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Rare Metals 2010年第2期29卷 220-225页

作者： ZHANG Qian, ZHANG Boping, Li Haitao, and SHANG Pengpeng school of materials {2. and engineering, University of {2. and technology Beijing, Beijing 100083, china school of materials {2. and engineering University of Science and Technology Beijing Beijing China

Lead-free piezoelectric NaxK1-xNbO3（x = 0.3-0.8）（NKN） ceramics were fabricated by normal sintering at 1060°C for 2.*** and electrical properties of the ceramics were investigated with a special emphasis on the influence of Na *** grain size of the produced dense ceramic was decreased by increasing Na content.A discontinuous change in the space distance was found at the composition close to Na0.7K0.3NbO3 ceramic, which indicates the presence of a transitional composition between two different orthorhombic phases, which is similar to the behavior of morphotropic phase boundary（MPB） in NaxK1-xNbO3 *** MPB-like behavior contributes to the enhanced piezoelectric coefficient d33 of 12. pC/N, planar-mode electromechanical coupling coefficient kP of 2..6%, and dielectric constant εr of 703, respectively for the Na0.7K0.3NbO3 *** temperature TC and the transitional temperature TO-T from orthorhombic to tetragonal phase are observed at around 42.°C and 2.0°C, respectively.

关键词： lead-free piezoelectric ceramics NKN sintering morphotropic phase boundary(MPB)

The dust emission law in the wind erosion process on soil surface

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science china(Physics,Mechanics & Astronomy) 2009年第2期52卷 258-269页

作者： XING Mao1 & GUO LieJin2.1 Mining technology Institute, taiyuan University of technology, taiyuan 03002., china 2.State Key Laboratory of Multiphase Flow in Power engineering, Xi’an Jiaotong University, Xi’an 710049, china Mining technology Institute Taiyuan University of Technology Taiyuan China State Key Laboratory of Multiphase Flow in Power engineering Xi’an Jiaotong University Xi’an China

The dust emission models to date cannot describe the relation between the transport rate of different sized grains and their grain size composition in soil surface, so Aeolian grain transport on a soil-like bed composed of fine sand and silt powder was measured in a wind tunnel. Six types of soil-like beds with different silt fractions have been tested in this experiment. The mass flux profiles of silt dust and sand grains are much different due to their different motion modes. Analysis of the vertical distribution of the powder and sand grains reveals that for a given soil bed, the ratio of the horizontal dust flux to the horizontal sand flux is directly proportional to their mass ratio in the bed. The dust flux is closely linked to the sand flux by the bombardment mechanism. For a given wind velocity and grain size of the bed, the slopes of the vertical mass flux profiles of sand grains larger than 100 μm are nearly equal in a log-linear plot and the ratio between the fraction of transport rate of each size group to the whole transport rate and the mass fraction of each size group in the bed is a constant only dependent on grain size. With this law, the transport rate of dust and different sized grains can be related with the grain size composition in the soil surface.

关键词： wind erosion dust transport rate grain size

Effect of Fe metal on the growth of silicon oxide nanowires

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International Journal of Minerals,Metallurgy and materials 2009年第3期16卷 317-321页

作者： Wei-long Liu1), Shu-huei Hsieh1), Ching He Chen2., and Wen-jauh Chen3) 1) Department of materials science and {2., Formosa University, Yunlin 632. china Taipei 2. Department of materials {2., Pingtung University of science and technology, Pingtung 912. china Taipei 3) Graduate school of materials science, Yunlin University of science and technology, Yunlin 632. china Taipei Department of materials science and {2. Formosa University Yunlin 632 China Taipei Department of materials engineering Pingtung University of Science and Technology Pingtung 912 China Taipei Graduate school of materials {2. Yunlin University of Science and Technology Yunlin 632 China Taipei

Silicon oxide (SiOx) nanowires are generally grown on Si substrate under the catalysis of Au in N2.atmosphere at elevated temperatures. Because the price of Au metal is quite high, Fe metal is then used to replace a part of Au for catalyzing the growth of SiOx nanowires. The results show that the Fe film can be used as the diffusion barrier of Au. SiOx nanowires are grown on Au/Fe/Si substrate at 1030°C. Under the catalysis of Fe/Au, the efficiency for the growth of SiOx nanowires is promoted.

关键词： silicon oxide nanowires Au catalyst Fe substitution Si substrate

Development of Expert Controller for Plasma Spraying Process

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材料热处理学报 2004年第5B期25卷 783-786页

作者： LIChun-xu CHENKe-xuan LIHe-qi LIDe-wu EducationMinistryKeyLab.ofAdvancedProcessingtechnologyforNon-ferrousmaterials LanzhouUniversityofScience＆TechnologyLanzhouChina Collegeofmaterialsscienceand{2. LanzhouUniv.ofScience＆TechnologyLanzhouChina

Aiming at the plasma spraying process control, the control system model is developed on the basis of analyzing control parameters and coating properties and their correlation, and the corresponding control method and regulations are also given. With the developed expert controller for plasma spraying process, stable spraying can be realized using ordinary spraying powder and the coating of compaction, homogeneity and high bonding strength can be obtained.

关键词：等离子喷涂控制器粉末熔炼镀层厚度

Study on the isothermal oxidation behavior in air of Ti_(3)AlC_(2. sintered by hot pressing

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science china(Technological sciences) 2006年第5期49卷 513-520页

作者： XU Xuewen1, 2. LI Yangxian1, MEI Bingchu2. ZHU Jiaoqun2. LIU Heyan1 & QU Jingping1 1. school of Material science and {2., Hebei University of technology, Tianjin 300130, china 2. State Key Laboratory of Advanced technology for materials Synthesis and Processing, Wuhan Univer- sity of technology, Wuhan 430070, china school of Material science and {2. Hebei University of Technology Tianjin China State Key Laboratory of Advanced technology for materials Synthesis and Processing Wuhan University of Technology Wuhan China

The isothermal oxidation behavior at 900–1300°C for 2. h in air of bulk Ti3AlC2.with 2.8 wt% TiC sintered by means of hot pressing was investigated in the work. The isothermal oxidation behavior generally followed a parabolic rate law. The parabolic rate constants increased from 1.39×10[10] kg[2.·m[4]·s[1] at 900°C to 5.56×10[9] kg[2.·m[4]·s[1] at 1300°C. The calculated activation energy was 136.45 kJ/mol. It was demonstrated that Ti3AlC2.had excellent oxidation resistance due to the continuous, dense; adhesive protect scales consisted of a mass of α-Al2.3; a little of TiO2./or Al2.iO5. In principle, the oxide scale was grown by the inward diffusion of O[2.; the outward diffusion of Ti[4+]; Al[3+]. The rapid outward diffusion of cations usually resulted in the formation of cracks, gaps,; holes.

关键词： Ti3AlC2. oxidation behavior, kinetics.

Research on the Cutting Performance of Cubic Boron Nitride Tools

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厦门大学学报（自然科学版） 2002年第S1期41卷 3-4页

作者： ZHENG Xiao-hua 1,2. YU Qi-xun 1, LIN Jing 1, LU Ming 2. PANG Si-qin 1 (1. school of Mechanical engineering and Automation, Beijing Institute of {2., Beijing 100081, china 2. school of Mechanical engineering, taiyuan University of {2., taiyuan 03002., china)

There were only two kinds of superhard tool material at the past, i.e. diamond and cubic boron nitride (CBN). Manmade diamond and CBN are manufactured by the middle of 2.th century. Various manufacturing methods and manmade superhard materials were developed later. They were widely used in different industry and science areas. Recently, a new kind of superhard tool material, C 3N 4 coating film, had been developed. American physical scientists, A. M. Liu and M. L. Cohen, designed a new kind of inorganic compound C 3N 4 with the theory of molecule {2.. According to calculation, it can reach or even exceed the hardness of diamond, so material scientists and technique circles draw their attention to it. A high speed steel twist drill coated with C 3N 4 film is applied to the drilling hole process on steel workpiece in cutting tests, the tool life is increased greatly. When the C 3N 4 film is coated on the cemented carbide inserts, the cutting performance is improved, but is not good enough. The data of mechanical performance and cutting tests about this kind of new tool material is given in this paper, it shows that C 3N 4 has a promising future. The anti-wear ability of cutting tool increases sharply after C 3N 4 being coated on HSS tool. Coated HSS drill also has some benefit after being reground. The tool life prolongs after C 3N 4 being coated on cemented carbide inserts, but is not so long as that of C 3N 4 coated HSS tool. When machining PRCM with C 3N 4 thin-film coated cemented carbide tool, the cutting performance is poor and it is much better when machining PRCM with PCBN, PCD compound plates and CVD thick-film coated cutting tool. Some relative aspects need to be deeply discussed and researched, e.g. the existing coating techniques is not good enough and should be improved in the future, the film thickness should be optimized and try to find out the most effective value, the binding force and mutual effect between coated film and substrate need to be

关键词： ultrahard material carbon nitride cutting tools cutting performance

Syntheses of amphiphilic biodegradable copolymers of poly(ethyl ethylene phosphate) and poly(3-hydroxybutyrate) for drug delivery

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science china Chemistry 2009年第7期52卷 961-968页

作者： CHENG Jing1 & WANG Jun2.1 Department of Polymer science and engineering, University of science and technology of china, Hefei 2.002., china 2.Hefei National Laboratory for Physical sciences at Microscale, school of Life sciences, University of science and technology of china, Hefei 2.002., china Department of Polymer science and engineering University of Science and Technology of China Hefei China Hefei National Laboratory for Physical sciences at Microscale School of Life Sciences University of Science and Technology of China Hefei China

Biodegradable and amphiphilic triblock copolymers poly(ethyl ethylene phosphate)-poly(3-hydroxybutyrate)-poly(ethyl ethylene phosphate) (PEEP-b-PHB-b-PEEP) have been successfully synthesized through ring-opening polymerization. The structures are confirmed by gel permeation chromatography and NMR analyses. Crystallization investigated by X-ray diffraction reveals that the block copolymer with higher content of poly(ethyl ethylene phosphate) (PEEP) is more amorphous, showing decreased crystallizability. The obtained copolymers self-assemble into biodegradable nanoparticles with a coreshell micellar structure in aqueous solution, verified by the probe-based fluorescence measurements and transmission electronic microscopy (TEM) observation. The hydrophobic poly(3-hydroxybutyrate) (PHB) block serves as the core of the micelles and the micelles are stabilized by the hydrophilic PEEP block. The size and size distribution are related to the compositions of the copolymers. Paclitaxel (PTX) has been encapsulated into the micelles as a model drug and a sustained drug release from the micelles is observed. MTT assay also demonstrates that the block copolymers are biocompatible, rendering these copolymers attractive for drug delivery.

关键词： poly(3-hydroxybutyrate) polyphosphoester drug delivery polymeric nanoparticles

Influence of Pr Content on the Sructure and Giant Magnetoresistance of Pr_x(Co_(40)Ag_(60))_(100-x) Granular Films

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Journal of Wuhan University of technology(materials {2.) 2011年第1期26卷 1-3页

作者：成钢 school of materials {2. and engineering Guilin University of Electronic Technology Guangxi Key Laboratory of Information materials

Prx（Co40Ag60）100-x （x=0, 0.5, 1, 1.5, 2. 3） granular films have been prepared by DC magneto controlled sputtering method. The XRD data indicated that Pr element favors the （111） plane preferential orientation. Magnetic measurements indicate that the average size of magnetic particles decreases as Pr content increases. For relatively low addition of Pr to CoAg granular films, Pr element can enhance GMR value and a peak value of about -14.3% is obtained at x=1.

关键词： giant magnetoresistance granular films magnetic particle

Establishment of Optimal Blade Clearance of Stainless Steel Rolling-Cut Shear and Test of Shearing Force Parameters

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Journal of Iron and Steel Research International 2012年第9期19卷 52-61页

作者： MA Li-feng 1 , 2., HUANG Qing-xue 1 , HUANG Zhi-quan 1 , CHU Zhi-bing 1 , TIAN Ya-qin 1 ( 1.College of Material science and engineering , {2. University of science and technology , taiyuan 03002. , Shanxi , china 2.Superplastic and Plastic Research Institute , Jilin University , Changchun 13002. , Jilin , china ) College of Material science and engineering Taiyuan University of Science and Technology Taiyuan Shanxi China Superplastic and Plastic Research Institute Jilin University Changchun Jilin China

The purpose aims to improve the plate shearing section quality and metal yield by means of optimal blade clearance adjustment model of rolling-cut shear and accurate calculation of the maximum shearing force , as well as for the system optimization design , structure optimization design to provide important basis.A 3 500mm rolling shear of a large stainless steel factory was taken as the test object , and the blade clearance under different influence factors of the clearance value and the shearing section were *** optimized production accumulated data regression analysis and the rolling shear process of stainless steel shear *** test results show that the optimal blade clearance adjustment module is a comprehensive function , which include steel plate thickness , material , temperature and shear plate *** shear stress at starting stage with the relative penetration depth increases affected by the above factors , and the fracture peak decreases rapidly after being cut into the roll phase constant.

关键词： stainless steel rolling-cut shear blade clearance shearing force industrial test

Influence of Absolute Basicity and Capillary Porosity on Carbonation of Concrete

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Journal of Wuhan University of technology(materials {2.) 2010年第5期25卷 889-892页

作者：巴明芳 school of materials {2. and engineering Southeast University Jiangsu Key Lab of Construction materials

The single influence of capillary porosity and coupling effects of absolute basicity and capillary porosity on concrete carbonation were investigated. The experimental results showed that carbonation rate of concrete at a given absolute basicity （AB） increased moderately with the increase of the porosity ranging from 6.2. to 9.2.%, and increased rapidly with porosity from 9.2.% to 12.8%.The coupling effect mainly embodied in disappeared mutation point of capillary porosity, and the distributing regions of carbonation depth were clearly partitioned in the coupling influence of absolute basicity and capillary porosity. A design method on carbonation related durability of concrete based on the coupling effects was proposed.

关键词： absolute basicity capillary porosity coupling effects carbonation rate