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NONEQUILIBRIUM STATISTICAL THEORY OF FATIGUE FRACTURE (Ⅱ)——FROM MICROSCOPIC MECHANISM TO MACROSCOPIC PROPERTIES OF FATIGUE FRACTURE

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中国科学A辑(英文版) 1986年第12期29卷 1318-1333页

作者：邢修三 institute of atomic energy Beijing

The stochastic evolution equation of microcracks is given. The microcrack density distribution function is obtained on the basis of dislocation mechanism. The fatigue fracture probability, reliability, σ_a-N curves,... 详细信息

关键词： fatigue deviation stochastic Probability dislocation quantities latter brittle hardening infinite

Inconsistency between WMAP data and released map

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Chinese Science Bulletin 2010年第10期55卷 907-909页

作者： LIU Hao1 & LI TiPei1,2,3.1 Key Laboratory of Particle Astrophysics,institute of High energy Physics,Chinese Academy of Sciences,Beijing 100049,china 2 Department of Physics & Center for Astrophysics,Tsinghua University,Beijing 100084,china 3.Department of Engineering Physics & Center for Astrophysics,Tsinghua University,Beijing 100084,china Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China Department of Physics & Center for Astrophysics Tsinghua University Beijing China Department of Engineering Physics & Center for Astrophysics Tsinghua University Beijing China

A remarkable inconsistency between the calibrated differential time-ordered data (TOD) of the Wilkinson Microwave Anisotropy Probe (WMAP) mission,which is the input for map-making,and the cosmic microwave background (CMB) temperature maps published by the WMAP team is revealed,indicating that there must exist a serious problem in the map making routine of the WMAP *** inconsistency is easy to be confirmed without the use of WMAP map-making *** view of the importance of this issue for cosmology study,we invite readers to check it by themselves.

关键词：威尔金森微波各向异性探测器 WMAP 地图制作宇宙微波背景有序数据制作软件 TOD CMB

Electronic structure and magnetism of Fe-doped SiC nanotubes

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Science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 1582-1589页

作者： ZHANG WeiHu1,2,3.ZHANG FuChun3.ZHANG ZhiYong4,LU ShuYuan5 & YANG YanNing3.1 Xi’an institute of Optics and Precision Mechanics,Chinese Academy of Sciences,Xi’an 710068,china 2 Graduate University of Chinese Academy of Sciences,Beijing 100049,china 3.College of Physics and Electronic Information,Yan’an University,Yan’an 716000,china 4 Information Science and Technology Institution,Northwest University,Xi’an 710127,china 5 Department of Telecommunications,Xi’an institute of Posts and Telecommunications,Xi’an 710121,china 1. Xi’an institute of Optics and Precision Mechanics Chinese Academy of Sciences Xi’an 710068 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. College of Physics and Electronic Information Yan’an University Yan’an 716000 China4. Information Science and Technology Institution Northwest University Xi’an 710127 China5. Department of Telecommunications Xi’an Institute of Posts and Telecommunications Xi’an 710121 China

The electronic structure and magnetic properties of Fe-doped SiC nanotubes are investigated by using the first-principles method based on density functional theory(DFT) in the local spin density approximation(LSDA).The calculation results indicate that the SiC nanotube of Fe substitution for C exhibits antiferromagnetism while ferromagnetism features prominently when Fe substitutes *** is a kind of half-metal magnetic *** formation energy calculation results show that the formation energy of ferromagnetic structure is 3.2 eV lower than that of antiferromagnetic *** atoms are more likely to replace Si ***-orbit coupling induces electron spin polarization in the ground ***,the doping Fe atoms make relaxation towards the outside of the tube to some extent and larger geometric distortion occurs when Fe substitutes C,but the whole geometric structure of SiC nanotubes is not damaged due to the *** is revealed in the calculation of energy band structure and density of states that more dispersed distribution of energy levels is produced near the Fermi *** Fe substitution for Si,obviously there are spin-split and intense p-d hybrid effects by Si 3. electron spins and Fe 3. electron spins localized at the exchanging interactions between magnetic transitional metal(TM) *** electronic density results indicate that system magnetic moments are mainly generated by the unpaired 3. electrons of Fe *** these results show that the transition metal doping SiC nanotube could be a potential route to fabricating the promising magnetic materials.

关键词： SiC nanotube the first-principles doped magnetic properties

Isomerization of B_6,B_6^- and B_6^+ clusters

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Science china Chemistry 2010年第1期53卷 202-209页

作者： WEI GongMin1,PU ZhiFeng2,ZOU Rong3.LI GuoLiang2,3.& LUO Qiong2,3.1Department of Physics,Capital Normal University,Beijing 100048,china 2State Key Laboratory of Explosion Science and Technology Beijing institute of Technology,Beijing 100081,china 3.enter for Computational Quantum Chemistry,South china Normal University,Guangzhou 51063.,china 1. Department of Physics Capital Normal University Beijing 100048 China2. State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology Beijing 100081 China3. Center for Computational Quantum Chemistry South China Normal University Guangzhou 510631 China

The interconversions between isomers with the same spin multiplicity of neutral B6 and charged B6-and B6+ clusters have been investigated at the B3.YP/6-3.1+G level of theory,including determination of the minimum energy pathways with transition states connecting the corresponding reactants and *** dynamic calculations,26 isomers were optimized,including 11 novel *** order to further refine the energies,single-point B3.YP/6-3.1+G(3.f) calculations were carried out on the corresponding B3.YP/6-3.1+G geometries of all isomers of B6,B6-and B6+ and the corresponding isomerization transition *** stability of each isomer of B6(singlet and triplet states),B6-(doublet state) and B6+(doublet state) was analyzed from both thermodynamic and dynamic viewpoints.

关键词： B6 transition state intrinsic reaction coordinate barrier height

energy Transfer among Chlorophylls in Trimeric Light-harvesting Complex Ⅱ of Bryopsis corticulans

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Acta Biochimica et Biophysica Sinica 2006年第5期38卷 310-317页

作者： Su-Juan ZHANG~(1,2*)Shui-Cai WANG~2 Jun-Fang HE~2 Hui CHEN~3. 1 institute of Photonics and Photo-Technology,Northwest University,Xi'an 710069,china 2 State Key Laboratory of Transient Optics and Photonics,Xi 'an institute of Optics and Precision Mechanics,Chinese Academy of Sciences,Xi'an 710068.china 3.Laboratoty of Photosynthesis Basic Research,institute of Botany,Chinese Academy of Sciences,Beijing 100093.china institute of Photonics and Photo-Technology Northwest UniversityXi'an 710069 China State Key Laboratory of Transient Optics and Photonics Xi'an Institute of Optics and Precision Mechanics Chinese Academy of SciencesXi'an 710068 China Laboratory of Photosynthesis Basic Research Institute of Botany Chinese Academy of SciencesBeijing 100093 China

A study on energy transfer among chlorophylls（Chls）in the trimeric unit of the major light-harvesting complex Ⅱ（LHC Ⅱ）from Bryopsis corriculan,was carried out using time-correlated singlephoton *** the chlorophyll Q region of LHC Ⅱ,six molecules characterized as Chlb628,Chlb646,Chlb652654,657,Chla664666,Chla674677.680and Chla682683.ere discriminated according to their absorption spectrumand fluorescence emission ***,excited by pulsed light of 628 nm,fluorescence kinetics spectrain the chlorophyll Q region were *** accordance with the principles of fluorescence kinetics,thesekinetics data were analyzed with a multi-exponential *** constants on energy transfer were *** overwhelming percentage of energy transfer among chlorophylls undergoes a process longer than 97picoseconds（ps）,which shows that,before transferring energy to another Chl,the excited Chl might convertenergy to vibrations of a lower state with different multiplicity（intersystem crossing）.energy transfer at thelevel of approximately 10 ps was also obtained,which was interpreted as the excited Chls may go throughinternal conversion before transferring energy to another *** with a higher standard deviation,timeconstants at the femtosecond level can not be entirely excluded,which can be attributed to the ultrafastprocess of direct energy *** to the arrangement and direction of the dipole moment of Chls inLHC Ⅱ,the probability of these processes is *** fluorescence lifetimes of Chlb652654,657,Chla664666,Chla674677.680and Chla682683.ere determined to be 1.44ns,1.43.ns,63. ps and 713.ps,*** of energy dissipation in the pathway of fluorescence emission were no more than 40% in thetrimeric unit of LHC Ⅱ.These results are important for a better understanding of the relationship between thestructure and function of LHC Ⅱ.

关键词： energy transfer LHC Ⅱ transient spectrum fluorescence kinetics

Decay Data Evaluation for Radionuclide ~7Be

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中国核科技报告 1997年第S2期 68-71页

作者： Zhou Chunmei Huang Xiaolong (china institute of atomic {3., CIAE)

~7Be is a radionuclide of εdecay. It can be useful as standard source of gamma-ray detector calibration. Therefore, its half-live and gamma-ray emission probability need to be known with good accuracy. The decay data were evaluated in 1988. It is important for us to update them. The cutoff date of references retrieved from Nuclear Science References File (NSRF) is November, 1996.

关键词： Be Decay Data Evaluation for Radionuclide

Analysis for twinning and slip in face-centered cubic crystals under axisymmetric co-deformation

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Science china(Technological Sciences) 2006年第5期49卷 521-536页

作者： CHEN Zhiyong1,2, CAI Hongnian1, ZHANG Xinming2, WANG Fuchi1 & TAN Chengwen1,3.1. School of Material Science and Engineering, Beijing institute of Technology, Beijing 100081, china 2. School of Material Science and Engineering, Central South University, Changsha 410083. china 3. School of Material Science and Engineering, Beijing University of Aeronautics and Astronautics, Beijing 100083. china 1. School of Material Science and Engineering Beijing Institute of Technology Beijing 100081 China 2. School of Material Science and Engineering Central South University Changsha 410083 China 3. School of Material Science and Engineering Beijing University of Aeronautics and Astronautics Beijing 100083 China

The maximum work principle of Bishop-Hill was developed to analyze the axisymmetric co-deformation in face-centered cubic crystals (f.c.c.) for twinning on {111} 112 and slip on {111} 110 systems. The influence of ξ , the ratio of critical re- solved shear stress for twinning to slip, on the yield stress states and corresponding active slip or/and twinning systems for orientations in the standard stereographic triangle of cubic crystal was investigated systematically. The Taylor factors and the anisotropy of yield strength for three important orientations [100], [110] and [111] in orientation space were analyzed. It is found that the yield strength asymmetry for the case of axisymmetric de- formation of tension and compression can be explained based on the microscopic theory of crystal plasticity. The concept of orientation factor for twinning ability was proposed and the deformation mechanism map in the orientation space was established for the case of axisymmetric deformation. The deformation texture formation and development of f.c.c. crystals with low stacking fault energy for axisymmetric tension can be explained qualita- tively on the basis of analyzed results.

关键词： twinning slip face-centered cubic crystals axisymmetric co-deformation Bishop-Hill maximum work principle yield strength anisotropy

Prediction method for October 2003.solar storm

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Science china(Technological Sciences) 2006年第5期49卷 629-640页

作者： XIE Yanqiong1, 2, 3. WEI Fengsi1, FENG Xueshang1 & ZHONG Dingkun1, 2 1. State Key Laboratory of Space Weather, Center for Space Science and Applied Research, Chinese Academy of Sciences, Beijing 100080, china 2. Graduate School, Chinese Academy of Sciences, Beijing 10003., china 3. institute of Meteorology, PLA University of Science and Technology, Nanjing 211101, china State Key Laboratory of Space Weather Center for Space Science Applied Research Chinese Academy of Sciences Beijing 100080 China Graduate School Chinese Academy of Sciences Beijing 100039 China institute of Meteorology PLA University of Science Technology Nanjing 211101 China

Aiming at two intense shock events on October 28 and 29, 2003. this paper presents a two-step method, which combines synoptic analysis of space weather ——“observing” and quantitative prediction ——“palpating”, and then uses it to test predictions. In the first step of “observing”, on the basis of observations of the solar source surface magnetic field, interplanetary scintillation (IPS) and ACE spacecraft, we find that the propagation of the shocks is asymmetric relative to the normal direction of their solar sources, and the Earth is located near the direction of the fastest speed and the greatest energy of the shocks. As the two fast ejection shock events, the fast explosion of coronal mass of the extremely high temperature, the strong magnetic field, and the high speed background solar wind are also helpful to their rapid propagation. In the second step of “palpating”, we adopt a new membership function of the fast shock events for the ISF method. The predicted results show that for the onset time of the geomagnetic disturbance, the relative errors between the observational and the predicted results are 1.8% and 6.7%; and for the magnetic disturbance magnitude, the relative errors are 4.1% and 3.1%, re- spectively. Furthermore, the comparison among the predicted results of our two-step method with those of five other prevailing methods shows that the two-step method is advantageous. The results tell us that understanding the physical features of shock propagation thoroughly is of great importance in improving the prediction precision.

关键词： solar storm, interplanetary shock, interplanetary scintillation, two-step method, ISF method.

Molecular dynamics simulations on the structures and properties of ε-CL-20-based PBXs ——Primary theoretical studies on HEDM formulation design

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Science china Chemistry 2007年第6期50卷 737-745页

作者： XU XiaoJuan1,2, XIAO JiJun1, HUANG Hui3. LI JinShan3.& XIAO HeMing1 1 Department of Chemistry, Nanjing University of Science and Technology, Nanjing 210094, china 2 Department of Chemistry, Yancheng Teacher’s College, Yancheng 224002, china 3.institute of Chemical Materials, china Academy of Engineering Physics, Mianyang 621900, china Department of Chemistry Nanjing University of Science and TechnologyNanjing 210094China Department of Chemistry Yancheng Teacher''s CollegeYancheng 224002China institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621900

Five polymer bonded explosives(PBXs)with the base explosive epsilon-CL-20(hexanitrohexaazaisowurtzi-tane),the most important high energy density compound(HEDC),and five polymer binders(Estane 5703.GAP,HTPB,PEG,and F_(23.4))were *** dynamics(MD)method was employed to investigate their binding energies(E_(bind))energy density material(HEDM).According to the calculated binding energies,the ordering of compatibility and stability of the five PBXs was predicted as epsilon-CL-20/PEG 3.≈ epsilon-CL-20/GAP 3.4).By pair correlation function g(r)analyses,hydrogen bonds and vdw are found to be the main interactions between the two *** elasticity and isotropy of PBXs based epsilon-CL-20 can be obviously improved more than pure epsilon-CL-20 *** is not by changing the molecular structures of epsilon-CL-20 for each binder to affect the *** safety and energetic properties of these PBXs are mainly influenced by the thermal capability(C_p^(deg))and density(p)of binders,respectively.

关键词： high energy density material (HEDM), hexanitrohexaazaisowurtzitane (CL-20), polymer bonded explosives (PBXs), molecular dynamics (MD), compatibility, safety properties, mechanical properties, energetic properties