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101.
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
102.
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
103.
104.
新桥硫矿首次在国内推行露天开采下盘无台阶采矿新工艺,该工艺具有剥岩少、基建快、出矿早、采矿工程延深快等特点。由于该工艺具有独特的靠帮方式和端部过渡方式,需严格控制底盘因爆破而导致的岩体滑动。该工艺的实施已取得了显著的经济效益。 相似文献
105.
纤维素科学与技术研究进展 总被引:3,自引:0,他引:3
梁锋 《纤维素科学与技术》1993,1(3):1-14
本文综述纤维素科学与技术的研究进展。阐述了纤维素结构、纤维素的合成、纤维素液晶、功能纤维素、纤维素溶剂、纤维素裂解和纤维素的废物利用等的最新动态。 相似文献
106.
107.
刘峰 《硫磷设计与粉体工程》2004,(5):15-18
贮仓是许多工业过程中的常用设备,起拱是贮仓使用时常出现的故障,如何解决起拱问题是贮仓设计的关键,除常采取增大仓壁倾角、设置破拱装置等方法外,设计成曲线贮仓也是行之有效的措施之一。分析了指数曲线贮仓的工作原理和特点,建立了仓壁指数曲线方程,阐述了设计步骤与注意事项,并举例说明。 相似文献
108.
Heat‐curable silicone rubber (HCSR) was prepared by using vinyl‐containing silicone resin (VSR) as the crosslinking agent instead of polyvinylsilicone oil (C gum). Mechanical properties and crosslink density of the vulcanizates were measured. The results indicate that VSR is a good crosslinking agent for HCSR. The tensile strength, tearing strength, elongation at break, and hardness of the vulcanizate can reach 10.2 MPa, 29.1 kN/m, 720%, and 58 SHA, respectively. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 3123–3127, 2002; DOI 10.1002/app.10054 相似文献
109.
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
110.
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