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91.
A novel chelating resin containing sulfoxide and diethylene glycol, poly{4‐vinylbenzyl‐[2‐2‐(hydroxyethyl)ethoxyl]sulfoxide} (PVESO) was synthesized using chloromethylated polystyrene (PS‐Cl) as material. Its structure was characterized by elemental analysis, infrared spectra, and scanning electron microscopy (SEM). The adsorption capacities of the resin for Hg2+, Ag+, Cu2+, Zn2+, and Pb2+ at various pH values were determined. The maximum adsorption capacities for Hg2+ and Ag+ were 1.56 and 0.75 mmol g?1 respectively. The resin had high selectivity for Hg2+ and Ag+ over the pH range 1.0–7.0. The adsorption capacities for Hg2+ and Ag+ under competitive condition were also determined by batch experiment method. In addition, the adsorption kinetics of the resin towards Hg2+ at different temperatures was also investigated. The results showed that the adsorption rate was governed by film diffusion at 20°C and 25°C, by particle diffusion at 30°C and 35°C. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 6054–6059, 2006  相似文献   
92.
The PbO2 and F-doped PbO2 (F-PbO2) film electrodes have been prepared by an electrodeposition process onto platinum substrate. The changes of their electrochemical activity for oxygen evolution (OE) reaction with accelerated electrolysis time have been studied. The results show that the activity of the electrodes decreases with increasing electrolysis time. This can be attributed to the conductivity variations, which are caused by the decrease of the oxygen vacancy concentration in PbO2 films during OE. The mechanism of the decrease of the oxygen vacancies has been investigated. For F-PbO2 film electrodes, though its electrochemical activity is somewhat lower than that of undoped one, its activity stability is much higher in comparison with that of PbO2. The influence of F doping on the activity of PbO2 film electrodes has been also discussed.  相似文献   
93.
New parameters, light transmission rate and minimum light transmissions, are proposed. These two parameters reflect the characteristics of the membrane‐forming system and the formation process of the membranes by phase inversion. The relationship between the light transmission and the porous structure of the membrane can be explained by the geometrical optics principles. Variation of the two parameters combining Reuvers's phase separation theory provided a convenient analytical method to predict effectively membrane morphologies. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 174–181, 2003  相似文献   
94.
农作物秸秆增强氟石膏复合材料的微观结构研究   总被引:1,自引:0,他引:1  
将玉米秸秆加入改性后的氟石膏中,研究改性剂、玉米秸秆对氟石膏复合材料结构性能的影响;并用苯丙乳液对玉米秸秆纤维进行表面处理,用以改善基体材料和增强材料的界面结合状况,由此显著提高制品性能。  相似文献   
95.
以三氯氧磷和环氧乙烷为原料,在三组份催化剂(JC-1)的催化下合成三(β-氯乙基)磷酸酯,产品的纯度和收率都高。探讨了影响产率的几个因素,工艺简便,易于工业化。  相似文献   
96.
97.
The corrosion behavior of pure aluminum in inhibited and uninhibited 4 MKOH was investigated by means of hydrogen collection, polarization curve measurement and electrochemical impedance spectroscopy (EIS). The results showed that the corrosion of pure aluminum was greatly inhibited by the addition of ZnO and dimethyl amine epoxy propane (designated as DE). EIS and EDAX analyses revealed that ZnO produces its effect by depositing on the aluminum surface, which increases the overpotential of hydrogen evolution. It was also found that the addition of DE could greatly improve the deposition of zinc layers.  相似文献   
98.
南小英  曹南萍  刘江华 《陶瓷》2005,(11):33-35,37
从技术、经济、生态、政策等角度,对采用氧化铝和硅酸铝质工业废料制取耐磨陶瓷作了全面、系统的分析研究,论证了废渣制瓷技术上的可行性,阐明了经济上和生态上的优越性,提出了解决具体问题的办法。  相似文献   
99.
The confined etchant layer technique has been applied to fabricate complex three-dimensional microstructures on nitinol for the first time. HF and HNO3 were locally and simultaneously electrogenerated at the mold surface to etch a nitinol workpiece. NaOH was used as an efficient scavenger to confine the etchant close to the mold. Cyclic voltammetry was employed to study the electrochemical behavior of a Pt electrode in the etching solution in order to choose an appropriate potential for etchant generation on the mold. The thickness of the confined etchant layer was estimated to be several micrometers by inspecting the deviation of the sizes of the etched spots from the sizes of those on the microelectrode. Thus, the composition of the electrolyte could be optimized for better etching precision. By optimizing the composition of the electrolyte, complex microstructures on a Pt-Ir mold bearing the logo “XMU” of Xiamen University were successfully fabricated on nitinol. The etched patterns were approximately negative copies of the mold, and the precision of duplication could easily reach the micrometer scale.  相似文献   
100.
带式输送机系统的设计与设备选型(一)   总被引:1,自引:0,他引:1  
1通用带式输送机技术的发展情况 带式输送机与其他运输方式相比具有运距长,能力大,投资省,运费低,操作简单安全,管理维修容易,能耗低,污染小等优势而逐渐成为各行业物料搬运的主要手段。高强度的钢绳芯带式输送机因其为矿山开采和矿石输送工艺创造了十分有利的条件而在各种矿山外部输送中得到快速发展。近年来随着水泥厂规模迅速扩大,带式输送在水泥行业已成为矿石原料输送的首选方案。  相似文献   
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