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Science China(Technological Sciences) 2007年第5期50卷 664-673页

作者： LI ZhiLin LI ZhiFeng huang Qin College of Materials Science and Engineering Beijing University of Chemical Technology Beijing 100029 China College of Materials Science and Engineering Beijing University of Chemical Technology Beijing 100029 China College of Materials Science and Engineering Beijing University of Chemical Technology Beijing 100029 China

Diamond and cubic boron nitride films have already been applied practically be- cause of their excellent properties. The specific orientations of the films have spe- cial meaning on their application in optics and microelectronics fields. In this paper, the relative electron density differences of the interface between the different crystal planes of silicon substrate and those of diamond and cubic boron films are calculated with the empirical electron theory in solids and molecules. Analyses on the calculation results show that in the range of the researched films, the smaller the relative electron density difference between the film and the substrate is, the stabler the film is in thermodynamics. Therefore, the electron density difference is the essential factor of determining the orientation of the texture and heteroepitaxy of the films. The deductions accord well with the experimental facts. The calcula- tion methods and the theory not only provide a new angle of view for the research of the growth mechanism of diamond film and cubic boron nitride film on the sili- con substrate, but also provide a possible direction for the prediction of the orien- tation of other films.

关键词： films, interface electron density, texture, heteroepitaxy, diamond, cubic boron nitride

Commuting Solutions of a Quadratic Matrix Equation for Nilpotent Matrices

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Algebra Colloquium 2018年第1期25卷 31-44页

作者： Qixiang Dong Jiu Ding Qianglian huang School of Mathematical Sciences Yangzhou University Yangzhou Jiangsu 225002 China Department of Mathematics University of Southern Mississippi Hattiesburg MS 39406 USA

We solve the quadratic matrix equation AXA = XAX with a given nilpotent matrix A, to find all commuting solutions. We first provide a key lemma, and consider the special case that A has only one Jordan block to motivate the idea for the general case. Our main result gives the structure of all the commuting solutions of the equation with an arbitrary nilpotent matrix.

关键词： quadratic matrix equation nilpotent matrix Jordan canonical form Toeplitz matrix commuting solution

Coordinative Development Between Land Use Change and Regional Population-Resources-Environment-Development System—A Case Study of Jiangsu Province

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Chinese Geographical Science 2007年第4期17卷 289-296页

作者： XIAO Sisi huang Xianjin PENG Buzhuo School of Geographic ＆ Oceanographic Sciences Nanjing University Nanjing 210093 China

Land use change has significant influence on the operation of the PopulationResources-Environment-De-velopment (PRED) System. Moderate land use is the key factor to ensure the coordinative and sustainable development between land use and PRED system. Based on the internal relationship between land use and PRED system, a PRED evaluation index system and a Press-Status-Response (PSR) model were established in this study. According to the expounding on the mechanism of the PSR model, we investigated the coordinative development between the changes of regional land use and PRED system taking Jiangsu Province as an example. The results showed that the orders of the Synthetic Index of Land Use (SILU) and the Variation of PRED Index (VPI) in Jiangsu are both the southern Jiangsu>the central Jiangsu>the northern Jiangsu. A cubic curve model was used to fit the relationship between the VPI and SILU. The inflection point of VPI was situated in 5.0 of SILU. When SILU was below 5.0, VPI increased with SILU, which will be helpful to the coordinative development between land use and PRED system. Based on those results, it is suggested that the land use degree of the southern Jiangsu, especially that of Nanjing City, should be moderately controlled at present, while land resources of the central Jiangsu and the northern Jiangsu should be further exploited.

关键词： land use change Population-Resources-Environment-Development (PRED) system Press-Status-Response (PSR) model coordinative development Jiangsu Province China

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基于时频平面脊信息提取的电能质量扰动检测

高电压技术 2008年第4期34卷 772-776页

作者：李玲金国彬黄绍平湖南工程学院湘潭411104

针对目前电能质量扰动检测方法的局限性,提出了一种基于时频平面脊信息提取的电能质量扰动检测识别新方法。该方法首先基于自适应最优核时频分布理论得到电能质量扰动信号的时频分布,然后提取了时频平面脊信息和基频脊幅值;结合时频平... 详细信息

针对目前电能质量扰动检测方法的局限性,提出了一种基于时频平面脊信息提取的电能质量扰动检测识别新方法。该方法首先基于自适应最优核时频分布理论得到电能质量扰动信号的时频分布,然后提取了时频平面脊信息和基频脊幅值;结合时频平面的脊信息和基频幅值有效实现了对各种电能质量扰动的检测与识别。仿真测试结果表明:该方法表现出很高的时频聚集性,且不受交叉项的影响,清晰地刻画出各种扰动的时频分布特征,快速、准确地实现了各种电能质量扰动的检测与识别。

关键词：时频分布平面脊电能质量扰动检测方法

Mechanics and thermal management of stretchable inorganic electronics

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National Science Review 2016年第1期3卷 128-143页

作者： Jizhou Song Xue Feng Yonggang huang Department of Engineering Mechanics and Soft Matter Research Center Zhejiang University Key Laboratory of Applied Mechanics Department of Engineering MechanicsTsinghua University Center for Mechanics and Materials Tsinghua University Department of Civil and Environmental Engineering Department of Mechanical EngineeringCenter for Engineering and Healthand Skin Disease Research CenterNorthwestern University

Stretchable electronics enables lots of novel applications ranging from wearable electronics, curvilinear electronics to bio-integrated therapeutic devices that are not possible through conventional electronics that is rigid and flat in nature. One effective strategy to realize stretchable electronics exploits the design of inorganic semiconductor material in a stretchable format on an elastomeric substrate. In this review, we summarize the advances in mechanics and thermal management of stretchable electronics based on inorganic semiconductor materials. The mechanics and thermal models are very helpful in understanding the underlying physics associated with these systems, and they also provide design guidelines for the development of stretchable inorganic electronics.

关键词： stretchable electronics buckling inorganic semiconductor material thin film

EFFECT OF SURFACE ENERGY ON DISLOCATION-INDUCED FIELD IN HALF-SPACE WITH APPLICATION TO THIN FILM-SUBSTRATE SYSTEMS

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Acta Mechanica Solida Sinica 2009年第5期22卷 436-442页

作者： Ganyun huang Bob Svendsen Zhixing Lu Institute of Mechanics Dortmund University of Technology 44221 Dortmund Germany Sehool of Mechanical Engineering Tianjin University Tianjin 300072 China Department of Mechanical Engineering University of Colorado at Boulder Colorado USA

In this work the elastic field of an edge dislocation in a half-space with the effect of surface energy has been obtained. The elastic field is then used to study the image force on the dislocation, the critical thickness for dislocation generation in epitaxial thin films with strain mismatch and the yielding strength of thin films on substrates. The results show that the image forces on the dislocation deviate from the conventional solutions when the distance of the dislocation from the free surface is smaller than several times of the characteristic length. Also due to the effect of surface energy, the critical thickness for dislocation generation is smaller than that predicted by the conventional elastic solutions and the extent of the deviation depends on the magnitude of mismatch strain. In contrast, the effect of surface energy on the yielding strength for many practical thin films can be neglected except for some soft ones where the characteristic length is comparable to the thickness.

关键词： thin film surface energy effect dislocation half-space critical thickness yielding strength

Hepatitis C virus vaccine development: old challenges and new opportunities

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National Science Review 2015年第3期2卷 285-295页

作者： Dapeng Li Zhong huang Jin Zhong Key Laboratory of Molecular Virology and Immunology Institut Pasteur of Shanghai Shanghai Institutes for Biological SciencesChinese Academy of Sciences Institute Pasteur of Shanghai Chinese Academy of Sciences

Hepatitis C virus(HCV), an enveloped positive-sense single-stranded RNA virus, can cause chronic and end-stage liver diseases. Approximately 185 million people worldwide are infected with HCV. Tremendous progress has been achieved in the therapeutics of chronic hepatitis C thanks to the development of direct-acting antiviral agents(DAAs), but the worldwide use of these highly efective DAAs is limited due to their high treatment cost. In addition, drug-resistance mutations remain a potential problem as DAAs are becoming a standard therapy for chronic hepatitis C. Unfortunately, no vaccine is available for preventing new HCV infection. herefore, HCV still imposes a big threat to human public health, and the worldwide eradication of HCV is critically dependent on an efective HCV vaccine. In this review, we summarize recent progresses on HCV vaccine development and present our views on the rationale and strategy to develop an efective HCV vaccine.

关键词： hepatitis C virus vaccine prophylactic vaccine therapeutic vaccine neutralizing antibody

A dynamic logistic regression for network link prediction

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Science China Mathematics 2017年第1期60卷 165-176页

作者： ZHOU Jing huang DanYang WANG HanSheng Department of Statistics Renmin University of China Department of Statistics Peking University

In social network analysis, link prediction is a problem of fundamental importance. How to conduct a comprehensive and principled link prediction, by taking various network structure information into consideration,is of great interest. To this end, we propose here a dynamic logistic regression method. Specifically, we assume that one has observed a time series of network structure. Then the proposed model dynamically predicts future links by studying the network structure in the past. To estimate the model, we find that the standard maximum likelihood estimation(MLE) is computationally forbidden. To solve the problem, we introduce a novel conditional maximum likelihood estimation(CMLE) method, which is computationally feasible for large-scale networks. We demonstrate the performance of the proposed method by extensive numerical studies.

关键词： conditional likelihood dynamic logistic regression link prediction social networks

Progress in long wavelength emission in fluorene-based electroluminescent blue materials

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Science China Chemistry 2008年第6期51卷 497-520页

作者： JIANG HongJi WAN JunHua huang Wei Jiangsu Key Laboratory for Organic Electronics&Information Displays and Institute of Advanced Materials Nanjing University of Posts&TelecommunicationsNanjing 210046China Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education Hangzhou Normal UniversityHangzhou 310012China

On account of the advantages of organic electroluminescent materials compared with their inorganic counterparts,the development of organic electroluminescent materials is one of the hot areas of the optoelectronic *** and its derivatives,which have an aromatic biphenyl structure with a wide energy gap in the backbones and high luminescent efficiency,have drawn much attention of ma-terial chemists and device ***,one drawback of fluorene-based electroluminescent blue materials is that there is an occurrence of long wavelength emission after annealing the films in air or after operating organic light-emitting diodes for a long *** clarify the origin of this long wave-length emission,the scientists at home and abroad have put forward all kinds of correlative *** the scientists,some thought it was caused by excimer-related species,while some others claimed that it was caused by the fluorenone of photooxdized *** corresponding solutions to this problem have also been proposed and the problem has been partially resolved in some *** present review summarizes and analyzes the progress made on the origin of long wavelength emission in fluorene-based electroluminescent blue materials at home and abroad in the past few *** issues to be addressed and hotspots to be further investigated are also presented and discussed.

关键词： fluorene electroluminescent long wavelength emission fluorenone excimer synthesis

Isolation and identification of symbiotic bacteria from the skin, mouth, and rectum of wild and captive tree shrews

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Zoological Research 2014年第6期35卷 492-499页

作者： Gui LI Ren LAI gang DUAN Long-Bao LYU Zhi-Ye ZHANG huang LIU Xun XIANG Kunming Primate Research Center of the Chinese Academy of Sciences Kunming Institute of Zoology 650223 China Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences & Chinese Academy of Sciences Kunming Yunnan 650223 China Yunnan Agricultural University Kunming Yunnan 650201 China Chinese Academy of Sciences Kunming Yunnan Yunnan Province Kunming Institute of Zoology

Endosymbionts influence many aspects of their hosts’ health conditions, including physiology, development, immunity, metabolism, etc. Tree shrews(Tupaia belangeri chinensis) have attracted increasing attention in modeling human diseases and therapeutic responses due to their close relationship with primates. To clarify the situation of symbiotic bacteria from their body surface, oral cavity, and anus, 12 wild and 12 the third generation of captive tree shrews were examined. Based on morphological and cultural characteristics, physiological and biochemical tests, as well as the 16 S rDNA full sequence analysis, 12 bacteria strains were isolated and identified from the wild tree shrews: body surface: Bacillus subtilis(detection rate 42%), Pseudomonas aeruginosa(25%), Staphlococcus aureus(33%), S. Epidermidis(75%), Micrococcus luteus(25%), Kurthia gibsonii(17%); oral cavity: Neisseria mucosa(58%), Streptococcus pneumonia(17%); anus: Enterococcus faecalis(17%), Lactococus lactis(33%), Escherichia coli(92%), Salmonella typhosa(17%); whereas, four were indentified from the third generation captive tree shrews: body surface: S. epidermidis(75%); oral cavity: ***(67%); anus: L. lactis(33%), E. coli(100%). These results indicate that S. epidermidis, N. mucosa, L. lactis and E. coli were major bacteria in tree shrews, whereas, S. aureus, M. luteus, K. gibsonii, E. faecalis and S. typhosa were species-specific flora. This study facilitates the future use of tree shrews as a standard experimental animal and improves our understanding of the relationship between endosymbionts and their hosts.

关键词： Tree shrew Microbial Separation Identification