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Improved Hrmander’s Theorem and New Methods for Oscillatory Integral Operators

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Acta Mathematica Sinica,English Series 2009年第11期25卷 1865-1874页

作者： sheng-ming MA LMIB and School of Mathematics and System Sciences Beihang University Beijing 100083 P. R. China

This paper proves a theorem on the decay rate of the oscillatory integral operator with a degenerate C^∞ phase function, thus improving a classical theorem of HSrmander. The proof invokes two new methods to resolve the singularity of such kind of operators： a delicate method to decompose the operator and balance the L^2 norm estimates; and a method for resolution of singularity of the convolution type. The operator is decomposed into four major pieces instead of infinite dyadic pieces, which reveals that Cotlar＇s Lemma is not essential for the L^2 estimate of the operator. In the end the conclusion is further improved from the degenerate C^∞ phase function to the degenerate C^4 phase function.

关键词： oscillatory integral operators decay rate Fourier integral operators degenerate phase resolution of singularity

Fuzzy Topology Based on Residuated Lattice-Valued Logic

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Acta Mathematica Sinica,English Series 2001年第1期17卷 89-102页

作者： ming sheng YING State Key Laboratory of Intelligent Technology and Systems Department of Computer Science and Technology Tsinghua University

We use a semantical method of complete residuated lattice-valued logic to give a general- ization of fuzzy topology as a partial answer to a problem by Rosser and Turquette.

关键词： Fuzzy topology Residuated lattice Many-valued logic Semantics

Optimal Policies for Quantum Markov Decision Processes

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International Journal of Automation and computing 2021年第3期18卷 410-421页

作者： ming-sheng Ying Yuan Feng sheng-Gang Ying Centre for Quantum Software and Information University of Technology SydneyNSW 2007Australia State Key Laboratory of Computer Science Institute of SoftwareChinese Academy of SciencesBeijing 100190China Department of Computer Science and Technology Tsinghua UniversityBeijing 100084China

Markov decision process(MDP)offers a general framework for modelling sequential decision making where outcomes are *** particular,it serves as a mathematical framework for reinforcement *** paper introduces an extension of MDP,namely quantum MDP(q MDP),that can serve as a mathematical model of decision making about quantum *** develop dynamic programming algorithms for policy evaluation and finding optimal policies for q MDPs in the case of *** results obtained in this paper provide some useful mathematical tools for reinforcement learning techniques applied to the quantum world.

关键词： Quantum Markov decision processes quantum machine learning reinforcement learning dynamic programming decision making

Structural and Optical Characteristics of InGaN／GaN Multi-Quantum Wells Grown on α-and c-Plane Sapphire Substrates

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Chinese Physics Letters 2004年第7期21卷 1323-1326页

作者： YUHong-Bo CHENHong LIDong-sheng ZHOUJun-ming StateKeyLaboratoryforSurfacePhysics InstituteofPhysicsChineseAcademyofSciencesPOBox603Beijing100080

We investigate the structural and optical properties of InGaN-based multi-quantum wells grown on a–c plane sapphire substrates by atomic force microscopy, high-resolution x-ray diffraction and temperature-dependent photoluminescence measurements. The multi-quantum wells grown on a-plane sapphire substrate show stronger exciton localization effect compared with that grown on the c-plane substrate, although the threading dislocation densities in the two samples are almost the same. We attribute the results to the different in-plane strain of quantum well grown on different substrate orientations at the same growth temperature. Since the exciton localization effect plays a key role to obtain high efficiency InGaN-based optoelectronics devices, the presented result should be emphasized.

关键词： Strain

Focusing of Spherical Nonlinear Pulses for Nonlinear Wave Equations

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Acta Mathematicae Applicatae Sinica 2005年第3期21卷 415-428页

作者： ming-sheng Yuan Department of Mathematics Shanghai Jiaotong University Shanghai 200240 China

This paper describes the behavior of spherical pulse solutions of a system of semilinear wave equations in three space variables. Away fi＇om the focal point, we describe solutions with nonlinear geometric optics. We show that the approximation given by nonlinear geometric optics is valid before and after the focal point. We obtain a global asymptotic description including an approximation which is a solution of the linear wave equations near the caustic.

关键词： Nonlinear wave equations spherical pulses focusing

Enhanced leaching of metals from spent lithium-ion batteries by catalytic carbothermic reduction

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Rare Metals 2023年第8期42卷 2688-2699页

作者： Ying-Chao Zhang Wen-Hao Yu sheng-ming Xu Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China China National Petroleum&Chemical Planning Institute Beijing 100013China Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education Tsinghua UniversityBeijing 100084China Beijing Key Lab of Fine Ceramics Tsinghua UniversityBeijing 100084China

Spent Li-ion battery(LIB)recycling has become a challenge with the rapidly developing electric vehicle(EV)*** address the problems of high cost and low recovery of Li in the recycling of spent LIBs using traditional hydrometallurgical processes,we developed an alkali metal catalytic carbothermic reduction method to recover spent LiNi_(x)Co_(y)Mn_(z)O_(2)(NCM).Using alkali metal catalysts,such as NaOH,significantly reduced the temperature required for carbothermic NCM material reduction and realized targeted control of the phase of the reduction product,where Li was first separated by prior water leaching,followed by Ni,Co,and Mn recycling by acid *** optimized carbothermic reduction conditions were a reaction time of 3 h,temperature of 550℃,NaOH dosage of 15 wt%,and graphite dosage of 15 wt%.The Li leaching efficiency reached 78.5 wt%during water *** during acid leaching,the Ni,Co and Mn leaching efficiencies were 99.8 wt%,99.7 wt%,and 99.5wt%,*** study provides strong technical support for the development of LIB industry.

关键词： Spent lithium-ion battery(LIB) Battery recycling Leaching Lithium recovery Alkali metal catalytic carbothermic reduction

Efficient generation of relativistic near-single-cycle mid-infrared pulses in plasmas

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Light(Science & Applications) 2020年第1期9卷 1581-1589页

作者： Xing-Long Zhu Su-ming Weng Min Chen Zheng-ming sheng Jie Zhang Key Laboratory for Laser Plasmas(MOE) School of Physics and AstronomyShanghai Jiao Tong University200240 ShanghaiChina Collaborative Innovation Center of IFSA Shanghai Jiao Tong University200240 ShanghaiChina SUPA Department of PhysicsUniversity of StrathclydeGlasgow G40NGUK Cockcroft Institute Sci-Tech DaresburyCheshire WA44ADUK Tsung-Dao Lee Institute 200240 ShanghaiChina Institute of Physics Chinese Academy of Sciences100190 BeijingChina

Ultrashort intense optical pulses in the mid-infrared(mid-IR)region are very important for broad applications ranging from super-resolution spectroscopy to attosecond X-ray pulse generation and particle ***,currently,it is still difficult to produce few-cycle mid-IR pulses of relativistic intensities using standard optical ***,we propose and numerically demonstrate a novel scheme to produce these mid-IR pulses based on laser-driven plasma optical *** this scheme,a plasma wake is first excited by an intense drive laser pulse in an underdense plasma,and a signal laser pulse initially at the same wavelength(1 micron)as that of the drive laser is subsequently injected into the plasma *** signal pulse is converted to a relativistic multi-millijoule near-singlecycle mid-IR pulse with a central wavelength of ~5 microns via frequency-downshifting,where the energy conversion efficiency is as high as approximately 30% when the drive and signal laser pulses are both at a few tens of millijoules at the *** scheme can be realized with terawatt-class kHz laser systems,which may bring new opportunities in high-field physics and ultrafast science.

关键词： relativistic cycle scheme

Extraction kinetics of zinc by new extractant in ammoniacal system

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Journal of Central South University 2013年第7期20卷 1797-1804页

作者： HUANG Ling HE Jing CHEN Yong-ming YANG sheng-hai JIN sheng-ming TANG Mo-tang School of Metallurgical Science and Engineering Central South University Changsha 410083 China Guangzhou Research Institute of Non-ferrous Metals Guangzhou 510000 China

The controlling step and the extraction reaction rate equation of zinc extraction from Zn（II）-NH3 solution by using a newly synthesized organic compound, 2-acetyl-3-oxo-dithiobutyric acid-myristyl ester as the zinc extractant, were clarified. The effects of agitation speed, specific interfacial area, temperature, extractant concentration and Zn ion concentration on the extraction rate are studied in constant interfacial area cell. The results show that the extraction rate depends on interfacial chemical reaction and diffusion by using this new extraetant to extract zinc, and the apparent activation energy of this extraction reaction is measured as 28.2 kJ/mol, which demonstrates that the extraction reaction is controlled by the mixed-controlled reaction rate. The apparent reaction orders a and b are measured as 1 and 0.38, and the constant k0 is 138.70. So, when extraction conditions are controlled as [HR]=20%-50%, T=0-30℃, N=120-177 r/min and S=72.6-127.5 m-1, the solvent extraction reaction rate can be depicted as v/（mol . m-2 . s-1 ） = 138.7. exp（ - 28 206/8.314T ）. [Zn 2＋ ]r ·[HR ]o0.38.

关键词： solvent extraction zinc 2-acetyl-3-oxo-dithiobutyric acid-myristyl ester kinetics

Projects Funded by the Division of Botany （NSFC） in 2005： Retrospect and Prospect

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Journal of Integrative Plant Biology 2005年第12期47卷 1516-1527页

作者： ming-Zhang WEN Yue CHEN Qin-Li WANG sheng-ming DU Department of Life Sciences National Natural Science Foundation of China Beijing 100083 China Institute of Botany the Chinese Academy of Sciences Beijing 100093 China

The present paper briefly introduces information about proposals received and funded, statistics and analysis of evaluation of peer review, and supporting strategies and reforms in program reviewing and administration in the Division of Botany at the Natural Science Foundation of China （NSFC） in 2005. A list of general programs and the abstract of key programs funded by this Division in 2005 are also provided.

关键词： Division of Botany fund project review.