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Multi-level decollement zones and detachment deformation of Longmenshan thrust belt,Sichuan Basin,southwest china

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Science china Earth Sciences 2008年第S2期51卷 32-43页

作者： TANG LiangJie1,2,3.YANG KeMing4,JIN WenZheng1,2,3.L ZhiZhou4 & YU YiXin1,2,3.1 state key Laboratory of Petroleum Resource and Prospecting,china University of Petroleum,{3. 102249,china 2 key Laboratory for Hydrocarbon Accumulation Mechanism,china University of Petroleum,Ministry of Education,{3. 102249,china 3.Basin and Reservoir Research Center,china University of Petroleum,{3. 102249,china 4 Southwest Division Company,SINOPEC,Chengdu 610081,china 1. state key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China 2. key Laboratory for Hydrocarbon Accumulation Mechanism China University of Petroleum Ministry of Education Beijing 102249 China 3. Basin and Reservoir Research Center China University of Petroleum Beijing 102249 China 4. Southwest Division Company SINOPEC Chengdu 610081 China

As is well known that many decollement layers were developed in the Longmenshan thrust belt,Si-chuan Basin,china. Through field investigation,explanation of seismic profiles and analysis of the balanced sections,we can divide the decollement zones into 3.categories: (1) the deep level decolle-ment zones,including the crust-mantle decollement layer,intracrustal decollement layer,and presinian basal decollement layer. The main structural styles of their deformation are the crust-mantle decoup-ling detachment deformation,the basal ductile shear deformation,etc.; (2) the middle level decollement zones,including the Cambrian-Ordovician decollement layer,the Silurian decollement layer,etc.,the main structural styles of their deformation are the isopachous fold,the angular fold,the saddle struc-ture,and the combination styles of them; and (3. the shallow level decollement zones,including the Xujiahe Formation decollement layer of Upper Triassic and the Jurassic decollement layers,the main structural styles of their deformation are the thrust-nappe tectonic,the pop-up,the triangle zone ,the duplex,etc. Multi-level decollement zones not only made the Longmenshan thrust belt develop many different deformation styles from deep place to shallow place,but also made some local areas have the superimposition of the tectonic deformation apparently. This study indicates that the multi-level de-collement zones have a very important effect on the shaping and evolution of the Longmenshan thrust belt.

关键词： decollement layer structural styles multi-level decollement zones Longmenshan thrust belt

SOLID PHASE TRANSITION OF SYNDIOTACTIC POLYSTYRENE IN SUPERCRITICAL CO_2

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Chinese Journal of Polymer Science 2002年第3期20卷 191-196页

作者： Yu-ying Li Jia-song He state key Laboratory of Engineering Plastics, Center for Molecular Science, Institute of Chemistry Chinese Academy of Sciences, beijing 100080{3. Chinese Acad Sci Inst Chem Ctr Mol Sci State Key Lab Engn Plast Beijing 100080 Peoples R China

Solid phase transition of the a form crystals to the 3.form crystals in syndiotactic polystyrene (sPS) samples has occurred in supercritical CO2. This transformation is different from those detected under other conditions. The effects of some factors (e.g. time, temperature, and pressure) on the solid phase transformation of sPS in supercritical CO2 were analyzed in detail. Experimental results show that longer time, higher temperature or higher pressure favors the transformation of the a form crystals to the beta form crystals.

关键词： solid phase transition syndiotactic polystyrene supercritical CO2

PRINCIPLES OF RIVER TRAINING AND MANAGEMENT

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International Journal of Sediment Research 2007年第4期22卷 247-262页

作者： Zhaoyin WANG1, Shimin TIAN2, Yujun YI3. and Guoan YU4 1 Prof., state key Laboratory of Hydroscience and Engineering, Tsinghua University, beijing, 100084,{3. 2 Ph. D.,{3. Institute of Water Resources and Hydro-Power Research, beijing 100044,{3.. 3.Ph. D., state key Laboratory of Hydroscience and Engineering, Tsinghua University, beijing, 100084,{3. 4 Ph. D., state key Laboratory of Hydroscience and Engineering, Tsinghua University, beijing, 100084,{3. Tsinghua Univ State Key Lab Hydrosci & Engn Beijing 100084 Peoples R China china Inst Water Resources & Hydropower Res Beijing 100044 Peoples R China

River regulation and river training have been performed for various purposes and negative effects have been shown in numerous cases. In some cases the negative effects are so serious that humans have to consider to "renaturalize" the regulated rivers. Only by using the strategy of integrated river management the diverse river uses and natural fluvial processes and ecological systems may be harmonized. Based on analysis of case studies and data collected from literatures this paper presents the concept of integrated river management and four principles of river training. The integrated river management comprises: 1) taking the watershed, upper stream basin including the tributaries, middle and lower reaches and the estuary as an integrated entity in the planning, design and management; and 2) mitigating or controlling the negative impacts on hydrology, erosion and sedimentation, fluvial processes, land use and river use, environment and ecology while in achieving economic benefit from water resources development, flood safety management and hydropower exploitation. River training and management should be in accordance with the four principles: 1) extending the duration of river water flowing on the continent, which may be achieved by extending the river course or reducing the flow velocity; 2) controlling various patterns of erosions and reducing the sediment transportation in the rivers; 3. increasing the diversity of habitat and enhancing the connectivity between the river and riparian waters; and 4) restoring natural landscapes.

关键词： River training Integrated river management Sediment Erosion control Ecological and landscape restoration

MODIFICATION OF EPOXY RESIN WITH POLYSILOXANE BEARING PENDANT QUATERNARY AMMONIUM GROUPS

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Chinese Journal of Polymer Science 2002年第6期20卷 537-541页

作者： Zuo-xin Huang Ying Huang Yun-zhao Yu The state key Laboratory of Engineering Plastics, Institute of Chemistry Chinese Academy of Sciences, beijing 100080{3. Chinese Acad Sci Inst Chem State Key Lab Engn Plast Beijing 100080 Peoples R China

Polysiloxane bearing pendant quaternary ammonium groups (PSI) was used to modify the surface properties of epoxy resins. In the cured resin, PSI formed the dispersed phase. Remarkable enrichment and gradient distribution of polysiloxane on the surface region of the epoxy resins were demonstrated by XPS analysis. The composition and properties of the surface of PSI-modified epoxy resin, which is in contact with the mold, are dependent on the material of the mold. Through the incorporation. of PSI, epoxy resins with low surface energy and low friction coefficient were obtained. Polysiloxane with lower ionic group content shows a higher degree of enrichment on the resin surface and leads to a higher contact angle against water, while the polysiloxane having optimum compatibility with the epoxy resin shows a greater effect in reducing the static friction coefficient of the resin against glass.

关键词： polysiloxane epoxy resin surface composition friction coefficient

Improved multi-pass fast correlation attacks with applications

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Science china(Information Sciences) 2011年第8期54卷 1635-1644页

作者： ZHANG Bin & FENG DengGuo state key Laboratory of Information security,Institute of Software,Chinese Academy of Sciences,{3. 100190,china 1. state key Laboratory of Information security Institute of Software Chinese Academy of Sciences Beijing 100190 China

In this paper we propose two new algorithms for multi-pass fast correlation attacks on stream *** first algorithm aims at fast symbol-wise decoding in the circumstances that the noise is not very high and we have little resource for *** second algorithm deals with the practical decoding problem in the high noise and limited keystream *** new algorithms are applicable to arbitrary form LFSR and compare favorably to the previously known algorithms in the scenarios under *** applications,we demonstrate new key recovery attacks on one-level Bluetooth E0 and LILI-128,*** 2 3. -bit keystream and 2 28-byte memory,our attack against one-level E0 needs 2 3..1 *** 2 24-bit keystream and 2 24.5 -byte memory,our attack on LILI-128 has time complexity 2 70.6 operations.

关键词： stream cipher fast correlation attacks linear feedback shift register (LFSR) Bluetooth E0 LILI-128

Sediment pollution and its effect on fish through food chain in the Yangtze River

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International Journal of Sediment Research 2008年第4期23卷 338-347页

Suspended sediment adsorbs pollutants from flowing water in rivers and deposits onto the bed. However, the pollutants accumulated in the river bed sediment may affect the bio-community through food chain for a long period of time. To study the problem the concentration of heavy metals (Cr, Cd, Hg, Cu, Fe, Zn, Pb and As) in water, sediment, and fish/invertebrate were investigated in the middle and lower reaches of the Yangtze River during 2006-2007. The concentrations of heavy metals were 100-10,000 times higher in the sediment than in the water. Benthic invertebrates had relatively high concentrations of heavy metals in their tissues due to their proximity to contaminated sediments. Benthic invertivore fish had moderately high concentrations of heavy metals whereas phytoplanktivore fish, such as the silver carp, accumulated the lowest concentration of heavy metals. The concentrations of Cu, Zn, and Fe were higher than Hg, Pb, Cd, Cr, and As in the tissue samples. The concentration of heavy metals was lower in the river sediments than in the lake sediments. Conversely, the concentration of heavy metals was higher in river water than in lake water. While a pollution event into a water body is often transitory, the effects of the pollutants may be long-lived due to their tendency to be absorbed in the sediments and then released into the food chain. The heavy metals were concentrated in the following order: bottom material > demersal fish and benthic fauna > middle-lower layer fish > upper-middle layer fish > water.

关键词： Sediment pollution Heavy metal Fish Invertebrate Yangtze River

security model and modular design of fair authentication key exchange protocols

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Science china(Information Sciences) 2010年第2期53卷 278-287页

作者： FENG DengGuo & CHEN WeiDong state key Laboratory of Information security, Institute of Software, Chinese Academy of Sciences, {3. 100190, china 1. state key Laboratory of Information security Institute of Software Chinese Academy of Sciences Beijing 100190 China

It is traditionally assumed that the legal two parties in authentication key exchange (AKE) communications are both credible. However, in more and more network applications nowadays, it is often required that such protocols be run under the circumstances where ones do not trust in each other. Therefore, in this paper we propose the idea of fair authentication key exchange (FAKE), which has not only the basic properties of AKE protocols, but also some new properties: the "session proof" embedded in the input of protocols by the customer; and if not revealed, the protocols have the deniability, otherwise the transcript of protocol is binding for the identifications. Such a method is capable of solving the contradiction between protecting privacy and the dissension on network service. Then the security model of FAKE protocols is formulated systematically and a flaw of the security model of current signature schemes proposed by Kudla is also corrected. Finally, a kind of FAKE protocol based on current signature schemes is designed and the mBJM-AK security, conditional deniability and fairness of FAKE protocols are proved in the random oracle model.

关键词： authentication key exchange protocols deniability fairness concurrent signature provable security

Attention and available long-term memory in an activation-based model

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Science china(Life Sciences) 2010年第6期53卷 743-752页

作者： LIU ZhaoMin1,GUO ChunYan2,3.& LUO Liang4 1 School of Sociology,china University of Political Science and Law,beijing 102249,china 2 beijing key Laboratory of Learning and Cognition,Department of Psychology,Capital Normal University,beijing 100048,china 3.key Laboratory of Mental Health,Chinese Academy of Sciences,beijing 100101,china 4 state key Laboratory of Cognitive Neuroscience and Learning,beijing Normal University,beijing 100875,china 1. School of Sociology China University of Political Science and Law Beijing 102249 China2. Beijing Key Laboratory of Learning and Cognition Department of Psychology Capital Normal University Beijing 100048 China3. Key Laboratory of Mental Health Chinese Academy of Sciences Beijing 100101 China4. State Key Laboratory of Cognitive Neuroscience and Learning Beijing Normal University Beijing 100875 China

The influence of attention on memorizing related items and on available long-term memory (ALTM) was explored,showing that N400 of no-memory items was more negative than that of the memory *** results of the category comparison task indicated that information processing under attention-driven in WM determined the availability of related long-term memory,i.e.,specific content,which was formerly concerned or ignored,yielding different indirect semantic priming *** indicate that the orientation of conceptual attention leads the related representations of LTM to diverse activation patterns,supporting the activation-based model.

关键词： activation-based model attention available long-term memory event-related potentials

Monitoring of rice crop using ENVISAT ASAR data

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Science china Earth Sciences 2006年第7期49卷 755-763页

作者： DONG Yanfang1, 2, SUN Guoqing1,3.& PANG Yong4 1. state key Laboratory of Remote Sensing Science, Institute of Remote Sensing Applications, Chinese Academy of Sciences, beijing 100101,{3. 2. Graduate University of Chinese Academy of Sciences, beijing 10003.,{3. 3. Department of Geography, University of Maryland, College Park, MD 20742, USA 4. Forest Remote Sensing Lab, Research Institute of Forest Resource and Information Technology, Chinese Academy of For-estry, beijing 100091,{3. 1. state key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China 2. Graduate University of Chinese Academy of Sciences Beijing 100039 China 3. Department of Geography University of Maryland College Park MD 20742 USA 4. Forest Remote Sensing Lab Research Institute of Forest Resource and Information Technology Chinese Academy of Forestry Beijing 100091 China

Because of the cloudy conditions during the rice growth period, rice is one of the agri-cultural crops most suited to monitoring with the SAR instruments. Backscatter response measured by SAR is correlated with rice conditions, including height, density, biomass and structure, which are variable at different growing stages. In this paper, multi-date ENVISAT ASAR Alternating Polarization Mode (APMode) imageries were acquired during the rice crop growing cycle. At the same time, the rice parameters were measured in field. A continuous canopy model was used to compute the back-scattering from rice fields during the growth cycle, and the relationship between rice parameters and radar backscattering coefficients from both ASAR and modeling was analyzed. The effects of polari-zation, incidence angle and polarization on radar backscattering coefficients were analyzed. It was found that simulated radar backscatter has similar trends as ASAR data. This will be meaningful for the further research of rice parameters estimation from ASAR data. Different features show signifi-cantly different signatures in ASAR images and they follow some certain laws, so rice area can be accurately mapped by using multi-temporal SAR images, then rice yield can be estimated.

关键词： rice, ASAR, radar backscattering, model.