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Main Controls on Hydrocarbon Accumulation in the Paleozoic in Central Saudi Arabia

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Petroleum Science 2007年第2期4卷 10-17页

作者： Bai Guoping (Key Laboratory for Hydrocarbon Accumulation under ministry of education, china University of Petroleum, Beijing 102249, china) china Univ Petr Key Lab Hydrocarbon Accumulat Minist Educ Beijing 102249 Peoples R China

Sandi Arabia is renown for its rich oil and gas Mesozoic. However, the discovery of Paleozoic fields in resources with the bulk of the reserves reservo/red in the the late 1980s has encouraged further exploration in the Paleozoic. This paper reviews the salient features of the Paleozoic petroleum geology in central Saudi Arabia and discusses the main factors controlling hydrocarbon accumulation in the Paleozoic. The Lower Silurian Qusaiba hot shale is the principal source rock for the hydrocarbons discovered in the Ordovician to Permian reservoirs. Of them, the Permo- Carboniferous Unayzah and Upper Ordovician Sarah Formations have the best exploration potential. The key factors controlling hydrocarbon accumulation in the Unayzah Formation are migration pathways and reservoir petrophysics. The key factors controlling hydrocarbon accumulation in the Sarah Formation are reservoir petrophysics and the development of structural traps.

关键词： Paleozoic oil and gas accumulations central Saudi Arabia main controls Qusaiba hot shale Unayzah play,Sarah play

MULTISCALE MECHANICAL BEHAVIORS IN DISCRETE MATERIALS: A REVIEW

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Acta Mechanica Solida Sinica 2010年第6期23卷 579-591页

作者： Xiaojing Zheng Dengming Wang (Key Laboratory of Mechanics on Western Disaster and Environment,the ministry of education of china,Lanzhou University,Lanzhou 730000,china) Key Laboratory of Mechanics on Western Disaster and Environment the Ministry of Education of China Lanzhou University Lanzhou China

The discrete material, which belongs to the category of soft materials, is one of the most prevalent forms of matter in nature and engineering fields. These materials often exhibit abundant and complex mechanical properties which are still far from being perfectly understood. From the view of multi-scale framework concentrated on the ＇bridge＇ role in the macro-micro relation, this review mainly introduces some theoretical investigations of mechanical behaviors in discrete materials, including the continuum constitutive model based on the macroscopic phenomenological approach and coupled micro-macro approach, the statistical analysis of some microscopic physical quantities involved contacted forces between particles and its transmission within the whole system, and the statistical analysis for some microscopic processes in aeolian landform systems involving the grain-bed impact, the transportation and sedimentation of wind-blown sand flux, et al. Finally, some further worthwhile challenges in these fields are suggested.

关键词： discrete material multiple space and time scales trans-scales correlation sanddune statistical analysis

Method of Green’s function of nonlinear vibration of corrugated shallow shells

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Science china(Physics,Mechanics & Astronomy) 2008年第6期51卷 678-686页

作者： YUAN Hong Key Laboratory of Disaster Forecast and Control in Engineering, ministry of education of china, Institute of Applied Mechanics, Jinan University, Guangzhou 510632, china Key Laboratory of Disaster Forecast and Control in Engineering Ministry of Education of China Institute of Applied Mechanics Jinan University Guangzhou China

Based on the dynamic equations of nonlinear large deflection of axisymmetric shallow shells of revolution, the nonlinear free vibration and forced vibration of a corrugated shallow shell under concentrated load acting at the center have been investigated. The nonlinear partial differential equations of shallow shell were re-duced to the nonlinear integral-differential equations by using the method of Green’s function. To solve the integral-differential equations, the expansion method was used to obtain Green’s function. Then the integral-differential equations were reduced to the form with a degenerate core by expanding Green’s function as a series of characteristic function. Therefore, the integral-differential equations be-came nonlinear ordinary differential equations with regard to time. The ampli-tude-frequency relation, with respect to the natural frequency of the lowest order and the amplitude-frequency response under harmonic force, were obtained by considering single mode vibration. As a numerical example, nonlinear free and forced vibration phenomena of shallow spherical shells with sinusoidal corrugation were studied. The obtained solutions are available for reference to the design of corrugated shells.

关键词： corrugated shells spherical shells Green’s function integral equation nonlinear vibration

Chloride transference during electrochemical chloride extraction process

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Science china(Technological Sciences) 2010年第6期53卷 1466-1470页

作者： YAO Wu & ZHAO Zheng Key Laboratory of Advanced Civil Engineering Materials (Tongji University),ministry of education of china,Shanghai 200092,china Key Laboratory of Advanced Civil Engineering Materials (Tongji University) Ministry of Education of China Shanghai China

Chemical titration method and lab-made chloride probes were jointly adopted to investigate the effects of water-to-cement (W/C) ratio and the impressed current density on chloride transport for cement-based materials during electrochemical chloride extraction (ECE) *** dissolution of bound chlorides and the effect of current density on dissolution were *** variations of chloride concentration at different depths and the chloride transference process were *** results show that W/C ratios adopted have slight influence on chloride extraction,while chloride extraction efficiency is mainly determined by the impressed current *** ECE process a portion of bound chloride ions dissolved and the amount of bound chlorides released is directly proportional to current density.

关键词： electrochemical chloride extraction transference bound chloride current density

Tuning surface active oxygen of lanthanum oxide via partial dissolution and regrowth of crystallites

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Journal of Natural Gas Chemistry 2011年第5期20卷 483-486页

作者： Zhiming Gao, Huili Li Key Laboratory of Cluster Science, ministry of education of china Department of Chemistry, School of Science, Beijing Institute of Technology, Beijing 100081, china Key Laboratory of Cluster Science Ministry of Education of China Department of Chemistry School of Science Beijing Institute of Technology Beijing 100081 China

A commercial lanthanum oxide was modified into X%-La2O3 samples via partial dissolution and regrowth of crystallites, wherein the X value denotes the weight percent of the initial metal oxide powder dissolved by nitric acid. BET measurements and TEM observations indicate that the 20%-La2O3 sample has an increased specific surface area, relatively thin and small crystallites in size. TPD/TPR profiles also show that the 20%-La2O3 sample has more surface active oxygen than the 0%-La2O3 sample. Among the four X%-La2O3 samples, the highest activity for methane oxidation was obtained over the 20%-La2O3 sample. Therefore, the present work proves that the method of partial dissolution and regrowth of crystallites are effective to modify surface property of lanthanum oxide.

关键词： solid state reaction surface oxygen crystallite regrowth TPR metal oxide

Performance analysis and optimal design for well patterns in anisotropic formations

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Petroleum Science 2008年第3期5卷 251-257页

作者： Liu Yuetian Key Laboratory of Petroleum Engineering Ministry of Education China University of Petroleum Beijing 102249 China

The mechanism of the effects of anisotropic permeability on well patterns and reservoir development are investigated by coordinate transformation, fluid flow analysis, and reservoir development concepts. Anisotropy of permeability has reconstructive effects on well patterns. The originally designed flooding units are broken up, and new pattern units are made up of the wells that belong to different original units. The behavior possesses strong randomness, and leads to a complicated relationship among the injection and production wells, and unpredictable productivity of the formations. To prevent the break-up of well patterns, well lines should be either parallel or perpendicular to the maximum principal direction of the anisotropic permeability （i.e. the fracture direction）. To optimize the development effects ofanisotropic formations, the latitudinal and longitudinal well spacing of the well network are calculated from the principal values of the anisotropic permeability.

关键词： Fractured reservoir anisotropic permeability performance analysis well pattern design

Probing the hydration of composite cement pastes containing fly ash and silica fume by proton NMR spin-lattice relaxation

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Science china(Technological Sciences) 2010年第6期53卷 1471-1476页

作者： SHE AnMing & YAO Wu Key Laboratory of Advanced Civil Engineering Materials (Tongji University),ministry of education,Shanghai 200092,china Key Laboratory of Advanced Civil Engineering Materials (Tongji University) Ministry of Education Shanghai China

Proton NMR spin-lattice relaxation (T1) was used as a prober for observing the hydration process of composite cement pastes blending fly ash and silica fume during the early *** distribution at initial time,evolution curves and signals intensity of T1 were shown in this *** demonstrate that the T1 distribution curves at initial time exhibit two peaks,which are regarded as two different water phases in the *** evolution curves of T1 are in good agreement with the hydration process of composite pastes and could be roughly divided into four stages:initial period,dormant period,acceleration period and steady *** hydration mechanism for each stage was *** hydration of the composite cement pastes was retarded by the addition of fly ash and silica fume when compared to that of pure ***,the hydration degree of the cement in the blends was promoted.

关键词： NMR relaxation cement fly ash silica fume hydration

L^2-Algebraic Decay Rate for Transient Birth-Death Processes

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Chinese Annals of Mathematics,Series B 2012年第4期33卷 583-594页

作者： Lijuan CHENG1 Yingzhe WANG2 1Laboratory of Mathematics and Complex Systems, the ministry of education of china School of Mathe-matical Sciences, Beijing Normal University, Beijing 100875, china. 2Laboratory of Mathematics and Complex Systems, the ministry of education of china School of Mathematical Sciences, Beijing Normal University, Beijing 100875, china. Laboratory of Mathematics and Complex Systems the Ministry of Education of China School of Mathematical Sciences Beijing Normal University Beijing China

This paper is a continuation of the study of the algebraic speed for Markov processes. The authors concentrate on algebraic decay rate for the transient birth-death processes. According to the classification of the boundaries, a series of the sufficient conditions for algebraic decay is presented. To illustrate the power of the results, some examples are included.

关键词： Transient Birth-death processes Algebraic decay

Preparation of nanoparticles with an environment-friendly approach

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Journal of Environmental Sciences 2009年第6期21卷 727-730页

作者： YAO Kefu,PENG Zhen,FAN Xiaolin Key Laboratory of Advanced Materials Processing Technology,ministry of education of china,Department of Mechanical Engineering,Tsinghua University,Beijing 100084,china. Key Laboratory of Advanced Materials Processing Technology Ministry of Education of China Department of Mechanical Engineering Tsinghua University Beijing 100084 China

Developing various approaches for preparing high performance materials has long been topics and tasks both for scientists and for engineers. Despite that many methods have been developed for preparing nanomaterials, developing simple and environment-friendly ways for preparing nanomaterials is very attractive. Here a simple approach of synthesizing Fe3O4 nanoparticles by arc-discharge submerging in water was reported. The results showed that by this method Fe3O4 nanoparticles can be synthesized at large scale. The as-prepared Fe3O4 nanoparticles exhibited uniform spherical shape and their diameters varied with arc-discharging parameters. The experimental results showed that the size of the synthesized Fe3O4 nanoparticles can be controlled through adjusting the processing parameters. Since no vacuum system has been used, the synthesizing process is greatly simplified. In addition, only cheap deionized water and industrial iron bar are used and no pollution or harmful byproducts are found in the synthesis process. It indicated that the present approach is a simple, low-cost and environment-friendly one for preparing nanoparticles.

关键词： nanoparticles preparation approach Fe3O4