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Journal of Integrative Plant Biology 2011年第1期53卷 35-43页

作者： cai-ling Wang Hai-ling Yang College of Life Sciences and Biotechnology Beijing Forestry University Beijing 100083 China

The tau class glutathione S-transferases （GSTs） have important roles in stress tolerance and the detoxification of herbicides in crops and weeds. Structural investigations of a wheat tau GST （TaGSTU4） show two subunit interactions： a hydrogen bond between the Tyr93 and Pro65 from another subunit of the dimer, and two salt bridges between residues Glu78 and side chains of Arg95 and Arg99 in the opposite subunit. By investigating enzyme activities, kinetic parameters and structural characterizations, this study showed the following results：（i） the hydrogen bond interaction between the Tyr93 and Pro65 was not essential for dimerization, but contributed to the enzyme＇s catalytic activity, thermal stability and affinity towards substrates glutathione and 1-chloro-2, 4-dinitrobenzene; and （ii） two salt bridges mainly contributed to the protein structure stability and catalysis. The results of this study form a structural and functional basis for rational design of more selective and environmentally friendly herbicides.

关键词： Herbicides Glutathione Stabling Salts Hydrogen Enzymes Hydrogenation Stability Brining Stables

Phenols/Al(C_(6)F_(5))_(3) Initiation Systems for Cationic Polymerizations of Isobutylene

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Chinese Journal of Polymer Science 2023年第5期41卷 713-719,I0008页

作者： ling cai Qi-Yuan Wang Xin-Li Liu Dong-Mei Cui State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Department of Polymer Science and Engineering University of Science and Technology of ChinaHefei 230026China

We report herein the cationic polymerization of isobutylene(IB)under mild conditions is realized with a new binary initiation system generated by simply mixing a Lewis super acid Al(C_(6)F_(5))_(3) and a substituted phenol(RPhOH).Polymers with medium and/or high molecular weights(M_(W)=4.9×10^(4)-27.7×10^(4) g·mol^(-1))can be obtained in toluene and temperatures from-20℃to 0℃.NMR spectrum analysis and DFT sim ulation reveals the in situ generated acidic coordinating complex Ak(C_(6)F_(5))_(3)·RPhOH is the initiating active species,which fu rther tran sformed into the ion-pair[Al(C_(6)F_(5))_(3)ORPh]^(-)[PIB]^(+)of the active intermediates upon growing IB monomers where the counter anion[Al(C_(6)F_(5))_(3)R^(O)Ph]-coordinates to the macrocation via the phenoxy *** catalyst performances are the concert effects of the steric bulkiness and electronics of the counter anion on the coordinating strength to the macrocation,which is significant to the stability of the active species.

关键词： Cationic polymerization Phenols Lewis super acid Polyisobutylene

Optimal control of differential quasivariational-hemivariational inequalities with applications

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Science China Mathematics 2024年第11期67卷 2587-2606页

作者： Dong-ling cai Stanislaw Migórski Yi-bin Xiao School of Mathematical Sciences University of Electronic Science and Technology of ChinaChengdu 611731China College of Applied Mathematics Chengdu University of Information TechnologyChengdu 610225China Chair of Optimization and Control Jagiellonian University in KrakowKrakow 30348Poland

In this paper,we study a new class of differential quasivariational-hemivariational inequalities of the elliptic *** problem consists of a system coupling the Cauchy problem for an ordinary differential equation with the variational-hemivariational inequalities,unilateral constraints,and history-dependent ***,based on the Minty formulation and the continuity of the solution map of a parametrized quasivariational-hemivariational inequality,and a fixed point theorem for a history-dependent operator,we prove a result on the ***,we examine optimal control problems for differential quasivariational-hemivariational inequalities,including a time-optimal control problem and a maximum stay control problem,for which we show the existence of *** all the optimal control problems,the system is controlled through a distributed and boundary control,a control in initial conditions,and a control that appears in history-dependent ***,we illustrate the results by considering a nonlinear controlled system for a time-dependent elliptic equation with unilateral constraints.

关键词： differential variational-hemivariational inequality unilateral constraint history-dependent operator optimal control time-optimal control maximum stay problem

Molecular Characterization of a Dehydroascorbate Reductase from Pinus bungeana

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Journal of Integrative Plant Biology 2009年第11期51卷 993-1001页

作者： Hai-ling Yang Ying-Ru Zhao cai-ling Wang Zhi-ling Yang Qing-Yin Zeng Hai Lu College of Life Sciences and Biotechnology Beijing Forestry University Beijing 100083 China State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany the Chinese Academy of Sciences Beijing 100093 China

Dehydroascorbate reductase （DHAR） plays a critical role in the ascorbate-glutathione recycling reaction for most higher plants. To date, studies on DHAR in higher plants have focused largely on Arabidopsis and agricultural plants, and there is virtually no information on the molecular characteristics of DHAR in gymnosperms. The present study reports the cloning and characteristics of a DHAR （PbDHAR） from a pine, Pinus bungeana Zucc. ex Endl. The PbDHAR gene encodes a protein of 215 amino acid residues with a calculated molecular mass of 24.26 kDa. The predicted 3-D structure of PbDHAR showed a typical glutathione S-transferase fold. Reverse transcripUon-polymerase chain reaction revealed that the PbDHAR was a constitutive expression gene in P. bungeana. The expression level of PbDHAR mRNA in P. bungeana seedlings did not show significant change under high temperature stress. The recombinant PbDHAR was overexpressed in Escherichia coil following purification with affinity chromatography. The recombinant PbDHAR exhibited enzymatic activity （19.84 ***/min per mg） and high affinity （a Krn of 0.08 mM） towards the substrates dehydroascorbate （DHA）. Moreover, the recombinant PbDHAR was a thermostable enzyme, and retained 77% of its initial activity at 55℃. The present study is the first to provide a detailed molecular characterization of the DHAR in P. bungeana.

关键词： cloning dehydroascorbate reductase enzyme activity gymnosperm.

Hydrothermal synthesis method of 5-(4'-methylbiphenyl-2-yl)-1H-tetrazole

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Chinese Chemical Letters 2013年第9期24卷 783-785页

作者： Wen-Xiang Wang Hong-ling cai Ren-Gen Xiong Ordered Matter Science Research Center Southeast University

A clean and saIe synthesis method of 5-（4＇-methylbiphenyl-2-yl）-1H-tetrazole was round： under hydrothermal conditions, 1.2 equiv, of 4＇-methylbiphenyl-2-carbonitrile react with 1 equiv, of sodium azide in a mixed solvent of propane-1,2-diol/H2O, with 1.5 equiv, of ammonium chloride and 0.2 equiv. of ammonium fluoride as catalyst. After simple post-processing, the yield can be improved to 95%, and the purity of the product is 99% without further recrystaUization.

关键词： Tetrazole Hydrothermal synthesis Propane-1 2-diol Sartan

Magnetism and Sound Velocities of Iron Carbide （Fe3C） under Pressure

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Chinese Journal of Chemical Physics 2014年第3期27卷 297-301页

作者： Zhao-yi Zeng Cui-e Hu Xun Liu ling-cang cai College of Physics and Electronic Engineering Chongqing Normal University Chongqing 400047China National Key Laboratory for Shock Wave and Detonation Physics Research Institute of Fluid Physics Chinese Academy of Engineering Physics Mianyang 521900 China Institute of Pulsed Power Science Kumamoto University Kurokami Kumamoto 860-8555 Japan

The elastic property and sound velocity of FeaC under high pressure are investigated by using the spin-polarized generalized gradient approximation within density-functional theory. It is found that the magnetic phase transition from the ground ferromagnetic （FM） state to the nonmagnetic （NM） state occurs at ～73 GPa. Based on the predicted Hugoniot of Fe3C, we calculate the sound velocities of FM-Fe3C and NM-Fe3C from elastic constants. Compared with pure iron, NM-FeaC provides a better match of compressional and shear sound velocities with the seismic data of the inner core, supporting carbon as one of the light elements in the inner core.

关键词： Alloy Sound velocity Density functional theory

A Computational Study on Water-assisted Ammonolysis of N-Methyl β-Sultam

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Chemical Research in Chinese Universities 2006年第1期22卷 94-98页

作者： HE Mao-xia FENG Da-cheng YU ling-juan cai Zheng-ting Institute of Theoretical Chemistry Shandong University Jinan 250100 P. R. China

The ring opening of β-sultam v/a an H2O-assisted ammonolysis process was studied by using Density Functional Theory（DFT） method at the B3LYP/6-31G level as a further step in the theoretical investigation of the ammonolysis reaction of β-sultams. The calculated pathways are analogous to those previously described for the non-assisted ammonolysis reaction. Solvent effects were assessed by using the polarized continuum model（PCM） method. The results show that mode 1 and pathway a in channel Ⅱ are the most favorable ones in both the cases. The energy barrier of the cleavage of C-S bonds producing P1 is the highest among all the energy barriers. The presence of a solvent in the continuum model disfavors the reaction, whereas the participation of water in the ammonolysis reaction plays a positive role and reduces the active energy greatly. The relative energies of all the transition states in the assisted ammonolysis are 20-80 kJ/mol lower than those for the non-assisted reaction.

关键词： Ammonolysis Water-assisted mechanism Density Functional Theory(DFT) β-Sultam

On Frankl and Fredi's Conjecture for 3-uniform Hypergraphs

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Acta Mathematicae Applicatae Sinica 2016年第1期32卷 95-112页

作者： Qing-song TANG Hao PENG cai-ling WANG Yue-jian PENG College of Sciences Northeastern University School of Mathematics Jilin University College of Mathematics Hunan University

Frankl and Füredi in [1] conjectured that the r-graph with m edges formed by taking the first m sets in the colex ordering of N^（r） has the largest Lagrangian of all r-graphs with m *** this r-graph by Cr,m and the Lagrangian of a hypergraph by λ（G）.In this paper,we first show that if（3^t-1） ≤m〈（3^t）,G is a left-compressed 3-graph with m edges and on vertex set[t],the triple with minimum colex ordering in G^c is（t — 2 — i）（t — 2）t,then λ（G） ≤λ（C3,m）.As an implication,the conjecture of Frankl and Fiiredi is true for（3^t）-6≤m≤（3^t）.

关键词： Colex ordering Lagrangians of r-graphs extremal problems in combinatorics

Ab initio Predictions of Structural and Thermodynamic Properties of Zr2AIC Under High Pressure and High Temperature

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Chinese Journal of Chemical Physics 2015年第3期28卷 263-268,I0001页

作者： Fen Luo Zhi-cheng Guo Xiu-lu Zhang Chang-ying Yuan ling-cang cai Laboratory for Extreme Conditions Matter Properties Southwest University of Science and Technol- ogy Mianyang 521900 China National Key Laboratory for Shock Wave and Detonation Physics Research Institute of Fluid Physics Chinese Academy of Engineering Physics Mianyang 521900 China

The structural and thermodynamic properties of Zr2A1C at high pressure and high temper- ature are investigated by first principles density functional theory method. The calculated lattice parameters of Zr2A1C are in good agreement with the available theoretical data. The pressure dependences of the elastic constants, bulk modulus, shear modulus, Young＇s mod- ulus, and Vickers hardness of Zr2A1C are successfully obtained. The elastic anisotropy is examined through the computation of the direction dependence of Young＇s modulus. By using the quasiharmonic Debye model, the thermodynamic properties including the Debye temperature, heat capacity, volume thermal expansion coefficient, and Griineisen parameter at high pressure and temperature are predicted for the first time.

关键词： Elastic property Thermodynamic property Density functional theory

Electronic and Optical Properties of Rock-Salt A1N under High Pressure via First-Principles Analysis

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Communications in Theoretical Physics 2008年第10期50卷 990-994页

作者： ZHANG Wei CHEN Xiang-Rong cai ling-Cang GOU Qing-Quan Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China International Centre for Materials Physics Chinese Academy of Sciences Shenyang 110016 China Laboratory for Shock Wave and Detonation Physics Research Institute of Fluid Physics Chinese Academy of Engineering Physics Mianyang 621900 China

Electronic and optical properties of rock-salt AIN under high pressure are investigated by first-principlesmethod based on the plane-wave basis *** of band structures suggests that the rock-salt AIN has an indirectgap of 4.53 eV,which is in good agreement with other *** investigating the effects of pressure on the energygap,the different movement of conduction band at X point below and above 22.5 GPa is *** opticalproperties including dielectric function,absorption,reflectivity,and refractive index are also calculated and *** found that the rock-salt AIN is transparent from the partially ultra-violet to the visible light area and hardly does thetransparence affected by the ***,the curve of optical spectrum will shift to high energy area (blueshift) with increasing pressure.

关键词： semiconductors electronic band structure optical properties density functional theory