973 resultados para 440


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实验制备了Dy^3+掺杂Ge-Ga—Se系统硫系玻璃样品,测试了玻璃的密度、显微硬度、可见-红外透射光谱、荧光光谱以及荧光寿命。根据玻璃的密度计算了玻璃的摩尔体积以及致密度。讨论了玻璃的这些性能随系统平均配位数的变化关系。实验结果表明:该系统中配位数大于2.67的玻璃在1.3μm具有较好的发光性能,荧光寿命在440-530μs之间,当玻璃组成位于化学门槛即平均配位数为2.73时玻璃的发光强度最强。

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We report on ultrabroad infrared (IR) luminescences covering the 1000-1700-nm wavelength region, from Bi-doped 75GeO(2) 20RO-5Al(2)O(3) 1B(2)O(3) (R = Sr, Ca, and Mg) glasses. The full width at half-maximum of the IR luminescences excited at 980 nm increases (315 -> 440 -> 510 nm) with the change of alkaline earth metal (Mg2+ -> Ca2+ -> Sr2+). The fluorescence lifetime of the glass samples is 1725, 157, and 264 mu s when R is Sr, Ca, and Mg, respectively. These materials may be promising candidates for broad-band fiber amplifiers and tunable laser resources.

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Absorption and emission spectral properties of GdVO4 single crystal doped with Ho3+ ions were investigated at room temperature. Polarized absorption cross section is calculated in the range of 400-2200nm. Results were analyzed and parameters were calculated based on Judd-Ofelt theory, the emission spectrum shows that the emission intensity around the wavelength of 546 nm associated with transition S-5(2) -> I-5(8) is much stronger than other bands in the observed range and potentially enable the green light output around this emission band in this crystal. (c) 2006 Elsevier B.V. All rights reserved.

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We examined the incidental catches of American shad (Alosa sapidissima) taken during research cruises and in commercial and recreational landings along the Pacific coast of North America during over 30 years of sampling. Shad, an introduced species, was mainly found over the shallow continental shelf, and largest catches and highest frequency of occurrences were found north of central Oregon, along the coasts of Washington and Vancouver Island, and in California around San Francisco Bay. Migrations to the north off Washington and Vancouver were seen during spring to fall, but we found no evidence for large-scale seasonal migrations to the south during the fall or winter. The average weight of shad increased in deeper water. Sizes were also larger in early years of the study. Most were caught over a wide range of sea surface temperatures (11–17°C) and bottom temperatures (6.4–8.0°C). Abundance of shad on the continental shelf north of 44°N was highly correlated with counts of shad at Bonneville Dam on the Columbia River in the same year. Counts were negatively related to average weights and also negatively correlated with the survival of hatchery coho salmon (Oncorhynchus kisutch), indicating that survival of shad is favored by warm ocean conditions. Examining the catch during research cruises and commercial and recreational landings, we concluded that American shad along the Pacific coast have adapted to the prevailing environmental conditions and undertake only moderate seasonal migrations compared with the long seasonal migrations of shad along the Atlantic coast of North America. We suggest that the large spawning populations in the Columbia River and San Francisco Bay areas explain most of the distributional features along the Pacific coast.

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Long-term time series of zooplankton data provide invaluable information about the fluctuations of species abundance and the stability of marine community structure. These data have demonstrated that environmental variability have a profound effect on zooplankton communities across the Atlantic basin (Beaugrand et al., 2002; Frank et al., 2005; Pershing et al., 2005). The value of these time series increases as they lengthen, but so does the likelihood of changes in sampling or processing methods. Sam-pling zooplankton with nylon nets is highly selective and biased because of mesh selectivity, net avoidance, and damage to fragile organisms. One sampling parameter that must be standardized and closely monitored is the speed of the net through the water column. Tow speed should be as fast as possible to minimize net avoid-ance by the organisms, but not so fast as to damage soft bodied zooplankters or extrude them through the mesh (Tranter et al., 1968; Anderson and Warren, 1991).

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O presente trabalho visa caracterizar os acidentes com envolvimento de motocicletas no perímetro urbano de Paranavaí-PR, em 2007, e estimar o impacto econômico das internações advindas destes, na perspectiva do Sistema Único de Saúde (SUS) e para o Seguro obrigatório que cobre danos pessoais causados por veículos automotores de via terrestre (DPVAT). Trata-se de um estudo transversal, retrospectivo, que se baseia em buscas e análises das bases de dados do Serviço integrado de atendimento ao trauma e emergência (SIATE), do DPVAT e do Sistema de informações sobre internações do SUS (SIH-SUS), com vias a análise das variáveis: gênero, idade, tipo de acidente, condição da vítima no acidente, mês da ocorrência, gravidade, frequência de internação hospitalar, custo, componentes de custo, óbitos e tempo médio de permanência no SUS. A busca ocorreu, primeiramente, no sistema do SIATE para conhecer todos os acidentados com envolvimento de motocicletas no perímetro urbano de Paranavaí, no ano de 2007. De posse desses nomes, as buscas seguintes ocorreram no sistema interno do DPVAT e no SIH-SUS. O profissional do SIATE, no momento da abordagem da ocorrência julga a gravidade da vítima conforme códigos, sendo 1 para ferimentos leves, 2 para graves sem risco à vida, 3, graves com risco à vida e 4, os óbitos. A população estudada constou de 655 vítimas (440 homens e 215 mulheres), com média de idade de 29,5 anos, sendo que 598 (91,3%) saíram lesionadas e 11 (1,7%) vieram a óbito. O condutor de motocicleta foi o mais acometido e o tipo de acidente mais comum aconteceu entre um automóvel e uma motocicleta. Com relação à frequência da internação hospitalar (pelo SUS, DPVAT ou ambos), foi, em média, de 27% (177 de 655). Do total de vítimas internadas verificou-se que 106 tiveram cobertura do DPVAT, 58 do SUS e 13 de ambos. As internações pelo DPVAT geraram um custo total de R$ 191.423,43, custo médio de R$ 1.608,60 por internação. Com relação aos custos das internações do SUS, os referidos acidentes geraram o pagamento de R$ 42.342,20, perfazendo a média de R$ 450,44 por AIH e de R$ 596,37 por paciente. O custo médio da internação dos acidentes de trânsito com envolvimento de motocicletas foi de R$ 1.321,00, sendo que para o código 1 foi de R$ 885,00, para o código 2 de R$ 1.377,00 e para o código 3 de R$ 2.034,00. Portanto, foi possível caracterizar os acidentes e chegar a estimativas de quanto se gasta com as internações advindas destes, além disso, este é um indicativo claro da necessidade de adotar políticas públicas que priorizem a aplicação dos recursos financeiros e humanos na redução dos acidentes e da sua gravidade.

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Through most of their annual migration, gray whales, Eschrichtius robustus, remain within 10 km of shore, but in the Southern California Bight many individuals migrate much farther from shore. This paper summarizes aerial survey and photogrammetric efforts to determine body lengths and temporal and spatial distributions of migratory gray whales in the southern portion of the Southern California Bight. Aerial surveys were flown along 13 east–west transects between lat. 32°35′N and 33°30′N during the southbound gray whale migratory seasons of 1988–90 in the Southern California Bight. Photogrammetry was used to obtain body length estimates of animals during some of the surveys. A total of 1,878 whales in 675 groups were sighted along 25,440 km of transect distance flown and 217 body lengths were measured. Using position and heading data, three major migratory pathways or corridors in the southern portion of the bight are defined. Those migrating offshore were split almost evenly between two corridors along the west sides of Santa Catalina and San Clemente Islands. These corridors converge on the mainland coast between San Diego and the United States–Mexico border. No whales larger than 11.5 m were photographed within 30 km of the mainland coast, suggesting that smaller, and presumably younger, whales use the coastal migratory corridor through the California Bight.

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Annual abundance estimates of belugas, Delphinapterus leucas, in Cook Inlet were calculated from counts made by aerial observers and aerial video recordings. Whale group-size estimates were corrected for subsurface whales (availability bias) and whales that were at the surface but were missed (detection bias). Logistic regression was used to estimate the probability that entire groups were missed during the systematic surveys, and the results were used to calculate a correction to account for the whales in these missed groups (1.015, CV = 0.03 in 1994–98; 1.021, CV = 0.01 in 1999– 2000). Calculated abundances were 653 (CV = 0.43) in 1994, 491 (CV = 0.44) in 1995, 594 (CV = 0.28) in 1996, 440 (CV = 0.14) in 1997, 347 (CV = 0.29) in 1998, 367 (CV = 0.14) in 1999, and 435 (CV = 0.23, 95% CI=279–679) in 2000. For management purposes the current Nbest = 435 and Nmin = 360. These estimates replace preliminary estimates of 749 for 1994 and 357 for 1999. Monte Carlo simulations indicate a 47% probability that from June 1994 to June 1998 abundance of the Cook Inlet stock of belugas was depleted by 50%. The decline appears to have stopped in 1998.

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Operational modifications based on recreational angler activity patterns can be successfully formulated to increase creel survey efficiency without a significant loss of information. This study was conducted to estimate the amount of Texas marine sport-boat angler interview and retained fish data (bay and Gulf) that would be missed both coastwide and within each bay system if surveys were terminated early when no angler interviews were conducted by a specified time. Using this method, <3 percent of the total interviews and retained fish would be missed coastwide by terminating surveys at 1400 hours on weekends and 1600 hours on weekdays throughout the survey year. This would result in the early termination of 14 percent of the weekend surveys and 23 percent of the weekday surveys, thus allowing an annual redirection of 440 work-hours and $6,063 in operating expenses.