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Quantum Statistical Entropy of Spherical Black Holes in Higher Dimensions

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Chinese Physics Letters 2000年第10期17卷 705-707页

作者： XU Dian-Yan institute of microeletronics and Department of Computer Science and TechnologyPeking UniversityBeijing 100871

The free energy and entropy of a general spherically symmetry black hole are calculated by quantum statistic method with brick wall model Two different kinds of approximation are used to calculate the number of states in transverse spatial space. The final results are approximately equal except a rational numerical constant. The formulas of free energy and entropy, evaluated by each one of the two different kinds of approximation, are the same except some numerical constants. The free energy and entropy are dependent on the spacetime dimensionsD. When D = 4, they reduce to the usual well known results.

关键词： space. entropy dimensions

Different crystallinity of poly(d,l-lactide-co-p-dioxanone) copolymers acquired by control of chain microstructure

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Chinese Chemical Letters 2009年第12期20卷 1506-1509页

作者： Hui Zhen Zhao Jian Yuan Hao Cheng Dong Xiong Xian Mo Deng Chengdu institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 China School of microeletronics and Solid State Electronics University of Electronic Science and Technology of China Chengdu 610054 China Graduate School of Chinese Academy of Sciences Beijing 100039 China

Poly（d,l-lactide-co-p-dioxanone）（P（LA-co-PDO）） copolymers with different chain microstructures were synthesized by onestep or two-step bulk ring-opening polymerizations of d,l-lactide （LA） and p-dioxanone （PDO） monomers using stannous octoate [Sn（Oct）2]/n-dodecanol as the initiating system. The average sequence lengths of the lactidyl （LLA） and dioxanyl （LpDo） units were calculated from the ^1H NMR spectra. It was found that both LLA and Lpoo values from the two-step syntheses were significantly longer than those from the corresponding one-step syntheses, indicating more blocky structure achieved for the twostep copolymers. Corresponding to this difference in microstructure, the two-step copolymers were semi-crystalline, while the one-step copolymers were completely amorphous. In conclusion, the crystallinity of P（LA-co-PDO） copolymers could be adjusted conveniently to meet specific applications by changing the microstructure of the copolymers via different polymerization routes.

关键词： Poly(d,l-lactide-co-p-dioxanone) Copolymerization Chain microstructure Crystallinity

Synthesis of novel biodegradable poly(ethylene glycol) analogue:Water-soluble aliphatic polyester with pendant oligo(ethylene glycol) chains

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Chinese Chemical Letters 2009年第12期20卷 1502-1505页

作者： Lei Feng Jian Yuan Hao Cheng Dong Xiong Xian Mo Deng Chengdu institute of Organic Chemistry Chinese Academy of Sciences P.O. Box 415 Chengdu 610041 China School of microeletronics and Solid State Electronics University of Electronic Science and Technology of China Chengdu 610054 China Graduate School of Chinese Academy of Sciences Beijing 100039 China

A novel poly（ethylene glycol）（PEG） analogue composed of aliphatic polyester backbone and pendant oligo（ethylene glycol） short chains is reported. The PEG analogue is a copolymer synthesized by ring-opening alternating copolymerization of succinic anhydride with 2-（（2-（2-metho xyethoxy）ethoxy）methyl）oxirane. The structure of the copolymer was confirmed by ^1H NMR spectrum. The effects of the monomer feed ratio on the copolymerization were studied and the polymerization mechanism was given. The PEG analogue disclosed is water-soluble and expected to have promising applications in biomedical fields as a substitute of PEG due to the existence of degradable ester bond in the backbone.

关键词： Water-soluble PEG analogue 2-((2-(2-Methoxyethoxy)ethoxy)methyl)oxirane Ring-opening alternating copolymerization Polyester

High voltage-controlled magnetic anisotropy and interface magnetoelectric effect in sputtered multilayers annealed at high temperatures

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Science China(Physics,Mechanics & Astronomy) 2020年第7期63卷 114-119页

作者： LeZhi Wang Xiang Li Taisuke Sasaki Kin Wong GuoQiang Yu ShouZhong Peng Chao Zhao Tadakatsu Ohkubo Kazuhiro Hono WeiSheng Zhao KangLong Wang Beijing Advanced Innovation Center for Big Data and Brain Computing Beihang UniversityBeijing 100191China School of Computer Science&Engineering Beihang UniversityBejing 100191China Department of Electrical Engineering University of CaliforniaLos AngelesLos Angeles 90095USA School of microeletronics Beihang UniversityBeijing 100191China Inston IncLos Angeles 90095USA National institute for Materials Science(NIMS) Tsukuba 305-0047Japan institute of Microelectronics Chinese Academy of SciencesBejing 100029China

Voltage control of magnetism promises great energy efficiency in writing magnetic memory. Here, using Cr/Mo/CoFeB/MgO multilayers stable under high annealing temperatures up to 590°C, we significantly enhance the interfacial crystallinity, thereby the interface-originated perpendicular magnetic anisotropy(PMA), voltage-controlled magnetic anisotropy(VCMA), and interface magnetoelectric(ME) effect. High interfacial PMA of 1.35 mJ/m^2, VCMA coefficient of-138 fJ/(V m), and interface ME coefficient, which is 2-3 orders of magnitude larger than ab initio calculation results are simultaneously achieved after annealing at 500°C. These promising results enabled by the industry-applicable sputtering process will pave the way for highdensity voltage-controlled spintronic devices.

关键词： voltage-controlled magnetic anisotropy(VCMA) magnetoelectric(ME)effect perpendicular magnetic anisotropy

Feasibility study of the photonuclear reaction cross section of medical radioisotopes using a laser Compton scattering gamma source

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Nuclear Science and Techniques 2024年第9期35卷 168-177页

作者： Yu-Ning Gu Wei-Juan Zhao Xi-Guang Cao Yu-Xuan Yang Ting-Kai Ma Zheng-Li Liao Fei-Long Xu Yu-Gang Ma School of Physics and microeletronics Zhengzhou UniversityZhengzhou 450001China Shanghai Advanced Research institute Chinese Academy of SciencesShanghai 201210China Shanghai institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China School of Nuclear Science and Technology University of South ChinaHengyang 421001China Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China Shanghai Research Center for Theoretical Nuclear Physics NSFC and Fudan UniversityShanghai 200438China

In recent years,the gap between the supply and demand of medical radioisotopes has increased,necessitating new methods for producing medical *** reactions based on gamma sources have unique advantages in terms of producing high specific activity and innovative medical ***,the lack of experimental data on reaction cross sections for photonuclear reactions of medical radioisotopes of interest has severely limited the development and production of photonuclear transmutation medical *** this study,the entire process of the generation,decay,and measurement of medical radioisotopes was simulated using online gamma activation and offline gamma measurements combined with a shielding gamma-ray *** on a quasi-monochromatic gamma beam from the Shanghai Laser Electron Gamma Source(SLEGS),the feasibility of this measurement of production cross section for surveyed medi-cal radioisotopes was simulated,and specific solutions for measuring medical radioisotopes with ultra-low production cross sections were *** feasibility of this method for high-precision measurements of the reaction cross section of medical radioisotopes was demonstrated.

关键词： Medical radioisotope Photonuclear reaction GEANT4 Shanghai Laser Electron Gamma Source(SLEGS) Low-background gamma-ray spectrometer

Correction to:Feasibility study of the photonuclear reaction cross section of medical radioisotopes using a laser Compton scattering gamma source

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Nuclear Science and Techniques 2024年第11期35卷 244-244页

作者： Yu-Ning Gu Wei-Juan Zhao Xi-Guang Cao Yu-Xuan Yang Ting-Kai Ma Zheng-Li Liao Fei-Long Xu Yu-Gang Ma School of Physics and microeletronics Zhengzhou UniversityZhengzhou 450001China Shanghai Advanced Research institute Chinese Academy of SciencesShanghai 201210China Shanghai institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China School of Nuclear Science and Technology University of South ChinaHengyang 421001China Key Laboratory of Nuclear Physics and Ion‑beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China Shanghai Research Center for Theoretical Nuclear Physics NSFC and Fudan UniversityShanghai 200438China

Correction to:Nuclear Science and Techniques(2024)35:155 https://***/10.1007/s41365-024-01481-7 In Eq.(2)of this article,the term'i'should be denoted as a subscript,the corrected equation should read N_(0)=σ(E)N_(t)... 详细信息

关键词： corrected equation cross