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CATIONIC RING-OPENING POLYMERIZATION OF TETRAHYDROFURAN WITH KEGGIN-TYPE HETEROPOLYCOMPOUNDS AS SOLID ACID CATALYSTS 被引量:4
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作者 Ahmed Aouissi Salim Salem Al-Deyab Hassan Al-Shehri 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2010年第3期305-310,共6页
Three Keggin-type heteropolyanions, namely H3PMo12O40-13H2O, (NH4)3PMo12O40·4H2O and H3PW12O40·13H2O were prepared and tested in the ring-opening polymerization reaction of tetrahydrofuran. The effects of ... Three Keggin-type heteropolyanions, namely H3PMo12O40-13H2O, (NH4)3PMo12O40·4H2O and H3PW12O40·13H2O were prepared and tested in the ring-opening polymerization reaction of tetrahydrofuran. The effects of the counter-cation (H+, NH4+) and the peripheral atoms (Mo, W) on the polymerization were investigated. It has been found that when the protons of H3PMo12O40·13H2O were replaced by the ammonium cations the polymerization rate decreased dramatically. Whereas, when the peripheral atoms (Mo) were replaced by their homologous (W), the polymerization rate increased twofold. As for the viscosity average molecular weight (My) of polymer products, it was found that the high molecular weight (7930) was obtained by using H3PW12O40·13H2O. The molecular weight (My) obtained by H3PMo12O40·13H2O and (NH4)H3PMo12O40·13H2O was 6470 and 6810, respectively. 展开更多
关键词 TETRAHYDROFURAN heteropoly compounds Ring opening polymerization Cyclic ether Solid acid
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Synthesis of Tungstophosphates of Heteropoly Compound and Its Catalytic Property in Oxidative Desulfurization of Diesel 被引量:1
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作者 BIN Xiaobei WANG Kaipeng +2 位作者 CAO Hong KUANG Shenglu YUAN Jizu 《Wuhan University Journal of Natural Sciences》 CAS 2008年第1期98-102,共5页
Several kinds of Tungstophosphates of Heteropoly Compounds (TPHC) with different compositions and the same structure were synthesized using the method of solid-phase reaction to change the tool ratio of Na4P2O7·... Several kinds of Tungstophosphates of Heteropoly Compounds (TPHC) with different compositions and the same structure were synthesized using the method of solid-phase reaction to change the tool ratio of Na4P2O7·10H2O, WO3 and Na2WO4 · 2H2O. TPHC, as a catalyst, was used in oxidative desulfurization of diesel. The results show that TPHC has catalytic activity. With THPC existing, the highest desulfurization rate reaches 51.85%, 32.6% higher than that yield without TPHC. And the desulfiarization rate increases with decreasing WO3. FT-IR spectra of TPHC shows that the catalytic activity is related to the activity of end oxygen(Od).The more active Od is, the stronger the capability of obtaining or losing electron is. It means that TPHC has a good catalytic activity. FT-IR spectra of TPHC indicates that desulfurization rate is in linear correlation with Iw-Od/Ip-Od/ Iw-Od is intensity of W-Od vibration band, Ip-Od is intensity of P-Od vibration band) and correlation coefficient reaches 0.965. 展开更多
关键词 DIESEL oxidative desulfurization heteropoly compound CATALYST
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Synthesis,X-ray Structure and Spectral Propertiesofa Tetra-component Heteropoly Compound
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作者 ZHANG Heng-bin , YANG Guang-di,QI Xing-yi and LI Shu-jia( Department of Chemistry, Jilin University, Changchun,130023) XU Shan-peng (Department of chemistry,Heilongjiang University, Harbin, 150080) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1994年第3期227-235,共9页
he single crystal of a tetra-component heteropoly compound Mo_2Co_3O_(68) (H_2O_2)_2 ] [MoO_6]. 15(H_2O) was obtained in an aqueous solution with Na_2MoO_4 , Na_2WO_4, Co (NO_3)_2 and H_3PO_4 as starting materia... he single crystal of a tetra-component heteropoly compound Mo_2Co_3O_(68) (H_2O_2)_2 ] [MoO_6]. 15(H_2O) was obtained in an aqueous solution with Na_2MoO_4 , Na_2WO_4, Co (NO_3)_2 and H_3PO_4 as starting materials. The erystallo-graphic data determined by means of X-ray diffraction analysis are: triclinic sys -tem,space group Pl ,Z= 2:a =1.9227(9) nm,b=1.9359(7)nm , c=1.2565(3)nm . a = 91. 43 (3), The Differential thermal and thermogravimetric analysis indicated the thermal stbility of the compound and its spectral properties were characterized by IR and XPS measurements . 展开更多
关键词 heteropoly compound P-W-Mo-Co system SYNTHESIS STRUCTURE
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Catalytic Oxidation of Hexanol to Hexanal with H_2O_2 Over P-W Heteropoly Compounds
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作者 ZHOU Guang-dong GUO Xiao-hong +2 位作者 LIU Yan BI Ying-li ZHEN Kai-ji 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2001年第3期293-298,共6页
The syntheses of Keggin and Dawson-structural phospho-tungsto heteropoly compounds and their Peroxo-derivatives(PCWP), and the catalytic performance over this series of catalysts for the selective oxidation of hexanol... The syntheses of Keggin and Dawson-structural phospho-tungsto heteropoly compounds and their Peroxo-derivatives(PCWP), and the catalytic performance over this series of catalysts for the selective oxidation of hexanol to hexylaldehyde are reported. By means of IR, NMR and UV-DRS techniques the catalysts were characterized and a comparison of the structural properties of these catalysts before and after the reaction was made. The correlation between the catalytic performance and the structure of this series of catalysts was discussed as well. 展开更多
关键词 P-W heteropoly compound HEXANOL HEXANAL
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SYNTHESIS OF ALLANTOIN USING HETEROPOLY COMPOUNDS AS CATALYSTS
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作者 Sui Mei ZHANG Feng Lian ZHAO Wei Qing WANG(Department of Chemical Engineering, Harbin Engineering University,Harbin, 150001) 《Chinese Chemical Letters》 SCIE CAS CSCD 1995年第4期337-338,共2页
Allantoin was synthesized with the yield as high as 68.5% using H3PW12O40. xH(2)O as catalyst. Optimum conditions for the synthesis were determined. It. was found that the heteropoly compound has higher catalytic acti... Allantoin was synthesized with the yield as high as 68.5% using H3PW12O40. xH(2)O as catalyst. Optimum conditions for the synthesis were determined. It. was found that the heteropoly compound has higher catalytic activity than conventional inorganic acid catalysts (such as hydrochloric acid, etc.) 展开更多
关键词 AS SYNTHESIS OF ALLANTOIN USING heteropoly compoundS AS CATALYSTS
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Anti-Influenza Virus Activity of Heteropoly Complexes Containing Rare Earth Elements
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作者 Liu, Jie Wang, Enbo +1 位作者 Peng, Jun Zhou, Yunshan 《Journal of Rare Earths》 SCIE EI CAS CSCD 1999年第2期60-63,共4页
AntiA3typeinfluenza virus activity and toxicity for chick embryo of some heteropoly compounds containing rare earth elements were investigated. The results demonstrate that these heteropoly compounds directly inactiva... AntiA3typeinfluenza virus activity and toxicity for chick embryo of some heteropoly compounds containing rare earth elements were investigated. The results demonstrate that these heteropoly compounds directly inactivate the A3type influenza virus, and the inhibition rate of K15)2]15H2O for the A3type influenza virus is more than 90% with antivirus index TI 69. The result is obviously superior to that of the positive reference drug ribavirin. 展开更多
关键词 Rare earths heteropoly compound Chick embryo experiment Influenza virus Antivirus activity
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Syntheses and Application of All-lithium Salts of Heteropolyacid as Electrolyte of Lithium-ion Battery
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作者 CHENYa-guang WANGCUn-guo ZHANGXi-yan XIEDe-min WANGRong-shum 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第1期77-80,共4页
The all-lithium salts of heteropoly acid Li_xXM_ 12O_ 40(HPA-Li)(X=P, Si; M=Mo, W) were obtained via ion exchange and characterized by means of IR and UV spectroscopies, TG and elemental analyses. The conductivity o... The all-lithium salts of heteropoly acid Li_xXM_ 12O_ 40(HPA-Li)(X=P, Si; M=Mo, W) were obtained via ion exchange and characterized by means of IR and UV spectroscopies, TG and elemental analyses. The conductivity of the electrolytic solution consisting of Li_3PW_ 12O_ 40 and PC/DME mixing solvent(1/2.5, volume ratio) is up to 7.2×10 -2 S/cm, being higher than that of LiClO_4 as the electrolyte. The all-lithium salts were used as electrolytes in secondary lithium-ion batteries. The discharge capacity of the PAS/Li batteries with Li_3PW_ 12O_ 40 electrolyte solutions reaches to 148 (mA·h)/g and the cyclic life is up to 380 times, much better than those of commercialized products with LiClO_4 and LiAsF_6 as electrolytes. 展开更多
关键词 All-lithium salt heteropoly compound ELECTROLYTE Lithium-ion secondary battery
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Hydrothermal Synthesis and Characterization of a Novel Organic Inorganic Hybrid Compound [Co(dien)_2](dienH_3)(H_3O)_7[P_2Mo_5O_(23)]_2·14H_2O
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作者 赵卫锋 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2007年第1期120-121,共2页
A new compound,[Co(dien)2](dienH3)(H3O)7[P2Mo5O23]2·14H2O, has been hydrothermallly synthesized by using Na2MoO4,CoCl2, H3PO4 and dien, and structurally characterized by elemental analysis, X-ray powder dif... A new compound,[Co(dien)2](dienH3)(H3O)7[P2Mo5O23]2·14H2O, has been hydrothermallly synthesized by using Na2MoO4,CoCl2, H3PO4 and dien, and structurally characterized by elemental analysis, X-ray powder diffraction analysis, SEM, IR and TG analysis. The results show that the compound is composed of a polyanion [P2Mo5O23]2^12, complex [Co(dien)2]^2+ cation, protonated [dienH3]^3+ , and forteen crystallization water molecule. 展开更多
关键词 hydrotherrnal synthesis heteropoly compound organic-inorganic hybrid compound
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Characterization of Titanium-Containing Compounds in Gray Iron
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作者 曾大新 张元好 +2 位作者 刘建勇 何汉军 洪晓先 《Tsinghua Science and Technology》 SCIE EI CAS 2008年第2期127-131,共5页
Titanium produces different compounds in gray iron. In order to determine their characteristics, a scanning electron microscope, an energy dispersive X-ray spectroscopy, and an optical microscopy were used to analyze ... Titanium produces different compounds in gray iron. In order to determine their characteristics, a scanning electron microscope, an energy dispersive X-ray spectroscopy, and an optical microscopy were used to analyze the morphology, distribution, and composition of titanium-containing compounds in metal- Iographic specimens and machined surfaces in four gray irons. The results show that the titanium-containing compounds in the gray irons are complex compounds containing V, Nb, Mn, S, and other metals, depending on the concentration of these elements in the iron. The number of titanium-containing compounds increases with increasing Ti content in the gray iron. Most of the titanium-containing compounds are located in the pearlite matrix, with some in the steadite and carbides. The results suggest that titanium-containing compounds reduce tool lifetime. 展开更多
关键词 gray iron titanium-containing compound COMPOSITION distribution MACHINING
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杂多酸催化剂及其在精细化学品合成中的应用 被引量:66
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作者 赵忠奎 李宗石 +2 位作者 王桂茹 乔卫红 程侣伯 《化学进展》 SCIE CAS CSCD 2004年第4期620-630,共11页
详细介绍了环境友好的杂多化合物的结构、性能、制备、表征及其在精细化学品合成中的应用最新进展 ,并对负载型杂多酸和新颖的混合型杂多酸及其盐催化剂的合成及应用进行综述。认为杂多化合物的深入研究具有十分重要的理论价值和现实意... 详细介绍了环境友好的杂多化合物的结构、性能、制备、表征及其在精细化学品合成中的应用最新进展 ,并对负载型杂多酸和新颖的混合型杂多酸及其盐催化剂的合成及应用进行综述。认为杂多化合物的深入研究具有十分重要的理论价值和现实意义。杂多酸及盐作为绿色催化剂在精细化学品合成中具有广阔的应用前景。 展开更多
关键词 杂多化合物 精细化学品 负载杂多酸 新型混和杂多酸 绿色催化剂
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双-11钨钛希土三元杂多化合物的合成与性质研究 被引量:13
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作者 王炜 刘景福 王恩波 《无机化学学报》 SCIE CAS CSCD 北大核心 1991年第2期160-164,共5页
本文报道了双-11钨钛希土三元杂多化合物K_(13)[Ln(TiW_(11)O_(39))_2]·xH_2O(Ln=La,Ce,Pr,NdSm,Eu,Gd,Tb,Dy,Ho,Er,Yb,Y,Ce(Ⅳ))的合成方法,溶液性质,红外光谱,紫外光谱,X光电子能谱,热分析等的研究结果.
关键词 杂多化合物 稀土
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具有Keggin结构的多元杂多化合物的合成与光谱研究Ⅱ 被引量:5
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作者 林志华 张汉辉 +2 位作者 郭春华 黄长沧 孙瑞卿 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2002年第5期752-754,共3页
本文合成了一些具有Keggin结构的Si V Mo W四元杂多阴离子 [SiVxMoyW12 x yO4 0 ]( 4+x) -的化合物 (其中 ,x =1,2和 3) ,并对其进行了红外光谱研究 ,可看到化合物的M =Od,M Ob M和M Oc M的红外伸缩振动峰随着V原子数目的增加而红移 ;... 本文合成了一些具有Keggin结构的Si V Mo W四元杂多阴离子 [SiVxMoyW12 x yO4 0 ]( 4+x) -的化合物 (其中 ,x =1,2和 3) ,并对其进行了红外光谱研究 ,可看到化合物的M =Od,M Ob M和M Oc M的红外伸缩振动峰随着V原子数目的增加而红移 ;而钨原子数目的增加一般使之蓝移 ,因此推测出杂多化合物的酸性随着V数目的增加而减弱 ,氧化反应性能则相反。这种变化规律与 [PVxMoyW12 -x -yO4 0 ]( 3 +x) -相似。另外 ,可看到P系列的多元杂多酸 (或杂多化合物 ) 展开更多
关键词 多元杂多化合物 合成 KEGGIN结构 红外光谱 构效关系 催化性能 分子结构
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锰为中心原子的三元杂多配合物的合成与氧化还原性质研究 被引量:15
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作者 曹晶晶 周百斌 +2 位作者 马慧媛 徐学勤 韦永德 《分子科学学报》 CAS CSCD 2004年第2期41-47,共7页
 用直接法合成了以锰为中心原子的过渡元素和钨的三元杂多配合物,经ICP和TG曲线确定其化学式为K5,6[MnM(OH2)W11O39]·xH2O(M=Mn2+,Fe3+,Co2+,Ni2+,Cu2+,Zn2+和Cd2+),采用IR,UV,XRD和XPS等手段对配合物结构进行了表征,用循环伏安...  用直接法合成了以锰为中心原子的过渡元素和钨的三元杂多配合物,经ICP和TG曲线确定其化学式为K5,6[MnM(OH2)W11O39]·xH2O(M=Mn2+,Fe3+,Co2+,Ni2+,Cu2+,Zn2+和Cd2+),采用IR,UV,XRD和XPS等手段对配合物结构进行了表征,用循环伏安测定了其系列配合物的氧化还原性质,得出系列配合物的氧化性顺序,同时讨论配合物的热稳定性. 展开更多
关键词 中心原子 三元杂多配合物 合成 氧化还原性 直接法 热稳定性 过渡元素
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杂多化合物及其负载型催化剂的研究进展 被引量:12
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作者 周广栋 甄开吉 +1 位作者 王海水 程铁欣 《化学进展》 SCIE CAS CSCD 北大核心 2006年第4期382-388,共7页
详细介绍了杂多化合物及其负载型催化剂的研究进展并对不同的催化剂载体进行了总结。对杂多化合物与载体之间的相互作用以及杂多化合物催化剂的反应机理进行了讨论。
关键词 杂多化合物 负载 催化
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十一钨锌杂多配合物位置异构体的合成、表征及催化性能 被引量:14
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作者 马荣华 刘春涛 瞿伦玉 《无机化学学报》 SCIE CAS CSCD 北大核心 2000年第4期688-692,共5页
The four heteropoly isomers K3H3[α ,β i SiW11Zn(H2O)O39]· XH2O(β i=β 1,β 2,β 3) were prepared and characterized by elementary analysis, IR and UV spectroscopy, polargraphy and cyclic voitammetry, 183W NMR a... The four heteropoly isomers K3H3[α ,β i SiW11Zn(H2O)O39]· XH2O(β i=β 1,β 2,β 3) were prepared and characterized by elementary analysis, IR and UV spectroscopy, polargraphy and cyclic voitammetry, 183W NMR and XPS experiments. And these compounds can catalyze epoxidation reaction of olefine. 展开更多
关键词 十一钨锌杂多酸盐 异构体 催化活性 合成 催化剂
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实现NO_x吸附分解的杂多化合物催化新体系研究 被引量:7
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作者 王睿 吴丹 +2 位作者 赵大传 于慧 赵海霞 《现代化工》 CAS CSCD 北大核心 2006年第z2期120-123,125,共5页
采用浸渍法、溶胶-凝胶法等不同途径制备了几种具有吸附分解NOx功能的多酸催化新体系,对其进行了IR、XRD表征,在固定床催化反应器中考察了体系对NOx的吸附与分解性能.结果表明:磷钨酸与SiO2之间有较强的相互作用,催化剂的分散形态与负... 采用浸渍法、溶胶-凝胶法等不同途径制备了几种具有吸附分解NOx功能的多酸催化新体系,对其进行了IR、XRD表征,在固定床催化反应器中考察了体系对NOx的吸附与分解性能.结果表明:磷钨酸与SiO2之间有较强的相互作用,催化剂的分散形态与负载量密切相关;负载型催化剂对NO2均有较好的吸附能力,其中Fe(Ⅲ)USY载体对体系有明显的增效作用;不同方法制备的负载型磷钨酸对NO2的吸附性能相近;钨系杂多化合物性能优于钼系,Keggin结构的活性优于Dawson结构;磷钨酸与磷钼酸具有复配增效作用;随着磷钨酸负载量的增加,体系对NO2的吸附能力显著提高,最高吸附率达90%;适宜的吸附温度和气速分别为180~200℃和0.1~0.2L/min.通过IR分析揭示了吸附质与催化剂的作用方式,通过GC-MS检测确认了吸附质催化分解为N2的有效性. 展开更多
关键词 杂多化合物 氮氧化物 吸附 分解
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异丁烯制备甲基丙烯醛催化剂的研究进展 被引量:11
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作者 李强 王蕾 +2 位作者 闫瑞一 李增喜 张锁江 《化学工业与工程》 CAS 2007年第5期433-438,共6页
异丁烯选择氧化制备甲基丙烯醛是异丁烯法制备甲基丙烯酸甲酯的关键步骤。本文综述了异丁烯选择氧化生成甲基丙烯醛催化剂,其中包括复合氧化物催化剂和杂多化合物催化剂等的研究现状,讨论了在Mo-Bi催化剂上异丁烯选择氧化生成甲基丙烯... 异丁烯选择氧化制备甲基丙烯醛是异丁烯法制备甲基丙烯酸甲酯的关键步骤。本文综述了异丁烯选择氧化生成甲基丙烯醛催化剂,其中包括复合氧化物催化剂和杂多化合物催化剂等的研究现状,讨论了在Mo-Bi催化剂上异丁烯选择氧化生成甲基丙烯醛的反应机理。 展开更多
关键词 甲基丙烯醛 异丁烯 选择氧化 复合氧化物 杂多化合物
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钨钛磷稀土杂多酸盐的合成及其抗艾滋病病毒活性的研究 被引量:20
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作者 刘术侠 王力 +3 位作者 刘彦勇 王恩波 曾毅 李泽淋 《中国稀土学报》 CAS CSCD 北大核心 1997年第1期59-63,共5页
合成了通式为LnxH[PTi2W10O40]·xH2O(Ln=La、Ce、Pr、Nd、Sm、Eu、Gd、Tb、Yb、Lu)的稀土杂多配合物,通过IR、UV、31P、183WNMR谱对其结构进行了表征。配合物抗艾滋... 合成了通式为LnxH[PTi2W10O40]·xH2O(Ln=La、Ce、Pr、Nd、Sm、Eu、Gd、Tb、Yb、Lu)的稀土杂多配合物,通过IR、UV、31P、183WNMR谱对其结构进行了表征。配合物抗艾滋病病毒(HIV1)活性的研究表明。 展开更多
关键词 钨钛磷杂多酸 抗艾滋病病毒 活性 稀土元素
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杂多化合物的合成与结构性能研究的近代发展 被引量:24
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作者 高孝恢 肖慎修 +1 位作者 陈天朗 蒋淑芬 《化学研究与应用》 CAS CSCD 1999年第4期350-357,共8页
本文对含有各种新组分的新合成的杂多化合物物种进行了综述,并概述了Keggin型阴离子的酸性、氧化性和稳定性的一些规律性与结构的关系问题。
关键词 合成 结构与性质 杂多化合物 综述
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一些含钒杂多化合物的合成、表征及其在环己烷催化氧化反应中性能的研究 被引量:7
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作者 井淑波 朱万春 +2 位作者 管景奇 王振旅 王国甲 《化学学报》 SCIE CAS CSCD 北大核心 2006年第18期1881-1884,共4页
合成了一系列钒取代在不同位置的杂多化合物,考察了它们在环己烷催化氧化反应中的活性及其过氧化氢的分解情况,发现钒的配位环境是影响反应活性的重要因素.其中以H4PMo11VO40为代表的钒在配位原子位置上的磷钼钒酸,不但显示了很好的催... 合成了一系列钒取代在不同位置的杂多化合物,考察了它们在环己烷催化氧化反应中的活性及其过氧化氢的分解情况,发现钒的配位环境是影响反应活性的重要因素.其中以H4PMo11VO40为代表的钒在配位原子位置上的磷钼钒酸,不但显示了很好的催化环己烷氧化反应的活性,而且H2O2的分解反应同时也得到了较好的抑制. 展开更多
关键词 含钒杂多化合物 环己烷 氧化反应
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