Navegação Ciências Exatas e da Terra por Título
Resultados 3984-4003 de 6541
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Numerical model of electromagnetic stirring for continuos casting billets
(2002) [Artigo de periódico]Thispaperintroducesanumericalmodelofanelectromagnetic rotary stirrer based on the finite-element model.Such stirrers are used to improve the quality of continuously cast steel, particularly billets and blooms. The method ... -
Numerical renormalization-group study of the correlation functions of the antiferromagnetic spin 1/2 Heisenberg chain
(1995) [Artigo de periódico]We use the density-matrix renormalization-group technique developed by White to calculate the spin correlation functions (S2n+I S2n)=(-1) 1 w(l,N) for isotropic Heisenberg rings up to N=70 sites. The correlation functions ... -
Numerical simulation of a negative ion plasma expansion into vacuum
(1997) [Artigo de periódico]The expansion into vacuum of a one-dimensional, collisionless, negative ion plasma is investigated in the framework of the Vlasov–Poisson model. The basic equations are written in a ‘‘new time space’’ by use of a rescaling ... -
Numerical simulation of bidimensional incompressible flows between moving surfaces
(2001) [Artigo de periódico]The goal of the present work is the numerical simulation of flows betwen moving surfaces. The method is based on the finite differences explicit Runge-Kutta multi-stage scheme with central spatial discretization and for ... -
Numerical simulations with the Galerkin least squares finite element method for the Burgers' equation on the real line
(2017) [Artigo de periódico]In this work we present an efficient Galerkin least squares finite element scheme to simulate the Burgers’ equation on the whole real line and subjected to initial conditions with compact support. The numerical simulations ... -
A numerical validation between the neutron transport and diffusion theories for a spatial kinetics problem
(2024) [Artigo de periódico]In this paper, a comparative analysis of numerical results of the neutron transport and diffusion theories for steady-state and transient multigroup problems is presented. The neutron transport equation is known as the one ... -
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Nutrient release, plant nutrition, and potassium leaching from polymer-coated fertilizer
(2017) [Artigo de periódico]The increase in food consumption and limitations in food production areas requires improved fertilizer efficiency. Slow- or controlled-release fertilizers are an alternative for synchronizing nutrient availability with the ... -
Nutritional composition of Eragrostis teff and its association with the observed antimutagenic effects
(2019) [Artigo de periódico]Eragrostis teff is an Ethiopian native grass plant ( Poaceae or Gramineae family) whose importance as a crop grain has increased in recent years. The aim of this study is to analyze the nutritional composition of its seeds ... -
Nutrition, mental health and violence : from pregnancy to postpartum cohort of women attending primary care units in southern Brazil - ECCAGE study
(2010) [Artigo de periódico]Background: Woman’s nutritional status, before and during pregnancy, is a strong determinant of health outcomes in the mother and newborn. Gestational weight gain and postpartum weight retention increases risk of overweight ... -
Os objetos de aprendizagem e o desenvolvimento das habilidades espaciais
(2013) [Artigo de periódico]Este artigo aborda o desenvolvimento das habilidades espaciais, como rotação mental, percepção espacial e visualização espacial, com a utilização de objetos digitais de aprendizagem, em alunos do Ensino Fundamental. Para ... -
Oblique Alfvén waves in a stellar wind environment with dust particles charged by inelastic collisions and by photoionization
(2022) [Artigo de periódico]The characteristics of Alfvén waves propagating in a direction oblique to the ambient magnetic field in a stellar wind environment are discussed. A kinetic formulation for a magnetized dusty plasma is adopted considering ... -
Obliquely propagating electromagnetic waves in magnetized kappa plasmas
(2016) [Artigo de periódico]Velocity distribution functions (VDFs) that exhibit a power-law dependence on the high-energy tail have been the subject of intense research by the plasma physics community. Such functions, known as kappa or superthermal ... -
A obra de Boltzmann em física
(2006) [Artigo de periódico]O objetivo do presente trabalho é proporcionar uma visão geral sobre a obra de Boltzmann em Física. Algumas de suas contribuições mais importantes são discutidas e contextualizadas. -
Observational constraints on the stellar recycled gas in active galactic nuclei feeding
(2024) [Artigo de periódico]Near-infrared long-slit spectroscopy has been used to study the stellar population (SP) of the low luminosity active galactic nuclei (AGNs) and matched analogues (LLAMA) sample. To perform the SP fits we have employed the ... -
Observational limits on companions to g29-38
(1994) [Artigo de periódico]Recent interest in the variable (DAV) white dwarf G29-38 has been stirred by a tentative report of a radial velocity variation that may be due to an unseen companion. Earlier evidence for a brown dwarf in the system has ... -
Observation of abnormal suppression of f0(980) production in p–Pb collisions at √s𝐍𝐍 = 5.02 TeV
(2024) [Artigo de periódico]The dependence of f0(980) production on the final-state charged-particle multiplicity in p–Pb collisions at √𝑠NN = 5.02 TeV is reported. The production of f0(980) is measured with the ALICE detector via the f0(980) → ... -
Observation of a multiplicity dependence in the pT-differential charm baryon-to-meson ratios in proton–proton collisions at √s = 13 TeV
(2022) [Artigo de periódico]The production of prompt D0, D+ s , and + c hadrons, and their ratios, D+ s /D0 and + c /D0, are measured in proton–proton collisions at √s = 13 TeV at midrapidity (|y| < 0.5) with the ALICE detector at the LHC. The ... -
Observation of a new excited beauty strange baryon decaying to Ξ−bπ+π−
(2021) [Artigo de periódico]The Ξ−bπ+π− invariant mass spectrum is investigated with an event sample of proton-proton collisions at √s=13 TeV, collected by the CMS experiment at the LHC in 2016–2018 and corresponding to an integrated luminosity of ... -
Observation of B0 s mesons and measurement of the B0 s /B+ yield ratio in PbPb collisions at √snn = 5.02 TeV
(2022) [Artigo de periódico]The B0 s and B+ production yields are measured in PbPb collisions at a center-of-mass energy per nucleon pair of 5.02 TeV. The data sample, collected with the CMS detector at the LHC, corresponds to an integrated luminosity ...
