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Prestress Design of Stainless Steel Fibers/Zirconia Composite by Tape Casting

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Journal of Wuhan university of technology(Materials Science) 2010年第4期25卷 565-569页

作者：赵康 School of Materials and Engineering Xi'an University of Technology

Prestressed SUS316 fibers/ZrO2 composite was fabricated using tape casting. Causes of cracks were analyzed by classical thermo-elastic theory and finite element method in preparation process. An optimization design was carried out on SUS316 fibers’ arrangement modes by reducing residual thermal stress. Interface topography and element distribution of composite were observed, and bending strengths were tested. Results show that cracks are generated along the direction vertical to SUS316 fibers by axial thermal stress due to different thermal expansion coefficients between SUS316 fibers and zirconia, and the average cracking space is 2 mm. No macroscopic defect is found in composite with SUS316 fibers of sine distribution, and it has better interfacial binding force since interdiffusion between SUS316 and zirconia. Bending strengths of composite with 0°/0°lamination are anisotropic and that are 385.74 MPa and 500.7 MPa respectively, but that with 0°/90°lamination is isotropic and it is 433.92 MPa. Bending strength of composite is increased obviously compared with that of zirconia because the prestress of surface is compressive stress.

关键词： SUS316 fibers/ZrO2 prestress tape casting finite element bending strength

On Nonautonomous Prey-predator Patchy System

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Communications in Mathematical Research 1999年第1期 25-31页

作者： Ruan xiaoe (College of Science, xi’an Jiaotong university, xi’an, 710049) Chen Lansun (Institute of Mathematics, Academic Sinica, Beijing, 100080) Wang Jianguo (xi’an Architecture and technology university, xi’an, 710055)

§１．ＩｎｔｒｏｄｕｃｔｉｏｎＩｎｔｅｒｅｓｔｈａｓｂｅｅｎｇｒｏｗｉｎｇｉｎｔｈｅｓｔｕｄｙｏｆｍａｔｈｅｍａｔｉｃａｌｍｏｄｅｌｓｏｆｐｏｐｕｌａｔｉｏｎｓｄｉｓｐｅｒｓ－ｉｎｇａｍｏｎｇｐａｔｃｈｅｓｉｎａｈｅ... 详细信息

§１．ＩｎｔｒｏｄｕｃｔｉｏｎＩｎｔｅｒｅｓｔｈａｓｂｅｅｎｇｒｏｗｉｎｇｉｎｔｈｅｓｔｕｄｙｏｆｍａｔｈｅｍａｔｉｃａｌｍｏｄｅｌｓｏｆｐｏｐｕｌａｔｉｏｎｓｄｉｓｐｅｒｓ－ｉｎｇａｍｏｎｇｐａｔｃｈｅｓｉｎａｈｅｔｅｒｏｇｅｎｅｏｕｓｅｎｖｉｒｏ...

关键词： Permanence Periodic Solution Diffusion Asymptotically Stable

INSPIRING STUDENTS’INTEREST IN ENGLISH IN LISTENING CLASSES

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Chinese Journal of Applied Linguistics 2002年第2期25卷 24-26,63页

作者： Shi xiaomei xi’an university of technology

This paper discusses the contradicting situation between the limited class-hours and the higher demands for CET,esp listening and speaking;analyzes the major factors hindering the development of the students' listening and speaking skills according to a survey;and discusses some possible ways to inspire students' interests in English based on some of the attempts made by the author in her teaching reform in listening classes.

关键词：学习兴趣英语听力教学教学效果激发障碍因素中学生英语教学方法大学英语教师英语听力理解问卷调查

THE FLOW PATTERNS OF BUBBLE PLUME IN AN MBBR

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Journal of Hydrodynamics 2011年第4期23卷 510-515页

作者： LI Shi-rong CHENG Wen WANG Meng CHEN Chen Key Laboratory of Northwest Water Resources and Environmental Ecology of Ministry of Education Xi＇an University of Technology Xi＇an 710048 China Oil Production Plant of No. 4 Changqing Oilfield Company China National Petroleum Corporation Jing Bian 718500 China

The flow patterns of the gas-liquid two-phase flow in a Moving-Bed Biofilm Reactor （MBBR） have a critical effect upon the mass transfer by the convection. Bubble plumes promote unsteadily fluctuating two-phase flows during the aeration. This article studies the unsteady structure of bubble plumes through experiments. The time-serial bubble plume images in various cases of the tank are analyzed. The Recursive Cross Correlation-Particle Image Velocimetry （RCC-PIV） is used to calculate the velocities in those cases, and then the time-serial vortex, the total turbulence intensity, the time-serial streamline are obtained. It is shown that the aspect ratio and the void fraction are the dominant factors influencing the unsteady structure of bubble plumes. When the aspect ratio is unity and the void fraction is high, the bubble plumes see a symmetrical vortex structure with a long residence time, which is beneficial for optimizing the aeration system and enhancing the applied range of bubble plumes.

关键词： bubble plume Recursive Cross Correlation (RCC) Particle Image Velocimetry (PIV) flow pattern

Radiative lifetimes of Rydberg states of BeⅠand BeⅢ

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原子与分子物理学报 2003年第4期20卷 575-578页

作者： LIANG Liang~(1,2), WANG Yong-chang~1 (1. Institute of modern Physics, School of science, xi’an Jiaotong university, xi’an 710049, P. R. China 2. Department of Physics, xi’an university of Architecture and technology, xi’an 710055, P. R. China) Institute of moderm Physics School of scienceXi'an Jiaotong University Xi'an 710049

By using the multichannel quantum defect theory （MQDT）, we have evaluated the energy levels and lifetimes of 2sns （）3S1,2snd（）3D（n=3-25） of BeⅠ and 1sns（）3S1,1snd （）3D（n=3-25） of BeⅢ. These energies and lifetimes that we have calculated not only agree with the recent measurements and theoretical calculation of Ref.4 and Ref.3, but also predict the lifetimes of 66 other highly excited states.

关键词：辐射寿命里德伯态多道量子缺陷理论铍元素原子高激发态原子物理学

Mechanism of Combustion Synthesis of TiC-Ti Cermet

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Journal of Wuhan university of technology(Materials Science) 2007年第3期22卷 502-505页

作者：肖国庆 School of Materials Science and Engineering Xi’an University of Architecture and Technology

In order to investigate the mechanism of combustion synthesis of TiC-Ti cermet, a mixture of Ti and C was used for a combustion front quenching test, and the microstructural evolution in the quenched sample was analyzed by scanning electron microscopy （SEM） and energy dispersive X-ray （EDX）. Also, a temperature-time profile of the combustion reaction was measured. Based on the experimental results, a reaction-dissolution-precipitation mechanism of the combustion synthesis of TiC-Ti was proposed.

关键词： TiC-Ti cermet combustion synthesis combustion front quenching method

具有随机寿命的多维Black-Scholes定价模型

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系统工程理论与实践 2004年第8期24卷 44-48页

作者：薛红西安工程科技学院理学院陕西西安710048

　利用随机微分方程和鞅方法,给出了具有随机寿命的多维Black-Scholes定价模型,并获得随机寿命情形下欧式期权及其它未定权益定价的解析表达式.将Black-Scholes定价模型进行了更为合理地推广.

关键词：随机微分方程鞅方法 Black—Scholes定价模型未定权益

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塔架交叉斜杆考虑屈曲相关性的稳定承载力

土木工程学报 2011年第1期44卷 19-28页

作者：陈绍蕃西安建筑科技大学陕西西安710055

单角钢交叉斜杆是塔架结构常用的部件。由于构造关系,杆端不仅有力的偏心,还有转动约束,偏心情况又随构造而异,使受压斜杆稳定计算十分复杂。现行输电塔架的技术标准都把它简化为轴心受压杆件来算,但方法比较粗略,可靠度不均衡。本文依... 详细信息

单角钢交叉斜杆是塔架结构常用的部件。由于构造关系,杆端不仅有力的偏心,还有转动约束,偏心情况又随构造而异,使受压斜杆稳定计算十分复杂。现行输电塔架的技术标准都把它简化为轴心受压杆件来算,但方法比较粗略,可靠度不均衡。本文依据弹性稳定理论,考虑屈曲时构件的相关性,并结合具体构造进行分析,得出精度和可靠度比较好的实用计算公式。建议方法的特点之一是对连接于单角钢主杆的交叉斜杆和连接于十字形双角钢主杆的交叉斜杆区别对待,特点之二是具体考虑杆与杆之间和杆段与杆段之间的相关关系,提出的计算公式和试验资料符合较好。文中还讨论了对单角钢斜杆限制其宽厚比的意义和超限杆承载力计算,以及杆端连接螺栓数量对承载力的影响。

关键词：输电塔交叉斜杆相关屈曲单角钢压杆

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平面对称标量场产生的引力孤波

物理学报 1997年第4期46卷 640-644页

作者：强稳朝西安建筑科技大学基础部

求出了平面对称零质量标量场产生的一组引力孤波解。

关键词：标量场经力孤波广义相对论