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A New Approach to Nonlinear Partial Differential Equations

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Communications in Nonlinear Science and Numerical Simulation 1997年第4期2卷 230-235页

作者： Jihuan HE (shanghai University,shanghai institute of Applied Mathematics and Mechanics,shanghai 2 0 0 0 72 ,china) shanghai University Shanghai Institute of Applied Mathematics and Mechanics Shanghai 200072 China

In this paper,a novel method called variational iteration method is proposed to solve nonlinear partial differential equations without linearization or small *** this method,a correction functional is constructed by a general Lagrange multiplier,which can be identified via variational *** analytical solution can be obtained from its trial- function with possible unknown constants,which can be identified by imposing the boundary conditions,by successively iteration.

关键词： Nonlinear Problems Partial Differential Equations Variational Iteration Method Variational Theory

Some New Approaches to Duffing Equation with Strongly and High Order Nonlinearity (II) Parametrized Perturbation Technique

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Communications in Nonlinear Science and Numerical Simulation 1999年第1期4卷 78-83页

作者： Jihuan HE (shanghai institute of Applied Mathematics and Mechanics, shanghai University, shanghai 200072, china) Email: glliu@*** shanghai institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China

For the strongly nonlinear equations without small parameter, a transformation u = v can be introduced for the nonlinear equation L(u) + N(u) = 0, where L and N are general linear and nonlinear differential operators respectively, P is sufficiently small. Therefore, a strongly non-linear system is transformed into a small parameter system with respect to the new introduced parameter P, thus various traditional perturbation techniques can be applied. By Lindstedt-Poincare method, a perturbation solution for Duffing equation with sib order nonlinearity is obtained, which is valid not only for the small parameter E in the equation, but also for very large values of E.

关键词： perturbation technique nonlinear equation

THE OCCUPATION DENSITY FIELD FOR THE CATALYTIC SUPER-BROWNIAN MOTION

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Chinese Annals of Mathematics,Series B 1999年第4期20卷 447-454页

作者： HONG WENMING(institute of Mathematics, Fudan University shanghai 200433, china) Fudan Univ Inst Math Shanghai 200433 Peoples R China

It is proved that the occupation time of the catalytic super-Brownian motion is absolutely continuous for d = 1, and the occupation density field is jointly continuous and jointly Holder continuous.

关键词： Branching rate functional Brownian collision local time Catalytic super-Brownian motion Occupation time Occupation density field

The relation between black hole masses and Lorentz factors of the jet components in blazars

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Research in Astronomy and Astrophysics 2009年第3期9卷 293-301页

作者： Ming Zhou1,2,3 and Xin-Wu Cao1,2 1 shanghai Astronomical Observatory, Chinese Academy of Sciences, shanghai 200030, china 2 Joint institute for Galaxy and Cosmology (JOINGC) of SHAO and USMC, shanghai 200030, china 3 Graduate School of the Chinese Academy of Sciences, Beijing 100049, china shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Joint institute for Galaxy and Cosmology (JOINGC) of SHAO and USMC Shanghai 200030 China Graduate School of the Chinese Academy of Sciences Beijing 100049 China

We explore the relationship between black hole mass (MBH) and the motion of the jet components for a sample of blazars. The Very Long Baseline Array (VLBA) 2 cm Survey and its continuation: Monitoring of Jets in active galactic nuclei (AGNs) with VLBA Experiments (MOJAVE) have observed 278 radio-loud AGNs, of which 146 blazars have reliable measurements of their apparent velocities of the jet components. We calculate the minimal Lorentz factors for these sources from their measured apparent velocities, and their black hole masses are estimated with their broad-line widths. A sig- nificant intrinsic correlation is found between black hole masses and the minimal Lorentz factors of the jet components. The Eddington ratio is only weakly correlated with the min- imal Lorentz factor, which may imply that the Blandford-Znajek (BZ) mechanism may dominate over the Blandford-Payne (BP) mechanism for the jet acceleration (at least) in blazars.

关键词： black hole physics — galaxies: active — galaxies: jets — galaxies: nuclei

RESEARCH ON MEASURING METHOD OF THE THERMALCONDUCTIVITY FOR HIGHLY POROUS MATERIALS

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Acta Metallurgica Sinica(English Letters) 1997年第3期10卷 213-218页

作者： J Y Wu Z.M. Tang W Shi andR.Z. Wang (institute of Refrigeration and Cryogenics Engineering, shanghai Jiao Tong University, shanghai 200030,china) shanghai Jiaotong Univ Shanghai China

A transient method with rectangular pulse heating has been developed to measure the thermal conductivity of highly porous materials such as activated carbon, zeolite and silica gel. By this method the thermal conductivity can be measured quickly and accu-rately. In this paper, a set of automatically controlled testing equiptnent is *** measuring method is analysed. The thermal conductivities of some samples, such as activated carbon and zeolite, are measured by the equipment. A group of useful data has been obtained.

关键词： thermal conductivity porous material thermophysical property

Understanding SARS with Wolfram Approach

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Acta Biochimica et Biophysica Sinica 2004年第1期36卷 1-10页

作者： Da-Wei LI, Yu-Xi PAN, Yun DUAN, Zhen-De HUNG, Ming-Qing XU, and Lin HE ( Bio-X Life Science Research Center, shanghai Jiao Tong University, shanghai 200030, china institute for Nutritional science, the Chinese Academy of Sciences, shanghai 200031, china ) Bio-X Life Science Research Center Shanghai Jiao Tong University Shanghai 200030 China.

Stepping acquired immunodeficiency syndrome (AIDS), severe acute respiratory syndrome (SARS) as another type of disease has been threatening mankind since late last year. Many scientists worldwide are making great efforts to study the etiology of this disease with different approaches. 13 species of SARS virus have been sequenced. However, most people still largely rely on the traditional methods with some disadvantages. In this work, we used Wolfram approach to study the relationship among SARS viruses and between SARS viruses and other types of viruses, the effect of variations on the whole genome and the advantages in the analysis of SARS based on this novel approach. As a result, the similarities between SARS viruses and other coronavirusxes are not really higher than those between SARS viruses and non-coronaviruses.

关键词： genome sequence SARS visualization Wolfram approach

Formation and Oxidation Resistance of Silicide Coatings for Mo and Mo-Based Alloys

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Journal of Materials Science & Technology 2001年第4期17卷 479-481页

作者： Yu WANG , Yunpeng LI and Xingfang HU shanghai institute of Ceramics, Chinese Academy of Sciences, shanghai 200050, china Chinese Acad Sci Shanghai Inst Ceram Shanghai 200050 Peoples R China

The forming process of silicide coatings on pure Mo and Mo-base alloys, obtained by the gas- phase deposition method. has been studied by examining the microstructure of coatings and the relationship between coating thickness and process parameters. It was shown that the growth of coatings was diffusion-controlled, the diffusion of silicon to be coated into Mo or Mo-base alloys was mainly responsible for the formation of silicide. The relationship between initial silicide thickness and oxidation resistance was also investigated, and the equation of service life of the coatings at high temperature in air is presented.

关键词： Mo Formation and Oxidation Resistance of Silicide Coatings for Mo and Mo-Based Alloys

ON THE COHOMOLOGY OF GENERALIZED RESTRICTED LIE ALGEBRAS

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Chinese Annals of Mathematics,Series B 1998年第4期19卷 421-432页

作者： SHU BIN (institute of Applied Mathematics & Physics, shanghai Maritime University, shanghai 200135, china.) shanghai Maritime Univ Inst Appl Math & Phys Shanghai 200135 Peoples R China

In [21], generalized restricted Lie algebras, defined over a field F of positive characteristic p, were introduced. In this note their cohomology, especially the so-called generalized restricted cohomology is studies. Some reduction properties are obtained. For graded Cartan type Lie algebras the author determines the first Lie-cohomology groups and the first generalized restricted cohomology groups with the coefficients in the highest weight modules from which all irreducible generalized restricted modules are derived.

关键词： Generalized restricted Lie algebras Generalized restricted Cohomology Lie algebras of Cartan type

Conus Peptides-A Rich Pharmaceutical Treasure

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Acta Biochimica et Biophysica Sinica 2004年第11期36卷 713-723页

作者： Cheng-Zhong WANG and Cheng-Wu CHIinstitute of Biochemistry and Cell Biology, shanghai institute of Biological Sciences, the Chinese Academy of Sciences, shanghai 200031, china institute of Neuroscience, the Chinese Academy of Sciences, shanghai 200031, china institute of Protein Research, Tongji University, shanghai 200092, china institute of Biochemistry and Cell Biology Shanghai Institute of Biological Sciences the Chinese Academy of Sciences institute of Neuroscience the Chinese Academy of Science institute of Protein Research Tongji University

Marine predatory cone snails (genus Conus) with over 500 species represent what is arguably the largest single genus of marine animals alive today. All Conus are venomous and utilize a complex mixture of Conus peptide... 详细信息

关键词： Conus peptide conotoxin neuropathic disorder pharmaceutical potency