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41.
A number of molecular beam experiments with the fullerenes are described. Such experiments allow a detailed probing of the interactions between fullerenes and other species and among the fullerenes themselves. Emphasis is placed on work involving photophysics and collisional interactions of the fullerenes. 相似文献
42.
A fast and simple 1H NMR spectroscopic method was developed for the concentration measurement of aromatic, olefinic and aliphatic fractions in gasoline samples. Simultaneously, individual components such as benzene, methyl tert-butyl ether and several dienes could be determined. The method relies on only a few, well-established assumptions about the molecular compositions and is therefore applicable to a broad range of gasolines. It is well suited for laboratories with high sample throughput since measurement time is short and all concentrations are determined within one NMR experiment. The method was applied to commercial gasolines and samples used in European round robin tests. Comparisons of NMR and round robin test results showed excellent agreement. 相似文献
43.
对二聚炔醇化合物DMH的合成、分子结构及缓蚀作用机理进行了论述。因DMH化合物具有独特的分子结构,形成了稳定的络合体系及基团的屏蔽效应,增加了缓蚀被膜厚度及缓蚀体系的化学稳定性,实验证实DMH是酸性介质中的高效缓蚀剂。 相似文献
44.
本文对生产高纯度丁烯-1的Alphabntol工艺进行了技术经济评价,认为该工艺条件简单、反应条件温和,而且投资少,所以很适合事在发展中国家应用。 相似文献
45.
Santosh D. Wanjale 《Polymer》2006,47(18):6414-6421
Poly(1-butene)/MWCNT nanocomposites were prepared by simple melt processing technique. Crystallization, crystal-to-crystal phase transformation and spherulitic morphology were studied using differential scanning calorimetry (DSC), wide angle X-ray diffraction (WAXD) and optical microscopy (OM). The non-isothermal crystallization exhibited higher values of Zt derived from Avrami theory and lower values of F(T) obtained from Avrami-Ozawa analysis, while the isothermal crystallization revealed a significant increase in crystallization temperatures and lower crystallization half times compared to pristine PB. The observed changes in the crystallization kinetics were ascribed to the enhanced nucleation of PB in the presence of MWCNT. The nucleating activity calculated from the non-isothermal crystallization data revealed that the MWCNTs provide an active surface for the nucleation of PB. The optical micrographs exhibited significantly smaller crystallites with disordered morphology for the nanocomposites compared to the well defined spherulitic morphology for pristine PB. The rate of phase transformation from kinetically favored tetragonal to thermodynamically stable hexagonal form was noticeably enhanced as evidenced by the reduction in the half time for phase transformation from 58 h to 25 h for PB reinforced with 7% MWCNT. 相似文献
46.
用金属卟啉络合物引发合成高分子量聚醚 总被引:2,自引:1,他引:2
介绍了用四苯基卟啉铝络合物催化体系合成高分子量聚醚的方法。该聚合过程显示出一种持续特性。产物具有均一的链长和极窄的分子量分布,且数均分子量Mn可通过改变单体与引发剂的摩尔比来控制。 相似文献
48.
设计一种TDM over IP的技术系统。该系统用FPGA将E1数据包通过串并转换到千兆以太网数据包,经IP网传输到终端设备,再通过并串转换将以太网数据包转换成E1数据包完成传输。经过软件和硬件测试验证了此系统在千兆以太网上传输的可行性,系统没有出现误码,固有输出抖动是0.55UI,最大峰值抖动指标均满足ITU-G.823标准要求。 相似文献
49.
The oxidation kinetics and structure of the oxide scales formed on high-density SiC were studied in molecular oxygen at 740 Torr and in a glow-discharge oxygen plasma at 0.1 Torr at temperatures of 1000, 1100, and 1200°C. The monatomic oxygen formed by the glow discharge markedly increased the reaction rate and the vaporization of some of the oxidation products. The marked differences in kinetics suggest that the rate-controlling step during oxidation in molecular oxygen is the dissociation of adsorbed diatomic oxygen to the monatomic species. Films formed in molecular oxygen were mostly amorphous SiO2 with small inclusions of SiC and graphite, whereas films formed in dissociated oxygen were primarily amorphous SiO2 containing SiO, S2O3, and the coesite form of SiO2. 相似文献
50.