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Sample records for automatizado para epr

  1. Procedimiento automatizado de orientación masiva aptitudinal-vocacional para bachilleres

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    Antonio Boada

    2015-01-01

    Full Text Available Mediante un procedimiento y técnicas educativas, estadísticas y psicométricas, es posible valorar cuantitativamente a nivel nacional, el área aptitudinal (habilidades básicas del estudiante a nivel verbal, numé- rico y lógico-abstracto, y el área vocacional (a través del perfil psicomé- trico de valoración según las fortalezas del carácter del individuo de los bachilleres y estudiantes cursantes del curso introductorio universitario en una institución educativa a nivel superior; esto de forma independien- te a la oferta académica y capacidad logística, a fin de ejecutar un proce- dimiento automatizado de orientación masiva a través del portal web para los futuros estudiantes de carrera de la institución educativa.

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

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    Kenyer Domínguez

    2010-12-01

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

  3. Sistema automatizado para la determinación del estado de maduración en fruta bomba

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    Minelkis Machado Molina

    2015-01-01

    Full Text Available El desarrollo de tecnologías digitales y su aplicación en la agricultura brindan nuevas posibilidades de automatización de procesos tecnológicos. La investigación realizada tiene como objetivo desarrollar una herramienta informática para la determinación no destructiva del estado de maduración en fruta bomba (var. Maradol Roja. Para alcanzar dicho objetivo se emplea la metodología para el diseño del software Proceso Unificado de Desarrollo (RUP. Para el procesamiento de imágenes se utilizan técnicas de reconocimiento de patrones y para la con - vención de modos de color de RGB a Lab se entrena una red neuronal Perceptron multicapas. Entre los principales resultados se presentan la elevada dependencia entre el IC* y el estado de maduración alcanzando un R 2 de 0,91. Se establecen rangos de IC* por estado de maduración, además se obtiene el software SADEM (Sistema Automatizado para Determinar Estado de Maduración que mediante una imagen digital establece el estado de maduración de la fruta bomba variedad Maradol Roja.

  4. Sistema automatizado de tratamiento de datos hidroquímicos para el chequeo de la calidad de las aguas

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    Reguera, E.

    1990-12-01

    Full Text Available The objective of this work is to ilustrate the use of the SAMA automatic system (Water Monitoring Automatic System to aid the water chemical composition control. This system is based in the determination of mathematical relationships between ionic concentration and electric conductivity. The system was developped in Turbo Pascal for IBM compatible microcomputer. The example of application that is presented in this paper correspond with waters from coastal karstic aquifer affected by marine intrusion. This waters are used for citric irrigation.El objetivo de este trabajo es ilustrar el uso del sistema de programas «SAMA» (Sistema Automatizado para el Monitoreo de las Aguas para la ayuda en el control de la composición química de la aguas. El mismo se basa en la determinación de ecuaciones de dependencia matemática entre la concentración iónica y la conductividad eléctrica. Ha sido implementado en lenguaje Turbo Pascal para microcomputadoras IBM compatibles. El ejemplo de aplicación que se presenta corresponde a aguas de un acuífera kárstico litoral afectado por la intrusión marina las cuales se usan en el regadío de cítricos.

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

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    Rodolfo García Bermúdez

    2006-01-01

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

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

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    M.A. Martínez

    2010-09-01

    Full Text Available

     

    RESUMEN

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

    ABSTRACT

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

  7. Sistema automatizado para el control de las inversiones en las redes eléctricas.

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    Maylín Díaz Pardillo

    2015-03-01

    Full Text Available El presente trabajo investigativo abarca las etapas de la automatización del proceso de control en la ejecución de las inversiones que se realizan en las redes del Sistema Electroenergético Nacional, integrado al Sistema Integral de Gestión de Redes de la Unión Eléctrica. Para el desarrollo de la aplicación se llevaron a cabo las etapas del proceso de desarrollo de software, según lo especifica el Proceso Unificado de Desarrollo (RUP, utilizándose como herramienta de modelado para el análisis y diseño: el Enterprise Architect. El software se implementó en Embarcadero RAD Studio 2010 el cual incluye facilidades de desarrollo para aplicaciones Desktop con un diseño de interfaz adecuado a los requerimientos del cliente, se utilizó Object Pascal como lenguaje de programación lo que permitió un código eficiente y para la persistencia de la información se utilizó como Sistema Gestor de Base de Datos: Microsoft SQL Server 2008 R2.

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

    OpenAIRE

    Encinas Martín, Adolfo

    2012-01-01

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

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

    OpenAIRE

    Bossio Pittini, Lino Francisco

    2015-01-01

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

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

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    Ruperto Menayo Antúnez

    2009-06-01

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

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

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    Yanoy Morejón Mesa

    2014-01-01

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

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

    OpenAIRE

    Guillén Sarita, José Felipe

    1990-01-01

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

  13. Sistema automatizado para el diseño de moldes metálicos para la construcción industrializada de viviendas

    OpenAIRE

    Pérez Pacheco, Víctor Manuel

    2015-01-01

    La construcción industrializada es una solución que cada día se generaliza más, debido a las ventajas que ofrece para crear conjuntos habitacionales con altas prestaciones a muy bajo costo y alta productividad. El cuello de botella para la fabricación de los moldes metálicos utilizados en cada nuevo proyecto está en el diseño del molde dado el gran número de elementos que  se requieren y el número muy alto de soluciones posibles. En el  presente artículo se expone la metodología empleada para...

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

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    Juan Eugenio Hernández-Ávila

    2010-10-01

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

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

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    Luis Diego Murillo

    2006-05-01

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

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

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    Carlos A. da S. Braga

    2001-05-01

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

  17. Sistema automatizado de medición de campo lejano

    OpenAIRE

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

    2004-01-01

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

  18. Sistema Automatizado de Lectura Visual de Datos de Medida

    OpenAIRE

    ESTEBAN AVIVAR, ÁNGEL EUGENIO

    2013-01-01

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

  19. Sistema automatizado para la evaluación de la calidad en los laboratorios de diagnóstico con tecnología SUMA

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    Alfredo Rego

    2012-04-01

    Full Text Available El Centro de Inmunoensayo (CIE es una institución dedicada a investigación-producción orientada al desarrollo y producción de reactivos e instrumentos para el diagnóstico médico, basados en técnicas inmunoenzimáticas que aprovechan la gran especificidad de la interacción antígeno-anticuerpo y las ventajas de las reacciones catalizadas por enzimas. Su línea principal es el Sistema Ultra Micro Analítico (SUMA, que consiste en una tecnología integrada por equipos y reactivos para la realización de los análisis inmunoenzimáticos a un bajo costo de ejecución, lo cual lo hace particularmente adecuado para los programas de prevención de la salud, en los que se requiere el procesamiento de un gran número de muestras. Con el objetivo de lograr la garantía de la calidad se han desarrollado durante más de una década diferentes sistemas de software que se han utilizado en el proceso de evaluación de la calidad en el trabajo de los laboratorios. Con el nombre de SAC 2.0, el CIE desarrolló un sistema para el control de la calidad que puede realizar el proceso evaluativo de forma totalmente automatizada, que ofrece prestaciones similares a los sistemas más avanzados que existen actualmente. En este trabajo se describen elementos considerados en su concepción, así como las ventajas obtenidas con la automatización, las cuales demuestran cómo la herramienta desarrollada constituye un componente de vital importancia para el adecuado funcionamiento de los laboratorios de la tecnología SUMA, ubicados en Cuba y en el exterior.

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

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    Milagros Gómez de Gómez

    2004-01-01

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

  1. Sistema automatizado para la gestión del mantenimiento de equipos (módulos patrimonio y órdenes de trabajo

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    Diarelys Medina Peña

    2015-01-01

    Full Text Available Actualmente en la Universidad Agraria de La Habana (UNAH, la gestión del mantenimiento se realiza de forma poco e¿ciente y no responde a la metodología establecida. Lo antes expuesto esta dado porque existe un gran volumen de información a gestionar que en la mayoría de los casos se maneja de forma manual. También se di¿culta el uso de los sistemas de reporte y la ¿abilidad de la información es dudosa. Unido a esto existe una escasa información de los equipos ya sea por pérdidas o deterioro y además no se cuenta con los recursos humanos capacitados para el desarrollo de las tareas de mantenimiento. El presente trabajo se lleva a cabo con el objetivo de mejorar la organi - zación y funcionamiento de la gestión del mantenimiento y reparación de los equipos en la UNAH, destacando la gestión del patrimonio y de las órdenes de trabajo. Utilizando para guiar el proceso de desarrollo la metodología RUP (por sus siglas en inglés Rational Uni¿ed Process con el ¿n de garantizar que la información se encuentre actualizada y que permita tomar decisiones con mayor rapidez a los que lo necesiten.

  2. Sistema automatizado para la gestión del mantenimiento de equipos (módulos administración y solicitud de servicio

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    Yanelis Suárez Fragas

    2015-01-01

    Full Text Available Actualmente en la Universidad Agraria de La Habana (UNAH, la gestión del mantenimiento se realiza de forma poco eficiente y no responde a la metodología establecida. Lo antes expuesto esta dado porque existe un gran volumen de información a gestionar que en la mayoría de los casos se maneja de forma manual. También se dificulta el uso de los sistemas de reporte y la fiabilidad de la información es dudosa. Unido a esto existe una escasa información de los equipos ya sea por pérdidas o deterioro y además no se cuenta con los recursos humanos capacitados para el desarrollo de las tareas de mantenimiento. El presente trabajo se lleva a cabo con el objetivo de mejorar la orga - nización y funcionamiento de la gestión del mantenimiento y reparación de los equipos en la UNAH, destacando la gestión de las solicitudes del servicio de mantenimiento y la administración de los usuarios del mismo. Utilizando para guiar el proceso de desarrollo la metodología RUP (por sus siglas en inglés Rational Unified Process con el fin de garantizar que la información se encuentre actualizada y que permita tomar decisiones con mayor rapidez a los que lo necesiten.

  3. Evaluación comparativa del método automatizado BACTEC MGIT 960 con el método de las proporciones para determinar susceptibilidad a drogas antituberculosas en Chile Comparative evaluation of automated BACTEC MGIT 960 for testing susceptibility of Mycobacterium tuberculosis to antituberculous drugs in Chile

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    Silvana Piffardi F.

    2004-07-01

    Full Text Available Se comparó el método automatizado BACTEC MGIT 960 con el método de las proporciones (MP para la determinación de la susceptibilidad a drogas anti tuberculosas de 275 cepas de Mycobacterium tuberculosis aisladas de 270 pacientes en Chile entre 2001 y 2003. La concordancia del BACTEC MGIT 960 con el MP según las drogas estudiadas fue de: 97,0% para estreptomicina, 98,9% para rifampicina, 97,4% para isoniazida y 98,1% para etambutol. Los porcentajes globales de resistencia a drogas anti-TBC de las 275 cepas de M. tuberculosis estudiadas, determinados por el BACTEC MGIT960 y el MP fueron de 25,1% y 20,4% respectivamente. Esta diferencia no fue estadísticamente significativa. El BACTEC MGIT 960 dió como resistentes 17 cepas que fueron sensibles por el MP, sobrestimándose por este método la información de cepas resistentes. El BACTEC MGIT 960 en nuestra experiencia presentó una muy buena concordancia con el MP permitiendo un notable acortamiento en el tiempo de obtención de los resultados. Sin embargo, la mayor determinación de cepas resistentes por parte de este método requiere de nuevos análisis que permitan conocer los factores que inciden en este fenómenoThe automated BACTEC MGIT 960 system was compared with the method of proportion (MP for testing susceptibility of Mycobacterium tuberculosis to antituberculous drugs. 275 strains of M. tuberculosis isolated in Chile from 270 patients between 2001 and 2003 were tested. Concordance of BACTEC MGIT 960 with MP depending on the antituberculous drug tested was the following: 97.0% for streptomycin, 98,9% for rifampicin, 97,4% for isoniazid and 98,1% for ethambutol. Total resistance to antituberculous drugs of the 275 strains of M. tuberculosis tested varied from 20.4 % assessed by MP to 25.1% evaluated by BACTEC MGIT 960. These differences were not significant (p: ns; t test. BACTEC MGIT 960 yielded 17 strains as resistant. These same 17 strains were detected as sensitives by MP

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

    Directory of Open Access Journals (Sweden)

    V. Luis

    2010-09-01

    Full Text Available

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

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

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

    Directory of Open Access Journals (Sweden)

    Nancy Piloto

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

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-10-15

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

  7. Analysis behaviour of free radicals produced by ionizing radiations in human blood by EPR for biological dosimetry in patients; Analisis del comportamiento de los radicales libre en la radiolisis de la sangre por EPR para dosimetria biologia en pacientes

    Energy Technology Data Exchange (ETDEWEB)

    Mendoza, O. O.; Almanza, A.; Plazas, M. M. C.

    2006-07-01

    In this work is analyzed the biological dosimetry of the free radicals produced by ionizing radiations in human blood obtained by EPR and the biological behaviour of samples In-Vitro, with Rh: O+, in tubes with EDTA (Acid Etilen Diamino Tetracetic) the samples was extracted of the main investigator, these samples were radiated with gammas of ''60Co of a Theratron 780 between plates of PMMA to a depth of Z{sub m}ax of 0.5 cm and between doses 1 to 25 Gy. In these results the behaviors of signal the free radicals presented a increasing a their intensity depending on applied dose, of equal way are results of the biologic dosimetry displayed in sanguineous populations like. White Globules, Red. Platelets etc, to being compared with Resonance Paramagnetic Electronic (EPR). The results show changes in sanguineous populations in high doses (D>10 Gy) in the case of lymphocytes, granulocitos, macusanita, plaquetas, hemoglobina, haematocrit with change similarly in medium and low doses (D>10Gy) in linfocites, platelets, granulocytes, monocytes and the haematocrit. A sanguineous sample without radiating analyzes by EPR giving the presence of signals with values of g=2.13 2,41 in blood. For the first certain value of g authors have associated it to free radicals like: globin (Fe(IV)=0) or Cu''+ incorporated to the ceruloplasmin molecule. (Author)

  8. Metallomic EPR spectroscopy.

    Science.gov (United States)

    Hagen, Wilfred R

    2009-09-01

    Based on explicit definitions of biomolecular EPR spectroscopy and of the metallome, this tutorial review positions EPR in the field of metallomics as a unique method to study native, integrated systems of metallobiomolecular coordination complexes subject to external stimuli. The specific techniques of whole-system bioEPR spectroscopy are described and their historic, recent, and anticipated applications are discussed.

  9. EPR response characterization of drugs excipients for applying in accident dosimetry; Caracterizacao da resposta RPE dos excipientes dos medicamentos para aplicacao em dosimetria de acidente

    Energy Technology Data Exchange (ETDEWEB)

    Marczewski, Barbara S.; Rodrigues Junior, Orlando; Galante, Ocimar L.; Costa, Zelia M. da; Campos, Leticia L. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)

    2002-07-01

    Some drugs are widely used by the population and can be employed to dose retrospective. The carbohydrates (saccharides), commonly used as excipients in the pharmaceutical industry, produce a quantity of free radicals after gamma irradiation, making them useful for dosimetry in emergency or accident situations that imply in dose evaluation from the materials found nearly or in contact with victims. In general, EPR signal from pulverized pills of some drugs are very complex due to the variety of components in the formulation. Because of this fact, some pharmaceutical excipients identified in the pill composition were also analysed by EPR spectrometry. On the counter drugs were studied: Cebion glucose, AAS, Aspirina, Conmel, Lacto-Purga and sugar substitutive ZeroCal. The excipients were: lactose, amide, anhydrous glucose and magnesium stearate. In some samples the number of radicals produced increased with the dose, showing a linear response for a dose range of interest and an adequate sensibility for dosimetry in accident cases.

  10. Medical application of EPR

    International Nuclear Information System (INIS)

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

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

    Directory of Open Access Journals (Sweden)

    Bernardo Parra Restrepo

    1997-06-01

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

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

    Directory of Open Access Journals (Sweden)

    Ginnette Calvo Guillén

    2014-01-01

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

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

    OpenAIRE

    Castro Popoca, Martiniano

    2012-01-01

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

  14. Biomolecular EPR spectroscopy

    CERN Document Server

    Hagen, Wilfred Raymond

    2008-01-01

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

  15. Rapid Frequency Scan EPR

    OpenAIRE

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

    2011-01-01

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

  16. EPR: the nuclear impasse

    International Nuclear Information System (INIS)

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

  17. Communication by EPR devices

    NARCIS (Netherlands)

    Dieks, Dennis

    1982-01-01

    A recent proposal to achieve faster-than-light communication by means of an EPR-type experimental set-up is examined. We demonstrate that such superluminal communication is not possible. The crucial role of the linearity of the quantum mechanical evolution laws in preventing causal anomalies is stre

  18. Estacionamiento Automatizado con Tecnología RFID

    Directory of Open Access Journals (Sweden)

    Eric León Olivares

    2011-01-01

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

  19. Rapid frequency scan EPR.

    Science.gov (United States)

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

    2011-08-01

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

  20. Broadband transmission EPR spectroscopy.

    Directory of Open Access Journals (Sweden)

    Wilfred R Hagen

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

  1. Electron paramagnetic resonance (EPR) biodosimetry

    International Nuclear Information System (INIS)

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

  2. Quantitative EPR A Practitioners Guide

    CERN Document Server

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

    2010-01-01

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

  3. The EPR reactor NDE

    International Nuclear Information System (INIS)

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

  4. EPR of uranium ions

    International Nuclear Information System (INIS)

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

  5. EPR Flamanville 3, Site Management

    International Nuclear Information System (INIS)

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

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

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

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

  7. Reconsidering Bohr's reply to EPR

    CERN Document Server

    Halvorson, H; Halvorson, Hans; Clifton, Rob

    2001-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Marillier, F. [Association Ecologiste Greenpeace (France)

    2008-07-01

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

  9. EPR in B physics and elsewhere

    International Nuclear Information System (INIS)

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

  10. The EPR for North America

    International Nuclear Information System (INIS)

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

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

    Directory of Open Access Journals (Sweden)

    Paulo Guilherme Leser

    2003-06-01

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

  12. EPR dosimetric properties of formates

    International Nuclear Information System (INIS)

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

  13. Software para generación de cuestionarios

    OpenAIRE

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

    2008-01-01

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

  14. EPR-based material modelling of soils

    Science.gov (United States)

    Faramarzi, Asaad; Alani, Amir M.

    2013-04-01

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

  15. EPR project construction cost control

    Energy Technology Data Exchange (ETDEWEB)

    Duflo, D.; Pouget-Abadie, X. [Electricite de France, Centre National d' Equipement Nucleaire, 92 - Montrouge (France); Dufour, A. [Electricite de France (EDF), Service Etudes et Projets Thermique et Nucleaire, 69 - Villeurbanne (France); Kauffmann, G. [Electricite de France (EDF), Centre National d' Equipement de Production d' Electricite, 37 - Tours (France)

    2001-07-01

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

  16. EPR Dosimetry in Irradiated Fingernails

    International Nuclear Information System (INIS)

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

  17. EPR techniques for space biodosimetry

    Energy Technology Data Exchange (ETDEWEB)

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

    1996-12-31

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

  18. EPR of exchange coupled systems

    CERN Document Server

    Bencini, Alessandro

    2012-01-01

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

  19. Overview of LBB implementation for the EPR

    Energy Technology Data Exchange (ETDEWEB)

    Cauquelin, C.

    1997-04-01

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

  20. EPR dosimetry with tooth enamel: A review.

    Science.gov (United States)

    Fattibene, Paola; Callens, Freddy

    2010-11-01

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

  1. EPR dosimetry with tooth enamel: A review

    Energy Technology Data Exchange (ETDEWEB)

    Fattibene, Paola, E-mail: paola.fattibene@iss.i [Istituto Superiore di Sanita, Department of Technology and Health, Viale Regina Elena 299, I-00161 Rome (Italy); Callens, Freddy, E-mail: freddy.callens@ugent.b [Ghent University, Department of Solid State Sciences, Krijgslaan 281-S1, B-9000 Gent (Belgium)

    2010-11-15

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

  2. EPR dosimetry with tooth enamel: A review

    International Nuclear Information System (INIS)

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

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

    Directory of Open Access Journals (Sweden)

    Monica do Carmo Passos

    2001-06-01

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

  4. EPR Dosimetry - Present and Future

    Energy Technology Data Exchange (ETDEWEB)

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

    1999-07-01

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

  5. EPR meeting international safety standards with margin

    International Nuclear Information System (INIS)

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

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

    Directory of Open Access Journals (Sweden)

    William Bertoloni

    2010-08-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1981-01-01

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

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

    International Nuclear Information System (INIS)

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

  9. Nitrosyl hemoglobins: EPR above 80 K

    Energy Technology Data Exchange (ETDEWEB)

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

    1995-03-01

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

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

    OpenAIRE

    Gill, Richard D.

    2015-01-01

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

  11. New loophole for the EPR paradox

    OpenAIRE

    Feldmann, Michel

    1999-01-01

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

  12. Applications of EPR in radiation research

    CERN Document Server

    Lund, Anders

    2014-01-01

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

  13. Sistema de Información para la Cirugía Neonatal

    OpenAIRE

    Trinchet Soler, Rafael M

    1992-01-01

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

  14. EPR Dosimetry: an update and prospective studies

    International Nuclear Information System (INIS)

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

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

    OpenAIRE

    Rivas Montoya, Ernesto

    2014-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Kazuko Yamamoto

    2011-03-01

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

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

    International Nuclear Information System (INIS)

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

  18. Computational and instrumental methods in EPR

    CERN Document Server

    Bender, Christopher J

    2006-01-01

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

  19. EPR study of free radicals in bread

    Science.gov (United States)

    Yordanov, Nicola D.; Mladenova, Ralitsa

    2004-05-01

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

  20. Can EPR non-locality be geometrical?

    Energy Technology Data Exchange (ETDEWEB)

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

    1995-10-01

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

  1. Study of EPR response of PTFE

    International Nuclear Information System (INIS)

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

  2. Aplicación del método de Angstrom para la caracterización térmica de fluidos

    OpenAIRE

    Hernández Rosales, Ernesto

    2014-01-01

    Las técnicas fototérmicas son un grupo de métodos experimentales basados en la medición del calor generado sobre una muestra dada, mismo que está determinado por las propiedades ópticas y térmicas del material [1]. Para llevar a cabo la presente tesis se tuvo que construir un microscopio fototérmico acoplado a un microscopio óptico. Dicho microscopio esta automatizado para diferentes propósitos. Uno de ellos es utilizar su platina de posicionamiento para colocar una celda para caracterización...

  3. EPR spin trapping of protein radicals

    DEFF Research Database (Denmark)

    Davies, Michael Jonathan; Hawkins, Clare L

    2004-01-01

    Electron paramagnetic resonance (EPR) spin trapping was originally developed to aid the detection of low-molecular-mass radicals formed in chemical systems. It has subsequently found widespread use in biology and medicine for the direct detection of radical species formed during oxidative stress...... and via enzymatic reactions. Over the last 15 years this technique has also found increasing use in detecting and identifying radicals formed on biological macromolecules as a result of either radical reactions or enzymatic processes. Though the EPR signals that result from the trapping of large, slowly...

  4. Barium dithionate as an EPR dosemeter.

    Science.gov (United States)

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

    2006-01-01

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

  5. EPR properties of intact and deproteinated dentin

    International Nuclear Information System (INIS)

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

  6. TL and EPR dating: some applications

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-07-01

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

  7. TL and EPR dating: some applications

    International Nuclear Information System (INIS)

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

  8. Identification of irradiated crab using EPR

    Energy Technology Data Exchange (ETDEWEB)

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

    2007-02-15

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

  9. Mast-sipping in EPR trademark plants

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-05-15

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

  10. Oak Ridge EPR and TNS studies

    International Nuclear Information System (INIS)

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

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

    OpenAIRE

    Owono Marti, Daniel

    2011-01-01

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

  12. Aplicación de inteligencia artificial en sistemas automatizados de producción

    OpenAIRE

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

    2000-01-01

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

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

    Indian Academy of Sciences (India)

    2016-08-01

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

  14. Monitoring enzymatic ATP hydrolysis by EPR spectroscopy

    OpenAIRE

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

    2014-01-01

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

  15. EPR-spectroscopic properties of chicory

    International Nuclear Information System (INIS)

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

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

    OpenAIRE

    González Muñoz, Sergio

    2015-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1993-12-31

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

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

    International Nuclear Information System (INIS)

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

  19. Synergistic effect of nanoclay and EPR-g-MA on the properties of nylon6/EPR blends.

    Science.gov (United States)

    Mallick, Sumana; Das, Tanya; Das, C K; Khatua, B B

    2009-05-01

    The effect of EPR-g-MA, nanoclay and a combination of the two on phase morphology and properties of (70/30 w/w) nylon6/EPR blends prepared by melt processing technique has been studied. We found that the number average domain diameter (D(n)) of the dispersed EPR phase in the blend decreased in presence of EPR-g-MA, and clay. This observation indicated that nanoclay could be used as an effective compatibilizer in nylon6/EPR blend. X-ray diffraction study and TEM analysis of the blend/clay nanocomposites revealed the delaminated clay morphology and preferential location of the exfoliated clay platelets in nylon6 phase. Thus, selective dispersion of the clay platelets with delaminated morphology in the matrix phase acted as the barrier and thereby prevented the coalescence of dispersed EPR domains during melt processing. However, addition of nanoclay in the blend did not improve the impact property of the blend. Interestingly, the impact strength of the nylon6/EPR/EPR-g-MA/clay blend was much higher than the nylon6/EPR/EPR-g-MA and nylon6/EPR/clay blends at certain compositions with comparable D(n) values. This could be explained by assuming the presence of delaminated clay platelets at the interface, which were stiffer than the polymers. Hence, the bending energy of the interfaces was high.

  20. EPR spectrum of the Y@C82 metallofullerene isolated in solid argon matrix: hyperfine structure from EPR spectroscopy and relativistic DFT calculations.

    Science.gov (United States)

    Misochko, Eugenii Ya; Akimov, Alexander V; Belov, Vasilii A; Tyurin, Daniil A; Bubnov, Vyacheslav P; Kareev, Ivan E; Yagubskii, Eduard B

    2010-08-21

    The EPR spectrum of the Y@C(82) molecules isolated in solid argon matrix was recorded for the first time at a temperature of 5 K. The isotropic hyperfine coupling constant (hfcc) A(iso) = 0.12 +/- 0.02 mT on the nucleus (89)Y as derived from the EPR spectrum is found in more than two times greater than that obtained in previous EPR measurements in liquid solutions. Comparison of the measured hfcc on a metal atom with that predicted by density-functional theory calculations (PBE/L22) indicate that relativistic method provides good agreement between experiment in solid argon and theory. Analysis of the DFT calculated dipole-dipole hf-interaction tensor and electron spin distribution in the endometallofullerenes with encaged group 3 metal atoms Sc, Y and La has been performed. It shows that spin density on the scandium atom represents the Sc d(yz) orbital lying in the symmetry plane of the C(2v) fullerene isomer and interacting with two carbon atoms located in the para-position on the fullerene hexagon. In contrast, the configuration of electron spin density on the heavier atoms, Y and La, is associated with the hybridized orbital formed by interaction of the metal d(yz) and p(y) electronic orbitals.

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

    Science.gov (United States)

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

    2012-11-01

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

  2. Holographic EPR Pairs, Wormholes and Radiation

    CERN Document Server

    Chernicoff, Mariano; Pedraza, Juan F

    2013-01-01

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

  3. EPR becomes reality at Finland's Olkiluoto 3

    International Nuclear Information System (INIS)

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

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

    OpenAIRE

    Ureña López, Juan

    1987-01-01

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

  5. Self-testing through EPR-steering

    Science.gov (United States)

    Šupić, Ivan; Hoban, Matty J.

    2016-07-01

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

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

    Science.gov (United States)

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

    2016-01-01

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

  7. Tetrabromidocuprates(II—Synthesis, Structure and EPR

    Directory of Open Access Journals (Sweden)

    André Zabel

    2016-04-01

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

  8. Factors influencing EPR dosimetry in fingernails

    International Nuclear Information System (INIS)

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

  9. A multifrequency EPR approach to travertine characterisation.

    Science.gov (United States)

    Di Benedetto, F; Montegrossi, G; Pardi, L A; Minissale, A; Paladini, M; Romanelli, M

    2005-11-01

    The understanding of processes that give rise to travertine deposits is important. This is so because of its widespread use as decorative material, but more so in environmental studies due to the significance, by proxy, of travertine in climatology. In this paper, a multifrequency EPR spectroscopy study of the behaviour of an ubiquitary vicariant of Ca in calcite, Mn(II), is presented. EPR spectra were obtained from a natural sample at 9.5 (X-band), 95, 190, and 285GHz, and interpreted through numerical simulation. An analysis of the distribution of the zero-field splitting interaction revealed the source of some unexpected spectral features in the width of the lines in the X-band. By contrast, the homogeneous broadening plays only a minor role. Moreover, field-dependent anisotropies of the Zeeman and hyperfine tensors were observed at higher frequency. On the basis of results garnered in this study, the ZFS interaction of Mn(II) has been ascribed to the microstructural anomalies of the Mn(II) distribution in calcite. This may be considered as the fingerprint of the physical-chemical conditions at the time of travertine deposition. As a consequence, X-band EPR spectroscopy represents a specific tool to investigate the genesis, and to check the homogeneity of Mn(II) distribution in travertines as well as in other calcite-based materials. PMID:16105744

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

    Directory of Open Access Journals (Sweden)

    Bianca Caroline Rossi-Rodrigues

    2009-06-01

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

  11. Retrospective individual dosimetry using EPR of tooth enamel

    International Nuclear Information System (INIS)

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

  12. Use of the Frank sequence in pulsed EPR.

    Science.gov (United States)

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

    2011-04-01

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

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

    International Nuclear Information System (INIS)

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

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

    International Nuclear Information System (INIS)

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2007-06-15

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

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

    Science.gov (United States)

    Nakagawa, Kouichi; Epel, Boris

    2014-10-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-10-15

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

  18. CFD modeling of the EPR primary circuit

    International Nuclear Information System (INIS)

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

  19. Instrumento para o gerenciamento de riscos ambientais

    Directory of Open Access Journals (Sweden)

    Thaiza Clemente Couto Bissacot

    2016-01-01

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

  20. Quantum Encryption Protocol Based on Continuous Variable EPR Correlations

    Institute of Scientific and Technical Information of China (English)

    HE Guang-Qiang; ZENG Gui-Hua

    2006-01-01

    A quantum encryption protocol based on Gaussian-modulated continuous variable EPR correlations is proposed. The security is guaranteed by continuous variable EPR entanglement correlations produced by nondegenerate optical parametric amplifier (NOPA). For general beam splitter eavesdropping strategy, the mutual information Ⅰ(α, ε)between Alice and Eve is calculated by employing Shannon information theory. Finally the security analysis is presented.

  1. THE RADIATION CROSSLINKING OF EPR/SBR BLEND

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wanxi; L(U) Yingtao; SUN Jiazhen

    1990-01-01

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

  2. EPR investigation of some gamma-irradiated excipients

    Science.gov (United States)

    Aleksieva, Katerina; Yordanov, Nicola D.

    2012-09-01

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

  3. Use of the Frank sequence in pulsed EPR

    DEFF Research Database (Denmark)

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

    2011-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Márcia Cristina Feres

    2008-12-01

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

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

    OpenAIRE

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

    2003-01-01

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

  6. EPR design features to mitigate severe accident challenges

    International Nuclear Information System (INIS)

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

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

    International Nuclear Information System (INIS)

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

  8. Radiation protection issues for EPR reactor

    International Nuclear Information System (INIS)

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

  9. Asymmetric EPR entanglement in continuous variable systems

    CERN Document Server

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

    2012-01-01

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

  10. EPR paradox, quantum nonlocality and physical reality

    Science.gov (United States)

    Kupczynski, M.

    2016-03-01

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

  11. FID detection of EPR and ENDOR spectra at high microwave frequencies

    Science.gov (United States)

    Blok, H.; Akimoto, I.; Milikisyants, S.; Gast, P.; Groenen, E. J. J.; Schmidt, J.

    2009-11-01

    High-frequency pulsed EPR spectroscopy allows FID detection of EPR spectra owing to the short dead time that can be achieved. This FID detection is particularly attractive for EPR and ENDOR spectroscopy of paramagnetic species that exhibit inhomogeneously broadened EPR lines and short dephasing times. Experiments are reported for the metalloprotein azurin at 275 GHz.

  12. Serum beta2-microglobulin values among healthy Brazilians using a DPC IMMULITE® assay Valores de beta2-microglobulina em brasileiros saudáveis usando o sistema automatizado DPC IMMULITE®

    Directory of Open Access Journals (Sweden)

    Fabíola Branco Filippin

    2005-02-01

    éias. MÉTODOS: Noventa e seis doadores de sangue saudáveis foram avaliados e os valores de Sb2M foram medidos por método enzima imunoensaio quimiluminescente usando analisador automatizado IMMULITE®. RESULTADOS: Os valores de Sb2M, estabelecidos por método estatístico não paramétrico, apresentaram-se entre 1.05 e 3.9 mg/ml, sendo que o limite superior obtido foi maior que o relatado em outros trabalhos. CONCLUSÃO: Este estudo apresentou novos valores, indicando que existe uma diferença significante entre os limites de referência de Sb2M disponibilizados para o IMMULITE® e os encontrados no presente trabalho, evidenciando a ocorrência de variações importantes entre diferentes populações e que novos valores devem ser considerados para brasileiros.

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

    OpenAIRE

    Nikolic, H.

    2013-01-01

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

  14. The second international intercomparison on EPR tooth dosimetry

    International Nuclear Information System (INIS)

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

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

    Directory of Open Access Journals (Sweden)

    Siderley Fernandes Albuquerque

    2011-12-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-11-01

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

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

    International Nuclear Information System (INIS)

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

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

    DEFF Research Database (Denmark)

    Simonsen, Jesper

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

  19. EPR detection of foods preserved with ionizing radiation

    Science.gov (United States)

    Stachowicz, W.; Burlinska, G.; Michalik, J.

    1998-06-01

    The applicability of the epr technique for the detection of dried vegetables, mushrooms, some spices, flavour additives and some condiments preserved with ionizing radiation is discussed. The epr signals recorded after exposure to gamma rays and to beams of 10 MeV electrons from linac are stable, intense and specific enough as compared with those observed with nonirradiated samples and could be used for the detection of irradiation. However, stability of radiation induced epr signals produced in these foods depends on storage condition. No differences in shapes (spectral parameters) and intensities of the epr spectra recorded with samples exposed to the same doses of gamma rays ( 60Co) and 10 MeV electrons were observed

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

    OpenAIRE

    Hurtado Cortés, Luini Leonardo

    2013-01-01

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

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

    Indian Academy of Sciences (India)

    2016-07-01

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

  2. Lorentz symmetry breaking effects on relativistic EPR correlations

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-09-15

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

  3. EPR Hidden Medical Image Secret Sharing using DNA Cryptography

    OpenAIRE

    L.Jani Anbarasi; Dr.G.S.Anandha Mala

    2014-01-01

    Security of medical images is an important issue, since applications such as Tele diagnosis exchange information over insecure communication channels. In this paper, Shamir secret sharing algorithm combined with DNA cryptography is proposed. The method involves the dispersion of medical image and Electronic Patient Record (EPR) into shadow images, aiming at better security characteristics. The EPR is hidden into the medical image using DNA hiding techniques. Huffman encoding is used to compre...

  4. Study of metalloproteins using continuous wave electron paramagnetic resonance (EPR).

    Science.gov (United States)

    Gambarelli, Serge; Maurel, Vincent

    2014-01-01

    Electron paramagnetic resonance (EPR) is an invaluable tool when studying systems with paramagnetic centers. It is a sensitive spectroscopic method, which can be used with dilute samples in aqueous buffer solutions. Here, we describe the basic procedure for recording an X-band EPR spectrum of a metalloprotein sample at low temperature. We also discuss basic optimization techniques to provide spectra with a high signal to noise ratio and minimum distortion.

  5. EPC projects for EPR Flamanville 3 NPP

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-07-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-06-15

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

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

    Science.gov (United States)

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

    2011-06-01

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

  8. Sistema automatizado para la calibración de acelerómetros según norma ISO 16063-21:2003

    OpenAIRE

    Ruiz Montalvo, Alex

    2010-01-01

    La dura competitividad del sector de automoción hace que la acreditación de los laboratorios de ensayo sea cada vez más frecuente en este sector. El cliente se siente más tranquilo cuando tiene una garantía de que el trabajo que realiza la empresa ha sido acreditado por una entidad nacional como ENAC. Debido a recientes acreditaciones en ensayos de seguridad pasiva y al crecimiento del número de acelerómetros en los laboratorios de instrumentación, se hace imprescindib...

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

    OpenAIRE

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

    2007-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-07-01

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

  11. Sistemas automatizados: discussões acerca de seus benefícios para as unidades de informação

    Directory of Open Access Journals (Sweden)

    Cirlene Maciel de Oliveira Melo

    2014-04-01

    Full Text Available Trata da importância da implantação de um sistema de automação nas bibliotecas. Mostra a praticidade e segurança encontrada pelo profissional da informação em trabalhar com a catalogação automatizada em contraste com a catalogação manual. Expõe a necessidade dos softwares serem compatíveis com os padrões e protocolos da catalogação cooperativa internacional. Demonstra a facilidade e o tempo economizados pelo catalogador quando o mesmo utiliza a cooperação de dados através de instituições que os disponibilizam na rede ou bibliotecas que permitem a importação de seus dados. Apresenta as facilidades encontradas pelos usuários na busca e recuperação da informação por meio dos catálogos on-line. Discorre sobre os principais serviços remotos oferecidos aos clientes das instituições através dos catálogos. Disserta a variedade de acervos virtuais que permitem o acesso de diversos tipos de documentos pelos usuários das bibliotecas.

  12. El OPAC con valor añadido: 4o utilidades para los usuarios de los catálogos automatizados

    OpenAIRE

    Sánchez Herrador, Miguel Ángel; Boza Puerta, Mariano; Márquez Muñoz, Antonio T.

    2005-01-01

    Since the appearance of the site was that the defendant OPAC fits-all innovations that have emerged. These demands have ranged from the interface to the provision of scanned documents or greater interaction with the user. In this paper we analyze the present and future profits, and suggests a classification of the same. It also explores his relationship with the portal-site of the library, as well as statutory limitations for the development of services.

  13. Pulsed EPR for studying silver clusters

    Energy Technology Data Exchange (ETDEWEB)

    Michalik, J.; Wasowicz, T.; Sadlo, J. [Institute of Nuclear Chemistry and Technology, Warsaw (Poland); Reijerse, E.J. [Katholieke Univ., Nijmegen (Netherlands). Dept. of Molecular Spectroscopy; Kevan, L. [Texas Univ., Houston, TX (United States). Dept. of Chemistry

    1996-01-01

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

  14. Pulsed EPR for studying silver clusters

    Science.gov (United States)

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

    1996-01-01

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

  15. Arbitrated Quantum Signature protocol using EPR pairs

    Directory of Open Access Journals (Sweden)

    Jun Zhang

    2012-11-01

    Full Text Available Arbitrated signature provides that the signatory signs a message with his private key by quantum cryptography, while the signature receiver verifies the signature with the arbitrator’s assistance. In this work, security analysis was given to the arbitrated quantum signature (AQS and results showed that the receiver Bob and the attacker can forge the signature. Then this paper gives a new quantum one-time pads encryption method, which is suit for the quantum signature. At last, a new AQS protocol using Einstein-Podoisky-Rosen (EPR pairs is proposed. By using of  quantum key distribution (QKD and new quantum one-time pads, the new scheme can resist Shor’s attack. The new scheme has following advantages: (1 The scheme reduces the complexity of implementation and provides a higher efficiency in transmission; (2 Compares with some AQS schemes, the scheme can avoid being disavowed by the receiver; (3 Compares with other AQS schemes, the scheme also guarantees the arbitrator cannot forge the signature and it also ensure the receiver and other attacker cannot forge the signature.

  16. Asymmetric EPR entanglement in continuous variable systems

    International Nuclear Information System (INIS)

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

  17. EPR by Areva. The path of greatest certainty

    International Nuclear Information System (INIS)

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Haskell, E.H.

    1996-12-31

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

  19. EPR/Homotaurine: A possible dosimetry system for high doses

    Energy Technology Data Exchange (ETDEWEB)

    Maghraby, A., E-mail: maghrabism@yahoo.com [National Institute of Standards (NIS) - Radiation Dosimetry Department - Tersa st. 12211 Giza, P.O. Box 136 (Egypt); Salama, E. [Physics Department, Faculty of Science, Ain Shams University, 11566 Cairo (Egypt); Mansour, A. [National Center for Radiation Research and Technology, Atomic Energy Authority, Nasr City, Cairo (Egypt)

    2011-12-11

    An EPR investigation of radiation induced radicals in Homotaurine revealed that there are two types of radicals produced after exposure to gamma radiation ({sup 60}Co). EPR spectra were recorded and analyzed; also the microwave power saturation curves for both radicals were studied. The effect of change in modulation amplitude on peak-to-peak signal height and line width was investigated; this is in addition to the evaluation of energy dependence parameters compared to soft tissue and alanine dosimeters. Response of Homotaurine to different radiation doses (0.5 kGy-50 kGy) was studied and found to follow a linear relationship. Radiation induced radicals in Homotaurine persisted and showed a noticeable stability over 30 days following irradiation. It was found that Homotaurine possesses good dosimetric properties using EPR spectroscopy in high doses and is characterized by its simple spectrum.

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

    CERN Document Server

    Susskind, Leonard

    2014-01-01

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

  1. Identification and dosimetry of irradiated walnuts (Juglans regia) using EPR

    Science.gov (United States)

    Maghraby, A.; Salama, E.; Sami, A.; Mansour, A.; El-Sayed, M.

    2012-03-01

    Electron paramagnetic resonance (EPR) is an easy, fast, and reliable tool for identification of irradiated food. Untreated nuts may encounter hazards of carrying several pathogens or microbial contamination; walnuts are of specific importance due to their nutritional and medicinal values, and hence walnut processing via gamma irradiation is a necessary step. EPR was employed for the identification and dosimetry of Cs-137 gamma-irradiated walnuts (shells and kernels). Several important parameters were studied, such as spectral features, microwave power dependence of signal intensities, and short- and long-term time dependences. Responses of walnut shells and kernels to different radiation doses in the range 0-10 kGy were investigated. Results confirmed that EPR is a suitable tool for the identification and dosimetry of irradiated walnuts using either their shells or only kernels.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-01-15

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

  3. Which Parts of a Clinical Process EPR Needs Special Configuration

    DEFF Research Database (Denmark)

    Barlach, Anders; Simonsen, Jesper

    2007-01-01

    Subject: Which parts of an electronic patient record (EPR) can initially form a stable standard solution to be used by all clinicians? And which parts of an EPR can we predict needs initial as well as on-going re-configuration to meet the needs from diverse medical specialties. Purpose: To analyze...... which screen types in a clinical process that can be standard configured and which are subject to initial as well as on-going re-configuration. Methods and results: A pilot-project implementing a fully functional clinical process EPR was configured and used at a neurological ward, replacing all paper...... to several re-configurations and they stabilize after an average of six iterations: Some may further stabilize over time since they address new but also general ways of working. Other screens relates to the specific medical specialty and cannot be part of a standard solution....

  4. A new causal interpretation of EPR-B experiment

    Science.gov (United States)

    Gondran, Michel; Gondran, Alexandre

    2012-12-01

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

  5. EPR studies of gamma-irradiated taurine single crystals

    Energy Technology Data Exchange (ETDEWEB)

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

    2000-04-01

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

  6. EPR studies of gamma-irradiated taurine single crystals

    Science.gov (United States)

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

    2000-04-01

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

  7. Nuclear choice. Towards the EPR with mincing steps

    International Nuclear Information System (INIS)

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

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

    CERN Document Server

    Muchowski, Eugen

    2016-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-08-15

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

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

    OpenAIRE

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

    2013-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Jemain, A

    2003-10-01

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

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

    OpenAIRE

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

    1999-01-01

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

  13. Security of EPR-based Quantum Key Distribution

    CERN Document Server

    Inamori, H

    2000-01-01

    We propose a proof of the security of EPR-based quantum key distribution against enemies with unlimited computational power. The proof holds for a protocol using interactive error-reconciliation scheme. We assume in this paper that the legitimate parties receive a given number of single photon signals and that their measurement devices are perfect.

  14. Non-local common cause explanations for EPR

    CERN Document Server

    Egg, Matthias

    2013-01-01

    The paper argues that a causal explanation of the correlated outcomes of EPR-type experiments is desirable and possible. It shows how Bohmian mechanics and the GRW mass density theory offer such an explanation in terms of a non-local common cause.

  15. Nonlinear Simulation of the Tooth Enamel Spectrum for EPR Dosimetry

    Science.gov (United States)

    Kirillov, V. A.; Dubovsky, S. V.

    2016-07-01

    Software was developed where initial EPR spectra of tooth enamel were deconvoluted based on nonlinear simulation, line shapes and signal amplitudes in the model initial spectrum were calculated, the regression coefficient was evaluated, and individual spectra were summed. Software validation demonstrated that doses calculated using it agreed excellently with the applied radiation doses and the doses reconstructed by the method of additive doses.

  16. EPR Hidden Medical Image Secret Sharing using DNA Cryptography

    Directory of Open Access Journals (Sweden)

    L.Jani Anbarasi

    2014-07-01

    Full Text Available Security of medical images is an important issue, since applications such as Tele diagnosis exchange information over insecure communication channels. In this paper, Shamir secret sharing algorithm combined with DNA cryptography is proposed. The method involves the dispersion of medical image and Electronic Patient Record (EPR into shadow images, aiming at better security characteristics. The EPR is hidden into the medical image using DNA hiding techniques. Huffman encoding is used to compress the DNA encoded secret image, which is then securely shared into shadow images using Shamir secret sharing. Then, the shadows are embedded into a host image using steganographic technique with modular operation. During reconstruction, at least t shadows are pooled to reconstruct the compressed secret image, which is again decoded using Huffman decoding to reveal the DNA encoded secret image. The medical image and EPR are separated using the reverse technique of DNA hiding. The simulation results and the security analysis prove that this method can hide longer EPR strings along with better confidentiality and authenticity. Better PSNR is achieved and the correlation co-efficient shows that this also has the ability of resisting various attacks.

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

    CERN Document Server

    Susskind, Leonard

    2016-01-01

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

  18. A fast method for ionized food identification: EPR

    International Nuclear Information System (INIS)

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

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

    International Nuclear Information System (INIS)

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

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

    International Nuclear Information System (INIS)

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-09-15

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-08-15

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

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

    International Nuclear Information System (INIS)

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

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

    Directory of Open Access Journals (Sweden)

    Fernando Toledano Cuervas-Mons

    2015-01-01

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

  5. EPR becomes reality at Finland's Olkiluoto 3

    Energy Technology Data Exchange (ETDEWEB)

    Gueldner, R.; Giese, U

    2005-07-01

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

  6. A new EPR dosimeter based on sulfanilic acid

    Energy Technology Data Exchange (ETDEWEB)

    Maghraby, A. [Radiation Dosimetry Department, National Institute for Standards (NIS), Ministry of Scientific Research, Haram, Giza, Tersa Street, P.O. Box 136 (Egypt)]. E-mail: maghrabism@yahoo.com; Tarek, E. [Physics Department, Faculty of Science, Fayoum University, Fayoum (Egypt)

    2006-02-15

    A new radiation dosimeter based on sulfanilic acid was suggested and tested. Radiation-induced radical EPR spectrum was recorded and characterized. EPR spectrum of sulfanilic acid is characterized by its simple single signal, which is located at g-factor=2.0053+/-0.00017. Its microwave absorption curve and effect of modulation amplitude on signal intensity and line width were studied. The radiation-induced radical was found to be stable after about 24h following irradiation within +/-1.2%. Energy dependence curves of sulfanilic acid compared to soft tissue and alanine were plotted. Sulfanilic acid is characterized also by its isotropic behavior and its calibration curve in {sup 137}Cs gamma radiation is plotted compared to that of alanine. Its sensitivity is about 85% of alanine, while its detection limit is about 100+/-30mGy.

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

    Energy Technology Data Exchange (ETDEWEB)

    Gualtieri, G. E-mail: gianni@fismedw2.univaq.it; Colacicchi, S.; Sgattoni, R.; Giannoni, M

    2001-07-01

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

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

    Science.gov (United States)

    Herrling, Thomas; Fuchs, Jürgen; Groth, Norbert

    2002-01-01

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

  9. EPR of divalent manganese in non-Kramers hosts

    International Nuclear Information System (INIS)

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

  10. Total loss of AC power analysis for EPR reactor

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-08-15

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

  11. Kinetic measurements using EPR imaging with a modulated field gradient.

    Science.gov (United States)

    Herrling, Thomas; Fuchs, Jürgen; Groth, Norbert

    2002-01-01

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

  12. EPR study of spermine interaction with multilamellar phosphatidylcholine liposomes.

    Science.gov (United States)

    Momo, F; Wisniewska, A; Stevanato, R

    1995-11-22

    The interaction of spermine with egg-yolk phosphatidylcholine liposomes was investigated. The EPR spin labeling technique evidenced that spermine induces modifications of some membrane functions of biological interest like water permeability and is a possible modulator of diffusion processes for charged and polar molecules. The association constant for a hypothesized complex between spermine and the phosphate group of phosphatidylcholine was evaluated by enzymatic methods.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-07-30

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

  14. Copenhagen vs Everett, teleportation, and ER=EPR

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-06-15

    Quantum gravity may have as much to tell us about the foundations and interpretation of quantum mechanics as it does about gravity. The Copenhagen interpretation of quantum mechanics and Everett's Relative State Formulation are complementary descriptions which in a sense are dual to one another. My purpose here is to discuss this duality in the light of the of ER=EPR conjecture. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

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

    International Nuclear Information System (INIS)

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

  16. An Introduction to the Epr-Chameleon Experiment

    Science.gov (United States)

    Accardi, Luigi; Imafuku, Kentaro; Regoli, Massimo

    2003-02-01

    On September 27 (2001), as a side activity to the "Japan-Italy Joint workshop on: Quantum open systems and quantum measurement", the first public demonstration of the dynamical EPR-chameleon experiment was performed at Waseda University in order to give an experimental answer to a long standing question in the foundations of quantum theory: do there exist classical macroscopic systems which, by local independent choices, produce sequences of data which reproduce the singlet correlations, hence violating Bell's inequality? The EPR-chameleon experiment gives an affirmative answer to this question by concretely producing an example of such systems in the form of three personal computers which realize a local deterministic dynamical evolution whose mathematical structure is very simple and transparent. In the experiment performed on September 27 the local dynamics used was not a reversible one because the interaction with the degrees of freedom of the apparatus was integrated out giving rise to an effective Markovian dynamics which, although mapping probability measures into probability measures, did not preserve the ±1-values of the spin (or polarization) observables. This feature was criticized by some of the partecipants and the following two questions arose: i) is it possible to prove that the Markovian evolution, used in the experiment, is indeed the reduced evolution of a bona fide reversible evolution? ii) if the answer to question (i) is affirmative, is it possible to reproduce the EPR correlations by simply considering empirical averages of ±1-values, as one does in usual EPR type experiments? An affirmative answer to these questions was given in the paper [AcImRe01] and it is briefly reviewed in what follows.

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

    OpenAIRE

    William Bertoloni; Douglas Andreolla

    2010-01-01

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

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

    International Nuclear Information System (INIS)

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

  19. Peptide-membrane Interactions by Spin-labeling EPR

    Science.gov (United States)

    Smirnova, Tatyana I.; Smirnov, Alex I.

    2016-01-01

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

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

    Science.gov (United States)

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

    2016-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Peter Strauch

    2012-02-01

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

  2. EPR investigation of some traditional oriental irradiated spices

    Science.gov (United States)

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

    2007-06-01

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

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

    Science.gov (United States)

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

    2010-04-01

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

  4. EPR investigation of some traditional oriental irradiated spices

    Energy Technology Data Exchange (ETDEWEB)

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

    2007-06-15

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1993-06-01

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

  6. EPR, optical, infrared and Raman spectral studies of Actinolite mineral.

    Science.gov (United States)

    Gopal, N O; Narasimhulu, K V; Rao, J L

    2004-09-01

    Electron paramagnetic resonance (EPR), optical, infrared and Raman spectral studies have been performed on a natural Actinolite mineral. The room temperature EPR spectrum reveals the presence of Mn(2+) and Fe(3+) ions giving rise to two resonance signals at g = 2.0 and 4.3, respectively. The resonance signal at g = 2.0 exhibits a six line hyperfine structure characteristic of Mn(2+) ions. EPR spectra have been studied at different temperatures from 123 to 433 K. The number of spins (N) participating in the resonance at g = 2.0 has been calculated at different temperatures. A linear relationship is observed between log N and 1/T in accordance with Boltzmann law and the activation energy was calculated. The paramagnetic susceptibility (chi) has been calculated at different temperatures and is found to be increasing with decreasing temperature as expected from Curie's law. From the graph of 1/chi versus T, the Curie constant and Curie temperature have been evaluated. The optical absorption spectrum exhibits bands characteristic of Fe(2+) and Fe(3+) ions. The crystal field parameter Dq and the Racah parameters B and C have been evaluated from the optical absorption spectrum. The infrared spectral studies reveal the formation of Fe(3+)--OH complexes due to the presence of higher amount of iron in this mineral. The Raman spectrum exhibits bands characteristic of Si--O--Si stretching and Mg?OH translation modes. PMID:15294226

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

    CERN Document Server

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

    2000-01-01

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

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

    Institute of Scientific and Technical Information of China (English)

    景军涛; 江才林; 罗吾希; 郑晨

    2013-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

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

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

    International Nuclear Information System (INIS)

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

  11. In Vivo Imaging of Tissue Physiological Function using EPR Spectroscopy | NCI Technology Transfer Center | TTC

    Science.gov (United States)

    Electron paramagnetic resonance (EPR) is a technique for studying chemical species that have one or more unpaired electrons.  The current invention describes Echo-based Single Point Imaging (ESPI), a novel EPR image formation strategy that allows in vivo imaging of physiological function.  The National Cancer Institute's Radiation Biology Branch is seeking statements of capability or interest from parties interested in in-licensing an in vivo imaging using Electron paramagnetic resonance (EPR) to measure active oxygen species.

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

    Directory of Open Access Journals (Sweden)

    F. J. Moreno

    2010-09-01

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

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

    DEFF Research Database (Denmark)

    Simonsen, Jesper; Hertzum, Morten

    2006-01-01

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

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

    International Nuclear Information System (INIS)

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

  15. EPR meets the next generation PWR safety requirements

    International Nuclear Information System (INIS)

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

  16. Biossensor para deteção do antigénio específico da próstata

    OpenAIRE

    Oliveira, Nélia Maria Pinto de

    2011-01-01

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

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

    International Nuclear Information System (INIS)

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Troup, G.J.; Hutton, D.R. [Monash Univ., Clayton, VIC (Australia). Dept. of Physics; Bacci, M.; Lotti, F.; Casini, A.; Picollo, M. [Istituto di Ricerca sulle Onde Elettromagnetiche, Florence, Italy (Italy)

    1996-12-31

    Full text: Visible and near-infra-red reflectance spectroscopy are now routinely used for the identification of paint pigments in Renaissance painting, thus playing a part in authentication and restoration. Since most of the pigments are minerals, and many minerals either contain traces of paramagnetic ions, or have paramagnetic ions in their main components (e.g., chromic oxide, haematite), it seemed logical to determine whether EPR could distinguish between different pigments. 14 pigments of different colours were tested in a Varian E-12 EPR spectrometer, at a frequency of {approx} 9.1 GHz. Measurements were made at room ({approx} 20 deg C) and liquid N{sub 2} temperatures, in the standard special quartz sample tubes. The active volume is 0. 15 ml, but at most, a volume of sample (powder) one tenth of this was used. The spectra (to be shown) clearly demonstrate that EPR can distinguish between different pigments. The power was 1 milliwatt, the modulation amplitude 4 gauss, the total field sweep 10,000 gauss, centred 5000 gauss and the amplification between 10{sup 2} and 10{sup 4}, as indicated on the charts. The signal to noise ratio is excellent, and sensitivity could be increased (if necessary) by a factor of {approx} 10{sup 3}, thus allowing much smaller samples to be tested. Because the signals are so strong it should be possible to scan at least small painted canvases by the following non-destructive technique, using existing equipment. All that is required is a modified resonant cavity; it must have a high Q, and a slot where the magnetic field is maximum, and the electric field zero. The canvas can thus be placed flush with the waveguide, to interact with the microwave magnetic field emanating from the slot

  19. EPR-a blend of national design types

    International Nuclear Information System (INIS)

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

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

    International Nuclear Information System (INIS)

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-02-15

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

  2. Mn distribution in natural sphalerites: a micronalytical and EPR study

    Science.gov (United States)

    di Benedetto, F.; Bernardini, G. P.; Cipriani, C.; Plant, D.; Romanelli, M.; Vaughan, D. J.

    2003-04-01

    Electron Paramagnetic Resonance (EPR) has been successfully applied to determine the local coordination and distribution of transition metal cations in sulphides and sulphosalts (Di Benedetto et al., 2002). Due to its enhanced sensitivity and element-specificity it is one of the best tools to monitor Mn(II) behaviour down to very low concentrations. In order to reach a fuller understanding of the spectroscopic results, a microanalytical study has also been undertaken by means of Electron Microprobe Analysis. Operating conditions were chosen to achieve the lowest possible detection limits, taking into account that Mn can replace Zn in the sphalerite lattice both as a minor and trace element, and that EPR can detect Mn(II) below the ppm range. Six natural samples from the Museo di Storia Naturale, Università di Firenze, were selected to have pure single crystals and avoid magnetically active phases associated with the sphalerite. The Mn concentration determined ranges between 30 and 14300 ppm and Mn content varies considerably within the same sample, leading to differences up to the 50% as compared to the mean value. X-ray images confirm Mn to be distributed with an unusual pattern, unrelated to the other common Zn-replacing cations, Fe and Cd, present in the samples. Powder EPR spectra reveal at least three different Mn(II) signals: two sextets, overlapping in all samples containing Mn as trace element, and a single line, present only in the more concentrated samples. While the latter have been attributed to an inhomogeneous Mn distribution, due to an enhanced Mn-Mn superexchange interaction, the difference between the two sextets, observed by means of EEPR investigations in a synthetic sphalerite (Di Benedetto et al., 2002), appears unrelated to the Mn concentration and may be attributed to small differences in the local coordination of Mn(II) ions. This, in turn, may be explained by the segregation of small amounts of Mn into polytypic domains, features which

  3. EPR spectra of four gadolinium complexes with Schiff bases

    Institute of Scientific and Technical Information of China (English)

    姚克敏; 陈德余; 封子先; 李冬成; 冯亚菲; 何玲

    1995-01-01

    EPR spectra of four new gadolinium complexes with Schiff bases in polycrystalline powder and those of these complexes in three organic solvents were investigated at different temperatures. It has been observed for the first time that their freezing solution spectra are quite different from each other. In THF one peak was observed only, but there were three peaks and typical "U" spectral features appearing in DMF and DMSO at low temperatures. On the basis of spin Hamiltonian of S = 7/2 system, the correlations between crystal field strength in complexes and local symmetry around Gd3+ ions are discussed.

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

    International Nuclear Information System (INIS)

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

  5. Structured Reporting Method for ePR Generation

    OpenAIRE

    Arash Ebrahimi

    2007-01-01

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

  6. Medical reference dosimetry using EPR measurements of alanine

    DEFF Research Database (Denmark)

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

    2009-01-01

    Background. Electron spin resonance (EPR) is used to determine the absorbed dose of alanine dosimeters exposed to clinical photon beams in a solid-water phantom. Alanine is potentially suitable for medical reference dosimetry, because of its near water equivalence over a wide energy spectrum, low...... methods the proposed algorithm can be applied without normalisation of phase shifts caused by changes in the g-value of the cavity. The study shows that alanine dosimetry is a suitable candidate for medical reference dosimetry especially for quality control applications....

  7. An EPR Experiment for the Undergraduate Physical Chemistry Laboratory

    Science.gov (United States)

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

    2000-11-01

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

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

    Science.gov (United States)

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

    1999-01-01

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

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

    International Nuclear Information System (INIS)

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

  10. N-player quantum games in an EPR setting

    CERN Document Server

    Chappell, James M; Abbott, Derek

    2012-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1993-01-01

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

  12. EPR dosimetry of glass substrate of mobile phone LCDs

    International Nuclear Information System (INIS)

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

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

    International Nuclear Information System (INIS)

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

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

    International Nuclear Information System (INIS)

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

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

    International Nuclear Information System (INIS)

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

  16. New Developments in Spin Labels for Pulsed Dipolar EPR

    Directory of Open Access Journals (Sweden)

    Alistair J. Fielding

    2014-10-01

    Full Text Available Spin labelling is a chemical technique that enables the integration of a molecule containing an unpaired electron into another framework for study. Given the need to understand the structure, dynamics, and conformational changes of biomacromolecules, spin labelling provides a relatively non-intrusive technique and has certain advantages over X-ray crystallography; which requires high quality crystals. The technique relies on the design of binding probes that target a functional group, for example, the thiol group of a cysteine residue within a protein. The unpaired electron is typically supplied through a nitroxide radical and sterically shielded to preserve stability. Pulsed electron paramagnetic resonance (EPR techniques allow small magnetic couplings to be measured (e.g., <50 MHz providing information on single label probes or the dipolar coupling between multiple labels. In particular, distances between spin labels pairs can be derived which has led to many protein/enzymes and nucleotides being studied. Here, we summarise recent examples of spin labels used for pulse EPR that serve to illustrate the contribution of chemistry to advancing discoveries in this field.

  17. Cd 2+ effect on free radicals in Cladosporium cladosporioides-melanin tested by EPR spectroscopy

    Science.gov (United States)

    Matuszczyk, Magdalena; Buszman, Ewa; Pilawa, Barbara; Witoszyńska, Teresa; Wilczok, Tadeusz

    2004-08-01

    Changes in free radicals system of Cladosporium cladosporioides-melanin and model DOPA-melanin caused by diamagnetic Cd 2+ ions were studied by electron paramagnetic resonance (EPR) spectroscopy. EPR line of eumelanin was mainly found in the spectrum of Cl.cl.-melanin. Cd 2+ ions increased o-semiquinone free radicals concentration in both natural and synthetic melanins. Cd 2+ broadened EPR lines of Cl.cl.-melanin in mycelium and the ions fastened spin-lattice relaxation processes. The narrower EPR lines and slower spin-lattice relaxation were obtained for DOPA-melanin-Cd 2+ complexes than for DOPA-melanin. Pheomelanin additionally existing in Cl.cl. samples was responsible for differences between the EPR data for Cl.cl. melanin and DOPA-melanin.

  18. Alcoholic extraction enables EPR analysis to characterize radiation-induced cellulosic signals in spices.

    Science.gov (United States)

    Ahn, Jae-Jun; Sanyal, Bhaskar; Akram, Kashif; Kwon, Joong-Ho

    2014-11-19

    Different spices such as turmeric, oregano, and cinnamon were γ-irradiated at 1 and 10 kGy. The electron paramagnetic resonance (EPR) spectra of the nonirradiated samples were characterized by a single central signal (g = 2.006), the intensity of which was significantly enhanced upon irradiation. The EPR spectra of the irradiated spice samples were characterized by an additional triplet signal at g = 2.006 with a hyperfine coupling constant of 3 mT, associated with the cellulose radical. EPR analysis on various sample pretreatments in the irradiated spice samples demonstrated that the spectral features of the cellulose radical varied on the basis of the pretreatment protocol. Alcoholic extraction pretreatment produced considerable improvements of the EPR signals of the irradiated spice samples relative to the conventional oven and freeze-drying techniques. The alcoholic extraction process is therefore proposed as the most suitable sample pretreatment for unambiguous detection of irradiated spices by EPR spectroscopy.

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

    International Nuclear Information System (INIS)

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

  20. Control de gestión para procesos de apoyo hoteleros

    Directory of Open Access Journals (Sweden)

    María Alejandra Ferrer

    2004-01-01

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

  1. Erection progress of OL3 and other EPR projects

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-07-01

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

  2. Erection progress of OL3 and other EPR projects

    International Nuclear Information System (INIS)

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

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

    OpenAIRE

    Miranda, Fabiani das Dores Abati

    2013-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2002-10-01

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

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

    International Nuclear Information System (INIS)

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

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

    Directory of Open Access Journals (Sweden)

    Adamczyk Jakub

    2015-07-01

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

  7. Active cancellation - A means to zero dead-time pulse EPR

    Science.gov (United States)

    Franck, John M.; Barnes, Ryan P.; Keller, Timothy J.; Kaufmann, Thomas; Han, Songi

    2015-12-01

    The necessary resonator employed in pulse electron paramagnetic resonance (EPR) rings after the excitation pulse and creates a finite detector dead-time that ultimately prevents the detection of signal from fast relaxing spin systems, hindering the application of pulse EPR to room temperature measurements of interesting chemical or biological systems. We employ a recently available high bandwidth arbitrary waveform generator (AWG) to produce a cancellation pulse that precisely destructively interferes with the resonant cavity ring-down. We find that we can faithfully detect EPR signal at all times immediately after, as well as during, the excitation pulse. This is a proof of concept study showcasing the capability of AWG pulses to precisely cancel out the resonator ring-down, and allow for the detection of EPR signal during the pulse itself, as well as the dead-time of the resonator. However, the applicability of this approach to conventional EPR experiments is not immediate, as it hinges on either (1) the availability of low-noise microwave sources and amplifiers to produce the necessary power for pulse EPR experiment or (2) the availability of very high conversion factor micro coil resonators that allow for pulse EPR experiments at modest microwave power.

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

    CERN Document Server

    Seki, Shigenori

    2014-01-01

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

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

    International Nuclear Information System (INIS)

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

  10. EPR dosimetry with synthetic A-type carbonated apatite

    International Nuclear Information System (INIS)

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

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

    International Nuclear Information System (INIS)

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

  12. Effect of irradiation on chemiluminescence of EPR pure valcanisate

    International Nuclear Information System (INIS)

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

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

    Directory of Open Access Journals (Sweden)

    James M Chappell

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

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

    International Nuclear Information System (INIS)

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

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

    International Nuclear Information System (INIS)

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-12-15

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

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

    Science.gov (United States)

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

    2010-12-01

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

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

    Science.gov (United States)

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

    2008-12-01

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

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

    DEFF Research Database (Denmark)

    Koksharov, Y.A.; Bykov, I.V.; Malakho, A.P.;

    2002-01-01

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

  20. EPR statistical mixture of correlated states with fractional brownian process induced by third party interaction

    CERN Document Server

    Tamburini, F; Bianchini, A

    1999-01-01

    A time-correlated EPR pairs protocol is analized, based on detection of fractal correlated signals into a statistical mixture of EPR correlated pairs: an approximated alpha-Fractional Brownian Motion (FBM) is induced on the group of EPR pairs (e.g. by sender-third party eavesdropper-like interactions as in Ekert quantum cryptography), to be detected by the receiver using a non - orthogonal wavelet filter, able to characterize the FBM from a noisy enviroment by formalizing a nonlinear optimization problem for the FBM alpha-characteristic parameter extimation.

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

    International Nuclear Information System (INIS)

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

  2. Aditivos para concretos de projeção

    Directory of Open Access Journals (Sweden)

    Pileggi R. G.

    2002-01-01

    Full Text Available A crescente utilização de procedimentos automatizados para a instalação de concretos refratários, como bombeamento e projeção, deve-se ao entendimento simultâneo das solicitações de cada técnica de instalação e dos fatores que determinam a natureza reológica destes materiais. No caso dos concretos de projeção, importante ainda é avaliar a ação dos aditivos (floculantes, aceleradores de pega, etc. normalmente utilizados para auxiliar a consolidação e adesão do material na superfície aplicada, reduzindo o desperdício (rebote durante a aplicação. Contudo, os procedimentos convencionais de análise, baseados em ensaios de consistência ou em análises pós-cura, não permitem simular a influência dos aditivos na projeção do material. Neste trabalho, foi desenvolvida uma nova técnica experimental baseada na reometria de concretos, a qual foi utilizada na análise de aditivos comerciais, além de outros que teoricamente possuem potencial para auxiliar a consolidação da aplicação de concretos por projeção. Os resultados comprovaram a eficácia da técnica de ensaio desenvolvida e possibilitaram a identificação de novos aditivos que elevam a eficiência da projeção.

  3. Sequential CW-EPR image acquisition with 760-MHz surface coil array.

    Science.gov (United States)

    Enomoto, Ayano; Hirata, Hiroshi

    2011-04-01

    This paper describes the development of a surface coil array that consists of two inductively coupled surface-coil resonators, for use in continuous-wave electron paramagnetic resonance (CW-EPR) imaging at 760 MHz. To make sequential EPR image acquisition possible, we decoupled the surface coils using PIN-diode switches, to enable the shifting of the resonators resonance frequency by more than 200 MHz. To assess the effectiveness of the surface coil array in CW-EPR imaging, two-dimensional images of a solution of nitroxyl radicals were measured with the developed coil array. Compared to equivalent single coil acquired images, we found the visualized area to be extended approximately 2-fold when using the surface coil array. The ability to visualize larger regions of interest through the use of a surface coil array, may offer great potential in future EPR imaging studies. PMID:21320789

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

    Science.gov (United States)

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

    2016-08-26

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

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

    Science.gov (United States)

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

    2005-09-01

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

  6. A view of EPR non-locality problems based on Aron's stochastic foundation of relativity

    Science.gov (United States)

    Scheer, Jens

    1990-12-01

    It is argued that the problem of causal anomalies that still may exist in Vigier's explanation of superluminal EPR type correlations may be removed in the framework of Aron's stochastic foundation of relativity.

  7. Irradiation for dating Brazilian fish fossil by thermoluminescence and EPR technique

    Energy Technology Data Exchange (ETDEWEB)

    Sullasi, H.S.; Andrade, M.B.; Ayta, W.E.F.; Frade, M.; Sastry, M.D.; Watanabe, S

    2004-01-01

    Fish fossil from Ceara State, Brazil has been investigated using thermoluminescence and EPR method. In both cases, additive method has been used by irradiating fossil samples to very high doses (tens of kGy). In the case of thermoluminescence, 360 deg. C peak was used for dating. Since the fish fossil contains relatively high concentration of Mn, the EPR Mn{sup 2+}-lines cover carbonate and sulfate radicals signal (sulfur is also present in large amount), therefore 50 mW microwave power was used for EPR measurements. At this high power region Mn{sup 2+}-lines become very little intense and SO{sub 2}{sup -} and CO{sub 2}{sup -} can be detected. Both TL and EPR dating presented an age around 8 Ma. Correction due to spontaneous decay of 360 deg. C peak at ambient temperature gives rise to about {approx}24 Ma of age.

  8. The strength of EPR and ENDOR techniques in revealing structure-function relationships in metalloproteins.

    Science.gov (United States)

    Van Doorslaer, Sabine; Vinck, Evi

    2007-09-01

    Recent technological and methodological advances have strongly increased the potential of electron paramagnetic resonance (EPR) and electron nuclear double resonance (ENDOR) techniques to characterize the structure and dynamics of metalloproteins. These developments include the introduction of powerful pulsed EPR/ENDOR methodologies and the development of spectrometers operating at very high microwave frequencies and high magnetic fields. This overview focuses on how valuable information about metalloprotein structure-function relations can be obtained using a combination of EPR and ENDOR techniques. After an overview of the historical development and a limited theoretical description of some of the key EPR and ENDOR techniques, their potential will be highlighted using selected examples of applications to iron-, nickel-, cobalt-, and copper-containing proteins. We will end with an outlook of future developments.

  9. EPR spectroscopy of protein microcrystals oriented in a liquid crystalline polymer medium

    Science.gov (United States)

    Caldeira, Jorge; Figueirinhas, João Luis; Santos, Celina; Godinho, Maria Helena

    2004-10-01

    Correlation of the g-tensor of a paramagnetic active center of a protein with its structure provides a unique experimental information on the electronic structure of the metal site. To address this problem, we made solid films containing metalloprotein ( Desulfovibrio gigas cytochrome c3) microcrystals. The microcrystals in a liquid crystalline polymer medium (water/hydroxypropylcellulose) were partially aligned by a shear flow. A strong orientation effect of the metalloprotein was observed by EPR spectroscopy and polarizing optical microscopy. The EPR spectra of partially oriented samples were simulated, allowing for molecular orientation distribution function determination. The observed effect results in enhanced sensitivity and resolution of the EPR spectra and provides a new approach towards the correlation of spectroscopic data, obtained by EPR or some other technique, with the three-dimensional structure of a protein or a model compound.

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

    Science.gov (United States)

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

    2015-11-01

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

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

    CERN Document Server

    Bao, Ning; Remmen, Grant N

    2015-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-06-15

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

  13. Application of electron paramagnetic resonance (EPR) spectroscopy and imaging in drug delivery research - chances and challenges.

    Science.gov (United States)

    Kempe, Sabine; Metz, Hendrik; Mäder, Karsten

    2010-01-01

    Electron Paramagnetic Resonance (EPR) spectroscopy is a powerful technique to study chemical species with unpaired electrons. Since its discovery in 1944, it has been widely used in a number of research fields such as physics, chemistry, biology and material and food science. This review is focused on its application in drug delivery research. EPR permits the direct measurement of microviscosity and micropolarity inside drug delivery systems (DDS), the detection of microacidity, phase transitions and the characterization of colloidal drug carriers. Additional information about the spatial distribution can be obtained by EPR imaging. The chances and also the challenges of in vitro and in vivo EPR spectroscopy and imaging in the field of drug delivery are discussed.

  14. Transport de paires EPR dans des structures mesoscopiques

    Science.gov (United States)

    Dupont, Emilie

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-09-15

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

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

    Institute of Scientific and Technical Information of China (English)

    He Guang-Qiang; Zeng Gui-Hua

    2006-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-03-15

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

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

    OpenAIRE

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

    2011-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-04-15

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

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

    Science.gov (United States)

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

    2009-04-01

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

  1. EPR character of gadolinium complexes with noncyclic polyether Schiff bases and its solvent effects

    Institute of Scientific and Technical Information of China (English)

    姚克敏; 陈德余; 王晓南; 邓宁

    1996-01-01

    EPR characters of three new gadolinium complexes with noncydic polyether Schiff bases in powder or organic solvents, including various oxyethylene chain lengths and different substituting groups in ligands, are investigated respectively. Some regularities are summed up. The difference of EPR character in various solvents, particularly at different temperatures, has been examined. The ’single peak effect’ due to THF solvent at low temperature is observed for the first time. This phenomenon is explicated.

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

    International Nuclear Information System (INIS)

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

  3. The EPR detection of foods preserved with the use of ionizing radiation

    Science.gov (United States)

    Stachowicz, W.; Burlińska, G.; Michalik, J.; Dziedzic-Gocławska, A.; Ostrowski, K.

    1995-02-01

    Solid constituents extracted from irradiated foods have been examined by the epr (esr) spectroscopy. It has been proved that some epr active species produced by radiation in foods are specific and stable enough to be used for the detection of irradiation treatment. The most promising results have been obtained with bones extracted from frozen raw meat (beef, pork, poultry and fish), with seeds of fruits (dates and figs), with dried mushrooms, gelatin and macaroni.

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

    Science.gov (United States)

    Yordanov, Nicola D.; Aleksieva, Katerina

    2009-03-01

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

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

    International Nuclear Information System (INIS)

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

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

    International Nuclear Information System (INIS)

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

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

    International Nuclear Information System (INIS)

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

  8. EPR of transition metal ions in NZP ceramics

    International Nuclear Information System (INIS)

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

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

    Directory of Open Access Journals (Sweden)

    Mohammad Shakerkhatibi

    2015-09-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1999-03-01

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

  11. Multi-photon transitions and Rabi resonance in continuous wave EPR.

    Science.gov (United States)

    Saiko, Alexander P; Fedaruk, Ryhor; Markevich, Siarhei A

    2015-10-01

    The study of microwave-radiofrequency multi-photon transitions in continuous wave (CW) EPR spectroscopy is extended to a Rabi resonance condition, when the radio frequency of the magnetic-field modulation matches the Rabi frequency of a spin system in the microwave field. Using the non-secular perturbation theory based on the Bogoliubov averaging method, the analytical description of the response of the spin system is derived for all modulation frequency harmonics. When the modulation frequency exceeds the EPR linewidth, multi-photon transitions result in sidebands in absorption EPR spectra measured with phase-sensitive detection at any harmonic. The saturation of different-order multi-photon transitions is shown to be significantly different and to be sensitive to the Rabi resonance. The noticeable frequency shifts of sidebands are found to be the signatures of this resonance. The inversion of two-photon lines in some spectral intervals of the out-of-phase first-harmonic signal is predicted under passage through the Rabi resonance. The inversion indicates the transition from absorption to stimulated emission or vice versa, depending on the sideband. The manifestation of the primary and secondary Rabi resonance is also demonstrated in the time evolution of steady-state EPR signals formed by all harmonics of the modulation frequency. Our results provide a theoretical framework for future developments in multi-photon CW EPR spectroscopy, which can be useful for samples with long spin relaxation times and extremely narrow EPR lines. PMID:26295168

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

    International Nuclear Information System (INIS)

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

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

    Science.gov (United States)

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

    2009-09-01

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

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

    Science.gov (United States)

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

    2010-04-28

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

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

    International Nuclear Information System (INIS)

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

  16. Thermoluminescence and EPR studies on natural petalite crystals

    Energy Technology Data Exchange (ETDEWEB)

    Souza, S.O.; Chubaci, J.F.D.; Watanabe, S. [Department of Nuclear Physics, Institute of Physics, University of Sao Paulo, Sao Paulo, SP (Brazil); Christopher Selvin, P. [NGM College, Pollachi, Tamil Nadu (India); Sastry, M.D. [Bhabha Atomic Research Center, Bombay (India)

    2002-07-07

    Thermally stimulated luminescence of natural mineral petalite (LiAlSi{sub 4}O{sub 10}) crystals was investigated and the possible electron/hole traps responsible for thermoluminescence (TL) emission were identified using optical absorption and electron paramagnetic resonance (EPR) measurements. The glow curves for natural samples, obtained with a heating rate of 4C s{sup -1}, show two glow peaks at 160 deg. C and 330 deg. C. Pre-annealed and subsequently irradiated samples give rise to three glow peaks at 175 deg. C, 340 deg. C and 435 deg. C. An isochronal thermal study established correlation between the first glow peak and Ti{sup 3+}-like trap centre and E'{sub 1}-centre and Al-O{sup -}-Al-like recombination centres. The second TL peak at 340 deg. C may be related to the E{sub 1}' centres formed on irradiation. A mechanism for the observed TL is suggested. (author)

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

    Directory of Open Access Journals (Sweden)

    Enrique Esteban Niebles Nuñez

    2014-09-01

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

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

    OpenAIRE

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

    2011-01-01

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

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

    Science.gov (United States)

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

    2000-01-01

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

  20. EPR study of deoxygenated high-temperature superconductors

    Indian Academy of Sciences (India)

    R J Singh; P K Sharma; Shakeel Khan

    2002-05-01

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

  1. EPR/alanine dosimetry for two therapeutic proton beams

    Science.gov (United States)

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

    2016-02-01

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

  2. Superconducting magnet systems for the ANL EPR design

    International Nuclear Information System (INIS)

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

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

    Science.gov (United States)

    Fattibene, P.; Carosi, A.; DeCoste, V.; Sacchetti, A.; Nucara, A.; Postorino, P.; Dore, P.

    2005-03-01

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

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

    International Nuclear Information System (INIS)

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

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

    Science.gov (United States)

    Basak, Sandip; Chatterjee, Soumili; Chakrapani, Sudha

    2016-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2001-07-21

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

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

    International Nuclear Information System (INIS)

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

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

    Directory of Open Access Journals (Sweden)

    Guo Junwang

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

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

    International Nuclear Information System (INIS)

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Masotti, Paulo Henrique Ferraz

    2006-07-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-07-01

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

  12. Method of semi-automatic high precision potentiometric titration for characterization of uranium compounds; Metodo de titulacao potenciometrica de alta precisao semi-automatizado para a caracterizacao de compostos de uranio

    Energy Technology Data Exchange (ETDEWEB)

    Cristiano, Barbara Fernandes G.; Dias, Fabio C.; Barros, Pedro D. de; Araujo, Radier Mario S. de; Delgado, Jose Ubiratan; Silva, Jose Wanderley S. da, E-mail: barbara@ird.gov.b, E-mail: fabio@ird.gov.b, E-mail: pedrodio@ird.gov.b, E-mail: radier@ird.gov.b, E-mail: delgado@ird.gov.b, E-mail: wanderley@ird.gov.b [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Lopes, Ricardo T., E-mail: ricardo@lin.ufrj.b [Universidade Federal do Rio de Janeiro (LIN/COPPE/UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-Graduacao de Engenharia. Lab. de Instrumentacao Nuclear

    2011-10-26

    The method of high precision potentiometric titration is widely used in the certification and characterization of uranium compounds. In order to reduce the analysis and diminish the influence if the annalist, a semi-automatic version of the method was developed at the safeguards laboratory of the CNEN-RJ, Brazil. The method was applied with traceability guaranteed by use of primary standard of potassium dichromate. The standard uncertainty combined in the determination of concentration of total uranium was of the order of 0.01%, which is better related to traditionally methods used by the nuclear installations which is of the order of 0.1%

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-07-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Zanette, Camila

    2013-07-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-07-01

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

  16. BCL::MP-Fold: membrane protein structure prediction guided by EPR restraints

    CERN Document Server

    Fischer, Axel Walter; Woetzel, Nils; Karakas, Mert; Weiner, Brian; Meiler, Jens

    2015-01-01

    For many membrane proteins the determination of their topology remains a challenge for methods like X-ray crystallography and nuclear magnetic resonance (NMR) spectroscopy. Electron paramagnetic resonance (EPR) spectroscopy has evolved as an alternative technique to study structure and dynamics of membrane proteins. The present study demonstrates the feasibility of membrane protein topology determination using limited EPR distance and accessibility measurements. The BCL::MP-Fold (BioChemical Library membrane protein fold) algorithm assembles secondary structure elements (SSEs) in the membrane using a Monte Carlo Metropolis (MCM) approach. Sampled models are evaluated using knowledge-based potential functions and agreement with the EPR data and a knowledge-based energy function. Twenty-nine membrane proteins of up to 696 residues are used to test the algorithm. The RMSD100 value of the most accurate model is better than 8{\\AA} for twenty-seven, better than 6{\\AA} for twenty-two and better than 4{\\AA} for fifte...

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

    Institute of Scientific and Technical Information of China (English)

    G. G. Fedoruk; O. N. Poklonskaya

    2009-01-01

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

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

    International Nuclear Information System (INIS)

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

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

    International Nuclear Information System (INIS)

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

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

    Science.gov (United States)

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

    2016-07-01

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

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

    International Nuclear Information System (INIS)

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

  2. Interlaboratory trials of the EPR method for the detection of irradiated spices, nutshell and eggshell

    International Nuclear Information System (INIS)

    The Electron Paramagnetic Resonance (EPR) spectrometry detection method for irradiated foods is based on the measurement of free radicals produced in the rigid matrices of foods (e.g. bones, shell, seeds). For certain foods, these free radicals are stable over part of all of the shelf-life of the food. As part of the International Atomic Energy Agency coordinated research programme ADMIT (Analytical Detection Methods for Irradiation Treatment of Foods), two trials of an EPR method for spices and nutshell were undertaken. In the second of these trials eggshell was included for testing. This work describes the two ADMIT trials and identifies some essential elements of a protocol for implementation of the EPR method. (author)

  3. Orientation of crystals in alanine dosimeter assessed by DRS, as seen in EPR spectra evaluation

    International Nuclear Information System (INIS)

    The alanine dosimeter made for evaluation by diffuse light reflection spectrophotometry (ALA/DRS) does not show the effect of orientation of crystals. Supposed deviation from random orientation has been investigated by EPR spectroscopy. EPR investigation shows that in spite of the very fine size of L-alanine crystals, they are oriented in thin layers of the polyethylene matrix. Specially prepared films with deliberately well oriented crystals have confirmed this observation. Our ALA/DRS dosimeter can be evaluated by the EPR method for the concentration of free radicals, providing that the dominating crystal orientation in the dosimetric film is indicated on it as an arrow, and the sample is inserted into the magnetic cavity always in the same orientation as has been done during the calibration operation. (author). 6 refs., 2 figs

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

    Energy Technology Data Exchange (ETDEWEB)

    Maeder, K.; Swartz, H.M. [Dartmouth Univ., Hanover, NH (United States). Dept. of Radiology; Gallez, B. [Louvain Univ., Brussels (Belgium). Dept. of Medicinal Chemistry

    1996-11-01

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

  5. Electron paramagnetic resonance (EPR) in characterization of rocks and minerals

    Energy Technology Data Exchange (ETDEWEB)

    Valezi, D.F.; Mauro, E. di [Universidade Estadual de Londrina (UEL), PR (Brazil). Centro de Ciencias Exatas. Lab. de Fluorescencia e Ressonaancia Paramagnetica Eletronica (LAFLURPE); Zaia, D.A.M.; Carneiro, C.E.A. [Universidade Estadual de Londrina (UEL), PR (Brazil). Centro de Ciencias Exatas. Dept. de Quimica; Costa, A.C.S. da [Universidade Estadual de Maringa (UEM), PR (Brazil). Centro de Ciencias Agrarias. Dept. de Agronomia

    2011-07-01

    Full text. his work is based on the study of several stones and minerals from the Parana state, Brazil. They were analyzed by the Electron Paramagnetic Resonance (EPR) technique. The measurements were made on a spectrometer JEOL (JES-PE-3X), operating on X-band and at room temperature, with the exception of the mineral Goethite, which was measured with temperature variation. In all the samples were determined spectroscopic factors (or g factor) and line widths of paramagnetic species. A great number of the samples showed in their spectra, the presence of iron complexes. Phyllite and shale showed a resonance signal with approximately g = 2, and line width with about 1000 Gauss, which indicates the presence of the hematite mineral hematite in these rocks. Shale and coal samples showed the presence of free radical, it was identified as a very intense signal, centered at about g = 2.003. Phyllite sample showed in its spectra a resonance signal between the third and fourth line of the g marker (Mg O:Mn{sup 2+}) used in the measurements, and also a signal at g = 4.3, these characteristics may indicate the presence of Kaolinite in the sample. Limestone showed a signal with line width of about 600 Gauss, centered around g = 2, this signal is probably due to a mixture of ferrihydrite and some other compound, besides the presence of manganese, displaying a spectra with its six peculiar lines, due to hyperfine splitting. The two different types of limestone presented a overlap of two distinct spectra lines for the manganese, in the first limestone sample, rich in calcite, the existence of these different spectra is a result of the manganese substitution in a single site with different orientations of the calcite; the other limestone sample, this one abundant in dolomite, the existence of these different spectra is the result of the manganese substitution in different dolomite sites, taking the place of calcium and or of the magnesium. Now, we are focusing our research in the

  6. Solvent effect on librational dynamics of spin-labelled haemoglobin by ED- and CW-EPR.

    Science.gov (United States)

    Scarpelli, Francesco; Bartucci, Rosa; Sportelli, Luigi; Guzzi, Rita

    2011-03-01

    Two-pulse, echo-detected electron paramagnetic resonance (ED-EPR) spectra and continuous-wave EPR (CW-EPR) spectra were used to investigate the solvent effect on the librational motion of human haemoglobin spin-labelled on cysteine β93 with the nitroxide derivative of maleimide, 6-MSL. Protein samples fully hydrated in phosphate buffer solution (PBS), in a 60% v/v glycerol/water mixture and in the lyophilized form were measured at cryogenic temperature in the frozen state. The protein librational motion was characterized by the amplitude-correlation time product, τ(c), deduced from the ED-EPR spectra. The librational amplitude, τ(c), was determined independently, from the motionally averaged hyperfine splitting in the CW-EPR spectra, and the librational correlation time, τ(c), was derived from the combination of the pulsed and conventional EPR data. Rapid librational motion of small amplitude was detected in all samples. In each case, the librational dynamics was restricted up to 180 K, beyond which it increased steeply for the hydrated protein in PBS and in the presence of glycerol. In contrast, in the dehydrated protein, the librational dynamics was hindered and less dependent on temperature up to ~240 K. In all samples, deviated from small values only for T > 200 K, where a rapid increase of was evident for the hydrated samples, whereas limited temperature variation was shown in the lyophilized samples. The librational correlation time was in the sub-nanosecond regime and weakly dependent on temperature. The results evidence that solvent favours protein dynamics.

  7. Finnish EPR Olkiluoto 3. The world's first third-generation reactor now under construction

    International Nuclear Information System (INIS)

    The EPR was developed by Framatome and Siemens KWU (the nuclear division of Siemens), whose nuclear activities were combined in January 2001 to form Framatome ANP, now AREVA NP. The French electricity utility EDF (Electricite de France), together with the major German utilities, played an active role in the project. The safety authorities of the two countries joined forces to bring their respective safety standards into line and draw up joint design rules for the new reactor. On December 18, 2003, the consortium formed by AREVA and Siemens - and led by AREVA - signed a contract with TVO for the turnkey construction of the EPR. The overall Olkiluoto 3 project cost has been estimated by TVO at around euros 3 Billion. TVO is responsible for the overall project management and licensing process with the Finnish Safety Authority STUK. In the pre-qualification phase, STUK concluded that the EPR can meet the Finnish licensing requirements. All specific comments will be taken into account for the realization of the project. In January 2005, STUK emphasized in its safety assessment that the evolutionary EPR design compared to predecessor product lines has been further enhanced by AREVA. This paper presents first, The Finnish energy situation (Electricity consumption and supply, Finland's Kyoto CO2 cutback, Competitiveness of nuclear power), and then the EPR in Olkiluoto (General schedule of responsibilities, Important milestones of the project). Finally, the EPR third-generation and advanced reactor is presented with its position in the international competition (Targeted design objectives, Main characteristics, competitiveness, safety, Additional measures to prevent the occurrence of events likely to damage the core, Increased protection against the consequences of core melt)

  8. EPR dosimetry of teeth in past and future accidents: a prospective look at a retrospective method

    Energy Technology Data Exchange (ETDEWEB)

    Haskell, E.H.; Kenner, G.H.; Hayes, R.B. [Utah Univ., Salt Lake City, UT (United States). Center for Applied Dosimetry; Chumak, V.; Shalom, S. [All-Union Scientific Centre of Radiation Medicine, Kiev (Ukraine)

    1996-01-01

    Electron paramagnetic resonance spectroscopy (EPR) of tooth enamel is a relatively new technique for retrospective dosimetry that in the past two years has seen increasing effort towards its development and evaluation. Efforts have centered on determining the accuracy which may be achieved with current measurement techniques as well as the minimum doses detectable. The study was focused on evaluating some factors which influence the accuracy of EPR dosimetry of enamel. Reported are studies on sample intercomparisions, instrumental considerations, and effects of dental x-rays, environmental sunlight and ultraviolet radiation.

  9. Synthesis, EPR, Electronic and Magnetic Studies on Cobalt (II) Complexes of Semicarbazone and Thiosemicarbazone

    International Nuclear Information System (INIS)

    Cobalt (II) complexes having the general composition Co(L2) X2 [where Lisopropyl methyl ketone semicarbazone (LLA), isopropyl methyl ketone thiosemicarbazone (LLB), 4-aminoacetophenone semicarbazone (LLC) and4-aminoacetophenone thiosemicarbazone (LLD) and X=Cl] have been synthesized. All the Co(II) complexes reported here have been characterized by elemental analyses, magnetic moments, IR, electronic and EPR spectral studies. All the complexes were found to have magnetic moments corresponding to three unpaired electrons. The possible geometries of the complexes were assigned on the basis of electronic infrared and EPR spectral studies. (author) = = = = = = = = = = = = = = =

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

    Science.gov (United States)

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

    2011-08-01

    Polyphase continuous excitation based on the Frank sequence is suggested as an alternative to single pulse excitation in EPR. The method allows reduction of the source power, while preserving the excitation bandwidth of a single pulse. For practical EPR implementation the use of a cross-loop resonator is essential to provide isolation between the spin system and the resonator responses to the excitation. Provided that a line broadening of about 5% is acceptable, the cumulative turning angle of the magnetization vector generated by the excitation sequence can be quite large and can produce signal amplitudes that are comparable to that achieved with a higher power 90° pulse. PMID:21737326

  11. Formates and dithionates: sensitive EPR-dosimeter materials for radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Lund, E. [Department of Medicine and Care, Radiation Physics, Faculty of Health Sciences, University of Linkoeping, S-581 85 Linkoeping (Sweden)]. E-mail: eva.lund@imv.liu.se; Gustafsson, H. [Department of Medicine and Care, Radiation Physics, Faculty of Health Sciences, University of Linkoeping, S-581 85 Linkoeping (Sweden); Danilczuk, M. [Chemical Physics Laboratory, IFM, University of Linkoeping, S-581 83 Linkoeping (Sweden); Sastry, M.D. [Chemical Physics Laboratory, IFM, University of Linkoeping, S-581 83 Linkoeping (Sweden); Lund, A. [Chemical Physics Laboratory, IFM, University of Linkoeping, S-581 83 Linkoeping (Sweden); Vestad, T.A. [Department of Physics, University of Oslo, P.O. Box 1048 Blindern, N-0316 Oslo (Norway); Malinen, E. [Department of Physics, University of Oslo, P.O. Box 1048 Blindern, N-0316 Oslo (Norway); Hole, E.O. [Department of Physics, University of Oslo, P.O. Box 1048 Blindern, N-0316 Oslo (Norway); Sagstuen, E. [Department of Physics, University of Oslo, P.O. Box 1048 Blindern, N-0316 Oslo (Norway)

    2005-02-01

    Polycrystalline formates and dithionates are promising materials for EPR dosimetry, as large yields of radiation induced stable radicals are formed with a linear dose response. Rapid spin relaxation rates were detected in many of the substances, indicating that a high microwave power can be applied during EPR acquisition in order to improve sensitivity. Different techniques used to further improve the sensitivity, such as the replacement of {sup 7}Li with {sup 6}Li or exchange of protons with deuterons in the corresponding crystalline matrices and metal ion doping are discussed. It is concluded that formates and dithionates may be up to 10 times as sensitive as L-{alpha}-alanine.

  12. Estimation of radiation levels by EPR measurement of tooth enamel in Indian populations

    Energy Technology Data Exchange (ETDEWEB)

    El-Faramawy, N.A. [GSF-National Research Center for Environment and Health, Institute for Radiation Protection, D-85758 Neuherberg (Germany) and Department of Physics, Faculty of Science, Ain Shams University, Cairo (Egypt)]. E-mail: na_bil@yahoo.com

    2005-02-01

    Enamel from 34 molars from 22 individuals in the general population are used to evaluate the background radiation in six cities in India. The estimation of the background dose for each tooth is evaluated using two EPR methods: the calibration-curve method and the additive-dose method. The variation of the estimated EPR dose with tooth position is investigated by using eight teeth taken from the same person. Contribution of the dental X-ray treatments to the enamel-absorbed dose was evaluated using another 17 teeth exposed from 1 to 10 times.

  13. Improving noise threshold for optical quantum computing with the EPR photon source

    CERN Document Server

    Wei, Z -H; OH, C H; Duan, L -M

    2009-01-01

    We show that the noise threshold for optical quantum computing can be significantly improved by using the EPR-type of photon source. In this implementation, the detector efficiency $\\eta_{d}$ is required to be larger than 50%, and the source efficiency $\\eta_{s}$ can be an arbitrarily small positive number. This threshold compares favorably with the implementation using the single-photon source, where one requires the combined efficiency $\\eta_{d}\\eta_{s}>2/3$. We discuss several physical setups for realization of the required EPR photon source, including the photon emitter from a single-atom cavity.

  14. EPR, mass, IR, electronic, and magnetic studies on copper(II) complexes of semicarbazones and thiosemicarbazones

    Science.gov (United States)

    Chandra, Sulekh; Gupta, Lokesh Kumar

    2005-01-01

    Copper(II) complexes having the general composition Cu(L) 2X 2 [where L = isopropyl methyl ketone semicarbazone (LLA), isopropyl methyl ketone thiosemicarbazone (LLB), 4-aminoacetophenone semicarbazone (LLC), and 4-aminoacetophenone thiosemicarbazone (LLD) and X = Cl -, 1/2SO 42-] have been synthesized. All the Cu(II) complexes reported here have been characterized by elemental analyses, molar conductance, magnetic moment susceptibility, EI mass, 1H NMR, IR, EPR, and electronic spectral studies. All the complexes were found to have magnetic moments corresponding to one unpaired electrons. The possible geometries of the complexes were assigned on the basis of EPR, electronic, and infrared spectral studies.

  15. The first international intercomparison of EPR-dosimetry with teeth: first results

    International Nuclear Information System (INIS)

    Intercomparison of EPR-dosimetric techniques using tooth enamel has been performed in order to check whether the results produced by different laboratories are consistent and accurate. Participants were supposed to evaluate doses applied to pulverized enamel samples, using routine techniques from their laboratories. The intercomparison has demonstrated a great variety of methods used for dose reconstruction. Peculiarities of experimental approaches are discussed systematically in terms of procedure for recording the EPR-spectra, determination of the amplitude of the radiation induced signal, determination of the dose, and error propagation. (Author)

  16. Manufacturing of nozzle shell with integral flange for EPR reactor pressure vessel and its properties

    International Nuclear Information System (INIS)

    EPR (EPR: European Pressurized Water Reactor) has been developed to achieve higher output (1,600 MW) and longer plant life (60 years), compared with the conventional unclear reactors, and the first commercial reactor was introduced in Finland no.5/Olkiluoto no.3. The integrated mono-block design was applied for nozzle shell flange instead of welded conventional flange and nozzle shell. And due to set-on type nozzles, a 600 ton ingot was required for this part. JSW successfully completed the manufacturing of first nozzle shell with integral flange 11 months after melting. This report summarizes manufacturing technology and process, and properties of nozzle shell with integral flange. (author)

  17. Characterization of lithium formate EPR dosimeters for high dose applications - Comparison with alanine

    International Nuclear Information System (INIS)

    Lithium formate and L-α-alanine (alanine) EPR dosimeters were irradiated to doses from 100 Gy to 100 kGy. The irradiations were mainly performed at a Gammacell irradiator with dose rate of approximately 5.5 kGy h-1. Both the peak-to-peak amplitude of the first derivative EPR spectrum and the area under the EPR absorption spectrum were extracted, and the resulting dose dependence of these EPR signal intensity parameters was analyzed. The dependence of the peak-to-peak width of the central resonance in the first derivative EPR spectrum on the dose was also elucidated. In addition, the dependence on dose rate and irradiation temperature for the two materials were measured. Dosimeters were given doses from 100 Gy to 10 kGy at two different Gammacells with dose rates of 5.5 kGy h-1 and 0.6 kGy h-1, respectively, and the results were compared. Furthermore, the EPR signal intensities for dosimeters irradiated to 1 kGy at temperatures from 11 oC to 40 oC were analyzed. By fitting an 'exponential rise to maximum'-function to the dependence of the area under the EPR absorption spectrum on the dose, saturation doses of 53 kGy and 87 kGy for lithium formate and alanine, respectively, were found. Lower estimates were found when analyzing the dose dependence of the peak-to-peak amplitude. Furthermore, the peak-to-peak width was found to increase for doses above 10 kGy. No dose rate dependence for any of the studied materials was observed and the temperature coefficients at 25 oC (i.e. change in dosimeter signal per oC change in irradiation temperature) were 0.154% K-1 and 0.161% K-1 for lithium formate and alanine, respectively. This work demonstrates that lithium formate EPR dosimeters may be suitable for high dose applications, but their signals saturate at lower doses than alanine. The saturation doses found for both materials may be used in theoretical calculations of the dosimeter response following hadron beam irradiations.

  18. EFFECT OF CADMIUM(II) ON FREE RADICALS IN DOPA-MELANIN TESTED BY EPR SPECTROSCOPY.

    Science.gov (United States)

    Zdybel, Magdalena; Pilawa, Barbara; Chodurek, Ewa

    2015-01-01

    Electron paramagnetic resonance (EPR) spectroscopy may be applied to examine interactions of melanin with metal ions and drugs. In this work EPR method was used to examination of changes in free radical system of DOPA-melanin--the model eumelanin after complexing with diamagnetic cadmium(II) ions. Cadmium(II) may affect free radicals in melanin and drugs binding by this polymer, so the knowledge of modification of properties and free radical concentration in melanin is important to pharmacy. The effect of cadmium(II) in different concentrations on free radicals in DOPA-melanin was determined. EPR spectra of DOPA-melanin, and DOPA-melanin complexes with cadmium(II) were measured by an X-band (9.3 GHz) EPR spectrometer produced by Radiopan (Poznań, Poland) and the Rapid Scan Unit from Jagmar (Krak6w, Poland). The DOPA (3,4-dihydroxyphenylalanine) to metal ions molar ratios in the reaction mixtures were 2:1, 1:1, and 1: 2. High concentrations of o-semiquinone (g ~2.0040) free radicals (~10(21)-10(22) spin/g) characterize DOPA-melanin and its complexes with cadmium(II). Formation of melanin complexes with cadmium(II) increase free radical concentration in DOPA-melanin. The highest free radical concentration was obtained for DOPA-melanin-cadmium(II) (1:1) complexes. Broad EPR lines with linewidths: 0.37-0.73 mT, were measured. Linewidths increase after binding of cadmium(II) to melanin. Changes of integral intensities and linewidths with increasing microwave power indicate the homogeneous broadening of EPR lines, independently on the metal ion concentration. Slow spin-lattice relaxation processes existed in all the tested samples, their EPR lines saturated at low microwave powers. Cadmium(II) causes fastening of spin-lattice relaxation processes in DOPA-melanin. The EPR results bring to light the effect of cadmium(II) on free radicals in melanin, and probably as the consequence on drug binding to eumelanin.

  19. Zigzagging causility model of EPR correlations and on the interpretation of quantum mechanics

    International Nuclear Information System (INIS)

    Being formalized inside the S-matrix scheme, the zigzagging causility model of EPR correlations has full Lorentz and CPT invariance. EPR correlations, proper or reversed, and Wheeler's smoky dragon metaphor are respectively pictured in a spacetime or in the momentum-energy space, as V-shaped, anti LAMBDA-shaped, or C-shaped ABC zigzags, with a summation at B over virtual states absolute value B>=*. The reversibility = * implies that causality is CPT-invariant, or arrowless, at the microlevel. Arrowed causality is a macroscopic emergence, corollary to wave retardation and probability increase. Factlike irreversibility states repression, not suppression, of blind statistical retrodiction- that is, of final cause

  20. Characteristics and economy of the European reactor of pressurized water (EPR); Caracteristicas y economia del reactor europeo de agua a presion (EPR)

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz V, J.; Ramirez S, J.R.; Palacios H, J.C. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)]. e-mail: jov@nuclear.inin.mx

    2005-07-01

    The high current costs of the fossil fuels, have propitiated that the industries of electric power generation in the world reconsider the nuclear option as medium of generation. In Europe, the more recently contracted nuclear power plant is that of Olkiluoto-III in Finland that waits it enters in operation at the end of 2009. The reactor that will be installed in this power plant will be a prototype of pressurized water reactor of the companies AREVA and EDF. In this work they are described the reactor EPR and the major components of the nuclear power plant as well as the main characteristics of safety and the flexibility of the operation of the EPR. The supposed costs reported in different sources of information are also described and calculated with information provided by the manufacturer company. (Author)

  1. Franco-German cooperation for the physical protection of the EPR reactor; Cooperation franco-allemande dans le domaine de la protection physique, appliquee au projet EPR

    Energy Technology Data Exchange (ETDEWEB)

    Jalouneix, J. [CEA/Fontenay aux Roses, Inst. de Protection et de Surete Nucleaire (IPSN), 92 (France); Hagemann, A. [Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) mbH, Garching (Germany)

    2001-02-01

    This article presents the proceeding that has been followed in the EPR (European pressurized water reactor) project concerning physical protection against malevolent actions and robbery of nuclear materials. Before the different options of the nuclear island were definitely set, a task group had been constituted to examine if these options could hamper the setting of physical protection measures that are required by the legislation of the 2 countries. Another group composed of experts from IPSN/GRS (Institut de Protection et de Surete Nucleaire / Gesellschaft fur Anlagen und Reaktorsicherheit) had the task to define common requirements concerning the physical protection of reactors in Germany and in France. In this framework the EPR project team has prepared a technical document reviewing the different dispositions that have been retained to assure the physical protection of the reactor. (A.C.)

  2. Polypropylene/ethylene-propylene rubber (PP/EPR blends for the automotive industry: Basic correlations between EPR-design and shrinkage

    Directory of Open Access Journals (Sweden)

    G. D. Potter

    2014-04-01

    Full Text Available The influence of the phase morphology on the shrinkage of injection molded plates from reactor based PP/EPR blends was investigated using a model series. The morphology of the dispersed phase – in terms of size and shape of the rubber particles as determined from scanning electron microscopy (SEM – was found to correlate fairly well with the shrinkage determined in the flow and transverse direction of injection molded plates. In this respect it turned out to be elementary to consider the anisotropy of the particles rather than their average size alone. Additionally, the effect of the EPR design on the coefficient of linear thermal expansion (CLTE was evaluated and brought into a relationship with the blend morphology.

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

    Directory of Open Access Journals (Sweden)

    Eddy Sánchez Téllez

    2011-10-01

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

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

    Directory of Open Access Journals (Sweden)

    Ridel Oscar García Mora

    2014-07-01

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

  5. Four-channel surface coil array for sequential CW-EPR image acquisition.

    Science.gov (United States)

    Enomoto, Ayano; Emoto, Miho; Fujii, Hirotada; Hirata, Hiroshi

    2013-09-01

    This article describes a four-channel surface coil array to increase the area of visualization for continuous-wave electron paramagnetic resonance (CW-EPR) imaging. A 776-MHz surface coil array was constructed with four independent surface coil resonators and three kinds of switches. Control circuits for switching the resonators were also built to sequentially perform EPR image acquisition for each resonator. The resonance frequencies of the resonators were shifted using PIN diode switches to decouple the inductively coupled coils. To investigate the area of visualization with the surface coil array, three-dimensional EPR imaging was performed using a glass cell phantom filled with a solution of nitroxyl radicals. The area of visualization obtained with the surface coil array was increased approximately 3.5-fold in comparison to that with a single surface coil resonator. Furthermore, to demonstrate the applicability of this surface coil array to animal imaging, three-dimensional EPR imaging was performed in a living mouse with an exogenously injected nitroxyl radical imaging agent. PMID:23832070

  6. Quality assessment of information about medications in primary care electronic patient record (EPR systems

    Directory of Open Access Journals (Sweden)

    Maria Pous

    2010-06-01

    Conclusions This project highlighted the poor quality of drug information provided by these EPR programmes. The ten-item tool seems suitable for assessing their quality. Based on this analysis, we have proposed a set of ten quality standards for prescribing software.

  7. EPR safety. Consideration of the internal and external hazards in the safety studies

    International Nuclear Information System (INIS)

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

  8. Electronic paramagnetic resonance (EPR) for the study of ascorbyl radical and lipid radicals in marine organisms.

    Science.gov (United States)

    González, Paula Mariela; Aguiar, María Belén; Malanga, Gabriela; Puntarulo, Susana

    2013-08-01

    Electron paramagnetic resonance (EPR) spectroscopy detects the presence of radicals of biological interest, such as ascorbyl radical (A(•)) and lipid radicals. A(•) is easily detectable by EPR even in aqueous solution at room-temperature. Under oxidative conditions leading to changes in total ascorbate (AH(-)) content, the A(•)/AH(-) ratio could be used to estimate early oxidative stress in the hydrophilic milieu. This methodology was applied to a wide range of aquatic systems including algae, sea urchin, limpets, bivalves and fish, under physiological and oxidative stress conditions as well. The A(•)/AH(-) ratio reflected the state of one part of the oxidative defense system and provided an early and simple diagnosis of environmental stressing conditions. Oxidative damage to lipids was assessed by the EPR-sensitive adduct formation that correlates well with cell membrane damage with no interference from other biological compounds. Probe instability, tissue metabolism, and lack of spin specificity are drawback factors for employing EPR for in vivo determination of free radicals. However, the dependability of this technique, mostly by combining it with other biochemical strategies, enhances the value of these procedures as contributors to the knowledge of oxidative condition in aquatic organisms. PMID:23485428

  9. On the Correlation between EPR and Positron Annihilation Measurements on gamma-Irradiated Acetyl Methionine

    DEFF Research Database (Denmark)

    Eldrup, Morten Mostgaard; Lund-Thomsen, E.; Mogensen, O. E.

    1972-01-01

    The dose dependence of the relative EPR signal intensity and positron lifetime spectrum was measured for γ‐irradiated acetyl methionine in the dose range from 0 to 30 Mrad. Angular correlation measurements were performed for the doses 0 and 30 Mrad. The result of the irradiation was the creation...

  10. Radiation Dosimetry of Dental Enamel Using X-Band and Q-Band EPR Spectroscopy

    Science.gov (United States)

    de, Tania; Romanyukha, Alex; Pass, Barry; Misra, Prabhakar

    2010-02-01

    Electron paramagnetic resonance (EPR) dosimetry of tooth enamel can be used for individual dose reconstruction following radiation accidents. The purpose of this study was to develop a rapid, minimally invasive technique for obtaining a sample of dental enamel small enough to not disturb the structure and functionality of a tooth and to improve the sensitivity of the spectral signals using X-band (9.4 GHz) and Q-band (34 GHz) EPR spectroscopy. EPR measurements in X-band were performed on 100 mg isotropic powdered enamel samples and Q-band measurements done on 4 mg (1x1x3 mm) enamel biopsy samples. All samples were obtained from discarded teeth collected during normal dental treatment. In order to study the variation of the Radiation-Induced Signal (RIS) at different orientations in the applied magnetic field samples were placed in the resonance cavity for Q-band EPR. In X-band spectra, the RIS is distinct from the ``native'' radiation-independent signal only for doses > 0.5Gy. Q-band, however, resolves the RIS and ``native'' signals and improves sensitivity by a factor of 20 enabling measurements in 2-4 mg tooth enamel samples. )

  11. Investigations on resolution enhancement in EPR by means of electron spin echoes

    International Nuclear Information System (INIS)

    The electron spin echo technique has been applied in four types of experiments: the measurement of electric field induced shifts of the EPR line; the detection of electron spin echo ENDOR; a relaxation measurement and the measurement of hyperfine interactions via the nuclear modulation effect. (Auth.)

  12. Comparative study between two austenitic steels with the EPR (Electrochemical Potentiokinetic Reactivation) technique

    International Nuclear Information System (INIS)

    In the mid 19704s, the intergranular corrosion with stress corrosion cracking (IGSCC) have been identified as a greater problem in Boiling Water Reactors BWR in several places of the world. The Electrochemical Potentiokinetic Reactivation - Single Loop (EPR-SL) test and the Double Loop (EPR-DL) test, were developed as methods for measuring the Degree of Sensitization (DOS), show sensitised materials at subject to Intergranular Corrosion. In Mexico, the Laguna Verde4s reactor is BWR type and many of its principal components was built with AISI 304 stainless steels, while that in VVER reactors as well as Juragua4s reactor in Cuba is used 321 Stainless stell in its Russian equivalent designation 08Ch18N10T. In this work, were studied 304 and 08Ch18N10T stainless steels by means of EPR-SL, EPR-DL and ASTM A-262 techniques, they have been found a good correlation for 304 steel but not in 08Ch18N10T steel and was proposed one modification in the criterion by the evaluation on the sensitisation in this steels. Finally, both materials were welded with procedures used in the nuclear industry, by Slow Strain Rate Test (SSRT) to determine the Stress Corrosion Cracking SCC susceptibility, and subsequently the susceptibility to localized corrosion was studied by means of Cyclic Polarization test and the uniform corrosion rate in a solution with chlorides by the Tafel plot, Potentiodynamic Anodic Polarization Resistance. (Author)

  13. Measuring precarious employment in times of crisis: the revised Employment Precariousness Scale (EPRES in Spain

    Directory of Open Access Journals (Sweden)

    Alejandra Vives

    2015-09-01

    Conclusion: The revised version of the EPRES demonstrated good metric properties and improved sensitivity to worker vulnerability and employment instability among permanent workers. Furthermore, it was sensitive to increased levels of precariousness in some dimensions despite decreases in others, demonstrating responsiveness to the context of the economic crisis affecting the Spanish labour market.

  14. VO2+ ions in zinc lead borate glasses studied by EPR and optical absorption techniques.

    Science.gov (United States)

    Prakash, P Giri; Rao, J Lakshmana

    2005-09-01

    Electron paramagnetic resonance (EPR) and optical absorption spectra of vanadyl ions in zinc lead borate (ZnO-PbO-B2O3) glass system have been studied. EPR spectra of all the glass samples exhibit resonance signals characteristic of VO2+ ions. The values of spin-Hamiltonian parameters indicate that the VO2+ ions in zinc lead borate glasses were present in octahedral sites with tetragonal compression and belong to C4V symmetry. The spin-Hamiltonian parameters g and A are found to be independent of V2O5 content and temperature but changing with ZnO content. The decrease in Deltag( parallel)/Deltag( perpendicular) value with increase in ZnO content indicates that the symmetry around VO2+ ions is more octahedral. The decrease in intensity of EPR signal above 10 mol% of V2O5 is attributed to a fall in the ratio of the number of V4+ ions (N4) to the number of V5+ ions (N5). The number of spins (N) participating in resonance was calculated as a function of temperature for VO2+ doped zinc lead borate glass sample and the activation energy was calculated. From the EPR data, the paramagnetic susceptibility was calculated at various temperatures and the Curie constant was evaluated from the 1/chi-T graph. The optical absorption spectra show single absorption band due to VO2+ ions in tetragonally distorted octahedral sites. PMID:16043053

  15. Producing the event ready two photon polarization EPR state with linear optics devices

    OpenAIRE

    Xiang-Bin, Wang

    2002-01-01

    We propose a scheme to produce the maximally two photon polarization entangled state(EPR state) with single photon sources and the linear optics devices. In particular, our scheme requires the photon detectors only to distinguish the vacuum and non-vacuum Fock number states. A sophisticated photon detector distinguishing one or two photon states is unnecessary.

  16. The acid-catalyzed interaction of melanin with nitrite ions. An EPR investigation

    OpenAIRE

    Matuszak Zenon; Chignell Collin F.; Reszka Krzysztof J.

    2015-01-01

    The interaction of synthetic dihydroxyphenylalanine (DOPA) melanin (DM) with nitrite ions, NO2−, in the pH 3.6–7.0 range, has been investigated using electron paramagnetic resonance (EPR). We found that especially at pH

  17. Interaction of formin FH2 with skeletal muscle actin. EPR and DSC studies.

    Science.gov (United States)

    Kupi, Tünde; Gróf, Pál; Nyitrai, Miklós; Belágyi, József

    2013-10-01

    Formins are highly conserved proteins that are essential in the formation and regulation of the actin cytoskeleton. The formin homology 2 (FH2) domain is responsible for actin binding and acts as an important nucleating factor in eukaryotic cells. In this work EPR and DSC were used to investigate the properties of the mDia1-FH2 formin fragment and its interaction with actin. MDia1-FH2 was labeled with a maleimide spin probe (MSL). EPR results suggested that the MSL was attached to a single SH group in the FH2. In DSC and temperature-dependent EPR experiments we observed that mDia1-FH2 has a flexible structure and observed a major temperature-induced conformational change at 41 °C. The results also confirmed the previous observation obtained by fluorescence methods that formin binding can destabilize the structure of actin filaments. In the EPR experiments the intermolecular connection between the monomers of formin dimers proved to be flexible. Considering the complex molecular mechanisms underlying the cellular roles of formins this internal flexibility of the dimers is probably important for manifestation of their biological functions.

  18. Application of jade samples for high-doses using the EPR technique

    International Nuclear Information System (INIS)

    Full text: The dosimeter characteristics of jade samples were studied for application in dosimetry. Jade is the common denomination of two silicates: jadeite, and actinolite, which belong respectively to the subclasses of pyroxenes and amphiboles. Green materials were acquired as jade with origin in New Zealand, Austria and USA. The dosimetric properties of these materials were already studied using the thermoluminescence technique, showing their potential use for high dose dosimetry. At the Metrology Laboratory of IPEN, Sao Paulo, glasses, sand and Brazilian natural stones have been studied in relation to their dosimetric properties for high-doses using different techniques. In the present work jade samples were studied using the electronic paramagnetic resonance (EPR) technique to investigate the potential applications in gamma radiation dosimetry. The EPR spectra of different jade samples were obtained after irradiation with different absorbed doses of 50 Gy up to 10 kGy. The jade samples present one g-factor at 2.010 that grows with the absorbed dose; it can be attributed to an electron center. The EPR spectra obtained of the USA jade samples and their main dosimetric properties as reproducibility, calibration curves and energy dependence were investigated. There is no evidence in the literature about jade applications in radiation dosimetry using the EPR technique; only crystallographic aspects of synthetic samples were compared to natural ones

  19. Simple group password-based authenticated key agreements for the integrated EPR information system.

    Science.gov (United States)

    Lee, Tian-Fu; Chang, I-Pin; Wang, Ching-Cheng

    2013-04-01

    The security and privacy are important issues for electronic patient records (EPRs). The goal of EPRs is sharing the patients' medical histories such as the diagnosis records, reports and diagnosis image files among hospitals by the Internet. So the security issue for the integrated EPR information system is essential. That is, to ensure the information during transmission through by the Internet is secure and private. The group password-based authenticated key agreement (GPAKE) allows a group of users like doctors, nurses and patients to establish a common session key by using password authentication. Then the group of users can securely communicate by using this session key. Many approaches about GAPKE employ the public key infrastructure (PKI) in order to have higher security. However, it not only increases users' overheads and requires keeping an extra equipment for storing long-term secret keys, but also requires maintaining the public key system. This investigation presents a simple group password-based authenticated key agreement (SGPAKE) protocol for the integrated EPR information system. The proposed SGPAKE protocol does not require using the server or users' public keys. Each user only remembers his weak password shared with a trusted server, and then can obtain a common session key. Then all users can securely communicate by using this session key. The proposed SGPAKE protocol not only provides users with convince, but also has higher security. PMID:23328913

  20. Oak Ridge Tokamak Experimental Power Reactor study, 1976. Part I. EPR summary

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, M.; McAlees, D.G.; Shannon, T.E.; Flanagan, C.A.; Lue, J.W.

    1977-04-01

    The study of the Tokamak Experimental Power Reactor (EPR) has been performed by the Oak Ridge National Laboratory (ORNL) for the Energy Research and Development Administration Division of Magnetic Fusion Energy (ERDA-DMFE) over a two-year period. This second year's work builds integrally upon the earlier efforts. Therefore, the following format has been adopted for this report. Part 1, entitled ''EPR Summary,'' contains a brief discussion of all facets of the work done this year. The technical areas discussed in Part 1 include the Reference Design itself; the underlying plasma engineering base; the supporting technical evaluations in the areas of magnet systems, nuclear engineering, and general engineering; and the major research, development, and demonstration needs that have been identified. Each of these areas is then discussed fully in separate technical memoranda, which have been issued as Parts 2-6. Where appropriate, the essential elements of previous interim reports have been included in order to provide a self-consistent, readable report. These earlier reports, Basic Considerations and Initiation of Studies (ORNL/TM-4853), EPR Scoping Study (ORNL/TM-5038), and EPR Reference Design (ORNL/TM-5042), can be consulted for a more complete discussion of the entire study.

  1. A New Q-Band EPR Probe for Quantitative Studies of Even Electron Metalloproteins

    Science.gov (United States)

    Petasis, D. T.; Hendrich, M. P.

    1999-02-01

    Existing Q-band (35 GHz) EPR spectrometers employ cylindrical cavities for more intense microwave magnetic fields B1, but are so constructed that only one orientation between the external field B and B1is allowed, namely the B ⊥ B1orientation, thus limiting the use of the spectrometer to measurements on Kramers spin systems (odd electron systems). We have designed and built a Q-band microwave probe to detect EPR signals in even electron systems, which operates in the range 2 K ≤ T ≤ 300 K for studies of metalloprotein samples. The cylindrical microwave cavity operates in the TE011mode with cylindrical wall coupling to the waveguide, thus allowing all orientations of the external magnetic field B relative to the microwave field B1. Such orientations allow observation of EPR transitions in non-Kramers ions (even electron) which are either forbidden or significantly weaker for B ⊥ B1. Rotation of the external magnetic field also permits easy differentiation between spin systems from even and odd electron oxidation states. The cavity consists of a metallic helix and thin metallic end walls mounted on epoxy supports, which allows efficient penetration of the modulation field. The first quantitative EPR measurements from a metalloprotein (Hemerythrin) at 35 GHz with B1‖ B are presented.

  2. Irradiated bivalve mollusks: Use of EPR spectroscopy for identification and dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Alberti, Angelo, E-mail: aalberti@isof.cnr.it [CNR-ISOF, Area della Ricerca di Bologna, Via P. Gobetti 101, Bologna I-40129 (Italy); Chiaravalle, Eugenio [Istituto Zooprofilattico Sperimentale della Puglia e Basilicata, Via Manfredonia 20, Foggia I-71100 (Italy); Fuochi, Piergiorgio; Macciantelli, Dante [CNR-ISOF, Area della Ricerca di Bologna, Via P. Gobetti 101, Bologna I-40129 (Italy); Mangiacotti, Michele, E-mail: michelemangiacotti@libero.it [Istituto Zooprofilattico Sperimentale della Puglia e Basilicata, Via Manfredonia 20, Foggia I-71100 (Italy); Marchesani, Giuliana [Istituto Zooprofilattico Sperimentale della Puglia e Basilicata, Via Manfredonia 20, Foggia I-71100 (Italy); Plescia, Elena [CNR-ISOF, Area della Ricerca di Bologna, Via P. Gobetti 101, Bologna I-40129 (Italy)

    2011-12-15

    High energy radiation treatment of foodstuff for microbial control and shelf-life extension is being used in many countries. However, for consumer protection and information, the European Union has adopted the Directives 1999/2/EC and 1999/3/EC to harmonize the rules concerning the treatment and trade of irradiated foods in EU countries. Among the validated methods to detect irradiated foods the EU directives also include Electron Paramagnetic Resonance (EPR/ESR) spectroscopy. We describe herein the use of EPR for identification of four species of bivalve mollusks, i.e. brown Venus shells (Callista chione), clams (Tapes semidecussatus), mussels (Mytilus galloprovincialis) and oysters (Ostrea edulis) irradiated with {sup 60}Co {gamma}-rays. EPR could definitely identify irradiated seashells due to the presence of long-lived free radicals, primarily CO{sub 2}{sup -}, CO{sub 3}{sup 3-}, SO{sub 2}{sup -} and SO{sub 3}{sup -} radical anions. The presence of other organic free radicals, believed to originate from conchiolin, a scleroprotein present in the shells, was also ascertained. The use of one of these radicals as a marker for irradiation of brown Venus shells and clams can be envisaged. We also propose a dosimetric protocol for the reconstruction of the administered dose in irradiated oysters. - Highlights: > EPR spectroscopy is confirmed a valuable identification tool for irradiated mollusks. > A conchiolin-derived radical can be used as irradiation marker for some mollusks. > A reliable protocol is outlined for dose reconstruction of irradiated oysters.

  3. EDF will set up its first European Pressurized water Reactor (EPR) in Flamanville

    International Nuclear Information System (INIS)

    The EDF decision to set up an European Pressurized water Reactor (EPR) in its Flamanville site is a second commercial success for this new generation of reactors and prefigure the replacement of some of these plants which begin to age. (O.M.)

  4. Study of EPR spectra of radicals from ionizing radiation interaction with alanine and 4-hydroxyproline samples

    International Nuclear Information System (INIS)

    A number of stable chemical radicals result following irradiation with ionizing rays of α-β-alanine and 4-hydroxyproline. They could be put into evidence using post-irradiation EPR technique. Analysis and inter-comparison of spectra signals become important for a correct assignment of structure and, subsequently of generating mechanisms in amino acids irradiated samples. (author)

  5. A 5 tesla superconducting magnet and cryostats for an EPR/FMR spectrometer

    NARCIS (Netherlands)

    Reuvekamp, E.M.C.M.; Gerritsma, G.J.; Kate, ten H.H.J.; Klundert, van de L.J.M.

    1988-01-01

    A description is given of the cryogenic part of an electron paramagnetic resonance (EPR)/ferromagnetic resonance (FMR) spectrometer using Ka-band (26.5-40 GHz) and U-band (40-60 GHz) frequencies for resonance measurements on large magnetic thin-films. The unit has two cryostats; the first has a room

  6. Study of Thermal Properties of Mixed (PP/EPR/ABS with Five Model Compatibilizers

    Directory of Open Access Journals (Sweden)

    Pierre Marcel Anicet Noah

    2016-01-01

    Full Text Available The influences of incorporating compatibilizers E-EA-MAH, E-MA-GMA, E-AM, SEBS KRATON G, or PP-g-MAH on the thermal properties of mixed (polypropylene/ethylene propylene rubber/acrylonitrile butadiene styrene (PP/EPR/ABS have been investigated. DSC investigations have revealed that the incorporation of 5% of ABS in the copolymer (PP/EPR does not fundamentally affect the thermal properties of the basic copolymer; additionally, the addition of 1.5% of each of the compatibilizers in the basic mixture does not significantly alter the crystallization temperature values and the melting of the -P- sequences. There is a variation of melting enthalpy values of the -P- sequences of 18.23% using SEBS KRATON G and of 10.38% using E-AM-GMA. When the rate of each of the compatibilizers increases to 5%, overall crystallization enthalpies of -P- sequences are almost kept unchanged, except for the case of using the compatibilizer E-AM-GMA with a variation of 8.42%. There is a minor variation of the melting enthalpy of -P- sequences with higher levels of compatibilizer. The incorporation of 5% ABS copolymer in the PP/EPR does not significantly alter the thermal properties of the basic structure of (PP/EPR/ABS.

  7. High-frequency EPR and ENDOR spectroscopy on semiconductor quantum dots

    NARCIS (Netherlands)

    Baranov, P.G.; Orlinskii, S.B.; de Mello Donega, C.; Schmidt, J.

    2010-01-01

    It is shown that high-frequency electron paramagnetic resonance (EPR) and electron-nuclear double resonance (ENDOR) spectroscopy are excellent tools for the investigation of the electronic properties of semiconductor quantum dots (QDs). The great attractions of these techniques are that, in contrast

  8. Comparative EPR study CO2− radicals in modern and fossil tooth enamel

    International Nuclear Information System (INIS)

    Comparative EPR investigation of CO2− radicals in modern (γ-irradiated) and fossil samples of tooth enamel was performed. The samples studied were the enamel powders and plates, the latter demonstrating an orientation dependence of EPR spectra in an external magnetic field. It was found that the ratio between the axial and orthorhombic CO2− centers amounts appears to be different for modern and fossil enamels. This ratio can be estimated by modeling of EPR spectra lineshape of powders or, in the case of plates, from the orientation dependence of EPR spectra in an external magnetic field. It was assumed that the difference between modern and fossil enamels is caused by the transformation, in the course of time, of orthorhombic CO2− centers into axial ones. The equations that describe this process were deduced. Their solutions show that the ratio between the amounts of the axial and orthorhombic centers does not depend on the dose rate. This finding can be used for the development of the method to determine the fossil enamel age avoiding the determination of the annual dose. - Highlights: • Ratio CO2−(axial)/CO2−(orthorhombic) is different for modern and fossil enamels. • Difference is caused by the transformation CO2−(or) → CO2− (ax), during lifetime. • Ratio CO2− (ax)/CO2− (or) does not depend on the dose rate. • Opportunity of enamel age determination avoiding annual dose estimation is discussed

  9. Sonoporation enhances liposome accumulation and penetration in tumors with low EPR.

    Science.gov (United States)

    Theek, Benjamin; Baues, Maike; Ojha, Tarun; Möckel, Diana; Veettil, Seena Koyadan; Steitz, Julia; van Bloois, Louis; Storm, Gert; Kiessling, Fabian; Lammers, Twan

    2016-06-10

    The Enhanced Permeability and Retention (EPR) effect is a highly variable phenomenon. To enhance EPR-mediated passive drug targeting to tumors, several different pharmacological and physical strategies have been evaluated over the years, including e.g. TNFα-treatment, vascular normalization, hyperthermia and radiotherapy. Here, we systematically investigated the impact of sonoporation, i.e. the combination of ultrasound (US) and microbubbles (MB), on the tumor accumulation and penetration of liposomes. Two different MB formulations were employed, and their ability to enhance liposome accumulation and penetration was evaluated in two different tumor models, which are both characterized by relatively low levels of EPR (i.e. highly cellular A431 epidermoid xenografts and highly stromal BxPC-3 pancreatic carcinoma xenografts). The liposomes were labeled with two different fluorophores, enabling in vivo computed tomography/fluorescence molecular tomography (CT-FMT) and ex vivo two-photon laser scanning microscopy (TPLSM). In both models, in spite of relatively high inter- and intra-individual variability, a trend towards improved liposome accumulation and penetration was observed. In treated tumors, liposome concentrations were up to twice as high as in untreated tumors, and sonoporation enhanced the ability of liposomes to extravasate out of the blood vessels into the tumor interstitium. These findings indicate that sonoporation may be a useful strategy for improving drug targeting to tumors with low EPR. PMID:26878973

  10. Characteristic of paramagnetic centres in burnt clay and pottery by the EPR method

    International Nuclear Information System (INIS)

    The samples of natural clay and pottery have been investigated by using electron paramagnetic resonance (EPR) method. Because of young age (100-5000 years old) of these materials and the presence of iron compounds the big doses (1-200kGy) of irradiation have been used. The authors investigated whole material without quartz extracting from acid washing. In natural clay the EPR lines were observed which disappear after clay burning and they were also not present in EPR spectrum of pottery. After clay burning at temperatures similar to these at which pottery was burnt the spectra of clay became similar to pottery spectra. These EPR spectra have also similar hyperfine structure for which the g factors are equal g1=2.0595, g2=2.0079, and g3=2.0018 for clay and g1=2.0602, g2=2.0079 and g3=2.0019 for pottery. For these lines the [AlO4]0 centre in quartz was ascribed

  11. Three-Party Simultaneous Quantum Secure Direct Communication Scheme with EPR Pairs

    Institute of Scientific and Technical Information of China (English)

    WANG Mei-Yu; YAN Feng-Li

    2007-01-01

    We present a scheme for three-party simultaneous quantum secure direct communication by using EPR pairs.In the scheme, three legitimate parties can simultaneously exchange their secret messages. The scheme is also proven to be secure against the intercept-and-resend attack, the disturbance attack and the entangled-andmeasure attack.

  12. How can EPR spectroscopy help to unravel molecular mechanisms of flavin-dependent photoreceptors?

    Directory of Open Access Journals (Sweden)

    Daniel eNohr

    2015-09-01

    Full Text Available Electron paramagnetic resonance (EPR spectroscopy is a well-established spectroscopic method for the examination of paramagnetic molecules. Proteins can contain paramagnetic moieties in form of stable cofactors, transiently formed intermediates, or spin labels artificially introduced to cysteine sites. The focus of this review is to evaluate potential scopes of application of EPR to the emerging field of optogenetics. The main objective for EPR spectroscopy in this context is to unravel the complex mechanisms of light-active proteins, from their primary photoreaction to downstream signal transduction. An overview of recent results from the family of flavin-containing, blue-light dependent photoreceptors is given. In detail, mechanistic similarities and differences are condensed from the three classes of flavoproteins, the cryptochromes, LOV (Light-oxygen-voltage, and BLUF (blue-light using FAD domains. Additionally, a concept that includes spin-labeled proteins and examination using modern pulsed EPR is introduced, which allows for a precise mapping of light-induced conformational changes.

  13. Characterization of lithium formate EPR dosimeters for high dose applications – comparison with alanine

    DEFF Research Database (Denmark)

    Waldeland, Einar; Helt-Hansen, Jakob; Malinen, Eirik

    2011-01-01

    signal per ºC change in irradiation temperature) were 0.154 % K−1 and 0.161 % K−1 for lithium formate and alanine, respectively. This work demonstrates that lithium formate EPR dosimeters may be suitable for high dose applications, but their signals saturate at lower doses than alanine. The saturation...

  14. Electron paramagnetic resonance (EPR) study of free radicals in irradiated zinc poly methacrylate

    International Nuclear Information System (INIS)

    We report the analysis of the X-band EPR spectrum of the free radical species formed in Zn(II) polymethacrylate (Zn(II) PMA), after degradation was induced in this polymer by 60Co γ- radiation at room temperature. We begin by describing the synthesis and characterization of our samples and its polymerization before applying them several doses to induce degradation. Doses from 10 to 100 kGy in steps of 10 kGy were applied to the samples. At 10 kGy dose, the EPR spectrum shows the superimposed spectra of two species, namely: a typical pattern of an axially symmetrical singlet and a broad symmetric single line. The former can be attributed to peroxide radicals. After applying further doses, the EPR spectra of the samples display a series of superimposed lines on top of the mentioned axial singlet and the broad line. In these spectra, we recognize three sets of lines: a weak doublet, a quartet and quintet in addition to the already detected axially symmetrical line and the broad singlet. These can be assigned to scission radicals trapped in the polymeric matrix. - Highlights: • We describe the synthesis and characterization of Zn(II) PMA and its polymerization. • Degradation was induced in this polymer by 60Co γ- radiation at room temperatura. • We report the analysis of the X-band EPR spectrum of the free radicals formed. • EPR spectrum of the degraded polymer shows a superimposed spectra of 5 species. • These are assigned to peroxide and scission radicals trapped in the polymer matrix

  15. EPR Methods for Biological Cu(II): L-Band CW and NARS

    Science.gov (United States)

    Bennett, Brian; Kowalski, Jason

    2016-01-01

    Copper has many roles in biology that involve the change of coordination sphere and/or oxidation state of the copper ion. Consequently, the study of copper in heterogeneous environments is an important area in biophysics. EPR is a primary technique for the investigation of paramagnetic copper, which is usually the isolated Cu(II) ion, but sometimes as Cu(II) in different oxidation states of multi-transition ion clusters. The gross geometry of the coordination environment of Cu(II) can often be determined from a simple inspection of the EPR spectrum, recorded in the traditional X-band frequency range (9 – 10 GHz). Identification and quantitation of the coordinating ligand atoms, however, is not so straightforward. In particular, analysis of the superhyperfine structure on the EPR spectrum, to determine the number of coordinated nitrogen atoms, is fraught with difficulty at X-band, despite the observation that the overwhelming number of EPR studies of Cu(II) in the literature have been carried out at X-band. Greater reliability has been demonstrated at S-band (3 – 4 GHz), using the low-field parallel (gz) features. However, analysis relies on clear identification of the outermost superhyperfine line, which has the lowest intensity of all the spectral features. Computer simulations have subsequently indicated that the much more intense perpendicular region of the spectrum can be reliably interpreted at L-band (2 GHz). The present work describes the development of L-band EPR of Cu(II) into a routine method, that is applicable to biological samples. PMID:26478491

  16. Application of EPR spectroscopy to the examination of pro-oxidant activity of coffee.

    Science.gov (United States)

    Krakowian, Daniel; Skiba, Dominik; Kudelski, Adam; Pilawa, Barbara; Ramos, Paweł; Adamczyk, Jakub; Pawłowska-Góral, Katarzyna

    2014-05-15

    Free radicals present in coffee may be responsible for exerting toxic effects on an organism. The objectives of this work were to compare free radicals properties and concentrations in different commercially available coffees, in solid and liquid states, and to determine the effect of roasting on the formation of free radicals in coffee beans of various origins. The free radicals content of 15 commercially available coffees (solid and liquid) was compared and the impact of processing examined using electron paramagnetic resonance (EPR) spectroscopy at X-band (9.3 GHz). First derivative EPR spectra were measured at microwave power in the range of 0.7-70 mW. The following parameters were calculated for EPR spectra: amplitude (A), integral intensity (I), and line-width (ΔBpp); g-Factor was obtained from resonance condition. Our study showed that free radicals exist in green coffee beans (10(16) spin/g), roasted coffee beans (10(18) spin/g), and in commercially available coffee (10(17)-10(18) spin/g). Free radical concentrations were higher in solid ground coffee than in instant or lyophilised coffee. Continuous microwave saturation indicated homogeneous broadening of EPR lines from solid and liquid commercial coffee samples as well as green and roasted coffee beans. Slow spin-lattice relaxation processes were found to be present in all coffee samples tested, solid and liquid commercial coffees as well as green and roasted coffee beans. Higher free radicals concentrations were obtained for both the green and roasted at 240 °C coffee beans from Peru compared with those originating from Ethiopia, Brazil, India, or Colombia. Moreover, more free radicals occurred in Arabica coffee beans roasted at 240 °C than Robusta. EPR spectroscopy is a useful method of examining free radicals in different types of coffee. PMID:24423509

  17. Correlation of the EPR properties of perchlorotriphenylmethyl radicals and their efficiency as DNP polarizers.

    Science.gov (United States)

    Banerjee, Debamalya; Paniagua, Juan Carlos; Mugnaini, Veronica; Veciana, Jaume; Feintuch, Akiva; Pons, Miquel; Goldfarb, Daniella

    2011-11-01

    Water soluble perchlorinated trityl (PTM) radicals were found to be effective 95 GHz DNP (dynamic nuclear polarization) polarizers in ex situ (dissolution) (13)C DNP (Gabellieri et al., Angew Chem., Int. Ed. 2010, 49, 3360). The degree of the nuclear polarization obtained was reported to be dependent on the position of the chlorine substituents on the trityl skeleton. In addition, on the basis of the DNP frequency sweeps it was suggested that the (13)C NMR signal enhancement is mediated by the Cl nuclei. To understand the DNP mechanism of the PTM radicals we have explored the 95 GHz EPR characteristics of these radicals that are relevant to their performance as DNP polarizers. The EPR spectra of the radicals revealed axially symmetric g-tensors. A comparison of the spectra with the (13)C DNP frequency sweeps showed that although the solid effect mechanism is operational the DNP frequency sweeps reveal some extra width suggesting that contributions from EPR forbidden transitions involving (35,37)Cl nuclear flips are likely. This was substantiated experimentally by ELDOR (electron-electron double resonance) detected NMR measurements, which map the EPR forbidden transitions, and ELDOR experiments that follow the depolarization of the electron spin upon irradiation of the forbidden EPR transitions. DFT (density functional theory) calculations helped to assign the observed transitions and provided the relevant spin Hamiltonian parameters. These results show that the (35,37)Cl hyperfine and nuclear quadrupolar interactions cause a considerable nuclear state mixing at 95 GHz thus facilitating the polarization of the Cl nuclei upon microwave irradiation. Overlap of Cl nuclear frequencies and the (13)C Larmor frequency further facilitates the polarization of the (13)C nuclei by spin diffusion. Calculation of the (13)C DNP frequency sweep based on the Cl nuclear polarization showed that it does lead to an increase in the width of the spectra, improving the agreement with the

  18. Foco Nasmyth para el telescopio 2,15mts. de CASLEO

    Science.gov (United States)

    Casagrande, A. R.

    En principio, este proyecto intenta lograr el mayor aprovechamiento posible del instrumental que se dispone, buscando la manera de optimizar y hacer más eficiente el servicio que brinda el CASLEO a la comunidad astronómica. El mismo consiste en utilizar dispositivos ya existentes en el telescopio, y darle una utilidad. Tal es el caso del camino óptico destinado al foco Coude. Si tenemos en cuenta que disponemos de un tercer espejo Coude, con todos sus mecanismos automatizados, (actualmente sin uso), una distancia apropiada del plano focal, el espacio y el lugar físico necesario para instalar un periférico, es posible la habilitación de un foco Nasmyth en el telescopio 2,15mts. El hecho de contar con este nuevo foco, redundará en importantes beneficios. En primer lugar, posibilitará la observación, casi simultánea, con dos instrumentos. Otro aspecto a tener en cuenta, es que disminuirá el frecuente cambio del instrumental periférico, motivo este que degrada su ideal puesta a punto. Por último, también de interés, es de destacar su escaso costo de ejecución.

  19. Effect of UV irradiation on free radicals in synthetic melanin and melanin biopolymer from Sepia officinalis – EPR examination

    OpenAIRE

    Zdybel Magdalena; Pilawa Barbara

    2015-01-01

    Free radicals in synthetic melanin and melanin from Sepia officinalis were studied by electron paramagnetic resonance (EPR) spectroscopy. The effect of time of ultraviolet (UV) irradiation on free radicals in these melanins was tested. The samples were exposed to UV during 15, 30, and 60 minutes. EPR spectra were measured with microwaves from an X-band (9.3 GHz) in the range of microwave power of 2.2–70 mW. The performed EPR examinations indicate that high concentrations (~1021–1022 spin/g) o...

  20. Modelo conceptual de datos difusos de triaje para emergencia hospitalaria representado con FuzzyEER

    Directory of Open Access Journals (Sweden)

    Wuilfredo Rangel

    2010-05-01

    Full Text Available El triaje de emergencia persigue desarrollar el proceso de valorización clínica preliminar para ordenar los pacientes según el nivel de urgencia o gravedad, antes de la atención médica, de forma que en una condición de saturación del servicio o disminución de recursos, los pacientes más graves sean tratados con prioridad. Un proceso de triaje presenta un alto grado de imprecisión o incertidumbre al momento de expresar el estado de salud de un paciente, en consecuencia puede haber dificultad y riesgo en la clasificación de las urgencias. En los servicios de emergencias de loshospitales públicos venezolanos, en especial el servicio de emergencia del Hospital Universitario de Caracas (HUC, seha evidenciado un incremento en el número de casos que se atienden, siendo una constante la saturación del servicio, lo cual imposibilita que los pacientes con prioridad de atención, sean tratados más rápidamente de forma oportuna y eficaz. En este trabajo se propone un modelo conceptual de datos difuso de triaje para el sector salud venezolano basado en el proceso de triaje hospitalario de la Sociedad Venezolana de Medicina de Emergencia y Desastres (SVMED, ya que un modelo de datos que contemple la representación de atributos difusos puede representar de mejor forma los requerimientos del sistema. El modelo propuesto utiliza la notación Entidad Relación con elementos difusos (FuzzyEER para la representación de las entidades y atributos con imprecisión. Dicho modelo será la base de un sistema automatizado de triaje que hará uso del lenguaje de consultas difusas FSQL (Fuzzy SQL.

  1. Projects of Iberdrola Engineering and Construction on the Flamanville 3 EPR; Proyectos de Iberdrola Ingenieria y construccion en el EPR de Flamanville 3

    Energy Technology Data Exchange (ETDEWEB)

    Zornoza, J.; Dumas, H.; Sesma, J. L.; Cubian, B.; Diaz, J. I.

    2013-06-01

    Iberdrola Engineering and Construction is participating during the last 5 years in 5 projects on the Flamanville 3 EPR, both in the nuclear island and conventional island and the pump house. These projects represent a challenge from the technical point of view due to the high requirements applicable to the project because of the experience feedback of the operator EDF and of compliance with new regulations that have emerged since the completion of the last nuclear power station in France. This paper presents the description of these projects, as well as its current status. (Author)

  2. Comparative EPR Examination of Gentamicin, Kanamycin and Netilmicin Effects on Free Radicals in DOPA-Melan

    International Nuclear Information System (INIS)

    Free radical properties of DOPA-melanin and its complexes with gentamicin, kanamycin and netilmicin were studied by the use of electron paramagnetic resonance spectroscopy at Xband (9.3 GHz). Melanins demonstrate stable paramagnetism and ability to drugs binding. Interactions of melanins with aminoglycoside antibiotics are not well known so far. o-Semiquinone free radicals formed in melanin biopolymers may be responsible for toxic effects appearing during antibioticotherapy. In this work we compare changes in paramagnetic centers systems of DOPA-melanin - model eumelanin caused by binding of typical aminoglycoside antibiotics. DOPA-melanin was chosen for measurements, because it mainly exists in living organism. The EPR results for the individual drugs were presented in our earlier works. EPR measurements were performed by the use of EPR spectrometer with modulation of magnetic field 100 kHz produced by RADIOPA-Poznan. Microwave frequency was recorded. The first derivative EPR spectra were recorded with low microwave power 0.7 MW at room temperature. Free radical concentration, g-factor, and linewidths were determined. Ultramarine was used as a reference of concentration of paramagnetic centers. A ruby crystal permanently placed in the spectrometer cavity was the secondary reference. Area under the absorption curve was obtained by double integration of its first derivative. g-Factor was calculated from the resonance condition. The influence of microwave power in the range of 0.7-70 MW on EPR lines of DOPAmelanin and its complexes with the analysed antibiotics was tested. Changes of amplitudes and linewidths with increasing of microwave power were obtained. o-Semiquinone free radicals exist in all the studied melanin complexes. It was confirmed that aminoglycoside antibiotics generate additional o-semiquinone free radicals in melanin polymer. The relatively low amount of free radicals appears in melanin after complexing with netilmicin - an antibiotic which

  3. Characterization of the factors having an influence on the evolution of the EPR signal of irradiated alanine

    International Nuclear Information System (INIS)

    EPR/alanine dosimetry has been used by the LNHB (Laboratoire National Henri Becquerel) since many years for applied metrology. This technic is based on the measurement of the EPR signal of the free radicals induced in alanine by irradiation. The aim of this work is to characterize the factors having an influence on the evolution of the amplitude of the EPR signal of irradiated alanine to limit the uncertainties on the determination of the absorbed dose. The first step of this work has been the choice of the dosimeter. A bibliographic study completed by experiments on the response of alanine isomers to the dose and on its stability with time has lead us to choose L-α-alanine powder as dosimeter. The influence of the recording parameter of the spectrometer on the characteristics of the EPR spectrum has then been studied. This has enabled us to optimize the recording conditions of EPR spectra. As the angular anisotropy of the EPR signal limits the measurements reproducibility, an experimental protocol has been defined to solve this problem. The repeatability of the measurements has been enhanced by modifying the spectrometer and using an internal standard constituted of single crystals of CuSO4.5H2O. As the amplitude of the EPR signal is sensitive to the measurement temperature, a method of normalization of the results to 20 C has been determined. We have studied the influence of an irradiation parameter and of environmental parameters. We have shown that the EPR signal amplitude increases with irradiation temperature. The EPR signal amplitude and its evolution vary strongly with storage conditions (temperature and moisture) of the dosimeter before and after irradiation. The presence of moisture in alanine powder leads to a loss of signal amplitude. The dosimeters exposition to light also entails a loss of amplitude. Oxygen does not influence the EPR spectrum of alanine. We have noticed that the EPR signal amplitude of samples stored in absence of moisture increases

  4. The Employment Precariousness Scale (EPRES): psychometric properties of a new tool for epidemiological studies among waged and salaried workers

    OpenAIRE

    Vives Vergara, Alejandra, 1971-; Amable, Marcelo; Ferrer Mon??s, Montserrat; Moncada i Llu??s, Salvador, 1957-; Llorens Serrano, Clara; Muntaner, Carles; Benavides, Fernando G.; Benach, Joan

    2010-01-01

    Background: Despite the fact that labour market flexibility has resulted in an expansion of precarious employment in industrialized countries, to date there is limited empirical evidence about its health consequences. The Employment Precariousness Scale (EPRES) is a newly developed, theory-based, multidimensional questionnaire specifically devised for epidemiological studies among waged and salaried workers. Objective: To assess acceptability, reliability and construct validity of EPRES in a ...

  5. RosettaTMH: a method for membrane protein structure elucidation combining EPR distance restraints with assembly of transmembrane helices

    Directory of Open Access Journals (Sweden)

    Andrew Leaver-Fay

    2015-12-01

    Full Text Available Membrane proteins make up approximately one third of all proteins, and they play key roles in a plethora of physiological processes. However, membrane proteins make up less than 2% of experimentally determined structures, despite significant advances in structure determination methods, such as X-ray crystallography, nuclear magnetic resonance spectroscopy, and cryo-electron microscopy. One potential alternative means of structure elucidation is to combine computational methods with experimental EPR data. In 2011, Hirst and others introduced RosettaEPR and demonstrated that this approach could be successfully applied to fold soluble proteins. Furthermore, few computational methods for de novo folding of integral membrane proteins have been presented. In this work, we present RosettaTMH, a novel algorithm for structure prediction of helical membrane proteins. A benchmark set of 34 proteins, in which the proteins ranged in size from 91 to 565 residues, was used to compare RosettaTMH to Rosetta’s two existing membrane protein folding protocols: the published RosettaMembrane folding protocol (“MembraneAbinitio” and folding from an extended chain (“ExtendedChain”. When EPR distance restraints are used, RosettaTMH+EPR outperforms ExtendedChain+EPR for 11 proteins, including the largest six proteins tested. RosettaTMH+EPR is capable of achieving native-like folds for 30 of 34 proteins tested, including receptors and transporters. For example, the average RMSD100SSE relative to the crystal structure for rhodopsin was 6.1 ± 0.4 Å and 6.5 ± 0.6 Å for the 449-residue nitric oxide reductase subunit B, where the standard deviation reflects variance in RMSD100SSE values across ten different EPR distance restraint sets. The addition of RosettaTMH and RosettaTMH+EPR to the Rosetta family of de novo folding methods broadens the scope of helical membrane proteins that can be accurately modeled with this software suite.

  6. Analysis of two-player quantum games in an EPR setting using Clifford's geometric algebra.

    Science.gov (United States)

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

    2012-01-01

    The framework for playing quantum games in an Einstein-Podolsky-Rosen (EPR) type setting is investigated using the mathematical formalism of geometric algebra (GA). The main advantage of this framework is that the players' strategy sets remain identical to the ones in the classical mixed-strategy version of the game, and hence the quantum game becomes a proper extension of the classical game, avoiding a criticism of other quantum game frameworks. We produce a general solution for two-player games, and as examples, we analyze the games of Prisoners' Dilemma and Stag Hunt in the EPR setting. The use of GA allows a quantum-mechanical analysis without the use of complex numbers or the Dirac Bra-ket notation, and hence is more accessible to the non-physicist.

  7. Characteristics and economy of the European reactor of pressurized water (EPR)

    International Nuclear Information System (INIS)

    The high current costs of the fossil fuels, have propitiated that the industries of electric power generation in the world reconsider the nuclear option as medium of generation. In Europe, the more recently contracted nuclear power plant is that of Olkiluoto-III in Finland that waits it enters in operation at the end of 2009. The reactor that will be installed in this power plant will be a prototype of pressurized water reactor of the companies AREVA and EDF. In this work they are described the reactor EPR and the major components of the nuclear power plant as well as the main characteristics of safety and the flexibility of the operation of the EPR. The supposed costs reported in different sources of information are also described and calculated with information provided by the manufacturer company. (Author)

  8. Characterisation of nanohybrids of porphyrins with metallic and semiconducting carbon nanotubes by EPR and optical spectroscopy.

    Science.gov (United States)

    Cambré, Sofie; Wenseleers, Wim; Culin, Jelena; Van Doorslaer, Sabine; Fonseca, Antonio; Nagy, Janos B; Goovaerts, Etienne

    2008-09-15

    Single-walled carbon nanotubes (SWCNTs) are noncovalently functionalised with octaethylporphyrins (OEPs) and the resulting nanohybrids are isolated from the free OEPs. Electron paramagnetic resonance (EPR) spectroscopy of cobalt(II)OEP, adsorbed on the nanotube walls by pi-pi-stacking, demonstrates that the CNTs act as electron acceptors. EPR is shown to be very effective in resolving the different interactions for metallic and semiconducting tubes. Moreover, molecular oxygen is shown to bind selectively to nanohybrids with semiconducting tubes. Water solubilisation of the porphyrin/CNT nanohybrids using bile salts, after applying a thorough washing procedure, yields solutions in which at least 99% of the porphyrins are interacting with the CNTs. Due to this purification, we observe, for the first time, the isolated absorption spectrum of the interacting porphyrins, which is strongly red-shifted compared to the free porphyrin absorption. In addition a quasi-complete quenching of the porphyrin fluorescence is also observed. PMID:18712730

  9. EPR study of gamma irradiated DL-methionine sulfone single crystals

    Science.gov (United States)

    Karabulut, Bünyamin; Yıldırım, İlkay

    2015-12-01

    Electron paramagnetic resonance (EPR) study of gamma irradiated dl-2-amino-4-(Methylsulfonyl) butyric acid (dl-methionine sulfone, hereafter dl-ABA) single crystals and powder was performed at room temperature. It has been found that this compound indicates the existence of C. O2- and N. H2 radicals after γ-irradiation. While g and hyperfine splitting values for the N. H2 radical were observed, for the C. O2- radical, only the g factor was measured. The EPR spectra have shown that N. H2 radical has two groups each having two distinct sites and C. O2- radical has one site. The principal g and hyperfine values for all sites were analyzed.

  10. Entanglement Conservation, ER=EPR, and a New Classical Area Theorem for Wormholes

    CERN Document Server

    Remmen, Grant N; Pollack, Jason

    2016-01-01

    We consider the question of entanglement conservation in the context of the ER=EPR correspondence equating quantum entanglement with wormholes. In quantum mechanics, the entanglement between a system and its complement is conserved under unitary operations that act independently on each; ER=EPR suggests that an analogous statement should hold for wormholes. We accordingly prove a new area theorem in general relativity: for a collection of dynamical wormholes and black holes in a spacetime satisfying the null curvature condition, the maximin area for a subset of the horizons (giving the largest area attained by the minimal cross section of the multi-wormhole throat separating the subset from its complement) is invariant under classical time evolution along the outermost apparent horizons. The evolution can be completely general, including horizon mergers and the addition of classical matter satisfying the null energy condition. This theorem is the gravitational dual of entanglement conservation and thus consti...

  11. Crystal Structure and EPR Spectra of cis-Dioxo-molybdenum(Ⅴ) Complex with o-Aminophenol

    Institute of Scientific and Technical Information of China (English)

    LU,Xiao-Ming(鲁晓明); LU,Jing-Fen(卢景芬); MAO,Xi-An(毛希安)

    2002-01-01

    The paramagnetic cis-dioxo-molybdenum(V) complex,[NH2CH2CH2NH3]3[HNC6H4O)2] was obtained by the reaction of tetra-butyl ammonium β-octamolybdate with oaminophenol and ethylenediamine in the mixed solvent of CH3OH and CH3CN, and characterized by IR,NMR,EPR spectroscopy and X-ray diffraction analysis .The determination of single crystal X-ray analysis revealed octahedral coordination withcis-dioxo o-aminophenol.The EPR spectra of both the complex and flavoenzyme show similarly.Thus it suggests that the complex anion[MovO2(HNC6H49)2]3-and flavoenzyme have related structure feature.

  12. DTA/TG, IR, EPR and XPS studies of some praseodymium(III) tungstates

    International Nuclear Information System (INIS)

    The praseodymium(III) tungstates (Pr2W2O9 and Pr2WO6) have been prepared as polycrystalline powders by thermal treatments of Pr6O11/WO3 mixtures in air. It was found the existence of only two polymorphic modification of Pr2W2O9. The low-temperature polymorph of Pr2W2O9 undergoes reversible polymorphic transition at 1390 K. Pr2W2O9 melts incongruently at 1462 K. Low-temperature modification of Pr2WO6 is thermally stable up to 1773 K. EPR spectra had shown weak only interactions between tungstate W5+ ions that were confirmed also by XPS measurements. Hyperfine structure of W4+ ions was also recognized. The spectra characteristics for Pr4+ ions were not observed both in EPR and XPS experiments.

  13. EPR and DNP Properties of Certain Novel Single Electron Contrast Agents Intended for Oximetric Imaging

    DEFF Research Database (Denmark)

    Ardenkjær-Larsen, J. H.; Laursen, I; Leunbach, I.;

    1998-01-01

    Parameters of relevance to oximetry with Overhauser magnetic resonance imaging (OMRI) have been measured for three single electron contrast agents of the triphenylmethyl type. The single electron contrast agents are stable and water soluble. Magnetic resonance properties of the agents have been...... examined with electron paramagnetic resonance (EPR), nuclear magnetic resonance (NMR), and dynamic nuclear polarization (DNP) at 9.5 mT in water, isotonic saline, plasma, and blood at 23 and 37°C. The relaxivities of the agents are about 0.2–0.4 mM−1s−1and the DNP enhancements extrapolate close...... to the dipolar limit. The agents have a single, narrow EPR line, which is analyzed as a Voigt function. The linewidth is measured as a function of the agent concentration and the oxygen concentration. The concentration broadenings are about 1–3 μT/mM and the Lorentzian linewidths at infinite dilution are less...

  14. Dating sediment deposits on Montalvanian carvings using EPR and TL methods

    Energy Technology Data Exchange (ETDEWEB)

    Sastry, M.D.; Sullasi, Henry S.L. E-mail: hsullasi@dfn.if.usp.br; Camargo, Fabiola; Watanabe, Shigueo; Prous, Andre P.P.; Silva, Martha M.C

    2004-01-01

    About 30 years ago a rock shelter with engravings by early settlers was found at Montalvania, northern end of state of Minas Gerais, Brazil. Lower part of engravings was covered with thin deposit of calcite mixed with quartz grains, due to occasional flood. This mixture of two minerals was dated by thermoluminescence and electron paramagnetic resonance using in both cases, additive method. The accumulated dose D{sub AC}, that is, natural radioactivity and cosmic rays radiation dose that induces TL and EPR signal intensity has been found to be around 50 Gy both by TL and EPR methods. The annual radiation dose rate was estimated to be about 1.027 mGy/a from knowledge of uranium, thorium and potassium content determined by inductively coupled plasma-mass spectrometer system. The age of this calcite plus quartz deposits was estimated to be about 50 ka.

  15. An EPR and antioxidant efficiency study of the pinebark phenolic extracts pycnogenol (R) and endogenol

    International Nuclear Information System (INIS)

    Full text: Pycnogenol (R) is a phenolic extract of French Maritime Pine bark: the name was invented by Jack Masquelier, a noted researcher into phenolic antioxidant activity, but is now owned by the Company Horphag. Endogenol is a New Zealand phenolic extract of Pinus Radiata bark: both products are sold as dietary supplements. EPR and antioxidant efficiency measurements were made on both. The EPR signal from Endogenol was stronger than that from Pycnogenol (R), but the antioxidant efficiencies were almost the same, at slightly more than 50% that of vitamin C as measured by the technique used, already described by these same authors in: I. Cheah et al, ( 2003), AIM- digest 12,(l) 14-15. It is not only useful, but necessary to check such dietary supplements for their claimed contents and actions. Samples were kindly supplied by the manufacturers

  16. Investigations in quantum games using EPR-type set-ups

    CERN Document Server

    Iqbal, A

    2006-01-01

    Research in quantum games has flourished during recent years. However, it seems that opinion remains divided about their true quantum character and content. For example, one argument says that quantum games are nothing but 'disguised' classical games and that to quantize a game is equivalent to replacing the original game by a different classical game. The present thesis contributes towards the ongoing debate about quantum nature of quantum games by developing two approaches addressing the related issues. Both approaches take Einstein-Podolsky-Rosen (EPR)-type experiments as the underlying physical set-ups to play two-player quantum games. In the first approach, the players' strategies are unit vectors in their respective planes, with the knowledge of coordinate axes being shared between them. Players perform measurements in an EPR-type setting and their payoffs are defined as functions of the correlations, i.e. without reference to classical or quantum mechanics. Classical bimatrix games are reproduced if th...

  17. AC susceptibility and EPR investigations of superspin dynamics in magnetite nanoparticles

    Science.gov (United States)

    Price, Alex D.

    In this investigation we use two complementary techniques to distinguish between superparamagnetic blocking (SPB) and superspin-glass (SSG) freezing phenomena in magnetite nanoparticles. While these manifestations of the superspin dynamics are fundamentally different, they have similar "signatures", especially in dc-magnetization experiments. Even if ac-susceptibility measurements are employed, careful use of mathematical models to analyze the data are needed to uncover which type of phenomena (SPB or SSG freezing) occurs within the material. Yet, by utilizing electron paramagnetic resonance (EPR) on a 10 nm Fe3O4 nano-powder as well as on a ferrofluid (based on the same nanoparticle ensemble) we found a very distinct difference in the absorption spectra between the two samples, which indicates markedly different EPR signatures from SPB and SSG freezing behaviors.

  18. EPR and UV-vis studies of biomimetic complexes of molybdoenzyme and tungstoenzyme

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The Mo(Ⅴ) and W(Ⅵ) complexes of (NH3CH2- CH2NH2)3[Mo(Ⅴ)O2(OC6H4O)2] (1), (NH3CH2CH2NH2)2.5 [Mo(Ⅴ) 0.5W(Ⅵ)0.5O2(OC6H4O)2] (2) and (NH3CH2CH2NH2)2- [W(Ⅵ)O2(OC6H4O)2] (3) were synthesized by choosing catechol ligand which shows a good reductive property and taking advantage of EMo > EW. Their EPR and UV-vis spectra were compared with the oxidized UV-vis spectra of xanthine dehydrogenase from chicken liver and xanthine oxidase from milk and the EPR spectrum of flavoenzyme from milk.

  19. Correlated four-component EPR g-tensors for doublet molecules

    DEFF Research Database (Denmark)

    Vad, M.S.; Pedersen, M.N.; Nørager, A.;

    2013-01-01

    configuration interaction wave functions in the DIRAC program package. We find that the correlation effects on the g-tensors can be sufficiently well described with manageable basis sets of triple-zeta quality and manageable configuration spaces. The new fully relativistic EPR module in DIRAC should be useful......The first correlated ab initio four-component calculations of electron paramagnetic resonance (EPR) g-tensors for doublet radicals are reported. We have implemented a first-order degenerate perturbation theory approach based on the four-component Dirac-Coulomb Hamiltonian and fully relativistic...... for benchmarking density functional theory approaches, however, with future optimization of the code we believe it will also be useful for applications. © 2013 AIP Publishing LLC....

  20. Mechanical design and analysis for a EPR first wall/blanket/shield system

    International Nuclear Information System (INIS)

    Continuing studies are in progress at ANL to expand upon the design of a first wall/blanket/shield FW/B/S system and power conversion for a tokamak type Experimental Power Reactor (EPR). The FW/B/S system has evolved from an earlier design for a low beta, circular cross section plasma (major radius = 6 m) to one for a higher beta elongated plasma with a 4.7 m major radius. Basic mechanical design and layout features of the old and new EPR designs showing some of the more important design developments are given. These developments are aimed at simplifying the design, reducing the costs and in addition, improving the plant thermal efficiency and overall maintainability. In the area of the reactor blanket, significant thermal hydraulic and stress analysis have been performed to substantiate the integrity of the chosen concept. This paper deals with the discussion of these improved features

  1. Manufacturing of nozzle shell with integral flange for EPR pressure vessel and its properties

    International Nuclear Information System (INIS)

    The 1600 MWe EPR (European Pressurized Water Reactor) with more improved reliability, operation, maintenance and economics has been developed to achieve higher output and longer lifetime, comparing with conventional nuclear power plants, and the first EPR was introduced in Olkiluoto Unit 3, Finland Unit 5. The integrated mono-block design was applied for the nozzle shell flange instead of the welded conventional flange and nozzle shell. A 600-ton ingot was required for this part because of the set-on type nozzles. Manufacturing of the first nozzle shell with integral flange in the world was completed successfully taking eleven months. This report introduces the manufacturing technology and properties of nozzle shell with integral flange. (T. Tanaka)

  2. Mechanical design and analysis for a EPR first wall/blanket/shield system

    Energy Technology Data Exchange (ETDEWEB)

    Stevens, H.C.; Misra, B.; Youngdahl, C.K.

    1977-01-01

    Continuing studies are in progress at ANL to expand upon the design of a first wall/blanket/shield FW/B/S system and power conversion for a tokamak type Experimental Power Reactor (EPR). The FW/B/S system has evolved from an earlier design for a low beta, circular cross section plasma (major radius = 6 m) to one for a higher beta elongated plasma with a 4.7 m major radius. Basic mechanical design and layout features of the old and new EPR designs showing some of the more important design developments are depicted. These developments are aimed at simplifying the design, reducing the costs and, in addition, improving the plant thermal efficiency and overall maintainability. In the area of the reactor blanket, significant thermal hydraulic and stress analysis have been performed to substantiate the integrity of the chosen concept. This paper deals with the discussion of these improved features.

  3. Analysis of two-player quantum games in an EPR setting using Clifford's geometric algebra.

    Directory of Open Access Journals (Sweden)

    James M Chappell

    Full Text Available The framework for playing quantum games in an Einstein-Podolsky-Rosen (EPR type setting is investigated using the mathematical formalism of geometric algebra (GA. The main advantage of this framework is that the players' strategy sets remain identical to the ones in the classical mixed-strategy version of the game, and hence the quantum game becomes a proper extension of the classical game, avoiding a criticism of other quantum game frameworks. We produce a general solution for two-player games, and as examples, we analyze the games of Prisoners' Dilemma and Stag Hunt in the EPR setting. The use of GA allows a quantum-mechanical analysis without the use of complex numbers or the Dirac Bra-ket notation, and hence is more accessible to the non-physicist.

  4. EPR-assessment of soils radiation doses for Semipalatinsk test site's north-east trace

    International Nuclear Information System (INIS)

    The dose loads are an important characteristics of potential damage assessment for health of population suffered from nuclear incidents. Technique of retrospective dosimetry allows to evaluate of these loads, if to find in the soils samples the radiation detector - for example, some mineral - in which in the locality conditions the radiation defects are accumulating and keeping and giving the EPR signal. In the paper the results of searching of such detector to Semipalatinsk test site soils samples are expounded.The samples were taken along the north-east trace of radioactive cloud (step ∼2 km) on the distance 0.7-112 km from the air thermonuclear explosion epicenter. Te EPR performances were studied on the ESP 300E spectrometer of Brucker company (Germany). The tested methodic is perspective for determination of dose loads of soils with integral irradiation dose does not exceeds 10-15 kGy

  5. Draft resolution aimed at creating an inquiry commission related to the EPR sector - Nr 1251

    International Nuclear Information System (INIS)

    This draft resolution is based on several problems and issues raised by the construction of the EPR reactor in Flamanville and dealing with the perspectives for this specific sector. The authors outline that the construction may finally take almost twice as long as initially foreseen, that the budget has been multiplied by two and a half, that the safety of this installation is still a matter of questions (notably for the control-command system, for the resistance to a plane crash, and with respect with lessons learned from the Fukushima accident), and that the involved partners (GDF Suez, ENEL, Centrica, Siemens) are becoming always more hesitant. They evoke the problems faced by other EPRs under construction in Finland and in China, and state that export perspectives seem to lead to a failure. The draft resolution proposes the creation of an inquiry commission to examine these issues

  6. Dating sediment deposits on Montalvanian carvings using EPR and TL methods

    Science.gov (United States)

    Sastry, M. D.; Sullasi, Henry S. L.; Camargo, Fabiola; Watanabe, Shigueo; Prous, André P. P.; Silva, Martha M. C.

    2004-01-01

    About 30 years ago a rock shelter with engravings by early settlers was found at Montalvânia, northern end of state of Minas Gerais, Brazil. Lower part of engravings was covered with thin deposit of calcite mixed with quartz grains, due to occasional flood. This mixture of two minerals was dated by thermoluminescence and electron paramagnetic resonance using in both cases, additive method. The accumulated dose DAC, that is, natural radioactivity and cosmic rays radiation dose that induces TL and EPR signal intensity has been found to be around 50 Gy both by TL and EPR methods. The annual radiation dose rate was estimated to be about 1.027 mGy/a from knowledge of uranium, thorium and potassium content determined by inductively coupled plasma-mass spectrometer system. The age of this calcite plus quartz deposits was estimated to be about 50 ka.

  7. SINGLE LOOP - MULTI GAP RESONATOR FOR WHOLE BODY EPR IMAGING OF MICE AT 1.2 GHZ

    Science.gov (United States)

    Petryakov, Sergey; Samouilov, Alexandre; Kesselring, Eric; Wasowicz, Tomasz; Caia, George L.; Zweier, Jay L.

    2009-01-01

    For whole body EPR imaging of small animals, typically low frequencies of 250–750 MHz have been used due to the microwave losses at higher frequencies and the challenges in designing suitable resonators to accommodate these large lossy samples. However, low microwave frequency limits the obtainable sensitivity. L-band frequencies can provide higher sensitivity, and have been commonly used for localized in vivo EPR spectroscopy. Therefore, it would be highly desirable to develop an L-band microwave resonator suitable for in vivo whole body EPR imaging of small animals such as living mice. A 1.2 GHz 16 gap resonator with inner diameter of 43 mm and 48 mm length was designed and constructed for whole body EPR imaging of small animals. The resonator has good field homogeneity and stability to animal induced motional noise. Resonator stability was achieved with electrical and mechanical design utilizing a fixed position double coupling loop of novel geometry, thus minimizing the number of moving parts. Using this resonator, high quality EPR images of lossy phantoms and living mice were obtained. This design provides good sensitivity, ease of sample access, excellent stability and uniform B1 field homogeneity for in vivo whole body EPR imaging of mice at 1.2 GHz. PMID:17625940

  8. Single loop multi-gap resonator for whole body EPR imaging of mice at 1.2 GHz

    Science.gov (United States)

    Petryakov, Sergey; Samouilov, Alexandre; Kesselring, Eric; Wasowicz, Tomasz; Caia, George L.; Zweier, Jay L.

    2007-09-01

    For whole body EPR imaging of small animals, typically low frequencies of 250-750 MHz have been used due to the microwave losses at higher frequencies and the challenges in designing suitable resonators to accommodate these large lossy samples. However, low microwave frequency limits the obtainable sensitivity. L-band frequencies can provide higher sensitivity, and have been commonly used for localized in vivo EPR spectroscopy. Therefore, it would be highly desirable to develop an L-band microwave resonator suitable for in vivo whole body EPR imaging of small animals such as living mice. A 1.2 GHz 16-gap resonator with inner diameter of 42 mm and 48 mm length was designed and constructed for whole body EPR imaging of small animals. The resonator has good field homogeneity and stability to animal-induced motional noise. Resonator stability was achieved with electrical and mechanical design utilizing a fixed position double coupling loop of novel geometry, thus minimizing the number of moving parts. Using this resonator, high quality EPR images of lossy phantoms and living mice were obtained. This design provides good sensitivity, ease of sample access, excellent stability and uniform B1 field homogeneity for in vivo whole body EPR imaging of mice at 1.2 GHz.

  9. EPR method for investigation and diagnosis materials promising for quantum electronics (PbGa2S4, ZnSe)

    International Nuclear Information System (INIS)

    Electron paramagnetic resonance (EPR) spectra of rare-earth Dy3+ and Ce3+ ions in lead thiogallate PbGa2S4 single crystals were discovered and investigated. EPR spectra were studied in X-band in the temperature range 4–30 K. Parameters of spin Hamiltonian of EPR spectra of Dy3+ and Ce3+ ions in PbGa2S4 single crystals were calculated. It was set that dysprosium and cerium ions replace lead ions in crystal lattice. Also we carried out a diagnosis of ZnSe crystals doped with different rare-earth and transition metal ions. It was shown that due to diffusion of transition elements of Cr3+, Co2+ or Fe3+ along with the working admixture in the diffusion layer the EPR spectra of related admixtures are detected. The EPR diagnosis of these admixtures can be used in the development of modes, allowing minimizing the concentration of related admixtures, worsening the performance of laser materials. It was found that diffusion of Cr, Co and Fe transition metal ions leads to admixture of Mn ions. The EPR signals of Mn and Co are proposed as the ideal markers to control the crystal structure of the diffusion active layer

  10. Effect of absorbed dose and storage length on electron paramagnetic resonance (EPR) signal strength in irradiated alfalfa seeds

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A kind of alfalfa seeds was irradiated by 1, 2, 3, 4 and 5 kGy at a dose rate of 6.288 kGy. h-1 in a self-shielded irradiator of 137Cs gamma rays. The EPR spectra, which were measured subsequently between 0.3401and 0.3501 T, showed that there was a direct proportional relationship between the EPR signal strength of free radicals produced by gamma irradiation in the alfalfa seeds and absorbed dose. The first derivative EPR spectra of the alfalfa seeds were very clear and easy to identify. However, the EPR signal strength of the peak-to-peak amplitude decreased rapidly and most of them decayed beyond 50% within 3 days after the seeds were irradiated. It tended to stabilize after half a month since the seeds were irradiated. The differences of the EPR signal strength between the irradiated and unirradiated alfalfa seeds still remained. All seeds were stored at ambient temperature for more than 3months. Therefore, using EPR spectrometry technique to measure free radicals in alfalfa seeds as a means to determine whether the seeds have been irradiated or not is feasible, relatively fast and simple.

  11. An in vitro L-band EPR study with whole human teeth in a surface coil resonator

    International Nuclear Information System (INIS)

    L-band EPR measurements were done in vitro on extracted human teeth with the objective to evaluate the feasibility of retrospective in vivo EPR dosimetry. In a recent study, the relative contributions of individual tooth components (enamel, crown dentin and root) to the total response of a whole tooth inside an L-band surface coil resonator was investigated. In the present work, the gamma-dose response curves were evaluated for different EPR signal evaluation methods, using 35 whole teeth with absorbed doses in the range 1-100 Gy. The paper reports on the first attempt to deconvolute the single composite L-band EPR line in components due to CO2- and native radicals. The L-band EPR spectrum of teeth could be approximated by combining powder-simulated spectra of orthorhombic and quasi-axial signals of the CO2- radical and an isotropic signal of the native radicals. Among the applied EPR signal evaluation methods, the evaluation by spectrum deconvolution revealed the lowest detection limit for absorbed dose. A detection limit of about 0.5 Gy was estimated for the currently available L-band equipment

  12. Effect of absorbed dose and storage length on electron paramagnetic resonance (EPR) signal strength in irradiated alfalfa seeds

    International Nuclear Information System (INIS)

    A kind of alfalfa seeds was irradiated by 1, 2, 3, 4 and 5 kGy at a dose rate of 6.288 kGy·h-1 in a self-shielded irradiator of 137Cs gamma rays. The EPR spectra, which were measured subsequently between 0.3401 and 0.3501 T, showed that there was a direct proportional relationship between the EPR signal strength of free radicals produced by gamma irradiation in the alfalfa seeds and absorbed dose. The first derivative EPR spectra of the alfalfa seeds were very clear and easy to identify. However, the EPR signal strength of the peak-to-peak amplitude decreased rapidly and most of them decayed beyond 50% within 3 days after the seeds were irradiated. It tended to stabilize after half a month since the seeds were irradiated. the differences of the EPR signal strength between the irradiated and unirradiated alfalfa seeds still remained. All seeds were stored at ambient temperature for more than 3 months. Therefore, using EPR spectrometry technique to measure free radicals in alfalfa seeds as a means to determine whether the seeds have been irradiated or not is feasible, relatively fast and simple. (authors)

  13. EPR investigation of N@C$_{70}$ in polycrystalline C$_{70}$ and single wall carbon nanotubes

    OpenAIRE

    Dinse, Klaus-Peter; Corzilius, Björn; Jakes, Peter; Weiden, Norbert; Agarwal, Suman

    2008-01-01

    Abstract Using multi frequency electron paramagnetic resonance (EPR) it was possible to determine the inherent fine structure (FS) interaction of nitrogen encapsulated in a C$_{70}$ cage. Confinement of N@C$_{70}$ in single wall carbon nanotubes (SWNT) of rather wide diameter does not significantly influence this value. The transition between isotropic molecular tumbling and immobilisation was found to occur at about 170~K in both matrices, indicating that the hindra...

  14. FTIR and EPR Studies of Nickel Substituted Nano structured Mn Zn Ferrite

    International Nuclear Information System (INIS)

    The spinel ferrite system is prepared by coprecipitation method. XRD analysis confirms the formation of ferrite phase in all the samples. The FTIR spectra of all the samples show two main absorption bands below 1000 cm−1. FTIR studies reveal cationic exchange between A site and B site. The magnetic moment calculated from EPR studies is lower when compared to the theoretical values. This confirms the existence of non collinear magnetic structure arising due to spin canting at B site.

  15. Ionizable Nitroxides for Studying Local Electrostatic Properties of Lipid Bilayers and Protein Systems by EPR

    Science.gov (United States)

    Voinov, Maxim A.; Smirnov, Alex I.

    2016-01-01

    Electrostatic interactions are known to play one of the major roles in the myriad of biochemical and biophysical processes. In this Chapter we describe biophysical methods to probe local electrostatic potentials of proteins and lipid bilayer systems that is based on an observation of reversible protonation of nitroxides by EPR. Two types of the electrostatic probes are discussed. The first one includes methanethiosulfonate derivatives of protonatable nitroxides that could be used for highly specific covalent modification of the cysteine’s sulfhydryl groups. Such spin labels are very similar in magnetic parameters and chemical properties to conventional MTSL making them suitable for studying local electrostatic properties of protein-lipid interfaces. The second type of EPR probes is designed as spin-labeled phospholipids having a protonatable nitroxide tethered to the polar head group. The probes of both types report on their ionization state through changes in magnetic parameters and a degree of rotational averaging, thus, allowing one to determine the electrostatic contribution to the interfacial pKa of the nitroxide, and, therefore, determining the local electrostatic potential. Due to their small molecular volume these probes cause a minimal perturbation to the protein or lipid system while covalent attachment secure the position of the reporter nitroxides. Experimental procedures to characterize and calibrate these probes by EPR and also the methods to analyze the EPR spectra by least-squares simulations are also outlined. The ionizable nitroxide labels and the nitroxide-labeled phospholipids described so far cover an exceptionally wide pH range from ca. 2.5 to 7.0 pH units making them suitable to study a broad range of biophysical phenomena especially at the negatively charged lipid bilayer surfaces. The rationale for selecting proper electrostatically neutral interface for calibrating such probes and example of studying surface potential of lipid bilayer is

  16. Investigation of signal fading in lithium formate EPR dosimeters using a new sensitive method

    OpenAIRE

    Adolfsson, Emelie; Karlsson, Mattias; Alm Carlsson, Gudrun; Carlsson Tedgren, Åsa; Lund, Eva; Olsson, Sara; Gustafsson, Håkan

    2012-01-01

    The aim of this study was to investigate signal fading in lithium formate electron paramagnetic resonance (EPR) dosimeters used for clinical applications in radiotherapy. A new experimental method for determination of signal fading, designed to resolve small changes in signal from slowly decaying unstable radicals, was used. Possible signal fading in lithium formate due to different storage temperatures was also tested. Air humidity was kept at a constant level of 33% throughout the experimen...

  17. EPR spectroscopy for the detection of foods treated with ionising radiation

    International Nuclear Information System (INIS)

    The advantage of electron paramagnetic resonance spectroscopy (EPR or ESR) as a tool for the control of irradiated food lies in its sensitivity and accuracy. Ionising radiation produces, in irradiated materials, paramagnetic species of different kinds, i.e. radicals, radical-ions and paramagnetic centres, which can be measured by EPR but most of them are not stable enough to be used for the detection of irradiation. It is because radiation-induced paramagnetic species are thermodynamically less stable than surrounding molecules and take part in fast radiolytic reactions leading to the formation of final diamagnetic products that they are not detectable by the EPR method. Most of organic radicals produced by radiation in the liquid phase ae unstable but if the unpaired electron is incorporated into the complex polymeric system as in peptides and polysaccharides and is structurally isolated from the water, its stability is markedly increased. Since 1954 it is known that ionising radiation produces paramagnetic entities in biological materials, cells and tissues and some are stable enough to be observed by EPR spectroscopy at room temperature. The present paper describes and discusses that part of results obtained by this group during the period of ADMIT activity (1989-94) which are original and may be useful to those who will be working in the near future on the development of uniform control systems for the detection of irradiated food. The intention was to focus attention on these facts and data which influence the certainty of the detection in both positive and negative manner. (author)

  18. EPR studies on melaminium hexachlorodicuprate - a one-dimensional dimeric copper (II) chain system

    International Nuclear Information System (INIS)

    X-band EPR studies of the monoclinic crystal melaminium hexachlorodicuprate (MHCC) constituted of ladder-like chains of copper (II) dimers (S 1) running parallel to the a-axis are carried out in the temperature interval 77-295 K. Spectra recorded in the two crystallographic planes (010) and (001) have revealed some features quite distinct from those of true dimeric compounds such as copper acetate monohydrate. Only a single line spectrum has been observed in all orientations of the single crystal. A large disparity was observed between the mean g-value (2.11) directly obtained from EPR measurements and that (2.21) derived from mean magnetic susceptibility data based on the 'mean field corrected dimer model' of Colombo et al (Colombo A, Menabue L, Motori A, Pellacani G C, Porzio W, Sandrolini F and Willet R D 1985 Inorg. Chem. 24 2900). EPR lineshape is Lorentzian in all directions of the crystal. The linewidth has appreciable anisotropy (1000-600 Oe). The observed angular variation of linewidth in the said crystallographic planes has been analysed on the basis of the anisotropic exchange theory of Ritter et al (Ritter M B, Drumheller J E, Kite T M, Snively L O and Emerson K 1983 Phys. Rev. 28 4949) suitably modified to be applicable in the present case of the S=1 1D system. The thermal dependence of EPR line intensity has also been investigated. It has been shown that the MHCC system is best described as an antiferromagnetic exchange coupled S=1 1D system. The presence of orthorhombic anisotropic symmetric exchange has also been confirmed. (author)

  19. Bismuth germanate as a perspective material for dielectric resonators in EPR spectroscopy.

    Science.gov (United States)

    Ivanov, Mikhail Y; Nadolinny, Vladimir A; Bagryanskaya, Elena G; Grishin, Yuriy A; Fedin, Matvey V; Veber, Sergey L

    2016-10-01

    High purity bismuth germanate (Bi4(GeO4)3, BGO) is proposed and implemented as an alternative material for dielectric EPR resonators. A significant improvement of the absolute sensitivity can be readily achieved by substituting the alumina insert (ring) by BGO-made one in commercially available X-band EPR probeheads. Four BGO dielectric inserts of 2, 3, 4 and 5mm inner diameter (ID) were made for comparison with standard 5mm inner diameter alumina insert. All inserts were introduced into commercial Bruker EPR resonator ER 4118X-MD-5W1, and their performance was investigated. The Q-values of empty resonators, B1 saturation curves and continuous wave EPR spectra of DPPH (2,2-diphenyl-1-picrylhydrazyl) were measured and analyzed in a temperature range 6-300K. BGO-made resonators were found superior in several important aspects. The background signals arising from BGO are much weaker compared to those of alumina at B=0-0.6T and T=6-300K; this is especially useful for measuring weak signals in the half-field region, as well as those near the central field. Moreover, mechanical properties of BGO allow easy fabrication of dielectric bodies having various shapes and sizes; in particular, small BGO resonators (e.g. ID=2 or 3mm) strongly enhance sensitivity for small samples due to increase of the filling factor. All these advantages have been also inspected in the pulse mode, proving that higher B1 fields and better filling factors can be achieved, contributing to the overall enhancement of the performance. PMID:27569694

  20. Using Linear Programming to Construct Better Criteria for Closing the Detection Loophole in Epr Experiments

    OpenAIRE

    Bigelow, James H.

    2008-01-01

    I formulate the problem of closing the detection loophole as a constrained optimization problem. Numerical methods can then be used to maximize the detector efficiency subject to the constraint that there exists a local realist explanation for the quantum correlations observed in the EPR experiment in question. Any detector efficiency larger than this maximum rules out all local realist explanations, and hence closes the detection loophole.

  1. Synthesis and EPR Characterization of Exohedrally Perfluoroalkylated Paramagnetic Lanthanum Metallofullerenes: A Fluorous Phase Approach

    Science.gov (United States)

    Tagmatarchis, Nikos; Taninaka, Atsushi; Shinohara, Hisanori; Prato, Maurizio

    2002-10-01

    A strategy to chemically derivatize the outer sphere of endohedral metallofullerenes by using a modern organic technique that utilizes a fluorous synthesis-partitioning approach has been developed. The newly synthesized materials were found to be paramagnetic species and were characterized by electron paramagnetic resonance spectroscopy (EPR), laser desorption time-of-flight spectrometry (LD-TOF) and electronic absorption spectroscopy (UV-VIS-NIR). The systematic study of exohedrally derivatized endohedral metallofullerenes should ultimately provide technologically intriguing novel nano-materials.

  2. L-026: EPR-First Responders: Action Guides Extinguishing Fire Brigades

    International Nuclear Information System (INIS)

    This conference will cover how and when to apply the Fire Brigades. Instructions and guidelines within the IAEA-EPR-First Responders to be used to guide the fire fighting brigade in a radiological emergency response to radioactive material in a manner that will minimize risks while performing the task. It will take into consideration the use of several types of monitoring equipment such as oxygen level meters, sight explosive, chemical meters and radiation detectors

  3. Complex time dependence of the EPR signal of irradiated L-α-alanine

    International Nuclear Information System (INIS)

    Measurements of the EPR signal amplitude of γ-irradiated L-α-alanine with use of an adjacent reference sample have revealed variations in the signal intensity within hours and days after irradiation. The character of the time dependence of the amplitude varies with dose and the amplitude changes reach 1-1.5%. This observation favors the hypothesis that irradiated alanine contains several paramagnetic centers. Usefulness of adjacent reference samples in alanine dosimetry is also demonstrated. (Author)

  4. PENGARUH ENERGI-PROTEIN RASIO (EPR) RANSUM LOKAL YANG BERBEDA TERHADAP PERFORMA DAN BERAT KARKAS BROILER

    OpenAIRE

    Nompo, Syamsuddin; Pantjawidjaja, Suhendra

    2011-01-01

    Latterly most published research concerning the poultry production is an increasingly important part of agriculture, but it also were the highest producers of ammonia gas (NH3) emissions of all domesticated species. One potential strategy for reducing NH3 emission is by formulating diets to precisely meet the nutrient needs. The objective of this study was to determine the effects of energy-protein ratio (EPR) using different local diets on performance and carcass weight of broilers. A total ...

  5. Relativistic EPR-type experiments for photons in the background of reducible representation HOLA algebras

    OpenAIRE

    Wrzask, Klaudia

    2015-01-01

    Relativistic EPR-type experiments for photons in the background of reducible representation algebras are discussed. A model for the four Bell states, such that maintains maximally correlated in two bases: linear and circular in all reference frames is developed. Relativistic correlation functions are derived for two cases: when the detectors are transformed under Lorentz transformation in such a way that they still remain in the same reference frame and when just one of the detectors is trans...

  6. Optimisation of an EPR dosimetry system for robust and high precision dosimetry

    International Nuclear Information System (INIS)

    Clinical applications of electron paramagnetic resonance (EPR) dosimetry systems demand high accuracy causing time consuming analysis. The need for high spatial resolution dose measurements in regions with steep dose gradients demands small sized dosimeters. An optimization of the analysis was therefore needed to limit the time consumption. The aim of this work was to introduce a new smaller lithium formate dosimeter model (diameter reduced from standard diameter 4.5 mm to 3 mm and height from 4.8 mm to 3 mm). To compensate for reduced homogeneity in a batch of the smaller dosimeters, a method for individual sensitivity correction suitable for EPR dosimetry was tested. Sensitivity and repeatability was also tested for a standard EPR resonator and a super high Q (SHQE) one. The aim was also to optimize the performance of the dosimetry system for better efficiency regarding measurement time and precision. A systematic investigation of the relationship between measurement uncertainty and number of readouts per dosimeter was performed. The conclusions drawn from this work were that it is possible to decrease the dosimeter size with maintained measurement precision by using the SHQE resonator and introducing individual calibration factors for dosimeter batches. It was also shown that it is possible reduce the number of readouts per dosimeter without significantly decreasing the accuracy in measurements. - Highlights: • A lithium formate dosimetry system was optimized for accurate dose determinations. • Smaller-sized dosimeters for measurements in dose gradient regions was developed. • Individual sensitivity calibration was introduced for EPR dosimetry. • Measurement precision versus measurement time was evaluated

  7. Temperature dependent electron paramagnetic resonance (EPR) of SrZrO{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, Santosh K., E-mail: santufrnd@gmail.com [Radiochemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai (India); Pathak, Nimai [Radiochemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai (India); Ghosh, P.S. [Materials Science Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Rajeshwari, B. [Radiochemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai (India); Materials Science Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Natarajan, V. [Materials Science Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Kadam, R.M. [Radiochemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai (India)

    2015-10-01

    SrZrO{sub 3} (SZO), a distorted perovskite was synthesized using gel-combustion route employing citric acid as a fuel and ammonium nitrate as oxidizer followed by characterization using X-ray diffraction (XRD) and electron paramagnetic resonance (EPR). Purity of the sample is confirmed by inductively coupled plasma atomic emission spectroscopy (ICP-AES) analysis. Broadening and shift of the resonance field position in EPR spectrum to the lower field was observed as the temperature is lowered; which is the characteristic of ferromagnetic resonance spectra. The value of Curie–Weiss temperature obtained for SZO particles is 8.7 K. The positive sign of the Curie–Weiss temperature indicates that some of the spins are ferromagnetically coupled in this sample. Theoretical investigation using density functional theory (DFT) calculation revealed that Vacancy at zirconium site contribute maximum to the magnetic moment. - Highlights: • Gel-combustion synthesis of SrZrO{sub 3} perovskite at relatively low temperature. • EPR evidence for ferromagnetic resonance. • Positive sign of the Curie–Weiss temperature ~8.7 K. • Defect induced magnetism- Zirconium vacancy induces maximum magnetic moment.

  8. EPR study of Cu(2+) ion doped orotato(nicotinamid)cobalt(II) single crystal.

    Science.gov (United States)

    Yıldırım, I; Karabulut, B; Büyükgüngör, O

    2016-01-01

    We have studied the Cu(2+) ion doped orotato(nicotinamid)cobalt(II) complex by using EPR spectroscopy and X-ray diffraction. The single crystal is triclinic with the space group P1‾. The unit cell dimensions of the crystal are a=7.2785(4)Å, b=10.2349(5)Å, c=12.7372(6)Å, α=69.297(4)°, β=74.791(4)° and γ=76.995(4)°, with Z=2. We analyzed the EPR spectra of both single crystal and powder of the complex at room temperature. EPR analysis indicates the presence of only one Cu(2+) site. We obtained the spin Hamiltonian parameters from the single crystal data for the complex. The spin Hamiltonian parameters are gx=2.032, gy=2.116, gz=2.319, Ax=28G, Ay=66G, Az=126G. These data indicate that the symmetry of paramagnetic center is rhombic. We constructed the ground state wave function of the Cu(2+) ion. PMID:25704568

  9. EDF EPR project: operating principles validation and human factor engineering program

    International Nuclear Information System (INIS)

    This article describes the specificities of the operating principles chosen by EDF for the EPR project as a result of an extensive Human Factor Engineering program successfully implemented in an industrial project context. The design process and its achievements benefit of the EDF experience feedback not only in term of NPP operation - including the fully computerized control room of the N4-serie - but also in term of NPP designer. The elements exposed hereafter correspond to the basic design phase of EPR HMI which has been completed and successfully validated by the end of 2003. The article aims to remind the context of the project which basically consists in designing a modern and efficient HMI taking into account the operating needs while relying on proven and reliable technologies. The Human Factor Engineering program implemented merges these both aspects by : 1) being fully integrated within the project activities and scheduling; 2) efficiently taking into account the users needs as well as the feasibility constraints by relying on a multidisciplinary design team including HF specialists, I and C specialists, Process specialists and experienced operator representatives. The resulting design process makes a wide use of experience feedback and experienced operator knowledge to complete largely the existing standards for providing a fully useable and successful design method in an industrial context. The article underlines the design process highlights that largely contribute to the successful implementation of a Human Factor Engineering program for EPR. (authors)

  10. Entanglement conservation, ER=EPR, and a new classical area theorem for wormholes

    Science.gov (United States)

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

    2016-07-01

    We consider the question of entanglement conservation in the context of the ER=EPR correspondence equating quantum entanglement with wormholes. In quantum mechanics, the entanglement between a system and its complement is conserved under unitary operations that act independently on each; ER=EPR suggests that an analogous statement should hold for wormholes. We accordingly prove a new area theorem in general relativity: for a collection of dynamical wormholes and black holes in a spacetime satisfying the null curvature condition, the maximin area for a subset of the horizons (giving the largest area attained by the minimal cross section of the multi-wormhole throat separating the subset from its complement) is invariant under classical time evolution along the outermost apparent horizons. The evolution can be completely general, including horizon mergers and the addition of classical matter satisfying the null energy condition. This theorem is the gravitational dual of entanglement conservation and thus constitutes an explicit characterization of the ER=EPR duality in the classical limit.

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

    Science.gov (United States)

    Winter, Alette; Zabel, André; Strauch, Peter

    2012-01-01

    Ionic liquids (ILs) on the basis of metal containing anions and/or cations are of interest for a variety of technical applications e.g., synthesis of particles, magnetic or thermochromic materials. We present the synthesis and the results of electron paramagnetic resonance (EPR) spectroscopic analyses of a series of some new potential ionic liquids based on tetrachloridocuprates(II), [CuCl4]2−, with different sterically demanding cations: hexadecyltrimethylammonium 1, tetradecyltrimethylammonium 2, tetrabutylammonium 3 and benzyltriethylammonium 4. The cations in the new compounds were used to achieve a reasonable separation of the paramagnetic Cu(II) ions for EPR spectroscopy. The EPR hyperfine structure was not resolved. This is due to the exchange broadening, resulting from still incomplete separation of the paramagnetic Cu(II) centers. Nevertheless, the principal values of the electron Zeemann tensor (g║ and g┴) of the complexes could be determined. Even though the solid substances show slightly different colors, the UV/Vis spectra are nearly identical, indicating structural changes of the tetrachloridocuprate moieties between solid state and solution. The complexes have a promising potential e.g., as high temperature ionic liquids, as precursors for the formation of copper chloride particles or as catalytic paramagnetic ionic liquids. PMID:22408411

  12. Estimation of the absorbed dose in radiation-processed food. 4. EPR measurements on eggshell

    International Nuclear Information System (INIS)

    Fresh whole eggs were treated with ionizing radiation for Salmonellae control testing. The eggshell was then removed and examined by electron paramagnetic resonance (EPR) spectroscopy to determine if EPR could be used to (1) distinguish irradiated from unirradiated eggs and (2) assess the absorbed dose. No EPR signals were detected in unirradiated eggs, while strong signals were measurable for more than 200 days after irradiation. Although a number of OPR signals were measured,the most intense resonance (g = 2.0019) was used for dosimetry throughout the study. This signal was observed to increase linearly with dose (up to approximately 6 kGy), which decayed approximately 20 % within the first 5 days after irradiation and remained relatively constant thereafter. The standard added-dose method was used to assess, retrospectively, the dose to eggs processed at 0.2, 0.7, and 1.4 kGy. Relatively good results were obtained when measurement was made on the day the shell was reradiated; with this procedure estimates were better for shell processed at the lower doses

  13. EPR and optical absorption studies of VO2+ ions in alkaline earth aluminoborate glasses

    International Nuclear Information System (INIS)

    Electron paramagnetic resonance (EPR) and optical absorption studies have been carried out for VO2+ ions in calcium aluminoborate glasses. The EPR spectra of all the glass samples exhibit resonance signals, characteristic of VO2+ ions. The values of spin-Hamiltonian parameters indicate that the VO2+ ions in calcium aluminoborate glasses were present in octahedral co-ordination with a tetragonal compression and belong to C4v symmetry. The number of spins (N) participating in resonance was calculated as a function of concentration as well as temperature. It is observed that variation of N with temperature obeys the Boltzmann law. From the EPR data, the paramagnetic susceptibility (χ) is calculated at various temperatures and the Curie constant (C) was evaluated from the 1/χ-T graph. The Fermi contact interaction parameter (k), dipolar hyperfine coupling parameter (P) have been calculated and these values are found to be independent of V2O5 content and temperature. The optical absorption spectrum exhibits two bands corresponding to the d-d transition 2B2g → 2Eg and 2B2g → 2A1g in the order of increasing energy. The theoretical values of optical basicity (Λth) of the glasses have also been evaluated

  14. EPR investigation of gamma irradiated single crystal guaifenesin: A combined experimental and computational study

    Science.gov (United States)

    Tasdemir, Halil Ugur; Sayin, Ulku; Türkkan, Ercan; Ozmen, Ayhan

    2016-04-01

    Gamma irradiated single crystal of Guaifenesin (Glyceryl Guaiacolate), an important expectorant drug, were investigated with Electron Paramagnetic Resonance (EPR) spectroscopy between 123 and 333 K temperature at different orientations in the magnetic field. Considering the chemical structure and the experimental spectra of the gamma irradiated single crystal of guaifenesin sample, we assumed that alkoxy or alkyl-type paramagnetic species may be produced by irradiation. Depending on this assumption, eight possible alkoxy and alkyl-type radicals were modeled and EPR parameters of these modeled radicals were calculated using the B3LYP/6-311++G(d,p)-level of density functional theory (DFT). Theoretically calculated values of alkyl-type modeled radical(R3) are in good agreement with experimentally determined EPR parameters of single crystal. Furthermore, simulation spectra which are obtained by using the theoretical initial values are well matched with the experimental spectra. It was determined that a stable Cα •H2αCβHβCγH2γ (R3) alkyl radical was produced in the host crystal as a result of gamma irradiation.

  15. EPR and XPS measurements of polymeric catalysts doped with hereopolyacids in oxygen adsorption studies

    International Nuclear Information System (INIS)

    The goal of our studies was to determine the nature of interactions between catalytic active samples, such as polypyrrole (PPy) doped with: chloride anions, heteropolyacids such as H5PMo10V2O40, or H4SiW12O40, and oxygen particles. In order to reveal the mechanism of the linkage between the catalysts and oxygen we provided the electron paramagnetic resonance (EPR) measurements of synthesized samples in O2 and N2 flow. Moreover, the X-ray photoelectron spectroscopy (XPS) measurements were performed to show the properties of doped heteropolyacids and the state of nitrogen in polypyrrole matrix. The results of EPR studies of PPy(Cl), PPy(H4SiW12O40), PPy(H5PMo10V2O40) samples, show that the polypyrrole doped with chloride anions interacts much easier with oxygen than polypyrrole doped with heteropolyacids (in the above given order, of preference with the most active polypyrrole system first). It correlates with XPS results, which show that a molybdenium-vanadium anion is more reduced than a silicon-tungsten one. The redox reactions of heteropolyacids involve the oxidation-reduction of the conjugated polymer chain, leaving no or little place for interactions with oxygen. Polypyrrole doped with H4SiW12O40 shows some oxygen sensitivity as observed in the EPR studies, as opposed to polypyrrole doped with H5PMo10V2O40, which is in line with the XPS results

  16. Skeletal Muscle Oxygenation Measured by EPR Oximetry Using a Highly Sensitive Polymer-Encapsulated Paramagnetic Sensor.

    Science.gov (United States)

    Hou, H; Khan, N; Nagane, M; Gohain, S; Chen, E Y; Jarvis, L A; Schaner, P E; Williams, B B; Flood, A B; Swartz, H M; Kuppusamy, P

    2016-01-01

    We have incorporated LiNc-BuO, an oxygen-sensing paramagnetic material, in polydimethylsiloxane (PDMS), which is an oxygen-permeable, biocompatible, and stable polymer. We fabricated implantable and retrievable oxygen-sensing chips (40 % LiNc-BuO in PDMS) using a 20-G Teflon tubing to mold the chips into variable shapes and sizes for in vivo studies in rats. In vitro EPR measurements were used to test the chip's oxygen response. Oxygen induced linear and reproducible line broadening with increasing partial pressure (pO2). The oxygen response was similar to that of bare (unencapsulated) crystals and did not change significantly on sterilization by autoclaving. The chips were implanted in rat femoris muscle and EPR oximetry was performed repeatedly (weekly) for 12 weeks post-implantation. The measurements showed good reliability and reproducibility over the period of testing. These results demonstrated that the new formulation of OxyChip with 40 % LiNc-BuO will enable the applicability of EPR oximetry for long-term measurement of oxygen concentration in tissues and has the potential for clinical applications. PMID:27526163

  17. Cr3+-Doped Yb3Ga5O12 Nanophosphor: Synthesis, Optical, EPR, Studies

    Science.gov (United States)

    Singh, Vijay; Sivaramaiah, G.; Rao, J. L.; Singh, N.; Pathak, M. S.; Jirimali, H. D.; Singh, Pramod K.; Srivastava, Anoop K.; Dhoble, S. J.; Mohapatra, M.

    2016-08-01

    Gallium garnets of lanthanides are multifunctional materials especially known for their complicated structure and magnetic properties. In addition, with a suitable transition metal dopant ion, these matrices have been proved to be excellent materials for lasers. In particular, gallium garnet of ytterbium (Yb3Ga5O12) is known to possess excellent properties with regards to these applications. In this connection, Yb3Ga5O12 doped with Cr3+ nanophosphors were synthesized by a solution combustion route. The synthesized material was characterized by powder x-ray diffraction and scanning electron microscopy for phase purity and homogenous morphology. In order to ascertain the oxidation state of the doped ion, diffuse reflectance (DRF), photoluminescence (PL) and electron paramagnetic resonance (EPR) experiments were performed on the sample. The DRF and PL data suggested the stabilisation of the trivalent Cr ion in the matrix. The EPR spectra exhibited two resonance signals with effective g values at g ≈ 7.6 and 4. The EPR data corroborated the DRF and PL results, suggesting the stabilisation of Cr3+ in the matrix at octahedral-type geometries.

  18. Irradiated bivalve mollusks: Use of EPR spectroscopy for identification and dosimetry

    Science.gov (United States)

    Alberti, Angelo; Chiaravalle, Eugenio; Fuochi, Piergiorgio; Macciantelli, Dante; Mangiacotti, Michele; Marchesani, Giuliana; Plescia, Elena

    2011-12-01

    High energy radiation treatment of foodstuff for microbial control and shelf-life extension is being used in many countries. However, for consumer protection and information, the European Union has adopted the Directives 1999/2/EC and 1999/3/EC to harmonize the rules concerning the treatment and trade of irradiated foods in EU countries. Among the validated methods to detect irradiated foods the EU directives also include Electron Paramagnetic Resonance (EPR/ESR) spectroscopy.We describe herein the use of EPR for identification of four species of bivalve mollusks, i.e. brown Venus shells (Callista chione), clams (Tapes semidecussatus), mussels (Mytilus galloprovincialis) and oysters (Ostrea edulis) irradiated with 60Co γ-rays. EPR could definitely identify irradiated seashells due to the presence of long-lived free radicals, primarily CO2-, CO33-, SO2- and SO3- radical anions. The presence of other organic free radicals, believed to originate from conchiolin, a scleroprotein present in the shells, was also ascertained. The use of one of these radicals as a marker for irradiation of brown Venus shells and clams can be envisaged. We also propose a dosimetric protocol for the reconstruction of the administered dose in irradiated oysters.

  19. EPR observation of first point defects in cubic boron nitride crystalline powders

    Science.gov (United States)

    Nistor, S. V.; Stefan, M.; Schoemaker, D.; Dinca, G.

    2000-05-01

    An X-band electron paramagnetic resonance (EPR) study of nominally pure, diamond-like cubic boron nitride (c-BN) crystalline powders, has led to the first identification of a spectrum attributed to two related paramagnetic species. The composite EPR spectrum can be observed only in dark brown colored powders known to contain excess of boron. It consists of two superimposed lorentzian components, called D1 and D2, centered at g1=2.0063 and g2=2.0084, with peak-to-peak linewidths of 3.3 and 17.9 mT, respectively. The temperature dependence of the integrated intensities, their linewidths and intensity ratio D2/D1 allows one to conclude that the narrow line D1 originates from EPR transitions inside a S=1/2 ground doublet and the broad line D2 from transitions inside the excited levels of another center. Evidence suggests that both centers are boron related paramagnetic species.

  20. Study of the stability of EPR signals after irradiation of fingernail samples.

    Science.gov (United States)

    Reyes, Ricardo A; Trompier, François; Romanyukha, Alexander

    2012-08-01

    Previous studies have suggested that the electron paramagnetic resonance in fingernails can be used for radiation dosimetry purposes. Use of fingernails as an emergency dosimeter has benefits of easy, noninvasive sampling and fast dose measurements (∼10 min) potentially in field conditions and almost immediately after an exposure event. This study represents the next step in the development of EPR fingernail dosimetry; e.g., evaluation of the stability of the radiation-induced signal (RIS) at different storage and irradiation conditions. RIS fading during storage in both stressed (untreated) and unstressed (soaked in water) samples (n = 20) was studied at two temperature conditions: freezing (temp ≈ -20°C) and room temperature (20-24°C). Fingernail samples with the same clipping size and number and irradiated to 15 and 20 Gy were measured for over 200 d. Those irradiated to 100 and 200 Gy were measured for 114 d. The other group of samples irradiated to 1, 3, 8, and 20 Gy was followed for 25 mo of storage time. This study demonstrated that all samples that were kept at low freezing temperatures showed a stable RIS with no significant fading. All samples that were kept at room temperatures showed an initial fading of the signal with a slow rise of the EPR signal after irradiation with time to a saturation level. Obtained results allow making recommendations on the appropriate storage conditions of fingernails for EPR dosimetry use. PMID:22951476

  1. A 5 tesla superconducting magnet and cryostats for an EPR/EMR spectrometer

    International Nuclear Information System (INIS)

    An Electron Paramagnetic Resonance Ferromagnetic Resonance (EPR/FMR) spectrometer, using Ka-band (26.5-40 GHz) and U-band (40-60 GHz), is built for resonance measurements on among others large magnetic thin films. It has the following features: A superconducting magnet with a homogeneous magnetic field up to 5 tesla. A free rotation of magnet field around the sample. A broad temperature range of the EPR/FMR sample (4 to 300 K). This paper concerns the cryogenic part of the spectrometer, consisting of two cryostats. Firstly, there is a cryostat having a room temperature vertical inlet tube, that gives access to the centre of the magnet. This cryostat can be rotated around the central axis of the inlet tube and enables rotation of the magnetic field around a fixed sample, placed in the center of the magnet. To reduce liquid helium evaporation special care is taken in the construction of the cryostat, by applying helium gas heat exchangers for instance. This cryostat contains a superconducting Helmoholz-like coil. Secondly there is a flow cryostat placed freely in the inlet tube of the first cryostat. This cryostat is used to cool the EPR/FMR sample. Special attention is paid to the construction of both cryostats, as well as to the design-calculations and construction of the superconducting magnet coil. The calculations are compared with experimental data

  2. EPR study of the reactions of tumour and normal tissues under ionizing radiation

    International Nuclear Information System (INIS)

    Data on the EPR spectrum characteristics of irradiated tissues of tumour-free animals and animals with tumour are presented. Mice of the Csub(3)Hsub(A) line were used in the experiments. Hepatoma was subcutaneously transplanted with the suspension of tumour tissue reduced to fragments. Animals were killed in 6-8 days after transplantation and in the case of tumour-free animals liver was immediately isolated while in the case of animals with tumour isolated were liver and tumour. Tissues cut with scissors were frozen in liquid nitrogen. Tissue samples were exposed to 60Co at 1 Mrad dose and -196 deg C. On the base of the data it has been concluded: firstly, there are differences between the EPR spectra of normal and tumour tissue samples irradiated at -196 deg C. Asymmetryc signal with Δ H=Ge and g=2.0005 (''tumour signal'') is typical only for the EPR spectra of tumour and liver tissues of the animal with tumour. Thus, in the -author's opinion, irradiation use turns out to be useful for detecting the difference between the normal and tumour tissues. Secondly, ''tumour signal'' intensity changes after ionol incorporation into animal organism, used as a modificator of tissue sensitivity to the irradiation effect

  3. On the zigzagging causility model of EPR correlations and on the interpretation of quantum mechanics

    Science.gov (United States)

    de Beauregard, O. Costa

    1988-09-01

    Being formalized inside the S-matrix scheme, the zigzagging causility model of EPR correlations has full Lorentz and CPT invariance. EPR correlations, proper or reversed, and Wheeler's smoky dragon metaphor are respectively pictured in spacetime or in the momentum-energy space, as V-shaped, A-shaped, or C-shaped ABC zigzags, with a summation at B over virtual states |B> = *. The formal parrallelism breaks down at the level of interpretation because (A|C) = ||2. CPT invariance implies the Fock and Watanabe principle that, in quantum mechanics, retarded (advanced) waves are used for prediction (retrodiction), an expression of which is = = , with |Φ> denoting a preparation, |Ψ> a measurement, and U the evolution operator. The transformation |Ψ> = |UΦ> or |Φ> = |U-1Ψ> exchanges the “preparation representation” and the “measurement representation” of a system and is ancillary in the formalization of the quantum chance game by the “wavelike algebra” of conditional amplitude. In 1935 EPR overlooked that a conditional amplitude = Σ between the two distant measurements is at stake, and that only measurements actually performed do make sense. The reversibility = * implies that causality is CPT-invariant, or arrowless, at the microlevel. Arrowed causality is a macroscopic emergence, corollary to wave retardation and probability increase. Factlike irreversibility states repression, not suppression, of “blind statistical retrodiction”—that is, of “final cause.”

  4. X-ray absorption spectroscopy and EPR studies of oriented spinach thylakoid preparations

    Energy Technology Data Exchange (ETDEWEB)

    Andrews, J.C. [Univ. of California, Berkeley, CA (United States). Dept. of Chemistry]|[Lawrence Berkeley Lab., CA (United States). Structural Biology Div.

    1995-08-01

    In this study, oriented Photosystem II (PS II) particles from spinach chloroplasts are studied with electron paramagnetic resonance (EPR) and x-ray absorption spectroscopy (XAS) to determine more details of the structure of the oxygen evolving complex (OEC). The nature of halide binding to Mn is also studied with Cl K-edge and Mn EXAFS (extended x-ray absorption fine structure) of Mn-Cl model compounds, and with Mn EXAFS of oriented PS II in which Br has replaced Cl. Attention is focused on the following: photosynthesis and the oxygen evolving complex; determination of mosaic spread in oriented photosystem II particles from signal II EPR measurement; oriented EXAFS--studies of PS II in the S{sub 2} state; structural changes in PS II as a result of treatment with ammonia: EPR and XAS studies; studies of halide binding to Mn: Cl K-edge and Mn EXAFS of Mn-Cl model compounds and Mn EXAFS of oriented Br-treated photosystem II.

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

    Directory of Open Access Journals (Sweden)

    Udo Kielmann

    2014-02-01

    Full Text Available Polymer-clay nanocomposites (PCNCs containing either a rubber or an acrylate polymer were prepared by drying or co-precipitating polymer latex and nanolayered clay (synthetic and natural suspensions. The interface between the polymer and the clay nanoparticles was studied by electron paramagnetic resonance (EPR techniques by selectively addressing spin probes either to the surfactant layer (labeled stearic acid or the clay surface (labeled catamine. Continuous-wave (CW EPR studies of the surfactant dynamics allow to define a transition temperature T* which was tentatively assigned to the order-disorder transition of the surfactant layer. CW EPR studies of PCNC showed that completely exfoliated nanoparticles coexist with agglomerates. HYSCORE spectroscopy in PCNCs showed couplings within the probe −assigned with DFT computations− and couplings with nuclei of the environment, 1H and 23Na for the surfactant layer probe, and 29Si, 7Li, 19F and 23Na for the clay surface probe. Analysis of these couplings indicates that the integrity of the surfactant layer is conserved and that there are sizeable ionic regions containing sodium ions directly beyond the surfactant layer. Simulations of the very weak couplings demonstrated that the HYSCORE spectra are sensitive to the composition of the clay and whether or not clay platelets stack.

  6. EPR Distance Measurements in Native Proteins with Genetically Encoded Spin Labels.

    Science.gov (United States)

    Schmidt, Moritz J; Fedoseev, Artem; Bücker, Dennis; Borbas, Julia; Peter, Christine; Drescher, Malte; Summerer, Daniel

    2015-12-18

    The genetic encoding of nitroxide amino acids in combination with electron paramagnetic resonance (EPR) distance measurements enables precise structural studies of native proteins, i.e. without the need for mutations to create unique reactive sites for chemical labeling and thus with minimal structural perturbation. We here report on in vitro DEER measurements in native E. coli thioredoxin (TRX) that establish the nitroxide amino acid SLK-1 as a spectroscopic probe that reports distances and conformational flexibilities in the enzyme with nonmutated catalytic centers that are not accessible by the use of the traditional methanethiosulfonate spin label (MTSSL). We generated a rotamer library for SLK-1 that in combination with molecular dynamics (MD) simulation enables predictions of distance distributions between two SLK-1 labels incorporated into a target protein. Toward a routine use of SLK-1 for EPR distance measurements in proteins and the advancement of the approach to intracellular environments, we study the stability of SLK-1 in E. coli cultures and lysates and establish guidelines for protein expression and purification that offer maximal nitroxide stability. These advancements and insights provide new perspectives for facile structural studies of native, endogenous proteins by EPR distance measurements.

  7. The role of EPR spectroscopy in studies of the oxidative status of biological systems and the antioxidative properties of various compounds - REVIEW

    OpenAIRE

    IVAN SPASOJEVIĆ; MILOŠ MOJOVIĆ; ALEKSANDAR IGNJATOVIĆ; GORAN BAČIĆ

    2011-01-01

    In this era of intense study of free radicals and antioxidants, electron paramagnetic resonance (EPR) is arguably the best-suited technique for such research, particularly when considering biochemical and biological systems. No attempt was made to cover all the topics of EPR application but instead attention was restricted to two areas that are both novel and received less attention in previous reviews. In the first section, the application of EPR in assessing the oxidative status of various ...

  8. Características de los usuarios del Centro de Recursos para el Aprendizaje y la Investigación de la Universidad de Cienfuegos

    Directory of Open Access Journals (Sweden)

    Aylén Pérez Borges

    2015-02-01

    Full Text Available Objetivo: Caracterizar a los usuarios del Centro de Recursos para el Aprendizaje y la Investigación (CRAI de la Universidad de Cienfuegos “Carlos Rafael Rodríguez”. Método: Se realizó un análisis bibliográfico de los términos relacionados con el estudio, un análisis de la metodología AMIGA, así como de las estadísticas que brinda el sistema automatizado de préstamos de esta biblioteca universitaria sobre los usuarios que más visitan el centro. Resultados: Se identificaron diversos grupos de usuarios a nivel de estudiantes, profesores, facultades, centros universitarios municipales, y centros de estudios; a la vez que dos grupos centrales: usuarios reales y potenciales. Conclusiones: Se conocieron algunas de las características de los usuarios del CRAI, partiendo de los grupos identificados por el centro, teniendo en cuenta aspectos como sus niveles educacionales e intereses. Se considera que un estudio más detallado puede quedar abierto para cumplimentar este objetivo a un nivel mayormente exhaustivo.

  9. Determinación del tamaño racional del bloque para la estimación de los recursos minerales en el yacimiento “Mariel”

    Directory of Open Access Journals (Sweden)

    Orestes Gómez-González

    2011-12-01

    Full Text Available La calidad de la estimación de recursos minerales es uno de los temas más importantes en la industria geológica-minera actual. El desarrollo de los sistemas automatizados en este campo ha permitido un incremento en la calidad de las estimaciones en diferentes tipos de yacimientos, pero aún existen elementos de carácter subjetivo que influyen directamente en la precisión y exactitud de los cálculos, uno de ellos es el tamaño del bloque de estimación. Para la selección de éste se han utilizado fundamentalmente criterios de carácter económico y minero. En este trabajo se demuestra la influencia del tamaño del bloque de estimación en la precisión y exactitud de los recursos estimados, utilizando procedimientos conjuntos de estimación y simulación geoestadística. El procedimiento se aplica en el yacimiento Mariel de materia prima para cemento y la metodología propuesta puede ser aplicable a otros casos de estudio.

  10. EPR Studies of DOPA–Melanin Complexes with Netilmicin and Cu(II) at Temperatures in the Range of 105–300 K

    OpenAIRE

    Zdybel, Magdalena; Pilawa, Barbara; Buszman, Ewa; Wrześniok, Dorota; Krzyminiewski, Ryszard; Kruczyński, Zdzisław

    2012-01-01

    The application of electron paramagnetic resonance (EPR) spectroscopy in pharmacy of melanin complexes with netilmicin and Cu(II) was presented. The continuous microwave saturation of EPR spectra of DOPA–melanin and the complexes was performed. EPR spectra were measured on an X-band (9.3 GHz) spectrometer at temperatures in the range of 105–300 K. Paramagnetic copper ions decrease the intensity of the EPR lines of melanin’s free radicals. It was found that fast spin–lattice relaxation charact...

  11. SU-C-BRD-05: Non-Invasive in Vivo Biodosimetry in Radiotherapy Patients Using Electron Paramagnetic Resonance (EPR) Spectroscopy

    International Nuclear Information System (INIS)

    Purpose: Medical intervention following a major, unplanned radiation event can elevate the human whole body exposure LD50 from 3 to 7 Gy. On a large scale, intervention cannot be achieved effectively without accurate and efficient triage. Current methods of retrospective biodosimetry are restricted in capability and applicability; published human data is limited. We aim to further develop, validate, and optimize an automated field-deployable in vivo electron paramagnetic resonance (EPR) instrument that can fill this need. Methods: Ionizing radiation creates highly-stable, carbonate-based free radicals within tooth enamel. Using a process similar to nuclear magnetic resonance, EPR directly measures the presence of radiation-induced free radicals. We performed baseline EPR measurements on one of the upper central incisors of total body irradiation (TBI) and head and neck (H&N) radiotherapy patients before their first treatment. Additional measurements were performed between subsequent fractions to examine the EPR response with increasing radiation dose. Independent dosimetry measurements were performed with optically-stimulated luminescent dosimeters (OSLDs) and diodes to more accurately establish the relationship between EPR signal and delivered radiation dose. Results: 36 EPR measurements were performed over the course of four months on two TBI and four H & N radiotherapy patients. We observe a linear increase in EPR signal with increasing dose across the entirety of the tested range. A linear least squares-weighted fit of delivered dose versus measured signal amplitude yields an adjusted R-square of 0.966. The standard error of inverse prediction (SEIP) is 1.77 Gy. For doses up to 7 Gy, the range most relevant to triage, we calculate an SEIP of 1.29 Gy. Conclusion: EPR spectroscopy provides a promising method of retrospective, non-invasive, in vivo biodosimetry. Our preliminary data show an excellent correlation between predicted signal amplitude and delivered

  12. SU-C-BRD-05: Non-Invasive in Vivo Biodosimetry in Radiotherapy Patients Using Electron Paramagnetic Resonance (EPR) Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Bahar, N; Roberts, K; Stabile, F; Mongillo, N; Decker, RD; Wilson, LD; Husain, Z; Contessa, J; Carlson, DJ [Yale University School of Medicine, New Haven, Connecticut (United States); Williams, BB; Flood, AB; Swartz, HM [Geisel Medical School at Dartmouth University, Hanover, New Hampshire (United States)

    2015-06-15

    Purpose: Medical intervention following a major, unplanned radiation event can elevate the human whole body exposure LD50 from 3 to 7 Gy. On a large scale, intervention cannot be achieved effectively without accurate and efficient triage. Current methods of retrospective biodosimetry are restricted in capability and applicability; published human data is limited. We aim to further develop, validate, and optimize an automated field-deployable in vivo electron paramagnetic resonance (EPR) instrument that can fill this need. Methods: Ionizing radiation creates highly-stable, carbonate-based free radicals within tooth enamel. Using a process similar to nuclear magnetic resonance, EPR directly measures the presence of radiation-induced free radicals. We performed baseline EPR measurements on one of the upper central incisors of total body irradiation (TBI) and head and neck (H&N) radiotherapy patients before their first treatment. Additional measurements were performed between subsequent fractions to examine the EPR response with increasing radiation dose. Independent dosimetry measurements were performed with optically-stimulated luminescent dosimeters (OSLDs) and diodes to more accurately establish the relationship between EPR signal and delivered radiation dose. Results: 36 EPR measurements were performed over the course of four months on two TBI and four H & N radiotherapy patients. We observe a linear increase in EPR signal with increasing dose across the entirety of the tested range. A linear least squares-weighted fit of delivered dose versus measured signal amplitude yields an adjusted R-square of 0.966. The standard error of inverse prediction (SEIP) is 1.77 Gy. For doses up to 7 Gy, the range most relevant to triage, we calculate an SEIP of 1.29 Gy. Conclusion: EPR spectroscopy provides a promising method of retrospective, non-invasive, in vivo biodosimetry. Our preliminary data show an excellent correlation between predicted signal amplitude and delivered

  13. SPIDYAN, a MATLAB library for simulating pulse EPR experiments with arbitrary waveform excitation

    Science.gov (United States)

    Pribitzer, Stephan; Doll, Andrin; Jeschke, Gunnar

    2016-02-01

    Frequency-swept chirp pulses, created with arbitrary waveform generators (AWGs), can achieve inversion over a range of several hundreds of MHz. Such passage pulses provide defined flip angles and increase sensitivity. The fact that spectra are not excited at once, but single transitions are passed one after another, can cause new effects in established pulse EPR sequences. We developed a MATLAB library for simulation of pulse EPR, which is especially suited for modeling spin dynamics in ultra-wideband (UWB) EPR experiments, but can also be used for other experiments and NMR. At present the command line controlled SPin DYnamics ANalysis (SPIDYAN) package supports one-spin and two-spin systems with arbitrary spin quantum numbers. By providing the program with appropriate spin operators and Hamiltonian matrices any spin system is accessible, with limits set only by available memory and computation time. Any pulse sequence using rectangular and linearly or variable-rate frequency-swept chirp pulses, including phase cycling can be quickly created. To keep track of spin evolution the user can choose from a vast variety of detection operators, including transition selective operators. If relaxation effects can be neglected, the program solves the Liouville-von Neumann equation and propagates spin density matrices. In the other cases SPIDYAN uses the quantum mechanical master equation and Liouvillians for propagation. In order to consider the resonator response function, which on the scale of UWB excitation limits bandwidth, the program includes a simple RLC circuit model. Another subroutine can compute waveforms that, for a given resonator, maintain a constant critical adiabaticity factor over the excitation band. Computational efficiency is enhanced by precomputing propagator lookup tables for the whole set of AWG output levels. The features of the software library are discussed and demonstrated with spin-echo and population transfer simulations.

  14. Effect of microwave power on EPR spectra of thermally sterilized eucerinum anhydricum

    Directory of Open Access Journals (Sweden)

    Ramos Paweł

    2015-07-01

    Full Text Available Free radicals formed during thermal sterilization of eucerinum anhydricum – the pharmaceutical base were examined by an X-band (9.3 GHz spectrometer. Eucerinum anhydricum was sterilized at different physical conditions according to the Polish Pharmacopeia norms. The samples were heated at temperatures: 160°C (120 min, 170°C (60 min, and 180°C (30 min. The aim of this study is to compare free radical concentration and effect of microwave power on EPR spectra of eucerinum anhydricum base thermally sterilized at different temperatures and periods of time. The effect of time storage on the free radicals in the heated samples was tested. Free radical concentrations in the sample stored 15 min strongly decreased with the increasing of sterilization temperature, probably as the result of recombination. Storage caused strong decrease of free radical concentrations in the samples, probably as the result of interactions with oxygen. It was observed to be independent of sterilization conditions from 2 days of storage and longer. Because of the lowest free radical concentration, for eucerinum anhydricum thermal sterilization at 180°C for 30 min is recommended. The sterilized samples should be stored at inert atmosphere without oxygen molecules. Fast spin-lattice relaxation processes existed in sterilized eucerinum anhydricum. The character of changes of amplitudes and linewidths of EPR lines with increasing of microwave power was the same for different storage times. The parameters of thermal sterilization and storage time influenced free radical concentration in eucerinum anhydricum, but magnetic spin-lattice interactions were unchanged. The usefulness of EPR spectroscopy in optimization of thermal sterilization process of eucerinum anhydricum was confirmed.

  15. Synthesis, characterization, photoluminescence and EPR investigations of Mn doped MgAl2O4 phosphors

    International Nuclear Information System (INIS)

    MgAl2O4:Mn phosphors have been prepared at 500 deg. C by combustion route. Powder X-ray diffraction (XRD) indicated the presence of mono-MgAl2O4 phase. Scanning electron microscopy showed that the powder particle crystallites are mostly angular. Fourier transform infrared spectroscopy confirmed the presence of AlO6 group which makes up the MgAl2O4 spinel. Photoluminescence studies showed green/red emission indicating that two independent luminescence channels in this phosphor. The green emission at 518 nm is due to 4 T 1→6 A 1 transition of Mn2+ ions. The emission at 650 nm is due to the charge-transfer deexcitation associated with the Mn ion. EPR spectrum exhibits allowed and forbidden hyperfine structure at g=2.003. The g∼2.00 is due to Mn2+ ion in an environment close to tetrahedral symmetry. It is observed that N and χ increase with decrease of temperature obeying the Boltzmann law. The variation of zero-field splitting parameter (D) with temperature is evaluated and discussed. - Graphical abstract: MgAl2O4:Mn phosphors have been prepared at 500 deg. C by combustion route and are well characterized by PXRD, SEM and FTIR. Photoluminescence studies showed green/red emission indicating two independent luminescence channels in this phosphor. EPR spectrum exhibits allowed and forbidden hyperfine structure at g=2.003. From EPR spectra the spin-Hamiltonian parameters have been evaluated and discussed

  16. NANOSCOPIC MOLECULAR CLUSTER V15: HIGH-FIELD EPR AND MAGNETIZATION AT ULTRA-LOW TEMPERATURES

    Directory of Open Access Journals (Sweden)

    Boris Tsukerblat

    2007-06-01

    Full Text Available n this paper we give a short overview of our efforts in the understanding of the magnetic properties of the fascinating nanoscopic cluster K6[VIV15As6O42(H2O]·8H2O (hereafter V15 exhibiting layers of magnetization. We analyze EPR and adiabatic magnetization of the V15 cluster with a triangular VIV3 array causing spin frustration. A model for V15 includes isotropic and antisymmetric (AS exchange interactions in the general form compatible with the trigonal symmetry. Orientation of the AS vector (but not only its absolute value is shown to play an important physical role in spin-frustrated systems. We were able to reach perfect fit to the experimental data on the stepwise dependence of magnetization vs. field at ultra-low temperatures. Furthermore, it was possible for the first time to estimate precisely two components of the AS vector coupling constant, namely, in-plane component and the perpendicular part. We show that only intramultiplet transitions in EPR are allowed when the vector of AS exchange is normal to the plane of vanadium triangle, meanwhile the in-plane part of AS exchange gives rise to a series of weak intermultiplet transitions. Experimental data on high-frequency EPR of V15 at low temperatures are discussed. The spin-vibronic effects in trimeric spin frustrated clusters are also studied and an important role of the interplay between the AS exchange and Jahn-Teller interaction is revealed. The results clarify the concept of spin-frustration in view of its magnetic and spectroscopic manifestations in metal clusters.

  17. XRD and EPR structural investigation of some zinc borate glasses doped with iron ions

    Science.gov (United States)

    Stefan, Razvan; Pascuta, Petru; Popa, Adriana; Raita, Oana; Indrea, Emil; Culea, Eugen

    2012-02-01

    Glasses in the system xFe2O3·(100-x) [45ZnO·55B2O3] (0≤x≤10 mol%) have been prepared by melting at 1200 °C and rapidly cooling at room temperature. The obtained samples were submitted to an additional thermal treatment at 570 °C for 12 h in order to relax the glass structure as well as to improve the local order. The as cast and heat treated samples were investigated using X-ray diffraction (XRD) and electron paramagnetic resonance (EPR) measurements. The XRD patterns of all the studied samples show their vitreous nature. Structural modifications occurring in the heat treated samples compared to the untreated ones have been pointed out. EPR spectra of untreated and heat treated samples revealed resonance absorptions centered at g≈2.0, g≈4.3 and g≈6.4. The compositional variation of the line intensity and linewidth of the absorptions from g≈4.3 and g≈2.0 have been interpreted in terms of the variation in the concentration of the Fe3+ ions and the interaction between the iron ions. The EPR spectra of the untreated samples containing 5 mol% Fe2O3 have been studied at different temperatures (110-290 K). The line intensity of the resonance signals decreases with increase in temperature whereas the linewidth is found to be independent of temperature. It was also found that the temperature variation of reciprocal line intensity obeys the Boltzmann law.

  18. Application of Electron Paramagnetic Resonance (EPR Oximetry to Monitor Oxygen in Wounds in Diabetic Models.

    Directory of Open Access Journals (Sweden)

    Céline M Desmet

    Full Text Available A lack of oxygen is classically described as a major cause of impaired wound healing in diabetic patients. Even if the role of oxygen in the wound healing process is well recognized, measurement of oxygen levels in a wound remains challenging. The purpose of the present study was to assess the value of electron paramagnetic resonance (EPR oximetry to monitor pO2 in wounds during the healing process in diabetic mouse models. Kinetics of wound closure were carried out in streptozotocin (STZ-treated and db/db mice. The pO2 was followed repeatedly during the healing process by 1 GHz EPR spectroscopy with lithium phthalocyanine (LiPc crystals used as oxygen sensor in two different wound models: a full-thickness excisional skin wound and a pedicled skin flap. Wound closure kinetics were dramatically slower in 12-week-old db/db compared to control (db/+ mice, whereas kinetics were not statistically different in STZ-treated compared to control mice. At the center of excisional wounds, measurements were highly influenced by atmospheric oxygen early in the healing process. In pedicled flaps, hypoxia was observed early after wounding. While reoxygenation occurred over time in db/+ mice, hypoxia was prolonged in the diabetic db/db model. This observation was consistent with impaired healing and microangiopathies observed using intravital microscopy. In conclusion, EPR oximetry using LiPc crystals as the oxygen sensor is an appropriate technique to follow wound oxygenation in acute and chronic wounds, in normal and diabetic animals. Nevertheless, the technique is limited for measurements in pedicled skin flaps and cannot be applied to excisional wounds in which diffusion of atmospheric oxygen significantly affects the measurements.

  19. SPIDYAN, a MATLAB library for simulating pulse EPR experiments with arbitrary waveform excitation.

    Science.gov (United States)

    Pribitzer, Stephan; Doll, Andrin; Jeschke, Gunnar

    2016-02-01

    Frequency-swept chirp pulses, created with arbitrary waveform generators (AWGs), can achieve inversion over a range of several hundreds of MHz. Such passage pulses provide defined flip angles and increase sensitivity. The fact that spectra are not excited at once, but single transitions are passed one after another, can cause new effects in established pulse EPR sequences. We developed a MATLAB library for simulation of pulse EPR, which is especially suited for modeling spin dynamics in ultra-wideband (UWB) EPR experiments, but can also be used for other experiments and NMR. At present the command line controlled SPin DYnamics ANalysis (SPIDYAN) package supports one-spin and two-spin systems with arbitrary spin quantum numbers. By providing the program with appropriate spin operators and Hamiltonian matrices any spin system is accessible, with limits set only by available memory and computation time. Any pulse sequence using rectangular and linearly or variable-rate frequency-swept chirp pulses, including phase cycling can be quickly created. To keep track of spin evolution the user can choose from a vast variety of detection operators, including transition selective operators. If relaxation effects can be neglected, the program solves the Liouville-von Neumann equation and propagates spin density matrices. In the other cases SPIDYAN uses the quantum mechanical master equation and Liouvillians for propagation. In order to consider the resonator response function, which on the scale of UWB excitation limits bandwidth, the program includes a simple RLC circuit model. Another subroutine can compute waveforms that, for a given resonator, maintain a constant critical adiabaticity factor over the excitation band. Computational efficiency is enhanced by precomputing propagator lookup tables for the whole set of AWG output levels. The features of the software library are discussed and demonstrated with spin-echo and population transfer simulations.

  20. SPIDYAN, a MATLAB library for simulating pulse EPR experiments with arbitrary waveform excitation.

    Science.gov (United States)

    Pribitzer, Stephan; Doll, Andrin; Jeschke, Gunnar

    2016-02-01

    Frequency-swept chirp pulses, created with arbitrary waveform generators (AWGs), can achieve inversion over a range of several hundreds of MHz. Such passage pulses provide defined flip angles and increase sensitivity. The fact that spectra are not excited at once, but single transitions are passed one after another, can cause new effects in established pulse EPR sequences. We developed a MATLAB library for simulation of pulse EPR, which is especially suited for modeling spin dynamics in ultra-wideband (UWB) EPR experiments, but can also be used for other experiments and NMR. At present the command line controlled SPin DYnamics ANalysis (SPIDYAN) package supports one-spin and two-spin systems with arbitrary spin quantum numbers. By providing the program with appropriate spin operators and Hamiltonian matrices any spin system is accessible, with limits set only by available memory and computation time. Any pulse sequence using rectangular and linearly or variable-rate frequency-swept chirp pulses, including phase cycling can be quickly created. To keep track of spin evolution the user can choose from a vast variety of detection operators, including transition selective operators. If relaxation effects can be neglected, the program solves the Liouville-von Neumann equation and propagates spin density matrices. In the other cases SPIDYAN uses the quantum mechanical master equation and Liouvillians for propagation. In order to consider the resonator response function, which on the scale of UWB excitation limits bandwidth, the program includes a simple RLC circuit model. Another subroutine can compute waveforms that, for a given resonator, maintain a constant critical adiabaticity factor over the excitation band. Computational efficiency is enhanced by precomputing propagator lookup tables for the whole set of AWG output levels. The features of the software library are discussed and demonstrated with spin-echo and population transfer simulations. PMID:26773526

  1. Water accessibility in a membrane-inserting peptide comparing Overhauser DNP and pulse EPR methods

    Science.gov (United States)

    Segawa, Takuya F.; Doppelbauer, Maximilian; Garbuio, Luca; Doll, Andrin; Polyhach, Yevhen O.; Jeschke, Gunnar

    2016-05-01

    Water accessibility is a key parameter for the understanding of the structure of biomolecules, especially membrane proteins. Several experimental techniques based on the combination of electron paramagnetic resonance (EPR) spectroscopy with site-directed spin labeling are currently available. Among those, we compare relaxation time measurements and electron spin echo envelope modulation (ESEEM) experiments using pulse EPR with Overhauser dynamic nuclear polarization (DNP) at X-band frequency and a magnetic field of 0.33 T. Overhauser DNP transfers the electron spin polarization to nuclear spins via cross-relaxation. The change in the intensity of the 1H NMR spectrum of H2O at a Larmor frequency of 14 MHz under a continuous-wave microwave irradiation of the nitroxide spin label contains information on the water accessibility of the labeled site. As a model system for a membrane protein, we use the hydrophobic α-helical peptide WALP23 in unilamellar liposomes of DOPC. Water accessibility measurements with all techniques are conducted for eight peptides with different spin label positions and low radical concentrations (10-20 μM). Consistently in all experiments, the water accessibility appears to be very low, even for labels positioned near the end of the helix. The best profile is obtained by Overhauser DNP, which is the only technique that succeeds in discriminating neighboring positions in WALP23. Since the concentration of the spin-labeled peptides varied, we normalized the DNP parameter ɛ, being the relative change of the NMR intensity, by the electron spin concentration, which was determined from a continuous-wave EPR spectrum.

  2. Cooper-pair splitter: towards an efficient source of spin-entangled EPR pairs

    Science.gov (United States)

    Schonenberger, Christian

    2011-03-01

    In quantum mechanics the properties of two and more particles can be entangled. In basic science pairs of entangled particles, so called Einstein-Podolsky-Rosen (EPR) pairs, play a special role as toy objects for fundamental studies. They provide such things as ``spooky interaction at distance,'' but they also enable secure encoding and teleportation and are thus important for applications in quantum information technology. Whereas EPR pairs of photons can be generated by parametric down conversion (PDC) in a crystal, a similar source for EPR pairs of electrons does not exists yet. In several theory papers, it has been suggested to use a superconductor for this purpose. The superconducting ground state is formed by a condensate of Cooper-pairs which are electron pairs in a spin-singlet state. Since there are many Cooper pairs in a metallic superconductor like Al, the main tasks are to extract Cooper pairs one by one and to split them into different arms. A controlled and efficient splitting is possible if one makes use of Coulomb interaction. This has recently be demonstrated by two groups [2-4] using hybrid quantum-dot devices with both superconducting and normal metal contacts. In the present talk, I will discuss the Cooper-pair splitter results from the Basel-Budapest-Copenhagen team and compare with the other experiments. As an outlook we discuss approaches that aim at entanglement detection. The Cooper pair splitter holds great promises because very large splitting efficiencies approaching 100% and large pair current rates appear feasible. This work has been done by L. Hofstetter, S. Csonka, A. Geresdi, M. Aagesen, J. Nygard and C. Schönenberger

  3. EPR study of N+-ion-induced free radical formation in antibiotic-producers

    International Nuclear Information System (INIS)

    Under the room temperature, electron paramagnetic resonance (EPR) spectrometer was used to study free radical formation in antibiotic-producers in order to investigate antibiotic-producer mutagenic breeding, which were induced by N+ ion implanting into antibiotic-producers (e.g., Streptomyces ribosidificus, Streptomyces kanamyceticus and the phage-resistant culture of Streptomyces kanamyceticus). The results show that a lot of free radicals can be induced by N+ ion implanting into antibiotic-producers, and the yields of the free radicals increase with implanting dose. The death rate of antibiotic-producers rises due to the increase of N+-ion-induced free radical yields. (author)

  4. A Multiparty Controlled Bidirectional Quantum Secure Direct Communication and Authentication Protocol Based on EPR Pairs

    Science.gov (United States)

    Chang, Yan; Zhang, Shi-Bin; Yan, Li-Li; Sheng, Zhi-Wei

    2013-06-01

    A multiparty controlled bidirectional quantum secure direct communication and authentication protocol is proposed based on EPR pair and entanglement swapping. The legitimate identities of communicating parties are encoded to Bell states which act as a detection sequence. Secret messages are transmitted by using the classical XOR operation, which serves as a one-time-pad. No photon with secret information transmits in the quantum channel. Compared with the protocols proposed by Wang et al. [Acta Phys. Sin. 56 (2007) 673; Opt. Commun. 266 (2006) 732], the protocol in this study implements bidirectional communication and authentication, which defends most attacks including the ‘man-in-the-middle’ attack efficiently.

  5. Analyzing three-player quantum games in an EPR type setup using geometric algebra

    CERN Document Server

    Chappell, James M; Abbott, Derek

    2010-01-01

    The framework for playing three-player quantum games in an Einstein-Podolsky-Rosen (EPR) type setting is investigated using the mathematical formalism of geometric algebra (GA). In this setting, the players' strategy sets remain identical to the ones in the mixed-strategy version of the classical game, which is obtained as a proper subset of the corresponding quantum game. Using GA and considering general symmetrical three-qubit pure states, we analyze the three-player quantum game of Prisoners' Dilemma.

  6. Bidirectional teleportation of a pure EPR state by using GHZ states

    Science.gov (United States)

    Hassanpour, Shima; Houshmand, Monireh

    2016-02-01

    In the present paper, a novel bidirectional quantum teleportation protocol is proposed. By using entanglement swapping technique, two GHZ states are shared as a quantum channel between Alice and Bob as legitimate users. In this scheme, based on controlled-not operation, single-qubit measurement, and appropriate unitary operations, two users can simultaneously transmit a pure EPR state to each other, While, in the previous protocols, the users can just teleport a single-qubit state to each other via more than four-qubit state. Therefore, the proposed scheme is economical compared with previous protocols.

  7. EPR-based approach for the localization of paramagnetic metal ions in biomolecules.

    Science.gov (United States)

    Abdullin, Dinar; Florin, Nicole; Hagelueken, Gregor; Schiemann, Olav

    2015-02-01

    Metal ions play an important role in the catalysis and folding of proteins and oligonucleotides. Their localization within the three-dimensional fold of such biomolecules is therefore an important goal in understanding structure-function relationships. A trilateration approach for the localization of metal ions by means of long-range distance measurements based on electron paramagnetic resonance (EPR) is introduced. The approach is tested on the Cu(2+) center of azurin, and factors affecting the precision of the method are discussed. PMID:25522037

  8. FTIR and EPR Studies of Nickel Substituted Nanostructured Mn Zn Ferrite

    OpenAIRE

    C. Venkataraju; Paulsingh, R.

    2014-01-01

    The spinel ferrite system Mn0.5-xNixZn0.5Fe2O4 is prepared by coprecipitation method. XRD analysis confirms the formation of ferrite phase in all the samples. The FTIR spectra of all the samples show two main absorption bands below 1000 cm−1. FTIR studies reveal cationic exchange between A site and B site. The magnetic moment calculated from EPR studies is lower when compared to the theoretical values. This confirms the existence of noncollinear magnetic structure arising due to spin canting ...

  9. Evaluation of a lithium formate EPR dosimetry system for dose measurements around Ir-192 brachytherapy sources

    OpenAIRE

    Antonovic, Laura; Gustafsson, Håkan; Alm Carlsson, Gudrun; Carlsson Tedgren, Åsa

    2009-01-01

    A dosimetry system using lithium formate monohydrate (HCO2Li center dot H2O) as detector material and electron paramagnetic resonance (EPR) spectroscopy for readout has been used to measure absorbed dose distributions around clinical Ir-192 sources. Cylindrical tablets with diameter of 4.5 mm, height of 4.8 mm, and density of 1.26 g/cm(3) were manufactured. Homogeneity test and calibration of the dosimeters were performed in a 6 MV photon beam. Ir-192 irradiations were performed in a PMMA pha...

  10. Identification of periplasmic nitrate reductase Mo(V) EPR signals in intact cells of Paracoccus denitrificans.

    Science.gov (United States)

    Sears, H J; Bennett, B; Spiro, S; Thomson, A J; Richardson, D J

    1995-08-15

    EPR spectroscopy has been successfully used to detect signals due to molybdenum (V) and ferric iron in intact cells of aerobically grown Paracoccus denitrificans. The signals are ascribed to the catalytic molybdenum centre and to the haem iron of the periplasmic nitrate reductase. These signals are absent from a mutant strain deficient in this enzyme. The Mo(V) signal is due to the High-g Split species which has been well characterized in the purified enzyme. This confirms that the High-g Split is the physiologically relevant signal of a number observed in the previous work on the purified enzyme. PMID:7646461

  11. Energy Dependence of EPR Signal in Synthetic and Biological Hydroxyapatite Irradiated with Photons

    International Nuclear Information System (INIS)

    Synthetic A-type carbonated apatite and enamel samples were irradiated using X rays and gamma rays of 137Cs and 60Co in the range of 47 keV to 1.25 MeV. The energy-dependent response of CO2- radicals induced by radiation in both systems is studied using electron paramagnetic resonance (EPR). No energy dependence was verified for synthetic apatites and enamel in the range of 58 to 1250 keV. The results are compared with the energy dependence of the same radicals induced in bones and enamel reported in the literature. (author)

  12. Efficient schemes of joint remote preparation with a passive receiver via EPR pairs

    Science.gov (United States)

    Ma, Song-Ya; Gao, Cong; Luo, Ming-Xing

    2015-11-01

    Novel schemes are put forward to execute the joint remote preparation of an arbitrary two-qubit state with a passive receiver via EPR pairs as the entangled channel. Compared with the previous protocols, the required multi-particle measurement is simplified and the classical communication cost is reduced. When the number of senders increases, the advantage is more evident. It means that the proposed schemes are more efficient in practice. Project supported by the National Natural Science Foundation of China (Grant Nos. 61201253, 61303039, 61572246, and 61502147) and the Fundamental Research Fund for the Central Universities of China (Grant No. 2682014CX095).

  13. Application of Electron Paramagnetic Resonance (EPR) Oximetry to Monitor Oxygen in Wounds in Diabetic Models

    OpenAIRE

    Desmet, Céline M.; Aurore Lafosse; Sophie Vériter; Paolo E. Porporato; Pierre Sonveaux; Denis Dufrane; Philippe Levêque; Bernard Gallez

    2015-01-01

    A lack of oxygen is classically described as a major cause of impaired wound healing in diabetic patients. Even if the role of oxygen in the wound healing process is well recognized, measurement of oxygen levels in a wound remains challenging. The purpose of the present study was to assess the value of electron paramagnetic resonance (EPR) oximetry to monitor pO2 in wounds during the healing process in diabetic mouse models. Kinetics of wound closure were carried out in streptozotocin (STZ)-t...

  14. Teleportation of n-Particle State via n Pairs of EPR Channels

    Institute of Scientific and Technical Information of China (English)

    CAO Min; ZHU Shi-Qun; FANG Jian-Xing

    2004-01-01

    The teleportation of an arbitrary n-particle state (n ≥ 1) is proposed if n pairs of identical EPR states are utilized as quantum channels. Independent Bell state measurements are performed for joint measurement. By using a special Latin square of order 2n(n ≥ 1), explicit expressions of outcomes after the Bell state measurements by Alice (sender) and the corresponding unitary transformations by Bob (receiver) can be derived. It is shown that the teleportation of n-particle state can be implemented by a series of single-qubit teleportation.

  15. Single ion anisotropy of Mn doped GaAs measured by EPR

    OpenAIRE

    Fedorych, O. M.; Hankiewicz, E. M.; Wilamowski, Z; J. Sadowski

    2001-01-01

    Electron paramagnetic resonance (EPR) study of MBE grown Mn doped GaAs is presented. The resolved fine structure allows us to evaluate the crystal field parameters of the spin Hamiltonian. The obtained cubic constant is a= -14.1 10^-4/cm. The axial field parameter, D, increases with Mn concentration, x, i.e., with the strain of (Ga,Mn)As layers. Extrapolation of D shows that the single ion anisotropy is the important contribution to the magnetic anisotropy which is observed in ferromagnetic l...

  16. EPR Oximetry for Investigation of Hyperbaric O2 Pre-treatment for Tumor Radiosensitization.

    Science.gov (United States)

    Williams, Benjamin B; Hou, Huagang; Coombs, Rachel; Swartz, Harold M

    2016-01-01

    A number of studies have reported benefits associated with the application of hyperbaric oxygen treatment (HBO) delivered immediately prior to radiation therapy. While these studies provide evidence that pre-treatment with HBO may be beneficial, no measurements of intratumoral pO2 were carried out and they do not directly link the apparent benefits to decreased hypoxic fractions at the time of radiation therapy. While there is empirical evidence and some theoretical basis for HBO to enhance radiation therapy, without direct and repeated measurements of its effects on pO2, it is unlikely that the use of HBO can be understood and optimized for clinical applications. In vivo EPR oximetry is a technique uniquely capable of providing repeated direct measurements of pO2 through a non-invasive procedure in both animal models and human patients. In order to evaluate the ability of pretreatment with HBO to elevate tumor pO2, a novel small animal hyperbaric chamber system was constructed that allows simultaneous in vivo EPR oximetry. This chamber can be placed within the EPR magnet and is equipped with a variety of ports for multiplace gas delivery, thermoregulation, delivery of anesthesia, physiologic monitoring, and EPR detection. Initial measurements were performed in a subcutaneous RIF-1 tumor model in C3H/HeJ mice. The mean baseline pO2 value was 6.0 ± 1.2 mmHg (N = 7) and responses to two atmospheres absolute pressure HBO varied considerably across subjects, within tumors, and over time. When an increase in pO2 was observed, the effect was transient in all but one case, with durations lasting from 5 min to over 20 min, and returned to baseline levels during HBO administration. These results indicate that without direct measurements of pO2 in the tissue of interest, it is likely to be difficult to know the effects of HBO on actual tissue pO2. PMID:27526165

  17. Splitting spacetime and cloning qubits: linking no-go theorems across the ER=EPR duality

    Energy Technology Data Exchange (ETDEWEB)

    Bao, Ning [Institute for Quantum Information and Matter, California Institute of Technology, Pasadena, CA 91125 (United States); Walter Burke Institute for Theoretical Physics, California Institute of Technology, Pasadena, CA 91125 (United States); Pollack, Jason; Remmen, Grant N. [Walter Burke Institute for Theoretical Physics, California Institute of Technology, Pasadena, CA 91125 (United States)

    2015-11-15

    We analyze the no-cloning theorem in quantum mechanics through the lens of the proposed ER=EPR (Einstein-Rosen = Einstein-Podolsky-Rosen) duality between entanglement and wormholes. In particular, we find that the no-cloning theorem is dual on the gravity side to the no-go theorem for topology change, violating the axioms of which allows for wormhole stabilization and causality violation. Such a duality between important no-go theorems elucidates the proposed connection between spacetime geometry and quantum entanglement. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  18. Teleportation of a two-atom entangled state using a single EPR pair in cavity QED

    Institute of Scientific and Technical Information of China (English)

    Ji Xin; Li Ke; Zhang Shou

    2006-01-01

    We propose a scheme for teleporting a two-atom entangled state in cavity quantum electrodynamics(QED).In the scheme,we choose a single Einstein-Podolsky-Rosen (EPR) pair as the quantum channel which is shared by the sender and the receiver.By using the atom-cavity-field interaction and introducing an additional atom,we can teleport the two-atom entangled state successfully with a probability of 1.0.Moreover,we show that the scheme is insensitive to cavity decay and thermal field.

  19. An in situ electrochemical cell for Q- and W-band EPR spectroscopy

    Science.gov (United States)

    Murray, Paul R.; Collison, David; Daff, Simon; Austin, Nicola; Edge, Ruth; Flynn, Brian W.; Jack, Lorna; Leroux, Fanny; McInnes, Eric J. L.; Murray, Alan F.; Sells, Daniel; Stevenson, Tom; Wolowska, Joanna; Yellowlees, Lesley J.

    2011-12-01

    A simple design for an in situ, three-electrode spectroelectrochemical cell is reported that can be used in commercial Q- and W-band (ca. 34 and 94 GHz, respectively) electron paramagnetic resonance (EPR) spectrometers, using standard sample tubing (1.0 and 0.5 mm inner diameter, respectively) and within variable temperature cryostat systems. The use of the cell is demonstrated by the in situ generation of organic free radicals (quinones and diimines) in fluid and frozen media, transition metal ion radical anions, and on the enzyme nitric oxide synthase reductase domain (NOSrd), in which a pair of flavin radicals are generated.

  20. Splitting Spacetime and Cloning Qubits: Linking No-Go Theorems across the ER=EPR Duality

    CERN Document Server

    Bao, Ning; Remmen, Grant N

    2015-01-01

    We analyze the no-cloning theorem in quantum mechanics through the lens of the proposed ER=EPR (Einstein-Rosen = Einstein-Podolsky-Rosen) duality between entanglement and wormholes. In particular, we find that the no-cloning theorem is dual on the gravity side to the no-go theorem for topology change, violating the axioms of which allows for wormhole stabilization and causality violation. Such a duality between important no-go theorems elucidates the proposed connection between spacetime geometry and quantum entanglement.

  1. Single crystal EPR study of VO(II)-doped cadmium potassium phosphate hexahydrate: A substitutional incorporation

    Indian Academy of Sciences (India)

    I Sougandi; T M Rajendiran; R Venkatesan; P Sambasiva Rao

    2002-10-01

    Single crystal EPR studies of VO(II)-doped cadmium potassium phosphate hexahydrate (CPPH) have been carried out at room temperature. The angular variation spectra in the three orthogonal planes indicate that the paramagnetic impurity has entered the lattice only substitutionally in place of Cd(II). Spin Hamiltonian parameters have been obtained from single crystal data. Powder spectra show a set of eight parallel and perpendicular features indicating the presence of only one site. The admixture coefficients have been calculated from the data, which agree well with the literature values.

  2. Minimization of actinide waste by multi-recycling of thoriated fuels in the EPR reactor

    OpenAIRE

    Nuttin A.; Siem S.; Ivanov E.; Méplan O.; David S; Guillemin P.; Wilson J.N.; Capellan N.; Rose S.J.

    2012-01-01

    The multi-recycling of innovative uranium/thorium oxide fuels for use in the European Pressurized water Reactor (EPR) has been investigated. If increasing quantities of 238U, the fertile isotope in standard UO2 fuel, are replaced by 232Th, then a greater yield of new fissile material (233U) is produced during the cycle than would otherwise be the case. This leads to economies of natural uranium of around 45% if the uranium in the spent fuel is multi-recycled. In addition we show that minor ac...

  3. Minimization of actinide waste by multirecycling of thoriated fuels in an EPR

    OpenAIRE

    2009-01-01

    This master’s thesis explores how to minimize the long-lived actinide waste that is produced in nuclear power plants by performing simulations of thoriated nuclear fuels in existing reactor designs. An European pressurized water reactor (EPR) assembly fueled with a mixture of thorium and highly enriched uranium (20% and 90% 235U) was simulated. The spent thoriated fuel is less active, and for a much shorter period of time, than uranium or uranium/plutonium fuels and less decay heat is gene...

  4. Nursing documentation with NANDA and NIC in a comprehensive HIS/EPR system.

    Science.gov (United States)

    Flø, Kåre

    2006-01-01

    DIPS nursing documentation system facilitates that nurses can write several types of notes into the EPR. Within these notes the nurses can register NANDA diagnoses and NIC interventions with nursing activities. To choose NANDA and NIC the nurse can use a search engine, or she can choose a relevant Care plan guideline and pick the suggested diagnoses and interventions from there. Diagnoses and interventions with nursing activities registered are presented in a Care plan. When a nurse writes a note for a patient she will always be presented the Care plan and she can easy evaluate and update the Care plan.

  5. Enactment of a decree for a EPR unit on the Flamanville site

    International Nuclear Information System (INIS)

    The decree allowing the construction of a EPR (European Pressurized Reactor) on the Flamanville site has been enacted through publishing in the official gazette on the 11. April 2007. This decree sets the technical specifications concerning: nuclear safety, radiation protection and environment protection that will have to be followed during the operating life of the reactor. This decree is the last step before construction works begin, this 1650 MWe reactor is expected to enter into service by 2012. The regional administrative jurisdiction has rejected 3 requests in annulment claimed by associations, upon the grounds that the 1986 law on the coastline development is not relevant in this case. (A.C.)

  6. Multifrequency cw-EPR and DFT Studies of an Apparent Compressed Octahedral Cu(II) Complex.

    Science.gov (United States)

    Hall, Nikita; Orio, Maylis; Gennari, Marcello; Wills, Christopher; Molton, Florian; Philouze, Christian; Jameson, Geoffrey B; Halcrow, Malcolm A; Blackman, Allan G; Duboc, Carole

    2016-02-15

    The syntheses and single-crystal X-ray structures of the mononuclear complexes [Cu(bmet)](ClO4)2·H2O, [Cu(bmet)]Br2·2MeCN, and [Zn(bmet)](ClO4)2·H2O (bmet = N,N'-bis(2,2'-bipyridin-6-ylmethyl)ethane-1,2-diamine) are described. All three complexes feature a central metal ion bound to all six N atoms of the bmet ligand, which displays a meridional-facial-facial-meridional (mffm) configuration. The three complexes show one N-M-N axis to be significantly shorter than the others in agreement with an apparent compressed octahedral geometry. The X-ray structures of a single crystal of [Cu(bmet)](ClO4)2·0.375H2O resolved from data recorded at different temperatures display no remarkable structural modifications. However, they all display both as a powder and, in solution, an axial g1 > g2 ≳ g3 > g(e) electron paramagnetic resonance (EPR) pattern at low temperature, which is indicative of tetragonally elongated octahedra, while at room temperature the Q-band EPR spectra display a more rhombic g1 ≳ g2 > g3 > g(e) pattern. The fully density functional theory optimized structure of the Cu(II) complexes displays significant structural modifications only along one N(imine)-M-N(amine) axis resulting in an elongated octahedral structure. Furthermore, the EPR parameters predicted from this structure are comparable to those determined experimentally from the axial EPR signal recorded at low temperature, consistent with the unpaired electron residing mainly in the {3d(x(2)-y(2))} orbital. The structural and electronic properties of [Cu(bmet)](2+) are different from those in other previously described dynamic Jahn-Teller systems. We propose that these data can be rationalized by a dynamic Jahn-Teller effect perturbed by the strain of the hexadentate bmet ligand.

  7. A Hash Based Remote User Authentication and Authenticated Key Agreement Scheme for the Integrated EPR Information System.

    Science.gov (United States)

    Li, Chun-Ta; Weng, Chi-Yao; Lee, Cheng-Chi; Wang, Chun-Cheng

    2015-11-01

    To protect patient privacy and ensure authorized access to remote medical services, many remote user authentication schemes for the integrated electronic patient record (EPR) information system have been proposed in the literature. In a recent paper, Das proposed a hash based remote user authentication scheme using passwords and smart cards for the integrated EPR information system, and claimed that the proposed scheme could resist various passive and active attacks. However, in this paper, we found that Das's authentication scheme is still vulnerable to modification and user duplication attacks. Thereafter we propose a secure and efficient authentication scheme for the integrated EPR information system based on lightweight hash function and bitwise exclusive-or (XOR) operations. The security proof and performance analysis show our new scheme is well-suited to adoption in remote medical healthcare services.

  8. High-pressure low-temperature locknut cell for both EPR and NMR studies to 10 kilobars and 77 K

    Science.gov (United States)

    Sinha, Shantanu; Srinivasan, R.

    1983-11-01

    A locked high-pressure cell with working pressure range up to 10 kbars suitable for low-temperature studies to 77 K has been described. It can be used for both EPR and NMR studies of single crystals (and other solid samples). The high-pressure seal and all other aspects of the cell remain the same for either application. Only a change of the bottom plug is required for a switch from a nuclear-magnetic-resonance (NMR) to an electron-paramagnetic-resonance (EPR) experiment. Details of the procedure for the calibration of pressure inside the cell at various temperatures are discussed. The performance of the cell in EPR (Cr3+ion) and NMR (27Al nucleus) studies is reported.

  9. Theoretical investigations of the optical and EPR spectra for trivalent cerium and ytterbium ions in orthorhombic YF3 crystal

    Science.gov (United States)

    Liu, Hong-Gang; Zheng, Wen-Chen

    2016-09-01

    The optical spectra and electron paramagnetic resonance (EPR) parameters (g factors and hyperfine structure constants A) for trivalent cerium and ytterbium ions in YF3 crystal with orthorhombic structure are investigated together by the complete diagonalization (of energy matrix) method (CDM). The obtained results are in reasonable agreement with the experimental ones. More importantly, two magnetically nonequivalent centers in YF3 crystal observed in EPR experiments are confirmed and ascribed to their specific positions in a unit cell by our calculations based on superposition model (SPM) analysis. Such identification of local sites with different magnetic properties would help us to understand not only the EPR spectra and magnetic susceptibility of other lanthanide ions doped in crystals with the same structure as YF3 but also the energy transfer scheme between two lanthanide ions occupying such two sites. All results are discussed carefully.

  10. EPR and optical absorption studies of VO2+ doped L-alanine (C3H7NO2) single crystals

    International Nuclear Information System (INIS)

    VO2+ doped L-alanine (C3H7NO2) single crystals and powders are examined by electron paramagnetic resonance (EPR) and optical absorption spectroscopy. Three magnetically different sites are resolved from angular variations of L-alanine single crystal EPR spectra. In some specific orientations each VO2+ line splits into three superhyperfine lines with intensities of 1:2:1 and maximum splitting value of 2.23 mT. The local symmetries of VO2+ complex sites are nearly axial. The optical absorption spectra show three bands. Spin Hamiltonian parameters are measured and molecular orbital coefficients are calculated by correlating EPR and optical absorption data for the central vanadyl ion.

  11. Demonstration through EPR tests of the sensitivity of austeno-ferritic steels to intergranular corrosion and stress corrosion cracking

    International Nuclear Information System (INIS)

    Duplex stainless steels can be sensitised to intergranular corrosion and stress corrosion cracking (SCC) under some conditions (heat treatments, welding). The aim of this work is to contribute to the validation of the EPR (Electrochemical Potentiodynamic Reactivation) test in order to determine conditions for normalisation. This method, based on the dissolution of chromium depleted areas due to precipitation of σ-phase, provides a degree of sensitisation to intergranular corrosion. The test is broaden considering the mechanical stress by the way of slow strain rate tests, performed in chloride magnesium and in a solution similar to the EPR solution. A metallurgical study puts on the precipitates and the structural modifications due to welding and heat treatments, in order to make a critical analysis of the EPR test. (author)

  12. EPR Study of Free Radicals in Cotton Fiber for Its Potential Use as a Fortuitous Dosimeter in Radiological Accidents

    International Nuclear Information System (INIS)

    Electron paramagnetic resonance (EPR) spectroscopy was applied to characterize radiation- induced free radicals in cotton fiber in order to determine the possibility for using cotton as a fortuitous dosimeter in accidental exposures to radiation. Cotton fabrics were irradiated at 0.1, 0.5, 1, 2, 10, 50 and 500 Gy using a 60Co gamma source. The irradiated samples were then stored in the dark under controlled environmental conditions for 1, 15, 35 and 60 days. The EPR spectra were observed in samples using a Bruker EMX X-band spectrometer equipped with a TE102 rectangular cavity. The EPR signal intensities of irradiated samples were determined from peak-to-peak amplitudes of EPR spectra and compared to unirradiated samples. The following optimum parameters were used: modulation frequency,100 kHz; microwave frequency, 9.84 GHz; modulation amplitude, 1.8 mT; microwave power,1.0 mW; time constant, 665 ms; conversion time, 41 ms; and sweep time, 41.98 s. The EPR spectra of unirradiated samples show a singlet line with g = 2.006 due to stable organic radicals pre-existing in the cotton fibers, whereas those of irradiated samples show the same pattern with different signal intensities according to the doses. Irradiation increased the signal intensity in a dose dependent manner. The signal intensity exhibited an exponential decay with storage time from 1 to 60 days. Obviously, the degree of fading of EPR intensity did not depend on the absorbed dose from 0.1-50 Gy. The maximum fading was about 60% at 60 days storage of irradiated samples at all doses. However the post-irradiation signal appeared to be detectable up to 60 days after irradiation. The results indicate the potential of using cotton as a fortuitous dosimeter in radiological accidents.

  13. Dosimetry of an accident in mixed field (neutrons, photons) using the spectrometry by electronic paramagnetic resonance(EPR)

    International Nuclear Information System (INIS)

    In a radiological accident, the assessment of the dose received by the victim is relevant information for the therapeutic strategy. Two complementary dosimetric techniques based on physical means are used in routine practice in the laboratory: EPR spectroscopy performed on materials removed from the victim or gathered from the vicinity of the victim and Monte Carlo calculations. EPR dosimetry, has been used successfully several times in cases of photon or electron overexposures. Accidental exposure may also occur with a neutron component. The aim of this work is to investigate the potentiality of EPR dosimetry for mixed photon and neutron field exposure with different organic materials (ascorbic acid, sorbitol, glucose, galactose, fructose, mannose, lactose and sucrose). The influence of irradiation parameters (dose, dose rate, photon energy) and of environmental parameters (temperature of heating, light exposure) on the EPR signal amplitude was studied. To assess the neutron sensitivity, the materials were exposed to a mixed radiation field of experimental reactors with different neutron to photon ratios. The relative neutron sensitivity was found to range from 10% to 43% according to the materials. Prior knowledge of the ratio between the dose in samples measured by EPR spectrometry and organ or whole body dose obtained by calculations previously performed for these different configurations, makes it possible to give a first estimation of the dose received by the victim in a short delay. The second aim of this work is to provide data relevant for a quick assessment of the dose distribution in case of accidental overexposure based on EPR measurements performed on one or several points of the body. The study consists in determining by calculation the relation between the dose to the organs and whole body and the dose to specific points of the body, like teeth, bones or samples located in the pockets of victim clothes, for different external exposures corresponding

  14. para palmito

    Directory of Open Access Journals (Sweden)

    Francisco Paulo Chaimsohn

    2007-01-01

    Full Text Available Densidades de siembra, arreglos espaciales y fertilización en pejibaye (Bactris gasipaes cv Diamantes-10 para palmito. La investigación se llevó a cabo en la Estación Experimental Los Diamantes (Guápiles, Costa Rica, el 3 de octubre del 2003, cuyo objetivo fue la evaluación del efecto de diferentes densidades de siembra (3.333, 5.000 y 6.666 plantas/ha, arreglos espaciales, y diversos métodos de fertilización (química, orgánica, sobre el crecimiento de las plantas de pejibaye para producción de palmito. Se consideraron las variables diámetro y altura del tallo primario y el número de hojas y rebrotes como indicadores de producción. El período de evolución abarcó sólo los primeros 25 meses de crecimiento en el campo. El número de hojas, la altura y el diámetro del tallo no mostraron diferencias de respuesta relevantes. Sólo el número de rebrotes disminuyó al aumentar la densidad de la población, cuando se midió a los 15 meses de edad. El efecto de la fertilización se hizo evidente después de la primera cosecha, realizada a los 20 meses, debido al aumento de la competencia entre plantas, ahora más desarrolladas. Fue entonces cuando la fertilización química indujo la producción de un mayor número y vigor de los rebrotes. Sin embargo, las prácticas evaluadas 25 meses después de la siembra, no habían infl uido hasta ese momento en el número de palmitos cosechados, ni tampoco había afectado las características físicas de los sectores foliar y caulinar del palmito.

  15. Economical opportunities on advanced conventional island design for the European pressurized water reactor (EPR) based on Konvoi design. Annex 6

    International Nuclear Information System (INIS)

    Design of the European Pressurized Water Reactor (EPR) has been finalized by the end of 1998. In parallel with these efforts, the German utilities group contracted the Siemens AG Power generation Group (KWU) to develop an advanced and optimized conventional island for the EPR. The main objectives for improving the conventional island design were determined on the basis of experience of the Konvoi series plants and advanced fossil plants. This paper describes the innovations introduced to the conventional island and presents the reasons for the resultant cost reductions. (author)

  16. EPR and SQUID studies on magnetic properties of SiO2-doped Ni-Zn ferrite nanocomposites

    International Nuclear Information System (INIS)

    Effects of the silica content and temperature on the magnetic properties of Ni0.5Zn0.5Fe2O4/SiO2 nanocomposites have been studied by electron paramagnetic resonance (EPR) and superconducting quantum interference device (SQUID) technique. The content of TEOS in the starting solution affects the interaction between NiZn ferrite and silica, and then determines the particle size and the EPR properties. In addition, the SQUID properties of the composites were sensitive to particle size. It was observed that the saturation magnetization (M s), remnant magnetization (M r) and initial susceptibility (χ i) decreased with increasing SiO2 content

  17. Para Leer

    Directory of Open Access Journals (Sweden)

    Adela Sanz Cañibano

    2012-01-01

    Full Text Available Jorge L. Tizón, Ramón Ciurana, M del Carmen Fernández (Comps. Libro de casos. Promoción de la salud mental desde la atención primaria. (Adela Sanz Cañibano Grupo de Expertos en Competencia Intercultural. Instrumento para la valoración de la Competencia Intercultural en la Atención en salud mental. Hacia la equidad en salud. (María Goretti Morón Nozaleda Mariano Hernández Monsalve y Pilar Nieto Degregori (Coords.. Psicoterapia y Rehabilitación de pacientes con psicosis. (Francisco Chicharro Lezcano André du Laurens. De las enfermedades melancólicas. Jourdain Guibelet. Del humor melancólico. (Iñaki Markez Julio José? Segarra Valls. Léxico psico(patológico en la obra de Carlos Castilla del Pino. (Eudoxia Gay Pamos Giorgio Nardone y Alessandro Salvini. El diálogo estratégico. (Fernando Mansilla Izquierdo Michel Foucault. Leçons sur la volonté de savoir, suivi de Le savoir d'Edipe. (Mauricio Jalón Camilo Castelo Branco. La novela de un hombre rico. (Alicia Merisi Kenzaburo Oé. Cuadernos de Hiroshima. (Mauricio Jalón Pascal Quignard. Les solidarités mystérieuses. (Beatriz A. Rubín Documentos en la red (Juan Medrano

  18. Oxidation state of manganese in zinc pyrophosphate: Probed by luminescence and EPR studies

    International Nuclear Information System (INIS)

    Zn2P2O7: Mn was synthesized by wet chemical route and characterized by X-ray diffraction (XRD), photoluminescence (PL) and electron paramagnetic resonance (EPR) techniques. Photoluminescence spectrum shows two bands, one at 500 nm (green emission), which is attributed to the 4T1(4G)-6A1(6S) transition of Mn2+ and other centered at 686 nm (red emission) is attributed to the electronic transition between 2E and 4A2 of Mn4+ accompanied with vibronic transitions. EPR spectroscopic studies also confirmed the presence of both Mn2+ and Mn4+ ions in zinc pyrophosphate with difference in the number of fine transitions and g values (Mn4+, S=3/2, three fine transitions and g 2+ S=5/2, five fine transitions and g=2.00).Mn2+ is attributed to presence of Mn at 6-ccordinated Zn2+ site whereas Mn4+ is due to presence substitution of Mn4+ at Zn2+ site thereby invoking charge compensation by presence of interstitial oxygen ions around Mn4+ ion or due to substitution of manganese at distorted 5-coordinated zinc site

  19. Integrity of the reactor coolant boundary of the European pressurized water reactor (EPR)

    Energy Technology Data Exchange (ETDEWEB)

    Goetsch, D.; Bieniussa, K.; Schulz, H.; Jalouneix, J.

    1997-04-01

    This paper is an abstract of the work performed in the frame of the development of the IPSN/GRS approach in view of the EPR conceptual safety features. EPR is a pressurized water reactor which will be based on the experience gained by utilities and designers in France and in Germany. The reactor coolant boundary of a PWR includes the reactor pressure vessel (RPV), those parts of the steam generators (SGs) which contain primary coolant, the pressurizer (PSR), the reactor coolant pumps (RCPs), the main coolant lines (MCLs) with their branches as well as the other connecting pipes and all branching pipes including the second isolation valves. The present work covering the integrity of the reactor coolant boundary is mainly restricted to the integrity of the main coolant lines (MCLs) and reflects the design requirements for the main components of the reactor coolant boundary. In the following the conceptual aspects, i.e. design, manufacture, construction and operation, will be assessed. A main aspect is the definition of break postulates regarding overall safety implications.

  20. Fast dynamic electron paramagnetic resonance (EPR) oxygen imaging using low-rank tensors

    Science.gov (United States)

    Christodoulou, Anthony G.; Redler, Gage; Clifford, Bryan; Liang, Zhi-Pei; Halpern, Howard J.; Epel, Boris

    2016-09-01

    Hypoxic tumors are resistant to radiotherapy, motivating the development of tools to image local oxygen concentrations. It is generally believed that stable or chronic hypoxia is the source of resistance, but more recent work suggests a role for transient hypoxia. Conventional EPR imaging (EPRI) is capable of imaging tissue pO2in vivo, with high pO2 resolution and 1 mm spatial resolution but low imaging speed (10 min temporal resolution for T1-based pO2 mapping), which makes it difficult to investigate the oxygen changes, e.g., transient hypoxia. Here we describe a new imaging method which accelerates dynamic EPR oxygen imaging, allowing 3D imaging at 2 frames per minute, fast enough to image transient hypoxia at the "speed limit" of observed pO2 change. The method centers on a low-rank tensor model that decouples the tradeoff between imaging speed, spatial coverage/resolution, and number of inversion times (pO2 accuracy). We present a specialized sparse sampling strategy and image reconstruction algorithm for use with this model. The quality and utility of the method is demonstrated in simulations and in vivo experiments in tumor bearing mice.