Navegação Ciências Exatas e da Terra por Título
Resultados 2236-2255 de 5955
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Gráficos na escola
(1992) [Artigo de periódico] -
Grain growth from homogeneous initial conditions : anomalous grain growth and special scaling states
(1995) [Artigo de periódico]We used the large-Q Potts model on a two-dimensional lattice to study the evolution of the disordered cluster developed from a perfect hexagonal lattice with a single defect. The distribution functions were not stable, ... -
Granger causality and time series regression for modelling the migratory dynamics of infuenza into Brazil
(2023) [Artigo de periódico]In this work we study the problem of modelling and forecasting the dynamics of the infuenza virus in Brazil at a given month, from data on reported cases and genetic diversity collected from previous months, in other ... -
Granular superconductivity ina Ca-doped YBa/sub 2/Cu/sub 3/O/sub 7-σ single crystal : role of divalent impurities and the effect of applied field on the grain coupling
(2007) [Artigo de periódico]We investigate the effect of the divalent Ca atoms at the trivalent Y site of YBa2Cu3O7−δ on the magnetoconductivity and magnetic irreversibility of single crystals and a polycrystalline sample. The magnetic irreversibility ... -
Graphical models and point pattern matching
(2006) [Artigo de periódico]This paper describes a novel solution to the rigid point pattern matching problem in Euclidean spaces of any dimension. Although we assume rigid motion, jitter is allowed. We present a noniterative, polynomial time algorithm ... -
A graphite thermal evaporation source for aluminum
(1990) [Artigo de periódico] -
Green-Function Method for a Mixed-Valence Hamiltonian
(1984) [Artigo de periódico]A Green-function diagrammatic method is utilized to calculate the occupation number of a narrow (j) band in a mixed-valence system. The method is a generalization of the Hubbard-1 approximation for a two-band Hamiltonian. ... -
Green method by diffuse reflectance infrared spectroscopy and spectral region selection for the quantification of sulphamethoxazole and trimethoprim in pharmaceutical formulations
(2016) [Artigo de periódico]An alternative method for the quantifi cation of sulphametoxazole (SMZ) and trimethoprim (TMP) using diffuse refl ectance infrared Fourier-transform spectroscopy (DRIFTS) and partial least square regression (PLS) was ... -
Ground- and excited-state scattering potentials for the stopping of protons in an electron gas
(2019) [Artigo de periódico]The self-consistent electron–ion potential V(r) is calculated for H+ ions in an electron gas system as a function of the projectile energy to model the electronic stopping power for conduction-band electrons. The results ... -
Ground-based observation of ZZ Ceti stars and the discovery of four new variables
(2019) [Artigo de periódico]We perform ground-based photometric observations of 22 DA white dwarf stars, 10 already known ZZ Cetis and 12 candidates with atmospheric parameters inside the classical instability strip. We report on the discovery of ... -
Ground states of spin-1 bosons in asymmetric double wells
(2015) [Artigo de periódico]In this work we investigate the different states of a system of spin-1 bosons in two potential wells connected by tunneling, with spin-dependent interaction. The model utilizes the well-known Bose-Hubbard Hamiltonian, ... -
Group velocity of obliquely propagating Alfvén waves in a magnetized dusty plasma
(2022) [Artigo de periódico]In this work, we investigate the characteristics of the group velocity of obliquely propagating Alfvén in a dusty plasma typical of a stellar wind. The dispersion relation is derived with the aid of the kinetic theory for ... -
Growth and form of two-dimensional rotating aggregates
(1993) [Artigo de periódico]We propose a two-dimensional particle-cluster aggregation model which considers explicitly linear and angular momentum conservation. Each aggregate is grown from a seed of given mass and given initial angular velocity, to ... -
Growth kinetics of solid-state-reacted fe-zr multilayer films
(1991) [Artigo de periódico]Multilayers of Fee0.33Zr0.67, prepared by electron beam evaporation, have been characterized by conversion electron Mijssbauer spectroscopy, Rutherford backscattering spectroscopy, and x-ray diffraction. Two phases, one ... -
Growth laws and self-similar growth regimes of coarsening two-dimensional foams : transition from dry to wet limits
(2012) [Artigo de periódico]We study the topology and geometry of two-dimensional coarsening foam with an arbitrary liquid fraction. To interpolate between the dry limit described by von Neumann’s law and the wet limit described by Marqusee’s equation, ... -
Growth of boron-doped few-layer graphene by molecular beam epitaxy
(2018) [Artigo de periódico]We investigated the growth of boron-doped few-layer graphene on a-Al2O3 (0001) substrates by molecular beam epitaxy using two different growth approaches: one where boron was provided during the entire graphene synthesis ... -
Growth of Paecilomyces variotii in B0 (diesel), B100 (biodiesel) and B7 (blend), degradation and molecular detection
(2015) [Artigo de periódico]A introdução de biodiesel ao diesel pode permitir que o combustível se torne mais suscetível ao crescimento de microorganismos, especialmente durante o armazenamento incorreto. Para analisar o efeito da adição de biodiesel ... -
Growth of TiO2 nanotube arrays with simultaneous Au nanoparticles impregnation: photocatalysts for hydrogen production
(2010) [Artigo de periódico]Um novo método para a fabricação de nanotubos (NTs) de TiO2 organizados e impregnados com nanopartículas (NPs) de ouro foi desenvolvido, e as propriedades estruturais, morfológicas e ópticas dos NTs obtidos foram investigadas. ... -
GSTM1, GSTT1, and GSTP1 polymorphisms, breast cancer risk factors and mammographic density in women submetted to breast cancer screening
(2012) [Artigo de periódico]Polimorfismos genéticos em genes relacionados com o metabolismo de xenobióticos, como os genes da superfamília das glutationa S-transferases (GSTM1, GSTT1 e GSTP1) têm sido associados com o aumento do risco para câncer de ... -
Guia de percurso urbano
(1989) [Artigo de periódico]