992 resultados para Driven 2-level Atoms


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The article reports density measurements of dipropyl (DPA), dibutyl (DBA) and bis(2-ethylhexyl) (DEHA) adipates, using a vibrating U-tube densimeter, model DMA HP, from Anton Paar GmbH. The measurements were performed in the temperature range (293 to 373) K and at pressures up to about 68 MPa, except for DPA for which the upper limits were 363 K and 65 MPa, respectively. The density data for each liquid was correlated with the temperature and pressure using a modified Tait equation. The expanded uncertainty of the present density results is estimated as 0.2% at a 95% confidence level. No literature density data at pressures higher than 0.1 MPa could be found. DEHA literature data at atmospheric pressure agree with the correlation of the present measurements, in the corresponding temperature range, within +/- 0.11%. The isothermal compressibility and the isobaric thermal expansion were calculated by differentiation of the modified Tait correlation equation. These two parameters were also calculated for dimethyl adipate (DMA), from density data reported in a previous work. The uncertainties of isothermal compressibility and the isobaric thermal expansion are estimated to be less than +/- 1.7% and +/- 1.1%, respectively, at a 95% confidence level. Literature data of isothermal compressibility and isobaric thermal expansivity for DMA have an agreement within +/- 1% and +/- 2.4%, respectively, with results calculated in this work. (C) 2014 Elsevier B.V. All rights reserved.

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fac-[MBr(CO)(3)(pypzH)] (M = Mn, Re; pypzH = (3-(2-pyridyl) pyrazole) complexes are prepared from fac[ MBr(CO)(3)(NCMe)(2)] and pypzH. The result of their deprotonation depends on the metallic substrate: the rhenium complex affords cleanly the bimetallic compound [fac-{Re(CO)(3)(mu(2)-pypz)}] 2 (mu(2)-pypz = mu(2)-3-(2pyridyl-. 1N) pyrazolate-2. 1N), which was crystallographically characterized, whereas a similar manganese complex was not detected. When two equivalents of pyridylpyrazolate are used, polymetallic species [fac-M(CO) 3(mu(2)-pypz)(mu(3)-pypz) M'] (mu(3)-pypz = mu(3)-3-(2-pyridyl-kappa N-1) pyrazolate-1 kappa 2N, N: 2. 1N:; M = Mn, M' = Li, Na, K; M = Re, M' = Na) are obtained. The crystal structures of the manganese carbonylate complexes were determined. The lithium complex is a monomer containing one manganese and one lithium atom, whereas the sodium and potassium complexes are dimers and reveal an unprecedented coordination mode for the bridging 3-(2-pyridyl) pyrazolate ligand, where the nitrogen of the pyridyl fragment and the nitrogen-1 of pyrazolate are chelated to manganese atoms, and each nitrogen-2 of pyrazolate is coordinated to two alkaline atoms. The polymetallic carbonylate complexes are unstable in solution and evolve spontaneously to [fac-{Re(CO) 3(mu(2)-pypz)}](2) or to the trimetallic paramagnetic species [MnII(mu(2)-pypz) 2{fac-{MnI(CO) 3(mu(2)-pypz)}(2)}]. The related complex cis-[MnCl2(pypzH)(2)] was also synthesized and structurally characterized. The electrochemical behavior of the new homo-and heteropolymetallic 3-(2-pyridyl) pyrazolate complexes has been studied and details of their redox properties are reported.

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In Part I of the present work we describe the viscosity measurements performed on tris(2-ethylhexyl) trimellitate or 1,2,4-benzenetricarboxylic acid, tris(2-ethylhexyl) ester (TOTM) up to 65 MPa and at six temperatures from (303 to 373)K, using a new vibrating-wire instrument. The main aim is to contribute to the proposal of that liquid as a potential reference fluid for high viscosity, high pressure and high temperature. The present Part II is dedicated to report the density measurements of TOTM necessary, not only to compute the viscosity data presented in Part I, but also as complementary data for the mentioned proposal. The present density measurements were obtained using a vibrating U-tube densimeter, model DMA HP, using model DMA5000 as a reading unit, both instruments from Anton Paar GmbH. The measurements were performed along five isotherms from (293 to 373)K and at eleven different pressures up to 68 MPa. As far as the authors are aware, the viscosity and density results are the first, above atmospheric pressure, to be published for TOTM. Due to TOTM's high viscosity, its density data were corrected for the viscosity effect on the U-tube density measurements. This effect was estimated using two Newtonian viscosity standard liquids, 20 AW and 200 GW. The density data were correlated with temperature and pressure using a modified Tait equation. The expanded uncertainty of the present density results is estimated as +/- 0.2% at a 95% confidence level. Those results were correlated with temperature and pressure by a modified Tait equation, with deviations within +/- 0.25%. Furthermore, the isothermal compressibility, K-T, and the isobaric thermal expansivity, alpha(p), were obtained by derivation of the modified Tait equation used for correlating the density data. The corresponding uncertainties, at a 95% confidence level, are estimated to be less than +/- 1.5% and +/- 1.2%, respectively. No isobaric thermal expansivity and isothermal compressibility for TOTM were found in the literature. (C) 2014 Elsevier B.V. All rights reserved.

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Conferência: CONTROLO’2012 - 16-18 July 2012 - Funchal

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Relatório de Estágio apresentado à Escola Superior de Educação de Lisboa para obtenção de grau de mestre em Ensino do 1.º e 2.º Ciclo do Ensino Básico

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Relatório de Estágio apresentado à Escola Superior de Educação de Lisboa para obtenção de grau de mestre em Ensino do 1º e 2º Ciclo do Ensino Básico

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A schistosomiasis control program was implemented between 1974/87 in Peri-Peri,. MG (622 inhabitants). Molluscicide (niclosamide) was applied at three monthly intervals in water sources with Biomphalaria glabrata, and individuals eliminating Schistosoma mansoni eggs in the feces were treated annually with oxamniquine. From 1974 to 1983 the control measures were undertaken by staff of the "René Rachou" Research Center FIOCRUZ (CPqRR), and from 1984 to 1987 these measures were included in the Capim Branco basic health network activities. During both periods, the prevalence, incidence, intensity of infection and hepatosplenic form as well as the number of infected snails decreased significantly. The prevalence decreased from 43.5 to 4.4%, the incidence from 19.0 to 2.9%, the overall intensity of S. mansoni from 281 to 87 and of the hepatosplenic form from 5.9 to 0.0%. The results obtained suggest that the municipal management of control measures was as effective as the vertical program conducted by CPqRR staff.

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A utilização de aplicações Web 2.0 no processo ensino/aprendizagem tem vindo a intensificar-se nos últimos tempos, mais por iniciativas individuais de docentes e estudantes do que por estratégia das Instituições de Ensino. Este artigo apresenta um projecto já em curso que consiste na implementação de uma plataforma de criação de ambientes de aprendizagem controlados pelos estudantes, integrando aplicações Web 2.0 e sistemas de gestão de conteúdos. A plataforma permitirá a utilização segura de conteúdos criados em aplicações Web 2.0, no processo de avaliação, possibilitando a sua publicação na infra-estrutura controlada pela Instituição de Ensino Superior, contribuindo assim para a adequação do binómio ensino/aprendizagem ao novo paradigma implicado no processo de Bolonha.

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RESUMO - A diabetes mellitus é considerada um flagelo à escala mundial, não apenas por atingir milhões de pessoas, mas também porque se tem verificado um aumento da sua prevalência e, consequente-mente, das suas complicações crónicas, que se traduzem no aumento dos gastos em saúde e, sobretudo, em sofrimento das pessoas com diabetes, seus familiares e comunidade. A prevenção das complicações crónicas da diabetes reside, sobretudo, na adopção de comporta-mentos saudáveis que, no dia-a-dia, se traduzem em competência no autocuidado. Assim, será importante conhecer em que medida o sentido de coerência – característica pessoal entendida como influenciadora das estratégias utilizadas face aos acontecimentos originadores de stress, com repercussões na saúde mental, bem como na saúde física – pode determinar a escolha de comportamentos de saúde e, por tal, possa considerar-se como um aspecto sobre o qual os pro-fissionais de saúde poderão investir em prole do seu fortalecimento e, consequentemente, garantir a facilitação do processo de adopção de comportamentos saudáveis. De acordo com o estudo transversal exploratório retrospectivo proposto ambiciona-se conhecer a relação entre o nível de sentido de coerência e o nível de autocuidado e de controlo metabólico, das pessoas com diabetes de tipo 2. Para tal investigação reconhece-se a pertinência da aplica-ção da escala de avaliação do sentido de coerência – Questionário Orientação para Viver (Nunes, 1999), da escala de avaliação do autocuidado com a diabetes – Escala de Avaliação das Activida-des de Autocuidado com a Diabetes (Bastos, Severo e Lopes, 2007) e do Formulário de Controlo Metabólico na Diabetes (European Society of Cardiology e European Association for the Study of Diabetes cit. por Direcção-Geral da Saúde, 2007), numa amostra constituída por 391 pessoas com diabetes de tipo 2, seleccionadas por amostragem aleatória estratificada proporcional, de entre os utentes inscritos nas 33 instituições de Cuidados de Saúde Primários, do distrito de Viana do Castelo --------------------------- ABSTRACT - Diabetes mellitus is considered a global scourge, not only for reaching millions of people, but also because there has been an increase in its prevalence and, consequently, its chronic complications, which translate into increased spending on health and especially in the suffering of people with diabetes, their families and community. The prevention of chronic complications of diabetes includes adoption healthy behaviors that on the day to day, translate into competence in self-care. Therefore it is important to know how far the sense of coherence – understood as influential personal characteristic of the strategies used by the events originators of stress, affecting the mental health and physical health – may determine the choice of health behaviors and, as such, can be considered as an aspect about which health pro-fessionals will invest in strengthening their offspring and thus ensure the facilitation of the process of adopting healthy behaviors. According to the proposed retrospective exploratory cross-sectional study aims to discover the relationship between the level of sense of coherence and level of self-care and metabolic control on people with type 2 diabetes. For this research recognizes the appropriateness of applying the rating scale of sense of coherence – Questionário Orientação para Viver (Nunes, 1999), the rating scale of self-care in diabetes – Escala de Avaliação das Actividades de Autocuidado com a Di-abetes (Bastos, Severo and Lopes, 2007) and the Formulário de Controlo Metabólico na Diabetes (European Society of Cardiology and European Association for the Study of Diabetes cit. por Di-recção-Geral da Saúde, 2007), a sample of 391 people with type 2 diabetes, selected by propor-tional stratified random sampling from among registered users in 33 institutions of Primary Health Care, on district of Viana do Castelo.

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Thesis submitted to Faculdade de Ciências e Tecnologia from Universidade Nova de Lisboa in partial fulfillment of the requirements for the obtention of the degree of Master of Science in Biotechnology

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Dissertation to obtain a Master Degree in Biotechnology

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Trabalho apresentado no âmbito do Mestrado em Engenharia Informática, como requisito parcial para obtenção do grau de Mestre em Engenharia Informática

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The aim of this study was to verify the possibility to use a polarized graphite electrode as an electron donor for the reductive dechlorination of 1,2-dichloroethane, an ubiquitous groundwater contaminant. The rate of 1,2-DCA dechlorination almost linearly increased by decreasing the set cathode potential over a broad range of set cathode potentials (i.e., from −300 mV to −900 mV vs. the standard hydrogen electrode). This process was primarily dependent on electrolytic H2 generation. On the other hand, reductive dechlorination proceeded (although quite slowly) with a very high Coulombic efficiency (near 70%) at a set cathode potential of −300 mV, where no H2 production occurred. Under this condition, reductive dechlorination was likely driven by direct electron uptake from the surface of the polarized electrode. Taken as a whole, this study further extends the range of chlorinated contaminants which can be treated with bioelectrochemical systems.

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Com base no modelo de Resposta à Intervenção (RtI), este estudo centrouse em três objetivos: construir um instrumento vocacionado para a determinação do nível de competências fundamentais, do 1º ao 6º anos, na disciplina de Matemática; avaliar o valor preditivo do instrumento sobre a necessidade de intervenção; examinar o efeito de uma intervenção planeada com base na avaliação diagnóstica desse instrumento. Para dar resposta ao primeiro e segundo objetivos foram consideradas duas amostras de conveniência: a primeira, constituída por 5 docentes, avaliou a versão teste do instrumento e a segunda, constituída por 6 docentes, avaliou a sua versão final (perfazendo um total de 75 alunos). Recorrendo ao método kmeans, os resultados mostraram que o instrumento é de útil e fácil aplicação, permitindo aos docentes avaliarem e identificarem o grupo de desempenho a que pertence cada aluno, em relação à média dos resultados da respetiva turma. Relativamente ao terceiro objetivo, foi constituída uma amostra de 7 alunos de uma turma do 4º ano. A intervenção decorreu ao longo de 11 semanas, com 2 sessões semanais, cuja duração variou entre 10 a 35 minutos. Para avaliar os efeitos da intervenção, foi realizado um pré e um pós-teste, assim como 2 sessões de avaliação intermédia (checkpoints), tendo-se recorrido ao teste não paramétrico de Friedman e ao teste de Wilcoxon, para avaliar a significância das diferenças entre os tempos e os níveis de suporte, para o aluno resolver a tarefa com sucesso, respetivamente. Os resultados mostraram diferenças estatiscamente significativas, particularmente entre as duas avaliações intermédia consideradas.