12,112 research outputs found
Thermal treatment of superconductor thin film of the BSCCO system using domestic microwave oven
In this work, we report the preparation of a superconductor thin film of the
BSCCO system using a good quality powder with nominal composition
Bi_{1.8}Pb_{0.4}Sr_2CaCu_2O_x which was thermally treated using a domestic
microwave oven (2.45 GHz, 800 W). This film was grew on a single crystal of
LaAlO_3(100) substrate and exhibited a crystalline structure with the c-axis
perpendicular to the plane of the substrate. An onset superconducting
transition temperature was measured at 80 K.Comment: 4 pages, 5 figure
Anotação de genes relacionados à tolerância a seca em arroz (Oryza sativa) de terras altas.
O objetivo deste trabalho foi identificar e anotar os genes expressos em resposta ao déficit hídrico em tecido foliar de duas cultivares brasileiras de arroz de terras altas, a cultivar tolerante à seca Douradão e a cultivar sensível Primavera.Apresentação oral - Pós-graduação
Zinc abundances in Galactic bulge field red giants: implications for DLA systems
Zinc in stars is an important reference element because it is a proxy to Fe
in studies of damped Lyman-alpha systems, permitting a comparison of chemical
evolution histories of bulge stellar populations and DLAs. In terms of
nucleosynthesis, it behaves as an alpha element because it is enhanced in
metal-poor stars. The aim of this work is to derive the iron-peak element Zn
abundances in 56 bulge giants from high resolution spectra. These results are
compared with data from other bulge samples, as well as from disk and halo
stars, and damped Lyman-alpha systems, in order to better understand the
chemical evolution in these environments. High-resolution spectra were obtained
using FLAMES+UVES on the Very Large Telescope. We find [Zn/Fe]=+0.24+-0.02 in
the range -1.3 < [Fe/H] < -0.5 and [Zn/Fe]=+0.06+-0.02 in the range -0.5 <
[Fe/H] -0.1, it shows a spread of -0.60 < [Zn/Fe]
< +0.15, with most of these stars having low [Zn/Fe]<0.0. These low zinc
abundances at the high metallicity end of the bulge define a decreasing trend
in [Zn/Fe] with increasing metallicities. A comparison with Zn abundances in
DLA systems is presented, where a dust-depletion correction was applied for
both Zn and Fe. Finally, we present a chemical evolution model of Zn enrichment
in massive spheroids, representing a typical classical bulge.Comment: Accepted in Astronomy & Astrophysics, in press Date of acceptance:
13/05/2015. 19 pages, 14 Figs in Astronomy & Astrophysics, 201
Dinâmica da liberação de nutrientes de compostos orgânicos e exigências nutricionais do abacaxizeiro BRS Imperial.
As adubações para diferentes culturas trabalhadas na Embrapa Mandioca e Fruticultura são recomendadas em função das fontes de corretivos de solo e dos fertilizantes convencionais. Com exceção da cultura da banana, inexistem recomendações consolidadas com critérios científicos para fertilização orgânica ou orgânica enriquecida com fontes não convencionais. Nesse sentido, a compreensão do comportamento dos materiais genéticos frente a esse sistema de produção torna-se importante
Environmental Variations Drive Polyploid Evolution In Neotropical Eugenia Species (myrtaceae)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Polyploidy is one of the most important mechanisms of speciation and diversification in plant evolution. Polyploidy results in genetic variation among individuals of the same species and even between populations, and may be responsible for differences in environmental tolerance between populations of the same species. This study determined chromosome numbers of Eugenia L. (Myrtaceae, x = 11) for 26 populations of 14 species by conventional cytogenetic techniques. Nine species (13 populations) were diploid (2n = 2x = 22), but diploid and/or polyploid cytotypes were found in the other five species (13 populations), with 2n = 33, 2n = 44, and 2n = 55. Data on chromosome number/ploidy level for other Eugenia species/populations analysis. For each collection point (32 species and 62 populations), environmental variables were recorded using georeferencing techniques through the DIVA-GIS v.7.5 program. Environmental variables such as temperature, altitude, rainfall, solar radiation, soil type, and vegetation were analyzed with the R program, using Mann-Whitney and chi-square tests, principal component analysis, and graphic analyses, such as scatterplots, boxplots, and barplot. Polyploid and diploid populations had different spatial distribution patterns and were found in areas subjected to different environmental conditions. Polyploid individuals were collected from locations with more adverse environmental conditions, usually at higher elevations than the diploid individuals. Polyploidy allows species to occur at locations with varying environmental conditions. As diploidy and polyploidy occur under different environmental conditions, species with cytotypes exhibit wide environmental tolerance.154CAPESCNPq - Conselho Nacional de Desenvolvimento Cientifico e tecnologicoFUNCAP - Fundacao Cearense de Apoio ao Desenvolvimento Cientifico e Tecnologico [10582430-5]CNPq [479263/2011-6, 471065/2004-8]FAPESP - Fundacao de Amparo a Pesquisa do Estado de Sao Paulo [04/13041-8, 01/13169-6]Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP
Estudo dos solos do município de Herval.
bitstream/item/41396/1/Herval.pdf; bitstream/item/41397/1/mapa-geomorfologia.pdf; bitstream/item/41398/1/mapa-solos.pdf; bitstream/item/41399/1/mapa-uso-das-terras.pd
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