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湖南大学学报（自然科学版） 2009年第S1期36卷 60-65页

作者： LV Chao1,JIANG Yun-tao2.ZHAO Jia-ning1(1.School of Municipal & Environmental Engineering,harbin Institute of Technology,harbin,Heilongjiang 150090,{2. 2.The Architectural Design and research Institute,harbin Institute of Technology,harbin,Heilongjiang 150090,{2.) School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China Architectural Design and research Institute Harbin Institute of Technology Harbin 150090 China

From the view of both objective and subjective factors,the indoor air quality(IAQ)evaluation was *** dioxide(CO2.and formaldehyde(HCHO)were selected as the typical contaminants of indoor air,and the evaluation method of logarithmic index was adopted as the evaluation means of *** the recommended limits(RL)of typical contaminants CO2.and HCHO were given through analysis and *** limits of CO2.and HCHO in Indoor Air Quality Standard of{3. or other existing standards probably correspond to the level of PD=2.(%).The result shows that the existing standards fail to meet the requirement of the definition of "acceptable indoor air quality",that is to say,less than 2.% of the people express *** PD=2.%,RL of CO2.and HCHO are 72.×10-6 and 0.068×10-6 respectively,which are stricter than the limits in the existing *** method proposed in this paper is applicable to 13.1%≤PD≤86.7%.

关键词： indoor air quality(IAQ) typical contaminants recommended limits(RL) evaluation method of logarithmic index percentage of dissatisfaction(PD)

Mechanism of laser beam welding for SiC_P/6063.l composite

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Rare Metals 2002年第2期21卷 123-126页

作者： NIU Jitai, ZHANG Deku, and JI GuojuanNational Key Laboratory of Advanced welding Production Technology, harbin Institute of Technology, harbin 150001,{3. harbin Institute of Technology National Key Laboratory of Advanced Welding Production Technology Harbin 150001

The laser beam welding technique was used to process SiCparticles/6063.l alloy matrix composite, the in- fluence of laserpower and welding speed on the properties of joint was *** the laser beam power with same welding speed can make thequantity and size of Al_4C_3.decreased, and the ineractive mechanismof the reinforcing particles and the matrix in the joint and thecauses for joint strength reduction were analyzed. Increasing weldingspeed properly can improve the distribution of energy and restrainthe interfacial reaction in the molten pool, an measures for impovingwere proposed.

关键词： laser beam welding SiC_p joint interfacial

Numerical Simulation of Brazing TiC Cermet to Iron with TiZrNiCu Filler Metal

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Journal of Materials Science & Technology 2004年第3期20卷 261-264页

作者： Lixia ZHANG Jicai FENG National Key Laboratory of Advanced welding Production Technology,harbin Institute of Technology,harbin 150001,{3. Lab. of Adv. welding Technol. Harbin Inst. of Technol. Harbin 150001 China

The maximum thermal stress and stress concentration zones of iron/TiC cermet joint during cooling were studied inthis paper. The results showed that the shear stress on iron/TiC cermet joint concentrates on the interface tip andthe maximum shear stress appears on the left tip of iron/TiZrNiCu interface. Positive tensile stress on TiC cermetundersurface concentrates on both sides of TiC cermet and its value decreases during cooling. Negative tensile stresson TiC cermet undersurface concentrates on the center of TiC cermet and its value increases during cooling. Brazingtemperature has little effect on the development and maximum thermal stress.

关键词： Numerical simulation Brazing TiC cermet Iron

A New Model of Interfacial Physical Contact in Diffusion Bonding

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Journal of Materials Science & Technology 2004年第1期20卷 109-112页

作者： Peng HE, Jicai FENG and Yiyu QIANNational Key Laboratory of Advanced welding Production Technology, harbin Institute of Technology, harbin 150001,{3. Lab. of Adv. welding Technol. Harbin Inst. of Technol. Harbin 150001 China

Through eliminating voids not affecting the primary bonding process, and incorporating interlayer and flexible base material, the interface geometry character and brief mathematics process were put forth. Through analyzing contact process of diffusion bonding, contact area model was settled. It can interpret the phenomenon of different interface areas taking on different strengths. In the course of physical contact, shear stresses serve an important function for the plastic deformation and the cohesion of interface voids.

关键词： Diffusion bonding Physical contact Interface layer

Study on Environmental Multi-parameter Sensor Based on MEMS

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稀有金属材料与工程 2006年第S3期 377-380页

作者： Hongquan Zhang~(1,3. Tong Zhang~2.Likai Sun~3.Yunbo Shi~3.Jianying Guo~1 (1.harbin University of Science and Technology,harbin {2.,china) (2.Automobile Electronic Engineering Technology research and Development Center,harbin 150001,china) (3.Northeast Transducer Technology research Institute,harbin 150001,china)

A new membrane type Al2.3.icromachining material is *** develop an environmental multi-parameter detection micro-system,which implements the detection to temperature,humidity,wind speed,and *** test results illustrate that the heat-release unit in micro-system intercross greatly affects other sensing units on the *** study the method of etching process,which formed cavity to reduce the heat exchange efficiency and decrease temperature intercross effect.

关键词： Al2.3.membrane sensing unit environmental multi-parameter microsystem

Al2.3.Al2.3.Joint Brazed with Al2.3.particulate-contained Composite Ag-Cu-Ti Filler Material

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Journal of Materials Science & Technology 2005年第5期21卷 782-784页

作者： Jianguo YANG Hongyuan FANG and Xin WANState Key Laboratory of Advanced welding Production Technology, harbin Institute of Technology, harbin 150001,{3. State Key Laboratory of Advanced welding Production Technology Harbin Institute of Technology Harbin 150001 China

Microstructure and interracial reactions of Al2.3.joints brazed with Al2.3.particulate-contained composite Ag-Cu-Ti filler material were researched by scanning electron microscopy （SEM）, electron probe microscopy analysis （EPMA）, energy dispersive spectroscopy （EDS） and X-ray diffraction （XRD）. The interracial reaction layer thickness of joints brazed with conventional active filler metal and active composite filler materials with different volume fraction of Al2.3.particulate was also studied. The experimental results indicated although there were Al2.3.particulates added into active filler metals, the time dependence of interracial layer growth of joints brazed with active composite filler material is t^1/2.as described by Fickian law as the joints brazed with conventional active filler metal.

关键词： Composite filler materials Braze Interface Al2.3

Effects of Al2.3.Particulates on the Thickness of Reaction Layer of Al2.3.Joints Brazed with Al2.3.Particulate-Contained Composite Filler Materials

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Journal of Materials Science & Technology 2003年第5期19卷 509-510页

作者： Jianguo YANG, Jingwei WU and Hongyuan FANGNational Key Laboratory of Advanced welding Production Technology, harbin Institute of Technology, harbin 150001,{3. National Key Laboratory of Advanced welding Production Technology Harbin Institute of Technology Harbin 150001 China

In order to understand the rate-controlling process for the interfacial layer growth of brazing joints brazed with active composite filler materials, the thickness of brazing joints brazed with conventional active filler metal and active composite filler materials with different volume fraction of AI2.3.participate was studied. The experimental results indicate although there are Al2.3.particulates added into active filler metals, the time dependence of interfacial layer growth is t2.as described by Fickian law for the joints brazed with conventional active filler metal. It also shows that the key factor affecting the interfacial layer growth is the volume fraction of alumina in the composite filler material compared with the titanium weight fraction in the filler material.

关键词： Composite filler material Interfacial layer growth Brazing Ceramic

Distribution and characteristics of gravelly soil liquefaction in the Wenchuan M_s 8.0 earthquake

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Earthquake Engineering and Engineering Vibration 2010年第2期9卷 167-175页

作者： Cao Zhenzhong1,Hou Longqing2.Xu Hongmei2.and Yuan Xiaoming1 1. Institute of Engineering Mechanics,china Earthquake Administration,{3. {2.,china 2. East china Institute of Technology,Fuzhou 3.4000,china Institute of Engineering Mechanics China Earthquake Administration Harbin 150080 China

In this paper,a distribution map of gravelly soil liquefaction that was caused by the Wenchuan M8.0 earthquake in china is proposed based on a detailed field investigation and an analysis of geological soil profiles. The geological background of the earthquake disaster region is summarized by compiling geological cross sections and borehole logs. Meanwhile,four typical liquefied sites were selected to conduct sample drillings,dynamic penetration tests (DPT),and shear wave velocity tests,to understand the features of liquefied gravelly soil. One hundred and eighteen (118) liquefied sites were investigated shortly after the earthquake. The field investigation showed:(1) sandboils and waterspouts occurred extensively,involving thousands of miles of farmland,12. villages,eight schools and five factories,which caused damage to some rural houses,schools,manufacturing facilities and wells,etc.; (2. the Chengdu plain is covered by a gravelly soil layer with a thickness of 0 m to 541 m according to the geological cross sections; (3. there were 80 gravelly soil liquefied sites in the Chengdu plain,shaped as five belt areas that varied from 2. km to 40 km in length,and about ten gravelly soil liquefied sites distributed within Mianyang area; and (4) the grain sizes of the sampled soil were relative larger than the ejected soil on the ground,thus the type of liquefied soil cannot be determined by the ejected soil. The gravelly soil liquefied sites are helpful in enriching the global database of gravelly soil liquefaction and developing a corresponding evaluation method in further research efforts.

关键词： gravelly soil liquefaction borehole soil profile geological cross section grain size distribution Wenchuan earthquake

Influence of Surface Condition on Expulsion in Spot welding AZ3.B Magnesium Alloy

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Journal of Materials Science & Technology 2005年第5期21卷 749-752页

作者： Yarong WANG, Jicai FENG and Zhongdian ZHANGState Key Laboratory of Advanced welding Production Technology, harbin Institute of Technology, harbin 150001,{3. State Key Laboratory of Advanced welding Production Technology Harbin Institute of Technology Harbin 150001 China

Experiments were carried out to study the influence of surface condition on expulsion during the spot welding of AZ3.B Mg alloy. A general electrical contact resistance theory for conductive rough surfaces and the relation between maximum temperature Tm in the contact and voltage-drop V across interface of two surfaces were employed to understand the reason of expulsion in Mg alloy spot welding. The main reason of expulsion is that the high electrical contact resistance induced by large roughness of the surface and oxide film covered on the surface leads to local melting of metal in the interface of two surfaces, and liquid metal of the local area ejected from the specimen under electrode force forms expulsion.

关键词： Expulsion Magnesium alloy Spot-welding Electrical contact resistance