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Local Structure and Dynamics Procedure of Impurities Fe,Al and Mn in Melt Beryllium

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稀有金属材料与工程 2024年第11期53卷 3046-3052页

作者： Zhang Jiqiang Jin Lei Luo Jiangshan Luo Bingchi Wu Weidong research Center of Laser fusion China Academy of Engineering PhysicsMianyang 621900China

The local structure and dynamics of impurities Fe,Al and Mn in beryllium were investigated on an atomic scale using ab initio molecular dynamics and statistical physics *** analysis of the radial distribution function centered on impurity atoms shows that the density of beryllium atoms around Fe and Mn is 8.4%and 8.6%higher than that around Al,*** statistics of the measure square displacement of impurity atoms show that the diffusion coefficients of Al atoms are 114%and 133%larger than that of Fe and Mn atoms in the melt beryllium,*** analysis of velocity autocorrelation function of impurity atom shows that Fe and Mn atoms collide strongly with beryllium atoms in the first coordination layer,indicating that they are tightly surrounded and bound by the surrounding beryllium atoms in the central position,while the beryllium atoms around Al are loosely arranged and have weak binding forces with *** analysis of the activity coefficients of the impurities shows that when Fe or Mn enters the melt beryllium,it reduces the free energy of the system,whereas when Al enters,it increases the system *** summary,the interatomic force of BeAl is weak,so they do not form intermetallic compounds,and Al diffuses quickly in *** BeFe and BeMn have strong interatomic forces,and tend to form more BeFe and BeMn bonds to reduce the free energy of the system,so Fe and Mn diffuse slowly in *** initio molecular dynamics can be used to forecast the best experimental temperature for the vacuum distillation of beryllium.

关键词： beryllium purification ab initio molecular dynamics local structure activity coefficients

Bacterial and archaeal community structures in the Arctic deepsea sediment

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维普期刊数据库

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Acta Oceanologica Sinica 2015年第2期34卷 93-113页

作者： LI Yan LIU Qun LI Chaolun DONG Yi ZHANG Wenyan ZHANG Wuchang XIAO Tian Key Laboratory of Marine Ecology and Environmental Sciences Institute of Oceanology Chinese Academy of Sciences Center for transport Phenomena Energy Research Institute Shandong Academy of Sciences State Field research Station of Jiaozhou Bay Marine Ecology Institute of Oceanology Chinese Academy of Sciences

Microbial community structures in the Arctic deep-sea sedimentary ecosystem are determined by organic matter input, energy availability, and other environmental factors. However, global warming and earlier ice-cover melting are affecting the microbial diversity. To characterize the Arctic deep-sea sediment microbial diversity and its relationship with environmental factors, we applied Roche 454 sequencing of 16 S r DNA amplicons from Arctic deep-sea sediment sample. Both bacterial and archaeal communities＇ richness, compositions and structures as well as taxonomic and phylogenetic affiliations of identified clades were characterized. Phylotypes relating to sulfur reduction and chemoorganotrophic lifestyle are major groups in the bacterial groups; while the archaeal community is dominated by phylotypes most closely related to the ammonia-oxidizing Thaumarchaeota（96.66%） and methanogenic Euryarchaeota（3.21%）. This study describes the microbial diversity in the Arctic deep marine sediment（〉3 500 m） near the North Pole and would lay foundation for future functional analysis on microbial metabolic processes and pathways predictions in similar environments.

关键词： Arctic deep-sea sediment microbial community structure pyrosequencing

Contribution of the Large Helical Device Plasmas to Alfvén Eigenmode Physics in Toroidal Plasmas

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Plasma Science and Technology 2009年第4期11卷 377-380页

作者： K. TOI M. ISOBE M. OSAKABE F. WATANABE K. OGAWA T. TOKUZAWA A. SHIMIZU T. IDO K. IDA, T. ITO S. MORITA K. NAGAOKA K. NARIHARA M. NISHIURA S. OHDACHI S. SAKAKIBARA K. TANAKA LHD Experiment Group National institute for fusion Science Toki 509-5292 Japan Department of energy Engineering and Science Nagoya University Nagoya 464-8601 Japan

In the large helical device （LHD） having three dimensional configuration, Alfven eigenmodes （AEs） destabilized by energetic ions are widely investigated using neutral beam heated plasmas with monotonic and non-monotonic rotational transform （l/2π） profiles. In a plasma with monotonic l/2π-profile, core-localized toroidicity-induced Alfven eigenmode （TAE） as well as global one are often observed. With the increase in the averaged toroidal beta value, defined as the ratio of total plasma pressure to toroidal magnetic pressure, core-localized TAE with low toroidal mode number becomes global. In a relatively high beta plasma with monotonic l/2π-profile, two TAEs with different toroidal mode number often interact nonlinearly and generate another modes through three wave coupling. In a plasma with non-monotonic l/2π-profile generated by intense counter neutral beam current drive, reversed shear Alfven eigenmode （RSAE） and geodesic acoustic mode （CAM） excited by energetic ions were observed for the first time in a helical plasma. Nonlinear coupling was also observed between RSAE and GAM.

关键词： alpha particles Alfven eigenmodes geodesic acoustic mode helical/stellarator

Test of a High Throughput Detector on the X-ray Crystal Spectrometer of the EAST

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Plasma Science and Technology 2013年第2期15卷 97-100页

作者：吕波石跃江王福地万宝年 Manfred BITTER Kenneth W. HILL Sang-gon LEE 李颖颖符佳张继宗徐经翠沈永才 institute of Plasma Physics Chinese Academy of Sciences WCI Center for fusion Theory National Fusion Research InstituteDaejeon 305-806 Korea University of Science and Technology of China Princeton Plasma Physics Laboratory MS37-B332 Princeton New Jersey 08543 USA National fusion research institute 52 Eoeun-Dong Yusung-Gu Taejeon 305-333 Korea

An attempt was made to improve the spatio-temporal resolution of the tangen- tial X-ray crystal spectrometer （XCS） on the Experimental Advanced Superconducting Tokamak （EAST） by evaluating experimentally the applicability of a novel X-ray photon detection tech- nology for measuring the satellite spectra of Ar XVII with a high counting rate. High-resolution experimental data on the profiles of ion temperature and plasma rotation velocity facilitate the studies of the mechanisms underlining important physical phenomena, such as plasma heating, L-H transition and momentum transport. Based on silicon diode array and single-photon counting technology, a relatively small area （83.8 x 33.5 mm~） two-dimensional detector was successfully in- stalled and tested in the recent EAST campaign. X-ray photon counting rate higher than 20 MHz was observed for the first time, and high quality satellite spectra were recorded for ion temperature and plasma rotation measurement, indicating that the new technology is suitable for the next-step high-resolution XCS on EAST, and the deployment of a detector array with a much larger X-ray sensing area is planned for better plasma coverage.

关键词： X-ray crystal spectrometer high resolution ion temperature plasma rotation

Analysis on EAST LHCD Operation Space by Using Simple Core-SOL-Divertor Model

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Plasma Science and Technology 2009年第4期11卷 389-393页

作者： R.HIWATARI A.HATAYAMA S.ZHU Y.TOMITA Central research institute of Electric Power Industry Faculty of Science and Technology Keio University institute of Plasma Physics Chinese Academy of Sciences National institute for fusion Science

A simple core-SOL-divertor model （CSD model） was developed to investigate qual- itatively the overall features of the operational space for the integrated core and edge plasma. In the CSD model, the core plasma model of ITER physics guidelines and the two-point SOL-divertor model are applied, This CSD model is validated by the two dimensional divertor transport code （B2-EIRINE） and by the JT-60U divertor recycling database, and this model is applicable to the low- and high-recycling state of the divertor plasma. The CSD model is applied to the study of the EAST operational space with lower hybrid current drive under various kinds of trade-off for the basic plasma parameters, and the relationship between the operational space and the plasma discharge duration is also discussed.

关键词： core transport SOL-divertor transport operation space EAST LHCD

A Full Aperture Backscattering Light Diagnostic System Installed on the Shenguang-III Prototype Laser Facility

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Plasma Science and Technology 2014年第6期16卷 567-570页

作者：徐涛梅雨魏惠月彭晓世王峰杨冬刘慎业闫亚东 research Center of Laser fusion China Academy of Engineering Physics Xi’an institute of Optics and Precision Mechanics Chinese Academy of Sciences

A full aperture backscattering light diagnostic system （FABLDS） implemented on the Shen Guang-Ⅲ Prototype Laser Facility is described in the paper. FABLDS measures both stimulated brillouin scattering （SBS） and stimulated Raman scattering （SRS） with a series of optical detectors. energy sensors record the integrated energy, and streak cameras coupled with spectrometers measure the temporal spectrum of the backscattering light. This paper provides an overview of the FABLDS and detailed descriptions of the optical path. Special components, including off-axis parabolic mirror, spatial filter and optical light filters, are incorporated along the beam path for purifying the scattering light. Several hohlraum targets were employed, including C5H12 gas-filled targets and empty targets in the experiments. Results presented in the paper indicate that the fraction of backscatter light has been obviously shrinked when the laser is smoothed by continuous phase plates （CPP）.

关键词： backscattering light ICF off-axis parabolic mirror hohlraum targets CPP

Preliminary experiment of the Thomson scattering X-ray source at Tsinghua University

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Chinese Physics C 2008年第1期32卷 75-79页

作者：杜应超黄文会华剑飞何小中程诚杜泰斌唐传祥林郁正袁晓东张保汉张小民魏晓峰张开智刘承俊邓建军 Accelerator Laboratory Department of Engineering and Physics Tsinghua University research Center of Laser fusion CEAP institute of Fluid Physics CEAP

The X-ray source based on Thomson scattering of ultrashort laser pulse with a relativistic electron beam is a means of generating a tunable, narrow bandwidth and ultrashort pulse of hard X-rays. Such a sub-picosecond hard X-ray source is proposed at Tsinghua University, and a preliminary experiment with a 16 MeV Backward Traveling electron linac and a 1.5 J, 6 ns Q-switched Nd：YAG laser is carried out first. A 6 ns pulse X-ray with a peak energy of 4.6 keV and an intensity of *** 104 per pulse is generated successfully in the experiment. The experimental setup, result and discussion are reported in this paper.

关键词： Thomson scattering X-ray laser

Review of condition monitoring and fault diagnosis for marine power systems

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transportation Safety and Environment 2021年第2期3卷 85-102页

作者： Xiaojian Xu Xinping Yan Kun Yang Jiangbin Zhao Chenxing Sheng Chengqing Yuan China Waterborne transport research institute 100088 BeijingChina Reability Engineering institute School of Energy and Power EngineeringWuhan University of TechnologyWuhan430063 HubeiChina National Engineering research Center for Water transport Safety Wuhan University of TechnologyWuhan430063 HubeiChina

The use of condition monitoring and fault diagnosis(CMFD)in marine power systems significantly influences ship *** study divides the development of CMFD for marine power systems into three periods and reviews the content,state and limitations of CMFD research for each *** to the research achievements and engineering experience of the authors’team,typical application cases are introduced for CMFD in ships,including CMFD platforms on engineering ships,salvage ships,container ships and ro-ro ships powered by solar photovoltaic ***,prospective research directions are proposed for CMFD in marine power systems,considering the research status of CMFD and the trend toward intelligent and eco-friendly ships.

关键词： marine power system condition monitoring fault diagnosis new energy ships

energy loss of tens keV charged particles traveling in the hot dense carbon plasma

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Science China(Physics,Mechanics & Astronomy) 2016年第8期59卷 65-72页

作者： ZhenGuo Fu ZhiGang Wang Bin He DaFang Li Ping Zhang Center for fusion energy Science and Technology Chinese Academy of Engineering Physics Beijing 100088 China institute of Applied Physics and Computational Mathematics Beijing 100088 China

The energy loss of charged particles, including electrons, protons, and α-particles with tens keV initial energy E0, traveling in the hot dense carbon(C) plasma for densities from 2.281 to 22.81 g/cm3 and temperatures from 400 to 1500 eV is systematically and quantitatively studied by using the dimensional continuation method. The behaviors of different charged particles are readily distinguishable from each other. Firstly, because an ion is thousands times heavier than an electron, the penetration distance of the electron is much longer than that of proton and α-particle traveling in the plasma. Secondly, most energy of electron projectile with E0 energy transfers into the ion species of C plasma. A simple decreasing law of the penetration distance as a function of the plasma density is fitted, and different behaviors of each projectile particle can be clearly found from the fitted *** believe that with the advanced progress of the present experimental technology, the findings shown here could be confirmed in ion-stopping experiments in the near future.

关键词： stopping power BPS model inertial confinement fusion dense plasmas