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|m| Partial wave treatment for two-dimensional Coulomb-scattering and Regge pole

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Science china(Physics,Mechanics & Astronomy) 2004年第6期47卷 676-684页

作者： wang Jing & ZENG Jinyan Department of Physics,tsinghua university,{2.,china School of Physics,Peking university,beijing 100871,china Department of Physics Tsinghua University Beijing 100084 China School of Physics Peking University Beijing 100871 China

The symmetry and |m| partial-wave analysis for two-dimensional (2.) Coulomb-scattering is investigated. As a function of energyE, the |m| partial-wave scattering amplitudef |m|(θ) is analytically continuated to the, negativeE (complexk) plane, and it is found that the bound state energy eigenvalues (E<0) are just located at the poles off |m|(θ) on the positive imaginaryk axis as is expected. In addition, as a function of |m|,f |m|(θ) is analytically continuated to the complex |m| plane, the bound state energy eigenvalues are just located at the poles off |m|(θ) on the positive real |m| axis.

关键词： two-dimensional Coulomb scattering, |m| partial-wave, Regge pole.

Transverse vibration of the blade for unmanned micro helicopter using rayleigh-ritz method

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Journal of university of Science and Technology beijing 2003年第6期10卷 40-43页

作者： Jungang Lii, Jiadao wang, and Darong ChenState Key Laboratory of Tribology, tsinghua university, {2., china Lab. of Tribology Tsinghua Univ. Beijing 100084 China

A rotor manipulation mechanism for micro unmanned helicopter utilizing the inertia and the elasticity of the rotor is introduced. The lagging motion equation of the rotor blades is established, and then the natural frequencies and mode shapes of the blade for the helicopter are studied by using beam characteristic orthogonal polynomials by the Rayleigh-Ritz method. The variation of natural frequencies with the speed of rotation and the mode shapes at different rotational speeds are plotted. The using of orthogonal polynomials for the bending shapes enables the computation of higher natural frequencies of any order to be accomplished without facing any difficulties.

关键词： rotor manipulation mechanism rotor blades Rayleigh-Ritz method

Expression of lignin peroxidase H2.from Phanerochaete chrysosporium by multi-copy recombinant Pichia strain

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Journal of Environmental Sciences 2009年第2期21卷 218-222页

作者： wang Wei,WEN Xianghua Department of Environmental Science and Engineering,tsinghua university,{2.,china. Department of Environmental Science and Engineering Tsinghua University Beijing 100084 China

The lipH2.gene, encoding the expression of lignin peroxidase, was cloned from Phanerochaete chrysosporium BKM-F-1767 and expressed in Pichia pastoris X-33, a yeast. The cDNA of LiPH2.was generated from total RNA extracted from P chrysosporium by PCR with primers that do not contain a P. chrysosporium lignin peroxidase secretion signal. The gene was then successfully inserted into the expression vector pPICZα, and resulted in the recombinant vector pPICZα-lipH2. The transformation was conducted in two ways. One was using the wild Pichia pastoris as the recipients, which results in the recombinant P. pastoris with single or low lipH2.gene copy. The second was using P. pastoris and single or low lipH2.gene copy as the recipients, which results in the recombinant P. pastoris with multi-copies of lipH2.genes. This study firstly expressed the gene lipH2.in P. pastoris and achieved the successful expression of the lipH2.depending upon the generation of a recombinant strain that contained multiple copies. The lignin peroxidase activity reached a maximum of 15 U/L after 12.h induction.

关键词： heterologous expression lignin peroxidase Pichia pastoris

Thermodynamic Significance of Human Basal Metabolism

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Journal of Thermal Science 1993年第2期2卷 81-86页

作者： wang Cuncheng Thermal Engineering Department tsinghua university, {2., P.R. china 1. Thermal Engineering Department tsinghua university 100084 Beijing P.R. China

The human basal state,a non-equilibrium steady state,is analysed in this paper in the light of the First and Second Laws of Thermodynamics whereby the thermodynamic significance of the basal metabolic rate and its distinction to the dissipation function and exergy loss are *** analysis demonstrates the correct expression of the effects of the blood flow on the heat balance in a human-body bio-heat model and the relationship between the basal metabolic rate and the blood perfusion.

关键词： thermodynamic laws basal metabolism blood perfusion dissipation function exergy loss

Reduced analysis and confirmatory research on co-adaptability theoretical solution to conflicting events in construction engineering projects

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Science china(Technological Sciences) 2010年第2期53卷 480-485页

作者： HOU XueLiang1 , LU Mei2.& wang Kai3 1 School of Business Administration, North china Electric Power {2., beijing 102.06, china 2.Department of Construction Management, tsinghua university, beijing 100084, china 3 College of Management, beijing Jiaotong {2., beijing 100084, china 1. School of Business Administration North China Electric Power University Beijing 102206 China2. Department of Construction Management Tsinghua University Beijing 100084 China3. College of Management Beijing Jiaotong University Beijing 100084 China

The co-adaptability theoretical solution to conflicting events in construction engineering projects has three problems. First, the transformation of constraint conditions of theoretical solution is very difficult in practical engineering applications; second, some coefficients are difficult to be determined; third, there are overfull circular arithmetic operations involved in it. To resolve these problems, a new method to reduce the theoretical solution complications is proposed. By analyzing the operating mechanism of theoretical solution model, redundancies in the theoretical solution can be eliminated, and the ISM mapping with the co-adaptability solution can be set up. Based on this approach, a procedure to solve practical conflicting events in construction projects is established by replacing characteristic variables with mathematic variables. The research results show that the procedure can replace the co-adaptability theoretical solution effectively and solve practical conflicting events in construction projects.

关键词： construction project conflict theoretical solution reduced analysis ISM confirmatory research

A formal method to real-time protocol interoperability testing

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Science in china(Series F) 2008年第11期51卷 1723-1744页

作者： wang ZhiLiang1,3,YIN Xia2.3 & JING ChuanMing2.3 1 Network Research Center,tsinghua university,{2.,china 2.Department of Computer Science and Technology,tsinghua university,{2.,china 3 tsinghua National Laboratory for Information Science and Technology(TNList) ,{2.,china 1. Network Research Center Tsinghua University Beijing 100084 China 3. tsinghua National Laboratory for Information Science and Technology (TNList) Beijing 100084 China 2. Department of Computer Science and Technology Tsinghua University Beijing 100084 China

Interoperability testing is an important technique to ensure the quality of implementations of network communication protocol. In the next generation Internet protocol, real-time applications should be supported effectively. However, time constraints were not considered in the related studies of protocol interoperability testing, so existing interoperability testing methods are difficult to be applied in real-time protocol interoperability testing. In this paper, a formal method to real-time protocol interoperability testing is proposed. Firstly, a formal model CMpTIOA （communicating multi-port timed input output automata） is defined to specify the system under test （SUT） in real-time protocol interoperability testing; based on this model, timed interoperability relation is then defined. In order to check this relation, a test generation method is presented to generate a parameterized test behavior tree from SUT model; a mechanism of executability pre-determination is also integrated in the test generation method to alleviate state space explosion problem to some extent. The proposed theory and method are then applied in interoperability testing of IPv6 neighbor discovery protocol to show the feasibility of this method.

关键词： protocol testing interoperability testing real-time testing test generation timed input output automata(TIOA)

Particle modulations to turbulence in two-phase round jets

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Acta Mechanica Sinica 2009年第5期25卷 611-617页

作者： Bing wang Huiqiang Zhang Yi Liu Xiaofen Yan Xilin wang School of Aerospace, {2., 100084 beijing, china School of Aerospace Tsinghua University 100084 Beijing China

The particle modulations to turbulence in round jets were experimentally studied by means of two-phase velocity measurements with Phase Doppler Anemometer （PDA）. Laden with very large particles, no significant attenuations of turbulence intensities were measured in the farfields, due to small two-phase slip velocities and particle Reynolds number. The gas-phase turbulence is enhanced by particles in the near-fields, but it is significantly attenuated by the small particles in the far-fields. The smaller particles have a more profound effect on the attenuation of turbulence intensities. The enhancements or attenuations of turbulence intensities in the far-fields depends on the energy production, transport and dissipation mechanisms between the two phases, which are determined by the particle prop- erties and two-phase velocity slips. The non-dimensional parameter CTI is introduced to represent the change of turbulence intensity.

关键词： Particle modulations Turbulence intensity Particle sizes Two-phase slip velocity Particle-laden round turbulent jet

Research on Electric Impedance Spectroscopy of Living Cell Suspensions by a Chip with Microelectrodes

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稀有金属材料与工程 2006年第S3期 429-432页

作者： Xing Yang~(1,2.3) Zhaoying Zhou~(1,2.3) Mingfei Xiao~(1,2.3) Ying Wu~(1,2.3) Shangfeng Liu~4 (1.MEMS Lab.,Department of precision instruments & Mechanology,{2.,beijing 100084,china) (2.Micro-Nano Technology Research Center,{2.,beijing 100084,china) (3.State Key Laboratory of precision Measurement Technology and instruments,{2.,beijing 100084,china) (4.School of Medicine,{2.,beijing 100084,china)

A microfabricated electrical impedance spectroscopy (EIS) chip with microelectrodes was *** substrate and the electrodes of the chip were made of glass and gold,*** experimental results demonstrated that the EIS-chip could distinguish different solutions (physiological saline,culture medium,living cell suspension etc.) by scanning from 10Hz to 45kHz.A 6-element circuit model was used for fitting the real part and the imaginary part admittance curves of the living cell *** actual circuit was also built and tested to verify the 6-element circuit model *** micro-EIS chip has several advantages including the use of small sample volumes,high resolution and ease of *** shows good application prospects in the areas of cellular electrophysioiogy,drug screening and bio-sensors etc.

关键词： electrical impedance spectroscopy(EIS) microelectrode living cell suspension 6-element

The geometrical structure, electronic structure and magnetism of bimetallic Au_nM_2.(n=1, 2. M=Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd) clusters

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Science china(Physics,Mechanics & Astronomy) 2009年第7期52卷 1011-1020页

作者： GU Juan1,2. wang ShanYing2.& GOU BingCong1 1 Department of Physics, beijing Institute of Technology, beijing 100081, china 2.Department of Physics, tsinghua university, beijing 100084, china Department of Physics Beijing Institute of Technology Beijing 100081 China Department of Physics Tsinghua University Beijing 100084 China

The geometrical structure, stability, magnetism, and electronic structure of bimetallic clusters AuM2.and Au2.2. where M are 4d transition metal elements, are investigated systematically by using the first-principles method based on density functional theory. The calculation results show that there is a large amount of low-energy isomers with the very similar structure. AuM2.and Au2.2.clusters display dramatic magnetism. The magnetic moment of the 4d element is either enhanced or weakened with respect to the bulk value, which is largely dependent on the orbital exchange-splitting.

关键词： density functional theory first-principles cluster electronic structure magnetism