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Progress in Natural Science:Materials International 2009年第12期19卷 1657-1664页

作者： Lixin Wang,Qiang Zhou~*,Yongjun Zheng,Shuyan Xu department of Mechatronic engineering,china agricultural university,Beijing 100083,china [a]department of Mechatronic engineering China Agricultural University Beijing 100083 China

Pitchers of the carnivorous plant Nepenthes have evolved specialized organs serving the purpose of attracting,capturing,retaining and digesting small animals,mostly *** consist of several well distinguishable zones,including a leaf-like lid,a collar-like peristome, a slippery zone and a digestive zone,differing in morphology,microstructure,chemical composition and physical *** zones display different functions,and the combined effects of several zones result in great trapping *** principal aim of this review is to introduce the structure and physiochemical properties of the pitcher surface,as well as the interaction between the pitcher surface and the insect attachment *** with our present study,the potential application of the pitcher surface being utilized in bionics to manufacture insect slippery trapping plates is discussed,and the original research direction of the pitcher surface and its application on agricultural pest control is highlighted.

关键词： Pitcher surface Nepenthes Composite structure Insect Attachment system

PERTURBATION SOLUTION OF SECONDARY FLOW OF POWER-LAW FLUID IN HELICAL PIPES WITH CIRCULAR CROSS-SECTION

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Journal of Hydrodynamics 2001年第4期13卷 72-78页

作者： Cui Hai-qing, Wang Ke-liang department of Petroleum engineering, Daqing Petroleum Institute, Anda 151400, china Wu Fu-bing department of Navy and Ocean engineering, har.in engineering university, har.in 150001, china Zheng Xiao-song department of Pet Dept. of Petroleum Eng. Daqing Petroleum Inst. Anda 151400 China

In terms of tensor analysis technique, the Navier-Stokes equations in helical coordinate system were derived. A steady incompressible flow of power-law fluid in helical pipes at low Reynolds number was investigated by the perturbation method. A second order solution of secondary flow was worked out. The secondary flow characteristics in helical pipes are analyzed. The effects of the number Dn, curvature and torsion on the secondary flow at different flow parameters were discussed. The results show that the secondary flow pattern changes from a single vortex to two vortices as the number Dn increases at a given curvature and a given torsion. Because of the effect of torsion, the secondary flow pattern changes from two almost symmetrical vortices to a single vortex as the torsion of the helical pipe increases while the Reynolds number and curvature hold constant. The secondary flow pattern cannot be affected by the curvature of the helical pipe at a given Dn number.

关键词： helical pipe secondary flow power-law fluid perturbation method

Spectrofluorimetric determination of terbium with terephthalic acid

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Rare Metals 2002年第4期21卷 255-259页

作者： ZHAO Guohu and ZHAO JunBasic Science department, Gansu agricultural university, Lanzhou 730070, china Basic Science department Gansu Agricultural University Lanzhou 730070

A Spectrofluorimetric method has been developed for the determination ofterbium(Ⅲ) based on the formation of a complex with terephthalic acid [benzene-1, 4-dicarboxylicacid (TPA)] in slightly acidic aqueous solution in the presence of gelatin. Terbium ion can form astable complex with TPA with the stoichiometry of 1:2. The best excitation and maximum emissionwavelengths are observed at 260 nm and 545 nm, respectively. The fluorescence intensity of terbiumcomplex gets the strongest within 20 min and remains stable up to 10 h, and it is proportional toterbium(Ⅲ) concentration in the range of 4.0x10^(-5)-1.6x10^(-7) mol·L^(-1) under the optimumconditions. The fluorescence system has good selectivity, sensitivity and stability. The relativestandard deviation is still within +-4% in the presence of 1200-fold amounts of the other lanthanideions when the concentration of terbium(Ⅲ) is 1.0x10^(-6) mol·L^(-1) and common co-existing ionshardly interfere the determination. It has been applied to the direct fluorimetric determination oftrace terbium (Ⅲ) in rare earth ores and oxides.

关键词： terbium spectrofluorimetry terephthalic acid gelatin

An improved approach to the efficient construction of and search operations in motion graphs

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Science china(Information Sciences) 2012年第5期55卷 1042-1051页

作者： GAO Yan 1,CHEN ZhiHua 2,CHEN MinGang 3 & SHEN Yang 3 1 Software engineering Institute,East china Normal university,Shanghai 200062,china 2 department of Computer Science and engineering,East china university of Science and Technology,Shanghai 200237,china 3 department of Computer Science and engineering,Shanghai Jiao Tong university,Shanghai 200240,china 1. Software engineering Institute East China Normal University Shanghai 200062 China2. Department of Computer Science and Engineering East China University of Science and Technology Shanghai 200237 China3. Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China

Motion graphs have been widely used as an effective technique in the synthesis of human *** synthesize well-formed motions,motion graphs require smooth transitions and good ***,the time and costs grow quadratically as the graph size *** this paper,we present a method to set up a hierarchical structure,called a structure *** coarse level of this graph models different motion categories and their transitions,and the fine level mainly captures different motion *** interpolation space method is used to improve the graph connectivity at the fine *** structure guides the establishment of a faster and more realistic graphical *** the building process,this structure also helps with searching the motion graph,by performing a traverse search and placing the findings into a direct look-up table or local search ***,when there is no direct link between the different motions,a navigation map is introduced to conduct an appropriate search path via a series of transition motion *** experimental results indicate that our approach could lower the computation time in construction and searching,while simultaneously providing a richer variety of motion styles.

关键词： motion graph structure table registration curve motion interpolation

Factors Affecting the Relation of Fracture Toughness V_(GC) with Critical Void Growth Ratio R_C/R_O

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Journal of Materials Science & Technology 1998年第6期14卷 574-576页

作者： Li ZHOU(department of Civil engineering, Wuyi university,Jiangmen 529020, china) department of Civil engineering Wuyi University Jiangmen 529020 China

The relationship between fracture toughness VGC and critical void growth RC/RO was studied for ten kinds of Steel. The macroscopic fracture toughness VGC was determined by using notched tensile specimens. and the microscopic parameters of critical void growth ratio RC/RO were quantitatively measured under SEM. Then, the coefhcient C in the relation VGC = C In(RC/RO) proposed in author's past work was specifically explored. The correlation of C with tensile proderty parameter φ=σyδ/(Eφn) was presented for the Steel investigated, and the effects of low temperature on C were also discussed. Results show that the coefficient C is linearly related to the parameter and insensitive to low temperature.

关键词： GC with Critical Void Growth Ratio R_C/R_O Factors Affecting the Relation of Fracture Toughness V

Analysis on cohesive crack opening displacement considering the strain softening effect

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Science china(Physics,Mechanics & Astronomy) 2006年第1期49卷 88-101页

作者： WANG Limin1, XU Shilang2 & ZHAO Xiqiang3 1. Mechanics department, Shandong university of Technology, Zibo 255049, china 2. Civil engineering department, Dalian university of Technology, Dalian 116024, china 3. Mathematics department, Ocean university of china, Qingdao 266071, china Mechanics department Shandong University of Technology Zibo 255049 China Civil engineering department Dalian University of Technology Dalian 116024 China Mathematics department Ocean University of China Qingdao 266071 China

In order to investigate the crack propagation in quasi-brittle materials like rock, ceramic and concrete, Hillerborg and his co-researchers abstracted the fracture process zone in front of a stress free crack in terms of a “fictitious crack zone”. On the fictitious crack zone, cohesive stresses distribute following a given softening relationship of stress vs. crack opening. Based on the polynomial or power series expression of cohesive crack opening displacement, the relationship of the cohesive stress vs. the crack opening displacement is established using elastic theory and integral equation, and some unknown physics variables are obtained using variation approach. The calculation results gained in this paper are close to the experimentally test ones.

关键词： cohesive crack, softening, dissipation work, variation approach.

Removal of adhesive dusts from flue gas using corona discharges with spraying water

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Journal of Environmental Sciences 2003年第4期15卷 554-561页

作者： XU De\|xuan, ZHAO Jian\|wei, DING Yun\|zheng, GE Wei\|li (department of Environmental Science and engineering, northeast Normal university, Changchun 130024, china. department of Knviranmental Science and engineering Northeast Normal University Changchun 130024

Effective removal of adhesive and fine dusts from flue gas is very difficult. A new method of electrostatic precipitation of the corona discharges with spraying water(CDSW) was introduced. A new electrode configuration and the circulation spraying of water were employed in the method. The efficient electrostatic precipitation for adhesive and fine dusts can be accomplished without any drain water during a long operating period. The fundamental structure, discharge characteristics, mechanism of spraying and precipitation principle of the electrostatic precipitation using CDSW were described and analyzed. The V I characteristics, spraying state, supplying water quantity, influence of temperature and clean of the electrodes were researched in series experiments. The treating effects of circulating spraying using the corona plasma at the same time of electrostatic precipitation were investigated. The fundamental theories and experimental data were proposed, in order to effectively remove the adhesive dusts from flue gas using CDSW in practice.

关键词： aerosol with adhesive dusts corona discharges with spraying water electrostatic precipitation

Guided wave propagation in multilayered piezoelectric structures

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Science china(Physics,Mechanics & Astronomy) 2009年第7期52卷 1094-1104页

作者： GUO YongQiang1, CHEN WeiQiu2,3 & ZHANG YongLiang4 1 Key Laboratory of Mechanics on Disaster and Environment in Western china, Ministry of Education, and School of Civil engineering and Mechanics, Lanzhou university, Lanzhou 730000, china 2 Key Laboratory of Soft Soils and Geoenvironmental engineering, Ministry of Education, and department of Civil engineering, Zhejiang university, Hangzhou 310058, china 3 department of engineering Mechanics, Zhejiang university, Hangzhou 310027, china 4 School of Civil engineering, Lanzhou Jiaotong university, Lanzhou 730070, china Key Laboratory of Mechanics on Disaster and Environment in Western china Ministry of Education and School of Civil Engineering and Mechanics Lanzhou University Lanzhou 730000 China Key Laboratory of Soft Soils and Geoenvironmental engineering Ministry of Education and Department of Civil Engineering Zhejiang University Hangzhou 310058 China department of engineering Mechanics Zhejiang University Hangzhou 310027 China School of Civil engineering Lanzhou Jiaotong University Lanzhou 730070 China

A general formulation of the method of the reverberation-ray matrix (MRRM) based on the state space formalism and plane wave expansion technique is presented for the analysis of guided waves in multilayered piezoelectric structures. Each layer of the structure is made of an arbitrarily anisotropic piezoelectric material. Since the state equation of each layer is derived from the three-dimensional theory of linear piezoelectricity, all wave modes are included in the formulation. Within the framework of the MRRM, the phase relation is properly established by excluding exponentially growing functions, while the scattering relation is also appropriately set up by avoiding matrix inversion operation. Consequently, the present MRRM is unconditionally numerically stable and free from computational limitations to the total number of layers, the thickness of individual layers, and the frequency range. Numerical examples are given to illustrate the good performance of the proposed formulation for the analysis of the dispersion characteristic of waves in layered piezoelectric structures.

关键词： multilayered piezoelectric structures the method of reverberation-ray matrix guided waves dispersion characteristic

Some invariant properties of ordered information systems under homomorphism

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Science china(Information Sciences) 2010年第9期53卷 1816-1825页

作者： WANG ChangZhong1*,CHEN DeGang2 & HU QingHua3 1department of Mathematics,Bohai university,Jinzhou 121000,china 2department of Mathematics and Physics,North china Electric Power university,Beijing 102206,china 3Power engineering,har.in Institute of Technology,har.in 150001,china 1. department of Mathematics Bohai University Jinzhou 121000 China2. Department of Mathematics and Physics North China Electric Power University Beijing 102206 China3. Power Engineering Harbin Institute of Technology Harbin 150001 China

In this paper,some properties of ordered information systems under homomorphism are *** concept of a consistent function with respect to dominance relations is first introduced and its properties are ***,some main invariant properties of dominance relations under relation mappings are *** is proven that attribute reductions in the original ordered information system and its image system are equivalent under the condition of *** means of the results,we can get the smaller image system that has the same reducts as a given massive ordered information system.

关键词： consistent function dominance relation ordered information system homomorphism reduction

Pictet-Spengler condensation reactions catalyzed by a recyclable H^+-montmorillonite as a heterogeneous BrΦnsted acid

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Science china Chemistry 2010年第3期53卷 561-567页

作者： WANG YuFeng,SONG ZhanBo,CHEN ChunXia & PENG JinSong department of Chemistry and Chemical engineering,College of Science,northeast Forestry university,har.in 150040,china 1. department of Chemistry and Chemical engineering College of Science Northeast Forestry University Harbin 150040 China

Catalytic performance of different cation-exchanged montmorillonite clays has been investigated in the Pictet-Spengler C-C bond forming reaction.H+-Montmorillonite was found to be a very efficient and reusable catalyst for the endo cyclization of β-phenylethylamine derivatives with aldehydes under solvent-free *** addition,an aqueous condensation version for the synthesis of tetrahydro-β-carbolines using the H+-montmorillonite catalyst has been *** these environmentally friendly processes,the use of organic solvents was avoided and the catalyst was recycled with maintenance of high catalytic activity.

关键词： heterogeneous catalysis catalyst recycling mesoporous materials green synthesis