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合成了6种钨硅杂多配合物异构体α、βi-M3H2[SiW11(NbO2)O39]·H2O(M=Me4N+(TMA),Bu4N+(TBA),Et4N+(TEA);βi=β1,β2,β3)。IR光谱、UV光谱、极谱、I--S2O32-滴定证明合成的杂多配合物中有NbO2基存在, 183W NMR光谱证明其阴离子具有Keggin结构,催化实验结果表明,合成的化合物对烯烃环氧化反应具有催化活性,且过氧杂多配合物的催化活性高于非过氧杂多配合物,β异构体的催化活性高于α。 相似文献
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Supermolecular compounds of glycine monosubstituted heteropolytungstates isomer with Keggin structure βi-K6-n(HGly)n[SiW11M(H2O)O39]·xH2O (M=Co2+, Ni2+; βi=β2, β3) were synthesized and characterized by means of elementary analysis, IR, UV, TG-DTA, X-ray diffraction, polarography and CV. The results indicate that glycin combines the electrostatic effect with heteropolytungstates isomer. The heteropoly anion still remains its Keggin structure in supermolecular compounds. The electrochemical behavior of the compound in 1 mol·L-1 HAc-NaAc shows that two redox waves correspond to two two-electron processes attributing to the reduction of [SiW11Co(H2O)O39]6-. Steady-state fluorescence spectrum shows two intenser fluorescence emission peaks in 447 nm and 486 nm appeared after the supermolecular compound being excited by the excitation wavelength in 274 nm. 相似文献
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二价铬或锰取代的硅钨杂多酸异构体的聚苯胺掺杂材料的制备及其热稳定性和荧光性能的表征 总被引:1,自引:0,他引:1
预先制备了由二价铬或锰取代的硅钨杂多酸钾盐的α及βi(βi=β1,β2及β3)异构体,然后在室温及无酸的条件下与聚苯胺进行固相掺杂,用红外光谱法、紫外-可见分光光度法、X射线衍射法、差示热重量法及分子荧光光度法对所得的掺杂材料的结构、热稳定性及荧光性能等特性作了表征. 相似文献
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PANI/TiO_2/SiW_(12)复合光催化剂的制备、表征及其光催化性能 总被引:1,自引:0,他引:1
以(NH4)2S2O8为氧化剂,通过化学氧化法在TiO2颗粒表面包覆聚苯胺(PANI)薄膜制得PANI/TiO2。通过静电自组装方法将SiW412-键合在PANI/TiO2表面,制备了一种新型的复合光催化剂PANI/TiO2/SiW12(1),用UV-Vis,FT-IR,XRD和SEM等对1的结构和光吸收性能进行了表征。以刚果红为目标降解物,研究了1在太阳光下的光催化性能。结果表明,PANI的敏化作用拓宽了TiO2的光响应范围,提高了光能的利用率,增强了复合材料的光催化活性。1的光催化活性明显高于TiO2和PANI/TiO2,90 min降解率达83.94%。 相似文献
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合成了Keggin结构锌取代杂多钨硅酸盐三乙醇胺电荷转移配合物α-Si W11Zn/TEA,用元素分析,IR,XRD和TG-DTG对其进行了表征。同时,采用TG-DTG技术研究了标题化合物在氮气气氛中的热分解机理及非等温动力学,结果表明,α-Si W11Zn/TEA的分解反应共有3个阶段,第一阶段分解反应的表观活化能Ea与指前因子ln A分别为:4.81k J·mol-1和7.36 min-1,机理函数为G(α)=α+(1-α)ln(1-α);第二步分解过程的表观活化能Ea与指前因子ln A分别为:7.27 k J·mol-1和11.48min-1,机理函数为:G(α)=[-ln(1-α)]0.1;第三步分解过程的表观活化能Ea与指前因子ln A分别为17.16 k J·mol-1和8.999 min-1机理函数为:G(α)=1-(1-α)4。 相似文献
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铁取代钨硅酸盐位壹异构体的合成、表征及电化学性质 总被引:3,自引:0,他引:3
The four heteropoly isomers K3H2 [α-,βi-SiW11 Fe (H2O) O39]·χH2O (βi =β1,β2,β3) were prepared and Characterized by elementary analysis, IR and UV Spectroscopy. Its electrochemical behavior in aqueous solution has been discussed. The order of Polarographic half-wave potential E1/2 of heteropoly anions is as follows: β2>β1>β3>α. Its reduction process involves an one-electron reduction of Fe (Ⅲ) and a pair of two-electron reduction of W (Ⅵ). Epolidation of maleic acid with H2O2 Catalyzed by heteropoly positional isomers was studied. β3 isomers are the most active 相似文献
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