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IMP & HIRFL Annual Report 2014年第1期 82-83页

作者： Cao Shiwei Qin Zhi Wang Yang 不详

In this work, gas-phase chemistry of ruthenium and rhodium was studied using online isothermal chromatographyapparatus at low temperature coupled to the 252Cf SF source[1] at IMP (Fig. 1). Apart from the interferenceof precursor effect[2], 109?110Ru and 111?112Rh were chosen as the representative isotopes for the two elementsrespectively. An improved Monte Carlo molecular simulation program was compiled according to the gas-phasechemistry model[3], and was used in the optimization of the experimental condition. The adsorption enthalpies ofpentacarbonyl ruthenium and tetracarbonyl rhodium on the FEP surface were obtained.

关键词： gas-phase Chemistry Study

Synthesis of dimethyl carbonate by gas-phase oxidative carbonylation of methanol in the presence of solid catalyst I. Catalyst preparation and catalytic Properties

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河北工业大学学报 1997年第A1期26卷 100-109页

作者： Wang Yanji Zhao Xinqiang Yuan Baoguo Zhang Bingchang and Cong Jinsheng(Department of Chemical Engineering, Hebci University) of Technology300130 Tianjin Parole’s Republic of China)

The gas-phase synthesis of dimethyl carbonate (DMC) from methanol, carbon monoxide and oXygen has here Studied in a flow system at atomspheric Pressure. A series of Catalyst used in this reaCtion have been prepared and evaluated. The influence of trivared carbon supporters, alkaline metal Promoters and operation conditions on DMC opthesis reaction has been discussed. Under the conditions of 130℃, CO/O2=1 .96, SV=3340h-1, the space-time yield (STY) of DMC over PdCl2-CuCl2-CH3COOK/ac. catalyst is 217g/l-cat h,which is higher than what is published in the literatUre so far.

关键词： Dimethyl Carbonate synthesis Solid catalyst Methanol gas-phase oxidative carbonylation.

Vibrational spectroscopy of the mass-selected tetrahydrofurfuryl alcohol monomers and its dimers in gas phase using IR depletion and VUV single photon ionization

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Vibrational spectroscopy of the mass-selected tetrahydrofurf...

An Effective Method of Producing Small Neutral Carbon Clusters

第十五届全国化学动力学会议

作者：宋文韬 Yujian Li Yongjun Hu MOE Key Laboratory of Laser Life Science & Institute of Laser Life Science College of BiophotonicsSouth China Normal University

Tetrahydrofurfuryl alcohol(THFA,CHO) is a close chemical analog of the sugar rings present in the phosphate-deoxyribose backbone structure of the nucleic *** present report,the infrared(IR) spectra of the size-selected THFA monomer and its dimer have been investigated in a pulsed supersonic jet using infrared-vacuumultraviolet(VUV) ***,the laser light at 118 nmwavelength served as the source of "soft" ionization in a time-of-flight mass *** IR features for the monomers located at 3622 cm can be assigned to the intramolecular hydrogen bonding stretch vibrations mainly referring to A and C *** with the monomer,however,characteristic peaks for the dimer centered at 3415 and 3453 cm,red shifted 207 and 169 cm,respectively,were associated with the intermolecular hydrogen bonding stretch *** with the quantum-chemical calculations,the dimer in the gas phase preferred cyclic AC conformer stabled by forming two strong intermolecular hydrogen bonds,which shown the high hydrogen bond selectivity in the *** conclusions drawn from the role played in the conformational flexibility by the hydroxyl and ether groups may be extended to other biomolecules.

关键词： Tetrahydrofurfuryl alcohol Tetrahydrofurfuryl alcohol’s dimer gas-phase IR spectroscopy Hydrogen bonding

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Chinese Physics Letters 2007年第7期24卷 1912-1914页

作者：夏柱红陈正竹许艳珠 Department of Physics Southeast University Nanjing 211189 Institute of Atomic and Molecular Sciences Academia Sinica Taipei

An effective method of producing small neutral carbon dusters Cn （n = 1-6） is described. The small carbon dusters （positive or negative charge or neutral） are formed by plasma which are produced by a high power 532nm pulse laser ablating the surface of the metal Mn rod to react with small hydrocarbons supplied by a pulse valve, then the neutral carbon clusters are extracted and photo-ionized by another laser （266nm or 355nm） in the ionization region of a linear time-of-flight mass spectrometer. The distributions of the initial neutral carbon dusters are analysed with the ionic species appeared in mass spectra. It is observed that the yield of small carbon dusters with the present method is about 10 times than that of the traditional widely used technology of laser vaporization of graphite.

关键词： ELECTRONIC SPECTROSCOPY METALLO-CARBOHEDRENES gas-phase CHAINS C-3 SPECTRUM IONS BAND

Thermal benzene activation by 3d transition metal(Sc-Cu) oxide cations

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Chinese Chemical Letters 2020年第3期31卷 779-782页

作者： Jiatong Cui Yue Zhao Ming Wang Shanshan Wang Jiabi Ma Key Laboratory of Cluster Science of Ministry of Education Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion MaterialsSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China Analysis&Testing Center Beijing Institute of TechnologyBeijing 100081China

Considering the importance and complexity of benzene oxidation on mineral oxide aerosol surfaces in the atmosphere,gas-phase 3 d-transition metal oxide cations were used as models of active sites on mineral oxide aerosols to mimic the corresponding *** various cations have been prepared by laser ablation and reacted with benzene in a linear ion trap *** the 103 systematically investigated cations,39 clusters can oxidize benzene at room *** addition to the adsorption channel,other five types of reaction channels were observed,including dehydrogenation of C6H6,charge exchange,hydrogen atom transfer,oxygen atom transfer,and the formation of C6H5O^+radical,among which the first two pathways are prevale nt and the formation of C6H6O^+cations has not been reported in *** insight into the benzene oxidation reactions derived from the gas-phase model systems is helpful to build a detailed picture of oxidative mechanisms of C6H6 and its derivatives over corresponding mineral oxide aerosols.

关键词： gas-phase reactions Transition metal oxide cations Benzene Mass spectrometry Ion-molecular reaction

The heterogeneous oxidation of SO_2 on aerosol surface

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Science China Earth Sciences 1997年第5期40卷 518-523页

作者：高会旺黄美元徐华英 Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

A heterogeneous chemical model is developed by coupling aerosol, gas-phase and liquid-phase chemical model. SO2 oxidation rates on the aerosol surface are calculated and the influence of some factors is discussed. Model simulations indicate that SO2 heterogeneous oxidation rates are sensitive to the mass concentration and chemical composition of aerosols, relative humidity, initial values of SO2 and H2O2. The heterogeneous chemical model is coupled with a Eulerian deposition model. Model results show that oxidation of SO2 on the aerosol surface is found to reduce SO2 levels by 5%-33%, to increase SO2-4 concentrations by 8%-50% in the surface layer.

关键词： gas-phase chemistry liquid-phase chemistry aerosol heterogeneous chemical model sulfur deposition

Development and Catalytic Cracking Performance of Ultrastable Y Zeolite Rich in Secondary Pores

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China Petroleum Processing & Petrochemical Technology 2024年第2期26卷 13-21页

作者： Li Jiaxing Wang Shengji Sha Hao Wang Juan Zhou Lingping Wang Lixia SINOPEC Research Institute of Petroleum Processing Co. LtdBeijing 100083China Catalyst Co. Ltd.Qilu BranchSINOPECZibo 255336China

A novel ultra-stable zeolite, NSZ, rich in secondary pores was developed through the combination of gas-phase andmild hydrothermal methods. This zeolite was successfully tested in an industrial setting for the first time in the world. The porestructure characteristics of the NSZ zeolite prepared for industrial use were analyzed and characterized using BET. The resultsindicate a significant increase in the secondary pore volume of NSZ zeolite compared to the existing ultra-stable zeolite HSZ-5, which is produced through a conventional gas-phase method. The average secondary pore volume to total pore volume ratioin NSZ zeolite was found to be 58.96% higher. The catalytic cracking performance of NSZ zeolite was evaluated. The resultsshowed that the NSC-LTA catalyst, with NSZ as the active component, outperformed the HSC-LTA catalyst with HSZ-5 zeolitein terms of obtaining more high-value products (gasoline and liquefied petroleum gas) during the hydrogenated light cycle oilprocessing. Additionally, the NSC-LTA catalyst showed a significant improvement in coke selectivity.

关键词： gas-phase ultra-stable zeolite catalyst catalytic cracking

Anatomical backgrounds on gas exchange parameters in the lung

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World Journal of Respirology 2019年第2期9卷 8-29页

作者： Kazuhiro Yamaguchi Takao Tsuji Kazutetsu Aoshiba Hiroyuki Nakamura Shinji Abe Department of Respiratory Medicine Tokyo Medical University Department of Respiratory Medicine Tokyo Medical University Ibaraki Medical Center

Many problems regarding structure-function relationships have remained unsolved in the field of respiratory physiology. In the present review, we highlighted these uncertain issues from a variety of anatomical and physiological viewpoints. Model A of Weibel in which dichotomously branching airways are incorporated should be used for analyzing gas mixing in conducting and acinar airways. Acinus of Loeschcke is taken as an anatomical gas-exchange *** it is difficult to define functional gas-exchange unit in a way entirely consistent with anatomical structures, acinus of Aschoff may serve as a functional gas-exchange unit in a first approximation. Based on anatomical and physiological perspectives, the multiple inert-gas elimination technique is thought to be highly effective for predicting ventilation-perfusion heterogeneity between acini of Aschoff under steady-state condition. Changes in effective alveolar P_(O2), the most important parameter in classical gas-exchange theory, are coherent with those in mixed alveolar P_(O2) decided from the multiple inert-gas elimination technique. Therefore, effective alveolar-arterial P_(O2) difference is considered useful for assessing gas-exchange abnormalities in lung ***, one should be aware that although alveolar-arterial P_(O2) difference sensitively detects moderately low ventilation-perfusion regions causing hypoxemia, it is insensitive to abnormal gas exchange evoked by very low and high ventilation-perfusion regions. Pulmonary diffusing capacity for CO (D_(LCO))and the value corrected for alveolar volume (V_(AV)), i.e., D_(LCO)/V_(AV) (K_(CO)), are thought to be crucial for diagnosing alveolar-wall damages. D_(LCO)-related parameters have higher sensitivity to detecting abnormalities in pulmonary microcirculation than those in the alveolocapillary membrane. We would like to recommend four categories derived from combining behaviors of D_(LCO) with those of K_(CO) for differential diagnosis on anat

关键词： Secondary lobule of miller Acinus of Loeschcke Acinus of Aschoff Convection gas-phase diffusion(stratification) Aqueous-phase diffusion Ventilationperfusion heterogeneity