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Science china(Physics,Mechanics & Astronomy) 2010年第8期53卷 1475-1480页

作者： liu chengshi department of mathematics, northeast petroleum university, daqing 163318, china 1. department of mathematics Northeast Petroleum University Daqing 163318 China

We give an equivalent construction of the infinitesimal time translation operator for partial differential evolution equation in the algebraic dynamics algorithm proposed by Shun-Jin Wang and his students. Our construction involves only simple partial differentials and avoids the derivative terms of δ function which appear in the course of computation by means of Wang-Zhang operator. We prove Wang’s equivalent theorem which says that our construction and Wang-Zhang’s are equivalent. We use our construction to deal with several typical equations such as nonlinear advection equation, Burgers equation, nonlinear Schrodinger equation, KdV equation and sine-Gordon equation, and obtain at least second order approximate solutions to them. These equations include the cases of real and complex field variables and the cases of the first and the second order time derivatives.

关键词： algebraic dynamics infinitesimal time translation operator partial differential evolution equation

Effect of current pulses on fracture morphology in superplastic deformation of 2091 Al Li alloy

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中国有色金属学会会刊：英文版 1999年第3期9卷 514-518页

作者： liu Zhiyi(刘志义) Mechanical department, university of petroleum, Dongying 257062, P. R. china Univ Petr Dept Mech Dongying 257062 Peoples R China

The effect of current pulses on the fracture morphology in the superplastic deformation of 2091 Al Li alloy at two kinds of initial strain rate ( 1=3.33×10 -3 s -1 ; 2=3.33×10 -2 s -1 ) was *** results show that current pulse turns fracture of superplastic deformation at low strain rate from local interior fracture morphology to typical fracture by growth and interlinkage of cavities, and at high strain rate from rough grain boundary surface to smooth grain boundary surface. It is indicated that the characteristic, that current pulse promotes atomic diffusion, maintains an equiaxial grain microstructure at low strain rate, and accelerates the development of diffusional type of cavity and relaxes stress concentration at triple junction of grain boundaries at high strain rate, and makes the superplastic deformation at two kinds of strain rate show a normal superplastic fracture morphology.

关键词： Al Li alloy superplastic deformation fracture morphologyDocument code: A

ABNORMAL BENDING OF MICRO-CANTILEVER PLATE INDUCECD BY A DROPLET

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Acta Mechanica Solida Sinica 2010年第5期23卷 428-436页

作者： Jianlin liu Xueyan Zhu Xinkang Li Zhiwei Li 1(department of Engineering Mechanics,china university of petroleum,Qingdao 266555,china) [a] department of Engineering Mechanics China University of Petroleum Qingdao 266555 China

The abnormal bending of a micro-cantilever plate induced by a droplet is of great interest and of significance in micro/nano-manipulations. In this study, the physical mechanism of this abnormal phenomenon induced by an actual droplet is elucidated. Firstly, the morphologies of 2D and 3D droplets axe solved analytically or numerically. Then the Laplace pressure difference acting on the cantilever plate caused by the droplet is presented. Finally, the deflections of the micro-cantilever plates driven by the capillary forces are quantitatively analyzed. These analytical results may be beneficial to some engineering applications, such as micro-sensors, MEMS and the micro/nano-measurement.

关键词： micro-cantilever plate surface tension Laplace pressure difference abnormal bending deflection

Identification Algorithm Based on the Approximate Least Absolute Deviation Criteria

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International Journal of Automation and computing 2012年第5期9卷 501-505页

作者： Bao-Chang Xu Xin-Le liu department of Automation, china university of petroleum, Beijing 102249, china 1. department of Automation China University of Petroleum Beijing 102249 China

Considering the situation that the least-squares (LS) method for system identification has poor robustness and the least absolute deviation (LAD) algorithm is hard to construct, an approximate least absolute deviation (ALAD) algorithm is proposed in this paper. The objective function of ALAD is constructed by introducing a deterministic function to approximate the absolute value function. Based on the function, the recursive equations for parameter identification are derived using Gauss-Newton iterative algorithm without any simplification. This algorithm has advantages of simple calculation and easy implementation, and it has second order convergence speed. Compared with the LS method, the new algorithm has better robustness when disorder and peak noises exist in the measured data. Simulation results show the efficiency of the proposed method.

关键词： System identification least absolute deviation (LAD) Gauss-Newton algorithm robustness disorder and peak noise

Origin and controlling factors of chlorite coatings—an example from the reservoir of T_3x Group of the Baojie area,Sichuan Basin,china

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petroleum Science 2009年第4期6卷 376-382页

作者： Peng Jun1,liu Jinku2,Wang Yan2 and liu Jianfeng2 1 Scientific Research department,Southwest petroleum university,Chengdu,Sichuan 610500,china 2 Graduate School,Southwest petroleum university,Chengdu,Sichuan 610500,china Scientific Research department Southwest Petroleum University Chengdu Sichuan China Graduate School Southwest Petroleum University Chengdu Sichuan China

The study of the chlorite coatings always attracts scholars in china and other countries because the chlorite coatings play an important role in the preservation of residual primary pores in sandstone *** present,the study of the origin and the controlling factors is relatively *** occurrence,time of formation,genesis,controlling factors,and the mechanism of chlorite coatings inhibiting quartz overgrowths were studied in detail with thin section and SEM *** were from the sandstone reservoirs of the T3x Group in the Baojie area,the transitional zone from the middle to the south of Sichuan *** results indicate that the chlorite coatings on the walls of the pore spaces are oriented perpendicular to grain surfaces in the form of isopachous(even-thickness) grain-coating,while the chlorite coatings at the contacts between adjacent detrital grains are arranged with a preferred orientation tangential to the surface of detrital *** chlorite coatings were formed in the eogenetic *** were formed by recrystallization of Fe-rich clay films during the syndepositional period,and chlorite cements would be recrystallized after the coatings’ *** formation of chlorite coatings was mainly controlled by the depositional environment,provenance conditions,and diagenetic *** presence of chlorite coatings could result in the preservation of primary pores in deeply buried sandstone reservoirs by effectively inhibiting quartz overgrowths and the development of compaction and pressure solution.

关键词： Chlorite coatings occurrence time of formation origin controlling factor quartz overgrowths T3x Group

Comprehensive evaluation of mechanism of "chimney effect" using principles of magnetism, geochemistry and mineralogy

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Chinese Science Bulletin 1998年第9期43卷 743-748页

作者： liu Qingsheng 1, CHENG Tongjin 2 and liu Shugen 3 1. department of Applied Geophysics, china university of Geosciences, Wuhan 430074, china 2. Center of petroleum Geochemistry, china National Star petroleum Corporation, Hefei 230022, china 3. The St department of Applied Geophysics China University of Geosciences Wuhan China Center of petroleum Geochemistry China National Star Petroleum Corporation Hefei China The State Key Laboratory of Oil/Gas Reservoir Geology and Exploitation of china Chengdu Institute of Technology Chengdu China

Study of forming mechanism of "chimney-effect" (CE) has important significance for basic theory and applications of non-seismic geophysical and geochemical methods locating oil/gas reservoirs. The theoretical basis of comprehensive evaluation of mechanism of CE using principles of magnetism, geochemistry and mineralogy has been reviewed, with the problems to be solved: (ⅰ) study for the relationship between process of oil/gas migration and geochemical field; (ⅱ) analysis of genesis of magnetic, geochemical and mineralogical anomaly; (ⅲ) interpretation of surface soil magnetism and geochemical anomaly combined with seismic data.

关键词： chimney effect (CE) hydrocarbon microseepage oil/gas accumulation.

Intramolecular carbon isotope of propane from coal-derived gas reservoirs of sedimentary basins:Implications for source,generation and post-generation of hydrocarbons

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Geoscience Frontiers 2024年第4期15卷 230-244页

作者： Xiaofeng Wang Peng liu Wenhui liu Changjie liu Ying Lin Dongdong Zhang State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi’an 710069China College of Safety Science and Engineering Xi’an University of Science and TechnologyXi’an 710054China State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development Petroleum Exploration and Production Research InstituteSINOPECBeijing 100083China Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhou 730000China department of Earth and Planetary Sciences University of CaliforniaRiversideRiversideCA 92521USA

An intramolecular isotopic study was conducted on natural gases collected from coal-derived gas reser-voirs in sedimentary basins of china to determine their position-specific isotope *** propane from the Turpan-Hami Basin exhibited negativeΔc-T(δ13Ccentral-δ13Cterminal)values ranging from-3.9‰to-0.3‰,with an average of-2.1‰.Propane from the Ordos Basin,Sichuan Basin,and Tarim Basin showed positiveΔC-T values,with averages of 1.3‰,5.4‰and 7.6‰,*** carbon isotope compositions reveal the precursors and the propane generation pathways in the petroliferous *** formed from the thermal cracking of TypeⅢkerogen has largerδ13Ccentral andδ13Cterminal values than propane from TypeⅠ/Ⅱ*** precursor for natural gases collected in this study is identified to be TypeⅢ*** our data to calculated results for thermal cracking of TypeⅢkerogen,we found that propane from the low-maturity gas reservoir in the Turpan Basin was generated via the i-propyl radical pathway,whereas propane from the Sulige tight gas reservoir in the Ordos Basin was formed via the n-propyl radical pathway.δ13Cterminal values covered a narrow range across basins,in contrast toδ*** terminal carbon position in propane is less impacted by microbial oxidation and more relevant to maturity levels and ***,δ13Cterminal has a good potential to infer the origin and maturity level of natural *** examining post-generation processes,we proposed an improved identification strategy for microbial oxidation of natural gases,based on the position-specific carbon isotope distributions of *** from the Liaohe Depression of the Bohai Bay Basin and the Sichuan Basin were detected of post-generation microbial ***,position-specific carbon isotope composition of propane provides new insights into the generation mechanism and post-generation processes of natural gas in the geological period at the atomic level.

关键词： Intramolecular isotope Position-specific isotope Kinetic isotope effects Microbial anaerobic oxidation

Geophysical methods for the study of sedimentary cycles

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petroleum Science 2009年第3期6卷 259-265页

作者： Xu Jingling liu Luofu Wang Guiwen Shen Jinsong Zhang Chunhua School of Resources and Information Technology China University of Petroleum Beijing 102249 China State Key Laboratory of petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China department of Computer Science and Technology China University of Petroleum Beijing 102249 China

We present the wavelet depth-frequency analysis and variable-scale frequency cycle analysis methods to study sedimentary cycles. The spectrum analysis, variable-scale frequency cycle analysis, and wavelet depth-frequency analysis methods are mainly discussed to distinguish sedimentary cycles of different levels. The spectrum analysis method established the relationship between the spectrum characteristics and the thickness and number of sedimentary cycles. Both the variable-scale frequency cycle analysis and the wavelet depth-frequency analysis are based on the wavelet transform. The variable-scale frequency cycle analysis is used to obtain the relationship between the periodic changes of frequency in different scales and sedimentary cycles, and the wavelet depth-frequency analysis is used to obtain the relationship between migration changes of frequency energy clusters and sedimentary cycles. We designed a soft-ware system to process actual logging data from the Changqing Oilfield to analyze the sedimentary cycles, which verified the effectiveness of the three methods, and good results were obtained.

关键词： Sedimentary cycles spectrum analysis wavelet depth-frequency analysis variable-scale frequency cycle analysis

Geochemical characteristics of pyrolysis gas from epimetamorphic rocks in the northern basement of Songliao Basin,northeast china

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Science china Earth Sciences 2008年第S1期51卷 140-147页

作者： YANG Chun 1 ,LUO Xia 2 ,LI Jian 2 ,LI ZhiSheng 2 ,liu QuanYou 3 &Wang YuLin 4 1 department of Earth Sciences,Zhejiang university,Hangzhou 310027,china 2 Research Institute of petroleum Exploration and Development(Langfang Branch),Langfang 065007,china 3 Research Institute of petroleum Exploration and Development,Beijing 100083,china 4 department of Source and Environment,Liaoning Technical university,Fuxin 123000,china Zhejiang Univ Dept Earth Sci Hangzhou 310027 Peoples R China Res Inst Petr Explorat & Dev Langfang Branch Langfang 065007 Peoples R China Res Inst Petr Explorat & Dev Beijing 100083 Peoples R China Liaoning Tech Univ Dept Source & Environm Fuxing 123000 Peoples R China

The Xushen gas field,located in the north of Songliao Basin,is a potential giant gas area for china in the *** proved reserves have exceeded 1000×10 8 m 3 by the end of ***,the origin of natural gases from the deep strata is still in *** rocks as a potential gas source are widely spreading in the northern basement of Songliao *** to pyrolysis experiments for these rocks in the semi-confined system,gas production and geochemistry of alkane gases are discussed in this *** Carboniferous-Permian epimetamorphic rocks were heated from 300℃to 550℃,with temperature interval of 50℃.The gas production was quantified and measured for chemical and carbon isotopic *** show thatδ13C 1 is less than?20‰,carbon isotope trend of alkane gas isδ13C 1 δ13C 3 ,these features suggest that the gas would be coal-type gas at high-over maturity,not be inorganic gas with reversal trend of gaseous alkanes (δ13C 1 >δ13C 2 >δ13C 3 ).These characteristics of carbon isotopes are similar with the natural gas from the basin basement,but disagree with gas from the Xingcheng ***,the mixing gases from the pyrolysis gas with coal-typed gases at high-over maturity or oil-typed gases do not cause the reversal trend of carbon *** gas generation intensity for epimetamorphic rocks is 3.0×10 8 ―23.8×10 8 m 3 /km 2 ,corresponding to Ro from 2.0%to 3.5%for organic matter.

关键词： Northern Songliao Basin epimetamorphic rock pyrolysis experiment gas generation potential carbon isotope

A scenario-based clean gasoline production strategy for china National petroleum Corporation

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petroleum Science 2008年第3期5卷 285-294页

作者： liu Haiyan Yu Jianning Fan Yu Shi Gang Bao Xiaojun CNPC Key Laboratory of Catalysis China National Petroleum Corporation China University of Petroleum Beijing102249 China department of R ＆ D Administration. china National petroleum Corp. Beijing 100724 China

Facing increasingly strict environmental regulations on transportation fuels, china National petroleum Corp. （CNPC）, the second largest supplier of petroleum products in china, needs to upgrade its transportation fuels. Using the scenario-based analysis method, this paper analyzes how the emission related properties, including antiknock index, and sulfur, olefin, benzene and aromatics contents of gasoline produced by CNPC, vary with the change in the configuration of gasoline production units in the future 5-15 years. The results showed that for CNPC to upgrade its gasoline, the share of fluid catalytic cracking （FCC） naphtha must be reduced, but just increasing reformate or alkylate and isomerate will result in excessive increase in benzene and aromatics contents or a great loss of gasoline octane number. Therefore, CNPC should suitably control the capacity of its FCC units and increase the capacity of reformer, alkylation and isomerization units. Most importantly, CNPC should dramatically expand the capacity of its hydrotreating or non-hydrotreating gasoline upgrading units to decrease the olefin and sulfur contents in FCC gasoline that takes a dominant share of about 80% in the gasoline pool of china.

关键词： china National petroleum Corporation scenario analysis clean gasoline production