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New extended method for ψ' scaling function of inclusive electron scattering

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Science China(physics,Mechanics & Astronomy) 2023年第10期66卷 53-61页

作者： Lei Wang Qinglin Niu Jinjuan Zhang Jian Liu Zhongzhou Ren School of physics Science and Engineering Tongji UniversityShanghai 200092China College of Science China University of Petroleum(East China)Qingdao 266580China College of Electronic and Information Engineering Shandong University of Science and TechnologyQingdao 266590China Laboratory of High Precision Nuclear Spectroscopy Insititute of Modern PhysicsChinese Academy of SciencesLanzhou 730000China Guangxi Key Laboratory of Nuclear physics and Nuclear Technology Guangxi Normal UniversityGuilin 541004China Key Laboratory of Advanced Micro-Structure Materials Ministry of EducationShanghai 200092China

Scaling analyses have been successfully applied to study the inclusive electron scattering(e, e') over the past few decades. In this study, we utilize the ψ' scaling function in momentum space to analyze the(e, e') cross sections, where the nucleon momentum distributions are derived from self-consistent mean-field calculations. By further introducing the energy and momentum conservation in the scaling analysis, an improved ψ'scaling function is proposed to investigate the high-momentum part of the momentum distributions. Using the proposed scaling function, we systematically explore the effects of the nucleon-nucleon short-range correlation(NN-SRC) on the(e, e') cross sections. From the experimental(e, e') data, the NN-SRC strength is further extracted within the framework of the improved ψ'scaling function. The studies in this paper offer a new method to investigate the nucleon momentum distributions and the NN-SRC effects in nuclei.

关键词： inclusive electron scattering scaling analysis nucleon momentum distribution nucleon-nucleon correlation

Penetration of disk fragments following impact on thin plate

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Journal of Zhejiang University-Science A(Applied physics & Engineering) 2009年第5期10卷 677-684页

作者： Juan-juan LI Hai-jun XUAN Lian-fang LIAO Wei-rong HONG Rong-ren WU insititute of Chemical Machinery Zhejiang University Hangzhou 310027 China Shenyang Aeroengine Research Institute Shenyang 110015 China

To investigate the ballistic resistance and failure pattern of aeroengine casing following the impact of disk fragments, and to determine the optimum case structure, the phenomena of a 1/3rd disk fragment impact on single and double-layered thin plate targets were simulated using nonlinear dynamical analysis software ***. Strain rate effect was introduced in a Johnson-Cook (JC) material model for the disk fragment and the plate. Impact modeling was based on the Arbitrary Lagrange-Eulerian method, and simulated using explicit finite element method (FEM). Simulation results showed that the major failure pattern of the plate is shearing and tensile fracture with large plastic deformation. It was also concluded that the ballistic limit velocity increases with the standoff distance when it is beyond a certain value, and that greater resistance is obtained when the front plate has either a proportionately low or high thickness. The impact resistance of a double-layered plate may exceed that of a single plate if the thicknesses and standoff distance of the two plates are set appropriately.

关键词： Aeroengine Disk burst failure Case containment capability Ballistic limit velocity

Microstructure and ^(29)Si NMR spectrum of Taiping orthoclase

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Chinese Science Bulletin 1996年第22期41卷 1891-1895页

作者：薛纪越周玲棣郭九皋李丽云李齐 Laboratory of Solid State Microstructures Nanjing University Nanjing 210093 China Guangzhou insititute of Geochemistry Chinese Academy of SciedcesGuangzhou 510640China Whhan Institute of physics Chinese Academy of SciencesWuhan 430071China

Based on the study of 29Si,27Al NMR spectra for some orthoclases determined byX-ray powder diffraction method,Zhou et *** that there are three maxima for the29Si NMR spectra of these *** order to explain the three max... 详细信息

关键词： orthoclase microstructure 29Si NMR spectrum Taiping of Anhni.

Influence of reaction temperature on the formation process of ZnO quantum dots and the optical properties

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Optoelectronics Letters 2009年第1期5卷 1-5页

作者：庄晋艳李岚张晓松徐建萍魏军 insititute of Material physics Key Laboratory of Display Materials and Photoelectric DevicesMinistry of EducationTianjin Key Laboratory for Optoelectronic Materials and DevicesTianjin University of Technology insititute of Material physics Key Laboratory of Display Materials and Photoelectric Devices Ministry of EducationTianjin Key Laboratory for Optoelectronic Materials and DevicesTianjin University of Technology Colloge of Information Science Tianjin University of Technology Singapore Institute of Manufacturing Technology

ZnO quantum dots (QDs)with the sizes of 3.0-5.6 nm are synthesized by solution-phase method at different temperatures. We find that temperature has great influence on the size of ZnO QDs. The growth process is the most sensitive to temperature, and the process is well explained by Lifshitz–Slyozov–Wagner (LSW) model. By photoluminescence (PL) spectra of the quantum dots at different temperatures and reactive time, we come to a conclusion that ultraviolet emission is mainly due to surface defects, and the or...

关键词： Electron mobility Emission spectroscopy Optical properties Semiconducting zinc compounds Surface defects Zinc oxide

Further improvement of the Lyapunov functional and the delay-dependent stability criterion for a neural network with a constant delay

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Chinese physics B 2012年第4期21卷 179-184页

作者：邱芳张全信邓学辉 Department of Mathematics and Information Science Binzhou UniversityBinzhou 256603China insititute of Differential Equation and Dynamical System Binzhou UniversityBinzhou 256603China

This paper investigates the asymptotical stability problem of a neural system with a constant delay. A new delay-dependent stability condition is derived by using the novel augmented Lyapunov-Krasovskii function with triple integral terms, and the additional triple integral terms play a key role in the further reduction of conservativeness. Finally, a numerical example is given to demonstrate the effectiveness and lower conservativeness of the proposed method.

关键词： neural system globally asymptotical stability time delay

Realization of adiabatic and diabatic CZ gates in superconducting qubits coupled with a tunable coupler

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Chinese physics B 2021年第4期30卷 81-85页

作者： Huikai Xu Weiyang Liu Zhiyuan Li Jiaxiu Han Jingning Zhang Kehuan Linghu Yongchao Li Mo Chen Zhen Yang Junhua Wang Teng Ma Guangming Xue Yirong Jin Haifeng Yu Beijing Academy of Quantum Information Sciences Beijing 100193China Shenzhen insititute for Quantum Science and Engineering Southern University of Science and TechnologyShenzhen 518055China

High fidelity two-qubit gates are fundamental for scaling up the superconducting qubit *** use two qubits coupled via a frequency-tunable coupler which can adjust the coupling strength,and demonstrate the CZ gate using two different schemes,adiabatic and diabatic *** Clifford based randomized benchmarking(RB) method is used to assess and optimize the CZ gate *** fidelities of adiabatic and diabatic CZ gates are 99.53(8)% and 98.72(2)%,*** also analyze the errors induced by the *** to 30 ns duration time of adiabatic CZ gate,the duration time of diabatic CZ gate is 19 ns,revealing lower incoherence error rate r’_(incoherent),int=0.0197(5) compared to r_(incoherent,int)=0.0223(3).

关键词： controlled-Z gates high fidelity gates tunable coupler

POSITRON ANNIHILATION STUDY ON DEFORMATION OF HIGH PURITY ALUMINIUM AT DIFFERENT STRAIN RATES

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Chinese Science Bulletin 1991年第3期36卷 249-252页

作者：吴奕初王明华常香荣田中卓肖纪美何永枢 Department of Materials physics Beijing University of Science and Technology Beijing 100083 PRC insititute of High Energy physics Academia Sinica Beijing 100080 PRC

Ⅰ. INTRODUCTIONGenerally speaking, when metals are deformed, the S-parameter of positron annihilation increases obviously with the strain increasing. The parameter gradually tends to saturation when the strain is getting larger and larger. Park et al. concluded that the variation of positron lifetime with the strain was dependent on the conditions of deformation (coldrolling, bending and tensile stretching at 200 K). The lifetimes of positron at the edge and

关键词： strain rate positron annihilation S-ε curve.

Structural investigation and luminescent properties of BaZr(BO_3)_2:Eu^(3+) phosphors containing Si

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Chinese Science Bulletin 2010年第29期55卷 3252-3255页

作者： ZHANG ZhongPeng LI GuangMin ZHANG XiaoSong XU ShengYan JI Ting LI Lan insititute of Material physics Tianjin University of Technology Key Laboratory of Display Materials and Photoelectric Devices Ministry of Education Tianjin Key Laboratory for Optoelectronic Materials and Devices Tianjin 300191 China Department of Fundamental Subjects Tianjin Institute of Urban Construction Tianjin 300384 China Tianjin Xinhua Staff and Workers University Tianjin 300040 China

Si4+-doped BaZr(BO3)2:Eu3+ phosphors are prepared by a conventional solid-state *** influence of Si4+ addition on the charge transfer state of Eu3+-O2- and photoluminescence(PL) properties of BaZr(BO3)2:Eu3+ are *** temperature PL spectra indicated that efficient emission is obtained by Si *** values for the peak-peak ratio(PPR) of BaZr(BO3)2:Eu3+ at higher Si doping concentrations implied that the Eu3+ ion is located in a more asymmetric environment in BaZr0.8Si0.2(BO3)2:Eu3+ than in the undoped *** Judd-Ofelt parameters Ωλ(λ=2,4) were calculated from the PL data,giving results that were consistent with those from the *** maximum radiative quantum efficiency was achieved at a Si doping concentration of 20 mol%.

关键词： Si掺杂铕离子荧光粉发光性能结构调查硅掺杂固相反应电荷转移

A Case Study of the Impacts of Dust Aerosols on Surface Atmospheric Variables and Energy Budgets in a Semi-Arid Region of China

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Atmospheric and Oceanic Science Letters 2010年第3期3卷 145-150页

作者： Ling Xiao-Lu Guo Wei-Dong Zhang Lei Zhang Ren-Jian Key Laboratory for Semi-Arid Climate Change of the Ministry of Education College of Atmospheric Sciences Lanzhou University Lanzhou 730000 China Key Laboratory of Regional Climate-Environment for East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China insititute for Climate and Global Change Research University School of Atmospheric Sciences Nanjing University Nanjing 210093 China

The authors present a case study investigating the impacts of dust aerosols on surface atmospheric variables and energy budgets in a semi-arid region of China. Enhanced observational meteorological data, radiative fluxes, near-surface heat fluxes, and concentrations of dust aerosols were collected from Tongyu station, one of the reference sites of the International Coordinated Energy and Water Cycle Observations Project (CEOP), during a typical dust storm event in June 2006. A comprehensive analysis of these data show that in this semi-arid area, higher wind velocities and a continuously reduced air pressure were identified during the dust storm period. Dust storm events are usually associated with low relative humidity weather conditions, which result in low latent heat flux values. Dust aerosols suspended in the air decrease the net radiation, mainly by reducing the direct solar radiation reaching the land surface. This reduction in net radiation results in a decrease in soil temperatures at a depth of 2 cm. The combination of increased air temperature and decreased soil temperature strengthens the energy exchange of the atmosphere-earth system, increasing the surface sensible heat flux. After the dust storm event, the atmosphere was dominated by higher pressures and was relatively wet and cold. Net radiation and latent heat flux show an evident increase, while the surface sensible heat flux shows a clear decrease.

关键词： case study dust aerosol energy budget semiarid region