检索结果-南通市图书馆

The kink-soliton and antikink-soliton in quasi-one-dimensional nonlinear monoatomic lattice

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2005年第2期48卷 150-157页

作者： XU Quan1 & TIAN Qiang2.1. Scientific and Technological Office, Daqing Teacher College, Daqing 163712. China 2. department of Physics , beijing Normal University, beijing 100875, China Scientific and Technological Office Daqing Teacher College Daqing 163712 China department of Physics Beijing Normal University Beijing 100875 China

The quasi-one-dimensional nonlinear monoatomic lattice is analyzed. The kink-soliton and antikink-soliton are presented. When the interaction of the lattice is strong in the x-direction and weak in the y-direction, the two-dimensional (2.) lattice changes to a quasi-one-dimensional lattice. Taking nearest-neighbor interaction into account, the vibration equation can be transformed into the KPI, KPII and MKP equation. Considering the cubic nonlinear potential of the vibration in the lattice, the kink-soliton solution is presented. Considering the quartic nonlinear potential and the cubic interaction potential, the kink-soliton and antikink-soliton solutions are presented.

关键词： two-dimensional nonlinear lattice, quasi-one-dimensional nonlinear lattice, kink-soliton, antikink-soliton.

Molecular modeling and spectroscopic studies on the binding of guaiacol to human immunoglobulin

在线全文

学校读者我要写书评

暂无评论

Science China chemistry 2006年第6期49卷 550-559页

作者： HE Wenying1,2. YAO Xiaojun1, LIU Pengjun2. GAO Zhenxia2.& HU Zhide1 1. department of chemistry, Lanzhou University, Lanzhou 730000, China {2., Hainan Normal University, Hainan 571158, China 1. department of chemistry Lanzhou University Lanzhou 730000 China 2. department of chemistry Hainan Normal University Hainan 571158 China

The fluorogenic property of guaiacol was exploited for the first time to analyze the interaction with target protein as a probe by molecular modeling, fluorescence, circular dichroism (CD) and Fourier transform infrared (FT-IR) spectroscopy. Molecular docking was performed to reveal the possible binding mode or mechanism and suggested that guaiacol can strongly bind to human immu- noglobulin (HIgG). It is considered that guaiacol binds to HIgG mainly by a hydrophobic interaction and there are two hydrogen bond interactions between the drug and the residues LEU 80 and ASP 65, which is in good agreement with the results from the experimental thermodynamic parameters (the enthalpy change △H0 and the entropy change △S0 were calculated to be 65.55 kJ·mol-1 and 132.95 J·mol-1·K-1 according to the Vant’ Hoff equation). Data obtained by the fluorescence spectroscopy indicated that binding of guaiacol with HIgG leads to dramatic enhancement in the fluorescence emission intensity along with significant occurrence of efficient Frster resonance energy transfer (FRET) from the residue of HIgG to the protein bound guaiacol. From the low value of fluorescence anisotropy (r = 0.06), it is argued that the probe molecule is located in the motionally unrestricted environment of the protein. The alterations of protein’s secondary structure in the presence of guaiacol in aqueous solution were quantitatively calculated by the evidences from FT-IR and CD spectroscopes.

关键词： guaiacol, human immunoglobulin, molecular modeling, fluorescence enhancement, Fourier transform infrared (FT-IR) spectroscopy, circular dichroism (CD).

Analysis of the observation of particle detector inside ‘CBERS-1’ satellite under solar quiet conditions

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2006年第3期49卷 342-357页

作者： ZOU Hong1, XIAO Zuo1, HAO Yongqiang1, ZOU Jiqing1, ZHU Wenming2. WU Zhongxiang2.& XIANG Hongwen2.1. department of Geophysics, Peking University, beijing 100871, China 2. Chinese Academy of Space Technology, {2. 100086, China department of Geophysics Peking University Beijing 100871 China Chinese Academy of Space Technology Beijing 100086 China

Based on the knowledge and related theory of earth’s radiation belt, the data of energetic particles observed by detectors onboard ‘CBERS-1’ satellite at a solar syn- chronous orbit were analyzed. It is proved that the observational results are in agreement with the theoretical description of the radiation belt structures. Analysis of more than 3 years’ data showed clearly that under quiet solar conditions, at a height of about 800 km the energetic particles were mainly located in three regions: northern auroral belt (40°― 80°), southern auroral belt (?40°― ?80°) and South Atlantic Geomagnetic Anomaly Re- gion (SAA). Actually, this is for the global distribution, at each longitude the latitudinal coverage is much narrower and particles are along the geomagnetic latitude of about ±60°. The species of particles in different regions and their counting rates are different. In SAA, usually both electrons and protons are observed, which should come from inner radiation belt; in polar regions only energetic electrons are observed under the quiet condition, which belongs to the outer radiation belt. The distribution of outer radiation electrons is asymmetrical for longitudes as well as northern and southern polar regions. These asymmetries can be explained with the reflecting altitudes of the mirror points of charged particles at the same L shell.

关键词： radiation-belts, energetic-particle, drift-shell, mirror-point.

Comparative study of the effect of Cu_2. and MoO_3 on flame retardance and smoke emission of PVC by Cone and TGA

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1998年第13期43卷 1090-1094页

作者： LI Bin\+1 and WANG Jianqi\+2.1. department of chemistry, Northeast Forestry University, Harbin 150040, China 2. National Laboratory of Flame Retardant Materials, {2. Institute of Technology, {2., 100081, China department of chemistry Northeast Forestry University Harbin China National Laboratory of Flame Retardant Materials Beijing Institute of Technology Beijing China

Cuprous and molybdic oxides exhibit extremely effectiveness in smoke suppression for PVC. However, few are the data reported concerning flame retardance and smoke emission of PVC taken from Cone calorimetry relative to the conventional thermal analysis technique. Abundant data from Cone calorimetry have been acquired. Data analysis was achieved through the study of MLR, HRR, SEA tested at irradiance of 2. kWm -2.. The understandable flame retardance of PVC/Cu\-2. and PVC/MoO\-3 relative to pure PVC has been rationalized by their lowered heat release rates and enhanced char residues. The difference in smoke reduction between these two oxides consists in the time scale. As clearly seen under air atmosphere both oxides exert themselves to the afterglow which has been recognized as a dangerous source, in particular in the full_scale fire situation.

关键词： cone calorimetry poly(vinyl chloride) flame retardation smoke emission cuprous oxide molybdic oxide.

Empirical likelihood confidence regions of the parameters in a partially linear single-index model

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2005年第10期48卷 1333-1348页

作者： XUE Liugen~1 & ZHU Lixing~2.1. College of Applied Sciences,beijing University of Technology,beijing 10002.,China 2. {2. of Mathematics,Hong Kong Baptist University,Hong Kong,China 1. College of Applied Sciences Beijing University of Technology 100022 Beijing China 2. department of Mathematics Hong Kong Baptist University Hong Kong China

In this paper, a partially linear single-index model is investigated, and three empirical log-likelihood ratio statistics for the unknown parameters in the model are suggested. It is proved that the proposed statistics are asymptotically standard chi-square under some suitable conditions, and hence can be used to construct the confidence regions of the parameters. Our methods can also deal with the confidence region construction for the index in the pure single-index model. A simulation study indicates that, in terms of coverage probabilities and average areas of the confidence regions, the proposed methods perform better than the least-squares method.

关键词： partially linear single-index model, empirical likelihood, confidence region, chi-square distribution, coverage probability.

Mathematic Expression of Kinetic Compensation Effect and Relationship between the Exothermic Decomposition Temperature and Critical Temperature of Thermal Explosion of Eighty-six Energetic Materials

在线全文

学校读者我要写书评

暂无评论

含能材料 2001年第1期9卷 8-9页

作者： HU Rong zu 1, YANG De suo 2. ZHANG Jiao qiang 3 (1. department of chemistry,Northwest University, Xi′an 710065, China {2. and Chemical Engineering, Baoji College of Arts and Science, Baoji 72.007, China 3. department of 西北大学陕西西安 710065 宝鸡文理学院陕西 721007 西北工业大学陕西西安 710072

Two relationships are established using the least squares method,between the kinetic parameters (the apparent activation energy and pre exponential constant),and the exothermic decomposition temperature and ther... 详细信息

关键词： critical temperature of thermal explosion decomposition temperature DSC energetic materials.

The refined theory of deep rectangular beams based on general solutions of elasticity

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2006年第3期49卷 291-303页

作者： GAO Yang1 & WANG Minzhong2.1. College of Science, China Agricultural University, beijing 100083, China 2. State Key Laboratory for Turbulence and Complex Systems and department of Mechanics and Engi- neering Science, Peking University,{2., China College of Science China Agricultural University Beijing 100083 China State Key Laboratory for Turbulence Complex Systems department of Mechanics Engineering Science Peking University Beijing 100871 China

The problem of deducing one-dimensional theory from two-dimensional the- ory for a homogeneous isotropic beam is investigated. Based on elasticity theory, the re- fined theory of rectangular beams is derived by using Papkovich-Neuber solution and Lur’e method without ad hoc assumptions. It is shown that the displacements and stresses of the beam can be represented by the angle of rotation and the deflection of the neutral surface. Based on the refined beam theory, the exact equations for the beam without transverse surface loadings are derived and consist of two governing differential equations: the fourth-order equation and the transcendental equation. The approximate equations for the beam under transverse loadings are derived directly from the refined beam theory and are almost the same as the governing equations of Timoshenko beam theory. In two ex- amples, it is shown that the new theory provides better results than Levinson’s beam the- ory when compared with those obtained from the linear theory of elasticity.

关键词： deep rectangular beams,the refined theory,Papkovich-Neuber solution,Lur'e method,governing equation

The refined theory of transversely isotropic piezoelectric rectangular beams

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2006年第4期49卷 473-486页

作者： GAO Yang1 & WANG Minzhong2.1. College of Science, China Agricultural University, beijing 100083, China 2. State Key Laboratory for Turbulence and Complex Systems and department of Mechanics and Engi- neering Science, Peking University,{2., China 1. College of Science China Agricultural University Beijing 100083 China 2. State Key Laboratory for Turbulence and Complex Systems and department of Mechanics and Engineering Science Peking University Beijing 100871 China

The problem of deducing one-dimensional theory from two-dimensional theory for a transversely isotropic piezoelectric rectangular beam is investigated. Based on the piezoelasticity theory, the refined theory of piezoelectric beams is derived by using the general solution of transversely isotropic piezoelasticity and Lur'e method without ad hoc assumptions. Based on the refined theory of piezoelectric beams, the exact equations for the beams without transverse surface loadings are derived, which consist of two governing differential equations: the fourth-order equation and the transcendental equation. The approximate equations for the beams under transverse loadings are derived directly from the refined beam theory. As a special case, the governing differential equations for transversely isotropic elastic beams are obtained from the corresponding equations of piezoelectric beams. To illustrate the application of the beam theory developed, a uniformly loaded and simply supported piezoelectric beam is examined.

关键词： rectangular beams, the refined theory, piezoelectric, transversely isotropic.

On three-dimensional geological modeling and visualization

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2004年第8期47卷 739-748页

作者： WU Qiang1 & XU Hua2.1. department of Resource Exploitation Engineering, China University of Mining and Technology, beijing 100083, China 2. beijing Institute of Petrochemical Technology, beijing 102.17, China 1. department of Resource Exploitation Engineering China University of Mining and Technology 100083 Beijing China 2. beijing Institute of Petrochemical Technology 102617 Beijing China

The technology of 3D geological modeling will bring about great changes in the methods of geological data acquiring, storing, processing and displaying. However, no perfect or convenient software systems have been developed up to now since the geologic data which re-flect geological entities bear the feature of diversity, uncertainty and complexity. Some supervoxel models, mathematical models of fault and geometrical models of fold have been contrived so as to show the space geometric configuration of the complicated geologic structures. The application-oriented system architecture for 3D geological modeling is established; and a novel design concept based on spatial data processing is also proposed with the technology of solid modeling as its core and the application of models as its objective. Theories and methods for 3D geological modeling will hopefully be enriched and developed. In the light of these theories and methods, a feature-based navigation visualization technique is also put forward in the paper. By integrating geo-database, graphics libraries and KBS with 3D dynamic simulation systems, geologists will be able to capture the partial characteristics and whole structure embodied in the geological data in a direct-viewing, figurative and accurate manner.

关键词： 3D geological modeling,geometrical model,system architecture,visualization