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Exotic structure of the third excited state in^(2.)Na

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Chinese Science Bulletin 2005年第23期50卷 2677-2680页

作者： LI Xihan1,2.3. LIANG Yujie1,2.3. DENG Fuguo1,2.3. LIU Zuhua1,4 & ZHOU Hongyu1,2.3.1. Key Laboratory of Beam Technology and Material Modification of Minister of Education, beijing Normal University, beijing 100875,{2. 2. institute of Low Energy Nuclear Physics, and Department of Material Science and Engineering, beijing Normal University, beijing 100875,{2. 3. beijing Radiation Center, beijing 100875,{2. 4.{2. institute of Atomic Energy,{12.,{2. Key Laboratory of Beam Technology and Material Modification of Minister of Education Beijing Normal University Beijing 100875 China institute of Low Energy Nuclear Physics Department of Material Science and Engineering Beijing Normal University Beijing 100875 China beijing Radiation Center Beijing 100875 China china institute of Atomic Energy Beijing 102413 China

The probability of the last proton being out of the binding potential, P and the root-mean-square (rms) ra- dius (1/2. of the third excited state in 2.Na are calcu- lated by means of asymptotic normalization coefficie... 详细信息

The probability of the last proton being out of the binding potential, P and the root-mean-square (rms) ra- dius (2.1/2. of the third excited state in 2.Na are calcu- lated by means of asymptotic normalization coefficient (ANC) method with the experimental date existing. The results are P=54.73. and 2.1/2.5.2. fm respectively. The P value and the contribution of the asymptotic part to the 2.1/2.are compared with those of several other low energy states in 2.Na. It is found that the valence particle in the third excited state has an obvious larger P than those of other states. The density distribution of the valence proton in this state is also compared with the nucleons in the nuclear core 2.Ne, and a far extended tail can be seen clearly. These results show that the third ex- cited state in 2.Na is a proton halo state.

关键词：钠第三激发态外部结构有效半径密度分布渐近标准化系数

Electronic structure and magnetism of R(Fe,Si)_(12. (R=Y,Nd)

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Science china(Physics,Mechanics & Astronomy) 2006年第2期49卷 195-202页

作者： SUN Guang’ai1, CheN Bo1, DU Honglin2. FAN Zhijian1, GAO Tao3.& QI Xinhua3.. institute of Nuclear Physics and Chemistry, china Academy of Engineering Physics, Mianyang 62.900, china 2. Department of physics, Peking university, beijing 100871, china 3. institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, china institute of Nuclear Physics and Chemistry China Academy of Engineering Physics Mianyang China Department of physics Peking university Beijing China institute of Atomic and Molecular Physics Sichuan University Chengdu China

The newly developed full-potential linearized augmented plane wave (LAPW) and local orbitals (lo) based on standard APW methods are briefly introduced, and the structure and magnetic properties of R(Fe, Si)12.compounds (R = Y, Nd) are calculated using the method. The distribution of Si at different sites is analyzed based on total energy of one crystal unit with structure having been optimized. The characters of magnetic mo-ments, total density of states (TDOS) and partial density of states (PDOS) for different crystal sites Si occupies are obtained and analyzed. The results show that the total mag-netic moments of RFe10Si2.(R = Y, Nd) are larger than those of RFe10M2.(M = Ti, V, Cr, Mn, Mo and W) and the hybridization mechanism is seen as follows. Si(8j) reduce the mag-netic moments of Fe at three sites, however, Si(8f) mainly reduce the magnetic moments of Fe(8i) and Fe(8j) atoms. The Curie temperature is markedly enhanced by the introduc-tion of Si atoms according to spin fluctuation of DOS at Fermi level.

关键词： (L)APW+lo method R(Fe Si)12.R = Y Nd) magnetic moment Density of state.

A mixed method for measuring low-frequency acoustic properties of macromolecular materials

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Science china(Physics,Mechanics & Astronomy) 2006年第6期49卷 729-739页

作者： LIU Hongwei1,YAO Lei1,3.ZHAO Hong1,3.ZHANG Jichuan2.3.& XUE Zhaohong2.1. National Key Laboratory of Acoustics,institute of Acoustics,Chinese Academy of Sciences,{3. 100080,{2. 2. institute of Chemistry,Chinese Academy of Sciences,{3. 100080,{2. 3. Graduate University of Chinese Academy of Sciences,{3. 100049,{2. National Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Beijing China Graduate University of Chinese Academy of Sciences Beijing China institute of Chemistry Chinese Academy of Sciences Beijing China

A mixed method for measuring low-frequency acoustic properties of macro-molecular materials is presented. The dynamic mechanical parameters of materials are first measured by using Dynamic Mechanical Thermal Apparatus(DMTA) at low frequen-cies,usually less than 100 Hz; then based on the Principles of Time-Temperature Super-position (TTS),these parameters are extended to the frequency range that acousticians are concerned about,usually from hundreds to thousands of hertz; finally the extended dynamic mechanical parameters are transformed into acoustic parameters with the help of acoustic measurement and inverse analysis. To test the feasibility and accuracy,we measure a kind of rubber sample in DMTA and acquire the basic acoustic parameters of the sample by using this method. While applying the basic parameters to calculating characteristics of the sample in acoustic pipe,a reasonable agreement of sound absorp-tion coefficients is obtained between the calculations and measurements in the acoustic pipe.

关键词： low-frequency acoustic properties,dynamic mechanical properties,Principles of Time-Temperature Superposition,acoustic pipe,sound absorption coefficient.

Characteristics and origins of primary fluids and noble gases in mantle-derived minerals from the Yishu area,Shandong Province,china

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Science china Earth Sciences 2006年第1期49卷 77-87页

作者： MA Jinlong1,2. TAO Mingxin2.3.& YE Xianren2.1. Resources and Environmental School, Lanzhou University, Lanzhou 73.000,{3. 2. Key Laboratory of Gas Geochemistry, {2. of Geology and Geophysics, Chinese Academy of Sciences, Lanzhou 73.000,{3. 3. College of Resources Science & Technology, beijing Normal University, beijing 100875,{3. Resources and Environmental School Lanzhou University Lanzhou China Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou China College of Resources Science & Technology Beijing Normal University Beijing China

Fluids and noble gases of mantle-derived materials are important tracers forthe mantle information. Compositions of primary fluids and noble gases in mantle-derived mineralsfrom the Yishu area, Shandong Province,{2., were tested by the methods of heat-bursting andheat-melting respectively. The fluids are mainly composed of CO_2. CO and H_2. which account forabout 90% of the total, and are similar to the mantle-derived rocks from other areas of easternchina; ratios of ~3.0}/~4he in almost all samples range from 0.82.Ra to 2.74 Ra, whereas^(40)Ar/^(3.)Ar from 2.9.5 to 758.8. Both ranges are much lower than those of the typical oceanmantle-derived samples (such as MORB) and primarily reflect the influences of the atmosphericcomponents and the radiogenic isotopes. Ratios of C/~3.0} range from 2..6 x 10~9 to 1050 x 10~9,N_2.Ar from 92. to 56612. and N_2.~3.0} from 2.5 x 10~9 to 2. x 10~9, similar to those in westernUnited States and New Zealand which belong to the tectonic plate collision regions. The ratios fallin the intersect of mantle-crust-atmosphere in the comprehensive tracer-charts, reflecting theinfluences of the atmosphere and the crusts with organic components. Our results suggest that thecomposition of the primary fluids and the isotopic ratios of the noble gases may either reflect theevolution process of mantle-derived rocks connected with the rise and eruption of magma, or theinfluence of the ancient subduction-plate on the continental mantle of this region.

关键词： noble gases, primary fluids, mantle-derived minerals, Yishu area.

Two possible mechanisms for vortex self-organization

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Science china Earth Sciences 2006年第2期49卷 202-211页

作者： LUO Zhexian2. ZHOU Xiuji1 & GAO Shouting3.1. Chinese Academy of Meteorological Sciences, beijing 100081,{2. 2. Department of Space Information Science, Nanjing University of Information Science and Technology, Nanjing 2.0044,{2. 3. institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 10002.,{2. Department of Environmental Science Nanjing University of Information Science and Technology Nanjing China Chinese Academy of Meteorological Sciences Beijing China institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

The vortex self-organization is investigated in this paper by four groups of numerical experiments within the framework of quasi-geostrophic model, and based on the experimental results two types of possible mechanisms for vortex self-organization are suggested. The meso-scale to-pography may enable separated vortices to merge into a larger scale vortex; and the interaction of meso-γ and meso-β scale systems may make separated vortices to self organize a typhoon-like vor-tex circulation.

关键词： vortex, self-organization, meso-scale topography, interaction of different scales.

Two conceptual models of displacement transfer and examples

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Science china Earth Sciences 2005年第7期48卷 900-911页

作者： GUAN Shuwei1,2. WANG Xin2. YANG Shufeng2. {3. Dengfa1 & ZHAO Weidong3.1. Research institute of Petroleum Exploration and Development, {2. 100083. china 2. Department of Geosciences, Z{3.jiang University, Hangzhou 3.002., china 3. Tarim Oilfield Company, Korla 841000, china Research institute of Petroleum Exploration and Development Beijing 100083 China Department of Geosciences Zhejiang University Hangzhou 310027 China Tarim Oilfield Company Korla 841000 China

This paper presents two conceptual models of displacement transfer, reverse sym- metry model and infinitely equal division model, based on the fault-bend folding theory. If the fault shape is held constant in the trend, then the distribution of slip magnitude, geometry of imbricate structures and its axial surface map all display reverse symmetry on the process of displacement transfer, as called reverse symmetry model in this paper. However, if the ramp height of thrust fault decreases gradually along its strike, the displacement is postulated to be equally and infinitely divided to every thrust that is formed subsequently, this kinematic process is described using infinitely equal division model. In both models, displacement transfer is characterized by the regular changes of imbricate thrusting in the trend. Geometric analysis indicates that the displacement transfer grads can be estimated using the tangent of deflective angle of hinterland structures. Displacement transfer is often responsible for the distortion and branching of the surface anticlines, especially in the region where the multi-level detachment structures is developed. We also present some examples from the frontal structures of the Southern Tianshan fold-and-thrust belt, Xinjiang,{23.. Displacement transfer between deep imbricate thrusts in the middle segment of Qiulitag anticline zone causes the Kuqatawu and Southern Qiulitag deep an- ticlines left-lateral echelon. The region, where these two deep anticlines overlap, is characterized by duplex structures, and extends about 18 km. The shallow anticline is migrated southward displaying obvious “S” form in this area.

关键词： displacement transfer fault-bend folding reverse symmetry model infinitely equal division model Qiulitag zone.

A formal model of fair exchange protocols

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Science in china(Series F) 2005年第4期48卷 499-512页

作者： QING Sihan1,2.3.& LI Gaicheng1,2.3.1. Engineering Research Center for Information Security Technology, {3. of Software, Chinese Aca- demy of Sciences, {2. 100080, china 2. {2. Zhongke Ansheng Corporation of Information Technology, {2. 100080, china 3. Graduate School of the Chinese Academy of Sciences, {2. 10003., china Engineering Research Center for Information Security Technology Institute of Software Chinese Academy of Sciences Beijing China beijing Zhongke Ansheng Corporation of Information Technology Beijing China Graduate School of the Chinese Academy of Sciences Beijing China

Based on the study of existing fair exchange protocols, this paper sets up an accurate formal model by stepwise refinement. In the process of refinement an unreliable channel is employed to simulate an attack behavior. The model provides a novel formal definition of exchanged items, and presents the formal goals for fairness, accountability, etc., reflecting the inherent requirements for fair exchange protocols across-the-board. In order to check, prove, and design fair exchange protocols effectively and efficiently, the model puts forward a novel property of abuse-freeness which applies to all fair exchange protocols, gives a formal definition for trust strand of the third party, and presents general criteria of designing a secure and effective fair exchange protocol. Taking a typical fair exchange protocol as an example, this paper presents the analysis steps of fair exchange protocols appealing to our model. An unknown attack is uncovered. The analysis reveals the process of a complete attack, discovering deeper reasons for causing an attack. Finally, we modify the flawed protocol and the revised protocol ensures the desirable properties.

关键词： events local causal relation local temporal relation global relation exchanged item security goals.

A three-dimensional variational ocean data assimilation system:Scheme and preliminary results

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Science china Earth Sciences 2006年第11期49卷 1212-1222页

作者： ZHU Jiang1,2. ZHOU Guangqing1, YAN Changxiang1, FU Weiwei1 & YOU Xiaobao1,3.1. International Center for Climate and Environment Sciences, institute of Atmospheric Physics, Chinese Academy of Sciences, {2. 10002., china 2. Jiangsu Key Laboratory of Meteorological Disaster, Nanjing University of Information Science and Technology, Nanjing 2.0044, china 3. {2. institute of Applied Meteorology, {2. 10002., china International Center for Climate and Environment Sciences Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Jiangsu Key Laboratory of Meteorological Disaster Nanjing University of Information Science and Technology Nanjing China beijing institute of Applied Meteorology Beijing China

A new 3.VAR-based Ocean Variational Analysis System (OVALS) is developed. OVALS is capable of assimilating in situ sea water temperature and salinity observations and satellite altimetry data. As a component of OVALS, a new variational scheme is proposed to assimilate the sea surface height data. This scheme considers both the vertical correlation of background errors and the nonlinear temperature-salinity relationship which is derived from the generalization of the linear balance constraints to the nonlinear in the 3.VAR. By this scheme, the model temperature and salinity fields are directly adjusted from the altimetry data. Additionally, OVALS can assimilate the temperature and salinity profiles from the ARGO floats which have been implemented in recent years and some temperature and salinity data such as from expendable bathythermograph, moored ocean buoys, etc. A 2.-year assimilation experiment is carried out by using OVALS and the Tropical Pacific circulation model. The results show that the assimilation system may effectively improve the estimations of temperature and salinity by assimilating all kinds of observations. Moreover, the root mean square errors of temperature and salinity in the upper depth less than 42. m reach 0.63. and 0.3. psu.

关键词： data assimilation, 3.VAR, sea surface height, ARGO floats.

Geophysical survey on the tectonic and sediment distribution of Qinghai Lake basin

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Science china Earth Sciences 2006年第8期49卷 851-861页

作者： AN Zhisheng1, WANG Ping2. SheN Ji3. ZHANG Yixiang2. ZHANG Peizhen4, WANG Sumin3. LI Xiaoqiang1, SUN Qianli1, SONG Yougui1, AI Li1, ZHANG Yechun2. JIANG Shaoren2. LIU Xingqi3.& WANG Yong3.. institute of Earth Environment, Chinese Academy of Sciences (CAS), Xi’an 710075, china 2. South china Sea institute of Oceanology, CAS, Guangzhou 5103.1, china 3. Nanjing institute of Geography and Limnology, CAS, Nanjing 2.0008, china 4. institute of Geology, china Earthquake Administration, {12. 10002., china institute of Earth Environment Chinese Academy of Sciences (CAS) Xi’an China South china Sea institute of Oceanology CAS Guangzhou China Nanjing institute of Geography and Limnology CAS Nanjing China institute of Geology China Earthquake Administration Beijing China

The intensive geophysical survey of Qinghai Lake reveals the buried depth of lake sediments and their distribution features. The result indicates that there are three important inter- phases of Qinghai Lake sediments: T1 is the rife interphase of the lake, above which sediments are spread all over the lake basin with roughly the same thickness; T5 is the interphase from which the neotectonic sedimentary cycle begins, and its above sedimentary environment is relatively stable; Tg is the base of the lake basin. Five west-northwest (WNW) fault belts defined the tectonic structure of Qinghai Lake basin: the central hunch around Haixin Shan with two subbasins both in its north and south. The thickness of the lake sediments varies at different places, the thickest sediments are found within the two subbasins. According to the depth that the Sparker System can reach, sediment in the northern subbasin is deeper than 560 m, while sediment in the southern subbasin is deeper than 700 m. The correlation between the seismic sequence stratigraph and the lithology of onshore core shows that Qinghai Lake sediments consist of muddy silt, clay silt, silty clay, gravel silty clay, etc.

关键词： sediment, geophysical survey, Qinghai Lake.