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Journal of Materials Science & technology 2010年第7期26卷 584-588页

作者： Dongmei Ban,Ningsheng Xu,Shaozhi Deng,Jun Chen and Juncong She state key lab of Optoelectronic Materials and Technologies,Guangdong Province key laboratory of Display Material and technology,School of Physics and Engineering,Sun Yat-sen University,Guangzhou 510275,China state key lab of Optoelectronic Materials and Technologies Guangdong Province Key Laboratory of Display Material and Technology School of Physics and Engineering Sun Yat-sen University Guangzhou 510275 China

A simple method is introduced for the preparation of large-area films of molybdenum trioxide （MoO3） microbelts. It is found that such films can be grown on indium tin oxide （ITO） glasses or silicon substrates at low temperatures by thermal evaporation deposition in air without using catalyst. Field emission measurements show that the turn-on field of the MoO3 microbelts is as low as 2.2 V/μm required to obtain a current density of 10 μA/cm^2, The combination of the simplicity of the growth method and the attractive field emission performance makes it a potential low-cost technique for the preparation of large-area field emission cold cathode material.

关键词： Field emission Large-area film Molybdenum trioxide Microstructures and synthesis

Sintering and Phase Transformation of 7wt% Calcia-stabilized Zirconia Ceramics

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Journal of Wuhan University of technology(Materials Science) 2009年第2期24卷 304-307页

作者：陈常连 state key lab of Advanced technology for Materials Synthesis and Processing Wuhan University of Technology

Calcia stabilized zirconia（CSZ） ceramics were prepared with 7wt% calcia-stabilized zirconia powder by pressureless sintering technology. The crystal phases of the sintered samples were studied by X-ray diffraction（XRD） and Raman spectroscopy techniques, and the microstructures of the fracture surfaces were observed by scanning electron spectroscopy（SEM）. The phase compositions and the lattice parameters of cubic calcia-stabilized zirconia were calculated by XRD patterns. As the sintering temperature increasing from 1400℃ to 1600℃, the monoclinic zirconia content decreases gradually, finally all monoclinic phase transforms to cubic calcia-stabilized zirconia, which is deter- mined to be Ca0.134Zr0.866O1.866. It is revealed that monoclinic zirconia is the main factor causing minute cracks on the surface of sintered samples, and the combination of the XRD patterns and Raman spectra is an effective way to research the phase transformations of zirconia.

关键词： calcia-stabilized zirconia sintering phase transformation relative density

Large-scale Rock Landslide Slip Surface Location Analysis and Strength Parameters Evaluation

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Journal of Mountain Science 2011年第2期8卷 261-269页

作者： YOU Min NIE Dexin Civil Engineering School Anhui University of Architecture Hefei 230601 China Chengdu University of technology State Key Lab of Geo-hazards Prevention Chengdu 610059 China

Large-scale rock landslides have huge impacts on various large-scale rock engineering and project operations. They are also important aspects evaluating geological disasters. In the initial evaluations on the stability of large-scale rock landslides, in most cases, it is difficult to conduct evaluation or to have accurate evaluations because most of large-scale rock landslides are huge in size, high in slopes, and located in the canyon of mountains, which makes the exploration very difficult and thus hard to get credible data on slip surface form, location, depth and strength. This paper describes the Badi landslide happened along the Lancang River, and systematically introduces methods to analyze and verify large-scale slip surface form using terrain conditions surrounding the large-scale landslide, shape of the slide walls, and development patterns of streams and gully. This paper also introduces ways to obtain strength parameters of slip surface with the soil in the slide zone by using the principles of stress state, principles of gravity compaction, structure regeneration and strength regeneration. It is confirmed that analyzed results to the slip surface are basically consistent with the exploration results. The methods introduced here have been successfully applied to evaluate the stability of Badi large-scale rock landslide and have been applied in engineering practices.

关键词：滑坡稳定性强度参数评价位置岩石工程滑面滑动面项目运作

Thermodynamic Calculation of A_(r3) Temperature inLow Alloy Steels

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Journal of Materials Science & technology 1998年第4期14卷 380-382页

作者： Jinbo QU Zhenyu LIU Xianghua LIU and Guodong WANG (state key lab. of Rolling and Automation, Northeatern University Shenyang 110006, China) state key lab. of Rolling and Automation Northeastern University Shenyang 110006 China

On the basis of superelement model, Cahn's transformation kinetics theory and Scheil's additivity rule, actual γ/α transformation start temperature, A.3 in Fe-Σ Xi-C (Xi=Mn, Si, Ni, Mo etc.)multi-component low alloy Steels during continuous cooling process was calculated. Influences of chemical composition, hot deformation of γ and cooling rate on Ar3 temperature were analyzed. Calculated Ar3 temperatures are in reasonable agreement with measured ones.

关键词： Si Temperature inLow Alloy Steels Thermodynamic Calculation of A r3

INFLUENCE OF MIXING DEVICE ON SERUM-FREE CULTIVATION OF INSECT CELLS IN SPINNER FLASKS

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化工学报 2000年第S1期51卷 101-104页

作者： Zhao Jiao, Dai Hu and Tan Wensong (state key lab of Bioreactor Engineering, East China University of Science and technology Shanghai 200237,China)

A culture system was developed and successfully employed for the serum-free cultivation of Tn-5B1-4 (Tn5 ) insect cells. With our adaptation procedure, it was possible to obtain cells fully adapted to serum-free media in stationary T-flasks and then enable these adapted cells to grow well in spinner flasks immediately. The spinner "ask with special stirring design proved tO provide favorable culture environment that made it desirable for use in the serum-free cultivation of Tn5 cells even at low seeding density.

关键词： serum-free insect cells adaptation spinner flasks culture environment

Constrained oscillation of a bubble subjected to shock wave in microvessel

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Progress in Natural Science:Materials International 2009年第9期19卷 1109-1117页

作者： Farong Gao, Caihua Xiong *, Youlun Xiong Institute of Rehabilitation and Medical Robotics, state key lab of Digital Manufacturing Equipment and technology, School of Mechanical Science and Engineering, Huazhong University of Science and technology, Wuhan 430074, China Institute of Rehabilitation and Medical Robotics State Key Lab of Digital Manufacturing Equipment and Technology School of Mechanical Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China

A three-phase coupled model of the gasliquid-solid oscillation system is established to analyze the oscillation characteristics of a bubble inside a micro blood vessel with various radii and its shape changes with different interface boundaries. The results show that unlike the spherical symmetric oscillation in an unbounded fluid, the oscillating bubble has significant asymmetric characteristics under the constraint of a fiexible microvessel, especially while its radius reduces to the same order of magnitude as that of the bubble. Moreover, the variation of microbubble motion, whether the geometric shape or oscillation feature, exhibits obvious differences in the micro blood vessel compared with the rigid wall. The reasons behind these phenomena are analyzed in this paper. The conclusions have significant importance in the understanding of the mechanism of microvessel injury in ultrasound therapy.

关键词： Asymmetric oscillation Microbubble Shock wave Micro blood vessel Boundary effects

Fabrication of Homogenous Dispersion TiB_2-Al_2O_3 Composites

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Journal of Wuhan University of technology(Materials Science) 2011年第4期26卷 681-683页

作者：张金咏 state key lab of Advanced technology for Material Synthesis and Processing Wuhan University of Technology

In order to get a homogenous mixture and compact of TiB2-Al2O3, hybridization as a surface modification method was used to prepare nano-scale Al2O3 coated TiB2 particles. PE-wax particles were first coated onto TiB2 particles by hybridization, and then the nano-scale Al2O3 particles were coated onto the surface of TiB2 coated by PE-wax particles again. SEM, TEM and EDS were used to characterize the microstructure of as-received core/shell particles and its compacts. The experimental results show that a particle-scale homogenous dispersion of TiB2 and Al2O3 can be formed not only in mixed powder but also in dewaxed compacts. The compacts then were sintered by gas-pressing sintering （GPS）. Finial products show improved mechanic properties comparing with reference samples fabricated by normal ways.

关键词： TiB2/Al2O3 hybridization dispersion

Research on Ultrafine Tungsten Carbide-Cobalt(WC-Co) Cemented Carbide Rods of Miniature Drills for Highly Integrated Printed Circuit Board(PCB)

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Journal of Materials Science & technology 2005年第3期21卷 353-356页

作者： Xiaoliang SHI, Gangqin SHAO, Xinglong DUAN and Runzhang YUAN state key laboratory of Advanced technology for Materials Synthesis & Processing, Wuhan University of technology, Wuhan 430070, China lab. of Advanced technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan 430070 China

Nanocrystalline tungsten carbide-cobalt (WC-Co) composite powders produced through spray thermal decomposition-continuous reduction and carburization technology were used to prepare φ3.25 mm×38 mm ultrafine tungsten carbide-cobalt (WC-Co) cemented carbide rods through vacuum sintering plus sinterhip technology. The microstructure, Vickers hardness, density and Rockwell A hardness (HRA), transverse rupture strength (TRS), saturated magnetization and coercivity force were tested. The results show that the average grain size of the sintering body prepared through vacuum sintering plus sinterhip technology was 430 nm; transverse rupture strength (TRS) was 3850 MPa; Vickers hardness was 1890 and Rockwell A hardness of sintering body was 93. High strength and high hardness ultrafine WC-Co cemented carbide rods used to manufacture printed circuit board (PCB) drills were obtained.

关键词： Nanocrystalline Composite powder Cemented carbide Rods

Phase evolutions of two kinds of co-precipitated indium-tin oxide pre-cursors by heat-treatment

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Rare Metals 2005年第2期24卷 146-150页

作者： CHENShuguang LIChenhui XIONGWeihao LIULangming WANGHui ZhnzhouSmelterGroupCo.Ltd. Zhuzhou412004China statekeylabforPlasticFormingSimulation＆DieandMouldtechnology HnazhongUniversityofScienceandTechnologyWuhan430074China／／ZhnzhouSmelterGroupCo.Ltd.Zhuzhou412004China statekeylabforPlasticFormingSimulation＆DieandMouldtechnology HnazhongUniversityofScienceandTechnologyWuhan430074China

Two kinds of indium-tin oxide (ITO) precursors, cubic indium hydroxide(In(OH)_3) and orthorhombic indium oxide hydroxide (InOOH), were prepared by a co-precipitationmethod. With the help of X-ray diffraction (XRD), thermo-gravimetric analysis (TGA) and differentialthermal analysis (DTA), phase evolutions from cubic In(OH)_3 and orthorhombic InOOH to cubic ITOsolid solution and rhombohedral ITO solid solution by heat-treatment had been comprehensivelyinvestigated. The transformation from cubic In(OH)_3 to cubic ITO solid solution started as low as150 deg C and ended at about 300 degC, and it exhibited an endothermic behavior. The transformationfrom orthorhombic InOOH to rhombohedral ITO solid solution started at 220 deg C and ended at about430 deg C. Moreover, this transformation was composed of two processes: the one was the dehydrationof InOOH exhibiting an endothermic behavior and the other was the transformation from dehydrationproducts to rhombohedral ITO solid solution exhibiting a strong exothermic behavior. RhombohedralITO solid solution was metastable in air and it would transform to cubic ITO solid solution byheat-treatment. The transformation from rhombohedral ITO solid solution to cubic ITO solid solutionstarted at 578 deg C and ended below 800 deg C, and it exhibited a weak exothermic behavior.

关键词： inorganic and nonmetallic materials crystal structure X-ray techniques indium-tin oxide

Effect of Grinding and Polishing on the Residual Stress and Bending Strength of a Silicon Nitride Ceramic

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Journal of Wuhan University of technology(Materials Science) 2005年第1期20卷 46-48页

作者：高玲 state key lab of Advanced technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

The residual stresses on the surface of the d ifferently ground and polished silicon nitride ceramics were measured using X-r ay diffraction and identified by *** effect of the residual stress on the be nding strength was *** investigations show that the grinding proces s can introduce subatantial tensile residual stresses up to 290MPa on the surfac e of silicon nitride ceramics,which has a significant effect on reducing the ben ding strength of the ceramics after ***,in comparison with the ceramic s with a rough surface,the ceramics with a mirror image surface may have a lower *** can smooth the residual *** we evaluate the qualit y of the ceramic components after grinding,we must take residual stress into con sideration. The grinding methods and grinding conditions must be carefully selec ted in order to get the favorite residual stress as well as the surface smoothne ss.

关键词： residual stress grinding bending strengt h ceramics