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240keV DOUBLE-PULSE LIA DEVICE

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240keV DOUBLE-PULSE LIA DEVICE

The 17th International Conference on High-Power Particle Beams

作者： JING Xiaobing~1 Mu Fan~1 Pang Haifeng~1 Zhang Kaizhi~1 Shi Jinshui~1 Deng Jianjun~1 1 :Institute of Fluid physics CAEP P.O.Box 919-106 Mianyang 621900 China Cheng Cheng~2 Liao Shu-qing~2 Lin Yu-zheng~2 Tang Chuan-xiang~2 Zheng Shu-xin~2 2:Accelerator Lab. dept.of engineering physics Tsinghua University Beijing 100084 China

＜正＞A small linear induction electron accelerator has been developed to explore the technology of generate intense electron beams in megahertz burst rate.A train of two 240keV,1.2A electron beams was obtained in the accelerator *** beam has a full width at half maximum of 80ns,with rise time of 30ns,and the duration time between two beams can be adjusted easily but not less than *** paper describes the physics design,development and experimental results of the *** key technology is analyzed.

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来源： cnki会议评论

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物理溅射的Monte Carlo模拟

计算物理 1988年第2期 235-240页

作者：崔福斋李文治李恒德郑里平清华大学工程物理系中国科学院上海原子核研究所

模拟载能离子在固体传输及原子碰撞级联过程的Monte Carlo程序TCIS,已用于考察物理溅射问题。溅射过程中,低能原子碰撞是很重要的。因此,本文详细研究了二体碰撞计算中时间积分τ的数值大小及其对溅射计算的影响。对TCIS模拟溅射物理模... 详细信息

模拟载能离子在固体传输及原子碰撞级联过程的Monte Carlo程序TCIS,已用于考察物理溅射问题。溅射过程中,低能原子碰撞是很重要的。因此,本文详细研究了二体碰撞计算中时间积分τ的数值大小及其对溅射计算的影响。对TCIS模拟溅射物理模型、输入参数作了介绍,并给出某些模拟研究结果。模拟程序可提供溅射的原子水平的信息,这对于开展有关机理的研究是很有用的。

关键词：溅射真空沉积 Monte Carlo 原子碰撞碰撞(物理) 溅射产额物理

A TWO-DIMENSIONAL LAGRANGIAN TECHNIQUE FOR FLOW FIELD MEASUREMENT UNDER HIGH DYNAMIC PRESSURE

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Acta Mechanica Sinica 1990年第2期6卷 188-192页

作者： Huan Shi (dept.of Applied physics Changsha Institute of Technology)Ding Jing (dept.of engineering Mechanics Beijing Institute of Technology) dept. of Applied physics Changsha Institute of Technology Changsha China dept. of engineering Mechanics Beijing Institute of Technology Beijing China

In this paper,a two-dimensional(2-D)Lagrangian technique for flow field measurement under high dynamic pressure is presented,which includes a set of experimental device and 2-D Lagrange composite manganin-constantan ring *** this kind of gage,the histories of pressure and radial displacement can be measured simultaneously at different Lagrange positions in an axisymmetric shock loading flow field. The technique has some advantages over the 1-D one,such as,simplified loading device,continuously adjust- able output pressure,no restriction on sample length and the availability for the study of lateral rarefaction in shock *** a preliminary application,the processes of 2-D shock initiation and attenuation in compacted TNT are measured.

关键词： Lagrange gage 2-D measurement shock initiation high velocity impact

Compressive Sensing Approach in Multicarrier Sparsely Indexing Modulation Systems

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China Communications 2017年第11期14卷 151-166页

作者： Mostafa Salah Osama A.Omer Usama S.Mohamed dept. of Electrical engineering Sohag University Sohag Egypt dept. of Electrical engineering Aswan University Aswan 81542 Egypt dept. of Electrical engineering Assiut University Assiut Egypt dept. of Electronics & Comm. engineering Arab Academy for Science Technology and Maritime Transport Aswan

recently the indexed modulation(IM) technique in conjunction with the multi-carrier modulation gains an increasing attention. It conveys additional information on the subcarrier indices by activating specific subcarriers in the frequency domain besides the conventional amplitude-phase modulation of the activated subcarriers. Orthogonal frequency division multiplexing(OFDM) with IM(OFDM-IM) is deeply compared with the classical OFDM. It leads to an attractive trade-off between the spectral efficiency(SE) and the energy efficiency(EE). In this paper, the concept of the combinatorial modulation is introduced from a new point of view. The sparsity mapping is suggested intentionally to enable the compressive sensing(CS) concept in the data recovery process to provide further performance and EE enhancement without SE loss. Generating artificial data sparsity in the frequency domain along with naturally embedded channel sparsity in the time domain allows joint data recovery and channel estimation in a double sparsity framework. Based on simulation results, the performance of the proposed approach agrees with the predicted CS superiority even under low signal-to-noise ratio without channel coding. Moreover, the proposed sparsely indexed modulation system outperforms the conventional OFDM system and the OFDM-IM system in terms of error performance, peak-to-average power ratio(PAPR) and energy efficiency under the same spectral efficiency.

关键词： indexed modulation combinatorial modulation double sparsity critical sparsity sparsely indexed modulation OFDM-IM

Studies of Atomic Structure and Physical Properties of Metal Clusters in MgO by HREM and Nano-probe Methods

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Journal of Materials Science & Technology 1997年第4期13卷 265-270页

作者： Nobuo Tanaka (dept. of Applied physics, School of engineering, Nagoya University, Nagoya, 464-01, Japan) dept. of Applied physics School of Engineering Nagoya University Nagoya 464-01 Japan

Nanometer-sized metal clusters were prepared inside single crystalline MgO films by vacuum co-deposition of metals and MgO. The atomic structure was studied by high-resolution electron microscopy (HREM) and nm-area electron diffraction. The size of the clusters is ranging from 1 nm to 3 nm without those larger than 5 nm, and most of them have definite epitaxial orientations with the MgO matrix films. The character of the composite films is very much useful for the studies of various kinds of physical properties with anisotroPy. The physical properties such as electric transport, magnetic, optical absorption, sintering and catalytic ones were thus measured on the same samples analyzed by HREM by using high sensitivity apparatus with interest of clarifying the retationship between the atomic structure and physical properties

关键词： Figure Nano Studies of Atomic Structure and Physical Properties of Metal Clusters in MgO by HREM and Nano-probe Methods HREM MgO

ANALYTICAL SOLUTION FOR AXISYMMETRIC PROBLEM OF THICK LAMINATED CLOSED CANTILEVER SHELIS IN HAMILTON SYSTEM

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Acta Mechanica Solida Sinica 1998年第2期11卷 146-158页

作者： Ding Kewei Tang Limin (dept.of engineering Mechanics,Dalian University of Technology,Dalian 116023,China)Fan Jiarang (dept.of Civil engineering,He fei University of Technology,Hefei 230009,China) dept. of engineering Mechanics Dalian University of Technology Dalian 116023 China dept. of Civil engineering Hefei University of Technology Hefei 230009 China

By giving up any assumptions about displacement models and stress distribution,the mixed state Hamilton equation for the axisymmetric problem of the thick laminated closed cantilever cylindrical shells is *** identical analytical solution is obtained for the thin,moderately thick and thick laminated closed cantilever cylindrical *** equations of elasticity can be satis- fied,and all elastic constants can be taken into account.

关键词： Hamilton canonical equation state equation cantilever cylindrical shell exact analysis

Analyses　of　the　Properties　of　Tunable　Faraday　Anomalous　Dispersion　Optical　Filter　at　589nm

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Chinese Journal of Lasers 1995年第1期B4卷 65-71页

作者： PENG Yufeng LI Xuexin(dept.of physics,Henan Normal University,Xinxiang 453002, China)ZHANG Liang TANG Junxiong WANG Qingji(dept.of Rodio-Electronics,Beijing University,Beijing 100871,China) Henan Normal Univ Xinxiang China

ＡｎａｌｙｓｅｓｏｆｔｈｅＰｒｏｐｅｒｔｉｅｓｏｆＴｕｎａｂｌｅＦａｒａｄａｙＡｎｏｍａｌｏｕｓＤｉｓｐｅｒｓｉｏｎＯｐｔｉｃａｌＦｉｌｔｅｒａｔ５８９ｎｍＡｎａｌｙｓｅｓｏｆｔｈｅＰｒｏｐｅｒｔｉｅｓｏｆＴｕｎａｂ... 详细信息

ＡｎａｌｙｓｅｓｏｆｔｈｅＰｒｏｐｅｒｔｉｅｓｏｆＴｕｎａｂｌｅＦａｒａｄａｙＡｎｏｍａｌｏｕｓＤｉｓｐｅｒｓｉｏｎＯｐｔｉｃａｌＦｉｌｔｅｒａｔ５８９ｎｍＡｎａｌｙｓｅｓｏｆｔｈｅＰｒｏｐｅｒｔｉｅｓｏｆＴｕｎａｂｌｅＦａｒａｄａｙＡｎｏｍａｌｏｕ...

关键词： Faraday rotation effect anomalous dispersion atomic resonance filter

EXTRACTION KINETICS,SYNERGISTIC EFFECTS AND INTERFACIAL CHEMISTRY FOR D_2 EHPA MPA-Fe^(3+) MIXED EXTRACTION SYSTEM

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Acta Metallurgica Sinica(English Letters) 1993年第12期6卷 405-410页

作者： YU Jingfen LIU Difei Tsinghua University,Beijing,China professor,dept.of Chemical engineering,Tsinghua University,Beijing 100084,China Tsinghua Univ Beijing China

The thermodynamics of micella formation,interfacial characteristics,synergistic effects and interfacial kinetics for synergistic extraction system D_2 EHPA-MPA-Fe^(3+) have been *** was found that D_2EHPA in the mixed system strongly exhibits the effect on the micella formation thermodynamics and interracial characteristics of *** ther- modynamic parameters for constants of micelles formation(K_m).free energies of micelles formation(ΔG_m)and critical micella concentrations(CMC)were *** inter- facial adsorption behaviour of D_2EHPA is opposite to that of *** emulsification for single MPA and the mixed system was *** synergistic effects were found in this mixed extraction *** is proved that the process of the Fe^(3+) extraction for non-mixed extraction system is controlled by chemical reaction and the controlling reaction occurs at the interface.

关键词： interfacial chemistry synergistic effect Fe^(3+) extraction kinetics

MICROMECHANICAL MODELLING OF STRAIN SOFTENING IN MICROCRACK-WEAKENED QUASI-BRITTLE MATERIALS

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Acta Mechanica Solida Sinica 1995年第2期8卷 121-132页

作者： Feng Xiqiao Yu Shouwen(dept.of engineering Mechanics,Tsinghua University,Beijing 100084,P.R.China) dept. of engineering Mechanics Tsinghua University Beijing 100084 China

By using the concept of domain of microcrack growth(DMG),the micromechanisms of damage in quasi-brittle materials subjected to triaxial either tensile or compressive loading are investigated and the complete strew-strain relation including four stages is obtained from micromechanical *** regime of pre-peak nonlinear hardening corresponds to the distributed damage,*** stable propagation of *** the attainment of the ultimate strength of load-bearing capacity, some microcracks experience the second unstable growth and the distributed damage is transmitted to the localization of *** analyses improve our understanding of the hardening and softening behaviors of quasi-brittle materials.

关键词： microcracks strain softening constitutive relation micromechanical damage mechanics brittle material