检索结果-南通市图书馆

Chemical Research in Chinese Universities 1996年第1期12卷 70-80页

作者： CHEN Ping ZHANG Hong-bin LIN Guo-dong and tsai khi-rui (department of chemistry &. state key laboratory for physical chemistry of the solid surface, xiamen university, xiamen, 361.05) xiamen UNIV DEPT CHEMXIAMEN 361005PEOPLES R CHINA xiamen UNIV STATE KEY LAB PHYS CHEM SOLID SURFACEXIAMEN 361005PEOPLES R CHINA

Highly active and selective Ni-based catalysts for partial oxidation of methane (POM) to syngas (CO/H,) have been studied and developed. Spectroscopic characterization by XRD, XPS, EPR, etc. demonstrated that under the POM reaction conditions, the Ni-components of the catalysts investigated were reduced and enriched on the surface to form metallic Ni0-phase. A comparative study of the first series of transition-metals showed that only Ni and Co have a high POM activity and selectivity, whereas the others (including Mn, Fe, Cu, etc. ) give mainly complete combustion products, Co, and H2O. The results favor the following viewpoints: the PoM activity is related with the rapidly changeable valence transitionmetal sites, M0/M2+ (e. g. Ni0/Ni2+ ), on the surface of the functioning catalysts;the transition-metal sites in zero-valence state seem to be responsible for the activation and dehydrogenation of methane by homolytic splitting of its C-H bonds on these sites. and the nature of rapidly changeable valence of the active sties is requisite for activation and rapid conversion of dioxygen.

关键词： Partial oxidation of methane Syngas Ni-based catalysts

Studies of Catalysis in Partial Oxidation of Methane to Syngas（Ⅱ）──Chemisorbed Species，Energetics and Mechanism

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 1995年第4期11卷 323-335页

作者： CHEN Ping ZHANG Hong-bin LIN Guo-dong andtsai khi-rui(department of chemistry &state key laboratory for physical Chemistyry of the solid surface ,xiamen university ,xiamen 361.05) xiamen UNIV DEPT CHEMXIAMEN 361005PEOPLES R CHINA xiamen UNIV STATE KEY LAB PHYS CHEM SOLID SURFACEXIAMEN 361005PEOPLES R CHINA

he characteristic study,by means of in-situ IR spectroscopy, of chemisorbed species on the Ni-catalysts for the partial oxidation of methane(POM)to syngas demonstrated the existence of CH_x(a)and H_xCO(a)adspecies on the functioning Ni-catalysts, Several designed experimental investigations on the reactivities of methane with CO_2 and with O_2,respectively,over the Ni-catalysts, and of CO_2 with the prereduced Ni-catalyst,ats well as of the deposited carbon with CO_2 and with O_2,respectlvely,liave been carried out and the reLqults were unfavorable to the two-step mechanistic interpretation proposed for the POM reaction. By means of tlie BOC-MP Approach,energetics of a set of elementary reactions,which may be involved in the POM process,on the clean(111)surface of Ni,Fe,Cu and Pd, re- spectively,has been *** result;of the experiments and the calculation of the present work favor the direct catalytic dissociation-plus-surface oxidation-plus-further debdrogenation mechanism as the dominant pathway making major contribution to the POM reaction.

关键词： Partial oxidation of methane Syngas Chemisorbed species Energetics. Mechanism

The　Active　Oxygen　Species　for　Oxidative　Coupling　of　Methane　over　CeO_2/BaF_2　Catalyst　by　in　Situ　Confocal　Microprobe　Raman　Spectroscopy

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 1997年第1期13卷 93-95页

作者： LONG rui qiang and WAN Hui lin (department of chemistry and state key laboratory for physical chemistry of the solid surface, xiamen university, xiamen, 361.05) xiamen UNIV DEPT CHEMXIAMEN 361005PEOPLES R CHINA xiamen UNIV STATE KEY LAB PHYS CHEM SOLID SURFACEXIAMEN 361005PEOPLES R CHINA

ＴｈｅＡｃｔｉｖｅＯｘｙｇｅｎＳｐｅｃｉｅｓｆｏｒＯｘｉｄａｔｉｖｅＣｏｕｐｌｉｎｇｏｆＭｅｔｈａｎｅｏｖｅｒＣｅＯ２／ＢａＦ２ＣａｔａｌｙｓｔｂｙｉｎＳｉｔｕＣｏｎｆｏｃａｌＭｉｃｒｏｐｒｏｂｅＲａｍａｎＳｐｅｃｔ... 详细信息

ＴｈｅＡｃｔｉｖｅＯｘｙｇｅｎＳｐｅｃｉｅｓｆｏｒＯｘｉｄａｔｉｖｅＣｏｕｐｌｉｎｇｏｆＭｅｔｈａｎｅｏｖｅｒＣｅＯ２／ＢａＦ２ＣａｔａｌｙｓｔｂｙｉｎＳｉｔｕＣｏｎｆｏｃａｌＭｉｃｒｏｐｒｏｂｅＲａｍａｎＳｐｅｃｔｒｏｓｃｏｐｙ＊＊Ｓｕｐｐｏｒｔｅ...

关键词： Oxygen species Oxidative coupling Methane In situ Raman spectroscopy

SYNTHESIS OF POLYCATECHOL WITH ELECTROCHEMICAL ACTIVITY AND ITS PROPERTIES

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2002年第6期20卷 517-524页

作者： Yong Kong Shao-lin Mu Bing-wei Mao department of chemistry School of Sciences, Yangzhou university Yangzhou 225002, China state key laboratory of physical chemistry of the solid surface, xiamen university,xiamen 361.05, China Yangzhou Univ Sch Sci Dept Chem Yangzhou 225002 Peoples R China xiamen Univ State Key Lab Phys Chem Solid Surface Xiamen 361005 Peoples R China

The electrochemical polymerization of catechol on platinum has been carried out using repeated potential cycling between -0.2 and 1.1 V (versus SCE). The electrolytic solution consisted of 0.2 mol dm(-3) catechol, 0.5 mol dm(-3) NaCl and 0.1 mol dm(-3) Na2HPO4 with pH 8.72. Catechol can not be polymerized at pH greater than or equal to 10.12. Polycatechol has an electrochemical lactivity at pH less than or equal to 4. The anodic and cathodic peak potentials of polycatechol shift towards more negative values as the pH of the solution increases from 1 to 4. The electrochemical activity of polycatechol hardly changes in this pH region, but it decreases slowly with time. This is caused by oxygen in air, which leads to an irreversible oxidation of polycatechol. This property is favorable for protecting metals from corrosion. Raman and FTIR spectra of polycatechol and catechol are quite different. AFM images of polycatechol films provide evidence that the image of the oxidized state of polycatechol is markedly different from that of the reduced one. This difference is caused by doping and dedoping of polycatechol.

关键词： catechol polycatechol electrochemical activity Raman spectra FTIR spectra AFM images

PERFORMANCE　AND　CHARACTERIZATION　OF　NOVEL　ELECTROCATALYST　FOR　OXYGEN　REDUCTION

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 1995年第9期6卷 807-810页

作者： YongYANG Jin Kua YOU Zu Geng LIN(state key laboratory for physical chemistry or the solid surface and department of chemistry, xiamen university, xiamen, 361.05) xiamen Univ Dept Chem Xiamen 361005 Peoples R China xiamen Univ State Key Lab Phys Chem Solid Surface Xiamen 361005 Peoples R China

Abstract: The preparation and characterization of novel electrocatalyst for oxygen reduction have been carried out. It is found that heated Fe-PPy/C catalysts show good catalytic activity f'or oxygen reduction in alkaline or acid solutions. Direct correlation between ESR signal and catalytic activity of the catalysts has been obtained. Some implications from this catalytic system have also been discussed.

关键词：

ASSIGNMENTS FOR THE GROUND stateS OF METAL MONOCARBONYLS

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 1995年第10期6卷 887-890页

作者： Xin XU Nan Qin WANG Xin LU Qian Er ZHANG(state key laboratory for physical chemistry of the solid surface,department of chemistry,xiamen university,fujian 361.05) xiamen Univ Dept Chem State Key Lab Phys Chem Solid Surface Xiamen 361005 Peoples R China

The bonding mechanisms between the first-row transition metal and carbon monoxide were discussed. Three basic rules have been drawn up to determine the ground states of the metal monocarbonyls. The theoretical assignm...

关键词：

STUDIES ON BaF2 PROMOTED PRASEODYMIUM OXIDE CATALYSIS FOR THE OXIDATIVE COUPLING OF METHANE

在线全文

学校读者我要写书评

暂无评论

Journal of Energy chemistry 1997年第2期 85-92页

作者： LONG rui-Qiang WAN Hui-Lin(department of chemistry and state key laboratory for physical chemistry of the solid surface xiamen university xiamen, fujian 361.05)

The catalytic performance for oxidative coupling of methane (OCM) and characterizations of the BaF2 promoted praseodymium oxide catalysts have been studied in this work. The results showed that C2 selectivities and yields over the BaF2 promoted Pr6O11 catalysts were significantly higher than those over Pr6O11 catalyst. In the process of catalyst preparation, the partial exchange between F- and O2- led to the formation of PrOF new phase and the contraction of BaF2 lattice. The increase in C2 selectivity over BaF2 doped Pr6O11 might result from the decrease of specific surface area and mobility of lattice oxygen as well as the dispersion of F- on the surface of the catalysts. No direct relationship between the surface acidity/basicity and the catalytic activity/selectivity was observed over these catalysts.

关键词： methane oxidative coupling praseodymium chide BaF2

Study　of　Binary　Rare－Earth　Oxyfluoride　for　ODE　Reaction　and　Their　XRD　＆In－Situ　Raman　Characterization

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 1996年第10期7卷 954-955页

作者： Ji Zhong LUO Xiao Ping ZHOU Zi Sheng CHAO Hu Lin WAN(department of chemistry & state key laboratory for physical chemistry of the solid surface,xiamen university, xiamen 361.05) xiamen UNIV DEPT CHEMXIAMEN 361005PEOPLES R CHINA xiamen UNIV STATE KEY LAB PHYS CHEM SOLID SURFACEXIAMEN 361005PEOPLES R CHINA

A series of new binary rare earth oxyfluoride (Sm2O3-LaF3) catalysts have been developed for ODE reaction. High C2H4 selectivity(91.5%) with C2H6 conversion 21.7% was achieved on the catalyst Sm2O3/LaF3 with molar ratio 1/1 at 700℃. The addition of 16.7 mol% BaF2 into Sm2O3/LaF3(1/1 in mol) led to the increase of C2H6 conversion from 21.7% to 40.8%,however. the change of ethene seletivity was not apparent (from 91.5% to 88.0%).

关键词： ODE Reaction Oxyfluoride Their XRD

Preparation and Characterization of Gold Thin Film Electrode Modified by Microbe

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 1999年第4期10卷 311-312页

作者： Jin Kun FU Rong Zong HU Wei De ZHANG Xin Sheng YU Jin Yin FU(state key laboratory for physical chemistry of solid surface, department of chemistry and Institute of physical chemistry, xiamen university, xiamen 361.05) xiamen Univ Dept Chem State Key Lab Phys Chem Solid Surface Xiamen 361005 Peoples R China xiamen Univ Inst Phys Chem Xiamen 361005 Peoples R China

A novel method based on microbe modification has been employed to prepare gold thin film electrode. The preparation method is simple and the electrode obtained is stable and very sensitive in determining heavy metal i... 详细信息

关键词： gold thin film electrode microbe modification trace analysis

Electrocatalytic Oxidation of Hypophosphite on Nickel Electrode ──In Situ UV-Vis Spectroscopic study

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 1999年第10期10卷 863-866页

作者： Yue ZENG Shao Min ZHOU ( department of chemistry. Hunan Normal university, Changsha 410006 state key laboratory for physical chemistry of the solid surface.department of chemistry. xiamen university, xiamen 361.05) Hunan Normal Univ Dept Chem Changsha 410006 Peoples R China xiamen Univ Dept Chem State Key Lab Phys Chem Solid Surface Xiamen 361005 Peoples R China

The electrocatalytic oxidation of hypophosphite on a nickel electrode has been studiedby means of in site UV-Vis subtractive reflectance spectroscopy. An absorbency band around 245um . which was ascribed to the formation of an intermediate, PHO2-, was observed in theelectrocatalytic oxidation process. Accordingly, the electrocatalytic oxidation of hypophosphitemight undergo a H abstraction of hypophosphite from the P-H bond to form the phosphoruscentred radical PHO2-, which is subsequently electrooxidized to the final product, phosphite.

关键词： In situ UV-Vis subtractive reflectance spectroscopy electrooxidation hypophosphite mechanism.