检索结果-南通市图书馆

纳米SiO_2负载Preyssler杂多酸催化剂对水杨酸与苄醇或脂肪醇酯化反应的催化性能(英文)

在线全文

学校读者我要写书评

暂无评论

催化学报 2011年第5期32卷 782-788页

作者： fatemeh f. bamoharram Majid M. HERAVI Javad EBRAHIMI Ali AHMADPOUR Mojtaba ZEBARJAD Department of.Chemtstry Islamic Azad University Mashhad Branch Mashhad Iran Department of.Chemistry School of Sciences Alzahra University Tehran Iran Deptartment of.Chemical Engineering Faculty of Engineering Ferdowsi University of Mashhad Mashhad 1ran Department of.Materials Science and Engineering Faculty of Engineering Ferdowsi University of Mashhad Mashhad Iran

An ef.icient and environmentally benign procedure f.r the catalytic esterif.cation of.salicylic acid with aliphatic alcohols, CnH2n+1OH(n=1-5)and benzylic alcohols,RC6H4CH2OH(R=H,NO2,OCH3,Br,Cl,Me)was developed using nano-SiO2-supported Preyssler heteropolyacid both under thermal conditions and microwave *** nanostructures were obtained through a sol-gel method and were characterized by transmission electron microscopy and powder X-ray *** ef.ects of.various parameters such as solvent type,molar ratio of.substrates,Preyssler heteropolyacid loading on silica,catalyst amount,temperature,and reaction time were studied and the optimum conditions were *** has been f.und that the catalyst with 30 wt%loading is highly active and shows high yields in esterif.cation *** use of.nano-SiO2-supported Preyssler heteropolyacid coupled with microwave irradiation allows a solvent-f.ee,rapid(3 min),and high-yielding *** catalyst can be easily recovered and reused f.r many times without a signif.cant loss in its activity.

关键词： Preyssler heteropolyacid silica esterif.cation salicylic acid

Photocatalytic Synthesis of.Gold Nanoparticles Using Preyssler Acid and Their Photocatalytic Activity

在线全文

学校读者我要写书评

暂无评论

催化学报 2011年第6期32卷 978-982页

作者： Ali AYATI Ali AHMADPOUR fatemeh f.bamoharram Majid M.HERAVI Hamed RASHIDI Department of.Chemical Engineering Ferdowsi University of Mashhad Department of.Chemistry School of SciencesIslamic Azad University Department of.Chemistry School of SciencesAlzahra University

Preyssler acid H14[NaP5W30O110] was used as reducing agent and stabilizer f.r the synthesis of.gold nanoparticles by photolysis of.Au(III)/Preyssler acid/propan-2-ol *** acid plays both the role of.transf.rring electrons f.om propan-2-ol to Au(III) and stabilizing the ***-2-ol was used as sacrif.cial reagent f.r the photof.rmation of.reduced Preyssler *** nanoparticles (Au NPs) were characterized by UV-Vis spectroscopy,transmission electron microscopy (TEM),and particle size distribution (PSD) *** synthesized Au NPs had a unif.rm hexagonal morphology and their size was about 17 *** catalytic perf.rmance of.these NPs f.r photodegradation of.methyl orange (MeO) was investigated in aqueous ***-Vis studies showed that Au NPs can catalyze photodegradation of.this azo *** pseudo-f.rst-order rate constants were also calculated f.r this reaction.

关键词：固体超强碱氧化钙硝酸钾氧化铝氧化锆氢氧化钾硝酸钙

A kinetic study of.the electron-transf.r in the reaction of.tribenzylchlorotin with[CoW_(12)O_(40)]^(5-)

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2009年第8期20卷 1005-1009页

作者： fatemeh f.bamoharram Mohammad M.Heravi Touran Ardalan Pouran Ardalan Department of.Chemistry Islamic Azad UniversityMashhad BranchMashhadIran Young Researchers Club Islamic Azad UniversityMashhad BranchMashhadIran

A kinetic study of.the electron-transf.r in the reaction of.tribenzylchlorotin with potassium 12-tungsto cobalt （Ⅲ） ate ion, Ks[CoW12O40], abbreviated as Co（III）W, has been perf.rmed in dif.erent solvents. The studies were carried out in methanol, ethanol, acetonitrile and acetic acid/water. The rate constants, reaction rates and activation parameters were calculated. Our f.ndings show that the rate of.disappearance of.the Co（Ⅲ） is pseudo-f.rst order. The kinetic data is strongly af.ected by used solvents. The maximum and minimum rate constants were achieved in the ethanol and acetic acid/water （70/30） as a solvent, respectively. In all of.the used solvents, negative value of.activation entropies was observed, but negative activation enthalpies are observed in methanol, ethanol and acetonitrile. The reaction rate is increased with increase of.Co（Ⅲ） concentration. ？2009 fatemeh E bamoharram. Published by Elsevier B.V. on behalf.of.Chinese Chemical Society. All rights reserved.

关键词： Kinetic study Potassium 12-tungsto cobalt (III) ate ion Pseudo-f.rst order Keggin

Synthesis of.3-(aryl)-2-thioxo-2,3-dihydroquinazolin-4(1H)-one derivatives using heteropolyacids as green,heterogeneous and recyclable catalysts

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2011年第2期22卷 131-134页

作者： S.Allameh M.M.Heravi M.M.Hashemi f.f.bamoharram Department of.Chemistry Science and Research BranchIslamic Azad UniversityTehranIran Department of.Chemistry School of SciencesAlzahra UniversityVanakTehranIran Department of.Chemistry Faculty of SciencesIslamic Azad UniversityMashhad BranchMashhadIran

Reaction of.isatoic anhydride with aniline derivatives gave 2-amino-N-（aryl）*** latters reacted with phenyli-sothiocyanate in the presence of.heteropolyacids in various solvents which af.orded 3-（aryl）-2-thioxo-2,3-dihydroquinazolin- 4（1H）-one *** ef.ects of.various heteropolyacids including Preyssler and Keggin on the yields and reaction times have been investigated.

关键词： Thioxo-quinazolinones Recyclable catalysts Heteropolyacids Heterogeneous

二氧化硅担载Preyssler杂多酸上苯和1-癸烯的烷基化反应：利用表面响应方法进行统计设计(英文)

在线全文

学校读者我要写书评

暂无评论

催化学报 2012年第3期33卷 494-501页

作者： A. HAf.ZI A. AHMADPOUP M. M. HERAVI f. f. bamoharram M. KHOSROSHAHI Department of.Chemical Engineering Faculty of Engineering Ferdowsi University of Mashhad Mashhad *** Iran Department of.Chemistry School of Sciences Alzahra University Tehran *** Iran Department of.Chemistry Mashhad Branch-Islamic Azad University Mashhad *** Iran

The response surf.ce method (RSM) was applied to study the liquid phase alkylation of.benzene with 1-decene catalyzed by means of.silica supported Preyssler heteropoly acid. A three step experimental design was developed based on the central composite design (CCD). Catalyst loading, catalyst mass percent, and benzene to 1-decene molar ratio were used to optimize 1-decene conversion and linear alkylbenzene (LAB) yield. The results indicated that the quadratic model was signif.cant f.r these two responses. The experimental results revealed that all variables had positive ef.ect on 1-decene conversion. While increasing the catalyst loading tends to decrease LAB yield. Benzene to 1-decene molar ratio was f.und to be the most important f.ctor that inf.uenced LAB yield with a positive ef.ect. Design expert sof.ware suggested several optimized solutions, among them the best choice was to use 31% catalyst loading, benzene to 1-decene molar ratio of.13, and catalyst percent of.3.6 wt% f.r obtaining 100% conversion and 88% LAB production yield.

关键词：直链烷基苯烷基化反应统计设计杂多酸癸烯响应面法催化剂用量硅胶