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A statistical model for porous structure of rocks

Science china(Technological Sciences) 2008年第11期51卷 2040-2058页

作者： JU Yang1,2, YANG YongMing1, SONG ZhenDuo3 & XU WenJing4.1 State Key Laboratory of Coal Resources and Safe Mining, china university of Mining & technology, Beijing 100083, china 2 {4. of Mechanical and Manufacturing Engineering, The university of Calgary, 2500 university Drive NW Calgary, AB T2N 1N4. Canada 3 china National Coal Mining Equipment Co. Ltd, Beijing 100011, china 4.{4. of Materials and Metallurgy, The university of Utah, Salt Lake City, Utah 84.12, USA State Key Laboratory of Coal Resources and Safe Mining China University of Mining & Technology china National Coal Mining Equipment Co. Ltd department of Materials and Metallurgy The University of Utah

The geometric features and the distribution properties of pores in rocks were in- vestigated by means of CT scanning tests of sandstones. The centroidal coordi- nates of pores, the statistic characterristics of pore distance, quantity, size and their probability density functions were formulated in this paper. The Monte Carlo method and the random number generating algorithm were employed to generate two series of random numbers with the desired statistic characteristics and prob- ability density functions upon which the random distribution of pore position, dis- tance and quantity were determined. A three-dimensional porous structural model of sandstone was constructed based on the FLAC3D program and the information of the pore position and distribution that the series of random numbers defined. On the basis of modelling, the Brazil split tests of rock discs were carried out to ex- amine the stress distribution, the pattern of element failure and the inosculation of failed elements. The simulation indicated that the proposed model was consistent with the realistic porous structure of rock in terms of their statistic properties of pores and geometric similarity. The built-up model disclosed the influence of pores on the stress distribution, failure mode of material elements and the inosculation of failed elements.

关键词： porous structure statistical model random numbers reconstruction rocks

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X-ray spectra induced by ^(129)Xe^(q+) impacting the metal surface

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Science china(Physics,Mechanics & Astronomy) 2008年第1期51卷 82-89页

作者： ZHANG XiaoAn 1,2 ,XIAO GuoQing 1 ,YANG ZhiHu 1 ,CHEN XiMeng 3 ,ZHAO YongTao 1 , LI FuLi 4.,WANG Li 1,2 ,CUI Ying 3 ,ZHANG HongQiang 3 &ZHAN WenLong 1 1Institute of Modern Physics,Chinese Academy of Sciences,Lanzhou 730000,china 2department of Physics,Xianyang Normal university,Xianyang 712000,china 3department of Modern Physics,Lanzhou university,Lanzhou 730000,china 4.1} of Applied Physics,Xi’an Jiaotong university,Xi’an 71004.,china Institute of Modern Physics Chinese Academy of Sciences department of Physics Xianyang Normal University

Using the slow highly charged ions 129 Xe q+ (q=25,26,27;initial kinetic T0≤4.65 keV/a.u.)to impact Au surface,the Au atomic Mαcharacteristic X-ray spectrum is *** result shows that as long as the charge state of projectile is high enough,the heavy atomic characteristic X-ray can be effectively excited even though the incident beam is very weak(nA magnitude),and the X-ray yield per ion is in the order of 10-8and increases with the kinetic energy and potential energy of *** measuring the Au Mα-X-ray spectra,Au atomic N-level lifetime is estimated at about 1.33×10-18s based on Heisenberg uncertainty relation.

关键词： slow highly charged ions characteristic X-ray level lifetime

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Modelling of multi-bodies in close proximity under water waves——Fluid resonance in narrow gaps

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Science china(Physics,Mechanics & Astronomy) 2011年第1期54卷 16-25页

作者： LU Lin1,2,TENG Bin3,CHENG Liang 4.SUN Liang5 & CHEN XiaoBo6 1 Center for Deepwater Engineering,Dalian university of technology,Dalian 116024.china 2 State Key Laboratory of Structural Analysis for Industrial Equipment,Dalian university of technology,Dalian 116024.china 3 State Key Laboratory of Coastal and Offshore Engineering,Dalian university of technology,Dalian 116024.china 4.School of Civil and Resource Engineering,The university of Western Australia,Crawly 6003,Australia 5 Centre for Offshore Research and Engineering,department of Civil Engineering,National university of Singapore,117576,Singapore 6 Research department,Bureau Veritas,Neuilly-Sur-Seine,92570,France Dalian university of technology Center for Deepwater Engineering Dalian China (GRID:grid.30055.33) (ISNI:***) Dalian university of technology State Key Laboratory of Structural Analysis for Industrial Equipment Dalian China (GRID:grid.30055.33) (ISNI:***) Dalian university of technology State Key Laboratory of Coastal and Offshore Engineering Dalian China (GRID:grid.30055.33) (ISNI:***) The university of Western Australia School of Civil and Resource Engineering Crawly Australia (GRID:grid.1012.2) (ISNI:***) National university of Singapore Centre for Offshore Research and Engineering Department of Civil Engineering Singapore Singapore (GRID:grid.4280.e) (ISNI:***) Bureau Veritas Research Department Neuilly-Sur-Seine France (GRID:grid.432925.b)

Viscous fluid model and potential flow model with and without artificial damping force(f=-μV,μ the damping coefficient and V the local averaging flow velocity) are employed in this work to investigate the phenomenon of fluid resonance in narrow gaps between multi-bodies in close proximity under water *** numerical results are compared with experimental data available in the *** comparison demonstrates that both the viscous fluid model and the potential flow model are able to predict the resonant frequency reasonably *** the conventional potential flow model(without artificial damping term) significantly over-predicts the wave height in narrow gaps around the resonant *** order to calibrate the appropriate damping coefficient used for the potential model and make it work as well as the viscous fluid model in predicting the resonant wave height in narrow gaps but with little computational efforts,the dependence of damping coefficient μ on the body geometric dimensions is examined considering the parameters of gap width Bg,body draft D,body breadth ratio Br and body number n(n = 2,3),where Br = BB/BA for the case of two bodies(Body A and Body B) with different breadths of BA and BB,*** was confirmed that the damping coefficient used for the potential flow model is not sensitive to the geometric dimensions and spatial *** was found that μ∈ [0.4.0.5] may guarantee the variation of Hg/H0 with kh to be generally in good agreement with the experimental data and the results of viscous fluid model,where Hg is the excited wave height in narrow gaps under various dimensionless incident wave frequencies kh,H0 is the incident wave height,k = 2π/L is the wave number and h is the water depth.

关键词： narrow gap fluid resonance water wave viscous fluid model potential flow model finite element method boundary element method

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The onset and advance of the Asian summer monsoon

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Science Bulletin 2006年第1期51卷 80-88页

作者： Lü Junmei1,2,4. ZHANG Qingyun1, TAO Shiyan1 & JU Jianhua3 1. State Key Laboratory of Numerical Modeling for Atmospheric Sci- ences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, china 2. department of Atmospheric Sciences, Yunnan university, Kunming 650091, china 3. china Meteorological Administration Training Centre, Beijing 100081, china 4. Graduate School of Chinese Academy of Sciences, Beijing 100039, china State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China department of Atmospheric Sciences Yunnan University Kunming 650091 China Graduate School of Chinese Academy of Sciences Beijing 100039 China china Meteorological Administration Training Centre Beijing 100081 China

Based on the daily outgoing longwave radiation (OLR) data from National Oceanic and At- mospheric Administration (NOAA) satellites, the Cli- mate Prediction Center’s merged analysis of pre- cipitation (CMAP) data and the National Centers for Environmental Prediction/National Center for At- mospheric Research (NCEP/NCAR) reanalysis dataset, the mean intraseasonal variability of the Asian summer monsoon (ASM) is investigated by using power spectrum analysis, band-pass filter, and diagnostic analyses. The processes of the onset and advance of monsoon over the southern part of Indo- china Peninsula, the east coast of Bay of Bengal, the South china Sea and the Indian subcontinent are explored. It is found that there is an abrupt change in OLR, precipitation and zonal wind during the onset and advance of the ASM. It is also indicated that the southern part of Indochina Peninsula and the adja- cent Andaman Sea is the region where the earliest onset of the ASM occurs in the 2nd pentad of May.

关键词： Asian summer monsoon intraseasonal variability onset advance.

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Electroluminescence and photoluminescence of dioctylfluorene and 4.7-dithien-2-yl-2,1,3-benzothiadiazole copolymers

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Chinese Science Bulletin 2002年第20期47卷 1714-1717页

作者： PENG Junbiao, XU Yishe, HOU Qiong, NIU Yuhua, RUAN Wenying & CAO YongInstitute of Polymer Optoelectronic Materials & Devices, South china university of technology, Guangzhou 51064., china {4. of Applied Physics, South china university of technology Inst. of Polymer Optoelectron. Mat. South China University of Technology Guangzhou 510640 China department of Applied Physics South China University of Technology Guangzhou 510640 China

Dioctylfluorene (DOF) and 4.7-dithien-2-yl-2,1,3-benzothiadiazole (DBT) copolymers synthesized in our lab with different compositions of DBT (1%, 5%, 15% and 25%) were utilized to fabricate bilayered light emitting diodes. External quantum efficiency (QE) of the diode fabricated from the copolymer with 15% DBT content reaches 1.4. (ph/el), over 1.0 cd/A in luminance efficiency at the driving voltage of 4.2 V. The highest luminance can reach 3780 cd/m2 at 8.2 V. Devices emit a saturated red light centered at 675 nm with chromaticity coordinate changed from x=0.66, y=0.32 for PDOF-DBT1 (1% DBT) to x=0.70, y= 0.28 for PDOF-DBT25 (25% DBT).

关键词： dioctylfluorene and 4 7-dithien-2-yl-2 l 3-benzothiadia-zole copolymer polymer light emitting diode saturated red emission.

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Synthesis of superheavy nuclei with ^(238)U target

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Science china(Physics,Mechanics & Astronomy) 2009年第10期52卷 1482-1488页

作者： LIU ZuHua1,3 & BAO JingDong2,4.1 Key Laboratory of Beam technology and Material Modification of Ministry of Education,Beijing Normal university,Beijing 100875,china 2 department of Physics,Beijing Normal university,Beijing 100875,china 3 china Institute of Atomic Energy,Beijing 1024.3,china 4.Center of Theoretical Nuclear Physics,National Laboratory of Heavy Ion Accelerator of Lanzhou,Lanzhou 730000,china Key Laboratory of Beam technology and Material Modification of Ministry of Education Beijing Normal University Beijing China china Institute of Atomic Energy Beijing China department of Physics Beijing Normal University Beijing China Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou China

The production of superheavy nuclei with Z=108-116 via hot fusion reactions of the neutron-rich projectiles with 238U target is systematically *** results show that the production cross sections of superheavy nuclei do not decrease monotonously as the atomic number Z *** cross sections of the superheavy nuclei at Z = 112 and 115 are enhanced as compared with the whole Z-trend in synthesis of the superheavy nuclei,which clearly illustrates that the reactions with large negative Q-value and shell correction are more favorable to synthesize superheavy nuclei.

关键词： superheavy nuclei fusion reaction cross section 238U target

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Advanced information feedback strategy in intelligent two-route traffic flow systems

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Science china(Information Sciences) 2010年第11期53卷 2265-2271页

作者： DONG ChuanFei1,2, MA Xu1,3 & WANG BingHong1,4.1department of Modern Physics and Nonlinear Science Center, university of Science and technology of china (USTC), Hefei 230026, china 2School of Earth and Atmospheric Sciences, Georgia Institute of technology, Atlanta, GA 30332, USA 3 department of Physics, Syracuse university, Syracuse, NY 1324., USA 4.he Research Center for Complex System Science, university of Shanghai for Science and technology and Shanghai Academy of System Science, Shanghai 200093, china department of Modern Physics and Nonlinear Science Center University of Science and Technology of China (USTC) School of Earth and Atmospheric Sciences Georgia Institute of Technology department of Physics Syracuse University The Research Center for

The optimal information feedback has a significant effect on many socioeconomic systems like stock market and traffic systems aiming to make full use of resources. In this paper, we study dynamics of traffic flow with real-time information. The influence of a feedback strategy named vehicle number feedback strategy (VNFS) is introduced, in which we only calculate the vehicle number of first 500 route sites from the entrance. Moreover, the two-route traffic system has only one entrance and one exit, which is different from those in the previous work. Our model incorporates the effects of adaptability into the cellular automaton models of traffic flow, and simulation results by adopting this optimal information feedback strategy have demonstrated higher efficiency in controlling spatial distribution of traffic patterns than the other three information feedback strategies, i.e., TTFS, MVFS and CCFS.

关键词： vehicle number feedback strategy two-route selecting traffic flow intelligent vehicle cellular automaton model

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Orthogonally linear polarized lasers (I)——principle and devices

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Progress in Natural Science:Materials International 2005年第7期15卷 586-595页

作者： ZHANG Shulian and XU Ting (State Key Laboratory of Precision Measurement technology and Instruments, department of Precision Instruments, Tsinghua university, Beijing 100084. china) State Key Laboratory of Precision Measurement technology and Instruments Department of Precision Instruments Tsinghua University Beijing 100084 China

Two kinds of orthogonally polarized lasers, i. e. Zeeman dual-frequency lasers and four-frequency ring lasers (laser gyros) have been developed since the invention of lasers, in which circularly polarized lights oscillate. This paper summarizes recent progress of the study on orthogonally linear polarized lasers with the standing wave cavity. Firstly, the expression of producing orthogonally linear polarized lights in standing wave cavity, i. e. laser frequency splitting, is given. Almost all the birefringence effects made in laser cavity are used to produce orthogonally linear polarized lights. The effect includes quartz crystal birefringence effect, calcite birefringence effect, stress (photo-elastic) birefringence effect and electro-optical birefringence effect. Secondly, several physical phenomena of orthogonally linear polarized lasers are discovered such as aberrance of frequency splitting curves caused by optical activity of quartz crystal, order-passing of longitudinal modes with frequency splitting and strong modes competition. Finally, because the traditional Zeeman dual frequency laser cannot output frequency difference larger than 3 MHz, the approaches of obtaining larger frequency difference are studied. The sequential results, several kinds of orthogonally polarized lasers, are described, such as birefringence dual frequency lasers outputting a frequency difference from 4. MHz to hundreds of megahertz, birefringence-Zeeman dual frequency lasers outputting a frequency difference from 1 MHz to hundreds of megahertz, the LD pumped YAG birefringence dual frequency laser outputting frequency difference of several gigahertz, and the lasers whose longitudinal mode spacing is c/4. instead of c/2L .

关键词： orthogonally polarized laser dual frequency laser intra-cavity birefringence Zeeman effect photo-elastic birefringence electro-optical birefringence frequency splitting.

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Construction and application of formal ontology for mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 577-582页

作者： CHENG Gang 1, 2, ZHANG Yin-ling1, 2, WANG Fei 1 ,2, ZHANG Zhen-hui 3, GUO Yu-xiang1, 2 1. Key Laboratory of Mine Spatial Information Technologies of State Bureau of surveying and mapping, Henan Polytechnic university, Jiaozuo 4.4.03, china 2. School of surveying and land Information Engineering, Henan Polytechnic university, Jiaozuo 4.4.03, china 3. Qingdao Branch of Naval Aeronautical Engineering Institute, Qingdao 26604., china Key Laboratory of Mine Spatial Information Technologies of State Bureau of surveying and mapping Henan Polytechnic University Jiaozuo 454003 China School of surveying and land Information Engineering Henan Polytechnic University Jiaozuo 454003 China Qingdao Branch of Naval Aeronautical Engineering Institute Qingdao 266041 China

Digital mine is the only way for the development of mining industry in china. Due to lack of appropriate standards and norms, and different awareness in the field of digital mine among academia and industry insiders, the meaning for digital mine is still unclear. Starting from the nature of mining and removing of views of specialized fields, this paper constructs formal ontology for digital mine and proposes the four levels for it. The ontology clarifies the concept world for digital mine, defines the meaning of concepts and relations clearly, provides a reference for the standard construction for digital mine and provides a unified semantic framework for the integration of heterogeneous mine data. Meanwhile, it can provide formal reasoning knowledge for expert system of digital mine and improve the intelligence and automation while the machine automatically interpreting and processing mine spatial data.

关键词： Digital mine formalization ontology concept world semantic share

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Rearrangement of Hydrolysis Products of Tetrahydrofolate model compound

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Chinese Chemical Letters 1999年第9期10卷 727-728页

作者： Jian Xin CHENI Jun Sheng HAO Wei GUO Chi Zhong XIA(1Datong Medical College,Datong,Shanxi 0370082department of Chemistry. Shanxi university, taiyuan 030006) Datong Medical College department of Chemistry Shanxi University

The hydrolysis products of tetrahydrofolate model compound 4.were a mixture of 6 and 7 and the rearrangement reaction between 6 and 7 via 5 was in a state of equilibrium, confirmed by (HNMR)-H-1 and IR spectra.

关键词： tetrahydrofolate hydrolysis rearrangement

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