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61.
为改善复合泡沫塑料的介电性能,采用金属氧化物粒子填充改性双马来酰亚胺空芯玻璃微球复合泡沫塑料得到了高介电常数、低介质损耗因数、低密度、力学性能良好的电介质材料。 相似文献
62.
Ying Quan Mingshan Yang Tongxiang Liang Qin Yan Deshan Liu Riguang Jin 《应用聚合物科学杂志》2007,103(6):3940-3949
Novel composite particles based on nanoscale calcium carbonate (nano‐CaCO3) as the core and polyacrylates as the shell were first synthesized by in situ encapsulating emulsion polymerization in the presence of the fresh slush pulp of calcium carbonate (CaCO3) nanoparticles. Subsequently, these modified nanoparticles were compounded with rigid poly(vinyl chloride) (RPVC) to prepare RPVC/CaCO3 nanocomposites. At the same time, the effects of the reinforcement and toughening of these modified nanoparticles on RPVC were investigated, and the synergistic effect of modified nanoparticles with chlorinated polyethylene (CPE) was also studied. The results showed that in the presence of nano‐CaCO3 particles, the in situ emulsion polymerization of acrylates was carried out smoothly, and polyacrylates successfully encapsulated on the surface of nano‐CaCO3 to prepare the modified nanoparticles, breaking down nano‐CaCO3 particle agglomerates, improving their dispersion in the matrix, and also increasing the particle–matrix interfacial adhesion. Thus, the effects of the reinforcement and toughening of these modified nanoparticles on RPVC were very significant, and the cooperative effect of the nanoparticles with CPE occurred in the united modification system. Scanning electron microscopy analyses indicated that large‐fiber drawing and network morphologies coexisted in the system of joint modification of nanoparticles with CPE. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3940–3949, 2007 相似文献
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64.
目的:阐述实验动物在血液制品生产质量控制过程中应用的重要性。方法:按《中华人民共和国药典》2005年版三部要求及相关项目的技术规范进行血液制品质量控制。结果:血浆数量150吨,可同时生产以下品种的产品,人血白蛋白共30批次,总瓶数约40万瓶(折10g);免疫球蛋白类:共30批次,总瓶数约30万瓶(折2.5g);人纤维蛋白原:共30批次,总瓶数约15万瓶(折0.5g);人凝血酶原复合物:共30批次,总瓶数约12万瓶(折300IU);人凝血因子Ⅷ:共30批次,总瓶数约10万瓶(折200IU)。需使用家兔870只、豚鼠300只小鼠750只。结论:实验动物应用于血液制品生产质量控制发挥了非常重要的作用。 相似文献
65.
Based on analyses of the components of crude oil hydrocarbons and carbon isotopes, the content of normal alkane de-creased from 49.00% to 20.10% when moving from the No.3 to No.5 tectonic belt of the Lenghu area of the Qaidam Basin, while cycloalkanes increased from 30.00% to 52.20% and aromatic and branch chain alkanes increased gradually as well. The maturity of sterane in crude oil is higher than that of its source-rock, which shows that the hydrocarbons were generated from a deep source-rock of high maturity around the tectonic belts of the Lenghu area. The analysis of the characteristics of carbon isotopes also shows that these isotopes of hydrocarbon compounds in the No.4 and No.5 tectonic belt are apparently heavier than those in the No.3 belt. The results of our research show that the hydrocarbons in the No.3 tectonic belt are mainly from a relatively rich sapropelic substance, while the hydrocarbons in the No.4 and No.5 tectonic belt originated mainly from organic matter of a rela-tively rich humic type substance. 相似文献
66.
Paul S. K. Choi Liang T. Fan 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1973,23(7):531-548
Mathematical models are developed for the transient behaviour of encapsulated enzyme reactor systems such as the continuous stirred tank reactor (CSTR) and the packed bed tubular reactor. The rate processes taking place in the encapsulated enzyme bed are approximated by using a combined rate control model of enzyme reaction and membrane diffusion. The change in transient substrate concentration is obtained by using the developed rate expression in the material balance over the substrate as a function of time for the CSTR and as a function of time and position for the packed bed tubular reactor. The effects of various parameters such as the enzymic reaction rate constant, Michaelis constant, diffusional resistance of membranes, and Peclet number on the substrate concentration distribution, which varies with respect to operating time, are investigated. This study affords insight into the transient operating characteristics of the encapsulated enzyme reactor system. The results should be useful in understanding the start-up performance of the reactor systems and to control such reactor systems at desired operating conditions. 相似文献
67.
68.
近年来由于人类生产活动日益加剧,引起的大气气溶胶和臭氧等大气粒子含量的变化对全球气候变化有着重要影响.为了监测上述大气粒子含量,在总结国内外研究现状的基础上,提出使用合理的温控结构来设计制造一款新型多波段太阳辐射测量仪,用来适应国内纬度跨越大、温差大的工作环境.新型太阳辐射测量仪涵盖可见-红外波段,采用九个带通滤光片分别对应两个光电探测器的结构,可以避免探测器相互定标引起的定标误差并减少定标工作量.经ANSYS Workbench热-力耦合仿真,上述太阳辐射测量仪所采用的温控结构在两个极端温度条件下的变形量满足设计要求. 相似文献
69.
Sun Yuxiang Yuan Bo Zhang Yongliang Zheng Wanwen Xia Qingfeng Tang Bojian Zhou Xianzhong 《International Journal of Control, Automation and Systems》2021,19(9):2984-2998
International Journal of Control, Automation and Systems - The reinforcement learning problem of complex action control in multiplayer online battlefield games has brought considerable interest in... 相似文献
70.
Sixty sediment samples were collected from the main Songhua River in three years. Twelve polybrominated diphenyl ether ( PBDE) congeners ( BDE17, 28, 47, 66, 99, 100, 153, 154, 138, 183, and BDE?209) w... 相似文献