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Science China Mathematics 2006年第12期49卷 1855-1863页

作者： tan Liang LMAM Department of MathematicsPeking UniversityBeijing 100871China

We study the set of the mapping degrees between simply connected closed manifolds in this paper.

关键词： mapping degree simply connected manifolds Moore space Eilenberg-Maclane space.

Development of Oryza rufipogon and O. sativa Introgression Lines and Assessment for Yield-related Quantitative Trait Loci

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Journal of Integrative Plant Biology 2007年第6期49卷 871-884页

作者： Lubin tan Department of Plant Genetics and Breeding and State Key Laboratory of Agro-biotechnology China Agricultural University Beijing 100094 China Key Laboratory of Crop Heterosis and Utilization of Ministry of Education Beijing 100094 China Key Laboratory of Crop Genetic Improvement and Genome of Ministry of Agriculture China Agricultural University Beijing 100094 China Beijing Key Laboratory of Crop Genetic Improvement China Agricultural University Beijing 100094 China

Introgression lines population was effectively used in mapping quantitative trait loci （QTLs）, identifying favorable genes, discovering hidden genetic variation, evaluating the action or interaction of QTLs in multiple conditions and providing the favorable experimental materials for plant breeding and genetic research. In this study, an advanced backcross and consecutive selfing strategy was used to develop introgression lines （ILs）, which derived from an accession of Oryza rufipogon Griff. collected from Yuanjiang County, Yunnan Province of China, as the donor, and an elite indica cultivar Teqing （O. sativa L.）, as the recipient. Introgression segments from O. rufipogon were screened using 179 polymorphic simple sequence repeats （SSR） markers in the genome of each IL. Introgressed segments carried by the introgression lines population contained 120 ILs covering the whole O. rufipogon genome. The mean number of homozygous O. rufipogon segments per introgression line was about 3.88. The average length of introgressed segments was approximate 25.5 cM, and about 20.8% of these segments had sizes less than 10 cM. The genome of each IL harbored the chromosomal fragments of O. rufipogon ranging from 0.54% to 23.7%, with an overall average of 5.79%. At each locus, the ratio of substitution of O. rufipogon alleles had a range of 1.67-9.33, with an average of 5.50. A wide range of alterations in morphological and yield-related traits were also found in the introgression lines population. Using single-point analysis, a total of 37 putative QTLs for yield and yield components were detected at two sites with 7%-20% explaining the phenotypic variance. Nineteen QTLs （51.4%） were detected at both sites, and the alleles from O. rufipogon at fifteen loci （40.5%） improved the yield and yield components in the Teqing background. These O. rufipogon-O, sativa introgression lines will serve as genetic materials for identifying and using favorable genes from common wild rice.

关键词： common wild rice cultivated rice introgression lines quantitative trait locus yield-related trait.

Eventual Positivity of Hermitian Polynomials and Integral Operators

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Chinese Annals of Mathematics,Series B 2016年第1期37卷 83-94页

作者： Colin tan Department of Mathematics National University of Singapore Block S17 10 Lower Kent Ridge Road Singapore 119076.

Quillen proved that if a Hermitian bihomogeneous polynomial is strictly positive on the unit sphere, then repeated multiplication of the standard sesquilinear form to this polynomial eventually results in a sum of Hermitian squares. Catlin-D'Angelo and Varolin deduced this positivstellensatz of Quillen from the eventual positive-definiteness of an associated integral operator. Their arguments involve asymptotic expansions of the Bergman kernel. The goal of this article is to give an elementary proof of the positive-definiteness of this integral operator.

关键词： Asymptotics Polynomial Positivity

Crystal Structure and Photochromism in Paint of 1,3,3-Trimethyl-6'-dihydro-indolinyl- spiro[2,3'-[3H]-naphtho[2,1-b][1,4]]oxazine

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Chinese Journal of Structural Chemistry 2007年第5期26卷 572-574页

作者： tan Ting-Feng Department of Materials Science ＆ Engineering Tianjin Institute of Urban Construction Tianjin 300384 China

The title compound 2 （C30H27N3O, Mr = 445.55） has been synthesized and its structure was determined by X-ray crystallography method. The crystal is of monoclinic, space group P21/c with a = 17.520（15）, b = 8.640（7）, c = 15.439（13） A, β = 98.642（14）°, V = 2310（3） 3, Dc = 1.281 g/cm^3, μ = 0.780 mm^-1, F（000） = 944, Z = 4, the final R = 0.0671 and wR = 0.1790 for 1952 observed reflections with Ⅰ 〉 2σ（Ⅰ）. X-ray analysis revealed that the interatomic distance of C（20）O（1） is 1.464（4） , longer than that of the normal C-O bond （1.41～1.43 A） in the six-membered heterocycle, but this kind of change coincides with other spiro compounds. The six-membered heterocycle containing spiro Csp3-O is nonplanar. The UV-vis spectra of the title compound in polymer films showed that it exhibits excellent photochromic property.

关键词： spirooxazine crystal structure photochromism

Theory of an m×n apple surface network with special boundary

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Communications in Theoretical Physics 2023年第6期75卷 138-149页

作者： Zhi-Zhong tan Department of physics Nantong UniversityNantong226019China

As is well known,any condition change in a network model will affect the research method and *** paper studies an arbitrary m×n apple surface network with a pair of non-uniform boundary resistors,which is a complex network that has not been solved *** research process of this paper consists of four strict basic steps according to RT-V *** the breakthrough of matrix transformation and eigenvector solution,two exact potential function formulae and two equivalent resistance formulae are derived.A series of applications and special cases are given to help readers understand the *** particular,we have drawn eight visualized potential function images,which can intuitively understand the changing characteristics of potential *** establishment of theoretical results provides a new theoretical basis for related interdisciplinary research.

关键词： surface structure resistor network RT-V method matrix equation potential function exact solution

Preparation of long alumina fibers by sol-gel method using tartaric acid

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International Journal of Minerals,Metallurgy and Materials 2011年第6期18卷 691-694页

作者： Hong-bin tan School of Materials Science and Engineering Shaanxi University of Technology Hanzhong 723003 China

Long alumina fibers were prepared by sol-gel *** spinning sol was obtained by mixing aluminum nitrate,tartaric acid,and polyvinylpyrrolidone with a mass ratio of 10∶3∶***-differential scanning calorimetry （TG-DSC）,Fourier transform infrared （FT-IR） spectra,X-ray diffraction （XRD）,and scanning electron microscopy （SEM） were used to characterize the properties of the gel and ceramic fibers.A little of α-Al2O3 phase is observed in the alumina precursor gel fibers sintered at 1273 *** fibers with a uniform diameter can be obtained when sintered at 1473 K,and its main phase is also indentified as α-Al2O3.

关键词： alumina fibers sol-gel process polyvinylpyrrolidone

Interactive Training Model of TRIZ for Mechanical Engineers in China

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Chinese Journal of Mechanical Engineering 2014年第2期27卷 240-248页

作者： tan Runhua ZHANG Huangao National Technological Innovation Method and Tool Engineering Research Center Hebei University of Technology

Abstract： Innovation is a process of taking an original idea and converting it into a business value, in which the engineers face some inventive problems which can be solved hardly by experience. TRIZ, as a new theory for companies in China, provides both conceptual and procedural knowledge for finding and solving inventive problems. Because the government plays a leading role in the diffusion of TRIZ, too many companies from different industries are waiting to be trained, but the quantity of the trainers mastering TRIZ is incompatible with that requirement. In this context, to improve the training effect, an interactive training model of TRIZ for the mechanical engineers in China is developed and the implementation in the form of training classes is carried out. The training process is divided into 6 phases as follows： selecting engineers, training stage-l, finding problems, training stage-2, finding solutions and summing up. The government, TRIZ institutions and companies to join the programs interact during the process. The government initiates and monitors a project in form of a training class of TRIZ and selects companies to join the programs. Each selected companies choose a few engineers to join the class and supervises the training result. The TRIZ institutions design the training courses and carry out training curriculum. With the beginning of the class, an effective communication channel is established by means of interview, discussion face to face, E-mail, QQ and so on. After two years training practices, the results show that innovative abilities of the engineers to join and pass the final examinations increased distinctly, and most of companies joined the training class have taken congnizance of the power of TRIZ for product innovation. This research proposes an interactive training model of TRIZ for mechanical engineers in China to expedite the knowledge diffusion of TRIZ.

关键词： TR1Z interactive training model innovative abilities for mechanical engineers knowledge diffusion

Electrolyte Engineering Toward High-Voltage Aqueous Energy Storage Devices

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Energy & Environmental Materials 2021年第3期4卷 302-306页

作者： Jianfeng tan Jinping Liu School of Chemistry Chemical Engineering and Life Science and State Key Laboratory of Advanced Technology for Materials Synthesis and ProcessingWuhan University of TechnologyWuhan 430070China State Center for International Cooperation on Designer Low-carbon&Environmental Materials and School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China

Aqueous electrochemical energy storage(EES)devices are highly safe,environmentally benign,and inexpensive,but their operating voltage and energy density must be increased if they are to efficiently power multifunctional electronics,new-energy cars as well as to be used in smart *** Minireview summarizes the key breakthroughs and progress in expanding the electrochemical stability window(ESW)of aqueous EES devices over the past five *** briefly introducing the electrode engineering ways to widen ESW,we focus on four ground-breaking electrolyte engineering strategies and classify them into two kinds from the perspective of salts and exotic solutes/*** widening degree toward ESW of these emerging electrolytes is compared and the universal fundamental mechanism relating to the interactions between limited water molecules and high-concentration salts(or large amounts of exotic solutes/solvents)is *** challenges and perspectives for high-ESW electrolytes as well as recent advances in low-cost and other metal ion(sodium,potassium,zinc,etc.)-based electrolytes for expanding ESW are also outlined.

关键词： aqueous energy storage systems electrolyte engineering high voltage high-energy density water electrolysis

Max-margin non-negative matrix factorization with flexible spatial constraints based on factor analysis

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Frontiers of Computer Science 2016年第2期10卷 302-316页

作者： Dakun LIU Xiaoyang tan Department of Computer Science and Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

Non-negative matrix factorization （NMF） is a popular feature encoding method for image understanding due to its non-negative properties in representation, but the learnt basis images are not always local due to the lack of explicit constraints in its objective. Various algebraic or geometric local constraints are hence proposed to shape the behaviour of the original NMF. Such constraints are usually rigid in the sense that they have to be specified beforehand instead of learning from the data. In this paper, we propose a flexible spatial constraint method for NMF learning based on factor analysis. Particularly, to learn the local spatial structure of the images, we apply a series of transformations such as orthogonal rotation and thresholding to the factor loading matrix obtained through factor analysis. Then we map the transformed loading matrix into a Laplacian matrix and incorporate this into a max-margin non-negative matrix factorization framework as a penalty term, aiming to learn a representation space which is non-negative, discriminative and localstructure-preserving. We verify the feasibility and effectiveness of the proposed method on several real world datasets with encouraging results.

关键词： non-negative matrix factorization factor analysis loading matrix flexible spatial constraints

Recent progress and application on seismic isolation energy dissipation and control for structures in China

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Earthquake Engineering and Engineering Vibration 2018年第1期17卷 19-27页

作者： Zhou Fulin tan Ping Guangzhou University 248 Guangyuan Zhong Road Guangzhou 510405 China

China is a country where 100% of the territory is located in a seismic zone. Most of the strong earthquakes are over prediction. Most fatalities are caused by structural collapse. Earthquakes not only cause severe damage to structures, but can also damage non-structural elements on and inside of facilities. This can halt city life, and disrupt hospitals, airports, bridges, power plants, and other infrastructure. Designers need to use new techniques to protect structures and facilities inside. Isolation, energy dissipation and, control systems are more and more widely used in recent years in China. Currently, there are nearly 6,500 structures with isolation and about 3,000 structures with passive energy dissipation or hybrid control in China. The mitigation techniques are applied to structures like residential buildings, large or complex structures, bridges, underwater tunnels, historical or cultural relic sites, and industrial facilities, and are used for retrofitting of existed structures. This paper introduces design rules and some new and innovative devices for seismic isolation, energy dissipation and hybrid control for civil and industrial structures. This paper also discusses the development trends for seismic resistance, seismic isolation, passive and active control techniques for the future in China and in the world.

关键词： seismic isolation energy dissipation passive contro hybrid control