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Apparent Kinetics for Electrosynthesis Process of Chromic Acid

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Chemical Research in Chinese Universities 2009年第4期25卷 532-536页

作者： LI Cheng-wei wang Fu-an qi tao wang Rui-lin TANG xiao-hong ZHANG Yong-qiang Department of Chemistry Henan institute of Education Zhengzhou 450014 P. R. China College of Chemical Engineering Zhengzhou University Zhengzhou 450002 P. R. China Institute of Process Engineering Chinese Academy of Sciences Beijing 100080 P. R. China

A new green technique for producing chromic acid via an electrosynthesis method was *** kinetic experiments were carried out on the direct electrosynthesis reaction of chromic acid from sodium dichromate in a self-made electrosynthesis reactor with a multiple-unit metal oxides combination anode,a stainless steel cathode,and a reinforcing combination Nafion 324 cation exchange *** apparent kinetic data were experimentally measured at different reaction time under different reaction conditions by relating many essential cell processes and their interaction,as well as their synergistic effect to the whole electrochemical synthesis *** results show that the electrosynthesis reaction process follows a quasi-first-order reaction kinetic *** apparent kinetic model of the electrosynthesis reaction was established,and kinetic parameters were calculated.

关键词： Apparent kinetics Chromic acid Electrosynthesis method Kinetic model

Effect of Alloying Elements on Thermal Wear of Cast Hot-Forging Die Steels

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Journal of Iron and Steel Research International 2006年第5期13卷 53-59页

作者： wang Shu-qi CHEN Kang-min CUI xiang-hong JIANG qi-chuan hong Bian School of Materials Science and Engineering Jiangsu University Zhenjiang 212013 Jiangsu China School of Materials Science and Engineering Jilin University Changchun 130025 Jilin China

The effect of main alloying elements on thermal wear of cast hot-forging die steels was studied. The wear mechanism was discussed. The results show that alloying elements have significant influences on the thermal wear of cast hot-forging die steels. The wear rates decrease with an increase in chromium content from 3% to 4% and molybdenum content from 2% to 3%, respectively. With further increase of chromium and molybdenum contents, chromium slightly reduces the wear resistance and molybdenum severely deteriorates the wear resistance with high wear rate. Lower vanadium/carbon ratio （1.5-2.5） leads to a lower wear resistance with higher wear rate. With an increase in vanadium/carbon ratio, the wear resistance of the cast steel substantially increases. When vanadium/carbon ratio is 3, the wear rate reaches the lowest value. The predominant mechanism of thermal wear of cast hot-forging die steels are oxidation wear and fatigue delamination. The Fe2O3 and Fe3O4 or lumps of brittle wear debris are formed on the wear surface.

关键词： hot-forging die cast steel alloying element thermal wear mechanism

Synthesis and CDK2 kinase inhibitory activity of 7/7′-azaindirubin derivatives

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Chinese Chemical Letters 2010年第3期21卷 297-300页

作者： wang, Zhao Hui dong, Ying wang, tao Shang, Ming hong Hua, Wei Yi Yao, qi Zheng China Pharmaceut Univ Sch Pharm Nanjing 210009 Peoples R China China Pharmaceut Univ Dept Organ Chem Nanjing 210009 Peoples R China China Pharmaceut Univ Jiangsu Ctr Drug Screening Nanjing 210009 Peoples R China

A series of novel 7 -azaindirubin(1a-g) and 7-azaindirubin(2a,2c,2e and 2f) derivatives were designed and *** structures were characterized by ~1H NMR and MS spectroscopy as well as by elemental *** inhibitory properties against CDK2/cylinA were evaluated in *** contrast to indirubin,some of the described azaindirubins emerged as potent inhibitors of CDK2/cylinA and compound 2b had more potent *** tests also showed that nitrogen atom at 7-position of azaindirubi...

关键词： 7 -Azaindirubin 7-Azaindirubin Synthesis CDK2/cyclinA Inhibition

Quantitative Structure-activity Relationship of TIBO HIV-1 Inhibitors

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Chinese Journal of Structural Chemistry 2007年第8期26卷 889-896页

作者： LI xiao-hong ZHANG Rui-Zhou CHENG Xin-Lu YANG xiang-dong College of Science Henan University of Science and Technology Luoyang 471003 China Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China

Density functional theory （DFT） was used to calculate a set of molecular descriptors （properties） for 14 TIBO derivatives with anti-HIV activity. Principal component analysis （PCA） and hierarchical cluster analysis （HCA） were employed in order to reduce dimensionality and investigate which subset of variables should be more effective for classifying TIBO derivatives according to their degree of anti-HIV activity. The PCA showed that the EHOMO, μ, LogP, QA, QB and MR variables are responsible for the separation between compounds with higher and lower anti-HIV activity. The HCA results are similar to those obtained with PCA. By using the chemometric results, four synthetic compounds were analyzed through PCA and HCA and three of them are proposed as active molecules against HIV, which is consistent with the results of clinic experiments. The methodologies of PCA and HCA provide a reliable rule for classifying new TIBO derivatives with anti-HIV activity. The model obtained showed not only statistical significance but also predictive ability.

关键词： structure-activity relationship DFT PCA HCA

Effect of competitive crystal growth on microstructural characteristics of directionally solidified nickel-based single crystal superalloy

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China Foundry 2022年第2期19卷 109-116页

作者： Mang Xu xiao-qi Geng xiang-long Zhang Guo-huai Liu Ye wang Zhao-dong wang Jing-jie Guo State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China School of Materials Science and Engineering Harbin University of Science and TechnologyHarbin 150040China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

Directionally solidified single crystal superalloy test bars were prepared by the spiral grain selection *** microstructural evolution and orientation characteristics of the starter block and spiral part were studied,and the influence of the competitive growth of crystals on the microstructural characteristics was *** results show that the divergent grain groups,with small size and randomly oriented grains,appear at the bottom of the start block due to the chilling effect,which is an important area for competitive *** the height of the starter block increases,the primary dendrite spacing increases,and the grain density decreases;furthermore,the proportion of grains with an orientation deflection angle less than 10°gradually ***texture gradually becomes stronger as the height of the starter block increases,which indicates that the competitive growth of crystals gradually *** the initial stage of the crystal selection in the spiral part,the obstacle of adjacent grains and spiral passage is the main working *** grains located at the inner side of the front edge of the spiral passage have the growth *** single crystal screening process is achieved at about two-thirds of the spiral height,and the single crystal with the orientation deviation angle of 6.7°from the casting axis is prepared.

关键词： directional solidification Ni-based superalloy microstructural evolution spiral grain selector single crystal

Microstructure and properties of TiB_(2)-Ni coatings with different binder phase contents deposited by HVOF spray process

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Rare Metals 2022年第4期41卷 1385-1393页

作者： xiao Chen hong-tao wang Gang-Chang Ji xiao-Bo Bai Wei Fu School of Mechanical and Materials Engineering Jiujiang UniversityJiujiang 332005China

TiB_(2)–Ni coatings with different binder phase contents were sprayed on Q235 substrate by a high-velocity oxygen-fuel(HVOF)method using ball-milled *** microstructure,phase compositions,as well as thermal shock behavior,abrasive wear,and corrosion resistance to molten Al-12.07 wt%Si alloy performances of as-sprayed coatings were *** results show that the three TiB_(2)–Ni coatings structure is dense with low porosity,and the main phase compositions of the coatings are TiB_(2) and Ni similar to those of original *** coatings that have superior performance of thermal shock resistance have good bond to the substrate with no change in thick-ness and microstructure of ***,the coat-ings also have good durability in the molten Al-12.07 wt%Si after 60-h immersion *** the mass loss of Q235 steel is five times as much as that of TiB_(2)–50Ni coatings after abrasive wear test.

关键词： HVOF TiB_(2)-Ni Microstructure Abrasive wear Corrosion

Effect of Spine Motion on Mobility in Quadruped Running

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Chinese Journal of Mechanical Engineering 2014年第6期27卷 1150-1156页

作者： CHEN dongliang LIU qi dong Litao wang hong ZHANG Qun College of Mechanical and Electrical Engineering Harbin Engineering University

Most of current running quadruped robots have similar construction： a stiff body and four compliant legs. Many researches have indicated that the stiff body without spine motion is a main factor in limitation of robots’ mobility. Therefore, investigating spine motion is very important to build robots with better mobility. A planar quadruped robot is designed based on cheetahs’ morphology. There is a spinal driving joint in the body of the robot. When the spinal driving joint acts, the robot has spine motion; otherwise, the robot has not spine motion. Six group prototype experiments with the robot are carried out to study the effect of spine motion on mobility. In each group, there are two comparative experiments： the spinal driving joint acts in one experiment but does not in the other experiment. The results of the prototype experiments indicate that the average speeds of the robot with spine motion are 8.7%–15.9% larger than those of the robot without spine motion. Furthermore, a simplified sagittal plane model of quadruped mammals is introduced. The simplified model also has a spinal driving joint. Using a similar process as the prototype experiments, six group simulation experiments with the simplified model are conducted. The results of the simulation experiments show that the maximum rear leg horizontal thrusts of the simplified mode with spine motion are 68.2%–71.3% larger than those of the simplified mode without spine motion. Hence, it is found that spine motion can increase the average running speed and the intrinsic reason of speed increase is the improvement of the maximum rear leg horizontal thrust.

关键词： quadruped robot spinal driving joint spine motion mobility locomotion experiment

A united tension/compression asymmetry micro-mechanical model for nickel-base single-crystal alloys

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Journal of Iron and Steel Research International 2019年第6期26卷 621-630页

作者： Jian-feng xiao Hai-tao Cui hong-jian Zhang Wei-dong Wen Jiangsu Province Key Laboratory of Aerospace Power System State Key Laboratory of Mechanics and Control of Mechanical Structures College of Energy & Power Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 Jiangsu China

In recent years, the micro-deformation mechanisms of the tension/compression behavior for nickel-base single-crystal superalloys have been studied extensively and general agreements have been derived. Based on these researches, a new model called united tension/compression asymmetry micro-mechanical model (UTCAM) has been proposed, which can effectively estimate the initial yield strength of nickel-base single-crystal (SC) superalloys under different loading directions. Considering the combined effects of octahedral slip system and cubic slip system, slip control factor is introduced in the UTCAM to determine the type of the open slip system of nickel-base single-crystal superalloys during deformation, thus making this model cover a rather wide range of application. Furthermore, the UTCAM is applied to hot tension and compression tests of three typical nickel-base SC superalloys (PWA1480-593 ℃, RENE N4-760 ℃ and DD407-760 ℃). The predicted initial yield strengths of the nickel-base SC superalloys are in good agreement with the experimental results, and the UTCAM proves to be effective.

关键词： Nickel-base single-crystal superalloy Initial yield strength Tension compression asymmetry Micro/mechanical model

Tensile properties and fracture reliability of a glass-coated Co-based amorphous microwire

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International Journal of Minerals,Metallurgy and Materials 2014年第6期21卷 583-588页

作者： xiao-dong wang Huan wang hong-xian Shen Fa-xiang qin Da-wei Xing Jing-shun Liu dong-ming Chen Jian-fei Sun School of Materials Science and Engineering Harbin Institute of Technology 1D Nanomaterials Group National Institute for Material Science

Co68.15Fe4.35Si12.25B15.25 （at%） amorphous microwires with a smooth surface and a circular cross-section were fabricated by the glass-coated melt spinning method. Their mechanical properties were evaluated through tensile tests of the glass-coated amorphous mi-crowires, and their fracture reliability was estimated using two-and three-parameter Weibull analysis. X-ray diffraction and transmission electron microscopy results showed that these glass-coated Co-based microwires were mostly amorphous. The coated Co-based microwires exhibit a tensile strength of 1145 to 2457 MPa, with a mean value of 1727 MPa and a variance of 445 MPa. Weibull statistical analysis showed that the tensile two-parameter Weibull modulus of the amorphous microwires is 4.16 and the three-parameter Weibull modulus is 1.61 with a threshold value as high as 942 MPa. These results indicate that the fabricated microwires exhibit good tensile properties and fracture reliability, and thus appear to be good candidates for electronics reliability engineering applications.

关键词： cobalt alloys amorphous alloys glass fracture tensile testing