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41.
L. C. Feng W. Z. Shao L. Zhen N. Xie V. V. Ivanov 《International Journal of Applied Ceramic Technology》2007,4(5):453-462
Cu2 O/ x Cu ( x =0–25 wt%) cermets were evaluated as a novel partially inert anode for aluminum (Al) production. The physical and mechanical properties, including the compressive strength, flexural strength, thermal expansion coefficient, thermal conductivity, and dc electrical conductivity were tested at room temperature and at temperatures up to 950°C. The coefficient of thermal expansion, compressive strength, flexural strength, thermal conductivity, and electrical conductivity of Cu2 O/Cu cermets increased with increasing Cu content. High-temperature electrical conductivity measurements showed that with increasing temperature, the electrical conductivity increased when the Cu content was below the percolation threshold, while it decreased when the Cu content was above the percolation threshold. A relatively stable CuAlO2 layer formed on the cermet surface during electrochemical testing, and the corrosion rate of this anode was estimated to be about 1.8–1.9 cm/year in Al production. 相似文献
42.
顺酐化SBS的钠离聚体形式与丙烯酰胺的乳液接枝共聚 总被引:2,自引:0,他引:2
研究了顺酐化SBS的钠离聚体与丙烯酸胺以过氧化苯甲酰为引发剂的乳液聚合,得到了共聚的较佳条件.并以IR及DSC表征了试样的组成和多相结构. 相似文献
43.
ABSTRACT In this research, the effect of particle size on the surface oxidation and flotation behavior of galena in the lime system was studied. Coarse (?0.074 + 0.038 mm), intermediate (?0.038 + 0.025 mm) and fine (?0.025 mm) galena particles were used in the experiment. The dissolution tests, flotation tests, and sorption tests were accomplished. Through further analysis by XPS, the effect of particle size and lime was observed. The decrease of mineral particle sizes increased the adsorption ratio of collector and the dissolution of galena, while the hydrophilic product OH?/Ca(OH)+ produced by dissolution occupied the dominant position, which led to the minerals hydrophilic. 相似文献
44.
45.
Biodiesel was produced by transesterification of soybean oil with methanol using ZnO loaded with KF as a solid base catalyst.
It was found that the catalyst with 15 wt.% KF loading and calcined at 873 K showed the optimum activity. XRD, IR and Hammett
indicator method were employed for the catalyst characterization. The results showed the activity of the catalysts was correlated
with their basicity. The influence of various reaction variables on the conversion was also discussed. 相似文献
46.
石灰石在煤气化过程中的催化和固硫作用 总被引:1,自引:1,他引:1
基于CaO在煤气化中的催化和固硫作用,以及石灰石加热分解的性质,石灰石有可能作为煤气化过程中的催化剂和固硫剂。本文根据国内外对石灰石在煤燃烧和煤气化中作用的研究,从石灰石结构、Ca/C,Ca/S,可能的反应机理等几个方面进行了介绍和分析,并指出需进一步研究的内容。 相似文献
47.
In this study, the reaction kinetics of asymmetric polymer-polymer interface was experimentally and theoretically studied. A new rheological method correlating the change of rheological property of reactive system with the conversion of the in situ formed copolymers was applied to study the reaction kinetics of PBT/epoxy reactive system. Then, the new method was proved to be useful by comparing its results with that obtained from the conventional endgroup determination method. Moreover, the conversion of PBT/epoxy reactive system from rheological method could be well fitted by the numerical analysis, from which the kinetic constant and the diffusion constant of epoxy in PBT could be determined simultaneously. 相似文献
48.
Modification of silk with aminated polyepichlorohydrin to improve dyeability with reactive dyes 总被引:1,自引:0,他引:1
Xie Weibin He Jinxin Chen Shuilin Chen Guoqiang Peng Taozhi 《Coloration Technology》2007,123(2):74-79
Reactive dyes have almost complete exhaustion and ideal fixation on aminated polyepichlorohydrin pretreated silk without addition of salt or alkali. The effects of varying pretreatments and dyeing conditions were studied. The dyeing behaviour of CI Reactive Red 15 on modified silk under pH 6 was investigated. Dyeings of modified silk showed good wash fastness, dry and wet rub fastnesses as well as light fastness. The quality of the dyed silks obtained after pretreatment was shown to be satisfactory and the dyeing effluent was less polluted. 相似文献
49.
Lijin Xie Junfeng Ma Jun Zhou Zhongqiang Zhao Hua Tian Yonggang Wang Jiantao Tao Xiaoyi Zhu 《Journal of the American Ceramic Society》2006,89(5):1717-1720
Well-crystallized bismuth tungstate (Bi2 WO6 ) powders with different morphologies were successfully synthesized via a low-temperature molten salt method. The powders were characterized by X-ray diffraction, transmission electron microscopy, and UV-Vis, respectively. It was found that the variation of morphology of the obtained Bi2 WO6 powder mainly depends on the different reaction temperatures and the weight ratio of LiNO3 –NaNO3 salt to precursor. In addition, the UV-Visible absorption spectra showed that the synthesized powders had strong light absorption properties not only in the ultraviolet light but also in the visible light region. 相似文献
50.
Alumina supported vanadia catalysts (V/Al) for selective oxidehydrogenation of ethylbenzene with CO2 were prepared by impregnation method. During preparation the effect of promoters and calcined temperature was investigated,
it was found these two items had a strong influence on the activity of V/Al catalysts. Dehydrogenation reaction with CO2 was happened in the fixed-bed reactor at 450 °C. Results showed that 15.2% ethylbenzene conversion and 99.2% styrene selectivity
were acquired when V2K/Al catalyst was used. 相似文献