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  1. Estudo e comparação de materiais eletrocatalíticos de Pd e PdBi suportados em carbono e nanotubos de carbono para posterior uso em uma célula a combustível alcalina alimentada diretamente por etanol

    OpenAIRE

    2015-01-01

    Orientador: Prof. Dr. Mauro Coelho dos Santos Dissertação (mestrado) - Universidade Federal do ABC. Programa de Pós-Graduação em Ciência e Tecnologia/Química, 2015. A reação de oxidação eletroquímica do etanol foi estudada em meio alcalino utilizando-se os eletrocatalisadores Pd e PdBi (razões atômicas 90:10, 50:50 e 70:30 em 20% de metais) suportados em carbono e nanotubos de carbono. As formulações propostas foram preparadas pelo método de redução por borohidreto de sódio. Os eletroca...

  2. Alta regio-seletividade das reações de nitração e oxidação com nitratos de acila suportados

    OpenAIRE

    Antonio Pedro de Oliveira Filho

    1995-01-01

    Resumo: Neste trabalho foi desenvolvido uma metodologia para obtenção de reações de nitrações com alta regio-seletividade, utilizando-se de nitratos de acila suportados em argila minerais, como crisotila. Ela possui cela unitária Mg3Si2O5(OH)5 e área superficial superior a 14m/g, após tratamento em solução tampão ácido acético/acetato de sódio. Reações de nitrações de alqui-benzenos, utilizando o sistema suportado, nitratos de acila/crisotila produziu na reação com o tolueno 70% de para- e 30...

  3. Estudo da preparação do catalisador Cp2ZrCl2 suportado em sílica utilizando um planejamento de experimentos Preparation conditions of Cp2ZrCl2 supported on silica using an experimental planning

    Directory of Open Access Journals (Sweden)

    Anunciata Conte

    2001-03-01

    Full Text Available O monômero eteno foi polimerizado através dos sistemas catalíticos Cp2ZrCl2/SiO2 e Cp2ZrCl2/MAO/SiO2. Foi elaborado um planejamento estatístico de experimentos a fim de se identificar as melhores condições de preparo dos catalisadores heterogêneos. As variáveis utilizadas foram a concentração de metilaluminoxano (MAO no pré-tratamento do suporte, a concentração e a temperatura de imobilização do metaloceno. Os catalisadores suportados foram analisados por espectrometria de emissão com plasma acoplado indutivamente e as resinas produzidas foram caracterizadas por cromatografia de permeação em gel (GPC e calorimetria de varredura diferencial (DSC. Foi observado que quanto maior a concentração de zircônio fixada na superfície do suporte, menor foi a atividade catalítica, na faixa de variáveis estudadas.Ethylene was polymerized with the catalytic systems Cp2ZrCl2/SiO2 and Cp2ZrCl2/MAO/SiO2. A experimental planning model was developed in order to identify the best conditions for the preparation of metallocene heterogeneous catalysts. The variables used were methylaluminoxane (MAO concentration of the support treatment, concentration and temperature of metallocene immobilization. The supported catalysts were analyzed by inductively coupled plasma emission spectometry and the polyethylene (PE produced was characterized by gel permeation calorimetry (GPC and differential scanning calorimetry (DSC. It was observed that the higher the zirconium concentration fixed on the support surface, the lower the catalyst activity, in the studied variables range.

  4. Modelo para Construção de Base de Conhecimentos sobre Projetos Suportado por Ferramentas Colaborativas

    Directory of Open Access Journals (Sweden)

    Douglas Paulesky Juliani

    2013-01-01

    Full Text Available A utilização de ferramentas de colaboração para o gerenciamento de bases de conhecimento permite que as organizações possam armazenar e disseminar o conhecimento produzido nos projetos de maneira efetiva Aliar modernas soluções de tecnologia de informação a conceitos de gestão do conhecimento e gerenciamento de projetos, beneficiando com a manutenção e utilização da memória organizacional através da utilização de modelos especificados possibilitaa obtenção de vantagens competitivas.Este artigo tem por objetivo apresentar um modelo para a construção de uma base de conhecimentos, com basenas lições aprendidas no gerenciamento de projetos baseado no guia PMBOK (Um Guia do Conhecimento em Gerenciamento de Projetos, suportado por ferramentas colaborativas e fundamentos de gestão do conhecimento.DOI:10.5585/gep.v3i3.128

  5. 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)

  6. Decomposição do metanol sobre catalisadores de paladio suportados

    OpenAIRE

    Alberto Magno Menezes Vieira

    1995-01-01

    Resumo: Neste trabalho foi feito um estudo quantitativo da reação de decomposição do metanol utilizando os catalisadores Pd/Al2O3C5/95),Pd/La203(5/95) e Pd-Cu/La203 (5% de Pd+Cu, razão molar Pd/Cu = 1/1), visando contribuir para um melhor entendimentodo mecanismoda reação de síntesedo metanol. O método de preparação dos catalisadores utilizado foi o da impregnação semi-úmida. Os catalisadores foram caracterizados através dos métodos: Absorção atômica, método de BET, redução à temperatura p...

  7. Imobilização de líquidos iônicos formados pelo cátion 1-metil-3-(3-trimetoxissililpropil) imidazólio em MCM-41 por ancoragem e em xerogel para uso em captura e conversão de CO2

    OpenAIRE

    Aquino, Aline Scaramuzza

    2014-01-01

    O estudo de novos materiais para a captura de CO2 aponta como uma opção, o uso de líquidos iônicos como solventes para absorção, pois são compostos nos quais o CO2 apresenta uma solubilidade preferencial. Imobilizar líquidos iônicos em materiais mesoporosos pode ser uma combinação mais vantajosa na captura seletiva. Desta maneira, o objetivo desta tese de doutorado consiste em sintetizar e caracterizar estruturas de líquidos iônicos suportados em materiais mesoporosos, verificar a capacidade ...

  8. Wet chemical synthesis of nickel supported on alumina catalysts; Sintese de catalisadores de niquel suportado em alumina por via umida

    Energy Technology Data Exchange (ETDEWEB)

    Freire, Ranny Rodrigues; Costa, Talita Kenya Oliveira; Morais, Ana Carla da Fonseca Ferreira; Costa, Ana Cristina Figueiredo de Melo; Freitas, Normanda Lino de, E-mail: normanda@ufcg.edu.br [Universidade Federal de Campina Grande (UFCG), PB (Brazil)

    2016-07-01

    Heterogenic catalysts are those found to be in a different phase on the reaction when compared to the reactants and products. Preferred when compared to homogeneous catalysts due to the easiness on which the separation is processed. The objective of this study is to obtain and characterize Alumina based catalysts impregnated with Nickel (Al{sub 2}O{sub 3}), by wet impregnation. The alumina was synthesized by combustion reaction. Before and after the impregnation the catalysts were characterized by X-ray diffraction (XRD), granulometric analysis, the textural analysis will be held by nitrogen adsorption (BET), energy-dispersive X-ray spectroscopy (EDX) and scanning electron microscopy (SEM). The results show a presence of a stable crystalline phase of Al2O3 in all the studied samples and after the impregnation the second phase formed was of NiO and NiAl{sub 2}O{sub 4}. The Al{sub 2}O{sub 3} e Ni/Al{sub 2}O{sub 3} catalysts resulted in clusters with a medium diameter of 18.9 and 14.2 μm, respectively. The catalysts show a medium-pore characteristic (medium pore diameter between 2 and 50 nm), the superficial area to Al{sub 2}O{sub 3} and Ni/Al{sub 2}O{sub 3} catalysts were 8.69 m{sup 2}/g and 5.56 m{sup 2}/g, respectively. (author)

  9. Efeito de ZN, Cd e Cu no comportamento de fungos ectomicorrízicos em meio de cultura

    Directory of Open Access Journals (Sweden)

    P. H. Grazziotti

    2001-12-01

    Full Text Available Os fungos ectomicorrízicos são capazes de tolerar concentrações de metais pesados tóxicas às plantas hospedeiras, apesar de serem adversamente influenciados pelo excesso de alguns metais. Avaliou-se o crescimento de um isolado de Pisolithus tinctorius e outro de Suillus bovinus em meio de cultura líquido com doses crescentes de sais de Zn, Cu ou Cd adicionados individualmente em frascos de 125 mL que continham 50 mL de meio Mellin-Norkrans modificado (MNM, em pH 4,8. Os fungos cresceram por 20 dias em câmara de crescimento a 28ºC. O crescimento dos fungos foi inibido com a elevação das concentrações dos metais, porém de forma diferenciada. As concentrações suficientes para inibir 50% do crescimento foram de 2,71 x 10-3 mol L-1 de Zn, 1,18 x 10-3 mol L-1 de Cu e 12,2 x 10-6 mol L-1 de Cd, para o P. tinctorius, e de 2,15 x 10-3 mol L-1 de Zn, 0,12 x 10-3 mol L-1 de Cu e 7,2 x 10-6 mol L-1 de Cd, para o S. bovinus. O efeito inibitório dos metais sobre o crescimento dos fungos seguiu a seguinte ordem decrescente: Cd > Cu > Zn. O isolado de S. bovinus apresentou tolerância ao Zn similar à observada para o P. tinctorius, mas foi menos tolerante que este em relação aos outros dois metais. O crescimento de P. tinctorius foi favorecido por pequena dose de Cu. A produção de pigmentos extracelulares nestes isolados foi estimulada por todos os metais estudados. O P. tinctorius, o mais tolerante, produziu mais pigmentos extracelulares por grama de micélio, o que sugere a relação positiva entre a capacidade de produção de pigmentos e a tolerância aos metais.

  10. Mobilidade de oxigênio intersticial em cerâmicas SmBa2Cu3O7-delta Mobility of interstitial oxygen in SmBa2Cu3O7-delta ceramics

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    R. M. Nascimento

    2005-09-01

    Full Text Available Desde a descoberta dos supercondutores com alta temperatura crítica, vários trabalhos têm sido efetuados sobre as diferentes propriedades destes materiais. As cerâmicas YBa2Cu3O7-delta mostraram que têm suas propriedades supercondutoras fortemente afetadas pela quantidade de oxigênio. Mais recentemente, medidas de relaxação anelástica em La2CuO4+delta mostraram que a remoção deste elemento pode ser relacionada com dois eventos. Um deles é o decréscimo na mobilidade entre dois planos adjacentes CuO e o outro, é o aumento no número de padrões de mobilidade para os octaedros CuO6. Para SmBa2Cu3O7 (SBCO, a possibilidade de uma estequiometria de oxigênio variável e sua alta mobilidade nos planos CuOx, dá origem a um diagrama de fases bastante rico. Neste trabalho, são reportadas medidas de espectroscopia anelástica em amostras de SBCO, que mostram um pico de relaxação termicamente ativado, que foi atribuído aos saltos de átomos de oxigênio nas posições O1 e O5 da rede.Since the discovery of the high-Tc superconductors, several works have been made about the different properties of these materials. The YBa2Cu3O7-delta ceramic showed to have its superconducting properties strongly affected by the oxygen content. More recently, anelastic relaxation measurements in La2CuO4+delta, showed that the removal of this element can be related to two events. One is the decrease in mobility between two adjacent CuO planes, and the other is the increase in the number of tilting patterns of the CuO6 octahedra. For SmBa2Cu3O7 (SBCO, the possibility of variable stoichiometry and the high mobility of oxygen in the CuOx planes give rise to a rich phase diagram. In this paper, anelastic spectroscopy measurements are reported in SBCO samples which shown a thermally activated relaxation peak that was attributed to the jumps of the oxygen atoms in the inter-chains O1 and O5 of the lattice.

  11. Cu e Zn na cultura do sorgo cultivado em três classes de solos: II. Composição mineral Cu e Zn in sorghum cultivated in three soil classes: II. Mineral composition

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    Hemmannuella C. Santos

    2009-04-01

    Full Text Available Os micronutrientes Cu e Zn possuem importantes funções no metabolismo vegetal, mas, infelizmente, estudos sobre as exigências em micronutrientes para a cultura do sorgo, são escassos. Com o objetivo de avaliar o efeito da aplicação de Cu e Zn nos atributos nutricionais da cultura do sorgo e no teor de proteína bruta, realizou-se um experimento em ambiente protegido e se utilizou delineamento em blocos casualizados, com a combinação de cinco doses de Cu (0, 0,26, 0,90, 1,54 e 1,80 mg kg-1 e cinco doses de Zn (0, 0,32, 1,1, 1,88 e 2,2 mg kg-1, combinadas na matriz Composto Central de Box, perfazendo 9 tratamentos, os quais foram aplicados em três classes de solo (Latossolo, Luvissolo e Neossolo, com 3 repetições; aos 96 dias após a semeadura avaliaram-se os teores e acúmulo de nutrientes nas plantas de sorgo; a aplicação de Cu resultou em incrementos nos teores e acúmulo de N, P, K e Cu, e no teor de proteína bruta dos grãos, o mesmo não ocorrendo para o Zn. Entre os solos, o Luvissolo foi o mais responsivo à aplicação dos nutrientes.The micronutrients copper and zinc have important functions in vegeatable metabolism, but studies about micronutrient needs for sorghum are scarce. Aiming to evaluate the effect of copper and zinc application in nutritional attributes of sorghum an experiment was carried out in a randomized block experimental design with a combination of five doses of copper (0, 0.26, 0.90, 1.54 and 1.80 mg kg-1 and five doses of zinc (0, 0.32, 1.1, 1.88 and 2.2 mg kg-1 combined by Box Central Composite design, resulting in nine treatments, which were applied in three soil classes (Latosol, Alfisol and Entisol, with three replications. Ninety six days after sowing, nutrients contents and accumulation and protein contents were determined. The copper application increased nitrogen, phosphorus, potassium and copper contents and crude protein content in grains, however, the same results were not observed for zinc

  12. Teores de Fe, Mn, Zn, Cu, Ni E Co em solos de referência de Pernambuco Concentrations of Fe, Mn, Zn, Cu, Ni and Co in benchmark soils of Pernambuco, Brazil

    Directory of Open Access Journals (Sweden)

    Caroline Miranda Biondi

    2011-06-01

    Full Text Available Metais pesados formam um grupo de elementos com particularidades relevantes e de ocorrência natural no ambiente, como elementos acessórios na constituição de rochas. Esses elementos, apesar de associados à toxidez, exigem tratamento diferenciado em relação aos xenobióticos, uma vez que diversos metais possuem essencialidade (Fe, Mn, Cu, Zn e Ni e benefício (Co comprovados para as plantas. Nesse contexto, o objetivo deste trabalho foi determinar os teores naturais dos metais Fe, Mn, Zn, Ni, Cu e Co nos solos de referência de Pernambuco. Foram coletadas amostras de solo nas três regiões fisiográficas (Zona da Mata, Agreste e Sertão, dos dois primeiros horizontes dos 35 solos de referência do Estado de Pernambuco. A digestão das amostras baseou-se no método 3051A (USEPA, 1998, e a determinação foi efetuada em ICP-OES. Correlações significativas foram estabelecidas entre os metais e entre estes e a fração argila do solo, em ambos os horizontes, indicando a associação comum da maioria dos metais com solos mais argilosos. A maioria dos solos apresentou teores de Fe, Mn, Zn, Cu, Ni e Co menores que os de solos de outras regiões do País, com litologia mais máfica, o que corrobora o fato de que os teores desses elementos são mais diretamente relacionados aos minerais Fe-magnesianos. Os resultados indicam baixo potencial dos solos de Pernambuco em liberar Cu, Co e Ni para plantas, enquanto deficiências de Zn, Fe e Mn são menos prováveis. Os teores naturais de Fe, Mn, Zn, Cu, Ni e Co determinados podem ser utilizados como base para definição dos Valores de Referência de Qualidade para os solos de Pernambuco, de acordo com o preconizado pela legislação nacional.Heavy metals are a group of elements with specific features and natural occurrence in the environment, representing an accessory in the formation of rocks. These elements, although associated with toxicity, must be treated different from xenobiotics, since many

  13. Catalisadores de Pt e PtSn suportados em biocarvões ativados para a eletro-oxidação do etanol

    OpenAIRE

    2016-01-01

    As células a combustível de etanol direto (DEFCs, Direct Ethanol Fuel Cells) são baseadas na eletro-oxidação do etanol à baixa temperatura e necessitam catalisadores à base de metais nobres, devido à cinética mais lenta para as reações de oxi-redução. Entre os catalisadores, a platina e as ligas de platina são os mais utilizados. Materiais para suportar os catalisadores são necessários a fim de reduzir a carga do mesmo empregada. Um dos suportes de catalisadores mais versáteis é o carvão ativ...

  14. Benzene hydrogenation catalysed by molybdenum carbide supported on Y zeolite; Hidrogenacao de benzeno catalisada por especies do tipo carbeto de molibdenio suportado em zeolita Y

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, Angela Sanches; Faro Junior, Arnaldo da Costa [Universidade Federal, Rio de Janeiro, RJ (Brazil). Inst. de Quimica. Dept. de Fisico-Quimica]. E-mail: asrocha@iq.ufrj.br; farojr@iq.ufrj.br; Silva, Victor Teixeira da [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil). Dept. de Engenharia Quimica]. E-mail: dasilva@aquarius.ime.eb.br

    2003-07-01

    Besides increasingly severe environmental legislation that limits the amount of aromatic hydrocarbons present in diesel fuels , improvement of the cetane number stimulates the development of hydrodesaromatization (HDA) catalysts. The present work investigates zeolite-supported molybdenum carbide catalysts , as an alternative for deep HDA. The transition metal carbides display catalytic activity similar to that of the noble metals catalysts used for this purpose, but they show larger thiotolerance, and have a lower price. Molybdenum carbide supported on Y zeolite with different silica/alumina ratios (SAR) and sodium contents were prepared starting from Mo(CO){sub 6} adsorbed on the zeolites and decomposed under different gaseous atmospheres, at high temperatures. The obtained materials were tested in benzene hydrogenation at 90 deg C, showing significant activity at atmospheric pressure, which characterizes the formation of carbides species. Strong dependence of the activity of the catalysts was also observed in relation to SAR and to the quantity of sodium of the zeolite supports. FTIR results show that the presence of protons in the zeolites dis favors the formation active molybdenum species. (author)

  15. Compounds Containing Tetragonal Cu2+ Complexes: Is the d<em>x>2–<em>y>2–d3<em>z>2–<em>r>2 Gap a Direct Reflection of the Distortion?

    DEFF Research Database (Denmark)

    García-Fernández, Pablo; Barriuso, María Teresa; García Lastra, Juan Maria

    2013-01-01

    It is widely assumed that the gap, Δ, between dx2–y2 and d3z2–r2 orbitals in fluorides and oxides containing tetragonal Cu2+ or Ag2+ complexes directly reflects the tetragonal distortion in the MX6 complex (M = d9 ion; X = F–, O2–). This assumption on that relevant quantity is shown to be not cor...

  16. Perfil comparativo de atletas de kickboxing e jiu-jitsu: estudo multidimensional da morfologia externa, desempenho em provas maximais de curta e média duração, força muscular e orientação para a realização de objetivos

    OpenAIRE

    Silva, Miguel Alexandre Guerreiro Leitão da

    2015-01-01

    Dissertação de mestrado em Treino Desportivo para Crianças e Jovens, apresentada à Faculdade de Ciências do Desporto e Educação Física da Universidade de Coimbra O Jiu-jitsu é um desporto de combate de alta intensidade, que combina ataques intermitentes de exercício predominantemente anaeróbio intercalado com períodos curtos de menor intensidade e suportados pela via aeróbia. O presente estudo objetivou traçar o perfil do atleta e compará-lo com os seus pares de outras disciplinas de comba...

  17. Efeito de metais Cobre (Cu e Zinco (Zn sobre a comunidade de macroinvertebrados bentônicos em riachos do sul do Brasil = The effect of metals (Cu and Zn on the benthic macroinvertebrate community in streams in southern Brazil

    Directory of Open Access Journals (Sweden)

    Silvia Vendruscolo Milesi

    2008-07-01

    Full Text Available O objetivo deste estudo foi avaliar os efeitos de metais (Cu e Zn sobre a comunidade de macroinverterados bentônicos. Foram amostrados, trimestralmente, entre setembro de 2006 e junho de 2007, organismos e água em oito trechos de riachos de duas bacias hidrográficas influenciadas por urbanização e agricultura. Foram estimados os valores de densidade de organismos, riqueza taxonômica e diversidade de Shannon. Para avaliação dos dados, foram utilizados testes de variância e regressão linear simples. Os resultados demonstraram variabilidade das concentrações dos metais e da macrofauna entre as estações do ano e riachos estudados. O metal Cobre (Cu apresentou influência apenas sobre a densidade Chironomidae e o metal Zinco (Zn apresentou efeito sobre a densidade total da macrofauna bentônica e de Chironomidae. Nenhum dos metais apresentou efeitos sobre ariqueza e diversidade de macroinvertebrados. Os resultados indicam potencial bioindicador da comunidade bentônica na avaliação da qualidade integrada do ambiente.The aim of this study was to evaluate the effect of metals (Cu and Zn on the benthic macroinvertebrate community. The organismsand water were collected quarterly between September 2006 and June 2007, in eight sites in streams of two hydrographic basins, influenced by urbanization and agriculture. The values of organism density, taxonomic richness and the Shannon diversity index were calculated. For data evaluation, tests of variance and simple linear regression were used. The results showed variability in the metal concentration and benthic community among seasons and studied streams. Cu showed influence only on Chironomidae density. Zn demonstrated effect on the benthic community and Chironomidae density. None of the metals presented effect on the macroinvertebrate richness and diversity. The results indicate a bioindicatorpotential of the benthic community in the evaluation of integral quality of the environment.

  18. Extratores para Cd, Cu, Cr, Mn, Ni, Pb e Zn em LATOSSOLOS tratados com biossólido e cultivados com milho Extractants for Cd, Cu, Cr, Mn, Ni, Pb and Zn in biossolid-amanded Oxisols cultivated with corn

    Directory of Open Access Journals (Sweden)

    Ana Rosa Martins dos Anjos

    2001-06-01

    Full Text Available O uso de biossólidos (lodo de esgoto em áreas agrícolas cria uma demanda por informações sobre o extrator mais adequado para se prever disponibilidade de metais pesados, presentes nesse resíduo, para as espécies vegetais cultivadas nessas áreas. A eficiência dos extratores HCl 0,1 mol L-1, Mehlich 3 e DTPA 0,005 mol L-1 pH 7,3 e da água régia na previsão da fitodisponibilidade de metais pesados presentes em solos tratados com biossólido foi avaliada através de um experimento com milho cultivado em LATOSSOLO VERMELHO Distrófico (LVd e LATOSSOLO AMARELO Distrófico (LAd. As parcelas experimentais foram vasos com capacidade para 0,5 m³de terra, distribuídos em blocos ao acaso, em esquema fatorial 4 x 4, quatro tratamentos (LVd+lodo, LVd, LAd+lodo e LAd e quatro métodos de extração com quatro repetições. O biossólido foi aplicado antes do cultivo do milho, numa quantidade total de 388 Mg ha-1, base seca, parcelada em 5 vezes espaçadas de 2 meses cada. Antes de semear o milho foi feita a amostragem da terra a 0-0,20 m, que foi analisada para teor total dos metais presentes com água régia e teores trocáveis removidos pelos extratores: solução 0,1 mol L-1 de HCl, Mehlich 3; DTPA-TEA pH 7,3. As plantas foram separadas em folha diagnose, folhas ao final do ciclo, pendão, colmo, bainha, sabugo, palha e grãos. Apesar da quantidade de biossólido aplicada aos solos, os teores totais dos metais analisados não excederam os limites críticos estabelecidos pela United States Environmental Protection Agency (USEPA e pela Diretriz da Comunidade Européia. As correlações feitas entre teor de metais presentes nas várias partes das plantas e teores dos metais removidos pelos diferentes extratores evidenciaram que Mehlich 3 foi eficiente apenas na previsão da fitodisponibilidade de Cu e Zn. Nenhum dos extratores testados foi eficiente na previsão da disponibilidade de Cd, Cr, Ni e Pb para as plantas de milho.The use of biossolids

  19. Produção comercializável e teores de Cu e Zn em cenoura em decorrência da ação residual de fósforo e composto de lixo em solo sob cerrado Marketable yield and contents of Cu and Zn in carrot as influenced by residual phosphate and urban compost in a cerrado soil

    Directory of Open Access Journals (Sweden)

    Manoel V. de Mesquita Filho

    2002-06-01

    Full Text Available Realizou-se em 1997, em condições de campo um experimento em Latossolo Vermelho Escuro distrófico argiloso sob cerrado de Brasília, para avaliar o efeito residual das aplicações em anos anteriores, a lanço de doses de fósforo (superfosfato triplo, e de composto de lixo na produção de cenoura (Daucus carota, cv. Brasília, assim como nos teores de cobre e zinco em raízes frescas. Aproveitou-se o mesmo delineamento experimental de blocos ao acaso com 3 repetições, no mesmo campo experimental dos experimentos anteriores distribuídos num esquema fatorial 3 x 5 incluindo-se 3 níveis de fósforo (0; 400 e 800 kg ha-1 de P2O5 e 5 níveis de composto de lixo (0; 20; 40; 60 e 80 t ha-1. A colheita foi realizada aos 90 dias após o plantio. A análise estatística dos dados de produção total de raízes revelou efeito residual da adubação dos últimos dois anos em linear e quadrático altamente significativo (pA field experiment was conducted on a clayey Yellow Red Oxisol to evaluate the residual effect of the application of phosphorus and urban waste compost of the previous two years on the root production of carrot cv. Brasília. The soil of the previous experiment design used a factorial consisting of three levels of phosphorus (0; 400 and 800 kg ha-1, applied as triple superphosphate combined with five levels of urban waste compost (0; 20; 40; 60 and 80 t.ha-1, was arranged in randomized complete blocks with three replicates. Carrot plants were harvested 90 days after planting. After the harvest, a linear and quadratic effect for phosphorus and urban waste compost (p<0,01 was observed. The linear interaction P x quadratic urban compost was highly significant (p<0,01. The maximum root total production was 26.5 t.ha-1 corresponding to 18.5 t ha-1 of marketable yield, estimated by the calculated doses of 762.5 kg ha-1 of P2O5 and 53.2 t ha-1 of urban waste compost according to the function: Y(PROD = 4.541143 + 4.0088 x 10-2 P2O5 + 2

  20. Microscopy modifications in an aged Cu-Al-Ni-Mn alloy; Modificacoes microestruturais em uma liga Cu-Al-Ni-Mn submetida ao envelhecimento

    Energy Technology Data Exchange (ETDEWEB)

    Gama, J.L.L. [Instituto Federal de Alagoas (IFAL), Maceio, AL (Brazil); Ferreira, R.A.S., E-mail: jorgelauriano@gmail.co [Universidade Federal de Pernambuco (DEM/UFPE), Recife, PE (Brazil). Dept. de Engenharia Mecanica

    2010-07-01

    An Cu-12Al-4Ni-3Mn shape memory alloy have been manufactured using an induction furnace of 24 KVA. After melting, chemical analyse was performed by X-ray fluorescence (XRF). The phase transformation of this alloy was studied in the different sequences produced during thermomechanic treatments. After homogenization, the ingot was solution treated at 850 deg C. At 750 deg C samples were submitted to a reduction by rolling to about 30% in thickness, followed by water quenching. In sequence, the ingot was cold-rolled at different thicknesses. In deformed state, sample of this alloy was submitted to the thermal analyse-DTA for identification of the phase transformation domains. For each identified domain, ageing was carried out, at different times, to evaluate the presence of the different phases. Samples were characterized ray-X diffraction. The results showed that the microstructural evolutions are of a complex nature. At 425 deg C temperature both recrystallization and precipitation of different phases were simultaneously observed. (author)

  1. Cu e Zn na cultura do sorgo cultivado em três classes de solos: I. Crescimento vegetativo e produção Cu and Zn in sorghum cultivated in three soil classes: I. Vegetative growth and yield

    Directory of Open Access Journals (Sweden)

    Hemmannuella C. Santos

    2009-04-01

    Full Text Available Os micronutrientes Cu e Zn são importantes para o bom desenvolvimento vegetativo e para a formação de grãos em cereais. Com o objetivo de avaliar o efeito da aplicação de Cu e Zn nos atributos de crescimento e na produção da cultura do sorgo realizou-se um experimento em ambiente protegido, no qual o delineamento foi em blocos casualizados, com a combinação de cinco doses de cobre (0, 0,26, 0,90, 1,54 e 1,80 mg kg-1 e cinco doses de zinco (0, 0,32, 1,1, 1,88 e 2,2 mg kg-1, combinadas na matriz Composto Central de Box, perfazendo 9 tratamentos, que foram aplicados em três classes de solo (Latossolo, Luvissolo e Neossolo, com 3 repetições. Avaliaram-se, aos 96 dias após a semeadura, os atributos de crescimento e a produção da cultura. A aplicação de cobre resultou em incrementos na área foliar, diâmetro do colmo, comprimento e diâmetro da panícula, matéria seca e na produção, o mesmo não ocorrendo para o zinco. As concentrações foliares de zinco indicaram interação negativa entre as doses aplicadas, enquanto entre os solos o Luvissolo foi o mais responsivo à aplicação dos nutrientes.The micronutrients copper and zinc are important for good vegetative growth and for grain formation in cereals. An experiment was carried out aiming to evaluate the effect of copper and zinc application upon growth attributes of sorghum and upon its grain yield. A randomized block experimental design was used, with a combination of five doses of copper (0, 0.26, 0.90, 1.54 and 1.80 mg kg-1 and five doses of zinc (0, 0.32, 1.1, 1.88 and 2.2 mg kg-1 combined by Box Central Composite design, resulting in nine treatments which were applied in three soil classes (Latosol, Alfisol and Entisol, with three replications. Ninety six days after sowing, growth attributes and sorghum yield were determined. The copper application increased leaf area, stem diameter, panicle length and diameter, dry matter yield and grain yield, however the same

  2. Adsorção de íons Cu2+ em latossolo vermelho-amarelo húmico

    Directory of Open Access Journals (Sweden)

    Jordão Cláudio Pereira

    2000-01-01

    Full Text Available In environmental studies it is necessary to know the adsorption behavior of metals by soils, since the unfavorable effects of heavy metals and even the micronutrients at high concentrations in the environment are related to these adsorbents' ability to immobilize them. A sample of a humic yellow red oxisol from Araponga region in the State of Minas Gerais, Brazil, was used to verify the adsorption behavior of Cu2+ ions in this substrate. The mathematical model described by Langmuir's adsorption equation in its linearized form was applied and the values of the maximum capacity b and those of the constant related to the bonding energy a were obtained. Aliquots of copper nitrate solutions containing several concentrations of this metal were added to soil samples, the pH being predetermined for developing the adsorption experiments. The chemical and physical characterization of soil sample were performed by determining the organic carbon, nitrogen and phosphorus concentrations, cation exchange capacity (CEC, pH, concentration of metals (Al, Fe, K, Mg, Ca, Zn, Cu, Ni, Cr, Co, Pb, and Cd, granulometric analysis and X-ray diffraction. Langmuir isotherms presented two distinct adsorption regions at both pH 4 and pH 5, showing that the adsorptive phenomenon occurs in two distinct stages. The adsorption sites for the lower part presented greater bonding energy and low adsorption capacity compared with the adsorption sites of the part of the curve corresponding to higher Cu concentrations in the equilibrating solution.

  3. Applying Freundlich, Langmuir and Temkin models in Cu and Pb soil sorption experiments Uso de los modelos de Freundlich, Langmuir y Temkin en experimentos de sorción de Cu y Pb en suelos Aplicação dos modelos de Freundlich, Langmuir e Temkin em ensaios de sorção de Cu e Pb no solo

    Directory of Open Access Journals (Sweden)

    F.A. Vega

    2011-11-01

    pH del suelo, experimentos de sorción y desorción de ambos elementos en muestras de todos los horizontes de tres suelos ácidos. Los objetivos fueron evaluar la capacidad de sorción y retención de Cu y Pb a través de los parámetros derivados de los ajustes a los modelos de Langmuir, Freundlich y Temkin; determinar la coherencia de las conclusiones deducidas de dichos parámetros, y estimar el papel de las características de todos los horizontes de esos suelos ácidos en la capacidad de fijación de Cu y Pb. Los resultados confirmaron la idoneidad del uso de los parámetros de las ecuaciones de Langmuir, Freundlich y Temkin para estudiar la sorción y retención de Cu y Pb por los suelos ácidos, ya que permitieron deducir que los mayores valores de la máxima capacidad de sorción o retención de ambos metales, deducidos de la ßL de Langmuir, se corresponden con los menores valores de la energía requerida para la fijación, indicados por la b’ de Temkin. Estos parámetros, junto con la KF derivada de los ajustes a la ecuación de Freundlich indicativa de la capacidad de sorción y retención, permitieron evaluar que las características de los suelos ácidos con mayor influencia en la fijación de Cu y Pb fueron el contenido de materia orgánica, seguido del contenido en óxidos de Al. Altos contenidos de ambos componentes, especialmente de materia orgánica, influyeron en un menor requerimiento de energía para la fijación de cationes metálicos ya que aumentaron la capacidad de sorción y retención de los suelos. El Al+3, catión mayoritario en el complejo de cambio de los horizontes estudiados, y el K+ fueron los responsables de la influencia de la CICe en la fijación de Cu y Pb en los horizontes de los suelos ácidos objeto de este trabajo.

    Em solos ácidos, as entradas de Cu e Pb de diferentes origens pressupõem um elevado risco de poluição ambiental. Por

  4. Power-law index and penetration depth of (Nd<em>xem>Smx>Gd1−2<em>x>)Ba2Cu3O7−δ films studied by AC susceptibility

    DEFF Research Database (Denmark)

    Li, Xiaofen; He, Dong; Grivel, Jean-Claude

    2012-01-01

    Superconducting (NdxSmxGd1−2x)Ba2Cu3O7−δ films with x=0, 0.1, 0.25, 0.33 were grown by PLD on STO single crystal substrates. The power-law index n and penetration depth λ are studied by AC susceptibility. During cooling, n in films with x ≠ 0 increases much slower compared with the films with x =....... The films with x ≠ 0 also tend to have a longer penetration depth. These properties might be related to the higher possibility for disorder in the mixed (Nd,Sm,Gd)BCO films....

  5. AVALIAÇÃO DA QUALIDADE DO AR NA ÁREA URBANA DE FREDERICO WESTPHALEN, RS, ATRAVÉS DA DETERMINAÇÃO DE Sr, Zr, Br, Cu E Zn EM AMOSTRAS DE LIQUENS

    Directory of Open Access Journals (Sweden)

    Mariele Fioreze

    2014-05-01

    Full Text Available A utilização de organismos vivos como indicadores da qualidade do ar atmosférico é uma alternativa que vem crescendo e ganhando destaque em diversos trabalhos pelo mundo. Dentre os organismos mais utilizados, estão os liquens, que se destacam pela alta capacidade de acumulação de elementos metálicos e do íon sulfato, gerando respostas significativas quando expostos a ambientes sob influência de agentes contaminantes. O objetivo deste trabalho foi avaliar a qualidade do ar atmosférico da cidade de Frederico Westphalen, RS, através da determinação de Sr, Zr, Br, Cu e Zn em amostras de liquens do gênero Parmotrema. Para tanto, foram comparadas as concentrações das espécies em estudo presentes em liquens que naturalmente se desenvolveram no perímetro urbano do município com as concentrações encontradas em amostras de liquens retiradas de área rural preservada da ação de poluentes urbanos. O uso do gênero Parmotrema como bioindicador da qualidade do ar atmosférico permitiu visualizar o aumento dos níveis de acumulação dos elementos em estudo em liquens da área urbana do município, o que comprova a existência de fontes de poluição que influenciam na qualidade do ar atmosférico nesse local.

  6. Preparo de óxido de nióbio suportado em alumina por deposição química em fase vapor: caracterização por espectroscopia vibracional e termogravimetria

    OpenAIRE

    Carmen Lúcia T. da Silva; José Luiz Zotin; Camorim,Vera Lúcia L.; Faro Jr.,Arnaldo C.; Maria Luiza Miranda Rocco

    1998-01-01

    Alumina supported niobium oxide was prepared by chemical vapor deposition (CVD) of NbCl5. The alumina was calcined and pretreated at differents temperatures in order to vary the density of OH groups on the surface which was determined by thermogravimetric analysis. A good correlation was found between the amount of anchored niobium and the total number of anionic sites (oxide and hydroxyl groups) on the surface of the alumina. The infrared spectra on the OH stretching region indicate that OH ...

  7. Preparo de óxido de nióbio suportado em alumina por deposição química em fase vapor: caracterização por espectroscopia vibracional e termogravimetria

    Directory of Open Access Journals (Sweden)

    Silva Carmen Lúcia T. da

    1998-01-01

    Full Text Available Alumina supported niobium oxide was prepared by chemical vapor deposition (CVD of NbCl5. The alumina was calcined and pretreated at differents temperatures in order to vary the density of OH groups on the surface which was determined by thermogravimetric analysis. A good correlation was found between the amount of anchored niobium and the total number of anionic sites (oxide and hydroxyl groups on the surface of the alumina. The infrared spectra on the OH stretching region indicate that OH groups coordinated to at least one tetrahedral aluminum were more reactive towards NbCl5.

  8. Preparation, characterization and evaluation of electrocatalysts supported on functionalized carbon black for polymer exchange membrane fuel cell applications; Preparacao, caracterizacao e avaliacao de eletrocatalisadores suportados em carbono funcionalizado para aplicacao em celulas a combustivel tipo PEM

    Energy Technology Data Exchange (ETDEWEB)

    Carmo, Marcelo do

    2008-12-18

    The fuel cell technology associated with the growing exigency of low environmental impact energy became prosperous in the world energy scenery. The fuel cell is basically a device that converts directly the chemical energy of a fuel into electrical and thermal energy with a continuous operation by the constant feed of a fuel. Especially, the carbon black Vulcan XC72 is usually employed as an electro catalyst support, and some factors as an accessible and high surface area in order to get maximum particles dispersion, pore size, adequate pore distribution and the presence of functional groups in the carbon black surface are considered fundamental characteristics for an innovative materials development. However, the Vulcan XC72 still reveals insufficient conditions for these purposes. This study consists in the preparation and in the physical chemical characterization of functionalized carbon black by hydrogen peroxide and by polymeric chains with proton conduction properties, and its posterior utilization as electro catalyst support for PEMFC and DMFC application. After the carbon functionalization, an improvement in the carbon black dispersion in water media was observed, a beneficial effect for electro catalyst preparation. It was also observed, that the functional groups and the polymeric chains worked as stabilizers in the particle growing, producing much more homogeneous electrocatalysts, exhibiting smaller average particle size. Especially, in the case of polymeric chains functionalization, a decrease in the ohmic drop was observed for this system, attributed to an improvement in the proton transference. (author)

  9. Resíduos industriais e agro-industriais : uma abordagem ecotecnológica na produção de fotocatalisadores suportados

    OpenAIRE

    William Leonardo da Silva

    2016-01-01

    A presente Tese, elaborada pela integração de artigos científicos publicados ou submetidos em periódicos internacionais, tem por objetivo geral investigar as potencialidades e limitações de resíduos industriais, acadêmicos e agroindustriais na obtenção de catalisadores para degradação de poluentes orgânicos. Foram utilizados resíduos industriais (banhos de galvanização, areias de fundição e petroquímico), acadêmicos (soluções residuais de aula de fotografia contendo prata e solução residual d...

  10. Uso de sílica e sílica-titânia organofuncionalizadas para a remoção de Cu(II em aguardentes The use of organofuncionalized silica and silica-titania for Cu (II removal in spirits

    Directory of Open Access Journals (Sweden)

    Leonardo B. Cantanhede

    2005-09-01

    Full Text Available Devido a necessidade da presença de cobre nos alambiques e as exigências cada vez mais acirradas com relação ao seu teor no destilado, é de interesse o desenvolvimento de metodologias para o controle deste metal nos destilados e/ou a sua remoção até níveis aceitáveis, em conformidade com as legislações nacional e internacional. Este trabalho investigou a potencialidade de dois sólidos: sílica modificada com trimetóxisili(propiletilenodiamina (Si-Dia, e sílica-titânia, também modificada com trimetóxisili(propiletilenodiamina (Si-Ti-Dia, como agentes removedores de íons Cu2+. Foram empregadas tanto soluções padrão de Cu2+, com teor alcoólico que simulavam aguardentes, como amostras reais de destilados. Os resultados indicam que um grama das matrizes Si-Dia e Si-Ti-Dia adsorvem 1,39 e 73,5mmol de Cu2+, respectivamente, a partir das soluções padrão, nas seguintes condições: tempo de contato 22h, pH 4,0; temperatura 25 ± 1,0°C e agitação constante. Para amostras reais, sob as mesmas condições de análises, o sólido Si-Dia reduziu as concentrações dos íons divalentes Cu, Zn e Fe em, respectivamente, 82, 83 e 64%, enquanto o Si-Ti-Dia, reduziu os mesmos íons em 88, 31 e 22%, respectivamente.The high levels of copper in Brazilian spirits is a problem of prominent importance, taking into account the relevance of this metal. This work investigates the efficiency of two solids: silica organofunctionalized with thimethoxysil(propil ethylenediamine (Si-Dia and silica-titania modified with the same organofunctionaling agent (Si-Ti-Dia as copper sequestrating agents in a Brazilian spirit obtained from sugar cane. It was verified that the matrices Si-Dia and Si-Ti-Dia are very good sequiestrating agents, reducing the concentrations of Cu, Zn and Fe in the studied spirit sample in 82, 83 and 64% and 88, 31 and 22%, respectively at 25 ± 1.0°C and pH 4.0.

  11. Efeitos da suplementação de fitase sobre a disponibilidade aparente de Mg, Ca, Zn, Cu, Mn e Fe em alimentos vegetais para a tilápia-do-nilo Effects of phytase supplementation on apparent availability of Mg, Ca, Zn, Cu, Mn, and Fe of plant feedstuffs for nile tilapia

    Directory of Open Access Journals (Sweden)

    Giovani Sampaio Gonçalves

    2005-12-01

    Full Text Available Cem juvenis de tilápia-do-nilo (Oreochromis niloticus; PV = 100.0 ± 5.0 g foram distribuídos em 10 tanques-rede com o objetivo de avaliar o efeito da suplementação da enzima fitase (0, 1.000 e 2.000 UFA/kg sobre a disponibilidade de minerais em alguns alimentos energéticos (milho, milho extrusado, farelo de trigo, farelo de arroz e farelo de sorgo e protéicos (farelo de soja extrusado, farelo de soja, farelo de girassol, farelo de algodão e glúten de milho utilizados na alimentação de tilápia-do-nilo (Oreochromis niloticus. Para determinação dos coeficientes de disponibilidade aparente (CDA do cálcio (Ca, magnésio (Mg, zinco (Zn, cobre (Cu, ferro (Fe e manganês (Mn, foram confeccionadas 31 rações, marcadas com 0,10% de óxido de crômio III uma referência (ração purificada e 30 contendo os dez alimentos e os diferentes níveis de suplementação da enzima fitase. O CDA dos nutrientes foi calculado com base no teor de crômio da ração e das fezes. A fitase aumenta, nos vegetais, a disponibilidade do Mg, Cu, Zn e Mn, os quais apresentam tendência diferenciada, em razão do seu valor biológico e do nível de suplementação de enzima.One hundred Nile tilapia juveniles (Oreochromis niloticus; BW= 100.0 ± 5.0 g were assigned to 10 experimental cages to evaluate the effects of phytase supplementation (0, 1,000, and 2,000 FTU/kg on calcium (Ca, magnesium (Mg, zinc (Zn, copper (Cu, iron (Fe and manganese (Mn availability of ten feedstuffs: five energetic (corn, extruded corn, wheat meal, rice meal and low-tannin sorghum and five protein (extruded soybean, soybean meal, sunflower meal, cottonseed meal and corn gluten meal. As reference, an albumin and gelatin-based diet [with 0.10 % chromic oxide (III as external marker] was fed to the juveniles. Thirty-one diets (one reference and 30 based on all feedstuffs and increasing levels of phytase were formulated to determine the coefficients of apparent availability of minerals (Mg

  12. Efeito de metais Cobre (Cu e Zinco (Zn sobre a comunidade de macroinvertebrados bentônicos em riachos do sul do Brasil - DOI: 10.4025/actascibiolsci.v30i3.677 The effect of metals (Cu and Zn on the benthic macroinvertebrate community in streams in southern Brazil - DOI: 10.4025/actascibiolsci.v30i3.677

    Directory of Open Access Journals (Sweden)

    Luiz Ubiratan Hepp

    2008-10-01

    Full Text Available O objetivo deste estudo foi avaliar os efeitos de metais (Cu e Zn sobre a comunidade de macroinverterados bentônicos. Foram amostrados, trimestralmente, entre setembro de 2006 e junho de 2007, organismos e água em oito trechos de riachos de duas bacias hidrográficas influenciadas por urbanização e agricultura. Foram estimados os valores de densidade de organismos, riqueza taxonômica e diversidade de Shannon. Para avaliação dos dados, foram utilizados testes de variância e regressão linear simples. Os resultados demonstraram variabilidade das concentrações dos metais e da macrofauna entre as estações do ano e riachos estudados. O metal Cobre (Cu apresentou influência apenas sobre a densidade Chironomidae e o metal Zinco (Zn apresentou efeito sobre a densidade total da macrofauna bentônica e de Chironomidae. Nenhum dos metais apresentou efeitos sobre a riqueza e diversidade de macroinvertebrados. Os resultados indicam potencial bioindicador da comunidade bentônica na avaliação da qualidade integrada do ambiente.The aim of this study was to evaluate the effect of metals (Cu and Zn on the benthic macroinvertebrate community. The organisms and water were collected quarterly between September 2006 and June 2007, in eight sites in streams of two hydrographic basins, influenced by urbanization and agriculture. The values of organism density, taxonomic richness and the Shannon diversity index were calculated. For data evaluation, tests of variance and simple linear regression were used. The results showed variability in the metal concentration and benthic community among seasons and studied streams. Cu showed influence only on Chironomidae density. Zn demonstrated effect on the benthic community and Chironomidae density. None of the metals presented effect on the macroinvertebrate richness and diversity. The results indicate a bioindicator potential of the benthic community in the evaluation of integral quality of the environment.

  13. New perspectives in the Fischer-Tropsch synthesis using cobalt supported on mesoporous molecular sieves; Novas perspectivas na sintese de Fischer-Tropsch usando cobalto suportado em peneiras moleculares mesoporosas

    Energy Technology Data Exchange (ETDEWEB)

    Souza, M.J.B.; Silva, A.O.S. [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Dept. de Engenharia Quimica; Fernandes Junior, V.J.; Araujo, A.S. [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Dept. de Quimica

    2004-07-01

    The conversion of synthesis gas to liquid products via Fischer-Tropsch synthesis (FTS) is an important process in the generation of clean fuels of sulfur and nitrogen compounds. Catalysts based on iron are very used in the conventional process due its cheap manufacture price. Recently the use of cobalt as promoter gave good results. MCM-41 mesoporous materials were discovered by Mobil scientists in the nineties and ever since they have great successes as support and catalyst in several processes of the oil industry as catalytic cracking, reformer and hydrotreating. In this work are presented new alternatives for FTS with the use of cobalt supported on molecular sieves of the type MCM-41. A comparative study with the usual catalysts based on silica was accomplished with different levels of cobalt. (author)

  14. Synthesis of carbon nanotubes by CVD method using iron and molybdenum-based catalysts supported on ceramic matrices;Sintese de nanotubos de carbono por CVD utilizando catalisadores a base de ferro e molibdenio suportados em matrizes ceramicas

    Energy Technology Data Exchange (ETDEWEB)

    Teixeira, Ana Paula de Carvalho

    2010-07-01

    Molybdenum is known for its synergistic effect in the synthesis of carbon nanotubes (CNs) by chemical vapor deposition (CVD method). When added to typical catalysts like iron, nickel, and cobalt, even in small quantities, it is increases the yield of these nanostructures. The presence of Mo also has an influence on the type and number of CN walls formed. Although this effect is widely documented in the literature, there is not yet a consensus about the mechanism of action of molybdenum in catalytic systems. The objective of the present work is to study the influence of molybdenum on the catalytic activity of iron nanoparticle-based catalysts supported on magnesium oxide (Fe/MgO system) in the synthesis of carbon nanotubes by the CVD method. The Mo concentration was systematically varied from null to molar ratio values four times greater than the quantity of Fe, and the obtained material (catalysts and carbon nanotubes) were broadly characterized by different techniques. In order to also study the influence of the preparation method on the final composition of the catalytic system phases, the catalytic systems (Fe/MgO e FeMo{sub x}/MgO) were synthesized by two different methods: co-precipitation and impregnation. The greatest CN yields were observed for the catalysts prepared by coprecipitation. The difference was attributed to better dispersion of the Fe and Mo phases in the catalyst ceramic matrix. In the precipitation stage, it was observed the formation of layered double hydroxides whose concentration increased with the Mo content up to the ratio of Mo/Fe equal to 0.2. This phase is related to a better distribution of Fe and Mo in this concentration range. Another important characteristic observed is that the ceramic matrix is not inert. It can react both with Fe and Mo and form the iron solid solution in the magnesium oxide and the phases magnesium-ferrite (MgFe{sub 2}0{sub 4}) and magnesium molybdate (MgMo0{sub 4}). The MgFe{sub 2}0{sub 4} phase is observed in all catalytic systems, while the MgMo0{sub 4} phase is observed in systems with Mo/Fe ratios greater than 0.2. In spite of the differences between the two methods of preparation, the influence of molybdenum is practically the same in the two series of catalysts studied. In both cases, the reaction yield was directly proportional to the molybdenum concentration. When the Mo concentration, however, was much higher than the Fe concentration, the CN synthesis yield decreased. The highest yields, therefore, were found when the Mo/Fe ratio was equal to 1. We propose that excess molybdenum leads to the formation of Mo metallic agglomerates that do not catalyze the CN synthesis by chemical vapor deposition. We also observed that the presence of molybdenum brought about the formation of multi-walled carbon structures (multi-walled nanotubes - MWNT - and bamboo-like structures), while iron promoted the preferential formation of nanotubes with one - SWNT - or few walls. Besides carbon and MgO nanostructures, iron carbide (Fe{sub 3}C) and molybdenum carbide (Mo{sub 2}C) (catalysts containing Mo) were also formed in all of the samples grown with CVD, and the quantity of Mo{sub 2}C increased with the increase in the Mo content in the catalyst. Based on the results obtained and the literature, two distinct regimes of action of Mo in the studied catalysts on the CVD carbon nanotubes synthesis from ethylene are proposed, when carried out in the conditions used in this work: 1) catalytic systems containing only Fe or small concentrations of Mo (MolFe =O, 0.02, 0.05, and 0.10). In this system, part of the Mo-containing species associate with the Fe phases present in the catalysts. During the decomposition of ethylene, Fe associates in particles with metallic Mo or Mo carbide. This association brings about the formation of MWNTs and carbon nanostructures with a higher degree of defects. The iron particles from the magnesium-ferrite phase or from the Fe solid solution in Mg bring about the formation of SWNTs and CNs with only a few walls. 2) Catalytic systems containing larger concentrations of Mo (Mo/Fe = 0.20, 0.50 and 1.00, and 4.00). In this system, two catalytic sites participate in the formation of CNs. In the first site, Fe nanoparticles from the magnesium-ferrite phase and the iron solid solution in Mg catalyze the synthesis of SWNTs or CNs with few walls. In the second site, Mo nanoparticles (from the magnesium molybdate phase), whether associated or not with Fe nanoparticles, catalyze the formation of MWNTs and other structures containing graphite multilayers. (author)

  15. Determination of isoelectric point and apparent surface coverage of alumina-supported molybdenum oxide by acoustophoresis; Determinacao de ponto isoeletrico e cobertura aparente de oxido de molibdenio suportado em alumina por acustoforese

    Energy Technology Data Exchange (ETDEWEB)

    Morgado Junior, Edisson [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES). Gerencia de Tecnologia de FCC]. E-mail: emorgado@petrobras.com.br; Fernandes, Marcio [PETROBRAS, Rio de Janeiro, RJ (Brazil). Unidade de Negocio de Exploracao e Producao. Gerencia de Operacao da Producao]. E-mail: mfernandes@petrobras.com.br; Fonseca, Dayse Lovatte; Zotin, Jose Luiz [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES). Gerencia de Hidrorrefino e Processos Especiais]. E-mails: dlovatte@petrobras.com.br; zotin@petrobras.com.br

    2007-04-15

    Catalysts based on molybdena supported on gamma-Al{sub 2}O{sub 3}, containing between 5 and 20 wt% MoO{sub 3}, were prepared and characterized by X-ray diffraction, nitrogen adsorption (BET method) and Acoustophoresis. This latter technique was applied to determine the Isoelectric Point (IEP) of the catalysts and their separate constituents: molybdenum and aluminum oxides. The results were compared to those previously obtained via Electrophoresis by Llambias at al. (1984). Accordingly, the IEP values of the supported catalysts were between the isoelectric points of Al{sub 2}O{sub 3} and MoO{sub 3}. However, the IEP value of MoO{sub 3} measured by acoustophoresis as 0.6, was significantly lower then the figures earlier reported by those researchers. This value is closer to those cited by the other references and to the predicted value estimated from IEP correlations. The apparent surface coverage calculated from acoustophoresis data was equivalent to the one from electrophoresis, in spite of the differences in the absolute IEP values of MoO{sub 3} and corresponding supported catalysts. It is proposed that, in this case, acoustophoresis is a more adequate technique for measuring IEP, minimizing or avoiding a probable effect of specific adsorption of cations on the surface of molybdenum oxide. (author)

  16. Produção de grãos e absorção de Cu, Fe, Mn e Zn pelo milho em solo adubado com lodo de esgoto, com e sem calcário Corn yield and uptake of Cu, Fe, Mn and Zn from sewage sludge-amended soil with and without liming

    Directory of Open Access Journals (Sweden)

    A. L. C. Martins

    2003-06-01

    Full Text Available O lodo de esgoto (LE, apesar do seu reconhecido valor como fertilizante, ainda é motivo de preocupação quando usado na agricultura, em virtude do potencial de absorção excessiva de metais pesados pelas plantas e entrada na cadeia alimentar. Para avaliar o efeito da adição de 0, 20, 40, 60 e 80 Mg ha-1 (com base no material seco de LE, aplicado de forma única ou parcelada em 2, 3 e 4 anos nas doses de 40, 60 e 80 Mg ha-1, respectivamente, com e sem calcário, na produção de grãos e massa seca da parte aérea e na absorção de Cu, Fe, Mn e Zn pelo milho, foi realizado, em Cordeirópolis (SP, um experimento em condições de campo, utilizando um Latossolo Vermelho distrófico típico, no período de 1983 a 1987. Foi utilizado o experimento em faixas ("split block" com quatro repetições. A maior dose de LE adicionou ao solo, em kg ha-1, 63, 3040, 25 e 152 de Cu, Fe, Mn e Zn, respectivamente. A produção de grãos e de massa seca da parte aérea aumentou linearmente com a adição de LE nos anos estudados. O LE aumentou significativamente as concentrações de Zn nas folhas e na parte aérea e provocou a redução nas concentrações de Fe e Mn, mas não alterou as de Cu. As concentrações dos metais nos grãos não foram influenciadas de forma significativa pela adição de LE, estando mesmo nas maiores doses, dentro dos níveis aceitáveis, sem causar restrição ao consumo humano. A absorção de Zn, Fe e Mn pelo milho foi significativamente reduzida pela adição de calcário. O Zn foi o metal que mais teve reduzida sua concentração na parte aérea pela adição de calcário. O parcelamento das doses de lodo de 40 a 80 Mg ha-1 provocou, de modo geral, aumento das quantidades absorvidas de metais pelo milho, sendo o Fe e o Zn os elementos que mais se acumularam na planta em resposta a esse parcelamento.Although the value of sewage sludge (SS as a fertilizer has long been recognized, it is still a matter of considerable concern

  17. Study and characterization of dosimeter LiF:Mg,Cu,P for using in aeronautical dosimetry; Estudo e caracterizacao do dosimetro de LiF:Mg,Cu,P para utilizacao em dosimetria aeronautica

    Energy Technology Data Exchange (ETDEWEB)

    Flavia, Hanna, E-mail: hannasantana.f@gmail.com [Universidade Paulista (UNIP), Sao Jose dos Campos, SP (Brazil); Federico, Claudio; Lelis, Odair; Pereira, Heloisa; Pereira, Marlon, E-mail: claudiofederico@ieav.cta.br [Instituto de Estudos Avancados (EFA-A/IEAV), Sao Jose dos Campos, SP (Brazil). Div. de Fisica Aplicada

    2014-07-01

    The effects of cosmic ionizing radiation incidents in aircraft components and crews has been a source of concern and motivated increasingly studies and improvements in the area. The low dose rates involved in this radiation field in aircraft flight altitudes imply Dosimetric necessity of using materials with high efficiency of detection, to enable studies lower cumulative doses resulting in shorter routes or lower altitude. The choice of thermoluminescent dosimeters LiF: Mg, Cu, P was done by having a detection efficiency of about fifteen times higher than its predecessor (LiF: Mg, Ti), and therefore, applied in very low doses dosimetry, and environmental dosimetry . The implementation of the use of pair dosimetric TLD-600H and 700H-TLD will serve as support for testing and studies on the effects of low doses of cosmic radiation in environmental dosimetry applied in the aviation environment in the usual flight altitudes. In this paper are presented the results of development of a methodology for dosimetry low doses of gamma radiation and neutrons using the pair dosimetric TLD-600H and 700H-TLD. The results demonstrate a sensitivity of dosimeters well above the dosimeters LiF: Mg, Ti confirming its suitability for dosimetry of low doses.

  18. Corrosion behavior of Cu Al Ni shape memory alloy in an oil land field produced fluid; Corrosao da liga com memoria de forma CuAlNi em fluido produzido de campo terrestre de petroleo

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Ricardo Estefany Aquino [PETROBRAS S.A., Aracaju/Maceio, SE/AL (Brazil). Unidade de Negocios SE-AL; Cruz, Maria Clara Pinto; Figueiredo, Renan T.; Souza, Luciete da Paixao; Araujo, Paulo M.M. [Universidade Tiradentes (UNIT), Aracaju, SE (Brazil)

    2008-07-01

    The corrosion behavior of the CuAlNi shape memory alloy in oil landfield produced groundwater was investigated with polarization curve and mass loss measurements, the latter carried out by immersion in laboratory and field tests. The physico-chemical analysis of five types of oil landfield produced groundwater showed the presence of H{sub 2}S and CO{sub 2}, high salinity, chloride, sulfide and iron ions and relatively neutral pH. The results from electrochemical tests in aerated produced groundwater, in the range of salinity encountered, suggested that the corrosion rate increases at higher saline concentrations. The results from field tests with corrosion test specimens showed a moderate to severe corrosion rate and suggested, in the other hand, that corrosion rates were influenced not only by salinity and oxidizing ions present in the flowing fluid, but also by solid materials in suspension, the fluid's temperature, and the flow velocity. This research is part of a major project which aims to develop couplings for landfield produced fluid transportation pipe connections without welded nor threaded joints. (author)

  19. Peletização do lodo de esgoto e adição de CaCO3 na produção de matéria seca e absorção de Zn, Cu e Ni pelo milho em três latossolos

    Directory of Open Access Journals (Sweden)

    R. S. Berton

    1997-12-01

    Full Text Available Em experimento de casa de vegetação, realizado em Campinas (SP, no período de janeiro a maio de 1980, estudaram-se os efeitos da peletização do lodo de esgoto, nas doses 0, 1 e 5% (v/v do material seco, na produção de matéria seca e na absorção de Zn, Cu e Ni pela parte aérea do milho (Zea mays L., em latossolo roxo (LR, latossolo vermelho-escuro (LE e latossolo vermelho-amarelo (LV, que receberam ou não adição de CaCO3 suficiente para elevação do pH em água para 6,0. O experimento foi realizado em vasos com dois litros de capacidade, delineados em blocos ao acaso, com três repetições, e os tratamentos arranjados num esquema fatorial. Após 200 dias de incubação dos solos com o lodo e CaCO3, cultivaram-se quatro plantas de milho em cada vaso. A parte aérea foi quantificada 56 dias após a germinação, sendo cortada, seca, pesada e analisada para os elementos Zn, Cu e Ni. Amostras de terra de cada tratamento foram retiradas e tiveram os metais extraídos pelo DTPA. A peletização do lodo de esgoto resultou em diminuição significativa na produção de matéria seca pela parte aérea do milho, nos três solos estudados, em comparação com o lodo não peletizado. A adição de CaCO3 proporcionou aumento significativo na produção de matéria seca do milho apenas nos dois solos mais ácidos (LE e LV e diminuiu o acúmulo de Zn na parte aérea desse vegetal cultivado no LE, sem distinção quanto ao tipo de lodo aplicado, não se observando diferenças significativas na absorção de Ni, em todos os solos analisados. A incorporação do lodo peletizado , que continha 19% menos Zn e Ni que o não peletizado, resultou em menor absorção de Zn, Cu e Ni nos três solos, exceto para o Ni no LR. Para todos os solos investigados, o método do DTPA mostrou-se mais adequado em prognosticar as quantidades disponíveis de Zn e de Cu para o milho, independentemente do tipo de lodo de esgoto aplicado e da elevação ou não do pH do

  20. Synthesis of 1,2,3-Triazole Derivatives and <em>in Vitroem> Antifungal Evaluation on <em>Candida> Strains

    Directory of Open Access Journals (Sweden)

    Almir G. Wanderley

    2012-05-01

    Full Text Available 1,2,3-Triazoles have been extensively studied as compounds possessing important biological activities. In this work, we describe the synthesis of ten 2-(1-aryl-1<em>H>-1,2,3-triazol-4-ylpropan-2-ols via copper catalyzed azide alkyne cycloaddition (CuAAc or <em>click chemistryem>. Next the<em> in vitroem> antifungal activity of these ten compounds was evaluated using the microdilution broth method against 42 isolates of four different <em>Candida> species. Among all tested compounds, the halogen substituted triazole 2-[1-(4-chlorophenyl-1<em>H>-(1,2,3triazol-4-yl]propan-2-ol, revealed the best antifungal profile, showing that further modifications could be done in the structure to obtain a better drug candidate in the future.

  1. Yttrium-enriched YBa2Cu3O<em>x> thin films for coated conductors fabricated by pulsed laser deposition

    DEFF Research Database (Denmark)

    Khoryushin, Alexey V.; Mozhaev, Peter B.; Mozhaeva, Julia E.;

    2013-01-01

    The effects of excess yttria on the structural and electrical properties of the YBa2Cu3Ox (YBCO) thin films are studied. The films were deposited on (LaAlO3)0.3–(Sr2AlTaO8)0.7 substrates by pulsed laser ablation from targets with different elemental composition. An increase of yttrium content...... of the target leads to formation of porous films with significantly improved current-carrying capabilities. Structural studies of these films reveal presence of yttria nanoparticles embedded into the YBCO matrix. The highest obtained critical current density in an external magnetic field of 5T was 2.6MA/cm2...... at 50K and 9.4MA/cm2 at 20K. The fabricated Y-enriched YBCO films remain c-oriented at least up to 600nm thickness with no significant suppression of the critical current density. © 2012 Elsevier B.V. All rights reserved....

  2. Estudo da capacidade de complexação de íons Cu2+ em solução aquosa usando celulose modificada com anidrido succínico e com poliaminas Study of copper removal from aqueous solutions using modified celluloses with succinic anhydride and polyamines

    Directory of Open Access Journals (Sweden)

    Gabriela S. Corti

    2004-12-01

    Full Text Available Nesse trabalho foi realizada a preparação de novos materiais, a partir da celulose, para complexar íons de metais pesados em solução aquosa e assim, descontaminar águas poluídas por tais metais. Na primeira parte foi realizada a modificação química da celulose usando o anidrido succínico. As funções carboxílicas introduzidas no material foram usadas para ancorar poliaminas produzindo-se três celuloses modificadas inéditas. Todos os materiais obtidos foram caracterizados por espectroscopia no infravermelho (IV e submetidos à análise elementar. A segunda parte do trabalho foi constituída da avaliação do poder de adsorção das celuloses modificadas obtidas em relação aos íons Cu2+ em solução aquosa. O estudo foi realizado usando a titulometria, um método analítico tradicional. Os vários materiais mostraram uma capacidade máxima de complexação variando entre 141 e 263 mg de Cu2+ por grama do material modificado. A eficiência na complexação dos íons Cu2+ mostrou-se proporcional ao número de funções aminas introduzidas na celulose.This work describes the preparation of new materials, derived from cellulose, to be used as complexing agents for heavy metal ions in aqueous solutions and, hence, to decontaminate waters polluted by such metals. The first part deals with the chemical modification of the cellulose using succinic anhydride. The carboxylic acid functions introduced in the material were used to anchor polyamines resulting in three novel modified celluloses. The materials obtained were characterized by elemental analysis and infrared spectroscopy (IR. The second part of the work features the evaluation of the adsorption capacity of the modified celluloses in relation to Cu2+ ions in aqueous solutions. The study was accomplished by titration, a traditional analytical method. The various materials showed a maximum complexing capacity ranging from 141 to 263 mg of Cu2+ per gram of the modified material. The

  3. Modelagem do Processo de Fragmentação de Catalisadores Suportados Durante a Pré-polimerização de Olefinas Modeling of Catalyst Fragmentation During Olefin Pre-polymerizations

    Directory of Open Access Journals (Sweden)

    Douglas M. Merquior

    2002-01-01

    Full Text Available Uma metodologia é proposta para descrever a morfologia das partículas de polímero que são obtidas durante os momentos iniciais da polimerização de olefinas via catálise heterogênea. O método é baseado na análise matemática da capacidade da partícula em liberar a energia mecânica acumulada no seu interior devido à rápida produção de polímero. O balanço entre as quantidades de energia acumulada e liberada é calculado com o auxílio de um modelo dinâmico da reação de pré-polimerização. A combinação da metodologia proposta com o modelo dinâmico permitiu a análise dos mecanismos de fragmentação, indicando a morfologia da partícula de polímero produzida em função do tamanho da partícula e da temperatura do reator.A model-based methodology is proposed for describing the morphology of the polymer particles that are obtained during the very early stages of the olefin polymerization. The method is based on the analysis of the particle capacity to release the amount of energy that is accumulated in its interior during the polymerization, due to the fast polymer production. The balance between the accumulated and released amounts of energy is calculated with the help of a dynamic pre-polymerization reaction model. The combination of the fragmentation criteria and of the polymerization model allows the analysis of the prepolymerization step, indicating the morphology of the final polymer particles as a function of the catalyst particle diameter and reactor temperature.

  4. Incorporação de CuSO4 residual em argamassa, como método de disposição final Incorporation of residual cuso4 into cement as a final disposal method

    Directory of Open Access Journals (Sweden)

    Matheus Paes Paschoalino

    2006-07-01

    Full Text Available Residual CuSO4 was incorporated into the mass utilized for cement preparation. To a cement mass with 1:0.5:5 of cement, lime and sand to 0.25, 0.50, 0.75 and 1.00% of residual CuSO4 were added. The sulfate was mixed separately with lime and water to induce metal precipitation. The hardened test bodies were submerged in Milli-Q water for three months. No Cu was detected in the water by Atomic Absorption Spectrometry. The best proportion for mechanical resistance and porosity is 0.50%. The cement is adequate for non-structural objects.

  5. Redox properties of an engineered purple Cu(A) azurin.

    Science.gov (United States)

    Sun, Dapeng; Wang, Xiaotang; Davidson, Victor L

    2002-08-01

    Purple Cu(A) centers are a class of binuclear, mixed-valence copper complexes found in cytochrome c oxidase and nitrous oxide reductase. An engineered Cu(A) protein was formed by replacing a portion of the amino acid sequence that contains three of the ligands to the native type I copper center of Pseudomonas aeruginosa azurin with the corresponding portion of sequence from the Cu(A) center of cytochrome c oxidase from Paracoccus denitrificans [Proc. Natl. Acad. Sci. USA 93 (1996) 461]. Oxidation-reduction midpoint potential (E(m)) values of the Cu(A) azurin of +399+/-10 and +380+/-2mV, respectively, were determined by cyclic voltammetry and spectrochemical titration. An n value of one was obtained, indicating that the redox reaction is cycling between the mixed valence and the fully reduced states. Whereas the E(m) value of native azurin is pH dependent, the E(m) value of Cu(A) azurin is not, as expected for the Cu(A) center. Similarities and differences in the redox properties are discussed in terms of the known crystal structures of Cu(A) centers in cytochrome c oxidase and Cu(A) azurin.

  6. Bond strength of W-Cu/CuCr integrated material

    Institute of Scientific and Technical Information of China (English)

    范志康; 梁淑华; 薛旭

    2001-01-01

    The bond strength of W-Cu/CuCr integrated material was investigated. The results show that the fracture of W-Cu/CuCr integrated material often takes place at W-Cu/CuCr interface. Some alloying elements enhance the bond of W and CuCr alloy, which results in the increase of the strength of the W-Cu/CuCr interface. And the fracture of the WCu/CuCr integrated material occurs in the CuCr alloy part, not at the W-Cu/CuCr interface. Chromium in CuCr alloy part of the integrated material can improve Cr diffusing from the CuCr alloy to W-Cu composite and can be alloyed (near the W-Cu/CuCr interface) in the W-Cu composite. Thus the strength of W-Cu/CuCr interface is also increased.

  7. Microstructure, impurity and metal cap effects on Cu electromigration

    Energy Technology Data Exchange (ETDEWEB)

    Hu, C.-K.; Gignac, L. G.; Ohm, J.; Breslin, C. M.; Huang, E.; Bonilla, G.; Liniger, E.; Rosenberg, R. [IBM T. J. Watson Research Center, Yorktown Heights, NY 10598 (United States); Choi, S.; Simon, A. H. [IBM Microelectronic Division, Hopewell Junction, NY 12533 (United States)

    2014-06-19

    Electromigration (EM) lifetimes and void growth of pure Cu, Cu(Mn) alloy, and pure Cu damascene lines with a CoWP cap were measured as a function of grain structure (bamboo, near bamboo, and polycrystalline) and sample temperature. The bamboo grains in a bamboo-polycrystalline grained line play the key role in reducing Cu mass flow. The variation in Cu grain size distribution among the wafers was achieved by varying the metal line height and wafer annealing process step after electroplating Cu and before or after chemical mechanical polishing. The Cu grain size was found to have a large impact on Cu EM lifetime and activation energy, especially for the lines capped with CoWP. The EM activation energy for pure Cu with a CoWP cap from near-bamboo, bamboo-polycrystalline, mostly polycrystalline to polycrystalline only line grain structures was reduced from 2.2 ± 0.2 eV, to 1.7 ± 0.1 eV, to 1.5 ± 0.1 eV, to 0.72 ± 0.05 eV, respectively. The effect of Mn in Cu grain boundary diffusion was found to be dependent on Mn concentration in Cu. The depletion of Cu at the cathode end of the Cu(Mn) line is preceded by an incubation period. Unlike pure Cu lines with void growth at the cathode end and hillocks at the anode end of the line, the hillocks grew at a starting position roughly equal to the Blech critical length from the cathode end of the Cu(Mn) polycrystalline line. The effectiveness of Mn on Cu grain boundary migration can also be qualitatively accounted for by a simple trapping model. The free migration of Cu atoms at grain boundaries is reduced by the presence of Mn due to Cu-solute binding. A large binding energy of 0.5 ± 0.1 eV was observed.

  8. Effect of the 1-hexene, the Al-Zr ratio and the temperature in ethylene copolymerization reactions with catalyst systems grafted on silica; Efeito do teor de hexeno-1, da relacao Al-Zr e da temperatura em reacoes de copolimerizacao de eteno, com sistemas cataliticos hibridos suportados em silica

    Energy Technology Data Exchange (ETDEWEB)

    Loureiro, Silvia R.R.; Silveira, Fernando; Galland, Griselda B.; Santos, Joao H.Z. dos [Rio Grande do Sul Univ., Porto Alegre, RS (Brazil). Inst. de Quimica]. E-mail:griselda@iq.ufrgs.br

    2003-07-01

    A series of copolymerization reactions with ethylene-1-hexene was performed with different amount of co-monomer, different aluminium-zirconium ratio and in two different temperature (40 deg C and 60 deg C). The reactions were accomplished by combining (nBuCp){sub 2} ZrCl{sub 2} and Cp{sub 2}ZrCl{sub 2} grafted on silica in different ratio (1:1, 3:1 and 1:3) and immobilization order. The catalyst activity in copolymerization reactions was shown to be dependent on the amount of the co-monomer, the Al-Zr ratio and the temperature. (author)

  9. Development of Nb{sub 2}O{sub 5}|Cu composite as AISI 1020 steel thermal spray coating for protection against corrosion by soil in buried structures; Desenvolvimento e uso do composito de Nb{sub 2}O{sub 5}|Cu como revestimento aplicado por aspersao termica sobre o aco AISI 1020 para protecao contra a corrosao pelo solo em estruturas enterradas

    Energy Technology Data Exchange (ETDEWEB)

    Regis Junior, Oscar [Universidade Tecnologica Federal do Parana, Ponta Grossa, PR (Brazil). Dept. de Mecanica; Silva, Jose Maurilio da; Portella, Kleber Franke [Instituto de Tecnologia para o Desenvolvimento, Curitiba, PR (Brazil). Dept. de Pesquisa em Engenharia Civil; Paredes, Ramon Sigifredo Cortes, E-mail: regis@utfpr.edu.br [Universidade Federal do Parana, Curitiba, PR (Brazil). Dept. de Mecanica

    2012-07-01

    An Nb{sub 2}O|Cu corrosion-resistant coating was developed and applied onto AISI 1020 steel substrate by Powder Flame Spray. A galvanostatic electrochemical technique was employed, with and without ohmic drop, in four different soils (two corrosively aggressive and two less aggressive). Behavior of coatings in different soils was compared using a cathodic hydrogen reduction reaction (equilibrium potential, overvoltage and exchange current density) focusing on the effect of ohmic drop. Results allow recommendation of Nb{sub 2}O{sub 5}|Cu composite for use in buried structure protection. (author)

  10. DESENVOLVIMENTO DE UM PROTOCOLO DE AVALIAÇÃO DO DESEMPENHO DE RECURSOS HUMANOS EM INSTITUIÇÕES DE ENSINO SUPERIOR/IES: NOTAS PARA A GESTÃO ACADÊMICA A PARTIR DO CASO DO CURSO DE TURISMO/UFJF – BRASIL

    Directory of Open Access Journals (Sweden)

    Thiago Duarte Pimentel

    2014-05-01

    Full Text Available Este artigo apresenta parte dos resultados de uma pesquisa realizada sobre a formação e inserção profissional no mercado de trabalho na área do turismo, no Brasil. Especificamente, discute-se aqui a realização de uma avaliação da gestão acadêmica do curso superior de bacharelado em turismo numa universidade federal brasileira à luz da gestão de seus recursos humanos. O estudo desenvolve uma metodologia própria, um protocolo de análise do perfil docente, baseado no cruzamento de técnicas de pesquisa quantitativas e qualitativas, suportado pela existência de um sistema nacional de base de dados e informações de docentes e pesquisadores que alimenta e torna possível a aplicação do protocolo. Os resultados encontrados evidenciam, em geral, a produtividade coletiva e o seu perfil relacionado ao caso em estudo e, em particular, os graus de especialização e assimetria na produtividade individual dos docentes, além de eventuais incongruências entre a especialização dos profissionais versus as áreas de atuação, disciplinas lecionadas e orientações realizadas. Como conclusão, duas contribuições centrais são advogadas: (1 a elaboração de um protocolo pesquisa próprio, e (2 os indicadores dele derivados que servem tanto para o levantamento de diagnóstico, para o monitoramento e avaliação do desempenho da gestão acadêmica.

  11. Use of analcime zeolite from mineral coal fly ash in adsorption of Cu{sup +2} and Cd{sup +2} in aqueous solutions; Utilizacao de zeolita analcima a partir de cinza leve de carvao mineral na adsorcao de Cu{sup +2} e Cd{sup +2} em soluoes aquosas

    Energy Technology Data Exchange (ETDEWEB)

    Rocha Junior, C.A.F.; Santos, S.C.A.; Angelica, R.S.; Neves, R.F.; Souza, C.A.G., E-mail: augustorocha2@gmail.com [Universidade Federal do Para (UFPA), Coqueiro, PA (Brazil)

    2011-07-01

    The use of zeolite for removing heavy metals from contaminated effluents over the years has been widespread due to its high cation exchange capacity in aqueous solutions. Thus this study aims to use analcime zeolite for removal of Cu{sup +2} and Cd{sup +2} from aqueous solutions at different concentrations, and the zeolitic material synthesized from coal fly ash generated in an alumina plant in northern Brazil . The use of zeolite analcime proved quite satisfactory, since this product has removed almost entirely Cu{sup +2} and Cd{sup +2} solutions with concentrations up to 200ppm, and demonstrated an average capacity for solutions of 400ppm, which shows good applicability of this material for the treatment of effluent contamination in the ranges studied. The adsorption models of Langmuir and Freundlich showed a good fit to experimental data generated in this work. (author)

  12. Estudo das interações entre o complexo polieletrolítico trimetilquitosana/carboximetilcelulose e Cu+2, ácido húmico e atrazina em solução aquosa Study of the interactions between the polyelectrolyte complex trimethylchitosan/carboxymethylcellulose and Cu+2, humic acid and atrazine in aqueous solution

    Directory of Open Access Journals (Sweden)

    Sergio P. Campana-Filho

    2009-01-01

    Full Text Available The polyelectrolyte complex (PEC resulting from the reaction of sodium carboxymethylcellulose (CMC and N,N,N-trimethylchitosan hydrochloride (TMQ was prepared and then characterized by infrared spectroscopy and energy dispersive X rays analysis. The interactions involving the PEC and Cu2+ ions, humic acid and atrazine in aqueous medium were studied. From the adsorption isotherms the maximum amount adsorbed (Xmax was determined as 61 mg Cu2+/g PEC, 171 mg humic acid/g PEC and 5 mg atrazine/g PEC. The results show that the CMC/TMQ complex has a high affinity for the studied species, indicating its potential application to remove them from aqueous media.

  13. Estudo da mobilidade de oxigênio intersticial em Bi2Sr2CaCu2O8+δ através de espectroscopia anelástica

    OpenAIRE

    Juliana Maria de Albuquerque Gimenez

    2004-01-01

    Desde a descoberta dos supercondutores com alta temperatura crítica, muitos estudos têm sido realizados em tomo de suas propriedades fisicas, tentando associá-Ias à supercondutividade. Átomos de oxigênio dissolvidos intersticialmente têm um papel importante na supercondutividade destes materiais, pois são capazes de mover-se com facilidade dentro da rede além de contribuírem na criação de buracos nos planos de CUO2. As medidas de atrito interno são ferramentas sensíveis ao estudo de defeitos ...

  14. Determinação de Mn, Cu e Zn em matrizes salinas após separação e pré-concentração usando Amberlite XAD-7 impregnada com Vermelho de Alizarina S

    Directory of Open Access Journals (Sweden)

    Santos Júnior Aníbal de Freitas

    2002-01-01

    Full Text Available The aim of this work was to explore the possibility of the application of a non-ionic resin obtained by impregnation of Alizarin Red S (VAS in Amberlite XAD-7 for manganese, copper and zinc separation and preconcentration in saline matrices. For these system, the metals were quantitatively retained, in the pH range 8.5-10.0, by using 0.50 g of solid phase, stirring time of five minutes and a total mass up to 200 mug of each cation. The sorbed elements were subsequently eluted and a fifty-fold, ten-fold and ten-fold preconcentration factor for to Zn, Cu and Mn were obtained, respectively.

  15. Organização e metodologia de ensino da natação no 1º ciclo do ensino básico em Portugal

    Directory of Open Access Journals (Sweden)

    Helena A. Rocha

    2014-06-01

    Full Text Available Foi objetivo deste estudo conhecer a organização e a metodologia de ensino da natação desenvolvida no âmbito da Expressão e Educação Físico-Motora no 1º ciclo do ensino básico (1º CEB em Portugal. A amostra incluiu 89 responsáveis por escolas de natação municipais e 100 professores que ministram as respetivas aulas. Para aferir a organização e a metodologia de ensino foram aplicados dois questionários, cujos resultados foram descritos com base em técnicas de análise estatística descritiva. Os resultados sugerem que a natação no 1º CEB rege-se sobretudo pelas orientações do Ministério da Educação. A restrição orçamental (60.0% e a dificuldade no transporte dos alunos da escola (54.0% para a piscina são as razões mais apontadas para a supressão da natação. O ensino é dirigido fundamentalmente para o terceiro e quarto ano (80.1%, com aulas de frequência semanal (64.4% em classes com um elevado número de alunos (13 a 16 alunos. Os principais objetivos das aulas estão relacionados com a adaptação ao meio aquático, privilegiando-se as habilidades aquáticas básicas (81.4%, num ensino pouco suportado em material pedagógico. Os dados relatados permitiram-nos identificar algumas insuficiências no enquadramento da natação no 1º CEB, provavelmente condicionantes da eficiência do processo de ensino-aprendizagem, ao nível da aquisição de habilidades aquáticas mais complexas.

  16. Estudo da labilidade de Cu(II, Cd(II, Mn(II e Ni(II em substâncias húmicas aquáticas utilizando-se membranas celulósicas organomodificadas Lability study of Cu(II, Cd(II, Mn(II and Ni(II complexed by aquatic humic substances using organomodified cellulose membranes

    Directory of Open Access Journals (Sweden)

    André Henrique Rosa

    2007-02-01

    Full Text Available In this work commercial filters papers were organomodified with tetraethylorthosilicate (TEOS and 3-aminopropyltriethoxysilane (3-APTS, aiming at the development of a new analytical procedure for in-situ speciation of labile and inert metal species in aquatic systems. Parameters that exert influence on the metal lability such as pH, chelating time, concentration and characteristics of the organic matter were studied in the laboratory using tests for metal recuperation. The results showed slower kinetics for Cu ion than for Ni, Mn and Cd in the absence of aquatic humic substances (AHS. The relative lability observed for complexed metals in aquatic humic substances using organomodified filter papers was Cu>>Cd>Ni>Mn. The pH values, structural characteristics and concentration of AHS exert strong influence on the lability of the metals. The results obtained showed that the utilization of organomodified filter papers can be an interesting and promising alternative for in situ characterization of metal lability in aquatic systems.

  17. Cu-67 Photonuclear Production

    Science.gov (United States)

    Starovoitova, Valeriia; Foote, Davy; Harris, Jason; Makarashvili, Vakhtang; Segebade, Christian R.; Sinha, Vaibhav; Wells, Douglas P.

    2011-06-01

    Cu-67 is considered as one of the most promising radioisotopes for cancer therapy with monoclonal antibodies. Current production schemes using high-flux reactors and cyclotrons do not meet potential market need. In this paper we discuss Cu-67 photonuclear production through the reaction Zn-68(γ,p)Cu-67. Computer simulations were done together with experiments to study and optimize Cu-67 yield in natural Zn target. The data confirms that the photonuclear method has potential to produce large quantities of the isotope with sufficient purity to be used in medical field.

  18. Ocitocina em cesarianas: qual a Melhor Maneira de Utilizá-la? Ocitocina en cesáreas: ¿cuál es la mejor manera de utilizarla? Oxytocin in cesarean sections: what is the best way to use it?

    Directory of Open Access Journals (Sweden)

    Eduardo Tsuyoshi Yamaguchi

    2007-06-01

    Full Text Available JUSTIFICATIVA E OBJETIVOS: A ocitocina é uterotônico utilizado em anestesia obstétrica, cuja administração, tanto profilática quanto terapêutica, justifica-se por reduzir a incidência de hemorragia após o parto. No entanto, ainda não está estabelecido o regime ideal de infusão em cesarianas eletivas. Este estudo tem o intuito de revisar as principais características fisiológicas e farmacológicas da ocitocina e discutir o seu uso racional pelos anestesiologistas, tendo em vista os seus efeitos colaterais. CONTEÚDO: A ocitocina é produzida pelo hipotálamo e armazenada pela hipófise posterior. No útero ela determina contração da musculatura lisa que é bastante importante para o controle de hemorragia após a dequitação. Ela atua, também, em outros sistemas, sendo relevante a diminuição da resistência vascular periférica com conseqüente hipotensão arterial. As ações extra-uterinas passam a ser importantes quando a ocitocina é feita em altas doses ou em bolus, especialmente em gestantes sob anestesia (seja bloqueio espinal ou anestesia geral apresentando hipovolemia, ou com alteração prévia no sistema cardiovascular. Diversos regimes de infusão têm sido estudados, variando-se a dose e/ou velocidade de infusão na tentativa de se estabelecer qual a maneira mais adequada de sua utilização. CONCLUSÕES: A ocitocina permanece como fármaco de primeira escolha para a prevenção e tratamento da atonia uterina após cesariana, especialmente por seu amplo espectro terapêutico. Apesar de estar disponível para a prática clínica há quase 50 anos, ainda não está estabelecido qual o regime adequado de sua infusão em cesarianas. A tendência atual é a utilização em infusão contínua de doses reduzidas, devendo ser evitada a administração em bolus.JUSTIFICATIVA Y OBJETIVOS: La ocitocina es un uterotónico utilizado en anestesia obstétrica, cuya administración, tanto profiláctica, como terapéutica, se

  19. Cu(I)/Cu(II) templated functional pseudorotaxanes and rotaxanes

    Indian Academy of Sciences (India)

    Subrata Saha; Pradyut Ghosh

    2012-11-01

    Threaded complexes like pseudorotaxanes, rotaxanes based on Cu(I)/Cu(II) ions have shown to be promising for the construction of mechanically interlocked molecular-level architectures. In this short review, we focus on the synthetic strategies developed to construct pseudorotaxanes and rotaxanes using Cu(I)/Cu(II) ions as template. Further, brief discussions on chemical and mechanical properties associated with some of the selected to Cu(I)/Cu(II) based pseudorotaxanes and rotaxanes are presented.

  20. Acilação de Friedel-Crafts do 2-metoxinaftaleno usando o ácido dodecafosfotúngstico suportado em sílica (HPW/SiO2 como catalisador e acetonitrila como solvente Friedel-Crafts acylation of the 2-methoxynaphthalene using the silica-supported dodecatungstophosphoric acid (HPW/SiO2 as catalyst and acetonitrile as solvent

    Directory of Open Access Journals (Sweden)

    Gil Luciano Guedes dos Santos

    2010-01-01

    Full Text Available The synthesis of fine chemicals intermediates using Friedel-Crafts acylation is one of the most important methods in chemical technology. In this work, the acylation of 2-methoxynaphthalene with acetic anhydride using a silica-supported dodecatungstophosphoric acid catalyst (HPW/SiO2 and acetonitrila as solvent was studied, showing that this reaction is a feasible alternative to produce intermediaries to replace the current methods of production. The reactions using acetonitrile solvent showed yields greater than or equal to the reactions using traditional solvents such as nitrobenzene and dichloroethane. Finally, the modified Eley-Rideal mechanism was proposed to elucidate the experimental data obtained.

  1. Estudo de catalisadores de níquel suportados em cinza de casca de arroz na reforma de metano com dióxido de carbono visando a produção de hidrogênio e gás de síntese

    Directory of Open Access Journals (Sweden)

    Karine Zanoteli

    2014-01-01

    Full Text Available Rice husk ash (RHA is used as a silica source for several purposes, among them to obtain metal catalysts, as was done in this work. The catalysts were characterized by chemisorption, physisorption, thermal analyses (TG, DSC, X-ray diffraction, X-ray fluorescence, temperature-programmed reduction and scanning electron microscopy. The catalysts synthesized with different Ni loadings supported on RHA were applied to the reaction of dry reforming of methane. The reaction was tested at three temperatures of catalytic reduction (500, 600 and 700 ºC. All synthesized catalysts were active for the studied reaction, with different H2/CO ratios achieved according to degree of metallic dispersion.

  2. Use of heterogeneous CaO and SnO{sub 2} catalysts supported on rice husk ash to produce biodiesel; Emprego de catalisadores heterogeneos de CaO e SnO{sub 2} suportados em cinza de casca de arroz na obtencao de biodiesel

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Ana Brigida [Instituto Federal do Espirito Santo, Vitoria, ES (Brazil); Silva, Paulo Roberto Nagipe da; Stumbo, Alexandre Moura, E-mail: nagipe@uenf.br [Laboratorio de Ciencias Quimicas, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Campos dos Goytacazes, RJ (Brazil); Freitas, Jair C.C. [Departamento de Fisica, Centro de Ciencias Exatas, Universidade Federal do Espirito Santo, Vitoria, ES (Brazil)

    2012-07-01

    Silica obtained from rice husk after acid leaching and calcination was compared to commercial silica as a catalyst support. CaO and SnO{sub 2} catalysts were prepared by impregnation and tested in the transesterification of soybean oil and the esterification of oleic acid. CaO catalysts showed basic character and were the most active for transesterification, whereas SnO{sub 2} catalysts were acid and the most effective for esterification. In both cases the performances of the catalysts prepared with rice husk ash and commercial silica were similar. These results demonstrate that rice husk is a cost-effective and environmentally-friendly source of silica that can be used as a catalyst support. (author)

  3. Evaluation of oxygenation time in SmBa{sub 2}Cu{sub 3}O{sub 7-{delta}} superconductors ceramics in air and ozone atmospheres; Avaliacao do tempo de oxigenacao nas ceramicas supercondutoras de SmBa{sub 2}Cu{sub 3}O{sub 7-{delta}} em atmosferas de ar e ozonio

    Energy Technology Data Exchange (ETDEWEB)

    Viana, P.R.P; Cunha, A.G., E-mail: pedrorupf@gmail.co [Instituto Federal do Espirito Santo (IFES), Vitoria, ES (Brazil)

    2010-07-01

    High temperature superconductors (HTSC) represent a major milestone in science. During the preparation of superconductors, oxygenation plays a key role, because oxygenation determines the distribution of charge carriers in these plans through the superconducting Cu-O and hence superconductivity. This paper proposes the preparation of polycrystalline superconductors using the ceramic method, and the step of oxygenation made with ozone gas (O{sub 3}). Ozone exerts chemical pressure on the compound, which has oxygen vacancies in its structure after the step of synthesis. The work was performed by varying the time between oxygenation 20, 40, 80 and 160 hours, with samples going through a process of oxygenation at 350 deg C after the step of synthesis. This study evaluates the time effect as oxygen can improve the superconducting properties such as resistivity and magnetic susceptibility. (author)

  4. Emprego da amostragem de suspensão na determinação de Cu e Zn em lapa antártica e Ni em sedimento de rio por espectrometria de absorção atômica com chama

    Directory of Open Access Journals (Sweden)

    Alves Flávia de Lima

    2001-01-01

    Full Text Available In order to demonstrate the feasibility of slurry sampling for environmental studies, different methodologies were developed for Cu and Zn in antarctic limpets and Ni in river sediment with FAAS detection. Studies focusing particle size, acid concentration, slurry stability, selectivity, among others were carried out in order to define the better conditions for slurry analysis. A study related to the depth profile for Ni in the Atibaia River sediment was made after optimization conditions for this element. For accuracy check, certified reference material was used as well as decomposition with microwave oven.

  5. 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.

  6. 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)

  7. Preparation and electromagnetic wave absorption of RGO/Cu nanocomposite

    Science.gov (United States)

    Zhang, Hui; Tian, Xingyou; Zhang, Xian; Li, Shikuo; Shen, Yuhua; Xie, Anjian

    2017-09-01

    We use a facile pyrolysis method to prepare reduced graphene oxide and copper nanocomposite (RGO/Cu) based on it. The product shows an outstanding wave absorption properties. The maximum reflection loss is up to-50.7 dB at 3.8 GHz. The reflection loss of-10 dB (90% power absorption) corresponds to a bandwidth of 11.2 GHz (3.4-14.6 GHz range) for the layer thickness of 2-5 mm. Therefore, it is suggested that the RGO/Cu nanocomposite is also a new kind of lightweight and high-performance EM wave absorbing material.

  8. Seletividade do pirofosfato de sódio e de cloretos não tamponados (CuCl2 e LaCl3 como extratores de alumínio associado à matéria orgânica em solos de restinga do estado de São Paulo Selectivity of sodium pyrophosphate and unbuffered chlorides (CuCl2 and LaCl3 as extractants of aluminum bound to soil organic matter in soils of the sandy coastal plain in São Paulo state

    Directory of Open Access Journals (Sweden)

    Maurício Rizzato Coelho

    2010-10-01

    Full Text Available O Al em complexos com matéria orgânica do solo é comumente determinado por técnicas de dissolução seletiva. Um extrator comum para essa forma do elemento é o pirofosfato de sódio. Devido à sua falta de seletividade para algumas amostras de solos, extratores não tamponados de Al, como CuCl2 e LaCl3, têm sido recomendados. A seletividade do pirofosfato de sódio (Al p e dos cloretos não tamponados de cobre (AlCu e de lantânio (AlLa como extratores de Al ligado à matéria orgânica foi avaliada em 31 perfis de solos (Espodossolos e Neossolos Quartzarênicos, representativos das áreas sob vegetação de restinga do litoral paulista. Os resultados foram comparados aos obtidos com oxalato de amônio e KCl, seguindo-se as interpretações comumente observadas na literatura quanto à capacidade extratora e seletividade dos reagentes utilizados. Pirofosfato careceu de total seletividade para amostras que apresentaram formas inorgânicas de Al. Os reagentes CuCl2 e LaCl3, por sua vez, foram mais seletivos para as formas de Al orgânico nas mesmas amostras, cuja ordem de extractabilidade foi: Al p>AlCu>AlLa . As diferentes habilidades extratoras e as relações entre os reagentes utilizados possibilitaram convergir evidências analíticas a fim de analisar e interpretar algumas determinações, como saturação por Al no húmus e estabilidade das interações Corg-metal. Horizontes espódicos Bs, Bhs e Bsm detiveram a maior estabilidade da interação Corg-metal e saturação por Al no húmus entre todos os horizontes estudados. Dos resultados encontrados, conclui-se que todos os reagentes analisados podem ser utilizados como extratores de Al associado à matéria orgânica dos solos, uma vez que permitiram estabelecer relações e interpretações contundentes quanto ao entendimento da química dos complexos Al-húmus dos solos de restinga estudados. Esses extratores, portanto, são adequados e têm potencial para os estudos e entendimento

  9. 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.

  10. Effects of advanced process approaches on electromigration degradation of Cu on-chip interconnects

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, M.A.

    2007-07-12

    This thesis provides a methodology for the investigation of electromigration (EM) in Cu-based interconnects. An experimental framework based on in-situ scanning electron microscopy (SEM) investigations was developed for that purpose. It is capable to visualize the EM-induced void formation and evolution in multi-level test structures in real time. Different types of interconnects were investigated. Furthermore, stressed and unstressed samples were studied applying advanced physical analysis techniques in order to obtain additional information about the microstructure of the interconnects as well as interfaces and grain boundaries. These data were correlated to the observed degradation phenomena. Correlations of the experimental results to recently established theoretical models were highlighted. Three types of Cu-based interconnects were studied. Pure Cu interconnects were compared to Al-alloyed (CuAl) and CoWP-coated interconnects. The latter two represent potential approaches that address EM-related reliability concerns. It was found that in such interconnects the dominant diffusion path is no longer the Cu/capping layer interface for interconnects as in pure Cu interconnects. Instead, void nucleation occurs at the bottom Cu/barrier interface with significant effects from grain boundaries. Moreover, the in-situ investigations revealed that the initial void nucleation does not occur at the cathode end of the lines but several micrometers away from it. The mean times-to-failure of CuAl and CoWP-coated interconnects were increased by at least one order of magnitude compared to Cu interconnects. The improvements were attributed to the presence of foreign metal atoms at the Cu/capping layer interface. Post-mortem EBSD investigations were used to reveal the microstructure of the tested samples. The data were correlated to the in-situ observations. (orig.)

  11. Study of hyperfine interactions in intermetallic compounds Gd(Ni,Pd,Cu)In, Tb(Ni,Pd)In, Dy(Ni,Pd)In and Ho(Ni,Pd)In; Estudo de interacoes hiperfinas em compostos intermetalicos Gd(Ni,Pd,Cu)In, Tb(Ni,Pd)In, Dy(Ni,Pd)In e Ho(Ni,Pd)In

    Energy Technology Data Exchange (ETDEWEB)

    Lapolli, Andre Luis

    2006-07-01

    Systematic behavior of magnetic hyperfine field (B{sub hf}) in the intermetallic compounds Gd(Ni,Pd,Cu)In Tb(Ni,Pd)In, Dy(Ni,Pd)In and Ho(Ni,Pd)In was studied by Perturbed Gamma-Gamma Angular Correlation spectroscopy. The measurements of B{sub hf} were carried out at the rare earth atom and in sites using the nuclear probes {sup 140}Ce and {sup 11}'1Cd respectively. The variation of hyperfine field with temperature, in most cases, follows the Brillouin function predicted from the molecular field theory. The hyperfine field values at rare earth atom sites obtained from {sup 140}Ce probe as well as at in sites obtained from {sup 111}Cd probe for each series of compounds were extrapolated to zero Kelvin B{sub hf}(T=0) from these curves. These values were compared with the values of the literature for other compounds containing the same rare earth element and all of them show a linear relationship with the ordering temperature. This indicates that the main contribution to B{sub hf} comes from the conduction electron polarization (CEP) through Fermi contact interaction and the principal mechanism of magnetic interaction in these compounds can be described by the RKKY type interaction. The values of B{sub hf}(T=0) for each family of intermetallic compounds RNiIn and RPdIn when plotted as a function of 4f spin projection of rare earth element also shows a linear relationship. Exceptions are the results for the compounds RNiIn obtained with {sup 111}Cd probe where a small deviation from linearity is observed. The results of the measurements carried out with the {sup 111}Cd probe were also analyzed to obtain the hyperfine parameters of the quadrupole interaction as a function of temperature for RPdln and GdNiIn compounds. The results show that for the compound GdPdIn there might be some Gd-In disorder at high temperature. (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. /Cu-Al System

    Science.gov (United States)

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

    2014-05-01

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

  14. Temperature-dependent activation energy of electromigration in Cu/porous low-k interconnects

    Science.gov (United States)

    Zheng, Hui; Yin, Binfeng; Zhou, Ke; Chen, Leigang; Kuo, Chinte

    2017-08-01

    In this paper, it was reported that the Time-to-Failure (TTF) of electromigration (EM) in Cu/porous low-k interconnects deviated from the classical Black's Equation at 250-350 °C due to moisture invasion. The EM activation energy (Ea) was 1.003 eV at above 300 °C, whereas the apparent value reduced to be negative below 300 °C, being accompanied by significantly narrowed TTF distribution. The corresponding change in the failure mode was distinctly revealed, which indicated that the oxidation of Ta-based liner due to moisture invasion through the porous low-k contributed significantly and modestly to the EM failure below and above 300 °C. The mechanism of the liner oxidation was interpreted with the theory of field-assisted cation migration, which suggested the steep slowdown of the oxidation from 275 to 300 °C could be ascribed to the substantial decrease in the moisture concentration at the low-k/Ta oxide interface, most probably owing to significant suppression of adsorption and surface diffusion of chemisorbed moisture in the nanoporous low-k. The inconsistent EM behaviors at the lower and higher temperatures were thus interpreted by the competition of intrinsic and extrinsic EM controlled separately by Cu diffusion along the Cu/SiN-based cap layer interface and the moisture-damaged Cu/Ta interface.

  15. Spin Correlations in the quasi-triangular magnet, Cu2(OH)3NO3

    Science.gov (United States)

    Gardner, Jason S.; Ehlers, Georg; Werner, Fletcher; Solin, S. A.

    2012-02-01

    We have investigated the structural and magnetic properties of the spin S = .5ex1 -.1em/ -.15em.25ex2 antiferromagnetic quasi-triangular lattice materials: Cu2(1-x)Zn2x(OH)3NO3 (0 Europhysics Letters, 93, 67001 (2011).[0pt] [2] J. Wu, A. K. Gangopadhyay, P. Kanjanaboos and S. A. Solin, J. Phys.: Condens. Matter 22, 334211 -- 334222 (2010).

  16. Planejamento estatístico de experimentos como uma ferramenta para otimização das condições de biossorção de Cu(II em batelada utilizando-se casca de nozes pecã como biossorvente Statistical design of experiments as a tool for optimizing the batch conditions of Cu(II biosorption using pecan nutshells as biosorbent

    Directory of Open Access Journals (Sweden)

    Jorge L. Brasil

    2007-06-01

    Full Text Available In order to reduce the total number of experiments for achieving the highest amount of adsorbed Cu2+ (qmax using pecan nutshells (Carya illinoensis as biosorbent, a full 2(4 factorial design with two central points was carried out (mass of biosorbent- m, pH, initial metallic ion concentration- C0, time of contact- t. In order to continue the optimization of the system, a central composite surface analysis design with two factors and five central points was carried out. The maximum amount of Cu2+ taken up by the pecan nutshells was 20 mg g-1. These results were confirmed by determining a Cu2+ isotherm using the best conditions attained by the statistical design of experiments.

  17. 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.

  18. PRR performance of Cu- and CuBr-vapor lasers

    Science.gov (United States)

    Fedorov, V. F.; Evtushenko, Gennadiy S.; Klimkin, Vladimir M.; Polunin, Yu. P.; Soldatov, Anatoly N.; Sukhanov, Viktor B.

    1998-06-01

    Results obtained from comparative analysis of the pulse repetition rate performance of Cu- and CuBr-vapor lasers operated at high pump pulse repetitions (approximately 100 kHz) are reported. For a CuBr laser with a 8 mm diameter discharge tube the laser pulse repetition rate as high as 270 kHz was realized.

  19. Cu Diffusion in Co/Cu/TiN Films for Cu Metallization

    Institute of Scientific and Technical Information of China (English)

    Xiuhua CHEN; Xinghui WU; Jinzhong XIANG; Zhenlai ZHOU; Heyun ZHAO; Liqiang CHEN

    2006-01-01

    Some information on how to use in-situ determined diffusion coefficient of Cu to make barrier layer of Cu metallization in ultra large scale integrations (ULSIs) was provided. Diffusion coefficients of Cu in Co at low temperature were determined to analyze Cu migration to Co surface layer. The diffusion depths were analyzed using X-ray photoelectron spectroscopy (XPS) depth profile to investigate the diffusion effect of Cu in Co at different temperatures. The possible pretreatment temperature and time of barrier layer can be predicted according to the diffusion coefficients of Cu in Co.

  20. 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.

  1. 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.

  2. 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>

  3. Synthesis, characterization and microwave absorption of carbon-coated Cu nanocapsules

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Yuping [Center for Engineering Practice and Innovation Education, Anhui University of Technology, Maanshan, (China); Feng, Chao; Liu, Xianguo; Jin, Chuangui, E-mail: liuxianguohugh@gmail.com [School of Materials Science and Engineering, Anhui University of Technology, Maanshan (China); Or, Siu Wing [Department of Electrical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, (Hong Kong)

    2014-03-15

    The microstructure and microwave absorption of carbon-coated Cu nanocapsules have been investigated. Carbon-coated Cu nanocapsules have been synthesized by an arc-discharge method. The paraffin-Cu/C nanocapsules composite shows excellent electromagnetic (EM) absorption properties. An optimal reflection loss (RL) value of –40.0 dB is reached at 10.52 GHz for a layer 1.9 mm thickness. RL exceeding –20 dB can be realized in any interval within the 1-18 GHz range by choosing an appropriate thickness of the absorbent layer between 1.1 and 10.0 mm. Theoretical simulation for the microwave absorption using the transmission line theory agrees reasonably well with the experimental results. The EM-wave absorption properties of nanocapsules materials are illustrated by means of an absorption-tube-map. The carbon-coated Cu nano capsule is an attractive candidate for EM-wave absorption, which significantly enriches the family of EM-wave nano absorbents. (author)

  4. 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.

  5. Structure-dependent size effects in CuTa/Cu nanolaminates

    Energy Technology Data Exchange (ETDEWEB)

    Gu, C. [State-Key Laboratory for Mechanical Behavior of Material, Xi’an Jiaotong University Xi’an, 710049 (China); Wang, F., E-mail: wangfei@mail.xjtu.edu.cn [State Key Laboratory for Strength and Vibration of Mechanical Structures, Xian Jiaotong University Xi’an, 710049 (China); Huang, P., E-mail: huangping@mail.xjtu.edu.cn [State-Key Laboratory for Mechanical Behavior of Material, Xi’an Jiaotong University Xi’an, 710049 (China); Xu, K.W. [State-Key Laboratory for Mechanical Behavior of Material, Xi’an Jiaotong University Xi’an, 710049 (China); Lu, T.J. [State Key Laboratory for Strength and Vibration of Mechanical Structures, Xian Jiaotong University Xi’an, 710049 (China)

    2016-03-21

    CuTa monolayers with different Ta contents (34 at% and 37 at%) and CuTa/Cu multilayers with varying nanoscale Cu layer thickness (3–24 nm) were prepared by magnetron sputtering. Their microstructure and mechanical properties were investigated by means of high resolution transmission electron microscopy (HRTEM) and nanoindentation testing. The microstructure of CuTa34 was pure amorphous phase while that of CuTa37 was amorphous phase embedded with nanoparticles. Adding Cu layers into the two different CuTa monolayers led to CuTa-Cu interfaces with different microstructures. For CuTa34/Cu, the interface was relatively straight and the Cu layers exhibited textured growth. For CuTa37/Cu, the interface was wavy and GBs (grain boundaries) were formed in the Cu layers. To investigate the influence of the two different microstructures on multilayer deformation, the residue indentation morphologies of CuTa/Cu were observed under scanning electronic microscope (SEM). For both CuTa34/Cu and CuTa37/Cu, SBs (shear bands) could be effectively inhibited if the Cu layers had a proper thickness. Dominant deformation mechanisms and size effects were proposed and discussed for CuTa/Cu thin films possessing different interfaces and Cu layer structures.

  6. A Novel Cyclodextrin Glycosyltransferase from Alkaliphilic <em>Amphibacillus> sp. NPST-10: Purification and Properties

    Directory of Open Access Journals (Sweden)

    Garabed Antranikian

    2012-08-01

    Full Text Available Screening for cyclodextrin glycosyltransferase (CGTase-producing alkaliphilic bacteria from samples collected from hyper saline soda lakes (Wadi Natrun Valley, Egypt, resulted in isolation of potent CGTase producing alkaliphilic bacterium, termed NPST-10. 16S rDNA sequence analysis identified the isolate as <em>Amphibacillus> em>sp. CGTase was purified to homogeneity up to 22.1 fold by starch adsorption and anion exchange chromatography with a yield of 44.7%. The purified enzyme was a monomeric protein with an estimated molecular weight of 92 kDa using SDS-PAGE. Catalytic activities of the enzyme were found to be 88.8 U mg−1 protein, 20.0 U mg−1 protein and 11.0 U mg−1 protein for cyclization, coupling and hydrolytic activities, respectively. The enzyme was stable over a wide pH range from pH 5.0 to 11.0, with a maximal activity at pH 8.0. CGTase exhibited activity over a wide temperature range from 45 °C to 70 °C, with maximal activity at 50 °C and was stable at 30 °C to 55 °C for at least 1 h. Thermal stability of the purified enzyme could be significantly improved in the presence of CaCl2. <em>K>m and <em>V>max values were estimated using soluble starch as a substrate to be 1.7 ± 0.15 mg/mL and 100 ± 2.0 μmol/min, respectively. CGTase was significantly inhibited in the presence of Co2+, Zn2+, Cu2+, Hg2+, Ba2+, Cd2+, and 2-mercaptoethanol. To the best of our knowledge, this is the first report of CGTase production by <em>Amphibacillus> sp. The achieved high conversion of insoluble raw corn starch into cyclodextrins (67.2% with production of mainly β-CD (86.4%, makes <em>Amphibacillus> sp. NPST-10 desirable for the cyclodextrin production industry.

  7. Dermatoses em renais cronicos em terapia dialitica

    Directory of Open Access Journals (Sweden)

    Luis Alberto Batista Peres

    2014-03-01

    Full Text Available Objetivo: As desordens cutâneas e das mucosas são comuns em pacientes em hemodiálise a longo prazo. A diálise prolonga a expectativa de vida, dando tempo para a manifestação destas anormalidades. Os objetivos deste estudo foram avaliar a prevalência de problemas dermatológicos em pacientes com doença renal crônica (DRC em hemodiálise. Métodos: Cento e quarenta e cinco pacientes com doença renal crônica em hemodiálise foram estudados. Todos os pacientes foram completamente analisados para as alterações cutâneas, de cabelos, mucosas e unhas por um único examinador e foram coletados dados de exames laboratoriais. Os dados foram armazenados em um banco de dados do Microsolft Excel e analisados por estatística descritiva. As variáveis contínuas foram comparadas pelo teste t de Student e as variáveis categóricas utilizando o teste do qui-quadrado ou o teste Exato de Fischer, conforme adequado. Resultados: O estudo incluiu 145 pacientes, com idade média de 53,6 ± 14,7 anos, predominantemente do sexo masculino (64,1% e caucasianos (90,0%. O tempo médio de diálise foi de 43,3 ± 42,3 meses. As principais doenças subjacentes foram: hipertensão arterial em 33,8%, diabetes mellitus em 29,6% e glomerulonefrite crônica em 13,1%. As principais manifestações dermatológicas observadas foram: xerose em 109 (75,2%, equimose em 87 (60,0%, prurido em 78 (53,8% e lentigo em 33 (22,8% pacientes. Conclusão: O nosso estudo mostrou a presença de mais do que uma dermatose por paciente. As alterações cutâneas são frequentes em pacientes em diálise. Mais estudos são necessários para melhor caracterização e manejo destas dermatoses.

  8. Electromigration of composite Sn-Ag-Cu solder bumps

    Science.gov (United States)

    Sharma, Ashutosh; Xu, Di Erick; Chow, Jasper; Mayer, Michael; Sohn, Heung-Rak; Jung, Jae Pil

    2015-11-01

    This study investigates the electromigration (EM) behavior of lead free Sn-Ag-Cu (SAC) solder alloys that were reinforced with different types of nanoparticles [Copper-coated carbon nanotubes (Cu/CNT), La2O3, Graphene, SiC, and ZrO2]. The composite solders were bumped on a Cu substrate at 220°C, and the resistance of the bumped solders was measured using a four wire setup. Current aging was carried out for 4 hours at a temperature of 160°C, and an increase in resistance was noted during this time. Of all the composite solders that were studied, La2O3 and SiC reinforced SAC solders exhibited the smallest resistances after current aging. However, the rate of change in the resistance at room temperature was lower for the SiC-reinforced SAC solder. The SAC and Graphene reinforced SAC solder bumps completely failed within 15 - 20 min of these tests. The SiC nanoparticles were reported to possibly entrap the SAC atoms better than other nanoparticles with a lower rate of EM. [Figure not available: see fulltext.

  9. Adubação foliar com micronutrientes em arroz irrigado, em área sistematizada

    Directory of Open Access Journals (Sweden)

    Marchezan Enio

    2001-01-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito da aplicação de micronutrientes em arroz irrigado, em área de várzea após a sistematização. Foi realizado durante três anos agrícolas em PLANOSSOLO Hidromórfico eutrófico arênico, instalado em local de onde foi retirada uma camada de solo de cerca de 30cm de profundidade. A adubação com N, P e K foi realizada de acordo com a recomendação técnica para a cultura. O delineamento experimental foi de blocos ao acaso com quatro repetições, constituído de um tratamento denominado "completo", contendo os micronutrientes boro (H3BO3, cobre (CuSO4, ferro (FeSO4, manganês (MnCl2, molibdênio (Na2MoO4 e zinco (ZnSO4 e de seis outros formados pela omissão de um micronutriente de cada vez, além de testemunha sem micronutrientes. Em 1996/97, foram aplicados 70g ha-1 Zn, 70g ha-1 Mn, 40g ha-1 Fe, 50g ha-1 B, 12,5g ha-1 Cu e 4g ha-1 Mo, via foliar, no perfilhamento e no início da formação do primórdio floral das plantas de arroz. Em 1997/98, foram utilizadas as mesmas soluções, porém com aplicação apenas no perfilhamento. Em 1998/99, as doses dos micronutrientes foram alteradas para 35g ha-1 Zn, 35g ha-1 Mn, 100g ha-1 B, 20g ha-1 Cu e 12g ha-1 Mo, aplicados no perfilhamento, não sendo utilizado o ferro no tratamento completo nem na composição dos demais tratamentos. A sistematização da área causou redução no teor de matéria orgânica, macro e micronutrientes, exceto o boro e aumento de alumínio no solo. Verificou-se que não houve efeito da aplicação foliar de micronutrientes no rendimento de grãos de arroz irrigado.

  10. Magnetic Moment of $^{59}$Cu

    CERN Multimedia

    2002-01-01

    Experiment IS358 uses the intense and pure beams of copper isotopes provided by the ISOLDE RILIS (resonance ionization laser ion source). The isotopes are implanted and oriented in the low temperature nuclear orientation set-up NICOLE. Magnetic moments are measured by $\\beta$-NMR. Copper (Z=29), with a single proton above the proton-magic nickel isotopes provides an ideal testground for precise shell model calculations of magnetic moments and their experimental verification. In the course of our experiments we already determined the magnetic moments of $^{67}$Ni, $^{67}$Cu, $^{68g}$Cu, $^{69}$Cu and $^{71}$Cu which provide important information on the magicity of the N=40 subshell closure. In 2001 we plan to conclude our systematic investigations by measuring the magnetic moment of the neutron-deficient isotope $^{59}$Cu. This will pave the way for a subsequent study of the magnetic moment of $^{57}$Cu with a complementary method.

  11. Determinação de biureto em uréia agroindustrial por espectrofotometria

    OpenAIRE

    Ferreira, R.B.; Franzini, V. P. [UNESP; Gomes Neto, José Anchieta [UNESP

    2007-01-01

    Foi desenvolvido um método espectrofotométrico para a determinação de biureto em fertilizantes à base de uréia empregando Cu(OH)2(s) como reagente analítico. O método se baseia na reação entre biureto e Cu(OH)2(s) e formação do complexo Cu(C2N3O2H5)2 de coloração violeta cujo espectro apresenta máximo de absorção em 510 nm. Após o estabelecimento das melhores condições analíticas, o método proposto foi aplicado na determinação de biureto em duas amostras comerciais de uréia, uma para pecuária...

  12. Bioassay-Guided Isolation and Identification of Cytotoxic Compounds from <em>Gymnosperma> <em>glutinosum> Leaves

    Directory of Open Access Journals (Sweden)

    Cristina Rodríguez-Padilla

    2012-09-01

    Full Text Available Bioassay-guided fractionation of hexane extracts of<em> Gymnosperma glutinosumem> (Asteraceae leaves, collected in North Mexico, afforded the known compounds hentriacontane (1 and (+-13<em>S>,14<em>R>,15-trihydroxy-<em>ent>-labd-7-ene (2, as well as the new <em>ent>-labdane diterpene (−-13<em>S>,14<em>R>,15-trihydroxy-7-oxo-<em>ent>-labd-8(9-ene (3. In addition, D-glycero-D-galactoheptitol (4 was isolated from the methanolic extract of this plant. Their structures were established on the basis of high-field 1D- and 2D NMR methods supported by HR-MS data. The cytotoxic activity was determined by using the <em>in vitroem> L5178Y-R lymphoma murine model. Hentriacontane (1 and the new <em>ent>-labdane 3 showed weak cytotoxicity, whereas the <em>ent>-labdane 2 showed significant (<em>p> < 0.05 and concentration dependent cytotoxicity (up to 78% against L5178Y-R cells at concentrations ranging from 7.8 to 250 µg/mL.

  13. em arquitetura e urbanismo

    Directory of Open Access Journals (Sweden)

    Ana Maria Sala Minucci Martins

    2006-01-01

    Full Text Available Está sendo desenvolvido projeto de pesquisa denominado Geometria Fractal e suas Aplicações em Arquitetura e Urbanismo, com o fito de estudar e desenvolver ferramentas analíticas e propositivas para serem aplicadas em arquitetura e urbanismo, com base em conceitos provenientes da geometria fractal.

  14. Antimicrobial Activity of Geranium Oil against Clinical Strains<em> em>of <em>Staphylococcus aureusem>

    Directory of Open Access Journals (Sweden)

    Monika Sienkiewicz

    2012-08-01

    Full Text Available The aim of this work was to investigate the antibacterial properties of geranium oil obtained from <em>Pelargonium graveolensem> Ait. (family <em>Geraniaceae>, against one standard <em>S. aureus em>strain ATCC 433000 and seventy clinical <em>S. aureusem> strains. The agar dilution method was used for assessment of bacterial growth inhibition at various concentrations of geranium oil. Susceptibility testing of the clinical strains to antibiotics was carried out using the disk-diffusion and E-test methods. The results of our experiment showed that the oil from <em>P. graveolensem> has strong activity against all of the clinical <em>S. aureusem> isolates—including multidrug resistant strains, MRSA strains and MLSB-positive strains—exhibiting MIC values of 0.25–2.50 μL/mL.

  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. Microsatellite Loci in the Gypsophyte <em>Lepidium subulatum em>(Brassicaceae, and Transferability to Other <em>Lepidieae>

    Directory of Open Access Journals (Sweden)

    José Gabriel Segarra-Moragues

    2012-09-01

    Full Text Available Polymorphic microsatellite markers were developed for the Ibero-North African, strict gypsophyte <em>Lepidium subulatumem> to unravel the effects of habitat fragmentation in levels of genetic diversity, genetic structure and gene flow among its populations. Using 454 pyrosequencing 12 microsatellite loci including di- and tri-nucleotide repeats were characterized in <em>L. subulatumem>. They amplified a total of 80 alleles (2–12 alleles per locus in a sample of 35 individuals of <em>L. subulatumem>, showing relatively high levels of genetic diversity, <em>H>O = 0.645, <em>H>E = 0.627. Cross-species transferability of all 12 loci was successful for the Iberian endemics <em>Lepidium cardaminesem>, <em>Lepidium stylatumem>, and the widespread, <em>Lepidium graminifoliumem> and one species each of two related genera, <em>Cardaria drabaem> and <em>Coronopus didymusem>. These microsatellite primers will be useful to investigate genetic diversity, population structure and to address conservation genetics in species of <em>Lepidium>.

  17. In situ study on reverse polarity effect in Cu/Sn–9Zn/Ni interconnect undergoing liquid–solid electromigration

    Energy Technology Data Exchange (ETDEWEB)

    Huang, M.L., E-mail: huang@dlut.edu.cn; Zhang, Z.J.; Zhao, N.; Yang, F.

    2015-01-15

    Highlights: • Abnormal reverse polarity effect in Cu/Sn–9Zn/Ni interconnect during L–S EM was observed. • The reverse polarity effect was resulted from directional diffusion of Zn to cathode. • Positive effective charge number is responsible for directional diffusion of Zn atom. • The effective charge number value of Zn was calculated to be +0.63 based on a model. • This effect is beneficial to EM reliability of micro-bump solder interconnect. - Abstract: Synchrotron radiation real-time imaging technology was used to in situ study the interfacial reactions in Cu/Sn–9Zn/Ni solder interconnects undergoing liquid–solid electromigration (L–S EM). The reverse polarity effect, evidenced by the continuous growth of intermetallic compound (IMC) layer at the cathode and the thinning of the IMC layer at the anode, was resulted from the abnormal directional migration of Zn atoms toward the cathode in electric field. This abnormal migration behavior was induced by the positive effective charge number (Z{sup ∗}) of Zn atoms, which was calculated to be +0.63 based on the Cu fluxes and the consumption kinetics of the anode Cu. Irrespective of the flowing direction of electrons, the consumption of Cu film was obvious while that of Ni film was limited. The dissolution of anode Cu followed a linear relationship with time while that of cathode Cu followed a parabolic relationship with time. It is more damaging with electrons flowing from the Ni to the Cu than that from the Cu to the Ni. The simulated Zn concentration distributions gave an explanation on the relationship between abnormal migration behavior of Zn atoms and the dissolution of Cu film under electron wind force. The abnormal directional migration of Zn atoms toward the cathode prevented the dissolution of cathode substrate, which is beneficial to improve the EM reliability of micro-bump solder interconnects.

  18. New Trifluoromethyl Triazolopyrimidines as Anti-<em>Plasmodium> <em>falciparum> Agents

    Directory of Open Access Journals (Sweden)

    Núbia Boechat

    2012-07-01

    Full Text Available According to the World Health Organization, half of the World’s population, approximately 3.3 billion people, is at risk for developing malaria. Nearly 700,000 deaths each year are associated with the disease. Control of the disease in humans still relies on chemotherapy. Drug resistance is a limiting factor, and the search for new drugs is important. We have designed and synthesized new 2-(trifluoromethyl[1,2,4]triazolo[1,5-<em>a>]pyrimidine derivatives based on bioisosteric replacement of functional groups on the anti-malarial compounds mefloquine and amodiaquine. This approach enabled us to investigate the impact of: (i ring bioisosteric replacement; (ii a CF3 group substituted at the 2-position of the [1,2,4]triazolo[1,5-<em>a>]pyrimidine scaffold and (iii a range of amines as substituents at the 7-position of the of heterocyclic ring; on <em>in vitroem> activity against <em>Plasmodium falciparumem>. According to docking simulations, the synthesized compounds are able to interact with <em>P. falciparumem> dihydroorotate dehydrogenase (<em>Pf>DHODH through strong hydrogen bonds. The presence of a trifluoromethyl group at the 2-position of the [1,2,4]triazolo[1,5-<em>a>]pyrimidine ring led to increased drug activity. Thirteen compounds were found to be active, with IC50 values ranging from 0.023 to 20 µM in the anti-HRP2 and hypoxanthine assays. The selectivity index (SI of the most active derivatives 5, 8, 11 and 16 was found to vary from 1,003 to 18,478.

  19. Beta decay of Cu-56

    NARCIS (Netherlands)

    Borcea, R; Aysto, J; Caurier, E; Dendooven, P; Doring, J; Gierlik, M; Gorska, M; Grawe, H; Hellstrom, M; Janas, Z; Jokinen, A; Karny, M; Kirchner, R; La Commara, M; Langanke, K; Martinez-Pinedo, G; Mayet, P; Nieminen, A; Nowacki, F; Penttila, H; Plochocki, A; Rejmund, M; Roeckl, E; Schlegel, C; Schmidt, K; Schwengner, R; Sawicka, M

    2001-01-01

    The proton-rich isotope Cu-56 was produced at the GSI On-Line Mass Separator by means of the Si-28(S-32, p3n) fusion-evaporation reaction. Its beta -decay properties were studied by detecting beta -delayed gamma rays and protons. A half-Life of 93 +/- 3 ms was determined for Cu-56. Compared to the p

  20. Composting of Rice straw with Effective Microorganisms (EM and its Influence on Compost Quality

    Directory of Open Access Journals (Sweden)

    Mohd Lokman Che Jusoh

    2013-02-01

    Full Text Available This study aims to assess the effect of EM application on the composting process of rice straw with goat manure and green waste and to evaluate the quality of both compost treatments. There are two treatment piles in this study, in which one pile was applied with EM and another pile without EM. Each treatment was replicated three times with 90 days of composting duration. The parameters for the temperature, pH, TOC and C/N ratio, show that decomposition of organic matter occurs during the 90-day period. The t-test conducted shows that there is a significant difference between compost with EM and compost without EM. The application of EM in compost increases the macro and micronutrient content. The following parameters support this conclusion: compost applied with EM has more N, P and K content (P < 0.05 compared to compost without EM. Although the Fe in compost with EM is much higher (P < 0.05 than in the compost without EM, for Zn and Cu, there is no significant difference between treatments. This study suggests that the application of EM is suitable to increase the mineralization in the composting process. The final resultant compost indicated that it was in the range of the matured level and can be used without any restriction.

  1. Electromigration-induced cracks in Cu/Sn3.5Ag/Cu solder reaction couple at room temperature

    Institute of Scientific and Technical Information of China (English)

    He Hongwen; Xu Guangchen; Guo Fu

    2009-01-01

    Electromigration (EM) behavior of Cu/Sn3.5Ag/Cu solder reaction couple was investigated with a high current density of 5× 103 A/cm2 at room temperature. One dimensional structure, copper wire/solder ball/copper wire SRC was designed and fabricated to dissipate the Joule heating induced by the current flow. In addition, thermomigration effect was excluded due to the symmetrical structure of the SRC. The experimental results in-dicated that micro-cracks initially appeared near the cathode interface between solder matrix and copper substrate after 474 h current stressing. With current stressing time increased, the cracks propagated and extended along the cathode interface. It should be noted that the continuous Cu6Sn5 intcrmetallic compounds (LMCs) layer both at the anode and at the cathode remained their sizes. Interestingly, tiny cracks appeared at the root of some long column-type Cu6Sn5 at the cathode interface due to the thermal stress.

  2. Electromigration-induced cracks in Cu/Sn3.5Ag/Cu solder reaction couple at room temperature

    Science.gov (United States)

    Hongwen, He; Guangchen, Xu; Fu, Guo

    2009-03-01

    Electromigration (EM) behavior of Cu/Sn3.5Ag/Cu solder reaction couple was investigated with a high current density of 5 × 103 A/cm2 at room temperature. One dimensional structure, copper wire/solder ball/copper wire SRC was designed and fabricated to dissipate the Joule heating induced by the current flow. In addition, thermomigration effect was excluded due to the symmetrical structure of the SRC. The experimental results indicated that micro-cracks initially appeared near the cathode interface between solder matrix and copper substrate after 474 h current stressing. With current stressing time increased, the cracks propagated and extended along the cathode interface. It should be noted that the continuous Cu6Sn5 intermetallic compounds (IMCs) layer both at the anode and at the cathode remained their sizes. Interestingly, tiny cracks appeared at the root of some long column-type Cu6Sn5 at the cathode interface due to the thermal stress.

  3. Screening and Analysis of the Potential Bioactive Components in Rabbit Plasma after Oral Administration of Hot-Water Extracts from Leaves of <em>B>ambusa em>>textilis em>McClure

    Directory of Open Access Journals (Sweden)

    Jia Sun

    2012-07-01

    Full Text Available <em>Bambusa textilisem> McClure is a traditional Chinese medicinal plant belonging to the Bambusoideae subfamily and used to treat chronic fever and infectious diseases. To investigate the bioactive compounds absorbed in the rabbit blood after oral administration of hot-<em>water extractem>>s from em>>the leaves of em>>B. textilisem> McClure, a validated chromatographic fingerprint method was established using LC-Q-TOF-MS. Twenty compounds in bamboo leaves and three potential bioactive compounds in rabbit plasma were detected. Of the twenty detected compounds <em>in vitroem>, fifteen of which were tentatively identified either by comparing the retention time and mass spectrometry data with that of reference compounds or by reviewing the literature. Three potential bioactive compounds, including (<em>E-p>-coumaric acid, (<em>Z-p>-coumaric acid, and apigenin-8-<em>C>-β-D-(2"-<em>O>-α-L-rhamnosyl-gluco-pyranoside, were detected in both <em>the leaves of em>>B. textilis em>McClure and rabbit plasma. Of the three compounds, apigenin-8-<em>C>-β-D-(2"-<em>O>-α-L-rhamnosylglucopyranoside was identified based on its UV, MS, and NMR spectra. This study provides helpful chemical information for further pharmacology and active mechanism research on <em>B. textilisem> McClure.

  4. Desenvolvimento e uso do compósito de Nb2O5|Cu como revestimento aplicado por aspersão térmica sobre o aço AISI 1020 para proteção contra a corrosão pelo solo em estruturas enterradas

    Directory of Open Access Journals (Sweden)

    Oscar Regis Junior

    2012-01-01

    Full Text Available An Nb2O|Cu corrosion-resistant coating was developed and applied onto AISI 1020 steel substrate by Powder Flame Spray. A galvanostatic electrochemical technique was employed, with and without ohmic drop, in four different soils (two corrosively aggressive and two less aggressive. Behavior of coatings in different soils was compared using a cathodic hydrogen reduction reaction (equilibrium potential, overvoltage and exchange current density focusing on the effect of ohmic drop. Results allow recommendation of Nb2O5|Cu composite for use in buried structure protection.

  5. Crescimento e sintomas visuais de deficências de micronutrientes em umbuzeiros Growth and visual symptoms of micronutrients deficiency in umbuzeiro

    Directory of Open Access Journals (Sweden)

    Orlando Sílvio Caires Neves

    2004-08-01

    Full Text Available O efeito da omissão de micronutrientes no crescimento e na manifestação de sintomas visuais de deficiência em mudas de umbuzeiro, cultivadas em solução nutritiva, foi avaliado nesse trabalho. O delineamento experimental utilizado foi o inteiramente casualizado, com quatro repetições e sete tratamentos, sendo estes: completo (todos os nutrientes, com omissão individual de B, Cu, Fe, Mn e Zn e omissão simultânea de Zn e Cu. A falta de B, Cu, Fe, Mn e Zn na solução nutritiva levou a um comprometimento no desenvolvimento das plantas, induzindo, inclusive, alterações morfológicas com sintomas característicos de deficiência nutricional de cada nutriente. O umbuzeiro mostrou-se mais exigente em B, Fe e Zn na fase inicial de crescimento do que em Mn e Cu. A redução na matéria seca total das mudas de umbuzeiro foi influenciada na seguinte ordem: Fe > B > Zn > Zn+Cu > Cu > Mn.The effect of micronutrient omission on growth and nutritional deficiency symptoms in umbuzeiro seedlings cultivated in nutrient solution was evaluated in this work. The experimental design was completely randomized with four replication and seven treatments, being them: complete (all the nutrients, with individual omission of B, Cu, Fe, Mn and Zn and simultaneous omission of Zn and Cu. The absence of B, Cu, Fe, Mn and Zn in the nutrient solution implicated on the reduction plants development inducing morphologic alterations with characteristic symptoms of nutritional deficiency of each nutrient. The umbuzeiro was shown more demanding in B, Fe and Zn in the initial phase of growth than Mn and Cu. The reduction in the total dry matter of the umbuzeiro seedlings was influenced in the following order: Fe > B > Zn > Zn+Cu > Cu > Mn.

  6. Genotoxicity of <em>Euphorbia hirtaem>: An <em>Allium cepaem> Assay

    Directory of Open Access Journals (Sweden)

    Kwan Yuet Ping

    2012-06-01

    Full Text Available The potential genotoxic effects of methanolic extracts of <em>Euphorbia hirta em>which is commonly used in traditional medicine to treat a variety of diseased conditions including asthma, coughs, diarrhea and dysentery was investigated using <em>Allium cepaem> assay. The extracts of 125, 250, 500 and 1,000 µg/mL were tested on root meristems of <em>A. cepaem>. Ethylmethanesulfonate was used as positive control and distilled water was used as negative control. The result showed that mitotic index decreased as the concentrations of <em>E. hirtaem> extract increased. A dose-dependent increase of chromosome aberrations was also observed. Abnormalities scored were stickiness, c-mitosis, bridges and vagrant chromosomes. Micronucleated cells were also observed at interphase. Result of this study confirmed that the methanol extracts of <em>E. hirta em>exerted significant genotoxic and mitodepressive effects at 1,000 µg/mL.

  7. Synthesis, Structure, and Photophysical Properties of Two Four-Coordinate Cu(I)-NHC Complexes with Efficient Delayed Fluorescence.

    Science.gov (United States)

    Wang, Zhiqiang; Zheng, Caijun; Wang, Weizhou; Xu, Chen; Ji, Baoming; Zhang, Xiaohong

    2016-03-07

    Two luminescent cationic heteroleptic four-coordinate Cu(I) complexes supported by N-heterocyclic carbene ligand and diphosphine ligand were successfully prepared and characterized. These complexes adopt typical distorted tetrahedral configuration and have high stability in solid state. Quantum chemical calculations show carbene units have contributions to both highest occupied molecular orbitals and lowest unoccupied molecular orbitals of these Cu(I)-NHC complexes, the lowest-lying singlet and triplet excitations (S0 → S1 and S0 → T1) of [Cu(Pyim)(POP)](PF6) are dominated by metal-to-ligand charge transfer (MLCT) transition, while the S0 → S1 and S0 → T1 excitations of [Cu(Qbim)(POP)](PF6) are mainly MLCT and ligand-centered transitions, respectively. These Cu(I)-NHC complexes show efficient long-lifetime emissions (λem = 520 nm, τ = 79.8 μs, Φ = 0.56 for [Cu(Pyim)(POP)](PF6), λem = 570 nm, τ = 31.97 μs (78.99%) and 252.2 μs (21.01%), Φ = 0.35 for [Cu(Qbim)(POP)](PF6)) in solid state at room temperature, which are confirmed as delayed fluorescence by investigating the emissions at 77 K.

  8. GMI in FeCuNbSiB/Cu multilayers

    Energy Technology Data Exchange (ETDEWEB)

    Correa, M.A. [Departamento de Fisica, CCNE, UFSM, 97105-900, Santa Maria, RS (Brazil)]. E-mail: mmacorrea@gmail.com; Viegas, A.D.C. [Departamento de Fisica, CCNE, UFSM, 97105-900, Santa Maria, RS (Brazil); Silva, R.B. da [Departamento de Fisica, CCNE, UFSM, 97105-900, Santa Maria, RS (Brazil); Andrade, A.M.H. de [Departamento de Fisica, CCNE, UFSM, 97105-900, Santa Maria, RS (Brazil); Sommer, R.L. [Centro Brasileiro de Pesquisas Fisicas, 22290-180, Rio de Janeiro, RJ (Brazil)

    2006-10-01

    Very high magnetoimpedance (MI) measured at frequencies up to 1.8 GHz in single and multilayered thin films with composition Fe{sub 73.5}Cu{sub 1}Nb{sub 3}Si{sub 13.5}B{sub 9} and (Fe{sub 73.5}Cu{sub 1}Nb{sub 3}Si{sub 13.5}B{sub 9}+Cu) are reported. The magnetic properties of both systems are also compared. MI ratio as high as 300% for the multilayered samples were obtained.

  9. Hydrazone based luminescent receptors for fluorescent sensing of Cu{sup 2+}: Structure and spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Mukherjee, Soma, E-mail: sommukh445@yahoo.co.in [Department of Environmental Science, University of Kalyani, Kalyani, Nadia, 741235 West Bengal (India); Mal, Palash [Department of Environmental Science, University of Kalyani, Kalyani, Nadia, 741235 West Bengal (India); Stoeckli-Evans, Helen [Institute of Physics, University of Neuchâtel, rue Emile-Argand 11, CH-2000 Neuchâtel (Switzerland)

    2014-11-15

    Two new luminescent hydrazones, HL1 and HL2 were investigated for selective and sensitive fluorescent recognition of Cu{sup 2+} in aqueous medium (CH{sub 3}CN/H{sub 2}O (1:4, v/v) solvent system) with a 1:1 binding stoichiometry. The emission peak of HL (λ{sub em}=405 nm), undergoes significant quenching upon complexation with Cu{sup 2+}. The quantum yields for the receptors and in situ formed Cu{sup 2+} complexes were determined. The absorption ratiometric analysis was carried out in presence of various metal ions to confirm the selectivity of the receptors towards Cu{sup 2+}. They were able to detect Cu{sup 2+} with a ∼0.9 µM detection limit as indicated by fluorimetric measurements. The molecular structures of the receptors were determined by single crystal X-ray diffraction analysis. - Highlights: • Small molecule luminescent hydrazones were developed for recognition of Cu{sup 2+}. • Selectivity and sensitivity were studied spectroscopically in aqueous medium. • Binding stoichiometry, association constant, and quantum yields were calculated. • Receptors have low detection limit for Cu{sup 2+}. • Crystal structures of the receptors were solved by X-ray diffractometry.

  10. <em>In Vitroem> Antioxidant Properties of Flavonoids and Polysaccharides Extract from Tobacco (<em>Nicotiana> em>tabacum> L. Leaves

    Directory of Open Access Journals (Sweden)

    Jing-Lu Wang

    2012-09-01

    Full Text Available In the present study, antioxidant properties of flavonoids and polysaccharides from tobacco (<em>Nicotiana> tabacumem> L. leaves were evaluated in several <em>in vitroem> systems, e.g., scavenging activities on hydroxyl, superoxide anion, 1,1-diphenyl-2-picrylhydrazyl (DPPH and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid (ABTS radicals, and reducing power. Flavonoids showed much better activity than polysaccharides in scavenging activities on free radicals. When compared to the positive control, ascorbic acid, both showed weaker antioxidant potential. However, flavonoids possessed comparable superoxide anion, DPPH and ABTS radical scavenging abilities to ascorbic acid at high concentration (600 μg/mL. Meanwhile, it was found that flavonoids had prominent effects on the reducing power, which was equivalent to ascorbic acid, and was significantly higher than polysaccharides. These results clearly indicate that flavonoids are effective in scavenging free radicals and have the potential to be powerful antioxidants. Thus, tobacco leaves could be considered as a potential source of natural antioxidants for food, pharmaceutical, cosmetics or nutraceutical industries.

  11. Cu-Cr Literature Review

    Energy Technology Data Exchange (ETDEWEB)

    Need, Ryan F. [Los Alamos National Laboratory

    2012-08-09

    Cu-Cr alloys are part of a class of face-centered cubic (FCC)-body-centered cubic (BCC) composites that includes similar alloys, such as Cu-Nb and Cu-Ta. When heavily deformed, these FCC-BCC materials create 'in situ' composites with a characteristic structure-nanoscale BCC filaments in a ductile FCC matrix. The strength of these composites is vastly greater than predicted by the rule of mixtures, and has been shown to be inversely proportional to the filament spacing. Lower raw materials costs suggest that Cu-Cr alloys may offer more economical solution to high-strength, high-conductivity wire than either their Nb or Ta counterparts. However, Cr is also more brittle and soluble in Cu than Nb or Ta. These qualities necessitate thermal treatments to remove solute atoms from the Cu matrix, improve conductivity, and maintain the ductility of the Cr filaments. Through the use of different thermomechanical processing routes or the addition of select dopants, alloys with strength in excess of 1 GPa at 70% IACS have been achieved. To date, previous research on Cu-Cr alloys has focused on a relatively small number of alloy compositions and processing methods while the effects of dopants and ageing treatments have only been studied independently. Consequently, there remains considerable opportunity for the development and optimization of these alloys as a leading high-strength, high-conductivity material.

  12. E-books didáticos nos ambientes de aprendizagem em rede

    Directory of Open Access Journals (Sweden)

    Charles Rodrigues

    2015-06-01

    Full Text Available Apresenta um estudo sobre a relação entre os e-books e o ambiente virtual de aprendizagem (AVA suportado por dispositivos eletrônicos conectados à Internet. O objetivo é evidenciar as possibilidades e as vantagens do uso de e-books. Trata-se do resultado decorrente de uma pesquisa exploratória e estudos bibliográficos, caracterizando no conjunto uma pesquisa descritiva de base qualitativa. Os e-books educativos podem ser paradidáticos, quando são usados na aprendizagem sem terem sido originalmente escritos para apoiar as aulas. O uso de e-book vinculado ao ambiente de aprendizagem suportado por dispositivo eletrônico e conectado à Internet revoluciona a ideia de espaço de atividades pedagógicas, incorporando ao processo recursos digitais como calculadora, mapas e localizadores guiados por satélite, além de todo o acervo de informações disponível na Internet. Entre outras soluções de comunicação e gestão, os espaços interativos de postagem das atividades permitem ainda o gerenciamento eficaz do percurso de aprendizagem dos estudantes.

  13. Cu-ZSM-5, Cu-ZSM-11, and Cu-ZSM-12 Catalysts for Direct NO Decomposition

    DEFF Research Database (Denmark)

    Kustova, Marina; Kustov, Arkadii; Christiansen, Sofie E.

    2006-01-01

    Cu-ZSM-5 has for many years been recognized as a unique catalyst for direct NO decomposition. Here, it is discovered that both Cu-ZSM-11 and Cu-ZSM-12 are about twice as active as Cu-ZSM-5. This difference is attributed to the active sites located almost exclusively in the straight zeolite pores...

  14. Possible mechanism of superconductivity in CuO-Cu interface

    CERN Document Server

    Amelin, I I

    2002-01-01

    The CuO two-dimensional lattice consisting of the Cu sup 2 sup + and O sup 1 sup - ions which form the narrow partially filled two-dimensional zone is apparently formed in the CuO-Cu interface on the copper oxide surface. In this case formation of local electron pairs (LEP) is possible in the plane oxygen subsystem due to the Shubin-Vonsovskii conditions. In this approximation rough evaluation of the LEP formation temperature results in the T* approx 10 sup 4 K value. The temperature of the initial Bose-Einstein condensation by the concentration in the interface layer n approx 1.6 x 10 sup 2 sup 0 cm sup - sup 3 and the carriers effective mass m* approx m sub e may have the value of T sub c approx 1000 K. The obtained evaluation of the T sub c temperature corresponds by the values order to the experimental value

  15. The influence of dietary Cu and diabetes on tissue sup 67 Cu retention kinetics in rats

    Energy Technology Data Exchange (ETDEWEB)

    Uriu-Hare, J.Y.; Rucker, R.B.; Keen, C.L. (Univ. of California, Davis (United States))

    1991-03-11

    Compared to controls, diabetes results in higher plasma, liver and kidney Cu concentrations. Since alterations in Cu metabolism may be associated with diabetic pathology, the authors investigated how Cu metabolism is affected by diabetes and dietary Cu intake. Nondiabetic and STZ diabetic rats were fed Cu suppl. or Cu def. diets for 5 wks. Rats were intubated with 28 {mu}Ci {sup 67}Cu and killed after 8, 16, 24, 32, 64, or 128 h. There were marked effects of both diet and diabetes on {sup 67}Cu metabolism. Independent of diabetes, deficient rats had a higher % of retained {sup 67}Cu, in liver, plasma, RBC, muscle, spleen, brain, lung, uterus, and intestine than adequate Cu rats. Independent of dietary Cu, diabetic rats had a lower % of retained {sup 67}Cu in liver, plasma, RBC, muscle, spleen, lung, bone, pancreas, skin, uterus and heart than controls. Differential effects were noted for kidney; adequate Cu diabetic rats had a higher % of retained {sup 67}Cu than all other groups. Marked effects of both diet and diabetes were evident when tissue Cu turnover was examined. Compared to Cu suppl. rats, Cu def. rats had a slower turnover of {sup 67}Cu, in liver, plasma, intestine, pancreas, eye, brain, muscle, spleen, lung and heart. Diabetic rats had a slower turnover of {sup 67}Cu than nondiabetic rats in liver, plasma, intestine, pancreas, eye, kidney, RBC and uterus. The data imply that a focus on Cu metabolism with regard to cellular Cu trafficking and pathology may be warranted.

  16. Preparation of catalysts PtSb{sub 2}O{sub 5}.SnO{sub 2} supported on carbon and ATO using the alcohol reduction method for electrochemical oxidation of ethanol; Preparacao de eletrocatalisadores PtSb{sub 2}O{sub 5}.SnO{sub 2} suportados em carbono e ATO pelo metodo da reducao por alcool para oxidacao eletroquimica do etanol

    Energy Technology Data Exchange (ETDEWEB)

    Ayoub, Jamil Mahmoud Said

    2013-06-01

    Pt Sn/C-ATO electrocatalysts with different Pt:Sn atomic ratios (90:10, 70:30 and 50:50) were prepared in a single step by an alcohol-reduction process using H{sub 2}PtCl{sub 6}.6H{sub 2}O and SnCl{sub 2}.2H{sub 2}O as metal sources and ethylene glycol as solvent and reducing agent and a physical mixture of carbon Vulcan XC72 (85 wt%) and Sb{sub 2}O{sub 5}.SnO{sub 2} (15 wt%) as support (C-ATO). The obtained materials were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The catalytic activity for ethanol electro-oxidation in acid medium was investigated by cyclic voltammetry and chronoamperometry and in single direct ethanol fuel cell (DEFC). XRD analyses showed that Pt(FCC), SnO{sub 2}, carbon and ATO phases coexist in the obtained materials. The electrochemical studies showed that PtSn/C-ATO electrocatalysts were more active for ethanol electro-oxidation than PtSn/C electrocatalyst. The experiments at 100 deg C on a single DEFC showed that the power density of the cell using Pt Sn/C-ATO (90:10) was nearly 100% higher than the one obtained using Pt Sn/C (50:50). FTIR measurements showed that the addition of ATO to Pt Sn/C favors the formation of acetic acid as a product while for PtSn/C acetaldehyde was the principal product formed. (author)

  17. Performance PtSnRh electrocatalysts supported on carbon-Sb{sub 2}O{sub 5}.SbO{sub 2} for the electro-oxidation of ethanol, prepared by an alcohol-reduction process; Desempenho de eletrocatalisadores PtSnRh suportados em carbono-Sb{sub 2}O{sub 5}.SnO{sub 2} para a oxidacao eletroquimica do etanol, preparados pelo metodo de reducao por alcool

    Energy Technology Data Exchange (ETDEWEB)

    Castro, Jose Carlos

    2013-07-01

    PtSnRh electrocatalysts supported on carbon-Sb{sub 2}O{sub 5}.SnO{sub 2}, with metal loading of 20 wt%, were prepared by an alcohol-reduction process, using H{sub 2}PtCl{sub 6}.6H{sub 2}O (Aldrich), RhCl{sub 3}.xH{sub 2}O (Aldrich) and SnCl{sub 2}.2H{sub 2}O (Aldrich), as source of metals; Sb{sub 2}O{sub 5}.SnO{sub 2} (ATO) and carbon Vulcan XC72, as support; and ethylene glycol as reducing agent. The electrocatalysts obtained were characterized physically by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The diffractograms showed which PtSnRh/C-ATO electrocatalysts had FCC structure of Pt and Pt alloys, besides several peaks associated with SnO{sub 2} and ATO. The average sizes of crystallites were between 2 and 4 nm. TEM micrographs showed a good distribution of the nanoparticles on the support. The average sizes of particles were between 2 and 3 nm, with good agreement for the average size of the crystallites. The performances of the electrocatalysts were analyzed by electrochemical techniques and in real conditions of operation using single direct ethanol fuel cell. In the chronoamperometry at 50 deg C, the electrocatalysts with carbon (85 wt%) and ATO (15 wt%) support, showed the best activity, and the atomic proportions which achieved the best results were PtSnRh(70:25:05) e (90:05:05). PtSnRh(70:25:05)/85C+15ATO electrocatalysts showed the best performance in a direct ethanol fuel cell. (author)

  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. 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.

  20. Cu metabolism in the liver.

    Science.gov (United States)

    McArdle, H J; Bingham, M J; Summer, K; Ong, T J

    1999-01-01

    This paper has, given some idea of our concepts of the processes involved in the transport of Cu across cell membranes in the liver, which we have summarised in Fig 1. Cu(II)His2 is reduced to Cu(I). This is transported across the membrane, re-oxidised, either before or after binding to glutathione (Freedman et al., 1989) or HAH1 (Klomp et al., 1997), binds to SAHH, and donates Cu(II) to the ATPase. It is very interesting that cells which are very diverse from an evolutionary point of view still use very similar methods to handle the metal. Whether regulation of transport is also the sam remains to be seen. We would guess that, although there will be strong similarities, there will also be very significant differences, reflecting the different environments seen by different tissues in mammalian cells and given the different requirements of the tissues.

  1. Cu influence on hens weight

    Science.gov (United States)

    Afonina, I. A.; Kleptsyna, E. S.; Petukhov, V. L.; Patrashkov, S. A.

    2003-05-01

    Copper plays an important part in living being bodies. But, both high and low Cu levels may cause human and animal diseases. Some East Siberia areas are characterized by Cu pollution [1]. 5 group of hens were formed: 1 - control, 2-5 - experimental. For a month the hens from experimental groups were drunk with water where Cu content was 5, 10, 20 and 30 times higher than the upper limits (UL). Group 1 - 3 hens' weight was almost the same during the experiment. Weight decrease (from 2020 to 1656 g) was detected in group 4 (20 UL) for the first half a month. All the hens of group 4 except for 3 hens were died for the last 2 weeks. In group 5 (30 UL) all the hens died after 2 ... 14 days. Thus, high Cu concentrations (20 ... 30 UL) cause hens' weight reduction of and their death.

  2. Effect of grain orientations of Cu seed layers on the growth of -oriented nanotwinned Cu

    National Research Council Canada - National Science Library

    Liu, Chien-Min; Lin, Han-Wen; Lu, Chia-Ling; Chen, Chih

    2014-01-01

    .... It is found that densely-packed nanotwinned Cu (nt-Cu) can be grown by pulsed electroplating on the strong -oriented Cu seed layer without a randomly-oriented transition layer between the nt-Cu and the Cu seed layer...

  3. The Cu II Spectrum

    Directory of Open Access Journals (Sweden)

    Alexander Kramida

    2017-02-01

    Full Text Available New wavelength measurements in the vacuum ultraviolet (VUV, ultraviolet and visible spectral regions have been combined with available literature data to refine and extend the description of the spectrum of singly ionized copper (Cu II. In the VUV region, we measured 401 lines using a concave grating spectrograph and photographic plates. In the UV and visible regions, we measured 276 lines using a Fourier-transform spectrometer. These new measurements were combined with previously unpublished data from the thesis of Ross, with accurate VUV grating measurements of Kaufman and Ward, and with less accurate older measurements of Shenstone to construct a comprehensive list of ≈2440 observed lines, from which we derived a revised set of 379 optimized energy levels, complemented with 89 additional levels obtained using series formulas. Among the 379 experimental levels, 29 are new. Intensities of all lines observed in different experiments have been reduced to the same uniform scale by using newly calculated transition probabilities (A-values. We combined our calculations with published measured and calculated A-values to provide a set of 555 critically evaluated transition probabilities with estimated uncertainties, 162 of which are less than 20%.

  4. Remoção de Cu+2 de soluções aquosas em zeólita NaX: efeito da granulometria Removal of copper (II from aqueous solution on NaX zeolite: effect of particle size

    Directory of Open Access Journals (Sweden)

    Sibele B. C. Pergher

    2005-06-01

    Full Text Available The present study consists in evaluating the NaX zeolite efficiency in removing Cu2+ from aqueous solutions, for future use of NaX in removing metals from wastewaters. The experiments were performed in batch systems (with shaking and continous stirring and for different time intervals (1 to 24 h. Three particle sizes were employed: < 850 µm, 850 µm - 1 mm and 3 mm. It has been concluded that it is possible to employ the NaX zeolite for metal removal and the particle size plays an important role in the adsorption process. Specifically, NaX zeolites of smaller particle size achieved the maximum adsorption capacity of 152.36 mg of Cu2+/g of zeolite at pH = 4.5.

  5. <em>Angiostrongylus vasorumem> in red foxes (<em>Vulpes vulpesem> and badgers (<em>Meles melesem> from Central and Northern Italy

    Directory of Open Access Journals (Sweden)

    Marta Magi

    2010-06-01

    Full Text Available Abstract During 2004-2005 and 2007-2008, 189 foxes (<em>Vulpes vulpesem> and 6 badgers (<em>Meles melesem> were collected in different areas of Central Northern Italy (Piedmont, Liguria and Tuscany and examined for <em>Angiostrongylus vasorumem> infection. The prevalence of the infection was significantly different in the areas considered, with the highest values in the district of Imperia (80%, Liguria and in Montezemolo (70%, southern Piedmont; the prevalence in Tuscany was 7%. One badger collected in the area of Imperia turned out to be infected, representing the first report of the parasite in this species in Italy. Further studies are needed to evaluate the role played by fox populations as reservoirs of infection and the probability of its spreading to domestic dogs.
    Riassunto <em>Angiostrongylus vasorumem> nella volpe (<em>Vulpes vulpesem> e nel tasso (<em>Meles melesem> in Italia centro-settentrionale. Nel 2004-2005 e 2007-2008, 189 volpi (<em>Vulpes vulpesem> e 6 tassi (<em>Meles melesem> provenienti da differenti aree dell'Italia settentrionale e centrale (Piemonte, Liguria Toscana, sono stati esaminati per la ricerca di <em>Angiostrongylus vasorumem>. La prevalenza del nematode è risultata significativamente diversa nelle varie zone, con valori elevati nelle zone di Imperia (80% e di Montezemolo (70%, provincia di Cuneo; la prevalenza in Toscana è risultata del 7%. Un tasso proveniente dall'area di Imperia è risultato positivo per A. vasorum; questa è la prima segnalazione del parassita in tale specie in Italia. Ulteriori studi sono necessari per valutare il potenziale della volpe come serbatoio e la possibilità di diffusione della parassitosi ai cani domestici.

    doi:10.4404/hystrix-20.2-4442

  6. The effect of dietary Cu and diabetes on indices of Cu nutriture in the rat

    Energy Technology Data Exchange (ETDEWEB)

    Rucker, R.B.; Uriu-Hare, J.Y.; Tinker, D.; Keen, C.L. (Univ. of California, Davis (United States))

    1991-03-11

    The uptake-retention of 67Cu is affected by dietary Cu and diabetes. Consequently, the functional activities of select enzymes and tissue Cu status were assessed. STZ-diabetic and control rats were fed Cu suppl. or def. diets. Rats were gavaged with 28 {mu}Ci 67Cu, and killed 8, 16, 24, 32, 64, or 128 h later. Diabetic rats were hyperphagic, hyperglycemic and hypoinsulinemic; with no effect of diet. Plasma ceruloplasmin activity (Cp) was lower in Cu def. rats; diabetic rats tended to have higher Cp than controls. Cu def. rats had low Cu levels in liver, kidney and plasma. Cu suppl. diabetic rats had higher liver and kidney Cu compared to Cu def. diabetic rats. Gel chromatography of liver showed that with time, there was a transfer of 67Cu from low to higher MW ligands. In nondiabetic rats, more 67Cu was associated with the higher MW ligands. The converse was observed for diabetic rats. There was no effect of diabetes on liver 67Cu localization. Diabetic rats had higher metallothionein (MT) concentrations in liver and kidney compared to controls Cu deficiency lowered MT values in both diabetic and control rats. CuZn SOD Cu activity was lowered with Cu def. and diabetes, while Mn SOD activity was similar among groups. Plasma lipid peroxide levels were lower in diabetic rats than controls. The results show that Cu metabolism is affected in diabetes, and the changes are functionally significant.

  7. <em>An entem>-Kaurane-Type Diterpene in <em>Croton antisyphiliticusem> Mart.

    Directory of Open Access Journals (Sweden)

    Ana Maria Pereira

    2012-07-01

    Full Text Available <em>Croton antisyphiliticus em>is a medicinal plant widely used in the treatment of microbial infections, especially those affecting the genital tract. Crude extract, fractions and pure compound isolated from roots of this species were investigated to validate their antimicrobial activity against <em>Escherichia coliem> and <em>Staphylococcus aureusem>. The compound <em>ent>-kaur-16-en-18-oic acid was isolated as a major component (0.7% of crude extract, and its MIC value determined against <em>S. aureusem> (ATCC 6538 was 250 μg/mL. This is the first phytochemical work on the species monitored with antimicrobial assay.

  8. Phonon spectral densities of Cu surfaces: Application to Cu(211)

    Science.gov (United States)

    Mărinică, M.-C.; Raşeev, G.; Smirnov, K. S.

    2001-05-01

    Power phonon spectra of vicinal stepped surfaces of Cu(211) have been calculated using a molecular dynamics method combined with a semiempirical potential. The potential is based on an analytic form of inverse powers proposed by Finnis and Sinclair with the parametrization of Sutton and Chen. One of the four independent parameters of the potential was rescaled to reproduce the bulk phonon spectrum of Cu while retaining other properties of the bulk Cu close to the experimental values. Using this potential, we calculated the power surface phonon spectra, projection of the spectra at the high-symmetry points of surface Brillouin zone (SBZ), and the mean square displacements (MSD's) of atoms of the Cu(211) surface. The calculated projected phonon spectra at Γ¯ and at two new SBZ points (at X¯ and Y¯) compare favorably with experiment and theory when available. The MSD of the Cu(211) surface is also well reproduced and its temperature dependence shows that anharmonicity of the atomic motion becomes important above 200 K.

  9. 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.

  10. Speciation of Cu in MSWI bottom ash and its relation to Cu leaching

    Energy Technology Data Exchange (ETDEWEB)

    Arickx, S. [Department of Chemical Engineering, Katholieke Universiteit Leuven, W. de Croylaan 46, B-3001 Leuven (Belgium)], E-mail: stefanie.arickx@telenet.be; Gerven, T. van [Department of Chemical Engineering, Katholieke Universiteit Leuven, W. de Croylaan 46, B-3001 Leuven (Belgium); Boydens, E.; L' Hoest, P.; Blanpain, B. [Department of Metallurgy and Materials Engineering, Katholieke Universiteit Leuven, Kasteelpark Arenberg 44, B-3001 Leuven (Belgium); Vandecasteele, C. [Department of Chemical Engineering, Katholieke Universiteit Leuven, W. de Croylaan 46, B-3001 Leuven (Belgium)], E-mail: carlo.vandecasteele@cit.kuleuven.be

    2008-12-15

    In Flanders, recycling of bottom ash is mainly inhibited by the high leaching of Cu. Although it has been proved that dissolved organic C plays a major role in the Cu leaching, the possible role of inorganic Cu mineral speciation has never been experimentally examined. In this study the speciation of Cu is investigated using a combination of optical microscopy and electron microprobe -WDX/EDX. Several Cu species were determined. Metallic Cu (with or without an oxide shell), CuO and Cu{sub 2}O were the most abundant. These particles were most likely present in wire-like structures. Copper also occurred as alloy (brass, bronze, zamak), and was found frequently together with typical elements such as Ca, Cl and S. Finally, small metallic Cu particles seemed to be trapped in or precipitated on oxides and silicates. Based on this Cu speciation study, pure Cu minerals were selected and leached as a function of time. The solubility after equilibrium of all studied Cu minerals never exceeded 20 {mu}g/L (which equals 10% of the total Cu leaching). The effect of heating (2 h at 400 deg. C) on the speciation of Cu was investigated using the same combination of techniques. Results show that metallic Cu seemed to be converted to Cu oxide (mostly CuO) and that the particles were more porous after heating. These conclusions were verified by XRD analysis of the heated pure Cu minerals. After heating, the Cu minerals were also leached as a function of time, to study the impact on Cu leaching. Results indicate that their leaching had slightly increased in comparison with the non-heated Cu minerals. However, the major decrease in Cu leaching in heated bottom ash, more than neutralizes this effect and thus can be attributed to the destruction of organic matter and not to the (small) change in Cu speciation.

  11. Pesquisando em fontes visuais

    OpenAIRE

    Proença, Caio Carvalho; FFCH

    2012-01-01

    O presente ensaio pretende demonstrar reflexões sobre os usos da fotografia como fonte. Na primeira parte do ensaio procura-se demonstrar a experiência de um primeiro contato com a fonte visual, em especial a fotografia, para posteriormente entrar em contato com as diferentes formas metodológicas presente na pesquisa desta fonte. Em um segundo momento mostra-se alguns apontamentos sobre o método de pesquisa voltado à fonte visual fotográfica que auxiliam a pesquisa, contemplando a discussão s...

  12. Meteorologia em linha

    OpenAIRE

    2015-01-01

    DISPOSITIVO TÉCNICO-PEDAGÓGICO: CURSO DE METEOROLOGIA EM LINHA. Designamos por curso o sistema que resulta da relação entre um conjunto de componentes, dando unidade e identidade ao mesmo, incorporados na plataforma Versal: conjunto de 30 lições em vídeo, recursos complementares, valorização e contextualização do curso, orientação e acompanhamento desenhados e previstos, interação com os utilizadores do curso a partir do momento da sua edição aberta em linha. (https://versal.com/c/1fzwaz/m...

  13. A hipnose em triatletas

    OpenAIRE

    Szenészi, Daniela Scharamm

    2005-01-01

    Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Filosofia e Ciências Humanas. Programa de Pós-Graduação em Psicologia. Esta pesquisa objetivou investigar em atletas de triatlon a percepção das características da visualização da prova de Ironman e os seus componentes psicofisiológicos durante o transe hipnótico. Foram estudados 7 atletas do sexo masculino em 6 sessões de hipnose. Após cada sessão foi feita uma entrevista semi-estruturada e aplicado um questionário...

  14. 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...

  15. Literatura em quadrinhos

    OpenAIRE

    Ferreira,Tânia Regina

    2015-01-01

    Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Comunicação e Expressão, Programa de Pós-Graduação em Literatura, Florianópolis, 2015. O objetivo desta tese é fazer o estudo do desfecho do romance de Lima Barreto, Triste fim de Policarpo Quaresma - (centenário de publicação em livro 1915-2015) - adaptado para as quatro versões homônimas em quadrinhos por: Edgar Vasques e Flávio Braga (Desiderata, 2010); Cesar Lobo e Luiz Antonio Aguiar (Ática, 2010); Lailson de Holanda...

  16. Melhores medicamentos em Pediatria

    OpenAIRE

    2014-01-01

    Resumo: Existem actualmente muitos medicamentos que são utilizados em crianças sem terem sido suficientemente estudados nas diferentes sub-populações pediátricas, com consequências preocupantes. O reconhecimento deste facto levou à criação de regras específicas na investigação de medicamentos pediátricos nos EUA, já em 1997. De igual forma, o Regulamento de Medicamentos para Uso Pediátrico aprovado em De zembro de 2006 pelo Parlamento Europeu, tem como objectivo a resolução deste problema no ...

  17. Structural and magnetic phase transitions in CeCu6-xTx (T=Ag,em'/>Pd)

    Energy Technology Data Exchange (ETDEWEB)

    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.

    2015-12-15

    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 (Pnma) to a monoclinic (P21/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.

  18. Forças de Corte Geradas por Torneamento um Estudo de Caso das Ligas Cu-Al-Be e Cu-Al-Be-Nb-Ni Passíveis do Efeito Memória de Forma

    OpenAIRE

    2014-01-01

    As ligas com memória de forma, mais especificamente as constituídas de CuAlBe, têm desempenhado um papel importante na fabricação de componentes eletromecânicos, sobretudo quando trabalhados a partir de solicitações térmicas e/ou tensões aplicadas. A princípio, neste presente trabalho de pesquisa, foram obtidas, por fundição a gás, amostras das ligas Cu-11,8%Al-0,60%Be; Cu-11,8%Al-0,55%Be; Cu-11,8%Al-0,55%Be-0,50%Nb-0,27%Ni (% em peso). Sequencialmente, temperou-se a metade delas, com o intui...

  19. Characterization of <em>Erysiphe necatorem>-Responsive Genes in Chinese Wild <em>Vitis> <em>quinquangularis>

    Directory of Open Access Journals (Sweden)

    Xiping Wang

    2012-09-01

    Full Text Available Powdery mildew (PM, caused by fungus <em>Erysiphe necatorem>, is one of the most devastating diseases of grapevine. To better understand grapevine-PM interaction and provide candidate resources for grapevine breeding, a suppression subtractive hybridization (SSH cDNA library was constructed from <em>E. necatorem>-infected leaves of a resistant Chinese wild <em>Vitis quinquangularisem> clone “Shang-24”. A total of 492 high quality expressed sequence tags (ESTs were obtained and assembled into 266 unigenes. Gene ontology (GO analysis indicated that 188 unigenes could be assigned with at least one GO term in the biological process category, and 176 in the molecular function category. Sequence analysis showed that a large number of these genes were homologous to those involved in defense responses. Genes involved in metabolism, photosynthesis, transport and signal transduction were also enriched in the library. Expression analysis of 13 selected genes by qRT-PCR revealed that most were induced more quickly and intensely in the resistant material “Shang-24” than in the sensitive <em>V. pseudoreticulata em>clone “Hunan-1” by<em> E. necatorem> infection. The ESTs reported here provide new clues to understand the disease-resistance mechanism in Chinese wild grapevine species and may enable us to investigate <em>E. necatorem>-responsive genes involved in PM resistance in grapevine germplasm.

  20. Do Sensível ao Inteligível: novos rumos comunicacionais em saúde por meio do estudo da Teoria Quântica De lo sensible a lo inteligible: nuevas maneras de comunicación en salud a través del estudio de la Teoría Cuántica From sensitive to intelligible: new communicational ways in healthcare with the study of Quantum Theory

    Directory of Open Access Journals (Sweden)

    Ramon Moraes Penha

    2009-03-01

    Full Text Available Este estudo se propõe a apresentar uma reflexão teórica sobre a relação entre os conceitos de Ser Humano, saúde e doença, e as perspectivas advindas com o desenvolvimento da Teoria Quântica. Apresenta argumentos para a compreensão de que a partir do momento em que há o reconhecimento da dimensão espiritual, existe a necessidade de reformulações dos conceitos que norteiam a prática profissional, uma vez que são estes que possibilitam a interpretação e direcionam a resposta comunicacional que, no caso da saúde, resulta no atendimento ao doente. Entende como imperativa a necessidade, para o atendimento e compreensão da dimensão espiritual do Ser Humano, do aprofundamento do nível comunicacional que exercemos com as pessoas.Este estudio se propone presentar una reflexión teórica sobre la relación entre los conceptos de Ser Humano, salud y enfermedad, y las perspectivas provenientes del desarrollo de la Teoría Cuántica. Presenta argumentos para la comprensión de que a partir del momento en que se reconoce la dimensión espiritual, existe la necesidad de realizar reformulaciones de los conceptos que orientan la práctica profesional, una vez que son estos los que posibilitan la interpretación y dirigen la respuesta de comunicación que, en el caso de la salud, resulta en la atención al enfermo. Entiende como imperativa la necesidad de atender y comprender la dimensión espiritual del Ser Humano y, de profundizar el nivel de comunicación que ejercemos con las personas.The purpose of this study is to present a theoretical reflection about the relation between the Human Being, health and disease concepts, and the perspectives stemming from the development of the Quantum Theory. It presents arguments for the comprehension that, from the moment where the spiritual dimension is recognized, there is the need for reformulation of concepts that guide the professional practice, since they make interpretation possible and direct the

  1. Synthesis, Reactions and Evaluation of the Antimicrobial Activity of Some 4-(<em>p>-Halophenyl-4<em>H>-naphthopyran, Pyranopyrimidine and Pyranotriazolopyrimidine Derivatives

    Directory of Open Access Journals (Sweden)

    Ashraf H. F. Abd El-Wahab

    2012-07-01

    Full Text Available A series of naphthopyran derivatives 3a–f were prepared. Reaction of <em>2-em>amino-4-(<em>p>-chlorophenyl-7-methoxy-4<em>H>-naphtho[2,1-<em>b>]pyran-3-carbonitrile (3b with Ac2O afforded two products, 2-acetylamino-7-methoxy-4-(<em>p>-chlorophenyl-4<em>H>-naphtho-[2,1-<em>b>]pyran-3-carbonitrile (4 and 10,11-dihydro-3-methoxy-9-methyl-12-(<em>p>-chloro-phenyl-12<em>H>-naphtho[2,1-<em>b>]pyran[2,3-<em>d>]pyrimidine-11-one (5 and treatment of 3b with benzoyl chloride gave the pyranopyrimidin-11-one derivative 6. While treatment of 3b with formamide afforded 11-amino-3-methoxy-12-(<em>p>-chlorophenyl-12<em>H>-naphtho[2,1-<em>b>]pyrano[2,3-<em>d>]pyrimidine (7. Reaction of 3b with triethyl orthoformate gave the corresponding 2-ethoxymethyleneamino-7-methoxy-4-(<em>p>-chlorophenyl-4<em>H>-naphtho-[2,1-<em>b>]pyran-3-carbonitrile (8. Hydrazinolysis of 8 in EtOH at room temperature yielded 10-amino-10,11-dihydro-11-imino-3-methoxy-12-(<em>p>-chlorophenyl-12<em>H>-naphtho[2,1-b]pyrano-[2,3-d]pyrimidine (9, while aminolysis of 8 with methylamine or dimethylamine gave the corresponding pyranopyrimidine and <em>N,N>-dimethylaminomethylene derivatives 10 and 11. Condensation of 9 with some carboxylic acid derivatives afforded triazolopyrimidine derivatives 12–16, while reaction of 9 with benzaldehyde gave 10-benzalamino-10,11-dihydro-11-imino-3-methoxy-12-(<em>p>-chlorophenyl12<em>H>-naphtho[2,1-<em>b>]pyrano[2,3-<em>d>]pyrimidine (17. The structures of the newly synthesized compounds were confirmed by spectral data. The

  2. Microfluidic reactor synthesis and photocatalytic behavior of Cu@Cu{sub 2}O nanocomposite

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Lei, E-mail: xulei_kmust@aliyun.com [National Local Joint Laboratory of Engineering Application of Microwave Energy and Equipment Technology, Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093 (China); Mechanical Engineering, University of Washington, Seattle, WA 98195 (United States); Srinivasakannan, C. [Chemical Engineering Program, The Petroleum Institute, PO Box 253, Abu Dhabi (United Arab Emirates); Peng, Jinhui, E-mail: jhpeng@kmust.edu.cn [National Local Joint Laboratory of Engineering Application of Microwave Energy and Equipment Technology, Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093 (China); Yan, Mi [Faculty of Mathematical and Physical Sciences, University College London, London WC1E 6BT (United Kingdom); Zhang, Di [Mechanical Engineering, University of Washington, Seattle, WA 98195 (United States); Zhang, Libo [National Local Joint Laboratory of Engineering Application of Microwave Energy and Equipment Technology, Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093 (China)

    2015-03-15

    Highlights: • The Cu@Cu{sub 2}O nanocomposites were synthesized in microfluidic reactor followed by oxidation process. • The Cu@Cu{sub 2}O composite particle is on nanoscale exhibiting an open bicontinuous structure. • The amount of Cu{sub 2}O can be controlled by varying drying temperature. • The binary Cu@Cu{sub 2}O–H{sub 2}O{sub 2} systems exhibit an excellent photocatalyst for degradation methylene blue under UV irradiation. - Abstract: The Cu@Cu{sub 2}O nanocomposites were synthesized by solution-phase synthesis of Cu nanoparticles in microfluidic reactor at room temperature, followed by controlling the oxidation process. The size, morphology, elemental compositions, and the chemical composition on the surface of Cu@Cu{sub 2}O nanocomposite were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). Experimental results demonstrated that the surface of the Cu nanoparticles was oxidized to Cu{sub 2}O which serves as the shell of nanoparticle. The amount of Cu{sub 2}O can be controlled by varying the drying temperature. Additionally the binary Cu@Cu{sub 2}O nanocomposite along with H{sub 2}O{sub 2} exhibited its potential as an excellent photocatalyst for degradation of methylene blue (MB) under UV irradiation.

  3. Facile Synthesis of Colored and Conducting CuSCN Composite Coated with CuS Nanoparticles

    Science.gov (United States)

    Premalal, E. V. A.; Kannangara, Yasun Y.; Ratnayake, S. P.; Nalin de Silva, K. M.

    2017-08-01

    Conductivity-tunable, different colored CuS nanoparticle-coated CuSCN composites were synthesized in a single pot using a mixture of copper sulfate and sodium thiosulfate in the presence of triethyl amine hydrothiocyanate (THT) at the ambient condition. When these reagents are mixed in 1:1:1 molar ratio, white-gray-colored CuSCN was produced. In the absence of THT, microsized dark blue-colored CuS particles were produced. However, when THT is present in the solution mixture by different amounts, colored conducting CuS nanoparticle-coated CuSCN composite was produced. CuS nanoparticles are not deposited on CuSCN soon after mixing these regents, but it takes nearly overnight to see the color change (CuS production) in the white CuSCN dispersed mixture. TEM analysis shows that composite consists of hexagonal CuS nanoparticles in the range of 3-10 nm in size. It is interesting to note that CuS-coated CuSCN possesses higher conductivity than neat CuS or CuSCN. Moreover, strong IR absorption was observed for CuS-coated CuSCN composite compared to neat CuS (absence of THT) or CuSCN. Lowest resistivity of 0.05 Ω cm was observed for annealed (250 °C) CuS-coated CuSCN particles (adding 10 ml of THT) under nitrogen atmosphere. Also, this simple method could be extended to be used in the synthesis of CuS-coated composites on the other nanomaterials such as metal oxides, polymers, and metal nanoparticles.

  4. 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...... exist, however, especially within the ground and air ambulance service, and the EMS systems face several challenges. Main problems and challenges emphasized by the authors are: (1) Denmark: the dispatch centres are presently not under medical control and are without a national criteria based system....... 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...

  5. Cu/Cu2O/CuO nanoparticles: Novel synthesis by exploding wire technique and extensive characterization

    Science.gov (United States)

    Sahai, Anshuman; Goswami, Navendu; Kaushik, S. D.; Tripathi, Shilpa

    2016-12-01

    In this article, we explore potential of Exploding Wire Technique (EWT) to synthesize the copper nanoparticles using the copper metal in a plate and wire geometry. Rietveld refinement of X-ray diffraction (XRD) pattern of prepared material indicates presence of mixed phases of copper (Cu) and copper oxide (Cu2O). Agglomerates of copper and copper oxide comprised of ∼20 nm average size nanoparticles observed through high resolution transmission electron microscope (HRTEM) and energy dispersive x-ray (EDX) spectroscopy. Micro-Raman (μR) and Fourier transform infrared (FTIR) spectroscopies of prepared nanoparticles reveal existence of additional minority CuO phase, not determined earlier through XRD and TEM analysis. μR investigations vividly reveal cubic Cu2O and monoclinic CuO phases based on the difference of space group symmetries. In good agreement with μRaman analysis, FTIR stretching modes corresponding to Cu2-O and Cu-O were also distinguished. Investigations of μR and FTIR vibrational modes are in accordance and affirm concurrence of CuO phases besides predominant Cu and Cu2O phase. Quantum confinement effects along with increase of band gaps for direct and indirect optical transitions of Cu/Cu2O/CuO nanoparticles are reflected through UV-vis (UV-vis) spectroscopy. Photoluminescence (PL) spectroscopy spots the electronic levels of each phase and optical transitions processes occurring therein. Iterative X-ray photoelectron spectroscopy (XPS) fitting of core level spectra of Cu (2p3/2) and O (1s), divulges presence of Cu2+ and Cu+ in the lattice with an interesting evidence of O deficiency in the lattice structure and surface adsorption. Magnetic analysis illustrates that the prepared nanomaterial demonstrates ferromagnetic behaviour at room temperature.

  6. Electrochemical deposition and modification of Cu/Co-Cu multilayer

    Energy Technology Data Exchange (ETDEWEB)

    Uhlemann, M.; Gebert, A.; Herrich, M.; Krause, A.; Cziraki, A.; Schultz, L

    2003-09-30

    Multilayers of Cu/Co-Cu were electrodeposited from a citrate electrolyte on quartz with Au and Si substrates with a Permalloy/Cu seedlayer by means of the potentiostatic double-pulse technique simultaneously controlled by microgravimetric measurements. The influence of a superimposed magnetic field and of annealing conditions on the microstructure has been studied. When an external magnetic field is parallel-orientated toward the electrode, an increase of the Cu deposition rate was observed due to magnetohydrodynamic effects. In contrast, the deposition rate of Co decreases. Microstructural investigations have shown that both a superimposed uniform magnetic field up to 600 mT and an inhomogeneous field of an SmCo permanent magnet change the microstructure and improve the GMR effect. X-ray diffraction measurements revealed that all grains are arranged in the <1 1 1> direction in contrast to layers formed without magnetic field with only 75% of the grains having a (1 1 1) texture. Isothermal heat treatment at different temperatures increases the GMR effect corresponding to an increase of grain size with preferred (1 1 1) orientation.

  7. Preconceito em disfarce

    Directory of Open Access Journals (Sweden)

    João de Almeida

    2001-02-01

    Full Text Available

    0 presente estudo pretende analisar os significados básicos do texto "Preto e Branco", de F. Sabino, valendo-se de alguns modelos teóricos lingüísticos, principalmente de Greimas e de Pottier, em seqüência que vai da estrutura da narrativa e do percurso gerativo de sentido até as relações sêmicas, em especial.

  8. Fabricação e caracterização de termopares Cu/CuNixPy obtidos por deposição eletroquímica.

    OpenAIRE

    Fernando Trevisan Saez Parra

    2008-01-01

    Neste trabalho foram estudadas deposições químicas de ligas CuNixPy e foram fabricados termopares Cu/CuNixPy sobre superfícies de lâminas de silício. Inicialmente, as superfícies foram pré-ativadas em uma solução diluída de ácido fluorídrico contendo PdCl2. Em seguida, foi empregado um banho químico alcalino diluído em água deionizada contendo 15 g/l NiSO4.6H2O; 0,1 a 0,3 g/l CuSO4.5H2O; 15 g/l Na2HPO2.H2O e 60 g/l Na3C6H5O7.2H2O na temperatura de 80OC sendo que NH4OH foi adicionado até que o...

  9. Monitoramento da contaminação por elementos traço em ostras comercializadas em Recife, Pernambuco, Brasil

    Directory of Open Access Journals (Sweden)

    André Dias Cavalcanti

    Full Text Available Amostras de ostras comercializadas em Recife, Pernambuco, Brasil, foram monitoradas em relação ao conteúdo de elementos traço (Hg, Zn, Fe, Cu e Mn durante o período de um ano (março/2001 a fevereiro/2002. Mercúrio foi o principal contaminante encontrado nas ostras e o elemento que apresenta maior risco à saúde pública. Foram encontrados valores de concentração de Hg em ostras de até 551,12µg/kg (peso úmido. Esses valores sugerem que a ingestão de ostras deve ser feita com restrições, principalmente, pela população que vive de sua coleta como forma de subsistência, por crianças, e mulheres grávidas. A avaliação dos níveis de mercúrio em frutos do mar é um importante fator para avaliar o risco de contaminação por mercúrio em pessoas não ocupacionalmente expostas.

  10. Monitoramento da contaminação por elementos traço em ostras comercializadas em Recife, Pernambuco, Brasil

    Directory of Open Access Journals (Sweden)

    Cavalcanti André Dias

    2003-01-01

    Full Text Available Amostras de ostras comercializadas em Recife, Pernambuco, Brasil, foram monitoradas em relação ao conteúdo de elementos traço (Hg, Zn, Fe, Cu e Mn durante o período de um ano (março/2001 a fevereiro/2002. Mercúrio foi o principal contaminante encontrado nas ostras e o elemento que apresenta maior risco à saúde pública. Foram encontrados valores de concentração de Hg em ostras de até 551,12µg/kg (peso úmido. Esses valores sugerem que a ingestão de ostras deve ser feita com restrições, principalmente, pela população que vive de sua coleta como forma de subsistência, por crianças, e mulheres grávidas. A avaliação dos níveis de mercúrio em frutos do mar é um importante fator para avaliar o risco de contaminação por mercúrio em pessoas não ocupacionalmente expostas.

  11. <em>In Vitro em>and <em>in em>Vivo> Antitumor Effect of Trachylobane-360, a Diterpene from<em> Xylopia langsdorffianaem>

    Directory of Open Access Journals (Sweden)

    João Carlos Lima Rodrigues Pita

    2012-08-01

    Full Text Available Trachylobane-360 (<em>ent>-7α-acetoxytrachyloban-18-oic acid was isolated from <em>Xylopia langsdorffianaem>. Studies have shown that it has weak cytotoxic activity against tumor and non-tumor cells. This study investigated the <em>in vitroem>> em>and <em>in vivoem> antitumor effects of trachylobane-360, as well as its cytotoxicity in mouse erythrocytes. In order to evaluate the <em>in vivoem> toxicological aspects related to trachylobane-360 administration, hematological, biochemical and histopathological analyses of the treated animals were performed. The compound exhibited a concentration-dependent effect in inducing hemolysis with HC50 of 273.6 µM, and a moderate <em>in vitroem>> em>concentration-dependent inhibitory effect on the proliferation of sarcoma 180 cells with IC50 values of 150.8 µM and 150.4 µM, evaluated by the trypan blue exclusion test and MTT reduction assay, respectively. The <em>in vivoem> inhibition rates of sarcoma 180 tumor development were 45.60, 71.99 and 80.06% at doses of 12.5 and 25 mg/kg of trachylobane-360 and 25 mg/kg of 5-FU, respectively. Biochemical parameters were not altered. Leukopenia was observed after 5-FU treatment, but this effect was not seen with trachylobane-360 treatment. The histopathological analysis of liver and kidney showed that both organs were mildly affected by trachylobane-360 treatment. Trachylobane-360 showed no immunosuppressive effect. In conclusion, these data reinforce the anticancer potential of this natural diterpene.

  12. CuI Thiolate Reactivity with Dioxygen: The Formation of CuII Sulfinate and CuII Sulfonate Species via a CuII Thiolate Intermediate

    NARCIS (Netherlands)

    Ording-Wenker, E.C.M.; Siegler, M.A.M.; Lutz, M.; Bouwman, E.

    2013-01-01

    CuI(Py2NS) (1) is formed by addition of CuI to a solution of the pyridyl-thiol ligand N-(2-mercaptopropyl)- N,N-bis(2-pyridylmethyl)amine (Py2NSH). Oxidation of complex 1 by air leads to the formation of CuII sulfinate and CuII sulfonate complexes, providing a model for the oxidative degeneration of

  13. 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.

  14. Punicalagin Green Functionalized Cu/Cu2O/ZnO/CuO Nanocomposite for Potential Electrochemical Transducer and Catalyst

    Science.gov (United States)

    Fuku, X.; Kaviyarasu, K.; Matinise, N.; Maaza, M.

    2016-09-01

    A novel ternary Punica granatum L-Cu/Cu2O/CuO/ZnO nanocomposite was successfully synthesised via green route. In this work, we demonstrate that the green synthesis of metal oxides is more viable and facile compare to other methods, i.e., physical and chemical routes while presenting a potential electrode for energy applications. The prepared nanocomposite was characterised by both microscopic and spectroscopic techniques. High-resolution scanning electron microscopy (HRSEM) and X-ray diffraction (XRD) techniques revealed different transitional phases with an average nanocrystallite size of 29-20 mm. It was observed that the nanocomposites changed from amorphous-slightly crystalline Cu/Cu2O to polycrystalline Cu/Cu2O/CuO/ZnO at different calcination temperatures (room temperature-RT- 600 °C). The Cu/Cu2O/ZnO/CuO metal oxides proved to be highly crystalline and showed irregularly distributed particles with different sizes. Meanwhile, Fourier transform infrared (FTIR) spectroscopy confirmed the purity while together with ultraviolet-visible (UV-Vis) spectroscopy proved the proposed mechanism of the synthesised nanocomposite. UV-Vis showed improved catalytic activity of the prepared metal oxides, evident by narrow band gap energy. The redox and electrochemical properties of the prepared nanocomposite were achieved by cyclic voltammetry (CV), electrochemical impedance (EIS) and galvanostatic charge-discharge (GCD). The maximum specific capacitance ( C s) was calculated to be 241 F g-1 at 50 mV s-1 for Cu/Cu2O/CuO/ZnO nanoplatelets structured electrode. Moreover, all the CuO nanostructures reveal better power performance, excellent rate as well as long term cycling stability. Such a study will encourages a new design for a wide spectrum of materials for smart electronic device applications.

  15. Sulla presenza di <em>Sorex antinoriiem>, <em>Neomys anomalusem> (Insectivora, Soricidae e <em>Talpa caecaem> (Insectivora, Talpidae in Umbria

    Directory of Open Access Journals (Sweden)

    A.M. Paci

    2003-10-01

    Full Text Available Lo scopo del contributo è di fornire un aggiornamento sulla presenza del Toporagno del Vallese <em>Sorex antinoriiem>, del Toporagno acquatico di Miller <em>Neomys anomalusem> e della Talpa cieca <em>Talpa caecaem> in Umbria, dove le specie risultano accertate ormai da qualche anno. A tal fine sono stati rivisitati i reperti collezionati e la bibliografia conosciuta. Toporagno del Vallese: elevato di recente a livello di specie da Brünner et al. (2002, altrimenti considerato sottospecie del Toporagno comune (<em>S. araneus antinoriiem>. È conservato uno di tre crani incompleti (mancano mandibole ed incisivi superiori al momento prudenzialmente riferiti a <em>Sorex> cfr. <em>antinorii>, provenienti dall?Appennino umbro-marchigiano settentrionale (dintorni di Scalocchio - PG, 590 m. s.l.m. e determinati sulla base della pigmentazione rossa degli ipoconi del M1 e M2; Toporagno acquatico di Miller: tre crani (Breda in Paci e Romano op. cit. e un esemplare intero (Paci, ined. sono stati trovati a pochi chilometri di distanza gli uni dall?altro tra i comuni di Assisi e Valfabbrica, in ambienti mediocollinari limitrofi al Parco Regionale del M.te Subasio (Perugia. In provincia di Terni la specie viene segnalata da Isotti (op. cit. per i dintorni di Orvieto. Talpa cieca: sono noti una femmina e un maschio raccolti nel comune di Pietralunga (PG, rispettivamente in una conifereta a <em>Pinus nigraem> (m. 630 s.l.m. e nelle vicinanze di un bosco misto collinare a prevalenza di <em>Quercus cerrisem> (m. 640 s.l.m.. Recentemente un terzo individuo è stato rinvenuto nel comune di Sigillo (PG, all?interno del Parco Regionale di M.te Cucco, sul margine di una faggeta a 1100 m s.l.m. In entrambi i casi l?areale della specie è risultato parapatrico con quello di <em>Talpa europaeaem>.

  16. Compound Cuing in Free Recall

    Science.gov (United States)

    Lohnas, Lynn J.; Kahana, Michael J.

    2014-01-01

    According to the retrieved context theory of episodic memory, the cue for recall of an item is a weighted sum of recently activated cognitive states, including previously recalled and studied items as well as their associations. We show that this theory predicts there should be compound cuing in free recall. Specifically, the temporal contiguity…

  17. Barrier/Cu contact resistivity

    Energy Technology Data Exchange (ETDEWEB)

    Reid, J.S.; Nicolet, M.A. [California Inst. of Tech., Pasadena, CA (United States); Angyal, M.S.; Lilienfeld, D.; Shacham-Diamand, Y. [Cornell Univ., Ithaca, NY (United States); Smith, P.M. [Sandia National Labs., Albuquerque, NM (United States)

    1995-10-17

    The specific contact resistivity of Cu with ({alpha} + {beta})-Ta, TiN, {alpha}-W, and amorphous-Ta{sub 36}Si{sub 14}N{sub 50} barrier films is measured using a novel four-point-probe approach. Geometrically, the test structures consist of colinear sets of W-plugs to act as current and voltage probes that contact the bottom of a planar Cu/barrier/Cu stack. Underlying Al interconnects link the plugs to the current source and voltmeter. The center-to-center distance of the probes ranges from 3 to 200 {micro}m. Using a relation developed by Vu et al., a contact resistivity of roughly 7 {times} 10{sup {minus}9} {Omega} cm{sup 2} is obtained for all tested barrier/Cu combinations. By reflective-mode small-angle X-ray scattering, the similarity in contact resistivity among the barrier films may be related to interfacial impurities absorbed from the deposition process.

  18. 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.

  19. 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.

  20. Investigation of agglomerated Cu seed on Cu oxidation after chemical mechanical planarization

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Jeng-Yu, E-mail: jylin@ttu.edu.tw [Department of Chemical Engineering, Tatung University, Taipei 104, Taiwan (China); Chou, Shu-Wei [Department of Chemical Engineering, Tatung University, Taipei 104, Taiwan (China); Cheng, Min-Yuan [TSMC, No. 8, Li-Hsin Rd. 6, Science-Based Industrial Park, Hsinchu 300-77, Taiwan (China)

    2010-11-01

    After chemical mechanical planarization (CMP), the reason which caused the formation of Cu-oxide defects at the interface between Cu deposit and TaN barrier layer has been studied. The experimental results of atomic force microscopy, secondary ion mass spectroscopy, X-ray diffraction demonstrated that the agglomeration phenomenon was found on Cu seed in the thickness of only 10 nm, thus resulting in the electrodeposited Cu film with more abundant C impurities at Cu/TaN interface and lower (1 1 1)/(2 0 0) ratio compared to the thick one (30 nm). Therefore it caused the Cu deposit with poor corrosion resistance and then the Cu-oxide defects were easily formed after CMP. As a result, the correlation between Cu-oxide defects at the Cu/TaN interface and the agglomeration on Cu seed layer was proposed herein.

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

    Institute of Scientific and Technical Information of China (English)

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

    2003-01-01

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

  2. Ionic Conductivities of Molten CuI and AgI-CuI Mixtures

    Science.gov (United States)

    Tahara, Shuta; Shimakura, Hironori; Ohno, Satoru; Fukami, Takanori

    2017-08-01

    Ionic conductivities σ for molten CuI and AgI-CuI mixtures were measured in the temperature ranges of approximately 580-800 and 500-850 °C, respectively. The value of σ for molten CuI in the range is smaller than that for molten CuBr and CuCl. σ for molten AgI-CuI mixtures decreases with increasing CuI-concentration. The activation energies Ea for molten AgI-CuI system were determined from the analysis of temperature dependence of σ by using the by Arrhenius type equation. Ea for molten AgI-CuI gradually increase with increasing CuIconcentration.

  3. 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>.>

  4. Genetic Diversity of <em>Pinus nigraem> Arn. Populations in Southern Spain and Northern Morocco Revealed By Inter-Simple Sequence Repeat Profiles

    OpenAIRE

    Oussama Ahrazem; Benjamin Viñegla; Juan C. Linares; Lourdes Gómez-Gómez; David Candel-Perez; Tiscar, Pedro A.; Lucas-Borja, Manuel E.; Angela Rubio-Moraga

    2012-01-01

    Eight <em>Pinus nigraem> Arn. populations from Southern Spain and Northern Morocco were examined using inter-simple sequence repeat markers to characterize the genetic variability amongst populations. Pair-wise population genetic distance ranged from 0.031 to 0.283, with a mean of 0.150 between populations. The highest inter-population average distance was between PaCU from Cuenca and YeCA from Cazorla, while the lowest distance was between TaMO from Morocco and MA Sierra Mágina...

  5. Influence of Cu content on the cell biocompatibility of Ti–Cu sintered alloys

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Erlin, E-mail: zhangel@atm.neu.edu.cn [Key Lab. for Anisotropy and Texture of Materials, Education Ministry of China, Northeastern University, Shenyang 110819 (China); Jiamusi University, Jiamusi 154007 (China); Zheng, Lanlan [Jiamusi University, Jiamusi 154007 (China); Liu, Jie [Key Lab. for Anisotropy and Texture of Materials, Education Ministry of China, Northeastern University, Shenyang 110819 (China); Dept. of Prosthodontics, The Affiliated Hospital of Medical College, Qingdao University, Qingdao 266003 (China); Bai, Bing [Dept. of Prosthodontics, School of Stomatology, China Medical University, Liaoning Institute of Dental Research, Shenyang 110001 (China); Liu, Cong [Jiamusi University, Jiamusi 154007 (China)

    2015-01-01

    The cell toxicity and the cell function of Ti–Cu sintered alloys with different Cu contents (2, 5, 10 and 25 wt.%, respectively) have been investigated in comparison with commercial pure titanium in order to assess the influence of Cu content on the cell biocompatibility of the Ti–Cu alloys. The cytotoxicity was studied by examining the MG63 cell response by CCK8 assessment. The cell morphology was evaluated by acridine orange/ethidium bromide (AO/EB) fluorescence and observed under scanning electronic microscopy (SEM). The cell function was monitored by measuring the AKP activity. It has been shown by the AO/EB morphology results that the cell death on both cp-Ti sample and Ti–Cu samples is due to apoptosis rather than necrosis. Although more apoptotic cells were found on the Ti–2Cu and Ti–5Cu samples, no evidence of Cu content dependent manner of apoptosis has been found. SEM observation indicated very good cell adhesion and spread on the cp-Ti sample and the Ti–Cu samples with different Cu contents. CCK8 results displayed that increase in the Cu content in Ti–Cu alloys does not bring about any difference in the cell viability. In addition, AKP test results indicated that no difference in the differentiation of MG63 was found between the cp-Ti and the Ti–Cu samples and among the Ti–Cu samples. All results indicated that Ti–Cu alloys exhibit very good cell biocompatibility and the Cu content up to 25 wt.% in the Ti–Cu alloys has no influence on the cell proliferation and differentiation. - Highlights: • The effect of Cu content on the cell biocompatibility has been investigated. • Cu content shows no influence on the cell proliferation. • Cu content shows no effect on the cell differentiation.

  6. Vacancy defects in epitaxial thin film CuGaSe2 and CuInSe2

    OpenAIRE

    Korhonen, E.; Kuitunen, K.; Tuomisto, Filip; Urbaniak, A.; Igalson, M.; Larsen, J.; Gutay, L; Siebentritt, S; Tomm, Y.

    2012-01-01

    Epitaxial thin film CuGaSe2 and CuInSe2 samples grown on GaAs substrates with varying [Cu]/[Ga,In] ratios were studied using positron annihilation Doppler-broadening spectroscopy and were compared to bulk crystals. We find both Cu monovacancies and Cu-Se divacancies in CuInSe2, whereas, in CuGaSe2, the only observed vacancy defect is the Cu-Se divacancy. Peer reviewed

  7. Turismo e imaginário : o percurso histórico do chocolate em Gramado/RS

    OpenAIRE

    Vargas, Daniela Pereira de

    2013-01-01

    O chocolate é um alimento largamente consumido em muitos países, tanto em climas quentes como frios, na forma líquida ou sólida. A sua história remonta aos povos pré-colombianos, mas, em 1527, as sementes de cacau foram levadas para a Europa. No século XIX há a criação de equipamentos para melhorar o aspecto visual e o sabor do chocolate e a abertura, na Europa, das primeiras indústrias produtoras de chocolate. No Brasil, as primeiras fábricas foram inauguradas no final do sécu...

  8. Distribution of visual attention within a cued area: evidence based on temporal order judgments Distribuição da atenção visual dentro de áreas indicadas: evidência baseada em julgamentos de ordem temporal

    Directory of Open Access Journals (Sweden)

    Mikael Cavallet

    2011-01-01

    Full Text Available Three experiments were performed to investigate the distribution of attention across the visual field and the possibility of attentional resources to be more concentrated inside an abrupt onset frame (cue. The participants performed a temporal order judgment task of two letters presented in sequence; one letter presented inside and the other outside the frame. The results showed that the information presented inside the frame had its perceptual latency shortened in relation to the information presented outside the frame in experimental conditions where the frame orientation, the distance between the two letters and the cue onset time were manipulated. The advantage of the information presented inside the frame was attributed to the displacement of attention to the area delimited by the frame. The results contribute to the understanding of visual perception, showing that attentional resources may be redistributed inside the borders of a geometric figure.Três experimentos foram realizados para investigar a distribuição da atenção pelo campo visual e a possibilidade dos recursos de atenção serem mais concentrados no interior de uma moldura (dica de início abrupto. Os participantes realizaram uma tarefa de julgamento de ordem temporal de duas letras apresentadas em seqüência; uma letra apresentada dentro e a outra fora da moldura. Os resultados mostraram que a informação apresentada dentro da moldura teve a sua latência perceptual encurtada em relação à informação apresentada fora da moldura em condições experimentais onde a orientação da moldura, a distância entre as duas letras e o tempo de exposição da moldura foram manipulados. Esta vantagem para a informação apresentada dentro da moldura foi atribuída ao deslocamento da atenção para a área delimitada pela moldura. Os resultados contribuem para o entendimento da percepção visual, mostrando que recursos de atenção podem ser redistribuídos dentro das bordas de

  9. 电迁移对Ni/Sn3.0Ag0.5Cu/Cu焊点界面反应的影响%EFFECT OF ELECTROMIGRATION ON INTERFACIAL REACTION IN Ni/Sn3.0Ag0.5Cu/Cu FLIP CHIP SOLDER JOINTS

    Institute of Scientific and Technical Information of China (English)

    黄明亮; 陈雷达; 周少明

    2012-01-01

    The effect of electromigration (EM) on the interfacial reaction in Ni/Sn3.0Ag0.5Cu/Cu solder joints was investigated under a current density of 5.0 ×l03 A/cm2 at 150 ℃ All solder joints were aged at 150 ℃ for comparison purpose. It has been found that the (Cu,Ni)6Sn5 intermetallic compounds (IMCs) form at both soIder/Ni and solder/Cu interfaces in the as-reflowed state. During aging at 150 ℃, the thickness of interfacial IMC increases with increasing aging time, and no interfacial IMC transformation occurs even after aging for 800 h. The flowing direction of electrons plays an important role in Cu consumption. When electrons flow from printed circuit board (PCB) to chip, the current crowding effect induces a rapid and localized dissolution of Cu pad on PCB and a formation of microcrack at the Sn3.0Ag0.5Cu/(Cu, Ni)6Sn5 interface. The dissolved Cu atoms are driven towards anode by EM, and a large amount of Cu6Sn5 IMC particles form in solder matrix along the flowing direction of electrons. When electrons flow from chip to PCB, no obvious consumption of Ni underbump metallogy (UBM) has been observed and few Cu6Sn5 IMC particles form in solder matrix near the anode interface. There is no evidence of failure induced by EM in solder joints even after EM for 800 h. To sum up, EM enhances the growth of interfacial (Cu, Ni)6Sn5 at anode side, no matter how the direction of electrons is. The interfacial IMC at anode side is thicker than that at cathode side. The Ni/Sn3.0Ag0.5Cu/Cu solder joint is prone to fail when electrons flowing from Cu to Ni.%研究了温度为150℃,电流密度为5.0×103 A/cm2的条件下电迁移对Ni/Sn3.0Ag0.5Cu/Cu焊点界面反应的影响.回流焊后在Sn3.0Ag0.5Cu/Ni和Sn3.0Ag0.5Cu/Cu的界面上均形成了(Cu,Ni)6Sn5型化合物.时效过程中界面化合物随时效时间增加而增厚,时效800 h后两端的化合物并没有发生转变,仍为(Cu,Ni)6Sn5型.电流方向对Cu基板的消耗起着决定作用.当电子从基板

  10. Dessulfurização oxidativa do dibenzotiofeno catalisada por V2O5 suportado

    OpenAIRE

    Débora Gomes Baptista Dionizio

    2014-01-01

    A necessidade de redução da emissão de poluentes, visando diminuir os sérios problemas de poluição atmosférica enfrentados atualmente, é hoje uma das principais preocupações mundiais, provocando o surgimento de leis mais rígidas, que restringem o teor de enxofre na gasolina e no diesel. Assim, o desenvolvimento de tecnologias mais eficazes na remoção de enxofre nestes combustíveis tem recebido atenção crescente. Estas tecnologias incluem a extração física com solvente, a adsorção seletiva, pr...

  11. Synthesis of catalysts supported in {gamma}-alumina; Sintese de catalisadores suportados na {gamma}-alumina

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Luiza Gabriel; Silva, A.J.N.; Santos, I.M.G.; Souza, A.G. [Paraiba Univ, Joao Pessoa, PB (Brazil). Dept. de Quimica. Lab. de Termoquimica e Materiais]. E-mail: luizagaby@yahoo.com.br; Fernandes Junior, V.J.; Araujo, A.S. [Rio Grande do Norte Univ., Natal, RN (Brazil). Dept. de Quimica. Lab. de Combustiveis

    2003-07-01

    Fuels contain a great amount of undesirable pollutants as asphaltenes, metals, sulfides and nitrogen compounds. The content of sulfur in petroleum is around 1%,. When burned, fuels liberate SO{sub x}, the greatest air pollutant . The maximum sulfur quantity in diesel is {approx}350 wppm, but in agreement to European specifications, this content will fall to 50 wppm up to 2005. To remove this sulfur a deep hydrodesulfurization is necessary, requiring high performance catalysts. This way, in this work, the following catalysts were synthesized, using Pechini method: MoO{sub 3} containing Ni and/or Co supported on {gamma}-alumina, with the formulas Co{sub x}Mo{sub 1-x}O{sub 3}/Al{sub 2}O{sub 3}, Ni{sub x}Mo{sub 1-x}O{sub 3}/Al{sub 2}O{sub 3} and Ni{sub x/2}Co{sub x/2}Mo{sub 1-x}O{sub 3}/Al{sub 2}O{sub 3} where x 0,01, 0,02 and 0,03 in mol percentage. This method was proposed, due to its high stoichiometry control, purity, reproducibility and homogeneity. All catalysts were submitted to thermal treatment at 500 deg C to 700 deg C and characterized by thermogravimetry, infrared spectroscopy, X-ray diffraction. Results indicate the stabilization of the requested composition at around 622 deg C. The X-ray diffraction results indicate that secondary phase increases with dopant amount. (author)

  12. On Cu diffusion in ZnO

    Energy Technology Data Exchange (ETDEWEB)

    Herklotz, F.; Lavrov, E.V.; Weber, J. [Technische Universitaet Dresden (Germany)

    2009-07-01

    Copper in ZnO is of special interest since recent theoretical and experimental studies found ferromagnetic behavior of ZnO:Cu at room temperature. In addition, Cu is a deep acceptor in ZnO and one of the causes of the green emission band. Experimental studies of Cu diffusion in bulk ZnO single crystals were carried out in the temperature range 1030 to 1180 C. Concentration profiles of substitutional Cu were determined via IR absorption at 5817 cm{sup -1}. Our findings reveal that the diffusion coefficient of Cu is 7.6 x 10{sup 7} exp(-4.56 eV/k{sub B}T) cm{sup 2}s{sup -1}. This is about a factor of 25 higher than reported in the earlier studies, which probed the total Cu concentration. The discrepancy is explained by the formation of Cu complexes, which occurs at high concentrations. Diffusion mechanisms are discussed.

  13. EMS in Mauritius.

    Science.gov (United States)

    Ramalanjaona, Georges; Brogan, Gerald X

    2009-02-01

    Mauritius lies in the southwest Indian Ocean about 1250 miles from the African coast and 500 miles from Madagascar. Mauritius (estimated population 1,230,602) became independent from the United Kingdom in 1968 and has one of the highest GDP per capita in Africa. Within Mauritius there is a well established EMS system with a single 999 national dispatch system. Ambulances are either publicly or privately owned. Public ambulances are run by the Government (SAMU). Megacare is a private subscriber only ambulance service. The Government has recently invested in new technology such as telemedicine to further enhance the role of EMS on the island. This article describes the current state of EMS in Mauritius and depicts its development in the context of Government effort to decentralise and modernise the healthcare system.

  14. Investigating metal removal potential by Effective Microorganisms (EM) in alginate-immobilized and free-cell forms.

    Science.gov (United States)

    Ting, Adeline Su Yien; Rahman, Nurul Hidayah Abdul; Isa, Mohamed Ikmal Hafiz Mahamad; Tan, Wei Shang

    2013-11-01

    Metal removal potential of both alginate-immobilized and free-cells of Effective Microorganisms (EM-1™ Inoculant) was investigated in this study. Results revealed that removal of Cr(III), Cu(II) and Pb(II) followed a similar trend where alginate-immobilized EM were more efficient compared to free-cells of EM. For these metals, 0.940, 2.695 and 4.011 mg g(-1) of Cr(III), Cu(II) and Pb(II) were removed compared to only 0.160, 0.859 and 0.755 mg ml(-1) removed by free-cells, respectively. The higher efficiency of alginate-immobilized EM was primarily attributed to the alginate matrix. This was evident when both alginate-immobilized EM and plain alginate beads (without EM), were not significantly different in their removal efficacies. Presence of alginate also enhanced the use of the biosorbents as maximum metal sorption was achieved after 120 min as opposed to only 60 min for free-cells. EM per se in immobilized or free-cell forms did not enhance metal removal efficacy.

  15. Construção de indicadores para avaliação de conceitos intangíveis em sistemas produtivos An approach for measurement of intangible values in production systems

    Directory of Open Access Journals (Sweden)

    Miguel Afonso Sellitto

    2004-04-01

    Full Text Available Este trabalho apresenta o desenvolvimento e a aplicação de um método para a construção de indicadores a fim de avaliar aspectos intangíveis de um sistema produtivo. Hoje em dia, principalmente nas organizações de serviços, os aspectos intangíveis têm sido usados na modelagem do sistema, no entendimento de problemas e na proposta e implementação de estratégias. A partir da teoria das medições, que se baseia na filosofia da ciência e na estatística multivariada, foi elaborada uma abordagem para a modelagem teórica dos conceitos intangíveis de um sistema produtivo. A abordagem tem início com o mapeamento teórico das variáveis não-manifestas, e continua identificando os construtos e o estado das variáveis, que pode estar relacionado a conceitos intermediários, suportados por variáveis manifestas que podem assumir formatos categóricos, a serem pesquisadas por instrumentos apropriados, como os questionários. Após essas definições, o fenômeno em estudo pode ser representado por diagramas de caminho. Se o diagrama assume forma de árvore, a regressão múltipla pode ser usada e a análise é facilitada. Se o diagrama assume forma sistêmica, incluindo relações circulares, é necessário um tratamento matemático mais complexo, que foge do escopo deste trabalho. Uma aplicação da abordagem proposta foi conduzida em quinze empresas de transporte coletivo de Porto Alegre, sendo mensurada a capacidade das empresas de apreender os conceitos de produção enxuta. Os resultados são discutidos e são apresentadas sugestões para a continuidade dos trabalhos.This paper describes the development and application of a method for developing measurements for intangible values in productive systems. Nowadays, mainly in service organizations, intangible values are been used for modeling phenomena, understanding problems, proposing and implementing strategies. From concepts presented in the measurements theory, the philosophy of

  16. Synthesis of Cu or Cu2O-polyimide nanocomposites using Cu powders and their optical properties

    Science.gov (United States)

    Choi, Dong Joo; Maeng, Ju Sung; Ahn, Key-one; Jung, Myoung Jin; Song, Seok Ho; Kim, Young-Ho

    2014-09-01

    Nanocomposites consisting of Cu or Cu2O nanoparticles in various polyimide (PI) films were successfully prepared using polyamic acid (PAA) and Cu powders. Cu powders were dissolved into PAA solutions, and the solutions were spin-coated onto the substrates. Cu or Cu2O nanoparticles were formed in PI film by curing in a reducing or inert atmosphere, respectively. The Cu nanoparticles were transformed to Cu2O nanoparticles by post-heat treatment in an oxidizing atmosphere after curing in a reducing atmosphere. Transmission electron microscopy showed that uniform, round Cu2O nanoparticles 6.0 nm in diameter were dispersed in the PI film by post-heat treatment. The addition of Cu2O nanoparticles in the 4,4‧-(hexafluoroisopropylidene)diphthalic anhydride-4,4‧-oxydianiline (6FDA-ODA) PI film enhanced the refractive index of the 6FDA-ODA PI film from 1.60 to 1.72 at 633 nm, and the transparency of the nanocomposite film was about 70-90% in the visible region and remained around 90% beyond 550 nm.

  17. Acidose ruminal em caprinos

    OpenAIRE

    Cunha, José Diogo de Oliveira e silva Ribeiro da

    2012-01-01

    Dissertação de Mestrado Integrado em Medicina Veterinária Com este trabalho pretendeu-se fazer uma revisão acerca da acidose ruminal em caprinos, visto haver pouca bibliografia sobre o tema. Este trabalho foi baseado na revisão bibliográfica de artigos científicos e completado através da observação de casos clínicos ocorridos durante o estágio curricular. O objectivo deste estudo foi realizar uma breve revisão da anatomia e fisiologia do tracto gastrointestinal dos caprinos assim com...

  18. 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 

  19. International EMS Systems

    DEFF Research Database (Denmark)

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

    2004-01-01

    exist, however, especially within the ground and air ambulance service, and the EMS systems face several challenges. Main problems and challenges emphasized by the authors are: (1) Denmark: the dispatch centres are presently not under medical control and are without a national criteria based system......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...

  20. Frenectomia em foco

    OpenAIRE

    Vieira, Joana Isabel Monteiro de Paiva

    2012-01-01

    Projeto de Pós Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Medicina Dentária O freio é uma estrutura anatómica oral classificada em freio labial (médio maxilar ou mandibular, lateral maxilar ou mandibular) ou lingual que se pode tornar num problema quando a sua inserção cria impedimentos estruturais e dificuldades a vários níveis. Um freio labial anormal pode causar algumas anomalias ou problemas, tais como u...

  1. Cyberbullying em adolescentes brasileiros

    OpenAIRE

    Wendt, Guilherme Welter

    2012-01-01

    O cyberbullying é entendido como uma forma de comportamento agressivo que ocorre através dos meios eletrônicos de interação (computadores, celulares, sites de relacionamento virtual), sendo realizado de maneira intencional por uma pessoa ou grupo contra alguém em situação desigual de poder e, ainda, com dificuldade em se defender. Os estudos disponíveis até o presente momento destacam que o cyberbullying é um fator de risco para o desenvolvimento de sintomas de ansiedade, depressão, ideação s...

  2. Corantes vitais em cromovitrectomia

    OpenAIRE

    Dib, Eduardo; Rodrigues,Eduardo Büchelle; Maia, Maurício [UNIFESP; Meyer, Carsten H; Penha, Fernando Marcondes [UNIFESP; Furlani, Bruno de Albuquerque [UNIFESP; Costa, Elaine de Paula Fiod [UNIFESP; Farah, Michel Eid

    2009-01-01

    O objetivo do artigo é apresentar os dados atuais da aplicação de corantes vitais durante cirurgia vitreorretiniana, "cromovitrectomia", bem como uma revisão da literatura atual sobre o assunto no tocante às técnicas de aplicação, indicações e complicações em cromovitrectomia. Um grande número de publicações tem abordado o perfil tóxico da indocianina verde na cromovitrectomia. Dados experimentais mostram uma toxicidade dose-dependente da mesma em várias populações de células retinianas. Nova...

  3. O recasamento em Portugal

    OpenAIRE

    Lobo, Cristina; Conceição, Cristina Palma

    2003-01-01

    Identificar tendências do fenómeno do recasamento em Portugal, nas duas últimas décadas, constitui o objectivo principal deste artigo. Para essa identificação contribuiu o conhecimento da amplitude do próprio fenómeno, isto é, a percentagem de recasamentos no total dos casamentos em Portugal, e ainda um conjunto de variáveis que permitiu conhecer a caracterização social dos protagonistas do recasamento, por um lado, e delinear a diversidade dos seus trajectos conjugais após um divórcio, por o...

  4. Frenectomia em foco

    OpenAIRE

    Vieira, Joana Isabel Monteiro de Paiva

    2012-01-01

    Projeto de Pós Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Medicina Dentária O freio é uma estrutura anatómica oral classificada em freio labial (médio maxilar ou mandibular, lateral maxilar ou mandibular) ou lingual que se pode tornar num problema quando a sua inserção cria impedimentos estruturais e dificuldades a vários níveis. Um freio labial anormal pode causar algumas anomalias ou problemas, tais como u...

  5. Acidose ruminal em caprinos

    OpenAIRE

    Cunha, José Diogo de Oliveira e silva Ribeiro da

    2012-01-01

    Dissertação de Mestrado Integrado em Medicina Veterinária Com este trabalho pretendeu-se fazer uma revisão acerca da acidose ruminal em caprinos, visto haver pouca bibliografia sobre o tema. Este trabalho foi baseado na revisão bibliográfica de artigos científicos e completado através da observação de casos clínicos ocorridos durante o estágio curricular. O objectivo deste estudo foi realizar uma breve revisão da anatomia e fisiologia do tracto gastrointestinal dos caprinos assim com...

  6. Effect of temperature on mechanical alloying of Cu-Zn and Cu-Cr system

    Institute of Scientific and Technical Information of China (English)

    ZUO Ke-sheng; XI Sheng-qi; ZHOU Jin-gen

    2009-01-01

    Cu-Zn and Cu-Cr powders were milled with an attritor mill at room temperature, -10, -20 and -30 ℃, respectively. Phase transformation and morphology evolution of the alloyed powder were investigated by X-ray diffractometry(XRD), X-ray photoelectron spectroscopy(XPS) and scanning electron microscopy(SEM). The results show that lowering temperature can delay mechanical alloying(MA) process of Cu-Zn system with negative mixing enthalpy, and promote MA process of Cu-Cr system with positive mixing enthalpy. As for Cu-Cr and Cu-Zn powders milled at -10 ℃, lamellar structures are firstly formed, while fewer lamellar particles can be found when the powder is milled at -20 ℃. When the alloyed powder is annealed at 1 000 ℃, Cu(Cr) solid solution is decomposed and Cr precipitates from Cu matrix, whereas Cu(Zn) solid solution keeps stable.

  7. Preparation of CuAlO2 and Photocatalytic Performance of Composite Catalysts%CuAlO2的合成及其复合催化剂的光催化性能

    Institute of Scientific and Technical Information of China (English)

    康园丽; 王桂赟; 刘宗园; 王延吉

    2012-01-01

    Delafossite CuA102 is prepared by thermal treatment the precursor obtained via a serai-wet method using Cu(N03)2 and A1(NO3)3 as raw material ,and oxalic acid as precipitant of copper ion under nitrogen atmosphere. The samples are characterized by thermal gravimetric analysis (TG), X-ray diffraction (XRD), ultraviolet visible diffuse reflectance(UV-Vis-DR) and transmission electron microscope(TEM). The formation process of the CuA102 is researched. With increasing the thermal treatment temperature of the precursor, firstly the CuO and Cu2O are generated, and then intermediate phase of CuAl2O4 appeared, finally no impurity phase CuA102 formed. The results shows that the synthesized CuA102 has good crystal perfection and its direct band gap is about 3.1 eV. The n-p composite photocatalysts W0rCuA102, Ti0rCuA102 and Zn0-CuA102 are prepared by precipitation composite method. The composite photocatalysts are characterized by XRD and TEM, and the photocatalytic performance of the catalysts are tested, and the results indicate that all the composite catalysts mentioned above are all made up two phases, and they all have photocatalytic activity for decomposing pure water into hydrogen under the UV-light irradiation.%以硝酸铜和硝酸铝为原料,草酸为铜离子的沉淀剂,半湿法制得前驱体,再于氮气气氛下热处理形成了铜铁矿结构的CuAlO2.对样品进行热失重(TG),X射线衍射(XRD),紫外-可见漫反射(UV-Vis-DR)及透射电镜(rEM)表征分析,探讨了CuAlO2的形成过程.结果显示,随着热处理温度的升高,含铜物质经历了由CuO、Cu2O到CuAl2O4,再到CuAlO2的变化历程;制得的CuAlO2晶体结晶完整性较好,直接禁带宽度为3.1 eV左右.用沉淀复合的方法制备出了n-p异质复合型光催化剂WO3-CuAlO2、TiO2-CuAlO2和ZnO-CuAlO2,对复合催化剂进行了XRD和TEM表征分析,并测试了复合催化剂的光催化活性.结果表明,上述催化剂均由两种物相复合而成,且在紫外光

  8. New Production Routes for Medical Isotopes 64Cu and 67Cu Using Accelerator Neutrons

    Science.gov (United States)

    Kin, Tadahiro; Nagai, Yasuki; Iwamoto, Nobuyuki; Minato, Futoshi; Iwamoto, Osamu; Hatsukawa, Yuichi; Segawa, Mariko; Harada, Hideo; Konno, Chikara; Ochiai, Kentaro; Takakura, Kosuke

    2013-03-01

    We have measured the activation cross sections producing 64Cu and 67Cu, promising medical radioisotopes for molecular imaging and radioimmunotherapy, by bombarding a natural zinc sample with 14 MeV neutrons. We estimated the production yields of 64Cu and 67Cu by fast neutrons from \\text{natC(d,n) with 40 MeV 5 mA deuterons. We used the present result together with the evaluated cross section of Zn isotopes. The calculated 64Cu yield is 1.8 TBq (175 g 64Zn) for 12 h of irradiation; the yields of 67Cu by 67Zn(n,p)67Cu and 68Zn(n,x)67Cu were 249 GBq (184 g 67Zn) and 287 GBq (186 g 68Zn) at the end of 2 days of irradiation, respectively. From the results, we proposed a new route to produce 67Cu with very little radionuclide impurity via the 68Zn(n,x)67Cu reaction, and showed the 64Zn(n,p)64Cu reaction to be a promising route to produce 64Cu. Both 67Cu and 64Cu are noted to be produced using fast neutrons.

  9. Alterações hematológicas e histopatológicas em pacu, Piaractus mesopotamicus Holmberg, 1887 (Osteichthyes, Characidae, Hematological and histopathological alteration in pacu Piaractus mesopotamicus Holmberg, 1887 (Osteichthyes, Characidae after treatment with copper sulphate (CuSO4

    Directory of Open Access Journals (Sweden)

    Flávio Ruas de Moraes

    2002-05-01

    Full Text Available Este trabalho avaliou os valores hematológicos e glicêmicos e histopatologia de Piaractus mesopotamicus (Osteichthyes, Characidae infectados com Monogenea Anacanthorus penilabiatus Boeger, Husak & Martins, 1995 (Dactylogyridae após tratamento com 0,50 mg/L e 1,00 mg/L de sulfato de cobre (CuSO4. A eficiência da droga sobre as infecções com Monogenea foi observada no primeiro dia após administração mas não após 8, 15 ou 30 dias do tratamento. As análises histopatológicas mostraram hiperplasia do epitélio e alterações circulatórias nas brânquias. No primeiro dia após tratamento, foram observadas alterações significativas (P4 mostraram redução da taxa de hemoglobina e do percentual de neutrófilos. No 8o dia do tratamento a dose de 1,00 mg/L provocou aumento da glicemia mas redução no percentual de linfócitos quando comparada com 0,50 mg/L. No 15o dia após tratamento com 1,00 mg/L os valores médios do volume corpuscular médio e o percentual de células granulocíticas especiais (C.G.E. decresceram mas o número de leucócitos totais aumentaram. No 30o dia após tratamento com 0,50 mg/L de sulfato de cobre houve aumento de C.G.E. e no tratamento com 1,00 mg/L o aumento foi de linfócitos.This paper evaluated the haematological and glycaemic parameters in Piaractus mesopotamicus (Osteichthyes, Characidae infected with Monogenea Anacanthorus penilabiatus Boeger, Husak & Martins, 1995 (Dactylogyridae after treatment with 0.50 mg/L and 1.00 mg/L of copper sulphate (CuSO4. The efficacy of the CuSO4 was observed in the first day after administration but not after eight, fifteen or thirty days. The histopathological analyses showed hyperplasia of the epithelium and circulatory changes in the gills. In the first day after treatment significant changes (Pth day. Fifteen days after 1.00 mg/L treatment, values of mean corpuscular volume (MCV and special granulocitic cells (S.G.C. percentage decreased. Nevertheless, increase of

  10. 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.

  11. Bimetallic AgCu/Cu2O hybrid for the synergetic adsorption of iodide from solution.

    Science.gov (United States)

    Mao, Ping; Liu, Ying; Liu, Xiaodong; Wang, Yuechan; Liang, Jie; Zhou, Qihang; Dai, Yuexuan; Jiao, Yan; Chen, Shouwen; Yang, Yi

    2017-08-01

    To further improve the capacity of Cu2O to absorb I(-) anions from solution, and to understand the difference between the adsorption mechanisms of Ag/Cu2O and Cu/Cu2O adsorbents, bimetallic AgCu was doped into Cu2O through a facile solvothermal route. Samples were characterized and employed to adsorb I(-) anions under different experimental conditions. The results show that the Cu content can be tuned by adding different volumes of Ag sols. After doping bimetallic AgCu, the adsorption capacity of the samples can be increased from 0.02 mmol g(-1) to 0.52 mmol g(-1). Moreover, the optimal adsorption is reached within only 240 min. Meanwhile, the difference between the adsorption mechanisms of Ag/Cu2O and Cu/Cu2O adsorbents was verified, and the cooperative adsorption mechanism of the AgCu/Cu2O hybrid was proposed and verified. In addition, the AgCu/Cu2O hybrid showed excellent selectivity, e.g., its adsorption efficiencies are 85.1%, 81.9%, 85.9% and 85.7% in the presence of the Cl(-), CO3(2-), SO4(2-) and NO3(-) competitive anions, respectively. Furthermore, the AgCu/Cu2O hybrid can worked well in other harsh environments (e.g., acidic, alkaline and seawater environments). Therefore, this study is expected to promote the development of Cu2O into a highly efficient adsorbent for the removal of iodide from solution. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Cu clustering stage before the crystallization in Fe-Si-B-Nb-Cu amorphous alloys

    DEFF Research Database (Denmark)

    Ohnuma, M.; Hono, K.; Onodera, H.

    1999-01-01

    The Cu clustering stage before the crystallization of Fe-Si-B-Nb-Cu amorphous alloys have been studied by three dimensional atom probe (3DAP) small-angle neutron scattering (SANS) and high sensitive differential calorimetry (DSC). Cu clustering occurs prior to the onset of the primary crystalliza......The Cu clustering stage before the crystallization of Fe-Si-B-Nb-Cu amorphous alloys have been studied by three dimensional atom probe (3DAP) small-angle neutron scattering (SANS) and high sensitive differential calorimetry (DSC). Cu clustering occurs prior to the onset of the primary...

  13. Lattice dynamics of La 2CuO 4 and YBa 2Cu 3O 7

    Science.gov (United States)

    Kimura, Shunji; Sota, Takayuki; Suzuki, Katsuo

    1990-08-01

    We report lattice dynamics calculations of La 2CuO 4 and YBa 2Cu 3O 7 where the mode assignment is fully performed. It is found that frequencies of the in-plane bond streching 0 vibration mode phonons are much higher than those of the bond bending 0 vibration mode phonons in La 2CuO 4 while they are close in YBa 2Cu 3O 7. The bond streching mode phonons and the bond bending mode phonons can couple to electrons near E F in YBa 2Cu 3O 7 but the latter can not in La 2CuO 4.

  14. Transition of Resistive Switching to Bidirectional Diode in Cu2O/Cu Nanowires

    Science.gov (United States)

    Kim, Deok-kee; Shin, Ho Sun; Song, Jae Yong

    2012-08-01

    Cu2O/Cu nanowires of about 2 µm length were electrodeposited within anodized aluminum oxide templates in an aqueous acidic solution using template-assisted pulse-reverse electrolysis. In the virgin state, reversible copper filaments were formed by using the copper ions driven by an electric field towards the cathode. Initially, the resistive switching dominated the electrical characteristics of the Cu2O/Cu nanowires due to the low-resistance reversible copper filaments. After the permanent breakup of the copper filaments under the high current density, the Cu2O/Cu nanowire showed bipolar exponential characteristics, which was attributed to mixed ionic and electronic conduction.

  15. Clinical Relevance of <em>CDH1em> and <em>CDH13em> DNA-Methylation in Serum of Cervical Cancer Patients

    Directory of Open Access Journals (Sweden)

    Günther K. Bonn

    2012-07-01

    Full Text Available This study was designed to investigate the DNA-methylation status of <em>E>-cadherin (<em>CDH1em> and <em>H>-cadherin (<em>CDH13em> in serum samples of cervical cancer patients and control patients with no malignant diseases and to evaluate the clinical utility of these markers. DNA-methylation status of <em>CDH1em> and <em>CDH13em> was analyzed by means of MethyLight-technology in serum samples from 49 cervical cancer patients and 40 patients with diseases other than cancer. To compare this methylation analysis with another technique, we analyzed the samples with a denaturing high performance liquid chromatography (DHPLC PCR-method. The specificity and sensitivity of <em>CDH1em> DNA-methylation measured by MethyLight was 75% and 55%, and for <em>CDH13em> DNA-methylation 95% and 10%. We identified a specificity of 92.5% and a sensitivity of only 27% for the <em>CDH1em> DHPLC-PCR analysis. Multivariate analysis showed that serum <em>CDH1em> methylation-positive patients had a 7.8-fold risk for death (95% CI: 2.2–27.7; <em>p> = 0.001 and a 92.8-fold risk for relapse (95% CI: 3.9–2207.1; <em>p> = 0.005. We concluded that the serological detection of <em>CDH1em> and <em>CDH13em> DNA-hypermethylation is not an ideal diagnostic tool due to low diagnostic specificity and sensitivity. However, it was validated that <em>CDH1em> methylation analysis in serum samples may be of potential use as a prognostic marker for cervical cancer patients.

  16. "Estudos do desenvolvimento e caracterização das ligas Cu-Ni-Pt e Cu-Ni-Sn para fins eletro-eletrônicos"

    OpenAIRE

    Luis Carlos Elias da Silva

    2006-01-01

    O Cu e suas ligas têm diferentes aplicações na sociedade moderna devido as excelentes propriedades elétricas, condutividade térmica, resistência à corrosão dentre outras propriedades. Estas aplicações podem ser em válvulas, tubulações, panelas para absorção de energia solar, radiadores para automóveis, condutores de corrente e eletrônico, elementos de termostatos e partes estruturais de reatores nucleares, como, por exemplo, bobinas para campo toroidal para um reator de fusão nuclear. Dentre ...

  17. Assignment of Cu NQR frequencies and Cu spin-spin relaxation in YBa 2Cu 3O 7-δ

    Science.gov (United States)

    Mali, M.; Roos, J.; Brinkmann, D.

    1988-06-01

    We have repeated and confirmed our previous assignment of the Cu NQR frequencies to the Cu sites 1 and 2 by measuring the intensities of the NQR signals at 31.5. and 22.05 MHz. The pulse spectrometer has been calibrated by means of the 19F NMR signal at the same frequencies. The lower Cu frequency is assigned to Cul. A point charge calculation of the electric field gradient at the Cu sites is in good agreement with experimental data. The ratio of the spin-lattice relaxation times of both Cu isotopes at either site has been determined. Unusual temperature dependences of the Cu spin-spin relaxation times have been measured.

  18. Immortality of Cu damascene interconnects

    Science.gov (United States)

    Hau-Riege, Stefan P.

    2002-04-01

    We have studied short-line effects in fully-integrated Cu damascene interconnects through electromigration experiments on lines of various lengths and embedded in different dielectric materials. We compare these results with results from analogous experiments on subtractively-etched Al-based interconnects. It is known that Al-based interconnects exhibit three different behaviors, depending on the magnitude of the product of current density, j, and line length, L: For small values of (jL), no void nucleation occurs, and the line is immortal. For intermediate values, voids nucleate, but the line does not fail because the current can flow through the higher-resistivity refractory-metal-based shunt layers. Here, the resistance of the line increases but eventually saturates, and the relative resistance increase is proportional to (jL/B), where B is the effective elastic modulus of the metallization system. For large values of (jL/B), voiding leads to an unacceptably high resistance increase, and the line is considered failed. By contrast, we observed only two regimes for Cu-based interconnects: Either the resistance of the line stays constant during the duration of the experiment, and the line is considered immortal, or the line fails due to an abrupt open-circuit failure. The absence of an intermediate regime in which the resistance saturates is due to the absence of a shunt layer that is able to support a large amount of current once voiding occurs. Since voids nucleate much more easily in Cu- than in Al-based interconnects, a small fraction of short Cu lines fails even at low current densities. It is therefore more appropriate to consider the probability of immortality in the case of Cu rather than assuming a sharp boundary between mortality and immortality. The probability of immortality decreases with increasing amount of material depleted from the cathode, which is proportional to (jL2/B) at steady state. By contrast, the immortality of Al-based interconnects is

  19. Crescimento e desenvolvimento da mandioca e do milho em cultivo solteiro e consorciado

    OpenAIRE

    Alfredo Schons

    2006-01-01

    A mandioca é um dos mais importantes alimentos para o homem e para os animais, especialmente em países pobres e emergentes. O milho (Zea mays L.) é o 3 cereal mais produzido no mundo. Na pequena propriedade familiar do Rio Grande do Sul, é freqüente o cultivo de mandioca e milho. Os objetivos dessa dissertação foram estimar o filocrono e identificar um indicador morfológico baseado no número de folhas acumuladas (NF) na haste principal para o início de acumulação de amido (IAA) em mandioca cu...

  20. Quantifying magnetic exchange in doubly-bridged Cu-X(2)-Cu (X = F, Cl, Br) chains enabled by solid state synthesis of CuF(2)(pyrazine).

    Science.gov (United States)

    Lapidus, Saul H; Manson, Jamie L; Liu, Junjie; Smith, Matthew J; Goddard, Paul; Bendix, Jesper; Topping, Craig V; Singleton, John; Dunmars, Cortney; Mitchell, J F; Schlueter, John A

    2013-05-04

    Solid state techniques involving pressure and temperature have been used to synthesize the fluoride member of the CuX(2)(pyrazine) (X = F, Cl, Br) family of coordination polymers that cannot be crystallized by solution methods. CuF(2)(pyrazine) exhibits unique trans doubly-bridged Cu-F(2)-Cu chains that provide an opportunity to quantify magnetic superexchange in an isostructural Cu-X(2)-Cu series.

  1. Facile synthesis of dendritic Cu by electroless reaction of Cu-Al alloys in multiphase solution

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ying; Liang, Shuhua, E-mail: liangxaut@gmail.com; Yang, Qing; Wang, Xianhui

    2016-11-30

    Highlights: • Nano- or micro-scale fractal dendritic copper (FDC) was synthesized by electroless immersing of Cu-Al alloys in CuCl{sub 2} + HCl. • FDC size increases with the increase of Al content in Cu-Al alloys immersed in CuCl{sub 2} + HCl solution. • Nanoscale Cu{sub 2}O was found at the edge of FDC. Nanoporous copper (NPC) can also be obtained by using Cu{sub 17}Al{sub 83} alloy. • The potential difference between CuAl{sub 2} and α-Al phase and the replacement reaction in multiphase solution are key factors. - Abstract: Two-dimensional nano- or micro-scale fractal dendritic coppers (FDCs) were synthesized by electroless immersing of Cu-Al alloys in hydrochloric acid solution containing copper chloride without any assistance of template or surfactant. The FDC size increases with the increase of Al content in Cu-Al alloys immersed in CuCl{sub 2} + HCl solution. Compared to Cu{sub 40}Al{sub 60} and Cu{sub 45}Al{sub 55} alloys, the FDC shows hierarchical distribution and homogeneous structures using Cu{sub 17}Al{sub 83} alloy as the starting alloy. The growth direction of the FDC is <110>, and all angles between the trunks and branches are 60°. Nanoscale Cu{sub 2}O was found at the edge of FDC. Interestingly, nanoporous copper (NPC) can also be obtained through Cu{sub 17}Al{sub 83} alloy. Studies showed that the formation of FDC depended on two key factors: the potential difference between CuAl{sub 2} intermetallic and α-Al phase of dual-phase Cu-Al alloys; a replacement reaction that usually occurs in multiphase solution. The electrochemical experiment further proved that the multi-branch dendritic structure is very beneficial to the proton transfer in the process of catalyzing methanol.

  2. Effect of Cu concentration on morphology of Sn-Ag-Cu solders by mechanical alloying

    Science.gov (United States)

    Kao, Szu-Tsung; Duh, Jenq-Gong

    2004-12-01

    The mechanical alloying (MA) process is considered an alternative approach to produce solder materials. In this study, the effect of Cu concentration in the ternary Sn-3.5Ag-xCu (x=0.2, 0.7, and 1) solder by MA was investigated. The (Cu,Sn) solid solution was precipitated as the Cu6Sn5 intermetallic compound (IMC), which was distributed nonuniformly through the microstructure. The Cu6Sn5 IMC, which was present in the SnAgCu solder with high Cu composition, causes the as-milled MA particle to fracture to a smaller size. Appreciable distinction on morphology of as-milled MA powders with different Cu content was revealed. When the Cu concentration was low (x=0.2), MA particle aggregated to a spherical ingot with large particle size. For higher Cu concentration (x=0.7 and x=1), the MA particle turned to flakes with smaller particle size. The distinction of the milling mechanism of Sn-3.5Ag-xCu (x=0.2, 0.7, and 1) solder by the MA process was discussed. An effective approach was developed to reduce the particle size of the SnAgCu solder from 1 mm down to 10-100 µm by doping the Cu6Sn5 nanoparticle during the MA process. In addition, the differential scanning calorimetry (DSC) results also ensure the compatibility to apply the solder material for the reflow process.

  3. Time-Dependent Damage Investigation of Rock Mass in an <em>In> em>Situ> Experimental Tunnel

    Directory of Open Access Journals (Sweden)

    Jing Chen

    2012-08-01

    Full Text Available In underground tunnels or caverns, time-dependent deformation or failure of rock mass, such as extending cracks, gradual rock falls, <em>etc>., are a costly irritant and a major safety concern if the time-dependent damage of surrounding rock is serious. To understand the damage evolution of rock mass in underground engineering, an <em>in situem> experimental testing was carried out in a large belowground tunnel with a scale of 28.5 m in width, 21 m in height and 352 m in length. The time-dependent damage of rock mass was detected in succession by an ultrasonic wave test after excavation. The testing results showed that the time-dependent damage of rock mass could last a long time, <em>i.e.>, nearly 30 days. Regression analysis of damage factors defined by wave velocity, resulted in the time-dependent evolutional damage equation of rock mass, which corresponded with logarithmic format. A damage viscoelastic-plastic model was developed to describe the exposed time-dependent deterioration of rock mass by field test, such as convergence of time-dependent damage, deterioration of elastic modules and logarithmic format of damage factor. Furthermore, the remedial measures for damaged surrounding rock were discussed based on the measured results and the conception of damage compensation, which provides new clues for underground engineering design.

  4. 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>.

  5. Electrical conductivity of Cu-Li alloys

    Institute of Scientific and Technical Information of China (English)

    朱达川; 宋明昭; 陈家钊; 涂铭旌; 潘海滨

    2004-01-01

    The electrical conductivity of Cu-Li alloys was studied. And the distribution of electrons near Fermi surface was detected by synchrotron radiation instrument. The results show that the electrical conductivity of Cu-Li alloys decreases from 5. 22 × 10-9 S/m to 3. 69 × 10-9 S/m with the increase of Li content. Li can decrease the oxygen, sulfur and other impurities content in commercial Cu, but Li dissolved in Cu lattice leads to distortion of Cu lattice from 0. 005 %-0. 050 %, affects the valence band of Cu, increases the binding energy of surface electron, and decreases the electron density of Fermi surface simultaneously. So the electrical conductivity decreases gradually with the increase of Li content.

  6. Manufacturing and High Heat Flux Testing of Brazed Flat-Type W/CuCrZr Plasma Facing Components

    Science.gov (United States)

    Lian, Youyun; Liu, Xiang; Feng, Fan; Chen, Lei; Cheng, Zhengkui; Wang, Jin; Chen, Jiming

    2016-02-01

    Water-cooled flat-type W/CuCrZr plasma facing components with an interlayer of oxygen-free copper (OFC) have been developed by using vacuum brazing route. The OFC layer for the accommodation of thermal stresses was cast onto the surface of W at a temperature range of 1150 °C-1200 °C in a vacuum furnace. The W/OFC cast tiles were vacuum brazed to a CuCrZr heat sink at 940 °C using the silver-free filler material CuMnSiCr. The microstructure, bonding strength, and high heat flux properties of the brazed W/CuCrZr joint samples were investigated. The W/Cu joint exhibits an average tensile strength of 134 MPa, which is about the same strength as pure annealed copper. High heat flux tests were performed in the electron beam facility EMS-60. Experimental results indicated that the brazed W/CuCrZr mock-up experienced screening tests of up to 15 MW/m2 and cyclic tests of 9 MW/m2 for 1000 cycles without visible damage. supported by National Natural Science Foundation of China (No. 11205049) and the National Magnetic Confinement Fusion Science Program of China (No. 2011GB110004)

  7. Iotron development of Cu67 radioisotope

    Energy Technology Data Exchange (ETDEWEB)

    Ehst, David A. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-10-31

    The collaboration has developed a method of producing the Cu-67 medical isotope for beta therapy of cancers such as non-Hodgkins melanoma. In particular we have used electron linac production of intense gamma ray beams to convert Zn-68 into Cu-67 in metal targets. The targets are subsequently processed by separating the Cu isotope from the Zn metal using sublimation, with ceramic components to avoid contamination of the final product.

  8. Purity of targets prepared on Cu substrates

    Science.gov (United States)

    Méens, A.; Rossini, I.; Sens, J. C.

    1993-09-01

    The purity of several elemental self-supporting targets usually prepared by evaporation onto soluble Cu substrates has been studied. The targets were analysed by Rutherford backscattering and instrumental neutron activation analysis. Because of the high percentage of Cu observed in some Si targets, further measurements, including transmission electron microscopy, have been performed on Si targets deposited by e-gun bombardment onto Cu and ion-beam sputtering onto betaine.

  9. Analyses of crack growth along interface of patterned wafer-level Cu-Cu bonds

    DEFF Research Database (Denmark)

    Tvergaard, Viggo; Hutchinson, John W.

    2009-01-01

    A preliminary theoretical study is carried out of the role of micron-scale patterning on the interface toughness of bonded Cu-to-Cu nanometer-scale films. The work is motivated by the experimental studies of [Tadepalli, R., Turner. K.T., Thompson, C.V., 2008b. Effects of patterning on the interface...... toughness of wafer-level Cu-Cu bonds. Acta Materialia 56, 438-447; Tadepalli, R., Turner, K.T., Thompson, C.V., 2008c. Mixed-mode interface toughness of wafer-level Cu-Cu bonds using asymmetric chevron test. J. Mech. Phys. Solids 56, 707-718.] wherein 400 nm Cu films were deposited in a variety of patterns...... on Si wafer substrates. Specimens were then produced by bringing the Cu surfaces into contact creating thermo-compression bonds. Interface toughness of these specimens was experimentally measured. The present study focuses on interface patterns comprised of bonded strips, called lines, alternating...

  10. 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.

  11. Efecto de extractos vegetales de <em>Polygonum hydropiperoidesem>, <em>Solanum nigrumem> y <em>Calliandra pittieriem> sobre el gusano cogollero (<em>Spodoptera frugiperdaem>

    Directory of Open Access Journals (Sweden)

    Lizarazo H. Karol

    2008-12-01

    Full Text Available

    El gusano cogollero <em>Spodoptera frugiperdaem> es una de las plagas que más afectan los cultivos en la región de Sumapaz (Cundinamarca, Colombia. En la actualidad se controla principalmente aplicando productos de síntesis química, sin embargo la aplicación de extractos vegetales surge como una alternativa de menor impacto sobre el ambiente. Este control se emplea debido a que las plantas contienen metabolitos secundarios que pueden inhibir el desarrollo de los insectos. Por tal motivo, la presente investigación evaluó el efecto insecticida y antialimentario de extractos vegetales de barbasco <em>Polygonum hydropiperoidesem> (Polygonaceae, carbonero <em>Calliandra pittieriem> (Mimosaceae y hierba mora <em>Solanum nigrumem> (Solanaceae sobre larvas de <em>S. frugiperdaem> biotipo maíz. Se estableció una cría masiva del insecto en el laboratorio utilizando una dieta natural con hojas de maíz. Posteriormente se obtuvieron extractos vegetales utilizando solventes de alta polaridad (agua y etanol y media polaridad (diclorometano los cuales se aplicaron sobre las larvas de segundo instar. Los resultados más destacados se presentaron con extractos de <em>P. hydropiperoidesem>, obtenidos con diclorometano en sus diferentes dosis, con los cuales se alcanzó una mortalidad de 100% 12 días después de la aplicación y un efecto antialimentario representado por un consumo de follaje de maíz inferior al 4%, efectos similares a los del testigo comercial (Clorpiriphos.

  12. Spatial part-set cuing facilitation.

    Science.gov (United States)

    Kelley, Matthew R; Parasiuk, Yuri; Salgado-Benz, Jennifer; Crocco, Megan

    2016-07-01

    Cole, Reysen, and Kelley [2013. Part-set cuing facilitation for spatial information. Journal of Experimental Psychology: Learning, Memory, & Cognition, 39, 1615-1620] reported robust part-set cuing facilitation for spatial information using snap circuits (a colour-coded electronics kit designed for children to create rudimentary circuit boards). In contrast, Drinkwater, Dagnall, and Parker [2006. Effects of part-set cuing on experienced and novice chess players' reconstruction of a typical chess midgame position. Perceptual and Motor Skills, 102(3), 645-653] and Watkins, Schwartz, and Lane [1984. Does part-set cuing test for memory organization? Evidence from reconstructions of chess positions. Canadian Journal of Psychology/Revue Canadienne de Psychologie, 38(3), 498-503] showed no influence of part-set cuing for spatial information when using chess boards. One key difference between the two procedures was that the snap circuit stimuli were explicitly connected to one another, whereas chess pieces were not. Two experiments examined the effects of connection type (connected vs. unconnected) and cue type (cued vs. uncued) on memory for spatial information. Using chess boards (Experiment 1) and snap circuits (Experiment 2), part-set cuing facilitation only occurred when the stimuli were explicitly connected; there was no influence of cuing with unconnected stimuli. These results are potentially consistent with the retrieval strategy disruption hypothesis, as well as the two- and three-mechanism accounts of part-set cuing.

  13. A NOTE ON THE LI-CU-O SYSTEM

    NARCIS (Netherlands)

    Berger, R

    1991-01-01

    In the Li-Cu-O system two new ternary phases have been found, tentatively described by the stoichiometries LiCu3O3 and LiCu2O2, and both containing Cu(I) and Cu(II). They exhibit p-type "hopping" conduction owing to localized charge carriers. Their powder patterns are successfully indexed on high-sy

  14. Delocalized mixed-valence bi- and trinuclear complexes with short Cu-Cu bonds.

    Science.gov (United States)

    Yang, Lei; Powell, Douglas R; Klein, Eric L; Grohmann, Andreas; Houser, Robert P

    2007-08-20

    Two mixed-valence copper complexes were synthesized with ligands N-(2-pyridylmethyl)acetamide (Hpmac) and N,N'-(2-methyl-2-pyridylpropan-1,3-diyl)bis(acetamide) (H2pp(ac)2). Dimer [Cu2(pmac)2]OTf and trimer [Cu3(pp(ac)2)2].NaOTf both contain fully delocalized, mixed-valence Cu(1.5)Cu(1.5) moieties.

  15. Synthesis, Characterization and Catalytic Activity of Cu/Cu2O Nanoparticles Prepared in Aqueous Medium

    Directory of Open Access Journals (Sweden)

    Sayed M. Badawy

    2015-07-01

    Full Text Available Copper/Copper oxide (Cu/Cu2O nanoparticles were synthesized by modified chemical reduction method in an aqueous medium using hydrazine as reducing agent and copper sulfate pentahydrate as precursor. The Cu/Cu2O nanoparticles were characterized by X-ray Diffraction (XRD, Energy Dispersive X-ray Fluorescence (EDXRF, Scanning Electron Microscope (SEM, and Transmission Electron Microscope (TEM. The analysis revealed the pattern of face-centered cubic (fcc crystal structure of copper Cu metal and cubic cuprites structure for Cu2O. The SEM result showed monodispersed and agglomerated particles with two micron sizes of about 180 nm and 800 nm, respectively. The TEM result showed few single crystal particles of face-centered cubic structures with average particle size about 11-14 nm. The catalytic activity of Cu/Cu2O nanoparticles for the decomposition of hydrogen peroxide was investigated and compared with manganese oxide MnO2. The results showed that the second-order equation provides the best correlation for the catalytic decomposition of H2O2 on Cu/Cu2O. The catalytic activity of hydrogen peroxide by Cu/Cu2O is less than the catalytic activity of MnO2 due to the presence of copper metal Cu with cuprous oxide Cu2O. © 2015 BCREC UNDIP. All rights reservedReceived: 6th January 2015; Revised: 14th March 2015; Accepted: 15th March 2015How to Cite: Badawy, S.M., El-Khashab, R.A., Nayl, A.A. (2015. Synthesis, Characterization and Catalytic Activity of Cu/Cu2O Nanoparticles Prepared in Aqueous Medium. Bulletin of Chemical Reaction Engineering & Catalysis, 10 (2: 169-174. (doi:10.9767/bcrec.10.2.7984.169-174 Permalink/DOI: http://dx.doi.org/10.9767/bcrec.10.2.7984.169-174  

  16. Measurement of thermal contact resistance at Cu-Cu interface

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Myung Su; Choi, Yeon Suk [Korea Basic Science Institute, Daejeon,(Korea, Republic of)

    2013-06-15

    The thermal contact resistance (TCR) is one of the important components in the cryogenic systems. Especially, cryogenic measurement devices using a cryocooler can be affected by TCR because the systems have to consist of several metal components in contact with each other for heat transferring to the specimen without cryogen. Therefore, accurate measurement and understanding of TCR is necessary for the design of cryogenic measurement device using a cryocooler. The TCR occurs at the interface between metals and it can be affected by variable factors, such as roughness of metal surface, contact area and contact pressure. In this study, we designed TCR measurement system at various temperatures using a cryocooler as a heat sink and used steady state method to measure the TCR between metals. The copper is selected as a specimen in the experiment because it is widely used as a heat transfer medium in the cryogenic measurement devices. The TCR between Cu and Cu is measured for various temperatures and contact pressures. The effect of the interfacial materials on the TCR is also investigated.

  17. 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

  18. Alloying effect via comparative studies of ethanol dehydrogenation on Cu(1 1 1), Cu3Pd(1 1 1), and Cu3Pt(1 1 1)

    Science.gov (United States)

    Wu, Ruitao; Wang, Lichang

    2017-06-01

    Ethanol dehydrogenations on Cu(1 1 1), Cu3Pd(1 1 1), and Cu3Pt(1 1 1) were studied using density functional theory with a PBE functional. The α-C-H and β-C-H scissions are endothermic on all surfaces while the O-H scission is exothermic on Cu(1 1 1) and Cu3Pt(1 1 1) but endothermic on Cu3Pd(1 1 1). The ethanol dehydrogenation occurs on Cu(1 1 1) through both α-C-H and O-H scissions but on Cu3Pd(1 1 1) and Cu3Pt(1 1 1) through only α-C-H scission. Furthermore, alloying Pt or Pd with Cu shows an increase in reaction rate at 493 K by more than 3 orders of magnitude, thus illustrating the promise of alloying Pt or Pd in Cu catalysts for ethanol dehydrogenation.

  19. Toxicity of CuO nanoparticles and Cu ions to tight epithelial cells from Xenopus laevis (A6)

    DEFF Research Database (Denmark)

    Thit, Amalie; Selck, Henriette; Bjerregaard, Henning F.

    2013-01-01

    ) was used to investigate toxicity of copper (Cu) in 3 different forms; Cu ions (Cu2+), CuO NPs (6 nm) and poly-dispersed CuO NPs (100 nm, poly-CuO). Continuous exposures at concentrations of 143–200 μM demonstrated that cytotoxicity differed among the 3 Cu forms tested and that the effects depend on cell...... state (dividing or differentiated). Dividing cells treated with poly-CuO, CuO NPs (6 nm) or Cu2+ showed cell cycle arrest and caused significant increase in cell death via apoptosis after 48 h, 6 and 7 days of treatment, respectively. Treatment with either CuO NPs (6 nm) or Cu2+ caused significant...... decrease in cell proliferation. Treatments of differentiated cells, revealed the same patterns of toxicity for Cu forms tested, but after shorter exposure periods....

  20. Genetic Diversity of <em>Pinus nigraem> Arn. Populations in Southern Spain and Northern Morocco Revealed By Inter-Simple Sequence Repeat Profiles

    Directory of Open Access Journals (Sweden)

    Oussama Ahrazem

    2012-05-01

    Full Text Available Eight <em>Pinus nigraem> Arn. populations from Southern Spain and Northern Morocco were examined using inter-simple sequence repeat markers to characterize the genetic variability amongst populations. Pair-wise population genetic distance ranged from 0.031 to 0.283, with a mean of 0.150 between populations. The highest inter-population average distance was between PaCU from Cuenca and YeCA from Cazorla, while the lowest distance was between TaMO from Morocco and MA Sierra Mágina populations. Analysis of molecular variance (AMOVA and Nei’s genetic diversity analyses revealed higher genetic variation within the same population than among different populations. Genetic differentiation (<em>Gst> was 0.233. Cuenca showed the highest Nei’s genetic diversity followed by the Moroccan region, Sierra Mágina, and Cazorla region. However, clustering of populations was not in accordance with their geographical locations. Principal component analysis showed the presence of two major groups—Group 1 contained all populations from Cuenca while Group 2 contained populations from Cazorla, Sierra Mágina and Morocco—while Bayesian analysis revealed the presence of three clusters. The low genetic diversity observed in PaCU and YeCA is probably a consequence of inappropriate management since no estimation of genetic variability was performed before the silvicultural treatments. Data indicates that the inter-simple sequence repeat (ISSR method is sufficiently informative and powerful to assess genetic variability among populations of <em>P. nigraem>.

  1. <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.

  2. Facetas em dentes anteriores

    OpenAIRE

    Veloso, Helena Rafaela Lourenço Martins

    2015-01-01

    Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Medicina Dentária A presente revisão bibliográfica aborda as facetas estéticas em dentes anteriores, pela crescente valorização de um sorriso esteticamente agradável, facto que faz com que as pessoas procurem cada vez mais alternativas de tratamento para melhorar a aparência do seu sorriso. Os dentes anteriores são decisivos na aparência estética e, c...

  3. Response of the Cu(II) ion selective electrode to Cu titration in artificial and natural shore seawater and in the measurement of the Cu complexation capacity.

    Science.gov (United States)

    Rivera-Duarte, Ignacio; Zirino, Alberto

    2004-06-01

    The Orion 94-29 Cu(II) jalpaite ion selective electrode (Cu-ISE) was used to measure both the concentration of the aqueous free Cu(II) ion ([Cu(II)aq]) and its changes due to additions of Cu, in artificial seawater (ASW) and in seawater from San Diego Bay, CA. The range of free copper ion (i.e., pCu, -log [Cu(II)aq]) determined in seawater samples from the San Diego Bay area (11.3-12.6, 11.9 +/- 0.4, average +/- SD) is consistent with that previously reported for estuarine and coastal areas (10.9-14.1). The changes in [Cu(II)aq] as a result of the additions of Cu were used to determine the Cu complexation capacity (Cu-CC), which has a measured range (2.7 x 10(-8)-2.0 x 10(-7) M; 7.6 x 10(-8) +/- 4.8 x 10(-8) M) comparable to the range of values previously reported for estuarine and coastal zones (i.e., L1+L2, 1.1 x 10(-8)-2.0 x 10(-7) M). The narrow range of pCu at the Cu-CC (pCuCu-CC, 11.1-11.9, 11.5 +/- 0.2) indicates the predominant role of the Cu-CC in regulating the concentration of ambient Cu(II)aq to a level < or =1 x 10(-11) M Cu(II)aq. These results attest to the capability of the Cu-ISE to measure pCu and Cu-CC in aquatic coastal environments with relatively high total Cu concentrations and organic loads, such as those from heavily used coasts and bays.

  4. EMS & the DEA.

    Science.gov (United States)

    Beeson, Jeff; Ayres, Chris

    2010-01-01

    It's clear that EMS medical directors and management staff must be vigilant in their oversight of implementation, administration and monitoring of controlled substances within their agencies to best serve the public and avoid running afoul of investigation and incurring significant penalties. Those potentially affected by the need for individual registrations of both emergency vehicles and central inventory systems should carefully monitor upcoming developments in the interpretation od DEA regulations.

  5. CORANTES ARTIFICIAIS EM ALIMENTOS

    Directory of Open Access Journals (Sweden)

    Marcelo Alexandre PRADO

    2009-07-01

    Full Text Available

    O emprego de aditivos químicos é, sem dúvida, um dos mais polêmicos avanços alcançados pela indústria de alimentos. Os corantes artificiais pertencem a uma dessas classes de aditivos alimentares e têm sido objeto de muitas críticas, já que seu uso em muitos alimentos justifica-se apenas por questões de hábitos alimentares. Ainda existem diferentes opiniões quanto à inocuidade dos diversos corantes artificiais. Visando, principalmente, o controle no uso dos corantes sintéticos, mas tendo em vista que produtos coloridos artificialmente são exportados e importados, a análise desses aditivos requer métodos eficientes e rápidos para a detecção, identificação e quantificação. A cromatografia em papel e em camada delgada, apesar de serem técnicas relativamente rápidas, apresentam dados com baixa exatidão e precisão. Já na cromatografia líquida de alta eficiência (CLAE as maiores dificuldades encontram-se nas etapas de extração, mas principalmente no alto custo do equipamento. A eletroforese capilar apresenta os mesmos problemas da CLAE, aliados ao fato de se tratar de uma técnica relativamente recente para a análise desse tipo de substância e, portanto, existem poucos estudos a cerca da determinação e quantificação. PALAVRAS-CHAVE: Corantes artificiais; análise; legislação; CLAE; EC

  6. Bacharelado em Psicopedagogia

    OpenAIRE

    Ramos, Maria Beatriz Jacques; PUCRS

    2007-01-01

    Este texto mostra a história da implantação do Curso de Bacharelado em Psicopedagogia na FACED, PUCRS. Neste texto são apresentados os referenciais teóricos e dados sobre a atuação do psicopedagogo nos campos preventivo e terapêutico explicitando a relevância da formação de profissionais nesta área. Descritores – Psicopedagogia; aprendizagem; problema de aprendizagem.

  7. The Cubesat mission to study Solar Particles (CuSP), an interplanetary cubesat

    Science.gov (United States)

    Christian, E. R.; Desai, M. I.; Allegrini, F.; Jahn, J. M.; Kanekal, S.; Livi, S. A.; Murphy, N.; Ogasawara, K.; Paschalidis, N.

    2015-12-01

    The Cubesat mission to study Solar Particles (CuSP) is a funded 6U interplanetary cubesat scheduled to fly on the EM-1 SLS launch in 2018. CuSP has three small but capable instruments from the Southwest Research Institute (SwRI), NASA Goddard Space Flight Center (GSFC), and the NASA Jet Propulsion Laboratory (JPL). Its primary scientific goal is high-cadence precise measurements of the suprathermal (ST) tail in the solar wind. The suprathermal tail is the critical bridge between the thermal solar wind plasma and the dangerous high-energy solar energetic particles. CuSP also measures the energy spectra and composition of the ~1-50 MeV/nucleon H-Fe ions that evolve from the STs and the interplanetary magnetic field that is closely coupled to the particle distributions. CuSP is a stepping-stone to future interplanetary cubesats, smallsats, and constellations for both scientific and space weather applications. The challenges for this mission and future missions will also be discussed.

  8. Behavior of Brazed W/Cu Mockup Under High Heat Flux Loads

    Science.gov (United States)

    Chen, Lei; Lian, Youyun; Liu, Xiang

    2014-03-01

    In order to transfer the heat from the armor to the coolant, tungsten has to be connected with a copper heat sink. The joint technology is the most critical issue for manufacturing plasma facing components. Consequently, the reliability of the joints should be verified by a great number of high-heat-flux (HHF) tests to simulate the real load conditions. W/Cu brazed joint technology with sliver free filler metal CuMnNi has been developed at Southwestern Institute of Physics (SWIP). Screening and thermal fatigue tests of one small-scale flat tile W/CuCrZr mockup were performed on a 60 kW electron-beam Material testing scenario (EMS-60) constructed recently at SWIP. The module successfully survived screening test with the absorbed power density (Pabs) of 2 MW/m2 to 10 MW/m2 and the following 1000 cycles at Pabs of 7.2 MW/m2 without hot spots and overheating zones during the whole test campaign. Metallurgy and SEM observations did not find any cracks at both sides and the interface, indicating a good bonding of W and CuCrZr alloy. In addition, finite element simulations by ANSYS 12.0 under experimental load conditions were performed and compared with experimental results.

  9. 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.

  10. 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>.

  11. Quedas em doentes hospitalizados: contributos para uma prática baseada na prevenção Caídas en pacientes hospitalizados: contribución para una práctica basada en la prevención Falls in hospitalized patients: contributions to practice based on prevention

    Directory of Open Access Journals (Sweden)

    Ricardo Alexandre Rebelo de Almeida

    2010-12-01

    Full Text Available As quedas surgem como os acidentes mais documentados no hospital, assumindo particular destaque pelas consequências individuais que originam e pelo aumento do tempo de internamento, ampliando custos económicos e sociais. O objectivo deste artigo é contribuir para uma maior compreensão do fenómeno da queda, sensibilizando os enfermeiros para o seu estudo e incorporação nas práticas de cuidados, através da análise e caracterização do fenómeno da queda, procurando na literatura científica contributos para a sua melhor compreensão e desenvolvimento de estratégias de actuação/prevenção. Foi realizada uma revisão da literatura, com pesquisa em bases de dados (B-on e EBSCO-host e no acervo bibliográfico da Escola Superior de Enfermagem de Coimbra. Na literatura científica a queda surge como evento multifactorial de causas individuais ou ambientais. Embora a investigação desenvolvida nesta área destaque alguns factores de risco, estes são eminentemente contextuais e relacionados com características específicas das pessoas. Assim, a avaliação do risco individual, a determinação de factores de risco e a constituição de protocolos de intervenção, surgem como medidas eficazes de prevenção. Os enfermeiros são profissionais de eleição na promoção da segurança do utente, desenvolvendo/utilizando instrumentos de avaliação do risco e implementando medidas de prevenção, baseadas na evidência científica e suportados em formação continuada.Las caídas aparecen como los accidentes más documentados en el hospital, asumiendo particular destaque por las consecuencias individuales que originan y por el aumento del tiempo de internamiento, ampliando costos económicos y sociales. El objetivo de este artículo es contribuir para una mayor comprensión del fenómeno de caída, sensibilizando a los enfermeros de su estudio e incorporación en las prácticas de cuidados, a través del análisis y caracterización del fen

  12. Interfacial Reaction of Sn-Ag-Cu Lead-Free Solder Alloy on Cu: A Review

    OpenAIRE

    Liu Mei Lee; Ahmad Azmin Mohamad

    2013-01-01

    This paper reviews the function and importance of Sn-Ag-Cu solder alloys in electronics industry and the interfacial reaction of Sn-Ag-Cu/Cu solder joint at various solder forms and solder reflow conditions. The Sn-Ag-Cu solder alloys are examined in bulk and in thin film. It then examines the effect of soldering conditions to the formation of intermetallic compounds such as Cu substrate selection, structural phases, morphology evolution, the growth kinetics, temperature and time is also disc...

  13. Bubbfil electrospinning of PA66/Cu nanofibers

    Directory of Open Access Journals (Sweden)

    Li Ya

    2016-01-01

    Full Text Available Different PA66/Cu nanofibers were prepared under various electrospinning parameters through bubbfil electrospinning. The process parameters were determined. Cuprum particles with different size were added to PA66 solution to produce PA6/66-Cu composite nanofibers. The influence of cuprum nanoparticle size on the PA66 nanofibers was analyzed.

  14. Interfacial Phenomena in Al/Al, Al/Cu, and Cu/Cu Joints Soldered Using an Al-Zn Alloy with Ag or Cu Additions

    Science.gov (United States)

    Pstruś, Janusz; Gancarz, Tomasz

    2014-05-01

    The studies of soldered joints were carried out in systems: Al/solder/Al, Al/solder/Cu, Cu/solder/Cu, where the solder was (Al-Zn)EUT, (Al-Zn)EUT with 0.5, 1.0, and 1.5 at.% of Ag and (Al-Zn)EUT with 0.5, 1.0, and 1.5 at.% of Cu addition. Brazing was performed at 500 °C for 3 min. The EDS analysis indicated that the composition of the layers starting from the Cu pad was CuZn, Cu5Zn8, and CuZn4, respectively. Wetting tests were performed at 500 °C for 3, 8, 15, and 30 min, respectively. Thickness of the layers and their kinetics of growth were measured based on the SEM micrographs. The formation of interlayers was not observed from the side of Al pads. On the contrary, dissolution of the Al substrate and migration of Al-rich particles into the bulk of the solder were observed.

  15. Indium-free, highly transparent, flexible Cu2O/Cu/Cu2O mesh electrodes for flexible touch screen panels

    Science.gov (United States)

    Kim, Dong-Ju; Kim, Hyo-Joong; Seo, Ki-Won; Kim, Ki-Hyun; Kim, Tae-Wong; Kim, Han-Ki

    2015-11-01

    We report on an indium-free and cost-effective Cu2O/Cu/Cu2O multilayer mesh electrode grown by room temperature roll-to-roll sputtering as a viable alternative to ITO electrodes for the cost-effective production of large-area flexible touch screen panels (TSPs). By using a low resistivity metallic Cu interlayer and a patterned mesh structure, we obtained Cu2O/Cu/Cu2O multilayer mesh electrodes with a low sheet resistance of 15.1 Ohm/square and high optical transmittance of 89% as well as good mechanical flexibility. Outer/inner bending test results showed that the Cu2O/Cu/Cu2O mesh electrode had a mechanical flexibility superior to that of conventional ITO films. Using the diamond-patterned Cu2O/Cu/Cu2O multilayer mesh electrodes, we successfully demonstrated TSPS of the flexible film-film type and rigid glass-film-film type TSPs. The TSPs with Cu2O/Cu/Cu2O mesh electrode were used to perform zoom in/out functions and multi-touch writing, indicating that these electrodes are promising cost-efficient transparent electrodes to substitute for conventional ITO electrodes in large-area flexible TSPs.

  16. Indium-free, highly transparent, flexible Cu2O/Cu/Cu2O mesh electrodes for flexible touch screen panels

    National Research Council Canada - National Science Library

    Kim, Dong-Ju; Kim, Hyo-Joong; Seo, Ki-Won; Kim, Ki-Hyun; Kim, Tae-Wong; Kim, Han-Ki

    2015-01-01

    ... production of large-area flexible touch screen panels (TSPs). By using a low resistivity metallic Cu interlayer and a patterned mesh structure, we obtained Cu2O/Cu/Cu2O multilayer mesh electrodes with a low sheet resistance of 15.1...

  17. DISTRIBUTION OF CU AND ITS EFFECT ON MICROSTRUCTURE OF CU-BEARING STEEL

    Institute of Scientific and Technical Information of China (English)

    CHEN Xinhua; DONG Junhua; HAN Enhou; KE Wei

    2006-01-01

    In order to investigate the distribution of Cu and its effect on the microstructure of Cu-bearing steel, a series of mild steels containing different contents of Cu are developed by vacuum electric arc furnace. These steels are annealed at 1 260 ℃, 1 100 ℃ and 1 000 ℃ respectively for one hour and followed by furnace cooling to room temperature to simulate the heat treatment before the rolling process. The results show that Cu did not obviously segregate in annealed steels. The scanning electron microscope (SEM) observation show that the main microstructures in Cu-bearing steel are ferrite and pearlite; The volume fraction of pearlite in steel increase with increasing Cu content. The grain size reduces with the decrease of annealing temperature. The results of energy dispersive X-ray analysis (EDXA) suggest that the Cu content in pearlite is higher than that in ferrite, which means that the microstructure-segregation of Cu exists. However, the cast specimens show that Cu content in MnS and S-rich phase is very high, and Cu changed the distribution of MnS in steel. In addition, the optimal Cu content in steel between 0.2%~0.4% and the optimal annealing temperature between 1100~1 200 ℃ are determined by the economical and practical principles.

  18. Electrochemical behavior of Cu in the (NaCl-KCl-CuCl)molten salt

    Institute of Scientific and Technical Information of China (English)

    Yungang LI; Jie LI; Kuai ZHANG; Limin LIU

    2011-01-01

    The electrochemical reaction mechanism and electrocrystallization process of Cu on copper electrode in the eutectic NaC1-KC1-CuC1 molten salt were investigated by means of cyclic voltammetry,chronopotentiometry and chronoamperometry technique at 710 ℃.The results show that the electrochemical reaction process of Cu is a quasi-reversible process mix-controlled by Cu+ diffusion rate and electron transport rate; the electrochemical reduction mechanism is Cu++e→Cu; the electrocrystallization process of copper is an instantaneous hemispheroid three-dimensional nucleation process; the Cu+ diffusion coefficient is 4.3×10-4 cm2·s-1 under the experimental conditions.

  19. High volumetric uptake of ammonia using Cu-MOF-74/Cu-CPO-27.

    Science.gov (United States)

    Katz, Michael J; Howarth, Ashlee J; Moghadam, Peyman Z; DeCoste, Jared B; Snurr, Randall Q; Hupp, Joseph T; Farha, Omar K

    2016-03-14

    Cu-MOF-74 (also known as Cu-CPO-27) was identified as a sorbent having one of the highest densities of Cu(ii) sites per unit volume. Given that Cu(ii) in the framework can be thermally activated to yield a five-coordinate Cu(ii) species, we identified this MOF as a potential candidate for maximal volumetric uptake of ammonia. To that end, the kinetic breakthrough of ammonia in Cu-MOF-74/Cu-CPO-27 was examined under both dry and humid conditions. Under dry conditions the MOF exhibited a respectable performance (2.6 vs. 2.9 NH3 per nm(3) for the current record holder HKUST-1), and under 80% relative humidity, the MOF outperformed HKUST-1 (5.9 vs. 3.9 NH3 per nm(3), respectively).

  20. Interfacial Reaction of Sn-Ag-Cu Lead-Free Solder Alloy on Cu: A Review

    Directory of Open Access Journals (Sweden)

    Liu Mei Lee

    2013-01-01

    Full Text Available This paper reviews the function and importance of Sn-Ag-Cu solder alloys in electronics industry and the interfacial reaction of Sn-Ag-Cu/Cu solder joint at various solder forms and solder reflow conditions. The Sn-Ag-Cu solder alloys are examined in bulk and in thin film. It then examines the effect of soldering conditions to the formation of intermetallic compounds such as Cu substrate selection, structural phases, morphology evolution, the growth kinetics, temperature and time is also discussed. Sn-Ag-Cu lead-free solder alloys are the most promising candidate for the replacement of Sn-Pb solders in modern microelectronic technology. Sn-Ag-Cu solders could possibly be considered and adapted in miniaturization technologies. Therefore, this paper should be of great interest to a large selection of electronics interconnect materials, reliability, processes, and assembly community.

  1. Lattice location of implanted Cu in Si

    CERN Document Server

    Wahl, U; Vantomme, A; Langouche, G

    1999-01-01

    We have implanted the radioactive probe atom $^{67}$Cu ($t_{1/2}$=61.9 h) into single-crystalline Si. Monitoring the $\\beta^{-}$-emission yield from the decay of $^{67}$Cu to $^{67}$Zn as a function of angle from different crystallographic directions allows to determine the lattice location of the Cu atoms by means of the emission channeling effect. We give direct evidence that the majority of implanted Cu occupies near-substitutional sites. As most-likely lattice location we suggest a displacement of 0.51(7) along directions from substitutional sites to bond center positions. The annealing behavior shows that near-substitutional Cu is remarkably stable, and we estimate a dissociation energy of 2.2(3) eV.

  2. Phase equilibrium in Mg-Cu-Y

    Science.gov (United States)

    Mezbahul-Islam, Mohammad; Medraj, Mamoun

    2013-10-01

    Magnesium-based bulk metallic glasses (BMG) have potential in applications ranging from biomedical to sports equipment and the Mg-Cu-Y system offers some of the most promising alloys. Phase relations and ternary solubility of the binary and ternary compounds of this system have been experimentally investigated. The Isothermal section of Mg-Cu-Y system at 673 K for the entire composition range has been constructed. Phase relations in the Cu-rich (>66 at.% Cu) region of the Mg-Cu-Y system has been determined for the first time. The homogeneity range of three ternary compounds has been determined. Solidifications behavior of several key alloys have been discussed based on the differential scanning calorimetry (DSC) experiments and thermodynamic calculations. Extensive analysis of the DSC curves has been carried out to relate them to the corresponding phase transformation reactions and temperatures. Some of the most promising metallic glass forming regions have been analyzed using thermodynamic calculations.

  3. 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.

  4. Indium-free, highly transparent, flexible Cu2O/Cu/Cu2O mesh electrodes for flexible touch screen panels

    OpenAIRE

    Dong-Ju Kim; Hyo-Joong Kim; Ki-Won Seo; Ki-Hyun Kim; Tae-Wong Kim; Han-Ki Kim

    2015-01-01

    We report on an indium-free and cost-effective Cu2O/Cu/Cu2O multilayer mesh electrode grown by room temperature roll-to-roll sputtering as a viable alternative to ITO electrodes for the cost-effective production of large-area flexible touch screen panels (TSPs). By using a low resistivity metallic Cu interlayer and a patterned mesh structure, we obtained Cu2O/Cu/Cu2O multilayer mesh electrodes with a low sheet resistance of 15.1?Ohm/square and high optical transmittance of 89% as well as good...

  5. Isolation and Characterization of Microsatellite Markers in Brown Planthopper (<em>Nilaparvata em>lugens> Stål

    Directory of Open Access Journals (Sweden)

    Guangcun He

    2012-07-01

    Full Text Available Brown planthopper (<em>Nilaparvata lugensem> Stål (Homoptera: Delphacidae is an economically important pest on rice. In this study, 30 polymorphic microsatellite markers were developed from <em>N. lugensem> genomic libraries using the method of Fast Isolation by AFLP of Sequence Containing Repeats (FIASCO. Polymorphism of each locus was detected in 48 individuals from two natural populations. These microsatellite loci revealed 2 to 18 alleles, and the expected and observed heterozygosities ranged from 0.042 to 0.937 and from 0.042 to 0.958, respectively. These markers will be useful for the future study of this agricultural pest in population genetics and molecular genetics.

  6. Reactions in Electrodeposited Cu/Sn and Cu/Ni/Sn Nanoscale Multilayers for Interconnects

    Directory of Open Access Journals (Sweden)

    Pay Ying Chia

    2016-05-01

    Full Text Available Miniaturization of electronic devices has led to the development of 3D IC packages which require ultra-small-scale interconnections. Such small interconnects can be completely converted into Cu-Sn based intermetallic compounds (IMCs after reflow. In an effort to improve IMC based interconnects, an attempt is made to add Ni to Cu-Sn-based IMCs. Multilayer interconnects consisting of stacks of Cu/Sn/Cu/Sn/Cu or Cu/Ni/Sn/Ni/Sn/Cu/Ni/Sn/Ni/Cu with Ni = 35 nm, 70 nm, and 150 nm were electrodeposited sequentially using copper pyrophosphate, tin methanesulfonic, and nickel Watts baths, respectively. These multilayer interconnects were investigated under room temperature aging conditions and for solid-liquid reactions, where the samples were subjected to 250 °C reflow for 60 s and also 300 °C for 3600 s. The progress of the reaction in the multilayers was monitored by using X-ray Diffraction, Scanning Electron Microscope, and Energy dispersive X-ray Spectroscopy. FIB-milled samples were also prepared for investigation under room temperature aging conditions. Results show that by inserting a 70 nanometres thick Ni layer between copper and tin, premature reaction between Cu and Sn at room temperature can be avoided. During short reflow, the addition of Ni suppresses formation of Cu3Sn IMC. With increasing Ni thickness, Cu consumption is decreased and Ni starts acting as a barrier layer. On the other hand, during long reflow, two types of IMC were found in the Cu/Ni/Sn samples which are the (Cu,Ni6Sn5 and (Cu,Ni3Sn, respectively. Details of the reaction sequence and mechanisms are discussed.

  7. Negative-Pressure Cavitation Extraction of Four Main Vinca Alkaloids from <em>Catharanthus em>roseus> Leaves

    OpenAIRE

    Yuangang Zu; Xiaorui Guo; Yujie Fu; Meng Luo; Wei Wang; Liuqing Yang; Fansong Mu

    2012-01-01

    In the present study, an improved method termed negative-pressure cavitation extraction (NPCE) followed by reverse phase high-performance liquid chromatography (RP-HPLC) was developed for the extraction and quantification of vindoline (VDL), catharanthine (CTR), vincristine (VCR) and vinblastine (VLB) from <em>Catharanthus roseus em>leaves. The optimized method employed 60-mesh particles, 80% ethanol, a negative pressure of −0.075 MPa, a solid to liquid ratio of 1:20, 30 min of ...

  8. 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.

  9. Movimentação de metais pesados em Latossolo adubado com composto de lixo urbano

    Directory of Open Access Journals (Sweden)

    Oliveira Fernando Carvalho

    2002-01-01

    Full Text Available Em experimento realizado no campo, nos anos agrícolas 1996/97 e 1997/98, em Latossolo Amarelo distrófico, cultivado com cana-de-açúcar, avaliou-se o efeito de aplicações sucessivas de composto de lixo urbano sobre a movimentação, em profundidade, dos metais Cd, Cr, Cu, Ni, Pb e zinco. No primeiro ano agrícola, além do tratamento testemunha, o composto de lixo foi aplicado nas doses de 20, 40 e 60 Mg ha-1 (base seca. No segundo ano, o composto foi reaplicado nas doses de 24, 48 e 72 Mg ha-1. Em relação aos metais Cd, Cr, Cu, Ni e Pb não se observou nenhuma evidência de movimentação ao longo do perfil do solo. O Zn apresentou mobilidade no solo, onde se verificou, ao final de 1997/98, incrementos significativos até a camada de 0,4-0,6 m de profundidade.

  10. 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.

  11. 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.

  12. An unusual coordination polymer containing Cu(+) ions and featuring possible Cu...Cu `cuprophilic' interactions: poly[di-μ-chlorido-(μ4-3,5-diaminobenzoato-κ(4)O:O':N:N')tricopper(I)(3 Cu-Cu)].

    Science.gov (United States)

    Khosa, Muhammad Kaleem; Wood, Paul T; Humphrey, Simon M; Harrison, William T A

    2016-01-01

    Compounds containing copper(I) are of interest for their role in biological processes. The nature of short (coordination polymer, [Cu3(C7H7N2O2)Cl2]n, was formed from the in situ reduction of CuCl2 in the presence of 3,5-diaminobenzoic acid and KOH under hydrothermal conditions. Its complex crystal structure contains ten distinct Cu(I) atoms, two of which lie on crystallographic inversion centres. The copper coordination geometries include near-linear CuOCl and CuN2, T-shaped CuOCl2 and distorted tetrahedral CuOCl3 groups. Each Cu(I) atom is also associated with two adjacent metal atoms, with Cu...Cu distances varying from 2.7350 (14) to 3.2142 (13) Å; if all these are regarded as `cuprophilic' interactions, then infinite [-101] zigzag chains of Cu(I) atoms occur in the crystal. The structure is consolidated by N-H...Cl hydrogen bonds.

  13. Fungos micorrízicos no crescimento e na extração de metais pesados pela braquiária em solo contaminado Mycorrhizal fungi influence on brachiariagrass growth and heavy metal extraction in a contaminated soil

    Directory of Open Access Journals (Sweden)

    Silvana da Silva

    2006-12-01

    Full Text Available Avaliou-se, em casa de vegetação, a influência de 14 isolados de fungos micorrízicos arbusculares (FMA no crescimento e extração de Zn, Cd, Cu e Pb pela Brachiaria decumbens em solo contaminado. Foram utilizadas plantas com e sem FMA, em vasos com 0,92 kg de solo com (mg kg-1: Zn, 3.300; Cu, 60; Cd, 29; Pb, 73. Os isolados fúngicos tiveram efeitos diferenciados no crescimento e aumentaram a produção de matéria seca em 84%. Os teores de metais na planta foram elevados e apresentaram relação inversa com a produção de matéria seca. Verificou-se que os FMA não afetaram os teores de Pb, mas reduziram em 20, 28 e 63% os teores de Zn, Cd e Cu na parte aérea, respectivamente, e aumentaram os teores de Cu nas raízes em mais de 1.000%. Os FMA aumentaram a quantidade de metais extraídos do solo em 845, 142, 68 e 54% para Cu, Pb, Zn e Cd, respectivamente. Acaulospora spinosa, Acaulospora morrowiae-UFLA e Gigaspora gigantea aumentaram a extração simultânea dos quatro metais contaminantes. Os FMA, de acordo com a espécie, aumentam a capacidade da B. decumbens de extrair metais pesados do solo.The influence of 14 arbuscular mycorrhiza fungal isolates (AMF on brachiariagrass growth and extraction of Zn, Cd, Cu and Pb from a contaminated soil was evaluated in a greenhouse experiment. Mycorrhizal and nonmycorrhizal Brachiaria decumbens plants were grown in pots with 0.92 kg of soil containing (mg kg-1: Zn, 3,300; Cu, 60; Cd, 29; Pb, 73. The AMF increased dry matter yield in 84%. Plant heavy metal concentrations were high and were inversely related to dry matter yield. Isolates caused no effect on Pb, but reduced shoot Zn, Cd and Cu concentrations by 20, 28 and 63%, respectively. It was observed effect of mycorrhiza on Cu accumulation in roots (over 1,000%. Isolates enhanced the total amount of soil extracted metals by 845, 142, 68 and 54% for Cu, Pb, Zn and Cd, respectively. Only Acaulospora spinosa, Acaulospora morrowiae-UFLA and Gigaspora

  14. Sintomas visuais de deficiências nutricionais em pinhão-manso.

    OpenAIRE

    2009-01-01

    O objetivo deste trabalho foi avaliar o crescimento e caracterizar os sintomas de deficiências de macro e micronutrientes em mudas de pinhão-manso (Jatropha curcas). As mudas foram cultivadas em solução nutritiva completa e, também, em soluções com omissão de N, P, K, Ca, Mg, S, B, Cu, Fe, Mn ou Zn, pelo uso da técnica do elemento faltante. Foram avaliados os sintomas visuais de deficiência de nutrientes e a massa de matéria seca da parte aérea e das raízes, respectivamente aos 90 e 120 dias ...

  15. Identification and Characterization of a <em>Bursaphelenchus xylophilusem> (Aphelenchida: Aphelenchoididae Thermotolerance-Related Gene: <em>Bx-HSP90em>

    Directory of Open Access Journals (Sweden)

    Danlei Li

    2012-07-01

    Full Text Available Temperatures directly influence the distribution and intensity of pine wilt disease caused by the pine wood nematode, <em>Bursaphelenchus xylophilusem>. To date, however, little is known about the causation and mechanism of this influence. The molecular chaperone HSP90 is a key component that contributes to survival in the abiotic stress response. In this study, we investigated the relationship between the survival of <em>B. xylophilusem> and the functionality of the HSP90 gene<em>.> <em>Bx-HSP90 em>was cloned from a suppression subtractive hybridization library. <em>In situem> mRNA hybridization showed that <em>Bx-HSP90em> was constitutively expressed in response to all of the temperatures tested, and RT-PCR indicated that all of the temperatures could induce <em>Bx-HSP90 em>transcription, with the highest transcript level detected at 30 °C. The suppression of the <em>Bx-HSP90em> transcript by RNA interference led to a 25% reduction in the number of nematodes at 30 °C after 44 h. Sharp declines in the survival of the RNAi-treated nematodes were observed after 8 days at 25 °C, 48 h at 30 °C and 24 h at 35 °C. Both heat shock and the knockdown of <em>Bx-HSP90 em>hindered the growth of the <em>B. xylophilusem> populations. The results indicate that <em>Bx-HSP90em> is essential for the survival of <em>B. xylophilusem>, confirming the thermoregulatory function of the gene, and delineate the timeframe and temperature range within which the gene function occurs.

  16. 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>.

  17. Atom probe study of Cu-poor to Cu-rich transition during Cu(In,Ga)Se2 growth

    Science.gov (United States)

    Couzinie-Devy, F.; Cadel, E.; Barreau, N.; Arzel, L.; Pareige, P.

    2011-12-01

    Atomic scale chemistry of polycrystalline Cu(In,Ga)Se2 (CIGSe) thin film has been characterized at key points of the 3-stage process using atom probe tomography. 3D atom distributions have been reconstructed when the layer is Cu-poor ([Cu]/([Ga] + [In]) 1), and at the end of the process. Particular attention has been devoted to grain boundary composition and Na atomic distribution within the CIGSe layer. Significant variation of composition is highlighted during the growing process, providing fundamental information helping the understanding of high efficiency CIGSe formation.

  18. Nanodispositivos baseados em grafeno

    OpenAIRE

    José Eduardo Padilha de Sousa

    2012-01-01

    Nesta tese investigamos a partir de cálculos de primeiros princípios, dispositivos e componentes de dispositivos baseados em grafeno. Abordamos os campos da nanoeletrônica e da spintrônica. Dentro da nanoeletrônica investigamos: (i) propriedades de transporte de um nanotransistor de bicamada de grafeno na presença de um gate duplo. Demonstramos que sobre a ação de um campo elétrico externo, mesmo utilizando um gate da ordem de 10 nm, à temperatura ambiente e 4.5K uma corrente nula nunca é exi...

  19. Sade em Lacan

    OpenAIRE

    Riaviz, Eduardo

    2000-01-01

    Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Comunicação e Expressão. Esta dissertação analisa o lugar do Marquês de Sade no ensino de Lacan. Começamos por reconstruir a recepção de Sade pela vanguarda francesa, particularmente no movimento surrealista e nos seus dissidentes. Em seguida, acompanhamos as modificações do lugar de Sade na obra de Lacan. Para isto nos orientamos nos seis paradigmas do gozo através dos quais J.-A. Miller ordena a doutrina lacaniana...

  20. Flashes em Circuito

    Directory of Open Access Journals (Sweden)

    Ivete Lara Camargos Walty

    2002-12-01

    Full Text Available Reflexão sobre o papel da narrativa urbana no tratamento do tema da exclusão social, tendo como ponto de partida uma leitura do livro Passaporte, de Fernando Bonassi, que envolve a discussão do próprio gênero, a partir, sobretudo, da teoria do conto de Ricardo Piglia e de sua retomada das Seis propostas para o próximo milênio, de Ítalo Calvino, em artigo recente.

  1. Perspectives on EM metamaterials

    Directory of Open Access Journals (Sweden)

    Christophe Caloz

    2009-03-01

    Full Text Available Electromagnetic (EM metamaterials have become a field of intense research activities. This paper presents a critical perspective of the field, with emphasis on fundamental concepts and practical applications. Metamaterials are explained in the general context of periodic structures. Resonant particle type and transmission line type metamaterials are compared, and their fundamental connection is established. Exotic phenomena recently reported and associated challenges are briefly reviewed. Practical applications are enumerated and illustrated by an example. The paper concludes with an optimistic outlook regarding the future of metamaterials.

  2. Anestesia Diploica em Endodontia

    OpenAIRE

    Macedo, Ricardo Ribeiro Veiga de

    2013-01-01

    Trabalho final do 5º ano com vista à atribuição do grau de mestre no âmbito do ciclo de estudos de Mestrado Integrado em Medicina Dentária apresentado à Faculdade de Medicina da Universidade de Coimbra. Objetivos Comparar a eficácia das técnicas de anestesia convencionais, a anestesia infiltrativa periapical, com a anestesia diploica. Metodologia Foram selecionados 32 voluntários, saudáveis, aos quais foram administradas ambas as técnicas anestésicas no dente 1.4. Numa primeira fase os...

  3. Perossomus elumbis em bovino

    OpenAIRE

    1986-01-01

    Relato de um caso de distocia fetal em uma fêmea bovina mestiça Holandesa)Gir, provocado pela presença do monstro fetal Perossomus elumbis. Foi observado que o monstro fetal apresentava agenesia de vértebras lombares e coccígeas, com hi-poplasia da medula vertebral, terminando na região das últimas vértebras torácicas. A pelve apresentava-se hipoplásica com estreitamento do canal pélvico e anquilose dos membros posteriores e articulações da bacia, bem como atrofia muscular.  

  4. A New Benzofuran Derivative from <em>Flemingia philippinensisem> Merr. et Rolfe

    Directory of Open Access Journals (Sweden)

    Hua Li

    2012-06-01

    Full Text Available A new prenylated benzofuran derivative, named flemiphilippinone A, was isolated together with ten known flavonoids from the roots of <em>Flemingia philippinensisem>. Flemiphilippinone A was identified as (2<em>S>,3a<em>S>-5-(1-hydroxy-3-(4-methoxyphenyl- propylidene-2-(2-hydroxypropan-2-yl-3a,7-bis(3-methylbut-2-en-1-yltetrahydrobenzo- furan-4,6(2<em>H>,5<em>H>-dione, and its structure was established by a combination of HR EIMS, 1H-NMR, 13C-NMR, HMQC, HMBC and NOESY spectra data.

  5. Physiological response of Cu and Cu mine tailing remediation of Paulownia fortunei (Seem) Hemsl.

    Science.gov (United States)

    Jiang, Zao-Fa; Huang, Su-Zhen; Han, Yu-Lin; Zhao, Jiu-Zhou; Fu, Jia-Jia

    2012-04-01

    The physiological responses and Cu accumulation of Paulownia fortunei (Seem) Hemsl. were studied under 15.7-157 μmol L(-1) Cu treatments in liquid culture for 14 days; the impacts of Cu concentration in the seedlings were evaluated under Cu mine tailing culture with acetic acid and EDTA treatment for 60 days. Results showed that the concentrations of Chl-a, Chl-b and Carotenoids significantly increased (p tailing experienced unsuccessful growth and loss of leaves in all treatments due to poor nutrition of the Cu tailing. The dry weight of P. fortunei increased under all the treatments of acetic acid after 60 days exposure. However, dry weight significantly decreased under both levels of EDTA. The Cu concentrations increased significantly in roots and decreased in leaves when each was treated with both concentrations of acetic acid. The Cu concentrations in the roots, stems and leaves increased significantly, and the concentrations of Cu in the stems and leaves under the treatment of 2 μmol L(-1) EDTA reached 189.5 and 763.1 μg g(-1) DW, respectively. The result indicated that SOD, CAT, proline and soluble sugars played an important role in coping with the oxidative stress of copper. Acetic acid could promote growth and EDTA at the experimental levels, which could also enhance Cu absorption and translocation into the stems and leaves of P. fortune. Furthermore, acetic acid and EDTA could be rationally utilized in Cu-contaminated soil.

  6. Facile synthesis of dendritic Cu by electroless reaction of Cu-Al alloys in multiphase solution

    Science.gov (United States)

    Wang, Ying; Liang, Shuhua; Yang, Qing; Wang, Xianhui

    2016-11-01

    Two-dimensional nano- or micro-scale fractal dendritic coppers (FDCs) were synthesized by electroless immersing of Cu-Al alloys in hydrochloric acid solution containing copper chloride without any assistance of template or surfactant. The FDC size increases with the increase of Al content in Cu-Al alloys immersed in CuCl2 + HCl solution. Compared to Cu40Al60 and Cu45Al55 alloys, the FDC shows hierarchical distribution and homogeneous structures using Cu17Al83 alloy as the starting alloy. The growth direction of the FDC is , and all angles between the trunks and branches are 60°. Nanoscale Cu2O was found at the edge of FDC. Interestingly, nanoporous copper (NPC) can also be obtained through Cu17Al83 alloy. Studies showed that the formation of FDC depended on two key factors: the potential difference between CuAl2 intermetallic and α-Al phase of dual-phase Cu-Al alloys; a replacement reaction that usually occurs in multiphase solution. The electrochemical experiment further proved that the multi-branch dendritic structure is very beneficial to the proton transfer in the process of catalyzing methanol.

  7. Evaluation of Cu Ion Concentration Effects on Cu Etching Rate in Chemical-Mechanical Polishing Slurry

    Science.gov (United States)

    Nishizawa, Hideaki; Sugiura, Osamu; Matsumura, Yoshiyuki; Kinoshita, Masaharu

    2007-04-01

    The effects of Cu ion concentration of the different solutions on Cu etching rate were investigated. From the dipping experiment of Cu substrates in different solutions of malic acid, hydrogen peroxide (H2O2), benzotriazole (BTA), and Cu ions, it was revealed that Cu etching rate is increased if the concentration of Cu(II) ions added in the solution is high. This is considered to be caused by the effect of Cu(II) ions on H2O2 molecules. In the solution of pH 7, the Cu etching rate increased markedly between 1.7× 10-4 and 3.4× 10-4 M Cu(II) ion concentrations. The maximum increase in the etching rate was from 990 to 2200 nm/min at a H2O2 concentration of 2 wt %. In the solution of pH 3, a marked change in the etching rate was not observed. Our results show that the concentration of Cu ions on the polishing pad in chemical-mechanical polishing (CMP) process is very important.

  8. Effect of Corrosion Inhibitor, Benzotriazole, in Cu Slurry on Cu Polishing

    Science.gov (United States)

    Kim, In-Kwon; Kang, Young-Jae; Kim, Tae-Gon; Park, Jin-Goo

    2008-01-01

    In this study, the effect of benzotriazole (BTA) in Cu slurry on Cu polishing behavior was investigated as functions of H2O2 and slurry pH. The addition of BTA to slurry effectively prevented Cu from being etched by forming a passivation layer of Cu-BTA regardless of pH and H2O2 concentration in the slurry. The passivation layer on the Cu wafer exhibited a contact angle of 50° in solution with BTA and H2O2. The dynamic etching rate, i.e., the Cu polishing rate using abrasive-free slurry, also decreased when BTA was added to the slurry at pH 2, 4, and 6. The removal rate of Cu in slurry without BTA was strongly dependent on H2O2 concentration and pH. In slurry with BTA, Cu-BTA on the Cu surface prevented the etching of Cu. At pH 2 and 4, the removal rates were lower in slurry with BTA than in slurry without BTA. However, slurries of pH 6 or higher with BTA showed higher removal rates at higher concentrations of H2O2 than 10%, which was explained by the thick passivating oxide layer formed at higher pH and H2O2 concentrations.

  9. Characterization of Cu-exchanged SSZ-13: a comparative FTIR, UV-Vis, and EPR study with Cu-ZSM-5 and Cu-β with similar Si/Al and Cu/Al ratios.

    Science.gov (United States)

    Giordanino, Filippo; Vennestrøm, Peter N R; Lundegaard, Lars F; Stappen, Frederick N; Mossin, Susanne; Beato, Pablo; Bordiga, Silvia; Lamberti, Carlo

    2013-09-21

    Cu-SSZ-13 has been characterized by different spectroscopic techniques and compared with Cu-ZSM-5 and Cu-β with similar Si/Al and Cu/Al ratios and prepared by the same ion exchange procedure. On vacuum activated samples, low temperature FTIR spectroscopy allowed us to appreciate a high concentration of reduced copper centres, i.e. isolated Cu(+) ions located in different environments, able to form Cu(+)(N2), Cu(+)(CO)n (n = 1, 2, 3), and Cu(+)(NO)n (n = 1, 2) upon interaction with N2, CO and NO probe molecules, respectively. Low temperature FTIR, DRUV-Vis and EPR analysis on O2 activated samples revealed the presence of different Cu(2+) species. New data and discussion are devoted to (i) [Cu-OH](+) species likely balanced by one framework Al atom; (ii) mono(μ-oxo)dicopper [Cu2(μ-O)](2+) dimers observed in Cu-ZSM-5 and Cu-β, but not in Cu-SSZ-13. UV-Vis-NIR spectra of O2 activated samples reveal an intense and finely structured d-d quadruplet, unique to Cu-SSZ-13, which is persistent under SCR conditions. This differs from the 22,700 cm(-1) band of the mono(μ-oxo)dicopper species of the O2 activated Cu-ZSM-5, which disappears under SCR conditions. The EPR signal intensity sets Cu-β apart from the others.

  10. Pesquisa e desenvolvimento em cerâmicas eletro-eletrônicas no IPEN

    Directory of Open Access Journals (Sweden)

    Muccillo R.

    1999-01-01

    Full Text Available O Grupo de Cerâmicas Eletro-eletrônicas do IPEN desenvolve trabalhos de pesquisa em materiais cerâmicos avançados para utilização em dispositivos sensores de espécies químicas e em células de combustíveis a eletrólitos sólidos. As principais áreas de atuação do grupo são em 1 síntese, processamento e caracterização elétrica de materiais cerâmicos, 2 estudo de correlação microestrutura-propriedades elétricas de materiais cerâmicos, 3 projeto, desenvolvimento, montagem e testes de sensores eletroquímicos de espécies químicas. Os principais materiais estudados são condutores iônicos (à base de ZrO2, ThO2 e outros, protônicos (à base de BaCeO3, varistores à base de SnO2, supercondutores cerâmicos de alta temperatura crítica (das famílias Y-Ba-Cu-O e Bi-Sr-Ca-Cu-O e compósitos de matriz cerâmica (dos tipos isolante em matriz condutora iônica e condutor iônico em matriz supercondutora. A infra-estrutura experimental dispõe de analisador de impedância, difratômetro de raios X, equipamento de análise térmica simultânea, fornos para sinterização e laboratório químico. O trabalho de pesquisa do Grupo é financiado por projetos FAPESP e PRONEX.

  11. OBTENTION METHODS OF RESPIRATORY TRACT CELSS IN HEALTHY SHEEP BY THE TRACHEOBRONCHEAL LAVAGE TECHNIQUE BY NASOTRACHEAL VIA METODOLOGIA DE COLHEITA DE CÉLULAS DO TRATO RESPIRATÓRIO EM OVINOS SADIOS ATRAVÉS DA TÉCNICA DE LAVAGEM TRAQUEOBRÔNQUICA POR VIA NASOTRAQUEAL

    Directory of Open Access Journals (Sweden)

    Roberto Calderon Gonçalves

    2008-07-01

    Full Text Available

    The technique of pulmonary cells obtention by nasotracheal intubation was evaluated and the cellular population of 19 healthy sheep was characterized. The animals were hold standing still with head and neck strait; aligned with the vertebral spine and a silicone tube guide till the carina, to introduce a lower caliber tube for precede the tracheobronchial lavage. The average counting of nucleated cells was 64.650 ± 49.674. The cytological analyses of the samples slowed by the average of obtained percentages: 62.74% of macrophages, 15.01% cylindrical epithelial cells, 20.04% of neutrophills, 1.44 of lymphocytes and 0.77% of eosinophills. It was concluded that this methods of sample obtention by nasotracheal intubation to reach the tracheobronchial region was efficient to cytological characterization and cellular differentiation in the obtained samples, being well supported by the animals.

     

    KEY WORDS: Citocentrifugation, cytology, tracheobronchial lavage, sheep.

    Avaliou-se a técnica de colheita de células do trato respiratório em ovinos, por sondagem nasotraqueal, e caracterizou-se a população celular em dezenove ovinos clinicamente sadios. Os animais foram contidos em estação, com cabeça e pescoço estendidos e alinhados com a coluna vertebral. Após a contenção, introduziu-se uma sonda-guia siliconizada até a bifurcação da traquéia, por dentro da qual se passou uma sonda de menor calibre, para realização do lavado traqueobrônquico. A média da contagem de células nucleadas foi de 64.650 ± 49.674. A análise citológica das amostras evidenciou, pelas médias das porcentagens obtidas, 62,74% de macrófagos, 15,01% de células epiteliais cilíndricas, 20,04% de neutrófilos, 1,44% de linfócitos e 0,77% de eosinófilos. Concluiu-se que o método de colheita por sondagem nasotraqueal foi eficiente na obtenção de amostras de regi

  12. O insight em psiquiatria

    Directory of Open Access Journals (Sweden)

    Ana Margarida P. Cardoso

    2008-12-01

    Full Text Available O sinal de que algo está a acontecer contribui para que o paciente reconheça que alguma coisa de estranho se está a passar consigo. Este reconhecimento faz com que o sujeito possa desempenhar uma função activa e seja um elemento colaborante do seu processo de recuperação. Cada doença apresenta, contudo, diferentes sintomas, uma vez que cada doença psiquiátrica consiste em diferentes perturbações com diversos efeitos sobre o funcionamento mental. Desta maneira, o fenómeno do insight que é registado em cada doença é diferente e expressa-se sob diferentes formas, não somente devido às manifestações clínicas da doença mas também devido às características individuais do sujeito.

  13. Antibioticos profilaticos em neurocirurgia

    Directory of Open Access Journals (Sweden)

    Reynaldo A. Brandt

    1979-03-01

    Full Text Available O índice de infecções pós-operatórias em pacientes neuro-cirúrgicos que receberam antibióticos profiláticos neste período foi comparado com o de pacientes que não receberam antibióticos. Infecções ocorreram em proporções significativamente maiores nos pacientes que receberam antibióticos, particularmente naqueles com afecções intracranianas graves; estas infecções foram graves e fatais na maioria dos casos. A administração de antibióticos profiláticos nestes pacientes não só foi incapaz de prevenir o aparecimento de infecções pós-operatórias, como aparentemente favoreceu o seu desenvolvimento. Tal se deveu, provavelmente, à destruição do equilíbrio microbiano no organismo, favorecendo o desenvolvimento de germes patogênicos e resistentes aos antibióticos usuais

  14. COMPOSIÇÃO MINERAL, SANIDADE E QUALIDADE DE MAÇÃS EM POMARES CONVENCIONAIS E ORGÂNICOS

    Directory of Open Access Journals (Sweden)

    JOÃO JOSÉ STÜPP

    2015-03-01

    Full Text Available RESUMO O objetivo deste trabalho foi avaliar os efeitos dos sistemas de manejo convencional e orgânico sobre a composição mineral, sanidade e qualidade de maçãs das cultivares Royal Gala e Fuji. O estudo foi realizado em São Joaquim-SC, nas safras de 2008/2009 e 2009/2010, em um Cambissolo Húmico. O manejo orgânico, em ambas as cultivares, aumentou a área foliar média e específica e os teores foliares de K e Cu, e em ‘Royal Gala’ aumentou o Ca foliar.Na maturação comercial, frutos orgânicos apresentaram maiores valores de percentual de cor vermelha na epiderme, firmeza de polpa, danos por mosca-das-frutas, teores de Cu e relações K/Ca, Mg/Ca e (K+Mg/Ca na polpa, em ambas as cultivares, e de teor de K na polpa em ‘Royal Gala’. As plantas no sistemaorgânico apresentaram valores inferiores de teores foliares de clorofila e N, rendimento, incidência de frutos comsarna da macieira, bem como frutos com menores teores de sólidos solúveis e de Ca na polpa, em ambas as cultivares, menores danos por queimadura de sol em ‘Royal Gala’ e menor teor de K na casca dos frutos em‘Fuji’. A produção orgânica de maçãs pode ser viável, porém necessita da adoção de tecnologia eficaz para o controle de danos por mosca-das-frutas.

  15. Microstructures and properties of Cr-Cu/W-Cu bi-layer composite coatings prepared by mechanical alloying

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jiaping; Feng, Xiaomei; Shen, Yifu; Chen, Cheng; Duan, Cuiyuan [Nanjing Univ. of Aeronautics and Astronautics (China). Dept. of Materials Science and Technology

    2016-06-15

    Cr-Cu/W-Cu bi-layer coatings with composite structures were fabricated by means of mechanical alloying. The Cr-Cu layer and the W-Cu layer were deposited successively and the as-synthesized bi-layer coating was made up of an inner Cr-Cu layer and an outer W-Cu layer. Microstructures, chemical and phase compositions of the as-prepared coatings were characterized. The results indicated that the bonding between the inner coating and the substrate was improved with the increase of Cu in the raw powder. The annealing treatment of the inner Cr-Cu layer was beneficial to the bonding between the inner Cr-Cu coating and the outer W-Cu coating layer. Mechanical properties such as microhardness, friction and wear resistance were tested. The as-synthesized coating could effectively improve the hardness and wear resistance of the Cu substrate.

  16. Mixed-valence copper coordination polymers based on CuSCN or CuN3 as bridging motifs

    Institute of Scientific and Technical Information of China (English)

    FAN Guang; GAO Shengli; CHEN Sanping; ZENG Minghua; XIE Gang

    2005-01-01

    Two novel mixed valence copper coordination polymers, [Cu(2-pac)2(CuN3)(H2O)]n (1) and [Cu(2-pac)2(CuSCN)2]n (2), have been prepared through hydrothermal synthesis and analyzed for structure determination, which exhibit two- and three-dimensional structures respectively. In complex (1), zigzag chains of [CuN3]n running parallel to the c direction are interconnected by Cu(2pac)2 to form a two-dimensional layer structure. In complex (2), the arrangement of μ-1,1,3 bridging thiocyanate ligand leads to the formation of ten-membered Cu-SCN- Cu-S-Cu-NCS rings, and each Cu atom is further linked by Cu(2-pac)2 to afford a three-dimensional configuration.

  17. Desempenho de catalisadores com Nb2O5 para produção de hidrogênio a partir da reforma de etanol com vapor d’água

    Directory of Open Access Journals (Sweden)

    Nádia Regina Camardo Fernandes Machado

    2002-04-01

    Full Text Available Reforma de etanol com vapor d’água, para produção de hidrogênio, foi estudada sobre catalisadores Cu/Nb2O5 e Cu/Nb2O5/Al2O3. Eles foram preparados por impregnação, com diferentes concentrações de cobre e Nb2O5. Um catalisador comercial, Cu/ZnO/Al2O3 (G66, de reforma do metanol, foi usado para comparação. Dados de redução à temperatura programada mostraram incompleta redução do cobre, com formação de dois picos de redução diferentemente do CuO mássico, cuja redução ocorre em uma única etapa (somente um pico, evidenciando que o cobre é modificado ao ser suportado sobre Nb2O5. Resultados de espectroscopia de reflectância difusa também evidenciam a interação. Testes catalíticos mostraram que a dispersão do pentóxido de nióbio sobre alumina melhorou a ação do catalisador, uma vez que os catalisadores ternários são os que apresentam maior produção de hidrogênio, apesar de também produzirem éter etílico como subproduto. Os catalisadores binários não catalisam reações paralelas, provavelmente, porque, quando Cu/Nb2O5 está disperso sobre alumina, há formação de um novo sítio ativo o qual produz éter etílico.

  18. Direct synthesis of RGO/Cu{sub 2}O composite films on Cu foil for supercapacitors

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Xiangmao; Wang, Kun [Key Laboratory for Ultrafine Materials of the Ministry of Education, Shanghai Key Laboratory of Advanced Polymeric Materials, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai 200237 (China); Zhao, Chongjun, E-mail: chongjunzhao@ecust.edu.cn [Key Laboratory for Ultrafine Materials of the Ministry of Education, Shanghai Key Laboratory of Advanced Polymeric Materials, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai 200237 (China); Institute for Superconducting and Electronic Materials, University of Wollongong, Wollongong 2500 (Australia); Qian, Xiuzhen [Key Laboratory for Ultrafine Materials of the Ministry of Education, Shanghai Key Laboratory of Advanced Polymeric Materials, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai 200237 (China); Chen, Shi [School of Information Engineering, Wuhan University of Technology, Wuhan 430070 (China); Li, Zhen, E-mail: zhenl@uow.edu.au [Institute for Superconducting and Electronic Materials, University of Wollongong, Wollongong 2500 (Australia); Liu, Huakun; Dou, Shixue [Institute for Superconducting and Electronic Materials, University of Wollongong, Wollongong 2500 (Australia)

    2014-02-15

    Graphical abstract: RGO/Cu{sub 2}O/Cu composites were synthesized by simple hydrothermal treatment of copper foils with graphene oxide, in which the reduction of graphene oxide and the formation of Cu{sub 2}O nanoparticles simultaneously happened in one-pot reaction. These composites can be directly used as electrodes of supercapacitors with the highest specific capacitance of 98.5 F/g at 1 A g{sup −1}, which is much better than that of CuO or Cu{sub 2}O electrodes. -- Highlights: • The RGO/Cu{sub 2}O/Cu composites were obtained by a friendly method in one step. • Improved capacitance performance is realized by the hydrothermal treatment of graphene oxides with Cu foils. • RGO/Cu{sub 2}O/Cu-200 composites exhibit the largest specific capacitance of 98.5 F g{sup −1} at 1 A g{sup −1}. -- Abstract: Reduced graphene oxide/cuprous oxide (RGO/Cu{sub 2}O) composite films were directly synthesized on the surface of copper foil substrates through a straight redox reaction between GO and Cu foil via a hydrothermal approach. Characterization of the resultant composites with X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, and field emission scanning electron microscope (FESEM) confirms the formation of Cu{sub 2}O and reduction of GO, in which Cu{sub 2}O nanoparticles were well covered by RGO. The resultant composites (referred to as RGO/Cu{sub 2}O/Cu) were directly used as electrodes for supercapacitors, and their electrochemical performance was assessed by cyclic voltammetry (CV), galvanostatic charge–discharge (GCD), and electrochemical impedance spectrometry (EIS) in 1 M KOH aqueous solution. A specific capacitance of 98.5 F g{sup −1} at 1 A g{sup −1} was obtained, which is much higher than that of pure Cu{sub 2}O prepared under the same conditions, due to the presence of RGO.

  19. <em>Ipomoea aquaticaem> Extract Shows Protective Action Against Thioacetamide-Induced Hepatotoxicity

    OpenAIRE

    Hadi, A. Hamid A.; Siddig Ibrahim Abdelwahab; Suzy Munir Salama; Salim Said Alkiyumi; Mahmood Ameen Abdullah; Ahmed Salim Alrashdi

    2012-01-01

    In the Indian system of traditional medicine (Ayurveda) it is recommended to consume <em>Ipomoea em>aquatica> to mitigate disorders like jaundice. In this study, the protective effects of ethanol extract of <em>I. aquaticaem> against liver damage were evaluated in thioacetamide (TAA)-induced chronic hepatotoxicity in rats. There was no sign of toxicity in the acute toxicity study, in which Sprague-Dawley (SD) rats were orally fed with <em>...

  20. Four Novel Cellulose Synthase (CESA Genes from <em>Birch> (<em>Betula platyphylla em>Suk. Involved in Primary and Secondary Cell Wall Biosynthesis

    Directory of Open Access Journals (Sweden)

    Xuemei Liu

    2012-09-01

    Full Text Available Cellulose synthase (CESA, which is an essential catalyst for the generation of plant cell wall biomass, is mainly encoded by the <em>CesA> gene family that contains ten or more members. In this study; four full-length cDNAs encoding CESA were isolated from<em> Betula platyphyllaem> Suk., which is an important timber species, using RT-PCR combined with the RACE method and were named as <em>BplCesA3em>, <em>−4em>,> −7 em>and> −8em>. These deduced CESAs contained the same typical domains and regions as their <em>Arabidopsis> homologs. The cDNA lengths differed among these four genes, as did the locations of the various protein domains inferred from the deduced amino acid sequences, which shared amino acid sequence identities ranging from only 63.8% to 70.5%. Real-time RT-PCR showed that all four <em>BplCesAs> were expressed at different levels in diverse tissues. Results indicated that BplCESA8 might be involved in secondary cell wall biosynthesis and floral development. BplCESA3 appeared in a unique expression pattern and was possibly involved in primary cell wall biosynthesis and seed development; it might also be related to the homogalacturonan synthesis. BplCESA7 and BplCESA4 may be related to the formation of a cellulose synthase complex and participate mainly in secondary cell wall biosynthesis. The extremely low expression abundance of the four BplCESAs in mature pollen suggested very little involvement of them in mature pollen formation in <em>Betula>. The distinct expression pattern of the four <em>BplCesAs> suggested they might participate in developments of various tissues and that they are possibly controlled by distinct mechanisms in <em>Betula.>

  1. Giant electric conductivity in CuO-Cu interface and its HTSC-like temperature changes

    CERN Document Server

    Osipov, V V; Naumov, S V

    2001-01-01

    The temperature dependences of the electric conductivity and volt-ampere characteristics (VAC) of the samples, representing the CuO monocrystals, the natural facets whereof are coated with the Cu film, are studied. It is shown that the electric conductivity, related to the Cu films, after electro-chemical or thermal annealing grows multiply up to 1.5 x 10 sup 5 times as compared to the Cu control films on the devitrified glass. The obtained results are explained by formation of the high-conductivity interface layer between CuO and Cu. It is supposed that the giant electric conductivity, its HTSC-like change with the temperature and VAC nonlinearity may be conditioned by formation of superconducting areas with critical temperatures, essentially exceeding 400 K

  2. Effect of reducing agents in the conversion of Cu2O nanocolloid to Cu nanocolloid

    Directory of Open Access Journals (Sweden)

    V. Andal

    2017-02-01

    Full Text Available Current work reports the conversion of copper (I oxide, nano-colloid to stable copper nanocolloid. Different reduction conditions were attempted to control the stability and size of the Cu nanoparticles. Hydrazine hydrate, ascorbic acid and glucose are found to be good reductants. In our work stable copper nanoparticles are obtained by reducing Cu2O without any special protections like inert gas atmosphere etc. Ascorbic acid, a natural vitamin C not only reduces cuprous oxide but protects the new born copper due to its antioxidant properties. A red shift is observed when Cu2O nanospheres get converted to Cu. UV, XRD, FTIR and TEM were used to characterize the prepared Cu nanoparticles. The mechanism for the growth process of Cu nanomaterials are discussed.

  3. <em>N>-Substituted 5-Chloro-6-phenylpyridazin-3(2<em>H>-ones: Synthesis, Insecticidal Activity Against <em>Plutella xylostella em>(L. and SAR Study

    Directory of Open Access Journals (Sweden)

    Song Yang

    2012-08-01

    Full Text Available A series of <em>N>-substituted 5-chloro-6-phenylpyridazin-3(2<em>H>-one derivatives were synthesized based on our previous work; all compounds were characterized by spectral data and tested for <em>in vitroem> insecticidal activity against <em>Plutella xylostellaem>. The results showed that the synthesized pyridazin-3(2<em>H>-one compounds possessed good insecticidal activities, especially the compounds 4b, 4d, and 4h which showed > 90% activity at 100 mg/L. The structure-activity relationships (SAR for these compounds were also discussed.

  4. Ferromagnetic Cu-O-Cu coupling in CaCu3Sn4O12 probed by neutron diffraction.

    Science.gov (United States)

    Kayser, P; Retuerto, M; Sánchez-Benítez, J; Martínez-Lope, M J; Fernández-Díaz, M T; Alonso, J A

    2012-12-12

    The A-site ordered perovskite oxide with the formula CaCu(3)Sn(4)O(12) has been synthesized in polycrystalline form under moderate pressure conditions (3.5 GPa) in combination with high temperature (1000 °C). This oxide crystallizes in the cubic space group [Formula: see text] (no. 204) with the unit-cell parameter a = 7.64535(6) Å at 300 K. The SnO(6) network is extremely tilted, giving rise to a square planar coordination for Cu(2+) cations. The non-magnetic character of Sn(4+) offers an excellent opportunity to probe the magnetism of Cu(2+) at the A sublattice in CaCu(3)Sn(4)O(12). Magnetic susceptibility shows that this compound is ferromagnetic below T(C) = 10 K, which is an unusual magnetic behaviour in cuprates. This peculiar aspect has been examined by neutron powder diffraction. The refinement of the magnetic structure at 4 K indeed indicates a parallel coupling between Cu(2+) spins with a magnetic moment of 0.5 μ(B)/Cu atom.

  5. Fitoextração de cobre por espécies de plantas cultivadas em solução nutritiva

    Directory of Open Access Journals (Sweden)

    Ariana Carramaschi Francato Zancheta

    2011-01-01

    Full Text Available Dentre as tecnologias para remediação de solos contaminados, destaca-se a fitoextração. Uma etapa importante nesta estratégia é a seleção de plantas adequadas para áreas que necessitam de recuperação. O objetivo deste trabalho foi avaliar o potencial fitoextrator de cobre (Cu por plantas de sorgo (Sorghum bicolor, milheto (Pennisetum glaucum, crotalária (Crotalaria juncea e feijão-de-porco (Canavalia ensiformis. O delineamento experimental foi em blocos ao acaso e os tratamentos foram constituídos de quatro concentrações de Cu (0,8; 3,9; 19,7 e 98,4 µmol L-1 na solução nutritiva. Após 30 dias do início dos tratamentos, foram realizadas medidas de trocas gasosas em folhas completamente expandidas. Em seguida, as plantas foram coletadas, separadas em parte aérea e sistema radicular para avaliação de crescimento e acúmulo de Cu. O tratamento com 98,4 µmol L-1 de Cu na solução nutritiva inibiu marcadamente o acúmulo de massa seca da parte aérea das raízes das plantas. A condutância estomática, transpiração e assimilação de CO2 não foram alteradas até o tratamento com 19,7 µmol L-1 de Cu. O teor e acúmulo de Cu nas plantas foram proporcionais à adição do metal na solução nutritiva, porém, foram muito mais elevados no sistema radicular do que na parte aérea. O acúmulo preferencial de Cu nas raízes, embora diminua o transporte para a parte aérea e contribua para a tolerância das plantas ao metal, é limitante para o emprego da fitoextração. O feijão-de-porco teve maior concentração, acúmulo e transporte de Cu para a parte aérea, sendo uma espécie com potencial para ser utilizada em programas de fitorremediação de Cu.

  6. COMPOSIÇÃO CENTESIMAL E MINERAL DA ALFARROBA EM PÓ E SUA UTILIZAÇÃO NA ELABORAÇÃO E ACEITABILIDADE EM SORVETE

    Directory of Open Access Journals (Sweden)

    Daiane Rebeca SABATINI

    2011-01-01

    Full Text Available Alfarroba (Ceratonia siliqua L. é uma leguminosa arbórea tropical comum no semi-árido, que se desenvolve em lugares secos, onde difi cilmente outras plantas poderiam sobreviver. Suas vagens produzem uma farinha que pode ser usada na alimentação humana, semelhante ao cacau. Este trabalho teve por objetivos determinar a composição centesimal e o conteúdo mineral da alfarroba em pó, bem como avaliar a viabilidade da alfarroba na elaboração e aceitabilidade de um sorvete. Os resultados demonstraram que a alfarroba em pó é rica em carboidratos (76,6%, rica em proteínas (4,79%, pobre em lipídios (0,48% e apresenta alto teor de fi bras (5,68%. Com relação aos minerais analisados, o conteúdo de K, Cu, Fe e Mn atendem com mais de 20% das DRIs para um adulto. O sorvete elaborado foi avaliado sensorialmente por 127 provadores não treinados utilizando a escala hedônica (de “gostei extremamente” a “desgostei extremamente”, com relação aos atributos aparência, sabor, textura e aspecto global. O índice de aceitabilidade foi superior a 87% para todos os atributos, indicando a boa aceitabilidade do produto desenvolvido. Desta forma, conclui-se que a alfarroba em pó pode ser utilizada como ingrediente na elaboração de sorvetes, contribuindo no desenvolvimento de novos produtos alimentícios.

  7. INFLUÊNCIA ESTOICA NA CONCEPÇÃO DE <em>STATUS> E <em>DICTUM> COMO <em> QUASI RES EM> (ὡσανεì τινά) EM ABERLARDO STOIC INFLUENCE IN ABELARD'S CONCEPTION OF <em>STATUS> AND <em>DICTUM> AS <em>QUASI RESem> (ὡσανεì τινά).

    OpenAIRE

    Guy Hamelin

    2011-01-01

    Na sua obra, Pedro Abelardo (1079-1142) destaca duas noções metafísicas que fundamentam sua teoria lógica: o <em style="mso-bidi-font-style: normal;">statusem> e o <em style="mso-bidi-font-style: normal;">dictum propositionisem>, ao causar, respectivamente, a imposição (<em style="mso-bidi-font-style: normal;">impositioem>) dos termos universais e o valor de verdade das proposições. Trata-se de expressões que se referem a naturezas ontológicas peculia...

  8. Tube drawing technology for seamless pipes. Application to the Cu/Nb/Cu sandwiched pipes

    Energy Technology Data Exchange (ETDEWEB)

    Tsukada, Saburo; Ohnuki, Masao [Hitachi Cable, Ltd., Tsuchiura, Ibaraki (Japan); Fujino, Takeo; Saito, Kenji; Inoue, Hitoshi; Hitomi, Nobuteru; Yamazaki, Yoshishige [High Energy Accelerator Research Organization, Tsukuba, Ibaraki (Japan); Watanabe, Kakuji [Okuda Kinzoku Co. Ltd., Ota, Fukui (Japan)

    2001-02-01

    Tube drawing technology based on copper tubes at the Hitachi Cable Corporation was applied to manufacture Cu/Nb/Cu sandwiched seamless pipes for Nb/Cu clad superconducting RF cavities, which is being developed at KEK. This is the first application in our company. We met several problems but finally succeeded to fabricate 11 pipes needed to hydro-bulge forming for 1300 MHz single cell cavities. Here, we explain this technology and report the problems which happened during the manufacturing. (author)

  9. Structural Stabilities of Ordered Nb4 Clusters on the Cu(111) and Cu(100) Surfaces

    Institute of Scientific and Technical Information of China (English)

    WANG Xiao-Chun; ZHU Zi-Zhong

    2007-01-01

    @@ Based on first-principles calculations, we show that very high-density periodic arrays of Nb4 clusters with both the tetrahedron and quadrangle configurations can be stably absorbed on the Cu(111) and Cu(100) surfaces,with the quadrangle configurations more stable than the tetrahedron ones. The strong covalent bonding between atoms within the Nb4 clusters contributes to the stability of Nb4 adsorptions on the Cu surfaces.

  10. Fisioterapia motora em pacientes adultos em terapia intensiva

    OpenAIRE

    Borges,Vanessa Marcos; Oliveira,Luiz Rogério Carvalho de; Peixoto,Elzo; Carvalho, Nilza Aparecida de Almeida

    2009-01-01

    O objetivo desse estudo é realizar uma revisão da literatura abordando o tema fisioterapia motora para pacientes adultos em unidade de terapia intensiva. A busca de artigos científicos foi realizada nas bases de dados PubMed, MedLine (Literatura Internacional em Ciências e Saúde), LILACS (Literatura Latino Americana e do Caribe em Ciências e Saúde) e Cochrane entre 1995 e dezembro de 2008 utilizando as palavras-chaves: physical therapy, mobilization and intensive care unit. Para efeito de com...

  11. Cu2ZnSiS4

    Directory of Open Access Journals (Sweden)

    Kimberly A. Rosmus

    2011-04-01

    Full Text Available Single crystals of Cu2ZnSiS4, dicopper(I zinc silicon tetrasulfide, have been prepared via high-temperature solid-state synthesis. Cu2ZnSiS4 was found to have the wurtz-stannite structure type, like that of Li2CdGeS4, Li2CdSnS4, and Cu2CdSiS4. Each sulfur anion is tetrahedrally coordinated by two Cu cations, one Si cation, and one Zn cation, forming a three-dimensional honeycomb structure. When viewed along the c axis, the atoms are aligned in rows in which each cation alternates with the sulfur anions.

  12. Temperature stability of AgCu nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Sopoušek, Jiří, E-mail: sopousek@mail.muni.cz; Zobač, Ondřej; Vykoukal, Vít [Masaryk University, Department of Chemistry, Faculty of Science (Czech Republic); Buršík, Jiří; Roupcová, Pavla [Institute of Physics of Materials ASCR (Czech Republic); Brož, Pavel; Pinkas, Jiří [Masaryk University, Department of Chemistry, Faculty of Science (Czech Republic); Vřešťál, Jan [Masaryk University, Central European Institute of Technology, CEITEC (Czech Republic)

    2015-12-15

    The colloidal solutions of the Ag–Cu nanoparticles (NPs, 10–32 nm) were prepared by solvothermal reactions. The samples of dried AgCu NPs and the resulting microstructures after heat treatment in air were investigated by various methods including electron microscopy (TEM, SEM) and high-temperature X-ray powder diffraction (HTXRD). The AgCu randomly mixed, Cu-rich, and Ag-rich face centred cubic crystal lattices were detected during the experiments. The temperature induced sintering was observed experimentally by HTXRD at 250 °C. The phase transformations at high temperatures were monitored by differential scanning calorimetry. The formation of the Ag-rich grains during heating in air and evolution of copper oxide microstructure were detected.Graphical abstract.

  13. W-WSi/sub 2/-Cu system

    Energy Technology Data Exchange (ETDEWEB)

    Efimov, Yu.V.; Frolova, T.M.; Bodak, O.I.; Kharchenko, O.I. (AN SSSR, Moscow. Inst. Metallurgii)

    1984-09-01

    Ternary system W-Si-Cu in the region up to 60 at.%(Si+Cu) has been investigated. Using the methods of metallographic and X-ray analyses of alloys in the system considered no new ternary compounds are detected. The major area of phase diagram of the ternary system studied is occupied by three-phase regions (W+W/sub 5/Si/sub 3/+..cap alpha..) and (W/sub 5/Si/sub 3/+WSi/sub 2/+..cap alpha..). Solid solution on copper basis (..cap alpha..-phase) occupies a narrow region, adjoining the system Cu-Si. Alloys, containing up to 3 at.%Si and 0.5 at.%Cu in cast and annealed states present solid solutions on tungsten basis. With the increase in silicon and copper content the second phase is separated.

  14. Acúmulo de nutrientes em frutos de cafeeiro em duas altitudes de cultivo: micronutrientes Nutrient accumulation in coffee fruits at two at two plantation altitudes: micronutrients

    Directory of Open Access Journals (Sweden)

    Bruno Galvêas Laviola

    2007-12-01

    Full Text Available Dado à importância de se conhecer a exportação de micronutrientes pelos frutos, bem como, as épocas em que são mais demandados pelo cafeeiro, estudou-se o acúmulo de B, Cu, Fe, Mn e Zn em frutos de Coffea arabica L da antese à maturação, em lavouras estabelecidas em duas altitudes. Estudou-se também a variação no teor desses elementos. Estudou-se o acúmulo de B, Cu, Fe, Mn e Zn em frutos de cafeeiro arábico da antese à maturação em duas altitudes, bem como a variação na concentração dos elementos em folhas dos ramos produtivos. O experimento foi constituído da variedade de cafeeiro (Coffea arabica L. Catuaí IAC 44 cultivada a 720 e 950 m de altitude, no município de Martins Soares-MG. O delineamento experimental foi inteiramente ao acaso, com três repetições, usando um esquema de parcela subdividida no tempo. O aumento da altitude influenciou o ciclo reprodutivo do cafeeiro, demandando maior tempo para formação dos frutos. O consumo de nutrientes pelos frutos, assim como o enchimento de grãos, foi mais crítico em condições de menor altitude, já que a planta necessitou completar esses processos em menor espaço de tempo. No estádio de expansão rápida, a percentagem de acúmulo de micronutrientes foi maior na altitude de 720 m, comparada à de 950 m. De modo geral, a altitude influenciou a variação das concentrações foliares de nutrientes, apesar de não se ter observado resposta-padrão da concentração foliar ao aumento da altitude. Conclui-se que a altitude teve influência na extensão do ciclo, bem como no acúmulo de micronutrientes em frutos e na variação, das concentrações foliares destes elementos em folhas de cafeeiro.In view of the importance of knowing fruit micronutrients export from the soil, and the season in which its coffee-plant demand is higher, the accumulation of B, Cu, Fe, Mn and Zn in fruits as well as the variation in the leaf content of the elements in productive branches of

  15. Osteoporose em caprinos

    Directory of Open Access Journals (Sweden)

    Fábio B. Rosa

    2013-04-01

    Full Text Available Foi realizado um estudo de casos de osteoporose em caprinos provenientes de uma propriedade na área de abrangência do LPV-UFSM, determinando a epidemiologia, o quadro clínico-patológico e discutindo os prováveis mecanismos patogenéticos. Cinco cabras, fêmeas, SRD, de seis meses a seis anos de idade foram afetadas. As cabras eram mantidas em campo nativo, sem suplementação com ração e sob superlotação. Os principais sinais clínicos foram emagrecimento, dificuldade de locomoção e permanência em decúbito por longos períodos. As principais alterações macroscópicas nos ossos examinados foram vistas nas superfícies de corte e caracterizavam-se por depleção do osso esponjoso (porosidade e redução acentuada da espessura do osso cortical. Havia também marcada atrofia serosa da gordura da medula óssea. Microscopicamente, nas regiões avaliadas (úmero proximal, rádio distal, fêmur distal, tíbia proximal e corpos das vértebras lombares foi observada redução moderada a acentuada do número e da espessura das trabéculas ósseas nas epífises e metáfises dos ossos longos e nos corpos vertebrais. Os achados clínico-patológicos indicaram que a osteoporose observada provavelmente foi causada pela desnutrição. As alterações ósseas (diminuição no número e na espessura das trabéculas do osso esponjoso sugerem que ambos os mecanismos, má formação óssea e reabsorção óssea aumentada, contribuíram para a ocorrência de osteoporose nos caprinos deste estudo.

  16. Coupling of electron transfer with proton transfer at heme a and Cu(A) (redox Bohr effects) in cytochrome c oxidase. Studies with the carbon monoxide inhibited enzyme.

    Science.gov (United States)

    Capitanio, N; Capitanio, G; Minuto, M; De Nitto, E; Palese, L L; Nicholls, P; Papa, S

    2000-05-30

    A study is presented on the coupling of electron transfer with proton transfer at heme a and Cu(A) (redox Bohr effects) in carbon monoxide inhibited cytochrome c oxidase isolated from bovine heart mitochondria. Detailed analysis of the coupling number for H(+) release per heme a, Cu(A) oxidized (H(+)/heme a, Cu(A) ratio) was based on direct measurement of the balance between the oxidizing equivalents added as ferricyanide to the CO-inhibited fully reduced COX, the equivalents of heme a, Cu(A), and added cytochrome c oxidized and the H(+) released upon oxidation and all taken up back by the oxidase upon rereduction of the metal centers. One of two reductants was used, either succinate plus a trace of mitochondrial membranes (providing a source of succinate-c reductase) or hexaammineruthenium(II) as the chloride salt. The experimental H(+)/heme a, Cu(A) ratios varied between 0.65 and 0.90 in the pH range 6.0-8.5. The pH dependence of the H(+)/heme a, Cu(A) ratios could be best-fitted by a function involving two redox-linked acid-base groups with pK(o)-pK(r) of 5.4-6.9 and 7.3-9.0, respectively. Redox titrations in the same samples of the CO-inhibited oxidase showed that Cu(A) and heme a exhibited superimposed E'(m) values, which decreased, for both metals, by around 20 mV/pH unit increase in the range 6.0-8.5. A model in which oxido-reduction of heme a and Cu(A) are both linked to the pK shifts of the two acid-base groups, characterized by the analysis of the pH dependence of the H(+)/heme a, Cu(A) ratios, provided a satisfactory fit for the pH dependence of the E'(m) of heme a and Cu(A). The results presented are consistent with a primary involvement of the redox Bohr effects shared by heme a and Cu(A) in the proton-pumping activity of cytochrome c oxidase.

  17. Effects of tensile stress on Cu clustering in irradiated Fe–Cu alloy

    Energy Technology Data Exchange (ETDEWEB)

    Fujii, K., E-mail: fujiik@inss.co.jp [Institute of Nuclear Safety System, Inc., Mihama 919-1205 (Japan); Fukuya, K. [Institute of Nuclear Safety System, Inc., Mihama 919-1205 (Japan); Kasada, R.; Kimura, A. [Institute of Advanced Energy, Kyoto University, Uji 611-0011 (Japan); Ohkubo, T. [National Institute for Materials Science, Tsukuba 305-0047 (Japan)

    2015-03-15

    Effects of tensile stress on Cu clustering were explained using atom probe tomography (APT) results of Fe–0.6 wt.%Cu alloy specimens irradiated with 6.4 MeV Fe ions while applying a tensile stress of 60 MPa at room temperature (less than 50 °C) and 290 °C. The hardening under the tensile-stressed irradiation was smaller than that under the stress-free irradiation at both room temperature and 290 °C. APT results showed that well-defined Cu clusters were formed in all specimens even under the room temperature irradiation. The Cu clusters under the tensile-stressed condition were smaller and had higher densities than those under the stress-free condition. The lower Cu content in clusters and more diffuse Cu clustering were obtained for the specimens irradiated under the tensile-stressed condition. The hardening efficiency of Cu clusters was correlated with the Cu content in clusters and the coherency of interface between a cluster and the matrix. Application of tensile stress would control hardening by changing the nature of Cu clusters.

  18. Computer simulations of nanoindentation in Mg-Cu and Cu-Zr metallic glasses

    DEFF Research Database (Denmark)

    Paduraru, Anca; Andersen, Ulrik Grønbjerg; Thyssen, Anders

    2010-01-01

    The formation of shear bands during plastic deformation of Cu0.50Zr0.50 and Mg0.85Cu0.15 metallic glasses is studied using atomic-scale computer simulations. The atomic interactions are described using realistic many-body potentials within the effective medium theory, and are compared with similar...... simulations using a Lennard-Jones description of the material. The metallic glasses are deformed both in simple shear and in a simulated nanoindentation experiment. Plastic shear localizes into shear bands with a width of approximately 5 nm in CuZr and 8 nm in MgCu. In simple shear, the shear band formation...

  19. Enhanced Cu-to-Cu direct bonding by controlling surface physical properties

    Science.gov (United States)

    Chiang, Po-Hao; Liang, Sin-Yong; Song, Jenn-Ming; Huang, Shang-Kun; Chiu, Ying-Ta; Hung, Chih-Pin

    2017-03-01

    Cu-to-Cu direct bonding is one of the key technologies for three-dimensional (3D) chip stacking. This research proposes a new concept to enhance Cu-to-Cu direct bonding through the control of surface physical properties. A linear relationship between bonding strength and the H/\\sqrt{R} value of the bonding face (H: subsurface hardness, R: surface roughness) was found. Low vacuum air plasma and thermal annealing were adopted to adjust the surface physical conditions. Instead of surface activation, an acceleration in copper atom diffusion due to plasma-induced compressive stress accounts for the improvement in bonding strength.

  20. Synthesis of MOF templated Cu/CuO@TiO2 nanocomposites for synergistic hydrogen production.

    Science.gov (United States)

    Mondal, Indranil; Pal, Ujjwal

    2016-02-14

    A copper metal-organic framework (Cu-MOF) provides access to Cu/CuO@TiO2 hybrid nanocomposites with highly dispersive copper species adsorbed on a TiO2 semiconducting system. This novel nanostructure exhibits efficient hydrogen evolution performance under solar illumination of intensity ∼1 Sun. The rate of H2 production was systematically optimized under different operational parameters. Experimental observation reveals that mesoporous Cu/CuO@TiO2 nanocomposite with 0.5 wt% Cu loading showed the highest rate of H2 production (286 mmol g(-1) h(-1)), which is considerably higher than that of CuO loaded TiO2 prepared using a conventional impregnation method. This high photocatalytic H2 production activity is attributed predominantly to the presence of surface deposited Cu(0) species and the small size of the heterojunction (1-2 nm) between CuO and TiO2, which facilitate interfacial charge carrier transfer from the TiO2 nanoparticles. The catalyst showed good recyclability under prolonged exposure (30 h) to solar irradiation. Unlike many Pt decorated TiO2 photocatalysts, this hybrid photocatalyst provides an inexpensive means of harnessing solar energy.

  1. Electromigration in 3D-IC scale Cu/Sn/Cu solder joints

    Energy Technology Data Exchange (ETDEWEB)

    Ho, Cheng-En, E-mail: ceho1975@hotmail.com; Lee, Pei-Tzu; Chen, Chih-Nan; Yang, Cheng-Hsien

    2016-08-15

    The electromigration effect on the three-dimensional integrated circuits (3D-IC) scale solder joints with a Cu/Sn(25–50 μm)/Cu configuration was investigated using a field-emission scanning electron microscope (FE–SEM) combined with electron backscatter diffraction (EBSD) analysis system. Electron current stressing for a few days caused the pronounced accumulation of Cu{sub 6}Sn{sub 5} in specific Sn grain boundaries (GBs). The EBSD analysis indicated that both the β-Sn crystallographic orientation and GB orientation play dominant roles in this accumulation. The dependencies of the Cu{sub 6}Sn{sub 5} accumulation on the two above factors (i.e., Sn grain orientation and GB orientation) can be well rationalized via a proposed mathematic model based on the Huntington and Grone's electromigration theory with the Cu anisotropic diffusion data in a β-Sn lattice. - Highlights: • Anisotropic Cu electromigration in the 3D-IC scale microelectronic solder joints. • Pronounced accumulation of Cu{sub 6}Sn{sub 5} intermetallic in specific Sn grain boundaries. • A linear dependence of Cu{sub 6}Sn{sub 5} accumulation over the current stressing time. • β-Sn and grain boundary orientations are the dominant factors in Cu{sub 6}Sn{sub 5} accumulation.

  2. Métodos de determinação da disponibilidade de cobre em substratos Copper availability determination in substrates

    Directory of Open Access Journals (Sweden)

    Alceu L Padua Junior

    2008-06-01

    Full Text Available Para melhorar a qualidade das plantas produzidas em ambientes protegidos ou semi-protegidos é de fundamental importância a adoção de materiais inertes ou pouco alterados que exerçam a função de solo. Esses materiais são chamados de substratos e apresentam as mais variadas origens e composições, podendo ser orgânicos, minerais ou sintéticos. Dentre os problemas nutricionais, a falta ou o excesso de cobre (Cu é um dos que mais têm afetado a produção de mudas. Portanto, o objetivo desta pesquisa foi de avaliar métodos que sejam eficientes em determinar o Cu disponível em substrato. O experimento foi conduzido em casa de vegetação, usando os substratos à base de fibra de coco, casca de pinus e turfa e a rúcula (Eruca sativa L. como planta teste. Todos os substratos receberam cinco doses de cobre (0; 0,5; 1,0; 2,0 e 3,0 mg de Cu por dm³ de substrato. Após a colheita da rúcula retirou-se uma amostra de substrato para extração de Cu usando os seguintes métodos: (DTPA pH a 2,6, (DTPA + trietanolamina a pH 7,3, HNO3 + H2O2 a 30%, K4P2O7 e (NaOCl a pH 8,5 + DTPA. As soluções ácidas apresentaram maior capacidade extrativa de Cu para todos os substratos testados. Na análise individual por substrato, somente a fibra de coco apresentou valores de R² significativos para todos os métodos. Na análise conjunta dos substratos, todos os métodos apresentaram coeficientes de determinação significativos (R²> 0,51, mostrando que esses métodos poderão ser utilizados na avaliação da disponibilidade de Cu em substratos.To improve the quality of plants grown under protected or semi-protected environments it is very important to adopt inert or less altered materials to use as soilless media. These materials, called substrates, depending on its origin could be organic, mineral, or synthetic. Among the nutritional problems, the lack or excess of copper (Cu has been the main factor affecting seedling production. The objective of this

  3. AVALIAÇÃO DO POTENCIAL FITORREMEDIADOR DE PLANTAS FLORÍFERAS EM SOLO CONTAMINADO COM COBRE

    OpenAIRE

    Janine Farias Menegaes

    2015-01-01

    A contaminação do solo é um problema ambiental, social e econômico. Em áreas vitivinícolas, como as da Serra Gaúcha, o uso prolongado de produtos fitossanitários, a base de cobre, contribuiu para o acúmulo deste elemento no solo, quando em excesso é altamente prejudicial ao desenvolvimento das plantas, impactando no seu potencial produtivo. Visando minimizar o efeito nocivo do Cu nos solos destas áreas, o presente trabalho objetivou avaliar o cultivo e o potencial de extração d...

  4. Quel accompagnement infirmier pour la personne âgée à domicile, dans une perspective de placement en EMS?

    OpenAIRE

    Hofmann Hausammann, Sonia

    2008-01-01

    L'objectif de cette étude est de dégager des pistes de réflexion permettant d'améliorer la prise en charge à domicile des personnes âgées devant aller en EMS, en répondant aux questions suivantes: -Quel est le vécu de la personne âgée qui doit être placée en EMS? -Comment l'accompagnement infirmier est-il perçu par la personne âgée? Le jury a notamment relevé la richesse du cadre théorique.

  5. Beta-decay of Cu-56

    NARCIS (Netherlands)

    Ramdhane, M; Baumann, P; Knipper, A; Walter, G; Janas, Z; Plochocki, A; Aysto, J; Dendooven, P; Jokinen, A; Oinonen, M; Pentila, H; Liu, W; Gorska, M; Grawe, H; Hu, Z; Kirchner, R; Klepper, O; Roeckl, E; Fujita, Y; Brown, BA

    1998-01-01

    By measuring positrons and P-delayed gamma-rays emitted from mass-separated sources, the decay of Cu-56 (4(+),T-z = -1,T = 1) to states in the doubly-magic nucleus Ni-56 was Studied for the first time. The half-life of Cu-56 was measured to be 78(15) ms, and four beta-delayed gamma-rays were assigne

  6. V-Ge-Cu system

    Energy Technology Data Exchange (ETDEWEB)

    Savitskij, E.M.; Efimov, Yu.V.; Bodak, O.I.; Kharchenko, O.I.; Shomova, N.A.; Frolova, T.M.

    By the methods of microscopic, X-ray phase analyses, X-ray spectral microanalysis as well as by measurement of Tsub(C) and phase lattice parameters the structure of the vanadium-region of the V-Ge ternary system (up to 40 at.%) - Cu(up to 90 at.%) is studied and isothermal cross section at 800 deg C is plotted. In the studied region solid solutions on the base of vanadium, copper and V/sub 3/Ge and V/sub 5/Ge/sub 3/ compounds are in phase equilibria. The solid solution on the vanadium base in ternary alloys practically does not possess superconductivity at the temperature over 4.2 K. Tsub(C) of V/sub 3/Ge saturated with copper decreases up to 5.3-5.6 K depending on treatment conditions and alloys composition. The superspeed quenching from molten state and the consequent low-temperature tempering of ternary alloys can increase V/sub 3/Ge Tsub(C) up to 6-6.7 K.

  7. Dissolution and Interfacial Reactions of (Cu,Ni)6Sn5 Intermetallic Compound in Molten Sn-Cu-Ni Solders

    Science.gov (United States)

    Wang, Chao-hong; Lai, Wei-han; Chen, Sinn-wen

    2014-01-01

    (Cu,Ni)6Sn5 is an important intermetallic compound (IMC) in lead-free Sn-Ag-Cu solder joints on Ni substrate. The formation, growth, and microstructural evolution of (Cu,Ni)6Sn5 are closely correlated with the concentrations of Cu and Ni in the solder. This study reports the interfacial behaviors of (Cu,Ni)6Sn5 IMC (Sn-31 at.%Cu-24 at.%Ni) with various Sn-Cu, Sn-Ni, and Sn-Cu-Ni solders at 250°C. The (Cu,Ni)6Sn5 substrate remained intact for Sn-0.7 wt.%Cu solder. When the Cu concentration was decreased to 0.3 wt.%, (Cu,Ni)6Sn5 significantly dissolved into the molten solder. Moreover, (Cu,Ni)6Sn5 dissolution and (Ni,Cu)3Sn4 formation occurred simultaneously for the Sn-0.1 wt.%Ni solder. In Sn-0.5 wt.%Cu-0.2 wt.%Ni solder, many tiny (Cu,Ni)6Sn5 particulates were formed and dispersed in the solder matrix, while in Sn-0.3 wt.%Cu-0.2 wt.%Ni a lot of (Ni,Cu)3Sn4 grains were produced. Based on the local equilibrium hypothesis, these results are further discussed based on the liquid-(Cu, Ni)6Sn5-(Ni,Cu)3Sn4 tie-triangle, and the liquid apex is suggested to be very close to Sn-0.4 wt.%Cu-0.2 wt.%Ni.

  8. ABSORÇÃO E ACUMULAÇÃO DE NUTRIENTES EM ESTÉVIA Stevia rebaudiana (Bert. Bertoni: II. MICRONUTRIENTES

    Directory of Open Access Journals (Sweden)

    Lima Filho O.F. de

    1997-01-01

    Full Text Available Estudou-se a absorção e o acúmulo de micronutrientes pela estévia, em condições de cultivo comercial no campo. Foram avaliados dois índices nutricionais: Taxa de Absorção Relativa do Nutriente e Taxa de Acumulação Líquida Organogênica do Nutriente. Foram realizadas 7 coletas a cada 15 dias a partir do transplante. Pouco antes ou no início do florescimento, a produção de 1 tonelada de folhas secas exigiu, em g: B-89; Cu-26; Fe-638; Mn-207; Zn-13. Para a produção de sementes, correspondente a 1 tonelada de folhas secas, a extração de micronutrientes, em g, foi: B-226; Cu-76; Fe-2550; Mn-457; Zn-33.

  9. INFLUÊNCIA ESTOICA NA CONCEPÇÃO DE <em>STATUS> E <em>DICTUM> COMO <em> QUASI RES EM> (ὡσανεì τινά EM ABERLARDO STOIC INFLUENCE IN ABELARD'S CONCEPTION OF <em>STATUS> AND <em>DICTUM> AS <em>QUASI RESem> (ὡσανεì τινά.

    Directory of Open Access Journals (Sweden)

    Guy Hamelin

    2011-09-01

    Full Text Available Na sua obra, Pedro Abelardo (1079-1142 destaca duas noções metafísicas que fundamentam sua teoria lógica: o <em style="mso-bidi-font-style: normal;">statusem> e o <em style="mso-bidi-font-style: normal;">dictum propositionisem>, ao causar, respectivamente, a imposição (<em style="mso-bidi-font-style: normal;">impositioem> dos termos universais e o valor de verdade das proposições. Trata-se de expressões que se referem a naturezas ontológicas peculiares, na medida em que não são consideradas coisas (<em style="mso-bidi-font-style: normal;">resem>, mesmo que constituem causas. Todavia, também não são nada. Abelardo as chama de ‘quase coisas’ (<em style="mso-bidi-font-style: normal;">quasi resem>. No presente artigo, explicamos, primeiro, essas duas noções essenciais da lógica abelardiana, antes de tentar, em seguida, encontrar a fonte dessa metafísica particular. Em oposição a comentadores importantes da lógica de Abelardo, que estimam que haja uma forte influência platônica sobre essa concepção específica, defendemos antes, com apoio de textos significativos e de acordo com o nominalismo abelardiano, que a maior ascendência sobre a metafísica do nosso autor é a do estoicismo, sobretudo, antigo.In his work, Peter Abelard (1079-1142 highlights two metaphysical notions, which sustain his logical theory: the <em>status> and the <em>dictum propositionisem>, causing respectively both the imposition (<em>impositio> of universal terms and the thuth-value of propositions. Both expressions refer to peculiar ontological natures, in so far as they are not considered things (<em>res>, even if they constitute causes. Nevertheless, neither are they ‘nothing’. Abelard calls them ‘quasi-things’ (<em>quasi resem>. In the present article, we expound first these two essential notions of Abelardian logic before then trying to find the source of this particular metaphysics. Contrary to some important

  10. Em favor da talassografia

    Directory of Open Access Journals (Sweden)

    Jean-Louis Boudou

    2001-01-01

    Full Text Available A Talassografia (“descrição do mar” interessa-sepelos impactos físicos, biológicos, ecológicos... culturais da violenta antropização dos ambientes costeiros (oceânicos e continentais, caracterizados pelaexigüidade, vulnerabilidade, fragilidade e plasticidade. Como o Brasil é um “país marítimo”, os geó-grafos (os talassógrafos brasileiros são convidadosa intensificar suas pesquisas nas áreas costeiras e acriar novas estruturas para divulgá-las: Revista, Encontros, Associação, Pós-Graduação... tudo em prolda talassografia.

  11. Constrangimentos posturais em ergonomia

    OpenAIRE

    Silva, Cláudio Roberto de Carvalho

    2001-01-01

    Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia de Produção. A incorporação da Ergonomia no projeto e gerenciamento do consultório odontológico é fundamental, com o objetivo de adequar e adaptar o trabalho ao cirurgião dentista. Neste trabalho de pesquisa, a aplicação de conceitos atuais da Ergonomia se fez necessária para que fosse possível a obtenção de dados para uma análise apurada com relação às posturas ad...

  12. Iatrogenia em cardiologia

    OpenAIRE

    Pereira,Afonso Celso; Franken,Roberto Alexandre; Sprovieri,Sandra Regina Schwarzwalder; Golin,Valdir

    2000-01-01

    O termo iatrogenia vem do grego e refere-se a qualquer alteração patológica provocada no paciente pela má prática médica. Infelizmente, o risco de sua ocorrência convive constantemente no manuseio das doenças cardíacas. Podem ser considerados dois tipos de iatrogenia: iatrogenia de ação, ou decorrente da ação médica, e iatrogenia de omissão, relacionada à falta de ação do médico. As iatrogenias ocorrem em todas as fases do ato médico, desde a relação com o paciente, passando pelo diagnóstico,...

  13. Constrangimentos posturais em ergonomia

    OpenAIRE

    Silva, Cláudio Roberto de Carvalho

    2001-01-01

    Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia de Produção. A incorporação da Ergonomia no projeto e gerenciamento do consultório odontológico é fundamental, com o objetivo de adequar e adaptar o trabalho ao cirurgião dentista. Neste trabalho de pesquisa, a aplicação de conceitos atuais da Ergonomia se fez necessária para que fosse possível a obtenção de dados para uma análise apurada com relação às posturas ad...

  14. Marcas culturais em interface

    OpenAIRE

    Mazutti, Sandra

    2011-01-01

    Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Comunicação e Expressão, Programa de Pós-Graduação em Estudos da Tradução A cultura é fator determinante para a língua e, portanto, para todos os atos de compreensão e interpretação da mesma. Língua e cultura estão intrinsecamente interligadas, fazendo parte da identidade não só individual, mas também da sociedade como um todo. Permeando tal relação encontramos o tradutor, que assume o papel de intermediador cultura...

  15. Bullyng em jovens LGBT

    OpenAIRE

    Pimenta, Neuza Santos; Martins, Emíla orient.

    2013-01-01

    O bullying homofóbico é uma forma específica de assédio que ocorre quando a vitimização é motivada pelo preconceito homossexual. Os jovens alunos, lésbicas, gays, bissexuais e transsexuais (LGBT), vítimas desta forma de bullying estão mais vulneráveis à exclusão social, isolamento e aquisição de comportamentos de risco. O presente projeto de investigação pretende contribuir para a compreensão de questões relacionadas com os episódios de bullying em jovens LGBT, sempre na per...

  16. Compression of klockmannite, CuSe

    Science.gov (United States)

    Peiris, Suhithi M.; Pearson, Tania T.; Heinz, Dion L.

    1998-07-01

    Copper selenide (CuSe) was compressed in a diamond anvil cell at room temperature up to a pressure of 52 GPa and studied using energy dispersive x-ray diffraction and Raman spectroscopy. CuSe is nearly isostructural with copper sulfide (CuS), and a previous study indicates that copper sulfide undergoes reversible pressure-induced amorphization at 18 GPa. The intensity of the x-ray diffraction peaks for CuSe decrease slowly, however, they never completely disappear up to a pressure of 52 GPa. The third-order Birch-Murnaghan equation of state fit to the data yields K0=96.9±5.3 GPa and K0'=4.1±0.5. Vinet's universal equation of state yields essentially identical parameters. Raman spectroscopy demonstrates that upon compression, the S-S bond in CuS compresses differently than the Se-Se bond in CuSe, possibly accounting for the different high pressure behavior of these two very similar compounds.

  17. Antimicrobial Cu-bearing stainless steel scaffolds.

    Science.gov (United States)

    Wang, Qiang; Ren, Ling; Li, Xiaopeng; Zhang, Shuyuan; Sercombe, Timothy B; Yang, Ke

    2016-11-01

    Copper-bearing stainless steel scaffolds with two different structures (Body Centered Cubic and Gyroid labyrinth) at two solid fractions (25% and 40%) were fabricated from both 316L powder and a mixture of 316L and elemental Cu powder using selective laser melting, and relative 316L scaffolds were served as control group. After processing, the antimicrobial testing demonstrated that the 316L-Cu scaffolds presented excellent antimicrobial activity against Escherichia coli and Staphylococcus aureus, and the cell viability assay indicated that there was no cytotoxic effect of 316L-Cu scaffolds on rat marrow mesenchymal stem cells. As such, these have the potential to reduce implant-associated infections. The Cu was also found to homogeneously distribute within the microstructure by scanning electronic microcopy. The addition of Cu would not significantly affect its strength and stiffness compared to 316L scaffold, and the stiffness of all the scaffolds (3-20GPa) is similar to that of bone and much less than that of bulk stainless steel. Consequently, fabrication of such low stiffness porous structures, especially coupled with the addition of antimicrobial Cu, may provide a new direction for medical stainless steels.

  18. Spectroscopic study of Cu{sup 2+} and Cu{sup +} ions in high-transmission glass. Electronic structure and Cu{sup 2+}/Cu{sup +} concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, Susana; Rodriguez, Fernando [MALTA-CONSOLIDER-Team, DCITIMAC, Facultad de Ciencias, Universidad de Cantabria, 39005 Santander (Spain); Urra, Inigo [Departmento Construccion, Area de Energia y medioambiente, CIDEMCO-Tecnalia, 20730 Azpeitia (Spain); Valiente, Rafael, E-mail: gomezss@unican.e [MALTA-CONSOLIDER-Team, Departmento Fisica Aplicada, Facultad de Ciencias, Universidad de Cantabria, 39005 Santander (Spain)

    2010-07-28

    This work investigates the formation of photoluminescence centres in high-transmission glass (HTG) doped with Cu{sub 2}O and their capability to transform the solar spectrum by absorption/emission via Stokes-shifted PL into a more efficient spectrum for photovoltaic applications. Among the centres formed in HTG, both green photoluminescent Cu{sup +} and the non-photoluminescent Cu{sup 2+} centres are created but their relative concentration depends on the thermal treatment and the presence of other co-dopants. The measurement of the absorption coefficient {alpha}({lambda}) nearby the HTG optical gap for Cu{sup +} bands is accomplished by following the two-thickness method. This procedure allows us to obtain the actual absorption coefficient for the spectrum of each formed centre, from which we obtain the relative concentration of Cu{sup +}/Cu{sup 2+} as well as their absolute values. The analysis of the spectra provides information on the absorption cross sections, transition energies and bandwidths, the knowledge of which is essential to check the suitability of such centres for photovoltaic applications in solar cells.

  19. On diffusion of Cu in ZnO

    Energy Technology Data Exchange (ETDEWEB)

    Herklotz, F., E-mail: frank.herklotz@physik.tu-dresden.d [Institut fuer Angewandte Physik, Technische Universitaet Dresden, 01062 Dresden (Germany); Lavrov, E.V.; Weber, J. [Institut fuer Angewandte Physik, Technische Universitaet Dresden, 01062 Dresden (Germany)

    2009-12-15

    An experimental study of Cu diffusion in bulk ZnO single crystals in the temperature range 1012-1220 deg. C is presented. Concentration profiles of substitutional Cu were determined by IR absorption at 5817cm{sup -1}. Our findings reveal that Cu in ZnO diffuses faster than previously reported [G. Mueller, R. Helbig, J. Phys. Chem. Solids 32 (1971) 1971]. The discrepancy is tentatively explained by the formation of Cu complexes, which occurs at high Cu concentrations.

  20. Short and Long-Term Effects of <em>Baccharis articulataem> on Glucose Homeostasis

    Directory of Open Access Journals (Sweden)

    Flávio H. Reginatto

    2012-06-01

    Full Text Available In this study, the<em> in vivoem> effect of the crude extract and <em>n>-butanol and aqueous residual fractions of <em>Baccharis articulataem> (Lam. Pers. on serum glucose levels, insulin secretion and liver and muscle glycogen content, as well as<em> in vitroem> action on serum intestinal disaccharidase activity and albumin glycation were investigated. Oral administration of the extract and fractions reduced glycemia in hyperglycemic rats. Additionally, the <em>n>-butanol fraction, which has high flavonoids content, stimulated insulin secretion, exhibiting an insulinogenic index similar to that of glipizide. Also, the <em>n>-butanol fraction treatment significantly increased glycogen content in both liver and muscle tissue. <em>In vitroem> incubation with the crude extract and <em>n>-butanol and aqueous residual fractions inhibited maltase activity and the formation of advanced glycation end-products (AGEs. Thus, the results demonstrated that <em>B. articulataem> exhibits a significant antihyperglycemic and insulin-secretagogue role. These effects on the regulation of glucose homeostasis observed for <em>B. articulataem> indicate potential anti-diabetic properties.

  1. Morphology, structure, and properties of Cu-poor and Cu-rich Cu(In,Ga)Se2 films partially selenized using H2Se gas

    Science.gov (United States)

    Han, Anjun; Huang, Yongliang; Liu, Xiaohui; Xian, Wang; Meng, Fanying; Liu, Zhengxin

    2016-11-01

    Cu-poor and Cu-rich metallic precursors were prepared by cosputtering from In and Cu-Ga alloy targets and then partially selenized using H2Se gas. The properties of Cu(In,Ga)Se2 (CIGS) films are comparatively studied and the phase transition process is analyzed. The cosputtered metallic precursor has a rough morphology mostly covered by large In-rich nodules. After selenization, a large number of crumblike InSe grains were formed from the nodules on the surface of the Cu-rich film, whereas the Cu-poor film shows a dense surface. The selenized films comprise CIGS, Cu9(In,Ga)4 intermetallic, and the InSe phases. The proportion of the Cu9(In,Ga)4 phase in the Cu-rich film is more than that in the Cu-poor film. After annealing, the residual Cu9(In,Ga)4 of the Cu-poor film is eliminated. A negligible effect of Cu/(In+Ga) on the grain size can be observed. The CIGS solar cell with an efficiency of 15.1% was prepared by this method.

  2. Inhibiting the growth of Cu3Sn and Kirkendall voids in the Cu/Sn-Ag-Cu system by minor Pd alloying

    Science.gov (United States)

    Ho, Cheng En; Kuo, Tsai Tung; Wang, Chun Chien; Wu, Wei Hsiang

    2012-10-01

    In this study, the metallurgical reaction between Cu substrates (electrolytic type) and a Sn3Ag0.5Cu-xPd alloy at 180°C was examined using a scanning electron microscope (SEM), electron probe microanalyzer (EPMA), focused ion beam (FIB) microscope, and transmission electron microscope (TEM). The results showed that the growth of Cu3Sn in the Cu/Sn-Ag-Cu solder joints was substantially suppressed by doping with a minor quantity of Pd (0.1-0.7 wt. %) in the solder alloy. The sluggish growth of Cu3Sn reduced the formation of Kirkendall voids at the Cu/Cu3Sn interface and significantly improved the mechanical reliability of the joint interface. It was argued that a minor addition of Pd into the solder stabilized the Cu6Sn5 phase and enlarged the interdiffusion coefficient of Cu6Sn5 but diminished that of the neighboring phase (Cu3Sn), thereby decreasing the Kirkendall effect in the Cu/Sn-Ag-Cu reactive system.

  3. Investigation of the Phase Equilibria of Sn-Cu-Au Ternary and Ag-Sn-Cu-Au Quaternary Systems and Interfacial Reactions in Sn-Cu/Au Couples

    Science.gov (United States)

    Yen, Yee-Wen; Jao, Chien-Chung; Hsiao, Hsien-Ming; Lin, Chung-Yung; Lee, Chiapyng

    2007-02-01

    The phase equilibria of the Sn-Cu-Au ternary, Ag-Sn-Cu-Au quaternary systems and interfacial reactions between Sn-Cu alloys and Au were experimentally investigated at specific temperatures in this study. The experimental results indicated that there existed three ternary intermetallic compounds (IMCs) and a complete solid solubility between AuSn and Cu6Sn5 phases in the Sn-Cu-Au ternary system at 200°C. No quaternary IMC was found in the isoplethal section of the Ag-Sn-Cu-Au quaternary system. Three IMCs, AuSn, AuSn2, and AuSn4, were found in all couples. The same three IMCs and (Au,Cu)Sn/(Cu,Au)6Sn5 phases were found in all Sn-Cu/Au couples. The thickness of these reaction layers increased with increasing temperature and time. The mechanism of IMC growth can be described by using the parabolic law. In addition, when the reaction time was extended and the Cu content of the alloy was increased, the AuSn4 phase disappeared gradually. The (Au, Cu)Sn and (Cu,Au)6Sn5 layers played roles as diffusion barriers against Sn in Sn-Cu/Au reaction couple systems.

  4. Preferencia alimenticia del ácaro depredador <em>Balaustium> sp. en condiciones controladas

    Directory of Open Access Journals (Sweden)

    Muñoz Karen

    2009-04-01

    Full Text Available

    Se evaluó la preferencia de presas de <em>Balaustium> sp., enemigo natural de diferentes artrópodos plaga, y el cual es nativo de la Sabana de Bogotá. En unidades experimentales construidas con foliolos de plantas de rosa se colocaron independientemente individuos de <em>Balaustium> sp. y se registró el número de presas consumidas. De esta manera se determinó la preferencia de los tres estados móviles del ácaro depredador <em>Balaustium> sp. por diferentes edades de tres presas. Las especies y edades de las presas estudiadas fueron: huevos, ninfas y adultos de <em>Trialeurodes vaporariorumem>, huevos, ninfas y adultos de <em>Tetranychus urticaeem>, y larvas de primer y segundo instar y adultos de <em>Frankliniella occidentalisem>. Los estados menos desarrollados fueron preferidos, aunque se observó que los adultos del depredador tienen gran habilidad para consumir adultos de <em>T. vaporariorumem>. La presa preferida por las larvas de <em>Balaustium> sp. fue los huevos de <em>T. urticaeem> con una proporción de consumo de 0,54 de los huevos que se ofrecieron de esta presa; las deutoninfas del depredador eligieron huevos de <em>T. vaporariorumem> (0,537 o de <em>T. urticaeem> (0,497 y los adultos de <em>Balaustium> sp. prefrieron los huevos de <em>T. vaporariorumem> (0,588.

  5. Formation processes of CuCl and regenerated Cu crystals on bronze surfaces in neutral and acidic media

    Energy Technology Data Exchange (ETDEWEB)

    Wang Julin [Institute of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing 100029 (China)]. E-mail: julinwang@126.com; Xu Chunchun [Institute of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing 100029 (China); Lv Guocheng [Institute of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing 100029 (China)

    2006-07-15

    The paper is devoted to investigating the formation of CuCl and regenerated Cu crystals on bronze. Electrochemical behaviour of bronze in simulated anoxic edaphic media and occluded cell (O.C.) solutions was studied with cycle voltammetry (CV) and X-ray diffraction (XRD). Within potential range of -800 to +800 mV, oxidation occurred was largely a process in which Cu is oxidized to CuCl and the reduction process was a reverse of it. An atomic force microscopy (AFM) was used to observe the morphology of CuCl crystals, regenerated Cu crystals and corrosion interface at nm level. The deposition of regenerated Cu on simulated archaeological bronzes was simulated under experimental conditions for the first time. CuCl could be thoroughly reduced to pure Cu if reduction time interval were sufficiently prolonged. This provided a theoretical and experimental basis for getting rid of harmful CuCl patina from archaeological bronzes with electrochemical means.

  6. Quantas medidas de pressões respiratórias são necessárias para se obterem medidas máximas em pacientes com tetraplegia? ¿Cuántas maniobras son necesarias para llegar a las presiones máximas en pacientes con tetraplejía? How many maneuvers of respiratory pressures are required to obtain maximal values in patients with quadriplegia?

    OpenAIRE

    Ada Clarice Gastaldi; Getúlio Antonio de Freitas Filho; Ana Paula Manfio Pereira; Janne Marques Silveira

    2010-01-01

    INTRODUÇÃO: pressões inspiratórias (PImax) ou expiratórias (PEmax) máximas constituem um método simples e não-invasivo para avaliação da força de músculos respiratórios e auxiliam na identificação de fraqueza dos músculos respiratórios, presente em diversas doenças e situações clínicas, como a tetraplegia. OBJETIVO: avaliar o número de manobras necessárias para atingir as pressões máximas em pacientes com tetraplegia. MÉTODOS: oito pacientes com tetraplegia (sete homens), média de idade de 37...

  7. Extraction of Dihydroquercetin<em> em>from <em>Larix gmeliniem>i> em>with Ultrasound-Assisted and Microwave-Assisted Alternant Digestion

    Directory of Open Access Journals (Sweden)

    Yuangang Zu

    2012-07-01

    Full Text Available An ultrasound and microwave assisted alternant extraction method (UMAE was applied for extracting dihydroquercetin (DHQ from <em>Larix gmeliniem>i> wood. This investigation was conducted using 60% ethanol as solvent, 1:12 solid to liquid ratio, and 3 h soaking time. The optimum treatment time was ultrasound 40 min, microwave 20 min, respectively, and the extraction was performed once. Under the optimized conditions, satisfactory extraction yield of the target analyte was obtained. Relative to ultrasound-assisted or microwave-assisted method, the proposed approach provides higher extraction yield. The effect of DHQ of different concentrations and synthetic antioxidants on oxidative stability in soy bean oil stored for 20 days at different temperatures (25 °C and 60 °C was compared. DHQ was more effective in restraining soy bean oil oxidation, and a dose-response relationship was observed. The antioxidant activity of DHQ was a little stronger than that of BHA and BHT. Soy bean oil supplemented with 0.08 mg/g DHQ exhibited favorable antioxidant effects and is preferable for effectively avoiding oxidation. The <em>L. gmeliniiem> wood samples before and after extraction were characterized by scanning electron microscopy. The results showed that the UMAE method is a simple and efficient technique for sample preparation.

  8. Magnetron sputtered Cu{sub 3}N/NiTiCu shape memory thin film heterostructures for MEMS applications

    Energy Technology Data Exchange (ETDEWEB)

    Kaur, Navjot; Choudhary, Nitin [Indian Institute of Technology Roorkee, Roorkee, Functional Nanomaterials Research Lab, Department of Physics and Centre of Nanotechnology (India); Goyal, Rajendra N. [Indian Institute of Technology, Roorkee, Department of Chemistry (India); Viladkar, S. [Indian Institute of Technology Roorkee, Roorkee, Functional Nanomaterials Research Lab, Department of Physics and Centre of Nanotechnology (India); Matai, I.; Gopinath, P. [Indian Institute of Technology, Roorkee, Centre for Nanotechnology (India); Chockalingam, S. [Indian Institute of Technology, Guwahati, Department of Biotechnology (India); Kaur, Davinder, E-mail: dkaurfph@iitr.ernet.in [Indian Institute of Technology Roorkee, Roorkee, Functional Nanomaterials Research Lab, Department of Physics and Centre of Nanotechnology (India)

    2013-03-15

    In the present study, for the first time, Cu{sub 3}N/NiTiCu/Si heterostructures were successfully grown using magnetron sputtering technique. Nanocrystalline copper nitride (Cu{sub 3}N with thickness {approx}200 nm) thin films and copper nanodots were subsequently deposited on the surface of 2-{mu}m-thick NiTiCu shape memory thin films in order to improve the surface corrosion and nickel release properties of NiTiCu thin films. Interestingly, the phase transformation from martensite phase to austenite phase has been observed in Cu{sub 3}N/NiTiCu heterostructures with corresponding change in texture and surface morphology of top Cu{sub 3}N films. Field emission scanning electron microscopy and atomic force microscope images of the heterostructures reveals the formation of 20-nm-sized copper nanodots on NiTiCu surface at higher deposition temperature (450 Degree-Sign C) of Cu{sub 3}N. Cu{sub 3}N passivated NiTiCu films possess low corrosion current density with higher corrosion potential and, therefore, better corrosion resistance as compared to pure NiTiCu films. The concentration of Ni released from the Cu{sub 3}N/NiTiCu samples was observed to be much less than that of pure NiTiCu film. It can be reduced to the factor of about one-ninth after the surface passivation resulting in smooth, homogeneous and highly corrosion resistant surface. The antibacterial and cytotoxicity of pure and Cu{sub 3}N coated NiTiCu thin films were investigated through green fluorescent protein expressing E. coli bacteria and human embryonic kidney cells. The results show the strong antibacterial property and non cytotoxicity of Cu{sub 3}N/NiTiCu heterostructure. This work is of immense technological importance due to variety of BioMEMS applications.

  9. Espectrofotometria de zinco em fertilizantes em fluxo Flow injection spectrophotometry of zinc in mineral fertilizers

    Directory of Open Access Journals (Sweden)

    Arnaldo Antonio Rodella

    1999-07-01

    Full Text Available Um sistema de análise química por injeção em fluxo é proposto para a determinação espectrofotométrica de zinco em amostras de misturas de fertilizantes minerais, empregando-se zincon como reagente cromogênico. O procedimento analítico envolve redução de íons metálicos por ácido ascórbico, complexação com íon cianeto, seguindo-se a descomplexação seletiva do zinco com formaldeído, liberando-o para que reaja com o zincon formando um complexo azul. A aplicação do método proposto à extratos de mistura de fertilizantes indicou que a ação de interferentes pode ser contornada e que resultados comparáveis aos da espectrometria de absorção atômica são obtidos.A flow injection system for zinc analysis in mineral fertilizer mixtures is proposed using zincon as chromogenic reagent. The effect of interfering ions such as Cu2+, Fe3+, Mn2+ was eliminated by reduction (using ascorbic acid and complexation of these metal íons with cyanide, with zinc included. Zinc is allowed to react with zincon only after the destruction of the zinc cyano complex with formaldehyde. Flow injection analysis permitted efficient control of the reaction time so that only the zinc ion is set free to produce a blue complex with zincon. Zinc was determined in 16 fertilizer mixtures (3 replicates with precision and accuracy comparable to atomic absorption spectrometry.

  10. Atomically engineering Cu/Ta interfaces.

    Energy Technology Data Exchange (ETDEWEB)

    Webb, Edmund Blackburn, III (, Sandia National Laboratories, Albuquerque, NM); Zhou, Xiao Wang

    2007-09-01

    This report summarizes the major research and development accomplishments for the late start LDRD project (investment area: Enable Predictive Simulation) entitled 'Atomically Engineering Cu/Ta Interfaces'. Two ultimate goals of the project are: (a) use atomistic simulation to explore important atomistic assembly mechanisms during growth of Cu/Ta multilayers; and (b) develop a non-continuum model that has sufficient fidelity and computational efficiency for use as a design tool. Chapters 2 and 3 are essentially two papers that address respectively these two goals. In chapter 2, molecular dynamics simulations were used to study the growth of Cu films on (010) bcc Ta and Cu{sub x}Ta{sub 1-x} alloy films on (111) fcc Cu. The results indicated that fcc crystalline Cu films with a (111) texture are always formed when Cu is grown on Ta. The Cu films are always polycrystalline even when the Ta substrate is single crystalline. These polycrystalline films are composed of grains with only two different orientations, which are separated by either orientational grain boundaries or misfit dislocations. Periodic misfit dislocations and stacking fault bands are observed. The Cu film surface roughness was found to decrease with increasing adatom energy. Due to a Cu surface segregation effect, the Cu{sub x}Ta{sub 1-x} films deposited on Cu always have a higher Cu composition than that used in the vapor mixture. When Cu and Ta compositions in the films are comparable, amorphous structures may form. The fundamental origins for all these phenomena have been studied in terms of crystallography and interatomic interactions. In chapter 3, a simplified computational method, diffusional Monte Carlo (dMC) method, was developed to address long time kinetic processes of materials. Long time kinetic processes usually involve material transport by diffusion. The corresponding microstructural evolution of materials can be analyzed by kinetic Monte Carlo simulation methods, which

  11. First-principles study of defect formation in the photovoltaic semiconductors Cu2GeS3 and Cu2ZnGeS4 for comparison with Cu2SnS3, Cu2ZnSnS4, and CuInSe2

    Science.gov (United States)

    Nishihara, Hironori; Maeda, Tsuyoshi; Shigemi, Akio; Wada, Takahiro

    2017-04-01

    The formation energies of neutral Cu, Ge, and S vacancies in monoclinic Cu2GeS3 and those of neutral Cu, Zn, Ge, and S vacancies in kesterite-type Cu2ZnGeS4 were evaluated by first-principles pseudopotential calculations using plane-wave basis functions. The calculations were performed at typical points in a schematic ternary phase diagram of a Cu-Ge-S system for Cu2GeS3 and in Cu-(Zn1/2Ge1/2)-S and Cu29S16-ZnS-GeS2 pseudoternary phase diagrams for Cu2ZnGeS4. The results have been compared with those for Cu2SnS3, Cu2ZnSnS4, and CuInSe2 calculated with the same version of the CASTEP program code. The results indicate that Cu vacancies are easily formed in Cu2GeS3 and Cu2ZnGeS4 under the Cu-poor condition as in the cases of Cu2SnS3, Cu2ZnSnS4, and CuInSe2, suggesting that Cu2GeS3 and Cu2ZnGeS4 are also preferable p-type absorber materials for thin-film solar cells. Desirable preparation conditions of these thin films for photovoltaic application are discussed using the calculated formation energies of antisite defects.

  12. Conhecimento e interesse em economia

    Directory of Open Access Journals (Sweden)

    João Antonio de Paula

    2003-09-01

    Full Text Available O artigo argumenta em favor da necessidade de preservar o pluralismo em economia. Discute: i a natureza do conhecimento e de sua produção; ii as especificidades da produção do conhecimento em economia e os condicionamentos histórico-culturais do conhecimento; iii as implicações da hegemonia de certa concepção de método em economia.The article argues the need to preserve the pluralism in economics. The article examines: i the nature of the knowledge and of its production; ii the specificity of the knowledge production in economics and the historical and cultural conditionings of the knowledge; iii the implications of the hegemony of a certain methodological conception in economics.

  13. Novel CuCr2O4 embedded CuO nanocomposites for efficient photodegradation of organic dyes

    Science.gov (United States)

    Mageshwari, K.; Sathyamoorthy, R.; Lee, Jeong Yong; Park, Jinsub

    2015-10-01

    Novel photocatalyst based on CuO-CuCr2O4 nanocomposites was synthesized for different Cr3+ concentration by reflux condensation method, and their photocatalytic activity was evaluated by monitoring the photodegradation of methyl orange (MO) and methylene blue dyes (MB) under UV light irradiation. Phase evolution by X-ray diffraction showed monoclinic CuO and tetragonal CuCr2O4 as the components of the prepared nanocomposites. Morphological analysis by scanning electron microscope and transmission electron microscope revealed that the incorporation of Cr3+ in CuO lattice alters the morphology of CuO from microsphere to cluster shape. Photoluminescence spectra of CuO-CuCr2O4 nanocomposites exhibited reduced PL emissions compared to pure CuO, indicating the low recombination rate of photogenerated electrons and holes. As expected, the CuCr2O4 loaded CuO showed enhanced photocatalytic activity for MO and MB dyes, and the kinetic studies suggest that the degradation follows pseudo-first-order kinetics. The enhanced photocatalytic activity of CuO-CuCr2O4 nanocomposites can be attributed to the presence of CuCr2O4 as an electron acceptor, which improves the effective charge separation in CuO.

  14. One-pot synthesis of hierarchical Cu2O/Cu hollow microspheres with enhanced visible-light photocatalytic activity

    Science.gov (United States)

    Hong, Tianjie; Tao, Feifei; Lin, Jiudong; Ding, Wei; Lan, Mingxuan

    2015-08-01

    The hierarchical Cu2O/Cu hollow microspheres have been fabricated by the one-pot solvothermal redox method, which is one-step approach without any surfactant and template. By using the HRTEM, XRD, XPS and UV-vis spectroscopy, the as-prepared product is composed of Cu2O and Cu with energy band gap of 1.72 eV. Based on the time-dependent experiments, the content of Cu2O and Cu compositions can be effectively controlled by adjusting the reaction time and a possible mechanism is proposed. In addition, using various dye molecules to stimulate pollutants, the hierarchical Cu2O/Cu hollow microspheres reacted for 8 h exhibit excellent visible-light photocatalytic activities, which is much higher than those of the Cu2O/Cu catalysts formed at the shorter reaction time, commercial Cu2O powder and the mixture of alone Cu2O and Cu. This enhanced photocatalytic performance makes these hierarchical Cu2O/Cu hollow microspheres a kind of efficient visible-light photocatalyst in removing some organic compounds in wastewater.

  15. BIODISPONIBILIDADE DE METAIS TÓXICOS EM SEDIMENTOS DO RIO SUBAÉ, BAHIA, BRASIL

    Directory of Open Access Journals (Sweden)

    Jucelino Balbino da Silva Júnior

    2016-12-01

    Full Text Available Este trabalho avaliou a biodisponibilidade dos metais Pb, Cd, Zn, Cu e Ni, empregando a técnica dos sulfetos voláteis em ácido (AVS e metais simultaneamente extraídos (SEM, contemplando período chuvoso e de estiagem. As amostras de sedimento foram coletadas em 10 (dez estações ao longo da bacia do rio Subaé, desde a sua nascente até a foz na Baía de Todos os Santos (BTS. Os metais liberados durante a extração foram analisados usando espectrometria de fluorescência de raios-X (TXRF e espectrometria de absorção atômica com otimização eletrotérmica em forno de grafite (GFAAS, e os sulfetos voláteis foram quantificados utilizando potenciometria com eletrodo de íon seletivo (IES. A partir dos resultados obtidos, pode-se concluir, em função dos valores encontrados para os sulfetos e da matéria orgânica, que as concentrações de metais apresentaram valores que caracterizam a possibilidade de efeitos biológicos adversos para a biota nas regiões de baixa salinidade, em ambos os períodos.

  16. On Cu(II) Cu(II) distance measurements using pulsed electron electron double resonance

    Science.gov (United States)

    Yang, Zhongyu; Becker, James; Saxena, Sunil

    2007-10-01

    The effects of orientational selectivity on the 4-pulse electron electron double resonance (PELDOR) ESR spectra of coupled Cu(II)-Cu(II) spins are presented. The data were collected at four magnetic fields on a poly-proline peptide containing two Cu(II) centers. The Cu(II)-PELDOR spectra of this peptide do not change appreciably with magnetic field at X-band. The data were analyzed by adapting the theory of Maryasov, Tsvetkov, and Raap [A.G. Maryasov, Y.D. Tsvetkov, J. Raap, Weakly coupled radical pairs in solids:ELDOR in ESE structure studies, Appl. Magn. Reson. 14 (1998) 101-113]. Simulations indicate that orientational effects are important for Cu(II)-PELDOR. Based on simulations, the field-independence of the PELDOR data for this peptide is likely due to two effects. First, for this peptide, the Cu(II) g-tensor(s) are in a very specific orientation with respect to the interspin vector. Second, the flexibility of the peptide washes out the orientation effects. These effects reduce the suitability of the poly-proline based peptide as a good model system to experimentally probe orientational effects in such experiments. An average Cu(II)-Cu(II) distance of 2.1-2.2 nm was determined, which is consistent with earlier double quantum coherence ESR results.

  17. Synthesis and photocatalytic activity of carbon spheres loaded Cu{sub 2}O/Cu composites

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yinhui, E-mail: lillian09281@hotmail.com; Zhao, Mengyao; Zhang, Na; Li, Ruijuan; Chen, Jianxin

    2015-09-15

    Highlights: • Carbon spheres loaded Cu{sub 2}O/Cu composites are obtained by hydrothermal process. • Cu{sub 2}O/Cu nanocrystals grow on the surface of carbon spheres. • The composites with core–shell structure show highly photo-catalytic activity. • The composites can degrade methyl orange under simulated solar light irradiation. • The composites can be used to treat dye wastewater or organic pollutants. - Abstract: In this work, using amylose as carbon source and cupric acetate as copper source, carbon spheres loaded Cu{sub 2}O/Cu composites were obtained by hydrothermal synthesis. The effects of the molar ratios between glucose and Cu(II), and hydrothermal time on the morphology and sizes of the composites were investigated. The result of photocatalytic experiments demonstrated that the composites could degrade methyl orange in aqueous solution under simulated solar light irradiation. The highest degradation rate was achieved to 93.83% when the composites were prepared by hydrothermal synthesis at 180 °C for 16 h and the molar ratio between glucose and Cu(II) was 10/1. The composites, as new and promising materials, can be used to treat dye wastewater or other organic pollutants.

  18. Carbon Supported Oxide-Rich Pd-Cu Bimetallic Electrocatalysts for Ethanol Electrooxidation in Alkaline Media Enhanced by Cu/CuOx

    Directory of Open Access Journals (Sweden)

    Zengfeng Guo

    2016-04-01

    Full Text Available Different proportions of oxide-rich PdCu/C nanoparticle catalysts were prepared by the NaBH4 reduction method, and their compositions were tuned by the molar ratios of the metal precursors. Among them, oxide-rich Pd0.9Cu0.1/C (Pd:Cu = 9:1, metal atomic ratio exhibits the highest electrocatalytic activity for ethanol oxidation reaction (EOR in alkaline media. X-ray photoelectron spectroscopy (XPS and high resolution transmission electron microscopy (HRTEM confirmed the existence of both Cu and CuOx in the as-prepared Pd0.9Cu0.1/C. About 74% of the Cu atoms are in their oxide form (CuO or Cu2O. Besides the synergistic effect of Cu, CuOx existed in the Pd-Cu bimetallic nanoparticles works as a promoter for the EOR. The decreased Pd 3d electron density disclosed by XPS is ascribed to the formation of CuOx and the spill-over of oxygen-containing species from CuOx to Pd. The low Pd 3d electron density will decrease the adsorption of CH3COads intermediates. As a result, the electrocatalytic activity is enhanced. The onset potential of oxide-rich Pd0.9Cu0.1/C is negative shifted 150 mV compared to Pd/C. The oxide-rich Pd0.9Cu0.1/C also exhibited high stability, which indicated that it is a candidate for the anode of direct ethanol fuel cells (DEFCs.

  19. Induction Coilgun for EM Mortar

    Science.gov (United States)

    2007-06-01

    Agency is investigating electromagnetic (EM) guns for the next generation combat vehicle providing improved performance and survivability without the...use of propellant. The two-year program was initiated in 2005 to design a coilgun and a railgun to launch an existing mortar round with an EM...through a structural frame. Capacitor bank modules currently in fabrication and test utilize 1980’s technology capacitors , but new ideas in

  20. Chemical Composition<em> em>of Hexane Extract of <em>Citrus aurantifoliaem> and<em> em>Anti->Mycobacterium tuberculosisem> Activity of Some of Its Constituents

    Directory of Open Access Journals (Sweden)

    María del Rayo Camacho-Corona

    2012-09-01

    Full Text Available The main aim of this study was to isolate and characterize the active compounds from the hexane extract of the fruit peels of <em>Citrus aurantiifoliaem>, which showed activity against one sensitive and three monoresistant (isoniazid, streptomycin or ethambutol strains of <em>Mycobacterium tuberculosis em>H37Rv. The active extract was fractionated by column chromatography, yielding the following major compounds: 5-geranyloxypsoralen (1; 5-geranyloxy-7-methoxycoumarin (2; 5,7-dimethoxycoumarin (3; 5-methoxypsoralen (4; and 5,8-dimethoxypsoralen (5. The structures of these compounds were elucidated by 1D and 2D NMR spectroscopy. In addition, GC-MS analysis of the hexane extract allowed the identification of 44 volatile compounds, being 5,7-dimethoxycoumarin (15.79%, 3-methyl-1,2-cyclopentanedione (8.27%, 1-methoxy-ciclohexene (8.0%, corylone (6.93%, palmitic acid (6.89%, 5,8-dimethoxypsoralen (6.08%, a-terpineol (5.97%, and umbelliferone (4.36%, the major constituents. Four isolated coumarins and 16 commercial compounds identified by GC-MS were tested against <em>M. tuberculosisem> H37Rv and three multidrug-resistant <em>M. tuberculosisem> strains using the Microplate Alamar Blue Assay. The constituents that showed activity against all strains were 5 (MICs = 25–50 mg/mL, 1 (MICs = 50–100 mg/mL, palmitic acid (MICs = 25–50 mg/mL, linoleic acid (MICs = 50–100 mg/mL, oleic acid (MICs = 100 mg/mL, 4-hexen-3-one (MICs = 50–100 mg/mL, and citral (MICs = 50–100 mg/mL. Compound 5 and palmitic acid were the most active ones. The antimycobacterial activity of the hexane extract of <em>C. aurantifoliaem> could be attributed to these compounds.

  1. Two New Compounds Isolated from<em> Liriope muscariem>

    Directory of Open Access Journals (Sweden)

    Rui-Chao Lin

    2012-07-01

    Full Text Available Two new compounds, (2<em>S>,3<em>R>-methyl 7-hydroxy-2-(4-hydroxy-3-methoxy-phenyl-3-(hydroxymethyl-2,3-dihydrobenzofuran-5-carboxylate (1 and (4<em>R,>5<em>S>-5-(3-hydroxy-2,6-dimethylphenyl-4-isopropyldihydrofuran-2-one (2, tentatively named norcurlignan and limlactone, respectively, were isolated from <em>Liriope muscariem>, together with the known compound (−-pinoresinol (3. The structures of these compounds were elucidated and characterized on the basis of 1D NMR, 2D NMR, CD and MS data. The <em>in vitroem> antioxidant activities of compounds 13 were assessed by the DPPH and ABTS scavenging methods.

  2. Molecular switching analyzed with sub-molecular precision: CuPc on Cu(111)

    Energy Technology Data Exchange (ETDEWEB)

    Schaffert, Johannes; Cottin, Maren; Sonntag, Andreas; Karacuban, Hatice; Bobisch, Christian; Moeller, Rolf [Faculty of Physics, Center for Nanointegration Duisburg-Essen, University of Duisburg-Essen, 47048 Duisburg (Germany); Lorente, Nicolas [Centro de Investigacion en Nanociencia y Nanotecnologia, Campus de la Universitat Autonoma de Barcelona, 08193 Bellaterra (Spain)

    2011-07-01

    The current fluctuations in Scanning Tunneling Microscopy and Spectroscopy have been analyzed in real time using special analogue electronics. This type of Scanning Action Microscopy technique allows to map topography and switching processes simultaneously. For the Cu-Phthalocyanine (CuPc) molecule on Cu(111), switching between two states is observed. The switching frequency, the switching amplitude and the ratio between the residence times in the observed states can be studied with Angstrom spacial resolution. Spectroscopic data obtained at 7 K yields information about the involved electronic states. Based on the experimental data as well as DFT calculations a model is presented. The CuPc molecule switches between different adsorption configurations, which are attributed to different angles of molecular rotation on the Cu(111) surface.

  3. Study of the /sup 63/Cu(n,. gamma. )/sup 64/Cu reaction

    Energy Technology Data Exchange (ETDEWEB)

    Delfini, M.G.; Kopecky, J.; de Haas, J.B.M.; Liou, H.I.; Chrien, R.E.; Endt, P.M.

    1983-08-08

    The ..gamma..-radiation resulting from the capture of unpolarized thermal, 2 and 24 keV neutrons in enriched /sup 63/Cu, and of polarized thermal neutrons in /sup 63/Cu oriented at low temperature has been investigated. Of the 323 ..gamma..-rays observed 299 could be placed in a /sup 64/Cu level scheme containing 109 levels. The reaction Q-value amounts to 7916.09(12) keV. The Z/sup 2/ analysis of the ..gamma..-ray angular distributions obtained from capture of polarized neutrons in oriented /sup 63/Cu resulted in three unambiguous spin assignments for levels in /sup 64/Cu. The fraction of the Jsup(..pi..) = 1/sup -/ channel in the thermal capture was determined as (94 +- 2)%. For one level an unambiguous spin assignment has been obtained from the decay scheme.

  4. Sobrevivência de Bradyrhizobium e Azorhizobium em misturas de solo contaminadas com metais pesados

    Directory of Open Access Journals (Sweden)

    A. Matsuda

    2002-03-01

    Full Text Available Estudos foram realizados no Departamento de Ciência do Solo da Universidade Federal de Lavras (MG, no período de novembro/1999 a janeiro/2000, com o objetivo de avaliar a sobrevivência de estirpe e isolados de rizóbio em solo contaminado com metais pesados e verificar a relação entre tolerância do rizóbio a metais pesados em meio de cultura e sua sobrevivência em solo contaminado. Foram utilizados os dois microrganismos mais tolerantes [BR-4406 (estirpe recomendada para Enterolobium spp. e UFLA-01-457 (isolado de solo contaminado, ambos pertencentes ao gênero Bradyrhizobium ] e os dois mais sensíveis (UFLA-01-486 e UFLA-01-510, isolados de solo contaminado, pertencentes ao gênero Azorhizobium , todos selecionados de um grupo de 60estirpes/isolados em estudos prévios deste laboratório, em meio de cultura suplementado com metais pesados.Empregaram-se misturas de um Latossolo Vermelho-Escuro (LE que continham 0, 15 e 45% (v/v de um Latossolo Vermelho-Amarelo plíntico contaminado com Zn, Cd, Pb e Cu. As misturas de solo contaminado foram inoculadas com 20mL de cultura em YM na fase log das estirpes mencionadas, as quais foram testadas separadamente com três repetições. A avaliação do número de células viáveis no solo, realizada aos 0, 7, 14, 21 e 28dias de incubação, pelo método das diluições sucessivas e inoculação em placas com meio YMA, revelou comportamento diferenciado entre os organismos estudados. O número médio de células que sobreviveram ao final de 28 dias de incubação foi de (em UFCg-1de solo: 10(10,36, 10(10,29 e 10(9,70, para Bradyrhizobium, e 10(9,36, 10(7,54 e 0, para Azorhizobium em misturas de 0, 15 e 45% de solo contaminado, respectivamente. Portanto, houve maior sobrevivência de Bradyrhizobium do que de Azorhizobium , indicando maior tolerância a metais pesados do primeiro gênero.Como Bradyrhizobium foi também mais tolerante "in vitro", os resultados indicam haver relação entre o

  5. Antioxidant Activity of Various Parts of <em>Cinnamomum> cassiaem> Extracted with Different Extraction Methods

    Directory of Open Access Journals (Sweden)

    Li-Yeh Chuang

    2012-06-01

    Full Text Available The aim of this study was to investigate the antioxidant activities of various parts (barks, buds, and leaves of <em>Cinnamomum cassia em>extracted with ethanol and supercritical fluid extraction (SFE. For the antioxidant activity comparison, IC50 values of the SFE and ethanol extracts in the DPPH scavenging assay were 0.562–10.090 mg/mL and 0.072–0.208 mg/mL, and the Trolox equivalent antioxidant capacity (TEAC values were 6.789–58.335 mmole Trolox/g and 133.039–335.779 mmole Trolox/g, respectively. In addition, the total flavonoid contents were 0.031–1.916 g/ 100 g dry weight of materials (DW and 2.030–3.348 g/ 100 g DW, and the total phenolic contents were 0.151–2.018 g/ 100 g DW and 6.313–9.534 g/ 100 g DW in the SFE and ethanol extracts, respectively. Based on the results, the ethanol extracts of <em>Cinnamon> barks have potential value as an antioxidant substitute and this study also provide a better technique to extract the natural antioxidant substances from <em>C. cassiaem>.

  6. 界面耦合作用对Cu(Ni)/Sn-Ag-Cu/Cu(Ni)BGA 焊点界面IMC形成与演化的影响%EFFECT OF THE CROSS-INTERACTION ON THE FORMATION AND EVOLUTION OF INTERMETALLIC COMPOUNDS IN Cu(Ni)/Sn-Ag-Cu/Cu(Ni) BGA STRUCTURE SOLDER JOINTS

    Institute of Scientific and Technical Information of China (English)

    李勋平; 周敏波; 夏建民; 马骁; 张新平

    2011-01-01

    研究了焊盘材料界面耦合作用对Cu(Ni)/Sn-3.0Ag-0.5Cu/Cu(Ni)BGA(Ball Grid Array)结构焊点焊后态和125℃等温时效过程中界面金属间化合物(IMC)的成分、形貌和生长动力学的影响.结果表明,凸点下金属层(UBM)Ni界面IMC的成分与钎料中Cu含量有关,钎料中Cu含量较高时界面IMC为(Cu,Ni)6Sn5,而Cu含量较低时,则生成(Cu,Ni)3Sn4;Cu-Ni耦合易导致Cu/Sn-3.0Ag-0.5Cu/Ni焊点中钎料/Ni界面IMC异常生长并产生剥离而进入钎料.125℃等温时效过程中,Sn-3.0Ag-0.5Cu/Cu界面IMC的生长速率常数随钎料中Cu含量增加而提高,Cu-Cu耦合降低一次回流侧IMC生长速率常数;Cu-Ni耦合和Ni-Ni耦合均导致焊点一次回流Ni侧界面IMC的生长速率常数增大,但Ni对界面IMC生长动力学的影响大于Cu;Ni有利于抑制Cu界面Cu3Sn生长,降低界面IMC生长速率,但Cu-Ni耦合对Cu界面Cu3Sn中Kirkendall空洞率无明显影响.%The formation and evolution of interfacial intermetallic compounds (IMCs) in Cu(Ni)/Sn-3.0Ag-0.5Cu/Cu(Ni) BGA (Ball Grid Array) structure solder joints both in the asreflowed state and undergoing isothermal aging at 125 C were investigated. The results show that there exists a significant cross-interaction effect of the solder pad/under bump metal (UBM) on the composition, morphology and growth kinetics of interfacial IMCs in solder joints. The reactions of solder/Ni UBM strongly depends on the Cu content of the solder, for a high Cu content, a continuous (Cu, Ni)6Sn5 layer forms at the interface, while for a low Cu content, a continuous (Ni, Cu)3Sn4 layer appears at the interface. The cross-interaction of Cu and Ni in Cu/Sn-3.0Ag-0.5Cu(SAC)/Ni solder joints has obvious influence on the composition and morphology of the interfacial IMC; and the IMC spalling phenomenon occurs at the interface of Ni side. During isothermal aging at 125 ℃, the growth rate constant of the interfacial IMC layer in SAC/Cu and Cu/SAC/Cu joints increases with

  7. Regional Suppression of <em>Bactrocera> Fruit Flies (Diptera: Tephritidae in the Pacific through Biological Control and Prospects for Future Introductions into Other Areas of the World

    Directory of Open Access Journals (Sweden)

    Roger I. Vargas

    2012-08-01

    Full Text Available <em>Bactrocera> fruit fly species are economically important throughout the Pacific. The USDA, ARS U.S. Pacific Basin Agricultural Research Center has been a world leader in promoting biological control of <em>Bactrocera> spp. that includes classical, augmentative, conservation and IPM approaches. In Hawaii, establishment of <em>Bactrocera> <em>cucurbitae> (Coquillett in 1895 resulted in the introduction of the most successful parasitoid, <em>Psyttalia> <em>fletcheri> (Silvestri; similarly, establishment of <em>Bactrocera> <em>dorsalis> (Hendel in 1945 resulted in the introduction of 32 natural enemies of which <em>Fopius> <em>arisanus> (Sonan, <em>Diachasmimorpha> <em>longicaudata> (Ashmead and <em>Fopius> <em>vandenboschi> (Fullaway were most successful. Hawaii has also been a source of parasitoids for fruit fly control throughout the Pacific region including Australia, Pacific Island Nations, Central and South America, not only for <em>Bactrocera> spp. but also for <em>Ceratitis> and <em>Anastrepha> spp. Most recently, in 2002, <em>F.> <em>arisanus> was introduced into French Polynesia where <em>B.> <em>dorsalis> had invaded in 1996. Establishment of <em>D.> <em>longicaudata> into the new world has been important to augmentative biological control releases against <em>Anastrepha> spp. With the rapid expansion of airline travel and global trade there has been an alarming spread of <em>Bactrocera> spp. into new areas of the world (<em>i.e.>, South America and Africa. Results of studies in Hawaii and French Polynesia, support parasitoid introductions into South America and Africa, where <em>B.> <em>carambolae> and <em>B.> <em>invadens>, respectively, have become established. In addition, <em>P.> <em>fletcheri> is a candidate for biological control of <em>B.> <em>cucurbitae> in Africa. We review past and more

  8. Investigation on the Microstructure, Interfacial IMC Layer, and Mechanical Properties of Cu/Sn-0.7Cu- xNi/Cu Solder Joints

    Science.gov (United States)

    Yang, Li; Ge, Jinguo; Zhang, Yaocheng; Dai, Jun; Liu, Haixiang; Xiang, Jicen

    2016-07-01

    Sn-0.7Cu- xNi composite solder has been fabricated via mechanical mixing of different weight percentages of Ni particles with Sn-0.7Cu solder paste, and the effect of the Ni concentration on the microstructure, wettability, and tensile properties of Cu/Sn-0.7Cu- xNi/Cu solder joints investigated. The results show that refined dot-shaped particles of intermetallic compounds (IMCs) are uniformly dispersed in a primary β-Sn matrix in the Cu/Sn-0.7Cu-(0.05-0.1)Ni/Cu solder joints. The interfacial IMC layer thickness increased slightly when adding Ni content to 0.05 wt.%, then rapidly when further increasing the Ni concentration to 0.4 wt.%. Excellent wettability with bright appearance was obtained for the Sn-0.7Cu-0.05Ni solder due to diminished interfacial tension. The tensile properties improved after adding Ni content to 0.05 wt.% due to the presence of the refined dot-like IMC particles, in agreement with theoretical predictions based on the combination of dispersion and grain-refinement strengthening mechanisms. Refined microstructure and enhanced mechanical properties were obtained for the Cu/Sn-0.7Cu-0.05Ni/Cu solder joint.

  9. Deficiências minerais em vacas em lactação da bacia leiteira do município de Rondon do Pará, estado do Pará

    Directory of Open Access Journals (Sweden)

    Henrique A. Bomjardim

    2015-05-01

    Full Text Available ResumoRealizou-se um estudo das deficiências minerais em vacas em lactação de rebanhos leiteiros pertencentes a 13 propriedades da bacia leiteira do município de Rondon do Pará, estado do Pará. Foram determinados os níveis de fósforo (P no osso, e os níveis de cobre (Cu, cobalto (Co, selênio (Se e zinco (Zn no fígado de 47 vacas leiteiras no 2º terço da lactação. Estas amostras foram coletadas por meio de biópsias realizadas no terço superior da 12a costela do lado direito e no bordo caudal do lobo caudado do fígado, respectivamente. Os rebanhos eram formados por animais mestiços (Holandes x Zebu, mantidos em sistema de produção extensivo em pastos de Brachiaria brizantha cv Marandu e recebiam suplementação mineral. A mistura mineral em 12 propriedades era do tipo comercial, dita "completa", acrescida de quantidades de NaCl acima do recomendado pelos fabricantes em dez propriedades. Em sete propriedades as misturas minerais eram fornecidas em cochos sem cobertura e em oito, o fornecimento da mistura mineral não era realizado diariamente. Em 11 propriedades, havia históricos clínicos condizentes com deficiências minerais nos rebanhos. Nessas fazendas a retenção de placenta e a osteofagia foram as alterações mais relatadas. Após as análises minerais observou-se deficiência de P em cinco propriedades, de Co em três propriedades, de Se em nove propriedades e de Zn em dez propriedades. Conclui-se que ocorre a deficiência de P, Co, Se e Zn; a suplementação mineral realizada na maioria das propriedades não atendeu as exigências diárias de P, Se e Co, baseadas no consumo estimado de 30 g de NaCl/animal/dia; os cochos pouco adequados ou inadequados para a suplementação, assim como o fornecimento inconstante das misturas minerais possivelmente contribuíram para a deficiência de um ou mais minerais.

  10. The Effect of Composition of Different Ecotoxicological Test Media on Free and Bioavailable Copper from CuSO4 and CuO Nanoparticles: Comparative Evidence from a Cu-Selective Electrode and a Cu-Biosensor

    Directory of Open Access Journals (Sweden)

    Angela Ivask

    2011-11-01

    Full Text Available The analysis of (bioavailable copper in complex environmental settings, including biological test media, is a challenging task. In this study, we demonstrated the potential of a recombinant Pseudomonas fluorescens-based biosensor for bioavailability analysis of CuSO4 and CuO nanoparticles (nano-CuO in seventeen different ecotoxicological and microbiologial test media. In parallel, free Cu in these test media was analysed using Cu-ion selective electrode (Cu-ISE. In the case of CuSO4, both free and bioavailable Cu decreased greatly with increasing concentration of organics and phosphates in the tested media. A good correlation between free and bioavailable Cu was observed (r = 0.854, p < 0.01 indicating that the free Cu content in biological test media may be a reasonably good predictor for the toxicity of CuSO4. As a proof, it was demonstrated that when eleven EC50 values for CuSO4 from different organisms in different test media were normalized for the free Cu in these media, the difference in these EC50 values was decreased from 4 to 1.8 orders of magnitude. Thus, toxicity of CuSO4 to these organisms was attributed to the properties of the test media rather than to inherent differences in sensitivity between the test organisms. Differently from CuSO4, the amount of free and bioavailable Cu in nano-CuO spiked media was not significantly correlated with the concentration of organics in the test media. Thus, the speciation of nano-CuO in toxicological test systems was not only determined by the complexation of Cu ions but also by differential dissolution of nano-CuO in different test conditions leading to a new speciation equilibrium. In addition, a substantial fraction of nano-CuO that was not detectable by Cu-ISE (i.e., not present as free Cu-ions was bioavailable to Cu-biosensor bacteria. Thus, in environmental hazard analysis of (nano particulate materials, biosensor analysis may be more informative than other analytical techniques. Our

  11. Transient terminal Cu-nitrene intermediates from discrete dicopper nitrenes.

    Science.gov (United States)

    Badiei, Yosra M; Krishnaswamy, Ammani; Melzer, Marie M; Warren, Timothy H

    2006-11-29

    Reaction of the copper(I) beta-diketiminate {[Me3NN]Cu}2(mu-toluene) with the aryl azide N3Ar (Ar = 3,5-Me2C6H3) in toluene results in immediate effervescence and formation of the dicopper nitrene {[Me3NN]Cu}2(mu-NAr) (2) in 77% yield. The X-ray structure of 2 shows nearly symmetric bonding of the nitrene to two Cu centers separated by 2.911(1) A with Cu-N distances of 1.794(5) and 1.808(5) A along with a Cu-N-Cu angle of 107.8(2) degrees . This structure is conceptually related to the dicopper carbenes {[MexNN]Cu}2(mu-CPh2) (x = 2 or 3) (Dai, X.; Warren J. Am. Chem. Soc. 2004, 126, 10085. Badiei, Y. M.; Warren J. Organomet. Chem. 2005, 690, 5989.) which exhibit shorter Cu-Cu distances (2.4635(7) or 2.485(1) A) and acute Cu-C-Cu angles (79.51(14) or 80.1(2) degrees ). Addition of the Cu(I) anilidoimine {[Me2AI]Cu}2 (prepared from CuOtBu and the aniline-imine H[Me2AI] in 77% yield) to a benzene-d6 solution of 2 results in the formation of two new anilidoimine complexes {[Me2AI]Cu(mu- NAr)Cu[Me3NN] (5) and {[Me2AI]Cu}2(mu-NAr) (6) as well as [Me3NN]Cu(benzene) over 3 h. These observations are consistent with the slow dissociation of a [Me3NN]Cu fragment from 2 to generate the transient terminal nitrenes [Me3NN]Cu=NAr and [Me2AI]Cu=NAr quickly trapped by the [Me2AI]Cu fragment to form the new unsymmetrical and symmetrical dicopper nitrenes 5 and 6. Preliminary reactivity studies indicate electrophilic reactivity at the nitrene moiety. Dicopper nitrene 2 reacts with 10 equiv PMe3 and CNtBu to give ArN=PMe3 and ArN=C=NtBu in 94% and 92% yields, respectively, with concomitant formation of [Me3NN]Cu(L) (L = PMe3 and CNtBu). Reaction between 2 and 2 equiv PMe3 allows for observation of the structurally characterized Cu(I) phosphaimide [Me3NN]Cu(ArN=PMe3) (7).

  12. Properties of electrodeposited CoFe/Cu multilayers: The effect of Cu layer thickness

    Energy Technology Data Exchange (ETDEWEB)

    Sahin, Turgut, E-mail: stsahin4@hotmail.com [Deparment of Physics, Science and Literature Faculty, Balikesir University, 10100 Balikesir (Turkey); Kockar, Hakan, E-mail: hkockar@balikesir.edu.tr [Deparment of Physics, Science and Literature Faculty, Balikesir University, 10100 Balikesir (Turkey); Alper, Mursel, E-mail: malper@uludag.edu.tr [Deparment of Physics, Science and Literature Faculty, Uludag University, 16059 Gorukle, Bursa (Turkey)

    2015-01-01

    CoFe/Cu multilayers were potentiostatically electrodeposited on Ti substrates as a function of different non-magnetic (Cu) layer thicknesses, and their characterizations were investigated. The compositional analysis performed by energy dispersive X-ray spectroscopy disclosed that the Cu content in the multilayers increased and the Co content decreased as non-magnetic layer was increased. However, the Fe content was almost stable. The scanning electron microscopy studies showed that the surface morphology of the films is strongly affected by the non-magnetic layer thickness, and X-ray diffraction was used to analyse the structural properties of the multilayers and revealed that the multilayers have face-centred cubic (fcc) structure and their preferred orientations change depending on the Cu layer thickness. In the case of magnetoresistance measurements of the multilayers performed at room temperature, the highest giant magnetoresistance (GMR) values exhibited for the films with the Cu layer thickness (6.0 nm) whereas the lowest GMR magnitudes were observed for the films without Cu layer. Therefore, the variations of the Cu layer thicknesses were observed to have a significant effect on the GMR of multilayers. The differences observed in the magnetotransport properties were attributed to the microstructural changes caused by the Cu layer thickness. - Highlights: • CoFe/Cu multilayers were potentiostatically electrodeposited on Ti substrates. • Microstructural and magnetoresistance properties of CoFe/Cu multilayers were investigated. • All films had a face-centred cubic structure irrespective of the multilayer content. • All samples exhibited GMR and the maximum GMR value was 11%.

  13. WETTING OF COPPER BY LEAD-FREE Sn-Cu SOLDERS AND SHEAR STRENGTH OF CuCu JOINTS

    Directory of Open Access Journals (Sweden)

    Pavol Šebo

    2009-04-01

    Full Text Available Developing and microstructure of lead-free Sn-Cu solders containing 3, 5 and 10 wt. % of copper in bulk as well as in ribbon form is presented. Wetting of copper substrate by these solders at the temperatures 300, 350 and 400°C in air (partially in N2+10H2 during 1800 s was studied by sessile drop method. Joints Cu – solder – Cu were prepared at 300°C and 1800 s in air as well as in gas mix and their shear strength was measured. The microstructure was studied by light and scanning electron microscopy (SEM equipped with energy dispersive X-ray analyzer and standard X-ray diffraction machine. Wetting angle decreases with increasing wetting temperature. Wetting angle increased for higher (10 wt. % amount of copper in solder. Shear strength of the joints decreases with increasing the copper concentration in solder.

  14. Investigação eletroquímica e espestroscópica da Polianilina em solução aquosa de Nitrato de cobre

    OpenAIRE

    2002-01-01

    O objetivo desse trabalho foi caracterizar a interação dos íons Cu+ e/ou Cu2+ com a polianilina que ocorre durante a voltametria cíclica de um filme de polianilina em uma solução de nitrato de cobre. A técnica de voltametria cíclica foi utilizada para fazer uma análise inicial dos processos redox atribuídos à interação dos íons Cu+ e/ou Cu2+ com a polianilina. Nesses experimentos observou-se a influência da espessura do filme de polianilina sintetizado com cargas entre 180 e 1800 μC, ...

  15. Binuclear Cu(A) Formation in Biosynthetic Models of Cu(A) in Azurin Proceeds via a Novel Cu(Cys)2His Mononuclear Copper Intermediate.

    Science.gov (United States)

    Chakraborty, Saumen; Polen, Michael J; Chacón, Kelly N; Wilson, Tiffany D; Yu, Yang; Reed, Julian; Nilges, Mark J; Blackburn, Ninian J; Lu, Yi

    2015-10-06

    Cu(A) is a binuclear electron transfer (ET) center found in cytochrome c oxidases (CcOs), nitrous oxide reductases (N₂ORs), and nitric oxide reductase (NOR). In these proteins, the Cu(A) centers facilitate efficient ET (kET > 10⁴s⁻¹) under low thermodynamic driving forces (10-90 mV). While the structure and functional properties of Cu(A) are well understood, a detailed mechanism of the incorporation of copper into the protein and the identity of the intermediates formed during the Cu(A) maturation process are still lacking. Previous studies of the Cu(A) assembly mechanism in vitro using a biosynthetic model Cu(A) center in azurin (Cu(A)Az) identified a novel intermediate X (Ix) during reconstitution of the binuclear site. However, because of the instability of Ix and the coexistence of other Cu centers, such as Cu(A)' and type 1 copper centers, the identity of this intermediate could not be established. Here, we report the mechanism of Cu(A) assembly using variants of Glu114XCuAAz (X = Gly, Ala, Leu, or Gln), the backbone carbonyl of which acts as a ligand to the Cu(A) site, with a major focus on characterization of the novel intermediate Ix. We show that Cu(A) assembly in these variants proceeds through several types of Cu centers, such as mononuclear red type 2 Cu, the novel intermediate Ix, and blue type 1 Cu. Our results show that the backbone flexibility of the Glu114 residue is an important factor in determining the rates of T2Cu → Ix formation, suggesting that Cu(A) formation is facilitated by swinging of the ligand loop, which internalizes the T2Cu capture complex to the protein interior. The kinetic data further suggest that the nature of the Glu114 side chain influences the time scales on which these intermediates are formed, the wavelengths of the absorption peaks, and how cleanly one intermediate is converted to another. Through careful understanding of these mechanisms and optimization of the conditions, we have obtained Ix in ∼80

  16. Extração fracionada de metais pesados em latossolo vermelho-amarelo

    Directory of Open Access Journals (Sweden)

    P. C. Gomes

    1997-12-01

    Full Text Available Amostras dos horizontes A e B de um latossolo vermelho-amarelo húmico textura muito argilosa foram incubadas em solução de sais de Cd, Cr, Cu, Ni, Pb e Zn, com os objetivos de adaptar método de extração fracionada de metais e avaliar os seus comportamentos nas formas solúvel, trocável, ligados à matéria orgânica, aos óxidos de Al e Fe e residual do solo. O ensaio foi desenvolvido em casa de vegetação da Universidade Federal de Viçosa, no período de 27 de março a 26 de setembro de 1994. O delineamento experimental foi em blocos ao acaso, em esquema fatorial 2 x 2, com três repetições. Os tratamentos consistiram de dois horizontes e duas doses de metais. Após 17 horas de incubação, as amostras foram secas ao ar, homogeneizadas, passadas em peneira de 2 mm de abertura de malha e guardadas em sacos plásticos para posterior extração dos metais. Em seguida, foram submetidas ao método de extração fracionada, com avaliação do tratamento com NaOH, para caracterizar a forma óxidos de Al. A extração fracionada mostrou-se adequada para estudos do comportamento de metais no solo. O Cd foi encontrado, principalmente, nas formas solúvel e trocável, e o Cr, nas formas químicas mais estáveis, ligado aos óxidos de Fe e residual. O Cu foi o metal que apresentou maior afinidade pelos óxidos de Fe, e o Pb, pela matéria orgânica. O Ni foi encontrado, principalmente, na forma residual e apresentou menor afinidade pela matéria orgânica. O estudo do Zn foi inviabilizado pela contaminação dos extratos guardados em frascos com tampas de borracha. É necessário desenvolver ou adaptar métodos para caracterização de metais associados aos óxidos de Fe e de Al.

  17. Explosive compaction of CuCr alloys

    Institute of Scientific and Technical Information of China (English)

    李金平; 罗守靖; 龚朝晖; 牛玮; 纪松

    2002-01-01

    The production of CuCr alloys utilizing explosive compaction was studied. Mixture powders of CuCr alloys placed in tubes with a dimension of d14.0mm×21.4mm can be compacted using explosive pads of 16.5mm or 22.5mm. Thicker pads of explosive make the compacts more porous. The effects of the ratio of me/mp, ratio of me/(mp+mt) and impact energy on the density of compacts were similar, they were chosen to control explosive compaction, respectively. When adequate value of the parameters me/mp, me/(mt+mp) and impact energy of unit area of tube was chosen, high density(7.858g/cm3), high hardness(HB189) and low conductance (13.6MS/m) of CuCr alloys could be made by explosive compaction. The general properties of CuCr alloys by explosive compaction are similar to those of CuCr alloys by traditional process.

  18. Mechanism for Cu2+ Sorption on Palygorskite

    Institute of Scientific and Technical Information of China (English)

    CHEN Tian-Hu; PENG Shu-Chuan; XU Hui-Fang; SHI Xiao-Li; HUANG Chuan-Hui

    2005-01-01

    A single-factor experiment of copper ion adsorption on pure palygorskite was carried out to understand the Cu2+ sorption of palygorskite-an important clay mineral in soil and sedimentary rock. In addition, pH of the solution and the surface microstructure of palygorskite were investigated before and after adsorption. The experimental results indicated that efficiency of Cu2+ removal was related to the oscillation rate of the specimen shaker, sorption time, initial pH value and the amount of adsorbent added. Palygorskite induced Cu2+ hydrolysis and interaction between copper hydroxide colloids and palygorskite surfaces, as observed with transmission electron microscopy (TEM), were the main contributions to palygorskite removal of Cu2+. This mechanism was different from adsorption at the mineral-water interface. It was proposed that surface hydrolysis of palygorskite raised the alkalinity of the palygorskite-water interface and suspension system. Thus, the induced pH of the solution was then high enough for Cu2+ hydrolysis on the mineral surface and in solution.

  19. Avaliação da necessidade de frio em pessegueiro Avaliation of chilling requirement in peach

    Directory of Open Access Journals (Sweden)

    Idemir Citadin

    2002-12-01

    Full Text Available A necessidade de frio de seis cultivares de pessegueiro [Prunus persica (L. Batsch] foi estudada em plantas de um e dois anos, em vasos, submetidas a 150; 300; 450 e 600 horas a 2ºC, e em ramos coletados periodicamente em plantas sob condições de frio natural, a campo. Considerando os resultados obtidos nos dois experimentos, estima-se que a necessidade de frio de 'Precocinho' é em torno de 300 horas a 2ºC, equivalente a 150 unidades de frio (UF pelo modelo de Utah, ou próxima a 200 horas abaixo de 12ºC; para 'Eldorado' e 'Rio grandense', em 450 horas a 2ºC (225 UF ou 365 horas abaixo de 12ºC; para 'BR-1', em 450 horas a 2ºC (225 UF ou 418 horas abaixo de 12ºC; e para 'Planalto' e 'Della Nona', acima de 600 horas a 2ºC (>300 UF. Não foi possível estabelecer a necessidade de frio abaixo de 12ºC para 'Della Nona'.Chilling requirement was investigated in six peach [Prunus persica (L. Batsch] cultivars observing plants in containers, with one or two years, artificially chilled by 150, 300, 450, and 600 hours at 2ºC, and in excised shoots that were periodically taken from the orchard during the rest period. Chilling requirement of 'Precocinho' is 300 hours at 2ºC (around 150 chilling units - CU - using Utah Model or around 200 hours under 12ºC; 'Riograndense' and 'Eldorado' have 450 chilling hours at 2ºC (225 CU or 365 chilling hours under 12ºC; 'BR-1' is 450 chilling requirement at 2ºC (225 CU or 418 chilling hours under 12 ºC; and 'Planalto' and 'Della Nona' are over 600 chilling hours at 2ºC (>300 CU. It was not possible to estimate chilling requirement in 'Della Nona' using temperatures under 12 ºC.

  20. Métodos de extração para quantificação de cobre disponível em fertilizantes Extraction methods for quantification of available copper in fertilizers

    Directory of Open Access Journals (Sweden)

    Ana Rosa Ribeiro Bastos

    2007-04-01

    Full Text Available Neste estudo, determinou-se a solubilidade do Cu em diferentes fertilizantes e avaliou-se sua correlação com a absorção deste micronutriente por plantas de arroz (Oryza sativa L.. Utilizaram-se as seguintes fontes: mistura de óxido cúprico p.a. e Cu metálico moído p.a.; óxido de Cu 40 Ind.; sulfato de Cu p.a.; minério calcopirita; Cu metal moído p.a. e óxido cúprico p.a. Foram determinados o teor total de Cu e os teores de Cu solúvel em água e em soluções de ácido cítrico a 20 g L-1, de citrato neutro de amônio (1 + 9 e de DTPA 0,005 mol L-1. As solubilidades nesses três últimos extratores foram determinadas por agitação da amostra por uma hora e por fervura durante cinco minutos. Paralelamente, foram realizados experimentos em casa de vegetação, com cultivos sucessivos da cultura do arroz, para verificar os efeitos imediato e residual da aplicação das fontes de Cu em diferentes doses (0; 0,75; 1,5 e 3 mg dm-3 de Cu em um Neossolo Quartzarênico órtico. Os fertilizantes apresentaram solubilidade diferenciada, sendo diferente também com relação ao teor total de Cu. Todas as fontes testadas foram eficientes no fornecimento desse elemento às plantas, embora doses mais elevadas sejam necessárias quando se usam as fontes minério calcopirita e óxido de Cu 40 Ind. As fontes apresentaram efeito residual de Cu no solo após o segundo cultivo das plantas de arroz. Diante das várias fontes com Cu e das diferenças entre elas com relação à solubilidade e eficiência agronômica, sugere-se a adoção de mais um tipo de garantia para o micronutriente além do teor total. O citrato neutro de amônio (1 + 9, na relação 1:100, com fervura por cinco minutos, mostrou-se adequado para determinação do teor de Cu disponível em fertilizantes.In this study available cooper (Cu content in different sources of this micronutrient was determined using several extractants. The cooper sources were: coppper oxide p.a. + copper

  1. CATETERES EM TERAPIA INTENSIVA

    Directory of Open Access Journals (Sweden)

    Carolina de Deus Lisboa

    2014-01-01

    Full Text Available Pesquisa com os objetivos de identificar falhas na administração de medicamentos por sondas e caracterizar a interrupção ou não da nutrição no caso de medicamentos que exigem jejum relativo. Estudo epidemiológico, transversal, observacional, numa terapia intensiva, com amostra de 350 doses administradas por 56 técnicos de enfermagem. Resultados mostraram que não houve pausa entre a administração do medicamento e a infusão de dieta enteral em 116 (33,14% doses de medicamentos que necessitavam de jejum relativo, entre os quais captopril, varfarina sódica, levotiroxina sódica, digoxina e fenitoína sódica. A irrigação das sondas não ocorreu na maioria dos casos (94,28%. Conclui-se que é possível que os medicamentos citados tenham tido sua biodisponibilidade sérica reduzida, comprometendo sua eficácia terapêutica e que a falta da prática de irrigar sondas com água estéril, antes de administrar medicamentos, configura-se como a ausência de um cuidado específico fundamental para evitar a obstrução das mesmas.

  2. Environmentally cued hatching in reptiles.

    Science.gov (United States)

    Doody, J S

    2011-07-01

    Evidence is accumulating for the widespread occurrence of environmentally cued hatching (ECH) in animals, but its diversity and distribution across taxa are unknown. Herein I review three types of ECH in reptiles: early hatching, delayed hatching, and synchronous hatching. ECH is currently known from 43 species, including turtles, crocodilians, lizards, snakes, tuatara, and possibly worm lizards. Early hatching caused by physical disturbance (e.g., vibrations) is the most commonly reported ECH across all groups; although it apparently serves an antipredator function in some species, its adaptive value is unknown in most. Delayed hatching, characterized by metabolic depression or embryonic aestivation, and sometimes followed by a hypoxic cue (flooding), occurs in some turtles and possibly in monitor lizards and crocodilians; in some of these species delayed hatching serves to defer hatching from the dry season until the more favorable conditions of the wet season. Synchronous hatching, whereby sibling eggs hatch synchronously despite vertical thermal gradients in the nest, occurs in some turtles and crocodilians. Although vibrations and vocalizations in hatching-competent embryos can stimulate synchronous hatching, cues promoting developmentally less advanced embryos to catch up with more advanced embryos have not been confirmed. Synchronous hatching may serve to dilute predation risk by promoting synchronous emergence or reduce the period in which smells associated with hatching can attract predators to unhatched eggs. Within species, advancing our understanding of ECH requires three types of studies: (1) experiments identifying hatching cues and the plastic hatching period, (2) experiments disentangling hypotheses about multiple hatching cues, and (3) investigations into the environmental context in which ECH might evolve in different species (major predators or abiotic influences on the egg, embryo, and hatchling). Among species and groups, surveys for ECH are

  3. <em>Neoromicia> Roberts, 1926 (Mammalia Vespertilionidae: correction of gender and etymology

    Directory of Open Access Journals (Sweden)

    Marco Riccucci

    2009-02-01

    Full Text Available Riassunto <em>Neoromicia> Roberts, 1926 (Mammalia, Verspetilionidae: Correzione del genere grammaticale ed etimologia <em>Neoromicia> Roberts, 1926, sinora considerato erroneamente di genere maschile, è in realtà femminile. La sua etimologia deriva quasi certamente dal Greco antico "ρóμιζα", corrispondente al latino "<em>Rumex>" (sorta di giavellotto, per la presenza di un cospicuo sperone calcaneale in <em>Romicia calcarataem>, specie tipo del genere.

  4. Activity-Guided Isolation of Antioxidant Compounds from <em>Rhizophora apiculataem>

    Directory of Open Access Journals (Sweden)

    Hongbin Xiao

    2012-09-01

    Full Text Available <em>Rhizophora apiculataem> (<em>R. apiculataem> contains an abundance of biologically active compounds due its special salt-tolerant living surroundings. In this study, the total phenolic content and antioxidant activities of various extract and fractions of stem of <em>R. apiculataem> were investigated. Results indicated that butanol fraction possesses the highest total phenolic content (181.84 mg/g GAE/g dry extract with strongest antioxidant abilities. Following <em>in vitroem> antioxidant activity-guided phytochemical separation procedures, lyoniresinol-3α-<em>O>-β-arabinopyranoside (1, lyoniresinol-3α-<em>O>-β-rhamnoside (2, and afzelechin-3-<em>O>-L-rhamno-pyranoside (3 were separated from the butanol fraction. These compounds showed more noticeable antioxidant activity than a BHT standard in the DPPH, ABTS and hydroxyl radical scavenging assays. HPLC analysis results showed that among different plant parts, the highest content of 13 was located in the bark (0.068%, 0.066% and 0.011%, respectively. The results imply that the <em>R. apiculataem> might be a potential source of natural antioxidants and 13 are antioxidant ingredients in <em>R. apiculataem>.

  5. The influence of the cations Cu{sup +2}/Co{sup +2}/Nd{sup +3} at the ferrite Mi{sub 0,2}Y{sub 0,3}Zn{sub 0,5}Fe{sub 2}O{sub 4} at different temperatures; Estudo da influencia dos cations Cu{sup +2}/Co{sup +2}/Nd{sup +3} na ferrita Mi{sub 0,2}Y{sub 0,3}Zn{sub 0,5}Fe{sub 2}O{sub 4} em diferentes temperaturas

    Energy Technology Data Exchange (ETDEWEB)

    Lima, U.R., E-mail: ulisandra.lima@ifrn.edu.br [Instituto Federal de Educacao, Ciencia e Tecnologia do Rio Grande do Norte (IFRN), Sao Paulo do Potengi, RN (Brazil); Nasar, R.S.; Nasar, M.C.; Silva, J.E.M. da [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Programa de Pos-Grduacao em Quimica

    2016-07-01

    The work consisted of Ni{sub 0,2}Y{sub 0,3}Zn{sub 0,5}Fe{sub 2}O{sub 4} composition ferrites synthesis ranging copper ions (Cu{sup +2}), cobalt (Co{sup +2}) and neodymium (Nd{sup +3}) whose objective is to evaluate the particle size by the method citrate precursor. After synthesis, the samples were calcined at 350° C and subsequently sintered at 1000° for 3 hours, with controlled heating and cooling rate. The calcined materials were characterized by XRD and SEM showed that the method of the precursor citrate is an effective method. The X-ray diffraction spectra and refinement show good agreement between the experimental peaks and the theoretical spectrum. In Scanning Electron Microscopy (SEM), the samples to 350° C/3h, have dimensions in the micrometer order in all compositions. The average size of the crystals are consistent with the higher definition and intensity of peaks of X-rays, that is, there is high correlation with those obtained by refining method. (author)

  6. Electronic, Magnetic, and Redox Properties of [MFe(3)S(4)] Clusters (M = Cd, Cu, Cr) in Pyrococcus furiosus Ferredoxin.

    Science.gov (United States)

    Staples, Christopher R.; Dhawan, Ish K.; Finnegan, Michael G.; Dwinell, Derek A.; Zhou, Zhi Hao; Huang, Heshu; Verhagen, Marc F. J. M.; Adams, Michael W. W.; Johnson, Michael K.

    1997-12-01

    The ground- and excited-state properties of heterometallic [CuFe(3)S(4)](2+,+), [CdFe(3)S(4)](2+,+), and [CrFe(3)S(4)](2+,+) cubane clusters assembled in Pyrococcus furiosus ferredoxin have been investigated by the combination of EPR and variable-temperature/variable-field magnetic circular dichroism (MCD) studies. The results indicate Cd(2+) incorporation into [Fe(3)S(4)](0,-) cluster fragments to yield S = 2 [CdFe(3)S(4)](2+) and S = (5)/(2) [CdFe(3)S(4)](+) clusters and Cu(+) incorporation into [Fe(3)S(4)](+,0) cluster fragments to yield S = (1)/(2) [CuFe(3)S(4)](2+) and S = 2 [CuFe(3)S(4)](+) clusters. This is the first report of the preparation of cubane type [CrFe(3)S(4)](2+,+) clusters, and the combination of EPR and MCD results indicates S = 0 and S = (3)/(2) ground states for the oxidized and reduced forms, respectively. Midpoint potentials for the [CdFe(3)S(4)](2+,+), [CrFe(3)S(4)](2+,+), and [CuFe(3)S(4)](2+,+) couples, E(m) = -470 +/- 15, -440 +/- 10, and +190 +/- 10 mV (vs NHE), respectively, were determined by EPR-monitored redox titrations or direct electrochemistry at a glassy carbon electrode. The trends in redox potential, ground-state spin, and electron delocalization of [MFe(3)S(4)](2+,+) clusters in P. furiosus ferredoxin are discussed as a function of heterometal (M = Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, and Tl).

  7. Cu patterning on Si substrate using solution-processed Ti-Cu oxide films and electroless plating

    Science.gov (United States)

    Miyazeki, Yusuke; Horiuchi, Yoshio; Noh, Joo-Hyong; Cordonier, Christopher E. J.; Honma, Hideo; Arakawa, Taro

    2016-09-01

    We demonstrated for the first time the Cu patterning on Si using Ti and Cu oxide (TiCu-ox) films patterned by photolithography and electroless plating without etching or surface modification. The TiCu-ox films had a porous structure and acted as adhesion layers. The TiCu-ox films were patterned by photolithography on Si and glass for comparison, followed by Cu deposition by electroless plating. Fine Cu patterns on the patterned TiCu-ox films were formed. The smallest line/space widths on glass and Si were 3.2/0.8 and 3.6/4.4 µm, respectively. The deposited Cu layers had high adhesion strength and low sheet resistance.

  8. Effect of Cu content and temperature on the properties of Cu2ZnSnSe4 solar cells

    Science.gov (United States)

    Sahayaraj, Sylvester; Brammertz, Guy; Buffière, Marie; Meuris, Marc; Vleugels, Jef; Poortmans, Jef

    2016-09-01

    The complexity involved in obtaining pure Kesterite Cu2ZnSnSe4 (CZTSe) thin film primarily arises due to its narrow region of stability, leading to the presence of unavoidable binary selenides of the constituent metals. This study offers an insight on the formation of Cu selenides when the amount of Cu is varied in the precursor from Cu poor to Cu rich. The amount of Cu selenides was found to decrease when the composition of CZTSe absorber approached Cu rich conditions but functional devices were not obtained. Detailed characterizations also showed that the Cu and Sn binary phases were present at the backside interface of CZTSe solar cells. However with an increase in the selenization temperature it was found that the amount of Cu selenides and other secondary phases could be drastically minimized or even eliminated leading to high efficiency devices.

  9. Effect of Cu content and temperature on the properties of Cu2ZnSnSe4 solar cells

    Directory of Open Access Journals (Sweden)

    Sahayaraj Sylvester

    2016-01-01

    Full Text Available The complexity involved in obtaining pure Kesterite Cu2ZnSnSe4 (CZTSe thin film primarily arises due to its narrow region of stability, leading to the presence of unavoidable binary selenides of the constituent metals. This study offers an insight on the formation of Cu selenides when the amount of Cu is varied in the precursor from Cu poor to Cu rich. The amount of Cu selenides was found to decrease when the composition of CZTSe absorber approached Cu rich conditions but functional devices were not obtained. Detailed characterizations also showed that the Cu and Sn binary phases were present at the backside interface of CZTSe solar cells. However with an increase in the selenization temperature it was found that the amount of Cu selenides and other secondary phases could be drastically minimized or even eliminated leading to high efficiency devices.

  10. Corrosion Resistance of Zn and Cu Coated Steel Pipes as a Substitute for Cu Pipe in an Air Conditioner System

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Jae Gyeong; Park, Chan Jin; Hong, Sung Kil [Chonnam National University, Gwangju (Korea, Republic of)

    2009-02-15

    We investigated the corrosion resistance of Zn and Cu coated steel pipes as a substitute for Cu pipe in an air-conditioner system. In addition, the galvanic corrosion tendency between two dissimilar metal parts was studied. The corrosion resistance of the Cu electroplated steel was similar to that of Cu, while the corrosion rate of the Zn electro-galvanized and the galvalume (Zn-55 % Al) coated steels was much higher and not suitable for Cu substitute in artificial sea water and acidic rain environments. Furthermore, the galvanic difference between Cu electroplated steel and Cu was so small that the Cu coated steel pipe can be used as a substitute for Cu pipe in an air-conditioner system.

  11. Effect of the diameter on Cu-Al post retention Efeito do diâmetro na retenção de pinos de Cu-Al

    Directory of Open Access Journals (Sweden)

    Celso Bernardo de Souza Filho

    2004-09-01

    Full Text Available This study compared the resistance to removal by traction of abraded cylindrical metal cast posts of Cu-Al (Goldent-LA. The posts had constant length (9 mm and three different diameters (0.9, 1.3 and 1.7 mm, and were cemented with zinc phosphate cement. The crowns of 36 sound maxillary canines were sectioned, the roots were immersed in resin blocks and the root canals were endodontically treated. The teeth were divided into three groups to be prepared and standardized with the use of a parallelometer with the following burs: Group 1 - Largo n. 2; Group 2 - Largo n. 4; Group 3 - Largo n. 6. The posts were molded with chemically activated resin and after casting they were abraded and their dimensions were confirmed with a digital caliper. After cementation of the posts in the prepared root canals, the samples were kept at 37ºC in distilled water for 7 days and subsequently submitted to the traction test in a universal testing machine (Instron 4444. The results showed no statistical difference between the groups. Diameter variation (0.9 mm, 1.3 mm and 1.7 mm in abraded cylindrical posts cemented with zinc phosphate did not affect resistance to removal.Este estudo in vitro comparou a resistência à remoção por tração de núcleos metálicos fundidos em liga de Cu-Al (Goldent-LA cilíndricos, jateados, de comprimento constante igual a 9 mm, cimentados com cimento de fosfato de zinco e com três diferentes diâmetros: 0,9 mm, 1,3 mm e 1,7 mm. Trinta e seis caninos superiores hígidos tiveram suas coroas seccionadas, sendo as raízes incluídas em blocos de resina acrílica, e os canais, tratados endodonticamente. Os dentes foram divididos em três grupos para serem preparados e padronizados com o auxílio de um paralelômetro com as seguintes brocas: Grupo 1 - Largo nº 2; Grupo 2 - Largo nº 4; Grupo 3 - Largo nº 6. Os núcleos foram moldados com resina acrílica ativada quimicamente e, após a fundição, foram jateados e tiveram as suas

  12. Teor de nutrientes em mudas de cedro (Cedrela fissilis Vell. submetidas a doses crescentes de níquel, em solução nutritiva

    Directory of Open Access Journals (Sweden)

    Paiva Haroldo Nogueira de

    2002-01-01

    Full Text Available O efeito da aplicação de níquel sobre o teor de nutrientes na raiz, no caule e nas folhas de mudas de cedro (Cedrela fissilis Vell. foi estudado em um experimento realizado em casa de vegetação do Departamento de Ciência do Solo da Universidade Federal de Lavras. As mudas foram cultivadas em solução nutritiva de Clark e submetidas a doses crescentes de Ni: 0, 42, 84, 169 e 252 mimol. O experimento foi conduzido em delineamento estatístico de blocos ao acaso, e após 60 dias de exposição ao metal pesado foram feitas avaliações do teor de macro e de micronutrientes na matéria seca de raiz, caule e folha. Os resultados mostraram que a aplicação de níquel aumentou o teor de P, praticamente não afetou o teor de K e de S, no entanto reduziu o teor de Ca e de Mg. Os teores de Cu, Fe e Mn, de modo geral, sofreram redução, ao passo que o teor de Zn foi pouco afetado. O teor de Ni, na matéria seca de raiz, caule e folha, elevou-se com o aumento das doses deste metal pesado, que mostrou ser móvel nas plantas analisadas.

  13. Electrical Breakdown Characteristic of Nanostructured W-Cu Contacts Materials

    Institute of Scientific and Technical Information of China (English)

    WANG Junbo; CHEN Wen'ge; DING Bingjun

    2006-01-01

    Nanostructured (NS) W- Cu composite powder was prepared by mechanical alloying ( MA ), and nanostructured bulk of W- Cu contact material was fabricated by hot press sintering in an electrical vacuum furnace. The microstructure, electric conductivity, hardness and break down voltage of NS W-Cu alloys were measured and compared to those of conventional W- Cu alloys prepared by powder metallurgy. The experimental results show that microstructural refinement and uniformity can improve the breakdown behavior and the electric arc stability of nanostructured W- Cu contacts materials. Also, the nanostructured W- Cu contact material shows the characteristic of spreading electric arcs, which is of benefit to electric arc erosion.

  14. Busca de estruturas em grandes escalas em altos redshifts

    Science.gov (United States)

    Boris, N. V.; Sodrã©, L., Jr.; Cypriano, E.

    2003-08-01

    A busca por estruturas em grandes escalas (aglomerados de galáxias, por exemplo) é um ativo tópico de pesquisas hoje em dia, pois a detecção de um único aglomerado em altos redshifts pode por vínculos fortes sobre os modelos cosmológicos. Neste projeto estamos fazendo uma busca de estruturas distantes em campos contendo pares de quasares próximos entre si em z Â3 0.9. Os pares de quasares foram extraídos do catálogo de Véron-Cetty & Véron (2001) e estão sendo observados com os telescópios: 2,2m da University of Hawaii (UH), 2,5m do Observatório de Las Campanas e com o GEMINI. Apresentamos aqui a análise preliminar de um par de quasares observado nos filtros i'(7800 Å) e z'(9500 Å) com o GEMINI. A cor (i'-z') mostrou-se útil para detectar objetos "early-type" em redshifts menores que 1.1. No estudo do par 131046+0006/J131055+0008, com redshift ~ 0.9, o uso deste método possibilitou a detecção de sete objetos candidatos a galáxias "early-type". Num mapa da distribuição projetada dos objetos para 22 < i' < 25 observou-se que estas galáxias estão localizadas próximas a um dos quasares e há indícios de que estejam aglomeradas dentro de um área de ~ 6 arcmin2. Se esse for o caso, estes objetos seriam membros de uma estrutura em grande escala. Um outro argumento em favor dessa hipótese é que eles obedecem uma relação do tipo Kormendy (raio equivalente X brilho superficial dentro desse raio), como a apresentada pelas galáxias elípticas em z = 0.

  15. Atom probe study of Cu-poor to Cu-rich transition during Cu(In,Ga)Se{sub 2} growth

    Energy Technology Data Exchange (ETDEWEB)

    Couzinie-Devy, F.; Cadel, E.; Pareige, P. [Groupe de Physique des Materiaux (GPM), UMR 6634 CNRS, Universite et INSA de Rouen, Avenue de l' Universite BP 12, 76801 Saint Etienne du Rouvray (France); Barreau, N.; Arzel, L. [Institut des Materiaux Jean Rouxel (IMN), UMR 6502 CNRS, 2 rue de la Houssiniere BP 32229, 44322 Nantes cedex 3 (France)

    2011-12-05

    Atomic scale chemistry of polycrystalline Cu(In,Ga)Se{sub 2} (CIGSe) thin film has been characterized at key points of the 3-stage process using atom probe tomography. 3D atom distributions have been reconstructed when the layer is Cu-poor ([Cu]/([Ga] + [In]) < 1), Cu-rich ([Cu]/([Ga] + [In]) > 1), and at the end of the process. Particular attention has been devoted to grain boundary composition and Na atomic distribution within the CIGSe layer. Significant variation of composition is highlighted during the growing process, providing fundamental information helping the understanding of high efficiency CIGSe formation.

  16. Simulations of Metal Cu in Heating Process

    Institute of Scientific and Technical Information of China (English)

    ZHANG, Tao(张弢); WU, Ai-Ling(吴爱玲); GUAN, Li(管立); QI, Yuan-Hua(齐元华)

    2004-01-01

    Based on the Finnis-Sinsclair (FS) many-body potential model, the melting process of a system, which consists of 500 Cu atoms, controlled by period boundary condition has been simulated. The means of pair correlation function, mean square displacement and Honeycutt-Anderson bonded pair have been used to characterize the melting behavior of Cu at different heating rates. The simulation indicates that melting point of metal Cu is 1444 K during a continuous heating process, and the calculated diffusion constant at the melting point is 4.31×10-9 m2/s. These results are better than those from the EAM method, showing that the FS potential model works well in some disordered systems.

  17. Oxide Nanotube Analogues: CuO Nanobarrels

    Energy Technology Data Exchange (ETDEWEB)

    H. H. Farrell; R. D. Parra

    2011-11-01

    The principle 'form follows function' which dominated much of twentieth century architechture and industrial design has its parallel on the nanolevel in the concept of 'function follows form'. This has been realized in many technologically valuable ways on this level via nanoparticles such as nanotubes and quantum dots, for example. Now, a new material, copper oxide (CuO) nanobarrels, offers still another opportunity to exploit unusual form to obtain new functionality. Recently, CuO 'rings' on the order of 100 nm diameter have been observed experimentally by El-Azab and Liang (2003). In a separate effort, we have used first principles density functional calculations to investigate smaller, single walled CuO structures that appear to be nanotubes or nanobarrels with a square unit mesh rather than the hexagonal mesh of carbon nanotubes. These structures are unique and novel, and almost certainly will yield fascinating results when studied experimentally.

  18. Access to a CuII–O–CuII Motif: Spectroscopic Properties, Solution Structure, and Reactivity

    Science.gov (United States)

    Haack, Peter; Kärgel, Anne; Greco, Claudio; Dokic, Jadranka; Braun, Beatrice; Pfaff, Florian F.; Mebs, Stefan; Ray, Kallol; Limberg, Christian

    2013-01-01

    We report a complex with a rare CuII–O–CuII structural motif that is stable at room temperature, which allows its in-depth characterization by a variety of spectroscopic methods. Interest in such compounds is fueled by the recent discovery that a CuII–O–CuII species on the surface of Cu-ZSM-5 is capable of oxidizing methane to methanol and this in turn ties into mechanistic discussions on the methane oxidation at the dicopper site within the particulate methane monooxygenase. For the synthesis of our Cu2O complex we have developed a novel, neutral ligand system, FurNeu, exhibiting two N-(N',N'-dimethylaminoethyl)(2-pyridylmethyl)amino binding pockets connected by a dibenzofuran spacer. The reaction of FurNeu with CuCl yielded [FurNeu](Cu2(μ-Cl))(CuCl2), 1, demonstrating the geometric potential of the ligand to stabilize Cu–X–Cu moieties. A CuI precursor with weakly coordinating anions was chosen in the next step, namely [Cu(NCCH3)4]OTf, which led to the formation of [FurNeu](Cu(NCCH3))2(OTf)2, 3. Treatment of 3 with O2 or PhIO led to identical green solutions, whose UV/Vis spectra were markedly different from the one displayed by [FurNeu](Cu)2(OTf)4, 4, prepared independently from FurNeu and Cu(OTf)2. Further investigations including PhIO consumption experiments, NMR and UV/Vis spectroscopy, HR-ESI mass spectrometry and protonation studies led to the identification of the green product as [FurNeu](Cu2(μ-O))(OTf)2, 5. DOSY NMR spectroscopy confirmed its monomeric character. Over longer periods of time 5 decomposes to give [Cu(picoloyl)2], formed through an oxidative N-dealkylation reaction followed by further oxidation of the ligand. Due to its slow decomposition reaction all attempts to crystallize 5 failed. However, its structure in solution could be determined by EXAFS analysis in combination with DFT calculations, which revealed a Cu–O–Cu angle that amounts to 105.17°. Moreover, TDDFT calculations helped to rationalize the UV/Vis absorptions

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-04-15

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

  20. Characterization of Cu-exchanged SSZ-13: a comparative FTIR, UV-Vis, and EPR study with Cu-ZSM-5 and Cu-β with similar Si/Al and Cu/Al ratios

    DEFF Research Database (Denmark)

    Giordanino, Filippo; Vennestrøm, Peter N. R.; Lundegaard, Lars Fahl

    2013-01-01

    revealed the presence of different Cu2+ species. New data and discussion are devoted to (i) [Cu–OH]+ species likely balanced by one framework Al atom; (ii) mono(μ-oxo)dicopper [Cu2(μ-O)]2+ dimers observed in Cu-ZSM-5 and Cu-β, but not in Cu-SSZ-13. UV-Vis-NIR spectra of O2 activated samples reveal......Cu-SSZ-13 has been characterized by different spectroscopic techniques and compared with Cu-ZSM-5 and Cu-β with similar Si/Al and Cu/Al ratios and prepared by the same ion exchange procedure. On vacuum activated samples, low temperature FTIR spectroscopy allowed us to appreciate a high...... concentration of reduced copper centres, i.e. isolated Cu+ ions located in different environments, able to form Cu+(N2), Cu+(CO)n (n = 1, 2, 3), and Cu+(NO)n (n = 1, 2) upon interaction with N2, CO and NO probe molecules, respectively. Low temperature FTIR, DRUV-Vis and EPR analysis on O2 activated samples...

  1. Antibacterial activity and cytocompatibility of Cu-Ti-O nanotubes.

    Science.gov (United States)

    Hang, Ruiqiang; Gao, Ang; Huang, Xiaobo; Wang, Xiaoguang; Zhang, Xiangyu; Qin, Lin; Tang, Bin

    2014-06-01

    TiO2 nanotubes (NTs) have favorable biological properties, but the poor antibacterial activity limits their application especially in orthopedics fields. In this article, Cu-Ti-O nanotubes with different Cu contents are fabricated on sputtered TiCu films. Scanning electron microscopy reveals the NTs can be formed on sputtered TiCu films when the Cu content is less than 14.6 at %. X-ray photoelectron spectroscopy results indicate the NTs are consist of CuO mixed with TiO2 and the Cu content in NTs decreases dramatically compared with that in TiCu films. Biological experiments show that although these NTs have poor release antibacterial activity, their contact antibacterial activity has proven to be excellent, indicating the NT surface can effectively inhibit biomaterial-associated infections. The cytocompatibility of the NTs is closely related to the Cu content and when its content is relatively low (1.01 at %), there is no appreciable cytotoxicity. So Cu-Ti-O NTs with 1 at % Cu may be suitable to achieve proper antibacterial activity and desired cytocompatibility. The Cu-Ti-O NTs integrate the favorable antibacterial activity of Cu and excellent biological properties of TiO2 NTs therefore have potential applications in orthopedics, dentistry, and other biomedical fields.

  2. Synthesis of Cu/Cu2O nanoparticles by laser ablation in deionized water and their annealing transformation into CuO nanoparticles

    KAUST Repository

    Gondal, M. A.

    2013-08-01

    Nano-structured Cupric Oxide (CuO) has been synthesized using pulsed laser ablation of pure copper in water using Q-switched pulsed laser beam of 532 nm wavelength and, 5 nanosecond pulse duration and laser pulse energy of 100 mJ/pulse. In the initial unannealed colloidal suspension, the nanoparticles of Copper (Cu) and Cuprious oxide (Cu2O) were identified. Further the suspension was dried and annealed at different temperatures and we noticed the product (Cu/Cu2O) was converted predominantly into CuO at annealing temperature of 300 \\'C for 3 hours. As the annealing temperature was raised from 300 to 900 \\'C, the grain sizes of CuO reduced to the range of 9 to 26 nm. The structure and the morphology of the prepared samples were investigated using X-ray diffraction and Transmission Electron Microscope. Photoluminescence and UV absorption spectrometrystudies revealed that the band gap and other optical properties of nano-structured CuO were changed due to post annealing. Fourier transform spectrometry also confirmed the transformation of Cu/Cu2O into CuO. Copyright © 2013 American Scientific Publishers All rights reserved.

  3. Characterization of p-CuI prepared by the SILAR technique on Cu-tape/n-CuInS{sub 2} for solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Sankapal, B.R. [Hahn-Meitner-Institut, Glienicker Strasse 100, D-14109, Berlin (Germany)]. E-mail: brsankapal@rediffmail.com; Ennaoui, A. [Hahn-Meitner-Institut, Glienicker Strasse 100, D-14109, Berlin (Germany); Guminskaya, T. [Hahn-Meitner-Institut, Glienicker Strasse 100, D-14109, Berlin (Germany); Dittrich, Th. [Hahn-Meitner-Institut, Glienicker Strasse 100, D-14109, Berlin (Germany); Bohne, W. [Hahn-Meitner-Institut, Glienicker Strasse 100, D-14109, Berlin (Germany); Roehrich, J. [Hahn-Meitner-Institut, Glienicker Strasse 100, D-14109, Berlin (Germany); Strub, E. [Hahn-Meitner-Institut, Glienicker Strasse 100, D-14109, Berlin (Germany); Lux-Steiner, M.Ch. [Hahn-Meitner-Institut, Glienicker Strasse 100, D-14109, Berlin (Germany)

    2005-06-01

    CuI has been synthesized at room temperature on Cu-tape/n-CuInS{sub 2} by using the SILAR technique (successive ionic layer adsorption and reaction). The influence of wet chemical iodine treatment on the CuI has been investigated in more detail. The films were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), elastic recoil detection analysis (ERDA) and surface photovoltage (SPV) techniques. The CuI films contain the no. gammano. -phase of the Zinkblende structure. The crystallites are preferentially oriented in the (111) direction. After wet chemical iodine treatment, the fibrous surface morphology changed to a more dense CuI film with larger crystallites. Oxides could not be detected on the CuI surface. The density of surface states of CIS decreased after the CuI deposition. The importance of the wet chemical iodine treatment for the performance of Cu-tape/n-CuInS{sub 2}/p-CuI solar cells has been demonstrated.

  4. Crystallization features of YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} in the Y{sub 2}BaCuO{sub 5}-BaCuO{sub 2}-CuO and Y{sub 2}Cu{sub 2}O{sub 5}-BaCuO{sub 2} systems

    Energy Technology Data Exchange (ETDEWEB)

    Gurskii, L.I. [Belarusian State University of Informatics Science and Radioelectronics, Minsk (Belarus); Saad, A.M. [Al-Balqua Applied University, Salt (Jordan); Truhan, V.M.; Haliakevich, T.V. [Joint Institute of Solid State and Semiconductor Physics, NAS Belarus, Minsk (Belarus); Kalanda, N.A.

    2008-06-15

    Based on the data of X-ray phase and microstructure analysis, the sample composition was optimized in order to provide maximum size of the textured macrograins of YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} and of the crystallites in the Y{sub 2}BaCuO{sub 5}-BaCuO{sub 2}-CuO, Y{sub 2}Cu{sub 2}O{sub 5}-BaCuO{sub 2} systems. The growth rate has been studied and the YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} growth activation energy has been calculated for the samples of Y{sub 2}BaCuO{sub 5}+3BaCuO{sub 2}+2.3CuO, Y{sub 2}BaCuO{sub 5}+3BaCuO{sub 2}+0.6CuO, and Y{sub 2}Cu{sub 2}O{sub 5}+3.5BaCuO{sub 2} compounds in the temperature range of 1240-1270 K for the case of use of the Y{sub 2}Cu{sub 2}O{sub 5} and Y{sub 2}BaCuO{sub 5} precursors with an average grain diameter of 10 {mu}m and 1 mm. A crystallization mechanism of YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} in the Y{sub 2}BaCuO{sub 5}-BaCuO{sub 2}-CuO and Y{sub 2}Cu{sub 2}O{sub 5}-BaCuO{sub 2} systems in the case of different sizes of Y{sub 2}BaCuO{sub 5} and Y{sub 2}Cu{sub 2}O{sub 5} precursor grains was proposed and validated. (copyright 2008 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  5. Corrosion and runoff rates of Cu and three Cu-alloys in marine environments with increasing chloride deposition rate.

    Science.gov (United States)

    Odnevall Wallinder, Inger; Zhang, Xian; Goidanich, Sara; Le Bozec, Nathalie; Herting, Gunilla; Leygraf, Christofer

    2014-02-15

    Bare copper sheet and three commercial Cu-based alloys, Cu15Zn, Cu4Sn and Cu5Al5Zn, have been exposed to four test sites in Brest, France, with strongly varying chloride deposition rates. The corrosion rates of all four materials decrease continuously with distance from the coast, i.e. with decreasing chloride load, and in the following order: Cu4Sn>Cu sheet>Cu15Zn>Cu5Al5Zn. The patina on all materials was composed of two main layers, Cu2O as the inner layer and Cu2(OH)3Cl as the outer layer, and with a discontinuous presence of CuCl in between. Additional minor patina constituents are SnO2 (Cu4Sn), Zn5(OH)6(CO3)2 (Cu15Zn and Cu5Al5Zn) and Zn6Al2(OH)16CO3·4H2O/Zn2Al(OH)6Cl·2H2O/Zn5Cl2(OH)8·H2O and Al2O3 (Cu5Al5Zn). The observed Zn- and Zn/Al-containing corrosion products might be important factors for the lower sensitivity of Cu15Zn and Cu5Al5Zn against chloride-induced atmospheric corrosion compared with Cu sheet and Cu4Sn. Decreasing corrosion rates with exposure time were observed for all materials and chloride loads and attributed to an improved adherence with time of the outer patina to the underlying inner oxide. Flaking of the outer patina layer was mainly observed on Cu4Sn and Cu sheet and associated with the gradual transformation of CuCl to Cu2(OH)3Cl of larger volume. After three years only Cu5Al5Zn remains lustrous because of a patina compared with the other materials that appeared brownish-reddish. Significantly lower release rates of metals compared with corresponding corrosion rates were observed for all materials. Very similar release rates of copper from all four materials were observed during the fifth year of marine exposure due to an outer surface patina that with time revealed similar constituents and solubility properties. Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved.

  6. Beta-decay of {sup 56}Cu

    Energy Technology Data Exchange (ETDEWEB)

    Ramdhane, M.; Baumann, P.; Knipper, A.; Walter, G. [Institute de Recherches Subatomiques, 67 - Strasbourg (France); Janas, Z.; Plochocki, A. [Warsaw Univ. (Poland). Inst. of Experimental Physics; Aeystoe, J.; Dendooven, P.; Jokinen, A.; Oinonen, M.; Pentilae, H. [Jyvaeskylae Univ. (Finland); Liu, W.; Grawe, H.; Hu, Z.; Kirchner, R.; Klepper, O.; Roeckl, E. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany); Gorska, M. [Warsaw Univ. (Poland). Inst. of Experimental Physics]|[Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany); Fujita, Y. [Osaka Univ. (Japan); Brown, B.A. [Michigan State Univ., East Lansing, MI (United States)

    1998-02-01

    By measuring positrons and {beta}-delayed {gamma}-rays emitted from mass-separated sources, the decay of {sup 56}Cu(4{sup +},T{sub z}=-1,T=1) to states in the doubly-magic nucleus {sup 56}Ni was studied for the first time. The half-life of {sup 56}Cu was measured to be 78(15) ms, and four {beta}-delayed {gamma}-rays were assigned to its decay. The resulting experimental data on Fermi and Gamow-Teller strength are compared with shell-model predictions. (orig.)

  7. Correlaciones cuánticas y grafos

    OpenAIRE

    López Tarrida, Antonio José

    2014-01-01

    Esta tesis doctoral trata de diversos aspectos de la teoría cuántica (TC), que abarcan desde el campo de los fundamentos de la disciplina (en particular, la búsqueda de un conjunto de principios que seleccionen y distingan a la TC en el panorama de las teorías probabilísticas generales) hasta el reino de las aplicaciones en información y computación cuánticas.   Todos los problemas que hemos abordado en nuestra investigaci&oacut...

  8. Chemical Profiles and Identification of Key Compound Caffeine in Marine-Derived Traditional Chinese Medicine <em>Ostreae em>concha>

    Directory of Open Access Journals (Sweden)

    Hong-Bing Liu

    2012-05-01

    Full Text Available To compare the chemical differences between the medicinal and<em> em>cultured oyster shells, their chemical profiles were investigated. Using the ultra performance liquid chromatography-electron spraying ionization-mass spectrometry (UPLC-ESI-MS, combined with principal component analysis (PCA and orthogonal projection to latent structures discriminant analysis (OPLS-DA, the discrimination of the chemical characteristics among the medicinal and cultured oyster shells was established. Moreover, the chemometric analysis revealed some potential key compounds. After a large-scale extraction and isolation, one target key compound was unambiguously identified as caffeine (1 based on extensive spectroscopic data analysis (1D and 2D NMR, MS, and UV and comparison with literature data.

  9. Superconductivity of Cu/CuOx interface formed by shock-wave pressure

    Science.gov (United States)

    Shakhray, D. V.; Avdonin, V. V.; Palnichenko, A. V.

    2016-11-01

    A mixture of powdered Cu and CuO has been subjected to shock-wave pressure of 350 kbar with following quenching of the vacuum-encapsulated product to 77 K. The ac magnetic susceptibility measurements of the samples have revealed metastable superconductivity with Tc ≈ 19 K, characterized by glassy dynamics of the shielding currents below Tc . Comparison of the ac susceptibility and the DC magnetization measurements infers that the superconductivity arises within the granular interfacial layer formed between metallic Cu and its oxides due to the shock-wave treatment.

  10. Electrodeposition and Characterization of CuTe and Cu2Te Thin Films

    Directory of Open Access Journals (Sweden)

    Wenya He

    2015-01-01

    Full Text Available An electrodeposition method for fabrication of CuTe and Cu2Te thin films is presented. The films’ growth is based on the epitaxial electrodeposition of Cu and Te alternately with different electrochemical parameter, respectively. The deposited thin films were characterized by X-ray diffraction (XRD, field emission scanning electronic microscopy (FE-SEM with an energy dispersive X-ray (EDX analyzer, and FTIR studies. The results suggest that the epitaxial electrodeposition is an ideal method for deposition of compound semiconductor films for photoelectric applications.

  11. Synthesis, Crystal Structure, and Electroconducting Properties of a 1D Mixed-Valence Cu(I–Cu(II Coordination Polymer with a Dicyclohexyl Dithiocarbamate Ligand

    Directory of Open Access Journals (Sweden)

    Kenji Nakatani

    2015-04-01

    Full Text Available A new mixed-valence Cu(I–Cu(II 1D coordination polymer, [CuI4CuIIBr4(Cy2dtc2]n, with an infinite chain structure is synthesized by the reaction of Cu(Cy2dtc2 (Cy2dtc− = dicyclohexyl dithiocarbamate, C13H22NS2 with CuBr·S(CH32. The as-synthesized polymer consists of mononuclear copper(II units of CuII(Cy2dtc2 and tetranuclear copper(I cluster units, CuI4Br4. In the cluster unit, all the CuI ions have distorted trigonal pyramidal coordination geometries, and the CuI–CuI or CuI–CuII distances between the nearest copper ions are shorter than the sum of van der Waals radii for Cu–Cu.

  12. Tratamento da dor em queimados

    Directory of Open Access Journals (Sweden)

    Rodrigo José Alencar de Castro

    2013-02-01

    Full Text Available JUSTIFICATIVA E OBJETIVOS: Apesar dos avanços, ainda é observado manejo analgésico inadequado dos pacientes com queimaduras. O objetivo desta revisão foi coletar dados sobre tratamento da dor em queimados. CONTEÚDO: Foi feita revisão sobre os mecanismos de dor, avaliação do paciente com queimadura e o tratamento farmacológico e não farmacológico. CONCLUSÕES: O manejo da dor em pacientes vítimas de queimaduras ainda é um desafio por parte da equipe multiprofissional. A avaliação frequente e contínua da resposta apresentada pelo paciente é muito importante, tendo em vista os vários momentos por que passa o paciente internado em decorrência de uma queimadura, além de uma terapêutica combinada com medicações analgésicas e medidas não farmacológicas. Entender a complexidade de alterações fisiopatológicas, psicológicas e bioquímicas apresentadas por um paciente em tratamento de queimadura é o primeiro passo para alcançar o sucesso no seu manejo analgésico.

  13. Minerais em melados e em caldos de cana Minerals in sugar cane syrup and cane juice

    Directory of Open Access Journals (Sweden)

    Fernanda dos Santos Nogueira

    2009-12-01

    Full Text Available A cana-de-açúcar está entre as culturas que apresenta larga escala de adaptações às condições climáticas, sendo utilizada para a fabricação de diversos produtos. Dentre os produtos derivados da cana-de-açúcar, o melado é tido popularmente como um alimento rico em ferro. Este trabalho objetivou conhecer a concentração de alguns minerais em melados comerciais e em melados preparados com equipamentos de aço inoxidável. Ao todo foram 20 amostras, 10 de cada tipo. As amostras foram preparadas para análise por oxidação da matéria orgânica por via úmida e os teores de Ca, Mg, Cu, Mn, Zn e Fe foram determinados por espectroscopia de absorção atômica, Na e K por fotometria de chama e P por colorimetria. Concluiu-se, com este trabalho, que os teores médios dos minerais Fe, P, Na e Mg foram significativamente mais elevados nos melados comerciais do que nos melados feitos com equipamentos inox. O contrário foi encontrado para o mineral cálcio, que apresentou teor mais elevado nos melados feitos no laboratório, mas condizentes com os teores encontrados nos caldos de cana. Não houve diferença significativa nos teores dos demais minerais.Sugar cane is an easily adaptable crop to diverse climate conditions, and it is used in the manufacturing of many different products. Among those products is the syrup, which is popularly known to be good sources of iron. In this work, we aimed to measure the concentration of some minerals in commercial sugar cane syrup brands and syrup prepared in the laboratory using stainless steel equipment. A total of 20 samples were analyzed, 10 of commercial brands and ten prepared in the laboratory. The samples were prepared by wet-air oxidation of organic matter and the contents of Ca, Mg, Cu, Mn, Zn, and Fe were determined by atomic absorption. Na and K were determined by photometry and P by colorimetry. It was found that the mean concentration of Fe, P, Na, and Mn were higher in the commercial

  14. Botulismo tipo C em perus em Minas Gerais, Brasil

    OpenAIRE

    Lobato,Francisco Carlos Faria; Salvarani,Felipe Masiero; Silva,Rodrigo Otávio Silveira; Assis,Ronnie Antunes de; Lago,Luis Alberto do; Carvalho Filho,Maurício Baltazar de; Martins,Nelson Rodrigo da Silva

    2009-01-01

    O botulismo é uma intoxicação causada pela ingestão das toxinas produzidas pelo Clostridium botulinum, que acomete mamíferos e aves e é caracterizado por um quadro de paralisia flácida. Neste trabalho, é descrito um surto de botulismo em perus, ocorrido no município de Santa Luzia, região metropolitana de Belo Horizonte, Minas Gerais. Os animais apresentavam incoordenação motora, paralisia flácida das patas, asas e pescoço. Em um intervalo de 24 horas, todos os 29 animais do plantel vieram a ...

  15. Electrodeposited NiCu Alloy Catalysts for Glucose Oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Jieun; Park, Hansoo; Kim, Sookil [Chung-Ang Univ., Seoul (Korea, Republic of); Ahn, Sang Hyun; Jang, Jong Hyun [Korea Institute of Science and Technology, Seoul (Korea, Republic of)

    2014-07-15

    NiCu alloys have been suggested as potential candidates for catalysts in glucose oxidation. In this study, NiCu alloys with different compositions were prepared on a glassy carbon substrate by changing the electrodeposition potential to examine the effect of Ni/Cu ratios in alloys on catalytic activity toward glucose oxidation. Cyclic voltammetry and chronoamperometry showed that NiCu alloys had higher catalytic activity than pure Ni and Cu catalysts. Especially, Ni{sub 59}Cu{sub 41} had superior catalytic activity, which was about twice that of Ni at a given oxidation potential. X-ray analyses showed that the oxidation state of Ni in NiCu alloys was increased with the content of Cu by lattice expansion. Ni components in alloys with higher oxidation state were more effective in the oxidation of glucose.

  16. Design of Cu8Zr5-based bulk metallic glasses

    Science.gov (United States)

    Yang, L.; Xia, J. H.; Wang, Q.; Dong, C.; Chen, L. Y.; Ou, X.; Liu, J. F.; Jiang, J. Z.; Klementiev, K.; Saksl, K.; Franz, H.; Schneider, J. R.; Gerward, L.

    2006-06-01

    Basic polyhedral clusters have been derived from intermetallic compounds at near-eutectic composition by considering a dense packing and random arrangement of atoms at shell sites. Using such building units, bulk metallic glasses can be formed. This strategy was verified in the Cu-Zr binary system, where we have demonstrated the existence of Cu8Zr5 icosahedral clusters in Cu61.8Zr38.2, Cu64Zr36, and Cu64.5Zr35.5 amorphous alloys. Furthermore, ternary bulk metallic glasses can be developed by doping the basic Cu-Zr alloy with a minority element. This hypothesis was confirmed in systems (Cu0.618Zr0.382)100-xNbx, where x =1.5 and 2.5at.%, and (Cu0.618Zr0.382)98Sn2. The present results may open a route to prepare amorphous alloys with improved glass forming ability.

  17. Fuzzy analytical hierarchy process and GIS for predictive cu -au ...

    African Journals Online (AJOL)

    Fuzzy analytical hierarchy process and GIS for predictive cu -au porphyry in ... process (Fuzzy AHP) that is the most popular multi-criteria decision-making techniques. ... for predictive Mineral prospectively mapping (MPM) for Cu -Au porphyry.

  18. Effects of Cu on the content of chlorophylls and secondary metabolites in the Cu-hyperaccumulator lichen Stereocaulon japonicum.

    Science.gov (United States)

    Nakajima, Hiromitsu; Hara, Kojiro; Yamamoto, Yoshikazu; Itoh, Kiminori

    2015-03-01

    Understanding the relationship between Cu and Cu-hyperaccumulator lichens is important for their application in monitoring and assessing heavy metal pollution. We investigated the Cu-hyperaccumulator lichen Stereocaulon japonicum at several Cu-polluted and control sites in Japan, and found the lichen to be widely distributed. Its concentrations of Cu, chlorophylls, and secondary metabolites, chlorophyll-related indices, and absorption spectra were measured, and we observed negative effects of Cu on these concentrations and indices. For highly Cu-polluted samples (>100ppm dry weight), however, we found significant linear correlations between Cu and chlorophyll concentrations. This can be considered as the response of the photobiont in S. japonicum to Cu stress. In highly Cu-polluted samples the chlorophyll-related indices and concentration of total secondary metabolites were almost constant regardless of Cu concentration. This suggests that the increase in chlorophyll concentration with the increase in Cu concentration enhances photosynthetic productivity per unit biomass, which will allow the production of extra structure and energy for maintaining the chlorophyll-related indices under Cu stress. The relationship between the increase in chlorophyll concentration of S. japonicum and the decrease in secondary metabolite concentration of the lichen can be explained by considering the balance of carbohydrates in the lichen. We found that a spectral index A372-A394 can be a useful index of the concentrations of Cu and total secondary metabolites in S. japonicum. These findings show the adjustment of the content of chlorophylls and secondary metabolites in S. japonicum to Cu stress, and provide a better understanding of the relationship between Cu and the Cu-hyperaccumulator lichen.

  19. One-Pot Synthesis of Cu2O/Cu Self-Assembled Hollow Nanospheres with Enhanced Photocatalytic Performance

    Directory of Open Access Journals (Sweden)

    Bo Zhou

    2014-01-01

    Full Text Available Cu2O/Cu hollow spheres are prepared using one-pot template-free solvent-thermal synthesis route with (CH3COO2Cu·H2O as a precursor. With the reaction time increasing gradually from 2 h to 20 h, the morphology of the Cu2O/Cu evolves from nanoparticle to hollow nanosphere. The hollow structure is obtained when the cooling rate falls down to 0.7°C/min. And the content of Cu in the hollow spheres also can be easily controlled by adjusting the solvent-thermal synthesis time. Using photocatalytic degradation of phenol as the probe molecules under visible-light illumination, we have investigated the influence of hollow structure on the photocatalytic activity of Cu2O/Cu. The prepared hollow sphere Cu2O/Cu particles exhibited a higher photodegradation capability than nanoparticles and solid spheres. When the content of Cu lies in the range of 11–86 wt%, the samples exhibit higher photocatalytic performance, indicating that the Cu2O/Cu particles with hollow structure are promising candidates for the processing of pollutants.

  20. Effect of Cu concentration on the semi-solid deformation behavior and microstructure of Ti–Cu alloy

    Directory of Open Access Journals (Sweden)

    Yong-Nan Chen

    2015-05-01

    Full Text Available The semi-solid compressive deformation behavior of Ti–Cu alloys was investigated by Gleeble-3500 hot simulator at the deformation temperatures ranging from 1273 to 1473 K with strain rates ranging from 5×10−3 to 5×10−1 s−1. The relationship between Cu concentration and flow stress was analyzed, and the deformation apparent activation energy was also calculated. The results show that Cu concentration has significant influence on the flows’ behavior of Ti–Cu alloys, especially at high semi-solid deformation temperatures. The Ti–14Cu exhibits the highest flow stress at 1273 and 1373 K, Ti–2.5Cu alloy exhibits the highest flow stress at 1473 K, and Ti–7Cu alloy shows the lowest flow stress at all tested temperatures, which corresponds to liquid fraction caused by varied Cu concentration and the deformation temperature. The difference in microstructure suggests that the shape and distribution of Ti2Cu precipitates are significantly affected by Cu concentration. The increase in Cu concentration leads to the growth and precipitation of acicular Ti2Cu along grain boundaries at high semi-solid deformation temperatures. The deformation apparent activation energy of Ti–14Cu alloy significantly decreases from solid deformation to semi-solid deformation owing to the change in main deformation mechanism from plastic deformation of solid particles to solid particles’ slippage and rotation of grain boundaries.

  1. Effect of ELF e.m. fields on metalloprotein redox-active sites

    CERN Document Server

    De Ninno, A; Ferrari, V; Gerardi, G; Barbaro, F; Badon, T; Bernardini, D

    2008-01-01

    The peculiarity of the distribution and geometry of metallic ions in enzymes pushed us to set the hypothesis that metallic ions in active-site act like tiny antennas able to pick up very feeble e.m. signals. Enzymatic activity of Cu2+, Zn2+ Superoxide Dismutase (SOD1) and Fe2+ Xanthine Oxidase (XO) has been studied, following in vitro generation and removal of free radicals. We observed that Superoxide radicals generation by XO is increased by a weak field having the Larmor frequency fL of Fe2+ while the SOD1 kinetics is sensibly reduced by exposure to a weak field having the frequency fL of Cu2+ ion.

  2. Produção de rúcula em hidroponia com diferentes concentrações de cobre Yield of roquette in hydroponic system, with different copper concentrations in the nutrient solution

    Directory of Open Access Journals (Sweden)

    Leilson C. Grangeiro

    2003-03-01

    Full Text Available O trabalho foi conduzido em casa de vegetação, da UNESP em Jaboticabal, de maio a junho de 2001, com o objetivo de avaliar o desempenho da rúcula, cultivar Cultivada, sob diferentes concentrações de cobre na solução nutritiva, em cultivo hidropônico. O delineamento utilizado foi inteiramente casualizado com quatro repetições e quatro tratamentos: 0; 0,036; 0,072 e 0,108 mgL-1 de Cu adicionado à solução nutritiva, na forma de sulfato de cobre. Após 30 dias do transplantio, 150 plantas foram colhidas ao acaso em cada parcela, para análise da matéria seca e dos teores de Cu, Fe, Zn e Mn na parte aérea das plantas. Foi observado sintoma visual de deficiência de Cu apenas no tratamento sem adição de cobre, com forte redução no tamanho das plantas. A produção de matéria seca da parte aérea foi significativamente influenciada pelo aumento das concentrações de Cu. A máxima produção e 95% da máxima foram obtidas, respectivamente, com 0,108 mgL-1 e 0,064 mgL-1 de cobre. Os teores de Cu e Mn na parte aérea aumentaram com as concentrações de Cu na solução nutritiva.The response of roquette cv. Cultivada, to different copper concentrations in the nutrient solution was evaluated. The experimental design was completely randomized, with four treatments (0; 0.036; 0.072 and 0.108 mgL-1 of copper added to the nutrient solution and four replications. 30 days after transplanting, 150 plants were collected at random in order to analyse the concentrations of Cu, Fe, Zn and Mn in the dry matter of the aerial part. Symptoms of deficiency were observed in the treatment without copper, presenting strong reduction in the plant size. The dry matter yield was significantly influenced by the increasing concentrations of Cu, with maximum production and 95% of maximum yield was obtained respectively with 0.108 and 0.064 mgL-1 of Cu in the nutritive solution. The concentration of Cu and Mn in the aerial part increased with increasing

  3. Relaxation Process of Excitonic Molecules in CuCl under the Two-Photon Resonant Excitation. II. Transverse Relaxation

    Science.gov (United States)

    Itoh, Tadashi; Katohno, Takashi; Kirihara, Toshio; Ueta, Masayasu

    1984-02-01

    Under the off-resonant excitation at the slightly higher energy side of the giant two-photon absorption band (GTA) for the direct generation of excitonic molecules (EM) in CuCl, new narrow emission bands designated as XT and XL have been found in the energy region of the MT and ML broad bands, respectively. Their photon energies increase with the decrease of the pump photon energy from the higher-energy side of the resonance and finally, at the on-resonant excitation, their bands merge into MT0 and ML0 bands, respectively, previously reported by Mita et al. Based on the detailed studies on these bands, it is found that there exists a certain kind of transverse relaxation process which acts on the EM just after their generation by the GTA and brings about the X emission as a hot luminescence.

  4. Insights into water coordination associated with the Cu(II)/Cu(I) electron transfer at a biomimetic Cu centre.

    Science.gov (United States)

    Porras Gutiérrez, Ana Gabriela; Zeitouny, Joceline; Gomila, Antoine; Douziech, Bénédicte; Cosquer, Nathalie; Conan, Françoise; Reinaud, Olivia; Hapiot, Philippe; Le Mest, Yves; Lagrost, Corinne; Le Poul, Nicolas

    2014-05-01

    The coordination properties of the biomimetic complex [Cu(TMPA)(H2O)](CF3SO3)2 (TMPA = tris(2-pyridylmethyl)amine) have been investigated by electrochemistry combined with UV-Vis and EPR spectroscopy in different non-coordinating media including imidazolium-based room-temperature ionic liquids, for different water contents. The solid-state X-ray diffraction analysis of the complex shows that the cupric centre lies in a N4O coordination environment with a nearly perfect trigonal bipyramidal geometry (TBP), the water ligand being axially coordinated to Cu(II). In solution, the coordination geometry of the complex remains TBP in all media. Neither the triflate ion nor the anions of the ionic liquids were found to coordinate the copper centre. Cyclic voltammetry in all media shows that the decoordination of the water molecule occurs upon monoelectronic reduction of the Cu(II) complex. Back-coordination of the water ligand at the cuprous state can be detected by increasing the water content and/or decreasing the timescale of the experiment. Numerical simulations of the voltammograms allow the determination of kinetics and thermodynamics for the water association-dissociation mechanism. The resulting data suggest that (i) the binding/unbinding of water at the Cu(I) redox state is relatively slow and equilibrated in all media, and (ii) the binding of water at Cu(I) is somewhat faster in the ionic liquids than in the non-coordinating solvents, while the decoordination process is weakly sensitive to the nature of the solvents. These results suggest that ionic liquids favour water exchange without interfering with the coordination sphere of the metal centre. This makes them promising media for studying host-guest reactions with biomimetic complexes.

  5. Mesoscale organization of CuO nanoslices: Formation of sphere

    Indian Academy of Sciences (India)

    Jun Wang; Shunxiao Zhang; Zhanshuang Li; Jia You; Piaoping Yang; Xiaoyan Jing; Milin Zhang

    2008-04-01

    The nanocrystalline CuO powders were prepared by precipitation method using Cu(NO$_{3})_{2}$ as copper raw material, water and ethanol as dispersants, and NaOH and ammonia solution as precipitates. The structure, particle size and morphology of resulting CuO powders were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The mechanism of CuO formation was discussed.

  6. Narcisismo e corporeidade em Freud

    OpenAIRE

    Gaio, Fernando Moysés

    2015-01-01

    A indagação deste estudo parte da constatação de que Freud atribui uma origem narcísica ao eu, e, ao mesmo tempo, refere-se ao eu como um eu corporal. Essa afirmação coloca em questão a relação do narcisismo com a corporeidade, que não é explicitamente tematizada em sua obra, aparecendo sempre de forma dispersa ao longo de seu desenvolvimento. As referências a respeito do tema do narcisismo em suas obras revelam, além disso, uma contínua evolução do seu conceito. Neste estudo, acompanha-se pr...

  7. Divisão de trabalho em cuidados à prole em Sicalis flaveola (Linnaeus, 1766) (Passeriformes, Emberizidae), em cativeiro

    OpenAIRE

    Luiz Octavio Marcondes-Machado

    1988-01-01

    São relatadas observações relativas à divisão de trabalho em cuidados à prole em Sicalis flaveola brasiliensis (Gmelin) e S. f. pelzelni (Sclater), em condições de cativeiro.Observations relating to the division of labour for young care in Sicalis flaveola brasiliensis (Gmelin) and S. f. pelzelni (Sclater), in captivity, are presented.

  8. Coordination equilibria in the complex formation of guanylurea with CuII: Formation and stability of binary CuII-guanylurea and ternary CuII-guanylurea-glycinate complexes

    Indian Academy of Sciences (India)

    Tannistha Roy Barman; G N Mukherjee

    2008-07-01

    Combined pH-metric and spectrophotometric investigations on the complex formation equilibria of CuII with guanylurea (H$_{2}^{1}$NC(=O) 2NH.C(=3NH) 4NH2), hereafter, GuH, in the absence and in the presence of glycine (GlyH), in aqueous solution indicates variety of binary and mixed-ligand complexes: Cu(Gu)+, Cu(Gu)(OH); Cu(Gu)2, Cu(Gu-H)(Gu)-, Cu(Gu-H)$_{2}^{2-}$, Cu(Gu-H)(Gu-2H)3-; Cu(Gly)+, Cu(Gly) (OH); Cu(Gly)(Gu); Cu(Gly)(Gu-H)-, Cu(Gly)(Gu-2H)2-; (Gly)Cu(Gu)Cu(Gly)+, (Gly)Cu(Gu-H)Cu(Gly) and (Gly)Cu(Gu-2H)Cu(Gly)-. At pH < 6, guanylurea anion (Gu-) acts as a [(C=O), 3N-] or [=1NH, 3N-] bidentate ligand and above pH 7 it is transformed through a coordination equilibrium into a (=1N-, =3N-) bidentate ligand, similar to biguanide dianion. Occurrence of dinuclear complex species, (Gly) Cu(Gu)Cu(Gly)+, in the complexation equilibria, indicates bridging double bidentate [(1NH2, 3N-), (C=O, 4NH2)] and/or [(1NH2, 4NH2), (C=O, 3N-)] chelation by Gu- ion in an isomeric equilibrium. Above pH 6.5, the dinuclear complex decomposes mostly to the mononuclear species, Cu(Gly)(OH) and Cu(Gu)(OH) and only partly deprotonates to (Gly)Cu(Gu-H)Cu(Gly) and (Gly)Cu(Gu-2H)Cu(Gly)-. Electronic spectral shifts, with change of pH have been correlated with the possible modes of coordination of guanylurea species.

  9. Cu(II) promotes amyloid pore formation

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Hangyu, E-mail: hangyuz@uw.edu [Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907 (United States); Rochet, Jean-Christophe [Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907 (United States); Stanciu, Lia A. [Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907 (United States); School of Materials Engineering, Purdue University, West Lafayette, IN 47907 (United States)

    2015-08-14

    The aggregation of α-synuclein is associated with dopamine neuron death in Parkinson's disease. There is controversy in the field over the question of which species of the aggregates, fibrils or protofibrils, are toxic. Moreover, compelling evidence suggested the exposure to heavy metals to be a risk of PD. Nevertheless, the mechanism of metal ions in promoting PD remains unclear. In this research, we investigated the structural basis of Cu(II) induced aggregation of α-synuclein. Using transmission electron microscopy experiments, Cu(II) was found to promote in vitro aggregation of α-synuclein by facilitating annular protofibril formation rather than fibril formation. Furthermore, neuroprotective baicalein disaggregated annular protofibrils accompanied by considerable decrease of β-sheet content. These results strongly support the hypothesis that annular protofibrils are the toxic species, rather than fibrils, thereby inspiring us to search novel therapeutic strategies for the suppression of the toxic annular protofibril formation. - Highlights: • Cu(II) promoted the annular protofibril formation of α-synuclein in vitro. • Cu(II) postponed the in vitro fibrillization of α-synuclein. • Neuroprotective baicalein disaggregated annular protofibrils.

  10. Superconductivity in Zigzag CuO Chains

    Energy Technology Data Exchange (ETDEWEB)

    Berg, E.

    2010-04-06

    Superconductivity has recently been discovered in Pr{sub 2}Ba{sub 4}Cu{sub 7}O{sub 15-{delta}} with a maximum T{sub c} of about 15K. Since the CuO planes in this material are believed to be insulating, it has been proposed that the superconductivity occurs in the double (or zigzag) CuO chain layer. On phenomenological grounds we propose a theoretical interpretation of the experimental results in terms of a new phase for the zigzag chain, labelled by C{sub 1}S{sub 3/2}. This phase has a gap in the relative charge mode and a partial gap in the relative spin mode. It has gapless uniform charge and spin excitations and can have a divergent superconducting susceptibility, even for repulsive interactions. A microscopic model for the zigzag CuO chain is proposed, and on the basis of density matrix renormalization group (DMRG) and bosonization studies, we adduce evidence that supports our proposal.

  11. Surface structure of AU3Cu(001)

    DEFF Research Database (Denmark)

    Eckstein, G.A.; Maupai, S.; Dakkouri, A.S.

    1999-01-01

    The surface morphology, composition, and structure of Au3Cu(001) as determined by scanning tunneling microscopy and surface x-ray diffraction are presented. Atomic resolution STM images reveal distinctive geometric features. The analysis of the surface x-ray diffraction data provides clear evidence...... for the surface structure. [S0163-1829(99)04535-X]....

  12. Objetos mediadores em museus

    Directory of Open Access Journals (Sweden)

    Inês Ferreira

    2015-02-01

    Full Text Available Um museu participativo incentiva a que a experiência da visita seja criativa e pessoal. Facilita a participação biográfica do visitante - com a sua experiência, conhecimento e interesses. Muitas exposições, porém, não promovem esse envolvimento pessoal. Neste artigo apresentamos uma revisão da literatura que indicia que a mediação com objetos mediadores facilita o envolvimento pessoal, a construção de conhecimento e a criatividade. O problema teórico que colocamos é se os museus mais tradicionais se podem abrir à participação e, neste contexto, o nosso objetivo é perceber que papel podem ter os objetos mediadores nesse processo. Discutimos o recurso a objetos mediadores como forma de adicionar múltiplos níveis de relação e modos de ver, potencial que consideramos subaproveitado em muitos museus. Começamos por apresentar o museu como espaço potencialmente participativo, que convida a um envolvimento ativo e crítico – ativo, porque o visitante é desafiado a fazer coisas; crítico, porque é estimulado a pensar, optar, discutir e refletir. Discutimos depois diferentes formas de usar objetos mediadores para incentivar o visitante a um envolvimento com os artefactos, recorrendo à memória, experiência, conhecimento e sentimentos. A participação biográfica potencia o cruzamento entre o mundo interior do visitante e os artefactos e conteúdos do museu. Esse espaço de cruzamento - inbetween - é o espaço da construção de conhecimento. Apresentamos diversas formas de um museu, mesmo não sendo interativo, se tornar mais criativo e participativo, o que pode contribuir para uma mudança nas práticas dos museus, nomeadamente na montagem e remodelação de exposições permanentes.

  13. Óleo de eucalipto e Pisolithus microcarpus no crescimento de bracatinga em solo contaminado por cobre

    Directory of Open Access Journals (Sweden)

    Alex Dellai

    2014-09-01

    Full Text Available As áreas de mineração de cobre podem apresentar teores elevados disponíveis deste nutriente no solo afetando o desenvolvimento vegetal. O objetivo do trabalho foi avaliar o efeito do óleo essencial de eucalipto na associação ectomicorrizica com o fungo Pisolithus microcarpus em mudas de bracatinga e seu comportamento em solo contaminado por cobre. O experimento foi conduzido em delineamento inteiramente casualizado em arranjo fatorial (4 x 5 sendo quatro formas de inoculação (testemunha, óleo, fungo e óleo + fungo e cinco doses de cobre (nível natural do solo, 60, 120, 180 e 240 mg de Cu kg-1 de solo com cinco repetições. Avaliaram-se a altura de plantas (cm, diâmetro do colo (mm, massa seca da parte aérea e radicular (g, comprimento radicular (cm, área superficial específica (cm², relação altura/diâmetro do colo e índice de qualidade de Dickson. Verificou-se que a utilização de 40 μL L-1 de óleo essencial de eucalipto aumenta a altura das mudas de bracatinga em solo com adição de 180 mg de Cu kg-1 de solo. Não há efeito da inoculação de Pisolithus microcarpus no crescimento das mudas de bracatinga em solo contaminado com cobre. As doses de cobre reduzem a massa seca da parte aérea e radicular das mudas.

  14. Formamido-Diterpenes from the South China Sea Sponge <em>Acanthella cavernosaem>

    Directory of Open Access Journals (Sweden)

    Bao-Hua Zhang

    2012-07-01

    Full Text Available Seven new formamido-diterpenes, cavernenes A–D (14, kalihinenes E and F (56, and kalihipyran C (7, together with five known compounds (812, were isolated from the South China Sea sponge <em>Acanthella cavernosaem>. Structures were established using IR, HRESIMS, 1D and 2D NMR, and single X-ray diffraction techniques. The isolated compounds were assessed for their cytotoxicity against a small panel of human cancer cell lines (HCT-116, A549, HeLa, QGY-7701, and MDA-MB-231 with IC50 values in the range of 6–18 μM. In addition, compound 9 showed weak antifungal activity against <em>Trichophyton rubrumem> and <em>Microsporum gypseumem> with MIC values of 8 and 32 μg/mL, respectively, compound 10 displayed weak antifungal activity against fungi <em>Candida albicansem>, <em>C>ryptococcus neoformansem>, <em>T. rubrumem>, and<em> M. gypseum em>with MIC values of 8, 8, 4, and 8 μg/mL, respectively.

  15. Operations and Performance of RHIC as a Cu-Cu Collider

    CERN Document Server

    Pilat, Fulvia Caterina; Bai, Mei; Barton, Donald; Beebe-Wang, Joanne; Blaskiewicz, Michael; Brennan, Joseph M; Bruno, Donald; Cameron, Peter; Connolly, Roger; De Long, Joseph; Drees, Angelika; Fischer, Wolfram; Ganetis, George; Gardner, Chris J; Glenn, Joseph; Harvey, Margaret; Hayes, Thomas; Hseuh Hsiao Chaun; Huang, Haixin; Ingrassia, Peter; Iriso, Ubaldo; Lee, Roger C; Litvinenko, Vladimir N; Luo, Yun; MacKay, William W; Marr, Gregory J; Marusic, Al; Michnoff, Robert; Montag, Christoph; Morris, John; Nicoletti, Tony; Oerter, Brian; Ptitsyn, Vadim; Roser, Thomas; Russo, Thomas; Sandberg, Jon; Satogata, Todd; Schultheiss, Carl; Tepikian, Steven; Tomas, Rogelio; Trbojevic, Dejan; Tsoupas, Nicholaos; Tuozzolo, Joseph; Vetter, Kurt; Zaltsman, Alex; Zeno, Keith; Zhang, S Y; Zhang, Wu

    2005-01-01

    The 5th year of RHIC operations, started in November 2004 and expected to last till June 2005, consists of a physics run with Cu-Cu collisions at 100 GeV/u followed by one with polarized protons at 100 GeV. We will address here overall performance of the RHIC complex used for the first time as a Cu-Cu collider, and compare it with previous operational experience with Au, PP and asymmetric d-Au collisions. We will also discuss operational improvements, such as a ?* squeeze to 85cm in the high luminosity interaction regions from the design value of 1m, system improvements and machine performance limitations, such as vacuum pressure rise, intra-beam scattering, and beam beam interaction.

  16. Pressure dependence of the Cu magnetic order in RBa2Cu3O6+x

    Science.gov (United States)

    Lynn, J. W.; Li, W.-H.; Trevino, S. F.; Fisk, Z.

    1989-09-01

    Neutron-diffraction measurements have been carried out as a function of hydrostatic pressure to study the magnetic order of the Cu spins in NdBa2Cu3O6.35 and NdBa2Cu3O6.1. In the high-temperature phase, where the Cu planes order antiferromagnetically, we find that the Néel temperature TN1 is very strongly dependent on pressure, increasing at the rate of ~23 K/kbar. We attribute this phenomenal sensitivity to the two-dimensional-like behavior of this magnetic system. In the low-temperature phase, which is associated with magnetic ordering of the chains, only a small change in the ordering temperature TN2 is observed.

  17. Strength and reliability of low temperature transient liquid phase bonded Cu-Sn-Cu interconnects

    DEFF Research Database (Denmark)

    Brincker, Mads; Söhl, Stefan; Eisele, Ronald

    2017-01-01

    as a potential technology that could enable the realization of stacks with better thermal performance and reliability than those can be achieved using conventional soldering techniques. Low temperature TLP bonded CuSnCu samples are fabricated, and the strength of the achieved bonds is measured by shear testing......As power electronic devices have tendencies to operate at higher temperatures and current densities, the demand for reliable and efficient packaging technologies are ever increasing. This paper reports the studies on application of transient liquid phase (TLP) bonding of CuSnCu systems...... for achieving a strong and high temperature resistant bond. Finally, initial results from a thermal cycling test are presented and it is concluded that the achieved TLP bonding is a promising candidate for the fabrication of reliable interconnects in power electronics....

  18. Metastable Demixing of Supercooled Cu-Co and Cu-Fe Alloys in an Oxide Flux

    Science.gov (United States)

    Li, D.; Robinson, M. B.; Rathz, T. J.; Williams, G.

    1998-01-01

    A systematic study on the liquid separation in supercooled Cu-Co and Cu-Fe alloys was performed using a melt fluxing which permits high supercooling to be achieved. Moreover, this method renders it possible to directly measure binodal temperatures and establish metastable liquid miscibility gap (LMG). All phase-separated samples at compositions ranging from 10 to 80 wt pct Co or to 83 wt pct Fe were found to exhibit droplet-shaped morphologies, in spite of various droplet distributions. Uniformly dispersed microstructures were obtained as the minority component was less than 20 vol.%; while beyond this percentage, serious coarsening was brought about. Calculations of the miscibility gap in the Cu-Co system and Stokes movement velocity of Co and Fe droplets in Cu matrix were made to analyze the experimental results.

  19. Order twins in (111)-evaporated thin films of CuAu I. [Cu-Au

    Energy Technology Data Exchange (ETDEWEB)

    Zimmerman, R.; Broitman, E. (Dept. de Fisica, Univ. de Buenos Aires (Argentina)); Harriague, S.; Terlisky, S. (Comision Nacional de Energia Atomica, Buenos Aires (Argentina))

    1990-10-15

    The structure of evaporated CuAu I films in (111) orientation was studied by electron transmission and diffraction microscopy. The single-crystal films of Cu-Au alloy were prepared by vacuum evaporation and CuAu I ordered alloy was obtained by heating the disordered f.c.c. alloy to a temperature of 350deg C for 1 h. The electron micrograph revealed the presence of an intricate pattern of antiphase domain boundaries and the presence of twin lamellae. No microtwinning was observed. The CuAu I films exhibit a complex diffraction pattern. The geometry of the expected (111) reciprocal lattice plane has been calculated and described in detail. Extra reflections were identified as {l brace}101{r brace} twin spots and double-diffraction spots which originated from the twins. (orig.).

  20. Controlled synthesis of CuO nanostructures on Cu foil, rod and grid

    Energy Technology Data Exchange (ETDEWEB)

    Vanithakumari, S.C.; Shinde, S.L. [Materials Research Centre, Indian Institute of Science, C.V. Raman Avenue, Malleswaram, Bangalore 560012, Karnataka (India); Nanda, K.K., E-mail: nanda@mrc.iisc.ernet.in [Materials Research Centre, Indian Institute of Science, C.V. Raman Avenue, Malleswaram, Bangalore 560012, Karnataka (India)

    2011-05-15

    CuO nanowires are synthesized by heating Cu foil, rod and grid in ambient without employing a catalyst or gas flow at temperatures ranging from 400 to 800 deg. C for a duration of 1-12 h. Scanning electron microscopy (SEM) investigation reveals the formation of nanowires. The structure, morphology and phase of the as-synthesized nanowires are analyzed by various techniques such as X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FTIR). It is found that these nanowires are composed of CuO phase and the underlying film is of Cu{sub 2}O. A systematic study is carried out to find the possibilities for the transformation of one phase to another completely. A possible growth mechanism for the nanowires is also discussed.

  1. OPERATIONS AND PERFORMANCE OF RHIC AS A CU-CU COLLIDER.

    Energy Technology Data Exchange (ETDEWEB)

    PILAT, R.; AHRENS, L.; BAI, M.; BARTON, D.S.; ET AL.

    2005-05-16

    The 5th year of RHIC operations, started in November 2004 and expected to last till June 2005, consists of a physics run with Cu-Cu collisions at 100 GeV/u followed by one with polarized protons (pp) at 100 GeV [l]. We will address here the overall performance of the RHIC complex used for the first time as a Cu-Cu collider, and compare it with previous operational experience with Au, PP and asymmetric d-Au collisions. We will also discuss operational improvements, such as a {beta}* squeeze to 85cm in the high luminosity interaction regions from the design value of 1m, system improvements, machine performance and limitations, and address reliability and uptime issues.

  2. Structural and magnetic properties of epitaxial Fe/Cu multilayers

    Energy Technology Data Exchange (ETDEWEB)

    Harada, Y. E-mail: t5101008@iwate-u.ac.jp; Nakanishi, Y.; Yoshimoto, N.; Yamaguchi, A.; Nakamura, M.; Yoshizawa, M

    2004-05-01

    We have grown FCC-Fe/Cu multilayers by molecular beam epitaxy method. The structural and magnetic properties were studied by RHEED, XRD and magnetoresistance measurement (MR). The RHEED images confirmed that Fe/Cu multilayers were epitaxially grown on Cu(1 0 0). Furthermore, a clear negative MR was observed. The buffer layer condition for MR effect will be discussed.

  3. Ferromagnetism in CuO-ZnO multilayers

    Science.gov (United States)

    Chandran, Sudakar; Kirby, B. J.; Padmanabhan, K.; Lawes, G.; Naik, R.; Kumar, Sanjiv; Naik, V. M.

    2008-03-01

    The magnetic properties of CuO-ZnO heterostructures are examined to elucidate the origin of the ferromagnetic signature in Cu doped ZnO. The CuO and ZnO layer thickness varied from 15 nm to 350 nm, and we observed no significant diffusion of either Cu^2+ in the ZnO layers or of Zn^2+ in the CuO layers using Rutherford backscattering spectrometry. Bulk magnetization measurements established that the multilayers exhibit a ferromagnetic moment at room temperature, with a saturation magnetization (˜2-5 emu/cc of CuO) that depends on the CuO size, but not the CuO-ZnO interfacial area. Polarized neutron reflection studies suggest that the ferromagnetism arises from the CuO layers, and not from the interdiffusion of CuO and ZnO. These results indicate that the ferromagnetism in these multicomponent structures arises from the uncompensated surface spins of CuO nanoparticles in the layer rather than from regions of interdiffusing ZnO and CuO.

  4. Two different cationic positions in Cu-SSZ-13?

    Science.gov (United States)

    Hun Kwak, Ja; Zhu, Haiyang; Lee, Jong H; Peden, Charles H F; Szanyi, János

    2012-05-16

    H(2)-TPR and FTIR were used to characterize the nature of the Cu ions present in the Cu-SSZ-13 zeolite at different ion exchange levels. The results obtained are consistent with the presence of Cu ions at two distinct cationic positions in the SSZ-13 framework.

  5. Two different cationic positions in Cu-SSZ-13?

    Energy Technology Data Exchange (ETDEWEB)

    Kwak, Ja Hun; Zhu, Haiyang; Lee, Jong H.; Peden, Charles HF; Szanyi, Janos

    2012-04-18

    H2-TPR and FTIR were used to characterize the Cu ions present in Cu-SSZ-13 zeolite at different ion exchange levels. The results obtained are consistent with the presence of Cu ions in two distinct cationic positions of the SSZ-13 framework.

  6. Microstructure of directionally solidified Cu-Cr composites

    Institute of Scientific and Technical Information of China (English)

    毕晓勤; 李金山; 胡锐; 耿兴国; 朱琦; 傅恒志

    2004-01-01

    Cu-Cr composites were prepared by self-made directional solidification equipment with the high temperature gradient and double-zone heating. The microstructural evolution was investigated during the directional solidification with the different solidification rate for Cu-1.0%Cr, Cu-1.7%Cr and Cu-5.6%Cr alloys, respectively. It is shown that for the hypoeutectic Cu-1.0%Cr alloy, the general microstructures consist of primary α(Cu) phase and the rod-like or needle-like (α+β) eutectics, and for the hypereutectic Cu-1. 7%Cr and Cu-5.6%Cr alloys, α(Cu)phase, primary β(Cr) phase and (α+β) eutectics coexist. With the increase of the solidification rate, the morphology evolution of every phase is that, 1st cellular(dendrite) of α(Cu) phase thins and cellular(dendrite) spacing shortens gradually, (α+β) eutectics set in α(Cu) cellular or dendrite, and primary β(Cr) phase distributes unevenly on α (Cu) matrix, whose morphology undergoes the change from dendrite to particle.

  7. Electromigration of Sn-3Ag-0.5Cu and Sn-3Ag-0.5Cu-0.5Ce-0.2Zn solder joints with Au/Ni(P)/Cu and Ag/Cu pads

    Energy Technology Data Exchange (ETDEWEB)

    Lin, H.-J., E-mail: HJLin@itri.org.t [Institute of Materials Science and Engineering, National Taiwan University, 1 Roosevelt St. Sec. 4, Taipei 106, Taiwan (China); Industrial Technology Research Institute, Mechanical and Systems Research Laboratories, Hsinchu 310, Taiwan (China); Lin, J.-S., E-mail: JohnnyLin@itri.org.t [Industrial Technology Research Institute, Mechanical and Systems Research Laboratories, Hsinchu 310, Taiwan (China); Department of Mechanical Engineering, Osaka University, Yamadaoka 2-1, Suita, Osaka 565-0871 (Japan); Chuang, T.-H., E-mail: tunghan@ntu.edu.t [Institute of Materials Science and Engineering, National Taiwan University, 1 Roosevelt St. Sec. 4, Taipei 106, Taiwan (China)

    2009-11-13

    It has previously been established that adding 0.2 wt.% Zn into a Sn-3Ag-0.5Cu-0.5Ce alloy improves the mechanical properties and eliminates the problem of rapid whisker growth. However, no detailed studies have been conducted on electromigration behavior of Sn-3Ag-0.5Cu-0.5Ce-0.2Zn alloy. The electromigration damage in solder joints of Sn-3Ag-0.5Cu and Sn-3Ag-0.5Cu-0.5Ce-0.2Zn with Ag/Cu pads and Au/Ni(P)/Cu pads was studied after current stressing at room temperature with an average current density of 3.1 x 10{sup 4} A/cm{sup 2}. With additions of 0.5 wt.% Ce and 0.2 wt.% Zn, the electromigration processes of Sn-Ag-Cu solder joints were accelerated due to refinement of the solder matrix when joint temperature was around 80 deg. C. Since Ni is more resistant than Cu to diffusion driven by electron flow, solder joints of both alloys (Sn-3Ag-0.5Cu and Sn-3Ag-0.5Cu-0.5Ce-0.2Zn) with Au/Ni(P)/Cu pads possess longer current-stressing lifetimes than those with Ag/Cu pads.

  8. Conduction behavior conversion for Cu-doped ZnS/n-type Si devices with different Cu contents

    Science.gov (United States)

    Ni, Wei-Shih; Lin, Yow-Jon

    2015-06-01

    Currents through Cu-doped ZnS (ZnCuS)/n-type Si structures were studied. The electrical conduction investigations suggest that the carrier transport behavior is governed by the Poole-Frenkel emission for ZnCuS/n-type Si devices having the low Cu concentration. However, the carrier transport behavior is governed by the thermionic emission for ZnCuS/n-type Si devices having the high Cu concentration. The photoluminescence result revealed that sulfur vacancy ( V S) is the origin of conduction behavior conversion. It is shown that the increased Cu concentration leads to the reduced formation probability of V S. The dependence of V S on the film composition was identified for providing a guide to control the current transport behavior of ZnCuS/n-type Si devices.

  9. MICROAGREGADOS ESTÁVEIS E RESERVA DE NUTRIENTES EM LATOSSOLO VERMELHO SOB PASTAGEM EM REGIÃO DE CERRADO STABLE MICROAGGREGATES AND NUTRIENT POOL IN OXISOL UNDER PASTURE IN SAVANNAH REGION

    Directory of Open Access Journals (Sweden)

    Maurício Paulo Ferreira Fontes

    2011-04-01

    Full Text Available

    Nutrientes preservados em microagregados podem constituir reserva importante em solos altamente intemperizados. Com o objetivo de melhor compreender a distribuição de nutrientes em microagregados contidos em frações granulométricas de 200-50 <em>u>m e 50-20 <em>u>m, de um Latossolo Vermelho distrófico típico, utilizou-se um procedimento de fracionamento físico, adaptado para o objetivo deste estudo, em conjunto com análises químicas e mineralógicas. Parte destas frações foi caracterizada como microagregados constituídos por minerais da fração argila e silte, com altos teores de macro e micronutrientes. P, Cu, Mn e Zn foram mais eficientemente acumulados nos microagregados e menos susceptíveis à remoção, pela ação do intemperismo e lixiviação, em comparação ao K e Mg. Maiores teores de C foram encontrados nos microagregados de 50-20 <em>u>m do horizonte superficial, devido à proteção física mais eficiente contra a mineralização. Os estoques de macro e micronutrientes (teores totais, nos microagregados (200-50 <em>u>m e 50-20 <em>u>m, corresponderam a 5-19% do total de nutrientes no solo, e 24-26% do total de carbono do solo esteve sequestrado nestes microagregados. Apesar da baixa capacidade de reserva destes microagregados, eles tornam-se um compartimento de alta estabilidade, com maior eficiência na função de preservar os nutrientes, frente à degradação física e ao intemperismo e lixiviação.


    PALAVRAS-CHAVE: Agregados do solo; fracionamento físico; macronutrientes; micronutrientes; estoque de matéria orgânica.

    Nutrients preserved in microaggregates are an important fraction of the pool of nutrients in

  10. Cluster de ventiladores em Catanduva.

    Directory of Open Access Journals (Sweden)

    Luciana M. Onusic

    2005-04-01

    Full Text Available Este trabalho apresenta os resultados de um levantamento feito na cidade de Catanduva sobre a indústria de ventiladores nela instalada. É, inicialmente, apresentado o conceito de cluster, para, em seguida, serem apresentadas as características do setor de ventiladores de Catanduva, fazendo uma comparação desse setor com o conceito de cluster. Diversos aspectos mostram o interesse em considerar o setor como um cluster e são feitas sugestões para seu aprimoramento.

  11. Hiperplasia gengival medicamentosa em Odontopediatria

    OpenAIRE

    Lourenço, Lília Carla Carvalho

    2013-01-01

    Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Medicina Dentária Um periodonto saudável com os seus constituintes é uma parte fundamental para uma boa saúde oral em qualquer género e idade. As crianças também são afetadas por patologias periodontais, nomeadamente a hiperplasia gengival; esta pode ser de variados tipos e etiologias, sendo um desses tipos a hiperplasia gengival medicamentosa (HGM) p...

  12. Alegoria redimida em Walter Benjamin

    OpenAIRE

    Anderson Borges

    2012-01-01

    Este estudo apresenta o decurso da alegoria na obra benjaminiana circunscrevendo a investigação a três momentos principais: o livro Origem do drama barroco alemão, em que a alegoria é resgatada do esquecimento e, considerando a significativa expressividade do luto (Trauer) e da melancolia na constituição do teatro barroco, ganha um lugar cativo no âmbito estético, bem como, além disso, funciona como representação da história na perspectiva de literatos do século XVII; Rua de mão única, em que...

  13. Treino cognitivo em idosos institucionalizados

    OpenAIRE

    Ferreira, Sara Melissa

    2012-01-01

    Face ao crescimento e longevidade da população idosa na sociedade atual torna-se cada vez mais necessário criar estratégias em prol de um Envelhecimento Ativo, ambicionando mais qualidade nos anos vividos. Sabe-se que ao longo do desenvolvimento humano existem perdas e ganhos. Estudos documentam declínio da capacidade da memória em indivíduos de idade avançada. No entanto, existem inúmeras evidências científicas da plasticidade cerebral que fundamentam a intervenção cognitiva através de Progr...

  14. Dissolution behavior of Cu in Cu-Ag and Cu-P brazing alloys using weld brazing%溶解钎焊时Cu在Cu-Ag及Cu-P合金钎料中的溶解行为

    Institute of Scientific and Technical Information of China (English)

    李一楠; 王长文; 彭子龙; 闫久春; 刘雪松

    2011-01-01

    研究溶解钎焊条件下母材Cu在Cu-Ag及Cu-P合金钎料中的溶解行为.测量了在800~920℃的温度范围内铜箔在Cu-P和Cu-Ag合金中的溶解厚度.推导并计算出Cu在这两种合金钎料中的溶解速度常数存在如下关系:kCu-p(T)=10kCu-A(T).结果表明,采用溶解钎焊工艺时在相同条件下液态Cu-P合金对母材Cu的溶解量大于Cu-Ag合金的.由于溶解钎焊工艺在一个热循环内具有反应时间短和温度变化快的特点,因此Cu在液态钎料中快的溶解反应速度是实现溶解钎焊的根本原因.同时,P元素与Ag元素相比具有加速溶解母材的作用,是实现溶解钎焊必不可少的合金元素.研究了合金元素的添加对焊接接头力学性能的影响,提出了获得良好力学性能的钎料成分设计原则.%The dissolution behavior of base metal Cu in the Cu-Ag and Cu-P brazing alloys using weld brazing was researched.The thickness loss of Cu foil in contact with Cu-P and Cu-Ag alloys at 800-920 ℃ was measured.And the dissolution rate constants in both alloys were calculated as the following relation:kcu-p(T)=1 0kCu.Ag(T),which explains the special phenomenon that the dissolving amount of copper in Cu-P liquid alloys is larger than that in Cu-Ag alloys under the same condition.As weld brazing has its own characteristics of short reaction time and quick temperature variation in one thermal cycle,the quick dissolution rate of copper in filler metals is the main reason to achieve weld brazing.It can be concluded that element P is indispensable in filler metals compared with element Ag as the function of accelerating dissolution during weld brazing.Finally,the influences of the addition of alloy element on mechanical performance of the welding joints were studied and the design principles of filler metals for weld brazing were proposed to achieve good mechanical performance.

  15. Adaptabilidade e estabilidade em aveia em ambientes estratificados

    Directory of Open Access Journals (Sweden)

    Bertan Ivandro

    2005-01-01

    Full Text Available Vinte cultivares de aveia (Avena sativa L. foram avaliados para rendimento de grãos nas safras agrícolas de 2001 e 2002 em nove locais dos estados do Paraná, Rio Grande do Sul e São Paulo, com o objetivo de avaliar as estimativas dos componentes de adaptabilidade e estabilidade do rendimento de grãos em ambientes favoráveis e desfavoráveis em presença e ausência de aplicação de fungicida. Foi empregada a metodologia de EBERHART & RUSSELL (1966. A presença de significância para anos, genótipos, fungicidas e locais, indicou comportamento diferencial de genótipos frente às variações de ambiente e a aplicação de fungicida, nas condições de ambientes favoráveis e desfavoráveis. A aplicação de fungicida e o favorecimento do ambiente de cultivo afetaram intensamente os parâmetros de adaptabilidade (b1 e estabilidade (s²d i, indicando que estas estimativas devam ser realizadas em ambientes estratificados, apesar de nenhuma constituição genética ter evidenciado o biótipo ideal, conforme preconizado pelo modelo adotado.

  16. Reorientable dipolar CuCa antisite and anomalous screening in CaCu3Ti4O12

    Science.gov (United States)

    Delugas, Pietro; Alippi, Paola; Fiorentini, Vincenzo; Raineri, Vito

    2010-02-01

    Based on first-principles calculations, we show that the abundant CuCa antisite defect contributes sizably to dielectric screening in single-crystal CaCu3Ti4O12 . CuCa has a multi-minimum off-center equilibrium configuration, whereby it possesses a large and easily reorientable dipole moment. The low-temperature and frequency cut-off behavior of CuCa -induced response is consistent with experiment.

  17. Polymeric Graphitic Carbon Nitride Doped with CuO Dispersed on Dealuminated Clinoptilolite (CuO/HCP): Synthesis and Characterisation

    OpenAIRE

    Saheed Olalekan Sanni; Omoruyi Gold Idemudia

    2015-01-01

    CuO dispersed on dealuminated clinoptilolite (CuO/HCP) and further doped with polymeric graphitic carbon nitride (CuO/HCP-g-C3N4) was synthesized through 2 facile routes: precipitation method for CuO/HCP and impregnation through ultrasonication method for the hybrid composite material. The hybrid composite material crystalline phase, surface morphology, and structural and thermal properties were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-r...

  18. Low Diversity Bacterial Community and the Trapping Activity of Metabolites from Cultivable Bacteria Species in the Female Reproductive System of the Oriental Fruit Fly, <em>Bactrocera dorsalisem> Hendel (Diptera: Tephritidae

    Directory of Open Access Journals (Sweden)

    Hongyu Zhang

    2012-05-01

    Full Text Available Our goal was to identify the bacteria inhabiting the reproductive system of the female oriental fruit fly, <em>Bactrocera dorsalisem> (Hendel, and evaluate the chemotaxis of <em>B>. <em>dorsalis> to the metabolites produced by the bacteria. Based on 16S rRNA-based polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE, 18 operational taxonomic units (OTUs were assigned to the five bacterial classes <em>Betaproteobacteria>, <em>Alphaproteobacteria>, <em>Gammaproteobacteria>, <em>Bacilli> and <em>Actinobacteria>. Nine OTUs were assigned to <em>Gammaproteobacteria>, which was the most highly represented class. <em>Enterobacteriaceae> constituted the dominant family, and within this family, three genera and five species were identified, including <em>Enterobacter sakazakiiem>, <em>Klebsiella> <em>oxytoca>, <em>Klebsiella> <em>pneumoniae,> Raoultellaem> <em>terrigena em>and <em>Enterobacter> <em>amnigenus>. In this set, the first two species were the dominant components, and the latter three species were the minor ones. Finally, we found that the metabolites produced by <em>R.> terrigenaem>, <em>K. oxytocaem> and <em>K.> pneumoniae em>were attractive to the <em>B.> dorsalisem> adults, and in field studies, <em>B.> dorsalisem> adults were most attracted to <em>K.> oxytocaem>. Collectively, our results suggest that the female reproductive system plays an important role in the transfer of enterobacteria from the gut to fruit. Our data may prompt the development of a female-targeted population control strategy for this fly.

  19. Vibrations of tetrahedral Co and Cu clusters on a Cu(111) surface

    Energy Technology Data Exchange (ETDEWEB)

    Borisova, Svetlana D.; Rusina, Galina G. [Institute of Strength Physics and Materials Science SB RAS, pr. Akademichesky 2/4, 634021 Tomsk (Russian Federation); Eremeev, Sergey V. [Institute of Strength Physics and Materials Science SB RAS, pr. Akademichesky 2/4, 634021 Tomsk (Russian Federation); Tomsk State University, pr. Lenina 36, 634050 Tomsk (Russian Federation); Donostia International Physics Center (DIPC), Paseo Manuel de Lardizabal, 4, 20018 San Sebastian/Donostia (Spain); Chulkov, Evgueni V. [Donostia International Physics Center (DIPC), Paseo Manuel de Lardizabal, 4, 20018 San Sebastian/Donostia (Spain); Depto. de Fisica de Materiales and Centro de Fisica de Materiales - CFM (CSIS-UPV/EHU), Facultad de Ciencias Quimicas, Universidad del Pais Vasco/Euskal Herriko Unibertsitatea, Apdo. 1072, 20018 San Sebastian/Donostia (Spain)

    2010-11-15

    Vibrational properties of tetrahedral clusters of Cu and Co on the Cu(111) surface are studied by using interatomic interaction potentials constructed within tight-binding second moment approximation. It was shown that interaction of the Co{sub 4} and Cu{sub 4} clusters with the substrate leads to arising of frustrated translation and frustrated rotation in-plane polarized vibrational modes localized on the cluster atoms. The vibrational modes of the free Cu{sub 4} cluster upon its adsorption on the Cu(111) surface mix with Cu bulk phonons and become almost delocalized. Contrary to that, in the Co{sub 4} cluster on the surface the high frequency modes remain strongly localized and mixed with the nearest neighbor atoms vibrations. The highest frequency vibration of the Co{sub 4} cluster splits due to different interaction with certain groups of nearest neighbor atoms (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  20. Cu-capped surface alloys of Pt/Cu left brace 100 right brace

    CERN Document Server

    Alshamaileh, E; Wander, A

    2003-01-01

    The room-temperature deposition of 0.5 monolayer (ML) Pt on Cu left brace 100 right brace followed by annealing to 525 K results in a sharp c(2 x 2) low-energy electron diffraction (LEED) pattern. The structure of this surface alloy is investigated by means of symmetrized automated tensor low-energy electron diffraction (SATLEED) analysis and ab initio plane wave density functional calculations. The results are then compared with those for the similar system 0.5 ML Pd/Cu left brace 100 right brace. SATLEED results for the Pt/Cu left brace 100 right brace show that it consists of an ordered c(2 x 2) Cu-Pt second layer alloy capped with a pure Cu first layer. The first and second interlayer spacings are found to be expanded by +5.1 +- 1.7 and +3.5 +- 1.7% respectively (relative to the bulk Cu interlayer spacing of 1.807 A) due to the insertion of the 8% larger Pt atoms into the second layer. The ordered mixed layer is found to be rippled by 0.08 +- 0.06 A with Pt atoms rippled outwards towards the solid-vacuum ...

  1. Room Temperature Radiolytic Synthesized Cu@CuAlO2-Al2O3 Nanoparticles

    Directory of Open Access Journals (Sweden)

    Alam Abedini

    2012-09-01

    Full Text Available Colloidal Cu@CuAlO2-Al2O3 bimetallic nanoparticles were prepared by a gamma irradiation method in an aqueous system in the presence of polyvinyl pyrrolidone (PVP and isopropanol respectively as a colloidal stabilizer and scavenger of hydrogen and hydroxyl radicals. The gamma irradiation was carried out in a 60Co gamma source chamber with different doses up to 120 kGy. The formation of Cu@CuAlO2-Al2O3 nanoparticles was observed initially by the change in color of the colloidal samples from colorless to brown. Fourier transform infrared spectroscopy (FTIR confirmed the presence of bonds between polymer chains and the metal surface at all radiation doses. Results of transmission electron microscopy (TEM, energy dispersive X-ray spectrometry (EDX, and X-ray diffraction (XRD showed that Cu@CuAlO2-Al2O3 nanoparticles are in a core-shell structure. By controlling the absorbed dose and precursor concentration, nanoclusters with different particle sizes were obtained. The average particle diameter increased with increased precursor concentration and decreased with increased dose. This is due to the competition between nucleation, growth, and aggregation processes in the formation of nanoclusters during irradiation.

  2. Diffusion of Six-Atom Cu Islands on Cu(111) and Ag(111)

    Institute of Scientific and Technical Information of China (English)

    Sardar Sikandar Hayat; I.Ahmad; M.Arshad Choudhry

    2011-01-01

    Diffusion of Cu hexamer islands on Cu(111) and Ag(111) is studied using a molecular dynamics simulation technique with many-body potentials obtained from the embedded atom method. Simulations are carried out at temperatures 300, 500 and 700 K, showing that shape-changing multiple-atom processes are more helpful for the diffusion rather than concerted motion of islands. Arrhenius plots of the diffusion coefficients provide effective energy barrier values of 161.29 ± 5 meV for Cu(111) and 179.34 ± 5 meV for Ag(111) surfaces. At 700K, one pop-up atom among island atoms is observed with correlative changes in the position and shape of the lower-layer adatoms.%@@ Diffusion of Cu hexamer islands on Cu(111) and Ag(111) is studied using a molecular dynamics simulation technique with many-body potentials obtained from the embedded atom method.Simulations are carried out at temperatures 300,500 and 700 K,showing that shape-changing multiple-atom processes are more helpful for the diffusion rather than concerted motion of islands.Arrhenius plots of the diffusion coefficients provide effective energy barrier values of 161.29 ± 5 meV for Cu(111) and 179.34 ± 5 meV for Ag(111) surfaces.At 700K,one pop-up atom among island atoms is observed with correlative changes in the position and shape of the lower-layer adatoms.

  3. Reduced Cu concentration in CuAl-LPE-grown thin Si layers

    Energy Technology Data Exchange (ETDEWEB)

    Wang, T.H.; Ciszek, T.F.; Asher, S.; Reedy, R. [National Renewable Energy Lab., Golden, CO (United States)

    1995-08-01

    Cu-Al has been found to be a good solvent system to grow macroscopically smooth Si layers with thicknesses in tens of microns on cast MG-Si substrates by liquid phase epitaxy (LPE) at temperatures near 900{degrees}C. This solvent system utilizes Al to ensure good wetting between the solution and substrate by removing silicon native oxides, and employs Cu to control Al doping into the layers. Isotropic growth is achieved because of a high concentration of solute silicon in the solution and the resulting microscopically rough interface. The incorporation of Cu in the Si layers, however, was a concern since Cu is a major solution component and is generally regarded as a bad impurity for silicon devices due to its fast diffusivity and deep energy levels in the band gap. A study by Davis shows that Cu will nonetheless not degrade solar cell performance until above a level of 10{sup 17} cm{sup -3}. This threshold is expected to be even higher for thin layer silicon solar cells owing to the less stringent requirement on minority carrier diffusion length. But to ensure long term stability of solar cells, lower Cu concentrations in the thin layers are still preferred.

  4. Effects of Two Varieties of <em>Bacillus thuringiensisem> Maize on the Biology of <em>Plodia interpunctellaem>

    Directory of Open Access Journals (Sweden)

    Jean-Claude Grégoire

    2012-05-01

    Full Text Available On the market since 1996, genetically modified plants expressing an insecticidal toxin (Cry toxin stemmed from <em>Bacillus thuringiensisem> target several lepidopteran and coleopteran pests. In this study, we assessed the impact of two varieties of <em>Bt em>maize producing different toxins (Cry1Ab or Cry1Fa, respectively on the biology of a storage pest: <em>Plodia interpunctella em>(Hübner (Lepidoptera: Pyralidae. The Indianmeal moths were susceptible to both toxins but showed an escape behavior only from Cry1Fa. The weight of females issued from larvae reared on Cry1Ab increased with increasing toxin concentration, but adults of both sexes reared on Cry1Fa had decreased weight. Both toxins increased development time from egg to adult regardless of sex and had no impact on the male adult lifespan. Finally, we recorded a time lag between metamorphosis from the non-<em>Bt em>and the <em>Bt em>diets, which increased proportionally to Cry concentration in the <em>Bt em>diet.

  5. A Novel Apoptosis Correlated Molecule: Expression and Characterization of Protein Latcripin-1 from <em>Lentinula em>edodes> C91–3

    Directory of Open Access Journals (Sweden)

    Min Huang

    2012-05-01

    Full Text Available An apoptosis correlated molecule—protein Latcripin-1 of <em>Lentinula> edodesem> C91-3—was expressed and characterized in <em>Pichia pastorisem> GS115. The total RNA was obtained from <em>Lentinula edodesem> C91–3. According to the transcriptome, the full-length gene of Latcripin-1 was isolated with 3'-Full Rapid Amplification of cDNA Ends (RACE and 5'-Full RACE methods. The full-length gene was inserted into the secretory expression vector pPIC9K. The protein Latcripin-1 was expressed in <em>Pichia pastorisem> GS115 and analyzed by Sodium Dodecylsulfonate Polyacrylate Gel Electrophoresis (SDS-PAGE and Western blot. The Western blot showed that the protein was expressed successfully. The biological function of protein Latcripin-1 on A549 cells was studied with flow cytometry and the 3-(4,5-Dimethylthiazol-2-yl-2,5-Diphenyl-tetrazolium Bromide (MTT method. The toxic effect of protein Latcripin-1 was detected with the MTT method by co-culturing the characterized protein with chick embryo fibroblasts. The MTT assay results showed that there was a great difference between protein Latcripin-1 groups and the control group (<em>p em>< 0.05. There was no toxic effect of the characterized protein on chick embryo fibroblasts. The flow cytometry showed that there was a significant difference between the protein groups of interest and the control group according to apoptosis function (<em>p em>< 0.05. At the same time, cell ultrastructure observed by transmission electron microscopy supported the results of flow cytometry. The work demonstrates that protein Latcripin-1 can induce apoptosis of human lung cancer cells A549 and brings new insights into and advantages to finding anti-tumor proteins.

  6. Antifungal Activity, Toxicity and Chemical Composition of the Essential Oil of <em>Coriandrum sativumem> L. Fruits

    Directory of Open Access Journals (Sweden)

    Erika H. S. Brito

    2012-07-01

    Full Text Available The aims of this study were to test the antifungal activity, toxicity and chemical composition of essential oil from <em>C. sativumem> L. fruits. The essential oil, obtained by hydro-distillation, was analyzed by gas chromatography/mass spectroscopy. Linalool was the main constituent (58.22%. The oil was considered bioactive, showing an LC50 value of 23 µg/mL in the <em>Artemia salinaem> lethality test. The antifungal activity was evaluated against <em>Microsporum canisem> and <em>Candida> spp. by the agar-well diffusion method and the minimum inhibitory concentration (MIC and the minimum fungicidal concentration (MFC were established by the broth microdilution method. The essential oil induced growth inhibition zones of 28 ± 5.42 and 9.25 ± 0.5 for <em>M. canisem> and <em>Candida> spp. respectively. The MICs and MFCs for <em>M. canisem> strains ranged from 78 to 620 and 150 to 1,250 µg/mL, and the MICs and MFCs for <em>Candida> spp strains ranged from 310 to 620 and 620 to 1,250 µg/mL, respectively. <em>C. sativumem> essential oil is active<em> in vitroem> against <em>M. canis em>and> Candidaem> spp. demonstrating good antifungal activity.

  7. Luminescent CuInS2 quantum dots by partial cation exchange in Cu2- xS nanocrystals

    NARCIS (Netherlands)

    Van Der Stam, Ward; Berends, Anne C.; Rabouw, Freddy T.; Willhammar, Tom; Ke, Xiaoxing; Meeldijk, Johannes D.; Bals, Sara; De Mello Donega, Celso

    2015-01-01

    Here, we show successful partial cation exchange reactions in Cu2-xS nanocrystals (NCs) yielding luminescent CuInS2 (CIS) NCs. Our approach of mild reaction conditions ensures slow Cu extraction rates, which results in a balance with the slow In incorporation rate. With this method, we obtain CIS NC

  8. Enhancement in visible light photocatalytic activity by embedding Cu nanoparticles over CuS/MCM-41 nanocomposite

    Science.gov (United States)

    Sohrabnezhad, Sh.; Karamzadeh, M.

    2017-07-01

    This article indicate the biogenic synthesis of copper nanoparticles (Cu NPs) using the borage flowers extract of Borago officinalis over CuS/MCM-41 nanocomposite (NC). No external reducing was utilized in the developed method. The CuS-MCM-41 NC was used as stabilizing agent. The synthesis of CuS nanostructure in MCM-41 material has been realized by hydrothermal method. Their physiochemical properties have been characterized by X-ray diffraction, transmission electron microscopy (TEM), UV-Visible diffuse reflectance spectroscopy, and Fourier transform infrared spectroscopy. On the basis of TEM images, a layer of Cu NPs has been located over CuS/MCM-41 NC with average diameter of 60-80 nm. The results revealed the spherical nature of the prepared Cu NPs with diameter less than 10 nm. The DR spectra of Cu NPs in MCM-41 and CuS-MCM-41 NCs showed surface plasmon resonance bands at 570 and 500-600 nm, respectively. The photocatalytic activity was evaluated under visible light irradiation using the photocatalytic degradation of methylene blue (MB) as a model reaction. The prepared Cu/CuS/MCM-41 nanocomposite microspheres showed higher photodegradation ability for MB than CuS/MCM-41. The degradation of MB achieved up to 80% after 60 min and the nanocomposite could be recycled and reused.

  9. In-situ STM study of phosphate adsorption on Cu(111), Au(111) and Cu/Au(111) electrodes

    DEFF Research Database (Denmark)

    Schlaup, Christian; Horch, Sebastian

    2013-01-01

    The interaction of Cu(111), Au(111) and Cu-covered Au(111) electrodes with a neutral phosphate buffer solution has been studied by means of cyclic voltammetry (CV) and in situ electrochemical scanning tunneling microscopy (EC-STM). Under low potential conditions, both the Cu(111) and the Au(111...

  10. Rodent hosts of <em>Maritrema> sp. (Digenea, Microphallidae in Sardinia Island

    Directory of Open Access Journals (Sweden)

    Juan Carlos Casanova

    2003-10-01

    Full Text Available Prospections on helminth fauna of rodents were carried out in the Cedrino river (Eastern of Sardinia island. Twelve <em>Rattus rattusem> (L., 1758 and eight <em>Mus domesticusem> (Schwarz & Schwarz, 1943 were captured by Sherman traps. Parasitological study revealed in <em>R. rattusem> the presence of an intestinal helminth belonging to the genus <em>Maritrema> (family Microphallidae. The transmission of this Digenetic Trematode among vertebrates involves the participation of aquatic invertebrate organisms, molluscs and crustacea, acting as intermediate hosts. Dissection of 117 individuals of the Amphipod Crustacea <em>Gammarus italicusem>, collected in the same biotope, allowed the detection of encysted metacercariae. These larvae constitute the infesting stage of the parasite for vertebrates, acting these as definitive hosts ingesting parasitized crustacea as preys. Adults of <em>Maritrema> sp. were also obtained experimentally in the laboratory mice (<em>Mus domesticusem> CD1 strain. These were infested by inoculating them, using gastric probe, metacercarial cysts isolated from <em>G. italicusem>. Post-infection mice dissection was performed at different intervals of time getting adults in various maturity stages. Experimental facts confirm that <em>Maritrema> sp., as it occurs in other trematodes, do not present strict specificity to the definitive host, being able to develop as well in <em>Mus>. In nature, the presence or absence of this digenean in mammals species will be dependent of host ethological factors, mainly related to feeding habitats. This study was partially supported by the ?Comissionat per Recerca i Universitats de la Generalitat de Catalunya? 2001SGR00088.

  11. Análise da transformada em ondeletas aplicada em sinal geofísico

    OpenAIRE

    Bolzan,Maurício José Alves

    2004-01-01

    É mostrada uma análise em ondeletas aplicada em um sinal geofísico, número de manchas solares. Para isso, é dado uma introdução teórica sobre a Transformada em Ondeletas e sobre séries e Transformada de Fourier. A Transformada em Ondeletas é uma ferramenta matemática de grande utilidade aplicação em sinais não-estacionários.

  12. Electromagnetic wave absorption properties of Fe{sub 73}Si{sub 16}B{sub 7}Nb{sub 3}Cu{sub 1}-based composites mixed with fine charcoal powder

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sun-I; Kim, Mi Rae; Sohn, Keun Yong; Park, Won-Wook, E-mail: wwpark@inje.ac.k [Department of Nano-Systems Engineering, Inje University, 607 Obang-dong, Gimhae, Gyeongnam 621-749 (Korea, Republic of)

    2010-05-01

    Fe{sub 73}Si{sub 16}B{sub 7}Nb{sub 3}Cu{sub 1} soft magnetic powder was crystallized to obtain a nano grain structure and mixed with a fine charcoal powder. The mixtures were tape-cast with polymer-based organic binders to form a sheet-type electromagnetic (EM) wave absorption composite. The EM wave absorption properties of the sheets were investigated using a network analyzer. The results showed that addition of charcoal powder improved the EM-absorbing properties of the composite. The power loss of the EM wave was directly related to the imaginary part of the permeability and permittivity, and it was reviewed in detail. Excellent absorption properties were achieved by adding 5 wt % charcoal powder (-500 mesh) to the Fe-based sheets.

  13. Diagnose nutricional de variedades de cana-de-açúcar em argissolos

    Directory of Open Access Journals (Sweden)

    Gilson Moura Filho

    2014-11-01

    Full Text Available A diagnose foliar é um dos métodos mais utilizados para se avaliar a demanda de nutrientes na cultura da cana-de-açúcar, contribuindo para um manejo melhor de fertilizantes. Objetivou-se avaliar o estado nutricional de variedades de cana-de-açúcar através da análise foliar e a mensuração dos teores foliares de macro e micronutrientes. Foram avaliadas as seguintes variedades: RB92579, RB867515, SP81-3250, VAT90-212, VAT90-61, SP83-2847, RB863129, RB931011, RB931566 e RB855113, em dois tipos de solo: Argisssolo Amarelo Distrocoeso Fragipânico (PAdx1 e Argisssolo Amarelo Distrocoeso Abrúptico Fragipânico (PAdx2 na Usina Cansanção de Sinimbú, Jequia da Praia-AL. O delineamento foi o de blocos casualizados arranjado em um fatorial de 2 x 10 consistindo de 10 variedades e quatro repetições para cada solo em estudo, quando foram avaliados os seguintes nutrientes: N, P, K, Ca, Mg, S, Zn, Fe, Mn, Cu e B. O PAdx2 foi o solo que disponibilizou, às plantas, maior quantidade de nutrientes em relação aos nutrientes P, Ca, Mg, Zn e Fe. A variedade SP81-3250 apresentou o melhor desempenho quanto ao teor foliar de nutrientes (K, S, Fe, Mn e Cu seguida pela RB931011, VAT90-61 e RB867515.

  14. Diagnose nutricional da cana-de-açúcar em campos dos Goytacazes (RJ

    Directory of Open Access Journals (Sweden)

    R. A. Reis Jr.

    2002-06-01

    Full Text Available Este trabalho objetivou avaliar o estado nutricional de lavouras canavieiras em Campos dos Goytacazes (RJ por meio de teores adequados e do Sistema Integrado de Diagnose e Recomendação (DRIS, bem como comparar a diagnose nutricional de padrões descritos na literatura com a diagnose obtida de padrões calibrados regionalmente. Foram coletadas 126 amostras foliares de cana-de-açúcar aos quatro meses de idade das plantas. Essas amostras foram analisadas quimicamente para N, P, K, Ca, Mg, S, Cu, Mn e Zn, cujos teores foram comparados com: (a os teores considerados adequados pela literatura, (b os teores médios de canaviais de alta produtividade localizados em Campos dos Goytacazes e (c os teores adequados obtidos do DRIS, determinando-se a freqüência com que o teor de cada nutriente foi inferior aos padrões mencionados. As amostras coletadas foram submetidas à diagnose por meio do DRIS, determinando-se a freqüência com que o índice DRIS de cada nutriente apresentou valor negativo e a freqüência com que o índice DRIS de cada nutriente foi o mais negativo dentro de cada amostra. Padrões de diagnose nutricional desenvolvidos em locais distintos forneceram diagnósticos nutricionais diferentes na cana-de-açúcar. As diagnoses nutricionais obtidas de padrões calibrados regionalmente (teores adequados e DRIS indicaram K, P e S como os principais nutrientes limitantes, enquanto as diagnoses nutricionais de padrões descritos na literatura indicaram N, Zn e Cu como os principais nutrientes limitantes. A calibração regional dos padrões de diagnose da cana-de-açúcar é de grande importância para garantir o sucesso da avaliação do estado nutricional da cana-de-açúcar em Campos dos Goytacazes (RJ.

  15. Copper availability as related to soil copper fractions in oxisols under liming Calagem e os teores disponíveis e as frações de cobre em latossolos

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    Clístenes Williams Araújo do Nascimento

    2003-02-01

    Full Text Available The knowledge of the chemical forms of copper in soils and the relationships of these forms with soil copper availability are important for predicting the copper behavior in the soil-plant system. The present work studies the influence of liming on the available contents of copper as well as on the forms of copper fractions in six types of Oxisols. Soil samples, with and without liming, received copper at rates of 0.0, 20.0 and 40.0 mg dm-3 and remained incubated for 30 days. Then, available copper was extracted with Mehlich-1, Mehlich-3, DTPA and EDTA solutions, and analyzed by atomic absorption spectrophotometry. Additionally, soil samples were extracted in a sequential procedure to determine Cu in fractions of soil, as follows: exchangeable-Cu fraction, organic matter-Cu fraction, Mn oxide-Cu fraction, amorphous Fe oxide-Cu fraction, crystalline Fe oxide-Cu fraction, residual-Cu fraction, and the total Cu content in the soil. Soil samples to which Cu was added presented higher Cu retention in the organic matter fraction with a small percentage retained in the exchangeable-Cu fraction. Liming resulted in a decrease of Cu in the exchangeable and organic matter fractions and an increase in the Fe and Mn oxide fractions and in the residual fraction. Without liming, the organic matter fraction presented the highest contribution to Cu content found in the soil extracts obtained with all extractors, except EDTA. For treatments with liming, Cu contents in the organic matter fraction were better correlated to Cu contents in extracts obtained with DTPA and Mehlich-3.O conhecimento das formas químicas em que se encontra o cobre em solos, e suas relações com os teores disponíveis, são importantes para a previsão do seu comportamento no sistema solo-planta. Nesse sentido, este trabalho estuda a influência da calagem sobre os teores disponíveis e sobre o fracionamento de Cu em amostras de seis Latossolos. Essas amostras, submetidas ou não a

  16. Metais pesados em solos de área de rejeitos de indústria de processamento de zinco

    Directory of Open Access Journals (Sweden)

    M. R. Ribeiro-Filho

    1999-06-01

    Full Text Available Apesar de a poluição do solo ser amplamente constatada, estudos sobre as concentrações e formas dos metais pesados em solos e seus efeitos no ecossistema são ainda pouco enfatizados, principalmente em condições tropicais. O presente estudo foi desenvolvido em área de rejeitos de uma unidade de extração e industrialização de zinco pertencente à Companhia Mineira de Metais-CMM, em Três Marias (MG, com o objetivo de avaliar as quantidades e formas de metais pesados em sete locais representativos da área. Os locais foram selecionados para amostragem, baseando-se em diferenças na forma de contaminação, aspectos de solo, topografia e vegetação. Realizaram-se análises químicas de fracionamento de metais pesados e extrações simples com DTPA e Mehlich-1, buscando determinar os teores e formas dos metais na superfície e em profundidade e fazer inferências sobre o potencial de risco ambiental desses metais. Os teores totais dos metais nas camadas superficiais dos locais estudados foram, em média, de: 13.533 mg kg-1, para Zn; 170 mg kg-1, para Cd; 865 mg kg-1, para Cu, e 612 mg kg-1, para Pb, enquanto os teores trocáveis (MgCl2 nessas mesmas camadas variaram de 231 a 1.407 mg kg-1, para Zn; 14 a 390 mg kg-1, para Cd, e 11 a 33 mg kg-1, para Pb; o Cu raramente ocorreu nesta forma. Os solos dos locais estudados, com teores excessivos de Zn, Cd, Cu e Pb, são considerados poluídos. Em determinados locais contaminados por escoamento (superficial e subsuperficial e arraste de material de solo e rejeito, a poluição mostrou-se mais evidente nas camadas superficiais. No local da ustulação, verificou-se maior percentagem de Zn trocável em todos os níveis de profundidade. Nos demais locais, o Cd apresentou também grandes concentrações nas formas trocáveis, razão por que tal elemento oferece maior risco de contaminação ambiental. De modo geral, a ocorrência de Zn foi maior nas formas carbonato e residual, enquanto o Cd

  17. Evolution of microstructure in centrifugal cast Al-Cu alloy

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    Sui Yanwei

    2010-02-01

    Full Text Available In this research, the effects of centrifugal radius and mould rotation speed on microstructure in centrifugal-cast Al-Cu alloy have been investigated. The results show that, with increase of the centrifugal radius or mould rotation speed, the grain size of centrifugal-cast Al-Cu alloy decreases gradually, while the content of white phases containing the Al2Cu precipitated from α-phase, divorced eutectic and regular eutectic microstructure increases, leading to higher Cu macrosegregation. The variation level of microstructure in centrifugal-cast Al-Cu alloy at 600 rpm of mould rotation speed is greater than that at 300 rpm.

  18. Rare-earth magnetism in cuprates with T' structure. [GdPrCuO; GdNdCuO; GdSmCuO; GdEuCuO

    Energy Technology Data Exchange (ETDEWEB)

    Czjzek, G. (Kernforschungszentrum Karlsruhe, INFP and ITP (Germany)); Roth, G. (Kernforschungszentrum Karlsruhe, INFP and ITP (Germany)); Kroener, T. (Kernforschungszentrum Karlsruhe, INFP and ITP (Germany)); Adelmann, P. (Kernforschungszentrum Karlsruhe, INFP and ITP (Germany))

    1994-02-01

    Cuprates of composition (Gd[sub 1-x]R[sub x])[sub 2]CuO[sub 4], R = Pr, Nd, Sm, Eu, have been studied by complementary experimental techniques. Only in compounds with Sm, exchange interactions between Sm and Cu moments are ineffective since the easy axis of the Sm moments is perpendicular to the Cu - O planes to which the Cu moments are confined. Here, we present new evidence that in the other cuprates with magnetic rare earths, R - Cu exchange interactions strongly influence the magnetic properties. (orig.)

  19. Electroless deposition of Cu on multiwalled carbon nanotubes

    Institute of Scientific and Technical Information of China (English)

    YUAN Dingsheng; LIU Yingliang

    2006-01-01

    Copper has been deposited on the surface of multiwalled carbon nanotubes (MWNTs) and inside MWNTs by electroless deposition. The as-prepared Cu-MWNT composite materials have been characterized by X-ray diffractometer(XRD), transmission electron microscopy (TEM), and electrochemical measurement. XRD analyses showed that Cu was a face-centered cubic (fcc) structure. The average size of Cu was calculated by Scherrer's formula from XRD data, and it was11 nm. TEM revealed that Cu grains on the surface of MWNTs were uniform with the sizes of about 30-60 nm. The electrochemical measurement indicated that Cu-MWNT composite materials possessed fine electron conductivity.

  20. Effects of Cu2+ on characteristic of SV currents

    Institute of Scientific and Technical Information of China (English)

    ZHANG; Liping; YANG; Pin

    2006-01-01

    Applying the patch-clamp technique to vacuoles from Radish we studied the effects of Cu2+ on Slow Vacuolar (SV) current's characteristic. Our results show that Cu2+ in bath solution at higher concentration inhibits SV currents and the percentage of inhibition increases with increasing concentration and changes with different voltage. When at lower concentration, Cu2+ significantly promotes the SV currents and the promotion ratio decrease with increasing voltage. At the same time, the time constants of activation become lesser after adding Cu2+. These results show that there may be some Cu2+ binding sites on SV channels and binding to which can change SV current's characteristic.

  1. Studying Cu Alloy Corrosion Products in Cooling Liquid

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The effect of cooiing liquid used for heat exchangers on the Cu alloy corrosion products has been examined using potential-time measurements under applied current condition (anodizing), potentiodynamic polarization, X-ray diffraction (XRD) and infrared spectroscopy (IR). The corrosion products formed on the Cu alloy surface during anodizing, are Cu2O, Cu2(OH)3CI, and Cu2S. NaCI is detected in the corrosion products. The film formation depends on the applied current and the shift of potential to nobler direction indicates its formation progress.

  2. Bi-Se doped with Cu, p-type semiconductor

    Science.gov (United States)

    Bhattacharya, Raghu Nath; Phok, Sovannary; Parilla, Philip Anthony

    2013-08-20

    A Bi--Se doped with Cu, p-type semiconductor, preferably used as an absorber material in a photovoltaic device. Preferably the semiconductor has at least 20 molar percent Cu. In a preferred embodiment, the semiconductor comprises at least 28 molar percent of Cu. In one embodiment, the semiconductor comprises a molar percentage of Cu and Bi whereby the molar percentage of Cu divided by the molar percentage of Bi is greater than 1.2. In a preferred embodiment, the semiconductor is manufactured as a thin film having a thickness less than 600 nm.

  3. Contribution to the knowledge of <em>Apodemus> genus in the Gran Paradiso National Park

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    Paolo Debernardi

    2003-10-01

    Full Text Available Abstract Between 1992 and 2001, small mammals were trapped in the Gran Paradiso National Park (NW Italy, using Capture-Mark-Recapture techniques. According to a sample of data collected in August, the following percentages were found for the genus <em>Apodemus>: 25.9% of the individuals caught in alder shrubwoods, 20.9% in hardwoods, 12.1% in open habitat-types and 3.1% in coniferous woods. Further trapping, carried out in winter in the villages inside the Park, demonstrated that <em>Apodemus> occurrence inside the buildings was quite common. Fiftytwo specimens were sacrificed and identified by protein electrophoresis and/or molecular analyses as <em>A. alpicolaem> (N= 14, <em>A. flavicollisem> (N= 21 and <em>A. sylvaticusem> (N= 17. External morphology and biometric parameters were analysed on the above specimens, as were cranial features, and the effectiveness of the determination technique proposed by Reutter <em>et al.em> on the study area material was verified. This technique enabled us to determine other specimens (mainly from discarded bottles using skull analysis. <em>A. flavicollisem> (recorded from the lowest altitude of the area, 750 m, up to 2123 m a.s.l. dominated in hardwoods. <em>A. alpicolaem> (recorded from 1580 m to 2423 m is more abundant above 1750 m, in alder shrubwoods and in open habitat-types, characterized by patches of rocky elements, low ligneous and herbaceus vegetation. All the individuals caught inside buildings were <em>A. sylvaticusem>, but this species (recorded from 750 m to 1960 m was scarcely observed in natural habitats. <em>Strix alucoem> and <em>Aegolius funereusem> prey remains, collected in the area during the breeding period of both owls, were examined. <em>Apodemus> accounted for 13.7% of prey and 9.4% of biomass eaten by <em>Strix alucoem> and for 7.2% of prey and 7.3% of biomass consumed by <em>Aegolius funereusem>. Riassunto

  4. Allometric and Isometric variations in the Italian <em>Apodemus sylvaticusem> and <em>Apodemus flavicollisem> with respect to the conditions of allopatry and sympatry / Variazioni allometriche e isometriche in <em>Apodemus sylvaticusem> e <em>Apodemus flavicollisem> italiani, rispetto alle condizioni di allopatria e simpatria

    Directory of Open Access Journals (Sweden)

    Giovanni Amori

    1986-12-01

    Full Text Available Abstract In Italy there are two species of <em>Apodemus> (<em>Sylvaemus>: <em>Apodemus sylvaticusem> on the mainland and the main island, and <em>Apodemus flavicollisem> only on the mainland. The trend of some morphometric characters of the skull (incisive foramen length - FI; interorbital breadth = IO; length of palatal bridge = PP; upper alveolar length = $M^1M^3$ was analized and some theoretical models verified for <em>A. sylvaticusem>. If one considers the sympatric population of <em>A. sylvaticusem> and <em>A. flavicollisem> simultaneously the characters PP, IO and $M^1M^3$ appear significantly isometric being directly correlated ($P leq O.O1$, while FI character results allometric with respect to the previous ones, as expected. If one considers the sympatric populations of each of the species separately, the scenario is different. For <em>A. sylvaticusem> only PP and $M^1M^3$ are isometric ($P leq 0.05$. For <em>A. flavicollisem> only $M^1M^3$ and FI appear to be correlated, although not as significantly as for <em>A. sylvaticusem> ($P le 0.05$; one tail. The insular populations of <em>A. sylvaticusem> do not show significant correlations, except for FI and $M^1M^3$ ($P le 0.05$. On the contrary, considering all populations, sympatric and allopatric, of <em>A. sylvaticusem> at the same time are significant correlations ($P le 0.05$ in all combinations of characters, except for those involving the IO. We suggest that the isometric relations in sympatric assemblages are confined within a morphological range available to the genus <em>Apodemus>. In such a space, the two species are split in two different and innerly homogeneous distributions. We found no evidence to confirm the niche variation hypothesis. On the contrary, the variability expressed as SO or CV's appears higher in the sympatric populations than in the allopatric ones, for three of the four characters, confirming previous results

  5. Fitodisponibilidade e teores de metais pesados em um latossolo amarelo distrófico e em plantas de cana-de-açúcar adubadas com composto de lixo urbano

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    F. C. Oliveira

    2002-09-01

    Full Text Available A presença de metais pesados em compostos de lixo urbano é um dos principais motivos da insegurança de sua utilização agronômica. Desta forma, foram avaliados os efeitos da aplicação sucessiva do composto de lixo sobre os teores de Cd, Cr, Cu, Ni, Pb e Zn em um Latossolo Amarelo distrófico, em plantas de cana-de-açúcar, e a fitodisponibilidade desses metais medida pelos extratores DTPA, HCl 0,1 mol L-1 e Mehlich-3. Experimento de campo foi realizado nos anos agrícolas 1996/97 e 1997/98, sendo o composto aplicado nas doses de 0, 20, 40 e 60 Mg ha-1 e de 0, 24, 48 e 72 Mg ha-1, respectivamente. A aplicação consecutiva do composto aumentou os teores totais de Cu do solo que variaram, em relação à testemunha, de 12 a 25 %, no primeiro ano agrícola, e de 27 a 88 %, no segundo ano agrícola. Para Zn, esses valores variaram de 12 a 72 % e de 72 a 156 %, no primeiro e no segundo ano, respectivamente, e de Cr de 12 a 25 %, no segundo ano. Os teores totais de Cd, Ni e Pb, no solo, e de Cd, Cr, Ni e Pb, nas folhas, colmos e caldo das plantas, mantiveram-se abaixo do limite de determinação. Os teores de Cu e Zn nas amostras de plantas não aumentaram. Os extratores químicos praticamente não diferiram entre si e apresentaram capacidades restritas para a avaliação da fitodisponibilidade dos metais pesados decorrente das baixas concentrações nas amostras de solo e planta.

  6. STRUCTURAL AND ELECTRONIC PROPERTIES OF CuO, CuO2 AND Cu2O NANOCLUSTERS – A DFT APPROACH

    Directory of Open Access Journals (Sweden)

    Chandiramouli RAMANATHAN

    2015-06-01

    Full Text Available The realistic structures of CuO, CuO2 and Cu2O were completely optimized using density functional theory approach. The different structures were optimized to study the structural stability, dipole moment, point symmetry, HOMO-LUMO gap, ionization potential, electron affinity and binding energy of CuO, CuO2 and Cu2O. The electronic properties of clusters were discussed in terms of HOMO-LUMO gap, density of states, ionization potential and electron affinity. This information will provide an insight for the synthesis of nanomaterials with proper geometry which finds its potential importance in engineering applications.DOI: http://dx.doi.org/10.5755/j01.ms.21.2.6459

  7. Extratores para avaliação da disponibilidade de metais pesados em solos adubados com vermicomposto de lixo urbano

    Directory of Open Access Journals (Sweden)

    Mantovani José Ricardo

    2004-01-01

    Full Text Available Os objetivos deste trabalho foram selecionar extratores químicos para avaliação da disponibilidade de metais pesados em solos tratados com vermicomposto de lixo urbano e calcário, e verificar os efeitos destes insumos nos teores disponíveis de metais pesados em solos. Foram realizados dois ensaios em casa de vegetação. Em um deles, foi usado um Latossolo Vermelho distroférrico e, no outro, um Argissolo Vermelho-Amarelo eutrófico, e, em ambos, a alface foi utilizada como planta-teste. O delineamento experimental de cada experimento foi em blocos ao acaso, em esquema fatorial 5x5, com quatro repetições, combinando-se doses de corretivos da acidez para elevar a saturação por bases a 40%, 50%, 60%, 70% e 80%, e o equivalente a 0, 25, 50, 75 e 100 t ha-1 de vermicomposto. Os extratores DTPA e Mehlich 3 detectam aumento nos teores de Ni, Pb, Cu e Zn em solos argiloso e arenoso adubados com vermicomposto de lixo urbano. O DTPA é mais eficiente que os extratores Mehlich 1 e Mehlich 3 na avaliação das alterações nos teores disponíveis dos metais pesados provocadas pelas mudanças no pH no solo argiloso. O Mn é o único elemento cuja disponibilidade é avaliada eficientemente tanto no solo argiloso como no arenoso, pelo DTPA.

  8. In situ quantitative study of microstructural evolution at the interface of Sn3.0Ag0.5Cu/Cu solder joint during solid state aging

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hailong [State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin 150001 (China); An, Rong, E-mail: anr@hit.edu.cn [Key Laboratory of Micro-systems and Micro-structures Manufacturing, Harbin Institute of Technology, Ministry of Education, Harbin 150080 (China); Wang, Chunqing; Jiang, Zhi [State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin 150001 (China)

    2015-06-15

    Highlights: • Cu dissolution during reflowing was mainly occurred under the gaps between scallops. • Though IMC growth was diffusion-controlled, consumption of Cu substrate was not. • Growth of Cu{sub 3}Sn layer in Sn3.0Ag0.5Cu/Cu solder joint was on the both sides. • Ag and Cu lead to a thinner Cu{sub 3}Sn layer due to inhibit the diffusion of Sn into Cu. - Abstract: In situ microstructural evolution at the interface of Sn3.0Ag0.5Cu/Cu solder joint during solid state aging was quantitatively studied by nanoindentation. The morphology of Cu{sub 6}Sn{sub 5} gradually altered from scallop type to layer type. Though the growth of IMCs was diffusion-controlled, the consumption of Cu substrate was not linear with the square root of aging time. At the initial stage of solid state aging, the Cu atoms essential to the growth of IMCs were mainly from the supersaturated solder matrix. When the Cu atoms from supersaturated solder matrix were exhausted, the Cu atoms for the growth of IMCs were primarily from the Cu substrate. In addition, the IMCs formed at this state were principally used to fill up the gaps between scallops. After the gaps disappeared, the consumption of Cu substrate slowed down. Furthermore, the growth of Cu{sub 3}Sn layer in Sn3.0Ag0.5Cu/Cu solder joint was on the both sides with layer type. Since the Sn atoms were inhibited to diffuse into the Cu substrate by the alloying elements of Ag and Cu, the thickness of Cu{sub 3}Sn layer in SnAgCu/Cu solder joint was much thinner than that in pure Sn/Cu solder joint.

  9. Planejamento em Saúde

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    Antonio José Costa CARDOSO

    2014-03-01

    Full Text Available Esse texto pretendeu subsidiar aula sobre Planejamento e Avaliação em Saúde para os Analistas Técnicos de Políticas Sociais lotados no Ministério da Saúde (MS, na perspectiva de promover uma maior compreensão dos antecedentes históricos do planejamento em saúde no Brasil e na América Latina, do referencial teórico metodológico do planejamento estratégico e participativo, e refletir sobre os avanços e desafios que se apresentam no atual contexto de construção do Sistema Único de Saúde (SUS. Neste sentido, foi estruturado na perspectiva de responder a três questões orientadoras: 1 Como tem se dado esse processo de coordenação do Planejamento Estratégico Nacional no âmbito do SUS, em cooperação técnica com os Estados, Municípios e Distrito Federal? 2 Quais são as tecnologias de gestão e planejamento em saúde adotadas pelo MS para conduzir esses processos de forma integrada? 3 Como se dá o gerenciamento das ações no MS? Como os planos, projetos e programas são monitorados pelas equipes responsáveis?

  10. Action of Chitosan Against <em>Xanthomonas> Pathogenic Bacteria Isolated from <em>Euphorbia pulcherrimaem>

    Directory of Open Access Journals (Sweden)

    Yanli Wang

    2012-06-01

    Full Text Available The antibacterial activity and mechanism of two kinds of chitosan were investigated against twelve <em>Xanthomonas> strains recovered from <em>Euphorbia pulcherrimaem>. Results indicated that both chitosans markedly inhibited bacterial growth based on OD loss. Furthermore, the release of DNA and RNA from three selected strains was increased by both chitosans. However, the release of intracellular proteins was inhibited by both chitosans at different concentration and incubation times, except chitosan A at 0.1 mg/mL for 0.5 h incubation and 0.2 mg/mL for 2.0 h incubation increased the release of proteins, indicating the complexity of the interaction and cell membranes, which was affected by incubation time, bacterial species, chitosan type and concentration. Transmission electron microscopic observations revealed that chitosan caused changes in protoplast concentration and surface morphology. In some cells, the membranes and walls were badly distorted and disrupted, while other cells were enveloped by a thick and compact ribbon-like layer. The contrary influence on cell morphology may explain the differential effect in the release of material. In addition, scanning electron microscope and biofilm formation test revealed that both chitosans removed biofilm biomass. Overall, this study showed that membrane and biofilm play an important role in the antibacterial mechanism of chitosan.

  11. EMS wave logger data processing

    NARCIS (Netherlands)

    Verhagen, H.J.

    2013-01-01

    Waves can be measured in several ways. One way of measuring waves is by measuring the wave pressure at a certain depth using a pressure sensor and calculate the wave information from the pressure record. The EMS wave logger uses a Honeywell MLH 050 PGP 06A pressure sensor. The information is stored

  12. Synthesis and Characterization of Some New <em>C2em> Symmetric Chiral Bisamide Ligands Derived from Chiral Feist’s Acid

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    Assem Barakat

    2012-05-01

    Full Text Available The hemilabile chiral <em>C2em> symmetrical bidentate substituted amide ligands (1<em>R>,2<em>R>-5a-d and (1<em>S>,2<em>S>-6a-d were synthesized in quantitative yield from (1<em>R>,2<em>R>-(+-3-methylenecyclo-propane-1,2-dicarboxylic acid (1<em>R>,2<em>R>-3 and (1<em>S>,2<em>S>-(--3-methylene-cyclopropane-1,2-dicarboxylic acid (1<em>S>,2<em>S>-3, in two steps, respectively. The chiral Feist’s acids (1<em>R>,2<em>R>-3 and (1<em>S>,2<em>S>-3 were obtained in good isomeric purity by resolution of <em>trans>-(±-3-methylene-cyclopropane-1,2-dicarboxylic acid from an 8:2 mixture of <em>tert>-butanol and water, using (<em>R-(+-α>-methylbenzyl amine as a chiral reagent. This process is reproducible on a large scale. All these new synthesized chiral ligands were characterized by 1H-NMR, 13C-NMR, IR, and mass spectrometry, as well as elemental analysis and their specific rotations were measured. These new classes of <em>C2em> symmetric chiral bisamide ligands could be of special interest in asymmetric transformations.

  13. Phase equilibria of the Cu-Sn-Ti ternary system at 823K

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    Guo-jun Zhou

    2017-02-01

    Full Text Available The isothermal section in the Cu-Sn enrich part of the Cu-Sn-Ti ternary system at 823K was determined by using solid-solid-liquid diffusion triple approach. One ternary compound CuSnTi was found, and 12 three-phase fields were detected. The following 10 three-phase regions are well established: CuTi2+CuTi+Sn5Ti6, Sn5Ti6+Sn3Ti2+ CuSnTi, Liquid+Sn3Ti2+CuSnTi, Liquid+CuSnTi+Cu3Sn, CuTi+Cu4Ti3+Sn5Ti6, CuSnTi+Cu4Ti3+Sn5Ti6, CuSnTi+Cu3Sn+Cu41Sn11, CuSnTi+Cu41Sn11+Bcc_a2, CuSnTi+Cu4Ti+Cu, and CuSnTi+Bcc_a2+Cu. Phase relations in the Ti-enrich corner of this system require further investigation.

  14. A Controllable Synthetic Route for Preparing Graphene-Cu and Graphene-Cu2O Nanocomposites Using Graphene Oxide-CuO as a Precursor

    Institute of Scientific and Technical Information of China (English)

    CHEN Li; ZHU Junwu; BI Huiping; MENG Xiaoqian; YAO Pengcheng; HAN Qiaofeng

    2015-01-01

    The development of convenient method to obtain graphene-based nanocomposites is a key issue for their application. Herein, we described a facile route for synthesizing graphene-Cu and graphene-Cu2O nanocomposites using graphene oxide-CuO as a precursor. Remarkably, the different nanocomposites could be formed just by varying the reaction temperature and time. This work provides a feasible route for the preparation of graphene-based nanocomposites with various constituents.

  15. Bactericidal behavior of Cu-containing stainless steel surfaces

    Science.gov (United States)

    Zhang, Xiangyu; Huang, Xiaobo; Ma, Yong; Lin, Naiming; Fan, Ailan; Tang, Bin

    2012-10-01

    Stainless steels are one of the most common materials used in health care environments. However, the lack of antibacterial advantage has limited their use in practical application. In this paper, antibacterial stainless steel surfaces with different Cu contents have been prepared by plasma surface alloying technology (PSAT). The steel surface with Cu content 90 wt.% (Cu-SS) exhibits strong bactericidal activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) within 3 h. Although the Cu-containing surface with Cu content 2.5 wt.% (CuNi-SS) can also kill all tested bacteria, this process needs 12 h. SEM observation of the bacterial morphology and an agarose gel electrophoresis were performed to study the antibacterial mechanism of Cu-containing stainless steel surfaces against E. coli. The results indicated that Cu ions are released when the Cu-containing surfaces are in contact with bacterial and disrupt the cell membranes, killing the bacteria. The toxicity of Cu-alloyed surfaces does not cause damage to the bacterial DNA. These results provide a scientific explanation for the antimicrobial applications of Cu-containing stainless steel. The surfaces with different antibacterial abilities could be used as hygienic surfaces in healthcare-associated settings according to the diverse requirement of bactericidal activities.

  16. ZrN/Cu nanocomposite film - a novel superhard material

    Energy Technology Data Exchange (ETDEWEB)

    Musil, J.; Zeman, P. [Univ. of West Bohemia, Plzen (Czech Republic). Dept. of Phys.; Hruby, H.; Mayrhofer, P.H. [Montanuniversitaet Leoben (Austria). Inst. fuer Metallkunde und Werkstoffpruefung

    1999-11-01

    This article reports on the structure and hardness of ZrCu-N films prepared by dc reactive magnetron sputtering of a ZrCu alloyed target in a mixture of Ar+N{sub 2} using a round planar unbalanced magnetron of diameter 100 mm. It was found that there is a strong correlation between the structure of the film and its hardness. The hard (<40 GPa) ZrCu-N films are characterized by many weak reflections from poly-oriented ZrN and Cu grains. In contrast, the superhard ({>=}40 GPa) ZrCu-N films are characterized by a strong reflection from ZrN grains with a dominate ZrN(111) orientation and no reflections from Cu. The superhard ZrCu-N films with a hardness of 54 GPa are nc-ZrN/Cu nanocomposite films composed of strongly oriented ZrN grains surrounded by a thin layer of Cu. These films exhibit a high elastic recovery of about 80% (determined by a microhardness tester) and contain approximately 1-2 wt.% Cu. The superhard nc-ZrN/Cu nanocomposite films represent a new class of superhard materials of the type nc-MeN/metal. (orig.)

  17. Growth and magnetic properties dependence of the Co–Cu/Cu films electrodeposited under high magnetic fields

    Energy Technology Data Exchange (ETDEWEB)

    Franczak, Agnieszka, E-mail: agnieszka.franczak@mtm.kuleuven.be [Laboratoire d’Ingénierie et Sciences des Matériaux (LISM EA 4695), Université de Reims Champagne-Ardenne, UFR Sciences et Naturelles, Bat. 6, Moulin de la Housse, BP 1039, 51687 Reims Cedex 2 (France); Department of Materials Science (MTM), KU Leuven, Kasteelpark Arenberg 44, 3001 Haverlee (Leuven) (Belgium); Levesque, Alexandra [Laboratoire d’Ingénierie et Sciences des Matériaux (LISM EA 4695), Université de Reims Champagne-Ardenne, UFR Sciences et Naturelles, Bat. 6, Moulin de la Housse, BP 1039, 51687 Reims Cedex 2 (France); Zabinski, Piotr [Laboratory of Physical Chemistry and Electrochemistry, Faculty of Non-Ferrous Metals, AGH University of Science and Technology, al. A. Mickiewicza 30, 30059 Krakow (Poland); Li, Donggang [Key Laboratory of Electromagnetic Processing of Materials (Ministry of Education), Northeastern University, 314 Box, 110004 Shenyang (China); Czapkiewicz, Maciej [Department of Electronics, AGH University of Science and Technology, al. A. Mickiewicza 30, 30059 Krakow (Poland); Kowalik, Remigiusz [Laboratory of Physical Chemistry and Electrochemistry, Faculty of Non-Ferrous Metals, AGH University of Science and Technology, al. A. Mickiewicza 30, 30059 Krakow (Poland); Bohr, Frédéric [Laboratoire d’Ingénierie et Sciences des Matériaux (LISM EA 4695), Université de Reims Champagne-Ardenne, UFR Sciences et Naturelles, Bat. 6, Moulin de la Housse, BP 1039, 51687 Reims Cedex 2 (France); and others

    2015-07-15

    The present work is focused on the investigations of magnetic properties dependence on microstructure of Co–Cu/Cu films electrodeposited under superimposed high magnetic field. The experimental results indicate a strong effect of an external magnetic field on the morphology of deposited films, more precisely on the Co:Cu ratio that determines the film growth. It is shown that the Co–Cu/Cu films electrodeposited without superimposed magnetic field consisted of two clearly visible features: compact film with incorporated granular particles. Under a superimposed external high magnetic field the privilege growth of the particles was induced. As a consequence, development of the well-defined branched structure of Co–Cu/Cu film was observed. In contrary, the phase compositional investigations do not reveal any changes in the phase formation during electrodeposition under magnetic field conditions. Thus, it is assumed that a strong growth of Co–Cu/Cu films in (111) direction under magnetic or non-magnetic electrodeposition conditions is related with the growth of Cu (111) plane and embedded into it some of the Co fcc atoms of same (111) orientation, as well as the Co hcp atoms that grows in the (002) direction. This non-equilibrium growth of Co–Cu/Cu films under magnetic deposition conditions affects strongly the magnetic properties of deposited films, revealing that films obtained under magnetic fields higher than 3 T were no more magnetic materials. - Highlights: • Co–Cu/Cu electrodeposits were obtained at elevated temperature under HMFs. • The effects of HMFs on microstructure and magnetic properties were investigated. • Interesting morphological changes due to HMFs has been observed. • Changes in Co:Cu ratio due to HMFs modified the magnetic properties of deposits.

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

    Directory of Open Access Journals (Sweden)

    Vittorio Guberti

    1991-07-01

    Full Text Available 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 vulpisem> (3.3%, <em>Dipylidium caninumem> (2.6%, <em>Taenia crassicepsem> (2%. All foxes were negative for <em>Trichinella> sp. A statistical analysis was performed to evaluate differences in the parasitic fauna according to the sex and age classes of the hosts. The role that the fox could have as a reservoir of helminthic zoonoses is discussed. The results are compared with those of similar studies carried out in Italy. Riassunto Nel periodo 1984-1987 è stata condotta un'indagine parassitologica su 153 volpi abbattute nell'Appennino romagnolo. Sono stati reperiti i seguenti parassiti: <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 vulpisem> (3,3%, <em>Dipylidium caninumem> (2,6%, <em>Taenia crassicepsem> (2%. Tutte le volpi esaminate sono risultate negative per <em>Trichinella> sp. È stata effettuata l'analisi statistica dei dati per evidenziare eventuali differenze della fauna parassitaria in relazione al sesso e all'età delle volpi. Sulla base dei dati ottenuti viene discussa l'importanza che la Volpe può assumere come serbatoio di zoonosi elmintiche. I risultati acquisiti sono inoltre comparati con quelli ottenuti in analoghe ricerche condotte in Italia.

  19. First sign of <em>Clethrionomys glareolusem> in the Po valley plain / Prima segnalazione in Pianura Padana di <em>Clethrionomys glareolusem>

    Directory of Open Access Journals (Sweden)

    Luis Nieder

    1987-07-01

    Full Text Available Abstract The presence of <em>Clethrionomys glareolusem> (Schreber, 1790 populations is reported in the Po valley, formerly considered outside the distribution area of the species. An initial series of captures was made in the high-water area of the Po near S. Nazzaro (Monticelli d'Ongina - PC following with research was extended along the river's banks in Emilia both upstream and downstream. The search for this species was carried out by analysing food pellets relating to <em>Strix alucoem>, <em>Tyto albaem> e <em>Athene noctuaem>, thought to be among the most common predators of these intensive herbaceous and arboreal agricultural biocoenosis. The information we gathered was integrated with other Authors' unpublished and bibliographical data. The presence of <em>C. glareolusem> was noted in habitats quite different from the expected ones. Many of the problems raised by the presence of this species in "islands" along the main body of the Po river and its tributaries, and by its presumed absence from particulary suitable environments such as the Carrega woods, the Ticino park and Mesola wood must still be resolved. Riassunto Viene segnalata la presenza di popolazioni di <em>Clethrionomys glareolusem> (Schreber 1790 nella pianura Padana precedentemente considerata al di fuori dell'areale della specie. A partire da una prima serie di catture nell'area golenale del Po presso S. Nazzaro (Monticelli d'Ongina - PC, si è successivamente proceduto ad allargare l'area di ricerca lungo l'argine emiliano del Po, sia a monte sia a valle. La ricerca di questa specie è avvenuta tramite l'analisi di boli alimentari relativi a <em>Strix alucoem>, <em>Tyto albaem> e <em>Athene noctuaem>, ritenuti tra i più comuni predatori di queste biocenosi agricole intensive erbacee ed arboree. I dati da noi raccolti sono stati integrati con quelli bibliografici e inediti di altri Autori. È stata riscontrata la presenza

  20. Stability and diffusion of Hg implanted YBa$_{2}$Cu$_{3}$O$_{6+x}$

    CERN Document Server

    Araújo, J P; Wahl, U; Marques, J G; Alves, E; Amaral, V S; Lourenço, A A; Galindo, V; Von Papen, T; Senateur, J P; Weiss, F; Vantomme, A; Langouche, G; Melo, A A; Da Silva, M F A; Soares, J C; Sousa, J B

    1999-01-01

    The radioactive isotope $^{197m}$Hg was implanted at 60 keV with low fluences (10$^{13}$ ions/cm$^{2}$ ) into YBa$_{2}$Cu$_{3}$O$_{6+x}$ (YBCO) superconducting thin films at ISOLDE/CERN. We report on the Hg dynamics and stability inside the YBCO lattice as a function of annealing temperature up to 890 K in vacuum or O$_{2}$ atmosphere. The perturbed angular correlation (PAC) technique was used for probing the Hg behavior at the atomic scale, while by monitoring the sample's activity in situ the Hg outdiffusion was studied. We found that Hg ions occupy unique lattice sites and that Hg should be bound to two apical oxygens. Hg diffusion occurs only for annealing temperatures above 653 K, in vacuum. The Hg migration energy was estimated to be EM = 1.58 $\\pm$ 0.15 eV.

  1. Nanoporous CuS with excellent photocatalytic property

    Science.gov (United States)

    Xu, Wence; Zhu, Shengli; Liang, Yanqin; Li, Zhaoyang; Cui, Zhenduo; Yang, Xianjin; Inoue, Akihisa

    2015-12-01

    We present the rational synthesis of nanoporous CuS for the first time by chemical dealloying method. The morphologies of the CuS catalysts are controlled by the composition of the original amorphous alloys. Nanoporous Cu2S is firstly formed during the chemical dealloying process, and then the Cu2S transforms into CuS. The nanoporous CuS exhibits excellent photocatalytic activity for the degradation of the methylene blue (MB), methyl orange (MO) and rhodamine B (RhB). The excellent photocatalytic activity of the nanoporous CuS is mainly attributed to the large specific surface area, high adsorbing capacity of dyes and low recombination of the photo generated electrons and holes. In the photo degradation process, both chemical and photo generated hydroxyl radicals are generated. The hydroxyl radicals are favor in the oxidation of the dye molecules. The present modified dealloying method may be extended for the preparation of other porous metal sulfide nanostructures.

  2. A comparison between Cu-ZSM-5, Cu-S-1 and Cu-mesoporous-silica-alumina as catalysts for NO decomposition

    Energy Technology Data Exchange (ETDEWEB)

    Moretti, Giuliano [Centro CNR `SACSO`, Dipartimento di Chimica, Universita `La Sapienza`, Piazzale A. Moro 5, 00185 Rome (Italy); Dossi, Carlo; Fusi, Achille; Recchia, Sandro; Psaro, Rinaldo [Centro CNR `CSSSCMTBSO`, Dipartimento di Chimica Inorganica, Metallorganica e Analitica, Universita di Milano, Via Venezian 21, 20133 Milan (Italy)

    1998-01-04

    We prepared H-ZSM-5 (Si/Al=80), amorphous mesoporous silica-alumina (MSA, Si/Al=90), and Silicalite-1 (S-1) according to the methods described by Bellussi and co-workers, and compared their ion-exchange capacity for copper ions. The Cu-ZSM-5, Cu-MSA and Cu-S-1 samples thus obtained have been investigated as catalysts for the NO decomposition reaction at 773K.We found that using copper acetate solutions with concentrations in the range 0.008M{<=}[Cu{sup 2+}]{<=}0.1M, both at room temperature and at 323K, it is very easy to prepare over-exchanged Cu-ZSM-5, Cu-S-1 and Cu-MSA catalysts. XRD and Vis-UV DRS techniques show that after thermal treatments of the fresh samples in air at 823K for 4h no segregation of CuO phase occurs, suggesting the presence of low nuclearity [Cu{sub n}O{sub x}(OH){sub y}]{sup q+} species (q=2(n-x)-y{>=}0). These results were confirmed by TPR studies. At 773K only over-exchanged Cu-ZSM-5 catalysts showed NO decomposition activity (NO 1% in He, W/F=0.1gs/cm{sup 3}) with a turnover frequency essentially determined by the Si/Al ratio, in agreement with previous literature data. Instead, the activity of Cu-S-1 and Cu-MSA catalysts was not measurable under our experimental conditions.The present results confirm that the framework topology and the presence of framework AlO{sup -}{sub 4} species are fundamental to develop active copper species for NO decomposition. It is demonstrated that the active sites in Cu-ZSM-5 consist of copper species strongly anchored to framework AlO{sup -}{sub 4} species. The most active sites, as they occur only on ZSM-5 support with the lower Si/Al atomic ratios, might consist of dimeric Cu species (Cu{sup +}...Cu{sup 2+}...O{sup -}) strongly anchored to next-nearest-neighbour framework AlO{sub 4}{sup -} species

  3. Density functional theory of the CuA -like Cu2 S2 diamond core in Cu 2II(NGuaS)2 Cl2.

    Science.gov (United States)

    Witte, M; Gerstmann, U; Neuba, A; Henkel, G; Schmidt, W G

    2016-04-30

    Density functional theory (DFT) calculations with localized as well as plane-wave basis functions are performed for the recently reported dicopper thiolate species Cu2 (NGuaS)2 Cl2 [NGuaS = 2-(1,1,3,3-tetramethylguanidino) benzenethiolate, C11 H16 N3 S] and its bromo derivative [Neuba et al., Angew. Chem. Int. Ed. 2012, 51, 1714.]. For both hybrid and semilocal functionals, the neutral complexes are found to have broken symmetry (BS) character, with electron paramagnetic resonance silent, antiferromagnetically coupled [Cu(2+) …Cu(2+) ] site in which the coupling is driven by super exchange interaction within the Cu2 S2 diamond core. The accurate theoretical description of the geometric structure, however, provides a major challenge for DFT: (i) the multideterminant character of the ground state wave function has to be covered by the BS approach. It requires (ii) metageneralized gradient approximations, that is hybrid functionals with an explicit dependence on the kinetic energy of the individual orbitals: In combination with a dispersion correction, the metafunctional TPSSh results in a CuCu distance close to the experimentally observed value of 2.7 Å. For the negative charge state of the complex, a mixed-valent [Cu(1.5+) …Cu(1.5+) ] electronic structure with a smaller CuCu distance of 2.6 Å is predicted, similar to the value of the CuA site of cytochrome c oxidase.

  4. Characterization of Cu3P phase in Sn3.0Ag0.5Cu0.5P/Cu solder joints

    Institute of Scientific and Technical Information of China (English)

    Jian-xun Chen; Xing-ke Zhao; Xu-chen Zou; Ji-hua Huang; Hai-chun Hu; Hai-lian Luo

    2014-01-01

    This article reports the effects of phosphorus addition on the melting behavior, microstructure, and mechanical properties of Sn3.0Ag0.5Cu solder. The melting behavior of the solder alloys was determined by differential scanning calorimetry. The interfacial micro-structure and phase composition of solder/Cu joints were studied by scanning electron microscopy and energy dispersive spectrometry. Thermodynamics of Cu-P phase formation at the interface between Sn3.0Ag0.5Cu0.5P solder and the Cu substrate was characterized. The results indicate that P addition into Sn3.0Ag0.5Cu solder can change the microstructure and cause the appearance of rod-like Cu3P phase which is distributed randomly in the solder bulk. The Sn3.0Ag0.5Cu0.5P joint shows a mixture of ductile and brittle fracture after shear test-ing. Meanwhile, the solidus temperature of Sn3.0Ag0.5Cu solder is slightly enhanced with P addition.

  5. Comportamento em pastejo e ingestivo de caprinos em sistema silvipastoril

    Directory of Open Access Journals (Sweden)

    Jandson Vieira Costa

    Full Text Available RESUMOFoi avaliado o efeito das diferentes idades de rebrotação da Leucaena leucocephala, associada a gramíneas forrageiras sobre o consumo de forragem e o comportamento de caprinos em sistema silvipastoril. Adotou-se o delineamento inteiramente casualizado com três tratamentos e cinco repetições. Avaliou-se três idades de rebrotação da leucena 45; 60 e 75 dias, com cinco dias de ocupação. O estrato herbáceo foi manejado com idades de 30 dias de rebrotação; foram utilizadas fêmeas mestiças da raça Anglonubiana, cujo comportamento em pastejo foi observado a cada dez minutos, das 8h às 17h. Durante as atividades realizadas pelos animais como ruminação, ócio, deslocamento e pastejo, identificou-se qual a fonte de alimento, se leucena ou estrato herbáceo. A cada duas horas foram aferidas taxa de bocados, levando em consideração o tempo gasto pelos animais para a realização de 20 apreensões. Para a avaliação do consumo foi realizado um teste de pastejo em três dias de ocupação do piquete. O tempo de pastejo foi a atividade mais executada pelos animais com 7,34h e não diferiu significativamente (P>0,05 entre as idades de rebrotação, seguido pelos tempos de deslocamento (1,36h, ruminação (0,51h, e ócio (0,39h. Não houve diferença significativa (P>0,05 para a taxa de bocados, massa de forragem total, taxa de ingestão, e consumo diário. O manejo das idades de rebrotação da leucena em sistema silvipastoril contribui de forma satisfatória para a produção de forragem de leucena e de gramíneas forrageiras e não interfere no comportamento em pastejo e ingestivo de caprinos.As gramíneas constituem-se no componente de maior preferência da dieta dos caprinos no sistema silvipastoril: leucena-gramíneas forrageiras.

  6. Thermal stability of Py/Cu and Co/Cu giant magnetoresistance (GMR) multilayer systems

    Energy Technology Data Exchange (ETDEWEB)

    Vovk, Vitaliy

    2007-07-01

    NiFe/Cu and Co/Cu multilayer systems have been studied regarding the mechanisms of thermal degradation of the giant magnetoresistance effect (GMR). The different thermodynamics of the studied systems results in different mechanisms of the GMR degradation as shown by highest resolution nanoanalysis using the three dimensional wide angle tomographic atom probe. According to the TAP analysis, GMR deterioration in Py/Cu system occurs due to the broadening of the layer interfaces observed at 250 C. In contrast, due to the strong demixing tendency, Co/Cu multilayers remain stable up to 450 C. At higher temperatures ferromagnetic bridging of the neighboring Co layers takes place leading to the GMR breakdown. In both Py/Cu and Co/Cu systems recrystallization is induced at 350-450 C, which is accompanied by a change in the crystallographic orientation from <111> to <100> wire texture. The reaction may be utilized to produce GMR sensor layers of remarkable thermal stability. Although the systems of interest are equivalent in respect of the observed phenomenon, the Ni{sub x}Fe{sub 1-x}/Cu system is chosen for a detailed analysis because it allows a precise control of the lattice constant by varying the Fe content in the Ni{sub x}Fe{sub 1-x} layer. It is shown that the crystallographic reorientation is triggered by the minimization of lattice mismatch elastic energy. Moreover, the counteraction between the elastic and interfacial energy minimizations exerts a critical influence on the recrystallization probability. (orig.)

  7. Wurtzite CuInS₂ and CuInxGa₁-xS₂ nanoribbons: synthesis, optical and photoelectrical properties.

    Science.gov (United States)

    Li, Qiang; Zhai, Lanlan; Zou, Chao; Huang, Xusheng; Zhang, Lijie; Yang, Yun; Chen, Xi'an; Huang, Shaoming

    2013-02-21

    Single crystalline wurtzite ternary and quaternary semiconductor nanoribbons (CuInS(2), CuIn(x)Ga(1-x)S(2)) were synthesized through a solution-based method. The structure and composition of the nanoribbons were characterized by X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), the corresponding fast Fourier transform (FFT) and nanoscale-resolved elemental mapping. Detailed investigation of the growth mechanism by monitoring the structures and morphologies of the nanoribbons during the growth indicates that Cu(1.75)S nanocrystals are formed first and act as a catalyst for the further growth of the nanoribbons. The high mobility of Cu(+) promotes the generation of Cu(+) vacancies in Cu(1.75)S, which will facilitate the diffusion of Cu, In or Ga species from solution into Cu(1.75)S to reach supersaturated states. The supersaturated species in the Cu(1.75)S catalyst, Cu-In-S and Cu-In-Ga-S species, start to condense and crystallize to form wurtzite CuInS(2) or CuIn(x)Ga(1-x)S(2) phases, firstly resulting in two-sided nanoparticles. Successive crystallizations gradually impel the Cu(1.75)S catalyst head forward and prolong the length of the CuInS(2) or CuIn(x)Ga(1-x)S(2) body, forming heterostructured nanorods and thus nanoribbons. The optical band gaps of CuIn(x)Ga(1-x)S(2) nanoribbons can be continuously adjusted between 1.44 eV and 1.91 eV, depending on the Ga concentration in nanoribbons. The successful preparation of those ternary and quaternary semiconductor nanoribbons provide us an opportunity to study their photovoltaic properties. The primary photoresponsive current measurements demonstrate that wurtzite CuIn(x)Ga(1-x)S(2) nanoribbons are excellent photoactive materials. Furthermore, this facile method could open a new way to synthesize other various nano-structured ternary and quaternary semiconductors, such as CuInSe(2) and CuIn(x)Ga(1-x)Se(2), for applications in solar cells and other fields.

  8. Comparison of Two Kinds of 64Cu Labelled Octreotide Analogues

    Directory of Open Access Journals (Sweden)

    HAN Zhen-yi1;LIANG Ji-xin1;HU Ji2;LUO Hong-yi1;QING Jing2;CHEN Yu-qing2;LI Guang2;LI Hong-yu1,2

    2016-10-01

    Full Text Available Octreotide analogues DOTA-TOC and DOTA-TATE were labeled with 64Cu. The influences of the ratio of peptide mass to 64Cu activity, pH value, temperature and reaction time on labeling yield were investigated. The optimum labeling was determined. In vitro stability tests in saline and 10% bovine serum had been carried out. Biodistribution of the two radiolabelled compounds in normal mice and Micro PET imaging in nude mice bearing U87MG tumor had been evaluated. The results showed that the labeling yields of 64Cu-DOTA-TOC and 64Cu-DOTA-TATE were higher than 95%. Two kinds of octreotide analogues labeled with 64Cu were quite stable in saline and decomposed slowly in 10% bovine serum at 37 ℃. Biodistribution results in normal mice showed that two 64Cu labelled tracers had similar profiles. Both of the compounds washed out from the blood quickly. High uptake of radioactivity in liver and kidneys indicated the tracers were excreted via both hepatobiliary system and renal system. At the same time, compared to 64Cu-DOTA-TOC, higher radioactivity accumulation of 64Cu-DOTA-TATE in liver and kidneys was observed. Micro PET images of U87MG tumor-bearing nude mice with 64Cu-DOTA-TOC and 64Cu-DOTA-TATE showed the tumors very clearly. The radioactivity uptake of 64Cu-DOTA-TATE in tumor was higher than that of 64Cu-DOTA-TOC. This work has paved the way for further preclinical and clinical application of 64Cu-DOTA-TOC and 64Cu-DOTA-TATE as PET tumor imaging agents.

  9. Negative-Pressure Cavitation Extraction of Four Main Vinca Alkaloids from <em>Catharanthus em>roseus> Leaves

    Directory of Open Access Journals (Sweden)

    Yuangang Zu

    2012-07-01

    Full Text Available In the present study, an improved method termed negative-pressure cavitation extraction (NPCE followed by reverse phase high-performance liquid chromatography (RP-HPLC was developed for the extraction and quantification of vindoline (VDL, catharanthine (CTR, vincristine (VCR and vinblastine (VLB from <em>Catharanthus roseus em>leaves. The optimized method employed 60-mesh particles, 80% ethanol, a negative pressure of −0.075 MPa, a solid to liquid ratio of 1:20, 30 min of extraction and three extraction cycles. Under these optimized conditions, the extraction yields of VDL, CTR, VCR and VLB are 0.5783, 0.2843, 0.018 and 0.126 mg/g DW, respectively. These extraction yields are equivalent to those from the well-known ultrasonic extraction method and higher than the yields from maceration extraction and heating reflux extraction. Our results suggest that NPCE-RP-HPLC represents an excellent alternative for the extraction and quantification of vinca alkaloids for pilot- and industrial-scale applications.

  10. Characterization of CuInS2 thin films prepared by sulfurization of Cu-In precursor

    Institute of Scientific and Technical Information of China (English)

    YAN You-hua; LIU Ying-chun; FANG Ling; ZHU Jing-sen; ZHAO Hai-hua; LI De-ren; LU Zhi-chao; ZHOU Shao-xiong

    2008-01-01

    CuInS2 thin films were prepared by sulfurization of Cu-In precursors. The influences of the depo