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31.
本文首次将统计热力学的Weeks-Chandler-Anderson(简称WCA)微扰理论应用于非极性液体定容比热容和定压比热容的推算,用一些液体的p-v-T实验数据拟合了理论中所用LJ势能函数的势能参数,并提出一个通用关联式。本文方法具有通用性,在编制的计算程序中只需输入物质的临界温度、临界比容、偏心因子等就能算出相应的比热容,工程应用十分方便。 相似文献
32.
Hao Liang Zhiqiang Zheng Zengchang Li Jie Xu Biao Chen Hui Zhao Qijin Zhang Hai Ming 《应用聚合物科学杂志》2004,93(2):681-685
A step‐index polymer optical fiber (SI POF) containing Rhodamine B in poly(methyl methacrylate) (PMMA) has been fabricated by a preform technique. Fluorescence of different fiber lengths were observed and discussed. A high gain (23 dB) for a SI POF with 60‐cm length, 400‐μm diameter was obtained. The Rhodamine B content of the doped SI POF is 5 ppm‐wt. The signal wavelength providing the highest gain for a 60 cm SI POF is around 630 nm, and the optimum fiber length is about 60 cm at 10 kW launched pump power. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 681–685, 2004 相似文献
33.
Liang Xu Xuhai Li Yihang Cui Zhiguo Li Qingyun Chen Chuanmin Meng Haibing Zhang Jianbo Hu Qiang Wu 《Ceramics International》2021,47(15):21008-21012
Ti3SiC2 is of interest due to its unique dual nature reminiscent of both brittle ceramics and ductile metals at ambient conditions. In this work, plate-impact experiments have been performed to study the dynamic behavior of Ti3SiC2 under shock compression up to 112 GPa by using laser velocity interferometer and electric pin techniques. Hugoniot elastic limits (HEL), spall strength, and Hugoniot equations of state have been obtained based on measured particle velocity profiles and shock wave velocities. The ratio of spall strength to HEL for Ti3SiC2 is larger than brittle ceramics but smaller than metals. This result indicates that the dual nature of Ti3SiC2 remains at least up to 10 GPa. On the other hand, the linearity of the Hugoniot equation of state, , suggests that the initial structure of Ti3SiC2 should be stable up to 112 GPa, in contrast to the result reported by Jordan et al. [J. Appl. Phys., 93 (2003) 9639]. 相似文献
34.
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
35.
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
36.
37.
ZHENG Nan YANG Ping WANG QiYi YANG ZhongHai & HUANG Nan Key Laboratory of Advanced Technology for Materials of Education Ministry Key Laboratory of Artificial Organ Surface Engineering of Sichuan School of Materials Science Engineering Southwest Jiaotong University Chengdu China 《中国科学:信息科学(英文版)》2010,(1)
Microgrooves were prepared on Si(100) surface by photolithography and wet etching.Subsequently,Si-N-O films were deposited on the microgrooves by unbalanced magnetron sputtering(UBMS) and micro-patterned surfaces of Si-N-O films were obtained.The size of the micropatterns was measured by surface profilometer.The chemical composition of Si-N-O films were characterized by X-ray photoelectron spectrometry(XPS) and the wettability of the micropatterned surfaces was evaluated by contact angle measurement.The beh... 相似文献
38.
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
39.
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
40.