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A new circulating two-cell structure for stimulated Brillouin scattering phase conjugation mirrors with 1-J load and 10-Hz repetition rate

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Chinese Optics Letters 2010年第11期8卷 1064-1066页

作者：王雨雷吕志伟郭琦武鹏郑振兴何伟明 National Key Laboratory of Science and Technology on Tunable Laser Harbin Institute of Technology

A new approach to realize high-energy and high-power stimulated Brillouin scattering phase conjugation mirrors （SBS-PCMs） is *** reflectivity of SBS-PCM is investigated under a 10-Hz repetition rate and a high energy *** relationship between reflectivity and input energy is examined experimentally with different PCM structures,focus lengths,and medium cell structures.A medium cell with a circulating structure is designed,and its advantage is demonstrated through an experimental comparison with traditional PCM *** 30-cm focus lens and 150-cm collimation lens are optimized when the input energy reaches 1010 mJ at 10-Hz repetition ***,a reflectivity of 84.7% and a higher energy load using the circulating two-cell structure are achieved.

关键词： Dynamic loads high energy physics Lenses Light polarization Mirrors Optical instruments Optical phase conjugation Reflection Ultrasonics

high energy optically pumped NH_3 terahertz laser with simple cavity

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Chinese Optics Letters 2010年第4期8卷 411-413页

作者：苗亮左都罗纠智先程祖海祁春超吴君竹 Wuhan National Laboratory for Optoelectronics College of Optoelectronic Science and Engineering Huazhong University of Science and Technology

A high energy pulsed terahertz（THz） laser is studied *** laser cavity simply consists of a quartz glass waveguide,a coated GaAs input window,and a crystal quartz output ***3 is filled in the cavity as gain medium,and pumped by an 8-J line-tunable transversely excited atmospheric（TEA） CO_2 *** 9R（16） transition acts as the pump line,55.6-mJ THz radiation（90μm） is obtained at 730-Pa NH_3 *** corresponding conversion efficiency is 13.54%.energy and optimal pressure of amplified spontaneous emission and laser oscillation are compared.

关键词： Conversion efficiency Glass lasers high energy physics Infrared lasers Oxide minerals Pulsed laser applications Pulsed lasers Quartz

high-energy PROTON IRRADIATION EFFECTS ON GaAs/Ge SPACE SOLAR CELLS

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Acta Metallurgica Sinica(English Letters) 2001年第6期14卷 463-466页

作者： R. Wang (The Key Laboratory of Beam Technology and Materials Modification of Ministry of Education, Institute of Low energy Nuclear physics, Beijing Normal University Beijing Radiation Center, Beijing 100875, China) S.D. Yao (Department of Technical Phys The Key Laboratory of Beam Technology and Materials Modification of Ministry of Education Institute of Low Energy Nuclear Physics Beijing Normal University Department of Technical physics Peking University

This paper reports the high-energy proton irradiation effects on GaAs/Ge space solar cells. The solar cells were irradiated by protons with energy of 5-20 MeV at fluence ranging from 1×109 to 7×1013 cm-2, and then their electric parameters were measured at AM0. It was shown that the Isc, Voc and Pmax decrease as the proton energy increasing, and the degradation is relative to proton irradiation-induced defect with a level of Ec-0.41 eV in irradiated GaAs/Ge cells.

关键词： Germanium high energy physics Irradiation Protons Semiconducting gallium arsenide

A new solid-conversion gas detector for high energy X-ray industrial computed tomography

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Optoelectronics Letters 2011年第5期7卷 337-340页

作者：周日峰陈伟民段晓礁 Key Lab. for Optoelectronic Technology & Systems of Ministry of Education Chongqing University

A new type of solid-conversion gas detector is investigated for high energy X-ray industrial computed tomography (HECT). The conversion efficiency is calculated by using the EGSnrc Monte Carlo code on the Linux platform to simulate the transport process of photons and electrons in the detector. The simulation results show that the conversion efficiency could be more than 65%, if the X-ray beam width is less than about 0.2 mm, and a tungsten slab with 0.2 mm thickness and 30 mm length is employed as a radiation conversion medium. Meanwhile the results indicate that this new detector has higher conversion efficiency as well as less volume. Theoretically this new kind of detector could take place of the traditional scintillation detector for HECT.

关键词： Computer operating systems Computerized tomography Conversion efficiency Gas detectors high energy physics Multiphoton processes Tungsten X rays

A Cosmological Model for the Early Universe: The Formation of Fundamental Particles

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Journal of high energy physics, Gravitation and Cosmology 2022年第4期8卷 1073-1083页

作者： Tharwat Mahmoud El-Sherbini physics Department Faculty of Science Cairo University Cairo Egypt

A cosmological model for the very early universe is proposed which may modify the present point of view of physicists and astrophysicists, concerning the very early universe at a miniscule fraction of a second, approximately 10-60 seconds after the Big Bang. The model proposes the presence of a primordial s-particle that, following the Big Bang, was violently ejected in all spatial directions together with extremely high-frequency radiation that dominates this era. The proposed s-particles underwent two geometrical phase transitions in space-time that led to the formation of the known fundamental particles (i.e., dark matter, quarks, electrons, neutrinos, etc.). Furthermore, in the model, the four fundamental forces may be accommodated within one structural framework. It shows that the electronic charge is not a fundamental quantity (intrinsic property of the particle), but rather that it can be derived from the tangential velocity of the s-particle. Moreover, it appears that the masses of the fundamental particles are proportional to the curvature of the path of the s-particle.

关键词： Cosmology Nongalactic Astrophysics Particle physics high energy physics Atomic physics

Chinese Scientists in Dubna(1956–1965)

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Chinese Annals of History of Science and Technology 2021年第2期5卷 31-88页

作者： LIU Jinyan WANG Fang Alexey ZHEMCHUGOV Institute for the History of Natural Sciences Beijing 100190China Dzhelepov Laboratory of Nuclear Problems Joint Institute for Nuclear ResearchDubna 141980Russia

The work of Chinese scientists conducted at the Joint Institute for Nuclear Research(JINR)(1956–1965)was inextricably linked to the Sino-Soviet relations in the 1950 s–1960 *** the early stage of the JINR,with the aid of advanced equipment and the international cooperation mechanism,Chinese scientists yielded significant results,such as the discovery of the antisigma-minus hyperon and the proof of the law of partial conservation of axial current(PCAC).After the Sino-Soviet split,Chinese scientists’activities at the institute were hampered by political tensions,eventually resulting in China’s withdrawal from the JINR in *** through the involvement at the JINR,Chinese scientists were trained in scientific practices and participated in international exchange and cooperation which turned them into a new force in China’s nuclear industry,boosting its nuclear weapons,particle physics theory,and accelerator *** the meantime,the scientists’activities extended the international influence of the *** withdrawal of China from the institute impacted both the JINR and the development of science in China.

关键词： Chinese scientists JINR Dubna high energy physics PCAC antisigmaminus hyperon

从SCOAP3模式看图书馆资源建设的范式转变

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