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Isotopic compositions of small shelly fossil Anabarites from Lower Cambrian in Yangtze Platform of South China: Implications for palaeocean temperature

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Progress in Natural Science:Materials International 2007年第10期17卷 1185-1191页

作者： Chen Yongquan1.2, Jiang Shaoyong1. Ling Hongfei1. Yang Jinghong1.and Wan Defan3.1. State Key Laboatory for Mineral Deposits Research and {1. for Marine Geochemistry Research, Department of Earth Sciences, Nanjing University, Nanjing 21.093. China 2. Tarim Oilfield Company Exploration & Development Research Institute, Ku’erle 841.00, China 3. Institute of Mineral Resources, Chinese Academy of Geological Sciences, beijing 1.003., China) State Key Laboatory for Mineral Deposits Research and center for Marine Geochemistry Research Department of Earth Sciences Nanjing University Nanjing 210093 China arim Oilfield Company Exploration & Development Research Institute Ku’erle 841000 China Institute of Mineral Resources Chinese Academy of Geological Sciences Beijing 100037 China

Anabarites belong to small shelly fossils (SSF), which occur widely in the Lower Cambrian strata of Yangtze Platform in South China. They are phosphate shell in composition and represent the earliest stage of the Cambrian bioradiation of Bilateria, the so-called "Cambrian Explosion". In this study, we attempted to separate Anabarites fossils from Lower Cambrian dolostones, and we obtained samples of both the fossils (SSF) and the granular phosphates (GP). Isotopic analyses were performed on samples of SSF, GP, and matrix dolostone (DH-23.. The results showed that the δ3.Si values of the quartz filling in fossils celoms, and the siliceous materials in granular phosphates are -0.6‰ and -0.7‰, which is different from normal sedimentary siliceous rocks from the Lower Cambrian strata (0—0.7‰) as reported by Li et al., but is consistent with the data for siliceous rocks and cherts of submarine hydrothermal origin. It is likely that a later hydrothermal replacement could have taken place in the SSF-bearing sedimentary rocks. The oxygen isotope values of the phosphate of SSF and GP are 1..8‰ and 1..0‰, respectively. These are significantly higher than the Neoproterozoic phosphate ores (1..9‰—1.0}9‰) as reported by Ling et al., hence, late diagenesis and hydrothermal replacement may not have caused a significant change in the oxygen isotope compositions of the small shelly fossils, and the calculated temperatures (25.4—26.3.) for palaeo-seawater using a SSF phosphate oxygen isotope thermometer are therefore considered here as the upper limit of seawater temperature in the Early Cambrian ocean of the Yangtze Platform.

关键词： Anabarites oxygen isotope silicon isotope paleo-temperature.

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Synthesis of superheavy nuclei with ^(23.)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,{1. Normal University,{1. 1.0875,China 2 Department of Physics,{1. Normal University,{1. 1.0875,China 3.China Institute of Atomic Energy,{1. 1.241.0}China 4 center of Theoretical Nuclear Physics,national Laboratory of Heavy Ion Accelerator of Lanzhou,Lanzhou 73.000,China Key Laboratory of Beam Technology and Material Modification of Ministry of Education Beijing Normal University Beijing 100875 China Department of Physics Beijing Normal University Beijing 100875 China China Institute of Atomic Energy Beijing 102413 China center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000 China

The production of superheavy nuclei with Z=1.8-1.6 via hot fusion reactions of the neutron-rich projectiles with 23.U 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 = 1.2 and 1.5 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 23.U target

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Research on the Long Time Swelling Properties of Poly (vinyl alcohol)/Hydroxylapatite Composite Hydrogel

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Journal of Bionic Engineering 2009年第1期6卷 22-28页

作者： De-kun Zhang~(1.3., Da-gang Wang~2, Jun-jie Duan~(1.3., Shi-rong Ge~(2,3.1. School of Materials Science and Engineering, China University of Mining and Technology, Xuzhou 221.1., P. R. China2. School of Mechanical and Electrical Engineering, China University of Mining and Technology, Xuzhou 221.1., P. R. China3. Biotribology center, national Key Laboratory of Tribology, Tsinghua University, beijing 1.0083. P. R. China [a]School of Materials Science and Engineering China University of Mining and Technology Xuzhou 221116 P. R. China [b]School of Mechanical and Electrical Engineering China University of Mining and Technology Xuzhou 221116 P. R. China [c]Biotribology Center National Key Laboratory of Tribology Tsinghua University Beijing 100083 P. R. China

Poly(vinyl alcohol)/hydroxylapatite(PVA/HA)composite hydrogel was prepared by repeated freezing and *** water loss properties of the resultant hydrogel were investigated by using optical *** time immersion tests of PVA/HA composite hydrogel were carried out in the diluted calf serum solution to study the change laws of swelling properties with the freezing-thawing cycles and HA *** micro-morphologies of PVA/HA composite hydrogel after long time immersion were observed by means of the high-accuracy 3. *** results show that the swelling process of PVA/HA composite hydrogel is the converse process of its water *** time swelling ratio curves of PVA/HA composite hydrogel in the calf serum solution are manifested as four stages of quick increase,decrease,slow decrease and stable balance,and its equilibrium swelling ratio decreases with the increase of freezing-thawing cycles and HA *** is revealed that the network structure of the composite hydrogel immersed for a long period is significantly improved with the increase of HA content. Perfect network structures of PVA/HA composite hydrogel as well as full and equilibrium tissues after swelling equilibrium are obtained when the HA content is 3. and the number of freezing-thawing cycles is 7.

关键词： poly (vinyl alcohol) hydroxyapatite composite hydrogel swelling property morphology

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Systematic distortion in cosmic microwave background maps

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Science China(Physics,Mechanics & Astronomy) 2009年第5期52卷 804-808页

作者： LIU Hao 1.3.&LI TiPei 1.2 1.ey Laboratory of Particle Astrophysics,Institute of High Energy Physics,Chinese Academy of Sciences,{1. 1.0049,China 2center for Astrophysics,Tsinghua University,{1. 1.0084,China 3.Graduate University of Chinese Academy of Sciences,{1. 1.0049,China Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China center for Astrophysics Tsinghua University Beijing 100084 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

To minimize instrumentally the induced systematic errors,cosmic microwave background(CMB)anisotropy experiments measure temperature differences across the sky using pairs of horn antennas, temperature map is recovered from temperature difference obtained in sky survey through a map-making *** inspect and calibrate residual systematic errors in the recovered temperature maps is important as most previous studies of cosmology are based on these *** analyzing pixel-ring coupling and latitude dependence of CMB temperatures,we find notable systematic devia- tion from CMB Gaussianity in released Wilkinson Microwave Anisotropy Probe(WMAP)*** detected deviation cannot be explained by the best-fit LCDM cosmological model at a confidence level above 99%and cannot be ignored for a precision cosmology study.

关键词： cosmology cosmic microwave background methods data analysis

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Solar release time of solar energetic particles and associated acceleration source in corona

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Chinese Science Bulletin 2008年第2期53卷 161-168页

作者： LE GuiMing1.2,3.4, TANG YuHua1.& HAN YanBen4 1.Department of Astronomy, Nanjing University, Nanjing 21.093. China 2 Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites, China Meteorological Administration, beijing 1.0081. China 3.national center for Space Weather, China Meteorological Administration, beijing 1.0081. China 4 national Astronomical Observatories, Chinese Academy of Sciences, beijing 1.001., China Department of Astronomy Nanjing University Nanjing China Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites China Meteorological Administration Beijing China national {1. for Space Weather China Meteorological Administration Beijing China national Astronomical Observatories Chinese Academy of Sciences Beijing China

Solar energetic particles (SEPs) are accelerated in corona at an early phase of solar energetic particle events (SEPE). The acceleration mechanism of SEPs in corona can only be inferred from an analysis of multi-band observational data, as the observation of SEPs is usually made around 1.U. In this context, people have investigated spectrums, charge state, solar release time (SRT), and multi-band data of SEPEs, in an attempt to judge the acceleration mechanism of SEPs. The SRT computation of SEPs is an important and commonly used approach to study the acceleration mechanism of SEPs in corona. This paper reviews some important findings concerning the SRT computation of SEPs, and analyzes different merits of each approach for such calculation, based on a range of SEPE case studies. This paper also analyzes and discusses both possible and actual acceleration mechanisms of a number of SEPEs, by calculating the SRT of the SEPEs. Finally, the paper summarizes the possible problems in studying an acceleration mechanism of SEPEs inferred from the SRT of SEP.

关键词：阳光释放时间加速度电晕太阳耀斑

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Sorption behavior of U(VI), ^(23.)U(VI) and ^(23.)U(VI) onto fracture-filling clays in Beishan granite, Gansu: Application to selecting the site of high-level radwaste repository in China

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Science China Earth Sciences 2005年第10期48卷 1649-1655页

作者： MIN Maozhong1.2, LUO Xingzhang3. WANG Ju4, JIN Yuanxin4 & WANG Rucheng1.1. Department of Earth Sciences, State Key Laboratory of Mineral Deposit Research, Nanjing University, Nanjing 21.093. China 2. center of Materials Analysis, Nanjing University, Nanjing 21.093. China 3. Department of Environmental Science and Engineering, Nanjing University, Nanjing 21.093. China 4. beijing Geology Institute, Nuclear Industry, beijing 1.0029, China Department of Earth Sciences State Key Laboratory of Mineral Deposit Research Nanjing University Nanjing China center of Materials Analysis Nanjing University Nanjing China Department of Environmental Science and Engineering Nanjing University Nanjing China beijing Geology Institute Nuclear Industry beijing China

The first results of sorption experiments of U(VI), 23.U(VI) and 23.U(VI) onto original (unpurified) fracture-filling clays from No.1.monzonitic granite intrusion, Beishan area, Gansu Province, China are reported. The monzonitic granite intrusion is a potential location for a high-level radwaste (HLW) repository in China. The present experimental results show that the maximum U(VI) sorption reached 92% at near-neutral pH and the distribution coefficient (Kd) was 1.26 mL/g. A high sorption capacity of the fracture-filling clays in host rock on radioactive ele-ments is necessary for HLW deep geological disposal repository. No preferential sorption of 23.U onto the clays was found. Finally, the sorption of U(VI) onto the clays was also modeled using a surface complexation model.

关键词： HLW geological disposal repository, granite, uranium, radionuclide, clay, sorption.

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Science China Earth Sciences 2004年第10期47卷 886-895页

作者： TANG Liangjie1.2, JIA Chengzao3. PI Xuejun4, CHEN Suping1.2, WANG Zhiyu5, XIE Huiwen4 1. Key Laboratory for Hydrocarbon Accumulation of Education Ministry, {1. 1.2249, China 2. Basin & Reservoir Research center, University of Petroleum, {1. 1.2249, China 3. PetroChina Company Limited, {1. 1.001., China 4. Tarim Oilfield Company, PetroChina Company Ltd., Kurle 841.00, China 5. Department of Geology, University of Petroleum, {1. 1.2249, China 1. Key Laboratory for Hydrocarbon Accumulation of Education Ministry 102249 Beijing China 2. Basin & Reservoir Research center University of Petroleum 102249 Beijing China 3. PetroChina Company Limited 100011 Beijing China 4. Tarim Oilfield Company PetroChina Company Ltd. 841000 Kurle China 5. Department of Geology University of Petroleum 102249 Beijing China

The salt beds of Lower Tertiary developed in the mid-segment of Kuqa foreland fold belt, northern Tarim basin. They considerably controlled structural deformation of the belt. Ac- cording to the field observation, seismic profile interpretation and drilling data, three different structural styles of supra-salt, intra-salt and sub-salt occurred in the Kuqa foreland fold belt. Su- pra-salt structural styles mainly include thrust faults and fault-related sags. Intra-slat structural styles essentially are salt-pillows, intra-salt faults and folds, and salt weld structures. Sub-salt structural styles mainly consist of imbricated thrust faults, duplex structures, pop-up and fault-related folds. It is indicated that great differences exist among supra-salt, intra-salt and sub-salt structures of Kuqa foreland fold belt. The salt-related structures were formed in the same structural stress field. The dynamic mechanism of the salt-related structures is mainly associated with gravitation, compression and plastic flow of salt beds.

关键词： salt-related structural style, supra-salt structure, intra-salt structure, sub-salt structure, Kuga foreland fold belt.

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Experimental study on fire smoke movement in a multi-floor and multi-room building

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Science China(Technological Sciences) 2005年第3期48卷 292-304页

作者： ZHONG Maohua 1. 2 , LI Peide 2 , LIU Tiemin 1., WEI Xing 1. 2 & LIAO Guangxuan 2 1. national {1. of Safety Science and Technology, State Administration of Work Safety, beijing 1.0029, China 2. State Key Laboratory of Fire Science, University of Science and Technology of China, Hefei 23.026, China 1. national {1. of Safety Science and Technology State Administration of Work Safety 100029 Beijing China 2. State Key Laboratory of Fire Science University of Science and Technology of China 230026 Hefei China

Fire smoke movement of multi-floor and multi-room (MFMR) fire was studied at the model test building in State Key Laboratory of Fire Science (SKLFS). The ingredient, temperature, air pressure difference and air velocity of smoke were measured and analyzed. Meanwhile, the hazard of smoke ingredient to exposed occupants was analyzed based on the national standard, Occupational Exposure Limit for Hazardous Agents in the Workplace (GBZ2-2002). The experimental results showed that the maximum temperature difference in MFMR fire was located along the vertical height from the fire source. With the spreading and diffusion of smoke, the temperature of smoke layer would tend to be no difference. In the fire of woodpile and kerosene, the main smoke ingredients such as SO 2 , CO and CO 2 would first exceed human’s average physiological limit, while smoke ingredients such as NO and NO 2 would come behind. Because of the higher fluctuation range and frequency of air pressure difference of smoke in multi-layer building fire, the fire smoke would spread around everywhere of the passageway and made the human evacuation more difficult.

关键词： multi-floor and multi-room,fire experiment,smoke spread,smoke toxicity.

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Black-box testing based on colorful taint analysis

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Science China(Information Sciences) 2012年第1期55卷 171-183页

作者： CHEN Kai1.2,3.FENG DengGuo1.SU PuRui1.ZHANG YingJun1.2,3.1.tate Key Laboratory of Information Security,Institute of Software,Chinese Academy of Science,beijing 1.01.0,China 2State Key Laboratory of Information Security,Graduate University of Chinese Academy of Sciences,beijing 1.0049,China 3.2} Engineering Research {3. of Information Security,beijing 1.01.0,China 1. State Key Laboratory of Information Security Institute of Software Chinese Academy of Science Beijing 100190 China2. State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing 100049 China3. National Engineering Research Center of Information Security Beijing 100190 China

Software vulnerability detection is one of the most important methods for guaranteeing software *** main classes of methods can detect vulnerabilities in binary files:white-box testing and black-box *** former needs to construct and solve path constraints to detect *** has two main drawbacks:path exploding and complexity of *** latter often aimlessly exhausts various inputs to test binary *** paper combines both testing methods to detect vulnerabilities in binary *** analyzing the input elements that aect check condition corresponding to a certain check point,we can generate one class of inputs that get to the check point to increase fuzzing *** analyzing the relationship between guard conditions and check condition,the redundant check points are *** taint analysis method(CTAM)is proposed to compute guard conditions,which is more ecient than traditional taint analysis method(TTAM).We implemented a prototype and made several experiments on *** results showed that our method could increase the eciency of black-box testing.

关键词： software testing vulnerability detection dynamic testing black-box testing colorful taint analysis

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Study on attribute characterization for reservoir dynamic monitoring by seismic

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Science China Earth Sciences 2008年第S2期51卷 218-225页

作者： CHEN XiaoHong1.3.LI JingYe2,3.& ZHAO Wei4 1.Key Lab of Geophysical Exploration of CNPC,China Petroleum University,beijing 1.2249,China 2 Basin & Reservoir Research center,China Petroleum University,beijing 1.2249,China 3.State Key Laboratory of Petroleum Resource and Prospecting,China University of Petroleum,beijing 1.2249,China 4 Research center of CNOOC,beijing 1.0027,China 1. Key Lab of Geophysical Exploration of CNPC China Petroleum University Beijing 102249 China 3. State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China 2. Basin & Reservoir Research center China Petroleum University Beijing 102249 China 4. Research center of CNOOC Beijing 100027 China

Study on characterizing reservoir parameters dynamic variations by time-lapse seismic attributes is the theoretical basis for effectively distinguishing reservoir parameters variations and conducting time-lapse seismic interpretation,and it is also a key step for time-lapse seismic application in real oil fields. Based on the rock physical model of unconsolidated sandstone,the different effects of oil saturation and effective pressure variations on seismic P-wave and S-wave velocities are calculated and analyzed. Using numerical simulation on decoupled wave equations,the responses of seismic amplitude with different offsets to reservoir oil saturation variations are analyzed,pre-stack time-lapse seismic attributes differences for oil saturation and effective pressure variations of P-P wave and P-S converted wave are calculated,and time-lapse seismic AVO (Amplitude Versus Offset) response rules of P-P wave and P-S converted wave to effective pressure and oil saturation variations are compared. The theoretical modeling study shows that it is feasible to distinguish different reservoir parameters dynamic variations by pre-stack time-lapse seismic information,including pre-stack time-lapse seismic attributes and AVO information,which has great potential in improving time-lapse seismic interpreta-tion precision. It also shows that the time-lapse seismic response mechanism study on objective oil fields is especially important in establishing effective time-lapse seismic data process and interpreta-tion scheme.

关键词： time-lapse seismic dynamic monitoring rock physical model pre-stack attribute Amplitude Versus Offset (AVO)

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