排序方式: 共有63条查询结果,搜索用时 15 毫秒
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Fernandes Felipe Hugo Alencar Boylan Fabio Salgado Hérida Regina Nunes 《Journal of Thermal Analysis and Calorimetry》2018,132(3):1923-1931
Journal of Thermal Analysis and Calorimetry - The solid–liquid phase equilibrium for binary system of 2,4,6-trimethylphenol (TMP) and 2,5-dimethylphenol (DMP) was built by differential... 相似文献
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A. Alencar S. Azevedo M. Machado 《Applied Physics A: Materials Science & Processing》2011,102(3):583-591
Interaction of one iron atom with pristine zigzag boron nitride nanotubes with different diameters, ranging from (8,0) to
(12,0), have been investigated using density functional theory calculations. Departing from four initial configurations, considering
each of them interacting with the tubes’ walls either from inside or outside, we have analyzed the adsorbate migration to
the most favorable positions together with the related binding energies and the equilibrium distances as well as the electronic
structure of the final systems. It was observed that the smaller the radius of the tube the lower is the binding energy for
all studied structures, and also that the inner configuration is more stable than the outer one for small radius. For the
preferred position for the iron atom, it was seen that it varies according to the starting configuration and that the iron-first-nitrogen-neighbor
bond length works as a constraint in determining the most favorable position for the adsorbate. Finally, for the electronic
structure, it was observed that the presence of the dopant introduces localized levels at the band gap of the nanotubes and
that those levels are mostly related to the orbitals 3d and 4s of the iron atom. For the inside case, as a consequence of
higher hybridization and a confinement effect, the gap closure is more pronounced for small diameter tubes. For all studied
structures, it was observed a net-spin-polarization equal to 4 μ
B. 相似文献
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Finite mixture modeling of censored and missing data using the multivariate skew-normal distribution
de Alencar Francisco H. C. Galarza Christian E. Matos Larissa A. Lachos Victor H. 《Advances in Data Analysis and Classification》2022,16(3):521-557
Advances in Data Analysis and Classification - Finite mixture models have been widely used to model and analyze data from a heterogeneous populations. Moreover, data of this kind can be missing or... 相似文献
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This study uses the entropy method to overcome the problem with estimating income distribution dynamics in the absence of data that allow identifying and following up economic units over time. The axiomatic mobility approach (Shorrocks, 1976) [1] and the tools developed by Aebi et al. (1999) [2] were considered. This strategy assumes that income mobility between two time periods is governed by a first-order Markov process. In this context, the measurement of the dynamics of income distribution will be equivalent to fitting cell probabilities for contingency tables, where only marginal distributions are observed. Results suggest that Brazil has low intragenerational income mobility, indicating that its social framework is relatively rigid. In other words, the income class in which an individual is inserted will determine his/her future social position. 相似文献
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A hypersurface M
n
immersed in a space form is r-minimal if its (r + 1)
th
-curvature (the (r + 1)
th
elementary symmetric function of its principal curvatures) vanishes identically. Let W be the set of points which are omitted by the totally geodesic hypersurfaces tangent to M. We will prove that if an orientable hypersurface M
n
is r-minimal and its r
th
-curvature is nonzero everywhere, and the set W is nonempty and open, then M
n
has relative nullity n − r. Also we will prove that if an orientable hypersurface M
n
is r-minimal and its r
th
-curvature is nonzero everywhere, and the ambient space is euclidean or hyperbolic and W is nonempty, then M
n
is r-stable. 相似文献
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Renata leite Tavares Maria Helena Araújo de Vasconcelos Maria Letícia da Veiga Dutra Aline Barbosa DOliveira Marcos dos Santos Lima Mirian Graciela da Silva Stiebbe Salvadori Ramon de Alencar Pereira Adriano Francisco Alves Yuri Mangueira do Nascimento Josean Fechine Tavares Omar Guzman-Quevedo Jailane de Souza Aquino 《Molecules (Basel, Switzerland)》2020,25(23)
This study evaluated the effect of Mucuna pruriens (MP) administration on neuroinflammation and behavioral and murinometric parameters in obese rats. Proximate composition, oligosaccharide and phenolic compound profile of MP were determined. Wistar adult male rats were randomized into healthy (HG) and obese group (OG). The HG consumed a control chow diet while OG consumed a cafeteria diet for eight weeks. Then, they were subdivided into: Healthy (HG); Healthy with MP administration (HGMP); Obese (OG); Obese with MP administration (OGMP), with the consumption of the respective diets remaining for another eight weeks, in addition to gavage with MP extract to supplemented groups (750 mg/kg weight). MP presented a composition rich in proteins and phenolic compounds, especially catechin, in addition to 1-kestose and levodopa. Supplementation reduced food intake, body weight, and thoracic and abdominal circumferences in obese rats. MP showed anxiolytic and antidepressant effects and reduced morphological damage and expression of interleukin 6 in the hippocampus of obese rats. MP treatment showed satietogenic, slimming, anxiolytic and antidepressant effects, besides to minimizing hippocampal neuroinflammation in obese rats. Our results demonstrated the potential anti-obesity of MP which are probably related to the high content of bioactive compounds present in this plant extract. 相似文献