoidal measuring aperture at the exact position of the cavity's cylindrical wall where strong microwave magnetic field H1 concentrated and weak microwave electric field E1 distributed. Theoretical calculations and simulations were used to design and optimize the cavity parameters. The cavity features were evaluated by measuring DPPH sample, intact incisor samples embed in a gum model and the rhesus monkey teeth. The results showed that the cavity worked at designed frequency and had the ability to make EPR spectroscopy in relative high sensitivity. Sufficient modulation amplitude and microwave power could be applied into the aperture. Radiation induced EPR signal could be observed remarkably from 1 Gy irradiated intact incisor within only 30 seconds, which was among the best in scan time and detection limit. The in vivo spectroscopy was also realized by acquiring the radiation induced EPR signal from teeth of rhesus monkey whose teeth was irradiated by dose of 2 Gy. The results suggested that the cavity was sensitive to meet the demand to assess doses of significant level in short time. This cavity provided a very potential option for the development of X-band in vivo dosimetry. PMID:25222483

  7. EPR and OSL emergency dosimetry with teeth: A direct comparison of two techniques

    International Nuclear Information System (INIS)

    The OSL dosimetry technique with teeth has been validated against the EPR dosimetry technique through a measurement comparison performed on the same teeth. The OSL reconstructed doses were found to be in agreement with corresponding EPR doses. Minimum measurable doses for the OSL technique were estimated to be in the range 0.9–1.5 Gy for measurements made within 24 h post-exposure if OSL signals are collected from 6 teeth at the same time. These values satisfy the requirements for emergency triage dosimetry. The fading of tooth OSL signals correlated with fading of radiation-induced EPR signals observed at g = 2.0115 that are attributed to CO3- radicals. OSL sensitivity can be enhanced if more teeth from the same individual will be used for the signal accumulation. - Highlights: • OSL and EPR dose reconstruction techniques were compared on the same teeth. • Values of minimum measurable doses for the OSL technique were in the range 0.9–1.5 Gy. • Fading of OSL signals correlated with fading of EPR signals attributed to CO3- radicals

  8. International intercomparison of dose measurements using EPR spectrometry of tooth enamel

    International Nuclear Information System (INIS)

    Electron paramagnetic resonance (EPR) dosimetry with teeth is the only solid state dosimetry method that allows for direct measurement of the individual dose. It is considered to be a very promising tool for retrospective individual dosimetry after accidental radioactive releases. It will help to make a reliable assessment of the radiation risk. A number of laboratories are engaged in retrospective EPR dosimetry with teeth. There is consequently a need to develop a programme of intercalibration and intercomparison to check whether the results produced by different laboratories are either consistent or accurate. The Commission of the European Communities has initiated the project ECP10 entitled, Retrospective Dosimetry and Dose reconstruction. Within the joint Eu/CIS project the 1st International Intercomparison of EPR Dosimetry with Teeth' was started in 1994. Nine research laboratories were involved from Germany, Russia, Belarus, Ukraine, Estonia and USA

  9. Towards improving the detection limit of electron paramagnetic resonance (EPR) dosimetry of drywall (wallboard)

    International Nuclear Information System (INIS)

    The intensity of the electron paramagnetic resonance (EPR) line corresponding to the carbonate free radical (CO3-) in gypsum (CaSO4·2H2O) drywall was previously shown to be proportional to absorbed dose. Heating irradiated drywall reduces the radiosensitive signal of the CO3- radical. The response of the CO3- EPR line to heat treatments is being studied in order to determine a background for an arbitrary drywall sample. Ultimately this is expected to improve the precision of dose measurements with drywall and to reduce the detection limit. Controlled heating of irradiated drywall was performed at temperatures between 50oC and 100oC. Although higher temperatures reduce the radiosensitive signal rapidly, the non-radiosensitive EPR signals are affected dramatically as well, presumably due to a phrase change from gypsum to plaster of Paris to anhydrite. (author)

  10. On Room-Temperature Inversion of EPR Signals of P1 Centre in Synthetic Diamond

    Institute of Scientific and Technical Information of China (English)

    G. G. Fedoruk; O. N. Poklonskaya

    2009-01-01

    Room-temperature inversion of EPR absorption signals of P1 centre in synthetic diamond is studied by the tran-sient nutation technique. Use of the bichromatic field, consisting of a transverse microwave field and longitudinal radio frequency field, allows to investigate the dynamics of P1 centres in the same field configuration as in cw EPR spectrometers. It is shown that the annealing decreases the P1 centre concentration and, respectively, increases the spin-spin relaxation time. As a result, the periodic inversion (nutation) of the P1 centre absorption signal is observed longer. It is assumed that the P1 centre signal inversion, which was previously observed by cw EPR, might be caused by the Bloch-Siegert effect in the biehromatic field.

  11. Radiation-induced signals analysed by EPR spectrometry applied to fortuitous dosimetry

    International Nuclear Information System (INIS)

    Dosimetry based on the detection by electron paramagnetic resonance (EPR) spectroscopy of ionizing radiation-induced radicals is an established method for the retrospective dosimetry of past exposures and the dosimetry of potentially exposed persons in radiological emergencies. The dose is estimated by measuring the physical damage induced in materials contained in objects placed on or next to the potentially exposed person. The aim of this paper is to survey the current literature about methodologies and materials that have been proposed for EPR dosimetry, in order to identify those that could be suitable for population triage according to criteria such as ubiquity, non invasiveness and easy sample collection, presence of a post-irradiation EPR signal, negligible background signal, linearity of dose-response relationship, minimum detection limit and post-irradiation signal stability. The paper will survey the features of sugar, plastics, glass, clothing tissues, and solid biological tissues (nails, hair and calcified tissues).

  12. Saccharides as Prospective Immobilizers of Nucleic Acids for Room-Temperature Structural EPR Studies.

    Science.gov (United States)

    Kuzhelev, Andrey A; Shevelev, Georgiy Yu; Krumkacheva, Olesya A; Tormyshev, Victor M; Pyshnyi, Dmitrii V; Fedin, Matvey V; Bagryanskaya, Elena G

    2016-07-01

    Pulsed dipolar electron paramagnetic resonance (EPR) spectroscopy is a powerful tool for structural studies of biomolecules and their complexes. This method, whose applicability has been recently extended to room temperatures, requires immobilization of the studied biosystem to prevent averaging of dipolar couplings; at the same time, the modification of native conformations by immobilization must be avoided. In this work, we provide first demonstration of room-temperature EPR distance measurements in nucleic acids using saccharides trehalose, sucrose, and glucose as immobilizing media. We propose an approach that keeps structural conformation and unity of immobilized double-stranded DNA. Remarkably, room-temperature electron spin dephasing time of triarylmethyl-labeled DNA in trehalose is noticeably longer compared to previously used immobilizers, thus providing a broader range of available distances. Therefore, saccharides, and especially trehalose, can be efficiently used as immobilizers of nucleic acids, mimicking native conditions and allowing wide range of structural EPR studies at room temperatures. PMID:27320083

  13. On Room-Temperature Inversion of EPR Signals of P1 Centre in Synthetic Diamond

    International Nuclear Information System (INIS)

    Room-temperature inversion of EPR absorption signals of P1 centre in synthetic diamond is studied by the transient nutation technique. Use of the bichromatic field, consisting of a transverse microwave field and longitudinal radio frequency field, allows to investigate the dynamics of P1 centres in the same field configuration as in cw EPR spectrometers. It is shown that the annealing decreases the P1 centre concentration and, respectively, increases the spin-spin relaxation time. As a result, the periodic inversion (nutation) of the P1 centre absorption signal is observed longer. It is assumed that the P1 centre signal inversion, which was previously observed by cw EPR, might be caused by the Bloch–Siegert effect in the bichromatic field

  14. In vivo EPR: an effective new tool for studying pathophysiology, physiology and pharmacology

    International Nuclear Information System (INIS)

    The development of spectrometers working at lower frequencies with improved resonators now permits the routine use of non-invasive EPR spectroscopy in vivo. The capabilities of EPR spectra to reflect environmental conditions, combined with the use of paramagnetic materials as selective non-toxic labels, has led to increasingly widespread and productive applications of the technique to complex problems involving physiology, pharmacology and pathophysiology. Some of the especially promising applications in which EPR techniques uniquely appear to provide valuable information are illustrated, including the measurement of oxygen and oxygen gradients, monitoring of the metabolism of xenobiotics, monitoring pharmacokinetics of drugs, measurement of perfusion, measurement of pH, recognition and labeling of receptors, and characterization of drug releasing systems. (author)

  15. Some elements of understanding about the cluster ejection accident in the EPR

    International Nuclear Information System (INIS)

    The author answers to a publication made by an association (Sortir du Nucleaire) which is provided in appendix (some parts of this text are highlighted) and denounced risks associated with a cluster ejection accident in an EPR in relationship with steering modes which, according to this association, would be essentially related to an objective of economic profitability. The author first recalls some elements regarding the control and neutron stopping of pressurized water reactors. Then, after having outlined some specific aspects of the EPR design, he addresses the cluster ejection accident: safety approach and its application to this type of accident. He recalls the conclusions of studies of cluster ejection performed by EDF and AREVA, comments the consequences for the EPR power

  16. Photonic EPR State from Quadratic Waveguide Array with Alternating Positive and Negative Couplings

    Science.gov (United States)

    Ying, Yang; Ping, Xu; Liang-Liang, Lu; Shi-Ning, Zhu

    2016-02-01

    We propose the generation of photonic EPR state from quadratic waveguide array. Both the propagation constant and the nonlinearity in the array are designed to possess a periodical modulation along the propagation direction. This ensures that the photon pairs can be generated efficiently through the quasi-phase-matching spontaneous parametric down conversion by holding the spatial EPR entanglement in the fashion of correlated position and anticorrelated momentum. The Schmidt number which denotes the degree of EPR entanglement is calculated and it can approach a high value when the number of illuminated waveguide channels and the length of the waveguide array are properly chosen. These results suggest the quadratic waveguide array as a compact platform for engineering photonic quantum states in a high-dimensional Hilbert space. Supported by the State Key Program for Basic Research in China under Grant No. 2012CB921802, the National Natural Science Foundations of China under Grant Nos. 91321312, 11321063 and 11422438

  17. Copper ESEEM and HYSCORE through ultra-wideband chirp EPR spectroscopy.

    Science.gov (United States)

    Segawa, Takuya F; Doll, Andrin; Pribitzer, Stephan; Jeschke, Gunnar

    2015-07-28

    The main limitation of pulse electron paramagnetic resonance (EPR) spectroscopy is its narrow excitation bandwidth. Ultra-wideband (UWB) excitation with frequency-swept chirp pulses over several hundreds of megahertz overcomes this drawback. This allows to excite electron spin echo envelope modulation (ESEEM) from paramagnetic copper centers in crystals, whereas up to now, only ESEEM of ligand nuclei like protons or nitrogens at lower frequencies could be detected. ESEEM spectra are recorded as two-dimensional correlation experiments, since the full digitization of the electron spin echo provides an additional Fourier transform EPR dimension. Thus, UWB hyperfine-sublevel correlation experiments generate a novel three-dimensional EPR-correlated nuclear modulation spectrum. PMID:26233121

  18. EPR Studies on Octakis (1-Naphthyl-Methylthio) Substituted Porphyrazine Derivatives

    International Nuclear Information System (INIS)

    New porphyrazines surrounded with eight bulky and electron-rich naphthyl groups have been described, high electron density on the substituents results with a second absorption in the ultraviolet region of comparable intensity as the intense B band of porphyrazines. Characterization of octakis (1-naphthyl-methylthio) substituted porphyrazine derivatives coordinated by Co2+ and Cu2+ have been supported by EPR study. Spin-Hamiltonian parameters and line width characteristics have been obtained for both solid powder and solution forms of ion coordinated complexes. Theoretical simulations were drawn for each registered EPR spectra. Stable planar structure has been proven for both Co2+ and Cu2+ coordinated complexes one more time. Orbital energy levels for magnetic electrons were determined from EPR parameters.

  19. Detection and identification of nitrogen defects in nanodiamond as studied by EPR

    International Nuclear Information System (INIS)

    Electron paramagnetic resonance (EPR) and electron spin echo (ESE) at X-band and at high-frequency W-band (95 GHz) have been used to study defects in natural diamond nanocrystals, detonation nanodiamond (ND) with a size of ∼4.5 nm and detonation ND after high-temperature, high-pressure sintering with a size of ∼8.5 nm. Atomic nitrogen centers N0 and nitrogen pairs N2+ have been detected and identified and their structure has been unambiguously determined by means of the high frequency EPR and ESE in natural diamond nanocrystals. In detonation ND and detonation ND after sintering atomic nitrogen centers N0 have been discovered in nanodiamond core. In addition EPR signal of multi-vacancy centers with spin 3/2 seems to be observed in diamond core of detonation ND.

  20. EPR dosimetry for actual and suspected overexposures during radiotherapy treatments in Poland

    International Nuclear Information System (INIS)

    EPR dosimetry on bone samples was recently used for actual and suspected overexposures during radiotherapy treatments performed in Poland. In 2001 five breast-cancer patients undergoing radiotherapy in the Bialystok Oncology Center, Poland, were overexposed. The overexposure was due to a defective safety interlock and an obsolete safety system of the linear accelerator. For the three most exposed patients, pieces of rib bones removed during surgical reconstruction of the chest wall and skin transplantation allowed an estimation of the accident doses by electron paramagnetic resonance (EPR) spectrometry. The doses delivered during the accident were as high as 60-80 Gy. In 2005, a patient treated in Kielce Holy Cross Cancer Center exhibited similar deep necroses of the chest wall but 6 years following a 'standard upper mantel fields' radiotherapy for Hodgkin's disease. In order to investigate the possible late effect of an overexposure as necrosis origin, the delivered dose was afterward estimated by EPR dosimetry performed on a rib sample

  1. A reinvestigation of EXAFS and EPR spectroscopic measurements of chromium(VI) reduction by coir pith

    International Nuclear Information System (INIS)

    New measurements using extended X-ray absorption fine structure (EXAFS) and electron paramagnetic resonance (EPR) techniques are consistent with Cr in the Cr(III) oxidation state as the main product from the adsorption of Cr(VI) on coir pith. These confirm the previous X-ray measurements, but differ from the results of previous EPR studies, which indicated that Cr(V) was the main form of Cr. The reason for this discrepancy is the presence of a broad signal from Cr(III) in an unsymmetrical environment that was missed previously; the Cr(V) component is in fact only a minor reaction product. As a result of this problem with spectral acquisition and interpretation, some simple recommendations are presented for conducting EPR investigations on natural systems.

  2. Characterization by XRD and electron paramagnetic resonance (EPR) of waste materials from 'Cerro Matoso' Mine (Colombia)

    International Nuclear Information System (INIS)

    Materials from a mining process, in which ferronickel metal extraction is the principal aim, were studied. The residual solid (scum) obtained in this process leads to large-scale accumulation of a vitreous material (pollutant) which creates an environmental problem. These materials were characterized by EPR, X-ray diffraction and X-ray fluorescence. The results indicate that the analyzed solids are rich in Fe2O3 and NiO among other oxides. The scum material shows diffraction signals corresponding to the minerals enstatite (pyroxene) and α-alumina. Moreover, the scum EPR analysis showed a broad line around g = 2.1 corresponding to Fe3+ clusters in a complex glassy matrix. An analysis of EPR at different temperatures was also performed. The objective of this work, as a first exploratory stage, is to develop a better understanding of the residual solids in order to identify potential applications

  3. Interlaboratory trials of the EPR method for the detection of irradiated spices, nutshell and eggshell

    International Nuclear Information System (INIS)

    The Electron Paramagnetic Resonance (EPR) spectrometry detection method for irradiated foods is based on the measurement of free radicals produced in the rigid matrices of foods (e.g. bones, shell, seeds). For certain foods, these free radicals are stable over part of all of the shelf-life of the food. As part of the International Atomic Energy Agency coordinated research programme ADMIT (Analytical Detection Methods for Irradiation Treatment of Foods), two trials of an EPR method for spices and nutshell were undertaken. In the second of these trials eggshell was included for testing. This work describes the two ADMIT trials and identifies some essential elements of a protocol for implementation of the EPR method. (author)

  4. Orientation of crystals in alanine dosimeter assessed by DRS, as seen in EPR spectra evaluation

    International Nuclear Information System (INIS)

    The alanine dosimeter made for evaluation by diffuse light reflection spectrophotometry (ALA/DRS) does not show the effect of orientation of crystals. Supposed deviation from random orientation has been investigated by EPR spectroscopy. EPR investigation shows that in spite of the very fine size of L-alanine crystals, they are oriented in thin layers of the polyethylene matrix. Specially prepared films with deliberately well oriented crystals have confirmed this observation. Our ALA/DRS dosimeter can be evaluated by the EPR method for the concentration of free radicals, providing that the dominating crystal orientation in the dosimetric film is indicated on it as an arrow, and the sample is inserted into the magnetic cavity always in the same orientation as has been done during the calibration operation. (author). 6 refs., 2 figs

  5. BCL::MP-Fold: membrane protein structure prediction guided by EPR restraints

    CERN Document Server

    Fischer, Axel Walter; Woetzel, Nils; Karakas, Mert; Weiner, Brian; Meiler, Jens

    2015-01-01

    For many membrane proteins the determination of their topology remains a challenge for methods like X-ray crystallography and nuclear magnetic resonance (NMR) spectroscopy. Electron paramagnetic resonance (EPR) spectroscopy has evolved as an alternative technique to study structure and dynamics of membrane proteins. The present study demonstrates the feasibility of membrane protein topology determination using limited EPR distance and accessibility measurements. The BCL::MP-Fold (BioChemical Library membrane protein fold) algorithm assembles secondary structure elements (SSEs) in the membrane using a Monte Carlo Metropolis (MCM) approach. Sampled models are evaluated using knowledge-based potential functions and agreement with the EPR data and a knowledge-based energy function. Twenty-nine membrane proteins of up to 696 residues are used to test the algorithm. The RMSD100 value of the most accurate model is better than 8{\\AA} for twenty-seven, better than 6{\\AA} for twenty-two and better than 4{\\AA} for fifte...

  6. Finnish EPR Olkiluoto 3. The world's first third-generation reactor now under construction

    International Nuclear Information System (INIS)

    The EPR was developed by Framatome and Siemens KWU (the nuclear division of Siemens), whose nuclear activities were combined in January 2001 to form Framatome ANP, now AREVA NP. The French electricity utility EDF (Electricite de France), together with the major German utilities, played an active role in the project. The safety authorities of the two countries joined forces to bring their respective safety standards into line and draw up joint design rules for the new reactor. On December 18, 2003, the consortium formed by AREVA and Siemens - and led by AREVA - signed a contract with TVO for the turnkey construction of the EPR. The overall Olkiluoto 3 project cost has been estimated by TVO at around euros 3 Billion. TVO is responsible for the overall project management and licensing process with the Finnish Safety Authority STUK. In the pre-qualification phase, STUK concluded that the EPR can meet the Finnish licensing requirements. All specific comments will be taken into account for the realization of the project. In January 2005, STUK emphasized in its safety assessment that the evolutionary EPR design compared to predecessor product lines has been further enhanced by AREVA. This paper presents first, The Finnish energy situation (Electricity consumption and supply, Finland's Kyoto CO2 cutback, Competitiveness of nuclear power), and then the EPR in Olkiluoto (General schedule of responsibilities, Important milestones of the project). Finally, the EPR third-generation and advanced reactor is presented with its position in the international competition (Targeted design objectives, Main characteristics, competitiveness, safety, Additional measures to prevent the occurrence of events likely to damage the core, Increased protection against the consequences of core melt)

  7. Nanosecond time-resolved EPR in pulse radiolysis via the spin echo method

    International Nuclear Information System (INIS)

    The design and operation of a time-resolved electron spin echo spectrometer suitable for detecting transient radicals produced by 3 MeV electron radiolysis is described. Two modes of operation are available: Field swept mode which generates a normal EPR spectrum and kinetic mode in which the time dependence of a single EPR line is monitored. Techniques which may be used to minimize the effects of nonideal microwave pulses and overlapping sample tube signals are described. The principal advantages of the spin echo method over other time-resolved EPR methods are: (1) Improved time resolution (presently approx.30--50 nsec) allows monitoring of fast changes in EPR signals of transient radicals, (2) Lower susceptibility to interference between the EPR signal and the electron beam pulse at short times, and (3) Lack of dependence of transient signals on microwave field amplitude or static field inhomogeneity at short times. The performance of the instrument is illustrated using CIDEP from acetate radical formed in pulsed radiolysis of aqueous solutions of potassium acetate. The relaxation time and CIDEP enhancement factor obtained for this radical using the spin echo method compare favorably with previous determinations using direct detection EPR. Radical decay rates yield estimates of initial radical concentrations of 10-410-3M per electron pulse. The Bloch equations are solved to give an expression for the echo signal for samples exhibiting CIDEP using arbitrary microwave pulse widths and distributions of Larmor frequencies. Conditions are discussed under which the time-dependent signal would be distorted by deviations from an ideal nonselective 900--tau--1800 pulse sequence

  8. EPR invastigation of glasses on the base of the oxides of vanadium and tellurium

    International Nuclear Information System (INIS)

    The results of investigation of EPR spectra of the nV2O5(100-n)TeO2 binary system in the range from 95 to 5 mol % V2O5 with the 5 mol % step on the DRON-2 installation (X-ray diffraction measurements) are presented. The EPR spectra were read out on the RE-1301 spectrometer at liquid nitrogen and room temperatures. The concentration of the EPR centres was determined by comparing it with the signal from the known number of Cu2+ ions in the CuSO4x5H2O crystal. It is established that the VO2+ complexes were the EPR centres. In all prepared samples the EPR spectra were observed, and at n=70 the SFS components were revealed both in the crystalline (with the TeO2 content up to 30 mol %) and in amorphous states. The singularities of the EPR spectrum are discussed on the basis of the spin-hamiltonian with axial asymmetry. The dependence of the spin-hamiltonian components on the content was revealed and the P=670 value characterizing the average value of the distance between the nucleus and noncoupled electron is found. Observation of the line with well resoluted SFS components in the amorphous samples is explained by 'a great freedom'' of paramagnetic ions in the choice of close environment, and consequently the field of ligand atoms localizing in the paramagnetic ion produces the ''strong field'' effect (D, E>>GβH, G=1.985+-0.005) and removes degeneration due to the presence of the I=7/2 nuclear momentum of the V4+ ion. Conservation of the SFS lines even at room temperature is connected with great scattering of the spin-lattice relaxation time

  9. Electron paramagnetic resonance (EPR) in characterization of rocks and minerals

    Energy Technology Data Exchange (ETDEWEB)

    Valezi, D.F.; Mauro, E. di [Universidade Estadual de Londrina (UEL), PR (Brazil). Centro de Ciencias Exatas. Lab. de Fluorescencia e Ressonaancia Paramagnetica Eletronica (LAFLURPE); Zaia, D.A.M.; Carneiro, C.E.A. [Universidade Estadual de Londrina (UEL), PR (Brazil). Centro de Ciencias Exatas. Dept. de Quimica; Costa, A.C.S. da [Universidade Estadual de Maringa (UEM), PR (Brazil). Centro de Ciencias Agrarias. Dept. de Agronomia

    2011-07-01

    Full text. his work is based on the study of several stones and minerals from the Parana state, Brazil. They were analyzed by the Electron Paramagnetic Resonance (EPR) technique. The measurements were made on a spectrometer JEOL (JES-PE-3X), operating on X-band and at room temperature, with the exception of the mineral Goethite, which was measured with temperature variation. In all the samples were determined spectroscopic factors (or g factor) and line widths of paramagnetic species. A great number of the samples showed in their spectra, the presence of iron complexes. Phyllite and shale showed a resonance signal with approximately g = 2, and line width with about 1000 Gauss, which indicates the presence of the hematite mineral hematite in these rocks. Shale and coal samples showed the presence of free radical, it was identified as a very intense signal, centered at about g = 2.003. Phyllite sample showed in its spectra a resonance signal between the third and fourth line of the g marker (Mg O:Mn{sup 2+}) used in the measurements, and also a signal at g = 4.3, these characteristics may indicate the presence of Kaolinite in the sample. Limestone showed a signal with line width of about 600 Gauss, centered around g = 2, this signal is probably due to a mixture of ferrihydrite and some other compound, besides the presence of manganese, displaying a spectra with its six peculiar lines, due to hyperfine splitting. The two different types of limestone presented a overlap of two distinct spectra lines for the manganese, in the first limestone sample, rich in calcite, the existence of these different spectra is a result of the manganese substitution in a single site with different orientations of the calcite; the other limestone sample, this one abundant in dolomite, the existence of these different spectra is the result of the manganese substitution in different dolomite sites, taking the place of calcium and or of the magnesium. Now, we are focusing our research in the

  10. EPR study of the free radicals in the spices and pigments turmeric and saffron

    International Nuclear Information System (INIS)

    Full text: The spices Turmeric (curcuma longa) and Saffron (crocus sativus) have also been used as pigments. The EPR spectrum of each shows a readily detectable free radical signal. EPR spectra of the available pure chief active colorants in solid form also give free radical signals. Curcumin (turmeric) is a 'linear' symmetric phenolic, so is expected to do so. The peptide turmerin (commercially unavailable), containing sulphur, may also contribute to the ESR signal. Crocetin (saffron) is a 'linear' molecule, related to the beta-carotenes, which do not give free radical signals: but it does, presumably because of its particular resonant structure properties

  11. EPR dosimetry of teeth in past and future accidents: a prospective look at a retrospective method

    International Nuclear Information System (INIS)

    Electron paramagnetic resonance spectroscopy (EPR) of tooth enamel is a relatively new technique for retrospective dosimetry that in the past two years has seen increasing effort towards its development and evaluation. Efforts have centered on determining the accuracy which may be achieved with current measurement techniques as well as the minimum doses detectable. The study was focused on evaluating some factors which influence the accuracy of EPR dosimetry of enamel. Reported are studies on sample intercomparisions, instrumental considerations, and effects of dental x-rays, environmental sunlight and ultraviolet radiation

  12. Correlated four-component EPR g-tensors for doublet molecules

    DEFF Research Database (Denmark)

    Vad, M.S.; Pedersen, M.N.; Nørager, A.;

    2013-01-01

    The first correlated ab initio four-component calculations of electron paramagnetic resonance (EPR) g-tensors for doublet radicals are reported. We have implemented a first-order degenerate perturbation theory approach based on the four-component Dirac-Coulomb Hamiltonian and fully relativistic...... configuration interaction wave functions in the DIRAC program package. We find that the correlation effects on the g-tensors can be sufficiently well described with manageable basis sets of triple-zeta quality and manageable configuration spaces. The new fully relativistic EPR module in DIRAC should be useful...

  13. Use of polyphase continuous excitation based on the Frank sequence in EPR.

    Science.gov (United States)

    Tseitlin, Mark; Quine, Richard W; Eaton, Sandra S; Eaton, Gareth R

    2011-08-01

    Polyphase continuous excitation based on the Frank sequence is suggested as an alternative to single pulse excitation in EPR. The method allows reduction of the source power, while preserving the excitation bandwidth of a single pulse. For practical EPR implementation the use of a cross-loop resonator is essential to provide isolation between the spin system and the resonator responses to the excitation. Provided that a line broadening of about 5% is acceptable, the cumulative turning angle of the magnetization vector generated by the excitation sequence can be quite large and can produce signal amplitudes that are comparable to that achieved with a higher power 90° pulse. PMID:21737326

  14. EPR, mass, IR, electronic, and magnetic studies on copper(II) complexes of semicarbazones and thiosemicarbazones

    Science.gov (United States)

    Chandra, Sulekh; Gupta, Lokesh Kumar

    2005-01-01

    Copper(II) complexes having the general composition Cu(L) 2X 2 [where L = isopropyl methyl ketone semicarbazone (LLA), isopropyl methyl ketone thiosemicarbazone (LLB), 4-aminoacetophenone semicarbazone (LLC), and 4-aminoacetophenone thiosemicarbazone (LLD) and X = Cl -, 1/2SO 42-] have been synthesized. All the Cu(II) complexes reported here have been characterized by elemental analyses, molar conductance, magnetic moment susceptibility, EI mass, 1H NMR, IR, EPR, and electronic spectral studies. All the complexes were found to have magnetic moments corresponding to one unpaired electrons. The possible geometries of the complexes were assigned on the basis of EPR, electronic, and infrared spectral studies.

  15. EPR of molybdenum-related defect in CdWO4 crystal

    International Nuclear Information System (INIS)

    EPR spectra of a molybdenum-related structure defect have been observed at a temperature of 20 K in CdWO4 scintillator crystal, being as-grown 'blue-coloured'. Mo95 and Mo97 isotope superhyperfine (shf) splittings have been resolved. Further splittings in EPR spectra have been interpreted as arising from shf interactions with W nuclea. In the present model of the defect, the unpaired spin is localised in the Cd-site position and molybdenum replaces one of the neighbouring W atoms

  16. The first international intercomparison of EPR-dosimetry with teeth: first results

    International Nuclear Information System (INIS)

    Intercomparison of EPR-dosimetric techniques using tooth enamel has been performed in order to check whether the results produced by different laboratories are consistent and accurate. Participants were supposed to evaluate doses applied to pulverized enamel samples, using routine techniques from their laboratories. The intercomparison has demonstrated a great variety of methods used for dose reconstruction. Peculiarities of experimental approaches are discussed systematically in terms of procedure for recording the EPR-spectra, determination of the amplitude of the radiation induced signal, determination of the dose, and error propagation. (Author)

  17. Manufacturing of nozzle shell with integral flange for EPR reactor pressure vessel and its properties

    International Nuclear Information System (INIS)

    EPR (EPR: European Pressurized Water Reactor) has been developed to achieve higher output (1,600 MW) and longer plant life (60 years), compared with the conventional unclear reactors, and the first commercial reactor was introduced in Finland no.5/Olkiluoto no.3. The integrated mono-block design was applied for nozzle shell flange instead of welded conventional flange and nozzle shell. And due to set-on type nozzles, a 600 ton ingot was required for this part. JSW successfully completed the manufacturing of first nozzle shell with integral flange 11 months after melting. This report summarizes manufacturing technology and process, and properties of nozzle shell with integral flange. (author)

  18. Characterization of lithium formate EPR dosimeters for high dose applications - Comparison with alanine

    International Nuclear Information System (INIS)

    Lithium formate and L-α-alanine (alanine) EPR dosimeters were irradiated to doses from 100 Gy to 100 kGy. The irradiations were mainly performed at a Gammacell irradiator with dose rate of approximately 5.5 kGy h-1. Both the peak-to-peak amplitude of the first derivative EPR spectrum and the area under the EPR absorption spectrum were extracted, and the resulting dose dependence of these EPR signal intensity parameters was analyzed. The dependence of the peak-to-peak width of the central resonance in the first derivative EPR spectrum on the dose was also elucidated. In addition, the dependence on dose rate and irradiation temperature for the two materials were measured. Dosimeters were given doses from 100 Gy to 10 kGy at two different Gammacells with dose rates of 5.5 kGy h-1 and 0.6 kGy h-1, respectively, and the results were compared. Furthermore, the EPR signal intensities for dosimeters irradiated to 1 kGy at temperatures from 11 oC to 40 oC were analyzed. By fitting an 'exponential rise to maximum'-function to the dependence of the area under the EPR absorption spectrum on the dose, saturation doses of 53 kGy and 87 kGy for lithium formate and alanine, respectively, were found. Lower estimates were found when analyzing the dose dependence of the peak-to-peak amplitude. Furthermore, the peak-to-peak width was found to increase for doses above 10 kGy. No dose rate dependence for any of the studied materials was observed and the temperature coefficients at 25 oC (i.e. change in dosimeter signal per oC change in irradiation temperature) were 0.154% K-1 and 0.161% K-1 for lithium formate and alanine, respectively. This work demonstrates that lithium formate EPR dosimeters may be suitable for high dose applications, but their signals saturate at lower doses than alanine. The saturation doses found for both materials may be used in theoretical calculations of the dosimeter response following hadron beam irradiations.

  19. Improving noise threshold for optical quantum computing with the EPR photon source

    CERN Document Server

    Wei, Z -H; OH, C H; Duan, L -M

    2009-01-01

    We show that the noise threshold for optical quantum computing can be significantly improved by using the EPR-type of photon source. In this implementation, the detector efficiency $\\eta_{d}$ is required to be larger than 50%, and the source efficiency $\\eta_{s}$ can be an arbitrarily small positive number. This threshold compares favorably with the implementation using the single-photon source, where one requires the combined efficiency $\\eta_{d}\\eta_{s}>2/3$. We discuss several physical setups for realization of the required EPR photon source, including the photon emitter from a single-atom cavity.

  20. Synthesis, EPR, Electronic and Magnetic Studies on Cobalt (II) Complexes of Semicarbazone and Thiosemicarbazone

    International Nuclear Information System (INIS)

    Cobalt (II) complexes having the general composition Co(L2) X2 [where Lisopropyl methyl ketone semicarbazone (LLA), isopropyl methyl ketone thiosemicarbazone (LLB), 4-aminoacetophenone semicarbazone (LLC) and4-aminoacetophenone thiosemicarbazone (LLD) and X=Cl] have been synthesized. All the Co(II) complexes reported here have been characterized by elemental analyses, magnetic moments, IR, electronic and EPR spectral studies. All the complexes were found to have magnetic moments corresponding to three unpaired electrons. The possible geometries of the complexes were assigned on the basis of electronic infrared and EPR spectral studies. (author) = = = = = = = = = = = = = = =

  1. Estimation of radiation levels by EPR measurement of tooth enamel in Indian populations

    Energy Technology Data Exchange (ETDEWEB)

    El-Faramawy, N.A. [GSF-National Research Center for Environment and Health, Institute for Radiation Protection, D-85758 Neuherberg (Germany) and Department of Physics, Faculty of Science, Ain Shams University, Cairo (Egypt)]. E-mail: na_bil@yahoo.com

    2005-02-01

    Enamel from 34 molars from 22 individuals in the general population are used to evaluate the background radiation in six cities in India. The estimation of the background dose for each tooth is evaluated using two EPR methods: the calibration-curve method and the additive-dose method. The variation of the estimated EPR dose with tooth position is investigated by using eight teeth taken from the same person. Contribution of the dental X-ray treatments to the enamel-absorbed dose was evaluated using another 17 teeth exposed from 1 to 10 times.

  2. EPR of Mo3+ ions in lutetium aluminium garnet single crystals

    International Nuclear Information System (INIS)

    The EPR spectra of Mo3+ ions have been investigated in lutetium-aluminium garnet at ν=9.35 GHz and T=77 K. Mo3+ ions have been shown to isomorphically substitute A3+ ions in the octahedron coordination. Due to high splitting in the zero field only one transition -1/2 +1/2 is observed. The constants of the spin-hamiltonian describing the experimental data have been determined, and also the causes of broadening the EPR signal of Mo3+ ions in luteaium-aluminium garnet as compared to yttrium-aluminium garnet have been discussed

  3. EPR detection of the flux distribution in ceramic high-T c superconductors

    Science.gov (United States)

    Rakvin, B.; Požek, M.; Dulčić, A.

    1989-10-01

    EPR measurements were made on adsorbed diphenyl picrylhydrazil (DPPH) at the surface of a ceramic high- T c superconductor YBa 2Cu 3O 7. A significant broadening of the EPR linewidth was observed below the superconducting transition temperature T c. It is interpreted as a broadening due to the spatial distribution of the flux in the superconducting mixed state which is developed at the resonant magnetic field H 0 (H Cl ≪ H 0 ≪ H C2). The penetration depth of the magnetic field can be determined by this simple technique.

  4. Detection by EPR method of radiation treatment in dried fruits containing crystalline sugar

    International Nuclear Information System (INIS)

    The results of EPR (electron paramagnetic resonance) measurements are presented on the detection ability and stability of radiation induced sugar-born radicals in the samples of dried (dehydrated) fruits available in the market and related to doses of 0.5, 1 and 3 kGy, respectively. The experiments have been conducted during 12 months of storage. Measurements were done with an EPR - 10 MINI spectrometer in X band (frequency of microwaves 9.5 GHz), St. Petersburg Instruments Ltd. The aim of the work was to prove the reliability of acceptability of the method in routine control of irradiated food. (author)

  5. Network for collection of teeth for retrospective EPR dosimetry in Ukraine

    International Nuclear Information System (INIS)

    Network for collection of liquidators teeth had been established in Ukraine by joint efforts of SCRM AMSU and the Ministry of Health, substantial support is being received from international projects, in particular from the German-French Initiative Chernobyl. It ensures the accumulation of the dosimetric specimens and provides necessary conditions for wide scale application of the retrospective EPR dosimetry with tooth enamel. The high precision doses reconstructed for Chernobyl liquidators by the means of EPR dosimetry may be used for validation of other dosimetry techniques and verification of existing dose records for variety of epidemiological applications. (authors)

  6. Regulatory aspects of Olkiluoto 3 nuclear power plant (EPR-1600) (Draft, 12 Sept. 2005)

    International Nuclear Information System (INIS)

    A 1600 MWe European Pressurized Water Reactor (EPR) supplied by the Framatome ANP - Siemens Consortium is under construction at the Olkiluoto site in Finland. Current international safety requirements and especially French and German operating experience have been applied in the design. Finnish requirements and operating experience have also been applied, especially regarding site-specific features. Severe accidentmanagement and protection against a collision of a large passenger airplane are implemented in the plant design. The plant safety features, licensing procedure, Finnish regulatory requirements, changes to the original EPR design, project quality management and regulatory control are discussed. (author)

  7. Automated Spectral Manipulation and Data Analysis for EPR Dosimetry of Teeth

    International Nuclear Information System (INIS)

    A method for automating the spectral manipulation and data analysis procedures for EPR dosimetry of teeth is presented. The method is shown to correlate with conventional spectral peak-to-peak values to within 10 mGy for the reconstructed doses. Paired difference t-test data show that definitive systematic differences exist but that these effects on the reconstructed dose accuracy and precision are negligible for typical applications in tooth enamel EPR dosimetry. The algorithm is written in Hypercard script for Macintosh computers but could be implemented on other platforms (author)

  8. Zigzagging causility model of EPR correlations and on the interpretation of quantum mechanics

    International Nuclear Information System (INIS)

    Being formalized inside the S-matrix scheme, the zigzagging causility model of EPR correlations has full Lorentz and CPT invariance. EPR correlations, proper or reversed, and Wheeler's smoky dragon metaphor are respectively pictured in a spacetime or in the momentum-energy space, as V-shaped, anti LAMBDA-shaped, or C-shaped ABC zigzags, with a summation at B over virtual states absolute value B>=*. The reversibility = * implies that causality is CPT-invariant, or arrowless, at the microlevel. Arrowed causality is a macroscopic emergence, corollary to wave retardation and probability increase. Factlike irreversibility states repression, not suppression, of blind statistical retrodiction- that is, of final cause

  9. Characteristics and economy of the European reactor of pressurized water (EPR); Caracteristicas y economia del reactor europeo de agua a presion (EPR)

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz V, J.; Ramirez S, J.R.; Palacios H, J.C. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)]. e-mail: jov@nuclear.inin.mx

    2005-07-01

    The high current costs of the fossil fuels, have propitiated that the industries of electric power generation in the world reconsider the nuclear option as medium of generation. In Europe, the more recently contracted nuclear power plant is that of Olkiluoto-III in Finland that waits it enters in operation at the end of 2009. The reactor that will be installed in this power plant will be a prototype of pressurized water reactor of the companies AREVA and EDF. In this work they are described the reactor EPR and the major components of the nuclear power plant as well as the main characteristics of safety and the flexibility of the operation of the EPR. The supposed costs reported in different sources of information are also described and calculated with information provided by the manufacturer company. (Author)

  10. Polypropylene/ethylene-propylene rubber (PP/EPR blends for the automotive industry: Basic correlations between EPR-design and shrinkage

    Directory of Open Access Journals (Sweden)

    G. D. Potter

    2014-04-01

    Full Text Available The influence of the phase morphology on the shrinkage of injection molded plates from reactor based PP/EPR blends was investigated using a model series. The morphology of the dispersed phase – in terms of size and shape of the rubber particles as determined from scanning electron microscopy (SEM – was found to correlate fairly well with the shrinkage determined in the flow and transverse direction of injection molded plates. In this respect it turned out to be elementary to consider the anisotropy of the particles rather than their average size alone. Additionally, the effect of the EPR design on the coefficient of linear thermal expansion (CLTE was evaluated and brought into a relationship with the blend morphology.

  11. Modelo conceptual de datos difusos de triaje para emergencia hospitalaria representado con FuzzyEER

    Directory of Open Access Journals (Sweden)

    Wuilfredo Rangel

    2010-05-01

    Full Text Available El triaje de emergencia persigue desarrollar el proceso de valorización clínica preliminar para ordenar los pacientes según el nivel de urgencia o gravedad, antes de la atención médica, de forma que en una condición de saturación del servicio o disminución de recursos, los pacientes más graves sean tratados con prioridad. Un proceso de triaje presenta un alto grado de imprecisión o incertidumbre al momento de expresar el estado de salud de un paciente, en consecuencia puede haber dificultad y riesgo en la clasificación de las urgencias. En los servicios de emergencias de loshospitales públicos venezolanos, en especial el servicio de emergencia del Hospital Universitario de Caracas (HUC, seha evidenciado un incremento en el número de casos que se atienden, siendo una constante la saturación del servicio, lo cual imposibilita que los pacientes con prioridad de atención, sean tratados más rápidamente de forma oportuna y eficaz. En este trabajo se propone un modelo conceptual de datos difuso de triaje para el sector salud venezolano basado en el proceso de triaje hospitalario de la Sociedad Venezolana de Medicina de Emergencia y Desastres (SVMED, ya que un modelo de datos que contemple la representación de atributos difusos puede representar de mejor forma los requerimientos del sistema. El modelo propuesto utiliza la notación Entidad Relación con elementos difusos (FuzzyEER para la representación de las entidades y atributos con imprecisión. Dicho modelo será la base de un sistema automatizado de triaje que hará uso del lenguaje de consultas difusas FSQL (Fuzzy SQL.

  12. Research field development ou iron-sulfur proteins by the Moessbauer spectroscopy and EPR

    International Nuclear Information System (INIS)

    A research line on iron sulfides (chemical and structurally seemed with the iron-sulfur proteins), implanted and developed at CBPF-Brazil, using the same theoretical and experimental models used in the development of the research field on iron-sulfur proteins is reported. The techniques used are Moessbauer spectroscopy and EPR. (L.C.)

  13. EPR safety. Consideration of the internal and external hazards in the safety studies

    International Nuclear Information System (INIS)

    The author presents the main points of the Preliminary Safety Report of EDF on the EPR reactor safety. It concerns the considerations of the internal (fire, flood, explosions, pipes failures) and external (earthquakes, airplane falls, explosions, exceptional natural disasters, extreme meteorological conditions) damages. It presents how the safety report takes into account the aggression. (A.L.B.)

  14. Sonoporation enhances liposome accumulation and penetration in tumors with low EPR.

    Science.gov (United States)

    Theek, Benjamin; Baues, Maike; Ojha, Tarun; Möckel, Diana; Veettil, Seena Koyadan; Steitz, Julia; van Bloois, Louis; Storm, Gert; Kiessling, Fabian; Lammers, Twan

    2016-06-10

    The Enhanced Permeability and Retention (EPR) effect is a highly variable phenomenon. To enhance EPR-mediated passive drug targeting to tumors, several different pharmacological and physical strategies have been evaluated over the years, including e.g. TNFα-treatment, vascular normalization, hyperthermia and radiotherapy. Here, we systematically investigated the impact of sonoporation, i.e. the combination of ultrasound (US) and microbubbles (MB), on the tumor accumulation and penetration of liposomes. Two different MB formulations were employed, and their ability to enhance liposome accumulation and penetration was evaluated in two different tumor models, which are both characterized by relatively low levels of EPR (i.e. highly cellular A431 epidermoid xenografts and highly stromal BxPC-3 pancreatic carcinoma xenografts). The liposomes were labeled with two different fluorophores, enabling in vivo computed tomography/fluorescence molecular tomography (CT-FMT) and ex vivo two-photon laser scanning microscopy (TPLSM). In both models, in spite of relatively high inter- and intra-individual variability, a trend towards improved liposome accumulation and penetration was observed. In treated tumors, liposome concentrations were up to twice as high as in untreated tumors, and sonoporation enhanced the ability of liposomes to extravasate out of the blood vessels into the tumor interstitium. These findings indicate that sonoporation may be a useful strategy for improving drug targeting to tumors with low EPR. PMID:26878973

  15. Identification and dose assessment of irradiated cardamom and cloves by EPR spectrometry

    International Nuclear Information System (INIS)

    The use of electron paramagnetic resonance spectroscopy to accurately distinguish irradiated from unirradiated cardamom and cloves and assesses the absorbed dose to radiation processed cardamom and cloves are examined. The results were successful for identifying both irradiated and unirradiated cardamom and cloves. Additive reirradiation of cardamom and cloves produces reproducible dose–response functions, which can be used to assess the initial dose by back-extrapolation. Third degree polynomial function was used to fit the EPR signal/dose curves. It was found that this 3rd degree polynomial function provides satisfactory results without correction of decay for free radicals. The stability of the radiation induced EPR signal of irradiated cardamom and cloves were studied over a storage period of almost 8 months. The calculated G-value (The number of radicals per 100 eV of absorbed energy) for cardamom and cloves was found 0.07±0.01 and 0.055±0.01, respectively. - Highlights: • The EPR analysis of cardamom and cloves prove the sample has been irradiated or not. • Dose additive can be used for evaluation of the absorbed dose in cardamom and cloves. • The 3rd polynomial function can be used to fit the data and the estimated dose. • The stability of the radiation induced EPR signal of irradiated cardamom and cloves were studied over 2 months

  16. Irradiated bivalve mollusks: Use of EPR spectroscopy for identification and dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Alberti, Angelo, E-mail: aalberti@isof.cnr.it [CNR-ISOF, Area della Ricerca di Bologna, Via P. Gobetti 101, Bologna I-40129 (Italy); Chiaravalle, Eugenio [Istituto Zooprofilattico Sperimentale della Puglia e Basilicata, Via Manfredonia 20, Foggia I-71100 (Italy); Fuochi, Piergiorgio; Macciantelli, Dante [CNR-ISOF, Area della Ricerca di Bologna, Via P. Gobetti 101, Bologna I-40129 (Italy); Mangiacotti, Michele, E-mail: michelemangiacotti@libero.it [Istituto Zooprofilattico Sperimentale della Puglia e Basilicata, Via Manfredonia 20, Foggia I-71100 (Italy); Marchesani, Giuliana [Istituto Zooprofilattico Sperimentale della Puglia e Basilicata, Via Manfredonia 20, Foggia I-71100 (Italy); Plescia, Elena [CNR-ISOF, Area della Ricerca di Bologna, Via P. Gobetti 101, Bologna I-40129 (Italy)

    2011-12-15

    High energy radiation treatment of foodstuff for microbial control and shelf-life extension is being used in many countries. However, for consumer protection and information, the European Union has adopted the Directives 1999/2/EC and 1999/3/EC to harmonize the rules concerning the treatment and trade of irradiated foods in EU countries. Among the validated methods to detect irradiated foods the EU directives also include Electron Paramagnetic Resonance (EPR/ESR) spectroscopy. We describe herein the use of EPR for identification of four species of bivalve mollusks, i.e. brown Venus shells (Callista chione), clams (Tapes semidecussatus), mussels (Mytilus galloprovincialis) and oysters (Ostrea edulis) irradiated with {sup 60}Co {gamma}-rays. EPR could definitely identify irradiated seashells due to the presence of long-lived free radicals, primarily CO{sub 2}{sup -}, CO{sub 3}{sup 3-}, SO{sub 2}{sup -} and SO{sub 3}{sup -} radical anions. The presence of other organic free radicals, believed to originate from conchiolin, a scleroprotein present in the shells, was also ascertained. The use of one of these radicals as a marker for irradiation of brown Venus shells and clams can be envisaged. We also propose a dosimetric protocol for the reconstruction of the administered dose in irradiated oysters. - Highlights: > EPR spectroscopy is confirmed a valuable identification tool for irradiated mollusks. > A conchiolin-derived radical can be used as irradiation marker for some mollusks. > A reliable protocol is outlined for dose reconstruction of irradiated oysters.

  17. Irradiated bivalve mollusks: Use of EPR spectroscopy for identification and dosimetry

    International Nuclear Information System (INIS)

    High energy radiation treatment of foodstuff for microbial control and shelf-life extension is being used in many countries. However, for consumer protection and information, the European Union has adopted the Directives 1999/2/EC and 1999/3/EC to harmonize the rules concerning the treatment and trade of irradiated foods in EU countries. Among the validated methods to detect irradiated foods the EU directives also include Electron Paramagnetic Resonance (EPR/ESR) spectroscopy. We describe herein the use of EPR for identification of four species of bivalve mollusks, i.e. brown Venus shells (Callista chione), clams (Tapes semidecussatus), mussels (Mytilus galloprovincialis) and oysters (Ostrea edulis) irradiated with 60Co γ-rays. EPR could definitely identify irradiated seashells due to the presence of long-lived free radicals, primarily CO2-, CO33-, SO2- and SO3- radical anions. The presence of other organic free radicals, believed to originate from conchiolin, a scleroprotein present in the shells, was also ascertained. The use of one of these radicals as a marker for irradiation of brown Venus shells and clams can be envisaged. We also propose a dosimetric protocol for the reconstruction of the administered dose in irradiated oysters. - Highlights: → EPR spectroscopy is confirmed a valuable identification tool for irradiated mollusks. → A conchiolin-derived radical can be used as irradiation marker for some mollusks. → A reliable protocol is outlined for dose reconstruction of irradiated oysters.

  18. EPR Spectroscopy of Different Sol Concentration Synthesized Nanocrystalline-ZnO Thin Films

    Directory of Open Access Journals (Sweden)

    Manju Arora

    2015-01-01

    Full Text Available Nanocrystalline zinc oxide (nc-ZnO thin films were grown on p-type silicon substrate through spin coating by sol-gel process using different sol concentrations (10 wt.%, 15 wt.%, and 25 wt.%. These films were characterized by high resolution nondestructive X-ray diffraction (XRD, scanning electron microscopy (SEM with energy dispersive X-ray analysis (EDS attachment, and electron paramagnetic resonance (EPR techniques to understand variations in structural, morphological, and oxygen vacancy with respect to sol concentration. The film surface morphology changes from nanowall to nanorods on increasing sol concentration. EPR spectra revealed the systematic variation from ferromagnetic to paramagnetic nature in these nc-ZnO films. The broad EPR resonance signal arising from the strong dipolar-dipolar interactions among impurity defects present in nc-ZnO film deposited from 10 wt.% sol has been observed and a single strong narrow resonance signal pertaining to oxygen vacancies is obtained in 25 wt.% sol derived nc-ZnO film. The concentrations of impurity defects and oxygen vacancies are evaluated from EPR spectra, necessary for efficient optoelectronic devices development.

  19. EDF will set up its first European Pressurized water Reactor (EPR) in Flamanville

    International Nuclear Information System (INIS)

    The EDF decision to set up an European Pressurized water Reactor (EPR) in its Flamanville site is a second commercial success for this new generation of reactors and prefigure the replacement of some of these plants which begin to age. (O.M.)

  20. Application of jade samples for high-doses using the EPR technique

    International Nuclear Information System (INIS)

    Full text: The dosimeter characteristics of jade samples were studied for application in dosimetry. Jade is the common denomination of two silicates: jadeite, and actinolite, which belong respectively to the subclasses of pyroxenes and amphiboles. Green materials were acquired as jade with origin in New Zealand, Austria and USA. The dosimetric properties of these materials were already studied using the thermoluminescence technique, showing their potential use for high dose dosimetry. At the Metrology Laboratory of IPEN, Sao Paulo, glasses, sand and Brazilian natural stones have been studied in relation to their dosimetric properties for high-doses using different techniques. In the present work jade samples were studied using the electronic paramagnetic resonance (EPR) technique to investigate the potential applications in gamma radiation dosimetry. The EPR spectra of different jade samples were obtained after irradiation with different absorbed doses of 50 Gy up to 10 kGy. The jade samples present one g-factor at 2.010 that grows with the absorbed dose; it can be attributed to an electron center. The EPR spectra obtained of the USA jade samples and their main dosimetric properties as reproducibility, calibration curves and energy dependence were investigated. There is no evidence in the literature about jade applications in radiation dosimetry using the EPR technique; only crystallographic aspects of synthetic samples were compared to natural ones

  1. Oak Ridge Tokamak Experimental Power Reactor study, 1976. Part I. EPR summary

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, M.; McAlees, D.G.; Shannon, T.E.; Flanagan, C.A.; Lue, J.W.

    1977-04-01

    The study of the Tokamak Experimental Power Reactor (EPR) has been performed by the Oak Ridge National Laboratory (ORNL) for the Energy Research and Development Administration Division of Magnetic Fusion Energy (ERDA-DMFE) over a two-year period. This second year's work builds integrally upon the earlier efforts. Therefore, the following format has been adopted for this report. Part 1, entitled ''EPR Summary,'' contains a brief discussion of all facets of the work done this year. The technical areas discussed in Part 1 include the Reference Design itself; the underlying plasma engineering base; the supporting technical evaluations in the areas of magnet systems, nuclear engineering, and general engineering; and the major research, development, and demonstration needs that have been identified. Each of these areas is then discussed fully in separate technical memoranda, which have been issued as Parts 2-6. Where appropriate, the essential elements of previous interim reports have been included in order to provide a self-consistent, readable report. These earlier reports, Basic Considerations and Initiation of Studies (ORNL/TM-4853), EPR Scoping Study (ORNL/TM-5038), and EPR Reference Design (ORNL/TM-5042), can be consulted for a more complete discussion of the entire study.

  2. Application of EPR retrospective dosimetry for large-scale accidental situation

    Energy Technology Data Exchange (ETDEWEB)

    Skvortsov, V.G.; Ivannikov, A.I.; Stepanenko, V.F.; Tsyb, A.F.; Khamidova, L.G.; Kondrashov, A.E.; Tikunov, D.D

    2000-05-15

    Above 3000 tooth enamel samples, collected at population of radioactive contaminated territories after Chernobyl accident, the Chernobyl liquidators, the retired military of high radiation risk and the population of control radiation free territories were investigated by EPR spectroscopy method in order to obtain accumulated individual exposure doses. Results of EPR spectra measurements are stored in data bank; enamel samples are also stored in order to provide the possibility to repeat the measurements in future. Statistical analysis of results has allowed to detect the contribution into EPR signal in tooth enamel due to the action of the natural background radiation, and the radioactive contamination of territory. In general, the average doses of external exposure of the population obtained with EPR spectroscopy of teeth enamel are consistent with results based on other methods of direct and retrospective dosimetry. Essential exceeding of the individual doses above the average level within the population groups was observed for some persons. That gave the possibility to detect the individuals with overexposure, which were included into groups for medical monitoring.

  3. Investigations on resolution enhancement in EPR by means of electron spin echoes

    International Nuclear Information System (INIS)

    The electron spin echo technique has been applied in four types of experiments: the measurement of electric field induced shifts of the EPR line; the detection of electron spin echo ENDOR; a relaxation measurement and the measurement of hyperfine interactions via the nuclear modulation effect. (Auth.)

  4. Comparative study between two austenitic steels with the EPR (Electrochemical Potentiokinetic Reactivation) technique

    International Nuclear Information System (INIS)

    In the mid 19704s, the intergranular corrosion with stress corrosion cracking (IGSCC) have been identified as a greater problem in Boiling Water Reactors BWR in several places of the world. The Electrochemical Potentiokinetic Reactivation - Single Loop (EPR-SL) test and the Double Loop (EPR-DL) test, were developed as methods for measuring the Degree of Sensitization (DOS), show sensitised materials at subject to Intergranular Corrosion. In Mexico, the Laguna Verde4s reactor is BWR type and many of its principal components was built with AISI 304 stainless steels, while that in VVER reactors as well as Juragua4s reactor in Cuba is used 321 Stainless stell in its Russian equivalent designation 08Ch18N10T. In this work, were studied 304 and 08Ch18N10T stainless steels by means of EPR-SL, EPR-DL and ASTM A-262 techniques, they have been found a good correlation for 304 steel but not in 08Ch18N10T steel and was proposed one modification in the criterion by the evaluation on the sensitisation in this steels. Finally, both materials were welded with procedures used in the nuclear industry, by Slow Strain Rate Test (SSRT) to determine the Stress Corrosion Cracking SCC susceptibility, and subsequently the susceptibility to localized corrosion was studied by means of Cyclic Polarization test and the uniform corrosion rate in a solution with chlorides by the Tafel plot, Potentiodynamic Anodic Polarization Resistance. (Author)

  5. Interlaboratory comparison of EPR dose reconstruction results for russian nuclear workers

    International Nuclear Information System (INIS)

    We have conducted an EPR dose reconstruction study using tooth enamel of 24 teeth from Russian nuclear workers (Mayak Production Association) with known occupational exposure records. Mayak Production Association began operation in 1948 as the first industrial nuclear reactor of former Soviet Union and as a processing plant of spent nuclear fuels. Each tooth under present investigation was divided into two parts that were shared by at least two laboratories. Dose reconstruction was performed independently in 4 different laboratories located in Japan, Germany and Russia (2 laboratories) without prior knowledge on the recorded dose (double blind intercomparison). The results suggested the mean difference between EPR estimated dose of the paired samples of each tooth shared by the two laboratories in best agreement was 0.02 ± 0.15 Gy. Comparison of EPR results with dose from official records seemed to disclose the presence of at least two groups: one is modern workers (after 1961) who have reliable dosimetric information and can be used for the purposes of the verification of the dose reconstruction methods; the other is nuclear workers with high radiation doses (up to 5 Gy) that were received mainly before 1961. For the latter group, EPR doses tended to be lower than official dose indicating that cancer risk evaluations on this second group might be underestimated. (author)

  6. Characterization of lithium formate EPR dosimeters for high dose applications – comparison with alanine

    DEFF Research Database (Denmark)

    Waldeland, Einar; Helt-Hansen, Jakob; Malinen, Eirik

    2011-01-01

    Lithium formate and l-α-alanine (alanine) EPR dosimeters were irradiated to doses from 100 Gy to 100 kGy. The irradiations were mainly performed at a Gammacell irradiator with dose rate of approximately 5.5 kGy h−1. Both the peak-to-peak amplitude of the first derivative EPR spectrum and the area...... dosimeters irradiated to 1 kGy at temperatures from 11ºC to 40ºC were analyzed. By fitting an ‘exponential rise to maximum'-function to the dependence of the area under the EPR absorption spectrum on the dose, saturation doses of 53 kGy and 87 kGy for lithium formate and alanine, respectively, were found...... dosimeter signal per ºC change in irradiation temperature) were 0.154 % K−1 and 0.161 % K−1 for lithium formate and alanine, respectively. This work demonstrates that lithium formate EPR dosimeters may be suitable for high dose applications, but their signals saturate at lower doses than alanine. The...

  7. Recent revisions to MAAP4 for U.S. EPR severe accident applications

    International Nuclear Information System (INIS)

    A revision of the MAAP4 code (i.e., version 4.0.7) has been developed to address the severe accident evaluation needs of the U.S. EPR. The U.S. EPR design employs an ex-vessel severe accident strategy involving specific containment regions devoted to debris stabilization and long term cooling. The modifications performed to the MAAP4 code address both the phenomenological aspects and the spatial modeling flexibility consistent with MAAP4's Generalized Containment Model framework. In addition, enhancements have been included in MAAP4 to improve the modeling of other severe accident mitigation features and to improve code usage and level of detail available to the user. The implementation of several new models and enhancements into the MAAP4 code provides the necessary integral analysis capability of U.S. EPR severe accidents from the initiating event, through reactor vessel failure, to long-term containment and ex-vessel melt stabilization. This paper presents a detailed description of the code enhancements supporting the U.S. EPR design certification. (authors)

  8. High-frequency EPR and ENDOR spectroscopy on semiconductor quantum dots

    NARCIS (Netherlands)

    Baranov, P.G.; Orlinskii, S.B.; de Mello Donega, C.; Schmidt, J.

    2010-01-01

    It is shown that high-frequency electron paramagnetic resonance (EPR) and electron-nuclear double resonance (ENDOR) spectroscopy are excellent tools for the investigation of the electronic properties of semiconductor quantum dots (QDs). The great attractions of these techniques are that, in contrast

  9. A radical-bridged bis(ferrocenylcopper(I)) complex: Structural identity, multifrequency EPR, and spectroelectrochemistry

    Czech Academy of Sciences Publication Activity Database

    Roy, S.; Sieger, M.; Singh, P.; Niemeyer, M.; Fiedler, Jan; Duboc, C.; Kaim, W.

    2008-01-01

    Roč. 361, č. 6 (2008), s. 1699-1704. ISSN 0020-1693 R&D Projects: GA MŠk LC510; GA AV ČR IAA400400505 Institutional research plan: CEZ:AV0Z40400503 Keywords : copper compound * crystal structure * EPR spectroscopy * ferrocenes Subject RIV: CG - Electrochemistry Impact factor: 1.940, year: 2008

  10. Comparative EPR study CO2− radicals in modern and fossil tooth enamel

    International Nuclear Information System (INIS)

    Comparative EPR investigation of CO2− radicals in modern (γ-irradiated) and fossil samples of tooth enamel was performed. The samples studied were the enamel powders and plates, the latter demonstrating an orientation dependence of EPR spectra in an external magnetic field. It was found that the ratio between the axial and orthorhombic CO2− centers amounts appears to be different for modern and fossil enamels. This ratio can be estimated by modeling of EPR spectra lineshape of powders or, in the case of plates, from the orientation dependence of EPR spectra in an external magnetic field. It was assumed that the difference between modern and fossil enamels is caused by the transformation, in the course of time, of orthorhombic CO2− centers into axial ones. The equations that describe this process were deduced. Their solutions show that the ratio between the amounts of the axial and orthorhombic centers does not depend on the dose rate. This finding can be used for the development of the method to determine the fossil enamel age avoiding the determination of the annual dose. - Highlights: • Ratio CO2−(axial)/CO2−(orthorhombic) is different for modern and fossil enamels. • Difference is caused by the transformation CO2−(or) → CO2− (ax), during lifetime. • Ratio CO2− (ax)/CO2− (or) does not depend on the dose rate. • Opportunity of enamel age determination avoiding annual dose estimation is discussed

  11. Magnetic properties of single crystal alpha-benzoin oxime: An EPR study

    International Nuclear Information System (INIS)

    The electron paramagnetic resonance (EPR) spectra of gamma irradiated single crystals of alpha-benzoinoxime (ABO) have been examined between 120 and 440 K. Considering the dependence on temperature and the orientation of the spectra of single crystals in the magnetic field, we identified two different radicals formed in irradiated ABO single crystals. To theoretically determine the types of radicals, the most stable structure of ABO was obtained by molecular mechanic and B3LYP/6-31G(d,p) calculations. Four possible radicals were modeled and EPR parameters were calculated for the modeled radicals using the B3LYP method and the TZVP basis set. Calculated values of two modeled radicals were in strong agreement with experimental EPR parameters determined from the spectra. Additional simulated spectra of the modeled radicals, where calculated hyperfine coupling constants were used as starting points for simulations, were well matched with experimental spectra. - Highlights: ► Magnetic properties of alpha-benzoin oxime were investigated, which has not yet been studied by EPR. ► Two stable radicals were found out in the irradiated alpha-benzoin oxime single crystal. ► The behavior of the radicals produced by irradiation are interesting and considerable. ► The effect of irradiation on oxime derivatives is important because of their usage in life.

  12. Recent results of EPR and Moessbauer investigations on lattice dynamics in ammonium sulphate

    CERN Document Server

    Grecu, M N; Grecu, V V

    2003-01-01

    Recent results of the lattice dynamics investigation on ammonium sulfate are reported based on recent experiments carried out using using the non-destructive experimental technique of EPR and NGR. The main results confirm the presence and the contribution of a soft mode, which accompanied the paraferroelectric phase transition in the investigated crystal. (authors)

  13. Characteristic of paramagnetic centres in burnt clay and pottery by the EPR method

    International Nuclear Information System (INIS)

    The samples of natural clay and pottery have been investigated by using electron paramagnetic resonance (EPR) method. Because of young age (100-5000 years old) of these materials and the presence of iron compounds the big doses (1-200kGy) of irradiation have been used. The authors investigated whole material without quartz extracting from acid washing. In natural clay the EPR lines were observed which disappear after clay burning and they were also not present in EPR spectrum of pottery. After clay burning at temperatures similar to these at which pottery was burnt the spectra of clay became similar to pottery spectra. These EPR spectra have also similar hyperfine structure for which the g factors are equal g1=2.0595, g2=2.0079, and g3=2.0018 for clay and g1=2.0602, g2=2.0079 and g3=2.0019 for pottery. For these lines the [AlO4]0 centre in quartz was ascribed

  14. The acid-catalyzed interaction of melanin with nitrite ions. An EPR investigation

    OpenAIRE

    Matuszak Zenon; Chignell Collin F.; Reszka Krzysztof J.

    2015-01-01

    The interaction of synthetic dihydroxyphenylalanine (DOPA) melanin (DM) with nitrite ions, NO2−, in the pH 3.6–7.0 range, has been investigated using electron paramagnetic resonance (EPR). We found that especially at pH

  15. EPR and UV spectroscopic study of table sugar as a high-dose dosimeter

    International Nuclear Information System (INIS)

    The possibilities for the estimation of the absorbed dose for high-energy radiation with a new self-calibrated dosimeter containing table sugar as a radiation-sensitive material and Mn2+/MgO as an internal standard by the method of electron paramagnetic resonance (EPR) is reported. The dose response of this dosimeter is represented as the ratio between the EPR signal intensities of sugar and Mn2+ versus absorbed dose. Because the EPR spectra of both substances are simultaneously recorded, the influence of some related instrumental setting parameters were investigated. UV spectral studies on water solutions of irradiated solid sugar were also performed. In all solutions of irradiated sugar samples a band at 267 nm was recorded as linearly increasing intensity with the absorbed dose. The minimum detectable dose using the UV spectrum of water solutions of irradiated sugar is 100 Gy. Combination of EPR and UV spectral data is possible to use for independent internal or international calibration and control of dose estimations

  16. Study of EPR spectra of radicals from ionizing radiation interaction with alanine and 4-hydroxyproline samples

    International Nuclear Information System (INIS)

    A number of stable chemical radicals result following irradiation with ionizing rays of α-β-alanine and 4-hydroxyproline. They could be put into evidence using post-irradiation EPR technique. Analysis and inter-comparison of spectra signals become important for a correct assignment of structure and, subsequently of generating mechanisms in amino acids irradiated samples. (author)

  17. Investigation of vortex lattices in a high-temperature superconductor by the EPR decoration technique

    International Nuclear Information System (INIS)

    Results are presented of EPR studies carried out on the superconducting ceramics YBa2Cu3O7 and Tl2Ba2Ca2CuO10 and on single crystals of YBa2Cu3O7 coated (decorated) with the organic radical DPPH, which possesses a narrow EPR line. Inhomogeneous broadening of the DPPH line caused by the vortex lattice was observed for all samples below Tc. The value of the magnetic penetration depth λo and the behavior of λ(T) were extracted from the temperature dependence of the EPR linewidth. The values of λo obtained were 3900 Angstrom for Tl2Ba2Ca2Cu3O10, 3500 Angstrom for YBa2Cu3O7-δ, and 1200 Angstrom for the single crystals of YBa2Cu3O7-δ they are satisfactorily described by the law [1 - (T/Tc)4]-1/2. The experiments with single crystals of YBa2Cu3O7-δ confirm that vortex-lattice irregularities give the main contribution to the EPR linewidth below Tc and not shielding effects. 39 refs., 13 figs., 1 tab

  18. Measuring precarious employment in times of crisis: the revised Employment Precariousness Scale (EPRES in Spain

    Directory of Open Access Journals (Sweden)

    Alejandra Vives

    2015-09-01

    Conclusion: The revised version of the EPRES demonstrated good metric properties and improved sensitivity to worker vulnerability and employment instability among permanent workers. Furthermore, it was sensitive to increased levels of precariousness in some dimensions despite decreases in others, demonstrating responsiveness to the context of the economic crisis affecting the Spanish labour market.

  19. EPR study of charge compensation of chromium centers in the strontium titanate crystal

    Czech Academy of Sciences Publication Activity Database

    Badalyan, A. G.; Azamat, Dmitry; Babunts, R.A.; Neverova, E.V.; Dejneka, Alexandr; Trepakov, Vladimír; Jastrabík, Lubomír

    2013-01-01

    Roč. 55, č. 7 (2013), 1454-1458. ISSN 1063-7834 R&D Projects: GA ČR GAP108/12/1941 Institutional support: RVO:68378271 Keywords : EPR spectroscopy * SrTiO3:Cr crystal * chromium centers Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.782, year: 2013

  20. On the use of locally dense basis sets in the calculation of EPR hyperfine couplings

    DEFF Research Database (Denmark)

    Milhøj, Birgitte Olai; Hedegård, Erik D.; Sauer, Stephan P. A.

    2013-01-01

    The usage of locally dense basis sets in the calculation of Electron Paramagnetic Resonance (EPR) hyperne coupling constants is investigated at the level of Density Functional Theory (DFT) for two model systems of biologically important transition metal complexes: One for the active site in the c...

  1. On the use of Locally Dense Basis Sets in the Calculation of EPR Hyperfine Couplings

    DEFF Research Database (Denmark)

    Hedegård, Erik D.; Sauer, Stephan P. A.; Milhøj, Birgitte O.

    2013-01-01

    The usage of locally dense basis sets in the calculation of Electron Paramagnetic Resonance (EPR) hyperne coupling constants is investigated at the level of Density Functional Theory (DFT) for two model systems of biologically important transition metal complexes: One for the active site in the c...

  2. Electronic paramagnetic resonance (EPR) for the study of ascorbyl radical and lipid radicals in marine organisms.

    Science.gov (United States)

    González, Paula Mariela; Aguiar, María Belén; Malanga, Gabriela; Puntarulo, Susana

    2013-08-01

    Electron paramagnetic resonance (EPR) spectroscopy detects the presence of radicals of biological interest, such as ascorbyl radical (A(•)) and lipid radicals. A(•) is easily detectable by EPR even in aqueous solution at room-temperature. Under oxidative conditions leading to changes in total ascorbate (AH(-)) content, the A(•)/AH(-) ratio could be used to estimate early oxidative stress in the hydrophilic milieu. This methodology was applied to a wide range of aquatic systems including algae, sea urchin, limpets, bivalves and fish, under physiological and oxidative stress conditions as well. The A(•)/AH(-) ratio reflected the state of one part of the oxidative defense system and provided an early and simple diagnosis of environmental stressing conditions. Oxidative damage to lipids was assessed by the EPR-sensitive adduct formation that correlates well with cell membrane damage with no interference from other biological compounds. Probe instability, tissue metabolism, and lack of spin specificity are drawback factors for employing EPR for in vivo determination of free radicals. However, the dependability of this technique, mostly by combining it with other biochemical strategies, enhances the value of these procedures as contributors to the knowledge of oxidative condition in aquatic organisms. PMID:23485428

  3. Application of High Precision EPR Dosimetry with Teeth for Reconstruction of Doses to Chernobyl Populations

    International Nuclear Information System (INIS)

    An acute need for reliable dose estimates calls for development and implementation of high precision retrospective dosimetric techniques. Among others, maybe the most preferable approach is EPR dosimetry using tooth enamel as a natural lifetime dosemeter. During the past eight years a vast experience in the field of EPR dosimetry has been accumulated in SCRM. In this research, the main effort was put into providing the highest achievable accuracy and reproducibility of results as well as on reduction of labour intensity for the analyses. The technique developed in SCRM comprises sophisticated sample preparation procedures, analysis of EPR spectra using a Mn2+:MgO spectrometric standard, and individual calibration of dose response for each sample. Methods for taking into account confounding factors (e.g. medical X ray exposure, UV light effects and non-linearity of dose-response curves) and assessment of overall uncertainty of dose estimation were also developed. A systematic approach to ERP dosimetry of an exposed population also includes efforts on acquisition of teeth from Chernobyl clean-up workers on a national scale. So far, samples from more than 700 individuals collected in Ukraine, and doses to more than 300 liquidators have been reconstructed. Application of this EPR dosimetric system allowed verification of Chernobyl dosimetry and provided on-going biomedical research with reliable retrospective dose estimates. (author)

  4. Three-Party Simultaneous Quantum Secure Direct Communication Scheme with EPR Pairs

    Institute of Scientific and Technical Information of China (English)

    WANG Mei-Yu; YAN Feng-Li

    2007-01-01

    We present a scheme for three-party simultaneous quantum secure direct communication by using EPR pairs.In the scheme, three legitimate parties can simultaneously exchange their secret messages. The scheme is also proven to be secure against the intercept-and-resend attack, the disturbance attack and the entangled-andmeasure attack.

  5. Electron paramagnetic resonance (EPR investigations of laser induced free radicals in spring wheat grains

    Directory of Open Access Journals (Sweden)

    Jezierski A.

    1999-09-01

    Full Text Available Electron paramagnetic resonance (EPR spectroscopy was applied to the studies on free radicals in wheat grains. The stable free radicals normally present in cereal grains can be detected by EPR measurements. Concentrations of the radicals in investigated grains were in the order of 1016 spins/gram of dry mass. The single signal characteristic for oxygen-containing (semiquinone radicals at g=2.0047 was observed as a dominating EPR signal; a small admixture of an additional radical at g=2.006 was also detected. The He-Ne and semiconductor laser irradiadion of the grains (doses 10-5 to 10-1 J/cm2 resulted in a distinct increase of the stable radical concentration (signal at g=2.0046. The increase of 10 to 30% depending on the laser irradiation technique was measured; the dependence on the dose and the cultivar was less significant. The new radicals have transient character and EPR signal of the laser irradiated grains gradually decreases for several days to stabilize at the normal level of the radical concentration.

  6. Electron paramagnetic resonance (EPR) investigations of laser induced free radicals in spring wheat grain

    International Nuclear Information System (INIS)

    Electron paramagnetic resonance (EPR) spectroscopy was applied to the studies on free radicals in wheat grains. The stable free radicals normally present in cereal grains can be detected by EPR measurements. Concentrations of the radicals in investigated grains were in the order of 1016 spins/gram of dry mass. The single signal characteristic for oxygen-containing (semiquinone) radicals at g=2.0047 was observed as a dominating EPR signal; a small admixture of an additional radical at g=2.006 was also detected. The He-Ne and semiconductor laser irradiation of the grains (doses 10-5 to 10-1 J/cm2) resulted in a distinct increase of the stable radical concentration (signal at g=2.0046). The increase of 10 to 30% depending on the laser irradiation technique was measured; the dependence on the dose and the cultivar was less significant. The new radicals have transient character and EPR signal of the laser irradiated grains gradually decreases for several days to stabilize at the normal level of the radical concentration. (author)

  7. Quality assessment of information about medications in primary care electronic patient record (EPR systems

    Directory of Open Access Journals (Sweden)

    Maria Pous

    2010-06-01

    Conclusions This project highlighted the poor quality of drug information provided by these EPR programmes. The ten-item tool seems suitable for assessing their quality. Based on this analysis, we have proposed a set of ten quality standards for prescribing software.

  8. Producing the event ready two photon polarization EPR state with linear optics devices

    OpenAIRE

    Xiang-Bin, Wang

    2002-01-01

    We propose a scheme to produce the maximally two photon polarization entangled state(EPR state) with single photon sources and the linear optics devices. In particular, our scheme requires the photon detectors only to distinguish the vacuum and non-vacuum Fock number states. A sophisticated photon detector distinguishing one or two photon states is unnecessary.

  9. VO2+ ions in zinc lead borate glasses studied by EPR and optical absorption techniques.

    Science.gov (United States)

    Prakash, P Giri; Rao, J Lakshmana

    2005-09-01

    Electron paramagnetic resonance (EPR) and optical absorption spectra of vanadyl ions in zinc lead borate (ZnO-PbO-B2O3) glass system have been studied. EPR spectra of all the glass samples exhibit resonance signals characteristic of VO2+ ions. The values of spin-Hamiltonian parameters indicate that the VO2+ ions in zinc lead borate glasses were present in octahedral sites with tetragonal compression and belong to C4V symmetry. The spin-Hamiltonian parameters g and A are found to be independent of V2O5 content and temperature but changing with ZnO content. The decrease in Deltag( parallel)/Deltag( perpendicular) value with increase in ZnO content indicates that the symmetry around VO2+ ions is more octahedral. The decrease in intensity of EPR signal above 10 mol% of V2O5 is attributed to a fall in the ratio of the number of V4+ ions (N4) to the number of V5+ ions (N5). The number of spins (N) participating in resonance was calculated as a function of temperature for VO2+ doped zinc lead borate glass sample and the activation energy was calculated. From the EPR data, the paramagnetic susceptibility was calculated at various temperatures and the Curie constant was evaluated from the 1/chi-T graph. The optical absorption spectra show single absorption band due to VO2+ ions in tetragonally distorted octahedral sites. PMID:16043053

  10. Effect of spectrum processing procedure on the linearity of EPR dose reconstruction in tooth enamel

    International Nuclear Information System (INIS)

    Electron Paramagnetic Resonance (EPR) spectroscopy with tooth enamel is a widely used method of dosimetry. The accuracy of EPR tooth dosimetry depends on the spectrum processing procedure, the quality of which, in its turn, relies on instrumental noise and the signals from impurities. This is especially important in low-dose evaluation. The current paper suggests a method to estimate the accuracy of a specific spectrum processing procedure. The method is based on reconstruction of the radiation-induced signal (RIS) from a simulated spectrum with known RIS intensity. The Monte Carlo method was used for the simulations. The model of impurity and noise signals represents a composite residual spectrum (CRS) obtained by subtraction of the reconstructed RIS and the native background signal (BGS) from enamel spectra measured in HMGU (Neuherberg, Germany) and IMP (Yekaterinburg, Russia). The simulated spectra were deconvoluted using a standard procedure. The method provides an opportunity to compare the simulated “true” RIS with reconstructed values. Two modifications of the EPR method were considered: namely, with and without the use of the reference Mn2+ signals. It was observed that the spectrum processing procedure induces a nonlinear dose response of the reconstructed EPR amplitude when the height of the true RIS is comparable with the amplitudes of noise-like random splashes of CRS. The area of nonlinearity is below the limit of detection (DL). The use of reference Mn2+ signals can reduce the range of nonlinearity. However, the impact of the intensities of CRS random signals on nonlinearity is two times higher than the one observed when the reference signals were not used. The reproducibility of the software response is also dependent on both the amplitude of the CRS and the use of a reference signal, and it is also two times more sensitive to the amplitude of the CRS. In most EPR studies, all of the data are used, even those for which the dose value is lower

  11. Operating an EPR: A strong asset in the future European electricity market

    International Nuclear Information System (INIS)

    Recently, two nuclear units have been decided in Europe, both EPR 1,600 MWe. In Finland, TVO Company decided to commission a reactor in 2009 on Olkiluoto site. The license was granted in February 2005 and the construction started in summer. In 2004 in France, EDF Company decided an EPR to be commissioned in 2012 at Flamanville. In both cases, national Parliament vote has given the green light. It is interesting to understand why each company has made such decision. In TVO case, the main driving factor seems to be the need of industrial consumers for low and stable electricity price in a context of growing excess demand. In EDF case, no short term demand, but rather long term electricity company strategy seems to be the main reason. The relation to national energy policy is very clear in both cases. In Finland, the 5. Nuclear Power Plant was decided: - as a key element of the energy mix to meet growing electricity needs while replacing older plants, - to ensure, together with renewables, the fulfillment of the Kyoto commitments, - to secure stable and predictable electricity price for intensive industrial consumers (for instance, paper mills), - to reduce the dependence on electricity import. Here, it is argued more broadly that EPR will be a strong asset in the future European electricity market. To support this argument, we shall describe: 1) to what extent the evolving European electricity market may call for new nuclear units, 2) specific design features explaining why EPR especially fits with expectations, 3) cost assessments giving the conditions of EPR competitiveness, 4) main elements of risk assessment and how they are dealt with. (authors)

  12. Application of EPR spectroscopy to the examination of pro-oxidant activity of coffee.

    Science.gov (United States)

    Krakowian, Daniel; Skiba, Dominik; Kudelski, Adam; Pilawa, Barbara; Ramos, Paweł; Adamczyk, Jakub; Pawłowska-Góral, Katarzyna

    2014-05-15

    Free radicals present in coffee may be responsible for exerting toxic effects on an organism. The objectives of this work were to compare free radicals properties and concentrations in different commercially available coffees, in solid and liquid states, and to determine the effect of roasting on the formation of free radicals in coffee beans of various origins. The free radicals content of 15 commercially available coffees (solid and liquid) was compared and the impact of processing examined using electron paramagnetic resonance (EPR) spectroscopy at X-band (9.3 GHz). First derivative EPR spectra were measured at microwave power in the range of 0.7-70 mW. The following parameters were calculated for EPR spectra: amplitude (A), integral intensity (I), and line-width (ΔBpp); g-Factor was obtained from resonance condition. Our study showed that free radicals exist in green coffee beans (10(16) spin/g), roasted coffee beans (10(18) spin/g), and in commercially available coffee (10(17)-10(18) spin/g). Free radical concentrations were higher in solid ground coffee than in instant or lyophilised coffee. Continuous microwave saturation indicated homogeneous broadening of EPR lines from solid and liquid commercial coffee samples as well as green and roasted coffee beans. Slow spin-lattice relaxation processes were found to be present in all coffee samples tested, solid and liquid commercial coffees as well as green and roasted coffee beans. Higher free radicals concentrations were obtained for both the green and roasted at 240 °C coffee beans from Peru compared with those originating from Ethiopia, Brazil, India, or Colombia. Moreover, more free radicals occurred in Arabica coffee beans roasted at 240 °C than Robusta. EPR spectroscopy is a useful method of examining free radicals in different types of coffee. PMID:24423509

  13. EPR study of table sugar rod and powder as high dose dosimeters

    International Nuclear Information System (INIS)

    In order to improve the ease of sample handling, the reproducibility of signal detection and quantification, simple methods of incorporating a homogeneous mixture containing sugar powder (30%) with wax (35%) and rubber (35%) into rods has been adopted. The dose response, the time stability of the free radicals produced in table sugar dosimeters (in both rod and powder form) by gamma radiation and the effect of the temperature during irradiation were studied by EPR (Electron Paramagnetic Resonance). The peak-to-peak height (PPH) measurement of the EPR signal is studied as a function of the absorbed gamma dose in the range 0.1–58 kGy. For the two forms, a linear dependency is found between 0.1 and 26 kGy. At higher doses the EPR signal amplitude continues to grow but non-linear up to 58 kGy. The dependence of temperature during irradiation has been investigated in the temperature range 25–40 °C and the calculated correction coefficients were found (2.7 ± 0.2)% °C−1 and (1.5 ± 0.3)% °C−1, respectively, for powder and rod forms. The time stability of the stored sugar samples was investigated for 34 days at room temperature, a rapid decrease of EPR signal was showed immediately after irradiation followed by slowly decrease. - Highlights: ► We investigated the EPR dosimetric properties of γ-irradiated sucrose solid state. ► We compared the accuracy of rod and powder form. ► We studied temperature irradiation effect, fading, and repeatability.

  14. Electron paramagnetic resonance (EPR) study of free radicals in irradiated zinc poly methacrylate

    International Nuclear Information System (INIS)

    We report the analysis of the X-band EPR spectrum of the free radical species formed in Zn(II) polymethacrylate (Zn(II) PMA), after degradation was induced in this polymer by 60Co γ- radiation at room temperature. We begin by describing the synthesis and characterization of our samples and its polymerization before applying them several doses to induce degradation. Doses from 10 to 100 kGy in steps of 10 kGy were applied to the samples. At 10 kGy dose, the EPR spectrum shows the superimposed spectra of two species, namely: a typical pattern of an axially symmetrical singlet and a broad symmetric single line. The former can be attributed to peroxide radicals. After applying further doses, the EPR spectra of the samples display a series of superimposed lines on top of the mentioned axial singlet and the broad line. In these spectra, we recognize three sets of lines: a weak doublet, a quartet and quintet in addition to the already detected axially symmetrical line and the broad singlet. These can be assigned to scission radicals trapped in the polymeric matrix. - Highlights: • We describe the synthesis and characterization of Zn(II) PMA and its polymerization. • Degradation was induced in this polymer by 60Co γ- radiation at room temperatura. • We report the analysis of the X-band EPR spectrum of the free radicals formed. • EPR spectrum of the degraded polymer shows a superimposed spectra of 5 species. • These are assigned to peroxide and scission radicals trapped in the polymer matrix

  15. Effect of UV irradiation on free radicals in synthetic melanin and melanin biopolymer from Sepia officinalis – EPR examination

    OpenAIRE

    Zdybel Magdalena; Pilawa Barbara

    2015-01-01

    Free radicals in synthetic melanin and melanin from Sepia officinalis were studied by electron paramagnetic resonance (EPR) spectroscopy. The effect of time of ultraviolet (UV) irradiation on free radicals in these melanins was tested. The samples were exposed to UV during 15, 30, and 60 minutes. EPR spectra were measured with microwaves from an X-band (9.3 GHz) in the range of microwave power of 2.2–70 mW. The performed EPR examinations indicate that high concentrations (~1021–1022 spin/g) o...

  16. Comparative EPR Examination of Gentamicin, Kanamycin and Netilmicin Effects on Free Radicals in DOPA-Melan

    International Nuclear Information System (INIS)

    Free radical properties of DOPA-melanin and its complexes with gentamicin, kanamycin and netilmicin were studied by the use of electron paramagnetic resonance spectroscopy at Xband (9.3 GHz). Melanins demonstrate stable paramagnetism and ability to drugs binding. Interactions of melanins with aminoglycoside antibiotics are not well known so far. o-Semiquinone free radicals formed in melanin biopolymers may be responsible for toxic effects appearing during antibioticotherapy. In this work we compare changes in paramagnetic centers systems of DOPA-melanin - model eumelanin caused by binding of typical aminoglycoside antibiotics. DOPA-melanin was chosen for measurements, because it mainly exists in living organism. The EPR results for the individual drugs were presented in our earlier works. EPR measurements were performed by the use of EPR spectrometer with modulation of magnetic field 100 kHz produced by RADIOPA-Poznan. Microwave frequency was recorded. The first derivative EPR spectra were recorded with low microwave power 0.7 MW at room temperature. Free radical concentration, g-factor, and linewidths were determined. Ultramarine was used as a reference of concentration of paramagnetic centers. A ruby crystal permanently placed in the spectrometer cavity was the secondary reference. Area under the absorption curve was obtained by double integration of its first derivative. g-Factor was calculated from the resonance condition. The influence of microwave power in the range of 0.7-70 MW on EPR lines of DOPAmelanin and its complexes with the analysed antibiotics was tested. Changes of amplitudes and linewidths with increasing of microwave power were obtained. o-Semiquinone free radicals exist in all the studied melanin complexes. It was confirmed that aminoglycoside antibiotics generate additional o-semiquinone free radicals in melanin polymer. The relatively low amount of free radicals appears in melanin after complexing with netilmicin - an antibiotic which

  17. Determinación del tamaño racional del bloque para la estimación de los recursos minerales en el yacimiento “Mariel”

    Directory of Open Access Journals (Sweden)

    Orestes Gómez-González

    2011-12-01

    Full Text Available La calidad de la estimación de recursos minerales es uno de los temas más importantes en la industria geológica-minera actual. El desarrollo de los sistemas automatizados en este campo ha permitido un incremento en la calidad de las estimaciones en diferentes tipos de yacimientos, pero aún existen elementos de carácter subjetivo que influyen directamente en la precisión y exactitud de los cálculos, uno de ellos es el tamaño del bloque de estimación. Para la selección de éste se han utilizado fundamentalmente criterios de carácter económico y minero. En este trabajo se demuestra la influencia del tamaño del bloque de estimación en la precisión y exactitud de los recursos estimados, utilizando procedimientos conjuntos de estimación y simulación geoestadística. El procedimiento se aplica en el yacimiento Mariel de materia prima para cemento y la metodología propuesta puede ser aplicable a otros casos de estudio.

  18. Características de los usuarios del Centro de Recursos para el Aprendizaje y la Investigación de la Universidad de Cienfuegos

    Directory of Open Access Journals (Sweden)

    Aylén Pérez Borges

    2015-02-01

    Full Text Available Objetivo: Caracterizar a los usuarios del Centro de Recursos para el Aprendizaje y la Investigación (CRAI de la Universidad de Cienfuegos “Carlos Rafael Rodríguez”. Método: Se realizó un análisis bibliográfico de los términos relacionados con el estudio, un análisis de la metodología AMIGA, así como de las estadísticas que brinda el sistema automatizado de préstamos de esta biblioteca universitaria sobre los usuarios que más visitan el centro. Resultados: Se identificaron diversos grupos de usuarios a nivel de estudiantes, profesores, facultades, centros universitarios municipales, y centros de estudios; a la vez que dos grupos centrales: usuarios reales y potenciales. Conclusiones: Se conocieron algunas de las características de los usuarios del CRAI, partiendo de los grupos identificados por el centro, teniendo en cuenta aspectos como sus niveles educacionales e intereses. Se considera que un estudio más detallado puede quedar abierto para cumplimentar este objetivo a un nivel mayormente exhaustivo.

  19. High-field (high-frequency) EPR spectroscopy and structural characterization of a novel manganese(III) corrole

    OpenAIRE

    Bendix, Jesper; Gray, Harry B.; Golubkov, Galina; Gross, Zeev

    2000-01-01

    The X-ray structure, magnetic susceptibility, and high-field (high-frequency) EPR spectrum of manganese 5,10,15-tris(pentafluorophenyl) corrole unambiguously establish that the complex contains an isolated, slightly rhombic, manganese(III) center.

  20. Characterization of the factors having an influence on the evolution of the EPR signal of irradiated alanine

    International Nuclear Information System (INIS)

    EPR/alanine dosimetry has been used by the LNHB (Laboratoire National Henri Becquerel) since many years for applied metrology. This technic is based on the measurement of the EPR signal of the free radicals induced in alanine by irradiation. The aim of this work is to characterize the factors having an influence on the evolution of the amplitude of the EPR signal of irradiated alanine to limit the uncertainties on the determination of the absorbed dose. The first step of this work has been the choice of the dosimeter. A bibliographic study completed by experiments on the response of alanine isomers to the dose and on its stability with time has lead us to choose L-α-alanine powder as dosimeter. The influence of the recording parameter of the spectrometer on the characteristics of the EPR spectrum has then been studied. This has enabled us to optimize the recording conditions of EPR spectra. As the angular anisotropy of the EPR signal limits the measurements reproducibility, an experimental protocol has been defined to solve this problem. The repeatability of the measurements has been enhanced by modifying the spectrometer and using an internal standard constituted of single crystals of CuSO4.5H2O. As the amplitude of the EPR signal is sensitive to the measurement temperature, a method of normalization of the results to 20 C has been determined. We have studied the influence of an irradiation parameter and of environmental parameters. We have shown that the EPR signal amplitude increases with irradiation temperature. The EPR signal amplitude and its evolution vary strongly with storage conditions (temperature and moisture) of the dosimeter before and after irradiation. The presence of moisture in alanine powder leads to a loss of signal amplitude. The dosimeters exposition to light also entails a loss of amplitude. Oxygen does not influence the EPR spectrum of alanine. We have noticed that the EPR signal amplitude of samples stored in absence of moisture increases