901 research outputs found
Influência da técnica e da origem do propágulo na enxertia de campo em erva-mate (Ilex paraguariensis Saint Hilaire).
Como subsídio para o aprimoramento da qualidade da madeira de Pinus elliottii Engelm var. elliottii, plantado no sul do Brasil, foram estudados os efeitos de diferentes intensidades de desbaste em algumas de suas principais propriedades. Em função do aumento da intensidade de desbaste, observaram- se tendências de aumento da densidade básica, teor de lenho tardio, espessura dos anéis de crescimento, ângulo de inclinação das fibras e diâmetros externo einterno (lúmen) dos traqueóides. O comprimento dos traqueóides e os coeficientes de retratibilidade revelaram tendências inversas. Os teores de pentosana, lignina e celulose não foram significativamente influenciados pelo desbaste. A resistência à flexão estática apresentou seus maiores valores na madeira produzida nas parcelas submetidas a desbaste moderado, nas quais 25% da área basal foi removida
Turbulence generation by a shock wave interacting with a random density inhomogeneity field
When a planar shock wave interacts with a random pattern of pre-shock density
non-uniformities, it generates an anisotropic turbulent velocity/vorticity
field. This turbulence plays an important role at the early stages of the
mixing process in the compressed fluid. This situation emerges naturally in
shock interaction with weakly inhomogeneous deuterium-wicked foam targets in
Inertial Confinement Fusion (ICF) and with density clumps/clouds in
astrophysics. We present an exact small-amplitude linear theory describing such
interaction. It is based on the exact theory of time and space evolution of the
perturbed quantities behind a corrugated shock front for a single-mode
pre-shock non-uniformity. Appropriate mode averaging in 2D results in closed
analytical expressions for the turbulent kinetic energy, degree of anisotropy
of velocity and vorticity fields in the shocked fluid, shock amplification of
the density non-uniformity, and sonic energy flux radiated downstream. These
explicit formulas are further simplified in the important asymptotic limits of
weak/strong shocks and highly compressible fluids. A comparison with the
related problem of a shock interacting with a pre-shock isotropic vorticity
field is also presented.Comment: This article corresponds to a presentation given at the Second
International Conference and Advanced School "Turbulent Mixing and Beyond,"
held on 27 July - 07 August 2009 at the Abdus Salam International Centre for
Theoretical Physics, Trieste, Italy. That Conference Proceeding will be
published as a Topical Issue of the Physica Scripta IOP scienc
Fatty Acid Profile of Subcutaneous Fat in Lambs Finished on Either Olive Oil Cake‐Based Rations on Mediterranean‐Like Pastures in Chile
Use of galvanostatic coulometry in the analysis of arbidol drug
Arbidol is proved to easily and completely react with electrogenerated bromine in the ratio 2: 9; so procedures for the arbidol quantification in the neat substance and drugs are developed, the RSD value does not exceed 2%. A procedure for the coulometric determination of water in the arbidol substance using the Fisher method is proposed. © 2012 Pleiades Publishing, Ltd
Adaptabilidade e estabilidade de cultivares de milho no nordeste brasileiro no biênio 2006/2007.
Influência do tipo de aleitamento materno e da presença de anemia na mãe na concentração de hemoglobina aos 6 meses de idade
Adaptabilidade e estabilidade de cultivares de milho na zona agreste do nordeste brasileiro no biênio 2006/2007.
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