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Mechanism for calcite dissolution and its contribution to development of reservoir porosity and permeability 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 Department 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 Department 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 porosity and permeability of gas-bearing sandstone reservoirs in the Kela 2 gas field of the Tarim Basin, Northwestern China. Sandstone samples and pore water samples are col-lected from well KL201 in the Tarim Basin. Vertical profiles of porosity, permeability, pore 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. Porosity and permeability values are in-versely correlated with the calcite abundance, indicating that calcite dissolution and precipitation may be controlling porosity and permeability of the reservoir rocks. Pore 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, temperature, pressure, Ca2+ concen-tration, the total inorganic carbon concentration (ΣCO2), and the type of pore water. Thermodynamic phase equilibrium and mass conservation laws are applied to calculate the calcite saturation state as a function of a few key parameters. The model calculation illustrates that the calcite solubility is strongly dependent on the chemical composition of pore 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, pore 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 pore water is supersaturated with respect to calcite. Massive calcite precipitation was observed at this depth interval and

关键词： calcite dissolution porosity thermodynamic Tarim Basin

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Global analysis on slope stability and its engineering application

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Science China(Technological Sciences) 2009年第2期52卷 507-512页

作者： ZHENG Hong1,2 & ZHOU ChuangBing3 1 state key laboratory of Geomechanics and Geotechnical Engineering, Wuhan 430071, China 2 China Three Gorges University, key laboratory of Geological Hazards on Three Gorges Reservoir Area, Ministry of Education, Yi Chang 443002, China 3 School of Civil Engineering, Wuhan University, Wuhan 430072, China 1. state key laboratory of Geomechanics and Geotechnical Engineering Wuhan 430071 China 2. China Three Gorges University Key Laboratory of Geological Hazards on Three Gorges Reservoir Area Ministry of Education Yi Chang 443002 China 3. School of Civil Engineering Wuhan University Wuhan 430072 China

In hydraulic engineering, sometimes it is necessary to consider the stability of sliding bodies with lateral frictional boundaries. Neither the existing three dimensional limit equilibrium methods nor the commercial software products are able to treat such situations. The three dimensional factor of safety is accordingly underestimated; while the shearing strength based on the three dimensional back analysis is overestimated. In this study, the lateral boundaries are regarded as the part of the slip surface. Based on the expression of the normal pressure on the slip surface and the patch interpolation, a rigorous solution for the three dimensional limit equilibrium analysis is realized. Meanwhile, the proposed procedure is applied to the stability analysis of the slope with a cable platform on the right bank in Da Gang Shan hydraulic project under construction.

关键词： slope stability the limit equilibrium methods three dimensional problems

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WAVE-CURRENT INTERACTIONS WITH THREE-DIMENSIONAL FLOATING BODIES

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Journal of Hydrodynamics 2010年第2期22卷 229-240页

作者： LIU Zhen TENG Bin NING De-zhi GOU Ying state key laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024China state key laboratory of Satellite Ocean Environment Dyamics Hangzhou 310012 China

A Time-domain Higher-Order Boundary Element Method（THOBEM） is developed for simulating wave-current interactions with 3-D floating *** a Taylor series expansion and a perturbation procedure,the model is formulated to the first-order in the wave steepness and in the current velocity,*** boundary value problem is decomposed into a steady double-body flow problem and an unsteady wave ***-order boundary integral equation methods are then used to solve the proposed problems with a fourth-order Runge-Kutta method for the time *** artificial damping layer is adopted to dissipate the scattering *** from the other time-domain numerical models,which are often focused on the wave-current interaction with restrained bodies,the present model deals with a floating *** numerical results of wave forces,wave run-up and body response are all in a close agreement with those obtained by frequency-domain *** proposed numerical model is further applied to investigate wave-current interactions with a floating body of complicated *** this work,the regular and focused wave combined with current interacting with a truss-spar platform is investigated.

关键词： wave-current interaction floating bodies time-domain simulation Time-domain Higher-Order Boundary Element Method(THOBEM)

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Cycladophora davisiana(Radiolarian)in the Bering Sea during the late Quaternary:A stratigraphic tool and proxy of the glacial Subarctic Pacific Intermediate Water

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Science China Earth Sciences 2005年第10期48卷 1698-1707页

作者： WANG Rujian1 & CHEN Ronghua2 1. state key laboratory of Marine Geology, Tongji University, Shanghai 200092, China 2. The key laboratory of Submarine Geoscience, state Oceanic Administration, Hangzhou 310012, China state key laboratory of Marine Geology Tongji University Shanghai China The key laboratory of Submarine Geoscience state Oceanic Administration Hangzhou China

Cycladophora davisiana (Radiolarian) contents are counted in two cores of the Ber-ing Sea and correlated well with the oxygen isotopic records of ice in the deep core obtained by the Greenland Ice Sheet Project II (GISP 2) and deep-sea sediments (SPECMAP) of the world oceans. Millennial scale climatic events, for example, Younge Dryas and B?lling/Aller?d events, Heinrich1 and Dansgaard-Oeschger1events, recorded by C. davisiana percents are distin-guished from Core B4-2. C. davisiana events b, c1, c2, d, e1 and e2, respectively, corresponding to oxygen isotopic 2.0, 3.1, 3.3, 4.0, 5.1 and 5.3, are identified from Core B2-9. High resolution re-cords of C. davisian are tuned to the oxygen isotopic records in GISP 2 and SPECMAP and the depth-age frameworks are established in the two cores, supplying a stratigraphic base for future paleoceanographic and paleoclimatic studies. High C. davisiana during the glacial periods in the two cores indicate that they can serve as a proxy of the glacial Subarctic Pacific Intermediate Water, which verifies the glacial Subarctic Pacific Intermediate Water brought from the Bering Sea.

关键词： Cycladophora davisiana, stratigraphic tool, YD and B/A events, Heinrich 1 and D/O1 events, proxy of glacial Subarctic Pacific Intermediate Water, late Quaternary, Bering Sea.

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Cure of experimental botulism and antibotulismic effect of toosendanin

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Acta Pharmacologica Sinica 2004年第6期25卷 137-146页

作者： Yu-liang SHI2, Zhong-feng WANG key laboratory of neurobiology, Shanghai Institutes for Biological Sciences, Chinese Academy ofScience, Shanghai200031, China key laboratory of neurobiology Shanghai Institutes for Biological Sciences Chinese Academy of Science Shanghai 200031 Chin

Botulinum neurotoxins (BoNTs), a group of bacterial proteins that comprise a light chain disulfide linked a heavy chain, are the most lethal biotoxins known to mankind. By inhibiting neurotransmitter release, BoNTs cause severe neuroparalytic disease, botulism. A series of important findings in the past 10 years which displayed the molecular targets of BoNTs and hence proposed a four-step action mechanism to explain BoNT intoxication greatly advanced the study of antibotulismic drug. In this article, we reviewed these progresses and anti-botulismic compounds found in recent years. These compounds function due to their facilitation on neurotransmitter release or to their interference on the binding, internalization, translocation, and endopeptidase activity of the toxins. Toosendanin is a triterpenoid derivative extracted from a digestive tract-parasiticide in Chinese traditional medicine. Chinese scientists have found that the compound is a selective prejunctional blocker. In spite of sharing some similar action with BoNT, toosendanin can protect botulism animals that have been administrated with lethal doses of BoNT/A or BoNT/B for several hours from death and make them restore normal activity. The neuromuscular junction preparations isolated from the rats that have been injected with toosendanin tolerate BoNT/A challenge. Toosendanin seems to have no effect on endopeptidase activity of BoNT, but blocks the toxin approach to its enzymatic substrate.

关键词： toosendanin botulinum toxins botulism synaptic transmission neurotransmitter triterpene Chinese traditional medicine

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AN ITERATIVE PROCEDURE FOR DOMAIN DECOMPOSITION METHOD OF SECOND ORDER ELLIPTIC PROBLEM WITH MIXED BOUNDARY CONDITIONS

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Journal of Computational Mathematics 1997年第4期15卷 319-326页

作者： Lie-heng Wang (state key laboratory of Scientific and Engineering Computing, ICMSEC, Chinese Academy of Sciences, Beijing, China) 中科院计算数学与科学工程计算所科学与工程计算国家重点实验室北京

This paper is devoted to study of an iterative procedure for domain decomposition method of second order elliptic problem with mixed boundary conditions (i.e., Dirichlet condition on a part of boundary and Neumann condition on the another part of boundary). For the pure Dirichlet problem, Marini and Quarteroni [3], [4] considered a similar approach, which is extended to more complex problem in this paper.

关键词： EH Math AN ITERATIVE PROCEDURE FOR DOMAIN DECOMPOSITION METHOD OF SECOND ORDER ELLIPTIC PROBLEM WITH MIXED BOUNDARY CONDITIONS

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The synthesis, bioactivity and paramagnetic resonance of angiotensin Ⅱ and its spin labelled derivative

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Chinese Science Bulletin 1997年第21期42卷 1843-1846页

作者： WANG Rui, LI Xiaoxu, HU Xiaoyu, NI Jingman, LI Changling and LU Jingfen1. Department of Biology, state key laboratory of Applied Organic Chemistry, Lanzhou 730000, China 2. Department of Chemistry, Lanzhou University, Lanzhou 730000 3. state key laboratory of Natural and Biomimetic Drugs, Beijing medical U-niversity, Beijing 100083, China. Department of Biology State Key Laboratory of Applied Organic Chemistry Lanzhou China Department of Chemistry Lanzhou University Lanzhou state key laboratory of Natural and Biomimetic Drugs Beijing Medical University Beijing China

ANGIOTENSIN Ⅱ(Ang Ⅱ) is an important constituent in renin-angiotension system (RAS).The amino acid sequence of Ang Ⅱ is DRVYIHPF. Ang Ⅱ plays an important role both inmaintenance of normal blood pressure and in occurrence of hypertension. Ang Ⅱ binding re-ceptor can induce many kinds of physiological effects. Spin labeling is an effective method thatgreatly deepened the knowledge in structure, movement and interaction of biologicalmolecules. For example, it has been used in studying interaction of antigen and antibody suc-

关键词： spin labelled angiotensin Ⅱ solid phase peptide synthesis bioactivity electron spin resonance.

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Integrated modeling of nitrogen oxides formation in diesel engines

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Progress in Natural Science:Materials International 2007年第12期17卷 1476-1481页

作者： Song Jinou, Yao Chunde and Wang Hongfu(state key laboratory of Engine, Tianjin University, Tianjin 300072, China) state key laboratory of Engine Tianjin University Tianjin 300072 China

To account for the effects of both chemistry and flow turbulence, the present study proposes an integrated NO sub-model that combines the extended Zel’dovich mechanism and engine CFD computations to simulate the NO histories in a diesel engine. NOx sub-model parameters and pollutant formation mechanisms can be more easily investigated by solving the NOx sub-model. The new NO formation model incorporating the effects of both chemical kinetics and turbulent mixing was applied to simulate a diesel engine with a quiescent combustion chamber, and one with a re-entrant combustion chamber; the premise of the model being the reaction rate is mainly determined by a kinetic timescale and a turbulent timescale. The results indicate that the predicted NO formulation from the new model agrees well with the measured data. As the utilization of fossil fuels continues to increase, the control of NOx emissions is a worldwide concern; and it is imperative to understand fully the NOx reaction processes in combustion systems. This technology has the potential to enhance the application of various combustion techniques used to reduce NOx emissions from practical combustion systems.

关键词： nitrogen oxides (NOx) combustion turbulence diesel.

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Recent studies on chemistry of novel μ-CO-containing butterfly Fe/E (E=S,Se,Te) cluster salts

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Science China Chemistry 2009年第1期52卷 1-14页

作者： SONG LiCheng Department of Chemistry, state key laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, China 1. Department of Chemistry State Key Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071 China

This article describes recent developments in chemical study on a series of butterfly-shaped μ-CO-containing Fe/E (E = S, Se, Te) cluster salts. These salts include eleven novel cluster anions, which are the single butterfly one μ-CO-containing [(μ-RE)(μ-CO)Fe2(CO)6]- (A), the double butterfly two μ-CO-containing {[(μ-CO)Fe2(CO)6]2(μ-EZE-μ)}2- (B, E = S; C, E = Se), the triple butterfly three μ-CO- containing {[(μ-CO)Fe2(CO)6]3[(μ-SCH2CH2)3N]}3- (D), {[(μ-CO)Fe2(CO)6]3[1,3,5-(μ-SCH2)3C6H3]}3- (E), {[(μ- CO)Fe2(CO)6]3[(μ-SCH2)3CMe]}3- (F), the double butterfly one μ-CO-containing {[(μ-CO)Fe2(CO)6] [Fe2(CO)6][(μ-SCH2)3CMe]} - (G) derived in situ from F, the quadruple butterfly four μ-CO-containing {[(μ- CO)Fe2(CO)6]4[1,2,4,5-(μ-SCH2)4C6H2]}4- (H), the triple butterfly two μ-CO-containing {[(μ-CO)Fe2(CO)6]2 [Fe2(CO)6][1,2,4,5-(μ-SCH2)4C6H2]}2- (I) derived in situ from H, the quadruple butterfly four μ-CO-con- taining {[(μ-CO)Fe2(CO)6]4[(μ-SCH2)4C]}4- (J), and the triple butterfly two μ-CO-containing {[(μ-CO)Fe2 (CO)6]2[Fe2(CO)6][(μ-SCH2)4C]}2- (K) derived in situ from J. This article describes not only the synthetic methods for formation of such anionic cluster (A-K) salts, but also their novel reactions leading to various new types of butterfly Fe/E cluster complexes. All these findings described in this article are important both theoretically and practically.

关键词： butterfly cluster synthesis structure reaction mechanism

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METHODS OF MODERN DESIGN FOR CYLINDRICAL GEAR DRIVE BASED ON THE INTERNET

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Chinese Journal of Mechanical Engineering 2002年第1期15卷 62-65页

作者： Lin Chao Li Runfang state key laboratory of Mechanical Transmission，Chongqing University， Chongqing 400044，China state key laboratory of Mechanical Transmission Chongqing University Chongqing 400044 China

The basic principle of modern design of cylindrical gear drive based on theInternet is described. The methods of optimized design, finite element analysis, CAD design and webdesign as well as research and development entity of three parties such as institute research unit(or university), enterprise and customer are also studied. Its purpose is to provide a necessaryfoundation for realizing the design of cylindrical gear drive from different location on the modemInternet and to explore a practice application route.

关键词： Internet Cylindrical gear Mechanical model

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