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A Fluctuation Type limit Theorem for Ji(?)ina Processes with Immigration

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Acta Mathematica Sinica,English Series 2009年第8期25卷 1379-1388页

作者： Yu Qiang li School of Finance and Statistics East China Normal University Shanghai 200241 P. R. China

It is proved by the theory of semigroup that the Ornstein-Uhlenbeck type process with jumps can arise from the fluctuation limit of a sequence of Jirina processes with immigration under suitable moments conditions.

关键词： Jirina process with immigration fluctuation limit Ornstein-Uhlenbeck type process

Biochemical and microbial properties of rhizospheres under maize/ peanut intercropping

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Journal of Integrative Agriculture 2016年第1期15卷 101-110页

作者： li Qi-song Key Laboratory of Biopesticide and Chemical Biology Ministry of Education/College of Life Sciences Fujian Agriculture and Forestry University Fuzhou 350002 P.R.China Agroecological Institute Fujian Agriculture and Forestry University Fuzhou 350002 P.R.China Department of Horticulture Pir Mehr Ali Shah Arid Agriculture University Rawalpindi 46300 Pakistan

Maize/peanut intercropping system shows the significant yield advantage. Soil microbes play major roles in soil nutrient cycling and were affected by intercropping plants. This experiment was carried out to evaluate the changing of rhizosphere microbial community composition, and the relationship between microbial community and soil enzymatic activities, soil nutrients in maize/peanut intercropping system under the following three treatments： maize （Zea mays L.） and peanut （Arachis hypogaea L.） were intercropped without any separation （NS）, by half separation （HS） using a nylon net （50 μm） and complete separation （CS） by using a plastic sheet, respectively. The soil microbial communities were assessed by phospholipid fatty acid （PLFA）. We found that soil available nutrients （available nitrogen （Avail N） and available phosphorus （Avail P）） and enzymatic activities （soil urase and phosphomonoesterase） in both crops were improved in NS and HS treatments as compared to CS. Both bacterial and fungal biomasses in both crops were increased in NS followed by HS. Furthermore, Gram-positive bacteria （G＋） in maize soils were significant higher in NS and HS than CS, while the Gram-negative （G-） was significant higher in peanut soil. The ratio of normal saturated to monounsaturated PLFAs was significantly higher in rhizosphere of peanut under CS treatment than in any other treatments, which is an indicator of nutrient stress. Redundancy analysis and cluster analysis of PLFA showed rhizospheric microbial community of NS and HS of both plants tended to be consistent. The urase and Avail N were higher in NS and HS of both plants and positively correlated with bacteria, fungi （F） and total PLFAs, while negatively correlated with G＋/G- and NS/MS. The findings suggest that belowground interactions in maize/peanut intercropping system play important roles in changing the soil microbial composition and the dominant microbial species, which was closely related with the improving of soil

关键词： maize/peanut intercropping phospholipid fatty acid soil nutrient soil enzymes

Approximation Theorems and Fixed Point Theorems for Various Classes of 1-set-contractive Mappings in Banach Spaces

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Acta Mathematica Sinica,English Series 2001年第1期17卷 103-112页

作者： li Shan liU Department of Mathematics Qufu Normal University

In this paper, we will prove that Ky Fan’s Theorem (Math. Z. 112(1969), 234-240) is true for 1-set-contractive maps defined on a bounded closed convex subset K in a Banach space with int K≠ . This class of 1-set-contractive maps includes condensing maps, nonexpansive maps, semicontractive maps, LANE maps and others. As applications of our theorems, some fixed point theorems of non-self- maps are proved under various well-known boundary conditions. Our results are generalizations and improvements of the recent results obtained by many authors.

关键词： Approximation theorems Fixed point theorems 1-set-contractive maps Semicontractive maps LANE maps

Distributed parametric modeling and simulation of light polarization states using magneto-optical sensing based on the Faraday effect

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Science China(Technological Sciences) 2016年第12期59卷 1899-1910页

作者： li Yan Song liU Jun CAO li Xin liu Qi Zhi School of Electrical and Electronic Engineering North China Electric Power University

To solve the problems encountered in practical processes of magneto-optical sensing, the infinitesimal distributed-parameter model and finite-element accumulation of different dielectric properties of micromaterials were used to describe the evolution of light polarization states, instead of the previously commonly used method of lumped-parameter simulation, thus essentially explaining the mechanism of sensing, magneto-optical effects, and related factors, and achieving multiphysics coupling using the COMSOL finite-element analysis method. Considering the cases of the Faraday effect without and with line birefringence, the magneto-optical effect and output characteristics of an infinitesimal magneto-optical sensor were simulated and studied. The results verified the effectiveness of the infinitesimal sensor model. Because the magnetic field, stress, and temperature changes alter the dielectric properties of magneto-optical materials, the finite-element accumulation method lays a good foundation for research on theoretical analysis and performance of magneto-optical sensors affected by factors such as the magnetic field, temperature, and stress.

关键词： magneto-optical sensor Faraday effect linear birefringence infinitesimal distributed-parameter model multi-physics coupling COMSOL

Density Functional Theory Investigation on the Reaction Mechanisms of Ti(^3F)with CH2Cl2 and CHCl3 to CH2=TiCl2 and HC÷TiCl3

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Chinese Journal of Structural Chemistry 2016年第2期35卷 193-198页

作者： CHENG Xue-li (School of Chemistry and Chemical Engineering Taishan UniversityTai'anShandong 271021China

The reaction mechanisms of Ti（~3F）＋ CH2C12→CH2=TiCl2 and Ti（~3F）＋ CHC13→HC÷TiCl3 were investigated with Gaussian 03 program package at the B3PW91/6-311＋＋G（d,p）*** computational results revealed that：1） Both reaction systems are initiated by Ti（~3F） atom attacking the C atom of CH2C12 and CHCl3 to activate a C-Cl bond;2） Both reaction systems were carried out via triplet reaction channels;3） CH2=TiCl2 has singlet and triplet isomers,and the singlet one is more stable;4） The HOMO of CH2=TiCl2（S） illustrates a π-bonding interaction between C and Ti;5） Only singlet HC÷TiCl3 was located,and the Mulliken atomic spin densities show that the two single electrons are mostly on the C atom.

关键词： B3PW91 reaction mechanism Ti(~3F) CH2=TiCl2 HOTiCl3

Effects of polar cortical cytoskeleton and unbalanced cortical surface tension on intercellular bridge thinning during cytokinesis

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Acta Mechanica Sinica 2011年第6期27卷 1081-1090页

作者： li Wang Mei-Wen An Xiao-Na li Fang Yang Yang liu Institute of Applied Mechanics and Biomedical Engineering Taiyuan University of Technology 030024 Taiyuan China

To probe the contributions of polar cortical cytoskeleton and the surface tension of daughter cells to intercellular bridge thinning dynamics during cytokinesis,we applied cytochalasin D（CD） or colchicine（COLC） in a highly localized manner to polar regions of dividing normal rat kidney（NRK） *** observed cellular morphological changes and analyzed the intercellular bridge thinning trajectories of dividing cells with different polar cortical *** blebbistatin（BS） application was used to obtain cells losing active contractile force *** results show that locally released CD or colchicine at the polar region caused inhibition of cytokinesis before *** treatment at phases after ingression allowed completion of cytokinesis but dramatically influenced the trajectories of intercellular bridge *** single polar cortical actin induced transformation of the intercellular bridge thinning process,and polar cortical tension controlled deformation time of intercellular *** study provides a feasible framework to induce and analyze the effects of local changes in mechanical properties of cellular components on single cellular cytokinesis.

关键词： Cytokinesis Normal rat kidney epithelial cells Intercellular bridge Polar cortical cytoskeleton - Cortical surface tension

Progress in organic photocatalysts

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Rare Metals 2018年第1期37卷 1-12页

作者： Ying-Zhi Chen Wen-Hao li ling li Lu-Ning Wang School of Materials Science and Engineering University of Science and Technology Beijing State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing

Organic materials have advantages of diversity,ease of functionality, self-assembly, etc. The varied mechanistic pathways also make it conceivable to design an appropriate photocatalyst for an identical reaction. From this perspective, organic photocatalysts find wide applications in homogeneous, heterogeneous photocatalysis and photoelectrochemical（PEC） solar cells. In this review, the form of the employed organic photocatalysts ranging from molecules, supported molecules, to nanostructures or thinfilm aggregates will be firstly discussed. Rational design strategies relating to each form are also provided, aiming to enhance the photoenergy conversion efficiency. Finally,the ongoing directions for future improvement of organic materials in high-quality optoelectronic devices are also proposed.

关键词： Organic photocatalysts Homogeneous photocatalysis Heterogenization Organic nanostructures Photoelectrochemical water splitting

Subcategories of Fixed Points of Mutations by Exceptional Objects in Triangulated Categories

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Acta Mathematica Sinica,English Series 2016年第2期32卷 187-198页

作者： li Dan TANG College of Mathematics and Computer Science Fuzhou University

We first prove that the subcategory of fixed points of mutation determined by an excep- tional object E in a triangulated category coincide with the perpendicular category of E. Based on this characterisation, we prove that the subcategory of fixed points of mutation in the derived category of the coherent sheaves on weighted projective line with genus one is equivalent to the derived category of a hereditary algebra. Meanwhile, we induce two new recollements by left and right mutations from a given recollement.

关键词： Subcategory of fixed points exceptional object recollement

Inferring rules for adverse load combinations to crack in concrete dam from monitoring data using adaptive neuro-fuzzy inference system

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Science China(Technological Sciences) 2012年第1期55卷 136-141页

作者： XUHongZhong li XueHong College of Transportation Science and Engineering Nanjing University of Technology Nanjing 210009 China

The formation and growth of cracks in concrete dams are mainly induced by hydrostatic and temperature *** cracks es-pecially unstable cracks are of great danger to the safety of dams,it is critical to avoid extremely adverse load combinations during the dam operations to achieve the stability of ***,the adverse load combinations have to be deter-mined empirically by experts based on specific dam site ***,it is attractive to apply quantitative instead of empirical methods to identify the adverse loading *** this study,we employ an adaptive neuro-fuzzy inference sys-tem(ANFIS) to Chencun concrete *** ANFIS is able to help us build a relationship between the model inputs(reservoir water level and air temperature) and the model output(crack opening displacement).Based on this relationship,the rules of the adverse load combinations to the crack are generated directly from the monitoring *** accuracy of the trained ANFIS is proved by comparing the modeling results and the monitoring *** work demonstrates that the ANFIS is a useful ap-proach for accurately recognizing the rules of the adverse load combinations that can be used in the knowledge base of dam safety expert system.

关键词： crack concrete dam load combination adaptive neuro-fuzzy inference system rules