1,066 research outputs found
Detailed Analysis of Nearby Bulgelike Dwarf Stars II. Lithium Abundances
Li abundances are derived for a sample of bulgelike stars with isochronal
ages of 10-11 Gyr. These stars have orbits with pericentric distances, Rp, as
small as 2-3 kpc and Zmax < 1 kpc. The sample comprises G and K dwarf stars in
the metallicity range -0.80<[Fe/H]< +0.40. Few data of Li abundances in old
turn-off stars (> 4.5 Gyr) within the present metallicity range are available.
M67 (4.7 Gyr) and NGC 188 (6 Gyr) are the oldest studied metal-rich open
clusters with late-type stars. Li abundances have also been studied for few
samples of old metal-rich field stars. In the present work a high dispersion in
Li abundances is found for bulgelike stars for all the metallicity range,
comparable with values in M67. The role of metallicity and age on a Li
depletion pattern is discussed. The possible connection between Li depletion
and oxygen abundance due to atmospheric opacity effects is investigated.Comment: 9 pages, 7 figure
Propriedades fĂsicas e infiltração de água de um Latossolo Vermelho Amarelo (Oxisol) do noroeste do estado de SĂŁo Paulo, Brasil, sob trĂŞs condições de uso e manejo
This study presents the results obtained in a field experiment carried out at Glicério, Northwest of São Paulo state, Brazil, whose objective was to analyze changes of selected soil physical properties and water infiltration rates on a Yellow-Red Latosol, under three different management conditions. The experimental design was arranged as completely randomized split-block with twelve treatments, which corresponded to four depths (0-0.05 m; 0.05-0.10 m; 0.10-0.20 m and 0.20-0.40 m) and three conditions of soil use and management with four replications. The soil surface conditions were: conventional tillage (one disking with moulboard plus two levelling passes with harrow), nine months before starting filed experiences; recent conventional tillage (also one disking with moulboard plus two levelling passes with harrow) and native forest. The conventional tillage areas were cropped for about fifteen years with annual cultures. The considered soil general physical properties were: macroporosity, microporosity, total porosity, bulk density, soil moisture and penetration resistance and, in addition; soil water infiltration rates were also recorded. According to our results, differences on general soil physical properties and infiltration rates appeared when both tilled sub-treatments and native forest were compared. Both, plots recently prepared by conventional tillage and those prepared by tillage but left nine months in rest, presented a statistically significant decrease of constant (final) water infiltration rates of 92.72% and 91.91% when compared with native forest plots
Seed predation and germination of Peltogyne gracilipes (Ducke) in three forest types on Maracá Island, Roraima, Brazil
Moscas-das-frutas e seus parasitĂłides associados a frutos individualizados de acerola (Malpighia glabra l.) no municĂpio de BelĂ©m, Pará.
An updated phylogenetic classification of Corynespora cassiicola isolates and a practical approach to their identification based on the nucleotide polymorphisms at the ga4 and caa5 loci.
Primeiro registro de Anastrepha Fraterculus (Diptera: Tephritidae) no Estado do Pará.
Resumo 1496-2
Principais espĂ©cies de mosca-das-frutas e seus inimigos naturais em frutos comercializados em feiras livres do municĂpio de BelĂ©m, Pará.
Resumo 1609-1
Primeiro registro de Anastrepha Fraterculus (Diptera: Tephritidae) no estado do Pará.
Resumo 1496-2
Identificação das principais espécies de mosca-das-frutas e seus inimigos naturais na ilha de Cotijuba, Pará.
Resumo 1596-1
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