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41.
42.
阐述了塑料结构壁管的基本情况和国内外现状.重点就扬子石油化工股份有限公司研究院研制的聚丙烯结构壁管专用料的情况进行了介绍。 相似文献
43.
把DCS应用于酸法生产CPE中,描述了DCS的硬件配制,生产中的控制要点及自控方案,在工业化生产中取得了良好效果。 相似文献
44.
45.
Ink‐eliminated sludge flour (IESF), waste residue from the recycling treatments of waste paper, was utilized as a new kind of filler to reinforce polypropylene (PP) in this research work. Different coupling agents, including maleated anhydride grafted PP (MAPP), stearic acid (SA), and titanate (NDZ‐101), were used to increase the compatibility between IESF and PP. By using different measurements, the microstructure, morphology, thermal behaviors, and mechanical properties of the IESF/PP composites were investigated in detail. It was found that IESF, as a nucleation agent, not only induced the crystallization orientation of PP but also accelerate the crystallization rate of PP. Just as indicated in the experiments, the presence of IESF has shown the advantages of increasing the dimensional stability, the hardness and the flexural property, and the presence of coupling agents has a favorable effect on the improvement of dimensional stability. Moreover, the coupling agent has minor influence on the mechanical property, even causes some decrease in the impact strength. Among these three coupling agents, MAPP is found to be the best coupling agent for increasing the interfacial adhesion between IESF and PP, and the MAPP addition makes the PP composite possess the quickest crystallization rate and greatest tensile strength. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 513–520, 2003 相似文献
46.
ECN树脂中的可水解氯含量是决定树脂质量的—个重要指标。本文研究了反应温度、ECH/OCN配比、反应时间和碱用量等因素的影响,取得了规律性的认识,并获得最佳配方,制备出高纯度的ECN树脂系列产品。 相似文献
47.
CeO2 particles confined within the pores of an SBA-15 mesoporous silica host were prepared by incipient wetness impregnation (IMP)
and deposition precipitation (DP) methods. The materials were characterized by XRD, N2-adsorption and temperature programmed reduction (TPR) to evaluate the structure, texture, and redox properties. The preparation
procedure had significant impact on the assembling mode of CeO2 inside the SBA-15 mesopores. A high dispersion of CeO2 particles was achieved via DP, whereas the dispersion of CeO2 prepared by IMP was found to be inhomogeneous and CeO2 partially blocked the pores. The CO conversion in the water-gas-shift reaction was enhanced over 1 wt% Pt supported on CeO2-modified SBA-15 obtained by DP. 相似文献
48.
PBT共混改性研究最新进展 总被引:5,自引:1,他引:5
综述了最近几年国内外聚对苯二甲酸丁二醇酯(PBT)共混改性的研究进展,分类介绍PBT/聚烯烃、PBT/同系聚酯、PBT/液晶、PBT/弹性体、PBT/聚碳酸酯等不同共混体系,讨论了各体系中的相行为、相容性、热稳定性、力学性能等,并对该类共混物的发展趋势作了简要的分析。 相似文献
49.
In a previous study, CETP inhibitory peptide (3 kDa) was isolated from hog plasma. The peptide, synthesized chemically according
to the amino acid sequence of the 3-kDa peptide (designated P28), showed CETP inhibitory activity both in vitro and in vivo [Cho et al. (1998) Biochim. Biophys. Acta 1391, 133–144]. We report herein further unique features of P28 when it was associated with the cholesteryl ester (CE)-donor and-acceptor lipoproteins. Lipoprotein substrates with P28 present in both HDL (as a CE-donor) and LDL (as a CE-acceptor) served as poor substrates, with CE-transfer activity decreased
up to 60% compared to normal substrates without P28. P28 was found to be located in HDL fractions of hog plasma and showed the same electromobility as that visualized by PAGE on
7% polyacrylamide gel under nondenaturing conditions. Addition of apolipoprotein A-1 (apoA-1) or apoB antibody to a normal
CE-transfer mixture did not alter CE-transfer activity. However, addition of apoA-1 or −B antibody to a CETP-inhibition mixture
decreased the inhibitory activity of P28 by ca. 20%. Western blot analysis revealed that P28 was associated only with human and hog HDL among several lipoproteins purified from human, hog, and rabbit. CFTP-inhibition
assays with various lipoprotein substrates revealed that P28 exhibited substrate-specific inhibitory activity. The inhibitory activity of P28 was highly dependent on the type of lipoprotein substrate (whether CE-donor or-acceptor); P28 inhibited CE transfer from HDL to LDL, but it did not inhibit CE transfer from HDL to HDL. 相似文献
50.
论港口危险货物运输装卸作业安全问题 总被引:3,自引:0,他引:3
危险货物作业安全越来越受到人们的关注,从危险货物的分类谈起,分析了危险货物港口运输装卸作业中易引发事故的诸因素和安全作业中应特别注意的几个问题,强调从业单位、从业人员的资质、法律意识和业务素质,制定危险货物事故应急预案等。提出了加强港口危险货物安全管理的有关建议:开展危险源与事故隐患的多层次监控;推进港航危险货物企业建立安全质量标准化体系;创建“抓小放大”的安全管理机制。 相似文献