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Evaluation of Stabilization Performances of Antioxidants in Poly(ether ether ketone)

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Chemical Research in Chinese Universities 2012年第5期28卷 907-911页

作者： ZHOU Zheng ZHOU fu-gui ZHANG Shu-ling MU Jian-xin YUE Xi-gui WANG gui-bin High Performance Plastics Engineering Research Center Ministry of EducationCollege of ChemistryJilin UniversityChangehun 130012P.R.China

Two types of antioxidants（a primary antioxidant and a secondary antioxidant） were used to improve the stability of poly（ether ether ketone）（PEEK）. The effects of the antioxidants on the properties of PEEK and the stabilization mechanism were investigated by some characterization methods, such as rheometer, thermogravimetric ana- lysis（TGA）, universal tester and electron spin resonance（ESR）. The results indicate that the efficiency of the phosphorous antioxidant（DS） in improving the stability of PEEK was better than that of the phenolic antioxidant（DN） in both melting stability and thermal stability, and the thermal stability of PEEK sample containing 0.07%（mass fraction） DS was the best among all the samples due to the decrease of the free radicals density, as proven by ESR measurement. Additionally, no obvious changes could be observed in mechanical properties of PEEK containing antioxidants compared to those of virgin PEEK.

关键词： Poly(ether ether ketone) Antioxidant Stability Mechanical property Radical

Nicotinic Acetylcholine Receptor Gene Family of the Pea Aphid,Acyrthosiphon pisum

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Journal of Integrative Agriculture 2013年第11期12卷 2083-2091页

作者： LIU Yi-peng LIN Ke-jian LIU Yang gui fu-rong WANG gui-rong State Key Laboratory for Biology of Plant Diseases and Insect Pests/Institute of Plant Protection Chinese Academy of Agricultural Sciences College of Plant Protection Yunnan Agricultural University

The nicotinic acetylcholine receptors （nAchRs） are cholinergic receptors that form ligand-gated ion channels by ifve subunits in insect and vertebrate nervous systems. The insect nAChR is the molecular target of a class of insecticides, neonicotinoids. Here, we identiifed and cloned 11 candidate nAChR subunit genes in Acyrthosiphon pisum using genome-based bioinformatics combined modern molecular techniques. Most A. pisum nAChRs including α1, α2, α3, α4, α6, α8, and β1 show highly sequence identities with the counterparts of other insects examined. Expression proifles analysis showed that all subunit genes were expressed in adult head. At least two subunits have alternative splicing that obviously increase A. pisum nicotinic receptor diversity. This study will be invaluable for exploring the molecular mechanisms of neonicotinoid-like insecticides in sucking pests, and for ultimately establishing the screening platform of novel insecticides.

关键词： Acyrthosiphon pisum nicotinic acetylcholine receptor alternative splicing expression profile

Reduction behavior and mechanism of Hongge vanadium titanomagnetite pellets by gas mixture of H2 and CO

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Journal of Iron and Steel Research International 2017年第1期24卷 34-42页

作者： Wei Li gui-qin fu Man-sheng Chu Miao-yong Zhu School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina

Hongge vanadium titanomagnetite（HVTM）pellets were reduced by H2-CO gas mixture for simulating the reduction processes of Midrex and HYL-III shaft *** influences of reduction temperature,ratio ofφ（H2）toφ（CO）,and pellet size on the reduction of HVTM pellets were evaluated in detail and the reduction reaction kinetics was *** results show that both the reduction degree and reduction rate can be improved with increasing the reduction temperature and the H2 content as well as decreasing the pellet *** rational reduction parameters are reduction temperature of 1050℃,ratio ofφ（H2）toφ（CO）of 2.5,and pellet diameter in the range of 8-11 *** these conditions（pellet diameter of 11mm）,final reduction degree of 95.51% is *** X-ray diffraction（XRD）pattern shows that the main phases of final reduced pellets under these conditions（pellet diameter of 11 mm）are reduced iron and *** peak intensity of reduced iron increases obviously with the increase in the reduction ***,relatively high reduction temperature promotes the migration and coarsening of metallic iron particles and improves the distribution of vanadium and chromium in the reduced iron,which is conducive to subsequent melting *** the early stage,the reduction process is controlled by interfacial chemical reaction and the apparent activation energy is 60.78kJ/*** reduction process is controlled by both interfacial chemical reaction and internal diffusion at the final stage,and the apparent activation energy is 30.54kJ/mol.

关键词： Hongge vanadium titanomagnetite Pellet Gas-based direct reduction Behavior and mechanism Kinetics

Design and Kinematic Analysis of a Novel Humanoid Robot Eye Using Pneumatic Artificial Muscles

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Journal of Bionic Engineering 2008年第3期5卷 264-270页

作者： Xuan-yin Wang Yang Zhang Xiao-jie fu gui-shan Xiang State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 P. R. China

This paper proposed a novel humanoid robot eye, which is driven by six Pneumatic Artificial Muscles （PAMs） and rotates with 3 Degree of Freedom （DOF）. The design of the mechanism and motion type of the robot eye are inspired by that of human eyes. The model of humanoid robot eye is established as a parallel mechanism, and the inverse-kinematic problem of this flexible tendons driving parallel system is solved by the analytical geometry method. As an extension, the simulation result for saccadic movement is presented under three conditions. The design and kinematic analysis of the prototype could be a sig- nificant step towards the goal of building an autonomous humanoid robot eye with the movement and especially the visual functions similar to that of human.

关键词： bionic robotics bio-inspiration humanoid robot eye air muscle inverse-kinematic

Comparative study of HFACS and the 24Model accident causation models

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Petroleum Science 2017年第3期14卷 570-578页

作者： gui fu Jia-Lin Cao Lin Zhou Yuan-Chi Xiang School of Resources and Safety Engineering China University of Mining and Technology (Beijing) Beijing 100083 China

A comparative study is conducted to compare the theory and application effect of two accident causation models, the human factors analysis and classification system（HFACS） and the accident causation ＂2-4＂ model（24 Model）, as well as to provide a reference for safety researchers and accident investigators to select an appropriate accident analysis method. The two models are compared in terms of their theoretical foundations, cause classifications, accident analysis processes, application ranges, and accident prevention strategies. A coal and gas outburst accident is then analyzed using both models, and the application results are compared. This study shows that both the 24 Model and HFACS have strong theoretical foundations, and they can each be applied in various domains. In addition, the cause classification in HFACS is more practical, and its accident analysis process is more convenient. On the other hand, the 24 Model includes external factors, which makes the cause analysis more systematic and comprehensive. Moreover, the 24 Model puts forward more corresponding measures to prevent accidents.

关键词： HFACS Accident causation "2-4" model Comparative study Unsafe acts External causes Coaland gas outburst accident

Effect of V–Ti Addition on Microstructure Evolution and Mechanical Properties of Hot-Rolled Transformation-Induced Plasticity Steel

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Acta Metallurgica Sinica(English Letters) 2019年第3期32卷 352-360页

作者： Hai-Cun Yu Zhao-Zhen Cai gui-Qin fu Miao-Yong Zhu School of Metallurgy Northeastern University

In order to reveal the effect of V–Ti addition on the microstructure evolution and the mechanical properties of hot-rolled transformation-induced plasticity(TRIP) steel, two steels with 0.072 V–0.051 Ti steel(Bear-V–Ti steel) and 0.001 V–0.001 Ti steel(Free-V–Ti steel) were designed, respectively, and the comparison analyses were carried out by performing thermodynamic calculation and an experiment. With the thermodynamic calculation, the critical annealing temperature of a large fraction of retained austenite(～51%) obtained via solute enrichment was determined, and an optimized quenching at 650 °C and tempering at 200 °C adopted on the as-hot-rolled steel. The results show that the V–Ti TRIP steel displays more optimum mechanical stability during the tensile deformation, since the fraction and the mechanical stability of retained austenite are improved and the microstructure is also ultrarefined by V–Ti alloy precipitation. The yield strength of Bear-V–Ti steel increases from 650 to 800 MPa, and the ductility reaches 37%, showing that the comprehensive mechanical properties are greatly improved.

关键词： Medium manganese steel Microstructure evolution Mechanical properties V–Ti

Ferrous methanesulfonate as an efficient and recyclable catalyst for chemoselective synthesis of 1,1-diacetate from aldehydes

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Chinese Chemical Letters 2009年第9期20卷 1034-1038页

作者： Min Wang gui fu Tian Zhi Guo Song Heng Jiang College of Chemistry and Chemical Engineering Bohai University Jinzhou 121000 China Center for Science & Technology Experiment OBohai UniversityJinzhou 121000 China Liaoning Shihua University Fushun 113001 China

Ferrous methanesulfonate catalysing the conversion of aromatic, heteroaromatic, unsaturated, and aliphatic aldehydes to 1,1- diacetates at room temperature under solvent-free condition has been developed. The catalytic activity of seventeen metal methanesulfonates was compared under the same condition, ferrous methanesufonate proved to be the best. It can be easily recovered and reused for several times without distinct deterioration in catalytic activity. During the competitive protection between a ketone and an aldehyde group with Ac20, 1,1-diacetate formed exclusively with the aldehyde group. 2009 Min Wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： 1,1-Diacetate Aldehyde Chemoselectivity Reusability

Effect of Cr_2O_3 addition on the oxidation induration mechanism of Hongge vanadium titanomagnetite pellets

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International Journal of Minerals,Metallurgy and Materials 2018年第4期25卷 391-398页

作者： Wei Li Nan Wang gui-qin fu Man-sheng Chu Miao-yong Zhu School of Metallurgy Northeastern University

As part of a research project to develop a novel clean smelting process for the comprehensive utilization of Hongge vanadium titanomagnetite（HVTM）, in this study, the effect of Cr2O3 addition on the oxidation induration mechanism of HVTM pellets（HVTMPs） was investigated in detail. The results showed that the compressive strength of the HVTMPs was greatly weakened by the Cr2O3 addition, mainly because of a substantial increase in the porosity of the HVTMPs. The Cr2O3 addition marginally affected the phase composition but greatly affected the microstructural changes of the HVTMPs. Increased amounts of Cr2O3 resulted in a decrease in the uniform distribution of the hematite grains and in an increase in the Fe–Cr solid solutions（Fe1.2Cr0.8O3 and Fe0.7Cr1.3O3） embedded in the hematite grains. Moreover, the compact hematite was destroyed by forming a dispersed structure and the hematite recrystallization was hindered during the oxidation induration, which adversely affected the compressive strength. On the basis of these results, a schematic was formulated to describe the oxidation induration mechanism with different amounts of added Cr2O3. This study provides theoretical and technical foundations for the effective production of HVTMPs and a reference for chromium-bearing minerals.

关键词： chromium Hongge vanadium titanomagnetite porosity oxidation induration microstructure

Cobalt Sulfate as a Recyclable Catalyst for Chemoselective Synthesis of Diacetates from Aldehydes

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Chemical Research in Chinese Universities 2009年第4期25卷 455-457页

作者： WANG Min TIAN gui-fu SONG Zhi-guo JIANG Heng College of Chemistry and Chemical Engineering Bohai University Jinzhou 121000 P. R. China Center for Science ＆ Technology Experiment Bohai University Jinzhou 121000 P. R. China College of Petrochemical Engineering Liaoning Shihua University Fushun 113001 P. R. China

A mild and efficient method for diacetylation reaction was developed,by which diacetate could be achieved through the reaction of aldehyde with acetic anhydride,in the presence of cobalt sulfate,with an admirable yiel... 详细信息

关键词： Diacetate Aldehyde Acetic anhydride Cobalt sulfate