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Correction value to charged Bekenstein-Hawking black hole entropy

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Science China(Physics,Mechanics & Astronomy) 2008年第9期51卷 1214-1220页

作者： zhang lichun WU YueQin ZHAO Ren Department of Physics Shanxi Datong UniversityDatong 037009China

Recently,based on the study of black hole Hawking radiation with the tunnel effect method,we found that the radiation spectrum of the black hole is not a strict pure thermal spectrum. It is a very interesting problem to determine how the departure of the black hole radiation spectrum from the pure thermal spectrum affects entropy. We calculate the partition function by the energy spectrum obtained using tunnel effect. Using the relation between the partition function and entropy,we derive the correction value to Bekenstein-Hawking entropy of the charged black hole. Fur-thermore,we obtain the conditions that various thermodynamic quantities must satisfy,when phase transition of the charged black hole occurs.

关键词： tunnel effect Bekenstein-Hawking entropy quantum statistics phase transition

ADAPTIVE CONTROLLER AND ITS APPLICATION IN FORCE SYSTEM OF ASYMMETRIC CYLINDER CONTROLLED BY SYMMETRIC VALVE

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Chinese Journal of Mechanical Engineering 2007年第6期20卷 50-53页

作者： WU Zhenshun zhang lichun ZHAO Chunlei School of Mechanical and Electrical Engineering Harbin Institute of Technology Harbin 150001 China

Partial pressure, system vibration and asymmetric system dynamic performance exit in asymmetric cylinder controller by symmetric valve hydraulic system. To solve this problem in the force control system, model reference adaptive controller is designed using equilibrium point stability theory and output error equation polynomial. The reference model is selected in such a way that it meets the system dynamic performance. Hardware configuration of asymmetric cylinder controlled by asymmetric valve hydraulic system is replaced by intelligent control algorithm, thus the cost is lowered and easy to application. Simulation results demonstrate that the proposed adaptive control sheme has good adaptive ability and well solves asymmetric dynamic performance problem. The designed adaptive controller is fairly robust to load disturbance and system parameter variation.

关键词： Asymmetric cylinder controlled by symmetric servo valve Model reference Balance point Adaptive control

Thermodynamics of the Reissner-Nordstrm-de Sitter black hole

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Science China(Physics,Mechanics & Astronomy) 2011年第8期54卷 1384-1387页

作者： zhang lichun LI HuaiFan ZHAO Ren Institute of Theoretical Physics Department of Physics Shanxi Datong University Datong 037009 China

Considering the relationship between the black hole horizon and the cosmological horizon, the thermodynamic property of the charged de Sitter spacetime is discussed. The effective temperature and energy are obtained. The result shows that the upper limit of the energy in the charged de Sitter spacetime is just the energy in the pure de Sitter spacetime. The thermal capacity of the charged de Sitter spacetime is positive, thus satisfying the thermal stability condition.

关键词： charged de Sitter spacetime Nernst theorem dark energy effective temperature

STABILIZATION OF A KIND OF PREY-PREDATOR MODEL WITH HOLLING FUNCTIONAL RESPONSE

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Journal of Systems Science & Complexity 2006年第3期19卷 436-440页

作者： Xi LIU Qingling zhang lichun ZHAO College of Science Northeastern University Shenyang 110006 China.

The stabilization problem of a kind of prey-predator model with Holling fimctional response is investigated. By approximate linearization approach, a feedback control law stabilizing the closed- loop system is obtained. On the other hand, by exact linearization approach, a suitable change of coordinates in the state space and a feedback control law render the complex nonlinear system to be a linear controllable one such that the positive equilibrium point of the closed-loop system is globally asymptotically stable.

关键词： Approximate linearization asymptotically stable exact linearization prey-predator model state feedback control.

Recent Advances in Graphitic Carbon Nitride-Based Chemiluminescence,Cataluminescence and Electrochemiluminescence

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Journal of Analysis and Testing 2017年第4期1卷 274-290页

作者： Hongjie Song lichun zhang Yingying Su Yi Lv College of Chemistry Sichuan UniversityChengdu 610064SichuanChina Analytical and Testing Center Sichuan UniversityChengdu 610064SichuanChina

Graphitic carbon nitride(g-C3N4)has attracted considerable attention due to its special structure and properties,such as its good chemical and thermal stability under ambient conditions,low cost and non-toxicity,and facile ***,g-C3N4-based sensors have been demonstrated to be of high interests in the areas of sensing due to the unique optical,electronic and catalytic properties of *** review focuses on the most salient advances in luminescent sensors based on g-C3N4,chemiluminescence,cataluminescence and electrochemiluminescence methods are *** review provides valuable information for researchers of related areas and thus may inspire the development of more practical and effective approaches for designing two-dimensional(2D)nanomaterial-assisted luminescent sensors.

关键词： Graphitic carbon nitride(g-C3N4) Chemiluminescence(CL) Cataluminescence(CTL) Electrochemiluminescence(ECL) Sensors

Function identification of miR159a,a positive regulator during poplar resistance to drought stress

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Horticulture Research 2023年第12期10卷 120-136页

作者： Tiantian Fu Chun Wang Yuzhang Yang Xiaoqian Yang Jing Wang lichun zhang Zeqi Wang Yanwei Wang State Key Laboratory of Tree Genetics and Breeding National Engineering Research Center of Tree Breeding and Ecological RestorationKey Laboratory of Genetics and Breeding in Forest Trees and Ornamental PlantsMinistry of EducationThe Tree and Ornamental Plant Breeding and Biotechnology Laboratory of National Forestry and Grassland AdministrationCollege of Biological Sciences and BiotechnologyBeijing Forestry UniversityBeijing 100083China

Drought seriously affects the growth and development of ***159 is a highly conserved and abundant microRNA family that plays a crucial role in plant growth and stress ***,studies of its function in woody plants are still ***,the expression of miR159a was significantly upregulated after drought treatment in poplar,and the overexpression of miR159a(OX159a)significantly reduced the open area of the stomata and improved water-use efficiency in *** drought treatment,OX159a lines had better scavenging ability of reactive oxygen species and damage of the membrane system was less than that in wild-type *** was the target gene of miR159a,as verified by psRNATarget prediction,RT-qPCR,degradome sequencing,and 5′rapid amplification of cDNA ends(5′RACE).Additionally,miR159a-short tandem target mimic suppression(STTM)poplar lines showed increased sensitivity to drought *** analysis comparing OX159a lines with wild-type lines revealed upregulation of a series of genes related to response to water deprivation and metabolite ***,drought-responsive miR172d and miR398 were significantly upregulated and downregulated respectively in OX159a *** investigation demonstrated that miR159a played a key role in the tolerance of poplar to drought by reducing stomata open area,increasing the number and total area of xylem vessels,and enhancing water-use efficiency,and provided new insights into the role of plant miR159a and crucial candidate genes for the molecular breeding of trees with tolerance to drought stress.

关键词： poplar breeding drought

PHASE TRANSFOR MATION INDUCED BY DEFORMATION IN TiAl(Cr)INTERMETALLICS AT ROOM TEMPERATURE

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中国有色金属学会会刊:英文版 1999年第S1期9卷 65-68页

作者： Lianlong He Rong Yu lichun zhang Huayong Pan Hengqiang Ye Laboratory of Atomic Imaging of Solids Institute of Metal ResearchChinese Academy of SciencesShenyang 110015China Department of Material Science Science and TechnologyUniver si ty of Beij ingBeijing 100083China

The phase transformation induced by deformation in TiAl(Cr) intermetallics at room temperature has been studied by means of TEM and HREM observations and nanoprobe analysis. The results showed that, twinning is a primary deformation mechanism at room temperature, when plastic deformation is small twinning takes place on {111} planes and when plastic deformation is great two sets twins takes place usually from intersection region, where the atomic structure changes to hexagonal structure with the composition of Ti 55.7 2Al 42.2 8Cr 1.7 .

关键词： TiAl(Cr) phase transformation deformation structural evolution

An Improved Analytical Model for Minority Carrier Transport in Quasi-Neutral Semiconductor Regions

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Journal of Semiconductors 1998年第3期 3-5页

作者： Ma Pingxi, zhang lichun, Zhao Baoying and Wang Yangyuan(Institute of Microelectronics, Peking University, Beijing 100871)

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关键词： An Improved Analytical Model for Minority Carrier Transport in Quasi-Neutral Semiconductor Regions

CHARACTERIZATION OF REFRACTORY METAL NITRIDE SCHOTTKY CONTACTS ON GaAs

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CHARACTERIZATION OF REFRACTORY METAL NITRIDE SCHOTTKY CONTAC...