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Sample records for al acido nalidixico

  1. Enfermedad acido-peptica

    OpenAIRE

    Echavarría, Hector Raúl; Fundación Valle de Lili; Mendoza, Alfredo

    1999-01-01

    ¿En qué consisten las enfermedades que se denominan con el término genérico de enfermedad acido-péptica?/ ¿Cuáles son sus síntomas?/ ¿Cómo se comporta la enfermedad acido-péptica y cuáles son sus causas?/ ¿Cómo se evitan estas enfermedades y como se tratan?

  2. Azione citodifferenziante ed antitumorale dell'acido ellagico

    OpenAIRE

    Vanella, Luca

    2011-01-01

    Il lavoro ha lo scopo di valutare l'effetto citodifferenziante ed antitumorale dell'acido ellagico in tre diverse linee cellulari prostatiche a diverso grado di invasivita' (DU145, LnCap, BPH1). I risultati della Cromogranina A e della P75 NGRF, ottenuti mediante immunofluorescenza, evidenziano un'azione citodifferenziante dell'acido ellagico in maniera dose dipendente. Inoltre i risultati dimostrano come l'acido ellagico abbia la capacita' di ridurre, in maniera dose dipendente, sia l'espres...

  3. Cross linkage studies with the membranes of the vesicular stomatitis virus using radioactive 4-acido and 5-acido palmitic acid

    International Nuclear Information System (INIS)

    Verfondern, M.

    1983-01-01

    In the study described here the spatial arrangement of lipids and proteins in the VS virus was investigated on the basis of the covalent cross linkage technique. The formation of such cross linkages is brought about by the action of photosensitive acidosubstituted lipids, which permit acido functions to be introduced into a membrane in a previously defined position. Subsequently, photolysis helps to trigger the generation of radioactive nitrenes that react with the proteins and lipids in their immediate vicinity in a direct and non-selective way. The findings revealed by this study have raised questions as to the possibility of lipid-protein and lipid-lipid interactions, which is also discussed. (orig./MG) [de

  4. ANALISIS DEL CO-TRATAMIENTO PASIVO DE AGUAS RESIDUALES MUNICIPALES Y DRENAJE ACIDO DE MINAS EN CERRO RICO DE POTOSÍ, BOLIVIA

    Directory of Open Access Journals (Sweden)

    William H.J. Strosnider

    2015-01-01

    Full Text Available El drenaje acido de minas (DAM es un problema a nivel mundial. El co-tratamiento pasivo de DAM con aguas residuales municipales (ARM es una manera efectiva y de bajo costo que utiliza los nutrientes de ARM para tratar las concentraciones de metales y sulfato en DAM. Cerro Rico de Potosí, Bolivia es una de las grandes ciudades mineras en el mundo que tiene muchos problemas con el DAM. El objetivo de este estudio fue determinar velocidades de reacción de Al, Fe, Mn, Zn, y otros metales en DAM provenientes de un flujo de agua en Cerro Rico usando un sistema reactor de tres etapas. El DAM tenía un pH de 3.58, acidez de 1080 mg/L equivalente a CaCO3 conteniendo concentraciones de 12, 68, 17, y 550 mg/L de Al, Fe, Mn y Zn respectivamente. Las velocidades de reacción de Al, Fe, Mn y Zn fueron de 1.43, 2.09, 0.01 y 0.10 d-1, respectivamente.

  5. Indagine su un focolaio di tossinfezione da Salmonella enterica subsp. enterica serovar Hadar nella regione Abruzzo

    Directory of Open Access Journals (Sweden)

    Primula Semprini

    2008-06-01

    Full Text Available E’ stato eseguito uno studio comparativo tra 22 ceppi di Salmonella Hadar isolati da soggetti coinvolti in un focolaio di tossinfezione alimentare in Abruzzo nel 2000 e 21 ceppi dello stesso sierotipo isolati da carni avicole e da feci umane in Abruzzo e Molise nel periodo 2000 e 2001. L’indagine aveva come obiettivo di fornire una interpretazione epidemiologica del focolaio di tossinfezione alimentare determinando il grado di similarità tra i ceppi di Salmonella Hadar isolati dai soggetti coinvolti nel focolaio, quelli isolati da carne avicola, identificata ma non confermata come possibile fonte di infezione, e da altri campioni umani pervenuti in laboratorio. A tal fine sono state impiegate tecniche di caratterizzazione genotipica come pulsed-field gel electrophoresis (PFGE e random amplified polymorphic DNA (RAPD e sono stati determinati i pattern di resistenza agli antimicrobici. Dall’analisi in PFGE dei profili di restrizione ottenuti con XbaI e BlnI sono stati identificati 12 pulsotipi suddivisi in 3 gruppi. La RAPD non ha fornito indicazioni non riuscendo a discriminare i ceppi isolati dai soggetti con gastroenterite appartenenti al focolaio tossinfettivo. Il test di resistenza agli antimicrobici ha evidenziato pattern di resistenza multipla ma non sono stati identificati ceppi resistenti al Ciprofloxacin o altri Chinoloni testati. I ceppi aviari sono risultati resistenti all’acido nalidixico mentre solo il 31,8% di quelli umani ha presentato tale profilo. Da un’analisi combinata dei pattern di resistenza e dei pulsotipi sono stati identificati 4 profili di cui quello associato al focolaio è risultato non correlato agli altri presenti nello stesso periodo. E’ stata confermata la necessità di applicare un set di metodi di analisi differenti per garantire una migliore caratterizzazione e una maggiore capacità discriminante nell’identificazione delle possibili origini della contaminazione e stabilire correlazioni fra gli

  6. Interchange reaction of disulfides and denaturation of oxytocin by copper(II)/ascorbic acid/O2 system.

    Science.gov (United States)

    Inoue, H; Hirobe, M

    1987-05-29

    The interchange reaction of disulfides was caused by the copper(II)/ascorbic acid/O2 system. The incubation of two symmetric disulfides, L-cystinyl-bis-L-phenylalanine (PP) and L-cystinyl-bis-L-tyrosine (TT), with L-ascorbic acid and CuSO4 in potassium phosphate buffer (pH 7.2, 50 mM) resulted in the formation of an asymmetric disulfide, L-cystinyl-L-phenylalanine-L-tyrosine (PT), and the final ratio of PP:PT:TT was 1:2:1. As the reaction was inhibited by catalase and DMSO only at the initial time, hydroxyl radical generated by the copper(II)/ascorbic acid/O2 system seemed to be responsible for the initiation of the reaction. Oxytocin and insulin were denatured by this system, and catalase and DMSO similarly inhibited these denaturations. As the composition of amino acids was unchanged after the reaction, hydroxyl radical was thought to cause the cleavage and/or interchange reaction of disulfides to denature the peptides.

  7. Peracetic acid as disinfectant of municipal wastewaters; L'acido peracetico nella disinfezione dei reflui urbani

    Energy Technology Data Exchange (ETDEWEB)

    Funari, E. [Istituto Superiore di Sanita' , Laboratorio di Igiene Ambientale, Reparto di Medicina Ambientale, Rome (Italy); Lopez, A. [Consiglio Nazionale delle Ricerche, Istituto di Ricerca sulle Acque, Reparto di Chimica e Tecnologia delle Acque, Bari (Italy)

    2000-09-01

    altri settori tra cui quello alimentare, e' dovuto, diversamente da quanto si verifica con l'uso di altri disinfettanti, alla dichiarata assenza di sottoprodotti pericolosi ed al conseguente mancato aumento di tossicita' dei reflui trattati. Tuttavia, nonostante tali premesse, nel settore dei reflui urbani l'impiego dell'acido peracetico stenta ad affermarsi sia per fattori economici che per la prevedibile diffidenza verso un prodotto relativamente nuovo che cosi' <> la limitata conoscenza, specie se comparata con quella relativa al cloro, della sua reale efficacia germicida nei confronti dei diversi tipi di microrganismi patogeni (batteri, virus, parassiti), delle sue proprieta' eco-tossicologiche, delle sue prestazioni come disinfettante in impianti in piena scala. Il presente lavoro oltre a fornire un'ampia raccolta di riferimenti bibliografici, esamina i dati disponibili sul PAA con particolare riferimento: all'efficacia disinfettante nei confronti dei diversi microrganismi patogeni; alla formazione e tossicita' di sottoprodotti di disinfezione; all'impatto ambientale associato allo scarico di reflui trattati con PAA nei corpi idrici; alle condizioni operative adottate in impianti di dimensioni signficative.

  8. Acido-basic control of the thermoelectric properties of poly(3,4-ethylenedioxythiophene)tosylate (PEDOT-Tos) thin films

    DEFF Research Database (Denmark)

    Khan, Zia Ullah; Bubnova, Olga; Jafari, Mohammad Javad

    2015-01-01

    study the variation in the thermoelectric properties by a simple acido-basic treatment. The emphasis of this study is to elucidate the chemical changes induced by acid (HCl) or base (NaOH) treatment in PEDOT-Tos thin films using various spectroscopic and structural techniques. We could identify changes...... in the nanoscale morphology due to anion exchange between tosylate and Cl- or OH-. But, we identified that changing the pH leads to a tuning of the oxidation level of the polymer, which can explain the changes in thermoelectric properties. Hence, a simple acid-base treatment allows finding the optimum...

  9. Activity and stability of a <AlGaPON>> oxynitride in the dehydrogenation of isobutane

    Energy Technology Data Exchange (ETDEWEB)

    Delsarte, S.; Grange, P. [Univ. Catholique de Louvain (Belgium). Unite de Catalyse et Chimie des Materiaux Divises; Laurent, Y. [Lab. de Chimie des Materiaux, Univ. de Rennes 1, Rennes (France)

    2000-07-01

    Isobutane dehydrogenation was studied on platinum impregnated mixed aluminium gallium phosphorus oxide and oxynitride, in a continuous, flow micro-reactor at 500-550 C. Comparison of the <AlGaPO>> and <AlGaPON>> shows the importance of nitridation on the acido-basic properties of the catalyst. A deactivation of the catalyst, due to the deposition of carbonaceous species on the surface, was observed. As the properties of the oxynitride would be altered by a regeneration treatment at high temperature with flowing oxygen, the possibility of decreasing the deactivation rate by decreasing the reaction temperature and by adding hydrogen to the reactant mixture was explored. Catalytic tests, carried out at different hydrogen partial pressures, showed that the hydrogen inhibits the carbon deposition on the surface of the catalyst and thus increases the catalytic stability. (orig.)

  10. Modificación estructural de Poli(Acido Láctico) (PLA) mediante extrusión reactiva: estudio preliminar en mezclador interno escala laboratorio

    OpenAIRE

    Espejo, Lucas

    2011-01-01

    Doble titulació Este proyecto, realizado en Centro Catalá del Plástico y por lo tanto implicado en el dominio de los polímeros, pretende preparar y caracterizar sistemas de Acido Poli(Láctico) (PLA) con extensores de cadena (CE) que serían adecuados y eficientes para el sector de los envases. Los procesos tal la Inyección y/o Extrusión empleando el PLA en este campo se enfrentan a la pérdida de las propiedades termo-mecánicas. Es el resultado de la degradación térmica y h...

  11. FOOD SAFETY AND QUALITY IN DEVELOPING COUNTRIES: THE ROLE OF LACTIC ACID BACTERIA

    OpenAIRE

    ANGRI, MATTEO

    2016-01-01

    La sicurezza e la qualità degli alimenti sono tutt’ora un problema critico per i paesi in via di sviluppo. Le diete a basso contenuto di acido folico, per esempio, possono causare gravi problemi di salute, soprattutto nei bambini. Gravi disturbi legati al tubo neurale (DTN) nei neonati possono derivare infatti da madri che hanno insufficiente apporto di acido folico (400-600 g / giorno) durante il periodo di gravidanza. Inoltre, se non adeguatamente protetti o trattati, I prodotti alimentari ...

  12. Study of chemical and electrochemical properties of some elements in molten NaAlCl

    International Nuclear Information System (INIS)

    Bermond, Alain

    1976-01-01

    We describe a study of the electrochemical and chemical properties in molten mixtures of Aluminium Chloride-Sodium chloride, at 210 deg. C and the concept of acidity, related to chloride activity, is previously summarized. In a first part, the study of Mercury and Cadmium by means of electro-analytical techniques, states the Hg 2+ 2 , Hg 2+ , Cd 2+ 2 and Cd 2+ ions and their acid properties. Some diagrams Equilibrium potential vs acidity are the synthesis of these results. In a second part, it is shown that a nickel electrode is an indicator of the presence of oxide ions; from interpretation of electrochemical results, O 2 appears to behave, in terms of the chloro-acido-basicity concept, as a strong di-base, giving the solvated form AlOCl - 2 , or a strong tri-base giving AlOCl. A saturation effect by Al 2 O 3 appears when the oxide concentration is increased; the solubility of Al 2 O 3 versus acidity is determined from the electrochemical results. In a third part, results for the Ni/Ni(II) or HCl/H 2 O systems are related to dissolved oxide ion presence in chloroaluminate melts; elimination of oxide ions, through H 2 O formation, by reaction with HCl is noteworthy. (author) [fr

  13. EFECTO NEFROPROTECTOR DEL ÁCIDO ASCÓRBICO EN UN MODELO DE DAÑO RENAL INDUCIDO POR GENTAMICINA EN CONEJOS

    Directory of Open Access Journals (Sweden)

    Javier Antonio Padilla Funes

    2013-08-01

    Full Text Available Objetivo. Uno de los efectos secundarios mas notables de la Gentamicina es su nefrotoxicidad. En este estudio se propone el posible efecto nefroprotector del acido ascorbico como barredor de radicales libres de oxigeno. Metodología. Se ejecuto un estudio experimental en 24 conejos machos, raza Nueva Zelanda, cuyo peso fue de 1,5 +/- 0,5 Kg. Los sujetos experimentales fueron distribuidos en tres grupos. El grupo Control se manejo con Gentamicina a dosis de 80 mg/Kg/dia por via IM. El grupo Acido Ascorbico se trato a dosis de 200 mg/kg/dia via IP y Gentamicina 80mg/Kg/dia IM. El grupo Sham se manejo con SSN 0,9% por via IP e IM, durante cinco dias consecutivos, para cada grupo. Se determinaron los siguientes parametros: creatinina serica, N-Acetil s-D glucosaminidasa urinaria (NAG-U, diuresis e histopatologia de las muestras renales. Resultados. La creatinina serica fue significativamente mayor para el grupo Control respecto al grupo Acido Ascorbico (p<0,05. Respecto a la diuresis, se observo una tendencia a la poliuria en el grupo Control. En cuanto a NAG-U, se observo inhibicion completa de la actividad enzimatica en el grupo Acido Ascorbico. El analisis histopatologico demuestra hallazgos de necrosis tubular aguda en el 100% del grupo control, mientras que en el grupo Acido Ascorbico se obtuvo en un 50% de los sujetos unicamente detritos intraluminales. Conclusiones. La administracion concomitante de Acido Ascorbico con Gentamicina, disminuye significativamente el dano tubular renal, evidenciado en los valores de creatinina serica, NAG, diuresis e histopatologia renal.

  14. Stability of RNA and DNA in Bone Marrow Cells, Demonstrated with Tritiated Cytidine and Thymidine; Emploi de la Cytidine et de la Thymidine Tritiees pour Demontrer la Stabilite de l'ARN et l'ADN dans les Cellules de la Moelle Osseuse; 0421 0442 0430 0414 ; Estudio de la Estabilidad de los Acidos Ribonucleico y Desoxirribonucleico de las Celulas de la Medula Osea, Utilizando Citidina y Timidina Tritiadas

    Energy Technology Data Exchange (ETDEWEB)

    Bond, V. P.; Feinendegen, L. E.; Cronkite, E. P. [Medical Research Centre, Brookhaven National Laboratory, Upton, Long Island, NY (United States)

    1962-02-15

    maniere que l'ADN. L'ARN et l'ADN de formation recente ne se diluent dans les cellules qu'a la faveur de la division cellulaire. (author) [Spanish] Los autores han estudiado el metabolismo de los acidos desoxirribonucleico y ribonucleico utilizando timidina tritiada (timidina-{sup 3}H), un precursor especifico del acido desoxirribonucleico, y citidina tritiada (citidina-{sup 3}H), un precursor comun de los acidos ribonucleico y desoxirribonucleico. Empleando citidina-{sup 3}H se determino autorradiograficamente la incorporacion diferencial por celula en los acidos ribonucleico y desoxirribonucleico, asi como en el espacio soluble. La misma determinacion se efectuo empleando metodos autorradiograficos y quimicos en el caso de poblaciones celulares, mediante extraccion diferencial aplicando un tratamiento apropiado con acido perclorico. Los estudios preliminares sobre renovacion realizados en celulas de HeLa con citidina-{sup 3}H pusieron de manifiesto la funcion precursora del acido ribonucleico nuclear respecto del acido ribonucleico citoplasmatico. La conservacion y distribucion del indicador en la fraccion acido ribonucleico es compatible con una mayor estabilidad de las macromoleculas de dicho acido. Asimismo, la incorporacion continua del indicador en la fraccion acido desoxirribonucleico es compatible con la presencia de un precursor de dicho acido en las ultimas fases de la sintesis. Fenomenos analogos se observaron en las celulas no maduras de la medula osea de la tata, estudiadas durante los dias consecutivos a la administracion de citidina-{sup 3}H por via intravenosa. La actividad del tritio en la fraccion soluble en acido y en las fracciones ARN y ADN se evaluo por metodos quimicos y autorradiograficos. Se comprobo que las tres curvas son paralelas desde el dia que sigue al de inyeccion y paralelas asimismo a las curvas de actividad del tritio en el acido desoxirribonucleico, cuando este se marca con timidina- {sup 3}H. La velocidad de disminucion de la

  15. Proposal to neutralize acid fluids from wells in the Los Humeros, Pue., geothermal field; Propuesta para la neutralizacion de fluidos acidos provenientes de pozos del campo geotermico de Los Humeros, Pue.

    Energy Technology Data Exchange (ETDEWEB)

    Flores Armenta, Magaly del Carmen; Ramirez Montes, Miguel; Garcia Cuevas, Juan Manuel [Comision Federal de Electricidad, Gerencia de Proyectos Geotermoelectricos, Morelia, Michoacan (Mexico)]. E-mail: magaly.flores@cfe.gob.mx

    2009-07-15

    Neutralizing an acidic fluid consists of adding a sodium hydroxide solution to neutralize the H group of acids, therefore increasing the pH. The injection of sodium hydroxide has to be continuous and at a proper depth inside the well to protect against the corrosion of casing and surface equipment. Neutralization is a common practice used in geothermal fields, such as at The Geysers in the US and Miravalles in Costa Rica-places where aggressive fluids cause problems for extracting and using geothermal fluids commercially. A zone surrounding wells H-4, H-16 and H-29 in the northern section of the Los Humeros, Pue., geothermal field, known as the Colapso Central, has shown evidence of aggressively acidic fluids. Several wells drilled in the area had to be repaired, thus plugging and isolating the deepest production zones. Well H-43 was drilled two years ago in the northern zone of the field, and even though it is not located in the aggressive-fluid zone, the well presents mineralogical features possibly indicating the presence of acidic fluids. Therefore, before producing this well it has been proposed we install a neutralization system with general characteristics presented in this paper. The system will prevent corrosion that up to now has prevented exploitation of the deep portion of Colapso Central, helping to develop the field in a more profitable way. [Spanish] Neutralizar un fluido acido consiste en agregarle una solucion de hidroxido de sodio. Esto neutraliza el grupo de acidos H y en consecuencia aumenta el pH. La inyeccion de hidroxido de sodio se realiza de manera continua y a una profundidad adecuada dentro del pozo para proteger a la tuberia y a todo el equipo superficial contra la corrosion. La neutralizacion es una practica comun que se viene realizando en campos como Los Geysers en Estados Unidos y en Miravalles, Costa Rica, donde la presencia de fluidos agresivos causa problemas en la extraccion y aprovechamiento del fluido geotermico con fines

  16. Mechanical behaviour of AlSiC nano composites produced by ball milling and spark plasma sintering =

    Science.gov (United States)

    Buchheim, Claudia Sofia de Andrade Redondo Murilhas

    Neste trabalho foram produzidos nanocompositos de AlSiC misturando aluminio puro com nano particulas de SiC com diâmetro de 45 - 55 nm, usando, de forma sequencial, a tecnica da metalurgia do po e a compactacao por "Spark Plasma Sintering". O composito obtido apresentava graos com 100 nm de diâmetro, encontrandose as particulas de SiC localizadas, principalmente, nas fronteiras de grao. O nanocomposito sob a forma de provetes cilindricos foi submetido a testes de compressao uniaxial e a testes de nanoindentacao para analisar a influencia das nanoparticulas de SiC, da fracao volumica de acido estearico e do tempo de moagem, nas propriedades mecânicas do material. Para efeitos de comparacao, utilizouse o comportamento mecânico do Al puro processado em condicoes similares e da liga de aluminio AA1050O. A tensao limite de elasticidade do nanocomposito com 1% Vol./Vol. de SiC e dez vezes superior a do AA1050. O refinamento de grao a escala nano constitui o principal mecanismo de aumento de resistencia mecânica. Na realidade, o Al nanocristalino sem reforco de particulas de SiC, apresenta uma tensao limite de elasticidade sete vezes superior a da liga AA1050O. A adicao de 0,5 % Vol./Vol. e de 1 % Vol./Vol. de SiC conduzem, respetivamente, ao aumento da tensao limite de elasticidade em 47 % e 50%. O aumento do tempo de moagem e a adicao de acido estearico ao po durante a moagem conduzem apenas a um pequeno aumento da tensao de escoamento. A dureza do material medida atraves de testes de nanoindentacao confirmaram os dados anteriores. A estabilidade das microestruturas do aluminio puro e do nanocomposito AlSiC, foi testada atraves de recozimento de restauracao realizado as temperaturas de 150 °C e 250 °C durante 2 horas. Aparentemente, o tratamento termico nao influenciou as propriedades mecânicas dos materiais, excepto do nanocomposito com 1 % Vol./Vol. de SiC restaurado a temperatura de 250 °C, para o qual se observou uma reducao da tensao limite de elasticidade

  17. Results of test of acid fluids neutralization in the well H-43, Los Humeros geothermal field, Puebla; Resultados de la prueba de neutralizacion de fluidos acidos en el pozo H-43, campo geotermico de Los Humeros, Puebla

    Energy Technology Data Exchange (ETDEWEB)

    Flores Armenta, Magaly del Carmen; Ramirez Montes, Miguel; Sandoval Medina, Fernando; Rosales Lopez, Cesar [Comision Federal de Electricidad, Gerencia de Proyectos Geotermoelectricos, Morelia, Michoacan (Mexico)]. E-mail: magaly.flores@cfe.gob.mx

    2011-07-15

    The well H-43 was drilled in Los Humeros Geothermal Field, Pue., in 2007 and 2008. When well production was measured, it was found the well produced acid fluids with high corrosion potential. Then it was decided to try to neutralize the acidity of the H-43 fluids by adding a solution of sodium hydroxide. This is a basic substance used to neutralize mainly the acid groups H+, and the goal was to raise the pH of the fluids to minimize its corrosive features. First sodium hydroxide was injected into the well to protect the casing of 244.4 mm (9 5/8 in) against corrosion and then all the surface installations. It was possible to increase the pH of the well fluid from 5.2 up to 6.8 without altering the steam production, thus demonstrating the neutralization procedure is feasible. The approximate costs of the neutralization tests performed, including equipment for the proposed neutralization system, the neutralizer (NaOH), and drilling the well are about 71.4 million pesos (around 5.5 million USD). We estimate a benefit/cost ratio of 1.5 and a return on investment in five years, considering the income from energy sales at present value. [Spanish] El pozo H-43 fue perforado en el campo de Los Humeros, Pue., en 2007-2008, y al evaluar su produccion se encontro que producia fluidos acidos de alto potencial corrosivo. Se decidio por tanto realizar una prueba para neutralizar la acidez de los fluidos de este pozo, que consistio en agregarle una solucion de hidroxido de sodio. Esta es una sustancia basica que neutraliza principalmente los grupos acidos H+, con lo que se buscaba aumentar el pH del fluido lo necesario para reducir al maximo su caracter corrosivo. La inyeccion del hidroxido de sodio se realizo dentro del pozo a fin de proteger de la corrosion a la tuberia de revestimiento de 244.4 mm (9 5/8 pulgadas), y posteriormente a todos los equipos superficiales. Como resultado de la prueba, se logro aumentar el pH del fluido producido por el pozo de 5.2 a un maximo de 6

  18. ESTUDIO DE LA ADSORCIÓN DE PROTEÍNAS SOBRE SUPERFICIES DE ACIDO POLILÁCTICO MEDIANTE TÉCNICAS GRAVIMÉTRICAS Y ELECTROQUÍMICAS

    Directory of Open Access Journals (Sweden)

    HUGO ARMANDO ESTUPIÑAN DURAN

    2011-01-01

    Full Text Available Metodos electroquimicos fueron utilizados para promover y evaluar la adsorcion orientada de albumina y colageno sobre superficies polimericas de acido polilactico (PLA mediante la aplicacion de un sobrepotencial anodico en un rango de 0 V a 0,45 V. La adsorcion fueestudiada usando mediciones simultaneas de espectroscopia de impedancia electroquimica (EIE y microbalanza de cristal de cuarzo (QCM, en un rango de temperaturas de 25°C a 45°C, con variaciones en proteina entre 5 y 20 ¿Êg/ml en solucion buffer de fosfato de pH 7,4. Con el aumento de la concentracion de proteinas en el electrolito, disminuye la resistencia a la transferencia de carga, exhibiendo asi una mayor adsorcion sobre la superficie, ademas de aumentar la magnitud de los cambios de masa. Se mejoro la hidrofilicidad del recubrimiento, mostrando una mayor afinidad con las soluciones de colageno y por lo tanto un aumento en la biocompatibilidad debido a la activacion superficial.

  19. Catalytic mechanism of the dehydrogenation of ethylbenzene over Fe–Co/Mg(Al)O derived from hydrotalcites

    KAUST Repository

    Tope, Balkrishna B.; Balasamy, Rabindran J.; Khurshid, Alam; Atanda, Luqman A.; Yahiro, Hidenori; Shishido, Tetsuya; Takehira, Katsuomi; Al-Khattaf, Sulaiman S.

    2011-01-01

    -H+ abstraction from ethyl group on Mg2+-O2- basic sites, followed by C-O-Mg bond formation. The α-H+ abstraction by O2-(-Mg 2+) was likely followed by β-H abstraction, leading to the formations of styrene and H2. Such catalytic mechanism by the Fe 3+ acid-O2-(-Mg

  20. Determinación espectrofluorimétrica de fitohormonas derivadas del indol y del naftaleno

    OpenAIRE

    Blanc García, María del Rosario

    2014-01-01

    Se realiza el estudio de las propiedades fluorescentes y la puesta a punto de metodología espectrofluorimétrica en disolución y en fase sólida para la determinación en aguas, suelos y formulaciones comerciales de las fitohormonas derivadas del indol: acido indol-3-acetico. acido indol-3-butirico, acido indol-3-propinoico y acido 5-hidroxiindol-3-acetico; y del naftaleno: acido 1-naftilacetico y 1-naftilacetamida. se lleva a cabo la determinación individual de cada una de las fitohormonas as...

  1. Catalytic mechanism of the dehydrogenation of ethylbenzene over Fe–Co/Mg(Al)O derived from hydrotalcites

    KAUST Repository

    Tope, Balkrishna B.

    2011-11-01

    Catalytic mechanism of ethylbenzene dehydrogenation over Fe-Co/Mg(Al)O derived from hydrotalcites has been studied based on the XAFS and XPS catalyst characterization and the FTIR measurements of adsorbed species. Fe-Co/Mg(Al)O showed synergy, whereas Fe-Ni/Mg(Al)O showed no synergy, in the dehydrogenation of ethylbenzene. Ni species were stably incorporated as Ni2+ in the regular sites in periclase and spinel structure in the Fe-Ni/Mg(Al)O. Contrarily, Co species exists as a mixture of Co3+/Co2+ in the Fe-Co/Mg(Al)O and was partially isolated from the regular sites in the structures with increasing the Co content. Co addition enhanced Lewis acidity of Fe3+ active sites by forming Fe3+-O-Co 3+/2+(1/1) bond, resulting in an increase in the activity. FTIR of ethylbenzene adsorbed on the Fe-Co/Mg(Al)O clearly showed formations of C-O bond and π-adsorbed aromatic ring. This suggests that ethylbenzene was strongly adsorbed on the Fe3+ acid sites via π-bonding and the dehydrogenation was initiated by α-H+ abstraction from ethyl group on Mg2+-O2- basic sites, followed by C-O-Mg bond formation. The α-H+ abstraction by O2-(-Mg 2+) was likely followed by β-H abstraction, leading to the formations of styrene and H2. Such catalytic mechanism by the Fe 3+ acid-O2-(-Mg2+) base couple and the Fe 3+/Fe2+ reduction-oxidation cycle was further assisted by Co3+/Co2+, leading to a good catalytic activity for the dehydrogenation of ethylbenzene. © 2011 Elsevier B.V. All rights reserved.

  2. Synthesis and characterization of PdAg as a catalyst for oxygen reduction reaction in acid medium; Sintesis y caracterizacion de PdAg como catalizador para la reaccion de reduccion de oxigeno en medio acido

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Casillas, D. C.; Vazquez-Huerta, G.; Solorza-Feria, O. [Centro de Investigacion y de Estudios Avanzados del IPN, Mexico D.F. (Mexico)]. E-mail: dcmartinez@cinvestav.mx

    2009-09-15

    This work presents the synthesis of the binary compound PdAg and the electrochemical characterization for oxygen reduction reaction (ORR) in acid medium. The catalyst is obtained from the reduction of Pd(NO{sub 3}){sub 2}·2H{sub 2}O and AgNO{sub 3} with NaBH{sub 4} in THF. The synthesized compound was physically characterized with transmission electron microscopy (TEM), sweep electron microscopy (SEM) and x-ray diffraction (XRD) of powder. Electrochemical studies were conducted to determine the catalytic activity and intrinsic properties of the PdAg material for the ORR in acid medium using cyclic voltamperometry (CV), rotary disc electrode (RDE) and electrochemical impedance spectroscopy (EIS) in a solution of H{sub 2}SO{sub 4} 0.5 M at 25 degrees Celsius. The electrochemical current-potential responses were compared to those of palladium and platinum. The kinetic results showed an increase in the performance of the bimetallic electrocatalyst containing Ag as compared to pure Pd, but less than that obtained with nanometric Pt. The Tafel slopes obtained are roughly120 mV dec-1, similar to that reported for Pt and Pd and for other Ru-based electrocatalysts. [Spanish] En este trabajo se presentan la sintesis del compuesto binario PdAg y su caracterizacion electroquimica para la reaccion de reduccion de oxigeno (RRO) en medio acido. El catalizador se obtuvo a partir de la reduccion de Pd(NO{sub 3}){sub 2}·2H{sub 2}O y AgNO{sub 3} con NaBH{sub 4} en THF. El compuesto sintetizado se caracterizo fisicamente por microscopia electronica de transmision (MET), microscopia electronica de barrido (MEB) y difraccion de rayos X (DRX) de polvos. Se realizaron estudios electroquimicos para determinar la actividad catalitica y las propiedades intrinsecas del material de PdAg para la reaccion de reduccion de oxigeno (RRO) en medio acido, utilizando las tecnicas de voltamperometria ciclica (VC), electrodo disco rotatorio (EDR) y espectroscopia de impedancia electroquimica (EIE), en

  3. The Use of Tritium-Labelled Thymidine in Studies on the Synthesis of Deoxyribonucleic Acids; Emploi de la Thymidine Tritiee Dans L'etude de la Synthese de l'Acide Desoxyribonucleique; 0418 0441 043f 043e 0414 ; Empleo de Timidina Tritiada para Estudiar la Sintesis de los Acidos Desoxirtibonucleicos

    Energy Technology Data Exchange (ETDEWEB)

    Bianchi, P. A.; Crathorn, A. R.; Shooter, K. V. [Chester Beatty Research Institute, Institute of Cancer Research, London (United Kingdom)

    1962-02-15

    balayage continu. Les deux methodes de mesure ont donne des resultats sensiblement differents. Pour chaque cellule, l'activite due au tritium, calculee d'apres les autoradiographies, a toujours paru superieure a celle de l'ADN isole. En mesurant ensuite a l'aide du compteur a balayage continu l'activite de cellules entieres, apres lavage et homogeneisation, on a obtenu des chiffres qui concordaient avec les resultats de l'autoradiographie. Il semble donc, en l'occurrence, que l'autoradiographie ne permette pas de mesurer de maniere satisfaisante la synthese de l'ADN. On a etudie l'activite associee, autre que celle de l'ADN, et entrepris sur d'autres types de cellules des etudes analogues de l'activite totale due au tritium et de l'activite de l'ADN isole; des effets similaires ont ete observes. A partir de ces donnees, on a pu distinguer plusieurs phases dans le processus de synthese : 1 Degree-Sign incorporation initiale de la thymidine a la cellule; 2 Degree-Sign phosphorylation en deux etapes au moins; 3 Degree-Sign formation d'ADN par polymerisation de la thymidine phosphorylee. Ainsi, on simplifierait a l'exces en supposant que l'incorporation de thymidine a la cellule permette de mesurer la synthese de l'ADN; il semble cependant qu'en utilisant cet indicateur on puisse obtenir des indications utiles sur les etapes preliminaires du processus. (author) [Spanish] En el curso de estudios sobre la biosintesis del acido desoxirribonucleico se han realizado algunos experimentos, utilizando celulas asciticas de Ehrlich, para investigar la fijacion e incorporacion de timidina-{sup 3}H. Despues de incubar in vitro las celulas marcadas con este compuesto, se han tomado autorradiografias de las mismas; tambien se ha aislado el acido desoxirribonucleico y se ha medido la actividad del {sup 3}H utilizando un contador de flujo. Al comparar los dos metodos de medicion, se advierte una marcada discrepancia; la actividad del {sup 3}H por celula, calculada a base de las

  4. Phosphategypsum wastes in Venice lagoon. Radiological impact; Le discariche di fosfogessi nella laguna di Venezia. Valutazioni preliminari dell'impatto radiologico

    Energy Technology Data Exchange (ETDEWEB)

    Belli, M; Blasi, M; Guogang, J.; Rosamilia, S.; Sansone, U. [Agenzia Nazionale per la Protezione dell' Ambiente, Rome (Italy); Biancotto, R.; Bidoli, P.; Sepulcri, D. [Agenzia Regionale di Prevenzione e Protezione del Veneto, Venice (Italy). Dipt. provinciale di Venezia; Cavolo, F. [Smilax, Mira, VE (Italy)

    2000-07-01

    The phosphoric minerals utilized in phosphoric acid production, presents high concentrations of radioactive materials: U238, Th 232, K 40. The phosphogypsum is the waste material obtained in the phosphoric acid production in wet process. This type of production method is employed for many years in Venice lagoon (Porto Marghera chemical plants). In this paper are reported evaluations of radiological impact on aquatic environment of lagoon. [Italian] Con il termine di fosfogessi si intende comunemente il materiale di risulta che si ottiene nella produzione di acido fosforico attraverso la via umida (attacco acido). Questa tipologia di produzione che ha operato per diversi decenni a Porto Marghera, e' finalizzata allo scopo di ottenere acido fosforico principalmente per l'industria dei fertilizzanti e quindi come prodotto intermedio per la chimica e per le preparazioni alimentari. Il fosforo, elemento principale della reazione, era ricavato da rocce fosfatiche di origine sedimentaria marina provenienti per lo piu' dall'Africa settentrionale. Il sistema produttivo utilizzato negli impianti di Porto Marghera era basato su una reazione principale, che partendo dal minerale attraverso un attacco acido, produceva acido fosforico: Ca{sub 3}(PO{sub 4}){sub 2} (Minerale Fosforico) + 3H{sub 2}SO{sub 4} (Acido Solforico) + 3H{sub 2}O (Acqua) {yields} 2H{sub 3}PO{sub 4} (Acido fosforico) + 3CaSO{sub 4}H{sub 2}O (Solfato di calcio (gesso)). In particolare il minerale era preventivamente macinato e vagliato, quindi si procedeva alla sua miscelazione con l'acido fosforico ed alla successiva reazione del composto ottenuto.

  5. Utilisation of chlorine-dioxide and peracetic acid as disinfectants of effluents from Bologna waste water treatment plant; Sperimentazione di tecniche di disinfezione mediante biossido di cloro e acido peracetico applicate alle acque reflue dell'impianto di trattamento della citta' di Bologna

    Energy Technology Data Exchange (ETDEWEB)

    Mancini, M.L. [Bologna Univ., Bologna (Italy). Dipt. di Ingegneria delle Strutture, dei Trasporti, delle Acque, del Rilevamento e del Territorio; Sorrentino, M.

    2000-01-01

    The necessity to optimize the disinfection phase in the treatment plant of waste water of Bologna made possible an experimental survey about the efficacy of two disinfectant agents utilized: chlorine-dioxide and peracetic acid. Object of the survey is to verify the possibility of utilize, full scale, also peracetic acid as disinfection agent. The experimentation regarded the reals flows adduced and discharged from the plant and it may be an useful reference to verify performance of post-treatment constructed wetlands. Particularly it has been possible to assay the efficacy of the different treatment in waste water with residual concentrations of suspended solids. [Italian] La necessita' di ottimizzare la fase di disinfezione nell'impianto di trattamento acque reflue della citta' di Bologna, sia per il miglioramento delle rese di inattivazione, sia per la riduzione dei costi di esercizio, ha reso necessaria un'indagine sperimentale sull'efficacia di due agenti disinfettanti utilizzati: il biossido di cloro e l'acido peracetico. Scopo dell'indagine e' quello di verificare la possibilita' di impiegare, a scala reale, per il refluo tipico dell'impianto di Bologna, anche l'acido peracetico quale agente di disinfezione. La sperimentazione, condotta ha interessato le portate reali addotte e scaricate dall'impianto e puo' costituire un riferimento utile verificare la fattibilita' igienico-sanitaria di post-trattamenti di lagunaggio o fertirrigazione. In particolare si e' potuta saggiare l'efficacia dei diversi sistemi di trattamento sui reflui aventi concentrazioni residue non trascurabili di solidi sospesi.

  6. Microbiota de jamones de cerdo cocidos asociada al deterioro por abombamiento del empaque

    Directory of Open Access Journals (Sweden)

    Juliana Ossa

    2010-08-01

    Full Text Available Objetivo. Caracterizar la diversidad microbiana y calidad microbiológica e higiénico sanitaria de diferentes marcas de jamones de cerdo cocidos abombados y no abombados comprados en varios supermercados de Bogotá D.C. Materiales y métodos. Se analizaron 10 marcas diferentes de jamones de cerdo cocidos comprados en tres supermercados, refrigerados bajos las mismas condiciones del consumidor, durante 45 días. Se realizó los recuentos en placa de microorganismos de interés en la industria de alimentos y de inocuidad en las muestras con o sin distensión del empaque e identificación por pruebas bioquímicas y PCR para determinar la diversidad de la microbiota. Se aislaron cepas productoras de biopelículas provenientes de la superficie de una planta de alimentos de una de las marcas de los jamones investigadas. Resultados. Se identificaron un total de 139 cepas aisladas del producto terminado, de las cuales un 99% (137 cepas pertenecen al grupo de Bacterias Acido Lácticas (BAL, el 1% restante son levaduras. De las 31 cepas aisladas de las superficies en la zona de tajado, el 97% (30 cepas presentaron formación de biopelículas. Se determinó ausencia de patógenos tanto en el producto terminado como en las muestras de las superficies.Conclusiones. El deterioro causado por abombamiento del empaque fue asociado a la presencia de BAL, debido a que fueron encontradas en la zona de tajado y en el producto terminado, de este último únicamente se aislaron BAL, en mayor proporción cepas correspondientes al género de Lactobacillus sp.

  7. Hydrogen sulfide corrosion of weld regions in API X52 steel; Corrosion por acido sulfhidrico de las regiones de soldadura en acero API X52

    Energy Technology Data Exchange (ETDEWEB)

    Arenas-Martinez, L.F [Universidad Autonoma de Coahuila, Coahuila (Mexico)]. E-mail: fernando.arenas@uadec.edu.mx; Garcia-Cerecero, G. [Corporacion Mexicana de Investigacion en Materiales S.A. de C.V., Saltillo, Coahuila (Mexico)

    2012-10-15

    The corrosion behavior of gas metal arc welding (GMAW) regions has been studied using potentiodynamic polarization and polarization resistance (LPR) techniques. Experiments were conducted in hydrogen sulfide (H{sub 2}S)-containing brine and in H{sub 2}S-free brine. Welds were made on API 5L X52 steel. Due to differences in their microstructure, chemical composition and residual stress level, weld regions exhibited different responses under H{sub 2}S corrosion. Base metal exhibited the highest corrosion rate (CR) and the most cathodic corrosion potential. [Spanish] Se estudio el comportamiento ante la corrosion de las regiones de soldadura de un cordon realizado por arco metalico con gas (GMAW) sobre un acero grado API X52 mediante las tecnicas de polarizacion potencio dinamica y resistencia a la polarizacion (LPR). Los experimentos se realizaron utilizando salmuera con 300 ppm de acido sulfhidrico (H{sub 2}S) y salmuera libre de H{sub 2}S como electrolitos. Debido a las diferencias en su microestructura, composicion quimica y el nivel de esfuerzos residuales, las regiones de soldadura mostraron diferentes respuestas a la corrosion por H{sub 2}S. El metal base exhibio la velocidad de corrosion (VC) mas alta y el potencial de corrosion mas catodico.

  8. La infección del tracto urinario (ITU en un hospital universitario de Santafé de Bogotá: etiología y evaluación de los antimicrobianos

    Directory of Open Access Journals (Sweden)

    S. Máttar

    1994-09-01

    Full Text Available Los objetivos de este trabajo fueron determinar la etiología y la sensibilidad antimicrobiana en la infección del tracto urinario (ITU. Para ello, se analizaron prospectivamente 245 orinas extra e intrahospitalarias del Hospital Universitario San Ignacio de Santafé de Bogotá. Las orinas se estudiaron a través del sedimento, Gram, tira reactiva y cultivo bacteriológico; la susceptibilidad antimicrobiana se realizó por el método de Kirby Bauer. De las 245 orinas se descartaron 45; las 200 orinas restantes fueron cultivadas, resultando 100 positivas y 100 negativas. El agente más frecuentemente aislado fue E. coli (85%, seguido de Proteus sp. (6%. Los microorganismos aislados presentaron una alta sensibilidad a la cefotaxima (100%, norflocacina (98%, netilmicina (98%, amikacina (98%, nitrofurantoína (92%, gentamicina (86%, ácido nalidixico (78% y una sensibilidad del 57% frente al trimetoprim-sulfametoxasol y el 25% a la ampicilina. Los antimicrobianos eficaces para el tratamiento de la ITU, por su bajo costo y alta actividad sobre los microorganismos encontrados, son: nitrofurantoina, norfloxacina, amikacina, netilmicina, gentamicina y ácido nalidíxico.

  9. REVIEW. BACTERIAS ACIDO LÁCTICAS: PAPEL FUNCIONAL EN LOS ALIMENTOS BACTÉRIAS ÁCIDO LÁCTICAS: PAPEL FUNCIONAL NOS ALIMENTOS REVIEW LACTIC ACID BACTERIA: FUNCTIONAL ROLE IN THE FOODS

    Directory of Open Access Journals (Sweden)

    RICARDO ADOLFO PARRA HUERTAS

    2010-06-01

    Full Text Available Las bacterias ácido lácticas han sido importantes en los alimentos por siglos por su considerable contribución al valor de los productos. Debido a varias de sus propiedades metabólicas, las bacterias ácido lácticas desempeñan un papel importante en la industria alimentaria, por su contribución significante al sabor, olor, textura, características sensoriales, propiedades terapéuticas y valor nutricional de los productos alimentarios. Este grupo está compuesto de un número de géneros incluyendo Lactococcus, Lactobacillus, Enterococcus, Streptococcus, Leuconostoc y Pediococcus. Algunos de los metabolitos producidos por las este tipo de bacterias son ácidos orgánicos, sustancias preservantes, polisacáridos, vitaminas, endulzantes, olores y sabores entre otros. Esta revisión se enfoca en estudiar la importancia de las bacterias acido lácticas en los alimentos.As bacterias ácido lácticas têm sido importantes nos alimentos por séculos pela sua considerável contribuição ao valor dos produtos. Devido a varias das suas propriedades metabóllcas, as bacterias ácido lácticas desempenham um papel importante na industria alimentar, pela sua contribulção significante ao sabor, cheiro, textura, características sensoriais, propriedades terapêuticas e valor nutrlcional dos produtos alimentar. Este grupo está constituido de um número de gêneros incluindo Lactococcus, Lactobaclllus, Enterococcus, Etreptococcus, Leuconostoc e Pediococcus. Alguns dos metabolltos produzidos por este tipo de bacterias são ácidos orgãnicos, sustãncias preservadoras, poli-sacáridos, vitaminas, adoçantes, cheiros e sabores entre outros. Esta revisão se enfoca em estudar a importãncia das bacterias ácido lácticas nos alimentos.Lactic acid bacteria have been important in food for centuries for their significant contribution to product value. Because several of its metabolic properties, lactic acid bacteria play an important role in the food

  10. Efecto sobre la viabilidad celular de una nueva serie de espirosteroides sintéticos en células PC12

    Directory of Open Access Journals (Sweden)

    Laura García-Pupo

    2013-03-01

    Full Text Available Introducción: la diosgenina y sus derivados se han descrito como potentes inhibidores de la proliferación en varias líneas tumorales. Sin embargo otras moléculas relacionadas estructuralmente con dichos derivados, se han reportado como candidatos terapéuticos y otras de ellas se incluyen en alimentos de consumo humano. Objetivo: el presente trabajo evalúa el efecto sobre la viabilidad celular de una nueva serie de espiroesteroides sintéticos derivados de la diosgenina, en células tipo neurales PC12. Métodos: la viabilidad de los cultivos de PC12 se determinó mediante el ensayo de MTT y se calcularon descriptores moleculares teóricos como la lipofilicidad (logP virtual y la superficie de área polar (SAP, con el objetivo de establecer relaciones estructura-actividad. Resultados: nuestros resultados demuestran que solo el acido taurodesoxicólico disminuye de manera significativa la viabilidad celular. Más aun, dicha molécula presenta valores menores y mayores de logP virtual y SAP, respectivamente, respecto al resto de los esteroides de la serie. Conclusiones: los resultados anteriores avalan el estudio del acido taurodesoxicólico como potencial inhibidor de la proliferación celular y al resto de las moléculas de la serie como candidatos neuroprotectores a evaluar en esta misma línea celular y dosis de tratamiento.

  11. A comparison of exogenous and endogenous CEST MRI methods for evaluating in vivo pH.

    Science.gov (United States)

    Lindeman, Leila R; Randtke, Edward A; High, Rachel A; Jones, Kyle M; Howison, Christine M; Pagel, Mark D

    2018-05-01

    Extracellular pH (pHe) is an important biomarker for cancer cell metabolism. Acido-chemical exchange saturation transfer (CEST) MRI uses the contrast agent iopamidol to create spatial maps of pHe. Measurements of amide proton transfer exchange rates (k ex ) from endogenous CEST MRI were compared to pHe measurements by exogenous acido-CEST MRI to determine whether endogenous k ex could be used as a proxy for pHe measurements. Spatial maps of pHe and k ex were obtained using exogenous acidoCEST MRI and an endogenous CEST MRI analyzed with the omega plot method, respectively, to evaluate mouse kidney, a flank tumor model, and a spontaneous lung tumor model. The pHe and k ex results were evaluated using pixelwise comparisons. The k ex values obtained from endogenous CEST measurements did not correlate with the pHe results from exogenous CEST measurements. The k ex measurements were limited to fewer pixels and had a limited dynamic range relative to pHe measurements. Measurements of k ex with endogenous CEST MRI cannot substitute for pHe measurements with acidoCEST MRI. Whereas endogenous CEST MRI may still have good utility for evaluating some specific pathologies, exogenous acido-CEST MRI is more appropriate when evaluating pathologies based on pHe values. Magn Reson Med 79:2766-2772, 2018. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

  12. Diseño de una planta de producción de ácido l-glutamático a partir de melazas de remolacha azucarera

    OpenAIRE

    San José García, Pablo

    2014-01-01

    INTRODUCCIÓN El ácido L-glutámico es uno de los aminoácidos con mayor demanda a nivel mundial, su producción supera los 1,5 millones de toneladas al año. Es un precursor de Glutamato Monosódico el cual es bastamente utilizado en la industria alimentaria como aditivo saborizante. En el Presente proyecto de fin de carrera se realiza un diseño preliminar de una Planta de producción de acido glutámico por la via fermentativa , utilizando como microorganismo a la bacteria ...

  13. A method for the determination of ascorbic acid using the iron(II)-pyridine-dimethylglyoxime complex

    Energy Technology Data Exchange (ETDEWEB)

    Arya, S. P.; Mahajan, M. [Haryana, Kurukshetra Univ. (India). Dept. of Chemistry

    1998-05-01

    A simple and rapid spectrophotometric method for the determination of ascorbic acid is proposed. Ascorbic acid reduces iron (III) to iron (II) which forms a red colored complex with dimethylglyoxime in the presence of pyridine. The absorbance of the resulting solution is measured at 514 nm and a linear relationship between absorbance and concentration of ascorbic acid is observed up to 14 {mu}g ml{sup -1}. Studies on the interference of substances usually associated with ascorbic acid have been carried out and the applicability of the method has been tested by analysing pharmaceutical preparations of vitamin C. [Italiano] Si propone un rapido e semplice metodo spettrofotometrico per la determinazione dell`acido ascorbico. L`acido ascorbico riduce il ferro(III) a ferro(II) che forma con la dimetilgliossima, in presenza di piridina, un complesso colorato in rosso. L`assorbanza della soluzione risultante e` misurata a 514 nm e si ottiene una relazione lineare tra assorbanza e concentrazione dell`acido ascorbico fino a 14 {mu}g ml{sup -1}. Si sono condotti studi sugli interferenti usualmente associati all`acido ascorbico ed e` stata valutata l`applicabilita` del metodo all`analisi di preparati farmaceutici di vitamina C.

  14. Changes of arterial blood pressure, heart rate, internal body temperature, and blood acido-basic balance in the unanaesthetized rabbit following whole-body gamma irradiation at a mean absorbed dose of 250 rads

    Energy Technology Data Exchange (ETDEWEB)

    Dufour, R.; Court, L.

    1973-09-01

    The general effects of whole-body gamma -irradiation at a mean absorbed dose of 250 rads were studied simultaneously in the unanaesthetized rabbit for 48 hours. They occurred early, with the following characteristics: arterial blood pressure decreased steadily as early as the 2nd hour and reached its minimum value on the 5th hour with a decrease of about 14%; it remained low during the following two days. Heart rate increased during the first hour, was the highest by the end of the second hour, and resumed normal value on the 24th hour. Internal body temperature increased during the 1st hour and was maximum by the end of the 2nd hour, with a mean increase of 1.2 deg C; hyperthermia steadily decreased between the 4th and the 6th hours and had completely disappeared by the 24th hour. Respiratory alkalosis is shown in the acido-basic balance by a raise of pH, a decrease of PCO/sub 2/ and arterial blood bicarbonates. These various changes seem to indicate a double origin, both central and peripheral. (FR)

  15. Performance assessment of the catalyst ZnAl{sub 2}O{sub 4} and Cu/ZnAl{sub 2}O{sub 4} esterification reaction fatty acid in biodiesel; Avaliacao do desempenho do catalisador ZnAl{sub 2}O{sub 4} e Cu/ZnAl{sub 2}O{sub 4} na reacao de estereficacao de acidos graxos em biodiesel

    Energy Technology Data Exchange (ETDEWEB)

    Feitosa, A.C.; Dantas, J.; Costa, A.C.M.F., E-mail: alexcaval2@hotmail.com [Universidade Federal de Campina Grande (UFCG), PB (Brazil). Departamento de Engenharia de Materiais; Barbosa, D.C.; Meneghetti, S.M.P. [Universidade Federal de Alagoas (UFAL), Maceio, AL (Brazil). Dept. de Quimica

    2012-07-01

    This study aims to evaluate the performance of the Cu/ZnAl{sub 2}O{sub 4} and ZnAl{sub 2}O{sub 4} methyl esterification of fatty acids of soybean oil into biodiesel. The ZnAl{sub 2}O{sub 4} was synthesized by combustion reaction and then the sample was wet impregnated with a copper source. The samples were characterized by XRD, SEM, textural analysis and catalytic tests bench. The characterization results showed that the samples showed characteristic diffraction peaks spinel, with the characteristic of mesoporous material (10-250 Å), particles in the form of blocks and slabs of hard point. The results showed that the conversion impregnation of copper has increased by 17% conversion to biodiesel. (author)

  16. Soil decontamination at the Montevecchio-Levante mine site with experimental washing and leaching techniques

    Energy Technology Data Exchange (ETDEWEB)

    Dessi, R. [Progemisa SpA, Cagliari (Italy); Fadda, S.; Peretti, R.; Zucca, A. [CSGM, Centro Studi Germinerari e Mineralurgici del CNR, Cagliari (Italy); Serci, A. [Digita, Dipt. di Geoingegneria e Tecnologie Ambientali, Cagliari (Italy)

    2000-12-01

    The soils in the neighbourhood of the Rio Montevecchio-Sitzerri, a stream that flows in the valley below the tailings pond of the Montevecchio-Levante mineral processing plant (SW Sardinia, Italy) are severely contaminated by heavy metals, to the extent that traditional land uses are compromised. Consequently urgent measures are needed both to abate the pollution at source and rehabilitate the contaminated land. This paper is concerned with the problem of soil decontamination using washing and leaching techniques. Laboratory experiments have been conducted in mechanically agitated reactors, using citric acid and acetic acid solutions and brine of hydrochloric acid and calcium chloride. The influence of both reagent concentration and solid-to-liquid ratio has been assessed, and in the most significant cases, the attack kinetics has been determined. The tests showed the brine to be the most effective for removing metals from the soils. Based on the findings of the investigations, the possibility of decontamination by heap leaching has been simulated in the laboratory using the column technique. [Italian] I suoi circostanti il Rio Montevecchio-Sitzerri, che scorre a valle del bacino di decantazione degli sterili dell'impianto di trattamento dei minerali di Montevecchio-Levante (Sardegna Centro-Occidentale), sono caratterizzati da un elevato contenuto di metalli pesanti, che ne pregiudicano gli usi tradizionali. Si rende percio' improrogabile sia la necessita' di intervenire sulle cause all'origine della contaminazione, sia di bonificare i suoli in questione al fine di recuperarli a nuovi usi. La memoria intende portare un contributo alle relative problematiche affrontando la possibilita' di decontaminazione mediante tecniche di lavaggio e lisciviazione. La sperimentazione di laboratorio e' stata condotta in reattori ad agitazione meccanica, utilizzando soluzioni con acido citrico, acido acetico ed una salamoia costituita da acido

  17. Nucleic Acids and Protein Metabolism of Bone Marrow Cells Studied by Means of Tritiumlabelled Precursors; Etude du Metabolisme des Acides Nucleiques et des Proteines dans les Cellules de la Moelle Osseuse, a l'Aide de Precurseurs Trities; 0418 0437 0443 0414 ; Estudio con Ayuda de Precursores Tritiados del Metabolismo de los acidos Nucleicos y de las Proteinas en las Celulas de la Medula Osea;

    Energy Technology Data Exchange (ETDEWEB)

    Gavosto, F. [Istituto di Clinica Medica Generale e Centro di Studi Fisico-Biologici, Universita de Turin, Turin (Italy)

    1962-02-15

    . L'auteur examine ensuite la diminution et la dissociation du metabolisme de l'ARN et des proteines, dans les cellules de sujets atteints de leucemie aiguee, par rapport aux anomalies bien connues que presente le processus de maturation de ces cellules. (author) [Spanish] El autor examina las ventajas que presenta el empleo de los compuestos marcados con tritio en la tecnica autorradiografica. En efecto, los electrones emitidos por el tritio tienen una energia maxima de 0,018 MeV, que corresponde, aproximadamente, a un alcance de 1 miera en una emulsion fotografica y permiten, por lo tanto, lograr el maximo poder de resolucion al nivel celular y subcelular. Ello es particularmente util para estudiar fenomenos metabolicos en tejidos que se componen, como en el caso de la medula osea, de celulas de varios tipos en diversos estados de diferenciacion. Esta tecnica se ha aplicado al estudio del metabolismo de los acidos nucleicos y de las proteinas en las celulas normales y leucemicas de la medula osea. El metabolismo del acido desoxirribonucleico se ha estudiado utilizando un precursor especifico, la timidina-{sup 3}H. Comparando los elementos normales y leucemicos que han alcanzado un grado de madurez analogo, se han observado diferencias significativas en el porcentaje de celulas marcadas. Especialmente, en los casos de leucemia aguda, se ha comprobado que la incorporacion de timidina en las celulas leucemicas disminuye muy notablemente. Se estima que estos resultados constituyen una prueba de que la capacidad de proliferacion de estas celulas disminuye en comparacion con la de los mieloblastos normales. Por este mismo procedimiento, se ha estudiado el metabolismo del acido ribonucleico y de las proteinas, utilizando como precursores uridina-{sup 3}H, leucina-{sup 3}H y fenilalanina-{sup 3}H. Actualmente, en biologia celular se admite sin reservas la existencia de una estrecha relacion entre el metabolismo del acido ribonucleico y el de las proteinas. Ademas, se ha

  18. The use of peracetic acid in drinking water systems: flow tests; L'acido peracetico in potabilizzazione: prove in flusso

    Energy Technology Data Exchange (ETDEWEB)

    Ragazzo, P. [Consorzio per l' Acquedotto del Basso Piave, San Dona' di Piave, VE (Italy); Navazio, G. [Padua Univ., Padua (Italy). Dipt. dei Processi Chimici dell' Ingegneria; Cavadone, A. [Solvay Chimica Italia S.p.A., Milan (Italy)

    2000-09-01

    In a previous research, a preliminary study was carried out on the disinfection efficiency of peracetic acid (PAA), comparing it to that of other disinfectants that are typically used, in batch tests with dosage values ranging from 0.5 to 5 ppm. The study was carried out on samples of water collected from several significant points of the treatment process at the main water treatment plant in Jesolo (Venice, Italy). On the basis of results (basically positive at that time) obtained from these tests, a 400 litre/hour pilot plant was built, as a lower scale reproduction of the drink water treatment system mentioned earlier, in order to study the characteristics of PAA even in tests that could more realistically simulate the flow of water along the process. These tests essentially confirmed the kinetics of the spontaneous hydrolysis to CH{sub 3} COOH+H{sub 2}O{sub 2} and those of dismutation to CH{sub 3}COOH+O{sub 2}, with half-life time values ranging from 3 to 12 hours, depending on the characteristics of the water (especially the pH factor) and the PAA concentration values. [Italian] In un precedente lavoro e' stato effettuato un preventivo studio sull'efficienza disinfettiva dell'acido peracetico, anche in confronto con gli altri piu' usuali disinfettanti, in prove condotte in batch, con dosaggi compresi tra 0.5 e 5 ppm, su campioni di acqua prelevati dai diversi punti significativi della linea di trattamento della centrale di Jesolo (Torre Caligo), gestita dal Consorzio Acquedottistico del Basso Piave di S. Dona' di Piave (Venezia). Sulla base dei risultati, sostanzialmente positivi, e' stato costruito un impianto pilota da 400l/h, riproducente, in scala, la linea di potabilizzazione su ricordata, per studiare le caratteristiche del PAA anche in prove piu' probanti condotte in flusso. In tali prove sono state sostanzialmente riconfermate le cinetiche delle reazioni spontanee di dirolisi a CH{sub 3}COOH+H{sub 2}O{sub 2} e di

  19. Identificación de defensas inducibles a áfidos en cebadas pre-comerciales

    OpenAIRE

    Caridad, Alejandro; Saldúa, Vilma Luciana; Castro, Ana María

    2018-01-01

    Las plantas tienen la capacidad de adaptarse a situaciones de estrés mediante la expresión de genes implicados en mecanismos de defensa, que pueden ser constitutivos o inducibles, dependiendo si se expresan permanentemente o no. Detrás de la regulación de estos mecanismos se encuentran las hormonas, moléculas señalizadoras que comunican los distintos tejidos de la planta entre sí. Ante el ataque de insectos, el Acido Jasmónico (AJ) y el Acido Salicílico (AS) juegan un papel preponderante en l...

  20. POLYETHYLENEIMINE (PEI ON SILICA AS CATALYST IN KNOEVENAGEL AND MICHAEL REACTIONS

    Directory of Open Access Journals (Sweden)

    FATIHA ZAOUI

    2017-03-01

    Full Text Available After the synthesis of polyethylenimine supported on silica, it has been used as a new and efficient catalyst in Knoevenagel and Michael condensations. The presence of the polyethylenimine in the catalytic system together with silica displays an acido-basic character allows a better catalytic activity in the condensations. Carried out under microwave irradiation, without organic solvent and during short time, the syntheses are respectful towards green chemistry. The solid catalyst can be easily reused. This catalyst has the acido-basic character at the same time.

  1. Evaluación de la educación nutricional y un suplemento para prevenir la anemia durante la gestación.

    Directory of Open Access Journals (Sweden)

    Beatriz Elena Parra

    2005-06-01

    Full Text Available Introducción. Las deficiencias de hierro y acido fólico son la causa de graves problemas de salud en la mujer gestante y en el niño, con implicaciones negativas para el desarrollo económico y social de los países. Objetivos. Evaluar los cambios de conocimientos sobre funciones, alimentos fuentes y biodisponibilidad del hierro y folatos, el consumo y la tolerancia de un suplemento y el comportamiento de los índices globulares en gestantes del programa prenatal de la Empresa Social del Estado Hospital Gilberto Mejía Mejía de Rionegro, Antioquia, Colombia, entre abril de 2002 y abril de 2003. Materiales y métodos. Estudio cuasi experimental en una muestra de 42 madres, seleccionada por conveniencia, con una confianza del 95%. La intervención fue un programa de educación nutricional y el suministro de un suplemento con 60 mg de hierro elemental, 400 J.g de acido fólico y 70 mg de vitamina C, elaborado para la investigación por el Laboratorio Profesional Farmacéutico, LAPROFF. El efecto de la intervención se midió en los cambios de conocimientos relacionados con las practicas que modifican la biodisponibilidad y el consumo de alimentos fuentes de estos nutrientes, en la tolerancia y la adherencia al suplemento y en la modificación de variables hematológicas: hemoglobina, hematocrito y ferritina. Resultados. Hubo cambios positivos de conocimientos sobre cómo mejorar las practicas alimentarias y la ingestión del suplemento; el 94,4% de las participantes no presentó anemia al finalizar la gestación. Conclusión. Estos resultados concuerdan con otros provenientes de poblaciones similares; se justifica implementar esta estrategia integrada en los programas de control prenatal de Colombia.

  2. In vitro activity of 2-pyridinecarboxylic acid against trypanosomes of the subgenus Schizotrypanum isolated from the bat Phyllostomus hastatus = Atividade in vitro do ácido 2-piridinocarboxílico em tripanossoma do subgênero Schizotrypanum isolado do morcego Phyllostomus hastatus

    Directory of Open Access Journals (Sweden)

    Paulo Roberto Ceridóreo Corrêa

    2011-09-01

    Full Text Available The effect of 2-pyridinecarboxylic acid (picolinic acid on trypanosomes of the subgenus Schizotrypanum isolated from the bat Phyllostomus hastatus was determined in this study. Picolinic acid, at 50 ƒÊg mL-1, inhibited epimastigote growth by 99% after 12 days incubation. In addition, trypomastigote motility decreased by 50% after 6h and completely after 24h in the presence of 50 ƒÊg mL-1 picolinic acid. The 50% cytotoxic concentration on HEp-2 cell line was275 ƒÊg mL-1 after 4 days incubation. Altogether, these results indicate higher toxicity against trypanosomes. The inhibitory effect of picolinic acid on epimastigote growth can be partially reversed by nicotinic acid and L-tryptophan, suggesting a competitive inhibition. Furthermore, two anti-Trypanosoma (Schizotrypanum cruzi drugs were also evaluated with regard to bat trypanosome growth. Benznidazole, at 50 ƒÊg mL-1, inhibited epimastigote growth by 90% after 12 days incubation. Nifurtimox, at the same concentration, caused 96% growth inhibition after four days incubation. Corroborating a previous study, bat trypanosomes are a good model for screening new trypanocidal compounds. Moreover, they can be used to study many biological processes common to human pathogenic trypanosomatids.O efeito do acido 2- piridinocarboxilico (acido picolinico sobre um tripanossoma do subgenero Schizotrypanum isolado do morcego Phyllostomus hastatus foi determinado neste estudo. O acido picolinico, na concentracao de 50 ƒÊg mL-1, inibiu 99% do crescimento de epimastigotas apos 12 dias de incubacao. Alem disso, houve um decrescimo de 50 e 100% na mobilidade dos tripomastigotas apos 6 e 24h, respectivamente, em presenca de acido picolinico na concentracao de 50 ƒÊg mL-1. A concentracao citotoxica 50% para celulas HEp-2 foi de 275 ƒÊg mL-1 apos quatro dias de incubacao. Esses resultados indicam maior toxicidade contra os tripanossomas. O efeito inibitoriodo acido picolinico sobre o crescimento de

  3. Al-Qurû’ fi Al-Qur’an ‘Inda Al-Anbary fi Al-Adhdâd

    Directory of Open Access Journals (Sweden)

    Raushani Azza

    2018-03-01

    Full Text Available This study examines about the term al-Qurû in the Qur’an. Al-Qurû is one of the most popular discussions among muslim scholars and mufasir, both in terms of language and fiqh. However, there is a bate among muslim scholar and mufasir about the meaning of al-Qurû. It’s because al-Qurû is one of the sentence of al-Adhdâd wich has two meaning, especially in the Qur’an, namely haid (menstruation and thahr. One of the most popular muslim scholar who concern in Qur’an and Arabic is al-Anbari with his book al-Adhdâd. Al-Anbari explains that Qurû has two meanings, First, al-Qurû in etymology is the form of Jama’ from aqra and qurû. Second, al-Qurû has a meaning of menstruation, thahr, or the period of iddah as a sign of being allowed to remarry after certain period of time.

  4. Wastewater disinfection with peracetic acid and UV; La disinfezione di acque reflue con acido peracetico e raggi ultravioletti

    Energy Technology Data Exchange (ETDEWEB)

    Caretti, C.; Lubello, C. [Florence Univ., Florence (Italy). Dipt. di Ingegneria Civile

    2001-06-01

    Was investigated the synergy between UV and peracetic acid (PAA) through a five months on-site experimental study in a pilot plant fed by the secondary effluent of the central wastewater treatment plant of Pistoia, Italy. This experiment is a part of a larger research project on advanced treatment for municipal wastewater reuse in agriculture. Because of Italy's strict limits on unrestricted wastewater reuse in agriculture (2 CFU total coliform/100 ml), a very high degree of disinfection is necessary. In the investigated experimental conditions, it has been impossible to meet such values through an exclusive use of UV irradiation (the UV unit reaches at most 4 Log inactivation). Low levels of PAA greatly enhance the decline of indicator levels, but higher unsustainable doses are required to hit the Italian limit. Through a poor amount of information on the subject was available in literature, it was tried to find out how the disinfection efficiency could improve by simultaneously using UV and PAA. It was found out that a combined treatment is satisfactory and that it is more advantage of the hydroxyl radicals formation due to the PAA photo lysis. The application of 2 ppm of PAA with an UV dose of 192 mWscm{sup -}2 is enough to meet the Italian limit. [Italian] Nel presente articolo si riportano i risultati di uno studio sulla sinergia tra acido peracetico (PAA) e raggi ultravioletti nella disinfezione delle acque reflue secondarie; le prove sono state effettuate su scala pilota, presso l'impianto centrale di Pistoia. Tale sperimentazione fa parte di un piu' ampio progetto di ricerca sulla possibilita' di riutilizzare le acque reflue a scopo irriguo; per rispettare i limiti estremamente stringenti imposti dalla normativa italiana per l'irrigazione (2 CFU Coliformi totali/100 ml, nel caso di irrigazione illimitata), e' necessario garantire efficienze di disinfezione molto elevate. Nelle condizioni sperimentali considerate, non e

  5. Al-Âyah al-Mutasyâbihât al-Lafzhiyyah fi Sûrah al-An’âm ‘Inda al-Kirmâny

    Directory of Open Access Journals (Sweden)

    Hikmatiar Pasya

    2017-07-01

    Full Text Available This paper discusses about the verses of mutasyâbihât in the Quran. The debate of this verses caused various opinions. The meaning of the mutasyâbihât in this paper is the similarity and difference of the words in the Qur'an. Mufasir have different opinion about the meaning of the verse of mutasyâbihât al-lafdzi. In addition, many Hufadz of the Quran who are confused from one verse to another, or one chapter to another. It’s because similarity of verses in the Qur'an with other verses. So the writer wants to explain the verses mutasyâbihât al-lafdzi in the perspective of Hamzh al-Karmani in Surah al-An'âm. In this discussion the author discovers some passages in mutasyâbihât al-lafdzi, namely Asrâru al-balaghah fi mutasyabih al-lafdzi, Asrar al-balaghah fi mutasyabih al-hurf, and murâ'ah al-ikhtilâfmurâd bi al-lafdzi al-mukarrar.

  6. Ensamble, diseño y ensayo de un potenciometro computarizado

    Directory of Open Access Journals (Sweden)

    Rocio Bojacá B.

    2010-05-01

    Full Text Available Se ha ensamblado una unidad potenciométrica (U.P. para mediciones de pH y fuerza electromotriz en procesos estáticos y de titulación. La reproducibilidad en mediciones de pH es de 0.013 unidades de pH y 0.01 mi en volumen. El potenciómetro consta de un acoplador de impedancias, un amplificador de ganancia variable y una interfase (convertidor análogico/Digital. El computador utilizado es un Kaypro II y et graficador es Phillips 8154. El software desarrollado incluye tos programas calibra (estandarización de la U.P. en dos pH diferentes, titula, tit140 y Tit1400 (titulaciones ácido-base y Redox y Ajus (cálculos de volimen como función de pH o potencial. En los ensayos de la U.P. se insiste en las diferencias que se observan en las gráficas cuando se titula un Acido Fuerte o un Acido Débil. En el primer caso se propone la denominación Zona Estabilizadora y en et segundo Zona Buffer o amortiguadora, donde se forma el típico sistema Acido/Sal.

  7. ELIMINACION DEL COLORANTE NEGRO ACIDO 194 DESDE AGUAS RESIDUALES TEXTILES MEDIANTE ELECTROCOAGULACION

    OpenAIRE

    VIDAL FUENTES, JORGE ARTURO

    2013-01-01

    Diariamente, las industrias textiles descargan grandes volúmenes de aguas que contienen altas concentraciones de colorantes y aditivos, los cuales ocasionan daños considerables al medio ambiente. Muchos de estos colorantes son estables a la luz y a la biodegradación, siendo considerados como compuestos orgánicos persistentes (COPs). Es por esto que es necesario aplicar métodos que permitan la eliminación de estos contaminantes desde las aguas. Una metodología efectiva para la eliminación de C...

  8. Diffusion-induced quadrupole relaxation of 27Al nuclei in dilute Al-Ti, Al-Cr, Al-Mn, and Al-Cu alloys at high temperatures

    International Nuclear Information System (INIS)

    Bottyan, L.; Beke, D.L.; Tompa, K.

    1983-01-01

    The temperature dependence of the laboratory frame spin-lattice relaxation time of 27 Al nuclei is measured in 5N Al and in dilute Al-Ti, Al-Cr, Al-Mn, and Al-Cu alloys at 5.7 and 9.7 MHz resonance frequencies. The relaxation in pure aluminium is found to be purely due to the conduction electrons. An excess T 1 -relaxation contribution is detected in all Al-3d alloys investigated above 670 K. The excess relaxation rate is proportional to the impurity content and the temperature dependence of the excess contribution is of Arrhenius-type with an activation energy of (1.3 +- 0.3) eV for all of the investigated alloys. The relaxation contribution is found to be quadrupolar in origin and is caused by the relative diffusional jumps of solute atoms and Al atoms relatively far from the impurity. (author)

  9. Interfacial phenomena in the reactions of Al-B, Al-Ti-B, and Al-Zr-B alloys with KF-AlF3 and NaF-AlF3 melts

    International Nuclear Information System (INIS)

    Lee, M.S.; Terry, B.S.; Grieveson, P.

    1993-01-01

    The interfacial phenomena occurring during the contacting of liquid Al-B, Al-Ti-B, and Al-Zr-B melts with KF-AlF 3 liquid fluxes have been investigated by optical examination of quenched metal drops previously immersed in the liquid fluxes. Reactions in the Al-B/KF-AlF 3 system involve the formation of metastable AlB 12 at the metal/flux interface. At high KBF 4 levels in the flux, the AlB 12 is dispersed in the flux and also at low KBF 4 levels in the metal. Reactions in the Al-Ti-B/KF-AlF 3 system involve the formation of TiB 2 , which may be dispersed in either the metal or the flux depending upon the composition of the flux. The results obtained for the Al-Ti-B/NaF-AlF 3 and Al-Zr-B/KF-AlF 3 systems were similar to those observed for the Al-Ti-B/KF-AlF 3 system

  10. Synthesizing (ZrAl3 + AlN)/Mg-Al composites by a 'matrix exchange' method

    Science.gov (United States)

    Gao, Tong; Li, Zengqiang; Hu, Kaiqi; Han, Mengxia; Liu, Xiangfa

    2018-06-01

    A method named 'matrix exchange' to synthesize ZrAl3 and AlN reinforced Mg-Al composite was developed in this paper. By inserting Al-10ZrN master alloy into Mg matrix and reheating the cooled ingot to 550 °C, Al and Mg atoms diffuse to the opposite side. As a result, liquid melt occurs once the interface areas reach to proper compositions. Then dissolved Al atoms react with ZrN, leading to the in-situ formation of ZrAl3 and AlN particles, while the Al matrix is finally replaced by Mg. This study provides a new insight for preparing Mg composites.

  11. Coupled growth of Al-Al2Cu eutectics in Al-Cu-Ag alloys

    International Nuclear Information System (INIS)

    Hecht, U; Witusiewicz, V; Drevermann, A

    2012-01-01

    Coupled eutectic growth of Al and Al 2 Cu was investigated in univariant Al-Cu-Ag alloys during solidification with planar and cellular morphology. Experiments reveal the dynamic selection of small spacings, below the minimum undercooling spacing and show that distinct morphological features pertain to nearly isotropic or anisotropic Al-Al 2 Cu interfaces.

  12. AL ITTIJAHAT AL MUNHARIFAH FI AT TAFSIR LI BADLI ASHAB AL MADZAHIB AL NAHWIYYAH WA BADL MAN YAJHALUNA QAWAID AL LUGHAH AL ARABIYYAH FI NADHAR MUHAMMAD HUSAIN AL DZAHABIY

    Directory of Open Access Journals (Sweden)

    Misbakhudin Misbakhudin

    2017-06-01

    Full Text Available One of the most precious achievement in qur’anic studies was the book of Al-Ittijâhât al-Munharifah fî al-Tafsîr: Dawâfi’uha wa Daf’uha written by A great Islamic scholar, Muhammad Husein al-Dzahabî. He was succeeded in discussing several issues of corruptions of the exegesis of the holy Qur’an. This article is aimed to explain and to describe his analysis toward several corrupted linguist interpretations in their originations and such corrupted linguistic interpretations of the holy Qur’an which are ignoring Arabic structures and grammers

  13. Familial ALS

    Science.gov (United States)

    Boylan, Kevin

    2015-01-01

    Synopsis Genes linked to ALS susceptibility are being identified at an increasing rate owing to advances in molecular genetic technology. Genetic mechanisms in ALS pathogenesis appear to exert major effects in ~10% of patients, but genetic factors at some level may be important components of disease risk in most ALS patients. Identification of gene variants associated with ALS has informed concepts of the pathogenesis of ALS, aided the identification of therapeutic targets, facilitated research to develop new ALS biomarkers, and supported the establishment of clinical diagnostic tests for ALS-linked genes. Translation of this knowledge to ALS therapy development is ongoing. PMID:26515623

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

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    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.

  15. Transient oxidation of Al-deposited Fe-Cr-Al alloy foil

    International Nuclear Information System (INIS)

    Andoh, A.

    1997-01-01

    The oxide phases formed on an Al-deposited Fe-Cr-Al alloy foil and an Fe-Cr-Al alloy foil of the same levels of Al and (La+Ce) contents, and their oxidation kinetics have been studied in air at 1173 and 1373 K using TGA, XRD and SEM. Al deposition promotes the growth of metastable aluminas (θ-Al 2 O 3 , γ-Al 2 O 3 ). Scales consisting of θ-Al 2 O 3 and a small amount of α-Al 2 O 3 develop on the Al-deposited foil at 1173 K and exhibit the whisker-type morphology. In the early stage of oxidation at 1373 K, thick scales consisting of θ-Al 2 O 3 and α-Al 2 O 3 grow rapidly on the Al-deposited foil. The transformation from θ-Al 2 O 3 to α-Al 2 O 3 is very fast, and the scales result in only α-Al 2 O 3 . In contrast, α-Al 2 O 3 scales containing a minor amount of FeAl 2 O 4 develop on the alloy foil. The growth rate of α-Al 2 O 3 scales on the Al-deposited foil is smaller than that on the alloy foil and very close to that on NiAl at 1373 K. (orig.)

  16. Proton irradiation studies on Al and Al5083 alloy

    Science.gov (United States)

    Bhattacharyya, P.; Gayathri, N.; Bhattacharya, M.; Gupta, A. Dutta; Sarkar, Apu; Dhar, S.; Mitra, M. K.; Mukherjee, P.

    2017-10-01

    The change in the microstructural parameters and microhardness values in 6.5 MeV proton irradiated pure Al and Al5083 alloy samples have been evaluated using different model based techniques of X-ray diffraction Line Profile Analysis (XRD) and microindendation techniques. The detailed line profile analysis of the XRD data showed that the domain size increases and saturates with irradiation dose both in the case of Al and Al5083 alloy. The corresponding microstrain values did not show any change with irradiation dose in the case of the pure Al but showed an increase at higher irradiation doses in the case of Al5083 alloy. The microindendation results showed that unirradiated Al5083 alloy has higher hardness value compared to that of unirradiated pure Al. The hardness increased marginally with irradiation dose in the case of Al5083, whereas for pure Al, there was no significant change with dose.

  17. PEMBARUAN MASLAḤAH DALAM MAQĀṢID AL- SHARĪ‘AH: TELAAH HUMANISTIS TENTANG AL-KULLIYYĀT AL-KHAMSAH

    Directory of Open Access Journals (Sweden)

    Zaenuddin Mansyur

    2012-06-01

    Full Text Available Abstract:   In order to answer a variety of issues faced by human being in the current era, such as human rights abuses, social disintegration, and terrorism, the renewal of Islamic law in the level of theoretical and practical aspects is very urgent. This paper aims to examine one of the Islamic legal reform efforts, namely to build a more technical understanding of the concept of maṣlaḥah contained in the maqāṣīd sharī‘ah, called the al-kulliyat al-khamsah. Therefore, the concept of maṣlaḥah in ḥifẓ al-dīn is technically defined as al-ḥurriyah al-i‘tiqād (freedom of religion and schools; in ḥifẓ al-nafs as al-karamat al-insān (human being breeding; in ḥifẓ al-nasl as ḥifẓ al-usrah (wholeness and harmony of the family; in ḥifẓ al-māl as al-taḍammun al-insān (social solidarity , and in ḥifẓ al-‘aql as al-ḥuqūq as al-tarbiyāt (increasing human resources quality.Abstrak: Demi menjawab aneka persoalan zaman yang dihadapi manusia era sekarang, seperti penyelewengan terhadap HAM, disintegrasi sosial, dan terorisme, maka pembaharuan hukum Islam dalam tataran teoretis dan praktis urgen dilakukan. Tulisan ini bertujuan untuk mengkaji salah satu upaya pembaruan hukum Islam, yaitu membangun pemahaman yang lebih teknis terhadap konsep maṣlaḥah yang terkandung dalam maqāṣīd sharī‘ah, yang disebut dengan al-kulliyāt al-khamsah. Oleh karena itu, konsep maṣlaḥah dalam ḥifẓu al-dīn secara teknis dimaknai sebagai ḥurriyah al-i‘tiqād (kebebasan untuk beragama dan beraliran; dalam ḥifẓu al-nafs sebagai al-karāmāt al-insān (pemuliaan kemanusiaan; dalam ḥifẓu al-nasl sebagai ḥifẓu al-usrah (keutuhan dan keharmonisan keluarga; dalam ḥifẓu al-māl sebagai al-taḍammun al-insān (solidaritas sosial; dan dalam ḥifẓu al-‘aql sebagai al-ḥuqūq al-tarbiyāt (peningkatan sumber daya manusia.

  18. Combustion synthesis of AlB2-Al2O3 composite powders with AlB2 nanowire structures

    Science.gov (United States)

    Yang, Pan; Xiao, Guoqing; Ding, Donghai; Ren, Yun; Yang, Shoulei; Lv, Lihua; Hou, Xing

    2018-05-01

    Using of Al and B2O3 powders as starting materials, and Mg-Al alloy as additives, AlB2-Al2O3 composite powders with AlB2 nanowire structures were successfully fabricated via combustion synthesis method in Ar atmosphere at a pressure of 1.5 MPa. The effect of different amount of Mg-Al alloy on the phase compositions and morphology of the combustion products was investigated. The results revealed that AlB2 and Al2O3 increased, whereas Al decreased with the content of Mg-Al alloy increasing. The impurities MgAl2O4 and AlB12 would exist in the sample with adding of 18 wt% Mg-Al alloy. Interestingly, FESEM/TEM/EDS results showed that AlB2 nanowires were observed in the products when the content of Mg-Al alloy is 6 wt% and 12 wt%. The more AlB2 nanowires can be found as the content of Mg-Al alloy increased. And the yield of AlB2 nanowires with the diameter of about 200 nanometers (nm) and the length up to several tens of micrometers (μm) in the combustion product is highest when the content of Mg-Al alloy is 12 wt%. The vapor, such as Mg-Al (g), B2O2 (g), AlO (g) and Al2O (g), produced during the process of combustion synthesis, reacted with each other to yield AlB2 nanowires by vapor-solid (VS) mechanism and the corresponding model was also proposed.

  19. The effects of boron in TiAl/Ti3Al

    International Nuclear Information System (INIS)

    Feng, C.R.; Michel, D.J.; Crowe, C.R.

    1989-01-01

    The authors discuss the TiAl/Ti 3 Al interfacial misfit dislocations structures investigated by TEM in Ti-45Al alloy and Ti-45Al/TiB 2 composite. For TiAl with c/a = 1.02, only a single set of misfit dislocation arrays are crystallographically possible; these were observed in Ti-45Al alloy. However, the observation of three sets of misfit dislocation arrays in the Ti-45Al/TiB 2 composite suggests that the occupation of octahedral sites in the TiAl structure by excess boron was responsible for a decrease in the c/a ratio leading to an increased fcc character of the TiAl at the TiAl/Ti 3 Al interface

  20. 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

  1. 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.

  2. PEMAHAMAN HADITS TARBAWI BURHAN AL ISLAM AL ZARNUJI DALAM KITAB TA’LIM AL MUTA’ALLIM

    Directory of Open Access Journals (Sweden)

    Benny Afwadzi

    2017-01-01

    Full Text Available This paper explores the understanding of tarbawi (education hadith from one of the major influential clerics in the Islamic educational system, especially in pesantren. He is Burhan al Islam al Zarnuji with his landmark book Ta’lim al Muta’allim. The conclusion that can be drawn is that al Zarnuji has shades of sufistical view in understanding tarbawi hadith. This can be seen in his understanding of hadith on obligation to seek knowledge (thalab al ilmi faridhatun ‘ala kulli muslimin wa muslimatin, which is interpreted as ilm al hal, the science concerning the condition of the human religious or simplistically said as the religious sciences; and the hadith of intention of studying (innama al a’malu bi al niyyat with the intention for the sake of the hereafter and religion, not mundane. Such an understanding is not something taken for granted, but it can be reinterpreted and perfected in accordance with the spirit of the times of context.

  3. Calculation of Gibbs energy of Zr-Al-Ni, Zr-Al-Cu, Al-Ni-Cu and Zr-Al-Ni-Cu liquid alloys based on quasiregular solution model

    International Nuclear Information System (INIS)

    Li, H.Q.; Yang, Y.S.; Tong, W.H.; Wang, Z.Y.

    2007-01-01

    With the effects of electronic structure and atomic size being introduced, the mixing enthalpy as well as the Gibbs energy of the ternary Zr-Al-Cu, Ni-Al-Cu, Zr-Ni-Al and quaternary Zr-Al-Ni-Cu systems are calculated based on quasiregular solution model. The computed results agree well with the experimental data. The sequence of Gibbs energies of different systems is: G Zr-Al-Ni-Cu Zr-Al-Ni Zr-Al-Cu Cu-Al-Ni . To Zr-Al-Cu, Ni-Al-Cu and Zr-Ni-Al, the lowest Gibbs energy locates in the composition range of X Zr 0.39-0.61, X Al = 0.38-0.61; X Ni = 0.39-0.61, X Al = 0.38-0.60 and X Zr = 0.32-0.67, X Al = 0.32-0.66, respectively. And to the Zr-Ni-Al-Cu system with 66.67% Zr, the lowest Gibbs energy is obtained in the region of X Al = 0.63-0.80, X Ni = 0.14-0.24

  4. Bipolar characteristics of AlGaN/AlN/GaN/AlGaN double heterojunction structure with AlGaN as buffer layer

    International Nuclear Information System (INIS)

    Peng, Enchao; Wang, Xiaoliang; Xiao, Hongling; Wang, Cuimei; Yin, Haibo; Chen, Hong; Feng, Chun; Jiang, Lijuan; Hou, Xun; Wang, Zhanguo

    2013-01-01

    Highlights: •2DEG and 2DHG coexist in the AlGaN/AlN/GaN/AlGaN DH-structure. •The sheet densities of 2DEG and 2DHG vary with buffer Al content and GaN thickness. •The conditions for the disappearance of 2DHG are discussed. •Increasing buffer Al content provides better electron confinement. •Dislocation scattering is reduced in the DH-structure. -- Abstract: This is a theoretical study of AlGaN/AlN/GaN/AlGaN double heterojunction (DH) structure with AlGaN as buffer layer. Our calculation shows that as the buffer Al content increases, though two-dimensional electron gas (2DEG) sheet density decreases, the channel back-barrier caused by polarization-induced electric field in GaN provides better electron confinement. And under certain conditions the DH-structure shows bipolar characteristics, with an additional two-dimensional hole gas (2DHG) formed at GaN/AlGaN interface. The influence of the buffer Al content and GaN channel thickness on the 2DEG and 2DHG sheet densities are investigated, and the conditions for the disappearance of 2DHG are discussed. Also, the mobility inhibited by dislocation scattering is enhanced in DH-structure due to the enhancement of screening effect of the 2DEG

  5. The code of light: al-ghazali and al-suhrawardi

    OpenAIRE

    Gediminaitė, Barbora

    2017-01-01

    The Code of Light: Al-Ghazali and Al-Suhrawardi The Bachelor’s thesis The Code of Light in Islam: al-Ghazali and al-Suhrawardi presents a comparative study of light. The study analyses the philosophical systems of al-Ghazali and al-Suhrawardi through the reconstruction of the image of light and its operation principles. The main subject of the thesis are the attributes of light. The main problem of the research is the semantics and contextuality of light in Islamic theology and philosophy. Th...

  6. Pemikiran Filosofis Sadra Dalam Tafsir Al-Qur’an Al-Karim : Surah Al-’A‘la

    Directory of Open Access Journals (Sweden)

    Kerwanto Kerwanto

    2014-12-01

    Full Text Available Abstrak : Dalam tafsir atas Surah al-’A‘lā, Mulla Sadra, melalui karyanya Tafsīr al Qur’ān al-Karīm, mengajak jiwa kita berpetualang menuju lapisan makna terdalam untuk mengenali realitas ketauhidan (al- mabdā’, kenabian (shirāth atau nubuwwah dan kebangkitan (ma‘ād dan mengulasnya secara filosofis. Penelitian ini merupakan suatu upaya untuk menggali manfaat dari aspek-aspek penting dari sumber-sumber keagamaan yang tergali dari petunjuk al Qur’an yang berpadu dengan prinsip- prinsip rasional filosofis dan pengalaman mistik (intuitif Sadra. Setiap bab pada tafsir ini diberikan judul dengan tasbīḥ (pernyataan pemujian dan pensucian, dengan tetap memaparkan beragam pokok persoalan terkait metafisika al-Qur’an. Prinsip-prinsip filosofis yang digunakan dalam risalah tafsir ini bisa menjadi salah satu bukti ketidakberjarakan antara filsafat dengan teks-teks keagamaan. Sadra menggunakan metode tafsir yang tetap menerima sisi lahiriah al-Qur’an, dan selanjutnya mencari misteri-misteri, rahasia-rahasia, dan dengan bantuan intelek (akal, intuisi dan iluminasi Tuhan untuk memperoleh realitas-realitas dan makna- makna dibalik selaput ekternalnya (aspek literalnyaKata kunci : Ḥikmah Muta’āliyah, irfan, al-mabdā’, kebangkitan setelah mati, nubuwwah, takwīl, gerak substansial (ḥarakah jawhariyyah, denotasi utama (al-maqshūd al-ashlī, penyempurnaan diri (takammul, tasbīḥ.  Abstract : In his commentary on Surah al-’ A‘lā, Mulla Sadra, through his Tafsīr al-Qur’ān al-Karīm invites our souls to ventureinto the deepest layers of meaning to recognize the reality of Divinity (al- mabdā’, prophethood (Ṣirāṭ or nubuwwah and resurrection (ma‘ād and discusses it in a more philosophical manner. This study is an attempt to explore the benefits of these important aspects of religious sources unearthed from Qur’anic injunctions combined with rational principles of philosophical and mystical experiences

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

    International Nuclear Information System (INIS)

    Ma Xiaoguang; Liu Xiangfa; Ding Haimin

    2009-01-01

    Because flake-like TiAl 3 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 TiAl 3 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

  8. The Radiation Induced Graft Copolymerization of Methacrylic Acid to Nylon; Copolymerisation par greffe de l'acide methacrylique sur le nylon, provoquee par irradiation; Obluchenie vyzyvaet graft-kopolimerizats yu metakrilovoj kisloty v nejlone; Injerto del acido metacrilico en el nylon por copolimerizacion radioinducida

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, R; Thomas, J K

    1960-07-15

    The grafting of methacrylic acid to nylon by the preirradiation technique has been studied. The rate of grafting is appreciably larger than that of homopolymerization. No simple relation exists between reaction rate and total dose. The temperature dependence of the rate of grafting to the fibre, preirradiated in air, indicates that initiation of grafting is likely to take place by decomposition of peroxide groups formed on irradiation. Electrical resistance measurements on the irradiated fibre indicate that this has been reduced by a factor of 10. (author) [French] On a etudie le greffage de l'acide methacrylique sur du nylon par la technique de preirradiation. La vitesse du greffage est sensiblement plus grande que celle de l'homopolymerisation. Il n'existe pas de rapport simple entre la vitesse de reaction et la dose totale. Le fait que la vitesse du greffage sur la fibre, pre-irradiee a l'air, depend de la temperature, indique que l'amorcage de la greffe est susceptible d'etre provoque par la decomposition des groupements de peroxyde formes lors de l'irradiation. Les mesures de resistance electrique effectuees sur la fibre irradiee indiquent que cette resistance a ete reduite au dixieme de la valeur originale. (author) [Spanish] Al estudiar la copolimerizacio n de injerto del acido metacrilico en el nylon por el procedimiento de preirradiacion, los autores comprobaron que la velocidad de injerto es sensiblemente mas elevada que la de homopolimerizacion. No existe una relacion sencilla entre la velocidad de reaccion y la dosis total. La influencia de la temperatura sobre la velocidad de injerto en la fibra previamente irradiada en aire indica que el proceso se inicia por descomposicion de los grupos peroxido formados durante la irradiacion. Las mediciones efectuadas demuestran que la resistencia electrica de la fibra irradiada solo alcanza la decima parte de la correspondiente a la fibra no tratada. (author) [Russian] Bylo provedeno izuchenie prosachivaniya

  9. Liquidus projection of the Nb-Cr-Al system near the Al3(Nb,Cr) + Cr(Al,Nb) eutectic region

    International Nuclear Information System (INIS)

    Souza, S.A.; Ferrandini, P.L.; Nunes, C.A.; Coelho, A.A.; Caram, R.

    2006-01-01

    The system Nb-Cr-Al was investigated in the region near the Al 3 (Nb,Cr) + Cr(Al,Nb) eutectic and the liquidus projection of that region was determined based on the microstructural characterization of arc melted alloys. The characterization utilized scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), differential thermal analysis (DTA) and X-ray diffraction (XRD). The results allowed one to determine three primary solidification liquidus surfaces ((Cr,Al) 2 Nb, Cr(Al,Nb) and Al 3 (Nb,Cr)), that are originated from the binary systems Cr-Nb, Cr-Al and Al-Nb. It is proposed the occurrence of the invariant reaction L + (Cr,Al) 2 Nb ↔ Al 3 (Nb,Cr) + Cr(Al,Nb) and of a point of minimum, which involves a three phase reaction, L ↔ Al 3 (Nb,Cr) + Cr(Al,Nb). All alloys studied showed formation of the Al 3 (Nb,Cr) + Cr(Al,Nb) eutectic as the last solidification step with Al(Nb)Cr 2 precipitating from Cr(Al,Nb)

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

    Energy Technology Data Exchange (ETDEWEB)

    Ma Xiaoguang [Key Laboratory of Liquid Structure and Heredity of Materials, Ministry of Education, Shandong University, Jinan 250061 (China); Liu Xiangfa [Key Laboratory of Liquid Structure and Heredity of Materials, Ministry of Education, Shandong University, Jinan 250061 (China)], E-mail: xfliu@sdu.edu.cn; Ding Haimin [Key Laboratory of Liquid Structure and Heredity of Materials, Ministry of Education, Shandong University, Jinan 250061 (China)

    2009-03-05

    Because flake-like TiAl{sub 3} 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 TiAl{sub 3} particles in Al-10Ti and TiC particles in Al-Ti-C can improve the nucleation rate of {alpha}-Al. It not only improves the grain refinement efficiency of Al-Ti-C master alloys, but also reduces the consumption.

  11. 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.

  12. Nanoporous Al sandwich foils using size effect of Al layer thickness during Cu/Al/Cu laminate rolling

    Science.gov (United States)

    Yu, Hailiang; Lu, Cheng; Tieu, A. Kiet; Li, Huijun; Godbole, Ajit; Kong, Charlie

    2018-06-01

    The roll bonding technique is one of the most widely used methods to produce metal laminate sheets. Such sheets offer interesting research opportunities for both scientists and engineers. In this paper, we report on an experimental investigation of the 'thickness effect' during laminate rolling for the first time. Using a four-high multifunction rolling mill, Cu/Al/Cu laminate sheets were fabricated with a range of thicknesses (16, 40, 70 and 130 μm) of the Al layer. The thickness of the Cu sheets was a constant 300 μm. After rolling, TEM images show good bonding quality between the Cu and Al layers. However, there are many nanoscale pores in the Al layer. The fraction of nanoscale pores in the Al layer increases with a reduction in the Al layer thickness. The finite element method was used to simulate the Cu/Al/Cu rolling process. The simulation results reveal the effect of the Al layer thickness on the deformation characteristics of the Cu/Al/Cu laminate. Finally, we propose that the size effect of the Al layer thickness during Cu/Al/Cu laminate rolling may offer a method to fabricate 'nanoporous' Al sandwich laminate foils. Such foils can be used in electromagnetic shielding of electrical devices and noisy shielding of building.

  13. Structural stability and electronic properties of AlCu3, AlCu2Zr in AlZr3: Stabilnost strukture in elektronske lastnosti AlCu3, AlCu2Zr in AlZr3:

    OpenAIRE

    Cheng, Rong; Wu, Xiao-Yu

    2013-01-01

    First-principles calculations were performed to study the alloying stability and electronic structure of the Al-based intermetallic compounds AlCusub3, AlCusub{2}Zr and AlZrsub3. The results show that the lattice parameters obtained after the full relaxation of the crystalline cells are consistent with the experimental data, and these intermetallics have a strong alloying ability and structural stability due to their negative formation energies and their cohesive energies. A further analysis ...

  14. /Cu-Al System

    Science.gov (United States)

    Kish, Orel; Froumin, Natalya; Aizenshtein, Michael; Frage, Nachum

    2014-05-01

    Wettability and interfacial interaction of the Ta2O5/Cu-Al system were studied. Pure Cu does not wet the Ta2O5 substrate, and improved spreading is achieved when relatively a high fraction of the active element (~40 at.% Al) was added. The Al2O3 and AlTaO4 phases were observed at the Ta2O5/Cu-Al interface. A thermodynamic evaluation allowed us to suggest that the lack of wetting bellow 40 at.% Al is due to the presence of a native oxide, which covers the drop. The conditions of the native oxide decomposition and the formation of the volatile Al2O suboxide strongly depend on the vacuum level during sessile drop experiments and the composition of the Cu-Al alloy. In our case, Al contents greater than 40% provides thermodynamic conditions for the formation of Al2O (as a result of Al reaction with Al2O3) and the drop spreading. It was suggested that the final contact angle in the Ta2O5/Cu-Al system (50°) is determined by Ta adsorption on the newly formed alumina interlayer.

  15. Metodologi Kitab Ma‘alim al-Tanzil Karya Al-Bagawiy

    Directory of Open Access Journals (Sweden)

    M. Rusydi Khalid

    2017-12-01

    This study aims to describe the metodology of Ma'a> lim al-tanzi>l book by al-Bagawi. The book is one of the books of exegesis written on the basis of hadith, which by the commentary scholars recognized avoided from heresy and weak hadith. The author of this book is Imam Abu Humaid Hussein bin Mas‘u>d al-Farra>’ Al-Bagawi al-Syafi‘i>, died in the year 510 H. This exegesis book combines the interpretation of the companions, tabi‘i>n, and tabi‘i> tabi‘i>n. Interpretation is broken down with easy, simple, and concise diction choices. The stoning of the interpretation of the salaf scholars without mentioning the sanad as already mentioned in the introduction to his book. This book was first printed in one edition with the exegesis book of Ibn Kas}i>r and al-kha>zin. This book interprets the Qur'an analytically from the beginning to the end of the surah by using the method of interpretation based on the hadith, namely by mentioning the arguments of the hadith sahih, the fatwa of the companions and the tabi‘i>n. The characteristic or purpose of this book is fiqh oriented, which tends to the Shafi‘i fiqh.   Abstrak Tulisan ini mendeskripsikan metode penafsiran dalam kitab Ma’a>lim al-tanzi>l karya al-bagawi. Kitab tafsir ini merupakan salah satu di antara kitab-kitab tafsir yang ditulis berdasarkan riwayat, yang oleh para ulama tafsir diakui terhindar dari bid’ah dan hadis dhaif (lemah. Penulis buku ini adalah Imam Abu Muhammad Husain bin Mas‘u>d al-Farra>‘ al-Bagawi al-Syafi‘i>, wafat pada tahun 510 H. Kitab ini adalah kitab pertengahan yang mengutip penafsiran para Sahabat, ta>bi‘i>n, dan tabi‘i ta>bi‘i>n. Penafsiran diuraikan dengan pilihan diksi yang mudah, sederhana, dan ringkas. Penukilan dari interpretasi ulama salaf tanpa menyebutkan sanad karena telah disebutkan dalam pendahuluan bukunya. Buku ini pertama kali dicetak dalam satu edisi dengan tafsir Ibn Kas\\i>r dan tafsir al-Kha>zin. Kitab ini menafsirkan al-Qur’an secara

  16. ALS Association

    Science.gov (United States)

    ... toward a world without ALS! Walk to Defeat ALS® Walk to Defeat ALS® draws people of all ... We need your help. I Will Advocate National ALS Registry The National ALS Registry is a congressionally ...

  17. AlN nanoparticle-reinforced nanocrystalline Al matrix composites: Fabrication and mechanical properties

    International Nuclear Information System (INIS)

    Liu, Y.Q.; Cong, H.T.; Wang, W.; Sun, C.H.; Cheng, H.M.

    2009-01-01

    To improve the specific strength and stiffness of Al-based composites, AlN/Al nanoparticles were in-situ synthesized by arc plasma evaporation of Al in nitrogen atmosphere and consolidated by hot-pressing to fabricate AlN nanoparticle-reinforced nanocrystalline Al composites (0-39 vol.% AlN). Microstructure characterization shows that AlN nanoparticles homogeneously distribute in the matrix of Al nanocrystalline, which forms atomically bonded interfaces of AlN/Al. The hardness and the elastic modulus of the nanocomposite have been improved dramatically, up to 3.48 GPa and 142 GPa, respectively. Such improvement is believed to result from the grain refinement strengthening and the interface strengthening (load transfer) between the Al matrix and AlN nanoparticles

  18. Comparison of one and two-neutron transfer near the Coulomb barrier for the 27Al(18O, 16O)29Al, 27Al(18O, 17O)28Al and 27Al(13C, 12C)28Al reactions

    International Nuclear Information System (INIS)

    Schiller, S.A.; Eck, J.S.

    1975-01-01

    Total reaction cross sections for the transfer reactions 27 Al( 18 O, 16 O) 29 Al, 27 Al( 18 O, 17 O) 28 Al and 27 Al( 13 C, 12 C) 28 Al are reported for center-of-mass energies between 13 and 20 MeV for 18 O projectiles and between 11 and 17.5 MeV for 13 C projectiles. The reaction products, 29 Al, and 28 Al, beta decay to 29 Si and 28 Si, respectively, and the subsequent γ decays of 29 Si and 28 Si were measured. Due to the relatively long beta decay half lives, data were taken in a beam-off mode, resulting in very clean spectra. Total cross sections were calculated and compared with a theoretical model for barrier penetration proposed by C.Y. Wong. Differences between 18 O induced one and two-neutron total transfer reaction cross sections are discussed. (orig.) [de

  19. Homocisteína como fator de risco para doenças cardiovasculares

    Directory of Open Access Journals (Sweden)

    Sthefano Atique Gabriel

    2007-05-01

    Full Text Available Elevadas concentrações plasmáticas de homocisteína têm sido identificadas como um fator de risco independente para aterosclerose cerebral, coronariana e periférica. Os efeitos danosos da homocisteína sérica são fruto de suas características aterogênicas e trombogênicas. O tratamento mais eficaz para hiperhocisteinemia consiste na redução da homocisteína plasmática, através da fortificação alimentar com suplementos vitamínicos, ricos em vitamina B6, vitamina B12 e, principalmente, acido fólico. A dose recomendada é de 400 microgramos de folato por dia, sendo esta medida uma poderosa redutora da morbidade e mortalidade cardiovascular, além de prevenir possíveis defeitos de fechamento do tubo neural.

  20. Al-matrix composite materials reinforced by Al-Cu-Fe particles

    International Nuclear Information System (INIS)

    Bonneville, J; Laplanche, G; Joulain, A; Gauthier-Brunet, V; Dubois, S

    2010-01-01

    Al-matrix material composites were produced using hot isostatic pressing technique, starting with pure Al and icosahedral (i) Al-Cu-Fe powders. Depending on the processing temperature, the final reinforcement particles are either still of the initial i-phase or transformed into the tetragonal ω-Al0 0.70 Cu 0.20 Fe 0.10 crystalline phase. Compression tests performed in the temperature range 293K - 823K on the two types of composite, i.e. Al/i and Al/ω, indicate that the flow stress of both composites is strongly temperature dependent and exhibit distinct regimes with increasing temperature. Differences exist between the two composites, in particular in yield stress values. In the low temperature regime (T ≤ 570K), the yield stress of the Al/ω composite is nearly 75% higher than that of the Al/i composite, while for T > 570K both composites exhibit similar yield stress values. The results are interpreted in terms of load transfer contribution between the matrix and the reinforcement particles and elementary dislocation mechanisms in the Al matrix.

  1. Piezo-tunnel effect in Al/Al2O3/Al junctions elaborated by atomic layer deposition

    Science.gov (United States)

    Rafael, R.; Puyoo, E.; Malhaire, C.

    2017-11-01

    In this work, the electrical transport in Al/Al2O3/Al junctions under mechanical stress is investigated in the perspective to use them as strain sensors. The metal/insulator/metal junctions are elaborated with a low temperature process (≤200 °C) fully compatible with CMOS back-end-of-line. The conduction mechanism in the structure is found to be Fowler-Nordheim tunneling, and efforts are made to extract the relevant physical parameters. Gauge factors up to -32.5 were found in the fabricated devices under tensile stress. Finally, theoretical mechanical considerations give strong evidence that strain sensitivity in Al/Al2O3/Al structures originates not only from geometrical deformations but also from the variation of interface barrier height and/or effective electronic mass in the tunneling oxide layer.

  2. 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.

  3. 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. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Energy alternative for the use of organic waste (swine feces) in the state of Tabasco; Alternativa energetica para el aprovechamiento de los desechos organicos (excretas de ganado porcino) en el estado de Tabasco

    Energy Technology Data Exchange (ETDEWEB)

    Ramon Garcia, E.; Angles Falconi, S.I.; Vazquez Magana, L.R.; Tun Perez, A.C. [Instituto Tecnologico de Villahermosa, Villahermosa, Tabasco (Mexico)]. Email: bioleliza_ramgar@hotmail.com; sergio_falcorp@hotmail.com

    2009-09-15

    Biogas is obtained from decomposing organic material due to the action of four types of bacteria, in the absence of oxygen: hydrolytic, producers of moncarbonate compounds and acidogenics, producing organic fatty acids and other polycarbonate compounds; acetogenic, producers of hydrogen and CO{sub 2}; homoacetogenic, that can convert a considerable amount of multicarbonate or monocarbonate compounds into acetic acid and; metanogenic, producers of methane gas, the principal component of biogas. To design and build the pilot equipment proposed for this research, a 20-liter container was used with 10 kg of swine feces with identical volumes of inoculates. The aerobic fermentation process was immediate begun, followed by the anaerobic process; metabolic reactions were conducted. A total of 0.119 m3 of biogas was obtained from the anaerobic fermentation of 10 kg of swine feces, 60% (0.0714 m{sup 3}) of which was methane gas and the remaining 40%(0.0476 m{sup 3}) hydrogen sulfide (HS). During this investigation, it was concluded that obtaining this by-product (methane biogas), which can be used as a biofuel, provides an economically and ecologically sustainable alternative that reduces organic discharges (swine feces) into rivers and reduces the energy expenditures of swine farms. Because of the high generation of RSM, the creation of a biogas production plant in Tabasco is proposed. [Spanish] El biogas se obtiene al descomponerse la materia organica debido a la accion de cuatro tipos de bacterias, en ausencia de oxigeno: las hidroliticas, que producen compuestos monocarbonados, las acidogenicas producen acidos grasos organicos y otros compuestos policarbonados; las acetogenicas productoras de Hidrogeno y CO{sub 2}; las homoacetogenicas, que pueden convertir una cantidad considerable de compuestos multicarbonados o monocarbonados en acido acetico; y las metanogenicas, productoras del gas metano, principal componente del biogas. Para el diseno y construccion del equipo

  5. Radiation detection with Nb/Al-AlOx/Al/Nb superconducting tunnel junctions

    International Nuclear Information System (INIS)

    Matsumura, Atsuki; Takahashi, Toru; Kurakado, Masahiko

    1992-01-01

    Superconductor radiation detectors have the possibility of 20-30 times better energy resolution than that of a high resolution Si detector. We fabricated Nb/Al-AlOx/Al/Nb superconducting tunnel junctions with low leakage current. X rays were detected with large area junctions of 178x178 μm 2 . High energy resolution of 160 eV for 5.9 keV was obtained. We also fabricated series connected junctions which covers a rather large area of 4x4 mm 2 . α particles injected into the rear substrate were detected using nonthermal phonons induced by the radiations in the substrate. (author)

  6. ALS-Plus Syndrome: Non-Pyramidal Features in a Large ALS Cohort

    Science.gov (United States)

    McCluskey, Leo; Vandriel, Shannon; Elman, Lauren; Van Deerlin, Vivianna M.; Powers, John; Boller, Ashley; Wood, Elisabeth McCarty; Woo, John; McMillan, Corey T.; Rascovsky, Katya; Grossman, Murray

    2014-01-01

    Objective Autopsy studies show widespread pathology in amyotrophic lateral sclerosis (ALS), but clinical surveys of multisystem disease in ALS are rare. We investigated ALS-Plus syndrome, an understudied group of patients with clinical features extending beyond pyramidal and neuromuscular systems with or without cognitive/behavioral deficits. Methods In a large, consecutively-ascertained cohort of 550 patients with ALS, we documented atypical clinical manifestations. Genetic screening for C9orf72 hexanucleotide expansions was performed in 343 patients, and SOD1, TARDBP, and VCP were tested in the subgroup of patients with a family history of ALS. Gray matter and white matter imaging was available in a subgroup of 30 patients. Results Seventy-five (13.6%) patients were identified with ALS-Plus syndrome. We found disorders of ocular motility, cerebellar, extrapyramidal and autonomic functioning. Relative to those without ALS-Plus, cognitive impairment (8.0% vs 2.9%, p=0.029), bulbar-onset (49.3% vs 23.2%, pALS-Plus. Survival was significantly shorter in ALS-Plus (29.66 months vs 42.50 months, p=0.02), regardless of bulbar-onset or mutation status. Imaging revealed significantly greater cerebellar and cerebral disease in ALS-Plus compared to those without ALS-Plus. Conclusions ALS-Plus syndrome is not uncommon, and the presence of these atypical features is consistent with neuropathological observations that ALS is a multisystem disorder. ALS-Plus syndrome is associated with increased risk for poor survival and the presence of a pathogenic mutation. PMID:25086858

  7. Tailoring ultrafine grained and dispersion-strengthened Ti 2 AlC/TiAl ...

    Indian Academy of Sciences (India)

    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 ∘ 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.

  8. Assessing behavioural changes in ALS: cross-validation of ALS-specific measures.

    Science.gov (United States)

    Pinto-Grau, Marta; Costello, Emmet; O'Connor, Sarah; Elamin, Marwa; Burke, Tom; Heverin, Mark; Pender, Niall; Hardiman, Orla

    2017-07-01

    The Beaumont Behavioural Inventory (BBI) is a behavioural proxy report for the assessment of behavioural changes in ALS. This tool has been validated against the FrSBe, a non-ALS-specific behavioural assessment, and further comparison of the BBI against a disease-specific tool was considered. This study cross-validates the BBI against the ALS-FTD-Q. Sixty ALS patients, 8% also meeting criteria for FTD, were recruited. All patients were evaluated using the BBI and the ALS-FTD-Q, completed by a carer. Correlational analysis was performed to assess construct validity. Precision, sensitivity, specificity, and overall accuracy of the BBI when compared to the ALS-FTD-Q, were obtained. The mean score of the whole sample on the BBI was 11.45 ± 13.06. ALS-FTD patients scored significantly higher than non-demented ALS patients (31.6 ± 14.64, 9.62 ± 11.38; p ALS-FTD-Q was observed (r = 0.807, p ALS-FTD-Q. Good construct validity has been further confirmed when the BBI is compared to an ALS-specific tool. Furthermore, the BBI is a more comprehensive behavioural assessment for ALS, as it measures the whole behavioural spectrum in this condition.

  9. Vitamina B12, Acido Fólico y Función Mental en Adultos Mayores

    OpenAIRE

    Meertens-R, Lesbia; Solano-R, Liseti

    2005-01-01

    Los adultos mayores constituyen un grupo de población vulnerable a cuadros de deficiencias de nutrientes específicos como la vitamina B12 y el ácido fólico, íntimamente ligados al deterioro de las funciones mentales, en especial, del área cognitiva. El objetivo de este estudio fue determinar indicadores del estado de vitamina B12 y ácido fólico y asociarlos a la evaluación de la función mental de 53 adultos mayores de 60 años de edad, residenciados en un hogar geriátrico. Se evaluó consumo di...

  10. Plastic deformation of Al13Fe4 particles in Al-Al13Fe4 by high-speed compression

    International Nuclear Information System (INIS)

    Yoneyama, N.; Mizoguchi, K.; Kumai, S.; Sato, A.; Kiritani, M.

    2003-01-01

    Spray-formed Al-Fe alloys having undergone high-speed deformation were examined under a high-voltage electron microscope. Two types of specimens were examined; one containing fine Al 13 Fe 4 particles, and the other containing large particles. In the former specimen, deformation is found to proceed in three patterns, depending on specimen thickness and strain rate: (1) without deformation of the Al 13 Fe 4 ; (2) breaking of the Al 13 Fe 4 ; or (3) melting of the Al 13 Fe 4 . Local melting is found to alter some of the Al 13 Fe 4 particles, to impart five-fold symmetry in diffraction or an amorphous structure. In the latter specimen, introduction of glide dislocations enabled us to determine a shear system in the mc102 monoclinic c2/m crystal of Al 13 Fe 4 . On the bases of these observations, the mechanism of high-speed deformation is discussed while taking into account the highly stressed and/or heated states of Al 13 Fe 4 embedded in Al matrix

  11. Synthesis and characterization of pillared bentonite with Al, AL/Fe and impregnated with Pd; Sintese e caracterizacao de bentonitas pilarizadas com Al, AL/Fe e impregnadas com Pd

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Marcus Vinicius Costa; Pizarro, Alejandro Herrero; Molina, Carmen Belen, E-mail: marcus.ufpa@yahoo.com.br [Universidade Federal do Para (UFPA), Belem, PA (Brazil). Instituto de Tecnologia. Faculdade de Engenharia Quimica; Seccion de Ingenieria Quimica, Facultad de Ciencias, Universidad Autonoma de Madri (Spain)

    2017-10-01

    In this work, a north american bentonite was pillared with Al and Al/Fe, creating the Al-PILC and Al-Fe-PILC, respectively. Then the Pd was impregnated in the materials, generating Pd-Al-PILC and Pd-Al-Fe-PILC, respectively. The samples were characterized by X-ray diffraction, differential thermal analysis and thermogravimetric and N{sub 2} adsorption at 77 K to determine the specific surface area by BET method (Brunauer - Emmett - Teller). There was an increase in the basal spacing of bentonite from 12.4Å in the original sample to 17.81Å in the Al-Fe-PILC, 17.20Å in Pd-Al-PILC and 17.05Å in the Pd-Al-Fe-PILC. The specific surface area increased from 19.05m{sup 2}/g in the original sample to 173.49m{sup 2}/g in Al-Fe-PILC, 101.31m{sup 2}/g to Pd-Al-PILC and 92m{sup 2}/g in Pd-Al-Fe-PILC. The pillaring process was successful and the synthesized materials have great potential for use as catalysts. (author)

  12. Electrodeposition of Al from a 1-butylpyrrolidine-AlCl3 ionic liquid

    Directory of Open Access Journals (Sweden)

    Giridhar Pulletikurthi

    2015-12-01

    Full Text Available The addition of 1-butylpyrrolidine to AlCl3 results in the formation of an electrolyte that is suited to Al deposition. The feasibility of electrodepositing Al from the synthesized electrolyte was investigated. Several compositions of AlCl3 and 1-butylpyrrolidine were prepared for this purpose. These mixtures show a different phase behavior at various compositions of AlCl3 and 1-butylpyrrolidine. IR, Raman and NMR spectroscopy were employed to characterize the synthesized liquids. Among the prepared compositions, 1:1.2 mol ratio of 1-butylpyrrolidine:AlCl3 and the upper phase of 1:1.3 mol ratio of 1-butylpyrrolidine:AlCl3 were found to be suitable for Al electrodeposition at room temperature (RT. Uniform and thick (~µm thick layers of Al were obtained on copper at RT. Al deposition occured from the cationic species of AlCl3−xLy+ (where x≤2, y=1–2, and L=1-butylpyrrolidine in this electrolyte. This behavior is contrary to the well investigated classic AlCl3 based ionic liquids, where the deposition of Al occurs mainly from anionic Al2Cl7− ions.

  13. Orientation of Al3Ti platelets in Al-Al3Ti functionally graded material manufactured by centrifugal method

    International Nuclear Information System (INIS)

    Watanabe, Y.; Fukui, Y.

    1997-01-01

    Al-Al 3 Ti functionally graded materials (FGMs) were manufactured by the centrifugal method with a commercial ingot of Al-5 mass% Ti master alloy. The alloy was melted at a liquid/solid coexisting temperature, at which Al 3 Ti remains as a solid, and then it was cast into a thick-walled ring. It was found that the Al-Al 3 Ti functionally graded material can be successfully fabricated by the centrifugal method. It was also found that the volume fraction of the Al 3 Ti can be increased by repetition of the centrifugal method. Since the shape of Al 3 Ti particles in a commercial alloy ingot is that of a platelet, the Al 3 Ti particles are arranged with their platelet planes nearly perpendicular to the radial direction. The orientation effects become stronger when the G number becomes larger. Although the final centrifugal casting was conducted under a very large centrifugal force for the specimen cast three times, the orientation effects were weaker than those in the specimen cast one time. From these observations, it is concluded that the origin of orientation of Al 3 Ti platelets can be attributed to the angular velocity gradient of the melt along the radial direction produced by the difference in the viscosity. (orig.)

  14. In situ synthesis of Ti{sub 2}AlC–Al{sub 2}O{sub 3}/TiAl composite by vacuum sintering mechanically alloyed TiAl powder coated with CNTs

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jian [Department of Materials Science and Engineering of Tianjin University, Tianjin Key Laboratory of Composite and Functional Materials, Tianjin 300072 (China); Zhao, Naiqin, E-mail: nqzhao@tju.edu.cn [State Key Laboratory of Hydraulic Engineering Simulation and Safety, Tianjin (China); Department of Materials Science and Engineering of Tianjin University, Tianjin Key Laboratory of Composite and Functional Materials, Tianjin 300072 (China); Nash, Philip [Thermal Processing Technology Center, Illinois Institute of Technology, IL (United States); Liu, Enzuo; He, Chunnian; Shi, Chunsheng; Li, Jiajun [Department of Materials Science and Engineering of Tianjin University, Tianjin Key Laboratory of Composite and Functional Materials, Tianjin 300072 (China)

    2013-11-25

    Highlights: •Using zwitterionic surfactant to enhance the dispersion of the CNTs on the powder surface. •CNTs as carbon source decreased the formation temperature of Ti{sub 2}AlC. •Al{sub 2}O{sub 3} was generated in situ from the oxygen atoms introduced in the drying procedure. •Nanosized Ti{sub 3}Al was precipitated at 1250 °C and distribute in the TiAl matrix homogeneously. •Ti{sub 2}AlC–Al{sub 2}O{sub 3}/TiAl composite was synthesized in situ by sintering pre-alloy Ti–Al coated with CNTs. -- Abstract: Bulk Ti{sub 2}AlC–Al{sub 2}O{sub 3}/TiAl composites were in situ synthesized by vacuum sintering mechanically alloyed Ti–50 at.% Al powders coated with carbon nanotubes (CNTs). The pre-alloyed Ti–50 at.% Al powder was obtained by ball milling Ti and Al powders. The multi-walled carbon nanotubes as the carbon resource were covered on the surface of the pre-alloyed powders by immersing them into a water solution containing the CNTs. A zwitterionic surfactant was used to enhance the dispersion of the CNTs on the powder surface. The samples were cold pressed and sintered in vacuum at temperatures from 950 to 1250 °C, respectively. The results show that the reaction of forming Ti{sub 2}AlC can be achieved below 950 °C, which is 150 °C lower than in the Ti–Al–TiC system and 250 °C lower than for the Ti–Al–C system due to the addition of CNTs. Additionally, the reinforcement of Al{sub 2}O{sub 3} particles was introduced in situ in Ti{sub 2}AlC/TiAl by the drying process and subsequent sintering of the composite powders. Dense Ti{sub 2}AlC–Al{sub 2}O{sub 3}/TiAl composites were obtained by sintering at 1250 °C and exhibited a homogeneous distribution of Ti{sub 2}AlC, Al{sub 2}O{sub 3} and precipitated Ti{sub 3}Al particles and a resulting high hardness.

  15. 27Al NMR studies of NpPd5Al2

    International Nuclear Information System (INIS)

    Chudo, H.; Sakai, H.; Tokunaga, Y.; Kambe, S.; Aoki, D.; Homma, Y.; Shiokawa, Y.; Haga, Y.; Ikeda, S.; Matsuda, T.D.; Onuki, Y.; Yasuoka, H.

    2009-01-01

    We present 27 Al NMR studies for a single crystal of the Np-based superconductor NpPd 5 Al 2 (T c =4.9K). We have observed a five-line 27 Al NMR spectrum with a center line and four satellite lines separated by first-order nuclear quadrupole splittings. The Knight shift clearly drops below T c . The temperature dependence of the 27 Al nuclear spin-lattice relaxation rate shows no coherence peak below T c , indicating that NpPd 5 Al 2 is an unconventional superconductor with an anisotropic gap. The analysis of the present NMR data provides evidence for strong-coupling d-wave superconductivity in NpPd 5 Al 2 .

  16. Magnetic tunnel junctions with AlN and AlNxOy barriers

    International Nuclear Information System (INIS)

    Schwickert, M. M.; Childress, J. R.; Fontana, R. E.; Kellock, A. J.; Rice, P. M.; Ho, M. K.; Thompson, T. J.; Gurney, B. A.

    2001-01-01

    Nonoxide tunnel barriers such as AlN are of interest for magnetic tunnel junctions to avoid the oxidation of the magnetic electrodes. We have investigated the fabrication and properties of thin AlN-based barriers for use in low resistance magnetic tunnel junctions. Electronic, magnetic and structural data of tunnel valves of the form Ta (100 Aa)/PtMn (300 Aa)/CoFe 20 (20 Aa - 25 Aa)/barrier/CoFe 20 (10 - 20 Aa)/NiFe 16 (35 - 40 Aa)/Ta (100 Aa) are presented, where the barrier consists of AlN, AlN x O y or AlN/AlO x with total thicknesses between 8 and 15 Aa. The tunnel junctions were sputter deposited and then lithographically patterned down to 2 x 2μm 2 devices. AlN was deposited by reactive sputtering from an Al target with 20% - 35% N 2 in the Ar sputter gas at room temperature, resulting in stoichiometric growth of AlN x (x=0.50±0.05), as determined by RBS. TEM analysis shows that the as-deposited AlN barrier is crystalline. For AlN barriers and AlN followed by natural O 2 oxidation, we obtain tunnel magnetoresistance >10% with specific junction resistance R j down to 60Ωμm 2 . [copyright] 2001 American Institute of Physics

  17. A study of the Al-rich part of the Al-Re alloy system

    International Nuclear Information System (INIS)

    Balanetskyy, S.; Grushko, B.

    2008-01-01

    The Al-rich part of the Al-Re phase diagram was reinvestigated by scanning and transmission electron microscopy, powder X-ray diffraction and differential thermal analysis. The earlier reported Al 12 Re, Al 6 Re, and Al 11 Re 4 phases were confirmed. Close to the Al 4 Re composition a high-temperature h-Al 4 Re and a low-temperature l-Al 4 Re phase were found to be formed at slightly different compositions. Both exhibited compositional ranges. A new phase was revealed close to the Al 3 Re composition. The Al 11 Re 4 phase is formed congruently at 1650 deg. C, Al 3 Re peritectically at 1610 deg. C, h-Al 4 Re peritectically at 1410 deg. C, l-Al 4 Re peritectically at ∼1000 deg. C, Al 6 Re peritectically at 813 deg. C and Al 12 Re peritectically at 746 deg. C. Finally, the Al 12 Re-(Al) eutectic is formed at 658 deg. C. The Al 3 Re and h-Al 4 Re are decomposed by eutectoid reactions at ∼946 and 833 deg., respectively. The structure of the h-Al 4 Re phase has not yet been clarified, but it is distinctly different from the Al 4 W phase suggested earlier. The structure of l-Al 4 Re was confirmed. The Al 3 Re phase was found to have a monoclinic structure with a = 0.5180(4) nm, b = 3.97641(9) nm, c = 0.4955(3) nm and β = 99.55(7) o

  18. Abu al-Layth al-Libi

    Science.gov (United States)

    2015-02-01

    success. As an Arab participant acknowledged very early on, “the situation was really harsh. All the brothers were tired,” as they lacked food and... glorious battles that occurred during the early Islamic period.133 He stressed the importance of the battlefield as the path to achieve honor and dignity...diaspora in Waziristan. In the words of Walid Othmani, a French jihadi trained by al-Qa`ida in Waziristan in 2008, “[Al-Libi] was someone well-known and

  19. Determination of the load state of lead-acid batteries using neural networks; Determinacion del estado de carga de baterias plomo-acido utilizando redes neuronales

    Energy Technology Data Exchange (ETDEWEB)

    Cristin V, Miguel A; Ortega S, Cesar A [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2005-07-01

    The charge of lead-acid batteries (LAB), as in any other type of batteries, consists of replacing the energy consumed during the discharge. Nevertheless, as no physical or chemical process is good enough to totality recharge a battery, it is necessary to supply to it more than the 100% of the energy demanded during its discharge. A critical factor to make a suitable load control of the batteries is to determine its own state of load. That is to say, to have an efficient load control, it is necessary to count on means that allow to accurately determining the residual capacity of the battery to deliver load. This one is the one of the aspects of greater interest in the research centers around world. For this reason, in this work it was pretended to develop a calculation algorithm of the state of load of batteries based on a fuzzy-neural network that could calculate the state of load without using the battery current as an input. This is because one of the main problems for the designers of battery load controllers is the correct supervision of the current that circulates around the system in all the rank of operation of the same one because the sensors do not have a linear behavior. [Spanish] La recarga de baterias plomo-acido (BPA), como cualquier otro tipo de baterias, consiste en reponer la energia consumida durante la descarga. Sin embargo, como ningun proceso fisico o quimico es lo bastante eficiente para recargar a totalidad una bateria, es necesario suministrarle mas del 100% de la energia demandada durante su descarga. Un factor critico para realizar un adecuado control de carga de las baterias, es determinar su propio estado de carga. Es decir, para tener un control de carga eficiente, es necesario contar con un medio que permita determinar con precision la capacidad remanente de la bateria para entregar carga. Este es uno de los aspectos de mayor interes en los centros de investigacion alrededor el mundo. Por tal razon, en este trabajo se propuso

  20. SAP-like ultrafine-grained Al composites dispersion strengthened with nanometric AlN

    International Nuclear Information System (INIS)

    Balog, M.; Krizik, P.; Yan, M.; Simancik, F.; Schaffer, G.B.; Qian, M.

    2013-01-01

    This paper reports the development of novel Sinter-Aluminum-Pulver (SAP)-like Al–AlN nanocomposites via replacing the native Al 2 O 3 thin films on fine Al powder with a large volume fraction of in situ formed nanometric AlN dispersoids. Fine gas-atomized Al powder (d 50 =1.3 µm) compacts were first partially nitrided at 590 °C in flowing nitrogen, controlled by a small addition of Sn (0.3–0.4 wt%), and subsequently consolidated by hot direct extrusion. The resulting Al–AlN composites consisted of submicrometric Al grains reinforced with nanometric AlN dispersoids together with some nanometric Al 2 O 3 dispersoids. An Al–13 vol% AlN nanocomposite fabricated this way achieved exceptional ultimate tensile strength of 227 MPa, yield strength of 195 MPa and Young's modulus of 66 GPa at 300 °C, superior to typical SAP materials and coarse grained Al–AlN composites. In addition, the Al–13 vol% AlN nanocomposite exhibited good thermal stability up to 500 °C. The strengthening mechanism is discussed

  1. Analisis Kecenderungan Manhaj Akidah Shaykh Shams al-Din al-Sumatera’i

    Directory of Open Access Journals (Sweden)

    MOHD HAIDHAR KAMARZAMAN

    2016-12-01

    Full Text Available Shaykh Shams al-Din al-Sumatera'i is a very great and respected scholar during 16th and 17th century of Acheh. His knowledge in various fields recognized by local and international scholars. He had been a Qadi Malik al-’Adil, a religious leader, who became a referred by communities and country during the reign of the three Sultans of Aceh. He has authored nearly 40 pieces of books related to the theology and sufism. This study focuses on the methods used by Shaykh Shams al-Din al-Sumatera'i in his theological writings. This study found that Shaykh Shams al-Din al-Sumatera'i had used six methods in the such writings.

  2. Ultrasonic spot welding of Al/Mg/Al tri-layered clad sheets

    International Nuclear Information System (INIS)

    Macwan, A.; Patel, V.K.; Jiang, X.Q.; Li, C.; Bhole, S.D.; Chen, D.L.

    2014-01-01

    Highlights: • The optimal welding condition is achieved at 100 J and 0.1 s. • Failure load first increases and then decreases with increasing welding energy. • The highest failure load after welding is close to that of the clad sheets. • At low energy levels failure occurs in the mode of interfacial failure. • At high energy levels failure takes place at the edge of nugget region. - Abstract: Solid-state ultrasonic spot welding (USW) was used to join Al/Mg/Al tri-layered clad sheets, aiming at exploring weldability and identifying failure mode in relation to the welding energy. It was observed that the application of a low welding energy of 100 J was able to achieve the optimal welding condition during USW at a very short welding time of 0.1 s for the tri-layered clad sheets. The optimal lap shear failure load obtained was equivalent to that of the as-received Al/Mg/Al tri-layered clad sheets. With increasing welding energy, the lap shear failure load initially increased and then decreased after reaching a maximum value. At a welding energy of 25 J, failure occurred in the mode of interfacial failure along the center Al/Al weld interface due to insufficient bonding. At a welding energy of 50 J, 75 J and 100 J, failure was also characterized by the interfacial failure mode, but it occurred along the Al/Mg clad interface rather than the center Al/Al weld interface, suggesting stronger bonding of the Al/Al weld interface than that of the Al/Mg clad interface. The overall weld strength of the Al/Mg/Al tri-layered clad sheets was thus governed by the Al/Mg clad interface strength. At a welding energy of 125 J and 150 J, thinning of weld nugget and extensive deformation at the edge of welding tip caused failure at the edge of nugget region, leading to a lower lap shear failure load

  3. KITAB AL-SANĪ AL-MAṬĀLIB: INTERKONEKSI NAHWU DAN TASAWUF

    Directory of Open Access Journals (Sweden)

    Zakiyah Zakiyah

    2012-12-01

    Tulisan ini mereview buku yang berjudul al-Sanī al-Maṭālib yang ditulis oleh Kiai Nur Iman Mlangi Yogyakarta. Buku ini ditulis dalam bahasa Arab yang me­ngandung interkoneksi antara ilmu Nahwu (tata bahasa Arab dengan mis­tisis­me. Buku ini sangat menarik karena kenyataan bahwa kedua pengetahuan tersebut memiliki aturan sendiri-sendiri. Selain itu, sangat sedikit penulis yang menulis dengan gaya seperti itu. Salah satunya adalah Syaikh Abdul Qadir bin Ahmad al-Kuhany dengan karyanya yang berjudul Manniyat al-Fāqir al-Munjarid wa Sayrat al-Murīd al-Mutafarrid. Buku al-Saniy al-Muthalib diduga telah ditulis pada akhir abad ke-18 atau awal abad ke-19, menurut periode kehidupan Kiai Nur Iman yaitu sekitar pertengahan abad ke-18. Aturan Nahwu dalam buku ini dijelaskan secara teosofi yang dimulai dengan penjelasan mengenai tauhid (keesaan Tuhan sebagai kajian dasar bagi orang Islam, yang diikuti dengan makna dari masing-masing aturan bahasa Arab dalam aspek mistiknya.

  4. Rekonstruksi Konsep Ijtihad: Studi Pemikiran Ben’umar tentang al-Ijtihad fi al-Waqi’

    Directory of Open Access Journals (Sweden)

    Duski Ibrahim

    2015-10-01

    Full Text Available This paper is the result of a research that evaluating the reconstruction the concept of ijtihad, by discuss the idea of al-Ijtihad Ben'umar fi al-waqi’. This paper concludes that Al-Ijtihad fi al-waqi’ is actually a form of collective ijtihad (al ijtihad al-jama'i, by gathering the experts of shari'ah law (fuqaha` ash-shar'i and experts Researchers and scientists (khubara` al-'ashr. Because experts know the nash purposes, while researchers and scientists (al-khubara` know the reality (al-waqi’, the effects in the future (ma'alat = future effect and challenges (tahaddiyat. The idea of formulating the concept of al-ijtihad fi al-waqi’ emerged based on a premise that ijtihad is a creation of experts to implement Islamic law in society. Therefore, the concept of ijtihad experienced a significant development, start from using the nash from the language aspects, continue to the using of logic. At the moment when the situation people are increasingly develop, then the creation of ijtihad become a necessary to developed, for example in the form of al-ijtihad fi al-waqi’ . About the source of the formation of the concept of al -ijtihad fi al-waqi’ comes from theory about the functions of nash, al-manath theory in Islamic law, and supported by the theory of al-mashlalah al-mursalah.

  5. Study of the 26Al(n,p)26Mg and 26Al(n,α)23Na reactions using the 27Al(p,p')27Al inelastic scattering reaction

    International Nuclear Information System (INIS)

    Benamara, S; De Séréville, N; Hammache, F; Stefan, I; Roussel, P; Ancelin, S; Assié, M; Guillot, J; Le Crom, B; Lefebvre, L; Adsley, P; Laird, A M; Barton, C; Diget, C; Fox, S; Coc, A; Deloncle, I; Hamadache, C; Kiener, J; Lefebfre-Schuhl, A

    2016-01-01

    26 Al was the first cosmic radioactivity ever detected in the galaxy as well as one of the first extinct radioactivity observed in refractory phases of meteorites. Its nucleosynthesis in massive stars is still uncertain mainly due to the lack of nuclear information concerning the 26 Al(n,p) 26 Mg and 26 Al(n,α) 23 Na reactions. We report on a single and coincidence measurement of the 27 Al(p,p') 27 Al(p) 26 Mg and 27 Al(p,p') 27 Al(α) 23 Na reactions performed at the Orsay TANDEM facility aiming at the spectroscopy study of 27 Al above the neutron threshold. Fourteen states are observed for the first time within 350 keV above the 26 Al+n threshold. (paper)

  6. AlN/Al dual protective coatings on NdFeB by DC magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Li Jinlong; Mao Shoudong; Sun Kefei [Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Li Xiaomin [Shanghai Institute of Ceramics Chinese Academy of Sciences, Shanghai 200050 (China); Song Zhenlun [Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China)], E-mail: songzhenlun@nimte.ac.cn

    2009-11-15

    AlN/Al dual protective coatings were prepared on NdFeB by DC magnetron sputtering in a home-made industrial apparatus. Comparing with Al coating, AlN/Al coatings have a denser structure of an outmost AlN amorphous layer following an inner Al columnar crystal layer. The coatings and NdFeB substrate combine well, and moreover, there is occurrence of metallurgy bonding in the interface layer. Both Al and AlN/Al coatings have a good protective ability to NdFeB. Especially, the corrosion resistance of AlN/Al coated NdFeB is improved largely. AlN/Al and Al protective coatings not only do not deteriorate the magnetic properties of NdFeB, but contribute to their slight increase.

  7. AlN/Al dual protective coatings on NdFeB by DC magnetron sputtering

    International Nuclear Information System (INIS)

    Li Jinlong; Mao Shoudong; Sun Kefei; Li Xiaomin; Song Zhenlun

    2009-01-01

    AlN/Al dual protective coatings were prepared on NdFeB by DC magnetron sputtering in a home-made industrial apparatus. Comparing with Al coating, AlN/Al coatings have a denser structure of an outmost AlN amorphous layer following an inner Al columnar crystal layer. The coatings and NdFeB substrate combine well, and moreover, there is occurrence of metallurgy bonding in the interface layer. Both Al and AlN/Al coatings have a good protective ability to NdFeB. Especially, the corrosion resistance of AlN/Al coated NdFeB is improved largely. AlN/Al and Al protective coatings not only do not deteriorate the magnetic properties of NdFeB, but contribute to their slight increase.

  8. 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.

  9. AlGaN nanocolumns and AlGaN/GaN/AlGaN nanostructures grown by molecular beam epitaxy

    Energy Technology Data Exchange (ETDEWEB)

    Ristic, J.; Sanchez-Garcia, M.A.; Ulloa, J.M.; Calleja, E. [Departamento de Ingenieria Electronica, ETSI Telecomunicacion, Universidad Politecnica de Madrid, Ciudad Universitaria, 28040 Madrid (Spain); Sanchez-Paramo, J.; Calleja, J.M. [Departamento de Fisica de Materiales, Universidad Autonoma de Madrid, Cantoblanco, 28049 Madrid (Spain); Jahn, U.; Trampert, A.; Ploog, K.H. [Paul-Drude-Institut fuer Festkoerperelektronik, Hausvogteiplatz 5-7, 10117 Berlin (Germany)

    2002-12-01

    This work reports on the characterization of hexagonal, single crystal AlGaN nanocolumns with diameters in the range of 30 to 100 nm grown by molecular beam epitaxy on Si(111) substrates. The change of the flux ratio between the Al and the total III-element controls the alloy composition. The Al composition trend versus the Al flux is consistent both with the E{sub 2} phonon energy values measured by inelastic light scattering and the luminescence emission peaks position. High quality low dimensional AlGaN/GaN/AlGaN heterostructures with five GaN quantum discs, 2 and 4 nm thick, embedded into the AlGaN columns, were designed in order to study the quantum confinement effects. (Abstract Copyright [2002], Wiley Periodicals, Inc.)

  10. KONSEPSI AL-QURAN DAN AL-HADITS TENTANG OPERASIONAL BANK SYARIAH

    Directory of Open Access Journals (Sweden)

    Muhammad Ardy Zaini

    2015-01-01

    Full Text Available Islam hadir dengan beberapa tujuan, diantaranya adalah terciptanya khoirul ummah dan rahmatan lil’alamin dengan al-Qur’an dan al-Hadits sebagai penuntun umat Islam demi tercapainya tujuan tersebut. Sebagai pedoman hidup, al-Qur’an dan al-Hadits memberikan berbagai petunjuk tentang keteraturan dan permasalahan hidup, termasuk didalamnya mengenai perbankan yang telah memenuhi hampir separuh sisi-sisi kehidupan manusia. Untuk memaksimal ajaran syariah secara kaffah, maka nilai-nilai yang terdapat dalam al-Quran harus mampu diturunkan pada tataran praktis. Salah satu usaha dan langkah dalam rangka menemukan formula perbankan masa depan, al-Quran dan Hadits memiliki konsepsi dalam kegiatan operasional Bank Syariah. Hal ini dilakukan untuk membentuk sikap mental atau watak yang terjabarkan dalam pola berpikir, cara berbicara, dan etika bertingkah laku, sebagai ekspresi jiwa dari manusia yang beriman dan bertakwa kepada Allah Swt. Agar umat Islam mampu menjadi umat yang unggul (khayr ummah.

  11. 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.

  12. The formation of AlB2 in an Al-B master alloy

    International Nuclear Information System (INIS)

    Wang Xiaoming

    2005-01-01

    The formation of borides in an Al-3 wt.%B master alloy, produced via chemical reactions of KBF 4 and aluminium has been investigated. The chemical reactions produce boron, which dissolves into molten aluminium and subsequently forms aluminium borides. Backscattered electron imaging (BEI) of the Al-3 wt.%B master alloy under a scanning electron microscope (SEM) revealed the presence of two types of phases that contain different levels of boron. Combined with X-ray diffraction (XRD) results, the two types of phases are identified as AlB 2 on AlB 12 . This gives a direct evidence for a peritectic reaction of AlB 12 and aluminium, which produces AlB 2 . The thermodynamic properties of the reactions that may be involved are examined, and the presence of AlB 12 phase in the master alloy explained. The observed microstructure is explained according to the peritectic reaction in an Al-B phase diagram. The stability of AlB 2 and AlB 12 at lower temperature than 975 deg. C is clarified

  13. Construction and evaluation of multi-component Zn-Al based bearing alloys (Zn-Al-Si, Zn-Al-Cu)

    International Nuclear Information System (INIS)

    Shahmiri, M.; Shahin, K.

    2001-01-01

    Zn-Al based alloys, with excellent mechanical properties, are finding increasing applications in various industries, especially bearing and bushing fields. Observed dimensional instabilities, in their multicomponent systems, (e. g. Zn-Al-Si and, Zn-Al Si-Cu), is believed to be as the result of some kinds of phase transformation, due to the temperature variations, while in service. Profound understanding of the phase transformations due to the temperature variation, requires detailed evaluations of the isothermal sections of the multi-components phase diagrams of Zn-Al-Si and, Zn-Al-Si-Cu alloy systems. In the present article, the isothermal sections of the aforementioned ternary and quaternary systems in the solid state regions have been investigated and observed phase transitions have been critically evaluated

  14. The Existence of a Designer Al=Al Double Bond in the LiAl2 H4- Cluster Formed by Electronic Transmutation.

    Science.gov (United States)

    Lundell, Katie A; Zhang, Xinxing; Boldyrev, Alexander I; Bowen, Kit H

    2017-12-22

    The Al=Al double bond is elusive in chemistry. Herein we report the results obtained via combined photoelectron spectroscopy and ab initio studies of the LiAl 2 H 4 - cluster that confirm the formation of a conventional Al=Al double bond. Comprehensive searches for the most stable structures of the LiAl 2 H 4 - cluster have shown that the global minimum isomer I possesses a geometric structure which resembles that of Si 2 H 4 , demonstrating a successful example of the transmutation of Al atoms into Si atoms by electron donation. Theoretical simulations of the photoelectron spectrum discovered the coexistence of two isomers in the ion beam, including the one with the Al=Al double bond. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Characterization of N-polar AlN in GaN/AlN/(Al,Ga)N heterostructures grown by metal-organic chemical vapor deposition

    Science.gov (United States)

    Li, Haoran; Mazumder, Baishakhi; Bonef, Bastien; Keller, Stacia; Wienecke, Steven; Speck, James S.; Denbaars, Steven P.; Mishra, Umesh K.

    2017-11-01

    In GaN/(Al,Ga)N high-electron-mobility transistors (HEMT), AlN interlayer between GaN channel and AlGaN barrier suppresses alloy scattering and significantly improves the electron mobility of the two-dimensional electron gas. While high concentrations of gallium were previously observed in Al-polar AlN interlayers grown by metal-organic chemical vapor deposition, the N-polar AlN (Al x Ga1-x N) films examined by atom probe tomography in this study exhibited aluminum compositions (x) equal to or higher than 95% over a wide range of growth conditions. The also investigated AlN interlayer in a N-polar GaN/AlN/AlGaN/ S.I. GaN HEMT structure possessed a similarly high x content.

  16. KRITIK ATAS KRITIK EPISTEMOLOGI TAFSIR M. ABIED AL JABIRI: Studi Kritis atas Madkhal ila al Quran al Karim

    Directory of Open Access Journals (Sweden)

    Ahmad Fawaid

    2015-12-01

    Full Text Available This paper critically views the epistemology of Muhammad Abid al Jabiri’s interpretation in his book, Madkhal ila al Quran al Karim. His latest work is projected to make the Quran relevant to mankind today and with certainly critiquing classical Quranic studies that have been constructed by previous scholars. Starting from Arab criticism, which is expected to synergize the gap between Turath and modernity, al Jabiri tried out his theory in the realm of Quranic studies oriented to maintain its originality and interpretation from sectarian influence. Focusing on al Jabiri’s review on the Quran, this paper examines and associates some of the problems with the epistemology of critique in Arab reasoning. Finally, it is inferred that the epistemologic offer of al Jabiri used in Turath is not fully applicable in Quranic studies for several reasons. First, the Quranic studies existed within the chain of sanad in its formation. Secondly, at the application stage, al Jabri often overlooked the sanad and narrations from the companions.

  17. Lubrication performance and mechanisms of Mg/Al-, Zn/Al-, and Zn/Mg/Al-layered double hydroxide nanoparticles as lubricant additives

    International Nuclear Information System (INIS)

    Li, Shuo; Bhushan, Bharat

    2016-01-01

    Highlights: • Mg/Al-, Zn/Al- and Zn/Mg/Al-layered double hydroxide were synthesized. • Mg/Al-LDH had superior tribological performance compared to other LDHs. • The best thermal stability of Mg/Al-LDH was responsible for its friction property. - Abstract: Solid lubricant particles are commonly used as oil additives for low friction and wear. Mg/Al-, Zn/Al-, and Zn/Mg/Al-layered double hydroxides (LDH) were synthesized by coprecipitation method. The benefits of LDH nanoparticles are that they can be synthesized using chemical methods where size and shape can be controlled, and can be modified organically to allow dispersal in fluids. The LDH nanoparticles were characterized by X-ray diffraction, scanning electron microscope, thermogravimetry, and differential scanning calorimetry. A pin-on-disk friction and wear tester was used for evaluating the friction and wear properties of LDH nanoparticles as lubricant additives. LDH nanoparticles have friction-reducing and anti-wear properties compared to oil without LDHs. Mg/Al-LDH has the best lubrication, possibly due to better thermal stability in severe conditions.

  18. Lubrication performance and mechanisms of Mg/Al-, Zn/Al-, and Zn/Mg/Al-layered double hydroxide nanoparticles as lubricant additives

    Energy Technology Data Exchange (ETDEWEB)

    Li, Shuo [School of Materials Science and Technology, China University of Geosciences (Beijing), 29 Xueyuan Road, Haidian Distract, Beijing 100083 (China); Nanoprobe Laboratory for Bio- & Nanotechnology and Biomimetics (NLBB), The Ohio State University, 201 W. 19th Avenue Columbus, OH 43210-1142 (United States); Bhushan, Bharat, E-mail: bhushan.2@osu.edu [Nanoprobe Laboratory for Bio- & Nanotechnology and Biomimetics (NLBB), The Ohio State University, 201 W. 19th Avenue Columbus, OH 43210-1142 (United States)

    2016-08-15

    Highlights: • Mg/Al-, Zn/Al- and Zn/Mg/Al-layered double hydroxide were synthesized. • Mg/Al-LDH had superior tribological performance compared to other LDHs. • The best thermal stability of Mg/Al-LDH was responsible for its friction property. - Abstract: Solid lubricant particles are commonly used as oil additives for low friction and wear. Mg/Al-, Zn/Al-, and Zn/Mg/Al-layered double hydroxides (LDH) were synthesized by coprecipitation method. The benefits of LDH nanoparticles are that they can be synthesized using chemical methods where size and shape can be controlled, and can be modified organically to allow dispersal in fluids. The LDH nanoparticles were characterized by X-ray diffraction, scanning electron microscope, thermogravimetry, and differential scanning calorimetry. A pin-on-disk friction and wear tester was used for evaluating the friction and wear properties of LDH nanoparticles as lubricant additives. LDH nanoparticles have friction-reducing and anti-wear properties compared to oil without LDHs. Mg/Al-LDH has the best lubrication, possibly due to better thermal stability in severe conditions.

  19. A randomised controlled trial comparing the effect of adjuvant ...

    African Journals Online (AJOL)

    Results: The duration of effective analgesia was longer in the midazolam group ... There was no significant difference (P 0.4047). ... events, peripheral vasoconstriction, and metabolic acido- .... determined and recorded every hour. ..... scriptions of chronic pain syndromes and definitions of ... Long-term intrathecal adminis-.

  20. Dakwah Kultural Bayt al-Qur’an al-Akbar Ukiran Kayu Khas Melayu Palembang

    Directory of Open Access Journals (Sweden)

    Reza Pahlevi

    2016-07-01

    Full Text Available Penelitian ini berusaha mengungkap berbagai fenomena yang menggambarkan serangkaian kegiatan dakwah kultural Bayt al-Qur’an al-Akbar Ukiran Khas Melayu Palembang. Sehingga dapat diperoleh sejumlah informasi mengenai berbagai upaya penerapan program yang dimaksud. Penelitian ini dapat disimpulkan, pertama kontribusi Bayt al-Qur’an al-Akbar Ukiran Khas Melayu Palembang terhadap perkembangan metode dakwah kultural adalah dakwah melalui seni. Kedua, Bayt al-Qur’an al-Akbar Ukiran Khas Melayu Palembang sebagai tempat Wisata Religi yang sangat signifikan.   This research tries to reveal the various phenomenon that describe a series of cultural propaganda activities Bayt al-Qur’an al-Akbar Ukiran Khas Melayu Palembang. In order to obtain some informations about the efforts of the implementation of the program in question. It can be concluded, the first contribution of Bayt al-Qur’an al-Akbar Ukiran Khas Melayu Palembang on the development of methods of cultural propaganda is propaganda through art. Second Bayt al-Qur’an al-Akbar Ukiran Khas Melayu Palembang as a very significant Religious Tourism.

  1. Optical phonon scattering on electronic mobility in Al2O3/AlGaN/AlN/GaN heterostructures

    Science.gov (United States)

    Zhou, X. J.; Qu, Y.; Ban, S. L.; Wang, Z. P.

    2017-12-01

    Considering the built-in electric fields and the two-mode property of transverse optical phonons in AlGaN material, the electronic eigen-energies and wave functions are obtained by solving Schrödinger equation with the finite difference method. The dispersion relations and potentials of the optical phonons are given by the transfer matrix method. The mobility of the two dimensional electron gas influenced by the optical phonons in Al2O3/AlGaN/AlN/GaN heterostructures is investigated based on the theory of Lei-Ting force balance equation. It is found that the scattering from the half-space phonons is the main factor affecting the electronic mobility, and the influence of the other phonons can be ignored. The results show that the mobility decreases with increasing the thicknesses of Al2O3 and AlN layers, but there is no definite relationship between the mobility and the thickness of AlGaN barrier. The mobility is obviously reduced by increasing Al component in AlGaN crystal to show that the effect of ternary mixed crystals is important. It is also found that the mobility increases first and then decreases as the increment of the fixed charges, but decreases always with increasing temperature. The heterostructures constructed here can be good candidates as metal-oxide-semiconductor high-electron-mobility-transistors since they have higher electronic mobility due to the influence from interface phonons weakened by the AlN interlayer.

  2. Al2O3 adherence on CoCrAl alloys

    International Nuclear Information System (INIS)

    Kingsley, L.M.

    1980-04-01

    Adherence of protective oxides on NiCrAl and CoCrAl superalloys has been promoted by a dispersion of a highly oxygen reactive element or its oxide being produced within the protection system. Two aspects of this subject are investigated here: the use of Al 2 O 3 as both the dispersion and protective oxide; and the production of an HfO 2 dispersion while simultaneously aluminizing the alloy. It was found that an Al 2 O 3 dispersion will act to promote the adherence of an external scale of Al 2 O 3 to a degree comparable to previously tested dispersions and an HfO 2 dispersion comparable to that produced by a Rhines pack treatment is produced during aluminization

  3. 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.' ' '

  4. All About ALS

    Science.gov (United States)

    ... Subscribe August 2015 Print this issue All About ALS Understanding a Devastating Disorder En español Send us ... Sports Concussions Wise Choices How Can I Help ALS Research? If you have ALS, join the National ...

  5. Atomistic simulations of diffusion mechanisms in off-stoichiometric Al-rich Ni3Al

    International Nuclear Information System (INIS)

    Duan, Jinsong

    2007-01-01

    This paper presents dynamics simulation results of diffusion in off-stoichiometric Al-rich Ni 3 Al (Ni 73 Al 27 ) at temperature ranging from 1300 to 1550 K. The interatomic forces are described by the Finnis-Sinclair type N-body potentials. Particular attention is devoted to the effect of the extra 2% of Al atoms sitting on the Ni sublattice as antisite point defects (Al Ni ) on diffusion. Simulation results show that Ni atoms mainly diffuse through the Ni sublattice at the temperatures investigated. Al atoms diffuse via both the intrasublattice and antistructure bridge (ASB) mechanisms. The contribution to Al diffusion from the ASB mechanism decreases at the lower temperature (T Ni ) enhances both Al and Ni diffusion in Ni 73 Al 27 . The Ni-Al coupled diffusion effect is observed and understood at the atomic level for the first time

  6. Methodology and Characteristics of Zad al-masir fi ‘ilm al-tafsirby AllamaIbn al-Jawzī (Urdu

    Directory of Open Access Journals (Sweden)

    Dr. Muhammad Riaz al Azhari

    2017-01-01

    Full Text Available This article describes the methodology and characteristics of Zad al-masir fi ‘ilm al-tafsir. This is one the finest work of AllamaIbn al-Jawzī, a 6th century prominent Interpreter. Several editions of this Tafsir have been published. However, the edition of dar al-kitab al-‘arbi, Beirut published in four volumes is selected for this study. This exegesis is based on conventional narrations, authentic quotations from the Islamic Scholars and lingual & grammatical discussions. As a witness, causes of verses (asbabal-Nuz┴l,Makki and MadaniSurah’s (chapters, the abrogating and abrogated verses (al-nasikhwal-mans┴kh and Islamic jurisprudence have been discussed in it where needed. The quality of this translation which is admirable is that mostly authentic Ahadith from original sources, and references to well known basic books in relevant discussions have been described. `

  7. Phenotypic and genotypic studies of ALS cases in ALS-SMA families.

    Science.gov (United States)

    Corcia, Philippe; Vourc'h, Patrick; Blasco, Helene; Couratier, Philippe; Dangoumau, Audrey; Bellance, Remi; Desnuelle, Claude; Viader, Fausto; Pautot, Vivien; Millecamps, Stephanie; Bakkouche, Salah; Salachas, FranÇois; Andres, Christian R; Meininger, Vincent; Camu, William

    2018-03-01

    Amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA) are the most frequent motor neuron disorders in adulthood and infancy, respectively. There is a growing literature supporting common pathophysiological patterns between those disorders. One important clinical issue for that is the co-occurrence of both diseases within a family. To collect families in which ALS and SMA patients co-exist and describe the phenotype and the genotype of ALS patients. Nine families with co-occurrence of SMA and ALS have been gathered over the last 15 years. Epidemiological, phenotype and genetic status were collected. Out of the nine families, six corresponded to the criteria of familial ALS (FALS). Clinical data were available for 11 patients out of the 15 ALS cases. Mean age of onset was 58.5 years, site of onset was lower limbs in nine cases (81.8%), median duration was 22 months. Four ALS patients carried a mutation: three mutations in SOD1 gene (G147N in two cases and one with E121G) and one repeat expansion in the C9ORF72 gene. Three patients had abnormal SMN1 copy numbers. While the high proportion of familial history of ALS cases in these ALS-SMA pedigrees could have suggested that these familial clusters of the two most frequent MND rely on a genetic background, we failed to exclude that this occurred by chance.

  8. Eutectic microstructures of Al-ThA13 and Al-UA14 alloys

    International Nuclear Information System (INIS)

    Vieira, R.R.; Ambrozio Filho, F.

    1990-01-01

    This paper deals on the microstructures of systems Al-ThAl3 and Al-UAL4, which are composed by a non faceted phase (aluminium) and an intermetallic phase (ThAl3 or UAL4) which is normally faceted phase. (C.M.)

  9. Interface reactions in the Al-Si-SiC and Mg-Al-Al{sub 2}O{sub 3} composite systems

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, P.K. [Commission of the European Communities, Petten (Netherlands). Inst. for Advanced Materials; Fazal-Ur-Rehman [Imperial Coll. of Science, Technology and Medicine, London (United Kingdom). Dept. of Materials; Fox, S. [Imperial Coll. of Science, Technology and Medicine, London (United Kingdom). Dept. of Materials; Flower, H.M. [Imperial Coll. of Science, Technology and Medicine, London (United Kingdom). Dept. of Materials; West, D.R.F.

    1995-12-31

    Structural and compositional observations are reported on the influence of the interfaces on the mechanisms and kinetics of liquid metal-ceramic reactions in Al-SiC, Al-Si-SiC, Mg-Al{sub 2}O{sub 3} and Mg-Al-Al{sub 2}O{sub 3} composites. The aluminium based materials contained up to 20 vol% SiC in particulate form, and were produced by a spray casting process; subsequently the interface reactions were studied in samples heated to temperatures up to 1100 C. The reaction product was Al{sub 4}C{sub 3} in both Al-SiC and Al-Si-SiC composites. The influence of the crystallography and topology of the SiC particle surfaces on the nucleation of the Al{sub 4}C{sub 3} has been demonstrated; surface asperities play an important role. Growth of nuclei proceeds to form continuous reaction product layers which control the subsequent kinetics. The magnesium based composites contained 5 vol% Al{sub 2}O{sub 3} fibres (3 {mu}m in diameter), and were produced by a liquid infiltration process. SD Safimax fibres with relatively low and high porosity, and also RF Saffil fibres, with a silica binder, were investigated. Fibre porosity plays a major role in accelerating the penetration of Mg into the fibres with reaction to form MgO. Silica binder on the fibre surface transforms to MgO. The reaction rate was reduced by the presence of aluminium in the matrix. The factors controlling the reactions in the aluminium and magnesium based composites are compared. (orig.)

  10. KONSTRUKSI FIQH BUKHARI DALAM KITAB AL-JAMI’ AL-SHAHIH

    Directory of Open Access Journals (Sweden)

    Abdul Sattar

    2011-06-01

    Popularitas Imam Bukhari sebagai penyusun kitab Hadits memiliki posisi yang tinggi di kalangan masyarakat muslim. Kitab Al-Jami ‘al-Shahih karya Imam  Bukhari dianggap sebagai koleksi hadits terbaik setelah Quran. Namun, tidak ada banyak informasi tentang kemampuannya di bidang Hukum Islam (fiqh. Ada beberapa pertanyaan yang dapat diajukan dalam hal tersebut;  pertama, apakah pemikiran Imam Bukhari dipengaruh salah satu dari empat fuqaha Sunni saat menulis al-Jami ‘al-Shahih?. Kedua, apa yang diupayakan Imam Bukhari untuk mengartikulasikan pemikirannya tentang hukum Islam? Dengan menggunakan pendekatan eksploratif, verifikatif dan hermenetical, artikel ini akan mengungkapkan bahwa Imam Bukhari tidak berada di bawah pengaruh madhab tertentu dalam mengartikulasikan pemikirannya tentang hukum Islam. Dia mengartikulasikan pandangannya dengan cara yang unik dan execelent berdasarkan kapasitasnya sebagai muhaddits.

  11. La "historia de los omeyas de al-Andalus" en los Masalik al-Absar

    OpenAIRE

    Molina, Luis

    2005-01-01

    [ES]Los Masalik al-absar de Ibn Fadl Allah al-`Umari incluyen un breve resumen de la Historia de los omeyas de al-Andalus. En este trabajo se analizan las relaciones textuales entre ese pasaje y el Muqtabis de Ibn Hayyan, crónica que resulta ser la fuente casi única utilizada por al-`Umari para redactar ese capítulo. [EN]The Masalik al-absar by Ibn Fadl Allah al-`Umari contains a brief summary of the Umayyad history in al-Andalus. In this article, the textual relationship between this p...

  12. Cryptanalysis of Lin et al.'s Efficient Block-Cipher-Based Hash Function

    NARCIS (Netherlands)

    Liu, Bozhong; Gong, Zheng; Chen, Xiaohong; Qiu, Weidong; Zheng, Dong

    2010-01-01

    Hash functions are widely used in authentication. In this paper, the security of Lin et al.'s efficient block-cipher-based hash function is reviewed. By using Joux's multicollisions and Kelsey et al.'s expandable message techniques, we find the scheme is vulnerable to collision, preimage and second

  13. From Kitāb al-ḥadā’iq to Kitāb al-dawā’ir: Reconsidering Ibn al-Sīd al-Batalyawsī’s Philosophical Treatise

    Directory of Open Access Journals (Sweden)

    Eliyahu, Ayala

    2015-06-01

    Full Text Available The philosophical treatise known as Kitāb al-ḥadā’iq is generally ascribed to the 12th century Andalusian author Ibn al-Sīd al-Batalyawsī, although this attribution is sometimes contested. This paper offers a new interpretation of the title, textual history, authorship, sources, and literary genre of this treatise, on the basis of new textual evidence, a reexamination of known evidence, and a comparison between the treatise and Batalyawsī’s works. The conclusions of this study are first, that Kitāb al-ḥadā’iq was not the treatise’s original title, and therefore it should be renamed Kitāb al-dawā’ir; second, that Kitāb al-dawā’ir was originally part of (one of the versions of Batalyawsī’s Kitāb al-masā’il; and third, that the textual and stylistic similarities between this treatise and Batalyawsī’s other works prove the authenticity of the treatise’s attribution to Batalyawsī. In addition, new findings regarding Batalyawsī’s use of formulas from the Rasā’il Ikhwān al-Safā, in Kitāb al-dawā’ir and Kitāb al-masā’il provide further evidence for the deep impact of the Ikhwān on Batalyawsī’s thought, as well as for the close connection between Kitāb al-dawā’ir and Kitāb al-masā’il. This connection is further highlighted according to the attribution of both treatises to the genre of questions and answers in Arabic literature. The evidence gathered in this paper supports the claim that Batalyawsī’s Kitāb al-dawā’ir should be seen as an integral part of his literary oeuvre, as well as of Andalusian philosophical literature in general.Generalmente el tratado filosófico conocido como Kitāb al-ḥadā’iq se asocia al autor andalusí del siglo XII Ibn al-Sid al-Batalyawsī, aunque esta atribución ha sido discutida en ocasiones. Este artículo ofrece una nueva interpretación del título, la historia del texto, la autoría, las fuentes e incluso del género literario al que se

  14. Kinetics of oxidation of acidic amino acids by sodium N

    Indian Academy of Sciences (India)

    Asp)) by sodium N-bromobenzenesulphonamide (bromamine-B or BAB) has been carried out in aqueous HClO4 medium at 30°C. The rate shows firstorder dependence each on [BAB]o and [amino acid]o and inverse first-order on [H+]. At [H+] > ...

  15. Theory and X-ray Absorption Spectroscopy for Aluminum Coordination Complexes – Al K-Edge Studies of Charge and Bonding in (BDI)Al, (BDI)AlR2, and (BDI)AlX2 Complexes.

    Science.gov (United States)

    Altman, Alison B; Pemmaraju, C D; Camp, Clément; Arnold, John; Minasian, Stefan G; Prendergast, David; Shuh, David K; Tyliszczak, Tolek

    2015-08-19

    Polarized aluminum K-edge X-ray absorption near edge structure (XANES) spectroscopy and first-principles calculations were used to probe electronic structure in a series of (BDI)Al, (BDI)AlX2, and (BDI)AlR2 coordination compounds (X = F, Cl, I; R = H, Me; BDI = 2,6-diisopropylphenyl-β-diketiminate). Spectral interpretations were guided by examination of the calculated transition energies and polarization-dependent oscillator strengths, which agreed well with the XANES spectroscopy measurements. Pre-edge features were assigned to transitions associated with the Al 3p orbitals involved in metal-ligand bonding. Qualitative trends in Al 1s core energy and valence orbital occupation were established through a systematic comparison of excited states derived from Al 3p orbitals with similar symmetries in a molecular orbital framework. These trends suggested that the higher transition energies observed for (BDI)AlX2 systems with more electronegative X(1-) ligands could be ascribed to a decrease in electron density around the aluminum atom, which causes an increase in the attractive potential of the Al nucleus and concomitant increase in the binding energy of the Al 1s core orbitals. For (BDI)Al and (BDI)AlH2 the experimental Al K-edge XANES spectra and spectra calculated using the eXcited electron and Core-Hole (XCH) approach had nearly identical energies for transitions to final state orbitals of similar composition and symmetry. These results implied that the charge distributions about the aluminum atoms in (BDI)Al and (BDI)AlH2 are similar relative to the (BDI)AlX2 and (BDI)AlMe2 compounds, despite having different formal oxidation states of +1 and +3, respectively. However, (BDI)Al was unique in that it exhibited a low-energy feature that was attributed to transitions into a low-lying p-orbital of b1 symmetry that is localized on Al and orthogonal to the (BDI)Al plane. The presence of this low-energy unoccupied molecular orbital on electron-rich (BDI)Al distinguishes

  16. Thermodynamic properties of Al-Mn, Al-Cu, and Al-Fe-Cu melts and their relations to liquid and quasicrystal structure

    International Nuclear Information System (INIS)

    Zaitsev, A I; Zaitseva, N E; Shimko, R Yu; Arutyunyan, N A; Dunaev, S F; Kraposhin, V S; Lam, Ha Thanh

    2008-01-01

    Thermodynamic properties of molten Al-Mn, Al-Cu and Al-Fe-Cu alloys in a wide temperature range of 1123-1878 K and the whole range of concentrations have been studied using the integral effusion method and Knudsen mass spectrometry. Thermodynamic functions of melts were described by the associated solution model. The possibility of icosahedral quasicrystal (i-QC) precipitation from liquid Al-Mn and Al-Cu-Fe alloys was found to be a consequence of the existence in liquid associates (clusters). A geometric model is suggested for the structure of associates in liquid

  17. Sintering Behavior of CNT Reinforced Al6061 and Al2124 Nanocomposites

    Directory of Open Access Journals (Sweden)

    Nouari Saheb

    2014-01-01

    Full Text Available Ball milling and spark plasma sintering were successfully used to produce carbon nanotube reinforced Al6061 and Al2124 nanocomposites which have potential applications in the fields of aerospace, automotive, electronics, and high precision instrumentation. Al2124 and Al6061 nanocomposite powders containing 0.5 to 2 wt.% CNTs prepared through sonication and wet ball milling were spark plasma sintered at 400, 450, and 500°C for 20 minutes under a pressure of 35 MPa. CNTs were better dispersed, and less agglomerated and had good adhesion to the matrix in composites containing 1 wt.% CNTs. The increase of CNT content to 2 wt.% led to the formation of CNT clusters which resulted in less uniform and homogenous composite powders. Almost full densification of Al6061 reinforced with CNTs was achieved at 500°C. Also, CNTs reinforced Al2124 nanocomposites reached very high densities at 500°C. Composites reinforced with 1 wt.% CNTs displayed better densification compared to composites containing 2 wt.% CNTs. The increase of CNTs content from 0.5 to 1 wt.% increased the hardness of the Al6061 and Al2124 alloys to maximum values. Further increase of CNTs content to 2 wt.% decreased the hardness to values lower than that of the monolithic alloys.

  18. Tetragonal phase in Al-rich region of U-Fe-Al system

    International Nuclear Information System (INIS)

    Meshi, L.; Zenou, V.; Ezersky, V.; Munitz, A.; Talianker, M.

    2005-01-01

    A new ternary aluminide U 2 FeAl 20 with the approximate composition Al-4.2at% Fe-8.5at% U was observed in the Al-rich corner of the U-Al-Fe system. Transmission electron microscopy and electron microdiffraction technique were used for characterization of the structure of this phase. It has a tetragonal unit cell with the parameters a=12.4A and c=10.3A and can be described by the space group I4-bar 2m

  19. Ilhaq al-Masa'il bi Nazairiha dan Penerapannya dalam Bahth al-Masa'il

    Directory of Open Access Journals (Sweden)

    Luthfi Hadi Aminuddin

    2013-11-01

    Full Text Available Abstract: Ilh}a>q al-Masa>’il bi Naz}a>iriha is one of the methods used by Nahdlatul Ulama in resisting the opinion based on (manhaji analytical concept of Islamic jurisprudence (the solution for complex social problems as the main purpose of Islamic shari’ah. As known that, up to now, ilh}a>q has been understood as a process of answering a new case by the way of equating to the old one which is written in the book called al-mu’tabarah. Such ilh}a>q has got many criticisms both from the definitions, procedures and its epistemogical footing. This paper is about to reveal how the NU clerics of Islam understand the concept of Ilh}a>q}, what its epistemological footing was and how the concept was applied in discussing many cases (bah}th al-masa>’il. Based on the writer’s study to several documents of decision results of NU that Ilh}a>q did not only simplify to equate the new cases with the old ones that have been freely discussed in the books of al-mu’tabarah, but both cases should have similar legal substance, that is, both should be under the decrees of laws of al-qawa> ‘id al-fiqhi>yah. Thus, Ilh}a>q is actually answering the problem by applying al-qawa>‘id al-fiqhi>yah, whereas the formulation al-qawa>‘id al-fiqhi>yah itself was set off from the examination of a number of furu>’ generated by qiya> s. This paper also found three variations of the implementation of Ilh}a>q in bah}th al-masa>’il. First, the application of Ilh}a>q was without mentioning al-qawa> ‘id al-fiqhi>yah which covered new cases (mulh}aq and the old case law that has been known in the books of fiqh (mulh}aq bih/attached to. Second, the application of Ilh}a>q was accompanied by mentioning mulh}aq bih and al-qawa> ‘id al-fiqhi>yah. Third, the application of Ilh}a>q, was only by the mentioning al-qawa> ‘id al-fiqhi>yah.

  20. Nanoindentation studies of ex situ AlN/Al metal matrix nanocomposites

    International Nuclear Information System (INIS)

    Fale, Sandeep; Likhite, Ajay; Bhatt, Jatin

    2014-01-01

    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

  1. Isothermal cross-sections of Sr-Al-Ge and Ba-Al-Ge systems at 673 K

    International Nuclear Information System (INIS)

    Kutsenok, N.L.; Yanson, T.I.

    1987-01-01

    X-ray and microstructural analyses are used to study phase equilibria in Sr-Al-Ge and Ba-Al-Ge systems. Existence of SrAl 2 Ge 2 , Sr(Al, Ge) 2 Ba(Al, Ge) 2 , Sr 3 Al 2 Ge 2 , Ba 3 Al 2 Ge 2 ternary compounds is confirmed, a new BaGe 4 binary compound and also new ternary compounds of approximate composition Sr 57 Al 30 Ge 13 and Ba 20 Al 40 Ge 40 , which crystal structure is unknown, are detected. Aluminium solubility in SrAl 4 and BaAl 4 binary compounds (0.05 atomic fraction) is determined. Ba(Al, Ge) 2 compound homogeneity region is defined more exactly (aluminium content varies from 0.27 to 0.51 at. fractions)

  2. Production of 26Al by spallation of Fe, Si, Al nuclei

    International Nuclear Information System (INIS)

    Paillard, P.

    1977-01-01

    Cross sections for 7 Be, 10 Be and 26 Al formation in Al, Si and Fe targets bombarded with 0.6 and 24GeV protons have been measured by using highly selective chemical separation and low level background counters. Results for 26 Al at 0.6GeV are in mb: 17.9 + or - 2.7 in Al, 12.5 + or - 2.5 in Si and 0.45 + or - 0.14 in Fe; at 24GeV 2.6 + or - 0.5mb in Fe. Results for 10 Be are not valid on account of experimental difficulties. It is deduced from these values of aluminium in cosmic ray propagation that 26 Al is not yet cosmic ray chronometer [fr

  3. 143 - 148_Makeri et al.

    African Journals Online (AJOL)

    USER

    2015-06-01

    Jun 1, 2015 ... Yuan et al., 2003), antimicrobial activity (Sundarrao et al., 1993; Betancur-Galvis et al., 1999; Takashi et al., 2006), anti-parasitic, anti-malarial activities (Alali et al., 1998; Jaramillo et al., 2000; Luna et al.,. 2005). This study evaluates the antibacterial activity of extract of stem –bark and leaf extracts of Annona.

  4. Phase relationships in the Al-rich region of the Al-Cu-Er system

    International Nuclear Information System (INIS)

    Zhang Ligang; Masset, Patrick J.; Cao Fuyong; Meng Fangui; Liu Libin; Jin Zhanpeng

    2011-01-01

    Research highlights: → One ternary phase τ 1 -Al 8 Cu 4 Er in Al-rich region with a composition of 59.4-60.4 at.% Al, 32.2-33.8 at.% Cu, and 6.4-7.7 at.% Er is observed in both as-cast and annealed alloys. At 673 K, the binary Al 3 Er phase dissolves about 3.51 at.% Cu. → The calculated solidification paths (based on the CALPHAD method) of as-cast alloys are in agreement with the experimental results. → It can be found that the resultant thermodynamic database can be applied to case studies of as-cast alloys, showing that the literature thermodynamic description of the Al-Cu-Er system is reliable as a working basis for computer-assisted alloy design. - Abstract: The Al-rich region of the ternary Al-Cu-Er system is investigated using the method of X-ray diffraction, scanning electron microscopy with energy dispersive X-ray spectroscopy. Phase equilibria in the Al-rich region of the Al-Cu-Er system at 673 K have been obtained, and the microstructures of as-cast alloys in the Al-rich region are also investigated. One ternary phase τ 1 -Al 8 Cu 4 Er with a composition of 59.4-60.4 at.% Al, 32.2-33.8 at.% Cu, and 6.4-7.7 at.% Er is observed in both as-cast and annealed alloys. At 673 K, the binary Al 3 Er phase dissolves about 3.51 at.% Cu. The calculated solidification paths (based on the CALPHAD method) of as-cast alloys are in agreement with the experimental results.

  5. Mechanical properties and deformation behavior of Al/Al7075, two-phase material

    International Nuclear Information System (INIS)

    Sherafat, Z.; Paydar, M.H.; Ebrahimi, R.; Sohrabi, S.

    2010-01-01

    In the present study, mechanical properties and deformation behavior of Al/Al7075, two-phase material were investigated. The two-phase materials were fabricated by mixing commercially pure Al powder with Al7075 chips and consolidating the mixture through hot extrusion process at 500 o C. Mechanical properties and deformation behavior of the fabricated samples were evaluated using tensile and compression tests. A scanning electron microscope was used to study the fracture surface of the samples including different amount of Al powder, after they were fractured in tensile test. The results of the tensile and compression tests showed that with decreasing the amount of Al powder, the strength increases and ductility decreases. Calculation of work hardening exponent (n) indicated that deformation behavior does not follow a regular trend. In a way that the n value was approved to be variable and a strong function of strain and Al powder wt% of the sample. The results of the fractography studies indicate that the type of fracture happened changes from completely ductile to nearly brittle by decreasing the wt% of Al powder from 90% to 40%.

  6. Inhibition of fructan-fermenting equine fecal bacteria and Streptococcus bovis by hops (Humulus lupulus L.) ß-acid

    Science.gov (United States)

    Aims: The goals were to determine if the '-acid from hops (Humulus lupulus L.) could be used to control fructan fermentation by equine hindgut microorganisms, and to verify the antimicrobial mode of action on the Streptococcus bovis, which has been implicated in fructan fermentation, hindgut acidos...

  7. A Scholar from Saray: Mawlana Zada al-Sarayi (754/1353–791/1389 in the Biographical Dictionary of Taqi al-Din al-Maqrizi (766/1365–845/1441 “Kitab al-Muqaffa al-Kabir” (The Great Rhymed Book

    Directory of Open Access Journals (Sweden)

    D.R. Zaynuddinov

    2017-03-01

    Full Text Available Research objective: to introduce into academic circulation previously unknown source on the Golden Horde history. Research materials: biographical dictionary of Taqi al-Din al-Maqrizi (766/1365 – 845/1441 “Kitab al-Muqaffa al-Kabir” (The Great Rhymed Book. Results and novelty of the research: This article contains materials from the works of historians engaged in the narrative biography, which V.G. Tiesenhausen did not include in his “Collection of Materials on the Golden Horde history (extract from Arab writings”, although their writings contain very valuable information about the Golden Horde History. Research novelty consists in the fact that the author of this article presents one paragraph from biographical dictionary of Taqi al-Din al-Maqrizi, whose article number 421 provides information about a scholar from Saray – Mawlana Zada al-Sarayi. The author provides its translation and commentary referring to the more than ten medieval Arab sources. After receiving basic education at home, Mawlana Zada al-Sarayi traveled to many Eastern countries in search of knowledge and after having received high recognition he settled in Cairo as a teacher of Sharia Sciences. Despite the fact that his life was interrupted at an early age (36 years, he left a deep mark in science. His son Muhibbu al-Din (Cairo, 791/1389 – Mecca, Friday, the 3rd of Dhu al-Hijjah 859/13 November 1455 also became a great scholar as well as an imam of Sultan al-Ashraf Barsbay himself and other sultans after him. Nisba al-Sarayi sounded on the lips of the Ulema of the East as a symbol of learnedness and high temper. As a result of research it must be said that the study of life of Mawlana Zada al-Sarayi (754/1353 – 791/1389 and the number of migrants from Desht-i Kipchak in Egypt will help researchers in a deeper and more detailed study of the Golden Horde history.

  8. Improved AlGaN/GaN HEMTs Grown on Si Substrates Using Stacked AlGaN/AlN Interlayer by MOCVD

    International Nuclear Information System (INIS)

    Wang Yong; Yu Nai-Sen; Li Ming; Lau Kei-May

    2011-01-01

    AlGaN/GaN high electron mobility transistors (HEMTs) are grown on 2-inch Si (111) substrates by MOCVD. The stacked AlGaN/AlN interlayer with different AlGaN thickness and indium surfactant doped is designed and optimized to relieve the tensile stress during GaN epitaxial growth. The top 1.0μm GaN buffer layer grown on the optimized AlGaN/AlN interlayer shows a crack-free and shining surface. The XRD results show that GaN(002) FWHM is 480 arcsec and GaN(102) FWHM is 900 arcsec. The AGaN/GaN HEMTs with optimized and non-optimized AlGaN/AlN interlayer are grown and processed for comparison and the dc and rf characteristics are characterized. For the dc characteristics of the device with optimized AlGaN/AlN interlayer, maximum drain current density I dss of 737mA/mm, peak transconductance G m of 185mS/mm, drain leakage current density I ds of 1.7μA/mm, gate leakage current density I gs of 24.8 μA/mm and off-state breakdown voltage V BR of 67 V are achieved with L g /W g /L gs /L gd = 1/10/1/1 μm. For the small signal rf characteristics of the device with optimized AlGaN/AlN interlayer, current gain cutoff frequency f T of 8.3 GHz and power gain cutoff frequency f max of 19.9 GHz are achieved with L g /W g /L gs /L gd = 1/100/1/1 μm. Furthermore, the best rf performance with f T of 14.5 GHz and f max of 37.3 GHz is achieved with a reduced gate length of 0.7μm. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  9. 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.

  10. Predicting glass-forming compositions in the Al-La and Al-La-Ni systems

    International Nuclear Information System (INIS)

    Gargarella, P.; de Oliveira, M.F.; Kiminami, C.S.; Pauly, S.; Kuehn, U.; Bolfarini, C.; Botta, W.J.; Eckert, J.

    2011-01-01

    Research highlights: → The glass-forming ability of the Al-La and Al-La-Ni systems was studied using the λ* and the λ.Δe criteria. → Both criteria predicted with just 1% at. of error the best glass-former verified so far in the Al-La system. → Four new glass-former compositions could be predicted in the Al-La-Ni system using the λ.Δe criterion. → The best glass-former reported so far in the Al-La-Ni system was found. - Abstract: In this work, a criterion considering the topological instability (λ) and the differences in the electronegativity of the constituent elements (Δe) was applied to the Al-La and Al-Ni-La systems in order to predict the best glass-forming compositions. The results were compared with literature data and with our own experimental data for the Al-La-Ni system. The alloy described in the literature as the best glass former in the Al-La system is located near the point with local maximum for the λ.Δe criterion. A good agreement was found between the predictions of the λ.Δe criterion and literature data in the Al-La-Ni system, with the region of the best glass-forming ability (GFA) and largest supercooled liquid region (ΔT x ) coinciding with the best compositional region for amorphization indicated by the λ.Δe criterion. Four new glassy compositions were found in the Al-La-Ni system, with the best predicted composition presenting the best glass-forming ability observed so far for this system. Although the λ.Δe criterion needs further refinements for completely describe the glass-forming ability in the Al-La and Al-La-Ni systems, the results demonstrated that this criterion is a good tool to predict new glass-forming compositions.

  11. Electric quadrupole moments of neutron-rich nuclei {sup 32}Al and {sup 31}Al

    Energy Technology Data Exchange (ETDEWEB)

    Kameda, D., E-mail: kameda@ribf.riken.jp; Ueno, H. [RIKEN Nishina Center (Japan); Asahi, K.; Nagae, D.; Takemura, M.; Shimada, K. [Tokyo Institute of Technology, Department of Physics (Japan); Yoshimi, A.; Nagatomo, T.; Sugimoto, T. [RIKEN Nishina Center (Japan); Uchida, M.; Arai, T.; Takase, K.; Suda, S.; Inoue, T. [Tokyo Institute of Technology, Department of Physics (Japan); Murata, J.; Kawamura, H. [Rikkyo University, Department of Physics (Japan); Watanabe, H. [Australian National University, Department of Nuclear Physics (Australia); Kobayashi, Y.; Ishihara, M. [RIKEN Nishina Center (Japan)

    2007-11-15

    The electric quadrupole moments for the ground states of {sup 32}Al and {sup 31}Al have been measured by the {beta} ray-detected nuclear quadrupole resonance method. Spin-polarized {sup 32}Al and {sup 31}Al nuclei were obtained from the fragmentation of {sup 40}Ar projectiles at E/A = 95 MeV/nucleon, and were implanted in a single crystal {alpha}-Al{sub 2}O{sub 3} stopper. The measured Q moment of {sup 32}Al, |Q({sup 32}Al)| = 24(2) mb, is in good agreement with a conventional shell-model calculation with a full sd model space and empirical effective charges, while that of {sup 31}Al is considerably smaller than the sd calculations.

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

    International Nuclear Information System (INIS)

    Markoli, B.; Spaic, S.; Zupanic, F.

    2001-01-01

    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 (α Al , β Si , Al 3 Sm, Al 2 Si 2 Sm and AlSiSm) with following characteristic invariant reaction sequences: ternary eutectic reaction L → α Al + β Si + Al 2 Si 2 Sm, and two liquidus transition reactions, i. e., L + Al 3 Sm → α Al + AlSiSm, and L + AlSiSm → α Al + Al 2 Si 2 Sm. 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.)

  13. Disordered crystal structure of 20H-AlON, Al10O3N8

    International Nuclear Information System (INIS)

    Banno, Hiroki; Funahashi, Shiro; Asaka, Toru; Hirosaki, Naoto; Fukuda, Koichiro

    2015-01-01

    The disordered crystal structure of 20H-AlON (Al 10 O 3 N 8 ) was determined by combined use of X-ray powder diffraction and transmission electron microscopy. The title compound is hexagonal with space group P6 3 /mmc (Z=2) and the unit-cell dimensions are a=0.307082(5) nm, c=5.29447(8) nm and V=0.432376(12) nm 3 . The structural model showed the positional disordering of three of the six Al sites in the unit cell. The reliability indices calculated from the Rietveld method were R wp =6.97%, S (=R wp /R e )=1.68, R p =5.45%, R B =5.13% and R F =4.56%. We interpreted the disordered structure of 20H-AlON as a statistical average of six different types of ordered structural configurations, which are composed of an octahedral [Al(O, N) 6 ] layer and tetrahedral [Al(O, N) 4 ] layers. We demonstrated the high correlations between the hexagonal unit-cell dimensions and the octahedral layer concentrations for AlON and SiAlON polytypoids. - Graphical abstract: Variations of a and c/(n O +n T ) with n O /(n O +n T ). The a and c are the hexagonal unit-cell dimensions of AlON, SiAlON and AlN. The n O and n T are, respectively, the numbers of octahedral and tetrahedral layers in the unit cells. The unit-cell dimensions in literature are plotted in black plus for AlON and black cross for SiAlON. The unit-cell dimensions of AlN are a=0.3110 nm and c=0.4980 nm. - Highlights: • Crystal structure of Al10O3N8 is determined by laboratory X-ray powder diffraction. • The atom arrangements are represented by the split-atom model. • Six types of ordered atom arrangements are derived from the disordered structure. • Hexagonal unit-cell dimensions changed systematically for AlON and SiAlON compounds

  14. 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

  15. FRACTIONAL RECRYSTALLIZATION KINETICS IN DIRECTLY COLD ROLLED Al-Mg, Al-Mg-Sc AND Al-Mg-Sc-Zr ALLOY

    Directory of Open Access Journals (Sweden)

    M. S. Kaiser

    2014-12-01

    Full Text Available The evaluation of texture as a function of recrystallization has been characterized for directly cold rolled Al-6Mg, Al-6Mg-0.4Sc and Al-6Mg-0.4Sc-0.2Zr alloys. Samples were annealed isothermally at 400 °C for 1 to 240 minutes to allow recrystallization. Recrystallization kinetics of the alloys is analyzed from the micro-hardness variation. Isothermally annealed samples of aluminum alloys were also studied using JMAK type analysis to see if there exists any correlation between the methods. Recrystallization fraction behavior between two methods the scandium added alloys show the higher variation due to precipitation hardening and higher recrystallization behavior. The scandium and zirconium as a combined shows the more variation due to formation of Al3(Sc, Zr precipitate. From the microstructure it is also observed that the base Al-Mg alloy attained almost fully re-crystallized state after annealing at 400 °C for 60 minutes

  16. Chemical failure modes of AlQ3-based OLEDs: AlQ3 hydrolysis.

    Science.gov (United States)

    Knox, John E; Halls, Mathew D; Hratchian, Hrant P; Schlegel, H Bernhard

    2006-03-28

    Tris(8-hydroxyquinoline)aluminum(III), AlQ3, is used in organic light-emitting diodes (OLEDs) as an electron-transport material and emitting layer. The reaction of AlQ3 with trace H2O has been implicated as a major failure pathway for AlQ3-based OLEDs. Hybrid density functional calculations have been carried out to characterize the hydrolysis of AlQ3. The thermochemical and atomistic details for this important reaction are reported for both the neutral and oxidized AlQ3/AlQ3+ systems. In support of experimental conclusions, the neutral hydrolysis reaction pathway is found to be a thermally activated process, having a classical barrier height of 24.2 kcal mol(-1). First-principles infrared and electronic absorption spectra are compared to further characterize AlQ3 and the hydrolysis pathway product, AlQ2OH. The activation energy for the cationic AlQ3 hydrolysis pathway is found to be 8.5 kcal mol(-1) lower than for the neutral reaction, which is significant since it suggests a role for charge imbalance in promoting chemical failure modes in OLED devices.

  17. Study on Mg/Al Weld Seam Based on Zn–Mg–Al Ternary Alloy

    Directory of Open Access Journals (Sweden)

    Liming Liu

    2014-02-01

    Full Text Available Based on the idea of alloying welding seams, a series of Zn–xAl filler metals was calculated and designed for joining Mg/Al dissimilar metals by gas tungsten arc (GTA welding. An infrared thermography system was used to measure the temperature of the welding pool during the welding process to investigate the solidification process. It was found that the mechanical properties of the welded joints were improved with the increasing of the Al content in the Zn–xAl filler metals, and when Zn–30Al was used as the filler metal, the ultimate tensile strength could reach a maximum of 120 MPa. The reason for the average tensile strength of the joint increasing was that the weak zone of the joint using Zn–30Al filler metal was generated primarily by α-Al instead of MgZn2. When Zn–40Al was used as the filler metal, a new transition zone, about 20 μm-wide, appeared in the edge of the fusion zone near the Mg base metal. Due to the transition zones consisting of MgZn2- and Al-based solid solution, the mechanical property of the joints was deteriorated.

  18. Optical, structural, and nuclear scientific studies of AlGaN with high Al composition

    Science.gov (United States)

    Lin, Tse Yang; Chung, Yee Ling; Li, Lin; Yao, Shude; Lee, Y. C.; Feng, Zhe Chuan; Ferguson, Ian T.; Lu, Weijie

    2010-08-01

    AlGaN epilayers with higher Al-compositions were grown by Metalorganic Chemical Vapor Deposition (MOCVD) on (0001) sapphire. Trimethylgallium (TMGa), trimethylaluminium (TMAl) and NH3 were used as the source precursors for Ga, Al, and N, respectively. A 25 nm AlN nucleation layer was first grown at low-temperature of 590 °C at 300 Torr. Followed, AlxGa1-xN layers were grown at 1080 °C on low-temperature AlN nucleation layers. The heterostructures were characterized by a series of techniques, including x-ray diffraction (XRD), Rutherford backscattering (RBS), photoluminescence (PL), scanning electron microscopy (SEM) and Raman scattering. Precise Al compositions were determined through XRD, RBS, and SEM combined measurements. Room Temperature Raman Scattering spectra shows three major bands from AlGaN alloys, which are AlN-like, A1 longitudinal optical (LO) phonon modes, and E2 transverse optical (TO) band, respectively, plus several peak comes from the substrate. Raman spectral line shape analysis lead to an optical determination of the electrical property free carrier concentration of AlGaN. The optical properties of AlGaN with high Al composition were presented here.

  19. Ion-beam mixing and thermal annealing of Al--Nb and Al--Ta thin films

    International Nuclear Information System (INIS)

    Rai, A.K.; Bhattacharya, R.S.; Mendiratta, M.G.; Subramanian, P.R.; Dimiduk, D.M.

    1988-01-01

    Ion-beam mixing and thermal annealing of thin, alternating layers of Al and Nb, as well as Al and Ta, were investigated by selected area diffraction and Rutherford backscattering. The individual layer thicknesses were adjusted to obtain the overall compositions as Al 3 Nb and Al 3 Ta. The films were ion mixed with 1 MeV Au + ions at a dose of 1 x 10 16 ions cm/sup -2/ . Uniform mixing and amorphization were achieved for both Al--Nb and Al--Ta systems. Equilibrium crystalline Al 3 Nb and Al 3 Ta phases were formed after annealing of ion mixed amorphous films at 400 0 C for 6 h. Unmixed films, however, remained unreacted at 400 0 C for 1 h. Partial reaction was observed in the unmixed film of Al--Nb at 400 0 C for 6 h. After annealing at 500 0 C for 1 h, a complete reaction and formation of Al 3 Nb and Al 3 Ta phases in the respective films were observed. The influence of thermodynamics on the phase formation by ion mixing and thermal annealing is discussed

  20. Effect of elevated Al and pH on the growth and root morphology of Al-tolerant and Al-sensitive wheat seedlings in an acid soil

    Directory of Open Access Journals (Sweden)

    Md. Toufiq Iqbal

    2014-03-01

    Full Text Available Aluminium ion (Al3+ toxicity and hydrogen ion (H+ activity are the major constraints for plant growth in acid soil. This study was undertaken to determine the effect of pH and Al on the growth response and changes in root morphology of Al-tolerant (ET8 and Al-sensitive (ES8 wheat seedlings. Different levels of AlCl3 and CaCO3 were added to the soils to manipulate soil pH and extractable Al. The results showed that the bulk soil pH remained constant at pH 4.1 with further applications of AlCl3, and that the seedlings died at the 200 mg AlCl3/kg treatments. The ET8 seedlings responded better than the ES8 seedlings in both low and high Al and pH. The ET8 seedlings had higher root surface areas and root tip numbers than the ES8 seedlings in the Al treatment. In contrast, the ES8 had higher root diameters than the ET8 seedlings due to the elevated Al supply. Apoplast Al increased with the increase of soil available extractable Al, and declined with the decrease of soil extractable Al. The ET8 seedlings accumulated more Al in their apoplast than the ES8 seedlings. This study concluded that accumulation of Al in the apoplast is also involved in Al tolerance mechanism with the addition of organic acid exudation.

  1. Information of “Nukhbat al-dahr fi ‘aja’ib al-barr wa-al-bahr” by ad-Dimashqi about the Turkic Tribes of Dasht-i Kipchak »

    Directory of Open Access Journals (Sweden)

    Z.S. Ilyasova

    2016-12-01

    Full Text Available This article introduced into academic circulation information of such a historical source as “Nukhbat al-dahr fi ‘aja’ib al-barr wa-al-bahr” (Excerpts of Time on the Marvels of the Land and Sea on Kipchak clans and Turkic tribes of Dasht-i Kipchak. The material of the study is drawn from this source. Main scientific result of this work was the source’s translation into Russian accompanied by scientific comments. Sheikh Shams al-Din Abu Abdallah Muhammad Abu Talib al-Ansari al-Sufi al-Dimashqi was the author of this work. Some scholars have mistakenly confuse him with another chronicler named Shihab al-Din Ahmad ibn Yahya Ibn Fadlallah al-Omari al-Dimashqi. There is a widespread misconception that while writing on Kipchak clans and Turkic tribes al-Dimashqi used the data of such an author as Muhammad ibn Ibrahim ibn Yahya al-Ansari al-Qutub al-Warraq al-Vatvat, also known as Ahmad al-Tini. After had studying the manuscripts of al-Tini and al-Dimashqi, we did not notice the connection between these two authors regarding their information about Kipchak clans and Turkic tribes of Dasht-i Kipchak. After had studying the information about Kipchak clans and Turkic tribes of Dasht-i Kipchak, we put forward the theory that 16 ethnonyms previously identified as Kipchak clans, are actually the etnonyms of eight Kipchak clans and eight Turkic tribes. The article also contains the extraction from “Nukhbat al-dahr fi ‘aja’ib al-barr wa-al-bahr” regarding the geography of Dasht-i Kipchak and the countries inhabited by the Turks. The following data are unique in this source: 1. The text describes such rivers as Ceyhun (Amu Darya, Seyhun (Syr Darya, Itil (Volga, as well as Khorezm and Khazar Seas (Aral and Caspian Seas. 2. Additionally, this text lists the following Turkic peoples: al-Kharlukhiya (Karluks, al-Khirgaziya (Kyrgyz, al-Kaymakiya (Kimaks, al-Guzziya (Oguz, al-Bazhanakiya (Pechenegs, al-Tuguzguziya (Uighurs, al-Khulkhiya (?, al

  2. Studies on SiC(p) reinforced Al-Al sub 3 Ni eutectic matrix composites

    International Nuclear Information System (INIS)

    Masrom, A.K.; Foo, L.C.; Ismail, A.B.

    1996-01-01

    An investigation on processing of Al-5.69wt% Ni eutectic with SiC particulate composites is reported. The intermetallic composites are prepared by elemental powder metallurgy route and sintered at two different temperatures, i.e., 600 degree C and 620 degree C. Results show that the metal matrix was Al-Al sub 3 Ni eutectic. The phase analysis by XRD identified the presence of Al sub 3 Ni and Al as dominant phases together with silicon and Al sub 4 C sub 3 phase as minor phases. The Al sub 4 C sub 3 and Si phases are formed during sintering due to SiC-Al interface reaction. SEM micrographs also reveal the formation of microvoid surrounding the SiC particle

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

    Energy Technology Data Exchange (ETDEWEB)

    Markoli, B.; Spaic, S. [Ljubljana Univ. (Slovenia). Faculty of Natural Science and Engineering; Zupanic, F. [Maribor Univ. (Slovenia). Faculty of Mechanical Engineering

    2001-09-01

    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 ({alpha}{sub Al}, {beta}{sub Si}, Al{sub 3}Sm, Al{sub 2}Si{sub 2}Sm and AlSiSm) with following characteristic invariant reaction sequences: ternary eutectic reaction L {yields} {alpha}{sub Al} + {beta}{sub Si} + Al{sub 2}Si{sub 2}Sm, and two liquidus transition reactions, i. e., L + Al{sub 3}Sm {yields} {alpha}{sub Al} + AlSiSm, and L + AlSiSm {yields} {alpha}{sub Al} + Al{sub 2}Si{sub 2}Sm. 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.)

  4. Electronic Structures and Bonding Properties of Ti2AlC and Ti3AlC2

    Institute of Scientific and Technical Information of China (English)

    MIN Xinmin; REN Yi

    2007-01-01

    The relation among electronic structure, chemical bond and property of Ti2AlC, Ti3AlC2 and doping Si into Ti2AlC was studied by density function and the discrete variation (DFT-DVM) method. After adding Si into Ti2AlC, the interaction between Si and Ti is weaker than that between Al and Ti, and the strengths of ionic and covalent bonds decrease both. The ionic and covalent bonds in Ti3AlC2, especially in Ti-Al, are stronger than those in Ti2AlC. Therefore, in synthesis of Ti2AlC, the addition of Si enhances the Ti3AlC2 content instead of Ti2AlC. The density of state (DOS) shows that there is mixed conductor characteristic in Ti2AlC and Ti3AlC2. The DOS of Ti3AlC2 is much like that of Ti2AlC. Ti2SixAl1-x C has more obvious tendency to form a semiconductor than Ti2AlC, which is seen from the obvious difference of partial DOS between Si and Al3p.

  5. 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.

  6. Deletion of ALS5, ALS6 or ALS7 increases adhesion of Candida albicans to human vascular endothelial and buccal epithelial cells

    OpenAIRE

    ZHAO, XIAOMIN; OH, SOON-HWAN; HOYER, LOIS L.

    2007-01-01

    C. albicans yeast forms deleted for ALS5, ALS6 or ALS7 are more adherent than a relevant control strain to human vascular endothelial cell monolayers and buccal epithelial cells. In the buccal and vaginal reconstituted human epithelium (RHE) disease models, however, mutant and control strains caused a similar degree of tissue destruction. Deletion of ALS5 or ALS6 significantly slowed growth of the mutant strain; this phenotype was not affected by addition of excess uridine to the culture medi...

  7. Alpha and beta stabilizer character of Al in Zr-Nb-Al alloys

    International Nuclear Information System (INIS)

    Peruzzi Bardella, A.; Bolcich, J.C.

    1987-01-01

    The T β/α+β of Zr5Nb and Zr5Nb2Al (weight %) were determined in order to observe the alpha-stabilizer character of Al in ternary Zr-Nb-Al alloys. Techniques employed were change of resistivity with temperature in dynamic experiences, and metallography of samples quenched to room temperature after isothermal annealings. The T β/α+β of the ternary resulted 17 ± 8 deg C higher than that of the binary alloy. In addition, taking into account the results of previous investigations of the transformation of beta on quenching Zr-Nb-Al alloys from the beta field to room temperature, it is concluded that the beta-stabilizer character of Nb is stronger than the alpha-stabilizer character of Al in these Zr alloys, and that the Al can have important influence on the mechanical properties by the appearance of TRIP effect. (Author) [es

  8. Insulator-semiconductor interface fixed charges in AlGaN/GaN metal-insulator-semiconductor devices with Al2O3 or AlTiO gate dielectrics

    Science.gov (United States)

    Le, Son Phuong; Nguyen, Duong Dai; Suzuki, Toshi-kazu

    2018-01-01

    We have investigated insulator-semiconductor interface fixed charges in AlGaN/GaN metal-insulator-semiconductor (MIS) devices with Al2O3 or AlTiO (an alloy of Al2O3 and TiO2) gate dielectrics obtained by atomic layer deposition on AlGaN. Analyzing insulator-thickness dependences of threshold voltages for the MIS devices, we evaluated positive interface fixed charges, whose density at the AlTiO/AlGaN interface is significantly lower than that at the Al2O3/AlGaN interface. This and a higher dielectric constant of AlTiO lead to rather shallower threshold voltages for the AlTiO gate dielectric than for Al2O3. The lower interface fixed charge density also leads to the fact that the two-dimensional electron concentration is a decreasing function of the insulator thickness for AlTiO, whereas being an increasing function for Al2O3. Moreover, we discuss the relationship between the interface fixed charges and interface states. From the conductance method, it is shown that the interface state densities are very similar at the Al2O3/AlGaN and AlTiO/AlGaN interfaces. Therefore, we consider that the lower AlTiO/AlGaN interface fixed charge density is not owing to electrons trapped at deep interface states compensating the positive fixed charges and can be attributed to a lower density of oxygen-related interface donors.

  9. 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.

  10. Effects of Al(III) and nano-Al13 species on malate dehydrogenase activity.

    Science.gov (United States)

    Yang, Xiaodi; Cai, Ling; Peng, Yu; Li, Huihui; Chen, Rong Fu; Shen, Ren Fang

    2011-01-01

    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 Al(13) can activate the enzymatic activity of MDH, and the activation reaches maximum levels as the Al(III) and Al(13) concentration increase. Our study also found that the effects of Al(III) and Al(13) 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.

  11. Fracture toughness of Ti-Al3Ti-Al-Al3Ti laminate composites under static and cyclic loading conditions

    Science.gov (United States)

    Patselov, A. M.; Gladkovskii, S. V.; Lavrikov, R. D.; Kamantsev, I. S.

    2015-10-01

    The static and cyclic fracture toughnesses of a Ti-Al3Ti-Al-Al3Ti laminate composite material containing at most 15 vol % intermetallic compound are studied. Composite specimens are prepared by terminating reaction sintering of titanium and aluminum foils under pressure. The fracture of the titanium layers is quasi-cleavage during cyclic crack growth and is ductile during subsequent static loading.

  12. 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...

  13. Ti, Al

    Indian Academy of Sciences (India)

    In the present study, authors report on the effect that substrate bias voltage has on the microstructure and mechanical properties of (Ti, Al)N hard coatings deposited with cathodic arc evaporation (CAE) technique. The coatings were deposited from a Ti0.5Al0.5 powder metallurgical target in a reactive nitrogen atmosphere at ...

  14. 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)

  15. First-principles study of L10 Ti-Al and V-Al alloys

    International Nuclear Information System (INIS)

    Chubb, S.R.; Papaconstantopoulos, D.A.; Klein, B.M.

    1988-01-01

    As a first step towards understanding the reduced embrittlement of L1 0 Ti-Al alloys which accompanies the introduction of small concentrations of V, we have determined from first principles, using full-potential linearized--augmented-plane-wave calculations, the equilibrium values of the structural parameters and the associated electronic structure for the stoichiometric (L1 0 ) Ti-Al (tetragonal) compound. Our calculated values of c/a and a are in good agreement with experiment. Using the same method of calculation, we have also studied the electronic structure associated with the (hypothetical) L1 0 V-Al alloy that would form when V is substituted for Ti. We find that (1) the electronic structures of these V-Al alloys are relatively insensitive to variations of c/a and a; (2) near the Ti-Al equilibrium geometry, the electronic structures of the V-Al and Ti-Al alloys are very similar; and (3) that a rigid-band model involving substitution of V for Ti can be used to gain a qualitative understanding of the reduction in c/a which accompanies the introduction of small concentrations of V. We relate the reduction in c/a to important changes in the bonding that accompany the occupation of bands immediately above the Fermi level of the stoichiometric Ti-Al compound

  16. Kinetic studies of oxidation of MgAlON and a comparison of the oxidation behaviour of AlON, MgAlON, O'SiAlON-ZrO{sub 2}, and BN-ZCM ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Wang Xidong; Seetharaman, S. [Div. of Metallurgy, Royal Inst. of Tech., Stockholm (Sweden); Li Wenchao [Dept. of Physical Chemistry, Univ. of Science and Technology Beijing (USTB), Beijing, BJ (China)

    2002-06-01

    The kinetics and morphology of the oxidation process of magnesium-aluminium oxynitride (MgAlON), aluminium oxynitride (AlON), O'SiAlON-ZrO{sub 2}, and BN-ZCM have been studied in the temperature range 1373-1773 K (ZCM=30 wt% ZrO{sub 2}, 52 wt% Al{sub 2}O{sub 3} and 18 wt% 3 Al{sub 2}O{sub 3}.2 SiO{sub 2}). Oxidation experiments with powder and plate samples of the above materials have been carried out in air. MgAlON shows the best resistance to oxidation at lower temperatures (< 1473 K), whereas at higher temperatures ({proportional_to} 773 K), AlON shows the best resistance. O'SiAlON-ZrO{sub 2} shows very good oxidation resistance up to 1673 K. But its oxidation rate increases strongly above 1673 K, presumably due to the formation of liquid phase. BN-ZCM has the poorest oxidation resistance due to the evaporation of B{sub 2}O{sub 3}. The activation energies for the chemical oxidation reaction of AlON, MgAlON, and O'SiAlON-ZrO{sub 2} are 214, 330 and 260 kJ/mol, respectively. The overall diffusion activation energies for AlON, MgAlON, O'SiAlON-ZrO{sub 2} and BN-ZCM are 227, 573, 367 and 289 kJ/mol, respectively. (orig.)

  17. Grain refining mechanism of Al-containing Mg alloys with the addition of Mn-Al alloys

    International Nuclear Information System (INIS)

    Qin, Gaowu W.; Ren Yuping; Huang Wei; Li Song; Pei Wenli

    2010-01-01

    Graphical abstract: Display Omitted Research highlights: The ε-AlMn phase acts as the heterogeneous nucleus of α-Mg phase during the solidification of the AZ31 Mg alloy, not the γ-Al 8 Mn 5 phase. The grain refinement effect is very clear with the addition of only 0.5 wt% Mn-28Al alloy (pure ε-AlMn). The grain refinement does not deteriorate up to the holding time of 60 min at 740 o C. - Abstract: The effect of manganese on grain refinement of Al-containing AZ31 Mg alloy has been investigated by designing a series of Mn-Al alloys composed of either pure ε-AlMn, γ 2 -Al 8 Mn 5 or both of them using optical microscopy and X-ray diffraction. It is experimentally clarified that the grain refinement of the AZ31 Mg alloy is due to the existence of the ε-AlMn phase in the Mn-Al alloys, not the γ 2 -Al 8 Mn 5 phase. The grain size of AZ31 Mg alloy is about 91 μm without any addition of Mn-Al alloys, but remarkably decreases to ∼55 μm with the addition of either Mn-34 wt% Al or Mn-28 wt% Al. With a minor addition of 0.5 wt% Mn-28Al alloy, the grain size of AZ31 alloy decreases to ∼53 μm, and the Mn-28Al alloy can be active as grain refiner for holding time up to 60 min for the melt AZ31 alloy at 750 o C.

  18. Ibn Qutayba en al-Andalus. La préface à I 'Adab al-Kātib dans le commentaire d'Ibn al-Sīd al-Baṭalyawsī

    Directory of Open Access Journals (Sweden)

    Soravia, Bruna

    2004-12-01

    Full Text Available Ibn Qutayba's preface to his Adab al-kātib has been considered for centuries the most important section of this work and it has been the object of many commentaries, both in the Muslim East and West. This paper deals with Ibn al-Sīd al-Baṭalyawsī´s commentary al-Iqtiḍāb, trying to show the peculiar way in which Ibn al-Sīd develops his own critique of Ibn Qutayba's controversial thesis on the relation between orthodoxy, falsafa and kalām. At the same time, the Andalusi author works out his own conception of adab, deeply influenced by his biographical experience. Finally a full translation of Ibn Qutayba's preface is proposed, half a century after G. Lecomte's partial one.

    El prefacio de Ibn Qutayba a su Adab al-Kātib ha sido considerado durante siglos como el fragmento más importante de su obra, y ha sido objeto de muchos comentarios, tanto orientales como occidentales. Este artículo trata del comentario que Ibn al-Sīd al-Baṭalyawsī hizo de ese texto de Ibn Qutayba, e intenta mostrar la forma peculiar en que Ibn al-Sīd desarrolla su propia crítica a la polémica tesis de Ibn Qutayba sobre la relación entre ortodoxia, falsafa y kalām. Al mismo tiempo, el autor andalusí elabora su propia concepción del adab, profundamente influida por su experiencia biográfica. Para concluir, se presenta una traducción completa del prefacio de Ibn Qutayba, medio siglo después de la parcial realizada por G. Lecomte.

  19. Interview als Text vs. Interview als Interaktion

    Directory of Open Access Journals (Sweden)

    Arnulf Deppermann

    2013-09-01

    Full Text Available Das Interview ist nach wie vor das beliebteste sozialwissenschaftliche Verfahren des Datengewinns. Ökonomie der Erhebung, Vergleichbarkeit und die Möglichkeit, Einsicht in Praxisbereiche und historisch-biografische Dimensionen zu erhalten, die der direkten Beobachtung kaum zugänglich sind, machen seine Attraktivität aus. Zugleich mehren sich Kritiken, die seine Leistungsfähigkeit problematisieren, indem sie auf die begrenzte Reichweite der Explikationsfähigkeiten der Befragten, die Reaktivität der Erhebung oder die Differenz zwischen Handeln und dem Bericht über Handeln verweisen. Im Beitrag wird zwischen Ansätzen, die das Interview als Text, und solchen, die es als Interaktion verstehen, unterschieden. Nach dem Text-Verständnis werden Interviews unter inhaltlichen Gesichtspunkten analysiert und als Zugang zu einer vorgängigen sozialen oder psychischen Wirklichkeit angesehen. Das Interaktions-Verständnis versteht Interviews dagegen als situierte Praxis, in welcher im Hier und Jetzt von InterviewerInnen und Befragten gemeinsam soziale Sinnstrukturen hergestellt werden. Anhand ubiquitärer Phänomene der Interviewinteraktion – Fragen, Antworten und die Selbstpositionierung von InterviewerInnen und Befragten – werden Praktiken des interaktiv-performativen Handelns im Interview dargestellt. Ihre Relevanz für die Interviewkonstitution und ihre Erkenntnispotenziale für die Interviewauswertung werden aufgezeigt. Es wird dafür plädiert, die interaktive Konstitutionsweise von Interviews empirisch zu erforschen und methodisch konsequent zu berücksichtigen. URN: http://nbn-resolving.de/urn:nbn:de:0114-fqs1303131

  20. Structure and phase composition of Al-Ce-Cu system alloys in range of quasi-binary Al-Al8CeCu4 section

    International Nuclear Information System (INIS)

    Belov, N.A.; Khvan, A.V.

    2007-01-01

    The phase diagram of the Al-Cu-Ce system in the quasibinary section area of Al-Al 8 CeCu 4 has been investigated by metallographic, thermal, micro-X-ray spectral and X-ray structural analyses. The parameters of the eutectic reaction L→(Al)+CeCu 4 Al 8 : T=610 Deg C were found out; the composition was 14% Cu and 7% Ce. This eutectics is of a disperse structure and the ternary compound contained is capable of fragmentation and spheroidizing in the heating process (starting from 540 Deg C). It was demonstrated that the area of optimal (Al)+CeCu 4 Al 8 eutectics-based alloy compositions was within the narrow limits. That is related to the fact that at a comparatively little variation of the Cu:Ce=2 ratio solidus sharply decreases and, as a result, the crystallization interval considerably extends [ru

  1. Structural and electrical characterization of AuPtAlTi ohmic contacts to AlGaN/GaN with varying annealing temperature and Al content

    OpenAIRE

    Fay, Mike W.; Han, Y.; Brown, Paul D.; Harrison, Ian; Hilton, K.P.; Munday, A.; Wallis, D.; Balmer, R.S.; Uren, M.J.; Martin, T.

    2008-01-01

    The effect of varying annealing temperature and Al layer thickness on the structural and electrical characteristics of AuPtAlTi/AlGaN/GaN ohmic contact structures has been systematically investigated. The relationship between annealing temperature, Al content, interfacial microstructure, surface planarity and contact resistance is\\ud examined. In particular, the presence of a detrimental low temperature Pt-Al reaction is identified. This is implicated in both the requirement for a higher Al:T...

  2. Grain refining mechanism of Al-containing Mg alloys with the addition of Mn-Al alloys

    Energy Technology Data Exchange (ETDEWEB)

    Qin, Gaowu W., E-mail: qingw@smm.neu.edu.c [Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education), Northeastern University, Wenhu Road 3-11, Heping District, Shenyang 110004, Liaoning Province (China); Ren Yuping; Huang Wei; Li Song; Pei Wenli [Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education), Northeastern University, Wenhu Road 3-11, Heping District, Shenyang 110004, Liaoning Province (China)

    2010-10-08

    Graphical abstract: Display Omitted Research highlights: The {epsilon}-AlMn phase acts as the heterogeneous nucleus of {alpha}-Mg phase during the solidification of the AZ31 Mg alloy, not the {gamma}-Al{sub 8}Mn{sub 5} phase. The grain refinement effect is very clear with the addition of only 0.5 wt% Mn-28Al alloy (pure {epsilon}-AlMn). The grain refinement does not deteriorate up to the holding time of 60 min at 740 {sup o}C. - Abstract: The effect of manganese on grain refinement of Al-containing AZ31 Mg alloy has been investigated by designing a series of Mn-Al alloys composed of either pure {epsilon}-AlMn, {gamma}{sub 2}-Al{sub 8}Mn{sub 5} or both of them using optical microscopy and X-ray diffraction. It is experimentally clarified that the grain refinement of the AZ31 Mg alloy is due to the existence of the {epsilon}-AlMn phase in the Mn-Al alloys, not the {gamma}{sub 2}-Al{sub 8}Mn{sub 5} phase. The grain size of AZ31 Mg alloy is about 91 {mu}m without any addition of Mn-Al alloys, but remarkably decreases to {approx}55 {mu}m with the addition of either Mn-34 wt% Al or Mn-28 wt% Al. With a minor addition of 0.5 wt% Mn-28Al alloy, the grain size of AZ31 alloy decreases to {approx}53 {mu}m, and the Mn-28Al alloy can be active as grain refiner for holding time up to 60 min for the melt AZ31 alloy at 750 {sup o}C.

  3. AYAT-AYAT WAH}DAT AL-WUJUd dalam Kitab Tanbi>h al-Ma>shi Karya ‘Abdurrauf al-Sinkili

    Directory of Open Access Journals (Sweden)

    Asep Nahrul Musadad

    2015-08-01

    Full Text Available Abstract: One of the key moments in discussing the history of Indonesian Islam is a polemic related to the negotiation on the doctrine of wahdat al-wujud that occured in Aceh in 17th century between the followers of Hamzah al-Fansuri and Nuruddin al-Raniri. This article focuses on analyzing several Qur’anic verses used by ‘Abdurrauf as the confirmation of his argument. In the polemical context, Abdurrauf al-Sinkili appeared to be an actor of reconciliation between two opposite sides. He tried to respond to the disputed issues through his book called “Tanbi>h al-Mashi”. As an exponent of the so-called moderate sufism (mysticism, he built the argument concerning wah}dat al-wujud based on the Quranic text. After making a thematic classification chronologically, his interpretation on these verses is analyzed by using Hussain al-Dhahaby’s theory of sufistic exegesis. In conclusion, it shows that ‘Abdurrauf’s commentary is “sufi-nazari type”, featured by his exegeses pattern. This, of course, represents his attitude as a reconciler who then needs to seek confirmation to the Qur’anic verses in evaluating wah}dat al-wujud doctrine, through which such a polemical issues occurred at that time. الملخص: إن من المرحلة الأساسية التي مرّ بها تاريخ الإسلام في اندونيسيا الجدل و النزاع حول عقيدة وحدة الوجود فى أتشيه (Aceh حول قرن السابع عشر بين أتباع حمزة الفنسوري و نور الدين الرانيري. ففي ذلك الخطاب النزاعي جاء عبد الرؤوف السنكيلي مصلحا بين الجانبين المعاكسين. وعلى مقتضى الظروف، كتب كتاب " تنبيه الماشي" الذي تطرّق فيه طريق التوسّط، ممثّلا للتصوّف المعتدل. اعتمد عبد الرؤوف على النصوص القرآنية فى تحقيق آراءه حول ت

  4. Reviewing Medical Education in KamelAl-Senaat Al-Tebieh

    Directory of Open Access Journals (Sweden)

    Shahla Moradi

    2017-06-01

    Full Text Available Background and Objective: Among the human sciences, medicine is superior to all other sciences. One of the effective factors in education, especially in medical education is using appropriate textbooks. This study aims to consider a classic book of medical education and find its relevance to modern medicine. Materials and Methods: Reviewing and analyzing parts of Kamel Al-Senaat Al-Tebieh medical textbook. Results: This book has about four hundred thousand words and it was divided into twenty articles, each consisting of several chapters, first ten topics of which are about theoretical medicine, and others are information related to practical medicine. Conclusion: One of the most important obligations of every nation is to protect and preserve written and unwritten cultural and scientific resources Kamel Al-Senaat Al-Tebieh was written in one of the glorious periods of Iranian Medical History by Ali Ibn Abbas. It has a dignified position because of its recording method. This method is one of the best methods that is used after Ahvazi. Even today it is a valuable source of medical education.

  5. Density and atomic volume in liquid Al-Fe and Al-Ni binary alloys

    Energy Technology Data Exchange (ETDEWEB)

    Plevachuk, Yu. [Ivan Franko National Univ., Lviv (Ukraine). Dept. of Metal Physics; Egry, I.; Brillo, J.; Holland-Moritz, D. [Deutsches Zentrum fuer Luft- und Raumfahrt, Koeln (Germany). Inst. fuer Raumsimulation; Kaban, I. [Chemnitz Univ. of Technolgy (Germany). Inst. of Physics

    2007-02-15

    The density of liquid Al-Fe and Al-Ni binary alloys have been determined over a wide temperature range by a noncontact technique combining electromagnetic levitation and optical dilatometry. The temperature and composition dependences of the density are analysed. A negative excess volume correlates with the negative enthalpy of mixing, compound forming ability and chemical short-range ordering in liquid Al-Fe and Al-Ni alloys. (orig.)

  6. TEM characterization of Al-C-Cu-Al2O3 composites produced by mechanical milling

    International Nuclear Information System (INIS)

    Santos-Beltran, A.; Gallegos-Orozco, V.; Estrada-Guel, I.; Bejar-Gomez, L.; Espinosa-Magana, F.; Miki-Yoshida, M.; Martinez-Sanchez, R.

    2007-01-01

    Novel Al-based composites (Al-C-Cu-Al 2 O 3 ) obtained by mechanical milling (MM), were characterized by transmission electron microscopy (TEM) and electron energy loss spectroscopy (EELS). Analyses of composites were carried out in both, the as-milled and the as-sintered conditions. C nanoparticles were found in the as-milled condition and Al 2 O 3 nanofibers were found in as-sintered products, as determined by EELS. C and Cu react with Al to crystallize in Al 3 C 4 and Al 2 Cu structures, respectively

  7. Formation of AlFeSi phase in AlSi12 alloy with Ce addition

    Directory of Open Access Journals (Sweden)

    S. Kores

    2012-04-01

    Full Text Available The influence of cerium addition on the solidification sequence and microstructure constituents of the Al-Si alloys with 12,6 mass % Si was examined. The solidification was analyzed by a simple thermal analysis. The microstructures were examined with conventional light and scanning electron microscopy. Ternary AlSiCe phase was formed in the Al-Si alloys with added cerium during the solidification process. AlSiCe and β-AlFeSi phases solidified together in the region that solidified the last. Cerium addition influenced on the morphology of the α-AlFeSi phase solidification.

  8. Compressive performance and crack propagation in Al alloy/Ti{sub 2}AlC composites

    Energy Technology Data Exchange (ETDEWEB)

    Hanaor, D.A.H., E-mail: dorian.hanaor@sydney.edu.au [School of Civil Engineering, University of Sydney, Sydney, NSW 2006 (Australia); Hu, L. [Ames Laboratory, U.S. Department of Energy, Ames, Iowa 50011 (United States); Kan, W.H.; Proust, G. [School of Civil Engineering, University of Sydney, Sydney, NSW 2006 (Australia); Foley, M. [Australian Centre for Microscopy and Microanalysis, University of Sydney, Sydney, NSW 2006 (Australia); Karaman, I.; Radovic, M. [Department of Materials Science and Engineering, Texas A& M University, College Station, TX 77843 (United States)

    2016-08-30

    Composite materials comprising a porous Ti{sub 2}AlC matrix and Al 6061 alloy were fabricated by a current-activated pressure assisted melt infiltration process. Coarse, medium and fine meso-structures were prepared with Al alloy filled pores of differing sizes. Materials were subjected to uniaxial compressive loading up to stresses of 668 MPa, leading to the failure of specimens through crack propagation in both phases. As-fabricated and post-failure specimens were analysed by X-ray microscopy and electron microscopy. Quasi-static mechanical testing results revealed that compressive strength was the highest in the fine structured composite materials. While the coarse structured specimens exhibited a compressive strength of 80% relative to this. Reconstructed micro-scale X-ray tomography data revealed different crack propagation mechanisms. Large planar shear cracks propagated throughout the fine structured materials while the coarser specimens exhibited networks of branching cracks propagating preferentially along Al alloy-Ti{sub 2}AlC phase interfaces and through shrinkage pores in the Al alloy phase. Results suggest that control of porosity, compensation for Al alloy shrinkage and enhancement of the Al alloy-Ti{sub 2}AlC phase interfaces are key considerations in the design of high performance metal/Ti{sub 2}AlC phase composites.

  9. Phase equilibria and crystalline structure of compounds in the Lu-Al and Lu-Cu-Al systems

    International Nuclear Information System (INIS)

    Kuz'ma, Yu.B.; Stel'makhovich, B.M.; Galamushka, L.I.

    1992-01-01

    Phase equilibria and crystal structure of compounds in Lu-Al and Lu-Cu-Al systems were studied. Existence of Lu 2 Al compound having the structure of the PbCl 2 type is ascertained. Diagram of phase equilibria of Lu-Cu-Al system at 870 K is plotted. Compounds Lu 2 (Cu,Al) 17 (the Th 2 Zn 17 type structure), Lu(Cu,Al) 5 (CaCu 5 type structure), Lu 6 (Cu,Al) 23 (Th 6 Mn 23 type structure) and ∼ LuCuAl 2 have been prepared for the first time. Investigation of component interaction in Lu-Cu-Al system shows that the system is similar to previously studied systems Dy-Cu-Al and Er-Cu-Al. The main difference consists in the absence of LuCuAl 3 compound with rhombic structure of the CeNi 2+x Sb 2-x type in the system investigated

  10. 1131-IJBCS-Article-Kouame Guy M Bouafou

    African Journals Online (AJOL)

    DR GATSING

    nutriments sur la base de 4 kcal pour 1 g de protéine, 4 kcal pour 1 g de glucide et 9 kcal pour 1 g de lipide. ... rénal. (Balasubramaiam, 2003). Le rapport normal Ca/P plasmatique est l'indice d'un .... Acido-basiques et Hydroélectrolytiques,.

  11. Al Qaeda in the Arabian Peninsula (AQAP): An Al Qaeda Affiliate Case Study

    Science.gov (United States)

    2017-10-01

    Villarosa, Al-Qaeda in Yemen, Carnegie Endowment, July 7, 2009, http://carnegieendowment.org/2009/07/07/Al-Qaeda-in-yemen- event-1372. 53 Brian Whitaker...73 Khaled Fattah, “Yemen’s Insecurity Dilemma,” Yemen Times, February 11, 2014, http:// carnegie -mec.org/2014/02...Johnsen, and Shari Villarosa, “Al-Qaeda in Yemen.” Carnegie Endowment. July 7, 2009. http://carnegieendowment.org/2009/07/07/Al-Qaeda-in- yemen-event

  12. Formation of epitaxial Al 2O 3/NiAl(1 1 0) films: aluminium deposition

    Science.gov (United States)

    Lykhach, Y.; Moroz, V.; Yoshitake, M.

    2005-02-01

    Structure of epitaxial Al 2O 3 layers formed on NiAl(1 1 0) substrates has been studied by means of reflection high-energy electron diffraction (RHEED). The elucidated structure was compared to the model suggested for 0.5 nm-thick Al 2O 3 layers [K. Müller, H. Lindner, D.M. Zehner, G. Ownby, Verh. Dtsch. Phys. Ges. 25 (1990) 1130; R.M. Jaeger, H. Kuhlenbeck, H.J. Freund, Surf. Sci. 259 (1991) 235]. The stepwise growth of Al 2O 3 film, involving deposition and subsequent oxidation of aluminium onto epitaxial 0.5 nm-thick Al 2O 3 layers, has been investigated. Aluminium was deposited at room temperature, whereas its oxidation took place during annealing at 1070 K. The Al 2O 3 thickness was monitored by means of Auger electron spectroscopy (AES). It was found that Al 2O 3 layer follows the structure of 0.5 nm thick Al 2O 3 film, although a tilting of Al 2O 3(1 1 1) surface plane with respect to NiAl(1 1 0) surface appeared after Al deposition.

  13. Amyotrophic lateral sclerosis (ALS)

    Science.gov (United States)

    Lou Gehrig disease; ALS; Upper and lower motor neuron disease; Motor neuron disease ... One out of 10 cases of ALS is due to a genetic defect. The cause is unknown in most other cases. In ALS, motor nerve cells (neurons) waste away ...

  14. Pemikiran Politik al-Shawkânî dalam Fath al-Qadîr

    Directory of Open Access Journals (Sweden)

    Yusuf Hanafi

    2015-09-01

    Full Text Available Muhammad b. ‘Alî Muhammad b. ‘Abd Allâh al-Shawkânî al-San‘ânî. He was born in the Hijrah in Shawkân village, Yemen on Monday 28 Dhû al-Qa‘dah 1172 H and died on Tuesday, 27 Jumâd al-Akhîr 1250 H at the age about 78 years. Al-Shawkânî grew up in the San‘a city, it is the capital of the republic of Yemen now. He study first time about religion from his father, then from renowed scholars in San‘a and its surrounding, he was known as a scolar who mastered the various branches of religious sciences. Such as tafsîr, h}adîth, fiqh, us}ûl al-fiqh, history, science of kalâm, philosophy, balâghah, mant}iq etc. the main issue in this article is how political thought in the book of tafsir Fath al-Qadîr is the work of Shawkânî. At the end of article, the authors found that the intended political thinking in the study of Fath al-Qadîr is about constitutional ideas. These ideas about the constitution is limited to the concept of leadership and deliberation, the concept of the right of citizen to obtain justice, and the concept pf the right of citizens to live association and assembly

  15. Oxidation behavior of Al/Cr coating on Ti2AlNb alloy at 900 °C

    Science.gov (United States)

    Yang, Zhengang; Liang, Wenping; Miao, Qiang; Chen, Bowen; Ding, Zheng; Roy, Nipon

    2018-04-01

    In this paper, the Al/Cr coating was fabricated on the surface of Ti2AlNb alloy via rf magnetron sputtering and double glow treatment to enhance oxidation resistance. The protective coating with an outer layer of Al and inner layer of Cr has great bonding strength due to the in-diffusion of Cr and the inter-diffusion between Al and Cr to form Al-Cr alloyed layer which has great hardness. Acoustic emission curve which was detected via WS-2005 scratch tester indicates the bonding strength between Al/Cr coating and substrate is great. Morphology of Ti2AlNb alloy with Al/Cr coating after scratch test shows that the scratch is smooth without disbanding, and the depth and breadth of scratch are changed uniformly. The mass change was reduced after oxidation test due to the Al/Cr protective coating. Isothermal oxidation test at 900 °C was researched. Results indicate that Al/Cr coating provided oxidation resistance of Ti2AlNb alloy with prolonged air exposure at 900 °C. Al2O3 was detected by XRD patterns and SEM images, and was formed on the surface of Ti2AlNb alloy to protect substrate during oxidation test. A certain content of Cr is beneficial for the formation of Al2O3. Besides, Cr2O3 was produced under Al2O3 by outward diffusion of Cr to protect substrate sequentially, no cracks were discovered on Al/Cr protective coating. The process of Ti outward diffusion into surface was suppressive due to integration of Cr-Ti and Al-Ti intermetallics. A steady, adherent and continuous coated layer of Al/Cr on Ti2AlNb alloy increases oxidation resistance.

  16. ¿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.

  17. Investigation of annealing treatment on the interfacial properties of explosive-welded Al/Cu/Al multilayer

    International Nuclear Information System (INIS)

    Honarpisheh, M.; Asemabadi, M.; Sedighi, M.

    2012-01-01

    Highlights: ► We studied explosive-welded Al/Cu/Al multilayer. ► We investigated heat treatment influence on the bond properties of Al/Cu/Al. ► Intermetallic compounds were studied using the SEM, OM and EDS analysis. ► Variations of hardness in the thickness were investigated using micro-hardness. ► Intermetallic phases such as AlCu 3 and Al 2 C create at the interface of Al/Cu/Al. -- Abstract: In this study, an Al/Cu/Al multilayer sheet was fabricated by explosive welding process and the effects of annealing temperature on the interfacial properties of explosively bonded Al/Cu bimetal have been investigated. For this purpose, hardness changes along the thickness of the samples have been measured, and the thickness and type of intermetallic compounds formed at the joining interface have been explored by means of optical microscopy (OM), scanning electron microscopy (SEM) and also energy dispersive spectroscopy (EDS). The obtained results indicate that, with the increase of the annealing temperature, the thickness of intermetallic compounds has increased and the amount of hardness along the thickness of the joining interface has diminished. In the annealed sample at 400 °C for 30 min, it was observed that intermetallic layers have formed at the interface of Al/Cu bimetals. These layers consist of the intermetallic compounds AlCu 3 , Al 2 Cu and AlCu, and their thickness gets to about 5 μm at some points. The examinations performed by the SEM, following the Vickers micro-hardness test, indicated the existence of a number of microcracks at the top and bottom interface of the sample annealed at 400 °C. This shows the formation of brittle intermetallic compounds at the joining interface, and also indicates the low ductility of these compounds.

  18. NMR evidence for Co-Al-Co molecular groups trapped in cages of Co4Al13

    International Nuclear Information System (INIS)

    Jeglic, P.; Heggen, M.; Feuerbacher, M.; Bauer, B.; Gille, P.; Haarmann, F.

    2009-01-01

    We present the results of 27 Al nuclear magnetic resonance (NMR) experiments on the phase Co 4 Al 13 . These results are compared to a recent structure model [1], which demonstrates a unique bonding for Al atoms in the Co-Al-Co molecular groups. In our measurement, two 27 Al signals were identified. The first one originates from Al atoms forming cages. The second signal corresponds to Al sites with exceptionally large almost axially symmetric quadrupole coupling. This finding is in perfect agreement with isolated Co-Al-Co molecular groups in accordance to Ref. [1].

  19. The Y-Cu-Al system

    International Nuclear Information System (INIS)

    Krachan, T.; Stel'makhovych, B.; Kuz'ma, Yu.

    2003-01-01

    The phase diagram of the Y-Cu-Al system at 820 K has been constructed using X-ray powder diffraction. The existence of earlier known ternary aluminides has been confirmed and their homogeneity regions and atomic distributions in the structures have been determined: YCu 4.6-4.0 Al 7.4-8.0 (ThMn 12 -type R I =0.049), Y 2 Cu 12.0-10.5 Al 5.0-6.5 (Th 2 Zn 17 -type R I =0.092), YCu 1.0-1.1 Al 1.0-0.9 (Fe 2 P-type R I =0.068). It has been shown that the structure of Y(Cu,Al) 3 is characterized by an ordered distribution of the Cu and Al atoms and it should be referred as Ca 3 Cu 2 Al 7 structure type (R I =0.060) besides the PuNi 3 structure type with statistical occupancies of the smaller atoms. At the investigated temperature the compound YCu 1.0-0.25 Al 3.0-3.75 (BaAl 4 -type) was not observed. However, we found the ternary aluminide with composition Y 3 Cu 2.7-2.0 Al 8.3-9.0 and related La 3 Al 11 -type (space group Immm, a=0.4192-0.4228, b=1.2423-1.2557, c=0.9812-0.9895 nm, R I =0.069). The compounds YCu 6.8 Al 4.2 (space group Fddd, Tb(Cu 0.58 Al 0.42 ) 11 -type, a=1.42755, b=1.48587, c=0.65654 nm, R I =0.062) and YCu 6.5 Al 4.5 (space group I4 1 /amd, BaCd 11 -type, a=1.02774, c=0.65838 nm, R I =0.071) have been found and structurally refined for the first time

  20. Preparation, deformation, and failure of functional Al-Sn and Al-Sn-Pb nanocrystalline alloys

    Science.gov (United States)

    Noskova, N. I.; Vil'Danova, N. F.; Filippov, Yu. I.; Churbaev, R. V.; Pereturina, I. A.; Korshunov, L. G.; Korznikov, A. V.

    2006-12-01

    Changes in the structure, hardness, mechanical properties, and friction coefficient of Al-30% Sn, Al-15% Sn-25% Pb, and Al-5% Sn-35% Pb (wt %) alloys subjected to severe plastic deformation by equal-channel angular pressing (with a force of 40 tonne) and by shear at a pressure of 5 GPa have been studied. The transition into the nanocrystalline state was shown to occur at different degrees of plastic deformation. The hardness exhibits nonmonotonic variations, namely, first it increases and subsequently decreases. The friction coefficient of the Al-30% Sn, Al-15% Sn-25% Pb, and Al-5% Sn-35% Pb alloys quenched from the melt was found to be 0.33; the friction coefficients of these alloys in the submicrocrystalline state (after equal-channel angular pressing) equal 0.24, 0.32, and 0.35, respectively. The effect of disintegration into nano-sized powders was found to occur in the Al-15% Sn-25% Pb, and Al-5% Sn-35% Pb alloys after severe plastic deformation to ɛ = 6.4 and subsequent short-time holding.

  1. Characterization of Al/Ni multilayers and their application in diffusion bonding of TiAl to TiC cermet

    International Nuclear Information System (INIS)

    Cao, J.; Song, X.G.; Wu, L.Z.; Qi, J.L.; Feng, J.C.

    2012-01-01

    The Al/Ni multilayers were characterized and diffusion bonding of TiAl intermetallics to TiC cermets was carried out using the multilayers. The microstructure of Al/Ni multilayers and TiAl/TiC cermet joint was investigated. The layered structures consisting of a Ni 3 (AlTi) layer, a Ni 2 AlTi layer, a (Ni,Al,Ti) layer and a Ni diffusion layer were observed from the interlayer to the TiAl substrate. Only one AlNi 3 layer formed at the multilayer/TiC cermet interface. The reaction behaviour of Al/Ni multilayers was characterized by means of differential scanning calorimeter (DSC) and X-ray diffraction. The initial exothermic peak of the DSC curve was formed due to the formation of Al 3 Ni and Al 3 Ni 2 phases. The reaction sequence of the Al/Ni multilayers was Al 3 Ni → Al 3 Ni 2 → AlNi → AlNi 3 and the final products were AlNi and AlNi 3 phases. The shear strength of the joint was tested and the experimental results suggested that the application of Al/Ni multilayers improved the joining quality. - Highlights: ► Diffusion bonding of TiAl to TiC cermet was realized using Al/Ni multilayer. ► The reaction sequence of the Al/Ni multilayers was Al 3 Ni → Al 3 Ni 2 → AlNi → AlNi 3 . ► The interfacial microstructure of the joint was clarified. ► The application of Al/Ni multilayers improved the joining quality.

  2. Hot Corrosion Behavior of Stainless Steel with Al-Si/Al-Si-Cr Coating

    Science.gov (United States)

    Fu, Guangyan; Wu, Yongzhao; Liu, Qun; Li, Rongguang; Su, Yong

    2017-03-01

    The 1Cr18Ni9Ti stainless steel with Al-Si/Al-Si-Cr coatings is prepared by slurry process and vacuum diffusion, and the hot corrosion behavior of the stainless steel with/without the coatings is studied under the condition of Na2SO4 film at 950 °C in air. Results show that the corrosion kinetics of stainless steel, the stainless steel with Al-Si coating and the stainless steel with Al-Si-Cr coating follow parabolic laws in several segments. After 24 h corrosion, the sequence of the mass gain for the three alloys is the stainless steel with Al-Si-Cr coating coating coating. The corrosion products of the three alloys are layered. Thereinto, the corrosion products of stainless steel without coating are divided into two layers, where the outside layer contains a composite of Fe2O3 and FeO, and the inner layer is Cr2O3. The corrosion products of the stainless steel with Al-Si coating are also divided into two layers, of which the outside layer mainly consists of Cr2O3, and the inner layer is mainly SiO2. The corrosion film of the stainless steel with Al-Si-Cr coating is thin and dense, which combines well with substrate. Thereinto, the outside layer is mainly Cr2O3, and the inside layer is Al2O3. In the matrix of all of the three alloys, there exist small amount of sulfides. Continuous and protective films of Cr2O3, SiO2 and Al2O3 form on the surface of the stainless steel with Al-Si and Al-Si-Cr coatings, which prevent further oxidation or sulfide corrosion of matrix metals, and this is the main reason for the much smaller mass gain of the two alloys than that of the stainless steel without any coatings in the 24 h hot corrosion process.

  3. 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.

  4. Some aspects of anelastic and microplastic creep of pure Al and two Al-alloys

    Energy Technology Data Exchange (ETDEWEB)

    Sgobba, S. (Lab. de Metallurgie Mecanique, Dept. des Materiaux, Ecole Polytechnique Federale de Lausanne (Switzerland)); Kuenzi, H.U. (Lab. de Metallurgie Mecanique, Dept. des Materiaux, Ecole Polytechnique Federale de Lausanne (Switzerland)); Ilschner, B. (Lab. de Metallurgie Mecanique, Dept. des Materiaux, Ecole Polytechnique Federale de Lausanne (Switzerland))

    1993-11-01

    Anelastic creep of pure Al, commercial Al-Cu and a binary Al-Cu alloy has been measured at room temperature by means of a high resolution laser interferometer. The irreversible component of the deformation was also quantified from measurements of the anelastic creep recovery. The dependence of the deformation-time curves on thermal treatment and cold work is analyzed. The mechanisms responsible for the room temperature anelastic creep are discussed. Materials loaded below their elastic limit can present either a pure anelastic behavior (commercial Al-Cu) or additional viscoelastic creep (pure Al, high purity Al-Cu). For commercial Al-Cu, the presence of an irreversible deformation appears to be mainly related to the state of the surface. A viscoelastic after effect has been measured for this alloy after a Cu-electroplating treatment. As a typical result for room temperature creep, the irreversible deformation depends logarithmically on load time. (orig.).

  5. Some aspects of anelastic and microplastic creep of pure Al and two Al-alloys

    International Nuclear Information System (INIS)

    Sgobba, S.; Kuenzi, H.U.; Ilschner, B.

    1993-01-01

    Anelastic creep of pure Al, commercial Al-Cu and a binary Al-Cu alloy has been measured at room temperature by means of a high resolution laser interferometer. The irreversible component of the deformation was also quantified from measurements of the anelastic creep recovery. The dependence of the deformation-time curves on thermal treatment and cold work is analyzed. The mechanisms responsible for the room temperature anelastic creep are discussed. Materials loaded below their elastic limit can present either a pure anelastic behavior (commercial Al-Cu) or additional viscoelastic creep (pure Al, high purity Al-Cu). For commercial Al-Cu, the presence of an irreversible deformation appears to be mainly related to the state of the surface. A viscoelastic after effect has been measured for this alloy after a Cu-electroplating treatment. As a typical result for room temperature creep, the irreversible deformation depends logarithmically on load time. (orig.)

  6. A study of ion damage in Al, Al/Cu and Al/Ag

    International Nuclear Information System (INIS)

    Marikar, P.

    1979-06-01

    Specimens of pure aluminium, aluminium-copper and aluminium-silver have been irradiated with 20 keV helium ions and/or 100 keV aluminium ions and the nature of the damage assessed using transmission electron microscopy. Irradiation with 20 keV helium ions to a dose of 2.7 x 10 15 ions cm -2 results in the formation of interstitial loops and helium gas bubbles. The helium bubbles were detectable only after annealing at a high temperature following irradiation. When the helium preinjected aluminium specimens were irradiated with 100 keV Al + ions to a dose of 84 dpa at temperatures above 150 0 C, voids were observed to form. At a lower dose of 64 dpa, only a high density of dislocation loops was observed. Al-1 wt% Cu alloy containing partially coherent theta' precipitates resists void formation to a considerable extent, and Al-10 wt% Ag alloy containing coherent G.P. zones offers complete resistance to both dislocation loop nucleation and void formation. The experimental results are discussed in the light of the current theories of irradiation induced damage in metals. The importance of the dislocation-sink efficiency for point defects, the gaseous impurity and the alloying elements in determining void formation is highlighted. (author)

  7. Interdiffusion between U(Mo,Pt) or U(Mo,Zr) and Al or Al A356 alloy

    International Nuclear Information System (INIS)

    Komar Varela, C.; Mirandou, M.; Arico, S.; Balart, S.; Gribaudo, L.

    2009-01-01

    Solid state reactions in chemical diffusion couples U-7 wt.%Mo-0.9 wt.%Pt/Al at 580 deg. C and U-7 wt.%Mo-0.9 wt.%Pt/Al A356 alloy, U-7 wt.%Mo-1 wt.%Zr/Al and U-7 wt.%Mo-1 wt.%Zr/Al A356 alloy at 550 deg. C were characterized. Results were obtained from optical and scanning electron microscopy, electron probe microanalysis and X-ray diffraction. The UAl 3, UAl 4 and Al 20 Mo 2 U phases were identified in the interaction layers of γU(Mo,Pt)/Al and γU(Mo,Zr)/Al diffusion couples. Al 43 Mo 4 U 6 ternary compound was also identified in γU(Mo,Zr)/Al due to the decomposition of γU(Mo,Zr) phase. The U(Al,Si) 3 and U 3 Si 5 phases were identified in the interaction layers of γU(Mo,Pt)/Al A356 and γU(Mo,Zr)/Al A356 diffusion couples. These phases are formed due to the migration of Si to the interaction layer. In the diffusion couple U(Mo,Zr)/Al A356, Zr 5 Al 3 phase was also identified in the interaction layer. The use of synchrotron radiation at Brazilian Synchrotron Light Laboratory (LNLS, CNPq, Campinas, Brazil) was necessary to achieve a complete crystallographic characterization.

  8. CuAlO2 and CuAl2O4 thin films obtained by stacking Cu and Al films using physical vapor deposition

    Science.gov (United States)

    Castillo-Hernández, G.; Mayén-Hernández, S.; Castaño-Tostado, E.; DeMoure-Flores, F.; Campos-González, E.; Martínez-Alonso, C.; Santos-Cruz, J.

    2018-06-01

    CuAlO2 and CuAl2O4 thin films were synthesized by the deposition of the precursor metals using the physical vapor deposition technique and subsequent annealing. Annealing was carried out for 4-6 h in open and nitrogen atmospheres respectively at temperatures of 900-1000 °C with control of heating and cooling ramps. The band gap measurements ranged from 3.3 to 4.5 eV. Electrical properties were measured using the van der Pauw technique. The preferred orientations of CuAlO2 and CuAl2O4 were found to be along the (1 1 2) and (3 1 1) planes, respectively. The phase percentages were quantified using a Rietveld refinement simulation and the energy dispersive X-ray spectroscopy indicated that the composition is very close to the stoichiometry of CuAlO2 samples and with excess of aluminum and deficiency of copper for CuAl2O4 respectively. High resolution transmission electron microscopy identified the principal planes in CuAlO2 and in CuAl2O4. Higher purities were achieved in nitrogen atmosphere with the control of the cooling ramps.

  9. Three-Dimensional FIB/EBSD Characterization of Irradiated HfAl3-Al Composite

    Energy Technology Data Exchange (ETDEWEB)

    Hua, Zilong; Guillen, Donna Post; Harris, William; Ban, Heng

    2016-09-01

    A thermal neutron absorbing material, comprised of 28.4 vol% HfAl3 in an Al matrix, was developed to serve as a conductively cooled thermal neutron filter to enable fast flux materials and fuels testing in a pressurized water reactor. In order to observe the microstructural change of the HfAl3-Al composite due to neutron irradiation, an EBSD-FIB characterization approach is developed and presented in this paper. Using the focused ion beam (FIB), the sample was fabricated to 25µm × 25µm × 20 µm and mounted on the grid. A series of operations were carried out repetitively on the sample top surface to prepare it for scanning electron microscopy (SEM). First, a ~100-nm layer was removed by high voltage FIB milling. Then, several cleaning passes were performed on the newly exposed surface using low voltage FIB milling to improve the SEM image quality. Last, the surface was scanned by Electron Backscattering Diffraction (EBSD) to obtain the two-dimensional image. After 50 to 100 two-dimensional images were collected, the images were stacked to reconstruct a three-dimensional model using DREAM.3D software. Two such reconstructed three-dimensional models were obtained from samples of the original and post-irradiation HfAl3-Al composite respectively, from which the most significant microstructural change caused by neutron irradiation apparently is the size reduction of both HfAl3 and Al grains. The possible reason is the thermal expansion and related thermal strain from the thermal neutron absorption. This technique can be applied to three-dimensional microstructure characterization of irradiated materials.

  10. Synthesis and evaluation of polystyrene membranes for use in fuel cells; Sintesis y evaluacion de membranas base poliestireno para uso en celdas a combustible

    Energy Technology Data Exchange (ETDEWEB)

    Benavides, R. [Centro de Investigacion en Quimica Aplicada (CIQA), Saltillo, Coahuila (Mexico)] e-mail: robertob@ciqa.mx; Paula, M.M.S.; Da Silva, L.; Fiori, M.; Coronetti, J.C.; Silvano, W.F. [Lasicom, Universidade do Extremos Sul Catarinense (UNESC), Criciuma, S.C. (Brasil); B.M. Huerta [Centro de Investigacion en Quimica Aplicada (CIQA), Saltillo, Coahuila (Mexico)

    2009-09-15

    Polymeric membranes were prepared using mass copolymerization of acrylic/styrene with weight proportions of 90/10, 92/8 and 94/6 %, while using the cross-linked divinylbenzene (DVB) monomer with weight proportions of 0.1 and 0.001 % to improve the mechanical properties. The copolymers obtained were sulfonates with sulfuric acid concentrated for 0, 30, 85 and 120 minutes to improve its ionic exchange capacity. The materials were characterized using infrared spectroscopy, thermal analysis (TGA and DSC), cross-linked level with% Gel and acidity using titration with sodium hydroxide. The IR spectrum of the membranes before sulfonating shows the existence of traditional polymer bands used with two signals from homopolymers that are lost and two new signals appearing, corroborating the copolymerization reactions. The thermogravimetry shows a higher decomposition temperature for the cross-linked DVB membranes, while the DSC is not very useful for observing transitions due to the hygroscopicity of the membranes. Finally, the percentage of gel is related to the amount of DVB used and the acidity of the membranes increases with increasing amounts of acrylic acid, sulfonation time and DVB percentage, although this value depends a good deal on the ease of solubilizing the material. The ionic properties of the membranes with better mechanical properties were evaluated with a fuel cell prototype. [Spanish] Se prepararon membranas polimericas mediante la copolimerizacion en masa del estireno/acido acrilico en proporciones de 90/10, 92/8 y 94/6 % en peso, al mismo tiempo que se utilizo el monomero entrecruzante divinilbenceno (DVB) en proporciones de 0.1 y 0.001 % en peso, para mejorar sus propiedades mecanicas. Los copolimeros obtenidos fueron sulfonados con acido sulfurico concentrado durante periodos de tiempo de 0, 30, 85 y 120 minutos para mejorar su capacidad de intercambio ionico. Se caracterizaron los materiales mediante espectroscopia infraroja, analisis termicos (TGA y

  11. The Genyornis Egg: Response to Miller et al.'s commentary on Grellet-Tinner et al., 2016

    Science.gov (United States)

    Grellet-Tinner, Gerald; Spooner, Nigel A.; Handley, Warren D.; Worthy, Trevor H.

    2017-04-01

    Williams (1981) and Williams and Rich (1991) attributed Australian Quaternary fossil eggshell that differed from that of emu Dromaius novaehollandiae to the extinct bird Genyornis newtoni without any osteological or embryonic support. Such association by proximity or abundance mirrors the case of the mistaken association of oviraptor eggs to Protoceratops in the 1920's by Andrews (Grellet-Tinner and Makovicky, 2006). No other candidate species was considered, and this attribution has been unchallenged and followed by everyone thereafter. Much research has been done on this Australian eggshell, with one result being that the extinction of the parent of this eggshell is the most well documented for a taxon in Australia (e.g., Miller et al., 1999, 2005). Grellet-Tinner et al. (2016) raised several problems with the identity of the eggshell Williams (1981) attributed to Genyornis newtoni and suggested that extinct megapodes of the genus Progura were the more likely layer of this eggshell type, therein referred to as ;putative Genyornis oological material; (PGOM). Miller et al. (2017) challenged our hypothesis stating that ;Based on the dimensions of the reconstructed Spooner Egg,Grellet-Tinner et al. (2016)argue that PGOM is too small for a bird with the body mass estimated for Genyornis (168-275 kg) … …[and] …. None of the additional PGOM observations reported byGrellet-Tinner et al. (2016)are inconsistent with a Genyornis parent;. Here we take the opportunity to respond to their critique, the basis of which resolves into a few points, which we address in turn.

  12. Characterization of Al/Ni multilayers and their application in diffusion bonding of TiAl to TiC cermet

    Energy Technology Data Exchange (ETDEWEB)

    Cao, J., E-mail: cao_jian@hit.edu.cn [State Key Lab of Advanced Welding Production Technology, Harbin Institute of Technology, Harbin, 150001 (China); Center for Composite Materials and Structures, Harbin Institute of Technology, Harbin, 150001 (China); Song, X.G. [State Key Lab of Advanced Welding Production Technology, Harbin Institute of Technology, Harbin, 150001 (China); Wu, L.Z. [Center for Composite Materials and Structures, Harbin Institute of Technology, Harbin, 150001 (China); Qi, J.L.; Feng, J.C. [State Key Lab of Advanced Welding Production Technology, Harbin Institute of Technology, Harbin, 150001 (China)

    2012-02-29

    The Al/Ni multilayers were characterized and diffusion bonding of TiAl intermetallics to TiC cermets was carried out using the multilayers. The microstructure of Al/Ni multilayers and TiAl/TiC cermet joint was investigated. The layered structures consisting of a Ni{sub 3}(AlTi) layer, a Ni{sub 2}AlTi layer, a (Ni,Al,Ti) layer and a Ni diffusion layer were observed from the interlayer to the TiAl substrate. Only one AlNi{sub 3} layer formed at the multilayer/TiC cermet interface. The reaction behaviour of Al/Ni multilayers was characterized by means of differential scanning calorimeter (DSC) and X-ray diffraction. The initial exothermic peak of the DSC curve was formed due to the formation of Al{sub 3}Ni and Al{sub 3}Ni{sub 2} phases. The reaction sequence of the Al/Ni multilayers was Al{sub 3}Ni {yields} Al{sub 3}Ni{sub 2} {yields} AlNi {yields} AlNi{sub 3} and the final products were AlNi and AlNi{sub 3} phases. The shear strength of the joint was tested and the experimental results suggested that the application of Al/Ni multilayers improved the joining quality. - Highlights: Black-Right-Pointing-Pointer Diffusion bonding of TiAl to TiC cermet was realized using Al/Ni multilayer. Black-Right-Pointing-Pointer The reaction sequence of the Al/Ni multilayers was Al{sub 3}Ni {yields} Al{sub 3}Ni{sub 2} {yields} AlNi {yields} AlNi{sub 3}. Black-Right-Pointing-Pointer The interfacial microstructure of the joint was clarified. Black-Right-Pointing-Pointer The application of Al/Ni multilayers improved the joining quality.

  13. Efecto sobre la viabilidad celular de una nueva serie de espirosteroides sintéticos en células PC12 Effect of a new series of synthetic spiroteroids on the PC12 cell line viability

    Directory of Open Access Journals (Sweden)

    Laura García-Pupo

    2013-03-01

    Full Text Available Introducción: la diosgenina y sus derivados se han descrito como potentes inhibidores de la proliferación en varias líneas tumorales. Sin embargo otras moléculas relacionadas estructuralmente con dichos derivados, se han reportado como candidatos terapéuticos y otras de ellas se incluyen en alimentos de consumo humano. Objetivo: el presente trabajo evalúa el efecto sobre la viabilidad celular de una nueva serie de espiroesteroides sintéticos derivados de la diosgenina, en células tipo neurales PC12. Métodos: la viabilidad de los cultivos de PC12 se determinó mediante el ensayo de MTT y se calcularon descriptores moleculares teóricos como la lipofilicidad (logP virtual y la superficie de área polar (SAP, con el objetivo de establecer relaciones estructura-actividad. Resultados: nuestros resultados demuestran que solo el acido taurodesoxicólico disminuye de manera significativa la viabilidad celular. Más aun, dicha molécula presenta valores menores y mayores de logP virtual y SAP, respectivamente, respecto al resto de los esteroides de la serie. Conclusiones: los resultados anteriores avalan el estudio del acido taurodesoxicólico como potencial inhibidor de la proliferación celular y al resto de las moléculas de la serie como candidatos neuroprotectores a evaluar en esta misma línea celular y dosis de tratamiento.Introduction: diosgenin and its derivatives have been described as potent anti-proliferative compounds in several tumor cell lines. However, other structurally-related compounds are reported to exert neuroprotective activity and are also included in food for human consumption. Objective: to evaluate the effect of a novel series of diogesin-derived synthetic spirosteroids on cellular viability of neuron-like PC12 cell line. Methods: cellular viability was determined by the MTT assay along with some theorical molecular descriptors, such as lipophilicity and polar surface area, in order to establish the structure

  14. UNDERSTANDING THE MULTIDIMENSIONAL ISLAMIC FAITH THROUGH ‘ABD AL-GHANI AL-NABULUSI’S MYSTICAL PHILOSOPHY

    Directory of Open Access Journals (Sweden)

    Naoki Yamamoto

    2013-12-01

    Full Text Available This paper tries to present a new perspective on Islamic faith and Muslim identity to Muslim minorities who are challenged in practicing or following Islamic law in non-Islamic countries or non-Muslims in the contemporary world. It will uncover the multidimensional perspective of the concept of faith based on sin (dhanb and repentance (tawbah through the mystical philosophy of a Syrian scholar, Abd al-Ghani al-Nabulusi (d. 1143/1741 of the 18th century Ottoman Damascus who contributed to the field of Sufism particularly based on Ibn ‘Arabi’s thought of wahdat al-wujud (oneness of being and insan kamil (the perfect man. Nabulusi believes that anyone who lived during the inexistence of prophet’s revelation, inhabited an isolated place cut off from information about Islam, or lived in dar al-harb and did not make a hijra to dar al-islam could not be regarded as sinful in their deeds. However, faith in Allah is essential and infidelity is not forgiven regardless whether or not they live in dar al-islam or dar al-harb. Further, Nabulusi insists that true faith can be achieved by understanding the sin of existence; the ignorance of the difference of existence between Allah and men.  [Artikel ini menjelaskan identitas keberagamaan umat Islam minoritas yang dituntut untuk menerapkan syariat, namun harus hidup di negara non-muslim, dengan mendiskusikan perspektif multidimensional terhadap konsep dosa dan tobat seperti dikembangkan oleh Abd al-Ghanī al-Nabulusī (1143/1741, seorang sufi pemikir Syria, khususnya  wahdat al-wujūd dan insan kamil, yang hidup di masa kesultanan Usmani di Damaskus. Nabulusī berkeyakinan bahwa siapa saja yang hidup sebelum turunnya wahyu di masa Nabi, hidup di daerah terpencil yang tidak mengenal Islam, atau hidup di dar al-harb dan tidak hijrah ke dar al-islam, tidaklah dibebani dosa atas perbuatannya. Namun demikian, iman kepada Allah amatlah penting dan kekufuran tidaklah dimaafkan, baik seseorang tersebut hidup

  15. 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.``

  16. Rupture of Al matrix in U-Mo/Al dispersion fuel by fission induced creep

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Gwan Yoon; Sohn, Dong Seong [UNIST, Daejeon (Korea, Republic of); Kim, Yeon Soo [Argonne National Laboratory, Argonnge (United States); Lee, Kyu Hong [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    This phenomenon was found specifically in the dispersion fuel plate with Si addition in the Al matrix to suppress interaction layer (IL) formation between UMo and Al. It is known that the stresses induced by fission induced swelling in U-Mo fuel particles are relieved by creep deformation of the IL, surrounding the fuel particles, that has a much higher creep rate than the Al matrix. Thus, when IL growth is suppressed, the stress is instead exerted on the Al matrix. The observed rupture in the Al matrix is believed to be caused when the stress exceeded the rupture strength of the Al matrix. In this study, the possibility of creep rupture of the Al matrix between the neighboring U-Mo fuel particles was examined using the ABAQUS finite element analysis (FEA) tool. The predicted rupture time for a plate was much shorter than its irradiation life indicating a rupture during the irradiation. The higher stress leads Al matrix to early creep rupture in this plate for which the Al matrix with lower creep strain rate does not effectively relieve the stress caused by the swelling of the U-Mo fuel particles. For the other plate, no rupture was predicted for the given irradiation condition. The effect of creeping of the continuous phase on the state of stress is significant.

  17. Effect of Al and AlP on the microstructure of Mn-30 wt.%Si alloy

    Energy Technology Data Exchange (ETDEWEB)

    Wu Yuying [Key Laboratory of Liquid Structure and Heredity of Materials, Ministry of Education, Shandong University, Jing Shi Road 73, Jinan 250061 (China); Liu Xiangfa [Key Laboratory of Liquid Structure and Heredity of Materials, Ministry of Education, Shandong University, Jing Shi Road 73, Jinan 250061 (China)], E-mail: xfliu@sdu.edu.cn

    2008-04-15

    Effect of Al and AlP particles on the microstructure of near eutectic Mn-Si alloy (Mn-30 wt.%Si) was studied by Electron Probe Micro-analyzer (EPMA) and Differential Scanning Calorimeter (DSC). Crystal lattice correspondence analyses show that both Al and AlP have good lattice matching coherence relationships with MnSi phase, and the addition of Al and AlP particles results in an abnormal eutectic structure, i.e. the eutectic constitution MnSi and Mn{sub 5}Si{sub 3} precipitate separately: MnSi precipitates firstly, and then the Mn{sub 5}Si{sub 3} phase.

  18. Elastocaloric effect in CuAlZn and CuAlMn shape memory alloys under compression

    OpenAIRE

    Qian, Suxin; Geng, Yunlong; Wang, Yi; Pillsbury, Thomas E.; Hada, Yoshiharu; Yamaguchi, Yuki; Fujimoto, Kenjiro; Hwang, Yunho; Radermacher, Reinhard; Cui, Jun; Yuki, Yoji; Toyotake, Koutaro; Takeuchi, Ichiro

    2016-01-01

    This paper reports the elastocaloric effect of two Cu-based shape memory alloys: Cu68Al16Zn16 (CuAlZn) and Cu73Al15Mn12 (CuAlMn), under compression at ambient temperature. The compression tests were conducted at two different rates to approach isothermal and adiabatic conditions. Upon unloading at a strain rate of 0.1 s−1 (adiabatic condition) from 4% strain, the highest adiabatic temperature changes (ΔTad) of 4.0 K for CuAlZn and 3.9 K for CuAlMn were obtained. The maximum stress and hystere...

  19. Formation of Al3Ti/Mg composite by powder metallurgy of Mg-Al-Ti system.

    Science.gov (United States)

    Yang, Zi R; Qi Wang, Shu; Cui, Xiang H; Zhao, Yu T; Gao, Ming J; Wei, Min X

    2008-07-01

    An in situ titanium trialuminide (Al 3 Ti)-particle-reinforced magnesium matrix composite has been successfully fabricated by the powder metallurgy of a Mg-Al-Ti system. The reaction processes and formation mechanism for synthesizing the composite were studied by differential scanning calorimetry (DSC), x-ray diffractometry (XRD), scanning electron microscopy (SEM) and energy-dispersive x-ray spectroscopy (EDS). Al 3 Ti particles are found to be synthesized in situ in the Mg alloy matrix. During the reaction sintering of the Mg-Al-Ti system, Al 3 Ti particles are formed through the reaction of liquid Al with as-dissolved Ti around the Ti particles. The formed intermetallic particles accumulate at the original sites of the Ti particles. As sintering time increases, the accumulated intermetallic particles disperse and reach a relatively homogeneous distribution in the matrix. It is found that the reaction process of the Mg-Al-Ti system is almost the same as that of the Al-Ti system. Mg also acts as a catalytic agent and a diluent in the reactions and shifts the reactions of Al and Ti to lower temperatures. An additional amount of Al is required for eliminating residual Ti and solid-solution strengthening of the Mg matrix.

  20. Al-‘Alāqah baina Ushūl al-Fiqh wa Maqāshidi al-Sharīah wa al-Da’wah ilā Ta’sīsi ‘Ilmi al-Maqāshid

    Directory of Open Access Journals (Sweden)

    Anggraini Binti Ramli

    2016-12-01

    Full Text Available The study of Maqāshid sharīa is an important point in the discussion of Islamic legal theory (ushūl al-fiqh. Serious debates began to emerge in the 19th century among Islamic jurists concerning the position of maqāshid sharīa. At least, there are three important debates in the history; first, whether maqāshid is part of the discussion ushūl al-fiqh; second, is maqāshid sharīa built upon a foundation of classical Islamic jurisprudence (fiqh; and third, whether the maqāshid sharīa study is able to become an independent science that is separated from the study of classical Islamic jurisprudence. This article tries to present a discussion of the three paradigms by employing a descriptive-analytic method. The results of this study uncover that the study of maqāshid sharīa is like two sides of one coin; theoretically it is a distinctive study from ushūl al-fiqh, but it cannot be separated from one another. Ushūl al-fiqh has become the foundation to find out more details about the study of maqashid sharia. The separation between classical Islamic jurisprudence (fiqh and maqāshid sharīa study conducted by Islamic jurists is a relative separation.

  1. Solutional Landforms of Gabal Al-Qaraha, the Oasis of Al-Hasa, Saudi Arabia

    OpenAIRE

    Embabi, Nabil S.

    1981-01-01

    Jabal Al-Qarah is one of the small outlier hills at the Oasis of Al-Hasa, lying at about lOkm ENE of Al-Hafuf Town. The solutional forms of Al-Qarah hill discussed in this paper are as follows : 1. A calcareous duricrust which covers the top and some of the slopes of the hill. 2. Rock Pillars which are long columns of white lime-stone. 3. Huge crevasses which are wide erosional openings along vertical joints. 4. Narrow, sinuous caves inside the hill. 5. Pedestal rocks with mushroo...

  2. Comparison on the interaction of Al3+/nano-Al13 with calf thymus DNA /salmon sperm DNA

    Science.gov (United States)

    Ma, Fei; Ma, Yue; Du, Changwen; Yang, Xiaodi; Shen, Renfang

    2015-11-01

    The conformation change, binding mode and binding site between Al3+/nano-Al13 and calf thymus DNA/salmon sperm DNA were investigated by UV-vis absorption, FTIR spectra, Raman spectroscopy and CD spectra, as well as melting curves measurement. The UV-vis spectra and circular dichroism spectra results suggested that the phosphate group structure was changed when Al3+ interacted with DNA, while the double-helix was distorted when nano-Al13 interacted with DNA. The FTIR and Raman spectroscopy revealed that the binding sites were Al3+ … PO2, Al3+ … N7/guanine PO2 … Al13 … N7-C8/guanine with calf thymus DNA, and Al3+ … N3-O2/cytosine, Al3+ … N7-C8/guanine, PO2 … Al13 … N7-C8/guanine, PO2 … Al13 … N1/adenine with salmon sperm DNA, respectively. The electrostatic binding was existed between Al3+ and DNA, and the electrostatic binding and complexing were found between nano-Al13 and DNA.

  3. Bukti Kebenaran Al-quran

    OpenAIRE

    Aliyah, Sri

    2015-01-01

    Al Quran is the greatest miracles of Muhammad SAW as the direction of humankind in order to reach eternal happiness. Scientific evidences show that Al Quran has the truth massages, although it was released far before the finding of modern sciences. The researches continue to study the truth of Al Quran an it revealed the historical fact.

  4. Sintering of (Ni,Mg)(Al,Fe)2O4 Materials and their Corrosion Process in Na3AlF6-AlF3-K3AlF6 Electrolyte

    Science.gov (United States)

    Xu, Yibiao; Li, Yawei; Yang, Jianhong; Sang, Shaobai; Wang, Qinghu

    2017-06-01

    The application of ledge-free sidewalls in the Hall-Héroult cells can potentially reduce the energy requirement of aluminum production by about 30 pct (Nightingale et al. in J Eur Ceram, 33:2761-2765, 2013). However, this approach poses great material challenges since such sidewalls are in direct contact with corrosive electrolyte. In the present paper, (Ni,Mg)(Al,Fe)2O4 materials were prepared using fused magnesia, reactive alumina, nickel oxide, and iron oxide powders as the starting materials. The sintering behaviors of specimens as well as their corrosion resistance to molten electrolyte have been investigated by means of X-ray diffraction and scanning electron microscope. The results show that after firing at temperature ranging from 1673 K (1400 °C) up to 1873 K (1600 °C), all the specimens prepared are composed of single-phase (Ni,Mg)(Al,Fe)2O4 composite spinel, the lattice parameter of which increases with increasing Fe3+ ion concentration. Increasing the iron oxide content enhances densification of the specimens, which is accompanied by the formation of homogeneously distributed smaller pores in the matrix. The corrosion tests show that corrosion layers consist of fluoride and Ni(Al,Fe)2O4 composite spinel grains are produced in specimens with Fe/Al mole ratio no more than 1, whereas dense Ni(Al,Fe)2O4 composite spinel layers are formed on the surface of the specimens with Fe/Al mole ratio more than 1. The dense Ni(Al,Fe)2O4 composite spinel layers formed improve the corrosion resistance of the specimens by inhibiting the infiltration of electrolyte and hindering the chemical reaction between the specimen and electrolyte.

  5. Synthesis of Al(OH3 Nanostructures from Al(OH3 Microagglomerates via Dissolution-Precipitation Route

    Directory of Open Access Journals (Sweden)

    Bo Yu

    2013-01-01

    Full Text Available A facile method was developed to synthesize Al(OH3 nanostructures from Al(OH3 microagglomerates by dissolution in 9.0 mol·L−1 NaOH at 115°C followed by dilution and aging of the solution at room temperature. The influence of Al(OH3 nanoseed and surfactants as sodium dodecyl sulfate (SDS, polyethylene glycol 6000 (PEG6000, and cetyltrimethylammonium bromide (CTAB on the formation of the Al(OH3 nano-structures was investigated. The experimental results indicated that the Al(OH3 microspheres composed of nanoparticles were prepared in the blank experiment, while dispersive Al(OH3 nano-particles with a diameter of 80–100 nm were produced in the presence of Al(OH3 nano-seed and CTAB.

  6. Effects of Al content on structure and mechanical properties of hot-rolled ZrTiAlV alloys

    International Nuclear Information System (INIS)

    Liang, S.X.; Yin, L.X.; Che, H.W.; Jing, R.; Zhou, Y.K.; Ma, M.Z.; Liu, R.P.

    2013-01-01

    Highlights: • Phase structure is greatly dependent on the Al content. • Intermetallic compound will precipitates while Al content is over 6.9 wt%. • Equiaxed α-phase grains present in the hot-rolled alloy with 6.9 wt% Al. • Alloys with Al content from 3.3 wt% to 5.6 wt% have good mechanical properties. - Abstract: Zirconium alloys show attractive properties for astronautic applications where the most important factors are anti-irradiation, corrosion resistance, anti-oxidant, very good strength-to-weight ratio. The effects of Al content (2.2–6.9 wt%) on structure and mechanical properties of the hot-rolled ZrTiAlV alloy samples were investigated in this study. Each sample of the hot-rolled ZrTiAlV alloys with Al contents from 2.2 wt% to 5.6 wt% is composed of the α phase and β phase, meanwhile, the relative content of the α phase increased with the Al content. However, the (ZrTi) 3 Al intermetallic compound was observed as the Al content increased to 6.9 wt%. Changes of phase compositions and structure with Al content distinctly affected mechanical properties of ZrTiAlV alloys. Yield strength of the alloy with 2.2 wt% Al is below 200 MPa. As Al content increased to 5.6 wt%, the yield strength, tensile strength and elongation of the examined alloy are 1088 MPa, 1256 MPa and 8%, respectively. As Al content further increased to 6.9 wt%, a rapid decrease in ductility was observed as soon as the (ZrTi) 3 Al intermetallic compound precipitated. Results show that the ZrTiAlV alloys with Al contents between 3.3 wt% and 5.6 wt% have excellent mechanical properties

  7. Relationship between Al content and substitution mechanism of Al-bearing anhydrous bridgmanites

    Science.gov (United States)

    Noda, M.; Inoue, T.; Kakizawa, S.

    2017-12-01

    It is considered that two substitution mechanisms, Tschermak substitution and oxygen vacancy substitution, exist in MgSiO3 bridgmanite for the incorporation of Al in anhydrous condition. Kubo and Akaogi (2000) has conducted the phase equilibrium experiment in the system MgSiO3-Al2O3, and established the phase diagram up to 28 GPa. However the careful observation in the bridgmanite shows that the chemical compositions are slightly deviated from Tschermak substitution join. The same tendency can be also observed in the run products by Irifune et al. (1996). This result indicates that pure Tschermak substitution bridgmanite cannot be stable even in the MgSiO3-Al2O3 join experiment. However, the previous studies used powder samples as the starting materials, so the absorbed water may affect the results. Therefore, we tried to conduct the experiment in the join MgSiO3-Al2O3 in extremely anhydrous condition to clarify whether the pure Tschermak substitution bridgmanite can be stable or not. In addition, we also examined the stability of oxygen vacancy bridgmanite in the extremely anhydrous condition for the comparison. The high pressure synthesis experiments were conducted at 28 GPa and 1600-1700° for 1hour using a Kawai-type multi-anvil apparatus. Four different Al content samples were prepared as the starting materials along the ideal substitution line of Tschermak (Al=0.025, 0.05, 0.1, 0.15 mol) and oxygen-vacancy (Al=0.025, 0.05, 0.075, 0.1 mol) substitutions, respectively (when total cation of 2). The glass rods were used as the starting materials to eliminate the absorbed water on the sample surface. The chemical compositions of the synthesized bridgmanite could not be measured by EPMA because of small grain size less than submicron. Therefore the chemical compositions were estimated from the result of the XRD pattern by subtracting the amount of the other phases. The estimated chemical compositions of Tschermak substitution bridgmanites were consistent with the

  8. Análise descritiva quantitativa do palmito de pupunheira Quantitative descriptive analysis of pejibaye palm heart

    Directory of Open Access Journals (Sweden)

    Marta Regina Verruma-Bernardi

    2007-01-01

    Full Text Available Este estudo foi conduzido para descrever o perfil sensorial do palmito de pupunha. A análise descritiva quantitativa (ADQ foi utilizada para descrever os atributos sensoriais relacionados à aparência, aroma, e textura de três marcas comerciais de palmito de pupunha. As amostras foram avaliadas por uma equipe selecionada com onze provadores e foram definidos nove atributos sensoriais: cor amarela, aparência uniforme e úmida, aroma e sabor não característicos, sabor acido, residual acido e textura macia. Houve diferenças significativas em seis atributos entre as três marcas testadas. Os provadores descreveram os palmitos de pupunha como: cor amarela clara, aparência uniforme e úmida, aroma e sabor não característicos e sabor ácido com valores intermediários, residual acido e amargor final com valores de pouco e textura muito macia a uma textura intermediária.This research was carried out to establish the sensory profile of pejibaye palm heart. The quantitative descriptive analysis was used to establish the sensory attributes related to appearance, flavor, taste and texture of tree commercial marks of pejibaye palm heart. These samples were evaluated by eleven trained panelists who described nine sensory attributes: yellow color, uniform and humid appearance, non-characteristic aroma and flavor, acid flavor, residual acid taste, and soft texture. There were significant differences in six attributes among the three tested marks. Panelists described the pejibaye palm heart as: light yellow color, uniform and humid appearance, non-characteristic aroma and flavor, acid flavor with medium values, acid residual taste and bitterness final taste from little values and high soft texture to an medium value texture.

  9. Modeling boron separation from water by activated carbon, impregnated and unimpregnated

    Energy Technology Data Exchange (ETDEWEB)

    Ristic, M.; Grbavcic, Z. [Belgrade Univ., Belgrade (BA). Faculty of Technology and Metallurgy; Marinovic, V. [Belgrade Univ., Belgrade (BA). Ist. of Technical Science of the Serbian Academy of Science and Arts

    2000-10-01

    The sorption of boron from boric acid water solution by impregnated activated carbon has been studied. Barium, calcium, mannitol, tartaric acid and citric acid were used as chemical active materials. All processes were performed in a chromatographic continuous system at 22{sup 0} C. Experimental results show that activated carbon impregnated with mannitol is effective in removing boron from water. The separation of boron from the wastewater from a factory for producing enameled dishes by activated carbon impregnated with mannitol was also performed. Two models have been applied to describe published and new data on boron sorption by impregnated activated carbon. Both of them are based on the analysis of boron concentration response to the step input function. This led to a mathematical model that quite successfully described impregnation effects on adsorption capacities. [Italian] E' stato studiato l'assorbimento del boro, mediante carbone attivo impregnato, da soluzioni acquose di acido borico. Quali materiali chimici attivi sono stati utilizzati: bario, calcio, mannitolo, acido tartarico ed acido citrico. Tutti i processi sono stati condotti in un sistema cromatografico continuo a 22{sup 0}C. I risultati sperimentali mostrano che il carbone attivo impregnato con mannitolo e' efficace nella rimozione del boro dall'acqua. E' anche stata effettuata la separazione del boro da acque di scarico di un'industria per la produzione di piatti smaltati mediante carbone attivo impregnato con mannitolo. Sono stati applicati due modelli per descrivere i risultati, pubblicati e nuovi, dell'assorbimento del boro mediante carbone attivo impregnato. Entrambi sono basati sull'analisi della risposta alla concentrazione di boro successivamente incrementata a stadi. Cio' porta ad un modello matematico che descrive abbastanza soddisfacentemente gli effetti dell'impregnazione sulla capacita' di assorbimento.

  10. Burden of rare variants in ALS genes influences survival in familial and sporadic ALS.

    Science.gov (United States)

    Pang, Shirley Yin-Yu; Hsu, Jacob Shujui; Teo, Kay-Cheong; Li, Yan; Kung, Michelle H W; Cheah, Kathryn S E; Chan, Danny; Cheung, Kenneth M C; Li, Miaoxin; Sham, Pak-Chung; Ho, Shu-Leong

    2017-10-01

    Genetic variants are implicated in the development of amyotrophic lateral sclerosis (ALS), but it is unclear whether the burden of rare variants in ALS genes has an effect on survival. We performed whole genome sequencing on 8 familial ALS (FALS) patients with superoxide dismutase 1 (SOD1) mutation and whole exome sequencing on 46 sporadic ALS (SALS) patients living in Hong Kong and found that 67% had at least 1 rare variant in the exons of 40 ALS genes; 22% had 2 or more. Patients with 2 or more rare variants had lower probability of survival than patients with 0 or 1 variant (p = 0.001). After adjusting for other factors, each additional rare variant increased the risk of respiratory failure or death by 60% (p = 0.0098). The presence of the rare variant was associated with the risk of ALS (Odds ratio 1.91, 95% confidence interval 1.03-3.61, p = 0.03), and ALS patients had higher rare variant burden than controls (MB, p = 0.004). Our findings support an oligogenic basis with the burden of rare variants affecting the development and survival of ALS. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  11. Influence of Al grain boundaries segregations and La-doping on embrittlement of intermetallic NiAl

    Energy Technology Data Exchange (ETDEWEB)

    Kovalev, Anatoly I., E-mail: a_kovalev@sprg.ru; Wainstein, Dmitry L.; Rashkovskiy, Alexander Yu.

    2015-11-01

    Highlights: • We investigated Al grain boundaries segregations in ordered pure and La-doped NiAl. • Structural segregation of Al decreases critical strain for brittle cracks nucleation. • La alloying sharply improves plasticity of NiAl intermetallic. • Metallicity of interatomic bonds on grain boundaries increases at La alloying. • We have experimentally measured by EELFS that La atoms are located in Al sublattice. - Abstract: The microscopic nature of intergranular fracture of NiAl was experimentally investigated by the set of electron spectroscopy techniques. The paper demonstrates that embrittlement of NiAl intermetallic compound is caused by ordering of atomic structure that leads to formation of structural aluminum segregations at grain boundaries (GB). Such segregations contain high number of brittle covalent interatomic bonds. The alloying by La increases the ductility of material avoiding Al GB enrichment and disordering GB atomic structure. The influence of La alloying on NiAl mechanical properties was investigated. GB chemical composition, atomic and electronic structure transformations after La doping were investigated by AES, XPS and EELFS techniques. To qualify the interatomic bonds metallicity the Fermi level (E{sub F}) position and electrons density (n{sub eff}) in conduction band were determined in both undoped and doped NiAl. Basing on experimental results the physical model of GB brittleness formation was proposed.

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

    KAUST Repository

    Wang, Junsheng; Horsfield, Andrew; Lee, Peter D.; Brommer, Peter

    2010-01-01

    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.

  13. 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.

  14. Strength of Al and Al-Mg/alumina bonds prepared using ultrahigh vacuum diffusion bonding

    International Nuclear Information System (INIS)

    King, W.E.; Campbell, G.H.; Wien, W.L.; Stoner, S.L.

    1994-01-01

    The authors have measured the cross-breaking strength of Al and Al-Mg alloys bonded with alumina. Diffusion bonding of Al and Al-Mg alloys requires significantly more bonding time than previously thought to obtain complete bonding. In contrast to previous diffusion bonding studies, fracture morphologies are similar to those obtained in bonds formed by liquid phase reaction; i.e., bonds are as strong or stronger than the ceramic; and fracture tends to propagate in the metal for pure Al and near the interface in the ceramic for the alloys. There are indications that the fracture morphology depends on Mg content and therefore on plasticity in the metal

  15. Wear protection in cutting tool applications by PACVD (Ti,Al)N and Al2O3 coatings

    International Nuclear Information System (INIS)

    Kathrein, M.; Heiss, M.; Rofner, R.; Schleinkofer, U.; Schintlmeister, W.; Schatte, J.; Mitterer, C.

    2001-01-01

    Various (Ti,Al)N-, Al 2 O 3 -, and (Ti,Al)N/Al 2 O 3 multilayer coatings were deposited onto cemented carbide cutting tool inserts by a plasma assisted chemical vapor deposition (PACVD) technique. Al 2 O 3 coatings were deposited using the gaseous mixture AlCl 3 , Ar, H 2 , and O 2 . (Ti,Al)N intermediate layers were deposited in the same device using the process mentioned and the gases AICl 3 , Ar, H 2 , TiCl 4 and N 2 . The unique properties of (Ti,Al)N/Al 2 O 3 multilayer coatings result in superior wear protection for cutting inserts applied in severe multifunction cutting processes. The influence of different deposition temperatures an structure and properties of the coatings like crystallographic phases, chemical composition, mechanical and technological properties is shown. PACVD (Ti,Al)N/Al 2 O 3 coated cutting inserts with fine grained crystalline α/κ-Al 2 O 3 offer performance advantages which are superior with respect to coatings deposited by chemical vapor deposition (CVD) due to the low deposition temperature applied. (author)

  16. Current transport mechanism in graphene/AlGaN/GaN heterostructures with various Al mole fractions

    Science.gov (United States)

    Pandit, Bhishma; Seo, Tae Hoon; Ryu, Beo Deul; Cho, Jaehee

    2016-06-01

    The current transport mechanism of graphene formed on AlxGa1-xN/GaN heterostructures with various Al mole fractions (x = 0.15, 0.20, 0.30, and 0.40) is investigated. The current-voltage measurement from graphene to AlGaN/GaN shows an excellent rectifying property. The extracted Schottky barrier height of the graphene/AlGaN/GaN contacts increases with the Al mole fraction in AlGaN. However, the current transport mechanism deviates from the Schottky-Mott theory owing to the deterioration of AlGaN crystal quality at high Al mole fractions confirmed by reverse leakage current measurement.

  17. Current transport mechanism in graphene/AlGaN/GaN heterostructures with various Al mole fractions

    Directory of Open Access Journals (Sweden)

    Bhishma Pandit

    2016-06-01

    Full Text Available The current transport mechanism of graphene formed on AlxGa1−xN/GaN heterostructures with various Al mole fractions (x = 0.15, 0.20, 0.30, and 0.40 is investigated. The current–voltage measurement from graphene to AlGaN/GaN shows an excellent rectifying property. The extracted Schottky barrier height of the graphene/AlGaN/GaN contacts increases with the Al mole fraction in AlGaN. However, the current transport mechanism deviates from the Schottky-Mott theory owing to the deterioration of AlGaN crystal quality at high Al mole fractions confirmed by reverse leakage current measurement.

  18. Assessment of phase constitution on the Al-rich region of rapidly solidified Al-Co-Fe-Cr alloys

    International Nuclear Information System (INIS)

    Wolf, W.; Bolfarini, C.; Kiminami, C.S.; Botta, W.J.

    2016-01-01

    The formation of quasicrystalline approximants in rapidly solidified Al-Co-Fe-Cr alloys was investigated. Alloys of atomic composition Al 71 Co 13 Fe 8 Cr 8 , Al 77 Co 11 Fe 6 Cr 6 and Al 76 Co 19 Fe 4 Cr 1 were produced using melt spinning and arc melting methods and their microstructural characterization was carried out by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. Up to the present there is no consensus in the literature regarding the formation of quasicrystalline phase or quasicrystalline approximants in the Al 71 Co 13 Fe 8 Cr 8 alloy. This work presents, for the first time, a detailed structural characterization of selected alloys in the Al-Co-Fe-Cr system close to the atomic composition Al 71 Co 13 Fe 8 Cr 8 . The results indicated the samples to be composed, mostly, by two intermetallic phases, which are quaternary extensions of Al 5 Co 2 and Al 13 Co 4 and are quasicrystalline approximants. Although the Al 5 Co 2 phase has already been reported in the Al 71 Co 13 Fe 8 Cr 8 alloy, the presence of the monoclinic Al 13 Co 4 is now identified for the first time in the as cast state. In the binary Al-Co system a quasicrystalline phase is known to form in a rapidly solidified alloy with composition close to the monoclinic and orthorhombic Al 13 Co 4 phases. This binary quasicrystalline phase presents an average valence electron per atom (e/a) between 1.7 and 1.9; thus, in addition to the Al 71 Co 13 Fe 8 Cr 8 alloy, the compositions Al 77 Co 11 Fe 6 Cr 6 and Al 76 Co 19 Fe 4 Cr 1 were chosen to be within the region of formation of the quaternary extension of the Al 13 Co 4 phase and also within the (e/a) of 1.7 to 1.9. However, no quasicrystalline phase is present in any of the studied alloys. The Al-Co-Fe-Cr system, around the compositions studied, is composed of quaternary extensions of Al-Co intermetallic phases, which present solubility of Fe and Cr at Co atomic sites. - Highlights: •The Al rich region of the Al

  19. Comparison of ALS functionality and plant growth in ALS-inhibitor susceptible and resistant Myosoton aquaticum L.

    Science.gov (United States)

    Liu, Weitang; Bai, Shuang; Jia, Sisi; Guo, Wenlei; Zhang, Lele; Li, Wei; Wang, Jinxin

    2017-10-01

    Herbicide target-site resistance mutations may cause pleiotropic effects on plant ecology and physiology. The effect of several known (Pro197Ser, Pro197Leu Pro197Ala, and Pro197Glu) target-site resistance mutations of the ALS gene on both ALS functionality and plant vegetative growth of weed Myosoton aquaticum L. (water chickweed) have been investigated here. The enzyme kinetics of ALS from four purified water chickweed populations that each homozygous for the specific target-site resistance-endowing mutations were characterized and the effect of these mutations on plant growth was assessed via relative growth rate (RGR) analysis. Plants homozygous for Pro197Ser and Pro197Leu exhibited higher extractable ALS activity than susceptible (S) plants, while all ALS mutations with no negative change in ALS kinetics. The Pro197Leu mutation increased ALS sensitivity to isoleucine and valine, and Pro197Glu mutation slightly increased ALS sensitivity to isoleucine. RGR results indicated that none of these ALS resistance mutations impose negative pleiotropic effects on relative growth rate. However, resistant (R) seeds had a lowed germination rate than S seeds. This study provides baseline information on ALS functionality and plant growth characteristics associated with ALS inhibitor resistance-endowing mutations in water chickweed. Copyright © 2017. Published by Elsevier Inc.

  20. AL FIKR AL BALAGHI FI AL MA’ĂNI ‘INDA AS SAKĂKI FI KITABIHI MIFTAHUL ULUM DIRĂSAH BALAGHIYYAH

    Directory of Open Access Journals (Sweden)

    Talqis Nurdianto

    2018-02-01

    Full Text Available Miftāhul ‘Ulūm, written by al-Sakākī, especially the third part, was the beginning of a new phase in the development of Arabic rhetoric. Al-Sakākī divided the rhetoric into three fields of study, which are  (1 Ma’ānī, (2 Bayān, (3 Badī’. However, his style is influenced by philosophers, theologians and their verbal lexicon, which are difficult to take, especially for the ordinary recipient. Al-Sakākī described that his book containing several types of literature, namely, ‘ilm ṣarf in complete version and its conclusion, derivation science, and the grammatical study in the completeness of Ma’ānī and Bayān. The meaning of Makna is the study of completeness and conclusion. Therefore, books and prose, and poem require al-‘Arūḍ and al-Qawāfī include Ṣarf, Grammar, Ma’ānī, Bayān, limitation, reasoning, al’Arūḍ, and al-Qawāfī. He argued that the fields of study were influential in delivering knowledge to the student in order to reach the goal of the author towards his book.This research was an analytical descriptive study of al-Sakākī rhetoric that focused on the normative aspect represented by rhetorical rule and aesthetic aspects. Those aspects were shown by the feeling. Al-Sakākī rhetoric thought is a method based on mental division and has conducted in the construction of many factors, which the most important of them are philosophy and logic. Keywords: thought, rhetoric, meanings, sakkaki, study

  1. Caracterización y estudio de la fermentación espontánea del suero costeño producido en Montería

    Directory of Open Access Journals (Sweden)

    Mónica Simanca S

    2010-04-01

    Full Text Available Objetivo. Caracterizar el proceso fermentativo del suero costeño elaborado en Montería. Materiales y métodos. Se caracterizó fisicoquímica y bromatológicamente el producto elaborado artesanalmente en Montería; se evaluó durante 24 horas la fermentación espontánea del producto elaborado en las microempresas, se determinó pH, acidez total, concentración de lactosa y mesófilos aerobios cada tres horas. Se aislaron y seleccionaron los microorganismos involucrados en la fermentación, teniendo en cuenta las propiedades de interés tecnológico y se identificaron bioquímicamente por API 50CH (BioMérieux. Resultados. El suero costeño de contenido medio en grasa, presentó una humedad de 76%, extracto etéreo (11.65%, proteína (5.09%, lactosa (4.36%, cenizas (2.88%, cloruros (2.34%, pH (3.94 y acidez (1.4% acido láctico. En la fermentación espontánea se observó un comportamiento inversamente relacionado entre el pH y la acidez, alcanzando al final del estudio un valor de 4.69 y 0.67% de ácido láctico respectivamente; se encontró un porcentaje de lactosa de 4.44% y una población de mesófilos aerobios de 2x109 UFC/mL. Se aislaron tres cepas de bacterias acido lácticas (BAL identificadas como Enterococcus faecium y Lactobacillus brevis. Conclusiones. Las características fisicoquímicas y bromatológicas del suero costeño elaborado en la ciudad de Montería, no presentaron diferencias estadísticamente significativas entre los productos. En la fermentación espontanea hubo consumo de lactosa, aumento de la concentración de mesófilos aerobios y se presentó una relación inversa entre pH y acidez. Se aislaron e identificaron BAL con la posibilidad de ser utilizadas como cultivos iniciadores.

  2. Adsorption mechanism of acids and bases in reversed-phase liquid chromatography in weak buffered mobile phases designed for liquid chromatography/mass spectrometry.

    Science.gov (United States)

    Gritti, Fabrice; Guiochon, Georges

    2009-03-06

    The overloaded band profiles of five acido-basic compounds were measured, using weakly buffered mobile phases. Low buffer concentrations were selected to provide a better understanding of the band profiles recorded in LC/MS analyses, which are often carried out at low buffer concentrations. In this work, 10 microL samples of a 50 mM probe solution were injected into C(18)-bonded columns using a series of five buffered mobile phases at (SW)pH between 2 and 12. The retention times and the shapes of the bands were analyzed based on thermodynamic arguments. A new adsorption model that takes into account the simultaneous adsorption of the acidic and the basic species onto the endcapped adsorbent, predicts accurately the complex experimental profiles recorded. The adsorption mechanism of acido-basic compounds onto RPLC phases seems to be consistent with the following microscopic model. No matter whether the acid or the base is the neutral or the basic species, the neutral species adsorbs onto a large number of weak adsorption sites (their saturation capacity is several tens g/L and their equilibrium constant of the order of 0.1 L/g). In contrast, the ionic species adsorbs strongly onto fewer active sites (their saturation capacity is about 1g/L and their equilibrium constant of the order of a few L/g). From a microscopic point of view and in agreement with the adsorption isotherm of the compound measured by frontal analysis (FA) and with the results of Monte-Carlo calculations performed by Schure et al., the first type of adsorption sites are most likely located in between C(18)-bonded chains and the second type of adsorption sites are located deeper in contact with the silica surface. The injected concentration (50 mM) was too low to probe the weakest adsorption sites (saturation capacity of a few hundreds g/L with an equilibrium constant of one hundredth of L/g) that are located at the very interface between the C(18)-bonded layer and the bulk phase.

  3. A study on wear resistance and microcrack of the Ti3Al/TiAl + TiC ceramic layer deposited by laser cladding on Ti-6Al-4V alloy

    International Nuclear Information System (INIS)

    Li Jianing; Chen Chuanzhong; Squartini, Tiziano; He Qingshan

    2010-01-01

    Laser cladding of the Al + TiC alloy powder on Ti-6Al-4V alloy can form the Ti 3 Al/TiAl + TiC ceramic layer. In this study, TiC particle-dispersed Ti 3 Al/TiAl matrix ceramic layer on the Ti-6Al-4V alloy by laser cladding has been researched by means of X-ray diffraction, scanning electron microscope, electron probe micro-analyzer, energy dispersive spectrometer. The main difference from the earlier reports is that Ti 3 Al/TiAl has been chosen as the matrix of the composite coating. The wear resistance of the Al + 30 wt.% TiC and the Al + 40 wt.% TiC cladding layer was approximately 2 times greater than that of the Ti-6Al-4V substrate due to the reinforcement of the Ti 3 Al/TiAl + TiC hard phases. However, when the TiC mass percent was above 40 wt.%, the thermal stress value was greater than the materials yield strength limit in the ceramic layer, the microcrack was present and its wear resistance decreased.

  4. Study of the 27Al(n,2,)26Al reaction via accelerator mass spectrometry

    International Nuclear Information System (INIS)

    Wallner, A.

    2000-06-01

    The excitation function for the 27 Al(n,2n) 26 Al reaction is expected to show a strongly non-linear behavior in the neutron-energy region around 14 MeV, the neutron energy in D-T plasmas; thus the production rate of 26 Al (t 1/2 =7.2*10 5 a) in D-T fusion environments can in principle be used to measure the temperature of such plasmas. Existing measurements, however, are strongly discordant. Therefore, a new accurate measurement of the 27 Al(n,2n) 26 Al cross sections in the near threshold region (E n =13.5-14.8 MeV) was performed with the goal to achieve relative cross sections with the highest accuracy possible. In addition, the measurements were also designed to provide good absolute cross-section values, as absolute cross sections are important for radioactive waste predictions. Samples of Al metal were irradiated with neutrons in the energy range near threshold (E th =13.55 MeV) at the Radiuminstitutes of both Vienna and St. Petersburg, and in Tokai-mura, Japan. In Tuebingen irradiations with neutrons of higher energies (17 and 19 MeV) were performed. The amount of 26 Al produced during the irradiations was measured via accelerator mass spectrometry (AMS) at the Vienna Environmental Research Accelerator (VERA). This work represents the first 26 Al measurements for this new facility. With this system, a background as low as 3*10 -15 for 26 Al/ 27 Al isotope ratios was obtained, corresponding to a (n,2n) cross section of 0.04 mb. Utilizing AMS, cross sections with much higher precision and considerably closer to the threshold than in previous investigations could be measured. The prerequisite for its application as a temperature monitor, namely a very well known shape of the excitation function was met. A quantitative prediction of the sensitivity of this method for monitoring the temperature in a D-T fusion plasma was therefore possible. For thermal plasmas temperature changes in the order of 5 to 15 % should be detectable. An even higher sensitivity was found

  5. Magnetostrictive properties of FeAl/polyester and FeAl/silicone composites

    Energy Technology Data Exchange (ETDEWEB)

    Riesgo, G. [Dpto. de Ciencias y Técnicas de la Navegación, Universidad de Oviedo, Campus universitario de Gijón, 33203 Gijón (Spain); Carrizo, J. [Dpto. de Física de la Universidad de Oviedo, c/ Calvo Sotelo s/n, 33007 Oviedo (Spain); Elbaile, L., E-mail: elbaile@uniovi.es [Dpto. de Física de la Universidad de Oviedo, c/ Calvo Sotelo s/n, 33007 Oviedo (Spain); Crespo, R.D. [Dpto. de Física de la Universidad de Oviedo, c/ Calvo Sotelo s/n, 33007 Oviedo (Spain); Sepúlveda, R. [Dpto. de Ingeniería Mecánica y de los Materiales, Universidad de Sevilla, Isla Cartuja, 41092 Sevilla (Spain); García, J.A. [Dpto. de Física de la Universidad de Oviedo, c/ Calvo Sotelo s/n, 33007 Oviedo (Spain)

    2017-01-15

    Highlights: • Nanocrystalline powders of FeAl have been obtained from the Fe{sub 81}Al{sub 19} ribbon produced by melt spinning. • The method allows the obtainment of a FeAl solid solution from the starting process. • The microstructure and magnetic properties of the powders were investigated. • Composites with a magnetostriction of 45 ppm have been obtained. - Abstract: Ribbons of composition Fe{sub 81}Al{sub 19} obtained by the melt spinning method have been used to yield powder by mechanical milling. Using this method, a rapid nanocrystallization and a FeAl solid solution phase was obtained from the start of the process. The microstructural and magnetic properties as well as the XRD patterns of the powders were studied in function of the milling time. Grain refinement and an increase of the coercive field were the main transformations resulting from increasing the milling time. Two sets of magnetostrictive composites were produced from the 100 h-milled powder. In one of them polyester was used as matrix and in the other one silicone. In the case of the silicone composites cured in a magnetic field of 140 mT in the longitudinal direction a saturation magnetostriction as high as 45 ppm was obtained.

  6. Thermodynamic calculation of Al-Gd and Al-Gd-Mg phase equilibria checked by key experiments

    International Nuclear Information System (INIS)

    Groebner, J.; Kevorkov, D.; Schmid-Fetzer, R.

    2001-01-01

    The binary Al-Gd and the ternary Al-Gd-Mg systems were calculated using the Calphad method. It is demonstrated that previous interpretation of ternary liquidus temperatures below 700 C must be related to other phase equilibria. The actual ternary liquidus temperatures are much higher, up to some 600 C above the previous interpretation in literature. They are widely governed by the high-melting compounds Al 2 Gd and Al 3 Gd with liquidus surfaces stretching far into the ternary system. A small number of key experiments in this work confirmed the calculated liquidus temperature and the phase relations. The available experimental data in literature fit excellently with the calculation in the binary Al-Gd system. In the ternary Al-Gd-Mg system, which is shown in several sections of the phase diagram, a good agreement can be observed too, considering the necessary reinterpretation of the liquidus temperatures suggested by Rokhlin et al. Ternary solubilities were not found experimentally. The ternary compound Al 4 GdMg (τ) forms in a ternary peritectic reaction at 761 C. (orig.)

  7. Forged HITEMAL: Al-based MMCs strengthened with nanometric thick Al{sub 2}O{sub 3} skeleton

    Energy Technology Data Exchange (ETDEWEB)

    Balog, Martin, E-mail: ummsbama@savba.sk [Institute of Materials and Machine Mechanics, Slovak Academy of Sciences, Racianska 75, 83102 Bratislava (Slovakia); Krizik, Peter; Nosko, Martin; Hajovska, Zuzana [Institute of Materials and Machine Mechanics, Slovak Academy of Sciences, Racianska 75, 83102 Bratislava (Slovakia); Victoria Castro Riglos, Maria [Centro Atómico Bariloche, Av. Bustillo 9.500, 8400 Bariloche, Río Negro (Argentina); Rajner, Walter [New Materials Development GmbH, Römerstrasse 28, 83410 Laufen, Leobendorf (Germany); Liu, De-Shin [National Chung Cheng University, 168 University Rd., Min-Hsiung, 62102 Chia-Yi, Taiwan (China); Simancik, Frantisek [Institute of Materials and Machine Mechanics, Slovak Academy of Sciences, Racianska 75, 83102 Bratislava (Slovakia)

    2014-09-08

    Bulk Al–Al{sub 2}O{sub 3} metal matrix composites (MMCs) named HITEMAL (high temperature aluminum) were fabricated in situ by forging compaction of five different types of gas-atomized commercial purity Al powders with a mean particle size in the range of 1–9 µm. As-forged HITEMAL consisted of (sub)micrometric Al grains (matrix) decorated with nanometric thick amorphous Al{sub 2}O{sub 3} (a-Al{sub 2}O{sub 3}) skeleton. Low-angle grain boundaries (LAGBs) free of Al{sub 2}O{sub 3} were located in the Al grain interior. The Al grain size and the portion of LAGBs increased with the increase in the relative powder surface area. As-forged HITEMAL shows excellent thermal stability up to 400 °C for 24 h. Annealing at temperatures ≥450 °C led to crystallization and morphological transformation from a-Al{sub 2}O{sub 3} skeleton to nanometric γ-Al{sub 2}O{sub 3} particles. Owing to the pinning effect of Al{sub 2}O{sub 3} phase, no Al grain growth took place during annealing up to 500 °C. HITEMAL showed attractive mechanical properties especially when tested at 300 °C (yield strength up to 220 MPa, Young's modulus up to 58 GPa). Despite the presence of a nearly continuous a-Al{sub 2}O{sub 3} skeleton along adjacent Al grains, forged HITEMAL materials had reasonable room temperature elongation of 7–26%. HITEMAL's elongation decreased as the Al grain size decreased and with increased testing temperature. The loss in elongation (uniform and total) was attributed to the inhomogeneous flow, which occurred due to high densities of high angle grain boundaries (dislocation sinks) and small content of LAGBs. The strength of HITEMAL stemmed from grain boundary mediated strengthening mechanisms. The results showed a positive deviation from the Hall–Petch plot, which is typical behavior of ultrafine-grained metals. Transformation of a-Al{sub 2}O{sub 3} skeleton to γ-Al{sub 2}O{sub 3} particles led to deterioration of the HITEMAL strength and Young's modulus.

  8. Determination of Al concentration in Al doped ZnO using Auger spectra excited by Mo X-rays

    International Nuclear Information System (INIS)

    Toth, J.; Koever, L.; Cserny, I.; Varga, D.

    2006-01-01

    Complete text of publication follows. A good conductor with excellent transparency is of crucial importance for the window layer of CIGS solar cells. Al doped ZnO is a good candidate for this purpose, its conductivity depends on the concentration and chemical state of the Al dopant atoms. It was demonstrated that the non-conventional XPS using Mo X-rays for excitation is a very sensitive tool for the detection of Al, P, Si [1, 2, 3]. The present paper compares the experimental ratios for Zn/Al photoinduced peak intensity ratios obtained using both Al and Mo X-ray excitations. The Mo excited Zn/Al intensity ratios can be determined with higher selectivity and sensitivity than the Zn/Al intensity ratios excited by Al X-rays. The experiments were performed with a hemispherical deflector electron spectrometer [4]. The chemical state of the Al was identified to be close to that in Al 2 O 3 . The atomic concentrations were determined using a calibration curve based on ZnO/Al samples with known composition of Al. The energy dependent efficiency of the electron spectrometer was determined comparing REELS spectra of Cu specimen to standard spectra measured by K. Goto (Nagoya Institute of Technology, Japan). For evaluation of the Al atomic concentrations from the measured photoelectron intensities the photoionisation cross-sections of Band et al [5] and the IMFP data of S. Tanuma et al [6] and C.J. Powell and A. Jablonski [7] were used. (author)

  9. Experimental evidences for reducing Mg activation energy in high Al-content AlGaN alloy by MgGa δ doping in (AlN)m/(GaN)n superlattice

    Science.gov (United States)

    Wang, Xiao; Wang, Wei; Wang, Jingli; Wu, Hao; Liu, Chang

    2017-03-01

    P-type doping in high Al-content AlGaN alloys is a main challenge for realizing AlGaN-based deep ultraviolet optoelectronics devices. According to the first-principles calculations, Mg activation energy may be reduced so that a high hole concentration can be obtained by introducing nanoscale (AlN)5/(GaN)1 superlattice (SL) in Al0.83Ga0.17N disorder alloy. In this work, experimental evidences were achieved by analyzing Mg doped high Al-content AlGaN alloys and Mg doped AlGaN SLs as well as MgGa δ doped AlGaN SLs. Mg acceptor activation energy was significantly reduced from 0.378 to 0.331 eV by using MgGa δ doping in SLs instead of traditional doping in alloys. This new process was confirmed to be able to realize high p-type doping in high Al-content AlGaN.

  10. Al-Shebab: An Al-Qaeda Affiliate Case Study (2Rev)

    Science.gov (United States)

    2017-10-01

    deputies responsible for finance , administration, and security. Coordination among regional groups is common.10 The deputy leader of al-Shebab, Mukhtar...Maaliya (Ministry of Finance ) controlled taxation. A complex court system also emerged. Multiple training camps were built that focused on hand-to-hand...Nathan Chandler, Counterterrorism and Counterinsurgency in Somalia: Assessing the Campaign Against Al Shabaab, Rand Corporation , 2016, accessed 6/5

  11. Efecto citoprotector del camu-camu Myrciaria dubia en tres líneas celulares de ratón expuestos in vivo a bromato de potasio

    Directory of Open Access Journals (Sweden)

    Alvis Rafael

    2011-05-01

    Full Text Available Se evaluó in vivo la capacidad citoprotectora del fruto de Myrciaria dubia (Kunth McVaugh Camu-camu frente al daño mutagénico producido por bromato de potasio (68,5 mg/k sobre tres líneas celulares de ratón (hígado, riñón y células sanguíneas. Se utilizó ratones (n= 120 divididos en tres grupos los cuales bebieron ad libitum: TI= control negativo (solo agua y el grupo TIII (control positivo; El grupo TII bebió el extracto acuoso (2% p/v del fruto de camu-camu. A los diez días se inyectó una dosis única de KBr03 (68,5 mg/kg peso corporal vía intraperitoneal, a los grupos TII y TIII. El tratamiento con camu-camu continuo 35 días más, luego los ratones fueron eutanizados para determinar la frecuencia del daño al DNA mediante el protocolo del ensayo cometa alcalino. El grupo TII mostró en todas las líneas celulares el efecto citoprotector del camu-camu (p< 0,05. El efecto dañino al DNA por la acción oxidativa del KBrO3 es inhibido por el extracto acuoso del fruto de camu camu, probablemente por la presencia de los agentes antioxidantes como el Acido ascórbico y los flavonoides.

  12. Experimental evidences for reducing Mg activation energy in high Al-content AlGaN alloy by MgGa δ doping in (AlN)m/(GaN)n superlattice

    OpenAIRE

    Xiao Wang; Wei Wang; Jingli Wang; Hao Wu; Chang Liu

    2017-01-01

    P-type doping in high Al-content AlGaN alloys is a main challenge for realizing AlGaN-based deep ultraviolet optoelectronics devices. According to the first-principles calculations, Mg activation energy may be reduced so that a high hole concentration can be obtained by introducing nanoscale (AlN)5/(GaN)1 superlattice (SL) in Al0.83Ga0.17N disorder alloy. In this work, experimental evidences were achieved by analyzing Mg doped high Al-content AlGaN alloys and Mg doped AlGaN SLs as well as MgG...

  13. Tadris Al Mufradat Li Tathbiq Maharah Al Kalam Fi Madrasah Al Muallimin Al Islamiyyah Li Mahad Bait Al Arqam Balong Jember

    Directory of Open Access Journals (Sweden)

    Muhammad Ardy Zaini

    2017-06-01

    Full Text Available There are four  skills in teaching Arabic. Ie listening, speaking, reading, and writing. Among these four, speaking considered one of the most important objectives of learning foreign language. In order to speak properly, one must know the vocabulary and apply it in a sentence. The aims of this research is to describe the teaching of vocabulary to apply the speaking skill in the school of Islamic teachers in the Institute of Bait al Arqom Balong Jember. This study used qualitative approach. The data collection was taken trough observation, personal interview, history and documentation. The teaching of vocabulary to apply the speaking skill at the Islamic Teachers' School at the Institute of Bait Al Arqam Balong Jember has gone well in terms of planning (general objectives and specific objectives, implementation (materials, use of the teaching method and teaching aids, and evaluation (assessment and evaluation. This teaching is to apply the speaking skill in terms of conversation or dialogue and lecture.

  14. NEK1 genetic variability in a Belgian cohort of ALS and ALS-FTD patients.

    Science.gov (United States)

    Nguyen, Hung Phuoc; Van Mossevelde, Sara; Dillen, Lubina; De Bleecker, Jan L; Moisse, Matthieu; Van Damme, Philip; Van Broeckhoven, Christine; van der Zee, Julie

    2018-01-01

    We evaluated the genetic impact of the amyotrophic lateral sclerosis (ALS) risk gene never in mitosis gene a-related kinase 1 (NEK1) in a Belgian cohort of 278 patients with ALS (n = 245) or ALS with frontotemporal dementia (ALS-FTD, n = 33) and 609 control individuals. We identified 2 ALS patients carrying a loss-of-function (LOF) mutation, p.Leu854Tyrfs*2 and p.Tyr871Valfs*17, that was absent in the control group. A third LOF variant p.Ser1036* was present in 2 sibs with familial ALS but also in an unrelated control person. Missense variants were common in both patients (3.6%) and controls (3.0%). The missense variant, p.Arg261His, which was previously associated with ALS risk, was detected with a minor allele frequency of 0.90% in patients compared to 0.33% in controls. Taken together, NEK1 LOF variants accounted for 1.1% of patients, although interpretation of pathogenicity and penetrance is complicated by the observation of occasional LOF variants in unaffected individuals (0.16%). Furthermore, enrichment of additional ALS gene mutations was observed in NEK1 carriers, suggestive of a "second hit" model were NEK1 variants may modify disease presentation of driving mutations. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  15. The effect of ammonia flow in the AlN spacer on the electrical properties of InAlN/AlN/GaN HEMT structures

    International Nuclear Information System (INIS)

    Gamarra, Piero; Lacam, Cedric; Magis, Michelle; Tordjman, Maurice; Di Forte Poisson, Marie-Antoinette

    2012-01-01

    During the past few years it has been reported that a thin AlN spacer of few nanometers needs to be inserted in InAlN/GaN high electron mobility transistors (HEMTs) to obtain high 2DEG carrier mobility. This work presents a systematic study of the effects of varying the ammonia flow in the AlN spacer of InAlN/AlN/GaN HEMTs grown by low pressure metalorganic vapour phase epitaxy (LP-MOVPE). The strain state, the surface roughness and the growth rate of AlN were found to be dependent on the V/III ratio. In addition the ammonia flow in the interlayer has a strong impact on the structural properties of the subsequent InAlN barrier layer and on the electrical properties of the structure. A sheet resistance as low as 327 Ω/□ with a sheet carrier density of 1.5 x 10 13 cm -2 has been obtained at room temperature. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  16. The effect of ammonia flow in the AlN spacer on the electrical properties of InAlN/AlN/GaN HEMT structures

    Energy Technology Data Exchange (ETDEWEB)

    Gamarra, Piero; Lacam, Cedric; Magis, Michelle; Tordjman, Maurice; Di Forte Poisson, Marie-Antoinette [III-V Lab., Marcussis (France)

    2012-01-15

    During the past few years it has been reported that a thin AlN spacer of few nanometers needs to be inserted in InAlN/GaN high electron mobility transistors (HEMTs) to obtain high 2DEG carrier mobility. This work presents a systematic study of the effects of varying the ammonia flow in the AlN spacer of InAlN/AlN/GaN HEMTs grown by low pressure metalorganic vapour phase epitaxy (LP-MOVPE). The strain state, the surface roughness and the growth rate of AlN were found to be dependent on the V/III ratio. In addition the ammonia flow in the interlayer has a strong impact on the structural properties of the subsequent InAlN barrier layer and on the electrical properties of the structure.istance as low as 327 {omega}/{open_square} with a sheet carrier density of 1.5 x 10{sup 13} cm{sup -2} has been obtained at room temperature. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  17. Assessment of phase constitution on the Al-rich region of rapidly solidified Al-Co-Fe-Cr alloys

    Energy Technology Data Exchange (ETDEWEB)

    Wolf, W., E-mail: witorw@gmail.com [Programa de Pós-Graduação em Ciência e Engenharia de Materiais, Universidade Federal de São Carlos, Rod. Washington Luiz, Km 235, 13565-905 São Carlos, SP (Brazil); Bolfarini, C., E-mail: cbolfa@ufscar.br [Departamento de Engenharia de Materiais, Universidade Federal de São Carlos, Rod. Washington Luiz, Km 235, 13565-905 São Carlos, SP (Brazil); Kiminami, C.S., E-mail: kiminami@ufscar.br [Departamento de Engenharia de Materiais, Universidade Federal de São Carlos, Rod. Washington Luiz, Km 235, 13565-905 São Carlos, SP (Brazil); Botta, W.J., E-mail: wjbotta@ufscar.br [Departamento de Engenharia de Materiais, Universidade Federal de São Carlos, Rod. Washington Luiz, Km 235, 13565-905 São Carlos, SP (Brazil)

    2016-12-15

    The formation of quasicrystalline approximants in rapidly solidified Al-Co-Fe-Cr alloys was investigated. Alloys of atomic composition Al{sub 71}Co{sub 13}Fe{sub 8}Cr{sub 8}, Al{sub 77}Co{sub 11}Fe{sub 6}Cr{sub 6} and Al{sub 76}Co{sub 19}Fe{sub 4}Cr{sub 1} were produced using melt spinning and arc melting methods and their microstructural characterization was carried out by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. Up to the present there is no consensus in the literature regarding the formation of quasicrystalline phase or quasicrystalline approximants in the Al{sub 71}Co{sub 13}Fe{sub 8}Cr{sub 8} alloy. This work presents, for the first time, a detailed structural characterization of selected alloys in the Al-Co-Fe-Cr system close to the atomic composition Al{sub 71}Co{sub 13}Fe{sub 8}Cr{sub 8}. The results indicated the samples to be composed, mostly, by two intermetallic phases, which are quaternary extensions of Al{sub 5}Co{sub 2} and Al{sub 13}Co{sub 4} and are quasicrystalline approximants. Although the Al{sub 5}Co{sub 2} phase has already been reported in the Al{sub 71}Co{sub 13}Fe{sub 8}Cr{sub 8} alloy, the presence of the monoclinic Al{sub 13}Co{sub 4} is now identified for the first time in the as cast state. In the binary Al-Co system a quasicrystalline phase is known to form in a rapidly solidified alloy with composition close to the monoclinic and orthorhombic Al{sub 13}Co{sub 4} phases. This binary quasicrystalline phase presents an average valence electron per atom (e/a) between 1.7 and 1.9; thus, in addition to the Al{sub 71}Co{sub 13}Fe{sub 8}Cr{sub 8} alloy, the compositions Al{sub 77}Co{sub 11}Fe{sub 6}Cr{sub 6} and Al{sub 76}Co{sub 19}Fe{sub 4}Cr{sub 1} were chosen to be within the region of formation of the quaternary extension of the Al{sub 13}Co{sub 4} phase and also within the (e/a) of 1.7 to 1.9. However, no quasicrystalline phase is present in any of the studied alloys. The Al-Co-Fe-Cr system

  18. Corrosion analysis of AlMg2 and AlMgSi using electrochemical method

    International Nuclear Information System (INIS)

    Dian A; Maman Kartaman; Rosika K; Yanlinastuti

    2014-01-01

    Corrosion test of cladding materials and structures of research reactor fuel, AlMgSi and AlMg2 have been performed in demineralized water of pH 2 and 6.7 using an electrochemical method. Corrosion phenomenon is affected by several factor such as composition and condition of solution. The purpose of this activity is to investigate the corrosion phenomena through the determination of the parameters of corrosion and polarization curve. The materials used are AlMg2 and AlMgSi alloy in circular dish shape with an area of 1 Cm"2. Preparation of the test sample is performed through several stages polishing, cleaning and drying procedures followed ASTM G3. The electrochemical method is done by measuring the open circuit potential (OCP), polarization resistance and potentiodynamic in demineralized water of pH 2 and pH 6.7 at temperature of 25°C. The results of the OCP is the corrosion potential (Ecorr) of AlMg2 and AlMgSi each of -906.1 mV and -619.8 mV at pH 2 and -868.6 and -756.7 mV at pH 6.7 mV. The results of measurements by polarization resistance technique showed that the corrosion rate of AlMg2 and AlMgSi in safe category (<2 mpy) at pH 6.7 and at pH 2 corrosion rate increased significantly, but still in the lightweight category (<20 mpy). Potentiodynamic curves showed that the passivation at pH 6.7 is very low while the passivation at pH 2 occurs within a relatively short range potential and followed events corroded. (author)

  19. Catalytic effect of Al and AlN interlayer on the growth and properties of containing carbon films

    International Nuclear Information System (INIS)

    Zhou, Bing; Liu, Zhubo; Tang, Bin; Rogachev, A.V.

    2015-01-01

    Highlights: • DLC and CN x bilayers with Al (AlN) interlayer were fabricated by cathode arc technique. • Complete diffusion of Al and C atoms occurs at the interface of Al/DLC (CN x ) bilayer. • Al/CN x bilayer presents a higher content of Csp 3 /Csp 2 bonds. • The hardness of Al/DLC bilayer decreases but increases for the other bilayers. • Morphology of the bilayers was explained by growth mechanism of DLC and surface state of substrate. - Abstract: Diamond-like carbon (DLC) and carbon nitride (CN x ) bilayer films with Al and AlN interlayer were fabricated by pulse cathode arc technique. The structure, composition, morphology and mechanical properties of the films were investigated by Raman, Auger electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), Knoop sclerometer and surface profilometer. The results indicated that the complete diffusion between C and Al atoms occurs in the Al/DLC and Al/CN x bilayer. Al interlayer induces the increase of the size and ordering of Csp 2 clusters in the films but AlN interlayer increases the disordering degree of Csp 2 clusters. XPS results showed that a higher content of Csp 3 /Csp 2 bonds presents in the Al/CN x bilayer, and Al and AlN interlayer decreases the atomic ratio of N/C. AFM with phase contrast mode illustrated the morphologic characteristics of the bilayer films. All the bilayers show a nano-structural surface. The morphology changes of the bilayer were well explained by the surface state of the substrate and the growth mechanism of DLC films. The hardness of Al/DLC bilayer decreases but it increases for the other bilayers compared to the corresponding DLC (CN x ) monolayer. The internal stress of the bilayer is significantly lower than that of the monolayer except for the AlN/CN x bilayer. These studies could make the difference at the time of choosing a suitable functional film for certain application

  20. Characteristics in AlN/AlGaN/GaN Multilayer-Structured High-Electron-Mobility Transistors

    International Nuclear Information System (INIS)

    Gui-Zhou, Hu; Ling, Yang; Li-Yuan, Yang; Si, Quan; Shou-Gao, Jiang; Ji-Gang, Ma; Xiao-Hua, Ma; Yue, Hao

    2010-01-01

    A new multilayer-structured AlN/AlGaN/GaN heterostructure high-electron-mobility transistor (HEMT) is demonstrated. The AlN/AlGaN/GaN HEMT exhibits the maximum drain current density of 800 mA/mm and the maximum extrinsic transconductance of 170 mS/mm. Due to the increase of the distance between the gate and the two-dimensional electron-gas channel, the threshold voltage shifts slightly to the negative. The reduced drain current collapse and higher breakdown voltage are observed on this AlN/AlGaN/GaN HEMT. The current gain cut-off frequency and the maximum frequency of oscillation are 18.5 GHz and 29.0 GHz, respectively. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  1. 60Co gamma radiation effect on AlGaN//AlN/GaN HEMT devices

    International Nuclear Information System (INIS)

    Wang Yanping; Luo Yinhong; Wang Wei; Zhang Keying; Guo Hongxia; Guo Xiaoqiang; Wang Yuanming

    2013-01-01

    The testing techniques and experimental methods of the 60 Co 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)

  2. Cu-segregation at the Q'/α-Al interface in Al-Mg-Si-Cu alloy

    International Nuclear Information System (INIS)

    Matsuda, Kenji; Teguri, Daisuke; Uetani, Yasuhiro; Sato, Tatsuo; Ikeno, Susumu

    2002-01-01

    Cu segregation was detected at the Q ' /α-Al interface in an Al-Mg-Si-Cu alloy by energy-filtered transmission electron microscopy. By contrast, in a Cu-free Al-Mg-Si alloy no segregation was observed at the interface between the matrix and Type-C precipitate

  3. Effect of Al-5Ti-0.62C-0.2Ce Master Alloy on the Microstructure and Tensile Properties of Commercial Pure Al and Hypoeutectic Al-8Si Alloy

    Directory of Open Access Journals (Sweden)

    Wanwu Ding

    2017-06-01

    Full Text Available Al-5Ti-0.62C-0.2Ce master alloy was synthesized by a method of thermal explosion reaction in pure molten aluminum and used to modify commercial pure Al and hypoeutectic Al-8Si alloy. The microstructure and tensile properties of commercial pure Al and hypoeutectic Al-8Si alloy with different additions of Al-5Ti-0.62C-0.2Ce master alloy were investigated. The results show that the Al-5Ti-0.62C-0.2Ce alloy was composed of α-Al, granular TiC, lump-like TiAl3 and block-like Ti2Al20Ce. Al-5Ti-0.62C-0.2Ce master alloy (0.3 wt %, 5 min can significantly refine macro grains of commercial pure Al into tiny equiaxed grains. The Al-5Ti-0.62C-0.2Ce master alloy (0.3 wt %, 30 min still has a good refinement effect. The tensile strength and elongation of commercial pure Al modified by the Al-5Ti-0.62C-0.2Ce master alloy (0.3 wt %, 5 min increased by roughly 19.26% and 61.83%, respectively. Al-5Ti-0.62C-0.2Ce master alloy (1.5 wt %, 10 min can significantly refine both α-Al grains and eutectic Si of hypoeutectic Al-8Si alloy. The dendritic α-Al grains were significantly refined to tiny equiaxed grains. The morphology of the eutectic Si crystals was significantly refined from coarse needle-shape or lath-shape to short rod-like or grain-like eutectic Si. The tensile strength and elongation of hypoeutectic Al-8Si alloy modified by the Al-5Ti-0.62C-0.2Ce master alloy (1.5 wt %, 10 min increased by roughly 20.53% and 50%, respectively. The change in mechanical properties corresponds to evolution of the microstructure.

  4. Tailoring ultrafine grained and dispersion-strengthened Ti2AlC/TiAl ...

    Indian Academy of Sciences (India)

    and Ti-Al pre-alloyed powders at low temperature of 1150◦C. The composite mainly consisted ... Metal–matrix composites; mechanical properties; microstructures; sintering. 1. Introduction γ-TiAl-based intermetallic alloys have been extensively.

  5. Stagnation of the exploitation of Al ores and the depression of world prices of Al

    Directory of Open Access Journals (Sweden)

    Slavkovský Jozef

    1999-03-01

    Full Text Available In the contribution, data on Al – a metal of the 20th century are compiled together with the problems of genesis of the Al mineral raw ma-terials as well as types of bauxite and Al-laterite deposits. Furthermore, an overview of the world exploitation of bauxite during 1935-1980 is given along with the prognoses to 2000 and present situation (1992-1996. Overviews of the production of Al follows, providing its rela-tion to the bauxite exploitation. Contrary to the prognoses, a stabilization or stagnation has been observed in the exploitation of bauxite and production of Al during nineties, which a tendency is directly reflected in the world price of this commodity. When analyzing the Al prices for a longer period, some serious deviations can be noticed, that however presently represent a long-term minimum. We hope the stagnation of the production and the price decline are only temporary and new possibilities of the utilization of Al will be found soon.

  6. A study on preparation and hydriding of β-Mg2Al3 and γ-Mg17Al12

    International Nuclear Information System (INIS)

    Hadi Suwarno

    2009-01-01

    The mechanism of the synthetic formation of β-Mg 2 Al 3 and γ-Mg 17 Al 12 has been studied. Mechanical alloying of Mg and Al powders with the atomic ratio of Mg:Al = 2:3 in toluene solution yields β-Mg 2 Al 3 compound after milling for 30 h. The γ-Mg 17 Al 12 can be formed by heating the β-Mg 2 Al 3 at 430°C under high vacuum. The measured hydrogen capacities of β-Mg 2 Al 3 and γ-Mg 17 Al 12 as hydride at 300°C are 3.2 and 4.9 wt%, respectively. Microstructure of the Mg-Al specimen shows that on hydriding at 300°C the polygonal shape of the γ-Mg 17 Al 12 changes into irregular shapes which are composed of γ-MgH 2 and Al. (author)

  7. Marinbiologisk optegnelse i NUḪBAT AL-DAHR FĪ ʿAǦ ʾIB AL-BARR WA-AL-BAḤR

    OpenAIRE

    Provencal, Philippe

    2014-01-01

    I det arabiske geografiske værk NUḪBAT AL-DAHR FĪ ʿAǦ ʾIB AL-BARR WA-AL-BAḤR (færdigskrevet mellem 1324 og 1327) fra omtales seks dyr fra Adenbugten. Det dreje sig om savrokke, kuglefisk, pilrokke, pindsvinefisk og hvalhaj. Det sidste dyr har ikke kunnet bestemmes. Artiklen bringer en oversættelse af optegnelsen til engelsk samt både en filologisk som en biologisk kommentar. The aim of this article is to present a medieval Arabic report regarding sixanimals from the Gulf of Aden, to provid...

  8. 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

  9. Adhesive and tribocorrosive behavior of TiAlPtN/TiAlN/TiAl multilayers sputtered coatings over CoCrMo

    Science.gov (United States)

    Canto, C. E.; Andrade, E.; Rocha, M. F.; Alemón, B.; Flores, M.

    2017-09-01

    The tribocorrosion resistance and adherence of multilayer coatings of TiAlPtN/TiAlN/TiAl synthesized by PVD reactive magnetron sputtering over a CoCrMo alloy substrate in 10 periods of 30 min each were analyzed and compared to those of the substrate alone and to that of a TiAlPtN single layer coating of the same thickness. The objective of the present work was to create multilayers with different amounts of Pt in order to enhance the tribocorrosion resistance of a biomedical alloy of CoCrMo. Tribocorrosion tests were performed using Simulated Body Fluid (SBF) at typical body temperature with a tribometer in a pin on disk test. The elemental composition and thickness of the coating which behave better at the tribocorrosion tests were evaluated by means of RBS (Rutherford Backscattering Spectroscopy) IBA (Ion Beam Analysis) technique, using an alpha particles beam of 1.8 MeV, before and after the reciprocating motion in the tribocorrosion test. In order to simulate the elemental profile of the samples, the SIMNRA simulation computer code was used. Measurements of the adhesion of the coatings to the substrate were carried on by means of a scratch test using a tribometer. By taking micrographs of the produced tracks, the critical loads at which the coatings are fully separated from the substrate were determined. From these tests it was observed that a coating with 10 min of TiAlPtN in a TiAlPtN/TiAl period of 30 min in multilayers of 10 periods and with an average thickness of 145 nm for the TiAlPtN nanolayers had the best tribocorrosion resistance behavior, compared to that of the CoCrMo alloy. The RBS experiments showed a reduction of the thickness of the films along with some loss of the multilayer structure after the reciprocating motion. The adhesion tests indicated that the multilayer with the average TiAlPtN thickness of 145 nm displayed the highest critical load. These results indicate a high correlation between the adherence and the tribocorrosion behavior.

  10. Microstructure of Reaction Zone Formed During Diffusion Bonding of TiAl with Ni/Al Multilayer

    Science.gov (United States)

    Simões, Sónia; Viana, Filomena; Koçak, Mustafa; Ramos, A. Sofia; Vieira, M. Teresa; Vieira, Manuel F.

    2012-05-01

    In this article, the characterization of the interfacial structure of diffusion bonding a TiAl alloy is presented. The joining surfaces were modified by Ni/Al reactive multilayer deposition as an alternative approach to conventional diffusion bonding. TiAl substrates were coated with alternated Ni and Al nanolayers. The nanolayers were deposited by dc magnetron sputtering with 14 nm of period (bilayer thickness). Joining experiments were performed at 900 °C for 30 and 60 min with a pressure of 5 MPa. Cross sections of the joints were prepared for characterization of their interfaces by scanning electron microscopy (SEM), transmission electron microscopy (TEM), scanning transmission electron microscopy (STEM), high resolution TEM (HRTEM), energy dispersive x-ray spectroscopy (EDS), and electron backscatter diffraction (EBSD). Several intermetallic compounds form at the interface, assuring the bonding of the TiAl. The interface can be divided into three distinct zones: zone 1 exhibits elongated nanograins, very small equiaxed grains are observed in zone 2, while zone 3 has larger equiaxed grains. EBSD analysis reveals that zone 1 corresponds to the intermetallic Al2NiTi and AlNiTi, and zones 2 and 3 to NiAl.

  11. Al-quran dalam Perspektif Budaya

    OpenAIRE

    Sudrajat, Ajat

    2009-01-01

    Al-Quran merupakan kitab suci terakhir yang diturunkan kepada manusia. Tujuan utama diturunkannya al-Quran adalah sebagai kitab petunjuk yang meliputi bidang akidah, syariah, dan akhlak. Akan tetapi di luar ketiga petunjuk tersebut, al-Quran telah memberikan motivasi dan inspirasi kepada umat Islam dalam berbagai bidang kehidupan sehingga melahirkan jenis budaya tertentu. Dialog intelektual yang dilakukan secara kreatif oleh umat Islam terhadap al-Quran ternyata telah menghasilkan lahirnya ge...

  12. ITIJAHAT KAUN AL-NABI WA AL-RASUL FI SYAKHSIYAH MUHAMMAD FI NATSR MAULID AL-BARZANJI

    Directory of Open Access Journals (Sweden)

    Himmah Istomah

    2017-08-01

    Full Text Available One of human personalities is humanist. Based on the understanding of Maslow’s theory of motivation, researcher seeks to uncover kinds of motivational needs of Muhammad Saw contained in Maulid Al-Barzanjiy (the work of Ja 'far bin Hasan al-Barzanji (d. 1763 M. The goal is realized through a descriptive qualitative approach with  text analysis  about Psycholiterature of Endraswara. The results of this study indicate that in Maulid Al-Barzanji there are Muhammad Saw’s five needs and how their satisfying perfectly,  namely: physiological needs, safety, social, esteem, and self-actualization. Thus, it can be interpreted that Muhammad SAW as an ordinary human having motivational needs. His prophetic and apostleship honor is not a direct blessing from Allah, but he had been through some complicated processes in life. This can be applied by his followers, so they can complete their motivational needs to reach the satiation as a caliph and to be useful person in this world.

  13. Microstructure and bonding mechanism of Al/Ti bonded joint using Al-10Si-1Mg filler metal

    International Nuclear Information System (INIS)

    Sohn, Woong H.; Bong, Ha H.; Hong, Soon H.

    2003-01-01

    The microstructures and liquid state diffusion bonding mechanism of cp-Ti to 1050 Al using an Al-10.0wt.%Si-1.0wt.%Mg filler metal with 100 μm in thickness have been investigated at 620 deg. C under 1x10 -4 Torr. The effects of bonding process parameters on microstructure of bonded joint have been analyzed by using an optical microscope, AES, scanning electron microscopy and EDS. The interfacial bond strength of Al/Ti bonded joints was measured by the single lap shear test. The results show that the bonding at the interface between Al and filler metal proceeds by wetting the Al with molten filler metal, and followed by removal of oxide layer on surface of Al. The interface between Al and filler metal moved during the isothermal solidification of filler metal by the diffusion of Si from filler metal into Al layer. The interface between Al and filler metal became curved in shape with increasing bonding time due to capillary force at grain boundaries. The bonding at the interface between Ti and filler metal proceeds by the formation of two different intermetallic compound layers, identified as Al 5 Si 12 Ti 7 and Al 12 Si 3 Ti 5 , followed by the growth of the intermetallic compound layers. The interfacial bond strength at Al/Ti joint increased with increasing bonding time up to 25 min at 620 deg. C. However, the interfacial bond strength of Al/Ti joint decreased after bonding time of 25 min at 620 deg. C due to formation of cavities in Al near Al/intermetallic interfaces

  14. Micromechanisms of fracture and fatigue in Ti3Al based and TiAl based intermetallics

    International Nuclear Information System (INIS)

    James, A.W.; Chave, R.A.; Hippsley, C.A.; Bowen, P.

    1993-01-01

    Micromechanisms of fracture and fatigue crack growth resistance in specific Ti 3 Al based and TiAl based intermetallics are reviewed. Effects of test temperature, environment and microstructure on crack growth resistance are considered in detail for several Ti 3 Al and Ti'Al based intermetallic systems under development. The implications of these studies for the structural reliability of these materials is also addressed briefly. (orig.)

  15. Core electron binding energy shifts of AlBr3 and Al2Br6 vapor

    International Nuclear Information System (INIS)

    Mueller, Astrid M.; Plenge, Juergen; Leone, Stephen R.; Canton, Sophie E.; Rude, Bruce S.; Bozek, John D.

    2006-01-01

    The Al 2p and Br 3d inner-shell photoelectron spectra of aluminum tribromide monomer and dimer vapor were measured at 90 and 95 eV photon energy, respectively, to determine the core electron binding energies of the atoms in the two molecular species. While AlBr 3 has three identical Br atoms, Al 2 Br 6 exhibits four terminal and two bridging Br atoms. The species are identified by their distinct valence photoelectron spectra. Comparison of the observed Al 2p 1/2 and Al 2p 3/2 electron binding energies of AlBr 3 with those of Al 2 Br 6 shows that there is a chemical shift of (0.15 ± 0.03) eV to lower energy in the dimer. In Al 2 Br 6 , an assignment is proposed in which the Br 3d 3/2 and Br 3d 5/2 binding energies of terminal Br atoms are (1.18 ± 0.03) eV lower than those of bridging Br atoms. This assignment assumes that both types of Br atoms have similar cross-sections for ionization. With this result, the Br 3d 3/2 and Br 3d 5/2 binding energies of Br atoms in AlBr 3 are (0.81 ± 0.03) eV lower than those of bridging Br atoms of the dimer but (0.37 ± 0.03) eV higher than those of terminal Br atoms of the dimer. The obtained chemical shifts are considered in terms of the binding relations and electron density distributions in both molecules. Chemical shifts that are larger than a few hundred millielectron volts, as observed in the Al 2 Br 6 /AlBr 3 system, offer potential to study the dissociation dynamics of the dimer in a femtosecond visible or ultraviolet-pump/XUV-probe experiment

  16. PENDEKATAN HERMENEUTIK DALAM PEMAHAMAN HADIS (Kajian Kitab Fath al-Bari Karya Ibn Hajar Al-‘Asqalani

    Directory of Open Access Journals (Sweden)

    Agusni Yahya

    2014-12-01

    Full Text Available The hadith explanation book of Sahih al-Bukhari written by Ibn Hajar Al-‘Asqalani, Fath al-Bari, is one of the most pupular books in Moslem ummah. Is widely used by Moslem scholars to meet the meanings of hadiths compiled by the imam al-Bukhari in his Sahih al-Bukhari. Fath al-Bari is considered significant to do the research on it in order to develop the science of hadith, mainly through the hermeneutic method. By using this method, the research questions are: 1. How does Ibn Hajar Al-‘Asqalani explain the matans (hadith texts of Sahih al Bukhari in connection with hermeneutic method? 2. What are the hermeneutic principles used by Ibn Hajar Al-‘Asqalani in his explanations of hadith? This research is expected to respond the research questions above so that it can be implimented the field of hadith in relation to develop hadith methodology. Finally, the research uncover that in his explanations of hadiths,  Ibn Hajar Al-‘Asqalani is oriented his world views to the classical Islam, the era of Prophet’s companions and their successors, the Salaf al-Salih. He does not express the Islamic world issues available in his time in his explanations of the hadiths. He is considered a normative ‘ulama since he is not influenced by the emerging cases situated his time in Egypt, Mecca and Madina. He tends to be textual to explain the matans of hadiths although to some extent he uncovers the historical contexts of the hadiths he explains. This is common for a muhadith  whose main jobs is to collect and narrate the whole data on Prophet's sayings, acts and permissions either on sanads (narrators or matans (texts.Keywords:  Fath al-Bari; sharh al-hadith; hermeneutik.

  17. Thermophysical properties of αAl2O3, MgAl2O4 and AlN at low tempertures

    International Nuclear Information System (INIS)

    Burghartz, S.

    1995-12-01

    A possibility for producing energy in future might be the nuclear fusion. The process of nuclear fusion is characterized by melting nuclei of hydrogen atoms (deuterium and tritium) which yield to the production of helium atom nuclei. For this process extremely high temperatures of the deuterium-tritium-gas plasma are necessary. The additional heating of the plasma by microwaves requires materials with low diaelectric losses and high thermal conductivity. The thermal conductivity can be increased by cooling the windows which lead to the plasma chambre. Experimental investigations with the aim to check the influence of liquid nitrogen (T=70 K) on the cooling of the windows were performed in the temperature region 70 K 2 O 3 , MgAl 2 O 4 and AlN were measured. The thermal conductivity can be calculated using the equation λ=αc p ρ λ=thermal conductivity α=thermal diffusivity c p =specific heat (at constant pressure) ρ=density. Furthermore a theoretical method to calculate the thermal conductivity at low temperatures is presented; this is done by using a model modification of heat transport in electric insulators. As result the influence of intrinsic parameters (crystal structure, interatomar binding, anharmonicity) and extrinsic parameters (point defects, dislocations, boundary areas) upon thermal conductivity of α-Al 2 O 3 , MgAl 2 O 4 and AlN are achieved. (orig.)

  18. Grain refinement of Al wrought alloys with newly developed AlTiC master alloys; Kornfeinung von Al-Knetlegierungen mit neu entwickelten AlTiC-Vorlegierungen

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, W. [Vereinigte Aluminium-Werke AG, Bonn (Germany). Forschung und Entwicklung

    2000-10-01

    AlTiC master alloys are a new grain refiner type to produce an equiaxed grain structure of cast extrusion and rolling ingots. These master alloys contain Ti carbides which act as nucleants of the {alpha} solid solution during solidification. The TiC content is lower than the TiB{sub 2} content of the industrial proved AlTiB master alloys. Benefits of the AlTiC master alloys are the low agglomeration tendency of the Ti carbides in the melt and that no Zr poisoning takes place. Despite of the low Ti carbide content the grain refinement performance can be very efficient, if low melt temperatures during casting will be used and as result of this a sufficient constitutional supercooling at the solidification front is achieved. (orig.)

  19. Advanced life support (ALS) instructors experience of ALS education in Western Australia: a qualitative exploratory research study.

    Science.gov (United States)

    Taplin, John; McConigley, Ruth

    2015-04-01

    When cardiac arrest occurs, timely competent advanced life support (ALS) interventions by nursing staff can influence patient outcomes. Ongoing ALS education influences maintenance of competency and avoids skill decay. To explore the methods of ALS education delivery for nurses in the workplace; describe the issues relating to maintaining ALS competency; explore ALS competency decay for nurses and develop recommendations for the provision of continuing ALS education. A qualitative exploratory design was used to study ALS education provision in the workplace. Data were collected from ALS nurse experts in Western Australia by face-to-face and phone interviews. Semi-structured interviews were conducted and organised around a set of predetermined questions. Two major themes were identified; the first theme Demand and Supply describes the increasing demand for ALS education for nurses and the challenges with providing timely cost effective traditional face-to-face ALS education. The second theme, Choosing The Best Education Options describes new ways to provide ALS education using emerging technologies. The study suggested that using e-learning methods would assist with educating the maximum amount of nurses in a timely manner and e-learning and teleconferencing offer opportunities to reach nurses in distant locations. Delivering ALS education more frequently than annually would increase skills maintenance and lessen skill decay. Further research is required to explore which blended e-learning model is best suited to ALS education. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Al-Qaeda-Syria (AQS): An Al-Qaeda Affiliate Case Study

    Science.gov (United States)

    2017-10-01

    Special Operations/Low Intensity Conflict CT Counterterrorism FF Foreign Fighter FSA Free Syrian Army GEC Global Engagement Center HTS Hay’at...war as an opportunity for the global jihadist movement, an opportunity that paralleled the one Iraq had offered a decade earlier.11 He was initially...Zawahiri’s vision of Al-Qaeda franchises oriented toward winning popular support. When al-Zawahiri published his “General Guidelines for Jihad” in

  1. Mechanochemical synthesis of Cu-Al and methyl orange intercalated Cu-Al layered double hydroxides

    International Nuclear Information System (INIS)

    Qu, Jun; He, Xiaoman; Chen, Min; Hu, Huimin; Zhang, Qiwu; Liu, Xinzhong

    2017-01-01

    In this study, a mechanochemical route to synthesize a Cu-Al layered double hydroxide (LDH) and a methyl orange (MO) intercalated one (MO-LDH) was introduced, in which basic cupric carbonate (Cu_2(OH)_2CO_3) and aluminum hydroxide (Al(OH)_3) with Cu/Al molar ratio at 2/1 was first dry ground for 2 h and then agitated in water or methyl orange solution for another 4 h to obtain the LDH and MO-LDH products without any heating operation. The prepared samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Thermogravimetry (TG), Differential scanning calorimetry (DSC) and Scanning electron microscopy (SEM). The products showed high crystallinity phase of Cu-Al and MO intercalated Cu-Al LDH with no evident impurities, proving that the craft introduced here was facile and effective. The new idea can be applied in other fields to produce organic-inorganic composites. - Highlights: • A facile mechanochemical route to synthesize Cu-Al and MO intercalated Cu-Al LDH. • The products possesses high crystalline of LDH phase with no impure phases. • The dry milling process induces the element substitution between the raw materials. • The agitation operation helps the grain growth of LDH.

  2. Mechanochemical synthesis of Cu-Al and methyl orange intercalated Cu-Al layered double hydroxides

    Energy Technology Data Exchange (ETDEWEB)

    Qu, Jun, E-mail: forsjun@whut.edu.cn [School of Resources and Environmental Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei 430070 (China); He, Xiaoman; Chen, Min; Hu, Huimin [School of Resources and Environmental Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei 430070 (China); Zhang, Qiwu, E-mail: zhangqw@whut.edu.cn [School of Resources and Environmental Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei 430070 (China); Liu, Xinzhong [College of Ecological Environment and Urban Construction, Fujian University of Technology, Fuzhou 350118 China (China)

    2017-04-15

    In this study, a mechanochemical route to synthesize a Cu-Al layered double hydroxide (LDH) and a methyl orange (MO) intercalated one (MO-LDH) was introduced, in which basic cupric carbonate (Cu{sub 2}(OH){sub 2}CO{sub 3}) and aluminum hydroxide (Al(OH){sub 3}) with Cu/Al molar ratio at 2/1 was first dry ground for 2 h and then agitated in water or methyl orange solution for another 4 h to obtain the LDH and MO-LDH products without any heating operation. The prepared samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Thermogravimetry (TG), Differential scanning calorimetry (DSC) and Scanning electron microscopy (SEM). The products showed high crystallinity phase of Cu-Al and MO intercalated Cu-Al LDH with no evident impurities, proving that the craft introduced here was facile and effective. The new idea can be applied in other fields to produce organic-inorganic composites. - Highlights: • A facile mechanochemical route to synthesize Cu-Al and MO intercalated Cu-Al LDH. • The products possesses high crystalline of LDH phase with no impure phases. • The dry milling process induces the element substitution between the raw materials. • The agitation operation helps the grain growth of LDH.

  3. Superstructure formation in PrNi_2Al_3 and ErPd_2Al_3

    International Nuclear Information System (INIS)

    Eustermann, Fabian; Hoffmann, Rolf-Dieter; Janka, Oliver; Oldenburg Univ.

    2017-01-01

    The intermetallic phase ErPd_2Al_3 was obtained by arc-melting of the elements and subsequent annealing for crystal growth. The sample was studied by X-ray diffraction on powders and single crystals. The structure of ErPd_2Al_3 was refined from X-ray diffraction data and revealed a superstructure of PrNi_2Al_3 - a CaCu_5 derivative (P6/m, a=1414.3(1), c=418.87(3) pm wR=0.0820, 1060 F"2 values, 48 variables). The same superstructure was subsequently found for PrNi_2Al_3 (P6/m, a=1407.87(4), c=406.19(2) pm, wR=0.0499, 904 F"2 values, 47 variables). In the crystal structure, the aluminium and transition metal atoms form a polyanionic network according to [T_2Al_3]"δ"-, while rare earth atoms fill cavities within the networks. They are coordinated by six transition metal and twelve aluminum atoms. In contrast to the PrNi_2Al_3 type structure reported so far, two crystallographic independent rare-earth sites are found of which one (1b) is shifted by 1/2 z, causing a distortion in the structure along with a recoloring of the T and Al atoms in the network.

  4. 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...

  5. Deformation mechanisms of nanotwinned Al

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xinghang [Texas A & M Univ., College Station, TX (United States)

    2016-11-10

    The objective of this project is to investigate the role of different types of layer interfaces on the formation of high density stacking fault (SF) in Al in Al/fcc multilayers, and understand the corresponding deformation mechanisms of the films. Stacking faults or twins can be intentionally introduced (via growth) into certain fcc metals with low stacking fault energy (such as Cu, Ag and 330 stainless steels) to achieve high strength, high ductility, superior thermal stability and good electrical conductivity. However it is still a major challenge to synthesize these types of defects into metals with high stacking fault energy, such as Al. Although deformation twins have been observed in some nanocrystalline Al powders by low temperature, high strain rate cryomilling or in Al at the edge of crack tip or indentation (with the assistance of high stress intensity factor), these deformation techniques typically introduce twins sporadically and the control of deformation twin density in Al is still not feasible. This project is designed to test the following hypotheses: (1) Certain type of layer interfaces may assist the formation of SF in Al, (2) Al with high density SF may have deformation mechanisms drastically different from those of coarse-grained Al and nanotwinned Cu. To test these hypotheses, we have performed the following tasks: (i) Investigate the influence of layer interfaces, stresses and deposition parameters on the formation and density of SF in Al. (ii) Understand the role of SF on the deformation behavior of Al. In situ nanoindentation experiments will be performed to probe deformation mechanisms in Al. The major findings related to the formation mechanism of twins and mechanical behavior of nanotwinned metals include the followings: 1) Our studies show that nanotwins can be introduced into metals with high stacking fault energy, in drastic contrast to the general anticipation. 2) We show two strategies that can effectively introduce growth twins in

  6. Deformation mechanisms of nanotwinned Al

    International Nuclear Information System (INIS)

    Zhang, Xinghang

    2016-01-01

    The objective of this project is to investigate the role of different types of layer interfaces on the formation of high density stacking fault (SF) in Al in Al/fcc multilayers, and understand the corresponding deformation mechanisms of the films. Stacking faults or twins can be intentionally introduced (via growth) into certain fcc metals with low stacking fault energy (such as Cu, Ag and 330 stainless steels) to achieve high strength, high ductility, superior thermal stability and good electrical conductivity. However it is still a major challenge to synthesize these types of defects into metals with high stacking fault energy, such as Al. Although deformation twins have been observed in some nanocrystalline Al powders by low temperature, high strain rate cryomilling or in Al at the edge of crack tip or indentation (with the assistance of high stress intensity factor), these deformation techniques typically introduce twins sporadically and the control of deformation twin density in Al is still not feasible. This project is designed to test the following hypotheses: (1) Certain type of layer interfaces may assist the formation of SF in Al, (2) Al with high density SF may have deformation mechanisms drastically different from those of coarse-grained Al and nanotwinned Cu. To test these hypotheses, we have performed the following tasks: (i) Investigate the influence of layer interfaces, stresses and deposition parameters on the formation and density of SF in Al. (ii) Understand the role of SF on the deformation behavior of Al. In situ nanoindentation experiments will be performed to probe deformation mechanisms in Al. The major findings related to the formation mechanism of twins and mechanical behavior of nanotwinned metals include the followings: 1) Our studies show that nanotwins can be introduced into metals with high stacking fault energy, in drastic contrast to the general anticipation. 2) We show two strategies that can effectively introduce growth twins in

  7. Study on Microstructure and Mechanical Properties of Hypereutectic Al-18Si Alloy Modified with Al-3B.

    Science.gov (United States)

    Gong, Chunjie; Tu, Hao; Wu, Changjun; Wang, Jianhua; Su, Xuping

    2018-03-20

    An hypereutectic Al-18Si alloy was modified via an Al-3B master alloy. The effect of the added Al-3B and the modification temperature on the microstructure, tensile fracture morphologies, and mechanical properties of the alloy were investigated using an optical microscope, Image-Pro Plus 6.0, a scanning electron microscope, and a universal testing machine. The results show that the size of the primary Si and its fraction decreased at first, and then increased as an additional amount of Al-3B was added. When the added Al-3B reached 0.2 wt %, the fraction of the primary Si in the Al-18Si alloy decreased with an increase in temperature. Compared with the unmodified Al-18Si alloy, the tensile strength and elongation of the alloy modified at 850 °C with 0.2 wt % Al-3B increased by 25% and 81%, respectively. The tensile fracture of the modified Al-18Si alloy exhibited partial ductile fracture characteristics, but there were more areas with ductile characteristics compared with that of the unmodified Al-18Si alloy.

  8. 26Mg(p,n)26Al and 23Na(α,n)26Al reactions

    International Nuclear Information System (INIS)

    Skelton, R.T.

    1985-01-01

    Cross sections for the 26 Mg(p,n) 26 Al reaction were measured from threshold at 4.988 MeV to 5.820 MeV. Cross sections for the 23 Na(α,n) 26 Al reaction were measured from threshold at 3.483 MeV to 4.597 MeV. In each case, separate measurements were to the ground state and to the first and second excited states of 26 Al. Cross sections for the inverse reactions were calculated and reaction rate factors relating to the destruction of 26 Al in a supernova environment were determined. Astrophysical implications relating to the observation of live and extinct 26 Al are discussed. Excitation functions for several additional exit channels for the 26 Mg + rho and 23 Na + α reactions are reported

  9. effect of the parameters of AlN/GaN/AlGaN and AlN/GaN/InAlN heterostructures with a two-dimensional electron gas on their electrical properties and the characteristics of transistors on their basis

    Energy Technology Data Exchange (ETDEWEB)

    Tsatsulnikov, A. F., E-mail: andrew@beam.ioffe.ru [Russian Academy of Sciences, Submicron Heterostructures for Microelectronics Research and Engineering Center (Russian Federation); Lundin, V. W.; Zavarin, E. E.; Yagovkina, M. A.; Sakharov, A. V. [Russian Academy of Sciences, Ioffe Physical–Technical Institute (Russian Federation); Usov, S. O. [Russian Academy of Sciences, Submicron Heterostructures for Microelectronics Research and Engineering Center (Russian Federation); Zemlyakov, V. E.; Egorkin, V. I. [National Research University of Electronic Technology (MIET) (Russian Federation); Bulashevich, K. A.; Karpov, S. Yu. [“Soft-Impact” Ltd. (Russian Federation); Ustinov, V. M. [Russian Academy of Sciences, Submicron Heterostructures for Microelectronics Research and Engineering Center (Russian Federation)

    2016-10-15

    The effect of the layer thickness and composition in AlGaN/AlN/GaN and InAlN/AlN/GaN transistor heterostructures with a two-dimensional electron gas on their electrical and the static parameters of test transistors fabricated from such heterostructures are experimentally and theoretically studied. It is shown that the use of an InAlN barrier layer instead of AlGaN results in a more than twofold increase in the carrier concentration in the channel, which leads to a corresponding increase in the saturation current. In situ dielectric-coating deposition on the InAlN/AlN/GaN heterostructure surface during growth process allows an increase in the maximum saturation current and breakdown voltages while retaining high transconductance.

  10. Fabrication and thermal characterization of amorphous and nanocrystalline Al{sub 9}FeNi/Al{sub 3}Ti compound

    Energy Technology Data Exchange (ETDEWEB)

    Tavoosi, Majid, E-mail: ma.tavoosi@gmail.com

    2017-01-15

    In this study, the fabrication and structural characterization of amorphous/nanocrystalline Al{sub 9}FeNi/Al{sub 3}Ti phase has been performed. In this regards, milling and annealing processes were applied on Al{sub 80}Fe{sub 10}Ti{sub 5}Ni{sub 5} (at. %) powder mixture for different periods of time. The prepared samples were characterized using X-ray diffraction (XRD), scanning and transmission electron microscopy (SEM and TEM) and differential scanning calorimetery (DSC). According to the results, supersaturated solid solution, nanocrystalline Al{sub 9}FeNi/Al{sub 3}Ti (with average crystallite size of about 7 nm) and amorphous phases indicated three different microstructures which can be formed in Al{sub 80}Fe{sub 10}Ti{sub 5}Ni{sub 5} system during milling process. The formed supersaturated solid solution and amorphous phases were unstable and transformed to Al{sub 9}FeNi/Al{sub 3}Ti intermetallic compound during annealing process. It is shown that, Al{sub 9}FeNi phase in Al{sub 9}FeNi/Al{sub 3}Ti intermetallic compound can decompose into Al{sub 3}Ni, Al{sub 13}Fe{sub 4} and liquid phases during a reversible peritectic reaction at 809 °C. - Highlights: • We study the effect of milling process on Al{sub 80}Fe{sub 10}Ti{sub 5}Ni{sub 5} alloy. • We study the effect of annealing on Al{sub 80}Fe{sub 10}Ti{sub 5}Ni{sub 5} supersaturated solid solution phase. • We study the effect of annealing on Al{sub 80}Fe{sub 10}Ti{sub 5}Ni{sub 5} amorphous phase. • We study the thermal behaviour of Al{sub 9}FeNi/Al{sub 3}Ti compound.

  11. Computer aided cooling curve analysis for Al-5Si and Al-11Si alloys ...

    African Journals Online (AJOL)

    The effect of grain refiner, modifier, and combination of grain refiner cum modifier was studied on Al-5Si and Al-11Si alloys using computer aided cooling curve analysis. For combined grain refinement and modification effect, Al-Ti-B-Sr single master alloy was developed that acted as both grain refiner and modifier.

  12. 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 project...

  13. Gd3+-ESR and magnetic susceptibility of GdCu4Al8 and GdMn4Al8

    International Nuclear Information System (INIS)

    Coldea, R.; Coldea, M.; Pop, I.

    1994-01-01

    Gd ESR of GdCu 4 Al 8 and GdMn 4 Al 8 and magnetic susceptibility of GdCu 4 Al 8 , GdMn 4 Al 8 , and YMn 4 Al 8 were measured in the temperature range of 290K--460K and 90K--1050K, respectively. The occurrence of the Mn moment in YMn 4 Al 8 and GdMn 4 Al 8 is strongly correlated with the critical value of d∼2.6 angstrom of the Mn-Mn distance below which the Mn moment is not stable. The experimental data for GdMn 4 Al 8 , compared with the data for the isostructural compounds GdCu 4 Al 8 and YMn 4 Al 8 , show that near the critical value of d, the existence of Mn moment depends not only on the value of d, but also on the local magnetic surroundings. It has been revealed that the magnetic character of Mn moment in YMn 4 Al 8 and GdMn 4 Al 8 changes from an itinerant electron type to a local-moment type with increasing temperature

  14. Effect of AlB2-Mg interaction on the mechanical properties of Al-based composites

    International Nuclear Information System (INIS)

    Calderon, Hermes E.; Hidalgo, Ruth G.I.; Melgarejo, Z. Humberto; Suarez, O. Marcelo

    2010-01-01

    A series of Al-based composites with a matrix containing 2.5 wt.%Cu and 1 wt.%Mg, and reinforced with Al diborides was manufactured and characterized via microscopy and mechanical testing. The impact resistance of the composites revealed interaction between AlB 2 dispersoids and Mg originally present in the Al matrix. An unexpected increase in the absorbed impact energy of composites with diborides prompted complementary experiments leading to this finding. Hardness tests were correlated to those results and provided further evidence of the interaction between Mg and the dispersoids. Additional energy dispersive spectroscopy (EDS) analysis and X-ray diffraction tests supported with crystal modeling demonstrated that Mg effectively diffused into the AlB 2 crystal producing a doped structure with an Al 1-x Mg x B 2 formula where x lies between 0.08 and 0.15.

  15. Potential skin involvement in ALS: revisiting Charcot's observation - a review of skin abnormalities in ALS.

    Science.gov (United States)

    Paré, Bastien; Gros-Louis, François

    2017-07-26

    Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease affecting motor neurons of the brain and spinal cord, leading to progressive paralysis and death. Interestingly, many skin changes have been reported in ALS patients, but never as yet fully explained. These observations could be due to the common embryonic origin of the skin and neural tissue known as the ectodermal germ layer. Following the first observation in ALS patients' skin by Dr Charcot in the 19th century, in the absence of bedsores unlike other bedridden patients, other morphological and molecular changes have been observed. Thus, the skin could be of interest in the study of ALS and other neurodegenerative diseases. This review summarizes skin changes reported in the literature over the years and discusses about a novel in vitro ALS tissue-engineered skin model, derived from patients, for the study of ALS.

  16. Effects of O in a binary-phase TiAl-Ti3Al alloy: from site occupancy to interfacial energetics

    International Nuclear Information System (INIS)

    Wei Ye; Xu Huibin; Zhou Hongbo; Zhang Ying; Lu Guanghong

    2011-01-01

    We have investigated site occupancy and interfacial energetics of a TiAl-Ti 3 Al binary-phase system with O using a first-principles method. Oxygen is shown to energetically occupy the Ti-rich octahedral interstitial site, because O prefers to bond with Ti rather than Al. The occupancy tendency of O in TiAl alloy from high to low is α 2 -Ti 3 Al to the γ-α 2 interface and γ-TiAl. We demonstrate that O can largely affect the mechanical properties of the TiAl-Ti 3 Al system. Oxygen at the TiAl-Ti 3 Al interface reduces both the cleavage energy and the interface energy, and thus weakens the interface strength but strongly stabilizes the TiAl/Ti 3 Al interface with the O 2 molecule as a reference. Consequently, the mechanical property variation of TiAl alloy due to the presence of O not only depends on the number of TiAl/Ti 3 Al interfaces but also is related to the O concentration in the alloy.

  17. A study on wear resistance and microcrack of the Ti{sub 3}Al/TiAl + TiC ceramic layer deposited by laser cladding on Ti-6Al-4V alloy

    Energy Technology Data Exchange (ETDEWEB)

    Li Jianing, E-mail: ljnljn1022@163.com [Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education), Department of Materials Science, Shandong University, Jing Shi Road 17923, Jinan 250061, Shandong (China); Chen Chuanzhong [Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials, Ministry of Education, Department of Materials Science, Shandong University, Jing Shi Road 17923, Jinan 250061, Shandong (China); Squartini, Tiziano [INFM-Department of Physics, Siena University, Siena 53100 (Italy); He Qingshan [Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials, Ministry of Education, Department of Materials Science, Shandong University, Jing Shi Road 17923, Jinan 250061, Shandong (China)

    2010-12-15

    Laser cladding of the Al + TiC alloy powder on Ti-6Al-4V alloy can form the Ti{sub 3}Al/TiAl + TiC ceramic layer. In this study, TiC particle-dispersed Ti{sub 3}Al/TiAl matrix ceramic layer on the Ti-6Al-4V alloy by laser cladding has been researched by means of X-ray diffraction, scanning electron microscope, electron probe micro-analyzer, energy dispersive spectrometer. The main difference from the earlier reports is that Ti{sub 3}Al/TiAl has been chosen as the matrix of the composite coating. The wear resistance of the Al + 30 wt.% TiC and the Al + 40 wt.% TiC cladding layer was approximately 2 times greater than that of the Ti-6Al-4V substrate due to the reinforcement of the Ti{sub 3}Al/TiAl + TiC hard phases. However, when the TiC mass percent was above 40 wt.%, the thermal stress value was greater than the materials yield strength limit in the ceramic layer, the microcrack was present and its wear resistance decreased.

  18. Synthesis behavior of nanocrystalline Al-Al2O3 composite during low time mechanical milling process

    International Nuclear Information System (INIS)

    Alizadeh, Mostafa; Aliabadi, Morteza Mirzaei

    2011-01-01

    Research highlights: → In the low time milling the effect of Al 2 O 3 amount is investigated → Al 2 O 3 particles are distributed uniformly in the Al matrix → In the low time milling it is possible to produce nanostructured composite powder → Median size and bulk density measurements demonstrate reaching the steady state. - Abstract: In this work, four different volume fractions of Al 2 O 3 (10, 20, 30 and 40 vol.%) were mixed with the fine Al powder and the powder blends were milled for 5 h. Scanning electron microscopy analysis, particle size analysis and bulk density measurements were used to investigate the morphological changes and achieving the steady state conditions. The results showed that increasing the Al 2 O 3 content can provide the steady state particle size in 5 h milling process. It was found that increasing the volume fraction of Al 2 O 3 leads to increasing the uniformity of Al 2 O 3 . Standard deviations of microhardness measurements confirmed this result. The XRD pattern and XRF investigations depicted that increasing the Al 2 O 3 content causes an increase in the crystal defects, micro-strain and Fe contamination during 5 h milling process of nanocrystalline composite powders while the grain size is decreased. To investigate the effect of milling time, Al-30 vol.% Al 2 O 3 (which achieved steady state during 5 h milling process) was milled for 1-4 h. The results depicted that the milling time lower than 5 h, do not achieve to steady state conditions.

  19. Study of the ternary alloy systems Al-Ni-Fe and Al-Cu-Ru with special regard to quasicrystalline phases

    International Nuclear Information System (INIS)

    Lemmerz, U.

    1996-07-01

    Two ternary alloy-systems, the Al-Ni-Fe system and the Al-Cu-Ru system were studied with special regard to quasicrystalline phases. Isothermal sections were established in both systems in the stoichiometric area of the quasicrystalline phase. In the Al-Ni-Fe system a new stable decagonal phase was found. Its stoichiometric range is very small around Al 71.6 Ni 23.0 Fe 5.4 . The temperature range in which it is stable lies between 847 and 930 C. The decagonal phase undergoes a eutectoid reaction to the three crystalline phases Al 3 Ni 2 , Al 3 Ni and Al 13 Fe 4 at 847 C. It melts peritectically at 930 C forming Al 13 Fe 4 , Al 3 Ni 2 and a liquid. The investigations in the Al-Cu-Ru system concentrated on the phase equilibria between the icosahedral phase and its neighbouring phases in a temperature range between 600 and 1000 C. The icosahedral phase was observed in the whole temperature range. The investigated stoichiometric area extends down to Al contents of 45%, which allows the fields of existence to be determined for the ternary phases α-AlCuRu, the icosahedral phase and Al 7 Cu 2 Ru. Binary phases were determined down to the upper (high Al content) border of AlRu. No hitherto unknown phase was observed in the investigated area. Rietveld analyses were carried out on α-AlCuRu and Al 7 Cu 2 Ru showing some discrepancies from the α-AlMnSi structure taken as a base for α-AlCuRu and confirming the Al 7 Cu 2 Fe structure for Al 7 Cu 2 Ru. (orig.)

  20. Al-Cu-Li and Al-Mg-Li alloys: Phase composition, texture, and anisotropy of mechanical properties (Review)

    Science.gov (United States)

    Betsofen, S. Ya.; Antipov, V. V.; Knyazev, M. I.

    2016-04-01

    The results of studying the phase transformations, the texture formation, and the anisotropy of the mechanical properties in Al-Cu-Li and Al-Mg-Li alloys are generalized. A technique and equations are developed to calculate the amounts of the S1 (Al2MgLi), T1 (Al2CuLi), and δ' (Al3Li) phases. The fraction of the δ' phase in Al-Cu-Li alloys is shown to be significantly higher than in Al-Mg-Li alloys. Therefore, the role of the T1 phase in the hardening of Al-Cu-Li alloys is thought to be overestimated, especially in alloys with more than 1.5% Li. A new model is proposed to describe the hardening of Al-Cu-Li alloys upon aging, and the results obtained with this model agree well with the experimental data. A texture, which is analogous to that in aluminum alloys, is shown to form in sheets semiproducts made of Al-Cu-Li and Al-Mg-Li alloys. The more pronounced anisotropy of the properties of lithium-containing aluminum alloys is caused by a significant fraction of the ordered coherent δ' phase, the deformation mechanism in which differs radically from that in the solid solution.

  1. 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.

  2. Strain Balanced AlGaN/GaN/AlGaN nanomembrane HEMTs.

    Science.gov (United States)

    Chang, Tzu-Hsuan; Xiong, Kanglin; Park, Sung Hyun; Yuan, Ge; Ma, Zhenqiang; Han, Jung

    2017-07-25

    Single crystal semiconductor nanomembranes (NM) are important in various applications such as heterogeneous integration and flexible devices. This paper reports the fabrication of AlGaN/GaN NMs and NM high electron mobility transistors (HEMT). Electrochemical etching is used to slice off single-crystalline AlGaN/GaN layers while preserving their microstructural quality. A double heterostructure design with a symmetric strain profile is employed to ensure minimal residual strain in freestanding NMs after release. The mobility of the two-dimensional electron gas (2DEG), formed by the AlGaN/GaN heterostructure, is noticeably superior to previously reported values of many other NMs. AlGaN/GaN nanomembrane HEMTs are fabricated on SiO 2 and flexible polymeric substrates. Excellent electrical characteristics, including a high ON/OFF ratio and transconductance, suggest that III-Nitrides nanomembranes are capable of supporting high performance applications.

  3. Validated thermodynamic prediction of AlP and eutectic (Si) solidification sequence in Al-Si cast alloys

    International Nuclear Information System (INIS)

    Liang, S M; Schmid-Fetzer, R

    2016-01-01

    The eutectic microstructure in hypoeutectic Al-Si cast alloys is strongly influenced by AlP particles which are potent nuclei for the eutectic (Si) phase. The solidification sequence of AlP and (Si) phases is, thus, crucial for the nucleation of eutectic silicon with marked impact on its morphology. This study presents this interdependence between Si- and P-compositions, relevant for Al-Si cast alloys, on the solidification sequence of AlP and (Si). These data are predicted from a series of thermodynamic calculations. The predictions are based on a self-consistent thermodynamic description of the Al-Si-P ternary alloy system developed recently. They are validated by independent experimental studies on microstructure and undercooling in hypoeutectic Al-Si alloys. A constrained Scheil solidification simulation technique is applied to predict the undercooling under clean heterogeneous nucleation conditions, validated by dedicated experimental observations on entrained droplets. These specific undercooling values may be very large and their quantitative dependence on Si and P content of the Al alloy is presented. (paper)

  4. Phase diagrams of aluminium alloys of Al-Cu-Mg, Al-Mg-Si-Cu, and Al-Mg-Li system

    International Nuclear Information System (INIS)

    Ber, L.B.; Kaputkin, E.Ya.

    2001-01-01

    Isothermal diagrams of phase transformations (DPT) and temperature-time charts (TTC) of variation of electric conductivity and of mechanical features at tension were plotted following thermal treatment according to the pattern of direct hardening and ageing and according to the pattern of normal aging for D16 commercial alloy, Al-Cu-Mg model alloy of the same system, AD37 commercial alloys of Al-Mg-Si-Cu and 1424 one of Al-Li-Mg system. Phase transformations were studied by means of fluorescence electron microscopy, micro-X-ray spectral analysis, X-ray phase analysis of single crystals and polycrystals and differential scanning calorimetry. For every alloy comparison of TTC and DPT enables to clarity the mechanism of phase composition effect on features and to optimize conditions of hardening cooling and ageing [ru

  5. Superhydrophobic ZnAl double hydroxide nanostructures and ZnO films on Al and glass substrates

    Energy Technology Data Exchange (ETDEWEB)

    De, Debasis, E-mail: debasis.de@bcrec.ac.in [Electronics and Instrumentation Engineering Department, Dr. B C Roy Engineering College, Durgapur, West Bengal 713206 (India); Sarkar, D.K. [Centre Universitaire de Recherche sur l' Aluminium (CURAL), L' Université du Québec à Chicoutimi, 555 Blvd. Université, Chicoutimi, Saguenay, Québec G7H 2B1 (Canada)

    2017-01-01

    Superhydrophobic nanostructured ZnAl: layered double hydroxides (LDHs) and ZnO films have been fabricated on Al and glass substrates, respectively, by a simple and cost effective chemical bath deposition technique. Randomly oriented hexagonal patterned of ZnAl: LDHs thin nanoplates are clearly observed on Al-substrate in the scanning electron microscopic images. The average size of these hexagonal plates is ∼4 μm side and ∼30 nm of thickness. While on the glass substrate, a oriented hexagonal patterned ZnO nanorods (height ∼5 μm and 1 μm diameter) are observed and each rod is further decorated throughout the top few nanometers with several nanosteps. At the top of the nanorod, a perfectly hexagonal patterned ZnO surface with ∼250 nm sides is observed. The tendency to form hexagonal morphological features is due to the hexagonal crystal structure of ZnO confirmed from X-ray diffraction patterns and transmission electron microscopy image. The ZnAl: LDHs and/or ZnO coated substrates have been passivated by using stearic acid (SA) molecules. Infrared spectra of passivated ZnAl: LDHs coated substrates confirm the presence of SA. X-ray diffraction pattern also corroborates the results of infrared spectrum. The contact angle of the as prepared samples is zero. The superhydrophobicity is achieved by observing contact angle of ∼161° with a hysteresis of ∼4° for Al-substrate. On the glass substrate, a higher contact angle of ∼168° with a lower hysteresis of ∼3° is observed. A lower surface roughness of ∼4.93 μm is measured on ZnAl: LDHs surface layer on the Al substrate as compare to a higher surface roughness of 6.87 μm measured on ZnO layer on glass substrate. The superhydrophobicity of passivated nanostructured films on two different substrates is observed due to high surface roughness and low surface energy. - Highlights: • ZnAl: layered double hydroxides (LDHs) nanoplates are fabricated on Al substrate. • ZnO nanorods are fabricated on

  6. Formation of Nb3Al in powder processed Nb-Al superconductors

    International Nuclear Information System (INIS)

    Johnson, P.E.

    1987-05-01

    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 Nb 3 Al. 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 C 2 /) 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 C 2 /) be low. Thus the extent of the A15 (Nb 3 Al) reaction and the quality of the A15 formed are interdependent. This work focuses on the factors that control the extent of Nb 3 Al 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 Nb 3 Al 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

  7. Al-Si/B{sub 4}C composite coatings on Al-Si substrate by plasma spray technique

    Energy Technology Data Exchange (ETDEWEB)

    Sarikaya, Ozkan [Sakarya University, Faculty of Engineering, Department of Mechanical Engineering, Esentepe Campus, Sakarya 54187 (Turkey); Anik, Selahaddin [Sakarya University, Faculty of Engineering, Department of Mechanical Engineering, Esentepe Campus, Sakarya 54187 (Turkey); Aslanlar, Salim [Sakarya University, Faculty of Technical Education, Department of Mechanical Engineering, Esentepe Campus, Sakarya 54187 (Turkey); Cem Okumus, S. [Sakarya University, Faculty of Engineering, Department of Metallurgical and Materials Engineering, Esentepe Campus, Sakarya 54187 (Turkey); Celik, Erdal [Dokuz Eylul University, Engineering Faculty, Department of Metallurgical and Materials Engineering, Buca, Izmir 35160 (Turkey)]. E-mail: erdal.celik@deu.edu.tr

    2007-07-01

    Plasma-sprayed coatings of Al-Si/B{sub 4}C have been prepared on Al-Si piston alloys for diesel engine motors. The Al-Si/B{sub 4}C composite powders including 5-25 wt% B{sub 4}C were prepared by mixing and ball-milling processes. These powders were deposited on Al-Si substrate using an atmospheric plasma spray technique. The coatings have been characterised with respect to phase composition, microstructure, microhardness, bond strength and thermal expansion. It was found that Al, Si, B{sub 4}C and Al{sub 2}O{sub 3} phases were determined in the coatings with approximately 600 {mu}m thick by using X-ray diffraction analysis. Scanning electron microscope observation revealed that boron carbide particles were uniformly distributed in composite coatings and B{sub 4}C particles were fully wetted by Al-Si alloy. Also, no reaction products were observed in Al-Si/B{sub 4}C composite coatings. It was found that surface roughness, porosity, bond strength and thermal expansion coefficient of composite coatings decreased with increasing fraction of the boron carbide particle. It was demonstrated that the higher the B{sub 4}C content, the higher the hardness of coatings because the hardness of B{sub 4}C is higher than that of Al-Si.

  8. Fluctuations of charge variance and interaction time for dissipative processes in 27 Al + 27 Al collision

    International Nuclear Information System (INIS)

    Berceanu, I.; Andronic, A.; Duma, M.

    1999-01-01

    The systematic studies of dissipative processes in light systems were completed with experiments dedicated to the measurement of the excitation functions in 19 F + 27 Al and 27 Al + 27 Al systems in order to obtain deeper insight on DNS configuration and its time evolution. The excitation function for 19 F + 27 Al system evidenced fluctuations larger than the statistical errors. Large Z and angular cross correlation coefficients supported their non-statistical nature. The energy dependence of second order observables, namely the second moment of the charge distribution and the product ω·τ (ω - the angular velocity of the DNS and τ its mean lifetime) extracted from the angular distributions were studied for 19 F + 27 Al case. In this contribution we are reporting the preliminary results of similar studies performed for 27 Al + 27 Al case. The variance of the charge distribution were obtained fitting the experimental charge distribution with a Gaussian centered on Z = 13 and the product ω·τ was extracted from the angular distributions. The results for 19 F + 27 Al case are confirmed by a preliminary analysis of the data for 27 Al + 27 Al system. The charge variance and ω·τ excitation functions for Z = 11 fragment are represented together with the excitation function of the cross section. One has to mention that the data for 27 Al + 27 Al system were not corrected for particle evaporation processes. The effect of the evaporation corrections on the excitation function was studied using a Monte Carlo simulation. The α particle evaporation was also included and the evaluation of the particle separation energies was made using experimental masses of the fragments. The excitation functions for 27 Al + 27 Al system for primary and secondary fragments were simulated. No structure due to particle evaporation was observed. The correlated fluctuations in σ Z and ω·τ excitation functions support a stochastic exchange of nucleons as the main mechanism for

  9. Unprecedented Al supersaturation in single-phase rock salt structure VAlN films by Al+ subplantation

    Science.gov (United States)

    Greczynski, G.; Mráz, S.; Hans, M.; Primetzhofer, D.; Lu, J.; Hultman, L.; Schneider, J. M.

    2017-05-01

    Modern applications of refractory ceramic thin films, predominantly as wear-protective coatings on cutting tools and on components utilized in automotive engines, require a combination of excellent mechanical properties, thermal stability, and oxidation resistance. Conventional design approaches for transition metal nitride coatings with improved thermal and chemical stability are based on alloying with Al. It is well known that the solubility of Al in NaCl-structure transition metal nitrides is limited. Hence, the great challenge is to increase the Al concentration substantially while avoiding precipitation of the thermodynamically favored wurtzite-AlN phase, which is detrimental to mechanical properties. Here, we use VAlN as a model system to illustrate a new concept for the synthesis of metastable single-phase NaCl-structure thin films with the Al content far beyond solubility limits obtained with conventional plasma processes. This supersaturation is achieved by separating the film-forming species in time and energy domains through synchronization of the 70-μs-long pulsed substrate bias with intense periodic fluxes of energetic Al+ metal ions during reactive hybrid high power impulse magnetron sputtering of the Al target and direct current magnetron sputtering of the V target in the Ar/N2 gas mixture. Hereby, Al is subplanted into the cubic VN grains formed by the continuous flux of low-energy V neutrals. We show that Al subplantation enables an unprecedented 42% increase in metastable Al solubility limit in V1-xAlxN, from x = 0.52 obtained with the conventional method to 0.75. The elastic modulus is 325 ± 5 GPa, in excellent agreement with density functional theory calculations, and approximately 50% higher than for corresponding films grown by dc magnetron sputtering. The extension of the presented strategy to other Al-ion-assisted vapor deposition methods or materials systems is straightforward, which opens up the way for producing supersaturated single

  10. Erudición y nostalgia. Al-Hanīn ilà l-awtān en el editor de al-Faraŷ ba,d al-šidda de al-Tanūjī

    Directory of Open Access Journals (Sweden)

    Garulo, Teresa

    2012-06-01

    Full Text Available If you want to read a book, a medieval Arabic book, that talks to you about man and his relation with power (God’s power or any kind of worldly power, or about daily life in 10th century Basra or Baghdad, you will probably choose al-Tanūkhī’s works. His Nishwār al-muhādara wa-l-mudhākara or al-Faraj ba,d al-shidda are so widely and so well provided with stories, anecdotes, historical narratives, etc., that you won’t be able to drop it and probably will forget to read the many comments and marginal notes by, Abbūd al-Shāljī, its editor. But if you are wise enough, you will read everything he writes, because you will find in his remarks not only a sustained scholarliness but a fascinating evocation of his life in Irak, mostly in the thirties, with its cooking, manners and customs, and a pang of nostalgia that deserves, I think, at least a note or a friendly comment. In this paper I try to analyse some of his nostalgic memories of Baghdad and its people and places.Uno de los temas clásicos de la literatura árabe, casi desde sus comienzos, es la nostalgia de la tierra natal (al-hanīn ilà l-awtān. Experiencia dolorosa de extrañamiento, que se nutre de las crisis políticas, la nostalgia ha dado lugar a obras que buscan recrear un pasado o unos lugares amados, que sólo la memoria es capaz de recuperar. En este artículo trato de mostrar cómo se articula la nostalgia de Iraq, y, más concretamente, de Bagdad, dentro del aparato crítico de al-Faraŷ ba,da l-šidda de al-Tanūjī (329-384/941-994 (con el apoyo de Nišwār al-muhādara, también de dicho autor en la edición de, Abbūd al-Šālŷī, publicada en los años setenta. La representación que hace al-Tanūjī de la vida cotidiana de la capital abbasí, expresada a través de un lenguaje claro y natural, en el que tienen cabida expresiones populares, suscita en al-Šālŷī toda una serie de remembranzas, sobre todo de sus años juveniles, que se desbordan en sus notas, e

  11. Lou Gehrig's Disease (ALS)

    Science.gov (United States)

    ... disease. Who Gets ALS? Although this disease can strike anyone, ALS is extremely rare in kids. According ... home to provide care that the family cannot handle alone. Living With Lou Gehrig's Disease Living with ...

  12. Difficulties on study of ISM 26Al and a possible new way to nucleosynthesize 26Al-SNIa

    International Nuclear Information System (INIS)

    Peng Qiuhe

    1995-01-01

    Some observational results of the 1.809 MeV gamma-ray emitted by decay of the interstellar medium (ISM) 26 Al, which are obtained by spacecraft during (1979-1992) are firstly introduced. Secondly, both Mg-Al chain and Ne-Na cycle of nuclear reactions are discussed. Thirdly, some new experiments of nuclear physics, which are related with the question of the ISM 26 Al(e.g. measurements of the cross section of the nuclear reactions in the MgAl chain and in the NeNa cycle) are introduced. Then, comparing some experiments of nuclear physics, some difficulties confronted on various models responsible for the ISM 26 Al are discussed. The conclusions are: 1) all of hydrostatic H-burning models and all current nova models are hard to provide enough ISM 26 Al to be detected; 2) SN II + SN I b models are promising on responsibility for the half of ISM 26 Al, although current SN II + SN I b models should be improved, besides. Proposal of a new way to nucleosynthesizse 26 Al, 14 N + 16 O→ 26 Al + α, is suggested. SNI a as a possible source of the ISM 26 Al is discussed (63 refs.)

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

    International Nuclear Information System (INIS)

    Godefroid, L.B.

    1983-01-01

    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.) [pt

  14. AlGaN-Based Deep-Ultraviolet Light Emitting Diodes Fabricated on AlN/sapphire Template

    International Nuclear Information System (INIS)

    Li-Wen, Sang; Zhi-Xin, Qin; Hao, Fang; Yan-Zhao, Zhang; Tao, Li; Zheng-Yu, Xu; Zhi-Jian, Yang; Bo, Shen; Guo-Yi, Zhang; Shu-Ping, Li; Wei-Huang, Yang; Hang-Yang, Chen; Da-Yi, Liu; Jun-Yong, Kang

    2009-01-01

    We report on the growth and fabrication of deep ultraviolet (DUV) light emitting diodes (LEDs) on an AlN template which was grown on a pulsed atomic-layer epitaxial buffer layer. Threading dislocation densities in the AlN layer are greatly decreased with the introduction of this buffer layer. The crystalline quality of the AlGaN epilayer is further improved by using a low-temperature GaN interlayer between AlGaN and AlN. Electroluminescences of different DUV-LED devices at a wavelength of between 262 and 317 nm are demonstrated. To improve the hole concentration of p-type AlGaN, Mg-doping with trimethylindium assistance approach is performed. It is found that the serial resistance of DUV-LED decreases and the performance of DUV-LED such as EL properties is improved. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  15. Surface study and thickness control of thin Al2O3 film on Cu-9%Al(111) single crystal

    International Nuclear Information System (INIS)

    Yamauchi, Yasuhiro; Yoshitake, Michiko; Song Weijie

    2004-01-01

    We were successful in growing a uniform flat Al 2 O 3 film on the Cu-9%Al(111) surface using the improved cleaning process, low ion energy and short time sputtering. The growth of ultra-thin film of Al 2 O 3 on Cu-9%Al was investigated using Auger electron spectroscopy (AES) and a scanning electron microscope (SEM). The Al 2 O 3 film whose maximum thickness was about 4.0 nm grew uniformly on the Cu-9%Al surface. The Al and O KLL Auger peaks of Al 2 O 3 film shifted toward low kinetic energy, and the shifts were related to Schottky barrier formation and band bending at the Al 2 O 3 /Cu-9%Al interface. The thickness of Al 2 O 3 film on the Cu-9%Al surface was controlled by the oxygen exposure

  16. Microstructural and mechanical properties of Al-Mg/Al{sub 2}O{sub 3} nanocomposite prepared by mechanical alloying

    Energy Technology Data Exchange (ETDEWEB)

    Safari, J., E-mail: safari.jam@gmail.com [Department of Material Science and Engineering, Shahid Bahonar University of Kerman, P.O. Box No. 76135-133, Kerman (Iran, Islamic Republic of); Akbari, G.H. [Department of Material Science and Engineering, Shahid Bahonar University of Kerman, P.O. Box No. 76135-133, Kerman (Iran, Islamic Republic of); Research Center for Mineral Industries, Shahid Bahonar University of Kerman, P.O. Box No. 76135-133, Kerman (Iran, Islamic Republic of); Shahbazkhan, A. [Islamic Azad University, Saveh Branch, Saveh (Iran, Islamic Republic of); Delshad Chermahini, M. [Materials and Energy Research Center, Karaj (Iran, Islamic Republic of)

    2011-09-29

    Highlights: > The presence of Mg has remarkable effects on crystallite size and lattice strain. > The solution of Mg in the Al matrix accelerates the mechanical milling stages. > The microhardness increased in the presence of Mg. > The presence of Mg has significant effect on lattice parameter. > Steady-state situation was occurred in presence of Mg. - Abstract: The effect of milling time on the microstructure and mechanical properties of Al and Al-10 wt.% Mg matrix nanocomposites reinforced with 5 wt.% Al{sub 2}O{sub 3} during mechanical alloying was investigated. Steady-state situation was occurred in Al-10Mg/5Al{sub 2}O{sub 3} nanocomposite after 20 h, due to solution of Mg into Al matrix, while the situation was not observed in Al/5Al{sub 2}O{sub 3} nanocomposite at the same time. For the binary Al-Mg matrix, after 10 h, the predominant phase was an Al-Mg solid solution with an average crystallite size 34 nm. Up to 10 h, the lattice strain increased to about 0.4 and 0.66% for Al and Al-Mg matrix, respectively. The increasing of lattice parameter due to dissolution of Mg atom into Al lattice during milling was significant. By milling for 10 h the dramatic increase in microhardness (155 HV) for Al-Mg matrix nanocomposite was caused by grain refinement and solid solution formation. From 10 to 20 h, slower rate of increasing in microhardness may be attributed to the completion of alloying process, and dynamic and static recovery of powders.

  17. Different magnetic behaviour of the Kondo compounds Al3Ce and Al11Ce3

    International Nuclear Information System (INIS)

    Benoit, A.; Flouquet, J.; Palleau, J.; Buevoz, J.L.

    1979-08-01

    Neutron diffraction experiments on the Al 3 Ce and Al 11 Ce 3 compounds have been performed on the multidetector of the I.L.L. high flux reactor. No magnetic structure has been detected on the Al 3 Ce compound down to 20 mK. This confirms the non magnetic ground state of Al 3 Ce. For Al 11 Ce 3 , two magnetic structures have been observed: a ferromagnetic one at 4.2 K and an antiferromagnetic one at 2 K. The antiferromagnetic structure, which corresponds to a propagation vector (0,0,1/3), implies a strong reduction of the magnetic moment of determined sites; this reflects the Kondo character of the compounds

  18. Cast AlSi9Cu4 alloy with hybride strenghtened by Fe{sub x}Al{sub y}-Al{sub 2}O{sub 3} composite powder

    Energy Technology Data Exchange (ETDEWEB)

    Piatkowski, J [Department of Materials Technology, Silesian University of Technology, Krasinskiego 8, 40-019 Katowice (Poland); Formanek, B, E-mail: jaroslaw.piatkowski@polsl.pl, E-mail: boleslaw.formanek@polsl.pl [Department of Materials Science, Silesian University of Technology, Krasinskiego 8, 40-019 Katowice (Poland)

    2011-05-15

    The main objective of the study was to develop a technology of dispersion strenghtened hypoeutectic Al-Si alloy. The article presented the materials and technology conception for producing aluminium matrix composite AlSi9Cu4Fe alloy with hybride reinforcement of Al{sub x}Fe{sub y} intermetallic and aluminium oxide powders. Composite powder obtained in mechanical agllomerisation mixture of elemental powders. Changes in the structure were confirmed by TA and ATD thermal analyses plotting the solidification curves, which showed a decrease in temperature T{sub liq} compared to the unmodified alloy and an exothermic effect originating from the crystallisation of eutectics with alloying elements. The examinations carried out by SEM and BSE as well as the determination of local chemical composition by EDX technique have characterised the structure of the alloy as containing some binary Al-Si-Al-Cu and Al-Fe eutectics and multicomponent eutectics.

  19. Optical microcavities and enhanced electroluminescence from electroformed Al-Al{sub 2}O{sub 3}-Ag diodes

    Energy Technology Data Exchange (ETDEWEB)

    Hickmott, T. W. [Department of Physics, State University of New York at Albany, Albany, New York 12222 (United States)

    2013-12-21

    Electroluminescence (EL) and electron emission into vacuum (EM) occur when a non-destructive dielectric breakdown of Al-Al{sub 2}O{sub 3}-Ag diodes, electroforming, results in the development of a filamentary region in which current-voltage (I-V) characteristics exhibit voltage-controlled negative resistance. The temperature dependence of I-V curves, EM, and, particularly, EL of Al-Al{sub 2}O{sub 3}-Ag diodes with anodic Al{sub 2}O{sub 3} thicknesses between 12 nm and 30 nm, has been studied. Two filters, a long-pass (LP) filter with transmission of photons with energies less than 3.0 eV and a short-pass (SP) filter with photon transmission between 3.0 and 4.0 eV, have been used to characterize EL. The voltage threshold for EL with the LP filter, V{sub LP}, is ∼1.5 V. V{sub LP} is nearly independent of Al{sub 2}O{sub 3} thickness and of temperature and is 0.3–0.6 V less than the threshold voltage for EL for the SP filter, V{sub SP}. EL intensity is primarily between 1.8 and 3.0 eV when the bias voltage, V{sub S} ≲ 7 V. EL in the thinnest diodes is enhanced compared to EL in thicker diodes. For increasing V{sub S}, for diodes with the smallest Al{sub 2}O{sub 3} thicknesses, there is a maximum EL intensity, L{sub MX}, at a voltage, V{sub LMX}, followed by a decrease to a plateau. L{sub MX} and EL intensity at 4.0 V in the plateau region depend exponentially on Al{sub 2}O{sub 3} thickness. The ratio of L{sub MX} at 295 K for a diode with 12 nm of Al{sub 2}O{sub 3} to L{sub MX} for a diode with 25 nm of Al{sub 2}O{sub 3} is ∼140. The ratio of EL intensity with the LP filter to EL intensity with the SP filter, LP/SP, varies between ∼3 and ∼35; it depends on Al{sub 2}O{sub 3} thickness and V{sub S}. Enhanced EL is attributed to the increase of the spontaneous emission rate of a dipole in a non-resonant optical microcavity. EL photons interact with the Ag and Al films to create surface plasmon polaritons (SPPs) at the metal-Al{sub 2}O

  20. Microstructure and Properties of Fe3Al-Fe3AlC x Composite Prepared by Reactive Liquid Processing

    Science.gov (United States)

    Verona, Maria Nalu; Setti, Dalmarino; Paredes, Ramón Sigifredo Cortés

    2018-04-01

    A Fe3Al-Fe3AlC x composite was prepared using reactive liquid processing (RLP) through controlled mixture of carbon steel and aluminum in the liquid state. The microstructure and phases of the composite were assessed using X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, optical microscopy, and differential scanning calorimetry. In addition, the density, hardness, microhardness, and elastic modulus were evaluated. The Fe3Al-Fe3AlC x composite consisted of 65 vol pct Fe3Al and 35 vol pct Fe3AlC x ( κ). The κ phase contained 10.62 at. pct C, resulting in the stoichiometry Fe3AlC0.475. The elastic modulus of the Fe3Al-Fe3AlC0.475 composite followed the rule of mixtures. The RLP technique was shown to be capable of producing Fe3Al-Fe3AlC0.475 with a microstructure and properties similar to those achieved using other processing techniques reported in the literature.

  1. Appiah-Adjei et al

    African Journals Online (AJOL)

    PUBLICATIONS1

    ing, sale of automobile spare parts, and metal fabrication. Some of these activities generate huge ... Keywords: Groundwater quality, pollution, waste disposal, Suame, Ghana ... of fertilizers (Chen et al., 2007; Parris, 2011;. Shen et al., 2011), ...

  2. KONSEP MᾹQᾹṢID AL-SYᾹRĪAH MENURUT ṬᾹHᾹ JᾹBIR AL-‘ALWᾹNĪ

    Directory of Open Access Journals (Sweden)

    Chasnak Najidah

    2017-03-01

    Full Text Available One discourse which is receiving considerable attention from scholars of Islam is about the objectives of Islamic law (maqasid al-shari'ah. Taha Jabir al-'Alwānī as one reviewer of Maqasid al-shari'ah contemporary formulate the concept of maqasid al-shari'ah different from previous scholars. This article describes the concept of maqasid al-shari'ah by Taha Jabir al-'Alwānī. According to him, there are three levels of hierarchical of Maqasid al-Sharia. The highest value of maqasid al-shari'ah says is what he describes as al-Maqasid al-'ulyā al-Hakimah (intentions of the highest shari'ah and a legal basis, which consists of three main elements, namely al-Tawhid ( Onesess of God, al-Tazkiyah (purification and al-'umrān (prosperity. The position of the second al-shari'ah Maqasid are universal values such as justice, freedom, and equality. While the third position is the formulation of the previous scholars regarding maqasid al-shari'ah consisting of ḍarūriyyat, ḥājiyyāt, and taḥsīniyyāt. In terms of methodological, Taha Jabir al-'Alwānī basing the new system for Maqasid al-syarī'ahnya on the methods of al-jam'u Baina al-qirā'atain, a reading of the two entities: the revelation of God and the universe. With this basis, he argues that the maqasid al-shari'ah formulations are qaṭ'ī, so it can be a reference to the scholars in solving the problems of contemporary law.   [Salah satu diskursus yang mendapat perhatian cukup besar dari para akademisi Islam adalah seputar tujuan-tujuan hukum islam  (maqāṣid al-syarī'ah. Ṭāhā Jābir al-‘Alwānī sebagai salah satu ulama pengkaji maqāṣid asy-syarī’ahkontemporer merumuskan konsep maqāṣid asy-syarī’ahyang berbeda dari ulama sebelumnya. Artikel ini mendeskripsikan konsep maqāṣid asy-syarī’ahmenurut Ṭāhā Jābir al-‘Alwānī. Menurutnya, ada tiga tingkatan hierarkis maqāṣid al-syarī'ah. Nilai tertinggi maqāṣid asy-syarī’ahmenurutnya adalah apa

  3. Measurement of the d({sup 26}Al{sup m},p){sup 27}Al reaction for nuclear astrophysics

    Energy Technology Data Exchange (ETDEWEB)

    Roeder, B.T.; Trache, L.; Iacob, V.E.; McCleskey, M.; Simmons, E.; Spiridon, A.; Tribble, R.E. [Texas A and M Univ., TX (United States); Davinson, T.; Lotay, G.; Woods, P.J. [University of Edinburgh (United Kingdom); La Cognata, M.; Pizzone, R.G.; Rapisarda, G.G.; Sparta, R.; Spitaleri, C. [Istituto Nazionale di Fisica Nucleare (LNS/INFN), Catania (Italy). Lab. Nazionali del Sud

    2012-07-01

    Full text: The detection of gamma rays from the decay of the {sup 26}Al ground state in the galaxy gives evidence that nucleosynthesis is occurring in present-day stars, but its origin is not yet clear. This implies that reactions involving {sup 26}Al are important for astrophysical processes. In a recent experiment at the Cyclotron Institute at Texas A and M University, reactions with the ground state and isomeric state of {sup 26}Al were investigated with the Texas A and M-Edinburgh-Catania Silicon detector Array (TECSA). TECSA is a collaborative effort to build a high-efficiency detector Si array useful for measuring reactions of interest for nuclear astrophysics and nuclear structure. The array consists of up to 16 Micron Semiconductor YY1 detectors that are each 300 μm thick. Each detector has 16 annular ring sectors to measure the energy and the scattering angle of the detected particles. Using TECSA, we measured d({sup 26}Al{sup g},p){sup 27}Al and d({sup 26}Al{sup m},p){sup 27}Al with a {sup 26}Al secondary beam prepared in-flight with the MARS spectrometer. First, the composition of the {sup 26}Al beam was determined by measuring the ratio of beta-decays to {sup 26}Al ions produced. It was found that at different spectrometer rigidities, beams of 2/3 isomer to ground state ratio or vice-versa could be obtained. Then, in the second part of the experiment, angular distributions were measured for both reactions at backward angles with TECSA. The protons were measured in TECSA in coincidence with timing signals from the beam detected by a scintillator and with the cyclotron radio-frequency. Details of the experiment and preliminary results from the analysis of the d({sup 26}Al{sup m},p){sup 27}Al and d({sup 26}Al{sup g},p){sup 27}Al data will be presented. They will give information about the proton capture reactions {sup 26}Al{sup m}(p,γ){sup 27}Si and {sup 26}Al{sup g}(p,γ){sup 27}Si taking place in stars. (author)

  4. Khajeh Nasir al-Din al-Tusi’s Role in the Interaction of Triple Paradigms of Islamic Philosophy

    Directory of Open Access Journals (Sweden)

    r Mohammadzadeh

    2013-09-01

    Full Text Available Our aim in this article is to investigate Khajeh Nasir`s effective role in emergence, growth and development of triple paradigms of Islamic philosophy, that are, Masha’, Ishraq and al-Hekmah al-Motealiyeh. Thus, first we present a summary of the meaning of “paradigm” and then discuss Tusi`s role in the development of triple paradigms of Islamic philosophy. We believe that, by using an interactive approach, Khajeh Nasir has attained a new approach to understand the paradigms. He is the first thinker in Islamic world who created a constructive and effective interaction between two paradigms of Masha’ and Ishraq, and paved the way for the emergence of al-Hekmah al-Motealiyeh. This can be explained with regard to either the conceptualization of al-Hekmat al-Motealiyeh or epistemological approach. Al-Hekmah Al-Motealiyah was influenced a lot by Tusi.

  5. Characterization of microstructure and mechanical properties of friction stir welded AlMg5- Al_2O_3 nanocomposites

    International Nuclear Information System (INIS)

    Babu, N. Kishore; Kallip, Kaspar; Leparoux, Marc; AlOgab, Khaled A.; Reddy, G.M.; Talari, M.K.

    2016-01-01

    In the present study, powder metallurgy processed unmilled AlMg5, milled AlMg5 and milled AlMg5-0.5 vol% Al_2O_3 nanocomposite have been successfully friction stir welded (FSW). The effect of friction stir welding on the evolution of weld microstructures; hardness and tensile properties were studied and discussed in detail. FSW of unmilled AlMg5 resulted in significant grain refinement and strain hardening in the nugget zone induced by the thermo-mechanical processing, thereby increasing the stir zone hardness and tensile strengths to 100 HV and 324 MPa when compared to 80 HV and 300 MPa of base metal, respectively. In contrast, the FSW of milled AlMg5 and milled AlMg5-0.5 vol% Al_2O_3 samples showed a reduction in UTS values to 375 MPa and 401 MPa in the stir zone compared to 401 MPa and 483 MPa of respective base metal values. Transmission electron microscopic (TEM) investigation of weld stir zones revealed the homogenous distribution of Al_4C_3 nanophases in milled AlMg5 and Al_2O_3 nanoparticles in milled AlMg5-0.5 vol% Al_2O_3 samples throughout the aluminium matrix. It was revealed that the pre-stored energy from the prior ball milling and hot pressing processes, higher deformation energy and grain boundary pinning effect due to the presence of reinforcement particles has resulted in a higher recrystallization tendency and retarded grain growth during FSW of milled samples. The welds prepared with milled AlMg5-0.5 vol% Al_2O_3 exhibited higher hardness and tensile strength in the stir zone when compared to all other conditions which was attributed to Hall Petch effect due to fine grain size and Orowan strengthening effect due to Al_2O_3 reinforcements.

  6. Experimental investigation of the Al-Y phase diagram

    International Nuclear Information System (INIS)

    Liu Shuhong; Du Yong; Xu Honghui; He Cuiyun; Schuster, Julius C.

    2006-01-01

    The Al-Y phase diagram has been reinvestigated with 16 key alloys over its whole composition range by means of differential thermal analysis, X-ray diffraction, optical microscopy, and scanning electron microscopy with energy dispersive X-ray techniques. The existence of five intermetallic phases, Al 3 Y, Al 2 Y, AlY, Al 2 Y 3 , and AlY 2 , has been confirmed. Al 2 Y and Al 2 Y 3 melt congruently at 1490 ± 2 and 1105 ± 2 deg. C, respectively. Al 3 Y, AlY, and AlY 2 are formed via the peritectic reactions L + Al 2 Y ↔ Al 3 Y at 980 ± 2 deg. C, L + Al 2 Y ↔ AlY at 1138 ± 2 deg. C, and L + Al 2 Y 3 ↔ AlY 2 at 977 ± 2 deg. C, respectively. Three eutectic reactions L ↔ (Al) + Al 3 Y at 637 ± 2 deg. C, L ↔ AlY + Al 2 Y 3 at 1081 ± 2 deg. C, and L ↔ AlY 2 + (αY) at 955 ± 2 deg. C , are observed. The previously reported Al 3 Y 5 , AlY 3 compounds were not found. A revised Al-Y phase diagram is presented mainly based on the present experimental results

  7. The corrosion and mechanical behaviour of Al, FeCrAlY, and CoCrAlY coatings in aggressive environments

    NARCIS (Netherlands)

    Haanappel, V.A.C.; Haanappel, V.A.C.; Geerdink, Bert; Fransen, T.; Gellings, P.J.

    1991-01-01

    The mechanical and chemical behaviours of aluminide coatings applied by pack cementation, FeCrAlY coatings applied by plasma spraying and CoCrAlY coatings applied by electrodeposition were studied. The coatings were pretreated for 0.5 h in argon at 1373 K to improve the adhesion and structural

  8. Precipitation and strengthening phenomena in Al-Si-Ge and Al-Cu-Si-Ge alloys

    International Nuclear Information System (INIS)

    Mitlin, D.; Morris, J.W.; Dahmen, U.; Radmilovic, V.

    2000-01-01

    The objective of this work was to determine whether Al rich Al-Si-Ge and 2000 type Al-Cu-Si-Ge alloys have sufficient hardness to be useful for structural applications. It is shown that in Al-Si-Ge it is not possible to achieve satisfactory hardness through a conventional heat treatment. This result is explained in terms of sluggish precipitation of the diamond-cubic Si-Ge phase coupled with particle coarsening. However, Al-Cu-Si-Ge displayed a uniquely fast aging response, a high peak hardness and a good stability during prolonged aging. The high hardness of the Cu containing alloy is due to the dense and uniform distribution of fine θ' precipitates (metastable Al 2 Cu) which are heterogeneously nucleated on the Si-Ge particles. High resolution TEM demonstrated that in both alloys all the Si-Ge precipitates start out, and remain multiply twinned throughout the aging treatment. Since the twinned section of the precipitate does not maintain a low index interface with the matrix, the Si-Ge precipitates are equiaxed in morphology. Copyright (2000) AD-TECH - International Foundation for the Advancement of Technology Ltd

  9. Bankole et al (2)

    African Journals Online (AJOL)

    DELL

    Relationships of Clay-filled Channels on the Delta Flanks (Modified after Doust and Omatsola, 1990 and Lawrence et al., 2002). ... and in the Indo-Malaysian area (Germeraad et al.,. 1968). The genus ..... Upper Cretaceous of British Guiana.

  10. Aussprache als motorische Fertigkeit

    DEFF Research Database (Denmark)

    Bonner, Maria

    2013-01-01

    Authentische Aussprache gilt im Fremdsprachenunterricht als schwer erreichbares Ziel, fremdsprachlicher Akzent wird als nahezu unvermeidbar gesehen. Weder die Hypothese einer kritischen Periode für den Erwerb einer authentischen Aussprache noch das Konzept der Fossilierung im Sprachlernprozess...

  11. The removal of bisphenol A from aqueous solutions by MIL-53(Al) and mesostructured MIL-53(Al).

    Science.gov (United States)

    Zhou, Meimei; Wu, Yi-Nan; Qiao, Junlian; Zhang, Jing; McDonald, Amanda; Li, Guangtao; Li, Fengting

    2013-09-01

    In this work, metal-organic framework MIL-53(Al){Al(OH)[O2C-C6H4-CO2]} and MIL-53(Al)-F127{Al(OH)[O2C-C6H4-CO2]} were synthesized and used as sorbents to remove bisphenol A (BPA) from aqueous system. The sorption kinetics data of BPA were found to be in agreement with the pseudo-second-order model. The equilibrium sorption amounts of BPA on MIL-53(Al) and MIL-53(Al)-F127 reached 329.2±16.5 and 472.7±23.6 mg g(-1), respectively, far more than that of commercial activated carbons (ranging from 129.6 to 263.1 mg g(-1)). Both MIL-53(Al) and MIL-53(Al)-F127 could remove BPA fast from aqueous solutions, and the required contact time to reach equilibrium was approximately 90 min for MIL-53(Al) and 30 min for MIL-53(Al)-F127, respectively. The optimum pH levels for the removal of BPA using MIL-53 (Al) and MIL-53(Al)-F127 were 4 and 6 separately. The optimum temperature for the sorption behavior of BPA on the two sorbents was 20 °C. The results performed show that the resulting products, as one kind of MOFs, can be regarded as a new class of sorbents for water treatment and could find great applications in the fields of environmental water pollution control and resources reuse. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. Hyperfine fields and spin relaxation of Ce in GdAl2 and DyAl2

    International Nuclear Information System (INIS)

    Waeckelgaard, E.; Karlsson, E.; Lindgren, B.; Mayer, A.

    1987-04-01

    We have investigated the ferromagnetic state of the cubic intermetallic compounds GdAl 2 and DyAl 2 with the 140 Ce nuclei using DPAC. The local fields of Ce are for the lowest measured temperatures B eff (30 K) = 54(2) T for GdAl 2 and B eff (12.5 K) = 27(1) T for DyAl 2 which are considerably lower than the hyperfine field measured for a free Ce ion (183 T). By introducing a crystal field, of cubic symmetry, a lower hyperfine field is obtained which is in quantitative agreement with the local field of Ce in GdAl 2 . For DyAl 2 an additional effect, represented by a non-magnetic level below the lowest magnetic level, may explain a further reduction of the hyperfine field. Two models relating to a Kondo non-magnetic state of Ce are discussed. Spin relaxation in the paramagnetic state are also studied and compared with observations of the same systems measured with μSR. (authors)

  13. Experimental evidence of structural transition at the crystal-amorphous interphase boundary between Al and Al2O3

    International Nuclear Information System (INIS)

    Yang, Z.Q.; He, L.L.; Zhao, S.J.; Ye, H.Q.

    2002-01-01

    High-resolution transmission electron microscopy observations on the structure of the interphase boundary between crystalline Al and amorphous Al 2 O 3 coating reveal that an interfacial melting transition of Al occurs at 833 K, which is distinctly lower than the bulk melting point of Al. The crystalline lattice planes of Al near the interface bend or small segments of crystalline Al deviated from the matrix Al grains are formed. Stand-off dislocations formed at the interphase boundary are also observed. The amorphous Al 2 O 3 coating plays an important role in retaining the evidence for structural transition at high temperature to room temperature, which makes it possible to make experimental observations. (author)

  14. Room-Temperature Quantum Ballistic Transport in Monolithic Ultrascaled Al-Ge-Al Nanowire Heterostructures.

    Science.gov (United States)

    Sistani, Masiar; Staudinger, Philipp; Greil, Johannes; Holzbauer, Martin; Detz, Hermann; Bertagnolli, Emmerich; Lugstein, Alois

    2017-08-09

    Conductance quantization at room temperature is a key requirement for the utilizing of ballistic transport for, e.g., high-performance, low-power dissipating transistors operating at the upper limit of "on"-state conductance or multivalued logic gates. So far, studying conductance quantization has been restricted to high-mobility materials at ultralow temperatures and requires sophisticated nanostructure formation techniques and precise lithography for contact formation. Utilizing a thermally induced exchange reaction between single-crystalline Ge nanowires and Al pads, we achieved monolithic Al-Ge-Al NW heterostructures with ultrasmall Ge segments contacted by self-aligned quasi one-dimensional crystalline Al leads. By integration in electrostatically modulated back-gated field-effect transistors, we demonstrate the first experimental observation of room temperature quantum ballistic transport in Ge, favorable for integration in complementary metal-oxide-semiconductor platform technology.

  15. The effectiveness of ERC advanced life support (ALS) provider courses for the retention of ALS knowledge.

    Science.gov (United States)

    Fischer, Henrik; Strunk, Guido; Neuhold, Stephanie; Kiblböck, Daniel; Trimmel, Helmut; Baubin, Michael; Domanovits, Hans; Maurer, Claudia; Greif, Robert

    2012-02-01

    Out-of-hospital emergency physicians in Austria need mandatory emergency physician training, followed by biennial refresher courses. Currently, both standardized ERC advanced life support (ALS) provider courses and conventional refresher courses are offered. This study aimed to compare the retention of ALS-knowledge of out-of-hospital emergency physicians depending on whether they had or had not participated in an ERC-ALS provider course since 2005. Participants (n=807) from 19 refresher courses for out-of-hospital emergency physicians answered eight multiple-choice questions (MCQ) about ALS based on the 2005 ERC guidelines. The pass score was 75% correct answers. A multivariate logistic regression analyzed differences in passing scores between those who had previously participated in an ERC-ALS provider course and those who had not. Age, gender, regularity of working as an out-of-hospital emergency physician and the self-reported number of real resuscitation efforts within the last 6months were entered as control variables. Out-of-hospital emergency physicians who had previously attended an ERC-ALS provider course had a significantly higher chance of passing the MCQ test (OR=1.60, p=0.015). Younger age (OR=0.95, pERC-ALS provider course since 2005 had a higher retention of ALS knowledge compared to non-ERC-ALS course participants. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  16. X-ray study of rapidly cooled ribbons of Al-Cr-Zr and Al-Ni-Y-Cr-Zr alloys

    International Nuclear Information System (INIS)

    Betsofen, S.Ya.; Osintsev, O.E.; Lutsenko, A.N.; Konkevich, V.Yu.

    2002-01-01

    One investigated into phase composition, lattice spacing and structure of rapidly cooled 25-200 μm gauge strips made of Al-4,1Cr-3,2Zr and Al-1,5Cr-1,5Zr-4Ni-3Y alloys, wt. %, produced by melt spinning to a water-cooled copper disk. In Al-4,1Cr-3,2Zr alloy one detected intermetallic phases: Al 3 Zr and two Al 86 Cr 14 composition icosahedral phases apart from aluminium solid solution with 4.040-4.043 A lattice spacing. In Al-1,5Cr-1,5Zr-4Ni-3Y alloy one identified two Al 86 Cr 14 icosahedral phases and two AlNiY and Al 3 Y yttrium-containing ones, lattice spacing of aluminium solid solution was equal to 4.052-4.053 A [ru

  17. The Influence of the Asymmetric Arb Process on the Properties of Al-Mg-Al Multi-Layer Sheets / Wpływ Asymetrii W Procesie Arb Na Właściwości Wielowarstwowych Blach Al-Mg-Al

    Directory of Open Access Journals (Sweden)

    Wierzba A.

    2015-12-01

    Full Text Available The paper presents the results of the experimental study of the three-layer Al-Mg-Al sheets rolling process by the ARB method. The tests carried out were limited to single-pass symmetric and asymmetric rolling processes. An Al-Mg-Al package with an initial thickness of 4 mm (1-2-1 mm was subjected to the process of rolling with a relative reduction of 50%. To activate the shear band in the strip being deformed, an asymmetry factor of av=2 was applied. From the test results, an increase in the tensile strength of the multi-layer Al-Mg-Al sheets obtained from the asymmetric process was observed. Microhardness tests did not show any significant differences in aluminium layer between respective layers of sheets obtained from the symmetric and the asymmetric process. By contrast, for the magnesium layer, an increase in microhardness from 72 HV to 79 HV could be observed for the asymmetric rolling. The analysis of the produced Al-Mg-Al sheets shows that the good bond between individual layers and grain refinement in the magnesium layer contributed to the obtaining of higher mechanical properties in the multi-layer sheets produced in the asymmetric process compared to the sheets obtained from the symmetric process.

  18. The investigation of Al0.29Ga0.71N/GaN/AlN and AlN/GaN/AlN thin films grown on Si (111) by RF plasma-assisted MBE

    Science.gov (United States)

    Yusoff, Mohd Zaki Mohd; Mahyuddin, Azzafeerah; Hassan, Zainuriah; Hassan, Haslan Abu; Abdullah, Mat Johar

    2012-06-01

    Recently, gallium nitride (GaN) and its related compounds involving Al and In have attracted much attention because of their potential to be used as high-efficiency UV light emitting devices, and as high frequency and high power electronic devices. Consequently, the growth and physics of GaN-based materials have attracted remarkable scientific attention. In this work, the growth and characterization of epitaxial Al0.29Ga0.71N and AlN layers grown on Si (111) by RF-plasma assisted molecular beam epitaxy (MBE) are described. The Al mole fraction was derived from the HR-XRD symmetric rocking curve (RC) ω/2θ scans of (0002) plane as x = 0.29. For AlN/GaN/AlN sample, the maximum Raman intensity at 521.53 cm-1 is attributed to crystalline silicon. It was found that the allowed Raman optical phonon mode of GaN, the E1 (high) is clearly visible, which is located at 570.74 cm-1. Photoluminscence (PL) spectrums of both samples have shown sharp and intense band edge emission of GaN without the existence of yellow emission band, showing good crystal quality of the samples have been successfully grown on Si substrate.

  19. Field ion microscopy and 3-D atom probe analysis of Al3Zr particles in 7050 Al alloy

    International Nuclear Information System (INIS)

    Sha, G.; Cerezo, A.

    2004-01-01

    Full text: For high strength 7xxx series Al alloys, Zr is an important trace alloy element which is often added to optimise properties, having effects such as refining grain size, inhibiting recrystallization, and improving stress corrosion cracking resistance and quench sensitivity. In addition, it has been reported recently that Zr addition also has a significant influence on early stage ageing behaviour of a 7xxx series Al alloy. Zr equilibrium solubility in solid Al is extremely low. After solution or ageing treatment, most Zr is present as small spherical Ai 3 Zr dispersoids approximately 20 nm in diameter, distributed at grain boundaries as well as within the Al matrix. The crystallographic nature of intermetallic phase Al 3 Zr has been well studied in the literatures. So far, no direct measurement of the chemistry of the Al 3 Zr particles in 7xxx series Al alloys has been published. It is unclear if there is significant Zn, Mg or Cu included in the particles. In this research, 3DAP has been employed for the first time to investigate ionisation behaviour of Al 3 Zr particles and determine the chemistry of the particles in 7050 Al alloy. Using field ion microscopy, the local evaporation radius of the Al 3 Zr particle has been measured to be equivalent to 36 nm for a 10 kV tip, less than the equivalent tip radius for the Al matrix of ∼68 nm. Using the matrix Al evaporation field (19 V/nm) as a reference, this allows the evaporation field of Al 3 Zr to be calculated as 35 V/nm, the same as the field calculated for evaporation of Al as Al 2+ (35 V/nm), and that of Zr as Zr 3+ (35 V/nm). This result is consistent with Al 2+ and Zr 3+ being the main species observed in the mass spectrum during analysis of Al 3 Zr particles. Using 3DAP, the chemical compositions of Al 3 Zr particles are determined to be 64.8∼67.7 at% Al, 23.6∼24.8 at% Zr, 6.9∼9.1 at% Zn, 0.4∼0.7 at% Cu, 0.5∼1.2 at% Mg, with a (Al+Zn)/Zr ratio close to 3. Choice of specimen temperature of

  20. Synthesis and structural transformations of hydrotalcite-like materials Mg-Al and Zn-Al

    NARCIS (Netherlands)

    Prihod'ko, R.V.; Sychev, M.V.; Astrelin, I.M.; Erdmann, K.; Mangel, A.; Santen, van R.A.

    2001-01-01

    Mg-Al and Zn-Al hydrotalcite-like layered double hydroxides of various compositions were synthesized and characterized. A detailed comparative analysis of the structure and composition of starting and reconstructed layered double hydroxides was made

  1. Natural radioactivity survey in Al-Jabal Al-Gharbi Mountain Region Libya

    International Nuclear Information System (INIS)

    Askouri, N.A.; Hussain, M.O.; Al-Ojaily, A.S.

    2011-01-01

    The measurement of natural radioactivity in a given region or country is essential to provide a reference base-line map to follow up a possible variation in future. In order to perform such measurement, the natural radioactivity was measured in different locations. The locations (50 sites) were distributed over Al-Jabal Al-Gharbi Mountain, starting from the city Al-Azeeziah in the eastern part to Wazen on the Tunisian border in the west. The measurements showed obvious variation from one site to another. The levels were fluctuating from (12.8 counts/minute) in Bir-Ayad to (45.7 counts/minute) in Gherian. In order to investigate the cause for such variation, samples were collected from (27) sites for detailed study. The levels of natural radioactivity were determined in the laboratory, and were ranging from (58.7 Bq/kg) in Bir-Ayad to (102.1 Bq/kg) in Gherian. The variation in measured radioactivity was related to the geological structures taken in six perpendicular sections, namely, Gharian, Yevren, Zintan, Nalut, Wazen and Al-Azeeziah taking the naturally occurred radioisotopes concentration of 4 0K, 232 Th and 238 U present in consideration.

  2. Phase constituents and microstructure of laser cladding Al2O3/Ti3Al reinforced ceramic layer on titanium alloy

    International Nuclear Information System (INIS)

    Li Jianing; Chen Chuanzhong; Lin Zhaoqing; Squartini, Tiziano

    2011-01-01

    Research highlights: → In this study, Fe 3 Al has been chosen as cladding powder due to its excellent properties of wear resistance and high strength, etc. → Laser cladding of Fe 3 Al + TiB 2 /Al 2 O 3 pre-placed alloy powder on Ti-6Al-4V alloy substrate can form the Ti 3 Al/Fe 3 Al + TiB 2 /Al 2 O 3 ceramic layer, which can increase wear resistance of substrate. → In cladding process, Al 2 O 3 can react with TiB 2 leading to formation of Ti 3 Al and B. → This principle can be used to improve the Fe 3 Al + TiB 2 laser-cladded coating. - Abstract: Laser cladding of the Fe 3 Al + TiB 2 /Al 2 O 3 pre-placed alloy powder on Ti-6Al-4V alloy can form the Ti 3 Al/Fe 3 Al + TiB 2 /Al 2 O 3 ceramic layer, which can greatly increase wear resistance of titanium alloy. In this study, the Ti 3 Al/Fe 3 Al + TiB 2 /Al 2 O 3 ceramic layer has been researched by means of electron probe, X-ray diffraction, scanning electron microscope and micro-analyzer. In cladding process, Al 2 O 3 can react with TiB 2 leading to formation of amount of Ti 3 Al and B. This principle can be used to improve the Fe 3 Al + TiB 2 laser cladded coating, it was found that with addition of Al 2 O 3 , the microstructure performance and micro-hardness of the coating was obviously improved due to the action of the Al-Ti-B system and hard phases.

  3. Precipitation in cold-rolled Al-Sc-Zr and Al-Mn-Sc-Zr alloys prepared by powder metallurgy

    KAUST Repository

    Vlach, Martin

    2013-12-01

    The effects of cold-rolling on thermal, mechanical and electrical properties, microstructure and recrystallization behaviour of the AlScZr and AlMnScZr alloys prepared by powder metallurgy were studied. The powder was produced by atomising in argon with 1% oxygen and then consolidated by hot extrusion at 350 C. The electrical resistometry and microhardness together with differential scanning calorimetry measurements were compared with microstructure development observed by transmission and scanning electron microscopy, X-ray diffraction and electron backscatter diffraction. Fine (sub)grain structure developed and fine coherent Al3Sc and/or Al3(Sc,Zr) particles precipitated during extrusion at 350 C in the alloys studied. Additional precipitation of the Al3Sc and/or Al3(Sc,Zr) particles and/or their coarsening was slightly facilitated by the previous cold rolling. The presence of Sc,Zr-containing particles has a significant antirecrystallization effect that prevents recrystallization at temperatures minimally up to 420 C. The precipitation of the Al6Mn- and/or Al 6(Mn,Fe) particles of a size ~ 1.0 μm at subgrain boundaries has also an essential antirecrystallization effect and totally suppresses recrystallization during 32 h long annealing at 550 C. The texture development of the alloys seems to be affected by high solid solution strengthening by Mn. The precipitation of the Mn-containing alloy is highly enhanced by a cold rolling. The apparent activation energy of the Al3Sc particles formation and/or coarsening and that of the Al6Mn and/or Al 6(Mn,Fe) particle precipitation in the powder and in the compacted alloys were determined. The cold deformation has no effect on the apparent activation energy values of the Al3Sc-phase and the Al 6Mn-phase precipitation. © 2013 Elsevier Inc.

  4. Precipitation in cold-rolled Al-Sc-Zr and Al-Mn-Sc-Zr alloys prepared by powder metallurgy

    KAUST Repository

    Vlach, Martin; Stulí ková , Ivana; Smola, Bohumil; Kekule, Tomá š; Kudrnová , Hana; Daniš, Stanislav; Gemma, Ryota; Očená šek, Vladivoj; Má lek, Jaroslav; Tanprayoon, Dhritti; Neubert, Volkmar

    2013-01-01

    The effects of cold-rolling on thermal, mechanical and electrical properties, microstructure and recrystallization behaviour of the AlScZr and AlMnScZr alloys prepared by powder metallurgy were studied. The powder was produced by atomising in argon with 1% oxygen and then consolidated by hot extrusion at 350 C. The electrical resistometry and microhardness together with differential scanning calorimetry measurements were compared with microstructure development observed by transmission and scanning electron microscopy, X-ray diffraction and electron backscatter diffraction. Fine (sub)grain structure developed and fine coherent Al3Sc and/or Al3(Sc,Zr) particles precipitated during extrusion at 350 C in the alloys studied. Additional precipitation of the Al3Sc and/or Al3(Sc,Zr) particles and/or their coarsening was slightly facilitated by the previous cold rolling. The presence of Sc,Zr-containing particles has a significant antirecrystallization effect that prevents recrystallization at temperatures minimally up to 420 C. The precipitation of the Al6Mn- and/or Al 6(Mn,Fe) particles of a size ~ 1.0 μm at subgrain boundaries has also an essential antirecrystallization effect and totally suppresses recrystallization during 32 h long annealing at 550 C. The texture development of the alloys seems to be affected by high solid solution strengthening by Mn. The precipitation of the Mn-containing alloy is highly enhanced by a cold rolling. The apparent activation energy of the Al3Sc particles formation and/or coarsening and that of the Al6Mn and/or Al 6(Mn,Fe) particle precipitation in the powder and in the compacted alloys were determined. The cold deformation has no effect on the apparent activation energy values of the Al3Sc-phase and the Al 6Mn-phase precipitation. © 2013 Elsevier Inc.

  5. Universitat popular al Cabanyal

    OpenAIRE

    Ribés Granell, Juan Miguel

    2012-01-01

    La intención es dotar al barrio de un gran espacio verde y de un edificio de interés para los vecinos que enriquezca al Cabanyal, ya que actualmente se encuentra en proceso de degradación. Se pretende desarrollar un proyecto que signifique una mejora en la predisposición del visitante, cubriendo sus necesidades. Al mismo tiempo, se busca crear un espacio arquitectónico que mejore la relación entre las actividades que incluye y su entorno. El proyecto está condicionado por cuatro aspectos fund...

  6. Nonequilibrium synthesis of NbAl3 and Nb-Al-V alloys by laser cladding. II - Oxidation behavior

    Science.gov (United States)

    Haasch, R. T.; Tewari, S. K.; Sircar, S.; Loxton, C. M.; Mazumder, J.

    1992-01-01

    Isothermal oxidation behaviors of NbAl3 alloy synthesized by laser cladding were investigated at temperatures between 800 and 1400 C, and the effect of vanadium microalloying on the oxidation of the laser-clad alloy was examined. The oxidation kinetics of the two alloys were monitored using thermal gravimetric weight gain data, and the bulk and surface chemistries were analyzed using XRD and XPS, respectively. It was found that NbAl3 did not form an exclusive layer of protective Al2O3. The oxidation products at 800 C were found to be a mixture of Nb2O5 and Al2O3. At 1200 C, a mixture of NbAlO4, Nb2O5, and Al2O3 formed; and at 1400 C, a mixture of NbAlO4, Al2O3, NbO2, NbO(2.432), and Nb2O5 formed. The addition of V led to a dramatic increase of the oxidation rate, which may be related to the formation of (Nb, V)2O5 and VO2, which grows in preference to protective Al2O3.

  7. Completing the Heterocubane Family [Cp*AlE]4 (E = O, S, Se, and Te) by Selective Oxygenation and Sulfuration of [Cp*Al]4: Density Functional Theory Calculations of [Cp*AlE]4 and Reactivity of [Cp*AlO]4 toward Hydrolysis.

    Science.gov (United States)

    Stelzer, Adrian C; Hrobárik, Peter; Braun, Thomas; Kaupp, Martin; Braun-Cula, Beatrice

    2016-05-16

    The subvalent aluminum compound [Cp*Al]4 (1) reacts with dioxygen, N2O, or sulfur to yield the heterocubane complexes [Cp*AlX]4 [X = O (2) and S (3)]. Treatment of [Cp*AlO]4 (2) with (tBuO)3SiOH gave [(tBuO)3SiOAlO]4 (6) and Cp*H. The structures and spectroscopic data of the Al clusters are supported by density functional theory (DFT) calculations, which also demonstrate the importance of noncovalent interactions (NCI) in oligomeric Al(I) complexes as well as in [Cp*AlS]4 and the heavier homologues of Se and Te. The computed (27)Al NMR shifts indicate a deshielding at the Al centers with increasing electronegativity of the chalcogen atom as well as significant spin-orbit shielding effects within the heavier heterocubane [Al4E4] cores. Further hydrolysis of 6 with an additional amount of silanol in the presence of water resulted in the formation of [Al4(OH)6(OH2)2(OSiOtBu3)6] (7), which shows a structural motif found in boehmite and diaspore.

  8. Reciprocating Wear Behaviour of 7075Al/SiC and 6061Al/Al2O3 Composites: A study of Effect of Reinforcement, Stroke and Load

    Directory of Open Access Journals (Sweden)

    J. Lakshmipathy

    2014-06-01

    Full Text Available 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 tested samples are examined in Scanning Electron Microscope (SEM. Hardness test and impact test are also carried out on the MMC samples. The experimental results shows that hardness of composites increases with increase in SiC and Al2O3 particle and the impact strength decreases with increase in SiC and Al2O3 content. The volume loss of MMC specimens are less than that of the matrix alloy. The temperature rise near the contact surface of the MMC specimens increases with increase in wt% of SiC and Al2O3, load and number of strokes. The coefficient of friction decreases with increase in the number of strokes. The WVAS (Wireless Vibration Acquisition System interfaced with MAT Lab software is used to record the amplitudes during the test.

  9. Microstructure of two phases alloy Al3Ti/Al3Ti0.75Fe0.25

    International Nuclear Information System (INIS)

    Angeles, C.; Rosas, G.; Perez, R.

    1998-01-01

    The titanium-aluminium system presents three intermetallic compounds from those Al 3 Ti is what less attention has received. The objective of this work is to generate and characterize the microstructure of multiphase alloys nearby to Al 3 Ti compound through Fe addition as alloying. This is because it has been seen that little precipitates of Al 2 Ti phase over Al 3 Ti intermetallic compound increases its ductility. (Author)

  10. Microstructural characterisation of Ni75Al25 and Ni31.5Al68.5 powder particles produced by gas atomisation

    International Nuclear Information System (INIS)

    García-Escorial, A.; Lieblich, M.

    2014-01-01

    Highlight: ► Successful production of gas atomised Ni75Al25 and Ni31.5Al68.5 powder particles. ► Characterization of the as-solidified microstructure of 75 Al 25 and Ni 31.5 Al 68.5 at.% powder particles below 100 μm in size have been studied. The gas atomised Ni 75 Al 25 powder particles are mainly spherical. The solidification of this alloy is very fast, and its microstructure consists of a dendrite and lamellar structure of partially ordered γ-(Ni), γ′-Ni 3 Al L1 2 phase, and β-NiAl phase. The order increases with the powder particle size. The gas atomised Ni 31.5 Al 68.5 powder particles are also spherical in shape. The microstructure consists of Ni 2 Al 3 dendrites with interdendritic peritectic NiAl 3 and eutectic NiAl 3 + α-Al. The amount of the Ni 2 Al 3 increases as the cooling rate increases. NiAl phase is absent in the gas atomised Ni 31.5 Al 68.5 powder

  11. Explosive destruction of "2"6Al

    International Nuclear Information System (INIS)

    Kahl, D.; Yamaguchi, H.; Shimizu, H.

    2016-01-01

    The γ-ray emission associated with the radioactive decay of "2"6Al is one of the key pieces of observational evidence indicating stellar nucleosynthesis is an ongoing process in our Galaxy, and it was the first such radioactivity to be detected. Despite numerous efforts in stellar modeling, observation, nuclear theory, and nuclear experiment over the past four decades, the precise sites and origin of Galactic "2"6Al remain elusive. We explore the present experimental knowledge concerning the destruction of "2"6Al in massive stars. The precise stellar rates of neutron-induced reactions on "2"6Al, such as (n,p) and (n,α), have among the largest impacts on the total "2"6Al yield. Meanwhile, reactions involving the short-lived isomeric state of "2"6Al such as radiative proton capture are highly-uncertain at present. Although we presented on-going experimental work from n TOF at CERN with an "2"6Al target, the present proceeding focuses only on the "2"6Al isomeric radioactive beam production aspect and the first experimental results at CRIB.

  12. Al-Biruni: A Muslim Critical Thinker

    Directory of Open Access Journals (Sweden)

    Mohammad Noviani Ardi

    2016-03-01

    Full Text Available As an academic course, critical thinking has emerged in the last century as the one of the important subjects, especially in the second half. But as a kind of thinking and a process of the human reason, it was exist as old as mankind. What are known, nowadays, as (standards of critical thinking or (characteristic of critical thinker were used by some ancient Greek philosophers, e.g. Socrates, Aristotle, as well as great Muslim scholars, e.g. al-Biruni, al-Ghazali, etc. al-Biruni was known as a great Muslim scholar due to objectively scientific method in his works. Moreover, he also was famed in comparative religion which early in history of discipline of comparative religion. However, this study attempts to talk about al-Biruni, one of greatest Muslim scholar in history from another side of previously discussion. It is tries to analyze al-Biruni as a Muslim critical thinker based on his monumental work of Tahqiq ma li al-Hind min Maqulah Maqbulah fi al-‘Aql aw Mardhulah or it is known by Kitab al-Hind.

  13. A comparative wear study on Al-Li and Al-Li/SiC composite

    Energy Technology Data Exchange (ETDEWEB)

    Okumus, S. Cem, E-mail: cokumus@sakarya.edu.tr; Karslioglu, Ramazan, E-mail: cokumus@sakarya.edu.tr; Akbulut, Hatem, E-mail: cokumus@sakarya.edu.tr [Sakarya University Engineering Faculty, Department of Metallurgical and Materials Engineering, Esentepe Campus, 54187, Sakarya (Turkey)

    2013-12-16

    Aluminum-lithium based unreinforced (Al-8090) alloy and Al-8090/SiCp/17 vol.% metal matrix composite produced by extrusion after spray co-deposition. A dry ball-on disk wear test was carried out for both alloy and composite. The tests were performed against an Al{sub 2}O{sub 3} ball, 10 mm in diameter, at room temperature and in laboratory air conditions with a relative humidity of 40-60%. Sliding speed was chosen as 1.0 ms{sup −1} and normal loads of 1.0, 3.0 and 5.0 N were employed at a constant sliding distance of 1000 m. The wear damage on the specimens was evaluated via measurement of wear depth and diameter. Microstructural and wear characterization was carried out via scanning electron microscopy (SEM). The results showed that wear loss of the Al-8090/SiC composite was less than that of the Al-8090 matrix alloy. Plastic deformation observed on the wear surface of the composite and the matrix alloy, and the higher the applied load the greater the plastic deformation. Scanning electron microscopy examinations of wear tracks also reveal that delamination fracture was the dominant wear mechanism during the wear progression. Friction coefficient was maximum at the low applied load in the case of the Al-8090/SiC composite while a gradual increase was observed with applied load for the matrix alloy.

  14. 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.

  15. BERKELEY: ALS ring

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1993-06-15

    Everybody at Lawrence Berkeley Laboratory's Center for Beam Physics is pleased with the rapid progress in commissioning LBL's Advanced Light Source (ALS) electron storage ring, the foundation for this third-generation synchrotron radiation facility. Designed for a maximum current of 400 mA, the ALS storage ring reached 407 mA just 24 days after storing the first beam on 16 March. ALS construction as a US Department of Energy (DOE) national user facility to provide high-brightness vacuum ultra-violet and soft x-ray radiation began in October 1987. One technical requirement marking project completion was to accumulate a 50-mA current in the storage ring. The ALS passed this milestone on 24 March, a week ahead of the official deadline. Once injected, the electron beam decays quasi-exponentially primarily because of interactions with residual gas molecules in the storage-ring vacuum chamber. Eventually, when the pressure in the vacuum chamber with beam decreases toward the expected operating level of 1 nano Torr, it will only be necessary to refill the storage ring at intervals of four to eight hours. At present the vacuum is improving rapidly as surfaces are irradiated (scrubbed) by the synchrotron radiation itself. At 100 mA, beam lifetime was about one hour (9 April)

  16. BERKELEY: ALS ring

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    Everybody at Lawrence Berkeley Laboratory's Center for Beam Physics is pleased with the rapid progress in commissioning LBL's Advanced Light Source (ALS) electron storage ring, the foundation for this third-generation synchrotron radiation facility. Designed for a maximum current of 400 mA, the ALS storage ring reached 407 mA just 24 days after storing the first beam on 16 March. ALS construction as a US Department of Energy (DOE) national user facility to provide high-brightness vacuum ultra-violet and soft x-ray radiation began in October 1987. One technical requirement marking project completion was to accumulate a 50-mA current in the storage ring. The ALS passed this milestone on 24 March, a week ahead of the official deadline. Once injected, the electron beam decays quasi-exponentially primarily because of interactions with residual gas molecules in the storage-ring vacuum chamber. Eventually, when the pressure in the vacuum chamber with beam decreases toward the expected operating level of 1 nano Torr, it will only be necessary to refill the storage ring at intervals of four to eight hours. At present the vacuum is improving rapidly as surfaces are irradiated (scrubbed) by the synchrotron radiation itself. At 100 mA, beam lifetime was about one hour (9 April)

  17. Lukman et al. (5)

    African Journals Online (AJOL)

    DELL

    1 Civil Engineering Department, Obafemi Awolowo University, Ile-Ife- Nigeria and Corresponding author. 2Department of Water Resources and Environmental Engineering, Ahmadu Bello University, Samaru, Zaria- Nigeria s Department of Civil Engineering, University of Hafr Al-Batin, Hafr Al-Batin, Saudi Arabia.

  18. MEMBUKA TABIR SUMPAH DALAM AL-QUR’AN (Studi Analisis Penafsiran ‘A’isyah Bint Al-Syati’ Tentang Ayat-Ayat Sumpah

    Directory of Open Access Journals (Sweden)

    Muhammad Hasdin Has

    2016-01-01

    Full Text Available Abstract This study discusses al-Aqsam fi al-Qur'an (Interpretation of 'A'isyah bint al-Shati 'in Kitab al-Tafsir al-Baya ni li al -Qur'a al-Karim. This research conducted library research by using the hermeneutics, philology, sociology, historical, and psychological approach. Results of this study conclude that curse in Tafsir al-Bayani is composed two aspects, the etymology and terminology. In terms of etymology, curse is true meaning and earnest pronounced by the reciter. As for the aspects of terminology, curse is a verse by way of sensory reasoning. It is diverting attention (la fitah of something that can be felt (Hissi to something abstract. The forms of curse are two, the oath with the letter wau al-qasam and vows with the letter la. The function of curse in al-Tafsir al-Bayani has shifted from its original function of which is to exalt or glorify oath object into a rhetorical aged in which aims to analogize between muqsam bih with Javab al-qasam. Keyword: curse, Bint Syati, interpretation.   Abstrak Tulisan ini membahas topik al-Aqsam fi al-Qur’an (Studi Penafsiran ‘A’isyah bint al-Syati’ dalam Kitab al-Tafsir al-Bayani li al-Qur’an al-Karim tentang Ayat-ayat sumpah. Untuk menjawab permasalahan pokok di atas maka dilakukan penelitian kepustakaan (library research dengan menggunakan pendekatan ilmu tafsir, filologi, sosiologi, historis, dan psikologis. Hasil Penelitian ini menyimpulkan: 1 Hakikat qasam dalam al-Tafsir al-Bayani terdiri dari dua aspek, yaitu etimologi dan terminologi. Dari segi etimologi qasam bermakna sumpah yang benar berbeda dengan kata half yang mengandung arti kebohongan sumpah dan ketidaksungguhan si pengucapnya. Secara terminologi, qasam adalah gaya bahasa dalam al-Qur’an yang menjelaskan makna sebuah ayat dengan cara penalaran indrawi yaitu pengalihan perhatian (lafitah dari sesuatu yang dapat dirasakan (hissi kepada sesuatu yang abstrak. 2 Bentuknya ada dua, yaitu sumpah dengan huruf wau al-qasam dan

  19. Application of Al-2La-1B Grain Refiner to Al-10Si-0.3Mg Casting Alloy

    Science.gov (United States)

    Jing, Lijun; Pan, Ye; Lu, Tao; Li, Chenlin; Pi, Jinhong; Sheng, Ningyue

    2018-05-01

    This paper reports the application and microstructure refining effect of an Al-2La-1B grain refiner in Al-10Si-0.3Mg casting alloy. Compared with the traditional Al-5Ti-1B refiner, Al-2La-1B refiner shows better performances on the grain refinement of Al-10Si-0.3Mg alloy. Transmission electron microscopy analysis suggests that the crystallite structure features of LaB6 are beneficial to the heterogeneous nucleation of α-Al grains. Regarding the mechanical performances, tensile properties of Al-10Si-0.3Mg casting alloy are prominently improved, due to the refined microstructures.

  20. Theoretical analysis of compatibility of several reinforcement materials with NiAl and FeAl matrices

    Science.gov (United States)

    Misra, Ajay K.

    1989-01-01

    Several potential reinforcement materials were assessed for their chemical, coefficient of thermal expansion (CTE), and mechanical compatibility with the intermetallic matrices based on NiAl and FeAl. Among the ceramic reinforcement materials, Al2O3, TiC, and TiB2, appear to be the optimum choices for NiAl and FeAl matrices. However, the problem of CTE mismatch with the matrix needs to be solved for these three reinforcement materials. Beryllium-rich intermetallic compounds can be considered as potential reinforcement materials provided suitable reaction barrier coatings can be developed for these. Based on preliminary thermodynamic calculations, Sc2O3 and TiC appear to be suitable as reaction barrier coatings for the beryllides. Several reaction barrier coatings are also suggested for the currently available SiC fibers.

  1. AlGaN-based deep-ultraviolet light-emitting diodes grown on high-quality AlN template using MOVPE

    KAUST Repository

    Yan, Jianchang; Wang, Junxi; Zhang, Yun; Cong, Peipei; Sun, Lili; Tian, Yingdong; Zhao, Chao; Li, Jinmin

    2015-01-01

    In this article, we report the growth of high-quality AlN film using metal-organic vapor phase epitaxy. Three layers of middle-temperature (MT) AlN were introduced during the high-temperature (HT) AlN growth. During the MT-AlN layer growth, aluminum and nitrogen sources were closed for 6 seconds after every 5-nm MT-AlN, while H2 carrier gas was always on. The threading dislocation density in an AlN epi-layer on a sapphire substrate was reduced by almost half. AlGaN-based deep-ultraviolet light-emitting diodes were further fabricated based on the AlN/sapphire template. At 20 mA driving current, the emitted peak wavelength is 284.5 nm and the light output power exceeds 3 mW.

  2. AlGaN-based deep-ultraviolet light-emitting diodes grown on high-quality AlN template using MOVPE

    KAUST Repository

    Yan, Jianchang

    2015-03-01

    In this article, we report the growth of high-quality AlN film using metal-organic vapor phase epitaxy. Three layers of middle-temperature (MT) AlN were introduced during the high-temperature (HT) AlN growth. During the MT-AlN layer growth, aluminum and nitrogen sources were closed for 6 seconds after every 5-nm MT-AlN, while H2 carrier gas was always on. The threading dislocation density in an AlN epi-layer on a sapphire substrate was reduced by almost half. AlGaN-based deep-ultraviolet light-emitting diodes were further fabricated based on the AlN/sapphire template. At 20 mA driving current, the emitted peak wavelength is 284.5 nm and the light output power exceeds 3 mW.

  3. Synthesis and characterization of high volume fraction Al-Al2O3 nanocomposite powders by high-energy milling

    International Nuclear Information System (INIS)

    Prabhu, B.; Suryanarayana, C.; An, L.; Vaidyanathan, R.

    2006-01-01

    Al-Al 2 O 3 metal matrix composite (MMC) powders with volume fractions of 20, 30, and 50% Al 2 O 3 were synthesized by high-energy milling of the blended component powders. The particle sizes of Al 2 O 3 studied were 50 nm, 150 nm, and 5 μm. A uniform distribution of the Al 2 O 3 reinforcement in the Al matrix was successfully obtained after milling the powders for a period of 20 h at a ball-to-powder ratio of 10:1 in a SPEX mill. The uniform distribution of Al 2 O 3 in the Al matrix was confirmed by characterizing these nanocomposite powders by scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), X-ray mapping, and X-ray diffraction (XRD) techniques

  4. Atomic-scale microstructures of Zr2Al3C4 and Zr3Al3C5 ceramics

    International Nuclear Information System (INIS)

    Lin, Z.J.; Zhuo, M.J.; He, L.F.; Zhou, Y.C.; Li, M.S.; Wang, J.Y.

    2006-01-01

    The microstructures of bulk Zr 2 Al 3 C 4 and Zr 3 Al 3 C 5 ceramics have been investigated using transmission electron microscopy and scanning transmission electron microscopy. These two carbides were determined to have a point group 6/mmm and a space group P6 3 /mmc using selected-area electron diffraction and convergent beam electron diffraction. The atomic-scale microstructures of Zr 2 Al 3 C 4 and Zr 3 Al 3 C 5 were investigated through high-resolution imaging and Z-contrast imaging. Furthermore, intergrowth between Zr 2 Al 3 C 4 and Zr 3 Al 3 C 5 was identified. Stacking faults in Zr 3 Al 3 C 5 were found to result from the insertion of an additional Zr-C layer. Cubic ZrC was occasionally identified to be incorporated in elongated Zr 3 Al 3 C 5 grains. In addition, Al may induce a twinned ZrC structure and lead to the formation of ternary zirconium aluminum carbides

  5. Studies on the sedimentation and agglomeration behavior of Al-Ti-B and Al-Ti-C grain refiners

    Energy Technology Data Exchange (ETDEWEB)

    Gazanion, F.; Chen, X.G.; Dupuis, C. [Alcan International Ltd., Jonquiere, PQ (Canada). Arvida Research and Development Centre

    2002-07-01

    The sedimentation and agglomeration behavior of Al-Ti-B and Al-Ti-C grain refiners in liquid aluminum has been investigated using the LiMCA and PoDFA analysis techniques in combination with metallographic examination. The widely used Al-5%Ti-1%B and Al-3%Ti-0.15%C master alloys were chosen. Two aluminum alloys, an AAlxxx (commercially pure metal) and an AA5182 (Al-4.5%Mg) alloy, were prepared with different additions of grain refiners. The difference in particle behavior in liquid aluminum for both refiners is described and briefly analyzed in terms of sensitivity to agglomeration and grain refiner performance. Experimental results indicate that, in comparison with the Al-Ti-B refiner, the Al-Ti-C refiner is detrimentally affected by long holding periods due to the decomposition of TiC particles within the melt. (orig.)

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

    International Nuclear Information System (INIS)

    Munitz, A.; Cotler, A; Talianker, M.

    1998-01-01

    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 4.5x10 25 and 8x10 25 thermal neutrons/m 2 (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 1x10 25 thermal neutrons/m 2 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

  7. Effect of the heating rate on the microstructure of in situ Al2O3 particle-reinforced Al matrix composites prepared via displacement reactions in an Al/CuO system

    International Nuclear Information System (INIS)

    Zhao, Ge; Shi, Zhiming; Ta, Na; Ji, Guojun; Zhang, Ruiying

    2015-01-01

    Highlights: • The heating rate has a significant effect on the microstructures of composites. • The microstructure is determined by the diffusion rate of O and Cu in the heating stage. • The diffusion of Cu and O atoms is influenced by the heating rate. • With increasing heating rate, the Al 2 O 3 particle distribution becomes more uniformly. • With increasing heating rate, the form of Al 2 Cu changes from network to block-like. - Abstract: In this study, an in situ Al 2 O 3 particle-reinforced Al(Cu) matrix composite was successfully synthesized using a displacement reaction between Al and CuO powders. The powders were mixed at a weight ratio of 4:1 Al to CuO, cold-pressed and holding time at 900 °C for 1 h using varying heating rates. The effects of the heating rate on the microstructures of the composites were investigated using differential scanning calorimetry (DSC), X-ray diffraction (XRD), optical microscopy (MO), scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS). The results indicate that all of the composites contain Al, Al 2 O 3 particles and Al 2 Cu phases. Although the heating rate does not significantly affect the phase compositions of the composites, it has a significant effect on their microstructures, most likely because it strongly influences the diffusion rates of the Cu and O atoms. As the heating rate is increased, the Al 2 O 3 particles become more dispersed, and they have a more uniform particle size distribution. Meanwhile, the Al 2 Cu structure transforms from the network (Al + Al 2 Cu) eutectic to the block-like Al 2 Cu phase. The ∼2 μm Al 2 O 3 particles and the block-like Al 2 Cu phase are distributed uniformly in the Al matrix when the sample is placed directly into a 900 °C furnace. This sample has a relative higher Rockwell hardness B (HRB) value of 87

  8. Bulk-compositional changes of Ni2Al3 and NiAl3 during ion etching

    International Nuclear Information System (INIS)

    Chen Houwen; Wang Rong

    2008-01-01

    Bulk-compositional changes of Ni 2 Al 3 and NiAl 3 in a Ni-50 wt% Al alloy during ion etching have been investigated by transmission electron microscopy and energy dispersive X-ray spectroscopic analyses. After etching with 7, 5 and 3 keV Ar + ions for 15, 24 and 100 h nickel contents in both Ni 2 Al 3 and NiAl 3 exceeded greatly those in the initial compounds and increased with the decrement of the sputtering energy. After 100 h etching with 3 keV Ar + ions the compositions of these two compounds reached a similar value, about Ni 80-83 Al 12-15 Fe 3-4 Cr 1-2 (at%). A synergistic action of preferential sputtering, radiation-induced segregation and radiation-enhanced diffusion enables the altered-layers at the top and bottom of the film extend through the whole film. The bulk-compositional changes are proposed to occur in the unsteady-state sputtering regime of ion etching and caused by an insufficient supply of matter in a thin film

  9. Investigation on Tribological Properties of the Pre-oxidized Ti2AlN/TiAl Composite

    Science.gov (United States)

    Wang, Daqun; Sun, Dongli; Han, Xiuli; Wang, Qing; Wang, Guangwei

    2018-03-01

    Different oxidation layers on the Ti2AlN/TiAl substrate which was fabricated by in situ synthesis were prepared through thermal oxidation process. The microstructure, phase identification and elements distribution of the oxidation layers were analyzed. The tribological performance of pre-oxidized composites against Si3N4 ball at 25 and 600 °C, as well as the effect of pre-oxidation layers on tribological performance was systematically investigated. The results show that, compared to Ti2AlN/TiAl, the pre-oxidized composites present more excellent tribological properties, especially the wear resistance at 600 °C. It is a significant finding that, different from severe abrasive wear and plastic deformation of Ti2AlN/TiAl, the tribo-films formed by the pre-oxidation layers on the worn surface of pre-oxidized composites weaken abrasive wear and suppress the development of plastic deformation to protect the underlying composite substrate from wear. Moreover, the stable cooperation on the interface between tribo-films and Si3N4 ball results in the relatively steady friction coefficient.

  10. Luminescence of delafossite-type CuAlO2 fibers with Eu substitution for Al cations.

    Science.gov (United States)

    Liu, Yin; Gong, Yuxuan; Mellott, Nathan P; Wang, Bu; Ye, Haitao; Wu, Yiquan

    2016-01-01

    CuAlO 2 has been examined as a potential luminescent material by substituting Eu for Al cations in the delafossite structure. CuAlO 2 :Eu 3+ nanofibers have been prepared via electrospinning for the ease of mitigating synthesis requirements and for future optoelectronics and emerging applications. Single-phase CuAlO 2 fibers could be obtained at a temperature of 1100 °C in air. The Eu was successfully doped in the delafossite structure and two strong emission bands at ~405 and 610 nm were observed in the photoluminescence spectra. These bands are due to the intrinsic near-band-edge transition of CuAlO 2 and the f-f transition of the Eu 3+ activator, respectively. Further electrical characterization indicated that these fibers exhibit semiconducting behavior and the introduction of Eu could act as band-edge modifiers, thus changing the thermal activation energies. In light of this study, CuAlO 2 :Eu 3+ fibers with both strong photoluminescence and p-type conductivity could be produced by tailoring the rare earth doping concentrations.

  11. Metode Penafsiran Ibn al-‘Arabî dalam Ahkâm al-Qur’ân

    Directory of Open Access Journals (Sweden)

    Saiful Fahmi

    2015-09-01

    Full Text Available This paper will explain the concept of ontological Ibn al-‘Arabi of interpretation, the general idea of the book Ahkâm al-Qur’ân that includes methods, patterns, sources of interpretation, interpretation elements and characteristics that distinguish it from the interpreters other. Ontological view regarding the interpretation that was never a logical consequence of the importance of the final carry was critical of the existing interpretation of the results so far, so it is legitimate to question whether Ahkâm al-Qur’ân is still relevant to the demands of his time or not? Whether in it there is coercion-coercion and preconceptions-ideological Ibn al-‘Arabî or not? Given, Ahkâm al-Qur’ân is reproduced in the 5th century AH, where the fight discourse between the schools of thought Islam was at its height. While Ibn al-‘Arabi is an intellectual who embrace genuine Mâlikî School, so it brought the prejudice that he is stuck in an ideological reason

  12. Kulturmorphologie als Zivilisationskritik

    DEFF Research Database (Denmark)

    Peters, Rikke Alberg

    2010-01-01

    Der Untergang des Abendlandes wird oft als dasjenige Werk betrachtet, das am tiefsten die national gefärbte Gegenüberstellung von Kultur und Zivilisation in der Zwischenkriegszeit geprägt und propagiert hat. Wie auch bei anderen Autoren der Konservativen Revolution, vor allem bei Thomas Mann und...... Arthur Moeller van den Bruck, tritt der Begriff ‚Kultur’ bei Spengler als normativer Wertbegriff auf, der im Kontrast zu einer degenerierten und seelenlosen Zivilisation steht....

  13. Pitting corrosion of Al and Al-Cu alloys by ClO4- ions in neutral sulphate solutions

    International Nuclear Information System (INIS)

    Amin, Mohammed A.; Abd El Rehim, Sayed S.; Moussa, S.O.; Ellithy, Abdallah S.

    2008-01-01

    The influence of various concentrations of NaClO 4 , as a pitting corrosion agent, on the corrosion behaviour of pure Al, and two Al-Cu alloys, namely (Al + 2.5 wt% Cu) and (Al + 7 wt% Cu) alloys in 1.0 M Na 2 SO 4 solution was investigated by potentiodynamic polarization and potentiostatic techniques at 25 deg. C. Measurements were conducted under the influence of various experimental conditions, complemented by ex situ energy dispersive X-ray (EDX) and scanning electron microscopy (SEM) examinations of the electrode surface. In free perchlorate sulphate solutions, for the three Al samples, the anodic polarization exhibits an active/passive transition. The active dissolution region involves an anodic peak (peak A) which is assigned to the formation of Al 2 O 3 passive film on the electrode surface. The passive region extends up to 1500 mV with almost constant current density (j pass ) without exhibiting a critical breakdown potential or showing any evidence of pitting attack. For the three Al samples, addition of ClO 4 - ions to the sulphate solution stimulates their active anodic dissolution and tends to induce pitting corrosion within the oxide passive region. Pitting corrosion was confirmed by SEM examination of the electrode surface. The pitting potential decreases with increasing ClO 4 - ion concentration indicating a decrease in pitting corrosion resistance. The susceptibility of the three Al samples towards pitting corrosion decreases in the order: Al > (Al + 2.5 wt% Cu) alloy > (Al + 7 wt% Cu) alloy. Potentiostatic measurements showed that the rate of pitting initiation increases with increasing ClO 4 - ion concentration and applied step anodic potential, while it decreases with increasing %Cu in the Al samples. The inhibitive effect of SO 4 2- ions was also discussed

  14. Influence of electric current on microstructure evolution in Ti/Al and Ti/TiAl{sub 3} during spark plasma sintering

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Y. [Department of Materials Science and Engineering, Institute of Materials Science, University of Connecticut, Storrs, CT 06269-3136 (United States); Haley, J. [Department of Chemical Engineering and Materials Science, University of California, Davis, CA 95616-5294 (United States); Kulkarni, K. [Department of Materials Science and Engineering, Indian Institute of Technology, Kanpur 208016, UP (India); Aindow, M. [Department of Materials Science and Engineering, Institute of Materials Science, University of Connecticut, Storrs, CT 06269-3136 (United States); Lavernia, E.J., E-mail: lavernia@ucdavis.edu [Department of Chemical Engineering and Materials Science, University of California, Davis, CA 95616-5294 (United States); Department of Chemical Engineering and Materials Science, University of California, Irvine, CA 92697-2575 (United States)

    2015-11-05

    The synthesis of γ-TiAl from elemental metals via solid-state reactive diffusion processing routes involves multiple reaction steps with the formation of various intermediate intermetallic compounds, starting with TiAl{sub 3} because this phase is favored kinetically. To understand the processes by which the TiAl{sub 3} intermediate is eliminated during synthesis of γ-TiAl alloy via spark plasma sintering (SPS), the reaction between Ti and TiAl{sub 3} during SPS was studied with emphasis on the effects of the applied electric current and starting TiAl{sub 3} microstructure on the reaction kinetics and the underlying diffusion mechanisms. The intermediate intermetallic phases Ti{sub 3}Al, TiAl and TiAl{sub 2} were formed between the Ti and TiAl{sub 3} upon SPS processing at 900 °C. The applied electric current did not alter the character of the phases formation in the Ti/TiAl{sub 3} system, but thermodynamic calculations suggest that the activation energy for the nucleation of TiAl{sub 2} is reduced significantly with an electric current flowing. Moreover, the kinetics of the reactions between Ti and TiAl{sub 3} were enhanced when the starting TiAl{sub 3} microstructure was refined. The electric field also had a more significant influence on the grain growth kinetics for TiAl{sub 2} and TiAl in powder blend compacts with refined microstructures. - Highlights: • Reaction between Ti and TiAl{sub 3} during spark plasma sintering was studied. • Refined starting TiAl{sub 3} microstructure enhanced the reactions kinetics. • The nucleation barrier of TiAl{sub 2} was reduced by the applied electric field. • The applied electric field restrained the grain growth of TiAl and TiAl{sub 2}.

  15. A first-principles study of the SCN− chemisorption on the surface of AlN, AlP, and BP nanotubes

    International Nuclear Information System (INIS)

    Soltani, Alireza; Taghartapeh, Mohammad Ramezani; Mighani, Hossein; Pahlevani, Amin Allah; Mashkoor, Reza

    2012-01-01

    Graphical abstract: Adsorption properties of SCN − on AlN, AlP, and BP nanotubes based on density functional theory. ▶ We demonstrate the most stable configurations (N-side) of SCN − on AlN, AlP, and BP nanotubes models. Highlights: ► The SCN − Adsorption on surface of AlN, AlP, and BP nanotubes were studied via density functional theory (DFT). ► The interaction of SCN − on the electronic properties and the NBO charge distribution of mentioned configurations are investigated. ► The studies suggest that the adsorption energies of SCN − on AlPNT is most notable in comparison with AlNNT and BPNT. - Abstract: We have performed first-principles calculations to explore the adsorption behavior of the SCN − on electronic properties of AlN, AlP, and BP nanotubes. The adsorption value of SCN − for the most stable formation on the AlPNT is about −318.16 kJ mol −1 , which is reason via the chemisorptions of SCN anion. The computed density of states (DOS) indicates that a notable orbital hybridization take place between SCN − and AlP nanotube in adsorption process. Finally, the AlP nanotube can be used to design as useful sensor for nanodevice applications.

  16. α-NiPt(Al) and phase equilibria in the Ni-Al-Pt system at 1150 deg C

    International Nuclear Information System (INIS)

    Hayashi, S.; Ford, S.I.; Young, D.J.; Sordelet, D.J.; Besser, M.F.; Gleeson, B.

    2005-01-01

    The α-NiPt(Al) phase and its associated equilibria in the Ni-Al-Pt system at 1150 deg C were investigated by analyzing equilibrated bulk alloys and the interdiffusion zones of diffusion couples. Phase constitutions, tie-lines and microstructures were determined using a combination of techniques, including high-energy synchrotron X-ray diffraction, scanning electron microscopy and electron probe microanalysis. A large Pt solubility limit was found to exist in the β-NiAl, ∼42 at.%, and in γ'-Ni 3 Al, ∼32 at.%. The α-NiPt(Al) phase was found to have wide Pt solubility range of about 33-60 at.% and to skew along an almost constant Pt/Al ratio of 1.5. The α-NiPt(Al) has an ordered face-centered tetragonal L1 0 crystal structure, with the Al and Pt atoms found to be preferentially located in the corners and prismatic faces, respectively. The temperature dependence of the lattice parameters and unit cell volume of the α phase were also determined

  17. 26Al/sup g,m/ production cross sections from the 23Na(α,n)26Al reaction

    International Nuclear Information System (INIS)

    Norman, E.B.; Chupp, T.E.; Lesko, K.T.; Schwalbach, P.; Grant, P.J.

    1981-01-01

    Cross sections have been determined for the production of 26 Al/sup g,m/ from the 23 Na(α,n) reaction. Total 26 Al production cross sections were obtained from measurements of the thick-target neutron yield. 26 Al/sup m/ cross sections were measured using an activation technique. 26 Al/sup g/ cross sections were deduced by subtracting the 26 Al/sup m/ cross sections from the total (α,n) cross sections. The principle of detailed balance has been applied to the low energy data to obtain cross sections for the astrophysically interesting 26 Al/sup g/(n,α 0 ) 23 Na reaction. These results are compared with the results of Hauser-Feshbach calculations

  18. Discharge behaviour of Mg-Al-Pb and Mg-Al-Pb-In alloys as anodes for Mg-air battery

    International Nuclear Information System (INIS)

    Wang, Naiguang; Wang, Richu; Peng, Chaoqun; Peng, Bing; Feng, Yan; Hu, Chengwang

    2014-01-01

    Highlights: • We investigate the effect of indium on the discharge behaviour of Mg-Al-Pb alloy. • We evaluate the performance of Mg-air batteries with Mg-Al-Pb and Mg-Al-Pb-In anodes. • We analyze the activation mechanism of Mg-Al-Pb-In alloy in the discharge process. - Abstract: The discharge behaviour of Mg-Al-Pb and Mg-Al-Pb-In alloys in 3.5 wt.% NaCl solution is investigated by electrochemical techniques, and compared with that of pure magnesium. The results show that Mg-Al-Pb-In alloy provides a more negative potential and exhibits a higher utilization efficiency in contrast with Mg-Al-Pb alloy and pure magnesium during the half-cell test at a large current density, and gives desirable discharge performance when used as anode for Mg- air battery. The peak power density of the Mg-air battery with Mg-Al-Pb-In anode is 94.5 mW cm −2 , which is comparable with those of Mg-H 2 O 2 semi-fuel batteries. Moreover, the activation mechanism of Mg-Al-Pb-In alloy during the discharge process is also analyzed

  19. The extraordinary role of the AlN interlayer in growth of AlN sputtered on Ti electrodes

    NARCIS (Netherlands)

    Tran, Tuan; Pandraud, G.; Tichelaar, F.D.; Nguyen, Duc Minh; Schellevis, H.; Sarro, P.M.

    2013-01-01

    The structure of AlN layers grown on Ti with and without an AlN interlayer between the Si substrate and the Ti layer is investigated. The AlN grains take over the orientation of the Ti columnar grains in both cases. Surprisingly, the Ti grains do not take over completely the orientations of the AlN

  20. High quality InAsSb grown on InP substrates using AlSb/AlAsSb buffer layers

    International Nuclear Information System (INIS)

    Wu, B.-R.; Liao, C.; Cheng, K. Y.

    2008-01-01

    High quality InAsSb grown on semi-insulating InP substrates by molecular beam epitaxy was achieved using AlSb/AlAsSb structure as the buffer layer. A 1000 A InAsSb layer grown on top of 1 μm AlSb/AlAsSb buffer layer showed a room temperature electron mobility of ∼12 000 cm 2 /V s. High structural quality and low misfit defect density were also demonstrated in the InAsSb layer. This novel AlSb/AlAsSb buffer layer structure with the AlAsSb layer lattice matched to InP substrates could enhance the performance of optoelectronic devices utilizing 6.1 A family of compound semiconductor alloys

  1. Does Al Qaeda Central Still Matter?

    Directory of Open Access Journals (Sweden)

    Kangil Lee

    2015-01-01

    Full Text Available El artículo discute si Al Qaeda central es todavía relevante o no. Tras estudiar la actividades de Al Qaeda central cuyo objetivo es provocar la violencia en Afganistán y Pakistán, así como los planes continuos de ataques directos contra los Estados Unidos, el artículo muestra que la capacidad operativa de Al Qaeda es más sólida y fuerte que la que Estados Unidos y otros investigadores y eruditos han anticipado. Además, el apoyo virulento y la contribución Al Qaeda en la Península Arábiga a la red de Al Qaeda muestra que la longevidad de Al Qaeda depende de la relación con sus afiliados. El artículo concluye que, en estas condiciones, Al Qaeda central todavía ocupa un lugar en las discusiones de seguridad global.

  2. The ALS-FTD-Q: A new screening tool for behavioral disturbances in ALS

    NARCIS (Netherlands)

    Raaphorst, J.; Beeldman, E.; Schmand, B.; Berkhout, J.; Linssen, W.H.J.P.; Van den Berg, L.H.; Pijnenburg, Y.A.L.; Grupstra, H.F.; Weikamp, J.G.; Schelhaas, H.J.; Papma, J.M.; van Swieten, J.C.; de Visser, M.; de Haan, R.J.

    2012-01-01

    Objective: The assessment of behavioral disturbances in amyotrophic lateral sclerosis (ALS) is important because of the overlap with the behavioral variant of frontotemporal dementia (ALS-bvFTD). Motor symptoms and dysarthria are not taken into account in currently used behavioral questionnaires. We

  3. The ALS-FTD-Q: a new screening tool for behavioural disturbances in ALS

    NARCIS (Netherlands)

    Raaphorst, J.; Beeldman, E.; Schmand, B.; Berkhout, J.; Linssen, W.H.J.P.; van den Berg, L.H.; Pijnenburg, Y.A.; Grupstra, H.F.; Weikamp, J.G.; Schelhaas, H.J.; Papma, J.M.; van Swieten, J.C.; de Visser, M.; de Haan, R.J.

    2012-01-01

    Objective: The assessment of behavioral disturbances in amyotrophic lateral sclerosis (ALS) is important because of the overlap with the behavioral variant of frontotemporal dementia (ALS-bvFTD). Motor symptoms and dysarthria are not taken into account in currently used behavioral questionnaires. We

  4. The ALS-FTD-Q A new screening tool for behavioral disturbances in ALS

    NARCIS (Netherlands)

    Raaphorst, Joost; Beeldman, Emma; Schmand, Ben; Berkhout, Joris; Linssen, Wim H. J. P.; van den Berg, Leonard H.; Pijnenburg, Yolande A.; Grupstra, Hepke F.; Weikamp, Janneke G.; Schelhaas, H. Jurgen; Papma, Janne M.; van Swieten, John C.; de Visser, Marianne; de Haan, Rob J.

    2012-01-01

    Objective: The assessment of behavioral disturbances in amyotrophic lateral sclerosis (ALS) is important because of the overlap with the behavioral variant of frontotemporal dementia (ALS-bvFTD). Motor symptoms and dysarthria are not taken into account in currently used behavioral questionnaires. We

  5. The ALS-FTD-Q: a new screening tool for behavioral disturbances in ALS

    NARCIS (Netherlands)

    Raaphorst, J.; Beeldman, E.; Schmand, B.A.; Berkhout, J.; Linssen, W.H.J.P.; Berg, L.H. van den; Pijnenburg, Y.A.; Grupstra, H.F.; Weikamp, J.G.; Schelhaas, H.J.; Papma, J.M.; van Swieten, J.C.; Visser, M. de; Haan, R.J. de

    2012-01-01

    OBJECTIVE: The assessment of behavioral disturbances in amyotrophic lateral sclerosis (ALS) is important because of the overlap with the behavioral variant of frontotemporal dementia (ALS-bvFTD). Motor symptoms and dysarthria are not taken into account in currently used behavioral questionnaires. We

  6. Erosion resistance of FeAl-TiB2 and FeAl-WC at room and elevated temperatures

    International Nuclear Information System (INIS)

    Alman, D.E.; Tylczak, J.H.; Hawk, J.A.

    2000-01-01

    The resistance of FeAl-40%TiB 2 and FeAl-80%WC cermets to solid particle erosion at 25, 180, 500 and 700 C was evaluated and compared to the behavior of WC-6%Co (Co-90%WC) cemented carbides. Even though the WC-Co contained a higher volume fraction of the hard phase, the erosion rates of the FeAl-cermets were similar in magnitude to the erosion rates of the WC-Co. However, the erosion rates of the FeAl-cermets either were constant (FeAl-TiB 2 ) or decreased (FeAl-WC) with increasing test temperature; whereas, the erosion rates of the WC-Co cemented carbides increased with increasing test temperature. This indicated that once the microstructures of the FeAl-cermets are optimized for wear resistance, these materials might make promising candidates for high-temperature wear applications

  7. KONFIGURASI KATA SAM’, BASHAR, DAN FU’AD DALAM AL-QUR’AN MENURUT TINJAUAN ILM AL-MA’ANIY

    Directory of Open Access Journals (Sweden)

    Mahfudz Siddiq

    2011-10-01

    Full Text Available In language and literature perspective, the Qur′anic style has uniqueness because it has specific characteristic, model, and configuration in its style, word, and structure. Al-Qur′an as a miracle of the God revealed to Muhammad peace be upon him is a miracle text of language and literature, although it can not be categorized as literary text, but it uses literary approach in delivering God ideas about world life and hereafter. In this article, the writer tries to discover Qur′anic uniqueness to observe tree words that are always mentioned in a series; sam’ (hear, bashar (see, and fu′aad (heart. In this case, the writer uses al-ma’aaniy, one of al-balaghah branches to analyze Qur′anic verses. The aim is to explain uniqueness of its specific characteristic, model, and configuration used in Qur′anic style in order to explain those tree words. The findings are that the expression of those three words expressed in a series, are revealed in six verses. (1 Surah al-Nahl (16 ayat 78; (2 Surah al-Isra′ (17 ayat 36; (3 Surah al-Mu’minun (23 ayat 78; (4 Surah al-Sajdah (32 ayat 9; (5 Surah al-Ahiqaf (46 ayat 26; dan (6 Surah al-Mulk (67 ayat 23. The sense expressions have reached the perfectness, fashahah or the harmony and compactness among one phrase and the next phrase. In other word the fashahah and balaghah of the Al Quran is incomparable.

  8. Self-forming Al oxide barrier for nanoscale Cu interconnects created by hybrid atomic layer deposition of Cu–Al alloy

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jae-Hyung; Han, Dong-Suk; Kang, You-Jin [Division of Nanoscale Semiconductor Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Shin, So-Ra; Park, Jong-Wan, E-mail: jwpark@hanyang.ac.kr [Division of Materials Science and Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of)

    2014-01-15

    The authors synthesized a Cu–Al alloy by employing alternating atomic layer deposition (ALD) surface reactions using Cu and Al precursors, respectively. By alternating between these two ALD surface chemistries, the authors fabricated ALD Cu–Al alloy. Cu was deposited using bis(1-dimethylamino-2-methyl-2-butoxy) copper as a precursor and H{sub 2} plasma, while Al was deposited using trimethylaluminum as the precursor and H{sub 2} plasma. The Al atomic percent in the Cu–Al alloy films varied from 0 to 15.6 at. %. Transmission electron microscopy revealed that a uniform Al-based interlayer self-formed at the interface after annealing. To evaluate the barrier properties of the Al-based interlayer and adhesion between the Cu–Al alloy film and SiO{sub 2} dielectric, thermal stability and peel-off adhesion tests were performed, respectively. The Al-based interlayer showed similar thermal stability and adhesion to the reference Mn-based interlayer. Our results indicate that Cu–Al alloys formed by alternating ALD are suitable seed layer materials for Cu interconnects.

  9. Self-forming Al oxide barrier for nanoscale Cu interconnects created by hybrid atomic layer deposition of Cu–Al alloy

    International Nuclear Information System (INIS)

    Park, Jae-Hyung; Han, Dong-Suk; Kang, You-Jin; Shin, So-Ra; Park, Jong-Wan

    2014-01-01

    The authors synthesized a Cu–Al alloy by employing alternating atomic layer deposition (ALD) surface reactions using Cu and Al precursors, respectively. By alternating between these two ALD surface chemistries, the authors fabricated ALD Cu–Al alloy. Cu was deposited using bis(1-dimethylamino-2-methyl-2-butoxy) copper as a precursor and H 2 plasma, while Al was deposited using trimethylaluminum as the precursor and H 2 plasma. The Al atomic percent in the Cu–Al alloy films varied from 0 to 15.6 at. %. Transmission electron microscopy revealed that a uniform Al-based interlayer self-formed at the interface after annealing. To evaluate the barrier properties of the Al-based interlayer and adhesion between the Cu–Al alloy film and SiO 2 dielectric, thermal stability and peel-off adhesion tests were performed, respectively. The Al-based interlayer showed similar thermal stability and adhesion to the reference Mn-based interlayer. Our results indicate that Cu–Al alloys formed by alternating ALD are suitable seed layer materials for Cu interconnects

  10. Slow positrons in single-crystal samples of Al and Al-AlxOy

    Science.gov (United States)

    Lynn, K. G.; Lutz, H.

    1980-11-01

    Well-characterized Al(111) and Al(100) samples were studied with monoenergetic positrons before and after exposure to oxygen. Both positronium-formation and positron-emission curves were obtained for various incident positron energies at sample temperatures ranging from 160-900 K. The orthopositronium decay signal provides a unique signature that the positron has emerged from the surface region of a clean metal. In the clean Al crystals part of the positronium formed near the surface is found to be associated with a temperature-activated process described as the thermally activated detrapping of a positron from a surface state. A simple positron diffusion model, including surface and vacancy trapping, is fitted to the positronium data and an estimate of the binding energy of the positron in this trap is made. The positron diffusion constant is found to have a negative temperature dependence before the onset of positron trapping at thermally generated monovacancies (>500 K), in reasonable agreement with theoretical predictions. The depth of the positron surface state is reduced or positronium is formed in the chemisorbed layer as oxygen is adsorbed on both Al sample surfaces, thus increasing the positronium fraction and decreasing the positron emission. At higher oxygen exposures [>500 L (1 L = 10-6 torr sec)] positron or positronium traps are generated in the overlayer and the positronium fraction is reduced. The amorphous-to-crystalline surface transition of AlxOy on Al is observed between 650 and 800 K by the change in the positronium fraction and is interpreted as the removal of trapping centers in the metal-oxide overlayer. At the higher temperatures and incident energies vacancy trapping is observed by the decrease in the positron diffusion length in both the clean and the underlying Al of the oxygen-exposed samples. Similar vacancy formation enthalpies for Al are extracted in both the clean and oxygen-covered samples by a simple model and are in good

  11. Alles is al uitgevonden

    NARCIS (Netherlands)

    J.G.M. van Marrewijk (Charles)

    1996-01-01

    textabstractDe voordelen van vrijhandel zijn zeer beperkt, al-thans als we de empirische schattingen van vooraanstaande economen en internationale organisaties mogen geloven. Zo worden de voordelen van liberalisatie voor de Europese Unie geraamd op ongeveer 0,5% van het bnp 1. De door het IMF

  12. NAZHARIYAH AL-'AMIL WA TADLAFUR AL-QARA'IN INDA TAMMAM HASAN

    Directory of Open Access Journals (Sweden)

    Taufik Luthfi

    2016-06-01

    Full Text Available The researcher attempts to identify the thoughts of Tamman Hassan concerning Tadhafur Al-Qarain and Amil theories in Arabic language grammar. This research is qualitative descriptive research. The data of this reseach based on Tamman Hassan’s legacy concerning the subject of tadhafur al-qarain. This study is based upon two main subjects, namely analysis of the content of the book and compares with the thoughts of other scholars. The study concluded that the new concept devised by Tammam Hassan called tadhafur al-qarain theory. This theory rejects the concept of ‘amil from classic grammar experts in grammatical analysis and understanding of Arabic texts. Tammam Hassan then replaces the concept of ‘amil, by analysis of the link between ma’na and mabna.DOI : 10.15408/a.v3i1.2911

  13. Electroluminescence of erbium in Al/α-Si:H(Er)/p-c-Si/Al structure

    International Nuclear Information System (INIS)

    Kon'kov, I.O.; Kuznetsov, A.N.; Pak, P.E.; Terukov, E.I.; Granitsyna, L.S.

    2001-01-01

    It is informed for the first time on the observation of the erbium intensive electroluminescence from the amorphous hydrated silicon layer by application of the Al/α-Si:H(Er)/p-c-Si/Al structure in the direct shift mode. The above structure is the n-p-heterostructure with the barrier values of 0.3-0.4 eV for the electrons and 0.9-1.1 eV for the holes. The electroluminescence efficiency is evaluated at the level ∼ 2 x 10 -5 . The electroluminescence effect in the Al/α-Si:H(Er)/p-c-Si/Al structure is connected with the hole tunneling from the crystal silicon by the amorphous silicon localized states with the subsequent release into the valent zone [ru

  14. AL Amyloidosis

    Directory of Open Access Journals (Sweden)

    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

  15. Referral bias in ALS epidemiological studies.

    Science.gov (United States)

    Logroscino, Giancarlo; Marin, Benoit; Piccininni, Marco; Arcuti, Simona; Chiò, Adriano; Hardiman, Orla; Rooney, James; Zoccolella, Stefano; Couratier, Philippe; Preux, Pierre-Marie; Beghi, Ettore

    2018-01-01

    Despite concerns about the representativeness of patients from ALS tertiary centers as compared to the ALS general population, the extent of referral bias in clinical studies remains largely unknown. Using data from EURALS consortium we aimed to assess nature, extent and impact of referral bias. Four European ALS population-based registries located in Ireland, Piedmont, Puglia, Italy, and Limousin, France, covering 50 million person-years, participated. Demographic and clinic characteristics of ALS patients diagnosed in tertiary referral centers were contrasted with the whole ALS populations enrolled in registries in the same geographical areas. Patients referred to ALS centers were younger (with difference ranging from 1.1 years to 2.4 years), less likely to present a bulbar onset, with a higher proportion of familial antecedents and a longer survival (ranging from 11% to 15%) when compared to the entire ALS population in the same geographic area. A trend for referral bias is present in cohorts drawn from ALS referral centers. The magnitude of the possible referral bias in a particular tertiary center can be estimated through a comparison with ALS patients drawn from registry in the same geographic area. Studies based on clinical cohorts should be cautiously interpreted. The presence of a registry in the same area may improve the complete ascertainment in the referral center.

  16. Kritik al-Ghazali terhadap Kekekalan Alam

    Directory of Open Access Journals (Sweden)

    Sahidi Mustafa

    2015-09-01

    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.

  17. ALS and other motor neuron diseases.

    Science.gov (United States)

    Tiryaki, Ezgi; Horak, Holli A

    2014-10-01

    This review describes the most common motor neuron disease, ALS. It discusses the diagnosis and evaluation of ALS and the current understanding of its pathophysiology, including new genetic underpinnings of the disease. This article also covers other motor neuron diseases, reviews how to distinguish them from ALS, and discusses their pathophysiology. In this article, the spectrum of cognitive involvement in ALS, new concepts about protein synthesis pathology in the etiology of ALS, and new genetic associations will be covered. This concept has changed over the past 3 to 4 years with the discovery of new genes and genetic processes that may trigger the disease. As of 2014, two-thirds of familial ALS and 10% of sporadic ALS can be explained by genetics. TAR DNA binding protein 43 kDa (TDP-43), for instance, has been shown to cause frontotemporal dementia as well as some cases of familial ALS, and is associated with frontotemporal dysfunction in ALS. The anterior horn cells control all voluntary movement: motor activity, respiratory, speech, and swallowing functions are dependent upon signals from the anterior horn cells. Diseases that damage the anterior horn cells, therefore, have a profound impact. Symptoms of anterior horn cell loss (weakness, falling, choking) lead patients to seek medical attention. Neurologists are the most likely practitioners to recognize and diagnose damage or loss of anterior horn cells. ALS, the prototypical motor neuron disease, demonstrates the impact of this class of disorders. ALS and other motor neuron diseases can represent diagnostic challenges. Neurologists are often called upon to serve as a "medical home" for these patients: coordinating care, arranging for durable medical equipment, and leading discussions about end-of-life care with patients and caregivers. It is important for neurologists to be able to identify motor neuron diseases and to evaluate and treat patients affected by them.

  18. Comparison of electrical characteristic between AlN/GaN and AlGaN/GaN heterostructure Schottky diodes

    International Nuclear Information System (INIS)

    Lü Yuan-Jie; Feng Zhi-Hong; Gu Guo-Dong; Dun Shao-Bo; Yin Jia-Yun; Han Ting-Ting; Cai Shu-Jun; Lin Zhao-Jun

    2014-01-01

    Ni/Au Schottky contacts on AlN/GaN and AlGaN/GaN heterostructures are fabricated. Based on the measured current—voltage and capacitance—voltage curves, the electrical characteristics of AlN/GaN Schottky diode, such as Schottky barrier height, turn-on voltage, reverse breakdown voltage, ideal factor, and the current-transport mechanism, are analyzed and then compared with those of an AlGaN/GaN diode by self-consistently solving Schrödinger's and Poisson's equations. It is found that the dislocation-governed tunneling is dominant for both AlN/GaN and AlGaN/GaN Schottky diodes. However, more dislocation defects and a thinner barrier layer for AlN/GaN heterostructure results in a larger tunneling probability, and causes a larger leakage current and lower reverse breakdown voltage, even though the Schottky barrier height of AlN/GaN Schottky diode is calculated to be higher that of an AlGaN/GaN diode. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  19. Microstructure evolution during annealing of TiAl/NiCoCrAl multilayer composite prepared by EB-PVD

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Rubing, E-mail: zrb86411680@126.com [Department of Mechanics, School of Civil Engineering, Beijing Jiaotong University, Beijing 100044 (China); Zhang, Deming [Beijing General Research Institute of Mining and Metallurgy, Beijing 100044 (China); Chen, Guiqing [Center for Composite Materials, Harbin Institute of Technology, Harbin 150001 (China); Wang, Yuesheng [Department of Mechanics, School of Civil Engineering, Beijing Jiaotong University, Beijing 100044 (China)

    2014-07-01

    TiAl/NiCoCrAl laminate composite sheet with a thickness of 0.4–0.6 mm as well as a dimension of 150 mm × 100 mm was fabricated successfully by using electron beam physical vapor deposition (EB-PVD) method. The annealing treatment was processed at 1123 and 1323 K for 3 h in a high vacuum atmosphere, respectively. The phase composition and microstructure of TiAl/NiCoCrAl microlaminated sheet have been analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Based on the sheet characterization and results of the microstructure evolution during annealing treatment process, the diffusion mechanism of interfacial reaction in TiAl/NiCoCrAl microlaminate was investigated and discussed.

  20. The Effectiveness of Al-Si Coatings for Preventing Interfacial Reaction in Al - Mg Dissimilar Metal Welding

    OpenAIRE

    Wang, Yin; Al-Zubaidy, Basem; Prangnell, Philip

    2017-01-01

    The dissimilar welding of aluminum to magnesium is challenging because of the rapid formation of brittle intermetallic compounds (IMC) at the weld interface. An Al-Si coating interlayer was selected to address this problem, based on thermodynamic calculations that predicted silicon would change the reaction path to avoid formation of the normally observed binary Al-Mg IMC phases (-Al3Mg2 and -Al12Mg17). Long-term static heat treatments confirmed that a Si-rich coating will preferentially pr...

  1. Raman scattering and lattice stability of NaAlH{sub 4} and Na{sub 3}AlH{sub 6}

    Energy Technology Data Exchange (ETDEWEB)

    Yukawa, H. [Department of Materials Science and Engineering, Graduate School of Engineering, Nagoya University, Chikusa-Ku, Nagoya 464-8603 (Japan)], E-mail: hiroshi@numse.nagoya-u.ac.jp; Morisaku, N.; Li, Y.; Komiya, K.; Rong, R.; Shinzato, Y. [Department of Materials Science and Engineering, Graduate School of Engineering, Nagoya University, Chikusa-Ku, Nagoya 464-8603 (Japan); Sekine, R. [Department of Chemistry, Faculty of Science, Shizuoka University, 836 Ohya, Shizuoka 422-8529 (Japan); Morinaga, M. [Department of Materials Science and Engineering, Graduate School of Engineering, Nagoya University, Chikusa-Ku, Nagoya 464-8603 (Japan)

    2007-10-31

    In situ Raman spectroscopy measurements have been performed during the decomposition of NaAlH{sub 4} in order to investigate the transition from the four-coordinated complex anion, [AlH{sub 4}]{sup -}, in NaAlH{sub 4} to the six-coordinated complex anion, [AlH{sub 6}]{sup 3-}, in Na{sub 3}AlH{sub 6}. Also, the local geometry and the Al-H vibrations are analyzed theoretically by the first-principle calculations of the electronic structures. It is found that the Raman sift at 1765 cm{sup -1} for the Al-H stretching vibration in NaAlH{sub 4} shifts towards the higher frequency side, 1801 cm{sup -1} upon melting. This Raman spectrum for the liquid phase recovers to the original position when it is cooled down to room temperature before Na{sub 3}AlH{sub 6} start to appear. The Raman peak around 1800 cm{sup -1} is still observed after the decomposition of NaAlH{sub 4} occurs to precipitate Na{sub 3}AlH{sub 6}. However, this peak does not recover to its original position by cooling, but still persists in the sample cooled down to room temperature. From these results, the intermediate transition state during the decomposition of NaAlH{sub 4} into Na{sub 3}AlH{sub 6} is discussed. In addition, it is shown from a series of calculation that the highest frequency of the Al-H vibration correlates with the shortest Al-H bond length in the MAlH{sub 4}-type and its derivative complex hydrides.

  2. Evaluation of aerial microbial pollutants in Al-Haram Al-Nabawi during pilgrimage of 2013

    Directory of Open Access Journals (Sweden)

    Kholoud M. Alananbeh

    2017-01-01

    Full Text Available Al-Madinah Al-Munawwarah is the second holiest site in Islam. The possibility of new emerging microbes is valid due to the increased number of pilgrims. The objectives of the current study were to estimate the numbers of fungi and bacteria inside and outside Al-Haram Al-Nabawi and to find whether new bacterial and fungal species have emerged compared to previous studies. Air samples were collected twice a day from 12 spots and four directions during the pilgrim year of 2013 for four consecutive weeks by using the sedimentation method. Thirty five genera and fifty eight species were identified. The most recovered bacterial genera were Staphylococcus, Micrococcus, Bacillus, and Dermacoccus with 32.47%, 18.18%, 12.85%, and 11.23%, respectively. Fifty nine isolates of fungi were molecularly identified. Aspergillus species had the highest percentage (78%. The other fungal genera identified (Alternaria triticina, Emericella nidulans, Emericella striata, Mucor circinelloides, Penicillium chrysogenum, Penicillium minioluteum, Rhizopus arrhizus, Rhizopus oryzae, and Syncephalastrum racemosum had less than 5% frequency. In places such as Al-Haram Al-Nabawi, a large and crowded public (millions exist especially during pilgrimages and Ramadan, thus, exposure to microorganisms is high. On the other hand, microorganism infectivity depends on many factors including their virulence, landing site, and person’s immunity. For those reasons, many aspects should be considered to avoid aerosol contaminants.

  3. AlN and Al oxy-nitride gate dielectrics for reliable gate stacks on Ge and InGaAs channels

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Y.; Li, H.; Robertson, J. [Engineering Department, Cambridge University, Cambridge CB2 1PZ (United Kingdom)

    2016-05-28

    AlN and Al oxy-nitride dielectric layers are proposed instead of Al{sub 2}O{sub 3} as a component of the gate dielectric stacks on higher mobility channels in metal oxide field effect transistors to improve their positive bias stress instability reliability. It is calculated that the gap states of nitrogen vacancies in AlN lie further away in energy from the semiconductor band gap than those of oxygen vacancies in Al{sub 2}O{sub 3}, and thus AlN might be less susceptible to charge trapping and have a better reliability performance. The unfavourable defect energy level distribution in amorphous Al{sub 2}O{sub 3} is attributed to its larger coordination disorder compared to the more symmetrically bonded AlN. Al oxy-nitride is also predicted to have less tendency for charge trapping.

  4. Influence of Al grain boundaries segregations and La-doping on embrittlement of intermetallic NiAl

    Science.gov (United States)

    Kovalev, Anatoly I.; Wainstein, Dmitry L.; Rashkovskiy, Alexander Yu.

    2015-11-01

    The microscopic nature of intergranular fracture of NiAl was experimentally investigated by the set of electron spectroscopy techniques. The paper demonstrates that embrittlement of NiAl intermetallic compound is caused by ordering of atomic structure that leads to formation of structural aluminum segregations at grain boundaries (GB). Such segregations contain high number of brittle covalent interatomic bonds. The alloying by La increases the ductility of material avoiding Al GB enrichment and disordering GB atomic structure. The influence of La alloying on NiAl mechanical properties was investigated. GB chemical composition, atomic and electronic structure transformations after La doping were investigated by AES, XPS and EELFS techniques. To qualify the interatomic bonds metallicity the Fermi level (EF) position and electrons density (neff) in conduction band were determined in both undoped and doped NiAl. Basing on experimental results the physical model of GB brittleness formation was proposed.

  5. Extruded Al-Al{sub 2}O{sub 3} composites formed in situ during consolidation of ultrafine Al powders: Effect of the powder surface area

    Energy Technology Data Exchange (ETDEWEB)

    Balog, Martin, E-mail: martin.balog@savba.sk [Institute of Materials and Machine Mechanics, Slovak Academy of Sciences, Bratislava (Slovakia); Simancik, Frantisek [Institute of Materials and Machine Mechanics, Slovak Academy of Sciences, Bratislava (Slovakia); Walcher, Martin; Rajner, Walter [NMD - New Materials Development GmbH, St. Pantaleon (Austria); Poletti, Cecilia [Institute of Materials Science and Welding, Graz University of Technology, Kopernikusgasse 24/I, A8010 Graz (Austria)

    2011-11-25

    Highlights: {yields} 25 gas atomised Al 99.5% powders with particle size <10 {mu}m were hot extruded. {yields} The strength of compacts was closely related to powder surface area. {yields} Grain boundary strengthening was enhanced by the presence of in situ Al{sub 2}O{sub 3} dispersoids. {yields} Compacts showed good thermal stability due to grain pinning of Al{sub 2}O{sub 3} dispersoids. - Abstract: Twenty-five samples of commercially available, gas-atomised Al (99.5%) powders with particle sizes <10 {mu}m were hot extruded into Al-Al{sub 2}O{sub 3} composites formed in situ during extrusion. The effect of particle size, surface area, oxygen content and atomisation atmosphere of the powder on the microstructure and mechanical properties of the extruded compacts were studied by Brunauer, Emmett, Teller (BET) analysis, hot gas extraction, scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), transmission electron microscopy (TEM) and tensile tests. Thermal stability of the compacts and the individual strengthening mechanisms operating in the compacts were discussed. It was found that the properties of the compacts stemmed from the extraordinary grain boundary strengthening effect of the ultrafine-grained compacts due to their microstructures. The efficiency of the grain boundary strengthening was significantly enhanced by the presence of nano-metric Al{sub 2}O{sub 3} dispersoids introduced in situ. The strength of the compacts was closely related to the surface area of the powder particles. In addition, the entrapped gasses and chemically bonded humidity had a negative effect on the mechanical properties of the compacts.

  6. Structure of 26Al studied by one - nucleon transfer reaction 27Al(d,t

    Directory of Open Access Journals (Sweden)

    Srivastava Vishal

    2015-01-01

    Full Text Available The excited states of 26Al have been produced and studied using 27Al(d,t reaction with 25 MeV deuteron as projectile. Optical model potential parameters were extracted from the measured elastic scattering angular distribution. Zero range distorted wave Born approximation analysis for the ground and 0.223 MeV states of 26Al have been done. The spectroscopic factors calculated for these states are found to be in good agreement with the previously reported values.

  7. Fenomena Pragmatis Dalam Al-qur’an (Kajian Atas Bentuk Imperatif pada Surah Al-Nur

    Directory of Open Access Journals (Sweden)

    Moh Mukhlas

    2016-01-01

    Full Text Available Meskipun secara bentuk ungkapan sudah dianggap selesai, Al-Qur’an masih bersifat terbuka terhadap interpretasi beragam yang sesuai dengan konteksnya, salah satunya adalah dengan mengkaji secara pragmatis. Pragmatik merupakan salah satu disiplin ilmu bahasa yang memfokuskan kajiannya pada makna yang tidak terlepas dari konteks. Pragmatik juga merupakan kajian dari hubungan antara bahasa dan konteks yang mendasari penjelasan pengertian. Mengingat setiap huruf, kata, bahkan alenia yang ada dalam Al-Qur’an sarat dengan makna, maka kajian fenomena pragmatis di dalam Al-Qur’an perlu dilakukan. Penelitian ini bertujuan untuk mendeskripsikan dan menjelaskan fenomena pragmatis dalam Al-Qur’an yang difokuskan pada kajian imperatif pada surah al-Nur. Secara khusus, penelitian ini bertujuan untuk mendeskripsikan dan menjelaskan (1 struktur imperatif, (2 makna bentuk imperatif, dan (3 faktor yang melatarbelakangi bentuk imperatif dalam surah al-Nur. Untuk menjawab permasalahan di atas, penelitian ini menggunakan jenis penelitian kualitatif. Datanya berupa paparan teks yang diambil dari surah al-Nur. Data dikumpulkan dengan teknik dokumentasi dengan berpedoman pada keabsahan dokumentasi yang berfungsi sebagai instrumen penelitian. Sedangkan analisis data yang digunakan adalah analisis data model alir yang diadopsi dari Milles dan Huberman yang memiliki beberapa langkah kegiatan yang terjadi secara bersamaan, yakni (a pengumpulan data, (b reduksi data, (c penyajian data, dan (d penyimpulan/verifikasi. Dari analisis data ditemukan bahwa: (1 bentuk imperatif tidak selalu menggunakan struktur imperative verb (fi’il amar, tetapi juga menggunakan struktur fi’il mudhari’ yang dijazamkan dengan lam amar, struktur kalimat deklaratif, dan struktur fi’il nahyi (negative imperative; (2 bentuk imperatif yang menggunakan struktur fi’il amar dan fi’il nahyi memiliki makna lokusi yang menyatakan suatu keharusan, baik keharusan melaksanakan atau

  8. Effect of in-situ formed Al3Ti particles on the microstructure and mechanical properties of 6061 Al alloy

    Science.gov (United States)

    Gupta, Rahul; Chaudhari, G. P.; Daniel, B. S. S.

    2018-03-01

    In this study, in situ Titanium-tri-aluminide (Al3Ti) particles reinforced Al 6061 alloy matrix composites were fabricated by the reaction of potassium hexafluorotitanate (K2TiF6) inorganic salt with molten Al 6061 alloy via liquid metallurgy route. The development of in-situ Al3Ti particles and their effects on the mechanical properties such as yield strength (YS), ductility, ultimate tensile strength (UTS) and hardness, and microstructure of Al 6061 alloy were studied. It was observed from the results that in-situ formed Al3Ti particles were blocky in morphology whose average size was around 2.6 ± 1.1 μm. Microstructure studies showed that grain size of Al matrix was reduced due to the nucleating effect of Al3Ti particles. It was observed from the mechanical properties analysis that when the volume fraction of Al3Ti particles was increased, the hardness, UTS and YS of the composites were also increased as compared to that of Al 6061 alloy. An improvement in ductility was observed with the dispersion of Al3Ti particles in base alloy which is contrary to many other composites.

  9. 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.

  10. Ab-initio thermodynamic and elastic properties of AlNi and AlNi3 intermetallic compounds

    Science.gov (United States)

    Yalameha, Shahram; Vaez, Aminollah

    2018-04-01

    In this paper, thermodynamic and elastic properties of the AlNi and AlNi3 were investigated using density functional theory (DFT). The full-potential linearized augmented plane-wave (APW) in the framework of the generalized gradient approximation as used as implemented in the Wien2k package. The temperature dependence of thermal expansion coefficient, bulk modulus and heat capacity in a wide range of temperature (0-1600 K) were investigated. The calculated elastic properties of the compounds show that both intermetallic compounds of AlNi and AlNi3 have surprisingly negative Poisson’s ratio (NPR). The results were compared with other experimental and computational data.

  11. 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 .

  12. NQRS Data for AlDO2 [Al(OD)O] (Subst. No. 0032)

    Science.gov (United States)

    Chihara, H.; Nakamura, N.

    This document is part of Subvolume A `Substances Containing Ag … C10H15' of Volume 48 `Nuclear Quadrupole Resonance Spectroscopy Data' of Landolt-Börnstein - Group III `Condensed Matter'. It contains an extract of Section `3.2 Data tables' of the Chapter `3 Nuclear quadrupole resonance data' providing the NQRS data for AlDO2 [Al(OD)O] (Subst. No. 0032)

  13. A simulation study on the topotactic transformations from aluminophosphate AlPO(4)-21 to AlPO(4)-25.

    Science.gov (United States)

    Li, J; Yu, J; Wang, K; Zhu, G; Xu, R

    2001-11-05

    Aluminophosphate AlPO(4)-21 (AWO), formulated /(CH(3))(2)NH(2)/[Al(3)P(3)O(12)(OH)], has been synthesized solvothermally by using dimethylamine as the template. Single-crystal X-ray diffraction analysis shows that AlPO(4)-21 crystallizes in the monoclinic space group P2(1)/n with a = 8.687(2) A, b = 17.428(5) A, c = 9.159(2) A, beta = 109.60(2) degrees, V = 1306.3(5) A(3), and Z = 4. XRD analysis shows that AlPO(4)-21 transforms to AlPO(4)-25 (ATV) upon calcination at 500 degrees C. The molecular dynamics simulation approach was used to investigate the topotactic transformations from AlPO(4)-21. The simulation study suggests that AlPO(4)-21 is energetically favored to transform to AlPO(4)-25, as well as other hypothetical forms, by the changing of the UUDD chains to the UDUD chains.

  14. Hydrodeoxygenation of furfuryl alcohol over Cu/MgAl and Cu/ZnAl catalysts derived from hydrotalcite-like precursors

    Directory of Open Access Journals (Sweden)

    Natalia Andrea Pino

    2017-01-01

    Full Text Available The aqueous phase hydrodeoxygenation (HDO of furfuryl alcohol over Cu/MgAl and Cu/ZnAl catalysts with different Mg/Al and Zn/Al molar ratios, were investigated. Mg-Al and Zn-Al mixed oxides derived from hydrotalcites precursors were used as supports, which were impregnated with an aqueous solution of copper nitrate by incipient wetness impregnation. The HDO reaction was carried out in a typical batch reactor at 5 MPa of H2 and 200 °C for 4 h. Among the catalysts studied, the Cu/MgAl-0.5 catalyst exhibited the higher furfuryl alcohol conversion (86% and yield of cyclopentanol (35%, which is the reaction product with the highest hydrogen-carbon (H/C ratio. With the Cu/MgAl-3 catalyst a high cyclopentanone yield (67% was achieved. The results obtained, showed that copper supported on mixed oxides catalysts derived from hydrotalcite precursors are a promising alternative to improve the bio-oil quality.

  15. Solidification processing of intermetallic Nb-Al alloys

    Science.gov (United States)

    Smith, Preston P.; Oliver, Ben F.; Noebe, Ronald D.

    1992-01-01

    Several Nb-Al alloys, including single-phase NbAl3 and the eutectic of Nb2Al and NbAl3, were prepared either by nonconsumable arc melting in Ar or by zone processing in He following initial induction melting and rod casting, and the effect of the solidification route on the microstructure and room-temperature mechanical properties of these alloys was investigated. Automated control procedures and melt conditions for directional solidification of NbAl3 and the Nb2Al/Nb3Al eutectic were developed; high purity and stoichiometry were obtained. The effects of ternary additions of Ti and Ni are described.

  16. On the thermal stability of ultrafine-grained Al stabilized by in-situ amorphous Al{sub 2}O{sub 3} network

    Energy Technology Data Exchange (ETDEWEB)

    Balog, Martin, E-mail: martin.balog@savba.sk [Institute of Materials and Machine Mechanics, Slovak Academy of Sciences, Racianska 75, 83102 Bratislava (Slovakia); Department of Chemical Engineering and Materials Science, University of California, Davis, CA 95616 (United States); Hu, Tao [Department of Chemical Engineering and Materials Science, University of California, Davis, CA 95616 (United States); Krizik, Peter [Institute of Materials and Machine Mechanics, Slovak Academy of Sciences, Racianska 75, 83102 Bratislava (Slovakia); Castro Riglos, Maria Victoria [Centro Atómico Bariloche, Av. Bustillo 9.500 (8400) Bariloche, Río Negro (Argentina); Saller, Brandon D.; Yang, Hanry; Schoenung, Julie M.; Lavernia, Enrique J. [Department of Chemical Engineering and Materials Science, University of California, Davis, CA 95616 (United States)

    2015-11-11

    Bulk Al materials with average grain sizes of 0.47 and 2.4 µm, were fabricated by quasi-isostatic forging consolidation of two types of Al powders with average particle sizes of 1.3 and 8.9 μm, respectively. By utilizing the native amorphous Al{sub 2}O{sub 3} (am-Al{sub 2}O{sub 3}) film on the Al powders surfaces, a continuous, ∼7 nm thick, am-Al{sub 2}O{sub 3} network was formed in situ in the Al specimens. Systematic investigation of the changes to the am-Al{sub 2}O{sub 3} network embedded in the Al matrix upon heating and annealing up to 600 °C was performed by transmission electron microscopy (TEM). At the same time, the stability of the Al grain structure was studied by transmission Kikuchi diffraction (TKD), electron back-scatter diffraction (EBSD), and TEM. The am-Al{sub 2}O{sub 3} network remained stable after annealing at 400 °C for 24 h. In-situ TEM studies revealed that at temperatures ≥450 °C, phase transformation of the am-Al{sub 2}O{sub 3} network to crystalline γ-Al{sub 2}O{sub 3} particles occurred. After annealing at 600 °C for 24 h the transformation was completed, whereby only nanometric γ-Al{sub 2}O{sub 3} particles with an average size of 28 nm resided on the high angle grain boundaries of Al. Due to the pinning effect of γ-Al{sub 2}O{sub 3}, the Al grain and subgrain structures remained unchanged during annealing up to 600 °C for 24 h. The effect of the am-Al{sub 2}O{sub 3}→γ-Al{sub 2}O{sub 3} transformation on the mechanical properties of ultrafine- and fine-grained Al is discussed from the standpoint of the underlying mechanisms.

  17. Control of two-dimensional growth of AlN and high Al-content AlGaN-based MQWs for deep-UV LEDs

    Directory of Open Access Journals (Sweden)

    Weihuang Yang

    2013-05-01

    Full Text Available Dense and atomically flat AlN film with root-mean-square roughness value of 0.32 nm was grown on sapphire substrate at a relatively lower temperature by using a three-step epitaxy technique. On the basis of this AlN template, AlGaN-based multiple quantum wells (MQWs with atomically flat hetero-interfaces were epitaxially grown to suppress nonradiative recombination by introducing In as a surfactant during simultaneous source supply. As a result, single intense- and narrow-peaked photoluminescence was obtained from the MQWs. Finally, the deep ultraviolet light emitting diodes with well-behaved I-V characteristic and strong electroluminescence in the range of 256–312 nm were fabricated successfully.

  18. AḤWᾹL AL-QULŪB DALAM KITAB MINHᾹJ AL-ATQIYᾹ’ KARYA KIAI SALEH DARAT

    Directory of Open Access Journals (Sweden)

    Moh In’amuzzahidin

    2016-03-01

    Full Text Available Abstract: This article aims to elaborate the book of Kiai Saleh Darat’s Minhāj al-Atqiyā, a book of mysticism that is still used intraditional Islamic boarding schools (pesantren in Java. The focus of the study is aḥwāl al-qulūb (conditions of heart spiritual, which is part of 'ilm al-mu'āmalah, the second science after the' ilmal-mukāsyafah, a device used for the science to the after life. Aḥwāl al-qulūb can be devided two dimension: commendable and despicable. The commend able is like patience, gratitude, fear, hope, willing, asceticism, piety, qanā'ah, sakhā' (generous, Husnal-zan, Husnal-khulūq, Husnal-mu'āsyarah, sidq, and Ikhlas. Mean while, the despicable is as scared indigent, hate destiny, jealousy, envy, looking sublime, happy and eternal praise in the world, arrogant, riya, covetous, griping, and others. By knowing which ahwalal-Qulub which are commendable and despicable, will facilitate the followers of Sufismactors (Salik to go to the presence of God. In addition, this paper also will discover what it is contribution and relevance of Kiai Saleh Darat’s thought in modern era. Abstrak: Artikel ini bertujuan mengelaborasi kitab Minhāj al-Atqiyā’ Kai Saleh Darat, sebuah kitab tasawuf yang masih digunakan di pesantren-pesantren tradisional di Jawa.Fokus kajian adalah aḥwāl al-qulūb (kondisi spiritual hati yang merupakan bagian dari ‘ilm al-mu‘āmalah, ilmu kedua setelah ‘ilm al-mukāsyafah, sebuah piranti ilmu yang digunakan untuk menuju akhirat. Aḥwāl al-qulūb itu sendiri ada yang terpuji dan ada yang tercela. Adapun yang terpuji adalah seperti ṣabar, syukūr, khauf, rajā’, riḍā, zuhūd, taqwā, qanā‘ah, sakhā’ (dermawan, ḥusn al-ẓan, ḥusn al-khulūq, ḥusn al-mu‘āsyarah, ṣidq, dan ikhlāṣ. Sedangkan aḥwāl al-qulūb yang tercela adalah seperti takut fakir, benci takdir, dengki, iri, mencari keluhuran, senang pujian dan kekal di dunia, takabur, riya, tamak, bakhil, dan

  19. Microarray analysis of peripheral blood lymphocytes from ALS patients and the SAFE detection of the KEGG ALS pathway

    Science.gov (United States)

    2011-01-01

    Background Sporadic amyotrophic lateral sclerosis (sALS) is a motor neuron disease with poorly understood etiology. Results of gene expression profiling studies of whole blood from ALS patients have not been validated and are difficult to relate to ALS pathogenesis because gene expression profiles depend on the relative abundance of the different cell types present in whole blood. We conducted microarray analyses using Agilent Human Whole Genome 4 × 44k Arrays on a more homogeneous cell population, namely purified peripheral blood lymphocytes (PBLs), from ALS patients and healthy controls to identify molecular signatures possibly relevant to ALS pathogenesis. Methods Differentially expressed genes were determined by LIMMA (Linear Models for MicroArray) and SAM (Significance Analysis of Microarrays) analyses. The SAFE (Significance Analysis of Function and Expression) procedure was used to identify molecular pathway perturbations. Proteasome inhibition assays were conducted on cultured peripheral blood mononuclear cells (PBMCs) from ALS patients to confirm alteration of the Ubiquitin/Proteasome System (UPS). Results For the first time, using SAFE in a global gene ontology analysis (gene set size 5-100), we show significant perturbation of the KEGG (Kyoto Encyclopedia of Genes and Genomes) ALS pathway of motor neuron degeneration in PBLs from ALS patients. This was the only KEGG disease pathway significantly upregulated among 25, and contributing genes, including SOD1, represented 54% of the encoded proteins or protein complexes of the KEGG ALS pathway. Further SAFE analysis, including gene set sizes >100, showed that only neurodegenerative diseases (4 out of 34 disease pathways) including ALS were significantly upregulated. Changes in UBR2 expression correlated inversely with time since onset of disease and directly with ALSFRS-R, implying that UBR2 was increased early in the course of ALS. Cultured PBMCs from ALS patients accumulated more ubiquitinated proteins

  20. FTD and ALS: genetic ties that bind.

    Science.gov (United States)

    Orr, Harry T

    2011-10-20

    Curiously, amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), seemingly disparate neurodegenerative disorders, can be inherited together. Two groups (DeJesus-Hernandez et al. and Renton et al.) show that the long sought after ALS/FTD mutation on chromosomal region 9p is a hexanucleotide expansion in C90RF72. These studies, plus a study on X-linked ALS/FTD, provide molecular starting points for identifying pathways that link ALS and FTD pathogenesis. Copyright © 2011 Elsevier Inc. All rights reserved.

  1. ALS-linked mutant SOD1 proteins promote Aβ aggregates in ALS through direct interaction with Aβ.

    Science.gov (United States)

    Jang, Ja-Young; Cho, Hyungmin; Park, Hye-Yoon; Rhim, Hyangshuk; Kang, Seongman

    2017-11-04

    Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by progressive degeneration of motor neurons. Aggregation of ALS-linked mutant Cu/Zn superoxide dismutase (SOD1) is a hallmark of a subset of familial ALS (fALS). Recently, intracellular amyloid-β (Aβ) is detected in motor neurons of both sporadic and familial ALS. We have previously shown that intracellular Aβ specifically interacts with G93A, an ALS-linked SOD1 mutant. However, little is known about the pathological and biological effect of this interaction in neurons. In this study, we have demonstrated that the Aβ-binding region is exposed on the SOD1 surface through the conformational changes due to misfolding of SOD1. Interestingly, we found that the intracellular aggregation of Aβ is enhanced through the direct interaction of Aβ with the Aβ-binding region exposed to misfolded SOD1. Ultimately, increased Aβ aggregation by this interaction promotes neuronal cell death. Consistent with this result, Aβ aggregates was three-fold higher in the brains of G93A transgenic mice than those of non Tg. Our study provides the first direct evidence that Aβ, an AD-linked factor, is associated to the pathogenesis of ALS and provides molecular clues to understand common aggregation mechanisms in the pathogenesis of neurodegenerative diseases. Furthermore, it will provide new insights into the development of therapeutic approaches for ALS. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. When does ALS start? ADAR2-GluA2 hypothesis for the etiology of sporadic ALS

    Directory of Open Access Journals (Sweden)

    Takuto eHideyama

    2011-11-01

    Full Text Available Amyotrophic lateral sclerosis (ALS is the most common adult-onset motor neuron disease. More than 90% of ALS cases are sporadic, and the majority of sporadic ALS patients do not carry mutations in genes causative of familial ALS; therefore, investigation specifically targeting sporadic ALS is needed to discover the pathogenesis. The motor neurons of sporadic ALS patients express unedited GluA2 mRNA at the Q/R site in a disease-specific and motor neuron-selective manner. GluA2 is a subunit of the AMPA receptor, and it has a regulatory role in the Ca2+-permeability of the AMPA receptor after the genomic Q codon is replaced with the R codon in mRNA by adenosine-inosine conversion, which is mediated by adenosine deaminase acting on RNA 2 (ADAR2. Therefore, ADAR2 activity may not be sufficient to edit all GluA2 mRNA expressed in the motor neurons of ALS patients. To investigate whether deficient ADAR2 activity plays pathogenic roles in sporadic ALS, we generated genetically modified mice (AR2 in which the ADAR2 gene was conditionally knocked out in the motor neurons. AR2 mice showed an ALS-like phenotype with the death of ADAR2-lacking motor neurons. Notably, the motor neurons deficient in ADAR2 survived when they expressed only edited GluA2 in AR2/GluR-BR/R (AR2res mice, in which the endogenous GluA2 alleles were replaced by the GluR-BR allele that encoded edited GluA2. In heterozygous AR2 mice with only one ADAR2 allele, approximately 20% of the spinal motor neurons expressed unedited GluA2 and underwent degeneration, indicating that half-normal ADAR2 activity is not sufficient to edit all GluA2 expressed in motor neurons. It is likely therefore that the expression of unedited GluA2 causes the death of motor neurons in sporadic ALS. We hypothesize that a progressive downregulation of ADAR2 activity plays a critical role in the pathogenesis of sporadic ALS and that the pathological process commences when motor neurons express unedited GluA2.

  3. High temperature properties of the Cr-Nb-Al-N coatings with increasing Al contents

    OpenAIRE

    Li, W. Z.; Polcar, T.; Evaristo, M.; Cavaleiro, A.

    2013-01-01

    Cr-Nb-Al-N coatings with Al content from 0 to 12 at.% were deposited by d.c. reactive magnetron sputtering. The coatings were annealed in protective atmosphere at 800 and 900 °C for 1 h and exposed to air at 800, 900 and 1200 °C for different times. The chemical composition, structure, microstructure, hardness and adhesive/cohesive strength of the coatings, in as-deposited and annealed conditions, were investigated and the oxidation resistance was evaluated. As expected, the Al content increa...

  4. A Comparative Study of Carbon Nanotubes Synthesized from Co/Zn/Al and Fe/Ni/Al Catalyst

    Directory of Open Access Journals (Sweden)

    Ezekiel Dixon Dikio

    2011-01-01

    Full Text Available The catalyst systems Fe/Ni/Al and Co/Zn/Al were synthesized and used in the synthesis of carbon nanotubes. The carbon nanotubes produced were characterized by Field Emission Scanning Electron Microscope (FE-SEM, Energy Dispersive x-ray Spectroscopy (EDS, Raman spectroscopy, Thermogravimetric Analysis (TGA and Transmission Electron Microscope (TEM. A comparison of the morphological profile of the carbon nanotubes produced from these catalysts indicates the catalyst system Fe/Ni/Al to have produced higher quality carbon nanotubes than the catalyst system Co/Zn/Al.

  5. TATA CARA PELAKSANAAN SHALAT JUM'AT (Studi Naskah “Sulûk Al-Jâddah Fî Bayân Al-Jum’ah” Karya Syeikh Nawawi al-Bantani

    Directory of Open Access Journals (Sweden)

    Masrukhin Muhsin

    2012-07-01

    Full Text Available Makalah ini merupakan hasil penelitian naskah “Sulûk al-Jâddah Fî Bayân al-Jum’ah” Karya Syeikh Nawawi al-Bantani. Penelitian ini menggunakan pendekatan filologi. Dalam penelitian filologi dikenal dua perlakuan terhadap naskah. Pertama, memperlakukan satu naskah sebagai bagian dari naskah-naskah lainnya yang sejudul. Dalam hal ini semua naskah yang sejudul dikumpulkan di manapun adanya, dengan tujuan mendapatkan naskah asli atau dianggap paling mendekati asli. Kedua, memperlakukan naskah sebagai naskah tunggal. Dalam hal ini peneliti mengesampingkan naskah lain yang kemungkinan ada di tempat lain. Dari dua model tersebut, penelitian ini menggunakan model kedua. Alasannya, naskah Sulûk al-Jâddah fî Bayân al- Jum’ah untuk sementara dinyatakan sebagai naskah tunggal dengan indikasi tidak ditemukan naskah lain. Untuk menganalisa data naskah, dilakukan pembacaan dua tahap, heuristik dan hermeneutik. Adapun pokok-pokok bahasan yang ada dalam naskah Sulûk al-Jâddah fî Bayân al-Jum’ah adalah berisi tentang masalah shalat Jumát dan permasalahan-perasalahan yang dihadapi oleh masyarakat seputar shalat Jum’at dan shalat Jum’at yang diulang.

  6. Examination of the anisotropy of the wetting behaviour of liquid Al-Cu alloys on single crystalline oriented Al{sub 2}O{sub 3}-substrates; Untersuchung der Anisotropie im Benetzungsverhalten fluessiger Al-Cu Legierungen auf einkristallinen orientierten Al{sub 2}O{sub 3}-Substraten

    Energy Technology Data Exchange (ETDEWEB)

    Schmitz, Julianna

    2011-02-04

    The wetting behaviour of liquid Al-Cu alloys and pure metals on oriented single crystalline Al{sub 2}O{sub 3}-substrates was examined, utilising the sessile drop technique. Measurements were performed at moderate temperatures of 1100 C, where the alloys are liquid. Different Al{sub 2}O{sub 3}-surfaces were studied, which are terminated by the crystallographic planes (0001), (11 anti 20), and (1 anti 102), also called C-, A-, and R-surfaces. After deposition, pure Cu-droplets show an exponential increase of the wetting angle to a value of about 115 for all investigated Al{sub 2}O{sub 3}-surfaces. The timescale of this increase is of the order of 100 s. The effect of surface- and interfacial energies on the wetting angle is discussed considering Young's equation. The most probable reason for its time-dependence seems to be an increase of the interfacial energy due to deoxidation of the droplet. Therefore it is reasonable to regard the isotropic contact angle value as the intrinsic one of the Cu/Al{sub 2}O{sub 3} system. In contrast, the wetting angle of pure Al metal with the different Al{sub 2}O{sub 3}-substrates shows a qualitatively different behaviour. In this system, it rises from about 90 to 115 roughly for C-substrates, twice as fast as in the Cu case but to a comparable value. On the other substrates a wetting angle of about 90 establishes immediately, and no pronounced time dependence is obvious. In order to study changes in the wetting behaviour of Al-Cu-alloys, which is isotropic for Cu and anisotropic for Al-rich alloys, contact angles of Al{sub 50}Cu{sub 50}, Al{sub 30}Cu{sub 70} und Al{sub 17}Cu{sub 83} on Al{sub 2}O{sub 3} were determined. For each alloy composition the wetting angle is about 120 after 300 s. The initial values on distinct surfaces hardly differ and become non-wetting with increasing Cu-content. Hence, anisotropy decreases. To determine the work of adhesion of the solid-liquid interface, the temperature- and composition

  7. Membranas poliméricas de PE-g-MA-Al/AlPO4 impregnado com Fe, Al - utilização na recuperação de efluentes de galvanoplastia

    Directory of Open Access Journals (Sweden)

    Joice Andrade de Araújo

    2014-01-01

    Full Text Available Neste trabalho foram desenvolvidas membranas filtrantes de materiais híbridos de polietileno de alta densidade modificado com anidrido maleico e ionizado com hidróxido de alumínio (PE-g-MA-Al (matriz orgânica e fosfato de alumínio amorfo puro (AlPO4 ou impregnado com ferro e/ou alumínio (fase dispersa inorgânica. Essas membranas foram obtidas nas composições de PE-g-MA-Al (M1, PE-g-MA-Al/AlPO4 (M2, PE-g-MA-Al/AlPO4-Al (M3, PE-g-MA-Al/AlPO4-Fe (M4 e PE-g-MA-Al/AlPO4-Fe,Al (M5, na proporção de 97/3% em massa, pelo método de "casting", usando xileno à quente e sob refluxo, como solvente. As técnicas de espectroscopia na região do infravermelho (FTIR, difração de raios X (DRX, análise termogravimétrica (TGA, análise textural, tensão superficial e microscopia eletrônica de varredura (MEV serviram para comprovar a influência da natureza dos materiais e da metodologia usada na confecção das membranas na incorporação da fase inorgânica na matriz polimérica e nas propriedades dos materiais híbridos resultantes. A aplicação das membranas na recuperação de metais presentes no efluente de galvanoplastia mostrou que a presença do ferro e/ou alumínio influenciou na morfologia e nas propriedades texturais desses materiais, e consequentemente na utilização como membranas mesoporosas de ultrafiltração, com os melhores resultados apresentados por M1 e M3 na recuperação de ferro (32 e 35% e zinco (62 e 60%.

  8. Grain refinement of 7075Al alloy microstructures by inoculation with Al-Ti-B master alloy

    Science.gov (United States)

    Hotea, V.; Juhasz, J.; Cadar, F.

    2017-05-01

    This paper aims to bring some clarification on grain refinement and modification of high strength alloys used in aerospace technique. In this work it was taken into account 7075 Al alloy, and the melt treatment was carried out by placing in the form of master alloy wire ternary AlTiB the casting trough at 730°C. The morphology of the resulting microstructures was characterized by optical microscopy. Micrographs unfinished and finished with pre-alloy containing ternary Al5Ti1B evidence fine crystals, crystal containing no columnar structure and highlights the size of the dendrites, and intermetallic phases occurring at grain boundaries in Al-Zn-Mg-Cu alloy. It has been found that these intermetallic compounds are MgZn2 type. AlTiB master alloys finishing ensures a fine eutectic structure, which determines the properties of hardware and improving the mechanical properties of aluminum alloys used in aeronautical engineering.

  9. Implementasi Kurikulum Kulliyatul Mu’alimin Al-Islamiyah (KMI Di Pondok Pesantren Tarbiyatul Mu’allimien Al-Islamiyah (TMI Al-Amien Prenduan Dan Ma’hadul Mu’allimien Al-Islamiyah (MMI Mathlabul Ulum Jambu Sumenep

    Directory of Open Access Journals (Sweden)

    Fajriyah Fajriyah

    2017-07-01

    Full Text Available Tujuan penelitian ini mendeskripsikan dan memahami: Kurikulum kulliyatul mu’allimin al-islamiyah; Implementasi kurikulum kulliyatul mu’allimin al-islamiyah; Faktor pendukung dan faktor penghambat kurikulum kulliyatul mu’allimin al-islamiyah; dan Strategi mengatasi faktor penghambat kurikulum kulliyatul mu’allimin al-islamiyah. Penelitian ini menggunakan pendekatan kualitatif dengan rancangan penelitian studi multi situs. Hasil penelitian ini yaitu: kurikulum KMI di TMI dan MMI perumusan kurikulum KMI didasarkan filosofi yang tercermin dari visi dan misi yang diturunkan dalam tujuan dan disusun dalam langkah yang opersional. Faktor pendukung: terdapat kedisiplinan yang ditanamkan kepada guru dan santri; SDM yang berkompeten; kepedulian orang tua dan masyarakat; dan  strategi mengatasi faktor penghambat kurikulum KMI di TMI dan MMI, memaksimalkan penggunaan teknologi informasi (IT dalam proses pembelajaran, peningkatan kualitas SDM dengan mengikutsertakan guru dalam pelatihan dan pendidikan di pesantren maupun di luar pesantren. guru berperan aktif. Kata Kunci: Implementasi, Kurikuilum, KMI.   Abstract:   While the purpose of this research are to describe: The curriculum of  kulliyatul mu’allimin al-islamiyah; Implementation of  curriculum of kulliyatul mu’allimin al-islamiyah; Factor of support and factor pursuer of curriculum of kulliyatul mu’allimin al-islamiyah; and Strategy to overcome factor of pursuer of curriculum of kulliyatul mu’allimin al-islamiyah. Results of this research are: curriculum KMI in TMI and MMI: the first, curriculum formulating of KMI based philosophy that taken by vision and mission applied the aim and arranged  in step operational, the curriculum implementation KMI and MMI boarding house as formal education institution and non formal to do learning process for 24 hour, support factor and pursuer factor of curriculum KMI in TMI and MMI,pursuer factor are: minimize boarding house facility; limited

  10. Phase transformations, heat evolution, and atomic diffusion during slow heating of Al-rich Al/Zr multilayered foils

    Energy Technology Data Exchange (ETDEWEB)

    Fisher, Kaitlynn; Barron, S. C.; Knepper, R.; Weihs, T. P., E-mail: weihs@jhu.edu [Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, Maryland 21218-2689 (United States); Bonds, M. A.; Browning, N. D. [Department of Chemical Engineering and Materials Science, University of California, Davis, California 95616 (United States); Condensed Matter and Materials Division, Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Livi, K. J. T. [High-Resolution Analytical Electron Microbeam Facility, Integrated Imaging Center, Johns Hopkins University, Baltimore, Maryland 21218 (United States); Campbell, G. H. [Condensed Matter and Materials Division, Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    2013-12-28

    We describe the energy and sequence of phase transformations in multilayered Al/Zr foils with atomic ratios of 3 Al:1 Zr during low temperature (<350 °C) heat treatments in a differential scanning calorimeter. The initial phase formed is an Al-rich amorphous phase that appears to grow by Zr diffusion through the amorphous phase. The subsequent nucleation and growth of tetragonal Al{sub 3}Zr along the Al/amorphous layer interface is mediated by Al diffusion through the crystalline intermetallic phase. Diffusion coefficients associated with these processes are higher than expected from reports of diffusivities measured at higher temperatures. The inferred heat of formation of the tetragonal Al{sub 3}Zr phase is 1240 ± 40 J/g (53 ± 2 kJ/mol atom). No anomalous variation in the energy or sequence of phase transformations is found with bilayer thickness for samples with bilayer thickness in the range of 17 nm to 90 nm despite anomalies in the bilayer dependence of self-propagating reaction velocities in the same foils.

  11. Phase Constituents and Microstructure of Ti3Al/Fe3Al + TiN/TiB2 Composite Coating on Titanium Alloy

    Science.gov (United States)

    Li, Jianing; Chen, Chuanzhong; Zhang, Cuifang

    Laser cladding of the Fe3Al + B4C/TiN + Al2O3 pre-placed powders on the Ti-6Al-4V alloy can form the Ti3Al/Fe3Al + TiN/TiB2 composite coating, which improved the wear resistance of the Ti-6Al-4V alloy surface. In this study, the Ti3Al/Fe3Al + TiN/TiB2 composite coating has been researched by means of X-ray diffraction and scanning electron microscope. It was found that during the laser cladding process, Al2O3 can react with TiB2, leading to the formations of Ti3Al and B. This principle can be used to improve the Fe3Al + B4C/TiN laser-cladded coating on the Ti-6Al-4V alloy. Furthermore, during the cladding process, C consumed the oxygen in Fe3Al + B4C /TiN + Al2O3 molten pool, which retarded the productions of the redundant metal oxides.

  12. The effect of native Al2O3 skin disruption on properties of fine Al powder compacts

    International Nuclear Information System (INIS)

    Balog, Martin; Poletti, Cecilia; Simancik, Frantisek; Walcher, Martin; Rajner, Walter

    2011-01-01

    Research highlights: → The effect of various powder metallurgy compaction routes on the microstructures and properties of ultra-fine atomized Al powder compacts. → Applied compaction route affects the deformation and fracture of native Al 2 O 3 layer present on the surface of as-atomized powder. → Distribution, morphology and interconnectivity of in situ introduced Al 2 O 3 dispersoids distinctly determine the compacts properties. - Abstract: In the presented study we characterize how various powder metallurgical routes (extrusion, forging, and HIP/sintering) affect the fracture of native Al 2 O 3 layer present on the surface of ultra-fine atomized Al powders. It is shown that the different distribution, morphology and interconnectivity of in situ introduced Al 2 O 3 dispersoids strongly affect the thermal stability and mechanical and thermal properties of subsequent powder compacts.

  13. High pressure studies of A2Mo3O12 negative thermal expansion materials (A2=Al2, Fe2, FeAl, AlGa)

    International Nuclear Information System (INIS)

    Young, Lindsay; Gadient, Jennifer; Gao, Xiaodong; Lind, Cora

    2016-01-01

    High pressure powder X-ray diffraction studies of several A 2 Mo 3 O 12 materials (A 2 =Al 2 , Fe 2 , FeAl, and AlGa) were conducted up to 6–7 GPa. All materials adopted a monoclinic structure under ambient conditions, and displayed similar phase transition behavior upon compression. The initial isotropic compressibility first became anisotropic, followed by a small but distinct drop in cell volume. These patterns could be described by a distorted variant of the ambient pressure polymorph. At higher pressures, a distinct high pressure phase formed. Indexing results confirmed that all materials adopted the same high pressure phase. All changes were reversible on decompression, although some hysteresis was observed. The similarity of the high pressure cells to previously reported Ga 2 Mo 3 O 12 suggested that this material undergoes the same sequence of transitions as all materials investigated in this paper. It was found that the transition pressures for all phase changes increased with decreasing radius of the A-site cations. - Graphical abstract: Overlay of variable pressure X-ray diffraction data of Al 2 Mo 3 O 12 collected in a diamond anvil cell. Both subtle and discontinuous phase transitions are clearly observed. - Highlights: • The high pressure behavior of A 2 Mo 3 O 12 (A=Al, Fe, (AlGa), (AlFe)) was studied. • All compounds undergo the same sequence of pressure-induced phase transitions. • The phase transition pressures correlate with the average size of the A-site cation. • All transitions were reversible with hysteresis. • Previously studied Ga 2 Mo 3 O 12 undergoes the same sequence of transitions.

  14. PENDIDIKAN MENURUT AL-GHAZALI

    Directory of Open Access Journals (Sweden)

    Syamsul Kurniawan

    2016-12-01

    Full Text Available Education reform efforts typically begin with a conceptual perspective before implementation. Thus, developing Islamic education usually begins with a study of a figure and his educational thought. And one of the most influential figures whose thought which has Sufi religious pattern has dominated educational thinking atmosphere over the centuries since his death. The purpose of education according to al-Ghazali was to get closer to Allah. He came with a view that the most noble job is to educate: to become a teacher. Al-Ghazali advised that his students, in the learning process, aim to become scientists who could disseminate their knowledge for the sake of humanity values. Keywords: Al-Ghazali, Thought, Islamic Education.

  15. High-temperature deformation behavior and mechanical properties of rapidly solidified Al-Li-Co and Al-Li-Zr alloys

    International Nuclear Information System (INIS)

    Sastry, S.M.L.; Oneal, J.E.

    1984-01-01

    The deformation behavior at 25-300 C of rapidly solidified Al-3Li-0.6Co and Al-3Li-0.3Zr alloys was studied by tensile property measurements and transmission electron microscopic examination of dislocation substructures. In binary Al-3Li and Al-3Li-Co alloys, the modulus normalized yield stress increases with an increase in temperature up to 150 C and then decreases. The yield stress at 25 C of Al-3Li-0.3Zr alloys is 180-200 MPa higher than that of Al-3Li alloys. However, the yield stress of the Zr-containing alloy decreases drastically with increasing temperatures above 75 C. The short-term yield stresses at 100-200 C of the Al-3Li-based alloys are higher than that of the conventional high-temperature Al alloys. The temperature dependences of the flow stresses of the alloys were analyzed in terms of the magnitudes and temperature dependences of the various strengthening contributions in the two alloys. The dislocation substructures at 25-300 C were correlated with mechanical properties. 19 references

  16. Formation mechanism of Al-depleted bands in MOVPE-AlGaN layer on GaN template with trenches

    Energy Technology Data Exchange (ETDEWEB)

    Kuwano, Noriyuki [Art, Science and Technology Center for Cooperative Research, Kyushu University, Kasuga, Fukuoka 816-8580 (Japan); Department of Applied Science for Electronics and Materials, Kyushu University, Kasuga, Fukuoka 816-8580 (Japan); Ezaki, Tetsuya; Kurogi, Takuya [Department of Applied Science for Electronics and Materials, Kyushu University, Kasuga, Fukuoka 816-8580 (Japan); Miyake, Hideto; Hiramatsu, Kazumasa [Department of Electrical and Electronic Engineering, Mie University, Tsu, Mie 514-8507 (Japan)

    2010-07-15

    A microstructure in an AlGaN/GaN layer was analyzed in detail by means of transmission electron microscopy (TEM) and scanning electron microscopy (SEM) with special attention to the formation of steps on the surface. The AlGaN layer was grown by MOVPE on a GaN template with periodic trenches. It was revealed that there formed were Al-depleted bands in the AlGaN layer. These bands were generated from rather lower regions in the AlGaN layer or those above the trenches, and run upwards. Some of them reached the top surface to connect a macro step. The formation mechanism of the Al-depleted region is discussed in terms of thermodynamics. If the total bonding energy of atoms on the macro step of surface is assumed to be smaller than that of atoms on a flat surface, the Al-depletion can be explained provided that the local equilibrium in concentration is conserved during the growth of AlGaN layer. (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  17. Interface traps at Al2O3/InAlN/GaN MOS-HEMT -on- 200 mm Si

    Science.gov (United States)

    Kumar, Sandeep; Remesh, Nayana; Dolmanan, S. B.; Tripathy, S.; Raghavan, S.; Muralidharan, R.; Nath, Digbijoy N.

    2017-11-01

    We report on the characterization of the interfaces of Al2O3/InAlN/GaN HEMT structure grown on 200 mm diameter silicon using conductance dispersion technique. Irreversible threshold voltage (VTH) shift of up to +∼2.5 V was observed due to the gate stress induced activation of acceptor states. Further, frequency dependent VTH shift during capacitance voltage measurements were also recorded due to the presence of slow traps at InAlN/GaN interface. The conductance dispersion indicated the presence of acceptor traps of the order of ∼4 × 1012 to 7 × 1013 cm-2 eV-1 with a time constant of ∼10 to 350 μs at the InAlN/GaN interface. Trap density at the Al2O3/InAlN was found to be in similar range but with a time constant of ∼2 μs. The presence of high density of traps at InAlN/GaN interface is attributed to the unavoidable growth interruption before the start of InAlN growth.

  18. Candida albicans Agglutinin-Like Sequence (Als) Family Vignettes: A Review of Als Protein Structure and Function

    Science.gov (United States)

    Hoyer, Lois L.; Cota, Ernesto

    2016-01-01

    Approximately two decades have passed since the description of the first gene in the Candida albicans ALS (agglutinin-like sequence) family. Since that time, much has been learned about the composition of the family and the function of its encoded cell-surface glycoproteins. Solution of the structure of the Als adhesive domain provides the opportunity to evaluate the molecular basis for protein function. This review article is formatted as a series of fundamental questions and explores the diversity of the Als proteins, as well as their role in ligand binding, aggregative effects, and attachment to abiotic surfaces. Interaction of Als proteins with each other, their functional equivalence, and the effects of protein abundance on phenotypic conclusions are also examined. Structural features of Als proteins that may facilitate invasive function are considered. Conclusions that are firmly supported by the literature are presented while highlighting areas that require additional investigation to reveal basic features of the Als proteins, their relatedness to each other, and their roles in C. albicans biology. PMID:27014205

  19. Dependences of the Al thickness and annealing temperature on the structural, optical and electrical properties in ZnO/Al multilayers

    International Nuclear Information System (INIS)

    Hu, Y.M.; Lin, C.W.; Huang, J.C.A.

    2006-01-01

    High-quality (0001) oriented ZnO (300 A) film and [ZnO(100 A)/Al(t Al )] 3 (t Al = 0.6, 1.7, 2.8 A) multilayers have been established at room temperature on Al 2 O 3 (0001) substrates by ion-beam sputtering. The structural, optical and electrical properties of multilayers as functions of both the Al thickness and annealing temperature are reported. We have verified that Al thickness and annealing temperature are the key factors to optimize transparency-conducting property in ZnO/Al multilayers. The optimum Al thickness and annealing temperature for ZnO/Al multilayer of 300 A thin is 1.7 A (about one Al atomic layer) and 400 deg. C, respectively, leading to the relatively lower resistivity (2.8 x 10 -3 Ω cm) and higher Hall mobility (10 cm 2 /V.s) without suppression of the visible transmittance (above 85%)

  20. Lubâb At-Ta’wîl ‘Inda Al-Imâm Al-Khâzîn Baina Al-Ma’tsûr wa Ar-Ra’yi (Dirâsah Maudhu’iyyah fi Ayah al-Qashash

    Directory of Open Access Journals (Sweden)

    Muhammad Shulhi Alhadi siregar

    2018-03-01

    Full Text Available This paper concern to study about one of Tafseer book, namely Lubâb al-Ta'wîl fi Ma'âny at-Tanzîl by Imam al-Khazin. Some scholars differ in the setting of sources of tafseer. Such as, the well-known scholars, Muhammad Ali Iyazi and Muhammad Husain ad-Dzahabi. Ulama Iyazi assumes that Tafseer Khazin belongs to the category of commentary bi al-Ma'tsûr, since this commentary is an ikhtishar of Tafseer al-Baghawi. While some scholars such as adz-Dzahabi, categorized this tafseer into the bi al-Ra'yi. By using the tahlily documentation method and the thematic method associated with Qashash verses in the Qur'an, the researchers found the correct method, namely the tafseer of al-Atsary an-Nazhary or known by tafseer bi al-Ma'tsûr who use Ra'yi as an extension of explanation and the determination of the most powerful law, seen from writing theme related at the end of its tafseer.

  1. Case-Detection Rate of Direct Sputum Smear Microscopy for ...

    African Journals Online (AJOL)

    de la culture sur milieu de Löwenstein- Jensen en tant que norme de référence . Sur les 150 participants testés, 51 étaient à frottis positif pour les bacilles acido rapide (taux de positivité, 34,0%, 51/150), tandis que 79 étaient positifs à la culture pour complexe Mycobacterium tuberculosis et 12 pour les mycobactéries non ...

  2. Case series

    African Journals Online (AJOL)

    2012-11-15

    Nov 15, 2012 ... L´agent pathogène est principalement le Mycobacterium tuberculosis ou le bacille de Koch secondairement le Mycobacterium bovis. Il s´agit d´un bacille acido-alcoolo-résistant à croissance lente (temps de dédoublement est de 15à 20 heures), ce qui explique l´évolution lente de la maladie. [5]. L´atteinte ...

  3. Growth and Device Performance of AlGaN/GaN Heterostructure with AlSiC Precoverage on Silicon Substrate

    Directory of Open Access Journals (Sweden)

    Jae-Hoon Lee

    2014-01-01

    Full Text Available A crack-free AlGaN/GaN heterostructure was grown on 4-inch Si (111 substrate with initial dot-like AlSiC precoverage layer. It is believed that introducing the AlSiC layer between AlN wetting layer and Si substrate is more effective in obtaining a compressively stressed film growth than conventional Al precoverage on Si surface. The metal semiconductor field effect transistor (MESFET, fabricated on the AlGaN/GaN heterostructure grown with the AlSiC layer, exhibited normally on characteristics, such as threshold voltage of −2.3 V, maximum drain current of 370 mA/mm, and transconductance of 124 mS/mm.

  4. Comparative study of phase structure and dielectric properties for K0.5Bi0.5TiO3-BiAlO3 and LaAlO3-BiAlO3

    International Nuclear Information System (INIS)

    Hou, Yudong; Zheng, Mupeng; Si, Meiju; Cui, Lei; Zhu, Mankang; Yan, Hui

    2013-01-01

    In this work, two perovskite-type compounds, K 0.5 Bi 0.5 TiO 3 and LaAlO 3 , have been selected as host material to incorporate with BiAlO 3 using a solid-state reaction route. The phase evolution and dielectric properties for both systems have been investigated in detail. For the K 0.5 Bi 0.5 TiO 3 -BiAlO 3 system, it is interesting to find that when using Bi 2 O 3 , Al 2 O 3 , K 2 CO 3 , and TiO 2 as starting materials, the formed compounds are K 0.5 Bi 0.5 TiO 3 -K 0.5 Bi 4.5 Ti 4 O 15 and Al 2 O 3 only plays a dopant role. There are two distinct dielectric peaks appearing in the patterns of temperature dependence of dielectric constant, corresponding to the phase-transition points of perovskite-type K 0.5 Bi 0.5 TiO 3 and Aurivillius-type K 0.5 Bi 4.5 Ti 4 O 15 , independently. In comparison, using Bi 2 O 3 , Al 2 O 3 , and La 2 O 3 as starting materials, the pure perovskite phase LaAlO 3 -BiAlO 3 can be obtained. Compared to the inherent paraelectric behavior in LaAlO 3 , the diffuse phase-transition phenomena can be observed in the LaAlO 3 -BiAlO 3 binary system, which corresponds well to the Vogel-Fulcher (VF) relationship. Moreover, compared to pure LaAlO 3 , the synthesized LaAlO 3 -BiAlO 3 compound shows enhanced dielectric properties, which are promising in application as gate dielectric materials. (copyright 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  5. Improvement of High-Temperature Stability of Al2O3/Pt/ZnO/Al2O3 Film Electrode for SAW Devices by Using Al2O3 Barrier Layer

    Directory of Open Access Journals (Sweden)

    Xingpeng Liu

    2017-12-01

    Full Text Available In order to develop film electrodes for the surface acoustic wave (SAW devices operating in harsh high-temperature environments, novel Al2O3/Pt/ZnO/Al2O3 multilayered film electrodes were prepared by laser molecular beam epitaxy (LMBE at 150 °C. The first Al2O3 layer was used as a barrier layer to prevent the diffusion of Ga, La, and Si atoms from the La3Ga5SiO14 (LGS substrate to the film electrode and thus improved the crystalline quality of ZnO and Pt films. It was found that the resistance of the Al2O3/Pt/ZnO/Al2O3 electrode did not vary up to a temperature of 1150 °C, suggesting a high reliability of electrode under harsh high-temperature environments. The mechanism of the stable resistance of the Al2O3/Pt/ZnO/Al2O3 film electrodes at high temperature was investigated by analyzing its microstructure. The proposed Al2O3/Pt/ZnO/Al2O3 film electrode has great potential for application in high-temperature SAW devices.

  6. A note on Wang et al's attack on Zhang et al's multiparty quantum secret sharing

    International Nuclear Information System (INIS)

    Gao Gan

    2012-01-01

    Recently, Wang et al (2008 Phys. Lett. A 373 65) proposed an attack on Zhang et al's (2007 Opt. Commun. 269 418) multiparty quantum secret sharing scheme, in which the first and the last agent are reported to be able to cooperatively eavesdrop on all the secret messages without being detected. In this paper, we show that in Wang et al's attack, on average no more than half the secret messages can be eavesdropped. (paper)

  7. Comparison of energy expenditure and closed-loop performance of thermal and reactive distillation sequences coupled for biodiesel production; Comparacion de gasto energetico y desempeno a lazo cerrado de secuencias de destilacion reactiva y termicamente acopladas para produccion de biodiesel

    Energy Technology Data Exchange (ETDEWEB)

    Cornejo-Jacob, J.L [Universidad Michoacana de San Nicolas de Hidalgo, Morelia, Michoacan (Mexico); Vazquez-Ojeda, M; Segovia-Hernandez, J.G; Hernandez, S [Universidad de Guanajuato, Guanajuato, Guanajuato (Mexico); Maya-Yescas, R. [Universidad Michoacana de San Nicolas de Hidalgo, Morelia, Michoacan (Mexico)]. E-mail: rmayay@umich.mx

    2013-03-15

    Biodiesel is the common name for fatty acid methyl esters, obtained by esterification (basic catalysis) or trans-esterification (acid catalysis) of vegetable or animal oils with alcohols, and used as liquid fuel. Production involves the reaction, under mild conditions, between the oil and, typically, excess of methanol. Traditional production of biodiesel exhibits some handicaps, such as the shift of equilibrium to fatty acids by using excess of alcohol that must be separated and recycled. As alternative, it is possible to integrate reaction/separation operations into a single intensified unit, a reactive distillation column, followed by a second separation unit. These configurations exhibit several advantages such as shifting equilibrium in the reactive region and, because of the thermal integration with the second unit, energy savings during products separation. In order to design these production sequences taking advantage of steady state knowledge (energy savings) and considering dynamic performance, this work performs a controllability analysis for six possible configurations; open-loop control properties, evaluated by single value decomposition, are probed by implementing PI controllers to the system. The reactive distillation column coupled to a stripper, without reboilers, shows to be the best option in terms of closed-loop performance and energy savings. [Spanish] Biodiesel es el nombre comun dado a metil esteres de acidos grasos obtenidos por esterificacion (catalisis basica) o trans-esterificacion (catalisis acida) de aceites animales o vegetales con alcoholes, y usados como combustibles liquidos. Su produccion involucra la reaccion entre el aceite y, tipicamente, exceso de metanol a condiciones moderadas. La produccion tradicional de biodiesel exhibe algunas desventajas como el desplazamiento del equilibrio hacia acidos grasos debido al exceso de alcohol, que debe ser separado y reciclado. Alternativamente, es posible integrar las operaciones reaccion

  8. Regeneracion adventicia de somaclones de uchuva (Physalis peruviana

    Directory of Open Access Journals (Sweden)

    Santana Gloria E.

    1997-06-01

    Full Text Available

    Hipocoti1os de uchuva (Physalis peruvjana L. fueron utilizados en la inducción de callos y regeneración de plántulas. El medio basal de Murashige y Skoog (MS fue suplementado con bencil amino purina (BAP de 0 a 5,0 ppm, acido giberelico (GA3 0 Y 1,0 ppm en combinacion con acido naftalenoacetico (ANA de 0 a 1.0 ppm o con acido 2,4 diclorofenoxiacetico (2,4-D  de 0 a 1.0 ppm. La inducción de callos dependió de las interacciones hormonales y condiciones de luz. La regeneración de plántulas en medias que contenían ANA o cuando el medio no fue suplementado  con 2,4-D fue nula o muy poca. EI mayor numero de plántulas regeneradas fue observado en medios complementados con 1.0 ppm de BAP, 1,0 ppm de GA y 0,5 ppm de 2,4-D en condiciones de luz. Las plántulas regeneradas fueron micropropagadas en el medio basal de MS sin ningún suplemento hormonal. Finalmente, las plantas se evaluaron in vitro bajo condiciones de heladas simuladas.

    Palabras claves: Variaci6n somaclonal, inducción de callos morfogénesis indirecta, cultivo in vitro.

  9. Surface modified Al2O3 in fluorinated polyimide/Al2O3 ...

    Indian Academy of Sciences (India)

    guest group into a host structure without a major struc- tural modification of the ... on nano-structure size (Li et al 2009). Among ... naocomposite by the decrease of interfacial areas between ... pling agent which usually has a long alkyl tail shows a good ... the mechanical and thermal properties of polymers (Li et al. 2010).

  10. Microstructural defects modeling in the Al-Mo system

    International Nuclear Information System (INIS)

    Pascuet, Maria I.; Fernandez, Julian R.; Monti, Ana M.

    2006-01-01

    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 AlMo 3 intermetallic. Formation of vacancies for both components Al and Mo and anti-sites, Al Mo and Mo Al , 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 Al Mo +Mo Al , 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)/Al 5 Mo interface is stable, as observed experimentally. (author) [es

  11. Study of polarization curves from AlSi12, AlSi5Mg and AlMg5 alloys due to corrosion problems in telecomunication equipment

    International Nuclear Information System (INIS)

    Silva, J.R.A. da

    1984-01-01

    The corrosion behaviour of three aluminium based alloys (AlSi 12, AlMg5 and AlSi 5Mg) when exposed to aqueous media containing chloride is investigated; these alloys are used in the manufacturing of telecomunication equipment. Accelerated corrosion testing and salt spray tests were carried out. The results include polarization curves obtained with three kinds of aqueous solutions (the first containing only 3% NaCl and the others, 3% NaCl and small amounts of Fe 3+ and Cu 2+ ions). (C.L.B.) [pt

  12. The Calculation of Fe-Al-O Interaction Coefficient

    International Nuclear Information System (INIS)

    Kuo, Chin-Guo

    2010-01-01

    Aluminum is a very common deoxidizer in steel-making processes. The solubility of oxygen in molten iron decreases with increasing aluminum content. For the deoxidation process, the solubility of oxygen in Fe-Al melts decreases with increasing aluminum content. When %Al is increased to 0.34 wt.%, %O decreases to 6.4 ppm, which is the lowest point of the FeAl 2 O 4 curve. Then the Al 2 O 3 curve appears and replaces the FeAl 2 O 4 curve, where the interconnection point of the two curves is the coexistence point of FeAl 2 O 4 and Al 2 O 3 phases. When %Al is increased to 0.4%, the %O decreases to 6.35 ppm, which is the lowest point of the Al 2 O 3 curve. The solubility of oxygen in Fe-Al alloys is about 6.35 ppm with 0.4 wt.% aluminum at 1873 K. Liquid FeO-Al 2 O 3 , hercynite (FeAl 2 O 4 ), and alumina (Al 2 O 3 ) are three possible products during the deoxidation process. Based on thermodynamic calculation, the value of the interaction coefficient of e o Al was determined as -0.75 at 1873 K. This value is in good agreement with experimental curves in the literature.

  13. Annex 5 - Fabrication of U-Al alloy; Prilog 5 - Dobijanje legure U-Al

    Energy Technology Data Exchange (ETDEWEB)

    Drobnjak, Dj; Lazarevic, Dj; Mihajlovic, A [Institute of Nuclear Sciences Boris Kidric, Vinca, Beograd (Serbia and Montenegro)

    1961-12-15

    Alloy U-Al with low content of aluminium is often used for fabrication of fuel elements because it is stable under moderate neutron flux density. Additionally this type of alloys show much better characteristics than pure uranium under reactor operating conditions (temperature, mechanical load, corrosion effect of water). This report contains the analysis of the phase diagram of U-Al alloy with low content of aluminium, applied procedure for alloying and casting with detailed description of equipment. Characteristics of the obtained alloy are described and conclusions about the experiment and procedure are presented. Sistem U-Al sa niskim sadrzajem aluminijuma jedan je od cesto koriscenih za izradu gorivnih elemenata, jer je dovoljno stabilan pri umerenim gustinama fluksa. Pored toga, u uslovima karakteristicnim za rad nuklearnog reaktora (temperatura, gradijent temperature, mehanicka naprezanja, koroziono dejstvo vode) legure ovog sistema pokazuju daleko bolja svojstva od nelegiranog urana. Referat sadrzi analizu dijagrama stanja U-Al legure sa niskim sadrzajem aluminijuma, primenjeni postupak legiranja i livenja sa opisom pojedinih uredjaja i operacija. Takodje su opisana svojstva dobijene legure i dat je zakljucak o eksperimentu i tehnici rada (author)

  14. Structural properties of MBE AlInN and AlGaInN barrier layers for GaN-HEMT structures

    International Nuclear Information System (INIS)

    Kirste, Lutz; Lim, Taek; Aidam, Rolf; Mueller, Stefan; Waltereit, Patrick; Ambacher, Oliver

    2010-01-01

    A high-resolution X-ray diffraction and X-ray reflectivity study of the structural properties of AlInN/GaN and AlGaInN/GaN high electron mobility transistor structures deposited by molecular beam epitaxy on metal organic chemical vapor deposition GaN/Al 2 O 3 and GaN/SiC templates is presented. A new AlN/GaN/AlN triple-interlayer is implemented to improve the interface properties between barrier layer and GaN buffer for a higher mobility of the polarization induced two-dimensional electron gas. Layer properties and structural parameters like concentration, interface quality, layer thickness, strain and crystalline perfection are analyzed. Best structural properties are achieved for an AlGaInN layer with AlN/GaN/AlN interlayer deposited on a GaN/4H-SiC (00.1) template. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  15. Epidemiological trends of cutaneous leishmaniasis in Al-Madinah Al-Munawarah Province, Western Region of Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Miskelyemen Abdelatti Elmekki

    2017-01-01

    Full Text Available Objective: To investigate the epidemiological trends of cutaneous leishmaniasis (CL in Al-Madinah Al-Munawarah, western region of KSA. Materials and Methods: Four hundred and sixty-seven parasitologically confirmed CL cases attending Al-Meeqat Hospital, Al-Madinah, during 2012–2015, were included in this study. Results: Both Saudi and non-Saudi nationals were infected, with the highest infection rate being among Saudis (68.7%. Males were more affected than females as 86.9% of the total CL cases were males. Moreover, CL was prevalent in all age groups with higher frequency among young adults and adolescents (23.1% and 22.7%, respectively. Interestingly, almost all the patients in the adolescent and child age groups were Saudis (96.2% and 93.5%, respectively. Considering geographical distribution, the highest percentage of the cases (40.5% were from the northern parts of Al-Madinah province while the eastern parts reported the least infection rate (7.3%. Few cases (2.5% were supposed to encounter the infection abroad. Additionally, the frequency of infection was found to follow a seasonal distribution. Regarding treatment, pentostam, ketoconazole, or cryotherapy were the treatment options usually used. Conclusion: CL is prevalent in Al-Madinah Al-Munawarah area and new foci are being introduced. Thus, detailed studies with large surveillances regarding vector and reservoir hosts in and around the area are needed.

  16. The Effectiveness of Al-Si Coatings for Preventing Interfacial Reaction in Al-Mg Dissimilar Metal Welding

    Science.gov (United States)

    Wang, Yin; Al-Zubaidy, Basem; Prangnell, Philip B.

    2018-01-01

    The dissimilar welding of aluminum to magnesium is challenging because of the rapid formation of brittle intermetallic compounds (IMC) at the weld interface. An Al-Si coating interlayer was selected to address this problem, based on thermodynamic calculations which predicted that silicon would change the reaction path to avoid formation of the normally observed binary Al-Mg IMC phases ( β-Al3Mg2 and γ-Al12Mg17). Long-term static heat treatments confirmed that a Si-rich coating will preferentially produce the Mg2Si phase in competition with the less stable, β-Al3Mg2 and γ-Al12Mg17 binary IMC phases, and this reduced the overall reaction layer thickness. However, when an Al-Si clad sheet was tested in a real welding scenario, using the Refill™ friction stir spot welding (FSSW) technique, Mg2Si was only produced in very small amounts owing to the much shorter reaction time. Surprisingly, the coating still led to a significant reduction in the IMC reaction layer thickness and the welds exhibited enhanced mechanical performance, with improved strength and fracture energy. This beneficial behavior has been attributed to the softer coating material both reducing the welding temperature and giving rise to the incorporation of Si particles into the reaction layer, which toughened the brittle interfacial IMC phases during crack propagation.

  17. The core structures of transformation dislocations at TiAl/Ti3Al interfaces

    International Nuclear Information System (INIS)

    Penisson, J.M.; Loubradou, M.; Derder, C.; Bonnet, R.

    1993-01-01

    A Ti-40%Al alloy is investigated using High Resolution Electron Microscopy. The alloy structure consists mainly of alternate lamellae of γ(TiAl, L1 0 structure) and α 2 (Ti 3 Al, DO 19 structure) phases. These lamellae are parallel to each other and the interfaces between them are flat and parallel to the densest planes of the crystals. It is found that, among the variety of interfacial dislocations relieving the misfit, some have cores involving four (111) planes in height. The elastic displacement fields around these interfacial ledges, compared with the experimental atomic positions determined from HREM images, are in agreement with Burgers vector contents 1/6 left angle 112 right angle . (orig.)

  18. An independent assessment of Groeneveld et al.'s 1995 CHF look-up table

    International Nuclear Information System (INIS)

    Baek, W.-P.; Kim, H.-C.; Heung Chang, S.

    1997-01-01

    The prediction capability of the 1995 CHF look-up table (Groeneveld D.C., et al., Nucl. Eng. Des. 163 (1996) 1-23) is independently assessed based on the KAIST data base consisting of 10822 data for uniformly-heated, vertical, round tubes. This confirms the error statistics for the heat balance method reported by Groeneveld et al. and shows overall average and RMS errors of 4.2 and 36.7%, respectively, for the direct substitution method. The new 1995 table shows better prediction capability than the 1986 AECL-UO table (Groeneveld et al., 1986), especially for the low-pressure, low-flow region. The error analysis indicates the length effect even for significantly long tubes. (orig.)

  19. Atomistic calculations of hydrogen interactions with Ni3Al grain boundaries and Ni/Ni3Al interfaces

    International Nuclear Information System (INIS)

    Baskes, M.I.; Angelo, J.E.; Moody, N.R.

    1995-01-01

    Embedded Atom Method (EAM) potentials have been developed for the Ni/Al/H system. The potentials have been fit to numerous properties of this system. For example, these potentials represent the structural and elastic properties of bulk Ni, Al, Ni 3 Al, and NiAl quite well. In addition the potentials describe the solution and migration behavior of hydrogen in both nickel and aluminum. A number of calculations using these potentials have been performed. It is found that hydrogen strongly prefers sites in Ni 3 Al that are surrounded by 6 Ni atoms. Calculations of the trapping of hydrogen to a number of grain boundaries in Ni 3 Al have been performed as a function of hydrogen chemical potential at room temperature. The failure of these bicrystals under tensile stress has been examined and will be compared to the failure of pure Ni 3 Al boundaries. Boundaries containing a preponderance of nickel are severely weakened by hydrogen. In order to investigate the potential embrittlement of γ/γ' alloys, trapping of hydrogen to a spherical Ni 3 Al precipate in nickel as a function of chemical potential at room temperature has been calculated. It appears that the boundary is not a strong trap for hydrogen, hence embrittlement in these alloys is not primarily due to interactions of hydrogen with the γ/γ interface

  20. PHASE CONSTITUENTS AND MICROSTRUCTURE OF Ti3Al/Fe3Al + TiN/TiB2 COMPOSITE COATING ON TITANIUM ALLOY

    OpenAIRE

    JIANING LI; CHUANZHONG CHEN; CUIFANG ZHANG

    2011-01-01

    Laser cladding of the Fe3Al + B4C/TiN + Al2O3 pre-placed powders on the Ti-6Al-4V alloy can form the Ti3Al/Fe3Al + TiN/TiB2 composite coating, which improved the wear resistance of the Ti-6Al-4V alloy surface. In this study, the Ti3Al/Fe3Al + TiN/TiB2 composite coating has been researched by means of X-ray diffraction and scanning electron microscope. It was found that during the laser cladding process, Al2O3 can react with TiB2, leading to the formations of Ti3Al and B. This principle can be...

  1. Thermodynamic assessment of the Al-Ru system

    CSIR Research Space (South Africa)

    Prins, SN

    2003-03-01

    Full Text Available describes the order disorder transformation with one Gibbs energy function. The RuAl6 phase was described as a stoichiometric phase and the remaining intermetallic phases (Ru4Al13, RuAl2 and Ru2Al3) were modelled with the sublattice model. The solubility...

  2. Surgery for Gynecomastia in the Islamic Golden Age: Al-Tasrif of Al-Zahrawi (936–1013 AD)

    Science.gov (United States)

    Chavoushi, Seyed Hadi; Ghabili, Kamyar; Kazemi, Abdolhassan; Aslanabadi, Arash; Babapour, Sarah; Ahmedli, Rafail; Golzari, Samad E. J.

    2012-01-01

    The rise of European science during the Renaissance is greatly indebted to the flourishing of the sciences during the Islamic Golden Age. However, some believe that medieval Islamic physicians and in particular surgeons had been merely a medium for Greco-Roman ideas. Contrarily, in some medieval Islamic medical books, such as Al-Tasrif of Al-Zahrawi (936–1013), the surgical instructions represent a change in the usual techniques or are accompanied by a case history, implying that the procedure was actually undertaken. Along with the hundreds of chapters on different diseases and related medical and surgical treatments, Al-Tasrif includes a chapter on surgical techniques for gynecomastia. The present paper is a review of the description of the surgical management of gynecomastia by Al-Zahrawi as well as that of the ancient Greek, medieval, and modern medicine. Although Al-Zahrawi seemed to base his descriptions of surgery for gynecomastia upon those of Paulus of Aegina, his modification of the procedure and application of the medicinal substances might be indicative of Al-Zahrawi's own practice of the procedure. Al-Zahrawi's surgical procedures remained unchanged for many centuries thenceforward until the technological evolution in the recent centuries. PMID:23050167

  3. Corrosion and Discharge Behaviors of Mg-Al-Zn and Mg-Al-Zn-In Alloys as Anode Materials

    Directory of Open Access Journals (Sweden)

    Jiarun Li

    2016-03-01

    Full Text Available The Mg-6%Al-3%Zn and Mg-6%Al-3%Zn-(1%, 1.5%, 2%In alloys were prepared by melting and casting. Their microstructures were investigated via metallographic and energy-dispersive X-ray spectroscopy (EDS analysis. Moreover, hydrogen evolution and electrochemical tests were carried out in 3.5 wt% NaCl solution aiming at identifying their corrosion mechanisms and discharge behaviors. The results suggested that indium exerts an improvement on both the corrosion rate and the discharge activity of Mg-Al-Zn alloy via the effects of grain refining, β-Mg17Al12 precipitation, dissolving-reprecipitation, and self-peeling. The Mg-6%Al-3%Zn-1.5%In alloy with the highest corrosion rate at free corrosion potential did not perform desirable discharge activity indicating that the barrier effect caused by the β-Mg17Al12 phase would have been enhanced under the conditions of anodic polarization. The Mg-6%Al-3%Zn-1.0%In alloy with a relative low corrosion rate and a high discharge activity is a promising anode material for both cathodic protection and chemical power source applications.

  4. Al-muammar et al., Afr J Tradit Complement Altern Med. (2016) 13(1 ...

    African Journals Online (AJOL)

    PROF ADEWUNMI

    Al-muammar et al., Afr J Tradit Complement Altern Med. (2016) 13(1):17- .... Feed and water were provided ad libitum for one week before the start of experiment for adaptation. The basal .... The mean value of feed intake (g/day/rat) for all treated groups was slightly reduced as compared to the negative control group. On the.

  5. Al 3+ - Ca2+ INTERACTION IN PLANTS GROWING IN ACID SOILS: AL-PHYTOTOXICITY RESPONSE TO CALCAREOUS AMENDMENTS

    OpenAIRE

    Meriño-Gergichevich, C; Alberdi, M; Ivanov, A.G; Reyes-Diaz, M

    2010-01-01

    High aluminum (Al) concentrations as Al3+ represent an important growth and yield limiting factor for crops in acid soils (pH ≤5.5). The most recognized effect of Al-toxicity in plants is observed in roots. However, damages in the upper parts (including stem, leaves and fruits) may also be present. In addition, Al-toxicity triggers an increase in reactive oxygen species (ROS), causing oxidative stress that can damage the roots and chloroplasts, decreasing normal functioning of photo synthetic...

  6. Weldability of Al4C3-Al composites via diffusion welding technique

    International Nuclear Information System (INIS)

    Arik, Halil; Aydin, Mustafa; Kurt, Adem; Turker, Mehmet

    2005-01-01

    In this study, Al-Al 4 C 3 composites, produced by powder metallurgy in situ techniques, were joined by diffusion welding technique at 250 MPa pressure with various welding temperatures and durations. Microstructures and shear strengths of the joined areas were determined. Al powders were mixed with 2% carbon black and milled in a high energy ball mill (mechanical alloying) for up to 20 h. In order to obtain cylindrical blanks with 10 mm in diameter and 15 mm in height, powders were compacted in a single action press at 1000 MPa. Samples were sintered in Ar atmosphere at 650 deg C and metal matrix composite (MMC) containing 8% Al 4 C 3 particles were produced. Products were then joined to each other by using diffusion welding techniques. Scanning electron microscopy examination was carried out on the welded interfaces and shear tests were conducted to the sample interfaces to find out the effect of welding temperatures and duration on the weldability properties. It was found that high welding temperatures resulted in increase of both joined strength and shear properties. However, increase in welding duration did not make any detectable changes. Results indicated that MMC could be joined by diffusion welding technique successfully with the 88% strength of base material

  7. Basta de perseguir al pensamiento disidente: ¡Libertad al profesor Francisco Toloza!

    Directory of Open Access Journals (Sweden)

    Néstor Kohan

    2013-07-01

    Full Text Available Todo el tiempo encarcelan a nuestros compañeros. Buscan cansarnos y desgastarnos.  No  hay  mes  que  no  haya  que escribir  solidarizándose con algún revolucionario que acaban de encarcelar. ¿A esto llaman “libertad”? ¿A esto denominan “pluralismo”? ¿Esto es “el mundo libre”? ¡Por favor! Largan a uno y al día siguiente hay otro encarcelado. Acaban de soltar al cantante y compositor Julián Conrado y al mismo tiempo encarcelan al profesor Francisco Toloza. Nos mantienen “ocupados” pidiendo y reclamando todo el tiempo “suelten a fulano”, “liberen a mengano”. En Colombia. También en Argentina. En Paraguay. En todo el continente. No acabamos de ir a ver a un dirigente piquetero a la cárcel que ya hay otro campesino que está preso. No terminan de soltar a un cantante popular que ya metieron tras las rejas a un conocido profesor universitario. Y en ese vaivén se nos va la vida. Visitando presos, escribiendo todo el tiempo estas cartas de solidaridad, tratando de frenar la represión, la persecución, la demonización. ¿Hasta cuándo?

  8. Optimization of the boron content in FeAl (40 at. % Al) alloys

    International Nuclear Information System (INIS)

    Webb, G.; Juliet, P.; Lefort, A.

    1993-01-01

    FeAl intermetallic alloys are of interest for several high temperature applications due to excellent oxidation resistance, low density, and relatively low cost. Attempts to further increase the ductility of iron-rich FeAl have met with, at best, marginal success. Of the ductilization techniques employed, B doping appears to be a promising method for obtaining enhanced ductility and high strength in iron rich FeAl. Boron additions enhance the ductility of these alloys by increasing the grain boundary cohesive strength which reduces the tendency for intergranular fracture. The goal of the present work was to determine the optimum B concentration for increasing ambient temperature ductility. To accomplish this, a series of three iron rich FeAl alloys of similar Fe stoichiometries were doped with different levels of B (0,12, and 80 wppm). Secondary ion mass spectrometry (SIMS) was conducted on these alloys for evaluation of the B partitioning after consolidation by extrusion. Ambient temperature tensile testing and SEM fractography were then used to evaluate the effect of such additions on ambient temperature ductility in air. The results of these experiments indicate that optimum ductility is obtained from a homogeneous distribution of boron in which boride precipitation is limited

  9. Synthesis, microstructure and mechanical properties of (Ti1−x,Nbx)2AlC/Al2O3 solid solution composites

    International Nuclear Information System (INIS)

    Zhu, Jianfeng; Han, Na; Wang, Anning

    2012-01-01

    (Ti,Nb) 2 AlC/Al 2 O 3 in-situ solid solution composites were successfully synthesized from the elemental powder mixtures of Nb 2 O 5 , Ti, Al and carbon black using hot-press-aided reaction synthesis. The reaction path was investigated by differential scanning calorimetry (DSC) and X-ray diffractometry (XRD), and a possible reaction mechanism was proposed to explain the formation of (Ti,Nb) 2 AlC/Al 2 O 3 composites in which the thermite reaction between Al and Nb 2 O 5 formed Al 2 O 3 and Nb, and the latter together with TiAl and TiC reacted to form (Ti,Nb) 2 AlC. The synthesized composites show plate-like grains packed in a laminated structure typical of Ti 2 AlC, and the fine Al 2 O 3 particles formed in-situ tend to disperse on the matrix grain boundaries. Compared with the monolithic Ti 2 AlC synthesized using an identical process, the Vickers hardness, maximum compressive stress, flexural strength and fracture toughness of (Ti 0.96 ,Nb 0.04 ) 2 AlC/5 wt% Al 2 O 3 were enhanced by 33.8%, 12.1%, 118.4% and 111.8%, respectively. The mechanisms by which Al 2 O 3 increases the strength and toughness of the material were also discussed.

  10. Surface and interface analysis of PVD Al-O-N and {gamma}-Al{sub 2}O{sub 3} diffusion barriers

    Energy Technology Data Exchange (ETDEWEB)

    Cremer, R.; Witthaut, M.; Reichert, K.; Neuschuetz, D. [Technische Hochschule Aachen (Germany). Lehrstuhl fuer Metallurgie der Kernbrennstoffe und Theoretische Huettenkunde

    1999-10-01

    The suitability of PVD films of {gamma}-Al{sub 2}O{sub 3} and of ternary Al-O-N as diffusion barriers between a nickel based superalloy CMSX-4 and NiCoCrAlY for a possible application in gas turbines was investigated. Therefore, an Al{sub 2}O{sub 3} film and, alternatively, an Al-O-N film were deposited on CMSX-4 at 100 C substrate temperature by means of reactive magnetron sputtering ion plating (MSIP). After characterization of composition and structure of the films by X-ray photoelectron spectroscopy (XPS) and grazing incidence X-ray diffraction (XRD), a NiCoCrAlY coating was deposited onto the diffusion barriers and, for comparison, directly onto CMSX-4 by MSIP as well. The composites were annealed for 4 h at 1100 C under inert atmosphere. Wavelength dispersive X-ray (WDX) element mappings and line-scans of the cross-sectional cut served to evaluate the suitability of the films as diffusion barriers. After detachment of the coatings from the substrate, the phase stabilities of the two metastable phases {gamma}-Al{sub 2}O{sub 3} and Al-O-N were determined by means of grazing incidence XRD. Without a diffusion barrier, enhanced interdiffusion was observed. Analyses of the composite with the {gamma}-Al{sub 2}O{sub 3} interlayer revealed diffusion of Ti and Ta from the substrate into the NiCoCrAlY coating. No interdiffusion of Ni, Ti, Ta, and Cr could be detected in case of the ternary Al-O-N film. Whereas the ternary Al-O-N film remained in the as-deposited X-ray amorphous structure after annealing, a phase change from the {gamma} to the {alpha} modification could be observed in case of the Al{sub 2}O{sub 3} film, presumably responsible for its lower efficiency as a diffusion barrier. (orig.)

  11. The Effect of Mg Addition and Manufacturing Conditions on the Interfacial Reactions between Al and CNT in Al-CNT Pellets

    International Nuclear Information System (INIS)

    Lim, Jung-Kyu; Choi, Soon-Yool; Choe, Kyong-Hwan; Cho, Gue-Serb; Kim, Sang-Sub

    2013-01-01

    In the present study, Al-CNT pellets were investigated to understand the effect of Mg addition and manufacturing conditions on the interfacial reactions between Al and CNTs in Al-CNT pellets. The pellets were heated and held at 700 °C and 800 °C for 2 hours under nitrogen (N_2) atmosphere. To confirm the reactions between Al and CNT in the pellets under different manufacturing conditions, the microstructures were observed by optical microscopy (OM) and field emission scanning electro microscopy (FESEM). And, the composition and reaction phases were analyzed by energy dispersive X-ray spectroscory (EDXS) and X-ray diffractometry (XRD). The presence of oxidation products and Mg on the surface of Al powder in the pellets appeared to prevent the formation of Al_4C_3. But, Al_4C_3 reaction products were increased due to the high temperature of 800 °C, which produced a high amount of reduced aluminium and increased the reaction areas between Al and CNT. The Al-CNT pellets compacted under air atmosphere prohibited the reaction between Al and CNT because of the high amount of oxidation products, such as MgO and MgAl_2O_4.

  12. Laser alloyed Al-Ni-Fe coatings

    CSIR Research Space (South Africa)

    Pityana, SL

    2008-10-01

    Full Text Available The aim of this work was to produce crack-free thin surface layers consisting of binary (Al-Ni, Al-Fe) and ternary (Al-Ni-Fe) intermetallic phases by means of a high power laser beam. The laser surface alloying was carried out by melting Fe and Ni...

  13. Computer aided cooling curve analysis for Al-5Si and Al-11Si alloys

    African Journals Online (AJOL)

    user

    fine fibrous form (Hess and Blackmun, 1975; Dahle et al., 2005). ..... grain structure in the casting (Apelian et al., 1984), which in turn are supported in the present work by a decreased ..... Liao H., Zhang M., Wu Q., Wang H. and Sun G., 2007.

  14. La «historia de los omeyas de al-Andalus» en los Masālik al-Abṣār

    Directory of Open Access Journals (Sweden)

    Molina, Luis

    2005-06-01

    Full Text Available The Māsilik al-abṣār by Ibn Faḍl Allāh al-'Umarī contains a brief summary of the Umayyad history in al-Andalus. In this article, the textual relationship between this passage and the Muqtabis by Ibn Ḥayyān is analysed. Ibn Ḥayyān's chronicle has proved to be the most important source used by al-'Umarī to compose this chapter.

    Los Māsilik al-abṣār de Ibn Faḍl Allāh al-'Umarī incluyen un breve resumen de la Historia de los omeyas de al-Andalus. En este trabajo se analizan las relaciones textuales entre ese pasaje y el Muqtabis de Ibn Ḥayyān, crónica que resulta ser la fuente casi única utilizada por al-'Umarī para redactar ese capítulo.

  15. High-temperature resistant MeCrAlY+Al coatings obtained by ARC-PVD method on Ni Base superalloys

    International Nuclear Information System (INIS)

    Swadzba, L.; Maciejny, A.; Mendala, B.; Supernak, W.

    1999-01-01

    Investigations of obtaining high temperature coatings on the Ni base superalloys by the ARC-PVD method, using exothermic reaction processes between Ni and Al with NiAl intermetallic formation are presented in the article. By the diffusion heating at 1050 o C NiAl high temperature diffusion coating containing 21% at. Al and 50 μm thick was obtained. In the next stage coatings with more complex chemical composition NiCoCrAlY were formed. The two targets were applied for formation of complex NiCoCrAlY coatings. The good consistence between the chemical composition of the targets and the coatings and an uniform distribution of elements in the coatings were shown. Then the surface was covered with aluminium also by the ARC-PVD method. In the vacuum chamber of the equipment a synthesis reaction between NiCoCrAlY and Al with the formation NiAl intermetallics of high Co, Cr, Y content was initiated by the changes in process parameters. The final heat treatment of coatings was conducted in the air and vacuum at 1050 o C. The strong segregation of yttrium in to the oxide scale in the specimens heated in the air was shown. It was possible to obtain NiAl intermetallic phase coatings modified by Co, Cr and Y by the ARC-PVD method. An example of the application of this method for the aircraft engine turbine blades was presented. Method of ARC-PVD gives the possibility chemical composition and high resistance to oxidizing and hot corrosion. (author)

  16. Als2 mRNA splicing variants detected in KO mice rescue severe motor dysfunction phenotype in Als2 knock-down zebrafish.

    Science.gov (United States)

    Gros-Louis, Francois; Kriz, Jasna; Kabashi, Edor; McDearmid, Jonathan; Millecamps, Stéphanie; Urushitani, Makoto; Lin, Li; Dion, Patrick; Zhu, Qinzhang; Drapeau, Pierre; Julien, Jean-Pierre; Rouleau, Guy A

    2008-09-01

    Recessive ALS2 mutations are linked to three related but slightly different neurodegenerative disorders: amyotrophic lateral sclerosis, hereditary spastic paraplegia and primary lateral sclerosis. To investigate the function of the ALS2 encoded protein, we generated Als2 knock-out (KO) mice and zAls2 knock-down zebrafish. The Als2(-/-) mice lacking exon 2 and part of exon 3 developed mild signs of neurodegeneration compatible with axonal transport deficiency. In contrast, zAls2 knock-down zebrafish had severe developmental abnormalities, swimming deficits and motor neuron perturbation. We identified, by RT-PCR, northern and western blotting novel Als2 transcripts in mouse central nervous system. These Als2 transcripts were present in Als2 null mice as well as in wild-type littermates and some rescued the zebrafish phenotype. Thus, we speculate that the newly identified Als2 mRNA species prevent the Als2 KO mice from developing severe neurodegenerative disease and might also regulate the severity of the motor neurons phenotype observed in ALS2 patients.

  17. Epitaxial growth of GaN/AlN/InAlN heterostructures for HEMTs in horizontal MOCVD reactors with different designs

    Energy Technology Data Exchange (ETDEWEB)

    Tsatsulnikov, A. F., E-mail: andrew@beam.ioffe.ru; Lundin, W. V.; Sakharov, A. V.; Zavarin, E. E.; Usov, S. O.; Nikolaev, A. E.; Yagovkina, M. A.; Ustinov, V. M. [Russian Academy of Sciences, Ioffe Physical–Technical Institute (Russian Federation); Cherkashin, N. A. [CEMES–CNRS—Université de Toulouse (France)

    2016-09-15

    The epitaxial growth of InAlN layers and GaN/AlN/InAlN heterostructures for HEMTs in growth systems with horizontal reactors of the sizes 1 × 2', 3 × 2', and 6 × 2' is investigated. Studies of the structural properties of the grown InAlN layers and electrophysical parameters of the GaN/AlN/InAlN heterostructures show that the optimal quality of epitaxial growth is attained upon a compromise between the growth conditions for InGaN and AlGaN. A comparison of the epitaxial growth in different reactors shows that optimal conditions are realized in small-scale reactors which make possible the suppression of parasitic reactions in the gas phase. In addition, the size of the reactor should be sufficient to provide highly homogeneous heterostructure parameters over area for the subsequent fabrication of devices. The optimal compositions and thicknesses of the InAlN layer for attaining the highest conductance in GaN/AlN/InAlN transistor heterostructures.

  18. Chemical and electrical characterisation of the segregation of Al from a CuAl alloy (90%:10% wt) with thermal anneal

    Energy Technology Data Exchange (ETDEWEB)

    Byrne, C., E-mail: conor.byrne2@mail.dcu.ie [School of Physical Sciences, Dublin City University, Dublin 9 (Ireland); Brady, A.; Walsh, L.; McCoy, A.P.; Bogan, J. [School of Physical Sciences, Dublin City University, Dublin 9 (Ireland); McGlynn, E. [School of Physical Sciences, National Centre for Plasma Science and Technology, Dublin City University, Dublin 9 (Ireland); Rajani, K.V. [School of Electronic Engineering, Dublin City University, Dublin 9 (Ireland); Hughes, G. [School of Physical Sciences, Dublin City University, Dublin 9 (Ireland); School of Physical Sciences, National Centre for Plasma Science and Technology, Dublin City University, Dublin 9 (Ireland)

    2016-01-29

    A copper–aluminium (CuAl) alloy (90%:10% wt) has been investigated in relation to segregation of the alloying element Al, from the alloy bulk during vacuum anneal treatments. X-ray photoelectron spectroscopy (XPS) measurements were used to track the surface enrichment of Al segregating from the alloy bulk during in situ ultra-high vacuum anneals. Secondary ion mass spectroscopy (SIMS) indicates a build-up of Al at the surface of the annealed alloy relative to the bulk composition. Metal oxide semiconductor (MOS) CuAl/SiO{sub 2}/Si structures show a shift in flatband voltage upon thermal anneal consistent with the segregation of the Al to the alloy/SiO{sub 2} interface. Electrical four point probe measurements indicate that the segregation of Al from the alloy bulk following thermal annealing results in a decrease in film resistivity. X-ray diffraction data shows evidence for significant changes in crystal structure upon annealing, providing further evidence for expulsion of Al from the alloy bulk. - Highlights: • CuAl alloy (90%:Al 10% wt) deposited and vacuum annealed • XPS and SIMS data show segregation of Al from the alloy bulk. • Chemical changes seen indicate the reduction of Cu oxide and growth of Al Oxide. • Electrical measurements indicate a chemical change at the metal/SiO{sub 2} interface. • All data consistent with Cu diffusion barrier layer formed.

  19. Heterotopia als sociaal-ruimtelijke constructie

    NARCIS (Netherlands)

    Lengkeek, J.

    2003-01-01

    Uitleg van het begrip heterotopia, waar het gaat om het gebruik van de ruimte. Volgens de auteur wordt heterotopia als persoonlijke ruimte en als vrijetijdsruimte op tal van manieren tot stand gebracht; het is een georganiseerde wereld

  20. Investigation on Mechanical Properties and Reaction Characteristics of Al-PTFE Composites with Different Al Particle Size

    Directory of Open Access Journals (Sweden)

    Jia-xiang Wu

    2018-01-01

    Full Text Available Al-PTFE (aluminum-polytetrafluoroethylene serves as one among the most promising reactive materials (RMs. In this work, six types of Al-PTFE composites with different Al particle sizes (i.e., 50 nm, 1∼2 μm, 6∼7 μm, 12∼14 μm, 22∼24 μm, and 32∼34 μm were prepared, and quasistatic compression and drop weight tests were conducted to characterize the mechanical properties and reaction characteristics of Al-PTFE composites. The reaction phenomenon and stress-strain curves were recorded by a high-speed camera and universal testing machine. The microstructure of selected specimens was anatomized through adopting a scanning electron microscope (SEM to correlate the mesoscale structural characteristics to their macroproperties. As the results indicated, in the case of quasistatic compression, the strength of the composites was decreased (the yield strength falling from 22.7 MPa to 13.6 MPa and the hardening modulus declining from 33.3 MPa to 25 MPa with the increase of the Al particle size. The toughness rose firstly and subsequently decreased and peaked as 116.42 MJ/m3 at 6∼7 μm. The reaction phenomenon occurred only in composites with the Al particle size less than 10 μm. In drop weight tests, six types of specimens were overall reacted. As the Al particle size rose, the ignition energy of the composites enhanced and the composites turned out to be more insensitive to reaction. In a lower strain rate range (10−2·s−1∼102·s−1, Al-PTFE specimens take on different mechanical properties and reaction characteristics in the case of different strain rates. The formation of circumferential open cracks is deemed as a prerequisite for Al-PTFE specimens to go through a reaction.

  1. Characterization of microstructure and mechanical properties of friction stir welded AlMg5- Al{sub 2}O{sub 3} nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Babu, N. Kishore, E-mail: kishorebabu.nagumothu@empa.ch [Empa, Swiss Federal Laboratories for Material Science and Technology, Laboratory for Advanced Materials Processing, Feuerwerkerstrasse 39, CH-3602 Thun (Switzerland); Kallip, Kaspar; Leparoux, Marc [Empa, Swiss Federal Laboratories for Material Science and Technology, Laboratory for Advanced Materials Processing, Feuerwerkerstrasse 39, CH-3602 Thun (Switzerland); AlOgab, Khaled A. [King Abdulaziz City for Science and Technology (KACST), National Centers for Advanced Materials, P O Box 6086, Riyadh, 11442 (Saudi Arabia); Reddy, G.M. [Defence Metallurical Research Laboratory, Hyderabad-500 058 (India); Talari, M.K. [Faculty of Applied Sciences, Universiti Teknologi MARA, 40450 Shah Alam (Malaysia)

    2016-03-21

    In the present study, powder metallurgy processed unmilled AlMg5, milled AlMg5 and milled AlMg5-0.5 vol% Al{sub 2}O{sub 3} nanocomposite have been successfully friction stir welded (FSW). The effect of friction stir welding on the evolution of weld microstructures; hardness and tensile properties were studied and discussed in detail. FSW of unmilled AlMg5 resulted in significant grain refinement and strain hardening in the nugget zone induced by the thermo-mechanical processing, thereby increasing the stir zone hardness and tensile strengths to 100 HV and 324 MPa when compared to 80 HV and 300 MPa of base metal, respectively. In contrast, the FSW of milled AlMg5 and milled AlMg5-0.5 vol% Al{sub 2}O{sub 3} samples showed a reduction in UTS values to 375 MPa and 401 MPa in the stir zone compared to 401 MPa and 483 MPa of respective base metal values. Transmission electron microscopic (TEM) investigation of weld stir zones revealed the homogenous distribution of Al{sub 4}C{sub 3} nanophases in milled AlMg5 and Al{sub 2}O{sub 3} nanoparticles in milled AlMg5-0.5 vol% Al{sub 2}O{sub 3} samples throughout the aluminium matrix. It was revealed that the pre-stored energy from the prior ball milling and hot pressing processes, higher deformation energy and grain boundary pinning effect due to the presence of reinforcement particles has resulted in a higher recrystallization tendency and retarded grain growth during FSW of milled samples. The welds prepared with milled AlMg5-0.5 vol% Al{sub 2}O{sub 3} exhibited higher hardness and tensile strength in the stir zone when compared to all other conditions which was attributed to Hall Petch effect due to fine grain size and Orowan strengthening effect due to Al{sub 2}O{sub 3} reinforcements.

  2. Addition of iron for the removal of the {beta}-AlFeSi intermetallic by refining of {alpha}-AlFeSi phase in an Al-7.5Si-3.6Cu alloy

    Energy Technology Data Exchange (ETDEWEB)

    Belmares-Perales, S. [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon (Mexico); Zaldivar-Cadena, A.A., E-mail: azaldiva70@hotmail.com [Facultad de Ingenieria Civil, Departamento de Ecomateriales y Energia, Instituto de Ingenieria Civil, Av. Fidel Velasquez and Av. Universidad S/N, Cd. Universitaria, San Nicolas de los Garza, N.L. 66450 (Mexico)

    2010-10-25

    Addition of iron into the molten metal for the removal of the {beta}-AlFeSi intermetallic by refining of {alpha}-AlFeSi phase has been studied. Solidification conditions and composition determine the final microstructure and mechanical properties of a casting piece. It is known that increasing the iron content will produce an increasing of the {alpha}-AlFeSi and {beta}-AlFeSi phases. This phenomenon was confirmed with calculations made by Thermo-Calc{sup TM} software and validated with experimental results, however, the technique of iron addition in this study plays an important role on the solidification kinetics of these iron phases because the refining of {alpha}-AlFeSi and removal of {beta}-AlFeSi phases can be improved. Final results showed an improvement in mechanical properties by removal and refining of {beta}-AlFeSi and {alpha}-AlFeSi phases, respectively. This study shows a new method of removal of {beta}-AlFeSi that could be adopted in the aluminum smelting industry in aluminum alloys with a low cooling rate with a secondary dendritic spacing of about 37 {mu}m.

  3. Addition of iron for the removal of the β-AlFeSi intermetallic by refining of α-AlFeSi phase in an Al-7.5Si-3.6Cu alloy

    International Nuclear Information System (INIS)

    Belmares-Perales, S.; Zaldivar-Cadena, A.A.

    2010-01-01

    Addition of iron into the molten metal for the removal of the β-AlFeSi intermetallic by refining of α-AlFeSi phase has been studied. Solidification conditions and composition determine the final microstructure and mechanical properties of a casting piece. It is known that increasing the iron content will produce an increasing of the α-AlFeSi and β-AlFeSi phases. This phenomenon was confirmed with calculations made by Thermo-Calc TM software and validated with experimental results, however, the technique of iron addition in this study plays an important role on the solidification kinetics of these iron phases because the refining of α-AlFeSi and removal of β-AlFeSi phases can be improved. Final results showed an improvement in mechanical properties by removal and refining of β-AlFeSi and α-AlFeSi phases, respectively. This study shows a new method of removal of β-AlFeSi that could be adopted in the aluminum smelting industry in aluminum alloys with a low cooling rate with a secondary dendritic spacing of about 37 μm.

  4. 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.

  5. Communication: The Al + CO2 → AlO + CO reaction: Experiment vs. theory

    Science.gov (United States)

    Sun, Zhi; Moore, Kevin B.; Schaefer, Henry F.

    2017-11-01

    Based on their highly sophisticated crossed-beam experimental studies of the Al + CO2 → AlO + CO reaction, Honma and Hirata have directly challenged the results of earlier theoretical studies of this system. We report high level theoretical studies of this system. It is shown that, consistent with Honma-Hirata experimental conclusions, the previous theoretical prediction of a substantial barrier height for this reaction was incorrect. However, for the structures of the possible intermediates, in agreement with the 1992 theoretical study of Sakai, we find striking disagreement with the experimental conclusion that the O-C-O moiety is nearly linear. The energies of the three entrance channel intermediates lie 14.4, 15.2, and 16.4 kcal mol-1 below separated Al + CO2.

  6. Effect of TiAl_3 on distribution of TiC particles in aluminum matrix and nucleation of α(Al) grain%TiAl_3对TiC粒子在铝基体中分布及α(Al)晶粒形核的影响

    Institute of Scientific and Technical Information of China (English)

    夏天东; 丁万武; 赵文军; 王晓军; 徐仰涛

    2009-01-01

    研究TiC和TiAl_3细化工业纯铝时TiAl_3的存在对TiC在铝基体中分布及α(Al)晶粒形核的影响,分析Al-Ti-C晶粒细化机制.结果表明:TiC单独作为工业纯铝的晶粒细化剂时,大量TiC被α(Al)晶粒推向树枝晶的晶界处,从而限制了TiC的异质形核作用;当TiC和TiAl_3共同作为晶粒细化剂时,在α(Al)晶粒内部出现了大量TiC粒子,大量的TiC粒子成为了α(Al)的结晶核心,并且在TiC颗粒和铝基体的界面处存在"富Ti过渡区";TiAl_3在铝熔体中分解释放出Ti原子并向TiC粒子周围偏聚,形成的"TiC/铝熔体界面富Ti过渡区" 改善了TiC与α(Al)的结构适应性,降低了TiC粒子的表面张力,促进了TiC粒子在铝熔体中的均匀分布,提高了其形核能力.%The effect of TiAl_3 on the distribution of TiC particles in aluminum matrix and nucleation of α(Al) grain was studied when the TiC and TiAl_3 refining industry aluminum, and the nucleation mechanism of Al-Ti-C grain refiner were discussed. The results show that when TiC alone is used as the nucleation phase, most of the TiC is pushed into the grain boundaries by the α(Al) dendrites and the nucleation of TiC is restricted. On the other hand, when TiC and TiAl_3 refine the industry aluminum together, most of the TiC particles are found within the α(Al) grains and nucleation occurs on TiC particles, and there is a Ti transition zone between TiC and aluminum interface. TiAl_3 releases Ti atoms in aluminum melt, Ti atoms congregate to the TiC surface, and ultimately forming TiC/aluminum interface Ti transition zone, which not only improves the structure of adaptability and wettability between TiC and Al , but also reduces the surface tension of TiC particles, which making a lot of TiC particles can be uniformly distributed in the aluminum melt, which advance α(Al) core and heterogeneous nucleation in the aluminum melt solidification.

  7. 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...... which is approximately 50 times greater than that of LiF:Mg,Ti is an interesting dosimetry material; however due to a high fading rate of the TL of AlN:Y2O3 on storage at room temperature, a further development of the material for improving the fading characteristics is needed for its application...

  8. Characterising μ-AlTiN coating and assessing its performance during Ti-6Al-4V milling

    Directory of Open Access Journals (Sweden)

    Carlos Mauricio Moreno Téllez

    2013-05-01

    Full Text Available This study investigated the mechanical properties and performance of μ-AlTiN coating deposited by PVD cathodic arc technique for a specific Al0, 67Ti0, 33N composition deposited on a WC-Co and AISI D2 steel substrate. The structure of the coating was analysed using SEM, EDAX, XRD, AFM and TEM. Nano indentation measurements were used for analysing mechanical properties; the coating’s performance was evaluated during the milling of a titanium alloy (Ti6Al4V. The TiN film was initially deposited to improve adhesion between coating and substrate, where columnar grains ranging in size from 200 to 500 nm were observed having NaCl-type struc-ture. μ-AlTiN grain growth was also columnar but had ~50 nm grain size. The μ-AlTiN coated tool life was compared to an uncoated tool to determine the coating’s influence during Ti6Al4V milling. The μ-AlTiN coating improved tool life by 100% compared to that of an uncoated tool due to aluminium oxide and TiC formation on the surface and a decrease in friction coefficient between the chip and the tool.

  9. Growth of C60 thin films on Al2O3/NiAl(100) at early stages

    Science.gov (United States)

    Hsu, S.-C.; Liao, C