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New Families of Exact Excitations to （2＋1）-Dimensional Toda Lattice System via an Extended Projective Approach

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Communications in Theoretical Physics 2006年第5期45卷 864-868页

作者： FANG jian-Ping FEI jin-xi ZHENG Chun-Long College of Physics and Mathematics Lishui University Lishui 323000 China Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072China

In this paper, the extended projective approach, which was recently presented and successfully used in some continuous nonlinear physical systems, is generalized to nonlinear partial differential-difference systems （DDEs）, As a concrete example, new families of exact solutions to the （2＋1）-dimensional Toda lattice system are obtained by the extended projective approach.

关键词： extended projective approach DDEs Toda lattice exact solution

Efficient oxidation of benzyl alcohol with heteropolytungstate as reaction-controlled phase-transfer catalyst

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Chinese Chemical Letters 2007年第8期18卷 936-938页

作者： Zhi Huan Weng jin Yan Wang xi Gao jian Department of Polymer Science and Materials Dalian University of Technology Liaoning Research Center of High Performance Resin Engineering and Technology Dalian 116012 China

A series of heteropolytungstates has been synthesized and utilized as catalysts to catalyze oxidation of benzyl alcohol with aqueous hydrogen peroxide. The results indicated that three of these catalysts showed the properties of reaction-controlled phasetransfer catalysis, and they had excellent catalytic ability to the oxidation of benzyl alcohol. No other by-products were detected by gas chromatography. Once the hydrogen peroxide was consumed completely, the catalyst precipitated from solvent, and the results of the catalyst recycle showed that the catalyst had high stability.

关键词： Heteropolytungstate Reaction-controlled phase-transfer Benzyl alcohol Benzaldehyde Hydrogen peroxide

Synthesis and Characterization of Poly(ether imide)s Containing m-Methyl and Phthalazinone Moieties

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Chinese Chemical Letters 2003年第4期14卷 331-332页

作者： jin Yan WANG Shu De xiAO xi Gao jian Department of Polymer Science&Materials Dalian University of TechnologyDalian 116012

Three novel poly(ether imide)s were synthesized by one-step solution polymerization from 2-(3, 4-dicarboxyl-N-phenyl)-4-(3, 4-dicarboxyl-phenoxyl-4-(2-methyl)-phenyl)-2, 3- phthal-azin-1-one dianhydride and three amin... 详细信息

关键词： Synthesis poly(ether imide)s phthalazinone dianhydride.

Synthesis and Characterization of Poly (ether imide)s Containing Phthalazinone and Isopropyl Moieties

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Chinese Chemical Letters 2001年第7期12卷 593-594页

作者： jin Yan WANG xi Gao jian Shu De xiAO Department of Polymer Science&Material College of Chemical EngineeringDalian University of TechnologyDalian 116012

A novel poly(ether imide)s containing phthalazinone and isopropyl moieties derived from 2-(4-aminophenyl)-4-[4-(4-aminophenoxy)phenyl]-phthalazin-1-one and bisphenol-A diphthalic anhydride was synthesized by one-step solution condensation polymerization in nr-cresol. The polymer was characterized by FTIR, NMR, molecular weights, glass transition temperature, thermal degradation temperature and WAXD.

关键词： Poly (ether imide) s phthalazinone one-step solution condensation polymerization

Heteropolymolybdate as a New Reaction-controlled Phase-transfer Catalyst for Efficient Alcohol Oxidation with Hydrogen Peroxide

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Chinese Chemical Letters 2006年第6期17卷 848-850页

作者： Zhi Huan WENG jin Yan WANG xi Gao jian Department of Polymer Science and Materials Dalian University of TechnologyLiaoning High Performance Polymer Engineering Research Center Dalian 116012

A new catalytic process for the synthesis of aldehyde from alcohol by oxidation with H202 with high selectivity, was studied. In this system, heteropolymolybdate [C7H7N（CH3）3]3 {PO4[MoO（O2）2]4} was utilized as the reaction-controlled phase-transfer catalyst to catalyze oxidation of benzyl and aliphatic alcohols. The molar ratio of H2O2 and alcohol was 0.75, no other by-products were detected by gas chromatography, the results of oxidation reaction indicated that the catalyst has high activity and stability.

关键词： Heteropolymolybdate reaction-controlled phase-transfer alcohol oxidation.

A New Pregnane Glycoside from Fermented Leaves of Agave americana

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Chinese Chemical Letters 2002年第12期13卷 1189-1192页

作者： jian Ming jin xi Kui LIU Chong Ren YANG State Key Laboratory of Phytochemistry and Plant Resources of West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650204

A new minor pregnane glycoside was isolated from the fermented leaves of Agave americana. Its structure was elucidated as (20S)-5a-pregnane-3? 20-diol 20-O--D-glucopyrano- side (1) by spectral methods.

关键词： Agave americana L. pregnane glycoside.

Experimental investigation on using CO_(2)/H_(2)O emulsion with high water cut in enhanced oil recovery

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Petroleum Science 2024年第2期21卷 974-986页

作者： xi-Dao Wu Peng xiao Bei Liu Guang-jin Chen jian-Hua Pang State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China Ocean Intelligence Technology Center Shenzhen Institute of Guangdong Ocean UniversityShenzhen518120GuangdongChina

CO_(2) emulsions used for EOR have received a lot of interest because of its good performance on CO_(2)mobility ***,most of them have been focusing on the high quality CO_(2) emulsion(high CO_(2) fraction),while CO_(2) emulsion with high water cut has been rarely *** this paper,we carried out a comprehensive experimental study of using high water cut CO_(2)/H_(2)O emulsion for enhancing oil ***,a nonionic surfactant,alkyl glycosides(APG),was selected to stabilize CO_(2)/H_(2)O emulsion,and the corresponding morphology and stability were evaluated with a transparent PVT ***,plugging capacity and apparent viscosity of CO_(2)/H_(2)O emulsion were measured systematically by a sand pack displacement apparatus connected with a 1.95-m long capillary ***,a high water cut(40 vol%) CO_(2)/H_(2)O emulsion was selected for flooding experiments in a long sand pack and a core sample,and the oil recovery,the rate of oil recovery,and the pressure gradients were *** results indicated that APG had a good performance on emulsifying and stabilizing CO_(2) *** inversion from H_(2)O/CO_(2) emulsion to CO_(2)/H_(2)O emulsion with the increase in water cut was ***_(2)/H_(2)O emulsions with lower water cuts presented higher apparent viscosity,while the optimal plugging capacity of CO_(2)/H_(2)O emulsion occurred at a certain water ***,the displacement using CO_(2)/H_(2)O emulsion provided 18.98% and 13.36% additional oil recovery than that using pure CO_(2) in long sand pack and core tests,*** work may provide guidelines for EOR using CO_(2) emulsions with high water cut.

关键词： CO_(2)/H_(2)O emulsion High water cut CO_(2) mobility control Enhanced oil recovery

Study on the Influence of Piloti on Mean Radiant Temperature in Residential Blocks by 3-D Unsteady State Heat Balance Radiation Calculation

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Journal of Harbin Institute of Technology(New Series) 2014年第4期21卷 91-95页

作者： Tian-Yu xi jian-Hua Ding Hong jin School of Architecture Harbin Institute of Technology School of Architecture Tsinghua University

Piloti is commonly used in tropical and subtropical climate zones to get high wind velocity and create shadowed areas in order to optimize the living environment of residential blocks,but there are few studies to reveal the influence of piloti on the radiant environment of residential blocks systematically. Taking the city of Guangzhou as an example,using 3-D Unsteady State Heat Balance Radiation Calculation Method,this paper shows that the mean radiant temperature( MRT) under piloti area increases with the increase of piloti ratio,and especially when piloti ratio is equal to 100%,the MRT increase trend becomes sharp. The MRT of exposed area decreases with the increase of piloti ratio,especially when piloti ratio reaches 100%,the decrease trend of MRT becomes sharp,which offers the reference for the study on piloti design in subtropical climate zones and further research on living environment by CFD simulation in residential blocks.

关键词： piloti mean radiant temperature 3-D unsteady state heat balance radiation calculation residential block

Modeling the dynamical friction timescale of a sinking satellite

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Research in Astronomy and Astrophysics 2010年第12期10卷 1242-1254页

作者： jian-Ling Gan xi Kang jin-Liang Hou Rui-xiang Chang Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China jlgan@*** Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

When a satellite galaxy falls into a massive dark matter halo, it suffers from the dynamical friction force which drags it into the halo＇s center, where it finally merges with the central galaxy. The time interval between entry and merger is called the dynamical friction timescale （Tdf）. Many studies have been dedicated to deriving Tdf using analytical models or N-body simulations. These studies have obtained qualitative agreements on how Zdf depends on the orbital parameters, and the mass ratio between the satellite and the host＇s halo. However, there are still disagreements on deriving an accurate form for Tdf. We present a semi-analytical model to predict Tdf and we focus on interpreting the discrepancies among different studies. We find that the treatment of mass loss from the satellite by tidal stripping dominates the behavior of Tdf. We also identify other model parameters which affect the predicted Tdf.

关键词： methods: analytical -- methods: numerical-- galaxies: haloes -- galax-ies: evolution -- galaxies: interactions -- cosmology: dark matter