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Fabrication of sub-micro size PZT array and their ferroelectric properties

Science China(Technological Sciences) 2006年第6期49卷 693-700页

作者： ZHAO Gaoyang1, ZHANG Weihua1, XU Guomin1, DENG xiaocui1, JIANG Bailing1 & ZHAO Wei2.1. School of Materials Science and Engineering, xi’an University of Technology, xi’an 710048, China 2. xi’an Institute of Optics and Precision Mechanics of CAS, xi’an 710048, China School of Materials Science and Engineering Xi’an University of Technology Xi’an China xi’an Institute of Optics and Precision Mechanics of CAS Xi’an China

The photosensitive PZT sols and their gel films were prepared by sol-gel process. Based on the photosensitivity of the PZT gel films, two-dimensional (2.) array of the PZT gel film was fabricated using twice-exposure of double-beam interference on the gel film. PZT gel films coated on ITO/quartz substrate were exposed to an interference fringe of 32. He-Cd laser beams, the substrate was rotated by 90° between the first and second irradiation steps. Island type periodic 2. array structures with a pitch of 1 μm and cell size of about 480 nm × 480 nm × 40 nm were formed after the irradiation, and followed by leaching with organic solvent, and then by heat treatment at 600°C for 15 min. The hysteresis loops of the cell in PZT array were in-situ measured by the online-operation of TF analyzer and atomic force microscope (AFM). The probe can be located on the locked cell of PZT array in the AFM image. The alternating voltage applied to the locked cell is supplied by the TF analyzer through the conductive coating probe, and then the test signal is fed back to the TF analyzer to obtain the hysteresis loop of the locked cell of array in the absence of top electrode. The results show that the sub-micro size PZT arrays prepared in this way are of polarization reversal characteristics with the alternating electric fields, thereby exhibiting obvious ferroelectricity.

关键词： PZT, ferroelectric films, photosensitivity, hysteresis loop.

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Refractive index changes induced by sheet beams with various intensity distributions in LiNbO_(3):Fe crystal

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Science China(Physics,Mechanics & Astronomy) 2005年第4期48卷 399-412页

作者： ZHANG Peng1, ZHAO Jianlin1, XU Honglai1, SUN Yidong2. YANG Dexing1 & WANG Meirong1 1. Institute of Optical Information Science and Technology, School of Science, Northwestern Polytechnical University, xi’an 710072. China 2. School of Science, xi’an Jiaotong University, xi’an 710049, China Institute of Optical Information Science and Technology School of Science Northwestern Polytechnical University Xi’an China School of Science Xi’an Jiaotong University Xi’an China

According to the Kukhtarev equations and a simplified model based on the photovoltaic charge carriers transport mechanism, the distributions of the index changes (DICs) in LiNbO3:Fe crystals induced by sheet beams with various intensity profiles are theoretically analyzed. The numerically simulated results coincide with the analytic expressions deduced from the simplified model. The DICs in a LiNbO3:Fe crystal induced by sheet beams with rectangular, Gaussian and square law profiles are measured by using the interferometric method. By employing the analytic expressions, the experimental data points are well fitted. By utilizing the angular spectrum theory and the ray equation, the uniformities of the intensity profiles of the writing beams along the propagation directions and the influences of the self-defocusing effect of the crystal are numerically simulated, respectively. The results show that the experimental results are reliable. The numerically simulated method and the analytic expressions can be both employed to predict the DICs induced by sheet beams with various light intensity profiles. Furthermore, utilizing writing beams with proper intensity profiles, any desired index distributions could be obtained.

关键词： LiNbO3:Fe crystal, light intensity profile, distribution of refractive index changes, sheet beam.

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General inverse of Stokes, Vening-Meinesz and Molodensky formulae

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Science China Earth Sciences 2006年第5期49卷 499-504页

作者： CHENG Luying1,2.& XU Houze1 1. Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan 430077, China 2. xi’an Research Institute of Surveying and Mapping, xi’an 710054, China Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan China xi’an Research Institute of Surveying and Mapping Xi’an China

The operator operations between the disturbing potential and the geoidal undulation, the gravity anomaly, the deflection of the vertical are defined based on the relations among the gravity potential, the normal gravity potential and the disturbing potential. With the sphere as the boundary surface, based on the solution of the external boundary value problem for the disturbing potential by the spherical harmonics in the physical geodesy, the general inverse Stokes’ formula, the general inverse Vening-Meinesz formula and the general Molodensky’s formula are derived from the operator operations defined. The general formulae can get rid of the restriction of the classical formulae only used on the geoid. If the boundary surface is defined as the geoid, the general formulas are degen- erated into the classic ones.

关键词： spherical harmonics, boundary value problem, general inverse Stokes' formula, general inverse Vening-Meinesz formula, general Molodensky's formula.

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A Study on 3D FE Simulation Method of NC Bending Process of Thin-walled Tube

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厦门大学学报（自然科学版） 2002年第S1期41卷 73-74页

作者： ZHAN Mei 1, YANG He 1, JIANG Zhi-qiang 2. ZHAO Zhen-son g 1, LIN Yan 1 (1. College of Materials Science and Engineering, Northwestern Polytech nical University, xi’an 710072. China 2. xi’an Heavy Machinery Research Institute, xi’an 71003 2. China)

The numerical control (NC) precision bending process of thin-walled tube is on e of advanced plastic forming processes with high efficiency, forming precision, strength/weight ratio and low cost, thus it is playing more and more important role in manufacturing parts in aerospace and automobile industries. However, the determination of parameters crucial to make sure tube parts qualified is heavil y experience-based and involves repeated trial-and-errors in practice, which makes the production efficiency reduce drastically and does not fulfill the deve lopment of high technology. With quick development of computer technology and gr adual perfect of plastic forming theory, computer numerical simulation based on finite element method (FEM) has become one of important tools of researching and developing plastic forming technology. Development trend of NC precision bendin g process of tube is simulating its forming process by FEM. Because NC tube bend ing is of 3D nature, it is of great importance to analyze the forming mechanism and find out the influence law of forming parameters on forming process in the N C precision bending process of thin-walled tube quantitatively by 3D FE simulat ion. Based on the rigid-plastic finite element method (FEM) principle, a 3-dimens ional (3D) rigid-plastic FE simulation system named TBS -3D (tube bending simu lation by 3D FEM) for the NC bending process of thin-walled tube has been devel oped, a reasonable FEM model has been established. By use of this FEM simulation system, a NC bending process of thin-walled has been simulated. And deformed m eshes under different bending stages, stress distribution along bending directio n, relationship between maximal wall thickness changing ratio and bending angle have been obtained. And then some forming laws of NC tube bending obtained are a s follows: (1) NC bending process make tube elongate to some extent; (2. Charact eristic of stress distribution is that the outer area is undergoing tensil

关键词： tube forming NC bending process 3D FE simulatio n

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Combined adjustment project of national astronomical geodetic networks and 2.00' national GPS control network

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Progress in Natural Science:Materials International 2005年第5期15卷 435-441页

作者： YANG Yuanxi1*, ZHA Ming2. SONG Lijie3, WEI Ziqing1, WANG Zhouping2. OUYANG Guichong2. XU Bilin2. WU xiaoping3 and WANG Junqin4(1. xi'an Research Institute of Surveying and Mapping, xi'an 710054, China 2. xi'an Informational and Technical Center of Surveying and Mapping, xi'an 710054, China 3. Zhengzhou Institute of Surveying and Mapping, Zhengzhou 450052. China 4. The First Surveying Team of Tianjin, Tianjin 300140, China) xi'an Res. Inst. of Surveying and Mapping Xi'an 710054 China xi'an Info. and Technical Ctr. of Surveying and Mapping Xi'an 710054 China Zhengzhou Inst. of Surveying and Mapping Zhengzhou 450052 China First Surveying Team of Tianjin Tianjin 300140 China

The combined adjustment project of the nationwide astronomical geodetic networks and 2.00' national GPS control network involve 48519 terrestrial observational stations and 2.66 GPS observational stations. In the terrestrial network, 2.107 stations are height fixed and 2.412.stations are in three dimensions. 440793 terrestrial observations and 183668 unknowns are involved in the adjustment. The three-dimensional observational models for the adjustment have been established. The crustal deformation influences and corrections are researched. Fast methods of solving partitioned adjustment for super large-scale geodetic network have been studied. The standard deviations of three-dimensional coordinates for all stations are evaluated. As a result of the combined adjustment, a unified national geodetic network with nearly 50000 stations is established, the high accurate three-dimensional geocentric coordinates are obtained. The standard deviation for geoid is averagely 0.2.m, for vertical deflection is about 1.5″, for the horizontal position is about 0.12.m, for the geodetic height is about 0.14 m, and for the three-dimensional position is averagely 0.3 m.

关键词： astronomical geodetic network GPS network combined adjustment datum geocentric coordinates.

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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 2.ns （）3S1,2.nd（）3D（n=3-2.） of BeⅠ and 1sns（）3S1,1snd （）3D（n=3-2.） 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

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A New Nonlinear Compound Forecasting Method Based on ANN

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The Journal of China Universities of Posts and Telecommunications 2000年第3期7卷 74-80页

作者： JIANG Lin 1, xiE xiao yan 2. GAO De yuan 1 (1. Northwestern Polytechnical University, xian 710072.P.R.China 2. xian Institute of Posts and Telecommunications, xian 710061, P.R.China) Northwestern Polytechnical University Xi'an 710072 P.R.China xi'an Institute of Posts and Telecommunications Xi'an 710061 P. R. China

In this paper the compound forecasting method is discussed. The compound forecasting method is one of the hotspots in the current predication. Firstly, the compound forecasting method is introduced and various existing compound forecasting methods are discussed. Secondly, the Artificial Neural Network( ANN ) is brought in compound prediction research and a nonlinear compound prediction model based on ANN is presented. Finally, in order to avoid irregular weight, a new method is presented which uses principal component analyses to increase the availability of compound forecasting information. Higher forecasting precision is achieved in practice.

关键词： compound forecasting ANN Principal Component Analysis( PCA )

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A New ATM Self-Healing Algorithm with Back-Routing Capacity

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The Journal of China Universities of Posts and Telecommunications 2001年第3期8卷 11-16页

作者： ZHAO Ji-hong 1,2. LI Zeng-zhi1, QU Hua2.( 1. xi’an Jiaotong University, xi’an 7100, P.R.China 2. xi’an Institute to Posts and Telecommunications, xi’an 710061,P.R.China) xi'an Jiaotong University xi'an Institute to Posts and Telecommunications xi'an Jiaotong University xi'an Institute to Posts and Telecommunications

The self-healing mechanism of ATM networks is one of the key techniques for ensuring the network survivability. Based on the consideration of the future development of ATM networks and the limitation of the former various algorithms, this paper proposed a new self-healing algorithm for ATM networks: back-routing self-healing back-routing self-healing. First, we show the basic principles about our scheme. Next, we give the concept of back-routing self-healing algorithm. Finally, we analyze the new mechanism and confirm the effectiveness and feasibility of the proposed scheme.

关键词： self-healing fault restoration survivability network management

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The Dilution/Crystallization Kinetics of RDX and HMX

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含能材料 2002年第3期10卷 100-103页

作者： HU Rongzu1, LI Zhibin2. CHEN xijün2. GAO Shengli1, FANG Yan1, SHI Qizhen1(1. Department of Chemistry, Northwest University, xi′an 710069, China 2. xi′an Modern Chemistry Research Institute, xi′an 710065, China) Department of Chemistry Northwest University Xi'an 710069 xi'an Modern Chemistry Research Institute Xi'an 710065

Three thermokinetic equations describing the crystal growth process and two relationships between the parameters and the constants of the kinetic equations are derived. The thermokinetic data of crystal growth processes of RDX and HMX are treated based on the derived equations and relationships. The results show that the exothermic dilution / crystallization processes of RDX and HMX are the first order reaction and accord with the dislocation theory.

关键词：位错理论结晶动力学晶体生长

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Construction of expression vector for NT4-ADNF-9 fusion gene

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Journal of Pharmaceutical Analysis 2009年第2期21卷 104-108页

作者： Guo-xi Zheng1,Kang Zhu1,Yang Jing1,Jun-rong Wei1,Hong-liang Zhu2.. Department of Otorhinolaryngology,the Second Affiliated Hospital,Medical School of xi’an Jiaotong University,xi’an 710004 2. Medical School of xi’an Jiaotong University,xi’an 710061,China. Department of Otorhinolaryngology Second Affiliated Hospital Medical School of Xi'an Jiao-tong University Xi'an 710004 China Medical School of xi'an Jiaotong University Xi'an 710061 China

Objective To construct the prokaryotic expression vector bearing fusion gene NT4-ADNF-9 and lay foundation for further study on genetic therapy of neurosensory deafness. Methods By means of asymmetrical primer/ template,double stranded cDNA of activity dependent neurotrophic factor-9 (ADNF-9) was obtained,which included restriction enzymes sites on the two extremities. ADNF-9 cDNA was ligated to the signal and leader peptides of neurotrophin 4 (NT4),and the fusion gene was named NT4-ADNF-9. Then it was subcloned into prokaryotic expression vector pBV2.0,and called pBV2.0/ NT4-ADNF-9. Results Evidences of DNA sequence analysis and restriction enzymes digestion showed that we recombined ADNF-9 cDNA to the 3’terminal of the signal and leader peptides of NT4,and the fusion gene was subcloned into pBV2.0 successfully. Bioactivity of the products was proved that it could support the cell survival and neurite growth in the primary cultures of dorsal root ganglia (DRG) of embryonic day-8 chicken neurons as compared to the control. Conclusion Prokaryotic expression vector pBV2.0/NT4-ADNF-9 can be constructed successfully and the bioactivity is satisfactory.

关键词： activity dependent neurotrophic factor-9 neurotrophin 4 prokaryotic expression vector

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