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A scenario-based clean diesel production strategy for china national Petroleum Corporation

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Petroleum Science 2011年第2期8卷 229-238页

作者： Liu Haiyan Yu Jianning Fan Yu Shi Gang Bao Xiaojun The Key laboratory of Catalysis China National Petroleum Corporation China University of Petroleum Beijing 102249 E R. China Department of R ＆ D Administration China National Petroleum Corporation Beijing 100724 P. R. China

Facing increasingly strict environmental regulations on transportation fuels, china national Petroleum Corporation （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 output and emission related properties, including cetane number, and sulfur and aromatics contents of diesel produced by CNPC, will vary with changes in the configuration of diesel production units in the next 5-10 years. The results showed that, to upgrade its diesel, CNPC needs to adjust its diesel pool by decreasing the share of fluid catalytic cracking （FCC） diesel and increasing the shares of hydrocracking （HDC） and hydrotreating （HDT） diesel. Furthermore, to produce ultra-low-sulfur diesel, straight-run diesel as well as poor diesel blendstocks such as FCC diesel and coker diesel should be hydrotreated before being blended into finished diesel. Developing highly efficient HDC and HDT catalysts and corresponding processes is the key to CNPC economically producing more and cleaner diesel.

关键词： china national Petroleum Corporation scenario analysis clean diesel production

Experimental study of the relationship between fluid density and saturation and sonic wave velocity of rock samples from the WXS Depression,South china Sea

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Petroleum Science 2011年第1期8卷 43-48页

作者： Pei Fagen Zou Changchun He Tao Pan Lingzhi Xiao Kun Shi Ge Ren Keying Key laboratory of Geo-detection（china university of Geosciences Beijing）Ministry of EducationBeijing 100083 China School of Earth and Space Sciences Peking UniversityBeijing 100871China Zhanjiang Branch of china national Offshore Oil Corporation Ltd. Guangdong 524057China

The relationship between fluid density and saturation and sonic wave velocity of rock samples taken from the WXS Depression in the South china Sea was studied by an oil-water replacement experiment under simulated in-situ temperature and pressure *** kinds of low-density oils（0.691 and 0.749 g/cm^3） and two kinds of high-density oils（0.834 and 0.873 g/cm^3） were used to saturate the rock samples at different oil-saturation states,and the saturated P- and S-wave velocities were *** Gassmann＇s equation,the theoretical P- and S-wave velocities were also calculated by the fluid replacement *** the comparison of the measured values and the theoretical values, this study comes to the following conclusions.（1） With the increase of oil saturation and the decrease of water saturation,the P-wave velocity of rock samples saturated by low-density oil increases and the changing rule is in accord with the effective fluid theory;the P-wave velocity of rock samples saturated by high-density oil decreases and the changing rule goes against the theory.（2） With the increase of oil density（namely 0.691→0.749→0.834→0.873 g/cm^3） when oil saturation is unchanged,P-wave velocity increases gradually.（3） The S-wave velocity is always stable and is not affected by the change of oil density and *** results can be used to constrain pre-stack seismic inversion,and the variation rule of sonic wave velocity is valuable for hydrocarbon identification in the study area.

关键词： Rock physics saturation compressional wave shear wave water drive Gassmann's equation fluid replacement

A systematic investigation of high harmonic generation using mid-infrared driving laser pulses

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Science china(Physics,Mechanics & Astronomy) 2010年第6期53卷 1054-1059页

作者： YAO JinPing 1,2 ,XIONG Hui 1 ,XU Han 1 ,FU YuXi 1,2 ,ZENG Bin 1,2 ,CHU Wei 1,2 ,CHENG Ya 1 ,XU ZhiZhan 1 ,LIU XiaoJun 3 & CHEN Jing 4,5 1 State Key laboratory of High Field Laser Physics,Shanghai Institute of Optics and Fine Mechanics,Chinese Academy of Sciences,Shanghai 201800,china 2 Graduate university of Chinese Academy of Sciences,beijing 100049,china 3 State Key laboratory of Magnetic Resonance and Atomic and Molecular Physics,Wuhan Institute of Physics and Mathematics,Chinese Academy of Sciences,Wuhan 430071,china 4 Institute of Applied Physics and computational Mathematics,beijing 100088,china 5 Center for Applied Physics and Technology,Peking university,beijing 100084,china 1. State Key laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan 430071 China4. Institute of Applied Physics and Computational Mathematics Beijing 100088 China5. Center for Applied Physics and Technology Peking University Beijing 100084 China

We report on a systematic investigation of the influences of gas pressure,focal position and focusing geometry on high harmonic generation by use of mid-infrared femtosecond laser pulses. We also discuss the spatial characteristics of harmonics under different focusing conditions. By optimizing the parameters,we experimentally observed the generation of 1 kHz,low divergence coherent X-ray beams in the water-window region.

关键词： mid-infrared laser pulses high harmonic generation water window

Relaying strategy for peer-to-peer content distribution based on genetic algorithm

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The Journal of china Universities of Posts and Telecommunications 2010年第2期17卷 85-91页

作者： HE Qian ,MENG Xiang-wu,SHANG Yan-lei,CHEN Jun-liang State Key laboratory of Networking and Switching Technology,beijing university of Posts and Telecommunications,beijing 100876,china [a] State Key laboratory of Networking Switching Technology Beijing University of Posts Telecommunications Beijing 100876 China

This article proposes a cooperative relaying strategy to efficiently utilize the relaying resources of Interact service providers （ISPs）, speedup distribution and save server bandwidth costs. ISPs cooperatively relay for each other, and peers assist in distributing and fetching the content as near as possible. Base on the fluid model, a constrained model is derived to get optimized global distribution performance in the channel-based system with limited relaying resources. The multi-objectives of the model are minimizing the average distribution time and the distribution time of the slowest channel. Genetic algorithm （GA） is designed to solve the optimization problem. The relaying strategy based on GA can be run periodically to update the allocation policy of ISPs. The distribution performance of the relaying strategy is analyzed in the experiments and results show that GA can provide proper solutions for various network topologies.

关键词： content distribution peer-to-peer genetic algorithm cooperative relaying resource allocation

The influence of thermal radiation on MHD station-point flow past a stretching sheet with heat generation

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Acta Mechanica Sinica 2011年第4期27卷 502-509页

作者： Jing Zhu.Lian-Cun Zheng.Xin-Xin Zhang Department of Mathematics and Mechanics,university of Science and Technology beijing,100083 beijing,china Thermal Engineering Department,university of Science and Technology beijing,100083 beijing,china Zheng Department of Mathematics and Mechanics University of Science and Technology Beijing Beijing China Thermal Engineering Department University of Science and Technology Beijing Beijing China

This letter is concerned with the plane and axisymmetric stagnation-point flows and heat transfer of an electrically-conducting fluid past a stretching sheet in the presence of the thermal radiation and heat generation or absorption. The analytical solutions for the velocity distribution and dimensionless temperature profiles are obtained for the various values of the ratio of free stream velocity and stretching velocity, heat source parameter, Prandtl number, thermal radiation parameter, the suction and injection velocity parameter and magnetic parameter and dimensionality index in the series form with the help of homotopy analysis method （HAM）. Convergence of the series is explicitly dis- cussed. In addition, shear stress and heat flux at the surface are calculated.

关键词： Thermal radiation MHD Laminar boundarylayers - Homotopy analysis method

Hydraulic design and pre-whirl regulation law of inlet guide vane for centrifugal pump

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Science china(Technological Sciences) 2010年第8期53卷 2142-2151页

作者： TAN Lei ,CAO ShuLiang&GUI ShaoBo State Key laboratory of Hydroscience and Engineering,Department of Thermal Engineering,Tsinghua university,beijing 100084,china 1. State Key laboratory of Hydroscience and Engineering Department of Thermal Engineering Tsinghua University Beijing 100084 China

A new hydraulic design method of three-dimensional guide vane for centrifugal pump is proposed on the assumption that the fluid at the outlet of guide vane satisfies the uniform velocity moment *** geometry of blade is controlled by the distributed rule of blade angles along the meridional streamline which is described by a fourth-order *** results demonstrate that the designed guide vane can overcome the drawback of two-dimensional guide vane,enlarge the high efficiency scope and improve the hydraulic performance of centrifugal pump on the off-design operation *** comparison with the performance of the centrifugal pump without inlet guide vane,the peak value of efficiency can be enhanced by 2.13% after the three-dimensional guide vane was being *** three-dimensional entire flow field of the centrifugal pump with inlet guide vane is simulated,and the basic principle and mechanism of inlet guide vane pre-whirl regulation are *** validity of design method has been proved.

关键词： centrifugal pump inlet guide vane pre-whirl regulation hydraulic design method experiment numerical simulation

Formation mechanisms of heavy oils in the Liaohe Western Depression,Bohai Gulf Basin

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Science china Earth Sciences 2008年第S2期51卷 156-169页

作者： LI SuMei1,2,PANG XiongQi1,2,LIU KeYu3,GAO XianZhi1,2,LI XiaoGuang4,CHEN ZhenYan4 & LIU BaoHong41 State Key laboratory of Petroleum Resource and Prospecting,china university of Petroleam,beijing 102249,china 2 Basin and Reservoir Research Center,china university of Petroleum,beijing 102249,china 3 CSIRO Petroleum,P.O. Box 1130,Bentley WA 6102,Australia 4 Liaohe Oilfield Co. Ltd,Petrochina,Panjin 124010,china 1. State Key laboratory of Petroleum Resource and Prospecting China University of Petroleam Beijing 102249 China2. Basin and Reservoir Research Center China University of Petroleum Beijing 102249 China3. CSIRO Petroleum P.O. Box 1130 Bentley WA 6102 Australia4. Liaohe Oilfield Co. Ltd PetroChina Panjin 124010 China

The Liaohe Oilfield in the Liaohe Western Depression of the Bohai Gulf Basin is the third-largest oil producing province and the largest heavy oil producing oilfield in china. A total of 65 oil samples,35 rock samples and 36 reservoir sandstone samples were collected and analyzed utilizing conventional geochemical and biogeochemical approaches to unravel the mechanisms of the formation of the heavy oils. Investigation of the oils with the lowest maturity compared with the oils in the Gaosheng and Niuxintuo oilfields indicates no apparent relation between the maturity and physical properties of the heavy oils. It is suggested that the heavy oil with primary origin is not likely the main mechanism re-sponsible for the majority of the heavy oils in the Liaohe Western Slope. The absence and/or depletion of n-alkanes etc.,with relatively low molecular weight and the occurrence of 25-norhopane series in the heavy oils as well as the relatively high acidity of the oils all suggest that the majority of the heavy oils once experienced secondary alteration. The fingerprints of the total scanning fluorescence (TSF) of the inner adsorbed hydrocarbons on the reservoir grains and the included hydrocarbons in fluid inclusions are similar to that of the normal oils in the area but are different from the outer adsorbed and reser-voired free oils at present,further indicating that most of the heavy oils are secondary in origin. Analyses of bacteria (microbes) in 7 oil samples indicate that anaerobic and hyperthermophilic Ar-chaeoglobus sp. are the dominant microbes relevant to oil biodegradation,which coincides with the shallow commercial gas reservoirs containing anaerobic bacteria derived gas in the Gaosheng and Leijia teotonic belts. The biodegradation most likely occurs at the water/oil interface,where the forma-tion water is essential for microbe removal and nutrient transportation. We think that biodegradation,water washing and oxidization are interrelated and are the main mech

关键词： heavy oil Liaohe Western Depression biodegradation water washing formation mechanism

Preparation of (Ti, Sn)O_2 Nano-Composite Photocatalyst by Supercritical fluid Dry Combination Technology

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Journal of Materials Science & Technology 2005年第2期21卷 191-195页

作者： Jingchang ZHANG, Qing LI and Weiliang CAO Institute of Modern Catalysis, The Key laboratory of Science and Technology of Controllable Chemical Reactions, Ministry of Education, beijing university of Chemical Technology, beijing 100029, china Lab. of Controllable Chem. Reactions Inst. of Modern Catalysis Beijing Univ. of Chem. Technol. Beijing 100029 China

A series of TiO2-SnO2 nano-sized composite photo-catalysts containing Sn (9.3%-30.1%) were prepared from TiCI4 and SnCl4·5H2O by using sol-gel, supercritical fluid dry and solid-phase reaction (SCFD) combination technology. Characterizations with X-ray diffraction (XRD), transmission electron microscopy (TEM) and Fourier Transform Infrared Spectroscopy (FTIR) showed that, in addition to anatase type TiO2, a new active phase (Ti, Sn)O2 (with particle size of 2.0-4.3 nm) formed, and there were no SnO2 crystals observed in the range of the doping concentration studied. Photo-catalytic reaction of phenol was used as a model reaction to evaluate the catalytic activities of the obtained catalysts. Compared with pure TiO2 or Ti-Sn catalyst prepared with general sol-gel method, Ti-Sn nano-composite photo-catalyst thus obtained showed significant improvement in catalytic activity. The photo-catalytic degradation rate of phenol could reach as high as 93.5% after 7 h. The preparation conditions of the new phase (Ti, Sn)O2 were investigated and its catalytic mechanism was proposed. The photo-catalytic particles prepared using SCFD combination technology exhibited small particle size, large surface area and high activity.

关键词： Anatase TiO2 (Ti, Sn)O2 Photo-catalytic Supercritical fluid dry method Solid-phase reaction

A HIGH-ORDER FINITE DIFFERENCE METHOD FOR UNSTEADY CONVECTION-DIFFUSION PROBLEMS WITH SOURCE TERM

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Journal of Hydrodynamics 1999年第2期11卷 97-102页

作者： Yang Zhi-feng Wang Xuan(State Key laboratory of Environment Simulation and Pollution Control, Institute of Environmental Sciences, beijing Normal university, beijing 100875, P. R. china.) beijing Normal Univ Beijing China

The convection and diffusion are the basic processes in fluid flow and heat& mass transfer. The upwind and evolution functions for the convection term are introduced to give a comprehensive transformation to one-dimensional unsteady convection-diffusion equation involving source term. The corresponding compact fourth-order finite difference methed is developed. With the trans formation, the authors overcome the difficultyin dealing with the convection term, and the high-order expression for the convection-diffusion term can be conveniently obtained. The proposed difference scheme with thefourth-order accuracy and unconditional stability can fully reflect the upwind and evolutioneffects of the convection. The calculated results show that the errors of the referencescheme are 600 or 6000 times those of the proposed scheme for the same computationalgrid. With the one time decrease of the space grid, the errors of the proposed scheme andthe reference scheme reduce about 20 times and 2 times respectively. It is evident that theaccuracy of the proposed scheme is remarkably higher than that of the reference scheme.

关键词： convection-diffusion compact difference method comprehensive transformation unsteady computational fluid dynamics