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Science china Earth Sciences 2004年第3期47卷 247-254页

作者： ZHU Jingquan1, LI Yongtie2, JIANG Maosheng1 & CHEN Daizhao1 1. institute of geology and Geophysics, Chinese Academy of Sciences, beijing 100029, china 2. Research institute of Petroleum Exploration and Development, CNPC, beijing 100083, china institute of geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Res. Inst. Petroleum Explor./Devt. CNPC Beijing 100083 China

The d 13C values of Lower Cretaceous Aptian-Albian platform-type carbonates in the Cuoqin Basin, North Tibet vary between 2.4. and 5.4.. The mean value is 3.93. The values are not only provided with positive excursion, but also 1.17 higher than those of con-temporaneous pelagic carbonates which possess pretty high d 13C values. The origin is ap-proached. During the oceanic anoxic events, a great number of organisms were rapidly buried, causing the increase of the d 13C value of oceanic total dissolved carbon (TDC) and generally promoting the values of marine carbonates. After that, owing to the organisms undergoing dif-ferent isotopic fractionation in the paleo-ocean with stratified structure, d 13C values of shallow sea carbonate were obviously higher than those of pelagic carbonates.

关键词： shallow water carbonate, stable carbon isotope, paleooceanography, Aptian-Albian stage, Cuoqin Basin.

Thermal Activation Analyses of Dynamic FractureToughness of High Strength Low Alloy Steels

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Journal of Materials Science & Technology 2001年第2期17卷 215-218页

作者： Cunjian LI and Shaohua LI Welding Research Department, Central Iron & Steel Research institute, beijing 100081, china Yuqing DENG State administration of Metallurgical Industry, beijing 100711, china Dept. of Welding Res. Central Iron and Steel Res. Inst. Beijing 100081 China

A formula is derived for determining the influence of temperature and loading rate on dynamic fracture toughness of a high strength low alloy steel (HQ785C) from thermal activation analysis of the experimental results of three-point bend specimens as well as introducing an Arrhenius formula. It is shown that the results obtained by the given formula are in good agreement with the experimental ones in the thermal activation region. The present method is also valuable to describe the relationship between dynamic fracture toughness and temperature and loading rate of other high strength low alloy steels.

关键词： test GB Thermal Activation Analyses of Dynamic FractureToughness of High Strength Low Alloy Steels

Information content security on the Internet:the control model and its evaluation

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Science china(Information Sciences) 2010年第1期53卷 30-49页

作者： FANG BinXing1, GUO YunChuan2,3 & ZHOU Yuan4.1School of Computer, beijing University of Posts and Telecommunications, beijing 100029, china 2institute of Computing Technology, Chinese Academy of Sciences, beijing 100190, china 3Graduate University of Chinese Academy of Sciences, beijing 10004., china 4.ational Computer Network Emergency Response Technical Team/Coordination Center of china, beijing 100029, china School of Computer Beijing University of Posts and Telecommunications Beijing China institute of Computing Technology Chinese Academy of Sciences Beijing China Graduate University of Chinese Academy of Sciences Beijing China National Computer Network Emergency Response Technical Team/Coordination Center of china Beijing China

Flooding of harmful information on the Internet seriously endangers the physiological and mental health of teenagers. Due to the user-friendliness of the Internet as well as the difficulty in the authentication for the access of specific categories of information, curbing the transmission of harmful information, i.e., assuring the information content security (ICS), has become a reasonable yet challenging alternative. At present, there is an urgent need to develop a systematic model that can effectively carry out the curbing. In fact, curbing the transmission of harmful information by way of filtering can be modeled by access control. In the paper, based on the three core-elements of communication, namely, "Who communicates with whom", "How do they communicate" and "What is the content of communication", we propose a control model, called ICCON. Unlike the existing access control, the reference monitor (RM) of our model is placed in the transmission channel, and moreover, an evaluation frame is proposed, through which the effectiveness of the RM in controlling information transmission on the Internet can be quantitatively evaluated.

关键词： content security access control quantitative evaluation

Comparison of eastern paleo-Tethyan ophiolites and its geodynamic significance--Evidence from Dur'ngoi ophiolite

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Science china Earth Sciences 2004年第4期47卷 378-384页

作者： CHEN Liang1,2, SUN Yong1,2, PEI Xianzhi2, Feng Tao2 & Zhang Guowei2 1. Open Laboratory of Continental Dynamics, Ministry of Education, Northwest University, Xi抋n 710069, china 2. institute of geology and Geophysics, Chinese Academy of Sciences, beijing 100029, china Open Laboratory of Continental Dynamics Ministry of Education Northwest University Xi’an China institute of geology and Geophysics Chinese Academy of Sciences Beijing China

Nd-Pb isotopic geochemistry of metabasalt from Dur抧goi ophiolite, Qinghai Prov-ince, NW china reveals the presence of DMM mixing with EMII components in its upper mantle source, which is comparable with present Indian MORB. Comparisons indicate that the geo-chemistry, chronology and source characteristics of Dur抧goi ophiolite coincide with Pa-leo-tethyan ophiolites from 揝anjiang?area. Together with evidences from regional geology in adjacent areas, this study proves that independent paleo-tethyan basins evolved contemporarily, the dynamics of which is attributed to the interaction of mantle plume with over-riding lithosphere.

关键词： ophiolite, Paleo-Tethys, DUPAL anomaly, Indosinian movement.

Distribution and characteristics of gravelly soil liquefaction in the Wenchuan M_s 8.0 earthquake

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earthquake Engineering and Engineering Vibration 2010年第2期9卷 167-175页

作者： Cao Zhenzhong1,Hou Longqing2,Xu Hongmei2 and Yuan Xiaoming1 1. institute of Engineering Mechanics,china earthquake administration,Harbin 150080,china 2. East china institute of Technology,Fuzhou 34.000,china institute of Engineering Mechanics China Earthquake Administration Harbin China East china institute of Technology Fuzhou China institute of Engineering Mechanics Chinese Earthquake Administration Harbin China

In this paper,a distribution map of gravelly soil liquefaction that was caused by the Wenchuan M8.0 earthquake in china is proposed based on a detailed field investigation and an analysis of geological soil profiles. The geological background of the earthquake disaster region is summarized by compiling geological cross sections and borehole logs. Meanwhile,four typical liquefied sites were selected to conduct sample drillings,dynamic penetration tests (DPT),and shear wave velocity tests,to understand the features of liquefied gravelly soil. One hundred and eighteen (118) liquefied sites were investigated shortly after the earthquake. The field investigation showed:(1) sandboils and waterspouts occurred extensively,involving thousands of miles of farmland,120 villages,eight schools and five factories,which caused damage to some rural houses,schools,manufacturing facilities and wells,etc.; (2) the Chengdu plain is covered by a gravelly soil layer with a thickness of 0 m to 54. m according to the geological cross sections; (3) there were 80 gravelly soil liquefied sites in the Chengdu plain,shaped as five belt areas that varied from 20 km to 4. km in length,and about ten gravelly soil liquefied sites distributed within Mianyang area; and (4. the grain sizes of the sampled soil were relative larger than the ejected soil on the ground,thus the type of liquefied soil cannot be determined by the ejected soil. The gravelly soil liquefied sites are helpful in enriching the global database of gravelly soil liquefaction and developing a corresponding evaluation method in further research efforts.

关键词： gravelly soil liquefaction borehole soil profile geological cross section grain size distribution Wenchuan earthquake

Prediction model for spring dust weather frequency in North china

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Science china Earth Sciences 2008年第5期51卷 709-720页

作者： LANG XianMei Center for Disastrous Climate Research and Prediction, institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 100029, china Center for Disastrous Climate Research and Prediction Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

It is of great social and scientific importance and also very difficult to make reliable prediction for dust weather frequency (DWF) in North china. In this paper, the correlation between spring DWF in beijing and Tianjin observation stations, taken as examples in North china, and seasonally averaged surface air temperature, precipitation, Arctic Oscillation, Antarctic Oscillation, South Oscillation, near surface meridional wind and Eurasian westerly index is respectively calculated so as to construct a prediction model for spring DWF in North china by using these climatic factors. Two prediction models, i.e. model-I and model-II, are then set up respectively based on observed climate data and the 32-year (1970 -2001) extra-seasonal hindcast experiment data as reproduced by the nine-level Atmospheric General Circulation Model developed at the {4. of Atmospheric Physics (IAP9L-AGCM). It is indicated that the correlation coefficient between the observed and predicted DWF reaches 0.933 in the model-I, suggesting a high prediction skill one season ahead. The corresponding value is high up to 0.94. for the subsequent model-II, which involves synchronous spring climate data reproduced by the IAP9L-AGCM relative to the model-I. The model-II can not only make more precise prediction but also can bring forward the lead time of real-time prediction from the model-I’s one season to half year. At last, the real-time predictability of the two models is evaluated. It follows that both the models display high prediction skill for both the interannual variation and linear trend of spring DWF in North china, and each is also featured by different advantages. As for the model-II, the prediction skill is much higher than that of original approach by use of the IAP9L-AGCM alone. Therefore, the prediction idea put forward here should be popularized in other regions in china where dust weather occurs frequently.

关键词： spring dust weather frequency prediction model iap9l-agcm hindcast experiment real-time prediction

Provincialism of the late Middle through middle Late Cambrian paraconodonts and protoconodonts

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Chinese Science Bulletin 2001年第5期46卷 433-438页

作者： DONG XipingDepartment of geology, Peking University, beijing 100871, china Laboratory of Paleobiology & Stratigraphy, Nanjing institute of geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, china Department of geology Peking University Beijing China Laboratory of Paleobiology & Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China

Quantitative paleoprovincialism is studied, using a coefficient of similarity (CS) formula. The results indicate that the provincialism of the late Middle through middle Late Cambrian paraconodonts and protoconodonts did exist. The provincialism of Ordovician conodonts can be traced back to late Middle Cambrian. The North china Province and South china Province can be recognized in late Middle Cambrian, whereas the North china Province, South china Province and Balitca Province can be recognized respectively in early Late Cambrian and middle Late Cambrian. The possibility that the larger units of provincialism, i.e. Faunal Regions existed in the areas mentioned above is discussed. It is inferred that the Midcontinent Faunal Region and the Atlantic Faunal Region had existed in early Late Cambrian and middle Late Cambrian. The North china Province was the secondary unit of provincialism in the Midcontinent Faunal Region, while the Baltica Province was that in the Atlantic Faunal Region. The South china

关键词： paraconodonts and protoconodonts provincialism late Middle Cambrian through middle Late Cambrian.

“Tali Glaciation” on Massif Diancang

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Science china Earth Sciences 2007年第11期50卷 1685-1692页

作者： YANG JianQiang1, CUI ZhiJiu2, YI ChaoLu1, SUN JiMin3 & YANG LiRong3 1 institute of Tibetan Plateau Research, Chinese Academy of Sciences, beijing 100085, china 2 College of Environmental Sciences, Peking University, beijing 100871, china 3 institute of geology and Geophysics, Chinese Academy of Sciences, beijing 100029, china institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China College of Environmental Sciences Peking University Beijing China institute of geology and Geophysics Chinese Academy of Sciences Beijing China

The term of ''Tali Glaciation'' is nominated from Massif Diancang in Yunnan Province. The confusing process of the term''s being put forward is confirmed through literature checking. Based on several times of field trip, the glacial landforms in this region are studied in detail, and the magnitude of the glaciation was determined. According to the numerical ages from TL, AIMS ^(14.C and OSL dating, the earliest glacial advance on Massif Diancang occurred at 30—4. ka BP, followed by the advances at the last stage of the last glaciation, the late glacial and neoglations in turn, until glaciers vanished at 1.2—1.5 ca. a BP in this region. It can be concluded that glaciers were limited above 3600 m a.s.l., and no glaciers existed on the lower part and adjacent mountains since the last glaciation.

关键词： Massif Diancang,Tali Glaciation,glacial landform,glaciation sequence,numerical dating

The influence of tropical Indian Ocean warming on the Southern Hemispheric stratospheric polar vortex

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Science china Earth Sciences 2009年第3期52卷 323-332页

作者： LI ShuangLin Nansen-Zhu International Research Centre, institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 100029, china Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

During the past decades, concurrent with global warming, most of global oceans, particularly the tropical Indian Ocean, have become warmer. Meanwhile, the Southern Hemispheric stratospheric polar vortex (SPV) exhibits a deepening trend. Although previous modeling studies reveal that radiative cooling effect of ozone depletion plays a dominant role in causing the deepening of SPV, the simulated ozone-depletion-induced SPV deepening is stronger than the observed. This suggests that there must be other factors canceling a fraction of the influence of the ozone depletion. Whether the tropical Indian Ocean warming (IOW) is such a factor is unclear. This issue is addressed by conducting ensemble atmospheric general circulation model (AGCM) experiments. And one idealized IOW with the amplitude as the observed is prescribed to force four AGCMs. The results show that the IOW tends to warm the southern polar stratosphere, and thus weakens SPV in austral spring to summer. Hence, it offsets a fraction of the effect of the ozone depletion. This implies that global warming will favor ozone recovery, since a warmer southern polar stratosphere is un-beneficial for the formation of polar stratospheric clouds (PSCs), which is a key factor to ozone depletion chemical reactions.

关键词： tropical Indian Ocean warming Southern Hemispheric stratospheric polar vortex atmospheric general circulation model ensemble experiments planetary wave

Ambient noise near the sea-route

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Science china(Physics,Mechanics & Astronomy) 2009年第1期52卷 40-45页

作者： HE Li1,2, LI ZhengLin1,3 & PENG ZhaoHui1 1 National Laboratory of Acoustics, institute of Acoustics, Chinese Academy of Sciences, beijing 100190, china 2 institute of {4. and Geophysics, Chinese Academy of Sciences, beijing 100029, china 3 NanHai Laboratory of Acoustics, institute of Acoustics, Chinese Academy of Sciences, Haikou 570206, china National Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Beijing China institute of geology and Geophysics Chinese Academy of Sciences Beijing China NanHai Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Haikou China

Ambient noise data measured in an experiment conducted in shallow water near a sea-route were analyzed. It was observed that, at low frequency, the horizontal correlation has an obvious difference from that predicted by the classical ambient noise model. The theoretical analyses show that this phenomenon is caused by wind noise together with the discrete shipping noise nearby. An ambient noise model was proposed to include the effects caused by both the noise sources. Data measured at different times verify that the proposed model can be used to forecast the ambient noise field in shallow water near the sea-route.

关键词： ambient noise model horizontal correlation discrete ships