Screening Effect On The Plasma Heating By Inverse Bremsstrahlung

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)The effect of Coulomb screening on the inverse-bremsstrahlung heating process in a plasma illuminated by a laser beam is discussed. It is shown that, although the screening effect actually lowers the electron-nuclei interaction, a situation may arise, namely, when the laser frequency approaches the plasma frequency, in which an enhancement of the collisional plasma heating can be expected. © 1979 The American Physical Society.19417961800CNR; São Paulo Research Foundation; 2011/23832-6; FAPESP; São Paulo Research Foundation; 2013/07600-3; FAPESP; São Paulo Research FoundationFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Effect Of A Radiation Field On Electrons Bound On Liquid Helium

Using the image-potential model, we discuss the influence of a radiation field on the distortion of the bound states of an electron trapped on a liquid-helium surface. It is shown that, for moderate field strengths, the ionization energy decreases with increasing field strength. © 1983 The American Physical Society.2895313531

Photoacoustic Assessment Of The In Vivo Genotypical Response Of Corn To Toxic Aluminium

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)[No abstract available]1153341343ACRL; Association of College and Research Libraries; CAPES; Association of College and Research LibrariesCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Ictiofauna Dos Enclaves De Floresta úmida Nos Planaltos Da Ibiapaba E Do Araripe, Nordeste Do Brasil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Humid highland forest enclaves are remnants of Atlantic Forest found in tablelands within the Caatinga biome (Northeastern Brazil), which emerged during interglacial periods in the Pleistocene. These ecosystems have a highly diverse and endemic fish fauna. Most earlier surveys have focused on the tableland of Borborema (Pernambuco and Paraíba States). In this study we surveyed the fish fauna of the humid forest enclaves in the tablelands of Ibiapaba and Araripe, based on samples collected in the rainy season (March and April) between 2009 and 2014. The 45 sampling points covered rivers, streams and reservoirs in five river basins belonging to three ecoregions. The species were listed according to drainage divide, and endemism was determined for each ecoregion and for the Caatinga. Our area was more species-rich (n=59) than Borborema (n=27). The samples included five introduced species and 29 species endemic to the Caatinga (49.1% of the sampled species). The distribution of Parotocinclus haroldoi was expanded to the Mid-Northeastern Caatinga ecoregion (Timonha river basin, Ceará State). Our study intends to make a significant contribution to current knowledge of the ichthyofauna in humid highland forest enclaves of semiarid Northeastern Brazil, identified as a priority in the conservation of the biodiversity in the Caatinga. © 2016, Universidade Estadual de Campinas UNICAMP. All rights reserved.164457463/2012-0, CNPq, Conselho Nacional de Desenvolvimento Científico e Tecnológico552009/2011-3, CNPq, Conselho Nacional de Desenvolvimento Científico e Tecnológico552086/2011-8, CNPq, Conselho Nacional de Desenvolvimento Científico e TecnológicoConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Optical Absorption Measurements In A New Composite Material By Combined Photoacoustic And Beam Transmission Techniques

The absorption coefficient of a highly absorbing (β>105 cm-1) new composite produced in our laboratory, namely manganese dioxide surface-impregnated polyethylene (MnO2-PE) film, has been measured in the visible range. We have employed a combination of concurrently taken photoacoustic and beam transmission data. This combination proved to be an effective means for the optical evaluation of highly absorptive samples which dispenses with the need for prior knowledge of the sample reflectivity. Theoretical interpretation of MnO2-PE absorption profile, with due account of the processes underlining the photoacoustic signal generation, reveals a semiconductor behavior with an estimated effective gap wavelength of 8050 Å. Technical implications of the availability of these highly absorptive flexible films are briefly considered.5794431443

Implicit Stochastic Optimization for deriving reservoir operating rules in semiarid Brazil

Este artigo investiga a aplicação de Otimização Estocástica Implícita (OEI) para determinar regras de operações mensais em um sistema de reservatórios localizado no nordeste semi-árido brasileiro. OEI emprega um modelo de otimização determinística para encontrar alocações ótimas do reservatório sob vários cenários possíveis de afluências e posteriormente constrói as regras a partir da análise deste conjunto de liberações ótimas. As políticas operacionais fornecem a alocação mensal do reservatório condicionada ao armazenamento no início do mês e a afluência prevista para o mês. Além da clássica análise de regressão, este estudo estabelece as regras por meio de uma estratégia de interpolação bidimensional. Após a sua identificação, as regras são aplicadas para operar o sistema sob novas realizações de afluências e mostram habilidade para produzir políticas semelhantes às obtidas a partir de otimização determinística tendo estas mesmas afluências como previsão perfeita.._________________________________________________________________________________________ ABSTRACT: This paper deals with the application of Implicit Stochastic Optimization (ISO) to determine monthly operating rules for a reservoir system located in the semiarid Northeast of Brazil. ISO employs a deterministic optimization model to find optimal reservoir allocations under several possible inflow scenarios and later constructs the rules by analyzing the ensemble of these optimal releases. The operating policies provide the monthly reservoir release conditioned on the storage at the beginning of the month and the inflow predicted for the month. In addition to the classical regression analysis, this study establishes the rules by a two-dimensional interpolation strategy. After the rules are identified, they are applied to operate the system under new inflow realizations and show ability to produce policies similar to those obtained by deterministic optimization taking the same inflows as perfect forecasts