959 resultados para NORMAL STATE PROPERTIES


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The coordination compounds [Ni(μ-mal)(apy)2(H 2O)]·2.8H2O (1), [Mn(μ-mal)(H2O) 2] (2), (apyH)2[Cu(μ-mal)2] (3) and (apyH)2[Co(mal)2(H2O)2] (4) (mal = malonate, apy = p-aminopyridine) have been synthesized and characterized by elemental analysis, vibrational spectroscopy, single crystal X-ray diffraction and magnetometry. With exception of 4, the malonate group acts as bridging ligand leading to the formation of one-dimensional polymeric chains. In compound 1 it was observed the coordination of the p-aminopyridine in the axial positions of the distorted octahedral coordination sphere. The solid-state structure exhibits a high complex 3D network formed by several supramolecular interactions. Magnetic properties were determined for all members of the series and indicate that the materials behave are normal paramagnets, except the Mn polymer 2 which exhibits an antiferromagnetic ground state. © 2013 Elsevier Ltd. All rights reserved.

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The gerbil is a rodent considered a good model for studies of prostatic morphophysiology under different experimental conditions. Studies involving castration and steroidal blockers of aged gerbils showed that the glandular epithelium persists after long-term therapy, preventing the organ atrophy. Thus, the objective of this study was to evaluate the phenotypic characteristics and behavior of prostatic epithelial cells that remained after different periods of hormone ablation in aged gerbils. The identification of elements that influenced the survival of this cell type was performed by morphometric, nuclear phenotypes, ultrastructural and immune histochemical analysis. The most significant responses to treatment, by analyzing morphometric features, were observed during the first three time points (day 1, day 3, and day 7), after which there appeared to be an adjustment of the gland to the hormone ablation. All treatments led to changes in the state of chromatin condensation, DNA methylation pattern and phenotypic changes indicated cell senescence. Additionally, an increase in the basal cells seemed to guarantee self-renewal properties to the epithelium. These data indicate that changes occur at many levels, including gene expression and nuclear architecture in the epithelial cells, when aging and steroidal blockade are associated. These aspects are important when considering castration-resistant prostate cancer, a malignant tumor posing difficult therapeutic intervention. © 2013 Elsevier GmbH. All rights reserved.

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The influence of current density, at the interval 5-100 mA cm-2, on the structural and magnetic properties of electrodeposited (Co 100-xNix)100-yWy alloys (x = 23-33.5 at. % Ni, y = 1.7-7.3 at. % W) was studied from a glycine-containing bath. W-content decreases with the increase of the current density magnitude. X-ray data have shown stabilization of hexagonal close packed, face centered cubic or a mixture of these structures by modulating the applied cathodic current density, for values lower than 50 mA cm-2. Two structural phase transitions were observed: one from hexagonal close packed to face centered cubic structural transition occurring for a current density of 20 mA cm -2, and another one, from cubic crystalline phase to amorphous state, which happens for values higher than 50 mA cm-2. These structural phase transitions seem to be associated with the W-content as well as average crystalline grain sizes that reduce with increasing the current density value. The grain size effect may explain the face centered cubic stabilization in Co-rich CoNiW alloys, which was initially assumed to be basically due to H-adsorption/incorporation. Magnetic properties of Co-rich CoNiW alloys are strongly modified by the current density value; as a result of the changes on the W-content and their structural properties© 2013 Elsevier B.V. All rights reserved.

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The nonlinear (NL) optical properties of glassy xBi2O 3-(1-x) GeO2 with x = 0.72 and 0.82 were investigated. The experiments were performed with lasers at 800 nm (pulses of 150 fs) and 532 nm (pulses of 80 ps and 250 ns). Using the Kerr gate technique, we observed that the NL response of the samples at 800 nm is faster than 150 fs. NL refraction indices, | n 2 | ≈ 5 × 10-16 cm2/W, and two-photon absorption coefficients, α 2, smaller than 0.03 cm/GW, were measured at 800 nm. At 532 nm, we measured the NL transmittance of the samples. From the results obtained, we determined α 2 ≈1 cm/GW and excited-state absorption cross-sections of ≈10-22 cm2 due to free-carriers. © 2013 AIP Publishing LLC.

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The stagnant effective thermal conductivities (K0) of sugar cane bagasse (SCB), wheat bran (WB), orange pulp and peel (OPP) and their combination (weight proportion 1:2:2 SCB/OPP/WB) were obtained using the line heat source method. These solid materials were applied to pectinase production via solid-state fermentation. The moisture content ranged from 4 to 80% (w.b.). A conduction mechanism through the porous media was observed, along with conduction through a liquid film and contact thermal resistance between the samples and the probe. K0 was low for intermediate moisture contents and approached the molecular conductivity of water for high moisture contents. © 2013 Copyright Taylor and Francis Group, LLC.

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We consider dynamical properties for an ensemble of classical particles confined to an infinite box of potential and containing a time-dependent potential well described by different nonlinear functions. For smooth functions, the phase space contains chaotic trajectories, periodic islands and invariant spanning curves preventing the unlimited particle diffusion along the energy axis. Average properties of the chaotic sea are characterised as a function of the control parameters and exponents describing their behaviour show no dependence on the perturbation functions. Given invariant spanning curves are present in the phase space, a sticky region was observed and show to modify locally the diffusion of the particles. © 2013 Elsevier B.V.

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We study consistently the pion's static observables and the elastic and γ* γ → π0 transition form factors within a light-front model. Consistency requires that all calculations are performed within a given model with the same and single adjusted length or mass-scale parameter of the associated pion bound-state wave function. Our results agree well with all extent data including recent Belle data on the γ* γ → π0 form factor at large q2, yet the BaBar data on this transition form factor resists a sensible comparison. We relax the initial constraint on the bound-state wave function and show the BaBar data can partially be accommodated. This, however, comes at the cost of a hard elastic form factor not in agreement with experiment. Moreover, the pion charge radius is about 40 % smaller than its experimentally determined value. It is argued that a decreasing charge radius produces an ever harder form factor with a bound-state amplitude difficultly reconcilable with soft QCD. We also discuss why vector dominance type models for the photon-quark vertex, based on analyticity and crossing symmetry, are unlikely to reproduce the litigious transition form factor data. © 2013 Springer-Verlag Wien.

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This study was performed in order to determine the effect of the addition of different concentrations of glycerol and ethanol over functional and structural properties of zein-oleic acid films. Films were prepared from zein and oleic acid formulations, containing: 0, 10, 20 and 30% (w/w) of glycerol as plasticizer and 75, 80, 85, 90 and 95% (v/v) of ethanol as zein solvent. Water vapor permeability (WVP) at 4 and 24 C, opacity, water solubility and structural behavior of the film were assessed. The film water barrier properties, WVP and water solubility, were increased when higher ethanol concentration and lower glycerol concentration were used. Furthermore, WVP at 4 C was lower than WVP at 24 C due to the crystalline solid state of oleic acid at lower temperatures. Likewise, opacity, homogeneity and structure of the composite film were improved as ethanol increased and glycerol lowered. © 2013 Elsevier B.V. All rights reserved.

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Pós-graduação em Educação Escolar - FCLAR

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Pós-graduação em Educação - FFC

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Pós-graduação em Desenvolvimento Humano e Tecnologias - IBRC

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A presente pesquisa tem o objetivo de analisar o currículo da Escola Normal do Pará, mais especificamente no que se refere às Ciências Naturais que constaram em sua estrutura, desde 1870 até 1930. Esta instituição foi criada em 1871 com o fim de formar professores para atuarem na instrução primária. Situada em Belém, que era o centro mais urbanizado da região, a Escola Normal estava entre as principais instituições da instrução pública paraense. As Ciências Naturais fizeram parte do primeiro currículo da Escola Normal do Pará, sendo elas a Física e a Química, contudo deixaram de fazer parte em 1874. O retorno das Ciências da Natureza se deu durante a Primeira República, por meio da Física, da Química e da História Natural, as quais se consolidaram ao longo deste período. A pesquisa analisa esta trajetória partindo do pressuposto que o currículo é um artefato social e histórico, sujeito a flutuações e que refletiu e continua a refletir as relações de poder envolvidas nos processos de seleção e transmissão cultural. Outra perspectiva analítica deste estudo considera o currículo como um meio de difusão científica, que também determina os modos que esta deve ocorrer. Sobre a difusão científica, parte-se do princípio que este processo não é simétrico, que os saberes científicos são criados em centros mais fortes e que ao serem difundidos para a periferia tem que interagir com a cultura que os recebe, os quais são conformados e modificados, sendo-lhes agregados valores diferentes dos que possuem nos países de centro. Assim, a pesquisa divide-se em três capítulos. O primeiro tem o objetivo de ver o desenvolvimento das Ciências Naturais no currículo do município do Rio de Janeiro, entre 1850 e 1890, que era a sede do governo central e o principal centro difusor de idéias para outras localidades do país, tanto em termos de educação quanto em outras áreas da administração pública. Com isso, analisa-se o desenvolvimento curricular do ensino primário, secundário e normal do Rio, mais especificamente em relação as Ciências Naturais, a partir das Reformas Coutto Ferraz (1854), Leôncio de Carvalho (1879) e Benjamin Constant (1890), as quais determinaram mudanças no currículo e na educação de modo geral. O segundo capítulo faz um resgate do desenvolvimento curricular da instrução pública primária e secundária paraense (1840-1870), isto para ver qual era o cenário curricular da instrução pública as vésperas da criação da Escola Normal, o que permite perceber e analisar que mudanças foram introduzidas por esta instituição neste contexto. O terceiro capítulo, num primeiro momento, revê a trajetória da Escola Normal do Pará e, num segundo momento, analisa-se o desenvolvimento do currículo normalista do Pará em relação as Ciências Naturais, de modo que é evidenciado a emergência e solidificação dos saberes científicos, tal como a distribuição de carga-horária em relação aos outros saberes e as próprias ciências constituintes do currículo.