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Monodentate phosphorus-coordinated palladium(Ⅱ)complexes as new catalyst for Mizoroki-Heck reaction of aryl halides with electron-deficient olefins

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Chinese Chemical Letters 2018年第3期29卷 493-496页

作者： Fang Zhao Li Xin Yingying Zhang Xuefeng Jia School of Chemical and Material Science Shanxi Normal University Department of Chemistry Modern College of Arts and Sciences Shanxi Normal University

Four novel palladium（（Ⅱ）） complexes coordinated by phosphorus atoms from both 3,5-disubstituted-1H- 1,2,4-diazaphospholes in monodentate fashion were developed as efficient catalyst for the Mizoroki- Heck reaction of aryl halides with electron-deficient olefins. The coupling reaction of awl halide bearig different functional groups with olefin derivatives took place and the corresponding products were isolated in good to excellent yields under optimal conditions. The procedure exhibits good functional group tolerance and wide substrate scope. This Mizoroki-Heck reaction was further achieved using Pd（OAc）2 and 3,5-di-isopropyl-1H-1,2,4-diazaphospholes as combined catalyst, which provide the convenient and alternative method in organic synthesis

关键词： Palladium(Ⅱ) complexes Monodentate phosphine ligands Mizoroki-Heck reaction Aryl halides Olefins

On thermoelastic problem based on four theories with the efficiency of the magnetic field and gravity

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Journal of Ocean Engineering and Science 2024年第4期9卷 338-347页

作者： A.A.Kilany A.N.Abd-alla A.M.Abd-Alla S.M.Abo-Dahab Department of Mathematics Faculty of ScienceSohag UniversitySohag 82524 Egypt Department of Computer Science Faculty of Computers and InformationLuxor UniversityEgypt Department of mathematics Faculty of ScienceSouth Valley UniversityQena 83523Egypt

The fundamental objective of this paper is to study the effectiveness of magnetic field and gravity on an isotropic homogeneous thermoelastic structure based on four theories of generalized *** another meaning,the models of coupled dynamic theory(CDT),Lord-Shulman(LS),Green-Lindsay(GL)as well as Green-Naghdi(GN II)will be taken in the ***,applying the harmonic method(normal mode technique),the solution of the governing equations and the expressions for the components of the displacement,temperature and(Mechanical and Maxwell’s)stresses is taken into account and calculated *** impacts of the gravity and magnetic field are illustrated graphically which are pronounced on the different physical ***,the results of some research that others have previously obtained may be found some or all of them as special cases from this study.

关键词： Generalized thermoelasticity Gravity Magnetic field Green and Naghdi TheoryⅡ normal mode approach

Energy management for multi-microgrid system based on model predictive control

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Frontiers of Information Technology & Electronic Engineering 2018年第11期19卷 1340-1351页

作者： Ke-yong HU Wen-juan Li Li-dong WANG Shi-hua CAO Fang-ming ZHU Zhou-xiang SHOU Qianjiang College Hangzhou Normal University MOE Key Laboratory of Special Purpose Equipment and Advanced Manufacturing Technology Zhejiang University of Technology School of Information Science and Engineering Hangzhou Normal University

To reduce the computation complexity of the optimization algorithm used in energy management of a multi-microgrid system, an energy optimization management method based on model predictive control is presented. The idea of decomposition and coordination is adopted to achieve the balance between power supply and user demand, and the power supply cost is minimized by coordinating surplus energy in the multi-microgrid system. The energy management model and energy optimization problem are established according to the power flow characteristics of microgrids. A dual decomposition approach is imposed to decompose the optimization problem into two parts, and a distributed predictive control algorithm based on global optimization is introduced to achieve the optimal solution by iteration and coordination. The proposed method has been verified by simulation, and simulation results show that the proposed method provides the demanded energy to consumers in real time, and improves renewable energy efficiency. In addition, the proposed algorithm has been compared with the particle swarm optimization(PSO) algorithm. The results show that compared with PSO, the proposed method has better performance, faster convergence, and significantly higher efficiency.

关键词： Microgrids Energy management Predictive control Renewable energy Controllable energy

MOVING RATIO TEST FOR MULTIPLE CHANGES IN PERSISTENCE

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Journal of Systems Science & Complexity 2012年第3期25卷 582-593页

作者： Zhanshou CHEN Zheng TIAN Department of Mathematics Qinghai Normal University Department of Applied Mathematics Northwestern Polytechnical University

This paper proposes a moving ratio test, which is a modified version of ratio test by involving a bandwidth parameter, to detect multiple changes in persistence, and to determine the direction of switch. The asymptotic distribution as well as its consistency are established. In order to estimate the change points, the authors propose a two step estimate approach. Simulations illustrate the performance of the test and estimate procedures in finite samples. An application to the analysis of Sweden/US foreign exchange rate demonstrates the validity of the procedure in practice.

关键词： Bandwidth multiple changes in persistence moving ratio test.

Meshless analysis of an improved element-free Galerkin method for linear and nonlinear elliptic problems

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Chinese Physics B 2017年第3期26卷 215-225页

作者：唐耀宗李小林 College of Mathematics and Statistics Kashgar University College of Mathematics Science Chongqing Normal University

We first give a stabilized improved moving least squares （IMLS） approximation, which has better computational stability and precision than the IMLS approximation. Then, analysis of the improved element-free Galerkin method is provided theoretically for both linear and nonlinear elliptic boundary value problems. Finally, numerical examples are given to verify the theoretical analysis.

关键词： meshless method moving least squares approximation element-free Galerkin method error esti-mate

A simpler method for researching fermions tunneling from black holes

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Chinese Physics B 2011年第11期20卷 110-115页

作者：林恺杨树政 Department of Physics Chongqing University Institute of Theoretical Physics China West Normal University

A new simpler mathematic method is proposed to study fermions tunneling from black holes. According to this method, by using semiclassical approximation theory, it simplifies the Dirac equation of curved spacetime and then the relationship of the gamma matrix and the component of contravariant metric is considered in order to transform the set of difficult quantum equations into a simple equation. Finally, the fermion tunneling and Hawking radiation of black holes are obtained. The method is very effective and simple, and we will take the Schwarzschild black hole with global monopole and the higher-dimensional Reissner-Nordstrom de Sitter black hole as two examples to show the fact.

关键词： black-hole thermodynamics Hawking radiation Schwarzschild black hole higher- dimensional Reissner-Nordstrom de Sitter black hole

Symmetry of solutions for a fractional system

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Science China Mathematics 2017年第10期60卷 1805-1824页

作者： LI Yan MA Pei Department of Mathematical Sciences Yeshiva University School of Mathematical Sciences Nanjing Normal University

We consider a pseudo-differential system involving different fractional orders. Through an iteration method, we obtain the key ingredients—the maximum principles—of the method of moving planes. Then we derive symmet... 详细信息

关键词： the fractional Laplacian narrow region principle decay at infinity method of moving planes radial symmetry

Traveling wave solutions for two nonlinear evolution equations with nonlinear terms of any order

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Chinese Physics B 2011年第12期20卷 17-25页

作者：冯青华孟凡伟张耀明 School of Science Shandong University of Technology School of Mathematical Sciences Qufu Normal University

In this paper, based on the known first integral method and the Riccati sub-ordinary differential equation （ODE） method, we try to seek the exact solutions of the general Gardner equation and the general Benjamin-Bona-Mahoney equation. As a result, some traveling wave solutions for the two nonlinear equations are established successfully. Also we make a comparison between the two methods. It turns out that the Riccati sub-ODE method is more effective than the first integral method in handling the proposed problems, and more general solutions are constructed by the Riccati sub-ODE method.

关键词： first integral method Riccati equation nonlinear equation traveling wave solution

OPTIMAL INVESTMENT AND PROPORTIONAL REINSURANCE IN THE SPARRE ANDERSEN MODEL

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Journal of Systems Science & Complexity 2012年第5期25卷 926-941页

作者： Zhibin LIANG Junyi GUO School of Mathematical Sciences Nanjing Normal University School of Mathematical Sciences Nankai University

From the insurer＇s point of view, this paper studies the optimal investment and proportional reinsurance in the Sparre Andersen model. Under the criterion of maximizing the adjustment coefficient, the authors obtain the closed form expressions of the optimal strategy and the maximal adjustment coefficient, and derive the explicit expression of the ruin probability or its lower bound when the claim sizes are exponentially distributed. Some numerical examples are presented, which show the impact of model parameters on the optimal values. It can also be seen that the optimal strategy to maximize the adjustment coefficient is sometimes equivalent to those which minimize the ruin probability.

关键词： Adjustment coefficient investment proportional reinsurance ruin probability SparreAndersen model.