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Sample records for resina compuesta condensable

  1. Cierre de diastema con resinas compuestas híbridas

    Directory of Open Access Journals (Sweden)

    Alain Manuel Chaple Gil

    Full Text Available El tratamiento para el cierre de diastemas fundamentalmente está enfocado a otorgar estética y salud periodontal. Los diastemas pueden ser resueltos con prótesis y ortodoncia, sin embargo, estas opciones generalmente requieren de preparaciones del tejido sano, incluyen procedimientos de laboratorio y aumentan el tiempo clínico. La utilización de resinas compuestas constituye una opción estética y funcional para estos casos en los que se requiere de mínima intervención sobre el tejido sano o de ninguna. El propósito de esta presentación es describir un caso de cierre de diastema central anterosuperior utilizando resinas compuestas híbridas. Una paciente femenina de 21 años de edad acude a consulta para tratarse un diastema central superior. Se le propuso realizarle un cierre con resina compuesta híbrida. Se aplicó consentimiento informado y se obtuvo aprobación. Se realizó resolución del diastema con técnica incremental con resina híbrida hasta lograr el punto de contacto cuidando la salud periodontal. Se planificó el tratamiento, se pulieron las superficies a incrementar, se aplicaron sistemas adhesivos y se aplicaron capas de resina hasta lograr el resultado deseado. Mejoró la estética y se logró la total satisfacción de la paciente. En este caso, los pasos de la técnica de restauración directa con incremento d4e resina compuesta híbrida fueron seguidos adecuadamente. Se logró el cierre del diastema y el restablecimiento del punto de contacto sin forzar la papila interdental.

  2. Estudio de minerales cubanos para la preparación de resinas compuestas

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    Rubén Álvarez-Brito

    2004-03-01

    Full Text Available Las resinas compuestas o composites se ubican entre los materiales restauradores que se emplean en la reparación de tejido dental dañado. Las cargas inorgánicas que se le incorporan a las resinas compuestas le confieren mejores propiedades físico-mecánicas. Se prepararon resinas compuestas autocuradas a base de Bis-GMA y dimetacrilato de tetraetilenglicol (TEEDGMA, utilizando como carga inorgánica minerales de cuarzo procedente de Santa Lucía y de El Cacahual, caolín de la Isla de la Juventud y sheridanita de Holguín. Los rellenos fueron tratados previamente con metacriloxipropiltrietoxisilano y aminopropiltrietoxisilano como agentes de acoplamiento. Se les determinó la distribución de tamaños de partículas antes y después del tratamiento, y se observó en todos los casos un aumento del tamaño de partícula luego del tratamiento. Además, se determinó el grado de blancura, correspondiendo el mayor valor al cuarzo de El Cacahual. Se realizaron análisis químicos para determinar cuantitativamente los óxidos de silicio, hierro, magnesio, calcio, aluminio y titanio, además plomo y cadmio. Las resinas preparadas con los rellenos fueron evaluadas mediante el ensayo de resistencia a la compresión y comparación de la coloración con resinas comerciales, y se encontró que las preparadas con cuarzo presentan mayor resistencia mecánica y mejor coloración.

  3. Evaluación del grado de sellado marginal y resistencia adhesiva de restauraciones de resina compuesta con adhesivo convencional en dentición primaria y definitiva

    OpenAIRE

    Monsalves Bravo, Silvia Isabel; Terrazas Soto, Pedro; Toro Urbina, Georgina; Bader Mattar, Marcelo

    2014-01-01

    El presente estudio evaluó el grado de sellado marginal y resistencia adhesiva de restauraciones de resinas compuestas confeccionadas con un sistema adhesivo de grabado y lavado en dentición primaria y definitiva. Para realizar ambos test se utilizaron 20 piezas primarias y 20 piezas definitivas. En resistencia al cizallamiento, los dientes fueron seccionados longitudinalmente y se les adhirió un cilindro de resina compuesta, utilizando la técnica adhesiva de grabado y lavado para ambas denti...

  4. Preparación y valoración de resinas compuestas para uso dental basadas en nuevas matrices orgánicas

    OpenAIRE

    Cuevas Suárez, Carlos Enrique

    2013-01-01

    Las resinas compuestas son materiales que se utilizan en una gran variedad de aplicaciones en odontología. Éstos materiales comprenden una combinación de varios monómeros bimetacrílicos, materiales de relleno y un sistema fotoiniciador. Desde su aparición, los materiales de éste tipo han mejorado significativamente sus propiedades físicas, mecánicas y de biocompatibilidad. A pesar de esto avances, hoy en día las resinas compuestas tienen limitaciones en su aplicación clínica; problemas como l...

  5. OPACIDAD Y TRANSLUCIDEZ DE DIFERENTES RESINAS COMPUESTAS DE ACUERDO A SU TAMAÑO DE PARTÍCULA Y SU APLICACIÓN CLÍNICA

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    Manuel Roberto Sarmiento Limas

    2012-01-01

    Full Text Available Propósito: El objetivo de este estudio fue determinar el grado de opacidad o translucidez de acuerdo a su tamaño de partícula que nos ofrecen las resinas compuestas para seleccionar cual es la ideal de acuerdo al grado de dificultad estética. Materiales Y Metodos: Se realizaron muestras de resina circunferenciales, distribuidos así: Filtek Z350 XT®, Premisa Direct®, Exthet-X HD®, Tetric N Ceram®, Helio Molar®, Vit-l-escense, Amleogen Plus®, Miris 2 ® y Brilliant NG ®. Y se realizaron lecturas de reflectancia y transmitancia a través del Espectrofotometro Cary 5000.  Resultados: Las muestras estudiadas presentan un comportamiento similar tanto en reflectancia como en transmitancia, encontrando dos extremos opuestos, uno hacia opacidad (dentinas y otro hacia translucidez (esmaltes, pero con un gran número de muestras con valores intermedios, y comportamiento similar que no permite clasificarlas como dentinas o esmaltes a pesar de la clasificación dada por cada marca. Amleogen Plus®, Vit - L- Escence® Y Esthet X HD®  son las marcas que presentan mayor diferencia en el comportamiento de sus esmaltes en comparación con sus dentinas, contrario a lo observado con Helio Molar®, Brilliant NG® y Tetric N Ceram®. En cuanto al tamaño de partícula no se encuentran diferencias significativas en su comportamiento. Finalmente, los datos obtenidos demuestran que existen dentinas con comportamiento de esmaltes y esmaltes con comportamientos de dentinas. Conclusiones: Existe diferencia significativa entre las masas de resina compuesta de dentina y esmalte, valoradas en relación a las variables de opacidad y translucidez a través reflectancia y transmitancia, entre las diferentes marcas y dentro de cada una de ellas.

  6. Uso de incrustaciones de resina compuesta tipo onlay en molares estructuralmente comprometidos Use of onlay-type composite resin inlays in structurally involved molars

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    Alberto Carlos Cruz González

    2012-03-01

    Full Text Available Las incrustaciones en resina compuesta son una alternativa de bajo costo ante los métodos de obturación directos, frente a las dificultades de la adaptación marginal y la ubicación de contactos proximales, porque permiten otorgar una mejor anatomía dental a la restauración y superar el fenómeno de contracción al polimerizar grandes capas de material por fuera de la cavidad dental. El objetivo del presente artículo fue exponer el uso de la resina compuesta bajo técnica indirecta como una alternativa de fácil manipulación y resultados clínicos considerables ante la afectación estructural de molares. Se presentaron dos casos clínicos de incrustaciones con resina compuesta de tipo inlay onlay en dos molares permanentes afectados estructuralmente, uno de ellos fue tratado endodónticamente. Para la obtención de un troquel de trabajo sobre el que se confecciona la incrustación bajo técnica incremental se obtienen modelos al impresionar con alginato la arcada de los dientes seleccionados, se realiza vaciado en silicona liviana del diente preparado y el resto en yeso piedra tipo III. El proceso de cementación en la cavidad bucal se lleva a cabo con cemento resinoso de doble curado. Las incrustaciones fueron sometidas a un control a los seis meses para evaluar los signos de filtración o desadaptación marginal mediante el secado con aire de la jeringa triple, explorador y radiografías periapicales, que mostraron ausencia de desadaptación o pigmentación marginal. Se concluyó que ante la afectación estructural de molares, las incrustaciones con resina compuesta bajo técnica indirecta fueron de fácil manipulación y se obtuvieron satisfactorios resultados clínicos.The composite resin inlays are a low cost alternative which seeks improvements to the direct filling methods meet the challenges of the marginal adaptation, location of proximal contacts, allows us to improve the restoration dental anatomy and overcome the phenomenon of

  7. OPACIDAD Y TRANSLUCIDEZ DE DIFERENTES RESINAS COMPUESTAS DE ACUERDO A SU TAMAÑO DE PARTÍCULA Y SU APLICACIÓN CLÍNICA

    Directory of Open Access Journals (Sweden)

    Manuel Roberto Sarmiento Limas

    2011-12-01

    Full Text Available Normal 0 21 false false false ES-CO X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabla normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin-top:0cm; mso-para-margin-right:0cm; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0cm; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin;} Propósito: El objetivo de este estudio fue determinar el grado de opacidad o translucidez de acuerdo a su tamaño de partícula que nos ofrecen las resinas compuestas para seleccionar cual es la ideal de acuerdo al grado de dificultad estética. Materiales Y Metodos: Se realizaron muestras de resina circunferenciales, distribuidos así: Filtek Z350 XT®, Premisa Direct®, Exthet-X HD®, Tetric N Ceram®, Helio Molar®, Vit-l-escense, Amleogen Plus®, Miris 2 ® y Brilliant NG ®. Y se realizaron lecturas de reflectancia y transmitancia a través del Espectrofotometro Cary 5000.  Resultados: Las muestras estudiadas presentan un comportamiento similar tanto en reflectancia como en transmitancia, encontrando dos extremos opuestos, uno hacia opacidad (dentinas y otro hacia translucidez (esmaltes, pero con un gran número de muestras con valores intermedios, y comportamiento similar que no permite clasificarlas como dentinas o esmaltes a pesar de la clasificación dada por cada marca. Amleogen Plus®, Vit - L- Escence® Y Esthet X HD®  son las marcas que presentan mayor diferencia en el comportamiento de sus esmaltes en comparación con sus dentinas, contrario a lo observado con Helio Molar®, Brilliant NG® y Tetric N Ceram®. En cuanto al tamaño de partícula no se encuentran diferencias significativas en su

  8. Influencia de la remoción químico-mecánica del "smearlayer" y la presencia de un adhesivo dentinario en la microfiltración de restauraciones de resina compuesta

    OpenAIRE

    Macorra García, José Carlos de la; Gómez Martínez, Ana; Gutiérrez Argumosa, B.

    1989-01-01

    Se presenta un estudio comparativo "in vitro" de la microfiltración en restauraciones de resina compuesta cuyos márgenes cavosuperficiales están situados por completo en cemento. Se compara la capacidad de sellado de un adhesivo dentinario (ScotchBond I) utilizado según la técnica habitual, sin acondicionar la dentina y empleando el sistema Caridex como acondicionador dentinario. Este último sistema no mejoró los resultados de microfiltración en las condiciones del estudio.// We present an...

  9. Factores determinantes que ejercen influencia sobre el redimiento clínico de restauraciones con resina

    OpenAIRE

    Lahoud Salem, Víctor

    2014-01-01

    Las resinas compuestas pertenecen a los materiales más modernos empleados en la odontología contemporánea. Representan un mejoramiento significativo sobre los primeros restauradores de tipo polímero que consistieron de resinas metacrílicos sin relleno, de calidad inferior, y han tenido muchas deficiencias y limitaciones, los resultados obtenidos con las resinas compuestas de la última generación han dado satisfacción tanto al paciente como al odontólogo debido a que ofrecen una estética supe...

  10. Condensers

    International Nuclear Information System (INIS)

    Andrieux, M.B.

    1984-01-01

    Characteristics of the condenser cooling waters of various French 900 MW nuclear power plants. Design and description of various types of condensers: condensers feeded directly with river water, condensers feeded by cooling towers, condensers feeded with sea water of brackish water. Presentation of the main problems encountered with the brass bundles (ammoniacal corrosion, erosion of the peripheral tubes, vibrations of the tubes), with the titanium bundles, with the tubular plates, the tubes-tubular plates assemblies, the coatings of the condenser water chamber (sea water), the vapor by-pass and with the air inlet. Analysis of the in service performances such as condensation pressure, oxygen content and availability [fr

  11. Avaliação clínica de restaurações de resina condensável após dois anos = Two-year clinical evaluation of condensable composite restoration

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    Meireles, Sonia Saeger

    2006-01-01

    Full Text Available O objetivo deste estudo foi avaliar a performance clínica de uma resina condensável, comparada com uma resina microhíbrida e amálgama em restaurações de dentes posteriores após dois anos. Foram confeccionadas 33 restaurações de Classes I e II, em 6 pacientes, alunos da FOUFPel. Cada paciente deveria apresentar, no mínimo, uma restauração de cada material, que seriam aleatoriamente distribuídas. Os critérios para avaliação clínica (USPHS modificado – amálgama e USPHS adaptado – restaurações de resina foram utilizados. As restaurações foram classificadas como clinicamente satisfatórias (Alfa & Bravo e insatisfatórias (Charlie & Delta. A análise estatística foi realizada através dos testes de Friedman e de Kruskal-Wallis. Não foram encontradas diferenças significativas entre os tempos investigados nem entre os materiais testados (p > 0,05. Conclui-se que a maioria das restaurações encontravam-se clinicamente aceitáveis após 2 anos de avaliação clínica

  12. Infiltración de resina como tratamiento mínimamente invasivo de lesiones de caries dental incipiente

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    Alain Manuel Chaple Gil

    Full Text Available La mínima intervención en cariología ha sido definida como la filosofía de cuidados estomatológicos que se encarga del tratamiento de la primera aparición, la detección temprana y el tratamiento de la caries dental. Una de las técnicas para el tratamiento temprano y detención de lesiones incipientes es la infiltración de resina. El objetivo es mostrar la utilidad de las resinas fluidas para la infiltración de un primer y segundo molar inferior permanentes con una lesión incipiente de caries dental. Se trata de un paciente masculino de 17 años de edad sin antecedentes patológicos, que acude a consulta estomatológica. En hemiarcada inferior izquierda se observaron manchas en forma de punto de color marrón oscuro cerca de la fosita central y en la estría vestibular del 36 y 37 respectivamente, que no presentaban más de 1 mm de profundidad. Se diagnosticaron lesiones de caries dental incipiente y se decidió realizar una infiltración con resina compuesta de baja viscosidad o fluida en consulta única. El uso de resinas compuestas fluidas es beneficioso en la infiltración de lesiones cariosas incipientes de esmalte, pues evita su propagación y sella las brechas de esmalte afectado. Es una técnica de mínima intervención en cariología, que propicia una solución inmediata para estos procesos y mayor sencillez para la solución de la enfermedad caries dental al equilibrar las expectativas estéticas y de mantenimiento de las estructuras dentarias sanas.

  13. Efecto del pH de los sitemas adhesivos autoacondicionantes sobre las características adhesivas de resinas compuestas.

    OpenAIRE

    Azócar Cabello, Teresa

    2015-01-01

    Objetivo: El presente estudio tiene como propósito analizar la ultraestructura microscópica de la dentina tratada con sistemas adhesivos autoacondicionantes de distinto pH. Métodos: 8 terceros molares humanos sanos fueron cortados horizontalmente para exponer dentina superficial y fueron distribuidos al azar en 4 grupos (n=2): Adper Single Bond 2 (SB), 3M ESPE, Go!, SDI (Go), pH leve, Adper Prompt L Pop, 3M ESPE (PLP), moderado, Xeno III, Dentsply (XE), fuerte. Se talló una cavidad clase I co...

  14. Lograr estética y función en el sector posterior con resinas compuestas

    OpenAIRE

    García Crimi, Graciela Edith

    2014-01-01

    La operatoria dental actual cuenta con un conocimiento más profundo de las diferentes estructuras dentarias que sumado al gran adelanto tecnológico y científico en la ciencia de los biomateriales; fruto de innumerables investigaciones, nos permiten contar hoy, con una nueva generación de materiales restauradores, lo que hace más crítico y exigente el conocimiento y análisis por parte del profesional, de las técnicas a efectuar, la realización depurada de procedimientos y l...

  15. Resistencia al cizallamiento de una resina compuesta al aplicar diferentes agentes blanqueadores y su efecto sobre la microestructura del esmalte

    OpenAIRE

    Cornejo Peña, María Antonieta

    2014-01-01

    Muchos han sido los estudios que se han reportado acerca del efecto de sustancias aclaradoras sobre la adhesión y estructura del esmalte, sin embargo, poco se ha reportado sobre las alteraciones morfológicas de la estructura exterior del esmalte después del blanqueamiento. A pesar de la reducción de la microdureza del esmalte se ha informado que esta alteración no es sólo por el procedimiento de blanqueamiento, sino también por el pH de la fórmula utilizada. Algunos estudios no han encontrado...

  16. Morteros y hormigones de resinas

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    Rodríguez, G.

    1973-07-01

    Full Text Available In this article, the growing use is explained of resins and plastics (PVC and others in building, replacing the standard binder which is cement, or filling passages of pieces of set and hard concrete, to improve 3 to 5 fold their compressive and tensile strengths. Likewise, some rules are given on dryness of the aggregates to be used, speed in form removal, greater adherence, easier to handle, price problems, not very fire-proof, etc. Use in facing frontages, industrial flooring, treating cracks and fissures by injecting resins, joints, etc.Se explica en este artículo la creciente utilización de las resinas y materiales plásticos (cloruro de polivinilo y otros en la construcción, sustituyendo al aglomerante normal que es el cemento, o rellenando canalículos de piezas de hormigón fraguado y endurecido, para mejorar su resistencia a la compresión y a la tracción unas 3 a 5 veces. Igualmente se dan algunas normas sobre sequedad de los áridos a emplear, rapidez de desencofrado, mayor adherencia, mejor manejabilidad, inconvenientes de precio, poca resistencia al fuego, etc. utilización en revestimientos de fachadas, solados industriales, tratamiento de grietas y fisuras: por inyección de resinas, juntas, etc.

  17. La oración compuesta en guambiano

    Directory of Open Access Journals (Sweden)

    1994-01-01

    Full Text Available L'ÉNONCÉ COMPLEXE EN GUAMBIANO. Le document est divisé en deux parties. La première partie, à titre d'introduction illustrative présente une synthèse générale de l'énoncé simple en Guambiano. La deuxième partie développe le thème central de l'article : l'énoncé complexe. Les différentes classes d'énoncés sont présentées dans l'ordre, les énoncés complexes par juxtaposition, par coordination par subordination. El documento está organizado en dos partes. En la primera, a manera de introducción ilustrativa, se hace una síntesis general sobre la oración simple en guambiano. En la segunda se desarrolla el tema objeto del artículo: la oración compuesta. En él se presentan las diferentes clases de oraciones complejas identificadas hasta el momento en su orden: oraciones yuxtapuestas, coordinadas y subordinadas. THE COMPOUND SENTENCE IN GUAMBIANO. The document is organized in two parts. In the first, as an introductive illustration, a general synthesis of the simple sentence in Guambiano is done. In the second, the core theme of the article is developed: the compound sentence. There, the different kinds of complex sentences identified up to the moment are presented. They are in their order: juxtaposed, coordinated and subordinated sentences.

  18. Clinical effect of Resina Draconis capsules on primary dysmenorrhoea

    African Journals Online (AJOL)

    Clinical effect of Resina Draconis capsules on primary dysmenorrhoea. Li Sun, Jia Wang. Abstract. Purpose: To examine the effectiveness of Resina Draconis capsules in the treatment of primary dysmenorrhoea. Methods: In total, 324 patients with primary dysmenorrhoea were randomly allocated to three groups based on ...

  19. Fechamento de Diastema com resina composta

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    Vanessa Schwarz

    2015-02-01

    Full Text Available A presença de diastemas na região de incisivos centrais e laterais superiores é considerado um fator antiestético altamente prejudicial do ponto de vista social. Os diastemas podem ser decorrentes da presença de inserção baixa do freio labial, presença de mesiodens, fatores genéticos ou mesmo estar ligado a doenças periodontais associadas ao tabagismo ou não. Contudo, podem comprometer a estética do sorriso substancialmente em função de sua extensão. Este trabalho descreve, através de um relato de caso clínico, a técnica de fechamento de diastema entre incisivos centrais e laterais superiores por meio de resinas compostas, realizado na faculdade de Odontologia da Faculdade Meridional (IMED. Concluiu-se que o uso de sistemas adesivos e resinas compostas, através de mínimas intervenções, podem proporcionar um melhor contorno aos dentes, resultando em um sorriso com aspecto mais estético e agradável.

  20. [Furfural degradation by filamentous fungus Amorphotheca resinae ZN1].

    Science.gov (United States)

    Wang, Xiaofeng; Zhang, Jian; Xin, Xiujuan; Bao, Jie

    2012-09-01

    Some degradation products from lignocellulose pretreatment strongly inhibit the activities of cellulolytic enzymes and ethanol fermentation strains, thus the efficient removal of the inhibitor substances ("detoxification") is the inevitable step for the biotransformation processes. In this study, the biological detoxification of furfural by a newly isolated fungus, Amorphotheca resinae ZN1, was studied and the metabolic pathways of furfural degradation was analyzed. The metabolic pathway of furfural degradation in A. resinae ZN1 was described as follows: first, furfural was quickly converted into the low toxic furfuryl alcohol; then the furfuryl alcohol was gradually converted into furfural again but under the low concentration under aerobic condition, which was not lethal to the growth of the fungi; furfural continued to be oxidized to furoic acid by A. resinae ZN1. It is likely that furoic acid was further degraded in the TCA cycle to complete the biological degradation of furfural. The present study provided the important experimental basis for speeding up the biodetoxification of furfural by A. resinae ZN1 and the rate-limiting step in the lignocellulose biotransformation to ethanol.

  1. Fingerprint analysis of Resina Draconis by ultra-performance liquid chromatography

    OpenAIRE

    Xue, Yudi; Zhu, Lin; Yi, Tao

    2017-01-01

    Background Resina Draconis, a bright red resin derived from Dracaena cochinchinensis, is a traditional medicine used in China. To improve its quality control approach, an ultra-performance liquid chromatography (UPLC) fingerprint method was developed for rapidly evaluating the quality of Resina Draconis. Methods The precision, repeatability and stability of the proposed UPLC method were validated in the study. Twelve batches of Resina Draconis samples from various sources were analyzed by the...

  2. Gradually varied flow in compound open channels; Flujo gradualmente variado en canales de seccion compuesta

    Energy Technology Data Exchange (ETDEWEB)

    Sotela Avila, Gilberto [Universidad Nacional Autonoma de Mexico (Mexico)

    2001-03-01

    The author shows that the computation of gradually-varied-flow profiles in prismatic compound channels involves the solution of the dynamic equation, but using the compound channel Froude number defined by Blalock and Sturm. The same equation is used for non-prismatic channels by dividing the channel into short reaches and carrying the computation step by step through an iterative process. [Spanish] El autor demuestra que los perfiles del flujo gradualmente variado en canales prismaticos de seccion compuesta se pueden determinar mediante la integracion de la llamada ecuacion dinamica, pero usando el numero de Froude definido por Blalock y Sturm para este tipo de canales. Cuando no son prismaticos, tambien se aplica la ecuacion de la energia por tramos y el calculo sigue un proceso iterativo una vez definidos los tirantes criticos multiples y la zona en que se desarrolla el perfil.

  3. Resinas quelantes amidoxímicas Amidoxime chelating resins

    Directory of Open Access Journals (Sweden)

    Fernanda M. B. Coutinho

    1999-12-01

    Full Text Available Resinas quelantes com grupos amidoxima foram sintetizadas por copolimerização em suspensão de acrilonitrila (AN e divinilbenzeno (DVB e subsequente modificação química dos grupos ciano por reação com hidroxilamina. Na copolimerização, a proporção de divinilbenzeno e o grau de diluição foram variados. Gelatina e carbonato de cálcio foram usados como estabilizadores de suspensão e sulfato de sódio foi adicionado para reduzir a solubilidade da acrilonitrila em água, por meio do efeito salting out. Os copolímeros de AN/DVB e as resinas amidoxímicas obtidos foram caracterizados por meio de densidade aparente, área específica, volume de poros e teor de nitrogênio. As resinas amidoxímicas foram também avaliadas em relação a capacidade de complexação de íons cobre.Chelating resins with amidoxime groups were synthesized by suspension copolymerization of acrylonitrile (AN and divinylbenzene (DVB and subsequent chemical modification of cyano groups by reaction with hydroxylamine. In the copolymerization, the proportion of divinylbenzene and the dilution degree were varied. Gelatin and calcium carbonate were used as suspension stabilizers and sodium sulphate was added in order to reduce acrylonitrile solubility in water, by salting out effect. The AN/DVB copolymers and amidoxime resins obtained were characterized by apparent density, surface area, pore volume and by the content of nitrogen. The amidoxime resins were also evaluated in relation to the complexation capacity of copper ion.

  4. Analysis of biodegradation performance of furfural and 5-hydroxymethylfurfural by Amorphotheca resinae ZN1

    Science.gov (United States)

    2014-01-01

    Background Furfural and 5-hydroxymethylfurfural (HMF) are the degradation products of lignocellulose during pretreatment operations and significantly inhibit the consequent enzymatic hydrolysis and fermentation processes. The biodetoxification fungus Amorphotheca resinae ZN1 had demonstrated its excellent capacity on degrading lignocellulose derived inhibitors and helped the fermentation processes to achieve high yield of ethanol and biochemicals. Analysis of the biological degradation performance of furfural and HMF by A. resinae ZN1 will provide essential information for their fast and complete removal from the pretreated lignocellulose materials and facilitate the consequent ethanol fermentation. Results The degradation performance of furfural and HMF by A. resinae ZN1 was investigated by capturing intermediate metabolic products at various culture conditions. A. resinae ZN1 converts furfural/HMF into furfuryl/HMF alcohols and furoic/HMF acids simultaneously at aerobic condition, and only the corresponding furfuryl/HMF alcohols are obtained at anaerobic condition. The existence of glucose accelerates the degradation rate of furfural and HMF by A. resinae ZN1 and the cell mass growth rate aerobically. Remarkably, glucose is not consumed before furfural or HMF is degraded to a low threshold concentration. The finding suggests that furfural or HMF has a substrate priority of utilization by A. resinae ZN1 than glucose. This property may help the detoxification of furfural and HMF to be operated without consuming glucose. Conclusions The biological degradation performance of furfural and HMF by A. resinae ZN1 was investigated experimentally. Oxygen supply is important on the complete biodegradation of furfural and HMF by A. resinae ZN1. Furfural or HMF has the priority of substrate utilization than glucose by A. resinae ZN1. This study provided important information for detoxification enhancement and strain modification. PMID:24708699

  5. The anticancer effects of Resina Draconis extract on cholangiocarcinoma.

    Science.gov (United States)

    Wen, Feng; Zhao, Xiangxuan; Zhao, Yun; Lu, Zaiming; Guo, Qiyong

    2016-11-01

    Cholangiocarcinoma (CCA) is a relatively rare, heterogeneous malignant tumor with poor clinical outcomes. Because of high insensitivity to chemotherapy and radiotherapy, there are no effective treatment options. Efforts to identify and develop new agents for prevention and treatment of this deadly disease are urgent. Here, we assessed the apoptotic cytotoxicity of Resina Draconis extract (RDE) using in vitro and in vivo assays and identified the mechanisms underlying antitumor effects of RDE. RDE was obtained via vacuum distillation of Resina Draconis with 75 % ethanol. The ethanol extract could inhibit CCA cell proliferation and trigger apoptotic cell death in both QBC939 and HCCC9810 cell lines in a time- and concentration-dependent manner. RDE treatment resulted in intracellular caspase-8 and poly (ADP-ribose) polymerase protease activation. RDE significantly downregulated antiapoptotic protein survivin expression and upregulated proapoptotic protein Bak expression. RDE also inhibited CCA tumor growth in vivo. We observed that human CCA tissues had much higher survivin expression than did paired adjacent normal tissue. Taken together, the current data suggested that RDE has anticancer effects on CCA, and that RDE could function as a novel anticancer agent to benefit patients with CCA.

  6. Water Condensation

    DEFF Research Database (Denmark)

    Jensen, Kasper Risgaard; Fojan, Peter; Jensen, Rasmus Lund

    2014-01-01

    The condensation of water is a phenomenon occurring in multiple situations in everyday life, e.g., when fog is formed or when dew forms on the grass or on windows. This means that this phenomenon plays an important role within the different fields of science including meteorology, building physics......, and chemistry. In this review we address condensation models and simulations with the main focus on heterogeneous condensation of water. The condensation process is, at first, described from a thermodynamic viewpoint where the nucleation step is described by the classical nucleation theory. Further, we address...

  7. Steam condenser

    International Nuclear Information System (INIS)

    Masuda, Fujio

    1980-01-01

    Purpose: To enable safe steam condensation by providing steam condensation blades at the end of a pipe. Constitution: When high temperature high pressure steam flows into a vent pipe having an opening under water in a pool or an exhaust pipe or the like for a main steam eacape safety valve, non-condensable gas filled beforehand in the steam exhaust pipe is compressed, and discharged into the water in the pool. The non-condensable gas thus discharged from the steam exhaust pipe is introduced into the interior of the hollow steam condensing blades, is then suitably expanded, and thereafter exhausted from a number of exhaust holes into the water in the pool. In this manner, the non-condensable gas thus discharged is not directly introduced into the water in the pool, but is suitable expanded in the space of the steam condensing blades to suppress extreme over-compression and over-expansion of the gas so as to prevent unstable pressure vibration. (Yoshihara, H.)

  8. Emprego de resina epóxi em vigas danificadas de madeira de Pinus elliottii

    Directory of Open Access Journals (Sweden)

    Marília da Siva Bertolini

    Full Text Available A utilização da madeira em estruturas está vinculada a condições que permitam sua utilização por muitos anos sem a perda de suas propriedades de resistência e de rigidez. Entretanto, por se tratar de material natural, as estruturas em madeira projetadas podem estar sujeitas ao ataque de agentes biológicos, ação de intempéries, entre outros fatores, requerendo soluções na forma de reparo ou reforço. O presente trabalho objetivou investigar a influência do uso de resina epóxi como agente reparador em vigas danificadas de madeira de Pinus elliottii no cálculo do produto de rigidez à flexão. Para tanto, foi realizado um planejamento experimental completo, tendo a posição dos defeitos provocados (central ou laterais, o uso ou não da resina nos defeitos, e a posição desses defeitos (superior - compressão ou Inferior - tração como fatores. Os resultados da análise estatística revelaram que o uso da resina epóxi nas regiões danificadas das vigas apresentaram valores do produto de rigidez na flexão significativamente superiores quando comparados com as vigas da condição com defeito e sem a resina epóxi. Mesmo sendo significativo o uso da resina nas regiões danificadas, o produto de rigidez à flexão das vigas reparadas foi inferior ao produto de rigidez à flexão das vigas sem defeito (referência, evidenciando a necessidade de outros estudos com outras resinas e outros materiais visando à recuperação total da rigidez da peça de madeira danificada.

  9. ESTUDO DA RETENÇÃO ENTRE RESINA ACRÍLICA PARA BASE DE DENTADURA E DENTES DE RESINA ACRÍLICA

    Directory of Open Access Journals (Sweden)

    FAJARDO Renato Salviato

    1997-01-01

    Full Text Available Foi avaliada a resistência de união entre dentes e base de dentadura, ambos de resina acrílica. Os dentes foram incluídos em blocos cilíndricos de resina e, posteriormente, torneados, para se obterem cilindros de 5mm de diâmetro. Sobre a extremidade do dente, era adaptado um padrão de cera de mesmo diâmetro, que, após inclusão na mufla, era substituído por resina acrílica termicamente ativada pelo método de processamento convencional de base de dentadura. Como variáveis, usaram-se duas marcas de dentes, duas fases de inclusão (plástica e borrachóide e aplicação ou não de detergente e monômero sobre os dentes. Os corpos-de-prova, antes dos ensaios de ruptura por tração, foram armazenados em água destilada, a 37ºC, por 2 semanas. Os resultados mostraram que: marca de dente e fase de condensação não influíram nos resultados; somente o uso de detergente ou de monômero aumenta a retentividade e o seu uso conjunto apresenta efeito acumulativo.

  10. Sensibilización a bisfenol A y bisfenol F en trabajadores expuestos a resinas epoxi

    Directory of Open Access Journals (Sweden)

    L. Jiménez Bajo

    2008-06-01

    Full Text Available Las aplicaciones de las diferentes resinas epoxi basadas en bisfenol A y F son extensas. Las resinas epoxi basadas en bisfenol F son más nuevas y resistentes que las de bisfenol A, y ambas son causa conocida de dermatitis de contacto alérgica. Se estudian 39 casos de sensibilización a resinas epoxi en los últimos 5 años. Los resultados obtenidos son: prevalencia de sensibilización a resinas epoxi entre los pacientes estudiados del 2%, 27 varones y 8 mujeres, con una edad media de 42.77, un período de medio sensibilización de 23,8 meses. La sensibilización a bisfenol F desde que se incluye para las pruebas del parche en la batería de resinas epoxi es del 100% para los casos sensibilizados a la resina. La localización mayoritaria se dio en las manos, con una relevancia actual del 84%. Se recomendó un cambio de puesto en el trabajo al 46% de estos pacientes. El aumento de la sensibilización encontrada a bisfenol F puede explicarse por una sensibilización concomitante con bisfenol A, una declaración incorrecta de la composición de la resina o una reactividad cruzada de ambos.The applications of epoxy resins based on bisphenol A and F are extensive. Epoxy resins based on bisphenol F are new and more resistant than epoxy resins based on bisphenol A. Both of them cause allergic contact dermatitis. In the last 5 years, we have studied 39 cases of sensitization to epoxy resin. The results of our study were these: the global prevalence of epoxy resin sensitization was 2%, 27 men and 8 women. The mean age was 42.77 years and the sensitization period was 23.8 months. The most frequent localization of the lesions were hands (84% of the patients. Since bisphenol F was included in epoxy resin battery for patch testing, a 100% of positives responses in patients sensitized to epoxy resin have been found. Sensitization to epoxy resins was a cause of change in workplace in 46% of cases in our series. There has been an increase in sensitization of

  11. Polariton condensates

    International Nuclear Information System (INIS)

    Snoke, David; Littlewood, Peter

    2010-01-01

    Most students of physics know about the special properties of Bose-Einstein condensates (BECs) as demonstrated in the two best-known examples: superfluid helium-4, first reported in 1938, and condensates of trapped atomic gases, first observed in 1995. (See the article by Wolfgang Ketterle in PHYSICS TODAY, December 1999, page 30.) Many also know that superfluid 3 He and superconducting metals contain BECs of fermion pairs. An underlying principle of all those condensed-matter systems, known as quantum fluids, is that an even number of fermions with half-integer spin can be combined to make a composite boson with integer spin. Such composite bosons, like all bosons, have the property that below some critical temperature--roughly the temperature at which the thermal de Broglie wavelength becomes comparable to the distance between the bosons--the total free energy is minimized by having a macroscopic number of bosons enter a single quantum state and form a macroscopic, coherent matter wave. Remarkably, the effect of interparticle repulsion is to lead to quantum mechanical exchange interactions that make that state robust, since the exchange interactions add coherently.

  12. FUNCIONALIZACIÓN DE UNA RESINA DE INTERCAMBIO IONICO PARA LA PRECONCENTRACION DE Hg(II

    Directory of Open Access Journals (Sweden)

    Cecilia De Asmundis

    2011-01-01

    Full Text Available Se estudiaron las condiciones óptimas para funcionalizar una resina aniónica (Dowex 1X8 con un reactivo (difenilcarbazida específicamente adecuado para la determinación de Hg(II en soluciones acuosas. Se llevo a cabo el ajuste de las condiciones para la determinac ión del complejo Hg-DFC, las que permiten lograr un método eficaz, rápido y de bajo costo para detectar concentraciones de Hg en matrices complejas, mediante la realización de espectrofotometría de absorción UV-Vis en fase sólida. La resina puede ser utilizada para pre- concentrar Hg(II durante el pretratamiento para el análisis con métodos instrumentales específicos (absorción/emisión atómica. La intensidad del color desarrollado por la resina funcionalizada se encuentra estrechamente ligada con las concentraciones de Hg(II presentes en las muestras, lo que conduce a que el método pueda realizarse aún si no se tiene el equipamiento necesario, aplicando técnicas semi-cuantitativas como, colorimetria visual (naked eye.

  13. Avaliação in vitro da microinfiltração em cavidades classe II de molares decíduos, restaurados com resina composta auto e fotopolimerizável

    OpenAIRE

    CAVALCANTI Alessandro Leite; CHELOTTI Adolpho

    1999-01-01

    Estudou-se a microinfiltração marginal presente na interface da parede gengival de cavidades classe II em molares decíduos, restaurados com resina composta (auto e fotopolimerizável), através da penetração de uma solução corante. Os preparos cavitários apresentavam a parede gengival em esmalte e foram restaurados segundo 4 diferentes técnicas: 1) resina composta fotopolimerizável; 2) resina composta autopolimerizável; 3) resina composta auto e fotopolimerizável; e 4) ionômero de vidro/resina ...

  14. Condensation model for the ESBWR passive condensers

    International Nuclear Information System (INIS)

    Revankar, S. T.; Zhou, W.; Wolf, B.; Oh, S.

    2012-01-01

    In the General Electric's Economic simplified boiling water reactor (GE-ESBWR) the passive containment cooling system (PCCS) plays a major role in containment pressure control in case of an loss of coolant accident. The PCCS condenser must be able to remove sufficient energy from the reactor containment to prevent containment from exceeding its design pressure following a design basis accident. There are three PCCS condensation modes depending on the containment pressurization due to coolant discharge; complete condensation, cyclic venting and flow through mode. The present work reviews the models and presents model predictive capability along with comparison with existing data from separate effects test. The condensation models in thermal hydraulics code RELAP5 are also assessed to examine its application to various flow modes of condensation. The default model in the code predicts complete condensation well, and basically is Nusselt solution. The UCB model predicts through flow well. None of condensation model in RELAP5 predict complete condensation, cyclic venting, and through flow condensation consistently. New condensation correlations are given that accurately predict all three modes of PCCS condensation. (authors)

  15. Enhanced Condensation Heat Transfer

    Science.gov (United States)

    Rose, John Winston

    The paper gives some personal observations on various aspects of enhanced condensation heat transfer. The topics discussed are external condensation (horizontal low-finned tubes and wire-wrapped tubes), internal condensation (microfin tubes and microchannels) and Marangoni condensation of binary mixtures.

  16. Microdureza de caries incipientes artificiales infiltradas con resinas de baja viscosidad antes y después del termociclado

    OpenAIRE

    X. Zamorano Pino; V. Valenzuela Aránguiz; C. Vial Prado; M. Vidal Tardón

    2015-01-01

    Introducción: En Odontología Mínimamente Invasiva, el procedimiento denominado Infiltración de caries, pretende detener la progresión de las caries incipientes mediante el sellado de las microporosidades del esmalte afectado. Este tratamiento se realiza con la aplicación de resinas de baja viscosidad. El objetivo de este trabajo fue evaluar la microdureza superficial de caries incipientes artificiales infiltradas con resinas de baja viscosidad antes y después del proceso de termociclado. Meto...

  17. Comportamiento de canales como conectores de cortante para un sistema de Sección compuesta usando lámina colaborante

    OpenAIRE

    Huertas Muñoz, Juan Carlos

    2013-01-01

    Las secciones compuestas de acero y concreto se emplean con el fin de aprovechar las ventajas del acero a la tensión y el buen comportamiento del concreto ante esfuerzos de compresión. Lo que permite que ambos materiales trabajen al mismo tiempo y de forma eficiente son los conectores de cortante. Para realizar la función de conector de cortante se usan elementos como los espigos, canales, varilla en forma de bastón y en forma de U, entre otros que están siendo objeto de invest...

  18. Comportamiento de vigas de sección compuesta con perfiles de acero laminado y losa de concreto empleando conectores de cortante tipo tornillo grado dos (2)

    OpenAIRE

    García Zamora, Alejandro; Molina Herrera, Maritzabel

    2008-01-01

    En el presente artículo, partiendo de un análisis teórico-experimental, se determinan y caracterizan los parámetros de diseño que rigen el comportamiento de las vigas compuestas de perfiles de acero y losa de concreto empleando conectores de cortante tipo tornillo, dado que para esta clase de conector no existe un estudio específico de su comportamiento, además en la actualidad su diseño no está definido en las NSR-98, aunque es uno de los tipos de conectores más empleados en la construcción ...

  19. Comportamiento de vigas de sección compuesta con perfiles de acero laminado y losa de concreto empleando conectores de cortante tipo tornillo grado dos (2)

    OpenAIRE

    García Zamora, Alejandro; Molina Herrera, Maritzabel

    2010-01-01

    En el presente artículo, partiendo de un análisis teórico-experimental, se determinan y caracterizan los parámetros de diseño que rigen el comportamiento de las vigas compuestas de perfiles de acero y losa de concreto empleando conectores de cortante tipo tornillo, dado que para esta clase de conector no existe un estudio específico de su comportamiento, además en la actualidad su diseño no está definido en las NSR-98, aunque es uno de los tipos de conectores más empleados en la construcción ...

  20. Polymerization shrinkage evaluation of three packable composite resins using a gas pycnometer Avaliação da contração de polimerização de três resinas compactáveis, medida por picnômetro a gás

    Directory of Open Access Journals (Sweden)

    Ricardo Amore

    2003-09-01

    Full Text Available Modern restorative dentistry has been playing an outstanding role lately since composite resins, allied to adhesive systems, have been widely applied on anterior and posterior teeth restorations. The evolution of composite resins has mostly been verified due to the improvement of their aesthetic behavior and the increase in their compressive and abrasive strengths. In spite of these developments, the polymerization shrinkage inherent to the material has been a major deficiency that, so far, has been impossible to avoid. Using a gas pycnometry, this research investigated the polymerization shrinkage of three packable composite resins: Filtek P60 (3M, Prodigy Condensable (Kerr, and SureFil (Dentsply/Caulk, varying the distance from the light source to the surface of the resins (2 mm or 10 mm. The pycnometer Accupyc 1330 (Micromeritics, USA precisely records helium displacement, allowing fast and reliable measurements of the volume of composite resin immediately before and after polymerization, without interference of temperature or humidity. Results were not found to be statistically different for the three tested resins, either for 2 mm or 10 mm-distance from the light source to the composite surface.A Odontologia Restauradora moderna tem se destacado nos últimos anos e as resinas compostas, aliadas aos sistemas adesivos, têm sido muito empregadas para restaurações de dentes anteriores e posteriores. A evolução das resinas compostas tem sido constatada na melhoria do seu comportamento estético e no aumento da sua resistência à compressão e à abrasão. Apesar dos avanços mencionados, a contração de polimerização, inerente a esse material, continua sendo uma grande deficiência e, por enquanto, impossível de ser evitada. Nesta pesquisa a contração de polimerização de três resinas compostas compactáveis, Filtek P60 (3M, Prodigy Condensável (Kerr e SureFil (Dentsply/Caulk, variando-se a distância entre a fonte de luz e a

  1. Performance of evaporative condensers

    Energy Technology Data Exchange (ETDEWEB)

    Ettouney, Hisham M.; El-Dessouky, Hisham T.; Bouhamra, Walid; Al-Azmi, Bader

    2001-07-01

    Experimental investigation is conducted to study the performance of evaporative condensers/coolers. The analysis includes development of correlations for the external heat transfer coefficient and the system efficiency. The evaporative condenser includes two finned-tube heat exchangers. The system is designed to allow for operation of a single condenser, two condensers in parallel, and two condensers in series. The analysis is performed as a function of the water-to-air mass flow rate ratio (L/G) and the steam temperature. Also, comparison is made between the performance of the evaporative condenser and same device as an air-cooled condenser. Analysis of the collected data shows that the system efficiency increases at lower L/G ratios and higher steam temperatures. The system efficiency for various configurations for the evaporative condenser varies between 97% and 99%. Lower efficiencies are obtained for the air-cooled condenser, with values between 88% and 92%. The highest efficiency is found for the two condensers in series, followed by two condensers in parallel and then the single condenser. The parallel condenser configuration can handle a larger amount of inlet steam and can provide the required system efficiency and degree of subcooling. The correlation for the system efficiency gives a simple tool for preliminary system design. The correlation developed for the external heat transfer coefficient is found to be consistent with the available literature data. (Author)

  2. Condensation of steam

    International Nuclear Information System (INIS)

    Prisyazhniuk, V.A.

    2002-01-01

    An equation for nucleation kinetics in steam condensation has been derived, the equation taking into account the concurrent and independent functioning of two nucleation mechanisms: the homogeneous one and the heterogeneous one. The equation is a most general-purpose one and includes all the previously known condensation models as special cases. It is shown how the equation can be used in analyzing the process of steam condensation in the condenser of an industrial steam-turbine plant, and in working out new ways of raising the efficiency of the condenser, as well as of the steam-turbine plant as a whole. (orig.)

  3. Low pressure lithium condensation

    International Nuclear Information System (INIS)

    Wadkins, R.P.; Oh, C.H.

    1985-01-01

    A low pressure experiment to evaluate the laminar film condensation coefficients of lithium was conducted. Some thirty-six different heat transfer tests were made at system pressures ranging from 1.3 to 26 Pa. Boiled lithium was condensed on the inside of a 7.6-cm (ID), 409 stainless-steel pipe. Condensed lithium was allowed to reflux back to the pool boiling region below the condensing section. Fourteen chromel/alumel thermocouples were attached in various regions of the condensing section. The thermocouples were initially calibrated with errors of less than one degree Celsius

  4. Resistência à flexão de resinas de metacrilato de metila e bisacrilato de metila submetidas à termociclagem

    Directory of Open Access Journals (Sweden)

    Ataís Bacchi

    Full Text Available OBJETIVO: Verificar a resistência à flexão de quatro resinas utilizadas para a confecção de restaurações temporárias submetidas à termociclagem. MÉTODO: Foram utilizadas as resinas da marcas Luxatemp e Structur 2, à base de bisacrilato de metila, e as resinas das marcas Duralay e Alike, à base de metacrilato de metila. Vinte espécimes de cada material foram confeccionados e divididos em dois grupos, para serem submetidos às seguintes condições: (I - 24 horas de armazenagem em saliva artificial, e (II - 24 horas de armazenagem em saliva artificial seguida de termociclagem (2000 ciclos, 5 °C-55°C. Cada amostra foi levada ao teste de resistência à flexão em uma Máquina de Ensaios Universal (EMIC DL 10000 e os dados obtidos foram analisados pelo teste ANOVA (dois fatores e, em seguida, pelo teste Tukey (p < 0,05. RESULTADO: As resinas de bisacrilato apresentaram resultados superiores de resistência à flexão após ambos os tempos de armazenagem, não diferindo estatisticamente entre si após 24 horas (p = 0,3594. A resina Luxatemp apresentou os maiores valores de resistência à flexão após a termociclagem, sendo estatisticamente superior às demais. A termociclagem alterou as propriedades mecânicas de todas as resinas, diminuindo a sua resistência à flexão (p = 0,001. CONCLUSÃO: As resinas de bisacrilato apresentam maior resistência à flexão do que as resinas de metacrilato para os fatores estudados. Todos os materiais utilizados neste estudo tiveram sua resistência reduzida pela ciclagem térmica.

  5. Modelling of condensation phenomena

    International Nuclear Information System (INIS)

    Jeong, Jae Jun; Chang, Won Pyo

    1996-07-01

    Condensation occurs when vapor is cooled sufficiently below the saturation temperature to induce the nucleation of droplets. Such nucleation may occur homogeneously within the vapor or heterogeneously on entrained particular matter. Heterogeneous nucleation may occur on the walls of the system, where the temperature is below the saturation temperature. There are two forms of heterogeneous condensation, drop-wise and film-wise. Another form of condensation occurs when vapor directly contacts to subcooled liquid. In nuclear power plant systems, all forms of condensation may occur during normal operation or accident conditions. In this work the modelling of condensation is surveyed, including the Nusselts' laminar film condensation theory in 1916, Rohsenow's turbulent film condensation model in 1950s, and Chen's models in 1987. Major attention is paid on the film condensation models among various research results because of its importance in engineering applications. It is found that theory, experiment, and empirical correlations for film condensation are well established, but research for drop-wise and direct-contact condensation are not sufficient yet. Condensation models in the best-estimate system codes such as RELAP5/MOD3 and CATHARE2 are also investigated. 3 tabs., 11 figs., 36 refs. (Author)

  6. RESINAS COMPOSTAS EM DENTES POSTERIORES: UMA REVISÃO SISTEMÁTICA

    OpenAIRE

    Lima, Cláudia Fonseca de Albuquerque; de Souza, Fábio Barbosa; da Silva, Claudio Heliomar Vicente

    2016-01-01

    As resinas compostas vêm sendo largamente utilizadas em dentes posteriores. Objetivou-se realizar uma revisão sistemática acerca das publicações de avaliações clínicas do emprego deste material em restaurações que envolvessem a superfície oclusal e/ou proximal de pré-molares e molares de forma a avaliar os critérios empregados para execução das mesmas. As publicações foram selecionadas aleatoriamente a partir de uma pesquisa bibliográfica a partir dos pré-requisitos: publicação em revista ind...

  7. Resinas acetálicas: diversas aplicaciones en odontoestomatología

    OpenAIRE

    Puigpelat Martí, Ana M.; Casanellas Bassols, Josep M. (Josep Maria)

    1994-01-01

    La resina acetálica o Polioxime­tileno (POM) es un nuevo material estético de reciente aplicación en el campo de la Odontoestomatolo­gía. En este artículo presentamos al­gunas de las aplicaciones donde la estética desempeña una función importante. Una de las aplicaciones de las re­sinas acetálicas es el campo de la Prótesis Parcial Removible, cuan­do queremos sustituir los retene­dores vestibulares convencionales (metálicos) por retenedores más es­téticos. Otra posible aplicación puede ser la...

  8. Proceedings: Condenser technology conference

    International Nuclear Information System (INIS)

    Tsou, J.L.; Mussalli, Y.G.

    1991-08-01

    Seam surface condenser and associated systems performance strongly affects availability and heat rate in nuclear and fossil power plants. Thirty-six papers presented at a 1990 conference discuss research results, industry experience, and case histories of condenser problems and solutions. This report contains papers on life extension, performance improvement, corrosion and failure analysis, fouling prevention, and recommendation for future R ampersand D. The information represents recent work on condenser problems and solutions to improve the procurement, operation, and maintenance functions of power plant personnel. Several key points follow: A nuclear and a fossil power plant report show that replacing titanium tube bundles improves condenser availability and performance. One paper reports 10 years of experience with enhanced heat transfer tubes in utility condensers. The newly developed enhanced condenser tubes could further improve condensing heat transfer. A new resistance summation method improves the accuracy of condenser performance prediction, especially for stainless steel and titanium tubed condensers. Several papers describe improved condenser fouling monitoring techniques, including a review of zebra mussel issues

  9. Condensate cleaning systems

    International Nuclear Information System (INIS)

    Yamamoto, Michiyoshi; Oosumi, Katsumi; Takashima, Yoshie; Mitani, Shinji.

    1982-01-01

    Purpose: To decrease the frequency for the backwash and regeneration operations due to the increase in the differential pressure resulted from claddings captured in a mixed floor type desalter, and decrease the amount of radioactive liquid wastes of claddings from the condensate systems by removing claddings with electromagnetic filters. Constitution: In an existent plant, a valves is disposed between a condensate pump and a mixed floor type desalter. A pipeway is branched from a condensate pipe between the condensate pipe and the valve, through which condensates are transferred by a pump to an electromagnetic filter such as of a high gradient type electromagntic filter to remove claddings, then returned to a condensate pipe between the valve and the mixed floor type desalter and, thereafter, are removed with ionic components in the mixed floor type desalter and fed to the reactor. (Yoshino, Y.)

  10. Purification method for condensate

    International Nuclear Information System (INIS)

    Shimoda, Akiyoshi.

    1996-01-01

    Condensates generated in secondary coolant circuits of a PWR type reactor are filtered using a hollow thread separation membranes comprising aromatic polyether ketone. Preferably, condensates after passing through a turbine are filtered at a place between a condensator and a steam generator at high temperature as close as a temperature of the steam generator. As the hollow thread membrane, partially crystalline membrane comprising aromatic polyether ketone is used. When it is used at high temperature, the crystallinity is preferably not less than 15wt%. Since a hollow thread membrane comprising the aromatic polyether ketone of excellent heat resistance is used, it can filter and purify the condensates at not lower than 70degC. Accordingly, impurities such as colloidal iron can be removed from the condensates, and the precipitation of cruds in the condensates to a steam generator and a turbine can be suppressed. (I.N.)

  11. Atenuação da intensidade de luz e profundidade de polimerização de resinas compostas

    OpenAIRE

    Werlang, Jean Felipe Garlet; Dalfovo, Ricardo João; Neiva, Ivana Froede; Obici, Andresa Carla

    2016-01-01

    Objetivo: Avaliar a atenuação da luz através de diferentes espessuras de resina composta e a profundidade de polimerização. Materiais e Métodos: Foram utilizadas as resinas Opallis e Llis de esmalte (E) e de dentina (D), na cor A3. Para atenuação da luz foram empregadas matrizes metálicas (6,0mm de diâmetro e espessuras de 0,5, 1,0, 1,5 e 2,0mm), as quais foram posicionadas na janela de leitura do radiômetro e a intensidade de luz medida antes e após a interposição do material. A profundidade...

  12. Influência de três modos de fotopolimerização sobre a microdureza de três resinas compostas

    Directory of Open Access Journals (Sweden)

    Andréa Cristina Schneider

    2016-01-01

    Full Text Available Resumo A adequada fotopolimerização das resinas compostas é fundamental para obtenção de uma boa dureza capaz de resistir aos esforços mastigatórios. Assim, o objetivo deste estudo foi avaliar a influência das técnicas de fotopolimerização - Convencional (CONV, Soft-start (SS e Pulso atrasado (PA na microdureza Knoop de três resinas compostas. Para a confecção dos corpos-de-prova foram utilizadas as resinas compostas Filtek Z350 (3M ESPE, Empress Direct (IvoclarVivadent e P90 (3M ESPE. Foram obtidos nove grupos experimentais em função da técnica de polimerização e resina composta. Vinte e quatro horas após a fotopolimerização foi realizado o teste de microdureza Knoop nas superfícies de base e topo de cada corpo-de-prova. Assim, os valores obtidos foram submetidos ao teste de Kruskall Wallis, seguido do teste de Dunn, p < 0,05. A eficácia da polimerização na superfície de topo das resinas compostas testadas não foi afetada pelos diferentes modos de polimerização. A resina composta Empress Direct apresentou os mais baixos valores de dureza para todos os modos de polimerização quando comparada às demais resinas compostas avaliadas.

  13. Systematic text condensation

    DEFF Research Database (Denmark)

    Malterud, Kirsti

    2012-01-01

    To present background, principles, and procedures for a strategy for qualitative analysis called systematic text condensation and discuss this approach compared with related strategies.......To present background, principles, and procedures for a strategy for qualitative analysis called systematic text condensation and discuss this approach compared with related strategies....

  14. Chromosome condensation and segmentation

    International Nuclear Information System (INIS)

    Viegas-Pequignot, E.M.

    1981-01-01

    Some aspects of chromosome condensation in mammalians -humans especially- were studied by means of cytogenetic techniques of chromosome banding. Two further approaches were adopted: a study of normal condensation as early as prophase, and an analysis of chromosome segmentation induced by physical (temperature and γ-rays) or chemical agents (base analogues, antibiotics, ...) in order to show out the factors liable to affect condensation. Here 'segmentation' means an abnormal chromosome condensation appearing systematically and being reproducible. The study of normal condensation was made possible by the development of a technique based on cell synchronization by thymidine and giving prophasic and prometaphasic cells. Besides, the possibility of inducing R-banding segmentations on these cells by BrdU (5-bromodeoxyuridine) allowed a much finer analysis of karyotypes. Another technique was developed using 5-ACR (5-azacytidine), it allowed to induce a segmentation similar to the one obtained using BrdU and identify heterochromatic areas rich in G-C bases pairs [fr

  15. Condensation in complex geometries

    International Nuclear Information System (INIS)

    Lauro, F.

    1975-01-01

    A mathematical evaluation of the condensation exchange coefficient can only succeds for well specified cases: small upright or inclined plates, horizontal tubes, small height vertical tubes. Among the main hypotheses accounted for this mathematical development in the case of the condensate, a laminar flow and uniform surface temperature are always considered. In practice certain shapes of surfaces significantly increase the heat transfer during the vapor condensation on a surface wet by the condensate. Such surfaces are rough surfaces such as the condensate is submitted to surface tension effects, negligeable for plane or large curvature surfaces, and the nature of the material may play an important role (temperature gradients). Results from tests on tubes with special shapes, performed in France or out of France, are given [fr

  16. O Uso de Resina de Poliéster em Trabalho de Campo para Recobrir Espécimes Fragmentados

    Directory of Open Access Journals (Sweden)

    Helder de Paula

    2005-01-01

    Full Text Available Freqüentemente, fósseis de vertebrados são encontrados como partes de esqueletos erodidos superficialmente. Em vários casos, os ossos estão demasiadamente danificados para suportar os estresses decorrentes das etapas de coleta e transporte. Não é incomum o fato de fósseis nesta situação serem deixados no campo ou mesmo serem perdidos devido a sua fragilidade. Aqui, descrevemos um simples procedimento que pode ser utilizado no campo para recobrir fósseis danificados. Aplicamos este procedimento com grande sucesso no fêmur de um dinossauro saurópoda coletado no sítio Confusão (município de Tesouro, uma localidade recentemente descoberta no estado do Mato Grosso. O material é preservado numa matriz conglometrática correlacionável com o Grupo Bauru. O fêmur (MN 6813-V possui aproximadamente 110 cm de largura e tinha a metade distal parcialmente exposta devido as periódicas enchentes do rio Confusão. Ele possui uma Saliên cia lateral bem desenvolvida a qual é considerada como uma característica titanossauriforme. A porção distal, incluindo a articulação, estava preservada principalmente como uma impressão na rocha, juntamente com alguns fragmentos da parte mais cortical do osso. Esta porção do fêmur estava demasiadamente friável para ser coletada como uma peça única. Após uma limpeza geral da superficie, recobrimos as porções mais frágeis da parte distal do fêmur (incluindo as impressões com diversas camadas finas de resina de poliéster que foram gentilmente aplicadas com um pincel. Usamos 0,75% de metil etil cetona (MEK como catalisador para a resina de poliéster e esperamos até que cada camada de resina secasse lentamente. Na seqüência, uma camada mais espessa de resina com gaze foi utilizada para fazer esta região mais resistente e forte o bastante para se manter por si só. As demais partes do processo de coleta seguiram os procedimentos tradicionais incluindo o uso de uma jaqueta de gesso. Entre os

  17. Implante de um floculado de resina de mamona em alvéolo dental de rato

    Directory of Open Access Journals (Sweden)

    CALIXTO Romeu Felipe Elias

    2001-01-01

    Full Text Available Os objetivos do presente trabalho foram: 1 testar a biocompatibilidade de uma resina natural, derivada do óleo de mamona, implantada na cavidade de extração dental de ratos, e 2 estudar a possível interferência do material na cronologia do reparo alveolar. O material (AUG-EX, Poliquil Araraquara Polímeros Químicos Ltda., Araraquara - SP foi implantado no alvéolo imediatamente após a extração do incisivo superior direito e os ratos foram sacrificados de 1 a 6 semanas após a extração ou extração + implante. As hemimaxilas foram descalcificadas e processadas para inclusão em parafina e obtenção de cortes semi-seriados, corados com hematoxilina-eosina. Os flocos da resina, de forma irregular e tamanho variável, localizaram-se entre os terços alveolares médio e cervical, inicialmente circundados por tecido de granulação e a seguir por quantidade progressivamente maior de tecido ósseo, no geral com a presença de um tecido conjuntivo interposto, mas em algumas áreas estabelecendo aparente osseointegração direta. Não houve persistência da reação inflamatória, mas observou-se pequena quantidade de células gigantes aderidas à superfície do material, em todos os períodos. A análise histométrica (contagem diferencial de pontos do terço apical mostrou um atraso de 13% a 20% no reparo alveolar dos ratos implantados, com menor neoformação óssea associada a maiores volumes percentuais de tecido conjuntivo e de remanescentes do coágulo sangüíneo.

  18. Sedimentary condensation and authigenesis

    Science.gov (United States)

    Föllmi, Karl

    2016-04-01

    Most marine authigenic minerals form in sediments, which are subjected to condensation. Condensation processes lead to the formation of well individualized, extremely thin ( 100ky), and which experienced authigenesis and the precipitation of glaucony, verdine, phosphate, iron and manganese oxyhydroxides, iron sulfide, carbonate and/or silica. They usually show complex internal stratigraphies, which result from an interplay of sediment accumulation, halts in sedimentation, sediment winnowing, erosion, reworking and bypass. They may include amalgamated faunas of different origin and age. Hardgrounds may be part of condensed beds and may embody strongly condensed beds by themselves. Sedimentary condensation is the result of a hydrodynamically active depositional regime, in which sediment accumulation, winnowing, erosion, reworking and bypass are processes, which alternate as a function of changes in the location and intensity of currents, and/or as the result of episodic high-energy events engendered by storms and gravity flow. Sedimentary condensation has been and still is a widespread phenomenon in past and present-day oceans. The present-day distribution of glaucony and verdine-rich sediments on shelves and upper slopes, phosphate-rich sediments and phosphorite on outer shelves and upper slopes, ferromanganese crusts on slopes, seamounts and submarine plateaus, and ferromanganese nodules on abyssal seafloors is a good indication of the importance of condensation processes today. In the past, we may add the occurrence of oolitic ironstone, carbonate hardgrounds, and eventually also silica layers in banded iron formations as indicators of the importance of condensation processes. Besides their economic value, condensed sediments are useful both as a carrier of geochemical proxies of paleoceanographic and paleoenvironmental change, as well as the product of episodes of paleoceanographic and paleoenvironmental change themselves.

  19. Avaliação in vitro da microinfiltração em cavidades classe II de molares decíduos, restaurados com resina composta auto e fotopolimerizável

    Directory of Open Access Journals (Sweden)

    CAVALCANTI Alessandro Leite

    1999-01-01

    Full Text Available Estudou-se a microinfiltração marginal presente na interface da parede gengival de cavidades classe II em molares decíduos, restaurados com resina composta (auto e fotopolimerizável, através da penetração de uma solução corante. Os preparos cavitários apresentavam a parede gengival em esmalte e foram restaurados segundo 4 diferentes técnicas: 1 resina composta fotopolimerizável; 2 resina composta autopolimerizável; 3 resina composta auto e fotopolimerizável; e 4 ionômero de vidro/resina composta. Após a análise estatística dos resultados, concluiu-se que todos os grupos apresentaram microinfiltração em graus variados; todavia, os grupos 2, 3 e 4 apresentaram os menores graus de infiltração.

  20. Physics of condensed matter

    CERN Document Server

    Misra, Prasanta K

    2012-01-01

    Physics of Condensed Matter is designed for a two-semester graduate course on condensed matter physics for students in physics and materials science. While the book offers fundamental ideas and topic areas of condensed matter physics, it also includes many recent topics of interest on which graduate students may choose to do further research. The text can also be used as a one-semester course for advanced undergraduate majors in physics, materials science, solid state chemistry, and electrical engineering, because it offers a breadth of topics applicable to these majors. The book be

  1. Condensation in Microchannels

    National Research Council Canada - National Science Library

    Ameel, Timothy

    1999-01-01

    .... Evaporators and condensers for meso-scale energy systems will most likely be constructed of microchannels due to the microfabrication constraints that limit most structures to two-dimensional planar geometries...

  2. Biochemical analysis of the Hormoconis resinae fungal mycelium in the corrosion of aeronautical aluminium alloys

    International Nuclear Information System (INIS)

    Araya, R.; Bobadilla, C.; Vera, R.; Rosales, B. M.

    2007-01-01

    Biochemical analyses of the Hormoconis resinae fungal mycelium would explain behaviour differences of corrosive and non-corrosive strains of Al and its aeronautical alloys. In previous works its aggressiveness had been studied through SEM-EDX surface analysis, electrochemical techniques and immersion testing. In this paper separation of the proteins of the mycelium produced by a non-corrosive strain and its culture along three generations was performed. cultures were prepared in batch in the presence and absence of pure Al and AA 2024, AA 7005 and AA 7075 alloys. The mycelia grown throughout the three generations increasingly recovered usual characteristics at the third replication, included their corrosiveness on Al and its alloys previously shown by all out strains. Among the bio-molecule fractions isolated and analysed during this preliminary study only the proteins revealed changes with the generation grown. When this fungal strain was cultured in the presence of alloy metal sheets electrophoresis of the protean fraction was correlative with the distinct mycelia behaviour observed, including corrosiveness on Al and its alloys. (Author) 30 refs

  3. Boilers, evaporators, and condensers

    International Nuclear Information System (INIS)

    Kakac, S.

    1991-01-01

    This book reports on the boilers, evaporators and condensers that are used in power plants including nuclear power plants. Topics included are forced convection for single-phase side heat exchangers, heat exchanger fouling, industrial heat exchanger design, fossil-fuel-fired boilers, once through boilers, thermodynamic designs of fossil fuel-first boilers, evaporators and condensers in refrigeration and air conditioning systems (with respect to reducing CFC's) and nuclear steam generators

  4. Molecular equilibrium with condensation

    International Nuclear Information System (INIS)

    Sharp, C.M.; Huebner, W.F.

    1990-01-01

    Minimization of the Gibbs energy of formation for species of chemical elements and compounds in their gas and condensed phases determines their relative abundances in a mixture in chemical equilibrium. The procedure is more general and more powerful than previous abundance determinations in multiphase astrophysical mixtures. Some results for astrophysical equations of state are presented, and the effects of condensation on opacity are briefly indicated. 18 refs

  5. SLAC synchronous condenser

    International Nuclear Information System (INIS)

    Corvin, C.

    1995-06-01

    A synchronous condenser is a synchronous machine that generates reactive power that leads real power by 90 degrees in phase. The leading reactive power generated by the condenser offsets or cancels the normal lagging reactive power consumed by inductive and nonlinear loads at the accelerator complex. The quality of SLAC's utility power is improved with the addition of the condenser. The inertia of the condenser's 35,000 pound rotor damps and smoothes voltage excursions on two 12 kilovolt master substation buses, improving voltage regulation site wide. The condenser absorbs high frequency transients and noise in effect ''scrubbing'' the electric system power at its primary distribution source. In addition, the condenser produces a substantial savings in power costs. Federal and investor owned utilities that supply electric power to SLAC levy a monthly penalty for lagging reactive power delivered to the site. For the 1993 fiscal year this totaled over $285,000 in added costs for the year. By generating leading reactive power on site, thereby reducing total lagging reactive power requirements, a substantial savings in electric utility bills is achieved. Actual savings of $150,000 or more a year are possible depending on experimental operations

  6. Evaluación del efecto citotóxico de una resina dental a base de siloranos sobre fibroblastos L929

    Directory of Open Access Journals (Sweden)

    Milena Guerrero F

    2016-04-01

    Full Text Available Introducción: Las resinas dentales basadas en siloranos, son el resultado de la unión química de siloxanos y oxiranos. Dentro del proceso de evolución de las resinas, se han modificado sus formulaciones para optimizar sus propiedades físicas, mecánicas y estéticas. Sin embargo, aún presentan problemas como la contracción de polimerización, problemas alérgicos y toxicológicos. Objetivo: Determinar el potencial efecto citotóxico de las resinas a base de siloranos sobre la viabilidad celular en un cultivo de fibroblastos de la línea L929. Metodología: Se estudió la exposición de fibroblastos de ratón L929 a resinas dentales a base de siloranos Filtek p90 y metacrilatos Filtek p60 en tres tiempos de fotocurado durante 6 días. Se evaluó el efecto sobre la viabilidad celular mediante pruebas de exclusión vital, micrografías electrónicas y composición elemental de superficie (Mg, Na, K y Ca por ESEM/EDAX. Resultados: La resina Filtek p90 mostró un mayor efecto citotóxico a tiempos de fotocurado prolongados (20 segundos o más respecto a la resina Filtek p60. El efecto resultó más marcado para 20 segundos de fotocurado, ya que las concentraciones de Ca y K en la superficie celular fueron las más afectadas. Conclusiones: La resina dental Filtek p90 ejerce un efecto citotóxico relativamente bajo sobre las células de fibroblastos L929 (p <0.01. Su uso en la práctica odontológica se puede considerar bioseguro, pero un tiempo de fotocurado prolongado con la resina dental a base de siloranos puede afectar significativamente la viabilidad de los tejidos dentales

  7. Análise por imagem digital dos níveis de cinza de fibras de reforço associadas a uma resina composta = Digital image analysis of the gray levels of reinforcement fibers associated with composite resin

    Directory of Open Access Journals (Sweden)

    Mussatto, Cristiane Maria Boniatti

    2005-01-01

    Full Text Available Mensurar a densidade óptica das fibras de reforço Connect, Ribbond e Interlig incluídas em resina composta Filtek Z250, no sistema DenOptix. Materiais e método: Foram confeccionados 10 blocos de resina composta associadas a cada tipo de fibra e dois blocos de resina Z250 pura (controle não-reforçado, totalizando 32 corpos-de-prova. Foram obtidas 3 radiografias digitais de cada corpo-de-prova, sobre uma placa óptica do sistema DenOptix, para cada posição: (A face lateral da fibra exposta aos raios -X; (B face tramada da fibra exposta aos raios-X. Em cada uma foram realizadas 3 leituras ópticas dos níveis de cinza em cada corpo-de-prova, em pontos aleatórios, sendo obtida uma média. Os valores médios dos níveis de cinza foram analisados pelo teste t de Student, ANOVA e teste de Tukey, ao nível de significância de 1%. Resultados e conclusões: Com relação à associação da resina + fibra na posição (A, observou-se a maior média de níveis de cinza para a resina pura, seguido por resina + Connect, resina + Interlig (que não diferiram entre si, e resina + Ribbond. Com relação à associação da resina + fibra na posição (B, observou-se que a resina pura apresentou maior média, seguida por resina + Connect, resina + Interlig e resina + Ribbond, sendo que as duas últimas não foram diferentes entre si. Os resultados sugerem que os níveis de cinza variaram em função do tipo de fibra de reforço e da posição na radiografia

  8. Caracterización estructural y electroquímica de una membrana compuesta de TiO2 y de su soporte poroso basado en arcillas naturales

    Directory of Open Access Journals (Sweden)

    Rodríguez-Castellón, E.

    2004-02-01

    Full Text Available The manufacture and characterisation of an inorganic composite membrane (MC consisting of a thin layer of TiO2 (atanase phasedeposited on a porous support (SP obtained from natural clay has been carried out. Chemical and structural characterisations have been mainly made by X ray photoelectron spectroscopy and electronic microphotographs. An electrochemical characterisation of both MC and SP membranes has also been carried out by measuring membrane potential and electrical impedance with the membranes in contact with NaCl solutions at different concentrations. The results allow an estimation of structural parameters for the TiO2 sub-layer and they also show the weak anionic character of this sublayer with a cationic permeselectivity around 10%.Se ha fabricado y caracterizado una membrana inorgánica compuesta (MC consistente en una capa delgada de TiO2 (fase atanasa sobre un soporte poroso (SP obtenido a partir de arcillas naturales. La caracterización química y estructural se ha realizado, principalmente, a partir de los resultados de XPS y de microscopía electrónica de barrido. También se ha realizado una caracterización electroquímica de ambas membranas (MC y SP en contacto con disoluciones de NaCl a distintas concentraciones mediante medidas de espectrocopía de impedancias y potencial de membrana. Los resultados han permitido estimar parámetros geométricos de la capa de TiO2 y poner de manifiesto un carácter débilmente aniónico, con una permeselectividad catiónica del 10%.

  9. Estudo do comportamento fotofísico de prepregs de fibra de vidro e resina fenólica.

    OpenAIRE

    Rogério da Silva Rosa

    2007-01-01

    O objetivo desse trabalho é a aplicação da Espectroscopia de Luminescência em modo estacionário para o estudo do processo de cura de pré-impregnados (prepregs) de fibra de vidro e resina fenólica, tratadas termicamente em três diferentes temperaturas 90, 120 e 150 C. O processo de cura dos prepregs também foi monitorado por Espectroscopia de absorção na região do Infravermelho com transformada de Fourier (FT-IR). Os espectros de luminescência dos prepregs mostram mudanças significativas atrib...

  10. Intensidade de fluorescência em resina composta: influência do polimento superficial e dos meios de armazenagem

    Directory of Open Access Journals (Sweden)

    Ângela Dalla Nora

    Full Text Available INTRODUÇÃO: A resina composta é um material versátil em Odontologia Estética, principalmente por suas propriedades ópticas, dentre as quais a fluorescência. Poucos são os estudos que avaliaram esta propriedade e a comparação dos resultados encontrados torna-se difícil em função da inexistência de padronização nas metodologias na confecção e na armazenagem dos corpos de prova. OBJETIVO: Verificar a influência do polimento superficial e do meio de armazenagem, em estudos in vitro, em que se avalia a propriedade óptica de fluorescência em resinas compostas. MATERIAL E MÉTODO: Foram preparados 70 corpos de prova circulares (10 mm × 2 mm com resina composta microhíbrida (Opallis,- A2E - FGM. Os meios de armazenagem foram: água deionizada, água da torneira e saliva artificial. Os protocolos de polimento superficial, realizados em politriz após a obtenção dos corpos de prova, utilizaram lixas de granulações 600, 1200 e 2500. Os valores de intensidade de fluorescência foram avaliados através do espectrofotômetro Cary Eclipse, após 1, 7 e 21 dias. RESULTADO: Não houve diferença estatisticamente significativa na Intensidade de Fluorescência entre os grupos submetidos aos diferentes protocolos de polimento. Quanto aos meios de armazenagem, a partir do sétimo dia, a variação de fluorescência foi significativamente maior em água da torneira e deionizada, quando comparada à variação observada em saliva artificial, resultado que se manteve após 21 dias. CONCLUSÃO: O protocolo de polimento superficial não promoveu alterações significativas na fluorescência da resina composta avaliada. Quanto ao meio de armazenagem, a intensidade de fluorescência foi menos afetada quando em saliva artificial.

  11. Utilização de resinas de troca-iônica em efluentes de galvanoplastia.

    OpenAIRE

    Josiane Costa Riani

    2008-01-01

    A crescente industrialização acompanhada do uso de metais pesados nos processos industriais nas últimas décadas resultou num aumento da contaminação do meio ambiente, principalmente em ambientes aquáticos. Assim, sendo a água um recurso natural de suma importância para a vida, métodos de tratamento de efluentes tornam-se indispensáveis para empresas geradoras de efluentes. O objetivo desse trabalho é a utilização de um sistema de troca iônica constituído por micro-colunas de resinas catiônica...

  12. Avaliação das propriedades elétricas de barras estatóricas fabricadas com resina do tipo éter diglicidílico do bisfenol F (DGEBF contendo nanopartículas de silica

    Directory of Open Access Journals (Sweden)

    Rafael Novaes da Conceição

    Full Text Available Resumo O presente trabalho visa apresentar resultados da aplicação de uma resina epóxi bisfenólica (DGEBF à base de nanopartículas de sílica (RN e comparar suas propriedades com a resina convencional de referência epóxi bisfenólica (DGEBA (RE, atualmente utilizada. Neste sentido fabricaram-se protótipos de barras estatórica, destinadas a hidrogeradores, através do sistema VPI (Vácuo-Pressão-Impregnação e avaliaram-se as propriedades elétricas pelas técnicas de fator de dissipação e envelhecimento acelerado. Dentre os resultados para as resinas observou-se que: (i o fator de dissipação e de envelhecimento são praticamente os mesmos para ambas as resinas; (ii o valor de tip-up resultaram em 0,014% para RE e 0,020% para a resina RN e (iii a estimativa do tempo de vida útil esta em cerca de 40 anos, o que é aplicável para a maioria das aplicações industriais. Neste sentido sugere-se que a resina RN pode ser uma alternativa a resina RE, com um desempenho elétrico equivalente.

  13. CONDENSATION OF WATER VAPOR IN A VERTICAL TUBE CONDENSER

    Directory of Open Access Journals (Sweden)

    Jan Havlík

    2015-10-01

    Full Text Available This paper presents an analysis of heat transfer in the process of condensation of water vapor in a vertical shell-and-tube condenser. We analyze the use of the Nusselt model for calculating the condensation heat transfer coefficient (HTC inside a vertical tube and the Kern, Bell-Delaware and Stream-flow analysis methods for calculating the shell-side HTC from tubes to cooling water. These methods are experimentally verified for a specific condenser of waste process vapor containing air. The operating conditions of the condenser may be different from the assumptions adopted in the basic Nusselt theory. Modifications to the Nusselt condensation model are theoretically analyzed.

  14. Containment condensing heat transfer

    International Nuclear Information System (INIS)

    Gido, R.G.; Koestel, A.

    1983-01-01

    This report presents a mechanistic heat-transfer model that is valid for large scale containment heat sinks. The model development is based on the determination that the condensation is controlled by mass diffusion through the vapor-air boundary layer, and the application of the classic Reynolds' analogy to formulate expressions for the transfer of heat and mass based on hydrodynamic measurements of the momentum transfer. As a result, the analysis depends on the quantification of the shear stress (momentum transfer) at the interface between the condensate film and the vapor-air boundary layer. In addition, the currently used Tagami and Uchida test observations and their range of applicability are explained

  15. Condensed matter physics

    CERN Document Server

    Isihara, A

    2007-01-01

    More than a graduate text and advanced research guide on condensed matter physics, this volume is useful to plasma physicists and polymer chemists, and their students. It emphasizes applications of statistical mechanics to a variety of systems in condensed matter physics rather than theoretical derivations of the principles of statistical mechanics and techniques. Isihara addresses a dozen different subjects in separate chapters, each designed to be directly accessible and used independently of previous chapters. Topics include simple liquids, electron systems and correlations, two-dimensional

  16. Análise da Fragilidade do Core - Quando reconstruído com diferentes resinas e pinos pré-fabricados não metálicos

    OpenAIRE

    Ávilal, Gisseli Bertozzi; Dias, Sérgio Cândido; Ribeiro, José Carlos Rabelo; Gomes, Priscila Nogueira; Moysés, Marcos Ribeiro

    2016-01-01

    Para realização deste estudo vinte condutos artificiais foram construídos em blocos formados por esmalte e dentina, a partir de dentes bovinos. Dez pinos de fibra de vidro e dez de fibra de carbono foram cimentados nos condutos com cimento resinoso C&B. Empregou-se matriz de policarbonato para confecção do core em resina composta, perfazendo quatro grupos: Grupo (1) pino de fibra de vidro e core com resina composta Charisma; Grupo (2) pino de fibra de carbono e core com resina composta Charis...

  17. PROPRIEDADES FÍSICAS E MECÂNICAS DE PAINÉIS MDF DE DIFERENTES MASSAS ESPECÍFICAS E TEORES DE RESINA

    Directory of Open Access Journals (Sweden)

    Jackson Roberto Eleotério

    2000-08-01

    Full Text Available Painéis MDF foram preparados, em escala laboratorial, com base em fibras de Pinus spp. com diferentes teores de resina (6, 8, 10, 12 e 14% e massas específicas (600 a 800 kg/m3 com o objetivo de avaliar suas propriedades físicas e mecânicas. Os efeitos da massa específica e do teor de resina, bem como sua interação foram avaliados tendo como base as propriedades físicas e mecânicas dos painéis MDF. As propriedades mecânicas avaliadas foram módulo de elasticidade e de ruptura e adesão interna, enquanto as propriedades físicas foram absorção de água e inchamento em espessura. Todas as variáveis se relacionaram significativamente com os fatores massa específica e teor de resina e a interação foi significativa a 1% apenas no inchamento em espessura. Foram propostos modelos para avaliar as propriedades físicas e mecânicas em razão da massa específica e do teor de resina.

  18. Bioactivity-Guided Fractionation of the Traditional Chinese Medicine Resina Draconis Reveals Loureirin B as a PAI-1 Inhibitor

    Directory of Open Access Journals (Sweden)

    Yu Jiang

    2017-01-01

    Full Text Available Thrombotic diseases have become a global burden due to morbidity, mortality, and disability. Traditional Chinese medicine has been proven effective in removing blood stasis and promoting blood circulation, but the exact mechanisms remain unclear. Plasminogen activator inhibitor-1 (PAI-1 is a natural inhibitor of tissue-type and urokinase-type plasminogen activators. In this study, we screened four fractions of Resina Draconis (a traditional Chinese medicine extract for PAI-1 inhibitory activity. Bioactivity-guided purification and chromogenic substrate-based assay led to the identification of loureirin B as the major PAI-1 inhibitor, with an IC50 value of 26.10 μM. SDS-PAGE analysis showed that formation of the PAI-1/uPA complex was inhibited by loureirin B, and the inhibitory effect of loureirin B on PAI-1 was also confirmed by clot lysis assay. In vivo studies showed that loureirin B significantly prolonged the tail bleeding time and reduced the weight and size of arterial thrombus, reduced hydroxyproline level, and partly cured liver fibrosis in mice. Taken together, the results revealed loureirin B as a PAI-1 inhibitor, adding a new pharmacological target for loureirin B and uncovering a novel mechanism underlying the antithrombotic property of Resina Draconis, which might be useful in the treatment of cardiovascular diseases such as thrombosis and fibrosis.

  19. Avaliação das características da resina epóxi com diferentes aditivos desaerantes

    Directory of Open Access Journals (Sweden)

    Alexsandro Oliveira

    2015-04-01

    Full Text Available Este trabalho tem por objetivo a busca por técnicas alternativas para diminuir a incidência de vazios em resinas poliméricas e, por consequência, em materiais compósitos. Foram produzidas formulações diferentes utilizando resina epóxi à base de éter diglicidílico do Bisfenol A, endurecedor de poliamina alifática com e sem a adição de diferentes aditivos desaerantes a base de éteres e ésteres modificados. As formulações produzidas foram submetidas a condições extremas de agitação e processamento, sendo posteriormente avaliadas quanto a incidência de bolhas e vazios, densidade, propriedades mecânicas, morfológicas e térmicas. Os resultados foram bastante positivos quanto à diminuição da quantidade e do tamanho de poros pela utilização de técnicas de desgaseificação a vácuo e pelo uso de aditivos desaerantes.

  20. Simple Simulations of DNA Condensation

    Energy Technology Data Exchange (ETDEWEB)

    STEVENS,MARK J.

    2000-07-12

    Molecular dynamics simulations of a simple, bead-spring model of semiflexible polyelectrolytes such as DNA are performed. All charges are explicitly treated. Starting from extended, noncondensed conformations, condensed structures form in the simulations with tetravalent or trivalent counterions. No condensates form or are stable for divalent counterions. The mechanism by which condensates form is described. Briefly, condensation occurs because electrostatic interactions dominate entropy, and the favored Coulombic structure is a charge ordered state. Condensation is a generic phenomena and occurs for a variety of polyelectrolyte parameters. Toroids and rods are the condensate structures. Toroids form preferentially when the molecular stiffness is sufficiently strong.

  1. Vapor condensation device

    International Nuclear Information System (INIS)

    Sakurai, Manabu; Hirayama, Fumio; Kurosawa, Setsumi; Yoshikawa, Jun; Hosaka, Seiichi.

    1992-01-01

    The present invention enables to separate and remove 14 C as CO 3 - ions without condensation in a vapor condensation can of a nuclear facility. That is, the vapor condensation device of the nuclear facility comprises (1) a spray pipe for spraying an acidic aqueous solution to the evaporation surface of an evaporation section, (2) a spray pump for sending the acidic aqueous solution to the spray pipe, (3) a tank for storing the acidic aqueous solution, (4) a pH sensor for detecting pH of the evaporation section, (5) a pH control section for controlling the spray pump, depending on the result of the detection of the pH sensor. With such a constitution, the pH of liquid wastes on the vaporization surface is controlled to 7 by spraying an aqueous solution of dilute sulfuric acid to the evaporation surface, thereby enabling to increase the transfer rate of 14 C to condensates to 60 to 70%. If 14 C is separated and removed as a CO 2 gas from the evaporation surface, the pH of the liquid wastes returns to the alkaline range of 9 to 10 and the liquid wastes are returned to a heating section. The amount of spraying the aqueous solution of dilute sulfuric acid can be controlled till the pH is reduced to 5. (I.S.)

  2. Condensed matter physics

    International Nuclear Information System (INIS)

    Anon.

    1985-01-01

    The condensed matter physics research in the Physics Department of Risoe National Laboratory is predominantly experimental utilising diffraction of neutrons and x-rays. The research topics range from studies of structure, excitations and phase transitions in model systems to studies of ion transport, texture and recrystallization kinetics with a more applied nature. (author)

  3. Bose-Einstein Condensation

    Indian Academy of Sciences (India)

    absolute zero. These ideas had ... Everybody is talking about Bose-Einstein condensation. This discovery ... needed if we want to find the probability distribution of the x- ... Boltzmann took two approaches to the problem, both of them deep and ...

  4. Condensed matter physics

    International Nuclear Information System (INIS)

    1990-01-01

    This is a summary of condensed matter physics in Brazil. It discusses as well, the perspectives and financing evolved in this research area for the next decade. It is specially concerned with semiconductors, magnetic materials, superconductivity, polymers, glasses, crystals ceramics, statistical physics, magnetic resonance and Moessbauer spectroscopy. (A.C.A.S.)

  5. Preventing freezing of condensate inside tubes of air cooled condenser

    International Nuclear Information System (INIS)

    Joo, Jeong A; Hwang, In Hwan; Lee, Dong Hwan; Cho, Young Il

    2012-01-01

    An air cooled condenser is a device that is used for converting steam into condensate by using ambient air. The air cooled condenser is prone to suffer from a serious explosion when the condensate inside the tubes of a heat exchanger is frozen; in particular, tubes can break during winter. This is primarily due to the structural problem of the tube outlet of an existing conventional air cooled condenser system, which causes the backflow of residual steam and noncondensable gases. To solve the backflow problem in such condensers, such a system was simulated and a new system was designed and evaluated in this study. The experimental results using the simulated condenser showed the occurrence of freezing because of the backflow inside the tube. On the other hand, no backflow and freezing occurred in the advanced new condenser, and efficient heat exchange occurred

  6. Elaboración de una pasta de harina compuesta utilizando sémola e hidrolizado de germen desgrasado de maíz (Zea mays L.

    Directory of Open Access Journals (Sweden)

    Eumelia Gómez

    2011-01-01

    Full Text Available El germen desgrasado de maíz subproducto de la extracción del aceite, presenta niveles altos de carbohidratos, proteína, fibra y palatabilidad poco agradable, que mejora al hidrolizarlo, aumentándose la disponibilidad de sus componentes, para obtener un ingrediente potencial en la preparación de alimentos. El objetivo del trabajo fue utilizar el hidrolizado para sustituir parcialmente la sémola de trigo durum, y obtener una harina compuesta para elaborar una pasta larga, nutritiva y aceptable sensorialmente. El germen desgrasado hidrolizado enzimáticamente, se deshidrató por atomización y se elaboraron tres formulaciones sustituyendo la sémola de trigo durum por el hidrolizado en 10 %, 15 % y 20 %. Se midieron parámetros de cocción, evaluaciones físicas, químicas, microbiológicas, nutricionales y sensoriales, utilizando metodologías oficiales nacionales e internacionales. Con la sustitución disminuyeron el tiempo de cocción, el volumen y los sólidos disueltos. Los atributos evaluados olor, sabor y color señalaron que la mejor pasta fue la sustituida en 10 % (p ≤ 0,05. Los valores de proteína 12,8 % y de carbohidratos 84,10 %, fueron semejantes a la pasta de sémola de trigo durum. Los niveles de fósforo, hierro y magnesio (400 mg/100 g, 3,49 mg/100 g, 118,47 mg/100 g y el aporte energético (394 kcal/100 g fueron mayores. La estabilidad microbiológica indicó que el producto sustituido con 10 %, se mantiene apto para el consumo durante 2 meses. Se concluye que es factible el uso del hidrolizado en un 10 % de sustitución en la elaboración de pasta larga, con alta aceptabilidad.

  7. Diseño de conexiones mecánicas tipo canal en vigas compuestas bajo fuego//Design of channel mechanical connections in composite beam in

    Directory of Open Access Journals (Sweden)

    Yisel Larrua‐Pardo

    2015-01-01

    Full Text Available En este trabajo se propusieron dos métodos, uno simplificado y otro gráfico alternativo para el diseño de la conexión mecánica tipo canal en vigas compuestas de hormigón y acero en situación de incendio, a partir del estudio de su comportamiento. Se utilizó como herramienta la modelación numérica. El método simplificado desarrollado considera temperaturas definidas a través de la modelación térmica del ensayo push-out en situación de incendio y es coherente con las expresiones de diseño de las conexiones mecánicas tipo canal a temperatura ambiente y la formulación existente para el diseño de las conexiones tipo perno a elevadas temperaturas. El método gráfico alternativopropuesto constituye una opción que permite obtener de una forma directa y rápida, la resistencia a elevadas temperaturas de la conexión mecánica tipo canal para un tiempo de resistencia al fuego, en función de su resistencia a temperatura ambiente.Palabras claves: conexión mecánica tipo canal, método simplificado, método gráfico alternativo, modelación numérica, incendio._______________________________________________________________________________AbstractIn this paper two methods to design of channel mechanical connection are proposed, a simplified one and graphical alternative another, both using the numerical analysis for the study of the mechanical connection behavior. The developed simplified method considers temperatures defined through thethermal modelling of the push-out test in fire and it is coherent with the design expressions of the channel mechanical connections to ambient temperature, and the current formulation for the design of the stud connections al elevated temperatures. The proposed alternative graphical method constitutes an option that allows obtaining, in a direct and quick way, the resistance to elevatedtemperatures of the channel mechanical connections for a determined time of resistance to the fire, according to its

  8. Evaluación de resinas de intercambio iónico para el control del hierro en soluciones de electro-obtención de cobre

    Directory of Open Access Journals (Sweden)

    Parada, F.

    2010-08-01

    Full Text Available Two commercial resins were evaluated for the extraction of iron from a copper electrowinning solution. Both resins efficiently extract iron. TheMonophosphonic resin has a greater charge capacity than the Diphonix resin and the Diphonix resin shows faster kinetics. Experimental results of the interrupted test and tests with different particle size of resins have demonstrated that extraction kinetics is controlled by diffusion into the particle in both resins. A good agreement with Fick’s model for diffusion inside the particles confirms the proposed mechanism. Finally, temperature favors the process kinetics and its effect on the diffusion coefficient follows Arrhenius law, obtaining a value of 4,89 kcal/mol for theMonophosphonic resin and 4,94 kcal/mol for the Dphonix resin. The aforementioned values are close to typical values for the proposed diffusional control which are 6 to 10 kcal/mol.

    Se evaluaron dos resinas comerciales para la extracción del hierro desde una solución de electro-obtención de cobre. Ambas resinas extraen en forma eficiente el hierro, pero se diferencian en que la resina Monophosphonic tiene una mayor capacidad de carga que la resina Diphonix, mientras que la Diphonix muestra una cinética más rápida. Los resultados de la prueba interrumpida y de las pruebas para determinar el efecto del tamaño de partícula permiten concluir que el control más probable para la cinética de extracción es por la difusión en la partícula en ambas resinas. Un buen ajuste al modelo de Fick para difusión en la partícula confirman el tipo de control propuesto. Finalmente, la temperatura favorece la cinética del proceso de extracción y su efecto en el coeficiente de difusión sigue la ley de Arrhenius obteniendo un valor para la energía de activación de 4,89 kcal/mol para la resina Monophosphonic y 4,94 kcal/mol para la resina Diphonix. Estos valores están cercanos al valor típico para el control propuesto que es de 6 a

  9. Análise de peças anatômicas preservadas com resina de poliester para estudo em anatomia humana

    Directory of Open Access Journals (Sweden)

    Ítalo Martins de Oliveira

    Full Text Available OBJETIVO: avaliar o uso da resina de poliéster na preservação de peças anatômicas para estudo da anatomia humana. MÉTODOS: foram utilizadas 150 peças anatômicas, sendo as mesmas não fixadas (frescas, fixadas em formol a 10% e moldes vasculares de órgãos injetados com acetato de vinil e a resina de poliéster. A solução utilizada foi composta de resina de poliéster com seu diluente monômero de estireno e catalisador (peroxol. Foram obtidos, após a inclusão nesta solução, modelos em resina transparente, que permitiam a plena observação das estruturas e conservação da peça utilizada. RESULTADOS: na avaliação das peças, foi observado grau de extrema transparência, promovendo uma completa visualização das estruturas com a perfeita preservação da anatomia. A duração média para a completa finalização da inclusão foi 48 horas. Apenas 14 peças (9,3% foram inutilizadas durante o preparo. CONCLUSÃO: a resina de poliéster pode ser utilizada para a preservação de peças anatômicas para o ensino da anatomia humana, de maneira prática, estética e duradoura.

  10. Avaliação in vitro da atividade antibacteriana de um cimento odontológico à base de óleo-resina de Copaifera multijuga Hayne

    Directory of Open Access Journals (Sweden)

    Kátia Regina Felizardo Vasconcelos

    Full Text Available Um dos materiais utilizados para a adequação do meio bucal no serviço público é o cimento produzido a partir de óxido de zinco e eugenol. Entretanto, o eugenol é uma substância citotóxica que pode desencadear alguns efeitos adversos. Por essa razão, procura-se substituir o eugenol por uma substância que apresente baixa toxicidade, mantendo ou mesmo melhorando as propriedades do cimento. O óleo-resina de copaíba é um produto natural, utilizado pelas populações amazônicas e reconhecido por suas propriedades medicinais. Baseando-se nas propriedades desse óleo-resina, na ação antimicrobiana comprovada do hidróxido de cálcio e na ação anti-séptica do óxido de zinco, propôs-se formular um cimento odontológico obtido da associação do ZnO, Ca(OH2 e óleo-resina de Copaifera multijuga Hayne e avaliar sua atividade antibacteriana através do teste de diluição em meio líquido frente às cepas padrão de Streptococcus mutans (ATCC 25175 e S. sanguinis (ATCC 15300. Nesse ensaio, utilizaram-se os seguintes grupos experimentais: o cimento contendo ZnO, Ca(OH2 e óleo-resina de copaíba (G1 e cada um dos constituintes isoladamente, ZnO (G2, Ca(OH2 (G3 e óleo-resina de copaíba (G4. Todos os grupos analisados demonstraram atividade antibacteriana, o G4 apresentou os melhores resultados e o G1 mostrou-se um cimento promissor a ser utilizado em odontologia.

  11. Bose Condensate in He II

    International Nuclear Information System (INIS)

    Svensson, E.C.

    1984-01-01

    The Condensate Saga, now halfway through its fifth decade, is reviewed. The recent neutron-scattering work which has at last convincingly established that there is indeed a Bose Condensate in He II is described

  12. Maintaining steam/condensate lines

    International Nuclear Information System (INIS)

    Russum, S.A.

    1992-01-01

    Steam and condensate systems must be maintained with the same diligence as the boiler itself. Unfortunately, they often are not. The water treatment program, critical to keeping the boiler at peak efficiency and optimizing operating life, should not stop with the boiler. The program must encompass the steam and condensate system as well. A properly maintained condensate system maximizes condensate recovery, which is a cost-free energy source. The fuel needed to turn the boiler feedwater into steam has already been provided. Returning the condensate allows a significant portion of that fuel cost to be recouped. Condensate has a high heat content. Condensate is a readily available, economical feedwater source. Properly treated, it is very pure. Condensate improves feedwater quality and reduces makeup water demand and pretreatment costs. Higher quality feedwater means more reliable boiler operation

  13. Continuous condensation in nanogrooves

    Science.gov (United States)

    Malijevský, Alexandr

    2018-05-01

    We consider condensation in a capillary groove of width L and depth D , formed by walls that are completely wet (contact angle θ =0 ), which is in a contact with a gas reservoir of the chemical potential μ . On a mesoscopic level, the condensation process can be described in terms of the midpoint height ℓ of a meniscus formed at the liquid-gas interface. For macroscopically deep grooves (D →∞ ), and in the presence of long-range (dispersion) forces, the condensation corresponds to a second-order phase transition, such that ℓ ˜(μcc-μ ) -1 /4 as μ →μcc - where μc c is the chemical potential pertinent to capillary condensation in a slit pore of width L . For finite values of D , the transition becomes rounded and the groove becomes filled with liquid at a chemical potential higher than μc c with a difference of the order of D-3. For sufficiently deep grooves, the meniscus growth initially follows the power law ℓ ˜(μcc-μ ) -1 /4 , but this behavior eventually crosses over to ℓ ˜D -(μ-μc c) -1 /3 above μc c, with a gap between the two regimes shown to be δ ¯μ ˜D-3 . Right at μ =μc c , when the groove is only partially filled with liquid, the height of the meniscus scales as ℓ*˜(D3L) 1 /4 . Moreover, the chemical potential (or pressure) at which the groove is half-filled with liquid exhibits a nonmonotonic dependence on D with a maximum at D ≈3 L /2 and coincides with μc c when L ≈D . Finally, we show that condensation in finite grooves can be mapped on the condensation in capillary slits formed by two asymmetric (competing) walls a distance D apart with potential strengths depending on L . All these predictions, based on mesoscopic arguments, are confirmed by fully microscopic Rosenfeld's density functional theory with a reasonable agreement down to surprisingly small values of both L and D .

  14. Keeping condensers clean

    Energy Technology Data Exchange (ETDEWEB)

    Wicker, K.

    2006-04-15

    The humble condenser is among the biggest contributors to a steam power plant's efficiency. But although a clean condenser can provide great economic benefit, a dirty one can raise plant heat rate, resulting in large losses of generation revenue and/or unnecessarily high fuel bills. Conventional methods for cleaning fouled tubes range form chemicals to scrapers to brushes and hydro-blasters. This article compares the available options and describes how one power station, Omaha Public Power District's 600 MW North Omaha coal-fired power station, cleaned up its act. The makeup and cooling water of all its five units comes from the Missouri River. 6 figs.

  15. Condensed matter physics

    CERN Document Server

    Marder, Michael P

    2010-01-01

    This Second Edition presents an updated review of the whole field of condensed matter physics. It consolidates new and classic topics from disparate sources, teaching not only about the effective masses of electrons in semiconductor crystals and band theory, but also about quasicrystals, dynamics of phase separation, why rubber is more floppy than steel, granular materials, quantum dots, Berry phases, the quantum Hall effect, and Luttinger liquids.

  16. Condensed elementary particle matter

    International Nuclear Information System (INIS)

    Kajantie, K.

    1996-01-01

    Quark matter is a special case of condensed elementary particle matter, matter governed by the laws of particle physics. The talk discusses how far one can get in the study of particle matter by reducing the problem to computations based on the action. As an example the computation of the phase diagram of electroweak matter is presented. It is quite possible that ultimately an antireductionist attitude will prevail: experiments will reveal unpredicted phenomena not obviously reducible to the study of the action. (orig.)

  17. BWR condensate filtration studies

    International Nuclear Information System (INIS)

    Wilson, J.A.; Pasricha, A.; Rekart, T.E.

    1993-09-01

    Poor removal of particulate corrosion products (especially iron) from condensate is one of the major problems in BWR systems. The presence of activated corrosion products creates ''hot spots'' and increases piping dose rates. Also, fuel efficiency is reduced and the risk of fuel failure is increased by the deposit of corrosion products on the fuel. Because of these concerns, current EPRI guidelines call for a maximum of 2 ppb of iron in the reactor feedwater with a level of 0.5 ppb being especially desirable. It has become clear that conventional deep bed resins are incapable of meeting these levels. While installation of prefilter systems is an option, it would be more economical for plants with naked deep beds to find an improved bead resin for use in existing systems. BWR condensate filtration technologies are being tested on a condensate side stream at Hope Creek Nuclear Generating Station. After two years of testing, hollow fiber filters (HFF) and fiber matrix filters (FMF), and low crosslink cation resin, all provide acceptable results. The results are presented for pressure drop, filtration efficiency, and water quality measurements. The costs are compared for backwashable non-precoat HFF and FMF. Results are also presented for full deep bed vessel tests of the low crosslink cation resin

  18. Condensation of exciton polaritons

    International Nuclear Information System (INIS)

    Kasprzak, J.

    2006-10-01

    Because of their unique property of bringing pure quantum effects into the real world scale, phase transitions towards condensed phases - like Bose-Einstein condensation (BEC), superfluidity, and superconductivity - have always fascinated scientists. The BEC, appearing upon cooling a gas of bosons below a critical temperature, has been given a striking demonstration in dilute atomic gases of rubidium atoms at temperatures below 200 nK. By confining photons in a semiconductor micro-cavity, and strongly coupling them to electronic excitations, one may create polaritons. These bosonic quasi-particles are 10 9 times lighter than rubidium atoms, thus theoretically allowing a BEC at standard cryogenic temperatures. Here we detail a comprehensive set of experiments giving compelling evidence for a BEC of polaritons. Above a critical density, we observe massive occupation of the ground state, developing from a thermalized and saturated distribution of the polariton population at (16-20) K. We demonstrate as well the existence of a critical temperature for this transition. The spontaneous onset of a coherent state is manifested by the increase of temporal coherence, the build-up of long-range spatial coherence and the reduction of the thermal noise observed in second order coherence experiments. The marked linear polarization of the emission from the condensate is also measured. All of these findings indicate the spontaneous onset of a macroscopic quantum phase. (author)

  19. Polymorphism of Lysozyme Condensates.

    Science.gov (United States)

    Safari, Mohammad S; Byington, Michael C; Conrad, Jacinta C; Vekilov, Peter G

    2017-10-05

    Protein condensates play essential roles in physiological processes and pathological conditions. Recently discovered mesoscopic protein-rich clusters may act as crucial precursors for the nucleation of ordered protein solids, such as crystals, sickle hemoglobin polymers, and amyloid fibrils. These clusters challenge settled paradigms of protein condensation as the constituent protein molecules present features characteristic of both partially misfolded and native proteins. Here we employ the antimicrobial enzyme lysozyme and examine the similarities between mesoscopic clusters, amyloid structures, and disordered aggregates consisting of chemically modified protein. We show that the mesoscopic clusters are distinct from the other two classes of aggregates. Whereas cluster formation and amyloid oligomerization are both reversible, aggregation triggered by reduction of the intramolecular S-S bonds is permanent. In contrast to the amyloid structures, protein molecules in the clusters retain their enzymatic activity. Furthermore, an essential feature of the mesoscopic clusters is their constant radius of less than 50 nm. The amyloid and disordered aggregates are significantly larger and rapidly grow. These findings demonstrate that the clusters are a product of limited protein structural flexibility. In view of the role of the clusters in the nucleation of ordered protein solids, our results suggest that fine-tuning the degree of protein conformational stability is a powerful tool to control and direct the pathways of protein condensation.

  20. Asymmetric condensed dark matter

    Energy Technology Data Exchange (ETDEWEB)

    Aguirre, Anthony; Diez-Tejedor, Alberto, E-mail: aguirre@scipp.ucsc.edu, E-mail: alberto.diez@fisica.ugto.mx [Santa Cruz Institute for Particle Physics and Department of Physics, University of California, Santa Cruz, CA, 95064 (United States)

    2016-04-01

    We explore the viability of a boson dark matter candidate with an asymmetry between the number densities of particles and antiparticles. A simple thermal field theory analysis confirms that, under certain general conditions, this component would develop a Bose-Einstein condensate in the early universe that, for appropriate model parameters, could survive the ensuing cosmological evolution until now. The condensation of a dark matter component in equilibrium with the thermal plasma is a relativistic process, hence the amount of matter dictated by the charge asymmetry is complemented by a hot relic density frozen out at the time of decoupling. Contrary to the case of ordinary WIMPs, dark matter particles in a condensate must be lighter than a few tens of eV so that the density from thermal relics is not too large. Big-Bang nucleosynthesis constrains the temperature of decoupling to the scale of the QCD phase transition or above. This requires large dark matter-to-photon ratios and very weak interactions with standard model particles.

  1. Condenser performance monitoring and cleaning

    International Nuclear Information System (INIS)

    Walden, J.V.

    1998-01-01

    The main condenser at Ginna Station was retubed from admiralty brass to 316 stainless steel. A condenser performance monitoring spreadsheet was developed using EPRI guidelines after fouling was discovered. PEPSE computer models were used to determine the power loss and confirm the spreadsheet results. Cleaning of the condenser was performed using plastic scrubbers. Condenser performance improved dramatically following the cleaning. PEPSE, condenser spreadsheet performance, and actual observed plant data correlated well together. The fouling mechanism was determined to be a common lake bacteria and fungus growth which was combined with silt. Chlorination of the circulating water system at the allowable limits is keeping the biofouling under control

  2. Flexión y compresión compuestas en secciones rectangulares. Método en rotura del momento tope

    Directory of Open Access Journals (Sweden)

    Jiménez Montoya, P.

    1963-09-01

    Full Text Available This is a systematic summary of studies on rectangular sections subjected to compound loading and bending, calculated by the method of ultimate bending moment. The studies are part of the work which the author is preparing on reinforced and prestressed concrete. The method of ultimate bending moment, which is based on the rheological properties of concrete and on the new concepts of safety factors, has been accepted by the European Committee on Concrete (C. E. B. after being proposed by the Spanish Committee. It is very useful, since it is a simple procedure, and is also closer to reality than the classical methods. Also, this is the method of calculation adopted m the recent Specification H. A. 61, for reinforced concrete structures, issued by the Instituto Eduardo Torroja. The object of this paper is to give an account of the ultimate bending moment method, by establishing the equilibrium and compatibility equations, and applying them to the various design and calculation problems that most often arise. To simplify the task of the calculating technician, a number of monograms have been constructed, which are easy to operate. Only two of these are given in this paper, in order to limit the length of the latter.Constituye este trabajo un resumen ordenado del estudio de secciones rectangulares sometidas a flexión o compresión compuesta, por el método del momento tope, que forma parte de la obra que el autor tiene en preparación sobre hormigón armado y pretensado. El método del momento tope, basado en las propiedades reológicas del hormigón y en los nuevos conceptos del coeficiente de seguridad, ha sido admitido por el Comité Européen du Béton (C. E. B., a propuesta de la Comisión española, y es de mucha utilidad por constituir un procedimiento muy sencillo, y a la vez más de acuerdo con la realidad, que los métodos clásicos. Por otra parte, este es el método de cálculo adoptado por la reciente Instrucción H. A. 61, especial

  3. Obtención y caracterización de harinas compuestas de endospermo - germen de maíz y su uso en la preparación de arepas

    Directory of Open Access Journals (Sweden)

    HERNÁNDEZ Blanca D.

    1999-01-01

    Full Text Available La arepa, pan de maíz, es un producto elaborado a partir de harina precocida de endospermo de maíz, de elevado consumo en Colombia y Venezuela. Al obtener la harina de endospermo queda como subproducto el germen del que se extrae aceite que deja como residuo el germen desgrasado (GD. En el presente trabajo se formularon harinas compuestas del endospermo - GD. Se hicieron mezclas sustituyendo la harina precocida en 6, 8, 10 y 12%. Se evaluaron las propiedades físico - químicas, funcionales, sensoriales y nutricionales. Se encontró que al agregar el germen no aumenta significativamente la cantidad de proteína pero si mejora en más de un 300% la calidad nutricional de la misma, en la cual la relación de eficiencia proteica pasa de 0,16 hasta 1,04 en las harinas compuestas. La digestibilidad en las mezclas (> 89,5%, fue superior al valor obtenido para la harina precocida (84,02%. El contenido en fibra y grasa no varió significativamente en la harina compuesta, así mismo el color, peso específico, pH, separación de agua, adhesividad, absorción y solubilidad en agua no mostraron variaciones significativas. Sustituciones mayores a 6% mostraron pequeñas desviaciones respecto al rango establecido (3-5 cm para la expansión, sin afectar el amasado. Se prepararon arepas evaluándose su aceptabilidad. Se encontró que las arepas con 6% de GD fueron de mayor preferencia al compararlas con arepas de harina precocida, por lo que se concluyó que este porcentaje de sustitución sería el más viable, para enriquecer la harina precocida.

  4. ANÁLISE AO MICROSCÓPIO ELETRÔNICO DE VARREDURA DAS PROJEÇÕES DE RESINA ("TAGS" EM DENTES RESTAURADOS APÓS INTERVENÇÃO ENDODÔNTICA

    Directory of Open Access Journals (Sweden)

    SHIMABUKO Danilo Minor

    1998-01-01

    Full Text Available Avaliou-se in vitro, em 25 caninos humanos restaurados em nível coronário com resina composta fotopolimerizável após sofrerem intervenção endodôntica, a formação de projeções de resina ("tags" quanto a sua uniformidade e quantidade, variando-se o modo de aplicação, e a influência do ataque ácido e do uso de adesivos dentinários nas superfícies restauradas. Através da avaliação qualitativa por 3 observadores de fotomicrografias obtidas ao microscópio eletrônico de varredura, observou-se que houve formação de "tags" com melhor uniformidade no grupo em que se aplicou a resina fluida com bolinhas de algodão e imediata colocação da resina composta, sendo os dois materiais polimerizados conjuntamente, e com maior quantidade no grupo em que a resina fluida foi homogeneizada com jateamento de ar. A ausência de ataque ácido ou a não aplicação do sistema de adesão à dentina podem prejudicar a formação dos "tags" de resina.

  5. Experimental hydraulic analysis in conduction tunnels at the trunk section working as a channel considering compound roughness; Analisis hidraulico experimental en tuneles de conduccion en seccion baul trabajando como canal, considerando rugosidades compuestas

    Energy Technology Data Exchange (ETDEWEB)

    Marengo-Mogollon, Humberto; Cortes-Cortes, Carlos [Comision Federal de Electricidad (Mexico); Arreguin-Cortes, Felipe I [Comision Nacional del Agua (Mexico)

    2008-01-15

    This paper presents the roughness coefficients of a conduction tunnel at the trunk section working as a channel obtained experimentally using a hydraulic model of the diversion tunnel of the Hydroelectric Project called El Cajon (Mexico). A comparative analysis between experimental and theoretical coefficients obtained in the literature is shown. [Spanish] Se presentan los coeficientes de rugosidad compuesta de un tunel de conduccion en seccion baul trabajando como canal obtenidos en forma experimental en un modelo hidraulico del tunel de desvio del Proyecto Hidroelectrico El Cajon (Mexico). Se muestra un analisis comparativo entre los coeficientes experimentales y los teoricos obtenidos en la literatura.

  6. Condensed Matter Nuclear Science

    Science.gov (United States)

    Biberian, Jean-Paul

    2006-02-01

    1. General. A tribute to gene Mallove - the "Genie" reactor / K. Wallace and R. Stringham. An update of LENR for ICCF-11 (short course, 10/31/04) / E. Storms. New physical effects in metal deuterides / P. L. Hagelstein ... [et al.]. Reproducibility, controllability, and optimization of LENR experiments / D. J. Nagel -- 2. Experiments. Electrochemistry. Evidence of electromagnetic radiation from Ni-H systems / S. Focardi ... [et al.]. Superwave reality / I. Dardik. Excess heat in electrolysis experiments at energetics technologies / I. Dardik ... [et al.]. "Excess heat" during electrolysis in platinum/K[symbol]CO[symbol]/nickel light water system / J. Tian ... [et al.]. Innovative procedure for the, in situ, measurement of the resistive thermal coefficient of H(D)/Pd during electrolysis; cross-comparison of new elements detected in the Th-Hg-Pd-D(H) electrolytic cells / F. Celani ... [et al.]. Emergence of a high-temperature superconductivity in hydrogen cycled Pd compounds as an evidence for superstoihiometric H/D sites / A. Lipson ... [et al.]. Plasma electrolysis. Calorimetry of energy-efficient glow discharge - apparatus design and calibration / T. B. Benson and T. O. Passell. Generation of heat and products during plasma electrolysis / T. Mizuno ... [et al.]. Glow discharge. Excess heat production in Pd/D during periodic pulse discharge current in various conditions / A. B. Karabut. Beam experiments. Accelerator experiments and theoretical models for the electron screening effect in metallic environments / A. Huke, K. Czerski, and P. Heide. Evidence for a target-material dependence of the neutron-proton branching ratio in d+d reactions for deuteron energies below 20keV / A. Huke ... [et al.]. Experiments on condensed matter nuclear events in Kobe University / T. Minari ... [et al.]. Electron screening constraints for the cold fusion / K. Czerski, P. Heide, and A. Huke. Cavitation. Low mass 1.6 MHz sonofusion reactor / R. Stringham. Particle detection. Research

  7. The condensed matter physics

    International Nuclear Information System (INIS)

    Sapoval, B.

    1988-01-01

    The 1988 progress report of the laboratory of the Condensed Matter Physics (Polytechnic School, France), is presented. The Laboratory activities are related to the physics of semiconductors and disordered phases. The electrical and optical properties of the semiconductors, mixed conductor, superionic conductors and ceramics, are studied. Moreover, the interfaces of those systems and the sol-gel inorganic polymerization phenomena, are investigated. The most important results obtained, concern the following investigations: the electrochemical field effect transistor, the cathodoluminescence, the low energy secondary electrons emission, the fluctuations of a two-dimensional diffused junction and the aerogels [fr

  8. Topology in Condensed Matter

    CERN Document Server

    Monastyrsky, M I

    2006-01-01

    This book reports new results in condensed matter physics for which topological methods and ideas are important. It considers, on the one hand, recently discovered systems such as carbon nanocrystals and, on the other hand, new topological methods used to describe more traditional systems such as the Fermi surfaces of normal metals, liquid crystals and quasicrystals. The authors of the book are renowned specialists in their fields and present the results of ongoing research, some of it obtained only very recently and not yet published in monograph form.

  9. Air condensation plants

    International Nuclear Information System (INIS)

    Kelp, F.; Pohl, H.H.

    1978-01-01

    In this plant the steam is distributed by a ventilator from the bottom to symmetrically fixed, inclined cooling elements with tubes. The upper part of the current side of the cooling elements as well as the bottom part of the outflow side can be covered by cover plates via a control circuit. This way, part of the air amount is deviated and in case of unfavourable atmospheric conditions (cold) the air is heated. This heating is enough to prevent freezing of the condensate on the cooling tubes. (DG) [de

  10. Ice condenser experimental plan

    International Nuclear Information System (INIS)

    Kannberg, L.D.; Piepel, G.F.; Owczarski, P.C.; Liebetrau, A.M.

    1986-01-01

    An experimental plan is being developed to validate the computer code ICEDF. The code was developed to estimate the extent of aerosol retention in the ice compartments of pressurized water reactor ice condenser containment systems during severe accidents. The development of the experimental plan began with review of available information on the conditions under which the code will be applied. Computer-generated estimates of thermohydraulic and aerosol conditions entering the ice condenser were evaluated and along with other information, used to generate design criteria. The design criteria have been used for preliminary test assembly design and for generation of statistical test designs. Consideration of the phenomena to be evaluated in the testing program, as well as equipment and measurement limitations, have led to changes in the design criteria and to subsequent changes in the test assembly design and statistical test design. The overall strategy in developing the experimental plan includes iterative generation and evaluation of candidate test designs using computer codes for statistical test design and ICEDF for estimation of experimental results. Estimates of experimental variability made prior to actual testing will be verified by replicate testing at preselected design points

  11. Efecto del oxígeno y la glucosa en la metanogénesis y mineralización de resinas poliméricas

    Directory of Open Access Journals (Sweden)

    Ulises Durán Hinojosa

    2010-01-01

    Full Text Available En el presente trabajo se evaluó el efecto de la concentración de oxígeno disuelto (OD y la presencia de la glucosa en la metanogénesis y mineralización de los compuestos de resinas poliméricas, mediante cultivos en lote. El inóculo utilizado para los cultivos fueron lodos procedentes de un reactor de lecho de lodos con flujo ascendente UASB (por sus siglas en inglés, alimentado con glucosa y aguas residuales de resinas poliméricas, y 1,0 mg L-1 d-1 de oxígeno disuelto en estado estacionario. Todas las pruebas fueron realizadas con 1500 mg L-1 de demanda química de oxígeno, a 30±2° C, con 23,8 g L-1 de sólidos suspendidos volátiles como inóculo y una relación demanda química de oxígeno / sólidos suspendidos volátiles de 1. El efecto de diferentes concentraciones de oxígeno disuelto mostró que, para la glucosa, con bajas concentraciones (0,6 y 1,0 mg L-1 la eficiencia de remoción de la demanda química de oxígeno y la actividad metanogénicas permanecieron constantes, pero la eficiencia de remoción de la demanda química de oxígeno para los compuestos de resinas poliméricas aumentó 58,1±1% y el rendimiento de metano disminuyó, debido a que una mayor fracción del carbono alimentado fue mineralizada a dióxido de carbono, posiblemente por una ruta aerobia. Los resultados con diferentes proporciones de glucosa / compuestos de resinas poliméricas (CRP en presencia de 0,6 mg L-1 de oxígeno disuelto mostraron que la presencia de glucosa no mejoró la eliminación de los compuestos de resinas poliméricas. Sin embargo, la actividad metanogénica disminuyó en un 75% cuando solamente se usó a los compuestos de resinas poliméricas como sustrato, al compararla con la actividad metanogénica con glucosa como única fuente de carbono, sugiriendo que la glucosa no favorece la eliminación de los compuestos de resinas poliméricas, pero proporciona una mejor tolerancia al oxígeno. Se concluye que la presencia de bajas

  12. EFECTO DE LOS OBSTÁCULOS TIPO POLIMERO RESINA EN RENDIMIENTO DE REDES TCP/IP/IEEE 802.11g MODO AD-HOC

    OpenAIRE

    Márquez Barriobero, David

    2011-01-01

    La investigación tiene como objetivo primordial el desarrollo de un modelo matemático para evaluar el efecto de los obstáculos de tipo polímero resina en el rendimiento de redes TCP/IP/IEEE 802.11g modo ad-hoc; esto con el propósito de establecer la relación existente entre el diámetro de los obstáculos de tipo polímero resina y el rendimiento de una red inalámbrica en modo ad-hoc, al transmitir datos vía protocolo FTP. El tipo de investigación es explicativa con un diseño experimental. Los t...

  13. Optimal design of condenser weight

    International Nuclear Information System (INIS)

    Zheng Jing; Yan Changqi; Wang Jianjun

    2011-01-01

    The condenser is an important component in nuclear power plants, which dimension and weight will effect the economical performance and the arrangement of the nuclear power plants. In this paper, the calculation model is established according to the design experience. The corresponding codes are also developed, and the sensitivity of design parameters which influence the condenser weight is analyzed. The present design optimization of the condenser, taking the weight minimization as the objective, is carried out with the self-developed complex-genetic algorithm. The results show that the reference condenser design is far from the best scheme, and also verify the feasibility of the complex-genetic algorithm. (authors)

  14. Avaliação da toxicidade aguda e potencial neurotóxico do óleo-resina de copaíba (Copaifera reticulata Ducke, Fabaceae

    Directory of Open Access Journals (Sweden)

    Camile Giaretta Sachetti

    Full Text Available O óleo-resina de copaíba obtido do gênero Copaifera L., Fabaceae, é largamente utilizado na medicina popular como antiinflamatório, antimicrobiano e antitumoral. Porém, informações sobre seu potencial tóxico são escassos na literatura. O objetivo deste estudo foi estabelecer a toxicidade oral aguda e os possíveis efeitos neurotóxicos relacionados à ingestão do óleo-resina de Copaifera reticulata Ducke, Fabaceae, em ratas Wistar. O estudo foi conduzido com quinze ratas nulíparas distribuídas nos grupos de doses 300 e 2000 mg/kg pc de óleo-resina administrado por gavagem. Os resultados obtidos mostraram que nestas doses não houve sinais clínicos de toxicidade ou neurotoxicidade, alteração no consumo de ração ou alteração no peso corpóreo. A dose letal aguda foi estimada como maior que 2000 mg/kg pc e classificada como categoria 5, segundo o Guia OECD 423. Estes resultados indicam que existe uma relativa margem de segurança para o uso do óleo-resina de copaíba como agente terapêutico, embora estudos toxicológicos adicionais sejam ainda necessários, principalmente com a administração repetida de baixas doses.

  15. Biodetoxification of toxins generated from lignocellulose pretreatment using a newly isolated fungus, Amorphotheca resinae ZN1, and the consequent ethanol fermentation

    Directory of Open Access Journals (Sweden)

    Wang Wei

    2010-11-01

    Full Text Available Abstract Background Degradation of the toxic compounds generated in the harsh pretreatment of lignocellulose is an inevitable step in reducing the toxin level for conducting practical enzymatic hydrolysis and ethanol fermentation processes. Various detoxification methods have been tried and many negative outcomes were found using these methods, such as the massive freshwater usage and wastewater generation, loss of the fine lignocellulose particles and fermentative sugars and incomplete removal of inhibitors. An alternate method, biodetoxification, which degrades the toxins as part of their normal metabolism, was considered a promising option for the removal of toxins without causing the above problems. Results A kerosene fungus strain, Amorphotheca resinae ZN1, was isolated from the microbial community growing on the pretreated corn stover material. The degradation of the toxins as well as the lignocelluloses-derived sugars was characterized in different ways, and the results show that A. resinae ZN1 utilized each of these toxins and sugars as the sole carbon sources efficiently and grew quickly on the toxins. It was found that the solid-state culture of A. resinae ZN1 on various pretreated lignocellulose feedstocks such as corn stover, wheat straw, rice straw, cotton stalk and rape straw degraded all kinds of toxins quickly and efficiently. The consequent simultaneous saccharification and ethanol fermentation was performed at the 30% (wt/wt solid loading of the detoxified lignocellulosic feedstocks without a sterilization step, and the ethanol titer in the fermentation broth reached above 40 g/L using food crop residues as feedstocks. Conclusions The advantages of the present biodetoxification by A. resinae ZN1 over the known detoxification methods include zero energy input, zero wastewater generation, complete toxin degradation, processing on solid pretreated material, no need for sterilization and a wide lignocellulose feedstock spectrum

  16. Alternativas técnicas para o controle das alterações dimensionais das resinas acrílicas em prótese total

    OpenAIRE

    GOMEZ Tomas; MORI Matsuyoshi; CORRÊA Gerson de Arruda; MATSON Edmir

    1998-01-01

    Os autores propõem uma nova técnica para diminuição dos problemas provenientes das alterações dimensionais das resinas acrílicas utilizadas na confecção das próteses totais. Com essa proposta, conseguiu-se praticamente eliminar essas alterações dimensionais tão prejudiciais às próteses totais.

  17. Rugosidade e microscopia de força atômica de resinas compostas submetidas a diferentes métodos de polimento

    Directory of Open Access Journals (Sweden)

    Larissa Márcia Martins Alves

    2013-01-01

    Full Text Available Este trabalho avaliou a rugosidade e a topografia de superfície de resinas compostas submetidas a diferentes métodos de polimento. Foram utilizadas 5 resinas (Filtek Z350, Master Fill, Vênus, Charisma e Durafill VS e confeccionou-se 90 corpos de prova distribuídos em 6 grupos (n:15: SP: sem polimento; TB: ponta de borracha abrasiva; DL: disco de lixa em três granulações; FP: disco de feltro com pasta diamantada; ECS: escova de carbeto de silício; PS: ponta de silicone abrasiva. Após os polimentos, foram realizadas as análises da rugosidade com auxílio de um rugosímetro e da topografia de superfície com a microscopia de força atômica. Os valores foram tabulados e analisados estatisticamente pelos testes de Kruskal-Wallis, DUNN e ANOVA (α = 0,05. As médias variaram entre 0,01 µm (Filtek Z 350 - TB e 0,27 µm (Charisma - ECS. Concluiu-se que para todas as resinas testadas o melhor método de polimento foi o feltro com pasta diamantada (FP.

  18. Influência do tempo de fotopolimerização de diferentes resinas compostas na sorpção de água = Influence of polymerization time of different composites on water sorption

    Directory of Open Access Journals (Sweden)

    Guimarães, Fabrício Barbosa Rocha

    2008-01-01

    Full Text Available Objetivo: Verificar a influência do tempo de polimerização de resinas compostas na absorção de água por diferentes resinas compostas. Metodologia: As resinas multiuso Z250®, compactável P60® e de micropartículas A110® foram utilizadas para a confecção de corpos-de-prova (n=5 por grupo de acordo com o tempo de fotopolimerização (o indicado pelo fabricante, a metade e o dobro do tempo preconizado. A quantidade de água absorvida pelos espécimes foi medida pela variação da massa dos mesmos, que foram pesados imediatamente após sua confecção, a cada 24h por 10 dias, e após 15 e 30 dias. Os dados foram analisados por ANOVA e teste de Tukey. Resultados: A absorção de água das resinas compostas foi diferente quando o tempo de polimerização foi alterado. A resina de micropartículas teve o melhor comportamento perante a mudança no tempo de fotopolimerização, enquanto que a resina de multiuso foi a que mais absorveu água quando o tempo foi alterado para menos (P<0,05. Conclusão: O tempo de polimerização sugerido pelo fabricante deve ser respeitado para assegurar a manutenção das propriedades desses materiais, independentemente do tipo de resina utilizado

  19. Bose-Einstein Condensation

    International Nuclear Information System (INIS)

    Jaksch, D

    2003-01-01

    The Gross-Pitaevskii equation, named after one of the authors of the book, and its large number of applications for describing the properties of Bose-Einstein condensation (BEC) in trapped weakly interacting atomic gases, is the main topic of this book. In total the monograph comprises 18 chapters and is divided into two parts. Part I introduces the notion of BEC and superfluidity in general terms. The most important properties of the ideal and the weakly interacting Bose gas are described and the effects of nonuniformity due to an external potential at zero temperature are studied. The first part is then concluded with a summary of the properties of superfluid He. In Part II the authors describe the theoretical aspects of BEC in harmonically trapped weakly interacting atomic gases. A short and rather rudimentary chapter on collisions and trapping of atomic gases which seems to be included for completeness only is followed by a detailed analysis of the ground state, collective excitations, thermodynamics, and vortices as well as mixtures of BECs and the Josephson effect in BEC. Finally, the last three chapters deal with topics of more recent interest like BEC in optical lattices, low dimensional systems, and cold Fermi gases. The book is well written and in fact it provides numerous useful and important relations between the different properties of a BEC and covers most of the aspects of ultracold weakly interacting atomic gases from the point of view of condensed matter physics. The book contains a comprehensive introduction to BEC for physicists new to the field as well as a lot of detail and insight for those already familiar with this area. I therefore recommend it to everyone who is interested in BEC. Very clearly however, the intention of the book is not to provide prospects for applications of BEC in atomic physics, quantum optics or quantum state engineering and therefore the more practically oriented reader might sometimes wonder why exactly an equation is

  20. Condensed matter physics in electrochemistry

    International Nuclear Information System (INIS)

    Kornyshev, A.A.

    1991-01-01

    Some topics in electrochemistry are considered from the condensed matter physics viewpoint in relation to the problems discussed in this book. Examples of the successful application of condensed matter physics to electrochemistry are discussed together with prospective problems and pressing questions. (author). 127 refs, 4 figs

  1. Off gas condenser performance modelling

    International Nuclear Information System (INIS)

    Cains, P.W.; Hills, K.M.; Waring, S.; Pratchett, A.G.

    1989-12-01

    A suite of three programmes has been developed to model the ruthenium decontamination performance of a vitrification plant off-gas condenser. The stages of the model are: condensation of water vapour, NO x absorption in the condensate, RuO 4 absorption in the condensate. Juxtaposition of these stages gives a package that may be run on an IBM-compatible desktop PC. Experimental work indicates that the criterion [HNO 2 ] > 10 [RuO 4 ] used to determine RuO 4 destruction in solution is probably realistic under condenser conditions. Vapour pressures of RuO 4 over aqueous solutions at 70 o -90 o C are slightly lower than the values given by extrapolating the ln K p vs. T -1 relation derived from lower temperature data. (author)

  2. Estudo de resistência à tração de três sistemas adesivos associados a resina composta em superfícies dentinárias

    Directory of Open Access Journals (Sweden)

    MATOS Adriana Bona

    2001-01-01

    Full Text Available Este trabalho teve como objetivo comparar a resistência à tração de três sistemas adesivos associados a resina composta aderidos à superfície dentinária. Quarenta e cinco superfícies de dentina foram obtidas a partir de molares humanos extraídos, sobre elas foi preparado "smear layer" e foram divididas em 3 grupos: G1 adesivo autocondicionante + resina micro-híbrida; G2 adesivo de componente único + ácido e resina micro-híbrida e G3 adesivo convencional (ácido + "primer" + bond + resina micro-híbrida, aplicados de acordo com as instruções dos fabricantes. Os corpos-de-prova foram preparados para teste de tração, imersos em água destilada por 24 horas a 37ºC. Findo este tempo, o teste de tração foi realizado em máquina de ensaio Inströn com velocidade constante de 0,5 mm/min. Os resultados foram expressos em MPa e submetidos a análise de variância (p < 0,05. Os autores concluíram que: o tipo de sistema adesivo influenciou na resistência à tração das resinas compostas testadas; o sistema adesivo de componente único apresentou os melhores resultados de resistência adesiva.

  3. Biochemical analysis of the Hormoconis resinae fungal mycelium in the corrosion of aeronautical aluminium alloys

    Directory of Open Access Journals (Sweden)

    Araya, R.

    2007-06-01

    Full Text Available Biochemical analyses of the Hormoconis resinae fungal mycelium would explain behaviour differences of corrosive and non-corrosive strains on Al and its aeronautical alloys. In previous works its aggressiveness had been studied through SEM-EDX surface analysis, electrochemical techniques and immersion testing. In this paper separation of the proteins of the mycelium produced by a non-corrosive strain and its culture along three generations was performed. Cultures were prepared in batch in the presence and absence of pure Al and AA 2024, AA 7005 and AA 7075 alloys. The mycelia grown throughout the three generations increasingly
    recovered usual characteristics at the third replication, included their corrosiveness on Al and its alloys previously shown by all our strains. Amongst the bio-molecule fractions isolated and analysed during this preliminary study only the proteins revealed changes with the generation grown. When this fungal strain was cultured in the presence of alloy metal sheets electrophoresis of the protean fraction was correlative with the distinct mycelia behaviour observed, including corrosiveness on Al and its alloys.

    Las diferencias entre el comportamiento corrosivo y no corrosivo de una cepa del hongo Hormoconis resinae sobre aluminio y sus aleaciones aeronáuticas se explicarían a través de análisis bioquímicos del micelio. En trabajos previos, el comportamiento corrosivo se estudió mediante análisis de superficie SEM-EDX, técnicas electroquímicas y ensayos de inmersión. En este trabajo, se llevó a cabo la separación de proteínas del micelio producido por una cepa que perdió su corrosividad y su cultivo a través de tres generaciones. Cultivos en batch, en presencia y ausencia de aluminio y sus aleaciones AA 2024, AA 7005 y AA 7075, a través de tres generaciones del micelio crecido, fueron recuperando sus características, incluida su habitual corrosividad, en la tercera replicaci

  4. Characterization of spacecraft humidity condensate

    Science.gov (United States)

    Muckle, Susan; Schultz, John R.; Sauer, Richard L.

    1994-01-01

    When construction of Space Station Freedom reaches the Permanent Manned Capability (PMC) stage, the Water Recovery and Management Subsystem will be fully operational such that (distilled) urine, spent hygiene water, and humidity condensate will be reclaimed to provide water of potable quality. The reclamation technologies currently baselined to process these waste waters include adsorption, ion exchange, catalytic oxidation, and disinfection. To ensure that the baseline technologies will be able to effectively remove those compounds presenting a health risk to the crew, the National Research Council has recommended that additional information be gathered on specific contaminants in waste waters representative of those to be encountered on the Space Station. With the application of new analytical methods and the analysis of waste water samples more representative of the Space Station environment, advances in the identification of the specific contaminants continue to be made. Efforts by the Water and Food Analytical Laboratory at JSC were successful in enlarging the database of contaminants in humidity condensate. These efforts have not only included the chemical characterization of condensate generated during ground-based studies, but most significantly the characterization of cabin and Spacelab condensate generated during Shuttle missions. The analytical results presented in this paper will be used to show how the composition of condensate varies amongst enclosed environments and thus the importance of collecting condensate from an environment close to that of the proposed Space Station. Although advances were made in the characterization of space condensate, complete characterization, particularly of the organics, requires further development of analytical methods.

  5. Condensation in Nanoporous Packed Beds.

    Science.gov (United States)

    Ally, Javed; Molla, Shahnawaz; Mostowfi, Farshid

    2016-05-10

    In materials with tiny, nanometer-scale pores, liquid condensation is shifted from the bulk saturation pressure observed at larger scales. This effect is called capillary condensation and can block pores, which has major consequences in hydrocarbon production, as well as in fuel cells, catalysis, and powder adhesion. In this study, high pressure nanofluidic condensation studies are performed using propane and carbon dioxide in a colloidal crystal packed bed. Direct visualization allows the extent of condensation to be observed, as well as inference of the pore geometry from Bragg diffraction. We show experimentally that capillary condensation depends on pore geometry and wettability because these factors determine the shape of the menisci that coalesce when pore filling occurs, contrary to the typical assumption that all pore structures can be modeled as cylindrical and perfectly wetting. We also observe capillary condensation at higher pressures than has been done previously, which is important because many applications involving this phenomenon occur well above atmospheric pressure, and there is little, if any, experimental validation of capillary condensation at such pressures, particularly with direct visualization.

  6. Models of coherent exciton condensation

    International Nuclear Information System (INIS)

    Littlewood, P B; Eastham, P R; Keeling, J M J; Marchetti, F M; Simons, B D; Szymanska, M H

    2004-01-01

    That excitons in solids might condense into a phase-coherent ground state was proposed about 40 years ago, and has been attracting experimental and theoretical attention ever since. Although experimental confirmation has been hard to come by, the concepts released by this phenomenon have been widely influential. This tutorial review discusses general aspects of the theory of exciton and polariton condensates, focusing on the reasons for coherence in the ground state wavefunction, the BCS to Bose crossover(s) for excitons and for polaritons, and the relationship of the coherent condensates to standard lasers

  7. Models of coherent exciton condensation

    Energy Technology Data Exchange (ETDEWEB)

    Littlewood, P B [Theory of Condensed Matter, Cavendish Laboratory, Cambridge CB3 0HE (United Kingdom); Eastham, P R [Theory of Condensed Matter, Cavendish Laboratory, Cambridge CB3 0HE (United Kingdom); Keeling, J M J [Theory of Condensed Matter, Cavendish Laboratory, Cambridge CB3 0HE (United Kingdom); Marchetti, F M [Theory of Condensed Matter, Cavendish Laboratory, Cambridge CB3 0HE (United Kingdom); Simons, B D [Theory of Condensed Matter, Cavendish Laboratory, Cambridge CB3 0HE (United Kingdom); Szymanska, M H [Theory of Condensed Matter, Cavendish Laboratory, Cambridge CB3 0HE (United Kingdom)

    2004-09-08

    That excitons in solids might condense into a phase-coherent ground state was proposed about 40 years ago, and has been attracting experimental and theoretical attention ever since. Although experimental confirmation has been hard to come by, the concepts released by this phenomenon have been widely influential. This tutorial review discusses general aspects of the theory of exciton and polariton condensates, focusing on the reasons for coherence in the ground state wavefunction, the BCS to Bose crossover(s) for excitons and for polaritons, and the relationship of the coherent condensates to standard lasers.

  8. Bose condensation in (random traps

    Directory of Open Access Journals (Sweden)

    V.A. Zagrebnov

    2009-01-01

    Full Text Available We study a non-interacting (perfect Bose-gas in random external potentials (traps. It is shown that a generalized Bose-Einstein condensation in the random eigenstates manifests if and only if the same occurs in the one-particle kinetic-energy eigenstates, which corresponds to the generalized condensation of the free Bose-gas. Moreover, we prove that the amounts of both condensate densities are equal. This statement is relevant for justification of the Bogoliubov approximation} in the theory of disordered boson systems.

  9. Bond strength of hard chairside reline resins to a rapid polymerizing denture base resin before and after thermal cycling Resistência de união de resinas rígidas para reembasamento imediato a resina para base de prótese de rápida polimerização antes e após termociclagem

    Directory of Open Access Journals (Sweden)

    Karin Hermana Neppelenbroek

    2006-12-01

    Full Text Available PURPOSE: This study assessed the shear bond strength of 4 hard chairside reline resins (Kooliner, Tokuso Rebase Fast, Duraliner II, Ufi Gel Hard to a rapid polymerizing denture base resin (QC-20 processed using 2 polymerization cycles (A or B, before and after thermal cycling. MATERIALS AND METHODS: Cylinders (3.5 mm x 5.0 mm of the reline resins were bonded to cylinders of QC-20 polymerized using cycle A (boiling water-20 minutes or B (boiling water; remove heat-20 minutes; boiling water-20 minutes. For each reline resin/polymerization cycle combination, 10 specimens (groups CAt e CBt were thermally cycled (5 and 55 ºC; dwell time 30 seconds; 2,000 cycles; the other 10 were tested without thermal cycling (groups CAwt ad CBwt. Shear bond tests (0.5 mm/min were performed on the specimens and the failure mode was assessed. Data were analyzed by 3-way ANOVA and Newman-Keuls post-hoc test (alpha=.05. RESULTS: QC-20 resin demonstrated the lowest bond strengths among the reline materials (POBJETIVO: Esse estudo avaliou a resistência de união ao cisalhamento de 4 resinas rígidas para reembasamento imediato (Kooliner, Tokuso Rebase Fast, Duraliner II, Ufi Gel Hard a uma resina para base de prótese de rápida polimerização (QC-20 submetida a 2 ciclos de polimerização (A e B, antes e após termociclagem. MATERIAIS E MÉTODOS: Cilindros (3,5 mm x 5,0 mm das resinas reembasadoras foram unidas aos cilindros de resina QC-20 polimerizados pelo ciclo A (água fervente - 20 minutos ou B (água fervente; remoção do calor-20 minutos; água fervente-20 minutos. Para cada combinação resina reembasadora/ciclo de polimerização, 10 corpos-de-prova (grupos CAt e CBt foram termociclados (5 e 55 ºC; intervalo de tempo 30 segundos; 2.000 ciclos; os outros 10 foram testados sem termociclagem (grupos CAwt e CBwt. Os testes de resistência de união ao cisalhamento (0,5 mm/min foram realizados sobre os corpos-de-prova e o tipo de falha avaliado. Os dados foram

  10. Steam generators, turbines, and condensers. Volume six

    International Nuclear Information System (INIS)

    Anon.

    1986-01-01

    Volume six covers steam generators (How steam is generated, steam generation in a PWR, vertical U-tube steam generators, once-through steam generators, how much steam do steam generators make?), turbines (basic turbine principles, impulse turbines, reaction turbines, turbine stages, turbine arrangements, turbine steam flow, steam admission to turbines, turbine seals and supports, turbine oil system, generators), and condensers (need for condensers, basic condenser principles, condenser arrangements, heat transfer in condensers, air removal from condensers, circulating water system, heat loss to the circulating water system, factors affecting condenser performance, condenser auxiliaries)

  11. Condensation coefficient of water in a weak condensation state

    International Nuclear Information System (INIS)

    Kobayashi, Kazumichi; Watanabe, Shunsuke; Yamano, Daigo; Yano, Takeru; Fujikawa, Shigeo

    2008-01-01

    The condensation coefficient of water at a vapor-liquid interface is determined by combining shock tube experiments and numerical simulations of the Gaussian-BGK Boltzmann equation. The time evolution in thickness of a liquid film, which is formed on the shock tube endwall behind the shock wave reflected at the endwall, is measured with an optical interferometer consisting of the physical beam and the reference one. The reference beam is utilized to eliminate systematic noises from the physical beam. The growth rate of the film is evaluated from the measured time evolution and it is incorporated into the kinetic boundary condition for the Boltzmann equation. From a numerical simulation using the boundary condition, the condensation coefficient of water is uniquely deduced. The results show that, in a condition of weak condensation near a vapor-liquid equilibrium state, the condensation coefficient of water is almost equal to the evaporation coefficient estimated by molecular dynamics simulations near a vapor-liquid equilibrium state and it decreases as the system becomes a nonequilibrium state. The condensation coefficient of water is nearly identical with that of methanol [Mikami, S., Kobayashi, K., Ota, T., Fujikawa, S., Yano, T., Ichijo, M., 2006. Molecular gas dynamics approaches to interfacial phenomena accompanied with condensation. Exp. Therm. Fluid Sci. 30, 795-800].

  12. Condensation coefficient of water in a weak condensation state

    Science.gov (United States)

    Kobayashi, Kazumichi; Watanabe, Shunsuke; Yamano, Daigo; Yano, Takeru; Fujikawa, Shigeo

    2008-07-01

    The condensation coefficient of water at a vapor-liquid interface is determined by combining shock tube experiments and numerical simulations of the Gaussian-BGK Boltzmann equation. The time evolution in thickness of a liquid film, which is formed on the shock tube endwall behind the shock wave reflected at the endwall, is measured with an optical interferometer consisting of the physical beam and the reference one. The reference beam is utilized to eliminate systematic noises from the physical beam. The growth rate of the film is evaluated from the measured time evolution and it is incorporated into the kinetic boundary condition for the Boltzmann equation. From a numerical simulation using the boundary condition, the condensation coefficient of water is uniquely deduced. The results show that, in a condition of weak condensation near a vapor-liquid equilibrium state, the condensation coefficient of water is almost equal to the evaporation coefficient estimated by molecular dynamics simulations near a vapor-liquid equilibrium state and it decreases as the system becomes a nonequilibrium state. The condensation coefficient of water is nearly identical with that of methanol [Mikami, S., Kobayashi, K., Ota, T., Fujikawa, S., Yano, T., Ichijo, M., 2006. Molecular gas dynamics approaches to interfacial phenomena accompanied with condensation. Exp. Therm. Fluid Sci. 30, 795-800].

  13. Solar engineering - a condensed course

    Energy Technology Data Exchange (ETDEWEB)

    Broman, Lars

    2011-11-15

    The document represents the material covered in a condensed two-week course focusing on the most important thermal and PV solar energy engineering topics, while also providing some theoretical background.

  14. Capillary Condensation in Confined Media

    OpenAIRE

    Charlaix, Elisabeth; Ciccotti, Matteo

    2009-01-01

    28 pages - To appear in 2010 in the Handbook of Nanophysics - Vol 1 - Edited by Klaus Sattler - CRC Press; We review here the physics of capillary condensation of liquids in confined media, with a special regard to the application in nanotechnologies. The thermodynamics of capillary condensation and thin film adsorption are first exposed along with all the relevant notions. The focus is then shifted to the modelling of capillary forces, to their measurements techniques (including SFA, AFM and...

  15. Resistência à microtração entre uma cerâmica hidrotérmica, silanizada ou não, aderida à uma resina composta por um cimento resinoso

    OpenAIRE

    Lopes, Angela; Leite, Fabiola; Valandro, Luis Felipe; Siqueira, Luciana; Pimenta, Luiz André; Neisser, Maximiliano Piero

    2010-01-01

    Esse trabalho teve como objetivo avaliar a resistência adesiva entre uma cerâmica hidrotérmica (Symbio ceram, Degussa), silanizada ou não e aderida à uma resina composta (Filtec Z100- 3M ESPE) por um cimento resinoso (Panavia F, Kuraray). Foram confeccionados 2 blocos, divididos em 2 grupos assim constituídos: Grupo I-tratamento de superfície da cerâmica com ácido fluorídrico a 10% e união a um substrato (resina compost...

  16. Evaluación de la dispersión de pigmento en resinas acrílicas para la fabricación de dientes artificiales

    Directory of Open Access Journals (Sweden)

    Germán Ricaurte Avella

    2010-01-01

    Full Text Available En la primera etapa de fabricación de dientes artificiales los pigmentos se dispersan en seco en un polvo de resina acrílica conformado por finas partículas esféricas. Esta dispersión tiene características especiales diferentes a la dispersión de pigmentos en resinas líquidas usual en el campo de las pinturas y recubrimientos o en la fabricación de plásticos. No hay muchos reportes sobre los métodos de análisis y control de este tipo de procesos. En este trabajo se pretende evaluar el método de poder colorante, usual en la industria de recubrimientos, contrastando sus resultados con el porcentaje de área de pigmento adherida a las esferas de resina aplicando técnicas de procesamiento digital de imágenes (PDI a micrografías SEM. Se proponen y discuten, además, otros tres métodos alternativos basados en análisis de curvas de reflectancia, que permiten una evaluación rápida del proceso de dispersión, e incluso determinar el valor de la energía de la banda prohibida del pigmento. El método de poder colorante resulta ser el más sensible a las diferencias de dispersión. Finalmente, se aplican los cuatro métodos a una comparación entre tres procesos de molienda con diferentes energías y se discuten los resultados y las limitaciones de cada uno.

  17. Tableros de partículas de bambú (Bambusa vulgaris Schrad y resina poliuretana a base de aceite de rícino (Ricinus communis L.

    Directory of Open Access Journals (Sweden)

    Flávio Januário José

    Full Text Available Esta investigación tiene como objetivo la elaboración y la evaluación de tableros de partículas homogéneas aglomeradas, utilizándose dos materiales alternativos en la búsqueda de la sustentabilidad del proceso productivo. Fueron utilizadas partículas de Bambusa vulgaris Schrad por la rapidez del ciclo de producción de esta especie de bambú. Como pegante fue utilizada la resina poliuretana a base de aceite de ricino (Ricinus communis L., por su origen parcialmente renovable, y por ser considerada no tóxica. Para la caracterización del material, fueron fabricadas, en escala de laboratorio, tableros de partículas de bambú con dimensiones inferiores al 2.4 mm, combinadas con 5%, 10% y 15% de resina en relación a la masa de partículas de bambú. Probetas fueron evaluadas de acuerdo con las especificaciones de la norma NBR 14810 - Tableros de madera aglomerada. Antes de los ensayos de compresión las probetas fueron evaluadas por medio del ensayo no destructivo por ultra-sonido. Los resultados obtenidos indicaron que los tableros con el contenido de 10% de resina no fue estadísticamente diferente al contenido de 15%, siendo ambos superiores al contenido de 5%. La mayoría de las propiedades de los tableros fueron inferiores a aquellas de los tableros comerciales. No fue posible correlacionar la velocidad del pulso de ultra-sonido con la resistencia a la compresión longitudinal.

  18. Dual approaches for defects condensation

    Energy Technology Data Exchange (ETDEWEB)

    Rougemont, Romulo; Grigorio, Leonardo de Souza; Wotzasek, Clovis [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil); Guimaraes, Marcelo Santos [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil)

    2009-07-01

    Full text. Due to the fact that the QCD running coupling constant becomes larger as we go into the low energy (or large distance) limit of the theory, a perturbative treatment of its infrared (IR) region is impossible. In particular, a formal mathematical demonstration of color confinement and a complete physical understanding of the exact mechanism that confines quarks and gluons are two missing points in our current knowledge of the IR-QCD. It was known that due to the Meissner effect of expulsion of magnetic fields in a electric condensate that usual superconductors should confine magnetic monopoles. That point led to the conjecture that the QCD vacuum could be a condensate of chromomagnetic monopoles, a dual superconductor (DSC). Such a chromomagnetic condensate should be responsible for the dual Meissner effect which is expected to lead to the confinement of color charges immersed in this medium. In dual superconductor models of color confinement, magnetic monopoles appear as topological defects in points of the space where the abelian projection becomes singular. Also, condensation of other kinds of defects such as vortices in superfluids and line-like defects in solids are responsible for a great variety of phase transitions, which once more proves the relevance of the subject. In the present work we review two methods that allow us to approach the condensation of defects: the Kleinert Mechanism (KM) and the Julia-Toulouse Mechanism (JTM). We show that in the limit where the vortex gauge field goes to zero, which we identify as the signature of the condensation of defects in the dual picture, these are two equivalent dual prescriptions for obtaining an effective theory for a phase where defects are condensed, starting from the fundamental theory defined in the normal phase where defects are diluted. (author)

  19. Condensation: the new deal; Condensation: la nouvelle donne

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-06-01

    The principle of condensation boilers is based on the recovery of the latent heat of the steam generated by the combustion of natural gas. This technology was introduced in France at the end of the 80's but failed in its promise because of the complexity of the equipments available at that time. Today, constructors' offer is more mature and reliable and the context has changed. This technology can conciliate three goals: a mastery of energy consumptions, the comfort of the user and the respect of environment. This meeting organized by the research center of Gaz de France (Cegibat), was a good opportunity to makes a status of the market of individual condensation systems in France and in Europe, to present the situation of this technology today and the 10 golden rules for the fitting and maintenance of individual condensation boilers, and to present some technical references, examples and results of today's offer. (J.S.)

  20. Research progress of control of condensate depression for condenser

    Science.gov (United States)

    Liu, Ying; Liang, Run; Li, Fengyu

    2017-08-01

    It is introduced that significance and structure of the condensate depression control system. In accordance with controller devised procedure, we analyze and elaborate how to construct the lumped parameter and dynamic mathematical model which possesses distinct physics significance. Neural network model being called black-box model is also introduced. We analyze and contrast the control technique of condensate depression as conventional PI control, fuzzy PI control and fuzzy control. It is indicated that if the controller of condensate depression were devised inappropriate, while the steam discharged of turbine varying by a large margin, would result in the rotation rate of cooling water circulating pump accelerating at a great lick even to trigger the galloping danger which is less impressive for the units operating safely.

  1. Un nuevo sistema de diseño de embuticiones en láminas de acero para maximizar resistencia de losas compuestas A new system for designing embossments in steel sheets to increase composite slabs shear resistance

    Directory of Open Access Journals (Sweden)

    Melchor López Ávila

    2007-12-01

    Full Text Available Se presenta un resumen de algunos de los principales antecedentes históricos en el análisis de las losas compuestas con láminas metálicas colaborantes sometidas a flexión, así como de los principales métodos de diseño, instrumentación y ensayo aceptados por las distintas normas internacionales. Se analizan cada uno de los parámetros fundamentales que influencian el comportamiento estructural de las losas compuestas, y a partir del estudio numérico de estos se propone un método de optimización del sistema de embuticiones, implementado en hojas de cálculo, con el cual es posible estimar una resistencia a esfuerzos cortantes para las láminas de perfilado abierto y entregando los resultados de los parámetros más importantes, y que empleándolos en forma comparativa es posible determinar el sistema de embuticiones óptimo a incluir en una lámina de perfilado abierto. Aplicando el método propuesto obtuve un sistema de embuticiones tecnológicamente posible y con un coste mínimo de inversiones para una línea industrial de láminas de perfilado abierto.A summary is presented with the main historical background in the analysis of the composite slabs with steel sheets subjected to flexion, as well as of the main methods of design, instrumentation and tests accepted by different International Standards. They fundamental parameters that influence the structural behaviour of the composite slabs are analyzed, and with a numeric study an analytical optimization method of the embossments system, is proposed and implemented in a spread sheet is possible to estimate the shear resistance of open web sheets and by comparing them, is possible to determine the better embossments system to include in a open web sheet with such method. Applying the proposed method a technologically possible embossments system can be obtained with a minimum cost for an industrial line of open web sheets.

  2. Formación de complejos fármaco-resina usados en preparados de liberación prolongada

    Directory of Open Access Journals (Sweden)

    Susana Alba Delgado

    1998-12-01

    Full Text Available Se estudiaron los tiempos para alcanzar el equilibrio en reacciones de intercambio iónico durante la formación de sales complejas poliestireno divinil-benceno sulfonato, con los fármacos dexanfetamina, metilhomatropina y salbutamol. Se hicieron reaccionar sales de los fármacos en solución con la resina en su forma "sodio", cuantificándose a intervalos la concentración en el sobrenadante, siguiendo el avance de la reacción y determinando el punto de equilibrio. Se propone un estadístico simple que permite seleccionar el tiempo para dar por terminada la reacción, y se encuentran valores inferiores a los informados en la literatura. Se comenta la relación entre dimensión molecular y nivel de saturación del complejo.Time intervals required for reaching the proper balance of ion exchange reactions during the formation of polystirene-dyvinil-benzene-sulphonate complex salts with drugs such as dexamphetamina, metylhomatropine and salbutamol are analyzed. Drug salt solutions were caused to react with resin in "sodium" form, then supernadant concentration was estimated at intervals following the development of the reaction and determining the point of balance. A simple statistical method which makes it possible to determine the time when the reaction shall be finished was proposed, and also values lower than those reported in literature were found. Some comment on the association between molecular dimension and the saturation level of the drug-resine complex are made

  3. Resinas de intercambio iónico para prolongar la liberación de los fármacos

    Directory of Open Access Journals (Sweden)

    Héctor M Alfonso Zerquera

    2000-12-01

    Full Text Available Se realizó el estudio de las resinas de intercambio iónico como sistemas para liberación prolongada con atención a los factores que afectan la formación de los resinatos o complejos fármacoresina. También se estudió la liberación de los principios activos a partir de los complejos y de las formas terminadas que los contienen, evaluándose los factores que afectan dicho proceso y las cinéticas a las que se ajusta. Se revisaron las combinaciones de procesos tecnológicos (principalmente la formación de complejos iónicos y su recubrimiento que potencian la utilidad de los resinatos para prolongar la liberación a través de mecanismos combinados de intercambio iónico y difusión a través de membranas, combinaciones dirigidas a reducir las limitaciones inherentes a cada proceso por separado y conseguir un control eficaz de la liberación de fármacos iónicos.The study of the ion exchange resins as systems for the prolonged release was conducted, making emphasis on the factors affecting the formation of resinates or drug-resin complexes. The release of the active principles was also studied starting from the complexes and the finished forms containing them. The factors affecting this process and the kinetics to which it is adjusted were evaluated, too. The combinations of technological processes (mainly the formation of ion complexes and their coating potentiating the usefulness of resinates to prolong the release by combined mechanisms of ion exchange and difussion through membranes, combinations directed to reduce the limitations inherent to each process separately and to achieve an efficient control of the release of ion drugs, were reviewed.

  4. Interesantes aplicaciones de las resinas sintéticas en obras de ingeniería civil

    Directory of Open Access Journals (Sweden)

    Vié, G.

    1970-12-01

    Full Text Available The author describes the growing importance of epoxy resins in construction, especially in public works. A brief account is given of the physical and chemical properties, such as almost total resistance to chemical action; high anticorrosive strength; better mechanical strength than concrete; insensibility to icing-deicing cycles and thermal changes; high bond with most materials; no changes due to ageing; great resistance to wearing and abrasive actions; good aspect; high electrical resistance; and others. The article also describes some of its most common uses, including fillings, injections, fixings, industrial floorings, tunnel facing, and waterproofing of cracks. Examples of some recent uses in France are also cited.El autor describe la importancia creciente que han adquirido las resinas epoxi en la construcción y, particularmente, en las obras públicas. Hace una exposición sucinta de sus propiedades físicas y químicas más destacadas: resistencia química prácticamente total, poder anticorrosivo elevado, mejores características mecánicas que el hormigón, insensibilidad a los ciclos hielo-deshielo y a las variaciones térmicas, poder adhesivo notable para todos los materiales, ninguna modificación por envejecimiento, gran resistencia al desgaste y a la abrasión, efecto decorativo, y gran resistividad eléctrica; así como de las utilizaciones más usuales: recrecidos, inyecciones, empotramientos, suelos industriales, revestimientos en túneles, impermeabilización de fisuras, etc. Se añaden algunos ejemplos recientes de su empleo en Francia.

  5. Oxidación catalítica de a-pineno con metiltrioxorenio inmovilizado en resinas

    Directory of Open Access Journals (Sweden)

    Lina María González R.

    2004-01-01

    Full Text Available Se investigó la inmovilización del catalizador homogéneo metiltrioxorenio (MTO, CH3ReO3, en resinas basadas en vinilpiridina sintetizadas por diferentes procedimientos. Los catalizadores se caracterizaron por espectroscopia IR y UV-Vis y la composición elemental de nitrógeno y renio se determinó por ICP-MS. Los análisis FTIR indicaron la presencia de grupos ReO3 y ReO en los catalizadores heterogeneizados; en los análisis UV-Vis se observaron nuevas bandas después de tratar los soportes con MTO. La eficiencia de incorporación de renio fue mayor en PVP comercial y en el copolímero preparado en suspensión. Además, la oxidación del soporte disminuyó la incorporación del MTO. Los catalizadores se evaluaron en la oxidación de α-pineno con peróxido de hidrógeno. Los catalizadores soportados en PVP presentaron baja conversión del α-pineno (7%, pero la selectividad al epóxido de α-pineno fue alta (92%. Además, la más alta conversión del α-pineno (50% se obtuvo con el MTO en los soportes copolimerizados y oxidados; con MeCN/DCM como solvente se obtuvieron principalmente aldehído canfolénico y sobrerol, productos de rearreglo del epóxido. En general, la eficiencia del oxidante fue baja y ésta se favoreció en terbutanol y acetato de etilo como solventes

  6. Condensational theory of stationary tornadoes

    International Nuclear Information System (INIS)

    Makarieva, A.M.; Gorshkov, V.G.; Nefiodov, A.V.

    2011-01-01

    Using the Bernoulli integral for air streamline with condensing water vapor a stationary axisymmetric tornado circulation is described. The obtained profiles of vertical, radial and tangential velocities are in agreement with observations for the Mulhall tornado, world's largest on record and longest-lived among the three tornadoes for which 3D velocity data are available. Maximum possible vortex velocities are estimated. -- Highlights: → Water vapor condensation causes a logarithmic drop of air pressure towards tornado center. → The first ever theoretical description of tornado velocities is obtained. → The maximum vortex velocity grows logarithmically with decreasing tornado eye radius. → Air motion with high velocities can only develop in sufficiently large condensation areas.

  7. Introduction. Cosmology meets condensed matter.

    Science.gov (United States)

    Kibble, T W B; Pickett, G R

    2008-08-28

    At first sight, low-temperature condensed-matter physics and early Universe cosmology seem worlds apart. Yet, in the last few years a remarkable synergy has developed between the two. It has emerged that, in terms of their mathematical description, there are surprisingly close parallels between them. This interplay has been the subject of a very successful European Science Foundation (ESF) programme entitled COSLAB ('Cosmology in the Laboratory') that ran from 2001 to 2006, itself built on an earlier ESF network called TOPDEF ('Topological Defects: Non-equilibrium Field Theory in Particle Physics, Condensed Matter and Cosmology'). The articles presented in this issue of Philosophical Transactions A are based on talks given at the Royal Society Discussion Meeting 'Cosmology meets condensed matter', held on 28 and 29 January 2008. Many of the speakers had participated earlier in the COSLAB programme, but the strength of the field is illustrated by the presence also of quite a few new participants.

  8. Dynamics of inhomogeneous chiral condensates

    Science.gov (United States)

    Carlomagno, Juan Pablo; Krein, Gastão; Kroff, Daniel; Peixoto, Thiago

    2018-01-01

    We study the dynamics of the formation of inhomogeneous chirally broken phases in the final stages of a heavy-ion collision, with particular interest on the time scales involved in the formation process. The study is conducted within the framework of a Ginzburg-Landau time evolution, driven by a free energy functional motivated by the Nambu-Jona-Lasinio model. Expansion of the medium is modeled by one-dimensional Bjorken flow and its effect on the formation of inhomogeneous condensates is investigated. We also use a free energy functional from a nonlocal Nambu-Jona-Lasinio model which predicts metastable phases that lead to long-lived inhomogeneous condensates before reaching an equilibrium phase with homogeneous condensates.

  9. Scrutinizing the pion condensed phase

    Energy Technology Data Exchange (ETDEWEB)

    Carignano, Stefano; Mammarella, Andrea; Mannarelli, Massimo [INFN, Laboratori Nazionali del Gran Sasso, Assergi (Italy); Lepori, Luca [Universita di Padova, Dipartimento di Fisica e Astronomia, Padova (Italy); Universita dell' Aquila, Dipartimento di Scienze Fisiche e Chimiche, Coppito-L' Aquila (Italy); Pagliaroli, Giulia [INFN, Laboratori Nazionali del Gran Sasso, Assergi (Italy); Gran Sasso Science Institute, L' Aquila (Italy)

    2017-02-15

    When the isospin chemical potential exceeds the pion mass, charged pions condense in the zero-momentum state forming a superfluid. Chiral perturbation theory provides a very powerful tool for studying this phase. However, the formalism that is usually employed in this context does not clarify various aspects of the condensation mechanism and makes the identification of the soft modes problematic. We re-examine the pion condensed phase using different approaches within the chiral perturbation theory framework. As a first step, we perform a low-density expansion of the chiral Lagrangian valid close to the onset of the Bose-Einstein condensation. We obtain an effective theory that can be mapped to a Gross-Pitaevskii Lagrangian in which, remarkably, all the coefficients depend on the isospin chemical potential. The low-density expansion becomes unreliable deep in the pion condensed phase. For this reason, we develop an alternative field expansion deriving a low-energy Lagrangian analog to that of quantum magnets. By integrating out the ''radial'' fluctuations we obtain a soft Lagrangian in terms of the Nambu-Goldstone bosons arising from the breaking of the pion number symmetry. Finally, we test the robustness of the second-order transition between the normal and the pion condensed phase when next-to-leading-order chiral corrections are included. We determine the range of parameters for turning the second-order phase transition into a first-order one, finding that the currently accepted values of these corrections are unlikely to change the order of the phase transition. (orig.)

  10. Minimum Leakage Condenser Test Program

    International Nuclear Information System (INIS)

    1978-05-01

    This report presents the results and analysis of tests performed on four critical areas of large surface condensers: the tubes, tubesheets, tube/tubesheet joints and the water chambers. Significant changes in operation, service duty and the reliability considerations require that certain existing design criteria be verified and that improved design features be developed. The four critical areas were treated analytically and experimentally. The ANSYS finite element computer program was the basic analytical method and strain gages were used for obtaining experimental data. The results of test and analytical data are compared and recommendations made regarding potential improvement in condenser design features and analytical techniques

  11. Regeneración de una resina de cambio iónico para su uso en la disminución de la dureza del agua. Simulación animada del proceso.

    OpenAIRE

    Milla González, Miguel

    2015-01-01

    Mediante una sencilla animación se muestra la sustitución de los iones metálicos (calcio) por protones en la regeneración con HCl de una resina catiónica para su uso posterior en el ablandamiento de una muestra de agua.

  12. Sal de iodônio aumenta a resistência coesiva de uma resina adesiva experimental na presença de solvente

    Directory of Open Access Journals (Sweden)

    Fernanda B. Leal

    2013-01-01

    Full Text Available Este estudo avaliou o efeito da concentração de solvente na resistência coesiva de um adesivo experimental contendo um derivado do difeniliodônio. Uma blenda monomérica baseada em Bis-GMA, TEGDMA e HEMA foi utilizada como resina adesiva modelo. Foram avaliados dois sistemas de fotoiniciação: um sistema bináriocanforquinona (CQ e etil 4-dimetilamino benzoato (EDAB] e um sistema ternário [CQ, EDAB e hexafluorfosfato de difeniliodônio (DPI]. Nestas resinas foram adicionadas diferentes concentrações de etanol, 0, 5, 10, 20, 30, 40% e teste de resistência coesiva foi utilizado para investigar o efeito deste solvente sobre as propriedades do material. A presença de solvente reduziu a resistência coesiva do polímero, independentemente do sistema de fotoiniciação utilizado. Além disso, o uso do sal de iodônio no sistema de fotoiniciação aumentou a resistência coesiva quando comparado com o sistema binário, e independentemente da concentração de solvente, a resistência coesiva dos polímeros contendo difeniliodônio foi superior à do sistema binário de fotoiniciação.

  13. Dermatosis profesional por resina epoxi: Presentación de un caso clínico Professional dermatosis for epoxy resin: A clinical case report

    Directory of Open Access Journals (Sweden)

    S Gaviola

    2008-06-01

    Full Text Available Mostramos un caso de dermatosis profesional originado por plásticos (resinas epoxi y la importancia de la detección precoz. Las resinas epoxi son de gran utilización en todo tipo de industrias (artes graficas, construcción, electrónica, componentes de prótesis traumatológicas, prótesis odontológicas, etc. y sus componentes pueden ser causa de dermatitis de contacto irritativa y por sensibilización.We describe a case of professional dermatosis caused by exposition to plastic products (epoxy resin and importance of early detection. The epoxy resins are widely used in all types of industries (graphics arts, construction, electronics, traumathological and odontological prothesis, etc. and their components may be the cause of contact dermatitis and sensitivity. Risk factors at work with epoxy resins are present during the production base resins, hardening agents, plasticizers and dilutants increase the risk of exposition at work. This requires preventive measures and early diagnosis.

  14. Avaliação em curto e médio prazo da sorção e da solubilidade de resinas compostas à base de metacrilato e de silorano em saliva artificial

    Directory of Open Access Journals (Sweden)

    Isabel Cristina Celerino de Moraes Porto

    Full Text Available INTRODUÇÃO: A absorção/adsorção de moléculas de água por monômeros hidrofílicos dentro de materiais resinosos expostos à umidade da boca pode resultar em degradação. OBJETIVO: Este estudo avaliou sorção e solubilidade de resinas compostas à base de metacrilato e silorano em contato com saliva artificial, nos períodos de um dia (curto prazo, e 30 e 90 dias (médio prazo. MATERIAL E MÉTODO: Sessenta corpos de prova foram confeccionados com as resinas Filtek® Z250 e Filtek® P90 Silorano (3M/ESPE, e depois imersos em saliva artificial a 37 ± 1 ºC durante um, 30 e 90 dias. Os dados foram analisados usando-se ANOVA um fator/dois fatores seguido dos testes Tukey ou Tamhane (α = 0,05. RESULTADO: As médias de sorção das duas resinas aumentaram com o tempo (p = 0,001. A sorção de Z250 (1 e 90 d foi significativamente maior do que de P90 (p = 0,008, com valores semelhantes após 30 dias. A solubilidade das resinas também aumentou com o tempo, com diferença significativa entre todos os períodos (p = 0,001, exceto para a resina P90 (entre 1 e 30 d. Não houve diferença estatística significante entre os grupos Z250 (1 d e P90 (1 dia, Z250 (1 d e P90 (30 d, e Z250 (30 d e P90 (90 d. Para os demais pares, comprovaram-se diferenças significativas (p < 0,001. CONCLUSÃO: As propriedades de sorção e solubilidade das resinas compostas testadas foram influenciadas pelo tempo de exposição à saliva artificial. O silorano teve desempenho ora melhor ora semelhante à resina de metacrilato.

  15. On condensation-induced waves

    NARCIS (Netherlands)

    Cheng, W.; Luo, X.; Dongen, van M.E.H.

    2010-01-01

    Complex wave patterns caused by unsteady heat release due to cloud formation in confined compressible flows are discussed. Two detailed numerical studies of condensation-induced waves are carried out. First, the response of a flow of nitrogen in a slender Laval nozzle to a sudden addition of water

  16. KAON CONDENSATION IN NEUTRON STARS

    International Nuclear Information System (INIS)

    RAMOS, A.; SCHAFFNER-BIELICH, J.; WAMBACH, J.

    2001-01-01

    We discuss the kaon-nucleon interaction and its consequences for the change of the properties of the kaon in the medium. The onset of kaon condensation in neutron stars under various scenarios as well its effects for neutron star properties are reviewed

  17. Thermodynamic entanglement of magnonic condensates

    Science.gov (United States)

    Yuan, H. Y.; Yung, Man-Hong

    2018-02-01

    Over the past decade, significant progress has been achieved to create Bose-Einstein condensates (BECs) of magnetic excitations, i.e., magnons, at room temperature, which is a novel quantum many-body system with a strong spin-spin correlation, and contains potential applications in magnonic spintronics. For quantum information science, the magnonic condensates can become an attractive source of quantum entanglement, which plays a central role in most of the quantum information processing tasks. Here we theoretically study the entanglement properties of a magnon gas above and below the condensation temperature. We show that the thermodynamic entanglement of the spins is a manifestation of the off-diagonal long-range order; the entanglement of the condensate does not vanish, even if the spins are separated by an infinitely long distance, which is fundamentally distinct from the normal magnetic ordering below the Curie temperature. In addition, the phase-transition point occurs when the derivative of the entanglement changes abruptly. These results provide a theoretical foundation for a future investigation of the magnon BEC in terms of quantum entanglement.

  18. Rotary condenser for SC2

    CERN Multimedia

    1975-01-01

    During 1975 the SC2 performance was improved among other things by redesigning some of the elements of the ROTCO (Annual Report 1975, p. 55). The photo shows an interior wiew of the housing of the rotary condenser and of the sixteen sets of shaped stator blades.

  19. Approaching Bose-Einstein Condensation

    Science.gov (United States)

    Ferrari, Loris

    2011-01-01

    Bose-Einstein condensation (BEC) is discussed at the level of an advanced course of statistical thermodynamics, clarifying some formal and physical aspects that are usually not covered by the standard pedagogical literature. The non-conventional approach adopted starts by showing that the continuum limit, in certain cases, cancels out the crucial…

  20. Knoop hardness of enamel and shear bond strength of brackets bonded with composite resin with and without fluoride Dureza Knoop do esmalte e resistência ao cisalhamento de braquetes colados com resina composta com e sem flúor

    Directory of Open Access Journals (Sweden)

    Silvia Amélia Scudeler Vedovello

    2012-08-01

    Full Text Available OBJECTIVE: The aim of this study was to evaluate the Knoop hardness of enamel, shear bond strength and failure pattern (adhesive, bracket/resin interface or mixed after bonding and debonding brackets, using resin composite with fluoride (Ortho Lite Cure, Ortho Source® and without fluoride (Orthobond, Morelli®. METHODS: Fragments (6 mm x 6 mm of 40 bovine incisor crowns were embedded in acrylic self-polymerizing resin. The Knoop hardness measurements were performed before and after bonding metal brackets. The specimens were divided into two groups, according to composite resin: with fluoride (Ortho Lite Cure, Ortho Source® and without fluoride (Orthobond, Morelli®. After bonding, the specimens were submitted to demineralization and remineralization cycling for 14 days. Shear bond strength testing was performed in a universal test machine (EMIC, at 5 mm/min crosshead speed. RESULTS: There was no significant difference in shear bond strength between Groups I and II. After demineralization and remineralization procedures (DE/RE, the specimens bonded with Ortho Lite Cure showed higher Knoop hardness than Orthobond. For both groups there was predominance of failure at bracket/resin interface. CONCLUSION: specimens bonded with fluoride resin composite showed higher microhardness after DE/RE cycling than those bonded with resin composite without fluoride, although no difference in shear bond strength was found.OBJETIVO: o propósito deste estudo foi avaliar a dureza Knoop do esmalte, resistência ao cisalhamento e padrão de falha (adesiva; interface braquete/resina; e mista após a colagem e descolagem de braquetes, utilizando uma resina composta com flúor (Ortho Lite Cure, Ortho Source® e uma sem flúor (Orthobond, Morelli®. MÉTODOS: fragmentos (6mm x 6mm de 40 coroas de incisivos bovinos foram embutidos em resina acrílica autopolimerizável. A dureza Knoop foi avaliada antes e após a colagem dos braquetes metálicos. Os corpos de prova

  1. Modeling of Kerena Emergency Condenser

    Science.gov (United States)

    Bryk, Rafał; Schmidt, Holger; Mull, Thomas; Wagner, Thomas; Ganzmann, Ingo; Herbst, Oliver

    2017-12-01

    KERENA is an innovative boiling water reactor concept equipped with several passive safety systems. For the experimental verification of performance of the systems and for codes validation, the Integral Test Stand Karlstein (INKA) was built in Karlstein, Germany. The emergency condenser (EC) system transfers heat from the reactor pressure vessel (RPV) to the core flooding pool in case of water level decrease in the RPV. EC is composed of a large number of slightly inclined tubes. During accident conditions, steam enters into the tubes and condenses due to the contact of the tubes with cold water at the secondary side. The condensed water flows then back to the RPV due to gravity. In this paper two approaches for modeling of condensation in slightly inclined tubes are compared and verified against experiments. The first approach is based on the flow regime map. Depending on the regime, heat transfer coefficient is calculated according to specific semi-empirical correlation. The second approach uses a general, fully-empirical correlation. The models are developed with utilization of the object-oriented Modelica language and the open-source OpenModelica environment. The results are compared with data obtained during a large scale integral test, simulating loss of coolant accident performed at Integral Test Stand Karlstein (INKA). The comparison shows a good agreement.Due to the modularity of models, both of them may be used in the future in systems incorporating condensation in horizontal or slightly inclined tubes. Depending on his preferences, the modeller may choose one-equation based approach or more sophisticated model composed of several exchangeable semi-empirical correlations.

  2. Modeling of Kerena Emergency Condenser

    Directory of Open Access Journals (Sweden)

    Bryk Rafał

    2017-12-01

    Full Text Available KERENA is an innovative boiling water reactor concept equipped with several passive safety systems. For the experimental verification of performance of the systems and for codes validation, the Integral Test Stand Karlstein (INKA was built in Karlstein, Germany. The emergency condenser (EC system transfers heat from the reactor pressure vessel (RPV to the core flooding pool in case of water level decrease in the RPV. EC is composed of a large number of slightly inclined tubes. During accident conditions, steam enters into the tubes and condenses due to the contact of the tubes with cold water at the secondary side. The condensed water flows then back to the RPV due to gravity. In this paper two approaches for modeling of condensation in slightly inclined tubes are compared and verified against experiments. The first approach is based on the flow regime map. Depending on the regime, heat transfer coefficient is calculated according to specific semi-empirical correlation. The second approach uses a general, fully-empirical correlation. The models are developed with utilization of the object-oriented Modelica language and the open-source OpenModelica environment. The results are compared with data obtained during a large scale integral test, simulating loss of coolant accident performed at Integral Test Stand Karlstein (INKA. The comparison shows a good agreement.Due to the modularity of models, both of them may be used in the future in systems incorporating condensation in horizontal or slightly inclined tubes. Depending on his preferences, the modeller may choose one-equation based approach or more sophisticated model composed of several exchangeable semi-empirical correlations.

  3. Coherence and chaos in condensed matter

    International Nuclear Information System (INIS)

    Bishop, A.R.

    1989-01-01

    This paper discusses the following topics: nonlinearity in condensed matter; coherence and chaos in spatially extended condensed matter systems; nonlinearity and magnetism; and solitons and conducting polymers. 52 refs., 7 figs

  4. Some concepts in condensed phase chemical kinetics

    International Nuclear Information System (INIS)

    Adelman, S.A.

    1986-01-01

    Some concepts in condensed phase chemical kinetics which have emerged from a recent rigorous statistical mechanical treatment of condensed phase chemical reaction dynamics (S.A. Adelman, Adv. Chem. Phys.53:61 (1983)) are discussed in simple physical terms

  5. Pion condensation and neutron star dynamics

    International Nuclear Information System (INIS)

    Kaempfer, B.

    1983-01-01

    The question of formation of pion condensate via a phase transition in nuclear matter, especially in the core of neutron stars is reviewed. The possible mechanisms and the theoretical restrictions of pion condensation are summarized. The effects of ultradense equation of state and density jumps on the possible condensation phase transition are investigated. The possibilities of observation of condensation process are described. (D.Gy.)

  6. Condensed matter analogues of cosmology

    Science.gov (United States)

    Kibble, Tom; Srivastava, Ajit

    2013-10-01

    It is always exciting when developments in one branch of physics turn out to have relevance in a quite different branch. It would be hard to find two branches farther apart in terms of energy scales than early-universe cosmology and low-temperature condensed matter physics. Nevertheless ideas about the formation of topological defects during rapid phase transitions that originated in the context of the very early universe have proved remarkably fruitful when applied to a variety of condensed matter systems. The mathematical frameworks for describing these systems can be very similar. This interconnection has led to a deeper understanding of the phenomena in condensed matter systems utilizing ideas from cosmology. At the same time, one can view these condensed matter analogues as providing, at least in a limited sense, experimental access to the phenomena of the early universe for which no direct probe is possible. As this special issue well illustrates, this remains a dynamic and exciting field. The basic idea is that when a system goes through a rapid symmetry-breaking phase transition from a symmetric phase into one with spontaneously broken symmetry, the order parameter may make different choices in different regions, creating domains that when they meet can trap defects. The scale of those domains, and hence the density of defects, is constrained by the rate at which the system goes through the transition and the speed with which order parameter information propagates. This is what has come to be known as the Kibble-Zurek mechanism. The resultant scaling laws have now been tested in a considerable variety of different systems. The earliest experiments illustrating the analogy between cosmology and condensed matter were in liquid crystals, in particular on the isotropic-to-nematic transition, primarily because it is very easy to induce the phase transition (typically at room temperature) and to image precisely what is going on. This field remains one of the

  7. Charge Screening in a Charged Condensate

    International Nuclear Information System (INIS)

    Gabadadze, Gregory; Rosen, Rachel A.

    2009-01-01

    We consider a highly dense system of helium-4 nuclei and electrons in which the helium-4 nuclei have condensed. We present the condensation mechanism in the framework of low energy effective field theory and discuss the screening of electric charge in the condensate.

  8. Some issues in the ghost condensation scenario

    International Nuclear Information System (INIS)

    Anisimov, A.

    2004-01-01

    In the recently proposed 'ghost condensation' scenario a model of consistent infrared modification of gravity was suggested. We first review the basic ideas of this scenario. We discuss various phenomenological aspects of the ghost condensation, such as stability of the condensate, bounds on the UV cut-off scale of the corresponding effective field theory and other issues. (author)

  9. Computations for a condenser. Experimental results

    International Nuclear Information System (INIS)

    Walden, Jean.

    1975-01-01

    Computations for condensers are presented with experimental results. The computations are concerned with the steam flux at the condenser input, and inside the tube bundle. Experimental results are given for the flux inside the condenser sleeve and the flow passing through the tube bundle [fr

  10. CO2 capture by Condensed Rotational Separation

    NARCIS (Netherlands)

    Benthum, van R.J.; Kemenade, van H.P.; Brouwers, J.J.H.; Golombok, M.

    2010-01-01

    Condensed Rotational Separation (CRS) technology is a patented method to upgrade gas mixtures. A novel application is thecapture of CO2 from coal-combustion fired power stations: Condensed Contaminant Centrifugal Separation in Coal Combustion(C5sep). CRS involves partial condensation of a gas

  11. Modelling of film condensation in presence of non condensable gases

    International Nuclear Information System (INIS)

    Genevieve Geffraye; Dominique Bestion; Vladimir Kalitvianski

    2005-01-01

    Full text of publication follows: This paper presents recent developments in the modelling of the condensation due to heat removal from a wall with a possible presence of hydrogen, nitrogen, or air. This work is mainly concerned with nuclear reactor safety with particular reference to situations related to new reactor design, cold shutdown state and severe accident analysis. Film condensation of steam in presence of nitrogen and helium in a tube has been investigated in the COTURNE experiment in a rather large range of parameters, pressure (from 0.1 to 7 Mpa), heat flux (0.1 to 6 W/cm 2 ), mass fraction of noncondensable gas (0 to 1) and also in presence of superheated steam. The experiment represents a Steam Generator tube of a Pressurised Water Reactor and can simulate both co-current or countercurrent flow of steam and water.The models are implemented in the CATHARE code used for nuclear reactor thermal-hydraulics. The code uses two mass balance equations for liquid and gas, two momentum balance equations for liquid and gas and two energy balance equations for liquid and gas. Additional mass transport equations can be added for each non condensable gas. Heat transfers from wall to liquid film, from liquid to interface and gas to interface are modelled. The liquid film heat transfer coefficient is first investigated in pure saturated steam conditions in the pressure range from 0.1 to 7 Mpa. The CATHARE film condensation model in pure steam conditions is derived from Chen's correlation. Chen proposes a general correlation for the film condensation, covering the wavy-laminar and the turbulent film regimes and taking into account the interfacial friction effect. A large data base of laminar film regime was used including COTURNE data other available data found in the literature. The analysis of these data base suggests an influence of the liquid Reynolds number, according to the Nusselt theory, and also of the Eoetvoes number, with surface tension effects. A

  12. Fundamentals of condensed matter physics

    CERN Document Server

    Cohen, Marvin L

    2016-01-01

    Based on an established course and covering the fundamentals, central areas, and contemporary topics of this diverse field, Fundamentals of Condensed Matter Physics is a much-needed textbook for graduate students. The book begins with an introduction to the modern conceptual models of a solid from the points of view of interacting atoms and elementary excitations. It then provides students with a thorough grounding in electronic structure as a starting point to understand many properties of condensed matter systems - electronic, structural, vibrational, thermal, optical, transport, magnetic and superconductivity - and methods to calculate them. Taking readers through the concepts and techniques, the text gives both theoretically and experimentally inclined students the knowledge needed for research and teaching careers in this field. It features 200 illustrations, 40 worked examples and 150 homework problems for students to test their understanding. Solutions to the problems for instructors are available at w...

  13. Supersymmetry breaking by gaugino condensation

    International Nuclear Information System (INIS)

    Casas, J.A.

    1991-01-01

    We briefly review the status and some of the recent work on supersymmetry breaking by gaugino condensation effects in the context of superstring theories. This issue is intimately related to the structure of the effective potential coming from superstrings. Minimization of this not only allows to find the scale of supersymmetry breaking, but also to determine dynamically other fundamental parameters of the theory, in particular the gauge coupling constant at the unification point and the expectation values of the moduli which give the size and shape of the compactified space. In a multiple condensate scenario these get reasonable values which may, in turn, lead to a determination of the family mass hierarchy. Some directions for future work are examined too. (author). 23 refs

  14. Construcciones de madera compuestas para cerramientos autoportantes

    OpenAIRE

    Saleh Pascha,Khaled

    2013-01-01

    El entendimiento de la construcción como un ejercicio articulador de piezas y materiales recorre el argumento de este artículo, que presenta desarrollos de componentes constructivos que mezclan madera con hormigón o vidrio, para envolventes horizontales y verticales.

  15. Measuring condensate fraction in superconductors

    International Nuclear Information System (INIS)

    Chakravarty, Sudip; Kee, Hae-Young

    2000-01-01

    An analysis of off-diagonal long-range order in superconductors shows that the spin-spin correlation function is significantly influenced by the order if the order parameter is anisotropic on a microscopic scale. Thus, magnetic neutron scattering can provide a direct measurement of the condensate fraction of a superconductor. It is also argued that recent measurements in high-temperature superconductors come very close to achieving this goal. (c) 2000 The American Physical Society

  16. Atomistic modeling of dropwise condensation

    Energy Technology Data Exchange (ETDEWEB)

    Sikarwar, B. S., E-mail: bssikarwar@amity.edu; Singh, P. L. [Department of Mechanical Engineering, Amity University Uttar Pradesh, Noida (India); Muralidhar, K.; Khandekar, S. [Department of Mechanical Engineering, IIT Kanpur (India)

    2016-05-23

    The basic aim of the atomistic modeling of condensation of water is to determine the size of the stable cluster and connect phenomena occurring at atomic scale to the macroscale. In this paper, a population balance model is described in terms of the rate equations to obtain the number density distribution of the resulting clusters. The residence time is taken to be large enough so that sufficient time is available for all the adatoms existing in vapor-phase to loose their latent heat and get condensed. The simulation assumes clusters of a given size to be formed from clusters of smaller sizes, but not by the disintegration of the larger clusters. The largest stable cluster size in the number density distribution is taken to be representative of the minimum drop radius formed in a dropwise condensation process. A numerical confirmation of this result against predictions based on a thermodynamic model has been obtained. Results show that the number density distribution is sensitive to the surface diffusion coefficient and the rate of vapor flux impinging on the substrate. The minimum drop radius increases with the diffusion coefficient and the impinging vapor flux; however, the dependence is weak. The minimum drop radius predicted from thermodynamic considerations matches the prediction of the cluster model, though the former does not take into account the effect of the surface properties on the nucleation phenomena. For a chemically passive surface, the diffusion coefficient and the residence time are dependent on the surface texture via the coefficient of friction. Thus, physical texturing provides a means of changing, within limits, the minimum drop radius. The study reveals that surface texturing at the scale of the minimum drop radius does not provide controllability of the macro-scale dropwise condensation at large timescales when a dynamic steady-state is reached.

  17. Advances in condensed matter optics

    CERN Document Server

    Chen, Liangyao; Jiang, Xunya; Jin, Kuijuan; Liu, Hui; Zhao, Haibin

    2015-01-01

    This book describes some of the more recent progresses and developmentsin the study of condensed matter optics in both theoretic and experimental fields.It will help readers, especially graduate students and scientists who are studying and working in the nano-photonic field, to understand more deeply the characteristics of light waves propagated in nano-structure-based materials with potential applications in the future.

  18. LOFCON-LOFT condenser program

    International Nuclear Information System (INIS)

    Lemmon, E.C.; MacKay, D.B.

    1978-01-01

    LOFCON is a program developed for the LOFT air condenser system contained in the secondary coolant system. Although the basic theory described herein is general, the program given is not--it is specifically for the LOFT configuration. LOFCON is presented in subroutine form so that it may be easily incorporated into a larger program describing the complete secondary side. Specifically LOFCON was written to be incorporated into the detailed CSMP model of the LOFT secondary coolant system simulation

  19. Tratamiento de protección para tuberías de hormigón pretensado a base de resinas sintéticas (epoxi y poliuretano

    Directory of Open Access Journals (Sweden)

    Soria Santamaría, Francisco

    1977-12-01

    Full Text Available Amongst the different systems of protection used against the corrosion phenomenon under stress, we find those which physically try to prevent the corrosive agent from reaching the prestressed steel. Such is the case of water-proofing by means of synthetic resin-base membranes. The article describes the different tests to which this type of membrane should be submitted, with regard to the type of concrete used. It is also necessary to take into consideration the peculiarities of each job. The object of the tests made was to show the ideal characteristics of epoxy and polyurethane synthetic resins, especially formulated for specific functions. Three kinds of solutions are established with the use of these resins in those cases of protection against «aggressive» liquids, coming from water pipe exteriors, subjected to high pressures, where prestressed concrete piping has been used to solve this problem. Details are given on a specific job carried out in which one of the mentioned solutions was used.Entre los distintos sistemas de protección contra el fenómeno de corrosión bajo tensión, se encuentran aquellos que tratan de impedir físicamente que el agente corrosivo llegue al acero pretensado. Este es el caso de las impermeabilizaciones mediante membranas a base de resinas sintéticas. En el artículo se describen distintos ensayos a que deben someterse este tipo de membranas en lo que respecta al hormigón soporte. Es preciso, además, adaptarse a las particularidades propias del tipo de obra a que van destinadas. El objetivo de los ensayos ha sido el mostrar la idoneidad de resinas sintéticas de epoxi y de poliuretano, específicamente formuladas para unas funciones concretas. Se establecen tres tipos de soluciones mediante el empleo de las citadas resinas, en el caso de protección, respecto a líquidos «agresivos» provenientes del exterior en conducciones de agua, sometidas a altas presiones, en tuberías de hormig

  20. Análise de custo de materiais utilizados em restaurações dentárias em resina composta

    Directory of Open Access Journals (Sweden)

    Eduardo Hebling

    Full Text Available INTRODUÇÃO: As resinas compostas são materiais usualmente utilizados em restaurações dentárias diretas de dentes posteriores. O custo dos materiais faz parte do cálculo do valor dos honorários odontológicos. OBJETIVO: O objetivo deste trabalho foi determinar e analisar o valor total do custo dos materiais utilizados para a confecção de restaurações dentárias diretas de dentes posteriores em resina composta. MATERIAL E MÉTODO: O cálculo dos custos foi baseado no método de sistema de custeio variável. A lista dos materiais foi obtida por meio de consulta a uma banca de juízes e baseada nos padrões de excelência comprovados na literatura para atendimento em equipe. Os valores dos materiais foram obtidos de uma média dos valores consultados no mercado fornecedor. As repetições foram obtidas de preparos cavitários Classes I e II em dentes pré-molares e molares artificiais pré-fabricados. Os materiais foram quantificados para cada tipo de preparo. As resinas compostas utilizadas foram pesadas em balança de precisão após a sua inserção em cada tipo de preparo. Os dados foram avaliados por estatística descritiva e pelos testes de Mann-Whitney e Kruskal-Wallis. RESULTADO: O custo encontrado para restauração de Classe I foi de R$17,56 e, para a de Classe II, de R$17,73. Não houve diferença estatística no custo entre os tipos de preparo e de dentes, sendo a média total de R$17,65. CONCLUSÃO: Os valores encontrados podem ser utilizados no cálculo do valor final do procedimento restaurador, auxiliando na gestão de serviços odontológicos públicos ou privados.

  1. Theory of laminar film condensation

    CERN Document Server

    Fujii, Tetsu

    1991-01-01

    Since the petroleum crisis in the 1970s, a lot of effort to save energy was made in industry, and remarkable achievements have been made. In the research and development concerning thermal energy, however, it was clar­ ified that one of the most important problems was manufacturing con­ densing systems with smaller size and higher performance. To solve this problem we need a method which synthesizes selections_ of the type of con­ denser, cooling tube and its arrangement, assessment of fouling on the cooling surfaces, consideration of transient characteristics of a condenser, etc. The majority of effort, however, has been to devise a surface element which enhances the heat transfer coefficient in condensation of a single or multicomponent vapor. Condensation phenomena are complexly affected by a lot of physical property values, and accordingly the results of theo­ retical research are expressed with several dimensionless parameters. On the other hand, the experimental research is limited to those with som...

  2. Scandinavian experience of titanium condensers

    International Nuclear Information System (INIS)

    Multer, I.; Hedstroem, M.

    1985-01-01

    The Albrass condenser tubing in Sweden and Finnish nuclear power plants has caused much concern. After the appearance of the first tube leak, the deterioration has been very rapid. A typical development is represented by the Ringhals unit 2 eddy current (EC) measurements. They are, despite the difference in salinity, almost identical with Forsmark units 1 and 2 and units 1 and 2 of the TVO power company at Olkiluoto, Finland. For instance, in summer 1984, 3000 tubes were plugged in TVO 2 after four years of operation. The cause was pitting and/or erosion-corrosion. The failure rate, although the plugging criteria have been different from the EPRI concept, has exceeded that reported in the US and UK; and it has been necessary, especially with the strict feed water chemistry requirements in the PWR's, to arrange for retubing after a very short time, approximately 3 years after the first leak. The history of the nuclear plant condensers is shown; the average condenser life span has been approximately 6.5 years

  3. Accelerators for condensed matter research

    International Nuclear Information System (INIS)

    Williams, P.R.

    1990-01-01

    The requirement for high energy, high luminosity beams has stimulated the science and engineering of accelerators to a point where they open up opportunities for new areas of scientific application to benefit from the advances driven by particle physics. One area of great importance is the use of electron or positron storage rings as a source of intense VUV or X-ray synchrotron radiation. An accelerator application that has grown in prominence over the last 10 years has been spallation neutron sources. Neutrons offer an advantage over X-rays as a condensed matter probe because the neutron energy is usually of the same order as the room temperature thermal energy fluctuations in the sample being studied. Another area in which accelerators are playing an increasingly important role in condensed matter research concerns the use of Mu mesons, Muons, as a probe. This paper also presents a description of the ISIS Spallation Neutron Source. The design and status of the facility are described, and examples are given of its application to the study of condensed matter. (N.K.)

  4. Condensation on Slippery Asymmetric Bumps

    Science.gov (United States)

    Park, Kyoo-Chul; Kim, Philseok; Aizenberg, Joanna

    2016-11-01

    Controlling dropwise condensation by designing surfaces that enable droplets to grow rapidly and be shed as quickly as possible is fundamental to water harvesting systems, thermal power generation, distillation towers, etc. However, cutting-edge approaches based on micro/nanoscale textures suffer from intrinsic trade-offs that make it difficult to optimize both growth and transport at once. Here we present a conceptually different design approach based on principles derived from Namib desert beetles, cacti, and pitcher plants that synergistically couples both aspects of condensation and outperforms other synthetic surfaces. Inspired by an unconventional interpretation of the role of the beetle's bump geometry in promoting condensation, we show how to maximize vapor diffusion flux at the apex of convex millimetric bumps by optimizing curvature and shape. Integrating this apex geometry with a widening slope analogous to cactus spines couples rapid drop growth with fast directional transport, by creating a free energy profile that drives the drop down the slope. This coupling is further enhanced by a slippery, pitcher plant-inspired coating that facilitates feedback between coalescence-driven growth and capillary-driven motion. We further observe an unprecedented six-fold higher exponent in growth rate and much faster shedding time compared to other surfaces. We envision that our fundamental understanding and rational design strategy can be applied to a wide range of phase change applications.

  5. Condensation During Nuclear Reactor Loca

    International Nuclear Information System (INIS)

    Rihan, Y.; Teamah, M.; Sorour, M.; Soliman, S.

    2008-01-01

    Two-phase channel flow with condensation is a common phenomenon occurs in a number of nuclear reactor accident scenarios. It also plays an important role during the operation of the safety coolant injection systems in advanced nuclear reactors. Semiempirical correlations and simple models based on the analogy between heat and mass transfer processes have been previously applied. Rigorous models, compatible with the state-of-the-art numerical algorithms used in thermal-hydraulic computer codes, are scare, and are of great interest. The objective of this research is to develop a method for modeling condensation, with noncondensable gases, compatible with the state-of-the-art numerical methods for the solution of multi-phase field equations. A methodology for modeling condensation, based on the stagnant film theory, and compatible with the reviewed numerical algorithms, is developed. The model treats the coupling between the heat and mass transfer processes, and allows for an implicit treatment of the mass and momentum exchange terms as the gas-liquid interphase, without iterations. The developed model was used in the application of loss of coolant in pressurized water reactor accidents

  6. Multiple spectator condensates from inflation

    Science.gov (United States)

    Hardwick, Robert J.

    2018-05-01

    We investigate the development of spectator (light test) field condensates due to their quantum fluctuations in a de Sitter inflationary background, making use of the stochastic formalism to describe the system. In this context, a condensate refers to the typical field value found after a coarse-graining using the Hubble scale H, which can be essential to seed the initial conditions required by various post-inflationary processes. We study models with multiple coupled spectators and for the first time we demonstrate that new forms of stationary solution exist (distinct from the standard exponential form) when the potential is asymmetric. Furthermore, we find a critical value for the inter-field coupling as a function of the number of fields above which the formation of stationary condensates collapses to H. Considering some simple two-field example potentials, we are also able to derive a lower limit on the coupling, below which the fluctuations are effectively decoupled, and the standard stationary variance formulae for each field separately can be trusted. These results are all numerically verified by a new publicly available python class (nfield) to solve the coupled Langevin equations over a large number of fields, realisations and timescales. Further applications of this new tool are also discussed.

  7. Modelación numérica con validación experimental aplicada al estudio del comportamiento de conectores tipo perno de estructuras compuestas de hormigón y acero

    Directory of Open Access Journals (Sweden)

    Jorge Bonilla

    2015-04-01

    Full Text Available En este trabajo se realiza un estudio del comportamiento de conectores tipo perno de estructuras compuestas de hormigón y acero mediante la simulación numérica del ensayo push out en sección viga-losa maciza de hormigón. Se analiza el comportamiento de los materiales en régimen no lineal, empleándose en un primer caso un modelo bilineal con criterio de rotura de Von Mises para el acero y el hormigón, y en un segundo caso un Modelo de Daño Plástico para el hormigón. Como herramienta para la modelación numérica se emplea el programa computacional ABAQUS. Se aborda el procedimiento metodológico de modelación numérica del ensayo de conectores. Se observa una buena correspondencia existente entre los resultados numéricos y experimentales, evidenciándose la efectividad del uso del Método de Elementos Finitos para el estudio del comportamiento de conectores. Finalmente, respaldado por los estudios numéricos y experimentales, se realiza una valoración de precisión en la estimación de la capacidad resistente de los conectores obtenida a partir de las normativas: AISC-LRFD (2005, Eurocódigo 4 (2004 y la Normativa Ramal Cubana NR-080-2004, observando que dichas normativas sobreestiman este valor en muchos casos.

  8. Quality factors to consider in condensate selection

    Energy Technology Data Exchange (ETDEWEB)

    Lywood, B. [Crude Quality Inc., Edmonton, AB (Canada)

    2009-07-01

    Many factors must be considered when assessing the feasibility of using condensates as a diluent for bitumen or heavy crude production blending. In addition to commercial issues, the effect of condensate quality is a key consideration. In general, condensate quality refers to density and viscosity. However, valuation decisions could be enhanced through the expansion of quality definitions and understanding. This presentation focused on the parameters that are important in choosing a diluent grade product. It also reviewed pipeline and industry specifications and provided additional information regarding general properties for bitumen and condensate compatibility; sampling and quality testing needs; and existing sources of information regarding condensate quality. tabs., figs.

  9. Ghost condensate and generalized second law

    International Nuclear Information System (INIS)

    Mukohyama, Shinji

    2009-01-01

    Dubovsky and Sibiryakov recently proposed a scenario in which particles of different species propagate with different speeds due to their direct couplings to ghost condensate. It was argued that this extended version of ghost condensate allows a gedanken experiment leading to violation of the generalized second law. However, in the original ghost condensate scenario, difference in propagation speeds is suppressed by M 2 /M Pl 2 , where M is the order parameter of spontaneous Lorentz breaking and M Pl is the Planck scale. In this case the energy transfer necessary for the gedanken experiment is so slow that the timescale of decrease of entropy, if any, is always longer than the Jeans timescale of ghost condensate. Hence the generalized second law is not violated by the gedanken experiment in the original ghost condensate scenario. This conclusion trivially extends to gauged ghost condensation by taking into account accretion of gauged ghost condensate into a black hole.

  10. Universal Themes of Bose-Einstein Condensation

    Science.gov (United States)

    Proukakis, Nick P.; Snoke, David W.; Littlewood, Peter B.

    2017-04-01

    Foreword; List of contributors; Preface; Part I. Introduction: 1. Universality and Bose-Einstein condensation: perspectives on recent work D. W. Snoke, N. P. Proukakis, T. Giamarchi and P. B. Littlewood; 2. A history of Bose-Einstein condensation of atomic hydrogen T. Greytak and D. Kleppner; 3. Twenty years of atomic quantum gases: 1995-2015 W. Ketterle; 4. Introduction to polariton condensation P. B. Littlewood and A. Edelman; Part II. General Topics: Editorial notes; 5. The question of spontaneous symmetry breaking in condensates D. W. Snoke and A. J. Daley; 6. Effects of interactions on Bose-Einstein condensation R. P. Smith; 7. Formation of Bose-Einstein condensates M. J. Davis, T. M. Wright, T. Gasenzer, S. A. Gardiner and N. P. Proukakis; 8. Quenches, relaxation and pre-thermalization in an isolated quantum system T. Langen and J. Schmiedmayer; 9. Ultracold gases with intrinsic scale invariance C. Chin; 10. Berezinskii-Kosterlitz-Thouless phase of a driven-dissipative condensate N. Y. Kim, W. H. Nitsche and Y. Yamamoto; 11. Superfluidity and phase correlations of driven dissipative condensates J. Keeling, L. M. Sieberer, E. Altman, L. Chen, S. Diehl and J. Toner; 12. BEC to BCS crossover from superconductors to polaritons A. Edelman and P. B. Littlewood; Part III. Condensates in Atomic Physics: Editorial notes; 13. Probing and controlling strongly correlated quantum many-body systems using ultracold quantum gases I. Bloch; 14. Preparing and probing chern bands with cold atoms N. Goldman, N. R. Cooper and J. Dalibard; 15. Bose-Einstein condensates in artificial gauge fields L. J. LeBlanc and I. B. Spielman; 16. Second sound in ultracold atomic gases L. Pitaevskii and S. Stringari; 17. Quantum turbulence in atomic Bose-Einstein condensates N. G. Parker, A. J. Allen, C. F. Barenghi and N. P. Proukakis; 18. Spinor-dipolar aspects of Bose-Einstein condensation M. Ueda; Part IV. Condensates in Condensed Matter Physics: Editorial notes; 19. Bose

  11. Black holes in the ghost condensate

    International Nuclear Information System (INIS)

    Mukohyama, Shinji

    2005-01-01

    We investigate how the ghost condensate reacts to black holes immersed in it. A ghost condensate defines a hypersurface-orthogonal congruence of timelike curves, each of which has the tangent vector u μ =-g μν ∂ ν φ. It is argued that the ghost condensate in this picture approximately corresponds to a congruence of geodesics. In other words, the ghost condensate accretes into a black hole just like a pressureless dust. Correspondingly, if the energy density of the ghost condensate at large distance is set to an extremely small value by cosmic expansion then the late-time accretion rate of the ghost condensate should be negligible. The accretion rate remains very small even if effects of higher derivative terms are taken into account, provided that the black hole is sufficiently large. It is also discussed how to reconcile the black-hole accretion with the possibility that the ghost condensate might behave like dark matter

  12. Endogenous or exogenous spreading of HIV-1 in Nordrhein-Westfalen, Germany, investigated by phylodynamic analysis of the RESINA Study cohort.

    Science.gov (United States)

    Lawyer, Glenn; Schülter, Eugen; Kaiser, Rolf; Reuter, Stefan; Oette, Mark; Lengauer, Thomas

    2012-08-01

    HIV's genetic instability means that sequence similarity can illuminate the underlying transmission network. Previous application of such methods to samples from the United Kingdom has suggested that as many as 86% of UK infections arose outside of the country, a conclusion contrary to usual patterns of disease spread. We investigated transmission networks in the Resina cohort, a 2,747 member sample from Nordrhein-Westfalen, Germany, sequenced at therapy start. Transmission networks were determined by thresholding the pairwise genetic distance in the pol gene at 96.8% identity. At first blush the results concurred with the UK studies. Closer examination revealed four large and growing transmission networks that encompassed all major transmission groups. One of these formed a supercluster containing 71% of the sex with men (MSM) subjects when the network was thresholded at levels roughly equivalent to those used in the UK studies, though methodological differences suggest that this threshold may be too generous in the current data. Examination of the endo- versus exogenesis hypothesis by testing whether infections that were exogenous to Cologne or to Dusseldorf were endogenous to the greater region supported endogenous spread in MSM subjects and exogenous spread in the endemic transmission group. In intravenous drug using group subjects, it depended on viral strain, with subtype B sequences appearing to have origin exogenous to the Resina data, while non-B sequences (primarily subtype A) were almost completely endogenous to their local community. These results suggest that, at least in Germany, the question of endogenous versus exogenous linkages depends on subject group.

  13. Quantum tunnelling in condensed media

    CERN Document Server

    Kagan, Yu

    1992-01-01

    The essays in this book deal with of the problem of quantum tunnelling and related behavior of a microscopic or macroscopic system, which interacts strongly with an ""environment"" - this being some form of condensed matter. The ""system"" in question need not be physically distinct from its environment, but could, for example, be one particular degree of freedom on which attention is focussed, as in the case of the Josephson junction studied in several of the papers. This general problem has been studied in many hundreds, if not thousands, of articles in the literature, in contexts as diverse

  14. Method of continuously cleaning condensers

    International Nuclear Information System (INIS)

    Tomita, Akira; Takahashi, Sankichi.

    1982-01-01

    Purpose: To prevent marine livings from depositing to the inside of ball recycling pipeways. Method: Copper electrodes are provided to the downstream of a sponge ball collector in a sponge ball recycling pipeways for cleaning through the cooling pipes of a condenser. Electrical current is supplied by way of a variable resister to the electrodes and copper ions resulted from the dissolution of the electrodes are fed in the pipes to kill the marine livings such as barnacles and prevent the marine livings from depositing to the inside of the sponge ball recycling pipeways. (Seki, T.)

  15. Muonic Chemistry in Condensed Matter

    CERN Multimedia

    2002-01-01

    When polarized muons (@m|+) stop in condensed matter, muonic atoms are formed in the final part of their range, and direct measurements of the @m|+-spin polarization are possible via the asymmetric decay into positrons. The hyperfine interaction determines the characteristic precession frequencies of the @m|+ spin in muonium, @w(Mu). Such frequencies can be altered by the interactions of the muonium's electron spin with the surrounding medium. The measurement of @w(Mu) in a condensed system is known often to provide unique information regarding the system. \\\\ \\\\ In particular, the use of muonium atoms as a light isotope of the simple reactive radical H|0 allows the investigation of fast reactions of radicals over a typical time scale 10|-|9~@$<$~t~@$<$~10|-|5~sec, which is determined by the instrumental resolution at one end and by the @m|+ lifetime at the other. \\\\ \\\\ In biological macromolecules transient radicals, such as the constituents of DNA itself, exist on a time scale of sub-microseconds, acco...

  16. On scalar condensate baryogenesis model

    International Nuclear Information System (INIS)

    Kiriloval, D.P.; Valchanov, T.V.

    2004-09-01

    We discuss the scalar field condensate baryogenesis model, which is among the baryogenesis scenarios preferred today, compatible with inflation. According to that model a complex scalar field φ, carrying baryon charge B≠0 is generated at inflation. The baryon excess in the Universe results from the φ decay at later stages of Universe evolution (T 15 GeV). We updated the model's parameters range according to the current observational cosmological constraints and analyzed numerically φ evolution after the inflationary stage till its decay φ → qq-barlγ. During that period oscillated with a decreasing amplitude due to Universe expansion and particle production processes due to the coupling of the field to fermions gφf 1 f 2 . It was shown that particle creation processes play an essential role for evolution and its final value. It may lead to a considerable decrease of the field's amplitude for large g and/or large H values, which reflects finally into strong damping of the baryon charge carried by the condensate. The analysis suggests that for a natural range of the model's parameters the observed value of the baryon asymmetry can be obtained and the model can serve as a successful baryogenesis model, compatible with inflation. (author)

  17. Magnon condensation and spin superfluidity

    Science.gov (United States)

    Bunkov, Yury M.; Safonov, Vladimir L.

    2018-04-01

    We consider the Bose-Einstein condensation (BEC) of quasi-equilibrium magnons which leads to spin superfluidity, the coherent quantum transfer of magnetization in magnetic material. The critical conditions for excited magnon density in ferro- and antiferromagnets, bulk and thin films, are estimated and discussed. It was demonstrated that only the highly populated region of the spectrum is responsible for the emergence of any BEC. This finding substantially simplifies the BEC theoretical analysis and is surely to be used for simulations. It is shown that the conditions of magnon BEC in the perpendicular magnetized YIG thin film is fulfillied at small angle, when signals are treated as excited spin waves. We also predict that the magnon BEC should occur in the antiferromagnetic hematite at room temperature at much lower excited magnon density compared to that of ferromagnetic YIG. Bogoliubov's theory of Bose-Einstein condensate is generalized to the case of multi-particle interactions. The six-magnon repulsive interaction may be responsible for the BEC stability in ferro- and antiferromagnets where the four-magnon interaction is attractive.

  18. Creating nanoscale emulsions using condensation.

    Science.gov (United States)

    Guha, Ingrid F; Anand, Sushant; Varanasi, Kripa K

    2017-11-08

    Nanoscale emulsions are essential components in numerous products, ranging from processed foods to novel drug delivery systems. Existing emulsification methods rely either on the breakup of larger droplets or solvent exchange/inversion. Here we report a simple, scalable method of creating nanoscale water-in-oil emulsions by condensing water vapor onto a subcooled oil-surfactant solution. Our technique enables a bottom-up approach to forming small-scale emulsions. Nanoscale water droplets nucleate at the oil/air interface and spontaneously disperse within the oil, due to the spreading dynamics of oil on water. Oil-soluble surfactants stabilize the resulting emulsions. We find that the oil-surfactant concentration controls the spreading behavior of oil on water, as well as the peak size, polydispersity, and stability of the resulting emulsions. Using condensation, we form emulsions with peak radii around 100 nm and polydispersities around 10%. This emulsion formation technique may open different routes to creating emulsions, colloidal systems, and emulsion-based materials.

  19. Condensation induced water hammer safety

    International Nuclear Information System (INIS)

    Gintner, M.A.

    1997-01-01

    Condensation induced water hammer events in piping systems can cause catastrophic steam system failures which can result in equipment damage, personal injury, and even death. As an industry, we have learned to become accustomed to the ''banging'' that we often hear in our steam piping systems, and complacent in our actions to prevent it. It is unfortunate that lives are lost needlessly, as this type of water hammer event is preventable if one only applies some basic principles when operating and maintaining their steam systems. At the U. S. Department of Energy's Hanford Site where I work, there was one such accident that occurred in 1993 which took the life of a former co-worker and friend of mine. Hanford was established as part of the Manhattan Project during World War II. it is a 560 square mile complex located along the banks of the Columbia River in Southeastern Washington State. For almost 45 years, hanford's mission was to produce weapons grade plutonium for our nations defense programs. Today, Hanford no longer produces plutonium, but is focused on site clean-up and economic diversification. Hanford still uses steam for heating and processing activities, utilizing over 20 miles of piping distribution systems similar to those found in industry. Although these aging systems are still sound, they cannot stand up to the extreme pressure pulses developed by a condensation induced water hammer

  20. Condensation induced water hammer safety

    Energy Technology Data Exchange (ETDEWEB)

    Gintner, M.A.

    1997-03-10

    Condensation induced water hammer events in piping systems can cause catastrophic steam system failures which can result in equipment damage, personal injury, and even death. As an industry, we have learned to become accustomed to the ''banging'' that we often hear in our steam piping systems, and complacent in our actions to prevent it. It is unfortunate that lives are lost needlessly, as this type of water hammer event is preventable if one only applies some basic principles when operating and maintaining their steam systems. At the U. S. Department of Energy's Hanford Site where I work, there was one such accident that occurred in 1993 which took the life of a former co-worker and friend of mine. Hanford was established as part of the Manhattan Project during World War II. it is a 560 square mile complex located along the banks of the Columbia River in Southeastern Washington State. For almost 45 years, hanford's mission was to produce weapons grade plutonium for our nations defense programs. Today, Hanford no longer produces plutonium, but is focused on site clean-up and economic diversification. Hanford still uses steam for heating and processing activities, utilizing over 20 miles of piping distribution systems similar to those found in industry. Although these aging systems are still sound, they cannot stand up to the extreme pressure pulses developed by a condensation induced water hammer.

  1. Síntesis intermatricial y comparación de nanopartículas metálicas de Pd y Co soportadas en resinas catiónicas y aniónicas

    OpenAIRE

    Bastos Arrieta, Julio; Universitat Autònoma de Barcelona. Departament de Química

    2010-01-01

    Esta memoria de investigación es producto del trabajo experimental que se realizó con resinas de intercambio iónico para la síntesis intermatricial de nanopartículas metálicas de Co y Pd. Los estudios que se realizaron correspondieron a la iniciación en esta modalidad de síntesis de nanopartículas. En ellos se contemplaron las propiedades intrínsecas de la resina como: la capacidad de intercambio iónico, y funcionalidad química, tanto antes como después de la síntesis. Uno de los objetivos...

  2. Comparação dos valores de desgaste abrasivo e de microdureza de 13 resinas compostas usadas em odontologia através do método do disco retificado

    OpenAIRE

    Bianchi,Eduardo C.; Aguiar,Paulo R. de; Alves,Manoel C. S.; Freitas,César A. de; Rodrigues,Ana R.; Carvalho Jr.,Oscar B. de

    2007-01-01

    Atualmente tem-se buscado simplificar a tarefa de caracterização da vida útil de restaurações dentárias realizadas por resinas compostas através de métodos laboratoriais, que são mais rápidos e não sofrem influência de variáveis pessoais inerentes às análises clínicas. Com este propósito, este trabalho apresenta uma nova metodologia de ensaio laboratorial para a avaliação do desgaste abrasivo de resinas compostas através do método do disco retificado. Realizaram-se ensaios de resistência ao d...

  3. The physics of exciton-polariton condensates

    CERN Document Server

    Lagoudakis, Konstantinos

    2013-01-01

    In 2006 researchers created the first polariton Bose-Einstein condensate at 19K in the solid state. Being inherently open quantum systems, polariton condensates open a window into the unpredictable world of physics beyond the “fifth state of matter”: the limited lifetime of polaritons renders polariton condensates out-of-equilibrium and provides a fertile test-bed for non-equilibrium physics. This book presents an experimental investigation into exciting features arising from this non-equilibrium behavior. Through careful experimentation, the author demonstrates the ability of polaritons to synchronize and create a single energy delocalized condensate. Under certain disorder and excitation conditions the complete opposite case of coexisting spatially overlapping condensates may be observed. The author provides the first demonstration of quantized vortices in polariton condensates and the first observation of fractional vortices with full phase and amplitude characterization. Finally, this book investigate...

  4. Condensate from a two-stage gasifier

    DEFF Research Database (Denmark)

    Bentzen, Jens Dall; Henriksen, Ulrik Birk; Hindsgaul, Claus

    2000-01-01

    Condensate, produced when gas from downdraft biomass gasifier is cooled, contains organic compounds that inhibit nitrifiers. Treatment with activated carbon removes most of the organics and makes the condensate far less inhibitory. The condensate from an optimised two-stage gasifier is so clean...... that the organic compounds and the inhibition effect are very low even before treatment with activated carbon. The moderate inhibition effect relates to a high content of ammonia in the condensate. The nitrifiers become tolerant to the condensate after a few weeks of exposure. The level of organic compounds...... and the level of inhibition are so low that condensate from the optimised two-stage gasifier can be led to the public sewer....

  5. Bio-oil fractionation and condensation

    Science.gov (United States)

    Brown, Robert C; Jones, Samuel T; Pollard, Anthony

    2013-07-02

    A method of fractionating bio-oil vapors which involves providing bio-oil vapors comprising bio-oil constituents is described. The bio-oil vapors are cooled in a first stage which comprises a condenser having passages for the bio-oil separated by a heat conducting wall from passages for a coolant. The coolant in the condenser of the first stage is maintained at a substantially constant temperature, set at a temperature in the range of 75 to 100.degree. C., to condense a first liquid fraction of liquefied bio-oil constituents in the condenser of the first stage. The first liquid fraction of liquified bio-oil constituents from the condenser in the first stage is collected. Also described are steps for subsequently recovering further liquid fractions of liquefied bio-oil constituents. Particular compositions of bio-oil condensation products are also described.

  6. The Dynamics of Aerosols in Condensational Scrubbers

    DEFF Research Database (Denmark)

    Johannessen, Jens Tue; Christensen, Jan A.; Simonsen, Ole

    1997-01-01

    A mathematical model for the simulation of the dynamics of aerosol change in condensational scrubbers and scrubbing condensers is proposed. The model is applicable for packed column gas/liquid contact when plug flow can be assumed. The model is compared with experimental data for particle removal...... for their estimation is proposed. The behaviour of scrubbers and condensers for some important technical applications is demonstrated by model simulations. (C) 1997 Elsevier Science Ltd....

  7. Nonlinear behavior of the radiative condensation instability

    International Nuclear Information System (INIS)

    McCarthy, D.; Drake, J.F.

    1991-01-01

    An investigation of the nonlinear behavior of the radiative condensation instability is presented in a simple one-dimensional magnetized plasma. It is shown that the radiative condensation is typically a nonlinear instability---the growth of the instability is stronger once the disturbance reaches finite amplitude. Moreover, classical parallel thermal conduction is insufficient by itself to saturate the instability. Radiative collapse continues until the temperature in the high density condensation falls sufficiently to reduce the radiation rate

  8. Condensation on Superhydrophobic Copper Oxide Nanostructures

    OpenAIRE

    Enright, Ryan; Miljkovic, Nenad; Dou, Nicholas; Nam, Youngsuk; Wang, Evelyn N.

    2013-01-01

    Condensation is an important process in both emerging and traditional power generation and water desalination technologies. Superhydrophobic nanostructures promise enhanced condensation heat transfer by reducing the characteristic size of departing droplets via a surface-tension-driven mechanism [1]. In this work, we investigated a scalable synthesis technique to produce oxide nanostructures on copper surfaces capable of sustaining superhydrophobic condensation and characterized the growth an...

  9. Utilização de ligninas em resinas fenólicas: 1. Preparação de novolacas a partir de lignossulfonatos Use of lignins in phenolic resins: 1. Preparation of novolacs from lignosulfonates 49

    Directory of Open Access Journals (Sweden)

    Fernando dos Santos

    1999-01-01

    Full Text Available Este trabalho descreve uma utilização mais nobre para a lignina obtida de processos industriais de polpação. Foram preparadas resinas fenólicas tipo novolaca, utilizando-se lignossulfonato de amônio e lignossulfonato de sódio (com diferentes teores de açúcares residuais como correagentes, em substituição parcial ao fenol. As resinas foram preparadas mantendo-se o processo utilizado industrialmente. As resinas foram caracterizadas por análises químicas, quanto à distribuição de massa molar e análises térmicas. As resinas preparadas com lignossulfonatos apresentaram maior reatividade com hexametilenotetramina (agente de reticulação. Isto é uma vantagem, pois pode-se ter ciclos de moldagem de peças mais curtos, o que economicamente é favorável.This work describes the production of high value products using lignins obtained from industrial pulping processes. Novolac phenolic resins were prepared employing ammonium lignosulfonates and sodium lignosulfonates (with different residual sugar contents in a partial replacement of phenol. The resins were prepared using the same conditions employed in the industrial phenolic resins production. The lignin based resins were characterized by chemical analysis, molecular weight distribution and thermal analysis. The resins prepared using lignosulfonates showed higher reactivity with hexamethylenetetramine (crosslink agent. This behavior lead to another economic advantage as consequence of the reduction in the expended time for molding cycles.

  10. Influence of different kinds of rosins and hydrogenated resins on the setting time of Grossman cements Influência de diferentes tipos de breus e resinas hidrogenadas sobre o tempo de endurecimento dos cimentos do tipo Grossman

    Directory of Open Access Journals (Sweden)

    Manoel Damião SOUSA NETO

    1999-01-01

    Full Text Available In this study, the effect on the setting time by the addition of different kinds of rosin and hydrogenated resin on the Grossman cement powder was evaluated. The experiments were carried out following the American Dental Association’s specification number 57 for root canal sealers. For this analysis, different Grossman cement powders were prepared using different rosins (X, WW and WG and hydrogenated resins (Staybelite and Staybelite ester 10. The study of the physicochemical properties of the Grossman cements obtained the different kinds of rosins and hydrogenated resins interference on the cement’s setting time. The hydrogenated resin, having a higher pH, increased the setting time of the cement when compared to the X, WW and WG rosins.No presente estudo, analisou-se o efeito da adição de diferentes tipos de breus e resinas hidrogenadas ao pó do cimento de GROSSMAN sobre o tempo de endurecimento. Os experimentos foram realizados de acordo com a Especificação 57 para materiais obturadores de canais radiculares da American Dental Association (ADA. Para análise, foram aviados pós do cimento de GROSSMAN com diferentes tipos de breu (X, WW e WG e resinas hidrogenadas (Stabylite e Stabylite éster 10. Os estudos das propriedades físico-químicas dos cimentos tipo GROSSMAN obtidos de diferentes tipos de breus e resinas hidrogenadas interferem no tempo de endurecimento do cimento. A resina hidrogenada, obtida do processo de hidrogenação tem o pH mais alto, provocando um aumento do tempo de endurecimento do cimento em relação aos breus tipo X, WW e WG, que têm pH mais ácido.

  11. Relationship between filler content and selected mechanical properties of six microhybrid composites = Relação entre o conteúdo de carga e propriedades mecânicas de seis resinas compostas microhíbridas

    Directory of Open Access Journals (Sweden)

    Mota, Eduardo Gonçalves

    2011-01-01

    Conclusão: A resina Z2 teve a maior resistência à compressão; Z2 e TC apresentaram maiores módulo de elasticidade, VHN e conteúdo de carga em peso. O conteúdo de carga em peso teve uma forte influência nas propriedades mecânicas avaliadas (0,78

  12. Resistência à compressão entre uma resina composta direta e dois cerômeros = Resistence of compression between a direct composite resin and two “cerômeros”

    Directory of Open Access Journals (Sweden)

    Gouvêa, Cresus Vinícius Depes de

    2007-01-01

    Full Text Available Esse estudo avaliou a resistência à fratura de duas resinas laboratoriais que se encontram no mercado, a Artglass® e a Targis® e como grupo comparador, a resina composta direta TPH®. Foram utilizados cinco corpos de prova de cada resina a ser testada. Com o auxílio de matrizes em aço inoxidável com forma de um cone segmentado, com medidas internas de 8,0 mm de diâmetro na base, 9,0 mm na porção superior e 4,0 mm de altura, foram confeccionados os corpos de prova. As amostras foram mantidas em água destilada por 72 horas e submetidas a uma carga axial por ação de uma ponta de extremidade arredondada de 2 mm diâmetro, adaptada a uma máquina de teste universal EMIC 500. A velocidade foi de 0,5 mm/min, com uma célula de capacidade de carga de 200 kgf. A carga e o ponto de fratura foram registrados na máquina. As médias foram calculadas em kgf, sendo o Artglass® apresentando A = 223,46; Targis® T = 204,13; TPH® Tp = 98,26. Os dados foram submetidos à análise estatística. Observou-se que a resina TPH obteve significativamente menor resistência à compressão enquanto Targis e Artiglass não apresentaram diferença estaticamente significativamente entre si; o conteúdo de carga inorgânica influencia positivamente na resistência à compressão

  13. Strangeness condensation and ''clearing'' of the vacuum

    International Nuclear Information System (INIS)

    Brown, G.E.; Kubodera, Kuniharu; Rho, M.; State Univ. of New York, Stony Brook

    1987-01-01

    We show that a substantial amount of strange quark-antiquark pair condensates in the nucleon required by the πN sigma term implies that kaons could condense in nuclear matter at a density about three times that of normal nuclear matter. This phenomenon can be understood as the ''cleansing'' of qanti q condensates from the QCD vacuum by a dense nuclear matter, resulting in a (partial) restoration of the chiral symmetry explicitly broken in the vacuum. It is suggested that the condensation signals a new phase distinct from that of quark plasma and that of ordinary dense hadronic matter. (orig.)

  14. Advances in modelling of condensation phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Liu, W.S.; Zaltsgendler, E. [Ontario Hydro Nuclear, Toronto (Canada); Hanna, B. [Atomic Energy of Canada Limited, Pinawa, Manitoba (Canada)

    1997-07-01

    The physical parameters in the modelling of condensation phenomena in the CANDU reactor system codes are discussed. The experimental programs used for thermal-hydraulic code validation in the Canadian nuclear industry are briefly described. The modelling of vapour generation and in particular condensation plays a key role in modelling of postulated reactor transients. The condensation models adopted in the current state-of-the-art two-fluid CANDU reactor thermal-hydraulic system codes (CATHENA and TUF) are described. As examples of the modelling challenges faced, the simulation of a cold water injection experiment by CATHENA and the simulation of a condensation induced water hammer experiment by TUF are described.

  15. Advances in modelling of condensation phenomena

    International Nuclear Information System (INIS)

    Liu, W.S.; Zaltsgendler, E.; Hanna, B.

    1997-01-01

    The physical parameters in the modelling of condensation phenomena in the CANDU reactor system codes are discussed. The experimental programs used for thermal-hydraulic code validation in the Canadian nuclear industry are briefly described. The modelling of vapour generation and in particular condensation plays a key role in modelling of postulated reactor transients. The condensation models adopted in the current state-of-the-art two-fluid CANDU reactor thermal-hydraulic system codes (CATHENA and TUF) are described. As examples of the modelling challenges faced, the simulation of a cold water injection experiment by CATHENA and the simulation of a condensation induced water hammer experiment by TUF are described

  16. TRATAMENTO DA CASCA DE QUEIJO CANASTRA COM RESINA E SEUS EFEITOS DURANTE A MATURAÇÃO E NA QUALIDADE COMO FORMA DE MELHORAR O ASPECTO E AGREGAR VALOR AO PRODUTO

    Directory of Open Access Journals (Sweden)

    Paulo Henrique Costa Paiva

    2012-08-01

    Full Text Available O principal objetivo deste trabalho foi testar uma alternativa para melhorar o aspecto de apresentação e a qualidade do queijo Minas artesanal da Canastra sem comprometer as suas características peculiares. Assim, foram comparados queijos Minas artesanais da Canastra ao longo da maturação com aplicação de resina de grau alimentar na casca em relação àqueles sem aplicação, quanto aos aspectos físico-químicos, microbiológicos e sensoriais, durante as quatro estações do ano. Nos ensaios preliminares foram definidas a forma de aplicação (emprego das mãos e a quantidade (5 g de resina pura/unidade de queijo, sem necessidade da adição de sorbato de potássio. Durante o período de maturação estudado (2, 15, 30 e 45 dias não observou-se diferença significativa entre os queijos com e sem aplicação de resina na casca em relação às características físico-químicas como pH, atividade de água, teor de umidade, teor de gordura no extrato seco, extensão e profundidade de proteólise. E aos 15 e 30 dias de maturação, a Análise Descritiva Quantitativa Modificada (ADQM não indicou diferença entre os tratamentos com e sem aplicação de resina quanto aos atributos sensoriais avaliados, exceto para o aspecto global após 15 dias. Os queijos com aplicação de resina na casca tiveram um escore referente ao aspecto global maior em relação àqueles sem aplicação, após 15 dias de maturação, devido ao menor crescimento de mofos durante esse período. A partir dos escores obtidos no teste de aceitação mediante o uso de escala hedônica de 9 pontos, também não houve diferença significativa entre os queijos com e sem aplicação de resina na casca durante as quatro estações do ano. Entretanto, observou-se diferenças significativas nos queijos ao longo do ano, em relação às características físico-químicas pH, teor de gordura no extrato seco e profundidade de proteólise, e em relação aos atributos sensoriais

  17. Produção de chapas de partículas orientadas “OSB” de Eucalyptus grandis com diferentes teores de resina, parafina e composição em camadas.

    Directory of Open Access Journals (Sweden)

    Setsuo Ivakiri

    2010-08-01

    Full Text Available Este trabalho foi desenvolvido com o objetivo de avaliar a influência dos seguintes parâmetros de processo de produção sobre as propriedades das chapas "OSB": composição das chapas em camadas cruzadas com proporções face-miolo-face de 30-40-30 e 20-60-20 em relação à composição homogênea; e, quantidades de 3, 4,5 e 6,0% de resina fenol-formaldeído, com incorporação de 0,5 e 1,0% de emulsão de parafina. Os resultados demonstraram que a composição das chapas, com a relação 20-60-20, apresentou melhor balanço das propriedades de flexão estática entre os sentidos de ensaios paralelo e perpendicular ao plano da chapa. A quantidade de 6,0% de resina foi a que resultou em melhores propriedades físico-mecânicas das chapas "OSB". A produção de chapas "OSB" de Eucalyptus grandis, com 4,5 e 6,0% de resina fenol-formaldeído, superou as exigências mínimas de propriedades mecânicas das chapas "OSB" referendadas pela norma canadense CSA 0437-0 (1993.

  18. RECICLAGEM DE PLACAS DE CIRCUITO IMPRESSO DE COMPUTADORES SUCATADOS PARA A RECUPERAÇÃO DE ESTANHO POR ELETROELUIÇÃO DE RESINAS POLIMÉRICAS DE TROCA IÔNICA

    Directory of Open Access Journals (Sweden)

    Afonso Henriques Martins

    2014-08-01

    Full Text Available Este trabalho apresenta os resultados experimentais para a recuperação de estanho presente em soluções aquosas a parir da reciclagem de computadores sucatados, através da técnica de eletroeluição de resina polimérica catiônica Amberlite IR-120®(Merck, USA. A resina foi carregada pela passagem de 200ml de solução aquosa 0,2g/l de Sn em 2,18N H2SO4 (concentração do licor de lixiviação de placas de circuito impresso-PCI de microcomputadores sucatados através do leito de 10g de resina. A realização dos experimentos foi baseada em um planejamento estatístico pelo método fatorial completo replicado de três variáveis a dois níveis. A otimização foi feita pelo método do passo ascendente. As condições consideradas ótimas visando a eletrorrecuperação de estanho foram 150A/m2 de densidade de corrente catódica, tempo de eletroeluição de 45 minutos e intensidade de agitação moderada do eletrólito (100rpm.

  19. ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT: NEW CONDENSATOR, INC.--THE CONDENSATOR DIESEL ENGINE RETROFIT CRANKCASE VENTILATION SYSTEM

    Science.gov (United States)

    EPA's Environmental Technology Verification Program has tested New Condensator Inc.'s Condensator Diesel Engine Retrofit Crankcase Ventilation System. Brake specific fuel consumption (BSFC), the ratio of engine fuel consumption to the engine power output, was evaluated for engine...

  20. Condensate subcooling near tube exit during horizontal in-tube condensation

    International Nuclear Information System (INIS)

    Hashizume, K.; Abe, N.; Ozeki, T.

    1992-01-01

    In-tube condensation is encountered in various applications for heat exchangers, such as domestic air-conditioning equipment, industrial air-cooled condensers, and moisture separator reheaters (MSRs) for nuclear power pants. Numerous research work has been conducted to predict the condensation heat transfer coefficient, and we have now enough information for thermal design of heat exchangers with horizontal in-tube condensation. Most of the research is analytical and/or experimental work in the annular or stratified flow regime, or experimental work on bulk condensation, i.e., from saturated vapor to complete condensation. On the other hand, there exist few data about the heat transfer phenomena in the very lower-quality region near the tube exit. The purpose of this paper is to clarify the condensation heat transfer phenomena near the tube exit experimentally and analytically, and to predict the degree of condensate subcooling

  1. Possibility of removing condensate and scattered oil from gas-condensate field during bed flooding

    Energy Technology Data Exchange (ETDEWEB)

    Belkina, N.A.; Yagubov, M.S.

    1984-01-01

    The problem is set of evaluating the possible removal from the bed of scattered oil and condensate during flooding of the bed. For this purpose, an experimental study was made of the displacement by water from the porous medium of the oil and condensate saturating it. The obtained experimental results permit evaluation of the possible removal from the gas-condensate bed of scattered oil and condensate during flooding of the bed.

  2. Gas manufacture, processes for: condensers

    Energy Technology Data Exchange (ETDEWEB)

    Young, W

    1876-11-29

    In the production of illuminating gas from coal, shale, hydrocarbon oil, or other substance used in the production of gas, the volatile products inside the retort are agitated by means of moving pistons or jets of compressed gas, steam, or vapor in order to decompose them into permanent gases, and in some cases to increase the volume of gas by the decomposition of the injected gas, etc. or by blending or carburetting this gas with the decomposition products of the volatile matters. To separate the condensible hydrocarbons from the crude gas it is passed through heated narrow tortuous passages or is caused to impinge on surfaces. If the crude gases are cold these surfaces are heated and vice versa.

  3. Quasiparticles in condensed matter systems

    Science.gov (United States)

    Wölfle, Peter

    2018-03-01

    Quasiparticles are a powerful concept of condensed matter quantum theory. In this review, the appearence and the properties of quasiparticles are presented in a unifying perspective. The principles behind the existence of quasiparticle excitations in both quantum disordered and ordered phases of fermionic and bosonic systems are discussed. The lifetime of quasiparticles is considered in particular near a continuous classical or quantum phase transition, when the nature of quasiparticles on both sides of a transition into an ordered state changes. A new concept of critical quasiparticles near a quantum critical point is introduced, and applied to quantum phase transitions in heavy fermion metals. Fractional quasiparticles in systems of restricted dimensionality are reviewed. Dirac quasiparticles emerging in so-called Dirac materials are discussed. The more recent discoveries of topologically protected chiral quasiparticles in topological matter and Majorana quasiparticles in topological superconductors are briefly reviewed.

  4. Characteristic aspects of pion-condensed phases

    International Nuclear Information System (INIS)

    Takatsuka, Tatsuyuki; Tamagaki, Ryozo; Tatsumi, Toshitaka.

    1993-01-01

    Characteristic aspects of pion-condensed phases are described in a simple model, for the system involving only nucleons and pions which interact through the π-N P-wave interaction. We consider one typical version in each of three kinds of pion condensation; the one of neutral pions (π 0 ), the one of charged pions (π C ) and the combined one in which both the π 0 and π C condensations are coexistent. Emphasis is put on the description to clarify the novel structures of the nucleon system which are realized in the pion-condensed phases. At first, it is shown that the π 0 condensation is equivalent to the particular nucleonic phase realized by a structure change of the nucleon system, where the attractive first-order effect of the one-pion-exchange (OPE) tensor force is brought about coherently. The aspects of this phase are characterized by the layered structure with a specific spin-isospin order with one-dimensional localization (named the ALS structure in short), which provides the source function for the condensed π 0 field. We utilize both descriptions with use of fields and potentials for the π 0 condensation. Next, the π C condensation realized in neutron-rich matter is described by adopting a version of the traveling condensed wave. In this phase, the nucleonic structure becomes the Fermi gas consisting of quasi-neutrons described by a superposition of neutron and proton. In this sense the structure change of the nucleon system for the π C condensation is moderate, and the field description is suitable. Finally, we describe a coexistent pion condensation, in which both the π 0 and π C condensations coexist without interference in such a manner that the π C condensation develops in the ALS structure. The model adopted here provides us with the characteristic aspects of the pion-condensed phases persisting in the realistic situation, where other ingredients affecting the pion condensation are taken into account. (author)

  5. Statistical physics and condensed matter

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    This document is divided into 4 sections: 1) General aspects of statistical physics. The themes include: possible geometrical structures of thermodynamics, the thermodynamical foundation of quantum measurement, transport phenomena (kinetic theory, hydrodynamics and turbulence) and out of equilibrium systems (stochastic dynamics and turbulence). The techniques involved here are typical of applied analysis: stability criteria, mode decomposition, shocks and stochastic equations. 2) Disordered, glassy and granular systems: statics and dynamics. The complexity of the systems can be studied through the structure of their phase space. The geometry of this phase space is studied in several works: the overlap distribution can now be computed with a very high precision; the boundary energy between low lying states does not behave like in ordinary systems; and the Edward's hypothesis of equi-probability of low lying metastable states is invalidated. The phenomenon of aging, characteristic of glassy dynamics, is studied in several models. Dynamics of biological systems or of fracture is shown to bear some resemblance with that of disordered systems. 3) Quantum systems. The themes include: mesoscopic superconductors, supersymmetric approach to strongly correlated electrons, quantum criticality and heavy fermion compounds, optical sum rule violation in the cuprates, heat capacity of lattice spin models from high-temperature series expansion, Lieb-Schultz-Mattis theorem in dimension larger than one, quantum Hall effect, Bose-Einstein condensation and multiple-spin exchange model on the triangular lattice. 4) Soft condensed matter and biological systems. Path integral representations are invaluable to describe polymers, proteins and self-avoiding membranes. Using these methods, problems as diverse as the titration of a weak poly-acid by a strong base, the denaturation transition of DNA or bridge-hopping in conducting polymers have been addressed. The problems of RNA folding

  6. Statistical physics and condensed matter

    International Nuclear Information System (INIS)

    2003-01-01

    This document is divided into 4 sections: 1) General aspects of statistical physics. The themes include: possible geometrical structures of thermodynamics, the thermodynamical foundation of quantum measurement, transport phenomena (kinetic theory, hydrodynamics and turbulence) and out of equilibrium systems (stochastic dynamics and turbulence). The techniques involved here are typical of applied analysis: stability criteria, mode decomposition, shocks and stochastic equations. 2) Disordered, glassy and granular systems: statics and dynamics. The complexity of the systems can be studied through the structure of their phase space. The geometry of this phase space is studied in several works: the overlap distribution can now be computed with a very high precision; the boundary energy between low lying states does not behave like in ordinary systems; and the Edward's hypothesis of equi-probability of low lying metastable states is invalidated. The phenomenon of aging, characteristic of glassy dynamics, is studied in several models. Dynamics of biological systems or of fracture is shown to bear some resemblance with that of disordered systems. 3) Quantum systems. The themes include: mesoscopic superconductors, supersymmetric approach to strongly correlated electrons, quantum criticality and heavy fermion compounds, optical sum rule violation in the cuprates, heat capacity of lattice spin models from high-temperature series expansion, Lieb-Schultz-Mattis theorem in dimension larger than one, quantum Hall effect, Bose-Einstein condensation and multiple-spin exchange model on the triangular lattice. 4) Soft condensed matter and biological systems. Path integral representations are invaluable to describe polymers, proteins and self-avoiding membranes. Using these methods, problems as diverse as the titration of a weak poly-acid by a strong base, the denaturation transition of DNA or bridge-hopping in conducting polymers have been addressed. The problems of RNA folding has

  7. Demonstration of Nautilus Centripetal Capillary Condenser Technology

    Science.gov (United States)

    Wheeler, RIchard; Tang, Linh; Wambolt, Spencer; Golliher, Eric; Agui, Juan

    2016-01-01

    This paper describes the results of a proof of concept effort for development of a Nautilus Centripetal Capillary Condenser (NCCC or NC3) used for microgravity compatible water recovery from moist air with integral passive phase separation. Removal of liquid condensate from the air stream exiting a condenser is readily performed here on Earth. In order to perform this function in space however, without gravity or mechanical action, other tactics including utilization of inertial, drag and capillary forces are required. Within the NC3, liquid water forms via condensation on cold condenser surfaces as humid air passes along multiple spiral channels, each in its own plane, all together forming a stacked plate assembly. Non-mechanical inertial forces are employed to transfer condensate, as it forms, via centripetal action to the outer perimeter of each channel. A V-shaped groove, constructed on this outer edge of the spiral channel, increases local capillary forces thereby retaining the liquid. Air drag then pulls the liquid along to a collection region near the center of the device. Dry air produced by each parallel spiral channel is combined in a common orthogonal, out-of-plane conduit passing down the axial center of the stacked device. Similarly, the parallel condensate streams are combined and removed from the condenser/separator through yet another out-of-plane axial conduit. NC3 is an integration of conventional finned condenser operation, combined with static phase separation and capillary transport phenomena. A Mars' transit mission would be a logical application for this technology where gravity is absent and the use of vibrating, energy-intensive, motor-driven centrifugal separators is undesired. Here a vapor stream from either the Heat Melt Compactor or the Carbon dioxide Reduction Assembly, for example, would be dried to a dew point of 10 deg using a passive NC3 condenser/separator with the precious water condensate recycled to the water bus.

  8. Comparison of Heat Transfer Coefficients of Silver Coated and Chromium Coated Copper Tubes of Condenser in Dropwise Condensation

    OpenAIRE

    Er. Shivesh Kumar; Dr. Amit Kumar

    2016-01-01

    Since centuries steam is being used in power generating system. The steam leaving the power unit is reconverted into water in a condenser designed to transfer heat from the steam to the cooling water as rapidly and as efficiently as possible. The efficiency of condenser depends on rate of condensation and mode of condensation of steam in the condenser. The increase in efficiency of the condenser enhances the heat transfer co-efficient which in turn results in economic design of condenser and ...

  9. Condensate growth in trapped Bose gates

    NARCIS (Netherlands)

    Bijlsma, M.J.; Zaremba, E.; Stoof, H.T.C.

    2000-01-01

    We study the dynamics of condensate fromation in an inhomogeneous trapped Bose gas with a positive interatomic scattering length. We take into account both the nonequilibrium kinetics of the thermal cloud and the Hartree-Fock mean-field efects in the condensed and the noncondensed parts of the gas.

  10. Condensate growth in trapped Bose gases

    NARCIS (Netherlands)

    Bijlsma, M.J.; Zaremba, E.; Stoof, H.T.C.

    2000-01-01

    We study the dynamics of condensate formation in an inhomogeneous trapped Bose gas with a positive interatomic scattering length. We take into account both the nonequilibrium kinetics of the thermal cloud and the Hartree-Fock mean-field effects in the condensed and the noncondensed parts of the gas.

  11. Bosonization with inclusion of the gluon condensate

    International Nuclear Information System (INIS)

    Ebert, D.; Volkov, M.K.

    1994-01-01

    The effects of the gluon condensate on the quark condensate and on masses and coupling constants of composite mesons are discussed within a QCD-motivated Nambu-Jona-Lasinio model for zero temperature as well as for the case of finite temperature and baryon number density. (orig.)

  12. Collision of Bose Condensate Dark Matter structures

    International Nuclear Information System (INIS)

    Guzman, F. S.

    2008-01-01

    The status of the scalar field or Bose condensate dark matter model is presented. Results about the solitonic behavior in collision of structures is presented as a possible explanation to the recent-possibly-solitonic behavior in the bullet cluster merger. Some estimates about the possibility to simulate the bullet cluster under the Bose Condensate dark matter model are indicated.

  13. Soliton resonance in bose-einstein condensate

    Science.gov (United States)

    Zak, Michail; Kulikov, I.

    2002-01-01

    A new phenomenon in nonlinear dispersive systems, including a Bose-Einstein Condensate (BEC), has been described. It is based upon a resonance between an externally induced soliton and 'eigen-solitons' of the homogeneous cubic Schrodinger equation. There have been shown that a moving source of positive /negative potential induces bright /dark solitons in an attractive / repulsive Bose condensate.

  14. Born-Kothari Condensation for Fermions

    Directory of Open Access Journals (Sweden)

    Arnab Ghosh

    2017-09-01

    Full Text Available In the spirit of Bose–Einstein condensation, we present a detailed account of the statistical description of the condensation phenomena for a Fermi–Dirac gas following the works of Born and Kothari. For bosons, while the condensed phase below a certain critical temperature, permits macroscopic occupation at the lowest energy single particle state, for fermions, due to Pauli exclusion principle, the condensed phase occurs only in the form of a single occupancy dense modes at the highest energy state. In spite of these rudimentary differences, our recent findings [Ghosh and Ray, 2017] identify the foregoing phenomenon as condensation-like coherence among fermions in an analogous way to Bose–Einstein condensate which is collectively described by a coherent matter wave. To reach the above conclusion, we employ the close relationship between the statistical methods of bosonic and fermionic fields pioneered by Cahill and Glauber. In addition to our previous results, we described in this mini-review that the highest momentum (energy for individual fermions, prerequisite for the condensation process, can be specified in terms of the natural length and energy scales of the problem. The existence of such condensed phases, which are of obvious significance in the context of elementary particles, have also been scrutinized.

  15. Hydrophilic structures for condensation management in appliances

    Science.gov (United States)

    Kuehl, Steven John; Vonderhaar, John J.; Wu, Guolian; Wu, Mianxue

    2016-02-02

    An appliance that includes a cabinet having an exterior surface; a refrigeration compartment located within the cabinet; and a hydrophilic structure disposed on the exterior surface. The hydrophilic structure is configured to spread condensation. The appliance further includes a wicking structure located in proximity to the hydrophilic structure, and the wicking structure is configured to receive the condensation.

  16. Análise de peças anatômicas preservadas com resina de poliester para estudo em anatomia humana Analysis of anatomical pieces preservation with polyester resin for human anatomy study

    Directory of Open Access Journals (Sweden)

    Ítalo Martins de Oliveira

    2013-02-01

    Full Text Available OBJETIVO: avaliar o uso da resina de poliéster na preservação de peças anatômicas para estudo da anatomia humana. MÉTODOS: foram utilizadas 150 peças anatômicas, sendo as mesmas não fixadas (frescas, fixadas em formol a 10% e moldes vasculares de órgãos injetados com acetato de vinil e a resina de poliéster. A solução utilizada foi composta de resina de poliéster com seu diluente monômero de estireno e catalisador (peroxol. Foram obtidos, após a inclusão nesta solução, modelos em resina transparente, que permitiam a plena observação das estruturas e conservação da peça utilizada. RESULTADOS: na avaliação das peças, foi observado grau de extrema transparência, promovendo uma completa visualização das estruturas com a perfeita preservação da anatomia. A duração média para a completa finalização da inclusão foi 48 horas. Apenas 14 peças (9,3% foram inutilizadas durante o preparo. CONCLUSÃO: a resina de poliéster pode ser utilizada para a preservação de peças anatômicas para o ensino da anatomia humana, de maneira prática, estética e duradoura.OBJECTIVE: To evaluate the use of polyester resin in preserving anatomical specimens for the study of human anatomy. METHODS: We used 150 anatomical specimens, comprised of unfixed (fresh, fixed in 10% formalin and vascular casts of organs injected with vinyl acetate and polyester resin. The solution used consisted of polyester resin with the diluent styrene monomer and catalyst (peroxol. After embedding in this solution, models in transparent resin were obtained, allowing full observation of structures and conservation of the specimens used. RESULTS: upon evaluation of the specimens, we observed a high degree of transparency, which promoted a complete visualization of structures with perfect preservation of the anatomy. The average time for the completion of the embedding was 48 hours. Only 14 specimens (9.3% were lost during the preparation. CONCLUSION

  17. Titanium application to power plant condensers

    International Nuclear Information System (INIS)

    Itoh, H.

    1987-01-01

    Recently, the growth of operating performance and construction plan of titanium-tubed condensers in thermal and unclear power plants has been very impressive. High-quality, thinner welded titanium tubes used for cooling tubes, matching design specifications of condensers, have been stably supplied through mass production. It now can be said that various technical problems for titanium-tubed condensers have been solved, but data on operating performance in large-scale commercial plants are still scarce, and site-by-site information needs be exchanged more frequently and on a larger scale. Projects to replace existing condenser cooling tubes with those of corrosion-resistant titanium have been actively furthered, with the only remaining barrier to full employment being cost effectiveness. It is hoped that condenser and tube manufacturers will conduct more joint value analyses

  18. Capillary Condensation in 8 nm Deep Channels.

    Science.gov (United States)

    Zhong, Junjie; Riordon, Jason; Zandavi, Seyed Hadi; Xu, Yi; Persad, Aaron H; Mostowfi, Farshid; Sinton, David

    2018-02-01

    Condensation on the nanoscale is essential to understand many natural and synthetic systems relevant to water, air, and energy. Despite its importance, the underlying physics of condensation initiation and propagation remain largely unknown at sub-10 nm, mainly due to the challenges of controlling and probing such small systems. Here we study the condensation of n-propane down to 8 nm confinement in a nanofluidic system, distinct from previous studies at ∼100 nm. The condensation initiates significantly earlier in the 8 nm channels, and it initiates from the entrance, in contrast to channels just 10 times larger. The condensate propagation is observed to be governed by two liquid-vapor interfaces with an interplay between film and bridging effects. We model the experimental results using classical theories and find good agreement, demonstrating that this 8 nm nonpolar fluid system can be treated as a continuum from a thermodynamic perspective, despite having only 10-20 molecular layers.

  19. Complejación de la resina de intercambio de iones: enmascaramiento del sabor amargo de cefuroxime acetil Ion-exchange resin complexation: Masking the bitter taste of cefuroxime axetil

    Directory of Open Access Journals (Sweden)

    Inderbir Singh

    2011-06-01

    Full Text Available OBJECTIVE: the purpose of this research was to formulate taste masked complexes of cefuroxime axetil and to evaluate them for taste, drug loading and characterized by FTIR, XRD. Tablets were formulated of selected batches and evaluated for drug release and physical parameters. METHODS: complexation technique is used to prepare complexes of drug where ion exchange resins such as Indion® 214, Indion® 234 and Indion® 414 were used with a drug-resin ratio of 1:0.5, 1:1, 1:2. The drug resinates were characterized by Infrared Spectroscopy, DSC and X-Ray Diffraction pattern and evaluated for drug loading and taste. Direct compression method was used to formulate tablets. In vitro dissolution was carried out using USP II apparatus. RESULT: potential taste masking increased with increasing concentration of resin. Indion® 214 resin showed better taste masking effect as compared to Indion® 234 and Indion® 414. Percent of drug loading was maximum at drug : resin ratio of 1:1, after that it decreased. Prolonged (upto 5 h and slow drug release was observed with resin 214 at higher concentration. CONCLUSIONS: out of three resins chosen, Indion® 214 at higher concentration exhibit excellent taste masking as well as sustained drug release action.OBJETIVO: el objetivo de esta investigación fue formular los complejos con sabor amargo de cefuroxime acetil y evaluarlos por sabor, carga medicamentosa y caracterización por FTIR, XRD. Las tabletas fueron formuladas a partir de lotes seleccionados y evaluados en busca de la liberación medicamentosa y parámetros físicos. MÉTODOS: la técnica de complejación se utilizó para preparar complejos farmacológicos donde las resinas de intercambio iónico como Indion® 214, Indion® 234 y el Indion® 414 se emplearon a una proporción resina-medicamento de 1:0.5, 1:1, 1:2. Los resinados medicamentosos fueron caracterizados mediante espectroscopia infrarroja, DSC y el patrón de difracción-rayos-X, y evaluados

  20. Retention of oral microorganisms on conventional and resin-modified glass-ionomer cements Retenção de microrganismos bucais em cimentos de ionômero de vidro convencionais e modificados por resina

    Directory of Open Access Journals (Sweden)

    Denise PEDRINI

    2001-09-01

    Full Text Available Secondary caries are a worldwide public and socioeconomic problem. The placement of restorations can lead to the development of environmental conditions favorable to microbial colonization, especially on the tooth/restoration interface, which is a predisposing factor for secondary caries. The aim of this study was to evaluate microbial retention on conventional (Chelon-Fil and Vidrion R and resin-modified (Vitremer and Fuji II LC glass-ionomer cements, in situ, using a hybrid composite resin (Z100 as a control. Twelve volunteers wore Hawley appliances with specimens made of all tested filling materials for 7 days. The specimens were then removed from the appliances and transferred to tubes containing 2.0 ml of Ringer-PRAS. Microorganisms from the samples were inoculated onto blood agar and Mitis Salivarius Bacitracin agar and incubated under anaerobiosis (90% N2, 10% CO2, at 37°C, for 10 and 2 days, respectively. The resin-modified glass-ionomer cements and the composite resin retained the same levels of microorganisms on their surfaces. The resin-modified glass-ionomers retained less mutans streptococci than the composite resin and conventional glass-ionomer cements. The conventional glass-ionomer cements retained less mutans streptococci than the composite resin, but that difference was not statistically significant.A cárie secundária representa problema de saúde pública e socioeconômico no mundo. A restauração de dentes acometidos por cárie pode criar condições favoráveis à proliferação microbiana na superfície do material restaurador ou na interface dente/restauração, criando ambiente propício para o estabelecimento de cárie secundária. O objetivo deste estudo foi avaliar a capacidade de retenção de placa bacteriana em cimentos de ionômero de vidro convencionais (Chelon-Fil e Vidrion R e modificados por resina (Vitremer e Fuji II LC e de resina composta híbrida (Z100, utilizada como controle. Nos testes de reten

  1. Measurement of liquid-liquid equilibria for condensate + glycol and condensate + glycol + water systems

    DEFF Research Database (Denmark)

    Riaz, Muhammad; Kontogeorgis, Georgios; Stenby, Erling Halfdan

    2011-01-01

    ,2-ethanediol (MEG) + condensate and MEG + water + condensate systems at temperatures from (275 to 323) K at atmospheric pressure. The condensate used in this work is a stabilized natural gas condensate from an offshore field in the North Sea. Compositional analysis of the natural gas condensate was carried out...... by gas chromatography, and detailed separation of individual condensate's components has been carried out. Approximately 85 peaks eluting before nonane were identified by their retention time. Peak areas were converted to mass fraction using 1-heptene as an internal standard. The components were divided...... into boiling range groups from hexane to nonane. Paraffinic (P), naphthenic (N), and aromatic (A) distributions were obtained for the boiling point fractions up to nonane. The average molar mass and the overall density of the condensate were measured experimentally. For the mutual solubility of MEG...

  2. Efeito da técnica de polimento na topografia de superfície e na transmitância da resina composta

    Directory of Open Access Journals (Sweden)

    Marina Moura de Azevedo Souza

    Full Text Available Introdução: Clinicamente, é comum observar os efeitos de estratificação de restaurações de compósito apenas após o polimento. Objetivo: Avaliar o efeito da técnica de polimento na transmitância de luz e na topografia de superfície de uma resina composta. Material e método: Amostras da resina Filtek Z-350 XT (cor A1E foram confeccionadas em matriz metálica. Uma das superfícies das amostras recebeu acabamento com brocas de 12 lâminas e polimento através de uma das seguintes técnicas: SL (Sof-Lex, EH (Enhance e DH (DHPro. Ausência de polimento foi usada como controle. Após o polimento, as amostras deviam apresentar espessura final de 1 mm. A transmitância de luz foi avaliada através do espectrofotômetro, sendo considerada apenas a luz no espectro visível. A topografia de superfície foi avaliada através de interferometria a laser, com os parâmetros Sdq (híbrido, St (amplitude máxima e As (média de picos e vales. Os dados (n=5 foram submetidos a ANOVA e teste SNK. O teste de correlação de Pearson correlacionou Sdq, St e Sa à transmitância (α=0,05. Resultado: Todos os sistemas de polimento aumentaram a transmitância de luz em relação ao controle, não havendo diferença entre estes. Apenas as amostras polidas com SL e DH apresentaram maiores valores de Sdq que o Controle. Já para os parâmetros St e Sa, EH mostrou menores valores que o controle. Sdq e St mostraram correlação significativa com transmitância. Conclusão: Todos os sistemas de polimento foram efetivos em aumentar a transmitância, sendo a redução dos valores Sdq e St relacionada a esta modificação.

  3. Prótese intra-ocular de resina acrílica em cães e gatos Acrylic resin intraocular prosthesis in dogs and cats

    Directory of Open Access Journals (Sweden)

    S.C. Rahal

    2000-08-01

    Full Text Available Foram atendidos no Hospital Veterinário da Faculdade de Medicina Veterinária e Zootecnia da Unesp - Campus de Botucatu, 11 animais (oito cães e três gatos, com alterações oftálmicas unilaterais graves que levaram à perda total da função ocular (protrusão de globo com injúria nervosa e estrutural, perfurações de córnea com perda de conteúdo intra-ocular e endoftalmites, entre outras. Os animais, com idades entre dois meses e 10 anos, foram submetidos à evisceração e posterior inclusão de esfera de resina acrílica (metilmetacrilato na capa córneo-escleral ou escleral. As esferas foram previamente confeccionadas e esterilizadas por autoclavagem. No pós-operatório foram utilizados antiinflamatórios e antibioticoterapia tópica combinada ou não a sistêmica. O período de observação variou de 2 meses a 3 anos e os aspectos avaliados foram secreção ocular, blefarospasmo, sinais de desconforto e estética. Obtiveram-se resultados satisfatórios em oito casos. Concluiu-se que a resina acrílica pode ser uma alternativa para uso como inclusão em cavidade anoftálmica.Eleven animals (eight dogs and three cats, aged between two months and ten years were referred to the Veterinary Hospital of Faculty of Veterinary Medicine and Animal Science - Unesp, Botucatu, Brazil. These animals presented severe unilateral ophthalmic changes that lead to a total loss of ocular function, such as prolapsed eyes with nervous and structural injury, corneal damage with loss of intraocular contents or endophthalmitis among others. They were submitted to evisceration followed by the insertion of an acrylic resin prosthesis (methylmethacrylate in the corneoscleral or scleral shell. The spheres were previously made and sterilized by autoclave. The postoperative medical therapy included topical and systemic broad-spectrum antibiotics for seven days and anti-inflammatory drugs. The follow-up time varied from two months to three years. The evaluated

  4. Condensing boiler applications in the process industry

    International Nuclear Information System (INIS)

    Chen, Qun; Finney, Karen; Li, Hanning; Zhang, Xiaohui; Zhou, Jue; Sharifi, Vida; Swithenbank, Jim

    2012-01-01

    Major challenging issues such as climate change, energy prices and fuel security have focussed the attention of process industries on their energy efficiency and opportunities for improvement. The main objective of this research study was to investigate technologies needed to exploit the large amount of low grade heat available from a flue gas condensing system through industrial condensing boilers. The technology and application of industrial condensing boilers in various heating systems were extensively reviewed. As the condensers require site-specific engineering design, a case study was carried out to investigate the feasibility (technically and economically) of applying condensing boilers in a large scale district heating system (40 MW). The study showed that by recovering the latent heat of water vapour in the flue gas through condensing boilers, the whole heating system could achieve significantly higher efficiency levels than conventional boilers. In addition to waste heat recovery, condensing boilers can also be optimised for emission abatement, especially for particle removal. Two technical barriers for the condensing boiler application are corrosion and return water temperatures. Highly corrosion-resistant material is required for condensing boiler manufacture. The thermal design of a 'case study' single pass shell-and-tube condensing heat exchanger/condenser showed that a considerable amount of thermal resistance was on the shell-side. Based on the case study calculations, approximately 4900 m 2 of total heat transfer area was required, if stainless steel was used as a construction material. If the heat transfer area was made of carbon steel, then polypropylene could be used as the corrosion-resistant coating material outside the tubes. The addition of polypropylene coating increased the tube wall thermal resistance, hence the required heat transfer area was approximately 5800 m 2 . Net Present Value (NPV) calculations showed that the choice of a carbon

  5. Topology and condensed matter physics

    CERN Document Server

    Mj, Mahan; Bandyopadhyay, Abhijit

    2017-01-01

    This book introduces aspects of topology and applications to problems in condensed matter physics. Basic topics in mathematics have been introduced in a form accessible to physicists, and the use of topology in quantum, statistical and solid state physics has been developed with an emphasis on pedagogy. The aim is to bridge the language barrier between physics and mathematics, as well as the different specializations in physics. Pitched at the level of a graduate student of physics, this book does not assume any additional knowledge of mathematics or physics. It is therefore suited for advanced postgraduate students as well. A collection of selected problems will help the reader learn the topics on one's own, and the broad range of topics covered will make the text a valuable resource for practising researchers in the field.  The book consists of two parts: one corresponds to developing the necessary mathematics and the other discusses applications to physical problems. The section on mathematics is a qui...

  6. Ice-condenser aerosol tests

    International Nuclear Information System (INIS)

    Ligotke, M.W.; Eschbach, E.J.; Winegardner, W.K.

    1991-09-01

    This report presents the results of an experimental investigation of aerosol particle transport and capture using a full-scale height and reduced-scale cross section test facility based on the design of the ice compartment of a pressurized water reactor (PWR) ice-condenser containment system. Results of 38 tests included thermal-hydraulic as well as aerosol particle data. Particle retention in the test section was greatly influenced by thermal-hydraulic and aerosol test parameters. Test-average decontamination factor (DF) ranged between 1.0 and 36 (retentions between ∼0 and 97.2%). The measured test-average particle retentions for tests without and with ice and steam ranged between DF = 1.0 and 2.2 and DF = 2.4 and 36, respectively. In order to apparent importance, parameters that caused particle retention in the test section in the presence of ice were steam mole fraction (SMF), noncondensible gas flow rate (residence time), particle solubility, and inlet particle size. Ice-basket section noncondensible flows greater than 0.1 m 3 /s resulted in stable thermal stratification whereas flows less than 0.1 m 3 /s resulted in thermal behavior termed meandering with frequent temperature crossovers between flow channels. 10 refs., 66 figs., 16 tabs

  7. Condensing embryology teaching: alternative perspectives

    Directory of Open Access Journals (Sweden)

    Hasan M

    2018-03-01

    Full Text Available Mohammad Hasan, Syed Maaz Tariq, Syed Ali Haider Department of MBBS, Jinnah Sindh Medical University, Karachi, PakistanWe read the article “Condensing embryology teaching for medical students: can it be taught in 2 hours?” by Kazzazi and Bartlett quite attentively. The authors were successful in mentioning an effective mode of teaching embryology. Embryology is indeed an important subject that forms the base for appreciating anatomy and has immense practical implementations in different parts of medicine, for example, in pediatrics and ENT surgery. However, it is often neglected and is only taught in preclinical years.1 The authors proposed a method for teaching embryology splendidly from their perspective; therefore, we felt the need to expand the discussion from the perspective of third-year medical students who have just completed their preclinical years. Hence, we would like to mention few limitations to this study as well.Authors’ replyFawz Kazzazi, Jonathan Bartlett School of Clinical Medicine, University of Cambridge, Cambridge, UKWe read with interest the response letter by Hasan et al. We must first commend the editor and journal on their great ability to unify the medical community and extend topics for debate internationally.View the original paper by Kazzazi and Bartlett.

  8. Emergency condensator for BWR type reactor

    International Nuclear Information System (INIS)

    Ubakai, Yoichi; Narumi, Yuichi; Sakata, Yuji.

    1992-01-01

    An emergency condensator is constituted with heat transfer pipes, a steam chamber, an upper pipe plate, a lower pipe plate and a condensate chamber. The upper pipe plate is secured by supports, and a steam pipe is connected to the upper pipe plate. A condensate pipeline and a incondensible gas vent pipe are disposed to the condensate chamber. Taking thermal expansion of the steam pipes and thermal expansion of the heat transfer pipes into consideration, the heat transfer pipe is made as an L-shaped pipe having a vertical portion and a horizontal portion so as to absorb each of the thermal expansion smoothly. The L-shaped heat transfer pipes are constituted as a bundle of pipes having the end portions thereof secured to the upper pipe plate and the lower pipe plate. The emergency condensator is disposed in a emergency condensator pool chamber. Cooling water in contact with the outer side of the L-shaped heat transfer pipes is the pool water in the pool chamber, and the condensator chamber is disposed in concrete walls of the pool chamber. With such a constitution, stress due to thermal expansion of the heat transfer pipes is mitigated, and heat transfer performance, earth quake resistance and maintenancability are improved. (I.N.)

  9. Direct contact condensation in packed beds

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yi; Klausner, James F.; Mei, Renwei; Knight, Jessica [Department of Mechanical and Aerospace Engineering, University of Florida, Gainesville, FL 32611 (United States)

    2006-12-15

    A diffusion driven desalination process was recently described where a very effective direct contact condenser with a packed bed is used to condense water vapor out of an air/vapor mixture. A laboratory scale direct contact condenser has been fabricated as a twin tower structure with two stages, co-current and countercurrent. Experiments have been operated in each stage with respective saturated air inlet temperatures of 36, 40 and 43{sup o}C. The temperature and humidity data have been collected at the inlet and exit of the packed bed for different water to air mass flow ratios that vary between 0 and 2.5. A one-dimensional model based on conservation principles has been developed, which predicts the variation of temperature, humidity, and condensation rate through the condenser stages. Agreement between the model and experiments is very good. It is observed that the countercurrent flow stage condensation effectiveness is significantly higher than that for the co-current stage. The condensation heat and mass transfer rates were found to decrease when water blockages occur within the packed bed. Using high-speed digital cinematography, it was observed that this problem can occur at any operating condition, and is dependent on the packing surface wetting characteristics. This observation is used to explain the requirement for two different empirical constants, depending on packing diameter, suggested by Onda for the air side mass transfer coefficient correlation. (author)

  10. Enhanced Evaporation and Condensation in Tubes

    Science.gov (United States)

    Honda, Hiroshi

    A state-of-the-art review of enhanced evaporation and condensation in horizontal microfin tubes and micro-channels that are used for air-conditioning and refrigeration applications is presented. The review covers the effects of flow pattern and geometrical parameters of the tubes on the heat transfer performance. Attention is paid to the effect of surface tension which leads to enhanced evaporation and condensation in the microfin tubes and micro-channels. A review of prior efforts to develop empirical correlations of the heat transfer coefficient and theoretical models for evaporation and condensation in the horizontal microfin tubes and micro-channels is also presented.

  11. Open string decoupling and tachyon condensation

    International Nuclear Information System (INIS)

    Chalmers, G.

    2001-01-01

    The amplitudes in perturbative open string theory are examined as functions of the tachyon condensate parameter. The boundary state formalism demonstrates the decoupling of the open string modes at the non-perturbative minima of the tachyon potential via a degeneration of open world-sheets and identifies an independence of the coupling constants g s and g YM at general values of the tachyon condensate. The closed sector is generated at the quantum level; it is also generated at the classical level through the condensation of the propagating open string modes on the D-brane degrees of freedom.

  12. Preoperational test report, primary ventilation condensate system

    Energy Technology Data Exchange (ETDEWEB)

    Clifton, F.T.

    1997-01-29

    Preoperational test report for Primary Ventilation Condensate System, Project W-030. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The system provides a collection point for condensate generated by the W-030 primary vent offgas cooling system serving tanks AYIOI, AY102, AZIOI, AZI02. The system is located inside a shielded ventilation equipment cell and consists of a condensate seal pot, sampling features, a drain line to existing Catch Tank 241-AZ-151, and a cell sump jet pump. The tests verify correct system operation and correct indications displayed by the central Monitor and Control System.

  13. Active condensation of water by plants

    Directory of Open Access Journals (Sweden)

    Prokhorov Alexey Anatolievich

    2013-10-01

    Full Text Available This paper is devoted to some peculiarities of water condensation on the surface of plants . Arguments in support of the hypothesis that in decreasing temperature of leaves and shoots below the dew point, the plant can actively condense moisture from the air, increasing the duration of dewfall are presented. Evening dewfall on plant surfaces begins before starting the formation of fog. Morning condensation continues for some time after the air temperature exceeds the dew point . The phenomenon in question is found everywhere, but it is particularly important for plants in arid ecosystems.

  14. Biomolecular condensates: organizers of cellular biochemistry.

    Science.gov (United States)

    Banani, Salman F; Lee, Hyun O; Hyman, Anthony A; Rosen, Michael K

    2017-05-01

    Biomolecular condensates are micron-scale compartments in eukaryotic cells that lack surrounding membranes but function to concentrate proteins and nucleic acids. These condensates are involved in diverse processes, including RNA metabolism, ribosome biogenesis, the DNA damage response and signal transduction. Recent studies have shown that liquid-liquid phase separation driven by multivalent macromolecular interactions is an important organizing principle for biomolecular condensates. With this physical framework, it is now possible to explain how the assembly, composition, physical properties and biochemical and cellular functions of these important structures are regulated.

  15. Model of a chromomagnetic condensate in QCD

    International Nuclear Information System (INIS)

    Vladimirsky, V.V.

    1996-01-01

    The simplest form of the effective Lagrangian of a gluon field leads to a deep degeneracy of a magnetic condensate that arises when the stability of the standard perturbative vacuum is violated by quantum effects. The inclusion of terms in the effective Lagrangian that conserve color and Lorentz invariance enables the possible types of Abelian and non-Abelian condensate fields to be classified. The degeneracy is partially removed. One of the four types of the condensate permits the emergence of closed vortex lines that correspond to cyclic permutations of colors upon circumventions around stringlike singularities

  16. Bose-Einstein condensation in real space

    International Nuclear Information System (INIS)

    Valencia, J.J.; Llano, M. de; Solis, M.A.

    2004-01-01

    We show how Bose-Einstein condensation (BEC) occurs not only in momentum space but also in coordinate (or real) space. Analogies between the isotherms of a van der Waals classical gas of extended (or finite-diameter) identical atoms and the point (or zero-diameter) particles of an ideal BE gas allow concluding that, in contrast with the classical case, the volume per particle vanishes in the pure BE condensate phase precisely because the boson diameters are zero. Thus a BE condensate forms in real space without exhibiting a liquid branch as does the classical gas. (Author)

  17. Landau-Migdal parameters and pion condensation

    Energy Technology Data Exchange (ETDEWEB)

    Tatsumi, Toshitaka [Department of Physics, Kyoto Univ., Kyoto (Japan)

    1999-08-01

    The possibility of pion condensation, one of the long-standing issues in nuclear physics, is reexamined in the light of the recent experimental data on the giant Gamow-Teller resonance. The experimental result tells that the coupling of nucleon particle-hole states with {delta} isobar-hole states in the spin-isospin channel should be weaker than that previously believed. It, in turn, implies that nuclear matter has the making of pion condensation at low densities. The possibility and implications of pion condensation in the heavy-ion collisions and neutron stars should be seriously reconsidered. (author)

  18. Vortices in a rotating dark matter condensate

    International Nuclear Information System (INIS)

    Yu, Rotha P; Morgan, Michael J

    2002-01-01

    We examine vortices in a self-gravitating dark matter Bose-Einstein condensate (BEC), consisting of ultra-low mass scalar bosons that arise during a late-time cosmological phase transition. Rotation of the dark matter BEC imprints a background phase gradient on the condensate, which establishes a harmonic trap potential for vortices. A numerical simulation of vortex dynamics shows that the vortex number density, n v ∝ r -1 , resulting in a flat velocity profile for the dark matter condensate. (letter to the editor)

  19. Quark virtuality and QCD vacuum condensates

    International Nuclear Information System (INIS)

    Zhou Lijuan; Ma Weixing

    2004-01-01

    Based on the Dyson-Schwinger equations (DSEs) in the 'rainbow' approximation, the authors investigate the quark virtuality in the vacuum state and quantum-chromodynamics (QCD) vacuum condensates. In particular, authors calculate the local quark vacuum condensate and quark-gluon mixed condensates, and then the virtuality of quark. The calculated quark virtualities are λ u,d 2 =0.7 GeV 2 for u, d quarks, and λ s 2 =1.6 GeV 2 for s quark. The theoretical predictions are consistent with empirical values used in QCD sum rules, and also fit to lattice QCD predictions

  20. Capillary condensation between disks in two dimensions

    DEFF Research Database (Denmark)

    Gil, Tamir; Ipsen, John Hjorth

    1997-01-01

    Capillary condensation between two two-dimensional wetted circular substrates (disks) is studied by an effective free energy description of the wetting interface. The interfacial free-energy potential is developed on the basis of the theory for the wetting of a single disk, where interfacial...... capillary fluctuations play a dominant role. A simple approximative analytical expression of the interfacial free energy is developed and is validated numerically. The capillary condensation is characterized by the analysis of the coverage of the condensed phase, its stability, and asymptotic behaviors...

  1. Capillary condensation of adsorbates in porous materials.

    Science.gov (United States)

    Horikawa, Toshihide; Do, D D; Nicholson, D

    2011-11-14

    Hysteresis in capillary condensation is important for the fundamental study and application of porous materials, and yet experiments on porous materials are sometimes difficult to interpret because of the many interactions and complex solid structures involved in the condensation and evaporation processes. Here we make an overview of the significant progress in understanding capillary condensation and hysteresis phenomena in mesopores that have followed from experiment and simulation applied to highly ordered mesoporous materials such as MCM-41 and SBA-15 over the last few decades. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. Dynamics of capillary condensation in aerogels.

    Science.gov (United States)

    Nomura, R; Miyashita, W; Yoneyama, K; Okuda, Y

    2006-03-01

    Dynamics of capillary condensation of liquid 4He in various density silica aerogels was investigated systematically. Interfaces were clearly visible when bulk liquid was rapidly sucked into the aerogel. Time evolution of the interface positions was consistent with the Washburn model and their effective pore radii were obtained. Condensation was a single step in a dense aerogel and two steps in a low density aerogel. Crossover between the two types of condensation was observed in an intermediate density aerogel. Variety of the dynamics may be the manifestation of the fractal nature of aerogels which had a wide range of distribution of pore radii.

  3. QCD condensates in ADS/QCD

    DEFF Research Database (Denmark)

    Bechi, Jacopo

    2009-01-01

    This paper focuses on some issues about condensates and renormalization in AdS/QCD models. In particular we consider the consistency of the AdS/QCD approach for scale dependent quantities as the chiral condensate questioned in some recent papers and the 4D meaning of the 5D cosmological constant...... in a model in which the QCD is dual to a 5D gravity theory. We will be able to give some arguments that the cosmological constant is related to the QCD gluon condensate....

  4. Efficient, Long-Life Biocidal Condenser, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Environmental control systems for manned lunar and planetary bases will require condensing heat exchangers to control humidity. Condensing surfaces must be...

  5. Condensed Matter Theories: Volume 25

    Science.gov (United States)

    Ludeña, Eduardo V.; Bishop, Raymond F.; Iza, Peter

    2011-03-01

    dynamics and density functional theory. Exchange-correlation functionals from the identical-particle Ornstein-Zernike equation: Basic formulation and numerical algorithms / R. Cuevas-Saavedra and P. W. Ayers. Features and catalytic properties of RhCu: A review / S. Gonzalez, C. Sousa and F. Illas. Kinetic energy functionals: Exact ones from analytic model wave functions and approximate ones in orbital-free molecular dynamics / V. V. Karasiev ... [et al.]. Numerical analysis of hydrogen storage in carbon nanopores / C. Wexler ... [et al.] -- pt. F. Superconductivity. Generalized Bose-Einstein condensation in superconductivity / M. de Llano. Kohn anomaly energy in conventional superconductors equals twice the energy of the superconducting gap: How and why? / R. Chaudhury and M. P. Das. Collective excitations in superconductors and semiconductors in the presence of a condensed phase / Z. Koinov. Thermal expansion of ferromagnetic superconductors: Possible application to UGe[symbol] / N. Hatayama and R. Konno. Generalized superconducting gap in a Boson-Fermion model / T. A. Mamedov and M. de Llano. Influence of domain walls in the superconductor/ferromagnet proximity effect / E. J. Patino. Spin singlet and triplet superconductivity induced by correlated hopping interactions / L. A. Perez, J. S. Millan and C. Wang -- pt. G. Statistical mechanics, relativistic quantum mechanics. Boltzmann's ergodic hypothesis: A meeting place for two cultures / M. H. Lee. Electron-electron interaction in the non-relativistic limit / F. B. Malik.

  6. Holography, Gravity and Condensed Matter

    Energy Technology Data Exchange (ETDEWEB)

    Hartnoll, Sean [Stanford Univ., CA (United States). Dept. of Physics

    2017-12-20

    Over the five years of funding from this grant, I produced 26 publications. These include a book-long monograph on "Holographic Quantum Matter" that is currently in press with MIT press. The remainder were mostly published in Physical Review Letters, the Journal of High Energy Physics, Nature Physics, Classical and Quantum Gravity and Physical Review B. Over this period, the field of holography applied to condensed matter physics developed from a promising theoretical approach to a mature conceptual and practical edifice, whose ideas were realized in experiments. My own work played a central role in this development. In particular, in the final year of this grant, I co-authored two experimental papers in which ideas that I had developed in earlier years were shown to usefully describe transport in strongly correlated materials — these papers were published in Science and in the Proceedings of the National Academy of Sciences (obviously my contribution to these papers was theoretical). My theoretical work in this period developed several new directions of research that have proven to be influential. These include (i) The construction of highly inhomogeneous black hole event horizons, realizing disordered fixed points and describing new regimes of classical gravity, (ii) The conjecture of a bound on diffusivities that could underpin transport in strongly interacting media — an idea which may be proven in the near future and has turned out to be intimately connected to studies of quantum chaos in black holes and strongly correlated media, (iii) The characterization of new forms of hydrodynamic transport, e.g. with phase-disordered order parameters. These studies pertain to key open questions in our understanding of how non-quasiparticle, intrinsically strongly interacting systems can behave. In addition to the interface between holography and strongly interacting condensed matter systems, I made several advances on understanding the role of entanglement in quantum

  7. Fundamentals of evaporation and condensation phenomena

    International Nuclear Information System (INIS)

    Munir, Z.A.

    1979-01-01

    Fundamental relationships governing evaporation and condensation processes are reviewed. The terrace-ledge-kink (TLK) model is discussed in terms of atomic steps comprising growth and evaporation of crystals. Recent results in the field are described

  8. Vortex sorter for Bose-Einstein condensates

    International Nuclear Information System (INIS)

    Whyte, Graeme; Veitch, John; Courtial, Johannes; Oehberg, Patrik

    2004-01-01

    We have designed interferometers that sort Bose-Einstein condensates into their vortex components. The Bose-Einstein condensates in the two arms of the interferometer are rotated with respect to each other through fixed angles; different vortex components then exit the interferometer in different directions. The method we use to rotate the Bose-Einstein condensates involves asymmetric phase imprinting and is itself new. We have modeled rotation through fixed angles and sorting into vortex components with even and odd values of the topological charge of two-dimensional Bose-Einstein condensates in a number of states (pure or superposition vortex states for different values of the scattering length). Our scheme may have applications for quantum information processing

  9. Bose-Einstein condensation and crystallization

    International Nuclear Information System (INIS)

    Suetoe, A.

    2008-01-01

    The paper describes history and state of art theory of Bose-Einstein condensation and crystallization as cases of breaking continuous symmetries. Emphasizes that these problems have not been solved exactly. (TRA)

  10. The condensation of water on adsorbed viruses.

    Science.gov (United States)

    Alonso, José María; Tatti, Francesco; Chuvilin, Andrey; Mam, Keriya; Ondarçuhu, Thierry; Bittner, Alexander M

    2013-11-26

    The wetting and dewetting behavior of biological nanostructures and to a greater degree single molecules is not well-known even though their contact with water is the basis for all biology. Here, we show that environmental electron microscopy (EM) can be applied as a means of imaging the condensation of water onto viruses. We captured the formation of submicrometer water droplets and filaments on single viral particles by environmental EM and by environmental transmission EM. The condensate structures are compatible with capillary condensation between adsorbed virus particles and with known droplet shapes on patterned surfaces. Our results confirm that such droplets exist down to condensation/evaporation cycle as expected from their stability in air and water. Moreover we developed procedures that overcome problems of beam damage and of resolving structures with a low atomic number.

  11. Condenser design for AMTEC power conversion

    Science.gov (United States)

    Crowley, Christopher J.

    1991-01-01

    The condenser and the electrodes are the two elements of an alkali metal thermal-to-electric conversion (AMTEC) cell which most greatly affect the energy conversion performance. A condenser is described which accomplishes two critical functions in an AMTEC cell: management of the fluid under microgravity conditions and optimization of conversion efficiency. The first function is achieved via the use of a controlled surface shape, along with drainage grooves and arteries to collect the fluid. Capillary forces manage the fluid in microgravity and dominate hydrostatic effects on the ground so the device is ground-testable. The second function is achieved via a smooth film of highly reflective liquid sodium on the condensing surface, resulting in minimization of parasitic heat losses due to radiation heat transfer. Power conversion efficiencies of 25 percent to 30 percent are estimated with this condenser using present technology for the electrodes.

  12. Droplet condensation in rapidly decaying pressure fields

    International Nuclear Information System (INIS)

    Peterson, P.F.; Bai, R.Y.; Schrock, V.E.; Hijikata, K.

    1992-01-01

    Certain promising schemes for cooling inertial confinement fusion reactors call for highly transient condensation in a rapidly decaying pressure field. After an initial period of condensation on a subcooled droplet, undesirable evaporation begins to occur. Recirculation within the droplet strongly impacts the character of this condensation-evaporation cycle, particularly when the recirculation time constant is of the order of the pressure decay time constant. Recirculation can augment the heat transfer, delay the onset of evaporation, and increase the maximum superheat inside the drop by as much as an order of magnitude. This numerical investigation identifies the most important parameters and physics characterizing transient, high heat flux droplet condensation. The results can be applied to conceptual designs of inertial confinement fusion reactors, where initial temperature differences on the order of 1,500 K decay to zero over time spans the order of tens of milliseconds

  13. Accretion of Ghost Condensate by Black Holes

    Energy Technology Data Exchange (ETDEWEB)

    Frolov, A

    2004-06-02

    The intent of this letter is to point out that the accretion of a ghost condensate by black holes could be extremely efficient. We analyze steady-state spherically symmetric flows of the ghost fluid in the gravitational field of a Schwarzschild black hole and calculate the accretion rate. Unlike minimally coupled scalar field or quintessence, the accretion rate is set not by the cosmological energy density of the field, but by the energy scale of the ghost condensate theory. If hydrodynamical flow is established, it could be as high as tenth of a solar mass per second for 10MeV-scale ghost condensate accreting onto a stellar-sized black hole, which puts serious constraints on the parameters of the ghost condensate model.

  14. Recent developments in Bose-Einstein condensation

    International Nuclear Information System (INIS)

    Kalman, G.

    1997-01-01

    This paper contains viewgraphs on developments on Bose-Einstein condensation. Some topics covered are: strongly coupled coulomb systems; standard response functions of the first and second kind; dynamical mean field theory; quasi localized charge approximation; and the main equations

  15. Recent developments in Bose-Einstein condensation

    Energy Technology Data Exchange (ETDEWEB)

    Kalman, G.

    1997-09-22

    This paper contains viewgraphs on developments on Bose-Einstein condensation. Some topics covered are: strongly coupled coulomb systems; standard response functions of the first and second kind; dynamical mean field theory; quasi localized charge approximation; and the main equations.

  16. Avaliação do monômero residual de resinas acrílicas utilizadas para prótese ocular, polimerizadas convencionalmente e por energia de microondas = Evaluation of residual monomer between conventional and microwave heat-cured acrylic resins used for ocular prostheses

    Directory of Open Access Journals (Sweden)

    Moroni, Pedro Alexandre

    2005-01-01

    Full Text Available Este trabalho objetivou comparar a quantidade de monômero residual das resinas acrílicas utilizadas para confecção de prótese ocular, termopolimerizável incolor (grupo controle e Onda-Cryll incolor após a polimerização convencional (MC e com energia de microondas (MW respectivamente. Para o experimento foram confeccionados três corpos-de-prova para cada tipo de resina e período de investigação, num total de 30 corpos-de-prova, os quais foram submetidos a ensaios titulométricos nos períodos de 5, 30 60, 120 e 1. 440 minutos (24 horas após a demuflagem. A resina acrílica termopolimerizável incolor apresentou índice inferiores de concentração de monômero residual em relação à resina acrílica Onda-Cryll incolor. A resina acrílica polimerizada por microondas apresentou baixos indíces de concentração de monômero residual, porém um pouco superiores (até 120 minutos em relação à resina termopolimerizável incolor. Ambos os materiais apresentaram valores numéricos estatisticamente semelhantes de concentração de monômero residual no período de 1440 minutos (24horas. Uma técnica de confecção de prótese ocular através de forno de microondas é exeqüível, pois os acrílicos apresentam concentrações normais de monômero residual após 120 minutos da sua polimerização, em relação ao grupo controle

  17. Conditions for maximum isolation of stable condensate during separation in gas-condensate systems

    Energy Technology Data Exchange (ETDEWEB)

    Trivus, N.A.; Belkina, N.A.

    1969-02-01

    A thermodynamic analysis is made of the gas-liquid separation process in order to determine the relationship between conditions of maximum stable condensate separation and physico-chemical nature and composition of condensate. The analysis was made by considering the multicomponent gas-condensate fluid produced from Zyrya field as a ternary system, composed of methane, an intermediate component (propane and butane) and a heavy residue, C/sub 6+/. Composition of 5 ternary systems was calculated for a wide variation in separator conditions. At each separator pressure there is maximum condensate production at a certain temperature. This occurs because solubility of condensate components changes with temperature. Results of all calculations are shown graphically. The graphs show conditions of maximum stable condensate separation.

  18. Condensing and water supplying systems in an atomic power plant

    International Nuclear Information System (INIS)

    Shinmura, Akira.

    1975-01-01

    Object: To reduce heat loss and eliminate accumulation of drain in water supplying and heating units in an atomic power plant by providing a direct contact type drain cooler between a gland-exhauster vapor condenser and a condensing and de-salting means, the drain from each water supplying and heating unit being collected in said cooler for heating the condensed water. Structure: Condensed water from a condenser is fed by a low pressure condensing pump through an air ejector and gland-exhauster vapor condenser to the direct-contact type drain cooler and is condensed in each water supply heater. Next, it is heated by drain fed through a drain level adjuster valve and an orifice and then forced by a medium pressure condenser pump into the condensing and de-salting means. It is then supplied by a high pressure condensing pump into the successive water supply heater. (Kamimura, M.)

  19. Fermion condensation and gapped domain walls in topological orders

    Energy Technology Data Exchange (ETDEWEB)

    Wan, Yidun [Department of Physics and Center for Field Theory and Particle Physics, Fudan University,Shanghai 200433 (China); Collaborative Innovation Center of Advanced Microstructures, Nanjing University,Nanjing 210093 (China); Perimeter Institute for Theoretical Physics,Waterloo N2L 2Y5, Ontario (Canada); Wang, Chenjie [Perimeter Institute for Theoretical Physics,Waterloo N2L 2Y5, Ontario (Canada)

    2017-03-31

    We study fermion condensation in bosonic topological orders in two spatial dimensions. Fermion condensation may be realized as gapped domain walls between bosonic and fermionic topological orders, which may be thought of as real-space phase transitions from bosonic to fermionic topological orders. This picture generalizes the previous idea of understanding boson condensation as gapped domain walls between bosonic topological orders. While simple-current fermion condensation was considered before, we systematically study general fermion condensation and show that it obeys a Hierarchy Principle: a general fermion condensation can always be decomposed into a boson condensation followed by a minimal fermion condensation. The latter involves only a single self-fermion that is its own anti-particle and that has unit quantum dimension. We develop the rules of minimal fermion condensation, which together with the known rules of boson condensation, provides a full set of rules for general fermion condensation.

  20. Biofouling and its prevention in condenser tubes

    Energy Technology Data Exchange (ETDEWEB)

    Mimura, K; Minamoto, K; Kyohara, S [Kobe Steel Ltd. (Japan). Central Research and Development Lab.

    1979-04-01

    In this paper, biofouling in condenser tubes and methods of prevention are described. Biofouling has a tendency to occur in tubes under lower velocity of sea water, and fouling organisms, if allowed to build up, cannot be removed by ordinary nylon brush cleaning. As the results of our investigation, it was concluded that sponge ball cleaning should be employed when the condenser is operated under lower velocity of sea water in the bacteria breeding season.

  1. Chiral Lagrangians and quark condensate in nuclei

    International Nuclear Information System (INIS)

    Delorme, J.; Chanfray, G.; Ericson, M.

    1996-03-01

    The evolution of density of quark condensate in nuclear medium with interacting nucleons, including the short range correlations is examined. Two chiral models are used, the linear sigma model and the non-linear one. It is shown that the quark condensate, as other observables, is independent on the variant selected. The application to physical pions excludes the linear sigma model as a credible one. The non-linear models restricted to pure s-wave pion-nucleon scattering are examined. (author)

  2. Capillary condensation between disks in two dimensions

    OpenAIRE

    Gil, Tamir; Ipsen, John Hjorth

    1997-01-01

    Capillary condensation between two two-dimensional wetted circular substrates (disks) is studied by an effective free energy description of the wetting interface. The interfacial free-energy potential is developed on the basis of the theory for the wetting of a single disk, where interfacial capillary fluctuations play a dominant role. A simple approximative analytical expression of the interfacial free energy is developed and is validated numerically. The capillary condensation is characteri...

  3. Pion condensation in symmetric nuclear matter

    International Nuclear Information System (INIS)

    Kabir, K.; Saha, S.; Nath, L.M.

    1987-09-01

    Using a model which is based essentially on the chiral SU(2)xSU(2) symmetry of the pion-nucleon interaction, we examine the possibility of pion condensation in symmetric nucleon matter. We find that the pion condensation is not likely to occur in symmetric nuclear matter for any finite value of the nuclear density. Consequently, no critical opalescence phenomenon is expected to be seen in the pion-nucleus interaction. (author). 20 refs

  4. Pion condensation in symmetric nuclear matter

    Science.gov (United States)

    Kabir, K.; Saha, S.; Nath, L. M.

    1988-01-01

    Using a model which is based essentially on the chiral SU(2)×SU(2) symmetry of the pion-nucleon interaction, we examine the possibility of pion condensation in symmetric nucleon matter. We find that the pion condensation is not likely to occur in symmetric nuclear matter for any finite value of the nuclear density. Consequently, no critical opalescence phenomenom is expected to be seen in the pion-nucleus interaction.

  5. Vector condensate model of electroweak interactions

    International Nuclear Information System (INIS)

    Cynolter, G.; Pocsik, G.

    1997-01-01

    Motivated by the fact that the Higgs is not seen, a new version of the standard model is proposed where the scalar doublet is replaced by a vector doublet and its neutral member forms a nonvanishing condensate. Gauge fields are coupled to the new vector fields B in a gauge invariant way leading to mass terms for the gauge fields by condensation. The model is presented and some implications are discussed. (K.A.)

  6. The Effect of Capillary Number on a Condensate Blockage in Gas Condensate Reservoirs

    OpenAIRE

    Saifon DAUNGKAEW; Alain C GRINGARTEN

    2004-01-01

    In the petroleum industry, gas condensate reservoirs are becoming more common as exploration targets. However, there is a lack of knowledge of the reservoir behaviour mainly due to its complexity in the near wellbore region, where two phases, i.e. reservoir gas and condensate coexist when the wellbore pressure drops below the dew point pressure. The condensation process causes a reduction of the gas productivity (1). It has been reported in the literature that there is an increasing gas mobil...

  7. Primes, Geometry and Condensed Matter

    Directory of Open Access Journals (Sweden)

    Al Rabeh R. H.

    2009-07-01

    Full Text Available Fascination with primes dates back to the Greeks and before. Primes are named by some "the elementary particles of arithmetic" as every nonprime integer is made of a unique set of primes. In this article we point to new connections between primes, geometry and physics which show that primes could be called "the elementary particles of physics" too. This study considers the problem of closely packing similar circles/spheres in 2D/3D space. This is in effect a discretization process of space and the allowable number in a pack is found to lead to some unexpected cases of prime configurations which is independent of the size of the constituents. We next suggest that a non-prime can be considered geometrically as a symmetric collection that is separable (factorable into similar parts- six is two threes or three twos for example. A collection that has no such symmetry is a prime. As a result, a physical prime aggregate is more difficult to split symmetrically resulting in an inherent stability. This "number/physical" stability idea applies to bigger collections made from smaller (prime units leading to larger stable prime structures in a limitless scaling up process. The distribution of primes among numbers can be understood better using the packing ideas described here and we further suggest that differing numbers (and values of distinct prime factors making a nonprime collection is an important factor in determining the probability and method of possible and subsequent disintegration. Disintegration is bound by energy conservation and is closely related to symmetry by Noether theorems. Thinking of condensed matter as the packing of identical elements, we examine plots of the masses of chemical elements of the periodic table, and also those of the elementary particles of physics, and show that prime packing rules seem to play a role in the make up of matter. The plots show convincingly that the growth of prime numbers and that of the masses of

  8. Primes, Geometry and Condensed Matter

    Directory of Open Access Journals (Sweden)

    Al Rabeh R. H.

    2009-07-01

    Full Text Available Fascination with primes dates back to the Greeks and before. Primes are named by some “the elementary particles of arithmetic” as every nonprime integer is made of a unique set of primes. In this article we point to new connections between primes, geometry and physics which show that primes could be called “the elementary particles of physics” too. This study considers the problem of closely packing similar circles / spheres in 2D / 3D space. This is in effect a discretization process of space and the allowable num- ber in a pack is found to lead to some unexpected cases of prime configurations which is independent of the size of the constituents. We next suggest that a non-prime can be considered geometrically as a symmetric collection that is separable (factorable into similar parts- six is two threes or three twos for example. A collection that has no such symmetry is a prime. As a result, a physical prime aggregate is more difficult to split symmetrically resulting in an inherent stability. This “number / physical” stability idea applies to bigger collections made from smaller (prime units leading to larger sta- ble prime structures in a limitless scaling up process. The distribution of primes among numbers can be understood better using the packing ideas described here and we further suggest that differing numbers (and values of distinct prime factors making a nonprime collection is an important factor in determining the probability and method of possible and subsequent disintegration. Disintegration is bound by energy conservation and is closely related to symmetry by Noether theorems. Thinking of condensed matter as the packing of identical elements, we examine plots of the masses of chemical elements of the periodic table, and also those of the elementary particles of physics, and show that prime packing rules seem to play a role in the make up of matter. The plots show con- vincingly that the growth of prime numbers and that

  9. Mitotic chromosome condensation in vertebrates

    International Nuclear Information System (INIS)

    Vagnarelli, Paola

    2012-01-01

    Work from several laboratories over the past 10–15 years has revealed that, within the interphase nucleus, chromosomes are organized into spatially distinct territories [T. Cremer, C. Cremer, Chromosome territories, nuclear architecture and gene regulation in mammalian cells, Nat. Rev. Genet. 2 (2001) 292–301 and T. Cremer, M. Cremer, S. Dietzel, S. Muller, I. Solovei, S. Fakan, Chromosome territories—a functional nuclear landscape, Curr. Opin. Cell Biol. 18 (2006) 307–316]. The overall compaction level and intranuclear location varies as a function of gene density for both entire chromosomes [J.A. Croft, J.M. Bridger, S. Boyle, P. Perry, P. Teague,W.A. Bickmore, Differences in the localization and morphology of chromosomes in the human nucleus, J. Cell Biol. 145 (1999) 1119–1131] and specific chromosomal regions [N.L. Mahy, P.E. Perry, S. Gilchrist, R.A. Baldock, W.A. Bickmore, Spatial organization of active and inactive genes and noncoding DNA within chromosome territories, J. Cell Biol. 157 (2002) 579–589] (Fig. 1A, A'). In prophase, when cyclin B activity reaches a high threshold, chromosome condensation occurs followed by Nuclear Envelope Breakdown (NEB) [1]. At this point vertebrate chromosomes appear as compact structures harboring an attachment point for the spindle microtubules physically recognizable as a primary constriction where the two sister chromatids are held together. The transition from an unshaped interphase chromosome to the highly structured mitotic chromosome (compare Figs. 1A and B) has fascinated researchers for several decades now; however a definite picture of how this process is achieved and regulated is not yet in our hands and it will require more investigation to comprehend the complete process. From a biochemical point of view a vertebrate mitotic chromosomes is composed of DNA, histone proteins (60%) and non-histone proteins (40%) [6]. I will discuss below what is known to date on the contribution of these two different

  10. Improved Cloud Condensation Nucleus Spectrometer

    Science.gov (United States)

    Leu, Ming-Taun

    2010-01-01

    An improved thermal-gradient cloud condensation nucleus spectrometer (CCNS) has been designed to provide several enhancements over prior thermal- gradient counters, including fast response and high-sensitivity detection covering a wide range of supersaturations. CCNSs are used in laboratory research on the relationships among aerosols, supersaturation of air, and the formation of clouds. The operational characteristics of prior counters are such that it takes long times to determine aerosol critical supersaturations. Hence, there is a need for a CCNS capable of rapid scanning through a wide range of supersaturations. The present improved CCNS satisfies this need. The improved thermal-gradient CCNS (see Figure 1) incorporates the following notable features: a) The main chamber is bounded on the top and bottom by parallel thick copper plates, which are joined by a thermally conductive vertical wall on one side and a thermally nonconductive wall on the opposite side. b) To establish a temperature gradient needed to establish a supersaturation gradient, water at two different regulated temperatures is pumped through tubes along the edges of the copper plates at the thermally-nonconductive-wall side. Figure 2 presents an example of temperature and supersaturation gradients for one combination of regulated temperatures at the thermally-nonconductive-wall edges of the copper plates. c) To enable measurement of the temperature gradient, ten thermocouples are cemented to the external surfaces of the copper plates (five on the top plate and five on the bottom plate), spaced at equal intervals along the width axis of the main chamber near the outlet end. d) Pieces of filter paper or cotton felt are cemented onto the interior surfaces of the copper plates and, prior to each experimental run, are saturated with water to establish a supersaturation field inside the main chamber. e) A flow of monodisperse aerosol and a dilution flow of humid air are introduced into the main

  11. Mitotic chromosome condensation in vertebrates

    Energy Technology Data Exchange (ETDEWEB)

    Vagnarelli, Paola, E-mail: P.Vagnarelli@ed.ac.uk

    2012-07-15

    Work from several laboratories over the past 10-15 years has revealed that, within the interphase nucleus, chromosomes are organized into spatially distinct territories [T. Cremer, C. Cremer, Chromosome territories, nuclear architecture and gene regulation in mammalian cells, Nat. Rev. Genet. 2 (2001) 292-301 and T. Cremer, M. Cremer, S. Dietzel, S. Muller, I. Solovei, S. Fakan, Chromosome territories-a functional nuclear landscape, Curr. Opin. Cell Biol. 18 (2006) 307-316]. The overall compaction level and intranuclear location varies as a function of gene density for both entire chromosomes [J.A. Croft, J.M. Bridger, S. Boyle, P. Perry, P. Teague,W.A. Bickmore, Differences in the localization and morphology of chromosomes in the human nucleus, J. Cell Biol. 145 (1999) 1119-1131] and specific chromosomal regions [N.L. Mahy, P.E. Perry, S. Gilchrist, R.A. Baldock, W.A. Bickmore, Spatial organization of active and inactive genes and noncoding DNA within chromosome territories, J. Cell Biol. 157 (2002) 579-589] (Fig. 1A, A'). In prophase, when cyclin B activity reaches a high threshold, chromosome condensation occurs followed by Nuclear Envelope Breakdown (NEB) [1]. At this point vertebrate chromosomes appear as compact structures harboring an attachment point for the spindle microtubules physically recognizable as a primary constriction where the two sister chromatids are held together. The transition from an unshaped interphase chromosome to the highly structured mitotic chromosome (compare Figs. 1A and B) has fascinated researchers for several decades now; however a definite picture of how this process is achieved and regulated is not yet in our hands and it will require more investigation to comprehend the complete process. From a biochemical point of view a vertebrate mitotic chromosomes is composed of DNA, histone proteins (60%) and non-histone proteins (40%) [6]. I will discuss below what is known to date on the contribution of these two different classes

  12. Obtención de nano-estructuras bi-dimensionales de SnO2 utilizando el método pechini: estudio de la conformación de la resina

    Directory of Open Access Journals (Sweden)

    Rodriguez Paez, J. E.

    2008-10-01

    Full Text Available Pechini method has been widely used in the synthesis of oxides, but the physicochemical process that happens during this one have not been discussed in detail, for example the resin conformation that is obtained in one of the stages of the process. Knowing the resin evolution and since the most important parameter of this one are modified, it could determinate the most appropriate conditions to conform thin films though the Pechini method. In this work the resin evolution of the tin system considering parameters like pH, viscosity, time and temperature of heating were studied. Infrared spectroscopy (FTIR and viscosity measures in differents steps of the process were used. The IR spectroscopy results shows that as it advances the aging time of the resin, to a temperature between 80 and 100ºC and a pH of 6,5, Sn-O bonds are strengthen. Films were conformed with the resin obtained during the pechini process, it being defined a value of 110cP as the most appropriate to favor the homogeneity and adherence of this ones. The grain size film was of ∼110nm what indicates that the realized process allows to obtain bidimensional nano-structures.A pesar que el método de precursor polimérico, Pechini es ampliamente utilizado en la síntesis de óxidos, los procesos fisicoquímicos que ocurren durante el mismo no se han discutido en detalle; tal es el caso de la conformación de la resina que se obtiene en una de las etapas del proceso. Conociendo la evolución de esta resina, y como se modifican los parámetros más importantes de la misma, se podrían determinar las condiciones más adecuadas para conformar películas delgadas a través de este método. En este trabajo se estudio la evolución de la resina del sistema de estaño considerando parámetros como pH, viscosidad, tiempo y temperatura de calentamiento de la misma. Para este estudio se utilizó espectroscopía infrarroja (FTIR y medidas de viscosidad de la resina en diferentes instantes del

  13. Implementation of non-condensable gases condensation suppression model into the WCOBRA/TRAC-TF2 LOCA safety evaluation code

    Energy Technology Data Exchange (ETDEWEB)

    Liao, J.; Cao, L.; Ohkawa, K.; Frepoli, C. [LOCA Integrated Services I, Westinghouse Electric Company, 1000 Westinghouse Drive, Cranberry Township, PA 16066 (United States)

    2012-07-01

    The non-condensable gases condensation suppression model is important for a realistic LOCA safety analysis code. A condensation suppression model for direct contact condensation was previously developed by Westinghouse using first principles. The model is believed to be an accurate description of the direct contact condensation process in the presence of non-condensable gases. The Westinghouse condensation suppression model is further revised by applying a more physical model. The revised condensation suppression model is thus implemented into the WCOBRA/TRAC-TF2 LOCA safety evaluation code for both 3-D module (COBRA-TF) and 1-D module (TRAC-PF1). Parametric study using the revised Westinghouse condensation suppression model is conducted. Additionally, the performance of non-condensable gases condensation suppression model is examined in the ACHILLES (ISP-25) separate effects test and LOFT L2-5 (ISP-13) integral effects test. (authors)

  14. Resistência à tração entre amálgama e resina composta em diferentes condições de oxidação - estudo in vitro

    Directory of Open Access Journals (Sweden)

    YOUSSEF Michel Nicolau

    1999-01-01

    Full Text Available Este trabalho estuda in vitro a resistência à tração de corpos-de-prova de amálgama-resina composta unidos pelo adesivo dental Scotchbond Multi-Uso Plus. Os corpos-de-prova foram divididos em três grupos de dez, sendo que cada corpo era o resultado da união de dois discos, um de amálgama e outro de resina composta. Esses discos foram obtidos dentro de cilindros de baquelite e sofreram acabamento superficial com lixa de grana 600. Pretendeu-se simular a técnica do amalcomp e verificar a resistência à tração entre o amálgama e a resina composta em diferentes condições de oxidação do amálgama. Dos resultados obtidos e mediante análise de variância e teste de Tukey a 5%, pôde-se concluir que: o Grupo 3, que ficou na saliva artificial por trinta dias e portanto sofreu maior oxidação, apresenta resistência à tração superior e estatisticamente significante em relação aos grupos 1 e 2; o Grupo 2, que ficou na saliva por sete dias e sofreu menor oxidação, não apresenta resistência à tração estatisticamente superior ao Grupo 1 de amálgama recém-condensado.

  15. PRODUÇÃO DE CHAPAS DE PARTÍCULAS ORIENTADAS “OSB” DE Eucalyptus grandis COM DIFERENTES TEORES DE RESINA, PARAFINA E COMPOSIÇÃO EM CAMADAS

    Directory of Open Access Journals (Sweden)

    Setsuo Iwakiri

    2002-10-01

    Full Text Available Este trabalho foi desenvolvido com o objetivo de avaliar a influência dos seguintes parâmetros de processo de produção sobre as propriedades das chapas “OSB”: composição das chapas em camadas cruzadas com proporções face-miolo-face de 30-40-30 e 20-60-20 em relação à composição homogênea; e, quantidades de 3, 4,5 e 6,0% de resina fenol-formaldeído, com incorporação de 0,5 e 1,0% de emulsão de parafina. Os resultados demonstraram que a composição das chapas, com a relação 20-60-20, apresentou melhor balanço das propriedades de flexão estática entre os sentidos de ensaios paralelo e perpendicular ao plano da chapa. A quantidade de 6,0% de resina foi a que resultou em melhores propriedades físico-mecânicas das chapas “OSB”. A produção de chapas “OSB” de Eucalyptus grandis, com 4,5 e 6,0% de resina fenol-formaldeído, superou as exigências mínimas de propriedades mecânicas das chapas “OSB” referendadas pela norma canadense CSA 0437-0 (1993.

  16. Cold Vacuum Drying facility condensate collection system design description

    International Nuclear Information System (INIS)

    PITKOFF, C.C.

    1999-01-01

    This document describes the Cold Vacuum Drying Facility (CVDF) condensate collection system (CCS). The function of the CCS is to collect cooling coil condensate from air-handling units in the CVDF and to isolate the condensate in collection tanks until the condensate is determined to be acceptable to drain to the effluent drain collection basin

  17. 46 CFR 56.50-35 - Condensate pumps.

    Science.gov (United States)

    2010-10-01

    ... APPURTENANCES Design Requirements Pertaining to Specific Systems § 56.50-35 Condensate pumps. Two means shall be provided for discharging the condensate from the main condenser, one of which shall be mechanically... suction from the condenser and a discharge to the feed tank, it may be accepted as an independent...

  18. Estabilidade dimensional de uma resina acrílica para coroas provisórias em função de diferentes técnicas de processamento ao longo do tempo

    Directory of Open Access Journals (Sweden)

    David Alejandro García-López

    Full Text Available INTRODUÇÃO: A estabilidade dimensional das resinas acrílicas influencia na adaptação das coroas provisórias e, consequentemente, no resultado do tratamento reabilitador. OBJETIVO: Avaliar a estabilidade dimensional, ao longo do tempo, de uma resina acrílica processada de diferentes maneiras. MATERIAL E MÉTODO: Cinco técnicas de polimerização da resina acrílica foram testadas: I - polimerização térmica utilizando líquido de polimerização rápida em mufla; II - autopolimerização sob pressão; III - autopolimerização utilizando pincel; IV - autopolimerização após mistura (pó + líquido em pote Dappen e inserção em matriz de aço na fase arenosa; V - autopolimerização após mistura em pote Dappen com inserção na matriz metálica na fase plástica. Foram confeccionados dez corpos de prova para cada tipo de processamento. Avaliou-se a estabilidade dimensional por meio de matriz de aço inox confeccionada segundo a especificação nº19 da ADA. Os corpos de prova foram armazenados em água destilada a 37ºC e examinados nos períodos de 1 hora, 1, 7, 15, 10, 90 e 180 dias após a polimerização, com o auxílio de um microscópio óptico com aumento de 20×. Os resultados foram submetidos à análise de dupla variância (Teste de Tukey para Tempo e Técnica de processamento em nível de 5% de significância. RESULTADO: Todos os grupos experimentais apresentaram alterações dimensionais entre o sétimo e o 15º dia; após esse período de tempo, houve alterações dimensionais estatisticamente significantes, para as diferentes técnicas estudadas. CONCLUSÃO: A estabilidade dimensional da resina acrílica não sofreu influência das diferentes técnicas de processamento avaliadas; entretanto, foi influenciada pelo tempo de armazenamento.

  19. Influência da ciclagem térmica na resistência à flexão de resinas laboratoriais = The effect of thermo-cycling on flexural strength of laboratorial resins

    Directory of Open Access Journals (Sweden)

    Oliveira, Karla Mychellyne Costa

    2007-01-01

    Full Text Available Introdução: Uma nova geração de resinas laboratoriais contendo micro-partículas cerâmicas em sua composição tem sido introduzida no mercado com a finalidade de melhorar suas propriedades mecânicas. Objetivo: O objetivo deste estudo foi avaliar o efeito da termociclagem na resistência à flexão de três resinas laboratoriais. Materiais e método: Foram confeccionadas 48 barras com medidas de 2 mm × 2 mm × 25 mm, utilizando as resinas laboratoriais: G1 - RESILAB MASTER (Wilcos, Brasil, G2 - VITA VM LC (Vita Zanhfabrik, Germany, G3 - VITA ZETA LC (Vita Zanhfabrik, Germany. A metade das barras de cada grupo foi submetida a 3000 ciclos térmicos (5ºC/55ºC ± 1, com banhos de 30 s. Os ensaios mecânicos foram efetuados em máquina de ensaio universal EMIC com capacidade de carga de 100 kg e velocidade de 0,5 mm/min. Resultados: Os dados obtidos foram analisados estatisticamente pelo teste de ANOVA (two-way e Tukey (p < 0,05. As médias (± DP observadas para os grupos sem ciclagem foram: G1(112,6 ± 25,39, G2(116,5 ± 18,51 e G3(136,1 ± 24,34; e para os grupos com ciclagem: G1(91,8 ± 18,86, G2(101,9 ± 20,61 e G3(89,9 ± 23,05. Conclusão: Concluiu-se que a diminuição da resistência à flexão em MPa está diretamente dependente da ciclagem térmica nos grupos testados, sendo que os maiores valores foram obtidos pela resina VITA VM LC. Entretanto, na condição sem ciclagem térmica a VITA ZETA apresentou os maiores valores

  20. Influência da contaminação pela manipulação durante o procedimento restaurador sobre as propriedades mecânicas de duas resinas compostas fotopolimerizáveis

    OpenAIRE

    Heck, Mary A. Pereira

    2006-01-01

    Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências da Saúde. Programa de Pós-Graduação em Odontologia Avaliou-se, in vitro, o efeito da contaminação pela manipulação digital sobre a microdureza e resistência flexural das resinas Tetric Ceram e Filtek Z250, e identificou-se os agentes contaminantes por meio da microanálise por energia dispersiva. Os resultados mostraram que a manipulação com luva contaminada e luva contaminada limpa com álcool diminuiu a microdure...

  1. Dureza knoop de resinas compostas em função do número relativo de radicais livres Relative number of free radicals and knoop hardness of composites

    Directory of Open Access Journals (Sweden)

    Marco Aurélio de MENEZES

    1998-07-01

    Full Text Available A pesquisa teve a finalidade de determinar o número relativo de radicais livres e a dureza Knoop de três resinas compostas (Z100, Silux Plus e Heliomolar RO. Para o ensaio dos radicais livres, as irradiações foram: 110, 180, 300, 580 mW/cm2, pelos tempos de 10, 20, 30, 40, 50, 60, 80 e 90 segundos. As durezas foram determinadas com as cores claras com irradiação de 110 e 300 mW/cm2, por 20, 40, 60 e 80 segundos, nas faces da frente e do fundo, nas idades de 5 minutos, 1 hora, 1 dia, 1 semana e 1 mês. As conclusões foram: a resina Z100 apresentou cerca de 3 vezes mais radicais livres do que as outras; o número relativo de radicais livres aumenta com a intensidade e tempo de exposição; maior intensidade de luz aumentou a dureza; maior tempo de exposição aumentou as durezas das resinas Silux Plus e Heliomolar, mas não da Z100; a dureza aumentou com a idade até 1 mês; o lado da irradiação apresentou maior dureza do que o do fundo; a resina Z100 foi bem mais dura e sofreu menos a influência da irradiação.The present study had the purpose of determining the relative number of free radicals of three composites with clear and dark colors. Intensities of irradiation were: 110, 180, 300, and 580 mW/cm2, for 10, 20, 30, 40, 50, 60, 80 and 90 seconds. Hardness was determined for the clear colors of the composites, using 110 and 300 mW/cm2 irradiation intensities, for 20, 40, 60, and 80 seconds, on front and deep surfaces, at the ages of 5 minutes, 1 hour, 1 day, 1 week, and 1 month. The conclusions were that: depending on the resin, clear colors present more free radicals; the number of free radicals increases with higher intensity and longer irradiation time; composite Z100 is much richer in free radicals than Silux Plus and Heliomolar RO; higher intensity of irradiation leads to increasing hardness; longer irradiation time increases hardness of Silux Plus and Heliomolar RO, but not that of Z100; hardness increases with age; in depth

  2. Infiltração marginal em restaurações de resina composta com diferentes materiais adesivos intermediários = Marginal leakage in resin composite restorations lined with different adhesive materials

    Directory of Open Access Journals (Sweden)

    Moraes, Rafael Stanziona de

    2007-01-01

    Full Text Available Este estudo avaliou a capacidade de selamento de restaurações de resina composta com diferentes materiais adesivos intermediários. Cavidades Classe V padronizadas, com margens em esmalte e dentina/cemento, foram confeccionadas em incisivos bovinos. A resina de alto escoamento Fill Magic (Vigodent e o cimento ionomérico Vitremer (3M ESPE foram empregados como intermediários de restaurações com os compósitos Charisma e Solitaire (Heraeus Kulzer, formando 6 grupos (n = 14: [C1] – compósito microhíbrido Charisma; [C2] – Fill Magic + Charisma; [C3] – Vitremer + Charisma; [S1] – compósito condensável Solitaire; [S2] – Fill magic + Solitaire; [S3] – Vitremer + Solitaire. Após acabamento e polimento, as amostras foram armazenadas em solução fisiológica a 37ºC, por 30 dias, e então imersas em solução de fucsina básica a 0,5% por 24h. Os dentes foram longitudinalmente seccionados e a penetração do corante avaliada sob magnificância (40×, por dois examinadores, com escores padronizados. Os dados foram submetidos ao teste estatístico não-paramétrico de Kruskal-Wallis. Nas margens em esmalte, diferenças significativas foram verificadas apenas para a associação de intermediários à resina Solitaire, com os grupos S2 (p < 0,05 e S3 (p < 0,001 apresentando escores de infiltração significativamente maiores em relação aos demais. As margens em dentina/cemento apresentaram maior penetração em relação às margens em esmalte (p < 0,001. Apenas a associação do Vitremer às duas resinas melhorou o selamento deste substrato, com os grupos C3 (p < 0,001 e S3 (p < 0,05 apresentando os menores escores de infiltração

  3. Evaluation of the surface hardness of composite resins before and after polishing at different times Avaliação da dureza superficial de resinas compostas antes e após o polimento em diferentes tempos

    Directory of Open Access Journals (Sweden)

    Michelle Alexandra Chinelatti

    2006-06-01

    Full Text Available PURPOSE: The aim of this study was to evaluate the surface hardness of six composite resins: Revolution, Natural Flow, Fill Magic Flow, Flow-it! (flowables, Silux Plus (microfilled and Z100 (minifilled before and after polishing at different times. MATERIALS AND METHODS: For this purpose, 240 specimens (5mm diameter, 1.4mm high were prepared. Vickers hardness was determined before and after polishing at different times: immediately, 24h, 7 and 21 days after preparation of the samples. Statistical analysis was performed by ANOVA and Tukey test. RESULTS: There was no difference in the hardness of flowable resins, which had lower hardness than the minifilled resin. The minifilled resin showed the highest surface hardness as compared to the other materials (pPROPOSIÇÃO: O objetivo deste estudo foi avaliar a dureza superficial de seis resinas compostas - Revolution, Natural Flow, Fill Magic Flow, Flow-it! (flowables, Silux Plus (micropartículas e Z100 (híbrida - antes e após o polimento realizado em diferentes tempos. MATERIAL E MÉTODO: Foram confeccionados 240 corpos-de-prova circulares (5mm de diâmetro e 1,4mm de altura. A dureza Vickers foi obtida antes e após o polimento realizado em diferentes tempos: imediatamente, 24 horas, 7 dias e 21 dias após a confecção do corpo-de-prova. Os dados foram analisados estatisticamente por meio da ANOVA e do Teste de Tukey. RESULTADOS: Não houve diferença entre as resinas compostas flowable, as quais apresentaram os menores valores de dureza. A resina composta híbrida demonstrou os melhores resultados. Todos os materiais exibiram aumento de dureza após a realização do polimento, que foi mais evidente após 7 dias. CONCLUSÃO: Pôde-se concluir que, independente do tipo de resina composta, a dureza superficial foi consideravelmente maior quando o polimento foi realizado 1 semana após a confecção dos corpos-de-prova.

  4. Avaliação da transmissão de luz através de zircónia: translucidez e polimerização de um cimento de resina: um estudo piloto

    OpenAIRE

    Pomares, Vânia Alexandra Cândido

    2011-01-01

    Tese de mestrado, Medicina Dentária, Universidade de Lisboa, Faculdade de Medicina Dentária, 2011 O presente estudo laboratorial foi realizado com o objectivo de avaliar a influência da cerâmica de zircónia na polimerização de um cimento de resina fotopolimerizável, sendo igualmente avaliada a transmissão de luz através da mesma. Foram avaliadas três cerâmicas de zircónia: Lava (3M ESPE), Zirconia Traslucent (Zirkonzahn) e Zirconia Prettau (Zirkonzahn). De cada uma das cerâmicas mencionada...

  5. Vortices in trapped Bose-Einstein condensates

    International Nuclear Information System (INIS)

    Jackson, B.

    2000-09-01

    In this thesis we solve the Gross-Pitaevskii equation numerically in order to model the response of trapped Bose-Einstein condensed gases to perturbations by electromagnetic fields. First, we simulate output coupling of pulses from the condensate and compare our results to experiments. The excitation and separation of eigenmodes on flow through a constriction is also studied. We then move on to the main theme of this thesis: the important subject of quantised vortices in Bose condensates, and the relation between Bose-Einstein condensation and superfluidity. We propose methods of producing vortex pairs and rings by controlled motion of objects. Full three-dimensional simulations under realistic experimental conditions are performed in order to test the validity of these ideas. We link vortex formation to drag forces on the object, which in turn is connected with energy transfer to the condensate. We therefore argue that vortex formation by moving objects is intimately related to the onset of dissipation in superfluids. We discuss this idea in the context of a recent experiment, using simulations to provide evidence of vortex formation in the experimental scenario. Superfluidity is also manifest in the property of persistent currents, which is linked to vortex stability and dynamics. We simulate vortex line and ring motion, and find in both cases precessional motion and thermodynamic instability to dissipation. Strictly speaking, the Gross-Pitaevskii equation is valid only for temperatures far below the BEC transition. We end the thesis by describing a simple finite-temperature model to describe mean-field coupling between condensed and non-condensed components of the gas. We show that our hybrid Monte-Carlo/FFT technique can describe damping of the lowest energy excitations of the system. Extensions to this model and future research directions are discussed in the conclusion. (author)

  6. Deepak Condenser Model (DeCoM)

    Science.gov (United States)

    Patel, Deepak

    2013-01-01

    Development of the DeCoM comes from the requirement of analyzing the performance of a condenser. A component of a loop heat pipe (LHP), the condenser, is interfaced with the radiator in order to reject heat. DeCoM simulates the condenser, with certain input parameters. Systems Improved Numerical Differencing Analyzer (SINDA), a thermal analysis software, calculates the adjoining component temperatures, based on the DeCoM parameters and interface temperatures to the radiator. Application of DeCoM is (at the time of this reporting) restricted to small-scale analysis, without the need for in-depth LHP component integrations. To efficiently develop a model to simulate the LHP condenser, DeCoM was developed to meet this purpose with least complexity. DeCoM is a single-condenser, single-pass simulator for analyzing its behavior. The analysis is done based on the interactions between condenser fluid, the wall, and the interface between the wall and the radiator. DeCoM is based on conservation of energy, two-phase equations, and flow equations. For two-phase, the Lockhart- Martinelli correlation has been used in order to calculate the convection value between fluid and wall. Software such as SINDA (for thermal analysis analysis) and Thermal Desktop (for modeling) are required. DeCoM also includes the ability to implement a condenser into a thermal model with the capability of understanding the code process and being edited to user-specific needs. DeCoM requires no license, and is an open-source code. Advantages to DeCoM include time dependency, reliability, and the ability for the user to view the code process and edit to their needs.

  7. A study on passive containment cooling condensers in SBWR

    International Nuclear Information System (INIS)

    Kuran, S.; Soekmen; C. N.

    2001-01-01

    The passive containment cooling condensers (PCCC) are the crucial part of several new reactor designs, like European Simplified Boiling Water Reactor (ESBWR) and the SBWR. In a hypothetical accident, the pressurised steam non-condensable mixture from drywell is condensed in PCCCs, and condensate is returned to reactor vessel while non-condensable is vented through wet well. In this study, in order to examine the performance of PCCCs, condensation with presence of noncondensable is investigated. Condensation with different noncondensable types and conditions is studied on a PCCC model, which is developed by using RELAP5 Mod3.2 computer code

  8. Improved condenser design and condenser-fan operation for air-cooled chillers

    International Nuclear Information System (INIS)

    Yu, F.W.; Chan, K.T.

    2006-01-01

    Air-cooled chillers traditionally operate under head pressure control via staging constant-speed condenser fans. This causes a significant drop in their coefficient of performance (COP) at part load or low outdoor temperatures. This paper describes how the COP of these chillers can be improved by a new condenser design, using evaporative pre-coolers and variable-speed fans. A thermodynamic model for an air-cooled screw-chiller was developed, within which the condenser component considers empirical equations showing the effectiveness of an evaporative pre-cooler in lowering the outdoor temperature in the heat-rejection process. The condenser component also contains an algorithm to determine the number and speed of the condenser fans staged at any given set point of condensing temperature. It is found that the chiller's COP can be maximized by adjusting the set point based on any given chiller load and wet-bulb temperature of the outdoor air. A 5.6-113.4% increase in chiller COP can be achieved from the new condenser design and condenser fan operation. This provides important insights into how to develop more energy-efficient air-cooled chillers

  9. Condensate and feedwater systems, pumps, and water chemistry. Volume seven

    International Nuclear Information System (INIS)

    Anon.

    1986-01-01

    Subject matter includes condensate and feedwater systems (general features of condensate and feedwater systems, condenser hotwell level control, condensate flow, feedwater flow), pumps (principles of fluid flow, types of pumps, centrifugal pumps, positive displacement pumps, jet pumps, pump operating characteristics) and water chemistry (water chemistry fundamentals, corrosion, scaling, radiochemistry, water chemistry control processes, water pretreatment, PWR water chemistry, BWR water chemistry, condenser circulating water chemistry

  10. Energy condensed packaged systems. Composition, production, properties

    Directory of Open Access Journals (Sweden)

    Igor L. Kovalenko

    2015-03-01

    Full Text Available In this paper it is presented the substantiation of choice of fuel phase composition and optimal technology of emulsion production on the basis of binary solution of ammonium and calcium nitrates, which provide the obtaining of energy condensed packaged systems with specified properties. The thermal decomposition of energy condensed systems on the basis of ammonium nitrate is investigated. It is shown that the fuel phase of emulsion systems should be based on esters of polyunsaturated acids or on combinations thereof with petroleum products. And ceresin or petroleum wax can be used as the structuring additive. The influence of the technology of energy condensed systems production on the physicochemical and detonation parameters of emulsion explosives is considered. It is shown the possibility of obtaining of emulsion systems with dispersion of 1.3...1.8 microns and viscosity higher than 103 Pa∙s in the apparatus of original design. The sensitizing effect of chlorinated paraffin CP-470 on the thermolysis of energy condensed emulsion system is shown. The composition and production technology of energy condensed packaged emulsion systems of mark Ukrainit-P for underground mining in mines not dangerous on gas and dust are developed.

  11. Condensed images for evaluating gastric motility patterns

    Energy Technology Data Exchange (ETDEWEB)

    Tatsch, K.; Schroettle, W.; Kirsch, C.-M. (Munich Univ. (Germany, F.R.). Dept. of Radiology)

    1991-04-01

    A condensed imaging technique was applied to gastric emptying studies to investigate (a) whether different types of motility disorders may be distinguished by characteristic image patterns and (b) whether the findings obtained provide additional information compared to standard quantitative measurements. Condensed images and quantitative data of gastric emptying were evaluated in 75 consecutive patients with normal function and various disorders such as peptic ulcer, postvagotomy, pyloric obstruction, dumping syndrome, gastoparesis etc. Condensed images were generated from a gastric region of interest. They display the distribution and behaviour of a radioactive test meal in a space-time matrix, whose horizontal and vertical dimensions are temporal and spatial, respectively. As shown in a series of representative examples condensed images disclose a variety of well-defined image patterns reflecting different pathophysiological mechanisms. This qualitative characterization of gastric emptying patterns provided in 34 of the 75 patients (45%) important new information compared to quantitative data. The application of condensed imaging techniques to gastric emptying studies (complementary to quantitative measurements) may, therefore, enhance the diagnostic value of scintigraphic techniques. (author).

  12. Dropwise condensation on hydrophobic bumps and dimples

    Science.gov (United States)

    Yao, Yuehan; Aizenberg, Joanna; Park, Kyoo-Chul

    2018-04-01

    Surface topography plays an important role in promoting or suppressing localized condensation. In this work, we study the growth of water droplets on hydrophobic convex surface textures such as bumps and concave surface textures such as dimples with a millimeter scale radius of curvature. We analyze the spatio-temporal droplet size distribution under a supersaturation condition created by keeping the uniform surface temperature below the dew point and show its relationship with the sign and magnitude of the surface curvature. In particular, in contrast to the well-known capillary condensation effect, we report an unexpectedly less favorable condensation on smaller, millimeter-scale dimples where the capillary condensation effect is negligible. To explain these experimental results, we numerically calculated the diffusion flux of water vapor around the surface textures, showing that its magnitude is higher on bumps and lower on dimples compared to a flat surface. We envision that our understanding of millimetric surface topography can be applied to improve the energy efficiency of condensation in applications such as water harvesting, heating, ventilation, and air conditioning systems for buildings and transportation, heat exchangers, thermal desalination plants, and fuel processing systems.

  13. Increasing the efficiency of the condensing boiler

    Science.gov (United States)

    Zaytsev, ON; Lapina, EA

    2017-11-01

    Analysis of existing designs of boilers with low power consumption showed that the low efficiency of the latter is due to the fact that they work in most cases when the heating period in the power range is significantly less than the nominal power. At the same time, condensing boilers do not work in the most optimal mode (in condensing mode) in the central part of Russia, a significant part of their total operating time during the heating season. This is due to existing methods of equipment selection and joint operation with heating systems with quantitative control of the coolant. It was also revealed that for the efficient operation of the heating system, it is necessary to reduce the inertia of the heat generating equipment. Theoretical patterns of thermal processes in the furnace during combustion gas at different radiating surfaces location schemes considering the influence of the very furnace configuration, characterized in that to reduce the work condensing boiler in conventional gas boiler operation is necessary to maintain a higher temperature in the furnace (in the part where spiral heat exchangers are disposed), which is possible when redistributing heat flow - increase the proportion of radiant heat from the secondary burner emitter allow Perey For the operation of the condensing boiler in the design (condensation) mode practically the entire heating period.

  14. Condensation on a cooled plane upright wall

    International Nuclear Information System (INIS)

    Fortier, Andre.

    1975-01-01

    The vapor condensation along a cooled upright plane wall was studied. The theoretical and experimental results obtained in the simple case, give the essential characteristics of the phenomenon of condensation along a cold wall that keeps the vapor apart from the coolant inside a surface condenser. The phenomenon presents two different appearances according as the wall is wetted or not by the liquid. In the first case a continuous liquid film runs down the wall and a conventional Nusselt calculation gives the film thickness and the heat exchange coefficient between a pure saturated vapor and the cold wall. The calculation is developed in detail and the effect of a vapor flow along the film is discussed as well as that of the presence of a noncondensable gas inside the vapor. In the second case, separated liquid drops are formed on the wall, the phenomenon is called ''dropwise condensation'' and the heat exchange coefficients obtained are much higher than with film condensation. The theoretical aspects of the problem are discussed with some experimental results [fr

  15. Condensate cosmology: Dark energy from dark matter

    International Nuclear Information System (INIS)

    Bassett, Bruce A.; Parkinson, David; Kunz, Martin; Ungarelli, Carlo

    2003-01-01

    Imagine a scenario in which the dark energy forms via the condensation of dark matter at some low redshift. The Compton wavelength therefore changes from small to very large at the transition, unlike quintessence or metamorphosis. We study cosmic microwave background (CMB), large scale structure, supernova and radio galaxy constraints on condensation by performing a four parameter likelihood analysis over the Hubble constant and the three parameters associated with Q, the condensate field: Ω Q , w f and z t (energy density and equation of state today, and redshift of transition). Condensation roughly interpolates between ΛCDM (for large z t ) and SCDM (low z t ) and provides a slightly better fit to the data than ΛCDM. We confirm that there is no degeneracy in the CMB between H and z t and discuss the implications of late-time transitions for the Lyman-α forest. Finally we discuss the nonlinear phase of both condensation and metamorphosis, which is much more interesting than in standard quintessence models

  16. Steam condensation modelling in aerosol codes

    International Nuclear Information System (INIS)

    Dunbar, I.H.

    1986-01-01

    The principal subject of this study is the modelling of the condensation of steam into and evaporation of water from aerosol particles. These processes introduce a new type of term into the equation for the development of the aerosol particle size distribution. This new term faces the code developer with three major problems: the physical modelling of the condensation/evaporation process, the discretisation of the new term and the separate accounting for the masses of the water and of the other components. This study has considered four codes which model the condensation of steam into and its evaporation from aerosol particles: AEROSYM-M (UK), AEROSOLS/B1 (France), NAUA (Federal Republic of Germany) and CONTAIN (USA). The modelling in the codes has been addressed under three headings. These are the physical modelling of condensation, the mathematics of the discretisation of the equations, and the methods for modelling the separate behaviour of different chemical components of the aerosol. The codes are least advanced in area of solute effect modelling. At present only AEROSOLS/B1 includes the effect. The effect is greater for more concentrated solutions. Codes without the effect will be more in error (underestimating the total airborne mass) the less condensation they predict. Data are needed on the water vapour pressure above concentrated solutions of the substances of interest (especially CsOH and CsI) if the extent to which aerosols retain water under superheated conditions is to be modelled. 15 refs

  17. Bose condensates make quantum leaps and bounds

    International Nuclear Information System (INIS)

    Castin, Y.; Dum, R.; Sinatra, A.

    1999-01-01

    Since the first observation in 1995 of Bose-Einstein condensation in dilute atomic gases, atomic physicists have made extraordinary progress in understanding this unusual quantum state of matter. BOSE-EINSTEIN condensation is a macroscopic quantum phenomenon that was first predicted by Albert Einstein in the 1920s, at a time when quantum theory was still developing and was being applied to microscopic systems, such as individual particles and atoms. Einstein applied the new concept of Bose statistics to an ideal gas of identical atoms that were at thermal equilibrium and trapped in a box. He predicted that at sufficiently low temperatures the particles would accumulate in the lowest quantum state in the box, giving rise to a new state of matter with many unusual properties. The crucial point of Einstein's model is the absence of interactions between the particles in the box. However, this makes his prediction difficult to test in practice. In most real systems the complicating effect of particle interactions causes the gas to solidify well before the temperature for Bose-Einstein condensation is reached. But techniques developed in the past four years have allowed physicists to form Bose-Einstein condensates for a wide range of elements. In this article the authors describe the latest advances in Bose-Einstein condensation. (UK)

  18. Quantificação por NIR/MIR de resina poliuretânica em misturas binárias com nitrocelulose utilizadas em tintas

    Directory of Open Access Journals (Sweden)

    Viviane Cristine Rodrigues

    2014-06-01

    Full Text Available Foi elaborada uma nova metodologia nas regiões do infravermelho médio (MIR e do infravermelho próximo (NIR, usando-se técnicas de Reflexão e/ou Transmissão para a determinação do teor de resina poliuretânica (PU em misturas binárias com nitrocelulose (NC, utilizadas em formulações de tintas. A técnica de Reflexão Total Atenuada Universal (UATR se mostrou útil na região MIR, para tal fim. Após a avaliação de diferentes bandas analíticas, de referência e de linhas de base, a banda relativa (A1541/ A1645 foi escolhida para a elaboração da curva de calibração, com erro de metodologia de 1,42%. As técnicas de Transmissão e Reflexão (DRIFT foram utilizadas na região NIR (banda relativa A5902/ A5262 para validação, apresentando erros de metodologia de 1,42% e 1,60 %, respectivamente. Todos os erros relativos nas metodologias apresentaram-se dentro dos limites de precisão da análise quantitativa FT-IR, para as condições usadas (≤2%. A análise de amostras teste confirmou a precisão das metodologias desenvolvidas, que também apresentam praticidade, baixo custo e tempo reduzido de análise.

  19. Efeito do ascorbato de sódio na adesividade da resina composta em dentes clareados = Effect of sodium ascorbate on composite resin bond strength to bleached teeth

    Directory of Open Access Journals (Sweden)

    Xavier, Ana Claudia Carvalho

    2014-01-01

    Full Text Available Objetivo: Avaliar o efeito do ascorbato de sódio na adesão de resina composta em dentes submetidos a tratamento clareador. Métodos: Foram utilizados 40 pré-molares humanos, divididos em 4 grupos: C – (controle dentes não clareados; S – dentes clareados com peróxido de hidrogênio 35% e armazenados por 48 horas em saliva artificial; AS – dentes clareados com peróxido de hidrogênio 35% e irrigados com solução de ascorbato de sódio 10% por 10 minutos; AG – dentes submetidos a tratamento clareador com peróxido de hidrogênio 35% e imersos em gel de ascorbato de sódio 10% por 3 horas. Após a restauração, as amostras foram seccionadas e submetidas ao teste de microtração em máquina de ensaios universais (Emic sob velocidade de 1 mm/min. Os dados foram avaliados e submetidos aos testes estatísticos ANOVA e Tukey, com nível de significância 5%. Resultados: O grupo C apresentou o maior valor de adesividade, diferindo estatisticamente dos grupos S e AG. Conclusão: A manutenção dos dentes clareados em saliva por 48 horas não é suficiente para a recuperação da resistência adesiva. No entanto, a utilização da solução de ascorbato de sódio 10% por 10 minutos pode promover uma resistência adesiva adequada, permitindo a imediata restauração dos dentes

  20. Assessment of horizontal in-tube condensation models using MARS code. Part I: Stratified flow condensation

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Seong-Su [Department of Engineering Project, FNC Technology Co., Ltd., Bldg. 135-308, Seoul National University, Gwanak-gu, Seoul 151-744 (Korea, Republic of); Department of Nuclear Engineering, Seoul National University, Gwanak-gu, Seoul 151-744 (Korea, Republic of); Hong, Soon-Joon, E-mail: sjhong90@fnctech.com [Department of Engineering Project, FNC Technology Co., Ltd., Bldg. 135-308, Seoul National University, Gwanak-gu, Seoul 151-744 (Korea, Republic of); Park, Ju-Yeop; Seul, Kwang-Won [Korea Institute of Nuclear Safety, 19 Kuseong-dong, Yuseong-gu, Daejon (Korea, Republic of); Park, Goon-Cherl [Department of Nuclear Engineering, Seoul National University, Gwanak-gu, Seoul 151-744 (Korea, Republic of)

    2013-01-15

    Highlights: Black-Right-Pointing-Pointer This study collected 11 horizontal in-tube condensation models for stratified flow. Black-Right-Pointing-Pointer This study assessed the predictive capability of the models for steam condensation. Black-Right-Pointing-Pointer Purdue-PCCS experiments were simulated using MARS code incorporated with models. Black-Right-Pointing-Pointer Cavallini et al. (2006) model predicts well the data for stratified flow condition. Black-Right-Pointing-Pointer Results of this study can be used to improve condensation model in RELAP5 or MARS. - Abstract: The accurate prediction of the horizontal in-tube condensation heat transfer is a primary concern in the optimum design and safety analysis of horizontal heat exchangers of passive safety systems such as the passive containment cooling system (PCCS), the emergency condenser system (ECS) and the passive auxiliary feed-water system (PAFS). It is essential to analyze and assess the predictive capability of the previous horizontal in-tube condensation models for each flow regime using various experimental data. This study assessed totally 11 condensation models for the stratified flow, one of the main flow regime encountered in the horizontal condenser, with the heat transfer data from the Purdue-PCCS experiment using the multi-dimensional analysis of reactor safety (MARS) code. From the assessments, it was found that the models by Akers and Rosson, Chato, Tandon et al., Sweeney and Chato, and Cavallini et al. (2002) under-predicted the data in the main condensation heat transfer region, on the contrary to this, the models by Rosson and Meyers, Jaster and Kosky, Fujii, Dobson and Chato, and Thome et al. similarly- or over-predicted the data, and especially, Cavallini et al. (2006) model shows good predictive capability for all test conditions. The results of this study can be used importantly to improve the condensation models in thermal hydraulic code, such as RELAP5 or MARS code.

  1. Recuperación de oro desde un medio amoniaco-tiosulfato con resina de intercambio iónico Amberlite IRA-410

    Directory of Open Access Journals (Sweden)

    Navarro, P.

    2006-10-01

    Full Text Available The adsorption and elution of gold in thiosulfate-ammonia media were studied at laboratory level using the Amberlite IRA-410 ionic exchange resin. Tests were carried out in a stirred reactor, maintaining constant temperature (25 ºC, with a volume of solution/mass of resin ratio of 833,3 ml/g and during 3 h. The variables tested were the following: pH (9-11, thiosulfate concentration (0-0,5 M, ammonia concentration (0-0,5 M and selectivity in the presence of cupric ion. The obtained results indicate that gold adsorption was quick; the presence of thiosulfate decreased strongly the adsorption; and the presence of ammonia did not affect the adsorption mostly. The copper was in a certain measure a competitor of the gold, but its biggest negative effect was that acted as catalyst of the oxidizing reaction of thiosulfate (S2O3 2– to tetrathionate (S4O6 2– and trithionate (S3O6 2–, which can cause a partial elution of gold during the load stage. Also, the behavior of ClO– 4, SO3 2– and ClO– as eluents was studied in both gold and copper elution. These tests were also carried out in a stirred reactor, to constant temperature (25 ºC, with a volume of aqueous solution/mass of resin ratio of 200 ml/g and for 3 h. Results demonstrated that the copper was eluted more quickly that the gold in all the cases.

    Se estudió, a nivel de laboratorio, la adsorción y desorción de oro utilizando la resina de intercambio iónico Amberlite IRA-410 en medio tiosulfato-amoniaco. Los ensayos se realizaron en un reactor agitado, manteniendo constante la temperatura en 25 ºC y con una razón volumen de disolución/masa de resina de 833,3 ml/g durante 3 h. Las variables evaluadas fueron las siguientes: pH de 9 a 11, concentración de tiosulfato de 0 a 0,5 M, concentración de amoniaco de 0 a 0,5 M y selectividad frente al i

  2. Fermion masses through four-fermion condensates

    Energy Technology Data Exchange (ETDEWEB)

    Ayyar, Venkitesh [Department of Physics, Duke University,Science Drive, Durham, NC 27708 (United States); Chandrasekharan, Shailesh [Department of Physics, Duke University,Science Drive, Durham, NC 27708 (United States); Center for High Energy Physics, Indian Institute of Science,C.V. Raman Avenue, Bangalore, 560012 (India)

    2016-10-12

    Fermion masses can be generated through four-fermion condensates when symmetries prevent fermion bilinear condensates from forming. This less explored mechanism of fermion mass generation is responsible for making four reduced staggered lattice fermions massive at strong couplings in a lattice model with a local four-fermion coupling. The model has a massless fermion phase at weak couplings and a massive fermion phase at strong couplings. In particular there is no spontaneous symmetry breaking of any lattice symmetries in both these phases. Recently it was discovered that in three space-time dimensions there is a direct second order phase transition between the two phases. Here we study the same model in four space-time dimensions and find results consistent with the existence of a narrow intermediate phase with fermion bilinear condensates, that separates the two asymptotic phases by continuous phase transitions.

  3. Preoperational test report, recirculation condenser cooling systems

    International Nuclear Information System (INIS)

    Clifton, F.T.

    1997-01-01

    This represents a preoperational test report for Recirculation Condenser Systems, Project W-030. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The four system provide condenser cooling water for vapor space cooling of tanks AY1O1, AY102, AZ1O1, AZ102. Each system consists of a valved piping loop, a pair of redundant recirculation pumps, a closed-loop evaporative cooling tower, and supporting instrumentation; equipment is located outside the farm on concrete slabs. Piping is routed to the each ventilation condenser inside the farm via below-grade concrete trenches. The tests verify correct system operation and correct indications displayed by the central Monitor and Control System

  4. Bose-Einstein condensation of atomic gases

    International Nuclear Information System (INIS)

    Anglin, J. R.; Ketterle, W.

    2003-01-01

    The early experiments on Bose-Einstein condensation in dilute atomic gases accomplished three longstanding goals. First, cooling of neutral atoms into their motional state, thus subjecting them to ultimate control, limited only by Heisenberg uncertainty relation. Second, creation of a coherent sample of atoms, in which all occupy the same quantum states, and the realization of atom lasers - devices that output coherent matter waves. And third, creation of gaseous quantum fluid, with properties that are different from the quantum liquids helium-3 and helium-4. The field of Bose-Einstein condensation of atomic gases has continued to progress rapidly, driven by the combination of new experimental techniques and theoretical advances. The family of quantum degenerate gases has grown, and now includes metastable and fermionic atoms. condensates have become an ultralow-temperature laboratory for atom optics, collisional physics and many-body physics, encompassing phonons, superfluidity, quantized vortices, Josephson junctions and quantum phase transitions. (author)

  5. Preoperational test report, recirculation condenser cooling systems

    Energy Technology Data Exchange (ETDEWEB)

    Clifton, F.T.

    1997-11-04

    This represents a preoperational test report for Recirculation Condenser Systems, Project W-030. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The four system provide condenser cooling water for vapor space cooling of tanks AY1O1, AY102, AZ1O1, AZ102. Each system consists of a valved piping loop, a pair of redundant recirculation pumps, a closed-loop evaporative cooling tower, and supporting instrumentation; equipment is located outside the farm on concrete slabs. Piping is routed to the each ventilation condenser inside the farm via below-grade concrete trenches. The tests verify correct system operation and correct indications displayed by the central Monitor and Control System.

  6. Condensate recovery by cycling at declining pressures

    Energy Technology Data Exchange (ETDEWEB)

    Havlena, Z G; Griffith, J D; Pot, R; Kiel, O G

    1967-06-05

    Cycling condensate reservoirs under conditions of declining pressure, rather than constant pressure, is advantageous from both a recovery and an economic standpoint. Wet gas displaced from the swept areas is recovered concurrently with wet gas recovered by gas expansion from the unswept portions of the reservoir. Any liquid condensed in the swept areas is revaporized by dry injection gas and recovered as an enriched gas. By this mode of operation, high condensate recovery is obtained, gas sales may be possible at an earlier stage of depletion, more flexibility in field and plant operations is feasible and reduction of 15% in investment and operating costs is achieved. Injection gas requirements are reduced by 40%. The Windfall reservoir in Canada has been successfully produced in this manner, starting in 1962. It is a typical retrograde type reservoir which in 1965 represented 15% of reservoirs exploited in North America.

  7. Using helical compressors for coke gas condensation

    Energy Technology Data Exchange (ETDEWEB)

    Privalov, V E; Rezunenko, Yu I; Lelyanov, N V; Zarnitzkii, G Eh; Gordienko, A A; Derebenko, I F; Venzhega, A G; Leonov, N P; Gorokhov, N N

    1982-08-01

    Coke oven gas compression is discussed. Presently used multilevel piston compressors are criticized. The paper recommends using helical machines which combine advantages of using volume condensing compressors and compact high-efficiency centrifugal machines. Two kinds of helical compressors are evaluated: dry and oil-filled; their productivities and coke oven gas chemical composition are analyzed. Experiments using helical compressors were undertaken at the Yasinovskii plant. Flowsheet of the installation is shown. Performance results are given in a table. For all operating conditions content of insolubles in oil compounds is found to be lower than the acceptable value (0.08%). Compressor productivity measurements with variable manifold pressure are evaluated. Figures obtained show that efficient condensation of raw coke oven gas is possible. Increasing oil-filled compressor productivity is recommended by decreasing amount of oil injected and simultaneously increasing rotation speed. The dry helical compressor with water seal is found to be most promising for raw coke oven gas condensation. (10 refs.)

  8. Dropwise condensation on inclined textured surfaces

    CERN Document Server

    Khandekar, Sameer

    2014-01-01

    Dropwise Condensation on Textured Surfaces presents a holistic framework for understanding dropwise condensation through mathematical modeling and meaningful experiments. The book presents a review of the subject required to build up models as well as to design experiments. Emphasis is placed on the effect of physical and chemical texturing and their effect on the bulk transport phenomena. Application of the model to metal vapor condensation is of special interest. The unique behavior of liquid metals, with their low Prandtl number and high surface tension, is also discussed. The model predicts instantaneous drop size distribution for a given level of substrate subcooling and derives local as well as spatio-temporally averaged heat transfer rates and wall shear stress.

  9. Temporal dynamics of Bose-condensed gases

    Energy Technology Data Exchange (ETDEWEB)

    Trujillo Martinez, Mauricio

    2014-03-19

    We perform a detailed quantum dynamical study of non-equilibrium trapped, interacting Bose-condensed gases. We investigate Josephson oscillations between interacting Bose-Einstein condensates confined in a finite size double-well trap and the non-trivial time evolution of a coherent state placed at the center of a two dimensional optical lattice. For the Josephson oscillations three time scales appear. We find that Josephson junction can sustain multiple undamped oscillations up to a characteristic time scale τ{sub c} without exciting atoms out of the condensates. Beyond the characteristic time scale τ{sub c} the dynamics of the junction are governed by fast, non-condensed particles assisted Josephson tunnelling as well as the collisions between non-condensed particles. In the non-condensed particles dominated regime we observe strong damping of the oscillations due to inelastic collisions, equilibrating the system leading to an effective loss of details of the initial conditions. In addition, we predict that an initially self-trapped BEC state will be destroyed by these fast dynamics. The time evolution of a coherent state released at the center of a two dimensional optical lattice shows a ballistic expansion with a decreasing expansion velocity for increasing two-body interactions strength and particle number. Additionally, we predict that if the two-body interactions strength exceeds a certain value, a forerunner splits up from the expanding coherent state. We also observe that this system, which is prepared far from equilibrium, can evolve to a quasistationary non-equilibrium state.

  10. Lattice solitons in Bose-Einstein condensates

    International Nuclear Information System (INIS)

    Efremidis, Nikolaos K.; Christodoulides, Demetrios N.

    2003-01-01

    We systematically study the properties of lattice solitons in Bose-Einstein condensates with either attractive or repulsive atom interactions. This is done, by exactly solving the mean-field Gross-Pitaevskii equation in the presence of a periodic potential. We find new families of lattice soliton solutions that are characterized by the position of the energy eigenvalue within the associated band structure. These include lattice solitons in condensates with either attractive or repulsive atom interactions that exist in finite or semi-infinite gaps, as well as nonlinear modes that exhibit atomic population cutoffs

  11. Colored condensates deep inside neutron stars

    Directory of Open Access Journals (Sweden)

    Blaschke David

    2014-01-01

    Full Text Available It is demonstrated how in the absence of solutions for QCD under conditions deep inside compact stars an equation of state can be obtained within a model that is built on the basic symmetries of the QCD Lagrangian, in particular chiral symmetry and color symmetry. While in the vacuum the chiral symmetry is spontaneously broken, it gets restored at high densities. Color symmetry, however, gets broken simultaneously by the formation of colorful diquark condensates. It is shown that a strong diquark condensate in cold dense quark matter is essential for supporting the possibility that such states could exist in the recently observed pulsars with masses of 2 Mʘ.

  12. Resonances for coupled Bose-Einstein condensates

    International Nuclear Information System (INIS)

    Haroutyunyan, H.L.; Nienhuis, G.

    2004-01-01

    The properties of a Bose-Einstein condensate in a two-well potential can be manipulated by periodic modulation of the potential parameters. We study the effects arising from modulating the barrier height and the difference in well depth. At certain modulation frequencies the system exhibits resonances, which may show up in an enhancement of the tunneling rate between the wells. Resonances can be used to control the particle distribution over the wells. Some of the effects occurring in the two-well system also arise for a Bose-Einstein condensate in an optical lattice

  13. Quark Condensate in the Strange Matter

    Institute of Scientific and Technical Information of China (English)

    LU Chang-Fang; LU" Xiao-Fu

    2003-01-01

    In a nonlinear chiral SU(3) framework, we investigate the quark condensate in the strange matter including N, Σ, Ξ, and Λ, making use of chiral symmetry spontaneous breaking Lagrangian and mean-field approximation. The results show that the chiral symmetry is restored partially when the strange matter density increases and that 〈π→2〉 plays a very important role in the strange matter which may approach the constituents of the neutron stars. In addition, we can find that the strange matter density where the π-condensate emerges leads to the ratio of the nucleon number to baryon number.

  14. Experimental Investigation of Flow Condensation in Microgravity

    Science.gov (United States)

    Lee, Hyoungsoon; Park, Ilchung; Konishi, Christopher; Mudawar, Issam; May, Rochelle I.; Juergens, Jeffery R.; Wagner, James D.; Hall, Nancy R.; Nahra, Henry K.; Hasan, Mohammed M.; hide

    2013-01-01

    Future manned missions to Mars are expected to greatly increase the space vehicle's size, weight, and heat dissipation requirements. An effective means to reducing both size and weight is to replace single-phase thermal management systems with two-phase counterparts that capitalize upon both latent and sensible heat of the coolant rather than sensible heat alone. This shift is expected to yield orders of magnitude enhancements in flow boiling and condensation heat transfer coefficients. A major challenge to this shift is a lack of reliable tools for accurate prediction of two-phase pressure drop and heat transfer coefficient in reduced gravity. Developing such tools will require a sophisticated experimental facility to enable investigators to perform both flow boiling and condensation experiments in microgravity in pursuit of reliable databases. This study will discuss the development of the Flow Boiling and Condensation Experiment (FBCE) for the International Space Station (ISS), which was initiated in 2012 in collaboration between Purdue University and NASA Glenn Research Center. This facility was recently tested in parabolic flight to acquire condensation data for FC-72 in microgravity, aided by high-speed video analysis of interfacial structure of the condensation film. The condensation is achieved by rejecting heat to a counter flow of water, and experiments were performed at different mass velocities of FC-72 and water and different FC-72 inlet qualities. It is shown that the film flow varies from smooth-laminar to wavy-laminar and ultimately turbulent with increasing FC-72 mass velocity. The heat transfer coefficient is highest near the inlet of the condensation tube, where the film is thinnest, and decreases monotonically along the tube, except for high FC-72 mass velocities, where the heat transfer coefficient is enhanced downstream. This enhancement is attributed to both turbulence and increased interfacial waviness. One-ge correlations are shown to

  15. Millstone 3 condensate dissolved gas monitoring

    International Nuclear Information System (INIS)

    Burns, T.F.; Grondahl, E.E.; Snyder, D.T.

    1988-01-01

    Condensate dissolved oxygen problems at Millstone Point Unit 3 (MP3) were investigated using the Dissolved Gas Monitoring System developed by Radiological and Chemical Technology, Inc. under EPRI sponsorship. Argon was injected into the turbine exhaust basket tips to perform a dissolved gas transport analysis and determine steam jet air ejector gas removal efficiency. The operating configuration of the steam jet air ejector system was varied to determine the effect on gas removal efficiency. Following circulating water chlorination, the gas removal efficiency was determined to evaluate the effect of condenser tube fouling on steam jet air ejector performance

  16. Hysteretic capillary condensation in a porous material

    International Nuclear Information System (INIS)

    Lilly, M.P.; Hallock, R.B.

    1995-01-01

    The authors report on the behavior of hysteresis subloops in the capillary condensation of 4 He in the porous material Nuclepore. For hysteretic systems composed of many independent elements, the Preisach model may be used to predict the behavior of the resulting hysteresis. One prediction is that subloops with common chemical potential endpoints will be congruent. The observations of such subloops show that the prediction of congruence fails for this capillary condensation system. To understand deviations from Preisach behavior the authors modify the model to account for intersections among the pores. The modified model is in close agreement with the experimental results

  17. Modulation of capillary condensation by trace component

    Directory of Open Access Journals (Sweden)

    Shiqi Zhou

    2011-06-01

    Full Text Available Impact of trace component on capillary condensation (CC is investigated systematically using a classical density functional theory. It is discovered that (i presence of the trace component makes the CC to occur at much lower condensation pressure than when its absence; (ii Lennard-Jones potential parameters like size parameter and energy parameter of the trace component, and its concentration in the bulk adsorption system, show their effects the most remarkably within a particular range beyond which the effects eventually become insignificant. The present discoveries have implications in low pressure storage of gases, separation and enrichment of low concentration component, and easy control of CC transition, etc.

  18. Bose-condensation through resonance decay

    International Nuclear Information System (INIS)

    Ornik, U.; Pluemer, M.; Strottman, D.

    1993-04-01

    We show that a system described by an equation of state which contains a high number of degrees of freedom (resonances) can create a considerable amount of superfluid (condensed) pions through the decay of short-lived resonances, if baryon number and entropy are large and the dense matter decouples from chemical equilibrium earlier than from thermal equilibrium. The system cools down faster in the presence of a condensate, an effect that may partially compensate the enhancement of the lifetime expected in the case of quark-gluon-plasma formation. (orig.). 3 figs

  19. Intermolecular interactions in the condensed phase

    DEFF Research Database (Denmark)

    Christensen, Anders S.; Kromann, Jimmy Charnley; Jensen, Jan Halborg

    2017-01-01

    To facilitate further development of approximate quantum mechanical methods for condensed phase applications, we present a new benchmark dataset of intermolecular interaction energies in the solution phase for a set of 15 dimers, each containing one charged monomer. The reference interaction energy...... and solution phases. As most approximate QM methods are parametrized and evaluated using data measured or calculated in the gas phase, the dataset represents an important first step toward calibrating QM based methods for application in the condensed phase where polarization and exchange repulsion need...

  20. Pion condensation in symmetric nuclear matter

    International Nuclear Information System (INIS)

    Shamsunnahar, T.; Saha, S.; Kabir, K.; Nath, L.M.

    1991-01-01

    We have investigated the possibility of pion condensation in symmetric nuclear matter using a model of pion-nucleon interaction based essentially on chiral SU(2) x SU(2) symmetry. We have found that pion condensation is not possible for any finite value of the density. Consequently, no critical opalescence phenomenon is likely to be seen in pion-nucleus scattering nor is it likely to be possible to explain the EMC effect in terms of an increased number of pions in the nucleus. (author)

  1. Method for immobilizing invertase by adsorption on Dowex® anionic exchange resin Método para a imobilização da invertase por adsorção em resinas trocadoras de ânions (DOWEX

    Directory of Open Access Journals (Sweden)

    Ester Junko Tomotani

    2006-06-01

    Full Text Available This communication describes a method for adsorbing the invertase (EC.3.2.1.26 on DOWEX® anion exchange resin. Among the types of DOWEX® resins studied (1x8:50-400; 1x4:50-400 and 1x2:100-400, 1X4-200 was the most suitable, because it adsorbed the invertase molecules completely and the complex 1X4-200/invertase retained 100% of the catalytic activity. Moreover, no leakage of enzyme from the support was noted at the end of the sucrose hydrolysis.O presente trabalho descreve um método de adsorção da invertase (EC. 3.2.1.26 na resina de troca aniônica do tipo Dowex®. Entre os tipos de resinas Dowex® estudados (1x8:50-400; 1x4:50-400 e 1x2:100-400, 1x4-200 foi a mais apropriada devido à completa adsorção das moléculas de invertase e a sua retenção de atividade catalítica de 100% do complexo 1x4-200/invertase. Salienta-se ainda a ausência do desprendimento da enzima do suporte após o término da hidrólise da sacarose.

  2. Gravitationally Driven Wicking for Enhanced Condensation Heat Transfer.

    Science.gov (United States)

    Preston, Daniel J; Wilke, Kyle L; Lu, Zhengmao; Cruz, Samuel S; Zhao, Yajing; Becerra, Laura L; Wang, Evelyn N

    2018-04-17

    Vapor condensation is routinely used as an effective means of transferring heat or separating fluids. Filmwise condensation is prevalent in typical industrial-scale systems, where the condensed fluid forms a thin liquid film due to the high surface energy associated with many industrial materials. Conversely, dropwise condensation, where the condensate forms discrete liquid droplets which grow, coalesce, and shed, results in an improvement in heat transfer performance of an order of magnitude compared to filmwise condensation. However, current state-of-the-art dropwise technology relies on functional hydrophobic coatings, for example, long chain fatty acids or polymers, which are often not robust and therefore undesirable in industrial conditions. In addition, low surface tension fluid condensates, such as hydrocarbons, pose a unique challenge because common hydrophobic condenser coatings used to shed water (with a surface tension of 73 mN/m) often do not repel fluids with lower surface tensions (condensation heat transfer using gravitationally driven flow through a porous metal wick, which takes advantage of the condensate's affinity to wet the surface and also eliminates the need for condensate-phobic coatings. The condensate-filled wick has a lower thermal resistance than the fluid film observed during filmwise condensation, resulting in an improved heat transfer coefficient of up to an order of magnitude and comparable to that observed during dropwise condensation. The improved heat transfer realized by this design presents the opportunity for significant energy savings in natural gas processing, thermal management, heating and cooling, and power generation.

  3. Avaliação em MEV da fenda resultante da contração de polimerização da resina composta aplicada sobre diferentes materiais protetores pulpares = A sem evaluation of the gap resulting from the polymerization shrinkage of composite resins applied to different pulp protective materials

    Directory of Open Access Journals (Sweden)

    Unfer, Daniele Taís

    2006-01-01

    Full Text Available Introdução: A resina composta sofre contração como resultado da reação de polimerização que pode deslocar os materiais protetores pulpares, caso estes apresentem deficiente ou nenhuma adesão a dentina. Objetivo: avaliar o comportamento de dois materiais de proteção pulpar (CIV e CaOH2 cement em relação presença de fenda, quando submetidos a estresse de contração da resina composta e avaliar a fenda resultante da contração de polimerização entre dentina e resina composta. Metodologia: Foram confeccionados preparos classe V nas faces vestibular e lingual de 12 dentes molares humanos os quais foram divididos em quatro grupos de estudo, conforme a técnica restauradora e os materiais utilizados: G1 (SA + RC; G2 (HC + SA + RC; G3 (CIV + SA + RC e G4 (HC + CIV + SA + RC. Os corpos de prova foram avaliados em MEV e os dados obtidos foram submetidos análise não-paramétrica. Resultados: Os resultados obtidos mostram que os materiais de proteção pulpar utilizados são deslocados pela contração gerada pela polimerização da resina composta. Os melhores resultados (não presença de fenda foram demonstrados no grupo em que o sistema adesivo foi o único material entre a dentina e a resina composta. Quando do uso do CIV e do HC, associados ou não, foi encontrado o maior percentual de fendas. Conclusão: Os materiais de proteção pulpar continuarão a ser deslocados pela contração de polimerização das resinas compostas enquanto sua união à estrutura dental não apresentar suficiente resistência ou não se evitar a contração da resina composta

  4. Avaliação da interação entre resina composta e diferentes adesivos dentinários Evaluation of the interaction between composite resin and different dentin adhesives

    Directory of Open Access Journals (Sweden)

    Luciana Lourenço RIBEIRO

    1999-01-01

    Full Text Available O objetivo deste estudo foi avaliar a resistência à tração de quatro diferentes sistemas adesivos. Scotchbond Multi Purpose Plus, 3M (Grupo 1, Prime & Bond 2.0, Dentsply (Grupo 2 ProBOND, Dentsply (Grupo 3, PAAMA 2, (Grupo 4 foram usados com a resina composta Glacier (SDI. Um grupo sem a utilização de qualquer sistema adesivo serviu como controle (Grupo 5. Cinqüenta espécimes foram divididos em cinco grupos com dez espécimes cada. Uma matriz de aço inoxidável com 6,0 mm de diâmetro e 1,0 mm de profundidade foi usada para se obterem dois discos de resina composta. A resina composta foi inserida em uma metade da matriz em pequenas porções e fotopolimerizada por 40 segundos. Os adesivos foram então aplicados na superfície dos discos de resina, seguindo a instrução dos fabricantes. A segunda parte da matriz foi colocada em posição e preenchida com a resina composta. Após uma hora, a matriz foi adaptada em um dispositivo especial na máquina de ensaios Kratos para determinar a resistência de união, a uma velocidade de 0,05 mm/min. Os resultados, expressos em kgf, foram: Grupo 1 (3,99 ± 1,47, Grupo 2 (4,24 ± 2,00, Grupo 3 (3,84 ± 0,88, Grupo 4 (4,33 ± 1,23 e Grupo 5 (4,21 ± 1,38. Os resultados foram analisados pelo teste estatístico ANOVA a um critério. Não houve diferença estatisticamente significante (p The purpose of this study was to evaluate the tensile bond strength of four different adhesive systems. Scotchbond Multi-Purpose Plus, 3M (Group 1, Prime & Bond 2.0, Dentsply (Group 2, ProBOND, Dentsply (Group 3, PAAMA 2, SDI (Group 4 were used with GLACIER (SDI composite resin. One group without any adhesive was used as control (Group 5. Fifty specimens were divided into 5 groups of 10 each. A stainless steel split matrix with 6.00 mm diameter and 1.00 mm depth was used to obtain two discs of composite resin. The composite resin was applied into one half of the matrix in small portions and light cured for 40 seconds

  5. Condensation Enhancement by Surface Porosity: Three-Stage Mechanism.

    Science.gov (United States)

    Yarom, Michal; Marmur, Abraham

    2015-08-18

    Surface defects, such as pores, cracks, and scratches, are naturally occurring and commonly found on solid surfaces. However, the mechanism by which such imperfections promote condensation has not been fully explored. In the current paper we thermodynamically analyze the ability of surface porosity to enhance condensation on a hydrophilic solid. We show that the presence of a surface-embedded pore brings about three distinct stages of condensation. The first is capillary condensation inside the pore until it is full. This provides an ideal hydrophilic surface for continuing the condensation. As a result, spontaneous condensation and wetting can be achieved at lower vapor pressure than on a smooth surface.

  6. Condensate fraction in superfluid 4He

    International Nuclear Information System (INIS)

    Olinto, A.C.

    1986-01-01

    Recently, a relationship between the chemical potential and the condensate fraction η o (T) has been derived for all temperatures in the superfluid region. An analysis of liquid 4 He chemical potential data yields η o (T=0) = 0.062 and η o (T) is in excellent with the empirical results of Svensson, Sears, and Griffin. (Autor) [pt

  7. Production of clean gasoline from the condensate

    Directory of Open Access Journals (Sweden)

    Noureddin Bentahar

    2013-12-01

    Full Text Available The locally available Algerian bentonite is explored to prepare catalysts for the isomerization of the light fractions of Algerian condensate to produce high quality gasoline of high octane number. Satisfying results are obtained which render these catalysts applicable for a large scale production.

  8. A transport-based condensed history algorithm

    International Nuclear Information System (INIS)

    Tolar, D. R. Jr.

    1999-01-01

    Condensed history algorithms are approximate electron transport Monte Carlo methods in which the cumulative effects of multiple collisions are modeled in a single step of (user-specified) path length s 0 . This path length is the distance each Monte Carlo electron travels between collisions. Current condensed history techniques utilize a splitting routine over the range 0 le s le s 0 . For example, the PEnELOPE method splits each step into two substeps; one with length ξs 0 and one with length (1 minusξ)s 0 , where ξ is a random number from 0 0 is fixed (not sampled from an exponential distribution), conventional condensed history schemes are not transport processes. Here the authors describe a new condensed history algorithm that is a transport process. The method simulates a transport equation that approximates the exact Boltzmann equation. The new transport equation has a larger mean free path than, and preserves two angular moments of, the Boltzmann equation. Thus, the new process is solved more efficiently by Monte Carlo, and it conserves both particles and scattering power

  9. Free convective condensation in a vertical enclosure

    Energy Technology Data Exchange (ETDEWEB)

    Fox, R.J.; Peterson, P.F. [Univ. of California, Berkeley, CA (United States); Corradini, M.L.; Pernsteiner, A.P. [Univ. of Wisconsin, Madison, WI (United States)

    1995-09-01

    Free convective condensation in a vertical enclosure was studied numerically and the results were compared with experiments. In both the numerical and experimental investigations, mist formation was observed to occur near the cooling wall, with significant droplet concentrations in the bulk. Large recirculation cells near the end of the condensing section were generated as the heavy noncondensing gas collecting near the cooling wall was accelerated downward. Near the top of the enclosure the recirculation cells became weaker and smaller than those below, ultimately disappearing near the top of the condenser. In the experiment the mist density was seen to be highest near the wall and at the bottom of the condensing section, whereas the numerical model predicted a much more uniform distribution. The model used to describe the formation of mist was based on a Modified Critical Saturation Model (MCSM), which allows mist to be generated once the vapor pressure exceeds a critical value. Equilibrium, nonequilibrium, and MCSM calculations were preformed, showing the experimental results to lie somewhere in between the equilibrium and nonequilibrium predictions of the numerical model. A single adjustable constant (indicating the degree to which equilibrium is achieved) is used in the model in order to match the experimental results.

  10. A digital reader for condenser ionization chambers

    International Nuclear Information System (INIS)

    Stuermer, K.

    1978-01-01

    A reader for condenser chambers is described which has a completely automatic reading/charging operation, a modern digital readout presentation, and two full decades of exposure readout for each dosimeter type. The calibration and operation of the instrument are given

  11. 242-A evaporator vacuum condenser system

    International Nuclear Information System (INIS)

    Smith, V.A.

    1994-01-01

    This document is written for the 242-A evaporator vacuum condenser system (VCS), describing its purpose and operation within the evaporator. The document establishes the operating parameters specifying pressure, temperature, flow rates, interlock safety features and interfacing sub-systems to support its operation

  12. Capillary Condensation in Pores with Rough Walls:

    Czech Academy of Sciences Publication Activity Database

    Bryk, P.; Rżysko, W.; Malijevský, Alexandr; Sokołowski, S.

    2007-01-01

    Roč. 313, č. 1 (2007), s. 41-52 ISSN 0021-9797 Grant - others:TOK(XE) 509249 Institutional research plan: CEZ:AV0Z40720504 Source of funding: R - rámcový projekt EK Keywords : adsorption * pore * capillary condensation Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.309, year: 2007

  13. Orientifold Planar Equivalence: The Chiral Condensate

    DEFF Research Database (Denmark)

    Armoni, Adi; Lucini, Biagio; Patella, Agostino

    2008-01-01

    The recently introduced orientifold planar equivalence is a promising tool for solving non-perturbative problems in QCD. One of the predictions of orientifold planar equivalence is that the chiral condensates of a theory with $N_f$ flavours of Dirac fermions in the symmetric (or antisymmetric...

  14. Condensation and frost formation in heat exchangers

    International Nuclear Information System (INIS)

    Rostami, A.A.

    1982-01-01

    The occurence of condensation and of frost formation are considered for air to heat exchangers with emphasis on how such occurrences would affect the performance of such heat exchangers when they are used in ventilating applications. The formulations which predict performance are developed for parallel, counter flow and cross flow with either formation or condensation, and for condensation the consequences for evaporation of condensate and of the effect of longitudinal conduction in the walls of the exchanger are also considered. For the prediction of the exchanger performance with frost formation there must be specified the growth of the frost layer with time and existing theories for this growth are examined, a new method of calculation of the growth is presented and this is shown to give results for the growth that are in accord with available experimental evidence. This new theory for the growth of a frost layer is used to predict the performance of a parallel flow exchanger under conditions in which frost formation occurs, by successively applying the steady state performance calculation for time increments over which the frost layer build-up is calculated for these time increments. The calculation of counter flow exchanger performance by this method, while feasible, is so time consuming that only the general aspects of the calculation are considered

  15. Cloud condensation nuclei from biomass burning

    International Nuclear Information System (INIS)

    Rogers, C.F.; Hudson, J.G.; Zielinska, B.; Tanner, R.L.; Hallett, J.; Watson, J.G.

    1991-01-01

    In this work, the authors have analyzed biomass and crude oil smoke samples for ionic and organic species. The cloud condensation nuclei activities of the smoke particles are discussed in terms of the measured chemical compositions of the smoke samples. The implications of biomass burning to global climatic change are discussed

  16. Implanted muon studies in condensed matter science

    International Nuclear Information System (INIS)

    Cox, S.F.J.

    1986-12-01

    The paper reviews the broad range of applications of implanted muons in condensed matter. Muon spin rotation is discussed, along with the studies in magnetism, muonion, metals and organic radicals. A description of muon spin relaxation is also given, as well as techniques and applications appropriate to pulsed muon sources. (UK)

  17. Avalanches in a Bose-Einstein condensate

    NARCIS (Netherlands)

    Schuster, J.; Marte, A.; Amtage, S.; Sang, B.; Rempe, G.; Beijerinck, H.C.W.

    2001-01-01

    Collisional avalanches are identified to be responsible for an 8-fold increase of the initial loss rate of a large 87Rb condensate. We show that the collisional opacity of an ultracold gas exhibits a critical value. When exceeded, losses due to inelastic collisions are substantially enhanced. Under

  18. Condensation of vapor bubble in subcooled pool

    Science.gov (United States)

    Horiuchi, K.; Koiwa, Y.; Kaneko, T.; Ueno, I.

    2017-02-01

    We focus on condensation process of vapor bubble exposed to a pooled liquid of subcooled conditions. Two different geometries are employed in the present research; one is the evaporation on the heated surface, that is, subcooled pool boiling, and the other the injection of vapor into the subcooled pool. The test fluid is water, and all series of the experiments are conducted under the atmospheric pressure condition. The degree of subcooling is ranged from 10 to 40 K. Through the boiling experiment, unique phenomenon known as microbubble emission boiling (MEB) is introduced; this phenomenon realizes heat flux about 10 times higher than the critical heat flux. Condensation of the vapor bubble is the key phenomenon to supply ambient cold liquid to the heated surface. In order to understand the condensing process in the MEB, we prepare vapor in the vapor generator instead of the evaporation on the heated surface, and inject the vapor to expose the vapor bubble to the subcooled liquid. Special attention is paid to the dynamics of the vapor bubble detected by the high-speed video camera, and on the enhancement of the heat transfer due to the variation of interface area driven by the condensation.

  19. Amorphous bimetallic alloys prepared by steam condensation

    International Nuclear Information System (INIS)

    Drago, V.

    1988-01-01

    Amorphous alloys of MnSn are prepared by steam condensation, in a substratum with a temperature near of the liquid helium. The magnetic and paramagnetic hyperfine spectrum and the ordination temperature by Moessbauer effect 119Sn are measured. A diagram of magnetic phase is proposed, basing on the measures of Moessbauer effect. (C.G.C.) [pt

  20. ISOSPIN BREAKING AND THE CHIRAL CONDENSATE.

    Energy Technology Data Exchange (ETDEWEB)

    CREUTZ, M.

    2005-07-25

    With two degenerate quarks, the chiral condensate exhibits a jump as the quark masses pass through zero. I discuss how this single transition splits into two Ising like transitions when the quarks are made non-degenerate. The order parameter is the expectation of the neutral pion field. The transitions represent long distance coherent phenomena occurring without the Dirac operator having vanishingly small eigenvalues.

  1. CONVECTION IN CONDENSIBLE-RICH ATMOSPHERES

    Energy Technology Data Exchange (ETDEWEB)

    Ding, F. [Department of the Geophysical Sciences, University of Chicago, Chicago, IL 60637 (United States); Pierrehumbert, R. T., E-mail: fding@uchicago.edu [Department of Physics, University of Oxford, Oxford OX1 3PU (United Kingdom)

    2016-05-01

    Condensible substances are nearly ubiquitous in planetary atmospheres. For the most familiar case—water vapor in Earth’s present climate—the condensible gas is dilute, in the sense that its concentration is everywhere small relative to the noncondensible background gases. A wide variety of important planetary climate problems involve nondilute condensible substances. These include planets near or undergoing a water vapor runaway and planets near the outer edge of the conventional habitable zone, for which CO{sub 2} is the condensible. Standard representations of convection in climate models rely on several approximations appropriate only to the dilute limit, while nondilute convection differs in fundamental ways from dilute convection. In this paper, a simple parameterization of convection valid in the nondilute as well as dilute limits is derived and used to discuss the basic character of nondilute convection. The energy conservation properties of the scheme are discussed in detail and are verified in radiative-convective simulations. As a further illustration of the behavior of the scheme, results for a runaway greenhouse atmosphere for both steady instellation and seasonally varying instellation corresponding to a highly eccentric orbit are presented. The latter case illustrates that the high thermal inertia associated with latent heat in nondilute atmospheres can damp out the effects of even extreme seasonal forcing.

  2. Fractional condensation of biomass pyrolysis vapors

    NARCIS (Netherlands)

    Westerhof, Roel Johannes Maria; Brilman, Derk Willem Frederik; Garcia Perez, M.; Wang, Zhouhong; Oudenhoven, Stijn; van Swaaij, Willibrordus Petrus Maria; Kersten, Sascha R.A.

    2011-01-01

    In this paper, we have investigated the possibilities to steer the composition and, thus, the quality of pyrolysis liquids by the reactor temperature and the pyrolysis vapor condenser temperature. Pine wood was pyrolyzed in a 1 kg/h fluidized-bed pyrolysis reactor operated at 330 or 480 °C. The

  3. Coherent decay of positronium bose condensate

    International Nuclear Information System (INIS)

    Vanyashin, V.S.

    1992-07-01

    The rate of self-stimulated emission of photon pairs by pseudoscalar particles from Bose condensate is calculated. Growing with density this rate exceeds the density independent rate of spontaneous two photon decay at plausible density values of positronium gas, thus opening in principle, the way to the annihilation gamma ray laser realization. (author). 2 refs

  4. The color class condensate RHIC and HERA

    CERN Document Server

    McLerran, L

    2002-01-01

    In this talk, I discuss a universal form of matter, the color glass condensate. It is this matter which composes the low x part of all hadronic wavefunctions. The experimental programs at RHIC and HERA, and future programs at LHC and RHIC may allow us to probe and study the properties of this matter. (8 refs).

  5. Condensation in a two-phase pool

    International Nuclear Information System (INIS)

    Duffey, R.B.; Hughes, E.D.

    1991-01-01

    We consider the case of vapor condensation in a liquid pool, when the heat transfer is controlled by heat losses through the walls. The analysis is based on drift flux theory for phase separation in the pool, and determines the two-phase mixture height for the pool. To our knowledge this is the first analytical treatment of this classic problem that gives an explicit result, previous work having established the result for the evaporative case. From conservation of mass and energy in a one-dimensional steady flow, together with a void relation between the liquid and vapor fluxes, we determine the increase in the mixture level from the base level of the pool. It can be seen that the thermal and hydrodynamic influences are separable. Thus, the thermal influence of the wall heat transfer appears through its effect on the condensing length L*, so that at high condensation rates the pool is all liquid, and at low rates overflows (the level swell or foaming effect). Similarly, the phase separation effect hydrodynamically determines the height via the relative velocity of the mixture to the entering flux. We examine some practical applications of this result to level swell in condensing flows, and also examine some limits in ideal cases

  6. Condensed matter studies by nuclear methods

    International Nuclear Information System (INIS)

    Krolas, K.; Tomala, K.

    1988-01-01

    The separate abstract was prepared for 1 of the papers in this volume. The remaining 13 papers dealing with the use but not with advances in the use of nuclear methods in studies of condensed matter, were considered outside the subject scope of INIS. (M.F.W.)

  7. Vast Antimatter Regions and Scalar Condensate Baryogenesis

    OpenAIRE

    Kirilova, D.; Panayotova, M.; Valchanov, T.

    2002-01-01

    The possibility of natural and abundant creation of antimatter in the Universe in a SUSY-baryogenesis model with a scalar field condensate is described. This scenario predicts vast quantities of antimatter, corresponding to galaxy and galaxy cluster scales today, separated from the matter ones by baryonically empty voids. Theoretical and observational constraints on such antimatter regions are discussed.

  8. Scalar Condensation of Holographic Superconductors using ...

    Indian Academy of Sciences (India)

    Abstract. We study holographic superconductors analytically by using the Ginzburg–Landau action with the γ-quartic term | |4. Our results show that γ-term plays a role in the scalar condensation. It is found that the system displays two kinds of critical temperatures. One is independent of γ. But the other increases with ...

  9. Estimating Spring Condensation on the Great Lakes

    Science.gov (United States)

    Meyer, A.; Welp, L.

    2017-12-01

    The Laurentian Great Lakes region provides opportunities for shipping, recreation, and consumptive water use to a large part of the United States and Canada. Water levels in the lakes fluctuate yearly, but attempts to model the system are inadequate because the water and energy budgets are still not fully understood. For example, water levels in the Great Lakes experienced a 15-year low period ending in 2013, the recovery of which has been attributed partially to decreased evaporation and increased precipitation and runoff. Unlike precipitation, the exchange of water vapor between the lake and the atmosphere through evaporation or condensation is difficult to measure directly. However, estimates have been constructed using off-shore eddy covariance direct measurements of latent heat fluxes, remote sensing observations, and a small network of monitoring buoys. When the lake surface temperature is colder than air temperature as it is in spring, condensation is larger than evaporation. This is a relatively small component of the net annual water budget of the lakes, but the total amount of condensation may be important for seasonal energy fluxes and atmospheric deposition of pollutants and nutrients to the lakes. Seasonal energy fluxes determine, and are influenced by, ice cover, water and air temperatures, and evaporation in the Great Lakes. We aim to quantify the amount of spring condensation on the Great Lakes using the National Center for Atmospheric Prediction North American Regional Reanalysis (NCEP NARR) Data for Winter 2013 to Spring 2017 and compare the condensation values of spring seasons following high volume, high duration and low volume, low duration ice cover.

  10. Condensation shocks in high momentum two-phase flows in condensing injectors

    International Nuclear Information System (INIS)

    Anand, G.; Christensen, R.N.

    1993-01-01

    This study presents a phenomenological and mathematical model of condensation shocks in high momentum two-phase flows in condensing injectors. The characteristics of the shock were related to the mode of vapor bubble collapse. Using cavitation terminology, the bubble collapse can be classified as inertially controlled or thermally controlled. Inertial bubble collapse occurs rapidly whereas, a thermally controlled collapse results in a significantly longer collapse time. The interdependence between the bubble collapse mode and the momentum and pressure of the flow, was analyzed in this study. For low-temperature-high-velocity flows a steep pressure rise with complete condensation was obtained. For a high-temperature-low velocity flow with noncondensables, low pressure recovery with incomplete condensation was observed. These trends are in agreement with previous experimental observations

  11. Condensation: Passenger Not Driver in Atmospheric Thermodynamics

    Directory of Open Access Journals (Sweden)

    Jack Denur

    2016-11-01

    Full Text Available The second law of thermodynamics states that processes yielding work or at least capable of yielding work are thermodynamically spontaneous, and that those costing work are thermodynamically nonspontaneous. Whether a process yields or costs heat is irrelevant. Condensation of water vapor yields work and hence is thermodynamically spontaneous only in a supersaturated atmosphere; in an unsaturated atmosphere it costs work and hence is thermodynamically nonspontaneous. Far more of Earth’s atmosphere is unsaturated than supersaturated; based on this alone evaporation is far more often work-yielding and hence thermodynamically spontaneous than condensation in Earth’s atmosphere—despite condensation always yielding heat and evaporation always costing heat. Furthermore, establishment of the unstable or at best metastable condition of supersaturation, and its maintenance in the face of condensation that would wipe it out, is always work-costing and hence thermodynamically nonspontaneous in Earth’s atmosphere or anywhere else. The work required to enable supersaturation is most usually provided at the expense of temperature differences that enable cooling to below the dew point. In the case of most interest to us, convective weather systems and storms, it is provided at the expense of vertical temperature gradients exceeding the moist adiabatic. Thus, ultimately, condensation is a work-costing and hence thermodynamically nonspontaneous process even in supersaturated regions of Earth’s or any other atmosphere. While heat engines in general can in principle extract all of the work represented by any temperature difference until it is totally neutralized to isothermality, convective weather systems and storms in particular cannot. They can extract only the work represented by partial neutralization of super-moist-adiabatic lapse rates to moist-adiabaticity. Super-moist-adiabatic lapse rates are required to enable convection of saturated air

  12. Bubbler condenser related research work. Present situation

    International Nuclear Information System (INIS)

    2001-02-01

    Intensive discussions within the OECD Support Group on 'VVER-440 Bubbler Condenser Containment Research Work' between 1991 and 1994 demonstrated the need for supplementary research work to achieve an adequate level of basic knowledge. In 1994, the European Commission (EC) asked for a specific 'VVER-440/213 Bubble Condenser Qualification Feasibility Study', which was finished early in 1996, confirming the need for additional research in this field. The Feasibility study formed the basis for the Bubble Condenser Experimental Qualification Project (BCEQ) with two separate experimental activities to be executed within the frame of the PHARE/TACIS 2.13/95 project of the European Commission. A first activity served to study the thermal-hydraulic phenomena and the associated structure dynamic interactions. This part of the project was performed at EREC, in Elektrogorsk, Russia. The design of the test facility was based on the prototypical bubbler condenser configuration for the Hungarian Paks nuclear power plant. A second activity addressed the structural integrity of certain components of the bubbler condenser steel structures under DBA-typical conditions. This part of the project was performed at VUEZ, in Levice, Slovak Republic. The design of the components of this facility was based on the structural properties of the Dukovany and/or Bohunice nuclear power plants. A third component of the BCEQ project was specified later asking for analytical studies, which should be supported by a number of small-scale separate effects tests to be performed at SVUSS, in Bechovice, Czech Republic. The main experimental and analytical results of the BCEQ test campaigns have been presented and discussed within the frame of the 4. meeting of the Technical Advisory Committee to the BCEQ (Bubble Condenser Experimental Qualification) Project in Brussels in December 1999 and on occasion of the 11. OECD Support Group Meeting in Berlin in April 2000. The discussions had evidenced several

  13. Mixed fermion-photon condensate in strongly coupled quantum electrodynamics

    International Nuclear Information System (INIS)

    Gusynin, V.P.; Kushnir, V.A.

    1989-01-01

    The existence of a new mixed fermion-photon condensate breaking chiral symmetry in strongly coupled phase of quantum electrodynamics is shown. An analytical expression for the renormalized condensate is obtained. 20 refs.; 2 figs

  14. Hysteretic capillary condensation of 4He on Nuclepore substrates

    International Nuclear Information System (INIS)

    Godshalk, K.M.; Smith, D.T.; Hallock, R.B.

    1987-01-01

    Measurements of the approach to capillary condensation and the hysteresis encountered in capillary condensation are reported for helium adsorbed on the polycarbonate substrate Nuclepore. (Author) (5 refs., 3 figs.)

  15. Transient direct-contact condensation on liquid droplets

    International Nuclear Information System (INIS)

    Pasamehmetoglu, K.O.; Nelson, R.A.

    1987-01-01

    In this paper, direct-contact condensation on subcooled liquid droplets is studied in two parts. In the first part, simple design correlations for the condensation in a steady environment are developed based upon a conduction model. These correlations include the convective heat-transfer coefficient, condensation rate, total condensation, and the droplet-thermalization time. In the second part of the paper, the effect of a time-dependent saturation temperature on the condensation process is investigated. A rapid decrease in saturation temperature is typical of condensation environments in which the steam-supply rate is limited and condensation-induced depressurization becomes important. Design correlations are developed for condensation in an environment in which the saturation temperature decreases linearly with time. These correlations are graphically compared to the design correlations of the first part through a quasi-steady approach. The error associated with this approach is quantified as a function of the rate of change of the saturation temperature

  16. Refrigeration. Heat Transfer. Part I: Evaporators and Condensers

    DEFF Research Database (Denmark)

    Knudsen, Hans-Jørgen Høgaard

    2002-01-01

    The note gives an introduction to heat transfer with phase shift. Pool Boiling, Flow Boiling, Condensation.......The note gives an introduction to heat transfer with phase shift. Pool Boiling, Flow Boiling, Condensation....

  17. O Impacto das Resinas na Economia: Principais Indicadores Econômicos The Impact of Resins on the Economy: Key Economic Indicators

    Directory of Open Access Journals (Sweden)

    Suzana Borschiver

    2002-01-01

    Full Text Available Este artigo tem como objetivo principal proporcionar o conhecimento para a compreensão do impacto da indústria química na economia brasileira. Para tanto, utiliza-se como uma das ferramentas essenciais o Sistema de Contas Nacionais (SCN do IBGE (Instituto Brasileiro de Geografia e Estatística, órgão federal produtor de estatísticas oficiais. Este sistema, através das suas Tabelas de Recursos e Usos, possibilita a geração de informações importantes para tomadas de decisões de empresas, governo e universidades/centros de pesquisa, através de uma visão econômica de produtos e atividades que fazem parte do sistema produtivo do país. No caso deste artigo, utiliza-se como exemplo o grupo das resinas, procurando-se demonstrar, seja pela ótica da oferta ou da demanda, o impacto destas na economia brasileira, através de alguns indicadores econômicos tais como: produção, consumo intermediário e importação.This article is aimed at analysing the impact of chemical industries on the Brazilian economy. One of essential tools for doing that in the Sistema de Contas Nacionais (System of National Accounts -- SCN of the Instituto Brasileiro de Geografia e Estatística -- IBGE, the official federal statistics agency. The Input and Out-Put Tables in this system make it possible to generate information that can support the decision-making processes of companies, governments and universities/research centers, through providing an economic view of products and activities that comprise the country's production system. In this article, RESINS are the subject of analysis. Their impact on the Brazilian economy will be demonstrated, both from a supply and demand viewpoint, using a number of economic indicators, such as production, intermediate consumption and imports.

  18. Method and apparatus for controlled condensation isotope separation

    International Nuclear Information System (INIS)

    Sullivan, J.A.; Lee, J.T. Jr.; Kim, K.C.

    1981-01-01

    The invention provides a method for producing controlled homogeneous condensation of a molecular feed gas containing several isotopes. The feed gas flows at supersonic rates through an expansion nozzle under conditions at which the gas would normally condense. The gas is irradiated with laser radiation of a wavelength that selectively excites those molecules in the feed gas that contain a particular isotope, thus preventing their condensation. Condensate particles may be aerodynamically separated from the flowing gas stream

  19. 21 CFR 573.200 - Condensed animal protein hydrolysate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Condensed animal protein hydrolysate. 573.200... ANIMALS Food Additive Listing § 573.200 Condensed animal protein hydrolysate. (a) Identity. The condensed animal protein hydrolysate is produced from the meat byproducts scraped from cured (salted) hides taken...

  20. 21 CFR 886.1380 - Diagnostic condensing lens.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Diagnostic condensing lens. 886.1380 Section 886...) MEDICAL DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1380 Diagnostic condensing lens. (a) Identification. A diagnostic condensing lens is a device used in binocular indirect ophthalmoscopy (a procedure...

  1. Scattering of atoms on a Bose-Einstein condensate

    International Nuclear Information System (INIS)

    Poulsen, Uffe V.; Moelmer, Klaus

    2003-01-01

    We study the scattering properties of a Bose-Einstein condensate held in a finite depth well when the incoming particles are identical to the ones in the condensate. We calculate phase shifts and corresponding transmission and reflection coefficients, and we show that the transmission times can be negative, i.e., the atomic wave packet seemingly leaves the condensate before it arrives

  2. Interference of an array of independent Bose-Einstein condensates

    International Nuclear Information System (INIS)

    Hadzibabic, Zoran; Stock, Sabine; Battelier, Baptiste; Bretin, Vincent; Dalibard, Jean

    2004-01-01

    We have observed high-contrast matter wave interference between 30 Bose-Einstein condensates with uncorrelated phases. Interferences were observed after the independent condensates were released from a one-dimensional optical lattice and allowed to overlap. This phenomenon is explained with a simple theoretical model, which generalizes the analysis of the interference of two condensates

  3. Evaporation and Condensation Flows of a Vapor-Gas Mixture from or onto the Condensed Phase with an Internal Structure

    National Research Council Canada - National Science Library

    Onishi, Yoshimoto; Yamada, Ken

    2005-01-01

    Transient motions of a vapor-gas mixture due to the evaporation and condensation processes from or onto the plane condensed phase, with a temperature field as its internal structure, have been studied...

  4. Comparison of chemical composition of packable resin composites by scanning electron microscopy Comparação da composição química de resinas compostas compactáveis através de microscopia eletrônica de varredura

    Directory of Open Access Journals (Sweden)

    Ana Amélia Bianchi e Silva

    2005-03-01

    Full Text Available OBJECTIVES: the purpose of this study was to compare the chemical composition of four different shades (incisal/extra-light, A2, A3 and B3 of two packable resin composites (SOLITAIRE®, and PRODIGY CONDENSABLE TM. METHODS AND MATERIALS: the specimens measured 4mm in diameter and 4mm in thickness. Five specimens were made for each shade of the materials. They were light cured for 40 seconds at a power of 600mW/cm². Subsequently, the specimens were removed from the plates and ground to powder and then pressed into holes measuring 4mm in diameter in a Teflon matrix, using the plates of the same material as base and cover. Specimens were evaluated under SEM with an x-ray detector for the spectroscopic test by energy dispersing. RESULTS: the chemical components found in both materials were practically the same, but in different proportions. Carbon, Oxygen, Aluminum, Silica, Fluoride and Barium were found. CONCLUSIONS: the chemical composition of each same material varied according to each shade analyzed.OBJETIVO: comparar a composição química de duas resinas compostas compactáveis (SOLITAIRE®, Kulzer, e PRODIGY CONDENSABLE TM, Kerr em quatro diferentes cores (incisal/extra-light, A2, A3 e B3. MATERIAIS E MÉTODO: as amostras foram confeccionadas em placas de acrílico transparente com 4mm de espessura. Os materiais foram inseridos e compactados em orifícios de 4mm de diâmetro. Para cada cor de cada material foram confeccionadas 5 amostras, as quais foram fotopolimerizadas durante 40 segundos a uma potência de 600mW/cm². Logo após, estas foram removidas das placas e trituradas até apresentarem uma consistência de pó, foram prensadas, para colocação das diferentes cores em nichos de 4mm de diâmetro de uma matriz de Teflon, tendo como base e cobertura duas placas do mesmo material. As amostras foram montadas em stubs para a metalização, ou deposição de íons, sendo suas imagens importadas ao microscópio eletrônico de varredura com

  5. Bose-Einstein condensation and applications

    International Nuclear Information System (INIS)

    Jaksch, D.H.

    1999-10-01

    After a short introduction on recent developments in the field of Bose-Einstein condensation (BEC) with weakly interacting neutral atoms in the first part of my thesis I investigate the properties of a BEC in its stationary state with the help of quantum kinetic theory in the second part. Especially, I consider the particle number and phase fluctuations of a BEC emerging from the interaction of the condensed particles with the thermal cloud of atoms. In the third part of my thesis I show how one might realize the Bose-Hubbard model in optical lattices by making use of BEC. In the last part of my work I show how one can realize quantum logic with neutral atoms trapped in either optical lattices or in magnetic microtraps. (author)

  6. Faraday waves in Bose-Einstein condensates

    International Nuclear Information System (INIS)

    Nicolin, Alexandru I.; Carretero-Gonzalez, R.; Kevrekidis, P. G.

    2007-01-01

    Motivated by recent experiments on Faraday waves in Bose-Einstein condensates we investigate both analytically and numerically the dynamics of cigar-shaped Bose-condensed gases subject to periodic modulation of the strength of the transverse confinement. We offer a fully analytical explanation of the observed parametric resonance, based on a Mathieu-type analysis of the non-polynomial Schroedinger equation. The theoretical prediction for the pattern periodicity versus the driving frequency is directly compared to the experimental data, yielding good qualitative and quantitative agreement between the two. These results are corroborated by direct numerical simulations of both the one-dimensional non-polynomial Schroedinger equation and of the fully three-dimensional Gross-Pitaevskii equation

  7. Hydrogen behavior in ice condenser containments

    Energy Technology Data Exchange (ETDEWEB)

    Lundstroem, P.; Hongisto, O. [Power Plant Lab., Helsinki (Finland); Theofanous, T.G. [Univ. of California, Santa Barbara, CA (United States)] [and others

    1995-09-01

    A new hydrogen management strategy is being developed for the Loviisa ice condenser containment. The strategy relies on containment-wide natural circulations that develop, once the ice condenser doors are forced open, to effectively produce a well-mixed behavior, and a correspondingly slow rise in hydrogen concentration. Levels can then be kept low by a distributed catalytic recombiner system, and (perhaps) an igniter system as a backup, while the associated energy releases can be effectively dissipated in the ice bed. Verification and fine-tuning of the approach is carried out experimentally in the VICTORIA facility and by associated scaling/modelling studies. VICTORIA represents an 1/15th scale model of the Loviisa containment, hydrogen is simulated by helium, and local concentration measurements are obtained by a newly developed instrument specifically for this purpose, called SPARTA. This paper is focused on experimental results from several key experiments that provide a first delineation of key behaviors.

  8. Condensation Mechanism of Hydrocarbon Field Formation.

    Science.gov (United States)

    Batalin, Oleg; Vafina, Nailya

    2017-08-31

    Petroleum geology explains how hydrocarbon fluids are generated, but there is a lack of understanding regarding how oil is expelled from source rocks and migrates to a reservoir. To clarify the process, the multi-layer Urengoy field in Western Siberia was investigated. Based on this example, we have identified an alternative mechanism of hydrocarbon field formation, in which oil and gas accumulations result from the phase separation of an upward hydrocarbon flow. There is evidence that the flow is generated by the gases released by secondary kerogen destruction. This study demonstrates that oil components are carried by the gas flow and that when the flow reaches a low-pressure zone, it condenses into a liquid with real oil properties. The transportation of oil components in the gas flow provides a natural explanation for the unresolved issues of petroleum geology concerning the migration process. The condensation mechanism can be considered as the main process of oil field formation.

  9. Condensed tannins act against cattle nematodes

    DEFF Research Database (Denmark)

    Novobilský, Adam; Mueller-Harvey, Irene; Thamsborg, Stig Milan

    2011-01-01

    The use of natural plant anthelmintics was suggested as a possible alternative control of gastrointestinal nematodes (GIN) in ruminants. Direct anthelmintic effects of tannin-containing plants have already been shown in sheep and goat GIN. These anthelmintic properties are mainly associated...... with condensed tannins. In the present study, we evaluated possible in vitro effects of three tannin-containing plants against bovine GIN. Effects of Onobrychis viciifolia, Lotus pedunculatus and Lotus corniculatus condensed tannin (CT) extracts on Cooperia oncophora and Ostertagia ostertagi were determined...... (third stage larvae) was also affected by CT extracts from all three plants. In both in vitro assays, extracts with added polyvinylpolypyrrolidone, an inhibitor of tannins, generated almost the same values as the negative control; this confirms the role of CT in the anthelmintic effect of these plant...

  10. Bose-Einstein condensation in microgravity.

    Science.gov (United States)

    van Zoest, T; Gaaloul, N; Singh, Y; Ahlers, H; Herr, W; Seidel, S T; Ertmer, W; Rasel, E; Eckart, M; Kajari, E; Arnold, S; Nandi, G; Schleich, W P; Walser, R; Vogel, A; Sengstock, K; Bongs, K; Lewoczko-Adamczyk, W; Schiemangk, M; Schuldt, T; Peters, A; Könemann, T; Müntinga, H; Lämmerzahl, C; Dittus, H; Steinmetz, T; Hänsch, T W; Reichel, J

    2010-06-18

    Albert Einstein's insight that it is impossible to distinguish a local experiment in a "freely falling elevator" from one in free space led to the development of the theory of general relativity. The wave nature of matter manifests itself in a striking way in Bose-Einstein condensates, where millions of atoms lose their identity and can be described by a single macroscopic wave function. We combine these two topics and report the preparation and observation of a Bose-Einstein condensate during free fall in a 146-meter-tall evacuated drop tower. During the expansion over 1 second, the atoms form a giant coherent matter wave that is delocalized on a millimeter scale, which represents a promising source for matter-wave interferometry to test the universality of free fall with quantum matter.

  11. Essence of the Vacuum Quark Condensate

    International Nuclear Information System (INIS)

    Brodsky, Stanley

    2010-01-01

    We show that the chiral-limit vacuum quark condensate is qualitatively equivalent to the pseudoscalar meson leptonic decay constant in the sense that they are both obtained as the chiral-limit value of well-defined gauge-invariant hadron-to-vacuum transition amplitudes that possess a spectral representation in terms of the current-quark mass. Thus, whereas it might sometimes be convenient to imagine otherwise, neither is essentially a constant mass-scale that fills all spacetime. This means, in particular, that the quark condensate can be understood as a property of hadrons themselves, which is expressed, for example, in their Bethe-Salpeter or light-front wavefunctions.

  12. Capillary Condensation with a Grain of Salt.

    Science.gov (United States)

    Yarom, Michal; Marmur, Abraham

    2017-11-21

    Capillary condensation (CC), namely, the formation from the vapor of a stable phase of drops below the saturation pressure, is a prevalent phenomenon. It may occur inside porous structures or between surfaces of particles. CC between surfaces, a liquid "bridge", is of particular practical interest because of its resulting adhesive force. To date, studies have focused on pure water condensation. However, nonvolatile materials, such as salts and surfactants, are prevalent in many environments. In the current study, the effect of these contaminants on CC is investigated from a thermodynamic point of view. This is done by computing the Gibbs energy of such systems and developing the modified Kelvin equation, based on the Kohler theory. The results demonstrate that nonvolatile solutes may have a number of major effects, including an increase in the critical radius and the stabilization of the newly formed phase.

  13. Condensation heat transfer in plate heat exchangers

    International Nuclear Information System (INIS)

    Panchal, C.B.

    1985-01-01

    An Alfa-Laval plate heat exchanger, previously tested as an evaporator, was retested as a condenser. Two series of tests with different chevron-angle plates were carried out using ammonia as a working fluid. The overall heat-transfer coefficient and pressure drop were measured, and the effects of operating parameters were determined. The experimental data were compared with theoretical predictions. In the analysis, a gravity-controlled condensation process was modeled theoretically, and the overall performance was calculated. The analysis shows that the overall heat-transfer coefficient can be predicted with an average uncertainty of about 10%. It is, however, important to consider the interfacial shear stress, because the effective friction factor is high for flow in plate heat exchangers

  14. Bose-Einstein condensation and superfluidity

    CERN Document Server

    Pitaevskii, Lev

    2016-01-01

    This volume introduces the basic concepts of Bose–Einstein condensation and superfluidity. It makes special reference to the physics of ultracold atomic gases; an area in which enormous experimental and theoretical progress has been achieved in the last twenty years. Various theoretical approaches to describing the physics of interacting bosons and of interacting Fermi gases, giving rise to bosonic pairs and hence to condensation, are discussed in detail, both in uniform and harmonically trapped configurations. Special focus is given to the comparison between theory and experiment, concerning various equilibrium, dynamic, thermodynamic, and superfluid properties of these novel systems. The volume also includes discussions of ultracold gases in dimensions, quantum mixtures, and long-range dipolar interactions.

  15. Antiferromagnetic spinor condensates in a bichromatic superlattice

    Science.gov (United States)

    Tang, Tao; Zhao, Lichao; Chen, Zihe; Liu, Yingmei

    2017-04-01

    A spinor Bose-Einstein condensate in an optical supelattice has been considered as a good quantum simulator for understanding mesoscopic magnetism. We report an experimental study on an antiferromagnetic spinor condensate in a bichromatic superlattice constructed by a cubic red-detuned optical lattice and a one-dimensional blue-detuned optical lattice. Our data demonstrate a few advantages of this bichromatic superlattice over a monochromatic lattice. One distinct advantage is that the bichromatic superlattice enables realizing the first-order superfluid to Mott-insulator phase transitions within a much wider range of magnetic fields. In addition, we discuss an apparent discrepancy between our data and the mean-field theory. We thank the National Science Foundation and the Oklahoma Center for the Advancement of Science and Technology for financial support.

  16. Condensation induced water hammer driven sterilization

    Science.gov (United States)

    Kullberg, Craig M.

    2004-05-11

    A method and apparatus (10) for treating a fluid or materials therein with acoustic energy has a vessel (14) for receiving the fluid with inner walls shaped to focus acoustic energy to a target zone within the vessel. One or more nozzles (26) are directed into the vessel (14) for injecting a condensable vapor, such as steam, into the vessel (14). The system may include a steam source (18) for providing steam as the condensable vapor from an industrial waste heat source. Steam drums (88) are disposed between the steam source (18) and nozzles (26) to equalize and distribute the vapor pressure. A cooling source (30) provides a secondary fluid for maintaining the liquid in the vessel (14) in subcooled conditions. A heating jacket (32) surrounds the vessel (14) to heat the walls of the vessel (14) and prevent biological growth thereon. A pressurizer (33) may operate the system at elevated pressures.

  17. Condensate oscillations in a Penrose tiling lattice

    Science.gov (United States)

    Akdeniz, Z.; Vignolo, P.

    2017-07-01

    We study the dynamics of a Bose-Einstein condensate subject to a particular Penrose tiling lattice. In such a lattice, the potential energy at each site depends on the neighbour sites, accordingly to the model introduced by Sutherland [16]. The Bose-Einstein wavepacket, initially at rest at the lattice symmetry center, is released. We observe a very complex time-evolution that strongly depends on the symmetry center (two choices are possible), on the potential energy landscape dispersion, and on the interaction strength. The condensate-width oscillates at different frequencies and we can identify large-frequency reshaping oscillations and low-frequency rescaling oscillations. We discuss in which conditions these oscillations are spatially bounded, denoting a self-trapping dynamics.

  18. Laser Processed Condensing Heat Exchanger Technology Development

    Science.gov (United States)

    Hansen, Scott; Wright, Sarah; Wallace, Sarah; Hamilton, Tanner; Dennis, Alexander; Zuhlke, Craig; Roth, Nick; Sanders, John

    2017-01-01

    The reliance on non-permanent coatings in Condensing Heat Exchanger (CHX) designs is a significant technical issue to be solved before long-duration spaceflight can occur. Therefore, high reliability CHXs have been identified by the Evolvable Mars Campaign (EMC) as critical technologies needed to move beyond low earth orbit. The Laser Processed Condensing Heat Exchanger project aims to solve these problems through the use of femtosecond laser processed surfaces, which have unique wetting properties and potentially exhibit anti-microbial growth properties. These surfaces were investigated to identify if they would be suitable candidates for a replacement CHX surface. Among the areas researched in this project include microbial growth testing, siloxane flow testing in which laser processed surfaces were exposed to siloxanes in an air stream, and manufacturability.

  19. Performance characterization of isolation condenser of SBWR

    International Nuclear Information System (INIS)

    Khan, H.J.; Rohatgi, U.S.

    1992-01-01

    A systematic study of the performance of the Isolation Condenser (IC) for a conceptual design of SBWR is presented. The objective of the IC is to passively remove heat and control the pressure variation in the Reactor Pressure Vessel (RPV). According to the observed trends, the IC cooling capacity and condensate flow can independently influence the ultimate performance of the IC. The transient pressure profile for the IC reaches different equilibrium values for each of the cases analyzed. The absolute magnitude of these values are a function of the cooling capacity and flow rates. With appropriate control of the liquid flow loss coefficients, the performance of the IC can be well predicted. Due to the lack of useful data, this study is limited to the numerical simulation of the IC

  20. THE COLOUR GLASS CONDENSATE: AN INTRODUCTION

    Energy Technology Data Exchange (ETDEWEB)

    IANCU,E.; LEONIDOV,A.; MCLERRAN,L.

    2001-08-06

    In these lectures, the authors develop the theory of the Colour Glass Condensate. This is the matter made of gluons in the high density environment characteristic of deep inelastic scattering or hadron-hadron collisions at very high energy. The lectures are self contained and comprehensive. They start with a phenomenological introduction, develop the theory of classical gluon fields appropriate for the Colour Glass, and end with a derivation and discussion of the renormalization group equations which determine this effective theory.

  1. Experimental and theoretical study of reflux condensation

    Energy Technology Data Exchange (ETDEWEB)

    Bakke, Knut

    1997-12-31

    This thesis studies the separation of gas mixtures in a reflux condenser. also called a dephlegmator. Reflux condensation is separation of a gas mixture, in reflux flow with condensing liquid, under continuous heat removal. A numerical model of a dephlegmator for binary mixtures was developed. The model may readily be extended to multi-component mixtures, as the solution method is based on a matrix solver. Separation of a binary mixture in a reflux condenser test rig is demonstrated. The test facility contains a single-tube test section that was designed and built as part of the project. Test mixtures of propane and n-butane were used, and a total of 15 experiments are reported. Limited degree of separation was achieved due to limited heat transfer area and narrow boiling point range of the test mixture. The numerical model reproduces the experimental data within reasonable accuracy. Deviation between calculated and measured properties is less than 6% of the measured temperature and less than 5% of the measured flow rate. The model is based on mechanistic models of physical processes and is not calibrated or tuned to fit the experimental data. The numerical model is applied to a number of separation processes. These case studies show that the required heat transfer area increases rapidly with increments in top product composition (light component). Flooding limits the amount of reflux liquid. The dephlegmator is suitable for separation of feed mixtures that are rich in light components. The gliding temperature in the dephlegmation process enables utilization of top product as refrigerant, with subsequent energy saving as a result. 61 refs., 50 figs., 34 tabs.

  2. Dilaton, gaugino condensation and supersymmetry breaking

    International Nuclear Information System (INIS)

    Taylor, T.R.; Northeastern Univ., Boston, MA

    1990-01-01

    Non-perturbative condensation of gauginos belonging to a gauge group of the form G 1 xG 2 x...xG p , where G n are non-abelian subgroups, is examined in superstring theory by utilizing the effective lagrangian techniques. A supersymmetric vacuum with stable expectation values of the dilaton and moduli fields is shown to exist provided that the gauge group satisfies one non-trivial constraint. (orig.)

  3. Novel Quantum Condensates in Excitonic Matter

    International Nuclear Information System (INIS)

    Littlewood, P. B.; Keeling, J. M. J.; Simons, B. D.; Eastham, P. R.; Marchetti, F. M.; Szymanska, M. H.

    2009-01-01

    These lectures interleave discussion of a novel physical problem of a new kind of condensate with teaching of the fundamental theoretical tools of quantum condensed matter field theory. Polaritons and excitons are light mass composite bosons that can be made inside solids in a number of different ways. As bosonic particles, they are liable to make a phase coherent ground state - generically called a Bose-Einstein condensate (BEC) - and these lectures present some models to describe that problem, as well as general approaches to the theory. The focus is very much to explain how mean-field-like approximations that are often presented heuristically can be derived in a systematic fashion by path integral methods. Going beyond the mean field theory then produces a systematic approach to calculation of the excitation energies, and the derivation of effective low energy theories that can be generalised to more complex dynamical and spatial situations than is practicable for the full theory, as well as to study statistical properties beyond the semi-classical regime. in particular, for the polariton problem, it allows one to connect the regimes of equilibrium BEC and non-equilibrium laser. The lectures are self-sufficient, but not highly detailed. The methodological aspects are covered in standard quantum field theory texts and the presentation here is deliberately cursory: the approach will be closest to the book of Altland and Simons. Since these lectures concern a particular type of condensate, reference should also be made to texts on BEC, for example by Pitaevskii and Stringari. A recent theoretically focussed review of polariton systems covers many of the technical issues associated with the polariton problem in greater depth and provides many further references.

  4. THE COLOUR GLASS CONDENSATE: AN INTRODUCTION

    International Nuclear Information System (INIS)

    Iancu, E.; Leonidov, A.; McLerran, L.

    2001-01-01

    In these lectures, the authors develop the theory of the Colour Glass Condensate. This is the matter made of gluons in the high density environment characteristic of deep inelastic scattering or hadron-hadron collisions at very high energy. The lectures are self contained and comprehensive. They start with a phenomenological introduction, develop the theory of classical gluon fields appropriate for the Colour Glass, and end with a derivation and discussion of the renormalization group equations which determine this effective theory

  5. Bouncing cosmologies from quantum gravity condensates

    Science.gov (United States)

    Oriti, Daniele; Sindoni, Lorenzo; Wilson-Ewing, Edward

    2017-02-01

    We show how the large-scale cosmological dynamics can be obtained from the hydrodynamics of isotropic group field theory condensate states in the Gross-Pitaevskii approximation. The correct Friedmann equations are recovered in the classical limit for some choices of the parameters in the action for the group field theory, and quantum gravity corrections arise in the high-curvature regime causing a bounce which generically resolves the big-bang and big-crunch singularities.

  6. Bose-Einstein condensation of paraxial light

    OpenAIRE

    Klaers, J.; Schmitt, J.; Damm, T.; Vewinger, F.; Weitz, M.

    2011-01-01

    Photons, due to the virtually vanishing photon-photon interaction, constitute to very good approximation an ideal Bose gas, but owing to the vanishing chemical potential a (free) photon gas does not show Bose-Einstein condensation. However, this is not necessarily true for a lower-dimensional photon gas. By means of a fluorescence induced thermalization process in an optical microcavity one can achieve a thermal photon gas with freely adjustable chemical potential. Experimentally, we have obs...

  7. Effects of non-condensable gas on the condensation of steam

    International Nuclear Information System (INIS)

    Jackson, J.D.; An, P.; Reinert, A.; Ahmadinejad, M.

    2000-01-01

    The experimental work reported here was undertaken with the aim of extending the database currently available on the condensation of steam in the presence of non-condensable gases and thereby improving the empirical input to thermal-hydraulic codes which might be used for design and safety assessment of advanced water-cooled nuclear reactors. Heat was removed from flowing mixtures of steam and air in a test section by means of a water-cooled condensing plate. The test facility constructed for the study incorporates a degassing unit which supplies water to a boiler. This delivers steam steadily to a mixing chamber where it joins with a flow of preheated air. The mixture of steam and air is supplied to the bottom of a cylindrical test section in which it flows upwards over a double sided condensing plate which can be vertical, inclined or horizontal, The rate at which heat is removed by cooling water flowing through internal passages in the plate can de determined calorimetrically knowing the flow rate of the water and its temperature rise. After commissioning experiments had shown that reliable measurements of condensation heat transfer rate could be made using the test facility, a programme of development work followed in the course of which three different designs of condensing plate were evaluated in turn. The version eventually used in the main programme of experiments which followed was made from copper. However, its surfaces were coated with a thin layer of nickel and then with one of chromium. It was found that such a surface consistently promoted dropwise condensation and showed no signs of deterioration after lengthy periods of use. The rate of heat removal from pure steam and from mixtures of steam and air in varying proportions was measured as a function of plate sub-cooling for a variety of plate orientations. (author)

  8. Landau damping in trapped Bose condensed gases

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, B; Zaremba, E [Department of Physics, Queen' s University, Kingston, ON K7L 3N6 (Canada)

    2003-07-01

    We study Landau damping in dilute Bose-Einstein condensed gases in both spherical and prolate ellipsoidal harmonic traps. We solve the Bogoliubov equations for the mode spectrum in both of these cases, and calculate the damping by summing over transitions between excited quasiparticle states. The results for the spherical case are compared to those obtained in the Hartree-Fock (HF) approximation, where the excitations take on a single-particle character, and excellent agreement between the two approaches is found. We have also taken the semiclassical limit of the HF approximation and obtain a novel expression for the Landau damping rate involving the time-dependent self-diffusion function of the thermal cloud. As a final approach, we study the decay of a condensate mode by making use of dynamical simulations in which both the condensate and thermal cloud are evolved explicitly as a function of time. A detailed comparison of all these methods over a wide range of sample sizes and trap geometries is presented.

  9. Condensate bright solitons under transverse confinement

    International Nuclear Information System (INIS)

    Salasnich, L.; Reatto, L.; Parola, A.

    2002-01-01

    We investigate the dynamics of Bose-Einstein condensate bright solitons made of alkali-metal atoms with negative scattering length and under harmonic confinement in the transverse direction. Contrary to the one-dimensional (1D) case, the 3D bright soliton exists only below a critical attractive interaction that depends on the extent of confinement. Such a behavior is also found in multisoliton condensates with box boundary conditions. We obtain numerical and analytical estimates of the critical strength beyond which the solitons do not exist. By using an effective 1D nonpolynomial nonlinear Schroedinger equation, which accurately takes into account the transverse dynamics of cigarlike condensates, we numerically simulate the dynamics of the 'soliton train' reported in a recent experiment [Nature (London) 417, 150 (2002)]. Then, analyzing the macroscopic quantum tunneling of the bright soliton on a Gaussian barrier, we find that its interference in the tunneling region is strongly suppressed with respect to nonsolitonic case; moreover, the tunneling through a barrier breaks the shape invariance of the matter wave. Finally, we show that the collapse of the soliton is induced by the scattering on the barrier or by the collision with another matter wave when the density reaches a critical value, for which we derive an accurate analytical formula

  10. Radiating shocks and condensations in flares

    International Nuclear Information System (INIS)

    Fisher, G.H.

    1985-01-01

    Rapid energy release (by either ''thick target'' (beam) or ''thermal'' models of heating) in solar flare loop models usually leads to ''chromospheric evaporation,'' the process of heating cool chromospheric material to coronal temperatures, and the resulting increase in hot soft x-ray emitting plasma. The evaporated plasma flows up into the coronal portion of the loop because of the increased pressure in the evaporated region. However, the pressure increase also leads to a number of interesting phenomena in the flare chromosphere, which will be the subject of this paper. The sudden pressure increase in the evaporated plasma initiates a downward moving ''chromospheric condensation,'' an overdense region which gradually decelerates as it accretes material and propagates into the gravitationally stratified chromosphere. Solutions to an equation of motion for this condensation shows that its motion decays after about one minute of propagation into the chromosphere. When the front of this downflowing region is supersonic relative to the atmosphere ahead of it, a radiating shock will form. If the downflow is rapid enough, the shock strength should be sufficient to excite uv radiation normally associated with the transition region, and furthermore, the radiating shock will be brighter than the transition region. These results lead to a number of observationally testable relationships between the optical and ultraviolet spectra from the condensation and radiating shock

  11. Capillary condensation of short-chain molecules.

    Science.gov (United States)

    Bryk, Paweł; Pizio, Orest; Sokolowski, Stefan

    2005-05-15

    A density-functional study of capillary condensation of fluids of short-chain molecules confined to slitlike pores is presented. The molecules are modeled as freely jointed tangent spherical segments with a hard core and with short-range attractive interaction between all the segments. We investigate how the critical parameters of capillary condensation of the fluid change when the pore width decreases and eventually becomes smaller than the nominal linear dimension of the single-chain molecule. We find that the dependence of critical parameters for a fluid of dimers and of tetramers on pore width is similar to that of the monomer fluid. On the other hand, for a fluid of chains consisting of a larger number of segments we observe an inversion effect. Namely, the critical temperature of capillary condensation decreases with increasing pore width for a certain interval of values of the pore width. This anomalous behavior is also influenced by the interaction between molecules and pore walls. We attribute this behavior to the effect of conformational changes of molecules upon confinement.

  12. Bose-Einstein condensation of paraxial light

    Science.gov (United States)

    Klaers, J.; Schmitt, J.; Damm, T.; Vewinger, F.; Weitz, M.

    2011-10-01

    Photons, due to the virtually vanishing photon-photon interaction, constitute to very good approximation an ideal Bose gas, but owing to the vanishing chemical potential a (free) photon gas does not show Bose-Einstein condensation. However, this is not necessarily true for a lower-dimensional photon gas. By means of a fluorescence induced thermalization process in an optical microcavity one can achieve a thermal photon gas with freely adjustable chemical potential. Experimentally, we have observed thermalization and subsequently Bose-Einstein condensation of the photon gas at room temperature. In this paper, we give a detailed description of the experiment, which is based on a dye-filled optical microcavity, acting as a white-wall box for photons. Thermalization is achieved in a photon number-conserving way by photon scattering off the dye molecules, and the cavity mirrors both provide an effective photon mass and a confining potential-key prerequisites for the Bose-Einstein condensation of photons. The experimental results are in good agreement with both a statistical and a simple rate equation model, describing the properties of the thermalized photon gas.

  13. Study of condensate removal from wells

    Energy Technology Data Exchange (ETDEWEB)

    Gusein-Zade, Z I

    1967-01-01

    A pressure profile of well No. 218 in the Karadag condensate field showed that pressure did not vary linearly with depth. Calculations indicated that at depths of 3,000-3,640 m, produced fluid had a density of 0.29g/ cmU3D, whereas pure condensate gas should have a density of 0.11g/cmU3D. Apparently liquid was accumulating in the well. Other data showed that gas velocity in the well at various depths varied from 6 to 11 m/sec. It was also found that this same range of gas velocities was sufficient to prevent liquid accumulation in other wells. In an effort to solve this problem, the upward flow of gas-water and of gas-condensate mixtures in tubes was studied. Each had a different flow regime. Gas-condsensate formed foam, whereas the gas-water mixture did not. This resolved the problem, since foam is known to aid the removal of liquid by gas. Additional research showed that water was present in, and promoted accumulation of, liquid in well No. 218.

  14. Condensation with two constraints and disorder

    Science.gov (United States)

    Barré, J.; Mangeolle, L.

    2018-04-01

    We consider a set of positive random variables obeying two additive constraints, a linear and a quadratic one; these constraints mimic the conservation laws of a dynamical system. In the simplest setting, without disorder, it is known that such a system may undergo a ‘condensation’ transition, whereby one random variable becomes much larger than the others; this transition has been related to the spontaneous appearance of non linear localized excitations in certain nonlinear chains, called breathers. Motivated by the study of breathers in a disordered discrete nonlinear Schrödinger equation, we study different instances of this problem in presence of a quenched disorder. Unless the disorder is too strong, the phase diagram looks like the one without disorder, with a transition separating a fluid phase, where all variables have the same order of magnitude, and a condensed phase, where one variable is much larger than the others. We then show that the condensed phase exhibits various degrees of ‘intermediate symmetry breaking’: the site hosting the condensate is chosen neither uniformly at random, nor is it fixed by the disorder realization. Throughout the article, our heuristic arguments are complemented with direct Monte Carlo simulations.

  15. Improvement of reliability of heater and condenser

    International Nuclear Information System (INIS)

    Yamagishi, Hiroki

    1988-01-01

    Recently, the diversification of the operation modes of power plants has advanced as well as daily start and stop and weekly start and stop operations, as the result, the needs for the reliability improvement of various heat exchangers around steam turbines heighten. In newly constructed plants, the design to meet this demand is carried out, but also in existing platns, the application of the latest technology is investigated. As for the reliability of condensers, aluminum brass cooling tubes have been used by doing the optimal maintenance and taking the measures against deposit attack. In the case of requiring high reliability, the examples of adopting titanium cooling tubes increased. The technology of titanium tube condensers, completely assembled condensers, the replacement of existing brass tubes with titanium tubes and so on are discussed. In the case of feed heaters, the deterioration phenomena due to the lapse of long years, such as the attack of steel tube inlet, the drain attack on the external surfaces of steel tubes, the ammonia attack of aluminum brass tubes and the adhesion of scale to heaters, are explained, and the countermeasures are shown. (Kako, I.)

  16. The moon as a high temperature condensate.

    Science.gov (United States)

    Anderson, D. L.

    1973-01-01

    The accretion during condensation mechanism, if it occurs during the early over-luminous stage of the sun, can explain the differences in composition of the terrestrial planets and the moon. An important factor is the variation of pressure and temperature with distance from the sun, and in the case of the moon and captured satellites of other planets, with distance from the median plane. Current estimates of the temperature and pressure in the solar nebula suggest that condensation will not be complete in the vicinity of the terrestrial planets, and that depending on location, iron, magnesium silicates and the volatiles will be at least partially held in the gaseous phase and subject to separation from the dust by solar wind and magnetic effects associated with the transfer of angular momentum just before the sun joins the Main Sequence. Many of the properties of the moon, including the 'enrichment' in Ca, Al, Ti, U, Th, Ba, Sr and the REE and the 'depletion' in Fe, Rb, K, Na and other volatiles can be understood if the moon represents a high temperature condensate from the solar nebula.

  17. Geysers advanced direct contact condenser research

    Energy Technology Data Exchange (ETDEWEB)

    Henderson, J.; Bahning, T.; Bharathan, D.

    1997-12-31

    The first geothermal application of the Advanced Direct Contact Condenser (ADCC) technology developed by the National Renewable Energy Laboratory (NREL) is now operational and is being tested at The Geysers Power Plant Unit 11. This major research effort is being supported through the combined efforts of NREL, The Department of Energy (DOE), and Pacific Gas and Electric (PG&E). NREL and PG&E have entered into a Cooperative Research And Development Agreement (CRADA) for a project to improve the direct-contact condenser performance at The Geysers Power Plant. This project is the first geothermal adaptation of an advanced condenser design developed for the Ocean Thermal Energy Conversion (OTEC) systems. PG&E expects this technology to improve power plant performance and to help extend the life of the steam field by using steam more efficiently. In accordance with the CRADA, no money is transferred between the contracting parties. In this case the Department of Energy is funding NREL for their efforts in this project and PG&E is contributing funds in kind. Successful application of this technology at The Geysers will provide a basis for NREL to continue to develop this technology for other geothermal and fossil power plant systems.

  18. On inflation in the presence of a gaugino condensate

    International Nuclear Information System (INIS)

    Lebedev, Oleg; Papineau, Chloe

    2009-07-01

    We study the effect of inflation on gaugino condensation in supergravity. Unless the Hubble scale H is significantly below the gaugino condensation scale, the gaugino condensate is a dynamical variable which cannot be integrated out. For a sufficiently high H, the gaugino condensate evolves to zero which in turn leads to dilaton/moduli destabilization. In practice, this often occurs at the Hubble rate about an order of magnitude below the gaugino condensation scale. This effect is independent of the specifics of moduli stabilization and thus places model independent constraints on inflationary scenarios. It also applies more generally to any periods of fast expansion in the early Universe. (orig.)

  19. On inflation in the presence of a gaugino condensate

    International Nuclear Information System (INIS)

    Lebedev, Oleg; Papineau, Chloe; Postma, Marieke

    2010-01-01

    We study the effect of inflation on gaugino condensation in supergravity. Unless the Hubble scale H is significantly below the gaugino condensation scale, the gaugino condensate is a dynamical variable which cannot be integrated out. For a sufficiently high H, the gaugino condensate evolves to zero which in turn leads to dilaton/moduli destabilization. In practice, this often occurs at the Hubble rate about an order of magnitude below the gaugino condensation scale. This effect is independent of the specifics of moduli stabilization and thus places model-independent constraints on inflationary scenarios. It also applies more generally to any periods of fast expansion in the early Universe.

  20. On inflation in the presence of a gaugino condensate

    Energy Technology Data Exchange (ETDEWEB)

    Lebedev, Oleg; Papineau, Chloe [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany). Theory Group; Postma, Marieke [NIKHEF, Amsterdam (Netherlands)

    2009-07-15

    We study the effect of inflation on gaugino condensation in supergravity. Unless the Hubble scale H is significantly below the gaugino condensation scale, the gaugino condensate is a dynamical variable which cannot be integrated out. For a sufficiently high H, the gaugino condensate evolves to zero which in turn leads to dilaton/moduli destabilization. In practice, this often occurs at the Hubble rate about an order of magnitude below the gaugino condensation scale. This effect is independent of the specifics of moduli stabilization and thus places model independent constraints on inflationary scenarios. It also applies more generally to any periods of fast expansion in the early Universe. (orig.)

  1. On inflation in the presence of a gaugino condensate

    Energy Technology Data Exchange (ETDEWEB)

    Lebedev, Oleg [DESY Theory Group, Notkestrasse 85, D-22607 Hamburg (Germany); Papineau, Chloe, E-mail: chloe.papineau@desy.d [DESY Theory Group, Notkestrasse 85, D-22607 Hamburg (Germany); Postma, Marieke [NIKHEF, Kruislaan 409, 1098 Amsterdam (Netherlands)

    2010-02-08

    We study the effect of inflation on gaugino condensation in supergravity. Unless the Hubble scale H is significantly below the gaugino condensation scale, the gaugino condensate is a dynamical variable which cannot be integrated out. For a sufficiently high H, the gaugino condensate evolves to zero which in turn leads to dilaton/moduli destabilization. In practice, this often occurs at the Hubble rate about an order of magnitude below the gaugino condensation scale. This effect is independent of the specifics of moduli stabilization and thus places model-independent constraints on inflationary scenarios. It also applies more generally to any periods of fast expansion in the early Universe.

  2. Condensate fluctuations of interacting Bose gases within a microcanonical ensemble.

    Science.gov (United States)

    Wang, Jianhui; He, Jizhou; Ma, Yongli

    2011-05-01

    Based on counting statistics and Bogoliubov theory, we present a recurrence relation for the microcanonical partition function for a weakly interacting Bose gas with a finite number of particles in a cubic box. According to this microcanonical partition function, we calculate numerically the distribution function, condensate fraction, and condensate fluctuations for a finite and isolated Bose-Einstein condensate. For ideal and weakly interacting Bose gases, we compare the condensate fluctuations with those in the canonical ensemble. The present approach yields an accurate account of the condensate fluctuations for temperatures close to the critical region. We emphasize that the interactions between excited atoms turn out to be important for moderate temperatures.

  3. Steam blowdown experiments with the condensation pool test rig

    International Nuclear Information System (INIS)

    Purhonen, H.; Puustinen, M.; Laine, J.; Raesaenen, A.; Kyrki-Rajamaeki, R.; Vihavainen, J.

    2005-01-01

    During a possible loss-of-coolant accident (Local) a large amount of non-condensable (nitrogen) and condensable (steam) gas is blown from the upper drywell of the containment to the condensation pool through the blowdown pipes at the boiling water reactors (BWRs). The wet well pool serves as the major heat sink for condensation of steam. The blowdown causes both dynamic and structural loads to the condensation pool. There might also be a risk that the gas discharging to the pool could push its way to the emergency core cooling systems (ECCS) and undermine their performance. (author)

  4. Competition between Bose-Einstein Condensation and Spin Dynamics.

    Science.gov (United States)

    Naylor, B; Brewczyk, M; Gajda, M; Gorceix, O; Maréchal, E; Vernac, L; Laburthe-Tolra, B

    2016-10-28

    We study the impact of spin-exchange collisions on the dynamics of Bose-Einstein condensation by rapidly cooling a chromium multicomponent Bose gas. Despite relatively strong spin-dependent interactions, the critical temperature for Bose-Einstein condensation is reached before the spin degrees of freedom fully thermalize. The increase in density due to Bose-Einstein condensation then triggers spin dynamics, hampering the formation of condensates in spin-excited states. Small metastable spinor condensates are, nevertheless, produced, and they manifest in strong spin fluctuations.

  5. 40 CFR 405.110 - Applicability; description of the condensed whey subcategory.

    Science.gov (United States)

    2010-07-01

    ... condensed whey subcategory. 405.110 Section 405.110 Protection of Environment ENVIRONMENTAL PROTECTION... Condensed Whey Subcategory § 405.110 Applicability; description of the condensed whey subcategory. The... whey and condensed acid whey. ...

  6. Titanium condenser tubes. Problems and their solution for wider application to large surface condensers. [PWR

    Energy Technology Data Exchange (ETDEWEB)

    Sato, S; Sugiyama, S; Nagata, K; Nanba, K; Shimono, M [Sumitomo Light Metal Industries Ltd., Tokyo (Japan)

    1977-06-01

    The corrosion resistance of titanium in sea water is extremely excellent, but titanium tubes are expensive, and the copper alloy tubes resistant in polluted sea water were developed, therefore they were not used practically. In 1970, ammonia attack was found on the copper alloy tubes in the air-cooled portion of condensers, and titanium tubes have been used as the countermeasure. As the result of the use, the galvanic attack on copper alloy tube plates with titanium tubes as cathode and the hydrogen absorption at titanium tube ends owing to excess electrolytic protection was observed, but the corrosion resistance of titanium tubes was perfect. These problems can be controlled by the application of proper electrolytic protection. The condensers with all titanium tubes adopted recently in USA are intended to realize perfectly no-leak condensers as the countermeasure to the corrosion in steam generators of PWR plants. Regarding large condensers of nowadays, three problems are pointed out, namely the vibration of condenser tubes, the method of joining tubes and tube plates, and the tubes of no coolant leak. These three problems in case of titanium tubes were studied, and the problem of the fouling of tubes was also examined. The intervals of supporting plates for titanium tubes should be narrowed. The joining of titanium tubes and titanium tube plates by welding is feasible and promising. The cleaning with sponge balls is effective to control fouling.

  7. A Local Condensation Analysis Representing Two-phase Annular Flow in Condenser/radiator Capillary Tubes

    Science.gov (United States)

    Karimi, Amir

    1991-01-01

    NASA's effort for the thermal environmental control of the Space Station Freedom is directed towards the design, analysis, and development of an Active Thermal Control System (ATCS). A two phase, flow through condenser/radiator concept was baselined, as a part of the ATCS, for the radiation of space station thermal load into space. The proposed condenser rejects heat through direct condensation of ATCS working fluid (ammonia) in the small diameter radiator tubes. Analysis of the condensation process and design of condenser tubes are based on the available two phase flow models for the prediction of flow regimes, heat transfer, and pressure drops. The prediction formulas use the existing empirical relationships of friction factor at gas-liquid interface. An attempt is made to study the stability of interfacial waves in two phase annular flow. The formulation is presented of a stability problem in cylindrical coordinates. The contribution of fluid viscosity, surface tension, and transverse radius of curvature to the interfacial surface is included. A solution is obtained for Kelvin-Helmholtz instability problem which can be used to determine the critical and most dangerous wavelengths for interfacial waves.

  8. Assessment of TRACE Condensation Model Against Reflux Condensation Tests with Noncondensable Gases

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kyung Won; Cheong, Ae Ju; Shin, Andong; Suh, Nam Duk [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2015-05-15

    The TRACE is the latest in a series of advanced, best-estimated reactor systems code developed by U.S. Nuclear Regulatory Commission for analyzing transient and steady-state neutronic-thermal-hydraulic behavior in light water reactors. This special model is expected to replace the default model in a future code release after sufficient testing has been completed. This study assesses the special condensation model of TRACE 5.0-patch4 against the counter-current flow configuration. For this purpose, the predicted results of special model are compared to the experimental and to those of default model. The KAST reflux condensation test with NC gases are used in this assessment. We assessed the special model for film condensation of TRACE 5.0-patch4 against the data of the reflux condensation test in the presence of NC gases. The special condensation model of TRACE provides a reasonable estimate of HTC with good agreement at the low inlet steam flow rate.

  9. Assessment of TRACE Condensation Model Against Reflux Condensation Tests with Noncondensable Gases

    International Nuclear Information System (INIS)

    Lee, Kyung Won; Cheong, Ae Ju; Shin, Andong; Suh, Nam Duk

    2015-01-01

    The TRACE is the latest in a series of advanced, best-estimated reactor systems code developed by U.S. Nuclear Regulatory Commission for analyzing transient and steady-state neutronic-thermal-hydraulic behavior in light water reactors. This special model is expected to replace the default model in a future code release after sufficient testing has been completed. This study assesses the special condensation model of TRACE 5.0-patch4 against the counter-current flow configuration. For this purpose, the predicted results of special model are compared to the experimental and to those of default model. The KAST reflux condensation test with NC gases are used in this assessment. We assessed the special model for film condensation of TRACE 5.0-patch4 against the data of the reflux condensation test in the presence of NC gases. The special condensation model of TRACE provides a reasonable estimate of HTC with good agreement at the low inlet steam flow rate

  10. Organic condensation: a vital link connecting aerosol formation to cloud condensation nuclei (CCN) concentrations

    Science.gov (United States)

    Riipinen, I.; Pierce, J. R.; Yli-Juuti, T.; Nieminen, T.; Häkkinen, S.; Ehn, M.; Junninen, H.; Lehtipalo, K.; Petäjä, T.; Slowik, J.; Chang, R.; Shantz, N. C.; Abbatt, J.; Leaitch, W. R.; Kerminen, V.-M.; Worsnop, D. R.; Pandis, S. N.; Donahue, N. M.; Kulmala, M.

    2011-04-01

    Atmospheric aerosol particles influence global climate as well as impair air quality through their effects on atmospheric visibility and human health. Ultrafine (<100 nm) particles often dominate aerosol numbers, and nucleation of atmospheric vapors is an important source of these particles. To have climatic relevance, however, the freshly nucleated particles need to grow in size. We combine observations from two continental sites (Egbert, Canada and Hyytiälä, Finland) to show that condensation of organic vapors is a crucial factor governing the lifetimes and climatic importance of the smallest atmospheric particles. We model the observed ultrafine aerosol growth with a simplified scheme approximating the condensing species as a mixture of effectively non-volatile and semi-volatile species, demonstrate that state-of-the-art organic gas-particle partitioning models fail to reproduce the observations, and propose a modeling approach that is consistent with the measurements. We find that roughly half of the mass of the condensing mass needs to be distributed proportional to the aerosol surface area (thus implying that the condensation is governed by gas-phase concentration rather than the equilibrium vapour pressure) to explain the observed aerosol growth. We demonstrate the large sensitivity of predicted number concentrations of cloud condensation nuclei (CCN) to these interactions between organic vapors and the smallest atmospheric nanoparticles - highlighting the need for representing this process in global climate models.

  11. Fluegas condensation of domestic fuels. Kotimaisten polttoaineiden savukaasulauhdutus

    Energy Technology Data Exchange (ETDEWEB)

    Kankkunen, A; Fagerholm, N E

    1988-01-01

    The suitability of domestic fuel for condensation heat recovery was studied. With the developed computer program, enthalpies of flue gas as function of temperature were computed and also the theoretical advandages aquired by condensation were compared with different fuels. The maximal advantages of condensation were 39 % with wooden chips and 31 % with peat. The domestic fuels were found to be useful for condensation heat recovery because of the high water content and the high dewpoint of flu egas. Condensation was found to have a purifying effect on flue gases. It was found experimentaly that 30 % the sulfur of the peat dissolved to the condensed liquid. The composition of condensed liquid of peat- and wooden chip flue gases was studied to find out the corrosion and enviromental effects. The risk of corrosion to metallic heat exhanger was concluded from the compositio of peat condensat. Chip condensate was found to be almost neutral. Normally the condensate liquids were fit for sewering without aftertreatment. Heat transfer coefficient from flue gases to the wall of the condenser was measured to be 150-170 W/Km{sup 2}. Heat transfer coefficients were three times higher compared to condensing heat transfer.

  12. A macrothermodynamic approach to the limit of reversible capillary condensation.

    Science.gov (United States)

    Trens, Philippe; Tanchoux, Nathalie; Galarneau, Anne; Brunel, Daniel; Fubini, Bice; Garrone, Edoardo; Fajula, François; Di Renzo, Francesco

    2005-08-30

    The threshold of reversible capillary condensation is a well-defined thermodynamic property, as evidenced by corresponding states treatment of literature and experimental data on the lowest closure point of the hysteresis loop in capillary condensation-evaporation cycles for several adsorbates. The nonhysteretical filling of small mesopores presents the properties of a first-order phase transition, confirming that the limit of condensation reversibility does not coincide with the pore critical point. The enthalpy of reversible capillary condensation can be calculated by a Clausius-Clapeyron approach and is consistently larger than the condensation heat in unconfined conditions. Calorimetric data on the capillary condensation of tert-butyl alcohol in MCM-41 silica confirm a 20% increase of condensation heat in small mesopores. This enthalpic advantage makes easier the overcoming of the adhesion forces by the capillary forces and justifies the disappearing of the hysteresis loop.

  13. Estudo do comportamento das resinas de estereolitografia Huntsman 5260 e Somos 7110 na fabricação rápida de moldes para injeção de PP, ABS, PA 6.6 e PET

    OpenAIRE

    Gonçalves, Mathias Westphal

    2005-01-01

    Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Ciência e Engenharia de Materiais Estereolitogrfia é um processo de fabricação rápida (FR) no qual a construção do objeto se da através da cura seletiva de uma resina fotossensível, camada após camada. Devido à boa precisão geométrica das peças fabricadas, este processo tem sido utilizado também para a fabricação de ferramentas como moldes para injeção de termoplásticos onde po...

  14. Tensile bond srength between composite resin using different adhesive systems Avaliação da resistência à ruptura por tração entre resina composta e diversos adesivos dentinários

    Directory of Open Access Journals (Sweden)

    Patrícia Dias

    2002-11-01

    Full Text Available The aim of this study was evaluate the tensile bond strength (TBS among nine adhesive systems and one composite resin. The groups were made as follows: Single Bond/3M (G1, Etch & Prime 3.0 /Degussa (G2, Bond 1/Jeneric/Pentron (G3, Prime & Bond 2.1/Dentsply (G4, OptiBond FL/Kerr (G5, Stae/SDI (G6, Snap Bond/ Copalite-Cooley & Cooley (G7, Prime & Bond NT/Dentsply (G8, Scotchbond Multi Purpose Plus/3M (G9. The control group (G10 was made only with the composite resin (Z100/3M. One hundred specimens were made, 10 for each group. There were significant differences on TBS among groups. G3 showed the hightest TBS in comparison to other tested groups. G10 presented higher TBS than all groups. O objetivo desta pesquisa foi investigar in vitro a resistência de união entre uma resina composta e nove sistemas adesivos dentinários. Os adesivos estudados foram assim agrupados: Single Bond/3M (G1, Etch & Prime 3.0/ Degussa (G2, Bond 1/Jeneric/Pentron (G3, Prime & Bond 2.1/Dentsply (G4, OptiBond FL/Kerr (G5, Stae/SDI (G6, Snap Bond/Copalite (G7, Prime & Bond NT/Dentsply (G 8, Scotchbond Multi Purpose Plus/3M (G9. O Grupo controle (G10. foi confeccionado somente com a resina composta (Z100/3M. Foram confeccionados 100 espécimes, 10 para cada grupo. Houve diferenças estatísticas significantes entre os grupos. O grupo 3 foi o que mostrou a mais alta resistência em comparação aos nove testados. O grupo controle (G10 apresentou a mais alta resistência entre todos os Grupos.  

  15. Propriedades mecânicas de materiais compósitos à base de cimento Portland e resina epoxi Mechanical properties of composite materials based on portland cement and epoxy resin

    Directory of Open Access Journals (Sweden)

    T. H. Panzera

    2010-03-01

    Full Text Available O estudo de materiais de alto desempenho e multifuncionais, como os compósitos poliméricos cimentícios, tem sido o foco de inúmeras pesquisas na indústria da construção civil. Este trabalho investiga o efeito da combinação de uma fase polimérica termorrígida, uma resina epóxi, com cimento Portland branco estrutural, seguido da avaliação da resistência à compressão e módulo de elasticidade. Este compósito, quando comparado individualmente com as suas matérias-prima originais, promove um aumento da resistência mecânica à compressão, redução da massa específica e, também uma mudança significativa do comportamento mecânico. As mudanças nas propriedades mecânicas estão associadas à hidratação da fase cimentícia na presença da resina, fato comprovado através da análise espectroscópica na região do infravermelho.The study of multi-functional materials of high performance, as the polymeric-cementitious composites, has been the focus of several researches in the industry of the civil engineering. This work investigates the effect of the combination of a thermorigid epoxy phase and the white Portland cement, followed by the evaluation of its compressive strength and modulus of elasticity. This composite, when the phases are individually compared, provides an increase of the compressive strength, a reduction of the density, and a significant change of the mechanical behaviour. The changes in mechanical behaviour are associated with the hydration of cement in the presence of resin, which was evident after infrared spectroscopy analysis.

  16. Assessment of RELAP5/MOD3.3 condensation models for the tube bundle condensation in the PCCS of ESBWR

    International Nuclear Information System (INIS)

    Zhou, W.; Wolf, B.; Revankar, S.T.

    2011-01-01

    The passive containment condenser system (PCCS) in an ESBWR reactor consists of vertical tube bundle submerged in a large pool of water. The condensation model for the PCCS in a thermalhydraulics code RELAP5/MOD3.3 consists of the default Nusselt model and an alternate condensation model from UCB condensation correlation. An assessment of the PCCS condensation model in RELAP5/MOD3.3 was carried out using experiments conducted on a single tube and tube bundle PCCS tests at Purdue University. The experimental conditions were simulated with the default and the alternate condensation models in the REALP5/MOD3.3 beta version of the code. The default model and the UCB model (alternate model) give quite different results on condensation heat transfer for the PCCS. The default model predicts complete condensation well whereas the UCB model predicts the through flow condensation well. Based on this study it was found that none of the models in REALP5 can predict complete condensation as well as the through flow condensation well. (author)

  17. Assessment of RELAP5/MOD3.3 condensation models for the tube bundle condensation in the PCCS of ESBWR

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, W., E-mail: wenzzhou@cityu.edu.hk [Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Hong Kong (China); Wolf, B. [Purdue University, West Lafayette, IN 47907 (United States); Revankar, S. [Purdue University, West Lafayette, IN 47907 (United States); POSTECH, Pohang (Korea, Republic of)

    2013-11-15

    The passive containment condenser system (PCCS) in an ESBWR reactor consists of vertical tube bundle submerged in a large pool of water. The condensation model for the PCCS in a thermalhydraulics code RELAP5/MOD3.3 consists of the default Nusselt model and an alternate condensation model from UCB condensation correlation. An assessment of the PCCS condensation model in RELAP5/MOD3.3 was carried out using experiments conducted on a single tube and tube bundle PCCS tests at Purdue University. The experimental conditions were simulated with the default and the alternate condensation models in the REALP5/MOD3.3 beta version of the code. The default model and the UCB model (alternate model) give quite different results on condensation heat transfer for the PCCS. The default model predicts complete condensation well whereas the UCB model predicts the through flow condensation well. Based on this study it was found that none of the models in REALP5 can predict complete condensation as well as the through flow condensation well.

  18. QCD under extreme conditions. Inhomogeneous condensation

    Energy Technology Data Exchange (ETDEWEB)

    Heinz, Achim

    2014-10-15

    Almost 40 years after the first publication on the phase diagram of quantum chromodynamics (QCD) big progress has been made but many questions are still open. This work covers several aspects of low-energy QCD and introduces advanced methods to calculate selected parts of the QCD phase diagram. Spontaneous chiral symmetry breaking as well as its restoration is a major aspect of QCD. Two effective models, the Nambu-Jona-Lasinio (NJL) model and the linear σ-model, are widely used to describe the QCD chiral phase transition. We study the large-N{sub c} behavior of the critical temperature T{sub c} for chiral symmetry restoration in the framework of both models. While in the NJL model T{sub c} is independent of N{sub c} (and in agreement with the expected QCD scaling), the scaling behavior in the linear σ-model reads T{sub c} ∝ N{sup 1/2}{sub c}. However, this mismatch can be corrected: phenomenologically motivated temperature-dependent parameters or the extension with the Polyakov-loop renders the scaling in the linear σ-model compatible with the QCD scaling. The requirement that the chiral condensate which is the order parameter of the chiral symmetry is constant in space is too restrictive. Recent studies on inhomogeneous chiral condensation in cold, dense quark matter suggest a rich crystalline structure. These studies feature models with quark degrees of freedom. In this thesis we investigate the formation of the chiral density wave (CDW) in the framework of the so-called extended linear sigma model (eLSM) at high densities and zero temperature. The eLSM is a modern development of the linear σ-model which contains scalar, pseudoscalar, vector, as well as axial-vector mesons, and in addition, a light tetraquark state. The nucleon and its chiral partner are introduced as parity doublets in the mirror assignment. The model describes successfully the vacuum phenomenology and nuclear matter ground-state properties. As a result we find that an inhomogeneous phase

  19. Condensation energy density in Bi-2212 superconductors

    International Nuclear Information System (INIS)

    Matsushita, Teruo; Kiuchi, Masaru; Haraguchi, Teruhisa; Imada, Takeki; Okamura, Kazunori; Okayasu, Satoru; Uchida, Satoshi; Shimoyama, Jun-ichi; Kishio, Kohji

    2006-01-01

    The relationship between the condensation energy density and the anisotropy parameter, γ a , has been derived for Bi-2212 superconductors in various anisotropic states by analysing the critical current density due to columnar defects introduced by heavy ion irradiation. The critical current density depended on the size of the defects, determined by the kind and irradiation energy of the ions. A significantly large critical current density of 17.0 MA cm -2 was obtained at 5 K and 0.1 T even for the defect density of a matching field of 1 T in a specimen irradiated with iodine ions. The dependence of the critical current density on the size of the defects agreed well with the prediction from the summation theory of pinning forces, and the condensation energy density could be obtained consistently from specimens irradiated with different ions. The condensation energy density obtained increased with decreasing γ a over the entire range of measurement temperature, and reached about 60% of the value for the most three-dimensional Y-123 observed by Civale et al at 5 K. This gives the reason for the very strong pinning in Bi-2212 superconductors at low temperatures. The thermodynamic critical field obtained decreased linearly with increasing temperature and extrapolated to zero at a certain characteristic temperature, T * , lower than the critical temperature, T c . T * , which seems to be associated with the superconductivity in the block layers, was highest for the optimally doped specimen. This shows that the superconductivity becomes more inhomogeneous as the doped state of a superconductor deviates from the optimum condition

  20. Diffusion in condensed matter methods, materials, models

    CERN Document Server

    Kärger, Jörg

    2005-01-01

    Diffusion as the process of particle transport due to stochastic movement is a phenomenon of crucial relevance for a large variety of processes and materials. This comprehensive, handbook- style survey of diffusion in condensed matter gives detailed insight into diffusion as the process of particle transport due to stochastic movement. Leading experts in the field describe in 23 chapters the different aspects of diffusion, covering microscopic and macroscopic experimental techniques and exemplary results for various classes of solids, liquids and interfaces as well as several theoretical concepts and models. Students and scientists in physics, chemistry, materials science, and biology will benefit from this detailed compilation.

  1. Bose-Einstein Condensation in Complex Networks

    International Nuclear Information System (INIS)

    Bianconi, Ginestra; Barabasi, Albert-Laszlo

    2001-01-01

    The evolution of many complex systems, including the World Wide Web, business, and citation networks, is encoded in the dynamic web describing the interactions between the system's constituents. Despite their irreversible and nonequilibrium nature these networks follow Bose statistics and can undergo Bose-Einstein condensation. Addressing the dynamical properties of these nonequilibrium systems within the framework of equilibrium quantum gases predicts that the 'first-mover-advantage,' 'fit-get-rich,' and 'winner-takes-all' phenomena observed in competitive systems are thermodynamically distinct phases of the underlying evolving networks

  2. HADRONIC SCATTERING IN THE COLOR GLASS CONDENSATE.

    Energy Technology Data Exchange (ETDEWEB)

    VENUGOPALAN, R.

    2005-05-15

    Multi-particle production in QCD is dominated by higher twist contributions. The operator product expansion is not very effective here because the number of relevant operators grow rapidly with increasing twist. The Color Glass Condensate (CGC) provides a framework in QCD to systematically discuss ''classical'' (multiple scattering) and ''quantum'' evolution (shadowing) effects in multi-particle production. The apparently insuperable problem of nucleus-nucleus scattering in QCD simplifies greatly in the CGC. A few examples are discussed with emphasis on open problems.

  3. Hidden Scale Invariance in Condensed Matter

    DEFF Research Database (Denmark)

    Dyre, J. C.

    2014-01-01

    . This means that the phase diagram becomes effectively one-dimensional with regard to several physical properties. Liquids and solids with isomorphs include most or all van der Waals bonded systems and metals, as well as weakly ionic or dipolar systems. On the other hand, systems with directional bonding...... (hydrogen bonds or covalent bonds) or strong Coulomb forces generally do not exhibit hidden scale invariance. The article reviews the theory behind this picture of condensed matter and the evidence for it coming from computer simulations and experiments...

  4. Dispersion Engineering of Bose-Einstein Condensates

    Science.gov (United States)

    Khamehchi, Mohammad Amin

    The subject of this dissertation is engineering the dispersion relation for dilute Bose-Einstein condensates (BECs). When a BEC is immersed into suitably tailored laser fields its dispersion can be strongly modified. Prominent examples for such laser fields include optical lattice geometries and Raman dressing fields. The ability to engineer the dispersion of a BEC allows for the investigation of a range of phenomena related to quantum hydrodynamics and condensed matter. In the first context, this dissertation studies the excitation spectrum of a spin-orbit coupled (SOC) BEC. The spin-orbit coupling is generated by " dressing" the atoms with two Raman laser fields. The excitation spectrum has a Roton-like feature that can be altered by tuning the Raman laser parameters. It is demonstrated that the Roton mode can be softened, but it does not reach the ground state energy for the experimental conditions we had. Furthermore, the expansion of SOC BECs in 1D is studied by relaxing the trap allowing the BEC to expand in the SOC direction. Contrary to the findings for optical lattices, it is observed that the condensate partially occupies quasimomentum states with negative effective mass, and therefore an abrupt deceleration is observed although the mean field force is along the direction of expansion. In condensed-matter systems, a periodic lattice structure often plays an important role. In this context, an alternative to the Raman dressing scheme can be realized by coupling the s- and p- bands of a static optical lattice via a weak moving lattice. The bands can be treated as pseudo-spin states. It is shown that similar to the dispersion relation of a Raman dressed SOC, the quasimomentum of the ground state is different from zero. Coherent coupling of the SOC dispersion minima can lead to the realization of the stripe phase even though it is not the thermodynamic ground state of the system. Along the lines of studying the hydrodynamics of BECs, three novel

  5. Exhaled Breath Condensate for Proteomic Biomarker Discovery

    Directory of Open Access Journals (Sweden)

    Sean W. Harshman

    2014-07-01

    Full Text Available Exhaled breath condensate (EBC has been established as a potential source of respiratory biomarkers. Compared to the numerous small molecules identified, the protein content of EBC has remained relatively unstudied due to the methodological and technical difficulties surrounding EBC analysis. In this review, we discuss the proteins identified in EBC, by mass spectrometry, focusing on the significance of those proteins identified. We will also review the limitations surrounding mass spectral EBC protein analysis emphasizing recommendations to enhance EBC protein identifications by mass spectrometry. Finally, we will provide insight into the future directions of the EBC proteomics field.

  6. Boiling, condensation, and gas-liquid flow

    International Nuclear Information System (INIS)

    Whalley, P.B.

    1987-01-01

    Heat transfer phenomena involving boiling and condensation are an important aspect of engineering in the power and process industries. This book, aimed at advanced first-degree and graduate students in mechanical and chemical engineering, deals with these phenomena in detail. The first part of the book describes gas-liquid two-phase flow, as a necessary preliminary to the later discussion of heat transfer and change of phase. A detailed section on calculation methods shows how theory can be put to practical use, and there are also descriptions of some of the equipment and plant used in the process and power industries

  7. Long range correlations in condensed matter

    International Nuclear Information System (INIS)

    Bochicchio, R.C.

    1990-01-01

    Off diagonal long range order (ODLRO) correlations are strongly related with the generalized Bose-Einstein condensation. Under certain boundary conditions, one implies the other. These phenomena are of great importance in the description of quantum situations with a macroscopic manifestation (superfluidity, superconductivity, etc.). Since ion pairs are not bosons, the definition of ODLRO is modified. The information contained with the 2-particle propagator (electron pairs) and the consequences that lead to pairs statistics are shown in this presentation. The analogy between long range correlations and fluids is also analyzed. (Author). 17 refs

  8. Potentially Prebiotic Syntheses of Condensed Phosphates

    Science.gov (United States)

    Keefe, Anthony D.; Miller, Stanley L.

    1996-01-01

    In view of the importance of a prebiotic source of high energy phosphates, we have investigated a number of potentially prebiotic processes to produce condensed phosphates from orthophosphate and cyclic trimetaphosphate from tripolyphosphate. The reagents investigated include polymerizing nitriles, acid anhydrides, lactones, hexamethylene tetramine and carbon suboxide. A number of these processes give substantial yields of pyrophosphate from orthophosphate and trimetaphosphate from tripolyphosphate. Although these reactions may have been applicable in local areas, they are not sufficiently robust to have been of importance in the prebiotic open ocean.

  9. STRANGE BARYONIC MATTER AND KAON CONDENSATION

    Czech Academy of Sciences Publication Activity Database

    Gazda, Daniel; Friedman, E.; Gal, A.; Mareš, Jiří

    2011-01-01

    Roč. 26, 3-4 (2011), s. 567-569 ISSN 0217-751X. [11th International Workshop on Meson Production, Properties and Interaction. Krakow, 10.06.2010-15.06.2010] R&D Projects: GA ČR GA202/09/1441 Institutional research plan: CEZ:AV0Z10480505 Keywords : (K)over-bar-nuclear bound states * strange baryonic matter * kaon condensation Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.053, year: 2011

  10. Disoriented chiral condensate: Theory and phenomenology

    International Nuclear Information System (INIS)

    Bjorken, J.D.

    1997-12-01

    These notes are an abbreviated version of lectures given at the 1997 Zakopane School. They contain two topics. The first is a description in elementary terms of the basic ideas underlying the speculative hypothesis that pieces of strong-interaction vacuum with a rotated chiral order parameter, disoriented chiral condensate or DCC, might be produced in high energy elementary particle collisions. The second topic is a discussion of the phenomenological techniques which may be applied to data in order to experimentally search for the existence of DCC

  11. Holographic techniques for condensed matter systems

    International Nuclear Information System (INIS)

    Herzog, Chistopher

    2009-01-01

    Full text. Gauge/gravity duality, a concept which emerged from string theory, holds promise for revealing the secrets of certain strongly interacting real world condensed matter systems. Historically, string theorists presented their subject as a promising framework for a quantum theory of gravity. More recently, the AdS/CFT correspondence and gauge/gravity dualities have emerged as powerful tools for using what we already know about gravity to investigate the properties of strongly interacting field theories. In this colloquium, I will survey recent developments where black holes are used to calculate the thermodynamic and transport properties of quantum critical systems, superconductors, superfluids, and fermions at unitarity. (author)

  12. A color magnetic vortex condensate in QCD

    International Nuclear Information System (INIS)

    Ambjoern, J.; Olesen, P.

    1980-03-01

    It is shown that there exists a very close analogy between a lattice of vorticies in a superconductor near the critical field and a condensate of color magnetic flux tubes due to the unstable mode in QCD. This analogy makes it possible to identify a dynamical Higgs field in QCD. It is shown that the color magnetic flux tubes are quantized in terms of the center group Z(2) in the SU(2) case. In the case of SU(N) it is possible to select a color direction of the field such that one has Z(N) quantization. (Auth.)

  13. Amplitude-Mode Dynamics of Polariton Condensates

    International Nuclear Information System (INIS)

    Brierley, R. T.; Littlewood, P. B.; Eastham, P. R.

    2011-01-01

    We study the stability of collective amplitude excitations in nonequilibrium polariton condensates. These excitations correspond to renormalized upper polaritons and to the collective amplitude modes of atomic gases and superconductors. They would be present following a quantum quench or could be created directly by resonant excitation. We show that uniform amplitude excitations are unstable to the production of excitations at finite wave vectors, leading to the formation of density-modulated phases. The physical processes causing the instabilities can be understood by analogy to optical parametric oscillators and the atomic Bose supernova.

  14. Decay of bubble of disoriented chiral condensate

    International Nuclear Information System (INIS)

    Gani, V.A.; Kudryavtsev, A.E.; Belova, T.I.

    1999-01-01

    The space-time structure for the process of decay of a bubble of hypothetical phase -disoriented chiral condensate (DCC) i discussed. The evolution of the initial classical field configuration corresponding to the bubble of DCC is studied, both numerically and analytically. The decay of this initial configuration depends crucially on self-interaction of the pionic fields. It is shown that in some cases this self-interaction leads to the formation of sort of breather solution, formed from pionic fields situated in the center of the initial bubble of DCC. This breather looks like a long-lived source of pionic fields [ru

  15. Hadronic scattering in the color glass condensate

    Energy Technology Data Exchange (ETDEWEB)

    Venugopalan, R. [Brookhaven National Lab., Physics Department, Upton, NY (United States)

    2005-07-01

    Multi-particle production in QCD is dominated by higher twist contributions. The operator product expansion is not very effective here because the number of relevant operators grow rapidly with increasing twist. The color glass condensate (CGC) provides a framework in QCD to systematically discuss 'classical' (multiple scattering) and 'quantum' evolution (shadowing) effects in multi-particle production. The apparently insuperable problem of nucleus-nucleus scattering in QCD simplifies greatly in the CGC. A few examples are discussed with emphasis on open problems. (author)

  16. Dissipative phenomena in condensed matter some applications

    CERN Document Server

    Dattagupta, Sushanta

    2004-01-01

    From the field of nonequilibrium statistical physics, this graduate- and research-level volume treats the modeling and characterization of dissipative phenomena. A variety of examples from diverse disciplines like condensed matter physics, materials science, metallurgy, chemical physics etc. are discussed. Dattagupta employs the broad framework of stochastic processes and master equation techniques to obtain models for a wide range of experimentally relevant phenomena such as classical and quantum Brownian motion, spin dynamics, kinetics of phase ordering, relaxation in glasses, dissipative tunneling. It provides a pedagogical exposition of current research material and will be useful to experimentalists, computational physicists and theorists.

  17. Construction of the blowdown and condensation loop

    Energy Technology Data Exchange (ETDEWEB)

    Park, Choon Kyung; Song, Chul Kyung; Cho, Seok; Chun, S. Y.; Chung, Moon Ki

    1997-12-01

    The blowdown and condensation loop (B and C loop) has been constructed to get experimental data for designing the safety depressurization system (SDS) and steam sparger which are considered to implement in the Korea Next Generation Reactor (KNGR). In this report, system description on the B and C loop is given in detail, which includes the drawings and technical specification of each component, instrumentation and control system, and the operational procedures and the results of the performance testing. (author). 7 refs., 11 tabs., 48 figs.

  18. Condensate treatment and oxygen control in power plants

    International Nuclear Information System (INIS)

    Sakai, Toshiaki; Iida, Kei; Ohashi, Shinichi.

    1997-01-01

    In thermal and nuclear power stations, the steam that operated turbines is cooled and condensed with condensers. The condensate is heated again with boilers, nuclear reactors or steam generators, but if corrosion products or impurities are contained in the condensate, corrosion and scale formation occur in boilers and others. The filtration facility and the desalting facility for condensate are installed to remove impurities, but water quality control is different in thermal, BWR and PWR plants, therefore, the treatment facilities corresponding to respective condensates have been adopted. In order to reduce the amount of clud generation, the treatment of injecting a small quantity of oxygen into condensate has been adopted. In thermal power plants, all volatile treatment is carried out, in which corrosion is prevented by the addition of ammonia and hydrazine to boiler feedwater. The condensate filters of various types and the NH 4 type condensate desalter for thermal power plants are described. In BWR power plants, steam is generated in nuclear reactors, therefore, the addition of chemicals into water is never carried out, and high purity neutral water is used. In PWR power plants, the addition of chemicals to water is done in the primary system, and AVT is adopted in the secondary system. Also the condensate treatment facilities are different for both reactors. (K.I.)

  19. Development of balanced downflow type surface condensers, (2)

    International Nuclear Information System (INIS)

    Tomida, Akira; Oshima, Yoshikuni; Okochi, Isao; Izumi, Kenkichi.

    1976-01-01

    As the size of the condensers for power generation plants grew large, the new balanced downflow type condenser was developed and completed on the basis of the experiment on steam flow according to the two-dimensional flow model, the analysis of the performance in a tube nest with a computer, and the studies on the effect of outside liquid film and the reheating deaeration of condensate. When the balanced downflow type condensers were adopted for actual plants, the construction, strength and production method were examined, and the reliability of the new condenser was confirmed by the thermal characteristic experiment with the model similar to the actual machine. The condenser comprises a condenser body, supporting plates, cooling tubes, tube plates, water chambers, and reinforcements, and the cooling tubes are arranged so as to exchange heat effectively. The arrangement of tubes is divided into three regions, namely radiation portion, densely arranged portion, and air cooling portion. In the balanced downflow type condensers, the dilution by utilizing condensate is provided against ammonia attack. The apparatuses for the thermal characteristic experiment and the experimental results, and the results of the performance test on the actual balanced downflow type condenser are reported. (Kako, I.)

  20. Systematic text condensation: a strategy for qualitative analysis.

    Science.gov (United States)

    Malterud, Kirsti

    2012-12-01

    To present background, principles, and procedures for a strategy for qualitative analysis called systematic text condensation and discuss this approach compared with related strategies. Giorgi's psychological phenomenological analysis is the point of departure and inspiration for systematic text condensation. The basic elements of Giorgi's method and the elaboration of these in systematic text condensation are presented, followed by a detailed description of procedures for analysis according to systematic text condensation. Finally, similarities and differences compared with other frequently applied methods for qualitative analysis are identified, as the foundation of a discussion of strengths and limitations of systematic text condensation. Systematic text condensation is a descriptive and explorative method for thematic cross-case analysis of different types of qualitative data, such as interview studies, observational studies, and analysis of written texts. The method represents a pragmatic approach, although inspired by phenomenological ideas, and various theoretical frameworks can be applied. The procedure consists of the following steps: 1) total impression - from chaos to themes; 2) identifying and sorting meaning units - from themes to codes; 3) condensation - from code to meaning; 4) synthesizing - from condensation to descriptions and concepts. Similarities and differences comparing systematic text condensation with other frequently applied qualitative methods regarding thematic analysis, theoretical methodological framework, analysis procedures, and taxonomy are discussed. Systematic text condensation is a strategy for analysis developed from traditions shared by most of the methods for analysis of qualitative data. The method offers the novice researcher a process of intersubjectivity, reflexivity, and feasibility, while maintaining a responsible level of methodological rigour.

  1. Study on corrosion of thermal power plant condenser tubes

    Energy Technology Data Exchange (ETDEWEB)

    Mohammadi, Abdolreza Rashidi; Zhaam, Ali Akbar [Niroo Research Institute, end of Poonak Bakhtari blvd., Shahrak Ghods, Tehran (Iran)

    2004-07-01

    The aim of this investigation is to study kinds of corrosion mechanisms in thermal power plant condenser tubes. Condenser is a shell and tube heat exchanger in which cooling water flows through its tubes. While the steam from low pressure turbine passes within condenser tubes, it is condensed by cooling water. The exhausted steam from low pressure turbine is condensed on external surface of condenser tubes and heat is transferred to cooling water which flow into tubes. Tubes composition is usually copper-based alloys, stainless steel or titanium. Annual damages due to corrosion cause much cost for replacement and repairing metallic equipment and installations in electric power industry. Because of existence of different contaminants in water and steam cycle, condenser tubes surfaces are exposed to corrosion. Contaminants like oxygen, carbon dioxide, chloride ion and ammonia in water and steam cycle originate several damages such as pitting and crevice corrosion, erosion, galvanic attack, SCC, condensed corrosion, de-alloying in thermal power plant condenser. The paper first states how corrosion damage takes place in condensers and then introduces types of usual alloys used in condensers and also their corrosion behavior. In continuation, a brief explanation is presented about kinds of condenser failures due to corrosion. Then, causes and locations of different mechanisms of corrosion events on condenser tubes and effects of different parameters such as composition, temperature, chloride and sulfide ion concentration, pH, water velocity and biological precipitation are examined and finally protection methods are indicated. Also some photos of tubes specimens related to power plants are studied and described in each case of mentioned mechanisms. (authors)

  2. Utilização de uma resina preparada pelo método da solução líquida de citratos como ligante durante a preparação de filtros cerâmicos à base de alumina

    OpenAIRE

    Gouvêa,D.; Savaglia Neto,W. A.; Capocchi,J. D. T.

    1999-01-01

    Este trabalho propõe a preparação de filtros cerâmicos macroporosos pela técnica da impregnação de espumas de poliuretano e utilização de uma resina preparada pelo método Pechini contendo íons alumínio e manganês como ligante. Nas temperaturas inferiores à de combustão da resina a parte orgânica age com ligante. Após a decomposição térmica, o produto da combustão, ou seja, alumina contendo íons Mn, passa a ser um ligante inorgânico mas apresentando composição química semelhante à do filtro. O...

  3. The effect of non-condensable gas on direct contact condensation of steam/air mixture

    International Nuclear Information System (INIS)

    Lee, H. C.; Park, S. K.; Kim, M. H.

    1998-01-01

    To investigate the effects of noncondensable gas on the direct contact film condensation of vapor mixture, a series of experiments has been carried out. The rectangular duct inclined 87.deg. to the horizontal plane was used for this experiment. The average heat transfer coefficient of the steam-air mixture was obtained at the atmospheric pressure with four main parameters, air-mass fraction, vapor velocity, film Reynolds number,and the degree of water film subcooling having an influence on the condensation heat transfer coefficient. With the analysis on 88 cases of experiments, a correlation of the average Nusselt number for direct contact film condensation of steam-air mixture at a vertical wall proposed as functions of film Reynolds number, mixture Reynolds number, air mass fraction, and Jacob number. The average heat transfer coefficient for steam-air mixture condensation decreased significantly while air mass fraction increases with the same inlet mixture velocity and inlet film temperature. The average heat transfer coefficients also decreased with the degree of film subcooling increasing and were scarcely affected by film Reynolds number below the mixture Reynolds number about 30,000

  4. On the prediction of condenser plate temperatures in a cross-flow condenser

    NARCIS (Netherlands)

    Ganzevles, F.L.A.; Geld, van der C.W.M.

    2002-01-01

    A prediction method is presented for the gas-sided plate temperatures at the inlet and at the outlet of a compact, cross-flow condenser. The method employs measured (or predicted) heat flow rates and temperatures of both coolant and gas, at inlet and outlet. The method is validated using infrared

  5. Heat transfer from a high temperature condensable mixture. II. Sedimentation of fog condensate

    International Nuclear Information System (INIS)

    Condiff, D.W.; Cho, D.H.; Chan, S.H.

    1985-01-01

    A kinematic wave analysis of fog sedimentation is employed to relate growth of a fog condensate deposit layer to radiation generated fog formation rates. The increase of surface radiation absorptivity with deposit layer thickness promotes a feedback mechanism for higher growth rates, which is evaluated in detail

  6. Discrete breathers in Bose–Einstein condensates

    International Nuclear Information System (INIS)

    Franzosi, Roberto; Politi, Antonio; Livi, Roberto; Oppo, Gian-Luca

    2011-01-01

    Discrete breathers, originally introduced in the context of biopolymers and coupled nonlinear oscillators, are also localized modes of excitation of Bose–Einstein condensates (BEC) in periodic potentials such as those generated by counter-propagating laser beams in an optical lattice. Static and dynamical properties of breather states are analysed in the discrete nonlinear Schrödinger equation that is derived in the limit of deep potential wells, tight-binding and the superfluid regime of the condensate. Static and mobile breathers can be formed by progressive re-shaping of initial Gaussian wave-packets or by transporting atomic density towards dissipative boundaries of the lattice. Static breathers generated via boundary dissipations are determined via a transfer-matrix approach and discussed in the two analytic limits of highly localized and very broad profiles. Mobile breathers that move across the lattice are well approximated by modified analytical expressions derived from integrable models with two independent parameters: the core-phase gradient and the peak amplitude. Finally, possible experimental realizations of discrete breathers in BEC in optical lattices are discussed in the presence of residual harmonic trapping and in interferometry configurations suitable to investigate discrete breathers' interactions. (invited article)

  7. Ice condenser testing facility and plans

    International Nuclear Information System (INIS)

    Kannberg, L.D.; Ross, B.A.; Eschbach, E.J.; Ligotke, M.W.

    1987-01-01

    A facility is being constructed to experimentally validate the ICEDF computer code. The code was developed to estimate the extent of fission product retention in the ice compartments of pressurized water reactor ice condenser containment systems during severe accidents. The design and construction of the facility is based on a test design that addresses the validation needs of the code for conditions typical of those expected to occur during severe pressurized water reactor accidents. Detailed facility design has followed completion of a test design (i.e., assembled test cases each involving a different set of aerosol and thermohydraulic flow conditions). The test design was developed with the aid of statistical test design software and was scrutinized for applicability with the aid of ICEDF simulations. The test facility will incorporate a small section of a prototypic ice condenser (e.g., a cross section comprising the equivalent of four 1-ft-diameter ice baskets to their full prototypic height of 48 ft). The development of the test design, the detailed facility design, and the construction progress are described in this paper

  8. Collaboration in Australian condensed matter physics research

    International Nuclear Information System (INIS)

    Cushion, J.D.

    1998-01-01

    Full text: This year marks the 'coming of age' of the annual Condensed Matter Physics Meetings which has constituted possibly the most successful physics series which has been run in Australia and New Zealand. The conferences have become colloquially known as the 'Wagga conferences' to the community, leading to such strange but interpretable phrases as 'Wagga is in New Zealand this year'. It seems an appropriate time to take stock of some of the changes which have taken place in Australian condensed matter physics research over the past 21 years. Statistics will be presented on some of the trends over this time, using the Wagga abstract books as the data source. Particular emphasis will be placed on the increase in collaborative research which has occurred, fuelled by a combination of government policies, reduction in resources and increasing complexity of some of the research projects. Collaborative papers now frequently include authors from more than one university as well as from CSIRO, ANSTO/AINSE, other government and semi-government laboratories and private industry. None of these occurred in the 'early days' but most would agree that the health of the discipline has been improved by the change. It is also appropriate to point out the role of the Wagga conferences in fostering these collaborations by bringing together the groups so that they could meet, interact and discover which people had the missing expertise to make a particular project viable

  9. NUCLEAR CONDENSATE AND HELIUM WHITE DWARFS

    Energy Technology Data Exchange (ETDEWEB)

    Bedaque, Paulo F.; Berkowitz, Evan [Maryland Center for Fundamental Physics, Department of Physics, University of Maryland, College Park, MD (United States); Cherman, Aleksey, E-mail: bedaque@umd.edu, E-mail: evanb@umd.edu, E-mail: a.cherman@damtp.cam.ac.uk [Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Cambridge CB3 0WA (United Kingdom)

    2012-04-10

    We consider a high-density region of the helium phase diagram, where the nuclei form a Bose-Einstein condensate rather than a classical plasma or a crystal. Helium in this phase may be present in helium-core white dwarfs. We show that in this regime there is a new gapless quasiparticle not previously noticed, arising when the constraints imposed by gauge symmetry are taken into account. The contribution of this quasiparticle to the specific heat of a white dwarf core turns out to be comparable in a range of temperatures to the contribution from the particle-hole excitations of the degenerate electrons. The specific heat in the condensed phase is two orders of magnitude smaller than in the uncondensed plasma phase, which is the ground state at higher temperatures, and four orders of magnitude smaller than the specific heat that an ion lattice would provide, if formed. Since the specific heat of the core is an important input for setting the rate of cooling of a white dwarf star, it may turn out that such a change in the thermal properties of the cores of helium white dwarfs has observable implications.

  10. Exhaled Breath Condensate: Technical and Diagnostic Aspects.

    Science.gov (United States)

    Konstantinidi, Efstathia M; Lappas, Andreas S; Tzortzi, Anna S; Behrakis, Panagiotis K

    2015-01-01

    The aim of this study was to evaluate the 30-year progress of research on exhaled breath condensate in a disease-based approach. We searched PubMed/Medline, ScienceDirect, and Google Scholar using the following keywords: exhaled breath condensate (EBC), biomarkers, pH, asthma, gastroesophageal reflux (GERD), smoking, COPD, lung cancer, NSCLC, mechanical ventilation, cystic fibrosis, pulmonary arterial hypertension (PAH), idiopathic pulmonary fibrosis, interstitial lung diseases, obstructive sleep apnea (OSA), and drugs. We found 12600 related articles in total in Google Scholar, 1807 in ScienceDirect, and 1081 in PubMed/Medline, published from 1980 to October 2014. 228 original investigation and review articles were eligible. There is rapidly increasing number of innovative articles, covering all the areas of modern respiratory medicine and expanding EBC potential clinical applications to other fields of internal medicine. However, the majority of published papers represent the results of small-scale studies and thus current knowledge must be further evaluated in large cohorts. In regard to the potential clinical use of EBC-analysis, several limitations must be pointed out, including poor reproducibility of biomarkers and absence of large surveys towards determination of reference-normal values. In conclusion, contemporary EBC-analysis is an intriguing achievement, but still in early stage when it comes to its application in clinical practice.

  11. Condensation phenomena in a turbine blade passage

    International Nuclear Information System (INIS)

    Skillings, S.A.

    1989-02-01

    The mechanisms associated with the formation and growth of water droplets in the large low-pressure (LP) turbines used for electrical power generation are poorly understood and recent measurements have indicated that an unusually high loss is associated with the initial nucleation of these droplets. In order to gain an insight into the phenomena which arise in the turbine situation, some experiments were performed to investigate the behaviour of condensing steam flows in a blade passage. This study has revealed the fundamental significance of droplet nucleation in modifying the single-phase flow structure and results are presented which show the change in shock wave pattern when inlet superheat and outlet Mach number are varied. The trailing-edge shock wave structure appears considerably more robust towards variation of inlet superheat than purely one-dimensional considerations may suggest and the inadequacies of adopting a one-dimensional theory to analyse multi-dimensional condensing flows are demonstrated. Over a certain range of outlet Mach numbers an oscillating shock wave will establish in the throat region of the blade passage and this has been shown to interact strongly with droplet nucleation, resulting in a considerably increased mean droplet size. The possible implications of these results for turbine performance are also discussed. (author)

  12. The order of condensation in capillary grooves

    International Nuclear Information System (INIS)

    Rascón, Carlos; Parry, Andrew O; Nürnberg, Robert; Pozzato, Alessandro; Tormen, Massimo; Bruschi, Lorenzo; Mistura, Giampaolo

    2013-01-01

    We consider capillary condensation in a deep groove of width L. The transition occurs at a pressure p co (L) described, for large widths, by the Kelvin equation p sat − p co (L) = 2σcosθ/L, where θ is the contact angle at the side walls and σ is the surface tension. The order of the transition is determined by the contact angle of the capped end θ cap ; it is continuous if the liquid completely wets the cap, and first-order otherwise. When the transition is first-order, corner menisci at the bottom of the capillary lead to a pronounced metastability, determined by a complementary Kelvin equation Δp(L) = 2σsinθ cap /L. On approaching the wetting temperature of the capillary cap, the corner menisci merge and a single meniscus unbinds from the bottom of the groove. Finite-size scaling shifts, crossover behaviour and critical singularities are determined at mean-field level and beyond. Numerical and experimental results showing the continuous nature of condensation for θ cap = 0 and the influence of corner menisci on adsorption isotherms are presented. (fast track communication)

  13. Condensed matter view of giant resonance phenomena

    International Nuclear Information System (INIS)

    Zangwill, A.

    1987-01-01

    The intent of this article is to present a view of giant resonance phenomena (an essentially atomic phenomenon) from the perspective of a condensed matter physicist with an interest in the optical properties of matter. As we shall see, this amounts to a particular prejudice about how one should think about many-body effects in a system of interacting electrons. Some of these effects are special to condensed matter systems and will be dealt with in the second half of this paper. However, it turns out that the authors view of the main ingredient to a giant resonance differs significantly from that normally taken by scientists trained in the traditional methods of atomic physics. Therefore, in the first section the author will take advantage of the fact that his contribution to this volume was composed and delivered to the publishers somewhat after the conclusion of the School (rather than before as requested by the organizers) and try to clearly distinguish the differences of opinion presented by the lecturers from the unalterable experimental facts. 46 references, 9 figures

  14. NUCLEAR CONDENSATE AND HELIUM WHITE DWARFS

    International Nuclear Information System (INIS)

    Bedaque, Paulo F.; Berkowitz, Evan; Cherman, Aleksey

    2012-01-01

    We consider a high-density region of the helium phase diagram, where the nuclei form a Bose-Einstein condensate rather than a classical plasma or a crystal. Helium in this phase may be present in helium-core white dwarfs. We show that in this regime there is a new gapless quasiparticle not previously noticed, arising when the constraints imposed by gauge symmetry are taken into account. The contribution of this quasiparticle to the specific heat of a white dwarf core turns out to be comparable in a range of temperatures to the contribution from the particle-hole excitations of the degenerate electrons. The specific heat in the condensed phase is two orders of magnitude smaller than in the uncondensed plasma phase, which is the ground state at higher temperatures, and four orders of magnitude smaller than the specific heat that an ion lattice would provide, if formed. Since the specific heat of the core is an important input for setting the rate of cooling of a white dwarf star, it may turn out that such a change in the thermal properties of the cores of helium white dwarfs has observable implications.

  15. The order of condensation in capillary grooves.

    Science.gov (United States)

    Rascón, Carlos; Parry, Andrew O; Nürnberg, Robert; Pozzato, Alessandro; Tormen, Massimo; Bruschi, Lorenzo; Mistura, Giampaolo

    2013-05-15

    We consider capillary condensation in a deep groove of width L. The transition occurs at a pressure p(co)(L) described, for large widths, by the Kelvin equation p(sat) - p(co)(L) = 2σ cosθ/L, where θ is the contact angle at the side walls and σ is the surface tension. The order of the transition is determined by the contact angle of the capped end θcap; it is continuous if the liquid completely wets the cap, and first-order otherwise. When the transition is first-order, corner menisci at the bottom of the capillary lead to a pronounced metastability, determined by a complementary Kelvin equation Δp(L) = 2σ sinθcap/L. On approaching the wetting temperature of the capillary cap, the corner menisci merge and a single meniscus unbinds from the bottom of the groove. Finite-size scaling shifts, crossover behaviour and critical singularities are determined at mean-field level and beyond. Numerical and experimental results showing the continuous nature of condensation for θcap = 0 and the influence of corner menisci on adsorption isotherms are presented.

  16. The Solar Photosphere: Evidence for Condensed Matter

    Directory of Open Access Journals (Sweden)

    Robitaille P. M.

    2006-04-01

    Full Text Available The stellar equations of state treat the Sun much like an ideal gas, wherein the photosphere is viewed as a sparse gaseous plasma. The temperatures inferred in the solar interior give some credence to these models, especially since it is counterintuitive that an object with internal temperatures in excess of 1 MK could be existing in the liquid state. Nonetheless, extreme temperatures, by themselves, are insufficient evidence for the states of matter. The presence of magnetic fields and gravity also impact the expected phase. In the end, it is the physical expression of a state that is required in establishing the proper phase of an object. The photosphere does not lend itself easily to treatment as a gaseous plasma. The physical evidence can be more simply reconciled with a solar body and a photosphere in the condensed state. A discussion of each physical feature follows: (1 the thermal spectrum, (2 limb darkening, (3 solar collapse, (4 the solar density, (5 seismic activity, (6 mass displacement, (7 the chromosphere and critical opalescence, (8 shape, (9 surface activity, (10 photospheric/coronal flows, (11 photospheric imaging, (12 the solar dynamo, and (13 the presence of Sun spots. The explanation of these findings by the gaseous models often requires an improbable combination of events, such as found in the stellar opacity problem. In sharp contrast, each can be explained with simplicity by the condensed state. This work is an invitation to reconsider the phase of the Sun.

  17. The development of air cooled condensation systems

    International Nuclear Information System (INIS)

    Bodas, J.

    1990-01-01

    EGI - Contracting/Engineering has had experience with the development of air cooled condensing systems since the 1950's. There are two accepted types of dry cooling systems,the direct and the indirect ones. Due to the fact that the indirect system has several advantages over the direct one, EGI's purpose was to develop an economic, reliable and efficient type of indirect cooling system, both for industrial and power station applications. Apart from system development, the main components of dry cooling plant have been developed as well. These are: the water-to-air heat exchangers; the direct contact (DC, or jet) condenser; the cooling water circulating pumps and recovery turbines; and the peak cooling/preheating units. As a result of this broad development work which was connected with intensive market activity, EGI has supplied about 50% of the dry cooling plants employed for large power stations all over the world. This means that today the cumulated capacity of power units using Heller type dry cooling systems supplied and contracted by EGI is over 6000 MW

  18. Exhaled Breath Condensate: Technical and Diagnostic Aspects

    Directory of Open Access Journals (Sweden)

    Efstathia M. Konstantinidi

    2015-01-01

    Full Text Available Purpose. The aim of this study was to evaluate the 30-year progress of research on exhaled breath condensate in a disease-based approach. Methods. We searched PubMed/Medline, ScienceDirect, and Google Scholar using the following keywords: exhaled breath condensate (EBC, biomarkers, pH, asthma, gastroesophageal reflux (GERD, smoking, COPD, lung cancer, NSCLC, mechanical ventilation, cystic fibrosis, pulmonary arterial hypertension (PAH, idiopathic pulmonary fibrosis, interstitial lung diseases, obstructive sleep apnea (OSA, and drugs. Results. We found 12600 related articles in total in Google Scholar, 1807 in ScienceDirect, and 1081 in PubMed/Medline, published from 1980 to October 2014. 228 original investigation and review articles were eligible. Conclusions. There is rapidly increasing number of innovative articles, covering all the areas of modern respiratory medicine and expanding EBC potential clinical applications to other fields of internal medicine. However, the majority of published papers represent the results of small-scale studies and thus current knowledge must be further evaluated in large cohorts. In regard to the potential clinical use of EBC-analysis, several limitations must be pointed out, including poor reproducibility of biomarkers and absence of large surveys towards determination of reference-normal values. In conclusion, contemporary EBC-analysis is an intriguing achievement, but still in early stage when it comes to its application in clinical practice.

  19. Equation of state of warm condensed matter

    Energy Technology Data Exchange (ETDEWEB)

    Barbee, T.W., III; Young, D.A.; Rogers, F.J.

    1998-03-01

    Recent advances in computational condensed matter theory have yielded accurate calculations of properties of materials. These calculations have, for the most part, focused on the low temperature (T=0) limit. An accurate determination of the equation of state (EOS) at finite temperature also requires knowledge of the behavior of the electron and ion thermal pressure as a function of T. Current approaches often interpolate between calculated T=0 results and approximations valid in the high T limit. Plasma physics-based approaches are accurate in the high temperature limit, but lose accuracy below T{approximately}T{sub Fermi}. We seek to ``connect up`` these two regimes by using ab initio finite temperature methods (including linear-response[1] based phonon calculations) to derive an equation of state of condensed matter for T{<=}T{sub Fermi}. We will present theoretical results for the principal Hugoniot of shocked materials, including carbon and aluminum, up to pressures P>100 GPa and temperatures T>10{sup 4}K, and compare our results with available experimental data.

  20. Open problems in condensed matter physics, 1987

    International Nuclear Information System (INIS)

    Falicov, L.M.

    1988-08-01

    The 1970's and 1980's can be considered the third stage in the explosive development of condensed matter physics. After the very intensive research of the 1930's and 1940's, which followed the formulation of quantum mechanics, and the path-breaking activity of the 1950's and 1960's, the problems being faced now are much more complex and not always susceptible to simple modelling. The (subjectively) open problems discussed here are: high temperature superconductivity, its properties and the possible new mechanisms which lead to it; the integral and fractional quantum Hall effects; new forms of order in condensed-matter systems; the physics of disorder, especially the problem of spin glasses; the physics of complex anisotropic systems; the theoretical prediction of stable and metastable states of matter; the physics of highly correlated states (heavy fermions); the physics of artificially made structures, in particular heterostructures and highly metastable states of matter; the determination of the microscopic structure of surfaces; and chaos and highly nonlinear phnomena. 82 refs

  1. Quark and gluon condensate in vacuum

    International Nuclear Information System (INIS)

    Vajnshtejn, A.I.; Zakharov, V.I.; Shifman, M.A.

    1979-01-01

    The mechanism of quark confinement has been reviewed. The fact that coloured particles in a free state cannot be observed is connected with specific properties of vacuum in quantum chromodynamics. The basic hypothesis consists in the existence of vacuum fields, quark and gluon condensates, which affect the coloured objects. The vacuum transparent relative to noncharged ''white'' states serves as a source of the force acting upon the coloured particles. It has been a sucess to examine strictly the action of the vacuum fields on quarks when the distance between them is relatively small and the force of the vacuum fields on quarks is relatively small too. It is shown that the interaction with the vacuum fields manifests itself earlier than the forces connected with the gluon exchange do. It is assumed that the vacuum condensate of quarks and gluons and its relation to properties of resonances and to the bag model exist in reality. The dispersion sum rules are used for calculating masses and lepton widths of resonances

  2. Condensed matter physics aspects of electrochemistry

    International Nuclear Information System (INIS)

    Tosi, M.P.; Kornyshev, A.A.

    1991-01-01

    This volume collects the proceedings of the Working Party on ''Electrochemistry: Condensed Matter, Atomic and Molecular Physics Aspects'', held for two weeks in the summer of 1990 at the International Centre for Theoretical Physics (ICTP) in Trieste. The goal of the meeting was to discuss those areas of electrochemistry that are accessible to the modern methods of theoretical condensed matter, atomic and molecular physics, in order to stimulate insight and deeper involvement by theoretical physicists into the field. The core of the ICTP Working Party was a set of topically grouped plenary lectures, accompanied by contributed seminars and by the formulation of joint research projects. In the tradition of the ICTP, it was not a meeting of pure theoreticians: about half of the lecturers were professional experimentalists - experts in electrochemistry, physical chemistry, surface science, technical applications. A set of topics was chosen for discussion at the meeting: Liquids, solvation, solutions; The interface (structure, characterization, electric properties, adsorption); Electrodynamics, optics, photo-emission; Charge transfer kinetics (homogeneous and heterogeneous reactions and processes); Superconducting electrodes; Fractal electrodes; Applied research (energy conversion and power sources, electrocatalysis, electroanalysis of turbulent flows). Refs, figs and tabs

  3. Aspects of Landau condensation in atomic physics

    International Nuclear Information System (INIS)

    Gay, J.C.

    1980-01-01

    Some aspects of Landau condensation in atomic physics are reviewed both as regards current work on Rydberg states under laboratory conditions and from the viewpoint of the prospects of spontaneous decay of neutral vacuum with superheavy elements. The characteristics of the hydrogen-atom spectrum in a strong magnetic field are presented and discussed using essentially semiclassical arguments. Some schematic attempt at a global interpretation of the Rydberg spectrum near the ionization limit is also given. Then the action of an electric field on the quasi-Landau spectrum is discussed. The conditions for spontaneous production of positrons from neutral vacuum decay with superheavy elements are reconsidered for the case when the system experiences ultrastrong magnetic fields, as in pulsars and white dwarfs. It is shown that spontaneous decay of neutral vacuum may occur at lower Z values than 169. The possible importance of such effects during heavy-ion collisions is briefly discussed. We deal with some qualitative trends of the problem of an atom in a magnetic field with particular emphasis on diamagnetic effects. In the last few years, we have had the capability of making accurate experimental investigations of Rydberg atoms, and perhaps in the future we will develop fundamentally new means of studying heavy-ion collisions. Accordingly it seems of interest to make qualitative remarks regarding the present state of the problem and the possible importance of Landau condensation in various domains of atomic physics now under active development. (author)

  4. Modeling the Phase Composition of Gas Condensate in Pipelines

    Science.gov (United States)

    Dudin, S. M.; Zemenkov, Yu D.; Shabarov, A. B.

    2016-10-01

    Gas condensate fields demonstrate a number of thermodynamic characteristics to be considered when they are developed, as well as when gas condensate is transported and processed. A complicated phase behavior of the gas condensate system, as well as the dependence of the extracted raw materials on the phase state of the deposit other conditions being equal, is a key aspect. Therefore, when designing gas condensate lines the crucial task is to select the most appropriate methods of calculating thermophysical properties and phase equilibrium of the transported gas condensate. The paper describes a physical-mathematical model of a gas-liquid flow in the gas condensate line. It was developed based on balance equations of conservation of mass, impulse and energy of the transported medium within the framework of a quasi-1D approach. Constitutive relationships are given separately, and practical recommendations on how to apply the research results are provided as well.

  5. Targeted Functionalization of Nanoparticle Thin Films via Capillary Condensation

    KAUST Repository

    Gemici, Zekeriyya; Schwachulla, Patrick I.; Williamson, Erik H.; Rubner, Michael F.; Cohen, Robert E.

    2009-01-01

    Capillary condensation, an often undesired natural phenomenon in nanoporous materials, was used advantageously as a universal functionalization strategy in nanoparticle thin films assembled layer-by-layer. Judicious choice of nanoparticle (and therefore pore) size allowed targeted capillary condensation of chemical vapors of both hydrophilic and hydrophobic molecules across film thickness. Heterostructured thin films with modulated refractive index profiles produced in this manner exhibited broadband antireflection properties with an average reflectance over the visible region of the spectrum of only 0.4%. Capillary condensation was also used to modify surface chemistry and surface energy. Photosensitive capillary-condensates were UV-cross-linked in situ. Undesired adventitious condensation of humidity could be avoided by condensation of hydrophobic materials such as poly(dimethyl siloxane). © 2009 American Chemical Society.

  6. Targeted Functionalization of Nanoparticle Thin Films via Capillary Condensation

    KAUST Repository

    Gemici, Zekeriyya

    2009-03-11

    Capillary condensation, an often undesired natural phenomenon in nanoporous materials, was used advantageously as a universal functionalization strategy in nanoparticle thin films assembled layer-by-layer. Judicious choice of nanoparticle (and therefore pore) size allowed targeted capillary condensation of chemical vapors of both hydrophilic and hydrophobic molecules across film thickness. Heterostructured thin films with modulated refractive index profiles produced in this manner exhibited broadband antireflection properties with an average reflectance over the visible region of the spectrum of only 0.4%. Capillary condensation was also used to modify surface chemistry and surface energy. Photosensitive capillary-condensates were UV-cross-linked in situ. Undesired adventitious condensation of humidity could be avoided by condensation of hydrophobic materials such as poly(dimethyl siloxane). © 2009 American Chemical Society.

  7. Calcium ions function as a booster of chromosome condensation.

    Science.gov (United States)

    Phengchat, Rinyaporn; Takata, Hideaki; Morii, Kenichi; Inada, Noriko; Murakoshi, Hideji; Uchiyama, Susumu; Fukui, Kiichi

    2016-12-02

    Chromosome condensation is essential for the faithful transmission of genetic information to daughter cells during cell division. The depletion of chromosome scaffold proteins does not prevent chromosome condensation despite structural defects. This suggests that other factors contribute to condensation. Here we investigated the contribution of divalent cations, particularly Ca 2+ , to chromosome condensation in vitro and in vivo. Ca 2+ depletion caused defects in proper mitotic progression, particularly in chromosome condensation after the breakdown of the nuclear envelope. Fluorescence lifetime imaging microscopy-Förster resonance energy transfer and electron microscopy demonstrated that chromosome condensation is influenced by Ca 2+ . Chromosomes had compact globular structures when exposed to Ca 2+ and expanded fibrous structures without Ca 2+ . Therefore, we have clearly demonstrated a role for Ca 2+ in the compaction of chromatin fibres.

  8. Gas condensate--raw material for producing liquid paraffin hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Aliyeva, R.B.; Alikishi-Zade, G.Yu.; Kuliyev, A.M.; Leonidov, A.N.; Pereverzev, A.N.

    1980-01-01

    The problem of efficient utilization of gas condensates as raw material for removal of a valuable product, liquid paraffins, is examined. A classification of gas condensates is given which is used as raw material for removing these hydrocarbons: gas condensate with high content of n-alkanes (25-40 mass percent), with average content (18-25 mass percent), with low content (12-18 mass percent), light weight fractions compositions, which do not contain fractions up to 200/sup 0/, and also, content ofless than 12% n-alkanes. Gas condensate I-III groups are 30% of the total reserve of gas condensate. Liquid paraffins hydrocarbons, produced from fractions of diesel fuel, which has been removed from Shatlyk gas condensate under conditions which simulate virtual processes of caramide deparaffinization meet all requirements without additional refining.

  9. Entropy generation in a condenser and related correlations

    Directory of Open Access Journals (Sweden)

    Askowski Rafał

    2015-06-01

    Full Text Available The paper presents an analysis of relations describing entropy generation in a condenser of a steam unit. Connections between entropy generation, condenser ratio, and heat exchanger effectiveness, as well as relations implied by them are shown. Theoretical considerations allowed to determine limits of individual parameters which describe the condenser operation. Various relations for average temperature of the cold fluid were compared. All the proposed relations were verified against data obtained using a simulator and actual measurement data from a 200 MW unit condenser. Based on data from a simulator it was examined how the sum of entropy rates, steam condenser effectiveness, terminal temperature difference and condenser ratio vary with the change in the inlet cooling water temperature, mass flow rate of steam and the cooling water mass flow rate.

  10. Targeted functionalization of nanoparticle thin films via capillary condensation.

    Science.gov (United States)

    Gemici, Zekeriyya; Schwachulla, Patrick I; Williamson, Erik H; Rubner, Michael F; Cohen, Robert E

    2009-03-01

    Capillary condensation, an often undesired natural phenomenon in nanoporous materials, was used advantageously as a universal functionalization strategy in nanoparticle thin films assembled layer-by-layer. Judicious choice of nanoparticle (and therefore pore) size allowed targeted capillary condensation of chemical vapors of both hydrophilic and hydrophobic molecules across film thickness. Heterostructured thin films with modulated refractive index profiles produced in this manner exhibited broadband antireflection properties with an average reflectance over the visible region of the spectrum of only 0.4%. Capillary condensation was also used to modify surface chemistry and surface energy. Photosensitive capillary-condensates were UV-cross-linked in situ. Undesired adventitious condensation of humidity could be avoided by condensation of hydrophobic materials such as poly(dimethyl siloxane).

  11. Local condensate depletion at trap center under strong interactions

    Science.gov (United States)

    Yukalov, V. I.; Yukalova, E. P.

    2018-04-01

    Cold trapped Bose-condensed atoms, interacting via hard-sphere repulsive potentials are considered. Simple mean-field approximations show that the condensate distribution inside a harmonic trap always has the shape of a hump with the maximum condensate density occurring at the trap center. However, Monte Carlo simulations at high density and strong interactions display the condensate depletion at the trap center. The explanation of this effect of local condensate depletion at trap center is suggested in the frame of self-consistent theory of Bose-condensed systems. The depletion is shown to be due to the existence of the anomalous average that takes into account pair correlations and appears in systems with broken gauge symmetry.

  12. Assessment of Condenser Design in the Cooling System of PWR

    International Nuclear Information System (INIS)

    Sukmanto Dibyo

    2008-01-01

    This paper explains various cases related to the problem of condenser design principle. Condenser equipment is circuit component of cooling that is very important. Steam that goes down from the turbine, flowing to the condenser and the steam is condensate to be water. Step of design is beginning from identification of problem until mechanic design. Usually, the condenser is designed by conservative certain levels, as well as thermal aspect or mechanic. Beside that, the design analysis is also anticipated to the existing of degradation due to aging therefore safety aspect and requirement are accepted. The assessment that related to the condenser design has been discussed. Most important aspect is obtaining of performances. Beside that, the discussion is also described about design method and that complication should consider aspect of thermal design, physics, economic, aspect of corrosion and others factors. (author)

  13. Comparison of condensation correlations in CATHARE for modelling isolation condenser experiment

    International Nuclear Information System (INIS)

    Sorjonen, J.; Kalli, H.

    1996-01-01

    CATHARE is a thermal-hydraulic computer code developed at the Centre d'Etudes Nucleaires de Grenoble (CENG) for nuclear power plant safety analysis. Behaviour of a new Cathare condensation correlation have been studied. The code has been applied to Isolation Condenser (IC) experiment conducted in PIPER-ONE facility. PIPER-ONE simulates a General Electric BWR-6 with volume and height scaling ratios 1/2200 and 1/1, respectively. The facility is installed at Dipartimento di Costruzioni Meccaniche e Nucleari of Pisa University. The facility was equipped with an once-through heat exchanger immersed in a pool of ambient temperature water, installed roughly 10 m above the core, in the aim to reproduce qualitatively the phenomenologies expected for Isolation Condenser in the Simplified BWR (SBWR). Experiment PO-IC-02 included two subsequent power levels with initial pressure of 5.1 MPa. The IC was active during the whole experiment except in the time period between the two different power levels. A previous calculation of above mentioned experiment by Cathare2 V1.3E showed some lacks in the condensation correlation of the code. A new correlation has been developed in Centre d'Etudes Nucleaires de Grenoble (CENG). The new calculation of the PO-IC-02 experiment by Cathare2 Vl.3U 1 with the new correlation gave results consistent with the experiment in the condensing zone of the IC. Also the overall pressure trend was reproduced with estimated heat losses to the environment. A comparison with previously obtained Relap5/Mod3. 1 results is also shown in the present document. (author) (18 refs.)

  14. EVALUATION OF SOLVENTS EFFICIENCY IN CONDENSATE BANKING REMOVAL

    OpenAIRE

    CORREA, TOMAS; TIAB, DJEBBAR; RESTREPO, DORA PATRICIA

    2009-01-01

    This work describes experimental design and tests performed to simulate gas condensate reservoir conditions below dew point in the laboratory using three different compositions of synthetic gas condensate. Methanol, propanol and methylene chloride are the solvents used to remove the condensate banking and improve the gas effective permeability near to the wellbore. Solvents are injected in Berea sandstone rock with similar petrophysical properties in order to compare the efficiency at removin...

  15. Importance of water Influx and waterflooding in Gas condensate reservoir

    OpenAIRE

    Ali, Faizan

    2014-01-01

    The possibility of losing valuable liquid and lower gas well deliverability have made gas condensate reservoirs very important and extra emphasizes are made to optimize hydrocarbon recovery from a gas condensate reservoir. Methods like methanol treatments, wettability alteration and hydraulic fracturing are done to restore the well deliverability by removing or by passing the condensate blockage region. The above mentioned methods are applied in the near wellbore region and only improve the w...

  16. Collapsing dynamics of attractive Bose-Einstein condensates

    DEFF Research Database (Denmark)

    Bergé, L.; Juul Rasmussen, J.

    2002-01-01

    The self-similar collapse of 3D and quasi-2D atom condensates with negative scattering length is examined. 3D condensates are shown to blow up following the scenario of weak collapse, for which 3-body recombination weakly dissipates the atoms. In contrast, 2D condensates undergo a strong collapse......, that absorbs a significant amount of particles. (C) 2002 Elsevier Science B.V. All rights reserved....

  17. Stabilization of matter wave solitons in weakly coupled atomic condensates

    International Nuclear Information System (INIS)

    Radha, R.; Vinayagam, P.S.

    2012-01-01

    We investigate the dynamics of a weakly coupled two component Bose–Einstein condensate and generate bright soliton solutions. We observe that when the bright solitons evolve in time, the density of the condensates shoots up suddenly by virtue of weak coupling indicating the onset of instability in the dynamical system. However, this instability can be overcome either through Feshbach resonance by tuning the temporal scattering length or by suitably changing the time dependent coupling coefficient, thereby extending the lifetime of the condensates.

  18. Hot atom chemistry of monovalent atoms in organic condensed phases

    International Nuclear Information System (INIS)

    Stoecklin, G.

    1975-01-01

    The advantages and disadvantages of hot atom studies in condensed organic phases are considered, and recent advances in condensed phase organic hot atom chemistry of recoil tritium and halogen atoms are discussed. Details are presented of the present status and understanding of liquid phase hot atom chemistry and also that of organic solids. The consequences of the Auger effect in condensed organic systems are also considered. (author)

  19. A simple air-cooled reflux condenser for laboratory use

    International Nuclear Information System (INIS)

    Boult, K.A.

    1979-10-01

    This Memorandum describes the design of a simple compact air-cooled reflux condenser suitable for gloveboxes, cells or other locations where the provision of cooling water presents a problem. In a typical application the condenser functioned satisfactorily when used to condense water from a flask heated by a 100 watt mantle. There was no measurable loss of water from the boiling flask in 100 hours. (author)

  20. Dimensioning of emergency condensers in accordance with safety requirements

    Energy Technology Data Exchange (ETDEWEB)

    Palavecino, C [SIEMENS, Energieerzeugung, Offenbach (Germany)

    1996-12-01

    The emergency condensers are heat exchangers consisting of a parallel arrangement of horizontal U-tubes between two common heads. The tope header is connected via piping to the reactor vessel steam space, while the lower header is connected to the reactor vessel below the reactor vessel water level. The heat exchangers are located in a pool filled with cold water. The emergency condensers and the reactor vessel thus form a system of communicating pipes. At normal reactor water level, the emergency condensers are flooded with cold, non-flowing water. No heat transfer takes place in this condition. If there is a drop in the reactor water level, the heat exchanging surfaces are gradually uncovered and the incoming steam condenses on the cold surfaces. The cold condensate in returned to the reactor vessel. In this way, heat is removed from the reactor vessel and water simultaneously supplied to the reactor vessel. This means that the emergency condensers function as a heat removal system while at the same time serving as HP and LP coolant injection systems. The emergency condensers operate with the highest possible degree of passivity imaginable, namely through a drop in the reactor vessel water level alone, requiring neither control systems nor power supply. The design of the emergency condensers must meet the requirements dictated by the thermal and the hydraulic conditions. Taking into consideration a redundancy degree of N + 2, a specific thermal rating of 63 MW per emergency condenser results for a reactor with an output of 2778 MW. The total performance of the emergency condenser system in thus 252 MW, or 9.1% of reactor output. The probability of failure of the emergency condenser of Siemens SWR 1000 is approximately 10{sup -4} per demand, while that of the older emergency condenser designs is approximately 2 to 3 x 10{sup -3} per demand. (author). 7 figs, 2 tabs.