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Triangular Halogen Bond and Hydrogen Bond Supramolecular Complex Consisting of Carbon Tetrabromide, Halide, and Solvent Molecule： A Theoretical and Spectroscopic Study

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Chinese Journal of Chemical Physics 2014年第3期27卷 265-273页

作者： Yu-jie Wu Xiao-ran Zhao hai-yue gao Wei-jun Jin College of Chemistry Beijing Normal University Beijing 100875 China

The theoretical calculation and spectroscopic experiments indicate a kind of triangular three bonding supramolecular complexes CBr4…X^-…-H-C, which consist of carbon tetrabromide, halide, and protic solvent molecule （referring to dichloromethane, chloroform and acetonitrile）, can be formed in solution. The strength of halogen and hydrogen bonds in the triangular complexes using halide as common acceptor obeys the order of iodide〉bromide〉chloride. The halogen and hydrogen bonds work weak-cooperatively. Charge transfer bands of halogen bonding complexes between CBra and halide are observed in UV-Vis absorption spectroscopy in three solvents, and then the stoichiometry of 1：1, formation constants K and molar extinction coefficients ε of the halogen bonding complexes are obtained by Benesi-Hildebrand method. The K and ε show a dependence on the solvent dielectric constant and, on the whole, obey an order of iodide〉bromide〉chloride in the same solvents. Furthermore, the C-H vibrational frequencies of solvent molecules vary obviously with the addition of halide, which indicates the C-H…X- interaction. The experimental data indicate that the halogen bond and hydrogen bond coexist by sharing a common halide acceptor as predicted by calculation.

关键词： Halogen bond Hydrogen bond Halide Carbon tetrabromide Charge transfer

Effect of gradient temperature rolling process on promoting crack healing in Q500 heavy plates

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International Journal of Minerals,Metallurgy and Materials 2020年第3期27卷 354-361页

作者： Zhao-hai gao Wei Yu Xu Chen Bao-sheng Xie Qing-wu Cai Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China National Engineering Research Center of Advanced Rolling University of Science and Technology BeijingBeijing 100083China Hunan Valin Rolling Steel Sheet Co.Ltd LoudiHunan 417000China

To ensure the quality of heavy plate products as determined by ultrasonic inspection, it is necessary to effectively control defects such as cracks and shrinkage cavities in heavy plates. Generally, some defects such as large size cracks exist due to insufficient deformation in the center of traditionally rolled plates. Compared with the traditional rolling process, gradient temperature rolling(GTR) process can effectively increase deformation inside heavy plates. In this study, the effect of GTR on crack healing was analyzed through a comparison experiment with the uniform temperature rolling(UTR). The results show that the GTR process could increase the plastic strain inside the heavy plate and effectively promote the healing process of the preset cracks. The degrees of crack healing at the center and quarter thickness position of the steel plate via GTR were greater than twice those of the plate via UTR. The GTR process can significantly reduce the internal defects of heavy plates and improve the defect detection level of heavy plate products. Also, The GTR process results in the formation of new crystal grains in the crack region, which is crucial to crack healing.

关键词： heavy plates multilayer pack rolling crack healing behavior hot rolling process

The Theoretical Investigation and Analysis of High-Performance ZnO Double-Gate Double-Layer Insulator Thin-Film Transistors

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Chinese Physics Letters 2012年第1期29卷 235-237页

作者： gao hai-Xia HU Rong YANG Yin-Tang School of Microelectronics Xidian UniversityXi’an 710071

A novel structure of a ZnO thin-film transistor with a double-gate and double-layer insulator is proposed to improve device *** with the conventional ZnO thin-film transistor structure,the novel thinfilm transistor has a higher on-state current,steeper sub-threshold characteristics and a lower threshold voltage,owing to the double-gate and high-k *** on two-dimensional simulation,the potential channel distribution and the reasons for the improvement in performance are investigated.

关键词： transistor double structure

Static Force Analysis of Foot of Electrically Driven Heavy-Duty Six-Legged Robot under Tripod Gait

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Chinese Journal of Mechanical Engineering 2018年第4期31卷 58-72页

作者： Zhen Liu Hong-Chao Zhuang hai-Bo gao Zong-Quan Deng Liang Ding State Key Laboratory of Robotics and System Harbin Institute of Technology College of Mechanical Engineering Tianjin University of Technology and Education

The electrically driven six-legged robot with high carrying capacity is an indispensable equipment for planetary exploration, but it hinders its practicability because of its low efficiency of carrying energy. Meanwhile, its load capacity also affects its application range. To reduce the power consumption, increase the load to mass ratio, and improve the stability of robot, the relationship between the walking modes and the forces of feet under the tripod gait are researched for an electrically driven heavy-duty six-legged robot. Based on the configuration characteristics of electrically driven heavy-duty six-legged, the typical walking modes of robot are analyzed. The mathematical models of the normal forces of feet are respectively established under the tripod gait of typical walking modes. According to the MATLAB software, the variable tendency charts are respectively gained for the normal forces of feet. The walking experiments under the typical tripod gaits are implemented for the prototype of electrically driven heavy-duty six-legged robot. The variable tendencies of maximum normal forces of feet are acquired. The comparison results show that the theoretical and experimental data are in the same trend. The walking modes which are most available to realize the average force of distribution of each foot are confirmed. The proposed method of analyzing the relationship between the walking modes and the forces of feet can quickly determine the optimal walking mode and gait parameters under the average distribution of foot force, which is propitious to develop the excellent heavy-duty multi-legged robots with the lower power consumption, larger load to mass ratio, and higher stability.

关键词： Electrically driven Heavy-duty six-legged robot Tripod gait Force of foot Walking mode

An efficient PSP-based model for optimized cross-coupled MOSFETs in voltage controlled oscillator

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第3期14卷 205-213页

作者： Li-heng LOU Ling-ling SUN Jun LIU hai-jun gao Institute of VLSI Design Zhejiang University MOE Key Laboratory of RF Circuits and Systems Hangzhou Dianzi University

This paper proposes an efficient PSP-based model for cross-coupled metal-oxide-semiconductor field-effect transistors(MOSFETs) with optimized layout in the voltage controlled oscillator(VCO).The model employs a PSP charge model to characterize the bias-dependent extrinsic capacitance instead of numerical functions with strong *** simulation convergence is greatly improved by this *** original scheme is developed to extract the parameters of the PSP charge model based on S-parameters *** interconnection parasitics of the cross-coupled MOSFETs are modeled based on vector *** model is verified with an LC VCO design,and exhibits excellent convergence during *** results show improvements as high as 60.5% and 61.8% in simulation efficiency and accuracy,respectively,indicating that the proposed model better characterizes optimized cross-coupled MOSFETs in advanced radio frequency(RF) circuit design.

关键词： Layout optimizing Modeling PSP Charge model Cross-coupled Metal-oxide-semiconductor(MOS) Voltage controlled oscillator(VCO)

Asymmetric reduction of α-hydroxy aromatic ketones to chiral aryl vicinal diols using carrot enzymes system

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Chinese Chemical Letters 2012年第6期23卷 635-638页

作者： Xiang Liu Yi Wang hai Yan gao Jian He Xu a School of Chemical and Material Engineering Jiangnan University Wuxi 214122 China State Key Laboratory of Bioreactor Engineering East China University of Science and Technology Shanghai 200237 China

Asymmetric reduction of ct-hydroxy aromatic ketones was carded out by using carrot enzymes system, yielding corresponding chiral vicinal diols with special functional groups. The optimum reaction conditions were obtained after investigation of various influencing factors. Chiral aryl vicinal diols were produced with good yields and excellent enantiomeric excesses under appropriate conditions. Meanwhile, the steric factors and electronic effects of the substituents on the aromatic ring were shown to have an interesting influence on both yield and enantioselectivity.

关键词： Asymmetric reduction Chiral aryl vicinal diol Aromatic ketone Carrot cell

Effect of Sodium Ferulate on Myocardial Ischemia Fibrosis Induced by Isoproterenol

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Chemical Research in Chinese Universities 2009年第5期25卷 699-704页

作者： gao hai-cheng SUN Bo YU Xiao-yan gao hai-mei SHI Yan MIAO Chun-sheng LI Xiang-jun LUO Ping ZOU Ying-gang WEI hai-feng ZHAO Juan REN Li-qun School of Pharmacy Jilin University Changchun 130021 P. R. China The Second Clinical Hospital of Jilin University Changchun 130041 P. R. China

We examined whether the powerful sodium ferulate（SF） could improve myocardial ischemia fibrosis degree and gain the information of myocardial energy metabolism via experimental model of myocardial ischemia fibrosis. The model of myocardial ischemia fibrosis was made for the wistar rats induced with 15 mg/kg isoproterenol（Iso） subcutaneous injection. In experiment l, Iso effective model drug of myocardial ischemia fibrosis at present was administrated to the rats with myocardial ischemia fibrosis and 2, 4, 6, 12, 24, 48 and 72 h, 7 and 21 d later, the changes of adenosine content in rat myocardial tissue and hydroxyproline in blood serum were compared. In experiment 2, SF was administrated to the rats with myocardial ischemia fibrosis and 21 d later, the effect of SF on benazepril as reference drug curing myocardial ischemia fibrosis was evaluated by measuring the changes of adenosine in rat myocardial tissue and hydroxyproline content in blood serum. In the model group, there was a remarkable increase in hydroxyproline content and a decrease in adenosine content of myocardial tissue in experiment 1; there was a remarkable decrease in hydroxyproline in blood serum and a increase in adenosine content in myocardial tissue, which were recovered gradually to control in experiment 2（P〈0.05）. The results of experiment 1 show that with the increasing of pathological change degree, the rat adenosine content reduced gradually and arrived at the lowest value three weeks later（P〈0.05）; the hydroxyproline content was obviously higher compared with that of control group（P〈0.05）. The results of experiment 2 show that rat adenosine content in myocardial tissue and hydroxyproline content in blood serum were recovered gradually to normal level after injection SF. The effect of SF against myocardial ischemia fibrosis in preventive group is better than that of improving the myocardial ischemia fibrosis drug. Meanwhile, hinting HPLC is a good method to measure the adenosine content.

关键词： Energy metabolism Hydroxyproline Myocardial fibrosis HPLC

Norditerpenoid Alkaloids from Aconitum spicatum Stapf

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Journal of Integrative Plant Biology 2006年第3期48卷 364-369页

作者： Li-Ming gao hai-Yan Yan Yang-Qing He Xiao-Mei Wei Department of Chemistry Key Laboratory of Polymer Materials of Gansu Province Northwest Normal University Lanzhou 730070 China

To search for pharmacologically and structurally interesting substances from traditional Chinese medicines, we Investigated the chemical compounds of Aconitum spicatum Stapf. Two new nordlterpenold alkaloids, namely spicatlne A （compound 1） and splcatine B （compound 2）, as well as 11 known norditerpenoid alkaloids were Isolated from the CHCIs portion of the 90% ethanol extract of the roots of A. spicatum. The structures of the alkaloids were characterized on the basis of their spectral data. One of the Isolated compounds showed significant cytotoxic activities （IC50 values 〈 200μmol/l.） against the HL-60 cell line.

关键词： Aconitum spicatum cytotoxic activity norditerpenoid alkaloids spicatine A spicatine B.

Synthesis,Crystal Structure and Antitumor Activities of Ethyl 5-methyl-4-morpholino-2-(3-Methyl-phenylamino)-furo[2,3-d] pyrimidine-6-carboxylate

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Chinese Journal of Structural Chemistry 2013年第12期32卷 1868-1872页

作者： LI Yan TANG He-Xin gao hai-Tao HU Yang-Gen School of Nuclear Technology & Chemistry and Biology Hubei University of Science and Technology Institute of Synthetic Organic and Medicinal Chemistry Hubei University of Medicine Taihe Hospital of Hubei University of Medicine

The title compound （C21H24N4O4, Mr = 396.44） has been synthesized by the func- tionalized ethyl 4-chloro-6-methyl-2-arylamino-furo[2,3-d]pyrimidine-5-carboxylates and mor- pholine. Its structure was confirmed by means of 1H NMR IR, MS and elemental analysis. The crystal structure of the title compound was determined by X-ray single-crystal diffraction. The compound crystallizes in triclinic system, space group P1, a = 7.9919（8）, b = 9.9312（1）, c = 12.9380（13） A, aα = 86.987（2）, β = 83.604（2）, γ = 89.641（2）°, V = 1019.08（18） A3, Z = 2, F（000） = 420, Dc = 1.292 g/cm3,μ = 0.091 mm-1, R = 0.0602 and wR = 0.1548 for 3943 independent （Rint = 0.0639） and 3414 observed （I 〉 2σ（I）） reflections, lntermolecular N-H…O and π-π stacking interactions contributed to the stability of the structure. The preliminary biological test indicated the title compound exhibited cytotoxicity against human lung cancer cell lines.

关键词： furo[2,3-d]pyrimidine synthesis crystal structure antitumor activity