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Sample records for ce em ferricretes

  1. Cério (Ce em ferricretes nodulares desenvolvidos em solos da formação adamantina Cerium (Ce in some nodular ferricretes developed in soils of the adamantina formation

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    Maurício Rizzato Coelho

    2000-06-01

    Full Text Available O estudo de concentrações anômalas de elementos traço em ferricretes, como cério (Ce e outros elementos das terras raras, tem apoiado discussões a respeito da gênese dessas feições em diferentes ambientes do planeta. No município de Pindorama (SP, no sopé de uma vertente com domínio de Argissolos Vermelho-Amarelos abrúpticos derivados do arenito cretácico da Formação Adamantina, Grupo Bauru (Ka, ocorrem horizontes ferricretes, cujas características e gênese são escassamente conhecidas, embora sejam de ocorrência comum na região norte do Estado de São Paulo. Procurou-se verificar a presença de concentrações de elementos terras raras nesses solos e assim poder fornecer subsídios para o conhecimento da gênese desses ferricretes, estudando-se um Argissolo Vermelho-Amarelo Eutrófico abrúptico plíntico dessa vertente. Após descrição morfológica do perfil, determinou-se a granulometria, bem como as concentrações de Fe e Mn totais (fluorescência de raios X, extraídos por ataque sulfúrico, ditionito-citrato e por oxalato dos horizontes e dos nódulos encontrados. Em glébulas selecionadas, realizou-se estudos submicroscópicos e microanálises pontuais. Acumulações localizadas de Ce na forma de cerianita (CeO2 foram encontradas apenas nos nódulos petroplínticos que apresentam revestimentos de óxidos de Mn, situados na base do horizonte petroplíntico, e cuja gênese está associada ao rebaixamento definitivo do lençol freático. Cobalto (Co também se concentra no interior dos nódulos ferro-manganíferos devido à ação co-precipitadora dos óxidos de manganês aí depositados.The observation of rare earth element (REE accumulations, especially Ce, has led to an open discussion about the genesis of lateritic weathering systems. In the landscape of the northern State of São Paulo (Brazil, lateritic covers predominantly nodular exist in different topographic levels and, although not documented, constitute a

  2. Macro e micromorfologia de ferricretes nodulares desenvolvidos de arenito do grupo Bauru, formação Adamantina

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    M. R. Coelho

    2001-06-01

    Full Text Available Nas paisagens do norte do estado de São Paulo, sob domínio do Planalto Ocidental, ferricretes ocorrem em diferentes níveis topográficos e, apesar de pouco documentados, constituem feições que se repetem com freqüência sobre os arenitos cretácicos do Grupo Bauru, Formação Adamantina. Realizou-se um estudo morfológico, em diferentes escalas de observação, a fim de elucidar a gênese desses ferricretes (plintita e petroplintita encontrados no terço inferior de uma vertente dominada por solos com B textural. A área estudada localiza-se na Estação Experimental de Agronomia de Pindorama, do Instituto Agronômico de Campinas (IAC, região norte do estado de São Paulo. Dois perfis foram selecionados para a descrição morfológica detalhada e para as observações micromorfológicas com lupa binocular e microscópio petrográfico. As evidências macro e micromorfológicas dos ferricretes revelam uma origem associada à lixiviação do ferro ferroso a montante da paisagem e reprecipitação na zona de vadosa. Esses ferricretes apresentaram diferentes fábricas internas, a maioria dos quais com estruturas de degradação, evidenciando o desmantelamento atual da couraça. As diferenças nas fábricas internas estão relacionadas com a distribuição do esqueleto e do plasma: alguns apresentam esqueleto bem selecionado, com predominância de areia muito fina, enquanto em outros predomina a areia média; outros, ainda, mostram esqueleto pouco selecionado, assemelhando-se ao fundo matricial interglebular; a maioria mostra alguns volumes ocupados apenas por plasma. Demonstra-se que fatores pedo-lito-biológicos estão envolvidos nessa diversidade entre ferricretes de um mesmo horizonte, formando in situ glébulas tão distintas em suas fábricas, que podem ser erroneamente interpretadas como provenientes de diferentes locais da paisagem, transportadas e depositadas nas baixas encostas durante a gênese dos ferricretes.

  3. Tecnologias educativas no contexto escolar: estratégia de educação em saúde em escola pública de Fortaleza-CE

    OpenAIRE

    Fabiane do Amaral Gubert; Ana Carolina Lobo dos Santos; Katiana Araújo Aragão; Dayse Christina Rodrigues Pereira; Neiva Francenely Cunha Vieira; Patricia Neyva da Costa Pinheiro

    2009-01-01

    O objetivo deste estudo é abordar o uso de tecnologias educativas como estratégia de educação em saúde junto aadolescentes no contexto escolar. A coleta de dados ocorreu entre abril e maio de 2007 em uma escola pública municipal nacidade de Fortaleza-CE, por meio de um ciclo de quatro oficinas educativas realizadas com 30 adolescentes. As oficinastiveram o intuito promover a reflexão/ação junto aos participantes sobre as temáticas: sexualidade, gênero, DST/AIDS emétodos contraceptivos. Estudo...

  4. Lattice dynamics and elastic properties of the 4<em>f> electron system: CeN

    DEFF Research Database (Denmark)

    Kanchana, V.; Vaitheeswaran, G.; Zhang, Xinxin;

    2011-01-01

    are hence allowed to hop from site to site, without an on-site Hubbard U, and contribute to the bonding, in a picture often referred to as itinerant. It is argued that this picture is appropriate for CeN at low temperatures, while the anomalous thermal expansion observed at elevated temperatures...... indicates entropy-driven localization of the Ce f electrons, similar to the behavior of elemental cerium. The elastic constants are predicted from the total energy variation of strained crystals and are found to be large, typical for nitrides. The phonon dispersions are calculated showing no soft modes, and...

  5. Prática docente em educação sexual em uma escola pública de Juazeiro do Norte, CE, Brasil

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    Glauberto da Silva Quirino

    2013-01-01

    Full Text Available Estudo etnográfico com base na observação participante e entrevista semiestruturada, que objetivou descrever o trabalho de educação sexual dos/as professores/as, e apreender os valores e as atitudes destes/as em relação à sexualidade de adolescentes no espaço escolar. O trabalho de campo foi desenvolvido em uma escola de Ensino Fundamental e Médio estadual da cidade de Juazeiro do Norte-CE, no período de setembro de 2009 a fevereiro de 2010. Constatou-se que, mesmo sendo o assunto suscitado por parte dos/as estudantes, sempre os/as professores/as se omitiram em realizar qualquer intervenção. Observou-se a presença de valores morais e pessoais na condução das práticas educativas, atitudes de silenciamento em relação ao preconceito a homossexuais e a perda da virgindade, assim como manutenção das desigualdades de gênero. Os dados apontam as fragilidades das ações pedagógicas e a necessidade de mudança de paradigma do processo ensino/aprendizagem.

  6. An empirical method for estimating instream pre-mining pH and dissolved Cu concentration in catchments with acidic drainage and ferricrete

    Science.gov (United States)

    Nimick, D.A.; Gurrieri, J.T.; Furniss, G.

    2009-01-01

    Methods for assessing natural background water quality of streams affected by historical mining are vigorously debated. An empirical method is proposed in which stream-specific estimation equations are generated from relationships between either pH or dissolved Cu concentration in stream water and the Fe/Cu concentration ratio in Fe-precipitates presently forming in the stream. The equations and Fe/Cu ratios for pre-mining deposits of alluvial ferricrete then were used to reconstruct estimated pre-mining longitudinal profiles for pH and dissolved Cu in three acidic streams in Montana, USA. Primary assumptions underlying the proposed method are that alluvial ferricretes and modern Fe-precipitates share a common origin, that the Cu content of Fe-precipitates remains constant during and after conversion to ferricrete, and that geochemical factors other than pH and dissolved Cu concentration play a lesser role in determining Fe/Cu ratios in Fe-precipitates. The method was evaluated by applying it in a fourth, naturally acidic stream unaffected by mining, where estimated pre-mining pH and Cu concentrations were similar to present-day values, and by demonstrating that inflows, particularly from unmined areas, had consistent effects on both the pre-mining and measured profiles of pH and Cu concentration. Using this method, it was estimated that mining has affected about 480 m of Daisy Creek, 1.8 km of Fisher Creek, and at least 1 km of Swift Gulch. Mean values of pH decreased by about 0.6 pH units to about 3.2 in Daisy Creek and by 1-1.5 pH units to about 3.5 in Fisher Creek. In Swift Gulch, mining appears to have decreased pH from about 5.5 to as low as 3.6. Dissolved Cu concentrations increased due to mining almost 40% in Daisy Creek to a mean of 11.7 mg/L and as much as 230% in Fisher Creek to 0.690 mg/L. Uncertainty in the fate of Cu during the conversion of Fe-precipitates to ferricrete translates to potential errors in pre-mining estimates of as much as 0.25 units

  7. Decay Time Optimization of YAG:Ce Scintillator for S(T)EM Electron Detector

    Czech Academy of Sciences Publication Activity Database

    Schauer, Petr

    Sapporo : Japanese Society of Microscopy , 2006, s. 655. [IMC16 - International Microscopy Congress /16./. Sapporo (JP), 03.09.2006-08.09.2006] R&D Projects: GA ČR GA102/04/2144 Institutional research plan: CEZ:AV0Z20650511 Keywords : scintillation detector * electron microscope * cathodoluminescence * YAG:Ce * single crystal scintillator * decay time * afterglow * kinetic model * SEM * STEM Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  8. Tecnologias educativas no contexto escolar: estratégia de educação em saúde em escola pública de Fortaleza-CE

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    Fabiane do Amaral Gubert

    2009-03-01

    Full Text Available O objetivo deste estudo é abordar o uso de tecnologias educativas como estratégia de educação em saúde junto aadolescentes no contexto escolar. A coleta de dados ocorreu entre abril e maio de 2007 em uma escola pública municipal nacidade de Fortaleza-CE, por meio de um ciclo de quatro oficinas educativas realizadas com 30 adolescentes. As oficinastiveram o intuito promover a reflexão/ação junto aos participantes sobre as temáticas: sexualidade, gênero, DST/AIDS emétodos contraceptivos. Estudo do tipo pesquisa-ação, de abordagem qualitativa, apoiado no Modelo Pedagógico de PauloFreire. Os resultados evidenciaram lacunas no conhecimento quanto às formas de infecção pelas DST e uso adequado demétodos contraceptivos. Outro dado refere-se às questões de gênero que parecem influenciar na qualidade de vida dosjovens do estudo. O uso de tecnologias educativas pôde despertar entre os adolescentes, um repensar sobre a vivência dasaúde sexual e reprodutiva a partir das vulnerabilidades percebidas. Recomendamos a partir dos achados, que as atividadesde prevenção às DST/AIDS no âmbito da escola, rompam com a visão heterossexista, normativa e biologicista. Nessecontexto, a Enfermeira deve produzir/readequar novas tecnologias educativas que favoreçam o processo educação em saúde,valorizando as habilidades e aspirações dos adolescentes.

  9. Enfrentamento da AIDS entre mulheres infectadas em Fortaleza - CE Enfrentamento del SIDA entre mujeres infectadas en Fortaleza-CE How infected women in Fortaleza-CE cope with AIDS

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    Carolina Maria de Lima Carvalho

    2008-03-01

    Full Text Available Este estudo objetivou apreender como as mulheres com aids enfrentam o cotidiano após o conhecimento do seu diagnóstico. Trata-se de estudo exploratório, descritivo, com abordagem qualitativa, utilizando a História Oral Temática para coleta e análise de dados. Foram entrevistadas dez mulheres com aids em um Hospital de referência em Fortaleza-CE, de dezembro de 2004 a março de 2005. Para coleta de dados utilizou-se roteiro semi-estruturado, cujos dados foram categorizados. Os resultados revelam diferentes formas de enfrentamentos relacionados à fragilidade da descoberta do diagnóstico, à necessidade de ocultar a infecção decorrente da discriminação e preconceito que vivenciam, e à constante percepção da morte; além de emitirem sentimentos, como vergonha, preocupação com a família, abandono, solidão, tristeza, medo da morte, ansiedade. Concluiu-se que, apesar de mais de duas décadas de epidemia, fica evidente as dificuldades enfrentadas pelas mulheres ao vivenciarem sua infecção.Este estudio tuvo como objetivo aprender cómo las mujeres con sida enfrentan el cotidiano después de conocer su diagnóstico. Se trata de un estudio exploratorio, descriptivo, con abordaje cualitativo, utilizando la Historia Oral Temática para la recolección y el análisis de los datos. Fueron entrevistadas diez mujeres con sida en un Hospital de referencia en Fortaleza-CE, de diciembre del 2004 a marzo del 2005. Para la recolección de los datos se utilizó una guía semi-estructurada, cuyos datos fueron categorizados. Los resultados revelan diferentes formas de enfrentamiento relacionados a la fragilidad del descubrimiento del diagnóstico, a la necesidad de ocultar la infección consecuente de la discriminación y prejuicios que vivencian, y a la constante percepción de la muerte; además de reflejar sentimientos, como vergüenza, preocupación con la familia, abandono, soledad, tristeza, miedo a la muerte, ansiedad. Se concluyó que, pese

  10. Morbidade referida e seus condicionantes em crianças de 5 a 9 anos em Sobral, CE, Brasil Reported morbidity and its conditionings in children 5 to 9 years old in Sobral, CE, Brazil

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    Ivana Cristina de Holanda Cunha Barreto

    2010-03-01

    Full Text Available OBJETIVO: Descrever a morbidade referida em crianças de 5 a 9 anos e analisar seus possíveis condicionantes. METODOLOGIA: Corte de base populacional com amostra aleatória e representativa em crianças de 5 a 9 anos da zona urbana de Sobral - CE, Brasil. Entrevistas domiciliares com 3.276 crianças e exame clínico em 2.594. A morbidade referida foi classificada segundo a CID-10. O desfecho analisado foi morbidade referida nos últimos 15 dias, utilizando Stata 7.0. RESULTADOS: 43,9% das crianças apresentaram morbidade referida: Doenças do Aparelho Respiratório (DAR, 28,7%; doenças da pele, 3,4%; doenças infecciosas, 2,2%. Daquelas que adoeceram, 41,5% procuraram atendimento. Dessas, 77,4% em Unidades de Saúde Familiar. Apresentaram maiores chances de DAR as crianças com as seguintes características: residir no núcleo urbano principal do município, ter antecedente de desnutrição e frequentar escola, com um valor de ODDS Ratio, respectivamente de 1,48 (IC95%1,10-1,99, 1,30 (IC95%1,05-1,60 e 1,54 (IC95%1,02-2,32. DISCUSSÃO: Chamou a atenção a elevada prevalência de DAR em crianças do núcleo urbano principal, cerca de duas vezes maior que a observada em outros estudos de metodologia similar, levantando hipóteses de sobrerelato ou poluição ambiental. A maioria das crianças apresentou problemas de saúde de menor gravidade e teve acesso facilitado aos serviços de saúde, principalmente ao PSF. CONCLUSÕES: Serão necessários novos estudos para identificar possíveis causas da elevada prevalência de DAR em crianças do núcleo urbano principal do município. As ocasiões em que as crianças demandam os serviços de saúde da família por doenças de baixa gravidade podem ser aproveitadas para medidas de prevenção e promoção da saúde.INTRODUCTION: This study was based on a random sample of 3,276 children aged between 5 and 9 years from the urban region of Sobral - CE, Brazil. OBJECTIVE: The main goal was to describe

  11. Loucura em liberdade: vivências e convivências em Crato-CE (1930-1970

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    Cleide Correia de Oliveira

    2003-04-01

    Full Text Available Este estudo teve como objetivos: identificar os personagens mais significativos no imaginário social e narrar as suas vivências e convivências. É um estudo sócio-histórico. As fontes documentais foram orais (entrevistas semi-estruturadas e escritas. A interpretação dos achados apoiou-se nos estudos arqueológicos de Foucault sobre a história da loucura, e em autores que estudaram os temas: loucura psiquiatria e reforma psiquiátrica. A loucura narrada no cenário do Crato indica a existência de uma multiplicidade que revela a diversidade, transcendendo o paradigma psiquiátrico tradicional, cujo princípio é a idéia de que o louco deve ser isolado da sociedade. Espera-se que esta pesquisa contribua para o debate sobre a prática dos profissionais de enfermagem no campo da psiquiatria/saúde mental.

  12. Conhecimento de farmacêuticos sobre aleitamento materno: um estudo nas farmácias comerciais em FORTALEZA-CE

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    Luzia Izabel Mesquita Moreira da Silva

    2013-07-01

    Full Text Available Objetivo: Avaliar o conhecimento de farmacêuticos que atuam em farmácias comerciais de Fortaleza-CE, Brasil, sobre aleitamento materno. Métodos: Trata-se de um estudo observacional, descritivo e transversal. Foi utilizado um questionário abordando o perfil dos farmacêuticos e os conhecimentos gerais sobre aleitamento materno e Norma Brasileira de Comercialização de Alimentos para Lactentes e Crianças de Primeira Infância, Bicos, Chupetas e Mamadeiras (NBCAL. A coleta de dados ocorreu no período de janeiro a março de 2011. Através de sorteio, selecionaram-se 82 farmácias comerciais, correspondendo a 15,5% do total das farmácias de Fortaleza, quando realizou-se o contato com seus respectivos profissionais farmacêuticos. O questionário foi aplicado com 67 farmacêuticos. Os resultados foram submetidos à análise estatística através dos programas Epi Info v. 3.5.1 e SigmaPlot v. 10.0. Resultados: Entre os participantes da pesquisa, 72% (n=48 eram do sexo feminino; 35,8% (n=24 estão formados há mais de dez anos; 49,3% (n=33 trabalham em farmácia comercial há menos de cinco anos; e 52,2% (n=35 exercem atividade profissional em outros estabelecimentos. O nível de conhecimento foi avaliado como regular para 71,7 % (n=48 dos entrevistados; insuficiente para 17,9% (n=12; e bom para 10,4% (n= 07. Esse baixo desempenho, não atingindo o escore máximo, foi associado ao tempo de exercício na profissão, observando-se que os profissionais formados há mais de dez anos apresentaram menor nível de conhecimento. Conclusão: Os profissionais entrevistados reconhecem a importância do aleitamento materno tanto para a saúde do bebê quanto para a da mãe. Entretanto, faltam conhecimentos sobre informações relevantes referentes ao manejo correto da amamentação, principalmente entre aqueles que se graduaram há mais tempo.

  13. Performance of YAG:Ce Scintillators for Low-Energy Electron Detectors in S(T)EM

    Czech Academy of Sciences Publication Activity Database

    Lalinský, Ondřej; Bok, Jan; Schauer, Petr; Frank, Luděk

    Praha: Czechoslovak Microscopy Society, 2014. ISBN 978-80-260-6720-7. [International Microscopy Congres /18./. Praha (CZ), 07.09.2014-12.09.2014] R&D Projects: GA TA ČR TE01020118; GA MŠk EE.2.3.20.0103 Institutional support: RVO:68081731 Keywords : scintillator * YAG:Ce * single crystal * electron detector * SEM * STEM * low- energy electron * cathodoluminescence Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  14. Metallic oxides supported in CeO{sub 2} and CeO{sub 2}-La{sub 2} O{sub 3} for low temperature shift reaction; Oxidos metalicos suportados em CeO{sub 2} e CeO{sub 2}-La{sub 2} O{sub 3} para reacao shift a baixa temperatura

    Energy Technology Data Exchange (ETDEWEB)

    Maluf, Silvia Salua; Assaf, Elisabete Moreira [Universidade de Sao Paulo (USP), Sao Carlos, SP (Brazil). Inst. de Quimica]. E-mail: sil_maluf@iqsc.usp.br

    2008-07-01

    This work studied copper and zinc oxides supported in CeO{sub 2} and CeO{sub 2}/La{sub 2}O{sub 3}. The catalytic tests for low temperature shift reaction, carried out for samples, showed the Cu-Ce catalyst presents the highest value of CO conversion (50%) and after the Cu-Ce-La catalysts (30%). The other catalysts showed CO conversion in range of 15%. This behavior is related with surface area, and also with the amount of Cu in the surface of samples (author)

  15. Uso de práticas integrativas e complementares por doulas em maternidades de Fortaleza (CE) e Campinas (SP)

    OpenAIRE

    Raimunda Magalhães da Silva; Herla Maria Furtado Jorge; Regina Yoshie Matsue; Antonio Rodrigues Ferreira Junior; Nelson Filice de Barros

    2016-01-01

    Resumo Objetivou-se analisar as Práticas Integrativas e Complementares (PICs) utilizadas por doulas nos municípios de Fortaleza (CE) e Campinas (SP). É um estudo de natureza qualitativa, com 15 doulas: nove de Fortaleza e seis de Campinas. Os dados foram coletados no segundo semestre de 2010, mediante a realização de entrevistas semiestruturadas, e organizados seguindo a técnica da Análise de Con teúdo na modalidade temática. A interpretação dos resultados baseou-se na noção de que a instituc...

  16. Condições higiênico-sanitárias na comercialização de pescados em Sobral − CE | Hygienic-sanitary conditions in fish trading in Sobral − CE

    Directory of Open Access Journals (Sweden)

    Mauro Vinicius Dutra Girão

    2015-11-01

    Full Text Available Este trabalho objetiva avaliar as condições higiênico-sanitárias dos comércios de pescado particulares do município de Sobral − CE, através da análise visual e utilização de um checklist, baseado na RDC no 216. As informações foram coletadas através da observação da rotina de trabalho dos estabelecimentos registrados na Vigilância Sanitária Municipal durante inspeções mensais em um período de três meses. Para cada critério contido no checklist, foi realizada uma média das conformidades e não conformidades e quantificação do percentual de acertos de cada. Os estabelecimentos inspecionados encontram-se em condições de funcionamento que oferecem riscos moderados de contaminação dos pescados. Dentre os fatores de risco de contaminação encontram-se a Edificação, devido à presença de insetos, que são potenciais vetores mecânicos de microorganismos, a Higienização de utensílios, devido as não conformidades quanto à disposição dos equipamentos para o adequado fluxo dos trabalhadores, infiltrações, telas, ralos sinfonados, caixas de gorduras, luminárias, instalações elétricas e sanitárias, e Manipuladores, que falavam sobre o alimento, manuseavam dinheiro, não utilizavam cabelos presos e utilizavam adornos. Mesmo observando um despreparo das pessoas envolvidas na atividade, observa-se uma tendência à adequação à legislação sanitária em prol da qualidade do alimento. =============================================== The aim of this study was to evaluate the sanitary conditions of the fish markets in the city of Sobral, CE, using visual analysis and a checklist based on the RDC 216. The information was collected over a period of three months during monthly inspections in fish market establishments registered with the Brazilian Health Surveillance town. We calculated the percentage of compliance/non-compliance for each checklist item. Each of the inspected establishments showed signs of moderate

  17. RELAÇÃO ENTRE IDADE E CAPACIDADE FUNCIONAL DE IDOSAS RESIDENTES EM INSTITUIÇÕES DE LONGA PERMANÊNCIA NA CIDADE DE FORTALEZA/CE

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    Darling Kescia Araújo Peixoto Braga

    2014-12-01

    Full Text Available Introdução: O envelhecimento gera desgastes fisiológicos próprios. O sistema de valores socioculturais ocidentais e a atual configuração dos arranjos familiares associados aumenta a institucionalização de idosos, que pela fragilidade podem ter déficits na execução das atividades básicas de vida diária (ABVD's e cognição. Objetivo: Avaliar o desempenho nas ABVD, considerando a faixa etária de mulheres idosas residentes em duas Instituições de Longa Permanência para Idosos (ILPI´s na cidade de Fortaleza/CE. Métodos: Estudo seccional, realizado no período de Outubro a Dezembro de 2013 através de um censo com 24 idosas residentes em duas ILPI's. A coleta de dados foi realizada em duas etapas: formulário com caracterização da amostra e o questionário de ABVD de Barthel. Resultados: A amostra possui idade média de 80,04 anos (± 7,91; mín, = 65,0 e máx. = 90,0, eram solteira (66,6%, com baixa escolaridade (33,3% analfabetas e 33,3% com primário completo, procedentes do interior do Estado (58,3% e residiam na instituição há menos de cinco anos (58,3%. O Índice de Barthel revelou que a maioria (75% eram independentes para a realização das ABVDs, sem influenciada da faixa etária. Conclusão: As idosas residentes nas ILPI apresentam independência funcional nas ABVD e sem influência da idade.

  18. Thermoelastic and structural properties of ionically conducting cerate perovskites: (I) BaCeO3 at low temperature in the <em>Pbnm> phase

    DEFF Research Database (Denmark)

    Knight, Kevin S.; Bonanos, Nikolaos

    2013-01-01

    The thermoelastic and structural properties of BaCeO3 perovskite in the Pbnm phase field have been studied using high resolution neutron diffractometry at 37 temperatures between 2 K and 350 K. From a simultaneous fit of the isochoric heat capacity and unit cell volume, the vibrational density of...... parameter. Structural parameters are presented as the amplitudes of the seven symmetry-adapted basis-vectors of the aristotype phase, and a structural basis for the temperature-dependence of the bond lengths is outlined. The critical exponent associated with the temperature variation of the primary order...

  19. MORFODINÂMICA FLUVIAL EM ÁREAS SEMIÁRIDAS: DISCUTINDO O VALE DO RIO JAGUARIBE-CE-BRASIL

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    Andréa Almeida Cavalcante

    2012-08-01

    Full Text Available O trabalho discute o funcionamento dos ambientes fluviais em regiões semiáridas, trazendo, como estudo de caso, um recorte espacial para o vale do Jaguaribe, Estado do Ceará. Na discussão são apresentadas questões sobre o barramento de cursos d’água e suas repercussões na morfodinâmica de canais. Para a realização do trabalho, foram utilizados dados do monitoramento de 11 (onze estações distribuídas entre a barragem do Castanhão e a cidade de Jaguaruana, onde foram levantadas medições de vazão, concentração de sedimentos, largura e profundidade do canal. O perfil longitudinal foi feito a partir de dados de SRTM, utilizando o software ArcGis 9.3. Os resultados mostram que os processos fluviais são rápidos e intensos em regiões semiáridas, necessitando o aprofundamento de estudos diferenciados em relação àqueles realizados em regiões tropicais úmidas. No vale do Jaguaribe, os dados mostram que grandes barramentos mudam as condições morfológicas de jusante, entretanto, levam algum tempo para serem percebidas. Tais alterações são observadas à jusante das barragens de Orós, Várzea do Boi e Castanhão. A jusante da barragem do Castanhão as mudanças são menos perceptíveis, haja vista o tempo de construção da mesma (2002. Se morfologicamente as alterações provocadas por um barramento podem levar um tempo maior para serem visíveis, hidrológica e sedimentologicamente as variações podem ser vistas de modo mais rápido. Nesse sentido, altera-se principalmente as amplitudes de vazões que influenciam na redução de descarga sólida e, consequentemente, alteram padrões de canais a médio e longo prazo.

  20. IMPLANTAÇÃO DA AUDITORIA BASEADA EM RISCO EM UMA ENTIDADE DO "SISTEMA S": O CASO DO SEBRAE/CE

    OpenAIRE

    Ruth Carvalho de Santana Pinho; Leonardo Brandão Bezerra

    2015-01-01

    Com a crescente complexidade dos negócios, muitas entidades viram a necessidade de um controle maior sobre o risco para que seus objetivos pudessem ser atingidos. O presente trabalho discorre sobre a Auditoria Baseada em Risco (ABR), evidenciando suas principais características. O estudo apresenta-se relevante tanto para o meio empresarial, evidenciando as etapas de implantação dessa metodologia, como para o meio acadêmico, que possui poucos estudos relacionados ao tema, conforme observações ...

  1. Uso de práticas integrativas e complementares por doulas em maternidades de Fortaleza (CE e Campinas (SP

    Directory of Open Access Journals (Sweden)

    Raimunda Magalhães da Silva

    2016-03-01

    Full Text Available Resumo Objetivou-se analisar as Práticas Integrativas e Complementares (PICs utilizadas por doulas nos municípios de Fortaleza (CE e Campinas (SP. É um estudo de natureza qualitativa, com 15 doulas: nove de Fortaleza e seis de Campinas. Os dados foram coletados no segundo semestre de 2010, mediante a realização de entrevistas semiestruturadas, e organizados seguindo a técnica da Análise de Con teúdo na modalidade temática. A interpretação dos resultados baseou-se na noção de que a institucio nalização dos saberes se dá pela conformação de núcleos e de campos. O núcleo demarca a identidade de uma área de saber e de práticas profissionais; e o campo, um espaço de limites imprecisos entre as disciplinas, mas que pode ser submetido a conflitos. Observou-se que o suporte das doulas permeia uma variedade de práticas emolduradas na Medicina Tradicional (MT e das PICs. Essas práticas contri buíram para a diminuição do tempo de trabalho de parto, melhor controle da dor, ajuda na tomada de decisões e empoderamento da mulher. Compreende -se que o espaço de atuação da doula e o uso de PICs convergem para a singularidade, respeito e autonomia da mulher e propõem um novo modelo de saberes e práticas centrado na importância do processo natural do parto.

  2. IMPLANTAÇÃO DA AUDITORIA BASEADA EM RISCO EM UMA ENTIDADE DO "SISTEMA S": O CASO DO SEBRAE/CE

    Directory of Open Access Journals (Sweden)

    Ruth Carvalho de Santana Pinho

    2015-12-01

    Full Text Available Com a crescente complexidade dos negócios, muitas entidades viram a necessidade de um controle maior sobre o risco para que seus objetivos pudessem ser atingidos. O presente trabalho discorre sobre a Auditoria Baseada em Risco (ABR, evidenciando suas principais características. O estudo apresenta-se relevante tanto para o meio empresarial, evidenciando as etapas de implantação dessa metodologia, como para o meio acadêmico, que possui poucos estudos relacionados ao tema, conforme observações empíricas. Assim, coube como pergunta de pesquisa: Quais fatores contribuem para a adequada implantação de uma Auditoria Baseada em Risco? Tem-se como objetivo geral deste estudo, identificar os fatores de sucesso na implantação da Auditoria Baseada em Risco (ABR. Escolheu-se como procedimento de pesquisa o estudo de caso. Os dados foram obtidos por intermédio da documentação oficial de implantação da ABR na entidade a qual descreve todas as etapas de implantação, além de aplicação de entrevista e questionário entre os auditores internos da empresa e gestores das áreas de Licitação, Contabilidade e Jurídico Concluiu-se que a ABR é uma ferramenta importante para empresas que desejam avaliação independente para a Gestão de Riscos, sendo necessário um plano bem estruturado de implantação para êxito desta. Destarte, uma Auditoria Interna Tradicional bem desenvolvida, ou seja, que mantém um controle interno eficaz, se torna uma característica facilitadora para a mudança de escopo, pois para a correta implantação da ABR é necessário um ambiente de gestão robusto e o efetivo envolvimento da equipe de auditoria.

  3. Síndrome de möbius: caracterização de crianças atendidas em uma instituição de Fortaleza-CE - doi: 10.5020/18061230.2012.p37

    OpenAIRE

    Ismênia de Carvalho Brasileiro; Adriana Mary Nunes Costa; Milena Santos da Costa; Thereza Maria Magalhães Moreira

    2012-01-01

    Descrever as características sociodemográficas e clínicas de um grupo de crianças com Síndrome de Möbius. Métodos: A pesquisa, quantitativa, descritiva, documental e transversal foi realizada em um serviço de estimulação precoce, no município de Fortaleza-CE, Brasil, em 2009. Resultados: Na análise de nove crianças em atendimento, observou-se que as mães eram jovens ao engravidar (média de 24 anos), tinham relacionamentos estáveis; metade havia cursado o ensino médio e outra metade, o funda...

  4. Avaliação farmacognostica e da rotulagem das drogas vegetais boldo-do-chile (Peumus boldus Molina e camomila (Matricaria recutita L. comercializadas em Fortaleza, CE

    Directory of Open Access Journals (Sweden)

    F.P. SOARES

    2015-09-01

    Full Text Available RESUMO Boldo-do-chile (Peumus boldus e camomila (Matricaria recutita são plantas empregadas na fitoterapia principalmente para o tratamento de desordens hepáticas e intestinais, atuando também como anti-inflamatório e antiespasmódico, respectivamente. Por isso, o presente trabalho objetivou avaliar a qualidade farmacognostica dessas drogas vegetais comercializadas em Fortaleza (CE, além das informações de suas rotulagens. Quarenta e duas amostras de boldo, e quarenta e cinco amostras de camomila, procedentes de farmácias, de lojas de produtos naturais e de bancas de raizeiros, foram analisadas quanto à autenticidade, à pureza e às informações contidas na rotulagem desses produtos conforme legislação vigente. Na verificação de impurezas, 35,7% das amostras de boldo e 57,7% das amostras de camomila excederam o teor máximo de matéria estranha; no teor de cinzas totais, 33,3% das amostras de boldo foram reprovadas; rotulagens das amostras de boldo (100% e de camomila (96,6% apresentaram erros ou ausência de informações. Os resultados das análises confirmam, portanto, a necessidade urgente de melhor fiscalização e intervenção na produção e venda dessas e de outras drogas vegetais para adequação às normas vigentes.

  5. Necessidades educacionais dos profissionais da Estratégia Saúde da Família (ESF): possibilidades de Educação em Saúde no município de Fortaleza (CE) Educational needs assessment of Family Health Strategy (FHS) professionals: possibilities of health education in Fortaleza Las necesidades educativas de los profesionales de la Estrategia de Salud Familiar (ESF): las posibilidades de la Educación para la Salud en Fortaleza (CE)

    OpenAIRE

    Tatiana Monteiro Fiúza; Marco Túlio Aguiar Mourão Ribeiro; Kilma Wanderley Lopes Gomes; Mayrá Lobato Pequeno; Ivana Cristina de Holanda Cunha Barreto; Alcides Silva de Miranda; Pedro Renan Santos de Oliveira; Renan Magalhães Montenegro Junior

    2012-01-01

    As reformas curriculares e a mudança do perfil na formação de profissionais da saúde apresentam muitos desafios. O objetivo deste estudo foi caracterizar as necessidades educacionais em saúde percebidas e representadas pelos profissionais de nível superior que atuam na Estratégia Saúde da Família (ESF) do município de Fortaleza/CE, recém-aprovados em concurso de âmbito municipal. Trata-se de um estudo descritivo com duas etapas. Um estudo transversal em 2006 com a...

  6. Prevalência de asma em adolescentes na cidade de Fortaleza, CE Prevalence of asthma among adolescents in the city of Fortaleza, Brazil

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    Maria de Fátima Gomes de Luna

    2009-11-01

    Full Text Available OBJETIVO: Avaliar a prevalência de asma em adolescentes (13-14 anos na cidade de Fortaleza, CE. MÉTODOS: Estudo transversal utilizando o questionário do International Study of Asthma and Allergies in Childhood e envolvendo 3.015 adolescentes de escolas públicas e privadas entre 2006 e 2007. RESULTADOS: As prevalências de "sibilos alguma vez na vida", "sibilos nos últimos doze meses" (asma ativa e "asma alguma vez na vida" (asma diagnosticada foram, respectivamente, 44,1%, 22,6% e 11,6%. As prevalências de "sibilos alguma vez na vida" (p = 0,001, "1-3 crises de sibilos nos últimos 12 meses" (p = 0,001; asma ativa (p = 0,002; "sono interrompido por sibilos menos que uma vez por semana" (p OBJECTIVE: To determine the prevalence of asthma among adolescents (13-14 years of age in the city of Fortaleza, Brazil. METHODS: This was a cross-sectional study involving 3,015 adolescents at public and private schools between 2006 and 2007. The participants completed the International Study of Asthma and Allergies in Childhood questionnaire. RESULTS: The prevalences of "wheezing ever", "wheezing within the last 12 months" (active asthma and "asthma ever" (physician-diagnosed asthma were 44.1%, 22.6% and 11.6%, respectively. The prevalences of "wheezing ever" (p = 0.001, "1-3 wheezing attacks within the last 12 months" (p = 0.001, active asthma (p = 0.002, "sleep disturbed due to wheezing less than one night per week" (p < 0.001 and "dry cough at night" (p < 0.001 were higher among girls. Private school students presented higher prevalences of "wheezing ever", active asthma, "1-3 wheezing attacks within the last 12 months", "4-12 wheezing attacks within the last 12 months" and physician-diagnosed asthma (p < 0.001 for all, as well as of "exercise-induced wheezing" (p = 0.032. CONCLUSIONS: The prevalence of asthma and asthma-related symptoms in students aged 13-14 years in the city of Fortaleza, Brazil, was high, predominantly among girls and private

  7. Sistemas interfaceados de análise por injeção em fluxo e eletroforese capilar (FIA - CE: desafios, aplicações e perspectivas

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    Miranda Carlos E. S.

    2002-01-01

    Full Text Available A review about the state-of-the-art of flow injection analysis (FIA -- capillary electrophoresis (CE systems is presented. The basic principles of flow injection and capillary electrophoresis are briefly revised. The main aspects of the FIA-CE hybridization, including advantages and shortcomings, are discussed. Some applications involving all different designs are also presented. This review covers the literature from 1997 up to 2000.

  8. Implantação do Programa Saúde na escola em Fortaleza-CE: atuação de equipe da Estratégia Saúde da Família Implantación del Programa de Salud Escolar en Fortaleza-CE: desempeño de equipo de la Estrategia Salud de la Familia School Health Program implementation in Fortaleza-CE: performance of the Family Health Strategy staff

    Directory of Open Access Journals (Sweden)

    Lindelvania Matias de Santiago

    2012-12-01

    Full Text Available Este trabalho relata a experiência da implantação do Programa Saúde na Escola (PSE por uma equipe da Estratégia Saúde da Família (ESF em uma escola pública em Fortaleza-CE. As atividades desenvolvidas incluíram seminário de implantação do PSE com os docentes e integrantes da ESF, oficinas com os estudantes, avaliação clinica e odontológica dos adolescentes e entrega de Cadernetas de Saúde do Adolescente. A implantação do PSE permitiu aos profissionais de saúde a percepção do seu papel social de educador e possibilitou aos adolescentes maior contato com a equipe da ESF. A aproximação entre escola e ESF é fundamental para ajudar os adolescentes a transformarem a informação científica em comportamentos saudáveis.Este artículo relata la experiencia de implementación del Programa de Salud Escolar (PSE por un equipo de la Estrategia de Salud de la Familia (ESF en una escuela pública en Fortaleza-CE, Brasil. Las actividades incluyeron seminario de despliegue del PSE con los maestros y los miembros de la ESF, talleres con los estudiantes, la evaluación clínica y dental de los adolescentes y la entrega de folletos de Salud del Adolescente. La aplicación del PSE permitió a los profesionales de salud a darse cuenta de su papel social como educadores y permitió a los adolescentes un mayor contacto con el personal de la ESF. El acercamiento entre la escuela y el FSE es crucial para ayudar a los adolescentes a transformar el conocimiento científico en comportamientos saludables.This work reports the experience of implementation of the School Health Program (PSE by a team from the Family Health Strategy (FHS in a public school in Fortaleza-CE , Brazil. The activities included conference about the deployment of the PSE with teachers and members of the FHS, workshops with students, clinical and dental assessment for adolescents and delivery of Booklets of Adolescent Health. The implementation of the PSE allowed health

  9. Gravidez em adolescentes de uma unidade municipal de saúde em Fortaleza - Ceará Embarazo en adolescentes de una unidad municipal de salud en Fortaleza - Ceára (Brasil Pregnancy in adolescents of a city health unit in Fortaleza - Ceára (Brazil

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    Conceição de Maria Arcanjo

    2007-09-01

    Full Text Available Estudo quantitativo com objetivo de conhecer a gravidez na adolescência em unidade municipal de saúde, Fortaleza-CE. A amostra foi composta por 40 adolescentes. Como resultado, encontramos: 20% estavam entre 14 e 15 anos, 7,5% eram solteiras, 5%, casadas, 7,5% tinham união consensual; 60% tinham entre 16 e 17 anos, 5% eram solteiras, 7,5%, casadas, 47,5% tinham união consensual; 20% tinham entre 18 e 19 anos, 12,5% eram solteiras, 7,5%, casadas. E, ainda: 17,5% tiveram experiência do aborto, 50% deixaram de estudar por causa da gravidez, 25% não gostam de estudar, 20% não acham importante, 57,5% iniciaram pré-natal com três a quatro meses de gestação, 80% dos pais assumem a paternidade, 70% delas continuavam morando com a família, 70% receberam orientações sobre gravidez, 60% não utilizavam método contraceptivo, 37,5% desejam ser dona de casa, 27,5% não têm planos para o futuro. Concluímos que as adolescentes engravidam em faixa etária precoce, não percebem os riscos inerentes à gravidez e deixam de lado o estudo, lazer, vaidade ou mesmo perspectivas para o futuro. A nosso ver, o estudo pode contribuir para o redimensionamento do trabalho com adolescentes na unidade local do estudo.Estudio cuantitativo con el objetivo de conocer el embarazo en la adolescencia de una unidad municipal de salud, Fortaleza CE (Brasil. La muestra fue compuesta por 40 adolescentes. Como resultado encontramos: 20% estaban entre 14-15 años, 7,5% solteras, 5% casadas, 7,5% unión consensual; 60% entre 16 y 17años, 5% solteras, 7,5% casadas, 47,5% unión consensual; 20% entre 18-19 años, 12,5% solteras, 7,5% casadas. Y todavía 17,5% tuvieran experiencia del aborto, 50% dejaron de estudiar debido el embarazo, 25% no les gusta estudiar, 20% no encuentra importante, 57,5% empezaron prenatal con tres a cuatro meses de la gestación, 80% de los padres asumen la paternidad, 70% continúan viviendo con la familia, 70% recibieran las orientaciones en el

  10. Polluted emission in mineral coal combustor CE4500 in atmospheric bubbling fluidized bed coal; Emissoes poluentes na combustao do carvao mineral CE4500 em reator de leito fluidizado atmosferico borbulhante

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Manoel Carlos Diniz; Samaniego, Julio Edgardo Lindo; Milioli, Fernando Eduardo; Pagliuso, Josmar Davison [Universidade de Sao Paulo (USP), Sao Carlos, SP (Brazil). Escola de Engenharia. Nucleo de Engenharia Termica e Fluidos], e-mail: mcdcosta@petrobras.com.br, e-mail: jelindo@sc.usp.br, e-mail: milioli@sc.usp.br, e-mail: josmar@sc.usp.br

    2006-07-01

    The SO{sub 2}, CO{sub 2}, CO and NO{sub x} polluted gases emission were evaluated in coal combustor with absorption of SO{sub 2} by means of limestone in the pilot-plan for combustor in atmospheric bubbling fluidized bed coal of NETeF. The CE4500 mineral coal (energetic coal with upper average calorific power of 4500 kcal/kg) from of Criciuma region was utilized, with 2.3% of sulfur, 31,6% of ashes, and average diameter of particle of 425 um. The dolomite limestone DP from Ipeuna- SP was utilized with 16.2% of coal, 10.1% of magnesium, and average diameter of particle of 400 um. The pilot-plan has a reactor of square cross-section of 0,5*0,5 m in which it were controlled the excess air level, the velocity of fluidization (U/U{sub mf}), the size of particle grain and the temperature of process. The main variable of analysis was the supplies relation Ca/S. The relationship of 2, 3, 4 and 5 Ca/S at temperature of bed around 850 deg C was used. Concentration discharge gases of reactor were measured and distribution of size grain and chemical composition of the material bed, removal and global coefficient of reaction of sulfation for many cases were determined. The SO{sub 2} emission dropped in asymptotic way for the increment of supplies of rate Ca/S. Increasing Ca/S from 3 to 5 (67%) resulted in a gain of efficiency of absorption between 4 to 21%. The emission of NOx increased lightly by the increment of supplies Ca/S. That result is agreement with current publication, which it attributes this fact to the catalyst effect of CaO to generation of NO{sub x} by means of reduction of CO. (author)

  11. Démantèlement des paysages cuirassés anciens en zones forestières tropicales d'Afrique centrale : formation d'accumulations ferrugineuses actuelles en bas de versantOld ferricrete landscape dismantling in Central Africa rain forest zone: formation of the present downslope iron accumulations

    Science.gov (United States)

    Temgoua, Émile; Bitom, Dieudonné; Bilong, Paul; Lucas, Yves; Pfeifer, Hans-Rudolf

    Present downslope iron accumulations were investigated in the rainforest zone in southern Cameroon. Six clay and Fe-hydroxide dominated patterns have been identified and occur on the lower part of hill slopes. They can be subdivided in three different sequences, related to gentle, moderate or steep slopes. They are discontinuous with respect to the dismantling zone of the old ferricrete cap formed at Cretaceous period. They show a gradual development from a soft Fe-crust (carapace) to a vesicular facies that will, with time, cover the whole landscape again. To cite this article: É. Temgoua et al., C. R. Geoscience 334 (2002) 537-543.

  12. O compartilhamento do cuidado em saúde mental: uma experiência de cogestão de um centro de atenção psicossocial em Fortaleza, CE, apoiada em abordagens psicossociais The partnership in the mental health care: an experience in psicossocial approaches and in the co-management of a mental health community service in Fortaleza/CE

    OpenAIRE

    Maria Gabriela Curubeto Godoy; Ana Paula Fernandes Viana; Kamilla Angélica G. de Vasconcelos; Otorino Bonvini

    2012-01-01

    Este artigo aborda a trajetória de uma experiência comunitária vinculada a uma organização não governamental, o Movimento de Saúde Mental Comunitária do Bom Jardim e a parceria celebrada entre essa entidade e a Secretaria Municipal de Saúde de Fortaleza. Tal parceria vem proporcionando a expansão de ações psicossociais, bem como a cogestão de um Centro de Atenção Psicossocial tipo II inaugurado em 2005 (CAPS Comunitário do Bom Jardim). Geograficamente situado na Regional V, área com os piores...

  13. Doenças respiratórias agudas em serviços de saúde entre 1996 e 2001, Fortaleza, CE

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    Façanha Mônica Cardoso

    2004-01-01

    Full Text Available OBJETIVO: As doenças respiratórias agudas, principalmente as pneumonias, são a causa mais importante de óbito em menores de cinco anos e são responsáveis por doença grave nos maiores de 60 anos. O estudo realizado tem como objetivo descrever as principais características epidemiológicas dos casos de doenças respiratórias agudas notificadas pelas unidades de saúde. MÉTODOS: Todos os registros de atendimentos de pacientes com doença respiratória aguda, no período entre 1996 e 2001, foram revistos semanalmente, em formulário específico, a partir dos boletins de atendimento médico preenchidos por 100 unidades públicas de saúde. Os dados foram classificados em não pneumonia e pneumonia por faixa etária. RESULTADOS: Foram informados 2.050.845 casos de doença respiratória aguda no período estudado. Os meses com maior número de casos foram maio e junho. A faixa etária mais acometida foi a de um a quatro anos, com cerca do dobro do número de casos das outras faixas etárias. Pneumonias representaram, aproximadamente, 7,7% dos casos. CONCLUSÕES: O acompanhamento das doenças respiratórias agudas serve para mostrar sua magnitude em termos numéricos, e estimular seu diagnóstico apropriado, tratamento precoce e prevenção, tanto das complicações, quanto de sua ocorrência.

  14. Atividade financeira e moeda: análise da experiência do conjunto palmeiras em Fortaleza-CE Financial activity and currency: analisys of the experience of “conjunto palmeiras” in Fortaleza-CE

    Directory of Open Access Journals (Sweden)

    Uinie Caminha

    2011-06-01

    Full Text Available O Conselho Monetário Nacional (CMN regula o acesso e fiscaliza as atividades das instituições financeiras que participam do Sistema Financeiro Nacional (SFN. Esse controle do sfn é essencial, pois o sistema financeiro é suscetível a crises de confiança e saques em massa, e ainda instrumentaliza políticas monetárias com o intuito de controlar índices inflacionários. Um dos mecanismos de controle inflacionário é a emissão de papel moeda, sendo que, de acordo com a Constituição Federal de 1988, a incumbência de emitir, controlar e regulamentar a moeda oficial é exclusiva da União. No entanto, vêm crescendo experiências de economia solidária, na qual se encontram redes de produção e consumo, além de meios alternativos de pagamento. O objetivo deste artigo é analisar a experiência no bairro Conjunto Palmeiras, na cidade de Fortaleza, Ceará, sua estrutura, seus projetos, e especialmente a emissão da moeda social do bairro (palma, P$, bem como um projeto de microcrédito e financiamento para os moradores locais, verificando se há possibilidades de integrar tais práticas ao SFN, uma vez que, até então, são atividades que deveriam ser exercidas privativamente por instituições financeiras.The National Monetary Council (CMN regulates and controls the activities of financial institutions which participate in National Financial System (SFN. Such control is critical since the financial system if suceptible to confindence crisis and massive withdrawls, and yet engages monetary policies aiming at controling inflation rates. One of the instruments to control inflation is the issuance of currency since, according to Federal Contituition of 1988, the incumbecy of issuing, controlling and regulation the offical currency if exclusive of the Union. However, several experiences of “solidary economy” in which production and consumption networks are found, in addition to alternative means of payment. The scope of this article is

  15. RELAÇÃO ENTRE IDADE E CAPACIDADE FUNCIONAL DE IDOSAS RESIDENTES EM INSTITUIÇÕES DE LONGA PERMANÊNCIA NA CIDADE DE FORTALEZA/CE

    OpenAIRE

    Darling Kescia Araújo Peixoto Braga; Bruno Ricarth Domiciano; Mayara Paz Albino dos Santos; Thiago Brasileiro de Vasconcelos; Raimunda Hermelinda Maia Macena

    2014-01-01

    Introdução: O envelhecimento gera desgastes fisiológicos próprios. O sistema de valores socioculturais ocidentais e a atual configuração dos arranjos familiares associados aumenta a institucionalização de idosos, que pela fragilidade podem ter déficits na execução das atividades básicas de vida diária (ABVD's) e cognição. Objetivo: Avaliar o desempenho nas ABVD, considerando a faixa etária de mulheres idosas residentes em duas Instituições de Longa Permanência para Idosos (ILPI´s) na cidade d...

  16. O compartilhamento do cuidado em saúde mental: uma experiência de cogestão de um centro de atenção psicossocial em Fortaleza, CE, apoiada em abordagens psicossociais The partnership in the mental health care: an experience in psicossocial approaches and in the co-management of a mental health community service in Fortaleza/CE

    Directory of Open Access Journals (Sweden)

    Maria Gabriela Curubeto Godoy

    2012-05-01

    Full Text Available Este artigo aborda a trajetória de uma experiência comunitária vinculada a uma organização não governamental, o Movimento de Saúde Mental Comunitária do Bom Jardim e a parceria celebrada entre essa entidade e a Secretaria Municipal de Saúde de Fortaleza. Tal parceria vem proporcionando a expansão de ações psicossociais, bem como a cogestão de um Centro de Atenção Psicossocial tipo II inaugurado em 2005 (CAPS Comunitário do Bom Jardim. Geograficamente situado na Regional V, área com os piores indicadores sociais e sanitários de Fortaleza, o Movimento de Saúde Mental Comunitária do Bom Jardim oferta atividades como Terapia Comunitária, Biodança, Arteterapia, Grupos de autoestima, Massoterapia, Reiki, Shiatsu, Quiropraxia, Oficinas de arte, música e teatro, cursos profissionalizantes e atividades lúdicas e educativas para diversas faixas etárias da população do bairro. A articulação entre as ações implementadas pelo Movimento de Saúde Mental Comunitária do Bom Jardim e a parceria com a Secretaria Municipal de Saúde de Fortaleza apresenta desafios e possibilidades na tentativa de construção da integralidade no campo da atenção psicossocial. Neste artigo apresentamos a trajetória histórica da referida entidade, descrevemos algumas de suas principais atividades e realizamos uma breve análise da parceria com a Secretaria Municipal de Saúde e o processo de cogestão do Centro de Atenção Psicossocial, apontando também alguns desafios e possibilidades encontradas nessa tentativa de convergência entre uma concepção de trabalho comunitário e a lógica burocrático-normativa sobre a qual geralmente se sustenta a atuação de instituições estatais de saúde.This is the report of the partnership experience between a nongovernmental organization that works with Mental Health and the Health Municipal Commission of Fortaleza/Ceará. This partnership has expanded several psychosocial actions as Community Therapy

  17. Profile of yttrium segregation in BaCe{sub 0,9}Y{sub 0,1}O{sub 3-{delta}} as function of sintering temperature; Perfil da segregacao do itrio em BaCe{sub 0,9}Y{sub 0,1}O{sub 3-{delta}} em funcao da temperatura de sinterizacao

    Energy Technology Data Exchange (ETDEWEB)

    Hosken, C.M.; Souza, D.P.F. de, E-mail: camila.hosken@gmail.co [Universidade Federal de Sao Carlos (LAPCEC/UFSCar), SP (Brazil). Programa de Pos-Graduacao em Ciencia e Engenharia de Materiais. Lab. de Preparacao e Caracterizacao Eletrica em Ceramicas

    2010-07-01

    Researches on solid oxide fuel cells indicate barium cerate perovskite as a very attractive material for using as electrolyte due to its high protonic conductivity. The objective of this work is investigate the yttrium segregation during sintering of BaCe{sub 0,9}Y{sub 0,1}O{sub 3-{delta}} doped with Zn O as a sintering aid. The powders were prepared by citrate process. Powders were isostatic pressed into pellets and sintered in air at 1200, 1275, 1325 and 1400 deg C. The samples were characterized by scanning electron microscopy, X-ray diffraction and impedance spectroscopy. Secondary phase containing Yttrium and Cerium was detected as sintering temperature increased. Increase of the lattice parameter and activation energy for electrical conductivity were also detected on samples sintered at 1400 deg C. (author)

  18. Improving CE with PDM

    NARCIS (Netherlands)

    Wognum, P.M. (Nel); Bondarouk, T.V. (Tanya); Weber, F.; Pawar, K.S.; Thoben, K.D.

    2003-01-01

    The concept of Concurrent Engineering (CE) centers around the management of information so that the right information will be at the right place at the right time and in the right format. Product Data Management (PDM) aims to support a CE way of working in product development processes. In specific

  19. Synthesis and characterization of Ce{sub 1-x}SmXO{sub 2-(x/2)} as solid electrolyte for application in IT-SOFCs; Sintese e caracterizacao de Ce{sub 1-x}SmXO{sub 2-(x/2)} como eletrolito solido para aplicacao em IT-SOFCs

    Energy Technology Data Exchange (ETDEWEB)

    Nicodemo, J.P.; Martinelli, A.E.; Nascimento, R.M. [Universidade Federal do Rio Grande do Norte (DECM/UFRN), Natal, RN (Brazil). Dept. de Engenharia de Materiais], e-mail: juli_pivotto@yahoo.com.br; Melo, D.M.A. [Universidade Federal do Rio Grande do Norte (DQ/UFRN), Natal, RN (Brazil). Dept. de Quimica; Cela, B. [Universidade Federal do Rio Grande do Norte (PPGCEM/UFRN), Natal, RN (Brazil). Programa de Pos-Graduacao em Ciencia e Engenharia de Materiais; Macedo, D.A. [Universidade Federal do Rio Grande do Norte (PPGEM/UFRN), Natal, RN (Brazil). Programa de Pos-Graduacao em Engenharia Mecanica

    2008-07-01

    Mixed rare earth doped CeO{sub 2} oxide-based have been extensively studied for use in solid electrolytes for fuel cells. Ceramics-based CeO{sub 2} have high ionic conductivity and enable the operation of solid oxide fuel cells (SOFCs) in intermediate temperatures, in the range of 500 to 750 deg C. In this work, was investigated the Sm{sub 2}O{sub 3} doped CeO{sub 2} by Pechini method to obtain Ce{sub 0,9}Sm{sub 0,1}O{sub 1,95}. The resulting powders were characterized by the chemical composition (EDS) and crystallographic (XRD), thermal analysis (TG/ATD and DTG), and particles morphology (SEM). After calcinations of 500 and 700 deg C for 2 hours were obtained nanosized powders with crystalline structure of cubic phase type fluorite fully formed. (author)

  20. Avaliação de Programas de Gestão por Competências: um Estudo em Organizações da Região Metropolitana de Fortaleza - CE

    Directory of Open Access Journals (Sweden)

    Bianca Patrícia Lopes Rocha

    2012-11-01

    Full Text Available Normal 0 21 false false false PT-BR X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabela normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} A avaliação de programas e a gestão por competências têm sido adotados por grandes empresas no Brasil e são estudados aqui segundo diversas abordagens, passando pelos campos epistemológico, teórico, morfológico e técnico da metodologia quadripolar. No pólo epistemológico são apresentados os aspectos gerais da epistemologia de Bachelard, a epistemologia da gestão por competências e da avaliação de programas. O pólo teórico congrega uma revisão conceitual de algumas abordagens teóricas da gestão por competências: teoria da psicometria, teoria baseada nos recursos (VBR, teoria do capital humano, abordagem americana, abordagem francesa, pós-qualificação taylorismo-fordismo e dialética da competência. No pólo morfológico descrevem-se alguns modelos de gestão por competências e de avaliação de programas educacionais. No pólo técnico buscou-se a confirmação dos pressupostos com base nos pólos anteriores. Através de um survey com aplicação de questionários aos gestores de pessoas e áreas envolvidas no desenvolvimento e/ou implantação dos programas de gestão por competências na região metropolitana de Fortaleza-CE, pode-se concluir que as

  1. Trabalhadores de um hospital escola em Fortaleza-CE: exposição cotidiana à hepatite B | Workers in a teaching hospital in Fortaleza, Ceará, Brazil: daily exposure to hepatitis B

    OpenAIRE

    Ana Gleice da Silveira Mota; Julianna de Freitas Siqueira; Francisco Gilberto Fernandes Pereira; Marta Maria Costa Freitas; Jorge Luíz Nobre Rodrigues; Joselany Áfio Caetano

    2015-01-01

    Estudo transversal, descritivo, quantitativo, que objetivou analisar os acidentes ocupacionais ocorridos entre os profissionais de saúde envolvendo risco para hepatite B, em um hospital escola, em 2013. Analisaram-se 95 notificações, a maioria (73,7%) mulheres, 39 (41,1%) técnico/auxiliar de enfermagem. A faixa etária prevalente foi 20 a 39 anos, com 62 (65,3%) profissionais. A exposição percutânea ocorreu em 77 (81,1%) casos, sendo a agulha com lúmen o principal objeto causador com 35 (36,8%...

  2. Investigation of local magnetism in RZn (R = Ce, Gd, Tb, Dy) and GdCu intermetallic compounds using perturbed angular correlation gamma-gamma spectroscopy; Investigacao do magnetismo local em compostos intermetalicos do tipo RZn (R = Ce, Gd, Tb, Dy) e GdCu pela espectroscopia de correlacao angular gama-gama perturbada

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Brianna Bosch dos

    2010-07-01

    This work presents, from a microscopic point of view, a systematic study of the local magnetism in RZn (R = Ce, Gd, Tb, Dy) and GdCu intermetallic compounds through measurements of hyperfine interactions using the Perturbed Angular Correlation Gamma- Gamma Spectroscopy technique with {sup 111}In {yields} {sup 111}Cd and {sup 140}La {yields} {sup 140}Ce as probe nuclei. As the magnetism in these compounds originates from the 4f electrons of the rare-earth elements it is interesting to observe in a systematic study of RZn compounds the behavior of the magnetic hyperfine field with the variation of the number of 4f electrons in the R element. The use of probe nuclei {sup 140}La {yields} {sup 140}Ce is interesting because Ce{sup +3} ion posses one 4f electron which may contribute to the total hyperfine field, and the results showed anomalous behavior. The results for {sup 111}Cd probe showed that the temperature dependence of the magnetic hyperfine field follows the Brillouin function, and the magnetic hyperfine field decreases linearly with increase of the atomic number of rare earth when plotted as a function of the rare-earth J spin projection, showing that the main contribution to the magnetic hyperfine field in RZn compounds comes from the polarization of the conduction electrons. The results for the electric field gradient measured with {sup 111}Cd for all compounds showed a strong decrease with the atomic number of the rare-earth element. We have therefore assumed that the major contribution to the electric field gradient originates from the 4f electrons of the rare-earths. The measurements of the electric field gradient for GdCu with {sup 111}Cd, after temperature decreases and increases again showed that two different structures, CsCl-type cubic and FeB-type orthorhombic structures co-exist. Finally, it is the first time that measurements of hyperfine parameters have been carried out with theses two probe nuclei in the studied RZn. (author)

  3. CE-BEMS

    DEFF Research Database (Denmark)

    Mohamed, Nader; Lazarova-Molnar, Sanja; Al-Jaroodi, Jameela

    2016-01-01

    costs savings in smart buildings significantly depend on the monitoring and control methods used in the installed BEMS. This paper proposes a Cloud-Enabled BEMS (CE-BEMS) for Smart Buildings. This system can utilize cloud computing to provide enhanced management mechanisms and features for energy...... savings in smart buildings. This system is connected to the cloud to have access to a number of advanced cloud-based services to enhance energy management in smart buildings. In this paper, we discuss the current limitations of BEMS, the conceptual design of the proposed system, and the advantages...

  4. Qualitative evaluation of environmental radiological impact in a phosphate associated uranium conventional mine: Santa Quiteria Project, CE, Brazil; Avaliacao qualitativa do impacto radiologico ambiental em uma mineracao convencional de fosfato com uranio associado: o Projeto Santa Quiteria

    Energy Technology Data Exchange (ETDEWEB)

    Reis, Rocio G. dos; Santo, Aline Sa E., E-mail: rocio@ird.gov.br, E-mail: alinesah@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2013-07-01

    The aim of this study is to identify and evaluate qualitatively the main potential sources of mineral and installation terms of Santa Quiteria, CE, Brazil, evaluating their possible impacts on the environment. The key terms sources in the production of phosphoric acid are usually: the dig of the mines, tailings dams and phospho plaster stack. Thus, this work intends to inform the academic community about this issue, as well as the population in general and also, acting proactively in order to warn about the possible environmental impacts, so that actions to compensate, minimize or avoid these radiological impacts on the environment, can be included in the planning of the industrial mineral project of Santa Quiteria (author)

  5. Biomassa microbiana e matéria orgânica leve em solos sob sistemas agrícolas orgânico e convencional na Chapada da Ibiapaba - CE Microbial biomass and light organic matter in soils under organic and conventional systems in the Chapada da Ibiapaba - CE, Brazil

    Directory of Open Access Journals (Sweden)

    Francisco Alisson da Silva Xavier

    2006-04-01

    Full Text Available Em muitos casos, a substituição da vegetação nativa por sistemas agrícolas resulta em decréscimo nos conteúdos de C e N nos diferentes compartimentos da matéria orgânica do solo. Para testar se as práticas de manejo que priorizam o aporte de resíduos orgânicos promovem aumento dos compartimentos da matéria orgânica mais sensíveis ao manejo, este estudo se propôs estudar áreas de uma propriedade que utiliza um sistema de produção de acerola em larga escala, sob manejo orgânico, e uma área sob cultivo convencional de cenoura e beterraba em rotação com milho, pertencentes à Fazenda Amway Nutrilite do Brasil e à Associação de Horticultores do Pivot Central, respectivamente, ambas localizadas na região da Chapada da Ibiapaba, Ceará. Selecionou-se, também, uma área de pastagem localizada no interior da primeira propriedade amostrada, bem como áreas sob mata nativa, próximas às áreas de cultivo. Amostras de um Neossolo Quartzarênico foram coletadas nas profundidades de 0-5 e 5-15 cm e foram determinados os teores de C orgânico total, de C e N microbiano (Cmic e Nmic e da matéria orgânica leve (Cmol e Nmol, além do C mineralizável obtido por respirometria. O acúmulo médio nos estoques de Nmic nas áreas sob manejo orgânico em relação à mata nativa foi de 11,7 kg ha-1, o que representou um incremento de 585 % de Nmic nas áreas de cultivo. Já na pastagem, ocorreu acúmulo de 211 kg ha-1 no estoque de Cmic em relação à mata nativa em subsuperfície, representando um incremento de 514,6 %. Por outro lado, os estoques de Cmic no cultivo convencional sofreram reduções de 59 e 53 %, nas camadas de 0-5 e de 5-15 cm, respectivamente, em relação à mata nativa. Os estoques de Cmol obtidos nas linhas de cultivo nos sistemas orgânicos apresentaram incremento de 106 %, na camada de 0-5 cm, em relação à mata; no sistema convencional, porém, constatou-se uma redução em 31 % no estoque de Cmol na camada

  6. Caracterização de crianças e adolescentes atendidos por maus tratos em um hospital de emergência no município de Fortaleza-CE Characterization of maltreated children and adolescents taken into a paediatric emergency health care service in Fortaleza-CE-Brazil

    OpenAIRE

    Arcelina Maria da Silva; Luiza Jane Eyre de Souza Vieira

    2001-01-01

    O estudo teve como objetivo caracterizar o perfil da criança e adolescente maltratados e atendidos em um hospital de emergência, no Município de Fortaleza, Ceará. Utilizou-se a pesquisa documental retrospectiva com análise dos formulários da Comissão de Maus Tratos à Infância e Adolescência. Os resultados revelaram que o sexo masculino e a faixa etária de 1 a 5 anos foram os mais atingidos; o principal agressor é o pai biológico e os tipos de violência mais freqüentes foram o hematoma, o abus...

  7. Caracterização de crianças e adolescentes atendidos por maus tratos em um hospital de emergência no município de Fortaleza-CE Characterization of maltreated children and adolescents taken into a paediatric emergency health care service in Fortaleza-CE-Brazil

    Directory of Open Access Journals (Sweden)

    Arcelina Maria da Silva

    2001-03-01

    Full Text Available O estudo teve como objetivo caracterizar o perfil da criança e adolescente maltratados e atendidos em um hospital de emergência, no Município de Fortaleza, Ceará. Utilizou-se a pesquisa documental retrospectiva com análise dos formulários da Comissão de Maus Tratos à Infância e Adolescência. Os resultados revelaram que o sexo masculino e a faixa etária de 1 a 5 anos foram os mais atingidos; o principal agressor é o pai biológico e os tipos de violência mais freqüentes foram o hematoma, o abuso sexual e as lesões por objetos cortantes. Conclui-se que o tema requer estudos aprofundados que modifiquem o ambiente em que a criança, adolescente e famílias estão inseridos.This study aimed to characterise the profile of the child and the adolescent who were maltreated and taken into paediatric emergency care in a hospital, in Fortaleza, Ceará. It was used a documented retrospective evaluation. The results showed that the children in the age group of 1-5 years were the most victimised as well as the children of the male sex. The main perpetrator was a biological father and the most frequent kind of violence were hematomas, sexual abuse and wounds by slashing objects. In conclusion, this subject needs to be more investigated for providing changes within the' environment where a child, adolescent and families were inserted.

  8. Nioboaeschynite-(Ce, Ce(NbTiO6

    Directory of Open Access Journals (Sweden)

    Shaunna M. Morrison

    2012-08-01

    Full Text Available Nioboaeschynite-(Ce, ideally Ce(NbTiO6 [cerium(III niobium(V titanium(IV hexaoxide; refined formula of the natural sample is Ca0.25Ce0.79(Nb1.14Ti0.86O6], belongs to the aeschynite mineral group which is characterized by the general formula AB2(O,OH6, where eight-coordinated A is a rare earth element, Ca, Th or Fe, and six-coordinated B is Ti, Nb, Ta or W. The general structural feature of nioboaeschynite-(Ce resembles that of the other members of the aeschynite group. It is characterized by edge-sharing dimers of [(Nb,TiO6] octahedra which share corners to form a three-dimensional framework, with the A sites located in channels parallel to the b axis. The average A—O and B—O bond lengths in nioboaeschynite-(Ce are 2.471 and 1.993 Å, respectively. Moreover, another eight-coordinated site, designated as the C site, is also located in the channels and is partially occupied by A-type cations. Additionally, the refinement revealed a splitting of the A site, with Ca displaced slightly from Ce (0.266 Å apart, presumably resulting from the crystal-chemical differences between the Ce3+ and Ca2+ cations.

  9. Gestão do desempenho humano: um estudo de caso em um Hospital Geral de Fortaleza (CE Administration of the human acting: a case study in a General Hospital of Fortaleza, Ceará State

    Directory of Open Access Journals (Sweden)

    Maria de Fátima Marrocos Fontenele

    2010-06-01

    Full Text Available A temática deste trabalho apresenta questões sobre a prática da avaliação de desempenho funcional em uma organização pública de saúde. Este eixo de análise ganha destaque a partir das dificuldades de desenvolvimento de sistemas de avaliação com alianças entre políticas de concessão de incentivos financeiros, em um contexto cultural peculiar. Nesse sentido, é necessário admitir os limites dessa ferramenta gerencial. A partir de uma pesquisa qualitativa, utilizou-se um roteiro semiestruturado de perguntas aplicado aos servidores de um hospital geral público do Estado do Ceará. Obteve-se a caracterização do sistema de avaliação de desempenho utilizado pela instituição, podendo-se verificar sua adequação aos modelos propostos na literatura e a pertinência de seus propósitos com as percepções e expectativas dos servidores pesquisados.The thematic of this work presents questions on the practice of the Evaluation of functional performance in an organization of public health. This axle of analysis gains importance from the difficulties of developing evaluation systems with alliances between policies of concession of financial incentives, in a specific cultural context. In this direction, it is necessary to admit the limits of this management tool. From a qualitative research, a semi-structured questionnaire was applied to the staff (public servers of a public general hospital of Ceará State. It was observed the characterization of the performance evaluation system used in the institution, being able to verify its adequacy to the models proposed in the literature and the relevancy of its intentions with the perceptions and expectations of the searched servers.

  10. Hanseníase no município de Fortaleza, CE, Brasil: aspectos epidemiológicos e operacionais em menores de 15 anos (1995-2006 La Lepra en el municipio de Fortaleza, CE, Brasil: aspectos epidemiológicos y operacionales en menores de 15 años (1995-2006 Hansen's Disease in the municipality of Fortaleza, CE, Brazil: epidemiological and operational aspects in children under 15-years-old (1995-2006

    Directory of Open Access Journals (Sweden)

    Carlos Henrique Morais de Alencar

    2008-11-01

    Full Text Available Estudo transversal que objetiva analisar a ocorrência de casos de hanseníase em menores de 15 anos de idade residentes no Município de Fortaleza e notificados no SINAN. Os indicadores epidemiológicos nesta população mostram hiperendemicidade. Operacionalmente observa-se a manutenção da concentração de atendimento em algumas unidades de referência, apesar de alguns avanços. Diagnóstico tardio, elevado grau de incapacidade no diagnóstico e baixo grau de avaliação de contatos registrados revelam a fragilidade das ações de controle. Ressalta-se a possibilidade de erro diagnóstico frente às características da infecção nesta população. A ocorrência de casos de hanseníase nesta população representa um indicador epidemiológico de grande relevância e sua análise amplia a discussão sobre problemas operacionais na rede de serviços de saúde.Estudio transversal con el objetivo de analizar las ocurrencias de los casos de lepra en menores de 15 años de edad sitiados en la ciudad de Fortaleza y enterados en el SINAN. Los indicadores epidémicos en ésta población se presentaron hiperendémicos. En la operacinalización, se observa el mantenimiento de la concentración de atención en algunas unidades recomendables, a pesar de algunos avances. Diagnósticos muy tardes, gran grado de incapacidad en el diagnóstico y bajo grado de evaluación de contactos registrados, muestran la fragilidad de las acciones de control. Se resalta así la posibilidad de error de diagnóstico delante de las características de la infección en ésta población. La ocurrencia de casos de lepra en ésta población representa un indicador epidémico de gran importancia y su análisis amplia la discusión sobre los problemas operacionales en la red de servicios públicos.This is a sectional study that aims to analyze the occurrence of Hansen's disease cases in 15 year-old minors in the Municipality of Fortaleza and notified in SINAN. The

  11. Temporal analysis of the connectivity and potential transport capacity of sediments in semiarid meso-basin, CE, Brazil. = Análise temporal da conectividade e da capacidade de transporte potencial de sedimentos em meso-bacia semiárida, CE, Brasil.

    Directory of Open Access Journals (Sweden)

    José Wellington Batista Lopes

    2013-08-01

    Full Text Available The transfer of energy and matter between two topographic units comprise the connectivity process. The identification of the connectivity patterns in the catchments allow to represent the linking degree between sediment producing areas and network drainage. The aim of this study was to evaluate spatial and temporal connectivity and estimate the potential capacity of sediment transport on a meso-semiarid Basin. The study area comprises the Representative Madalena Basin (RMB with area 124 km², located at federal state from Ceara, Brazil. The assessing the connectivity was done by using the quantitative index. The determination of peak discharge was by the method NRCS (Natural Resouces Conservation Service and the transport capacity (CT, t ha-1 yr-1 was calculated by the method of Morgan (2001. The results showed that: the connectivity potential index was not linearity, but a possible spatial distribution pattern of alternating between producing and receiving areas. The use and occupation of land is determinant in the spatial variation of peak flows; transportation capacity concerns associated with potential connectivity provides best estimates of erosion in the basin; in both models used, the use and occupation of soil was crucial in the results. = A transferência de energia e matéria entre duas unidades topográficas compreende o processo deconectividade. A identificação dos padrões de conectividade em uma bacia hidrográfica permite representar o grau de ligação entre áreas produtoras de sedimentos e a rede de drenagem. Objetivou-se com esta pesquisa analisar a conectividade espaço-temporal e estimar a capacidade potencial de transporte de sedimentos em uma meso-baciasemiárida. A área foco do estudo compreende a Bacia Representativa de Madalena (BRM com área de 124 km², localizada no Estado do Ceará, Brasil. Foram avaliadas as seguintes variáveis: conectividade, o pico de descarga e a capacidade de transporte de escoamento da

  12. Inovação educacional em pequeno município: o caso Fundação Casa Grande (Nova Olinda, CE, Brasil Educational innovation in small towns: the case of 'Fundação Casa Grande' (Nova Olinda, CE, Brazil

    Directory of Open Access Journals (Sweden)

    Elie Ghanem

    2012-09-01

    Full Text Available Este artigo apresenta os resultados de um estudo de caso de inovação educacional na atuação da Organização Não Governamental Fundação Casa Grande - Memorial do Homem Kariri junto a crianças e jovens do município de Nova Olinda, CE, Brasil. O principal problema da pesquisa que este artigo visa apresentar é: que fatores se conjugam na geração de ações de inovação educacional? A hipótese examinada pela pesquisa foi a de que fatores salientes que se conjugam na geração de ações de inovação são o tempo de experiência profissional de educadores(as, a estabilidade de sua equipe, o nível de qualificação e a atuação mobilizadora de líderes da Organização. São descritos os objetivos e características da atuação da Organização e são apontadas as características de líderes, agentes e equipes. Conclui que a hipótese levantada foi confirmada.This article presents the results of an educational innovation case study on the 'Fundação Casa Grande - Memorial do Homem Kariri' Non-governmental Organization's operation with children and youngsters in Nova Olinda, State of Ceara, Brazil. The main matter of this research is: What factors are conjugated at the genesis of educacional innovation actions? The study examines the hypothesis that the proeminent factors conjugated in educational innovation generation are: length of educator's professional experience, team's stability, NGO leaders' qualification level, and mobilizing action. The NGO's objectives and operation characteristics are described. Characteristics of leaders, education agents and teams are presented. It was possible to conclude that the proposed hypothesis was confirmed.

  13. Ce que soigner veut dire

    OpenAIRE

    Mol, Annemarie

    2013-01-01

    Qu'est-ce que bien soigner? Dans ce livre provoquant et original, Annemarie Mol montre que ce n'est pas, comme on l'a beaucoup dit, laisser les patients choisir. À partir de l'exemple des personnes atteintes de diabète, l'auteur propose une nouvelle manière de prendre soin des personnes, qui ne les transforme pas en citoyens ou en consommateurs, mais qui les reconnaît comme corps et âmes souffrants, comme individus investis dans leur propre prise en charge, comme membres de collectifs multipl...

  14. Avaliação construtivista, sob uma abordagem integradora e intersetorial, das ações do Projeto Disque Idoso em Sobral (CE, Brasil Constructivist evaluation, under an integrating and intersectoral approach, of actions of the Disque Idoso Project in Sobral (CE, Brazil

    Directory of Open Access Journals (Sweden)

    Cibelly Aliny Siqueira Lima Freitas

    2010-09-01

    Full Text Available O envelhecimento populacional no Brasil e no mundo é motivo de inquietação epidemiológica. Assim, a violência contra o idoso tem sido considerada problema de saúde pública. Este estudo tem como contexto a necessidade de saúde dos idosos que sofrem violência, objetivando avaliar construtivistamente o Projeto Disque Idoso em Sobral (Ceará. Utilizamos o Método de Avaliação Construtivista de Furtado, que proporciona a introdução de práticas de avaliação participativa. Tentando alcançar tal perspectiva, nos guiamos pelos caminhos da abordagem integradora (inter, multi e transdisciplinar e intersetorial. Realizamos os grupos focais com representantes dos setores da saúde, assistência social, justiça e idosos, tanto beneficiados pelo projeto como outros que contribuem para seu desenvolvimento. Ao interagirmos com os profissionais que atuam na sede do projeto, compreendemos que há receio em divulgar seu trabalho, pois não há estrutura para ampliar o atendimento. O grupo acredita que a eficácia de suas ações é limitada pela falta de transporte fixo e outros profissionais qualificados. Para os profissionais da rede social de apoio, o projeto deve buscar atuação intersetorial, uma vez que pretende atingir assistência integral. Para os idosos, o projeto é bastante válido e precisa se consolidar no município.The population aging in Brazil and in the world is a reason for an epidemic inquietude. So, the violence against senior people has been considered a problem of public health. This study takes as context the health need of seniors that suffer of violence, aiming to evaluate in a constructive way the Disque Idoso Project in Sobral (Ceará, Brazil. We used Furtado's Constructivist Method of Evaluation, which provides practices of participative evaluation. Trying to reach such perspective, we are guided by paths of the integrative approach (inter, multi and transdisciplinary and intersectoral. We accomplished the focal

  15. Signature splitting in 129Ce

    Institute of Scientific and Technical Information of China (English)

    LIU Ying; WU Xiao-Guang; ZHU Li-Hua; LI Guang-Sheng; HE Chuang-Ye; LI Xue-Qin; PAN Bo; HAO Xin; LI Li-Hua; WANG Zhi-Min; LI Zhong-Yu; XU Qiang

    2009-01-01

    The high spin states of 129Ce have been populated via heavy-ion fusion evaporation reaction 96Mo (37C1, 1p3n) 129Ce. The γ-γ coincidence and intensity balance used to measure the B(M1; I→I-1)/B(E2; I→I-2) (the probability ratio of the dipole and quadrupole transition) in v7/2[523] rotational band of 129Ce. And the energy splitting (Δe') has been got through the experimental Routhians. The lifetimes and quadrupole moments Qt have been extracted from the lineshape analyses using DSAM. The deformation of the v7/2[523] rotational band of 129Ce was extracted from the Qt and moment of inertia JRR.

  16. Qualidade da atenção ao pré-natal na Estratégia Saúde da Família em Sobral, Ceará Calidad de la atención en el pre-natal en la Estrategia Salud de Familia en Sobral, CE, Brasil Quality of pre-natal care in Family Health Strategy in Sobral, CE, Brazil

    Directory of Open Access Journals (Sweden)

    Francisco Rosemiro Guimarães Ximenes Neto

    2008-10-01

    Full Text Available Diante das políticas públicas que envolvem a qualidade da atenção ao pré-natal, este estudo teve como objetivo avaliar a qualidade da atenção ao pré-natal nos territórios da Estratégia Saúde da Família, do município de Sobral, à luz do referencial teórico de Avedis Donabedian. Trata-se de um estudo de caráter descritivo-exploratório, desenvolvido em Centros de Saúde da Família de Sobral, Ceará. Dos quatorze Centros de Saúde investigados, quatro se mostraram com indicadores adequados para o pré-natal. Porém, ainda que existam inadequações na estrutura física, não existem impedimentos para que se ofereça um atendimento de qualidade haja vista que o processo e os resultados também interferem na qualidade da assistência.Frente a las políticas públicas que impliquen la calidad de la atención a la salud prenatal, el estudio tiene como objetivo: evaluar la calidad de la atención prenatal a los territorios en la Estrategia de Salud de la Familia de la ciudad de Sobral, a la luz del referencial teórico de AVEDIS Donabedian. Se trata de un estudio exploratorio de carácter descriptivo, desarrollado por los Centros de Salud Familiar de Sobral - Ceará. De los catorce Centros de Salud investigaron, cuatro fueron con los indicadores apropiados para la atención prenatal. Pero a pesar de que hay deficiencias en la estructura física, no hay impedimentos a fin de proporcionar una calidad de la atención hay una opinión de que el proceso y los resultados también interferir con la calidad de la atención.Face to public policies involving the quality of care for prenatal, the study aims to: assess the quality of prenatal care to the territories in the Family Health Strategy of the city of Sobral in the light of theoretical reference of Avedis Donabedian. This is a descriptive- exploratory study, developed by Family Health Units of Sobral, CE, Brazil. Of the fourteen Centers Health investigated, four were with appropriate

  17. Lattice dynamics of γ--Ce

    International Nuclear Information System (INIS)

    The phonon and magnetic measurements described in the thesis produced the following significant results concerning the lattice dynamical and magnetic properties of γ-Ce. The phonon spectrum is relatively soft, which is consistent with results obtained for CeSn3. The L [110] and T [111] branches of the dispersion curve are anomalous. The C11 and C44 elastic constants are quite close in value. No discrete magnetic excitations were observed. The magnetic scattering is qualitatively similar to the results from Ce0.74Th0.26, however, GAMMA/sub Ce/ less than GAMMA/sub Ce-Th/. The various lattice dynamical and magnetic similarities among γ-Ce, CeSn3, and Ce0.74Th0.26 are mixed valence compounds. Therefore, a complete theoretical description of the observed properties of Ce and its compounds may provide a basis for understanding a whole class of mixed valence materials

  18. Electrochemical aspects of Ce+3 / Ce system in Flinak

    International Nuclear Information System (INIS)

    The voltammetric electrodeposition of cerium has been studied on three types of substrates - Ag, W and vitreous Carbon with the aim of know the mechanisms of the process. The Flinak - Ce F3 melt was used, with temperature range of 500-850O C. No alkaline metals co deposition was observed. (author)

  19. Collective excitations in 132Ce

    International Nuclear Information System (INIS)

    The structure of normally deformed states (β2∼0.2) in 132Ce has been investigated using EUROGAM2. Eight ΔI=2 bands and three ΔI=1 bands have been identified up to spin 40. The results are interpreted with the aid of Woods-Saxon cranking calculations which suggest a variety of triaxial shapes stabilized by specific active quasiparticle orbitals. (authors)

  20. Identification of levels in neutron-rich 145Ce and 147Ce nuclei

    International Nuclear Information System (INIS)

    High-spin structures in the neutron-rich nuclei 145Ce and 147Ce produced in the spontaneous fission of 252Cf have been investigated by prompt γ-ray spectroscopy. A collective band structure in 145Ce is identified. Several sidebands along with the new high-spin states in 147Ce are also identified. Particle-plus-rotor model calculations indicate that the yrast bands in 145Ce and 147Ce most probably originate from coupling of the νi13/2 orbital to the ground states of 144Ce and 146Ce. The ground state configurations of 145,147Ce are (νh9/2+νf7/2) and νh9/2, respectively. (c) 1999 The American Physical Society

  1. Energy levels of the Ce activator relative to the YAP(Ce) scintillator host

    International Nuclear Information System (INIS)

    The electronic structure of the cerium-activated yttrium aluminum perovskite [YAP(Ce)] scintillator has been studied by core level x-ray spectroscopy and first-principles calculations. X-ray absorption and emission spectra at the oxygen K-edge of YAP(Ce) and CeO2 have been measured and compared with the calculated partial density of states. With the known band gap of CeO2, the measured oxygen K-edge absorption and emission spectra are used to construct a fixed relation between the valence and conduction bands of YAP and CeO2. This allows us to determine the fundamental band gap of YAP to be 8.1 ± 0.3 eV. A comparison between the cerium M4,5-edges x-ray absorption spectra of the YAP(Ce) and Ce model compounds (CeO2, CeF3, and Ce foils) then shows that the Ce activator is in the desired Ce3+, with a small fraction of Ce4+ due to oxidization at the surface. Finally, we determine that the ground state 4f1 energy level of the Ce3+ activator lies 1.8 ± 0.5 eV above the top of the valence band of the host YAP. (paper)

  2. Photoelectron spectra of CeO{sup −} and Ce(OH){sub 2}{sup −}

    Energy Technology Data Exchange (ETDEWEB)

    Ray, Manisha; Felton, Jeremy A.; Kafader, Jared O.; Topolski, Josey E.; Jarrold, Caroline Chick, E-mail: cjarrold@indiana.edu [Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405 (United States)

    2015-02-14

    The photoelectron spectrum of CeO{sup −} exhibits what appears to be a single predominant electronic transition over an energy range in which numerous close-lying electronic states of CeO neutral are well known. The photoelectron spectrum of Ce(OH){sub 2}{sup −}, a molecule in which the Ce atom shares the same formal oxidation state as the Ce atom in CeO{sup −}, also exhibits what appears to be a single transition. From the spectra, the adiabatic electron affinities of CeO and Ce(OH){sub 2} are determined to be 0.936 ± 0.007 eV and 0.69 ± 0.03 eV, respectively. From the electron affinity of CeO, the CeO{sup −} bond dissociation energy was determined to be 7.7 eV, 0.5 eV lower than the neutral bond dissociation energy. The ground state orbital occupancies of both CeO{sup −} and Ce(OH){sub 2}{sup −} are calculated to have 4f 6s{sup 2} Ce{sup +} superconfigurations, with open-shell states having 4f5d6s superconfiguration predicted to be over 1 eV higher in energy. Low-intensity transitions observed at higher electron binding energies in the spectrum of CeO{sup −} are tentatively assigned to the {sup 1}Σ{sup +} (Ω = 0) state of CeO with the Ce{sup +2}⍰6s{sup 2} superconfiguration.

  3. Phytochemical and Biological Studies of <em>Agave em>attenuata>

    OpenAIRE

    Vincenzo De Feo; Muhammad Riaz; Nasir Rasool; Muhammad Zubair; Komal Rizwan; Muhammad Zia-Ul-Haq

    2012-01-01

    The present study was conducted to examine various biological activities of a methanol extract of <em>Agave attenuataem> leaves. GC-MS analysis of the <em>n>-hexane fraction from the extract revealed the presence of 31 compounds, with mono-2-ethylhexyl phthalate (11.37%), 1,2-benzenedicarboxylic acid (6.33%), <em>n>-docosane (6.30%) and eicosane (6.02%) as the major components. The leaves contained appreciable levels of total phenolic contents (10...

  4. Lifetimes of Excited Levels in 131Ce

    Institute of Scientific and Technical Information of China (English)

    LI Guang-Sheng; LI Xian-Feng; WEN Li-Jun; ZHENG Yong-Nan; ZHENG Yong; LIU Yun-Zuo; YUAN Guan-Jun; YANG Chun-Xiang; MENG Rui; ZHU Li-Hua; ZHANG Zhen-Long; WANG Yue; WANG Zhi-Min; WEN Shu-Xian; LU Jing-Bin; ZHAO Guang-Yi

    2004-01-01

    @@ The fusion-evaporation reaction 116Sn (1gF, p3n) 131 Ce at projectile energy of 95 MeV is used to populate high spin states in 131 Ce. The de-exciting γ-rays are detected in γ-γ coincidence measurement with Compton-suppressed BGO-HPGe detectors. Level lifetimes of 131 Ce were determined by using the Doppler shift attenuation method.The experimental results indicate that collectivity of 131 Ce is reduced relative to that of 130 Ce and it follows that deformation decreases with increase of the neutron number on the basis of systematic comparison of transition quadrupole moments for the light cerium isotopes.

  5. Temperature dependence of the scintillation properties of Ce:GSO and Ce:GSOZ

    Energy Technology Data Exchange (ETDEWEB)

    Kurosawa, Shunsuke, E-mail: kurosawa@imr.tohoku.ac.jp [Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577 (Japan); Sugiyama, Makoto [Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577 (Japan); Yanagida, Takayuki [New Industry Creation Hatchery Center (NICHe), 6-6-10 Aoba Aramaki, Aoba-ku, Sendai, Miyagi 980-8579 (Japan); Yokota, Yuui [Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577 (Japan); Yoshikawa, Akira [Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577 (Japan); New Industry Creation Hatchery Center (NICHe), 6-6-10 Aoba Aramaki, Aoba-ku, Sendai, Miyagi 980-8579 (Japan)

    2012-10-21

    The light output and decay times of Ce:GSO and Ce:GSOZ scintillators depend on Ce concentration and temperature. We investigated the temperature dependence of the light output and the decay time for Ce:GSO and Ce:GSOZ doped with 0.3 (only GSO), 0.5, 1.0, and 1.5 mol% Ce. These samples were measured with a ruggedized photomultiplier (PMT) (Hamamatsu R6877A) at 175 Degree-Sign C (in the thermostat chamber). Up to 100 Degree-Sign C, the relative light output of all of the samples remained within 10% after correcting the PMT gain, which depends on the temperature. The decay times of the GSO and GSOZ samples with the identical Ce concentrations were equal. Moreover, the quenching energy values for all the samples were equivalent.

  6. Temperature dependence of the scintillation properties of Ce:GSO and Ce:GSOZ

    International Nuclear Information System (INIS)

    The light output and decay times of Ce:GSO and Ce:GSOZ scintillators depend on Ce concentration and temperature. We investigated the temperature dependence of the light output and the decay time for Ce:GSO and Ce:GSOZ doped with 0.3 (only GSO), 0.5, 1.0, and 1.5 mol% Ce. These samples were measured with a ruggedized photomultiplier (PMT) (Hamamatsu R6877A) at 175 °C (in the thermostat chamber). Up to 100 °C, the relative light output of all of the samples remained within 10% after correcting the PMT gain, which depends on the temperature. The decay times of the GSO and GSOZ samples with the identical Ce concentrations were equal. Moreover, the quenching energy values for all the samples were equivalent.

  7. Unstable magnetic moments in Ce compounds

    International Nuclear Information System (INIS)

    The problems which are connected with the appearance or disappearance of local moments in metals are well reflected in the magnetic behaviour of Ce intermetallic compounds. This work describes experiments on two Ce compounds which are typical examples of unstable moment systems. The first of these is CeAl2 which at low temperatures, shows coexistence of antiferromagnetic order and the Kondo effect. Measurements are presented of the magnetization and the susceptibility in different magnetic field and temperature regions. An analysis of these measurements, using a model for the crystal field effects, shows the agreement between the measurements and the calculations to be reasonably good for CeAl2, but this agreement becomes worse upon decreasing Ce concentration. A phenomenological description of the observations is given. The second compound reported on is CeCu2Si2, the first 'heavy-fermion' superconductor to be investigated. The superconducting state is possibly formed by the quasi-particles of a non-magnetic many body singlet state, and not simply by the (sd) conduction electrons. This being a novel phenomenon, a number of experiments were performed to test this picture and to obtain a detailed description of the behaviour of CeCu2Si2. Measurements of the Meissner volume, confirmed the superconductivity to be intrinsic. (Auth.)

  8. Cost objective PLM and CE

    CERN Document Server

    Perry, Nicolas

    2010-01-01

    Concurrent engineering taking into account product life-cycle factors seems to be one of the industrial challenges of the next years. Cost estimation and management are two main strategic tasks that imply the possibility of managing costs at the earliest stages of product development. This is why it is indispensable to let people from economics and from industrial engineering collaborates in order to find the best solution for enterprise progress for economical factors mastering. The objective of this paper is to present who we try to adapt costing methods in a PLM and CE point of view to the new industrial context and configuration in order to give pertinent decision aid for product and process choices. A very important factor is related to cost management problems when developing new products. A case study is introduced that presents how product development actors have referenced elements to product life-cycle costs and impacts, how they have an idea bout economical indicators when taking decisions during t...

  9. Hydrogenation of the intermediate valence ternary stannides CeRhSn and CeIrSn

    OpenAIRE

    Chevalier, Bernard; Sebastian, C. P.; Pöttgen, Rainer

    2006-01-01

    CeRhSn and CeIrSn were synthesized from the elements via arc-melting. A single crystal from the CeIrSn sample was investigated on the basis of X-ray diffractometer data: ZrNiAl type, P2m, a=743.8(2), c=407.58(7) pm, wR2=0.0308, 352 F2 values and 14 variable parameters. An important structural feature of CeIrSn are relatively short Cesingle bondIr distances (4×303 and 1×308 pm). Hydrogenation of these ternary stannides leads to the formation of the new hydrides CeRhSnH0.8 and CeIrSnH0.7 which ...

  10. White and colored marbles from the “G. Carreca” and “Ce.Ri.co” barraks at Rome I marmi bianchi e colorati dalle caserme “G. Carreca” e “Ce.Ri.co” a Roma

    Directory of Open Access Journals (Sweden)

    Marco Viglietti

    2011-03-01

    Full Text Available

    Questo lavoro si inserisce nell’ambito delle indagini archeologiche compiute tra il 2002 e il 2008 nell’area delle caserme “G. Carreca” e “Ce.Ri.co.”, in via Labicana a Roma. Ad una prima strutturazione dell’area di età domizianea, seguono fasi di vita di età antonina e severiana, prima dell’ultima, grande fase edificatoria riferibile alla seconda metà del IV - V secolo. La nostra indagine si appunta sul consistente deposito di marmi da <em>opus sectileem> pavimentale e parietale. Specchio di un’elevata committenza, costituisce un campionario delle forme decorative in uso a Roma tra il I e il IV - V secolo. 

    This work develops from the archaeological researches carried out between 2002 and 2008 in Rome, via Labicana, in the area of “G. Carreca” and “Ce.Ri.co.” barracks. These the phases recognized: late Flavian, Antonine and Severiane, before the latest in the second half of IV/V cent. A.D. The survey focus on a considerable marble’s deposit in the kind of pavimental and parietal <em>opus> <em>sectile>. It’s a mark of an elevated customer and it represents a decorative shapes set of samples in use at Rome between I and IV-V cent. A.D.

  11. Radiation streaming with SAM-CE

    International Nuclear Information System (INIS)

    The SAM-CE Monte Carlo code has been employed to calculate doses, due to neutron streaming, on the operating floor and other locations of the Millstone Unit II Nuclear Power Facility. Calculated results were compared against measured doses

  12. Structural and magnetic properties of Ce/Fe and Ce/FeCoV multilayers

    Energy Technology Data Exchange (ETDEWEB)

    Tixier, S.; Boeni, P. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Mannix, D.; Stirling, W.G. [Liverpool Univ. (United Kingdom); Lander, G.H.

    1997-09-01

    Ce/Fe and Ce/FeCoV multilayers have been grown by magnetron sputtering. The interfaces are well defined and the layers are crystalline down to an individual layer thickness of 20 A. Ce/FeCoV multilayers show sharper interfaces than Ce/Fe but some loss of crystallinity is observed. Hysteresis loops obtained by SQUID show different behaviour of the bulk magnetisation as a function of the layer thickness. Fe moments are found by Moessbauer spectroscopy to be perpendicular to the interfaces for multilayers with small periodicity. (author) 2 figs., 2 refs.

  13. Magnetic and transport properties of CePdAs and CePdSb

    International Nuclear Information System (INIS)

    The results of measurements of electrical resistivity ρ, magnetic susceptibility χ, magnetization M and specific heat C are reported on single-crystalline samples of CePdAs and CePdSb. As for CePdAs, ρ(T) perpendicular to the c-axis behaves like a metal and a sharp drop appears around 4 K corresponding to the magnetic transition. But ρ(T) parallel to the c-axis shows a maximum at about 10 K and semiconducting behavior at high temperature. ρ(T) perpendicular to the c-axis on CePdSb shows the same metallic behavior as in the case of CePdAs. The strong aniosotropy in ρ(T) suggests that CePdAs and CePdSb are better characterized as quasi-two-dimensional electrical conductors. This anisotropy is also manifested in χ and M. χ(T) and M(H) along the c-axis of CePdAs and CePdSb exhibits antiferromagnetic ordering at 4 and 17 K, respectively. But χ(T) along the a-axis increases, with decreasing temperature following Curie-Weiss-like behavior of a ferromagnet. (orig.)

  14. Preceptoria de território, novas práticas e saberes na estratégia de educação permanente em saúde da família: o estudo do caso de Sobral, CE Preceptorship of territory, new practices and knowledge in the strategy of continuing education in family health strategy: the case study of Sobral, Ceara, Brazil

    Directory of Open Access Journals (Sweden)

    Rosani Pagani

    2012-05-01

    Full Text Available O presente trabalho pretende apresentar um novo ator no Sistema Único de Saúde - o preceptor de território - bem como discutir sua atuação. Com a implantação da Estratégia Saúde da Família, bastante se tem discutido sobre o desafio de formar profissionais para atuarem neste modelo através de educação permanente em saúde. Nesse processo, o município de Sobral, CE, criou em 1999 a residência multiprofissional e a preceptoria de território; em 2001, a Escola de Formação em Saúde da Família Visconde de Sabóia. Este estudo teve como objetivos analisar a implantação e a atuação da preceptoria de território, descrevendo o processo de trabalho dos preceptores e identificando suas competências; além disso, descreveu-se o processo de educação permanente desenvolvido na Estratégia de Saúde da Família em Sobral. Utilizou-se uma abordagem qualitativa do tipo estudo de caso, com os seguintes instrumentos: entrevistas, questionários e grupo focal. Para a organização os dados foram analisados através da técnica do Discurso do Sujeito Coletivo (DSC. Entre os achados do estudo, identifica-se o preceptor de território como um profissional que atua diretamente com os residentes nos territórios das equipes da estratégia de saúde da família, destacando-se por suas amplas competências. Entre estas, podem ser mencionados conhecimentos conceituais nos campos da saúde coletiva e das relações humanas, bem como conhecimento e desenvoltura na utilização de métodos de ensino (problematização, educação permanente em saúde e educação popular. Deve também ser capaz de desenvolver relações harmônicas e de participação. O debate vem auxiliando o preceptor de território de Sobral a estabelecer seu papel e consolidar sua função de educador na construção do SUS.This paper aims to present a new actor in the Health's Unique System of Brazil (SUS, the preceptor of territory, and discuss his performance. The

  15. CeRh3B2: A ferromagnet with anomalously large Ce 5d spin and orbital magnetic moments

    International Nuclear Information System (INIS)

    We report a high-energy magnetic-Compton-scattering study performed on the ferromagnet CeRh3B2. This technique solely measures the electron spin magnetic moments. In contrast to a number of Ce intermetallics with nonmagnetic elements, the Ce 5d spin moment is found to be large and parallel to the Ce 4f spin moment. Therefore the Kondo effect does not play a key role for CeRh3B2. The inferred large Ce 5d orbital magnetic moment is a signature of the strong spin-orbit interaction for the Ce 5d band. copyright 1998 The American Physical Society

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

    International Nuclear Information System (INIS)

    Neutron diffraction experiments on the Al3Ce and Al11Ce3 compounds have been performed on the multidetector of the I.L.L. high flux reactor. No magnetic structure has been detected on the Al3Ce compound down to 20 mK. This confirms the non magnetic ground state of Al3Ce. For Al11Ce3, 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

  17. Variation of education continuation. What you need to know about CE classes.

    Science.gov (United States)

    Friese, Greg

    2013-11-01

    Finally, always let training objectives drive the training methodology. An objective to review a pain management protocol is easily accomplished by acknowledging receipt and reading of an electronic document. An objective to assess and appropriately treat a pediatric patient with pain secondary to musculoskeletal trauma is better accomplished through case review and simulation. Opportunities for online CE are continuing to expand. Smartphones and tablets are encouraging educators to develop training content that has increasing interactivity and immediate feedback. Massive Online Open Courses are the newest frontier on the online CE landscape. Keep an open mind about how, when, and where EMT and paramedic continuing education can be delivered and completed. The EMS classroom is no longer bounded by brick-and-mortar walls and the weekday availability of instructors. PMID:24475622

  18. Diversidade de Scarabaeinae (Coleoptera: Scarabaeidae) no Parque Botânico do Ceará, Caucaia - CE, Brasil.

    OpenAIRE

    Lima, Maria Goretti Araújo; Silva, Rodolpho Peixoto de Almeida; Sousa, Maria Danielle Feitosa de; Costa, Ewerton Marinho

    2013-01-01

    Objetivou-se com o presente trabalho realizar levantamento e análise da riqueza, abundância, equitabilidade e diversidade das espécies de Scarabaeinae em dois ambientes, Mata Ciliar de Carnaúba e Mata de Tabuleiro, no Parque Botânico do Ceará, Caucaia – CE, Brasil. As coletas foram realizadas mensalmente durante o período de março a novembro de 2008. Para captura dos escarabeídeos foram utilizadas 48 armadilhas de solo tipo “Pitfall”, iscadas com fezes humanas, sendo 24 armadilhas em cada ...

  19. Superconductivity in CeCo2 nanoparticles

    International Nuclear Information System (INIS)

    Both Ce and Co are essentially nonmagnetic in Pauli-paramagnetic CeCo2, which undergoes a superconducting transition near 1K. When made into 58-A nanoparticles, the compound becomes paramagnetic. Meanwhile, based on heat capacity measurements, the nanoparticles remain to be nonsuperconducting down to 0.4K but exhibit a low-temperature Kondo anomaly with C/T∼ 350mJ/molK2 at 0.4K. Such intriguing effects are consequences of the competition between superconducting gap and electronic spectrum's mean level spacing

  20. Laser altimeter of CE-1 payloads system

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The design and operation of the Laser Altimeter of CE-1 Payloads System are presented in this paper.The paper includes the design of the system and spacecraft-level laser,the description of the emitting-system and receiving system,and the testing of the laser altimeter.The CE-1 laser altimeter is the first Chinese deep-space probe using a laser.It has one beam and operates at 1 Hz,with a nominal accuracy of 5 m.The laser altimeter has operated successfully in lunar orbit since November 28,2007.It has obtained 9120 thousand data values about the lunar altitude.

  1. Metamagnetism in Ce(Ga,Al)2

    Indian Academy of Sciences (India)

    K G Suresh; S Radha; A K Nigam

    2002-05-01

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

  2. Neutron scattering from -Ce at epithermal neutron energies

    Indian Academy of Sciences (India)

    A P Murani

    2008-10-01

    Neutron scattering data, using neutrons of incident energies as high as 2 eV, on -Ce and -Ce-like systems such as CeRh2, CeNi2, CeFe24, CeRu2, and many others that point clearly to the substantially localized 4f electronic state in these systems are reviewed. The present interpretation is contrary to the widely held view that the 4f electrons in these systems form a narrow itinerant electron 4f band.

  3. CeO2-stabilized tetragonal ZrO2 polycrystals (Ce-TZP ceramics)

    International Nuclear Information System (INIS)

    This work presents the development and the characterization of CeO2-stabilized tetragonal ZrO2 polycrystals (Ce-TZP ceramics), since it is considered candidate material for applications as structural high performance ceramics. Sintered ceramics were fabricated from mixtures of powders containing different CeO2 content prepared by conventional and nonconventional techniques. These powders and their resultant sintered ceramics were specified by chemical and physical characterization, compactation state and mechanical properties. The chemical characteristics were determined by chemical analysis and the physical characteristics were evaluated by phase content, particle and agglomerate size and aspect, and powder porosity. (author)

  4. Resistividade do filme depositado via sol-gel e estado de oxidação do dopante Ce na matriz SnO2 Resistivity of the film deposited via sol-gel and oxidation state of Ce doping in SnO2 matrix

    Directory of Open Access Journals (Sweden)

    L. V. A. Scalvi

    2011-06-01

    Full Text Available Incorporação de Ce3+ ou Ce4+ em filmes finos de SnO2 depositados via sol-gel-dip-coating aumenta drasticamente a resistividade elétrica. No primeiro caso, temos comportamento aceitador do dopante, levando a matriz à alta compensação de carga. Por outro lado, para Ce4+, verifica-se aumento na largura da região de depleção do contorno de grão, resultando em maior espalhamento de elétrons. Medidas de caracterização elétrica sob pressão ambiente levam à barreiras de potencial mais altas do que as medidas sob vácuo, devido a adsorção de oxigênio na superfície das partículas. A presença de Ce3+ aumenta a transmitância no infravermelho, o que significa menor quantidade de elétrons livres. Dados de XANES confirmam que o tratamento térmico a 550 ºC dos filmes, ainda que promova oxidação parcial para Ce4+, preserva uma quantidade significativa (em torno de 60% no estado Ce3+. Espectroscopia Raman mostra a evolução dos modos de vibração intra-grãos de SnO2 com o aumento da temperatura de tratamento térmico.Incorporation of Ce3+ or Ce4+ in sol-gel dip-coating SnO2 thin films increases drastically its electrical resistivity. In the first case, it is due the acceptor-like nature of the doping ion, leading the matrix to high charge compensation. On the other hand, for Ce+4 doped samples, it is verified a broadening of the grain boundary depletion layer. Measurements under room pressure leads to higher intergrain potential barriers when compared to measurements carried out under vacuum conditions, due to oxygen adsorption at particles surface. The presence of Ce3+ increases the infrared transmittance, which means a lower free electron concentration. XANES data confirms that the thermal annealing at 550 ºC of thin films, although promotes oxidation to Ce4+, still keeps a significantly amount (about 60% of ions in the oxidation state Ce3+. Raman spectroscopy data show the evolution of the SnO2 bulk vibration modes with

  5. Seebeck coefficient of CePd3

    International Nuclear Information System (INIS)

    Rare earth compounds have potential applications in thermoelectric devices due to their large value conductivity and Seebeck coefficient. CePd3 has the highest reported Seebeck coefficient (S ∼ 125 μV/K), when doped appropriately, among all rare-earth compounds. This high value is explained as a result of the placement of the cerium f1 level. (author)

  6. Simplifying instrumentation for CE-MS analysis

    Czech Academy of Sciences Publication Activity Database

    Týčová, Anna; Foret, František

    Vienna, 2015. s. 37-37. [MassSpec-Forum-Vienna-2015. 17.02.2015-18.02.2015, Vienna] R&D Projects: GA ČR(CZ) GBP206/12/G014; GA ČR(CZ) GA15-15479S Institutional support: RVO:68081715 Keywords : interface * CE-MS * sheathless Subject RIV: CB - Analytical Chemistry, Separation

  7. The Doniach diagram and hydrogenation of the ternary compounds CePdIn and CePdSn

    OpenAIRE

    Chevalier, Bernard; Wattiaux, Alain; Bobet, Jean-Louis

    2006-01-01

    The process of hydrogenation of the antiferromagnetic compounds CePdIn and CePdSn has been studied. Investigation of the new hydrides CePdInH and CePdSnH by means of x-ray powder diffraction reveals that they adopt the same crystal symmetry as the original intermetallic but the unit cell volume increases during the hydrogenation. Magnetization, electrical resistivity, thermoelectric power and 119Sn Mössbauer spectroscopy measurements reveal that CePdInH and CePdSnH order antiferromagnetically...

  8. Some regularities of Ce(3) and Ce(4) stabilization in their compounds with β-diketones

    International Nuclear Information System (INIS)

    Adduct formation of cerium (3) and cerium (4) β-diketonates (acetylacetonate, benzoylacetonate, dibenzoylmethanate and thenoyltrifluoroacetonate) with oxygen- and nitrogen-donor ligands (Q-α, α'-dipyridyl, o-phenanthroline, trioctylphosphine oxide and triphenylphosphine oxide) is studied. The compounds obtained as a results of the reactions are studied by means of IR-spectroscopic, derivatographic and X-ray phase methods. It is concluded that composition and thermodynamic stability of adducts of Ce(3) tris-β-diketonates are determined by correlation of donor properties of the basis and additional ligand and stability of adducts to oxidation - as well as by their solubility. Introduction of the additional ligand to the system Ce(4)-β-diketones even in the presence of air oxygen stabilizes Ce(3) and destabilizes Ce(4)

  9. Proton induced activation of LaBr3:Ce and LaCl3:Ce

    International Nuclear Information System (INIS)

    In the framework of an assessment of lanthanum halide scintillators, such as LaBr3:Ce and LaCl3:Ce on their suitability for space based gamma-ray spectroscopy, proton induced activation of the materials has been studied. One inch scintillators were subjected to proton irradiations in the range of 60-184 MeV, where after the activation was measured. The activation was analyzed by identifying the decaying isotopes by means of gamma-ray spectroscopy and lifetime measurements using both a germanium detector and the activated scintillator itself. It was found that the dominant source of activation in the scintillators originates from the lighter elements in the materials: bromide and chloride, respectively. The activation of LaBr3:Ce manifest itself through gamma-decay, which partly leaves the volume. Activation of LaCl3:Ce originates mainly from beta decay, which is confined to the volume itself

  10. Reference Gene Selection in the Desert Plant <em>Eremosparton songoricuem>m>

    Directory of Open Access Journals (Sweden)

    Dao-Yuan Zhang

    2012-06-01

    Full Text Available <em>Eremosparton songoricum em>(Litv. Vass. (<em>E. songoricumem> is a rare and extremely drought-tolerant desert plant that holds promise as a model organism for the identification of genes associated with water deficit stress. Here, we cloned and evaluated the expression of eight candidate reference genes using quantitative real-time reverse transcriptase polymerase chain reactions. The expression of these candidate reference genes was analyzed in a diverse set of 20 samples including various <em>E. songoricumem> plant tissues exposed to multiple environmental stresses. GeNorm analysis indicated that expression stability varied between the reference genes in the different experimental conditions, but the two most stable reference genes were sufficient for normalization in most conditions.<em> EsEFem> and <em>Esα-TUB> were sufficient for various stress conditions, <em>EsEF> and <em>EsACT> were suitable for samples of differing germination stages, and <em>EsGAPDH>and <em>Es>UBQ em>were most stable across multiple adult tissue samples. The <em>Es18Sem> gene was unsuitable as a reference gene in our analysis. In addition, the expression level of the drought-stress related transcription factor <em>EsDREB2em>> em>verified the utility of<em> E. songoricumem> reference genes and indicated that no single gene was adequate for normalization on its own. This is the first systematic report on the selection of reference genes in <em>E. songoricumem>, and these data will facilitate future work on gene expression in this species.

  11. cDNA library Table: ce-- [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available ce-- NA ce-- C202 x J201 compound eyes mixture of fifth instar larval stage to pupa...l stage mixed pBluescript SK- EcoR1 for 5' Xho1for 3' sequenced from T3 primer (5' -> 3') BP117205-BP118782 ce--[number] ...

  12. INCA-CE project: status and results

    Science.gov (United States)

    Strauss, Franziska; Meirold-Mautner, Ingo; Bica, Benedikt; Kann, Alexander; Wang, Yong

    2013-04-01

    Every year, Central Europe (CE) is affected by weather extremes challenging civil protection authorities, hydrologists and road maintenance services to timely warnings. Within the INCA-CE project (Integrated Nowcasting through Comprehensive Analysis in Central Europe; http://www.inca-ce.eu) which is supported by the European Regional Development Fund a deepened transnational cooperation between meteorological/hydrological services and three application areas is established. This guarantees for both enhancements of meteorological products in the sense of end-user friendliness, and standardized information exchange across borders. At present, INCA-CE is the only project throughout the world which connects cooperation to such an extent with respect to its transnational and multidisciplinary framework (in the meanwhile it has been chosen as World Weather Research Programme/Forecast Demonstration Project by the World Meteorological Organization). Key partners from eight countries (from national meteorological/hydrological services and the three different application areas) accept the challenge to work on standardization and harmonization tools. Therefore, the INCA nowcasting system - developed at the Austrian weather service (ZAMG) in the 1990ies - has been implemented at all CE meteorological/hydrological services and is advanced and refined to the specific user needs to (i) provide high quality nowcasting products which are standardized and harmonized across borders, (ii) improve information chains from models to warnings and protection measures in case of disaster, and (iii) make the public and stakeholders more familiar with meteorological products. However, the potential to achieve these listed improvements is only possible through the intense transnational and multidisciplinary cooperation, because for one institution and one country alone it would be impossible to cope with all the necessary tasks. In this presentation the status and results of the INCA-CE

  13. Effect of La,Ce,Tb Concentration on Luminescence Properties of (La,Ce,Tb)BO3%La,Ce,Tb含量对(La,Ce,Tb)BO3发光性能的影响

    Institute of Scientific and Technical Information of China (English)

    王林生; 黄可龙; 周智; 文小强; 周健; 赖华生

    2012-01-01

    采用高温固相法合成(La,Ce,Tb)BO3荧光粉,并对该荧光粉进行XRD和SEM分析.结果表明:(La,Ce,Tb)BO3的晶体结构和LaBO3相同,Ce3+,Tb3+的掺入没有改变晶体的结构,发光粉颗粒大小均匀,形貌规则,粒度在5 μm左右.研究了(La,Ce,Tb)BO3的光谱性质,在(La,Ce,Tb)BO3的发射和激发光谱中除了有Tb3+的特征发射和激发峰外,还有Ce3+的特征发射和激发峰.%The phosphors of (La,Ce,Tb)BO3 were synthesized by high temperature solid state reaction. X-ray diffractometry (XRD) patterns indicate that the crystal structures of (La,Ce,Tb)BO3 and LaBO3 are the same. The crystal structure has not been changed by Ce3+ and Tb3+ doping. Emission scanning electron microscopy (SEM) images show that the particle sizes of phosphors are more uniform, the morphology is more regular, and the granularity is about 5 μm. The content of TbBO3 phase in (La,Ce,Tb)BO3 increases with increasing of Tb content in (La,Ce,Tb)BO3. When Tb concentration reaches 15% and above, the content of TbBO3 phase in (La,Ce,Tb)BO3 increases more rapidly. The luminescence properties of (La,Ce,Tb)BO3 and the sensitization of Ce to Tb were studied. In the excitation spectrum of Ce there are three peaks at 244, 268 and 330 nm, respectively. And in the emission spectrum of Ce , there are two peaks at 365 and 380 nm, respectively. All of them have the large overlap. The Maximum emission wavelength of Tb3+ is 541 nm, and its excitation peaks is 230 nm. Both the Tb characteristic emission and excitation peaks and the Ce characteristic emission and excitation peaks were observed in the emission and excitation spectrum of (La,Ce,Tb)BO3. Comparing the excitation spectrum of (La,Ce)BO3 with the emission spectrum of (La,Tb)BO3, it is found that they have the large overlap. It is indicated that there is a remarkable energy transfer from Ce to Tb in (La,Ce,Tb)BO3. When the concentration of Ce or Tb in (La,Ce,Tb)BO3 is fixed, because of concentration self

  14. Synthesis, Crystal Structure and Luminescent Property of Cd (II Complex with <em>N-Benzenesulphonyl-L>-leucine

    Directory of Open Access Journals (Sweden)

    Xishi Tai

    2012-09-01

    Full Text Available A new trinuclear Cd (II complex [Cd3(L6(2,2-bipyridine3] [L =<em> Nem>-phenylsulfonyl-L>-leucinato] has been synthesized and characterized by elemental analysis, IR and X-ray single crystal diffraction analysis. The results show that the complex belongs to the orthorhombic, space group<em> Pem>212121 with<em> aem> = 16.877(3 Å, <em>b> em>= 22.875(5 Å, <em>c em>= 29.495(6 Å, <em>α> em>= <emem>= <emem>= 90°, <em>V> em>= 11387(4 Å3, <em>Z> em>= 4, <em>Dc>= 1.416 μg·m−3, <emem>= 0.737 mm−1, <em>F> em>(000 = 4992, and final <em>R>1 = 0.0390, <em>ωR>2 = 0.0989. The complex comprises two seven-coordinated Cd (II atoms, with a N2O5 distorted pengonal bipyramidal coordination environment and a six-coordinated Cd (II atom, with a N2O4 distorted octahedral coordination environment. The molecules form one dimensional chain structure by the interaction of bridged carboxylato groups, hydrogen bonds and p-p interaction of 2,2-bipyridine. The luminescent properties of the Cd (II complex and <em>N-Benzenesulphonyl-L>-leucine in solid and in CH3OH solution also have been investigated.

  15. The cerium ground state in the intermetallic compounds Al2Ce, Al3Ce at very low temperature

    International Nuclear Information System (INIS)

    Nuclear orientation experiments show the different behaviour between the Al2Ce and Al3Ce compounds. Despite the occurrence of a Kondo coupling, the first compound is well ordered down to 5 mK. No long range ordering seems to exist in Al3Ce but crystal field effects can partly mask the ordering. (author)

  16. Cerium intermetallics CeTX. Review III

    International Nuclear Information System (INIS)

    The structure-property relationships of CeTX intermetallics with structures other than the ZrNiAl and TiNiSi type are systematically reviewed. These CeTX phases form with electron-poor and electron-rich transition metals (T) and X = Mg, Zn, Cd, Hg, Al, Ga, In, Tl, Si, Ge, Sn, Pb, P, As, Sb, and Bi. The review focusses on the crystal chemistry, the chemical bonding peculiarities, and the magnetic and transport properties. Furthermore 119Sn Moessbauer spectroscopic data, high-pressure studies, hydrogenation reactions and the formation of solid solutions are reviewed. This paper is the third of a series of four reviews on equiatomic intermetallic cerium compound [Part I: R. Poettgen, B. Chevalier, Z. Naturforsch. 2015, 70b, 289; Part II: R. Poettgen, B. Chevalier, Z. Naturforsch. 2015, 70b, 695].

  17. Maanhonka hirsitalot CE-merkintä

    OpenAIRE

    Nieminen, Ville

    2012-01-01

    Tämän insinöörityön tarkoitus oli saada päivitettyä Maanhonka hirsitalojen ETA, joka oli mennyt vanhaksi marraskuussa 2010. ETA-hyväksynnän ja vaatimuksen-mukaisuustodistuksen myötä on tarkoitus hakea yritykselle CE-merkintäoikeus. CE-merkintä tulee pakolliseksi talotehtaille ja kaikille rakennustuotteille 1.7.2013 alkaen. Prosessi kestää yrityksestä riippuen vähintään puolesta vuodesta vuoteen. Riippuen siitä, mitä ETAan sisällytetään ja mitä testejä yrityksellä on jo ennestään tehtynä. VTT:...

  18. Cerium intermetallics CeTX. Review III

    Energy Technology Data Exchange (ETDEWEB)

    Poettgen, Rainer; Janka, Oliver [Muenster Univ. (Germany). Inst. fuer Anorganische und Analytische Chemie; Chevalier, Bernard [Bordeaux Univ., Pessac (France). Inst. de Chimie de la Matiere Condensee de Bordeaux

    2016-05-01

    The structure-property relationships of CeTX intermetallics with structures other than the ZrNiAl and TiNiSi type are systematically reviewed. These CeTX phases form with electron-poor and electron-rich transition metals (T) and X = Mg, Zn, Cd, Hg, Al, Ga, In, Tl, Si, Ge, Sn, Pb, P, As, Sb, and Bi. The review focusses on the crystal chemistry, the chemical bonding peculiarities, and the magnetic and transport properties. Furthermore {sup 119}Sn Moessbauer spectroscopic data, high-pressure studies, hydrogenation reactions and the formation of solid solutions are reviewed. This paper is the third of a series of four reviews on equiatomic intermetallic cerium compound [Part I: R. Poettgen, B. Chevalier, Z. Naturforsch. 2015, 70b, 289; Part II: R. Poettgen, B. Chevalier, Z. Naturforsch. 2015, 70b, 695].

  19. Low flow electrospray interfacing CE/MS

    Czech Academy of Sciences Publication Activity Database

    Foret, František; Týčová, Anna; Křenková, Jana; Klepárník, Karel

    2015. L-10. ISBN N. [International Symposium on Electro- and Liquid Phase-Separation Techniques (ITP2015) /22./ and the Nordic Separation Science (NoSSS) symposium /8./. 30.08.2015-03.09.2015, Helsinki] R&D Projects: GA ČR(CZ) GBP206/12/G014 Institutional support: RVO:68081715 Keywords : electrospray * CE/MS * GAP20612G014 Subject RIV: CB - Analytical Chemistry, Separation

  20. Thermoemission of Ce+ ions and its fluctuations

    Science.gov (United States)

    Gladyszewski, Longin

    1994-12-01

    The surface ionization of cerium on tungsten and its fluctuatins (noises) have been studied using a single filament ion source in a 90° magnetic mass spectrometer. The statistical behaviour of the spectral density and autocorrelation functions for Ce+ ion thermoemission noise were investigated by means of a special stochastic analyser. These noises are generated as a result of adsorbate density fluctuations. The method used made it possible to determine the atom desorption and migration energy for cerium from tungsten.

  1. The CeDRES data portal

    Science.gov (United States)

    Albert-Aguilar, Alexandre; Delmotte, Pauline; André, François; Brissebrat, Guillaume; Canonici, Jean-Christophe; Piguet, Bruno

    2016-04-01

    SAFIRE is the French facility dedicated to airborne measurement for environmental research. The SAFIRE steering committee decided that access to its archives should be improved. If certain data, including recent campaigns, are available online, access to them is difficult for users because these data are dispersed in as many data portals as campaigns. Most of projects are not able to keep medium to long term online access to their database. Therefore, many airborne data, particularly the oldest, are not available online, stored on media whose sustainability is not guaranteed. SAFIRE also decided to identify old data stored in Meudon (France) on paper and hard media and to rescue with the help of an archivist. At the same time, the development of a centralized digital archive - containing data collected with the Fokker - 27 " ARAT " and Merlin IV aircraft - associated to a web portal was given to SEDOO. The first part of the project consisted in modelling the database. The second part, still in progess, was the development of the CeDRES (Centre de Données aéRoportées & SAFIRE) portal (http://cedres.sedoo.fr) which is responsive and bilingual (French and English) ; and metadata standardization (iso 19115). The main objectives of this project are data preservation and open data access. A first test version of CeDRES portal will be release in mid-February 2016. And operational version is planned for summer 2016. In the future, CeDRES portal will be able to receive and to distribute metadata and data of aircraft currently in service (FALCON-20, ATR-42 and PiperAztec-23). The interoperability implementation and data homogenization are planned in the medium term. The CeDRES portal is part of the French atmospheric chemistry data center AERIS (http://www.aeris-data.fr). Every scientist is invited to browse the catalog and use CEDRES data. Feel free to contact cedres-contact@sedoo.fr for any question.

  2. Convenient synthesis of CeO2 nanotubes

    International Nuclear Information System (INIS)

    A simple and facile route was used in the fabrication of CeO2 nanotubes within anodic alumina membrane. A piece of membrane was first immersed into Ce(NO3)3 aqueous solution under ambient conditions. After dried at 50 deg. C and thermally calcined at 150 deg. C and 550 deg. C, CeO2 nanotubes can be easily synthesized. The characterization with electron microscopy and X-ray diffraction indicated that CeO2 nanotubes were composed of tiny well-crystalline CeO2 nanoparticles

  3. YAP (Ce) as focal plane detectors

    International Nuclear Information System (INIS)

    YAP (Ce) has been known to be one of the commercially available new scintillators that can be used for several applications. It has a good timing response and a very high value for the radiation hardness, compared to other known inorganic scintillators. Several studies have been reported on the properties of the scintillator, viz., light yield, decay time constant, gamma and charged particle response, pulse shape discrimination and timing characteristics. The YAP(Ce) crystals has a very good response to the energetic heavy ions and attempts have been made to employ it as a viable alternative to the Si detectors for the detection of heavy ions. As a part of the experimental facilities, being developed for the upcoming Superconducting cyclotron at VECC, the possibility is being explored for using the YAP(Ce) as an E detector, preceded by a position sensitive MWPCs as αE counterpart, at the focal plane of the proposed superconducting solenoid spectrometer. The selection of Photo Multiplier Tubes (PMT) has been very crucial in such cases in order to have good timing response and energy resolution for energetic heavy ions. The responses have been tested for different bias voltages of the tube and the best values have been reported here

  4. Constituição de sujeitos na gestão em saúde: avanços e desafios da experiência de Fortaleza (CE) The strengthening of subjects in health management: advances and challenges in the experience of Fortaleza, state of Ceará

    OpenAIRE

    Carmem Emmanuely Leitão Araújo; Ricardo José Soares Pontes

    2012-01-01

    Trata-se de uma pesquisa sobre possibilidades e limites da constituição de sujeitos na gestão em saúde, a partir da experiência de Fortaleza no período de 2005 a 2008. Aborda-se o sujeito a partir de um referencial histórico-cultural, o qual considera a interação dialética entre o individual e o coletivo no aprofundamento da consciência humana sobre si e o mundo. Foram realizados grupos focais com gestores vinculados à Atenção Primária à Saúde e utilizados dados secundários. Por meio de uma a...

  5. Ce(III)/Ce(IV) in methanesulfonic acid as the positive half cell of a redox flow battery

    International Nuclear Information System (INIS)

    The characteristics of the Ce(III)/Ce(IV) redox couple in methanesulfonic acid were studied at a platinum disk electrode (0.125 cm2) over a wide range of electrolyte compositions and temperatures: cerium (III) methanesulfonate (0.1-1.2 mol dm-3), methanesulfonic acid (0.1-5.0 mol dm-3) and electrolyte temperatures (295-333 K). The cyclic voltammetry experiments indicated that the diffusion coefficient of Ce(III) ions was 0.5 x 10-6 cm2 s-1 and that the electrochemical kinetics for the oxidation of Ce(III) and the reduction of Ce(IV) was slow. The reversibility of the redox reaction depended on the electrolyte composition and improved at higher electrolyte temperatures. At higher methanesulfonic acid concentrations, the degree of oxygen evolution decreased by up to 50% when the acid concentration increased from 2 to 5 mol dm-3. The oxidation of Ce(III) and reduction of Ce(IV) were also investigated during a constant current batch electrolysis in a parallel plate zinc-cerium flow cell with a 3-dimensional platinised titanium mesh electrode. The current efficiencies over 4.5 h of the process Ce(III) to Ce(IV) and 3.3 h electrolysis of the reverse reaction Ce(IV) to Ce(III) were 94.0 and 97.6%, respectively. With a 2-dimensional, planar platinised titanium electrode (9 cm2 area), the redox reaction of the Ce(III)/Ce(IV) system was under mass-transport control, while the reaction on the 3-dimensional mesh electrode was initially under charge-transfer control but became mass-transport controlled after 2.5-3 h of electrolysis. The effect of the side reactions (hydrogen and oxygen evolution) on the current efficiencies and the conversion of Ce(III) and Ce(IV) are discussed.

  6. Moessbauer studies of nano phase Ce-Fe oxide composites

    International Nuclear Information System (INIS)

    Chemical co-precipitation method was used to synthesize nano-structured α-Fe2O3-CeO2 composite by calcination of the goethite-cerium hydroxide precursor. It was observed that the precursor contained goethite matrix doped with cerium. Calcination of the precursor at 400oC showed the formation of nanosize hematite. Moessbauer spectra show the presence of a paramagnetic component in the precursor but not in the samples calcined at 400oC to 800oC temperatures. Our study shows that Ce precipitated as CeO2 and stuck on the surface of hematite particles. The precipitation of Ce as CeO2 is independent of the concentration of Ce in the Ce-Fe-O composite.

  7. Evaluation of Antioxidant and Antiproliferative Properties of Three <em>Actinidia> (<em>Actinidia> <em>kolomikta>, <em>Actinidia argutaem>, <em>Actinidia> <em>chinensis> Extracts <em>in Vitroem>

    Directory of Open Access Journals (Sweden)

    Jia-Ren Liu

    2012-05-01

    Full Text Available The total phenolic content, total flavonoid content, vitamin C content, and antioxidant activities of ethanol extracts from different kiwifruit varieties (<em>Actinidia> <em>kolomikta>, <em>Actinidia argutaem>, <em>Actinidia> <em>chinensis> were determined in this study. Multiple scavenging activity assays including the hydroxyl radical, O2·radical, DPPH, and the ABTS+ radical scavenging activity assays were used to identify the antioxidant activities of <em>Actinidia> extracts. The cell viability of HepG2 and HT-29 cells was also examined in this study. The results demonstrated that the <em>Actinidia kolomiktaem> extract had a higher antioxidant activity than the other two <em>Actinidia> extracts. There is a positive correlation between antioxidant activity and the polyphenols and vitamin C content in all three extracts (<em>R>2 ≥ 0.712, <em>p> em>< 0.05. The <em>Actinidia argutaem> extract had the highest inhibitory effect on HepG2 and HT-29 cell growth. These results provide new insight into the health functions of fruit and demonstrate that <em>Actinidia> extracts can potentially have health benefits.

  8. A comparison between Ce(III) and Ce(IV) ions in photocatalytic degradation of organic pollutants

    Institute of Scientific and Technical Information of China (English)

    程强; 施薇; 段炼; 孙彬哲; 李晓霞; 徐爱华

    2015-01-01

    Nano cerium oxides are efficient photocatalysts for pollutants degradation with highly dispersed Ce(III) ions as the sug-gested active species to promote the reaction, while Ce(IV) species do not behave as a catalyst. In this paper, to understand the mechanism of Ce-based photocatalysts, we studied the comparison of simple cerium ions, Ce(III) and Ce(IV) in aqueous solution for organic pollutants degradation under UV irradiation. Orange II (AOII), methyl orange, andp-nitrophenol were selected as the target pollutants. The formation and contribution of reactive oxygen species, the kinetics of Ce(IV) photoreduction and Ce(III) photooxida-tion, and the influence of solution pH were investigated in detail. It was found that at low pH Ce(IV) ions showed a higher activity for hydroxyl radicals production and AOII degradation than Ce(III) ions, which could be attributed to its fast reduction rate to Ce(III). However, its activity dramatically decreased when solution pH increased, and was also strongly influenced by the type of pollutants; while Ce(III) exhibited high degradation efficiency of all the tested pollutants over a wide pH range.

  9. Grèce antique et Grèce moderne

    OpenAIRE

    Baud-Bovy, Samuel

    2015-01-01

    Alors que les savants grecs du siècle dernier, que ce soit pour faire plaisir aux philhellènes ou pour combattre la théorie de Fallermayer sur la slavisation de la Grèce au Moyen Age, mettaient tout en œuvre pour prouver que les Grecs modernes étaient les descendants directs des Grecs anciens, les générations suivantes se lassèrent de ce culte exclusif voué aux ancêtres. Il arrivait même à Palamas, le poète national du XXe siècle naissant, de s’insurger contre cette mentalité : Les tombes, mê...

  10. ÍNDÍCE DE RECUPERAÇÃO DE OÓCITOS BOVINOS OBTIDOS DE OVÁRIOS ADQUIRIDOS EM ABATEDOURO COMO CONTRIBUIÇÃO PARA OS ESTUDOS DE FECUNDAÇÃO E PRODUÇÃO DE EMBRIÕES IN VITRO

    Directory of Open Access Journals (Sweden)

    AGOSTINHO. Maria Avanci

    2009-05-01

    Full Text Available The production of embryos in vitro is a biotechnology used, alternatively, to accelerate theproduction of genetically superior animals in addition to the deepening of knowledge concerning physiologicalprocesses, biochemical and biotechnological interest of the animal. The development of techniques in vitro toproduce embryos of domestic animals has great potential both for basic research and for applications in the fieldand has been widely used and distributed in Brazil and abroad. This study aimed to classify bovine oocytes obtainedfrom ovaries acquired in a slaughterhouse, determining the rate of recovery of these structures and identifying themost viable for the procedure for in vitro fertilization. Through follicular aspiration, oocytes were ranked in scalefrom 1 to 4, according to the amount of layers of cells in the complex cumulus oophorus involving the oocyte.There was 15.22% of high-quality oocytes 1; 25.88% of quality 2; 35.53% from 23.35% quality 3 and quality 4,setting higher rates of oocytes recovered classified as 2 and 3, which are physiologically viable and able to enterinto a program of in vitro fertilization.A produção in vitro de embriões é uma biotécnica utilizada, alternativamente, para acelerar aprodução de animais geneticamente superiores além de permitir o aprofundamento dos conhecimentos relativosaos processos fisiológicos, bioquímicos e biotecnológicos da espécie animal de interesse. O desenvolvimento detécnicas in vitro para a produção de embriões de animais domésticos tem grande potencial tanto para pesquisabásica quanto para aplicações a campo e tem sido muito utilizadas e difundidas no Brasil e no mundo. O presentetrabalho objetivou classificar oócitos bovinos obtidos de ovários adquiridos em abatedouro, determinando o índicede recuperação dessas estruturas e identificando os de maior viabilidade para o procedimento de fertilização invitro. Através da aspiração folicular, foram obtidos o

  11. Preparation and electrical characterization of electrolytes obtained from solid solution (Zr{sub 0.84}Y{sub 0.16O1.90}) x (Ce{sub 0.80}Gd{sub 0.20}O{sub 1.90}){sub 1-x} for fuel cells application; Preparacao e caracterizacao eletrica de eletrolitos obtidos a partir da solucao solida (Zr{sub 0.84}Y{sub 0.16O1.90}) x (Ce{sub 0.80}Gd{sub 0.20}O{sub 1.90}){sub 1-x} para aplicacao em pilhas de combustivel

    Energy Technology Data Exchange (ETDEWEB)

    Tonelli, Bruno C.; Antunes, Fabio C.; Souza, Dulcina P.F. de, E-mail: fcaufscar@yahoo.com.b [Universidade Federal de Sao Carlos (LAPCEC/UFSCar), SP (Brazil). Programa de Pos-Graduacao em Ciencia e Engenharia de Materiais. Lab. de Preparacao e Caracterizacao Eletrica em Ceramicas

    2010-07-01

    Oxide fuel cells based on yttria stabilized zirconia (YSZ) operates near 1000 deg C. This high temperature results in physical and chemical degradation of the device. Rare earths doped ceria (REC) based systems can operate at low temperatures due to higher ionic conductivity. However, at low oxygen partial pressure, doped ceria shows n-type electronic conductivity due to reduction of Ce{sup +4} to Ce{sup +3}. Trying to put together the zirconia and ceria advantage, YSZ-REC composites have been investigated. In this work, YSZ-GdDC powders mixtures were prepared and pellets were isostatically pressed. Pellets were sintered 1100-1500 deg C temperature range. Sintered pellets were characterized by density measurements, X-ray diffraction, impedance spectroscopy and scanning electron microscopy. The experimental procedure adopted in this work generated solid solutions instead of composite samples. Nevertheless, the composition containing {approx}76 vol.% of YSZ, in spite of the high porosity, showed electrical conductivity similar to pure YSZ. (author)

  12. <em>α>-Glucosidase Inhibitory Constituents from <em>Acanthopanax senticosusem> Harm Leaves

    Directory of Open Access Journals (Sweden)

    Hai-Xue Kuang

    2012-05-01

    Full Text Available A new triterpene glycoside, 3-<em>O-[(α>-L-rhamnopyranosyl(1→2]-[<em>β>-D-glucuronopyranosyl-6-<em>O>-methyl ester]-olean-12-ene-28-olic acid (1 and a new indole alkaloid, 5-methoxy-2-oxoindolin-3-acetic acid methyl ester (5 were isolated from the leaves of <em>Acanthopanax senticosusem> Harms along with six known compounds. The structures of the new compounds were determined by means of 2D-NMR experiments and chemical methods. All the isolated compounds were evaluated for their glycosidase inhibition activities and compound 6 showed significant <em>α>-glucosidase inhibition activity.

  13. A study of the Ce3+/Ce4+ redox couple in sulfamic acid for redox battery application

    International Nuclear Information System (INIS)

    Highlights: ► SA served as media electrolyte for Ce3+/Ce4+ was reported. ► A Zn–Ce redox battery was assembled and it showed impressive charge–discharge performance. ► The performance of Zn–Ce battery was improved by adding carbonate such as NH4HCO3. Its energy efficiency reached up to 53%. -- Abstract: The present paper reports a cerium sulfamate electrolyte for use in redox battery. The electrochemical behavior of Ce3+/Ce4+ in sulfamic acid (SA) media has been investigated using linear-sweep voltammetry and cyclic voltammetry. The formal potential of the Ce3+/Ce4+ redox couple in SA is approximately 1.52 V vs. NHE. The exchange current density and standard rate constant of the Ce3+/Ce4+ redox reaction on platinum electrode in SA are determined as 5.95 × 10−4 A cm−2 and 4.95 × 10−5 cm s−1 respectively. The diffusion coefficient of Ce3+ in SA is 5.93 × 10−6 cm2 s−1. The conductivity of cerium(III) sulfamate solution is improved significantly by adding NH4+. A zinc–cerium test cell with Ce3+/Ce4+ sulfamate solution as the positive electrolyte is constructed and the charge-discharge performance is evaluated. The coulombic efficiency of the Zn–Ce cell is calculated to be 90%. The preliminary exploration shows that the cerium sulfamate electrolyte is promising for redox battery application and is worthy of further study.

  14. Role of the Ce valence in the coexistence of superconductivity and ferromagnetism of CeO$_{1-x}$F$_{x}$BiS$_{2}$ revealed by Ce $L_3$-edge x-ray absorption spectroscopy

    OpenAIRE

    Sugimoto, Takuya; Joseph, Boby; Paris, Eugenio; Iadecola, Antenolla; Mizokawa, Takashi; Demura, Satoshi; Mizuguchi, Yoshikazu; Takano, Yoshihiko; Saini, Naurang L.

    2014-01-01

    We have performed Ce $L_3$-edge x-ray absorption spectroscopy (XAS) measurements on CeO$_{1-x}$F$_x$BiS$_2$, in which the superconductivity of the BiS$_2$ layer and the ferromagnetism of the CeO$_{1-x}$F$_x$ layer are induced by the F-doping, in order to investigate the impact of the F-doping on the local electronic and lattice structures. The Ce $L_3$-edge XAS spectrum of CeOBiS$_2$ exhibits coexistence of $4f^1$ (Ce$^{3+}$) and $4f^0$ (Ce$^{4+}$) state transitions revealing Ce mixed valency...

  15. Study of Ce-modified antibacterial 316L stainless steel

    Directory of Open Access Journals (Sweden)

    Yuan Junping

    2012-11-01

    Full Text Available 316L stainless steel is widely used for fashion jewelry, but it can carry a large number of bacteria and bring the risk of infection since the steel has no antimicrobial performance. In this paper, the effects of Ce on the antibacterial property, corrosion resistance and processability of 316L were studied by microscopic observation, thin-film adhering quantitative bacteriostasis, and electrochemical and mechanical tests. The results show that a trace of Ce can distribute uniformly in the matrix of 316L and slightly improve its corrosion resistance in artificial sweat. With an increase in Ce content, the Ce is prone to form clustering, which degrades the corrosion resistance and the processability. The Ce-containing 316L exhibits Hormesis effect against S. aureus. A small Ce addition stimulates the growth of S. aureus. As the Ce content increases, the modified 316L exhibits an improved antibacterial efficacy. The more Ce is added, the better antibacterial capability is achieved. Overall, if the 316L is modified with Ce alone, it is difficult to obtain the optimal combination of corrosion resistance, antibacterial performance and processability. In spite of that, 0.15 wt.%-0.20 wt.% Ce around is inferred to be the best trade-off.

  16. Low temperature magnetic behavior of Ce7Ni3

    International Nuclear Information System (INIS)

    Low-temperature specific heat (CP) (70 mK7Ni3 (under applied magnetic fields up to B=6 T) are presented. The maxima in CP (at 1.55 K) and in χ (at 1.85 K) are related to an antiferromagnetic (AF) type transition. The experimental results are interpreted in terms of three Ce sublattices (1CeI, 3CeII and 3CeIII atoms per formula unit) of the Th7Ni3-type structure. These sublattices correspond to the three different Ce local environments. According to the entropy gain the AF order is related to the CeI sublattice and the CeII atoms behave as heavy fermions, with γLT∼2.7 J/CeII-at.K2 and a characteristic temperature of TK∼4 K. The CeIII atoms are responsible for an intermediate valence behavior with γHT∼0.3 J/CeIII-at.K2 and a characteristic temperature of T0∼70 K, which is confirmed by the ln T dependence of the electrical resistivity. ((orig.))

  17. Electrical resistivity of CeFe2

    International Nuclear Information System (INIS)

    Electrical and magneitc properties of CeFe2 were investigated from the temperature dependence of electrical resistivity in the range of 1,5 to 3000K. The critical temperature, determined from the maximum of dp/dT, gives T sub(c) = 2200K and the temperature independent magnetic resistivity is 87μωcm. This value is compared with the corresponding in YFe2. At low temperature the resistivity shows a fairly large variation proportional to AT2 up to about 320K with A = 1,2x10-2 μωcm/0K2. (Author)

  18. Internal bremsstrahlung spectrum of 139Ce

    International Nuclear Information System (INIS)

    The internal bremsstrahlung spectrum which accompanies the electron capture decay of 139Ce to the first excited state of 139La has been measured in coincidence with the nuclear gamma ray which deexcites that state. The measured intensity above 42 keV is found to be (1.070±0.024) times that predicted by the recent calculations of Suriacute c et al. The QEC value is found to be 264.6±2.0 keV. copyright 1996 The American Physical Society

  19. Crystal structure and solution species of Ce(III) and Ce(IV) formates: from mononuclear to hexanuclear complexes.

    Science.gov (United States)

    Hennig, Christoph; Ikeda-Ohno, Atsushi; Kraus, Werner; Weiss, Stephan; Pattison, Philip; Emerich, Hermann; Abdala, Paula M; Scheinost, Andreas C

    2013-10-21

    Cerium(III) and cerium(IV) both form formate complexes. However, their species in aqueous solution and the solid-state structures are surprisingly different. The species in aqueous solutions were investigated with Ce K-edge EXAFS spectroscopy. Ce(III) formate shows only mononuclear complexes, which is in agreement with the predicted mononuclear species of Ce(HCOO)(2+) and Ce(HCOO)2(+). In contrast, Ce(IV) formate forms in aqueous solution a stable hexanuclear complex of [Ce6(μ3-O)4(μ3-OH)4(HCOO)x(NO3)y](12-x-y). The structural differences reflect the different influence of hydrolysis, which is weak for Ce(III) and strong for Ce(IV). Hydrolysis of Ce(IV) ions causes initial polymerization while complexation through HCOO(-) results in 12 chelate rings stabilizing the hexanuclear Ce(IV) complex. Crystals were grown from the above-mentioned solutions. Two crystal structures of Ce(IV) formate were determined. Both form a hexanuclear complex with a [Ce6(μ3-O)4(μ3-OH)4](12+) core in aqueous HNO3/HCOOH solution. The pH titration with NaOH resulted in a structure with the composition [Ce6(μ3-O)4(μ3-OH)4(HCOO)10(NO3)2(H2O)3]·(H2O)9.5, while the pH adjustment with NH3 resulted in [Ce6(μ3-O)4(μ3-OH)4(HCOO)10(NO3)4]·(NO3)3(NH4)5(H2O)5. Furthermore, the crystal structure of Ce(III) formate, Ce(HCOO)3, was determined. The coordination polyhedron is a tricapped trigonal prism which is formed exclusively by nine HCOO(-) ligands. The hexanuclear Ce(IV) formate species from aqueous solution is widely preserved in the crystal structure, whereas the mononuclear solution species of Ce(III) formate undergoes a polymerization during the crystallization process. PMID:24090406

  20. Three New Myrsinol Diterpenes from <em>Euphorbia proliferaem> and Their Neuroprotective Activities

    Directory of Open Access Journals (Sweden)

    Yuanqiang Guo

    2012-08-01

    Full Text Available Three new myrsinol diterpenes were isolated from the roots of<em> em>>Euphorbia proliferaem>. Their structures were elucidated as 2<em>α-O>-isobutyryl-3<em>β>,5<em>α>,7<em>β>,10,15<em>β-penta-O>-acetyl-14<em>α-O>-benzoyl-10,18-dihydromyrsinol (1, 2<em>α-O>-isobutyryl-3<em>β-O>-propion-yl-5<em>α>,7<em>β>,10,15<em>β-tetra-O>-acetyl-10,18-dihydromyrsinol (2, and 2<em>α>,14<em>α-di-O>-benzoyl-3<em>β>,5<em>α>,7<em>β>,10,15<em>β-penta-O>-acetyl-10,18-dihydromyrsinol (3 on the basis of spectroscopic data analyses (IR, ESI-MS, HR-ESI-MS, and 1D and 2D NMR. Their neuroprotective activities were evaluated and compounds 1 and 2 showed neuroprotective effects against MPP+-induced neuronal cell death in SH-SY5Y cells.

  1. Bismuth flux growth of CeRh6Ge4 and CeRh2Ge2 single crystals

    International Nuclear Information System (INIS)

    Single crystals of the germanides CeRh6Ge4 and CeRh2Ge2 were synthesized from the elements in bismuth fluxes. Polycrystalline samples are available by arc-melting. The structures were refined on the basis of single-crystal X-ray diffractometer data. CeRh6Ge4: LiCo6P4 type, P anti 6m2, a = 715.4(2), c = 385.5(1) pm, wR2 = 0.0554, 273 F2 values, 19 variables; CeRh2Ge2: ThCr2Si2 type, I4/mmm, a = 415.69(6), c = 1048.5(2) pm, wR2 = 0.0391, 131 F2 values, 9 variables. The rhodium and germanium atoms build three-dimensional, covalently bonded [Rh6Ge4] and [Rh2Ge2] networks with Rh-Ge distances ranging from 246 to 255 pm. The cerium atoms are located in larger cavities within these networks: Ce rate at Ge6Rh12 in CeRh6Ge4 and Ce rate at Ge8Rh8 in CeRh2Ge2. Temperature-dependent magnetic susceptibility data of CeRh6Ge4 show Curie-Weiss behavior above 70 K with an experimental magnetic moment of 2.35(1) μB per Ce atom. Low-field measurements are indicative of magnetic ordering below 2.5 K. (orig.)

  2. Radiation resistant multicomponent inorganic materials for homogeneous EM-calorimeters

    International Nuclear Information System (INIS)

    With the development of a new generation of particle accelerators the interest for radiation resistant materials using for EM-calorimeters capable of withstanding a high radiation environment (107 rad/yr) has been increasing. The radiation resistance of fluoride solid solutions and heavy crystal oxides is investigated. A series of multicomponent crystals, solid solutions on the base of CeF2 and CdF2 with the radiation resistance above 109 rad is presented. 24 refs.; 4 figs

  3. A pressure study of CePt{sub 3}B

    Energy Technology Data Exchange (ETDEWEB)

    Rauch, Daniela; Suellow, Stefan [Institute of Condensed Matter Physics, University of Technology Braunschweig, Braunschweig (Germany); Hartwig, Steffen [Institute of Condensed Matter Physics, University of Technology Braunschweig, Braunschweig (Germany); BENSC, Helmholtz Zentrum Berlin, Berlin (Germany); Hidaka, Hiroyuki; Yamazaki, Seigo; Amitsuka, Hiroshi [Department of Physics, Hokkaido University, Sapporo (Japan); Bauer, Ernst [Institute of Solid State Physics, Vienna University of Technology, Vienna (Austria)

    2013-07-01

    CePt{sub 3}B is isostructural to the non-centro symmetric heavy-fermion superconductor CePt{sub 3}Si. In contrast to the latter system, CePt{sub 3}B exhibits a complex magnetically ordered state at low temperatures, with an antiferromagnetic phase below T{sub N}=7.8 K and a weakly ferromagnetic transition below T{sub C}∼5 K. CePt{sub 3}B can be understand as a low pressure variant of CePt{sub 3}Si. Here we report a study of CePt{sub 3}B by means of high pressure magnetization measurements, this way in particular accessing the pressure evolution of the ferromagnetic transition temperature T{sub C}. From our investigation up to about 40 kbar we observe an almost constant transition temperature T{sub C} with pressure. This behavior we discuss in the context of alloying studies on this material.

  4. Facile hydrothermal synthesis of CeO2 nanopebbles

    Indian Academy of Sciences (India)

    N Sabari Arul; D Mangalaraj; Jeong In Han

    2015-09-01

    Cerium oxide (CeO2) nanopebbles have been synthesized using a facile hydrothermal method. X-ray diffraction pattern (XRD) and transmission electron microscopy analyses confirm the presence of CeO2 nanopebbles. XRD shows the formation of cubic fluorite CeO2 and the average particle size estimated from the Scherrer formula was found to be 6.69 nm. X-ray absorption spectrum of CeO2 nanopebbles exhibits two main sharp white lines at 880 and 898 eV due to the spin orbital splitting of 4 and 5. Optical absorption for the synthesized CeO2 nanopebbles exhibited a blue shift (g = 3.35 eV) with respect to the bulk CeO2 (g = 3.19 eV), indicating the existence of quantum confinement effects.

  5. Constituição de sujeitos na gestão em saúde: avanços e desafios da experiência de Fortaleza (CE The strengthening of subjects in health management: advances and challenges in the experience of Fortaleza, state of Ceará

    Directory of Open Access Journals (Sweden)

    Carmem Emmanuely Leitão Araújo

    2012-09-01

    Full Text Available Trata-se de uma pesquisa sobre possibilidades e limites da constituição de sujeitos na gestão em saúde, a partir da experiência de Fortaleza no período de 2005 a 2008. Aborda-se o sujeito a partir de um referencial histórico-cultural, o qual considera a interação dialética entre o individual e o coletivo no aprofundamento da consciência humana sobre si e o mundo. Foram realizados grupos focais com gestores vinculados à Atenção Primária à Saúde e utilizados dados secundários. Por meio de uma abordagem hermenêutica dialética procurou-se compreender o sentido das narrativas construídas. Identificaram-se categorias empíricas que foram analisadas: cointencionalidade de mudança, direcionalidade política e conceitual, gestão humana, diminuição da hierarquia, fragmentação do processo de trabalho, concentração do poder de decisão. Sobressaíram-se reflexões sobre três políticas estratégicas: cogestão, humanização e educação permanente em saúde. Concluiu-se que, apesar da persistência de obstáculos, para a melhoria da qualidade dos sistemas e serviços de saúde é imprescindível instituir uma gestão democrática por meio de arranjos organizacionais e métodos participativos que potencializem a inserção e o comprometimento dos atores do Sistema Único de Saúde (SUS.This research deals with the potential and limitations of the strengthening of subjects in health management, based on the experience in Fortaleza in the period from 2005 to 2008. The subject is approached from a historical-cultural standpoint, which considers the dialectical interaction between the individual and the collective in deepening human consciousness on the self and the world. Focus groups were conducted with managers linked to Primary Healthcare and secondary data were utilized. An attempt was made to understand the meaning of the narratives constructed using a hermeneutic dialectic approach. Empirical categories were identified and

  6. Valence state of Ce and the magnetism in CeRh3B2

    International Nuclear Information System (INIS)

    The compound CeRh3B2 orders magnetically with a high Curie temperature (T/sub C/) of 115 K but with a low moment of only 0.4 μ/sub B/. L/sub III/ absorption-edge measurements show a dominant absorption peak at the energy corresponding to trivalent cerium. Magnetic studies on the compounds Ce(Rh/sub 1-x/T/sub x/)3B2 with T = Ru and Os reveal that the magnetic state is very rapidly broken up with the replacement of Rh by Ru and Os. These results, along with the observation of a high T/sub C/ in CeRh3B2, suggest that magnetism in this compound arises from a strong hybridization of nearly localized or slightly delocalized Ce 4f electrons with conduction electrons. The small moment may be due to a Kondo-type interaction coupled with crystal-field effects. 14 references, 4 figures

  7. Thermodynamic assessment of Al-Ce-Cu system

    International Nuclear Information System (INIS)

    The Ce-Cu binary system has been thermodynamically reassessed by CALPHAD approach based on experimental data and thermodynamic properties of phase diagram. Incorporating the thermodynamic evaluations of Al-Ce and Al-Cu systems from literature, the Al-Ce-Cu ternary system has been assessed using CALPHAD approach. The solution phases including liquid, Fcc and Bcc were treated as substitutional solution phases and the Redlich-Kister polynomial was used to describe their excess Gibbs energies. All binary and ternary intermetallic compounds were treated as stoichiometric phases and their Gibbs energies of formation were optimized. The calculated Al-Ce-Cu phase diagram agreed well with available experimental data.

  8. Complex charge ordering in CeRuSn

    Energy Technology Data Exchange (ETDEWEB)

    Feyerherm, Ralf; Dudzik, Esther; Valencia, Sergio [Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, 12489 Berlin (Germany); Mydosh, John A. [MPI-CPFS, 01187 Dresden (Germany); Kamerlingh Onnes Laboratory, Leiden University, 2300RA Leiden (Netherlands); Hermes, Wilfried; Poettgen, Rainer [Institut fuer Anorganische und Analytische Chemie, Universitaet Muenster, 48149 Muenster (Germany)

    2012-07-01

    At room temperature (RT), CeRuSn exhibits coexistence of trivalent Ce{sup 3+} and intermediate valent Ce{sup (4-{delta})+} in a metallic environment. Charge ordering produces a doubling of the unit cell along the c-axis with respect to the basic CeCoAl type structure. Below RT, a phase transition with broad hysteresis has been observed in various bulk properties. The present X-ray diffraction results show that at low temperatures the doubling of the CeCoAl type structure is replaced by an ill-defined modulated ground state in which at least three modulation periods compete. The dominant mode is close to a tripling of the basic cell. XANES data suggest that the average Ce valence remains constant. We propose a qualitative structure model with modified stacking sequences of Ce{sup 3+} and Ce{sup (4-{delta})+} layers in the various modulated phases. Surprisingly, far below 100 K the modulated state is sensitive to synchrotron X-ray irradiation. With a photon flux {approx} 10{sup 12} s{sup -1}, the modulated ground state is destroyed on a timescale of minutes and the doubling of the CeCoAl cell observed at room temperature is recovered. The final state is metastable at 10 K. Heating the sample above 60 K again leads to a recovery of the modulated state.

  9. Preparation,Characterization of CuO/CeO2 and Cu/CeO2 Catalysts and Their Applications in Low-Temperature CO Oxidation

    Institute of Scientific and Technical Information of China (English)

    Zheng Xiucheng; Han Dongzhan; Wang Shuping; Zhang Shoumin; Wang Shurong; Huang Weiping; Wu Shihua

    2005-01-01

    CeO2 was synthesized via sol-gel process and used as supporter to prepare CuO/CeO2, Cu/CeO2 catalysts by impregnation method. The catalytic properties and characterization of CeO2, CuO/CeO2 and Cu/CeO2 catalysts were examined by means of a microreactor-GC system, HRTEM, XRD, TPR and XPS techniques. The results show that CuO has not catalytic activity and the activity of CeO2 is quite low for CO oxidation. However, the catalytic activity of CuO/CeO2 and Cu/CeO2 catalysts increases significantly. Furthermore, the activity of CuO/CeO2 is higher than that of Cu/CeO2 catalysts.

  10. β-Cyclodextrin-assisted preparation of hierarchical walnut-like CeOHCO3 and CeO2 mesocrystals

    International Nuclear Information System (INIS)

    The hierarchical walnut-like CeOHCO3 mesocrystals were prepared by a facile hydrothermal method under low temperature with β-cyclodextrin (β-CD) as assistant agent. The hierarchical walnut-like CeO2 mesocrystals were obtained by thermal decomposition of CeOHCO3 mesocrystals. The crystal phase, morphology, and structure of CeOHCO3 and CeO2 mesocrystals were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and selected area electron diffraction (SAED). The time-dependent experimental results indicated that the morphology transformation from shuttle-like to walnut-like and the crystal phase transformation from orthorhombic to hexagonal simultaneously occurred in the formation processes of CeOHCO3 mesocrystals. On the basis of the morphological and crystal phase evolution processes, the formation mechanism of hierarchical walnut-like CeOHCO3 mesocrystals, including dissolution-recrystallization processes, was discussed. β-CD was believed to play an important role in the formation of the hierarchical walnut-like CeOHCO3 mesocrystals. The effects of reaction temperature, β-CD amount, and concentration of reactants on the morphologies of the products were systematically studied. CeO2 mesocrystals exhibited the distinct red-shift phenomenon in UV-vis absorption spectra.

  11. Thermodynamic stabilities of SrCeO3 and Sr2CeO4 using the fluoride EMF technique

    International Nuclear Information System (INIS)

    The standard Gibbs energies of formation of SrCeO3 and Sr2CeO4 were measured by the EMF method using CaF2 as a solid electrolyte. Three fluoride galvanic cells (I-III) were constructed in order to determine ΔfG deg. of SrCeO3. The ΔfG deg. of Sr2CeO4 was determined using galvanic cell (IV). The cells used were Pt,O2(g)(1bar),SrO(s),SrF2(s) vertical bar CaF2 vertical bar SrF2(s),CeO2(s),SrCeO3(s),O2(g) (1bar) (I); Pt,O2(g)(1bar),SrO(s),SrF2(s) vertical bar SrF2 vertical bar SrF2(s),CeO2(s),SrCeO3(s), O2(g)(1bar) (II); Pt,O2(g)(1bar),SrF2(s),CeO2(s),SrCeO3(s) vertical bar CaF2 vertical bar CaF2(s), CaO(s),O2(1bar) (III); Pt,O2(g)(1bar),SrO(s),SrF2(s) vertical bar CaF2 vertical bar SrF2(s),SrCeO3(s),Sr2CeO4(s),O2(1bar),Pt (IV). The standard Gibbs energy of formation of SrCeO3, derived from the mean of the EMFs of the above galvanic cells (I to III), is given by the following expression:ΔfG deg. (SrCeO3)+/-17(kJmol-1)=-1703+0.327T(K)(788-1142K) By combining this expression with the EMF measured using Cell IV, the following expression was obtained for the temperature dependence of the standard Gibbs energy of formation of Sr2CeO4ΔfG deg. (Sr2CeO4)+/-21(kJmol-1)=-2307+0.4400T(K)(805-1066K)

  12. Ce and T magnetism in CeTPO compounds (T = Os, Ru, Fe, Co) - large variety of ground states

    International Nuclear Information System (INIS)

    In the last years we have started a detailed investigation of the CeTPO compounds (T = Os, Ru, Fe, Co). These materials correspond to the family of LnTPnO systems, crystallizing in the tetragonal ZrCuSiAs structure-type, which attracts a lot of attention due the observation of high temperature superconductivity (SC) in the doped LnFeAsO compounds. Whereas the 3d-magnetism of the Fe is essentially for the occurrence of SC in LnFeAsO, the magnetism in CeTPO is dominated by the 4f-electrons of Ce3+. In this contribution, we summarize our results on the single crystal growth of the CeTPO materials together with a thorough physical characterization, including magnetization, susceptibility, resistivity, specific heat, and thermopower. These measurements reveal four different magnetic ground states: (1) CeRuPO is a rare example of a ferromagnetically ordered Kondo-lattice system with TC=15 K and a Kondo scale of TK∝10 K; (2) CeOsPO orders antiferromagnetically at TN=4.5 K; (3) CeFePO is a heavy-fermion system on the non-magnetic side of a ferromagnetic instability; (4) CeCoPO present ferromagnetic order of the Co-ions at TC=75 K and Ce-moments close to magnetism. Therefore, these new materials present a nice playground to study in detail the phenomena of strongly correlated electron systems.

  13. Neonatal Phosphate Nutrition Alters <em>in em>Vivo> and <em>in em>Vitro> Satellite Cell Activity in Pigs

    Directory of Open Access Journals (Sweden)

    Chad H. Stahl

    2012-05-01

    Full Text Available Satellite cell activity is necessary for postnatal skeletal muscle growth. Severe phosphate (PO4 deficiency can alter satellite cell activity, however the role of neonatal PO4 nutrition on satellite cell biology remains obscure. Twenty-one piglets (1 day of age, 1.8 ± 0.2 kg BW were pair-fed liquid diets that were either PO4 adequate (0.9% total P, supra-adequate (1.2% total P in PO4 requirement or deficient (0.7% total P in PO4 content for 12 days. Body weight was recorded daily and blood samples collected every 6 days. At day 12, pigs were orally dosed with BrdU and 12 h later, satellite cells were isolated. Satellite cells were also cultured <em>in vitroem> for 7 days to determine if PO4 nutrition alters their ability to proceed through their myogenic lineage. Dietary PO4 deficiency resulted in reduced (<em>P> < 0.05 sera PO4 and parathyroid hormone (PTH concentrations, while supra-adequate dietary PO4 improved (<em>P> < 0.05 feed conversion efficiency as compared to the PO4 adequate group. <em>In vivoem> satellite cell proliferation was reduced (<em>P> < 0.05 among the PO4 deficient pigs, and these cells had altered <em>in vitroem> expression of markers of myogenic progression. Further work to better understand early nutritional programming of satellite cells and the potential benefits of emphasizing early PO4 nutrition for future lean growth potential is warranted.

  14. Sn-CeO2 thin films prepared by rf magnetron sputtering: XPS and SIMS study

    International Nuclear Information System (INIS)

    Sn addition in the CeO2 thin film by simultaneous Sn metal and cerium oxide magnetron sputtering causes growth of Ce3+ rich films whilst pure cerium oxide sputtering provides stoichiometric CeO2 layers. Ce4+ → Ce3+ conversion is explained by a charge transfer from Sn atoms to unoccupied orbital Ce 4f0 of cerium oxide by forming Ce 4f1 state. XPS and SIMS revealed a formation of a new chemical Ce(Sn)+ state, which belongs to SnCeO2 species.

  15. Constituents from <em>Vigna em>vexillata> and Their Anti-Inflammatory Activity

    Directory of Open Access Journals (Sweden)

    Guo-Feng Chen

    2012-08-01

    Full Text Available The seeds of <em>Vigna em>genus are important food resources and there have already been many reports regarding their bioactivities. In our preliminary bioassay, the chloroform layer of methanol extracts of<em> V. vexillata em>demonstrated significant anti-inflammatory bioactivity. Therefore, the present research is aimed to purify and identify the anti-inflammatory principles of <em>V. vexillataem>. One new sterol (1 and two new isoflavones (2,3 were reported from the natural sources for the first time and their chemical structures were determined by the spectroscopic and mass spectrometric analyses. In addition, 37 known compounds were identified by comparison of their physical and spectroscopic data with those reported in the literature. Among the isolates, daidzein (23, abscisic acid (25, and quercetin (40 displayed the most significant inhibition of superoxide anion generation and elastase release.

  16. Synthesis and structural characterization of Ce-doped bismuth titanate

    International Nuclear Information System (INIS)

    Ce-modified bismuth titanate nanopowders Bi4-xCexTi3O12 (x ≤ 1) have been synthesized using a coprecipitation method. DTA/TG, FTIR, XRD, SEM/EDS and BET methods were used in order to investigate the effect of Ce-substitution on the structure, morphology and sinterability of the obtained powders. The phase structure investigation revealed that after calcinations at 600 deg. C powder without Ce addition exhibited pure bismuth titanate phase; however, powders with Ce (x = 0.25, 0.5 and 0.75) had bismuth titanate pyrochlore phase as the second phase. The strongest effect of Ce addition on the structure was noted for the powder with the highest amount of Ce (x = 1) having a cubic pyrochlore structure. The presence of pure pyrochlore phase was explained by its stabilization due to the incorporation of cerium ions in titanate structure. Ce-modified bismuth titanate ceramic had a density over 95% of theoretical density and the fracture in transgranular manner most probably due to preferable distribution of Ce in boundary region

  17. Biofunctionalization of CeF(3):Tb(3+) nanoparticles.

    Science.gov (United States)

    Kong, D Y; Wang, Z L; Lin, C K; Quan, Z W; Li, Y Y; Li, C X; Lin, J

    2007-02-21

    CeF(3):Tb(3+) nanoparticles (short pillar-like morphology with an average length and width of 11 and 5 nm, respectively) were successfully prepared by a polyol process using diethyleneglycol (DEG) as solvent. After being functionalized with a SiO(2)-NH(2) layer, these CeF(3):Tb(3+) nanoparticles can be conjugated with biotin molecules (activated by thionyl chloride) and further with avidin. The as-formed CeF(3):Tb(3+) nanoparticles, CeF(3):Tb(3+) nanoparticles functionalized with amino groups, biotin conjugated amino-functionalized CeF(3):Tb(3+) nanoparticles and biotinylated CeF(3):Tb(3+) nanoparticles bonded with avidin were characterized by x-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR), UV/vis absorption spectra and luminescence spectra, respectively. The biofunctionalization of the CeF(3):Tb(3+) nanoparticles has less effect on their luminescence properties, i.e. they still show strong green emission (from Tb(3+), with (5)D(4)-(7)F(5) at 543 nm as the most prominent group), indicative of the great potential for these CeF(3):Tb(3+) nanoparticles to be used as biological fluorescence probes. PMID:21730503

  18. Biofunctionalization of CeF3:Tb3+ nanoparticles

    Science.gov (United States)

    Kong, D. Y.; Wang, Z. L.; Lin, C. K.; Quan, Z. W.; Li, Y. Y.; Li, C. X.; Lin, J.

    2007-02-01

    CeF3:Tb3+ nanoparticles (short pillar-like morphology with an average length and width of 11 and 5 nm, respectively) were successfully prepared by a polyol process using diethyleneglycol (DEG) as solvent. After being functionalized with a SiO2-NH2 layer, these CeF3:Tb3+ nanoparticles can be conjugated with biotin molecules (activated by thionyl chloride) and further with avidin. The as-formed CeF3:Tb3+ nanoparticles, CeF3:Tb3+ nanoparticles functionalized with amino groups, biotin conjugated amino-functionalized CeF3:Tb3+ nanoparticles and biotinylated CeF3:Tb3+ nanoparticles bonded with avidin were characterized by x-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR), UV/vis absorption spectra and luminescence spectra, respectively. The biofunctionalization of the CeF3:Tb3+ nanoparticles has less effect on their luminescence properties, i.e. they still show strong green emission (from Tb3+, with 5D4-7F5 at 543 nm as the most prominent group), indicative of the great potential for these CeF3:Tb3+ nanoparticles to be used as biological fluorescence probes.

  19. Investigation of thermal neutron capture in 23Na, 138Ba, 140Ce and 142Ce

    International Nuclear Information System (INIS)

    A measurement of the angular correlation of γ-rays emitted in the capture of thermal neutrons in 23Na has been used to determine the multipole mixing ratio delta for seventeen transitions in 24Na, of which seven are primary transitions. For these primary transitions also the capture state spin admixture α has been derived. The neutron capture reaction proceeds predominantly through the Jsup(π)=1+ channel, as expected from previous cross-section measurements. A measurement of the circular polarization of γ-rays resulting from the capture of polarized thermal neutrons in 138Ba, 140Ce and 142Ce has yielded spin assignments for p-states in the final nuclei. Excitation energies and reaction Q-values have been obtained from the analysis of singles spectra taken with unpolarized neutrons. (Auth.)

  20. Collective excitations in {sup 132}Ce; Excitations collectives de {sup 132}Ce

    Energy Technology Data Exchange (ETDEWEB)

    Paul, E.S.; Boston, A.J.; Zoss, D.T.; Nolan, P.J.; Sampson, J.A.; Semple, A.T. [Oliver Lodge Laboratory, University of Livepool, Liverpool (United Kingdom); Farget, F.; Gizon, A.; Gizon, J.; Santos, D. [Inst. des Sciences Nucleaires, Grenoble-1 Univ., 38 (France); Nyako, B.M. [Institute of Nuclear Research, Debrecen (Hungary); O`Brien, N.J.; Parry, C.M.; Wadsworth, W. [Department of Physics, University of York, Helsington, York (United Kingdom)

    1997-12-31

    The structure of normally deformed states ({beta}{sub 2}{approx}0.2) in {sup 132}Ce has been investigated using EUROGAM2. Eight {Delta}I=2 bands and three {Delta}I=1 bands have been identified up to spin 40. The results are interpreted with the aid of Woods-Saxon cranking calculations which suggest a variety of triaxial shapes stabilized by specific active quasiparticle orbitals. (authors)

  1. Valence fluctuation in CeMo2Si2C

    International Nuclear Information System (INIS)

    Highlights: •Evidence for valence fluctuation of Ce ions. •XAS provides average formal LIII valence of Ce. •Kadowaki Woods ratio and Sommerfeld Wilson ratio indicate Fermi-liquid behavior. •DFT calculations reveal strong hybridization between Ce 4f and Mo 4d states. -- Abstract: We report on the valence fluctuation of Ce in CeMo2Si2C as studied by means of magnetic susceptibility χ(T), specific heat C(T), electrical resistivity ρ(T) and X-ray absorption spectroscopy. Powder X-ray diffraction revealed that CeMo2Si2C crystallizes in CeCr2Si2C-type layered tetragonal crystal structure (space group P4/mmm). The unit cell volume of CeMo2Si2C deviates from the expected lanthanide contraction, indicating non-trivalent state of Ce ions in this compound. The observed weak temperature dependence of the magnetic susceptibility and its low value indicate that Ce ions are in valence fluctuating state. The formal LIII Ce valence in CeMo2Si2C〈ν∼〉=3.14 as determined from X-ray absorption spectroscopy measurement is well below the value 〈ν∼〉≃3.4 in tetravalent Ce compound CeO2. The temperature dependence of specific heat does not show any anomaly down to 1.8 K which rules out any magnetic ordering in the system. The Sommerfeld coefficient obtained from the specific heat data is γ = 23.4 mJ/mol K2. The electrical resistivity follows the T2 behavior in the low temperature range below 35 K confirming a Fermi liquid behavior. Accordingly both the Kadowaki Woods ratio A/γ2 and the Sommerfeld Wilson ratio χ(0)/γ are in the range expected for Fermi-liquid systems. In order to get some information on the electronic states, we calculated the band structure within the density functional theory, eventhough this approach is not able to treat 4f electrons accurately. The non-f electron states crossing the Fermi level have mostly Mo 4d character. They provide the states with which the 4f sates are strongly hybridized, leading to the intermediate valent state

  2. CE APPROVAL IN ELECTRICAL HOUSEHOLD APPLIANCES AND A CASE STUDY

    Directory of Open Access Journals (Sweden)

    Nazmi EKREN

    2009-01-01

    Full Text Available Due to the reason for rapidly developing technology, increasing competition medium, and awareness of the consumers, nowadays, the exigency of production with good quality has gained more and more significance. Certification of the quality and safety of the products to the consumers is compulsory in terms of producers. There are some documents to certify safety of the products. One of them is CE certificate. In this paper, basic information about CE mark is given and CE standards and tests required for electrical household appliances are mentioned. As an application, one of an electrical household appliance, toaster grill is treated and examined. To obtain CE certificate for toaster grill, required tests are made according to EN60335-2-9 and CE certificate is obtained.

  3. Properties of LuAP: CE scintillator containing intentional impurities

    CERN Document Server

    Petrosyan, A G; Ovanesyan, K; Lecoq, Paul; Auffray, Etiennette; Trummer, Julia; Kronberger, Matthias; Pédrini, C; Dujardin, C; Anfre, P

    2007-01-01

    Single crystals of LuAP:Ce and LuYAP(Lu*70%):Ce co-doped with tetravalent (Hf and Zr) and pentavalent (Ta) ions were grown from melts by the Bridgman process. Underlying absorption, slope of the optical edge and transmission in the range of emission were compared to those of LuAP:Ce crystals. Absorption coefficients at 260 nm less than 2 cm−1 have been recorded in LuAP:Ce crystals containing tetravalent ions that are lower than the corresponding figures (5–6 cm−1) measured in undoped LuAP. At high concentrations of added impurities, despite of suppression of the parasitic underlying absorption below 300 nm, the slope of the optical edge and transmission in the range of emission are seriously damaged. Scintillation parameters of crystals with added impurities are compared to those of LuAP:Ce.

  4. Moment dilution in the heavy fermion compound Ce2Bi

    International Nuclear Information System (INIS)

    The heavy fermion compound Ce2Bi has two inequivalent Ce-sites. La was doped on these sites to study the influence of the antiferromagnetic order on the high electronic contribution of the specific heat (γHT(T>TN)∼340mJ/Ce-molK2). The slightly larger La atom replaces the Ce2 site first and then subsequently the Ce1 site in the La2Sb structure. Lattice parameters, magnetic susceptibility and specific heat are used to elucidate the magnetic nature of the two different cerium sites. We find a somewhat enhanced γHT, a decrease in TN and furthermore a metamagnetic transition at 2.2T (2K), which is closely related to the long-range antiferromagnetic order. ((orig.))

  5. Photodynamic Processes in Fluoride Crystals Doped with Ce3+

    Directory of Open Access Journals (Sweden)

    Pavlov V.V.

    2015-01-01

    Full Text Available Integrated studies of photoelectric phenomena and their associated photodynamic processes in LiCaAlF6, LiLuF4, LiYF4, LiY0,5Lu0,5F4, SrAlF5 crystals doped with Ce3+ ions have been carried out using the combination of the methods of optical and dielectric spectroscopy. The numerical values of the basic parameters of photodynamic processes and their spectral dependence in 240 – 310 nm spectral range are evaluated. It has been shown that the most probable process, which leads to the photoionization of Ce3+ ions in LiYxLu1-xF4:Ce3+ (x=0; 0,5; 1 and LiCaAlF6:Ce3+ crystals, is excited-state absorption to the states of mixed configurations of Ce3+ ions localized near/in the conduction band of crystal.

  6. The Antimicrobial Efficacy of <em>Elaeis guineensisem>: Characterization, <em>in Vitroem> and <em>in Vivoem> Studies

    Directory of Open Access Journals (Sweden)

    Sreenivasan Sasidharan

    2012-04-01

    Full Text Available The urgent need to treat multi-drug resistant pathogenic microorganisms in chronically infected patients has given rise to the development of new antimicrobials from natural resources. We have tested <em>Elaeis guineensis em>Jacq> em>(Arecaceae methanol extract against a variety of bacterial, fungal and yeast strains associated with infections. Our studies have demonstrated that <em>E. guineensisem> exhibits excellent antimicrobial activity <em>in vitroem> and <em>in vivoem> against the bacterial and fungal strains tested. A marked inhibitory effect of the <em>E. guineensisem> extracts was observed against <em>C. albicansem> whereby <em>E. guineensisem> extract at ½, 1, or 2 times the MIC significantly inhibited <em>C. albicansem> growth with a noticeable drop in optical density (OD of the bacterial culture. This finding confirmed the anticandidal activity of the extract on <em>C. albicansem>. Imaging using scanning (SEM and transmission (TEM electron microscopy was done to determine the major alterations in the microstructure of the extract-treated <em>C. albicansem>. The main abnormalities noted via SEM and TEM studies were the alteration in morphology of the yeast cells. <em>In vivoem> antimicrobial activity was studies in mice that had been inoculated with <em>C. albicansem> and exhibited good anticandidal activity. The authors conclude that the extract may be used as a candidate for the development of anticandidal agent.<em> em>

  7. Evaluation of Pseudopteroxazole and Pseudopterosin Derivatives against <em>Mycobacterium> <em>tuberculosis> and Other Pathogens

    Directory of Open Access Journals (Sweden)

    Malcolm W. B. McCulloch

    2012-08-01

    Full Text Available Pseudopterosins and pseudopteroxazole are intriguing marine natural products that possess notable antimicrobial activity with a commensurate lack of cytotoxicity. New semi-synthetic pseudopteroxazoles, pseudopteroquinoxalines and pseudopterosin congeners along with simple synthetic mimics of the terpene skeleton were synthesized. In order to build structure-activity relationships, a set of 29 new and previously reported compounds was assessed for <em>in> <em>vitro> antimicrobial and cytotoxic activities. A number of congeners exhibited antimicrobial activity against a range of Gram-positive bacteria including <em>Mycobacterium> <em>tuberculosis> H37Rv, with four displaying notable antitubercular activity against both replicating and non-replicating persistent forms of <em>M.> <em>tuberculosis>. One new semi-synthetic compound, 21-((1<em>H>-imidazol-5-ylmethyl-pseudopteroxazole (7a, was more potent than the natural products pseudopterosin and pseudopteroxazole and exhibited equipotent activity against both replicating and non-replicating persistent forms of <em>M.> <em>tuberculosis> with a near absence of <em>in> <em>vitro> cytotoxicity. Pseudopteroxazole also exhibited activity against strains of <em>M.> <em>tuberculosis> H37Rv resistant to six clinically used antibiotics.

  8. Ordering of CeIII/CeIV and interstitial oxygens in CeTaO4+x (x ∼ 0.17) superstructure

    International Nuclear Information System (INIS)

    A structural model for CeTaO4+x (x ∼ 0.17) or alternately Ce4IIICe2IVTa6O25 (monoclinic, P21, a = 7.616(2), b = 16.459(5), c = 7.704(2) angstrom, β = 102.48(2)degree, Z = 2) is derived from X-ray powder diffraction data. The starting model was a 3 x b superstructure of CeTaO4+x (x = 0.0) with excess oxygen atoms occupying interstices between the Ce atom layers consistent with the electron diffraction determined space group symmetry P21. Unexpectedly, the four Ce atoms surrounding the interstitial oxygen are not oxidized. During the refinement the model was forced to be chemically plausible by restraining bond valence sums, bond lengths, and O-O distances. This was necessary due to the very weak scattering contribution to the XRD profile by oxygen atoms. The mechanism for oxidation of the subject phase from CeTaO4+x (x = 0.0) is discussed and a reason for the limiting composition for this phase is proposed

  9. Enthalpies of mixing in binary Fe-Sb, Ce-Fe and ternary Ce-Fe-Sb liquid alloys

    Energy Technology Data Exchange (ETDEWEB)

    Usenko, Natalia; Kotova, Natalia [Taras Shevchenko National Univ., Kyiv (Ukraine). Dept. of Chemistry; Ivanov, Michael; Berezutski, Vadim [National Academy of Sciences, Kyiv (Ukraine). I. Frantsevich Institute for Problems of Materials Science

    2016-01-15

    The enthalpies of mixing in liquid alloys in the binary Fe-Sb, Ce-Fe and ternary Ce-Fe-Sb systems were determined over a wide range of composition by means of isoperibolic calorimetry in the temperature range 1600-1830 K. The minimum values of the integral enthalpy of mixing (ΔH{sub min}) were determined to be (-2.32 ± 0.22) kJ . mol{sup -1} at x{sub Sb} = 0.5 in the Fe-Sb system, and (-0.97 ± 0.19) kJ . mol{sup -1} at x{sub Ce} = 0.35 in the Ce-Fe system. The enthalpies of mixing in liquid ternary Ce-Fe-Sb alloys were found to increase smoothly from the binary boundary systems Ce-Fe and Fe-Sb towards the Ce-Sb system, reaching the minimum value of (-107.5 ± 3.6) kJ . mol{sup -1} in the vicinity of the phase CeSb.

  10. Structural and electronic properties of Ce overlayers and low-dimensional Pt-Ce alloys on Pt{111}

    International Nuclear Information System (INIS)

    The structural, thermal, chemisorptive, and electronic properties of Ce on Pt{111} are studied by photoemission, Auger spectroscopy, scanning tunnel microscope (STM), and low-energy electron diffraction (LEED). Stranski-Krastanov-like growth of low-density Ce layers is accompanied by substantial valence charge transfer from Ce to Pt: in line with this, the measured dipole moment and polarizability of adsorbed Ce at low coverages are 7.2x10-30Cm and ∼1.3x10-29m3, respectively. Pt-Ce intermixing commences at ∼400K and with increasing temperature a sequence of five different ordered surface alloys evolves. The symmetry, periodicities, and rotational epitaxy observed by LEED are in good accord with the STM data which reveal the true complexity of the system. The various bimetallic surface phases are based on growth of crystalline Pt5Ce, a hexagonal layer structure consisting of alternating layers of Pt2Ce and Kagomacute e nets of Pt atoms. This characteristic ABAB layered arrangement of the surface alloys is clearly imaged, and chemisorption data permit a distinction to be made between the more reactive Pt2Ce layer and the less reactive Pt Kagomacute e net. Either type of layer can appear at the surface as the terminating structure, thicker films exhibiting unit mesh parameters characteristic of the bulk alloy. copyright 1997 The American Physical Society

  11. Ce4+/Ce3+-V2+/V3+氧化还原流动电池的可行性研究(Ⅱ)--旋转圆盘(RDE)与旋转环盘(RRDE)法对Ce4+/Ce3+氧化还原体系的研究%Studies on Feasibility of Ce4+/Ce3+ - V2+/V3+ Redox Flow Cell ( Ⅱ ) --Investigation of Ce4 +/Ce3 + Redox System by RDE and RRDE

    Institute of Scientific and Technical Information of China (English)

    夏熙; 刘洋; 刘洪涛

    2001-01-01

    用RDE与REDE法研究了Ce4+/Ce3+-V2+/V3+氧化还原流动电池中Ce4+/Ce3+体系的电化学动力学参数,以说明组成该新型氧化还原流动电池的可能性.用RDE法得出在铂电极表面与玻碳电极上均会生成一层氧化膜,对Ce3+的氧化反应产生阻碍作用.但在铂上的氧化膜对Ce4+的还原反应却有催化作用.用Rrde法得出Ce3+在玻碳电极上的氧化与析氧之间存在着竞争,为得到较高的Ce3+氧化效率,应控制氧化电流在2~8 mA@cm-2之间.

  12. Efficient Heterologous Transformation of <em>Chlamydomonas> reinhardtiiem> <em>npq2em> Mutant with the Zeaxanthin Epoxidase Gene Isolated and Characterized from<em> Chlorella zofingiensisem>

    Directory of Open Access Journals (Sweden)

    Herminia Rodríguez

    2012-09-01

    Full Text Available In the violaxanthin cycle, the violaxanthin de-epoxidase and zeaxanthin epoxidase catalyze the inter-conversion between violaxanthin and zeaxanthin in both plants and green algae. The zeaxanthin epoxidase gene from the green microalga <em>Chlorella zofingiensisem> (<em>Czzep> has been isolated<em>. em>This gene encodes a polypeptide of 596 amino acids. A single copy of <em>Czzep> has been found in the <em>C. zofingiensisem> genome by Southern blot analysis. qPCR analysis has shown that transcript levels of <em>Czzep> were increased after zeaxanthin formation under high light conditions. The functionality of <em>Czzep> gene by heterologous genetic complementation in the <em>Chlamydomonas> mutant <em>npq2em>, which lacks zeaxanthin epoxidase (ZEP activity and accumulates zeaxanthin in all conditions, was analyzed. The <em>Czzep> gene was adequately inserted in the pSI105 vector and expressed in <em>npq2em>. The positive transformants were able to efficiently convert zeaxanthin into violaxanthin, as well as to restore their maximum quantum efficiency of the PSII (Fv/Fm. These results show that <em>Chlamydomonas> can be an efficient tool for heterologous expression and metabolic engineering for biotechnological applications.

  13. The formation of intermetallic compounds during interdiffusion of Mg–Al/Mg–Ce diffusion couples

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Jiahong [College of Materials Science and Engineering, National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044 (China); Jiang, Bin, E-mail: jiangbinrong@cqu.edu.cn [College of Materials Science and Engineering, National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044 (China); Chongqing Academy of Science and Technology, Chongqing 401123 (China); Li, Xin [College of Materials Science and Engineering, National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044 (China); Yang, Qingshan [College of Materials Science and Engineering, National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044 (China); Chongqing Academy of Science and Technology, Chongqing 401123 (China); Dong, Hanwu [Chongqing Academy of Science and Technology, Chongqing 401123 (China); Xia, Xiangsheng [No. 59 Institute of China Ordnance Industry, Chongqing 400039 (China); Pan, Fusheng [College of Materials Science and Engineering, National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044 (China); Chongqing Academy of Science and Technology, Chongqing 401123 (China)

    2015-01-15

    Graphical abstract: Al–Ce intermetallic compounds (IMCs) formed in Mg–Al/Mg–Ce diffusion couples. During the whole diffusion process, Al was the dominant diffusing species, and it substituted for Mg atoms of the Mg–Ce substrate. Five Al–Ce IMCs of Al{sub 4}Ce, Al{sub 11}Ce{sub 3}, Al{sub 3}Ce, Al{sub 2}Ce, and AlCe were formed via the reaction of Al and Ce. - Highlights: • Al–Ce IMCs formation in the Mg–Al/Mg–Ce diffusion couples was studied. • Formation of Al{sub 4}Ce as the first phase was rationalized using the Gibbs free energy. • The activation energy for the growth of the diffusion reaction zones was 36.6 kJ/mol. - Abstract: The formation of Al–Ce intermetallic compounds (IMCs) during interdiffusion of Mg–Al/Mg–Ce diffusion couples prepared by solid–liquid contact method was investigated at 623 K, 648 K and 673 K for 24 h, 48 h and 72 h, respectively. During the whole diffusion process, Al was the dominant diffusing species, and it substituted for Mg of the Mg–Ce substrate. Five Al–Ce IMCs of Al{sub 4}Ce, Al{sub 11}Ce{sub 3}, Al{sub 3}Ce, Al{sub 2}Ce and AlCe were formed via the reaction of Al and Ce. The formation of Al{sub 4}Ce as the first kind of IMC was rationalized on the basis of an effective Gibbs free energy model. The activation energy for the growth of the total diffusion reaction layer was 36.6 kJ/mol.

  14. Characterizations of electrodeposited Ni–CeO2 nanocomposite coatings

    International Nuclear Information System (INIS)

    The expansion of current machinery requires metallic materials with better surface properties. In the present investigation, CeO2 reinforced nickel nanocomposite coatings were deposited on mild steel substrate by direct current electrodeposition process employing nickel acetate bath. The effect of incorporation of CeO2 particles in the Ni nanocomposite coatings on the micro hardness and corrosion behaviour has been evaluated. Smooth and compact nanocomposite deposits containing well-distributed cerium oxide particles were obtained. The crystallite structure was fcc for electrodeposited nickel and Ni–CeO2 nanocomposite coatings. It has been observed that, the presence of CeO2 nanoparticles favours the [111] and [200] texture of nickel matrix. The co-deposition of CeO2 nanoparticles with nickel was found to be favoured at applied current density of 8 A dm−2. The micro hardness values of the nickel nanocomposite coatings (725 HV) was higher than that of pure nickel (265 HV).The decrease in Icorr values and increase in Constant Phase Element values were investigated in 3.5% NaCl solution which showed the higher corrosion resistant nature of Ni–CeO2 coatings. - Highlights: • Ni–CeO2 composite coatings have electrodeposited from eco-friendly acetate bath. • Inclusion of CeO2 in the composite coating has refined the crystallite size. • Micro hardness values have increased with CeO2 content in the composite coatings. • The negative shift of Ecorr confirming cathodic protective nature of coatings

  15. Groundwater fluctuations and footslope ferricrete soils in the humid tropical zone of southern Cameroon

    Science.gov (United States)

    Temgoua, Emile; Djeuda Tchapnga, Henri-Bosko; Tanawa, Emile; Guenat, Claire; Pfeifer, Hans-Rudolf

    2005-10-01

    This paper discusses the relationship between the differentiation of ferruginous accumulations and the variable water saturation of footslope soil patterns. An analysis of the slope morphology of a typical hill in the forest zone of southern Cameroon and a seasonal survey of the levels of groundwaters, springs and rivers were considered in relation to the petrology of different soil patterns. The study site is a tabular hillock whose slopes present a progressive development from steep to gentle slopes. The variable residence time of water within the soil, creating an alternation of reducing and oxidizing conditions, affects soil chemistry, structure and lateral extension of the soil patterns. The ferruginous soil patterns, being formed on the footslopes, gradually increase in extent with decreasing slope angle and the relative rise of the groundwater level. The steep footslopes, where groundwater has a shorter residence time, show a soft mottled clay pattern, restricted to the bottom part of the slope. The moderate footslopes exhibit a deep permanent and a temporary perched groundwater table. The latter, with its regular capillary fringe, contributes to more reducing conditions within isolated domains in the soil patterns, and thus to the alternation with oxidizing conditions, generating a continuous hard soil pattern (massive carapace). The more gently dipping footslopes exhibit groundwater levels near the surface and also a significant amplitude of groundwater fluctuation. Iron, previously accumulated in moderate footslope patterns, is reduced, remobilized, and leached. The soil patterns formed develop into a variegated carapace, more extended along the slope, containing less iron, but nevertheless more hardened, due to the important fluctuations of the groundwater table. These patterns are limited to the zone of groundwater fluctuation and deteriorate as the water fluctuation zone recedes.

  16. Exotic clustering in Ce and Nd isotopes

    CERN Document Server

    Buck, B; Pérez, S M

    1999-01-01

    We propose exotic binary cluster models for the intermediate mass nuclei sup 1 sup 4 sup 6 sup , sup 1 sup 4 sup 8 sup , sup 1 sup 5 sup 0 Ce and sup 1 sup 4 sup 8 sup , sup 1 sup 5 sup 0 sup , sup 1 sup 5 sup 2 sup , sup 1 sup 5 sup 4 Nd. The optimum choice of cluster and core is determined by joint consideration of the penetrability for exotic cluster emission, the deviations of cluster and core binding energies from underlying liquid drop values and the Q-values for breakup. It is noticeable that the core neutron number selected in this way is at or near the N = 82 shell closure. We use a standard form of the cluster-core potential to calculate the energies and wave functions of states in the ground 0 sup + , 2 sup + , 4 sup + , ... and lowest lying negative parity 1 sup - , 3 sup - , 5 sup - , ... bands. The theoretical spectra and electromagnetic properties are compared with measurements, and their general trends are reproduced satisfactorily.

  17. CE-merkityn murskeen tuottaminen rakennusurakan sivutuottena - kannattavuusselvitys

    OpenAIRE

    Komulainen, Ville

    2014-01-01

    Työssä tutkittiin murskatun kiviaineksen CE-merkintäperusteita sekä mitä tuotannollisia sekä laadullisia vaatimuksia kiviainestuotannolle CE-merkintä edellyttää. Lisäksi tutkittiin, onko mahdollista saada CE-merkityn kiviaineksen tuotanto ISO 9001 -standardin sisältävän laadunhallintajärjestelmän alle ja voiko tuotanto olla osa kyseistä laadunhallintajärjestelmää. Työ tehdään Graniittirakennus Kallio Oy:lle. Tuotannon kannattavuusselvityksen osalta tutkittiin eri tuotantomalleja, mikä on ...

  18. Template electrosynthesis of CeO2 nanotubes

    International Nuclear Information System (INIS)

    Nanotube arrays of CeO2 were produced in a single step by potentiostatic electrochemical deposition from a non-aqueous electrolyte, using anodic alumina membrane templates. The CeO2 nanotubes showed a polycrystalline structure, and they were assembled in the membrane nanochannels. The nanotubes had somewhat uniform diameters, with an average external value of about 210 nm, and a maximum length of about 60 μm; the latter parameter was controlled by the electrodeposition time. Each single nanotube was found to consist of crystalline grains having a size of about 3 nm. Raman analysis shows that these CeO2 nanotubes are suitable for catalytic applications

  19. Non-Fermi Liquid Scaling in CeRhSn

    International Nuclear Information System (INIS)

    We have recently shown that CeRhSn exhibits non-Fermi liquid temperature dependences in its low-temperature physical properties. Here we suggest that the non-Fermi liquid behavior observed in CeRhSn may be due to the existence of a Griffiths phase in the vicinity of a quantum critical point, based on electrical resistivity, magnetic susceptibility , and specific heat measurements. For CeRhSn, the low-temperature scaling of bulk properties (C/T ∝ χ ∝ T-1+λ, where λ<1) is masked by an anomaly at about 6 K, which is of magnetic origin. (author)

  20. Growth of LGSO: Ce crystals by the Czochralski method

    International Nuclear Information System (INIS)

    Single crystals of Lu2xGd2-2xSiO5: Ce (0 1/c to C2/c in the course of substitution of lutetium for gadolinium occurs at the ratio Lu/(Lu + Gd) = 0.1. The lattice thus formed with symmetry C2/c in the structure of Lu2xGd2-2xSiO5: Ce crystals favors the maximum possible incorporation of Ce3+ ions into the sevenfold-coordinated position with respect to oxygen. This explains the substantial improvement of the scintillation characteristics of the grown crystals.

  1. Properties and practical application of thin CeOx films

    Directory of Open Access Journals (Sweden)

    Maksimchuk N. V.

    2010-10-01

    Full Text Available The properties of CeOx films produced by various methods have been investigated. According to the comparative analisys “metallic mirror oxidation” method allows to produce films with significantly better characteristics than the «explosive evaporation» method. Though the latter method yields higher photosensitivity of CeOx films and structures on their base. In the process the optimal value of the substrate temperature was determined. Obtained data expand the CeOx application potential in microelectronic sensor sphere.

  2. A unique CE16 acetyl esterase from Podospora anserina active on polymeric xylan.

    Science.gov (United States)

    Puchart, Vladimír; Berrin, Jean-Guy; Haon, Mireille; Biely, Peter

    2015-12-01

    The genome of the coprophilous fungus Podospora anserina displays an impressive array of genes encoding hemicellulolytic enzymes. In this study, we focused on a putative carbohydrate esterase (CE) from family 16 (CE16) that bears a carbohydrate-binding module from family CBM1. The protein was heterologously expressed in Pichia pastoris and purified to electrophoretic homogeneity. The P. anserina CE16 enzyme (PaCE16A) exhibited different catalytic properties than so far known CE16 esterases represented by the Trichoderma reesei CE16 acetyl esterase (TrCE16). A common property of both CE16 esterases is their exodeacetylase activity, i.e., deesterification at positions 3 and 4 of monomeric xylosides and the nonreducing end xylopyranosyl (Xylp) residue of oligomeric homologues. However, the PaCE16A showed lower positional specificity than TrCE16 and efficiently deacetylated also position 2. The major difference observed between PaCE16A and TrCE16 was found on polymeric substrate, acetylglucuronoxylan. While TrCE16 does not attack internal acetyl groups, PaCE16A deacetylated singly and doubly acetylated Xylp residues in the polymer to such an extent that it resulted in the polymer precipitation. Similarly as typical acetylxylan esterases belonging to CE1, CE4, CE5, and CE6 families, PaCE16A did not attack 3-O-acetyl group of xylopyranosyl residues carrying 4-O-methyl-D-glucuronic acid at position 2. PaCE16A thus represents a CE16 member displaying unique catalytic properties, which are intermediate between the TrCE16 exodeacetylase and acetylxylan esterases designed to deacetylate polymeric substrate. The catalytic versatility of PaCE16A makes the enzyme an important candidate for biotechnological applications. PMID:26329850

  3. Reference Gene Selection in the Desert Plant <em>Eremosparton songoricuem>m>

    OpenAIRE

    Dao-Yuan Zhang; Yuan-Ming Zhang; Wood, Andrew J.; Xiao-Shuang Li; Hong-Lan Yang

    2012-01-01

    <em>Eremosparton songoricum em>(Litv.) Vass. (<em>E. songoricumem>) is a rare and extremely drought-tolerant desert plant that holds promise as a model organism for the identification of genes associated with water deficit stress. Here, we cloned and evaluated the expression of eight candidate reference genes using quantitative real-time reverse transcriptase polymerase chain reactions. The expression of these candidate reference genes was analyzed in a diverse set...

  4. HumanViCe: Host ceRNA network in virus infected cells in human

    Directory of Open Access Journals (Sweden)

    Suman eGhosal

    2014-07-01

    Full Text Available Host-virus interaction via host cellular components has been an important field of research in recent times. RNA interference mediated by short interfering RNAs and microRNAs (miRNA, is a widespread anti-viral defence strategy. Importantly, viruses also encode their own miRNAs. In recent times miRNAs were identified as key players in host-virus interaction. Furthermore, viruses were shown to exploit the host miRNA networks to suite their own need. The complex cross-talk between host and viral miRNAs and their cellular and viral targets forms the environment for viral pathogenesis. Apart from protein-coding mRNAs, non-coding RNAs may also be targeted by host or viral miRNAs in virus infected cells, and viruses can exploit the host miRNA mediated gene regulatory network via the competing endogenous RNA effect. A recent report showed that viral U-rich non-coding RNAs called HSUR, expressed in primate virus herpesvirus saimiri (HVS infected T cells, were able to bind to three host miRNAs, causing significant alteration in cellular level for one of the miRNAs. We have predicted protein coding and non protein-coding targets for viral and human miRNAs in virus infected cells. We identified viral miRNA targets within host non-coding RNA loci from AGO interacting regions in three different virus infected cells. Gene ontology (GO and pathway enrichment analysis of the genes comprising the ceRNA networks in the virus infected cells revealed enrichment of key cellular signalling pathways related to cell fate decisions and gene transcription, like Notch and Wnt signalling pathways, as well as pathways related to viral entry, replication and virulence. We identified a vast number of non-coding transcripts playing as potential ceRNAs to the immune response associated genes; e.g. APOBEC family genes, in some virus infected cells. All these information are compiled in HumanViCe, a comprehensive database that provides the potential ceRNA networks in virus

  5. Optical properties of CeNi{sub 5} and CeNi{sub 4}M (M = Al, Cu) compounds

    Energy Technology Data Exchange (ETDEWEB)

    Knyazev, Yu. V., E-mail: knyazev@imp.uran.ru [Institute of Metal Physics, Ural Division, RAS, 18 Kovalevskaya St., 620990 Ekaterinburg (Russian Federation); Kuz' min, Yu. I.; Kuchin, A.G. [Institute of Metal Physics, Ural Division, RAS, 18 Kovalevskaya St., 620990 Ekaterinburg (Russian Federation)

    2011-01-21

    The experimental study of the optical properties of CeNi{sub 5}, CeNi{sub 4}Cu and CeNi{sub 4}Al compounds was carried out in the 0.083-5.64 eV energy range using the ellipsometry method. The optical constants, dielectric functions and electronic parameters (plasma and relaxation frequencies) were determined. The energy dependencies of the optical interband conductivities are discussed by using the available information on the electronic band structure of these compounds. In the ternary alloys the optical spectra show the presence of peculiarities related to effect of Cu or Al substitution at Ni sites.

  6. Optical properties of CeNi5 and CeNi4M (M = Al, Cu) compounds

    International Nuclear Information System (INIS)

    The experimental study of the optical properties of CeNi5, CeNi4Cu and CeNi4Al compounds was carried out in the 0.083-5.64 eV energy range using the ellipsometry method. The optical constants, dielectric functions and electronic parameters (plasma and relaxation frequencies) were determined. The energy dependencies of the optical interband conductivities are discussed by using the available information on the electronic band structure of these compounds. In the ternary alloys the optical spectra show the presence of peculiarities related to effect of Cu or Al substitution at Ni sites.

  7. Highly Enhanced Concentration and Stability of Reactive Ce^3+ on Doped CeO_2 Surface Revealed In Operando

    OpenAIRE

    Chueh, William C.; McDaniel, Anthony H.; Grass, Michael E.; Hao, Yong; Jabeen, Naila; Liu, Zhi; Haile, Sossina M.; McCarty, Kevin F.; Bluhm, Hendrik; El Gabaly, Farid

    2012-01-01

    Trivalent cerium ions in CeO_2 are the key active species in a wide range of catalytic and electro-catalytic reactions. We employed ambient pressure X-ray photoelectron spectroscopy and electrochemical impedance spectroscopy to quantify simultaneously the concentration of the reactive Ce^3+ species on the surface and in the bulk of Sm-doped CeO_2(100) in hundreds of millitorr of H2–H2O gas mixtures. Under relatively oxidizing conditions, when the bulk cerium is almost entirely in the 4+ oxida...

  8. Using LaBr3(Ce) Detectors for Precision Lifetime Measurements of Excited States in `Interesting' Nuclei

    Science.gov (United States)

    Regan, P. H.

    2015-11-01

    Precision measurements of electromagnetic transition rates provide accurate inputs into nuclear data evaluations and are also used to test and validate predictions of state of the art nuclear structure models. Measurements of transition rates can be used to ascertain or rule out multipolarity assignments for the measured EM decay, thereby providing spin- and parity-difference information for states between which the EM transition takes place. This conference paper reports on a measurements of electromagnetic transition rates between excited nuclear states using coincidence `fast-timing' gamma-ray spectroscopy with cerium-doped, lanthanum-tribromide (LaBr3(Ce)) detectors. Examples of recent precision measurements using a combined LaBr3-HpGe array based at the tandem accelerator, Bucharest, Romania include studies around the N=20 and N=82 shell closures using stable-beam induced fusion-evaporation reactions; and the evolution of nuclear deformation around in neutron-rich Hf, W and Os nuclei using 7Li-induced light-ion transfer reactions. This paper also presents the ongoing development of a new multidetector LaBr3(Ce) array for future studies of exotic nuclei produced at the upcoming Facility for Anti-Proton and Ion Research (FAIR) as part of the NUSTAR-DESPEC project, and reports on the pre-NUSTAR implementations of detectors from this array to study electromagnetic transition rates in neutron-rich fission fragments at ILL-Grenoble, France and RIBF at RIKEN, Japan.

  9. Three-Dimensional Structure of CeO2 Nanocrystals

    DEFF Research Database (Denmark)

    Tan, Joyce Pei Ying; Tan, Hui Ru; Boothroyd, Chris;

    2011-01-01

    Visualization of three-dimensional (3D) structures of materials at the nanometer scale can shed important information on the performance of their applications and provide insight into the growth mechanism of shape-controlled nanomaterials. In this paper, the 3D structures and growth pathway of CeO2...... samples synthesized under different conditions. The homogeneous growth environment in solution with polyvinylpyrrolidone (PVP) molecules led to the formation of regular octahedral CeO2 nanocrystals with small {001} facet truncations. When the PVP surfactant was removed, the aggregation of regular...... truncated octahedral CeO2 particles through a lattice matched interface generated irregular compressed truncated octahedral CeO2 nanoparticles. The formation of this irregular shape is attributed to the lower surface diffusion and slow incorporation of atoms on surfaces by step attachment of the fused...

  10. Performance evaluation of LaBr3: Ce scintillator

    International Nuclear Information System (INIS)

    The cerium doped lanthanum bromide crystal (LaBr3: Ce) is a new kind of scintillator with many advantages such as good energy resolution, high light output, short decay time, good proportionality response. These properties make the LaBr3: Ce attractive substantial interest to use in the radiation detection. The energy resolution were investigated with Φ25 × 25 mm LaBr3: Ce coupled to a Hamamatsu R8900 photomultiplier tube. Energy resolution of 3.6% (FWHM) have been achieved for 511 keV photons (18F source) at room temperature. Decay time constant of 20 ns have been acquired with a Hamamatsu fast-time-response R9800 photomultiplier tube. The results approve the excellent characterizations of LaBr3: Ce and imply its enormous potentiality in the radiation detectors of gamma-ray spectroscopy and PET. (authors)

  11. O- centers in LuAG:Ce,Mg ceramics

    International Nuclear Information System (INIS)

    Electron traps are known to a have great influence on the carriers transport process in Ce based scintillators. On the other hand, the role of hole traps in the scintillation process has been less considered. By means of electron spin resonance (ESR), we detected hole traps in highly Ce-doped LuAG:Ce,Mg ceramics in the form of σ-type O- centers. The g -tensor components turn out to be g perpendicular to = 2.0103, and g parallel = 2.0023, revealing the axial symmetry of these defects. Mg-perturbed variants of O- centers are proposed to exist in LuAG:Ce,Mg. Their occurrence is related to an elongated Mg-O bond as evidenced by DFT calculations. Finally, the multiple role of O- centers in the scintillation process is discussed. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  12. Nuclear structure of 130-136Ce in IBM-1

    International Nuclear Information System (INIS)

    The level structure of Ce isotopes with N < 82 has been studied in recent experiments, yielding increasing information on the non yrast bands. The Interacting Boson Model (IBM-1) offers a useful tool for such phenomenological study

  13. Thermoelectric Properties of Nanostructured CeAl3

    Science.gov (United States)

    Pokharel, Mani; Dahal, Tulashi; Ren, Zhifeng; Opeil, Cyril; Opeil Group Team; Ren Group Team

    2014-03-01

    Past investigations into the heavy fermion compound CeAl3 reveal a complex low-temperature physics resulting from the strong hybridization of localized 4f states with delocalized conduction electrons. This phenomenon gives rise to unusual electronic, thermal, and magnetic properties. We investigate the low-temperature thermoelectric properties of this strongly correlated system for its potential application as a p-type Peltier cooling element. In our work, nanostructured samples of CeAl3 have been prepared using dc hot-press method and evaluated for their thermoelectric properties. Effects of different hot-pressing temperatures on the nanostructure and the thermoelectric properties will be discussed. Our results on CeAl3 will be compared with our previous work on CeCu6. Funding for this work was provided by the DOD, USAF-OSR, MURI Program under Contract FA9550-10-1-0533.

  14. Analyzing input/output subsystem security in Windows CE

    OpenAIRE

    Pereira, Barbara A.

    2001-01-01

    In the past few years, mobile handheld devices have emerged as an exciting new tool for accomplishing everyday tasks. Devices with the Windows CE operating system provide flexibility for the designer in the form of customizable modules and components. With wireless capabilities and a familiar user interface, Windows CE devices are becoming popular for such tasks as inventory control and information retrieval. By enhancing the self-protection of the operating system, handheld devices could be ...

  15. EM International. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    1993-07-01

    It is the intent of EM International to describe the Office of Environmental Restoration and Waste Management`s (EM`s) various roles and responsibilities within the international community. Cooperative agreements and programs, descriptions of projects and technologies, and synopses of visits to international sites are all highlighted in this semiannual journal. Focus on EM programs in this issue is on international collaboration in vitrification projects. Technology highlights covers: in situ sealing for contaminated sites; and remote sensors for toxic pollutants. Section on profiles of countries includes: Arctic contamination by the former Soviet Union, and EM activities with Germany--cooperative arrangements.

  16. Cerocene Revisited: The Electronic Structure of and Interconversion Between Ce2(C8H8)3 and Ce(C8H8)2

    Energy Technology Data Exchange (ETDEWEB)

    Walter, Marc D.; Booth, Corwin H.; Lukens, Wayne W.; Andersen, Richard A.

    2009-02-02

    New synthetic procedures for the preparation of Ce(cot)2, cerocene, from [Li(thf)4][Ce(cot)2], and Ce2(cot)3 in high yield and purity are reported. Heating solid Ce(cot)2 yields Ce2(cot)3 and COT while heating Ce2(cot)3 with an excess of COT in C6D6 to 65oC over four months yields Ce(cot)2. The solid state magnetic susceptibility of these three organocerium compounds shows that Ce(cot)2 behaves as a TIP (temperature independent paramagnet) over the temperature range of 5-300 K, while that of Ce2(cot)3 shows that the spin carriers are antiferromagnetically coupled below 10 K; above 10 K, the individual spins are uncorrelated, and [Ce(cot)2]- behaves as an isolated f1 paramagnet. The EPR at 1.5K for Ce2(cot)3 and [Ce(cot)2]- have ground state of MJ= +- 1/2. The LIII edge XANES of Ce(cot)2 (Booth, C.H.; Walter, M.D.; Daniel, M.; Lukens, W.W., Andersen, R.A., Phys. Rev. Lett. 2005, 95, 267202) and 2Ce2(cot)3 over 30-500 K are reported; the Ce(cot)2 XANES spectra show Ce(III) and Ce(IV) signatures up to a temperature of approximately 500 K, whereupon the Ce(IV) signature disappears, consistent with the thermal behavior observed in the melting experiment. The EXAFS of Ce(cot)2 and Ce2(cot)3 are reported at 30 K; the agreement between the molecular parameters for Ce(cot)2 derived from EXAFS and single crystal X-ray diffraction data are excellent. In the case of Ce2(cot)3 no X-ray diffraction data are known to exist, but the EXAFS are consistent with a"triple-decker" sandwich structure. A molecular rationalization is presented for the electronic structure of cerocene having a multiconfiguration ground state that is an admixture of the two configurations Ce(III, 4f1)(cot1.5-)2 and Ce(IV, 4f0)(cot2-)2; the multiconfigurational ground state has profound effects on the magnetic properties and on the nature of the chemical bond in cerocene and, perhaps, other molecules.

  17. CeO2 nanoparticles for high performance supercapacitor electrode

    International Nuclear Information System (INIS)

    Cerium Oxide plays a vital role in rising technologies for energy-related applications. In this study, CeO2 nanoparticles have been successfully synthesized by microwave irradiation method and its capacitance performance is further investigated. Prepared nanoparticles were analysed by X-Ray Powder Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). X-ray diffraction analysis confirms that CeO2 Nanoparticles in cubic phase and the grain size was calculated to be 15 nm using Debye-Scherrer formula. The FTIR spectrum of the CeO2 exhibits the stretching vibration of Ce-O at about 601 cm-1. The SEM analysis shows the irregular spherical morphology with some of the particles agglomerated. Electrochemical characterization of the sample was performed using a standard three electrode cell configuration. Cyclic Voltammogram (CV) and galvanostatic (GV) charge-discharge measurements demonstrated that the CeO2 electrode exhibited superior capacitive properties in 1 M Na2SO4 aqueous solution within the potential range -0.2V to 1.5V The discharge curves are linear in the total range of potential with constant slopes at a constant current of 0.9 A/g showing perfect capacitive behavior. These findings can open up new opportunities for CeO2 nanoparticles in constructing the high-performance electrochemical supercapacitors as well as other energy storage devices. (author)

  18. International EMS Systems

    DEFF Research Database (Denmark)

    Langhelle, Audun; Lossius, Hans Morten; Silfvast, Tom;

    2004-01-01

    . Access to on-line medical advice of a physician is not available; (2) Finland: the autonomy of the individual municipalities and their responsibility to cover for primary and specialised health care, as well as the EMS, and the lack of supporting or demanding legislation regarding the EMS; (3) Iceland is...... the only country that has emergency medicine (EM) as a recognised speciality but there is a need for more fully trained specialists in EM; (4) Norway: the ordinary ground ambulance is pointed out as the weakest link in the EM chain and a health reform demands extensive co-operation between the new...... health enterprises to re-establish a nation-wide air ambulance service; (5) Sweden: to create evidence based medicine standards for treatment in emergency medicine, a better integration of all part of the chain of survival, a formalised education in EM and a nation wide physician staffed helicopter EMS...

  19. Características agronômicas do amendoinzeiro sob irrigação com águas salinas em solo com biofertilizantes.

    OpenAIRE

    Sousa, Geocleber Gomes de; de Azevedo, Benito Moreira; Albuquerque, André Henrique Pinheiro; Mesquita, José Bruno Rego de; Viana, Thales Vinicius de Araújo

    2012-01-01

    Objetivou-se com esse trabalho avaliar o efeito da salinidade da água de irrigação nas características agronômicas do amendoinzeiro (Arachis hypogaea L.) cultivado em solo sem e com biofertilizantes. O experimento foi conduzido em estufa telada na Estação Agrometereológica, Campus do Pici, Fortaleza, CE. A semeadura foi feita em vasos utilizando-se, como substrato, um Argissolo Vermelho-Amarelo, com uma planta por vaso. O experimento obedeceu a um delineamento inteiramente casualizado, em esq...

  20. Structural and optical study of Ce segregation in Ce-doped SiO{sub 1.5} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Beainy, G.; Castro, C.; Pareige, P.; Talbot, E., E-mail: etienne.talbot@univ-rouen.fr [Groupe de Physique des Matériaux, Université et INSA de Rouen, UMR CNRS 6634, Normandie Université, Avenue de l' Université, BP 12, 76801 St Etienne du Rouvray (France); Weimmerskirch-Aubatin, J.; Stoffel, M.; Vergnat, M.; Rinnert, H. [Université de Lorraine, UMR CNRS 7198, Institut Jean Lamour, BP 70239, 54506 Vandoeuvre-lès-Nancy (France)

    2015-12-21

    Cerium doped SiO{sub 1.5} thin films fabricated by evaporation and containing silicon nanocrystals were investigated by atom probe tomography. The effect of post-growth annealing treatment has been systematically studied to correlate the structural properties obtained by atom probe tomography to the optical properties measured by photoluminescence spectroscopy. The atom probe results demonstrated the formation of Ce-Si rich clusters upon annealing at 900 °C which leads to a drastic decrease of the Ce-related luminescence. At 1100 °C, pure Si nanocrystals and optically active cerium silicate compounds are formed. Consequently, the Ce-related luminescence is found to re-appear at this temperature while no Si-nanocrystal related luminescence is observed for films containing more than 3% Ce.

  1. Optical properties of LaF3:Ce and LaF3:Ce, Tb embedded polymer nanocomposites

    International Nuclear Information System (INIS)

    Colloidal solutions containing LaF3:Ce and LaF3:Ce,Tb nanoparticles were synthesized and embedded in polyacrylamide through a simple procedure. Very fine colloidal nanoparticle suspension in dm-water was synthesized by adopting co-precipitation technique in acidic environment. Nanoparticles were characterized for their crystal structure, particle size, UV-ViS absorption and photoluminescence behavior using X-ray diffraction, DLS, and photoluminescence spectroscopy techniques respectively. Size of nano-crystals was estimated using the Scherer formula. The life time measurements of the colloidal solutions were done. The transparent polymer nano composites containing LaF3:Ce and LaF3:Ce, Tb exhibited emissions at 304 and 490, 543, 585, 622 nm respectively. The colloidal route for polymer nanocomposite synthesis seems to be an easy and effective way to fabricate optically transparent photo-luminescent composite materials in variety of sizes and shapes. (author)

  2. Precariedade do trabalho e da vida de catadores de recicláveis em Fortaleza, CE

    Directory of Open Access Journals (Sweden)

    Regina Heloisa Maciel

    2011-10-01

    Full Text Available The article discusses life and work conditions of young, middle-aged and elderly street pickers, focusing on experiences of childhood, adolescence and actual job. Eight workers, between 20 and 85 years of age, men and women, were interviewed. The data indicates that: all had a childhood and adolescence marked by lack of resources and emotional support, early insertion in precarious work and low education; the current work maintains the previous experiences of precarious living and working conditions and lack of prospects of inclusion in the formal work market; young workers express feelings of hopelessness and failure; middle-aged and older workers managed to build a safety net through associations of recyclable collectors; all participants reported they have to deal with bigotry revealed in the eyes "of others" for whom a collector is "garbage", "beggar, vulture", a possible "thief". Finally, all believe the work is critical to their and their families' survival and is a "right" job.

  3. Electro-regeneration of Ce(IV) in real spent Cr-etching solutions.

    Science.gov (United States)

    Chen, Te-San; Huang, Kuo-Lin

    2013-11-15

    This paper presents the electro-regeneration of Ce(IV) in real (hazardous) spent thin-film transistor liquid-crystal display (TFT-LCD) Cr-etching solutions. In addition to Ce(III)>Ce(IV) in diffusivity, a quasi-reversible behavior of Ce(III)/Ce(IV) was observed at both boron-doped diamond (BDD) and Pt disk electrodes. The Ce(IV) yield on Pt increased with increasing current density, and the best current efficiency (CE) was obtained at 2A/2.25 cm(2). The performance in terms of Ce(IV) yield and CE of tested anodes was in order BDD>Pt>dimensional stable anode (DSA). At 2A/2.25 cm(2) on Pt and 40 °C for 90 min, the Ce(IV) yield, CE and apparent rate constant (k) for Ce(III) oxidation were 81.4%, 21.8% and 3.17 × 10(-4) s(-1), respectively. With the increase of temperature, the Ce(IV) yield, CE, and k increased (activation energy = 10.7 kJ/mol), but the specific electricity consumption decreased. The Neosepta CMX membrane was more suitable than Nafion-117 and Nafion-212 to be used as the separator of the Ce(IV) regeneration process. The obtained parameters are useful to design divided batch reactors for the Ce(IV) electro-regeneration in real spent Cr-etching solutions. PMID:24140527

  4. Non-Stoichiometry of UO2-CeO2: The System UO2-CeO2-CeO1.5 at 900 to 1200°C

    International Nuclear Information System (INIS)

    This investigation covers the substoichiometric fluorite (UO2-CeO2) phase, that is, the behaviour of the system U1-yCe1-yO2+x. Though UO2 and CeO2 are completely miscible, and in the CeO2-CeO1-5 system the fluorite phase extends to CeO1.72 , the UO2-CeO2-CeO1.5 system is characterized by a large two-phase region, where two fluorite- type structures, one CeO2-rich, the other UO2-rich, coexist. Only in the UO2-rich corner of the ternary system is a noticeable single-phase region present. This is in contrast to the CeO2-UO2-UO267 system where a large single-phase region exists. The oxygen activity as a function of composition x was measured in U1-yCe1-yO2+x (y = 0.15 and 0.35) at 900°C, using H2/H2O and metal/metal oxide equilibria. In all cases the oxygen activity increases extremely rapidly with decreasing x; the behaviour of the system resembles that of dilute solutions of UO2+X in ThO2. Both systems can be explained by assuming defect complexes: a vacancy bound to two Ce3+, an interstitial oxygen bound to two U5+. (author)

  5. The CE3R Network: current status and future perspectives

    Science.gov (United States)

    Lenhardt, Wolfgang; Pesaresi, Damiano; Živčić, Mladen; Costa, Giovanni; Kuk, Kresimir; Bondár, István; Duni, Llambro; Spacek, Petr

    2016-04-01

    In order to improve the monitoring of seismic activities in the border regions and to enhance the collaboration between countries and seismological institutions in Central Europe, the Environment Agency of the Slovenian Republic (ARSO), the Italian National Institute for Oceanography and Experimental Geophysics (OGS), the University of Trieste (UniTS) and the Austrian Central Institute for Meteorology and Geodynamics (ZAMG) established in 2001 the "South Eastern Alps Transfrontier Seismological Network". In May 2014 ARSO, OGS, UniTS and ZAMG agreed to formalize the transfrontier network, to name it "Central and East European Earthquake Research Network", (CE3RN or CE3R Network) in order to locate it geographically since cross-border networks can be established in other areas of the world and to expand their cooperation, including institutions in other countries. The University of Zagreb (UniZG) joined CE3RN in October 2014. The Kövesligethy Radó Seismological Observatory (KRSZO) of the Hungarian Academy of Sciences joined CE3RN in October 2015. The Institute of Geosciences, Energy, Water and Environment (IGEWE) of the Polytechnic University of Tirana joined CE3RN in November 2015. The Institute of Physics of the Earth (IPE) of the Masaryk University in Brno joined CE3RN in November 2015. CE3RN Parties intend to formalize and possibly extend their ongoing cooperation in the field of seismological data acquisition, exchange and use for seismological and earthquake engineering and civil protection purposes. The purpose of this cooperation is to retain and expand the existing cross-border network, specify the rules of conduct in the network management, improvements, extensions and enlargements, enhance seismological research in the region, and support civil protection activities. Since the formal establishment of CE3RN, several common projects have been completed, like the SeismoSAT project for the seismic data center connection over satellite funded by the Interreg

  6. Electroless ternary NiCeP coatings: Preparation and characterisation

    International Nuclear Information System (INIS)

    Highlights: ► Rare earth element (Ce) has been successfully codeposited in NiP matrix. ► Surface analysis carried out by XPS showed that the Ce is present in +3 and +4 oxidation state. ► Palladium stability test indicated that the Ce salts in electroless nickel bath has reduced the stability. ► Cerium codeposition in NiP matrix has increased the microhardness both in as-plated and annealed conditions. ► Higher thermal stability has been obtained by Ce incorporation. - Abstract: Electroless ternary NiCeP deposits were prepared from alkaline citrate bath containing nickel sulphate, cerium chloride and sodium hypophosphite. Concentration of rare earth cerium was varied from 1 to 2 g/L to obtain ternary deposits containing variable Ce and P contents. The influence of cerium on the deposit properties was analysed. The deposit exhibited a maximum cerium content of 6.2 ± 0.1 wt.% when the cerium chloride concentration was 2 g/L. The result of the Pd stability test showed that the stability of the bath was reduced due to Ce salt addition. The microhardness measurements made on both as-plated and heat treated samples exhibited a peak hardness of 1006 ± 11 VHN for cerium concentration of 1.5 g/L. The concept of kinetic strength analysis was proved to be applicable only for binary and not for ternary alloys due to multistep deposition mechanism with different kinetic energies. X-ray diffraction (XRD) patterns of as-plated and heat treated samples revealed peaks corresponding to Ni (1 1 1) and nickel phosphide (Ni3P). Higher amount of Ce incorporation in NiP matrix increased the crystallisation temperature of the deposit which could be due to the suppression of nickel crystallisation prior to Ni3P compound formation and thus increasing the activation energy for the formation of stable phases. Surface compositional analysis using X-ray photoelectron spectroscopy (XPS) carried out on as-plated NiCeP-2 deposit showed a prominent peak of P existing in +1 oxidation

  7. Electroless ternary NiCeP coatings: Preparation and characterisation

    Energy Technology Data Exchange (ETDEWEB)

    Balaraju, J.N., E-mail: jnbalraj@nal.res.in [Surface Engineering Division, CSIR National Aerospace Laboratories, Post Bag No. 1779 Bangalore 560017, Karnataka (India); Chembath, Manju [Surface Engineering Division, CSIR National Aerospace Laboratories, Post Bag No. 1779 Bangalore 560017, Karnataka (India)

    2012-10-01

    Highlights: Black-Right-Pointing-Pointer Rare earth element (Ce) has been successfully codeposited in NiP matrix. Black-Right-Pointing-Pointer Surface analysis carried out by XPS showed that the Ce is present in +3 and +4 oxidation state. Black-Right-Pointing-Pointer Palladium stability test indicated that the Ce salts in electroless nickel bath has reduced the stability. Black-Right-Pointing-Pointer Cerium codeposition in NiP matrix has increased the microhardness both in as-plated and annealed conditions. Black-Right-Pointing-Pointer Higher thermal stability has been obtained by Ce incorporation. - Abstract: Electroless ternary NiCeP deposits were prepared from alkaline citrate bath containing nickel sulphate, cerium chloride and sodium hypophosphite. Concentration of rare earth cerium was varied from 1 to 2 g/L to obtain ternary deposits containing variable Ce and P contents. The influence of cerium on the deposit properties was analysed. The deposit exhibited a maximum cerium content of 6.2 {+-} 0.1 wt.% when the cerium chloride concentration was 2 g/L. The result of the Pd stability test showed that the stability of the bath was reduced due to Ce salt addition. The microhardness measurements made on both as-plated and heat treated samples exhibited a peak hardness of 1006 {+-} 11 VHN for cerium concentration of 1.5 g/L. The concept of kinetic strength analysis was proved to be applicable only for binary and not for ternary alloys due to multistep deposition mechanism with different kinetic energies. X-ray diffraction (XRD) patterns of as-plated and heat treated samples revealed peaks corresponding to Ni (1 1 1) and nickel phosphide (Ni{sub 3}P). Higher amount of Ce incorporation in NiP matrix increased the crystallisation temperature of the deposit which could be due to the suppression of nickel crystallisation prior to Ni{sub 3}P compound formation and thus increasing the activation energy for the formation of stable phases. Surface compositional analysis

  8. Effects of CeO2 Support Facets on VOx/CeO2 Catalysts in Oxidative Dehydrogenation of Methanol

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yan; Wei, Zhehao; Gao, Feng; Kovarik, Libor; Peden, Charles HF; Wang, Yong

    2014-05-13

    CeO2 supports with dominating facets, i.e., low index (100), (110) and (111) facets, are prepared. The facet effects on the structure and catalytic performance of supported vanadium oxide catalysts are investigated using oxidative dehydrogenation of methanol as a model reaction. In the presence of mixed facets, Infrared and Raman characterizations demonstrate that surface vanadia species preferentially deposit on CeO2 (100) facets, presumably because of its higher surface energy. At the same surface vanadium densities, VOx species on (100) facets show better dispersion, followed by (110) and (111) facets. The VOx species on CeO2 nanorods with (110) and (100) facets display higher activity and lower apparent activation energies compared to that on CeO2 nanopolyhedras with dominating (111) facets and CeO2 nanocubes with dominating (100) facets. The higher activity for VOx/CeO2(110) might be related to the more abundant oxygen vacancies present on the (110) facets, evidenced from Raman spectroscopic measurements.

  9. Testes de capacidade de expansão em programas de melhoramento de milho pipoca Popping expansion tests in popcorn breeding programs

    OpenAIRE

    Frederico de Pina Matta; José Marcelo Soriano Viana

    2001-01-01

    No desenvolvimento de populações melhoradas de milho pipoca é fundamental selecionar com base em qualidade, normalmente expressa pela relação volume de pipoca/peso de grãos, denominada capacidade de expansão (CE). Na seleção de indivíduos e progênies diversos sistemas de avaliação de qualidade devem ser considerados, por serem utilizados pelos consumidores. O propósito deste trabalho foi avaliar dois sistemas de determinação de CE em programas de melhoramento, sendo o primeiro uma pipoqueira ...

  10. Ce que Foucault a appris de Bentham

    Directory of Open Access Journals (Sweden)

    Christian Laval

    2011-05-01

    Full Text Available Michel Foucault, à plusieurs reprises et sous différents angles, a dit ce qu’il devait à Jeremy Bentham, considéré comme le principal « technologue » de la société disciplinaire. Mais Foucault est beaucoup plus qu’un lecteur  de Bentham. Il doit être regardé sur certains points comme un héritier théorique inavoué et sur d’autres comme un interprète  original de son œuvre et de sa place dans l’histoire des formes et des conceptions politiques. La conception foucaldienne du pouvoir comme structuration d’un  certain champ d’action rappelle immanquablement les considérations de Bentham sur « l’influence », sur la « méthode oblique »  et sur la « législation indirecte » par lesquelles on peut orienter le comportement des sujets. D’autre part, la distinction qu’il opère entre « souveraineté » et  « gouvernementalité »   permet de considérer d’une nouvelle façon l’originalité théorique et historique de l’auteur du Fragment sur le gouvernement. Le concept foucaldien de biopolitique en est un parfait exemple.Michel Foucault insisted in several instances, and in several ways, on what he owed Jeremy Bentham, the main “technologist” of disciplinary societies. But Foucault did not only read Bentham: he must be regarded as, on the one hand, an unacknowledged disciple, and on the other, an original interpreter of his work and his role in the history of political forms and concepts. Foucault’s understanding of power as the structuring of a field of action cannot fail to recall Bentham’s views on “influence” and on “indirect legislation” as means of channelling the subjects’ behaviour. Elsewhere, his distinction between “sovereignty” and “governmentality” allows us to cast a fruitful retrospective look on the thought of the author of the Fragment on Government. Foucault’s concept of “biopolitics” provides a perfect example.

  11. International EMS Systems

    DEFF Research Database (Denmark)

    Langhelle, Audun; Lossius, Hans Morten; Silfvast, Tom;

    2004-01-01

    Emergency medicine service (EMS) systems in the five Nordic countries have more similarities than differences. One similarity is the involvement of anaesthesiologists as pre-hospital physicians and their strong participation for all critically ill and injured patients in-hospital. Discrepancies do....... Access to on-line medical advice of a physician is not available; (2) Finland: the autonomy of the individual municipalities and their responsibility to cover for primary and specialised health care, as well as the EMS, and the lack of supporting or demanding legislation regarding the EMS; (3) Iceland...... is the only country that has emergency medicine (EM) as a recognised speciality but there is a need for more fully trained specialists in EM; (4) Norway: the ordinary ground ambulance is pointed out as the weakest link in the EM chain and a health reform demands extensive co-operation between the new health...

  12. SELF-ASSEMBLY CE OXIDE/ORGANOPOLYSILOXANE COMPOSITE COATINGS.

    Energy Technology Data Exchange (ETDEWEB)

    SUGAMA,T.; SABATINI,R.; GAWLIK,K.

    2005-01-01

    A self-assembly composite synthesis technology was used to put together a Ce(OH){sub 3}-dispersed poly-acetamide-acetoxyl methyl-propylsiloxane (PAAMPA) organometallic polymer. Three spontaneous reactions were involved; condensation, amidation, and acetoxylation, between the Ce acetate and aminopropylsilane triol (APST) at 150 C. An increase in temperature to 200 C led to the in-situ phase transformation of Ce(OH){sub 3} into Ce{sub 2}O{sub 3} in the PAAMPA matrix. A further increase to 250 C caused oxidative degradation of the PAAMPA, thereby generating copious fissures in the composite. We assessed the potential of Ce(OH){sub 3}/ and Ce{sub 2}O{sub 3}/ PAAMPA composite materials as corrosion-preventing coatings for carbon steel and aluminum. The Ce{sub 2}O{sub 3} composite coating displayed better performance in protecting both metals against NaCl-caused corrosion than did the Ce(OH){sub 3} composite. Using this coating formed at 200 C, we demonstrated that the following four factors played an essential role in further mitigating the corrosion of the metals: First was a minimum susceptibility of coating's surface to moisture; second was an enhanced densification of the coating layer; third was the retardation of the cathodic oxygen reduction reaction at the metal's corrosion sites due to the deposition of Ce{sub 2}O{sub 3} as a passive film over the metal's surface; and, fourth was its good adherence to metals. The last two factors contributed to minimizing the cathodic delamination of coating film from the metal's surface. We also noted that the affinity of the composite with the surface of aluminum was much stronger than that with steel. Correspondingly, the rate of corrosion of aluminum was reduced as much as two orders of magnitude by a nanoscale thick coating. In contrast, its ability to reduce the corrosion rate of steel was lower than one order of magnitude.

  13. Comparison of energy structure and spectral properties of Ce:LaAlO3 and Ce:Lu2(SiO4)O

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Undoped LaAlO3 and 1 at.%Ce:LaAlO3 single crystals were grown by the Czochralski process.Absorption and fluorescence spectra were measured at room temperature.Detailed energy levels structure of Ce:LaAlO3 was determined.In this paper,two viewpoints were provided.The first one is:the energy levels structure of Ce:LaAlO3 is very similar to that of Ce:Lu2(SiO4)O which is a well-known scintillator.In the energy levels structure of Ce:LaAlO3 and Ce:Lu2(SiO4)O,the lowest 5d energy level of Ce 3+ is located below the bottom of the conduction band of host crystal and the other higher 5d energy levels of Ce 3+ are located above the bottom of the conduction band of host crystal.The second one is:Ce:LaAlO3 single crystal may not be suitable for scintillation application;by comparing the energy levels structures of Ce:LaAlO3 and Ce:Lu2(SiO4)O,the large energy difference(1.13 eV)between the two lowest 5d energy levels of Ce 3+ in LaAlO3 is a crucial factor that causes the luminescence quenching.

  14. An Update on NiCE Support for BISON

    Energy Technology Data Exchange (ETDEWEB)

    McCaskey, Alex [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Billings, Jay Jay [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Deyton, Jordan H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Wojtowicz, Anna [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-09-01

    The Nuclear Energy Advanced Modeling and Simulation program (NEAMS) from the Department of Energy s Office of Nuclear Energy has funded the development of a modeling and simulation workflow environment to support the various codes in its nuclear energy scientific computing toolkit. This NEAMS Integrated Computational Environment (NiCE) provides extensible tools and services that enable efficient code execution, input generation, pre-processing visualizations, and post-simulation data analysis and visualization for a large portion of the NEAMS Toolkit. A strong focus for the NiCE development team throughout FY 2015 has been support for the Multiphysics Object Oriented Simulation Environment (MOOSE) and the NEAMS nuclear fuel performance modeling application built on that environment, BISON. There is a strong desire in the program to enable and facilitate the use of BISON throughout nuclear energy research and industry. A primary result of this desire is the need for strong support for BISON in NiCE. This report will detail improvements to NiCE support for BISON. We will present a new and improved interface for interacting with BISON simulations in a variety of ways: (1) improved input model generation, (2) embedded mesh and solution data visualizations, and (3) local and remote BISON simulation launch. We will also show how NiCE has been extended to provide support for BISON code development.

  15. Levels in 146Ce and the N = 88 isotones

    International Nuclear Information System (INIS)

    An investigation of the level structure of 146Ce following the beta decay of the low-spin isomer of 146La has been carried out at the ISOL facility TRISTAN at Brookhaven National Laboratory. The half-life for the low spin isomer was found to be 6.0 +- 0.4s. A partial level scheme for 146Ce below 2 MeV is given. The level energies and some B(E2) values extracted from our data have been compared with IBA-2 calculations done entirely with extrapolated parameters from neighboring Z nuclei in order to check the predictive power of the model. Systematics of the Z = 58 isotopes and N = 88 isotones indicate that although 146Ce is more deformed than its isotones with Z >= 60, the transition to the well-deformed region can probably more correctly be thought to occur after 146Ce, between N = 88 and N = 90, as it does for Z >= 60. The abrupt onset of deformation present in the higher Z isotopes is not seen in the Ce isotopes where the trend is found to be rather smooth throughout. (orig.)

  16. Isolation and Characterization of a Lycopene ε-Cyclase Gene of <em>Chlorella em>(Chromochloris> <em>zofingiensis>. Regulation of the Carotenogenic Pathway by Nitrogen and Light

    Directory of Open Access Journals (Sweden)

    Maria Angeles Vargas

    2012-09-01

    Full Text Available The isolation and characterization of the lycopene ε-cyclase gene from the green microalga <em>Chlorella em>(Chromochloris> <em>zofingiensis> (<em>Czlcy-e> was performed. This gene is involved in the formation of the carotenoids α-carotene and lutein. <em>Czlcy-e> gene encoded a polypeptide of 654 amino acids. A single copy of <em>Czlcy-e> was found in <em>C. zofingiensisem>. Functional analysis by heterologous complementation in <em>Escherichia coliem> showed the ability of this protein to convert lycopene to δ-carotene. In addition, the regulation of the carotenogenic pathway by light and nitrogen was also studied in <em>C. zofingiensisem>. High irradiance stress did not increase mRNA levels of neither lycopene β<em>->cyclase gene (<em>lcy-b> nor lycopene ε-cyclase gene<em> em>(lcy-e> as compared with low irradiance conditions, whereas the transcript levels of <em>psy>, <em>pds>, <em>chyB> and <em>bkt> genes were enhanced, nevertheless triggering the synthesis of the secondary carotenoids astaxanthin, canthaxanthin and zeaxanthin and decreasing the levels of the primary carotenoids α-carotene, lutein, violaxanthin and β-carotene. Nitrogen starvation <em>per seem> enhanced mRNA levels of all genes considered, except <em>lcy-e and pdsem>, but did not trigger the synthesis of astaxanthin, canthaxanthin nor zeaxanthin. The combined effect of both high light and nitrogen starvation stresses enhanced significantly the accumulation of these carotenoids as well as the transcript levels of <em>bkt> gene, as compared with the effect of only high irradiance stress.

  17. Photoluminescence, and scintillation/thermoluminescence yields of several Ce3+ and Eu2+ activated borates

    International Nuclear Information System (INIS)

    Powder samples of the borates YBO3 : Ce3+, GdBO3 : Ce3+, Li6Y(BO3)3 : Ce3+, LaB3O6 : Ce3+, GdB3O6 : Ce3+, LaMgB5O10 : Ce3+, YMgB5O10 : Ce3+, CaLaB7O13 : Ce3+, CaLaB7O13 : Eu2+, Ca4YO(BO3)3 : Ce3+ and CaYOBO3 : Eu2+ were studied. The photoluminescence properties of Ce3+ in these compounds are discussed and some of them are reported for the first time. The scintillation light yield of the orthoborates YBO3 : Ce3+, GdBO3 : Ce3+, ScBO3 : Ce3+ and YAl3B4O12 : Ce3+ is of the order of 10,000 pho/MeV. The light yield due to Ce3+ in the other borates is an order of magnitude lower. In LaB3O6 : Ce3+ and LaMgB5O10 : Ce3+ a broad emission band, attributed to self-trapped exciton (STE) emission, is observed under X-ray excitation. The STE light yield of LaB3O6 : Ce3+ (0.05%) is 8000 pho/MeV and it is quenched at higher Ce concentrations. Thermoluminescence measurements show that none of these materials has a potential to be utilized as a thermal neutron storage phosphor

  18. Emergency Medical Service (EMS) Stations

    Data.gov (United States)

    Kansas Data Access and Support Center — EMS Locations in Kansas The EMS stations dataset consists of any location where emergency medical services (EMS) personnel are stationed or based out of, or where...

  19. Mixed cerium-platinum oxides: Electronic structure of [CeO]Ptn (n = 1, 2) and [CeO2]Pt complex anions and neutrals.

    Science.gov (United States)

    Ray, Manisha; Kafader, Jared O; Topolski, Josey E; Jarrold, Caroline Chick

    2016-07-28

    The electronic structures of several small Ce-Pt oxide complexes were explored using a combination of anion photoelectron (PE) spectroscopy and density functional theory calculations. Pt and Pt2 both accept electron density from CeO diatomic molecules, in which the cerium atom is in a lower-than-bulk oxidation state (+2 versus bulk +4). Neutral [CeO]Pt and [CeO]Pt2 complexes are therefore ionic, with electronic structures described qualitatively as [CeO(+2)]Pt(-2) and [CeO(+)]Pt2 (-), respectively. The associated anions are described qualitatively as [CeO(+)]Pt(-2) and [CeO(+)]Pt2 (-2), respectively. In both neutrals and anions, the most stable molecular structures determined by calculations feature a distinct CeO moiety, with the positively charged Ce center pointing toward the electron rich Pt or Pt2 moiety. Spectral simulations based on calculated spectroscopic parameters are in fair agreement with the spectra, validating the computationally determined structures. In contrast, when Pt is coupled with CeO2, which has no Ce-localized electrons that can readily be donated to Pt, the anion is described as [CeO2]Pt(-). The molecular structure predicted computationally suggests that it is governed by charge-dipole interactions. The neutral [CeO2]Pt complex lacks charge-dipole stabilizing interactions, and is predicted to be structurally very different from the anion, featuring a single Pt-O-Ce bridge bond. The PE spectra of several of the complexes exhibit evidence of photodissociation with Pt(-) daughter ion formation. The electronic structures of these complexes are related to local interactions in Pt-ceria catalyst-support systems. PMID:27475371

  20. Crystal structure of the CeIr3 compound

    International Nuclear Information System (INIS)

    The crystal structure of the CeIr3 compound was refined for the first time from single-crystal X-ray diffraction data, down to R=0.0490, wR2=0.1052. This compound crystallizes in the PuNi3 structure type, space group R3-bar m (a=5.290(2) A, c=26.220(4) A, Z=9, V=635.44 A3, ρ=16.835 g cm-3, μ=156.36 mm-1). CeIr3 belongs to the R2m+nM4m+5n family, where m and n are the numbers of MgCu2- and CaCu5-type slabs, respectively. For CeIr3, m and n were found to be both equal to 1

  1. Transverse wobbling motion in $^{134}$Ce and $^{136}$Nd

    CERN Document Server

    Petrache, C M

    2016-01-01

    The existence of one-phonon and possible two-phonon transverse wobbling bands is proposed for the first time in two even-even nuclei, $^{134}$Ce and $^{136}$Nd. The predominant $E2$ character of the $\\Delta I = 1$ transitions connecting the one-phonon wobbling band in $^{134}$Ce to the two-quasiparticle yrast band supports the wobbling interpretation. The extracted wobbling frequencies decrease with increasing spin, indicating the transverse character of the wobbling motion, with the angular momenta of the two quasiparticles aligned perpendicular to the axis of collective rotation. A candidate for two-phonon wobbling motion is also proposed in $^{136}$Nd. The wobbling frequencies calculated in the harmonic frozen approximation are in good agreement with the experimental ones for both the$^{134}$Ce and $^{136}$Nd nuclei.

  2. Performance Evaluation of CE-OFDM in PLC Channel

    Directory of Open Access Journals (Sweden)

    El ghzaoui Mohammed, Belkadid Jamal, Benbassou Ali

    2011-02-01

    Full Text Available One major drawback associated with an OFDM system is that the transmitter’soutput signal may have a high peak-to-average ratio (PAPR. High levels of PARmay be a limiting factor for power line communication (PLC where regulatorybodies have fixed the maximum amount of transmit power. To overcome thisproblem, many approaches have been presented in the literature. One potentialsolution for reducing the peak-to-average power ratio (PAPR in an OFDMsystem is to utilize a constant envelope OFDM (CE-OFDM system. This paperdescribes a CE-OFDM based modem for Power Line Communications (PLCover the low voltage distribution network. The impact of the electrical applianceson the signal transmission is investigated. The good performances of the BERhave been checked by the simulation platform of real PLC channel using Matlab.Finally, CE-OFDM-CPM is compared with conventional OFDM under HomePlugAV..

  3. Performance Evaluation of CE-OFDM in PLC Channel

    Directory of Open Access Journals (Sweden)

    El Ghzaoui Mohammed

    2011-02-01

    Full Text Available One major drawback associated with an OFDM system is that the transmitter’s output signal may have a high peak-to-average ratio (PAPR. High levels of PAR may be a limiting factor for power line communication (PLC where regulatory bodies have fixed the maximum amount of transmit power. To overcome this problem, many approaches have been presented in the literature. One potential solution for reducing the peak-to-average power ratio (PAPR in an OFDM system is to utilize a constant envelope OFDM (CE-OFDM system. This paper describes a CE-OFDM based modem for Power Line Communications (PLC over the low voltage distribution network. The impact of the electrical appliances on the signal transmission is investigated. The good performances of the BER have been checked by the simulation platform of real PLC channel using Matlab. Finally, CE-OFDM-CPM is compared with conventional OFDM under HomePlug AV.

  4. Homoleptic Ce(III) and Ce(IV) Nitroxide Complexes: Significant Stabilization of the 4+ Oxidation State

    Energy Technology Data Exchange (ETDEWEB)

    Bogart, Justin A.; Lewis, Andrew J.; Medling, Scott A.; Piro, Nicholas A.; Carroll, Patrick J.; Booth, Corwin H.; Schelter, Eric J.

    2014-06-25

    Electrochemical experiments performed on the complex Ce-IV[2-((BuNO)-Bu-t)py](4), where [2-((BuNO)-Bu-t)py](-) = N-tert-butyl-N-2-pyridylnitroxide, indicate a 2.51 V stabilization of the 4+ oxidation state of Ce compared to [(Bu4N)-Bu-n](2)[Ce(NO3)(6)] in acetonitrile and a 2.95 V stabilization compared to the standard potential for the ion under aqueous conditions. Density functional theory calculations suggest that this preference for the higher oxidation state is a result of the tetrakis(nitroxide) ligand framework at the Ce cation, which allows for effective electron donation into, and partial covalent overlap with, vacant 4f orbitals with delta symmetry. The results speak to the behavior of CeO2 and related solid solutions in oxygen uptake and transport applications, in particular an inherent local character of bonding that stabilizes the 4+ oxidation state. The results indicate a cerium(IV) complex that has been stabilized to an unprecedented degree through tuning of its ligand-field environment.

  5. Surface and bulk 4f-photoemission spectra of CeIn3 and CeSn3

    International Nuclear Information System (INIS)

    Resonant photoemission spectroscopy was performed on CeIn3 and CeSn3 at the 4d-4f and 3d-4f core thresholds. Using the different surface sensitivity between the two photon energies, surface and bulk 4f-photoemission spectra were derived for both compounds. With the noncrossing approximation of the Anderson impurity model, the 4d-4f resonant spectra together with the surface and bulk spectra were self-consistently analyzed to obtain the microscopic parameters such as the 4f-electron energy and the hybridization strength with conduction electrons. The result shows a substantial difference in these parameters between the surface and the bulk, indicating that it is important to take into account the surface effect in analyzing photoemission spectra of Ce compounds. It is also found that the 4f surface core-level shift is different between CeIn3 and CeSn3. copyright 1997 The American Physical Society

  6. Transport properties of pure and doped CeO2

    International Nuclear Information System (INIS)

    The oxides that crystallize in the fluorite structure are noted for their ability to accommodate a high degree of disorder on the oxygen sublattice. Cerium oxide is a semiconductor and ionically- conductor oxide with important electrical and chemical applications as a solid oxide fuel cell electrolyte, a catalyst for gas phase oxidation and reduction reactions, and as an oxygen buffer in the automotive 3-way catalyst. Polycrystalline samples of different grain size were prepared by uniaxial hot pressing and their sintering behavior was investigated, at various temperatures and pressures. The cerium dioxide has been prepared by this way and characterized by X-ray diffraction and transmission electron microscopy (SEM). Measurements of electronic conductivity have confirmed that electron transport in CeO2-x proceeds via a small polaron process. The electrical properties of CeO2-UO2 solid solutions are examined as a function of temperature (600 deg. C - 1400 deg. C), oxygen partial pressure (10 - 22 - 1 atm), and Ce/U ratio (CeO2- 1.65% UO2, CeO2- 5% UO2). The PO2 values were controlled by mixing Ar-O2 and CO2-H2 or Ar-H2, gases in appropriate proportions. Electrical conductivity data obtained for U-doped CeO2 solid solution were shown to be in good agreement with predictions and thereby enable derivation of a number of key parameters, including those controlling generation of oxygen Frenkel defects, doubly ionized vacancies and electrons by reduction, and electron mobilities. (authors)

  7. Sensitive redox speciation of neptunium by CE-ICP-MS

    Energy Technology Data Exchange (ETDEWEB)

    Stoebener, Nils; Amayri, Samer; Gehl, Aaron; Kaplan, Ugras; Malecha, Kurtis; Reich, Tobias [Johannes Gutenberg-Universitaet Mainz, Institute of Nuclear Chemistry, Mainz (Germany)

    2012-11-15

    Capillary electrophoresis (CE) was used to separate the neptunium oxidation states Np(IV) and Np(V), which are the only oxidation states of Np that are stable under environmental conditions. The CE setup was coupled to an inductively coupled plasma mass spectrometer (Agilent 7500ce) using a Mira Mist CE nebulizer and a Scott-type spray chamber. The combination of the separation capacity of CE with the detection sensitivity of inductively coupled plasma mass spectrometry (ICP-MS) allows identification and quantification of Np(IV) and Np(V) at the trace levels expected in the far field of a nuclear waste repository. Limits of detection of 1 x 10{sup -9} and 5 x 10{sup -10} mol L{sup -1} for Np(IV) and Np(V), respectively, were achieved, with a linear range from 10{sup -9} to 10{sup -6} mol L{sup -1}. The method was applied to study the redox speciation of the Np remaining in solution after interaction of 5 x 10{sup -7} mol L{sup -1} Np(V) with Opalinus Clay. Under mildly oxidizing conditions, a Np sorption of 31% was found, with all the Np remaining in solution being Np(V). A second sorption experiment performed in the presence of Fe{sup 2+} led to complete sorption of the Np onto the clay. After desorption with HClO{sub 4}, a mixture of Np(IV) and Np(V) was found in solution by CE-ICP-MS, indicating that some of the sorbed Np had been reduced to Np(IV) by Fe{sup 2+}. (orig.)

  8. The solid solutions (Ce1-xLax)RuSn

    International Nuclear Information System (INIS)

    X-Ray-pure samples of the solid solutions (Ce1-xLax)RuSn were obtained up to x = 0.5. Powder diffraction data show the CeRuSn-type superstructure up to x ∼ 0.3 and the CeCoAl-type subcell for higher lanthanum contents. The structure of a single crystal with x = 0.5 was refined on the basis of single-crystal X-ray diffractometer data: CeCoAl type, C2/m, a = 1160.8(2), b = 477.6(1), c = 511.6(1) pm, β = 102.97(2) , wR = 0.0510, 444 F2 values, 20 variables. Magnetic investigations were performed for all samples up to a lanthanum content of x = 0.4. No cooperative phenomena could be observed, and all samples show Curie-Weiss behavior above a certain temperature. The cerium valence is about 3.32(2) for all samples of the solid solution. Hence, La3+ has to replace Ce3+ as well as Ce4+ in a particular quantity. The electrical resistivity measurements confirm the suppression of the magnetic ordering and the structural transition upon replacement of cerium by lanthanum. 119Sn Moessbauer spectra of samples with x = 0.2 and 0.5 are indicative of single tin sites with isomer shifts of δ = 1.86(1) mm s-1 for x = 0.2 and δ = 1.88(1) mm s-1 for x = 0.5. Both signals are subject to significant quadrupole splitting, a consequence of the low site symmetry. Results of XANES measurements are perfectly in line with the cerium valences determined by susceptibility measurements and yield a constant value of 3.16(1) for all investigated compounds. (orig.)

  9. Fabrication and characterization of spark plasma sintered Ce:LuAG ceramic for scintillation application

    Science.gov (United States)

    Kumar, S. Arun; Senthilselvan, J.

    2016-05-01

    Rare earth Cerium doped Lutetium Aluminum Garnet (Ce:LuAG) ceramics are widely used as phosphor material in medical imaging and high-energy physics. Due to its technological importance, an attempt has been made to fabricate Ce:LuAG ceramics by using spark plasma sintering (SPS) technique. XRD patterns of SPS sintered Ce:LuAG ceramics reveals a mixed LuAG and CeO2 (antisite defect) phases. The microstructures of SPS sintered Ce:LuAG ceramics shows limited densification, inappropriate compaction of particles and existence of residual pores, voids between the grain boundaries affects the transparency of Ce:LuAG ceramics. Relative density and hardness of post sintered Ce:LuAG ceramic is also determined. The effect of Ce3+ doping concentration and sintering temperature on optical luminescence behavior of Ce:LuAG ceramic is presented.

  10. Eletroforese capilar acoplada à espectrometria de massas (CE-MS: vinte anos de desenvolvimento Capillary electrophoresis coupled to mass spectrometry (CE-MS: twenty years of development

    Directory of Open Access Journals (Sweden)

    Nilson Antonio Assunção

    2008-01-01

    Full Text Available CE-MS has been increasingly used for analysis of a vast array of compounds. This article reviews the different electrophoretic modes, interfaces and mass analyzers that are commonly used in the CE-MS coupling, as well as the technique advantages and performance characteristics. A large compilation of CE-MS applications is also presented. Therefore, this review is both a guide for beginners and a collection of key references for people who are familiar to the technique. Furthermore, this is the first CE-MS review published in a Brazilian journal and marks the installation of the first two commercial CE-MS units in Sao Paulo State.

  11. Atomic transition probabilities of Ce I from Fourier transform spectra

    International Nuclear Information System (INIS)

    Atomic transition probabilities for 2874 lines of the first spectrum of cerium (Ce I) are reported. These data are from new branching fraction measurements on Fourier transform spectra normalized with previously reported radiative lifetimes from time-resolved laser-induced-fluorescence measurements (Den Hartog et al 2009 J. Phys. B: At. Mol. Opt. Phys. 42 085006). The wavelength range of the data set is from 360 to 1500 nm. Comparisons are made to previous investigations which are less extensive. Accurate Ce i transition probabilities are needed for lighting research and development on metal halide high-intensity discharge lamps.

  12. Atomic transition probabilities of Ce I from Fourier transform spectra

    Energy Technology Data Exchange (ETDEWEB)

    Lawler, J E; Wood, M P; Den Hartog, E A [Department of Physics, University of Wisconsin, 1150 University Ave., Madison, WI 53706 (United States); Chisholm, J [Department of Physics, Boston College, 140 Commonwealth Ave., Chestnut Hill, MA 02467 (United States); Nitz, D E [Department of Physics, St. Olaf College, 1520 St. Olaf Ave., Northfield, MN 55057 (United States); Sobeck, J, E-mail: jelawler@wisc.ed, E-mail: chishojd@bc.ed, E-mail: nitz@stolaf.ed, E-mail: mpwood@wisc.ed, E-mail: jsobeck@uchicago.ed, E-mail: eadenhar@wisc.ed [Department of Astronomy and Astrophysics, University of Chicago, 5640 Ellis Ave., Chicago, IL 60637 (United States)

    2010-04-28

    Atomic transition probabilities for 2874 lines of the first spectrum of cerium (Ce I) are reported. These data are from new branching fraction measurements on Fourier transform spectra normalized with previously reported radiative lifetimes from time-resolved laser-induced-fluorescence measurements (Den Hartog et al 2009 J. Phys. B: At. Mol. Opt. Phys. 42 085006). The wavelength range of the data set is from 360 to 1500 nm. Comparisons are made to previous investigations which are less extensive. Accurate Ce i transition probabilities are needed for lighting research and development on metal halide high-intensity discharge lamps.

  13. 57Fe NMR study of nitrided Ce2 Fe17

    International Nuclear Information System (INIS)

    The 57 Fe NMR of Ce2 Fe17 Nx (x=0-1.5) was measured in the ordered magnetic state at 4.2 K. For x = 0, resonances coming from all Fe sites have been identified in the 30 - 45 MHz range. With nitrogenation, new lines appear in the range 37 - 54 MHz. Every nitrogenated sample shows three sets of lines, arising from regions where Ce atoms have 0, 2, and 3 nitrogen atoms as near neighbors. (author). 5 refs., 1 fig

  14. Certification of Confluence Proofs using CeTA

    OpenAIRE

    Nagele, Julian; Thiemann, René

    2015-01-01

    CeTA was originally developed as a tool for certifying termination proofs which have to be provided as certificates in the CPF-format. Its soundness is proven as part of IsaFoR, the Isabelle Formalization of Rewriting. By now, CeTA can also be used for certifying confluence and non-confluence proofs. In this system description, we give a short overview on what kind of proofs are supported, and what information has to be given in the certificates. As we will see, only a small amount of informa...

  15. Pd/CeO2/SiC Chemical Sensors

    Science.gov (United States)

    Lu, Weijie; Collins, W. Eugene

    2005-01-01

    The incorporation of nanostructured interfacial layers of CeO2 has been proposed to enhance the performances of Pd/SiC Schottky diodes used to sense hydrogen and hydrocarbons at high temperatures. If successful, this development could prove beneficial in numerous applications in which there are requirements to sense hydrogen and hydrocarbons at high temperatures: examples include monitoring of exhaust gases from engines and detecting fires. Sensitivity and thermal stability are major considerations affecting the development of high-temperature chemical sensors. In the case of a metal/SiC Schottky diode for a number of metals, the SiC becomes more chemically active in the presence of the thin metal film on the SiC surface at high temperature. This increase in chemical reactivity causes changes in chemical composition and structure of the metal/SiC interface. The practical effect of the changes is to alter the electronic and other properties of the device in such a manner as to degrade its performance as a chemical sensor. To delay or prevent these changes, it is necessary to limit operation to a temperature sensor structures. The present proposal to incorporate interfacial CeO2 films is based partly on the observation that nanostructured materials in general have potentially useful electrical properties, including an ability to enhance the transfer of electrons. In particular, nanostructured CeO2, that is CeO2 with nanosized grains, has shown promise for incorporation into hightemperature electronic devices. Nanostructured CeO2 films can be formed on SiC and have been shown to exhibit high thermal stability on SiC, characterized by the ability to withstand temperatures somewhat greater than 700 C for limited times. The exchanges of oxygen between CeO2 and SiC prevent the formation of carbon and other chemical species that are unfavorable for operation of a SiC-based Schottky diode as a chemical sensor. Consequently, it is anticipated that in a Pd/CeO2/SiC Schottky

  16. Response of CeRh2Si2 to pressure

    International Nuclear Information System (INIS)

    Under atmospheric pressure, CeRh2Si2 orders antiferromagnetically at TN = 35 K, with magnetic entropy S = R ell n2 associated with the ordered groundstate. Application of modest pressure (∼9 kbar) to CeRh2Si2 suppresses TN to near zero Kelvin, increases its Sommerfeld coefficient of specific heat by nearly a factor of 3.5 and induces some form of superconductivity below 400 mK that is depressed by a magnetic field at a rate of -80 mK/kG

  17. Cesariana em animais de companhia: opções cirúrgicas e fatores de risco

    OpenAIRE

    Santos, Ana Cláudia Campos dos

    2016-01-01

    Dissertação de Mestrado Integrado em Medicina Veterinária O estudo retrospetivo incluiu quarenta e duas cadelas e quinze gatas sujeitas a cesariana por distócia (grupo CD e GD, respetivamente) e treze cadelas sujeitas a cesariana eletiva (grupo CE). Todos os casos foram recolhidos no Hospital Referência Veterinária Montenegro, durante o período de Março de 2008 até Junho de 2014. A cesariana pode ser indicada durante a gestação tardia em cadelas e gatas para resolução de casos de distóc...

  18. The <em>Opuntia streptacanthaem> <em>OpsHSP18 em>Gene Confers Salt and Osmotic Stress Tolerance in <em>Arabidopsis thalianaem>

    Directory of Open Access Journals (Sweden)

    Juan Francisco Jiménez-Bremont

    2012-08-01

    Full Text Available Abiotic stress limits seed germination, plant growth, flowering and fruit quality, causing economic decrease. Small Heat Shock Proteins (sHSPs are chaperons with roles in stress tolerance. Herein, we report the functional characterization of a cytosolic class CI sHSP (OpsHSP18 from <em>Opuntia streptacantha em>during seed germination in <em>Arabidopsis thalianaem> transgenic lines subjected to different stress and hormone treatments. The over-expression of the <em>OpsHSP18em> gene in <em>A. thalianaem> increased the seed germination rate under salt (NaCl and osmotic (glucose and mannitol stress, and in ABA treatments, compared with WT. On the other hand, the over-expression of the <em>OpsHSP18em> gene enhanced tolerance to salt (150 mM NaCl and osmotic (274 mM mannitol stress in <em>Arabidopsis> seedlings treated during 14 and 21 days, respectively. These plants showed increased survival rates (52.00 and 73.33%, respectively with respect to the WT (18.75 and 53.75%, respectively. Thus, our results show that <em>OpsHSP18em> gene might have an important role in abiotic stress tolerance, in particular in seed germination and survival rate of Arabidopsis plants under unfavorable conditions.

  19. Microstructure and Composition of a Ce-pyrochlore: A Chemical Analog for Pu-pyrochlore

    Science.gov (United States)

    Xu, Huifang; Wang, Yifeng; Garvie, Laurence A. J.; Putnam, Robert L.; Navrotsky, Alexandra

    2003-07-01

    Ce-pyrochlore (CaCeTi2O7), is a chemical analogue for CaPuTi2O7, which is a proposed ceramic waste form for deposition of excess weapon-usable Pu in geological repositories. Ce-pyrochlore was synthesized by firing and annealing a mixture of Ce(NO3)4, TiO2, and Ca(OH)2 with a stoichiometry of CaCeTi2O7 at 1,300°C for 50 hours. The annealed product contains Ce-pyrochlore, Ce-bearing perovskite, CeO2 (cerianite), and minor CaO. Electron energy-loss spectroscopy (EELS) was used to determine the valence of Ce in the synthesized materials using the shape of the Ce M4,5 edge. Cerium in the perovskite is dominated by Ce3+. The Ce4+/ΣCe in the pyrochlore is 0.8, giving (Ca0.87Ce0.203+Ce0.864+Ti0.05)Ti2O7. High-resolution TEM images show that the boundary between pyrochlore and perovskite is semicoherently bonded. The orientational relationship between the neighboring pyrochlore and perovskite is not random. There are no glassy phases observed at the grain boundaries between pyrochlore and perovskite, and between CeO2 and pyrochlore. It is postulated, based on the presence of trivalent Ce in the Ce-pyrochlore, that the neutron poisons such as Gd can be incorporated into the CaPuTi2O7 phase.

  20. Comparação dos estímulos clique e CE-chirp® no registro do Potencial Evocado Auditivo de Tronco Encefálico Comparison of click and CE-chirp® stimuli on Brainstem Auditory Evoked Potential recording

    Directory of Open Access Journals (Sweden)

    Gabriela Ribeiro Ivo Rodrigues

    2012-12-01

    Full Text Available OBJETIVO: Comparar as latências e as amplitudes da onda V no registro do Potencial Evocado Auditivo de Tronco Encefálico (PEATE com os estímulos clique e CE-chirp® e a presença ou ausência das ondas I, III e V em fortes intensidades. MÉTODOS: Estudo transversal com 12 adultos com limiares audiométricos PURPOSE: To compare the latencies and amplitudes of wave V on the Brainstem Auditory Evoked Potential (BAEP recording obtained with click and CE-chirp® stimuli and the presence or absence of waves I, III and V in high intensities. METHODS: Cross-sectional study with 12 adults with audiometric thresholds <15 dBHL (24 ears and mean age of 27 years. The parameters used for the recording with both stimuli in intensities of 80, 60, 40, 20 dBnHL were alternate polarity and repetition rate of 27.1 Hz. RESULTS: The CE-chirp® latencies for wave V were longer than click latencies at low intensity levels (20 and 40 dBnHL. At high intensity levels (60 and 80 dBnHL, the opposite occurred. Larger wave V amplitudes were observed with CE-chirp® in all intensity levels, except at 80 dBnHL. CONCLUSION: The CE-chirp® showed shorter latencies than those observed with clicks at high intensity levels and larger amplitudes at all intensity levels, except at 80 dBnHL. The waves I and III tended to disappear with CE-chirp® stimulation.

  1. Improved sulfur-resistant ability on CO oxidation of Pd/Ce0.75Zr0.25O2 over Pd/CeO2-TiO2 and Pd/CeO2

    Institute of Scientific and Technical Information of China (English)

    沈美庆; 林放; 魏光曦; 王建强; 朱少春

    2015-01-01

    The influence of sulfation on Pd/Ce0.75Zr0.25O2, Pd/CeO2-TiO2 and Pd/CeO2 was investigated. Physical structure and chemical properties of different catalysts were characterized by N2 adsorption, X-ray diffraction (XRD), CO chemisorption, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR) and X-ray fluorescence (XRF). After 10 h SO2 sulfation, it was found that the decrement on CO oxidation catalytic activity was limited on Pd/Ce0.75Zr0.25O2 compared to Pd/CeO2-TiO2 and Pd/CeO2. It demonstrated that Pd/Ce0.75Zr0.25O2 was more sulfur resistant compared to the other two catalysts. Af-ter sulfur exposure, catalyst texture was not much influenced as shown by N2 adsorption and XRD, and surface Pd atoms were poi-soned indicated by CO chemisorption results. Pd/Ce0.75Zr0.25O2 and Pd/CeO2-TiO2 exhibited less sulfur accumulation compared to Pd/CeO2 in the sulfation process. Furthermore, XPS results clarified that surface sulfur amount, especially surface sulfates amount on the sulfated catalysts was more crucial for the deactivation in sulfur containing environment.

  2. Doping effects on protonic conduction in SrCeO3- and BaCeO3 - based perovskites

    International Nuclear Information System (INIS)

    One studied the electric conductivity of SrCe1-xMxO3 and BaCe1-xMxO3 (M - rare-earth elements) proton conductors with the perovskite structure depending on the doping level. Occurrence of maximums and minimums of the proton conductivity was explained on the basis of the typical conductivity was explained on the basis of the typical structure variations of the lattice under doping. One studied the anomalies of BaCe1-xErxO3 ceramics properties within two-phase range on the basis of the concepts about percolation clusters. It is shown, that mobility percolation types in proton-conducting thin films and ceramics should differ essentially

  3. TDPAC study of 140Ce local susceptibility in the Kondo insulator system CeNi1-xCoxSn

    International Nuclear Information System (INIS)

    We have measured the local magnetic susceptibility (χloc) of 140Ce in the alloy system CeNi1-xCoxSn for x=0,0.3 and 0.38 in the range 28-300 K using TDPAC method. The results show strongly reduced χloc values in all the alloys. Using the Coqblin-Schrieffer model we obtain the Kondo temperatures TK to be 90, 112 and 170 K for x=0.0,0.38 and 0.30, respectively. In addition, for x=0.38, the data show an abrupt drop in the χloc value at 48 K indicating a first-order valence transition for Ce ions. (orig.)

  4. Optimization of the Time Response of LaBr3(Ce) Detectors, and Its Dependence on Ce Concentration

    Science.gov (United States)

    Vedia, V.; Mach, H.; Fraile, L. M.; Lalkovski, S.; Udías, J. M.

    Fast inorganic scintillators that exhibit good spectroscopy performance, like LaBr3(Ce), are the crystals of choice for many applications; they play a crucial role in the Ultra Fast Timing technique by virtue of their good energy resolution and fast response [1]. This method, which is very sensitive to the LaBr3(Ce) time resolution, allows measurements of nuclear level lifetimes down to few ps range. There are indications that the nominal Ce concentration does strongly influence on the timing properties as well as it varies the photon yield and the energy resolution [2]. In this work we have searched for the best settings in order to optimize the time resolution of three cylindrical LaBr3(Ce) detectors equipped with crystals identical in volume and shape but with different Ce dopant concentration. The time resolution of every detector depends on the proper selection of the fast photomultiplier tube and the set up parameters that can be further optimized by fine-tuning of the Constant Fraction Discrimination (CFD) and the PMT bias voltage. Very good time resolution can be obtained with the ORTEC 935 CFD for very short time-delays. Timing properties of the three crystals were studied by delayed coincidence measurements against a reference BaF2 detector, whose time response is well known. The LaBr3(Ce) detector and the reference unit were placed in a close geometry with the radioactive source in between. We report timing results measured at the 60Co and 22Na energies.

  5. Synthesis and Luminescence Properties of (La,Ce,Tb)BO_3 Phosphors%(La,Ce,Tb)BO_3的合成及光谱性质

    Institute of Scientific and Technical Information of China (English)

    王林生; 文小强; 周健; 赖华生; 王玉香; 黄可龙

    2009-01-01

    采用高温固相法合成了(La,Ce,Tb)BO_3绿色发光粉,并对该发光粉进行了XRD和SEM分析.结果表明:(La,Ce,Tb)BO_3的晶体结构和LaBO_3相同,Ce~(3+)、Tb~(3+)的掺入并没有改变晶体的结构,发光粉颗粒大小均匀,形貌规则,粒度在5 μm左右.研究了(La,Ce,Tb)BO_3的光谱性质,在(La,Ce,Tb)BO_3的发射和激发光谱中除了有Tb~(3+)的特征发射和激发峰外,还有Ce~(3+)的特征发射和激发峰.比较了(La,Ce)BO_3发射光谱和(La,Tb)BO_3的激发光谱,两者存在重叠,这为Ce~(3+)→Tb~(3+)的能量传递提供了条件.将(La,Ce,Tb)BO_3的发射光谱与商品粉(La,Ce,Tb)PO_4进行比较,两者的发射主峰都在541 nm处, (La,Ce,Tb)BO_3在489 nm处的峰位稍有红移,通过计算表明,(La,Ce,Tb)BO_3的发光亮度达到商品粉(La,Ce,Tb)PO_4的94.7%.因此,(La,Ce,Tb)BO_3是一种很有应用前景的绿色发光粉.

  6. Channeling Studies of CeO₂ and Ce₁-xZrxO₂ Films on Yttria-Stabilized ZrO₂(111)

    Energy Technology Data Exchange (ETDEWEB)

    Shutthanandan, V; Thevuthasan, Suntharampillai; Kim, Y J; Peden, Charles HF

    2001-07-01

    Rutherford backscattering spectrometry and channeling techniques have been used to investigate the crystalline quality and interfacial properties of epitaxially grown CeO₂ and Ce₀.₇Zr₀.₃O₂ films on yttria-stabilized ZrO₂(111) substrates. Both films appear to have high crystalline quality with minimum yeild of Ce in the CeO₂ and Ce₀.₇Zr₀.₃O₂ films determined to be 4.7% and 12.1% respectively. Visibility of more Ce atoms to the ion beam at the interface compared to the bulk of the film indicates that both films show significant disorder at the interface. The normalized angular yield curves obtained from Ce and Zr indicate that the Ce atomic rows in the CeO₂ film are parallel to the Zr atomic rows in the substrates. Both films appear to have high crystalline quality with minimum yeild of Ce in the CeO₂ and Ce₀.₇Zr₀.₃O₂ films determined to be 4.7% and 12.1% respectively. Visibility of more Ce atoms to the ion beam at the interface compared to the bulk of the film indicates that both films show significant disorder at the interface. The normalized angular yield curves obtained from Ce and Zr indicate that the Ce atomic rows in the CeO₂ film are parallel to the Zr atomic rows in the substrates. Approximately 88% of the Zr atoms substitutionally occupy the Ce cation lattice sites in the Ce₀.₇Zr₀.₃O₂ film.

  7. Effect of Ce concentration on luminescence properties of Gd3Ga3Al2O12:Ce nanocrystals

    Science.gov (United States)

    Singh, K. V.; Singh, J. P.; Shinde, S.; Singh, A. K.; Tyagi, M.

    2016-05-01

    Gd3Ga3Al2O12 (GGAG) polycrystalline nano-powders doped with different Ce concentrations were prepared by a co-precipitation method followed by heat treatment at 1000°C for 24 h in air and Ar ambient. Structural and morphological studies show that the synthesized powder is pure phase having nanometer (30-50 nm) particle size. Luminescence studies carried out using UV and X-ray excitations revealed a decrease in the luminescence intensity for a Ce concentration greater than 0.5 mol% due to the concentration quenching.

  8. Technologie leptání křemíku

    OpenAIRE

    Krátký, Stanislav

    2012-01-01

    Tato práce se zabývá technologií mokrého a suchého leptání křemíku. Zkoumá se použití vodného roztoku hydroxidu draselného. V suchých technikách se práce zaměřuje na plazmatické leptání křemíku směsí CF4+O2. U obou leptacích procesů jsou stanoveny důležité parametry leptání, jako je rychlost leptání křemíku, maskovacího materiálu, selektivita leptání, drsnost povrchu a podleptání masky. Řeší se zde i další pomocné a přípravné práce v technologii leptání. Konkrétně jde o vytváření masky v rezi...

  9. Information System through ANIS at CeSAM

    Science.gov (United States)

    Moreau, C.; Agneray, F.; Gimenez, S.

    2015-09-01

    ANIS (AstroNomical Information System) is a web generic tool developed at CeSAM to facilitate and standardize the implementation of astronomical data of various kinds through private and/or public dedicated Information Systems. The architecture of ANIS is composed of a database server which contains the project data, a web user interface template which provides high level services (search, extract and display imaging and spectroscopic data using a combination of criteria, an object list, a sql query module or a cone search interfaces), a framework composed of several packages, and a metadata database managed by a web administration entity. The process to implement a new ANIS instance at CeSAM is easy and fast : the scientific project has to submit data or a data secure access, the CeSAM team installs the new instance (web interface template and the metadata database), and the project administrator can configure the instance with the web ANIS-administration entity. Currently, the CeSAM offers through ANIS a web access to VO compliant Information Systems for different projects (HeDaM, HST-COSMOS, CFHTLS-ZPhots, ExoDAT,...).

  10. Low Cost CE-NMR with Microcoils for Chemical Detection

    Energy Technology Data Exchange (ETDEWEB)

    Adams, K L; Klunder, G; Demas, V; Malba, V; Bernhardt, A; Evan, L; Harvey, C; Maxwell, R; Herberg, J

    2008-07-25

    Understanding speciation in solids and solutions is important for environmental and toxicological purposes. Capillary electrophoresis (CE) is a simple rapid separation technique that can be used to identify species in solution. CE is particularly is well suited for rapid separations of metal containing samples. Direct on-capillary measurement of metal compound speciation can be obtained with nuclear magnetic resonance (NMR). The development of a low-cost microcoil CE-NMR system for in situ characterization of samples of interest is discussed. High precision laser lithography is used to produce copper sputtered microcoils that have comparable resistivity and quality factors to that of hand wound microcoils. A portable NMR system coupled with a CE system has the potential to identify chemical species in aqueous solutions. In addition, transient isotachophoresis can separate and pre-concentrate samples of interest to obtain separate chemical peaks for speciation by online NMR analysis. We are developing separation assays to determine the speciation of chemical complexes in solutions with minimal perturbation to the original sample equilibrium. On-line NMR measurements will be made downstream of the UV detector.

  11. Low Cost CE-NMR with Microcoils for Chemical Detection

    Energy Technology Data Exchange (ETDEWEB)

    Adams, K; Klunder, G; Demas, V; Malba, V; Bernhardt, A; Evan, L; Harvey, C; Maxwell, R; Herberg, J L

    2009-01-08

    Understanding speciation in solids and solutions is important for environmental and toxicological purposes. Capillary electrophoresis (CE) is a simple rapid separation technique that can be used to identify species in solution. CE is particularly is well suited for rapid separations of metal containing samples. Direct on-capillary measurement of metal compound speciation can be obtained with nuclear magnetic resonance (NMR). The development of a low-cost microcoil CE-NMR system for in situ characterization of samples of interest is discussed. High precision laser lithography is used to produce copper sputtered microcoils that have comparable resistivity and quality factors to that of hand wound microcoils. A portable NMR system coupled with a CE system has the potential to identify chemical species in aqueous solutions. In addition, transient isotachophoresis can separate and pre-concentrate samples of interest to obtain separate chemical peaks for speciation by online NMR analysis. We are developing separation assays to determine the speciation of chemical complexes in solutions with minimal perturbation to the original sample equilibrium. On-line NMR measurements will be made downstream of the UV detector.

  12. A Sesame Equation of State for Dense Ce

    Energy Technology Data Exchange (ETDEWEB)

    Greeff, Carl William [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Crockett, Scott [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-03-15

    We generated a new Sesame equation of state table for Ce. It is a single effective phase table for the high density phases α, α ', ϵ and liquid. Also, the EOS is meant to be used with a ramp to represent the initial low density γ phase.

  13. Improved performance of QCD code on ALiCE

    CERN Document Server

    Sroczynski, Z

    2003-01-01

    We present results for the performance of QCD code on ALiCE, the Alpha-Linux Cluster Engine at Wuppertal. We describe the techniques employed to optimise the code, including the metaprogramming of assembler kernels, the effects of data layout and an investigation into the overheads incurred by the communication.

  14. Investigation of positive parity degenerate dipole bands in 133Ce

    International Nuclear Information System (INIS)

    A pair of dipole bands B2 and B3 have been identified with same parity in 133Ce. To study the decay properties of these bands and measure their electromagnetic transition strengths, an experiment was carried out to collect high statistics and high fold γ-coincidence data

  15. 32 CFR Appendix B to Part 247 - CE Publications

    Science.gov (United States)

    2010-07-01

    ... statement of work with appropriate contractual terms and conditions, using 48 CFR chapter I and II as guides... Printing. While CE contracts are not subject to the FAR (48 CFR chapter I) or the DFARS (48 CFR chapter II... sources include the OASD(PA), AFIS, the Military Departments and their subordinate levels of command,...

  16. Magnetotransport in CeCu6-xAux

    International Nuclear Information System (INIS)

    We report on a comparative study of the low-temperature magnetoresistance ρxx(B) and Hall resistance ρxy(B) of CeCu6-xAux for 0=xx(B), and of the anomalous Hall effect and bandstructure effects of the heavy-quasiparticle bands affecting ρxy(B)

  17. O- centers in LuAG:Ce,Mg ceramics

    Czech Academy of Sciences Publication Activity Database

    Hu, C.; Liu, S.; Fasoli, M.; Vedda, A.; Nikl, Martin; Feng, X. Q.; Pan, Y.B.

    2015-01-01

    Roč. 9, č. 4 (2015), s. 245-249. ISSN 1862-6254 R&D Projects: GA ČR GAP204/12/0805 Institutional support: RVO:68378271 Keywords : scintillator * hole center * EPR * LuAG * Ce 3+ Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.142, year: 2014

  18. Nuclear data treatment for SAM-CE Monte Carlo calculations

    International Nuclear Information System (INIS)

    The treatment of nuclear data by the SAM-CE Monte Carlo code system is presented. The retrieval of neutron, gamma production, and photon data from the ENDF/B fils is described. Integral cross sections as well as differential data are utilized in the Monte Carlo calculations, and the processing procedures for the requisite data are summarized

  19. Estimation of bulk transfer coefficient for latent heat flux (Ce)

    Digital Repository Service at National Institute of Oceanography (India)

    Sadhuram, Y.

    The bulk transfer coefficient for latent heat flux (Ce) has been estimated over the Arabian Sea from the moisture budget during the pre-monsoon season of 1988. The computations have been made over two regions (A: 0-8 degrees N: 60-68 degrees E: B: 0...

  20. Electrochemical formation process and phase control of Mg-Li-Ce alloys in molten chlorides

    Institute of Scientific and Technical Information of China (English)

    ZHANG Meng; HAN Wei; ZHANG Milin; ZHU Fengyan; XUE Yun; ZHANG Zhijian

    2013-01-01

    An electrochemical approach for the preparation of Mg-Li-Ce alloys by co-reduction of Mg,Li and Ce on a molybdenum electrode in KCl-LiCl-MgCl2-CeCl3 melts at 873 K was investigated.Cyclic voltammograms (CVs) and square wave voltammograms indicated that the underpotential deposition (UPD) of cerium on pre-deposited magnesium led to the formation of Mg-Ce alloys at electrode potentials around-1.87 V.The order of electrode reactions was as follows:discharge of Mg(Ⅱ) to Mg-metal,UPD of Ce on the surface of pre-deposited Mg with formation of Mg-Ce alloys,discharge of Ce(Ⅲ) to Ce-metal and after that the discharge of Li+ with the deposition of Mg-Li-Ce alloys,which was investigated by CVs,chronoamperometry,chronopotentiometry and open circuit chronopotentiometry.X-ray diffraction (XRD) illuminated that Mg-Li-Ce alloys with different phases were obtained via galvanostatic electrolysis by different current densities.The microstructures of Mg-Li-Ce alloys were characterized by optical microscopy (OM) and scanning electron microscopy (SEM),respectively.The analysis of energy dispersive spectrometry (EDS) showed that Ce existed at grain boundaries to restrain the grain growth.The compositions and the average grain sizes of Mg-Li-Ce alloys could be obtained controllably corresponding with the phase structures of the XRD patterns.

  1. Expression of Selected <em>Ginkgo em>>biloba em>Heat Shock Protein Genes After Cold Treatment Could Be Induced by Other Abiotic Stress

    Directory of Open Access Journals (Sweden)

    Feng Xu

    2012-05-01

    Full Text Available Heat shock proteins (HSPs play various stress-protective roles in plants. In this study, three <em>HSP> genes were isolated from a suppression subtractive hybridization (SSH cDNA library of <em>Ginkgo bilobaem> leaves treated with cold stress. Based on the molecular weight, the three genes were designated <em>GbHSP16.8em>, <em>GbHSP17em> and <em>GbHSP70em>. The full length of the three genes were predicted to encode three polypeptide chains containing 149 amino acids (Aa, 152 Aa, and 657 Aa, and their corresponding molecular weights were predicted as follows: 16.67 kDa, 17.39 kDa, and 71.81 kDa respectively. The three genes exhibited distinctive expression patterns in different organs or development stages. <em>GbHSP16.8em> and <em>GbHSP70em> showed high expression levels in leaves and a low level in gynoecia, <em>GbHSP17em> showed a higher transcription in stamens and lower level in fruit. This result indicates that <em>GbHSP16.8em> and <em>GbHSP70 em>may play important roles in <em>Ginkgo> leaf development and photosynthesis, and <em>GbHSP17em> may play a positive role in pollen maturation. All three <em>GbHSPs> were up-regulated under cold stress, whereas extreme heat stress only caused up-regulation of <em>GbHSP70em>, UV-B treatment resulted in up-regulation of <em>GbHSP16.8em> and <em>GbHSP17em>, wounding treatment resulted in up-regulation of <em>GbHSP16.8em> and <em>GbHSP70em>, and abscisic acid (ABA treatment caused up-regulation of <em>GbHSP70em> primarily.

  2. New CeMgCo4 and Ce2MgCo9 compounds: Hydrogenation properties and crystal structure of hydrides

    Science.gov (United States)

    Denys, R. V.; Riabov, A. B.; Černý, R.; Koval'chuk, I. V.; Zavaliy, I. Yu.

    2012-03-01

    Two new ternary intermetallic compounds, CeMgCo4 (C15b pseudo-Laves phase, MgCu4Sn type) and Ce2MgCo9 (substitution derivative of PuNi3 type) were synthesized by mechanical alloying method. The structural and hydrogenation properties of these compounds were studied by X-ray diffraction and Pressure-Composition-Temperature measurements. Both compounds absorb hydrogen at room temperature and pressures below 10 MPa forming hydrides with maximum compositions CeMgCo4H6 and Ce2MgCo9H12. Single plateau behavior was observed in P-C isotherm during hydrogen absorption/desorption by Ce2MgCo9 alloy. The CeMgCo4-H2 system is characterized by the presence of two absorption/desorption plateaus corresponding to formation of β-CeMgCo4H4 and γ-CeMgCo4H6 hydride phases. The structure of β-hydride CeMgCo4H(D)4 was determined from X-ray and neutron powder diffraction data. In this structure initial cubic symmetry of CeMgCo4 is preserved and hydrogen atoms fill only one type of interstitial sites, triangular MgCo2 faces. These positions are occupied by 70% and form octahedron around Mg atom with Mg-D bond distances 1.84 Å.

  3. Magnetic properties of Ce3+ in PbCeA (A= Te, Se, S

    Directory of Open Access Journals (Sweden)

    Golacki Z.

    2013-01-01

    Full Text Available The magnetic susceptibility of Pb1-xCexA (A = S, Se and Te crystals with 0.006 ≤  x ≤ 0.036  were studied in the temperature range from 20 mK up to room temperature. X-band (~9.5 GHz Electron Paramagnetic Resonance (EPR showed small shifts in the effective Landé factors that were attributed to crystal-field admixture. The EPR measurements were correlated with the magnetic susceptibility data and resulted in estimating the crystal-field splitting Δ = E(Γ8 - E(Γ7 of the lowest 2F5/2 manifold for Ce3+ ions in PbA (A = S, Se and Te of about 340 K, 440 K and 540 K for Pb1-xCexTe, Pb1-xCexSe, and Pb1-xCexS, respectively. The values for the crystal-field splitting deduced from the magnetic data were found to be in agreement with the calculated ones based on the point charge model. Moreover, the deHaas van-Alphen magnetic oscillations in the susceptibility measurements of Pb1-xCexTe (x~ 0.05 and 0.07 were observed at ultra-low temperature (20 mK; The oscillations were investigated and the values of the oscillatory period for Pb1-xCexTe (x = 0.0048 and 0.007 are reported.

  4. Características agronômicas do amendoinzeiro sob irrigação com águas salinas em solo com biofertilizantes = Agronomics Characteristicsof Peanuts under irrigation with saline water on soil with biofertilizers.

    OpenAIRE

    Geocleber Gomes de Sousa; Benito Moreira de Azevedo; André Henrique Pinheiro Albuquerque; José Bruno Rego de Mesquita; Thales Vinicius de Araújo Viana

    2012-01-01

    Objetivou-se com esse trabalho avaliar o efeito da salinidade da água de irrigação nas características agronômicas do amendoinzeiro (Arachis hypogaea L.) cultivado em solo sem e com biofertilizantes. O experimento foi conduzido em estufa telada na Estação Agrometereológica, Campus do Pici, Fortaleza, CE. A semeadura foi feita em vasos utilizando-se, como substrato, um Argissolo Vermelho-Amarelo, com uma planta por vaso. O experimento obedeceu a um delineamento inteiramente casualizado, em esq...

  5. Composição química e classes de lipídios em peixe de água doce Curimatã comum, Prochilodus cearensis

    OpenAIRE

    Everardo L. MAIA; OLIVEIRA Cláudia C. S. de; André P. SANTIAGO; CUNHA Francisca E. A.; HOLANDA Francisco C. A. F.; Janaína A. SOUSA

    1999-01-01

    O presente trabalho teve como objetivo obter dados quantitativos sobre as classes de lipídios presentes no filé de curimatã, Prochilodus cearensis. Os lipídios totais (LT) foram fracionados em classes de lipídios neutros (LN), gliceroglicolipídios (GL) e glicerofosfolipídios (PL) através de cromatografia em coluna aberta de sílica gel 60 (70-230 mesh). As análises foram realizadas em quatro lotes de amostras contendo cada uma três exemplares, adquiridos em feiras livres de Fortaleza-CE, nos m...

  6. Optically and thermally stimulated luminescence of KMgF3:Ce3+ and NaMgF3:Ce3+

    International Nuclear Information System (INIS)

    The potentialities of optically stimulated luminescence (OSL) for personal dosimetry of ionising radiation have stimulated the search for new synthetic materials with good dosimetric properties. The sensitivity of two new OSL materials KMgF3 and NaMgF3 doped with Ce3+ ions has been evaluated and found to be of the same order of magnitude as that of Al2O3:C. Several other characteristics have also been investigated. Promising results for KMgF3:Ce are the high sensitivity and the low fading. However, this material suffers from a high self-dose due to the presence of 40K. NaMgF3:Ce is sensitive as well but shows strong fading. Interesting information on the mechanism has been obtained by correlating the signals of OSL and TL. Furthermore, the different bleachabilities under blue LED illumination of the strongly overlapping glow peaks allowed the extraction of one single peak for KMgF3:Ce3+. The results demonstrate new possibilities offered by the combination of TL and OSL. (author)

  7. Evaluation of production samples of the scintillators LaBr3:Ce and LaCl3:Ce

    International Nuclear Information System (INIS)

    We report on the evaluation of the performance of two recently developed scintillator materials, LaCl3:Ce and LaBr3:Ce, at the task of gamma ray spectroscopy. Their performance is compared to a standard scintillator used for gamma ray spectroscopy--a 25 mm diameter 25 mm tall cylinder of NaI:Tl. We measure the pulse height, energy resolution, and full-energy efficiency of production LaBr3:Ce and LaCl3:Ce scintillation crystals of different sizes and geometries for a variety of gamma-ray energies. Using production rather than specially selected crystals will establish whether immediate large-scale use is feasible. The crystal is excited by gamma rays from one of six isotopic sources (125I, 241Am, 57Co, 22Na, 137Cs, and 60Co) placed 15 cm away from the scintillator. Our measurements show that both LaCl3 and LaBr3 outperform NaI:Tl in almost all cases. They outperform NaI:Tl at all energies for the photopeak fraction and counting rate measurements, and for energy resolution at higher energies (above 200 keV for LaCl3 and 75 keV for LaBr3). The performance of production crystals is excellent and these scintillators should be considered for immediate use in systems where stopping power and energy resolution are crucial

  8. Preparation and Characterization of CeO2/YSZ/CeO2 Buffer Layers for YBCO Coated Conductors

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    CeO2 seed layer was deposited on rolling-assisted biaxially textured metal substrates by direct-current (DC) magnetron reactive sputtering. The effect of deposition temperature on epitaxial orientation of CeO2 thin films was examined. High quality CeO2 layers were achieved at deposition temperature from 750℃ to 850℃.Subsequently yttria-stabilized zirconia (YSZ) and CeO2 films were deposited to complete the buffer layer structure via the same process. The best samples exhibited a highly biaxial texture, as indicated by FWHM (full width half maximum) values in the range of 4°-5°, and 2°-4° for in-plane and out-of-plane orientations,respectively. Secondary ion mass spectrometer analysis confirmed the effective prevention of buffer layer against Ni and W metal interdiffusion. Atomic force microscope observations revealed a smooth, dense and crack-free surface morphology, which provided themselves as the good buffer structure to the YBa2Cu3O7-δ(YBCO) coated conductors.

  9. Osteoartrites em equinos

    OpenAIRE

    Rocha, Francisco José Martins

    2008-01-01

    Dissertação de Mestrado Integrado em Medicina Veterinária A Osteoartrite (OA) é a principal causa de claudicação no cavalo de desporto e lazer, sendo uma afecção que tem grandes repercussões económicas. Este trabalho descreve algumas das características importantes da estrutura articular, bem como da sua fisiologia. Define a OA e todas as estruturas envolvidas no seu processo. Os mecanismos fisiopatológicos põem em evidência os factores de risco em causa e que determinam tod...

  10. A creche em Portugal

    OpenAIRE

    Serrano, Leonor; Pinto, Jorge

    2015-01-01

    Na evolução das creches em Portugal verifica-se uma alternância entre conceções assistencialista de integração educacional. Procura-se refletir sobre a tensão existente entre estas duas perspetivas relativamente ao atendimento em creche em Portugal. A creche foi considerada como local de guarda por impedimento dos pais, no entanto no decurso dos tempos assistimos a tentativas de a assumir como um serviço de prestação de cuidados e de educação promovendo um desenvolvimento mais holístico e res...

  11. Homeopatia em Pediatria

    OpenAIRE

    Pinto, Ana Isabel Alves

    2013-01-01

    Numa sociedade em constante processo de formação e de informação, não conhecer determinada terapia não pode ser a resposta de um profissional de farmácia ao seu utente. A divulgação massiva de tratamentos naturalistas, alternativos e baseados em saberes ancestrais, frequentemente entram em conflito com as prescrições médicas e aconselhamentos farmacêuticos. Com as medicinas alternativas a ganhar terreno paulatinamente, como se observa com a utilização da acupunctura e de fitote...

  12. Controle de Sitophilus zeamais Mots., 1855 (Coleoptera: Curculionidae com inseticidas empregados em frutíferas temperadas

    Directory of Open Access Journals (Sweden)

    Faria João Luiz

    2005-01-01

    Full Text Available O gorgulho do milho Sitophilus zeamais Mots. tem sido relatado com freqüência atacando frutíferas temperadas em condições de campo, com destaque para o pessegueiro em Pelotas, RS, macieira em Fraiburgo, SC e videira na Serra Gaúcha, RS. Este trabalho avaliou, em laboratório, o efeito dos inseticidas deltametrina (Decis 25 CE, 40mL 100L-1, dimetoato (Dimetoato 400 CE, 150mL 100L-1, triclorfon (Dipterex 500 SNAqC, 300mL 100L-1, fosmet (Imidan 500 PM, 200g 100L-1, fention (Lebaycid 500 CE, 100mL 100L-1, clorpirifós (Lorsban 480 BR, 150mL 100L-1, malation (Malation 1000, 200mL 100L-1, carbaril (Sevin 480 SC, 360mL 100L-1, fenitrotion (Sumithion 500 CE, 150mL 100L-1 e metidation (Supracid 400 CE, 100mL 100L-1 atualmente empregados no controle de pragas em frutíferas temperadas e os novos inseticidas tiametoxam (Actara 250 WG, 15 e 30g 100L-1, benzoato de emamectina (Proclaim 5 SG, 10 e 20g 100L-1, imidacloprid (Provado 200 SC, 30 e 60mL 100L-1, spinosad (Tracer 480 CE, 10 e 20mL 100L-1 e etofenprox (Trebon 100 SC, 100 e 150mL 100L-1. No primeiro experimento, frutos de maçã foram mergulhados na calda inseticida por 10 segundos e oferecidos a adultos de S. zeamais sp (contato residual e, no segundo, os produtos foram aplicados diretamente sobre os insetos (contato direto em torre de pulverização. Os inseticidas triclorfon (150g 100L-1, fention (50g 100L-1, clorpirifós (72g 100L-1, malation (200g 100L-1, metidation (40g 100L-1 e tiametoxam (3,75 e 7,5g 100L-1 foram eficientes no controle do gorgulho do milho, via contato residual, enquanto fention (50g 100L-1, clorpirifós (72g 100L-1, malation (200g 100L-1, fenitrotion (75g 100L-1 e metidation (40g 100L-1 foram eficientes via contato direto.

  13. Electronic structure of CeO studied by a four-component relativistic configuration interaction method.

    Science.gov (United States)

    Moriyama, Hiroko; Tatewaki, Hiroshi; Yamamoto, Shigeyoshi

    2013-06-14

    We studied the ground and excited states of CeO using the restricted active space CI method in the energy range below 25,000 cm(-1). Energy levels are computed to within errors of 2700 cm(-1). Electron correlation effects arising from the ionic core composed of Ce5s, 5p, 4f(*), 5d(*), and O2s, 2p spinors play crucial role to CeO spectra, as well as correlation effects of electrons distributed in the valence Ce 4f, 5d, 6s, and 6p spinors. Here, 4f(*) and 5d(*) denote spinors expanded to describe electron polarization between Ce and O. A bonding mechanism is proposed for CeO. As the two separate atoms in their ground states, Ce(4f(1)5d(1)6s(2))(1)G4 and O(2s(2)2p(4))(3)P2, approach each other, a CeO(2+) core is formed by two-electron transfer from Ce5d, 6s to O2p. Inside this ellipsoidal ion, a valence bond between Ce5p and O2s and an ionic bond between O2p and Ce5p are formed with back-donation through Ce 4f(*) and 5d(*). PMID:23781798

  14. Effect of CeO2 Infiltration on Hybrid Direct Carbon Fuel Cell Performance

    DEFF Research Database (Denmark)

    Ippolito, Davide; Deleebeeck, Lisa; Kammer Hansen, Kent

    2014-01-01

    The effect of CeO2 infiltration into the anode or CeO2 mixed with the carbon-fuel on the performance of a Hybrid Direct Carbon Fuel Cell (HDCFC) was studied through the use of polarization curves and electrochemical impedance spectroscopy. The use CeO2 in both ways helped to increase the cell...

  15. CeRu2Si2: an example of heavy fermion metamagnetism

    International Nuclear Information System (INIS)

    The strong interplay between lattice, electronic and magnetic properties in CeRu2Si2 is emphasized. Special attention is given on the broadening of the metamagnetic-like transition. Comparison is made with similar phenomena in other heavy fermion cerium compounds: CeCu6, CeAl3. ((orig.))

  16. CeCu2Si2: More nearly magnetic than UBe13

    International Nuclear Information System (INIS)

    We have prepared and studied, via dc and ac susceptibility and specific heat, samples of Ce1-xMxCu2.2Si2, with M=Y, La, and Lu. All samples show an increase in the Wilson ratio, ∝χ/γ, with the low-temperature χ per Ce mole increasing from Lu to Y to La and Ce1-xLaxCu2.2Si2 actually having χ(1.8 K) per Ce mole larger than in pure CeCu2.2Si2 for x>0.5. The low-temperature specific heat of CeCu2.2Si2 is enhanced by dilution by La, when normalized per Ce mole, whereas dilution by Y and Lu strongly depresses the per-Ce-mole specific heat. These two contrasting effects may be linked to a volume effect, since Y and Lu contract the CeCu2.2Si2 lattice while La expands it. The fact that dilute Ce in the expanded host lattice Ce1-xLaxCu2.2Si2 has increased χ and γ at low temperatures argues for a nearness to magnetism (substantiated by recent work on Ce1-xThxCu2.2Si2) that contrasts with results for U1-xMxBe13

  17. Chemical Composition and <em>in Vitroem> Evaluation of the Antioxidant and Antimicrobial Activities of <em>Eucalyptus gillii em>Essential Oil and Extracts<em>>

    Directory of Open Access Journals (Sweden)

    François Couderc

    2012-08-01

    Full Text Available In this study, essential oil and various extracts (hexane, petroleum ether, acetone, ethanol, methanol and water of <em>Eucalyptus giliiem> were screened for their chemical composition, antimicrobial and antioxidant activities. The essential oil chemical composition was analyzed by gas chromatography-mass spectrometry (GC-MS and gas chromatography-flame ionization detection (GC-FID, respectively. Thirty four compounds were identified, corresponding to 99.5% of the total essential oil. Tannins [104.9–251.3 g catechin equivalent (CE/Kg dry mass], flavonoids [3.3–34.3 g quercetin equivalent (QE/Kg dry mass], phenolics [4.7–216.6 g gallic acid equivalent (GAE/Kg dry mass] and anthocyannins [1.2–45.3 mg cyanidin-3-glucoside equivalent (C3GE/Kg dry mass] of various extracts were investigated. Free radical scavenging capacity of all samples was determinedt. In the 1,1-diphenyl-2-picrylhydrazyl (DPPH assay, the IC50 of essential oil was 163.5 ± 10.7 mg/L and in the 2,2'-azinobis-3-ethylbenzothiazoline-6-sulphonate (ABTS assay, it was 94.7 ± 7.1 mg/L. Among the various extracts, the water extract showed the best result (IC50 = 11.4 ± 0.6 mg/L in the DPPH assay which was comparable to vitamin C (IC50 = 4.4 ± 0.2 mg/L. The antimicrobial activities were evaluated against different bacterial and fungal strains. Gram positive bacteria were found to be more sensitive to the essential oil and extracts than Gram negative ones. Anthocyanins seem to have a major effect on the growth of <em>Bacillus subtilisem> (R2 = 0.79. A significant antifungal activity was observed against the yeast and fungi. Correlations between chemical composition and antioxidant activities were studied and R2 values were about 0.96 for the effect of phenolics on the DPPH assay.

  18. Idosos residentes em uma instituição de longa permanência: adaptação à luz de Callista Roy

    OpenAIRE

    Maria Célia de Freitas; Maria Vilani Cavalcante Guedes; Francisca Tereza de Galiza; Jéssica de Menezes Nogueira; Marília Ribeiro Onofre

    2014-01-01

    Objetivou-se avaliar o processo de adaptação de idosos que buscam, voluntariamente, residir em Instituição de Longa Permanência para Idosos (ILPI), na cidade de Fortaleza-CE, com base no modelo teórico de Roy. Pesquisa descritiva, realizada em uma IPLI com treze idosos residentes. A coleta de dados foi por meio de entrevista, nos meses de outubro e dezembro de 2011. Os dados foram tratados pela análise de conteúdo temática. Emergiram as seguintes temáticas: Eu Físico, subdividido em sensação ...

  19. Glycosylation of Vanillin and 8-Nordihydrocapsaicin by Cultured <em>Eucalyptus perrinianaem> Cells

    Directory of Open Access Journals (Sweden)

    Naoji Kubota

    2012-05-01

    Full Text Available Glycosylation of vanilloids such as vanillin and 8-nordihydrocapsaicin by cultured plant cells of <em>Eucalyptus perrinianaem> was studied. Vanillin was converted into vanillin 4-<em>O>-b-D-glucopyranoside, vanillyl alcohol, and 4-<em>O>-b-D-glucopyranosylvanillyl alcohol by <em>E. perriniana em>cells. Incubation of cultured <em>E. perrinianaem> cells with 8-nor- dihydrocapsaicin gave 8-nordihydrocapsaicin 4-<em>O>-b-D-glucopyranoside and 8-nordihydro- capsaicin 4-<em>O>-b-D-gentiobioside.

  20. Study of the <em>in Vitroem> Antiplasmodial, Antileishmanial and Antitrypanosomal Activities of Medicinal Plants from Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Nawal M. Al-Musayeib

    2012-09-01

    Full Text Available The present study investigated the <em>in vitroem> antiprotozoal activity of sixteen selected medicinal plants. Plant materials were extracted with methanol and screened <em>in vitroem> against erythrocytic schizonts of <em>Plasmodium falciparumem>, intracellular amastigotes of <em>Leishmania infantum em>and <em>Trypanosoma cruzi em>and free trypomastigotes of<em> T. bruceiem>. Cytotoxic activity was determined against MRC-5 cells to assess selectivity<em>. em>The criterion for activity was an IC50 < 10 µg/mL (4. Antiplasmodial activity was found in the<em> em>extracts of<em> em>>Prosopis julifloraem> and <em>Punica granatumem>. Antileishmanial activity<em> em>against <em>L. infantumem> was demonstrated in <em>Caralluma sinaicaem> and <em>Periploca aphylla.em> Amastigotes of<em> T. cruzi em>were affected by the methanol extract of<em> em>>Albizia lebbeckem>> em>pericarp, <em>Caralluma sinaicaem>,> Periploca aphylla em>and <em>Prosopius julifloraem>. Activity against<em> T. brucei em>was obtained in<em> em>>Prosopis julifloraem>. Cytotoxicity (MRC-5 IC50 < 10 µg/mL and hence non-specific activities were observed for<em> em>>Conocarpus lancifoliusem>.>

  1. Molecular magnetism and crystal field effects in the Kondo system Ce{sub 3}Pd{sub 20}(Si,Ge){sub 6} with two Ce sublattices

    Energy Technology Data Exchange (ETDEWEB)

    Nikiforov, V.N. [M.V. Lomonosov Moscow State University, Moscow 119992 (Russian Federation); Koksharov, Yu.A. [M.V. Lomonosov Moscow State University, Moscow 119992 (Russian Federation); Kurnakov Institute of General and Inorganic Chemistry, Leninskii pr. 31, Moscow 119991 (Russian Federation); Gribanov, A.V. [M.V. Lomonosov Moscow State University, Moscow 119992 (Russian Federation); Baran, M. [Institute of Physics, Polish Academy of Science, Warsaw (Poland); Irkhin, V.Yu., E-mail: valentin.irkhin@imp.uran.ru [Institute of Metal Physics, Ekaterinburg 620990 (Russian Federation)

    2015-06-01

    The unusual electronic and magnetic properties of the systems Ce{sub 3}Pd{sub 20}T{sub 6} (T=Ge, Si) with two non-equivalent Ce positions are discussed. The logarithmic growth of resistance for both systems confirms the presence of the Kondo effect in the two respective temperature ranges. The two-scale behavior is explained by consecutive splitting of Ce ion levels in the crystal field. The effects of the frustration caused by the coexistence of the different Ce positions are treated, which may also significantly enhance the observed values of specific heat. A model of “molecular magnetism” with Ce2 cubes is developed. - Highlights: • We study unusual properties of the systems Ce{sub 3}Pd{sub 20}T{sub 6} with two Ce positions. • The logarithmic growth of resistance confirms presence of the Kondo effect. • The effects of the frustration owing to different Ce positions are discussed. • A model of “molecular magnetism” with Ce2 cubes is developed.

  2. Physical, biochemical and genetic characterization of enterocin CE5-1 produced by Enterococcus faecium CE5-1 isolated from Thai indigenous chicken intestinal tract

    Directory of Open Access Journals (Sweden)

    Kraiyot Saelim

    2015-06-01

    Full Text Available Enterocin CE5-1 produced by Enterococcus faecium CE5-1 isolated from the chicken gastrointestinal tract was active in the wide range of pH 2-10 and temperature 30-100°C and sensitive to proteolytic enzymes and -amylase. It remained active after storage at -20°C for 2 months. Moreover, enterocin CE5-1 showed antibacterial activity against lactobacilli, bacilli, listeria, staphylococci and enterococci, especially antibiotic-resistant enterococci. In vitro study of enterocin CE5-1 decreased the population of Ent. faecalis VanB from 6.03 to 4.03 log CFU/ml. The lethal mode of action of enterocin CE5-1 appeared to be pore and filament formation in the cell wall. PCR sequencing analysis revealed the presence of two open reading frames (ORFs, containing enterocin CE5-1 (entCE5-1 and enterocin immunity (entI gene. Therefore, enterocin CE5-1 from Ent. faecium CE5-1 could possibly be used as an antimicrobial agent to control foodborne pathogen, spoilage bacteria and antibiotic-resistant enterococci in foods, feeds and the environments.

  3. Morphology-dependent bactericidal activities of Ag/CeO2 catalysts against Escherichia coli.

    Science.gov (United States)

    Wang, Lian; He, Hong; Yu, Yunbo; Sun, Li; Liu, Sijin; Zhang, Changbin; He, Lian

    2014-06-01

    Silver-loaded CeO2 nanomaterials (Ag/CeO2) including Ag/CeO2 nanorods, nanocubes, nanoparticles were prepared with hydrothermal and impregnation methods. Catalytic inactivation of Escherichia coli with Ag/CeO2 catalysts through the formation of reactive oxygen species (ROS) was investigated. For comparison purposes, the bactericidal activities of CeO2 nanorods, nanocubes and nanoparticles were also studied. There was a 3-4 log order improvement in the inactivation of E. coli with Ag/CeO2 catalysts compared with CeO2 catalysts. Temperature-programmed reduction of H2 showed that Ag/CeO2 catalysts had higher catalytic oxidation ability than CeO2 catalysts, which was the reason for that Ag/CeO2 catalysts exhibited stronger bactericidal activities than CeO2 catalysts. Further, the bactericidal activities of CeO2 and Ag/CeO2 depend on their shapes. Results of 5,5-dimethyl-1-pyrroline-N-oxide spin-trapping measurements by electron spin resonance and addition of catalase as a scavenger indicated the formation of OH, O2(-), and H2O2, which caused the obvious bactericidal activity of catalysts. The stronger chemical bond between Ag and CeO2 nanorods led to lower Ag(+) elution concentrations. The toxicity of Ag(+) eluted from the catalysts did not play an important role during the bactericidal process. Experimental results also indicated that Ag/CeO2 induced the production of intracellular ROS and disruption of the cell wall and cell membrane. A possible production mechanism of ROS and bactericidal mechanism of catalytic oxidation were proposed. PMID:24662462

  4. Air, aqueous and thermal stabilities of Ce3+ ions in cerium oxide nanoparticle layers with substrates

    KAUST Repository

    Naganuma, Tamaki

    2014-01-01

    Abundant oxygen vacancies coexisting with Ce3+ ions in fluorite cerium oxide nanoparticles (CNPs) have the potential to enhance catalytic ability, but the ratio of unstable Ce3+ ions in CNPs is typically low. Our recent work, however, demonstrated that the abundant Ce3+ ions created in cerium oxide nanoparticle layers (CNPLs) by Ar ion irradiation were stable in air at room temperature. Ce valence states in CNPs correlate with the catalytic ability that involves redox reactions between Ce3+ and Ce4+ ions in given application environments (e.g. high temperature in carbon monoxide gas conversion and immersion conditions in biomedical applications). To better understand the mechanism by which Ce3+ ions achieve stability in CNPLs, we examined (i) extra-long air-stability, (ii) thermal stability up to 500 °C, and (iii) aqueous stability of Ce 3+ ions in water, buffer solution and cell culture medium. It is noteworthy that air-stability of Ce3+ ions in CNPLs persisted for more than 1 year. Thermal stability results showed that oxidation of Ce 3+ to Ce4+ occurred at 350 °C in air. Highly concentrated Ce3+ ions in ultra-thin CNPLs slowly oxidized in water within 1 day, but stability was improved in the cell culture medium. Ce 3+ stability of CNPLs immersed in the medium was associated with phosphorus adsorption on the Ce3+ sites. This study also illuminates the potential interaction mechanisms of stable Ce3+ ions in CNPLs. These findings could be utilized to understand catalytic mechanisms of CNPs with abundant oxygen vacancies in their application environments. © The Royal Society of Chemistry 2014.

  5. Purification, Characterization and Antioxidant Activities <em>in Vitroem>> em>and <em>in Vivoem> of the Polysaccharides from <em>Boletus edulisem> Bull

    Directory of Open Access Journals (Sweden)

    Yijun Fan

    2012-07-01

    Full Text Available A water-soluble polysaccharide (BEBP was extracted from <em>Boletus edulis em>Bull using hot water extraction followed by ethanol precipitation. The polysaccharide BEBP was further purified by chromatography on a DEAE-cellulose column, giving three major polysaccharide fractions termed BEBP-1, BEBP-2 and BEBP-3. In the next experiment, the average molecular weight (Mw, IR and monosaccharide compositional analysis of the three polysaccharide fractions were determined. The evaluation of antioxidant activities both <em>in vitroem> and <em>in vivo em>suggested that BEBP-3 had good potential antioxidant activity, and should be explored as a novel potential antioxidant.

  6. A specimen of <em>Sorex> cfr. <em>samniticus> in Barn Owl's pellets from Murge plateau (Apulia, Italy / Su di un <em>Sorex> cfr. <em>samniticus> (Insectivora, Soricidae rinvenuto in borre di <em>Tyto albaem> delle Murge (Puglia, Italia

    Directory of Open Access Journals (Sweden)

    Giovanni Ferrara

    1992-07-01

    Full Text Available Abstract In a lot of Barn Owl's pellets from the Murge plateau a specimen of <em>Sorex> sp. was detected. Thank to some morphological and morphometrical features, the cranial bones can be tentatively attributed to <em>Sorex samniticusem> Altobello, 1926. The genus <em>Sorex> was not yet included in the Apulia's fauna southwards of the Gargano district; the origin and significance of the above record is briefly discussed, the actual presence of a natural population of <em>Sorex> in the Murge being not yet proved. Riassunto Viene segnalato il rinvenimento di un esemplare di <em>Sorex> cfr. <em>samniticus> da borre di <em>Tyto albaem> delle Murge. Poiché il genere non era stato ancora segnalato nella Puglia a sud del Gargano, viene discusso il significato faunistico del reperto.

  7. 10 GHz 2ωce heavy ion source CAPRICE

    International Nuclear Information System (INIS)

    By using a new 0.8 T sextupole, the second step of metamorphosis of the ECR magnetic structure of the CAPRICE source is achieved. The 2ωce surface is now extended everywhere in the second stage except the extraction part. Thus, a strong flux of deconfined plasma is available at the extraction area and therefore high currents of high charge state ions are extracted. Optimum rf power is increased by a factor of 3 with respect to the single ωce profile and currents of high charge state ions are increased by a factor of 10. The optimum performance for all gases and all solid elements is shown. The third step of the metamorphosis is planned for next year to achieve and work with two complete ECR surfaces. Future developments are also expected. (orig./HSI)

  8. Anisotropic Thermoelectric Properties of CeRhAs with Superstructures

    International Nuclear Information System (INIS)

    We report thermoelectric, magnetic and structural properties of the so-called Kondo semiconductor CeRhAs. The resistivity ρ(T) along the three principal axes exhibits step-like anomalies at T1 = 370, T2 = 235 and T3 = 165 K, respectively, and increases by two orders of magnitude on cooling to 1.5 K. Below T1 an abrupt drop in the magnetic susceptibility along all the axes is associated with the cell doubling along the b - and c -axes, suggesting a charge-density-wave transition. Below T3 the increase in the thermopower is strongest along the a -axis with a maximum of 186 μV/K at 35 K. The thermoelectric figure of merit becomes largest along the c-axis with the maximum value of 1.0x10-3/K, being comparable with that of CePd3. (author)

  9. Boèce, Traité de la musique

    OpenAIRE

    Lejbowicz, Max

    2008-01-01

    Le destin du De institutione musica de Boèce est étrange. Si l’on excepte une allusion purement rhétorique de son rival Cassiodore, trois siècles séparent la rédaction du texte de son premier témoin, sans que les spécialistes se soient accordés sur l’origine de l’archétype (voir, dans le livre sous examen, les p. 12-13). Mais, à partir de cette résurgence, quel succès ! Entre le VIIIe et le XVe s., ce sont près de cent soixante-dix manuscrits qu’il faut compter, tandis que la Renaissance l’éd...

  10. Thermal Conductivity of Ce Doped Bi-2212 Superconductors

    Institute of Scientific and Technical Information of China (English)

    LI Bo; WU Bai-Mei; M.Ausloos

    2004-01-01

    The temperature dependence of the thermal conductivity in Bi2Sr2 Ca1-x Cex Cu2Oy x = 0.1, 0.2, 0.3, 0.4 is presented. With increasing Ce-doping level, the thermal conductivity peak under TC is suppressed then disappears,while another peak appears at low temperatures for the non-superconducting compounds. The numerical analysis shows that the thermal conductivity peak under TC can be well described by the normal electron relaxation-time contribution model, and the phonon-induced thermal conductivity peak could be well described within the Debye approximation of the phonon spectrum. The existence and variation of these two thermal conductivity peaks indicate the adjustability between the superconducting and insulating components in the samples with different Ce-doping levels.

  11. Dynamic correlations in the Kondo system CeAl2

    International Nuclear Information System (INIS)

    Complete text of publication follows. CeAl2 exhibits a very complex magnetic behaviour due to the interplay between the RKKY-interaction and the Kondo effect not fully investigated until now. Inelastic neutron scattering experiments have been performed on CeAl2 below the Neel temperature TN = 3.8 K in the zero field multi-domain-state and also in a single-domain-state generated by applying a magnetic field and have determined the magnetic excitation spectra along the [1-10]-direction. In both cases the magnetic excitations are found to be very broad in energy and they differ only slightly in the intensity distribution. In zero magnetic field the excitation spectra do not change much with temperature and the inelastic signal is still observed at temperatures up to about 4 times TN. (author)

  12. Identification and Quality Assessment of Chrysanthemum Buds by CE Fingerprinting

    Directory of Open Access Journals (Sweden)

    Xiaoping Xing

    2015-01-01

    Full Text Available A simple and efficient fingerprinting method for chrysanthemum buds was developed with the aim of establishing a quality control protocol based on biochemical makeup. Chrysanthemum bud samples were successively extracted by water and alcohol. The fingerprints of the chrysanthemum buds samples were obtained using capillary electrophoresis and electrochemical detection (CE-ED employing copper and carbon working electrodes to capture all of the chemical information. 10 batches of chrysanthemum buds were collected from different regions and various factories to establish the baseline fingerprint. The experimental data of 10 batches electropherogram buds by CE were analyzed by correlation coefficient and the included angle cosine methods. A standard chrysanthemum bud fingerprint including 24 common peaks was established, 12 from each electrode, which was successfully applied to identify and distinguish between chrysanthemum buds from 2 other chrysanthemum species. These results demonstrate that fingerprint analysis can be used as an important criterion for chrysanthemum buds quality control.

  13. CE separation approaches for combinations of anthracyclines and taxanes.

    Science.gov (United States)

    Shakalisava, Yuliya; Regan, Fiona

    2009-09-01

    For the first time the versatility of CE is demonstrated for the separation of different types of anticancer drugs - anthracyclines and taxanes simultaneously. The use of these drugs in combination therapy for cancer has sparked interest in the development of methods for potential application. The simultaneous analysis of anthracyclines and taxanes can significantly increase a sample throughput of a clinical laboratory. The study shows the potential of CE for such a challenge: anthracyclines and taxanes were separated by CZE, MEKC and MEEKC. The MEEKC method was successfully applied to these compounds for the first time and was characterised by very short separation time, high efficiencies of peaks and was proven to be generic for the separation of different combinations of anthracyclines and taxanes. This separation approach could be highly beneficial for clinical analysis if applied with a sensitive detection system. MEKC and high-speed MEEKC methods were proven to show good potential in their application to plasma samples. PMID:19681049

  14. TRX and UO2 criticality benchmarks with SAM-CE

    International Nuclear Information System (INIS)

    A set of thermal reactor benchmark calculations with SAM-CE which have been conducted at both MAGI and at BNL are described. Their purpose was both validation of the SAM-CE reactor eigenvalue capability developed by MAGI and a substantial contribution to the data testing of both ENDF/B-IV and ENDF/B-V libraries. This experience also resulted in increased calculational efficiency of the code and an example is given. The benchmark analysis included the TRX-1 infinite cell using both ENDF/B-IV and ENDF/B-V cross section sets and calculations using ENDF/B-IV of the TRX-1 full core and TRX-2 cell. BAPL-UO2-1 calculations were conducted for the cell using both ENDF/B-IV and ENDF/B-V and for the full core with ENDF/B-V

  15. The data distribution of the ESPaCE project

    Science.gov (United States)

    Thuillot, W.

    2015-10-01

    In the framework of the European Union project entitled ESPaCE (European Satellite Partnership for Computing Ephemerides, 2011-2015) we have carried out research by collecting unexploited space data and ground-based data for providing new dynamical orbit models and ephemeris of natural satellites and spacecraft orbits. Besides new digitization of old astrometric plate data, Radio Science, VLBI tracking, Laser Ranging methods are applied to these goals. Furthermore shape and gravity field data, reference systems are provided for several natural satellites. This project intends to put all this material online for free access by the scientific community. We will describe the data acquisition and distribution performed and in particular the setup of the ESPaCE-NSDB astrometric database.

  16. Catalisadores cerâmicos à base de CuO/CeO2 aplicados na reação de oxidação preferencial do CO Ceramic catalysts based on CuO/CeO2 used in the reaction of preferential oxidation of CO

    Directory of Open Access Journals (Sweden)

    L. S. Neiva

    2012-09-01

    Full Text Available A oxidação preferencial do CO (PROX é o método mais adequado para a purificação de fluxos gasosos ricos em H2. Catalisadores de CuO/CeO2 têm sido desenvolvidos e apresentados como uma alternativa bastante promissora para a reação de oxidação preferencial do CO-PROX-CO. O objetivo deste trabalho é sintetizar catalisadores cerâmicos a base de CuO/CeO2 por meio do método de síntese Pechini, caracterizar e analisar as suas estruturas e avaliar a performance catalítica destes materiais aplicados na reação de PROX-CO. Foram desenvolvidas duas amostras de catalisadores cerâmicos à base CuO/CeO2, uma contendo 0,1 mol de CuO e outra contendo 0,5 mol do mesmo óxido. De acordo com os resultados, ambas as amostras sintetizadas mostraram-se aptas a serem utilizadas em processos de conversão de CO para CO2. No entanto, a amostra que continha 0,1 mol de CuO mostrou-se mais ativa cataliticamente do que a amostra que continha 0,5 mol da mesma espécie ativa catalítica.The preferential oxidation of CO (PROX is the most suitable method for the purification of gas streams rich in H2. CuO/CeO2 catalysts have been developed and presented as a promising alternative for the preferential oxidation reaction of CO - CO-PROX. The aim this work is to synthesize CuO/CeO2 ceramic catalysts by means of the synthesis Pechini's method, characterization and analysis the structures and evaluation of the performance of these materials used in catalytic reaction of CO-PROX. Two samples ceramic catalysts based on CuO/CeO2 were synthesized, the first containing 0.1 mol of CuO and the second containing 0.5 mol of CuO. According to the results, both synthesized samples were ready to be used in a process of converting CO to CO2. However, the sample containing 0.1 mol of CuO was more active than the catalyst sample containing 0.5 mol of the same active species.

  17. Ni-CeO2 Cermets Synthesis by Solid State Sintering of Ni/CeO2 Multilayer

    Directory of Open Access Journals (Sweden)

    Aleksandras ILJINAS

    2013-12-01

    Full Text Available Nickel and gadolinium doped cerium oxide (GDC cermet is intensively investigated for an application as an anode material for solid oxide fuel cells based on various electrolytes. The purpose of the present investigation is to analyze morphology, microstructure, and optical properties of deposited and annealed for one hour in the temperatures from 500 ºC to 900 ºC Ni/CeO2 multilayer thin films deposited by sputtering. The crystallographic structure of thin films was investigated by X-ray diffraction. The morphology of the film cross-section was investigated with scanning electron microscope. The elemental analysis of samples was investigated by energy-dispersive X-ray spectroscopy. The fitting of the optical reflectance data was made using Abeles matrix method that is used for the design of interference coatings. The film cross-section of the post-annealed samples consisted of four layers. The first CeO2 layer (on Si had the same fine columnar structure with no features of Ni intermixing. The part of Ni (middle-layer after annealing was converted to NiO with grain size exceeding 100 nm. The CeO2 layer deposited on Ni was divided into two layers. Lower layer had small grains not exceeding 25 nm and consisting of NiO and CeO2 mixture. Upper layer consisted of CeO2 columns with approximate thickness of 50 nm. Ni sample annealed at 600 ºC was fully oxidized. The NiO thickness and refraction index were almost steady after annealing in various temperatures. The approximation of experimental reflectance data was successful only for the samples with one transparent homogeneous layer. The reflectance of the Ni/CeO2 samples annealed at intermediate temperatures could not be fitted using one-layer or three-layer model. That may show that a simplified model could not be implemented. The real system has complicated distribution of refraction index. DOI: http://dx.doi.org/10.5755/j01.ms.19.4.3073

  18. Estudos sobre a Esquistosomose em Pernambuco, Brasil

    Directory of Open Access Journals (Sweden)

    Aggeu Magalhães

    1940-01-01

    Full Text Available Os autores referem os resultados dos estudos sobre esquistosomose realisados, em Pernambuco, de Novembro de 1938 a Dezembro de 1939. Não se extendem em discussão, nem comentarios, tampouco, relacionam suas verificações com o que já foi relatado sobre o assunto em trabalhos nacionais e estrangeiros, pelo fato de que, não se trata de um resultado definitivo e sim de atividades que irão proseguir. Os estudos sistematicos em torno da endemia esquistosomica foram executados em duas localidades diversas pela população e pela situação geografica e ecologica. Pontezinha é uma povoação de 1200 habitantes localizada proximo a um conjunto de charcos e lagõas de agua dôce onde pululam caramujos do tipo olivaceus de Spix, e apresenta uma taxa de infestação de 21,4% para individuos do sexo masculino, e de 14,7% para os do sexo feminino. A distribuição por grupos de idade mostra que a incidencia cresce até o grupo de 16 a 20 anos de idade, quando atinge a percentagem de 37,8%, para decrescer em seguida. Em Vitoria a incidencia foi maior nos indivíduos do sexo feminino, atingindo a taxa de 41,4%, dando o sexo masculino a taxa de 36,9%. Por idade a percentagem maxima é atingida pelo grupo de 11 a 15 anos. Vitoria é uma cidade de 1500 habitantes, construida á margem do rio Tapacurá, onde se encontram numerosos caramujos do tipo centimetralis Lutz. A divergencia de incidencia corre por conta dos habitos da população e pela utilização que ela faz do rio, sendo maior em Vitoria porque a proximidade do rio facilita o uso de suas aguas para banho e serviços domesticos, condicionando este ultimo fato, a maior infestação das mulheres. O estudo da frequencia da infestação dos caramujos por cercarias de diversos trematodios, permite suspeitar uma relação inversa entre a taxa de infestação e o diametro maximo atingido pelos caramujos, parecendo este fato confirmar os trabalhos de Vianna Martins sobre a identidade dos hospedeiros

  19. Commensurate-commensurate magnetic phase transitions in CeSb

    DEFF Research Database (Denmark)

    Lebech, Bente; Broholm, C.; Clausen, K.; Vogt, O.

    The q=2/3 to q=4/7 commensurate-commensurate phase transition in CeSb has been studied by neutron diffraction. On cooling the commensurate wave vector q changes abruptly from 2/3 to a higher-order commensurate value (≈14/23) at T1

  20. Experimental investigation of the structure of 124Ce

    International Nuclear Information System (INIS)

    Gamma-ray transitions have been observed for the first time in 124Ce using the Daresbury Recoil Separator. The excitation energy of the first excited state, 142keV, implies a deformation epsilon2 approx. = 0.31. This value confirms the trend to higher deformation for the more neutron-deficient cerium isotopes, but it is larger than that predicted by recent calculations. (author)

  1. Burstein Moss effect in nanocrystalline CaS : Ce

    Indian Academy of Sciences (India)

    Geeta Sharma; Puja Chawla; S P Lochab; Nafa Singh

    2011-07-01

    The nanocrystalline CaS : Ce nanophosphors are synthesized by wet chemical co-precipitation method. The particles possess an average size of 10 nm as calculated using Debye–Scherrer formula. The particle size and the crystalline nature of the formed nanoparticles are confirmed by TEM micrograph. The optical studies are carried out using UV–Vis absorption spectroscopy. The absorption edge is found to show blue shift with increasing cerium concentration. The shift may be attributed to Burstein Moss effect.

  2. Itinerant magnetism in CeRh3B2

    DEFF Research Database (Denmark)

    Eriksson, Olle; Johansson, Börje; Brooks, M. S. S.;

    1989-01-01

    Spin-polarized energy-band calculations, including spin-orbit coupling in the band Hamiltonian, have been performed on CeRh3B2. Good agreement is obtained between theory and experiment concerning the magnetic moment. It is also found that the magnetic moment varies strongly with volume and from t...... this a qualitative explanation for the anomalously high Curie temperature of the compound is proposed. Furthermore, the spin density is found to be highly nonspherical....

  3. A new 144Ce/144Pr radioisotope generator system

    International Nuclear Information System (INIS)

    A miniaturized generator system was developed containing manganese dioxide-coated alumina on which 144Ce is deposited and from which 144Pr is eluted with an aqueous solution of 1% KIO3 in 1 N nitric acid. More than 60% of the 144Pr was recovered with a 99.9% radionuclide purity even after 2000 ml eluant and 1000 1 or air had been passed through the column. (author)

  4. Structure of ∼130 nuclei in La–Ce region

    Indian Academy of Sciences (India)

    Tumpa Bhattacharjee

    2010-07-01

    The variety of shapes and structures, observed in light rare earth $A ∼ 130$ nuclei, have been discussed in view of different angular momentum coupling schemes and their interplay that comes into effect at high spin. The = 79 and 80 isotopes in La–Ce region, produced via fusion evaporation reaction, have been studied using the Indian National Gamma Array (INGA) consisting of 18 clover HPGe detectors. Two nearly degenerate = 1 bands have been observed at high spin of 137Ce and a triaxial deformation of = ± 30°$ has been assigned to the bands, from the total Routhian surface (TRS) calculations. The high-spin candidates of the yrast band of 138Ce show signature splitting both in energy and (1)/(2) values. The bandcrossing due to the alignment of a pair of ℎ11/2 proton particles has been conjectured at ħ ω ∼ 0.3 MeV, from the single-particle Routhians obtained from TRS calculations. Lifetime measurements by Doppler shift attenuation method (DSAM) has been carried out and from the estimated reduced transition probability (1), the = 1 band in 138Ce has been characterized as a magnetic rotation (MR) band. The rise in the values of (1), for the higher spin candidates of the band, has been conjectured as the reopening of a different shear at the top of the Band B1. The characteristic of the MR bands in ∼ 130 region has been discussed in the light of a phenomenological calculation and compared to the MR bands in other mass regions.

  5. Parallel CE/SE Computations via Domain Decomposition

    Science.gov (United States)

    Himansu, Ananda; Jorgenson, Philip C. E.; Wang, Xiao-Yen; Chang, Sin-Chung

    2000-01-01

    This paper describes the parallelization strategy and achieved parallel efficiency of an explicit time-marching algorithm for solving conservation laws. The Space-Time Conservation Element and Solution Element (CE/SE) algorithm for solving the 2D and 3D Euler equations is parallelized with the aid of domain decomposition. The parallel efficiency of the resultant algorithm on a Silicon Graphics Origin 2000 parallel computer is checked.

  6. Gd interactions in (Ce,Gd)Al3

    International Nuclear Information System (INIS)

    The susceptibility of Ce1√/sub x/Gd/sub x/Al3 for 0.08≤x≤0.9 has an anomaly which resembles that associated with a spin-glass transition. For x greater than the percolation threshold concentration for antiferromagnetism at x≅0.5, the size of the susceptibility anomaly decreases two orders of magnitude and a resistivity anomaly appears

  7. Proposal for product development model focused on ce certification methodology

    Directory of Open Access Journals (Sweden)

    Nathalia Marcia Goulart Pinheiro

    2015-09-01

    Full Text Available This paper presents a critical analysis comparing 21 product development models in order to identify whether these structures meet the demands Product Certification of the European Community (CE. Furthermore, it presents a product development model, comprising the steps in the models analyzed, including improvements in activities for referred product certification. The proposed improvements are justified by the growing quest for the internationalization of products and processes within companies.

  8. Violet/blue photoluminescence from CeO2 thin film

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    CeO2 thin film was fabricated by dual ion beam epitaxial technique. The violet/blue PL at room temperature and lower temperature was observed from the CeO2 thin film. After the analysis of crystal structure and valence in the compound was carried out by the XRD and XPS technique, it was inferred that the origin of CeO2 PL was due to the electrons transition from Ce4f band to O2p band and the defect level to O2p band. And these defects levels were located in the range of 1 eV around Ce4f band.

  9. Investigation into kinetics of redox interaction in the system Ce(4) β-diketonate-additional ligand

    International Nuclear Information System (INIS)

    The rate of reduction of β-diketonate complexes of Ce(4) to Ce(3) β-diketonates in benzene solution in the presence and in the absence of additional ligands is studied using spectrophotometry. The rate of reduction of Ce(4) β-diketonates increases in the series Ce(TTFA)44444 (TTFA - thenoyltrifluoroacetone, DPM- --dipivaloylmethane, DBM - dibenzoylemethane, BA benzoylacetone, AA - acetylaceton). The studied phosphorus-containing additional ligands as to their effect on the rate of Ce (4) reduction can be arranged in the following order: trioctylphosphine oxide>triphenylphosphine oxide>tributyl phosphate

  10. Electron spectroscopic investigation of metal-insulator transition in Ce1-SrTiO3

    Indian Academy of Sciences (India)

    U Manju; S R Krishnakumar; Sugata Ray; S Raj; M Onoda; C Carbone; D D Sarma

    2003-10-01

    We have carried out detailed electron spectroscopic investigation of Ce1-SrTiO3 exhibiting insulator-metal transition with . Core level X-ray photoelectron spectra of Ce 3 as well as resonant photoemission spectra obtained at the Ce 4 → 4 resonant absorption threshold establish Ce as being in the trivalent state throughout the series. Using the `off-resonance’ condition for Ce 4 states, we obtain the Ti 3 dominated spectral features close to , exhibiting clear signatures of coherent and incoherent peaks. We discuss the implications of our findings in relation to the metal-insulator transition observed in this series of compounds.

  11. Carrier-free 139Ce obtaining and separation from lanthanum target

    International Nuclear Information System (INIS)

    The isotope 139Ce is widely used as a component of calibration multisources. In our laboratory preparation of high purity carrier-free 139Ce was worked out. The thick target yield of 139Ce produced by bombardment of 139La with 13 MeV deuterons was found to be 4.3 μCi/μAh. The product 139Ce was separated from macroquantities of lanthanum by extraction with diethyl ether (DEE) in the system DEE-HNO3. The optimum conditions of 139Ce isolation were determined. (author). 4 figs

  12. Magnetic Phase Transitions of CeSb. I

    DEFF Research Database (Denmark)

    Fischer, Pernille Hertz; Lebech, Bente; Meier, G.; Rainford, B. D.; Vogt, O.

    1978-01-01

    The magnetic ordering of the anomalous antiferromagnet CeSb, which has a NaCl crystal structure, was determined in zero applied magnetic field by means of neutron diffraction investigations of single crystals and powder. Below the Neel temperature TN of (16.1+or-0.1)K, there exist six partially...... disordered magnetic phases of antiphase domain type ((100) superstructures) with (100) orientation of the magnetic moments. At 4.4K, the ordered magnetic moment equals (2.10+or-0.04) mu B, which corresponds to the free-ion value of 2.14 mu mB for Ce3+. The temperature dependence of the ordered moment shows a...... first-order phase transition at TN. At approximately TN/2 there is a first-order phase transition to a FCC type IA low-temperature configuration. The unusual magnetic properties of CeSb, which result from anisotropic exchange and crystalline electric field effects, resemble those of certain actinide Na...

  13. Zur Analyse der Fügung ce fripon de valet

    Directory of Open Access Journals (Sweden)

    Moritz Regula

    2016-02-01

    Full Text Available Alle bisherigen Deutungen des Syntagmas ce tripon de valet sorgfältig überprüfend, gelangt S t. Lyer in einer historisch und psychologisch unter­ bauten Sonderstudie: Les appositions romanes du type li tel d'anemis, ce tripon de valet (ZRPh, LVIII, S. 348-359 zu dem überzeugenden Ergebnis, dass die: erwähnten Fügungen nicht als Fortsetzung der lat. Wendungen scelus viri, jlagitium hominis, monstrum mulieris, sondern als Neuschöpfung der Affektsyntax zu betrachten sind. Auch darin wird man dem Verfasser beipflichten müssen, dass die Fügung ce tripon de valet nicht mit dem in mehrfacher Hinsicht abweichenden Typ la ville de Paris auf einen Plan gestellt werden kann. Wenn ich trotz der in den Hauptpunkten bestehenden Übereinstimmung dasselbe Problem nochmals aufrolle, geschieht es, urn nach Beseitigung einer Unvollkommenheit in der Strukturanalyse eine eindeutige Diagnose der Satzgliendschaft beider Elemente zu gewinnen.

  14. Radon gamma-ray spectrometry with YAP:Ce scintillator

    CERN Document Server

    Plastino, W; De Notaristefani, F

    2002-01-01

    The detection properties of a YAP:Ce scintillator (YAlO sub 3 :Ce crystal) optically coupled to a Hamamatsu H5784 photomultiplier with standard bialkali photocathode have been analyzed. In particular, the application to radon and radon-daughters gamma-ray spectrometry was investigated. The crystal response has been studied under severe extreme conditions to simulate environments of geophysical interest, particularly those found in geothermal and volcanic areas. Tests in water up to a temperature of 100 deg.C and in acids solutions such as HCl (37%), H sub 2 SO sub 4 (48%) and HNO sub 3 (65%) have been performed. The measurements with standard radon sources provided by the National Institute for Metrology of Ionizing Radiations (ENEA) have emphasized the non-hygroscopic properties of the scintillator and a small dependence of the light yield on temperature and HNO sub 3. The data collected in this first step of our research have pointed out that the YAP:Ce scintillator can allow high response stability for rad...

  15. Level structure studies in 140La and 140Ce

    International Nuclear Information System (INIS)

    Energy and relative intensity measurements with precision have been done in 140Li and 140Ce using 8 c.c. Ge(Li) detector. In addition, gamma-gamma directional correlation measurements were carried out for 537-(14)-30, 305-(133)-30 and 305-162 keV cascades in 140Ia and 329-487, 487-1596 and 329-487, 487-1596 and 329-(487)-1596 keV cascades in 140Ce. From the data, spin assignments 0- and 1- have been made to the 581 and 468 keV levels in 140La. Multipole admixtures in 30,305,162,329, and 487 keV gamma-rays have been found to be M1+(2.5 +-.5)%E2, M1+(94+-1)%E2, M+(1+-.5)%E2, E2+(2+-1)%M3 and M1+0.25%E2 respectively. A comparison of experimental transition probabilities with Weisskopf estimates describes low lying states of 140La as states in which f7sub(/)2 neutron is coupled to unpaired proton and these of 140Ce, as single particle states with some core contribution. (author)

  16. Optical properties of CeO2 thin films

    Indian Academy of Sciences (India)

    S Debnath; M R Islam; M S R Khan

    2007-08-01

    Cerium oxide (CeO2) thin films have been prepared by electron beam evaporation technique onto glass substrate at a pressure of about 6 × 10-6 Torr. The thickness of CeO2 films ranges from 140–180 nm. The optical properties of cerium oxide films are studied in the wavelength range of 200–850 nm. The film is highly transparent in the visible region. It is also observed that the film has low reflectance in the ultra-violet region. The optical band gap of the film is determined and is found to decrease with the increase of film thickness. The values of absorption coefficient, extinction coefficient, refractive index, dielectric constant, phase angle and loss angle have been calculated from the optical measurements. The X-ray diffraction of the film showed that the film is crystalline in nature. The crystallite size of CeO2 films have been evaluated and found to be small. The experimental -values of the film agreed closely with the standard values.

  17. Synthesis and Characterization of Ce-Containing MCM-41

    Institute of Scientific and Technical Information of China (English)

    CHIEN; ShuHua

    2001-01-01

    SUMMARY.  The cerium-containing MCM-41 (Ce-MCM-41) has been synthesized with size in the micrometer range by direct hydrothermal method. Transmission electron microscopy shows the regular hexagonal array of uniform channel characteristics of MCM-41. Five peaks were detected in the lov-angle XRD patterns,an interplanar spacing d100 = 40.6 A was obtained that can be indexed on a hexagonal unit cell with a0 = 46.9 A. Nitrogen adsorption isotherm at 77 K revealed a surface area of 920 m2/g, pore size of 26.2 A and wall thickness of 18.1 A. A cell contraction of 2.6 A upon calcination was observed. The spectroscopic studies indicate that the synthesized sample is with MCM-41 structure and Ce is in the framework position. A weak Lewis acidity was indicated by infrared spectra of pyridine adsorption. The synthesized Ce-MCM-41 exhibits fairly catalytic activity for the NO reduction by CO.  ……

  18. Synthesis and Characterization of Ce-Containing MCM-41

    Institute of Scientific and Technical Information of China (English)

    CHIEN ShuHua; CHEN ChunLong

    2001-01-01

    @@ SUMMARY. The cerium-containing MCM-41 (Ce-MCM-41) has been synthesized with size in the micrometer range by direct hydrothermal method. Transmission electron microscopy shows the regular hexagonal array of uniform channel characteristics of MCM-41. Five peaks were detected in the lov-angle XRD patterns,an interplanar spacing d100 = 40.6 A was obtained that can be indexed on a hexagonal unit cell with a0 = 46.9 A. Nitrogen adsorption isotherm at 77 K revealed a surface area of 920 m2/g, pore size of 26.2 A and wall thickness of 18.1 A. A cell contraction of 2.6 A upon calcination was observed. The spectroscopic studies indicate that the synthesized sample is with MCM-41 structure and Ce is in the framework position. A weak Lewis acidity was indicated by infrared spectra of pyridine adsorption. The synthesized Ce-MCM-41 exhibits fairly catalytic activity for the NO reduction by CO.

  19. A simple modeling study of the Ce(IV) regeneration in sulfuric acid solutions

    International Nuclear Information System (INIS)

    Highlights: → The simple model of electrochemical regeneration of Ce(IV) in sulfuric acid solutions at PbO2 anode has been developed. → The study showed that Ce(SO4)2- is the kinetically active species and the decomposition of surface complex of Ce(IV) at the anode surface is the rate determining step. → There is no relation between current density and concentrations of ions participating in the anodic reaction. - Abstract: The electrochemical regeneration of Ce(IV) for mediated electrochemical oxidation in sulfuric acid media was investigated in an electrolytic membrane reactor. A simple kinetic model was developed to analyze and simulate the regeneration of Ce(IV) in the electrolysis process. The model was based on the Faraday's law and the mass balance of components in the reactor. The key operating conditions of the initial electrolyte concentration and the regeneration time were analyzed. It was found that the simulating model agreed well with the experimental data for regeneration of Ce(IV). Experimental results showed that Ce(SO4)2- is the active species. The decomposition of surface complex of Ce(IV) at the anode surface is the rate determining step. Constant-current electrolysis shows that the high proton and Ce(III) concentrations are electrochemically favorable for the regeneration of Ce(IV). The current efficiency for regeneration of Ce(IV) decrease obviously with the increase of SO42- concentration from 0.8 to 2.4 mol/L.

  20. Preparation and characterization of CNT-CeO{sub 2} nanocomposite

    Energy Technology Data Exchange (ETDEWEB)

    Kaur, Jasmeet, E-mail: jasmeet.dayal@gmail.com; Anand, Kanika; Singh, Ravi Chand [Department of Physics, Guru Nanak Dev University, Amritsar-143005 (India)

    2015-06-24

    This paper reports decoration of CeO{sub 2} nanoparticles on multi-walled carbon nanotubes through a reflux process in which Ce (NO{sub 3}) {sub 3}·6H{sub 2}O serves as precursor and hydrazine hydrate (N{sub 2}H{sub 4}.H{sub 2}O) as reducing agent. Successful deposition of cubic fluorite CeO{sub 2} nanoparticles onto multi-walled carbon nanotubes has been confirmed by x-ray diffraction (XRD), Raman spectroscopy, field-emission scanning electron microscopy (FE-SEM) and energy dispersive x-ray spectroscopy (EDS). It was found that CeO{sub 2} nanoparticles formed in the presence of CNTs were larger as compared to pure CeO{sub 2} nanoparticles. Raman analysis showed that CeO{sub 2} induced a decrease in the size of the carbon grain in the CNTs. A red shift from 460 cm{sup −1} to 463 cm{sup −1} for F{sub 2g} mode of CeO{sub 2} has also been observed in Raman spectra of CNT- CeO{sub 2} nanocomposite as compared to pure CeO{sub 2}. The CeO{sub 2} coated multi-wall carbon nanotubes (CNT-CeO{sub 2}) nanocomposite would be a promising candidate for practical applications such as catalysis, sensing and power source applications.

  1. Oxygen non-stoichiometries in (Th0.7Ce0.3)O2-x

    International Nuclear Information System (INIS)

    Oxygen non-stoichiometry in (Th0.7Ce0.3)O2-x oxide solid solutions was investigated from the viewpoint of Ce reduction. The oxygen non-stoichiometry was experimentally determined by means of thermogravimetric analysis as a function of oxygen potential at 1173, 1273 and 1373 K. Features of the isotherms of oxygen non-stoichiometry in (Th0.7Ce0.3)O2-x similar to those in oxygen non-stoichiometric actinide and lanthanide dioxides were observed. The oxygen non-stoichiometry in (Th0.7Ce0.3)O2-x was compared with those of CeO2-x and (U0.7Ce0.3)O2-x. It was concluded that the Ce reduction has some relation to defect forms and their transformations in the solid solutions.

  2. Isolation of several metastable phases in Ce-Gd-Zr-O system

    International Nuclear Information System (INIS)

    Cerium based zirconates pyrochlore; Ce2Zr2O7 attracts special attention due to potential catalytic application of CeO2-ZrO2 system in various chemical reactions. The mechanistic studies revealed that oxygen stoichiometry between CeO2 and Ce2O3 plays an important role in Ce2Zr2O7 for oxygen storage and release at relatively lower temperature by fluctuation of oxidation state of cerium. The crystal chemical properties of CeO2-ZrO2 system studied under different redox conditions indicate that the pyrochlore lattice can be maintained by a mild oxygen intercalation. The instability of the stoichiometric CeO2-ZrO2 system with pyrochlore structure imposes a major challenge on the synthetic methods. Several metastable phases have been isolated, for the first time, by adopting various modified reaction parameters

  3. Electrorheological Performance of SiO2 Particle Materials of Ce-Doping and Adsorbed Chitosan

    Institute of Scientific and Technical Information of China (English)

    Li Shuxin; Ma Shuzhen; Xu Mingyuan; Shang Yanli; Li Junran; Zhang Shaohua; Zhang Yuanjing; Gao Song

    2004-01-01

    The electrorheological(ER) materials of pure SiO2 ( Sample 1 ), Ce-doping SiO2 ( Ce-SiO2, Sample 2) and Ce-SiO2 adsorbed chitosan (Ce-SiO2-chitosan, Sample 3 ) were prepared using Na2SiO3, Ce( NO3 )3 and chitosan as starting materials. Their ER properties were studied. The results show that Ce-doping can enhance the ER activity of SiO2, and the ER activity of SiO2 can be further improved by adsorbing chitosan on the surfaces of Ce-SiO2 particles.The ER activity of a particle material is correlated with the average grain size, surface area, pore volume and average pore size of the material.

  4. Heat-treatment-induced luminescence degradation in Tb3+-doped CePO4 nanorods

    International Nuclear Information System (INIS)

    CePO4:Tb nanorods were synthesized via a simple wet-chemical route. The as-synthesized CePO4:Tb nanorods present high photoluminescence efficiency due to an efficient energy transfer form Ce3+ to Tb3+. However, heat treatment at 150 deg. C in air leads to a significant decrease of photoluminescence. X-ray photoelectron spectroscopy and excitation spectra revealed the oxidation of Ce3+ to Ce4+ in the heat-treatment process, which should be responsible for significant photoluminescence degradation due to the breakage of Ce3+→Tb3+ energy transfer. This conclusion is further supported by atmosphere and size effects of photoluminescence of CePO4:Tb under the heat treatment.

  5. New CeMgCo{sub 4} and Ce{sub 2}MgCo{sub 9} compounds: Hydrogenation properties and crystal structure of hydrides

    Energy Technology Data Exchange (ETDEWEB)

    Denys, R.V.; Riabov, A.B. [Karpenko Physico-Mechanical Institute NAS Ukraine, 5, Naukova Street, Lviv, 79000 (Ukraine); Cerny, R., E-mail: alexr@ipm.lviv.ua [Laboratory of Crystallography, University of Geneva, 24, Quai Ansermet, Geneva (Switzerland); Koval' chuk, I.V.; Zavaliy, I.Yu. [Karpenko Physico-Mechanical Institute NAS Ukraine, 5, Naukova Street, Lviv, 79000 (Ukraine)

    2012-03-15

    Two new ternary intermetallic compounds, CeMgCo{sub 4} (C15b pseudo-Laves phase, MgCu{sub 4}Sn type) and Ce{sub 2}MgCo{sub 9} (substitution derivative of PuNi{sub 3} type) were synthesized by mechanical alloying method. The structural and hydrogenation properties of these compounds were studied by X-ray diffraction and Pressure-Composition-Temperature measurements. Both compounds absorb hydrogen at room temperature and pressures below 10 MPa forming hydrides with maximum compositions CeMgCo{sub 4}H{sub 6} and Ce{sub 2}MgCo{sub 9}H{sub 12}. Single plateau behavior was observed in P-C isotherm during hydrogen absorption/desorption by Ce{sub 2}MgCo{sub 9} alloy. The CeMgCo{sub 4}-H{sub 2} system is characterized by the presence of two absorption/desorption plateaus corresponding to formation of {beta}-CeMgCo{sub 4}H{sub 4} and {gamma}-CeMgCo{sub 4}H{sub 6} hydride phases. The structure of {beta}-hydride CeMgCo{sub 4}H(D){sub 4} was determined from X-ray and neutron powder diffraction data. In this structure initial cubic symmetry of CeMgCo{sub 4} is preserved and hydrogen atoms fill only one type of interstitial sites, triangular MgCo{sub 2} faces. These positions are occupied by 70% and form octahedron around Mg atom with Mg-D bond distances 1.84 A. - Graphical abstract: Crystal structure of the {beta}-CeMgCo{sub 4}D{sub 4.2} deuteride. Octahedra of D-sites around Mg atoms are shown. Highlights: Black-Right-Pointing-Pointer Two new ternary compounds have been synthesized in the Ce-Mg-Co system. Black-Right-Pointing-Pointer Below 100 bar H{sub 2} CeMgCo{sub 4} and Ce{sub 2}MgCo{sub 9} reversibly absorb hydrogen at room temperature. Black-Right-Pointing-Pointer Crystal structure of cubic CeMgCo{sub 4}D{sub 4.2} deuteride has been determined.

  6. Efeito de inseticidas em insetos predadores em culturas de algodão Effect of insecticides on predator insects associated with cotton

    Directory of Open Access Journals (Sweden)

    JOSÉ JANDUI SOARES

    2000-09-01

    Full Text Available Com o objetivo de verificar o efeito de inseticidas em insetos predadores em cultura de algodão (Gossypium hirsutum L., instalaram-se, em 1993-1994, dois experimentos, um no campo, e outro, em laboratório. No experimento realizado no campo, os tratamentos foram: Fipronil 200 SC (75 g/ha de i.a.; Fipronil 800 WDG (64, 80 e 100 g/ha de i.a.; Endosulfan 350 CE (700 g/ha de i.a.; e testemunha. Em laboratório, além das formulações à base de Fipronil foi utilizado o Paration metílico 600 CE (480 g/ha de i.a.. Fipronil foi seletivo para os artrópodes predadores (Scymnus sp., Geocoris ventralis, Cycloneda sanguinea e Doru lineare no campo, e a Cycloneda sanguinea (L., em laboratório, e pode ser recomendado em programas de manejo integrado de pragas na cultura do algodoeiro para o controle de Alabama argillacea (Rueb., e Anthonomus grandis Boh. Endosulfan foi seletivo em relação a Scymnus sp., Geocoris ventralis Thomazini e Doru lineare (Eschs no campo, com uma redução dos insetos inferior a 30%, e o Paration metílico não foi seletivo para C. sanguinea em laboratório.To assess the selectivity of insecticides to predator insects in cotton (Gossypium hirsutum L. crops two, trials, 1993-1994, under field and laboratory conditions were conducted. Under field conditions, the following treatments were compared: Fipronil 200 CS (75 g/ha of a.i.; Fipronil 800 WDG (64, 80 and 100 g/ha of a.i.; Endosulfan 350 EC (700 g/ha of a.i.; and control. Under laboratory conditions, in addition to Friponil, Methyl parathion 600 EC 480 g/ha of a.i. was also tested. Fipronil was selective to predators (Scymnus sp., Geocoris ventralis, Cycloneda sanguinea and Doru lineare under field condition and to Cycloneda sanguinea (L. under laboratory conditions. This product can be used in integrated pest management programs in cotton crops to control Alabama argillacea (Rueb., and Anthonomus grandis Boh. Endosulfan was selective to Scymnus sp., Geocoris ventralis

  7. <em>In Vivoem> Histamine Optical Nanosensors

    Directory of Open Access Journals (Sweden)

    Heather A. Clark

    2012-08-01

    Full Text Available In this communication we discuss the development of ionophore based nanosensors for the detection and monitoring of histamine levels <em>in vivoem>. This approach is based on the use of an amine-reactive, broad spectrum ionophore which is capable of recognizing and binding to histamine. We pair this ionophore with our already established nanosensor platform, and demonstrate <em>in vitroem> and <em>in vivoem> monitoring of histamine levels. This approach enables capturing rapid kinetics of histamine after injection, which are more difficult to measure with standard approaches such as blood sampling, especially on small research models. The coupling together of <em>in vivoem> nanosensors with ionophores such as nonactin provide a way to generate nanosensors for novel targets without the difficult process of designing and synthesizing novel ionophores.

  8. Ação de produtos fitossanitários utilizados em cafeeiros sobre pupas e adultos de Chrysoperla externa (Hagen, 1861 (Neuroptera: Chrysopidae

    Directory of Open Access Journals (Sweden)

    Silva Rogério Antônio

    2006-01-01

    Full Text Available Avaliou-se a ação de produtos fitossanitários usados em cafeeiros sobre pupas e adultos de Chrysoperla externa (Hagen, 1861 (Neuroptera: Chrysopidae. Os bioensaios foram conduzidos no Departamento de Entomologia da Universidade Federal de Lavras - UFLA, Lavras, MG, Brasil. Os tratamentos avaliados, em g i.a.L-1 de água, foram: 1- endosulfan (Thiodan 350 CE - 1,75, 2- chlorpyrifos (Lorsban 480 CE -1,2, 3- betacyfluthrin (Turbo 50 CE - 0,013, 4- enxofre (Kumulus 800 PM - 4,0, 5- azocyclotin (Peropal 250 PM - 0,31, 6- oxicloreto de cobre (Cuprogarb 500 PM - 5,0 e 7- Testemunha (água. As pulverizações foram realizadas diretamente sobre pupas e adultos do crisopídeo por meio de torre de Potter. As pupas foram colocadas em tubos de vidro e os adultos em gaiolas de PVC, e mantidos em sala climatizada a 25 ? 2degreesC, UR de 70 ? 10% e fotofase de 12 horas. O delineamento experimental foi inteiramente casualizado, com sete tratamentos e dez repetições, sendo cada parcela formada por quatro pupas ou um casal de C. externa. Os produtos foram distribuídos nas quatro classes de toxicidade conforme escala estabelecida pela IOBC. O chlorpyrifos mostrou-se levemente nocivo para pupas (classe 2, 30?E?79%, e os demais produtos foram inócuos (classe 1, E99%. Os produtos testados à base de endosulfan, enxofre, azocyclotin e oxicloreto de cobre podem ser recomendados em programas de manejo de pragas do cafeeiro em associação com C. externa, em função da baixa toxidade apresentada por esses compostos ao predador.

  9. Effects of Ce additions on the age hardening response of Mg–Zn alloys

    International Nuclear Information System (INIS)

    The effects of Ce additions on the precipitation hardening behaviour of Mg–Zn are examined for a series of alloys, with Ce additions at both alloying and microalloying levels. The alloys are artificially aged, and studied using hardness measurement and X-ray diffraction, as well as optical and transmission electron microscopy. It is found that the age-hardening effect is driven by the formation of fine precipitates, the number density of which is related to the Zn content of the alloy. Conversely, the Ce content is found to slightly reduce hardening. When the alloy content of Ce is high, large secondary phase particles containing both Ce and Zn are present, and remain stable during solutionizing. These particles effectively reduce the amount of Zn available as solute for precipitation, and thereby reduce hardening. Combining hardness results with thermodynamic analysis of alloy solute levels also suggests that Ce can have a negative effect on hardening when present as solutes at the onset of ageing. This effect is confirmed by designing a pre-ageing heat treatment to preferentially remove Ce solutes, which is found to restore the hardening capability of an Mg–Zn–Ce alloy to the level of the Ce-free alloy. - Highlights: • The effects of Ce additions on precipitation in Mg–Zn alloys are examined. • Additions of Ce to Mg–Zn slightly reduce the age-hardening response. • Ce-rich secondary phase particles deplete the matrix of Zn solute. • Hardening is also decreased when Ce is present in solution. • Pre-ageing to preferentially precipitate out Ce restores hardening capabilities

  10. Preparation and thermochromic properties of Ce-doped VO{sub 2} films

    Energy Technology Data Exchange (ETDEWEB)

    Song, Linwei [College of Materials Science and Engineering, Sichuan University, Chengdu 610064 (China); Zhang, Yubo [College of Materials Science and Engineering, Sichuan University, Chengdu 610064 (China); Sichuan Engineering Technical College, Deyang 618000 (China); Huang, Wanxia, E-mail: huangwanxiascu@yahoo.com.cn [College of Materials Science and Engineering, Sichuan University, Chengdu 610064 (China); Shi, Qiwu; Li, Danxia; Zhang, Yang; Xu, Yuanjie [College of Materials Science and Engineering, Sichuan University, Chengdu 610064 (China)

    2013-06-01

    Graphical abstract: This effect of doping concentration on the phase transition temperature of VO{sub 2} films demonstrates that the phase transition temperature is decreasing along with the increase of the Ce dopant concentrations. After doping Ce, the transition temperature of VO{sub 2} film changes appreciably. Highlights: ► Ce-doped VO{sub 2} films were prepared on muscovite substrate by inorganic sol–gel method for the first time. ► The cerium existing in the VO{sub 2} films in the form of Ce{sup 4+} and Ce{sup 3+} was substituted for part of V atoms in the lattice. ► Ce doping could remarkably reduce the particle size of the Ce-doped films compared with undoped films. ► The phase transition temperature of Ce-doped VO{sub 2} films decreased appreciably with maintaining high-quality phase transition. - Abstract: Mixture of cerium (III) nitrate hexahydrate and vanadium pentaoxide powder were used as precursor to prepare Ce-doped VO{sub 2} films on the muscovite substrate by inorganic sol–gel method. SEM, XRD and XPS were used to investigate the morphologies and structures of VO{sub 2} films. The results show that the VO{sub 2} films grow on the muscovite substrate with preferred orientated (0 1 1) plane and the Ce exists in the form of Ce{sup 4+} and Ce{sup 3+} replacing part of V atoms in the lattice. The infrared transmittance change was measured from room temperature to the temperature above the metal–insulator transition. The films have excellent thermochromic performance. The metal–insulator transition temperature of VO{sub 2} films changes appreciably with Ce doped, which decreases by 4.5 °C per 1 at.% doping. Furthermore, Ce doping could remarkably reduce the particle size of VO{sub 2} films.

  11. Parasitic zoonoses: survey in foxes (<em>Vulpes vulpesem>) in the northern Apennines / Zoonosi parassitarie: indagini in volpi (<em>Vulpes vulpesem>) dell'Appennino settentrionale

    OpenAIRE

    Vittorio Guberti; Giovanni Poglayen

    1991-01-01

    Abstract A parasitological survey on 153 foxes was carried out in the northern Apennines, during the period 1984-1987. The following parasites were identified: <em>Toxocara canisem> (46.4%), <em>Taenia> sp. (17%), <em>Uncinaria stenocephalaem> (11.8%), <em>Mesocestoides lineatusem> (11.1%), <em>Ancylostoma caninumem> (3.9%), <em>Taenia hydatigenaem> (3.3%), <em>Trichuris v...

  12. Determinantes do aborto provocado entre mulheres admitidas em hospitais em localidade da região Nordeste do Brasil Determinants of iduced abortion among poor women admitted to hospitals in locality of the region northeast Brazil

    OpenAIRE

    Walter Fonseca; Chizuru Misago; Luciano L. Correia; João A. M. Parente; Francisco Chagas Oliveira

    1996-01-01

    Com o objetivo de identificar os determinantes do aborto provocado entre mulheres admitidas por complicações decorrentes dos abortos, nos hospitais-maternidades públicos em Fortaleza, CE (Brasil) foram entrevistadas 4.359 pacientes entre 1º de outubro de 1992 e 30 de setembro de 1993. Os dados foram coletados através de questionário estruturado. São apresentados os determinantes dos abortos provocados em 2.084 (48%) mulheres classificadas como tendo induzido aborto. Dois terços (66%) das mulh...

  13. Análise do estado de funcionalidade de idosos residentes em unidades de longa permanência

    OpenAIRE

    Jeanne Batista Josino; Rachel Belarmino Costa; Thiago Brasileiro de Vasconcelos; Bruno Ricarth Domiciano; Ismênia de Carvalho Brasileiro

    2015-01-01

    Objetivo: Analisar o estado de funcionalidade de idosos residentes em unidades de longa permanência. Métodos: Estudo descritivo-exploratório desenvolvido em duas instituições de longa permanência para idosos (ILPI) no município de Fortaleza-CE, no período de novembro de 2012 a julho de 2013. Os instrumentos utilizados foram: 1) formulário sociodemográfico, 2) Medida de Independência Funcional (MIF) e 3) Classificação Internacional de Funcionalidade (CIF). Os dados foram analisados de maneira ...

  14. Abnormal variation of magnetic properties with Ce content in (PrNdCe)2Fe14B sintered magnets prepared by dual alloy method

    Science.gov (United States)

    Xue-Feng, Zhang; Jian-Ting, Lan; Zhu-Bai, Li; Yan-Li, Liu; Le-Le, Zhang; Yong-Feng, Li; Qian, Zhao

    2016-05-01

    Resource-saving (PrNdCe)2Fe14B sintered magnets with nominal composition (PrNd)15‑x Ce x Fe77B8 (x = 0‑10) were prepared using a dual alloy method by mixing (PrNd)5Ce10Fe77B8 with (PrNd)15Fe77B8 powders. For Ce atomic percent of 1% and 2%, coercivity decreases dramatically. With further increase of Ce atomic percent, the coercivity increases, peaks at 6.38 kOe in (PrNd)11Ce4Fe77B8, and then declines gradually. The abnormal dependence of coercivity is likely related to the inhomogeneity of rare earth chemical composition in the intergranular phase, where PrNd concentration is strongly dependent on the additive amount of (PrNd)5Ce10Fe77B8 powders. In addition, for Ce atomic percent of 8%, 7%, and 6% the coercivity is higher than that of magnets prepared by the conventional method, which shows the advantage of the dual alloy method in preparing high abundant rare earth magnets. Project supported by the National Natural Science Foundation of China (Grant Nos. 51461033, 51571126, 51541105, and 11547032), the Natural Science Foundation of Inner Mongolia, China (Grant No. 2013MS0110), and the Inner Mongolia University of Science and Technology Innovation Fund, China.

  15. Temperature-dependent nonradiative energy transfer from Gd3+ to Ce3+ ions in co-doped LuAG:Ce,Gd garnet scintillators

    International Nuclear Information System (INIS)

    Energy transfer from donor Gd3+ to acceptor Ce3+ ions was studied in low doped lutetium aluminum garnet, LuAG:Ce,Gd. High purity single crystalline films were prepared by liquid phase epitaxy. The mechanism of nonradiative energy transfer from 6PJ (Gd3+) multiplet to crystal field split 5d2 (2D) states of Ce3+ was established as long-range dipole–dipole interaction and the average critical transfer distance between Gd3+ and Ce3+ ions was found ~14 Å at room temperature. It is shown that the single step energy transfer between donor–acceptor pairs is dominant while migration of excitation energy within the donor Gd3+ subsystem is only a small perturbation in the energy transfer mechanism in the studied low doped garnets. - Highlights: • Photoluminescence and decay kinetics in co-doped LuAG:Ce,Gd garnets. • Energy transfer from Gd3+ to Ce3+ in LuAG:Ce,Gd garnets. • Ce doped multicomponent garnet scintillators

  16. Temperature-dependent nonradiative energy transfer from Gd{sup 3+} to Ce{sup 3+} ions in co-doped LuAG:Ce,Gd garnet scintillators

    Energy Technology Data Exchange (ETDEWEB)

    Onderisinova, Z. [Charles University, Faculty of Mathematics and Physics, Ke Karlovu 5, 121 16 Prague 2 (Czech Republic); Kucera, M., E-mail: kucera@karlov.mff.cuni.cz [Charles University, Faculty of Mathematics and Physics, Ke Karlovu 5, 121 16 Prague 2 (Czech Republic); Hanus, M. [Charles University, Faculty of Mathematics and Physics, Ke Karlovu 5, 121 16 Prague 2 (Czech Republic); Nikl, M. [Institute of Physics, AS CR, Cukrovarnicka 10, 162 00 Prague 6 (Czech Republic)

    2015-11-15

    Energy transfer from donor Gd{sup 3+} to acceptor Ce{sup 3+} ions was studied in low doped lutetium aluminum garnet, LuAG:Ce,Gd. High purity single crystalline films were prepared by liquid phase epitaxy. The mechanism of nonradiative energy transfer from {sup 6}P{sub J} (Gd{sup 3+}) multiplet to crystal field split 5d{sub 2} ({sup 2}D) states of Ce{sup 3+} was established as long-range dipole–dipole interaction and the average critical transfer distance between Gd{sup 3+} and Ce{sup 3+} ions was found ~14 Å at room temperature. It is shown that the single step energy transfer between donor–acceptor pairs is dominant while migration of excitation energy within the donor Gd{sup 3+} subsystem is only a small perturbation in the energy transfer mechanism in the studied low doped garnets. - Highlights: • Photoluminescence and decay kinetics in co-doped LuAG:Ce,Gd garnets. • Energy transfer from Gd{sup 3+} to Ce{sup 3+} in LuAG:Ce,Gd garnets. • Ce doped multicomponent garnet scintillators.

  17. Crystal Growth and Intergrowth Structure of the New Heavy Fermion Materials CeIrIn 5 and CeRhIn 5

    Science.gov (United States)

    Moshopoulou, E. G.; Fisk, Z.; Sarrao, J. L.; Thompson, J. D.

    2001-04-01

    The structures of the new heavy fermion materials CeIrIn5 and CeRhIn5 have been determined by single-crystal neutron (R(F)=0.051) and X-ray (R(F)=0.056) diffraction, respectively. Both compounds adopt tetragonal structure, space group P4/mmm (No. 123), Z=1, a=b=4.674(1) Å, and c=7.501(5) Å for CeIrIn5, and a=b=4.656(2) Å, and c=7.542(1) Å for CeRhIn5. The possible presence of antisite disorder, a long-standing question on this type of structure, was excluded by both electron and-neutron or X-ray diffraction. The compounds are built by monolayers of face-sharing distorted cuboctahedra [CeIn3] and monolayers of edge-sharing rectangular parallelepipeds [RhIn2] or [IrIn2], stacked alternatively in the [001] direction. Therefore, they are new members of the inhomogeneous linear homologous series MmTnT‧3m+2n. Because of their ordered intergrowth structure, the physical properties of the quasi-two-dimensional heavy electron systems CeIrIn5 and CeRhIn5 can be directly compared with the corresponding ones of their parent compound, the three-dimensional heavy fermion material CeIn3.

  18. Glass forming ability of the Al-Ce-Ni system; Avaliacao da capacidade de formacao vitrea do sistema Al-Ce-Ni

    Energy Technology Data Exchange (ETDEWEB)

    Triveno Rios, C. [Engenharia Mecanica, Universidade Federal de Mato Grosso, Rondonopolis, MT (Brazil)], e-mail: triveno@ufmt.br; Surinach, S.; Baro, M.D. [Departamento de Engenharia de Materiais - Universidade Federal de Sao Carlos, SP (Brazil); Bolfarini, C.; Botta, W.J.; Kiminami, C.S. [Departamento de Fisica da Universidade Autonoma de Barcelona, Bellaterra (Spain)

    2010-07-01

    In the present work, the glass forming ability (GFA) and its compositional dependence on Al-Ni-Ce system alloys were investigated in function of several thermal parameters. Rapidly quenched Al{sub 85}Ni{sub 15}-{sub X}Ce{sub X} (X=4,5,6,7,10), Al{sub 90}Ni{sub 5}Ce{sub 5}, Al{sub 89}Ni{sub 2}.{sub 4}Ce{sub 8}.{sub 6}, Al{sub 80}Ni{sub 15.6}Ce{sub 4}.{sub 4} and Al{sub 78}Ni{sub 18.5}Ce{sub 3.5} amorphous ribbons were produced by melt-spinning and the structural transformation during heating was studied using a combination of X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The results showed that the GFA and the thermal stability in the Al-rich corner of Al- Ni-Ce system alloys were enhanced by increasing the solute content and specifically the Ce content (author)

  19. Scintillation response of YAlO3:Ce and Lu0.7Y0.3AlO3:Ce single crystal scintillators

    Science.gov (United States)

    Phunpueok, A.; Chewpraditkul, W.; Limsuwan, P.; Wanarak, C.

    2012-09-01

    The scintillation response of YAlO3:Ce (YAP:Ce) and Lu0.7Y0.3AlO3:Ce (LuYAP:Ce) crystals with same size of 10 × 10 × 5 mm3 were studied for gamma ray energies ranging from 22.1 to 1274.5 keV. The light yield, its non-proportionality and the energy resolution were measured with the photomultiplier tube (PMT). The intrinsic resolution of the crystals versus energy of gamma rays has been determined after correcting the measured energy resolution for photomultiplier tube statistics. For 662 keV gamma rays (137Cs source), the YAP:Ce showed the light yield of 32,000 ph/MeV,which is much higher than that of 9800 ph/MeV obtained for LuYAP:Ce. The energy resolution of 4.4% obtained for YAP:Ce is much better than that of 7.9% obtained for LuYAP:Ce, due to its much higher light yield and better intrinsic resolution. The scintillation light loss of tested crystals at 511 keV gamma rays (22Na source) was also presented. The estimated photofraction was determined for both crystals and compared with the cross-sections ratio calculated using WinXCom program. The experimental results of the total mass attenuation coefficients for both crystals are in good agreement with the theoretical values, within the experimental uncertainty.

  20. Burnout em cuidados paliativos

    OpenAIRE

    Simões, Sílvia Cristina Almeida

    2013-01-01

    Dissertação apresentada ao Instituto Politécnico de Castelo Branco para cumprimento dos requisitos necessário à obtenção de grau de Mestre em Cuidados Paliativos. O presente trabalho foi realizado no âmbito do 3º semestre do 1º Curso de Mestrado em Cuidados Paliativos, da Escola Superior de Saúde Dr. Lopes Dias. O trabalho encontra-se estruturado em quatro capítulos: o primeiro diz respeito ao relatório da prática clínica, o segundo aborda o enquadramento teórico sobre a Síndrome de Bur...

  1. Characterization of the structure features of CeZrO2 and Ni/CeZrO2 catalysts for tar gasification with steam

    Directory of Open Access Journals (Sweden)

    A. Krztoń

    2011-04-01

    Full Text Available Purpose: The aim of this study was to find out how CeZrO2 and Ni/CeZrO2 structures change after the steam reforming of toluene.Design/methodology/approach: Nickel oxide supported on CeZrO2 (Ni/CeZrO2 with nickel loading of 10 wt. % was prepared by incipient wetness impregnation using an aqueous solution of nickel nitrate. Structure, morphology and chemical composition changes after the steam reforming of toluene were investigated by means of scanning electron microscopy (SEM, energy dispersive X-ray spectroscopy (EDS and by X-ray diffraction (XRD measurements. Additionally, spent Ni/CeZrO2 was regenerated in O2 while the fresh Ni/CeZrO2 was subjected to two kinds of reduction: (i in hydrogen, in order to reduce NiO to Ni and (ii in toluene, in order to find if the reduction of NiO to Ni by C7H8 is followed by carbon deposition on metallic nickel.Findings: XRD results revealed the formation of a CeO2-ZrO2 solid solution with a cubic symmetry. Ni/CeZrO2 preparation results in the increase of crystallites in comparison to the size of the commercial CeZrO2. Reduction from NiO (200 to Ni (111 in samples reduced under hydrogen and toluene was confirmed while morphology of Ni/CeZrO2 remained unchanged. Ni/CeZrO2 reduced under toluene include large amount of carbon, deposited by decomposition of the hydrocarbon. Steam reforming of toluene not influence on morphology of investigated materials. Energy dispersive spectroscopy indicated larger amount of carbon residuals in sample after test in comparison to fresh Ni/CeZrO2. After regeneration in O2 carbon residuals were successfully removed.Practical implications: Nickel catalysts supported on ceria-zirconia can be efficiently applied in reforming reactions.Originality/value: CeZrO2 and Ni/CeZrO2 was selected as a model compound of tar from biomass gasification.

  2. Evaluation of Pseudopteroxazole and Pseudopterosin Derivatives against <em>Mycobacterium> <em>tuberculosis> and Other Pathogens

    OpenAIRE

    McCulloch, Malcolm W. B.; Brad Haltli; Marchbank, Douglas H.; Kerr, Russell G.

    2012-01-01

    Pseudopterosins and pseudopteroxazole are intriguing marine natural products that possess notable antimicrobial activity with a commensurate lack of cytotoxicity. New semi-synthetic pseudopteroxazoles, pseudopteroquinoxalines and pseudopterosin congeners along with simple synthetic mimics of the terpene skeleton were synthesized. In order to build structure-activity relationships, a set of 29 new and previously reported compounds was assessed for <em>in> <em>vitro...

  3. Enhancement of red to orange emission ratio of YPO4:Eu3+,Ce3+ and its dependence on Ce3+ concentration

    Institute of Scientific and Technical Information of China (English)

    ZHAN Shiping; GAO Yongyi; LIU Yunxin; ZHONG Hui

    2012-01-01

    Eu3+ and Ce3+ co-doped YPO4 microspheres were synthesized by hydrothermal method without template.The emission spectra showed that the red emission centered at 618 nm could be readily increased relatively to the orange emission centered at 590 nm by controlling the doping concentration of Ce3+ ion.The investigation based on excitation spectra and decay curves demonstrated that the doped Ce3+ ions took two efficient energy transfers to Eu3+ ions and affected the lifetime of the emission states ofEu3+ ions so that the emission spectra of Eu3+ ion were accordingly tuned with the Ce3+ content increasing.This controllable red (5D0→7F2) to orange (5D0→7F1) emission ratio of YPO4:Eu3+,Ce3+ made it very promising for encoded anti-fake labels and bio-labels.

  4. Investigation of structural and magnetic properties of Ce{sup 3+}-substituted nanosized Co–Cr ferrites for a variety of applications

    Energy Technology Data Exchange (ETDEWEB)

    Mustafa, Ghulam, E-mail: ghulammustafabzu@gmail.com [Department of Physics, Bahauddin Zakariya University, Multan 60800 (Pakistan); Islam, M.U. [Department of Physics, Bahauddin Zakariya University, Multan 60800 (Pakistan); Zhang, Wenli [State Key Laboratory of Electronic Thin Films and Integrated Devices, Chengdu 610054 (China); Jamil, Yasir [Department of Physics, University of Agriculture, Faisalabad 38040 (Pakistan); Anwar, Abdul Waheed [Department of Physics, University of Engineering and Technology, Lahore 54890 (Pakistan); Hussain, Mudassar [Department of Physics, Bahauddin Zakariya University, Multan 60800 (Pakistan); Ahmad, Mukhtar, E-mail: ahmadmr25@yahoo.com [Department of Physics, COMSATS Institute of Information Technology, Islamabad 44000 (Pakistan)

    2015-01-05

    Highlights: • Ce-substituted spinel ferrites synthesized by coprecipitation route have been investigated. • The average particle size was in the range of 30.8–63.7 nm estimated by Scherer formula. • Saturation magnetization values were decreased with increasing Ce contents. • Coercivity for all samples is suitable for recording media, switching and EM materials. - Abstract: Nanocrystalline samples of Ce{sup 3+} substituted Co–Cr ferrite with chemical formula CoCr{sub 0.04}Ce{sub x}Fe{sub 1.96−x}O{sub 4} (0 ⩽ x ⩽ 0.1) have been synthesized by co-precipitation method and sintered at a temperature of 850 °C for 8 h. The samples were characterized using thermo-gravimetric and differential thermal analysis, X-ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy, scanning electron microscopy, atomic force microscopy and vibrating sample magnetometry. The XRD patterns and FTIR spectra confirm that the prepared samples reveal the formation of spinel ferrites. The average particle size was found to be in the range of 30.8–63.7 nm estimated by Scherer formula. The lattice constant varies in the range of 8.352–8.382 Å due to difference in the ionic radii of the substituted cations. IR studies confirm two main absorption bands in the frequency range of 400–800 cm{sup −1} arising due to the tetrahedral (A-site) and octahedral (B-site) stretching vibrations. The elemental analysis as obtained from the EDXS measurement is in close agreement with the expected composition from the stoichiometry of the reactant solutions. The M–H loops show that the saturation magnetization decreased gradually with increasing Ce content, while the coercivity is related to the microstructure of Ce-substituted samples. The obtained results suggest that the investigated materials are potential candidates for magnetic recording media, security, switching and high frequency applications.

  5. Thermoelectric transport properties of nanostructured FeSb 2 and Ce-based heavy-fermions CeCu and CeAl 3

    Science.gov (United States)

    Pokharel, Mani R.

    Thermoelectric (TE) energy conversion is an all-solid-state technology which can convert waste thermal energy into useful electric power and cool ambience without using harmful gases like CFC. Due to their several advantages over traditional energy conversion technologies, thermoelectric generators (TEG) and coolers (TEC) have drawn enormous research efforts. The objective of this work is to find promising materials for thermoelectric cooling applications and optimize their thermoelectric performances. Finding a material with a good value for the thermoelectric figure-of-merit (ZT) at cryogenic temperatures, specifically below 77 K, has been of great interest. This work demonstrates that FeSb2 1, CeCu6 2 and CeAl3 3, all belonging to a class of materials with strongly correlated electron behavior; exhibit promising thermoelectric properties below 77 K. In general, ZT of a TE material can be increased using two basic approaches: lattice thermal conductivity reduction and power factor (PF) enhancement. The results of this study indicate that nanostructuring effectively decreases the thermal conductivity of FeSb2, CeCu6 and CeAl 3 leading to improved ZT. The approach of introducing point-defect scattering to further reduce the thermal conductivity is successfully implemented for Te-substituted FeSb2 nanostructured samples 4. A semiconductor/metal interface has long been proposed to exhibit enhanced thermoelectric properties. We use this technique by introducing Ag-nanoparticles in the host FeSb2 which further increases ZT by 70% 5. Additionally, a detailed investigation is made on the phonon-drag effect as a possible mechanism responsible for the large value of the Seebeck coefficient of FeSb2 6. We show that the phonon-drag mechanism contributes significantly to the large Seebeck effect in FeSb2 and hence this effect cannot be minor as was proposed in literatures previously. A model based on Kapitza-resistance and effective medium approach (EMA) is used to analyze

  6. Ulisses em Kafka

    Directory of Open Access Journals (Sweden)

    Stéphane Mosès

    2015-02-01

    Full Text Available ResumoEm sua introdução para Exegese de uma lenda, Stéphane Mosès afirma que a obra de Kafka não necessita de novas interpretações, mas sim de uma “análise rigorosa de sua lógica subjacente”. Assim, em “Ulisses em Kafka”, investigandoa dialética formal de “O silêncio das sereias”, Mosès procura expor a estrutura narrativa que comandaria esse breve texto em que o escritor tcheco acrescenta à astucia de Ulisses a ingenuidade como elemento de salvação.Palavras-chave: Kafka; dialética; salvação.AbstractIn his introduction to Exegèse d’une légende, Stéphane Mosès affirms that Kafka’s works are not in need of new interpretations, but rather, of a “rigorous analysis of their underlying logic”. Thus, in “Ulisses chez Kafka”, by investigating the formal dialectic of “Das Schweigen der Sirenen”, Mosès seeks to exhibit the narrative structure that would supposedly guide this short text in which the Czech author adds naïveté to Ulisses’s cunning intelligence as an element of salvation.Keywords: Kafka; dialectic; salvation.Stéphane Mosès foi professor emérito da Universidade Hebraica de Jerusalém, onde ensinou Literatura Alemã e Comparada, entre os seus principais interesses estavam o pensamento de Franz Rosenzweig e de Walter Benjamin e as literaturas de Franz Kafka e de Paul Célan. Autor de diversos livros, entre eles: L'ange de l'histoire. Rosenzweig, Benjamin, Scholem, Exégèse d'une légende, lectures de Kafka, e Rêves de Freud. Six lectures.Rodrigo Ielpo é doutor em literatura francesa pela UFRJ e em História e Semiologia do texto e da imagem pela Université Paris VII, com pós-doutorado em Teoria Literária pela UNICAMP. Professor Adjunto do Departamento de Letras Neolatinas da Universidade Federal do Rio de Janeiro, possui publicações e traduções nos seguintes temas: teoria e literatura francesa contemporâneas, escrita e processos de subjetivação.rodrigoielpo@gmail.com 

  7. Controllable preparation of CeO2 nanostructure materials and their catalytic activity

    Institute of Scientific and Technical Information of China (English)

    Shan Wenjuan; Guo Hongjuan; Liu Chang; Wang Xiaonan

    2012-01-01

    Well-crystalline CeO2 nanostructures with the morphology ofnanorods and nanocubes were synthesized by a template-free hydrothermal method.X-ray diffraction (XRD),transmission electron microscopy (TEM),Brunauer-Emmett-Teller (BET) nitrogen adsorption-desorption measurements were employed to characterize the synthesized materials.The reducibility and catalytic activity of nanostructured CeO2 were examined by hydrogen temperature-programmed reduction (H2-TPR) and CO oxidation.The results showed that CeO2 nanorods could be converted into CeO2 nanocubes with the increasing of the reaction time and the hydrothermal temperature,CeO2 nanorods became longer gradually with the increasing of the concentrations of NaOH.H2-TPR characterization demonstrated that the intense low-temperature reduction peak in the CeO2 nanorods indicated the amount of hydrogen consumed is larger than CeO2 nanocubes.Meantime the CeO2 nanorods enhanced catalytic activity for CO oxidation,the total conversion temperature was 340 ℃.The reasons were that CeO2 nanorods have much smaller crystalline sizes and higher surface areas than CeO2 nanocubes.

  8. Chemical interaction of Ce-Fe mixed oxides for methane selective oxidation

    Institute of Scientific and Technical Information of China (English)

    祝星; 杜云鹏; 王华; 魏永刚; 李孔斋; 孙令玥

    2014-01-01

    Chemical interaction of Ce-Fe mixed oxides was investigated in methane selective oxidation via methane temperature pro-grammed reduction and methane isothermal reaction tests over Ce-Fe oxygen carriers. In methane temperature programmed reduction test, Ce-Fe oxide behaved complete oxidation at the lower temperature and selective oxidation at higher temperatures. Ce-Fe mixed oxides with the Fe content in the range of 0.1-0.5 was able to produce syngas with high selectivity in high-temperature range (800-900 °C), and a higher Fe amount over 0.5 seemed to depress the CO formation. In isothermal reaction, complete oxidation oc-curred at beginning following with selective oxidation later. Ce1-xFexO2-δ oxygen carriers (x≤0.5) were proved to be suitable for the selective oxidation of methane. Ce-Fe mixed oxides had the well-pleasing reducibility with high oxygen releasing rate and CO selec-tivity due to the interaction between Ce and Fe species. Strong chemical interaction of Ce-Fe mixed oxides originated from both Fe* activated CeO2 and Ce3+ activated iron oxides (FeOm), and those chemical interaction greatly enhanced the oxygen mobility and se-lectivity.

  9. Luminescence enhancement of PPO/PVT scintillators by CeF{sub 3} nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Sahi, Sunil; Chen, Wei; Jiang, Ke

    2015-03-15

    Oleic acid coated cerium fluoride (CeF{sub 3}) nanoparticles were synthesized by a wet chemistry method. The average size of the nanoparticles is 12 nm, and the nanoparticles are dispersible in polyvinyl toluene (PVT) monomer due to the oleic acid coating. Different amounts of as-synthesized CeF{sub 3} nanoparticles are then loaded into PVT matrix with 0.5 wt% 2,5-diphenyloxazole (PPO) by bulk polymerization. The luminescence of PPO/PVT is enhanced by CeF{sub 3} nanoparticles to 3 and 2.5 times under UV and X-ray excitation, respectively. This enhancement is due to the energy transfer from CeF{sub 3} to PPO, the increase of the stopping power by doping CeF{sub 3} nanoparticles into PPO/PVT and the escape of charges from CeF{sub 3} nanoparticles. - Highlights: • Oleic acid coated cerium fluoride (CeF{sub 3}) nanoparticles were synthesized by a wet chemistry method. • The luminescence of PPO/PVT is enhanced by CeF{sub 3} nanoparticles under UV and X-ray excitations. • This enhancement is due to the energy transfer from CeF{sub 3} to PPO in PVT matrix. • The escape of charges from CeF{sub 3} nanoparticles also contribute to the luminescence enhancement. • These nanocomposite materials could be promising for radiation detection.

  10. Luminescence enhancement of PPO/PVT scintillators by CeF3 nanoparticles

    International Nuclear Information System (INIS)

    Oleic acid coated cerium fluoride (CeF3) nanoparticles were synthesized by a wet chemistry method. The average size of the nanoparticles is 12 nm, and the nanoparticles are dispersible in polyvinyl toluene (PVT) monomer due to the oleic acid coating. Different amounts of as-synthesized CeF3 nanoparticles are then loaded into PVT matrix with 0.5 wt% 2,5-diphenyloxazole (PPO) by bulk polymerization. The luminescence of PPO/PVT is enhanced by CeF3 nanoparticles to 3 and 2.5 times under UV and X-ray excitation, respectively. This enhancement is due to the energy transfer from CeF3 to PPO, the increase of the stopping power by doping CeF3 nanoparticles into PPO/PVT and the escape of charges from CeF3 nanoparticles. - Highlights: • Oleic acid coated cerium fluoride (CeF3) nanoparticles were synthesized by a wet chemistry method. • The luminescence of PPO/PVT is enhanced by CeF3 nanoparticles under UV and X-ray excitations. • This enhancement is due to the energy transfer from CeF3 to PPO in PVT matrix. • The escape of charges from CeF3 nanoparticles also contribute to the luminescence enhancement. • These nanocomposite materials could be promising for radiation detection

  11. Origin of enhanced photocatalytic activity of F-doped CeO2 nanocubes

    Science.gov (United States)

    Miao, Hui; Huang, Gui-Fang; Liu, Jin-Hua; Zhou, Bing-Xin; Pan, Anlian; Huang, Wei-Qing; Huang, Guo-Fang

    2016-05-01

    CeO2 nanoparticles are synthesized using a low-temperature solution combustion method and subsequent heat treatment in air. It is found that F-doping leads to smaller particle size and the formation of CeO2 nanocubes with higher percentage of reactive facets exposed. The band gap is estimated to be 3.16 eV and 2.88 eV, for pure CeO2 and fluorine doped CeO2 (F-doped CeO2) nanocubes, respectively. The synthesized F-doped CeO2 nanocubes exhibit much higher photocatalytic activities than commercial TiO2 and spherical CeO2 for the degradation of MB dye under UV and visible light irradiation. The apparent reaction rate constant k of MB decomposition over the optimized F-doped CeO2 nanocubes is 9.5 times higher than that of pure CeO2 and 2.2 times higher than that of commercial TiO2. The enhanced photocatalytic activity of F-doped CeO2 nanocubes originates from the fact that F-doping induces the small size, the highly reactive facets exposed, the intense absorption in the UV-vis range and the narrowing of the band gap. This research provides some new insights for the synthesis of the doping of the foreign atoms into photocatalyst with controlled morphology and enhanced photocatalytic activity.

  12. Microstructures and mechanical properties in B{sub 4}C-CeO{sub 2} ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Sun Shuchen, E-mail: sunsc@smm.neu.edu.cn [School of Materials and Metallurgy, Northeastern University, Shenyang 110004 (China); Sakamoto, Tatsuaki; Nakai, Kiyomichi [Department of Materials Science and Biotechnology, Ehime University, 3Bunkyo-cho, Matsuyama 790-8577 (Japan); Kurishita, Hiroaki [International Research Center for Nuclear Materials Science, Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313 (Japan); Kobayashi, Sengo [Department of Materials Science and Biotechnology, Ehime University, 3Bunkyo-cho, Matsuyama 790-8577 (Japan); Xu Jingyu; Cao Hui; Gao Bo; Bianxue; Wu Wenyuan; Tu Ganfeng [School of Materials and Metallurgy, Northeastern University, Shenyang 110004 (China); Matsuda, Seiji [Department of Anatomy and Embryology, Ehime University, Shizugawa, Toon 791-0295 (Japan)

    2011-10-01

    B{sub 4}C-CeO{sub 2} composite ceramics with various concentrations of CeO{sub 2} were fabricated by hot press. The effects of CeO{sub 2} on the microstructures and mechanical properties of the B{sub 4}C-CeO{sub 2} ceramics have been investigated. During hot press, CeB{sub 6} was formed by the reaction between CeO{sub 2} and B{sub 4}C. The B{sub 4}C-CeO{sub 2} ceramics had higher levels of density, fracture toughness, flexural strength and Vickers hardness than those in monolithic B{sub 4}C. The microstructures of the B{sub 4}C-CeO{sub 2} ceramics were observed and analyzed by transmission electron microscopy. In-situ synthesized CeB{sub 6} indicated whisker-like shape and grew along the interface with B{sub 4}C, and different boron carbides with different content of C existed at/around the interface of CeB{sub 6} with B{sub 4}C in the composite ceramics. It made mechanical properties greatly improved.

  13. Horizontal Transmission of the Entomopathogen Fungus <em>Metarhizium anisopliae em>in <em>Microcerotermes diversusem> Groups

    Directory of Open Access Journals (Sweden)

    Mohammad Saied Mossadegh

    2012-08-01

    Full Text Available An experiment was carried out in order to investigate fungal conidia transmission of <em>Metarhizium anisopliae em>(Metschnikoff> em>Sorokin from vector (donor to healthy <em>Microcerotermes diversusem> Silvestri (Iso.: Termitidae and determine the best donor/concentration ratio for transmission. After preliminary trials, concentrations of 3.1 × 104, 3.9 × 105, 3.2 × 106 and 3.5 × 108 conidia mL−1 were selected for testing. The experiment was performed at three donor : Recipient ratios of 10, 30 and 50%. The highest mortality of recipient workers was observed after 14 days at the concentration of 3.5 × 108 conidia mL−1 and donor ratio of 50%. The mortality of recipient workers was less than 20% at all concentrations at a donor ratio of 10%. Our observations indicate social behavior of <em>M. diversusem>, such as grooming, can be effective in promoting epizootic outbreaks in a colony. While the current results suggest good potential for efficacy, the use of <em>M. anisopliaeem> as a component of integrated pest management of <em>M. diversusem> still needs to be proven under field conditions.

  14. Manipulating Ce Valence in RE2Fe14B Tetragonal Compounds by La-Ce Co-doping: Resultant Crystallographic and Magnetic Anomaly

    Science.gov (United States)

    Jin, Jiaying; Zhang, Yujing; Bai, Guohua; Qian, Zeyu; Wu, Chen; Ma, Tianyu; Shen, Baogen; Yan, Mi

    2016-01-01

    Abundant and low-cost Ce has attracted considerable interest as a prospective alternative for those critically relied Nd/Pr/Dy/Tb in the 2:14:1-type permanent magnets. The (Nd, Ce)2Fe14B compound with inferior intrinsic magnetic properties to Nd2Fe14B, however, cannot provide an equivalent magnetic performance. Since Ce valence is sensitive to local steric environment, manipulating it towards the favorable trivalent state provides a way to enhance the magnetic properties. Here we report that such a desirable Ce valence can be induced by La-Ce co-doping into [(Pr, Nd)1−x(La, Ce)x]2.14Fe14B (0 ≤ x ≤ 0.5) compounds via strip casting. As verified by X-ray photoelectron spectroscopy results, Ce valence shifts towards the magnetically favorable Ce3+ state in the composition range of x > 0.3, owing to the co-doping of large radius La3+ into 2:14:1 phase lattice. As a result, both crystallographic and magnetic anomalies are observed in the same vicinity of x = 0.3, above which lattice parameters a and c, and saturation magnetization Ms increase simultaneously. Over the whole doping range, 2:14:1 tetragonal structure forms and keeps stable even at 1250 K. This finding may shed light on obtaining a favorable Ce valence via La-Ce co-doping, thus maintaining the intrinsic magnetic properties of 2:14:1-type permanent magnets. PMID:27457408

  15. Manipulating Ce Valence in RE2Fe14B Tetragonal Compounds by La-Ce Co-doping: Resultant Crystallographic and Magnetic Anomaly.

    Science.gov (United States)

    Jin, Jiaying; Zhang, Yujing; Bai, Guohua; Qian, Zeyu; Wu, Chen; Ma, Tianyu; Shen, Baogen; Yan, Mi

    2016-01-01

    Abundant and low-cost Ce has attracted considerable interest as a prospective alternative for those critically relied Nd/Pr/Dy/Tb in the 2:14:1-type permanent magnets. The (Nd, Ce)2Fe14B compound with inferior intrinsic magnetic properties to Nd2Fe14B, however, cannot provide an equivalent magnetic performance. Since Ce valence is sensitive to local steric environment, manipulating it towards the favorable trivalent state provides a way to enhance the magnetic properties. Here we report that such a desirable Ce valence can be induced by La-Ce co-doping into [(Pr, Nd)1-x(La, Ce)x]2.14Fe14B (0 ≤ x ≤ 0.5) compounds via strip casting. As verified by X-ray photoelectron spectroscopy results, Ce valence shifts towards the magnetically favorable Ce(3+) state in the composition range of x > 0.3, owing to the co-doping of large radius La(3+) into 2:14:1 phase lattice. As a result, both crystallographic and magnetic anomalies are observed in the same vicinity of x = 0.3, above which lattice parameters a and c, and saturation magnetization Ms increase simultaneously. Over the whole doping range, 2:14:1 tetragonal structure forms and keeps stable even at 1250 K. This finding may shed light on obtaining a favorable Ce valence via La-Ce co-doping, thus maintaining the intrinsic magnetic properties of 2:14:1-type permanent magnets. PMID:27457408

  16. Mesoporous CeTiSiMCM-48 as novel photocatalyst for degradation of organic compounds

    International Nuclear Information System (INIS)

    This work presents novel photocatalysts containing Ti and/or Ce embedded in the mesoporous silica framework (TiSiMCM-48, CeSiMCM-48 and CeTiSiMCM-48) that were prepared via a facile sol–gel process in the presence of ionic structure directing agents. The structural properties of the obtained materials were analyzed by X-ray diffraction (XRD), nitrogen adsorption-desorption, scanning and transmission electron microscopy (SEM, TEM), EDAX analysis, X-ray photoelectron microscopy (XPS), ultraviolet–visible diffuse reflectance spectroscopy (UV–vis DRS) and Fourier transformation infrared spectroscopy (FT-IR). The results indicated that Ce and Ti were highly dispersed or incorporated into the framework of the cubic SiMCM-48, with an enhanced light-trapping effect both in the UV and Vis regions. When applied to the photocatalytic degradation of phenol, the best results were obtained for the bimetallic hybrid. The best activity of CeTiSiMCM-48 photocatalyst was ascribed to improved electron–hole pair separation efficiency and formation of more reactive oxygen species due to the presence of Ce4+/Ce3+. The mesoporous support increases the dispersability of the photoactive Ti4+ or Ce4+/Ce3+ species on the catalyst surface and the accessibility of the substrate to the active sites. Furthermore, the catalysts can be easily recovered and reused for four cycles without significant loss of activity. - Highlights: • Novel photocatalysts containing Ti and/or Ce embedded in the mesoporous MCM-48 silica. • Ce4+/Ce3+ improved electron–hole pair separation and reactivity of oxygen species. • The mesoporous support increases the dispersability of the photoactive species. • The photocatalyst was highly active and stable for phenol degradation under UV irradiation. • TiCeSiMCM-48 can be recycled up to four cycles without significant loss of activity

  17. Mesoporous CeTiSiMCM-48 as novel photocatalyst for degradation of organic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Mureseanu, Mihaela, E-mail: mihaela_mure@yahoo.com [Faculty of Chemistry, University of Craiova, 107 I Calea Bucureşti, 200478 Craiova (Romania); Parvulescu, Viorica, E-mail: vpirvulescu@icf.ro [“Ilie Murgulescu” Institute of Physical Chemistry, Romanian Academy, Spl. Independentei 202, 060021 Bucharest (Romania); Radu, Teodora, E-mail: teocluj@gmail.com [National Institute for Research and Development of Isotopic and Molecular Technologies, 65-103 Donath Street, 400293 Cluj Napoca (Romania); Institute of Interdisciplinary Research in Bio-Nano-Sciences, Babes Bolyai University, 400271 Cluj-Napoca (Romania); Filip, Mihaela [“Ilie Murgulescu” Institute of Physical Chemistry, Romanian Academy, Spl. Independentei 202, 060021 Bucharest (Romania); Carja, Gabriela, E-mail: carja@uaic.ro [Faculty of Chemical Engineering and Environmental Protection, Technical University of Iasi, 71 D. Mangeron, Iasi (Romania)

    2015-11-05

    This work presents novel photocatalysts containing Ti and/or Ce embedded in the mesoporous silica framework (TiSiMCM-48, CeSiMCM-48 and CeTiSiMCM-48) that were prepared via a facile sol–gel process in the presence of ionic structure directing agents. The structural properties of the obtained materials were analyzed by X-ray diffraction (XRD), nitrogen adsorption-desorption, scanning and transmission electron microscopy (SEM, TEM), EDAX analysis, X-ray photoelectron microscopy (XPS), ultraviolet–visible diffuse reflectance spectroscopy (UV–vis DRS) and Fourier transformation infrared spectroscopy (FT-IR). The results indicated that Ce and Ti were highly dispersed or incorporated into the framework of the cubic SiMCM-48, with an enhanced light-trapping effect both in the UV and Vis regions. When applied to the photocatalytic degradation of phenol, the best results were obtained for the bimetallic hybrid. The best activity of CeTiSiMCM-48 photocatalyst was ascribed to improved electron–hole pair separation efficiency and formation of more reactive oxygen species due to the presence of Ce{sup 4+}/Ce{sup 3+}. The mesoporous support increases the dispersability of the photoactive Ti{sup 4+} or Ce{sup 4+}/Ce{sup 3+} species on the catalyst surface and the accessibility of the substrate to the active sites. Furthermore, the catalysts can be easily recovered and reused for four cycles without significant loss of activity. - Highlights: • Novel photocatalysts containing Ti and/or Ce embedded in the mesoporous MCM-48 silica. • Ce{sup 4+}/Ce{sup 3+} improved electron–hole pair separation and reactivity of oxygen species. • The mesoporous support increases the dispersability of the photoactive species. • The photocatalyst was highly active and stable for phenol degradation under UV irradiation. • TiCeSiMCM-48 can be recycled up to four cycles without significant loss of activity.

  18. Hydrothermal synthesis of hexagonal CeO{sub 2} nanosheets and their room temperature ferromagnetism

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Fanming, E-mail: mrmeng@ahu.edu.cn [School of Physics and Materials Science, Anhui University, Hefei 230601 (China); Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Dalian University of Technology, Ministry of Education, Dalian 116024 (China); Zhang, Cheng; Fan, Zhenghua; Gong, Jinfeng; Li, Aixia; Ding, Zongling; Tang, Huaibao; Zhang, Miao; Wu, Guifang [School of Physics and Materials Science, Anhui University, Hefei 230601 (China)

    2015-10-25

    Hexagonal CeO{sub 2} nanosheets of 40–50 nm in thickness and 300–400 nm in side-length have been successfully synthesized via controlling the morphology of CeCO{sub 3}OH precursors by a facile hydrothermal technique using CeCl{sub 3}·7H{sub 2}O as cerium source, ammonium hydrogen carbonate as precipitants, and ethylenediamine as complexant. The reaction time and the amount of CeCl{sub 3}·7H{sub 2}O and ethylenediamine were systematically investigated. The as-synthesized hexagonal CeO{sub 2} nanosheets were examined by XRD, SEM, TEM, XPS, Raman scattering and magnetization measurements. It is found that the amount of CeCl{sub 3}·7H{sub 2}O and ethylenediamine are key parameters for controlling the final morphology. The hexagonal CeO{sub 2} nanosheets have a fluorite cubic structure and there are Ce{sup 3+} ions and oxygen vacancies in surface of samples. The synthesized CeO{sub 2} shows excellent room temperature optical properties. M–H curve exhibits excellent room-temperature ferromagnetism (RTFM) with saturation magnetization (M{sub s}) of 3.02 × 10{sup −2} emu/g, residual magnetization (M{sub r}) of 0.68 × 10{sup −2} emu/g and coercivity (H{sub c}) of 210 Oe, which is likely attributed to the effects of the Ce{sup 3+} ions and oxygen vacancies. - Highlights: • Hexagonal CeO{sub 2} nanosheets with superexerllent RTFM are synthesized by a facile hydrothermal method. • RTFM mechanism of CeO{sub 2} nanosheets can be attributed to the influences of oxygen vacancies and Ce{sup 3+} ions. • A defect driven dissolution–recrystallization mechanism is suggested to explain the transformation from nanowires to nanosheets.

  19. Highly active and durable Ca-doped Ce-SBA-15 catalyst for biodiesel production

    International Nuclear Information System (INIS)

    In this work, Ca-doped Ce-incorporated SBA-15 (Ca/CeS) catalyst was successfully synthesized by using direct synthesis of Ce-incorporated SBA-15 followed by impregnation of CaO (calcium oxide). The maximum Si/Ce molar ratio that Ce atoms can be incorporated successfully into the mesoporous framework was found to be 5 (CeS-5). After the impregnation of 30 wt. % Ca, the obtained 30Ca/CeS-5 catalysts showed the superior catalytic performance for transesterification reaction of palm oil with methanol and also the higher catalytic activity as compared to other supported catalysts, i.e. CaO/CeO2 and CaO–CeO2/SBA-15. This can be attributed to the well-dispersion of CaO on the CeS-5 support surface. Furthermore, it was found that the leaching of Si, Ce and Ca from the catalyst into biodiesel produced was negligible (i.e. <1 ppm after 7 cycles), indicating the strong interaction between CaO and CeS-5 support. As a result, the 30Ca/CeS-5 catalyst can be reused at least 15 cycles with insignificant decrease in catalytic activity, offering the efficient CaO-based catalyst for biodiesel production. - Highlights: • Mesoporous Ca-based catalyst was successfully developed for biodiesel production. • Catalyst exhibited high activity towards transesterification (FAME yield > 98%). • Catalyst can be effectively re-used at least 15 cycles. • Extremely low catalyst contaminant (<1 ppm) was presented

  20. Efeito de agentes anti-hipertensivos sobre as células estreladas durante a regeneração hepática em ratos

    Directory of Open Access Journals (Sweden)

    Ramalho Fernando S.

    2000-01-01

    Full Text Available O efeito de um inibidor da enzima conversora da angiotensina (lisinopril, de um antagonista do receptor da angiotensina II (losartan e da bradicinina na população de células estreladas (CE durante o fenômeno regenerativo hepático foi estudado. Ratos machos Wistar receberam lisinopril, losartan, bradicinina ou solução salina em volumes proporcionais, intraperitonealmente, antes e após hepatectomia parcial a 70% (HP. Cinco animais de cada grupo experimental e controle foram sacrificados sob anestesia com éter em 36 horas após a HP. A população de CE marcadas para alfa-actina de músculo liso foi estimada nas zonas periportal e pericentral das amostras hepáticas. A população de CE foi menor no grupo tratado com losartan, e maior nos grupos tratados com bradicinina e lisinopril que no grupo controle. Estes resultados sugerem que o losartan pode inibir, e a bradicinina e o lisinopril podem estimular a população de CE durante a regeneração hepática em ratos.

  1. Fumigant Antifungal Activity of Myrtaceae Essential Oils and Constituents from <em>Leptospermum petersoniiem> against Three <em>Aspergillus> Species

    Directory of Open Access Journals (Sweden)

    Il-Kwon Park

    2012-09-01

    Full Text Available Commercial plant essential oils obtained from 11 Myrtaceae plant species were tested for their fumigant antifungal activity against <em>Aspergillus ochraceusem>, <em>A. flavusem>, and <em>A. nigerem>. Essential oils extracted from<em> em>Leptospermum> <em>petersonii> at air concentrations of 56 × 10−3 mg/mL and 28 × 10−3 mg/mL completely inhibited the growth of the three <em>Aspergillus> species. However, at an air concentration of 14 × 10−3 mg/mL, inhibition rates of <em>L. petersoniiem> essential oils were reduced to 20.2% and 18.8% in the case of <em>A. flavusem> and <em>A. nigerem>, respectively. The other Myrtaceae essential oils (56 × 10−3 mg/mL only weakly inhibited the fungi or had no detectable affect. Gas chromatography-mass spectrometry analysis identified 16 compounds in <em>L. petersoniiem>> em>essential> em>oil.> em>The antifungal activity of the identified compounds was tested individually by using standard or synthesized compounds. Of these, neral and geranial inhibited growth by 100%, at an air concentration of 56 × 10−3 mg/mL, whereas the activity of citronellol was somewhat lover (80%. The other compounds exhibited only moderate or weak antifungal activity. The antifungal activities of blends of constituents identified in <em>L. petersoniiem> oil indicated that neral and geranial were the major contributors to the fumigant and antifungal activities.

  2. Mass spectrometric studies on Ce-Cd system

    International Nuclear Information System (INIS)

    Molten salt electrorefining process, which is a pyrochemical reprocessing method, is ideally suited for reprocessing of metallic fuels. Separation of fuel material and fission products is carried out by electrorefining of spent fuel by using solid mandrel and liquid cadmium as cathodes for the electrodeposition of uranium and transuranium elements, respectively. Due to the standard electrode potentials of rare earths being close to that of transuranium elements, some amount of rare-earths are accompanied during the electrodeposition of Pu and minor actinides at liquid cadmium cathode. Therefore the investigation of thermodynamic properties of rare earth-cadmium system is essential. As part of this, vaporization studies on Ce-Cd system with the initial composition of 63.3 at % Cd (corresponding to Cd2Ce+CdCe phase region) has been investigated by Knudsen effusion mass spectrometry. This paper reports the preliminary studies carried out on this system. High purity cadmium (99.99%, M/s. Johnson Matthey Chemical Ltd, England) and cerium (99.8%, M/s. Alfa Aesar) were used for the preparation. The sample was prepared by isopiestic method by equilibrating Cd vapours over the Ce samples in a vacuum sealed quartz set up kept in a gradient furnace. The quartz set up was subsequently quenched and opened inside an argon atmosphere glove box to retrieve the sample. The phase characterization was carried out by XRD. A VG Micromass 30 BK mass spectrometer was employed for the vaporisation studies. The sample was taken in an alumina Knudsen cell (Sample loading carried out inside an argon atmosphere glovebox) and this was placed inside a molybdenum outer cup and a tungsten lid. The cell was heated by electron bombardment and the vapour effusing from Knudsen cell was ionized by electron impact, the ions produced were mass analysed by a 90° sector magnetic analyser and detected by a secondary electron multiplier. Cd+ was the ion detected in the mass spectra of the equilibrium

  3. Kantavien teräsrakenteiden CE-merkintä

    OpenAIRE

    Rissanen, Ilkka

    2016-01-01

    Tässä diplomityössä käsitellään pienelle kotimaiselle konepajalle tehtyä kehityshanketta. Työn taustalla on Euroopan unionin talousalueella 1.7.2013 voimaan astunut asetus. Asetuksessa vaaditaan, että rakennustuotteilla, joita markkinoidaan Euroopan unionin talousalueella ja, joita koskevat yhtenäistetyt Euroopan unionin tuotedirektiivit täytyy olla varustettuna CE-merkinnällä. Teräsrakenteille asetus astui lopullisesti voimaan 1.7.2014. Työn tavoitteena oli kehittää kohdeyrityksen teräs...

  4. Projected shell model study of neutron-deficient 122Ce

    Indian Academy of Sciences (India)

    Rani Devi; B D Sehgal; S K Khosa

    2006-09-01

    The observed excited states of 122Ce nucleus have been studied in the frame-work of projected shell model (PSM). The yrast band has been studied up to spin 26 ħ. The first band crossing has been predicted above a rotational frequency of 0.4 MeV/ħ that corresponds to first backbending. The calculation reproduces the experimentally observed ground state band up to spin 14ħ. The electromagnetic quantities, transition quadrupole moments and -factors are predicted and there is a need to measure these quantities experimentally.

  5. Thermal expansion of Al3Ce at very low temperatures

    International Nuclear Information System (INIS)

    Below 1 K the thermal expansion coefficient α of Al3Ce is negative and linearly approaches zero at 0 K. The pressure variation of the specific heat γT deduced from the initial variation of α is very strong: 0.62 J/K2 mole kbar. These properties cannot be interpreted with a single ion Kondo effect model but can be interpreted in terms of Fermi liquid (F.L.) behavior. The magnetostriction experiments clearly show the differences between an ordinary F.L. such as 3He and the F.L. built with a lattice of magnetic ions coupled with and by itinerant electrons

  6. Programming Windows® Embedded CE 60 Developer Reference

    CERN Document Server

    Boling, Douglas

    2010-01-01

    Get the popular, practical reference to developing small footprint applications-now updated for the Windows Embedded CE 6.0 kernel. Written by an authority on embedded application development, this book focuses in on core operating concepts and the Win32 API. It delivers extensive code samples and sample projects-helping you build proficiency creating innovative Windows applications for a new generation of devices. Discover how to: Create complex applications designed for the unique requirements of embedded devicesManage virtual memory, heaps, and the stack to minimize your memory footprintC

  7. Diversity of Scarabaeinae (Coleoptera: Scarabaeidae in the Ceará Botanical Park, Caucaia - CE, Brazil = Diversidade de Scarabaeinae (Coleoptera: Scarabaeidae no Parque Botânico do Ceará, Caucaia - CE, Brasil

    Directory of Open Access Journals (Sweden)

    Maria Goretti Araújo Lima

    2013-04-01

    Full Text Available Abstract - The objective of this study was to survey and analyze richness, abundance, equitability and diversity of Scarabaeinae species in two different environments, Carnaúba Riparian Forest and in Tabuleiro Forest in Ceará Botanic Park, Caucaia - CE, Brazil. Samples were collected monthly during the period from March to November 2008. To capture the scarabs were used 48 traps Pitfall, baited with human feces, being 24 traps in each area, distributed in two parallel transects constituted by twelve traps. Were collected at the end of the survey 5382 subfamily Scarabaeinae specimens belonging to five tribes, nine gender and 11 species. In Carnaúba Riparian Forest 3175 insects were found distributed in seven species. In Tabuleiro Forest were collected 2207 specimens belonging to 10 species. Six species occurred in both areas, one only in Riparian Forest and four in Tabuleiro Forest. Uroxys sp. was the most abundant species in both areas (35.2%, followed by Sylvicanthon sp. (31.9% and Canthidium sp.2 (16.7%. The Tabuleiro Forest showed greater wealth and Carnaúba Riparian Forest greater abundance. The observed diversity broadens the information about the community of Scarabaeinae in the state of Ceará. = Resumo - Objetivou-se com o presente trabalho realizar levantamento e análise da riqueza, abundância, equitabilidade e diversidade das espécies de Scarabaeinae em dois ambientes, Mata Ciliar de Carnaúba e Mata de Tabuleiro, no Parque Botânico do Ceará, Caucaia – CE, Brasil. As coletas foram realizadas mensalmente durante o período de março a novembro de 2008. Para captura dos escarabeídeos foram utilizadas 48 armadilhas de solo tipo “Pitfall”, iscadas com fezes humanas, sendo 24 armadilhas em cada área, distribuídas em dois transectos paralelos constituídos por doze armadilhas. Foram coletados ao final do levantamento 5.382 espécimes da subfamília Scarabaeinae pertencentes a cinco tribos, nove gêneros e 11 espécies. Na

  8. Espondiloptose em atleta

    Directory of Open Access Journals (Sweden)

    Ana Paula Luppino Assad

    2014-06-01

    Full Text Available Os atletas adolescentes estão sob maior risco de lombalgia e lesões estruturais da coluna. A espondilólise é responsável pela maioria das lombalgias em jovens esportistas e raramente ocorre em adultos. Relatamos o caso de uma paciente de 13 anos, atleta de judô, que chegou a nosso serviço com quadro de cinco meses de lombalgia progressiva durante os treinos, sendo inicialmente atribuída a causas mecânicas, sem que houvesse uma investigação mais detalhada por métodos de imagem. Na admissão já apresentava deformidade lombar, postura antálgica e manobra de hiperextensão lombar em unipodálico positiva bilateralmente. Realizou-se investigação, que evidenciou espondiloptose, sendo, então, submetida a tratamento cirúrgico. Com base neste relato de caso, discutimos a abordagem diagnóstica de lombalgia em atletas jovens, uma vez que a queixa de lombalgia crônica pode ser marcador de uma lesão estrutural, a qual pode ser definitiva e trazer perda funcional irreversível.

  9. The isolation of 139Ce after production by a proton-induced nuclear reaction on praseodymium

    International Nuclear Information System (INIS)

    A method, based on anion exchange chromatography, is presented for the isolation of 139Ce after production by a proton-induced nuclear reaction on a thick praseodymium target. After bombardment the target is dissolved in nitric acid and 139Ce oxidised to the Ce(IV) oxidation state with bromic acid. 139Ce is then separated form the praseodymium by anion exchange chromatography on a Ag MP-1 resin column in a nitric acid - bromic acid mixture. 139Ce is sorbed onto the resin column and praseodymium eluted with the acid mixture. The bromic acid is washed out of the column with nitric acid and 139Ce finally eluted with dilute nitric acid containing sulphur dioxide

  10. Catalytic combustion of benzene over CuO-CeO2 mixed oxides.

    Science.gov (United States)

    Jung, Won Young; Lim, Kwon-Taek; Hong, Seong-Soo

    2014-11-01

    Catalytic combustion of benzene over CuO-CeO2 mixed oxides has been investigated. The CuO-CeO2 mixed oxides were prepared by the combustion method using malic acid as an organic fuel and characterized by XRD, XPS and TPR. For the CuO-CeO2 catalyst with a Cu/(Cu + Ce) molar ratio of more than 0.4, highly dispersed copper oxide species were shown at 2θ = 35.5 degrees and 38.8 degrees. The CuO-CeO2 catalyst prepared using 2.0 M malic acid showed the highest activity, with conversion reaching nearly 100% at 350 degrees C. In addition, the highest activity is shown on Cu0.40 (the index denotes the molar ratio Cu/(Cu + Ce)) sample and then it decreases on Cu0.5 and Cu0.7 samples. PMID:25958554

  11. Room-temperature synthesis and characterization of porous CeO{sub 2} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Chu, Dewei; Masuda, Yoshitake; Ohji, Tatsuki; Kato, Kazumi [National Institute of Advanced Industrial Science and Technology (AIST), Anagahora, Shimoshidami, Moriyama-ku, Nagoya (Japan)

    2012-01-15

    CeO{sub 2} thin films with hexagonal-shaped pores were successfully prepared by a facile electrodeposition at room temperature combined with an etching process. By using electrodeposited ZnO nanorods as a soft template, the morphology, and microstructure of the CeO{sub 2} could be controlled. TEM observation indicated that as-prepared CeO{sub 2} film is composed of nanocrystals with average size of several nanometers, while XPS analysis showed the coexistence of Ce{sup 3+} and Ce{sup 4+} in the film. The photoluminescence properties of CeO{sub 2} films were measured, which showed much higher sensitivity compared to bare substrate. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  12. Room-temperature synthesis and characterization of porous CeO2 thin films

    International Nuclear Information System (INIS)

    CeO2 thin films with hexagonal-shaped pores were successfully prepared by a facile electrodeposition at room temperature combined with an etching process. By using electrodeposited ZnO nanorods as a soft template, the morphology, and microstructure of the CeO2 could be controlled. TEM observation indicated that as-prepared CeO2 film is composed of nanocrystals with average size of several nanometers, while XPS analysis showed the coexistence of Ce3+ and Ce4+ in the film. The photoluminescence properties of CeO2 films were measured, which showed much higher sensitivity compared to bare substrate. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  13. Magnetic Compton scattering study of CeRh3B2

    International Nuclear Information System (INIS)

    The spin-polarized electron momentum distribution (magnetic Compton profile: MCP) of ferromagnetic CeRh3B2 has been measured using the magnetic Compton scattering technique at 10 K for the [112-bar 0] direction. In this compound, the orbital moment dominates the magnetization. An analysis of the MCP reveals that the Ce 4f and Ce 5d spin moments are aligned parallel with a value of -0.68 ± 0.08 and 0.41 ± 0.04μB, respectively, while Rh 4d electrons do not carry any significant spin moment. The ratio of orbital to spin moments for Ce 4f electrons, which has been determined from comparison of the present data with recent polarized neutron diffraction data, is rather smaller than that for Ce3+ ions. This result implies strong hybridization of the Ce 4f orbital with the orbitals on the surrounding ions

  14. Passivation behavior of Ce-containing hyper duplex stainless steels in sulfuric acid solution

    International Nuclear Information System (INIS)

    The passivation behavior of Ce containing hyper duplex stainless steels in sulfuric acid solution was investigated by electrochemical testing and X-ray photoelectron spectroscopy surface analysis. The addition of Ce to the alloy increased the corrosion resistance at a passive region of 0.4 VSCE. The Ce addition also improved the stability of the passive film because of the formation of inclusions containing Ce with low Cr content and an enrichment of the Cr oxide and hydroxide in the passive film. Further, Ce addition to the alloy decreased the interface between the inclusion and the metallic matrix functioning as defects in the passive film. The Cr-enriched zones formed around the Ce containing inclusion improved the corrosion resistance of the metallic matrix around the inclusions, which act as corrosion propagation sites. (author)

  15. Equiatomic cerium intermetallics CeXX' with two p elements

    Energy Technology Data Exchange (ETDEWEB)

    Poettgen, Rainer [Muenster Univ. (Germany). Inst. fuer Anorganische und Analytische Chemie; Chevalier, Bernard [Bordeaux Univ., Pessac (France). Institut de Chimie de la Matiere Condensee de Bordeaux

    2015-07-01

    The equiatomic CeXX' phases (X and X' = elements of the 3{sup rd}, 4{sup th}, or 5{sup th} main group) extend the large series of CeTX intermetallics (T = electron-rich transition metal). These phases crystallize with simple structure types, i.e. ZrNiAl, TiNiSi, CeScSi, α-ThSi{sub 2}, AlB{sub 2}, and GdSi{sub 2}. In contrast to the CeTX intermetallics one observes pronounced solid solutions for the CeXX' phases. The main influence on the magnetic ground states results from the absence of d electrons. All known CeXX' phases show exclusively trivalent cerium and antiferro- or ferromagnetic ordering at low temperatures. The crystal chemical details and some structure-property relationships are reviewed.

  16. Equiatomic cerium intermetallics CeXX' with two p elements

    International Nuclear Information System (INIS)

    The equiatomic CeXX' phases (X and X' = elements of the 3rd, 4th, or 5th main group) extend the large series of CeTX intermetallics (T = electron-rich transition metal). These phases crystallize with simple structure types, i.e. ZrNiAl, TiNiSi, CeScSi, α-ThSi2, AlB2, and GdSi2. In contrast to the CeTX intermetallics one observes pronounced solid solutions for the CeXX' phases. The main influence on the magnetic ground states results from the absence of d electrons. All known CeXX' phases show exclusively trivalent cerium and antiferro- or ferromagnetic ordering at low temperatures. The crystal chemical details and some structure-property relationships are reviewed.

  17. Ultrasound-Assisted Extraction of Syringin from the Bark of <em>Ilex em>rotunda> Thumb Using Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Hui Wang

    2012-06-01

    Full Text Available In this work, a rapid extraction method based on ultrasound-assisted extraction (UAE of syringin from the bark of <em>Ilex rotunda em>Thumb using response surface methodology (RSM is described. The syringin was analyzed and quantified by high performance liquid chromatography coupled with UV detection (HPLC-UV. The extraction solvent, extraction temperature and extraction time, the three main factors for UAE, were optimized with Box-Behnken design (BBD to obtain the highest extraction efficiency. The optimal conditions were the use of a sonication frequency of 40 kHz, 65% methanol as the solvent, an extraction time of 30 min and an extraction temperature of 40 °C. Using these optimal conditions, the experimental values agreed closely with the predicted values. The analysis of variance (ANOVA indicated a high goodness of model fit and the success of the RSM method for optimizing syringin extraction from the bark of <em>I>. em>rotunda>.

  18. Visible light induced degradation of methylene blue using CeO2/V2O5 and CeO2/CuO catalysts

    International Nuclear Information System (INIS)

    In the present study, the nanocatalysts CeO2, V2O5, CuO, CeO2/V2O5 and CeO2/CuO were synthesized by thermal decomposition method. This method is simple, fast and cost effective compared with other preparation methods. The synthesized catalysts were characterized by different techniques. The XRD and XPS results confirmed the structure and the oxidization states of the nanocomposite materials. DRS results suggested that the prepared CeO2/V2O5 and CeO2/CuO nanocomposites can generate more electrons and holes under visible light irradiation. The photocatalytic activities of prepared catalysts were evaluated using the degradation of aqueous methylene blue solution as a model compound under visible light irradiation. In addition, the nanocomposite (CeO2/V2O5 and CeO2/CuO) materials were employed to degrade the textile effluent under visible light condition. - Highlights: • The catalysts were synthesized via a facile thermal decomposition method which was simple, fast and feasible method. • Degradation of methylene blue and real effluent were carried out under visible light. • The photocatalytic activity of nanocomposite materials is higher than that of single phase material

  19. Spectral characteristics and energy transfer from Ce3+ to Tb3+ in compounds Lu1 - x - y Ce x Tb y BO3

    Science.gov (United States)

    Shmurak, S. Z.; Kedrov, V. V.; Kiselev, A. P.; Fursova, T. N.; Smyt'ko, I. M.

    2016-03-01

    The structure, IR absorption spectra, morphology, and spectral characteristics of compounds Lu1 - x - y Ce x Tb y BO3 have been investigated. It has been shown that the Tb3+ luminescence excitation spectrum of the Lu1 - x - y Ce x Tb y BO3 compounds is dominated by a broad band coinciding with the excitation band of Ce3+ ions, which clearly indicates energy transfer from the Ce3+ ions to the Tb3+ ions. The spectral position of this band depends on the structural state of the sample: in the structures of calcite and vaterite, the band has maxima at ~339 and ~367 nm, respectively. By varying the ratio between the calcite and vaterite phases in the sample, it is possible to purposefully change the Tb3+ luminescence excitation spectrum, which is important for the optimization of the spectral characteristics of Lu1 - x - y Ce x Tb y BO3 when it is used in light-emitting diode sources. An estimate has been obtained for the maximum distance between Ce3+ and Tb3+ ions, which corresponds to electronic excitation energy transfer. It has been shown that the high intensity of Tb3+ luminescence in these compounds is due to the high efficiency of electronic excitation energy transfer from the Ce3+ ions to the Tb3+ ions as a result of the dipole-dipole interaction.

  20. Synthesis and Characterization of Ce-Doped Y3Al5O12 (YAG:Ce Nanopowders Used for Solid-State Lighting

    Directory of Open Access Journals (Sweden)

    Do Ngoc Chung

    2014-01-01

    Full Text Available Nano-Ce-doped Y3Al5O12 (YAG:Ce powders were synthesized by using a sol-gel low temperature combustion method, followed by thermal annealing. The annealing temperature for enriching nanoparticles was optimized and found to be 1000°C. The process for enriching uniform nanoparticles of YAG:Ce powder was carried out by using the nanosteam technique (NST. The nanoparticles obtained from this NST treatment had a size in the range of 9–20 nm. Measurements of the photoluminescence spectra of the dispersed YAG:Ce nanoparticles solutions showed a blue shift in the photoemission with a value of ca. 10 nm in the green region. WLEDs made from the blue LED chip coated with the nano-YAG:Ce + MEH-PPV composite epoxy exhibit white light with a broad band luminescent spectrum and a high color rending index (CRI. The photoluminescence spectra of the YAG:Ce nanoparticles showed a potential application of the prepared nanostructured YAG:Ce phosphor not only in energy-efficient solid-state lighting, but also in optoelectronic devices, including organic composite solar cells. In addition, it is suggested that NST can be applied for the enrichment of uniform inorganic nanoparticles.

  1. High-pressure Raman study on CeO{sub 2} nanospheres self-assembled by 5 nm CeO{sub 2} nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Bo; Liu, Bingbing; Li, Quanjun; Li, Zepeng; Yao, Mingguang; Liu, Ran; Zou, Xu; Lv, Hang; Wu, Wei; Cui, Wen; Liu, Zhaodong; Li, Dongmei; Zou, Bo; Cui, Tian; Zou, Guangtian [State Key Laboratory of Superhard Materials, Jilin University, Changchun 130012 (China)

    2011-05-15

    CeO{sub 2} undergoes a first-order phase transition from fluorite to {alpha}-PbCl{sub 2}-type structure under high pressure. To evaluate the changes in physical properties of CeO{sub 2} nanomaterials as the particle size decreasing, high-pressure Raman study under quasi-hydrostatic condition has been performed on CeO{sub 2} nanospheres self-assembled by 5 nm CeO{sub 2} nanoparticles at room temperature. Surprisingly, as the pressure elevate to 34 GPa, the CeO{sub 2} nanospheres still retain the cubic fluorite-type structure, indicating the sample is more stable than the bulk counterpart. Whereas, previous high-pressure studies show the phase transition at 22.3/26.5 GPa for 12 nm CeO{sub 2} nanoparticles, which is less stable than the bulk materials. The enhancement of phase stability might be attributed to the increase of surface energy of CeO{sub 2} nanospheres as the size of the building units decrease. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  2. Valence crossover of Ce ions in CeCu2Si2 under high pressure. Pressure dependence of the unit cell volume and the NQR frequency

    International Nuclear Information System (INIS)

    The pressure dependence of the valence of Ce ions in CeCu2Si2 has been investigated by means of X-ray powder diffraction (XRPD) and nuclear quadrupole resonance (NQR) measurements. The high-pressure XRPD measurements were carried out at 12 K for CeCu2Si2 and CeCu2Ge2. Precise measurements under smoothly-applied pressure were achieved through the selection of the gasket material of a diamond anvil cell. The jump of the unit cell volume, which was reported previously in CeCu2Ge2, was not observed within the experimental accuracy, indicating the absence of a first-order valance transition. The pressure dependence of 63Cu-NQR frequency νQ measured in CeCu2Si2 was compared with that calculated from the measured lattice parameters. The νQ's were calculated for the two cases of LaCu2Si2 and CeCu2Si2, corresponding to localized and itinerant cases for 4f electrons, respectively. The measured and calculated slopes dνQ/dP show good agreement. A small but significant deviation from the pressure-linear dependence in νQ was observed in the narrow pressure range of 3.9-4.5 GPa, indicating a valence crossover adjacent to the critical end point. (author)

  3. Study of Yb3+-Yb3+ and Yb3+-Ce3+ energy transfer in Yb,Ce:CaGd4Si3O13 (Yb,Ce:CGS) crystals

    International Nuclear Information System (INIS)

    The Yb radiative lifetime of 923 μs has been determined by the extrapolation to the zero concentration of Yb. Quenching of the Yb luminescence is observed in the Yb3+,Ce3+:CaGd4Si3O13 (Yb,Ce:CGS) crystals due to their intrinsic defects and Ce3+ ions. The main quenching mechanism is the energy migration through Yb ions to the defects with a micro-parameter CDD (Yb-Yb) = 1.0x10-38 cm6 s-1, and the Yb3+ → Ce3+ energy transfer with a micro-parameter CDA = 5.5x10-44 cm6 s-1. (author). Letter-to-the-editor

  4. Synthesis, magnetic, transport, and thermodynamic investigation of CeCo(Sb, Sn)3

    International Nuclear Information System (INIS)

    Highlights: ► Single crystals of CeCo(Sb, Sn)3 has been synthesized via the flux-growth method. ► The structure of CeCo(Sb, Sn)3 has been studied using X-ray diffraction. ► The elemental composition for CeCo(Sb, Sn)3 was determined by EDS. ► Magnetic and thermodynamic data indicate magnetic correlations exist between Ce ions. ► Crystal field levels give rise to an erroneously larger Sommerfeld coefficient (γ). - Abstract: CeCo(Sb, Sn)3 has been grown from Sn flux and characterized by single-crystal X-ray diffraction. The crystal structure of CeCo(Sb, Sn)3 adopts the LaPdSb3 structure-type and the structure is comprised of layers 2∞[CoX2] octahedra, where X = Sb and Sb, and nearly square nets of 2∞[X] which are separated by Ce atoms. CeCo(Sb, Sn)3 displays a metallic resistivity and the magnetic susceptibility data show paramagnetic behavior down to 2.25 K. Specific heat measurements reveal a phase transition at approximately 2 K, which is most likely magnetic. A Sommerfeld coefficient, γ = 140 mJ/K2 mol-CeCo(Sb, Sn)3, was obtained by fitting the heat capacity data at low temperatures for CeCo(Sb, Sn)3 and is indicative of enhanced charge carrier mass; however, the low temperature resistivity and magnetoresistance data do not support the formation of an enhanced mass state for CeCo(Sb, Sn)3. Thus, the enhanced Sommerfeld coefficient likely results from low lying crystal field levels which give rise to Schottky contributions at low temperatures rather than the formation of heavy quasiparticles. Herein, we report the crystal growth, structure, and physical properties for CeCo(Sb, Sn)3.

  5. Thermal-neutron scintillator: Ce3+ activated Rb2LiYBr6

    NARCIS (Netherlands)

    Birowosuto, M.D.; Dorenbos, P.; De Haas, J.T.M.; Van Eijk, C.W.E.; Krämer, K.W.; Güdel, H.U.

    2007-01-01

    Scintillation and luminescence characteristics of Rb2LiYBr6 doped with 0.1%, 0.5%, 1%, and 5% Ce3+ are presented. Under optical and x-ray excitation, Ce3+ doublet emission is observed at 385 and 420 nm. Rb2LiYBr6:0.5% Ce3+ shows very high thermal neutron scintillation light output of 83 000 photons/

  6. Structural and magnetic phase transitions in CeCu6 -xTx (T =Ag ,Pd )

    Science.gov (United States)

    Poudel, L.; de la Cruz, C.; Payzant, E. A.; May, A. F.; Koehler, M.; Garlea, V. O.; Taylor, A. E.; Parker, D. S.; Cao, H. B.; McGuire, M. A.; Tian, W.; Matsuda, M.; Jeen, H.; Lee, H. N.; Hong, T.; Calder, S.; Zhou, H. D.; Lumsden, M. D.; Keppens, V.; Mandrus, D.; Christianson, A. D.

    2015-12-01

    The structural and the magnetic properties of CeCu6 -xAgx (0 ≤x ≤0.85 ) and CeCu6 -xPdx (0 ≤x ≤0.4 ) have been studied using neutron diffraction, resonant ultrasound spectroscopy (RUS), x-ray diffraction measurements, and first principles calculations. The structural and magnetic phase diagrams of CeCu6 -xAgx and CeCu6 -xPdx as a function of Ag/Pd composition are reported. The end member, CeCu6, undergoes a structural phase transition from an orthorhombic (P n m a ) to a monoclinic (P 21/c ) phase at 240 K. In CeCu6 -xAgx , the structural phase transition temperature (Ts) decreases linearly with Ag concentration and extrapolates to zero at xS ≈0.1 . The structural transition in CeCu6 -xPdx remains unperturbed with Pd substitution within the range of our study. The lattice constant b slightly decreases with Ag/Pd doping, whereas a and c increase with an overall increase in the unit cell volume. Both systems, CeCu6 -xAgx and CeCu6 -xPdx , exhibit a magnetic quantum critical point (QCP), at x ≈0.2 and x ≈0.05 , respectively. Near the QCP, long range antiferromagnetic ordering takes place at an incommensurate wave vector (δ10 δ2), where δ1˜0.62 ,δ2˜0.25 ,x =0.125 for CeCu6 -xPdx and δ1˜0.64 ,δ2˜0.3 ,x =0.3 for CeCu6 -xAgx . The magnetic structure consists of an amplitude modulation of the Ce moments which are aligned along the c axis of the orthorhombic unit cell.

  7. Composição química e classes de lipídios em peixe de água doce Curimatã comum, Prochilodus cearensis Chemical composition and lipids classes of the freshwater fish "curimatã comum", Prochilodus cearensis

    OpenAIRE

    Everardo L. MAIA; OLIVEIRA Cláudia C. S. de; André P. SANTIAGO; CUNHA Francisca E. A.; HOLANDA Francisco C. A. F.; Janaína A. SOUSA

    1999-01-01

    O presente trabalho teve como objetivo obter dados quantitativos sobre as classes de lipídios presentes no filé de curimatã, Prochilodus cearensis. Os lipídios totais (LT) foram fracionados em classes de lipídios neutros (LN), gliceroglicolipídios (GL) e glicerofosfolipídios (PL) através de cromatografia em coluna aberta de sílica gel 60 (70-230 mesh). As análises foram realizadas em quatro lotes de amostras contendo cada uma três exemplares, adquiridos em feiras livres de Fortaleza-CE, nos m...

  8. Luminescence of Ce{sup 3+} in some chloroaluminates

    Energy Technology Data Exchange (ETDEWEB)

    Ingole, D.K.; Joshi, C.P. [Physics Department, Shri Ramdeobaba K.N. Engineering College, Katol Road, Nagpur 440013 (India); Moharil, S.V., E-mail: svmoharil@yahoo.co [Department of Physics, R.T.M. Nagpur University, Nagpur 440033 (India); Muthal, P.L.; Dhopte, S.M. [National Environmental Engineering Research Institute, C.S.I.R., Nagpur (India)

    2010-07-15

    Chloroaluminate systems are important due to their use in the production of aluminum and sodium metals, in electro-deposition of aluminum alloys, extraction of aromatic hydrocarbons, etc. However, no data on luminescence in these compounds are available. Low melting points and instability due to the high volatility of AlCl{sub 3} seem to be deterrents for carrying out such investigations. Synthesis and photoluminescence spectra of Ce{sup 3+} activated alkali chloroaluminates and some alkaline earth chloroaluminate phosphors are described for the first time in the present work. A simple wet chemical method is used for the preparation of the phosphor. Very intense emission was observed for LiCl.AlCl{sub 3} and NaCl.AlCl{sub 3}. For the former, the emission attributable to d-f transitions is entirely in the UVA1 (ultraviolet A1) region. The intensity is comparable to that of a commercial phosphor. Ce{sup 3+} activated emission in the alkaline earth compounds CaCl{sub 2}.AlCl{sub 3} and MgCl{sub 2}.2AlCl{sub 3} was relatively much weaker.

  9. Genome Mining in Sorangium cellulosum So ce56

    Science.gov (United States)

    Ewen, Kerstin Maria; Hannemann, Frank; Khatri, Yogan; Perlova, Olena; Kappl, Reinhard; Krug, Daniel; Hüttermann, Jürgen; Müller, Rolf; Bernhardt, Rita

    2009-01-01

    Myxobacteria, especially members of the genus Sorangium, are known for their biotechnological potential as producers of pharmaceutically valuable secondary metabolites. The biosynthesis of several of those myxobacterial compounds includes cytochrome P450 activity. Although class I cytochrome P450 enzymes occur wide-spread in bacteria and rely on ferredoxins and ferredoxin reductases as essential electron mediators, the study of these proteins is often neglected. Therefore, we decided to search in the Sorangium cellulosum So ce56 genome for putative interaction partners of cytochromes P450. In this work we report the investigation of eight myxobacterial ferredoxins and two ferredoxin reductases with respect to their activity in cytochrome P450 systems. Intriguingly, we found not only one, but two ferredoxins whose ability to sustain an endogenous So ce56 cytochrome P450 was demonstrated by CYP260A1-dependent conversion of nootkatone. Moreover, we could demonstrate that the two ferredoxins were able to receive electrons from both ferredoxin reductases. These findings indicate that S. cellulosum can alternate between different electron transport pathways to sustain cytochrome P450 activity. PMID:19696019

  10. La vérite sur ce qui nous motive

    CERN Document Server

    Pink, Daniel H

    2011-01-01

    Voici enfin la traduction française du best-seller international DRIVE ! Qu'est-ce qui nous motive vraiment ? Dans quels cas sommes-nous les plus performants et les plus enthousiastes ? La plupart d'entre nous sommes persuadés que les récompenses (salaire, primes...) sont notre meilleure motivation. La logique de la carotte et du bâton finalement... Et si nous faisions fausse route ? En s'appuyant sur quatre décennies d'études scientifiques et psychologiques sur la motivation humaine, Pink démontre que les entreprises dirigent très mal leurs équipes avec d'énormes conséquences sur notre vie (absence d'ambition, lassitude, morosité). Le secret de la performance (et de la satisfaction) dans les entreprises, l'enseignement ou dans notre vie personnelle , c'est le besoin profondément humain de diriger sa propre vie, d'apprendre, de créer de nouvelles choses et de s'améliorer. Dans ce livre, Pink examine les 3 éléments de la motivation, l'autonomie, la maîtrise et le besoin de donner un sens ...

  11. CE-4 Mission and Future Journey to Lunar

    Science.gov (United States)

    Zou, Yongliao; Wang, Qin; Liu, Xiaoqun

    2016-07-01

    Chang'E-4 mission, being undertaken by phase two of China Lunar Exploration Program, represents China's first attempt to explore farside of lunar surface. Its probe includes a lander, a rover and a telecommunication relay which is scheduled to launch in around 2018. The scientific objectives of CE-4 mission will be implemented to investigate the lunar regional geological characteristics of landing and roving area, and also will make the first radio-astronomy measurements from the most radio-quiet region of near-earth space. The rover will opreate for at least 3 months, the lander for half a year, and the relay for no less than 3 years. Its scinetific instruments includes Cameras, infrared imaging spectrometer, Penetrating Radar onboard the rover in which is the same as the paylads on board the CE-3 rover, and a Dust-analyzer, a Temperature-instrument and a Wide Band Low Frequency Digital Radio Astronomical Station will be installed on board the lander. Our scientific goals of the future lunar exploration will aim at the lunar geology, resources and surface environments. A series of exploraion missions such as robotic exploration and non-manned lunar scientific station is proposed in this paper.

  12. The ABB-CE system 80 standard plant design

    International Nuclear Information System (INIS)

    Design standardization of nuclear power plants provides more cost certainty and safer, more reliable plant performance to electric utilities. The U.S. nuclear market recognized these benefits of standardization in the mid-1970's and embarked on a program of licensing standard plant designs. ABB Combustion Engineering Nuclear Power (ABB-CE) had long before realized the many benefits of standardization and established a design approach that maximized these benefits. Standardization, however, does not mean stagnation. The System 80 design is a modern, proven pressurized water reactor (PWR) that has evolved through a process of continuous improvement. It has been in operation at the three unit station at Palo Verde in the U.S. since 1986. Subsequent System 80 plants (eight units) are either in operation, conducting initial start-up, or are under construction in the Republic of Korea. This design offers a high degree of safety as exhibited by the low core damage frequency (CDF) and many years of safe operation. As a group, the System 80 plants have maintained a high plant availability, with an average value exceeding 80 percent since 1991. Over the last three years, the System 80 plants have an average availability exceeding the EPRI ALWR Utility Requirements Document goal of 87%. The purpose of this paper is to provide descriptions and information regarding ABB-CE's System 80 Standard Plant, which is currently implemented in South Korea, and is ideally suited and being proposed for future deployment in Asia

  13. Classe social: conceitos e esquemas operacionais em pesquisa em saude

    Directory of Open Access Journals (Sweden)

    Rita Barradas Barata

    2013-08-01

    Full Text Available Discute-se a utilização do conceito de classe em pesquisas em saúde, as diferentes abordagens sociológicas de estratificação social e de estrutura de classes, o potencial explicativo do conceito em estudos de determinação social e desigualdades em saúde, os modelos de operacionalização elaborados para uso em pesquisas sociológicas, demográficas ou de saúde e os limites e possibilidades desses modelos. Foram destacados quatro modelos de operacionalização: de Singer para estudo da distribuição de renda no Brasil, adaptado por Barros para uso em pesquisas epidemiológicas; de Bronfman & Tuirán para o censo demográfico mexicano, adaptado por Lombardi et al para pesquisas epidemiológicas; de Goldthorpe para estudos socioeconômicos ingleses, adaptado pela Sociedade Espanhola de Epidemiologia; e o modelo de Wright para pesquisa em sociologia e ciência política, também usado em inquéritos populacionais em saúde. Em conclusão, conceitualmente cada um dos modelos apresentados é coerente com a concepção teórica que os embasam, mas não há como optar por qualquer deles, descartando os demais.

  14. Iodo em alimentos consumidos em Portugal

    OpenAIRE

    Coelho, Inês; Delgado, Inês; Costa, Sofia; Castanheira, Isabel; Calhau, Maria Antónia

    2015-01-01

    O iodo é um elemento vestigial essencial na dieta humana e animal, com uma importância nutricional bem estabelecida. É indispensável para a síntese das hormonas da tiroide, tiroxina e triiodotirosina, cujo principal papel está relacionado com o crescimento e desenvolvimento dos órgãos, em particular do cérebro. A fonte natural de iodo são os alimentos. Contudo, de acordo com a OMS um terço da população mundial sofre de algum tipo de carência de iodo. A deficiência crônica de iodo pode levar a...

  15. Prima segnalazione di <em>Brachylaima fulvusem> Dujardin, 1843 (Digenea, Brachylaimidae in <em>Sorex> cfr. <em>antinorii> Bonaparte, 1848 (Insectivora, Soricidae in Italia

    Directory of Open Access Journals (Sweden)

    Juan Carlos Casanova

    2003-10-01

    Full Text Available Un?indagine parassitologica è stata condotta su esemplari di <em>Sorex> cfr. <em>antinorii> Bonaparte, 1840 (Insectivora, Soricidae catturati in Sila Grande (Valle Capra; 16.29.30; 39.21.40. Uno degli esemplari è stato trovato parassitato da Trematodi digenei rinvenuti nell?esofago e nello stomaco. I parassiti isolati sono stati fissati con liquido di Bouin, colorati con carminio acetico di Semichon, fissati in una serie di alcooli, chiarificati in xilolo e montati con Balsamo del Canada. I parassiti sono stati identificati come membri della Famiglia Brachylaimidae Joyeux & Foley (1930 appartenenti al genere <em>Brachylaima> Dujardin (1843. La morfologia generale ed i caratteri metrici hanno permesso di identificarli come <em>B. fulvusem> Dujardin, 1843 (lunghezza corpo: 2.39-2.46; larghezza corpo: 0.72-0.78; diametro trasversale ventosa orale: 212.48- 238.08x240.64-266.24; ventosa ventrale: 250.88-258.56x250.88-266.24; faringe 120.32-168.96; testicoli: 151.04-189.44x168.96-189.44; ovario: 122.88x171.52; uova: 26-30x2-17. Il range dei dati morfometrici coincide con quelli riscontrati da diversi autori negli esemplari di <em>B. fulvusem> in Europa centrale e occidentale (Jourdane, 1971; Lewis, 1969; Zarnowski,1960; Mas-Coma & Gallego, 1975. Dopo la descrizione originale, la sistematica di <em>B. fulvusem> Blanchard, 1847 non è stata mai confutata, sebbene varie specie dei generi <em>Harmostomum> Braun, 1899 e <em>Panopistus Sinitzinem>, 1931 siano state proposte come sinonimi di <em>B. fulvusem> da diversi autori. Zarnowski (1960 considera aperta la questione di identità di <em>H. (H. dujardiniem> Baer, 1928 e propone la sinonimia di <em>B. oesophageiem> Shaldibin, 1953 e <em>B. fulvusem>. Lewis (1969, al contrario, ha riconvalidato <em>B. oesophageiem> come specie, utilizzando criteri che, però, Jourdane (1971 ritiene, non idonei a differenziare le due specie. Mas-Coma & Gallego (1975, considerano <em

  16. Growth and Photoluminescence of Epitaxial CeO2 Film on Si (111) Substrate

    Institute of Scientific and Technical Information of China (English)

    GAO Fei; ZHANG Jian-Hui; QIN Fu-Guang; YAO Zhen-Yu; LIU Zhi-Kai; WANG Zhan-Guo; LIN Lan-Ying

    2001-01-01

    A CeO2 film with a thickness of about 80nm was deposited by a mass-analysed low-energy dual ion beam deposition technique on an Si(111) substrate. Reflection high-energy electron diffraction and x-ray diffraction measurements showed that the film is a single crystal. The tetravalent state of Ce in the film was confirmed by xray photoelectron spectroscopy measurements, indicating that stoichiometric CeO2 was formed. Violet/blue light emission (379.5 nm) was observed at room temperature, which may be tentatively explained by charge transitions from the 4f band to the valence band of CeO2.

  17. Chromatographic isolation of 144Ce and 144Pr from the wastes of irradiated uranium treatment

    International Nuclear Information System (INIS)

    A two-step chromatographic technique was elaborated to isolate 144Ce, 144Pr from a solution of uranium fission products in 6M HNO3. The oxidation to Ce(III) by bromate and selective adsorption of 144Ce(IV) on anion exchange column were used to concentrate and purify 144Ce. Some impurities of uranium, 95Zr, 95Nb, 106Ru remain in 144Ce solution after the first step of its isolation. The final purification is achieved by passing the 6M HNO3 solution of 144Ce(IV) through the HDEHP-coated teflon column. The decontamination factors of 144Ce from main fission products are given. 7.2 mCi of (144Ce+144Pr) are recovered from each gram of irradiated uranium trioxide with the yield greater than 99%. An improvement of known generator was carried out to elute a purer 144Pr from maternal 144Ce(IV) adsorbed on the anion exchange column. (author)

  18. Study of structural and electronic transport properties of Ce-doped LaMnO3

    Indian Academy of Sciences (India)

    Shahid Husain; R J Choudhary; Ravi Kumar; S I Patil; J P Srivastava

    2002-05-01

    The structural and electronic transport properties of La1-CeMnO3 (=0.0-1.0) have been studied. All the samples exhibit orthorhombic crystal symmetry and the unit cell volume decreases with Ce doping. They also make a metal–insulator transition (MIT) and transition temperature increases with increase in Ce concentration up to 50% doping. The system La0.5Ce0.5MnO3 also exhibits MIT instead of charge-ordered state as observed in the hole doped systems of the same composition.

  19. Experimental investigation and thermodynamic calculation of the Zn–Fe–Ce system

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Longfei; Wu, Changjun [Jiangsu Key Laboratory of Materials Surface Science and Technology, Changzhou University, Jiangsu 213164 (China); Jiangsu Collaborative Innovation Center of Photovolatic Science and Engineering, Changzhou University, Jiangsu 213164 (China); Wang, Jianhua, E-mail: wangjh@cczu.edu.cn [Jiangsu Key Laboratory of Materials Surface Science and Technology, Changzhou University, Jiangsu 213164 (China); Jiangsu Collaborative Innovation Center of Photovolatic Science and Engineering, Changzhou University, Jiangsu 213164 (China); Liu, Ya; Tu, Hao; Su, Xuping [Jiangsu Key Laboratory of Materials Surface Science and Technology, Changzhou University, Jiangsu 213164 (China); Jiangsu Collaborative Innovation Center of Photovolatic Science and Engineering, Changzhou University, Jiangsu 213164 (China)

    2015-11-05

    The 450 °C and 600 °C isothermal sections of the Zn–Fe–Ce system were investigated using equilibrated alloys and diffusion couples. The samples were analyzed by Scanning Electron Microscopy equipped with Energy Dispersive X-ray Spectrometer analysis and X-ray power diffraction. 15 and 13 three-phase regions were identified to exist at 450 °C and 600 °C, respectively. No ternary compound was found. Ce can not dissolve into all the Zn–Fe binary compounds and the solubilities of Fe in all the Zn–Ce binary phases were limited. All the Zn–Fe compounds can equilibrate with CeZn{sub 11} and all the Ce–Zn compounds (except CeZn) can equilibrate with α-Fe. Furthermore, thermodynamic extrapolation of the Zn–Fe–Ce system was carried out and showed good agreement well with detected phase relationships. - Highlights: • 450 °C and 600 °C sections of the Zn–Fe–Ce system were constructed. • No ternary compound exists. • Ce can not dissolve into all the Zn–Fe compounds. • All the Fe–Zn compounds can equilibrate with CeZn{sub 11}. • Thermodynamic extrapolation results agree with experimental data.

  20. Oxygen storage and catalytic NO removal promoted by CeO2-containing mixed oxides

    International Nuclear Information System (INIS)

    CeO2-ZrO2 mixed oxides show improved redox properties as compared to CeO2 which makes them important innovative materials for three-way catalysts. The origin of this effect and the structural/redox correlation are discussed. The influence of the improved redox capacities on the reduction of NO by CO catalyzed by Rh/CeO2-ZrO2 catalysts is reported and evidence for an active role of the CeO2-ZrO2 support in NO activation is presented. (orig.)

  1. Selective CO oxidation in hydrogen-rich gas over CuO/CeO2 catalysts

    International Nuclear Information System (INIS)

    A series of CuO/CeO2 catalysts with different Cu-Ce compositions were synthesized by co-precipitation method and characterized by X-ray diffraction, H2-TPR, CO-TPD, SEM and X-ray photoelectron spectroscopy (XPS) techniques. The effects of Cu-Ce composition and water vapor on the catalytic properties for the selective CO oxidation in the hydrogen-rich gas were investigated. The results indicated that CuO (10%)/CeO2 catalyst remained the maximum CO conversion and selectivity at 140 and 160 deg. C, while the performance of CuO/CeO2 catalysts deteriorated with the CuO molar ratio further increased. The interfacial CuO and CeO2 interaction and synergistic effect enhanced the redox properties of CuO/CeO2 catalyst and the highly dispersed copper species were proposed as the active sites for the selective CO oxidation. The blockage of catalytic active sites by absorbed water and the formation of CO-H2O surface complexes reduced the activity of CuO (10%)/CeO2 catalyst. The decreasing of surface lattice oxygen and absorbed oxygen species and the agglomeration of copper particles were the plausible interpretations for the deactivation of CuO (10%)/CeO2 catalyst

  2. New high temperature modification of CeTiGe: structural characterization and physical properties.

    Science.gov (United States)

    Chevalier, B; Hermes, W; Gaudin, E; Pöttgen, R

    2010-04-14

    The new high temperature form (HT) of the ternary germanide CeTiGe was prepared by annealing at 1373 K. The investigation of HT-CeTiGe by x-ray powder diffraction shows that the compound crystallizes in the tetragonal CeScSi type structure (space group I4/mmm; a=414.95(2) and c=1590.85(10) pm as unit cell parameters). Electrical resistivity, thermoelectric power, magnetization and specific heat measurements performed down to 2 K on HT-CeTiGe reveal a non-magnetic strongly correlated electron system; the specific heat divided by temperature attains a value of 0.635 J mol(-1) K(-2) at 2 K. The comparison of the physical properties of the two crystallographic modifications of CeTiGe suggests a decrease of the hybridization J(cf) between 4f(Ce) and conduction electrons in the sequence LT-CeTiGe [Formula: see text]-CeTiGe (CeScSi type). PMID:21389537

  3. Effect of Ce addition on the mechanical and electrochemical properties of a lithium battery shell alloy

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Junchao [School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Ding, Dongyan, E-mail: dyding@sjtu.edu.cn [School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Xu, Xinglong [School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Gao, Yongjin; Chen, Guozhen; Chen, Weigao; You, Xiaohua [Huafon NLM Al Co., Ltd, Shanghai 201506 (China); Huang, Yuanwei; Tang, Jinsong [Shanghai Huafon Materials Technology Institute, Shanghai 201203 (China)

    2014-12-25

    Highlights: • Fabrication of Ce-free and Ce-containing Al–Cu–Mn–Fe–Mg alloy. • TEM, tensile and electrochemical characterization of the alloys. • Ce element greatly affects the precipitation of the alloy. • Ce element had great impact on the tensile strength and corrosion potential of the alloys. - Abstract: Due to severe application environment lithium battery shell of new-energy automotives requires increasing demands for using high performance aluminum alloys. In the present work, effect of Ce addition on the microstructure, tensile and electrochemical properties of an Al–Cu–Mn–Mg–Fe alloy were investigated through using X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), tensile tests and electrochemical tests. The experimental results indicated that the addition of Ce element could promote the precipitation of second phases. With addition of 0.36% Ce, high melting point Al{sub 8}Cu{sub 4}Ce phase and many Al{sub 20}Cu{sub 2}Mn{sub 3} particles could be found. In addition, the precipitation of conventionally dominant phase of Al{sub 2}Cu could be suppressed in alloy. The Ce addition was found to result in enhanced tensile strength and improved corrosion resistance.

  4. Glutathione replenishing potential of CeO₂ nanoparticles in human breast and fibrosarcoma cells.

    Science.gov (United States)

    Akhtar, Mohd Javed; Ahamed, Maqusood; Alhadlaq, Hisham A; Khan, M A Majeed; Alrokayan, Salman A

    2015-09-01

    Recently, cerium oxide nanoparticles (CeO2 NPs) has been reported for multi-enzyme mimetic activities like that of superoxide dismutase and catalase. Here, we report glutathione (GSH) replenishing response by CeO2 NPs in human breast (MCF-7) and fibrosarcoma (HT-1080) cells. CeO2 NPs were found to be mostly cuboidal in shape with average diameter of 25 nm. Effects on cell viability, reactive oxygen species (ROS) generation, and mitochondrial outer membrane potential (MOMP) suggested CeO2 NPs to be reasonably non-cytotoxic. Data on membrane damage and lipid peroxidation correlated well with the cell viability results suggesting NPs of CeO2 to be biocompatible. Interestingly, CeO2 NPs significantly increased intracellular GSH in cells challenged with oxidants. Replenishment of depleted GSH in oxidatively challenged cells was comparable with the GSH restoring potential of known antioxidant N-acetyl cysteine (NAC), a precursor of GSH. Like NAC, CeO2 NPs significantly replenished depleted GSH in both cell types challenged with hydrogen peroxide (H2O2) and zinc oxide (ZnO) NPs. Moreover, CeO2 NPs treated cells were significantly protected from cytotoxicity caused by H2O2 and ZnO NPs. Our findings, therefore, suggest CeO2 NPs as a potential antioxidant rather than a toxic material. PMID:25965428

  5. Electronic structure of the heavy fermion superconductor Ce2PdIn8: Experiment and calculations

    International Nuclear Information System (INIS)

    The electronic structure of a heavy-fermion superconductor Ce2PdIn8 was investigated by means of X-ray photoelectron spectroscopy (XPS) and ab initio density functional band structure calculations. The Ce 3d core-level XPS spectra point to stable trivalent configuration of Ce atoms that is also reproduced in the band structure calculations within the generalized gradient approximation GGA+U approach. Analysis of the 3d9f2 weight in the 3d XPS spectra within the Gunnarsson-Schönhammer model suggests that the onsite hybridization energy between Ce 4f and the conduction band states, Δfs, is ∼120 meV, which is about 30 meV larger than Δfs in isostructural Ce2TIn8 compounds with T = Co, Rh, and Ir. Taking into account a Coulomb repulsion U on both the Ce 4f and Pd 4d states in electronic band structure calculations, a satisfactory agreement was found between the calculated density of states (DOS) and the measured valence band XPS spectra. - Highlights: • XPS data validated strong electronic correlations in superconducting Ce2PdIn8. • DFT calculations reproduced XPS spectra measured for Ce2PdIn8. • Crucial role of Pd d electrons in the HF behavior of Ce2PdIn8 was established

  6. Fragility and glass forming ability of Al-Ni-Ce alloy melts

    Institute of Scientific and Technical Information of China (English)

    赵岩; 边秀房; 孙民华; 张均艳

    2004-01-01

    The fragility of Al-Ni-Ce alloy melts with three kinds of different compositions, Al85Ni10Ce5,Al85Ni8Ce7, Al85Ni5Ce10(mole fraction, %), was studied using oscillating-vessel viscometer and differential scanning calorimetry. Their fragility parameters obtained from experiments and theoretic calculation are:238,228 and 335 respectively. The results indicate that these three kinds of Al-Ni-Ce alloy melts are very fragile liquids, which kinetically show strong non-Arrhenius behaviour in the Angell plot, so they have poor glass forming ability (GFA).The alloy melt Al85Ni5Ce10 has the largest fragility parameter among the three alloy melts. In the preparation of rapidly quenched amorphous ribbons, Al85Ni10Ce5 and Al85Ni8Ce7 can gain amorphous ribbons when the rotate speed of the roller reaches 800 r/min, while for Al85Ni5Ce10 it must exceed 1 000 r/min.

  7. Effects of CeF3 on properties of self-shielded flux cored wire

    Institute of Scientific and Technical Information of China (English)

    Yu Ping; Tian Zhiling; Pan Chuan; Xue Jin

    2006-01-01

    Effects of CeF3 on properties of self-shielded flux cored wire including welding process, inclusions in weld metal and mechanical properties are systematically studied. Welding smoke and spatter are reduced with the addition of CeF3. The main non-metallic inclusions in weld metal are AlN and Al2 O3. CeF3 can refine non-metallic inclusions and reduce the amount of large size inclusions, which is attributed to the inclusion floating behavior during the solidification of weld metal. The low temperature impact toughness is improved by adding suitable amount of CeF3 in the flux.

  8. Effect of Ce addition on the mechanical and electrochemical properties of a lithium battery shell alloy

    International Nuclear Information System (INIS)

    Highlights: • Fabrication of Ce-free and Ce-containing Al–Cu–Mn–Fe–Mg alloy. • TEM, tensile and electrochemical characterization of the alloys. • Ce element greatly affects the precipitation of the alloy. • Ce element had great impact on the tensile strength and corrosion potential of the alloys. - Abstract: Due to severe application environment lithium battery shell of new-energy automotives requires increasing demands for using high performance aluminum alloys. In the present work, effect of Ce addition on the microstructure, tensile and electrochemical properties of an Al–Cu–Mn–Mg–Fe alloy were investigated through using X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), tensile tests and electrochemical tests. The experimental results indicated that the addition of Ce element could promote the precipitation of second phases. With addition of 0.36% Ce, high melting point Al8Cu4Ce phase and many Al20Cu2Mn3 particles could be found. In addition, the precipitation of conventionally dominant phase of Al2Cu could be suppressed in alloy. The Ce addition was found to result in enhanced tensile strength and improved corrosion resistance

  9. Microstructure and properties of a Mo-CeO2 heated cathode material

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jiuxing; WAN Xiaofeng; LI Xiangbo; ZHOU Wenyuan; ZHOU Meiling

    2004-01-01

    The microstructure, mechanical properties, and electron-emission properties of a newly developed heated cath ode material Mo-CeO2 with 4.0% (mass fraction) of CeO2 were investigated. It is shown that the Mo-CeO2 cathode material possesses high tensile strength and good room-temperature ductility. After carbonized, the Mo-CeO2 cathode material has a higher zero field emission current density and a lower work function compared with the W-ThO2 cathode material.

  10. Role of electron transfer in Ce3+ sensitized Yb3+ luminescence in borate glass

    International Nuclear Information System (INIS)

    In a Ce3+-Yb3+ system, two mechanisms are proposed so far namely, the quantum cutting mechanism and the electron transfer mechanism explaining Yb3+ infrared luminescence under Ce3+ excitation. Among them, the quantum cutting mechanism, where one Ce3+ photon (ultraviolet/blue) gives rise to two Yb3+ photons (near infrared) is widely sought for because of its huge potential in enhancing the solar cell efficiency. In present study on Ce3+-Yb3+ codoped borate glasses, Ce3+ sensitized Yb3+ luminescence at ∼1 μm have been observed on Ce3+ 5d state excitation. However, the intensity of sensitized Yb3+ luminescence is found to be very weak compared to the strong quenching occurred in Ce3+ luminescence in Yb3+ codoped glasses. Moreover, the absolute luminescence quantum yield also showed a decreasing trend with Yb3+ codoping in the glasses. The overall behavior of the luminescence properties and the quantum yield is strongly contradicting with the quantum cutting phenomenon. The results are attributed to the energetically favorable electron transfer interactions followed by Ce3+-Yb3+ ⇌ Ce4+-Yb2+ inter-valence charge transfer and successfully explained using the absolute electron binding energies of dopant ions in the studied borate glass. Finally, an attempt has been presented to generalize the electron transfer mechanism among opposite oxidation/reduction property dopant ions using the vacuum referred electron binding energy (VRBE) scheme for lanthanide series

  11. Effect of Cerium on Chemical Short-Range Order of Al-Fe-Ce Amorphous Alloy

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The chemical short-range order of Al-Fe-Ce amorphous alloy was studied by means of X-ray diffraction(XRD) and differential scanning calorimetry(DSC). It is found that the prepeak position in X-ray diffraction intensity curve shifts to higher angles as the content of Fe increases, but it shifts to smaller angles as the content of Ce increases. The crystallization character of the amorphous alloy changes with the variation of the content of Fe and Ce. Ce can improve the interaction between atoms and the capacity of compound formation, so it is favorable to Al-based glass formability.

  12. Study on the intermetallic phases in the Mg-Ce system

    International Nuclear Information System (INIS)

    Mg-Ce diffusion couple annealed at 400 oC was investigated via electron probe microanalysis (EPMA), and scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS). The results validated the compositions of the intermetallic phases experimentally determined by Zhang et al. on the Mg-rich side of the binary phase diagram and refined the phase diagram suggested by Zhang et al. for the composition range of 38-70 wt% Ce. A revised equilibrium phase diagram was proposed for the Mg-Ce system up to 50 at% Ce.

  13. Luminescence of Ce3+ doped LaPO4 nanophosphors upon Ce3+ 4f-5d and band-to-band excitation

    International Nuclear Information System (INIS)

    Luminescence spectral-kinetic studies have been performed for pure and Ce-doped LaPO4 micro- and nanosized phosphates using synchrotron radiation for the excitation within 5-20 eV energy range at T=8-300 K. Mechanisms for the excitation of Ce3+ 5d-4f emission as well as the quenching processes are discussed. The influence of surface defects has been considered to modify considerably the luminescent properties of nanosized phosphors upon the excitation in the energy range of Ce3+ 4f-5d transitions and LaPO4 host absorption

  14. The role of Ce reduction in the segregation of metastable phases in the ZrO2–CeO2 system

    OpenAIRE

    Sanjuán, M. L.; Oliete, Patricia B.; Várez, A.; Sanz Lázaro, Jesús

    2012-01-01

    The complexity of the ZrO2–CeO2 phase diagram arises from several factors: the low solubility of each compound into the other one, the slow kinetics of cation diffusion, the occurrence of Ce reduction at high temperatures, and the existence of several metastable phases whose appearance and evolution depend on synthesis method and thermal history of the sample. Identification of phase content is moreover complicated because the X-ray diffractograms of some ZrO2–CeO2 phases are very close or ev...

  15. Estudo comparativo entre contextos de brincadeiras em instituição de acolhimento infantil = Comparative study of contexts of play in the host institution for children = Estudio de comparación entre contextos de juegos en institución de acogida infantil

    OpenAIRE

    Oliveira, Luísa Sousa Monteiro

    2015-01-01

    O objetivo deste trabalho foi descrever e comparar as brincadeiras ocorridas em contextos: estruturado (CE) e semiestruturado (CSE) em uma instituição de acolhimento infantil. Participaram 10 crianças de cinco a seis anos, com tempo de acolhimento que variou de um a 12 meses. As sessões observacionais foram realizadas no CE (brinquedoteca) e no CSE (barracão, playground e piscina). Realizaram-se 117 registros de cinco minutos, totalizando 585 minutos de observação. Os resultados mostraram que...

  16. The EM Earthquake Precursor

    Science.gov (United States)

    Jones, K. B., II; Saxton, P. T.

    2013-12-01

    Many attempts have been made to determine a sound forecasting method regarding earthquakes and warn the public in turn. Presently, the animal kingdom leads the precursor list alluding to a transmission related source. By applying the animal-based model to an electromagnetic (EM) wave model, various hypotheses were formed, but the most interesting one required the use of a magnetometer with a differing design and geometry. To date, numerous, high-end magnetometers have been in use in close proximity to fault zones for potential earthquake forecasting; however, something is still amiss. The problem still resides with what exactly is forecastable and the investigating direction of EM. After the 1989 Loma Prieta Earthquake, American earthquake investigators predetermined magnetometer use and a minimum earthquake magnitude necessary for EM detection. This action was set in motion, due to the extensive damage incurred and public outrage concerning earthquake forecasting; however, the magnetometers employed, grounded or buried, are completely subject to static and electric fields and have yet to correlate to an identifiable precursor. Secondly, there is neither a networked array for finding any epicentral locations, nor have there been any attempts to find even one. This methodology needs dismissal, because it is overly complicated, subject to continuous change, and provides no response time. As for the minimum magnitude threshold, which was set at M5, this is simply higher than what modern technological advances have gained. Detection can now be achieved at approximately M1, which greatly improves forecasting chances. A propagating precursor has now been detected in both the field and laboratory. Field antenna testing conducted outside the NE Texas town of Timpson in February, 2013, detected three strong EM sources along with numerous weaker signals. The antenna had mobility, and observations were noted for recurrence, duration, and frequency response. Next, two

  17. <em>Bacillus anthracisem> Factors for Phagosomal Escape

    Directory of Open Access Journals (Sweden)

    Irene Zornetta

    2012-07-01

    Full Text Available The mechanism of phagosome escape by intracellular pathogens is an important step in the infectious cycle. During the establishment of anthrax, <em>Bacillus anthracisem> undergoes a transient intracellular phase in which spores are engulfed by local phagocytes. Spores germinate inside phagosomes and grow to vegetative bacilli, which emerge from their resident intracellular compartments, replicate and eventually exit from the plasma membrane. During germination, <em>B. anthracisem> secretes multiple factors that can help its resistance to the phagocytes. Here the possible role of <em>B. anthracisem> toxins, phospholipases, antioxidant enzymes and capsules in the phagosomal escape and survival, is analyzed and compared with that of factors of other microbial pathogens involved in the same type of process.

  18. On subspecific taxonomy of <em>Microtus saviiem> (Rodentia, Arvicolidae

    Directory of Open Access Journals (Sweden)

    Longino Contoli

    2003-10-01

    Full Text Available Riassunto Sulla tassonomia sottospecifica di <em>Microtus saviiem> (Rodentia, Arvicolidae Viene riveduta e riassunta la situazione tassonomica sottospecifica di <em>Microtus (Terricola saviiem>, anche tramite la descrizione di due nuovi taxa: <em>Microtus (Terricola savii tolfetanusem>, dei Monti della Tolfa e <em>Microtus (Terricola savii niethammericusem>, del Gargano.

  19. Ancylostoma duodenale em estrangeiros radicados em Botucatu, SP, Brasil

    Directory of Open Access Journals (Sweden)

    Florence F.S. Kerr

    1981-06-01

    Full Text Available Utilizando-se a técnica de Harada & Mori foi efetuada verificação das espécies de Ancylostomidae prevalentes entre imigrantes europeus, asiáticos e brasileiros residentes no município de Botucatu, Estado de São Paulo, Brasil. Ancylostoma duodenale foi encontrado em 8,5% dos imigrantes asiáticos e Necator americanus em 3,5% dos europeus e em 18% dos brasileiros examinados.

  20. How <em>Varroa> Parasitism Affects the Immunological and Nutritional Status of the Honey Bee, <em>Apis melliferaem>

    Directory of Open Access Journals (Sweden)

    Katherine A. Aronstein

    2012-06-01

    Full Text Available We investigated the effect of the parasitic mite <em>Varroa destructorem> on the immunological and nutritional condition of honey bees, <em>Apis melliferaem>, from the perspective of the individual bee and the colony. Pupae, newly-emerged adults and foraging adults were sampled from honey bee colonies at one site in S. Texas, USA. <em>Varroa>‑infested bees displayed elevated titer of Deformed Wing Virus (DWV, suggestive of depressed capacity to limit viral replication. Expression of genes coding three anti-microbial peptides (<em>defensin1, abaecin, hymenoptaecinem> was either not significantly different between <em>Varroa>-infested and uninfested bees or was significantly elevated in <em>Varroa>-infested bees, varying with sampling date and bee developmental age. The effect of <em>Varroa> on nutritional indices of the bees was complex, with protein, triglyceride, glycogen and sugar levels strongly influenced by life-stage of the bee and individual colony. Protein content was depressed and free amino acid content elevated in <em>Varroa>-infested pupae, suggesting that protein synthesis, and consequently growth, may be limited in these insects. No simple relationship between the values of nutritional and immune-related indices was observed, and colony-scale effects were indicated by the reduced weight of pupae in colonies with high <em>Varroa> abundance, irrespective of whether the individual pupa bore <em>Varroa>.

  1. Trabalho em equipa

    OpenAIRE

    Antunes, Andreia Sofia Duarte

    2016-01-01

    O presente relatório de estágio tem como tema principal o trabalho em equipa. Aborda com mais pormenor o subtema dos momentos de reflexão na equipa pedagógica. Ao longo do estudo são vários os conceitos abordados e a interligação entre os mesmos. Pretendo dar a conhecer a temática em questão e conceções que lhe estão naturalmente associadas. Sendo um estudo investigativo são abordados os métodos utilizados ao longo de toda a investigação. Com este relatório pretende-se alcançar qual ...

  2. Novel nanostructured CeO2 as efficient catalyst for energy and environmental applications

    Indian Academy of Sciences (India)

    Sumanta Kumar Meher; G Ranga Rao

    2014-03-01

    We report here versatile methods to engineer the microstructure and understand the fundamental physicochemical properties of CeO2 to improve its catalytic viability for practical applications. In this context, different morphologies of CeO2 are synthesized using tailored homogeneous precipitation methods and characterized by XRD, BET, SEM and TPR methods. The shuttle-shaped CeO2 prepared under hydrothermal condition shows higher surface area and low-temperature reducibility. The 0.5 wt% Pt-impregnated shuttle-shaped CeO2 shows lower-temperature CO oxidation behaviour as compared to its bulk-like CeO2 (with 0.5 wt% Pt) counterpart, synthesized by conventional-reflux method. Further, nanorod morphology of CeO2 prepared with Cl−as counter ion shows lower-temperature oxidation of soot as compared to the mesoflower morphology of CeO2, prepared with NO$^{−}_{3}$ as counter ion in the reaction medium. Further, linear sweep voltammetry, chronopotentiometry and CO-stripping voltammetry studies are performed to evaluate the promoting activity of CeO2 to Pt/C for ethanol electro-oxidation reaction in acidic media. Results show that CeO2 provides active triple-phase-interfacial sites for suitable adsorption of OH species which effectively oxidize the COads on Pt/C. The results presented here are significant in the context of understanding the physicochemical fine prints of CeO2 and CeO2 based hetero-nanocomposites for their suitability to important catalytic and energy-related applications.

  3. Photocatalytic degradation mechanisms of CeO2/Tb2O3 nanotubes

    International Nuclear Information System (INIS)

    Highlights: • CeO2/Tb2O3 nanotubes have been synthesized using the surfactant free co-precipitation method. • HRTEM images, XPS spectra, and EDAX profiles showed that the as-synthesized samples were CeO2/Tb2O3 nanotubes. • Photocatalytic activity of the synthesized catalysts was evaluated by degrading Methylene blue under visible light irradiation. • Estimated rate constants for the CeO2 nanoparticles and the CeO2/Tb2O3 nanotubes were 0.0134 and 0.0317 min−1, respectively. • Photodegradation efficiency of CeO2/Tb2O3 nanotubes was 93% after 75 min. - Abstract: CeO2/Tb2O3 nanotubes (NTs) have been synthesized using the surfactant free co-precipitation method. High resolution transmission electron microscopy (HRTEM) images, X-ray spectroscopy (XPS) spectra, and energy dispersive X-ray (EDAX) profiles showed that the as-synthesized samples were CeO2/Tb2O3 NTs. The photocatalytic activity of the synthesized catalysts was evaluated by degrading Methylene blue (MB) under visible light irradiation. The fitting of the absorbance maximum as a function of time showed that the photodegradation of the MB followed pseudo-first-order reaction kinetics. The estimated rate constants for the CeO2 NPs and the CeO2/Tb2O3 NTs were found to be 0.0134 and 0.0317 min−1, respectively. The photodegradation efficiency of CeO2/Tb2O3 nanotubes was 93% after 75 min, which was found to be higher than those of CeO2 NPs (66%)

  4. Vulnerabilidades presentes no percurso vivenciado pelos pacientes com HIV/AIDS em falha terapêutica

    Directory of Open Access Journals (Sweden)

    Petra Kelly Rabelo de Sousa

    2013-04-01

    Full Text Available Um grande avanço no tratamento da AIDS deu-se com o surgimento da terapia antiretroviral. Entretanto, diversas vulnerabilidades podem estar presentes no percurso vivenciado pelos pacientes durante o tratamento. Objetivou-se analisar as vulnerabilidades dos pacientes com HIV/AIDS em falha terapêutica. Estudo qualitativo realizado com sete usuários com AIDS considerados em falha terapêutica, em uma Unidade de Serviço Ambulatorial Especializado em HIV/AIDS, em Fortaleza-CE. Para interpretação dos dados, utilizou-se uma técnica de análise de conteúdo. Nos discursos, percebeu-se que os depoentes enfrentavam conflitos na família e, no ambiente de trabalho, dificuldades de relacionamento com as pessoas e estigma. Observou-se que os pacientes haviam vivenciado diversas situações que os tornaram mais suscetíveis à infecção por HIV e ao adoecimento.

  5. CeO2空心微球的制备与表征%Preparation and Characterization of CeO2 Hollow Spheres

    Institute of Scientific and Technical Information of China (English)

    吴秀勇; 王巍; 吕伟丽; 仉丽; 朱立平

    2007-01-01

    以PSA-A乳胶粒为模板,通过硫酸高铈和尿素的水解反应得到PSA/水合CeO2的核/壳结构的复合微球,通过煅烧除去乳胶粒模板得到立方相CeO2空心微球.CeO2空心微球平均粒径为450 nm~500 nm,由11.76 nm的小粒子堆积而成.考察了Ce4+、尿素、PVP的浓度,反应温度,PSA-A乳胶粒的加入量等实验条件对包覆效果的影响,通过FT-IR、XRD、TEM、SEM对样品进行了表征.

  6. Experimental evidence for self-assembly of CeO2 particles in solution: Formation of single-crystalline porous CeO2 nanocrystals

    DEFF Research Database (Denmark)

    Tan, Hui Ru; Tan, Joyce Pei Ying; Boothroyd, Chris;

    2012-01-01

    Single-crystalline porous CeO2 nanocrystals, with sizes of ∼20 nm and pore diameters of 1-2 nm, were synthesized successfully using a hydrothermal method. Using electron tomography, we imaged the three-dimensional structure of the pores in the nanocrystals and found that the oriented aggregation of...... small CeO2 nanoparticles resulted in the growth of CeO2 nanocrystals with an irregular truncated octahedral shape and pores extending along the 〈110〉 directions. Oxygen vacancies were found on the crystal surfaces and internal walls of the pores by scanning transmission electron microscopy and electron...... energy-loss spectroscopy. The oxygen vacancies might play an important role in oxygen diffusion in the crystals and the catalytic activities of single-crystalline porous CeO 2 structures. © 2011 American Chemical Society....

  7. Growth of Ce:LiYF4 bulk single crystal with high Ce concentration by Cz method and the scintillation properties

    International Nuclear Information System (INIS)

    Ce 2% doped LiYF4 [Ce:LYF] bulk single crystal was grown by Czochralski method and the structural phase, crystallinity, optical properties and scintillation properties were investigated. Grown Ce:LYF bulk single crystal included some cracks in the initial part of crystal and meanwhile there were no visible cracks in the center and end parts. Full width of half maximum of X-ray rocking curve on the plate crystal in center part of Ce:LYF bulk single crystal was 81.4 arcsec. Alpha-ray position in the pulse-height spectra under alpha-ray irradiation was almost quarter that of Li-glass(GS20). Decay times of the crystals in center and end parts were 69.9 and 58.3 ns, respectively (copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  8. Growth of Ce:LiYF{sub 4} bulk single crystal with high Ce concentration by Cz method and the scintillation properties

    Energy Technology Data Exchange (ETDEWEB)

    Yokota, Yuui; Yamaji, Akihiro; Kurosawa, Shunsuke [Institute for Materials Research, Tohoku University, Sendai, 9808577 Miyagi (Japan); Kawaguchi, Noriaki; Fukuda, Kentaro [Tokuyama Corp., Sendai, 9893204 Miyagi (Japan); Yoshikawa, Akira [Institute for Materials Research, Tohoku University, Sendai, 9808577 Miyagi (Japan); New Industry Creation Hatchery Center (NICHe), Tohoku University, Sendai, 9893204 Miyagi (Japan)

    2012-12-15

    Ce 2% doped LiYF4 [Ce:LYF] bulk single crystal was grown by Czochralski method and the structural phase, crystallinity, optical properties and scintillation properties were investigated. Grown Ce:LYF bulk single crystal included some cracks in the initial part of crystal and meanwhile there were no visible cracks in the center and end parts. Full width of half maximum of X-ray rocking curve on the plate crystal in center part of Ce:LYF bulk single crystal was 81.4 arcsec. Alpha-ray position in the pulse-height spectra under alpha-ray irradiation was almost quarter that of Li-glass(GS20). Decay times of the crystals in center and end parts were 69.9 and 58.3 ns, respectively (copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  9. On the Ce-Mn clustering in CaF2 in which the Ce3+ → Mn2+ energy transfer occurs

    International Nuclear Information System (INIS)

    Energy transfer from Ce3+ to Mn2+ ions in a single crystal of CaF2 co-doped with cerium and manganese ions has been analysed. The spectroscopic data obtained clearly indicate that sensitized luminescence with cerium ions as sensitizers and manganese ions as activators takes place between Ce3+ - Mn2+ clusters formed in the crystalline matrix. The number of such clusters was estimated using a simple model in which both ions are treated as two-energy-level systems. Some insight into the possible nature of the Ce3+ - Mn2+ complexes as well as of the Ce3+ → Mn2+ energy transfer mechanism taking place inside them were gathered using Dexter's theory for energy transfer phenomena

  10. CeO_2-supported vanadium oxide catalysts for soot oxidation:the roles of molecular structure and nanometer effect

    Institute of Scientific and Technical Information of China (English)

    刘坚; 赵震; 徐春明; 段爱军; 姜桂元

    2010-01-01

    The nanometer CeO2 powder was prepared by the method of microwave-assisted heating hydrolysis,and the nanometer CeO2-supported or ordinary CeO2-supported vanadia catalysts with different vanadium loadings(atomic ratios:100V/Ce=0.1,1,4,10,and 20) were prepared by an incipient-wetness impregnation method.Spectroscopic techniques(XRD,FT-IR,Raman and UV-Vis DRS) were utilized to characterize the structures of VOx/CeO2 catalysts.The results showed that the structures of CeO2-supported vanadium oxide catalysts de...

  11. "Ce que le langage ne peut pas faire"

    OpenAIRE

    Ramond, Charles

    2009-01-01

    La conférence remet en cause la spécificité des "actes de parole" et de leurs échecs ("ce que le langage ne peut pas faire") par rapport aux "actes" en général et à leurs échecs. De même en effet que l'on "fait" toujours autre chose en "disant" quelque chose, on "fait" aussi toujours autre chose en "faisant" quelque chose. En face du "locutoire", il y a donc le "factif", en face de "l'illocutoire", "l'infactif", et en face du "perlocutoire", le "perfactif". La démonstration s'appuie sur l'épi...

  12. Collective magnetic response of CeO2 nanoparticles

    Science.gov (United States)

    Coey, Michael; Ackland, Karl; Venkatesan, Munuswamy; Sen, Siddhartha

    2016-07-01

    The magnetism of nanoparticles and thin films of wide-bandgap oxides that include no magnetic cations is an unsolved puzzle. Progress has been hampered by both the irreproducibility of much of the experimental data, and the lack of any generally accepted theoretical explanation. The characteristic signature is a virtually anhysteretic, temperature-independent magnetization curve that saturates in an applied field that is several orders of magnitude greater than the magnetization. It would seem as if a tiny volume fraction, temperature-independent magnetization curve and its doping and dispersion dependence, based on a length scale of 300 nm that corresponds to the wavelength of a maximum in the ultraviolet absorption spectrum of the magnetic CeO2 nanoparticles. The coherent domains occupy roughly 10% of the sample volume.

  13. Level structure and transition probabilities in 140Ce

    International Nuclear Information System (INIS)

    The interplay of collective and non-collective modes in 140Ce is studied via comparison of available data with results of the quasiparticle-phonon model (QPM). Lifetime values have been checked in the 140La decay using delayed βγ coincidences. The half-life of the Jπ 41+ level is confirmed as T1/2(2083.6 keV) 3.3 ± 0.2 ns and upper limits of 0.1-0.2 ns are estimated for other levels. Extensive calculations within the QPM are carried out including one-, two-and three-phonon components in the wavefunctions. Comparisons to other N = 82 nuclei are also made as well. (author)

  14. Anisotropic elastic properties of CeRhIn5

    International Nuclear Information System (INIS)

    The structure of the quasi-two-dimensional heavy fermion antiferromagnet CeRhIn5 has been investigated as a function of pressure up to 13 GPa using a diamond anvil cell under both hydrostatic and quasihydrostatic conditions at room (T=295 K) and low (T=10 K) temperatures. Complementary resonant ultrasound measurements were performed to obtain the complete elastic moduli. The bulk modulus (B≅78 GPa) and uniaxial compressibilities (κa=3.96x10-3 GPa-1 and κc=4.22x10-3 GPa-1) found from pressure-dependent x-ray diffraction are in good agreement with the ultrasound measurements. Unlike doping on the Rh site where Tc increases linearly with the ratio of the tetragonal lattice parameters c/a, no such correlation is observed under pressure; instead, a double-peaked structure with a local minimum around 4-5 GPa is observed at both room and low temperatures

  15. Mani (216–276 CE and Ethiopian Enoch

    Directory of Open Access Journals (Sweden)

    Pieter M. Venter

    2014-02-01

    Full Text Available Mani (216–276 CE lived in a world where many ideas contributed to his unique theology. In the scriptural legacy of Mani seven of his books show influence of Ethiopian Enoch. These books are identified in this article and the use of Enochic material in those books is discussed. The Manichaean myth is briefly discussed and used to propose that Enochic influence can mainly be found in the way First Enoch depicted characters and presented the cosmos. Mani adopted his ideas mainly from the Book of the Watchers (1 En 1–36, the Book of Parables (1 En 37–71 and the Astronomical Book of Enoch (72–82 where evil beings and cursed places are depicted.

  16. Cyril Lemieux, Le devoir et la grâce

    OpenAIRE

    Hourlier, Fabrice

    2011-01-01

    Avec Le devoir et la grâce, Cyril Lemieux souhaite faire passer le concept de « grammaire » du côté des sciences sociales en écho à l'historien Fernand Braudel qui parlait de « grammaire des civilisations ». Cette notion serait en effet susceptible d'accroître notre faculté à comprendre des actions humaines qui se déroulent dans des formes de vie très différentes des nôtres. La grammaire étant entendue comme l'ensemble des règles à suivre pour être reconnu dans une société comme sachant agir ...

  17. Electrodynamics of the superconducting state in CeRu2

    International Nuclear Information System (INIS)

    We have studied the complex conductivity in superconducting and normal metallic states of CeRu2 by the surface impedance measurements at millimeter-wave frequency of 45.4 GHz. The temperature dependence of the complex conductivity below Tc = 6.2 K exhibits the characteristic behaviors as seen in a conventional superconductor. The coherence peak observed in the real part σ1 provides a strong evidence for a conventional s-wave superconductivity as well as the previous NQR measurements. The temperature dependence of the penetration depth evaluated from the surface reactance at low temperatures has revealed the ratio of 2Δ(0)/kBTc = 4.4. The strong-coupling theories suggest the electron-phonon coupling strength with λep 2 is an intermediate strong-coupling superconductor in a clean limit. (author)

  18. Complex magnetic states of heavy fermion compound CeGe

    International Nuclear Information System (INIS)

    The intermetallic compound CeGe exhibits unusual magnetic behavior due to the interplay between the Kondo and the antiferromagnetic coupling. This particular system is interesting because the Kondo temperature is close to the Neel temperature, resulting in a close competition between the low-temperature interactions, which can be tuned by means of varying external parameters such as pressure and applied magnetic field. Interestingly, magnetization measurements up to 12 kbar reveal that the Neel temperature is not affected by pressure. Measurements of the electrical resistivity, however, show that the sharp upturn appearing below TN is sensitive to pressures up to 15 kbar. This suggests that pressure may change the complex antiferromagnetic spin structure. The validity of an explanation based on the magnetic superzones seen in the rare earths is discussed here.

  19. Heavy Electron Behaviour of CeNi9Si4

    International Nuclear Information System (INIS)

    We have studied the phase formation, thermodynamic and transport properties of CeNi9Si4.The Rietveld refinement of the X-ray pattern confirms a fully ordered tetragonal crystal structure (space group I4 /mcm) that is derived from the cubic NaZn13 structure type. Resistivity, magnetic susceptibility and specific heat measurements reveal Kondo-lattice behaviour with an enhanced Pauli susceptibility χ0 = 0.005 emu/mol and a large Sommerfeld value γ = 155 (5) mJ/molK2. The magnetic contributions to the specific heat and the magnetic susceptibility are well described by the Coqblin-Schrieffer model with a fully degenerate J = 5/2 ground state and a characteristic temperature T0 ≅ 180 K. (author)

  20. Yield and gross income of bunching onion and coriander in monocrop and intercrop systems/ Produção e renda bruta de cebolinha e de coentro, em cultivo solteiro e consorciado

    Directory of Open Access Journals (Sweden)

    Cleila Marcondes de Souza

    2005-06-01

    Full Text Available The objective of this work was to determine yield and income of ‘Todo ano’ bunching onion and ‘Asteca’ coriander, which were carried out in monocrop and intercrop systems with three (Ce3 and Co3 and four rows planted per plot. The work was developed in Dourados-MS, Brazil, between July 13th, and September 15th, 2004. Average yield of fresh mass of bunching onion plants under monocrop system had significative increase of 0.64 t ha-1 (92.75% in relation to those under intercrop system (0.69 t ha-1. For coriander, yield of fresh mass of plants under monocrop system and with four rows per plot had significative increase of 1.43 t ha-1 (41.21% in relation to those under three rows (3.47 t ha-1. Land Equivalant Ratio (LER for bunching onion and coriander intercropped were superior in 21% (Ce3Co4 and 56% (Ce4Co3 in relation to monocrop system. For bunching onion producer, both intercrops were economic viable, but Ce4Co3 could have induced a higher gain per hectare (R$ 3,243.30. By the other side, for coriander producer, Ce3Co4 intercrop was the worst, because, although LER had been superior to 1.00, it could induce loss per hectare of R$ 99.42. Ce4Co3 intercrop was the best because it could induce a gain of R$ 777.77.O objetivo do trabalho foi determinar a produtividade e o retorno econômico da cebolinha ‘Todo Ano’ e do coentro ‘Asteca’, conduzidos em cultivo solteiro e consorciado, com três (Ce3 e Co3 e quatro (Ce4 e Co4 linhas de plantas por canteiro. O trabalho foi desenvolvido em Dourados-MS, entre 13 de julho e 15 de setembro de 2004. A produção média de massa fresca das plantas de cebolinha sob cultivo solteiro teve aumento significativo de 0,64 t ha-1 (92,75% em relação àquela sob consórcio (0,69 t ha-1. No coentro, a produção de massa fresca das plantas sob cultivo solteiro e com quatro linhas por canteiro teve aumento significativo de 1,43 t ha-1 (41,21% em relação à produção sob três linhas (3,47 t ha-1. As

  1. Synthesis and luminescence of CePO4 and CePO4:Tb hollow and core-shell microspheres composed of single-crystal nanorods

    International Nuclear Information System (INIS)

    Lanthanide phosphate microspheres composed of single-crystal CePO4 and CePO4:Tb nanorods were successfully synthesized, respectively, using the functionalized composite aggregate as a template, which is composed of P123, H6P4O13 and Ce3+, and also as a resource of reaction species with high chemical potential. The shape and the phase structure of the CePO4 nanocrystal can be easily controlled via adjusting reaction temperature, monomer concentration and annealing temperature. SEM images show the spherical superstructure composed of nanorods. HRTEM and SAED images reveal the single-crystalline nature of nanorod and TEM images show the hollow interiors of the superstructure. XRD patterns indicate that the crystal structure of the nanorods is hexagonal before and monoclinic after annealing. The formation mechanism was proposed. Strong UV and green luminescence were observed for the CePO4 and CePO4:Tb microspheres, respectively. The synthesis method can be extended to the fabrication of NRHS and core-shell microspheres of other rare-earth or doped LnPO4 materials for wide applications

  2. Spatial based Expectation Maximizing (EM)

    OpenAIRE

    Balafar M A

    2011-01-01

    Abstract Background Expectation maximizing (EM) is one of the common approaches for image segmentation. Methods an improvement of the EM algorithm is proposed and its effectiveness for MRI brain image segmentation is investigated. In order to improve EM performance, the proposed algorithms incorporates neighbourhood information into the clustering process. At first, average image is obtained as neighbourhood information and then it is incorporated in clustering process. Also, as an option, us...

  3. Preparation and characterization of Ce-doped ZnO nanofibers by an electrospinning method

    Directory of Open Access Journals (Sweden)

    Jong-Pil Kim

    2011-02-01

    Full Text Available ZnO and Ce-doped ZnO Nanofibers on (111 Pt/SiO2/Si substrates were produced using an electrospinning technique. The as-prepared composite fibres were subjected to high-temperature calcination to produce inorganic fibers. After calcining at a temperature of 500 °C, the average diameter of the ZnO and Ce-doped ZnO nanofibers were determined to be 170 nm and 225 nm, respectively. The average grain size of the ZnO and Ce-doped ZnO nanofibers were about 50 nm and 57 nm, respectively. The microstructure, chemical bonding state and photoluminescence of the produced ZnO and Ce-doped ZnO nanofibers were investigated. The Ce-doped ZnO nanofiber can be assigned to the presence of Ce ions on substitutional sites of Zn ions and the Ce3+ state from X-ray photoelectron spectra. Compared with PL spectra of ZnO nanofibers, the peak position of the UV emission of the Ce-doped ZnO nanofibers is sharply suppressed while the green emission band is highly enhanced.

  4. File list: His.CeL.05.AllAg.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.CeL.05.AllAg.AllCell dm3 Histone Cell line SRX193340,SRX193335,SRX193336,SRX201...RX143463,SRX017850 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/His.CeL.05.AllAg.AllCell.bed ...

  5. Crystal structure and physical properties of CePt2.4Al0.6

    International Nuclear Information System (INIS)

    Highlights: • New CePt2.4Al0.6 compound crystallizes in the hexagonal CeNi3-type (hP24, P63/mmc). • This crystal structure is a nearly ordered ternary derivative of CeNi3 prototype. • CePt2.4Al0.6 compound orders ferromagnetically at 1.6 K; Ce ions in trivalent state. • Magnetization, electrical resistivity, low-T heat capacity have been measured. • Negative magnetoresistivity below ∼15 K shows short-range FM in paramagnetic state. - Abstract: The new compound CePt2.4Al0.6 crystallizes in the hexagonal CeNi3-type (hP24, space group P63/mmc, N. 194), with lattice parameters a = 5.5203(3) Å and c = 16.886(1) Å; its crystal structure represents a nearly ordered ternary derivative of this prototype. The cerium ions in CePt2.4Al0.6 are in the normal trivalent state and order magnetically near 1.6 K as inferred from the low temperature heat capacity. The magnetic ordering is presumably ferromagnetic as suggested by the behavior of heat capacity in applied magnetic fields. The magnetoresistivity below ∼15 K is negative and is tentatively attributed to the presence of ferromagnetic short range order in the paramagnetic state

  6. Update History of This Database - tRNADB-CE | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available [ Credits ] BLAST Search Image Search Home About Archive Update History Contact us tRNADB-CE Update History... This Database Database Description Download License Update History of This Database Site Policy | Contact Us Update History of This Database - tRNADB-CE | LSDB Archive ...

  7. Influence of microgravity on Ce-doped Bi12SiO20 crystal defect

    Indian Academy of Sciences (India)

    Y F Zhou; J Y Xu; Y Liu; L D Chen; Y Y Huang; W X Huang

    2007-06-01

    Space grown BSO crystal doped with Ce was characterized by means of X-ray fluorescence spectra, X-ray topography, dislocation density etc. Influence of microgravity on Ce-doped BSO crystal defect was studied by comparing space grown BSO crystal with ground grown one. These results show that compositional homogeneity and structural perfection of crystal can be improved under microgravity conditions.

  8. Ordering and Fluctuation of Quantum Multipoles in CeB6

    International Nuclear Information System (INIS)

    The effect of multipolar fluctuations on the quadrupolar phase transition in CeB6 is investigated theoretically. It is shown that the fluctuations become strong and field-dependent, reflecting the competition of coupled multipolar interactions. Some unusual phenomena around the transition in CeB6 are shown to be reasonably explained within the RKKY model. (author)

  9. CeO2-covered nanofiber for highly efficient removal of phosphorus from aqueous solution.

    Science.gov (United States)

    Ko, Young Gun; Do, Taegu; Chun, Youngsang; Kim, Choong Hyun; Choi, Ung Su; Kim, Jae-Yong

    2016-04-15

    The lowering phosphorus concentration of lakes or rivers using adsorbents has been considered to be the most effective way to prevent water eutrophication. However, the development of an adsorbent is still challenging because conventional adsorbents have not shown a sufficient phosphorus adsorption capacity (0.3-2.0mmol/g) to treat industrial, agricultural or domestic wastewater at a large scale. Herein, a novel and effective strategy to remove phosphorus efficiently with a CeO2-covered nanofiber is shown. The CeO2-covered nanofiber was synthesized through (1) amine group immobilization onto an electrospun polyacrylonitrile nanofiber and (2) adsorption of Ce(3+) on it. The CeO2-covered nanofiber played a role in catching phosphate ions in an aqueous solution by the oxidation, reduction, and ion-exchange of adsorbed Ce(3+) on the nanofiber from CeO2 to CePO4, and enabled remarkable phosphate adsorption capacity of the nanofiber (ca. 17.0mmol/g) at the range of ca. pH 2-6. Our strategy might be the most feasible method to efficiently lower the phosphorus concentration in lakes or rivers owing to the easy and inexpensive preparation of CeO2-covered nanofiber at an industrial scale, with a high phosphate adsorption capacity. PMID:26795705

  10. Microstructure and corrosion behavior of electroless deposited Ni-P/CeO2 coating

    Institute of Scientific and Technical Information of China (English)

    Hui Ming Jin; Shi Hang Jiang; Lin Nan Zhang

    2008-01-01

    Electroless Ni-P/nano-CeO2 composite coating was prepared in acidic condition,and its microstructure and corrosive property were compared with its CeO2-free counterpart.Scanning electronic microscopy (SEM) and X-ray diffraction (XRD) spectrometer were used to examine surface morphology and structure of the as-plated coating.Differential scanning calorimeter (DSC) and transmission electronic microscopy (TEM) were used to study the coating's phase change at high temperature.The coating's corrosive behavior in 3%NaCI + 5%H2SO4 solution was also investigated.The results showed that Ni-P coating had partial amorphous structure mixed with nano-crystals,while the Ni-P/CeO2 coating had perfect amorphous structure.In high-temperature condition,Ni3P precipitation and Ni crystallization took place in both coatings but at different temperatures,while the Ni-P/CeO2 coating had sintered phase of NiCe2O4 spinels.The anti-corrosion property was better in the CeO2-containing coating,and this was due to its less liability to undergo local-cell corrosion than its CeO2-free counterpart.Ni-P/CeO2 coating's pure amorphous structure was the result of Ni's hindered crystal-typed deposition and P's promoted deposition.

  11. Structural characterization and corrosive property of Ni-P/CeO2composite coating

    Institute of Scientific and Technical Information of China (English)

    JIN Huiming; JIANG Shihang; ZHANG Linnan

    2009-01-01

    Electroless Ni-P/nano-CeO2 composite coating was prepared in acidic condition, and its microstructure and corrosive property were compared with its CeO2-free counterpart. Scanning electronic microscopy (SEM), transmission electronic microscopy (TEM), X-ray diffraction spectrometer (XRD), and differential scanning calorimeter (DSC) were used to examine surface morphology and microstructure of the coating. Corrosive investigation was carried out in 3%NaCl+5%H2SO4 solution. The results showed that Ni-P coating had partial amorphous structure mixed with nanocrystals, whereas the Ni-P/CeO2 coating had perfect amorphous structure. In high temperature condition, Ni3P precipitation and Ni crystallization occurred in both coatings but at different temperatures, whereas the Ni-P/CeO2 coating had sintered phase of NiCe2O4 spinels. The anticorrosion property and passivity were improved in the CeO2-containing coating due to its less liability to undergo local-cell corrosion than its CeO2-free counterpart. During the co-deposition process, some Cen+ (n=3, 4) ions may be adsorbed to the metal/solution interface, hinder nickel's crystal-typed deposition and promote phosphorous deposition. The nano-CeO2 doping finally resulted in the coating' perfect amorphous structure and good anti-corrosive property.

  12. Facile synthesis of ferromagnetic Ni doped CeO2 nanoparticles with enhanced anticancer activity

    Science.gov (United States)

    Abbas, Fazal; Jan, Tariq; Iqbal, Javed; Ahmad, Ishaq; Naqvi, M. Sajjad H.; Malik, Maaza

    2015-12-01

    NixCe1-xO2 (where x = 0, 0.01, 0.03, 0.05 and 0.07) nanoparticles were synthesized by soft chemical method and were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman, UV-vis absorption spectroscopy and vibrating sample magnetometer (VSM). XRD and Raman results indicated the formation of single phase cubic fluorite structure for the synthesized nanoparticles. Ni dopant induced excessive structural changes such as decrease in crystallite size as well as lattice constants and enhancement in oxygen vacancies in CeO2 crystal structure. These structural variations significantly influenced the optical and magnetic properties of CeO2 nanoparticles. The synthesized NixCe1-xO2 nanoparticles exhibited room temperature ferromagnetic behavior. Ni doping induced effects on the cytotoxicity of CeO2 nanoparticles were examined against HEK-293 healthy cell line and SH-SY5Y neuroblastoma cancer cell line. The prepared NixCe1-xO2 nanoparticles demonstrated differential cytotoxicity. Furthermore, anticancer activity of CeO2 nanoparticles observed to be significantly enhanced with Ni doping which was found to be strongly correlated with the level of reactive oxygen species (ROS) production. The prepared ferromagnetic NixCe1-xO2 nanoparticles with differential cytotoxic nature may be potential for future targeted cancer therapy.

  13. Research on Public Signs and the Importance of this Research to C-E Translation

    Institute of Scientific and Technical Information of China (English)

    唐燕

    2012-01-01

    There is increasing recognition of the importance and usefulness of doing research in C-E translation of public signs. As bilingual signs are increasingly popular, considerable attention should be paid to the study of C-E translation of public signs. It is theoretically and practically urgent to make a further study and research on public signs systematically.

  14. File list: Oth.CeL.10.Epitope_tags.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.CeL.10.Epitope_tags.AllCell dm3 TFs and others Epitope tags Cell line SRX099635...099636 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/Oth.CeL.10.Epitope_tags.AllCell.bed ...

  15. Luminescence from Ce in sol-gel SiO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Kroon, R.E., E-mail: KroonRE@ufs.ac.za [Department of Physics, University of the Free State, IB51, Box 339, Bloemfontein 9300 (South Africa); Seed Ahmed, H.A.A.; Ntwaeaborwa, O.M. [Department of Physics, University of the Free State, IB51, Box 339, Bloemfontein 9300 (South Africa); Koao, L.F. [Department of Physics, University of the Free State (Qwaqwa Campus), Private Bag X13, Phuthaditjhaba 9866 (South Africa); Nagpure, I.M.; Gusowski, M.A. [Department of Physics, University of the Free State, IB51, Box 339, Bloemfontein 9300 (South Africa); Botha, J.R. [Department of Physics, Nelson Mandela Metropolitan University, Box 77000, Port Elizabeth 6031 (South Africa); Swart, H.C. [Department of Physics, University of the Free State, IB51, Box 339, Bloemfontein 9300 (South Africa)

    2012-05-15

    The sol-gel process provides an attractive low temperature alternative to the melt process for producing Ce-doped silica, but reports of the emission wavelength have not been consistent. In this paper, luminescence measurements using a variety of excitation methods, including cathodoluminescence not yet reported by other researchers, are compared and evaluated in the light of previously published data. Several papers report luminescence around 350 nm but emission near this wavelength was not found from our samples. This luminescence originates from Ce that has not yet been incorporated in the silica and is found in samples that have not undergone high temperature annealing. Our photoluminescence results from samples annealed in a reducing atmosphere suggest that emission from Ce incorporated in the silica lattice occurs near 455 nm, and some indication of the emission from Ce in amorphous clusters at 400 nm is also found. However, our results also confirm earlier indications that intrinsic defects in silica can create photoluminescence near both these wavelengths, which can make identification of the luminescence due to Ce difficult. Finally, it has been found that samples which have been annealed in air, and therefore display poor photoluminescence because most of the Ce occurs in the tetravalent form, are luminescent under electron beam excitation. It is suggested that during cathodoluminescence measurements Ce{sup 4+} ions capture electrons to form excited Ce{sup 3+} ions from which the luminescence originates.

  16. File list: Oth.CeL.05.ash1.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.CeL.05.ash1.AllCell dm3 TFs and others ash1 Cell line SRX084580,SRX128300,SRX12...8301,SRX084579 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/Oth.CeL.05.ash1.AllCell.bed ...

  17. File list: Oth.CeL.20.ash1.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.CeL.20.ash1.AllCell dm3 TFs and others ash1 Cell line SRX128301,SRX084579,SRX08...4580,SRX128300 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/Oth.CeL.20.ash1.AllCell.bed ...

  18. File list: Oth.CeL.10.ash1.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.CeL.10.ash1.AllCell dm3 TFs and others ash1 Cell line SRX128300,SRX084580,SRX08...4579,SRX128301 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/Oth.CeL.10.ash1.AllCell.bed ...

  19. File list: Oth.CeL.50.ash1.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.CeL.50.ash1.AllCell dm3 TFs and others ash1 Cell line SRX128301,SRX084579,SRX08...4580,SRX128300 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/Oth.CeL.50.ash1.AllCell.bed ...

  20. Photocatalytic and antibacterial properties of phytosynthesized CeO2 NPs using Moringa oleifera peel extract.

    Science.gov (United States)

    Surendra, T V; Roopan, Selvaraj Mohana

    2016-08-01

    Biosynthetic methods are alternative approaches which are much safer than the normal techniques (physical and chemical) used for the methods for synthesis of metal nanoparticles. The benefits are sample as it is economic and environment friendly. Herein present investigation, we have reported a microwave mediated eco-friendly synthetic approach for preparing cerium oxide (CeO2) nanoparticles. Here, we used Moringa oleifera peel as the stabilizing and reducing agent towards synthesize of Ce2O NPs via microwave irradiation. The NPs were further characterized using UV-Vis, FT-IR, XRD and HR-TEM techniques. The FTIR analysis confirmed the phytochemical involvement in NPs stabilization. The crystallinity of CeO2 nanoparticles are well demonstrated through X-ray Diffraction and HR-TEM. The TEM images reveal the spherical shape of the CeO2 NPs having an average size of 45nm. Additionally, these CeO2 NPs were used successfully as a catalyst in the degradation of the dye, crystal violet. Also the antibacterial activity of the synthesized CeO2 NPs was evaluated using Staphylococcus aureus (Gram positive bacteria) and Escherichia coli (Gram negative bacteria). CeO2 NPs showed better activity on E. coli than S. aureus. We have demonstrated an eco-friendly preparation of CeO2 nanoparticles, a good photocatalyst and having better antibacterial properties. PMID:27236047

  1. Optical properties of pure and Ce3+ doped gadolinium gallium garnet crystals and epitaxial layers

    International Nuclear Information System (INIS)

    Results of X-ray diffraction and low temperature optical absorption measurements of cerium doped gadolinium gallium garnet single crystals and epitaxial layers are reported. In the region of intra-configurational 4f–4f transitions the spectra of the bulk crystals exhibit the signatures of several different Ce3+ related centers. Apart from the dominant center, associated with Ce substituting gadolinium, at least three other centers are found, some of them attributed to the so-called antisite locations of rare-earth ions in the garnet host, i.e., in the Ga positions. X-ray diffraction data prove lattice expansion of bulk GGG crystals due to the presence of rare-earth antisites. The concentration of the additional Ce-related centers in epitaxial layers is much lower than in the bulk crystals. However, the Ce-doped layers incorporate a large amount of Pb from flux, which is the most probable source of nonradiative quenching of Ce luminescence, not observed in crystals grown by the Czochralski method. - Highlights: • Ce3+ multicenters found in Gadolinium Gallium Garnet crystals and epitaxial layers. • High quality epitaxial layers of pure and Ce-doped GGG were grown. • Luminescence quenching of Ce3+ by Pb ions from flux detected in GGG epitaxial layers. • X-ray diffraction allows measuring the amount of the rare-earth antisites in GGG

  2. File list: Pol.CeL.05.AllAg.Kc167 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.CeL.05.AllAg.Kc167 dm3 RNA polymerase Cell line Kc167 SRX331419,SRX331420,SRX31...8797,SRX318796,SRX749070,SRX749073,SRX749071,SRX331416,SRX331415,SRX749072 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/Pol.CeL.05.AllAg.Kc167.bed ...

  3. File list: Pol.CeL.05.AllAg.OSC [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.CeL.05.AllAg.OSC dm3 RNA polymerase Cell line OSC SRX201898,SRX201896,SRX201894...,SRX201897,SRX201899,SRX318811,SRX315134,SRX201895,SRX315132,SRX315133 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/Pol.CeL.05.AllAg.OSC.bed ...

  4. File list: Pol.CeL.50.AllAg.OSC [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.CeL.50.AllAg.OSC dm3 RNA polymerase Cell line OSC SRX201898,SRX201897,SRX201899...,SRX201894,SRX201895,SRX315132,SRX201896,SRX315134,SRX315133,SRX318811 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/Pol.CeL.50.AllAg.OSC.bed ...

  5. File list: Oth.CeL.50.Trl.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.CeL.50.Trl.AllCell dm3 TFs and others Trl Cell line SRX183520,SRX183521,SRX0254...89,SRX397055,SRX300931 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/Oth.CeL.50.Trl.AllCell.bed ...

  6. File list: Oth.CeL.20.Trl.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.CeL.20.Trl.AllCell dm3 TFs and others Trl Cell line SRX183520,SRX183521,SRX0254...89,SRX397055,SRX300931 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/Oth.CeL.20.Trl.AllCell.bed ...

  7. File list: Pol.CeL.20.AllAg.Kc167 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.CeL.20.AllAg.Kc167 dm3 RNA polymerase Cell line Kc167 SRX331416,SRX331415,SRX33...1420,SRX318796,SRX331419,SRX318797,SRX749070,SRX749072,SRX749071,SRX749073 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/Pol.CeL.20.AllAg.Kc167.bed ...

  8. File list: Pol.CeL.50.AllAg.Kc167 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.CeL.50.AllAg.Kc167 dm3 RNA polymerase Cell line Kc167 SRX331416,SRX331415,SRX33...1420,SRX318796,SRX331419,SRX318797,SRX749070,SRX749072,SRX749071,SRX749073 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/Pol.CeL.50.AllAg.Kc167.bed ...

  9. File list: Oth.CeL.10.Trl.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.CeL.10.Trl.AllCell dm3 TFs and others Trl Cell line SRX300931,SRX397055,SRX1835...20,SRX183521,SRX025489 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/Oth.CeL.10.Trl.AllCell.bed ...

  10. File list: Pol.CeL.10.AllAg.Kc167 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.CeL.10.AllAg.Kc167 dm3 RNA polymerase Cell line Kc167 SRX331419,SRX318797,SRX31...8796,SRX749070,SRX749071,SRX331416,SRX331415,SRX331420,SRX749072,SRX749073 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/Pol.CeL.10.AllAg.Kc167.bed ...

  11. File list: Oth.CeL.05.Trl.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.CeL.05.Trl.AllCell dm3 TFs and others Trl Cell line SRX300931,SRX397055,SRX1835...20,SRX183521,SRX025489 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/Oth.CeL.05.Trl.AllCell.bed ...

  12. File list: Pol.CeL.20.AllAg.OSC [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.CeL.20.AllAg.OSC dm3 RNA polymerase Cell line OSC SRX201898,SRX201897,SRX318811...,SRX201899,SRX201894,SRX201895,SRX315132,SRX201896,SRX315134,SRX315133 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/Pol.CeL.20.AllAg.OSC.bed ...

  13. File list: Pol.CeL.10.AllAg.OSC [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.CeL.10.AllAg.OSC dm3 RNA polymerase Cell line OSC SRX201896,SRX318811,SRX201898...,SRX201899,SRX201897,SRX201894,SRX201895,SRX315132,SRX315134,SRX315133 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/Pol.CeL.10.AllAg.OSC.bed ...

  14. Specific heat of CePtSi in a high magnetic field

    International Nuclear Information System (INIS)

    We present specific-heat measurements on CePtSi in 0- and in 13-T magnetic field. There is no significant deviation between the two sets of data. This gives further evidence that CePtSi is a heavy-fermion compound and that magnetic correlations as a reason for the large specific heat γ can be excluded

  15. Scintillation and optical stimulated luminescence of Ce-doped CaF2

    International Nuclear Information System (INIS)

    Scintillation and optical stimulated luminescence of Ce 0.1–20% doped CaF2 crystals prepared by Tokuyama Corp. were investigated. In X-ray induced scintillation spectra, luminescence due to Ce3+ 5d–4f transition appeared around 320 nm with typically 40 ns decay time. By 241Am 5.5 MeV α-ray irradiation, 0.1% doped one showed the highest scintillation light yield and the light yield monotonically decreased with Ce concentrations. Optically stimulated luminescence after X-ray irradiation was observed around 320 nm under 550 or 830 nm stimulation in all samples. As a result, intensities of optically stimulated luminescence were proportional to Ce concentrations. Consequently, scintillation and optically stimulated luminescence resulted to have a complementary relation in Ce-doped CaF2 system. - Highlights: • Optical, scintillation, and OSL properties of Ce 0.1–20% doped CaF2 were studied. • Scintillation light yield exhibited inverse proportionality to Ce concentrations. • OSL intensities showed proportionality to Ce concentrations. • Complementary relation of scintillation and OSL was experimentally confirmed

  16. Incommensurate antiferromagnetism and magnetic correlations in CeCu6-xAux

    DEFF Research Database (Denmark)

    Stockert, O.; Lohneysen, H. von; Schröder, A.;

    1997-01-01

    Magnetic ordering and correlations in single crystals of the heavy-fermion alloys CeCu5.8Au0.2 and CeCu5.9Au0.1 were investigated by elastic and inelastic neutron scattering. CeCu5.8Au0.2 orders with an incommensurate magnetic structure and a wave vector q = (+/- 0.79 0 0). Only dynamic antiferro......Magnetic ordering and correlations in single crystals of the heavy-fermion alloys CeCu5.8Au0.2 and CeCu5.9Au0.1 were investigated by elastic and inelastic neutron scattering. CeCu5.8Au0.2 orders with an incommensurate magnetic structure and a wave vector q = (+/- 0.79 0 0). Only dynamic...... antiferromagnetic correlations along a* are observed in CeCu5.9Au0.1 which evolve into a static sine modulation in CeCu5.8Au0.2....

  17. Preparation and characterization of Ce-doped HfO{sub 2} nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Gálvez-Barboza, S. [Centro de Investigación en Química Aplicada, Departamento de Materiales Avanzados, Blvd. Enrique Reyna Hermosillo #140, C.P. 25294 Saltillo, Coahuila (Mexico); Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Av. Industria Metalúrgica # 1062 Parque Industrial, C.P. 25900 Ramos Arizpe, Coahuila (Mexico); González, L.A. [Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Av. Industria Metalúrgica # 1062 Parque Industrial, C.P. 25900 Ramos Arizpe, Coahuila (Mexico); Puente-Urbina, B.A.; Saucedo-Salazar, E.M. [Centro de Investigación en Química Aplicada, Departamento de Materiales Avanzados, Blvd. Enrique Reyna Hermosillo #140, C.P. 25294 Saltillo, Coahuila (Mexico); García-Cerda, L.A., E-mail: luis.garcia@ciqa.edu.mx [Centro de Investigación en Química Aplicada, Departamento de Materiales Avanzados, Blvd. Enrique Reyna Hermosillo #140, C.P. 25294 Saltillo, Coahuila (Mexico)

    2015-09-15

    Highlights: • Ce-doped HfO{sub 2} nanoparticles were prepared by a modified solgel method. • Ce-doped HfO{sub 2} nanoparticles have a semispherical shape with sizes between 6 and 11.5 nm. • The samples doped with 10% in weight of Ce directly crystallized in a cubic structure. • A quick, straightforward and effective route for the preparation of Ce-doped nanoparticles. - Abstract: A modified solgel method to synthesize Ce-doped HfO{sub 2} nanoparticles was carried out using a precursor material prepared with cerium nitrate, hafnium chloride, citric acid and ethylene glycol. The obtained precursor material was calcined at 500 and 700 °C for 2 h in air. The influence of the concentration of Ce and the calcination temperature was studied to observe the structural and morphological changes of the obtained materials. For the characterization, X-ray diffraction (XRD), transmission electron microscopy (TEM) and Raman scattering (RS) were employed. The XRD patterns shown that the Ce-doped HfO{sub 2} undergoes a structural transformation from monoclinic to cubic phase, which is significantly dependent on the Ce content and calcination temperature. TEM images have also confirmed the existence of semispherical nanoparticles with sizes between 6 and 11.5 nm.

  18. Preparation and characterization of Ce-doped HfO2 nanoparticles

    International Nuclear Information System (INIS)

    Highlights: • Ce-doped HfO2 nanoparticles were prepared by a modified solgel method. • Ce-doped HfO2 nanoparticles have a semispherical shape with sizes between 6 and 11.5 nm. • The samples doped with 10% in weight of Ce directly crystallized in a cubic structure. • A quick, straightforward and effective route for the preparation of Ce-doped nanoparticles. - Abstract: A modified solgel method to synthesize Ce-doped HfO2 nanoparticles was carried out using a precursor material prepared with cerium nitrate, hafnium chloride, citric acid and ethylene glycol. The obtained precursor material was calcined at 500 and 700 °C for 2 h in air. The influence of the concentration of Ce and the calcination temperature was studied to observe the structural and morphological changes of the obtained materials. For the characterization, X-ray diffraction (XRD), transmission electron microscopy (TEM) and Raman scattering (RS) were employed. The XRD patterns shown that the Ce-doped HfO2 undergoes a structural transformation from monoclinic to cubic phase, which is significantly dependent on the Ce content and calcination temperature. TEM images have also confirmed the existence of semispherical nanoparticles with sizes between 6 and 11.5 nm

  19. Recent advances in CE-MS: Synergy of wet chemistry and instrumentation innovations.

    Science.gov (United States)

    Pantůčková, Pavla; Gebauer, Petr; Boček, Petr; Křivánková, Ludmila

    2011-01-01

    CE with MS detection is a hyphenated technique which greatly improves the ability of CE to deal with real samples, especially with those coming from biology and medicine, where the target analytes are present as trace amounts in very complex matrices. CE-MS is now almost a routine technique performed on commercially available instruments. It faces currently a tremendous development of the technique itself as well as of its wide application area. Great interest in CE-MS is reflected in the scientific literature by many original research articles and also by numerous reviews. The review presented here has a general scope and belongs to a series of regularly published reviews on the topic. It covers the literature from the last 2 years, since January 2008 till June 2010. It brings a critical selection of related literature sorted into groups reflecting the main topics of actual scientific interest: (i) innovations in CE-ESI-MS, (ii) use of alternative interfaces, and (iii) ways to enhance sensitivity. Special attention is paid to novel electrolyte systems amenable to CE-MS including nonvolatile BGEs, to advanced CE separation principles such as MEKC, MEEKC, chiral CE, and to the use of preconcentration techniques. PMID:21171112

  20. Assembly of large purely inorganic Ce-stabilized/bridged selenotungstates: from nanoclusters to layers.

    Science.gov (United States)

    Chen, Wei-Chao; Qin, Chao; Li, Yang-Guang; Zang, Hong-Ying; Shao, Kui-Zhan; Su, Zhong-Min; Wang, En-Bo

    2015-05-01

    A versatile one-pot strategy was used to synthesize two large, purely inorganic selenotungstates, nanocluster K(6)Na(16) [Ce(6)Se(6)W(67)O(230) (OH)(6) (H(2)O)(17)]⋅47 H(2)O (1) and layer K(9)Na(5) Ce(H(2)O)(4) [Ce(6)Se(10)W(51)O(187) (OH)(7) (H(2)O)(18)]⋅45H(2)O(2), by combining cerium centers and SeO(3) (2-) heteroanion templates. Compound 1 displays a Ce-stabilized hexameric nanocluster with one rhombus-like {W(4)O(15) (OH)(3)} unit in the center, whereas compound 2 is the first example of a Ce-bridged layer selenotungstate network based on linkage of the unusual {Ce(6)Se(10)W(51)O(187) (OH)(7) (H(2)O)(18)} clusters and additional Ce(H(2)O)(4) fragments via Ce-O-Se bridges. The compounds were characterized by elemental analyses, IR spectroscopy, thermogravimetric analyses, powder and single-crystal X-ray diffraction, and electrospray ionization mass spectrometry. Moreover, the electrochemical property of compound 1 was also investigated. PMID:25641950

  1. Valence-band photoemission in La and Pr: Connections with the Ce problem

    International Nuclear Information System (INIS)

    Energy distribution curves from La and Pr were taken from 32 to 80 eV photon energies. Above 50 eV the valence-band photoemission in La is very weak, implying that previous studies of Ce have underemphasized the 4f contributions. Pr exhibits two peaks attributable to 4f electrons, similar to the structures in Ce

  2. Crystal structure and physical properties of Ce3Rh5Si

    International Nuclear Information System (INIS)

    Highlights: ► The formation of novel compound Ce3Rh5Si was established. ► A new type of crystal structure was recognized. ► The low-temperature magnetic and electrical behavior of Ce3Rh5Si was determined. - Abstract: The crystal structure of the novel compound Ce3Rh5Si was solved by means of powder diffraction pattern analysis using the charge-flipping method. The refinements yielded the space group Pnma and the orthorhombic unit cell parameters: a = 1.52632(2) nm, b = 0.55092(1) nm, and c = 0.75302(1) nm. A characteristic feature of the crystal structure of Ce3Rh5Si are vertex-sharing [Rh4] and [Rh3Si] tetrahedra, which form a three-dimensional framework with Ce atoms located inside truncated tetrahedral voids. The structure exhibits close relationship with those of CeRh2 (MgCu2-type) and Ce2Rh3Si (Y2Rh3Si-type). Magnetic and electrical resistivity measurements of Ce3Rh5Si were performed down to 2 K. The compound was characterized as a Pauli paramagnet with metallic character of the electrical conductivity.

  3. Anomalous compressive behavior in CeO2 nanocubes under high pressure

    DEFF Research Database (Denmark)

    Ge, M. Y.; Fang, Y. Z.; Wang, H.;

    2008-01-01

    is found to be 10 GPa for 4.7 nm and 16 GPa for 5.6 nm CeO2 nanocubes. The particle size dependence of the threshold pressure for the hardening of CeO2 nanoparticles is quite unusual. First-principles electronic calculations show that the increased bulk modulus of the nanocrystal is due...

  4. LiCl(NaCl)-CeCl3-H2O systems at 25 deg C

    International Nuclear Information System (INIS)

    It has been found by the method of isothermal solubility that aqueous ternary systems LiCl(NaCl)-CeCl3-H2O at 25 deg C refer to the eutonic type with crystallization of the initial components LiClxH2O, NaCl, and CeCl3x7H2O

  5. Microstructure and oxygen evolution of Fe-Ce mixed oxides by redox treatment

    Science.gov (United States)

    Li, Kongzhai; Haneda, Masaaki; Ning, Peihong; Wang, Hua; Ozawa, Masakuni

    2014-01-01

    The relationship between structure and reduction/redox properties of Fe-Ce mixed oxides with a Fe content of 5, 10, 20 or 30 mol%, prepared by a coprecipitation method, were investigated by XRD, Raman, TEM, TPR and TPO techniques. It is found that all the iron ions can be incorporated into the ceria lattice to form a solid solution for the FeCe 5 (Fe 5%) sample, but amorphous or crystal Fe2O3 particles were found to be present on the Fe-Ce oxide samples with higher the iron content. The reducibility of single solid solution was much better than the pure CeO2, and the appearance of dispersed Fe2O3 particles improved the surface reducibility of materials. The iron ions incorporated into the CeO2 lattice accelerated the oxygen release from bulk to surface, and surface Fe2O3 particles in close contact to CeO2 acted as a catalyst for the reaction between solid solution and hydrogen. The microstructure of exposed Fe2O3 with Ce-Fe-O solid solution allows the Fe-Ce mixed oxides to own good reducibility and high OSC, which also counteracts the deactivation of the reducibility resulting from the sintering of materials in the redox cycling.

  6. Intermediate-valent CeCoAl. A commensurate modulated structure with short Ce-Co distances

    Energy Technology Data Exchange (ETDEWEB)

    Niehaus, Oliver; Hoffmann, Rolf-Dieter; Poettgen, Rainer [Univ. Muenster (Germany). Inst. fuer Anorganische und Analytische Chemie; Tence, Sophie; Chevalier, Bernard [CNRS Bordeaux Univ., Pessac (France). ICMCB, UPR 9048

    2015-11-01

    CeCoAl was synthesized by melting of the elements in a sealed niobium tube in an induction furnace. Annealing of the sample gave access to a single phase sample. Its structure was refined on the basis of single-crystal X-ray diffractometer data at different temperatures. Above 271 K CeCoAl crystallizes in its own structure type in the space group C2/m [a = 1107.4(2), b = 440.6(1) and c = 479.6(1) pm, β = 104.6(1) {sup circle} ]. Data obtained at 300 K lead to 511 F{sup 2} values with 20 variables and a residual of [I ≥ 3σ(I)] wR = 0.0539. Below 271 K satellites give rise to the superspace group C2/m(α0γ)00; α = 2/3, γ = 2/5 with a temperature independent q-vector. For the 90 K data (also for 180 and 220 K) the commensurate modulated structure could be refined with 4817 F{sup 2} values, 129 variables and residuals of wR = 0.0347 (main), wR = 0.1927 (satellites 1st order), wR = 0.1541 (satellites 2nd order) and wR = 0.1768 (satellites 3rd order) [a = 1107.5(1), b = 440.3(1) and c = 479.0(1) pm, β = 104.7(1) {sup circle} ]. For the three temperatures only minor variations of the modulation amplitudes are observed. The relation of the low temperature (3+1)D 3a x 5c approximant and the room temperature 3D structure is discussed on the basis of a group-subgroup relation. By investigation of the heat capacity, the phase transition could be identified as a second order one with a transition temperature of 271 K. Magnetic measurements clearly prove the intermediate cerium valence which is in line with the short Ce-Co distances.

  7. Synthesis and Spectroscopic Analysis of Novel 1<em>H-Benzo[d>]imidazoles Phenyl Sulfonylpiperazines

    Directory of Open Access Journals (Sweden)

    Amjad M. Qandil

    2012-05-01

    Full Text Available A group of benzimidazole analogs of sildenafil, 3-benzimidazolyl-4-methoxy-phenylsulfonylpiperazines 2–4 and 3-benzimidazolyl-4-methoxy-<em>N,N>-dimethyl- benzenesulfonamide (5, were efficiently synthesized. Compounds 2–5 were characterized by NMR and MS and contrary to the reported mass spectra of sildenafil, the spectra of the piperazine-containing compounds 2–4 showed a novel fragmentation pattern leading to an <em>m/z> = 316. A mechanism for the formation of this fragment was proposed.

  8. Valence fluctuation in CeMo{sub 2}Si{sub 2}C

    Energy Technology Data Exchange (ETDEWEB)

    Paramanik, U.B.; Anupam [Department of Physics, Indian Institute of Technology, Kanpur 208 016 (India); Burkhardt, U. [Max-Planck Institute for Chemical Physics of Solids, 01187 Dresden (Germany); Prasad, R. [Department of Physics, Indian Institute of Technology, Kanpur 208 016 (India); Geibel, C. [Max-Planck Institute for Chemical Physics of Solids, 01187 Dresden (Germany); Hossain, Z., E-mail: zakir@iitk.ac.in [Department of Physics, Indian Institute of Technology, Kanpur 208 016 (India)

    2013-12-15

    Highlights: •Evidence for valence fluctuation of Ce ions. •XAS provides average formal LIII valence of Ce. •Kadowaki Woods ratio and Sommerfeld Wilson ratio indicate Fermi-liquid behavior. •DFT calculations reveal strong hybridization between Ce 4f and Mo 4d states. -- Abstract: We report on the valence fluctuation of Ce in CeMo{sub 2}Si{sub 2}C as studied by means of magnetic susceptibility χ(T), specific heat C(T), electrical resistivity ρ(T) and X-ray absorption spectroscopy. Powder X-ray diffraction revealed that CeMo{sub 2}Si{sub 2}C crystallizes in CeCr{sub 2}Si{sub 2}C-type layered tetragonal crystal structure (space group P4/mmm). The unit cell volume of CeMo{sub 2}Si{sub 2}C deviates from the expected lanthanide contraction, indicating non-trivalent state of Ce ions in this compound. The observed weak temperature dependence of the magnetic susceptibility and its low value indicate that Ce ions are in valence fluctuating state. The formal L{sub III} Ce valence in CeMo{sub 2}Si{sub 2}C〈ν{sup ∼}〉=3.14 as determined from X-ray absorption spectroscopy measurement is well below the value 〈ν{sup ∼}〉≃3.4 in tetravalent Ce compound CeO{sub 2}. The temperature dependence of specific heat does not show any anomaly down to 1.8 K which rules out any magnetic ordering in the system. The Sommerfeld coefficient obtained from the specific heat data is γ = 23.4 mJ/mol K{sup 2}. The electrical resistivity follows the T{sup 2} behavior in the low temperature range below 35 K confirming a Fermi liquid behavior. Accordingly both the Kadowaki Woods ratio A/γ{sup 2} and the Sommerfeld Wilson ratio χ(0)/γ are in the range expected for Fermi-liquid systems. In order to get some information on the electronic states, we calculated the band structure within the density functional theory, eventhough this approach is not able to treat 4f electrons accurately. The non-f electron states crossing the Fermi level have mostly Mo 4d character. They provide the

  9. Standard molar enthalpy of formation of Ce2Zr2O8

    International Nuclear Information System (INIS)

    Highlights: • Cerium zirconate (Ce2Zr2O8) has been synthesized and characterized. • The ΔHdissolution of CeO2(s), ZrO2(s), Ce2Zr2O8(s) and Ce2Zr2O8(s) (decomp) have been measured. • ΔfH°298 of Ce2Zr2O8(s) was found to be −(4344.0 ± 4.0) kJ mol−1. - Abstract: Cerium zirconate, Ce2Zr2O8(s), is an interesting material having potential applications such as matrix for immobilization of nuclear waste, component in the inert matrix fuel, oxygen storage capacitor and catalyst for chemical reactions, etc. Long term stability of the compound under reactive conditions is essential for its utilization. Thermodynamics plays an important role in predicting the stability of the material. The present paper describes determination of the standard molar enthalpy of formation (ΔfH°298) of Ce2Zr2O8(s) employing a high temperature solution calorimeter. The enthalpies of dissolution of CeO2(s), ZrO2(s), Ce2Zr2O8(s) in liquid Na2O + MoO3 solvent (3:4 M ratio) at 986 K were measured employing a Calvet Calorimeter. The standard molar enthalpy of formation of the compound at 298 K (ΔfH°298) was calculated by combining the experimentally determined values of the reaction enthalpies with the auxiliary data from the literature. The standard molar enthalpy of formation (ΔfH°298) of Ce2Zr2O8 was found to be –(4344.0 ± 4.0) kJ mol−1. Ce2Zr2O8(s) is a metastable compound, which decomposes to Ce-rich ZrO2 and Zr-rich CeO2 fluorite-type phases, when heated above 1673 K. The extent of metastability of Ce2Zr2O8 compared to its stable decomposed products has been determined

  10. Investigation on the nature of active species in the CeCl{sub 3}-doped sodium alanate system

    Energy Technology Data Exchange (ETDEWEB)

    Fan Xiulin; Xiao Xuezhang [Department of Materials Science and Engineering, Zhejiang University, 38 Zheda Road, Hangzhou 310027 (China); Chen Lixin, E-mail: lxchen@zju.edu.cn [Department of Materials Science and Engineering, Zhejiang University, 38 Zheda Road, Hangzhou 310027 (China); Li Shouquan; Wang Qidong [Department of Materials Science and Engineering, Zhejiang University, 38 Zheda Road, Hangzhou 310027 (China)

    2011-09-15

    Research highlights: > The additive of CeCl{sub 3} is reduced in doping process, causing the formation of NaCl and highly dispersed Ce species. > After dehydrogenation, Al-Ce alloy with a structure of CeAl{sub 4} comes into being and remains almost unchanged in the following cycles. > Directly doping CeAl{sub 4} into the system results in much similar kinetics. - Abstract: CeCl{sub 3}-doped NaAlH{sub 4} was directly synthesized in hydrogenation process using NaH/Al with 2 mol% CeCl{sub 3} under ball-milling. X-ray diffraction was utilized to unveil the nature of cerium during NaAlH{sub 4} synthesis process and succedent cycling. It is found that, CeCl{sub 3} is reduced in the ball-milling process and following cycles, causing the formation of NaCl and Al-Ce alloy with a structure of CeAl{sub 4}. The catalytic enhancement arising upon doping the ball-milled CeAl{sub 4} alloy is quite similar to that achieved in the CeCl{sub 3}-doped sodium alanate. Because the CeAl{sub 4} dopant does not consume the effective hydrogen storage component, the CeAl{sub 4}-doped NaAlH{sub 4} exhibits more hydrogen storage capacity. Moreover, CeCl{sub 3}-doped NaAlH{sub 4} and CeAl{sub 4}-doped NaAlH{sub 4} exhibit similar apparent activation energies estimated from Kissinger's method, suggesting the reactions are all determined by the same rate-limiting step. These results clearly demonstrate that the in situ formed CeAl{sub 4} acts as active species to catalyze the reversible dehydriding/rehydriding of NaAlH{sub 4}.

  11. High efficiency energy transfer in Ce,Tb co-doped silica prepared by sol-gel method

    International Nuclear Information System (INIS)

    Amorphous Ce,Tb co-doped silica (SiO2) was prepared using the sol-gel method with the aim of studying the energy transfer from Ce to Tb ions. It was initially found that adding Ce reduced the Tb emission intensity, implying that energy transfer did not occur. In fact, the Ce single doped sample exhibited very poor emission. Ultraviolet-visible diffuse reflectance measurements displayed the signature of non-luminescent Ce4+ rather than Ce3+ ions. We therefore annealed the samples in a reducing atmosphere of 4% hydrogen in argon gas at 1000 °C. The reduced Ce single doped samples exhibited bright luminescence and the diffuse reflectance measurements now showed the characteristic of Ce3+ ions. The reduced Ce,Tb co-doped samples excited at the Ce absorption wavelength gave characteristic Tb emission (with negligible Ce emission), indicating that very efficient energy transfer from Ce to Tb was achieved. For samples containing 1 mol% Tb, the maximum luminescence was found when co-doping with 0.5 mol% Ce. Using such co-doped silica samples exhibiting energy transfer, it is possible to obtain effective luminescence from the Tb3+ ions via excitation of Ce3+ ions at 325 nm, instead of exciting the Tb3+ ions directly which requires a shorter wavelength of about 227 nm. - Highlights: ► Vast improvement in energy transfer from Ce to Tb in sol-gel silica. ► Tb doped silica effectively excited at 325 nm instead of 227 nm after Ce co-doping. ► Improved annealing process for sol-gel silica with Ce for luminescence applications.

  12. Proximate Composition, Nutritional Attributes and Mineral Composition of <em>Peperomia> <em>pellucida> L. (Ketumpangan Air Grown in Malaysia

    Directory of Open Access Journals (Sweden)

    Maznah Ismail

    2012-09-01

    Full Text Available This study presents the proximate and mineral composition of <em>Peperomia> <em>pellucida> L., an underexploited weed plant in Malaysia. Proximate analysis was performed using standard AOAC methods and mineral contents were determined using atomic absorption spectrometry. The results indicated <em>Peperomia> <em>pellucida> to be rich in crude protein, carbohydrate and total ash contents. The high amount of total ash (31.22% suggests a high-value mineral composition comprising potassium, calcium and iron as the main elements. The present study inferred that <em>Peperomia> <em>pellucida> would serve as a good source of protein and energy as well as micronutrients in the form of a leafy vegetable for human consumption.

  13. Reduced graphene oxide/CeO2 nanocomposite with enhanced photocatalytic performance

    Science.gov (United States)

    Kaur, Jasmeet; Anand, Kanika; Anand, Kanica; Singh, Gurpreet; Hastir, Anita; Virpal, Singh, Ravi Chand

    2015-05-01

    In this work, reduced graphene oxide /cerium oxide (RGO/CeO2) nanocomposite was synthesized by in situ reduction of cerium nitrate Ce(NO3)3.6H2O in the presence of graphene oxide by hydrazine hydrate (N2H4.H2O). The intrinsic characteristics of as-prepared nanocomposite were studied using powder x-ray diffraction (XRD), Raman spectroscopy and field-emission scanning electron microscopy (FESEM). The photocatalytic degradation of methylene blue (MB) was employed as a model reaction to evaluate the photocatalytic activity of the RGO/CeO2 nanocomposite. The as-obtained RGO/CeO2 nanocomposite displays a significantly enhanced photocatalytic degradation of MB dye in comparison with bare CeO2 nanoparticles under sunlight irradiation, which can be attributed to the improved separation of electron-hole pairs and enhanced adsorption performance due to presence of RGO.

  14. Preparation and performance of CeO2 hollow spheres and nanoparticles

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wenwen; CHEN Donghui

    2016-01-01

    CeO2 hollow spheres were synthesized by polystryrene sphere (PS) templates and CeO2 nanoparticles were prepared by a facile method. The as-obtained products were characterized by scanning electron microscopy (SEM), N2 adsorption-desorption, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and UV-vis diffuse reflectance spectra. The results showed that the structure of the obtained CeO2 hollow spheres was hollow microsphere with a diameter of 380 nm and the average particle size of CeO2 nanoparticles was about 1700 nm. The two samples' Brunauer-Emmett-Teller (BET) surface area was 67.1 and 37.2 m2/g. The CeO2 hollow spheres had a better performance than nanoparticles at UV-shielding because of higher surface area and the structure of hollow sphere.

  15. Self-template hydrothermal synthesis of CeO2 hollow nanospheres

    International Nuclear Information System (INIS)

    CeO2 hollow nanospheres were synthesized by a low-cost and environmentally benign one-pot hydrothermal route. Templates, surfactants, or other auxiliaries were not used in the route. X-ray diffraction, transmission electron microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, high-resolution transmission electron microscopy, and nitrogen adsorption–desorption measurements were used to characterize the products. The average diameter of hollow spheres, with shells of approximately 30 nm, was about 300 nm. The formation of these hollow spheres involved a transformation from Ce(OH)CO3 solid spheres to CeO2 hollow nanospheres. The CeO2 hollow nanospheres exhibited a higher catalytic activity on CO oxidation than CeO2 nano-octahedrons.

  16. Electrochemical determination of dopamine based on electrospun CeO2/Au composite nanofibers

    International Nuclear Information System (INIS)

    An electrochemical method for the detection of dopamine based on a glass carbon electrode modified with electrospun CeO2/Au composite nanofibers was investigated in this article. The CeO2/Au composite nanofibers were prepared by the electrospinning technique and then annealed in air. The CeO2/Au composite nanofibers were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) measurements. Cyclic voltammetry (CV) showed that the electrospun CeO2/Au composite nanofibers modified carbon glass electrode exhibited an excellent electrocatalytic response to the dopamine (DA). The detection limit (S/N = 3) was as low as 0.056 μM and the sensitivity could reach 127 μA mM−1 cm−2. All these demonstrated that the electrospun CeO2/Au composite nanofibers were good electrocatalyst for the oxidation of dopamine

  17. Thermal Dihydrogen Activation by a Closed-Shell AuCeO2(+) Cluster.

    Science.gov (United States)

    Meng, Jing-Heng; He, Sheng-Gui

    2014-11-01

    Laser-ablation-generated AuCeO2(+) and CeO2(+) oxide clusters were mass-selected using a quadrupole mass filter and reacted with H2 in an ion trap reactor at ambient conditions. The reactions were characterized by mass spectrometry and density functional theory calculations. The gold-cerium bimetallic oxide cluster AuCeO2(+) is more reactive in H2 activation than the pure cerium oxide cluster CeO2(+). The gold atom is the active adsorption site and facilitates the heterolytic cleavage of H2 in collaboration with the separated O(2-) ion of the CeO2 support. To the best of our knowledge, this is the first example of thermal H2 activation by a closed-shell atomic cluster, which provides molecular-level insights into the single gold atom catalysis over metal oxide supports. PMID:26278765

  18. Short-Range Order in Liquid Al-Cu-Ni-Ce Alloy

    Institute of Scientific and Technical Information of China (English)

    孙民华; 边秀房

    2002-01-01

    The liquid and amorphous structures of Al85Ni10Ce5 and Al85Cu5Ni5Ce5 alloy were studied by X-ray diffraction. The position of the first peak shifts to bigger Q-values as the concentration of Cu increases. Gaussian decomposition of first peak in radical distribution function (RDF) was applied to Al-Ni(Cu)-Ce system. The bond lengths of Al-Al, Al-TM(Transition metal) and TM-TM increase with the substitution of Ni by Cu. Viscosity measurement shows that viscosity of Al-Ni-Ce alloy increases faster than that of Al-Ni-Cu-Ce alloy. The addition of Cu can decrease the interaction between atoms, so it is unfavorable to Al-based glass formability.

  19. Synthesis of Mn-doped CeO2 nanorods and their application as humidity sensors

    Indian Academy of Sciences (India)

    C H Hu; C H Xia; F Wang; M Zhou; P F Yin; X Y Han

    2011-08-01

    Mn-doped CeO2 nanorods have been prepared from CeO2 particles through a facile compositehydroxide-mediated (CHM) approach. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The analysis from the X-ray photoelectron spectroscopy indicates that the manganese doped in CeO2 exists as Mn4+. The responses to humidity for static and dynamic testing proved dopingMn into CeO2 can improve the humidity sensitivity. For the sample with Mn% about 1.22, the resistance changes from 375.3 to 2.7M as the relative humidity (RH) increases from 25 to 90%, indicating promising applications of the Mn-doped CeO2 nanorods in environmental monitoring.

  20. Effect of Ce3+ on membrane permeability of Escherichia coli cell

    Institute of Scientific and Technical Information of China (English)

    CHEN Aimei; SHI Qingshan; OUYANG Yousheng; CHEN Yiben

    2012-01-01

    This study aimed to delineate the antibacterial mechanism of rare-earth ion Ce3+ to the target organism Escherichia coli cell,and the most important purpose was to identify its biological effect of increasing the E.coli cell membrane permeability.The antibacterial activities of Ce3+ to E.coli cells were tested,and then the permeability of outer membrane (OM) and inner membrane (IM) were studied by N-phenyl-1-naphthylamine (NPN) and o-nitrophenyl-β-D-galactopyranoside (ONPG) methods separately.Through these experiments we concluded that the E.coli cells grown to log phage were more sensitive to Ce3+ than the ones not at this stage; the structure of membrane was destroyed and the permeability of both OM and IM was obviously increased by Ce3+; there should be certain interactions between Ce3+ and some proteins inside the cell,which impeded the physiological activities of bacteria.

  1. THE REVIEW OF PROBLEM AND THE ADVANTAGE OF INVESTING IN A PROJECT OBTAINING CE MARK

    Directory of Open Access Journals (Sweden)

    Katarina Kanjevac Milovanovic

    2013-09-01

    Full Text Available There is no competitive national economy without discharging the most important condition and those are competitive products that satisfy technical and safety mark etrequires, that is, products with the CE mark. The aim of this work is to highlight the problems and the main limitations in obtainin g the CE mark , and the benefits and justification of investment in the CE mark. The research was conducted in three directions. First he research conducted the quality of the existing infrastructure in Serbia. Then we went on to research many problems in obtaining the CE mark. To test the feasibility of investing in obtaining the CE mark was used cost benefit analysis. Based on the results, the results presented in this work strongly suggests that investment in obtaining resources for labeling of products h as a high rate of return.

  2. The effect of some factors on Ms and SME in Ce-TZP ceramics

    International Nuclear Information System (INIS)

    As known to all, shape memory behaviour has been observed in a variety of metallic alloys. This phenomenon, however, is not only observed in that field but also in other materials recently, such as in polymers, intermetallic compounds and ceramics, especially in zirconia ceramics. Swain observed the shape recovery of a bent magnesia-partially-stabilized zirconia (Mg-PSZ) bar upon heating above a certain temperature. The maximum deflection which was nearly completely recovered on heating is about 300 μm. Chen et al., investigated the pseudoelasticity and shape memory effect (SME) in ceria-stabilized tetragonal zirconia polycrystals (Ce-TZP) containing 12 mol% CeO2. Wang et al., also observed the SME in Ce-TZP containing 10 mol% CeO2. In this paper, the authors would like to introduce some of results conducted recently in our group on SME in Ce-TZP ceramics

  3. Experimental evidence of a strongly reduced orbital moment in CeRh3B2

    International Nuclear Information System (INIS)

    Magnetic circular X-ray dichroism (MCXD) studies at the Ce-L2,3 and M4,5 absorption edges in the CeRh3B2 and CeFe2 compounds are presented. Experiments at the L2,3 edges allow to get information on the 5d magnetism whereas the M4,5 edges witness the behavior of the 4f electrons. It will be shown that in CeRh3B2, the properties of the 4f orbitals are between localization and intermediate valence. Values of the magnetic moment on the Ce atom can be estimated from MCXD measurements. The 4f orbital magnetic moment is found to be strongly reduced by crystal field effects as compared to the value expected for fully localized electrons. ((orig.))

  4. Synthesis and characterization of BaCeO3 nanocrystals viasolvothermal-based method

    Institute of Scientific and Technical Information of China (English)

    XU Chao; ZHU Junwu; YANG Xujie; LU Lude; WANG Xin

    2008-01-01

    A facile approach to preparing well-dispersed nanocrystals of BaCeO3 was developed by a combination of solvothermal and annealing processes. The precursor consisted of amorphous BaCO3 and CeO2, and the conversion of the precursor to crystalline BaCeO3 nanocrystals occurred upon heat treatment at a relatively low temperature. The as-processed BaCeO3 had an orthorhombic structure and the average size of such crystals was approximately 80 nm. The obtained products were characterized by Fourier Transform Infrared (FT-IR), X-Ray Diffraction (XRD), Laser Raman Spectroscopy (LRS), Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Spectrometry (EDS), and Transmission Electron Microscopy (TEM). This preparation process could also be used to synthesize doped barium cerate complex oxides BaCe0.95M0.05O3-d (M=Y, Nd, Gd, and Sm).

  5. Photoluminescence properties of color-tunable KLaSiO4:Ce3+,Mn2+phosphors

    Institute of Scientific and Technical Information of China (English)

    常文瑞; 王丹; 朋兴平; 王育华; 胡龄之; 王静

    2015-01-01

    A series of color-tunable KLaSiO4:Ce3+,Mn2+phosphors were successfully prepared and the luminescent properties were investigated. Upon excitation at 290 nm, the emission spectra of KLaSiO4:Ce3+,Mn2+phosphors included a blue emission band and a red emission band. Increasing the doping concentration of Mn2+ions, the red emission was strengthened considerably, and the blue emission of Ce3+ was reduced, owing to the efficient energy transfer. The composition optimized KLa0.96SiO4:0.02Ce3+,0.02Mn2+sample exhibited the white light emission brightly with the chromaticity coordinates of (0.331, 0.337). Therefore, KLaSiO4:Ce3+, Mn2+could be used as a white phosphor candidate for white light-emitting diodes devices.

  6. Preparation and Characterization of Graphite Powder Covered with CeO2

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    In order to improve the wetting properties of graphite with Al melt and reduce the oxidation of the graphite, by which the segregation of components during the liquid-stir-casting process could be prevented. In this paper, a uniform thin nano-film of CeO2, about 20 nm thick, was successfully prepared onto graphite powder surface by heterogeneous nucleation process. The results show that an obvious chemical reaction did exit between CeO2 film and graphite with the formation of Ce-O-C bond, leading to a shift of the binding energy of C and Ce. The cover with CeO2 film illustrates a distinct change of surface state of graphite with a decrease of angle of contact.

  7. White light generation in Ce3+-Tb3+-Sm3+ codoped oxyfluoroborate glasses

    International Nuclear Information System (INIS)

    Ce3+, Tb3+and Sm3+ oxyfluoroborate glasses were prepared and characterized using absorption, photoluminescence and time decay spectral analysis respectively. The decrease of emission peak intensity and lifetime values of Ce3+ ions are observed by introducing Tb3+ and Sm3+ into glass. This is due to an efficient energy transfer from Ce3+ to Tb3+, Sm3+; Tb3+ to Sm3+ and cross-relaxation channels. Further, the important characteristic parameters of white light emitting materials viz., energy transfer efficiency, chromaticity color coordinates, correlated color temperature and color purity are evaluated. - Highlights: • The energy transfer from Ce3+ to Tb3+; Sm3+ and Tb3+ to Sm3+ is studied. • CIE color coordinates fall in blue, green and white regions. • Ce3+-Tb3+-Sm3+ doped glasses exhibit white light emission under 312 nm excitation

  8. The magnetic properties of Ce/Pd surface alloys investigated using DFT

    KAUST Repository

    Shuttleworth, I.G.

    2014-06-01

    The surface alloys that form between Ce and Pd(1 1 1), Pd(1 0 0) and both unreconstructed and missing-row type Pd(1 1 0) at low Ce coverage ( θCe=19ML) have shown permanent magnetism that is mediated in part by an RKKY-like delocalized Ce 6s-Pd 5s interaction. The Pd 4d states are significantly affected by alloying and their behavior cannot be explained by a purely spin-dependent Hamiltonian. Experimental observations of changes to the Pd 4d states are explained and the implications of Ce/Pd magnetism in reforming catalysis are discussed. © 2014 Elsevier B.V. All rights reserved.

  9. Caracterização pós-colheita de figos (Ficus carica L. produzidos sob diferentes condições de cultivo na Chapada do Apodi – CE.

    Directory of Open Access Journals (Sweden)

    Raniely Nayanne da Silva Freitas

    2015-03-01

    Full Text Available A produção de figos para consumo in natura é limitada pelas chuvas, que causam elevadas perdas por podridão, o que pode dificultar o seu cultivo durante a estação chuvosa local (fevereiro a maio, época em que a fruta atinge a sua maior cotação. Essa dificuldade poderá ser contornada com o uso de ambiente protegido. Objetivou-se com o presente trabalho, realizar a caracterização da qualidade pós-colheita de figos produzidos sob cultivo protegido e a céu aberto na Chapada do Apodi- CE. Os frutos utilizados neste experimento foram colhidos em pomar experimental da Unidade de Ensino e Pesquisa (UEPE, pertencente ao Instituto Federal de Educação, Ciência e Tecnologia do Ceará (IFCE, localizada na Chapada do Apodi em Limoeiro do Norte – Ceará, onde os mesmos foram cultivados a céu aberto e em estufa.  Foram realizadas as seguintes análises: diâmetro do fruto, peso do fruto, firmeza da polpa, sólidos solúveis (SS, acidez titulável(AT, pH, RATIO e vitamina C. De acordo com os parâmetros analisados, os figos cultivados em estufa apresentaram melhores atributos físico-químicos em relação aos cultivados em céu aberto, concluindo-se que, o tipo de cultivo influencia na qualidade pós-colheita do fruto.

  10. Ultrasound-Assisted Extraction of Syringin from the Bark of <em>Ilex em>rotunda> Thumb Using Response Surface Methodology

    OpenAIRE

    Hui Wang; Li-Chun Zhao; Wei Li; Xin Deng; Xiang-Hua Xia; Jian Liang; Geng-Liang Yang; Ying He

    2012-01-01

    In this work, a rapid extraction method based on ultrasound-assisted extraction (UAE) of syringin from the bark of <em>Ilex rotunda em>Thumb using response surface methodology (RSM) is described. The syringin was analyzed and quantified by high performance liquid chromatography coupled with UV detection (HPLC-UV). The extraction solvent, extraction temperature and extraction time, the three main factors for UAE, were optimized with Box-Behnken design (BBD) to obtain the highest ...

  11. Chemical Composition, Antimicrobial and Antitumor Activities of the Essential Oils and Crude Extracts of<em> Euphorbiaem>> macrorrhizaem>

    Directory of Open Access Journals (Sweden)

    Haji Akber Aisa

    2012-05-01

    Full Text Available The present study aimed to examine the chemical composition and biological activity of essential oils extracted from <em>Euphorbia macrorrhizaem> collected from Northwest China. The major constituents of the essential oils of aerial parts and roots of <em>E. macrorrhizaem> are acorenone B (16.72% and 25.80%, (+-cycloisosativene (14.94% and 12.40%, 3a-hydroxy-5b-androstane (10.62% and 5.52%, copaene (7.37% and 6.29%, l-calamenene (4.13% and 4.65% and β-cedrene (8.40% and 7.98%, respectively. The minor components of them are thymene, γ-terpinene, thymecamphor, α-cedrene, zingiberene, trans-caryophyllene, β-chamigrene, curcumene, pentadecane, (−-α-muurolene, cuparene, γ-cadinene, (<em>Z>-3-heptadecene, 1,3,7,7-tetramethyl-2-oxabicyclo(4.4.0dec-5-en-4-one, hexahydrofarnesyl acetone, γ-elixene and palmitinic acid. The antimicrobial and antitumor activitiy of the <em>E. macrorrhizaem> essential oil against <em>Staphyloccocus aureusem>, <em>Escherichia coliem>, <em>Canidia Albicansem> and Caco-2 cells were evaluated. Among all the tested microorganisms and Caco-2 cells, the essential oils showed the strongest inhibitory effect on <em>Staphyloccocus aureus em>(MIC = 2.8 μg/mL and Caco-2 cell (IC50 = 11.86 μg/mL, whereas no effect on <em>Escherichia coliem> and <em>Candida em>albicans>. The data of this study suggested that the <em>E. macrorrhizaem> essential oils have great potential as a natural medicine for microbial infections and cancers.

  12. Effects of <em>Citrus aurantiumem> (Bitter Orange Fruit Extracts and <em>p>-Synephrine on Metabolic Fluxes in the Rat Liver

    Directory of Open Access Journals (Sweden)

    Rosane Marina Peralta

    2012-05-01

    Full Text Available The fruit extracts of <em>Citrus aurantiumem> (bitter orange are traditionally used as weight-loss products and as appetite supressants. An important fruit component is <em>p>-synephrine, which is structurally similar to the adrenergic agents. Weight-loss and adrenergic actions are always related to metabolic changes and this work was designed to investigate a possible action of the <em>C. aurantiumem> extract on liver metabolism. The isolated perfused rat liver was used to measure catabolic and anabolic pathways, including oxygen uptake and perfusion pressure. The <em>C. aurantiumem> extract and <em>p>-synephrine increased glycogenolysis, glycolysis, oxygen uptake and perfusion pressure. These changes were partly sensitive to a- and b-adrenergic antagonists. <em>p>-Synephrine (200 mM produced an increase in glucose output that was only 15% smaller than the increment caused by the extract containing 196 mM <em>p>-synephrine. At low concentrations the <em>C. aurantiumem> extract tended to increase gluconeogenesis, but at high concentrations it was inhibitory, opposite to what happened with <em>p>-synephrine. The action of the <em>C. aurantiumem> extract on liver metabolism is similar to the well known actions of adrenergic agents and can be partly attributed to its content in <em>p>-synephrine. Many of these actions are catabolic and compatible with the weight-loss effects usually attributed to <em>C. aurantiumem>.

  13. Evidence for strong f -d hybridization in the intermetallic ferromagnet CePdIn2

    Science.gov (United States)

    Carleschi, E.; Doyle, B. P.; Snyman, J. L.; Magnano, E.; Nappini, S.; Pis, I.; Bondino, F.; Peratheepan, P.; Strydom, A. M.

    2015-12-01

    We have investigated the contribution of Ce 4 f states to the electronic structure of the intermetallic ferromagnet CePdIn2 by means of x-ray absorption spectroscopy and resonant and nonresonant photoemission spectroscopy. The line shape of the Ce M5 ,4 absorption edge reveals the localized nature of the 4 f states, and is consistent with a predominantly 3+ ionic state for Ce ions. Fitting of the Ce 3 d core level gives a Ce 4 f occupation number at room temperature of 0.92, which is in good agreement with the Ce effective magnetic moment of 2.20 μB (corresponding to ˜87 % of the free-electron moment) as calculated from the inverse magnetic susceptibility. Moreover, the hybridization strength between 4 f and conduction electrons is found to be ˜180 meV, revealing that CePdIn2 is a strongly hybridized system. This is consistent with the results from the analysis of the resonant valence band photoemission measurements at both the N5 ,4 and the M5 edges, showing that the Ce 4 f states are composed of the features predicted by the single-impurity Anderson model, i.e., a broad 4 f0 peak centered at 1.9 eV and two 4 f1 spin-orbit states much closer to the Fermi level. The same spectra also show that the Ce 4 f resonant spectral weight extends over a wide binding energy range, overlapping with that presumably occupied by the Pd 4 d ligand states. This energy overlap is interpreted as a signature of the strong hybridization governing the system, which could possibly favor the emergence of long-range ferromagnetism through the indirect exchange between localized 4 f states mediated by highly dispersive d electrons.

  14. Synthesis and properties of electrodeposited Ni–B–CeO2 composite coatings

    International Nuclear Information System (INIS)

    Highlights: • Alteration of metallic luster, chemical composition and crystal structure. • Remarkable improvement in mechanical properties. • A decent improvement in corrosion behavior. - Abstract: Ni–B coatings are extremely hard and wear resistant with decent anticorrosion properties which make them suitable for automotive, aerospace, petrochemical, plastic, optics, nuclear, electronics, computer, textile, paper, food and printing industries. However, further improvement in properties is essential to address more challenging requirements and new developments. In the present study, Ni–B and novel Ni–B–CeO2 composite coatings were electrodeposited (ED) on mild steel substrates using dimethylamine borane (DMAB) as a reducing agent. A comparison of properties of Ni–B and Ni–B–CeO2 coatings is presented to elucidate the useful role of CeO2 addition. The structural analyses indicate that Ni–B coatings are amorphous in their as deposited state. However, addition of CeO2 into Ni–B matrix considerably improves the crystallinity of the deposit. The surface morphology study reveals the formation of uniform, dense and fine-grained deposit in both Ni–B and Ni–B–CeO2 composite coatings. However, Ni–B–CeO2 composite coatings exhibit high surface roughness. The nano mechanical properties show that the addition of CeO2 particles into Ni–B matrix results in remarkable improvement in mechanical properties (hardness and modulus of elasticity) which may be attributed to dispersion hardening of Ni–B matrix by CeO2 particles. The electrochemical polarization tests confirm that the addition of CeO2 improves the corrosion resistance of Ni–B coatings. This improvement in corrosion behavior may be ascribed to the reduction in active area of Ni–B coatings by the presence of inactive CeO2 particles into Ni–B matrix

  15. Luminescence properties and electronic structure of Ce3+-doped gadolinium aluminum garnet

    International Nuclear Information System (INIS)

    Highlights: • The luminescence properties of Ce3+ ions in (Y, Gd)3Al5O12 are analyzed. • The Gd3+ → Y3+ substitution leads to increasing of Ce3+ noncubic crystal field splitting parameter. • The excitation spectra for the Ce3+ emission in GdAG contain bands at 6.67, 7.75, and 9.76 eV. • These features are due to the Ce3+-bound exciton formation and O 2p → Al 3s, 3p transitions. • Contributions from Al atoms to the conduction-band density of states are quite essential. - Abstract: Yttrium-gadolinium aluminum garnets (YGdAG) doped with Ce3+ ions have been prepared by co-precipitation method. The luminescent properties of Ce3+ ions in Gd3(1−x)Ce3xAl5O12 (x = 0.01) have been studied upon excitation in the 2–20 eV region. The substitution of Gd3+ for Y3+ in the garnet structure results in broadening the emission band and shifting its maximum towards the longer wavelengths. It was found that in addition to the 4f → 5d excitation bands of Ce3+ ions, the excitation spectra for the Ce3+ emission contain bands at 6.67, 7.75, and 9.76 eV. These bands are attributed to the Ce3+-bound exciton formation and O 2p → Al 3s, 3p transitions, respectively. Although gadolinium states dominate near the bottom of the conduction band of Gd3Al5O12, contributions from Altetr and Aloct atoms to the conduction-band density of states are evaluated as quite essential

  16. High-pressure transformations of cerium(III)orthovanadate(V), CeVO4

    International Nuclear Information System (INIS)

    The polymorphism of CeVO4 was investigated at high pressures and temperatures in a Belt-type high-pressure apparatus. In addition to the normal-pressure modification CeVO4-I with zircon-type structure two high-pressure modifications have been found, viz. monazite-type CeVO4-II and scheelite-type CeVO4-III. CeVO4-II is stable between 1 bar and 30 kbar at 1300deg C. Its region of existence decreases rapidly at lower temperatures. From the observed p,T-relations for the I-II and I-III transformations a triple point CeVO4-I,II,III at about 27 kbar, 500deg C can be estimated. For kinetic reasons, however, the experimental determination of phase relations becomes difficult at temperatures below 600deg C. The crystal structures of CeVO4-I and -II have been refined from single-crystal data. Crystallographic data for the three modifications are given and discussed (CeVO4-I: I41/amd, a=7.383(1) A, c=6.485(1) A, Z=4; CeVO4-II: P21/n, a=7.003(1) A, b=7.227(1) A, c=6.685(1) A, β=105.13(1)deg, Z=4; CeVO4-III: I41/a, a=5.1645(2) A, c=11.8482(7) A, Z=4). (orig.)

  17. Investigation of phase equilibria in the quaternary Ce-Mn-In-Ge system and isothermal sections of the boundary ternary systems at 800 °C

    International Nuclear Information System (INIS)

    Highlights: • Ce-Mn-In, Mn-In-Ge, Ce-In-Ge, and Ce-Mn-Ge systems at 800 °C were examined. • Ce3Mn2Ge3 and Ce43Mn18Ge39 are new high-temperature phases with close composition. • Two new quaternary phases, Ce4Mn2InGe4 and Ce2Mn2InGe2, were discovered. - Abstract: Part of the quaternary Ce-Mn-In-Ge phase diagram has been examined through powder X-ray diffraction and energy-dispersive X-ray analysis. Two new quaternary (Ce4Mn2InGe4 and Ce2Mn2InGe2) and two ternary (Ce3Mn2Ge3 and Ce43Mn18Ge39) phases were found. The isothermal sections of the boundary ternary systems (Ce-Mn-In, Mn-In-Ge, Ce-In-Ge, and Ce-Mn-Ge) were determined at 800 °C. Among these, the Ce-Mn-Ge system deserves particular attention because the phase equilibria are complex. Relative to the previously reported phase diagram evaluated at a lower temperature (400 °C), three ternary phases (CeMn2Ge2, Ce2MnGe6, and CeMnGe) persist, Ce2MnGe5 does not form, and two new phases with very close composition (Ce3Mn2Ge3 and Ce43Mn18Ge39) appear at 800 °C. Ce3Mn2Ge3 (orthorhombic Hf3Ni2Si3-type) has a small homogeneity range (2%) deviating from the ideal composition, whereas Ce43Mn18Ge39 (tetragonal La2+xMnGe2+y-type) has negligible homogeneity. Magnetic measurements on Ce4Mn2InGe4 suggest ferromagnetic behaviour

  18. Antioxidant Profile of <em>Trifolium pratenseem> L.

    Directory of Open Access Journals (Sweden)

    Heidy Schwartsova

    2012-09-01

    Full Text Available In order to examine the antioxidant properties of five different extracts of <em>Trifolium pratenseem> L. (Leguminosae leaves, various assays which measure free radical scavenging ability were carried out: 1,1-diphenyl-2-picrylhydrazyl, hydroxyl, superoxide anion and nitric oxide radical scavenger capacity tests and lipid peroxidation assay. In all of the tests, only the H2O and (to some extent the EtOAc extracts showed a potent antioxidant effect compared with BHT and BHA, well-known synthetic antioxidants. In addition, <em>in vivo em>experiments were conducted with antioxidant systems (activities of GSHPx, GSHR, Px, CAT, XOD, GSH content and intensity of LPx in liver homogenate and blood of mice after their treatment with extracts of <em>T. pratenseem> leaves, or in combination with CCl4. Besides, in the extracts examined the total phenolic and flavonoid amounts were also determined, together with presence of the selected flavonoids: quercetin, luteolin, apigenin, naringenin and kaempferol, which were studied using a HPLC-DAD technique. HPLC-DAD analysis showed a noticeable content of natural products according to which the examined <em>Trifolium pratenseem> species could well be regarded as a promising new source of bioactive natural compounds, which can be used both as a food supplement and a remedy.

  19. Casca de soja em dietas para coelhos em crescimento

    Directory of Open Access Journals (Sweden)

    Ana Carolina Kohlrausch Klinger

    2015-01-01

    Full Text Available O presente trabalho teve como objetivo avaliar efeitos da inclusão de casca de soja em substituição ao feno de alfafa sobre o desempenho, características da carcaça e trato gastrointestinal e parâmetros bioquímicos de coelhos em fase de crescimento. Foram utilizados 30 coelhos da raça Nova Zelândia Branca, divididos igualmente em três tratamentos, compostos pela dieta experimental padrão (sem inclusão de casca de soja; e pelas dietas com 50% e 100% de substituição de alfafa por casca de soja nas respectivas rações experimentais. Concluiu-se que a casca de soja pode ser incluída em dietas para coelhos em crescimento, em substituição ao feno de alfafa em até 100% sem causar danos no desempenho nas características de carcaça e do trato gastrointestinal e parâmetros bioquímicos dos animais, durante a fase de crescimento. Porém, a utilização deste co-produto exige a necessidade de estudos mais aprofundados em virtude da escassez de dados.

  20. Consumo alimentar de mulheres sobreviventes de câncer de mama: análise em dois períodos de tempo

    OpenAIRE

    Helena Alves de Carvalho Sampaio; Daianne Cristina Rocha; Maria Olganê Dantas Sabry; Luiz Gonzaga Porto Pinheiro

    2012-01-01

    OBJETIVO: Comparar o consumo alimentar de dois grupos de mulheres portadoras de câncer de mama atendidas em dois períodos distintos: 1999-2004 e 2005-2009. MÉTODOS: Estudo documental, com abordagem descritiva e comparativa. Foram coletados dados de identificação e de ingestão alimentar nas fichas de 154 pacientes portadoras de câncer de mama atendidas em serviços de referência de Fortaleza (CE): 66 no período de 1999-2004 e 88 no de 2005-2009. Foram considerados como integrantes do hábito os ...