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Chinese Annals of Mathematics,Series B 2021年第1期42卷 135-150页

作者： geng LAI Sisi XIE Department of Mathematics Shanghai UniversityShanghai 200444China

In order to construct global solutions to two-dimensional(2 D for short)Riemann problems for nonlinear hyperbolic systems of conservation laws,it is important to study various types of wave *** paper deals with two types of wave interactions for a 2 D nonlinear wave system with a nonconvex equation of state:Rarefaction wave interaction and shock-rarefaction composite wave *** order to construct solutions to these wave interactions,the authors consider two types of Goursat problems,including standard Goursat problem and discontinuous Goursat problem,for a 2 D selfsimilar nonlinear wave *** classical solutions to these Goursat problems are obtained by the method of *** solutions constructed in the paper may be used as building blocks of solutions of 2 D Riemann problems.

关键词： Nonlinear wave system Rarefaction wave Shock-rarefaction composite wave Wave interaction Characteristic decomposition

Application of the Chemical-Looping Concept for Azoetrope Separation

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Engineering 2021年第1期7卷 84-93页

作者： Xin Gao Xueli geng School of Chemical Engineering and Technology Tianjin University&National Engineering Research Center of Distillation Technology&Collaborative Innovation Center of Chemical Science and Engineering(Tianjin)Tianjin 300350China

The need for the separation of azeotropic mixtures for the production of high-end chemicals and resource recovery has spurred significant research into the development of new separation methods in the chemical *** this paper,a green and sustainable method for azeotrope separation is proposed based on a chemical-looping concept with the help of reversible-reaction-assisted *** central concept in the chemical-looping separation(CLS)method is the selection of a reactant that can react with the azeotrope components and can also be recycled by the reverse reaction to close the loop and achieve cyclic azeotrope *** paper aims to provide an informative perspective on the fundamental theory and applications of the CLS method based on the separation principle,reactant selection,and case analysis,for example,the separation of alkenes,alkane,aromatics,and polyol *** summary,we provide guidance and references for chemical separation process intensification in product refining and separation from azeotropic systems for the development of a more sustainable chemical industry.

关键词： Chemical-looping Azeotropes Reactive distillation Reactants screening Process intensification

Subcellular Localization Analysis of Bovine Foamy Virus Borf1 Protein

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Virologica Sinica 2008年第1期23卷 37-42页

作者： Juan tan Kai WU Rui CHANG Qi-min CHEN Yun-qi geng Wen-tao QIAO The Key Laboratory of Molecular Microbiology and Techaology Ministry of Education and Tianjin Key Laboratory of Microbial Functional Genomics College of Life Sciences Nankai University Tianjin 300071 China

The Borfl protein is encoded by an immediate-early gene of the bovine foamy virus （BFV） and plays a key role in the viral life cycle. Borfl is a DNA binding protein which can transactivate both the long terminal repeat （LTR） and the internal promoter （IP） of BFV by specifically binding to the transactivation responsive element （TRE）. To analyze the subcellular localization of Borfl during the BFV life cycle, this gene was cloned into a prokaryotic expression vector and expressed in a soluble form. After the purification and immunization, we raised the mouse anti-Borfl serum with a high titer based on ELISA results. Western blot analysis showed that the antiserum could specifically recognize the Borfl protein that was expressed in 293T cells. With this specific serum, we revealed the nuclear and cytoplasmic localization of Borfl in HeLa cells that was transfected with Borfl. Moreover, the immuno-fluorescence assay also showed that the localization of Borfl during the infection and transfection of BFV was identical.

关键词： Bovine foamy virus (BFV) Borfl Antiserum

Adaptive Neural Network Dynamic Surface Control for Perturbed Nonlinear Time-delay Systems

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International Journal of Automation and computing 2012年第2期9卷 135-141页

作者： geng Ji School of Mathematics and Information Engineering Taizhou University Linhai 317000 PRC

This paper proposes an adaptive neural network control method for a class of perturbed strict-feedback nonlinear systems with unknown time delays. Radial basis function neural networks are used to approximate unknown intermediate control signals. By constructing appropriate Lyapunov-Krasovskii functionals, the unknown time delay terms have been compensated. Dynamic surface control technique is used to overcome the problem of ＂explosion of complexity＂ in backstepping design procedure. In addition, the semiglobal uniform ultimate boundedness of all the signals in the closed-loop system is proved. A main advantage of the proposed controller is that both problems of ＂curse of dimensionality＂ and ＂explosion of complexity＂ are avoided simultaneously. Finally, simulation results are presented to demonstrate the effectiveness of the approach.

关键词： Adaptive control dynamic surface control neural network nonlinear time delay system stability analysis.

EFFECT　OF　Mn　CONTENT　ON　KINETIC　PARAMETER　DURING　PHASE　TRANSFORMATION　IN　CuZnAlMnNi　SHAPE　MEMORY　ALLOYS

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中国有色金属学会会刊：英文版 1996年第3期6卷 150-152页

作者： geng, GL Bai, YJ SHANDONG UNIV TECHNOL INST MAT ENGNJINAN 250061PEOPLES R CHINA SHANDONG INST MIN & TECHNOL DEPT MECHJINAN 250031PEOPLES R CHINA

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ＥＦＦＥＣＴＯＦＭｎＣＯＮＴＥＮＴＯＮＫＩＮＥＴＩＣＰＡＲＡＭＥＴＥＲＤＵＲＩＮＧＰＨＡＳＥＴＲＡＮＳＦＯＲＭＡＴＩＯＮＩＮＣｕＺｎＡｌＭｎＮｉＳＨＡＰＥＭＥＭＯＲＹＡＬＬＯＹＳ￥ＧｅｎｇＧｕｉｌｉ（ＩｎｓｔｉｔｕｔｅｆｏｒＭａｔｅｒｉａｌｓＥｎｇｉ...

关键词： Mn content CuZnAlMnNi shape memory alloy phase transformation kinetic parameter

Stabilization of coordinated motion for underwater vehicles

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Acta Mechanica Sinica 2011年第3期27卷 438-444页

作者： Fan Wu Zhi-Yong geng State Key Laboratory for Turbulence and Complex Systems Peking University 100871 Beijing China

This paper presents a coordinating and stabilizing control law for a group of underwater vehicles with unstable dynamics. The coordinating law is derived from a potential that only depends on the relative configuration of the underwater vehicles. Being coordinated,the group behaves like one mechanical system with symmetry,and we focus on stabilizing a family of coordinated motions,called relative equilibria. The stabilizing law is derived using energy shaping to stabilize the relative equilibria which involve each vehicle translating along its longest（unstable） axis without spinning,while maintaining a relative configuration within the group. The proposed control law is physically motivated and avoids the linearization or cancellation of nonlinearities.

关键词： Underwater vehicles . Coordination .Relativeequilibria. Stabilization. Energy shaping

A New Understanding of the Sedimentary Environment of the Laiyang Group in the Lower Cretaceous of Lingshan Island,Shandong Province,East China

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Acta Geologica Sinica(English Edition) 2020年第5期94卷 1325-1338页

作者： ZHANG Xiangyu LI Shoujun ZHAO Xiuli geng geng YAN Mingming College of Earth Science&Engineering Shandong University of Science and TechnologyQingdaoShandong 266590China Key Laboratory of Stratigraphy and Palaeontology Ministry of Natural ResourcesBeijing 100037China

The sedimentary background and sedimentary environment of the Lower Cretaceous of Lingshan Island,Shandong,remain *** is considerable controversy as to whether the sedimentary environment was marine or *** this study,analyses were conducted with respect to indicators of paleosalinity,the chemical composition of clay,paleobiota,the characteristics of strata exhibiting salinization in eastern China during the Early Cretaceous,and the relationship between paleosalinity and *** results indicate that the sedimentary environment of the Lower Cretaceous Laiyang Group of Lingshan Island was that of a salified lake rather than a marine *** study not only provides a reference for determining the sedimentary environment of the Lower Cretaceous Laiyang Group of Lingshan Island but also offers a new perspective for the study of Cretaceous strata with salinization characteristics in eastern China.

关键词： paleobiota paleosalinity paleoclimate salified lake Lower Cretaceous Lingshan Island

Consensus intuitionistic fuzzy group decision-making method for aircraft cockpit display and control system evaluation

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Journal of Systems Engineering and Electronics 2013年第4期24卷 634-641页

作者： Tao geng An Zhang Guangshan Lu School of Electronics and Information Northwestern Polytechnical University

A novel group decision-making （GDM） method based on intuitionistic fuzzy sets （IFSs） is developed to evaluate the ergonomics of aircraft cockpit display and control system （ACDCS）. The GDM process with four steps is discussed. Firstly, approaches are proposed to transform four types of common judgement representations into a unified expression by the form of the IFS, and the features of unifications are analyzed. Then, the aggregation operator called the IFSs weighted averaging （IFSWA） operator is taken to synthesize decision-makers’ （DMs’） preferences by the form of the IFS. In this operator, the DM’s reliability weights factors are determined based on the distance measure between their preferences. Finally, an improved score function is used to rank alternatives and to get the best one. An illustrative example proves the proposed method is effective to valuate the ergonomics of the ACDCS.

关键词： aircraft cockpit display and control system (ACDCS) group decision-making (GDM) intuitionistic fuzzy set (IFS) different preference representation weighted averaging (WA) operator.

A time-saving method to assess the efficiency of corrosion inhibitors by electro osmosis

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International Journal of Minerals,Metallurgy and Materials 2011年第3期18卷 370-376页

作者： Chun-lei geng Duan Weng Department of Materials Science and Engineering Tsinghua University Beijing 000 China Beijing Building Materials Academy of Sciences Research （State Key Laboratory） Beijing 100041 China

The corrosion inhibitor is one of the most important technologies to enhance the durability of steel-reinforced concrete. A kind of time-saving method was developed to assess the inhibitor efficiency by using a 32 V electric field to accelerate chloride ion migration in concrete. Potentiodynamic polarization scanning test was used to evaluate the corrosion states. The comprehensive efficiency of an inhibitor should be assessed in two aspects： resistance to chloride ion permeability and inhibiting efficiency. The specimens with different mixing amount of sodium nitrite and migration corrosion inhibitors were used to verify the accuracy and reliability of this method. The results show the differences in inhibiting efficiency of the inhibitors clearly, indicating the reliability of this time-saving method.

关键词： reinforced concrete corrosion corrosion inhibitors corrosion protection

Nanoscale Reciprocating Sliding Contacts of Textured Surfaces:Influence of Structure Parameters and Indentation Depth

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Chinese Journal of Mechanical Engineering 2018年第4期31卷 168-181页

作者： Rui-Ting Tong geng Liu Shaanxi Engineering Laboratory for Transmissions and Controls Northwestern Polytechnical University

Textured surfaces are widely used in engineering components as they can improve tribological properties of sliding contacts, while the detailed behaviors of nanoscale reciprocating sliding contacts of textured surfaces are still lack of study. By using multiscale method, two dimensional nanoscale reciprocating sliding contacts of textured surfaces are investigated. The influence of indentation depth, texture shape, texture spacing, and tip radius on the average friction forces and the running-in stages is studied. The results show that the lowest indentation depth can make all the four textured surfaces reach steady state. Surfaces with right-angled trapezoid textures on the right side are better for reducing the running-in stage, and surfaces with right-angled trapezoid textures on the left side are better to reduce wear. Compared with other textured surfaces, the total average friction forces can be reduced by 82.94%–91.49% for the case of the contact between the tip with radius R = 60rand the isosceles trapezoid textured surface. Besides,the total average friction forces increase with the tip radii due to that bigger tip will induce higher contact areas. This research proposes a detailed study on nanoscale reciprocating sliding contacts of textured surfaces, to contribute to design textured surfaces, reduce friction and wear.

关键词： Nanoscale Reciprocating sliding contacts Textured surface Structure parameters Indentation depth