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101.
Using nickel-2,2′-dipyridyl complex as a template, N-vinyl-2-pyrrolidone as the metal coordination functional monomer, and ethylene glycol dimethacrylate as the crosslinker, polyvinylidene fluoride (PVDF) hollow fiber ultrafiltration membrane as the supported membrane, metal complex imprinted polymeric membranes were prepared. The association constant of template-monomer interaction in the prepolymerization solution was estimated to be 4.38 × 104 (L/mol)2 by spectrophotometric titration analysis. The attenuated total reflection Fourier transform infrared spectroscopy and scanning electron micrograph characterization indicated that the surface of the support PVDF membrane was completely coated by the imprinted polymer layer after modification. The imprinted membranes exhibited the selective permeability for the template in certain nickel acetate solution. The molecularly imprinted membranes gave higher permeation separation factors at about pH 6, whereas increasing pressure would lower the separation ability. The effects of ion concentration, cations and counterions, ligand selectivity, pH, and trans-membrane pressure were investigated and the permeation performances of the imprinted membranes could be regarded as facilitated transport mechanism. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
102.
稀散金属镓锗在选冶回收过程中的富集行为分析 总被引:3,自引:0,他引:3
凡口铅锌矿稀散金属镓锗主要是以类质同像形式存在于闪锌矿中,如何有效地综合回收镓锗是凡口矿建矿以来研究的主要课题之一。针对凡口矿综合回收稀散金属镓锗的历史、现状与进展,重点研究了镓锗在选矿回收和湿法冶炼过程中的富集行为及走向,为开发镓锗综合回收新技术提供理论指导,从而提高企业经济效益。 相似文献
103.
介绍了纳米金属氧化物的制作技术,纳米粉末团聚问题的解决以及纳米金属氧化物用于涂料中所引起的神奇功能。同时综述了国内外开发纳米涂料的现状。 相似文献
104.
105.
This paper presents the results of an experimental investigation undertaken to evaluate different purging solutions to enhance the removal of multiple heavy metals, particularly chromium, nickel, and cadmium, from a low buffering clay, specifically kaolin, during electrokinetic remediation. Experiments were conducted on kaolin spiked with Cr(VI), Ni(II), and Cd(II) in concentrations of 1,000, 500, and 250 mg/kg, respectively, which simulate typical electroplating waste contamination. A total of five different tests were performed to investigate the effect of different electrode purging solutions on the electrokinetic remedial efficiency. A constant DC voltage gradient of 1 V/cm was applied for all the tests. The removal of heavy metals from the soil using tap water as the purging solution was very low. When 1 M acetic acid was used as the purging solution in the cathode, the removal of chromium, nickel, and cadmium was increased to 20, 19, and 13%, respectively. Using 0.1 M ethylene diamine tetraacetic acid as the purging solution in the cathode, 83% of the initial Cr was removed; however, the nickel and cadmium removal was very low. A sequentially enhanced electrokinetic remediation approach involving the use of water as a purging solution at both the anode and cathode initially, followed by the use of acetic acid as the cathode purging solution and a NaOH alkaline solution as the anode purging solution was tested. This sequential approach resulted in a maximum removal of chromium, nickel, and cadmium of 68–71, 71–73, and 87–94%, respectively. This study shows that the sequential use of appropriate electrode purging solutions, rather than a single electrode purging solution, is necessary to remediate multiple heavy metals in soils using electrokinetics. 相似文献
106.
HouDianguo 《中国炼油与石油化工》2003,(2):51-56
Reduction of sulfur content in FCC gasoline was studied in a fixed fluid bed (FFB) unit by using metal-modified LV-23 FCC catalyst. The results showed that the sulfur content in FCC gasoline could be reduced with LV-23 catalyst modified with zinc, palladium, zinc-palladium, zinc-cobalt, and zinc-nickel. Among these metals or metal combinations, palladium-containing catalyst was the most effective. Desulfufization of the heavy fraction of FCC gasoline was more effective than full-range gasoline under the same conditions with palladium-containing catalysts. A high reaction temperature was favorable to desulfurization, but it would reduce the yield of liquid product. After desulfurization reaction, the olefm content of product gasoline decreased while the aromatic and iso-alkane contents increased. Removal of thiophene and benzothiophene is higher. 相似文献
107.
Effect of Rare Earth Elements on Thermal Fatigue Property of Low Chromium Semi-Steel 总被引:3,自引:0,他引:3
The effect of rare earth elements on eutectic carbide‘s morphology of low chromium semi-steel in as-cast state and after heat treatment was investigated, and accordingly, the thermal fatigue property of this material was studied. The results show that RE can improve the eutectic carbide‘s morphology, inhibit the formation and propagation of thermal fatigue cracks, therefore, promote the thermal fatigue property, which is more noticeable in case of the RE modification in combination with heat treatment. The optimal thermal fatigue property can be obtained when treated with 0.2% RE modification as well as normalization at 950℃ for 3h. 相似文献
108.
高浓度焦化废水的预氧化-混凝处理研究 总被引:3,自引:0,他引:3
焦化废水成分十分复杂,污染物浓度高,性质非常稳定且水量大,是典型的难降解有机废水。使用H2O2为氧化剂,FeSO4.7H2O为催化剂的Fenton氧化法对钢铁焦化厂废水的终冷水进行了试验研究,氧化处理后用FeCl3为混凝剂对COD,NH3-N,色度及浊度的去除率进行了系统的考查。确定了氧化反应的影响因素和最佳的混凝实验条件。结果表明:当pH值控制在3左右,反应时间为30 min,反应温度为80℃,焦化废水的COD,NH3-N,浊度和色度去除率分别达到了93.1%,96.2%,90.8%和90.2%。 相似文献
109.
从分析修磨过程运动学和单个磨粒切削入手,建立了磨削深度与磨削过程诸参数(如工艺、材料性能、砂轮性能等)的关系表达式,从而建立起金属切除率与各单项参数的定量关系,为改善或提高修磨效率和修磨过程控制提供了有意义的根据。理论分析与实验结果吻合良好。 相似文献
110.
重金属污染物动态吸附试验及数学模拟 总被引:3,自引:0,他引:3
本文采用泥沙动力学中Rouse等人用来研究泥沙浓度沿垂线分布的装置。对泥沙吸附重金属污染物进行了动态模拟。试验分有底泥和无底泥两种情况。研究中发现在Rouse装置的水力、泥沙条件下泥沙吸附重金属污染物达到平衡状态需要6小时以上,由极坐标下的重金属迁移转化数学模型方程,在本文具体试验条件下进行数值求解,计算结果和试验结果合良好,说明数学模型是正确合理的试验是可靠的。计算时依据室内静态试验结果,对动态 相似文献