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HYdrOGENOLYSIS　OF　ARYL　HALIDES　WITH　POWDERS　OF　ALKALI　METAL　HYdrIDES　OF　NANOMETRIC　SIZE

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Chinese Chemical Letters 1995年第8期6卷 735-738页

作者： Zhang, YP Liao, SJ Xu, Y yu, dr Chinese Acad Sci Dalian Inst Chem Phys Dalian 116023 Peoples R China Chinese Acad Sci Shanghai Inst Organ Chem Organomet Chem Lab Shanghai 200032 Peoples R China

Superfine powders of alkali metal hydrides of nanometric size exhibit very high reactivity in the hydrogenolysis of aryl halides.

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CYCLOTRIMERIZATION OF NITRILES BY THE REACTIVE ALKALI METAL HYdrIDES

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Chinese Chemical Letters 1995年第10期6卷 839-842页

作者： Zhang, WM Zhang, L Liao, SJ Xu, Y yu, dr Chinese Acad Sci Dalian Inst Chem Phys Dalian 116023 Peoples R China Chinese Acad Sci Shanghai Inst Organ Chem Organomet Chem Lab Shanghai 200032 Peoples R China

In the presence of reactive alkali metal hydrides, nitriles can be cyclotrimerized to give 2,4,6-trisubstituted-1,3,5-triazines and 2,4,6-trisubstituted imidazoles in moderate yield.

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Carbonylation　of　Allyl　Chloride　Catalyzed　by　PdCl_2（TPPTS）_2　in　Two－phase　Medium

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Chinese Chemical Letters 1996年第9期7卷 847-848页

作者： Jiang, H Xu, Y Liao, SJ yu, dr Chen, H Li, XJ CHINESE ACAD SCI DALIAN INST CHEM PHYSDALIAN 116023PEOPLES R CHINA SICHUAN UNIV DEPT CHEMCHENGDU 610064PEOPLES R CHINA

PdCl2(TPPTS)2 exhibits very high catalytic activity for carbonylation of allyl chloride in aq. NaOH / toluene two-phase medium under atmospheric *** average turnover frequency (TOFav,mol substrate / mol Pd·min) reach... 详细信息

关键词： ATMOSPHERIC-PRESSURE CARBONYLATION SODIUM-HYdrOXIDE HALIDES

An effective method for the hydrodehalogenation of organic halides

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Chinese Science Bulletin 1997年第11期42卷 966-967页

作者： Li, HQ Liao, SJ Xu, Y yu, dr Qiao, ZM CHINESE ACAD SCI DALIAN INST CHEM PHYSDALIAN 116023PEOPLES R CHINA

THE reduction of organic halides to the corresponding hydrocarbons plays an important role inorganic synthesis and environmental *** is one of the earliest reactions de-scribed in the organic chemical literature.A number of successful approaches have been report-ed hitherto,but the hydrodehalogenation of chloroarenes and organic fluorides is still a

关键词： An effective method for the hydrodehalogenation of organic halides

PREPARATION　OF　DI－GRIGNARD　REAGENTS　MEDIATED　BY　THE　TRANSITION　METAL　CHLORIDES

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Chinese Chemical Letters 1995年第4期6卷 301-304页

作者： Zhang, L Liao, SJ Xu, Y yu, dr Zhang, YP Chinese Acad Sci Dalian Inst Chem Phys Dalian 116023 Peoples R China Chinese Acad Sci Shanghai Inst Organ Chem Organomet Chem Lab Shanghai 200032 Peoples R China

In the presence of transition metal chloride and potassium iodide, di-Grignard reagents can be produced efficiently by the reactions of aryl dichlorides with active magnesium species, which are formed in situ from com... 详细信息

关键词： DI OF GRIGNARD PREPARATION CHLORIDES BY

Linear-Quadratic Pareto Cooperative Game for Mean-Field Backward Stochastic System

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Journal of Systems Science & Complexity 2024年第3期37卷 947-964页

作者： WANG yu School of Control Science and Engineering Shandong UniversityJinan 250061China

This paper focuses on a Pareto cooperative differential game with a linear mean-field backward stochastic system and a quadratic form cost functional. Based on a weighted sum optimality method, the Pareto game is equivalently converted to an optimal control problem. In the first place,the feedback form of Pareto optimal strategy is derived by virtue of decoupling technology, which is represented by four Riccati equations, a mean-field forward stochastic differential equation(MF-FSDE),and a mean-field backward stochastic differential equation(MF-BSDE). In addition, the corresponding Pareto optimal solution is further obtained. Finally, the author solves a problem in mathematical finance to illustrate the application of the theoretical results.

关键词： Backward stochastic differential equation linear-quadratic control mean-field Pareto optimality

Approximate analytical solutions for threedimensional ascent trajectory of a solid-fuel launch vehicle with time-varying mass flow rate

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Chinese Journal of Aeronautics 2024年第10期37卷 275-293页

作者： Qi yu Wanchun CHEN Wenbin yu School of Astronautics Beihang UniversityBeijing 102206China

In the scenario that a solid-fuel launch vehicle maneuvers in outer space at high angles of attack and sideslip for energy management,Approximate Analytical Solutions(AAS)for the threedimensional(3D)ascent flight states are derived,which are the only solutions capable of considering time-varying Mass Flow Rate(MFR)at *** uneven MFR makes the thrust vary nonlinearly and thus increases the difficulty of the problem *** AAS are derived based on a 3D Generalized Ascent Dynamics Model(GADM)with a normalized mass as the independent *** simplify some highly nonlinear terms in the GADM,several approximate functions are introduced carefully,while the errors of the approximations relative to the original terms are regarded as minor ***,a finite series with positive and negative exponents,called Exponent-Symmetry Series(ESS),is proposed for function approximation to decrease the highest exponent in the AAS so as to reduce computer round-off *** calculate the ESS coefficients,a method of seeking the Optimal Interpolation Points(OIP)is proposed using the leastsquares-approximation *** to the artful design of the approximations,the GADM can be decomposed into two analytically solvable subsystems by a perturbation method,and thus the AAS are obtained ***,to help implement the AAS,two indirect methods for measuring the remaining mass and predicting the burnout time in flight are put forward using information from *** results verify the superiority of the AAS under the condition of time-varying MFR.

关键词： Approximate analytical solutions 3D ascent trajectory Solid-fuel launch vehicle Uneven thrust Energy management

Low-melting mixture solvents: extension of deep eutectic solvents and ionic liquids for broadening green solvents and green chemistry

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Green Chemical Engineering 2024年第4期5卷 409-417页

作者： yu Chen Zhiwu yu MOE Key Laboratory of Bioorganic Phosphorous Chemistry and Chemical Biology Department of ChemistryTsinghua University

Green solvents such as water and ionic liquids(ILs) are pillars of the great mansion of green chemistry and green processing. Initially proposed as a new family of ILs,deep eutectic solvents(DESs) have received fast development in the past two decades. In this contribution,DESs are reviewed critically and the concept is extended to lowmelting mixture solvents(Lo MMSs),which cover all kinds of materials including ionic compounds,molecular compounds,and metals. Six classes of Lo MMSs are proposed as the new classification system and examples are given. Finally,several thermodynamic issues concerning Lo MMSs are discussed. Two new concepts,robustness of Lo MMSs and high-entropy Lo MMSs,are proposed.

关键词： Green solvents Deep eutectic solvents Low transition temperature mixture solvents Phase diagram EGaIn

Topological Stability and Entropy for Certain Set-valued Maps

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Acta Mathematica Sinica,English Series 2024年第4期40卷 962-984页

作者： yu ZHANG yu Jun ZHU School of Mathematical Sciences Xiamen UniversityXiamen 361005P.R.China

In this paper,the dynamics(including shadowing property,expansiveness,topological stability and entropy)of several types of upper semi-continuous set-valued maps are mainly considered from differentiable dynamical systems points of *** is shown that(1)if f is a hyperbolic endomorphism then for eachε>0 there exists a C^(1)-neighborhood U of f such that the induced set-valued map F_(f,U)has theε-shadowing property,and moreover,if f is an expanding endomorphism then there exists a C^(1)-neighborhood U of f such that the induced set-valued map F_(f,U)has the Lipschitz shadowing property;(2)when a set-valued map F is generated by finite expanding endomorphisms,it has the shadowing property,and moreover,if the collection of the generators has no coincidence point then F is expansive and hence is topologically stable;(3)if f is an expanding endomorphism then for eachε>0 there exists a C^(1)-neighborhood U of f such that h(F_(f,U,ε))=h(f);(4)when F is generated by finite expanding endomorphisms with no coincidence point,the entropy formula of F is ***,the dynamics of the set-valued maps based on discontinuous maps on the interval are also considered.

关键词： Set-valued map orbit space hyperbolic endomorphism perturbation shadowing expansiveness topological stability entropy