997 resultados para 7140-215


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采用溶胶-凝胶方法制备的(CH2)2Si(OC2H5)2预聚体涂膜液中,掺入碱催化的SiO2悬胶体涂膜液,采用旋涂法在掺钕磷酸盐激光玻璃棒端面涂制了改性的防潮膜。当涂膜液中(CH2)2Si(OC2H5)2和SiO2物质的量之比为1:1时。热处理后的膜层耐摩擦性能明显改善;表面粗糙度的均方根值为1.245nm;膜层激光破坏阈值大于15J/cm^2(1053nm,1ns);在80℃和95%RH的封闭环境中静置336h,膜层的透过率、接触角基本不变。结果证明膜层具有稳定的疏水结构和很好的防潮性能,膜层强度增加,

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Radio and sonic telemetry were used to investigate the tidal orientation, rate of movement (ROM), and surfacing behavior of nine Kemp's ridley turtles, Lepidochelys kempii, tracked east of the Cedar Keys, Florida. The mean of mean turtle bearings on incoming (48 ± 49 0) and falling (232 ± 41 0) tides was significantly oriented to the mean directions of tidal flow (37±9°, P<0.0025, and 234±9 0, P<0.005, respectively). Turtles had a mean ROM of 0.44±0.33 km/h (range: 0.004-1.758 km/h), a mean surface duration of 18± 15 s (range: 1-88 s), and a mean submergence duration of 8.4± 6.4 min (range: 0.2-60.0 min). ROM was negatively correlated with surface and submergence durations and positively correlated with the number of surfacings. Furthermore, ROMs were higher and surface and submergence durations were shorter during the day. Daily activities of turtles were attributed to food acquisition and bioenergetics.

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采用溶胶-凝胶方法制备(CH3)2Si(OC2H5)2预聚体涂膜液以及掺入SiO2悬胶体涂膜液改性,采用旋转法在掺钕磷酸盐激光玻璃棒端面涂制防潮膜,热处理后膜层固化。SiO2改性的CH3O防潮膜,热处理后的膜层耐摩擦性能明显改善。然后旋转涂制第二层多空性SiO2减反膜,涂膜胶体通过硅酸乙脂碱催化水解缩聚制得,减反膜的折射率为约1.25,玻璃棒涂膜后激光波长1053nm减少表面反射率6.5%-7.5%,双层膜激光破坏阈值12J/cm^2,1053nm/1ns,膜层表面粗糙度(RMS)2.523nm。直径20

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Estimation of the far-field centre is carried out in beam auto-alignment. In this paper, the features of the far-field of a square beam are presented. Based on these features, a phase-only matched filter is designed, and the algorithm of centre estimation is developed. Using the simulated images with different kinds of noise and the 40 test images that are taken in sequence, the accuracy of this algorithm is estimated. Results show that the error is no more than one pixel for simulated noise images with a 99% probability, and the stability is restricted within one pixel for test images. Using the improved algorithm, the consumed time is reduced to 0.049 s.

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Partially end-pumped slab laser is an innovative solid state laser, namely InnoSlab. Combining the hybrid resonator with partially end-pumping, the output power can be scaled with high beam quality. In this paper, the output intensity distributions are simulated by coordinate transformation fast Fourier transform (FFT) algorithm, comparing the thermal lens influence. As the simulated curves showed, the output mode is still good when the thermal lens effect is strong, indicating the good thermal stability of InnoSlab laser. Such a new kind of laser can be designed and optimized on the base of this simulation.

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Esta tese tem por objetivo analisar neologismos no contexto da política nacional coletados na imprensa, no início do século XXI. Busca-se compreender como estão se refletindo as mudanças sociais e políticas em nossa língua e em que medida a língua reflete essas mudanças. O dispositivo teórico são os princípios contidos na Análise do Discurso, com suporte, essencialmente, em estudiosos como Patrick Charaudeau, Dominique Maingueneau e Michel Pêcheux, e nos conceitos articulados no campo da Linguística Cognitiva no que diz respeito à mobilização das relações de sentidos. Investiga-se a presença ou não de traços de pejoratividade e ironia nesses novos termos, bem como os aspectos intertextuais e interdiscursivos envolvidos nesse jogo de criação verbal, o que conduz às noções de palavra-chave, palavra-testemunha, palavra-escudo e palavra-espada, levando-se em conta que os termos representam e incorporam as marcas da sociedade e dos processos políticos vivenciados. Traz-se, ao final, uma análise do corpus coletado, um total de 215 verbetes

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