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Sample records for aportando piezas al

  1. Plaguicidas en la dieta: aportando piezas al rompecabezas Pesticides in the diet: adding pieces to the puzzle

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    Ángel Vicente

    2004-12-01

    Full Text Available Objetivos: Mejorar la información sobre la exposición a plaguicidas mediante la dieta en nuestro país con la presentación de los resultados de detección de 88 parámetros de plaguicidas en 1.109 muestras de alimentos, obtenidas entre 1998 y 2003 para el programa de Investigación de la Calidad Sanitaria de los Alimentos (ICSA de Barcelona. Material y método: Se presentan los resultados por grupos de alimentos y se comparan con la situación en el período anterior para frutas y hortalizas. La significación de las diferencias observadas se estima mediante la prueba de la χ². Resultados: En las 1.109 muestras analizadas se obtuvieron 116 resultados positivos para plaguicidas (10,5%. En el 1,5% de las muestras se detectaron halogenados persistentes y en el 14,4%, otros plaguicidas. Los positivos se concentran en frutas, hortalizas, especias y cereales y sus derivados. No hay positivos entre los aceites vegetales, los huevos ni los productos de la pesca, y casi no hay en los lácticos ni en los cárnicos. Las frutas concentran la mayor presencia de plaguicidas, en todos los casos no persistentes. Las hortalizas tienen menos plaguicidas, pero en ellas se detecta algún tipo de organoclorado. Al comparar los valores en las frutas y verduras con los de 1989-1997 no se aprecian diferencias que alcancen la significación estadística. Conclusiones: Aunque el volumen de muestras con plaguicidas es relevante, en su mayoría no son por productos halogenados persistentes. Destaca la elevada presencia de plaguicidas en la fruta.Objectives: To improve information on exposure to pesticides through diet in Spain by reporting the results on 88 pesticide parameters in 1,109 food samples obtained between 1998 and 2003 as part of the Barcelona program for research on the health quality of foods. Material and method: The results are presented by food groups. For fruits and vegetables, the results were compared with those for the previous period. Statistical

  2. Equipo de fusión al vacío para la determinación cuantitativa del gas atrapado en piezas fundidas

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    Hernández-Ortega, J. J.

    2009-02-01

    Full Text Available Parts manufactured with casting processes may trap substantial quantities of gas, which could harm the mechanical properties of the manufactured parts. In this work, a vacuum melting device manufactured to measure trapped gas in castings is described. Adjustment correlations, which accurately calculate trapped gas quantity as a function of the pressure increments measured by the vacuum equipment, are obtained. Finally, as an application of the equipment, we present the results obtained for several parts manufactured using a pressure die casting machine. It is expected that the vacuum melting device will be useful to optimize the operating conditions which reduce the trapped gas in casting processes.

    Las piezas obtenidas mediante procesos de fundición pueden contener cantidades importantes de gas ocluido, lo que podría afectar negativamente a las propiedades mecánicas de las piezas fabricadas. En este artículo se describe un equipo de fusión al vacío fabricado para la determinación de la cantidad de gas ocluido en piezas obtenidas mediante procesos de fundición. Se han obtenido correlaciones de ajuste que permiten el cálculo, con un buen grado de precisión, de la cantidad de gas ocluido en piezas fundidas en función de los incrementos de presión detectados por el equipo de vacío. Finalmente, se presentan, como aplicación del equipo, los resultados obtenidos en piezas fabricadas en una máquina industrial de fundición por inyección a presión. Se espera que el equipo desarrollado sea de gran utilidad para optimizar las condiciones de operación que reduzcan el aire atrapado en procesos de fundición.

  3. Propiedades mecánicas bajo compresión y resistencia al desgaste abrasivo de piezas gruesas de caucho acrilonitrilo

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    Sandra Milena Velásquez-Restrepo

    2015-09-01

    Full Text Available Se estudió la variación de las propiedades mecánicas bajo compresión uniaxial y el desgaste abrasivo en la sección transversal de piezas gruesas de caucho acrilonitrilo (NBR reforzadas con negro de humo, teniendo en consideración que en este tipo de piezas las propiedades obtenidas durante la vulcanización no son homogéneas, debido a la baja difusividad térmica de los cauchos. Se realizaron ensayos de desgaste abrasivo en seco, buscando identificar la relación entre la resistencia al desgaste abrasivo y las propiedades mecánicas en compresión, como el módulo elástico y la dureza. Se evaluaron muestras en estado de entrega tras el proceso de vulcanización, luego expuestas al ambiente durante tres meses y, posteriormente, envejecidas en una cámara UV. El envejecimiento ambiental rigidiza los materiales estudiados, pero disminuye la resistencia al desgaste del material proveniente del núcleo de las piezas. El envejecimiento UV disminuyó el módulo elástico, pero su efecto sobre la resistencia al desgaste depende del estado de envejecimiento previo. La dureza no presentó una relación directa ni con el módulo elástico ni con la resistencia al desgaste, por lo cual no puede usarse como propiedad para la selección de cauchos NBR sometidos a desgaste abrasivo. La información obtenida permite generar criterios para el diseño de componentes basados en este tipo de cauchos.

  4. Empleo de la cáscara de arroz en la fundición de piezas de acero al carbono//Using of rice husk in the carbon steel casting parts process

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    Juan Carlos Cruz-Pérez; Jesús Eduardo González-Ruiz; Lorenzo Perdomo-González; Pantaleón Rodríguez-González

    2012-01-01

    Los materiales auxiliares desempeñan un papel importante en el aumento de la eficiencia tecnológica del proceso de fundición de piezas de acero al carbono. En este artículo se exponen los primeros resultados del empleo de la cáscara de arroz como material termoaislante en la obtención de piezas fundidas de acero al carbono. En los experimentos se evaluó la influencia  de seis combinaciones de las variables espesor de pared del casquillo y capa de cobertura. En la confección de los casquillos ...

  5. De la apología al triste cantar: la evaluación de la Conquista de México en las piezas teatrales de John Dryden (1667 y Fernando de Zárate (1668

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    Ana Núñez-Ronchi

    2012-07-01

    Full Text Available ResumenLa (representación de la conquista de América ha sido objeto creciente deestudio en los distintos ámbitos lingüísticos nacionales. Sin embargo, son pocos los estudios que se han interesado por la escenificación teatral de la Conquista desde una perspectiva comparativa. Recurriendo al aparato teórico-metodológico de la semántica interpretativa, este trabajo se propone comparar la visión inglesa y la española de la conquista de México en dos piezas de teatro europeas contemporáneas y presumiblemente basadas en las mismas fuentes históricas, "The Indian Emperour" de John Dryden (1667 y "La Conquista de México" de Fernando de Zárate (1668. Nuestra interpretación mostrará cómo, a pesar de sus similitudes, estas piezas presentan soluciones y evaluaciones divergentes respecto de los acontecimientos que escenifican.Palabras clave: comedia española - drama heroico - semántica interpretativa- conquista de MéxicoAbstractCriticism has been paying increased attention to the (representation of the Conquest of America in several national domains. Nevertheless, few studies encompass the theatrical depiction of the Conquest of Mexico from a comparative perspective. In accordance with textual semantics, this studyproposes to compare the Spanish and the English vision of the Conquest of Mexico in two contemporary and presumably historically-based works, John Dryden’s "The Indian Emperour" (1667 and Fernando de Zárate’s "La Conquista de México" (1668. Our interpretation will show that, despite their similarities, each work presents differing evaluations of the Conquestof Mexico.Keywords: Spanish Comedia - heroic drama - interpretative semantics - Conquest of Mexico

  6. Empleo de la cáscara de arroz en la fundición de piezas de acero al carbono//Using of rice husk in the carbon steel casting parts process

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    Juan Carlos Cruz-Pérez

    2012-05-01

    Full Text Available Los materiales auxiliares desempeñan un papel importante en el aumento de la eficiencia tecnológica del proceso de fundición de piezas de acero al carbono. En este artículo se exponen los primeros resultados del empleo de la cáscara de arroz como material termoaislante en la obtención de piezas fundidas de acero al carbono. En los experimentos se evaluó la influencia  de seis combinaciones de las variables espesor de pared del casquillo y capa de cobertura. En la confección de los casquillos se utilizó cáscara de arroz triturada, la que posteriormente fue aglutinada con silicato de sodio, apisonada y endurecida con CO2, mientras que la cobertura se utilizó sin procesamiento previo. El mayor nivel de entrega de acero se obtuvo al emplear un espesor de casquillo de 65 mm y una altura de cobertura de 85 mm. El valor del ASAF generado por las variantes experimentales resultó igual o inferior a 0,48. Palabras claves: casquillo termoaislante, polvo de cobertura, cáscara de arroz, acero fundido.______________________________________________________________________________ Abstract Feeding auxiliary materials perform a very important role in improves technological efficiency of carbon steel casting parts process. In this article are exposing the first results in the rice husk using as an insulating material in such process. The variables sleeve thickness and covering thickness’ influence were evaluated in six combinations by means of experiments. In sleeves preparation was used crushed rice husk, which was agglutinated with sodium silicate, compacted and hardened with CO2, meanwhile as covering it was uses without previous preparation. The mayor liquid steel delivering level was get employing 65 mm sleeve thickness and 85 mm covering thickness. The ASAF value generated for experimental variants was equal or inferior to 0.48. Key words: insulating sleeve, riser sleeve, hot topping, rice husk, steel cast.

  7. Conservación y elaboración de piezas anatómicas con sustancias diferentes al formol en la Facultad de Ciencias Agropecuarias de la Universidad de La Salle

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    César Alfonso Muñetón Gómez

    2011-12-01

    Full Text Available El presente estudio, realizado en el área de Anatomía, se basó en la búsqueda de una alternativa diferente al formol para la conservación de piezas anatómicas, teniendo en cuenta sustancias menos agresivas con el medioambiente, y buscando una disminución en el número de animales destinados para el estudio anatómico. Por otra parte, se realizó el diseño y la elaboración de modelos anatómicos en diferentes materiales como yeso, acrílico, látex y resinas para su utilización como herramienta didáctica en el proceso enseñanza-aprendizaje de la asignatura; así mismo, se dio inicio a la plastinación de algunos órganos a fin de permitir su conservación y estudio de la forma más natural posible.

  8. La lógica del bricolaje y las piezas sueltas

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    Barandiarán, Agustín

    2015-01-01

    Jacques Alain Miller, en la primera clase de su curso Piezas sueltas (2013), a la que titula “Bricolaje” (2013: 9-26), nos remite a la lectura del primer capítulo de El pensamiento salvaje (1964), cuyo autor es Claude Lévi Strauss, para referirse al lazo existente entre el ángulo estructuralista y la pieza suelta. Dando cuenta a su vez de lo heteróclito de la estructura, que sin embargo suele representársenos como un sistema uniforme, homogéneo. Esta no es la única referencia que Miller cita ...

  9. Comportamiento del acabado superficial de la pieza y el desgaste de la herramienta al fresar aluminio con altas velocidades de corte en fresadoras cnc convencionales. // Superficial finish behavior and tool wear in aluminium milling with high cutting spee

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    F. Martínez Aneiro

    2006-05-01

    Full Text Available La demanda de componentes mecánicos de alta calidad y gran exactitud para sistemas de elevado desempeño estaaumentando considerablemente en los últimos años a nivel mundial. Este hecho ha provocado el desarrollo de nuevastecnologías aplicadas a los procesos de corte.El desarrollo integral de las máquinas herramientas (controles, husillos de alta velocidad de las herramientas de corte(nuevos materiales para los substratos y capas y de la tecnología de maquinado posibilitó la aplicación del corte con altasvelocidades de corte (High speed Cutting HSC. El aumento de las velocidades de corte es una de las formas de aumentar laeficiencia de los procesos productivos a través de la reducción de los tiempos de fabricación. La reducción en varias vecesde los tiempos de fabricación, se logra no solo por los tiempos de maquinado sino también por la sustitución o minimizarotros procesos de elaboración que forman parte de la cadena productiva, los cuales en ocasiones son relativamente lentoscomo son la electroerosión, el acabado manual en la producción de moldes y troqueles así como los cambios deoperaciones de la pieza.Por ser un proceso relativamente nuevo, introduciéndose a partir de la década de los años 90 aun existen muchas cuestionestecnológicas que están sin respuesta. Es interés del presente trabajo, mostrar los efectos de las altas velocidades de cortesobre la vida útil de la herramienta y el acabado superficial en la pieza, trabajando en máquinas fresadoras de CNC¨convencionales¨. Los resultados muestran que dentro de los parámetros estudiados la durabilidad de la herramienta y elacabado superficial mejoran y que el comportamiento de la máquina es estable a pesar de no estar concebida para el nuevoconcepto de altas velocidades.Palabras Claves: Altas velocidades de corte, HSC, HSM desgaste, acabado superficial.______________________________________________________________________________Abstract.The demand of

  10. Desarrollo de la automatización de un sistema de clasificado y procesado de piezas con monitorización y control mediante pantalla táctil

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    PAÑOS MORENO, ALBERTO

    2016-01-01

    [ES] Desarrollo de la automatización de un proceso de clasificación y procesado de piezas, formado por un sistema de transporte de piezas mediante cintas transportadoras y cilindros neumáticos de succión mediante ventosa, en el que se han implementado diversos modos de funcionamiento. La detección del tipo de pieza se lleva a cabo por medio de un sensor fotoeléctrico. Para efectuar la automatización del sistema, debido al gran número de entradas y salidas digitales del proceso, se...

  11. Fabricación de piezas de fundición con grafito esferoidal en molde metálico

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    Urrestarazu, A.

    2013-10-01

    Full Text Available The features and suitability of high requirements ductile iron castings production using metallic moulds have been studied in the present work. The structural and mechanical properties of the produced castings have been analysed and compared to the corresponding ones but fabricated using green sand moulds according to a conventional production process. The higher cooling rate in the metallic moulds is the main cause for the appearance of the detected structural changes in castings. The mechanical and microstructural properties obtained directly on castings are remarkable due to the higher nodule count among other factors. Finally, the benefits and inconveniences found in this kind of production methodology using metallic moulds are also discussed.En este trabajo se estudia el empleo de moldes metálicos o permanentes para la fabricación de piezas de fundición esferoidal con elevados requerimientos funcionales y se analizan sus propiedades, comparándolas con piezas obtenidas utilizando moldes de arena de sílice, de acuerdo con las metodologías más habituales para este tipo de procesos. La elevada velocidad de solidificación y el posterior enfriamiento rápido de la austenita formada en estado sólido se erigen como los principales factores diferenciadores que originan las modificaciones estructurales detectadas en las piezas. Las propiedades físicas, mecánicas y microestructurales obtenidas directamente sobre pieza son destacables debido, entre otros aspectos, al gran número de esferoides grafíticos obtenidos en las piezas. Se discuten también las ventajas e inconvenientes encontrados en esta metodología de producción que emplea moldes fabricados con una aleación metálica específica.

  12. Diseño del molde para la inyección de una pieza de plástico

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    Pérez Indurain, Pablo

    2010-01-01

    El objetivo de este proyecto es el diseño de un molde para inyección de plásticos cuyo fin sea la producción en serie de un obturador, pieza clave para las cámaras de fotos analógicas. Debido a la complejidad geométrica de la pieza, se procederá al estudio en profundidad de la inyección y posterior enfriamiento del plástico en la cavidad por medio del programa de simulación por elementos finitos Moldflow. Mediante la modificación de los diferentes parámetros que intervienen ...

  13. EL MUSEO KOLUMBA: ELOGIO DE LA PIEZA AUSENTE

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    Virginia Navarro Martínez

    2010-05-01

    Full Text Available RESUMEN El presente artículo trata de profundizar, a través del estudio del museo Kolumba, en algunos condicionantes específicos que posee el proyecto que debe trabajar con arquitecturas del pasado, destacando entre ellos el modo en el que el objeto de partida queda incluido y contenido en el resultado final. La realidad última que el edificio construye, mediante la interpretación de lo preexistente, es el espacio invisible de la memoria (la pieza ausente. Las intervenciones llevadas a cabo a raíz de la destrucción de la iglesia de Santa Columba en la Segunda Guerra Mundial hasta la inauguración del presente museo nos permiten entender el proyecto de Zumthor como la culminación de una trayectoria iniciada años atrás por Rudolf Schwarz con la reconstrucción de Colonia. La sensibilidad y la convergencia interpretativa de los sucesivos autores que en este espacio intervienen originan una lectura conjunta que trasciende la personalidad individual de cada uno de ellos. Se tratará también en este artículo de la obra de tres artistas, presentes en el museo, especialmente vinculados a la memoria del sitio y de la destrucción desde ópticas y modos creativos diferentes: Ulrich Tillman, Bill Fontana y Richard Serra.SUMMARY Through the study of the Kolumba Museum, the article attempts an in–depth study of some specific determinants that the plan must have in order to work with architectures from the past, emphasising the way in which the initial objective is encompassed in the final result. Through the interpretation of the pre–existing, the final reality that the building constructs is the invisible space of the memory (the missing piece. The interventions carried out as a result of the destruction of the church of Santa Columba in World War II until the inauguration of the present museum, allow us to understand Zumthor’s plan as the culmination of a process begun years ago by Rudolf Schwarz with the reconstruction of Cologne. The

  14. Recondicionamiento de piezas de hierro fundido por tratamiento térmico (II Parte

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    Francisco Luis Hernández Arias

    2008-01-01

    Full Text Available Se aborda la importancia que posee el incremento de volumen del material, en piezas de hierro gris, a causa de los cambios estructurales que en las mismas provoca el tratamiento térmico; planteándose como objetivo fundamental el de mostrar que el tratamiento térmico no solamente es aplicado a piezas en el proceso de fabricación, sino que es posible su aplicación en el proceso de recuperación de piezas; escogiéndose como problema, el desgaste que sufren algunos elementos del motor de combustión interna (MCI, como son los segmentos y los sombreretes o tapetas del tractor KOMATSU, debido a la fricción que sufren estos elementos. Se muestra además la tecnología de recuperación tratamiento térmico empleada.

  15. Distribución y corte de piezas irregulares con anidamiento bidimensional en la industria minera

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    José Arzola-Ruíz

    2010-03-01

    Full Text Available La necesidad del ahorro de material durante el corte de piezas en chapas ha provocado el desarrollo de procedimientos y técnicas de optimización, con la ayuda de las nuevas tecnologías de la informática y las comunicaciones. A pesar de la existencia de diversas plataformas automatizadas para la generación de distribuciones y rutas de corte, el ahorro de material constituye un indicador de permanente atención en la industria minera. En el presente trabajo se ilustra el estado actual del desarrollo de las técnicas de distribución y corte de piezas en chapas y se define la concepción de un procedimiento para la distribución de piezas irregulares con anidamiento bidimensional.

  16. Análisis ergonómico de puestos de trabajo en fábrica de moldeado de piezas de plástico

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    Herrera, Patricia

    2012-01-01

    Para la realización de este proyecto voy a estudiar los puestos de trabajo de una fábrica de piezas moldeadas de plástico perteneciente al convenio de la química en la que se identificarán los riesgos ergonómicos asociados a varios puestos de trabajo, y a las zonas generales cumpliendo con la reglamentación vigente. Se evaluarán los riesgos detectados y se propondrán métodos preventivos para disminuir, evitar o eliminar dichos riesgos en la medida de lo posible. La ergonomía es una acti...

  17. Recondicionamiento de piezas de hierro fundido por tratamiento térmico (I Parte

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    Maria Elvira Font Pérez

    2008-01-01

    Full Text Available Se recoge una breve panorámica sobre la importancia que posee el incremento de volumen de material, en piezas de hierro fundido, a causas de los cambios estructurales que en las mismas provoca el tratamiento térmico. Se escoge como problema el desgaste que sufren algunos elementos del motor de combustión interna debido a la fricción, así como su recuperación empleando este método. Por otro lado se realiza un análisis a cerca de como influyen sobre las propiedades mecánicas principales de estos elementos, los factores principales del régimen del tratamiento térmico aplicado en su recuperación. Se dan las ventajas, que sobre otros métodos, posee el tratamiento térmico en el recondicionamiento de piezas de hierro fundido.

  18. Diseño y desarrollo de troquel para conformar una pieza de chapa

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    López Soto, Jaime

    2011-01-01

    Duración (en horas): Más de 50 horas. Nivel educativo: Grado El proyecto completo consiste en el diseño de una pieza de chapa, y el diseño y desarrollo del troquel para conformar la pieza. Se trata de un proyecto real que muestra una actividad muy habitual en el ámbito de la ingeniería. Las habilidades que se desarrollan son: búsqueda de información, definición del problema, diseño conceptual, selección de alternativas, diseño de detalle, desarrollo de producto, análisis de producto, p...

  19. Diseño de un molde de inyección de una pieza pástica

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    Fernández Barroso, Janire Begoña

    2014-01-01

    El objeto del proyecto es el diseño un molde de inyección para la fabricación de una pieza plástica para el sector de la automoción. El cliente, solicita la fabricación de una pieza plástica que servirá como montante lateral de un vehículo. Para ello, define el diseño de la pieza y las características que debe cumplir. Con el diseño de la pieza concebido y las características exigidas, se decide fabricar mediante molde por inyección. El proyecto consistirá en el diseño del m...

  20. Piezas muebles bajomedievales pertenecientes a la iglesia parroquial de Santiago de La Coruña

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    Barral Rivadulla, María Dolores

    1995-12-01

    Full Text Available Not available.

    Este trabajo tiene como intención fundamental rescatar parte del patrimonio perteneciente a la iglesia parroquial de Santiago de La Coruña, producción artística, tradicionalmente omitida, pero de gran importancia si se intenta analizar a través de la misma la religiosidad y el mundo que las rodea, como piezas manifestación de determinada devoción o creencia.

  1. Estructuras livianas a partir de piezas menores de madera de plantación

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    Aldo Ramírez Coretti

    2007-05-01

    Full Text Available Se presentan los resultados de un estudio exploratorio, parte de una serie de investigaciones conjuntas desarrolladas y en proceso de desarrollo, alrededor de esta temática. Su ejecución respondió, entre otras, a inquietudes presentadas por diversos productores de madera deplantación. El estudio consideró el diseño y fabricación de una máquina espigadora de piezas estructurales. También procuró explorar el potencial de aprovechamiento de piezas producto de raleos de madera de plantación para la fabricación de estructuras livianas. Se llevaron a cabo ensayos de uniones, de marcos simples con dos paneles de cerramiento comerciales, empleando cuatro especies de madera de plantación. También se llevó a cabo la fabricación de las piezas y montaje de una estructura modelo, empleando el equipo y otra información obtenida como resultado de la investigación. Los resultados muestran un gran potencial para el desarrollo de un sistema de construcción ágil y modular. Asimismo, las resistencias obtenidas sonadecuadas para las condiciones a que estarían expuestas las estructuras.

  2. Evaluación del grado de adecuación del proceso de forja en caliente para la fabricación de piezas estampadas: criterios de viabilidad y optimización

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    Arenas Reina, José Manuel

    2000-10-01

    Full Text Available The design of industrial parts is a clear example of integrative effort that, with a focus of several disciplines, requires a detailed analysis of the different scientific and technological knowledge implied in its conception and development. Inside this performance context, the present work approaches the problem of the project of hot forging parts, proposing the use of criteria of viability and optimization that, based in technical and economical considerations, allow to value the adjusting degree of various alternative to the forge process, facilitating with it the selection of the most appropriate. Fixed these bases and with object of shortening times of answer and analysis in an application corresponding to parts with revolution symmetry, a computerized system has been introduced that, taking as started data the design of the part, geometrically simulates the forge process, allowing to calculate the adaptation coefficients in those morphologing that are possible according to the criteria of viability criteria. This system also provides a graphic representation of machined part, the forged part and the finished stamp.

    El diseño de piezas industriales supone un claro ejemplo de esfuerzo integrador que, con un enfoque interdisciplinar, requiere un análisis detallado de los diferentes conocimientos científicos y tecnológicos implicados en su concepción y desarrollo. Dentro de este marco de actuación, el presente trabajo aborda la problemática del proyecto de piezas estampadas en caliente, proponiendo la utilización de criterios de viabilidad y optimización que, fundamentados en consideraciones técnico-económicas, permiten valorar el grado de adecuación de las diferentes alternativas al proceso de forja, facilitando con ello la selección de la más adecuada. Fijadas estas bases y con objeto de acortar tiempos de respuesta y análisis en una aplicación correspondiente a piezas axisimétricas, se ha introducido un sistema

  3. Educación inclusiva y diversidad funcional: Conociendo realidades, transformando paradigmas y aportando elementos para la práctica

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    Leidy Evelyn Díaz-Posada

    2016-01-01

    Full Text Available El presente artículo presenta los resultados de una investigación documental cuyo objetivo fue poner en evidencia indicadores relacionados con las realidades y la puesta en práctica de la educación inclusiva así como las transformaciones en el tiempo respecto al uso del lenguaje para referirse a la población con diversidad funcional y la detección de experiencias exitosas de inclusión para esta población. Se encontró que el enfoque que promueve la adopción del término “Diversidad Funcional”, como sustitutivo de “discapacidad”, es tendencia a nivel internacional en tanto se propone como una corriente de lenguaje y pensamiento que contribuye a la transformación de representaciones sociales desfavorables que hasta hoy se han transmitido con relación al objeto de estudio. Por su lado, se realiza una conceptualización de la educación inclusiva, acompañada de la identificación de sus factores determinantes y de pautas para la generación de contextos y procesos inclusivos de calidad, desde una perspectiva práctica.

  4. Algunas soluciones de estructuras de hormigón armado formadas por piezas premoldeadas

    Directory of Open Access Journals (Sweden)

    Fisac, Miguel

    1963-04-01

    repetición sea suficientemente amplia y, con ello, la ventaja económica se deje sentir respecto de otros métodos constructivos que no utilizan estos elementos previamente preparados; pero, actualmente, se presta gran atención a las formas arquitectónicas, lo cual requiere que las piezas o elementos prefabricados estén dentro del juego dimensional que un despiece de la forma exige. Pero este problema presenta su dificultad, porque la concepción de la forma, tiene como origen la resistencia y estabilidad, a los que estos elementos han de acoplarse. Otro aspecto particular de estos elementos se conjuga con su propia estructura y susceptibilidad, con objeto de dejarse moldear dentro de un proceso de industrialización que le proporcione una clara ventaja sobre los otros materiales. El transporte, acopio y manipulación de estos elementos estructurales prefabricados presenta, asimismo, sus problemas, ya que, en general, su concepción para formar un todo puede ser perfecto sin que, por ello, al considerar aisladamente un elemento, éste resulte frágil. Respecto a su colocación en obra, son también necesarios ciertos elementos de enganche para las grúas o máquinas de elevación que los han de llevar a su posición definitiva. Como puede apreciarse, estos elementos, si han de ser real eficaces y prestar ayuda notable en las realizaciones de obra tipo civil o arquitectónico, deberán reunir ciertas exigencias más cuyo ajuste y alcance requerirán especial cuidado y el, problema éste que el autor emprende y trata, de desarrollar con la esperanza de contribuir a no pocas aspiraciones de campo en que ha entrado y pretende descubrir el indudable práctico sentido de la prefabricación.

  5. Implementación de un procedimiento metodológico para la elaboración de piezas por bruñido con rodillo simple.

    Directory of Open Access Journals (Sweden)

    S. Díaz Rojas,

    2009-01-01

    Full Text Available En el presente trabajo se exponen los fundamentos y los resultados de investigaciones realizadas sobre la operación secundaria de acabado superficial de piezas conocida como bruñido por rodillo simple.Se abordan teóricamente las cuestiones más importantes de los procesos de deformación plástica superficial empleados para el mejoramiento de las cualidades superficiales de las piezas.Se realiza una investigación experimental en piezas simétrico-rotativas de acero AISI 1045 en un torno paralelo convencional con una herramienta de bruñir mono rodillo construida al efecto, donde se toman en consideración las variables más influyentes en el bruñido por rodillo simple: fuerza compresiva, avance y número de pasadas de la herramienta bruñidora. Se obtienen los modelos empírico-matemáticos que describen los efectos de estas variables en el incremento de la dureza y la calidad superficial final de la pieza, así como en la disminución del diámetro exterior y en la profundidad de la capa endurecida. Como resultado más importante de este trabajo, se desarrolla un procedimiento metodológico para la elaboración de piezas mediante este tipo de tratamiento mecánico por deformación plástica superficial, que permitirá la creación y difusión de una disciplina tecnológica sobre un proceso de fabricación que posee ventajas y que está poco difundido en las empresas metalmecánicas.In the present work the foundations and the results of the investigation for the secondary operation of superficial finish (single roller burnishing are presented. The most important aspects of the superficial plastic deformation process for improving superficial finish are approachedAn experimental investigation in symmetrical-revolving pieces of steel AISI 1045 in a conventional parallel lathe with a burnishing tool of single roller built to the effect is carried out. The most influential variables were took in consideration: compressive force, feed and number

  6. Diseño de una unidad de proceso para el tratamiento superficial (cromado y niquelado) de piezas de acero para automoción

    OpenAIRE

    2012-01-01

    El proyecto se centra en la desmineralización continua de aguas residuales de lavado para su posterior reutilización en baños de tratamiento superficial de piezas de acero para automoción. Concretamente se centra en tratar un número máximo de 300000 piezas anuales, 75 piezas diarias. Tratando un volumen máximo de 16 m3/h de agua residual procedente de los baños de tratamiento superficial de piezas de acero.

  7. Una nueva pieza de artilleria de galeras del siglo XVI: el esmeril bastardo «matacapitanes»

    Directory of Open Access Journals (Sweden)

    Fondevila Silva, Pedro

    2012-12-01

    Full Text Available This work is aimed at the analysis of an unknown piece of maritime artillery dated at the second half of the XVIth century. This piece, out of any inventory record, was located within one of the Archive-Museum chambers in the Don Álvaro Bazán Palace at El Viso del Marqués, Ciudad Real province, central Spain. The specimen is a bastard esmeril here so-called «matacapitanes» («killer of captains» because it seems precisely designed to be used against the bullet-proof armour of enemy officers. By means of manuscripts and impressed documents, an approach and discussion on the typology and classification of the XVIth century´s maritime artillery is also presented.

    Trabajo de investigación que presenta y analiza una pieza desconocida de artillería naval de la segunda mitad del siglo XVI, localizada sin inventariar en una de las salas del Archivo-Museo «Don Álvaro de Bazán» del Palacio de El Viso del Marqués en Ciudad Real (España. Se trata de un esmeril bastardo que hemos bautizado como «matacapitanes », por ser un modelo diseñado para optimizar su empleo contra los oficiales enemigos protegidos con armaduras a prueba de balas de arcabuz. Además, se realiza una aproximación al estudio de la tipología y clasificación de la artillería naval del siglo XVI a través de los documentos, tanto manuscritos como impresos, de esa época.

  8. Interpretación en arqueología : piezas de collar de una necrópolis navarra

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    Amparo Castiela Rodríguez

    2005-01-01

    Full Text Available Los restos de ajuar, recuperados en la necrópolis que han seguido el rito de la cremación, nos llegan muy alterados y requieren en ocasiones un esfuerzo especial para su comprensión. En el caso de varias piezas procedentes de La Atalaya, que formaban parte de collares, cuya interpretación ofrecemos

  9. Composites de bagazo de baja densidad para partes y piezas moldeadas para la industria automotriz

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    Manuel Serantes

    2006-01-01

    Full Text Available Se desarrolló un composite a partir del bagazo de la caña de azúcar, con características similares a una muestra entregada por la firma FAIST GmbH& Co. K.G. de Alemania, para ser empleado en la elaboración de partes y piezas moldeadas para la industria automotriz. Se estudian diferentes grados de molida. A los composites obtenidos se le determinaron las propiedades físico-mecánicas. Se realizó un análisis visual de su aspecto físico. Se presentan los resultados obtenidos, así como conclusiones y recomendaciones.

  10. Simulación de una célula robotizada para la fabricación de piezas mecanizadas en un entorno industrial, utilizando RobotStudio

    OpenAIRE

    Muinelo Garrido, Gonzalo

    2015-01-01

    El trabajo consiste en la realización de la simulación de una célula robotizada, que servirá para el tratamiento de una pieza de aluminio mediante tres máquinas que estarán abastecidas por un robot central; este último será el encargado de gestionar la entrada y salida de piezas en las máquinas, y de realizar el intercambio de piezas entre máquinas, así como el gestionar la entrada y salida de piezas de la célula robotizada. La simulación se llevará a cabo con el programa RobotStudio, prop...

  11. Modelación por Elementos Finitos como Método para la Sustitución de Piezas de Acero por Hierro Nodular.

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    Mario Jacas

    2005-09-01

    Full Text Available Dado el nivel de aplicación que ha tenido en los últimos años la sustitución de piezas de acero por hierrofundido nodular, en este trabajo se establece una vía de análisis con el empleo de un software deElementos Finitos que justifique desde el punto de vista de las propiedades mecánicas de los elementoslas posibilidades de sustitución.El objetivo del presente trabajo es la sustitución de un tope de maquina hormigonera originalmentefabricado de componentes soldados de material AISI 1020 por uno rediseñado con hierro nodularaustemplado (ADI, utilizando la modelación por elementos finitos, sobre la base de un análisis linealestático.Finalmente, al comparar las tensiones de Von Mises y los desplazamientos originados por la acción de lacarga, se pudo observar un mejor comportamiento mecánico en el modelo rediseñado del tope de hierronodular austemplado (ADI.

  12. La prospección de superficie en la caracterización de yacimientos: poblado protohistórico de Pieza Redonda en Lanciego (País Vasco

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    Rodríguez Fernández, J., Martínez Montecelo, A.

    2015-01-01

    Full Text Available Hoy día, nadie duda de la eficacia de la prospección superficial como herramienta de valoración, gestión y preservación del patrimonio arqueológico. Sin embargo, su verdadero alcance analítico y cognoscitivo no queda tan claro en la distinta bibliografía existente al respecto. Basándonos en la experiencia obtenida en el yacimiento de Pieza Redonda (Lanciego, Álava, el artículo pretende impulsar una reflexión en torno a las posibilidades, problemáticas y desarrollo teórico-metodológico de la inspección visual dentro de la Arqueología, lo que conlleva necesariamente en nuestra opinión una revisión de conceptos tales como territorio, paisaje y yacimiento.

  13. Extracción y tipificación de ADN a partir de piezas dentales de muestras arqueológicas de la prov. de Santa Cruz

    OpenAIRE

    Cristian M. Crespo; Dejean, Cristina Beatriz; Carnese, Francisco R.; Lanata, José Luis

    2009-01-01

    A partir de la década del ´90, en diversas investigaciones se logró obtener ADN a partir de piezas arqueológicas. Estos estudios paleogenéticos han ayudado a resolver diferentes interrogantes relacionados con modelos de poblamiento de distintas áreas: migraciones, movimientos poblacionales, patrones demográficos y estudios sobre la dieta de las poblaciones originarias. En el presente trabajo se logró extraer ADN a partir de piezas dentales de 3 individuos provenientes del Museo Regional Rosa ...

  14. Prefactibilidad proyecto de construcción de una planta de estampado de piezas metálicas en Renault - SOFASA

    OpenAIRE

    Londoño Velásquez, Santiago; Raigoza Toro, Cristóbal

    2014-01-01

    Este estudio pretende evaluar la prefactibilidad de implantar un proceso de estampado de piezas para el proceso de fabricación de vehículos en Renault-Sofasa, teniendo en consideración las piezas más representativas en costo logístico y tamaño -- Para esto se evalúan los diferentes estudios como lo son el análisis del sector, estudio de mercado, técnico, organizacional, legal, económico y, finalmente, se plantea un plan de gestión del proyecto -- Para la realización de estos estudios se tomar...

  15. Identificación de asimetrías bilaterales en piezas y cortes porcionados comerciales de canales de bovino procesadas en Guadalajara, Jalisco, México

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    J. M. Zorrilla

    2011-01-01

    Full Text Available Se identifica la presencia de asimetrías entre el lado izquierdo y el derecho en canales de bovino faenadas en el Rastro Municipal de Guadalajara, Jalisco (México, a partir de la comparación de tres piezas primarias, 30 porcionados comerciales y siete componentes anatomo-estructurales, diferencias agrupadas arbitrariamente en un origen de carácter anatómico, de índole mecánico por el proceso físico de su división y la posible combinación de ambos. El análisis de los datos generados de 20 canales permitió identificar que el riñón, la grasa de la riñonada y el sebo fueron estructuras anatómicas con pesos estadísticamente diferentes (P<0.0178; P<0.0183; P<0.0944, respectivamente cuando se compararon los correspondientes pares izquierdo y derecho. La bandera, el contrapecho, el diezmillo, el pescuezo y el recoveco fueron cortes porcionados estadísticamente diferentes (P<0.0005; P<0.0817; P<0.0859; P<0.0387; P<0.0178, respectivamente cuyo origen se puede adjudicar a factores anatómicos y, posiblemente, mecánicos al momento de su separación física. La única estructura estadísticamente diferente (P<0.0001 entre ambos lados -considerada producto de una influencia de la operación mecánica durante su separación- fue el cuarto anterior de la canal. Estos resultados apoyan la sugerencia de establecer un solo lado de la canal de bovinos en la implementación de normas y sistemas de clasificación, por calidades y rendimientos.

  16. Implementación de un procedimiento metodológico para la elaboración de piezas por bruñido con rodillo simple // Implementation of a methodological procedure for parts elaboration by single roller burnishing.

    Directory of Open Access Journals (Sweden)

    S. Díaz-Rojas

    2009-01-01

    Full Text Available En el presente trabajo se exponen los fundamentos y los resultados de investigaciones realizadas sobrela operación secundaria de acabado superficial de piezas conocida como bruñido por rodillo simple.Se realiza una investigación experimental en piezas simétrico-rotativas de acero AISI 1045 en un tornoparalelo convencional con una herramienta de bruñir mono rodillo construida al efecto, donde setoman en consideración las variables más influyentes en el bruñido por rodillo simple: fuerzacompresiva, avance y número de pasadas de la herramienta bruñidora. Se obtienen los modelosempírico-matemáticos que describen los efectos de estas variables en el incremento de la dureza y lacalidad superficial final de la pieza, así como en la disminución del diámetro exterior y en laprofundidad de la capa endurecida. Como resultado más importante de este trabajo, se desarrolla unprocedimiento metodológico para la elaboración de piezas mediante este tipo de tratamientomecánico por deformación plástica superficial, que permitirá la creación y difusión de una disciplinatecnológica sobre un proceso de fabricación que posee ventajas y que está poco difundido en lasempresas metalmecánicas.Palabras claves: bruñido por rodillo simple, deformación plástica superficial, dureza superficial, rugosidadsuperficial, acero AISI 1045.___________________________________________________________________________AbstractIn the present work the foundations and the results of the investigation for the secondary operation ofsuperficial finish (single roller burnishing are presented. The most important aspects of the superficialplastic deformation process for improving superficial finish are approachedAn experimental investigation in symmetrical-revolving pieces of steel AISI 1045 in a conventionalparallel lathe with a burnishing tool of single roller built to the effect is carried out. The mostinfluential variables were took in consideration: compressive

  17. Metodología para el cálculo de espesores límite libres de fase sigma durante el hipertemple en piezas de aceros dúplex de gran sección

    Directory of Open Access Journals (Sweden)

    Jimbert, P.

    2013-04-01

    embargo, al aumentar la profundidad a la que se encuentran los yacimientos actuales, los espesores para este tipo de canalizaciones se han visto incrementados, lo que se traduce en mayores niveles de exigencia sobre todo su proceso de fabricación, incluyendo el tratamiento térmico. Para evitar la precipitación de estas fases intermetálicas, como la fase sigma, es necesario conocer el perfil de enfriamiento en el centro de la pieza y para ello, conocer el valor del Coeficiente de Transferencia de Calor Superficial (h es fundamental. Dicho coeficiente varía durante el hipertemple y su valor se determina experimentalmente ya que depende de varios parámetros del proceso. Diversos estudios demuestran que su valor se estabiliza a los pocos segundos, por lo que para conocer el perfil de enfriamiento en el centro de grandes secciones bastaría con conocer el valor estabilizado de h. Sin embargo, los estudios existentes en la literatura se refieren a diámetros menores de 100 mm. En el presente trabajo se ha desarrollado una metodología para predecir la precipitación de fases intermetálicas en piezas de acero dúplex con grandes espesores en instalaciones industriales a partir del cálculo de h. Esta metodología nos permite calcular los perfiles de enfriamiento sin sacrificar ninguna pieza, utilizando una o varias piezas patrón sensorizadas con termopares y una simulación posterior mediante ANSYS.

  18. Salvar al soldado Ryan con 300 espartanos: historia, memoria, mito

    OpenAIRE

    Pérez García, Juan Carlos

    2012-01-01

    El presente artículo tiene por objeto indagar en los temas de la construcción de la memoria, el mito y la tradición oral, tal como se han proyectado en dos películas recientes de gran impacto internacional, principalmente 300 (2007, Zack Snyder) y Salvar al Soldado Ryan (1998, Steven Spielberg). También pretendemos explorar las innovaciones que las técnicas del nuevo cine digital están aportando a estas mitologías contemporáneas. The present paper addresses the issues of construction of me...

  19. El intestino: pieza clave del sistema inmunitario The bowel: A key component of the immune system

    Directory of Open Access Journals (Sweden)

    E. Ramiro-Puig

    2008-01-01

    Full Text Available El intestino se halla expuesto constantemente a una elevada carga antigénica procedente de la dieta y de bacterias comensales. El tejido linfoide asociado al intestino (Gut-Associated Lymphoid Tissue, GALT constituye la parte más extensa y compleja del sistema inmunitario y es capaz de discriminar de forma eficaz entre patógenos invasivos y antígenos inocuos. El conocimiento de su particular subdivisión en tejido organizado, inductor de la respuesta inmunitaria (placas de Peyer y ganglios linfáticos mesentéricos, y tejido difuso, efector de la respuesta inmunitaria (linfocitos intraepiteliales y linfocitos de lámina propia, nos permite comprender cómo se desarrolla y regula la respuesta inmunitaria en el intestino y como esta puede extenderse al resto del organismo.The gut is constantly exposed to a high antigenic load coming from the diet and commensal bacteria. The Gut-Associated Lymphoid Tissue (GALT constitutes the most extensive and complex part of the immune system and is capable of efficiently distinguishing invasive pathogens from innocuous antigens. The knowledge of its unique structure consisting on organised tissue, inductor of the immune response (Peyer's patches and mesenteric lymph nodes, and diffused tissue, effector of the immune response (intraepithelial lymphocytes and lamina propria lymphocytes, allow us to understand the development and regulation of the immune response in the gut and how this one can be extended to the rest of the organism.

  20. Piezas de arte tradicional a través de pantallas

    Directory of Open Access Journals (Sweden)

    Panozzo Zenere, Alejandra

    2014-01-01

    Full Text Available [es] El objetivo de este artículo es reflexionar sobre la producción de sentido al contemplar una obra de arte desde un espacio físico y a través de una pantalla. Esta problemática será analizada a partir de la pérdida de materialidad en un tipo de producción tradicional que se conforma como imagen digital, y le permite ser reproducida a través del dispositivo mencionado.Se trata de señalar, cómo el arte de caballete u objetual se conforma como un nuevo producto artístico a causa de las lógicas que plantea la digitalización.

  1. Recubrimiento de superficies arquitectónicas con piezas cerámicas

    OpenAIRE

    Vacca Jaren, María Celina

    2010-01-01

    La hipótesis principal de esta investigación se basa en la demostración de la importancia que ha adquirido España con respecto al material cerámico tanto en fabricación, puesta en obra y su uso en la arquitectura haciendo un estudio histórico desde la Revolución Industrial hasta nuestros días. A través de la observación de la historia veremos como este material usado como revestimiento en la arquitectura, ha superado altibajos en su utilización debido a la banalización de su uso, a veces r...

  2. Experiencias en Cuba de la producción de piezas fundidas de fundición gris esferoidal (FGE, un material de elevadas cualidades y propiedades.

    Directory of Open Access Journals (Sweden)

    Francisco Mondelo García

    2005-09-01

    Full Text Available El trabajo expone alternativas posibles de acceder a fabricar fundiciones grises esferoidales(FGE, así como conocimientos, experiencias y métodos empleados en su producción en Cuba,contando por lo tanto con un material de elevadas cualidades y propiedades tecnológicas enexplotación. Se dan materiales básicos utilizados en los procesos de obtención de la FGE, locual incluye el proceso de recarburación de estas aleaciones ferrosas, más las operaciones denodulización e inoculación, junto a los controles bases en sus operaciones fundamentales, parafabricar piezas con la calidad y certificación requeridas. Se tienen resultados experimentalesproductivos de estas fundiciones nodulares, con marcas de diversas estructuras, propiedadesmecánicas y composiciones. Se valora además resultados de la sustitución de piezas deaceros por FGE con posibilidades de obtener, por tratamiento térmico los hierrosaustemperados (ADI y elementos económicos comparativos de la factibilidad de fabricación dela fundición sintética en piezas FGE con chatarras de aceros básicamente y recarburantesnacionales de carbón vegetal, como variante alternativa.

  3. Caracterización de hierros sinterizados fabricados con virutas procedentes de la mecanización de piezas sinterizadas

    Directory of Open Access Journals (Sweden)

    García-Cambronero, L. E.

    2005-02-01

    Full Text Available The objective of the present work is the iron swarfs reusing as raw material to manufacture sintered parts. Particle size reduction using Horizontal attrition milling within iron dilution is the way used to get the raw materials. Two powder mixtures were obtained: Commercial Iron+50 % milled swarfs, and the milling mixture of iron+50 %swarfs. After powder characterization, the powder mixtures were die pressing and sintering at 1150 -C during 30min under N2-5 %H2 atmosphere. Density and dimensional change were determined on sintered materials. Also mechanical properties were obtained. Influence on properties from Microstructure and powder sinter ability were analyzed.

    La aplicación de las virutas de hierro como materia prima en la fabricación de piezas sinterizadas es el objetivo de presente trabajo. Su incorporación como materia prima se plantea a través de su reducción en tamaño, junto con su dilución con polvos de hierro mediante la utilización de un molino horizontal de alta energía. Los polvos obtenidos corresponden a dos mezclas: polvos de hierro comercial con 50 % de virutas molidas y polvos de una mezcla hierro+50 % viruta que han sido conjuntamente molidos. Las mezclas de polvos se caracterizaron, se consolidaron en matriz rígida y se sintetizaron a 1.150 °C durante 30 min en atmósfera de N2-5 %H2. Además de la determinación de la densidad o variación dimensional de los materiales sinterizados, se determinaron sus propiedades mecánicas. Finalmente, se analizo la influencia de la microestructura obtenida y la sinterabilidad de las mezclas de polvos obtenidos con estas propiedades.

  4. Estudio de la transformación martensítica, optimización de la microestructura y prevención de la rotura frágil en piezas coladas de acero X38CrMoV5-1 de alta resistencia

    OpenAIRE

    Pastor Muro, Ana

    2015-01-01

    La presente tesis trata sobre el "Estudio de la transformación martensítica, optimización de la microestructura y prevención de la rotura frágil en piezas coladas de acero X38CrMoV5-1 de alta resistencia”. El acero X38CrMoV5-1/AISI H11 es un acero martensítico al cromo-vanadio-molibdeno para trabajo en caliente fácilmente endurecible, que se fabrica generalmente por moldeo con la consiguiente presencia de porosidad interdendrítica. La primera parte de la tesis consiste en una introducción don...

  5. La fase del Ibérico final en el asentamiento del Torrelló del Boverot (Almazora, Castellón: dos piezas cerámicas singulares

    Directory of Open Access Journals (Sweden)

    Clausell, Gerardo

    2000-12-01

    Full Text Available Since the end of 1988, when excavation was resumed at the Torrelló del Boverot site in Almazora (Castellón, large amounts of material —mostly ceramics— have been recovered, dating from the end of the Iberian period, which, chronologically, marked the end of the village's life. This paper discusses two unusual ceramic pieces from this late period, documented during the excavations that took place in 1995, undertaken in the central area of the site. The records obtained in this work matches that of a batch of materials donated to the Museum of Almazora by the amateurs who excavated this village in the mid-1970s.Desde finales de 1988, cuando se retoman las campañas de excavación en el yacimiento del Torrelló del Boverot de Almazora (Castellón, se recuperaron abundantes materiales —fundamentalmente cerámicos— del periodo Ibérico final que cierra cronológicamente la vida del poblado. En este trabajo presentamos dos piezas cerámicas singulares correspondientes a esta fase tardía, documentada a través de la campaña de excavación llevada a cabo en 1995, en la que se trabajó en el área central del asentamiento. El registro obtenido en esta intervención coincide con el proporcionado por un lote de materiales donados al Museo de Almazora por parte de los aficionados que excavaron este poblado a mediados de la década de los setenta.

  6. « On travaille à la seconde! » Rémunération à la pièce et santé et sécurité du travail dans une perspective qui tient compte de l’ethnicité et du genre “We work by the second!” Piecework remuneration and occupational health and safety from an ethnicity- and gender-sensitive perspective «Trabajamos al Segundo!» Remuneración por pieza y salud y seguridad en el trabajo en una perspectiva que toma en cuenta la etnicidad y el género

    Directory of Open Access Journals (Sweden)

    Karen Messing

    2008-05-01

    Full Text Available Peu d’études qualitatives ont décrit les mécanismes par lesquels le travail à la pièce influence la santé. Nous présentons les résultats de 25 entrevues réalisées entre 2004 et 2006 dans une grande entreprise de fabrication de vêtements à Montréal. Nous décrivons la main- d’œuvre, constituée en grande majorité de femmes et d’immigrants, les exigences et contraintes de production, les stratégies des travailleurs et travailleuses favorisant la production et celles favorisant la santé, et la gestion et l’impact des problèmes de santé vécus au travail. De plus, nous confrontons la réalité du travail à la pièce à la représentation que s’en font différents intervenants (employeurs, travailleurs, travailleuses décideurs, médecins telle qu’elle a été rapportée dans 62 décisions sur des réclamations pour lésion professionnelle rendues par la Commission des lésions professionnelles (C.L.P. entre 2000 et 2007, décisions portant sur l’industrie du vêtement et mentionnant le travail à la pièce. Nous examinons les causes et discutons des implications de nos résultats.Few qualitative studies have described the mechanisms by which piecework influences health. We present the results of 25 interviews conducted between 2004 and 2006 in a large garment factory in Montreal. We describe the workforce, made up in large part of women and immigrants, the requirements and constraints of production, workers’ strategies favouring production and those favouring health, and the management and impact of the health problems experienced by workers. In addition, we compare the experience of piecework to its representation by various stakeholders (employers, workers, decision-makers, doctors as reported in 62 decisions regarding compensation claims for work-related health problems rendered by the Commission des lésions professionnelles (C.L.P. between 2000 and 2007, decisions pertaining to the garment industry and

  7. “We work by the second !” Piecework remuneration and occupational health and safety from an ethnicity- and gender-sensitive perspective « On travaille à la seconde ! » Rémunération à la pièce et santé et sécurité du travail dans une perspective qui tient compte de l’ethnicité et du genre « Trabajamos al Segundo ! » Remuneración por pieza y salud y seguridad en el trabajo en una perspectiva que toma en cuenta la etnicidad y el género

    Directory of Open Access Journals (Sweden)

    Karen Messing

    2008-05-01

    Full Text Available Few qualitative studies have described the mechanisms by which piecework influences health. We present the results of 25 interviews conducted between 2004 and 2006 in a large garment factory in Montreal. We describe the workforce, made up in large part of women and immigrants, the requirements and constraints of production, workers’ strategies favouring production and those favouring health, and the management and impact of the health problems experienced by workers. In addition, we compare the experience of piecework to its representation by various stakeholders (employers, workers, decision-makers, doctors as reported in 62 decisions regarding compensation claims for work-related health problems rendered by the Commission des lésions professionnelles (C.L.P. between 2000 and 2007, decisions pertaining to the garment industry and mentioning piecework. We examine the causes and discuss the implications of our results.Peu d’études qualitatives ont décrit les mécanismes par lesquels le travail à la pièce influence la santé. Nous présentons les résultats de 25 entrevues réalisées entre 2004 et 2006 dans une grande entreprise de fabrication de vêtements à Montréal. Nous décrivons la main- d’œuvre, constituée en grande majorité de femmes et d’immigrants, les exigences et contraintes de production, les stratégies des travailleurs et travailleuses favorisant la production et celles favorisant la santé, et la gestion et l’impact des problèmes de santé vécus au travail. De plus, nous confrontons la réalité du travail à la pièce à la représentation que s’en font différents intervenants (employeurs, travailleurs, travailleuses décideurs, médecins telle qu’elle a été rapportée dans 62 décisions sur des réclamations pour lésion professionnelle rendues par la Commission des lésions professionnelles (C.L.P. entre 2000 et 2007, décisions portant sur l’industrie du vêtement et mentionnant le travail à la

  8. Influencia de la formulación de la arena en verde en su difusividad térmica y su efecto en una pieza colada

    Directory of Open Access Journals (Sweden)

    Noguez, M. E.

    2005-12-01

    Full Text Available Data evidencing a relation among green sand formulations (% water/% bentonite, w/b, in the ranks 0.2-0.55 for 6, 7, 8 and 9 % bentonite, their heat transfer behaviour, specifically their thermal diffusivity, the casting solidification rate and the resulting macrostructures in aluminium castings are presented.

    Se presentan evidencias de que la formulación de una arena en verde (relación entre los porcentajes de agua y de bentonita, a/b, en el rango 0,2-0,55 para 6, 7, 8 y 9 % de bentonita parece determinar su transferencia de calor y, por tanto, su coeficiente de difusividad térmica, lo que influye en la rapidez de solidificación y en las macroestructuras de piezas coladas en aluminio.

  9. Una visión analítica gramatical-musical de las piezas para piano de Adolfo Mejía

    OpenAIRE

    Zambrano Rodríguez, Leonardo

    2012-01-01

    Este trabajo pretende determinar las técnicas de escritura utilizadas por el compositor colombiano Adolfo Mejía en la composición de sus piezas para piano. Esta es una tarea que requiere de una descripción analítica de los procesos y técnicas de composición utilizados; para ello se debe recurrir a los análisis armónico, formal, contrapuntístico y rítmico de estas obras. Este tipo de estudios está relacionado con el estilo de composición, para comprenderlo, es válido abordarlo de manera indivi...

  10. Prototipo de herramienta para el inventariado automático de piezas de Lego basado en visión artificial

    OpenAIRE

    Rodríguez Garrido, Alberto Jesús

    2014-01-01

    Permitida la difusión del código bajo los términos de la licencia BSD de tres cláusulas. [ES] Se presenta un prototipo de herramienta para la detección, segmentación, clasificación y conteo de piezas Lego basado en la librería de visión artificial OpenCV. Este prototipo surge ante la necesidad de automatizar la compleja y tediosa tarea del inventariado de kits Lego de la serie MindStorm. En el proceso de detección y segmentación se han utilizado técnicas de umbralizado y el algoritmo de se...

  11. Microscopios del siglo XVIII del Museo Nacional de Ciencias Naturales. CSIC. Dos piezas únicas de la Ilustración para la investigación naturalista

    Directory of Open Access Journals (Sweden)

    González-Alcalde, Julio

    2010-10-01

    Full Text Available The objective of this work is to make a journey the history, characteristics and process of restoring of two of the oldest pieces in the Collection of the Technology and Industrial Archeology from the National Museum of Natural Sciences. CSIC. They are two microscopes from the eighteenth century, built in England. The simple-compound microscope, built by George Adams around 1750-1770, might have belonged to Don Antonio de Ulloa or Don Pedro Franco Dávila. Only two similar pieces are displayed in the Science Museum in Geneva and London. The compound microscope, built by Dollond in the 1780s, was owned by Eugenio Izquierdo de Rivera y Lazaún successor of D. Pedro Franco Dávila in the direction of the Royal Cabinet of Natural History. He was a well-known naturalist as well as a judge, diplomat, secretary and informant of Manuel Godoy.

    El objetivo de este trabajo es efectuar un recorrido por la historia, características y proceso de restauración de dos de las piezas más antiguas de la Colección de Arqueología de la Técnica e Industrial del Museo Nacional de Ciencias Naturales. CSIC. Son dos microscopios del siglo XVIII, construidos en Inglaterra. El microscopio simple-compuesto, construido por George Adams hacia 1750-1770 pudo pertenecer a D. Antonio de Ulloa o a Don Pedro Franco Dávila. Sólo se exponen dos piezas semejantes en el Museo de la Ciencia de Ginebra y en el de Londres. El microscopio compuesto, construido por Dollond hacia 1780, fue propiedad de Eugenio Izquierdo de Rivera y Lazaún sucesor de D. Pedro Franco Dávila en la dirección del Real Gabinete de Historia Natural, actual Museo Nacional de Ciencias Naturales. Era un conocido naturalista y, además, juez, diplomático, secretario e informante de Manuel Godoy.

  12. Piezas de mobiliario y decoración en escayola intarsiada, firmadas por Antonio y Vicente Marzal

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    Gutiérrez Pastor, Ismael

    2009-03-01

    Full Text Available A first approach to the study of inlay plasterwork (Italian scagliola in Spain, and the Marzal brothers, Valencian artists active during the first half of the 19th century who worked for Carlos IV and Fernando VII.

    Primera aproximación al estudio de la escayola (“scagliola” en España y a los hermanos Marzal, artistas valencianos de la primera mitad del siglo XIX que trabajaron para los reyes Carlos IV y Fernando VII.

  13. Estudio Experimental de Piezas Lineales de Hormigón Reforzadas con Fibras de Carbono Experimental Study of Reinforced Concrete Beams Strengthened with Carbon Fibers

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    M. Valcuende

    2004-01-01

    Full Text Available Se ha estudiado el comportamiento de seis vigas reforzadas simultáneamente con láminas y tejidos de fibra de carbono. Se analiza, para este tipo de refuerzos, la validez de dos de los métodos de cálculo posiblemente más utilizados. En ambos métodos se plantean las ecuaciones de equilibrio de fuerzas y momentos, pero se introducen suposiciones diferentes: i el acero tiene suficiente capacidad plástica para no romperse y ii el agotamiento se produce siempre por rotura de la lámina. Los resultados obtenidos ponen de manifiesto que refuerzos de láminas y tejidos de fibra de carbono influyen notablemente sobre las piezas, mejorando su capacidad portante y modificando su comportamiento estructural en cuanto a rigidez y ductilidadA study on the behaviour of six beams reinforced with carbon fiber laminates and fabrics was done. The validity of the two most commonly used methods of evaluating the effects of these reinforcements was analyzed. Both methods propose equilibrium equations based on forces and moments, although introducing two different suppositions: i that the steel posesses enough elasticity to avoid breakage, and ii failure is always produced by the breakage of the laminate. The results obtained demonstrate that carbon fiber laminates and fabric reinforcements have notable influence on the pieces, improving their loading capacities and modifying their structural behavior regarding stiffness and ductility

  14. Asimetría de piezas de canales de bovino faenadas en el rastro municipal de Guadalajara, Jalisco, México

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    R. J. M. Zorrilla

    2010-01-01

    enteros, procesados en el rastro municipal de Guadalajara, Jalisco, México. Como criterio de evaluación se adoptó el grado de desviación de un valor de uno del coeficiente de correlación de Pearson del producto-momento. Los resultados mostraron la posible existencia de asimetrías de índole anatómico entre el lado derecho y el izquierdo de la cantidad de grasa de la riñonada y grasa pélvica, así como el área del ojo de la costilla, las cuales mostraron una correlación de 0.7102, 0.7704, 0.7649, respectivamente. Estos coeficientes de correlación son inferiores a los obtenidos para la comparación de los pesos de los segmentos derecho e izquierdo delanteros y traseros, de 0.9705 y 0.9587, respectivamente; lo que permite suponer que en las condiciones en que se llevó a cabo el presente trabajo, el proceso mecánico de cuarteo de las canales no alteró la simetría entre las piezas. Se señalan las posibles implicaciones que estos factores pueden tener en la construcción de un modelo matemático de predicción de cortabilidad de una canal de bovino.

  15. El mobiliario de “mosaico vegetal” para Isabel II. El despacho de la reina y otras piezas

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    Sancho Gaspar, José Luis

    2011-06-01

    Full Text Available Luxury furnishings of exceptional quality preserved in state institutions have long been considered to have been gifts of the Monarchs, and particularly of Isabel II. The authors here resolve the origin, manufacture and vicissitudes of one of these groups made for the office of the Queen in the Madrid Royal Palace, but currently located in the Supreme Court.

    Muebles de lujo y especial calidad conservados en instituciones estatales han venido siendo considerados como regalos de los monarcas, y en especial de Isabel II. Se resuelve aquí el origen, fabricación y vicisitudes de uno de estos conjuntos destinado al despacho de la reina en el Palacio Real de Madrid y localizado en el Tribunal Supremo.

  16. Formación de grafito chunky en piezas de pequeño espesor fabricadas utilizando fundición de hierro con grafito esferoidal

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    Asenjo, I.

    2011-10-01

    Full Text Available Chunky graphite is a degenerated graphite form which can be found in the thermal centre of ductile iron heavy section castings. Previous studies made on cubic blocks (300 and 180 mm in side manufactured using alloys with fully ferritic matrix structures show that low cooling rates, excessive post-inoculation and high silicon and/or cerium contents in the melts are the most important factors that promote this kind of defect. The enhancement of these critical factors led to obtain chunky graphite in sections lower than 50 mm. Different experimental conditions have been used in order to establish the main parameters that affect this graphite malformation. The use of cutting-edge techniques in the analysis of chemical compositions has revealed that no significant differences can be found when comparing chunky areas and well-formed spheroidal graphite areas. On the other hand, it has not been possible to establish any correlation between the oxygen contents and the scale of the defect. However, it is noteworthy that the oxygen content is related to the use of magnesium or cerium as nodulizer agent.

    El grafito chunky es una malformación detectada habitualmente en las zonas de última solidificación pertenecientes a piezas de fundición grafítica esferoidal con enfriamientos muy lentos. Estudios previos realizados sobre bloques cúbicos de 300 y 180 mm de lado y fabricados con aleaciones de matriz ferrítica, indican que los factores que promueven la formación de este defecto son: bajas velocidades de enfriamiento, excesiva post-inoculación del metal de colada y la presencia de elevados contenidos de silicio y/o cerio. La intensificación de estos factores en la fabricación de piezas con espesores más reducidos ha permitido obtener grafito chunky en secciones inferiores a 50 mm. Se han utilizado diferentes condiciones experimentales y se han determinado los factores de mayor influencia en la formación del defecto. La utilización de t

  17. Construcción de una maquina de control numérico " CNC" para prototipado rápido de piezas 3D en diferentes polímeros "impresora 3D"

    OpenAIRE

    Sanjuan Mauriz, Oscar

    2014-01-01

    El objetivo principal del presente Proyecto Fin de Carrera es la construcción , montaje y calibración de una impresora 3D auto replicable modelo Prusa Mendel capaz de trabajar en coordenadas polares, lo cual abre las puertas a la investigación de calidades, tolerancias, resistencias estructurales… de estas piezas en comparación con las fabricadas por impresoras cartesianas. Encontraras una guía de montaje paso a paso, además de un listado de todos los componentes, imprimibles y no imprimibles...

  18. La audiencia previa al juicio en el modelo procesal civil español

    OpenAIRE

    Gascón Inchausti, Fernando; Palomo Vélez, Diego

    2007-01-01

    El trabajo analiza con detalle una de las piezas clave del nuevo proceso civil español, la audiencia previa al juicio. Se trata de una vista oral que ha de celebrarse en los juicios ordinarios una vez que las partes ya han presentado por escrito su demanda y su contestación, y que tiene una finalidad múltiple: conciliadora, depuradora de vicios procesales, delimitadora del objeto del proceso y del debate y preparatoria del acto del juicio en sí, a través de la proposición y admisión de las pr...

  19. El uso de técnicas de Simulación para la predicción de defectos en piezas fundidas. // The use of simulation techniques for the prediction of defects in casting parts.

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    T. Rodríguez Moliner

    2004-09-01

    Full Text Available El uso de técnicas de simulación para predecir defectos en piezas fundidas es una técnica ampliamente difundida en elmundo. Esto conlleva grandes ahorros de tiempo y recursos, además de aumentar la calidad de las piezas que se obtienen.Estas ventajas son ejemplificadas en el siguiente artículo mostrando las posibilidades del uso de este tipo de técnicas en elcampo de la tecnología de la fundición.Palabras Claves: simulación, solidificación, llenado del molde, rechupe.______________________________________________________________________________AbstractThe aim of the present paper is to show the evident advantages of using simulation techniques in foundry technologies. Theconsiderable save of time and economic resources that implies the use of this techniques has spread worldwide.As in Cuba the use is not extended to the foundries, we intend to demontrate the possibilities of the use of simulationsoftware for the development of casting technologies.Key words: simulation, solidification, mould filling, shrinkage.

  20. Optimización de los parámetros tecnológicos para la obtención de piezas de latón por pulvimetalurgia

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    Krivij, N.

    1995-12-01

    Full Text Available Powders of brass 60 (40 % Zn and brass 80 (20 % Zn have been produced by spraying molten metal with water at high pressure in the powder metallurgy plant belonging to the Metallurgical Research Centre (CIME in Havana. A physical-chemical and technological characterization of the powders has been carried out and the optimum parameters have been determined for the formation and sintering of details from these powders. The mechanical properties of these details can rival bronze and iron in applications such as in household electrical goods and in construction.

    Se han producido polvos de latón 60 (40 % de Zn y latón 80 (20 % de Zn mediante la atomización del metal fundido con agua a alta presión, en la planta de pulvimetalurgia del Centro de Investigaciones Metalúrgicas (CIME de La Habana. Se ha realizado la caracterización fisicoquímica y tecnológica y se han determinado los parámetros óptimos para conformar y sinterizar piezas a partir de estos polvos. Las propiedades mecánicas de estas piezas pueden competir con las de bronce y hierro, en aplicaciones para equipos electrodomésticos y en construcción.

  1. Determinación de los tiempos de retraso en gestión y búsqueda de piezas de repuesto de las cosechadoras de arroz en el Complejo Agroindustrial Arrocero "Los Palacios"

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    Erwin Herrera González

    2011-01-01

    Full Text Available Los tiempos de gestión y búsqueda de piezas de repuesto de las cosechadoras de arroz durante la cosecha es un indicador determinante para minimizar el tiempo de restablecimiento de la capacidad de trabajo de las máquinas una vez ocurrida la falla; por lo que se hace necesario aumentar la eficiencia del proceso. Durante el cálculo se tienen en cuenta los factores que influyen en las pérdidas de tiempo por retraso administrativo y logístico y así proponer las medidas para eliminar o disminuir los tiempos improductivos, asegurar la capacidad de trabajo de las cosechadoras y por tanto su productividad.

  2. Leyendo el sur. A propósito del libro Cantes al Amorsillega de Ginés Liébana

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    Bartolomé Delgado Cerrillo

    2011-06-01

    Full Text Available A través de los poemas del libro Cantes al Amorsillega de Ginés Liébana, haremos un recorrido por las principales coplas del cante flamenco, incidiendo en la personal interpretación que nos da el autor y aportando su relación con la significación de las formas poéticas y las imágenes con que las ilustra. Este libro es valioso para ser integrado en la educación reglada como producto cultural. Y es valioso no solo como portador de contenidos antropológicos, sociológicos, coreográficos, musicales, poéticos e históricos, sino también como compendio de los estereotipos culturales que caracterizan la identidad cultural andaluza.

  3. Método de obtención piezas extensas de altas prestaciones mecánicas y térmicas de vidrios de oxicarburo de silicio

    OpenAIRE

    Oteo Mazo, José Luis; Rubio Alonso, Juan; Rubio Alonso, Fausto; Mazo Fernández, María Alejandra

    2010-01-01

    La presente patente de invención está dirigida principalmente al sector automovilístico, aeronáutico y aeroespacial, así como otros sectores industriales en los cuáles se requieran materiales de alta resistencia mecánica y térmica.

  4. Fabrication and tribological properties of Al reinforced with carbon fibers

    Directory of Open Access Journals (Sweden)

    Estrems Amestoy, Manuel

    2000-10-01

    Full Text Available The present work studies the manufacturing process of Al reinforced with Carbon Fibres (CF by "Squeeze Casting", establishing the variables for obtaining an acceptable product with little Al4C3 at the interface. Friction and wear tests are performed and the necessary conditions for the formation of a tribofilm are established. The tests show an increasing resistance to abrasion due to their own wear mechanism. Certain design criteria for those components subjected to friction are recommended in order to maximise the mechanical performance of the tribological system.

    Este trabajo estudia el proceso de fabricación de composites Al reforzado con fibras de carbono mediante la técnica ''Squeeze Casting'', estableciendo las variables para obtener un producto aceptable que tenga poca cantidad de Al4C3 en la interfase. Se han realizado ensayos de fricción y desgaste y se han establecido las condiciones necesarias para la formación de la tribocapa. Se muestra la alta capacidad de resistencia a la abrasión de las piezas producidas debido a su propio mecanismo de desgaste y se recomiendan ciertos criterios de diseño para componentes mecánicos con el fin de optimizar las prestaciones mecánicas en un sistema tribológico.

  5. Aproximación al lenguaje de Olivier Messiaen: análisis de la obra para piano "Vingt Regards sur l'Enfant-Jésus"

    OpenAIRE

    Costa Ciscar, Francisco Javier

    2004-01-01

    Esta tésis tiene por objeto realizar una aproximación al lenguaje de Olivier Messiaen, a través del análisis de su obra para piano Vingt Regards sur l ´ Enfant - Jésus. El trabajo se centra en ofrecer una visión, una recreación de la obra desde la perspectiva analítico - musical, sin partir de métodos de análisis estereotipados sino obteniendo de cada una de las 20 piezas, de cada una de las Veinte Miradas aqu...

  6. Algoritmo GRASP para la programación de piezas de un sistema flowshop híbrido con pulmones intermedios limitados

    OpenAIRE

    Murio Fernández, Miguel

    2010-01-01

    Este proyecto final de carrera se ha enfocado al estudio de la programación de operaciones. En concreto, el problema que se analiza en profundidad es la estructura flowshop híbrido de máquinas. Esta configuración de máquinas consiste en un conjunto de máquinas dispuestas en serie entre etapas y en paralelo en cada una de ellas. Es decir, el flowshop híbrido consta de una serie de niveles de máquinas colocados uno a continuación del otro. En cada uno de estos niveles puede ex...

  7. Resultados preliminares sobre la estimación de la edad de muerte a partir de la evaluación de la estructura interna de piezas dentales uniradiculares

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    Luna, Leandro

    2005-01-01

    Full Text Available Se ha documentado que existe una importante correlación negativa entre la edad biológica y las dimensiones de la cavidad pulpar de incisivos, caninos y premolares. Esto se debe a que la depositación de la dentina secundaria en la superficie de la cavidad pulpar continúa con tasas más o menos constantes durante toda la vida del individuo. También se identificaron correlaciones entre edad de muerte y el desarrollo de la retracción periodontal y de la transparencia radicular. De esta manera, analizando la estructura interna de esas piezas dentales mediante inspecciones escópicas y radiográficas, es posible obtener información relevante para estimar las edades de muerte. Estos métodos han sido aplicados con éxito en investigaciones forenses, y deben ser puestos a prueba cuando la muestra proviene de un contexto arqueológico. En esta ponencia se presentan los primeros resultados de la evaluación de diferentes variables métricas en una muestra procedente del Sitio Chenque I (Parque Nacional Lihué Calel, provincia de La Pampa. Las edades de los individuos que componen la muestra fueron estimadas evaluando indicadores confiables como sínfisis púbica y superficie auricular, y luego comparadas con los resultados del análisis dental.

  8. ALS - resources

    Science.gov (United States)

    Resources - ALS ... The following organizations are good resources for information on amyotrophic lateral sclerosis : Muscular Dystrophy Association -- mda.org/disease/amyotrophic-lateral-sclerosis National Amyotrophic Lateral Sclerosis (ALS) Registry -- ...

  9. Evaluación de minerales alumino silicatos de Norte de Santander para fabricar piezas cerámicas de gran formato

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    Sandra Milena Rozo-Rincón

    2014-12-01

    Full Text Available Se dan a conocer los resultados de la influencia del feldespato al ser mezclado con arcilla del área metropolitana de Cúcuta (Norte de Santander, Colombia, en relación con las principales variables que son tenidas en cuenta a la hora de fabricar un producto cerámico tradicional de gran formato mediante técnica de conformado por extrusión. Los materiales empleados fueron arcillas provenientes de las formaciones León y Guayabo, y el feldespato del municipio de Sardinata, los cuales fueron estudiados mediante difracción de rayos (DRX y fluorescencia de rayos X (FRX. Las probetas conformadas se realizaron empleando proporciones de 100:0, 90:10 y 80:20 de arcilla-feldespato, respectivamente, y fueron sometidas a cocción a las temperaturas de 950°C-1000°C-1050°C. Se observó que la adición de feldespato mejoró de manera significativa las propiedades estudiadas para todas las arcillas empleadas en comparación con la mezcla patrón. Las muestras preparadas con arcilla Támesis presentaron el mejor desempeño.

  10. Pérdida de flúor en piezas dentarias permanentes expuestas a refrescos: estudio comparativo in vitro Fluor loss in permanent teeth exposed to beverages: Comparative study in vitro

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    P Núñez

    2006-04-01

    Full Text Available Introducción: La exposición a refrescos y zumos de frutas se encuentra en constante aumento, siendo su principal característica la elevada acidez que presentan. Con estas alteraciones del equilibrio oral, la perdida mineral de la estructura dentaria es muy frecuente. Nuestro objetivo fue identificar la cantidad de flúor perdido de una pieza dentaria y comparar el efecto de dos bebidas presentes en el mercado. Metodología: Se formaron dos grupos con 15 premolares cada uno, extraídos por indicación de ortodoncia; las piezas no presentaban patologías clínicas. El experimento consistió en la aplicación de un amortiguador de fuerza iónica para posteriormente llevarlo a una curva de calibración. Luego con un pH metro (ORION, modelo 920 A se obtuvo los datos de pH de las bebidas; luego, durante 30 minutos se sumergió en la respectiva bebida para que con el electrodo se obtuviera los resultados de flúor presente. Se realizo la prueba estadística T test para muestras independientes. Resultados: cada vez más estudios confirman el impacto de los ácidos en la cavidad oral y su papel en la erosión dentaria. En nuestro estudio se aprecio un pH de 3,1 para la bebida de naranja y 2,5 para la bebida cola. Además arrojo diferencia significativa de la pérdida de flúor según la bebida aplicada (pIntroduction: The exposure of soft drinks and fruit juices is constantly increasing and the main caracteristic of these beverages is the high acidity. This alteration of oral balance causes a more frequent loss of dental minerals. Our main objective was to identify the quantity loss of fluor of a tooth and compare this effect caused by two different kinds of soft drinks. Methodology: 30 bicuspids were put in two different groups, 15 in each, extracted by ortodontics indication The tooth did not have evidence of clinical pathology. The experiment consisted in applying an ionic buffer, and later put the results in a calibration curve. So with a p

  11. Uso estructural de vigas DÚO y TRÍO. Vigas de madera compuestas por dos o tres piezas: una alternativa ideal para estructuras ligeras de alta exigencia estética

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    García Barbero, Manuel

    2007-06-01

    ía más complejo, dado que los técnicos y profesionales del sector se han de someter a normas cada vez más exigentes que pretenden garantizar la calidad final de la edificación. Paralelamente a lo mencionado existe otra evolución que repercute en todo el espectro de materiales y sistemas constructivos, también en la madera. Convertir la madera en un material con características estandarizadas es una tarea compleja pero llena de soluciones inteligentes. El concepto DÚO y TRÍO es una muestra más de ingeniería de materiales que surge de la adecuada realización de análisis de las características propias del material y una aplicación técnica consecuente de los conocimientos del mismo para generar un nuevo producto industrial de alto valor añadido.Este concepto concreto consiste en la unión, por medio de encolado, de piezas de madera de formatos superiores a las láminas corrientes de vigas laminadas. Esta unión se realiza de forma tal que dichas piezas queden con la superficie de encolado en posición vertical, de tal modo que las caras con los anillos de crecimiento más exteriores queden en el interior de la viga y las caras que se situaban más interiormente en el tronco original, queden vistas hacia fuera. Las ventajas son múltiples: desde el punto de vista visual los cortes más interiores presentan menos nudos y son éstos los que aparecen en la cara exterior en el sistema DÚO. Desde el punto de vista de la geometría de las vigas, las deformaciones de las mismas son menores y el fendado lateral casi inexistente. Desde el punto de vista de las propiedades mecánicas, se consigue una optimización en el uso de la madera de costeros del tronco originario, de una mayor resistencia, uniéndose para conformar piezas de mayor escuadría.

  12. Consideraciones teórico prácticas acerca de la soldadura de los aceros al carbono

    Directory of Open Access Journals (Sweden)

    Osmundo Héctor Rodríguez Pérez

    2006-01-01

    Full Text Available Se analizan los tres tipos de aceros al carbono y su clasificación desde el punto de vista de su soldabilidad. Se pueden observar los aspectos físico - químicos en la zona fundida, zona de transición y zona afectada por el calor. Existen varios aspectos en la tecnología de la soldadura de los aceros al carbono, tales como: preparación de los bordes, limpieza superficial, posición relativa de las piezas, precalentamiento, selección del material de aporte, deposición de los cordones, postcalentamiento, tratamiento térmico posterior y el control de la calidad de las uniones soldadas a tomar en cuenta para realizar la soldadura.

  13. Microstructural effects of phosphorus on pressure die cast Al-12Si components

    Directory of Open Access Journals (Sweden)

    Suárez-Peña, B.

    2007-10-01

    Full Text Available The refinement of cuboidal silicon in eutectic Al-Si alloys by phosphorus additions used to manufacture pressure die cast components was studied. The results show that the addition of phosphorus in the form of AlFeP mother alloy before process degassing, leads to the best refinement of the size of the Si-cuboids phase, among several phosphorus additions analysed in the present research.

    Se ha estudiado el afino del silicio cuboidal en aleaciones eutécticas Al-Si por acción del fósforo, en piezas obtenidas mediante la técnica de fundición a presión. Tras la adición de fósforo en pruebas industriales, en las que dicho elemento se incorpora al baño con diversas composiciones, los mejores resultados se obtienen con la adición de la aleación madre AlFeP, previa al desgasificado industrial.

  14. "Estudio tribologico de aceros para moldes. Aplicacion al moldeo por inyeccion de polibutilentereftalato reforzado con fibra de vidrio"

    Science.gov (United States)

    Martinez Mateo, Isidoro Jose

    fabricacion del molde, tienen una gran influencia sobre su comportamiento en servicio a lo largo de la vida util del molde. En la primera parte del presente estudio, a partir de ensayos punzon sobre disco, se ha determinado la relacion entre la resistencia al desgaste y la dureza de aceros para moldes obtenidos a partir de bloques de gran espesor, estudiando los principales mecanismos de desgaste que tienen lugar. A continuacion, con el fin de determinar el dano superficial que sufren los aceros para moldes en condiciones reales de inyeccion, se han estudiado distintos tipos de aceros utilizados comercialmente en moldes de inyeccion de polimeros y materiales compuestos, seleccionando las condiciones de operacion para determinar la variacion de la rugosidad superficial del acero en funcion del material inyectado, del numero de operaciones sucesivas de inyeccion y de la orientacion del flujo de inyeccion, mediante tecnicas de perfilometria optica y microscopia electronica de barrido. Ademas del dano superficial sufrido por el acero con el numero de piezas inyectadas, tambien se ha determinado la evolucion de la rugosidad superficial de los materiales inyectados, polibutilentereftalato (PBT) puro y materiales compuestos derivados de PBT por adicion de un 20 o un 50% en peso de fibra de vidrio. En el caso de las piezas inyectadas, se ha caracterizado su microestructura en funcion del flujo de inyeccion y de la densidad de fibra, se han determinado sus propiedades termicas y dinamico-mecanicas, asi como la variacion de la rugosidad superficial de las piezas inyectadas con el numero de operaciones de inyeccion y con la geometria de las distintas secciones de las piezas. Finalmente, se ha evaluado la resistencia a la abrasion de PBT reforzado con un 50% de fibra, en funcion del numero de piezas inyectadas y de la direccion de rayado con respecto a la orientacion del flujo de inyeccion.

  15. El Atlas Anatómico de la Facultad de Medicina de la Universidad de Zaragoza. La recuperación de una pieza importante del patrimonio histórico universitario.

    Directory of Open Access Journals (Sweden)

    Moralejo Álvarez, María Remedios

    2012-01-01

    Full Text Available La Universidad de Zaragoza puede honrarse de poseer dos piezas excepcionales, fruto del genio de los dos aragoneses más universales: un ejemplar de la primera edición de los Caprichos de Goya con comentarios manuscritos y el Atlas de Anatomía de Cajal y sus sucesores. Este artículo informa sobre el tratamiento de estas dos obras en la Biblioteca Universitaria y se centra en el Atlas de Anatomía, restaurado. El Atlas es un enorme volumen (1.385 x 950 x 9.5 cm y unos 60 Kg de peso con tapas de madera forradas de arpillera, lomos y cantoneras de piel y dos cierres metálicos, con 34 hojas que contienen 49 láminas en color, las doce primeras tradicionalmente atribuidas a Cajal entre 1877 y 1883 y las restantes de otros autores, contemporáneos o posteriores. El Atlas fue, durante años, intensamente utilizado en las clases como material didáctico. Cuando dejó de utilizarse, a los daños producidos por el uso se sumaron los de la humedad. El Atlas de Anatomía, restaurado, y enriquecido con seis láminas descubiertas en el proceso de restauración, se incorporó a la colección histórica de la biblioteca Universitaria.The University of Zaragoza can be honoured of owning two exceptional pieces, fruit of the genius of the two most universal Aragonese men: a copy of the first edition of Goya's Caprichos with manuscript commentaries, and the Atlas of Anatomy of Cajal and his successors. This article reports on dealing with both works in University Library and focuses on the Atlas of Anatomy restored. The Atlas is an enormous volume (1.385 x 950 x 9.5 cm. and nearly 60 kg in weight with wooden covers lined with burlap, leather spine and cornerpieces and two metal clasps, with 34 leaves containing 49 pictures in colour, the first twelve are traditionally attributed to Cajal, betwen1877 and 1883; the following pictures from other authors, contemporary and later than Cajal. The Atlas was intensively used in the classroom for many years as didactic

  16. Mouthparts and associated sensilla of a South American moth, Synempora andesae (Lepidoptera: Neopseustidae Piezas bucales y sensilios asociados de Synempora andesae, una polilla de Sudamérica (Lepidoptera: Neopseustidae

    Directory of Open Access Journals (Sweden)

    Michel J. Faucheux

    2008-06-01

    Full Text Available The mouthparts of Synempora andesae Davis & Nielsen were studied by means of scanning electron microscope. The existence of gustative uniporous sensilla styloconica is demonstrated for the second time on the proboscis of Neopseustidae. It is with this family, and not at a later stage within the Incurvaroidea, that these sensilla appear during the evolution of Lepidoptera. Contrary to common belief, the labial-palp-pit organ, or organ of vom Rath, is present at the distal extremity of the labial palpi of S. andesae. It is made up of a dozen of grooved multiporous sensilla coeloconica whose function is carbon dioxide sensitive. Thus, its presumed absence can no longer be considered as an autapomorphy of Neopseustidae. S. andesae possesses other original characteristics: both short and long bifurcate aporous sensilla chaetica on the labrum, numerous sensilla campaniformia on the first segment of labial palpi, as well as those previously described: the double-tube configuration of the proboscis and the composite and polymorphic multiporous sensilla basiconica on the antennae. Other cephalic sensilla are also described: aporous bifurcate sensilla chaetica on the clypeus, aporous sensilla campaniformia above the mandibles, and on the chaetosemata.Las piezas bucales de Synempora andesae Davis & Nielsen fueron estudiadas con un microscopio electrónico de barrido. Se demuestra, por segunda vez, la existencia de sensilios estilocónicos gustativos uniporosos en la proboscis de Neopseustidae. Es en esta familia, y no en un estadio posterior dentro de Incurvaroidea, que aparecen estos sensilios durante la evolución de Lepidoptera. Contrario a lo que se cree, el órgano sensitivo labial u órgano de Von Rath, se encuentra en la extremidad distal del palpo labial de S. andesae. Está conformado por una docena de sensilios celocónicos multiporosos estriados, cuya función es percibir el dióxido de carbono. Por lo tanto, su supuesta ausencia ya no puede

  17. Microestructura y propiedades mecánicas de una fundición esferoidal ferrítica en bruto de colada para su uso en piezas de grandes dimensiones

    Directory of Open Access Journals (Sweden)

    Suárez-Sanabria, A.

    2006-02-01

    Full Text Available In order to carry out a study of the effect of the cooling rate, the composition and the microstructure upon the mechanical properties of a cast iron with nodular graphite and ferrite matrix for heavy sections, one cube with an edge of 300 mm was manufactured through casting in sand molds. This cube contains, as it is habitual, silicon and magnesium which proceed from the inoculant (ferrosilicon and from the nodulizant (Fe-Si-Mg. The effects of the size, shape and distribution of the graphite nodules and of the microstructure of the matrix upon the mechanical resistance, impact behaviour and fracture toughness of this cast iron are investigated in two zones of the cube which have been casted with a different cooling rate: the thermal centre and the surface. The chemical compositions and the techniques used to perform the mechanical tests and the metallographic analysis are suplied.

    Con objeto de estudiar el efecto de la velocidad de enfriamiento, composición y microestructura sobre las propiedades mecánicas de una fundición de grafito esferoidal y matriz ferrítica en estado de bruto de colada, para su uso en piezas de grandes dimensiones, se fabricó un cubo de 300 mm de arista mediante colada en moldes de arena. Este cubo contiene, como es habitual, silicio y magnesio procedentes del inoculante (ferrosilicio y del nodulizante (Fe-Si-Mg. Se investigaron los efectos del tamaño, forma y distribución de las partículas de grafito y microestructura de la matriz sobre la resistencia mecánica, resistencia a impacto y tenacidad de fractura, de dos zonas del cubo formadas con distinta velocidad de enfriamiento: el centro térmico-geométrico y la superficie. Se ofrecen las composiciones químicas de ambas zonas y las técnicas utilizadas para realizar los ensayos mecánicos y el análisis metalográfico.

  18. Algunas piezas olmecas de Chiapas y Guatemala

    OpenAIRE

    Navarrete, Carlos

    2010-01-01

    En este artículo se hace la descripción de algunas esculturas provenientes de Chiapas y Guatemala, con la intención de conocer algunos datos que permitan entender la dispersión de la cultura olmeca en Mesoamérica. Las esculturas que se describen presentan elementos artístico-simbolicos y la mayoría de ellas tienen la forma de serpiente. 

  19. AL Amyloidosis

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    Desport Estelle

    2012-08-01

    Full Text Available Abstract Definition of the disease AL amyloidosis results from extra-cellular deposition of fibril-forming monoclonal immunoglobulin (Ig light chains (LC (most commonly of lambda isotype usually secreted by a small plasma cell clone. Most patients have evidence of isolated monoclonal gammopathy or smoldering myeloma, and the occurrence of AL amyloidosis in patients with symptomatic multiple myeloma or other B-cell lymphoproliferative disorders is unusual. The key event in the development of AL amyloidosis is the change in the secondary or tertiary structure of an abnormal monoclonal LC, which results in instable conformation. This conformational change is responsible for abnormal folding of the LC, rich in β leaves, which assemble into monomers that stack together to form amyloid fibrils. Epidemiology AL amyloidosis is the most common type of systemic amyloidois in developed countries with an estimated incidence of 9 cases/million inhabitant/year. The average age of diagnosed patients is 65 years and less than 10% of patients are under 50. Clinical description The clinical presentation is protean, because of the wide number of tissues or organs that may be affected. The most common presenting symptoms are asthenia and dyspnoea, which are poorly specific and may account for delayed diagnosis. Renal manifestations are the most frequent, affecting two thirds of patients at presentation. They are characterized by heavy proteinuria, with nephrotic syndrome and impaired renal function in half of the patients. Heart involvement, which is present at diagnosis in more than 50% of patients, leading to restrictive cardiopathy, is the most serious complication and engages prognosis. Diagnostic methods The diagnosis relies on pathological examination of an involved site showing Congo red-positive amyloid deposits, with typical apple-green birefringence under polarized light, that stain positive with an anti-LC antibody by immunohistochemistry and

  20. Innovación y ruptura en la métrica de la poesía en al-Maqāmāt al-Luzūmiyya de al-Saraqusṭī (s. VI/XII

    Directory of Open Access Journals (Sweden)

    Ferrando, Ignacio

    2016-06-01

    Full Text Available Al-Maqāmāt al-Luzūmiyya, a collection of 50 picaresque-like stories couched in rhymed prose by Abū l-Ṭāhir al-Saraqusṭī in al-Andalus in the VI/XIIth century, were considered by Western scholars, up until the eighties of XXth century, as highly rhetorical pieces with a negligible and irrelevant content. However, some contemporary scholars argued that they contain some degree of social and political criticism, as they constitute a fictional domain in which subversion and irony play a fundamental role. In this paper, we cast some light on the particular use of metrical patterns in Al-Maqāmāt al-Luzūmiyya, which should be considered another subversion field: a poetical rhythm that avoids the most usual Arabic metrical patterns, contributing to provide the maqāma a flavor of the countergenre.Al-Maqāmāt al-Luzūmiyya, la colección de 50 relatos de corte picaresco escritos en una exigente prosa rimada por Abū l-Ṭāhir al-Saraqusṭī en al-Andalus en el siglo VI/XII, han sido consideradas por los críticos occidentales como piezas de alta retórica y de virtuosismo lingüístico en las que el contenido es prácticamente irrelevante. Sin embargo, a partir de los años 80 del siglo pasado, algunos investigadores han tratado de incidir en el hecho de que esta obra contiene cierto grado de crítica social y política, puesto que constituye un espacio ficticio en el que la subversión y la ironía desempeñan un papel fundamental. En este trabajo vamos a tratar de arrojar luz sobre el uso particular de los esquemas métricos por parte de al-Saraqusṭī, tratando de mostrar que los metros constituyen otro más de los ámbitos de subversión tan caros al autor. De hecho, el uso de ritmos “invertidos” o contrarios a los más habituales de la poesía clásica contribuye a darle a la maqāma ese aire de anti género que la puebla.

  1. Botella al mar para el dios de las palabras. Reflexiones de García Márquez sobre gramática y ortografía

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    Mar Jiménez Mañas

    2012-12-01

    Full Text Available La apertura del Congreso Internacional de la Lengua Española de Zacatecas, que estuvo a cargo de Gabriel García Márquez bajo el título “Botella al mar para el dios de las palabras” evidenció que no todos los hispanistas tienen una visión uniforme sobre la situación actual del español, su ortografía y su gramática. El escritor refleja una corriente de opinión sobre simplificación ortográfica y gramaticaliniciada varios siglos antes (desde Nebrija, Correas, Bello y más adelante con las propuestas de Juan Ramón Jiménez que tiene en esta ocasión una contestación contundente por parte de otros intelectuales hispanoparlantes. En el presente artículo analizamos la polémica aportando los puntos de vista más relevantes sobre la cuestión para concluir que una ortografía fonémica como la nuestra sólo se sustenta con el pilar de una ortografía históricamente coherente.

  2. Los maestros: piezas clave en la detección, identificación y atención de los niños con altas capacidades en Educación Primaria

    OpenAIRE

    Gutiérrez-Grau, María Ángeles

    2013-01-01

    El tema de las altas capacidades está teniendo, desde hace algún tiempo, una gran repercusión social. En la mayoría de ocasiones, al referirnos a un niño superdotado se tiene la imagen de un niño extraño y sabelotodo. Esto no deja de ser un estereotipo. Tras una amplia revisión bibliográfica, en el presente trabajo se acerca al lector a los términos, características, necesidades y respuestas educativas de los niños más dotados. En una primera parte se describe el concepto de necesidades educa...

  3. Valor pronóstico de la expresión de las metaloproteinasas y de sus inhibidores tisulares en células inflamatorias del estroma peritumoral estudiada mediante micromatices tisulares en piezas de prostatectomía radical

    OpenAIRE

    Rodríguez Corcos, Ángel

    2015-01-01

    Introducción: Hay nuevas evidencias que la inflamación prostática puede contribuir al carcinoma de próstata. La gran mayoría de las muestras quirúrgicas de tejido prostático muestran alguna evidencia de inflamación prostática. La identificación de un fenotipo de células mononucleares inflamatorias asociadas con el riesgo de cáncer de próstata y/o comportamiento agresivo del tumor puede ser de un gran interés, nos permitiría identificar a hombres en riesgo de desarrollar cáncer de próstata que...

  4. Amyotrophic Lateral Sclerosis (ALS)

    Science.gov (United States)

    ... benefit of 16 months before onset of severe respiratory failure. Other treatments are designed to relieve symptoms and ... of ALS. Most people with ALS die from respiratory failure, usually within 3 to 5 years from the ...

  5. Volver al desarrollo

    Directory of Open Access Journals (Sweden)

    Jaime Ornelas Delgado

    2012-01-01

    Full Text Available El desarrollo, categoría empleada para expresar el crecimiento económico, surge durante la "guerra fría" y si bien fue propuesta por teóricos metropolitanos, se asumió en Latinoamérica como parte de los instrumentos disponibles para lograr el crecimiento y alternativa al socialismo. El desarrollo mantuvo su vigencia entre 1945 y 1975, cuando al advenimiento del neoliberalismo fue paulatinamente retirado de la agenda de las preocupaciones nacionales e internacionales. Al iniciarse el siglo xxi, el fracaso del mercado autorregulado trajo de nueva cuenta al debate los problemas del desarrollo, lo que obliga a revisarlo críticamente, tanto como al concepto mismo para mostrar su carácter colonial, si se quiere construir caminos ajenos al neoliberal y superar los problemas que han hecho de Latinoamérica una de las regiones más desiguales del mundo.

  6. Jalta als Heterotopie

    OpenAIRE

    Schmid, Ulrich

    2013-01-01

    Jalta ist ein Ort, der sich im europäischen Kulturgedächtnis sowohl historisch als auch literarisch als "radikal anderer Ort" - als " Heterotopie" - festgesetzt hat. An der Konferenz von Jalta wurde 1945 eine neue Weltordnung geschaffen in der Hoffnung auf eine bessere Welt. Auch in den Werken von Anton ?echov, vor allem in denjenigen, die in Jalta entstanden sind, wird von einer anderen und besseren Welt geträumt.

  7. Pornographie als Metapher

    OpenAIRE

    Caroline Schubarth

    2010-01-01

    In diesem Artikel werden unterschiedliche metaphorische Verwendungen des Pornografiebegriffs und deren Implikationen untersucht. Während die Existenz von Pornografie der feministischen Anti-Porno-Bewegung als Erklärung für die anhaltende Diskriminierung von Frauen in westlichen Gesellschaften dient, nutzen rechtskonservative Kräfte den Pornografievorwurf als Rechtfertigung für die Zensur von als deviant empfundenen Identitäten und sexuellen Praktiken.This article...

  8. Pornographie als Metapher

    Directory of Open Access Journals (Sweden)

    Caroline Schubarth

    2010-02-01

    Full Text Available In diesem Artikel werden unterschiedliche metaphorische Verwendungen des Pornografiebegriffs und deren Implikationen untersucht. Während die Existenz von Pornografie der feministischen Anti-Porno-Bewegung als Erklärung für die anhaltende Diskriminierung von Frauen in westlichen Gesellschaften dient, nutzen rechtskonservative Kräfte den Pornografievorwurf als Rechtfertigung für die Zensur von als deviant empfundenen Identitäten und sexuellen Praktiken.

  9. Gezondheid als marketinginstrument

    NARCIS (Netherlands)

    Vijver, van de L.P.L.; Berg, van den I.

    2008-01-01

    Is biologisch voedsel beter dan gangbaar? Hoe hard zijn de bewijzen daarvoor? En hoe sterk moet het bewijs zijn voordat je het als claim op een product mag zetten? In dit Biokennis bericht een overzicht van de wetenschappelijke conclusies en de mogelijkheden om biologisch te promoten als beter, neer

  10. Al-Anon/Alateen

    Science.gov (United States)

    Find an Al-Anon meeting Español | Français 2018 Int'l Convention Home About Group Meetings What If I'm not ready ... a meeting? What can I expect at an Al-Anon meeting? What was my first meeting like? ...

  11. Al - BASED CAST COMPOSITES

    Directory of Open Access Journals (Sweden)

    Rakesh Kumar Yadav

    2011-08-01

    Full Text Available The economy is very important feature nowadays in themarket. The researches are playing an important role inengineering field to increase the life of machine parts /components and decrease the cost. The compositematerials have the potential to replace widely used steeland aluminium due to their good characteristics withbetter performance. The Al-based composites have foundextensive applications in automobile industries andaerospace industries due to their increased stiffness,strength, thermal conductivity and wear resistanceproperties. A number of particulate phases have beenemployed in the Al-alloy matrix. The cast aluminiumceramicparticulate composites are finding applications inpistons, connecting rods, cylinder liner, engine cylinderblock, electrical contacts etc.The present investigation isbased on study of the effect of particulate phase on theSEM study, micro-hardness, elastic modulus, tensilestrength and the wear behaviour of Al-5 % SiC-7 % Fe,Al-10 % SiC-6 % Fe and Al-15 % SiC-5 % Fe composites.

  12. Realidad, sueño y utopía en La isla desierta. Un acercamiento al mundo teatral de Roberto Arlt

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    Camacho Delgado, José Manuel

    2001-12-01

    Full Text Available En la obra literaria del escritor argentino Roberto Arlt, la imaginación no conduce a los personajes a la liberación, sino a la derrota definitiva. Su teatro está lleno de criaturas miserables que tratan de sobreponerse inútilmente a los continuos encontronazos con la vida cotidiana. Sus obras contemplan numerosos desdoblamientos imaginativos que permiten al autor introducir diferentes niveles en la ficción y plantear el teatro dentro del teatro. En La isla desierta, una de sus piezas más breves y representadas, los personajes de una triste oficina portuaria experimentan un cambio radical en sus vidas cuando dejan de trabajar en un sótano y son trasladados a la décima planta de un inmueble. Allí, a través de un inmenso ventanal, son reclamados por un sinfín de tentaciones que se encuentran más allá del mundo gris de la oficina. Los empleados descubren los beneficios de la luz natural, la llegada de los buques, el bullicio de la calle, los reclamos de la libertad, elementos que acaban desestabilizando la rutina administrativa. No obstante, es el relato de uno de los personajes, el mulato Cipriano, cuya memoria es esencialmente literaria, el que arrastra al resto de los oficinistas a la ensoñación y a la consiguiente derrota.

  13. Un puñal-reliquia vacceo hallado en Pintia (Padilla de Duero, Valladolid

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    Sanz Mínguez, Carlos

    2008-12-01

    Full Text Available During excavation, the splendid scabbard of a Monte Bernorio dagger, made of iron and decorated with silver, was found carefully placed near the base of a clay seat inside a house in the city of Las Quintanas, in Pintia. Although the typological characteristics of the dagger date it to the 4th Century B.C., the dating of the house to the 1st Century A.D. suggests we are in the presence of a true relic, inherited through generations until its definitive interment at a time when the Vaccaean culture was undergoing a process of ‘dilution,’ being integrated in the effective Romanization of the area of the River Duero basin.

    Una espléndida vaina de hierro damasquinada en plata, correspondiente al modelo de puñal Monte Bernorio, cuyas características tipológicas remontan la pieza al siglo IV a.C., apareció, en proceso de excavación, cuidadosamente depositada junto a la base del banco de tapial de una vivienda de la ciudad de Las Quintanas, de Pintia. La casa se data, sin embargo en el siglo I d.C. En consecuencia, nos hallamos ante una verdadera reliquia que pasó de mano en mano a lo largo de generaciones, hasta su definitiva amortización en un momento en el que la cultura vaccea se diluía o, si se prefiere, se integraba en la romanización efectiva de este territorio central de la Cuenca del Duero.

  14. IFIC expone grandes piezas del acelerador particulas de Ginebra

    CERN Multimedia

    2005-01-01

    The Institute for corpuscular physics of Valencia University exhibits from today great pieces coming from the particle accelerator of CERN in Geneva, an underground laboratory of high technologic level producing small atomic particles which it makes collide at very high energies to study the fundamental components of the matter and its interactions (1 page)

  15. Contribuciones al desarrollo de la investigación en enfermería: retos y perspectivas

    Directory of Open Access Journals (Sweden)

    Myriam Durán Parra

    2012-12-01

    Full Text Available Desde la etimología del término “investigación” la palabra proviene del latín in (en y vestigare (hallar, inquirir, indagar, seguir vestigios. De ahí el uso más elemental del término en el sentido de “averiguar o describir alguna cosa”. Desde el momento en que el hombre se enfrentó a problemas y frente a ellos empezó a interrogarse sobre el porqué, como y para que, con esta indagación sobre las cosas, de una manera embrionaria, comenzó lo que hoy llamamos investigación. Con el transcurso del tiempo el ser humano ha hecho un esfuerzo importante por sobrevivir y la mejor forma de lograrlo ha sido experimentando aportando al desarrollo del conocimiento científico.Donaldson y Bottorff (1978 expresan frente a la investigación en enfermería que “es la fuente de desarrollo de conocimiento que le da la característica de disciplina, que ha de estar presente tanto en la práctica clínica como en el desarrollo de la administración y la educación, que ha de dar respuesta a las necesidades sociales que están relacionadas con procesos de salud-enfermedad, condiciones y calidad de vida de las personas, familias y comunidades, en todos los grupos etarios” (1. Por su parte Borrero-Cabal (1994, afirma que “la disciplina conlleva al sentido de rigor, de dedicación, de entrenamiento y ejercicio de los hábitos científicos de la persona para elaborar, transmitir y aprender una ciencia” (2. En enfermería esto se traduce que para poder llevar el cuidado a los pacientes de una manera técnica, científica , analítica, debe tener unas bases como la dedicación, el amor por la profesión y el gusto por la investigación reconociendo que la enfermería avanza y se fortalece a medida que crece científicamente, mientras conoce la cultura, la riqueza de la naturaleza, forma parte del país y sobre todo del mundo como una profesión que demuestra su interés en la búsqueda de su propia identidad. 

  16. Evaluación de la tasa de consumo de oxígeno de Colossoma macropomum en relación al peso corporal y temperatura del agua

    Directory of Open Access Journals (Sweden)

    Dennis Tomalá

    2014-11-01

    Full Text Available Colossoma macropomum es una especie de la región amazónica perteneciente a la familia Characidae, la de mayor diversidad de peces de agua dulce. A nivel de laboratorio, se determinó la tasa de consumo de oxígeno (CO en metabolismo de rutina de C. macropomum a diferentes pesos corporales: 40, 60, 90, 140 y 250 g (expresados por unidad de masa corporal y temperatura del agua de 21, 26 y 31°C. El experimento se diseñó completamente al azar en arreglo factorial (5x3x3, utilizando un respirómetro de 20 L y una bomba de recirculación de agua. Las mediciones del CO fueron realizadas cada 5 min mediante el uso de un oxímetro digital. Los resultados indican que el CO mantiene relación directa con la temperatura del agua e inversa con el peso corporal de los organismos (P < 0,05. Las regresiones entre las variables independientes y el CO se ajustaron a ecuaciones potenciales: CO = 2844,9 P-0,734, CO = 2555,9 P-0,624 y CO = 1945,4 P-0,507 a 21, 26 y 31°C respectivamente; donde P se expresa en kg, obteniéndose altos coeficientes de correlación y determinación. La ecuación resultante del análisis multivariado de regresión lineal múltiple fue: CO = 4,839 - (0,708* P + (9,106* T. Los resultados ofrecen información para estimar la capacidad de un ambiente acuícola en base a la demanda de oxígeno de C. macropomum, aportando al desarrollo de una acuicultura con mayor sustento técnico.

  17. Sociale media als leermiddel

    NARCIS (Netherlands)

    Rubens, Wilfred

    2012-01-01

    Rubens, W. (2012, 5 juni). Sociale media als leermiddel. Presentatie over het gebruik van sociale media binnen het onderwijs, verzorgd tijdens een ouderraadbijeenkomst van de Katholieke Scholengemeenschap Etten-Leur, Etten-Leur, Nederland.

  18. MDA ALS Caregiver's Guide

    Science.gov (United States)

    ... R.D., C.N.S.D., L.D.N. Nutritionist MDA/ALS Center at Vanderbilt University Medical Center ... neurologists, physiatrists, therapists (physical, occupa- tional, speech, respiratory), nutritionists, social work- ers, pulmonologists, gastroenterologists and medical equipment ...

  19. Regionale Herkunft als Bonus

    OpenAIRE

    Kratochvil, Dr. Ruth

    2004-01-01

    Der Bio-Sektor durchlebt bewegte Zeiten. Die biologische Landwirtschaft hat sich aus der Nische herausbewegt und dafür an „Besonderheiten“ eingebüßt. Diese müssen als Zusatznutzen wiedergefunden werden.

  20. Partizipation als Ausnahmezustand

    OpenAIRE

    Korf, Benedikt

    2009-01-01

    In «Die Erfindung des Politischen» (1993) beschreibt Ulrich Beck Subpolitik als den Ort, an dem die Grenze zwischen Politik und Nichtpolitik verschwindet. Aus der zunehmenden Wirkkraft von Subpolitik erwächst die grundlegende Frage, mit welcher Legitimation diese Art von Subpolitik in die Sphäre der institutionalisierten Politik eindringt. Beck’s Subpolitik soll im Anschluss an theoretische Arbeiten von Chantal Mouffe und Giorgio Agamben als post-politische Aspiration bezeichnet werden, die e...

  1. Der Preis als Kaufbarriere?

    DEFF Research Database (Denmark)

    Mueller Loose, Simone

    2012-01-01

    Die Preispolitik hat eine herausragende Stellung im Marketing. Der Preis eines Produktes ist für Verbraucher ein direkter Kostenfaktor und für Unternehmen die Stellgröße im Mar-ketingmix, die den Umsatz am stärksten beeinflusst (vgl. Nieschlag et al. 2002). Wenn die Akzeptanz und der regelmäßige...... Verzehr gesunder Lebensmittel erhöht werden soll, ist es sowohl für die Verbraucherpolitik als auch für Lebensmittelproduzenten wichtig, den Ein-fluss des Preises auf die Kaufentscheidung zu verstehen. Aus Verbrauchersicht ist der Preis neben dem Geschmack die wichtigste Produkteigen-schaft beim Kauf von...... Lebensmitteln (vgl. Brunsø/Grunert 1998) und stellt eine Kaufbarrie-re für Lebensmittel mit gesundheitsfördernden Eigenschaften dar. Studien in den USA (vgl. Cassady et al. 2007), Frankreich (vgl. Drewnowski et al. 2004; Andrieu et al. 2005) und Deutschland (vgl. Karg et al. 2008) kommen übereinstimmend zu dem...

  2. Modification of residual stress in Al-[AlBO]w/Al compound plate

    Institute of Scientific and Technical Information of China (English)

    姜传海; 吴建生; 王德尊

    2001-01-01

    The application of compound parts of Al-[AlBO]w/Al not only reduces the cost of the parts but also improves its properties. However, there is a large thermal residual stress between Al and [AlBO]w/Al, and it is harmful for practical application. From the theoretical analyses and experimental results, it was found that by the compressive pre-plastic deformation perpendicular to the interface between Al and [AlBO]w/Al, the interlayer residual stress of compound parts can be reduced, while the mechanical properties of compound parts can be improved.

  3. Fortschritt als Fortschrittsdiskurs

    Directory of Open Access Journals (Sweden)

    Rainer Schmid-Zartner

    2014-12-01

    Full Text Available Zur Erzielung gesellschaftlichen Fortschritts in demokratisch verfassten Gesellschaften soll die Möglichkeit am Fortschrittsdiskurs teilnehmen zu können für alle Mitglieder der Gesellschaft als selbstverständliche Prämisse gelten. Fortschritt wird also als Bewusstseinsbildung dem Fortschritt selbst gegenüber und als Entscheidungs- und Handlungsfähigkeit auf individueller und gesellschaftlicher Ebene definiert. Dies setzt entsprechende Maßnahmen zur Befähigung dazu voraus, die alle Mitglieder der Gesellschaft erfassen. Dabei ist der Bildungsbereich angesprochen, insbesondere der Schulunterricht. Neben dem in der aktuellen blidungspolitischen Debatte forcierten Fokus auf den Aspekt der Kompetenzorientierung, der hier nicht infrage gestellt wird, ist als notwendige Ergänzung ein reflexionsorientierter Schulunterricht in allen Bildungsfächern einzufordern und umzusetzen. Im Weiteren beschreibt der Text den Weg von der Brauchbarkeit zur Bedeutsamkeit von schulischem Wissen durch Relevanzreflexionsprovokationen im Schulunterricht, um Sinn und Bedeutung der vermittelten Bildungsinhalte zu verhandeln. Am Beispiel von Mathematik als Bildungsfach wird der Inhalt von reflexionsorientertem Unterricht verdeutlicht. Darüber hinaus beschreibt der Text eine Reihe von konkreten Fallbeispielen aus der aktuell versuchsweise durchgeführten Unterrichtspraxis in Mathematik.

  4. Pornographie als Metapher

    Directory of Open Access Journals (Sweden)

    Caroline Schubarth

    2010-03-01

    Full Text Available In diesem Artikel werden unterschiedliche metaphorische Verwendungen des Pornografiebegriffs und deren Implikationen untersucht. Während die Existenz von Pornografie der feministischen Anti-Porno-Bewegung als Erklärung für die anhaltende Diskriminierung von Frauen in westlichen Gesellschaften dient, nutzen rechtskonservative Kräfte den Pornografievorwurf als Rechtfertigung für die Zensur von als deviant empfundenen Identitäten und sexuellen Praktiken.This article examines different metaphorical uses of the term pornography and the resulting implications. While the existence of pornography for the feminist anti-porno movement serves as factor in the continuing discrimination of women in western societies, conservative powers on the right use the allegation of pornography as a justification for censorship of those identities and sexual practices deemed deviant.

  5. Wikipedia als Referenzorgan

    OpenAIRE

    Voß, Jakob

    2006-01-01

    Wikipedia wird inzwischen von vielen Nutzern regelmäßig als Nachschlagewerk genutzt. Aufgrund des offenen Charakters der Online-Enzyklopädie, bei der sich jeder direkt beteiligen kann, ist jedoch zusätzliche Medienkompetenz notwendig, um die Qualität einzelner Wikipedia-Artikel einschätzen zu können. Im Vortrag sollen Methoden zur Beurteilung von Wikipedia-Artikeln dargestellt und die Frage beleuchtet werden, unter welchen Umständen Wikipedia als Referenzorgan geeignet ist.

  6. Carta al Editor

    Directory of Open Access Journals (Sweden)

    José Andrés Burgos Zuleta

    2010-06-01

    Full Text Available La medicina al basarse generalmente en la clínica, correlacionaexámenes complementarios y organiza un diagnóstico y tratamiento, es una disciplina donde es imprescindible saber recolectar, analizar, interpretar y concretar una respuesta adecuada, es así que la información que se recibe es esencial para el desempeño médico.La certeza es una realidad que se da en algunas situaciones y enotras las probabilidades establecen conclusiones. Lo normal muchas veces se define sobre la base de criterios estadísticos, basados en riesgos poblacionales que no necesariamente se aplican al caso boliviano.

  7. El Alcázar de Madrid. Del castillo Trastámara al palacio de los Austrias (Ss. XV-1543

    Directory of Open Access Journals (Sweden)

    Alonso Ruiz, Begoña

    2014-12-01

    Full Text Available The medieval Alcázar (fortress of Madrid was transformed into the residential palace of the Austrian dynasty in Spain from the reign of Charles I through that of Charles II. On Christmas Eve 1734, during the reign of the Bourbon king Philip V, the palace suffered a devastating fire, resulting in the construction of a new Royal palace, already baroque, on the same site. This research reconstructs the history – until now fragmented – of this lost medieval castle, contributing new source materials concerning the successive interventions carried out on the building. Specifically, this investigation focuses on the improvements realized during the period of the Catholic Monarchs and the first works commissioned by Charles V, prior to the definitive royal bond of 1536. This document marks the beginning of a new chapter in the constructive history of the building, when the old castle was transformed definitively into a residential palace, while highlighting the symbolic value of the Sala Rica and the rooms of protocol constructed during the Trastámara period.El alcázar medieval de Madrid se convirtió en la gran residencia de los Austrias desde la llegada de Carlos I al reinado de Carlos II. En la Nochebuena de 1734, reinando ya Felipe V de Borbón, el palacio sufrió un devastador incendio, resultado del cual se inicia la construcción del nuevo Palacio Real, ya barroco, sobre su solar. En esta investigación nos ocupamos de reconstruir la historia –hasta ahora fragmentada– de ese castillo medieval, aportando nuevos datos documentales acerca de las sucesivas intervenciones sufridas en el edificio. Nos centramos de forma especial en las obras realizadas en el período de los Reyes Católicos y en las primeras encargadas por Carlos V, antes de la definitiva real cédula de 1536 que marca el comienzo de un nuevo capítulo en la historia constructiva del edificio al transformarse de manera definitiva el viejo castillo en un palacio residencial

  8. Calculation of interaction of AlCl, AlCl2 and AlCl3 on Al4C3 (001) Al4CO4 (001) and Al2CO (001) planes

    Institute of Scientific and Technical Information of China (English)

    段少飞; 陈秀敏; 杨斌; 郁青春; 徐宝强; 刘大春

    2015-01-01

    To make sure the intermediate products of the carbothermic reduction of Al2O3 process, such as Al4CO4, Al2CO and Al4C3, and the interaction of AlCl, AlCl2, AlCl3 with Al4CO4, Al2CO and Al4C3, respectively, thermodynamic analyses were used to study the chloride reaction production of them under the vacuum situation. The stable structures and electronic properties of AlCl, AlCl2 and AlCl3 adsorbed on Al4CO4, Al2CO and Al4C3 were calculated by first-principles calculations by the CASTEP module in the Materials Studio program. The results show that the AlCl3 and AlCl2 molecules have decomposed on the plane of Al4C3 (001), while there are no obvious decomposition of AlCl3 and AlCl2 on Al4CO4 (001) and Al2CO (001) planes. The adsorption of AlCl on the Al4CO4 (001) and Al2CO (001) planes is stronger than that on the Al4C3(001) plane. The interaction strength of AlCl3, as well as AlCl2, with Al4CO4, Al2CO and Al4C3 is in the sequence of Al4CO4Al2CO>Al4C3.

  9. Comentarios al Salto Social

    Directory of Open Access Journals (Sweden)

    Facultad de Ciencias Económicas

    1995-06-01

    Full Text Available 1. El Plan considera que la política social es un componente central de la estrategia macroeconómica. A diferencia de la administración Gaviria, lo social ha dejado de ser un asunto marginal, es consustancial al desarrollo y, por tanto, se le confiere una dimensión cualitativamente diferente.

  10. Slowenisch als fremdsprache

    Directory of Open Access Journals (Sweden)

    Jože Toporišič

    1981-12-01

    Full Text Available Nicht ganz zwei Millionen Menschen sprechen Slowenisch als Muttersprache. Wenige gibt es, die das Slowenische zwar spre­ chen oder zu sprechen versuchen, aber eine andere Muttersprache haben, vielleicht hunderttausend; für die ist Slowenisch also eine Fremdsprache.

  11. ANÁLISIS DE OBRAS MUSICALES VENEZOLANAS Y EUROPEAS DE LOS SIGLOS XVIII, XIX Y XX REFERENTES AL REINO ANIMAL

    Directory of Open Access Journals (Sweden)

    Naudy Trujillo Muscia

    2012-09-01

    venezolanos y europeos de los siglos XVIII, XIX y XX. Los resultados indican a las aves silvestres como las más tratadas en piezas musicales tanto en Europa como en Venezuela; manifiestan también una proporción mayor de piezas musicales que tratan los animales de producción versus animales domésticos en Venezuela, mostrándose lo contrario en el continente europeo. Se concluye, en primer lugar, que tanto en Venezuela como en Europa, la cultura humana busca enaltecer la fauna silvestre, ya sea de forma naturalista o romántica; se confirma el fuerte arraigo de la mentalidad agropecuaria venezolana y su importancia en el desarrollo de la cultura nacional a la par que en Europa; los resultados reflejan el poco contacto con áreas verdes abiertas y sistemas de producción agropecuarios que poseían los compositores y público académico de la época. Esta investigación fomenta la interdisciplinariedad en la sociedad científica venezolana, haciendo aportes científicos al desarrollo de la cultura, además de servir a docentes, terapeutas musicales, historiadores y la sociedad en general en sus investigaciones y ocupaciones al generar nuevas preguntas en el campo científico de la psiquis humana dentro de la relación hombre/animal y brindar nuevos conocimientos a la ciencia histórica de la Medicina Veterinaria y la Música Universal.

  12. ALS insertion devices

    International Nuclear Information System (INIS)

    The Advanced Light Source (ALS), the first US third generation synchrotron radiation source, is currently under construction at the Lawrence Berkeley Laboratory. The low-emittance, 1.5 GeV electron storage ring and the insertion devices are specifically designed to produce high brightness beams in the UV to soft X-Ray range. The planned initial complement of insertion devices includes four 4.6 m long undulators, with period lengths of 3.9 cm, 5.0 cm (2) and 8.0 cm, and a 2.9 m long wiggler of 16 cm period length. Undulator design is well advanced and fabrication has begun on the 5.0 cm and 8.0 cm period length undulators. This paper discusses ALS insertion device requirements; general design philosophy; and design of the magnetic structure, support structure/drive systems, control system and vacuum system. 18 refs., 9 figs., 5 tabs

  13. De GPS al mapa

    Directory of Open Access Journals (Sweden)

    Esteban Dörries

    2016-03-01

    Full Text Available Las coordenadas Lambert obtenidas a partir de mediciones con equipos GPS de mano, llamados a veces navegadores, en ciertos casos confunden al usuario, por diferir claramente de su posición real al ser graficadas en un mapa del Instituto Geográfico Nacional (IGN: Esto puede resolverse con suficiente exactitud mediante una transformación de Molodensky, seguida de la correspondiente proyección cartográfica. Sin embargo, los tres parámetros necesarios para la transformación, supuestamente válidos para Costa Rica, se encuentran en muchas variantes y producen obviamente resultados diferentes. En este trabajo se analizan los fundamentos del problema y sus posibles soluciones, culminando con un estudio comparativo de ocho casos, que permite seleccionar los valores más adecuados para los parámetros.

  14. AL-IZDIWAJIYYAH AL-LUGHOWIYAH FII ISTIHDHAMI AL-LUGHOH AL-‘ARABIYAH

    OpenAIRE

    Imam Muslimin

    2011-01-01

    Al-Izdiwajiyyah (diglosia) is standardizing a specific language when there are two variants of language that live side by side in societal life and each variant has its own social function. Disglosia is related to the use of local languages variations of low language and high language in a community. In Arabic language, disglosia covers dialects among the speakers, for instance there are two variants of language that each has roles and functions. The use of the variant depends on the situatio...

  15. Carta al editor

    Directory of Open Access Journals (Sweden)

    Harry Pachajoa

    2012-02-01

    Full Text Available Recently, Valencia et al., published a very interesting article called «Lipid profile in a group of patients with Turner’s syndrome at Clínica Universitaria Bolivariana in the city of Medellín between 2000 and 2009". An article which evaluated lipid levels in patients withTurner syndrome in a Colombian clinic, the study associated results of lipid profile with karyotype and other risk factors for coronary heart disease.

  16. Carta al editor

    OpenAIRE

    Harry Pachajoa

    2012-01-01

    Recently, Valencia et al., published a very interesting article called «Lipid profile in a group of patients with Turner’s syndrome at Clínica Universitaria Bolivariana in the city of Medellín between 2000 and 2009". An article which evaluated lipid levels in patients withTurner syndrome in a Colombian clinic, the study associated results of lipid profile with karyotype and other risk factors for coronary heart disease.

  17. Modeling neuronal vulnerability in ALS.

    Science.gov (United States)

    Roselli, Francesco; Caroni, Pico

    2014-08-20

    Using computational models of motor neuron ion fluxes, firing properties, and energy requirements, Le Masson et al. (2014) reveal how local imbalances in energy homeostasis may self-amplify and contribute to neurodegeneration in ALS.

  18. AL-USRCRN Station Information

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Documentation of United States Alabama Regional Climate Reference Network (AL-USRCRN) installations in 2006. Installations documented are for AL-USRCRN pilot...

  19. ICT als medicijn tegen onveiligheid

    OpenAIRE

    Linders, Lilian; Steyaert, Jan

    2002-01-01

    Hoe verhoudt ICT zich tot veiligheid? SQM zou niet 'ict oplossingen voor sociale kwesties' als ondertitel hebben, als we geen aandacht gaven aan deze vraag. In de eerste Rode Draad Notitie verkent SQM dit thema.

  20. Formación de capa híbrida al cementar postes metálicos y de fibra de vidrio en dientes tratados endodónticamente Hybrid layer formation using metal post and fiber post into endodontically trated canal roots

    Directory of Open Access Journals (Sweden)

    V. Valenzuela Aránguiz

    2010-04-01

    Full Text Available Se evaluó al microscopio electrónico de barrido (MEB la efectividad de la adhesión lograda dentro de conductos tratados utilizando dos sistemas adhesivos, uno de fotocurado (Single Bond y otro dual (Prime & Bond NT + Self-Cure Activator y dos sistemas de postes (fibra de vidrio y metálicos. El objetivo fue evaluar la formación de capa híbrida y tags de resina al interior de los conductos radiculares. Método: Doce piezas dentarias fueron preparadas para recibir un poste. Se dividieron en dos grupos de 6 piezas, a cada uno de los cuales se les colocó un tipo de poste. Ambos grupos fueron subdivididos en dos, aplicándoles distintos adhesivos, la resina de cementación RelyX ARC y el poste correspondiente. Las muestras fueron cortadas longitudinalmente y preparadas para la observación al MEB. Resultados: No se evidenciaron diferencias en cuanto al espesor de la capa híbrida entre los grupos. Se concluye que la capa híbrida y tags de resina formados dentro de los conductos utilizando ambos sistemas de postes y diferentes sistemas adhesivos, no son satisfactorios.The goal of this study was to evaluate the adhesive effectiveness attained in root canals endodontically treated with a scanning electronic microscope (SEM. We used two adhesive systems (Single Bond and Prime&Bond NT + Self Cure Activator and two post systems (fiberglass and metallic. The main objective was to evaluate the hybrid layer and resin tag formation inside each root canal. Twelve teeth were used, which were prepared for receiving the post. The teeth were divided into two groups of 6 pieces each. Each group received one type of post. In turn, each group was subdivided in two (a total of 4, receiving different adhesives, the cementation resin RelyX ARC and the corresponding post. The samples were cut longitudinally and prepared to be scrutinized with the microscope. The results showed that the adhesion inside the canal roots was not reliable. No difference regarding the

  1. Gliricidia sepium al establecimiento

    Directory of Open Access Journals (Sweden)

    J. L. Valle

    2004-01-01

    Full Text Available Se asoció Cenchrus ciliaris (Cc y Gliricidia sepium (Gs para evaluar la producción de biomasa y la composición química de los forrajes en la fase de establecimiento, en el estado de Morelos, México, en condiciones de trópico seco. Se empleó un análisis de varianza con diseño en bloques al azar, en donde T1 fue pasto solo, T2 Cc más Gs con 5,000 plantas ha-1 y el T3 Cs más Gs con 14,285 plantas ha-1. Se midió la producción de forraje individual y asociado con materia seca (t MS/Ha, la altura (A en cm, la proteína cruda (PC%, las fracciones de fibra (FDN% y FDA% y la digestibilidad in vitro de la materia seca (DIVMS%. El T3 tuvo una mejor producción de biomasa (P0.05. La asociación de 14,285 plantas ha-1 de G. sepium con pasto Cenchrus ciliaris mejoró la producción de biomasa y la disponibilidad total de nutrientes por superficie cultivada al establecimiento

  2. Derivados vinculados al seguro.

    Directory of Open Access Journals (Sweden)

    De Paz Cobo, Sonia

    2003-01-01

    Full Text Available El presente trabajo tiene como objetivo la presentación de los derivados financieros como instrumentos de cobertura de los riesgos del seguro, así como de los principales proyectos que se desarrollan a través de los mismos, como por ejemplo los derivados sobre el clima. Hay que tener presente las pérdidas multimillonarias ocasionadas en casos como el de la banca Baring’s, o el de Orange County, por citar algunas, que si bien ciertos autores afirman que están en relación directa con el uso de estos productos, no podemos olvidar que los instrumentos derivados se desarrollaron con el objetivo principal de proteger al usuario de la posible volatilidad del activo subyacente. Ya en la industria aseguradora los derivados vinculados a tal actividad son instrumentos donde el pago se condiciona a la ocurrencia de su suceso de siniestro, o serie de sucesos múltiples que disparen las pérdidas. Tras el repaso efectuado y la descripción que este tipo de instrumentos puede tener en la gestión del riesgo por parte de la industria aseguradora, concluiremos con la exposición de las relaciones con el reaseguro tradicional así como una breve referencia al futuro de este tipo de instrumentos

  3. El comportamiento del consumidor financiero: enfoque transaccional vs. enfoque relacional

    OpenAIRE

    Navarro Sanz, Alfonso

    2012-01-01

    El objetivo central de la investigación es, por una parte, contrastar la existencia de dos modelos comportamentales contrapuestos en el sector financiero, profundizando en el estudio referente al impacto que puede tener dicho hecho en la gestión de los intercambios y las relaciones con los particulares, y aportando una visión teórica que respalde las primeras interpretaciones. Por otra parte, explorar sobre las variables explicativas de los distintos patrones comportamentales aportando ...

  4. Corrosion behaviour of Al/SiC and Al/Al2O3 nanocomposites

    Directory of Open Access Journals (Sweden)

    Tamer Samir Mahmoud

    2012-12-01

    Full Text Available In the present investigation, the static immersion corrosion behavior of Al/Al2O3 and Al/SiC nanocomposites in 1 M HCl acidic solution was evaluated. The nanocomposites were fabricated using conventional powder metallurgy (P/M route. The effect of nanoparticulates size and volume fraction on the corrosion behavior of nanocomposites was studied. The durations of the corrosion tests ranged from 24 to 120 hours and the temperatures of the solution ranged from ambient to 75 ºC. The corrosion rates of the nanocomposites were calculated using the weight loss method. The results showed that both Al/SiC and Al/Al2O3 MMNCs have lower corrosion rates than the pure Al matrix. Such behavior was noticed at both ambient and higher temperatures. Generally, the Al/Al2O3 nanocomposites exhibited lower corrosion rates than the Al/SiC nanocomposites. The Al/Al2O3 (60 nm nanocomposites exhibited the highest corrosion resistance among all the investigated nanocomposites. The corrosion rate was found to be reduced by increasing of the exposure time and the volume fraction of the nanoparticulates, while it was found to be increased by increasing of the nanoparticulates size and the solution temperature.

  5. Doppelthydrophile Blockcopolymere als Mineralisationstemplate

    Science.gov (United States)

    Kasparova, Pavla

    2002-07-01

    Die vorliegende Arbeit beschäftigt sich mit der Synthese und den Eigenschaften von doppelthydrophilen Blockcopolymeren und ihrer Anwendung in einem biomimetischen Mineralisationsprozeß von Calciumcarbonat und Bariumsulfat. Doppelthydrophile Blockcopolymere bestehen aus einem hydrophilen Block, der nicht mit Mineralien wechselwirkt und einem zweiten Polyelektrolyt-Block, der stark mit Mineraloberflächen wechselwirkt. Diese Blockcopolymere wurden durch ringöffnende Polymerisation von N-carboxyanhydriden (NCA's) und a-methoxy-ω-amino[poly(ethylene glycol)] PEG-NH2 als Initiator hergestellt. Die hergestellten Blockcopolymere wurden als effektive Wachstumsmodifikatoren für die Kristallisation von Calciumcarbonat und Bariumsulfat Mineralien eingesetzt. Die so erhaltenen Mineralpartikel (Kugeln, Hantel, eiförmige Partikel) wurden durch Lichtmikroskopie in Lösung, SEM und TEM charakterisiert. Röntgenweitwinkelstreuung (WAXS) wurde verwendet, um die Modifikation von Calciumcarbonat zu ermitteln und die Größe der Calciumcarbonat- und Bariumsulfat-Nanopartikel zu ermitteln. This work describes the synthesis and characterization of double hydrophilic block copolymers and their use in a biomimetic mineralization process of Calcium Carbonate and Barium Sulfate. Double hydrophilic block copolymers consist of a hydrophilic block that does not interact with minerals and another hydrophilic polyelectrolyte block that strongly interacts with mineral surfaces. These polymers were synthesised via ring opening polymerisation of N-carboxyanhydride (NCA), and the first hydrophilic block a-methoxy-ω-amino[poly(ethylene glycol)] PEG-NH2 was used as an initiator. The prepared block copolymers were used as effective crystal growth modifiers to control the crystallization of Calcium Carbonate and Barium Sulfate minerals. The resulting mineral particles (spheres, dumbbells, egg-like particles) were characterised by light microscopy in solution, by SEM, and by TEM. X-Ray scattering

  6. COMENTARIO AL CASO PINOCHET

    Directory of Open Access Journals (Sweden)

    Alberto Contreras Clunes

    2002-01-01

    Full Text Available El fallo en el caso Pinochet tiene distintas formas de ser analizado. De partida, desde un punto de vista político, también constitucional, del derecho penal. Sin embargo, nos abocaremos al estudio desde el punto de vista procesal, en especial a lo referido al Debido Proceso. Para ello se analizará los presupuestos, la solución dada por la Excma. Corte Suprema y las consecuencias del mismo. Además, se criticará la solución dada, desde la óptica de las garantías procesales del imputado, contenidas en el nuevo proceso penal y lo dispuesto en la Constitución y la Convención Americana de Derechos Humanos. Finalmente, se argumentará en favor de una interpretación finalista y armónica de la Constitución y los tratados internacionales de derechos humanos.The verdict of the Pinochet Case has different ways of being analyzed: from the political, the constitutional, and the penal law points of view. However, we will approach this study from the legal point of view, especially to that referred to as the Proper Process. To do this, the budgets, the solution given by the Most Excellent Supreme Court, and its consequences will be analyzed. Furthermore, the given solution will be criticized from the point of view of the legal guarantees of the accused contained in the new penal process and what is contained in the Constitution and in the American Convention of Human Rights. In conclusion, we will argue in favor of a final and harmonious interpretation of the Constitution and the international agreement of human rights.

  7. Epitaxial growth of Al/Al2O3 multilayer structures

    International Nuclear Information System (INIS)

    In order to obtain Al-Al2O3 quantum effect devices, it is necessary to deposit epitaxially Al on Al2O3 and Al2O3 on Al. We have already obtained an epitaxial Al/Al2O3/Al structures on Si(111). In this paper, we have deposit Al/Al2O3/Al structures on Si(111), and investigated the crystallinity by using RBS. (author)

  8. Effect of AlN Particulate Size on Superplasticity of AlNp/6061 Al Composites

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Superplastic tensile tests of AlNp/606l Al Composites, fabricated by powder metallurgy techniques, were performed at strain rates ranging from 10-1-10-3S-1 and at temperatures from 833 to 893 K. Hot rolling after extrusion was employed to obtain a fine grained structure before \\superplastic testing. The superplastic behavior of AlNp/6061 Al Composites was compared with that of AlN particulate size. Differential scanning calorimeter was used to ascertain the possibility of any partial melting in the vicinity of optimum superplastic temperatures.

  9. Editorial: Cartas al Editor

    Directory of Open Access Journals (Sweden)

    Guillermo Llanos

    2006-06-01

    Full Text Available En todas las revistas biomédicas del mundo existe una sección habitual denominada como el título de este editorial y que en Colombia Médica la llamamos correspondencia. Este espacio tiene como objetivo fundamental que los lectores escriban a los autores (investigadores comentando los artículos que se han publicado en números anteriores de la revista. Las cartas son, entonces, breves comentarios de desacuerdo o acuerdo (conceptual, metodológico, interpretativo sobre falencias ubicadas por un lector alerta al tema debatido en cualquiera de las secciones como en los artículos originales, editoriales, revisiones, presentación de casos, etc. publicados previamente en la revista. Las cartas deben permitir el intercambio de opiniones y formas de pensar y analizar los problemas planteados entre los autores y los lectores. En ocasiones una serie de cartas motivadas por un artículo original puede ser tan o más interesante como el artículo que generó la correspondencia. Las cartas son también un formato adecuado para comunicar un hecho novedoso de una observación clínica juiciosa no descrita antes. Un ejemplo de ello es la carta de un gineco-obstetra australiano cuando informó a Lancet los primeros efectos adversos informados de la talidomida. Colombia Médica, a pesar de mantener vigente esta sección, no ha sido muy afortunada en establecer una buena cultura del envío de cartas al editor. Pero últimamente han llegado juiciosas observaciones a las cuales se les ha dado prioridad en su publicación. Toda carta que comenta los hallazgos de un artículo es enviada a los autores para su respuesta, porque ello genera el debate académico buscado, y luego se publican, tanto la carta como su respuesta. El Estilo Vancouver recomienda que la carta y su respuesta deban ser breve, no pasar de dos o tres párrafos y contener sólo cuatro o cinco referencias. En lo posible (a menos que sea indispensable no presentar ni cuadros ni gráficos. El t

  10. Malamih al-Ashwat al-'Arabiyyah wa Makharijaha

    Directory of Open Access Journals (Sweden)

    Amrah Muhammad Kasim

    2015-12-01

    Full Text Available This writing discusses on al-ashwat al-‘arabiyyah that is known with “phonetic” term. It talks and interprets makharij al-huruf or place for producing sounds and also processing production of sounds by parts of mouth in Arabic language. The problems of sounds and its systems in Arabic language have been conducted by the scholars of al-ashwat al-‘arabiyyah attractively, neatly, and detail and gotten ahead the phonetic western scholars. Part of their analysis results formulate the study about al-ashwat al-sakinah (al-Shamit is known with vocal and consonant sounds in research questions shawait – shawamit. Ibnu Jinni has formulated “harakat”(wowel in Arabic language and dimension of letter  mad and liyn on alif  letter - waw - ya’ (ا و ي, from these letters create  harakat fathah, dammah, and kasrah. Moreover, in this writing also exist the description of hija’i letters and its makhraj that are correct from parts of mouth and the unity of coordinative sounds that produce sounds in morphemes arrangement, in one word that produces meaning. The result of phonological study has divided al-ashwat to be kinds of sound like the pronounced sounds, produced sounds from mouth, and heard sound.

  11. AL-IZDIWAJIYYAH AL-LUGHOWIYAH FII ISTIHDHAMI AL-LUGHOH AL-‘ARABIYAH

    Directory of Open Access Journals (Sweden)

    Imam Muslimin

    2011-10-01

    Full Text Available Al-Izdiwajiyyah (diglosia is standardizing a specific language when there are two variants of language that live side by side in societal life and each variant has its own social function. Disglosia is related to the use of local languages variations of low language and high language in a community. In Arabic language, disglosia covers dialects among the speakers, for instance there are two variants of language that each has roles and functions. The use of the variant depends on the situation. The most important characteristic of diglosia is specifying the functions of wach language variant. For high level language variant is aimed for formal situations such as religious ceremony, lectures, news, or editorials of newspaper. On the contrary, the low level language variant is commonly used in less formal situation such as daily communication in the family, chat with friends, stories in radion, and folk literature. In Arabic language, diglosia can be identified when the speaker of the language use diction commonly used for daily communication (amiyah in a formal expression (fusha, and vice versa.

  12. Al versus Si competition in FeSiAl alloys

    Energy Technology Data Exchange (ETDEWEB)

    Legarra, E. [Dpto. Electricidad y Electronica, Facultad de Ciencia y Tecnologia, Universidad del Pais Vasco (UPV/EHU), CP 644, 48080 Bilbao (Spain)], E-mail: estibaliz.legarra@ehu.es; Apinaniz, E. [Dpto. Fisica Aplicada I, Escuela de Ingenieria Tecnica Superior, Universidad del Pais Vasco, Alameda de Urquijo s/n 48013 Bilbao (Spain); Plazaola, F. [Dpto. Electricidad y Electronica, Facultad de Ciencia y Tecnologia, Universidad del Pais Vasco (UPV/EHU), CP 644, 48080 Bilbao (Spain); Jimenez, J.A. [Centro Nacional de Investigaciones Metalurgicas (CENIM), Avda. Gregorio del amo 8, 28040 Madrid (Spain); Pierna, A.R. [Chemical Engineering and Environmental Department, UPV/EHU, Box 1379, 20008 San Sebastian (Spain)

    2008-10-15

    In FeSiAl alloys, when Si substitutes for Al, important changes take place in the magnetism as well as in the structural properties. Alloys in the two composition series Fe{sub 75}Al{sub 25-x}Si{sub x} (x=0, 7.5, 12.5, 17.5, 25) and Fe{sub 70}Al{sub 30-x}Si{sub x} (x=0, 9, 15, 21, 30) were prepared by induction melting; afterwards they were crushed and then annealed in order to recover the DO{sub 3} stable phase. The deformed FeAl samples show larger lattice parameters than the ordered ones; however, this difference ({delta}a) decreases when Si substitutes for Al until it becomes zero (i.e. until the ordered samples and the deformed ones have the same lattice parameters). This trend is the same for both sample series and does not depend on the Fe content of the alloy. However, the magnetization has a different behaviour depending on the Fe content. For deformed Fe{sub 75}Al{sub 25-x}Si{sub x} alloys the saturation magnetization decreases with increasing Si content while for Fe{sub 70}Al{sub 30-x}Si{sub x} deformed alloys the saturation magnetization has a plateau in which the saturation magnetization values do not vary.

  13. Undulators at the ALS

    International Nuclear Information System (INIS)

    At Lawrence Berkeley Laboratory's (LBL) Advanced Light Source (ALS), three 4.6 m long undulators have been completed, tested and installed. A fourth is under construction. The completed undulators include two 5.0 cm period length, 89 period devices (U5.0s) which achieve a 0.85 T effective field at a 14 mm minimum gap and a 8.0 cm period length, 55 period device (U8.0) that reaches a 1.2 T effective field at a 14 mm minimum gap. The undulator under construction is a 10.0 cm period length, 43 period device (U10.0) that is designed to achieve 0.98 T at a 23 mm gap. Undulator magnetic gap variation (rms) is within 25 microns over the periodic structure length. Reproducibility of the adjustable magnetic gap has been measured to be within +/- 5 microns. Gap adjusting range is from 14 mm to 210 mm, which can be scanned in one minute. The 5.1 m long vacuum chambers are flat in the vertical direction to within 0.74 mm and straight in the horizontal direction to within 0.08 mm over the 4.6 m magnetic structure sections. Vacuum chamber base pressures after UHV beam conditioning are. in the mid 10-11 Torr range and storage ring operating pressures with full current are in the low 10-10 Torr range. Measurements show that the uncorrelated magnetic field errors are 0.23%, and 0.20% for the two U5.Os and the U8.0 respectively and that the field integrals are small over the 1 cm by 6 cm beam aperture. Device description, fabrication, and measurements are presented

  14. Alexandria (Al Iskandariya), Egypt

    Science.gov (United States)

    2002-01-01

    This image of Alexandria was taken by astronauts on board the International Space Station in December 2000 using an Electronic Still Camera. A wider-angle view (STS088-739-90) taken from the Space Shuttle in December 1998 is available for context. Alexandria (Al Iskandariya) occupies a T-shaped peninsula and strip of land separating the Mediterranean from Lake Mariout. Originally the town was built upon a mole (stone breakwater) called Heptastadium, which joined the island of Pharos (see referenced website, below) to the mainland. Since then sedimentary deposits have widened the mole. Since 1905, when the 370,000 Alexandrians lived in an area of about 4 sq km between the two harbors, the city (population 4 million; see referenced website, below) has grown beyond its medieval walls and now occupies an area of about 300 sq km. The Mahmudiya Canal, connecting Alexandria with the Nile, runs to the south of the city and, by a series of locks, enters the harbor of the principal port of Egypt (note ships). The reddish and ochre polygons west of Lake Mariout are salt-evaporation, chemical-storage, and water-treatment ponds within the coastal lagoon. Reference Youssef Halim and Fatma Abou Shouk, 2000, Human impacts on Alexandria's marine environment: UNESCO, Coastal Regions and Small Islands Unit (CSI), Coastal Management Sourcebooks 2 (accessed December 20, 2000) Additional photographs taken by astronauts can be viewed at NASA-JSC's Gateway to Astronaut Photography of Earth. Image ISS001-ESC-5025 provided by the Earth Sciences and Image Analysis Laboratory, Johnson Space Center.

  15. Thermal Modeling of Al-Al and Al-Steel Friction Stir Spot Welding

    Science.gov (United States)

    Jedrasiak, P.; Shercliff, H. R.; Reilly, A.; McShane, G. J.; Chen, Y. C.; Wang, L.; Robson, J.; Prangnell, P.

    2016-09-01

    This paper presents a finite element thermal model for similar and dissimilar alloy friction stir spot welding (FSSW). The model is calibrated and validated using instrumented lap joints in Al-Al and Al-Fe automotive sheet alloys. The model successfully predicts the thermal histories for a range of process conditions. The resulting temperature histories are used to predict the growth of intermetallic phases at the interface in Al-Fe welds. Temperature predictions were used to study the evolution of hardness of a precipitation-hardened aluminum alloy during post-weld aging after FSSW.

  16. Creación de Habilidades y Competencias a través del Empleo de las Nuevas Tecnologías para el Apoyo al Proceso de Aprendizaje (Building Skills and Competences Through the Use of New Techonologies to Support Learning Process

    Directory of Open Access Journals (Sweden)

    Luis Camilo Ortigueira-Sánchez

    2016-03-01

    Full Text Available Spanish abstract En el presente artículo se explora la aplicabilidad, utilidad y factibilidad del uso de las nuevas tecnologías para fomentar el aprendizaje, el autoestudio, y el trabajo en grupo. En especial se hace referencia a las social media tales como Twitter, Prezi u otras y la formación de redes grupales de trabajo. Mediante un cuestionario, se indaga en aquellas herramientas que han sido de mayor interés y que han satisfecho en mayor o menor medida las expectativas de los alumnos con diferentes tecnologías aplicadas a la docencia. Se obtiene además información que corrobora que el empleo de estas unido a otras más tradicionales, como la docencia presencial y las videos conferencias, cobran una mayor importancia en el desarrollo de habilidades imprescindibles para culminar con éxito los estudios; aportando además una competencia necesaria para la futura incorporación al mercado laboral. English Abstract In this paper the applicability, utility and feasibility of using new technology is explored to encourage learning, self-study and group work. In particular reference to social media such as Twitter, Prezi or other group and the formation of networks is done. Through a questionnaire, investigates those tools that have been of greatest interest and have met to a greater or lesser extent the expectations of students with different technologies applied to teaching. Information that corroborates that the use of these together with other more traditional, such as classroom teaching and video conferences are increasingly important for developing essential skills to successfully complete the studies; also providing a necessary competence to obtain further future incorporation into the labor market.

  17. KWIN nu ook als app

    NARCIS (Netherlands)

    Rotgers, G.; Vermeij, I.

    2014-01-01

    KWIN, Kwantitatieve Informatie Veehouderij, verscheen de afgelopen 25 jaar als lijvig handboek, zowel op papier als digitaal. Dit najaar is daar een serie apps bij gekomen, waarmee adviseurs en veehouders zelf saldo- en kostprijsberekeningen kunnen maken. De apps zijn beschikbaar voor de pluimvee-,

  18. Philosophieren als Unterrichtsprinzip im Mathematikunterricht

    Science.gov (United States)

    Meerwaldt, Diana

    Philosophieren und Mathematik scheinen zunächst gegensätzliche Bereiche zu sein, die sich kaum vereinbaren lassen. Dies trifft für eine Auffassung zu, die Philosophieren als "Gerede" disqualifiziert und Mathematik als eine reine "Formelwissenschaft" begreift. Beide Auffassungen werden den Gegenständen nicht gerecht.

  19. Morfometría dental aplicada al análisis de los procesos de diferenciación poblacional en el sudeste de la Región Pampeana y norte de Patagonia durante el Holoceno Tardío

    Directory of Open Access Journals (Sweden)

    Bernal, Valeria

    2005-01-01

    Full Text Available El objetivo del presente trabajo es analizar la variabilidad en la morfometría dental en muestras de restos óseos humanos del SE de la Región Pampeana asignables a distintos momentos del Holoceno tardío y comparar, desde un punto de vista espacial, el grado de similitud morfológica con muestras procedentes del NE de Patagonia (valles de Río Negro y Chubut, San Blas, Isla Gama. Se relevaron los diámetros mesiodistal y bucolingual medidos a nivel del margen cervical en la totalidad de las piezas dentales permanentes correspondientes a 130 individuos de ambos sexos. Las medidas obtenidas fueron empleadas en análisis estadísticos multivariados con el fin de evaluar el grado similitud morfológica entre las muestras. Los resultados obtenidos indican que: 1- hay diferencias entre las muestras procedentes del SE de la Región Pampeana correspondientes al Holoceno tardío inicial y final, caracterizándose estas últimas por un mayor tamaño dental; 2- la muestra del SE de la Región Pampeana correspondiente al Holoceno tardío final presenta mayor similitud morfológica con la muestra más tardía del valle de Río Negro; 3- existen variaciones cronológicas en el tamaño dental entre las muestras procedentes del NE de Patagonia.

  20. El miedo al rey

    Directory of Open Access Journals (Sweden)

    François FORONDA

    2007-01-01

    Full Text Available La peur du roi. Sources et premières réflexions à propos d’une émotion aristocratique dans la Castille du XIVe siècleFace à un roi qui à présent pousse les effets de son ire jusqu’au meurtre pour faire le vide autour de lui et imposer sa différence souveraine, ses parents et les riches hommes, soit les principaux visés par cette politique de l’arbitraire qui enfreint les règles du jeu autant qu’elle contribue à les redéfinir, disent la peur (metus qu’ils ressentent, qu’ils utilisent aussi afin de donner à leur stratégie de pouvoir un fondement légitime. Et l’expression de cette émotion politique, qui tend à se muer en un stéréotype d’un discours aristocratique d’opposition, surtout présente dans les chroniques, mises ici en relation ici avec d’autres sources, notamment des correspondances, marque profondément l’histoire des relations souvent conflictuelles au sein de cette compagnie en définitive très étroite pendant un siècle, de la fin du XIIIe siècle à la fin du XIVe siècle. Cet article se propose d’ébaucher une première réflexion sur le sujet et d’en présenter les principales sources.El miedo al rey. Fuentes y primeras reflexiones acerca de una emoción aristocrática en la Castilla del siglo XIVFrente a un rey que ahora lleva hasta la muerte los efectos de su ira para hacer el vacío entorno a su persona e imponer su soberana, sus parientes y ricos hombres, o sea los principales afectados por esta política de la arbitrariedad que rompe las reglas del juego a la vez que contribuye a redefinirlas, dicen el miedo (metus que sienten, que utilizan también para darle a su estrategia de poder un fundamento legítimo. Y la expresión de esta emoción política, que tiende a convertirse en un estereotipo de un discurso aristocrático de oposición, sobre todo presente en la crónicas, aquí puestas en relación con otras fuentes, en particular cartas, marca profundamente la historia de

  1. Quantum dots formed in InSb/AlAs and AlSb/AlAs heterostructures

    Science.gov (United States)

    Abramkin, D. S.; Rumynin, K. M.; Bakarov, A. K.; Kolotovkina, D. A.; Gutakovskii, A. K.; Shamirzaev, T. S.

    2016-06-01

    The crystal structure of new self-assembled InSb/AlAs and AlSb/AlAs quantum dots grown by molecularbeam epitaxy has been investigated by transmission electron microscopy. The theoretical calculations of the energy spectrum of the quantum dots have been supplemented by the experimental data on the steady-state and time-resolved photoluminescence spectroscopy. Deposition of 1.5 ML of InSb or AlSb on the AlAs surface carried out in the regime of atomic-layer epitaxy leads to the formation of pseudomorphically strained quantum dots composed of InAlSbAs and AlSbAs alloys, respectively. The quantum dots can have the type-I and type-II energy spectra depending on the composition of the alloy. The ground hole state in the quantum dot belongs to the heavy-hole band and the localization energy of holes is much higher than that of electrons. The ground electron state in the type-I quantum dots belongs to the indirect X XY valley of the conduction band of the alloy. The ground electron state in the type-II quantum dots belongs to the indirect X valley of the conduction band of the AlAs matrix.

  2. Predicción numérica del afino de los granos en la zona afectada por la temperatura (ZAC para aportes de multipasadas durante el proceso de soldeo SMAW en el acero al Cr-Mo-V

    Directory of Open Access Journals (Sweden)

    Mazur, Z.

    2002-02-01

    Full Text Available The methodology of prediction of the heat-affected zone (HAZ microstructure in a multiple-bead welds of the two layers of 1.25Cr-1Mo-0.25V steel using SMAW deposition process is presented. A computer program was developed to calculate extension zones of interest of two layer multipass weld-beads HAZ and predict a percentage of HAZ coarse grains refinement for determined welding parameters, preheating temperature and weldbead overlap. The computer model has been validated by experiment depositing a series of two-layer weld-beads getting reasonable concordance of model prediction and measured during experiment structural HAZ distribution. Keywords HAZ microstructure. Numerical simulation. Cr-Mo-V steel. Two-layer multipass weld-beads

    Se presenta una metodología de predicción de las dimensiones de la zonas que ocupan distintos tamaños de grano de la zona afectada por la temperatura (ZAC, en los aportes de multipasadas de dos capas, aplicada al acero de baja aleación 1,25Cr-1Mo-0,25V por el soldeo SMAW. Se desarrolló un programa por ordenador para calcular la extensión de las regiones de distintos tamaños de grano en la ZAC de multipasadas de dos capas y predecir el porcentaje de afino de los granos gruesos de la ZAC para determinados parámetros de soldeo, temperatura de precalentamiento y solapamiento de los cordones. Se llevó a cabo la validación del modelo realizando una comparación con los resultados experimentales aportando varios cordones de soldadura en dos capas, obteniendo una razonable concordancia entre la predicción del modelo y la distribución estructural de la ZAC medida durante el experimento. Palabras clave Microestructura de la ZAC. Simulación numérica. Aceros al Cr-Mo-V. Soldadura SMAW. Cordones múltiples de soldadura de dos capas.

  3. Prólogo al dossier monográfico "La presencia italiana en las Américas"

    Directory of Open Access Journals (Sweden)

    Adriana Cristina Crolla

    2015-01-01

    Full Text Available Pretender elaborar una cartografía de la presencia de los italianos en el continente americano constituye a primera vista una empresa titánica y de resultados siempre aproximativos e incompletos. Pero intentar realizarlo es un desafío que debe asumirse a fin de colocar nuevas piezas en un puzzle inconmensurable, configurado por cantidades de complejas aristas que esperan ser analizadas. La significativa presencia de viajeros e inmigrantes italianos en el continente americano durante los últimos doscientos años -especialmente relevante desde el punto de vista histórico, cultural y humano- permite de forma excepcional estudiar este complejo fenómeno migratorio partiendo del caso concreto del área hispanoamericana y lusófona, tomando para ello como referencia los múltiples ejemplos de interacción entre culturas, al igual que lo que sucedió en América del Norte, donde el arribo de oleadas inmigratorias y los contactos políticos y culturales fueron también sumamente fructíferos.En este sentido, el abordaje de mutuas contaminaciones e interinfluencias a lo largo del tiempo pasa necesariamente por el estudio de fenómenos históricos tan significativos como son las causas y perfiles de la (e(inmigración así como los procesos particulares de inserción en las nuevas territorialidades; la incidencia de la italianidad en corrientes políticas, sociológicas y culturales en los ámbitos de inserción, en las prácticas de lectura y de traducción; o el aporte de creadores italianos y sus descendientes en el campo de la literatura, la filosofía, la ciencia, el arte y la arquitectura. Otro campo de interés es el de la lengua y las investigaciones que se orientan a la detección de italianismos y al estudio de la generación de interlenguas en las variantes del español hispanoamericano, del portugués brasileño, en el inglés norteamericano y en el bilingüismo canadiense. Y todo ello sin descuidar la importancia que la matriz cultural

  4. Aplicación del modelo de Van Hiele al concepto de aproximación local

    OpenAIRE

    Llorens, Jose-Luis

    1996-01-01

    Se ha resuelto el problema abierto de la extensión del modelo de Van Hiele a niveles educativos superiores, fuera del ámbito de la geometría, aportando descriptores de los niveles de razonamiento a una de las manifestaciones del concepto de aproximación local: el de recta tangente a una curva en un punto. Se ha analizado la relación existente entre el modelo de Van Hiele y la duplicidad de imágenes conceptuales de Vinner. La posibilidad de aplicar el modelo a los fundamentos del análisis mate...

  5. Consoer et al PFOS dataset

    Data.gov (United States)

    U.S. Environmental Protection Agency — This ScienceHub entry was developed for the published paper: Consoer et al., 2016, Toxicokinetics of perfluorooctane sulfonate in rainow trout (Oncorhynchus...

  6. EKSKURSO AL CANGYAN-MONTO

    Institute of Scientific and Technical Information of China (English)

    Verkita; de; Li; Shijun

    1999-01-01

    La Pekina Esperanto-Asocio preskaǚ sta-rigis tradicion organizi ekskurson printempe kajaǚtune. En la pasinta jaro, ni ekskursis al In-terna Mongolio kaj habis agrablajn renkontiojnkun geesperantistoj en Huhehot kaj Baotou. i-

  7. DESAFÍOS AL ORDEN

    Directory of Open Access Journals (Sweden)

    Evangelina De los Rios

    2012-03-01

    Full Text Available Fradkin, Raúl y Gelman, Jorge (Compiladores, Desafíos al Orden. Política y sociedades rurales durante la Revolución de Independencia, Prohistoria ediciones, Rosario, 2008, 157 pp.

  8. Seltzer_et_al_2016

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset supports the modeling study of Seltzer et al. (2016) published in Atmospheric Environment. In this study, techniques typically used for future air...

  9. Information als Gegenstand von Informationskompetenz

    OpenAIRE

    Ingold, Marianne

    2011-01-01

    Der Informationsbegriff als zentraler Gegenstand von Informationskompetenz wird in der bibliothekarischen Diskussion in der Regel nicht explizit thematisiert, sondern lässt sich aus Fachliteratur und Bibliothekspraxis nur implizit erschließen. Eine theoretische Beschäftigung mit dem Informationsbegriff ist jedoch unabdingbar, soll das Konzept "Informationskompetenz" auch außerhalb des bibliothekarischen Kontextes verständlich und nutzbar gemacht werden. Im vorliegenden Text, der sich als Beit...

  10. Comportamiento a fatiga del vástago de una prótesis para cadera al caminar//Fatigue behavior stem hip prosthesis for walking

    Directory of Open Access Journals (Sweden)

    Ángel Martínez-Delfín

    2014-01-01

    Full Text Available La prótesis de cadera consiste en sustituir la parte superior fracturada del fémur por una pieza de material biocompatible. Debido a las cargas aleatorias que sobre esta prótesis actúan al caminar la persona injertada, surge la fatiga sobre la prótesis. En este trabajo se realiza el cálculo a fatiga del vástago de una prótesis de caderas fabricada con acero inoxidable austenítico AISI 316L GrQ y de uso actual. Para ellose emplea el método de los elementos finitos, considerando la compleja geometría del vástago, el material y las cargas variables resultantes del caminar de la persona con la prótesis artificial colocada. Se calcula el daño a fatiga que estas cargas provocan en la misma así como el número de pasos que pueden darse, garantizándose una larga vida útil de la prótesis por este concepto de resistencia.Palabras claves: fatiga, prótesis de cadera, ciclo, daño, elementos finitos.______________________________________________________________________________AbstractThe hip prosthesis consists in substituting the fractured femur part by a piece of biocompatible material. Because the random character of loads acting over this prosthesis while person walk, crop up the fatigue on the prosthesis. The fatigue behavior of austenitic stainless steel hips prosthesis is studied in this article. The method of finite elements is used, considering the complex geometry of the part, the material and the variable acting loads, as results of steps of walking person. The fatigue damages are calculated as well as the number of steps that can be given, guarantying a long life of the prosthesis for fatigue resistance concept.Key words: fatigue, hip prosthesis, cycle, damage, finite elements.

  11. Strain sensing with sub-micron sized Al-AlOx-Al tunnel junctions

    OpenAIRE

    Koppinen, P. J.; Lievonen, J. T.; Ahlskog, M.; Maasilta, I. J.

    2009-01-01

    We demonstrate a local strain sensing method for nanostructures based on metallic Al tunnel junctions with AlOx barriers. The junctions were fabricated on top of a thin silicon nitride membrane, which was actuated with an AFM tip attached to a stiff cantilever. A large relative change in the tunneling resistance in response to the applied strain (gauge factor) was observed, up to a value 37. This facilitates local static strain variation measurements down to ~10^{-7}.

  12. Al clamor de les vuvuzeles

    Directory of Open Access Journals (Sweden)

    Javier Olivera Betrán

    2010-09-01

    Full Text Available El Mundial de Futbol de Sud-àfrica ha situat l’Àfrica al mapa mundial i ha mostrat al món el triomf de l’estil de futbol d’Espanya basat en la col·lectivitat, l’esperit d’equip, la humilitat, la cohesió interna i el joc bonic. L’organització africana, seriosa i eficaç, ha sabut mobilitzar i il·lusionar la població del país que ha participat en el mundial des de l’orgull de ser africà, amb l’esperit alegre, festiu i també reivindicatiu de la gent de l’Àfrica. Aquest esdeveniment suposa el llançament de la marca “Sud-àfrica” al món amb un avís clar d’optar a l’organització d’uns primers Jocs Olímpics a Àfrica (potser els de 2020. S’obre una finestra d’esperança al segle xxi per al continent perdut de la mà de l’esport espectacle tan universal, massiu, emocional i mercantil que també es juga a la canxa de la política i de l’economia.

  13. A united refinement technology for commercial pure Al by Al-10Ti and Al-Ti-C master alloys

    International Nuclear Information System (INIS)

    Because flake-like TiAl3 particles in Al-Ti-C master alloys prepared in a melt reaction method dissolve slowly when they are added into Al melt at 720 deg. C, Ti atoms cannot be released rapidly to play the assistant role of grain refinement, leading to a poor refinement efficiency of Al-Ti-C master alloys. A united refinement technology by Al-10Ti and Al-Ti-C master alloys was put forward in this paper. The rational combination of fine blocky TiAl3 particles in Al-10Ti and TiC particles in Al-Ti-C can improve the nucleation rate of α-Al. It not only improves the grain refinement efficiency of Al-Ti-C master alloys, but also reduces the consumption

  14. Conjuntivitis alérgica

    Directory of Open Access Journals (Sweden)

    Alejandro Tello Hernández

    2008-07-01

    Full Text Available La conjuntivitis alérgica es una de las causas más comunesde consulta externa en oftalmología y tiene una muy altarelación con las reacciones alérgicas sistémicas. Lafisiopatología de las reacciones de hipersensibilidad noshace entender los cuadros clínicos característicos de estapatología y sus diferentes grados de severidad. Eldiagnostico diferencial es amplio, sin embargo hay clavesdiagnosticas que nos orientan rápidamente al diagnosticocorrecto. El tratamiento se enfoca en las medidasfarmacológicas y no farmacológicas, utilizándolas enconjunto para disminuir la recurrencia del cuadro y prevenirsecuelas visuales.

  15. Electrowinning Al from Al2S3 in Molten Salt

    NARCIS (Netherlands)

    Xiao, Y.; Van der Plas, D.W.; Bohte, J.; Lans, S.C.; Van Sandwijk, A.; Reuter, M.A.

    2007-01-01

    In order to investigate an alternative process for the production of primary aluminum via a sulfide intermediate, the electrochemical behavior of Al2S3 in molten salt has been studied on a laboratory scale. The effects of electrolyte composition, temperature, and cell design on the cell performance

  16. ALS:A SAIRASTAVAN TOIMINTATERAPIA

    OpenAIRE

    Vuorinen, Johanna

    2013-01-01

    Amyotrofinen lateraali skleroosi on harvinainen, etenevä sairaus. Sairaus surkastuttaa edetessään potilaan tahdonalaisen lihaksiston. Sairauden oireet näkyvät yleensä ensin raajoissa, mutta myös nielun lihaksista alkava bulbaarinen taudinmuoto on mahdollinen. ALS voi myös aiheuttaa frontotemporaalista dementiaa. Sairaus etenee yksilöllisesti, mutta sen kesto on yleensä noin 3-5 vuotta. Keski-Suomen keskussairaalassa ALS:n sairastuneen kuntoutukseen osallistuu moniammatillinen työryhmä, j...

  17. Al-Qaeda Since 911

    OpenAIRE

    Brahimi, Alia

    2012-01-01

    Seconds after smiling at her local MP and shaking his hand, Roshonara Choudhry plunged a knife into his stomach. The attack on Stephen Timms in May 2010 was not the most high profile assault inspired by al- Qaeda, nor was it fatal. It did, however, offer a commentary on the changing nature of the terrorist threat since 9/11, al-Qaeda’s major impact on international relations as well as its major failure, and the intimate, perhaps inevitable, connection between the two.

  18. Andalusian astronomy: al-Zij al-Muqtabis of Ibn al-Kammâd.

    Science.gov (United States)

    Chabás, J.; Goldstein, B. R.

    1994-12-01

    In the twelfth century the Arabic astronomer Ibn al-Kammâd, living in Islamic Spain, composed three sets of astronomical tables, called "zijes". The zijes were largely based on the work of predecessors, going back to Ptolemy on the one hand, and Hindu astronomers on the other. None of his zijes survived in the original Arabic, but a Latin manuscript contains a translation of an apparently complete zij, the "al-Zij al-Muqtabis". This paper examines the body of astronomical knowledge contained in this zij. Specifically, it is shown that one can gain valuable information on the solar theory of the Islamic astronomers from this translation. Furthermore, the theory of lunar and solar eclipses in the work is analyzed, and tables of mean planetary and solar motions are discussed. In addition, tables for the motion of the vernal equinox, star tables, and several topics of Islamic spherical astronomy are examined.

  19. ¿COLOMBIA DEBE APOSTARLE AL SOFTWARE LIBRE, AL DE FUENTE ABIERTA O AL PROPIETARIO?

    Directory of Open Access Journals (Sweden)

    Luis Alberto Girón Murillo

    2014-06-01

    Full Text Available Es complejo para gestores y administradores conocer las implicaciones que la adopción de modelos de desarrollo de software tendría para una región. Este artículo ofrece una evaluación de las implicaciones dinámicas que para el desarrollo de software de una región tendría el apostar de forma excluyente al software libre, al software de fuente abierta y al software propietario. Se desarrolló un modelo de simulación en Vensim de la dinámica de sistemas en donde se evaluaron 3 escenarios: uno en donde se adopta de forma excluyente el software libre, uno en donde se adopta el software propietario y uno en donde se adopta el software de fuente abierta. Se ofrecen descripciones y explicaciones de los resultados que sugieren las potencialidades de cada uno de los modelos de desarrollo evaluados.

  20. Dynamic Modeling of ALS Systems

    Science.gov (United States)

    Jones, Harry

    2002-01-01

    The purpose of dynamic modeling and simulation of Advanced Life Support (ALS) systems is to help design them. Static steady state systems analysis provides basic information and is necessary to guide dynamic modeling, but static analysis is not sufficient to design and compare systems. ALS systems must respond to external input variations and internal off-nominal behavior. Buffer sizing, resupply scheduling, failure response, and control system design are aspects of dynamic system design. We develop two dynamic mass flow models and use them in simulations to evaluate systems issues, optimize designs, and make system design trades. One model is of nitrogen leakage in the space station, the other is of a waste processor failure in a regenerative life support system. Most systems analyses are concerned with optimizing the cost/benefit of a system at its nominal steady-state operating point. ALS analysis must go beyond the static steady state to include dynamic system design. All life support systems exhibit behavior that varies over time. ALS systems must respond to equipment operating cycles, repair schedules, and occasional off-nominal behavior or malfunctions. Biological components, such as bioreactors, composters, and food plant growth chambers, usually have operating cycles or other complex time behavior. Buffer sizes, material stocks, and resupply rates determine dynamic system behavior and directly affect system mass and cost. Dynamic simulation is needed to avoid the extremes of costly over-design of buffers and material reserves or system failure due to insufficient buffers and lack of stored material.

  1. Un controesempio al Modus Ponens

    Directory of Open Access Journals (Sweden)

    Vann McGee

    2011-11-01

    Full Text Available La traduzione dell’articolo è stata resa possibile grazie al consenso dell’autore e del Journal of Philosophy. Riferimenti originali: Vann McGee (1985: “A Counterexample to Modus Ponens”, Journal of Philosophy, Vol. 82, No. 9 (Sep. 1985, pp. 462-47. [N.d.T.

  2. Derecho humano al agua y al saneamiento: derechos estrechamente vinculados al derecho a la vida

    OpenAIRE

    Fernández Aller, Maria Celia; Luis Romero, Elena de; Guzmán Acha, Cristina

    2013-01-01

    Los derechos humanos al agua y al saneamiento están íntimamente relacionados con otros derechos esenciales para la vida, como la alimentación o la salud. Su reconocimiento como derechos humanos en 2010 marca un hito importante en el respeto, protección y realización de estos derechos, que se encuentran seriamente vulnerados para una mayoría de población más vulnerable y empobrecida, sobre todo en el ámbito rural. Mucho camino queda aún para conseguir no sólo la disponibilidad de agua y saneam...

  3. LA NEGOCIACIÓN COOPERATIVA, UNA APROXIMACIÓN AL MODELO HARVARD DE NEGOCIACIÓN

    Directory of Open Access Journals (Sweden)

    Darío Parra Sepúlveda

    2012-12-01

    Full Text Available En el presente trabajo se pretende dar una descripción genérica sobre aquellos conceptos básicos que compondrían la denominada teoría de la negociación cooperativa o también llamada modelo Harvard de negociación, la cual, en términos simples, plantea que ambas partes negociantes vean satisfechos sus intereses, aportando una visión que viene a complementar el modelo clásico de negociación distributiva en el que –por definición– sólo una de las partes ha de lograr beneficios a raíz de las pérdidas que sufre la contraria.

  4. First principles calculation of ac conductance for Al-BDT-Al and Al-Cn-Al systems

    Directory of Open Access Journals (Sweden)

    Jia-Ning Zhuang

    2011-12-01

    Full Text Available We perform first-principles calculation to investigate the dynamic conductance of atomic wires of the benzenedithiol (BDT as well as carbon chains with different length in contact with two Al(100 electrodes (Al-Cn-Al. Our calculation is based on the combination of the non-equilibrium Green's function and the density functional theory. For ac conductance, there are two theories that ensures the current conservation: (1. the global formula which is a phenomenological theory that partitions the total displacement current into each leads so that the current is conserved.(2. the local formula which is a microscopic theory that includes Coulomb interaction explicitly so that the current is conserved automatically. In this work, we use the local formula to calculate the dynamic conductance, especially the emittance. We give a detailed comparison and analysis for the results obtained from two theories. Our numerical results show that the global formula overestimates the emittance by two orders of magnitude. We also obtain an inequality showing that the emittance from global formula is greater than that from local formula for real atomic structures. For Al-Cn-Al structures, the oscillatory behavior as the number of carbon chain N varies from even to odd remains unchanged when local formula is used. However, the prediction of local formula gives rise to opposite response when N is odd (inductive-like as compared with that of global formula. Therefore, one should use the local formula for an accurate description of ac transport in nanoscale structures. In addition, the ‘size effect’ of the ac emittance is analyzed and can be understood by the kinetic inductance. Since numerical calculation using the global formula can be performed in orbital space while the local formula can only be used in real space, our numerical results indicate that the calculation using the local formula is extremely computational demanding.

  5. Personalidad y tolerancia al dolor

    Directory of Open Access Journals (Sweden)

    JESÚS M.ª CARRILLO

    2005-01-01

    Full Text Available Se examina la relación de algunas variables de personalidad -EPQ-A (Eysenck y Eysenck, 1975, NEO-PI (McCrae y Costa, 1988 y STA -personalidad esquizotípica- y STB -personalidad límite-, de Claridge y Broks (1984, con la tolerancia al dolor experimental inducido mediante agua fría (cold pressor test, según el procedimiento de Staats, Heckmat y Staats (1998 en una muestra filtrada mediante un cuestionario sobre dolor crónico, dolores de cabeza, de espalda, artritis, síndrome de Raynaud, y personas bajo medicación. La tolerancia al dolor experimental se evaluó mediante el Umbral del dolor (tiempo en segundos desde la introducción de la mano en el agua hasta el primer informe de dolor, Mantenimiento del dolor (duración en segundos de la inmersión de la mano desde la aparición del umbral hasta su retirada y Tolerancia al dolor (duración total en segundos de la inmersión de la mano desde su introducción hasta su retirada. Un análisis correlacional, factorial y de regresión por pasos mostraron un efecto cruzado entre medidas de ansiedad (tolerancia negativa al dolor y psicoticismo, siendo psicoticismo junto con control emocional predictores de tolerancia positiva al dolor. En cuanto a psicoticismo, parece que son sus elementos de naturaleza paranoide y de "dureza" los que afectan a una percepción atenuada del dolor.

  6. 76 FR 38700 - United States, et al.

    Science.gov (United States)

    2011-07-01

    ... Antitrust Division United States, et al. v. American Express Company, et al.; Public Comments and Response...), the United States hereby publishes below its Response to public comments received on the proposed Final Judgment in United States, et al. v. American Express Company, et al., Civil Action No....

  7. Large rectification magnetoresistance in nonmagnetic Al/Ge/Al heterojunctions.

    Science.gov (United States)

    Zhang, Kun; Li, Huan-Huan; Grünberg, Peter; Li, Qiang; Ye, Sheng-Tao; Tian, Yu-Feng; Yan, Shi-Shen; Lin, Zhao-Jun; Kang, Shi-Shou; Chen, Yan-Xue; Liu, Guo-Lei; Mei, Liang-Mo

    2015-09-21

    Magnetoresistance and rectification are two fundamental physical properties of heterojunctions and respectively have wide applications in spintronics devices. Being different from the well known various magnetoresistance effects, here we report a brand new large magnetoresistance that can be regarded as rectification magnetoresistance: the application of a pure small sinusoidal alternating-current to the nonmagnetic Al/Ge Schottky heterojunctions can generate a significant direct-current voltage, and this rectification voltage strongly varies with the external magnetic field. We find that the rectification magnetoresistance in Al/Ge Schottky heterojunctions is as large as 250% at room temperature, which is greatly enhanced as compared with the conventional magnetoresistance of 70%. The findings of rectification magnetoresistance open the way to the new nonmagnetic Ge-based spintronics devices of large rectification magnetoresistance at ambient temperature under the alternating-current due to the simultaneous implementation of the rectification and magnetoresistance in the same devices.

  8. Al/Au/n-Si/Al surface barrier detector

    International Nuclear Information System (INIS)

    Charged-particle detectors are required to be operated sometimes in ambient light for applications like alpha counting and range finding. Detectors like Al/p-Si surface barrier with aluminium on the front side are found quite suitable. Gold/n-Si surface barrier detectors are not usable because of their excessive background photo current. These detectors, we fabricate for use in nuclear experiments, were given an aluminium coating on their gold side for use in room light. The Au/n-Si/Al surface barrier diodes were characterized for their electrical properties and performance as alpha detectors. Detectors showing good energy resolution (∼ 50 KeV) were selected and provided with another thin reflecting coat of aluminium on their front sides

  9. Al-Anon and recovery.

    Science.gov (United States)

    Cermak, T L

    1989-01-01

    The history of Al-Anon and its current demographics are reviewed. In order to understand 12-step recovery and psychotherapy for family members of alcoholics, the concept of codependence is defined with a set of diagnostic criteria consistent with the DSM-III-R definition of personality traits and disorders. At the core of codependence are denial and an unrealistic relationship to willpower. The therapeutic implications of considering codependence as a personality disorder are explored, as are the characteristics that make codependence unique among personality disorders: the central role of denial and the existence of a self-help organization to facilitate recovery. The dynamics of working the 12 steps on codependent characteristics are outlined. A synergistic relationship between psychotherapy and the 12 steps is described. Special attention is given the emergence of Al-Anon adult children of alcoholic meetings, and the future of codependence is discussed.

  10. Sui controesempi al Modus Ponens

    Directory of Open Access Journals (Sweden)

    Giorgio Sbardolini

    2011-11-01

    Full Text Available In McGee (1985 si presentano tre controesempi al modus ponens (MP, e si argomenta di come esistano restrizioni alla validità di questa regola deduttiva. Nel presente articolo, intendo ridiscutere questi tre controesempi a MP mostrando perché non colgono il bersaglio, e presentare altri casi in cui l'applicazione di MP non sembra efficace.In [McGee, 1985] si presentano 3 controesempi al modus ponens (MP, e si argomenta di come esistano restrizioni alla validità di questa regola deduttiva. Nel presente articolo, intendo ridiscutere questi 3 controesempi a MP mostrando perché non colgono il bersaglio, e presentare altri casi in cui l'applicazione di MP non sembra efficace.

  11. Al Margen de las Cooperativas

    Directory of Open Access Journals (Sweden)

    Gutiérrez Estrada Julio

    1941-04-01

    Full Text Available El sistema Cooperativista, propiamente hablando, no viene a constituir una doctrina económica, es más bien una práctica, un modo de proceder en provecho de determinada agrupación de individuos que se asocian para defenderse de la usura del comercio y del intermediarismo parasitario. "El movimiento cooperativo es tan viejo como la revolución industrial, y ha crecido paralelamente a ella, podría decirse como una protesta en contra del sistema capitalista industrial. Generalmente se considera que tres principios fundamentales determinan su carácter distintivo. 1-Se esfuerza por dar "servido al costo" a sus miembros antes que beneficiarse del negocio con el público en general. El servicio de un grupo organizado se considera como un medio para obtener el máximum de eficacia con mínimo de desperdicio. 2-Insiste en que los beneficios pecuniarios se distribuyan al miembro como productor, después de deducir solamente el interés del capital al tipo que compite, y los salarios y jornales de los trabajadores. 3-Mantiene el control democrático del negocio por todos los participantes en él".

  12. Vormundschaftsrecht als Grundlage politischer Herrschaft

    Directory of Open Access Journals (Sweden)

    Arne Duncker

    2006-07-01

    Full Text Available In ihrer beachtlichen und sehr gewissenhaft dokumentierten Arbeit über vormundschaftliche Regentschaften im 16. und 17. Jahrhundert beschreibt Pauline Puppel unter ausführlichem Bezug auf zeitgenössische Literatur und Archivalien sowohl die allgemeine Rechtslage im damaligen Reich als auch die Anwendungsfälle in Hessen, wo zwischen 1500 und 1700 insgesamt viermal eine Landgräfin als Vormünderin des Fürsten zur Regentin ihres Landes wurde. Dies steht exemplarisch für eine bereits in der Frühen Neuzeit mögliche und nicht einmal ganz seltene Form politischer Frauenherrschaft, die bisher oft nicht hinreichend gewürdigt wurde. Puppels Untersuchung ist in zwei Hauptteile gegliedert. Der erste Teil (Das juristische Regelwerk“, S. 34-143 behandelt die zeitgenössischen Rahmenbedingungen der durch Frauen ausgeübten Vormundschaft und Regentschaft. Der zweite Abschnitt („Die Landgräfinnen von Hessen als Regentinnen“, S. 144-307 befasst sich mit der Ausfüllung dieser Regeln durch konkrete Fallbeispiele in Gestalt von Leben und Regentschaft der regierenden Landgräfinnen von Hessen.

  13. Prólogo al dossier monográfico "La presencia italiana en las Américas"

    OpenAIRE

    Adriana Cristina Crolla

    2015-01-01

    Pretender elaborar una cartografía de la presencia de los italianos en el continente americano constituye a primera vista una empresa titánica y de resultados siempre aproximativos e incompletos. Pero intentar realizarlo es un desafío que debe asumirse a fin de colocar nuevas piezas en un puzzle inconmensurable, configurado por cantidades de complejas aristas que esperan ser analizadas. La significativa presencia de viajeros e inmigrantes italianos en el continente americano durante los últim...

  14. Microstructure of interaction interface between Al-Si, Zn-Al alloys and Al2O3p/6061Al composite

    Institute of Scientific and Technical Information of China (English)

    许志武; 闫久春; 吕世雄; 杨士勤

    2004-01-01

    Interaction behaviors between Al-Si, Zn-AI alloys and Al2O3p/6061AI composite at different heating temperatures were investigated. It is found that Al2O3p/6061Al composite can be wetted well by AlSi-1, AlSi-4 and Zn-Al alloys and an interaction layer forms between the alloy and composite during interaction. Little Al-Si alloys remain on the surface when they fully wet the composite and Si element in Al-Si alloy diffuses into composite entirely and assembles in the composite near the interface of Al-Si alloy/composite to form a Si-rich zone. The microstructure in interaction layer with Si penetration is still dense. Much more residual Zn-Al alloy exists on the surface of composite when it wets the composite, and porosities appear at the interface of Zn-Al alloy/composite. The penetration of elements Zn, Cu of Zn-Al alloy into composite leads to the generation of shrinkage cavities in the interaction layer and makes the microstructure of Al2 O3p/6061A1 composite loose.

  15. Armaflex in Burj al Arab; Armaflex im Burj al Arab

    Energy Technology Data Exchange (ETDEWEB)

    Steiner, B.

    2003-07-01

    This article describes the Burj al Arab in Dubai, the unique seven-star high-rise hotel. The construction of the hotel, that is built on 250 piles driven into the sand of an artificial island in the Persian Gulf, is described. In particular, various special materials used in the building are described, as are the luxurious fittings and furnishings of the hotel. The cooling and air-conditioning installations that are necessary as a result of the desert climate of Dubai are described and the use of 'Armaflex' elastomer insulating material for the insulation of refrigeration machines and cold-water piping is discussed.

  16. Memahami Tasawuf Ibnuu Arabi dan Ibnuu al Farid: Konsep al Hubb Illahi, Wahdat al Wujud, Wahdah al Syuhud dan Wahdat al Adyan

    Directory of Open Access Journals (Sweden)

    Muhammad Robith Fuadi

    2013-12-01

    Full Text Available Kaum sufi menapaki jalan yang berbeda untuk menuju hakikat, mereka tidak menggunakan akal dan rasio untuk sampai pada hakikat. Akan tetapi, akal bukan satu-satunya jalan untuk menuju hakikat. Karena kita sering melihat sesuatu yang di luar jangkauan akal dalam hidup ini. Jalan yang ditempuh kaum sufi untuk menuju hakikat seperti kasyf, dzauq, 'iyan, musyahadah dan sebagainya dinilai sebagai sesuatu yang samar, tidak mempunyai batasan dan kaidah pasti, bahkan sering kali bercampur dengan igauan, mimpi, khayalan dan angan-angan. Tapi yang perlu kita ingat adalah bahwa media-media tersebut telah mampu menuntun manusia untuk memecahkan sesuatu yang tidak bisa dipecahkan oleh akal dan hukum-hukum fisika. Tulisan ini akan mengkaji gagasan-gagasan dua tokoh tasawuf besar yaitu Ibnu Arabi dan Ibnu al-Farid yang hidup  pada abad keenam dan ketujuh Hijriah. Tulisan ini secara spesifik akan mengkaji tiga gagasan penting ke dua tokoh tersebut. Yaitu al hubb al Ilahi, wahdat al Wujud dan wahdat al adyan.

  17. Electrical conductivity of (Na3AlF6-40%K3AlF6)-AlF3-Al2O3 melts

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The effects of contents of AlF3 and Al2O3,and temperature on electrical conductivity of (Na3AlF6-40%K3AlF6)-AlF3-Al2O3 were studied by continuously varying cell constant (CVCC) technique.The results show that the conductivities of melts increase with the increase of temperature,but by different extents.Every increasing 10 ℃ results in an increase of 1.85×10-2,1.86×10-2,1.89×10-2 and 2.20×10-2 S/cm in conductivity for the (Na3AlF6-40%K3AlF6)-AlF3 melts containing 0%,20%,24%,and 30% AlF3,respectively.An increase of every 10 ℃ in temperature results an increase about 1.89×10-2,1.94×10-2,1.95×10-2,1.99×10-2 and 2.10×10-2 S/cm for (Na3AlF6-40%K3AlF6)-AlF3-Al2O3 melts containing 0%,1%,2%,3% and 4% A12O3,respectively.The activation energy of conductance was calculated based on Arrhenius equation.Every increasing 1% of AlF3 results in a decrease of 0.019 and 0.020 S/cm in conductivity for (Na3AlF6-40%K3AlF6)-AIF3 melts at 900 and 1 000 ℃,respectively.Every increase of 1% Al2O3 results in a decrease of 0.07 S/cm in conductivity for (Na3AlF6-40%K3AlF6)-AlF3-Al2O3 melts.The activation energy of conductance increases with the increase in content of AlF3 and Al2O3.

  18. United modification of Al-24Si alloy by Al-P and Al-Ti-C master alloys

    Institute of Scientific and Technical Information of China (English)

    韩延峰; 刘相法; 王海梅; 王振卿; 边秀房; 张均艳

    2003-01-01

    The modification effect of a new type of Al-P master alloy on Al-24Si alloys was investigated. It is foundthat excellent modification effect can be obtained by the addition of this new type of A1-P master alloy into Al-24Simelt and the average primary Si grain size is decreased below 47 μm from original 225 μm. It is also found that theTiC particles in the melt coming from Al8Ti2C can improve the modification effect of the Al-P master alloy. Whenthe content of TiC particles in the Al-24Si melt is 0.03 %, the improvement reaches the maximum and keeps steadywith increasing content of TiC particles. Modification effect occurs at 50 min after the addition of the Al-P master al-loy and TiC particles, and keeps stable with prolonging holding time.

  19. Description of hypoeutectic Al-Si-Cu alloys based on their known chemical compositions

    Directory of Open Access Journals (Sweden)

    Djurdjevic, M. B.

    2013-10-01

    interés durante las últimas décadas, y la cantidad de programas de simulación existentes en el mercado es un buen indicador del interés de la industria en este campo. La mayoría de los datos empleados en estos programas se basan en los diagramas de fase binarios, ternarios o incluso superiores. Desafortunadamente, excepto para los diagramas binarios, el ajuste de los datos no es lo suficiente bueno. Teniendo en cuenta que la mayoría de los sistemas binarios del aluminio están bien definidos se ha intentado convertir los sistemas multi-componentes en un pseudo binario sistema Al-Xi (en este caso el diagrama de fase Al-Si es el elegido como sistema de referencia. El nuevo algoritmo del Silicio Equivalente (SiEQ expresa la cantidad de los elementos de la aleación que son mayoritarios y minoritarios, a través de una cantidad “equivalente” de silicio. Este sistema puede emplearse para calcular varias características termo-físicas y de solidificación de sistemas multicomponentes, como las aleaciones de aluminio. Esto permite al modelo tener la capacidad de realizar predicciones de las características de la solidificación de las piezas fundidas, donde las velocidades de enfriamiento son bajas y las características del proceso de solidificación son bien conocidas, para evitar posibles problemas en la fundición. Este trabajo demuestra cómo el algoritmo del SiEQ puede ser empleado para el cálculo de las características de las temperaturas de solidificación de las aleaciones multi-componentes Al-Si, así como sus calores latentes y el factor de restricción del crecimiento del grano. El análisis estadístico de los resultados obtenidos en un amplio rango de composiciones químicas de la aleación, muestra una muy buena correlación entre los datos experimentales y los cálculos realizados con el SiEQ. La misma aproximación matemática podría ser aplicada para otros sistemas metálicos como el hierro y el magnesio, empleando el carbono equivalente en el

  20. Ce对Al-Si-Cu合金中α(Al)-Al2Cu共晶形貌的影响%Effect of Ce on morphology ofα(Al)-Al2Cu eutectic in Al-Si-Cu alloy

    Institute of Scientific and Technical Information of China (English)

    Maja VONINA; Joef MEDVED; Tonica BONINA; Franc ZUPANI

    2014-01-01

    The effect of Ce addition on the morphology of the α(Al)-Al2Cu eutectic in Al-Si-Cu alloy was investigated using thermal analysis, light microscopy, scanning electron microscopy, focused ion beam and energy dispersive analysis. The results show that the eutectic α(Al)-Al2Cu forms within small space between dendrites, silicon and AlSiFeMn plates. Eutectic Al2Cu is not lamellar but degenerated. However, Al2Cu in Ce-modified alloys is more compact. Ce partially dissolves in Al2Cu, which is a viable reason for the formation of coarser Al2Cu. The addition of Ce also increases the microhardness of theα(Al)-Al2Cu eutectic by almost 10%compared with the basic Al-Si-Cu alloy.%采用热分析、光学显微镜技术、扫描电镜技术、聚焦离子束和能量色散谱分析方法研究Ce对Al-Si-Cu合金中α(Al)-Al2Cu共晶形貌的影响。结果表明,在枝晶、硅和AlSiFeMn之间较小空间内形成了α(Al)-Al2Cu共晶。Al2Cu为非层状的不规则共晶组织。Al2Cu在经Ce改性的合金中更加致密。部分Ce溶解于Al2Cu中,这是粗晶Al2Cu形成的原因。与基体Al-Si-Cu合金相比,Ce的加入能使α(Al)-Al2Cu共晶合金的显微硬度提高约10%。

  1. Respuesta al Desgaste de un Material de Aluminio Reforzado con Circonia Response to wear of an Aluminum Material Reinforced with Zirconia

    Directory of Open Access Journals (Sweden)

    Rosalba Fuentes

    2006-01-01

    Full Text Available Se desarrolló un material compuesto aluminio-circonia por metalurgia de polvos. Los polvos de circonia fueron sintetizados por sol-gel, se mezclaron con polvo de aluminio, se compactaron y se sinterizaron. El tamaño del polvo de aluminio utilizado fue menor a 100 micras. La circonia tuvo como material precursor al n-propóxido de circonio. Se prepararon varias mezclas con ambos polvos, utilizando tres proporciones de circonia de 1%, 3% y 5% en peso. Se aplico una compactación de 58 KN y se sinterizó a 610°C. Posteriormente las piezas fueron sometidas a pruebas de desgaste con objeto de analizar su respuesta. El desgaste se realizó en una máquina de pin-en-disco, con velocidad de 320 rpm y presión de desgaste 9 KN por un período de dos horas. Las pruebas de desgaste muestran el comportamiento tribológico del material compuesto observándose un au>mento de resistencia al desgaste cuando el porcentaje en peso de circonia se incrementa.An aluminum-zirconia composite was developed using powder metallurgy. Zirconia powder was synthesized by a sol-gel method, mixed with aluminum powder, and was compacted and sinterized. The particle size of the aluminum powder utilized was less than 100 microns. The precursor material of zirconia was an n-propoxide of zirconium. Different proportions of zirconia were used in three mixtures at 1%, 3% and 5% by weight. The mixtures were compacted at 58KN and were sinterized at 610°C. Subsequently, the pieces were subjected to wear resistance tests to determine their resistance. The wear test was carried out in a pin-in-disk machine at a speed of 320 rpm and load of 9 KN for a period of two hours. The wear resistance tests showed the tribologic behavior of this composite showing an increase in wear resistance when the weight percentage of zirconia increases.

  2. Reply to Pachai et al.

    Science.gov (United States)

    Harrison, William J; Bex, Peter J

    2016-05-01

    Peripheral vision is fundamentally limited by the spacing between objects. When asked to report a target's identity, observers make erroneous reports that sometimes match the identity of a nearby distractor and sometimes match a combination of target and distractor features. The classification of these errors has previously been used to support competing 'substitution' [1] or 'averaging' [2] models of the phenomenon known as 'visual crowding'. We recently proposed a single model in which both classes of error occur because observers make their reports by sampling from a biologically-plausible population of weighted responses within a region of space around the target [3]. It is critical to note that there is no probabilistic substitution or averaging process in our model; instead, we argue that neither substitution nor averaging occur, but that these are misclassifications of the distribution of reports that emerge when a population response distribution is sampled. This is a fundamentally different way of thinking about crowding, and on this basis we claim to have provided a mechanism unifying categorically distinct perceptual errors. Our goal was not to model all crowding phenomena, such as the release from crowding when target and flanks differ in color or depth [4]. Pachai et al.[5] have suggested that our model is not unifying because it inaccurately predicts perceptual performance for a particular stimulus. Although we agree that our model does not predict their data, this specific demonstration overlooks the critical aspect of the model: perceptual reports are drawn from a weighted population code. We show that Pachai et al.'s [5] own data actually provide evidence for the population code we have described [3], and we suggest a biologically-plausible analysis of their stimuli that provides a computational basis for their 'grouping' account of crowding.

  3. Reply to Pachai et al.

    Science.gov (United States)

    Harrison, William J; Bex, Peter J

    2016-05-01

    Peripheral vision is fundamentally limited by the spacing between objects. When asked to report a target's identity, observers make erroneous reports that sometimes match the identity of a nearby distractor and sometimes match a combination of target and distractor features. The classification of these errors has previously been used to support competing 'substitution' [1] or 'averaging' [2] models of the phenomenon known as 'visual crowding'. We recently proposed a single model in which both classes of error occur because observers make their reports by sampling from a biologically-plausible population of weighted responses within a region of space around the target [3]. It is critical to note that there is no probabilistic substitution or averaging process in our model; instead, we argue that neither substitution nor averaging occur, but that these are misclassifications of the distribution of reports that emerge when a population response distribution is sampled. This is a fundamentally different way of thinking about crowding, and on this basis we claim to have provided a mechanism unifying categorically distinct perceptual errors. Our goal was not to model all crowding phenomena, such as the release from crowding when target and flanks differ in color or depth [4]. Pachai et al.[5] have suggested that our model is not unifying because it inaccurately predicts perceptual performance for a particular stimulus. Although we agree that our model does not predict their data, this specific demonstration overlooks the critical aspect of the model: perceptual reports are drawn from a weighted population code. We show that Pachai et al.'s [5] own data actually provide evidence for the population code we have described [3], and we suggest a biologically-plausible analysis of their stimuli that provides a computational basis for their 'grouping' account of crowding. PMID:27166690

  4. The Al-Al3Ni Eutectic Reaction: Crystallography and Mechanism of Formation

    Science.gov (United States)

    Fan, Yangyang; Makhlouf, Makhlouf M.

    2015-09-01

    The characteristics of the Al-Al3Ni eutectic structure are examined with emphasis on its morphology and crystallography. Based on these examinations, the mechanism of formation of this technologically important eutectic is postulated. It is found that a thin shell of α-Al forms coherently around each Al3Ni fiber. The excellent thermal stability of the Al-Al3Ni eutectic may be attributed to the presence of this coherent layer.

  5. Formaline of alternatieven als ontsmettingsmiddel voor broedeieren

    OpenAIRE

    Meijerhof, R.; Dijk, D. van

    1997-01-01

    Formaline wordt algemeen gezien als een goed middel om broedeieren te ontsmetten. Toch geeft ontsmetting met middelen als ozon en waterstofperoxyde vaak een iets beter broedresultaat. Een eventuele verklaring hiervoor is momenteel nog niet te geven.

  6. Grainreifnementlimit of commercialpureAl inoculatedbyAl-Ti-C(B)masteralloys

    Institute of Scientific and Technical Information of China (English)

    En-zhao Wang; Xiang-fa Liu

    2015-01-01

    The grain reifnement limits of commercial pure Al inoculated by Al-5Ti-1B, Al-5Ti-0.25C and Al-5Ti-0.3C-0.2B master al oys were studied, and the inlfuence of melting temperature on the grain reifning performance of these three master al oys was investigated using a high scope video microscope (HSVM), a ifeld-emission scanning electron microscope (FESEM), an electron probe micro-analyzer (EPMA) and X–ray diffraction (XRD) method. Results show that there is a grain reifnement limit of commercial pure Al reifned by these three master al oys; with the same addition level of 1.5% under the present experimental conditions, the grain reifnement limits (smal est average grain size) of commercial pure Al reifned by Al-5Ti-1B, Al-5Ti-0.25C and Al-5Ti-0.3C-0.2B master al oys are 50 µm, 80 µm and 80 µm, respectively. In addition, with an increase in the melting temperature of the pure Al, the grain reifning performance of Al-5Ti-1B and Al-5Ti-0.25C master al oys decreases, but the grain reifning performance of Al-5Ti-0.3C-0.2B changes little.

  7. Betaalde arbeid als verdringer van vrijwilligerswerk? Overbelasting als mogelijke verklaring

    Directory of Open Access Journals (Sweden)

    Angela Kok-Van Meer

    2014-06-01

    Full Text Available Do paid work activities displace volunteering? A potential explanation from role overload theoryRecent changes in Dutch society might lead to a shortage of volunteers. On the one hand, the demand for volunteers is increasing: in the social welfare domain because of governmental austerity policies and in other domains such as sports because of the higher supervision intensity of activities. On the other hand, the supply of volunteers is likely to decrease as more and more women and older workers are active in the labor market, which reduces the time that is available for volunteering. Role overload theory would suggest that the increasing labor participation rate of certain categories of workers goes along with a decline of participation in voluntary work. The secondary data analysis shows that various role loads (work, care for children living at home are associated with differences in participation in voluntary work. However, while a higher number of contractual work hours and hours spent on work-related training are negatively associated with volunteer work, care for children living at home is positively associated with volunteering. These results provide only limited support for role overload theory.Betaalde arbeid als verdringer van vrijwilligerswerk? Overbelasting als mogelijke verklaringDe afgelopen jaren hebben zich enkele maatschappelijke veranderingen voorgedaan, die wellicht tot schaarste op de Nederlandse vrijwilligersmarkt zouden kunnen leiden. Enerzijds neemt de vraag naar vrijwilligers toe doordat subsidieregelingen versoberen (bijvoorbeeld in zorg en welzijn en de begeleidingsintensiteit in bepaalde organisaties stijgt (bijvoorbeeld in sport. Anderzijds neemt het aanbod van vrijwilligers af doordat vrouwen en ouderen meer en langer op de arbeidsmarkt actief zijn, waardoor minder tijd beschikbaar is voor vrijwilligerswerk. In dit artikel wordt aan de hand van de role overload theorie nagegaan of het al dan niet deelnemen aan

  8. AlON-SiAlON复合材料的制备及特性%Preparation and properties of AlON-SiAlON composites

    Institute of Scientific and Technical Information of China (English)

    山下敬; 山口明良

    2003-01-01

    为提高AlON陶瓷材料的抗氧化性能,制备了AlON-SiAl7O2N7复相材料.在1750℃、0.5 MPa的N2气氛中,保温2 h烧成不同Al2O3/AlN/Si3N4配比的原料得到不同AlON/SiAl7O2N7比的复相材料.因为在烧结SiAl7O2N7的过程中,蒸发-凝聚的同时伴随着SiO气体的挥发,因此很难得到致密的AlON-SiAl7O2N7复相材料.研究了AlON-SiAl7O2N7复相材料在1300℃、空气中的抗氧化性能,同时作为比较,研究了相同条件下单相的AlON材料的抗氧化性能.结果表明,AlON-SiAl7O2N7复相材料显示了较之单相的AlON陶瓷材料更好的抗氧化性能,这是因为氧化过程中所形成的含玻璃相的表面氧化层抑制了氧的向内扩散所致.

  9. con bajo peso al nacer

    Directory of Open Access Journals (Sweden)

    Adriana Mora Antó

    2005-01-01

    Full Text Available Esta investigación dio cuenta de la relación entre el estilo de funcionamiento familiar, los patrones de crianza y las edades de desarrollo evolutivo en niños, nacidos con bajo peso. El estudio descriptivo correlacional se realizó con 41 niños y sus madres, aplicándose cuestionarios sobre funcionamiento familiar, prácticas de crianza y desarrollo infantil. Los resultados señalaron la existencia de un funcionamiento familiar caracterizado por una cohesión amalgamada y una adaptabilidad caótica, una disciplina complaciente, falta de control y de límites claros en la díada madre-hijo. Se trataba de familias monoparentales, donde la temprana edad de concepción, el madresolterismo y el apoyo de la familia extensa eran constantes. Las edades evolutivas registradas indicaron un desarrollo inferior a la edad cronológica, en la mayor parte de los casos; sin embargo, éstas tendieron a ser superiores al compararlas con la edades reales de los infantes. No se encontró una correlación estadísticamente significativa entre la edad de desarrollo y los diferentes factores del funcionamiento familiar para algunos de los rangos de edad considerados; sin embargo, no se lo descartó por completo, especialmente en lo referente al optimismo familiar

  10. Topiramat als Phasenprophylaktikum - ein Fallbericht

    Directory of Open Access Journals (Sweden)

    Letmaier M

    2001-01-01

    Full Text Available Topiramat ist ein neues Antiepileptikum mit einem breiten Wirkspektrum. Aktuelle klinische Studien geben Hinweise darauf, daß Topiramat stimmungsstabilisierende Eigenschaften besitzt und somit effizient in der Behandlung der bipolaren affektiven Störung sein könnte. Vor dem Hintergrund dieser Studienberichte, behandelten wir eine 41jährige, erstmals vor 10 Jahren erkrankte Patientin mit der Diagnose einer therapierefraktären, bipolaren affektiven Störung (Rapid-Cycling mit Topiramat. Im Rahmen ihrer Erkrankung wurde die Patientin insgesamt 12mal stationär aufgenommen und meist aufgrund von akuten manischen Episoden behandelt. Dabei kamen seit 1991 folgende Phasenprophylaktika zur Anwendung: Carbamazepin, Valproat und Lamotrigin ? zuletzt nur mit mäßigem Erfolg. Daraufhin wurde zu Beginn einer neuerlichen manischen Episode ambulant eine Therapie mit Topiramat begonnen. Acht Wochen nach Therapiestart kam die Patientin in stationäre Behandlung. Der Aufenthalt dauerte weniger als drei Wochen; Topiramat wurde von der Patientin gut vertragen. Infolge eines belastenden Lebensereignisses kam es unter kontinuierlicher Therapie mit Topiramat zu einer Destabilisierung des psychischen Zustandsbildes (manische Symptome. Durch eine ambulante Erhöhung der Topiramatdosis bei gleichzeitiger Gabe von Risperidon und Clonazepam konnte jedoch eine neuerliche manische Episode erstmals ambulant behandelt werden. Die Patientin erhält derzeit 200 mg Topiramat pro Tag und ist seit mehr als 20 Monaten nahezu beschwerdefrei.

  11. Nonstoichiometry of Al-Zr intermetallic phases

    Energy Technology Data Exchange (ETDEWEB)

    Radmilovic, V.; Thomas, G.

    1994-06-01

    Nonstoichiometry of metastable cubic {beta}{prime} and equilibrium tetragonal {beta} Al-Zr intermetallic phases of the nominal composition Al{sub 3}Zr in Al-rich alloys has been extensively studied. It is proposed that the ``dark contrast`` of {beta}{prime} core in {beta}{prime}/{sigma}{prime} complex precipitates, in Al-Li-Zr based alloys, is caused by incorporation of Al and Li atoms into the {beta}{prime} phase on Zr sublattice sites, forming nonstoichiometric Al-Zr intermetallic phases, rather than by Li partitioning only. {beta}{prime} particles contain very small amounts of Zr, approximately 5 at.%, much less than the stoichiometric 25 at.% in the Al{sub 3}Zr metastable phase. These particles are, according to simulation of high resolution images, of the Al{sub 3}(Al{sub 0.4}Li{sub 0.4}Zr{sub 0.2}) type. Nonstoichiometric particles of average composition Al{sub 4}Zr and Al{sub 6}Zr are observed also in the binary Al-Zr alloy, even after annealing for several hours at 600{degree}C.

  12. Electroplating Zn-Al Alloy Technology

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The method of controlling separating anode and separating power source was used to perform orthogonal optimization for the parameters in electroplating Zn-Al alloy.The electroplating Zn-Al alloy technology was decided, in which the content of Al is about 12%-15%.

  13. Cenomanian-Turonian biostratigraphy of the Jardas Al Abid area, Al Jabal Al Akhdar, northeast Libya

    Science.gov (United States)

    El Qot, Gamal M.; Abdulsamad, Esam O.

    2016-09-01

    The Upper Cenomanian-Turonian succession exposed at Jardas al'Abid area consists mainly of carbonates with siliciclastic intercalations. This succession is subdivided lithostratigraphically into: Qasr al'Abid (Late Cenomanian) and Al Baniyah (Late Cenomanian-Coniacian) formations. This sequence is relatively rich in macrofossil assemblages especially bivalves, gastropods, and echinoids with rare ammonites. Based on the first occurrence (FO) and last occurrence (LO) of some index species of these macrofossil groups, an integrated biostratigraphic framework has been constructed. The studied Cenomanian-Turonian sequence is subdivided biostratigraphically into three ammonite biozones; Pseudaspidoceras pseudonodosoides Total Range Zone, Choffaticeras segne Total Range Zone, and Coilopoceras requienianum Total Range Zone. Based on the rest of macrofossil assemblages other than the ammonites, eight biozones were recognized; Mecaster batnensis Total Range Zone, Ceratostreon flabellatum-Neithea dutrugei Acme Zone, Costagyra olisiponensis Acme Zone, Pycnodonte (Phygraea) vesicularis vesiculosa Acme Zone, Mytiloides labiatus Total Range Zone = Mecaster turonensis Acme Zone, Rachiosoma rectilineatum-Curvostrea rouvillei-Tylostoma (T.) globosum Assemblage Zone, Radiolites sp.-Apricardia? matheroni Total Range Zone, and Nerinea requieniana Total Range Zone. Most of the proposed biozones are recorded for the first time from Libya. The integration among these biozones as well as local and inter-regional correlation of the biozones have been discussed. The stage boundaries of the studied stratigraphic intervals are discussed, where the Cenomanian/Turonian boundary is delineated at the last occurrence (LO) of Pseudaspidoceras pseudonodosoides (Choffat), while the Turonian/Coniacian boundary is delineated arbitrary being agree with the LO of the Turonian fauna.

  14. Progresses in analyzing 26Al with SMCAMS

    International Nuclear Information System (INIS)

    Shanghai Mini-Cyclotron based Accelerator Mass Spectrometer (SMCAMS) was especially designed for analyzing 14C. In order to accelerate and analyze 26Al the accelerated orbit and beam optics in injection system were calculated and harmonic number and acceleration turns was optimized. Preliminary experiment was carried out. In which a beam current of 1.15 x 10-9A for 27Al- and 0.038 CPS background for 26Al were measured. The limited sensitivity of 26Al/27Al is 5.25 x 10-12. (authors)

  15. Trato verbal paterno al adolescente

    Directory of Open Access Journals (Sweden)

    Rodríguez Juan Carlos

    1995-06-01

    Full Text Available

    En alguna ocasión se ha escuchado una palabra, que causa un sentimiento y a la vez un recuerdo, que lleva a evocar la adolescencia o la infancia, se recuerda quien la pronunciaba y en que ocasión la decía. Este es el poder que tiene una palabra y más aún si es dicha por el padre, puesto que este es la figura significativa que se lleva en la memoria. De aquí nace el interés de realizar un estudio, en donde se describe y analice la percepción y el sentimiento del adolescente, quien en esta etapa es vulnerable al cambio, ya que está buscando su propia identidad; que con el trato verbal paterno la encontrara sin ninguna dificultad o por el contrario nunca la encontrará.

     

  16. Entscheidung als Häresie

    Directory of Open Access Journals (Sweden)

    Jaanus Sooväli

    2014-06-01

    Full Text Available Man könnte sagen, dass Aristoteles so etwas wie eine traditionelle und dominierende Auffassung der Entscheidung in der westlichen Philosophie gründet. Das Ziel dieses Aufsatzes ist es, diese Auffassung von Aristoteles zu entwerfen, einige ihrer wichtigsten Probleme anzusprechen, und sie damit zu kontrastieren, was ich Jacques Derridas häretische „Konzeptualisierung“ der Entscheidung nennen würde. Es wird gezeigt, dass diese häretische Thematisierung von Derrida nicht nur und einfach mit dem traditionellen aristotelischen Begriff bricht, sondern vielmehr auch zu Recht einige seiner wichtigsten Züge auf solcher Weise schärft, dass von diesem radikalisierten Standpunkt die Behandlung von Aristoteles als die Annullierung der Entscheidung zum Vorschein kommt. Es wird zudem impliziert, wie Derridas häretische Auffassung die Erneuerung der Ethik und Politik mit sich bringt.

  17. STUDY OF THE Al/GRAPHITE INTERFACE

    Institute of Scientific and Technical Information of China (English)

    LU HUA(陆华); SHEN DIAN-HONG(沈电洪); DENG XIN-FA(邓新发); XUE QI-KUN(薛其坤); N.FROUMIN; M.POLAK

    2001-01-01

    Thin Al films with a thickness of 20-30nm were prepared by ltra-high vacuum deposition of Al onto a graphite surface arallel to a (0001) basal plane. The samples were annealed up to 1070K. X-ray photoelectron spectroscopy analysis has shown that for temperatures just higher than 770K, a little carbide occurs in the Al film and only an AI-C phase is present at the Al/graphite interface. After nnealing at 970K, the Al4C3 phase can be observed, and the binding energy of the Al2p electrons increases continuously from 72.7 to 74.2eV with increasing temperature up to 1070K. Auger electron spectroscopy depth profiles are measured to investigate the phases existing in the Al film as well as at the Al/graphite interface. It is found that the Al4C3 hase at the interface is the final product of a series of Al carbides from the interfacial reaction between Al and graphite.

  18. AlON粉体的合成

    Institute of Scientific and Technical Information of China (English)

    赵小军; 茹红强; 张宁; 孙有政

    2009-01-01

    以α-Al2O3和AlN为原料,利用高温固相反应在氮气气氛下常压合成了AlON粉体。研究了成分配比、合成温度、保温时间对合成AlON粉体含量的影响,并通过热分析测试了合成过程热流和质量的变化。结果表明,当原料Al2O3和AlN的质量比为81:18、合成工艺为1750℃,2h时,得到AlON相的含量达到95%以上。

  19. Preparation and Characterization of Highly Flexible Al2O3/Al/Al2O3 Hybrid Composite

    Directory of Open Access Journals (Sweden)

    Zhijiang Wang

    2015-01-01

    Full Text Available The natural brittleness of oxide ceramics heavily inhibits their more extensive applications. In present research, a highly flexible Al2O3/Al/Al2O3 hybrid composite was fabricated by employing plasma electrolysis oxidation to in situ grow alumina layers on Al foil, in which an outside layer of nanostructured polycrystalline oxide ceramic was composed of nanosized grains with the size of around 17 nm. Due to shear band formation, nanosized circle bubbles prolonging the crack path, grain rotation, and deformation, the fabricated Al2O3/Al/Al2O3 hybrid composite contains no observable cracks even after being bent on a cylindrical bar with a curvature of 1.5 mm. The composite exhibits alumina stiffness at the elastic stage and aluminum ductility during plastic deformation, which provides high flexibility with the well-integrated properties of the components. In a synergistic interaction, the alumina on the outside exhibited a strain of 0.33% at room temperature, which was higher than optimum value of 0.25% presented by reported most flexible oxide ceramics. With the unique characteristics and properties, the Al2O3/Al/Al2O3 composite demonstrates a great potential for various engineering applications.

  20. MARTENSITIC TRANSFORMATION AND THERMAL STABILITY IN Cu-Al-Co AND Cu-Al-Zr ALLOYS

    Institute of Scientific and Technical Information of China (English)

    Y. Q. Ma; C.B. Jiang; H.B. Xu

    2003-01-01

    Cu-Al-Co and Cu-Al-Zr alloys were explored with Co or Zr additions in Cu-Al alloys for high temperature shape memory alloys. Samples were quenched after homogenized at 850℃ for 48h. It was found that both Cu-Al-Co and Cu-Al-Zr show AlCu3 martensitic phase at room temperature and exhibit martensitic transformation temperatures higher than 200℃, showing the potentials for developing as high temperature shape memory alloys. Thermal cycles were performed by DSC instrument on both Cu-Al-Co and Cu-Al-Zr alloys. The results show that Cu-Al-Co loses its martensitic transformation after five thermal cycles, and Cu-Al-Zr exhibits no martensitic transformation in the second thermal cycle.

  1. Friction Stir Welding of Al 5052 with Al 6061 Alloys

    Directory of Open Access Journals (Sweden)

    N. T. Kumbhar

    2012-01-01

    Full Text Available Friction stir welding (FSW, a solid-state joining technique, is being extensively used in similar as well as dissimilar joining of Al, Mg, Cu, Ti, and their alloys. In the present study, friction stir welding of two aluminium alloys—AA6061 and AA5052—was carried out at various combinations of tool rotation speeds and tool traverse speeds. The transverse cross-section of the weld was used for optical as well as electron microscopy observations. The microstructural studies were used to get an indication of the extent of material mixing both at the macro- and microscales. It was observed that, at the interface region, both materials exhibited similar texture despite the nonrigorous mixing of the materials in the nugget. The extent of interdiffusion of alloying elements at the interface was studied using electron probe microanalysis. The tensile testing evaluation of these specimens showed good mechanical properties. The interdiffusion of alloying elements and development of similar orientations in the nugget could have contributed to the better tensile properties of the friction-stir-welded AA5052-AA6061 specimens.

  2. Efficiency droop in high-Al-content AlGaN/AlGaN quantum wells

    Energy Technology Data Exchange (ETDEWEB)

    Tamulaitis, G.; Mickevicius, J.; Kazlauskas, K.; Zukauskas, A. [Institute of Applied Research and Department of Semiconductor Physics, Vilnius University, Sauletekio 9-III, 10222 Vilnius (Lithuania); Shur, M.S. [Department of ECE and CIE, Rensselaer Polytechnic Institute, 110 Eighth Street, Troy, NY 12180 (United States); Yang, J.; Gaska, R. [Sensor Electronic Technology Inc., 1195 Atlas Road, Columbia, SC 29209 (United States)

    2011-07-15

    Excitation power density dependence of photoluminescence (PL) efficiency is studied in the temperature range from 8 to 300 K for AlGaN multiple quantum well structures containing quantum wells of different width. PL efficiency droop is observed and dependence of the droop effect on the well width and lattice temperature is discussed. Photoluminescence band shape reveals strong carrier heating. It is shown that the heating effect has a substantial influence on the photoluminescence efficiency droop, especially at low lattice temperatures. Fitting of the temperature dependence of the PL band width with that obtained by the Monte Carlo simulation of carrier (exciton) hopping via localized states shows that (i) the potential fluctuations can be fairly accurately described using a double-scaled potential profile model, (ii) the localization becomes stronger in narrower quantum wells. (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  3. Atomic structure and oxygen deficiency of the ultrathin aluminium oxide barrier in Al/AlOx/Al Josephson junctions

    OpenAIRE

    Lunjie Zeng; Dung Trung Tran; Cheuk-Wai Tai; Gunnar Svensson; Eva Olsson

    2016-01-01

    Al/AlOx/Al Josephson junctions are the building blocks of a wide range of superconducting quantum devices that are key elements for quantum computers, extremely sensitive magnetometers and radiation detectors. The properties of the junctions and the superconducting quantum devices are determined by the atomic structure of the tunnel barrier. The nanoscale dimension and disordered nature of the barrier oxide have been challenges for the direct experimental investigation of the atomic structure...

  4. Al-Si/Al2O3 in situ composite prepared by displacement reaction of CuO/Al system

    Directory of Open Access Journals (Sweden)

    Zhang Jing

    2010-02-01

    Full Text Available Al2O3 particle-reinforced ZL109 composite was prepared by in situ reaction between CuO and Al. The microstructure was observed by means of OM, SEM and TEM. The Al2O3 particles in sub-micron sizes distribute uniformly in the matrix, and the Cu displaced from the in situ reaction forms net-like alloy phases with other alloy elements. The hardness and the tensile strength of the composites at room temperature have a slight increase as compared to that of the matrix. However, the tensile strength at 350 ℃ has reached 90.23 MPa, or 16.92 MPa higher than that of the matrix. The mechanism of the reaction in the CuO/Al system was studied by using of differential scanning calorimetry(DSC and thermodynamic calculation. The reaction between CuO and Al involves two steps. First, CuO reacts with Al to form Cu2O and Al2O3 at the melting temperature of the matrix alloy, and second, Cu2O reacts with Al to form Cu and Al2O3 at a higher temperature. At ZL109 casting temperature of 750–780 ℃, the second step can also take place because of the effect of exothermic reaction of the first step.

  5. Entrevista al narrador Tommaso Pincio

    Directory of Open Access Journals (Sweden)

    Franco Zangrilli

    2016-07-01

    Full Text Available El autor Tommaso Pincio, seudónimo di Marco Colapietro (Roma, 1963, es sin lugar a dudas uno de los narradores de mayor proyección en el panorama literario de los últimos tiempos. Iniciada su carrera en 1999 con M., ha publicado títulos como Lo spazio sfinito (2000 y Un amore dell'altro mondo (2002, en el que narra la vida de Kurt Cobain, líder del grupo Nirvana, a través de la visión de un amigo imaginario. A estas dos novelas siguieron La ragazza che non era lei (2005, Gli alieni (2006 o Cinacittà. Memorie del mio delitto efferato (2008, ambientada en una Roma colonizada por los chinos y abandonada por los mismos romanos a causa de problemas medioambientales. Títulos como L'hotel a zero stelle (2011, un ensayo autobiográfico en el que plantea diálogos ficticios con algunos de los grandes nombres de la literatura o la más reciente Panorama (2015, le han hecho valerse un hueco provilegiado entre los nuevos narradores surgidos en estas primeras décadas de siglo. Justamente la publicación de esta última novela, Panorama, ha servido de excusa al profesor Franco Zangrilli, gran conocedor de su obra, a plantearle algunas preguntas sobre temas clave de su producción.

  6. Fabrication of TiAl3 coating on TiAl-based alloy by Al electrodeposition from dimethylsulfone bath and subsequent annealing

    OpenAIRE

    Miyake, Masao; Tajikara, Seiya; Hirato, Tetsuji

    2011-01-01

    TiAl3 coating was formed on TiAl alloy by Al electrodeposition from a dimethylsulfone (DMSO2) bath and subsequent annealing. Before the Al electrodeposition, anodic dissolution of TiAl substrate in the DMSO2 bath was conducted to remove the surface oxide layer of the TiAl substrate. By performing the Al electrodeposition immediately after the anodic dissolution, uniform Al films adherent to the TiAl substrate could be obtained. Annealing at 650–1000 °C yielded a single TiAl3 layer or two laye...

  7. Fabrication of AlN-TiC/Al composites by gas injection processing

    Institute of Scientific and Technical Information of China (English)

    YU Huashun; CHEN Hongmei; MA Rendian; MIN Guanghui

    2006-01-01

    The fabrication of AlN-TiC/Al composites by carbon-and nitrogen-containing gas injection into Al-Mg-Ti melts was studied. It was shown that AlN and TiC particles could be formed by the in situ reaction of mixture gas (N2+C2H2+NH3) with Al-Mg-Ti melts. The condition for the formation of AlN was that the treatment temperature must be higher than 1373 K, and the amounts of AlN and TiC increased with the increase of the treatment temperature and the gas injection time.It was considered that AlN was formed by the direct reaction of Al with nitrogen-containing gas at the interface of the gas bubble and the melt. However, the mechanism of TiC formation is a combination mechanism of solution-precipitation and solid-liquid reaction.

  8. Orientation relationship of eutectoid FeAl and FeAl2

    Science.gov (United States)

    Scherf, A.; Kauffmann, A.; Kauffmann-Weiss, S.; Scherer, T.; Li, X.; Stein, F.; Heilmaier, M.

    2016-01-01

    Fe–Al alloys in the aluminium range of 55–65 at.% exhibit a lamellar microstructure of B2-ordered FeAl and triclinic FeAl2, which is caused by a eutectoid decomposition of the high-temperature Fe5Al8 phase, the so-called ∊ phase. The orientation relationship of FeAl and FeAl2 has previously been studied by Bastin et al. [J. Cryst. Growth (1978 ▸), 43, 745] and Hirata et al. [Philos. Mag. Lett. (2008 ▸), 88, 491]. Since both results are based on different crystallographic data regarding FeAl2, the data are re-evaluated with respect to a recent re-determination of the FeAl2 phase provided by Chumak et al. [Acta Cryst. (2010 ▸), C66, i87]. It is found that both orientation relationships match subsequent to a rotation operation of 180° about a 〈112〉 crystallographic axis of FeAl or by applying the inversion symmetry of the FeAl2 crystal structure as suggested by the Chumak data set. Experimental evidence for the validity of the previously determined orientation relationships was found in as-cast fully lamellar material (random texture) as well as directionally solidified material (∼〈110〉FeAl || solidification direction) by means of orientation imaging microscopy and global texture measurements. In addition, a preferential interface between FeAl and FeAl2 was identified by means of trace analyses using cross sectioning with a focused ion beam. On the basis of these habit planes the orientation relationship between the two phases can be described by (01)FeAl || (114) and [111]FeAl || [10]. There is no evidence for twinning within FeAl lamellae or alternating orientations of FeAl lamellae. Based on the determined orientation and interface data, an atomistic model of the structure relationship of Fe5Al8, FeAl and FeAl2 in the vicinity of the eutectoid decomposition is derived. This model is analysed with respect to the strain which has to be accommodated at the interface of FeAl and FeAl2. PMID:27047304

  9. Electron channelling enhanced microanalysis on Ni-Al-Mn and Al-Mn-Si

    International Nuclear Information System (INIS)

    Atom location by channelling enhanced microanalysis (ALCHEMI) was performed for Ni-Al-Mn compounds and Al-Mn-Si quasicrystals. For Ni75Al25-xMnx (x=5,9) with the L12-type structure, an occupation fraction of Mn atoms at the Ni site was quantitatively determined using planar channelling conditions. The occupation fraction increases with the Mn concentration or by quenching the compound from high temperature. In quasicrystals of Al74Mn20Si6 and Al68Mn20Ru8Si4, axial channelling conditions were used to locate Si and Ru, respectively. It was shown that Si atoms occupy the Al site in Al74Mn20Si6 whereas Ru atoms occupy the site different from that of Al in Al68Mn20Ru8Si4. (author)

  10. A New Phase in ALS Research.

    Science.gov (United States)

    Chong, P Andrew; Forman-Kay, Julie D

    2016-09-01

    In this issue of Structure, Conicella et al. (2016) present evidence that the low complexity C-terminal region of TDP-43 undergoes liquid-liquid phase separation. ALS-associated mutations alter this phase separation process, providing a possible mechanism for the pathology caused by these TDP-43 mutations. The work is strongly supportive of toxic loss of RNA processing function in ALS. PMID:27602988

  11. The wobbler mouse, an ALS animal model

    OpenAIRE

    Moser, Jakob Maximilian; Bigini, Paolo; Schmitt-John, Thomas

    2013-01-01

    This review article is focused on the research progress made utilizing the wobbler mouse as animal model for human motor neuron diseases, especially the amyotrophic lateral sclerosis (ALS). The wobbler mouse develops progressive degeneration of upper and lower motor neurons and shows striking similarities to ALS. The cellular effects of the wobbler mutation, cellular transport defects, neurofilament aggregation, neuronal hyperexcitability and neuroinflammation closely resemble human ALS. Now,...

  12. Casting fabrication of in situ Al3Ti-Al composites and their wear behaviors

    Institute of Scientific and Technical Information of China (English)

    Chen Tijun; Li Jian; Hao Yuan

    2009-01-01

    The Al3li intermetallic reinforced pure Al, Al-13Si and Al-17Cu matrix composites were prepared by casting method. Their microstructures and dry sliding wear behaviors at room temperature and 100℃ were particularly investigated. The results indicated that the Al3Ti phases in these composites were all in flaky form. But the aspect ratio of the Al3Ti platelets decreased with the increase of Ti content in the pure AI, Al-Cu and Al-Si matrix composites, in order of effectiveness. The effect of Si on the Al3Ti morphology seemed to be greater than that of Cu. The distributions of the Al3Ti platelets were different in the different matrix composites, leading to different grain refining effects. Except for the sub-wear regime of adhesive wear, the plastic deformation induced wear was a dominant wear mechanism for all of the composites at room temperature and 100℃. Increasing the testing temperature, decreasing the Al3Ti content or the hardness of materials could enhance these two wear mechanisms, and thus increase the wear rate. The Al-Cu matrix composite had the best wear resistance, while the pure Al matrix composite showed the worst for the same Ti content. These differences or changes were attributed to the differences in materials' hardness or the strengthening effects of the Al3Ti platelets.

  13. Groente- en fruitafvallen als veevoer : inventarisatie

    NARCIS (Netherlands)

    Vries, de A.

    1982-01-01

    Een onderzoek wat betreft hoeveelheden, bewaring, samenstelling, verteerbaarheid en eventueel aanwezige ongewenste stoffen van de bij- en afvalprodukten van groenten en fruit als veevoer voor herkauwers

  14. Genetics of Familial and Sporadic ALS

    Science.gov (United States)

    2016-03-21

    Amyotrophic Lateral Sclerosis (ALS); Familial Amyotrophic Lateral Sclerosis; Amyotrophic Lateral Sclerosis With Frontotemporal Dementia; Lou Gehrig's Disease; Motor Neuron Disease; Primary Lateral Sclerosis

  15. Growth of CdTe: Al films

    International Nuclear Information System (INIS)

    CdTe: AI films were grown by the close space vapor transport technique combined with free evaporation (CSVT-FE). The Aluminum (Al) evaporation was made by two kinds of sources: one made of graphite and the other of tantalum. The films were deposited on glass substrates. The Al source temperature was varied maintaining the CdTe source temperature fixed as well as the substrate temperature. The films were characterized by x-ray energy dispersive analysis (EDAX), x-ray diffraction and optical transmission. The results showed for the films grown with the graphite source for Al evaporation, the Al did not incorporate in the CdTe matrix, at least to the level of EDAX sensitivity; they maintained the same crystal structure and band gap. For the samples grown with the tantalum source, we were able to incorporate the Al. The x-ray diffraction patterns show that the films have a crystal structure that depends on Al concentration. They were cubic up to 2.16 at. % Al concentration; for 19.65 at. % we found a mixed phase; for Al concentration higher than 21 at. % the films were amorphous. For samples with cubic structure it was found that the lattice parameter decreases and the band gap increases with Al concentration. (Author)

  16. Influence of Al Composition on the Microstructure of B Alloyed Ni3Al Synthesized under Compression

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    It was shown by TEM and X-ray analysis that Ni3Al is the mainphase of the intermetallic synthesized under compression from the powder mixture of Ni with Al alloyed by B. The Ni3B is a secondary phase. The value of the lattice parameter of the intermetallic Ni3Al with and without B increases when the concentration of Al increases. The increase in Al concentration from 23.5 to 25.0 in the initial powder mixture leads to decreasing the solubility of B in the Ni3Al phase.

  17. 关于w-al-CL空间%On w-al-CL Spaces

    Institute of Scientific and Technical Information of China (English)

    林丽琼; 张云南

    2011-01-01

    给出w-al-CL空间的定义,比较几种CL性的关系,讨论w-al-CL空间的c0和与l1和的稳定性,并讨论C(K,X)空间的w-al-CL性.%Gives the definition of w-al-CL spaces, compare the relationship of some properties of CL, discusses the stability of c0 -sums and l1 -sums of w-al-CL spaces, and discusses the property of w-al-CL of C(K,X) spaces.

  18. Response to Signorovitch et al.

    Science.gov (United States)

    Flot, Jean-François; Debortoli, Nicolas; Hallet, Bernard; Van Doninck, Karine

    2016-08-22

    Signorovitch et al.[1] comment that an Oenothera-like meiosis [2] could produce a pattern similar to what we observed in our study of natural isolates of the bdelloid rotifer Adineta vaga, which we attributed to horizontal gene transfers (HGTs) [3]. Indeed, our HGT hypothesis appears at first sight difficult to conciliate with their observation of a congruent pattern of allele sharing at four large loci possibly located on different chromosomes [4]. However, one might imagine conditions under which massive horizontal gene transfer between bdelloid individuals could produce such a pattern, notably if the individuals involved had previously lost most of their heterozygosity because of their exposure to frequent desiccation (which produces DNA double-strand breaks [5]). In the published A. vaga genome the loss of heterozygosity due to large-scale gene conversion events or break-induced replication covers only about 10% of the genome [6], but this percentage may be much higher in environmental isolates that often experience dessication. Besides, if an Oenothera-like mode of meiosis occurs in bdelloids frequently enough to be detected in a single sampling of 29 individuals (as in [4]), one would expect males and meiosis to be observed at least occasionally, and instances of congruent allele sharing across loci should turn up frequently in genetic surveys. This was not the case in [3]: among the 82 A. vaga individuals sequenced for four nuclear markers, no trio of individuals presented congruent patterns of shared sequences at different loci. For these reasons, and in the absence of any direct evidence for an Oenothera-like meiosis in bdelloids, we still consider inter-bdelloid HGTs a more parsimonious explanation for our results. PMID:27554651

  19. La familia, pieza clave de la educación personalizada

    OpenAIRE

    GdI Educación Personalizada en la Era Digital, EPEDIG

    2015-01-01

    El 23 de Marzo de 2015 tuvimos el placer de contar en nuestro seminario SIEP con María Bellmunt Borrás, Presidenta de la asociación catalana "Reconeixement i la Regulació del Homeschooling", que reúne a más de cien familias, cuyo objetivo principal es el diálogo político y administrativo para conseguir la normalización y regulación de la escolariza-ción en familia.

  20. Inspección de piezas 3D: revisión de la literatura

    Directory of Open Access Journals (Sweden)

    Andrés Eleázar Jaramillo

    2010-04-01

    Full Text Available A survey of inspection systems using range images is presented; the review focus especially on papers published from 2000 to 2006. The inspection systems are classified according to the techniques used in the acquisition stage. The specific applications of inspection considered in the mentioned works are described, as well as the most outstanding characteristics of systems developed to date. Tendencies in such developments are identified from these characteristics, such as the search for increased CAD-model based flexibility and the preferential use of active triangulation systems (especially projecting structured light as a light plane and fringes instead of passive systems. The problem of inspecting deformable pieces is then presented, representing an open topic for considering developing future systems. The more relevant works related to this topic are also discussed.

  1. Conservacion de piezas anatomicas en seco mediante el metodo de prives

    Directory of Open Access Journals (Sweden)

    Flavio Correa Alarcón. Profesor Consultante .

    2005-05-01

    Full Text Available [...Los medios de enseñanza son apropiados para reducir el camino hacia el objetivo o enriquecerlo con relación con su contenido. De acuerdo con el rápido y continuo desarrollo de la revolución científico técnica de nuestro tiempo, el proceso docente educativo requiere de métodos, procedimientos y medios de enseñanza capaces de absorber el mayor número posible de conocimientos para hacerlo llegar a los estudiantes.-La calidad de un medio es dado por el mayor número de receptores que estimula. Demostrar y observar los objetos originales en la clase, tiene como ventaja en que los alumnos pueden dedicarle toda su atención, sin embargo, tienen el inconveniente de no poderlos conservar u forma original una vez preparados se deterioran fácilmente, pierden sus características morfológicas y pueden dar una información tergiversada a los alumnos....

  2. Atomic structure and oxygen deficiency of the ultrathin aluminium oxide barrier in Al/AlOx/Al Josephson junctions.

    Science.gov (United States)

    Zeng, Lunjie; Tran, Dung Trung; Tai, Cheuk-Wai; Svensson, Gunnar; Olsson, Eva

    2016-01-01

    Al/AlOx/Al Josephson junctions are the building blocks of a wide range of superconducting quantum devices that are key elements for quantum computers, extremely sensitive magnetometers and radiation detectors. The properties of the junctions and the superconducting quantum devices are determined by the atomic structure of the tunnel barrier. The nanoscale dimension and disordered nature of the barrier oxide have been challenges for the direct experimental investigation of the atomic structure of the tunnel barrier. Here we show that the miniaturized dimension of the barrier and the interfacial interaction between crystalline Al and amorphous AlOx give rise to oxygen deficiency at the metal/oxide interfaces. In the interior of the barrier, the oxide resembles the atomic structure of bulk aluminium oxide. Atomic defects such as oxygen vacancies at the interfaces can be the origin of the two-level systems and contribute to decoherence and noise in superconducting quantum circuits. PMID:27403611

  3. Atomic structure and oxygen deficiency of the ultrathin aluminium oxide barrier in Al/AlOx/Al Josephson junctions

    Science.gov (United States)

    Zeng, Lunjie; Tran, Dung Trung; Tai, Cheuk-Wai; Svensson, Gunnar; Olsson, Eva

    2016-07-01

    Al/AlOx/Al Josephson junctions are the building blocks of a wide range of superconducting quantum devices that are key elements for quantum computers, extremely sensitive magnetometers and radiation detectors. The properties of the junctions and the superconducting quantum devices are determined by the atomic structure of the tunnel barrier. The nanoscale dimension and disordered nature of the barrier oxide have been challenges for the direct experimental investigation of the atomic structure of the tunnel barrier. Here we show that the miniaturized dimension of the barrier and the interfacial interaction between crystalline Al and amorphous AlOx give rise to oxygen deficiency at the metal/oxide interfaces. In the interior of the barrier, the oxide resembles the atomic structure of bulk aluminium oxide. Atomic defects such as oxygen vacancies at the interfaces can be the origin of the two-level systems and contribute to decoherence and noise in superconducting quantum circuits.

  4. Kritik al-Ghazali terhadap Kekekalan Alam

    Directory of Open Access Journals (Sweden)

    Sahidi Mustafa

    2015-12-01

    Full Text Available The concept of the creation of universe offered by Neo-Platonism philosopher such as al-Kindi, al-Farabi, and Ibnu Sina are philosophical concept existed and came as an early moment of development of Islamic philosophy interrelated to God, ultimately about his Existence and Characteristics. One of the topics is how God created the universe. According to al-Farabi and Ibnu Sina, God created this universe by way of emanation in order to prevent Himself from the new attitudes. Consequently, universe has eternal feature (qadim as God as well, in the case of everything overflowed from qadim is also qadim. Al-Ghazali refuted this theory because it contradicted with al Qur’an’s thought which clearly explained that God created the entire universe. The universe should not qadim and it means that God existed in the first, and then created universe later as we know today. On the contrary, in the view of Muslim philosopher, the universe should be qadim because God created it from all eternity. For them, it is impossible that God existed by Himself without any creation before. God, according to them is impossible to be changed, so that is impossible as well if God changed from did not create yet before and then creates. Al-Ghazali persistently opposed the concept of eternity. Al Ghazali saw if this universe is qadim so it is impossible that universe created by God. The concept of qadim will led to the conclusion that universe born by itself, it was not created by God. This critique has been written by al-Ghazali in Tahafut al-Falasifah. This paper will present the concept of eternity which was discussed by al-Farabi and Ibn Sina and al Ghazali’s critique toward it as well.

  5. Untersuchung der Nitridierung V/Al-intermetallischer Phasen

    OpenAIRE

    Lewalter, Hartmut Berthold

    2004-01-01

    Schichten V/Al-Intermetallischer Phasen und Schichten aus V(Al) (Schichtdicken 150- 300 nm) wurden durch Interdiffusion von V/Al- und V5Al8/V-Mehrfachschichten bei 400-800°C im Vakuum bei 3 x 10-8 mbar hergestellt. Des Weiteren wurden V5Al8-Schichten durch Sputtern einer V5Al8-Legierung erzeugt. Die Gesamtstöchiometrie der Schichten lag zwischen Al0,86V0,14 und Al0,19V0,81. Als Substrat dienten einkristalline (012) Saphirwafer. Die V/Al-Intermetallischen Phasen und V(Al) wurden im RTP-System ...

  6. Influence of AlN thickness on AlGaN epilayer grown by MOCVD

    Science.gov (United States)

    Jayasakthi, M.; Juillaguet, S.; Peyre, H.; Konczewicz, L.; Baskar, K.; Contreras, S.

    2016-10-01

    AlGaN/AlN layers were grown by metalorganic chemical vapor deposition (MOCVD) on sapphire substrates. The AlN buffer thickness was varied from 400 nm to 800 nm. The AlGaN layer thickness was 1000 nm. The crystalline quality, thickness and composition of AlGaN were determined using high resolution X-ray diffraction (HRXRD). The threading dislocation density (TDD) was found to decrease with increase of AlN layer thickness. Reciprocal space mapping (RSM) was used to estimate the strain and relaxation between AlGaN and AlN. The optical properties of AlGaN layers were investigated by temperature dependent photoluminescence (PL). PL intensities of AlGaN layers increases with increasing the AlN thickness. The surface morphology of AlGaN was studied by atomic force microscopy (AFM). Root mean square (RMS) roughness values were found to be decreased while increase of AlN thickness.

  7. Avance al estudio radiológico del armamento de la necrópolis ibérica del Cabecico del Tesoro (Verdolay, Murcia. I. - Las Falcatas

    Directory of Open Access Journals (Sweden)

    García Cano, José Miguel

    2006-12-01

    Full Text Available

    We present a new study of the falcata swords decorated with silver inlay from the Iberian Iron Age cemetery at Cabecico del Tesoro (Murcia. Already known pieces are re-studied, while we also present new examples of previously unknown decorations, hidden under the corrosion layers but visible under radiographic examination.



    Se presenta un nuevo estudio de las falcatas decoradas con damasquinados en plata de la necrópolis ibérica del Cabecico del Tesoro (Murcia, Se reestudian piezas conocidas y se presentan nuevos casos de decoraciones previamente ocultas bajo la corrosión pero visibles en un examen radiológico efectuado sobre las piezas.

  8. The theory of the moon in the al-Zij al-Kamil fi-l-taalim of Ibn al-Ha'im

    OpenAIRE

    Puig i Tàrrech, Roser

    2000-01-01

    Al the beginning of Ihe thirteenth cenrury (60tH I 1204-1205) Abli Muhammad Abd al-Haqq al-Ghafiqi al-lshbiIi known as Ibn al-Ha'im composed his work entitled al-Zi] al-Kamil fi-l-Taalim in honour of the Caliph Abu Abd Allah Muhammad al-Nasir (who reigned from 1199- 1213). All we know of lbn al-Ha'im's live is that he came from Seville and that he appears to have worked in North Africa.

  9. Geluk als onderwerp van wetenschappelijk onderzoek

    NARCIS (Netherlands)

    R. Veenhoven (Ruut)

    1970-01-01

    textabstractAbstract in Dutch: Geluk wordt gedefinieerd als overwegende tevredenheid met het leven als geheel. Dit artikel geeft een overzicht van het onderzoek naar dat verschijnsel. Geluk blijkt deels afhankelijk van persoonlijke eigenschappen. Zo blijkt ondermeer dat gelukkige mensen over het alg

  10. 75 FR 62858 - United States, et al.

    Science.gov (United States)

    2010-10-13

    ... Antitrust Division United States, et al. v. American Express Company, et al.; Proposed Final Judgment and... been filed with the United States District Court for the Eastern District of New York in United States..., 2010, the United States and seven States filed a Complaint alleging that certain rules, policies,...

  11. Als je vrienden hebt dan win je

    NARCIS (Netherlands)

    Effing, R. (Robin); Huibers, T. (Theo); Krosse, de L. (Luc)

    2010-01-01

    Als je wint, heb je vrienden’ is een Nederlandse klassieker van Herman Brood en Henny Vrienten. Hiermee werd de gevoelige snaar bloot gelegd dat pas als je hebt gewonnen je vrienden hebt. Rijen dik, echte vrienden. In de politiek werkt het andersom; je moet vrienden (stemmen) hebben, ve

  12. Diana Al-Hadid: Identity and Heritage

    Science.gov (United States)

    Jungerberg, Tom; Smith, Anna; Borsh, Colleen

    2012-01-01

    Diana Al-Hadid's sculptures reflect the many locations, cultures, histories, and mythologies that have shaped her as an artist. In large-scale works which have the appearance of architectural ruins, Al-Hadid employs imagery drawn from many diverse interests including science and technology, history, and literature. She also incorporates images and…

  13. Kus on al-Zarqawi? / Aadu Hiietamm

    Index Scriptorium Estoniae

    Hiietamm, Aadu, 1954-

    2005-01-01

    Suurbritannia nädalalehe Sunday Times andmetel on Iraagi tagaotsituim mässaja, terrorivõrgustiku al Qaeda liitlane Abu-Musab al-Zarqawi pärast USA raketirünnakus haavatasaamist riigist põgenenud

  14. Al-Farabi dan Filsafat Kenabian

    Directory of Open Access Journals (Sweden)

    Qosim Nursheha Dzulhadi

    2014-03-01

    Full Text Available Artikel ini mengulas pemikiran al-Farabi tentang konsep kenabian dalam Islam. Masalah berawal dari adanya pemikiran yang menolak konsep kenabian pada umumnya dan kenabian Nabi Muhammad SAW khususnya. Sebagaimana yang dilontarkan oleh Muhammad Ahmad ibn al-Ruwandi. Ia mengatakan bahwa nabi sebenarnya tidak diperlukan manusia karena Tuhan telah mengaruniakan akal kepada manusia tanpa terkecuali. Dengan akal ini, manusia dapat mengetahui Tuhan beserta segala nikmat Nya dan dapat pula mengetahui perbuatan baik dan buruk, menerima suruhan dan larangan-Nya. Dengan demikian, nabi dengan segala fungsinya tidak diperlukan lagi. Bahkan, kitab suci pun tidak berguna untuk dibaca. Lebih berguna membaca buku filsafat Epicurus, Plato, Aristoteles, dan buku astronomi, logika, serta obat-obatan. Hal ini tentunya bertolak belakang dengan yang diajarkan dalam Islam. Beriman kepada nabi nabi merupakan hal inti dalam ajaran agama ini. Atas dasar itu al-Farabi bereaksi keras. Baginya, pandangan Ibn al-Ruwandi di atas tidak dapat dibenarkan, khususnya dari sisi akidah Islam. Sebagai al-Mu‘allim al-Tsani (Guru Kedua, karena prestasinya dalam menjelaskan dan mengulas-ulang filsafat Aristoteles, al-Farabi mengkritik secara sistematik pandangan menyimpang al-Ruwandi di atas.

  15. The role of inclusions in ALS pathogenesis

    NARCIS (Netherlands)

    V. van Dis (Vera)

    2012-01-01

    textabstractAmyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease that primarily afflicts motor neurons, leading to paralysis and death within 3 to 5 years after diagnosis. Genetic studies have uncovered multiple genetic defects causing familial forms of ALS and mutations oc

  16. Data supporting Al-Abed et al., Environ. Sci.: Nano, 2016,

    Data.gov (United States)

    U.S. Environmental Protection Agency — Data files representing each of the Figures and Tables published in Al-Abed et al., Environ. Sci.: Nano, 2016, 3, 593. The data file names identify the Figure or...

  17. Effect of Al coating conditions on laser weldability of Al coated steel sheet

    Institute of Scientific and Technical Information of China (English)

    Jung-Han LEE; Jong-Do KIM; Jin-Seok OH; Seo-Jeong PARK

    2009-01-01

    Al coated steel sheets with excellent heat resistance, thermal reflection, and corrosion resistance are widely used in various applications. The laser weldability of the Al coated steel sheet for full penetration welding was reported. The phenomenon caused by intermixed aluminum and behavior of aluminum in the weld were investigated. Al coated steel sheets that have various thickness and coating mass were prepared for laser welding. The effects of parameters such as welding conditions and Al coating conditions were investigated. Al content mixed in the weld after laser welding was evaluated, and then a correlation between the mixed Al and mechanical properties was investigated. The results show that the Al-rich zones which have Fe-Al intermetallic compounds are found in the weld. The intermetallic compounds cause the decreased strength of the weld.

  18. Kinetic Monte Carlo of transport processes in Al/AlOx/Au-layers: Impact of defects

    Directory of Open Access Journals (Sweden)

    Benedikt Weiler

    2016-09-01

    Full Text Available Ultrathin films of alumina were investigated by a compact kMC-model. Experimental jV-curves from Al/AlOx/Au-junctions with plasma- and thermal-grown AlOx were fitted by simulated ones. We found dominant defects at 2.3-2.5 eV below CBM for AlOx with an effective mass mox∗=0.35 m0 and a barrier EB,Al/AlOx≈2.8 eV in agreement with literature. The parameterization is extended to varying defect levels, defect densities, injection barriers, effective masses and the thickness of AlOx. Thus, dominant charge transport processes and implications on the relevance of defects are derived and AlOx parameters are specified which are detrimental for the operation of devices.

  19. Konsepsi Ibnu Jarir Al-Tabari Tentang Al-Qur’an, Tafsir Dan Ta’wil

    Directory of Open Access Journals (Sweden)

    A.M Ismatulloh

    2012-12-01

    Full Text Available The objective of this research is to describe the concept of Ibnu Jarir al-Tabari about al-Qur’an, tafsir and ta’wil. Ibn Jarir al-Tabari is an outstanding expert in the classic Islamic tradition. His knowledge in hadits, fiqh, lughah, history, and tafseer is unquestionable. This study uses an analytical descriptive design. The findings show that: Firstly, in defining al-Qur’an, al-Tabari focused on the al-Qur’an as an Arabic language text, not in other language. Secondly, al-Qur’an is written in sab’ah ahruf. It means that there are 7 different kinds of language with the same meaning. Thirdly, al-Qur’an comes from seven heaven’s door. Fourthly, there is no different word between tafseer and ta’wil. They have same meaning. These concepts are different to other concepts proposed by other ulama.

  20. Thermoluminescence properties of AlN ceramics

    DEFF Research Database (Denmark)

    Trinkler, L.; Christensen, P.; Agersnap Larsen, N.;

    1998-01-01

    The paper describes thermoluminescence (TL) properties of AlN:Y2O3 ceramics irradiated with ionising radiation. A high TL sensitivity of AlN:Y2O3 ceramics to radiation encouraged a study of the AlN ceramics for application as a dosimetric material. The paper presents experimental data on: glow...... curve, emission spectrum, dose response, energy dependence, influence of heating rate and fading rate. The measured TL characteristics were compared with those of well-known, widely used TLDs, i.e. LiF:Mg,Ti, LiF:Mg,Cu,P and Al2O3:C. It is concluded that AlN:Y2O3 ceramics showing a radiation sensitivity...

  1. High temperature creep behaviour of Al-rich Ti-Al alloys

    Energy Technology Data Exchange (ETDEWEB)

    Sturm, D; Heilmaier, M; Saage, H [Otto von Guericke University Magdeburg, Institute for Materials and Joining Technology, PO Box 4120, D-39016 Magdeburg (Germany); Aguilar, J; Schmitz, G J; Drevermann, A [ACCESS e.V., Intzestrasse 5, D-52072 Aachen (Germany); Palm, M; Stein, F; Engberding, N [Max-Planck-Institut fuer Eisenforschung GmbH, Max-Planck-Str. 1, D-40237 Duesseldorf (Germany); Kelm, K; Irsen, S, E-mail: daniel.sturm@ovgu.d [Stiftung caesar, Electron Microscopy, Ludwig-Erhard-Allee 2, D-53175 Bonn (Germany)

    2010-07-01

    Compared to Ti-rich {gamma}-TiAl-based alloys Al-rich Ti-Al alloys offer an additional reduction of in density and a better oxidation resistance which are both due to the increased Al content. Polycrystalline material was manufactured by centrifugal casting. Microstructural characterization was carried out employing light-optical, scanning and transmission electron microscopy and XRD analyses. The high temperature creep of two binary alloys, namely Al{sub 60}Ti{sub 40} and Al{sub 62}Ti{sub 38} was comparatively assessed with compression tests at constant true stress in a temperature range between 1173 and 1323 K in air. The alloys were tested in the cast condition (containing various amounts of the metastable phases Al{sub 5}Ti{sub 3} and h-Al{sub 2}Ti) and after annealing at 1223 K for 200 h which produced (thermodynamically stable) lamellar {gamma}-TiAl + r-Al{sub 2}Ti microstructures. In general, already the as-cast alloys exhibit a reasonable creep resistance at 1173 K. Compared with Al{sub 60}Ti{sub 40}, both, the as-cast and the annealed Al{sub 62}Ti{sub 38} alloy exhibit better creep resistance up to 1323 K which can be rationalized by the reduced lamella spacing. The assessment of creep tests conducted at identical stress levels and varying temperatures yielded apparent activation energies for creep of Q = 430 kJ/mol for the annealed Al{sub 60}Ti{sub 40} alloy and of Q = 383 kJ/mol for the annealed Al{sub 62}Ti{sub 38} material. The latter coincides well with that of Al diffusion in {gamma}-TiAl, whereas the former can be rationalized by the instability of the microstructure containing metastable phases.

  2. MOSQUE ARCHITECTURE AS A SUSTAINABLE BUILDING IN URBAN (Case Study: Al Markas Al Islamic Mosque Makassar)

    OpenAIRE

    Imriyanti Imriyanti

    2014-01-01

    Abstract Mosque Architecture is a part of Islamic architecture. Mosque should be fused with elements of nature because its function as a place to pray to God who created the universe. Al Markas Al Islamic Makassar mosque is used as a center of Islamic aspirations of the people and the government to accommodate all the activities of moslems in Makassar. Through this function, the provision of Al Markas Al Islamic mosque began from the desire of Islamic societies in Makassar, which want...

  3. Corrosion Studies of 2195 Al-Li Alloy and 2219 Al Alloy with Differing Surface Treatments

    Science.gov (United States)

    Danford, M. D.; Mendrek, M. J.

    1998-01-01

    Corrosion studies of 2195 Al-Li and 2219 Al alloys have been conducted using the scanning reference electrode technique (SRET) and the polarization resistance (PR) technique. The SRET was used to study corrosion mechanisms, while corrosion rate measurements were studied with the PR technique. Plates of Al203 blasted, soda blasted and conversion coated 2219 Al were coated with Deft primer and the corrosion rates studied with the EIS technique. Results from all of these studies are presented.

  4. Japanese version of the ALS-FTD-Questionnaire (ALS-FTD-Q-J).

    Science.gov (United States)

    Watanabe, Yasuhiro; Beeldman, Emma; Raaphorst, Joost; Izumi, Yuishin; Yoshino, Hiide; Masuda, Michihito; Atsuta, Naoki; Ito, Satoru; Adachi, Tadashi; Adachi, Yoshiki; Yokota, Osamu; Oda, Masaya; Hanashima, Ritsuko; Ogino, Mieko; Ichikawa, Hiroo; Hasegawa, Kazuko; Kimura, Hideki; Shimizu, Toshio; Aiba, Ikuko; Yabe, Hayato; Kanba, Makoto; Kusumi, Kimiyoshi; Aoki, Tetsuya; Hiroe, Yu; Watanabe, Hirohisa; Nishiyama, Kazutoshi; Nomoto, Masahiro; Sobue, Gen; Nakashima, Kenji

    2016-08-15

    Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) share common clinical, genetic and neuropathological features. Some ALS patients have behavioral/personality changes, which could result in significant obstacles in the care provided by family members and caregivers. An easy screening tool would contribute greatly to the evaluation of these symptoms. We translated the ALS-FTD-Questionnaire, developed in the Netherlands, into Japanese (ALS-FTD-Q-J) and examined the clinimetric properties (internal consistency, construct and clinical validity). Patients with ALS and/or behavioral variant FTD (bvFTD) were evaluated alongside healthy controls in this multicenter study. All ALS patients, regardless of bvFTD status, were further evaluated by the frontal behavioral inventory (FBI) and for frontal/executive function, cognition, anxiety/depression, and motor functions. Data from 146 subjects were analyzed: ALS (92), ALS-bvFTD (6), bvFTD (16), and healthy controls (32). The internal consistency of the ALS-FTD-Q-J was good (Cronbach α=0.92). The ALS-FTD-Q-J showed construct validity as it exhibited a high correlation with the FBI (r=0.79). However, correlations were moderate with anxiety/depression and low with cognitive scales, in contrast to the original report, i.e. a moderate correlation with cognition and a low correlation with anxiety/depression. The ALS-FTD-Q-J discriminated ALS patients from (ALS-)bvFTD patients and controls. Thus, the ALS-FTD-Q-J is useful for evaluating Japanese ALS/FTD patients. PMID:27423564

  5. Japanese version of the ALS-FTD-Questionnaire (ALS-FTD-Q-J).

    Science.gov (United States)

    Watanabe, Yasuhiro; Beeldman, Emma; Raaphorst, Joost; Izumi, Yuishin; Yoshino, Hiide; Masuda, Michihito; Atsuta, Naoki; Ito, Satoru; Adachi, Tadashi; Adachi, Yoshiki; Yokota, Osamu; Oda, Masaya; Hanashima, Ritsuko; Ogino, Mieko; Ichikawa, Hiroo; Hasegawa, Kazuko; Kimura, Hideki; Shimizu, Toshio; Aiba, Ikuko; Yabe, Hayato; Kanba, Makoto; Kusumi, Kimiyoshi; Aoki, Tetsuya; Hiroe, Yu; Watanabe, Hirohisa; Nishiyama, Kazutoshi; Nomoto, Masahiro; Sobue, Gen; Nakashima, Kenji

    2016-08-15

    Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) share common clinical, genetic and neuropathological features. Some ALS patients have behavioral/personality changes, which could result in significant obstacles in the care provided by family members and caregivers. An easy screening tool would contribute greatly to the evaluation of these symptoms. We translated the ALS-FTD-Questionnaire, developed in the Netherlands, into Japanese (ALS-FTD-Q-J) and examined the clinimetric properties (internal consistency, construct and clinical validity). Patients with ALS and/or behavioral variant FTD (bvFTD) were evaluated alongside healthy controls in this multicenter study. All ALS patients, regardless of bvFTD status, were further evaluated by the frontal behavioral inventory (FBI) and for frontal/executive function, cognition, anxiety/depression, and motor functions. Data from 146 subjects were analyzed: ALS (92), ALS-bvFTD (6), bvFTD (16), and healthy controls (32). The internal consistency of the ALS-FTD-Q-J was good (Cronbach α=0.92). The ALS-FTD-Q-J showed construct validity as it exhibited a high correlation with the FBI (r=0.79). However, correlations were moderate with anxiety/depression and low with cognitive scales, in contrast to the original report, i.e. a moderate correlation with cognition and a low correlation with anxiety/depression. The ALS-FTD-Q-J discriminated ALS patients from (ALS-)bvFTD patients and controls. Thus, the ALS-FTD-Q-J is useful for evaluating Japanese ALS/FTD patients.

  6. Interfacial reactions in Al/Ni multilayers

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, F.; Greer, A.L. [Cambridge Univ. (United Kingdom). Dept. of Metallurgy and Materials Science

    1998-08-01

    In thin-film multilayers, the reactions at the interfaces can proceed quite differently from those in bulk samples because of the short diffusion distances involved. In the present work Al/Ni multilayers have been made by DC magnetron sputtering. The initial Ni and Al layers have strong (111) texture. The reactions taking place have been studied in relation to the layer thickness and film structure (grain size and texture). Also multilayers have been made with alloy layers Al/Ni(Al). Typically, differential scanning calorimetry shows a sequence of reactions on heating. X-ray diffraction, including texture goniometry, has been used to identify the compounds produced. In common with earlier work, it is found that Al{sub 3}Ni is the first phase to form, but the present results differ from those reported previously in that the Al{sub 3}Ni{sub 2} phase is not formed in the course of phase evolution. The difference from the earlier results is attributed to the sharper texture in the films in the present work. Thus it is concluded that for Al/Ni multilayers, reaction sequences can be affected by crystallographic orientation, as well as other factors. (orig.) 13 refs.

  7. Magnetism in bcc Fe-Al alloy

    Energy Technology Data Exchange (ETDEWEB)

    Elzain, M.E. [Sultan Qaboos Univ., Al-Khod (Oman). Dept. of Phys.; Yousif, A.A. [Sultan Qaboos Univ., Al-Khod (Oman). Dept. of Phys.

    1994-11-01

    The magnetic moment {mu}, hyperfine field B{sub hf} and isomer shift IS at the Fe site in bcc Fe-Al alloys were calculated from first principle. Contrary to the belief that Al atoms reside in the iron lattice as magnetic holes, it was found that the local magnetic moment of Fe is decreased when Al is at a nearest neighbour site (NN), while it increases if Al is at a next-nearest neighbour site (NNN). Consequently, the average {mu} per Fe atom was found to be, initially, independent of Al content. Assuming a linear dependence of {mu}{sub Fe} on the number of Al atoms at NN and NNN sites, we calculated the average {mu}, which was found to agree with experimental results of cold worked alloys for disordered Fe-Al alloy. On the other hand, antiferromagnetic coupling appears in the CsCl ordered structures. The average B{sub hf} was also calculated and compared to experimental data and the trends in the IS are considered. (orig.)

  8. WAHDAT AL WUJUD DALAM PEMIKIRAN IBNU ARABI

    Directory of Open Access Journals (Sweden)

    Abd Halim Rofi'ie

    2013-09-01

    Full Text Available Ibnu Arabi, the Grand Master of Islam, is a great thinker whose controversial thought, wahdat al-wujud, has significantly influenced the mystiques of Islam. The meaning of wahdat al-wujud is basically two folds, i.e. that Being is the only One which exists and that the universe is merely a manifestation of the One. The One Being here refers to Allah SWT. The One covers up all the existing phenomena and functions as a resource which emanates the entire universe. In this context, He is referred to as al-Haqiqat al-Muhammadiyah. He might also be viewed as both the Universal Soul for His being the source of cosmos that governs the universe and the Universal Body for His reflecting any actions on every single micro existence that forms the universe. Furthermore, when His existence is deemed as a jauhar (jewel that face-up any occurrences, He is typically known as al-haba’. The concept of wahdat al-wujud can actually be simplified into the principle of laa maujuda illa wujud al-wahid (no existence except the Existing One, the Being. The One might reveal His own existence into different martabat or levels: Martabat Ahadiyah, Martabat Wahidiyah, and Martabat Tajalli Syuhudi. Those standing points trigger Ibnu Arabi to believe that any kinds of realities or existences are nothing but a true reflection of the One.

  9. Arsenate uptake by Al nanoclusters and other Al-based sorbents during water treatment.

    Science.gov (United States)

    Mertens, Jasmin; Rose, Jérôme; Wehrli, Bernhard; Furrer, Gerhard

    2016-01-01

    In many parts of the world, arsenic from geogenic and anthropogenic sources deteriorates the quality of drinking water resources. Effective methods of arsenic removal include adsorption and coagulation with iron- and aluminum-based materials, of which polyaluminum chloride is widely employed as coagulant in water treatment due to its low cost and high efficiency. We compared the arsenic uptake capacity and the arsenic bonding sites of different Al-based sorbents, including Al nanoclusters, polyaluminum chloride, polyaluminum granulate, and gibbsite. Extended X-ray absorption fine structure (EXAFS) spectroscopy revealed that As(V) forms bidentate-binuclear complexes in interaction with all Al-based removal agents. The octahedral configuration of nanoclusters and the distribution of sorption sites remain the same in all types of removal agents consisting of nano-scale Al oxyhydroxide particles. The obtained distances for As(V)-O and As(V)-Al agreed with previously published data and were found to be 1.69 ± 0.02 Å and 3.17-3.21 Å, respectively. Our study suggests that As(V) binds to Al nanoclusters as strongly as to Al oxide surfaces. The As sorption capacity of Al nanoclusters was found to be very similar to that of Al clusters in a polyaluminum chloride. The most efficient Al-based sorbents for arsenic removal were Al nanoclusters, followed by polyaluminum granulate. PMID:26613179

  10. Tracing Al Shabaab’s Decision to Cooperate with Al Qaeda in Somalia (2008

    Directory of Open Access Journals (Sweden)

    Adlini Ilma Ghaisany Sjah

    2014-02-01

    Full Text Available 'Al Shabaab, a Somali insurgent with predominantly nationalistic causes (alongside transnational [global Jihad] and Islamic goals made the choice to fight on behalf of Al Qaeda in 2008. The decision to do so contrasted with Al Shabaab’s previous behaviour of actively denying cooperation and distancing itself from Al Qaeda. This study aims to uncover factors that contributed to Al Shabaab’s decision through the use of process-tracing. The results show that Al Shabaab’s declaration of cooperation with Al Qaeda in August 2008 was brought about by a series of events that traced back to four factors: public reactions to the implementation of a Salafi ideology, the shift to a radical leadership, Al Shabaab’s inability to maintain stability in areas under its control and its increasing attacks by Al Shabaab on the Somali public. Al Shabaab pursued cooperation with Al Qaeda after realizing that their nationalistic preference was no longer achievable in the near future.' ' '

  11. Electrical investigations of AlGaN/AlN structures for LEDs on Si(111)

    Energy Technology Data Exchange (ETDEWEB)

    Witte, H.; Rohrbeck, A.; Guenther, K.M.; Saengkaew, P.; Blaesing, J.; Dadgar, A.; Krost, A. [Department of Semiconductor Epitaxy, Institute of Experimental Physics, University of Magdeburg, 39106 Magdeburg (Germany)

    2011-07-15

    The carrier transport in AlGaN light emission diode (LED) structures on Si-substrates including an AlN multilayer (ML) buffer for reduction of defects was investigated using I-V-characteristics and admittance spectroscopy. Additionally, AlN on Si ML and AlN/AlGaN:Si on Si structures were grown and analyzed separately. The AlN-ML/AlGaN:Si heterojunction, and the pn-junction including the AlGaN/GaN multi quantum well (MQW)-structure were identified. As the main space charge regions (SCRs) controlling the carrier transport through the ultraviolet-light emission diode (UV-LED) structure the Si-substrate/AlN-ML heterojunctions pointed out. The I-V-characteristic of the LED structure is described by the series resistance of the AlN-ML and a parallel resistance with respect to the pn-junction. Interface defect states and/or deep defects impact the series resistance. The carrier transport through the LED structure is controlled by a tunnel process described by a Fowler-Nordheim (FN)-emission mainly through the AlN-ML buffer forming the series resistance. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  12. Kritik al-Ghazali terhadap Kekekalan Alam

    OpenAIRE

    Sahidi Mustafa

    2015-01-01

    The concept of the creation of universe offered by Neo-Platonism philosopher such as al-Kindi, al-Farabi, and Ibnu Sina are philosophical concept existed and came as an early moment of development of Islamic philosophy interrelated to God, ultimately about his Existence and Characteristics. One of the topics is how God created the universe. According to al-Farabi and Ibnu Sina, God created this universe by way of emanation in order to prevent Himself from the new attitudes. Consequently, univ...

  13. Amyotrofinen lateraaliskleroosi (ALS) ja potilaan ohjaus

    OpenAIRE

    Korkeaniemi, Lotta; Kaakinen, Leena

    2009-01-01

    Saimme opinnäytetyömme toimeksiantona Hyvinkään sairaalan sisätautien vuodeosastolta. Tavoitteena oli luoda ALS potilaille potilasopas trakeostomiasta ja sen kanssa elämisestä. Oppaan tarkoituksena on auttaa ALS potilaita päättämään, kuinka pitkälle he haluavat viedä heidän hengitystukihoitonsa. Samalla hoitajat saavat tuki materiaalia, jonka avulla he voivat käydä läpi hengitystukihoitoja ja erityisesti trakeostomiaan liittyviä asioita. ALS eli amyotrofinen lateraaliskleroosi on tahdona...

  14. The wobbler mouse, an ALS animal model

    DEFF Research Database (Denmark)

    Moser, Jakob Maximilian; Bigini, Paolo; Schmitt-John, Thomas

    2013-01-01

    This review article is focused on the research progress made utilizing the wobbler mouse as animal model for human motor neuron diseases, especially the amyotrophic lateral sclerosis (ALS). The wobbler mouse develops progressive degeneration of upper and lower motor neurons and shows striking...... similarities to ALS. The cellular effects of the wobbler mutation, cellular transport defects, neurofilament aggregation, neuronal hyperexcitability and neuroinflammation closely resemble human ALS. Now, 57 years after the first report on the wobbler mouse we summarize the progress made in understanding...

  15. Thermal diffusion in Ni/Al multilayer

    Energy Technology Data Exchange (ETDEWEB)

    Swain, M.; Bhattacharya, D.; Singh, S.; Basu, S. [Solid State Physics Division, Bhabha Atomic Research Center, Mumbai 400085 (India); Gupta, M. [UGC-DAE-Consortium for Scientific Research, University Campus, Khandwa Road, Indore 452017 (India)

    2013-02-05

    Two Ni/Al multilayers deposited by ion beam sputtering of nominal design [Ni(200A)/Al(100A)] Multiplication-Sign 5 and [Ni(50A)/Al(227A)] Multiplication-Sign 5 on Si substrates were annealed at 200 Degree-Sign C. As-deposited and annealed samples were characterized by x-ray diffraction (XRD) and x-ray reflectometry (XRR). The effort was to study the path of alloying in the above two multilayers of same elements but of opposite stoichiometric ratio. We find distinct differences in alloying of these samples.

  16. Linija za transport Al-polizdelkov

    OpenAIRE

    Capl, Žiga

    2012-01-01

    V diplomski nalogi je predstavljena linija za transport Al-polizdelkov, ki je sestavljena iz dveh verižnih transporterjev in dveh manipulatorjev. Omenjeni transporterji morajo transportirati Al-polizdelke od sprejemnega mesta do poti v stiskalnico. V okviru diplomskega dela smo opravili analizo obstoječega ogrodja z naklonom, linije za transport Al-polizdelkov in podali možne rešitve za novo učinkovitejšo izvedbo. Na podlagi tehnično-tehnoloških zahtev smo izbrali najprimernejšo rešitev i...

  17. The Ni-Al-Hf Multiphase Diffusion

    Directory of Open Access Journals (Sweden)

    Romanowska J.

    2016-06-01

    Full Text Available The generalized Darken method was applied to simulate the diffusion between γ-Ni| γ’-Ni3Al and γ’-Ni3Al|β-NiAl interfaces. The results of calculations were compared with the experimental concentration’s profiles of nickel, aluminum and hafnium in aluminide and hafnium doped aluminide coatings deposited by the CVD and PVD methods on pure nickel. The method deals with the Wagner’s integral diffusion coefficients and thermodynamic data - activities of components. The experimental results agree with the simulated ones.

  18. Die Poetik als Teil des aristotelischen Organon

    OpenAIRE

    Wels, Volkhard

    2016-01-01

    Der Aufsatz umreißt die Wirkung von Averroes’ Bearbeitung der aristotelischen ‚Poetik‘ als argumentativer Disziplin. Beginnend mit Al-Farabi und Al-Gazali im zehnten Jahrhundert wird die ‚Poetik‘ den logischen Disziplinen des ‚Organon‘ zugerechnet. Während die Theorie eines ‚poetischen Syllogismus‘ nicht rezipiert worden ist, wurde der argumentative Status der Dichtung vom zwölften Jahrhundert an auch im lateinischen Westen bekannt. Mit unterschiedlichen Begründungen übernahmen Dominicus Gund...

  19. TAFSIR SEMANTIK TERHADAP SURAT AL-KAFIRUN

    Directory of Open Access Journals (Sweden)

    Imam Muslimin

    2011-10-01

    Full Text Available The problems about the reading of al-Qur’an is always interesting to be discussed, in which the use of Arabic includes sound or ‘nash’ is acrucial factor to understand the implicit meaning of the Arabic-written texts. Al-Qur’an discusses problem based on the society’s culture. Al-Kafirun discusses not only about the normative theology but more about sociological contexts in which it tends to show transparency, fight against fanaticism and regionalism. And all of the will bring to the first process of the making of the text meaning to the situational context that creates them.

  20. InAlN/AlN/GaN heterostructures for high electron mobility transistors

    Science.gov (United States)

    Usov, S. O.; Sakharov, A. V.; Tsatsulnikov, A. F.; Lundin, V. W.; Zavarin, E. E.; Nikolaev, A. E.; Yagovkina, M. A.; Zemlyakov, V. E.; Egorkin, V. I.; Ustinov, V. M.

    2016-08-01

    The results of development of InAlN/AlN/GaN heterostructures, grown on sapphire substrates by metal-organic chemical vapour deposition, and high electron mobility transistors (HEMTs) based on them are presented. The dependencies of the InAlN/AlN/GaN heterostructure properties on epitaxial growth conditions were investigated. The optimal indium content and InAlN barrier layer thicknesses of the heterostructures for HEMT s were determined. The possibility to improve the characteristics of HEMTs by in-situ passivation by Si3N4 thin protective layer deposited in the same epitaxial process was demonstrated. The InAlN/AlN/GaN heterostructure grown on sapphire substrate with diameter of 100 mm were obtained with sufficiently uniform distribution of sheet resistance. The HEMTs with saturation current of 1600 mA/mm and transconductance of 230 mS/mm are demonstrated.

  1. Oxidation of Al2O3 continuous fiber-reinforced/NiAl composites

    Science.gov (United States)

    Doychak, J.; Nesbitt, J. A.; Noebe, R. D.; Bowman, R. R.

    1992-01-01

    The 1200 C and 1300 C isothermal and cyclic oxidation behavior of Al2O3 continuous fiber-reinforced/NiAl composites were studied. Oxidation resulted in formation of Al2O3 external scales in a similar manner as scales formed on monolithic NiAl. The isothermal oxidation of an Al2O3/NiAl composite resulted in oxidation of the matrix along the fiber/matrix interface near the fiber ends. This oxide acted as a wedge between the fiber and the matrix, and, under cyclic oxidation conditions, led to further oxidation along the fiber lengths and eventual cracking of the composite. The oxidation behavior of composites in which the Al2O3 fibers were sputter coated with nickel prior to processing was much more severe. This was attributed to open channels around the fibers which formed during processing, most likely as a result of the diffusion of the nickel coating into the matrix.

  2. AlON粉体的合成%Synthesis of AlON Powder

    Institute of Scientific and Technical Information of China (English)

    赵小军; 茹红强; 张宁; 孙有政

    2009-01-01

    以α-Al_2O_3和AlN为原料,利用高温固相反应在氮气气氛下常压合成了AlON粉体.研究了成分配比、合成温度、保温时间对合成AlON粉体含量的影响,并通过热分析测试了合成过程热流和质量的变化.结果表明,当原料Al_2O_3和AlN的质量比为81:18、合成工艺为1750 ℃, 2 h时,得到AlON相的含量达到95%以上.

  3. A Rechargeable Al/S Battery with an Ionic-Liquid Electrolyte.

    Science.gov (United States)

    Gao, Tao; Li, Xiaogang; Wang, Xiwen; Hu, Junkai; Han, Fudong; Fan, Xiulin; Suo, Liumin; Pearse, Alex J; Lee, Sang Bok; Rubloff, Gary W; Gaskell, Karen J; Noked, Malachi; Wang, Chunsheng

    2016-08-16

    Aluminum metal is a promising anode material for next generation rechargeable batteries owing to its abundance, potentially dendrite-free deposition, and high capacity. The rechargeable aluminum/sulfur (Al/S) battery is of great interest owing to its high energy density (1340 Wh kg(-1) ) and low cost. However, Al/S chemistry suffers poor reversibility owing to the difficulty of oxidizing AlSx . Herein, we demonstrate the first reversible Al/S battery in ionic-liquid electrolyte with an activated carbon cloth/sulfur composite cathode. Electrochemical, spectroscopic, and microscopic results suggest that sulfur undergoes a solid-state conversion reaction in the electrolyte. Kinetics analysis identifies that the slow solid-state sulfur conversion reaction causes large voltage hysteresis and limits the energy efficiency of the system. PMID:27417442

  4. Characterization of AlInN/AlN/GaN Heterostructures with Different AlN Buffer Thickness

    Science.gov (United States)

    Çörekçi, S.; Dugan, S.; Öztürk, M. K.; Çetin, S. Ş.; Çakmak, M.; Özçelik, S.; Özbay, E.

    2016-07-01

    Two AlInN/AlN/GaN heterostructures with 280-nm- and 400-nm-thick AlN buffer grown on sapphire substrates by metal-organic chemical vapor deposition (MOCVD) have been investigated by x-ray diffraction (XRD), atomic force microscopy (AFM), photoluminescence (PL) and Hall-effect measurements. The symmetric (0002) plane with respect to the asymmetric (10bar{1}2) plane in the 280-nm-thick AlN buffer has a higher crystal quality, as opposed to the 400-nm-thick buffer. The thinner buffer improves the crystallinity of both (0002) and (10bar{1}2) planes in the GaN layers, it also provides a sizeable reduction in dislocation density of GaN. Furthermore, the lower buffer thickness leads to a good quality surface with an rms roughness of 0.30 nm and a dark spot density of 4.0 × 108 cm-2. The optical and transport properties of the AlInN/AlN/GaN structure with the relatively thin buffer are compatible with the enhancement in its structural quality, as verified by XRD and AFM results.

  5. Evolution of ConAl clusters and chemisorption of hydrogen on ConAl clusters

    International Nuclear Information System (INIS)

    The growth behavior of ConAl (n = 1–15) and the chemisorptions of hydrogen on the ground state geometries have been studied using the density functional theory (DFT) within the generalized gradient approximation (GGA). The growth pattern for ConAl is Al-substituted Con+1 clusters, and it keeps the similar frameworks of the most stable Con+1 clusters except for n = 2, 3, and 6. The Al atom substitutes the surface atom of the Con+1 clusters for n ≤ 13. Starting from n = 14, the Al atom completely falls into the center of the Co-frame. The dissociation energy, the second-order energy differences, and the HOMO–LUMO gaps indicate that the magic numbers of the calculated ConAl clusters are 7, 9, and 13, corresponding to the high symmetrical structures. To my knowledge, this is the first time that a systematic study of chemisorption of hydrogen on cobalt aluminum clusters. The twofold bridge site is identified to be the most favorable chemisorptions site for one hydrogen adsorption on ConAl (n = 1–6, 8, 10), and two hydrogen adsorption on ConAl (n = 1–7), while threefold hollow site is preferred for one hydrogen adsorption on ConAl (n = 7, 9, 11–15) and two hydrogen adsorption on ConAl (n = 8–10, 12–15) clusters. The ground state structure of two hydrogen adsorption on Co11Al is exceptional. In general, the binding energy of both H and 2H of ConAl (n = 1–12) is found to increase with the cluster size. And the result shows that large binding energies of the hydrogen atoms and large fragmentation energies for Co11AlH and Co12AlH make these species behaving like magic clusters.

  6. Wali Allah menurut al-Hakim al-Tirmidzi dan Ibnu Taimiyyah

    Directory of Open Access Journals (Sweden)

    Lilik Mursito

    2015-12-01

    Full Text Available The discussion about wali presented in the early time on the hand of al-Hakim al Tirmidzi, which reaps number of responses from Muslim scholar because of his misleading. One of them is Ibn Taimiyyah. Al-Hakim and Ibn Taymiyyah have their own view about wali with several distinctions. In the definition of wali, al-Hakim al-Tirmidzi used more general language than Ibn Taimiyyah, as well as characteristics, how to be wali, the classification, concept of karamah, and the concept of khatm al-awliya’. According to writer, al-Hakim al-Tirmidzi’s view about wali able to deepen our understanding about Sufism, meanwhile Ibn Taimiyyah’s view will led us to comprehend Sufism from modernist point of view. This paper conclude that: both of figures seen that wali of Allah are the servants submissive and obedient in running His command; according to al-Hakim al Tirmidzi, degree of wali can be reached purely from Allah’s bounty and the effort of servants themselves, while Ibn Taimiyyah seen that the degree could be reached in the way of faith and piety of the servant; al-Hakim al-Tirmidzi seen that karamah is the most urgent for wali, while Ibn Taimiyyah did not; al-Hakim al-Tirmidzi utilized the quality of deeds to measure the best people and purity of heart to measure the best wali, while Ibn Taymiyyah utilized the quality of deeds as the assessment standard to measure best people and wali.

  7. In Situ Fabrication of AlN Coating by Reactive Plasma Spraying of Al/AlN Powder

    Directory of Open Access Journals (Sweden)

    Mohammed Shahien

    2011-10-01

    Full Text Available Reactive plasma spraying is a promising technology for the in situ formation of aluminum nitride (AlN coatings. Recently, it became possible to fabricate cubic-AlN-(c-AlN based coatings through reactive plasma spraying of Al powder in an ambient atmosphere. However, it was difficult to fabricate a coating with high AlN content and suitable thickness due to the coalescence of the Al particles. In this study, the influence of using AlN additive (h-AlN to increase the AlN content of the coating and improve the reaction process was investigated. The simple mixing of Al and AlN powders was not suitable for fabricating AlN coatings through reactive plasma spraying. However, it was possible to prepare a homogenously mixed, agglomerated and dispersed Al/AlN mixture (which enabled in-flight interaction between the powder and the surrounding plasma by wet-mixing in a planetary mill. Increasing the AlN content in the mixture prevented coalescence and increased the nitride content gradually. Using 30 to 40 wt% AlN was sufficient to fabricate a thick (more than 200 µm AlN coating with high hardness (approximately 1000 Hv. The AlN additive prevented the coalescence of Al metal and enhanced post-deposition nitriding through N2 plasma irradiation by allowing the nitriding species in the plasma to impinge on a larger Al surface area. Using AlN as a feedstock additive was found to be a suitable method for fabricating AlN coatings by reactive plasma spraying. Moreover, the fabricated coatings consist of hexagonal (h-AlN, c-AlN (rock-salt and zinc-blend phases and certain oxides: aluminum oxynitride (Al5O6N, cubic sphalerite Al23O27N5 (ALON and Al2O3. The zinc-blend c-AlN and ALON phases were attributed to the transformation of the h-AlN feedstock during the reactive plasma spraying. Thus, the zinc-blend c-Al

  8. Pesticides Linked to Raised Risk of ALS

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_158737.html Pesticides Linked to Raised Risk of ALS One toxin ... MONDAY, May 9, 2016 (HealthDay News) -- Exposure to pesticides and other chemicals may increase the risk for ...

  9. Data used in Xu et al., 2016

    Data.gov (United States)

    U.S. Environmental Protection Agency — Mercury emissions data from anthropogenic sources as described in Xu et al., 2016. This dataset is associated with the following publication: Xu, X., N. Liu, M....

  10. Smoking Tied to Shorter Survival with ALS

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_161094.html Smoking Tied to Shorter Survival With ALS Tobacco use ... 22, 2016 WEDNESDAY, Sept. 21, 2016 (HealthDay News) -- Smoking may speed progression of Lou Gehrig's disease and ...

  11. Het Nederlandse bos als vorm van bodemgebruik

    NARCIS (Netherlands)

    Slangen, L.H.G.; Boven, van B.

    1983-01-01

    Behandeling van de oppervlakte en verdeling van het bos en de veranderingen die hierin zijn opgetreden, met de bedrijfsgrootte-struktuur als belangrijke invalshoek daarbij; de rol van de overheid: doeleinden, instrumenten en effekten van het beleid

  12. Thermal Conductivity of Al-Salt Composites

    Science.gov (United States)

    Li, Peng; Zhang, Mei; Wang, Lijun; Seetharaman, Seshadri

    2015-11-01

    With a view to examine the possibility of estimating the content of entrapped metallic aluminium in the salt cake from aluminium remelting, the thermal diffusivity of reference composites of KCl-NaCl-Al was measured as a function of aluminium metal content at room temperature. The thermal conductivity of the reference composites was found to increase with the metallic Al content. The lumped parameter model approach was carried out to discuss the influence of different geometry arrangements of each phase, viz. air, salts and metallic aluminium on the thermal conductivity. Application of the present results to industrial samples indicates that factors such as the interfacial condition of metallic Al particles have to be considered in order to estimate the amount of entrapped Al in the salt cake.

  13. Pesticides Linked to Raised Risk of ALS

    Science.gov (United States)

    ... nlm.nih.gov/medlineplus/news/fullstory_158737.html Pesticides Linked to Raised Risk of ALS One toxin ... MONDAY, May 9, 2016 (HealthDay News) -- Exposure to pesticides and other chemicals may increase the risk for ...

  14. Calcium platinum aluminium, CaPtAl

    Directory of Open Access Journals (Sweden)

    Charles Fon Abi

    2011-10-01

    Full Text Available A preliminary X-ray study of CaPtAl has been reported previously by Hulliger [J. Alloys Compd (1993, 196, 225–228] based on X-ray powder diffraction data without structure refinement. With the present single-crystal X-ray study, we confirm the assignment of the TiNiSi type for CaPtAl, in a fully ordered inverse structure. All three atoms of the asymmetric unit have .m. site symmetry. The structure features a ∞3[AlPt] open framework with a fourfold coordination of Pt by Al atoms and vice versa. The Ca atoms are located in the large channels of the structure.

  15. Stem Cells Deemed Safe for ALS Patients

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_159627.html Stem Cells Deemed Safe for ALS Patients But further research needed to see if injections into spine would provide any benefit, researchers say To use the sharing features on ...

  16. Del sombrero al árbol. Relatos icónicos de la nación colombiana

    Directory of Open Access Journals (Sweden)

    González Aranda, Beatriz

    2009-12-01

    ó debido a la declaración de Independencia. Una obra de autor anónimo puede considerarse como la representación de la ceremonia de la siembra del árbol. Se analiza el tránsito tan arraigado del concepto de patria, a su desprestigio y en la actualidad, a su reivindicación. El tercer episodio narra de cómo llegó a convertirse en icono el Poporo quimbaya, entre las cerca de 33.600 piezas del Museo del Oro del Banco de la República. Su forma geométrica, el material y mito de El Dorado, contribuyeron a su iconización. El cuarto episodio trata de la Virgen de Chiquinquirá (La Chinca (1556 vinculada al milagro de la renovación en la sociedad colonia. Se conecta la colonia con la independencia, la devoción con la nacionalidad. Se concluye con una pregunta sobre ¿Quién crea las representaciones de la nacionalidad, el artista, el pueblo, los museos? y sobre la validez de las representaciones iconográficas.

  17. Preparation of TiAl/Ti2AlC Composites with Ti/Al/C Powders by In-situ Hot Pressing

    Institute of Scientific and Technical Information of China (English)

    MEI Bingchu; YAN Ming; ZHU Jiaoqun; ZHOU Weibing

    2006-01-01

    TiAl/Ti2AlC composites were prepared by in-situ hot pressing of Ti/Al/C powders mixtures and sintered at different temperatures were investigated by X-ray diffraction (XRD) of samples. The reaction procedure of Ti-Al-C system could be divided into three stages. Below 900 ℃, Ti reacts with Al to form TiAl intermetallics; above 900 ℃, C reacts with remain Ti to form TiC triggered by the exothermal reaction of Ti and Al; TiAl reacts with TiC to produce dense TiAl/Ti2AlC composites. In the holding stage, ternary Ti2AlC develops to layered polycrystal and composites pyknosis in the meanwhile. The mechanism of synthesis and microstructure was especially discussed.

  18. Del latín al rumano

    Directory of Open Access Journals (Sweden)

    Montes Giraldo José Joaquín

    2003-06-01

    Full Text Available

    Marius Sala, Del latín al rumano. Versión española de Valeria Neagu, París, Unión Latina - Bucarest, Univers enciclopedic, 2002. El texto se dirige al lector corriente, no especialista, y por eso el aparato técnico-bibliográfico no se presenta en el curso de la exposición.

  19. Effects of Al substitution on goethite formation

    OpenAIRE

    Premoli, Alessandra Maria; Melis, Pietro; Gessa, Carlo Emanuele; Deiana, Salvatore Andrea

    1984-01-01

    Goethites containing up to 32.7 mole % Al were synthesized and characterized through diffractometry, spectrometry, DSC and chemical techniques. Results indicate that crystal growth was favoured or hindered depending on the percentage of aluminum incorporated into the structure. Goethites to which 5-10 mole % Al were initially added crystallized best, as shown by the highest crystallite dimensions calculated from X-ray and Mössbauer analyses, and by the lowest surface areas values. Over suc...

  20. Information als Gegenstand von Informationskompetenz. Eine Begriffsanalyse

    OpenAIRE

    Ingold, Marianne

    2011-01-01

    Der Informationsbegriff als zentraler Gegenstand von Informationskompetenz wird in der bibliothekarischen Diskussion in der Regel nicht explizit thematisiert, sondern lässt sich aus Fachliteratur und Bibliothekspraxis nur implizit erschließen. Eine theoretische Beschäftigung mit dem Informationsbegriff ist jedoch unabdingbar, soll das Konzept "Informationskompetenz" auch außerhalb des bibliothekarischen Kontextes verständlich und nutzbar gemacht werden. Im vorliegenden Text, der sich als B...

  1. Anerkennung als Voraussetzung gesellschaftlicher und unternehmerischer Teilhabe

    OpenAIRE

    Eurich, Johannes; Brink, Alexander

    2003-01-01

    Angesichts des neuen Phänomens der sozialen Exklusion wird soziale Gerechtigkeit nicht mehr nur über die Verteilung von Gütern hergestellt, vielmehr spielt auch die Ebene der Partizipation eine Rolle. Anerkennung ist eine Grundvoraussetzung für Partizipation. Die Verfasser diskutieren Fragen der Unternehmensethik auf der Dimension der Anerkennung. Sie votieren für ein normatives Stakeholder-Management als freiwillige Verpflichtung, das auch strategischen Anforderungen gerecht werden kann. Als...

  2. Communication Support for People with ALS

    OpenAIRE

    David Beukelman; Susan Fager; Amy Nordness

    2011-01-01

    Almost all people with amyotrophic lateral sclerosis (ALS) experience a motor speech disorder, such as dysarthria, as the disease progresses. At some point, 80 to 9 5 % of people with ALS are unable to meet their daily communication needs using natural speech. Unfortunately, once intelligibility begins to decrease, speech performance often deteriorates so rapidly that there is little time to implement an appropriate augmentative and alternative communication (AAC) intervention; therefore, app...

  3. In situ (Al3Zr + Al2O3np)/2024Al metal matrix composite with novel reinforcement distributions fabricated by reaction hot pressing

    International Nuclear Information System (INIS)

    Highlights: •(Al3Zr + Al2O3np)/2024Al MMC with a novel network distribution was tailored. •Al3Zr and Al2O3np were in situ synthesized at 740 °C using the 2024Al–ZrO2 system. •The effect of sintering parameters on Al3Zr morphology was investigated. •Influence of Al3Zr morphology on tensile properties of the composite was studied. -- Abstract: In situ hybrid (Al3Zr + Al2O3np)/2024Al metal matrix composites with unique controlled reinforcement distributions were fabricated using low energy ball milling and reactive hot pressing. The reaction system between 2024Al and ZrO2 was studied using differential thermal analysis (DTA). In situ formed aluminium oxide (Al2O3) and zirconium tri-aluminide (Al3Zr) with varying morphology and sizes were produced under different fabricating conditions. Al3Zr with varying morphologies such as particle, plate and flakes were observed. With a total 10 vol.% of reinforcements, the composite containing a three-dimensional network of closely spaced in situ synthesized Al3Zr and Al2O3 particles had a YS of 175 MPa and a UTS of 261 MPa, effectively strengthening the 2024Al matrix. The effect of different sintering conditions on the microstructure and tensile properties of the composite was systematically investigated

  4. Thermodynamics and surface properties of liquid Al-Ga and Al-Ge alloys

    Energy Technology Data Exchange (ETDEWEB)

    Anusionwu, B.C. [Abdus Salam Int. Centre for Theoretical Physics, Trieste (Italy); Federal University of Technology, Department of Physics, Owerri (Nigeria); Adebayo, G.A. [Abdus Salam Int. Centre for Theoretical Physics, Trieste (Italy); University of Agriculture, Department of Physics, Abeokuta (Nigeria); Madu, C.A. [Federal University of Technology, Department of Physics, Owerri (Nigeria)

    2009-11-15

    The surface properties of Al-Ga and Al-Ge liquid alloys have been theoretically investigated at a temperature of 1100 K and 1220 K respectively. For the Al-Ga system, the quasi chemical model for regular alloy and a model for phase segregating alloy systems were applied, while for the Al-Ge system the quasi chemical model for regular and compound forming binary alloys were applied. In the case of Al-Ga, the models for the regular alloys and that for the phase segregating alloys produced the same value of order energy and same values of thermodynamic and surface properties, while for the Al-Ge system, the model for the regular alloy reproduced better the thermodynamic properties of the alloy. The model for the compound forming systems showed a qualitative trend with the measured values of the thermodynamic properties of the Al-Ge alloy and suggests the presence of a weak complex of the form Al{sub 2}Ge{sub 3}. The surface concentrations for the alloys show that Ga manifests some level of surface segregation in Al-Ga liquid alloy while the surface concentration of Ge in Al-Ge liquid alloy showed a near Roultian behavior below 0.8 atomic fraction of Ge. (orig.)

  5. Thermodynamics and surface properties of liquid Al-Ga and Al-Ge alloys

    Science.gov (United States)

    Anusionwu, B. C.; Adebayo, G. A.; Madu, C. A.

    2009-11-01

    The surface properties of Al-Ga and Al-Ge liquid alloys have been theoretically investigated at a temperature of 1100 K and 1220 K respectively. For the Al-Ga system, the quasi chemical model for regular alloy and a model for phase segregating alloy systems were applied, while for the Al-Ge system the quasi chemical model for regular and compound forming binary alloys were applied. In the case of Al-Ga, the models for the regular alloys and that for the phase segregating alloys produced the same value of order energy and same values of thermodynamic and surface properties, while for the Al-Ge system, the model for the regular alloy reproduced better the thermodynamic properties of the alloy. The model for the compound forming systems showed a qualitative trend with the measured values of the thermodynamic properties of the Al-Ge alloy and suggests the presence of a weak complex of the form Al2Ge3. The surface concentrations for the alloys show that Ga manifests some level of surface segregation in Al-Ga liquid alloy while the surface concentration of Ge in Al-Ge liquid alloy showed a near Roultian behavior below 0.8 atomic fraction of Ge.

  6. Heterogeneous nucleation of solid Al from the melt by Al 3 Ti : Molecular dynamics simulations

    KAUST Repository

    Wang, Junsheng

    2010-10-27

    It has been known experimentally for some time that Al3 Ti is a powerful nucleant for the solidification of aluminum from the melt; however, a full microscopic understanding is still lacking. To develop this understanding, we have performed molecular dynamics simulations of the nucleation and early stages of growth using published embedded atom method potentials for Al-Ti, but modified by us to stabilize the D 022 structure. We discover that Al3 Ti can indeed be very effective in promoting the growth of solid Al but the manner in which growth takes place depends sensitively on the surface on which the Al nucleates. In particular, complete growth of solid Al from the liquid on the (001) and (110) surfaces of Al3 Ti occurs at a lower temperature than on the (112) surface. This anisotropy agrees with observations in previous experiments. We explain this observation in terms of interfacial energies. On the preferential (111) surface of Al the solid-liquid interfacial energy is highest while the solid-vacuum energy is lowest. Our simulations also show that the extent of ordering taking place in liquid Al close to the Al 3 Ti substrate above the melting point correlates well with the effectiveness of the substrate as a nucleant below the melting temperature: this could provide a computationally efficient scheme to identify good nucleants. © 2010 The American Physical Society.

  7. Corrosion behavior of solid solution (Ti,Al)N as a function of Al concentration

    Energy Technology Data Exchange (ETDEWEB)

    Larijani, M.M.; Seyedi, H. [Nuclear Science and Technology Research Institute, P. O. Box 31485-498, Karaj (Iran, Islamic Republic of); Manouchehrian, M. [Department of Physics, Science Faculty, South Tehran Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Yari, M. [Engineering Department Materials, Science and Research Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of)

    2012-08-15

    In this work, a series of (Ti, Al) N coatings with different Al contents were deposited on 304 stainless steel substrates by Hollow Cathode Discharge (HCD) method. The coatings were grown on 304 stainless steel substrates at 400 C. The coatings were characterized using energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), atomic force microscopy (AFM), and microhardness test. The XRD confirmed the transition from TiN phase to (Ti, Al) N phase and then to AlN phase with increasing Al concentration in the solid solution. It was found that with increasing Al concentration the hardness of the coatings initially increased up to a maximum value of about 30 GPa at around 32 at.% of Al and then the coating hardness decreased rapidly with further increase of Al content (Al > 32 at.%). The potentiodynamic polarization analysis was carried out in 3.5 wt.% NaCl solutions to study the corrosion resistance of the coatings. From the corrosion test it can be inferred that the amount of Al atoms in the coatings plays an important role for reducing the corrosion. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  8. Clinical trials for neuroprotection in ALS.

    Science.gov (United States)

    Siciliano, G; Carlesi, C; Pasquali, L; Piazza, S; Pietracupa, S; Fornai, F; Ruggieri, S; Murri, L

    2010-07-01

    Owing to uncertainty on the pathogenic mechanisms underlying motor neuron degeneration in amyotrophic lateral sclerosis (ALS) riluzole remains the only available therapy, with only marginal effects on disease survival. Here we review some of the recent advances in the search for disease-modifying drugs for ALS based on their putative neuroprotective effetcs. A number of more or less established agents have recently been investigated also in ALS for their potential role in neuroprotection and relying on antiglutamatergic, antioxidant or antiapoptotic strategies. Among them Talampanel, beta-lactam antibiotics, Coenzyme Q10, and minocycline have been investigated. Progress has also been made in exploiting growth factors for the treatment of ALS, partly due to advances in developing effective delivery systems to the central nervous system. A number of new therapies have also been identified, including a novel class of compounds, such as heat-shock protein co-inducers, which upregulate cell stress responses, and agents promoting autophagy and mitochondriogenesis, such as lithium and rapamycin. More recently, alterations of mRNA processing were described as a pathogenic mechanism in genetically defined forms of ALS, as those related to TDP-43 and FUS-TLS gene mutations. This knowledge is expected to improve our understanding of the pathogenetic mechanism in ALS and developing more effective therapies. PMID:20406180

  9. DISTINGSI DAN DIASPORA TASAWUF ABÛ AL-HASAN AL-SHÂDHILÎ

    Directory of Open Access Journals (Sweden)

    Saifulah Saifulah

    2015-09-01

    Full Text Available This article discusses Shâdhilîyah, one of the most recognized sufi orders, which possesses quite distinct aspects in the conception of its mystical teachings. This sufi order was founded by Abû al-H}asan al-Shâdhilî, a sufi who has moderate and open view of the worldly life. Al-Shâdhilî explained about how a sufi should behave towards and deal with worldly matters. Although al-Shâdhilî asserted that a person who practice tasawwuf should not pay more adoration on the worldly matters (hubb al-dunyâ, the person does not have to abhor and leave such lively aspects as wealth and position behind. The most important thing to a sufi, according to al-Shadhili, is how he obeys the requirements of shar‘ by avoiding away from immoral deeds and at the same time recognizing God in his heart (ma‘rifat Allâh. Al-Shâdhilî initiated tasawuf ‘amalî which is affiliated to the Ahl al-Sunnah wa al-Jamâ‘ah school, an Islamic mystical thought that adheres to the principles of sharî‘ah based on the foundation of al-Qur’ân dan H}adîth. The concept of al-Shâdhilî’s tasawuf has been subsequently revealed into the great sufi order spectrum, namely al-Shâdhilîyah, where during its historical development this sufi order has led to the emergence of many branches with different names.Keywords: Shâdhilîyah, open view, hubb al-dunyâ, ma‘rifat Allâh.

  10. Al4C3 Hydration Thermochemical Analysis for Burned Carbon-containing Refractories with Al

    Institute of Scientific and Technical Information of China (English)

    YANG Ding'ao; YU Zhiming; FAN Liuwu

    2003-01-01

    In this paper, X-ray diffractogram analysis and SEM observation of Al4 C3 formed at high temperature from carbon-containing refractories with Al have been carried out.Aluminum added to carbon-containing refractories reacts with C(s)to form Al4 C3(s) gradually during heating from 600 ℃ to 1200℃.It is considered that the interlocked structure of Al4 C3 plate crystals promotes the outstanding increase of hot modulus of rupture of carbon-containing refractories with Al. The HMOR of carbon-containing refractories added with Al additive from 0 to 5wt% increases by 2.8 times being from 6.5MPa to 18.2MPa.After a thermochemical calculation for hydration reaction processes of Al4 C3 and H2O(g), the equilibrium partial pressure chart of H2O(g)in H2O-Al4C3-Al(OH)3 system vs various temperatures has been attained . The H2O (g) partial pressure in the air needed for the Al4 C3 hydration reaction is no more than 10~18 atm at the temperature below 120℃.It is considered that the burned carbon-containing refractories with Al is extremely easy to hydrate and the cracking of burned carbon-containing refractories is generated because that the hydration expansion is 2.11 times during transforming from Al4 C3 to Al(OH)3.The fundamental measure against hydration of the refractories is to insulate the refractories from H2O(g)by various means such as pitch impregnation or other sealing materials.

  11. Prinsip Pendidikan Karakter dalam Islam: Studi Komparasi Pemikiran Al-Ghazali dan Burhanuddin Al-Zarnuji

    Directory of Open Access Journals (Sweden)

    Agus Setiawan

    2014-06-01

    Full Text Available The impelemtantion of character education that is done by the Indonesian government recently has been provoked by al-Ghazali and Burhanuddin al-Zarnuji long ago. It was proven by some written thoughts of al-Ghazali and Burhanuddin al-Zarnuji. They were very famous scientists in their era and widely welknown as educational experts who produced some phenomenal thoughts many people use today. Al-Ghazali and Burhanuddin al-Zarnuji lived in the era of Bani Abbasiyah monarchy, but Both of them lived in different era. Al-Ghazali was born first, then Burhanuddin al-Zarnuji. They had different mazhab, al-Ghazali went to the traditional principle of mazhab Syafi’I and Burhanuddin al-Zarnuji went to the modern principle of mazhab Hanafi. The differences, of course, would create a different thought. Still, they might have a similar principle of Islamic character education. The thoughts of character education of al-Ghazali have been poured in the “Ayyuha Walad” focusing to the students’ character building characterized by religiously obedient, skillfull of general and religious knowledge, socially helpful, affectionate, generous, good citizen, and coloring the society. Some applicable thoughts of character education of Ayyuha al-Walad of al-Gazhali to the contemporary education are: the balance of the happiness purposes of the recent life and the life after death, qana’ah and tawakal, affectionate, caring other, patience, honesty, philanthrophy, social works, generousity, democratic, peace makers, and patriotic. Those characters are also directed in the islamic character education nowdays. So that, the thoughts of al-Ghazali positively and responsively are absorbed by the Indonesian government to build the national character widely implementing in the national curriculum based on the local wisdom and the Islamic values. In the end, the students are able to live happily based on the Islamic rules by implementing the good behavior. Similar to the al

  12. Morphology of phase separation in AlN-Al2OC and SiC-AlN ceramics

    International Nuclear Information System (INIS)

    Solid solutions in the AIN-Al2OC and SiC-AlN systems were fabricated by hot-pressing powder mixtures in graphite dies. X-ray diffraction showed the samples to be single phases of 2H structure. The samples were annealed between 1600 degrees and 1900 degrees C for up to 1000 h. In the SiC-AlN system, optical microscopy and X-ray diffraction failed to reveal microstructural or phase changes. However, electron microscopy showed that samples had decomposed. Streaking of diffraction spots occurred along directions orthogonal to [012] planes (∼43 degrees off the c axis), which is approximately the direction along which the elastic energy function is a minimum. The orientation-dependent Young's modulus was also a minimum along this direction. In AlN-Al2OC, optical microscopy and X-ray diffraction indicated the occurrence of decomposition. The precipitates were disk-shaped with [001] orthogonal to the disks. The occurrence of decomposition along the [001] direction suggests that it is the elastically soft direction

  13. 60Co gamma radiation effect on AlGaN/AlN/GaN HEMT devices

    Institute of Scientific and Technical Information of China (English)

    WANG Yan-Ping; LUO Yin-Hong; WANG Wei; ZHANG Ke-Ying; GUO Hong-Xia; GUO Xiao-Qiang; WANG Yuan-Ming

    2013-01-01

    The testing techniques and experimental methods of the 60Co gamma irradiation effect on AlGaN/AlN/GaN high electron mobility transistors (HEMTs) are established.The degradation of the electrical properties of the device under the actual radiation environment are analyzed theoretically,and studies of the total dose effects of gamma radiation on AlGaN/AlN/GaN HEMTs at three different radiation bias conditions are carried out.The degradation patterns of the main parameters of the AlGaN/AlN/GaN HEMTs at different doses are then investigated,and the device parameters that were sensitive to the gamma radiation induced damage and the total dose level induced device damage are obtained.

  14. Kinetic Monte Carlo of transport processes in Al/AlOx/Au-layers: Impact of defects

    Science.gov (United States)

    Weiler, Benedikt; Haeberle, Tobias; Gagliardi, Alessio; Lugli, Paolo

    2016-09-01

    Ultrathin films of alumina were investigated by a compact kMC-model. Experimental jV-curves from Al/AlOx/Au-junctions with plasma- and thermal-grown AlOx were fitted by simulated ones. We found dominant defects at 2.3-2.5 eV below CBM for AlOx with an effective mass mox ∗= 0.35 m0 and a barrier EB ,A l /A l O x≈2.8 eV in agreement with literature. The parameterization is extended to varying defect levels, defect densities, injection barriers, effective masses and the thickness of AlOx. Thus, dominant charge transport processes and implications on the relevance of defects are derived and AlOx parameters are specified which are detrimental for the operation of devices.

  15. Scattering induced by Al segregation in AlGaN/GaN heterostructures

    International Nuclear Information System (INIS)

    The effect of Al segregation near dislocations on the mobility of two-dimensional electron gas in AlGaN/GaN heterostructure-based high-electron-mobility transistors was investigated. Exponentially varied composition fluctuation was effective in describing Al segregation near dislocations when calculating scattering behavior. Mobility, which was limited by Al segregation surrounding dislocation lines, was calculated to be in the order of 103 cm2/Vs to 106 cm2/Vs. Results indicated that the mobility in AlGaN/GaN heterojunction was enhanced upon the reduction of dislocation density at low temperature. This study contributes to generating higher electron mobility in AlGaN/GaN heterojunctions

  16. Scattering induced by Al segregation in AlGaN/GaN heterostructures

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xiwen; Lu, Yanwu, E-mail: ywlu@bjtu.edu.cn [Department of Physics, Beijing Jiaotong University, Beijing 100044 (China); Ji, Dong [School of Electrical, Computer and Energy Engineering, Arizona State University, Tempe, Arizona 85281 (United States)

    2015-08-17

    The effect of Al segregation near dislocations on the mobility of two-dimensional electron gas in AlGaN/GaN heterostructure-based high-electron-mobility transistors was investigated. Exponentially varied composition fluctuation was effective in describing Al segregation near dislocations when calculating scattering behavior. Mobility, which was limited by Al segregation surrounding dislocation lines, was calculated to be in the order of 10{sup 3} cm{sup 2}/Vs to 10{sup 6} cm{sup 2}/Vs. Results indicated that the mobility in AlGaN/GaN heterojunction was enhanced upon the reduction of dislocation density at low temperature. This study contributes to generating higher electron mobility in AlGaN/GaN heterojunctions.

  17. Determination of Al Composition in Strained AlGaN Layers

    Institute of Scientific and Technical Information of China (English)

    ZHOU Sheng-Qiang; WU Ming-Fang; YAO Shu-De

    2005-01-01

    @@ Alx Ga1-x N/GaN heterostructures are grown on c-sapphire with the Al composition x from 0.2 to 0.4 and thicknesses from 20nm to 30nm. The lattice parameters a and c are determined from 2θ/ω scan. The AlGaN layers are found to be under tensile strain by using x-ray diffraction. Vegard's law induces a large deviation in Al composition determination by only considering the linear relationship between one lattice parameter (a or c) and Al composition. The accurate determination of Al composition is only possible with consideration of both the lattice parameters a and c, by assuming the tetragonal distortion in the AlGaN layer. Additionally, the results obtained from x-ray diffraction are verified by Rutherford backscattering.

  18. Effects of Al(III and Nano-Al13 Species on Malate Dehydrogenase Activity

    Directory of Open Access Journals (Sweden)

    Rong Fu Chen

    2011-05-01

    Full Text Available The effects of different aluminum species on malate dehydrogenase (MDH activity were investigated by monitoring amperometric i-t curves for the oxidation of NADH at low overpotential using a functionalized multi-wall nanotube (MWNT modified glass carbon electrode (GCE. The results showed that Al(III and Al13 can activate the enzymatic activity of MDH, and the activation reaches maximum levels as the Al(III and Al13 concentration increase. Our study also found that the effects of Al(III and Al13 on the activity of MDH depended on the pH value and aluminum speciation. Electrochemical and circular dichroism spectra methods were applied to study the effects of nano-sized aluminum compounds on biomolecules.

  19. 60Co gamma radiation effect on AlGaN//AlN/GaN HEMT devices

    International Nuclear Information System (INIS)

    The testing techniques and experimental methods of the 60Co gamma irradiation effect on AlGaN/AlN/GaN high electron mobility transistors (HEMTs) are established. The degradation of the electrical properties of the device under the actual radiation environment are analyzed theoretically, and studies of the total dose effects of gamma radiation on AlGaN/AlN/GaN HEMTs at three different radiation bias conditions are carried out. The degradation patterns of the main parameters of the AlGaN/AlN/GaN HEMTs at different doses are then investigated, and the device parameters that were sensitive to the gamma radiation induced damage and the total dose level induced device damage are obtained. (authors)

  20. Microscopic Properties of Long-Period Ordering in Al-Rich TiAl Alloys

    Science.gov (United States)

    Hata, S.; Nakano, T.; Kuwano, N.; Itakura, M.; Matsumura, S.; Umakoshi, Y.

    2008-07-01

    The ordering mechanism of long-period superstructures (LPSs) in Al-rich TiAl alloys has been investigated by high-resolution transmission electron microscopy (HRTEM). The LPSs are classified in terms of arrangements of base clusters with different shapes and compositions formed in Ti-rich (002) layers of L10-TiAl matrix: square Ti4Al, fat rhombus Ti3Al, and lean rhombus Ti2Al type clusters. The HRTEM observations revealed that antiphase boundaries of long-range-ordered LPS domains and short-range-ordered microdomains are constructed by various space-filling arrangements of the base clusters. Such a microscopic property characterized by the base clusters and their arrangements is markedly analogous to that of the {left< {{text{1,1/2,0}}} rightrangle } * special-point ordering alloys such as Ni-Mo.

  1. Generation and evolution of nanoscale AlP and Al{sub 13}Fe{sub 4} particles in Al-Fe-P system

    Energy Technology Data Exchange (ETDEWEB)

    Qiao, Huan; Gao, Tong; Zhu, Xiangzhen; Wu, Yuying; Qian, Zhao; Liu, Xiangfa, E-mail: xfliu@sdu.edu.cn

    2015-02-15

    Highlights: • Diffusion and gradual solid reactions between Al and Fe{sub x}P phases in Al-Fe-P alloy were investigated. • Nanoscale AlP clusters are in-situ generated and evolve during the whole process. • This novel Al-Fe-P alloy has an excellent low-temperature refining performance on hypereutectic Al-Si alloy. - Abstract: In this paper, the gradual solid reactions between Al and Fe{sub x}P phases in Al-Fe-P alloy were investigated. The results show that the whole reaction process undergoes four main stages: the diffusion of Al atom, the generation of (Al, Fe, P) intermediate compound, the precipitation of nano AlP and Al{sub 13}Fe{sub 4} clusters and their growth to submicron particles. The microstructure of Fe-P particles evolves from the “egg-type”, the “sponge-type” to the “sesame-cake” structure. AlP and Al{sub 13}Fe{sub 4} nano phases have in-situ generated and evolved during the whole process. The gradual reaction mechanism has been discussed. Furthermore, a novel Al-Fe-P alloy which contains (Al, Fe, P) intermediate compounds and nano AlP particles has been synthesized and its low-temperature refining performance on A390 alloy has also been investigated.

  2. Grain refinement of hypoeutectic Al-Si alloy prepared with ELTA by Al-4B master alloy

    Institute of Scientific and Technical Information of China (English)

    WANG Ming-xing; MENG Xiang-yong; LIU Zhi-yong; LIU Zhong-xia; WENG Yong-gang; SONG Tian-fu; YANG Sheng

    2006-01-01

    Electrolytic low-titanium aluminum (ELTA) was produced by adding TiO2 powder to an industrial aluminum electrolyzer.The grain refining effect of Al-4B master alloy in the hypoeutectic Al-Si alloy prepared by using ELTA was investigated, and compared with those of Al-5Ti, Al-5Ti-1B and Al-4B master alloys in the similar alloy prepared by using pure Al. The results indicate that when Al-4B is added to the melt of the alloy prepared by using ELTA in terms of the Ti/B mass ratio of 5:1, the grain refining effect is better than those of Al-5Ti, Al-5Ti-1B and Al-4B master alloys. Thus, using Al-4B to refine the grain of Al-Si alloys prepared by using ELTA will possibly become a feasible way of obtaining Al-Si alloy with homogeneous and fine microstructure.

  3. In-Situ Synthesis of AlN Powders and Composite AlN Powders with Yttrium Addition

    Institute of Scientific and Technical Information of China (English)

    郑新和; 王群; 林志浪; 李春国; 周美玲

    2002-01-01

    Using Al-Mg and Al-Mg-Y alloys as raw materials and nitrogen as gas reactants, AlN powders and composite AlN powders by in-situ synthesis method were prepared. AlN lumps prepared by the nitriding of Al-Mg and Al-Mg-Y alloys have porous microstructure, which is favorable for pulverization. They have high purity, containing 1.23%(mass fraction) oxygen impurity, and consisted of AlN single phase. The average particle size of AlN powders is 6.78 μm. Composite AlN powders consist of AlN phases and rare earth oxide Y2O3 phase. The distribution of particle size of AlN powders shows two peaks. In view of packing factor, AlN powders with such size distribution can easily be sintered to high density.

  4. Observation of Electronic Shells and Characteristic Products from Mass Abundance Spectra of Al Cluster and Al-C Cluster Anions

    Institute of Scientific and Technical Information of China (English)

    LIU Bing-Chen; ZHAI Hua-Jin; ZHOU Ru-Fang; NI Guo-Quan; XU Zhi-Zhan

    2000-01-01

    Using a laser vaporization/pulsed molecular beam cluster source, Al cluster anions and Al-C mixed cluster anions are produced and recorded by a time of flight mass spectrometer. Mass abundance spectra of the Al cluster anions in the size range from Al2 to Al42 show that Al-13, Al23, Al35, and slightly, Al37 are local maxima, as predicted by the electronic jellium model. Mixed clusters Aln C- and Aln C2 are also shown, among which the most abundant species are Al3 C2 , Al6 C2 , Al7 C- and Al7 C2 in the small size range. The formation mechanism of these products is discussed.

  5. TEM characterization of oxidized AlGaAs/AlAs nonlinear optical waveguides

    OpenAIRE

    Guillotel, E; Langlois, C.; Ghiglieno, F.; Leo, G.; Ricolleau, C.

    2010-01-01

    Abstract The internal interfaces of multilayer Al x Ga 1-x As/AlAs nonlinear optical waveguides are investigated by high-angle annular-dark-field and energy-filtered scanning transmission electron microscopy, before and after partial wet oxidation of AlAs layers. Via a simple phenomenological model, the corresponding roughness parameters allow predicting the scattering-induced waveguide optical losses, which are in reasonable agreement with the experimental value of 0.5 cm -1. We also find...

  6. Two-Phase (TiAl+TiCrAl) Coating Alloys for Titanium Aluminides

    Science.gov (United States)

    Brady, Michael P. (Inventor); Smialek, James L. (Inventor); Brindley, William J. (Inventor)

    1998-01-01

    A coating for protecting titanium aluminide alloys, including the TiAl gamma + Ti3Al (alpha(sub 2)) class, from oxidative attack and interstitial embrittlement at temperatures up to at least 1000 C. is disclosed. This protective coating consists essentially of titanium, aluminum. and chromium in the following approximate atomic ratio: Ti(41.5-34.5)Al(49-53)Cr(9.5-12.5)

  7. Modified Mechanism of Eutectic Silicon in Al2O3/Al-Si Alloy

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Al2O3/Al-Si alloy composite was manufactured by squeeze casting. The morphology of the eutectic silicon in the composite was observed by scanning electronic microscope (SEM), and the modified mechanism of eutectic silicon in the composite was approached. The alumina fiber in the composite can trigger twin during the growth of Al-Si eutectic and lead to the modification of eutectic silicon near the fiber.

  8. Melt Processing and Characterization of Al-SiC Nanocomposite, Al, and Mg Foam Materials

    OpenAIRE

    Ahmed M. Nabawy; Khalil Abdelrazek Khalil; Al-Ahmari, Abdulrahman M.; Sherif, El-Sayed M.

    2016-01-01

    In the present work, metallic foams of Al, Mg and an Al-SiC nanocomposite (MMNC) have been fabricated using a new manufacturing technique by employing melt infiltration assisted with an electromagnetic force. The aim of this investigation was to study and to develop a reliable manufacturing technique consisting of different types of metallic foams. In this technique, an electromagnetic force was used to assist the infiltration of Al-SiC slurry and of pure liquid metal into a leachable pattern...

  9. Effect of the interface in laminated composites of Al-1100 and Al-2024

    International Nuclear Information System (INIS)

    Laminated composites consisting of alternating layers of Al-1100 and Al-2024 were produced by hot rolling, with 45% Al-2024 volume fraction. These composites were subjected to cyclic thermal treatment (various numbers of cycles) and to isothermal treatment (various numbers of cycles) and to isothermal treatment (at peak temperature and for times equivalent to those of the thermal cycles. Microhardness, tensile and fatigue crack arrester modes) were studied in the initial state and after treatments. (E.G.)

  10. APOYO PÚBLICO A LA ENERGÍA EÓLICA EN ESPAÑA

    Directory of Open Access Journals (Sweden)

    Masao Javier López Sako

    2009-01-01

    Full Text Available El presente trabajo pretende describir y valorar brevemente el régimen jurídico-económico de la energía eólica en España. Nos referimos en concreto al sistema de apoyo público a la producción de electricidad a partir de las energías renovables mediante el sistema denominado "de primas". El fijarnos en la energía eólica en particular se justifica por la sencilla razón de que España ocupa el tercer puesto a nivel mundial en potencia eólica instalada, después de Alemania y EE. UU, hecho que va unido a la circunstancia de la importancia a todos los niveles que ha cobrado este sector en España. Por otra parte, conviene recordar que el uso de energía (su producción y consumo es el principal factor de emisiones de gases de efecto invernadero y las energías renovables suponen una pieza clave en la lucha contra el cambio climático. Y también que España se encuentra entre los países más alejados del cumplimiento del Protocolo de Kyoto. Desde esta perspectiva, el protagonismo de la energía eólica es también patente: en nuestro país, dentro de las energías renovables, la energía eólica en particular es la que más está aportando al mix de generación eléctrica, convirtiéndose en la contribución más segura a dicha lucha ambiental de carácter global. En este sentido, la proporción de energía eléctrica aportada por la eólica se encuentra -con más del 11% en 2008- en la segunda posición mundial; aquí España solo es superada por Dinamarca. Es importante, por tanto, mantener una buena política de fomento de esta tecnología renovable.

  11. Growth of CdTe: Al films; Crecimiento de peliculas de CdTe: Al

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez A, M.; Zapata T, M. [CICATA-IPN, 89600 Altamira, Tamaulipas (Mexico); Melendez L, M. [CINVESTAV-IPN, A.P. 14-740, 07000 Mexico D.F. (Mexico); Pena, J.L. [CINVESTAV-IPN, A.P. 73 Cordemex, 97310 Merida, Yucatan (Mexico)

    2006-07-01

    CdTe: AI films were grown by the close space vapor transport technique combined with free evaporation (CSVT-FE). The Aluminum (Al) evaporation was made by two kinds of sources: one made of graphite and the other of tantalum. The films were deposited on glass substrates. The Al source temperature was varied maintaining the CdTe source temperature fixed as well as the substrate temperature. The films were characterized by x-ray energy dispersive analysis (EDAX), x-ray diffraction and optical transmission. The results showed for the films grown with the graphite source for Al evaporation, the Al did not incorporate in the CdTe matrix, at least to the level of EDAX sensitivity; they maintained the same crystal structure and band gap. For the samples grown with the tantalum source, we were able to incorporate the Al. The x-ray diffraction patterns show that the films have a crystal structure that depends on Al concentration. They were cubic up to 2.16 at. % Al concentration; for 19.65 at. % we found a mixed phase; for Al concentration higher than 21 at. % the films were amorphous. For samples with cubic structure it was found that the lattice parameter decreases and the band gap increases with Al concentration. (Author)

  12. Strain Rates and Grain Growth in Al 5754 and Al 6061 Friction Stir Spot Welds

    Science.gov (United States)

    Gerlich, A.; Yamamoto, M.; North, T. H.

    2007-06-01

    The stir zone temperature and microstructures are compared in friction stir spot welds produced in Al 5754 and Al 6061 alloys. Electron backscattered diffraction was used to determine the relationship between tool rotation speed during welding and final stir zone grain size. Comparison of the grain sizes in rapidly quenched welds with those in air-cooled joints confirmed that grain growth occurred only in Al 6061 spot welds. There was no evidence of abnormal grain growth in the stir zones of Al 6061 welds; the final grain size could be represented using an Arrhenius equation. The strain rates during welding were determined by incorporating the stir zone temperature and average subgrain sizes in quenched spot welds in the Zener-Hollomon relation. When the tool rotation speed increased from 750 to 3000 RPM, the strain rate values ranged from 180 to 497 s-1 in Al 5754 spot welds and from 55 to 395 s-1 in Al 6061 spot welds. It is suggested that a no-slip boundary condition may be appropriate during numerical modeling of Al 5754 and 6061 friction stir spot welding. This is not the case during Al 7075, Al 2024, and Mg-alloy AZ91 spot welding because spontaneous melting facilitates slippage at the tool contact interface.

  13. Microstructure and thermal stability of mechanically alloyed Al3Ti/Al alloy

    Institute of Scientific and Technical Information of China (English)

    林建国; 魏浩岩; 黄正

    2001-01-01

    The microstructure stability of Al3Ti/Al alloy prepared by mechanical alloying (MA) was investigated in the simulating environment in which they may be used. The results show that the MA alloy possesses fine microstructure (the grain size is about 0.5  μm). After cycling loaded followed by heat exposure at 350  ℃ for 24  h, no microstructure coarsening of the alloy occurred, which means that the Al3Ti/Al alloy behaves good microstructure stability at high temperature. The compression yield strength of the alloy reaches up to 247  MPa at 350  ℃.

  14. AlN/IDT/AlN/Sapphire SAW Heterostructure for High-Temperature Applications.

    Science.gov (United States)

    Legrani, Ouarda; Aubert, Thierry; Elmazria, Omar; Bartasyte, Ausrine; Nicolay, Pascal; Talbi, Abdelkrim; Boulet, Pascal; Ghanbaja, Jaafar; Mangin, Denis

    2016-06-01

    Recent studies have evidenced that Pt/AlN/Sapphire surface acoustic wave (SAW) devices are promising for high-temperature high-frequency applications. However, they cannot be used above 700°C in air atmosphere as the Pt interdigital transducers (IDTs) agglomerate and the AlN layer oxidizes in such conditions. In this paper, we explore the possibility to use an AlN protective overlayer to concurrently hinder these phenomena. To do so, AlN/IDT/AlN/Sapphire heterostructures undergo successive annealing steps from 800°C to 1000°C in air atmosphere. The impact of each step on the morphology, microstructure, and phase composition of AlN and Pt films is evaluated using optical microscopy, scanning and transmission electron microscopy (SEM and TEM), X-ray diffraction (XRD), and secondary ion mass spectroscopy (SIMS). Finally, acoustical performance at room temperature of both protected and unprotected SAW devices are compared, as well as the effects of annealing on these performance. These investigations show that the use of an overlayer is one possible solution to strongly hinder the Pt IDTs agglomeration up to 1000°C. Moreover, AlN/IDT/AlN/Sapphire SAW heterostructures show promising performances in terms of stability up to 800°C. At higher temperatures, the oxidation of AlN is more intense and makes it inappropriate to be used as a protective layer. PMID:27076407

  15. Microstructure and mechanical properties of Al2O3/TiAl composite

    Institute of Scientific and Technical Information of China (English)

    AI Tao-tao; WANG Fen; ZHU Jian-feng

    2006-01-01

    Al2O3/TiAl composites were fabricated by PAXD (pressure-assisted exothermic dispersion) method. The effects of Nb2O5 content on the microstructure and mechanical properties of the composites were investigated. The results show that the ultimate phases of the composite consist of TiAl, Ti3Al, Al2O3 and a small amount of NbAl3. SEM reveals that a submicron γ+(α2/γ) dual phases structure can be presented after sintered at 1 200 ℃. Furthermore, with the increase of Nb2O5 content, the ratio of TiAl to Ti3Al phase decreases correspondingly, the grains of the composites are remarkably refined, and the produced Al2O3 particles are uniformly dispersed. When 6% Nb2O5 is added, the composite has the best comprehensive properties. It exhibits a Vickers hardness of 4.77 GPa and a bending strength of 642 MPa. Grain-refinement and dispersion-strengthening are the main strengthening mechanisms.

  16. Coating of a layer of Au on Al13 : The findings of icosahedral Al@Al12Au20- and Al12Au202- fullerenes using ab initio pseudopotential calculations

    Science.gov (United States)

    Kumar, Vijay

    2009-02-01

    We report results of ab initio pseudopotential calculations on the nanocoating of gold on an icosahedral Al13 cluster and the findings of icosahedrally symmetric endohedral Al@Al12Au20- and empty cage Al12Au202- compound fullerenes formed of metal atoms. Twelve Al atoms cap the pentagonal faces of a dodecahedral Au20 cage in which each Au atom has three Al atoms and three Au atoms as nearest neighbors. Mixing of Al13 and Au20 magic clusters leads to a large heat of formation of 0.55 eV/atom and high stability of the Al@Al12Au20 compound fullerene. The binding energies of Al12Au20 and Al@Al12Au20 are 3.017 and 3.007 eV/atom, respectively, which are much larger than 2.457 eV/atom for Au32 fullerene, leading to the possibility of their high abundance.

  17. Epistemologi Penafsiran Ilmiah al-Qur’an

    Directory of Open Access Journals (Sweden)

    Sujiat Zubaidi Saleh

    2011-04-01

    Full Text Available The main objective in interpretating al-Qur’an is to explain the will of God and the operationalization of the will in the field of faith, laws, or ethics. At the phase of Islamic civilization, when the linguistic and philosophy science codified, raises the various method (manhaj, and interpretation streams (ittijahat, exegesis school (madzhab of al-Qur’an. In addition, also found in various shades of interpretation such as: fiqhi, kalami, balaghi, and isyari/ sufi, even philosophical. It was also discovered methods of tafsir ‘ilmi oriented to the utilization of the discovering science in order to prove the truth of scientific fact. The last pattern was ignited pro and contra among scholars and mufassir. As we know that alQur’an was not descended in the condition of cultural vacuum but it is a form of dialectics and the response to the condition and social situation, politic, and religion. This is relevant to the characteristics of al-Qur’an which can be applied throughout the periods. As we understood that interpretation is one of reflections of thought and civilization products. It always developed and influenced by the dynamics of human civilization, so in its development, science and al-Qur’an can be brought together in dialogue, although with some prerequisites specified interpretation.

  18. Direct laser cooling Al+ ions optical clocks

    CERN Document Server

    Zhang, J; Luo, J; Lu, Z H

    2016-01-01

    Al$^+$ ions optical clock is a very promising optical frequency standard candidate due to its extremely small blackbody radiation shift. It has been successfully demonstrated with indirect cooled, quantum-logic-based spectroscopy technique. Its accuracy is limited by second-order Doppler shift, and its stability is limited by the number of ions that can be probed in quantum logic processing. We propose a direct laser cooling scheme of Al$^+$ ions optical clocks where both the stability and accuracy of the clocks are greatly improved. In the proposed scheme, two Al$^+$ ions traps are utilized. The first trap is used to trap a large number of Al$^+$ ions to improve the stability of the clock laser, while the second trap is used to trap a single Al$^+$ ions to provide the ultimate accuracy. Both traps are cooled with a continuous wave 167 nm laser. The expected clock laser stability can reach $9.0\\times10^{-17}/\\sqrt{\\tau}$. For the second trap, in addition to 167 nm laser Doppler cooling, a second stage pulsed ...

  19. Kerja Perspektif Al-Qur'an

    Directory of Open Access Journals (Sweden)

    Ahmad Munir

    2011-05-01

    Full Text Available The moslem ethics of life is based on movement as ex­pressed in certain terms like al-sharī’ah, al-tarīqah, al-sirāt, al-sabīl and al-manhaj, that make sense of way and teachings to achieve good life. Islam obliges and gives appreciation of the achievements of Mus­lims. The Qur’an uses several terms to refer to such work; ‘charity, kasb, juhd, ibtighâ’, sa ’yu and su ’âl. From this concept, the Qur’an considers work as nob­le, while begging is despicable. Work means thankful to God for the potential He bestows. The Qur’an promotes work not only because it is the way to achieve the wealth, but also because it possesses the its sacred value for the benefit of fulfilling livelihood. Therefore the work should also be done based on ethical values .

  20. ‘Uluww al-Isnad dalam Periwayatan Hadis Abu Muhammad al-Husain bin Mas‘ud al-Baghawi

    Directory of Open Access Journals (Sweden)

    Romlah Abubakar Askar

    2016-05-01

    Full Text Available Abu Muhammad al-Husayn Ibnu Mas’ud al-Baghawi (450-516H was one of the leading scholars in Tafsir (Quran exegesis, hadith (prophetic tradition, and fiqh (Islamic legal jurisprudence in his era. He was categorized as muta’akhirūn (scholars who came later on and was instrumental in the development of these three disciplines. In the field of exegesis, he was among the scholars who used al-Ma’tsūr, (commentary stylist, relying on the verses of the Qur’an, hadith, and the statements from the followers of the tabi’īn (the followers of the followers. This can be found in his recorded work Ma’ālim al Tanzīl. In the field of hadith, he preserved the narration method and presenting a new approach by merging some patterns of hadith narration from several books of hadith in his work known as ṭarīqah al-Jam’u (combination [amalgamation] method. This pattern will not occur unless there is the existence of other transmission lines as a second chain of narration used to produce ‘uluww al-Isnād (the noble sanad or nuzūl al-Isnād (descent sanad. It is recorded in his works: al-Jam’u baina al-Ṣaḥīḥain, Sharḥ al-Sunnah and Maṣābiḥ al-Sunnah. In the field of Jurisprudence, he was amongst those mujtahidin from the Shafiee school of thought, recorded in his Majmū’ ‘al-Fatāwā, al-Kifāyah fī al-Furū’ and Kitāb al-Tahdzīb. This paper aims to examine one of al-Baghawi’s skills in sanad collection which is the uluww al-isnād and nuzūl al-isnād, recorded from his two works Ma’ālim al-Tanzīl and Syarḥ al-Sunnah. The quantitative, qualitative and comparative approach has been used in this study to give an authentic description of the terms ‘uluww al-isnād, nuzūl al-isnād from al-Baghawi. Studies have found there are many examples of uluww al-Isnād and nuzūl al-isnāds contained in the patterns of al-Baghawi’s chain of narration towards the Ṣaḥīḥayn of al-Bukhari and Muslim as the mustakhrij

  1. MOSQUE ARCHITECTURE AS A SUSTAINABLE BUILDING IN URBAN (Case Study: Al Markas Al Islamic Mosque Makassar

    Directory of Open Access Journals (Sweden)

    Imriyanti Imriyanti

    2014-02-01

    Full Text Available Abstract Mosque Architecture is a part of Islamic architecture. Mosque should be fused with elements of nature because its function as a place to pray to God who created the universe. Al Markas Al Islamic Makassar mosque is used as a center of Islamic aspirations of the people and the government to accommodate all the activities of moslems in Makassar. Through this function, the provision of Al Markas Al Islamic mosque began from the desire of Islamic societies in Makassar, which wants the Islamic center to be equipped with facilities and infrastructure as well as architectural, monumental buildings and structures that can be last for hundreds of years (continuous, blend with the environment, and also can be used by the public. Having regard to the function of a mosque especially at the Al Markas Al Islamic Makassar mosque, then the problem that arise is how the Al Markas Al Islamic mosque can be survived/sustainable  in order  to function  as a place  of worship  and  as a center  of Islam.  This research  is a descriptive qualitative research that is trying to generate data in the form of systematic and accurate picture of the object of study. The sustaiprophetlity  of Al Markas AL Islamic mosque can be known through the concept of Islam  in accordance with the view of Islam as well as the sustaiprophetlity of the buildings that seen in the spatial pattern of the mosque, appearance, natural lighting, natural ventilation, and user behavior of the mosque. Keywords: mosque architecture, sustaiprophetlity, view of Islam     Abstrak Arsitektur masjid merupakan bagian dari arsitektur Islam. Bangunan masjid sebaiknya dapat menyatu dengan unsur alam karena masjid difungsikan sebagai wadah dalam bersujud/sembahyang  kepada Allah SWT yang menciptakan alam semesta ini. Masjid Al Markas Al Islamic Makassar merupakan kompleks kegiatan Islam yang digunakan sebagai pusat aspirasi masyarakat  dan pemerintahan  yang dapat menampung

  2. Melting Transition of Small Aluminium Clusters Al11-20

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wei; ZHANG Feng-Shou; ZHU Zhi-Yuan

    2007-01-01

    Heat capacities of small aluminium clusters Al11-20 are investigated using MD simulation with empirical manybody Gupta potential. The heat capacities of some clusters Al11, Al12, Al13 and Al19 show well-defined peaks while the heat capacities of Al15-18 indicate a gradual melting transition. The spectra of isomers obtained by quenches along the MD trajectory give good interpretation for those results.

  3. Instability of TiC and TiAl3 compounds in Al-10Mg and Al-5Cu alloys by addition of Al-Ti-C master alloy

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The performance of Al-Ti-C master alloy in refining Al-10Mg and A1-5Cu alloys was studied by using electron probe micro-analyzer (EPMA) and X-ray diffractometer (XRD) analysis.The results indicate that there are obvious fading phenomena in both Al-10Mg and Al-5Cu alloys with the addition of Al-5Ti-0.4C refiner which contains TiC and TiAl3 compounds.Mg element has no influence on the stability of TiC and TiAl3, while TiC particles in Al-10Mg alloy react with Al to form Al4C3 particles, resulting in the refinement fading.However, TiC particles are relatively stable in Al-5Cu alloy, while TiAl3 phase reacts with Al2Cu to produce a new phase Ti(Al, Cu)2, which is responsible for the refinement fading in Al-5Cu alloy.These indicate that the refinement fading will not occur only when both the TiC particles and TiAl3 compound of Al-Ti-C refiner are stable in Al alloys.

  4. Al- Khwarizmi and axiomatic foundation of algebra

    International Nuclear Information System (INIS)

    This paper intends to investigate the axiomatic foundations of algebra, as they were presented in the book of algebra of al-Khwarizmi (9 th century), and as they were developed in many subsequent Arabic works. The paper gives also a description of algebra evolution towards a discipline independent ofgeometry and arithmetic: the two disciplines whosemarriage had led to its birth.By an in depth reading of some details in the text of al Khwarizmi , we concluded that this mathematician intended to lay down the axiomatic foundations of that new discipline. His resort to arithmetical and geometrical means was a way of making his theory more accessible. He used them to justify the axioms: those that were not explicitly introduced per se, and those that were remained implicit. The paper also relies on some unedited writingsof al-Khwarizmi's successors, which could shedlight on the ways they used to consolidate the foundations of algebra and improve its methods. (author)

  5. Moessbauer studies on Al-Co ferrites

    International Nuclear Information System (INIS)

    Moessbauer spectroscopy studies have been performed on the spinel CoAlxFe2-xO4 (.2≤x≤1.7) in the temperature range 77-750 K using either a liquid nitrogen bath cryostat or a furnace. The samples are magnetic at 77 K giving spectra that have magnetic sextets coexisting with a central line which increases in population with the Al-content indicating relaxation effects. The data shows that Al possesses no preference to either tetrahedral or octahedral sites of the ferrite over the whole range of concentration. The Moessbauer hyperfine interaction parameters and magnetic transition temperatures were determined. As expected the hyperfine field and Curie temperature decrease when the Al-content increases. (orig.)

  6. Thermal Properties of Al-50%Si Alloys

    Institute of Scientific and Technical Information of China (English)

    Akio Nishimoto; Katsuya Akamatsu; Kazuyoshi Nakao; Kazuo Ichii

    2004-01-01

    In order to prepare a hypereutectic Al-Si alloy with low coefficients of thermal expansion (CTE), Al-50was produced by powder metallurgy (P/M) and ingot metallurgy (I/M). P/M specimen was prepared by mechanical alloying(MA) and pulsed electric-current sintering (PECS). The microstructures of specimens were characterized by optical microscopy and scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectroscopy (EDS). Vickers microhardness and CTE measurements were performed. The grains in the P/M specimen were refined with increasing MA time. Primary Si and eutectic Si in the I/M specimen were remarkably refined by adding minute amounts of Sr. The CTE of P/M and I/M specimens were estimated as 7.8×10-6 and 10.7×10-6, respectively. These values were as same as a CTE of Al2O3 ceramics.

  7. Autologous Stem Cell Transplant for AL Amyloidosis

    Directory of Open Access Journals (Sweden)

    Vivek Roy

    2012-01-01

    Full Text Available AL amyloidosis is caused by clonal plasma cells that produce immunoglobulin light chains which misfold and get deposited as amyloid fibrils. Therapy directed against the plasma cell clone leads to clinical benefit. Melphalan and corticosteroids have been the mainstay of treatment for a number of years and the recent availability of other effective agents (IMiDs and proteasome inhibitors has increased treatment options. Autologous stem cell transplant (ASCT has been used in the treatment of AL amyloidosis for many years. It is associated with high rates of hematologic response and improvement in organ function. However, transplant carries considerable risks. Careful patient selection is important to minimize transplant related morbidity and mortality and ensure optimal patient outcomes. As newer more affective therapies become available the role and timing of ASCT in the overall treatment strategy of AL amyloidosis will need to be continually reassessed.

  8. Iluminación de patios mediante el diseño de muros cortina reflectantes de geometría variable

    OpenAIRE

    BAU PALAU, PALOMA

    2011-01-01

    El objetivo principal del proyecto es la iluminación de zonas sombrías, como patios interiores, por reflexión de luz natural mediante el diseño de muros cortina formados de piezas modulares de geometría variable, que iluminan mediante reflexión de luz solar, aportando también reflejos de colores, iluminación artificial, vegetación vertical, y proyección de imágenes Bau Palau, P. (2011). Iluminación de patios mediante el diseño de muros cortina reflectantes de geometría variable. http://hdl...

  9. MgAl2O4–-Al2O3 solid solution interaction: mathematical framework and phase separation of -Al2O3 at high temperature

    Indian Academy of Sciences (India)

    Soumen Pal; A K Bandyopadhyay; S Mukherjee; B N Samaddar; P G Pal

    2011-07-01

    Although existence of MgAl2O4–-Al2O3 solid solution has been reported in the past, the detailed interactions have not been explored completely. For the first time, we report here a mathematical framework for the detailed solid solution interactions of -Al2O3 in MgAl2O4 (spinel). To investigate the solid solubility of -Al2O3 in MgAl2O4, Mg–Al spinel (MgO–Al2O3; = 1, 1.5, 3, 4.5 and an arbitrary high value 30) precursors have been heat treated at 1000°C. Presence of only non-stoichiometric MgAl2O4 phase up to = 4.5 at 1000°C indicates that alumina (as -Al2O3) present beyond stoichiometry gets completely accommodated in MgAl2O4 in the form of solid solution. → alumina phase transformation and its subsequent separation from MgAl2O4 has been observed in the Mg–Al spinel powders ( > 1) when the 1000°C heat treated materials are calcined at 1200°C. In the mathematical framework, unit cell of MgAl2O4 (Mg8Al16O32) has been considered for the solid solution interactions (substitution of Mg2+ ions by Al3+ ions) with -Al2O3. It is suggested that combination of unit cells of MgAl2O4 takes part in the interactions when > 5 (MgO–Al2O3).

  10. Kritik Terhadap Pemikiran Tasawuf Al-Raniri

    Directory of Open Access Journals (Sweden)

    Syaifan Nur

    2013-12-01

    Full Text Available Abstract : Al-Raniri is often positioned by some scholars as “superior” figure, which is contrasted to Hamzah Fansuri and Syamsuddin Sumaterani, and that is why they predicate him as one of pioneer of Islamic reformer in Malay- Indonesian archipelago. Anti-wujūdiyyah Sufism campaign by al-Raniri quite successful to some extent to amputate the rate of development of philosophical Sufism was brought by Fansuri and Sumaterani in the one hand, and strike off the nature of moral Sufism in the other, redeemed by bloodshed. This article discussed the “superiority” of al-Raniri’s thought of Sufism, viewed from a broader spectrum, either in relation to problems of faith or theology and politics surrounding the circumstance of his time.Keywords : Philosophical tasawuf, neo-sufism, panteism, tajalli, God’s attributeAbstrak : Al-Raniri oleh banyak kalangan seringkali diposisikan sebagai tokoh “superior” yang diperlawankan dengan Hamzah Fansuri dan Syamsuddin Sumaterani, dan itu sebabnya para ahli memberinya predikat sebagai seorang pelopor pembaru (mujaddid Islam di Nusantara. Anti tasawuf wujūdiyyah yang dikampanyekan oleh al-Raniri cukup berhasil mengamputasi laju perkembangan tasawuf falsafi yang dibawa oleh Fansuri dan Sumaterani di satu sisi, dan melancarkan laju corak tasawuf akhlaki di sisi lain, yang ditebus dengan cara pertumpahan darah. Tulisan ini mendiskusikan “superioritas” pemikiran tasawuf al-Raniri tersebut, dilihat dari spektrum yang lebih luas, baik menyangkut persoalan keyakinan atau teologi maupun politik yang mengitari situasi zamannya.Kata kunci : Tasawuf falsafi , neo-sufisme, panteisme, tajalli, sifat Tuhan

  11. Diffusion AlSi-MeCrAlY coatings obtained on intermetallic γ-TiAl phase

    Directory of Open Access Journals (Sweden)

    M. Góral

    2012-12-01

    Full Text Available Purpose: The development of new protective coatings for TiAl intermetallics was conducted. The MeCrAlYAlSi slurry was used with different amount of aluminium-silicon powder in the binder.Design/methodology/approach: The slurry consisting of aluminium and silicon powder with the addition of MeCrAlY powder were used during the procedure. The inorganic solution made from chromic and phosphoric acid was applied as a binder. The preliminary research of microstructure of obtained coatings was conducted.Findings: The obtained coating consisting of 3 or 4 zones (depending on chemical composition of the slurry was obtained during the annealing process (950°C/4h.Research limitations/implications: The research results revealed the possibility of obtaining coatings with complex phase and chemical composition.Practical implications: Many problems connected with sedimentation of heavier MeCrAlY powder were observed.Originality/value: The copletele new technologies was described in article

  12. Fabrication of Al-Al3Ti/Ti3Al Functionally Graded Materials under a Centrifugal Force

    Directory of Open Access Journals (Sweden)

    Yoshimi Watanabe

    2010-09-01

    Full Text Available Fabrication of Al-Al3Ti functionally graded materials (FGMs under the centrifugal force has recently attracted some attention. The controlled compositional gradient of the fabricated FGMs, the low cost of the process, and the good mold filling, are the main advantages of the centrifugal method (CM. Using the conventional CM techniques such as the centrifugal solid-particle method and centrifugal in-situ method, FGMs rings with gradually distributed properties could be achieved. As a more practical choice, the centrifugal mixed-powder method (CMPM was recently proposed to obtain FGMs containing nano-particles selectively dispersed in the outer surface of the fabricated parts. However, if a control of the particles morphology, compound formulas or sizes, is desired, another CM technique is favored. As a development of CMPM, our novel reaction centrifugal mixed-powder method (RCMPM has been presented. Using RCMPM, Al‑Al3Ti/Ti3Al FGMs with good surface properties and temperature controlled compositional gradient could be achieved. In this short review, this novel method will be discussed in detail and the effect of RCMPM processing temperature on the reinforcement particles morphology, size and distribution through the fabricated samples, will be reviewed.

  13. Total energy, equation of state and bulk modulus of AlP, AlAs and AlSb semiconductors

    Indian Academy of Sciences (India)

    A R Jivani; H J Trivedi; P J Gajjar; A R Jani

    2005-01-01

    Recently proposed model potential which combines both linear and quadratic types of interactions is employed for the investigation of some properties like the total energy, equation of state and bulk modulus of AlP, AlAs and AlSb semiconductor compounds using higher-order perturbation theory. The model potential parameter is determined using zero pressure condition. The ratio of the covalent bonding term E cov to the second-order term 2 is 6.77% to 11.85% which shows that contribution from higher order terms are important for zinc-blende-type crystals. The calculated numerical results of the total energy, energy band gap at Jones-zone face and bulk modulus of these compounds are in good agreement with the experimental data and found much better than other such theoretical findings. We have also studied pressure–volume relations of these compounds. The present study is carried out using six different screening functions along with latest screening function proposed by Sarkar et al. It is found from the present study that effect of exchange and correlation is clearly distinguishable.

  14. Simulations of the premelting of Al(110)

    DEFF Research Database (Denmark)

    Stoltze, Per

    1990-01-01

    The premelting of Al(110) is studied by molecular dynamics simulations using the potential for Al derived from effective medium theory. We find a progressive disordering of the surface region as the bulk melting point is approached. This disorder is mediated by the formation of adatom–vacancy pairs....... Based on the calculated radial distribution function and the analytical expression for the energy, it is demonstrated that the thermodynamics of disorder and melting is reflected in the single particle properties by a decrease in the number of nearest neighbors. The Debye temperature for the surface...

  15. Quadrupole scattering in PrAl2

    Science.gov (United States)

    Sablik, M. J.; Pureur, P.; Creuzet, G.; Fert, A.; Levy, P. M.

    1983-10-01

    We derive the spontaneous anisotropy of the resistivity of the ferromagnetic compound PrAl2 from magnetoresistance measurements on a single crystal of PrAl2. We ascribe this spontaneous anisotropy of the resistivity to scattering of the conduction electrons by the thermal quadrupole disorder and we account for our experimental results by using the theoretical model previously developed by us. We find that quadrupole scattering gives a very important contribution to the total magnetic disorder (spin and quadrupole) resistivity but that only a small part of this quadrupole contribution is anisotropic.

  16. Aspectos biopsicosociales asociados al embarazo adolescente

    OpenAIRE

    Regina Cogollo Jiménez

    2012-01-01

    Introducción: El embarazo en la adolescencia, es un evento inesperado, sorpresivo. Este artículo establece la importancia de identificar los aspectos biopsicosociales asociados al embarazo adolescente en las embarazadas asistentes al programa de Control Prenatal de una Empresa Social del Estado de nivel 1 en Montería en 2009, para comprender las actitudes y los comportamientos asociados a esta etapa tan temprana. Materiales y Métodos: Es un estudio descriptivo, cuantitativo, de corte transver...

  17. Amyotrofisen lateraaliskleroosin (ALS) fysioterapia : Systemaattinen kirjallisuuskatsaus

    OpenAIRE

    Finne, Ida

    2015-01-01

    Amyotrofinen lateraaliskleroosi eli ALS on harvinainen motoneuronisairaus, jonka ominaispiirteenä on selkäytimen, aivorungon ja aivokuoren motoneuroneiden etenevä degeneraatio ja tuhoutuminen. Tähän parantumattomaan sairauteen sairastuu Suomessa vuosittain noin 120–150 henkilöä. Keskimääräinen sairastumisikä on noin 60 vuotta ja elinikä diagnoosin saamisen jälkeen on noin 3 - 5 vuotta. Fysioterapia on tärkeä osa ALS-potilaan hoitoa ja kuntoutusta. Fysioterapian vaikutut-tavuutta on tästä ...

  18. Recent research highlights from the ALS OML

    OpenAIRE

    Yashchuk, Valeriy V.

    2013-01-01

    The main mission of the Optical Metrology Laboratory (OML) at the Advanced Light Source (ALS) is to ensure state-of-the-art performance of beamline optics. New beamlines and instruments laid out in the ALS strategic plan as well as the plan for New Generation Light Source (NGLS) facility all involve increasingly complex optical systems that need ultra-high precision optics to achieve the specifications and goals of their state-of-the art research programs. In order to manufacture, measure, tu...

  19. Semantische Merkmale als Mittel der Textkonstitution

    Directory of Open Access Journals (Sweden)

    Stojan Bračič

    2008-12-01

    Full Text Available Im folgenden Beitrag sollen semantische Relationen unter die Lupe genommen werden, die im text dazu beitragen, dass einzelne Textkomponenten miteinander verknüpft werden. Dabei geht es hauptsächlich um Relationen, die nicht satzthematisch sind - diese sind nämlich als textuelle Koreferenzketten ausreichend untersucht worden (vgl. u.a. Bračič/Fix/Greule 2007 - sondern um jene Relationen, die als Prädikationen einzelner textgrammatischer Einheiten (Sätze vorkommen und ebenfalls gewisse geordnete Strukturierungen aufweisen.

  20. Introducción al derecho

    OpenAIRE

    Collado Luis, Santiago

    2012-01-01

    Manual de la asignatura introducción al derecho. Nivel educativo: Grado El origen de este texto –materiales docentes- que lleva por título “Introducción al Derecho” ha sido escrito respondiendo a una estricta necesidad docente y por tanto necesariamente pedagógica. En efecto, era totalmente necesario que los alumnos, del Grado de Administración y Dirección de Empresas y otras titulaciones no jurídicas, contasen con un texto para facilitar el estudio de las principales categorías conceptual...

  1. Magnetic Properties of NdAl2

    DEFF Research Database (Denmark)

    Bak, P.

    1974-01-01

    The magnetic properties of NdAl2 are calculated using a Hamiltonian including crystal-field and isotropic exchange interaction terms. A two-dimensional mean-field theory is evaluated to calculate single-crystal magnetization curves. It is shown that the magnetic properties can be understood using...... the crystal-field parameters derived from the magnetic exciton spectrum measured by Houmann et al. by means of inelastic neutron scattering. The combined lambda -Schottky anomaly in the heat capacity is explained. No additional parameters are introduced....

  2. Metamagnetism in Ce(Ga,Al)2

    Indian Academy of Sciences (India)

    K G Suresh; S Radha; A K Nigam

    2002-05-01

    Effect of Al substitution on the magnetic properties of Ce(Ga1-Al)2 ( = 0, 0.1 and 0.5) system has been studied. The magnetic state of CeGa2 is found to be FM with a C of 8 K, whereas the compounds with =0.1 and 0.5 are AFM and possess N of about 9 K. These two compounds undergo metamagnetic transition and the critical fields are about 1.2 T and 0.5 T, respectively at 2 K. These variations are explained on the basis of helical spin structure in these compounds.

  3. Melting, Processing, and Properties of Disordered Fe-Al and Fe-Al-C Based Alloys

    Science.gov (United States)

    Satya Prasad, V. V.; Khaple, Shivkumar; Baligidad, R. G.

    2014-09-01

    This article presents a part of the research work conducted in our laboratory to develop lightweight steels based on Fe-Al alloys containing 7 wt.% and 9 wt.% aluminum for construction of advanced lightweight ground transportation systems, such as automotive vehicles and heavy-haul truck, and for civil engineering construction, such as bridges, tunnels, and buildings. The melting and casting of sound, porosity-free ingots of Fe-Al-based alloys was accomplished by a newly developed cost-effective technique. The technique consists of using a special flux cover and proprietary charging schedule during air induction melting. These alloys were also produced using a vacuum induction melting (VIM) process for comparison purposes. The effect of aluminum (7 wt.% and 9 wt.%) on melting, processing, and properties of disordered solid solution Fe-Al alloys has been studied in detail. Fe-7 wt.% Al alloy could be produced using air induction melting with a flux cover with the properties comparable to the alloy produced through the VIM route. This material could be further processed through hot and cold working to produce sheets and thin foils. The cold-rolled and annealed sheet exhibited excellent room-temperature ductility. The role of carbon in Fe-7 wt.% Al alloys has also been examined. The results indicate that Fe-Al and Fe-Al-C alloys containing about 7 wt.% Al are potential lightweight steels.

  4. Fabrication and Characterization of AL-AL4C3 Nanocomposite by Mechanical Alloying

    Science.gov (United States)

    Mohammad Sharifi, E.; Enayati, M. H.; Karimzadeh, F.

    Aluminum carbide (Al4C3) seems to be an ideal reinforcement for producing aluminum matrix composites. Al4C3 has high hardness and shear strength as well as a high melting point. The dispersion of Al4C3 particles in the matrix produces a pinning effect that reduces aluminum grain growth, which improves the mechanical properties. In this study, aluminum powders were mixed with 4.5 wt.% graphite and mechanically alloyed using a high-energy ball mill in order to produce Al-Al4C3 nanocomposite. The structural evaluation of powder particles after different milling times was studied by X-ray diffractometry, scanning electron microscopy and microhardness measurements. The aluminum crystallite size estimated with broadening of XRD peaks by Williamson-Hall formula. XRD results suggested that the grain size of aluminum decreased to nanometer range (30 nm) during ball milling. No Al4C3 formed during the mechanical alloying process. Milled powders were then annealed at 300-600 °C for 1 h under argon atmosphere. Annealing at temperatures higher than 300 °C led to formation of Al4C3 phase which increased as annealing temperature increased. Aluminum grain size remained in nanometer range after annealing process. The microhardness of powder particles increased after annealing. Both effects are due to the formation of nanosized Al4C3 particles.

  5. InAlGaAs/AlGaAs quantum wells: line widths, transition energies and segregation

    DEFF Research Database (Denmark)

    Jensen, Jacob Riis; Hvam, Jørn Märcher; Langbein, Wolfgang

    2000-01-01

    We investigate the optical properties of InAlCaAs/AlGaAs quantum wells pseudomorphically grown on GaAs using molecular beam epitaxy (MBE). The transition energies, measured with photoluminescence (PL), are modelled solving the Schrodinger equation, and taking into account segregation in the group...

  6. Directional Solidification and Mechanical Properties of NiAl-NiAlTa Alloys

    Science.gov (United States)

    Johnson, D. R.; Chen, X. F.; Oliver, B. F.; Noebe, R. D.; Whittenberger, J. D.

    1995-01-01

    Directional solidification of eutectic alloys is a promising technique for producing in-situ composite materials exhibiting a balance of properties. Consequently, the microstructure, creep strength and fracture toughness of directionally solidified NiAl-NiAlTa alloys were investigated. Directional solidification was performed by containerless processing techniques to minimize alloy contamination. The eutectic composition was found to be NiAl-15.5 at% Ta and well-aligned microstructures were produced at this composition. A near-eutectic alloy of NiAl-14.5Ta was also investigated. Directional solidification of the near-eutectic composition resulted in microstructures consisting of NiAl dendrites surrounded by aligned eutectic regions. The off-eutectic alloy exhibited promising compressive creep strengths compared to other NiAl-based intermetallics, while preliminary testing indicated that the eutectic alloy was competitive with Ni-base single crystal superalloys. The room temperature toughness of these two-phase alloys was similar to that of polycrystalline NiAl even with the presence of the brittle Laves phase NiAlTa.

  7. Thermodynamic Assessments of Al-In-Sb and Al-In-As Systems

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The experimental thermodynamic and phase diagram data of the Al-In-Sb and Al-In-As ternary systems were critically assessed.A set of self-consistent thermodynamic model parameters were obtained to describe the phase equilibria and the thermodynamic properties of two systems.In most cases,the calculated values agree very well with the experimental data.

  8. Ab initio phonon calculations for Ll(2) Ni3Al and B2NiAl

    NARCIS (Netherlands)

    Isaeva, E.I.; Lichtenstein, A.I.; Vekilov, Y.K.; Smirnova, E.A.; Abrikosov, I.A.; Simak, S.I.; Ahuja, R.; Johansson, B.

    2004-01-01

    The phonon spectra and phonon density of states of the Ni3Al and NiAl intermetallic compounds are calculated from first principles using the linear response method in conjunction with ultrasoft pseudopotentials. The calculated phonon dispersion curves are in good agreement with available experimenta

  9. Electronic circuits having NiAl and Ni.sub.3 Al substrates

    Energy Technology Data Exchange (ETDEWEB)

    Deevi, Seetharama C. (Midlothian, VA); Sikka, Vinod K. (Oak Ridge, TN)

    1999-01-01

    An electronic circuit component having improved mechanical properties and thermal conductivity comprises NiAl and/or Ni.sub.3 Al, upon which an alumina layer is formed prior to applying the conductive elements. Additional layers of copper-aluminum alloy or copper further improve mechanical strength and thermal conductivity.

  10. Electronic circuits having NiAl and Ni{sub 3}Al substrates

    Energy Technology Data Exchange (ETDEWEB)

    Deevi, S.C.; Sikka, V.K.

    1999-10-12

    An electronic circuit component having improved mechanical properties and thermal conductivity comprises NiAl and/or Ni{sub 3}Al, upon which an alumina layer is formed prior to applying the conductive elements. Additional layers of copper-aluminum alloy or copper further improve mechanical strength and thermal conductivity.

  11. Electronic states and spin-forbidden cooling transitions of AlH and AlF.

    Science.gov (United States)

    Wells, Nathan; Lane, Ian C

    2011-11-14

    The feasibility of laser cooling AlH and AlF is investigated using ab initio quantum chemistry. All the electronic states corresponding to the ground and lowest two excited states of the Al atom are calculated using multi-reference configuration interaction (MRCI) and the large AV6Z basis set for AlH. The smaller AVQZ basis set is used to calculate the valence electronic states of AlF. Theoretical Franck-Condon factors are determined for the A(1)Π→ X(1)Σ(+) transitions in both radicals and found to agree with the highly diagonal factors found experimentally, suggesting computational chemistry is an effective method for screening suitable laser cooling candidates. AlH does not appear to have a transition quite as diagonal as that in SrF (which has been laser cooled) but the A(1)Π→ X(1)Σ(+) transition transition of AlF is a strong candidate for cooling with just a single laser, though the cooling frequency is deep in the UV. Furthermore, the a(3)Π→ X(1)Σ(+) transitions are also strongly diagonal and in AlF is a practical method for obtaining very low final temperatures around 3 μK.

  12. Al-rich part phase relation in Al-Mg-Sc system at 430 ℃

    Institute of Scientific and Technical Information of China (English)

    夏长清; 曾凡浩; 古一

    2003-01-01

    Phase relation of the aluminium-magnesium-scandium system in the Al-rich range at 430 ℃ was investigated by means of multiphase diffusion couples along with electron probe microanalysis, X-ray diffraction and electron microscopy techniques. It consists of five single-phase fields, four 2-phase fields and one 3-phase field. The maximum solid solubilities of Mg and Sc in α(Al) solid solution at 430 ℃ are about 15.27%Mg(mole fraction) and 0.33%Sc, respectively. The maximum solid solubilities of Sc in Mg2Al3 and Mg17Al12 are about 1.08% and 0.03% at the same temperature. The diffusion path at 430 ℃ was constructed and interpreted by means of the Al-Mg-Sc equilibrium phase diagram assuming that local equilibrium is established at the phase boundaries.

  13. Serious Flaws in Korf et al.'s Analysis on Time Complexity of A*

    CERN Document Server

    Dinh, Hang

    2008-01-01

    Understanding the effect of a heuristic on the time complexity of the well-known A* search algorithm has been a subject of a large research body in AI. Among those researches is Korf et al.'s analysis (Korf & Reid, 1998; Korf et al., 2001; Korf, 2000a; Korf, 2000b), which concluded that the effect of a heuristic is to reduce the effective depth rather than effective branching factor. Since this conclusion conflicts with both previous analysis and recent analysis by other authors, we try to investigate the causes of such contradictions and finally find out that Korf et al.'s analysis has many serious flaws from which their main conclusion was drawn.

  14. FABRICATION OF Al/Al2O3 FGM ROTATING DISC

    Directory of Open Access Journals (Sweden)

    A. B. Sanuddin

    2012-06-01

    Full Text Available This study presents a method of fabricating a disc made of Al/Al2O3 functionally graded materials (FGM, using a powder metallurgy manufacturing process. The aim is to develop a processing method for a rotating disc made of FGM, by stacking the slurry, layer by layer in a radial direction. A three-layer functionally graded material of Al/Al2O3 is fabricated with compositions of 10, 20, 30 vol.% Al2O3. The ceramic composition increases from the discs inner (centre to the outer. The combination of these materials can offer the ability to withstand high temperature conditions whilst maintaining strength in extreme environments.

  15. In situ microscopy of rapidly heated nano-Al and nano-Al/WO3 thermites

    Science.gov (United States)

    Sullivan, Kyle T.; Chiou, Wen-An; Fiore, Richard; Zachariah, Michael R.

    2010-09-01

    The initiation and reaction mechanism of nano-Al and nano-Al thermites in rapid heating environments is investigated in this work. A semiconductor-based grid/stage was used, capable of in situ heating of a sample from room temperature to 1473 K, and at a rate of 106 K/s, inside an electron microscope. Nano-Al was rapidly heated in a transmission electron microscope, and before and after images indicate that the aluminum migrates through the shell, consistent with a diffusion-based mechanism. A nano-Al/WO3 composite was then heated in a scanning electron microscope. The results indicate that a reactive sintering mechanism is occurring for the nano-Al/WO3 thermite, as the products are found to be in surface contact and significantly deformed after the heating pulse.

  16. Surface phonon polariton characteristics of In(0.04)Al(0.06)Ga(0.90)N/AlN/Al(2)O(3) heterostructure.

    Science.gov (United States)

    Ng, S S; Lee, S C; Bakhori, S K Mohd; Hassan, Z; Abu Hassan, H; Yakovlev, V A; Novikova, N N; Vinogradov, E A

    2010-05-10

    Surface phonon polariton (SPP) characteristics of In(0.04)Al(0.06)Ga(0.90)N/AlN/Al(2)O(3) heterostructure are investigated by means of p-polarized infrared (IR) attenuated total reflection spectroscopy. Two absorption dips corresponding to In(0.04)Al(0.06)Ga(0.90)N SPP modes are observed. In addition, two prominent dips and one relatively weak and broad dip corresponding to the Al(2)O(3) SPP mode, In(0.04)Al(0.06)Ga(0.90)N/Al(2)O(3) interface mode, and Al(2)O(3) bulk polariton mode, respectively, are clearly seen. No surface mode feature originating from the AlN layer is observed because it is too thin. Overall, the observations are in good agreement with the theoretical predictions. PMID:20588890

  17. Microstructural defects modeling in the Al-Mo system

    International Nuclear Information System (INIS)

    In this work we have utilized computer simulation techniques to study microstructural defects, such as point defects and interfaces, in the Al-Mo alloy. Such alloy is taken as a model to study the Al(fcc)/U-Mo(bcc) interface. The EAM interatomic potential used has been fitted to the formation energy and lattice constant of the AlMo3 intermetallic. Formation of vacancies for both components Al and Mo and anti-sites, AlMo and MoAl, as well as vacancy migration was studied in this structure. We found that the lowest energy defect complex that preserves stoichiometry is the antisite pair AlMo+MoAl, in correspondence with other intermetallics of the same structure. Our results also suggest that the structure of the Al(fcc)/Mo(bcc) interface is unstable, while that of the Al(fcc)/Al5Mo interface is stable, as observed experimentally. (author)

  18. Production of Al nanocomposite reinforced by Fe-Al intermetallic, Al{sub 4}C{sub 3} and nano-Al{sub 2}O{sub 3} particles using wet milling in toluene

    Energy Technology Data Exchange (ETDEWEB)

    Razavi-Tousi, S.S., E-mail: ser105@mail.usask.ca [Islamic Azad University, Shahrood Branch, Shahrood (Iran, Islamic Republic of); Yazdani-Rad, R. [Materials and Energy Research Center, P.O. Box 31787/316, Karaj (Iran, Islamic Republic of); Manafi, S.A. [Islamic Azad University, Shahrood Branch, Shahrood (Iran, Islamic Republic of)

    2011-06-02

    Highlights: > Production of Al nanocomposite reinforced by Fe-Al intermetallic, Al{sub 4}C{sub 3} and nano-Al{sub 2}O{sub 3} particles using wet milling in toluene. > Production of Al{sub 4}C{sub 3} particles from mechanochemical reaction of Al with PCA. > Effect of second phase particles on sintering. - Abstract: Al matrix nanocomposites were produced by wet milling of Al and nano-alumina powders in a toluene media. X-ray diffraction patterns, inductively coupled plasma, carbon measurement analysis and scanning electron microscopy show that impurities introduced by decomposition of toluene and abrasion of balls and vials are uniformly dispersed in the Al matrix as Al{sub 4}C{sub 3} and Fe-Al intermetallic particles. Though producing homogenous nanocomposites, these second phase particles seem to have a retarding effect on densification of nanocomposite powders.

  19. The constitution of alloys in the Al-rich corner of the Al-Si-Sm ternary system

    International Nuclear Information System (INIS)

    The constitution of alloys and the liquidus surface in the Al-rich corner of the Al-Si-Sm ternary system were determined by the examination of controlled heated and cooled specimens, as well as heat-treated specimens by means of optical and scanning electron microscopy, energy-dispersive X-ray spectroscopy, differential thermal analysis and X-ray diffraction. The Al-rich corner of the Al-Si-Sm ternary system comprises five regions of primary crystallisation (αAl, βSi, Al3Sm, Al2Si2Sm and AlSiSm) with following characteristic invariant reaction sequences: ternary eutectic reaction L → αAl + βSi + Al2Si2Sm, and two liquidus transition reactions, i. e., L + Al3Sm → αAl + AlSiSm, and L + AlSiSm → αAl + Al2Si2Sm. Along with the position of ternary eutectic and both interstitial points in the Al-rich corner of the Al-Si-Sm ternary system, the temperatures for each reaction were determined. (orig.)

  20. Microscopic phase field study of the antisite defect of Ni3 Al in binary Ni-Al alloys

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The temporal evolution feature of a microscopic phase field model is utilized to study the antisite defects of L1 2-Ni 3 Al;this is quite different from other physicist’ interests.There are mainly two points in brief.Firstly,antisite defects Ni Al and Al Ni ,which are caused by the deviation from the stoichiometric Ni 3 Al,coexist in the Ni 3 Al phase.The surplus Ni atom in the Ni-rich side is prone to substitute Al thus producing the antisite defect Ni Al that maintains the stability of the L1 2 structure.In other case,the surplus Al atom in the Al-rich side is accommodated by a Ni sublattice consequently giving rise to antisite defect Al Ni .The calculated equilibrium occupancy probability of Ni Al is much higher than that of Al Ni .This point is generally in line with other theoretical and experimental works.Additionally,both Ni Al and Al Ni have a strong negative correlation to time step during the disorder-order transformation.Since the initial value of Ni Al and Al Ni on each site of the matrix is right at the concentration that we set,we can observe the decrease process of Ni Al and Al Ni from the initial disordered high anti-structure state to their respective equilibrium state,i.e.to the result of the ordering process further coarsening.

  1. TiAl-Nb melt interaction with AlN refractory crucibles

    Energy Technology Data Exchange (ETDEWEB)

    Kartavykh, A.V., E-mail: karta@girmet.ru [Institute of Chemical Problems for Microelectronics (IChPM), B. Tolmachevsky per. 5, 119017 Moscow (Russian Federation); Tcherdyntsev, V.V. [Moscow State Institute of Steel and Alloys (Technological University), Leninsky pr. 4, 119049 Moscow (Russian Federation); Zollinger, J. [ACCESS e.V., Intzestrasse 5, 52072 Aachen (Germany)

    2009-07-15

    The paper considers contamination of cast TiAl-based alloy, related microstructure evolution and chemical contact interaction when using refractory aluminium nitride crucibles/moulds as an alternative to the traditional Al{sub 2}O{sub 3}-, ZrO{sub 2}- and Y{sub 2}O{sub 3}-based oxide ceramics. A series of melting tests has been performed in resistive SiC electro-furnace with Ti-46Al-8Nb (at%) alloy in 99.99% purity AlN boat crucibles with fixed melt superheating times 5, 12 and 25 min at 1670 deg. C and consequent quenching with high-purity Ar gas flow. As-cast samples were examined by X-ray diffractometry, SEM, SIMS, EDX, EBSD and vacuum fusion analysis of O, N, C and S interstitials content with respect to the initial material. The key features of TiAl-Nb melt interaction with AlN ceramics are revealed. As a result of slow thermal dissociation AlN {yields} Al + N, and the reaction of nascent nitrogen with the melt, a solid continuous TiN-based reaction layer is formed up to 6.4 {mu}m in thickness, together with an enriched Al liquid film between it and the crucible wall. It causes perfect wetting of crucible with the melt and easy removal of the solidified sample. The partial suitability of AlN crucible is restricted by 12 min of the melt superheating from the point of view of invariable ({alpha}{sub 2} + {gamma})-microstructure and reasonable contamination of the as-cast samples.

  2. AlON的合成工艺%Synthesis technology of AlON

    Institute of Scientific and Technical Information of China (English)

    王习东; 李文超

    2001-01-01

    分析了合成AlON的各种方法。 用模式识别结 合神经网络对碳热还原氮化合成AlON工艺 进行了优化, 利用模式逆映射得到了理想的合成工艺参数。 对AlON体系进行了热力学初步 分析, 计算了温度为2  073  K时合成AlON的热力学参数状态图。 根据热力学参数状态图所确定的条件, 热压合成了AlON陶瓷。 对所合成的AlON试样进行了 X 射线衍射标定及部分物理性能的测定。 其密度为3.63  g/cm3, 约为其理论 密度的97.8%。%The synthesis technolog y of AlON ceramics was investigated. The program o f pattern recognition was used to optimize the parameters of AlON synthesi s process, and the proper parameters were obtained by inverse projection. The th ermodynamic properties of AlON were preliminary analyzed and estimate d, phase stability diagrams at 2  073  K were calculated. A lON ceramics was synthesized by hot-press sintering under the conditions given by phase stability diagram. The density of AlON is 3.63  g/cm3, about 97.8% of its th eoretic d ensity.

  3. Microstructure of Ni-Al powder and Ni-Al composite coatings prepared by twin-wire arc spraying

    Science.gov (United States)

    Wang, Ji-xiao; Wang, Gui-xian; Liu, Jing-shun; Zhang, Lun-yong; Wang, Wei; Li, Ze; Wang, Qi-xiang; Sun, Jian-fei

    2016-07-01

    Ni-Al powder and Ni-Al composite coatings were fabricated by twin-wire arc spraying (TWAS). The microstructures of Ni-5wt%Al powder and Ni-20wt%Al powder were characterized by scanning electronic microscopy (SEM) and energy dispersive spectroscopy (EDS). The results showed that the obtained particle size ranged from 5 to 50 μm. The morphology of the Ni-Al powder showed that molten particles were composed of Ni solid solution, NiAl, Ni3Al, Al2O3, and NiO. The Ni-Al phase and a small amount of Al2O3 particles changed the composition of the coating. The microstructures of the twin-wire-arc-sprayed Ni-Al composite coatings were characterized by SEM, EDS, X-ray diffraction (XRD), and transmission electron microscopy (TEM). The results showed that the main phase of the Ni-5wt%Al coating consisted of Ni solid solution and NiAl in addition to a small amount of Al2O3. The main phase of the Ni-20wt%Al coating mainly consisted of Ni solid solution, NiAl, and Ni3Al in addition to a small amount of Al and Al2O3, and NiAl and Ni3Al intermetallic compounds effectively further improved the final wear property of the coatings. TEM analysis indicated that fine spherical NiAl3 precipitates and a Ni-Al-O amorphous phase formed in the matrix of the Ni solid solution in the original state.

  4. Synthesis of Ti-Al porous perform

    Directory of Open Access Journals (Sweden)

    K. Naplocha

    2008-02-01

    Full Text Available Purpose: Article describes production method of intermetallic porous perform for reinforcing of composite materials. Usefulness of the high temperature self-propagating synthesis (SHS, with appropriate modification, to produce perform for production of composite was evaluated.Design/methodology/approach: Mixture of aluminum and titanium powder was cold isostatically pressed (CIPed and produced cylindrical pill was ignited in microwave field. Obtained structure usually have open porosity what enables for pressure infiltration with molten metal. The investigations of the structure of preforms on the scanning electron microscope (SEM were made.Findings: The produced performs in most cases reveal open porosity, uniform morphology and are suitable for infiltration process. After reaction Al-Ti compounds form partly globular structure with microhardness much higher than substratesResearch limitations/implications: In the actual stages of this work proposed method can be used for manufacturing of porous performs, which mainly contain Al3Ti. During reaction, mixture compacts with the molar ratio of Al/Ti=1 were transformed into inhomogeneous structure.Practical implications: Obtained perform can be widely used as the reinforcement to produce hybrid composite materials by the infiltration method. Aluminum casting alloys can be locally reinforced to improve hardness and resistance to oxidization at high temperature.Originality/value: Article is valuable for persons engaged in production of casting composite materials reinforced with porous perform. Proposed method allows to incorporate hard structures from Al-Ti compounds into aluminum casting.

  5. CALCULUL CINETOSTATIC AL MECANISMELOR PLANETARE CILINDRICE

    Directory of Open Access Journals (Sweden)

    Păun ANTONESCU

    2012-05-01

    Full Text Available În lucrare se prezintă o metodă analitică pentru calculul cinetostatic al mecanismului planetarmonomobil cu două roţi dinţate centrale. Se consideră mai întâi cazul general al schemelor cinematice cu douăroţi dinţate solidare tip satelit, în două variante practice (multiplicator şi reductor de turaţie. Este menţionatcazul particular al mecanismelor planetare cu o singură roată satelit cu angrenare dublă (exterioară şiinterioară. Pe baza modelului de analiză cinetostatică a mecanismului planetar monomobil cu două roţi dinţatecentrale, în finalul lucrării se abordează o problemă practică de calcul cinetostatic al unui mecanism planetarcilindric simplu folosit la capul de frezat pentru prelucrarea roţilor dinţate cilindrice cu dinţi curbi înhipocicloidă.

  6. Colombia frente al manejo del Presupuesto Nacional

    Directory of Open Access Journals (Sweden)

    Germán Enrique Reyes Forero

    2009-07-01

    Colombia pasa de 38 puntos en el 2007 a 46 puntos en el 2009, mejoría que no se corresponde con los múltiples escándalos de corrupción; ésta mejoría responde al manejo de tecnicismos como se intentará aclarar en el presente articulo.

  7. 75 FR 1420 - Alabama Disaster # AL-00025

    Science.gov (United States)

    2010-01-11

    ... From the Federal Register Online via the Government Publishing Office SMALL BUSINESS ADMINISTRATION Alabama Disaster AL-00025 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a notice of an Administrative declaration of a disaster for the State of Alabama dated...

  8. 76 FR 29810 - Alabama Disaster #AL-00037

    Science.gov (United States)

    2011-05-23

    ... From the Federal Register Online via the Government Publishing Office SMALL BUSINESS ADMINISTRATION Alabama Disaster AL-00037 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for Public Assistance Only for...

  9. 75 FR 26813 - Alabama Disaster #AL-00029

    Science.gov (United States)

    2010-05-12

    ... From the Federal Register Online via the Government Publishing Office SMALL BUSINESS ADMINISTRATION Alabama Disaster AL-00029 AGENCY: Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for the State of Alabama...

  10. 78 FR 4967 - Alabama Disaster #AL-00046

    Science.gov (United States)

    2013-01-23

    ... From the Federal Register Online via the Government Publishing Office SMALL BUSINESS ADMINISTRATION Alabama Disaster AL-00046 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a notice of an Administrative declaration of a disaster for the State of ALABAMA dated...

  11. 76 FR 62481 - Incapital LLC, et al.

    Science.gov (United States)

    2011-10-07

    ... From the Federal Register Online via the Government Publishing Office SECURITIES AND EXCHANGE COMMISSION Incapital LLC, et al.; Notice of Application September 30, 2011. AGENCY: Securities and Exchange Commission (``Commission''). ACTION: Notice of application for an order under section 12(d)(1)(J) of...

  12. 78 FR 22361 - Alabama Disaster #AL-00049

    Science.gov (United States)

    2013-04-15

    ... From the Federal Register Online via the Government Publishing Office SMALL BUSINESS ADMINISTRATION Alabama Disaster AL-00049 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a notice of an Administrative declaration of a disaster for the State of Alabama dated...

  13. 78 FR 26100 - Alabama Disaster #AL-00050

    Science.gov (United States)

    2013-05-03

    ... From the Federal Register Online via the Government Publishing Office SMALL BUSINESS ADMINISTRATION Alabama Disaster AL-00050 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a notice of an Administrative declaration of a disaster for the State of Alabama dated...

  14. 75 FR 3895 - Yale University, et al.;

    Science.gov (United States)

    2010-01-25

    ... notice at 74 FR 67851, December 21, 2009. Docket Number: 09-065. Applicant: U.S. Department of Homeland..., Quanta 200 FEG. Manufacturer: FEI Company, Czech Republic. Intended Use: See notice at 74 FR 67851... International Trade Administration Yale University, et al.; Notice of Consolidated Decision on Applications...

  15. 77 FR 7227 - Alabama Disaster #AL-00040

    Science.gov (United States)

    2012-02-10

    ... From the Federal Register Online via the Government Publishing Office SMALL BUSINESS ADMINISTRATION Alabama Disaster AL-00040 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for the State of Alabama...

  16. 75 FR 474 - Alabama Disaster #AL-00026

    Science.gov (United States)

    2010-01-05

    ... From the Federal Register Online via the Government Publishing Office SMALL BUSINESS ADMINISTRATION Alabama Disaster AL-00026 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for Public Assistance Only for...

  17. 76 FR 27141 - Alabama Disaster # AL-00036

    Science.gov (United States)

    2011-05-10

    ... From the Federal Register Online via the Government Publishing Office SMALL BUSINESS ADMINISTRATION Alabama Disaster AL-00036 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for the State of Alabama...

  18. 77 FR 60003 - Alabama Disaster #AL-00044

    Science.gov (United States)

    2012-10-01

    ... From the Federal Register Online via the Government Publishing Office SMALL BUSINESS ADMINISTRATION Alabama Disaster AL-00044 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for Public Assistance Only for...

  19. 75 FR 26814 - Alabama Disaster #AL-00031

    Science.gov (United States)

    2010-05-12

    ... From the Federal Register Online via the Government Publishing Office SMALL BUSINESS ADMINISTRATION Alabama Disaster AL-00031 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for Public Assistance Only for...

  20. The Science of al-Biruni

    CERN Document Server

    Sparavigna, Amelia Carolina

    2013-01-01

    Al-Biruni (973-1048) was one of the greatest scientists of all times. He was an astronomer, mathematician and philosopher, and studied physics and natural sciences. In this paper, we will discuss some of his experimental methods and some instruments he used.

  1. Creative Commons : Erfgoedinstelling als digitaal curator.

    NARCIS (Netherlands)

    Hoorn, Esther

    2008-01-01

    Zijn Creative Commons-licenties een ver-van-mijn-bed-show voor erfgoedinstellingen? Integendeel, betoogt Esther Hoorn. De instellingen kunnen ze gebruiken als ze rechthebbende zijn. Maar belangrijker nog: door het gebruik van deze licenties te stimuleren kunnen ze een spin in het web van netwerken r

  2. Management of respiratory symptoms in ALS.

    LENUS (Irish Health Repository)

    Hardiman, Orla

    2012-02-01

    Respiratory insufficiency is a frequent feature of ALS and is present in almost all cases at some stage of the illness. It is the commonest cause of death in ALS. FVC is used as important endpoint in many clinical trials, and in decision-making events for patients with ALS, although there are limitations to its predictive utility. There are multiple causes of respiratory muscle failure, all of which act to produce a progressive decline in pulmonary function. Diaphragmatic fatigue and weakness, coupled with respiratory muscle weakness, lead to reduced lung compliance and atelectasis. Increased secretions increase the risk of aspiration pneumonia, which further compromises respiratory function. Bulbar dysfunction can lead to nutritional deficiency, which in turn increases the fatigue of respiratory muscles. Early recognition of respiratory decline and symptomatic intervention, including non-invasive ventilation can significantly enhance both quality of life and life expectancy in ALS. Patients with respiratory failure should be advised to consider an advance directive to avoid emergency mechanical ventilation.

  3. Management of respiratory symptoms in ALS.

    LENUS (Irish Health Repository)

    Hardiman, Orla

    2011-03-01

    Respiratory insufficiency is a frequent feature of ALS and is present in almost all cases at some stage of the illness. It is the commonest cause of death in ALS. FVC is used as important endpoint in many clinical trials, and in decision-making events for patients with ALS, although there are limitations to its predictive utility. There are multiple causes of respiratory muscle failure, all of which act to produce a progressive decline in pulmonary function. Diaphragmatic fatigue and weakness, coupled with respiratory muscle weakness, lead to reduced lung compliance and atelectasis. Increased secretions increase the risk of aspiration pneumonia, which further compromises respiratory function. Bulbar dysfunction can lead to nutritional deficiency, which in turn increases the fatigue of respiratory muscles. Early recognition of respiratory decline and symptomatic intervention, including non-invasive ventilation can significantly enhance both quality of life and life expectancy in ALS. Patients with respiratory failure should be advised to consider an advance directive to avoid emergency mechanical ventilation.

  4. Al/Cl2 molten salt battery

    Science.gov (United States)

    Giner, J.

    1972-01-01

    Molten salt battery has been developed with theoretical energy density of 5.2 j/kg (650 W-h/lb). Battery, which operates at 150 C, can be used in primary mode or as rechargeable battery. Battery has aluminum anode and chlorine cathode. Electrolyte is mixture of AlCl3, NaCl, and some alkali metal halide such as KCl.

  5. Cryptanalysis on Cheng et al. protocol

    Science.gov (United States)

    Thakur, Tejeshwari

    2016-06-01

    Deployment of new node in any wireless sensor network is a sensitive task. This is the reason why, an Access Control Protocol is required in WSN. In this paper, we demonstrate that Access Control Protocol proposed by Cheng et al.[1] for Wireless Sensor Network is insecure. The reason is that this protocol fails to resist the active attack.

  6. Del desarrollo rural al desarrollo territorial

    OpenAIRE

    Moyano Estrada, Eduardo

    2010-01-01

    5 páginas.-- Trabajo presentado al Seminario Ruraland celebrado en Antequera (Málaga) el 26 de mayo de 2010.-- Presentado como ponencia a la Jornada de debate "El desarrollo rural en la U.E. despues de 2013" celebrado en Aracena (Huelva) el 10 de junio de 2010 (adjuntado Pdf).

  7. Wallada Bint al Mustakfi entre dos culturas

    Directory of Open Access Journals (Sweden)

    shreen Mahmoud Al Refai

    2013-10-01

    Full Text Available La princesa cordobesa Wallada Bint al Mustakfi bil-lah, hija del califa al Mustakfi Muhammad Ibn Abdel Rahman Ibn Obaidil-lah Ibn Al Nasir lidin Al-lah era una poetisa estimable, a quien los grandes poetas no podían superar. Era una mujer única, guapa y decente. Mantenía una relación sentimental con el  poeta y visir Ibn Zaydún. Dicha pasión, narrada por los poemas escritos por ambos amantes, se terminó por la separación debida a los celos, también de ambos;  al poeta le gustó la voz de una esclava de la princesa. Eso dio rabia a la última. Movido también por los celos, Ibn Zaydún dedicó una epístola satírica al visir Ibn Abdús, que estaba enamorado de Wallada. Tal hecho también irritó a la princesa. A pesar de tener amantes y admiradores, Wallada murió sin casarse al  día 2 de safar de 480 (o 484 de la Híjira pasando los ochenta años Me han llamado la atención el carácter tan culto, independiente y liberal de aquella mujer, su relación amorosa con Ibn Zaydún que no acabó felizmente y los muchos años que vivió sin casasre. Parece que la vida de la princesa hispano-musulmana llamó también la atención de muchos escritores árabes y españoles. Prueba de ello son varias obras literarias escritas en árabe y en español sobre Wallada e Ibn Zaydún. Por consiguiente, me resulta muy interesante realizar un estudio comparativo sobre este tema averiguando si, o no, la diferencia de culturas influiría en las opiniones  de los autores sobre la vida sentimental de aquella poetisa cordobesa.

  8. ELECTROLYSIS OF SWINE MANURE EFFLUENTS USING THREE DIFFERENT ELECTRODES Fe-Fe, Al-Al AND Fe-Al

    Directory of Open Access Journals (Sweden)

    S. Rahman

    2014-01-01

    Full Text Available Swine effluent with high organic strength need to be treated to make it suitable for applying to crop/pasture fields, or discharging to any waterways. Electrocoagulation is a relatively simpler and cheaper technique over biological and chemical treatment methods currently used to treat high-strength industrial and municipal wastewater. The performance of an electrocoagulation system mainly depends on the pH, Electrical Conductivity (EC of the medium, Chemical Oxygen Demand (COD loading rates and catalytic activity of the electrodes used. In this research, a study was conducted to compare the pollutant removal efficiencies of three electrodes (Fe-Fe, Al-Al and Fe-Al with three electric current levels (500, 1000 and 2000 mA while treating swine manure effluents. The electrochemical cell consisted of two parallel rectangular plates (90×25×1.5 mm of Iron (Fe-Fe, Aluminum (Al-Al and Iron-Aluminum (Fe-Al, later on described as hybrid electrodes; immersed in a beaker with 550 mL swine effluents and powered by a Direct Current (DC supply. All studies were conducted in batches at room temperature. In general, removal efficiencies were increased with increasing current densities and electrolysis times for electrodes evaluated. Aluminum electrodes outperformed iron and hybrid (iron-aluminum electrodes in removing Total Phosphorus (TP at all current density levels tested. Overall, use of hybrid electrodes resulted in better COD removal. For the same treatment times (1200 s at higher current density (21 mA cm-2, hybrid electrodes removed about 100% COD, which are about 1.9 and 1.3 times higher than those of aluminum and iron electrodes, respectively. Iron electrodes showed the highest removal efficiency (85% for Total Organic Carbon (TOC at 21 mA cm-2 current density and 1200 s treatment time. Overall, lower Specific Electrical Energy Consumptions (SEECs per kg of Pollutants (TP, COD and TOC were estimated for the aluminum

  9. Investigation Of Water Assisted Phase Transformation Process From AlPO4-5 to AlPO4-tridymite

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Suochang; Zhao, Zhenchao; Hu, Mary Y.; Han, Xiuwen; Hu, Jian Z.; Bao, Xinhe

    2016-03-15

    Water assisted phase transformation process from crystalized AlPO4-5 to AlPO4-tridymite was studied by the combination of X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and in situ multinuclear MAS NMR. It is found that water first activates the residue amorphous aluminophosphate in crystalized AlPO4-5 sample through hydrolysis and condensation reactions. Then the activated aluminophosphate species reassemble into AlPO4-tridymite crystalline. Meanwhile, AlPO4-5 transforms into orthorhombic phase during heating process. With further crystallization of AlPO4-tridymite, the amorphous phase is gradually consumed, and mass transportation between AlPO4-5 and AlPO4-tridymite is established through gradually amorphization of AlPO4-5. Finally, most of the AlPO4-5 transforms into the thermodynamically stable dense phase AlPO4-tridymite.

  10. Medien als Lernform und die Trimediale Redaktion

    Directory of Open Access Journals (Sweden)

    Wolf Hilzensauer

    2015-01-01

    Full Text Available Der vorliegende Artikel beschreibt ein Konzept für eine handlungsorientierte Medienpädagogik im Bildungsbereich. Im Mittelpunkt steht dabei die SO!-Campusredaktion, die als Methode für expansives Lernen die Möglichkeit bietet, unabhängig von Thema oder Medium die Verantwortung für den Lernprozess in die Hände der Lernenden zu legen. Der Dokumentation von Reflexion über den Lernprozess wird dabei eine besondere Bedeutung zugesprochen. Gleichzeitig werden unterschiedliche mediale Gestaltungsmöglichkeiten (Audio/Radio, Video/Fernsehen und Zeitung – sowohl als Print- als auch als Onlinemedium vorgestellt, die durch das Konzept BYOD – bring your own device – auch einfach und niederschwellig im Bildungskontext umsetzbar sind. Dadurch ergeben sich innovative Möglichkeiten, einen Lernprozess sichtbar zu machen und gleichzeitig eine Grundlage für eine alternative Leistungsbeurteilung anzubieten. Die SO!-Campusredaktion wird derzeit an der Pädagogischen Hochschule Salzburg in Kooperation mit dem Communitysender FS1 und der Radiofabrik entwickelt und erprobt. Community Medien nehmen als MedienpartnerInnen eine bedeutende Stellung ein: Durch ihren offenen Zugang zu Know How und Equipment sowie durch die Möglichkeit, Medienproduktionen über die verfügbaren Distibutionskanäle (Radiofrequenz oder Sendeplatz einer breiten Bevölkerung zugänglich zu machen, gewinnt die Medienpädagogik einen wichtigen Mehrwert in ihrer schulischen und außerschulischen Arbeit. (Dieser Artikel knüpft an den Artikel "BYOD, Smartphonefilme und webbasierte Videoschnittprogramme" der Medienimpulse, Ausgabe 2/2014, an.

  11. A high degree of enhancement of strength of sputter deposited Al/Al2O3 multilayers upon post annealing

    International Nuclear Information System (INIS)

    We report here an order of magnitude enhancement of strength of sputter deposited Al/Al2O3 multilayers after annealing. The increase in strength is shown to be mostly associated with the precipitation of extremely fine γ-Al2O3, 5–10 nm in diameter, in Al layers. This provides a new method of achieving high strength in Al/Al2O3 multilayers that cannot be explained by the Koehler effect or modified Hall–Petch, which will lead to the growth and development of new generation of Al/Al2O3 multilayers. We also examine the fracture behavior of the post annealed Al/Al2O3 multilayered composites with TEM and density functional theory (DFT) simulations. DFT showed that the multilayers are not likely to delaminate at the Al/Al2O3 interface, consistent with the experimental observations. The simulations are also used to determine elastic constants for the γ-Al2O3 phase and to calculate a driving force for O transport from the γ-Al2O3 to the Al layers. The formation of these precipitates is consistent with DFT calculations, which predict an energetic driving force for the dissolution of O atoms from the γ-Al2O3 layers into the Al layers

  12. Spectroscopic analysis of the open 3d subshell transition metal aluminides: AlV, AlCr, and AlCo

    Science.gov (United States)

    Behm, Jane M.; Brugh, Dale J.; Morse, Michael D.

    1994-10-01

    Three open 3d subshell transition metal aluminides, AlV, AlCr, and AlCo, have been investigated by resonant two-photon ionization spectroscopy to elucidate the chemical bonding in these diatomic molecules. The open nature of the 3d subshell results in a vast number of excited electronic states in these species, allowing bond strengths to be measured by the observation of abrupt predissociation thresholds in a congested optical spectrum, giving D00(AlV)=1.489±0.010 eV, D00(AlCr)=2.272±0.009 eV, and D00(AlCo)=1.844±0.002 eV. At lower excitation energies the presence of discrete transitions has permitted determinations of the ground state symmetries and bond lengths of AlV and AlCo through rotationally resolved studies, giving r0` (AlV, Ω`=0)=2.620±0.004 Å and r0` (AlCo, Ω`=3)=2.3833±0.0005 Å. Ionization energies were also measured for all three species, yielding IE(AlV)=6.01±0.10 eV, IE(AlCr)=5.96±0.04 eV, and IE(AlCo)=6.99±0.17 eV. A discussion of these results is presented in the context of previous work on AlCu, AlNi, AlCa, and AlZn.

  13. In-situ synthesized (Al3Zr+Al2O3)p/A356 composites by direct melt reaction in Al-Zr-O system

    Institute of Scientific and Technical Information of China (English)

    赵玉涛; 李忠华; 程晓农; 戴起勋; 蔡兰

    2003-01-01

    A novel in-situ reaction system Al-Zr-O was developed. In situ Al3Zr and Al2O3 particulate reinforced A356 alloy matrix composites have been fabricated by direct melt reaction method. The results show that the maximum sizes of Al3Zr and Al2O3 particulates synthesized in the system ZrOCl2-A356 are 1 μm and 3 μm respectively, and they are well distributed in the matrix. The investigation shows that the Al3Zr crystal is in the shape of polyhedron and rectangle. There is a faceted growth phenomenon on Al3Zr crystal surface. It is firstly found that the Al3Zr crystal grows in the mechanism of twinning. The twinning plane is (1 1 4), and the twinning direction is [2 2 1]. The crystal morphology of in-situ α-Al2O3 particulate is rectangle or sphere. Furthermore, (Al3Zr+Al2O3)p/A356 composites have not only higher tensile strength at room temperature (376.2 MPa) but also higher yield strength (319.4 MPa) and higher tensile strength at elevated temperature (200 ℃) than those of the A356 alloy. The dry sliding wear test shows that the wear resistance of the (Al3Zr+Al2O3)p/A356 composites is greatly enhanced with increasing particulate volume fraction.

  14. Electrical defects in AlGaN and InAlN

    Science.gov (United States)

    Johnstone, D.; Leach, Jacob H.; Kovalskii, Vladimir A.; Fan, Qian; Xie, Jingqiao; Morkoç, Hadis

    2009-02-01

    Compound semiconductors based on GaN have multiple functional applications. Useful compositions include GaN, and ternary and quaternary compositions of (AlGaIn)N. Defects arising from lattice mismatch, point defects, or impurities may act as electrical trapping centers and degrade device efficiency. Current-voltage, capacitance-voltage, thermal admittance spectroscopy (TAS), and deep level transient spectroscopy (DLTS) measurements are applied to characterize the defects in Al0.40Ga0.80N and In0.18Al0.82N in this report. Broad peaks with a shoulder at high temperature dominate the DLTS spectra in each of the materials. An acceptor trap associated with a dislocation appears at 340 K in AlGaN. The defect has an energy of 0.2 eV and capture cross section of 10-21 cm2. A second trap at 0.35 eV, 10-14 cm2 appears in the TAS measurements in addition to the trap at 0.2 eV. Defects in InAlN are dominated by a peak near 150 K. Two traps appear in the TAS measurements. Both traps in the InAlN are acceptors, based on a lack of field dependent emission rates using double pulse DLTS (DDLTS). The two energy levels in InAlN appear to be coupled, with only one state occupied at a time.

  15. Thermoelectric Powers of Cells With NaF-AlF3-Al2O3 Melts

    Science.gov (United States)

    Flem, Belinda E.; Xu, Qian; Kjelstrup, Signe; Sterten, Åsmund

    2001-07-01

    A thermodynamic description of the Peltier heat at the aluminum and the oxygen electrode in the system NaF-AlF3-Al2O3 is given. The thermoelectric power in melts with molar ratios n NaF/n AlF3 from 3.0 to 1.0, saturated with alumina are measured. Seebeck coefficients for molten fluoride electrolytes saturated with alumina, electrolytes that are relevant for aluminum electrowinning electrolysis cells, are reported. The results allow determinations of Peltier heats of aluminum, oxygen and carbon electrodes in NaF-AlF3 electrolytes saturated with alumina. For molar ratios of n NaF/n AlF3 between 2.6 and 1.2, there is a Peltier heating of the aluminum cathode. This heating is in the same order of magnitude as the electrolyte Joule heat, when the current density is 0.7 A cm-2. For molar ratio n NaF/n AlF3 equal to 1.0 the Peltier effect at the aluminum electrode approaches zero. From theoretical considerations we expect a drop also for molar ratio 3.0. For the anode we report a Peltier cooling that is larger than the heat produced by the anodic overvoltage, in melts with NaF/AlF3 molar ratio between 2.6 and 1.2 saturated with alumina.

  16. PRECIPITATION HARDENING IN B2-ORDERED NiAl BY Ni2AlTiCOMPOUND

    Institute of Scientific and Technical Information of China (English)

    W.H. Tian; K. Ohishi; M. Nemoto

    2001-01-01

    Microstructural variations and correlated hardness changes in B2-ordered NiAl containing fine precipitation of Ni2AlTi have been investigated by means of transmission electron microscopy (TEM) and hardness tests. The amount of age hardening is not large as compared to the large microstructural variations during aging. TEM observations have revealed that the L21-type Ni2AlTi precipitates keep a lattice coherency with the NiAl matrix at the beginning of aging. By longer periods of aging Ni2AlTi precipitates lose their coherency and change their morphology to the globular ones surrounded by misfit dislocations. The temperature dependence of the yield strength of precipitate-containing B2-ordered NiAl was investigated by compression tests over the temperature range of 873-1273K. The fine precipitation of Ni2AlTi was found to enhance greatly the yield strength and the high-temperature strength is comparison with that of superalloy Mar-M200.``

  17. Fabrication and Mechanical Properties of Al_2O_3/TiAl Composites

    Institute of Scientific and Technical Information of China (English)

    AI Taotao

    2009-01-01

    Al_2O_3/TiAl composites were successfully fabricated by hot-press-assisted exother-mic dispersion method with elemental powder mixtures of Ti,Al TiO_2 and Nb_2O_5,and the micro-structure and mechanical properties were investigated.The results indicate the fine Al_2O_3 particles tend to disperse on the grain boundaries.The grain size of TiAl matrix decreases and the hardness increases with increasing Nb_2O_5 content.The bending strength and fracture toughness reach to a maximum when Nb_2O_5 content is 6 wt%,under 642 Mpa and 6.69 Mpa·m ~(1/2) ,respectively.Based on the fractography and the observation of crack propagation path,it is concluded that the strengthening and toughening of such composites at room temperature can be attributed to the refinement of the TiAl matrix,the de-flection behavior in the crack propagation and the dispersion of Al_2O_3 particles.

  18. Neutronic comparison of the nuclear fuels U3Si2/Al and U-Mo/Al

    International Nuclear Information System (INIS)

    The search for materials that allow the fabrication of nuclear fuels with higher uranium densities comes from the mid 50s. Today, a high density and low enriched nuclear fuel based on γ-UMo alloys is the most promising fuel to replace the U3Si2/Al dispersion fuel used worldwide in research and material test reactors. Alloys of uranium-molybdenum are prepared with 6 to 10% Mo addition and can be manufactured as dispersion or monolithic fuels. The aim of this paper is to compare the infinite multiplication factor (K∞), obtained through neutronic calculation with the code Scale 6, for aluminum coated plates reflected in all directions containing U3Si2/Al and U-Mo/Al dispersion fuels. The U3Si2/Al dispersion fuel used in the calculation has an uranium density of 4 gU/cm3 and the U-Mo-Al dispersion fuels have densities ranging from 4 to 7.52 gU/cm3 and 7 and 10% Mo addition. The results show that the K∞ calculated for U-Mo/Al fuels is lower than that for U3Si2/Al fuel and increases between the uranium densities of 4 and 5 gU/cm3 and decreases for higher uranium densities. (author)

  19. Microstructure of Ni-Al powder and Ni-Al composite coatings prepared by twin-wire arc spraying

    Institute of Scientific and Technical Information of China (English)

    Ji-xiao Wang; Gui-xian Wang; Jing-shun Liu; Lun-yong Zhang; Wei Wang; Ze Li; Qi-xiang Wang; Jian-fei Sun

    2016-01-01

    Ni–Al powder and Ni–Al composite coatings were fabricated by twin-wire arc spraying (TWAS). The microstructures of Ni-5wt%Al powder and Ni-20wt%Al powder were characterized by scanning electronic microscopy (SEM) and energy dispersive spec-troscopy (EDS). The results showed that the obtained particle size ranged from 5 to 50μm. The morphology of the Ni–Al powder showed that molten particles were composed of Ni solid solution, NiAl, Ni3Al, Al2O3, and NiO. The Ni–Al phase and a small amount of Al2O3 parti-cles changed the composition of the coating. The microstructures of the twin-wire-arc-sprayed Ni–Al composite coatings were characterized by SEM, EDS, X-ray diffraction (XRD), and transmission electron microscopy (TEM). The results showed that the main phase of the Ni-5wt%Al coating consisted of Ni solid solution and NiAl in addition to a small amount of Al2O3. The main phase of the Ni-20wt%Al coating mainly consisted of Ni solid solution, NiAl, and Ni3Al in addition to a small amount of Al and Al2O3, and NiAl and Ni3Al intermet-allic compounds effectively further improved the final wear property of the coatings. TEM analysis indicated that fine spherical NiAl3 pre-cipitates and a Ni–Al–O amorphous phase formed in the matrix of the Ni solid solution in the original state.

  20. Mechanical Properties and Microstructure of Neutron Irradiated Cold-worked Al-1050 and Al-6063 Alloys

    International Nuclear Information System (INIS)

    The impact of neutron irradiation on the internal microstructure, mechanical properties and fracture morphology of cold-worked Al-1050 and Al-6063 alloys was studied, using scanning and transmission electron microscopy, and tensile measurements. Specimens consisting of 50 mm long and 6 mm wide gauge sections, were punched out from Al-1050 and Al-6063 23% cold-worked tubes. They were exposed to prolonged neutron irradiation of up to 4.5x1025 and 8x1025 thermal neutrons/m2 (E -3 s-1. In general, the uniform and total elongation, the yield stress, and the ultimate tensile strength increase as functions of fluence. However, for Al-1050 a decrease in the ultimate tensile strength and yield stress was observed up to a fluence of 1x1025 thermal neutrons/m2 which then increase with thermal neutrons fluence. Metallographic examination and fractography for Al-6063 revealed a decrease in the local area reduction of the final fracture necking. This reduction is accompanied by a morphology transition from ductile transgranular shear rupture to a combination of transgranular shear with intergranular dimpled rupture. The intergranular rupture area increases with fluence. In contrast, for Al-1050, fracture morphology remains ductile transgranular shear rupture and the final local area reduction remains almost constant No voids could be observed in either alloy up to the maximum fluence. The dislocation density of cold-worked Al was found to decrease with the thermal neutron fluence. Prolonged annealing of unirradiated cold-worked Al-6063 at 52 degree led to similar results. Thus, it appears that, under our irradiation conditions, whereby the temperature encompassing the samples increases the exposure to this thermal field is the major factor influencing the mechanical properties and microstructure of aluminum alloys

  1. An Epidemiological Study of Cutaneous Leishmaniasis in Al-Jabal Al-Gharbi, Libya

    Science.gov (United States)

    Abdellatif, Manal Z. M.; El-Mabrouk, Khamis

    2013-01-01

    Cutaneous leishmaniasis (CL) is an endemic parasitic infection in the Mediterranean region, including Libya and its Al-jabal Al-gharbi province. We aimed at studying the occupational relevance as well as other epidemiological aspects of CL. We investigated 140 CL cases who attended at Gharyan outpatient polyclinic during a period of 6 months in 2009. CL infection was clinically diagnosed and confirmed by demonstration of Leishmania parasites on smears from lesions. Our findings showed that males were more affected than females (P=0.04), and people above 10-years were more affected than younger ones (P=0.0001). A significant percent of CL cases belonged to Al-Kawasem subprovince (P=0.0001). Farm-related activities were the most frequent occupations among CL cases (P=0.04). In addition to farm workers, housewives and students are at risk groups since they are engaged at farm activities. Moreover, those who have occupations that require staying outdoors for a part of night, e.g., policemen, are also at risk. Compared to children, adult CL patients had multiple lesions (P=0.001) that were more prevalent in their upper and lower extremities than the face (P=0.0001). We conclude that CL is a major health problem in Al-jabal Al-gharbi province of Libya. The presence of rodents and sandflies makes it a suitable environment for Leishmania to spread in an endemic epidemiological pattern. Being engaged in farming activities or outdoor occupations increases the risk of infection. Various clinical patterns of CL suggest the presence of more than 1 species of Leishmania at Al-jabal Al-gharbi province. We propose that the 2 species responsible for CL in this area are L. major and L. tropica. Further investigations to identify the leishmanial species responsible for CL at Al-jabal Al-gharbi together with adoption of preventive and control programs are needed. PMID:23467624

  2. An epidemiological study of cutaneous leishmaniasis in Al-jabal Al-gharbi, Libya.

    Science.gov (United States)

    Abdellatif, Manal Z M; El-Mabrouk, Khamis; Ewis, Ashraf A

    2013-02-01

    Cutaneous leishmaniasis (CL) is an endemic parasitic infection in the Mediterranean region, including Libya and its Al-jabal Al-gharbi province. We aimed at studying the occupational relevance as well as other epidemiological aspects of CL. We investigated 140 CL cases who attended at Gharyan outpatient polyclinic during a period of 6 months in 2009. CL infection was clinically diagnosed and confirmed by demonstration of Leishmania parasites on smears from lesions. Our findings showed that males were more affected than females (P=0.04), and people above 10-years were more affected than younger ones (P=0.0001). A significant percent of CL cases belonged to Al-Kawasem subprovince (P=0.0001). Farm-related activities were the most frequent occupations among CL cases (P=0.04). In addition to farm workers, housewives and students are at risk groups since they are engaged at farm activities. Moreover, those who have occupations that require staying outdoors for a part of night, e.g., policemen, are also at risk. Compared to children, adult CL patients had multiple lesions (P=0.001) that were more prevalent in their upper and lower extremities than the face (P=0.0001). We conclude that CL is a major health problem in Al-jabal Al-gharbi province of Libya. The presence of rodents and sandflies makes it a suitable environment for Leishmania to spread in an endemic epidemiological pattern. Being engaged in farming activities or outdoor occupations increases the risk of infection. Various clinical patterns of CL suggest the presence of more than 1 species of Leishmania at Al-jabal Al-gharbi province. We propose that the 2 species responsible for CL in this area are L. major and L. tropica. Further investigations to identify the leishmanial species responsible for CL at Al-jabal Al-gharbi together with adoption of preventive and control programs are needed.

  3. Two medieval Maghreb chronicles: Al-Ḏajira Al-Saniyya y el Rawd al-Qirtas

    Directory of Open Access Journals (Sweden)

    Lidia Fernández Fonfría

    2010-03-01

    Full Text Available In the present communication I intend to expose my conclusions on asmall comparative study between two of the earliest Maghreb chronicles throwing information about the North African tribe of Banu Mar÷n arrival to the throne in the thirteenth century Maghreb. With these common features, allowing a more complete picture of anera, which is undoubtedly the least known of the merinid period, their beginning. The similarities and influences between them are such that there are different theories about a possiblecommon authorship. After concluding the study and subsequent analysis of these works, can be extracted that there are substantial differences on a structural and stylistic level that hinder the possible absolute identification of author of the Dhakh÷ra al-Saniyyawith the author of RawÅ al-QirÐās.

  4. AlSb precipitate evolution during Sb implantation in Al: experiment and theory

    International Nuclear Information System (INIS)

    Precipitate evolution during ion implantation has been studied in the model system Sb-implanted Al. Transmission electron microscopy was used to determine the size distribution of AlSb crystallites as a function of fluence, flux, and sample temperature. There was a dramatic increase in average size, accompanied by a decrease in number density, for increasing fluence, for decreasing flux, and for increasing temperature. A new theoretical model for the evolution of the precipitate size distribution has been developed which incorporates both thermal processes and implantation effects. Numerical solutions for the AlSb system using physically realistic parameters agree qualitatively with the experimentally observed evolutions

  5. AL-HIKMAH AL-MUTA‘ÂLIYYAH PEMIKIRAN METAFISIKA EKSISTENSIALISTIK MULLA SHADRA

    Directory of Open Access Journals (Sweden)

    Sholihan Sholihan

    2015-04-01

    Full Text Available Among the meritorious figures that develop the illuminative thought initiated by Suhrawardi is Shadr al-Dîn  al-Shirazi, also known as Mulla Sadra. He is well known with his thought of al-Hikmah al-Muta'âliyyah or transcendent theosophy, an effort of harmonizing revelation, gnosis, and philosophy. He inflame an idea where the logic buried in the sea of light gnosis. He called the synthesis—one that he considered to be the particular basis of three major paths to truth for man, namely: revelation (wahy or shar', intellection ('aql, and mystical vission (Kashf—as al-Hikmah al-Muta‘âliyyah or transcendent theosophy. He has managed to make synthesis between deductive method of the Peripatetic, method of illumination, method of the odyssey of ‘irfân or Sufism, and method of Kalam. When his thought is compared with existentialistic thought of West, then there is a point of similarities among them not only in terms of technical language, but also in substantive matters.Abstract: Di antara tokoh yang berjasa mengembangkan pemikiran iluminatif dari Suhrawardi adalah Shadr al-Dîn  al-Syirâzî atau Mulla Shadra yang populer dengan pemikirannya tentang al-Hikmah al-Muta’âliyyah atau teosofi transenden, suatu upaya harmonisasi wahyu, gnosis, dan filsafat. Dia menggelorakan sebuah pemikiran di mana logika dibenamkan ke dalam lautan cahaya gnosis. Ia menyebut sintesisnya—yang ia anggap menjadi dasar khususnya tentang tiga jalan besar menuju kebenaran bagi manusia, yakni: wahyu (wahy atau syar’, intellection (‘aql, dan keterbukaan secara mistik (kasyf—dengan al-Hikmah al-Muta’âliyyah atau teosofi transenden. Dia telah berhasil melakukan sintesis antara metode deduktif dari peripatetik, metode illuminasi, metode pengembaraan dari ‘irfân atau sufisme, dan metode kalâm. Ketika pemikirannya diperbandingkan dengan pemikiran eksistensialistik Barat, maka ada titik kesamaan tidak saja dari segi teknis kebahasaan, melainkan juga pada

  6. Hardness Measurement of (TiB2-TiAl)/TiAl Symmetrically Function Gradient Materials

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    (TiB2-TiAl)/TiAl symmetrically function gradient materials (FGM) were prepared by spark plasma sintering (SPS). Owing to the difference of the thermal expansion coefficients between TiB2 and TiAl, a compressive surface stress was introduced to the FGM by the thermal expansion mismatch. The hardness values of the uniform materials and the FGM were tested, respectively. For the FGM with a compressive surface stress, hardness is obviously superior to that of the uniform material.When the FGM was subjected to heat treatment,the hardness decreased due to a partial relaxation of the compressive surface stress.

  7. A 25-year replication of Katz et al.'s (1988) metaphor norms.

    Science.gov (United States)

    Campbell, Spencer J; Raney, Gary E

    2016-03-01

    Research in metaphor processing has made extensive use of the normed metaphor database created by Katz, Paivio, Marschark, & Clark (Metaphor and Symbolic Activity, 3, 191-214, 1988). Because of the plasticity of figurative language, we conducted a renorming of selected metaphors from the database on a new student population. Correlations between Katz et al.'s and the present data showed that the pattern of responses has remained highly consistent across time and populations. The consistency of the normative ratings allows us to be confident in future research that will use the Katz et al. collection. PMID:25772671

  8. Influence of matrix characteristics on fracture toughness of high volume fraction Al2O3 / Al-AlN composites

    OpenAIRE

    Nagendra, N.; Jayaram, V

    2000-01-01

    The role of matrix microstructure on the fracture of Al-alloy composites with 60 % volume of alumina particulates has been studied. The matrix composition and microstructure were systematically varied by changing the infiltration temperature and heat treatment. Characterisation was carried out by a combination of metallography, hardness measurements and fracture studies conducted on compact tension (CT) specimens to study the fracture toughness and crack growth in the composites. The composit...

  9. Electrochemical corrosion behavior of arc sprayed Zn-Al coatings

    Institute of Scientific and Technical Information of China (English)

    LIU Yan; ZHU Zi-xin; CHEN Yong-xiong; XU Bin-shi; MA Shi-ning; LI Zhuo-xin

    2004-01-01

    Cored wires and high velocity arc spraying (HVAS) technique were applied to produce high Al content Zn-Al alloy coatings on low carbon steel substrates. The electrochemical corrosion behaviors of Zn, Al and Zn-Al coatings were studied with potentiodynamic measurement in 5 % NaCl solution. Compared with pure Zn, pure Al and Zn-15Al coatings, Zn-26Al coatings show a higher corrosion resistance in salt solution. The potentiodynamic polarization tests show that the corrosion resistance of Zn-Al coatings increases as Al content is raised. Pure Al coating exhibits different electrochemical behaviors with other coatings. The corrosion initiated at the micro-pores of the coating and the underlying corrosion mechanism is very similar to that of the pitting corrosion.

  10. Questioning of Authentication and Epistemology in Tafsir al-Jilani

    Directory of Open Access Journals (Sweden)

    Irwan Masduqi

    2012-06-01

    Full Text Available In this research, the author critically analyzes a biography of Shaikh ‘Abd al-Qadir al-Jilani containing sacred myths. The analyst of sacred myth about ‘Abd al-Qadir al-Jilani is based on the approach of applied anthropology to distinguish between the myths that have  positive and negative values for Muslim society. This research then analyzes the authenticity of Tafsir al-Jilani and the epistemology of his inter- pretation. ‘Abd al-Qadir al-Jilani is the founder of Qadiriyah. Qadiriyah doctrines has been widely accepted by traditional Muslim groups in Muslim world, so that the study of Tafsir al-Jilani is very meaningful for the followers of Qadiriyah in particu- lar and the lovers of Quranic studies in general to increase their knowledge about the teachings of ‘Abd al-Qadir al-Jilani.

  11. Oxidation Behaviour of Sputtered Ni-3Cr-20Al Alloy

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The oxidation behavior of sputtered Ni-3Cr-20Al coating at 900°C in air was investigated. A dense Al2O3 layer was formed on the sputtered Ni-3Cr-20Al coating after 200 h oxidation.However, owing to the segregation of Ni3Al during oxidation Focess at high temperature, the spinel NiAl2O4 was also formed in the Al2O3 layer. It was found that the formation of NiAl2O4had no detrimental effect on the oxidation resistance of the sputtered Ni-3Cr-20Al coating due to the excellent adhesion shown by the Al2O3 and NiAl2O4 complex oxide scale.

  12. Environmental embrittlement of intermetallic compounds in Fe-Al alloys

    Institute of Scientific and Technical Information of China (English)

    张建民; 张瑞林; S.H.YU; 余瑞璜

    1996-01-01

    First,it is proposed that hydrogen atoms occupy the interstitial sites in Fe3Al and FeAl.Then the environmental embrittlement of intermetallic compounds in Fe-Al alloys is studied in the light of calculated valence electron structures and bond energy of Fe3Al and FeAl containing hydrogen atoms.From the analyses it is found that the states of metal atoms will change,in which more lattice electrons will become covalent electrons to bond with hydrogen atoms when the atomic hydrogen diffuses into the intermetallic compounds in Fe-Al alloys,which will result in the decrease of local metallicity in Fe3Al and FeAl.Meanwhile,it is found that the crystal will easily cleave since solute hydrogen bonds with metal atoms and severely anisotropic bonds form.As a conclusion,these factors result in the environmental embrittlement of Fe3Al and FeAl.

  13. Gate length scaling effect on high-electron mobility transistors devices using AlGaN/GaN and AlInN/AlN/GaN heterostructures.

    Science.gov (United States)

    Liao, S Y; Lu, C C; Chang, T; Huang, C F; Cheng, C H; Chang, L B

    2014-08-01

    Compared to AlGaN/GaN HEMT with 0.15 μm T-gate length, the AlInN/AlN/GaN one exhibits much higher current density and transconductance of 1558 mA/mm at Vd = 2 V and 330 mS/mm, respectively. The high extrinsic ft and fmax of 82 GHz and 70 GHz are extracted from AlInN/AlN/GaN HEMT. Besides, we find that the transconductance roll-off is significant in AlGaN/GaN, but largely improved in AlInN/AlN/GaN HEMT, suggesting that the high carrier density and lattice-matched epitaxial heterostructure is important to reach both large RF output power and high operation frequency, especially for an aggressively gate length scaling.

  14. The Formation of γ—AlON Spinel in the Reaction of Al2O3—AlN—MgO System

    Institute of Scientific and Technical Information of China (English)

    LIYawei; YUANRunzhang; 等

    1997-01-01

    The stabilization of γ-aluminium oxyni-tride spinel(γ-AlON) has been investigated by addition of MgO,MgAl2O4,etc.,in reaction process.The results indicated that there are wider solid solution areas near ,Al2O3-rich side in AlN-Al2O3-MgO ternary systems,The content of stabilized AlON phase in samples is related to heating temperatures,additives,etc.The lattice parameters of their AlON phases could be well describedby the equation: a0=0.7900+0.0375[MgO]+0.015[AlN](nm)

  15. Properties of porous FeAlO/FeAl ceramic matrix composite influenced by mechanical activation of FeAl powder

    Indian Academy of Sciences (India)

    V Usoltsev; S Tikhov; A Salanov; V Sadykov; G Golubkova; O Lomovskii

    2013-12-01

    Porous ceramic matrix composites FeAlO/FeAl with incorporated metal inclusions (cermets) were synthesized by pressureless method, which includes hydrothermal treatment of mechanically alloyed FeAl powder followed by calcination. Their main structural, textural and mechanical features are described. Variation of FeAl powder alloying time results in non-monotonous changes of the porosity and mechanical strength. Details of the cermet microstructure and its relation to the mechanical properties are discussed.

  16. ALS1 and ALS3 gene expression and biofilm formation in Candida albicans isolated from vulvovaginal candidiasis

    Directory of Open Access Journals (Sweden)

    Shahla Roudbarmohammadi

    2016-01-01

    Conclusion: The results attained indicated that there is an association between the expression of ALS1 and ALS3 genes and fluconazole resistance in C. albicans. A considerable percent of the isolates expressing the ALS1 and ALS3 genes may have contributed to their adherence to vagina and biofilm formation.

  17. Spatial and temporal mapping of Al and AlO during oxidation in pulsed laser ablation of LaAlO3

    NARCIS (Netherlands)

    Orsel, K.; Groenen, R.; Bastiaens, H.M.J.; Koster, G.; Rijnders, G.; Boller, K-J.

    2013-01-01

    We present the first spatio-temporal mapping of two simultaneously present species in a plasma used for pulsed laser deposition. We apply laser induced fluorescence spectroscopy (LIF) to map ground state populations of Al and AlO in plasma plumes generated by ablation of LaAlO3 in an O2 or Ar atmosp

  18. The Byzantines in Medieval Arabic Poetry: Abu Firas’ "Al-Rumiyyat" and the Poetic Responses of al-Qaffal and Ibn Hazm to Nicephore Phocas’ "Al-Qasida al-Arminiyya al-Malʿuna" (The Armenian Cursed Ode

    Directory of Open Access Journals (Sweden)

    Nizar F. HERMES

    2009-10-01

    Full Text Available Up until the Crusades, it was al-Rūm who were universally seen by Arab writers and Arab poets in particular as the Other par excellence. Nowhere is this more conspicuous than in the sub-genre of Al-Rūmiyyat (poems about the Byzantines, namely as found in the Rūmiyyat of Abu Firas al-Hamdani(d.968, and in the poetic responses of al-Qaffal(d. 946 and Ibn Hazm(d. 1064 to what was described by several medieval Muslim chronicles as Al-Qasida al-Arminiyya al-Malʿuna (The Armenian Cursed Ode. By exploring the forgotten views of the Byzantines in medieval Arabic poetry, this article purports to demonstrate that contrary to the impression left after reading Edward Said’s groundbreaking Orientalism: Western Conceptions of the Orient (1978 and other postcolonial studies, Orientals have not existed solely to be ‘orientalized’. Perhaps even before this came to be so, they too had ‘occidentalized’ their Euro-Christian Other(s in a way that mirrored in reverse the subject/object relationship described as Orientalism.

  19. Fabrication of high-quality submicron Nb/Al-AlOx/Nb tunnel junctions

    Institute of Scientific and Technical Information of China (English)

    Yu Hai-Feng; Cao Wen-Hui; Zhu Xiao-Bo; Yang Hai-Fang; Yu Hong-Wei; Ren Yu-Feng; Gu Chang-Zhi; Chen Geng-Hua; Zhao Shi-Ping

    2008-01-01

    Nb/Al-AlOx/Nb tunnel junctions are often used in the studies of macroscopic quantum phenomena and supercon-ducting qubit applications of the Josepheon devices. In this work, we describe a convenient and reliable process using electron beam lithography for the fabrication of high-quality, submicron-sized Nb/Al-AlOx/Nb Josephson junctions.The technique follows the well-known selective Nb etching process and produces high-quality junctions with Vm=100 mV at 2.3 K for the typical critical current density of 2.2 kA/cm2, which can be adjusted by controlling the oxygen pressure and oxidation time during the formation of the tunnelling barrier. We present the results of the temperature depen-dence of the sub-gap current and in-plane magnetic-field dependence of the critical current, and compare them with the theoretical predictions.

  20. Evolutions during synthesis of Al-AlN-nanostructured composite powder by mechanical alloying

    Energy Technology Data Exchange (ETDEWEB)

    Abdoli, H. [Department of Materials Science and Engineering, Sharif University of Technology, P.O. Box 11365-9466, Azadi Avenue, 14588 Tehran (Iran, Islamic Republic of)], E-mail: habdoli@mehr.sharif.edu; Salahi, E. [Ceramic Department, Materials and Energy Research Center (MERC), P.O. Box 31787-316, Karaj (Iran, Islamic Republic of); Farnoush, H.; Pourazrang, K. [Department of Materials Science and Engineering, Sharif University of Technology, P.O. Box 11365-9466, Azadi Avenue, 14588 Tehran (Iran, Islamic Republic of)

    2008-08-11

    High-energy milling technique was used to synthesize Al-10 wt.%AlN-nanostructured composite powder in a planetary ball-mill under argon atmosphere up to 25 h. To show the role of AlN particles, process was conducted for monolithic aluminum. The changes in powder characteristics were investigated by time. Microstructure of powders was studied after different milling times by scanning electron microscope (SEM). The morphological evolutions showed that relative equiaxed powder could be synthesized after 25 h milling. Structural analysis was performed by X-ray diffraction method (XRD) to determine the grain sizes and lattice strain. Furthermore, particle size analysis (PSA) revealed the distribution curvatures. The compressibility behavior of milled powders was studied at different compaction pressures which involve the rearrangement and plastic deformation stages. The modified Heckel equation was used to consider the pressure effect on yield strength as well as reinforcing role of hard AlN particles.

  1. Effect of partial melting on superplasticity ofAlNp/6061Al composite

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    AlN particulate reinforced 6061 aluminum alloy composite was fabricated by powder metallurgy method and hot-rolled after extrusion. Tensile strength and elongation at elevated temperature were measured by tensile test at initial strain rates between 10-2 s-1 and 100 s-1. The AlNp/6061Al composite exhibits an m-value of 0.42 and a maximum elongation of 450% at 863?K. Differential scanning calorimeter was used to ascertain the possibility of any partial melting in the vicinity of optimum superplastic temperature. Partial melting resulting from solute segregation at interfaces has much influence on superplasticity of the composite. It is postulated that AlNp/matrix interface sliding occurs along with grain boundary in superplastic deformation.

  2. Characterization of Al30 in commercial poly-aluminum chlorohydrate by solid-state (27)Al NMR spectroscopy.

    Science.gov (United States)

    Phillips, Brian L; Vaughn, John S; Smart, Scott; Pan, Long

    2016-08-15

    Investigation of commercially produced hydrolysis salts of aluminum by solid-state (27)Al NMR spectroscopy and size-exclusion chromatography (SEC) reveals well-defined and distinct Al environments that can be related to physicochemical properties. (27)Al MAS and MQ-MAS NMR spectroscopic data show that the local structure of the solids is dominated by moieties that closely resemble the Al30 polyoxocation (Al30O8(OH)56(H2O)26(18+)), accounting for 72-85% of the total Al. These Al30-like clusters elute as several size fractions by SEC. Comparison of the SEC and NMR results indicates that the Al30-like clusters includes intact isolated clusters, moieties of larger polymers or aggregates, and possibly fragments resembling δ-Al13 Keggin clusters. The coagulation efficacy of the solids appears to correlate best with the abundance of intact Al30-like clusters and of smaller species available to promote condensation reactions. PMID:27232539

  3. Structure of molten Al-Si alloys

    International Nuclear Information System (INIS)

    The temperature variation of the structure and microstructure of molten eutectic Al1-xSix alloys (x = 0.122 and 0.20) have been studied by neutron diffraction and small-angle neutron scattering (SANS), as well as measurements performed on pure liquid Al. All measurements have been performed at five temperatures in a heating-cooling loop. The SANS results unambiguously show that for the eutectic alloy (x = 0.122) the microstructure changes with increasing temperature in a partly reversible way while for the hypereutectic (x = 0.20) alloy the change is almost completely irreversible. This change in microstructure also manifests itself in the shape of the static structure factor S(Q)

  4. Status of the AlCap experiment

    CERN Document Server

    Litchfield, R Phillip

    2015-01-01

    The AlCap experiment is a joint project between the COMET and Mu2e collaborations. Both experiments intend to look for the lepton-flavour violating conversion $\\mu + A \\rightarrow e + A$, using tertiary muons from high-power pulsed proton beams. In these experiments the products of ordinary muon capture in the muon stopping target are an important concern, both in terms of hit rates in tracking detectors and radiation damage to equipment. The goal of the AlCap experiment is to provide precision measurements of the products of nuclear capture on Aluminium, which is the favoured target material for both COMET and Mu2e. The results will be used for optimising the design of both conversion experiments, and as input to their simulations. Data was taken in December 2013 and is currently being analysed.

  5. Ni{sub 3}Al technology transfer

    Energy Technology Data Exchange (ETDEWEB)

    Sikka, V.K.; Viswanathan, S.; Santella, M.L. [Oak Ridge National Lab., TN (United States)] [and others

    1997-04-01

    Ductile Ni{sub 3}Al and Ni{sub 3}Al-based alloys have been identified for a range of applications. These applications require the use of material in a variety of product forms such as sheet, plate, bar, wire, tubing, piping, and castings. Although significant progress has been made in the melting, casting, and near-net-shape forming of nickel aluminides, some issues still remain. These include the need for: (1) high-strength castable composition for many applications that have been identified; (2) castability (mold type, fluidity, hot-shortness, porosity, etc.); (3) weld reparability of castings; and (4) workability of cast or powder metallurgy product to sheet, bar, and wire. The four issues listed above can be {open_quotes}show stoppers{close_quotes} for the commercial application of nickel aluminides. This report describes the work completed to address some of these issues during FY 1996.

  6. Structure of molten Al-Si alloys

    Energy Technology Data Exchange (ETDEWEB)

    Dahlborg, U. [CNRS, Ecole des Mines, Nancy, France; Besser, M. [Ames Laboratory; Calvo-Dahlborg, M. [CNRS, Ecole des Mines, Nancy, France; Cuello, G. [Institut Laue-Langevin (ILL); Dewhurst, C. D. [Institut Laue-Langevin (ILL); Kramer, Matthew J. [Ames Laboratory; Morris, James R [ORNL; Sordelet, Daniel [Ames Laboratory

    2007-01-01

    The temperature variation of the structure and microstructure of molten eutectic Al{sub 1-x}Si{sub x} alloys (x = 0.122 and 0.20) have been studied by neutron diffraction and small-angle neutron scattering (SANS), as well as measurements performed on pure liquid Al. All measurements have been performed at five temperatures in a heating-cooling loop. The SANS results unambiguously show that for the eutectic alloy (x = 0.122) the microstructure changes with increasing temperature in a partly reversible way while for the hypereutectic (x = 0.20) alloy the change is almost completely irreversible. This change in microstructure also manifests itself in the shape of the static structure factor S(Q).

  7. Antiferromagnetic behaviour of Tb2Al alloy

    Science.gov (United States)

    Rojas, D. P.; André, G.; Rodríguez Fernández, J.; Sánchez Marcos, J.; Fernández Barquín, L.; Echevarria, C.

    2011-10-01

    The structural, thermal and magnetic properties ol the Tb2Al alloy have been investigated by AC/DC magnetic susceptibility, specific heat, X-ray and neutron diffraction measurements. DC and AC-magnetic susceptibility results are consistent with an AFM order at TN = 52 K. The specific heat data show a lambda anomaly associated to the magnetic transition with a peak at 52 K (cord = 99 J/molTbK). The analysis of thermodiffractograms of neutron diffraction patterns indicates that, below the ordering temperature, the magnetic reflections can be indexed with a commensurate lattice related to the crystallographic cell (Pmna) by a propagation vector k = (1/2, 1/2, 1/2). The results are compared with those reported for other magnetic rare earth alloys of R2Al-type (with R = Nd, Gd and Dy).

  8. Antiferromagnetic behaviour of Tb2Al alloy

    International Nuclear Information System (INIS)

    The structural, thermal and magnetic properties ol the Tb2Al alloy have been investigated by AC/DC magnetic susceptibility, specific heat, X-ray and neutron diffraction measurements. DC and AC-magnetic susceptibility results are consistent with an AFM order at TN = 52 K. The specific heat data show a lambda anomaly associated to the magnetic transition with a peak at 52 K (cord = 99 J/molTbK). The analysis of thermodiffractograms of neutron diffraction patterns indicates that, below the ordering temperature, the magnetic reflections can be indexed with a commensurate lattice related to the crystallographic cell (Pmna) by a propagation vector k = (1/2, 1/2, 1/2). The results are compared with those reported for other magnetic rare earth alloys of R2Al-type (with R = Nd, Gd and Dy).

  9. Ni{sub 3}Al technology transfer

    Energy Technology Data Exchange (ETDEWEB)

    Sikka, V.K.; Santella, M.L.; Alexander, D.J. [Oak Ridge National Laboratory, TN (United States)] [and others

    1995-05-01

    Ductile Ni{sub 3}Al and Ni{sub 3}Al-based alloys have been identified for a range of applications. These applications require the use of material in a variety of product forms such as sheet, plate, bar, tubing, piping, and castings. Although significant progress has been made in the melting, casting, and near-net-shape forming of nickel aluminides, some issues still remain. These include the need for (1)high-strength castable composition for turbochargers, furnace furniture, and hot-die applications; (2) castability (fluidity, hot-shortness, porosity, etc.); (3) weld reparability of castings; and (4) hot fabricability of cast ingots. All of the issues listed above can be {open_quotes}show stoppers{close_quotes} for the commercial application of nickel aluminides. This report describes work completed to address some of these issues during the fourth quarter of FY 1994.

  10. [Communication with ALS patients: neurosurgical approach].

    Science.gov (United States)

    Yoshimine, Toshiki; Yanagisawa, Takufumi; Sawada, Jin-Ichi; Hazama, Takanori; Mochizuki, Hideki; Hirata, Masayuki

    2013-01-01

    By progression of the disease, motor neurons degenerate in patients with amyotrophic lateral sclerosis (ALS) eventually lose nearly all voluntary muscles in the body. They are awake and aware but cannot move or communicate (locked-in state). Since the function of the brain is preserved, one possible measure to support their communication is to interpret their motor intention by decoding (deciphering) brain signals and present it with external devices. This technology called "brain-machine interface (BMI)" is now close to clinical use in Japan and USA.In our system, we record electrocorticogram (ECoG) obtained with subudural electrodes during their motor imagery, decode it and determine the movement they intended. So far, one patient of ALS with severe paralysis, implanted with this electrodes, successfully operated the PC communication tool only by thinking.

  11. Léxico relativo al vestuario infantil

    OpenAIRE

    Torres Villaseñor, Hermila E.; Centro de Lingüística Hispánica, IIFL, UNAM

    2013-01-01

    Con base en el Cuestionario preparado por la Comisión de Lingüísticay Dialectología Iberoamericanas para el estudio del españolc ontemporáneo, preparé un cuestionario más amplio, con el cual he llevado a cabo una investigación sobre el léxico referente al vestido, según se emplea actualmente en la ciudad de México. Presento aquí los resultados de mi estudio en lo que respecta, únicamente, al vestuario de los niños menores de un año. Toda ladocumentación fue proporcionada por doce informantes ...

  12. Forging of FeAl intermetallic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Flores, O.; Juarez, J.; Campillo, B.; Martinez, L. [UNAM, Cuernavaca (Mexico). Lab. de Cuernavaca; Schneibel, J.H. [Oak Ridge National Lab., TN (United States)

    1994-09-01

    Much activity has been concentrated on the development of intermetallic compounds with the aim of improving tensile ductility, fracture toughness and high notch sensitivity in order to develop an attractive combination of properties for high and low temperature applications. This paper reports experience in processing and forging of FeAl intermetallic of B2 type. During the experiments two different temperatures were employed, and the specimens were forged after annealing in air, 10{sup {minus}2} torr vacuum and argon. From the results it was learned that annealing FeAl in argon atmosphere prior to forging resulted in better deformation behavior than for the other two environments. For the higher forging temperature used in the experiments (700C), the as-cast microstructure becomes partially recrystallized.

  13. Communication Support for People with ALS

    Directory of Open Access Journals (Sweden)

    David Beukelman

    2011-01-01

    Full Text Available Almost all people with amyotrophic lateral sclerosis (ALS experience a motor speech disorder, such as dysarthria, as the disease progresses. At some point, 80 to 95% of people with ALS are unable to meet their daily communication needs using natural speech. Unfortunately, once intelligibility begins to decrease, speech performance often deteriorates so rapidly that there is little time to implement an appropriate augmentative and alternative communication (AAC intervention; therefore, appropriate timing of referral for AAC assessment and intervention continues to be a most important clinical decision-making issue. AAC acceptance and use have increased considerably during the past decade. Many people use AAC until within a few weeks of their deaths.

  14. Structure formation of AlMg2-AlN composite cast in electromagnetic field

    OpenAIRE

    M. Cholewa; M. Staszewski; M. Sozańska; B. Formanek

    2007-01-01

    Purpose: Basic material concept, technology and some results of studies on aluminum matrix composite with dispersive aluminum nitride reinforcement was shown. Studied composites were manufactured with use f ex-situ technique and powder metallurgy.Design/methodology/approach: Aluminum nitride powder was manufactured in process of self-evolving high-temperature synthesis SHS. Composite powder Al-AlN was obtained using mechanical alloying. Composite castings were manufactured in stir casting pro...

  15. HYDROGEN ADSORPTION ON β-TiAl (001) AND Ni/TiAl (001) SURFACES

    OpenAIRE

    A. A. KARIM MUBARAK; MAHMOUD ALELAIMI

    2014-01-01

    In this paper, we present first principles calculations of the energetic, electronic and magnetic properties of the variant termination of TiAl (001) and Ni/TiAl (001) surfaces with and without hydrogen atoms. The calculations have been performed within the density functional theory using full-potential linearized augmented plane wave method. The generalized gradient approximation (GGA) is utilized as the exchange-correlation energy. The octahedral site is the stable absorption site of H atom...

  16. Ni-Al and NiO-Al Composite Coatings by Combustion-Assisted Flame Spraying

    OpenAIRE

    Galina Xanthopoulou; Amalia Marinou; George Vekinis; Aggeliki Lekatou; Michalis Vardavoulias

    2014-01-01

    A new, cost-efficient and on-site-applicable thermal spraying process for depositing NiAl metallic overlay or bond-coat coatings for high temperature applications by synthesizing the desired intermetallic phases in-flight during oxy-acetylene flame spraying is presented. Base-metal powders were used for spraying and, by adjusting the spraying conditions, excellent NiAl-based coatings were achieved on various substrates, including mild steel, stainless steel and aluminium alloys. Expensive, pr...

  17. An Epidemiological Study of Cutaneous Leishmaniasis in Al-Jabal Al-Gharbi, Libya

    OpenAIRE

    Abdellatif, Manal Z. M.; El-Mabrouk, Khamis; Ewis, Ashraf A.

    2013-01-01

    Cutaneous leishmaniasis (CL) is an endemic parasitic infection in the Mediterranean region, including Libya and its Al-jabal Al-gharbi province. We aimed at studying the occupational relevance as well as other epidemiological aspects of CL. We investigated 140 CL cases who attended at Gharyan outpatient polyclinic during a period of 6 months in 2009. CL infection was clinically diagnosed and confirmed by demonstration of Leishmania parasites on smears from lesions. Our findings showed that ma...

  18. Magnetism of UPtAl and UIrAl; LDA+U calculations

    Energy Technology Data Exchange (ETDEWEB)

    Rusz, Jan [Department of Electronic Structures, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 5, 121 16 Prague 2 (Czech Republic)]. E-mail: rusz@mag.mff.cuni.cz; Divis, Martin [Department of Electronic Structures, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 5, 121 16 Prague 2 (Czech Republic)

    2005-04-15

    We report on electronic structure calculations of UPtAl and UIrAl ternary uranium based intermetallic compounds. Calculations were performed in the framework of density functional theory using LDA+U exchange correlation potential. Full relaxation of U and J parameters was performed with the aim of obtaining correct total magnetic moments on uranium site. These parameters are then used in subsequent analysis of magnetic moments (including spin and orbital components) and hybridization effects.

  19. Response to de la Iglesia et al.

    Science.gov (United States)

    Yetish, Gandhi; Kaplan, Hillard; Gurven, Michael; Wood, Brian; Pontzer, Herman; Manger, Paul R; Wilson, Charles; McGregor, Ronald; Siegel, Jerome M

    2016-04-01

    We wish to respond to the commentary of de la Iglesia et al. [1]. Studies comparing sleep in different communities have different goals. One frequent goal has been to determine how sleep is affected by manipulating specific 'modern' conditions. Many studies have investigated the effect of artificial light and electronic entertainment. Such studies have clearly shown that light, particularly blue light, delays sleep onset [2]. Studying the effect of artificial light on sleep was not a goal of our study.

  20. Globale Entwikclung als Lernbereich in den Naturwissenschaften

    OpenAIRE

    Härtig, Hendrik; Bernholt, Sascha; Schroeter, Burkhard

    2014-01-01

    Mit dem Orientierungsrahmen für den Lernbereich Globale Entwicklung wurden Anregungen gegeben, die Themen nachhaltige Entwicklung und globale Entwicklung im Unterricht in allen Schulfächern aufzugreifen. Die drei naturwissenschaftlichen Schulfächer Biologie, Chemie und Physik haben sich bislang sehr unterschiedlich auf das Thema eingelassen. In der Biologiedidaktik finden sich sowohl Forschungsarbeiten als auch Unterrichtsvorschläge; für Chemie und insbesondere Physik existieren hingegen nur ...

  1. Thaghut dalam Al-Qur’an

    Directory of Open Access Journals (Sweden)

    Laila Sari Masyhur

    2012-12-01

    Full Text Available Tulisan berikut membahas konsep thâghût dalam al-Qur’an dengan menggunakan pendekatan tafsir tematik. Term thâghût berasal dari akar kata thaghâ yang secara bahasa berarti melanggar batas, berbuat sewenang-wenang, kejam atau menindas, melebihi ketentuan yang ada, meninggi dan melampaui batas dalam hal pengingkaran. Penulis menelusuri ayat-ayat al-Quran yang berbicara topik thâghût, hasilnya menemukan bahwa dalam al-Qu’ran kata ini dengan berbagai derivasinya (isytiqaq diulang sebanyak 39 kali yang tersebar dalam 39 ayat dan 27 surat. Dilihat dari segi struktur atau bentuk pengungkapan, term thâghût yang tersebar di dalam al-Qur’an tersebut setidaknya muncul dalam lima bentuk kata jadian (isytiqaq yang masing-masing implikasi makna yang berbeda-beda. Tulisan berikut membahas sedikitnya sembilan macam pengungkapan thâghût dengan berbagai pemaknaan dengan tekanan yang beragam, seperti misalnya anjuran untuk tidak mempercayai thâghût; peringatan bahwa thâghût menuntun manusia pada kekufuran; mempersekutukan Allah dengan mengimani thâghût; pemberitaan tentang orang-orang yang berhukum pada thâghût; orang-orang yang berperang di jalan thâghût; balasan Allah terhadap penyembah thâghût; perintah menghindari penyembahan thâghût; kabar gembira bagi yang menghindari penyembahan thâghût; dan faktor-faktor yang membuat manusia bekerjasama dengan thâghût. Elaborasi dari topik-topik tersebut bermaksud untuk menegaskan larangan Islam terhadap thâghût dan hal-hal yang berkaitan dengannya.

  2. Psychosocial adjustment to ALS: a longitudinal study

    Directory of Open Access Journals (Sweden)

    Tamara eMatuz

    2015-09-01

    Full Text Available For the current study the Lazarian stress-coping theory and the appendant model of psychosocial adjustment to chronic illness and disabilities (Pakenham 1999 has shaped the foundation for identifying determinants of adjustment to ALS. We aimed to investigate the evolution of psychosocial adjustment to ALS and to determine its long-term predictors. A longitudinal study design with four measurement time points was therefore, used to assess patients’ quality of life, depression, and stress-coping model related aspects, such as illness characteristics, social support, cognitive appraisals and coping strategies during a period of two years. Regression analyses revealed that 55% of the variance of severity of depressive symptoms and 47% of the variance in quality of life at T2 was accounted for by all the T1 predictor variables taken together. On the level of individual contributions, protective buffering and appraisal of own coping potential accounted for a significant percentage in the variance in severity of depressive symptoms, whereas problem management coping strategies explained variance in quality of life scores. Illness characteristics at T2 did not explain any variance of both adjustment outcomes. Overall, the pattern of the longitudinal results indicated stable depressive symptoms and quality of life indices reflecting a successful adjustment to the disease across four measurement time points during a period of about two years.Empirical evidence is provided for the predictive value of social support, cognitive appraisals, and coping strategies, but not illness parameters such as severity and duration for adaptation to ALS. The current study contributes to a better conceptualization of adjustment, allowing us to provide evidence-based support beyond medical and physical intervention for people with ALS.

  3. Response to de la Iglesia et al.

    Science.gov (United States)

    Yetish, Gandhi; Kaplan, Hillard; Gurven, Michael; Wood, Brian; Pontzer, Herman; Manger, Paul R; Wilson, Charles; McGregor, Ronald; Siegel, Jerome M

    2016-04-01

    We wish to respond to the commentary of de la Iglesia et al. [1]. Studies comparing sleep in different communities have different goals. One frequent goal has been to determine how sleep is affected by manipulating specific 'modern' conditions. Many studies have investigated the effect of artificial light and electronic entertainment. Such studies have clearly shown that light, particularly blue light, delays sleep onset [2]. Studying the effect of artificial light on sleep was not a goal of our study. PMID:27046810

  4. Complementary and Alternative Therapies in ALS

    OpenAIRE

    Bedlack, Richard S.; Joyce, Nanette; Carter, Gregory T.; Pagononi, Sabrina; Karam, Chafic

    2015-01-01

    Given the severity of their illness and lack of effective disease modifying agents, it is not surprising that most patients with ALS consider trying complementary and alternative therapies. Some of the most commonly considered alternative therapies include special diets, nutritional supplements, cannabis, acupuncture, chelation and energy healing. This chapter reviews these in detail. We also describe 3 models by which physicians may frame discussions about alternative therapies: paternalism,...

  5. Die globale Finanzkrise als Kumulation von Dilemmastrukturen

    OpenAIRE

    Münch, Philipp Alexander

    2012-01-01

    Was als sogenannte „Subprime-Krise“ auf dem US-Immobilienmarkt begann, hat sich zu einer sehr ernsten Finanz-, Banken- und Staatsschuldenkrise mit hohen Vermögensverlusten, Konkursen, sozialem Elend und beträchtlichen Bürden für Steuerzahler weiterentwickelt. Sogar die Existenz der Europäischen Währungsunion steht auf dem Spiel. Zahlreiche Analysebeiträge behandeln eine Vielzahl von Verursachungsfaktoren. In vorliegender Arbeit werden ganze Pyramiden von Dilemmastrukturen unterschiedlicher hi...

  6. Entspannung als Wirkfaktor in der manuellen Stimmbehandlung

    OpenAIRE

    Lehnert, B.; Schlasze, H; Siebertz, S; Neuschaefer-Rube, C

    2010-01-01

    Hintergrund: Verschiedene Studien sprechen für eine Wirksamkeit der Manuellen Therapien (z. B. Osteopathie) nicht nur bei der sog. "Zervikogenen Dysphonie", sondern auch bei hyperfunktionellen Dysphonien. Unsere klinische Erfahrung zeigt, dass Patienten eine manuelle Behandlung der HWS als sehr entspannend empfinden. Uns sind keine Arbeiten bekannt, die den Anteil dieser allgemeinen Entspannung am Behandlungserfolg der Manuellen Therapien untersuchen. Wir stellen eine erste Studie zum Vergle...

  7. Fabrication and Characterization of Al/p-CuInAlSe2 Thin Film Schottky Diodes

    Directory of Open Access Journals (Sweden)

    Usha Parihar

    2013-05-01

    Full Text Available Al/p-CuInAlSe2 polycrystalline schottky diodes fabricated by flash evaporation method were undertaken for their electrical analysis at room temperature. Diode parameters of the undertaken diodes were then derived from the current-voltage (I-V as well as capacitance-voltage (C-V characteristics. It has been observed that the schottky barrier height deduced from the room temperature I-V is lower to that obtained from the C-V characteristics and is attributed to the fact that I-V analysis includes both the image force and dipole lowering effects and is also reduced by the tunneling and leakage currents. The slope variation of the frequency dependent C – 2-V characteristics for the Al/p-CuInAlSe2 Schottky diode at varying frequency values from 50 kHz to 1 MHz suggests a large density of slow traps or interface states at the M-S junction. As emerging from the parameters values energy band diagram of Al and P-CuInAlSe2 has been reconstructed.

  8. Nanoindentation studies of ex situ AlN/Al metal matrix nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Fale, Sandeep; Likhite, Ajay; Bhatt, Jatin, E-mail: jatinbhatt@mme.vnit.ac.in

    2014-12-05

    Highlights: • Formation of in-situ phases nucleated on AlN particles strengthens the matrix. • Formation of in-situ phases increases with AlN content in nanocomposites. • Stronger in-situ phases results in increased hardness and modulus of elasticity. - Abstract: Nanocrystalline Aluminium nitride (AlN) powder is dispersed in different weight ratio in Aluminum matrix to fabricate metal matrix nanocomposite (MMNC) using ex situ melt metallurgy process. The synthesized Al–AlN nanocomposites are studied for phase analysis using high resolution scanning electron microscopy (FEG-SEM) and for hardness behavior using microindentation and nanoindentation tests. Quantitative analysis of the oxide phases is calculated from thermodynamic data and mass balance equation using elemental data obtained from energy dispersive spectroscopy (EDS) results. Role of oxide phases in association with AlN particles is investigated to understand the mechanical behavior of composites using nanoindentation tester. Load–displacement profile obtained from nanoindentation test reveals distribution of oxide phases along with AlN particle and their effect on indent penetration.

  9. Softening Kinetics in High Al and High Al-Nb-Microalloyed Steels

    Science.gov (United States)

    Pereda, B.; Aretxabaleta, Z.; López, B.

    2015-03-01

    Double-hit torsion tests were performed in order to study the effect of high Al levels (up to 2 wt.%) and Nb microalloying (up to 0.07 wt.%) on the static softening kinetics of 0.2%C-2%Mn steels. The addition of 1%Al leads to a delay in the softening kinetics due to solute-drag effect, equivalent to that exerted by 0.027%Nb. For the 2%Al steels, at temperatures below 1000 °C, γ → α phase transformation occurs after deformation, resulting in a larger retardation of the softening kinetics. At temperatures higher than 1000 °C, Nb in solid solution also contributes to the retardation of the static softening kinetics, and at lower temperatures NbC strain-induced precipitation leads to incomplete softening for the 1%Al steel, and to a complex interaction between softening, phase transformation, and NbC strain-induced precipitation for the 2%Al-Nb steels. The effect of Al on the static softening kinetics was quantified and introduced in a model developed in previous works for the prediction of the austenite microstructural evolution. In order to validate the results of the model, multipass torsion tests were carried out at conditions representative of hot strip and plate rolling mills. Model predictions show reasonable agreement with the results obtained at different deformation conditions.

  10. Preparation of Al- AlN Bonded Corundum Based Refractories by in-situ Reaction

    Institute of Scientific and Technical Information of China (English)

    ZHU Boquan; FANG Binxiang; ZHANG Wenjie

    2008-01-01

    The Al-AlN bonded corundum based refractories was synthesized with the starting materials of fused alu-mina and metallic aluminium in nitrogen atmosphere through in-situ reaction. The study indicated that with the addition of 14% metallic aluminium (13% of Al powder and 1% of Al fiber) , the material nitridized at 1 100 ℃ for 3 h has excellent physical properties. It is found that a massive quantity of AlN in the forms of both whiskers" and hexagon pellet particles is formed, and a large quantity of Al remained in the matrix. This multiple bonding system resulted in the excellent me-chanical properties of the material. It is also found that the hydration tendency of the prepared material is inhib-ited, and the material exhibited excellent thermal shock resistance. The nature of protective oxidation of the bonding system is characterized. Thus, this material may become a new candidate of carbon-free sliding plate material for continuous casting.

  11. FeAl and NbAl3 Intermetallic-HVOF Coatings: Structure and Properties

    Science.gov (United States)

    Guilemany, J. M.; Cinca, N.; Dosta, S.; Cano, I. G.

    2009-12-01

    Transition metal aluminides in their coating form are currently being explored in terms of resistance to oxidation and mechanical behavior. This interest in transition metal aluminides is mainly due to the fact that their high Al content makes them attractive for high-temperature applications. This is also a reason to study their resistance to wear; they may be suitable for use in applications that produce a lot of wear in aggressive environments, thus replacing established coating materials. In this study, the microstructure, microhardness, and wear and oxidation performance of FeAl and NbAl3 coatings produced by high-velocity oxy-fuel spraying are evaluated with two main aims: (i) to compare these two coating systems—a commonly studied aluminide (FeAl) and, NbAl3, an aluminide whose deposition by thermal spraying has not been attempted to date—and (ii) to analyze the relationship between their microstructure, composition and properties, and so clarify their wear and oxidation mechanisms. In the present study, the higher hardness of niobium aluminide coatings did not correlate with a higher wear resistance and, finally, although pesting phenomena (disintegration in oxidizing environments) were already known of in bulk niobium aluminides, here their behavior in the coating form is examined. It was shown that such accelerated oxidation was inevitable with respect to the better resistance of FeAl, but further improvements are foreseen by addition of alloying elements in that alloy.

  12. Model for metabolic resistance against ALS inhibitors

    Directory of Open Access Journals (Sweden)

    Richter, Otto

    2014-02-01

    Full Text Available Due to herbicide selection pressure metabolic resistance has evolved in many weed species. In this paper we analyse the interaction between the branched chain amino acid (BBC pathway and detoxifying pathways for herbicide breakdown. The four phase detoxification pathway of herbicides comprising the action of P450, GST, glycosyltransferase and ABC transporter is modelled by a system of coupled enzyme kinetic reactions represented by nonlinear differential equations. The herbicide under consideration inhibits the enzyme ALS, which is the key enzyme for the biosynthesis of branched amino acids. For the kinetics of ALS a Monod approach is employed with a binding site for the inhibitor. Synthetic and detoxification pathways are coupled. The model is used to study the production of branched amino acids under the action of ALS inhibitors for different structures and modes of action of the detoxification pathway. The model is capable of generating typical dose response curves and their shift in dependence of the activity pattern of the enzymes of the detoxification pathway of the inhibitor.

  13. Keanekaragaman dalam al-Qur’an

    Directory of Open Access Journals (Sweden)

    Muhammad Chirzin

    2011-04-01

    Full Text Available The diversity of race, language, class, and culture is a wealth; basically, it is a beautiful gift in this life. However, the reality is precesely the social conflict among the society. This article explores the issue of diversity contained in al Qur’an. Some of the key themes included: diversity as sunnatullah, diversity in unity, religious and ethnic diversity, and diversity of professions. Al Qur’an has mentioned several groups of religious believers and provided guidance association order among religious believers. Religious diversity certainly makes Muslim necessitates acknowledging and respecting other religion save Islam. Al Qur’an has mentioned also a variety of occupations based on interests, talents, expertise, and particular skills. The fragmentation and understanding diversity have caused by egoism and truth claiming of each group and individual, but no one has knowledge covering everything from different sides or corners. Above all knowledge is the Almighty owner off all knowledge. With feeling most true someone or group tends to feel the best and have the right to insult any others. That is the base of the dispute and spiritual decline. Mukmin has to preserve the noble character in association, and keep away from bad manner. Among mukmin must love each other and maintain good manners. Finally, this study is intended to promote the establishment of harmony, peace and happiness of living together.

  14. De la vigilancia convencional al monitoreo participativo

    Directory of Open Access Journals (Sweden)

    Jaime Breilh

    2003-01-01

    Full Text Available La necesidad de transformar el monitoreo de la salud de un instrumento funcional al sistema dominante de poder en una herramienta del poder colectivo, y de negociación del desarrollo de la salud laboral y el bienestar, implica la urgente transformación de la vieja vigilancia epidemiológica en un monitoreo participativo. Debe superarse el sistema convencional de información en salud, que observa fundamentalmente los "factores de enfermedad" y sus efectos mórbidos aislados, invisibilizando los procesos de determinación integrales. Este trabajo analiza el proceso de derrota de los derechos sociales y laborales, lo cual sitúa el desafío planteado en un escenario de profundo retroceso social y asalto a los derechos conquistados por los/as trabajadores/as en años de lucha. Con el propósito de esclarecer dicho argumento, al autor comienza contrastando los modelos de vigilancia clásicos, algunas propuestas transicionales, hasta arribar al monitoreo participativo. La aplicación de la categoría "perfil epidemiológico" permite sistematizar los dominios y dimensiones del monitoreo y establecer los sujetos sociales de esa mirada crítica e intercultural del pueblo sobre su salud, mediante la construcción de una matriz de procesos críticos.

  15. L'Hemisferic: Una ventana al mundo

    Directory of Open Access Journals (Sweden)

    Calatrava Valls, Santiago

    2000-12-01

    Full Text Available The "Hemisféric-Planetario" building is located in the center line East-West of the "Ciudad de las Artes y las Ciencias" complex, flanked by two rectangular lakes, in the north and in the south, respectively. In the East side we can find a promenade between the Museum and its south lake. Nevertheless its West side is virtual. and located in the area of the "Hermanos Marista 's" viaducto The building is visited, daily, by about 3.000 people, distributed between its 8 duties. The showing room holds 321 seats, four of those for wheel-chairs. The building has a possible room of 999 people (at the same time.El edificio Hemisféric-Planetarío está situado sobre el eje Este-Oeste del complejo de la Ciudad de las Artes y las Ciencias; está flanqueado por dos estanques rectangulares, al Norte y al Sur, respectivamente. Por el Este, un paseo limita la parcela con el Museo y su estanque Sur. El limite Oeste, sin embargo. es virtual y se encuentra en la proyección del viaducto de Hermanos Maristas. Este edificio es visitado diariamente por unos 3.000 personas, distribuyéndose en 8 funciones. La sala de proyección dispone de 321 butacas, con posibilidad de alojar 4 sillas de ruedas. La capacidad de acogida del edificio (al mismo tiempo es de 999 personas.

  16. Diet and dietetics in al-Andalus.

    Science.gov (United States)

    Salas-Salvadó, Jordi; Huetos-Solano, Maria D; García-Lorda, Pilar; Bulló, Mònica

    2006-08-01

    Al-Andalus society (711-1492) based its idea of health on the wisdom of Classical Greece, the Hippocratic-Galenic theories, as well as the Persian and Hindu cultures. The twelfth century in al-Andalus is considered to be the most prolific period for works of a scientific and technical nature. At the time, the main treatises on dietetics were written and this science reached its widest expression with such leading figures as Ibn Wāfīd, Avenzoar, Averroes and Maimonides, whose works revealed the first scientific knowledge on the nutritional processes of the human body. Diet was regarded as being essential for health and the prevention of disease. Dietary guidelines were written for different age groups, different body types and different seasons of the year. The amount of food to be ingested, the number of meals recommended and the order in which the food should be consumed were all issues that were discussed. A variety of foods were thought to have medicinal properties, some of which are known today. The diet in al-Andalus was varied and very probably made a substantial contribution to the origin of the present-day Mediterranean diet, rich in olive oil, wholemeal cereals, fruit and vegetables, fish, lamb, poultry, nuts and spices. We also find that many of the terms in current use in diet and agriculture are a living testimony to the Arabic influence, as are many of the dishes of our varied Mediterranean gastronomy.

  17. Studies on Al Kidirate and Kapoeta meteorites

    Energy Technology Data Exchange (ETDEWEB)

    Gismelseed, A.M. [Sudan Atomic Energy Commission, Khartoum (Sudan); Khangi, F. [Sudan Atomic Energy Commission, Khartoum (Sudan); Ibrahim, A. [Sudan Atomic Energy Commission, Khartoum (Sudan); Yousif, A.A. [Coll. of Science, Sultan Qaboos Univ., Alkhoud (Oman); Worthing, M.A. [Coll. of Science, Sultan Qaboos Univ., Alkhoud (Oman); Rais, A. [Coll. of Science, Sultan Qaboos Univ., Alkhoud (Oman); Elzain, M.E. [Coll. of Science, Sultan Qaboos Univ., Alkhoud (Oman); Brooks, C.K. [Coll. of Science, Sultan Qaboos Univ., Alkhoud (Oman); Sutherland, H.H. [Coll. of Science, Sultan Qaboos Univ., Alkhoud (Oman)

    1994-11-01

    Moessbauer spectroscopy (20-300 K), magnetic susceptibility measurements (77-350 K), scanning electron microscopy and X-ray diffraction experiments have been performed on two meteorite samples: one from an old fall (Kapoeta) and another from a very recent fall (Al Kidirate). The two specimens differ in their mineralogy. Chondrules appear to be absent in Kapoeta and it is probably a pyroxene-plagioclase achondrite with ferrohypersthene as the most abundant mineral. On the other hand, the Al Kidirate meteorite is an ordinary chondrite and the specimen consists of olivine, orthopyroxene, troilite and kamacite. The Moessbauer measurements confirm the above characterization, showing a paramagnetic doublet for the Kapoeta sample and at least two paramagnetic doublets and magnetic sextets for the Al Kidirate specimens. The former were assigned to Fe in pyroxene sites, while the latter was assigned to Fe in pyroxene, olivine, Fe-S and Fe-Ni alloys. The difference in the mineralogy of the two meteorites has also been reflected in the temperature-dependent magnetic susceptibility. The magnetization and the hyperfine interaction parameters will be discussed in relation to the mineralogy. (orig.)

  18. Thermodynamic properties and mixing thermodynamic parameters of Ba-Al, Mg-Al, Sr-Al and Cu-Al metallic melts

    Institute of Scientific and Technical Information of China (English)

    张鉴

    2004-01-01

    Application of equations of mixing thermodynamic parameters formulated on the basis of the coexistence theory of metallic melts in Ba-Al, Mg-Al, Sr-A1 and Cu-Al melts leads to fruitful results that not only the evaluated mass action concentrations agree well with the measured activities, but also the calculated mixing thermodynamic parameters are quite coincident with the experimental values. Moreover, the calculated mass action concentrations strictly obey the mass action law. The evaluated mixing thermodynamic parameters have very fine regularity: the mixing free energy is composed of standard free formation energies of all compounds and chemical potentials of all structural units at equilibrium; the mixing enthalpy consists of standard formation enthalpies of all compounds; the mixing entropy is composed of standard entropies of all compounds and configuration entropies of all structural units at equilibrium. As the equations of mixing thermodynamic parameters formulated are widely applicable to metallic melts involving compound formation, they can be used as the second practical criterion to determine whether thermodynamic models of metallic melts are correctly formulated.

  19. Structure analysis of Al cast alloy

    Directory of Open Access Journals (Sweden)

    L.A. Dobrzański

    2008-03-01

    Full Text Available Purpose: The developed design methodologies both the material and technological ones will make it possible to improve shortly the quality of materials from the light alloys in the technological process, and the automatic process flow correction will make the production cost reduction possible, and - first of all - to reduce the amount of the waste products.Design/methodology/approach: Castings were analysed in the paper of car engine blocks and heads from the Al-Si-Cu alloys of the AC-AlSi7Cu3Mg type fabricated with the “Cosworth” technological process. In this work the AC-AlSi7Cu3Mg alloy structure was investigated, of this alloy samples were cut of for structure analysis of the cylinder part as well of crankshaft of a fuel engine. The investigation show a difference in the (phase structure morphology as a result of cast cooling rate.Findings: On the quality of casting has influence the walls thickness of car engine elements’.Practical implications: In the metal casting industry, an improvement of component quality depends mainly on better control over the production parameters.Originality/value: The value of the applied methodology was to correct identify the casting effects that occurred during the casting process.

  20. Lower motor neuron dysfunction in ALS.

    Science.gov (United States)

    de Carvalho, Mamede; Swash, Michael

    2016-07-01

    In the motor system there is a complex interplay between cortical structures and spinal cord lower motor neurons (LMN). In this system both inhibitory and excitatory neurons have relevant roles. LMN loss is a marker of motor neuron disease/amyotrophic lateral sclerosis (MND/ALS). Conventional needle electromyography (EMG) does not allow LMN loss to be quantified. Measurement of compound muscle action potential (CMAP) amplitude or area, and the neurophysiological index, provide a surrogate estimate of the number of functional motor units. Increased motor neuronal excitability is a neurophysiological marker of ALS in the context of a suspected clinical and electrophysiological diagnosis. In the LMN system, fasciculation potentials (FPs) are the earliest changes observed in affected muscles, a feature of LMN hyperexcitability. Reinnervation is best investigated by needle EMG although other methods can be explored. Moreover needle EMG give information about the temporal profile of the reinnervation process, important ancillary data. Quantitative motor unit potential analysis is a valuable method of evaluating reinnervation. The importance of FPs has been recognized in the Awaji criteria for the electrodiagnosis of ALS, criteria that are a sensitive adjunct to the revised El Escorial criteria. Finally, functionality of LMN's, and perhaps excitability studies in motor nerves, aids understanding of the disease process, allowing measurement of potential treatment effects in clinical trials. Other investigational techniques, such as electrical impedance myography, muscle and nerve ultrasound, and spinal cord imaging methods may prove useful in future. PMID:27117334

  1. X-ray photoelectron spectroscopy and magnetism of AlDyNi, AlDyNi4 and AlDy3Ni8 compounds

    International Nuclear Information System (INIS)

    The electronic and magnetic properties of AlDyNi, AlDyNi4 and AlDy3Ni8 are studied using X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), static and dynamic magnetic measurements. The three compounds AlDyNi, AlDyNi4 and AlDy3Ni8 are single phases and crystallize in the Fe2P, CaCu5 and CeNi3 structure types, respectively. All the investigated compounds order ferromagnetically below the corresponding Curie temperatures. The Curie temperature and the magnetic moments are 25 K and 6 μB/f.u. for AlDyNi, 14 K and 6.9 μB/f.u. for AlDyNi4 and 22K and 19.2 μB/f.u. for AlDy3Ni8. At high temperature the magnetic susceptibility obey the Curie-Weiss law. The paramagnetic Curie temperature and the effective magnetic moments are 30K and 10.88 μB/f.u. for AlDyNi, 28 K and 10.94 μB/f.u. for AlDyNi4 and 18 K and 18.33 μB/f.u. for AlDy3Ni8. XPS valence band and Ni 2p spectra indicated the presence of small magnetic moment on Ni sites in AlDy3Ni8 and AlDyNi4, and a complete filling of Ni 3d band in AlDyNi.

  2. Al-Al2O3 core-shell composite by microwave induced oxidation of aluminium powder

    International Nuclear Information System (INIS)

    Microwave processing is gaining importance in the preparation of composite materials mainly because of its predominance in the improvement of uniformity for different phases formed. In the present study, commercial Al powder was heat treated using microwave radiation to synthesize Al-Al2O3 core-shell composite powder. The as received Al powder and the microwave heated Al powders were characterized by X-ray diffractometry (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray (EDX) analysis and zeta potential measurement. XRD data confirmed the formation of Al-Al2O3 composite. FTIR studies indicated the core-shell type Al-Al2O3 composite formation. SEM observations suggested the formation of Al-Al2O3 core-shell composite. TEM images, corresponding selected area electron diffraction (SAED) patterns and EDX analysis confirmed the Al-Al2O3 core-shell composite development. Zeta potential measurements also indicated that Al core particles were surrounded with Al2O3 shell.

  3. The atomic details of the interfacial interaction between the bottom electrode of Al/AlOx/Al Josephson junctions and HF-treated Si substrates

    Science.gov (United States)

    Zeng, L. J.; Krantz, P.; Nik, S.; Delsing, P.; Olsson, E.

    2015-04-01

    The interface between the Al bottom contact layer and Si substrates in Al based Josephson junctions is believed to have a significant effect on the noise observed in Al based superconducting devices. We have studied the atomic structure of it by transmission electron microscopy. An amorphous layer with a thickness of ˜5 nm was found between the bottom Al electrode and HF-treated Si substrate. It results from intermixing between Al, Si, and O. We also studied the chemical bonding states among the different species using energy loss near edge structure. The observations are of importance for the understanding of the origin of decoherence mechanisms in qubits based on these junctions.

  4. Some Maudu (Fabricated) Narrations in Tafsir Al-Dur Al-Manth‘ur (Sura Al-Nisa of the Holy Quran)

    OpenAIRE

    Nasrullah Khan; Janas Khan; Ziaullah Al-Azhari; Muhammad Ayaz; Abaad ur Rahman; Jannat Naeem Khan; Karim Dad

    2012-01-01

    “Tafseer Al-Dur Al-Man‘thur Fi Tafsir Al-Math‘ur“ is the commentary of the Holy Quran written by Jalal Al-Din Al-Suyuti. He was born in Cairo, Egypt in 849H/1445AH. He was a renowned scholar of his time having mastery in many fields of Islamic Studies like Quran, Hadith, fiqh and history. In the last days of his life, he got isolated himself from all the worldly affairs and concentrated on writing books. He wrote almost in every field of knowledge and authored nearly 600 books. He died in 911...

  5. Reciprocating Wear Behaviour of 7075Al/SiC and 6061Al/Al2O3 Composites: A study of Effect of Reinforcement, Stroke and Load

    OpenAIRE

    J. Lakshmipathy; B. Kulendran

    2014-01-01

    The wear behaviour comparison of Al/SiC and Al/Al2O3 composites prepared by stir casting technique is investigated to find out the effects of weight percentage of SiC/Al2O3, load and the number of strokes on a reciprocating wear testing machine. The MMC pins are prepared with different weight percentage of SiC and Al2O3 (10, 15 and 20 %). The tests are carried out with different load conditions (25, 50 and 75 N) and different number of strokes (420,780 and 1605 strokes). Wear surfaces of test...

  6. Aspectos biopsicosociales asociados al embarazo adolescente

    Directory of Open Access Journals (Sweden)

    Regina Cogollo Jiménez

    2012-12-01

    Full Text Available Introducción: El embarazo en la adolescencia, es un evento inesperado, sorpresivo. Este artículo establece la importancia de identificar los aspectos biopsicosociales asociados al embarazo adolescente en las embarazadas asistentes al programa de Control Prenatal de una Empresa Social del Estado de nivel 1 en Montería en 2009, para comprender las actitudes y los comportamientos asociados a esta etapa tan temprana. Materiales y Métodos: Es un estudio descriptivo, cuantitativo, de corte transversal. Población y muestra: 30 adolescentes embarazadas asistentes al Programa, el muestreo por conveniencia. Se utilizó la encuesta y la observación directa, previa autorización del Director de la empresa. Resultados: Caracterización de la población: predominó la edad de 15 a 19 años (adolescencia tardía, uniones libres, baja escolaridad debido a la deserción escolar, ingreso económico menor al salario mínimo legal vigente. Aspectos Biológicos: la menarquía a temprana edad (9 a 14 años, y en ella la mitad de los embarazos. La mayoría de los segundos embarazos terminaron en parto, la minoría en cesárea y aborto. La captación para los controles prenatales fue tardía, algunas no cumplieron con las citas programadas. Aspectos Psicológicos: inestabilidad con la pareja al enterarse del embarazo, tuvieron soporte familiar moral y económico, abandonaron sus estudios y presentaron malestares como estrés, depresión y tristeza. Aspectos Sociales: predominó la convivencia con la familia extensa. Hubo aceptación en el colegio y en los amigos. Discusión y Conclusiones: Se plantean estrategias para disminuir estos aspectos: elaboración de una cartilla sobre “Cuidado de la adolescente embarazada”, creación de espacios de reflexión, jornadas lúdicas educativas, entre otros. (Rev Cuid 2012; 3(3:385-93.Palabras clave: Embarazo en Adolescencia, Bienestar Materno, Atención Prenatal. (Fuente: De

  7. Studies of Al metabolism in animal by accelerator mass spectrometry

    Institute of Scientific and Technical Information of China (English)

    WangNa-Xiu; ZhuHan-Min; 等

    1997-01-01

    The correlation between Al metabolism and senile dementia in animal has been studied by AMS(accelerator mass spectrometry).Three groups of laboratory rats were fed with normal food.food with high Al content,and with enriched Ca and Mg together with high Al,respectively for six to eight months.Mapping test was made to recored th degree of wisdom degeneration.Half of the rats were sacrificed and Al contents in various organs were measured by atomic absorption spectroscopy.The rest were injected with 26Al,killed after 5,10,15,25,and 35d and 26Al contents measured by AMS.The distribution of Al as well as the correlation among the accumulation of 26Al,and the existed Al content and dementia was studied.

  8. High-efficiency of AlInGaN/Al(In)GaN-delta AlGaN quantum wells for deep-ultraviolet emission

    Science.gov (United States)

    Saidi, Hosni; Ridene, Said

    2016-10-01

    Band structure and optical gain properties of AlInGaN/AlInGaN-delta-AlGaN quantum wells for deep-ultraviolet light emitting and lasers diodes with wavelength λ ∼229 nm and TE-polarized optical gain peak intensity ∼1.7 times larger than the conventional AlInN-delta-GaN was proposed and investigated in this work. The active region is made up of 20 Å staggered Al0.89In0.03Ga0.08N/Al0.8In 0.01Ga0.19N layers with a 3 Å Al0.46Ga0.54N delta layer. The use of the quaternary AlInGaN well layer permits the independent control of the band gap and the lattice parameter, so that the internal electric field induced by polarizations can be reduced and interband transition energy increases. Therefore, we can predict that the optical performance of the AlInGaN-delta-AlGaN is more convenient for an emission in the deep-ultraviolet than that of the conventional AlInN-delta-GaN-based quantum wells.

  9. Chemical ordering and large tunnel magnetoresistance in Co2FeAl/MgAl2O4/Co2FeAl(001) junctions

    Science.gov (United States)

    Scheike, Thomas; Sukegawa, Hiroaki; Inomata, Koichiro; Ohkubo, Tadakatsu; Hono, Kazuhiro; Mitani, Seiji

    2016-05-01

    Epitaxial magnetic tunnel junctions (MTJs) with a Co2FeAl/CoFe (0.5 nm)/MgAl2O4/Co2FeAl(001) structure were fabricated by magnetron sputtering. High-temperature in situ annealing led to a high degree of B2-order in the Co2FeAl layers and cation order of the MgAl2O4 barrier. Large tunnel magnetoresistance (TMR) of up to 342% was obtained at room temperature (616% at 4 K), in contrast to the TMR ratio ( ≲ 160%) suppressed by the band-folding effect in Fe/cation-ordered MgAl2O4/Fe MTJs. The present study reveals that the high degree of B2-order and the resulting high spin polarization in the Co2FeAl electrodes enable us to bypass the band-folding problem in spinel barriers.

  10. Effect of nitrogen incorporation into Al-based gate insulators in AlON/AlGaN/GaN metal-oxide-semiconductor structures

    Science.gov (United States)

    Asahara, Ryohei; Nozaki, Mikito; Yamada, Takahiro; Ito, Joyo; Nakazawa, Satoshi; Ishida, Masahiro; Ueda, Tetsuzo; Yoshigoe, Akitaka; Hosoi, Takuji; Shimura, Takayoshi; Watanabe, Heiji

    2016-10-01

    The superior physical and electrical properties of aluminum oxynitride (AlON) gate dielectrics on AlGaN/GaN substrates in terms of thermal stability, reliability, and interface quality were demonstrated by direct AlON deposition and subsequent annealing. Nitrogen incorporation into alumina was proven to be beneficial both for suppressing intermixing at the insulator/AlGaN interface and reducing the number of electrical defects in Al2O3 films. Consequently, we achieved high-quality AlON/AlGaN/GaN metal-oxide-semiconductor capacitors with improved stability against charge injection and a reduced interface state density as low as 1.2 × 1011 cm-2 eV-1. The impact of nitrogen incorporation into the insulator will be discussed on the basis of experimental findings.

  11. Al-Ca and Al-Fe metal-metal composite strength, conductivity, and microstructure relationships

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyong June [Iowa State Univ., Ames, IA (United States)

    2011-01-01

    Deformation processed metal-metal composites (DMMC’s) are composites formed by mechanical working (i.e., rolling, swaging, or wire drawing) of two-phase, ductile metal mixtures. Since both the matrix and reinforcing phase are ductile metals, the composites can be heavily deformed to reduce the thickness and spacing of the two phases. Recent studies have shown that heavily drawn DMMCs can achieve anomalously high strength and outstanding combinations of strength and conductivity. In this study, Al-Fe wire composite with 0.07, 0.1, and 0.2 volume fractions of Fe filaments and Al-Ca wire composite with 0.03, 0.06, and 0.09 volume fractions of Ca filaments were produced in situ, and their mechanical properties were measured as a function of deformation true strain. The Al-Fe composites displayed limited deformation of the Fe phase even at high true strains, resulting in little strengthening effect in those composites. Al-9vol%Ca wire was deformed to a deformation true strain of 13.76. The resulting Ca second-phase filaments were deformed to thicknesses on the order of one micrometer. The ultimate tensile strength increased exponentially with increasing deformation true strain, reaching a value of 197 MPa at a true strain of 13.76. This value is 2.5 times higher than the value predicted by the rule of mixtures. A quantitative relationship between UTS and deformation true strain was determined. X-ray diffraction data on transformation of Al + Ca microstructures to Al + various Al-Ca intermetallic compounds were obtained at the Advanced Photon Source at Argonne National Laboratory. Electrical conductivity was measured over a range of true strains and post-deformation heat treatment schedules.

  12. Mechanism and kinetics analysis of AlN combustion synthesis

    Institute of Scientific and Technical Information of China (English)

    郑永挺; 张宇民; 赫晓东; 刘长青

    2004-01-01

    Mechanism of AlN combustion synthesis was studied by DSC analysis and "quenching" experiment of combustion wave. In preheating region, Al powder melted at 660 ℃ and became spherical because of surface tension. In reaction region, Al volatilized rapidly at 1 000 ℃ and Al vapor reacted with N2 to form AlN, which nucleated and grew on the surface of AlN formed precedently as a diluent. Based on the experiment analysis,kinetics equations and modeling were established. Analysis showed the dramatic effect of temperature, aluminum particle size and nitrogen pressure on the reaction speed.

  13. Accelerated corrosion behaviors of Zn, Al and Zn/15Al coatings on a steel surface: Pospešeno korozijsko obnašanje Zn, Al in Zn/15Al prekritij na površini jekla:

    OpenAIRE

    Cevher, Ozgur; Gulec, Ahmet; Turk, Ahmet; Ustel, Fatih; Yilmaz, Fevzi

    2011-01-01

    Zn, Al and Zn/15Al coatings can be produced in optimum conditions by the twin wire arc (TWEA) spraying technique. The coatings are used for corrosion protection in a variety of industrial applications. In this study, the accelerated corrosion behavior of Zn, Al and Zn/15Al coatings on a steel surface during the salt-spray testing period was investigated. The surfaces ofsteel coupons were coated with Zn, Al and Zn/15Al using the TWEA spray-deposition system. The corrosion test was performed in...

  14. Tailoring ultrafine grained and dispersion-strengthened Ti$_2$AlC/TiAl composite via a new fabrication route

    Indian Academy of Sciences (India)

    TAOTAO AI; QI YU; WENHU LI; XIANGYU ZOU; ZHIFENG DENG; XINQIANG YUAN

    2016-09-01

    In situ Ti$_2$AlC/TiAl composite was fabricated by hot-pressing method via the reaction system of Ti$_3$AlC$_2$ and Ti-Al pre-alloyed powders at low temperature of 1150$^{\\circ}$C. The composite mainly consisted of TiAl, Ti$_3$Al and Ti$_2$AlC phases. Fine Ti$_2$AlC particles were homogeneously distributed and dispersed in the matrix. Ti$_2$AlC played the significant role of deflecting and blunting the cracks and contributed to improve the mechanical properties of the composite. The Vickers hardness, flexural strength and fracture toughness were 6.2 GPa, $993.9\\pm 50.8$ MPa and $6.7\\pm 0.3$ MPa m$^{1/2}$, respectively.

  15. Ibn al-ʻArabī and Abū Yazīd al-Bistāmī

    OpenAIRE

    ABRAHAMOV, Binyamin

    2011-01-01

    Many Sufis appear in Ibn al-‛Arabī’s al-Futūhāt al-Makkiyya, a treatise in which the author puts forward his principal ideas. Abū Yazīd al-Bistāmī is mentioned in this work 143 times, more than any other Sufi. The present article seeks to examine Ibn al-‛Arabī’s attitude toward his Sufi predecessor by considering al-Bistāmi’s personality as it appears in Ibn al-‛Arabī, as well as Ibn al-‛Arabī’s views on al-Bistāmī’s Sufi practice, his presence as a model of moral conduct a...

  16. Fabrication and Properties of AlON Ceramics%AlON陶瓷的制备及性能

    Institute of Scientific and Technical Information of China (English)

    裴新美

    2001-01-01

    以Al粉和Al2O3为原料,用铝粉氮化反应烧结技术(RBAN)制备AlON 陶瓷.氮化产物为纳米尺度的AlN相,AlN纳米晶的高活性使得在1 600 ℃即合成了AlON相,该温度低于相图显示的合成温度(1 700 ℃).新生的细晶AlON相有利于低温烧结,1 750 ℃制备出致密的AlON、Al2O3-AlON陶瓷.

  17. The improvement of Al2O3/AlGaN/GaN MISHEMT performance by N2 plasma pretreatment

    Institute of Scientific and Technical Information of China (English)

    Feng Qian; Tian Yuan; Bi Zhi-Wei; Yue Yuan-Zheng; Ni Jin-Yu; Zhang Jin-Cheng; Hao Yue; Yang Lin-An

    2009-01-01

    This paper discusses the effect of N2 plasma treatment before dielectric deposition on the electrical performance of a Al2O3/AlGaN/GaN metal-insulator-semiconductor high electron mobility transistor (MISHEMT), with Al2O3deposited by atomic layer deposition. The results indicated that the gate leakage was decreased two orders of magnitude after the Al2O3/AlGaN interface was pretreated by N2 plasma. Furthermore, effects of N2 plasma pretreatment on the electrical properties of the AlGaN/Al2O3 interface were investigated by x-ray photoelectron spectroscopy measurements and the interface quality between Al2O3 and AlGaN film was improved.

  18. Urchin-like AlOOH nanostructures on Al microspheres grown via in-situ oxide template

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Jiaquan [Department of Materials Science and Engineering, University of California, Los Angeles, Los Angeles, CA 90095 (United States); Estruga, Marc [Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706 (United States); Chen, Lianyi [Department of Mechanical and Aerospace Engineering, University of California, Los Angeles, Los Angeles, CA 90095 (United States); Yahata, Brennan [Department of Materials Science and Engineering, University of California, Los Angeles, Los Angeles, CA 90095 (United States); Choi, Hongseok [Department of Mechanical Engineering, Clemson University, Clemson, SC 29634 (United States); Li, Xiaochun, E-mail: xcli@seas.ucla.edu [Department of Mechanical and Aerospace Engineering, University of California, Los Angeles, Los Angeles, CA 90095 (United States)

    2014-10-15

    Highlights: • We present a simple, scalable method to grow urchin-like AlOOH on Al microspheres. • Al{sub 2}O{sub 3} nanoparticles from the native oxide films and self-assemble to form templates. • Urchin-like nanostructures spontaneously form and growth on the Al{sub 2}O{sub 3} templates. - Abstract: Three dimensional (3D) metal oxide hydroxide nanostructures are highly desirable for numerous applications. Here, we present a simple, scalable method to grow urchin-like AlOOH nanostructures on the surface of Al microspheres. Al nanoparticles with native oxide film were melted in molten salts, forming an immiscible materials system. During ultrasonic processing of the mixture, emulsion of micro Al droplets occurs and Al{sub 2}O{sub 3} nanoparticles form from the native oxide films and self-assemble to form in-situ nanostructured templates on the surfaces of Al microspheres. When the solidified mixture of Al spheres and salt is exposed to water, urchin-like nanostructures spontaneously form on the Al microspheres due to a heterogeneous nucleation and growth of γ-AlOOH on the Al{sub 2}O{sub 3} templates. This work could be readily extended to other metals, providing a novel and scalable method for the fabrication of urchin-like metal oxide hydroxide nanostructures on metal microspheres.

  19. Effect of Al content on r-value and recrystallization texture of B-bearing Al-killed steel sheets

    Energy Technology Data Exchange (ETDEWEB)

    Funakawa, Y.; Inazumi, I.; Hosoya, Y. [NKK Corp., Hiroshima (Japan). Mater. and Process. Res. Center; Murayama, T.

    1998-10-01

    It has been demonstrated that boron (B) had a beneficial effect on the mechanical properties of continuously annealed Al-killed steel sheets. However, the effect of Al content on r-value in the B-bearing steels has not been well discussed yet. In this study, the effect of Al content on r-value and recrystallization texture formation was investigated for laboratory-melt B-bearing low C Al-killed steel sheets. The r-value of continuously annealed B-bearing steel increased with decreasing Al content under the same grain size. In the steels with lower Al (Al=0.005%) content, the carbide coarsening in hot-rolled sheet was more significant as compared to those with higher Al(Al=0.055%) content. The recrystallization temperature was lowered with decreasing Al content, and the development of left angle 111 right angle //ND components was accelerated while that of left angle 110 right angle //ND components was retarded. Since the increase in Al content accelerates AlN precipitation in hot-rolled sheets, B might remain as in solution and segregate to grain boundaries. On the other hand, the reduction in Al content causes preferential precipitation of BN in hot-rolled sheets. The improvement of r-value by reducing Al content in B-bearing low C steels was caused by the development of left angle 111 right angle //ND components which reduced by solute B. (orig.) 9 refs.

  20. As-cast microstructure of Al-Zn-Mg and Al-Zn-Mg-Cu alloys added erbium

    Institute of Scientific and Technical Information of China (English)

    MAO Jian-wei; JIN Tou-nan; XU Guo-fu; NIE Zuo-ren

    2005-01-01

    The effects of different contents of rare earth element, and erbium, on the as-cast microstructures of Al-6Zn-2Mg and Al-6Zn-2Mg-1.8Cu alloys were studied by optical microscopy, scanning electron microscopy, X-ray diffractometry, transmission electron microscopy and EDS analysis. The results show that the netlike structure of as-cast alloys can be remarkably refined, and the distance of dendritic structure decreases, with Er addition. However, the improvement results on Al-Zn-Mg-Cu are not better than that of Al-Zn-Mg. Er and Al can interact to form Al3Er phase, which is coherent with α(Al) matrix, with trace Er addition to the Al-Zn-Mg alloy. The refinement effect of Al-Zn-Mg alloys is familiar with the formation and precipitation of coherent Al3Er phases. The ternary compound AlCuEr, similar with AlCuSc phase, will form when Er is added to Al-Zn-Mg-Cu alloy, which suppresses the formation of Al3Er phase and doesn't solve in the following heat treatment.

  1. Hot Corrosion Performance of AlO-CrO/NiCoCrAlYTa and AlO/NiCoCrAlYTa Coatings Deposited by Atmospheric Plasma Spraying

    Science.gov (United States)

    Tao, Chong; Wang, Lei; Cheng, Nailiang; Hu, Hengfa; Liu, Yang; Song, Xiu

    2016-04-01

    AlO-CrO/NiCoCrAlYTa and AlO/NiCoCrAlYTa coatings were deposited on 316L stainless steel substrate using atmospheric plasma spraying, respectively, in order to improve the oxidation and corrosion resistance. The hot corrosion performance of the coatings at 700 and 900 °C were studied, and the detailed microstructures and phase composition of the coatings were analyzed using x-ray diffraction, scanning electron microscope with energy dispersive spectrometer, and transmission electron microscope. The results show that both coatings are structurally featured by slatted layers, consisting of amorphous phase, Cr2O3, Ni3Al, and Al2O3. The hot corrosion resistance of AlO-CrO/NiCoCrAlYTa coating is better than that of AlO/NiCoCrAlYTa coating. This improvement is attributed to lower porosity and more compact Cr2O3 in AlO-CrO/NiCoCrAlYTa coating which performs better than Al2O3 in blocking further inward progress of corrosion and oxidization.

  2. Refining Effect of Boron on Hypoeutectic Al-Si Alloys

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@Several concepts of the grain refinement mechanism of B on hypoeutectic Al-Si alloys have been adopted: the refining effect of B on the α-Al and eutectic Si with the different additions of Al-B master alloys made at 850℃ was investigated; and the Al-B master alloys formed under different temperature conditions have been studied to explore the morphologies of AlB2 particles;slowly cooled sample with addition of Al-B was made to explore the refinement mechanism. AlB master alloy can refine not only α-Al, but eutectic Si. Theoretical analysis indicates that,although AlB2 does not take part directly in the nucleation process in pure Al in the presence of Si, it provides a substrate for precipitation of a small content of Si from which α-Al will grow without any undercooling. When the temperature decreases to eutectic line, AlB2 subsequently nucleates eutectic Si; AlB2 particles appear in two different morphologies, namely, hexagonal platelet and tetradehedron morphology which depend on the processing temperature conditions.

  3. Effect of silicon on oxidation of Ni-15Al alloy

    Institute of Scientific and Technical Information of China (English)

    WU Ying; NIU Yan; WU Wei-tao

    2005-01-01

    The oxidation of binary Ni-Al alloy containing 15% (mole fraction, the same below if not mentioned)Al (Ni-15Al), and of a ternary alloy with the same Al content but also containing 4% Si (Ni-4Si-15Al) has been studied at 1 000 ℃ under 1.0× 105Pa O2 to examine the effect of the addition of Si on the oxidation of Ni-15Al. Oxidation of Ni-15Al produces a duplex scale composed of an outer NiO layer and an inner layer riched in Al2O3. On the contrary, Ni-4Si-15Al forms an external alumina layer directly in contact with the alloy presenting only trace of NiO and the Ni-Al spinel. As a result, the kinetics of Ni-15Al shows a fast initial stage followed by two subsequent parabolic stages with decreasing rate constants, while Ni-4Si-15Al presents essentially a single nearly-parabolic behavior with a rate constant similar to that of the final stage of Ni-15Al. Therefore, the addition of 4% Si significantly reduces the oxidation rate during the initial stage by preventing the formation of Ni-riched scales and promoting an earlier development of an exclusive external alumina layer on the alloy surface.

  4. Creep strength of centrifugally cast Al-rich TiAl alloys

    Energy Technology Data Exchange (ETDEWEB)

    Sturm, D., E-mail: daniel.sturm@masch-bau.uni-magdeburg.de [Otto-von-Guericke-Universitaet Magdeburg, Institut fuer Werkstoff- und Fuegetechnik, Lehrstuhl Werkstoffprueftechnik, Postfach 4120, D-39016 Magdeburg (Germany); Heilmaier, M.; Saage, H. [Otto-von-Guericke-Universitaet Magdeburg, Institut fuer Werkstoff- und Fuegetechnik, Lehrstuhl Werkstoffprueftechnik, Postfach 4120, D-39016 Magdeburg (Germany); Paninski, M.; Schmitz, G.J.; Drevermann, A. [ACCESS e.V., Intzestrasse 5, D-52072 Aachen (Germany); Palm, M.; Stein, F.; Engberding, N. [Max-Planck-Institut fuer Eisenforschung GmbH, Max-Planck-Str. 1, D-40237 Duesseldorf (Germany); Kelm, K.; Irsen, S. [Stiftung Caesar, Electron Microscopy, Ludwig-Erhard-Allee 2, 53175 Bonn (Germany)

    2009-06-15

    High-temperature creep of a binary Al{sub 60}Ti{sub 40} (at.%) alloy in the as-cast state and after annealing at 1223 K for 200 h which produced nearly lamellar {gamma}-TiAl + r-Al{sub 2}Ti microstructure was studied utilizing creep compression tests in a temperature range between 1173 and 1323 K in air. The material was manufactured by centrifugal casting. Microstructural characterization was carried out employing light-optical scanning (SEM) and transmission electron microscopy (TEM) as well as X-ray diffraction (XRD) analyses. It is shown that the alloy exhibits reasonable creep resistance at 1173 K, especially in relation to its low density of around 3.8 g/cm{sup 3}. Stress exponents calculated as n = {Delta}log (strain rate)/{Delta}log (stress) = 4 were found to be relatively constant for the temperature and stress regime investigated. This indicates that dislocation climb may be the rate controlling creep mechanism. The assessment of creep tests conducted at identical stress levels and varying temperatures yielded activation energies for creep of around Q = 457 kJ/mol in the as-cast condition. This value is significantly higher than those found in literature for interdiffusion of Al or Ti in {gamma}-TiAl. It is concluded that the difference is a due to the instability of the microstructure of the as-cast multi-phase alloy.

  5. Formation of Nb3Al in powder processed Nb-Al superconductors

    International Nuclear Information System (INIS)

    In high magnetic fields, the critical current density is strongly dependent on the upper critical field, which is determined primarily by the stoichiometry of the Nb3Al. The critical temperature (T/sub c/), like the upper critical field, is considered to be a measure of the ''intrinsic'' quality of the superconductor, indicating the stoichiometry, order, and strain. If the A15 phase is stoichiometric and well ordered, a high T/sub c/ (and high H/sub C2/) is expected, regardless of the volume fraction of superconductor. On the other hand, if sigma phase is present with the A15, the resultant composition gradient across the sigma-A15 interface(s) requires that some of the A15 be off-stoichiometric, and therefore that the T/sub c/ (and H/sub C2/) be low. Thus the extent of the A15 (Nb3Al) reaction and the quality of the A15 formed are interdependent. This work focuses on the factors that control the extent of Nb3Al formation in Nb/Al powder wires. The morphology and content of the reacted and unreacted wires are studied in optical, SEM, and TEM micrographs. Critical current density data and its dependence on processing are explained in terms of the unreacted microstructure and its effect on the extent of Nb3Al formation. As a method of improving the critical current density, a new variation of the conventional powder process for wire manufacturing is developed and tested

  6. Compactibility of Al/Al2O3 Isotropic Composite with Variation of Holding Time Sintering.

    Directory of Open Access Journals (Sweden)

    Eddy S Siradj

    2008-11-01

    Full Text Available The requirement of component with structural ability, light weight and also strength is increasing base on Metal Matrix Composites (MMCs by aluminum as matrix (AMCs. A structural ability is connected to composites compactibility which is depend on quality of interfacial bounding. Powder metallurgy is one of method to produce composite with powder mixing, compacting and sintering. Volume fractions reinforced and sintering time can influence composites compactibility. Volume fractions reinforced variable can produce different reinforcement effect. Beside that, on sintering enables the formation of new phase during sintering time. In this research, Al/Al2O3 isotropic composites are made with aluminum as matrix and alumina (Al2O3 as reinforced. Volume fraction reinforced used 10%. 20%. 30% and 40%. Sintering temperature and compaction pressure are each 600oC and 15 kN. The tests that applied are compression and metallographic test. The result that obtained is optimum compactibility of Al/Al2O3 composite reached at holding time 2 hour. During sintering, new phase can occur that is aluminum oxides (alumina, with unstable properties. The best volume fraction reinforced and holding time sintering are 40% and 2 hours.

  7. Properties of an AlGaN/AlN distributed-Bragg-reflector structure

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Li-Li; Liu, Zhan-Hui; Huang, Xiao-Gu; Li, Qing-Fang [Nanjing University of Information Science and Technology, Nanjing (China); Zhang, Rong; Xie, Zi-Li; Xiu, Xiang-Qian [Nanjing University, Nanjing (China)

    2014-10-15

    An AlGaN/AlN distributed-Bragg-reflector (DBR) structure with a high Al content was grown by using plasma-assisted molecular beam epitaxy (PA-MBE). The properties of the sample were characterized by using the transmission electron microscopy, high-resolution X-ray diffraction, atomic force microscopy, and reflectivity spectrum measurements. The reciprocal space mapping analysis indicated that the strain in the AlGaN layers was partially relaxed. The morphology of the DBR exhibited a surface covered by grains (average size of about 130 nm), and the surface roughness was about 2 nm. The spectral measurements showed that the DBR structure presented a peak reflectivity of 68.8% at the center wavelength of 247 nm, which indicated that this DBR structure could work in the deep solar-blind UV region with acceptable reflectivity. However, the optical properties of the DBR structure were deteriorated by the fluctuation of the Al composition, non-uniformity of the layer thickness, the blurry, rough interface in the DBR structure, and so on.

  8. Tolerancia al co en celdas de combustible

    Directory of Open Access Journals (Sweden)

    BIBIAN HOYOS

    2008-01-01

    Full Text Available El entendimiento completo del proceso de adsorción y posterior oxidación de moléculas de CO en platino es de fundamental importancia para el desarrollo de celdas de combustible poliméricas que operan a baja temperatura. En este trabajo se presenta una revisión de las cinco estrategias experimentales más importantes en la búsqueda de mejorar la tolerancia al CO: disminución del potencial de inicio de la reacción de oxidación, reducción de la cantidad de CO adsorbido, utilización de pequeñas cantidades de oxígeno en la corriente de alimentación al ánodo, aumento de la temperatura de operación y limpieza del CO a la entrada. Aunque se han desarrollado catalizadores bastante promisorios (PtMo y PdAu, todavía se sigue considerando a la mezcla Pt-Ru como el catalizador anódico más eficiente para combustibles que contienen 10 ppm de CO o más. La estrategia de inyectar oxígeno al ánodo parece promisoria pero requiere el desarrollo de nuevas membranas más resistentes y de la implementación de condiciones más seguras de operación de la celda. El diseño estructural de ánodos especiales con múltiples capas soportando catalizadores específicos para cada tipo de combustible puede ser una estrategia muy atractiva.

  9. Altern als Widerstand Aging as Resistance

    Directory of Open Access Journals (Sweden)

    Roberta Maierhofer

    2005-07-01

    Full Text Available Gullettes kulturwissenschaftliche Untersuchung Aged by Culture ist wie bereits ihre zwei vorangehenden Werke, die sich mit Altern beschäftigen – Safe at Last in the Middle Years: The Invention of the Midlife Progress Novel (1988 und Declining to Decline. Cultural Combat and the Politics of the Middle (1997 –, von großem persönlichen Engagement und durch ein politisches Anliegen motiviert. Sowohl die Dringlichkeit als auch der Widerstand, den Gullette, die sich als „age critic“ definiert, als moralische und politische Notwendigkeit postuliert, werden in der Zweiteilung der Abhandlung angesprochen: „Cultural Urgencies“ und „Theorizing Age Resistantly“. Während Gullette den Begriff „aged by culture“ bereits in Declining to Decline einführt, stellt sie ihn nun in den Mittelpunkt ihrer Untersuchung. Das Buch ist einerseits einer gesellschaftspolitischen Analyse der USA gewidmet, andererseits wird eine Theorie des Widerstands gegenüber Altersdiskriminierung entwickelt.Gullette’s cultural studies based analysis Aged by Culture is marked by great personal engagement and motivated by political goals, as are her two previous texts that deal with aging: Safe at Last in the Middle Years: The Invention of the Midlife Progress Novel (1988 and Declining to Decline. Cultural Combat and the Politics of the Middle (1997. Both the urgency as well as the resistance that Gullette, who defines herself as an “age critic,” postulates as a moral and political necessity are addressed in the two parts of the text: “Cultural Urgencies” and “Theorizing Age Resistantly.” Whereas Gullette had already introduced the concept “aged by culture” in Declining to Decline, now she has placed it at the center of her examination. On the one hand, the book is devoted to a sociopolitical analysis of the USA; on the other hand, it develops a theory of resistance to age discrimination.

  10. Micro-structural evaluation of Ti/Al/Ni/Au ohmic contacts with different Ti/Al thicknesses in AlGaN/GaN HEMTs

    Energy Technology Data Exchange (ETDEWEB)

    Mahajan, Somna S., E-mail: somnamahajan@gmail.com; Dhaul, Anuradha; Laishram, Robert; Kapoor, Sonalee; Vinayak, Seema; Sehgal, B.K.

    2014-04-01

    Highlights: • Ohmic contacts with four different Ti/Al metal thickness ratios were fabricated on undoped Al{sub .28}Ga{sub .72}N/GaN HEMT under various annealing cycles using Rapid thermal processor. • Ohmic contact with Ti/Al metal thickness ratio, 1/5 showed superior quality in terms of R{sub c} and surface morphology. • Ni–Al alloy segregation on the surface as analyzed by EDAX seems to be related to bumpy surface morphology. • Ohmic contact with Ti/Al metal ratio 1/5 showed the presence of TiN by X-ray diffraction analysis. This was further confirmed by SIMS analysis. • The lower level of elemental Ti and Al at the surface of the contact with Ti/Al metal thickness ratio 1/5 compared to the other contacts indicated lower oxidation possibility and therefore superior quality ohmic contacts with the metal ratio 1/5. - Abstract: In this work, ohmic contacts were formed by varying the Ti/Al thickness ratio in the metal stack of Ti/Al/Ni/Au on Al{sub .28}Ga{sub .72}N/GaN HEMT epistructure followed by annealing in the temperature range 740–860 °C by rapid thermal processor (RTP). The contacts were electrically characterized for contact resistance (R{sub c}) and the sheet resistance (R{sub s}) of AlGaN/GaN epistructure. The ohmic contacts formed by Ti/Al metal thickness ratio of 1/5 exhibited lowest R{sub c} values and better surface morphology compared to the contacts formed by other Ti/Al metal thickness ratios. The difference observed in the electrical characterization of these contacts was correlated with their X-ray diffraction (XRD) and secondary ion mass spectroscopy (SIMS) analyses. The surface morphology of the ohmic metal post annealing showed two distinct regions in scanning electron microscope (SEM) images. The energy dispersive X-ray analysis (EDAX) identified these regions as Ni–Al and Au–Al rich. Ni–Al rich region is believed to be responsible for rough morphology. Further, the contact formed with Ti/Al metal thickness ratio 1

  11. Umsatzerfassung als Teil des Earnings Management

    OpenAIRE

    Meyer, C.

    2008-01-01

    Mit Ruedi Volkart – er damals ausserordentlicher Professor und ich Oberassistent am Institut für schweizerisches Bankwesen – habe ich in den achtziger Jahren sehr eng zusammengearbeitet. Wir haben zusammen sehr viele Seminare an der Universität und in der Wirtschaftspraxis erteilt. Mein damaliger persönlicher Forschungsfokus galt dem Rechnungswesen der Banken. Heute, mehr als zwanzig Jahre später, interessieren mich nach wie vor Themen des Rechnungswesens. Eines davon ist die Frage der „Umsat...

  12. Der Wirkungsmechanismus von Steinkohlenflugasche als Betonzusatzstoff

    OpenAIRE

    Hüttl, Roland

    2000-01-01

    Das Ziel dieser Arbeit war es, den seit langem strittigen Wirkungsmechanismus von Flugasche eindeutig zu klären, der Hauptursache für die Umwandlung von Ca(OH)2 in CSH-Phasen ist. Es sollte eindeutig nachgewiesen werden, ob Flugasche tatsächlich chemisch (puzzolanisch) oder hauptsächlich physikalisch als Kristallisationskeim wirkt. Weiterhin sollte der (zeitliche) Ablauf der Vorgänge ermittelt werden sowie der Einfluß der reaktionsbestimmenden Parameter. Untersucht werden sollte dabei auch, w...

  13. Ibn al-Haytham and geometry

    CERN Document Server

    Rashed, Roshdi

    2013-01-01

    Theory of Conics, Geometrical Constructions and Practical Geometry: A History of Arabic Sciences and Mathematics Volume 3, provides a unique primary source on the history and philosophy of mathematics and science from the mediaeval Arab world. The present text is complemented by two preceding volumes of A History of Arabic Sciences and Mathematics, which focused on founding figures and commentators in the ninth and tenth centuries, and the historical and epistemological development of 'infinitesimal mathematics' as it became clearly articulated in the oeuvre of Ibn al-Haytham.

  14. Carl gustav jung: al profesor honorio delgado

    OpenAIRE

    Sánchez, Luis Jaime

    2012-01-01

    Esbozo ideológico de Jung: Con la muerte de Carl Gustav Jung, se deshace -en sus personajes- el trípode ejemplar que ha sostenido en lo que va corrido del siglo XX, lo más significativo del saber psicológico. Con Freud y Adler, Jung ayudo poderosamente a conformar  el a veces crudo y rudo andamiaje de una psicología singular, en el contorno y en la hondura, cuyos problemas -a pesar de todo- se debaten aún en la periferia y en la profundidad del hombre contemporáneo, al cual Jung se acerco sie...

  15. Sistemas Avanzados de Asistencia al Conductor

    OpenAIRE

    Jimenez Ruiz, Francisco; Gómez Casado, Oscar; Naranjo Hernández, José Eugenio; Serradilla García, Francisco; López, José María; Martín, Ángel

    2011-01-01

    El control inteligente de vehículos autónomos es uno de los retos actuales más importantes de los Sistemas Inteligentes de Transporte. La aplicación de técnicas de inteligencia artificial para la gestión automática de los actuadores del vehículo permite a los diferentes sistemas avanzados de asistencia al conductor (ADAS) y a los sistemas de conducción autónoma, realizar una gestión de nivel bajo de una manera muy similar a la de los conductores humanos, mejorando la seguridad y el confor...

  16. Del mito creacionista al mito futurista

    Directory of Open Access Journals (Sweden)

    Fernando Uhía

    2011-12-01

    Full Text Available La primera foto tomada a la Tierra desde el espacio, en 1946, es uno de los signos de la reprogramación mitológica que está afectando la percepción actual de las ciencias y las artes. Esta reprogramación opone a Dios como artífice y al artista como dios creador: un superhumano tecnólogo y un artista administrador de la Tierra. Se repasa en esta reprogramación el papel de las academias de arte, de las revoluciones científicas, del arte de vanguardia y del arte pop.

  17. Aproximaciones al concepto de interactividad educativa

    OpenAIRE

    Zangara, Alejandra; Sanz, Cecilia Verónica

    2012-01-01

    Este trabajo presenta una reflexión sobre el concepto de interactividad, y en particular, sobre interactividad educativa. Hoy en día se escucha hablar de software interactivo, televisión digital interactiva, interacción/interactividad, y se asume el concepto de interactividad sin una reflexión sobre éste. Se proponen aquí algunos puntos de análisis al respecto, una diferenciación entre interacción e interactividad, y una vinculación entre interactividad educativa y el concepto de distancia tr...

  18. 1950 En torno al Museo Louisiana 1970

    OpenAIRE

    García Sánchez, Carmen

    2015-01-01

    La tesis “1950 En torno al Museo Louisiana 1970” analiza varias obras relacionadas con el espacio doméstico, que se realizaron entre 1950 y 1970 en Dinamarca, un periodo de esplendor de la Arquitectura Moderna. Tras el aislamiento y restricciones del conflicto bélico que asoló Europa, los jóvenes arquitectos daneses, estaban deseosos por experimentar nuevas ideas de procedencia internacional, favorecidos por diferentes circunstancias, encuentran el mejor campo de ensayo en el espacio doméstic...

  19. Ambientes virtuales como apoyo al Aprendizaje Colaborativo

    OpenAIRE

    Leguizamón, Guillermo; Chiarani, Marcela Cristina; Lucero, María Margarita; Pianucci, Irma Guadalupe; García, Berta Elena; Ponce, Viviana; Allendes Olave, Paola A.

    2005-01-01

    A partir de las conceptualizaciones sobre Educación a Distancia (EaD); y las Tecnologías disponibles para la EAD; se analizan los Ambientes Virtuales y su relación con el Código Abierto; lo que conlleva a presentar, en forma de grilla, las pautas y alcances de evaluación de plataformas virtuales de OS factibles de ser adaptados hacia la consecución de un Ambiente Virtual como apoyo al Aprendizaje Colaborativo. Con la puesta a punto, aplicación y relevo de esta grilla se estará en condicion...

  20. Respuesta inmune innata humana al rotavirus

    OpenAIRE

    Juanita Angel; Franco, Manuel A.

    2004-01-01

    Localizadas en los órganos periféricos en un estado inmaduro, las células dendríticas (CD) sirven como centinelas del sistema inmune, esperando la entrada de los patógenos (1,2). Al encontrarse con un patógeno, la CD «madura» y migra a los órganos linfáticos secundarios donde activa a los linfocitos T. Este proceso de diferenciación de las CD ha sido reproducido in vitro. A partir de monocitos circulantes en sa...