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91.
Xiaoxia Zheng 《Polymer Degradation and Stability》2006,91(2):289-297
Nanocomposites of polystyrene, high impact polystyrene, acrylonitrile-butadiene-styrene terpolymer, polypropylene, and polyethylene were prepared using a methyl methacrylate oligomerically-modified clay by melt blending and the thermal stability and fire retardancy were studied. These nanocomposites were characterized by X-ray diffraction, transmission electron microscopy, thermogravimetric analysis and cone calorimetry. The results show a mixed morphology, depending on the polymer. 相似文献
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93.
聚氯乙烯—丁腈橡胶—氯丁橡胶三元共混物的研究 总被引:1,自引:0,他引:1
测定了聚氯乙烯(PVC)-丁脯橡胶(NBR-29)-氯丁橡胶(CR)三元共混物的冲击性能和应力-应变行为,用动态力分析、扫描电和透射电镜研究了共混物的相容性和形态结构。结果表明,NBR-29对PVC,CR有良好的增容作用,三元共混物是部分相容的二相体系,具有良好的抗冲击性能。 相似文献
94.
Hong-Chang Yao Song Gao Li-Min Zheng Xin-Quan Xin 《Journal of solid state chemistry》2004,177(12):4557-4563
Hydrothermal reactions of copper (II) nitrate with 1-hydroxycyclohexanephosphonic acid [C6H10(OH)PO3H2] or Δ1-cyclohexenephosphonic acid [C6H9PO3H2] have resulted in three new copper phosphonates, namely, Cu(C6H10(OH)PO3)(H2O)2 (1), Cu(C6H10(OH)PO3) (2) and Cu(C6H9PO3)(H2O) (3). Compound 1 has a dinuclear structure in which two {CuO5} square pyramids are bridged by two {CPO3} tetrahedra through corner sharing. The dimers are connected through intermolecular hydrogen bonds, forming supramolecular layers. Both compounds 2 and 3 show layer structures typical for metal mono-phosphonates, in which the inorganic metal-containing layers are separated by cyclohexane or cyclohexene groups. The magnetic studies show that ferromagnetic interactions are mediated between copper centers in compound 1. In compounds 2 and 3, antiferromagnetic interactions are dominant. 相似文献
95.
离子敏感场效应晶体管具有若干不同于寻常传感器的特点:超小型、全固态、集成化和自身阻抗变换等。它是一种很有发展前途的传感器。本文了讨论了离子敏感场效应晶体管的分类、结构和性能;评述了1989年以来其在临床医学和流动注射分析等方面的应用。引参考文献67篇。 相似文献
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97.
Li Yan Liang Shao Ping Ren Yi Quan Zheng Man Geng Lu Guangzhou Institute of Chemistry Chinese Academy of Sciences Guangzhou China Key Laboratory of Polymer Materials for Electronics Guangdong China Graduate School of the Chinese Academy of Sciences Beijing China 《中国化学快报》2007,18(2):225-228
A series of novel liquid crystalline epoxides with lateral substituents were cured with anhydrides and the cure kinetics was investigated by non-isothermal DSC technique. The results showed that the lengths of lateral substituents have great effect on the value of Ea. The curing reaction became less active, when the liquid crystalline epoxides have long lateral substituents and were controlled by diffusion at the late stage of cure. A nematic structure was observed by POM and XRD. 相似文献
98.
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100.
Guangyun Zheng Jiemin Jiang Yuping Wu Renxi Zhang Huiqi Hou 《Plasma Chemistry and Plasma Processing》2003,23(1):59-68
Non-equilibrium plasma, which was engendered by dielectric barrier discharge (DBD) was used to analyze the mutual conversion between CO2 and CO. The results showed that the conversion ratio of CO increased monotonously with the increasing voltage. But CO2 was not so. Its conversion ratio reached maximum when the voltage was 3600 V in Ar system. It also showed that the existence of water molecules was more advanageous for the conversion of CO to CO2 in Air system than in oxygen system, and the conversion ratio could reach 75.8% when the relative humidity was 100%. We also discussed the energy yield and energy efficiency, and the result was that high voltage and high concentration of reactant was disadvantageous for energy utilization. 相似文献