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Efficient computation of the compositional model for gas condensate reservoirs

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Communications in Nonlinear Science and Numerical Simulation 2000年第4期5卷 141-146页

作者： Jifu ZHOU, Jiachun li and Jigen YE ({1. of Mechanics, chinese academy of sciences, beijing 100080, china The Research {1. of Petroleum Exploration and Development, beijing 1.0083, china) (Received December 2, 2000) institute of Mechanics Chinese Academy of Sciences Beijing 100080 China Res. Inst. Petrol. Explor./Devmt. Beijing 100083 China

In this paper, a direct method, unsymmetric-pattern multifrontal factorization, for a large sparse system of {1.near equations is app{1.ed in the compositional reservoir model. The good performances of this approach are shown by solving the Poisson equation. And then the numerical module is embedded in the compositional model for simulating X1.(3) gas condensate reservoir in KeKeYa gas field, Northwest china. The results of oil/gas reserves, variations of stratum pressure and oil/gas production, etc. are compared with the observation Good agreement comparable to COMP4 model is achieved, suggesting that the present model is both efficient and powerful in compositional reservoir simulations.

关键词： gas condensate reservoir compositional model sparse matrix

BRST quantization and canonical Ward identity of the supersymmetric electromagnetic interaction system

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Science china(Physics,Mechanics & Astronomy) 2007年第3期50卷 339-347页

作者： HUANG YongChang1,3,4, JIANG YunGuo1 & li XinGuo2,3 1 institute of Theoretical Physics, College of Applied sciences, beijing University of Technology, beijing 100022, china 2 institute of Modern Physics, chinese academy of sciences, Lanzhou 730000, china 3 Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Collisions, chinese academy of sciences, Lanzhou 730000, china 4 china Center of Advanced Science and Technology (World Laboratory), beijing 100080, china institute of Theoretical Physics College of Applied Sciences Beijing University of Technology Beijing China Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Collisions Chinese Academy of Sciences Lanzhou China china Center of Advanced Science and Technology (World Laboratory) Beijing China institute of Modern Physics Chinese Academy of Sciences Lanzhou China

According to the method of path integral quantization for the canonical constrained system in Becchi-Rouet-Stora-Tyutin scheme, the supersymmetric electromagnetic interaction system was quantized. Both the Hamiltonian of the supersymmetric electromagnetic interaction system in phase space and the quantization procedure were simplified. The BRST generator was constructed, and the BRST transforma- tions of supersymmetric fields were gotten; the effective action was calculated, and the generating functional for the Green function was achieved; also, the gauge generator was constructed, and the gauge transformation of the system was ob- tained. Finally, the Ward-Takahashi identities based on the canonical Noether theorem were calculated, and two relations between proper vertices and propaga- tors were obtained.

关键词： supersymmetric electromagnetic interaction BRST quantization Ward identity

Formation of super-concentrated hydrochloric acid in the third phase in tertiary amine N235-PtCl_6^(2-)-HCl system and its influences on the Pt microemulsion extraction

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Science china Chemistry 2009年第11期52卷 1825-1834页

作者： HUANG Kun1.CHEN Jing1.ZHANG ChengFeng1.2,li ZhiHong3,PAN QingHua1.SUN Yan1.liU ShaoXuan1.liU XueXin2,li WeiHong1.YANG ZhanLan1.WENG ShiFu1.HU TianDou3,XU YiZhuang1.& WU JinGuang1.1.College of Chemistry and Molecular Engineering,Peking University,beijing 1.0871.china 2 institute of Chemistry,chinese academy of sciences,beijing 1.01.0,china 3 institute of High Energy Physics,chinese academy of sciences,beijing 1.0049,china College of Chemistry and Molecular Engineering Peking University Beijing China institute of Chemistry Chinese Academy of Sciences Beijing China institute of High Energy Physics Chinese Academy of Sciences Beijing China

In this paper,we have investigated the formation of the third-phase in tertiary amine(N235)-PtCl62--HCl system and the microscopic phase structural evolution of platinum-loaded organic phases before and after the occurrence of the *** third-phase is characterized by various spectroscopic techniques,and the small angle X-ray scattering(SAXS) experiments demonstrate the appearance of nano-aggregates,i.e.,water-in-oil reversed micelles,in the third *** experimental results indicate that(1. formation of the third phase is related to the aggregation behaviors of nano-reversed micelles in which a super-concentrated hydrochloric acid formed with the H+ to H2O molar ratio being much higher than that of the conventional 37 wt% saturated hydrochloric acid.(2) The occurrence of the super-concentrated HCl results in a great amount of H+ and Cl-ions enriched and confined within the nano-water pools of W/O reversed micelles in third ***,the coordination behaviors of platinum complex ions in that super-concentrated hydrochloric acid are very different from their corresponding behaviors in bulk aqueous *** is possible that H+ ions participate in the formation of such complexes as HmPtCl6z+ in the super-concentrated hydrochloric acid.(3) The relative contents of various HmPtCl6z+ complexes are different corresponding to the H+ ion concentrations in confined nanowater *** association abi{1.ty of the acidified tertiary amine N235 molecules(R3NH+) with various HmPtCl6z+ complexes plays an important role in affecting the platinum extraction behaviors.

关键词： solvent extraction third phase super-concentrated hydrochloric acid tertiary amine platinum

Experimental investigation on a parabolic trough solar collector for thermal power generation

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Science china(Technological {1.) 2010年第1期53卷 52-56页

作者： liU QiBin1,wang YaLong1,2,GAO ZhiChao1,2,SUI Jun1,JIN HongGuang1 & li HePing3 1 institute of Engineering Thermophysics,chinese academy of sciences,beijing 100190,china 2 Graduate University of chinese academy of sciences,beijing 100049,china 3 china Huadian Engineering Co.,Ltd,beijing 100044,china institute of Engineering Thermophysics Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China china Huadian Engineering Co. Ltd Beijing China

Developing solar thermal power technology in an effective manner is a great challenge in *** this paper an experiment platform of a parabolic trough solar collector {1.(PTCS) was developed for thermal power generation,and the performance of the PTCS was experimentally investigated with synthetic oil as the circulate heat transfer fluid(HTF).The solar collector's efficiency with the variation of the solar flux and the flow rate of the HTF was *** collector efficiency of the PTCS can be in the range of 40%-60%.It was also found that there existed a specified delay for the temperature of the HTF to response to the solar flux,which played a significant role in designing the *** heat loss effect on collector efficiency was also studied,which was about 220 W/m for the receiver with a 1.0°C temperature difference between the collector temperature and the ambient temperature,amounting to about 1.% of the total solar energy incident on the *** encouraging results can provide fundamental data for developing the parabolic trough solar thermal power plant in china.

关键词： solar energy parabolic trough solar collector collector efficiency lag behind heat loss

STABIliTY OF SWITCHED POLYNOMIAL {1.S

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Journal of systems Science & Complexity 2008年第3期21卷 362-377页

作者： Zhiqiang li Yupeng QIAO Hongsheng QI Daizhan CHENG institute of {1.s Science Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China

This paper investigates the stability of （switched） polynomial {1.s. Using semi-tensor product of matrices, the paper develops two tools for testing the stability of a （switched） polynomial {1.. One is to convert a product of multi-variable polynomials into a canonical form, and the other is an easily verifiable sufficient condition to justify whether a multi-variable polynomial is positive definite. Using these two tools, the authors construct a polynomial function as a candidate Lyapunov function and via testing its derivative the authors provide some sufficient conditions for the global stability of polynomial {1.s.

关键词： Global asymptotical stability semi-tensor product switched polynomial systems

PURE STATE APPROACH TO C(X) x_αZ_n

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chinese Annals of {1.,Series B 1995年第1期16卷 75-86页

作者： li BINGREN liN QING (institute of mathematics, Academia Sinica, beijing 100080, china.) 中科院数学所北京

Consider a C*-system (C(X), z n, α), where α is a homeomorphism of X such that α￣n= *** authors characterize the pure state space of C(X) xα z n) the transition probabi{1.ty and orientation on it. Two special case... 详细信息

关键词： C*-crossed product Pure state space Transition probability Orientation.

Scan chain design for shift power reduction in scan-based testing

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Science china(Information {1.) 2011年第4期54卷 767-777页

作者： li Jia 1.HU Yu 2 & li XiaoWei 2 1.The School of Software,Tsinghua University,beijing 1.0084,china 2 The institute of Computing Technology,chinese academy of sciences,beijing 1.01.0,china The School of Software Tsinghua University Beijing China The institute of Computing Technology Chinese Academy of Sciences Beijing China

Test power of VLSI systems has become a challenging issue *** scan shift power dominates the average test power and restricts clock frequency of the shift phase,leading to excessive thermal accumulation and long test *** paper proposes a scan chain design technique to solve the above *** on weighted transition metric (WTM),the proposed extended WTM (EWTM) that is uti{1.zed to guide the scan chain design algorithm can estimate the scan shift power in both the shift-in and shift-out ***,the wire length overhead of the proposed scan chain design can also be reduced by the proposed distance of EWTM (DEWTM) *** results confirm that the proposed approach can significantly reduce scan shift power with low wire length overhead.

关键词： low power DfT scan-based testing test power reduction scan chain design

Construction of habitat suitability models(HSMs) for benthic macroinvertebrate and their applications to instream environmental flows:A case study in Xiangxi River of Three Gorges Reservior region,china

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Progress in Natural Science:Materials International 2009年第3期19卷 359-367页

作者： Fengqing li a,b, Qinghua Caia,*, Xiaocheng Fu a,b, Jiankang liu a a State Key Laboratory of Freshwater Ecology and Biotechnology, institute of Hydrobiology, chinese academy of sciences, Wuhan 430072, china b Graduate University of chinese academy of sciences, beijing 1.0039, china State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China Graduate University of chinese academy of sciences Beijing 100039 China

Based on a long-term ecological monitoring, the present study chose the most dominant benthic macroinvertebrate (Baetis spp.) as tar- get organisms in Xiangxi River, built the habitat suitability models (HSMs) for water depth, current velocity and substrate, respectively, which is the first aquatic organisms model for habitat suitability in the chinese Mainland with a long-term consecutive in situ measurement. In order to protect the biointegrity and function of the river ecosystem, the theory system of instream environmental flow should be cat- egorized into three hierarchies, namely minimum required instream flow (hydrological level), minimum instream environmental flow (bio- species level), and optimum instream environmental flow (ecosystem level). These three hierarchies of instream environmental flow models were then constructed with the hydrological and weighted usable area (WUA) method. The results show that the minimum required instream flow of Xiangxi River calculated by the Tennant method (1.% of the mean annual flow) was 0.61. m3 s 1. the minimum instream environmental flow accounted for 1..22% of the mean annual flow (namely 1.1.2 m3 s 1., which was the damaged river channel flow in the dry season; and 42.91. of the mean annual flow (namely 2.639 m3 s 1. should be viewed as the optimum instream environmental flow in order to protect the health of the river ecosystem, maintain the instream biodiversity, and reduce the impact of small hydropower stations nearby the Xiangxi River. We recommend that the hydrological and biological methods can help establish better instream environmental flow models and design best management practices for use in the small hydropower station project.

关键词： Habitat suitability model Weighted usable area Instream environmental flow Benthic macroinvertebrate Xiangxi river Three Gorges reservoir

Digitally determining forest inventory units with an ecological classification system

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Science china(Technological {1.) 2006年第Z1期49卷 118-127页

作者： TANG Una, wang Qingli, Guofan Shao, DAI limin, wang Shunzhong, li Xiufen & XU Dong institute of Applied Ecology, chinese academy of sciences, Shenyang 110016, china Graduate University of chinese academy of sciences, beijing 100101, china Department of Forestry and Natural Resources, Purdue University, West Lafayette, IN 47907, USA institute of App{1.ed Ecology Chinese Academy of Sciences Shenyang China Graduate University of chinese academy of sciences Beijing China Department of Forestry and Natural Resources Purdue University West Lafayette USA

Management-level forest resource data in china were obtained with a combination of two forest inventories. However, inconsistencies in the spatial attributes of forest data vary between the two inventory types and between two inventories of the same type. The inconsistencies make it inconvenient for long-term forest management planning with digital technologies. Ecological Land Types (ELTs) and Ecological Land Type Phases (ELTPs) have been mapped in selected forestry regions in northeast china, where important forest industries are located. The boundaries of ELTs are determined by geomorphic conditions, which are quantified by Digital Elevation Models (DEM); ELTPs are classified by overlaying ELTs with forest vegetation data layers that are obtained with both remotely sensed and ground data. The ELTPs represent the divisions of land in terms of both natural and human-induced forest conditions, and therefore they are reliable units for forest inventories and management. This paper introduces a case study for digitally determining forest inventory units in Benxi City, liaoning Province, northeast china. The general objective of the study was to explain how a compatible forest inventory system should be designed and why the compatible forest inventory system was significant to digital forestry in china.

关键词： forest inventory, ecological classification, ELT mapping, ELTP mapping, geographic information systems, forest management.