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BLOW-UP SOLUTIONS FOR A CLASS OF NONLINEAR PARABOLIC EQUATIONS WITH MIXED BOUNDARY CONDITIONS

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Journal of Systems Science & Complexity 2005年第2期18卷 265-276页

作者： dingJuntang LIShengjia schoolofmathematicalsciences ShanxiUniversityTaiyuan030006China

By constructing an auxiliary function and using Hopf 's maximum principles onit, existence theorems of blow-up solutions, upper bound of 'blow-up time' and upper estimates of'blow-up rate' are given under suitable assumptions on a, b, f, g, σ and initial date u_0(x). Theobtained results are applied to some examples in which a, b, f, g and σ are power functions orexponential functions.

关键词： nonlinear parabolic equations blow-up solutions blow-up time blow-up rate maximum principles

Threading dislocation density comparison between GaN grown on the patterned and conventional sapphire substrate by high resolution X-ray diffraction

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Science china(Physics,Mechanics & Astronomy) 2010年第3期53卷 465-468页

作者： ZHANG YuChao1, XING ZhiGang2, MA ZiGuang2, CHEN Yao2, ding GuoJian2, XU PeiQiang2, DONG ChenMing3, CHEN Hong2 & LE XiaoYun1 1 school of Physics and Nuclear Energy Engineering, Beihang university, Beijing 100190, china 2 Renewable Energy Laboratory, Institute of Physics, Chinese Academy of sciences, Beijing 100190, china 3 school of Information and Communication, tianjin Polytechnic university, tianjin 300160, china school of Physics and Nuclear Energy Engineering Beihang University Beijing China Renewable Energy Laboratory Institute of Physics Chinese Academy of Sciences Beijing China school of Information and Communication Tianjin Polytechnic University Tianjin China

GaN epifilms are grown on the patterned sapphire substrates (PSS) (0001) and the conventional sapphire substrates (CSS) (0001) by metal-organic chemical vapor deposition (MOCVD) using a novel two-step growth. High resolution X-ray diffraction (HR-XRD) is used to investigate the threading dislocation (TD) density of the GaN epifilms. The TD density is calculated from the ω-scans full width at half maximum (FWHM) results of HR-XRD. The edge dislocation destiny of GaN grown on the PSS is 2.7×108 cm-2, which is less than on the CSS. This is confirmed by the results of atomic force microscopy (AFM) measurement. The lower TD destiny indicates that the crystalline quality of the GaN epifilms grown on the PSS is improved compared to GaN epifilms grown on the CSS. The residual strains of GaN grown on the PSS and CSS are compared by Raman Scattering spectra. It is clearly seen that the residual strain in the GaN grown on PSS is lower than on the CSS.

关键词： GaN patterned sapphire substrate threading dislocation XRD

Rock fracture mechanism of buffer blasting with cushion layer at the borehole bottom

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 325-334页

作者： Xinguang Zhu Chenxi ding Zhe Sui Hong Su Xu Guo school of Civil and Resources Engineering University of Science and Technology BeijingBeijing 100083China Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing 100190China school of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 100083China school of Chemical and Blasting Engineering Anhui University of Science and TechnologyHuainan 232001China

This study primarily investigates the rock fracture mechanism of bottom cushion layer blasting and explores the effects of the bottom cushion layer on rock *** involves analyses of the evolution patterns of blasting stress,characteristics of crack distribution,and rock fracture features in the ***,blasting model experiments were carried out using the dynamic caustics principle to investigate the influence of bottom cushion layers and initiation methods on the integrity of the bottom rock *** experimental results indicate that the combined use of bottom cushion layers and inverse initiation effectively protects the integrity of the bottom rock ***,the process of stress wave propagation and dynamic crack propagation in rocks was simulated using the continuum-discontinuum element method(CDEM)and the Landau explosion source model,with varying thicknesses of bottom cushion *** numerical simulation results indicate that with increasing cushion thickness,the absorption of energy generated by the explosion becomes more pronounced,resulting in fewer cracks in the bottom rock *** illustrates the positive role of the cushion layer in protecting the integrity of the bottom rock mass.

关键词： bottom cushion layer blasting crack propagation continuum-discontinuum element method dynamic stress intensity factor

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预测手段有效性的一个统计检验方法

天津大学学报（自然科学与工程技术版） 2004年第2期37卷 162-166页

作者：刘嘉焜丁春蕾王公恕天津大学理学院天津300072 南开大学数学科学学院天津300071

针对预报方法的"有效性"问题,以地震预报为例建立统计假设H0,即预测手段与地震流无关,通过构造适当的统计量,用统计检验的方法判别预测手段和方法是否有效.该方法判断结果错误的概率不超过预先给定值α=15%,从而为判断多种预报方法的有... 详细信息

针对预报方法的"有效性"问题,以地震预报为例建立统计假设H0,即预测手段与地震流无关,通过构造适当的统计量,用统计检验的方法判别预测手段和方法是否有效.该方法判断结果错误的概率不超过预先给定值α=15%,从而为判断多种预报方法的有效性问题提供了一个检验方法.

关键词：预测手段有效性统计检验方法地震自然灾害

The representation theorem of onto isometric mappings between two unit spheres of l∞-type spaces and the application on isometric extension problem

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Science china Mathematics 2004年第5期47卷 722-729页

作者： ding guanggui school of mathematical sciences and lpmc Nankai University Tianjin 300071 China

In this paper, we first derive the representation theorem of onto isometric mappings in the unit spheres of real l∞-type spaces, then we conclude that such mappings can be extended to the whole space as (real) linear... 详细信息

关键词： isometric mapping, isometric extension.

Identification and Categorization of Horizontally Transferred Genes in Prokaryotic Genomes

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Acta Biochimica et Biophysica Sinica 2005年第8期37卷 561-566页

作者： Shuo-Yong SHI~1 Xiao-Hui CAI~1 and Da-fu ding~(1,2*) Key Laboratory of Proteomics.Institute of Biochemistry and Cell Biology.Shanghai Institutes for Biological sciences,Chinese Academy of sciences,Graduate school of the Chinese Academy of sciences.Shanghai 200031,china ~2 school of Life Science & Technology.Shanghai Jiaotong university.Shanghai 200030.china Key Laboratory of Proteomics Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of SciencesShanghai 200031 China school of Life Science & Technology Shanghai Jiaotong UniversityShanghai 200030 China

Horizontal gene transfer(HGT),a process through which genomes acquire genetic materialsfrom distantly related organisms,is believed to be one of the major forces in prokaryotic genome ***,systematic investigation is still scarce to clarify two basic issues about HGT:(1) what types ofgenes are transferred:and(2)what influence HGT events over the organization and evolution of ***-scale investigations of these two issues will advance the systematical understanding ofHGT in the context of prokaryotic genome *** investigated 82 genomes,we constructed anHGT database across broad evolutionary *** identified four function categories containing a highproportion of horizontally transferred genes:cell envelope,energy metabolism,regulatory functions,andtransport/binding *** biased function distribution indicates that HGT is not completely random;instead,it is under high selective pressure,required by function restraints in ***,wemapped the transferred genes onto the connectivity structure map of organism-specific pathways listed inKyoto Encyclopedia of Genes and Genomes(KEGG).Our results suggest that recruitment of transferredgenes into pathways is also selectively constrained because of the tuned interaction between original *** organization structures still conserve well through evolution even with the recruitment ofhorizontally transferred ***,in pathways whose organization were significantly affected byHGT events,the operon-like arrangement of transferred genes was found to be *** resultssuggest that operon plays an essential and directional role in the integration of alien genes into pathways.

关键词： genome evolution horizontal gene transfer function and pathway analysis

Overview of HBV whole genome data in public repositories and the Chinese HBV reference sequences

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Progress in Natural Science:Materials International 2008年第1期18卷 13-20页

作者： Guanghua Wu a,b, Huiguo ding c, Changqing Zeng b,* a Graduate school of Chinese Academy of sciences, Beijing 100049, china b Beijing Institute of Genomics, Chinese Academy of sciences, Beijing 101300, china c Beijing Youan Hospital, Capital Medical university, Beijing 100069, china Graduate school of Chinese Academy of sciences Beijing 100049 China Beijing Institute of Genomics Chinese Academy of Sciences Beijing 101300 China Beijing Youan Hospital Capital Medical University Beijing 100069 China

The number of Hepatitis B virus (HBV) whole genomic sequences in public nucleotide databases (GenBank, EMBL, and DDBJ) had reached 866 by January 1, 2007. Coming from 46 countries and regions, these sequences were categorized as eight genotypes (A–H). With the statistical and phylogenetic analysis on all available complete genomic data of HBV, we here present an overview of HBV sequences in public databases. From all registered 229 HBV genomes in Chinese regions as well as 59 sequencing data from our research group, we report the establishment of reference sequences of HBV strains prevailing in china. These analyses provide clues for the effects of HBV genotypes in host clinical progressions, geographic distribution of the infection, and the viral evolutionary history. Moreover, the viral sequence reference would be helpful in the identiffcation of various HBV mutations. Based on the analysis of various public databases, we suggest that the Chinese HBV database with the clinical information should be constructed.

关键词： Public databases HBV genomic sequences Genotype Subtype Chinese reference sequences

An elastic-plastic analysis of short-leg shear wall structures during earthquakes

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Earthquake Engineering and Engineering Vibration 2012年第4期11卷 525-540页

作者： ding Jianguo Zhu Ying school of sciences Nanjing University of Science and Technology Huaxin Consulting CO. Ltd

Short-leg shear wall structures are a new form of building structure that combine the merits of both frame and shear wall structures. Its architectural features, structure bearing and engineering cost are reasonable. To analyze the elastic-plastic response of a short-leg shear wall structure during an earthquake, this study modified the multiple-vertical-rod element model of the shear wall, considered the shear lag effect and proposed a multiple-vertical-rod element coupling beam model with a new local stiffness domain. Based on the principle of minimum potential energy and the variational principle, the stiffness matrixes of a short-leg shear wall and a coupling beam are derived in this study. Furthermore, the bending shear correlation for the analysis of different parameters to describe the structure, such as the beam height to span ratio, short-leg shear wall height to thickness ratio, and steel ratio are introduced. The results show that the height to span ratio directly affects the structural integrity; and the short-leg shear wall height to thickness ratio should be limited to a range of approximately 6.0 to 7.0. The design of short-leg shear walls should be in accordance with the ＂strong wall and weak beam＂ principle.

关键词： short-leg shear wall multiple-vertical-rod element model shear lag effect bending shear correlationcoefficient coupling beam stiffness matrix elastic-plastic analysis

Application of Phage-displayed Single Chain Antibodies in Western Blot

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Acta Biochimica et Biophysica Sinica 2005年第3期37卷 205-209页

作者： Yan-Li ding Mei-Yun LIU Wei HAN Sheng-Li YANG Hui LIU Yi GONG school of Pharmaceutical Engineering,Shenyang Pharmaceutical university,Shenyang 110015,china Shanghai Research Center of Biotechnology,Chinese Academy of sciences,Shanghai 200233,china school of Pharmaceutical Engineering Shenyang Pharmaceutical UniversityShenyang 110015 China Shanghai Research Center of Biotechnology Chinese Academy of SciencesShanghai 200233 China

A phage display single chain fragment variable library constructed on pⅢ protein of M13filamentous phage was screened using B-lymphocyte stimulator and FP248 as selective *** fourrounds of panning,there was a remarkable enrichment in the titer of bound *** phage cloneswere selected from the last round and screened by means of *** the antibody phages asprimary antibodies in Western blot,we developed a method for detecting the specific *** dilutions ofantibody phages depend on the affinity between antibody-displayed phage particles and antigens.

关键词： phage-display antibody Western blot