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The control of syndepositional faulting on the Eogene sedimentary basin fills of the Dongying and Zhanhua sags, Bohai Bay Basin

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Science china Earth Sciences 2004年第9期47卷 769-782页

作者： LIN Changsong1. ZHENG Herong2. REN Jianye1. LIU Jingyan1.& Qiu Yigang1.1. {1. of Energy Geology, china University of Geosciences, Beijing 1.0083, china 2. Petroleum Exploration and Production Institute, Sino-Petroleum and chemistry Cooperation, Beijing 1.0083, china department of Energy Geology China University of Geosciences Beijing China Petroleum Exploration and Production Institute Sino-Petroleum and Chemistry Cooperation Beijing China

The Dongying and Zhanhua sags are the major hydrocarbon exploration and produc- tion subbasins in the Bohai Bay Basin. Integrated analysis of the sedimentary basin fills has shown that the syndepositional faults and their arrangement styles exerted an important influ- ence on the development and distribution of the Eogene depositional systems. The sedimentary filling evolution of the subbasins reflects the general control of the episodic rifting process. The major long-term active normal faults formed a series of paleogeomorphic accident or slopebreak zones that commonly delineated the subsidiary palaeostructural units and the depositional facies tracts and constrained the general distribution of sedimentary facies zones. The central sag boundary fault slopebreak zones usually determined the distribution of the depocenters of ter- restrial clastic depositional systems, particularly the lowstand fans or deltaic depositional sys- tems, and have proven to be the economically important targets for the exploration of subtle sandstone reservoirs. A variety of syndepositional fault arrangement patterns, including the par- allel, en echelon, combo-like, broom-like fault systems and the fault overlap or transfer zones, have been recognized in the subbasins. They generated distinctive geomorphic features and exerted a direct influence on sediment dispersal and sandbody distribution during the Eogene synrift stage. It is the key for the prediction of depositional systems tracts and reservoir sand- stones to investigate the activity and distribution of the fault slopebreak zones and reconstruct the structural paleogeomorphy in different basin filling stages of the basin evolution.

关键词： episodic rifting, fault slopebreak zone, depositional pattern, Bohai Bay Basin.

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Prediction for RNA planar pseudoknots

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Progress in Natural Science:Materials International 2007年第6期17卷 717-724页

作者： Li Hengwu1.2. Zhu Daming1. Liu Zhendong1.and Li Hong2.1. School of Computer Science and Technology, Shandong University, Jinan 2.01.0, china 2. department of Computer, Shandong Economic University, Jinan 2.001., china) School of Computer Science and Technology Shandong University Jinan 250100 China department of Computer Shandong Economic University Jinan 250014 China

Based on m-stems and semi-extensible structure, a model is presented to represent RNA planar pseudoknots, and corresponding dynamic programming algorithm is designed and implemented to predict arbitrary planar pseudoknots and simple non-planar pseudoknots with O(n4) time and O(n3) space. The algorithm folds total 2.5 sequences in the Pseudobase database, and the test results indicate that the algorithm has good accuracy, sensitivity and specificity.

关键词： algorithm RNA secondary structure pseudoknot dynamic programming.

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Microwave-assisted reaction of peptide formation by amino acid with phosphate:Exploration of the most possible channels for the origin of life

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Science china {1. 2006年第4期49卷 351-356页

作者： HU Rong1, TIAN Jinping2.& YIN Yingwu2.3 1. College of chemistry & Environment Protection Engineering, Southwest University for Nationalities, Chengdu 610041, china 2. TH-UNIS Insight Co., Ltd., Beijing 100085, china 3. Key Laboratory of Bioorganic Phosphorus chemistry & Chemical Biology, Ministry of Education, department of chemistry, tsinghua University, Beijing 1.0084, china College of chemistry & Environment Protection Engineering Southwest University for Nationalities Chengdu China TH-UNIS Insight Co. Ltd. Beijing China Key Laboratory of Bioorganic Phosphorus chemistry & Chemical Biology Ministry of Education Department of Chemistry Tsinghua University Beijing China

Microwave-assisted reaction of peptide formation by amino acids with phosphate was studied. The results showed that the products were a mixture of peptides containing dipeptide, oc- tapeptides and cyclic peptides, which could be obtained in a short time. Polyphosphate was also produced synchronously by the intermolecular condensation of phosphate. The polymerization de- gree reached 99% (pyrophosphate 64%, trimetaphosphate 35%) after 2.h at 2.0℃ under microwave irradiation. The intermediates of the mixed anhydrides formed by the intermolecular condensation of phosphates and glycin were determined by ESI-MS. Peptides were also produced by the reaction of amino acids with trimetaphosphate in aqueous solution. The conversion degree of valine reached 46.5% even at room temperature. The cyclic process of peptide formation and phosphate polymeri- zation, regeneration and utilization in amino acids-phosphate system under microwave irradiation was detected and proved. Peptides could be continually formed only by inputting energy into this system. The above recycle may be the most possible process for primitive peptide formation in the origin of life.

关键词： microwave, phosphate, amino acid, peptide, origin of life.

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A predict-correct projection method for monotone variant variational inequalities

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Chinese Science Bulletin 1998年第15期43卷 1264-1267页

作者： HAN Qiaoming 1.and HE Bingsheng 2.1. Institute of Applied Mathematics, Chinese Academy of Sciences, Beijing 1.0080,{1. 2. department of Mathematics, Nanjing University, Nanjing 2.0093,{1. Institute of Applied Mathematics Chinese Academy of Sciences Beijing China department of Mathematics Nanjing University Nanjing China

A predict_correct projection method is presented for solving monotone variant variational inequalities, which could exploit the advantages and overcome the difficulties of both explicit and implicit projection methods.

关键词： variant variational inequality explicit projection method implicit projection method predict_correct projection method.

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Ability of Agrogyron elongatum to accumulate the single metal of cadmium, copper, nickel and lead and root exudation of organic acids

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Journal of Environmental Sciences 2001年第3期13卷 368-375页

作者： YANG Hong 1. Jongathan W.C.Wong 2. YANG Zhi min\+1. ZHOU Li xiang 1.1. College of Science, Nanjing Agricultural University, Nanjing\ 2.0095, china. 2. department of Biology, Hong Kong Baptist University, china) 南京农业大学江苏南京 210095 香港浸会大学香港

Agrogyron elongatum were grown in nutrient solution containing moderate to high amounts of separate heavy metal of Cd, Cu, Ni and Ph in a greenhouse for a 9 - day. Cd, Cu, Ni and Ph generally led to decrease in the elongation of roots although the length of seedlings exposed to Cd and Ph at 0.05 and 0.5 mg/L showed to be slightly greater than that of controls. Of the four metals in the experiment, Ph was absorbed and accumulated to the highest level, with the concentrations of 92.54 mg/kg dry weight (DW) in roots and 1.683 mg/kg DW in shoots. Cd was moderately accumulated in Agrogyron elongatum, but the maximum bioaccumulation coefficients (BCs) for roots and shoots were observed. The patterns for Cu and Ni uptake and distribution in plants differed from those of Ph and Cd, as it was showed that the shoot accumulation of Cu and Ni was significantly higher than in roots. A. elongation had the highest Ni concentration in shoots (302.1.mg/kg DW) at the external concentration of 2.0 mg/L. Cu ranked second, with a shoot concentration of 1.0}30 mg/kg DW when 50 mg/L Cu in solution was applied. For the four trace elements tested, the highest concentrations in shoots decreased by the order of Ni > Cu > Ph > Cd (mg/kg DW), and those in roots were Ph > Cd > Ni > Cu (mg/kg DW). Malic, oxalic and citric acids exuded by roots exposed to 1.and 50 mg/L of the metals were detected. Release of organic acids from plants significantly differed among the metal treatments. Cu was most effectively in inducing root exudation of the three types of organic acids. Cd, and Ni were also the inducers of secretion of malic and oxalic acids. With reference of Pb, a small amounts of malic and oxalic acids were detected in the root exudates, but few quantities, of citric acid were. found. However, no correlation between alternations in root exudation of organic acids and metal accumulation could be established.

关键词： heavy metal organic acid Agrogyron elongation hyperaccumulation

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CMC surfaces in the hyperbolic 3-space

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Chinese Science Bulletin 1998年第7期43卷 547-550页

作者： YU Zuhuan 1. 2.and LI Zhenqi 1. 3 1. Institute of Mathematics, Fudan University, Shanghai 2.0433, china 2. department of Mathematics,Sichuan Union University, Chengdu 61.064, china 3. department of Mathematics, Nanchang University, Nanchang 33 nstitute of Mathemalics Fudan University Shanghai China department of Mathematics Sichuan Union University Chengdu China department of Mathematics Nanchang University Nanchang China

CMC-H surfaces satisfying H≥1.are studied. It is proved that these surfaces possess a natural representation which is a generalization of the Bryant’s result.

关键词： hyperbolic space CMC surface Weierstrass representation.

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Synthesis and Properties of the Polymeric Surfactant Based on Maleamic Acid and Styrene

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Journal of Wuhan University of Technology(Materials Science) 2011年第1期26卷 79-82页

作者：杨永清 department of Applied {1. School of Science Northwestern Polytechnical University

An alternative polymeric surfactant P（M3/St） was synthesized by solution polymerization of maleamic acid as hydrophilic monomer and styrene as hydrophobic monomer. Some factors that affect the yield and properties of the polymeric surfactant were investigated systemically. The surface tension of the polymeric surfactant reaches 37-38 mN/m. It is proved that the polymeric surfactant shows very good surface activity and emulsifying ability. The TG analysis shows that the temperature of the thermal degradation can reach 31..4 ℃. It will be used as a new type of polymeric surfactant.

关键词： maleamic acid polymeric surfactant surface activity emulsifying ability thermal resistance

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Molecular dynamics simulation of thermal stability of nanocrystalline vanadium

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Science china(Technological Sciences) 2006年第4期49卷 400-407页

作者： WEI Mingzhi1. XIAO Shifang1. YUAN Xiaojian2.& HU Wangyu1.2.1. Material Science and Engineering College, Hunan University, Changsha 41.082. china 2. department of Applied Physics, Hunan University, Changsha 41.082. china Material Science and Engineering College Hunan University Changsha China department of Applied Physics Hunan University Changsha China

The microstructure and thermal stability of nanocrystalline vanadium with an average grain size ranging from 2.86 to 7.50 nm are calculated by means of the analytic embedded-atom method and molecular dynamics. The grain boundary and nanocrystal- line grain atoms are differentiated by the common neighbor analysis method. The results indicate that the fraction of grain boundary increases with the grain size decreasing, and the mean energy of atoms is higher than that of coarse crystals. The thermal-stable tem- peratures of nanocrystalline vanadium are determined from the evolution of atomic energy, fraction of grain boundary and radial distribution function. It is shown that the stable tem- perature decreases obviously with the grain size decreasing. In addition the reasons which cause the grain growth of nanocrystalline vanadium are discussed.

关键词： nanocrystalline, embedded-atom method, molecular dynamics, thermal stability.

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Size distributions and magic number characteristics of cluster configurations formed during solidification processes of liquid metal Al

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Science china(Technological Sciences) 2006年第2期49卷 172-187页

作者： LIU Rangsu1, LIU Fengxiang1, DONG Kejun1, ZHENG Caixing1, LIU Hairong2. PENG Ping2.& LI Jiyong3 1. department of Physics, Hunan University, Changsha 410082. china 2. department of Material Science and Engineering, Hunan University, Changsha 410082. china 3. department of chemistry, Hunan University, Changsha 410082. china department of Physics Hunan University Changsha China department of Material Science and Engineering Hunan University Changsha China department of {1. Hunan University Changsha China

A molecular dynamics simulation study has been performed for a large systemconsisting of 1.0000 liquid metal Al atoms to investigate the formation and magic numbercharacteristics of the cluster configurations formed during the rapid solidification processes. Thecluster-type index method (CTIM) has been adopted to describe various types of clusterconfigurations. The results indicate that the icosahedral clusters (1.0}0 1.0}0) and theircombinations play the most important role in the rnicrostructure transitions during solidificationprocesses; for the cluster configurations of different levels formed by various combinations withdiffering numbers of basic clusters, their size distributions possess obvious magic number sequencewhich is in turn as 1.(1.), 1.(2.), 2.-2.(2.), 32.33(32., 39-40, 43-44, 48..., (those in bracket arethe corresponding value in liquid state); the magic numbers correspond to the peak value positionsof the cluster numbers for corresponding level formed with various combinations by 1. 2. 3, 4, 5, 6,7, ...basic clusters, respectively. This magic number sequence is in good agreement with theexperimental results obtained by Harris et al. At the same time, this simulation study also gives ascientific and reasonable explanation to these experimental results.

关键词： liquid metal, solidification processes, cluster configuration, magic numbers, computer simulation.

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Critical slope gradient for compulsory abandonment of farmland on the hilly Loess Plateau

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Chinese Science Bulletin 1998年第5期43卷 409-412页

作者： TANG Keli+1. ZHANG Keli 1.2.and LEI Aling 1.3 1. Institute of Soil and Water Conservation, Chinese Academy of Sciences, Yangling 71.0}00, china 2. department of Hydraulic Engineering, {2. University, Beijing 1.0084, china 3. Water Resources C Institute of Soil and Water Conservation Chinese Academy of Sciences Yangling China department of Hydraulic Engineering Tsinghua University Beijing China Water Resources Conservation Bureau of Yangtze River Ministry of Water Resources Wuhan China

Scientific evidence for the upper limit of farmland is proposed. Shallow gully erosion is one of erosion types distributed extensively on sloping farmland in the hilly regions of the Loess Plateau. Field observation and aerial photos interpretation, as well as laboratory experiments show that the shallow gully erosion occurring on the steeper farmland in the hilly regions of the Loess Plateau is an important factor leading to intensive erosion on slope, because of its extensive distribution and intensive runoff collection. The data on the formation, development and distribution of shallow gullies on sloping farmland indicate that critical slope gradient for shallow gully initiation ranges from 1. to 2. degrees with an average of 1..2.degrees. Therefore, it is suggested that critical slope gradient for compulsory abandonment of farmland on the hilly Loess Plateau should be kept within the critical slope gradient for shallow gully initiation to prevent shallow gully formation in order to control soil loss more effectively. But as the first step, the cultivation on the slopes with slope larger than 2. degrees where the maximum erosion occurs should be strictly forbidden.

关键词： hilly region of Loess Plateau upper limitation for farmland shallow gully erosion erosion dynamic.

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