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Chinese Journal of Chemistry 2002年第12期20卷 1540-1545,1462页

作者：余翀天郭寅龙吕龙王韵华姚萍黄仲贤 Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 Department of Chemistry Fudan University Shanghai 200433

To elucidate the effect of various amino acid residues on the heme-binding pocket in cytochrome Tb 5, several residues were chosen for replacement by means of site-directed mutagenesis. Comparison of the mass spectrum between the F35Y mutant and the wild type shows that the relative abundance of holo-protein ion of F35Y is lower than that of the wild type in gas phase. It is concluded that mutation from Phe35 residue to tyrosine decreases the hydrophobic character of cytochrome Tb 5 heme pocket, which decreases the stability of heme-binding pocket. ESI-MS spectra of the mutants V61E, V61K, V61H and V61Y show various contribution of amino acid to the stability of heme-binding pocket. The small and non-polar residue Val61 was replaced with large or polar residues, resulting in enhancing the trend of heme leaving from the pocket. In addition, comparison of the mass relative abundance of holo-proteins among all the Val61-mutants, shows that their stability in gas phase appropriately submit the following order: wild type>V61H>V61E>V61K≈V61Y. The extra great stability of quadruple sites mutant E44/48/56A/D60A shows that reduction of electrostatic or hydrogen bond interactions among the residues locating in the outside region of the heme edge remarkably affect the stability of heme. The results of analyzing the oxidation states of heme iron in Tb 5 and its mutants by in-source-CAD experiment suggest that the charge states of heme iron maintain inflexible in mutation process

关键词： electrospray cytochrome Tb 5 mutants gas phase stability

DFT Study on the Os^+-catalytic Reduction Reaction of N_2O with H_2 in the gas phase

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Chinese Journal of Structural Chemistry 2011年第4期30卷 580-586页

作者：李涛洪王传铭余仕问谢小光 The Key Laboratory of Forest Resources Conservation and Use in the Southwest Mountains of China Southwest Forestry University Department of Biology Honghe University Department of Chemistry Qujing Normal University Department of Chemistry Yunnan University

The Os＋-catalytic reduction of N2O by H2 in gas phase has been theoretically investigated with B3LYP method.The reaction mechanisms on the sextet and quartet surfaces were found to be similar.The calculated sextet potential energy profiles show that the two reactions involved in the catalytic cycle,Os＋＋ N2O → OsO＋＋ N2 and OsO＋＋ H2 → Os＋＋ H2O,have barriers of 28.3 and 123.3 kJ/mol,respectively.In contrast,the reactions on the quartet surfaces are energetically much more favorable.These results rationalize the experimentally observed low catalytic reactivity of sextet（ground-state） Os＋.Further,the crossing between the sextet and quartet surfaces are also suggested and qualitatively discussed.

关键词： DFT gas phase catalytic reduction mechanism

gas phase Selective Catalytic Oxidation of Toluene to Benzaldehyde on V_2O_5-Ag2O/η-Al_2O_3 Catalyst

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Journal of Natural gas Chemistry 2004年第4期13卷 238-243页

作者： TonglaiZhang LiqiuMao WeihuaLiu StateKeyLaboratoryofPreventionandControlofExplosionDisasters BeijingInstituteofTechnologyBeijing100081China

gas phase selective catalytic oxidation of toluene to benzatdehyde was studied on V_2O_5-Ag_2O/η-Al_2O_3 catalyst prepared by impregnation. The catalyst was characterized by XRD, XPS, TEM, and FT-IR. The catalytic results showed that toluene conversion and selectivity for benzaldehyde on catalyst sample No.4 (V/(V+Ag)=0.68) was higher than other catalysts with different V/Ag ratios. This was attributed to the higher surface area, larger pore volume and pore diameter of the catalyst sample No. 4 than the other catalysts. The XRD patterns recorded from the catalyst before and after the oxidation reaction revealed that the new phases were developed, and this suggested that silver had entered the vanadium lattice. XPS results showed that the vanadium on the surface of No.4 and No.5 sample was more than that in the bulk, thus forming a vanadium rich layer on the surface. It was noted that when the catalyst was doped by potassium promoter, the toluene conversion and selectivity for benzaldehyde were higher than those on the undoped catalyst. This was attributed to the disordered structure of V_2O_5 lattice of the K-doped catalyst and a better interracial contact between the particles.

关键词： V_2_5-AgO gas phase selective catalytic oxidation toluene benzaldehyde

OES study of the gas phase during diamond films deposition in high power DC arc plasma jet CVD system

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Chinese Physics B 2006年第5期15卷 980-984页

作者：周祖源陈广超唐伟忠吕反修 School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

This paper used optical emission spectroscopy （OES） to study the gas phase in high power DC arc plasma jet chemical vapour deposition （CVD） during diamond films growth processes. The results show that all the deposition parameters （methane concentration, substrate temperature, gas flow rate and ratio of H2/Ar） could strongly influence the gas phase. C2 is found to be the most sensitive radical to deposition parameters among the radicals in gas phase. Spatially resolved OES implies that a relative high concentration of atomic H exists near the substrate surface, which is beneficial for diamond film growth. The relatively high concentrations of C2 and CH are correlated with high deposition rate of diamond. In our high deposition rate system, C2 is presumed to be the main growth radical, and CH is also believed to contribute the diamond deposition.

关键词： gas phase OES diamond film high power DC arc plasma jet CVD

First Step in Dissociation Process in the gas phase for Small Molecules with Neutral Atoms: Application with the Even-Odd Rule and a Specific Periodic Table for Organic and Inorganic Atoms

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Open Journal of Physical Chemistry 2021年第2期11卷 54-63页

作者： Geoffroy Auvert Grenoble Alpes University Grenoble France

Dissociations in the gas phase of small molecules have been intensively studied and dissociation energies of various gases are available in reference works. Configurations of compounds before and after the dissociation are usually known, but local charges are not defined. Building on the even-odd rule, the topic of a series of previous articles by the same author, the objective of this paper is to show how it can be used to give electronic rules for dissociations in gases. To this end, a specific periodic table is created and used. The rules are applied to a selection of more than 30 common molecules, showing that the even-odd rule and its consequences are useful in explaining the phenomenon of dissociation in gases.

关键词： Dissociation First Step gas phase Molecule Covalent Bond Even-Odd Rule

Pure Metal Clusters with Atomic Precision for Nanomanufacturing

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Nanomanufacturing and Metrology 2022年第3期5卷 230-239页

作者： Haiming Wu Hanyu Zhang Lijun Geng Yuhan Jia Benben Huang Mengzhou Yang Baoqi Yin Xin Lei Zhixun Luo Beijing National Laboratory for Molecular Sciences(BNLMS)and State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Advances in cluster science have enabled the preparation of atomically precise metal clusters with one to a hundred atoms under controllable expansion conditions.After introducing typical gas-phase cluster preparation and reaction apparatuses,this work summarized recent progress in preparing pure metal clusters of single-atom resolution,including neutral and ionic ones,with typical examples of Al,V,Nb,Fe,Co,Ni,Rh,Pt,Ag,Cu,and Pb.With the development of soft-landing deposition technology,the size-selective pure metal clusters with strict atomic precision and predictive property will benefit nanomanufacturing down to atomic and near-atomic scales.This work serves as a modest motivation to stimulate the interest of scientists focusing on interdisciplinary subjects.

关键词： Metal cluster gas phase Cluster assembly Deposition Printing

In-situ Formation of MgAl_(2)O_(4):A Method of Tailoring Microstructure and Properties for Development of High-performance Refractories

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China's Refractories 2023年第2期32卷 1-6页

作者： LIU Guoqi WANG Minghui LI Hongxia YU Jianbin GAN Feifang GU Qiang MA Weikui State Key Laboratory of Advanced Refractories Sinosteel Luoyang Institute of Refractories Research CoLtd.Luoyang 471039China Zhengzhou University Zhengzhou 450052China BaoshanIron&SteelCo. Ltd.Shanghai 201900China

The in-situ formation mechanism of MgAl_(2)O_(4) was introduced,focusing on the formation process by solid phase reaction and gas phase reaction as well as the phenomenon of secondary spinelization.The influencing factors of the in-situ MgAl_(2)O_(4) formation and its effect on the microstructure and the properties of materials were systematically summarized for the Al2O3-MgO-MgAl_(2)O_(4) system and the carbon-containing refractories systems.It was pointed out that the in-situ formation of MgAl_(2)O_(4),including secondary spinelization,can regulate the microstructure and the service performance of materials.Its expansion effect can not only offset the shrinkage caused by sintering to improve the corrosion resistance of refractories,but also seriously restrict the reliability of functional refractories.The composition,the particle size,the atmosphere,and the temperature are important factors affecting the in-situ formation of MgAl_(2)O_(4).In the carbon-containing materials systems,the solid-solid reaction and the gas-solid reaction coexist to produce MgAl_(2)O_(4),which provides an effective way to further regulate the microstructure and the properties of materials through the reaction process.

关键词： Al_(2)O_(4) in-situ,spinalization gas phase secondary spinalization high temperature

Infrared Spectroscopy of Neutral and Cationic Pyrrolidine Monomer in Supersonic Jet

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Chinese Journal of Chemical Physics 2020年第1期33卷 43-47,I0005,I0006页

作者： Min Xie Zhao-li Zhang Yu Zhang Xiao-nan Sun Fu-fei Sun Yong-jun Hu MOE Key Laboratory of Laser Life Science&Guangdong Provincial Key Laboratory of Laser Life Science Guangzhou Key Laboratory of Spectral Analysis and Functional ProbesCollege of BiophotonicsSouth China Normal UniversityGuangzhou 510631China

Pyrrolidine,a five membered heterocyclic molecule,is widely existing in organism.Herein,infrared spectra of pyrrolidine monomer in neutral and cationic states were obtained by vacuum ultraviolet ionization,infrared photodissociation and time of flight mass spectrometry.Both in neutral and cationic states,it is found that their CH stretching vibration bands are red shifted.In the IR spectrum of neutral pyrrolidine,because the electric dipole moment of NH is small,we have not observed the NH stretching vibration bands.However,the NH stretching vibration band of pyrrolidine is greatly enhanced after ionization,and this band red-shifts compared with the previous experiment.The red shifts of CH stretching vibrations in neutral and cationic states are caused by the negative and positive hyperconjugation,respectively.The enhancement and red shift of the NH stretching band are owing to the ejection of the electrons on the N atom after ionization.Through the calculations,it is found that the acidity of the CH bond is a little stronger than that of NH bond.These kinds of studies would be helpful to understand the intrinsic properties of biomolecules in neutral and cationic states,and to provide reference for the further study of living organic macromolecules.

关键词： IR spectroscopy Hyperconjugation Cationic state CH bond acidity gas phase

Influence of Rain on Tetrachloroethylene's Multiphase Migration in Soil

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Journal of Earth Science 2015年第3期26卷 453-460页

作者： Yong Qian Jingli Shao Zhaoji Zhang Yuhong Fei Chunxiao Wang Xiangxiang Cui Suhua Meng School of Water Resources & Environment China University of Geosciences The Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological Sciences Hebei Key Laboratory of Groundwater Remediation

For the increasingly serious soil and groundwater pollution by volatile organic compounds, tetrachloroethylene（PCE） was selected as the research object in this study. With the in-situ soil column physical simulation experiments, migration law of PCE in soil under rain conditions was studied by monitoring precipitation and soil parameter as well as sampling and analyzing soil and soil gas, and influence of rain on the multiphase migration process of PCE was preliminarily discussed. Research shows that migrations of PCE and soil moisture were not synchronous, and the rate of the former was speeded up by the latter caused by rain. Preliminary analysis indicates that migration of volatile chlorohydrocarbon in soil was not only driven by soil moisture, but also controlled by the nature of volatility of their own, that is to say, volatilization into gas phase was an important way of migrating and diffusing in pore medium, and the rate of migration and diffusion of gaseous PCE was faster than that of solid, resulting in more abroad distribution of gas phase than that in solid phase.

关键词： volatile organic pollution soil water migration tetrachloroethylene（PCE） gas phase

FT-ICRMS在团簇化学中的应用(Ⅱ)--第一过渡系金属离子与丙炔醇的吸附和反应

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分析测试学报 2001年第Z1期20卷 114-115页

作者：辛斌赵翔蒲丹胡伟华熊少祥王光辉高正中国科学院化学研究所分子科学中心北京质谱中心北京100080

近10多年以来,金属离子及其团簇离子在气相中的吸附、催化和反应得到了广泛的关注.在去除溶剂化效应、离子对等干扰的条件下,一些金属有机化合物的反应活性及其催化机理得到了更本质的阐述[1-4].由于过渡金属元素因其外层价电子结构利... 详细信息

近10多年以来,金属离子及其团簇离子在气相中的吸附、催化和反应得到了广泛的关注.在去除溶剂化效应、离子对等干扰的条件下,一些金属有机化合物的反应活性及其催化机理得到了更本质的阐述[1-4].由于过渡金属元素因其外层价电子结构利于插入有机键,使其对大量的有机物都具有反应活性[5].我们探讨了第一过渡系金属离子与丙炔醇的吸附和反应[6].本文介绍利用傅利叶变换离子回旋共振质谱(FT-ICRMS)研究气相中第一过渡系金属离子与丙炔醇的吸附和反应,得到了一些有意义的结果,并讨论了其规律和机理.……

关键词：团簇化学应用过渡系金属离子丙炔醇吸附 gas phase 反应活性金属有机化合物过渡金属元素溶剂化效应价电子结构团簇离子气相离子回旋催化机理共振质谱有机物叶变换离子对外层