55 resultados para Concilio de Constanza (1414-1418)
em Chinese Academy of Sciences Institutional Repositories Grid Portal
Resumo:
道路建设在促进社会经济发展、方便人们生活的同时,也带来了环境污染、动植物栖息地破碎等严重的生态学后果,道路生态学随之成为生态学研究的重要前沿领域之一。20世纪90年代,道路生态学的研究重点转移到道路的生态学影响域等相关领域,包括生态学影响范围、类型及其形态、格局等。大量研究表明,道路对周边动植物等生物因子以及周围环境中土壤、水分和空气成分等生态因子的影响范围各不相同,道路生态学影响域的范围随着道路的利用率以及各生态因子种类及其变化特点而有所不同。在综述国内外学者对道路生态学影响域范围研究结果的基础上,建议中国应开展道路生态学影响域的综合研究,并将研究成果应用于道路规划的实践中,推动国内道路生态学研究的发展。参58
Resumo:
The effect of PMR-polyimide(POI) as the interfacial agent on the interface characteristics, morphology features and crystallization of poly (ether sulfone) /poly (phenylene sulfide) (PES/PPS) and poly(ether ether ketone)/poly (ether sulfone) (PEEK/PES) partly miscible blends were investigated by means of the scanning electron microscopy, WAXD and XPS surface analysis. It is found that the interfacial adhesion was enhanced remarkably, the size of the dispersed phase particles was reduced significantly and the miscibility was improved by the addition of POI. During melt blending cross-link and/or grafting reaction of POI with PES, PEEK and PPS homopolymers was detected, however the reaction activity of POI with PPS was much higher than that of PES and PEEK. It was also found that POI was an effective nucleation agent of the crystallization of PPS.
Resumo:
研究了以 5 -降冰片烯 -2 ,3-二羧酸单甲酯为端基的 PMR型聚酰亚胺 ( POI)作为界面介质对部分相容的聚醚砜 /聚苯硫醚 ( PES/ PPS)、聚醚醚酮 /聚醚砜 ( PEEK/ PES)共混体系的界面性质、形态结构及结晶行为的影响 .结果表明 ,POI可以有效地增强两相间的界面粘结 ,显著降低 PPS/ PES共混物中 PPS分散区的尺寸 ,改善两组分间的相容性 .在熔融共混过程中 ,POI从本体向界面扩散并同 PPS,PES产生交联和 /或接枝 ,POI同 PPS的反应活性远高于 PES,但 POI与 PES发生反应 . POI是 PPS结晶的有效成核剂
Resumo:
介绍了磁驱动滑动弧放电大气压非平衡等离子体产生技术的一些基本特性,着重叙叙述了磁驱动滑动滑动弧放电大气压平衡等离子体的产生装置(GDM)、基本原理、主要特性及应用中的一些问题。
Resumo:
Modeling study is performed to reveal the special features of the entrainment of ambient air into subsonic laminar and turbulent argon plasma jets. Two different types of jet flows are considered, i.e., the argon plasma jet is impinging normally upon a flat substrate located in atmospheric air surroundings or is freely issuing into the ambient air. It is found that the existence of the substrate not only changes the plasma temperature, velocity and species concentration distributions in the near-substrate region, but also significantly enhances the mass flow rate of the ambient air entrained into the jet due to the additional contribution to the gas entrainment of the wall jet formed along the substrate surface. The fraction of the additional entrainment of the wall jet in the total entrained-air flow rate is especially high for the laminar impinging plasma jet and for the case with shorter substrate standoff distances. Similarly to the case of cold-gas free jets, the maximum mass flow-rate of ambient gas entrained into the turbulent impinging or free plasma jet is approximately directly proportional to the mass flow rate at the jet inlet. The maximum mass flow-rate of ambient gas entrained into the laminar impinging plasma jet slightly increases with increasing jet-inlet velocity but decreases with increasing jet-inlet temperature.
Resumo:
本文分析了文献[1]对阻尼振子所提出的直接的量子化方案,其中引进了对易关系xp—px=ihe~[-(C/M)t]。指出这种方法在推广到C显含时间的情况时将发生困难。为使C显含时间的情况也能统一处理,必须保留海森堡对易关系xp-px=ih,同时假定对振子的作用力中含有与x不对易的部分f_R,并满足对xf_R—f_Rx=ih(C/M)。还具体分析了电子振子。
Resumo:
SOLAR-TERRESTRIAL SCIENCESThe solar-terrestrial sciences study how the solar energy, momentum and mass transfer through the interplanetary space, the earth magnetosphere, the ionosphere and the neutral atmosphere, and their influence on earth environment. The solar-terrestrial sciences are also called, sometimes, the solar-terrestrial physics, solar-terrestrial relations, solar-terrestrial
Resumo:
采用AgNO3和KNO3的混和熔盐作为离子源,系统地研究了K9玻璃离子交换过程中熔盐配比、交换时间和交换温度等工艺参数对波导性能的影响,得到离子交换玻璃波导折射率分布符合高斯函数形式,建立了波导特性与离子交换工艺参数间的联系。测试得到离子交换平板波导的传输损耗为0.45dB/cm,并利用离子交换技术在K9玻璃上制备了一种跑道形谐振腔滤波器,实现了滤波效应。
Resumo:
长周期光纤光栅作为一种损耗型的带阻滤波器,在光纤通信和光纤传感器领域有着广泛的应用。结合长周期光纤光栅的传输特性,利用传输矩阵法对多种长周期莫尔光栅的透射谱进行了理论模拟。分析结果表明,莫尔光栅技术在制作高性能的相移长周期光栅和变迹长周期光栅上有着很好的应用前景。