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Chinese Physics B 2011年第12期20卷 52-56页

作者：桑明煌余子星李翠翠涂凯 department of Physics Jiangxi Normal University

For the conventional translational shape-invariant potentials （TSIPs）, it has demonstrated that the phase contribution devoted by the scattered subwaves in the analytical transfer matrix quantization condition is integrable and independent of n. Based on this fact we propose a novel strategy to generate the whole set of conventional TSIPs and classify them into three types. The generating functions are given explicitly and the Morse potential is taken as an example to illustrate this strategy.

关键词： translational shape-invariant potentials supersymmetric quantum mechanics analyticaltransfer matrix method scattered subwaves generating function

Michael Additions of Activated Methylene Compounds to α,β-Unsaturated Esters Promoted by Samarium (Ⅲ) Iodide

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Chinese Chemical Letters 2000年第6期11卷 483-484页

作者： Xiao Yuan CHEN Wei Liang BAO Yong Min ZHANG (department of Chemistry, Zhejiang University at Xixi Campus, Hangzhou 310028)department of Chemistry Hunan Jishou University, Hunan Jishou 416000) department of Chemistry Zhejiang University at Xixi Campus department of Chemistry Hunan Jishou University

Promoted by SmI3 β -diketones， β-ketoesters and α -cyano esters were added to α,β -unsaturated esters to form δ-carbonyl esters in mild conditions in moderate to good yields.

关键词： Samarium Michael addition α,β-unsaturated ester,β-diketones,δ-carbonyl esters

Teleporting a quantum controlled-Not with one target/two targets gate using two partially entangled states

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Chinese Physics B 2009年第1期18卷 30-34页

作者：陈立冰金锐博路洪 department of Photoelectron and Physics Foshan University

This paper considers the teleportation of quantum controlled-Not （CNOT） gate by using partially entangled states. Different from the known probability schemes, it presents a method for teleporting a CNOT gate with unit fidelity and unit probability by using two partially entangled pairs as quantum channel. The method is applicable to any two partially entangled pairs satisfying the condition that their smaller Schmidt coefficients μ and ν are （2μ ＋ 2ν - 2μν - 1） ≥ 0. In this scheme, the sender＇s local generalized measurement described by a positive operator valued measurement （POVM） lies at the heart. It constructs the required POVM. It also puts forward a scheme for teleporting a CNOT with two targets gate with unit fidelity by using same quantum channel. With assistance of local operations and classical communications, three spatially separated users are able to complete the teleportation of a CNOT with two targets gate with probability of （2μ ＋ 2ν - 1）. With a proper value of μ and ν, the probability could reach nearly 1.

关键词： partially entangled state teleportation CNOT gate positive operator valued measurement

Enhancement of 1.54 μm emission in Er:LiNbO_3 crystal by codoping with Zn^(2+) ions

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Journal of Rare Earths 2012年第1期30卷 25-28页

作者：钱艳楠王锐徐超邢丽丽徐衍岭杨春辉 department of Chemistry Harbin Institute of Technology

The enhanced intensity and lengthened lifetime of 1.54 μm emission were observed for Er：LiNbO3 crystal codoped with Zn2＋ *** ZnO codoping led to the reduction of the green upconversion emission in Er：LiNbO3 *** decay trace of the 4S3/2→4I15/2 was ob-viously nonexponential for Er：LiNbO3 codoped with 0 and 3 mol.% ZnO,but became exponential for one codoped with 6 mol.% *** OH-absorption spectra showed after codoping with Zn2＋ ions,the OH-absorption peaking position shifted from ~3495 to 3484 cm-1,and the absorption cross section *** spectroscopic characteristics suggested that the improvement of 1.54 μm emission was attributed to the reduction of Er3＋ cluster sites.

关键词： 1.54 μm emission Zn2+ Er3+ cluster site rare earths

Global weirding at mass extinction horizons

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National Science Review 2024年第1期11卷 10-12页

作者： Gregory J.Retallack department of Earth Sciences University of Oregon

A strong motivation for studying mass extinctions is understanding how current climatic and biodiversity crises will affect creatures living on land such as ourselves. Perhaps the question is: how bad can it get? In that case, terrestrial Permian-Triassic mass extinctions are an irresistible worst-case scenario [1].

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Flow imbalance in MHD flows in splitting ducts with locally different electric conductivities of the walls

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Journal of Hydrodynamics 2018年第5期30卷 920-927页

作者： Yang Luo Mengqi Zhu C.N.Kim department of Mechanical Engineering Graduate School Kyung Hee University department of Mechanical Engineering College of Engineering Kyung Hee University

In this study, three-dimensional liquid-metal magnetohydrodynamic splitting flows in a duct with one inflow channel and two outflow channels with locally different wall electric conductivities（different conductance ratios） are computationally examined. The numerical calculation is achieved with the use of CFX code, with a structured grid system chosen after a series of mesh independence tests. The detailed features of the MHD flows are depicted in a case where the electric conductivities of the two outflow ducts are quite different. Also, the interdependency among the current, fluid velocity, pressure and electric potential is elucidated in order to describe the electromagnetic characteristics of the liquid-metal flows. The result shows that the imbalance of the mass flow rate in the two outflow channels strongly depends on the wall conductivity（i.e., conductance ratio） of each outflow channel.

关键词： Liquid metal flow splitting duct flow imbalance numerical examination conductance ratio

Probabilistic Automata-Based Method for Enhancing Performance of Deep Reinforcement Learning Systems

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IEEE/CAA Journal of Automatica Sinica 2024年第11期11卷 2327-2339页

作者： Min Yang Guanjun Liu Ziyuan Zhou Jiacun Wang the department of Computer Science Tongji University IEEE the Computer Science and Software Engineering department Monmouth UniversityWest Long Branch

Deep reinforcement learning(DRL) has demonstrated significant potential in industrial manufacturing domains such as workshop scheduling and energy system ***, due to the model's inherent uncertainty, rigorous validation is requisite for its application in real-world tasks. Specific tests may reveal inadequacies in the performance of pre-trained DRL models, while the “black-box” nature of DRL poses a challenge for testing model behavior. We propose a novel performance improvement framework based on probabilistic automata,which aims to proactively identify and correct critical vulnerabilities of DRL systems, so that the performance of DRL models in real tasks can be improved with minimal model ***, a probabilistic automaton is constructed from the historical trajectory of the DRL system by abstracting the state to generate probabilistic decision-making units(PDMUs), and a reverse breadth-first search(BFS) method is used to identify the key PDMU-action pairs that have the greatest impact on adverse outcomes. This process relies only on the state-action sequence and final result of each trajectory. Then, under the key PDMU, we search for the new action that has the greatest impact on favorable results. Finally, the key PDMU, undesirable action and new action are encapsulated as monitors to guide the DRL system to obtain more favorable results through real-time monitoring and correction mechanisms. Evaluations in two standard reinforcement learning environments and three actual job scheduling scenarios confirmed the effectiveness of the method, providing certain guarantees for the deployment of DRL models in real-world applications.

关键词： Deep reinforcement learning(DRL) performance improvement framework probabilistic automata real-time monitoring the key probabilistic decision-making units(PDMU)-action pair

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Enhancement of thermal rectification by asymmetry engineering of thermal conductivity and geometric structure for multi-segment thermal rectifier

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Chinese Physics B 2023年第6期32卷 34-43页

作者：杜甫烨张望王惠琼郑金成 department of Physics Xiamen UniversityXiamen 361005China department of Physics Xiamen University Malaysia439000 SepangSelangorMalaysia

Thermal rectification is an exotic thermal transport phenomenon,an analog to electrical rectification,in which heat flux along one direction is larger than that in the other direction and is of significant interest in electronic device ***,achieving high thermal rectification efficiency or rectification ratio is still a scientific *** this work,we performed a systematic simulation of thermal rectification by considering both efforts of thermal conductivity asymmetry and geometrical asymmetry in a multi-segment thermal *** is found that the high asymmetry of thermal conductivity and the asymmetry of the geometric structure of multi-segment thermal rectifiers can significantly enhance the thermal rectification,and the combination of both thermal conductivity asymmetry and geometrical asymmetry can further improve thermal rectification *** work suggests a possible way for improving thermal rectification devices by asymmetry engineering.

关键词： thermal conductivity simulation thermal rectification multi-segment thermal rectifier

Dual-compressed photoacoustic single-pixel imaging

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National Science Review 2023年第1期10卷 187-195页

作者： Yuning Guo Baowen Li Xiaobo Yin department of Mechanical Engineering University of Colorado department of Material Science and Engineering Department of Physics Shenzhen Institute for Quantum Science and Engineering Southern University of Science and Technology Materials Science and Engineering Program University of Colorado

Photoacoustic imaging,an acoustic imaging modality with potentially optical resolution in an optical turbid medium,has attracted great ***,the convergence of wavefront optimization and raster scanning in computational photoacoustic imaging leads to the challenge of fast mapping,especially for a spatial resolution approaching the acoustic deep-subwavelength *** a sparse sampling paradigm,compressive sensing has been applied in numerous fields to accelerate data acquisition without significant quality *** this work,we propose a dual-compressed approach for photoacoustic surface tomography that enables high-efficiency imaging with 3D spatial resolution unlimited by the acoustics in a turbid *** dual-compressed photoacoustic imaging with single-pixel detection,enabled by spatially optical modulation with synchronized temporally photoacoustic coding,allows decoding of the fine optical information from the modulated acoustic signal even when the variance of original photoacoustic signals is *** perform a proof-of-principle numerical demonstration of dual-compressed photoacoustic imaging, that resolves acoustic sub-acoustic-wavelength details with a significantly reduced number of measurements,revealing the potential for dynamic *** dual-compressed concept,which transforms unobtrusive spatial difference into spatio-temporal detectable information,can be generalized to other imaging modalities to re alize efficient,high-spatial-resolution imaging.

关键词： photoacoustic imaging compressive sensing single-pixel imaging surface tomography

Slow light propagation without absorption based on intersubband transitions in a semiconductor quantum well

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Optoelectronics Letters 2012年第5期8卷 397-400页

作者：韩定安曾亚光白艳峰 department of Physics Foshan University department of Physics Southeast University

When semiconductor quantum wells(SQWs) interact with lasers,the group velocity of the low-intensity light pulse is studied *** is shown that by adjusting the parameters,slow light propagation of the probe field can be exhibited in such a ***,the probe absorption-gain spectra can be changed from absorption to zero,i.e.,electromagnetically induced transparency(EIT).It is easy to observe the light propagation experimentally,and it leads to potential applications in many fields of solid-state quantum information,for example,optical switching,detection and quantum computing.

关键词： Probes Quantum computers Quantum optics Semiconductor quantum wells