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Chinese Chemical Letters 2005年第12期16卷 1590-1592页

作者： Sheng jian zhang zhang Gao LE Ningbo Institute of Technology Zhejiang University Ningbo 315100 Department of Applied Chemistry East China Institute of Technology Fuzhou 344000

Reaction of alkanones with 1-butyl-3-methylimidazolium tribromide （[Bmim]Br3） under solvent-free conditions, selectively gave the corresponding ct-bromoalkanones with excellent yields.

关键词： Alkanone ionic liquid [Bmim]Br3

Performance of transmit diversity assisted amplify-and-forward relay system with partial relay selection in mixed Rayleigh and Rician fading channels

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The Journal of China Universities of Posts and Telecommunications 2011年第5期18卷 37-41,46页

作者： XU Wei zhang jian-hua zhang Ping Key Lab of Universal Wireless Communication Ministry of Education. Beijhag University of Posts and Telecommunications Beijing 100876 China Wireless Technology Innovation Institute. Beijing University of Posts and Telecommunications Beijing 100876 China

The performance of transmit diversity （TD） assisted amplify-and-forward （AF） relay system with partial relay selection, which experiences mixed Rayleigh and Rician fading channels, is investigated. We first investigate the closed-form expression of the cumulative distribution function for the end-to-end equivalent signal-to-noise ratio （SNR）, and then the exact expressions of outage probability and average symbol error probability （SEP） are derived. The theoretical observations are verified by the Monte Carlo simulation results.

关键词： transmit diversity amplify-and-forward relay Rician fading

The Regularity of Local Solutions for a Generalized Camassa-Holm Type Equation

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Acta Mathematica Sinica,English Series 2009年第12期25卷 2065-2076页

作者： Shao Yong LAI jian zhang Department of Applied Mathematics Southwestern University of Finance and Economics Chengdu 610074 Po R. China Department of Mathematics Sichuan Normal University Chengdu 610066 P. R. China

The regularity of the Cauchy problem for a generalized Camassa-Holm type equation is investigated. The pseudoparabolic regularization approach is employed to obtain some prior estimates under certain assumptions on the initial value of the equation. The local existence of its solution in Sobolev space Hs （R） with 1 〈 s ≤ 3/2 is derived.

关键词： existence of local solutions Camassa-Holm type equation dissipative term pseudoparabolic regularization method

Eco-environmental Impact Assessment of the Change of Regional Industrial Structure and Regulative Measures

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Chinese Journal of Population,Resources and Environment 2008年第2期6卷 8-17页

作者： zhang jian School of Geographic and Oceanographic Sciences Nanjing University Nanjing Jiangsu 210093 China

Acting as an important driving force for the change of the regional land use,the change of industrial structure also has some influences on the ecological *** assessment and mechanism analysis of these influences will be beneficial to the sustainable development of regional economy and the im- provement of relationships between man and *** Chuzhou City in Anhui Province as an example,on the basis of a qualitative analysis of the influence of the development of differ- ent industry on the regional ecological environment,this paper builds the influence factor of industrial structure on natural envi- ronment and the influence index of industrial structure on natural environment,makes a quantitative assessment of the change of the industrial structure and its comprehensive influences on the eco- logical environment in the Chuzhou City from 1974 to 1995. Studies show that,during the analysed period,Chuzhou City's industrial structure has changed markedly,having undergone two *** influence of industrial structure on natural environment from 1974 to 1995 increased as a whole,while from 1996 to 2004,the influence of industrial structure on natural en- vironment decreased *** changes indicate that the regional change of industrial structure results in better ecological ***,we propose appropriate regulatory measures ac- cording to our research results.

关键词： change of industrial structure eco-environmental effect Chuzhou City measures

Unraveling the condensation reactions of heterometallic {BiNb_(4)} moieties into hybrid Bi_(x)Nb_(y)-oxo clusters with mass spectrometry

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Science China Chemistry 2021年第3期64卷 413-418页

作者： Lv-Bing Yuan Ya-Yong Sun jian zhang Lei zhang State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of Chinese Academy of Sciences Beijing 100049China

The most effective methodologies for the construction of polynuclear complexes usually take advantage of preorganized building ***,we successfully developed a new versatile heterometallic{BiNb_(4)}moiety,which can be applied for the assembly of less explored organic-inorganic hybrid *** controlled condensation reactions,three{BiNb_(4)}moieties can be assembled into a pair of isomeric Bi_(3)Nb_(18)clusters at different temperatures;whilst four{BiNb_(4)}moieties can be combined into two unique Bi_(4)Nb_(16)and Bi_(4)Nb_(18)tetramers in different ***,we have used mass spectrometry to probe the above condensation reactions,which clearly confirmed a stepwise bottom-up assembly process by capturing the presence of bismuth subsalicylate precursors,salicylate coordinated intermediates,Nb incorporated{BiNb_(4)}moieties and the final Bi_(x)Nb_(y)-oxo clusters,***,the packing modes of the{BiNb_(4)}units induce different solution behaviors,and the{BiNb_(4)}units in Bi4Nb16can be recombined by post-synthetic recrystallization in acetonitrile to produce a new tetramer Bi_(4)Nb_(18)-***,this work provides not only a useful{BiNb_(4)}building unit but also the mechanism for their condensation,both of which will promote the future development of metal-oxo clusters.

关键词： cluster compounds mass spectrometry heterometallic complexes condensation reactions

Study on effects of thickness on airfoil-stall at low Reynolds numbers by cusp-catastrophic model based on GA(W)-1 airfoil

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Chinese Journal of Aeronautics 2020年第5期33卷 1444-1453页

作者： Zhiping LI Peng zhang Tianyu PAN Qiushi LI jian zhang National Key Laboratory of Science and Technology on Aero-Engine Aero-thermodynamics Beihang UniversityBeijing 100083China Collaborative Innovation Center for Advanced Aero-Engine Beihang UniversityBeijing 100083China School of Energy and Power Engineering Beihang UniversityBeijing 100083China Key Laboratory of Fluid and Power Machinery Ministry of EducationXihua UniversityChengdu 610039China

The phenomena of an airfoil stall present the behaviors of catastrophe and hysteresis at low Reynolds *** simulation results of two-dimensional airfoil GA(W)-1 show that the width of the hysteresis loop of airfoil stall will gradually decrease and even disappear with the decrease of thickness *** nonlinear characteristics are in accordance with the topological features of the cusp catastrophic *** to the topological invariant principle,a novel topological mapping method is developed to establish the mapping relationship between cusp catastrophic model and stall characteristics of the airfoil,then the effect of thickness ratio on airfoil stall is successfully described quantitatively by cusp catastrophic ***,based on the established topological mapping relationship,combined with the mean flow field of the airfoil stall,potential function approach of cusp catastrophic model is first introduced to interpret the catastrophe and hysteresis of the airfoil stall,and it is found that as the thickness ratio decreases,the system’s maximal potential energy gradually disappears,and the short separation bubble at the leading edge of the airfoil changes to long separation bubble,so the airfoil stall changes from a bistable system to a monostable system.

关键词： Airfoil Catastrophe theory Low Reynolds number Potential function Thickness ratio

Standing Waves of the Inhomogeneous Klein-Gordon Equations with Critical Exponent

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Acta Mathematica Sinica,English Series 2006年第2期22卷 357-366页

作者： Zai Hui GAN jian zhang College of Mathematics and Software Science Sichuan Normal University

This paper is concerned with the standing wave in the inhomogeneous nonlinear Klein- Gordon equations with critical exponent. Firstly, we obtain the existence of standing waves associated with the ground states by using variational calculus as well as a compactness lemma. Next, we establish some sharp conditions for global existence in terms of the characteristics of the ground state. Then, we show that how small the initial data are for the global solutions to exist. Finally, we prove the instability of the standing wave by combining the former results.

关键词： inhomogeneous Klein Gordon equation standing wave ground state global existence blow up instability

Profiles of Blow-up Solutions for the Gross-Pitaevskii Equation

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Acta Mathematicae Applicatae Sinica 2010年第4期26卷 597-606页

作者： Shi-hui Zhu jian zhang College of Mathematics Sichuan UniversityChengdu 610064China College of Mathematics and Software Science Sichuan Normal UniversityChengdu 610066China

This paper is concerned with the blow-up solutions of the Cauchy problem for Gross-Pitaevskii *** terms of Merle and Raphёel＇s arguments as well as Carles＇ transformation,the limiting profiles of blow-up solutions are *** addition,the nonexistence of a strong limit at the blow-up time and the existence of L2 profile outside the blow-up point for the blow-up solutions are obtained.

关键词： Gross-Pitaevskii equation blow-up solution Bose-Einstein condensate limiting profile harmonic potential

Vectorial Variational Principle with Variable Set-Valued Perturbation

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Acta Mathematica Sinica,English Series 2015年第4期31卷 595-614页

作者： jian zhang Jing Hui QIU School of Mathematical Sciences Soochow University

We give a general vectorial Ekeland＇s variational principle, where the objective function is defined on an F-type topological space and taking values in a pre-ordered real linear space. Being quite different from the previous versions of vectorial Ekeland＇s variational principle, the perturbation in our version is no longer only dependent on a fixed positive vector or a fixed family of positive vectors. It contains a family of set-valued functions taking values in the positive cone and a family of subadditive functions of topology generating quasi-metrics. Hence, the direction of the perturbation in the new version is a family of variable subsets which are dependent on the objective function values. The general version includes and improves a number of known versions of vectorial Ekeland＇s variational principle. From the general Ekeland＇s principle, we deduce the corresponding versions of Caristi-Kirk＇s fixed point theorem and Takahashi＇s nonconvex minimization theorem. Finally, we prove that all the three theorems are equivalent to each other.

关键词： Vectorial Ekeland's variational principle F-type topological space locally convex space,pre-ordered linear space direction of perturbation

Aerodynamic Performance Improvement of a Highly Loaded Compressor Airfoil with Coanda Jet Flap

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Journal of Thermal Science 2022年第1期31卷 151-162页

作者： zhang jian DU Juan zhang Min CHEN Ze zhang Hongwu NIE Chaoqun North China Electric Power University Beijing 100096China Advanced Gas Turbine Laboratory Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China Key Laboratory of Advanced Energy and Power Chinese Academy of SciencesBeijing 100190China Innovation Academy for Light-Duty Gas Turbine Chinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100190China Changsha University of Science&Technology Changsha 410114China

Coanda jet flap is an effective flow control technique,which offers pressurized high streamwise velocity to eliminate the boundary layer flow separation and increase the aerodynamic loading of compressor ***,there is only single-jet flap on the blade suction side.A novel Coanda double-jet flap configuration combining the front-jet slot near the blade leading edge and the rear-jet slot near the blade trailing edge is proposed and investigated in this *** reference highly loaded compressor profile is the Zierke&Deutsch double-circular-arc airfoil with the diffusion factor of ***,three types of Coanda jet flap configurations including front-jet,rear-jet and the novel double-jet flaps are designed based on the 2D flow fields in the highly loaded compressor blade *** Back Propagation Neural Network(BPNN)combined with the genetic algorithm(GA)is adopted to obtain the optimal geometry for each type of Coanda jet flap *** simulations are then performed to understand the effects of the three optimal Coanda jet flaps on the compressor airfoil *** indicate all the three types of Coanda jet flaps effectively improve the aerodynamic performance of the highly loaded airfoil,and the Coanda double-jet flap behaves best in controlling the boundary layer flow *** the inlet flow condition with incidence angle of 5°,the total pressure loss coefficient is reduced by 52.5%and the static pressure rise coefficient is increased by 25.7%with Coanda double-jet flap when the normalized jet mass flow ratio of the front jet and the rear jet is equal to 1.5%and 0.5%,*** impacts of geometric parameters and jet mass flow ratios on the airfoil aerodynamic performance are further *** is observed that the geometric design parameters of Coanda double-jet flap determine airfoil thickness and jet slot position,which plays the key role in supressing flow separation on the airfoil suction ***

关键词： Coanda jet flap high loaded compressor active flow control aerodynamic performance