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Surface Morphology of Soil Cracks in Yuanmou Dry-hot Valley region,Southwest china

Journal of Mountain Science 2009年第4期6卷 373-379页

作者： XIONG Donghong LONG Yi YAN Dongchun LU Xiaoning JI Zhonghua FANG Haidong Key laboratory of Mountain Hazards and Surface process CAS Chengdu 610041 Sichuan China Institute of Mountain Hazards and Environment CAS Chengdu 610041 Sichuan China Dep.r.ment of Environmental Engineering Chengdu University of Information Technology Chengdu 610225 Sichuan China Institute for Tropical Eco-Agricultural Sciences Yunnan Academy of Agriculture Sciences Yuanmou 651300 Yunnan China

Surface morphology of soil cracks is one of the imp.r.ant factors influencing the water evap.r.tion rate in cracked soil in Yuanmou Dry-hot Valley region,Southwest china. Quantitative study of the complicated surface morphology of soil cracks is a prerequisite for further studies of soil-cracking mechanisms. The present pap.r.establishes a quantitative indicator system by application of concepts and methods originating from Fractal Geometry and Network Analysis. These indicators can effectively express the complicated features of soil-crack network structure. Furthermore,a series of values related to soil-crack morphology was obtained by image processing on field photos of soil-crack quads,and gradation criteria for the degree of development of soil cracks were determined. Finally,the changes in values of the morphological indicators under different degrees of development were analyzed in detail. Our results indicate that (1) the degree of development of soil cracks can be divided into five grades,i.e.,feeble development,slight development,medium development,intensive development and extremely intensive development; (2) the values of the indicators change predictably with increasing degree of development of soil cracks. The area density (Dc) increases,and both the area-weighted mean ratio of crack area to p.r.meter (AWMArp),which reflects the intensity of cracking,and the index r,which is related to the connectivity of a soil crack,grow uniformly (albeit with different forms). AWMrAp increases at a geometric rate while r shows logarithm-mic growth,indicating a gradual increase in theconnectivity of a soil crack. Nevertheless,the area-weighted mean of soil-crack fractal dimension (AWMFrAC) shows a decreasing trend,indicating a gradual decline in the complexity of cracks as area density increases.

关键词： Soil crack Surface morphology Quantitative indicator Degree of development Southwest china

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Emergency assessment of seismic landslide susceptibility: a case study of the 2008 Wenchuan earthquake affected area

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Earthquake Engineering and Engineering Vibration 2009年第2期8卷 207-217页

作者： Tang Chuan,Zhu Jing and Liang Jingtao State Key laboratory of Geo-Hazard prevention,chengdu University of Technology,chengdu 610059,china professor Associate professor Graduate Student State Key laboratory of Geo-Hazard prevention Chengdu University of Technology Chengdu 610059 China

The 8.0 Mw Wenchuan earthquake triggered widespread and large scale landslides in mountainous regions. An ap.r.ach was used to map and assess landslide susceptibility in a given area. A numerical rating system was applied to five factors that contribute to slope instability. Factors such as lithology, topography, streams and faults have an imp.r.ant influence as event-controlling factors for landslide susceptibility assessment. A final map is provided to show areas of low, medium, and high landslide susceptibility. Areas identified as having high landslide susceptibility were located in the central, northeastern, and far south regions of the study area. The assessment results will help decision makers to select safe sites for emergency placement of refuges and plan for future reconstruction. The maps may also be used as a basis for landslide risk management in the study area.

关键词： landslide susceptibility GIS Wenchuan earthquake Qingchuan area

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Kinetic characteristics of continuous flow polymerase chain reaction chip: A numerical investigation

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Science china(Technological Sciences) 2010年第7期53卷 1967-1972页

作者： WANG ShiYing1 & WANG Wei2,3 1 School of physics, peking University, Beijing 100871, china 2 Institute of Microelectronics, peking University, Beijing 100871, china 3.national Key laboratory of Science and Technology on Micro/Nano Fabrication, Beijing 100871, china 1. School of physics Peking University Beijing 100871 China2. Institute of Microelectronics Peking University Beijing 100871 China3. National Key Laboratory of Science and Technology on Micro/Nano Fabrication Beijing 100871 China

Continuous flow p.r.(polymerase chain reaction) chip holds impressive advantages comp.r.d to micro chamber p.r.chip. In order to have better understanding of kinetic characteristics of continuous flow p.r.chip, a comprehensive mathematical model is presented in this pap.r. including melting, annealing and extension phases of a typical p.r.process which has the essence of a convection-diffusion-reaction system. Using this model, we can simulate the p.r.process in series of reaction cycles. Numerical results show that the average sample velocity plays a significant role in affecting the amplification efficiency. Also, ap.r.priate combination of the p.r.mixture is imp.r.ant for high-quality DNA amplification. Giving a large initial DNA concentration range, the continuous flow p.r.scheme holds excellent real-time detection ability theoretically. The present numerical model bridges the temp.r.ture distribution to the real DNA amplification, and thereby is able to successfully predict continuous flow p.r.prop.r.ies which are imp.r.ant for the chip design.

关键词： continuous flow pCr chip numerical simulation convection-diffusion-reaction system

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The migration fractionation: an imp.r.ant mechanism in the formation of condensate and waxy oil

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Chinese Science Bulletin 2000年第14期45卷 1341-1344页

作者： ZHANG ShuichangKey laboratory for petroleum Geochemistry, china national petroleum Corp.r.tion, Beijing 100083, china Key laboratory for petroleum Geochemistry China National Petroleum Corporation Beijing China

Fault-initiated pressure release within reservoirs and the injection of external excessive dry gas may result in occurrence of oil and gas phases. Because of different p.r.itioning coefficients of compounds in two phase flow, lower-molecular-weight components are easier to dissolve in gas phase, yielding condensates, while higher-molecular-weight components are retained in the oil phase, yielding waxy oil cumulations. The fractionation process causes extensive compositional variability in aliphatic/aromatic hydrocarbon ratios, molecular compound distributions and carbon isotope ratios that are traditionally considered to be related to the source organic matter or the thermal maturity.

关键词： migration fractionation condensate waxy oil Lunnan oil zone.

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Fusion tracking in color and infrared images using joint sp.r.e representation

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Science china(Information Sciences) 2012年第3期55卷 590-599页

作者： LIU Huaping1,2,3 & SUN FuChun1,2,3 1Dep.r.ment of Computer Science and Technology, Tsinghua University, Beijing 100084, china 2State Key laboratory of Intelligent Technology and Systems, Beijing 100084, china 3Tsinghua national laboratory for Information Science and Technology, Beijing 100084, china 1. Dep.r.ment of Computer Science and Technology Tsinghua University Beijing 100084 China2. State Key Laboratory of Intelligent Technology and Systems Beijing 100084 China3. Tsinghua National Laboratory for Information Science and Technology Beijing 100084 China

Currently sp.r.e signal reconstruction gains considerable interest and is applied in many fields. In this pap.r. a similarity induced by joint sp.r.e representation is designed to construct the likelihood function of p.r.icle filter tracker so that the color visual spectrum and thermal spectrum images can be fused for object tracking. The proposed fusion scheme p.r.orms joint sp.r.e representation calculation on both modalities and the resultant tracking results are fused using min op.r.tion on the sp.r.e representation coefficients. In addition, a co-learning ap.r.ach is proposed to update the reference templates of both modality and enhance the tracking robustness. The proposed fusion scheme outp.r.orms state-of-the-art ap.r.aches, and its effectiveness is verified using OTCBVS database.

关键词： joint sp.r.e representation fusion tracking color image infrared image

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Mechanism for calcite dissolution and its contribution to development of reservoir p.r.sity and p.r.eability in the Kela 2 gas field,Tarim Basin,china

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Science china Earth Sciences 2008年第4期51卷 567-578页

作者： YU BingSong1,3, DONG HailLiang2,3 & rUAN Zhuang1,3 1 State Key laboratory of Geological processes and Mineral resources, china University of Geosciences, Beijing 100083, china 2 Dep.r.ment of Geology, Miami University,Oxford, OH 45056, USA 3 Geomicrobiology laboratory, china University of Geosciences, Beijing, 100083, china State Key laboratory of Geological processes and Mineral resources China University of Geosciences Beijing 100083 China Dep.r.ment of Geology Miami University Oxford OH 45056 USA Geomicrobiology laboratory China University of Geoscien

This study is undertaken to understand how calcite precipitation and dissolution contributes to depth-related changes in p.r.sity and p.r.eability of gas-bearing sandstone reservoirs in the Kela 2 gas field of the Tarim Basin, Northwestern china. Sandstone samples and p.r. water samples are col-lected from well KL201 in the Tarim Basin. Vertical profiles of p.r.sity, p.r.eability, p.r. water chem-istry, and the relative volume abundance of calcite/dolomite are constructed from 3600 to 4000 m below the ground surface within major oil and gas reservoir rocks. p.r.sity and p.r.eability values are in-versely correlated with the calcite abundance, indicating that calcite dissolution and precipitation may be controlling p.r.sity and p.r.eability of the reservoir rocks. p.r. water chemistry exhibits a sys-tematic variation from the Na2SO4 type at the shallow depth (3600-3630 m), to the NaHCO3 type at the intermediate depth (3630―3695 m),and to the CaCl2 type at the greater depth (3728―3938 m). The geochemical factors that control the calcite solubility include pH, temp.r.ture, pressure, Ca2+ concen-tration, the total inorganic carbon concentration (ΣCO2), and the type of p.r. water. Thermodynamic phase equilibrium and mass conservation laws are applied to calculate the calcite saturation state as a function of a few key p.r.meters. The model calculation illustrates that the calcite solubility is strongly dependent on the chemical composition of p.r. water, mainly the concentration difference between the total dissolved inorganic carbon and dissolved calcium concentration (i.e., [ΣCO2] -[Ca2+]). In the Na2SO4 water at the shallow depth, this index is close to 0, p.r. water is near the calcite solubility. Calcite does not dissolve or precipitate in significant quantities. In the NaHCO3 water at the intermedi-ate depth, this index is greater than 0, and p.r. water is sup.r.aturated with respect to calcite. Massive calcite precipitation was observed at this depth interval and

关键词： calcite dissolution p.r.sity thermodynamic Tarim Basin

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A Novel All-optical Wavelength ConverterBased on Self-pump Four-wave Mixing

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Chinese Journal of Lasers 2002年第2期11卷 61-65页

作者： CHEN Jianxiao CHEN Zhangyuan TAO Zhenning WU DemingXU Anshi WANG Ziyu(national laboratory on Local Optic-Fiber communication Networks &Advanced Optical communication Systems, Dep.r.ment of Electronics,peking University, Beijing 100871, china) Dep.r.ment of Electronics Peking University National Laboratory on Local Optic-Fiber Communication Networks & Advanced Optical Communication Systems 北京 100871

A novel scheme of all-optical wavelength converter(AOWC) based on dual pump four-wave mixing(Dp-FWM) was demonstrated. To sup.r.ss the ASE noise of the semiconductor optical amplifier (SOA), one of the two pumps was generated interiorly from a loop laser constructed mainly by tunable optical filter and SOA. The theoretical model and some exp.r.mental results were presented.

关键词： wavelength conversion four-wave mixing semiconductor optical amplifier self pump

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A constitutive model of frozen soil with damage and numerical simulation for the coupled problem

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Science china(physics,Mechanics & Astronomy) 2010年第4期53卷 699-711页

作者： ZHU ZhiWu, NING JianGuo& MA Wei 1 School of Mechanics and Engineering, Southwest Jiaotong University, chengdu 610031, china 2 State Key laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 100081, china 3 Key laboratory of Frozen Soil Engineering, CArEErI, CAS, Lanzhou 730000, china 1. School of Mechanics and Engineering Southwest Jiaotong University Chengdu 610031 China2. State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology Beijing 100081 China3. Key Laboratory of Frozen Soil Engineering CAREERI CAS Lanzhou 730000 China

Based on the microcosmic mechanics of composite materials, an elastic constitutive model for frozen soil with damage is presented. For frozen sandy soil with a range of ice contents and under a range of temp.r.ture conditions, quantitative results determined by this constitutive model agree with practically measured stress-strain curves. After numerically simulating the coupled water, temp.r.ture and stress fields of channel frozen and frozen roadbed using a self-developed finite-element routine, more accurate and practical calculation results for the temp.r.ture field coupled with stress, displacement and strain fields are obtained; the results match predictions and tests undertaken by earlier researchers. Our results supp.r. the reliability of our routine for calculating interdependent physical quantities of frozen soil and for describing the relationships between them. Our program can offer necessary constraints for engineering design and construction in p.r.afrost regions.

关键词： frozen soil microcosmic mechanics roadbed coupling stress field

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A New Three-Dimensional Sup.r.tructure in Bafertisite

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Acta Geologica Sinica(English Edition) 2011年第5期85卷 1028-1035页

作者： LI Guowu~*,XIONG Ming,SHI Nicheng and MA Zhesheng Crystal structure laboratory,national laboratory of Mineral Materials,china University of Geosciences (Beijing),Beijing 100083,china Crystal structure laboratory National Laboratory of Mineral Materials China University of Geosciences (Beijing) Beijing 100083 China *Correspondence: Guowu LI *Correspondence: Corresponding author. E-mail: liguowu@***

A new sup.r.tructure was found in bafertisite[(Ba;Na;);(Fe;Mn;Mg;);TiO [(Si;Ti;Al;Cr;);O;](OH;F;Cl;);]from Donghai County,Jiangsu province,*** occurrence of the sup.r.tructure reflections were observed by single crystal diffraction using a SMAr ApEX *** a;,b;and c;axis directions revealed extra weak reflection spots of the *** app.r.nt 2a,2b and 2c sup.r.tructure is monoclinic with unit cell a=10.6502（15） A,b= 13.7233（19）A,c=21.6897（3）A,α=90°,β=94.698（3）°,γ=90°,space group Cm,Z=*** c;extra weak reflections are ignored,the secondary sup.r.ell gave a cell a=10.6548（15）A,b=13.7284（19）A,c = 11.6900（17）A,α=90°,β=112.322（28）°,γ=90°,space group Cm,Z=*** basic subcell was obtained by ignoring all extra weak reflection spots and gave:a=5.3249（17）A,b=6.8669（22）A,c=10.8709（36） A,α=90°,β=94.740（62）°,γ=90°,space p2;/m,Z=*** sup.r.tructure has been refined to r = 0.063 for 7805[r;= 0.0266]unique reflections I>2δ（I）.The structure consists of an octahedra（O） sheet sandwiched between two heteropolyhedral（H） *** sheets consist of Ti-octahedra and twin tetrahedral disilicate groups[Si;O;].The O sheet comprises（Fe,Mg）O;*** large Ba cation is located in the interlayer *** refined structure shows Fe,Mg are p.r.ly *** shifting of the TiO;octahedron and SiO;tetrahedron sites in the sheet may be a consequence of the sup.r.tructure.

关键词： bafertisite sup.r.tructure crystal structure layered titanium silicate

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The Optimal Cross-section Design of the “Trapezoid-V” Shaped Drainage Canal of Viscous Debris Flow

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Journal of Mountain Science 2011年第1期8卷 103-107页

作者： YOU Yong Key laboratory of Mountain Hazards and Earth Surface process Chinese Academy of Sciences Chengdu 610041 China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China

Debris flow drainage canal is one of the most widely used engineering measures to prevent and manage debris flow *** shape and the sizes of the cross-section are imp.r.ant p.r.meters when design debris flow drainage ***,how to design the ap.r.priate shape and sizes of the cross-section so that the drainage canal can have the optimal drainage capacity is very imp.r.ant and few researched at home and *** study was conducted to analyze the hydraulic condition of a Trapezoid-V shaped drainage canal and optimize its *** assuming characteristic sizes of the cross-section,the pap.r.deduced the configuration p.r.meter of the cross-section of a Trapezoid-V shaped debris flow drainage *** theory analysis,it indicates that the optimal configuration p.r.meter is only related to the side slope coefficient and the bottom transverse slope *** this study,the Heishui Gully,a first-order tributary of the lower Jinsha river,was used as an example to design the optimal cross-section of the drainage canal of debris flow.

关键词： Optimal cross-section design Trapezoid- V shaped Drainage canal Viscous debris flow

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