9,034 research outputs found
Processo de Seleção Escape para Obtenção de Plantas de Pessegueiro e Ameixeira com Alta Sanidade.
bitstream/item/30951/1/Circular-84.pd
Dynamics of a Generalized Cosmological Scalar-Tensor Theory
A generalized scalar-tensor theory is investigated whose cosmological term
depends on both a scalar field and its time derivative. A correspondence with
solutions of five-dimensional Space-Time-Matter theory is noted. Analytic
solutions are found for the scale factor, scalar field and cosmological term.
Models with free parameters of order unity are consistent with recent
observational data and could be relevant to both the dark-matter and
cosmological-"constant" problems.Comment: 13 page
Radiolysis of ammonia-containing ices by energetic, heavy and highly charged ions inside dense astrophysical environments
Deeply inside dense molecular clouds and protostellar disks, the interstellar
ices are protected from stellar energetic UV photons. However, X-rays and
energetic cosmic rays can penetrate inside these regions triggering chemical
reactions, molecular dissociation and evaporation processes. We present
experimental studies on the interaction of heavy, highly charged and energetic
ions (46 MeV Ni^13+) with ammonia-containing ices in an attempt to simulate the
physical chemistry induced by heavy ion cosmic rays inside dense astrophysical
environments. The measurements were performed inside a high vacuum chamber
coupled to the heavy ion accelerator GANIL (Grand Accelerateur National d'Ions
Lourds) in Caen, France.\textit{In-situ} analysis is performed by a Fourier
transform infrared spectrometer (FTIR) at different fluences. The averaged
values for the dissociation cross section of water, ammonia and carbon monoxide
due to heavy cosmic ray ion analogs are ~2x10^{-13}, 1.4x10^{-13} and
1.9x10^{-13} cm, respectively. In the presence of a typical heavy cosmic
ray field, the estimated half life for the studied species is 2-3x10^6 years.
The ice compaction (micropore collapse) due to heavy cosmic rays seems to be at
least 3 orders of magnitude higher than the one promoted by (0.8 MeV) protons .
In the case of the irradiated H2O:NH3:CO ice, the infrared spectrum at room
temperature reveals five bands that were tentatively assigned to vibration
modes of the zwitterionic glycine (+NH3CH2COO-).Comment: Accepted to be published in Astronomy and Astrophysics; Number of
pages: 12; Number of Figures: 7; Number of Tables:
Anisotropic elastic theory of preloaded granular media
A macroscopic elastic description of stresses in static, preloaded granular
media is derived systematically from the microscopic elasticity of individual
inter-grain contacts. The assumed preloaded state and friction at contacts
ensure that the network of inter-grain contacts is not altered by small
perturbations. The texture of this network, set by the preparation of the
system, is encoded in second and fourth order fabric tensors. A small
perturbation generates both normal and tangential inter-grain forces, the
latter causing grains to reorient. This reorientation response and the
incremental stress are expressed in terms of the macroscopic strain.Comment: 7 pages, 2 figures. Accepted version. [email protected]
[email protected]
A gestão do conhecimento como ferrammenta para potencializar o desenvolvimento de equipes na geração e execução de projetos de P&D.
Breve apreciação da gestão do conhecimento na Embrapa; Um modelo de maturidade da gestão do conhecimento como ferramenta de análise de uma instituição; Suporte e referencial teórico para implantação de um programa de GC; Ambiente de conhecimento; Inteligência competitiva; Redes de relacionamento; Apoio à pesquisa; Uma perspectiva de gestão do conhecimento para unidades de pesquisa; Aspectos gerais de um programa para unidades de pesquisa; Aspectos gerais de um programa para gestão do conhecimento aplicada a projetos de PD&I; Ações e efeitosda gestão do conhecimento no âmbito de um projeto de P&D.bitstream/item/58221/1/doc118.pd
Fosfatos Naturais na Adubação de Sistema de Culturas de Verão com Ênfase no Arroz Irrigado.
bitstream/item/30829/1/Circular-66.pd
Experiência a campo com inseminação artificial de suínos.
bitstream/item/59338/1/CUsersPiazzonDocuments16.pd
Uso de modelos de simulação sócio-bio-econômico integrado como ferramenta para o desenvolvimento agrário na região sudoeste do Rio Grande Sul.
Suporte tecnológico tem sido oferecido aos produtores com a finalidade de aumentar a eficiência produtiva e fornecer subsídios para as suas tomadas de decisões; entretanto, os métodos tradicionais de pesquisa e extensão estão sendo cada vez mais questionados, principalmente quanto ao custo e tempo necessário para oferecer soluções aos problemas enfrentados pelos produtores.bitstream/item/109814/1/USO-DE-MODELOS-DE-SIMULACAO.pd
Cuidados com a leitoa de reposição.
bitstream/item/59499/1/CUsersPiazzonDocuments14.pdfAcesso em: 13 jun. 2007
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