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NONEQUILIBRIUM STATISTICAL THEORY OF FATIGUE FRACTURE(Ⅰ)——THE MICROSCOPIC MECHANISM AND STATISTICAL NATURE OF FATIGUE CRACK GROWTH

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Science in China,Ser.A 1986年第10期29卷 1051-1062页

作者：邢修三 institute of atomic {2. beijing

In papers (Ⅰ) and (Ⅱ), we try by nonequilibrium statistical concepts and methods to construct a theory of fatigue fracture in connecting mnicroscopic mechanism with macroscopic properties. In this paper the physical picture of fatigue fracture process is described. The stochastic growth equation is given. The dislocation mechanism of growth is discussed. The transport growth rate and fluctuation growth coefficient are obtained, and thus the microcrack distribution function is derived.

关键词： NONEQUILIBRIUM STATISTICAL THEORY OF FATIGUE FRACTURE THE MICROSCOPIC MECHANISM AND STATISTICAL NATURE OF FATIGUE CRACK GROWTH length rate exp

RELATIVISTIC CALCULATION OF IONIZATION ENERGIES FOR TITANIUM IONS Ti Ⅰ TO Ti XXII

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原子与分子物理学报 1998年第1期 4-9页

作者： Chen Bo1,2. Tan Mingliang2.Jiang Gang2.Zhu Zhenghe2.Zhao Yongkuan3( 1 institute of Nuclear Science and Technology, Sichuan Union University, Chengdu 610064, P. R. China.2.institute of {2. and Molecular Physics, Sichuan Union Un

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关键词： Ti ion Ionization energy MCDF technique

Near infrared lights emission of ^(40)Ar^(16+) impacting on metal surfaces

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Science China(Physics,Mechanics & Astronomy) 2009年第7期52卷 1021-1026页

作者： ZHANG XiaoAn1,2. XIAO GuoQing2. YANG ZhiHu2. WANG Li1 & ZHAN WenLong2.1 Department of Physics, Xianyang Normal University, Xianyang 712.00, China 2.institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China Department of Physics Xianyang Normal University Xianyang 712000 China institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China

The highly charged ion 40Ar16+ with the velocity (kinetic energy EK=150 keV, velocity V=8.5×105 m/s) smaller than Bohr velocity (VBohr=2.9×106 m/s) was found to hove impacts on the surfaces of metals Ni, Mo, Au and Al, and the Ar atomic infrared light lines and X-rays spectra were simultaneously measured. The experimental results show that the highly charged ion that captures electrons is neutralized, and the multiply-excited hollow atom forms. The hollow atom cascade decay radiates lights from infrared to X-ray spectrum. The intensity of infrared lights shows that the metallic work functions play an important role in the neutralization process of highly charged ions during their interaction with metallic surfaces, which verifies the classical over-the-barrier model.

关键词： infrared light lines X-ray neutralization highly charged ions

Mechanism of catalytic hydropyrolysis of sedimentary organic matter with MoS_2

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Petroleum Science 2011年第2期8卷 134-142页

作者： He Kun Zhang Shuichang Mi Jingkui Chen Jianping Cheng Lei Petroleum Geology Research and Central Laboratory Research Institute of Petroleum Exploration and Development （RIPED） PetroChina Beijing 100083 China CNPC Key Laboratories for Petroleum Geochemistry Beijing 100083 China

MoS2.was used as an efficient catalyst for hydropyrolysis （Hypy） of three samples of sedimentary organic matter with different maturities. Through comparison with Soxhlet extraction （SE）, it was found that MoS2.catalytic Hypy can remarkably promote the yields of total chloroform extracts, saturates, aromatics, hopanes and steranes. In addition, the difference of biomarker parameters indicated that isomerization of covalently-bound biomarkers is much more difficult than their free counterparts. Meanwhile, the high conversion of total organic carbon （TOC） in MoS2.catalytic Hypy of organic matter proved that the presence of dispersed molybdenum sulfide accelerated the breaking of C-C bonds and the release of hydrocarbons. To address the catalytic mechanism, a series of control experiments based on free Hypy and catalytic Hypy were conducted. The results showed that the calculated atomic ratio of carbon conversion/hydrogen conversion for catalytic Hypy was much larger than the presumed value of 1/2. indicating that intensive hydrogenation took place and significantly influenced the distribution of liquid products. Analysis of stable hydrogen isotope data, infrared spectra and m/z 83 ion chromatograph of the saturate fraction further confirmed this hypothesis. The difference of S content changing （AS） between catalyst-free Hypy and catalytic Hypy, and the thermal characteristics of the catalyst, indicated that active H2. was definitely generated and it probably initiated free radical reactions in the early stage of hydropyrolysis of organic matter.

关键词： Catalytic hydropyrolysis molybdenum disulfide kerogen coal Soxhlet extraction,biomarkers

The Angular Distribution of Light Composite Particle Projectile in Preequilibrium Reactions

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Chinese journal of nuclear physics 1994年第2期16卷 160-169页

作者： Shen Qingbiao(China institute of atomic {2.,P.O.Box 2.5,beijing 102.13) China Inst of atomic energy Beijing China

Formulations of double differential cross sections of light composite particleconsidering (1,m) and (2.m) pickup type reactions simultaneously for semi-classicalmulti-step compound and direct processes are *** calculated results of crosssections,spectra,and double differential cross sections indicate that generally the con-tributions of the (2.m) pickup type reactions are about 15%-2.% when the incident en-ergies are below 50 MeV but can become dominant when the incident energies areabove 50 MeV in some region of the outgoing energies and *** forward tenden-cy of the calculated angular distributions by (2.m) configuration is weaker than those by(1,m) *** the reactions of outgoing composite particle with higher inci-dent energy,the multi-step direct process must be considered.

关键词： Preequilibrium Composite particle Double differential cross section

Study for ^(2.8)Th reduction in thermal reactor with Th-U fuel cycls

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Nuclear Science and Techniques 1999年第1期10卷 48-50页

作者： XU Xiaoqin (China institute of atomic {2., beijing 102.1s) China institute of atomic {2. Beijing 102413 China

By using computer code WIMS/CENDL, the effects of some parameters, core configuration such as fuel element structure, neutron flux and burn-up, are discussed in this paper. It is shown that high neutron flux, small fuel rod diameter, large volume ratio of coolant to fuel, seed-blank heterogeneous core arrangement and 2.1 Pa chemical separation are necessary for reducing 2.8Th production in reactor.

关键词：热反应堆钍-铀 2.8钍减少

Effects of Y2.1 phase contents on the critical current density J_c and microstructural analysis in YBCO bulk superconductors

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Rare Metals 2002年第4期21卷 282-288页

作者： SHA Jianjun, YU Gang, and YU JinnanChina institute of atomic {2., P. O. Box 2.5-51, beijing 102.13, China China institute of atomic {2. P.O. Box 275-51 北京 102413

YBCO bulk superconductors were prepared by the solid state reaction andtop-seed-melt-textured growth (TSMTG) process. By using the AC susceptibility measurement, thecritical transition temperature T_c of samples is 91.5 K for the highest value, and the transitionwidth ΔT_c is less than 1 K. The highest magnetization critical current densities J_c achieved 10~6A/cm^2.under 5 T at 10 K and 1.35X10^4 A/cm^2.under 2.T at 70 K (H//c), respectively. The resultscombining the SEM observation indicate that doping of Y2.1 particles is more effective in improvingthe growth quality of melt-textured YBCO superconductor and in reducing the micro-cracks ofspecimens. Doping of Y_2._3 powder forms the rod-shaped Y2.1 particles, but doping of Y2.1 particlesdirectly to matrix materials forms the spherical Y2.1 particles mainly. Combining themicrostructures with J_c measurements shows that the interfaces are most important on flux bundlepinning, in which the gradient of free energy is larger than that of other place between the Y2.1particles and the Y12. matrix materials.

关键词： quasi-single domain melt-textured Y2.1 particles critical current density magnetic flux pinning

The anharmonic effect study of coupled Morse oscillators for the unimolecular reaction

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Science China Chemistry 2008年第12期51卷 1146-1152页

作者： YAO Li1,2.& LIN Sheng-Hsien2.31 Department of Physics, Dalian Maritime University, Dalian 11602., China 2.institute of atomic and Molecular Sciences, Academia Sinica, Taipei 10764, China 3 Department of Applied Chemistry and institute of Molecular Sciences, Chiao-Tung University, Hsinchu 30051, Taiwan, China 1. Department of Physics Dalian Maritime University Dalian 116026 China 2. institute of atomic and Molecular Sciences Academia Sinica Taipei 10764 China 3. Department of Applied Chemistry and institute of Molecular Sciences Chiao-Tung University Hsinchu 30051 Taiwan China

The importance of anharmonic effect in dissociation of molecular systems especially clusters has been noted. In this paper, we shall study the effect of coupled anharmonic oscillator of the standard bilinear form (SBF) Morse oscillator (MO) potential on unimolecular reaction. We shall use the systematic theoretical approach, YL method, proposed by Yao and Lin (YAO L, et. al. J Phys Chem A, 2.07, 111(2.): 672.-672.), which can evaluate anharmonic effects on the rate constants based on the transition state theory. In treating the anharmonic effect with the Morse oscillator potential on unimolecular reactions under collision-free conditions by using the RRKM (Rice-Ramsperger-Kassel-Marcus) theory, the in-verse Laplace transformation of the partition functions was used to obtain the total amount of state and density of state by using the first-order and the second-order approximations of the saddle-point method. To demonstrate the anharmonic effect of the SBF Morse model, we choose some model systems and a real reaction as examples.

关键词： anharmonic effect standard bilinear form Morse oscillator rate constant RRKM theory

Calculation of triaxial superdeformation in ^(174)Hf

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Science China(Physics,Mechanics & Astronomy) 2007年第5期50卷 553-557页

作者： YU ShaoYing1,2.4, LI XiaoWei2. SHEN CaiWan1,5 & CHEN YongShou3,4 1 School of Science, Huzhou Teachers College, Huzhou 313000, China 2.College of Mathematics, Physics and Information Engineering, Zhejiang Normal University, Jinhua 32.000, China 3 China institute of atomic {2., beijing 102.13, China 4 institute of Theoretical Physics, Chinese Academy of Sciences, beijing 100080, China 5 Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator of Lanzhou, Lanzhou 730000, China 1. School of Science Huzhou Teachers College Huzhou 313000 China 2. College of Mathematics Physics and Information Engineering Zhejiang Normal University Jinhua 321000 China 4. institute of Theoretical Physics Chinese Academy of Sciences Beijing 100080 China 5. Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000 China 3. China institute of atomic {2. Beijing 102413 China

A two-dimensional Total Routhian Surface (TRS) calculation with the fixed hexa- decapole deformation ε4 = 0.03 was carried out for several configurations of 174Hf. Results indicate that the shell corrections have an important contribution to the formation of triaxial superdeformation in 174Hf and some possible configuration assignments are made to the 4 TSD bands experimentally found in 174Hf.

关键词： Total Routhian Surface (TRS), triaxial superdeformation, configuration