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A Note on Holonomy of Gerbes over Orbifolds

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Acta Mathematica Sinica,English Series 2013年第10期29卷 1973-1980页

作者： xiao qin YIN Mathematical College Sichuan University

In this paper, we generalize the construction of the inverse transgression map done by Adem, A., Ruan, Y. and Zhang, B. in [A stringy product on twisted orbifold K-theory. Morfismos, 11, 33 64 （2007）] and give a different proof to the statement that the image of the inverse transgression map for a gerbe with connection over an orbifold is an inner local system on its inertia orbifold.

关键词： Gerbe orbifold Lie groupoid inner local system holonomy

A Novel 3D Supramolecular Network Constructed from [Cu(4,4'-bipyridine)(O_2CMe)_2]_2 Molecular Ladders by Hydrogen Bonding

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Chinese Journal of Structural Chemistry 2006年第11期25卷 1365-1368页

作者： YANG E WANG xiao-qin qin Ye-Yan College of Chemistry ＆ Materials Science Fujian Normal University Fuzhou 350007 China Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou 350002 China

The title complex, {[Cu2（4,4＇-bipyridine）2（μ-O2CMe）2（O2CMe）2],H2O}n 1, was synthesized and structurally characterized by X-ray crystallography. It crystallizes in monoclinic, space group C2/c with a = 13.4474（5）, b = 11.7566（2）, c = 19.5380（6）A, β = 92.930（2）°, V = 3084.84（16） A^3, Z = 4, Cu2C28N409H30, Mr = 693.64, Dc = 1.494 g/cm^3, F（000） = 1424 and μ（MoKα） = 1.436 mm^-1. With the use of 2062 observed reflections （I 〉 2σ（I））, the structure was refined to R = 0.0769 and wR = 0.2154. In complex 1, the dimeric copper acetate units are linked through 4,4’-bipyridine to yield ID molecular ladders. These ladders are connected via O-H…O hydrogen bonds to generate 2D layers, which are further linked through C-H…O hydrogen bonds to give a 3D supramolecular network.

关键词： molecular ladder dimeric copper acetate 3D supramolecular network

Activating AIN thin film by introducing Co nanoparticles as a new anode material for thin-film lithium batteries

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Rare Metals 2018年第8期37卷 625-632页

作者： Zhong Yan xiao-Ye Niu xiao-qin Du qin-Chao Wang xiao-Jing Wu Yong-Ning Zhou Department of Materials Science National Microanalysis CenterFudan University

A1N/Co nanocomposite thin films were fabricated by pulsed laser deposition and investigated as new anode materials for lithium-ion batteries for the first time. The combination of electrochemically inactive A1N and Co in nanometer scale boosted the electrochemical performance of the thin films surprisingly. A high reversible capacity of 555 mAh.g^-1 after 100 discharge-charge cycles at a current density of 500 mA.g^-1 is obtained for the A1N/Co nanocomposite thin films, and 372 mAh.g^-1 can be retained at a high rate up to 16C, exhibiting promising cycle stability and rate capability. The electrochemical reaction mechanism study reveals that Co nanoparticles could not only provide high electronic conductivity for the thin films, which facilitate the thorough decomposition of A1N in the initial discharge process, but also react with Li3N to form a new species CozN during charge process, thus ensuring large capacity and high reversibility of A1N/Co nanocomposite thin films in sub- sequent cycles. This study provides a new perspective to design advanced electrode materials for lithium-ion batteries.

关键词： Lithium-ion battery Anode material Thinfilm Aluminum nitride Pulsed laser deposition

Modification of FGD gypsum in hydrothermal mixed salt solution

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Journal of Environmental Sciences 2006年第1期18卷 170-175页

作者： WU xiao-qin WU Zhong-biao Department of Environmental Engineering Zhejiang University Hangzhou 310027 China Department of Chemical Engineering Wuhan University of Science and Technology Wuhan 430081 China

A novel utilization way of the sludge from wet calcium-based flue gas desulfurization （FGD） processes has been developed in this paper. This study focused on the conversion of the FGD gypsum into α-hemihydrate calcium sulfate by a hydrothermal salt solution method at atmospheric pressure. Experimental study has been carried out in a batch reactor. Qualitative and quantitative analyses were made by DSC/TG thermal analysis, SEM, XRD, metalloscope and chemical analysis. The experimental results showed that the modification of FGD gypsum was controlled by the dissolution and recrystallization mechanisms. With the introduction of FGD gypsum the salt solution was supersaturated, then crystal nucleus of α-hemihydrate calcium sulfate were produced in the solution. With the submicroscopic structure of FGD gypsum crystal changed, the crystal nucleus grew up into α-hemihydrate calcium sulfate crystals. Thus ,the modification of FGD gypsum was fulfilled.

关键词： FGD gypsum modification hydrothermal mixed salt solution atmospheric pressure

State reconstruction of molecular spatial rotation

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Chinese Physics B 2012年第2期21卷 81-87页

作者： qin xiao Gao Jun-Yi Wuhan Institute of Physics and Mathematics Chinese Academy of SciencesWuhan 430071China Graduate University of the Chinese Academy of Sciences Beijing 100049China

We establish a reconstruction approach for the rotational quantum state of linear molecules possessing a magnetic manifold. Our approximate method contains an iteration with generalized matrix inverses, processing the tomographic integral of the time-dependent molecular-axis distribution in a polar angle. As shown in a simulated example for an alignment state, the density matrix is determined in a high fidelity. An analytic tomographic formula is also derived for the symmetric top rotation. The state coherent in the quantum space of both the angular momentum and its magnetic projection can be approximately retrieved from the observable time-resolved solid-angle distribution of the molecular axis.

关键词： state reconstruction molecular rotation

Catalytic Performance of MnO_x-WO_3/TiO_2 Catalyst for Selective Catalytic Reduction of NO_x with NH_3 and Its Tolerance Towards SO_2

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Chemical Research in Chinese Universities 2009年第6期25卷 914-919页

作者： WU Bi-jun LIU xiao-qin xiao Ping State Power Environmental Protection Research Institute of China Guodian Corporation Nanjing 210031 P R. China Chemical Engineering Institute Nanjing University of Technology Nanjing 210009 P. R. China

The performance of Mn-W/TiO2 for selective catalytic reduction（SCR） of NOx with NH3 and its resistance to different concentrations of SO2 at various temperatures were investigated. The results show that WO3 increased the active sites and enhanced the strength of acid, so it was an effective promoter of MnOJTiO2. The NOx conversion on Mn-W/TiO2 ranges from 80.3% to 99.6% between 100 ℃to 350℃ at GHSV=18900 h 1, while N2 product selectivity changes from 100% to 98.7%. In the presence of 0.01% SO2 and 6% H20, NOx conversion maintained 98.5% at 120℃. The influence of more than 0.01% SO2 on the activity of MnOx-WO3/TiO2 will disappear if the temperature rises above 250℃. By means of heating and sweeping with He, the activity of the catalysts can be recovered. At 300℃, NOx conversion yielded 99% with 0.07% SO2 and reached the level of commercial V-W/TiO2 catalysts. The Mn-W/TiO2 catalyst showed excellent performance for SCR of NOx with NH3 in a wider range of temperature with strong tolerance to SO2.

关键词： Selective catalytic reduction NOx MnOx-WO3/TiO2 Catalytic performance

Creation of Coherent Superposition States in Multilevel Systems

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Communications in Theoretical Physics 2007年第5X期48卷 908-912页

作者： qin Jia-Qian KUANG Ye SHU xiao-qin Department of Physics Sichuan University Chengdu 610064 China

A powerful approach to generate multilevel superposition state in A-type manifold of levels is proposed. In the analysis, we introduce a group of rotations to transform the coupled system to a simpler form, which involves one coupled and several decoupled, dark states in the ground state manifold. Then an arbitrary superposition state of initial and final states can be created. In particular, when the Rabi frequencies of the Stokes pulses have equal magnitudes, a superposition state （equal population of the （n - 2） superposition states） will be generated. A numerical simulation of coherence generation is given. It is shown that a small transient population in metastable state decreases as the intensity of Stokes pulses increases. Experimental implementation in Neon atom is given.

关键词： v coherent superposition state degenerate dark state

On Generic Extensions of Representations of a Dynkin Quiver of Type D

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Acta Mathematica Sinica,English Series 2005年第3期21卷 613-622页

作者： xiao qin DENG Jiang Rong CHEN School of Sciences Beijing Jiaotong University Beijing 100044 P. R. China Department of Mathematics Beijing Normal University Beijing 100875 P. R. China

The notion of generic extensions of representations of a Dynkin quiver plays a big role in the study of the structure of the corresponding quantum group. In this paper, we describe the generic extensions of a simple representation by any representation and that of any representation by a simple representation of a Dynkin quiver Q of type D.

关键词： Dynkin quiver Representation Generic extension

Performance and Kinetics Studies on Selective Catalytic Reduction of NOx with NH_3 over MnO_x-WO_3/TiO_2 Catalyst

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Chemical Research in Chinese Universities 2010年第6期26卷 1002-1006页

作者： WU Bi-jun xiao Ping LIU xiao-qin Guodian Science and Technology Research Institute Nanjing 210031 P R. China Chemical Engineering Institute Nanjing University of Technology Nanjing 210009 P. R. China

The catalytic activities of MnOx-WO3/TiO2 for selective catalytic reduction（SCR） of NO with NH3 were investigated in a wide range of temperature and reaction *** yielded a NOx conversion of 80.3%—99.6% and a N2 product selectivity of 100%—98.7% during 100 °C to 350 °C at gas hourly space velocity（GHSV）=18900 *** the presence of 0.01% SO2 and 6% H2O at 120 °C,the NOx conversion can maintain 98.5%.At 300 °C and with 0.07% SO2 in reactant stream,the NOx conversion stabilized at 99% as high as the commercial V-W/TiO2 catalyst＇s *** steady-state kinetics study shows that O2 played a promoting *** the presence of less than 1.5% O2,NOx conversion can increase sharply with the increase of O2 *** reaction order was zero with respect to NH3 and first with respect to NO with excess O2 and *** kinetics active energy（Ea） of Mn-W/TiO2 was calculated to be 6.24 kJ/mol according to the kinetic experiment at various temperatures,much lower than those of other catalysts reported in the ***-W/TiO2 is an excellent catalyst for SCR of NO with NH3 by now.

关键词： Selective catalytic reduction of NO with NH3 MnOx-WO3/TiO2 Performance Kinetics