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991.
Microstructures of hundreds of micron thick poly(styrene-block-isoprene) copolymer films solution-cast in a cylindrical tube with the solvent evaporation controlled were investigated by transmission electron microscope (TEM), small angle X-ray scattering (SAXS) and optical microscope (OM). In a block copolymer with cylindrical polyisoprene microdomains, the orientation of the cylinders was varied along radial direction of the cylindrical tube. Highly aligned hexagonal arrays of in-plane polyisoprene cylinders were formed with their cylindrical axis parallel to the circumference of the tube in the regimes close to the wall edge. In contrast randomly ordered microdomains were observed at the center of the tube. We have also found that the orientation depends on the solvent evaporation rate and an intermediate rate (∼2.3 nL/s) provides the best orientation. In the case of a block copolymer with a bicontinuous double gyroid structure, we obtained a globally ordered microstructure where [111] crystallographic direction was parallel to the circumference of the tube. For both block copolymers, the area of highly ordered arrays of nanoscopic domains is over 1 mm2. Development of the orientation was explained by coupling two orthogonal fields: (1) The flow of a solution induced by strong capillary force at a meniscus between the cylindrical tube wall and the block copolymer solution and (2) the solvent evaporation. 相似文献
992.
为解决由于电信事业的发展对电信管理网所提出的更高要求,即兼容性、可持续性、综合技术应用性等方面的要求,提供了一种基于TMN架构的电信管理网的设计实现架构,对整个系统的架构进行了概括性的分析。该系统是一个成功应用的商用系统,采用了J2EE架构,对J2EE架构的应用具有一定的启示作用。依照该架构实现的电信管理网系统,无论从软件的复用性,可扩展性及产品的功能特点等指标,均满足了当前电信事业发展的要求。 相似文献
993.
Yu. A. Radin I. A. Grishin T. S. Kontorovich O. B. Panshina A. V. Chugin 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2006,40(2):113-119
Problems arising with connecting the second exhaust-heat boiler to the first exhaust-heat boiler under load in the case of
flow circuits of combined-cycle plants of type PGU-450 are considered. Similar problems exist for two-boiler single-turbine
units of type PGU-325 and for two-boiler single-turbine units of traditional steampower plants with an output of 200–300 MW
upon connection of the second furnace of a two-furnace boiler to the operating first furnace. Analysis of the temperature-induced
stressed state and of the cyclic strength of thick-walled elements of the steam-water conduit of PGU-450 and of two-furnace
boilers of two-boiler single-turbine units with an output of 200–300 MW (the check valve, the inlet header of the water economizer)
is used for determining the steam temperature differences in the high-pressure conduits to the steam turbine and the order
of connection of the second exhaust-heat boiler to the operating fist one. Modes of enabling a two-boiler single-turbine unit
of a combined-cycle plant, which are most “rigid” from the standpoint of thermal strength, are determined.
__________
Translated from élektricheskie Stantsii, No. 2, February 2006, pp. 11–17. 相似文献
994.
995.
基于B/S模式矿山管理信息系统构建技术研究 总被引:3,自引:1,他引:2
在全面分析以往矿山管理信息特点的基础上,提出了基于B/S模式开发矿山信息系统的思路。对基于B/S模式开发矿山信息系统的关键技术及开发步骤进行了详细的介绍。 相似文献
996.
An advanced learning system for interactive simulation of patient cases (ISP) is described. The system was designed to meet specific pedagogical needs where student activation and problem orientation were two of the key issues. The system includes features such as video based illness history-taking function using free text input, highly interactive physiological examination procedures, extensive laboratory tests and detailed user feedback. The system was constructed mainly in Authorware Professional, starting more than 10 years ago, and it is now available in refined versions in different languages. Twelve pedagogical and three technical features were initially defined for the project. All of these aims were fulfilled. The ISP system has been successfully used in education, and in international collaboration, including three applicability field tests. The system is also a powerful research tool for studying for instance medical decision-making. 相似文献
997.
998.
等径弯角挤压工艺(ECAEP)研究现状 总被引:3,自引:0,他引:3
等径弯角挤压是制备块状细晶材料的一种大塑性变形工艺,目前得到国内外高度重视.本文简要介绍了等径弯角挤压工艺的基本原理和变形特点,从理论上对其变形方式和机理进行了分析,并详细介绍了该工艺的应用领域。 相似文献
999.
1000.
本文综术了集成电路工艺的Cu布线中Cu薄膜化学气相沉积(CVD)的研究背景,详细介绍了CVD生长Cu金属薄膜的国内外研究进展及CVD对前趋物的要求,并对前趋物的一些物理、化学性质进行了总结,最后,对薄膜沉积的计算机摸拟作了简要介绍。 相似文献