797 research outputs found
A PolÃtica Monetária Recente: Alguns Aspectos CrÃticos
Este Artigo tem como Objetivo Apresentar uma Análise das Práticas Atuais da PolÃtica Monetária, a PolÃtica de Regras Monetárias . Discute o Contexto Histórico em que Tais Práticas Apareceram, e suas Implicações, Especialmente de que a Oferta Monetária Passa a ser é Endógena, e não Exógena, como na Visão Monetarista Tradicional. a Nova Doutrina Também Faz a Suposição Extrema de que Embora a PolÃtica Monetária Possa ser Efetiva no Curto Prazo, Ela é Neutra no Longo Prazo. esta Hipótese Bem como suas Implicações para a PolÃtica Monetária Podem ser Sujeitas a Várias CrÃticas que Serão Desenvolvidas neste Trabalho.
Desregulamentação dos Mercados de Trabalho e Desemprego nas Economias Capitalistas Avançadas
AVALIAÇÃO EXPERIMENTAL E NUMÉRICA DA CINÉTICA DO CONGELAMENTO DO MÚSCULO DE ABRÓTEA (Urophycis brasiliensis)
This work carried out an experimental and numerical study of the kinetics of freezing of the Brazilian codling (Urophycis brasiliensis) muscle in air blast freezer, with air temperature set at 253.15 K and the average convective heat transfer coefficient at 25.4 W m-2 K-1. The initial temperature of the fish muscle was 277.15 K and the final temperature 255.15 K. The objective of this work was verify the best agreement between the experimental temperature profile and the numerical temperature profile to Brazilian codling muscle, using the CFD (Computational Fluid Dynamics) as numerical tool. In relation to the obtained results, it was verified that a good agreement between the experimental and numerical temperature profiles for the Brazilian codling muscle. The experimental freezing time found was 6618 s, and the freezing time through the numerical simulation was 6246 s. The error percentage found was 5.6%.Este trabalho realizou um estudo experimental e numérico da cinética de congelamento do músculo de abrótea (Urophycis brasiliensis) em uma câmara fria de convecção a ar forçado, com a temperatura do ar fixada em 253,15 K e o coeficiente convectivo médio de transferência de calor de 25,4 W m-2 K-1. A temperatura inicial do músculo do pescado foi de 277,15 K e a temperatura final de 255,15 K. O objetivo deste trabalho foi verificar a melhor concordância entre o perfil de temperatura experimental e o perfil de temperatura numérico para o músculo de abrótea, utilizando o CFD (Computational Fluid Dynamics) como ferramenta numérica. Em relação aos resultados obtidos, verificou-se uma boa concordância entre os perfis experimentais e numéricos de temperatura para o músculo de abrótea. O tempo de congelamento experimental encontrado foi de 6618 s, e o tempo de congelamento pela simulação numérica foi de 6246 s. O percentual de erro encontrado foi de 5,6%
Schwinger multichannel method: A study of a Feshbach resonance in e-H_2 collisions
We present results of the application of the Schwinger multichannel method to study the role of Feshbach resonances on the elastic and electronic excitation cross sections in e-H_2 collisions. Using a ^2Σ_g^+2 resonance associated with the a ^3Σ^+_g and E^1Σ^+_g states of H_2 as an example, we quantitatively illustrate the dramatic influence of open channels on the decay of such Feshbach resonances in electron-molecule collisions
Growth, oil and protein yield of Jatropha curcas L. populations
Jatropha curcas L. is an oilseed with multiple applications, especially the pharmaceutical-industrial one. Cultivation is still very low due to the lack of commercial varieties, therefore, with the need to start the genetic improvement program and select superior genotypes, it is essential to know the genetic variability of the culture. Thus, the purpose of this study was to evaluate the vegetative growth, grain yield and oil and protein content in seeds populations of Jatropha curcas, to support the species breeding program. The experiment was carried out at the University Federal de Viçosa, State of Minas Gerais, Brazil, using a randomized complete block split-plot design with four replications and 4-plant plots, spaced at 2.5 m. Each plot consisted of clones of six populations coming from the towns of Janaúba (J1, J2, J3, J4 and J5) and Bonfim (B1), located in Minas Gerais. The 4.5-year-old populations were evaluated for plant height, stem diameter, leaf and fruit dry matter, grain yield and oil and protein content. The populations presented different plant heights (2.97 m), stem diameters (13.49 cm) and leaf dry matter (0.818 g) amounts. The J5 population showed taller plants (3.29 m) with longer stem diameter (15.34 cm). The greatest dry leaf weight (0.864 g leaf-1) was observed in the J2 population. The populations did not present genetic variability for fruit dry matter, grain yield and oil and protein content. Overall, the J5 population stood out with the highest levels of growth, grain yield and seed oil (31.7%) content
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