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Studies on the Quantitative Structure-activity Relationship of Substituted Biphenyls by Density Function Theory (DFT)

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Chinese Journal of Structural Chemistry 2007年第2期26卷 229-233页

作者： HAN xiang-Yun ZHENG qing Department of Chemical Engineering YanchengInstitute of Technology Jiangsu 224003 China

Geometrical configurations of 16 substituted biphenyls were computed at the B3LYP/6-311G^＊＊ level with Gaussian 98 program. Based on linear solvation energy theory, lgKow as well as the structural and thermodynamic parameters obtained at this level was taken as theoretical descriptors, and corresponding equation predicting the toxicity of Daphnia magna （-lgEC5o） was thus obtained, in which three parameters were contained, i.e., n-octanol/water partition coefficients （lgKow）, dipole moment of the molecules（ μ） and entropy （S°）. For this equation, R^2 = 0.9582, q^2 = 0.8921 and SD = 0.102. The absolute t-scores of three variables are larger than the standard one in the confidence range of 95%, which confirms the creditability and stability of this model.

关键词： substituted biphenyl linear solvation energy theory,DFT method Daphnia magna toxicity

SUPG finite element method based on penalty function for lid-driven cavity flow up to Re = 27500

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Acta Mechanica Sinica 2016年第1期32卷 54-63页

作者： Da-Guo Wang qing-xiang Shui School of Environment and Resources Southwest University of Science and Technology

A streamline upwind/Petrov-Galerkin （SUPG） finite element method based on a penalty function is pro- posed for steady incompressible Navier-Stokes equations. The SUPG stabilization technique is employed for the for- mulation of momentum equations. Using the penalty function method, the continuity equation is simplified and the pres- sure of the momentum equations is eliminated. The lid-driven cavity flow problem is solved using the present model. It is shown that steady flow simulations are computable up to Re = 27500, and the present results agree well with previous solutions. Tabulated results for the properties of the primary vortex are also provided for benchmarking purposes.

关键词： Streamline upwind/Petrov-Galerkin (SUPG)finite element method Lid-driven cavity flow Penaltyfunction method High Reynolds number

Synthesis and Structural Study of a N-Heterocyclic Carbene Trinuclear Silver(Ⅰ)Complex

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Chinese Journal of Structural Chemistry 2016年第2期35卷 313-318页

作者： LIU Jun HUO Ran WEI qing ZHAO Zhi-xiang LIU qing-xiang Tianjin Key Laboratory of Structure and Performance for Functional Molecules Key Laboratory of Inorganic-organic Hybrid Functional Material ChemistryMinistry of Education College of ChemistryTianjin Normal UniversityTianjin 300387China

The bis-benzimidazolium salt bis[2-（N-ethylbenzimidazoliumyl）ethyl]amine hexafluorophosphate（LH2·（PF6）2） and its N-heterocyclic carbene silver（Ⅰ） complex[L2Ag3]（PF6）3（1）have been prepared and *** complex 1,a trinuclear silver（Ⅰ） architecture is formed by two tridentate ligands and three silver（I） atoms,in which one 12- and two 7-membered rings are *** the crystal packing of 1,1D chain and 2D supramolecular layer are formed via intermolecular weak interactions,including π…π interactions and C-H…π ***,the fluorescence emission spectra of LH2-（PF6）2 and 1 are described.

关键词： carbene silver(I) complex bis-benzimidazolium salt

Synthesis and Crystal Structure of a Dinuclear Cu(Ⅱ) Complex [Cu(C_(13)H_9N_2O)Cl]_2·(CH_3CN)_2 with Ligand 2-Benzimidazol

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Chinese Journal of Structural Chemistry 2007年第2期26卷 149-152页

作者： LI qing-xiang YANG xiang-Liang XU Hui-Bi Hubei Key Laboratory of Novel Chemical Reactor andGreen Chemical Technology Wuhan Institute of Technology Wuhan 430073 China College of Life Science Huazhong University of Science and Technology Wuhan 430074 China

A new dinuclear copper complex, [Cu（C13HgN2O）Cl]2.（CH3CN）2 （C30H24C12Cu2N6O2）, has been synthesized and characterized by X-ray structure determination. It crystallizes in the triclirile system, space group P1, with a = 7.6677（14）, b = 9.2375（17）, c = 11.227（2） ]A, α = 81.338（3）,β = 88.173（4）, γ = 66.199（3）°, V = 718.9（2） ]A^3, Z = 1, Mr = 698.53, F（000） = 354, Dc = 1.613 g/cm^3, μ（MoKa） = 1.705 mm^-1, the final R = 0.0645 and wR = 0.1364 for 2474 unique reflections with 1809 observed ones （I 〉 20（I））. In the title complex, each copper（H） atom is located at the center of a distorted tetrahedron consisting of four coordinate atoms （one nitrogen atom, two oxygen anions, and one chlorine atom）. Two copper（Ⅱ） atoms are bridged by two oxygen anions （O（1） and O（la）） of two phenolates to form a Cu（Ⅱ）-Cu（Ⅱ） binuclear entity, and the distance between two copper（Ⅱ） atoms is 3.0144（15） A.

关键词： 2-benzimidazol phenolate Cu(Ⅱ) complex crystal structure

On Cauchy Problem of the Benney-Lin Equation with Low Regularity Initial Data

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Acta Mathematica Sinica,English Series 2009年第12期25卷 2157-2168页

作者： xiang qing ZHAO Shang Bin CUI Department of Mathematics Zhejiang Ocean University Zhoushan 316000 P. R. China Department of Mathematics Shanghai University Shanghai 200444 P. R. China Institute of Mathematics Sun Yat-Sen University Guangzhou 510275 P. R. China

In this work we prove that the initial value problem of the Benney-Lin equation ut ＋ uxxx ＋ β（uxx ＋ u xxxx）＋ ηuxxxxx ＋ uux = 0 （x ∈ R, t ≥0 0）, where β 〉 0 and η∈R, is locally well-posed in Sobolev spaces HS（R） for s ≥ -7/5. The method we use to prove this result is the bilinear estimate method initiated by Bourgain.

关键词： Benney-Lin equation initial value problem local well-posedness

Investigation of turbulence and skin friction modification in particle-laden channel flow using lattice Boltzmann method

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Applied Mathematics and Mechanics(English Edition) 2018年第4期39卷 477-488页

作者： Ming PAN qing xiang Shuai TANG Yuhong DONG Shanghai Institute of Applied Mathematics and Mechanics Shanghai UniversityShanghai 200072China Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai UniversityShanghai 200072China

Interaction between turbulence and particles is investigated in a channel flow. The fluid motion is calculated using direct numerical simulation(DNS) with a lattice Boltzmann(LB) method, and particles are tracked in a Lagrangian framework through the action of force imposed by the fluid. The particle diameter is smaller than the Kolmogorov length scale, and the point force is used to represent the feedback force of particles on the turbulence. The effects of particles on the turbulence and skin friction coefficient are examined with different particle inertias and mass loadings. Inertial particles suppress intensities of the spanwise and wall-normal components of velocity, and the Reynolds shear stress. It is also found that, relative to the reference particle-free flow,the overall mean skin-friction coefficient is reduced by particles. Changes of near wall turbulent structures such as longer and more regular streamwise low-speed streaks and less ejections and sweeps are the manifestation of drag reduction.

关键词： lattice Boltzmann(LB) equation particle channel flow turbulence modulation skin friction

A novel highly selective fluorescent chemosensor for Hg(Ⅱ) in fully aqueous media

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Chinese Chemical Letters 2007年第10期18卷 1209-1212页

作者： xiang Ming Meng Man Zhou Zhu qing xiang Guo Department of Chemistry University of Science and Technology of China Hefei 230026 China

A novel fluorescent Hg^2＋ chemosensor based on dithia-dioxa-monoaza crown ether was synthesized in four steps from inexpensive starting materials. This new sensor exhibited very strong fluorescence response to Hg^2＋... 详细信息

关键词： Hg^2+ sensor Fluorescence PET Fluorescein Selectivity

How to enhance the ability of mesenchymal stem cells to alleviate intervertebral disc degeneration

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World Journal of Stem Cells 2023年第11期15卷 989-998页

作者： qing-xiang Zhang Min Cui Department of Critical Care Medicine Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022Hubei ProvinceChina Department of Critical Care Medicine Wuhan Jinyintan HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430048Hubei ProvinceChina Department of Orthopedics Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022Hubei ProvinceChina

Intervertebral disc(ID)degeneration(IDD)is one of the main causes of chronic low back pain,and degenerative lesions are usually caused by an imbalance between catabolic and anabolic processes in the *** environment in which the ID is located is harsh,with almost no vascular distribution within the disc,and the nutrient supply relies mainly on the diffusion of oxygen and nutrients from the blood vessels located under the *** stability of its internal environment also plays an important role in preventing *** main feature of disc degeneration is a decrease in the number of *** stem cells have been used in the treatment of disc lesions due to their ability to differentiate into nucleus pulposus cells in a nonspecific anti-inflammatory *** main purpose is to promote their *** current aim of stem cell therapy is to replace the aged and metamorphosed cells in the ID and to increase the content of the extracellular *** treatment of disc degeneration with stem cells has achieved good efficacy,and the current challenge is how to improve this ***,we reviewed current treatments for disc degeneration and summarize studies on stem cell vesicles,enhancement of therapeutic effects when stem cells are mixed with related substances,and improvements in the efficacy of stem cell therapy by adjuvants under adverse *** reviewed the new approaches and ideas for stem cell treatment of disc degeneration in order to contribute to the development of new therapeutic approaches to meet current challenges.

关键词： Mesenchymal stem cells Intervertebral disc degeneration Extracellular vesicles Nucleus pulposus cells Tissue regeneration

Combination of ionic liquid dispersive liquid-phase microextraction and high performance liquid chromatography for the determination of triazine herbicides in water samples

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Chinese Chemical Letters 2014年第5期25卷 745-748页

作者： qing-xiang Zhou Yuan-Yuan Gao College of Geosciences China University of Petroleum Beijing College of Environmental Science and Engineering Nankai University

A temperature-controlled ionic liquid dispersive liquid-phase microextraction in combination with high performance liquid chromatography was developed for the enrichment and determination of triazine herbicides such as cyanazine,simazine,and atrazine in water samples.1-Octyl-3-methylimidazolium hexafluorophosphate（[C8MIM][PF6]） was selected as the extraction *** experimental parameters were *** the optimal conditions,the linear range for cyanazine was in the concentration range of 0.5–80 mg/L and the linear range for simazine and atrazine was in the range of1.0–100 mg/*** limit of detection（LOD,S/N = 3） was in the ranges of 0.05–0.06 mg/L,and the intra day and inter day precision（RSDs,n = 6） was in the ranges of 3.2%–6.6% and 4.8%–8.9%,*** real water samples were analyzed with the developed method,and the experimental results showed that the spiked recoveries were *** these exhibited that the developed method was a valuable tool for monitoring such pollutants.

关键词： Temperature-controlled ionic liquid dispersive liquid-phase microextraction Ionic liquid Triazine herbicides High performance liquid chromatography