检索结果-南通市图书馆

HOT DIPPING ALUMINIZED COATING AS HYDROGEN PERMEATION BARRIER

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2001年第6期14卷 435-440页

作者： Z. Y Yao, M. Chini, A. Aiello and G. Benamati (china institute of {2. energy, P.O.Box 2.5-51, beijing 1024.3, china) ( department of physics, University of Trento, 38100 Trento, Italy) ( ENEA CR Brasimone, 40032.Camugnano, Bologna, Italy) china Inst. of atomic {2. P.O. Box 275-51 Beijing 102413 China

The hydrogen permeation experiment of MANET II with hot dipping aluminized coating was performed in temperature range of 573 to 62. K, in gas phase and in liquid Pb-17Li phase. The hydrogen permeation reduction factor (PRF) evaluated in gas phase is 62. at 573 K and 2.0 at 62. K, and in liquid Pb-17Li phase is 2.-45 at 573 K and 12.30 at 62. K. The self-healing of coating is obvious and effective above 673 K. The pressure dependence of permeation flux indicates strong surface contribution. The way of filling hydrogen by continuous flow and/or bubble can increase permeation flux. The result of SEM-EDS shows that the microcrack is on the surface of the wetted part, but not on the not wetted part. The crack is superficial and affects only thin outside layer not penetrate aluminized layer. The surface elemental analysis shows that Al/O atomic ratio changes from 2.3 of not wetted part to about 1 of wetted part. The damage of coating surface seems to be related to the interaction of outside layer with liquid Pb-17Li and thermal stress during heating sample.

关键词： Electroless plating Hydrogen Maraging steel Mechanical permeability

Photodissociation/photoionization processes of chlorobromomethane induced by femtosecond laser pulses with pump-probe scheme

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2008年第5期53卷 681-686页

作者： ZHANG Feng1,2. WEI ZhengRong1,2. CAO ZhenZhou1,2. ZHANG ChangHua1,2.& ZHANG Bing1,2.1 State Key Laboratory of Magnetic Resonance and atomic and Molecular physics, Wuhan {2. of physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, china 2.Graduate University of Chinese Academy of Sciences, beijing 100039, china State Key Laboratory of Magnetic Resonance and atomic and Molecular physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan China Graduate University of Chinese Academy of Sciences Beijing China

The photodissociation/photoionization processes of chlorobromomethane (CH_2.rCl) induced by fem- tosecond laser pulses have been investigated using pump-probe scheme combined with the time-of-flight mass spectra. The dominate photoproducts are observed at different delay time of the pump (400 nm) and probe (800 nm) pulses and the corresponding time-dependence of them is obtained. The results show that the decaying time of the molecule CH_2.rCl in the A-band is in the 100 fs. The decaying tendencies of the fragment ions (CH_2.l^+ and CH_2.r^+) and the parent ion (CH_2.rCl^+) are almost the same and the relative ratios of the yields of them keep constant during the delay time of 0 to 150 fs. These facts suggest that the fragment ions come from the fragmentation of the parent ions in excited electronic states. The probabilities to form CH_2.l^+ and CH_2.r^+ are obtained from the relative ratio of the ion intensity and are about 71.6% and 14.2., respectively.

关键词：毫微秒激光氯溴化甲烷激光探针光解作用光化电离作用

The feature study on the π and proton rapidity distributions at AGS, SPS and RHIC

在线全文

学校读者我要写书评

暂无评论

Science china(physics,Mechanics & Astronomy) 2009年第2期52卷 198-206页

作者： FENG ShengQin1,2.& YUAN XianBao1,3 1 College of Science, china Three Gorges University, Yichang 443002. china 2.School of {2. and Technology, Wuhan University, Wuhan 430072. china 3 institute of Particle {2., Central china Normal University, Wuhan 430070, china College of Science China Three Gorges University Yichang China School of physics and Technology Wuhan University Wuhan China institute of Particle physics Central China Normal University Wuhan China

The features of nuclear stopping power and multi-hadron production systematically are studied by making an analysis of rapidity distributions of pion and proton at AGS, SPS and RHIC in this work. It is found that nuclear stopping power increases linearly with project rapidity yp at AGS and SPS, but that is not liner at RHIC. It is argued that the average rapidity loss is saturated at central rapidity region at RHIC. For pion distribution, it is found that the phase space of pion distribution distributes uniformly in the longitudinal direction,and a linear relationship of L with log s is given at AGS and SPS. Non-uniform flow model may explain the features of the distribution at AGS and SPS, but may not ex- plain those of at RHIC.

关键词： non-uniform flow model average rapidity loss baryon number density nuclear stopping power

THE atomic WEIGHT OF CERIUM

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 1994年第4期5卷 357-360页

作者： Tsing Lien CHANG.(department of Chemistry, Peking University, beijing 100871)Yong Fu LIU({2. institute of nuclear energy, beijing 1024.3)

Isotopic ratio measurement was carried out for cerium on a thermal ionization mass spectrometer, which was calibrated by using a europium standard as substitute, yielding a new value of the atomic weight of cerium as ...

关键词：

A systematic investigation of high harmonic generation using mid-infrared driving laser pulses

在线全文

学校读者我要写书评

暂无评论

Science china(physics,Mechanics & Astronomy) 2010年第6期53卷 1054-1059页

作者： YAO JinPing 1,2.,XIONG Hui 1 ,XU Han 1 ,FU YuXi 1,2.,ZENG Bin 1,2.,CHU Wei 1,2.,CHENG Ya 1 ,XU ZhiZhan 1 ,LIU XiaoJun 3 & CHEN Jing 4,5 1 State Key Laboratory of High Field Laser physics,Shanghai institute of Optics and Fine Mechanics,Chinese Academy of Sciences,Shanghai 2.1800,{2. 2.Graduate University of Chinese Academy of Sciences,beijing 100049,{2. 3 State Key Laboratory of Magnetic Resonance and atomic and Molecular physics,Wuhan institute of physics and Mathematics,Chinese Academy of Sciences,Wuhan 430071,{2. 4 institute of Applied physics and Computational Mathematics,beijing 100088,{2. 5 Center for Applied physics and Technology,Peking University,beijing 100084,{2. State Key Laboratory of High Field Laser physics Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai China Graduate University of Chinese Academy of Sciences Beijing China State Key Laboratory of Magnetic Resonance and atomic and Molecular physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan China institute of Applied physics and Computational Mathematics Beijing China Center for Applied physics and Technology Peking University Beijing China

We report on a systematic investigation of the influences of gas pressure,focal position and focusing geometry on high harmonic generation by use of mid-infrared femtosecond laser pulses. We also discuss the spatial characteristics of harmonics under different focusing conditions. By optimizing the parameters,we experimentally observed the generation of 1 kHz,low divergence coherent X-ray beams in the water-window region.

关键词： mid-infrared laser pulses high harmonic generation water window

Suppression　of　Interference　Speckles　in　the　Uniform　Line　Focus　System　of　Segmented　Wedge　Array　Using　Phase－disturbed　Plate

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Lasers 1996年第4期B5卷 363-370页

作者： LIU Zhongyong ZHENG Ruilun(physics department of South-West Normal University,Chongqing630715,{2.)SUI Zhan(Laboratory for Laser Fusion,institute of nuclear physics and Chemistry ,{2. Academy of Engineering physics,Chendu 610003, china)LU Baida CAI South West Normal Univ Chongqing China

ＳｕｐｐｒｅｓｓｉｏｎｏｆＩｎｔｅｒｆｅｒｅｎｃｅＳｐｅｃｋｌｅｓｉｎｔｈｅＵｎｉｆｏｒｍＬｉｎｅＦｏｃｕｓＳｙｓｔｅｍｏｆＳｅｇｍｅｎｔｅｄＷｅｄｇｅＡｒｒａｙＵｓｉｎｇＰｈａｓｅ－ｄｉｓｔｕｒｂｅｄＰｌａｔｅ￥Ｌ... 详细信息

ＳｕｐｐｒｅｓｓｉｏｎｏｆＩｎｔｅｒｆｅｒｅｎｃｅＳｐｅｃｋｌｅｓｉｎｔｈｅＵｎｉｆｏｒｍＬｉｎｅＦｏｃｕｓＳｙｓｔｅｍｏｆＳｅｇｍｅｎｔｅｄＷｅｄｇｅＡｒｒａｙＵｓｉｎｇＰｈａｓｅ－ｄｉｓｔｕｒｂｅｄＰｌａｔｅ￥ＬＩＵＺｈｏｎｇｙｏｎｇ；ＺＨＥＮＧ...

关键词： phase-disturbed plate phase modulation time smoothing interference

atomic force microscopy studies of SrTiO_(3)(001)substrates treated by chemical etching and annealing in oxygen

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china(physics,Mechanics & Astronomy) 2005年第4期48卷 459-468页

作者： WANG Xu1, FEI Yiyan1, LU Huibin1, JIN Kui-juan1, ZHU Xiangdong1,3, CHEN Zhenghao1, ZHOU Yueliang1 & YANG Guozhen1 1. beijing National Laboratory for Condensed Matter physics,{2. of physics,Chinese Academy of Sciences,beijing 100080,china 2. department of physics,University of California, Davis,California,USA beijing National Laboratory for Condensed Matter physics Institute of Physics Chinese Academy of Sciences Beijing China department of physics University of California Davis USA

The SrTiO3 (001) substrates treated by chemical etching in NH4F-buffered HF solution and annealing in oxygen ambient have been studied by an atomic force microscopy (AFM). The SrTiO3 substrates with TiO2.termineted and atomically smooth surfaces and single unit cell steps have been obtained. The surface morphologies of SrTiO3 substrates strongly depend on the treated conditions and the quality of the substrates.

关键词： SrTiO3, AFM, surface morphology, surface defects.

COMMENT ON WHETHER THE CONTACT TERM CONTRIBUTES TO DOUBLE CHARGE EXCHANGE REACTION

在线全文

学校读者我要写书评

暂无评论

中国科学院研究生院学报 1989年第2期6卷 48-51页

作者： Ma Weihsing (Center of Theoretical physics, CCAST (World Lab.), beijing) Yu Ziqiang ({2. of physics, Nankai University, Tianjin, china) He Hanxin (institute of atomic energy, Academia Sinica)

Based on the Olsson-Turn’s Lagrangian, contribution to DCX reaction from the contact term has been discussed, The result shows that althought there are some cancellations between the pole-and contact-term contributio... 详细信息

关键词： carefully contributions priori invariant Lagrangian 切二 nuclei Proceedings vertex Alamos

Density functional theory study on the structural and electronic properties of Ag-adsorbed (MgO)_n clusters

在线全文

学校读者我要写书评

暂无评论

Science china(physics,Mechanics & Astronomy) 2009年第5期52卷 734-741页

作者： GE GuiXian1, JING Qun1 & LUO YouHua2.3 1 Key Laboratory of Ecophysics and department of physics, Normal College, Shihezi University, Shihezi 832.03, china 2.School of Science, East china University of Science and Technology, Shanghai 2.02.7, china 3 institute for Theoretical physics, Henan University, Kaifeng 475004, china Key Laboratory of Ecophysics and department of physics Normal College Shihezi University Shihezi China School of Science East China University of Science and Technology Shanghai China institute for Theoretical physics Henan University Kaifeng China

Equilibrium geometries, charge distributions, stabilities and electronic properties of the Ag-adsorbed (MgO)n (n = 1-8) clusters have been investigated by density functional theory (DFT) with generalized gradient approximation (GGA) for exchange-correlation functional. The results show that hollow site is energetically preferred for n≥4, and the incoming Ag atoms tend to cluster on the existing Ag cluster. The Mulliken populations indicate that the interaction between the Ag atom and Magnesia clusters is mainly induced by a weak atomic polarization. The adsorbed Ag atom only causes charge redistributions of the atoms near itself. The effect of the adsorbed Ag atom on the bonding natures and structural features of Magnesia clusters is minor. Furthermore, the investigations on the first energy difference, fragmentation energies and electron affinities show that the Ag(MgO)4 and Ag(MgO)6 are the most stable among studied clusters.

关键词： Ag (MgO)_n clusters geometries electronic properties