原子团簇V_nP_m~+的几何结构与电子性质研究

对激光等离子体反应生成原子团簇ＶｎＰｍ＋进行了量子化学从头算研究，对可能的几何结构进行了试探性计算，并对其中较稳定构型进行了几何优化。结果表明，ＶＰｍ＋中，Ｖ倾向与双磷成键形成平面结构，其中ＶＰ＋４、ＶＰ６＋较稳定。二钒磷化物形成一个生长螺线，从Ｖ２Ｐ４＋至Ｖ２Ｐ８＋，双钒之间间隔的磷原子组成准四面体、五边形、六面体…，多钒磷化物中ＶａＰｂ＋与ＶａＰｂ＋具有相同几何构型，其中Ｖ３Ｐ３＋、Ｖ４Ｐ４＋为三钒、四钒磷化物中最稳定的构型

Interfacial Activation of Catalytically Inert Au (6.7 nm)-Fe3O4 Dumbbell Nanoparticles for CO Oxidation

通讯作者地址: Zheng, NF (通讯作者), Xiamen Univ, Coll Chem & Chem Engn, State Key Lab Phys Chem Solid Surfaces, Xiamen 361005, Peoples R China 地址: 1. Xiamen Univ, Coll Chem & Chem Engn, State Key Lab Phys Chem Solid Surfaces, Xiamen 361005, Peoples R China 2. Xiamen Univ, Coll Chem & Chem Engn, Dept Chem, Xiamen 361005, Peoples R China 电子邮件地址: [email protected] nanoparticles epitaxially grown on Fe3O4 in Au (6.7 nm)-Fe3O4 dumbbell nanoparticles exhibit excellent stability against sintering, but display negligible catalytic activity in CO oxidation. Starting from various supported Au (6.7 nm)-Fe3O4 catalysts prepared by the colloidal deposition method, we have unambiguously identified the significance of the Au-TiO2 interface in CO oxidation, without any possible size effect of Au. In situ thermal decomposition of TiO2 precursors on Au-Fe3O4 was found to be an effective way to increase the Au-TiO2 interface and thereby optimize the catalytic performance of TiO2-supported Au-Fe3O4 dumbbell nanoparticles. By reducing the size of Fe3O4 from 15.2 to 4.9 nm, the Au-TiO2 contact was further increased so that the resulting TiO2-supported Au (6.7 nm)-Fe3O4 (4.9 nm) dumbbell particles become highly efficient catalysts for CO oxidation at room temperature.National Natural Science Foundation of China 20871100 20721001 Distinguished Young Investigator Grant 20925103 Research Fund for the Doctoral Program of Higher Education of China 200803841010 Natural Science Foundation of Fujian 2009J06005 Key Scientific Project of Fujian Province 2009HZ0002-

Desorption Electrospray Ionization Mass Spectrometry for Monitoring the Kinetics of Baeyer-Villiger Solid-State Organic Reactions

Desorption electrospray ionization mass spectrometry (DESI-MS) has been used for monitoring solid-state organic reaction in ambient air, specifically the Baeyer-Villiger (BV) type reaction involving the oxidation of ketones (benzophenone or deoxybenzoin) by m-chloroperbenzoic acid (m-CPBA) in solid-state. The DESI mass spectra obtained at regular intervals during the BV reaction processes are featured, with the amount of ester products increasing as those of ketone reactants decrease. Quantitative analyses of relative intensities of the product, made to quantify the reaction degree of typical solid-state organic reaction (SSOR), show a precision with RSDs of around 5% to 12%, though the RSDs for direct analysis of intensities of the reactant or the product in the solid-state are obviously larger. The kinetics of the Baeyer-Villiger type reactions in solid-state are shown to be dramatically different, in reaction rate, kinetic curve, as well as concentration dependence, from those of the same reactions taking place in solution.NSFC,20525103,20721001 National Basic Research Program of China (973 Program)2007CB81530

Probing Hydrogen Bond Energies by Mass Spectrometry

E-mail Addresses: [email protected]; [email protected] spectrometry with desorption electrospray ionization (DESI) is demonstrated to be useful for probing the strength of hydrogen bonding, exemplified by various complexes of benzothiazoles and carboxylic acids in the solid state. Efficiencies for fragmentation of the complexes, quantified by collision-induced dissociation (CID) technology, correspond well with energies of the hydrogen bonds of O-H center dot center dot center dot N and N-H center dot center dot center dot O bridging each pair of benzothiazole and carboxylic acid. Linear correlations (with correlation factors of 0.8953 and 0.9928) have been established for the calibration curves of normalized collision energy at 100% fragmentation rate vs the length between donor and acceptor (in the hydrogen bond of O-H center dot center dot center dot N) as well as the slope of the fragmentation efficiency curve vs the average length difference between O-H center dot center dot center dot N and N-H center dot center dot center dot O in the complex. The mechanism responsible for determination of the hydrogen bonds is proposed on the basis of the experiments starting from the mixtures of the complexes as well as labeling with deuterium. As a complement of previously available methods (e.g., X-ray diffraction analysis), expectably, the proposed mass spectrometric method seems to be versatile for probing hydrogen bond energies.NNSF of China 21031004 21021061 U120511

The Coordination ways on the management of digital library consortia

建立有效的数字图书馆合作的利益机制，不能局限于单一地从技术、经济、法律或政治方面寻求解决方案，应该在矛盾运动中综合地运用各种手段

Test of the Performance of the Self-Designed Radio-frequency Ion Trap Mass Spectrometer Interfaced with a Laser Desorption Ion Source

自行研制了一台配置了激光离子源的射频离子阱质谱仪 ,并测试了该仪器的一些主要功能 .测试结果显示 :该仪器不仅能记录激光产生的正负离子的质谱 ,而且能实现离子质量选择存储和囚禁离子的共振射出 .测试结果与理论模拟的结果基本一致 .Performance of the radio- frequency ion trap mass spectrometer has been tested.The mass spectrometer is a home- made instrument interfaced with a laser desorption ion source.The experiment demonstrated that the instrument can not only record the mass spectrum of the cations and anions produced by the pulsed- laser beam but also exhibit the special functions,such as ion selective storage and resonant ejection of the ions in the trap. The observation of the experiment is consistent with the simulation result.国家自然科学基金资助项目!(2 97730 4 0

Electrochemical Investigation of Effect of Br - on Redox Behavior of (TPP)Co

用微电极和薄层循环伏安（ＣＶ）技术研究了Ｂｒ－对四苯基钴卟啉（（ＴＰＰ）Ｃｏ）在１，２＿二氯乙烷（ＤＣＥ）中电化学行为的影响．发现在较高电位下，两个Ｂｒ－轴向配位的（ＴＰＰ）Ｃｏ（ＩＩ）（Ｂｒ－）２其一个Ｂｒ－发生脱落表现出（ＴＰＰ）Ｃｏ（ＩＩ）（Ｂｒ－）的行为特征，这被证明是Ｂｒ－的氧化所致．证明了（ＴＰＰ）Ｃｏ（ＩＩ）（Ｂｒ－）在约０．１２Ｖ（ＳＣＥ）处还原，而（ＴＰＰ）Ｃｏ（ＩＩ）（Ｂｒ－）２则在大约Ｃｏ（Ｉ）／Ｃｏ（Ｉ）还原过程出现的更负的电位处发生还原The effect of Br - anion on electrochemical behavior of (TPP)Co was investigated in 1,2 dichloroethane solution by microelectrode and thin layer cyclic voltammetry technique. It was found that the axially coordination of one Br - anion to (TPP)Co(Ⅲ)(Br -) 2 shifts the potential of porphyrin system to more positive value. The reduction peak of 0.12 V(vs.SCE) is attributed to the reduction of (TPP)Co(Ⅲ)(Br -). It is also postulated that the reduction of (TPP)Co(Ⅲ)(Br -) 2 occurred at a more negative potential where the reduction of the Co(Ⅱ)/Co(Ⅰ) process happened.作者联系地址：中国科学院金属腐蚀与防护研究所金属腐蚀与防护国家重点实验室,中国科学技术大学化学系Author's Address: State Key Lab. for Corrosion and Prot., Inst. of Corr. and Prot. of Metals, Chinese Acad.of Sci., Shenyang 110015 Lin Xiangqin Dept. of Chem., Univ. of Sci. and Tec. of China, Hefei 230026$$

Theoretical Study on Geometric Structures and Electronic Properties of Clusters V_nP_m--+

对激光等离子体反应生成原子团簇VnPM＋进行了量子化学从头算研究，对可能的几何结构进行了试探性计算，并对其中较稳定构型进行了几何优化。结果表明，VPM＋中，V倾向与双磷成键形成平面结构，其中VP＋4、VP6＋较稳定。二钒磷化物形成一个生长螺线，从V2P4＋至V2P8＋，双钒之间间隔的磷原子组成准四面体、五边形、六面体…，多钒磷化物中VAPb＋与VAPb＋具有相同几何构型，其中V3P3＋、V4P4＋为三钒、四钒磷化物中最稳定的构型。Cluster VnPm+ generated by laser plasma reaction have been studied using quantumchemistry ab initio method.Possible geometric structures are examined and optimized.For VPm+,vanadium atom tends to combine with two phosphorus atoms to form planar systems, andVP4+ and VP6+ are more stable of them.There is one growing helices for V2F4+ -V2P8+, thenumber of phosphorus atoms between 2 vanadium atoms grow from four to eight, and thesephosphorous takes the shape of tetrahedron, pentagon, octahedron or cube ....It's found thatin many-vanadium phosphide VaPb+ and VbPa+ are of the same structure, which may berationalized by the fact that V and P have the same number of valence electrons.国家自然科学基金;福建省自然科学基