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951.
N503萃淋树脂吸萃铟的研究 总被引:6,自引:0,他引:6
考察了N_(503)萃淋树脂在盐酸、氢溴酸、硫酸-溴化钠体系中对铟的吸萃性能,研究了N_(503)萃淋树脂在氢溴酸体系中吸萃铟的动力学和机理,发现N_(503)萃淋树脂吸萃铟的反应按假一级反应进行,并符合Freundlich等温吸附式。吸附平衡和红外光谱研究发现N_(503)萃淋树脂吸附铟的反应按下式进行: 相似文献
952.
用溶胶凝胶法制备了钙钛矿型氧化物SrRuO3,热重分析和X射线衍射分别对制备过程和产物进行了分析和表征。采用循环伏安、计时电流和交流阻抗方法测试了所得产物对常温下碱性介质中乙醇电化学氧化的催化性能。循环伏安曲线、计时电流和交流阻抗结果表明:在乙醇溶液中,阳极电流密度明显大于氢氧化钾溶液中的阳极电流密度,并且随着电极中SrRuO3含量的增加,电流密度也大幅度增加,在乙醇溶液中,SrRuO3电极的电荷迁移阻抗明显降低。SrRuO3对乙醇电化学氧化具有良好的催化作用。 相似文献
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本文研究了二甲亚砜(DMSO),二甲替甲酰胺(DMF)吡啶(py)等溶剂对[Co(acac)_2·2H_2O]载氧和氧化性能的影响.实验证明[Co(acac)_2·2H_2O]与O_2的反应第一步为可逆载氧,而第二步为不可逆载氧.用元素分析和波谱研究了[Co(acac)_2·2H_2O]在溶剂中的存在形态和热力学性质。用配位场理论计算了[Co(acac)_2·2H_2O]在溶剂中的各种配位场参数。动力学的研究表明,[Co(acac)_2·2H_2O]在DMF溶剂中O_2的反应发生一级半过程,一级为[Co(acac)_2·2H_2O]半级为O_2.反应的动力学方程为v=k[Co(acac)_2·2H_2O]·P_(o_2)~(0.41).反应的表观活化能为44.8千焦/摩尔,波谱的分析结果证实,氧化反应的主要产物为[Co(acac)_3] 相似文献
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原子簇化合物[WS4Cu3Br(bipy)2]的晶体结构和非线性光学性质 总被引:1,自引:0,他引:1
The title cluster compound [WS4Cu3Br(bipy)2] has been synthesized by the reaction of (NH4)2[WS4], CuBr and 2,2′-bipy in DMF solution. Single crystal X-ray diffraction data show that the compound has a nest-shaped structure. Nonlinear optical properties (NLO) of the cluster were investigated by a Z-scan technique with a pulsed laser at 532nm. The cluster exhibits the strong NLO absorption and a self-defocusing effect (effective non-linear absorption coefficient, α2eff=7.3×10-11mW-1; effective non-linear refractive index, n2eff=3.9×10-11esu) when measured in a 6.0×10-4mol·dm-3 DMF solution. CCDC: 200397. 相似文献
960.
Ag-modified La0.6Sr0.4MnO3 catalysts were prepared and their catalytic performance for deep oxidation of CH4 and CH3OH at low concentrations were investigated. The results showed that the La0.6Sr0.4MnO3 host catalyst with the perovskite-type nano-crystallite structure displayed considerably high catalytic activity for deep oxidation of CH4 and CH3OH at low concentrations. Ag modification to the La0.6Sr0.4MnO3 host catalyst resulted in significant enhancement of the catalyst activity, making the T95 (the reaction temperature needed for conversion of 95%of CH4 or CH3OH) lowered down to 735K (for CH4) and 421K (for CH3OH) from 813 and 465 K over the Ag-free system under the reaction conditions:0.1MPa,CH4/O2/N2=2/12/86(molar ratio),GHSV=45000 h-1 and CH3OH/O2/N2= 0.2/1.0/98.8 (molar ratio),GHSV=58000 h-1,respectively.The carbon containing product was almost CO2 and the contents of HCHO and CO in the reaction exit gas were both under GC detectable limit in both cases.
The results of spectroscopic characterization indicated that modification by proper amount of Ag-dopant did not change the perovskite structure of the La0.6Sr0.4MnO3 host catalyst as a whole. Interaction of Ag-dopant with the surface of the host catalyst,La0.6Sr0.4MnO3,was in favor of high dispersion of the Ag component at the catalyst surface and led to the oxidation of part of the Mn3+species to Mn4+,resulting in an increase of amounts of the reducible Mnn+ species and a decrease of their reduction temperature. On the other hand, this interaction led also to enhancement of adsorption ability of the catalyst toward O2 at relatively low temperature. High activity of the Ag modified La0.6Sr0.4MnO3 catalyst for CH4 and CH3OH complete oxidation was closely related to high redox-activity of the catalyst and its prominent adsorption-activation ability to O2 at relatively low temperatures. 相似文献
The results of spectroscopic characterization indicated that modification by proper amount of Ag-dopant did not change the perovskite structure of the La0.6Sr0.4MnO3 host catalyst as a whole. Interaction of Ag-dopant with the surface of the host catalyst,La0.6Sr0.4MnO3,was in favor of high dispersion of the Ag component at the catalyst surface and led to the oxidation of part of the Mn3+species to Mn4+,resulting in an increase of amounts of the reducible Mnn+ species and a decrease of their reduction temperature. On the other hand, this interaction led also to enhancement of adsorption ability of the catalyst toward O2 at relatively low temperature. High activity of the Ag modified La0.6Sr0.4MnO3 catalyst for CH4 and CH3OH complete oxidation was closely related to high redox-activity of the catalyst and its prominent adsorption-activation ability to O2 at relatively low temperatures. 相似文献