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Explicit Solutions of (2+1)-Dimensional Canonical Generalized KP, KdV, and (2+1)-Dimensional Burgers Equations with Variable Coefficients

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Communications in Theoretical Physics 2009年第11期52卷 784-790页

作者： ZHANG lin-lin liu xi-qiang School of Mathematical Sciences Liaocheng University Liaocheng 252059 China

In this paper, using the generalized （G1/G）-expansion method and the auxiliary differential equation method, we discuss the （2＋1）-dimensional canonical generalized KP （CGKP）, KdV, and （2＋1）-dimensional Burgers equations with variable coetticients. Many exact solutions of the equations are obtained in terms of elliptic functions, hyperbolic functions, trigonometric functions, and rational functions.

关键词： generalized (G1/G)-expansion method auxiliary equation exact solution

Online Scheduling on a Parallel Batch Machine with Delivery Times and Limited Restarts

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Journal of the Operations Research Society of China 2022年第1期10卷 113-131页

作者： hai-ling liu xi-Wen lu Department of Mathematics East China University of Science and TechnologyShanghai 200237China College of Science Henan University of EngineeringZhengzhou 451191HenanChina

The online scheduling on an unbounded parallel batch machine with delivery times and limited restarts is studied in this ***,online means that jobs arrive over time and the characteristics of a job become known until it *** restarts mean that once a running batch contains at least one restarted job,it cannot be restarted *** goal is to minimize the time by which all jobs have been *** consider a restricted model that the delivery time of each job is no more than its processing *** present a best possible online algorithm with a competitive ratio of 3/2 for the problem.

关键词： Online scheduling Parallel batch Limited restart Delivery time

Sand control mechanism of radial well filled with phase change material in hydrate reservoir

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Petroleum Science 2024年第4期21卷 2571-2582页

作者： xiao-qiang liu Zhong-xi Han Zhi-lin luo hai-Long lu Ying Sun Qing You Tian-Kui Guo Zhan-Qing Qu School of Energy Resources China University of Geosciences(Beijing)Beijing10083China Beijing Key Laboratory of Unconventional Natural Gas Geological Evaluation and Development Engineering China University of Geosciences(Beijing)Beijing10083China China Research Institute of Petroleum Exploration and Development Beijing10083China Engineering Technology Research Institute of Southwest Oil&Gas Field Company PetroChinaChengdu610051SichuanChina Beijing International Center for Gas Hydrate School of Earth and Space SciencesPeking UniversityBeijing100871China School of Advanced Material Peking University Shenzhen Graduate SchoolShenzhen518055GuangdongChina School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580shandongChina

Radial well filled with phase change material has been proposed as a novel sand control method for hydrate *** order to reveal the sand control mechanism,CFD-DEM coupling method is applied to simulate the migration,settlement,and blockage processes of sand particles in the radial *** obtained results indicate that three scenarios have been recognized for sand particles passing through sand control medium,based on the diameter ratio of sand control medium to sand particle(D_(d)):fully passing(D_(d)=8.75-22.5),partially passing and partially blocked(D_(d)=3.18-5.63),and completely blocked(D_(d)=2.18-3.21).After being captured by the sand control medium,sand particles can block pores,which increases fluid flow resistance and causes a certain pressure difference in the radial *** pressure in the radial well should be lower than the hydrate phase equilibrium pressure during sand control design,for the purpose of promoting hydrate decomposition,and sand *** length of the radial well should be optimized based on the reservoir pore pressure,production pressure difference,bottom hole pressure,and the pressure gradient in the radial *** should be noticed that the sand control medium leads to a decrease in permeability after sand particles *** the permeability is reduced to several hundred millidarcy,it is still sufficient to ensure the effective flow of gas and water after hydrate *** fluid velocity reduces the blocking capacity of the sand control medium,mainly because of deterioration in bridging between sand particles.

关键词： Hydrate reservoir Sand control Radial well CFD-DEM

Synthesis of Highly Regioregular, Head-to-Tail Coupled Poly(3-octylesterthiophene) via C―H/C―H Coupling Polycondensation

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Chinese Journal of Polymer Science 2018年第9期36卷 1019-1026页

作者： qiang Zhang Yue-Feng Li lu-Di Deng lin-lin Zhao Chen-xi Li Yan lu Tianjin Key Laboratory for Photoelectric Materials and Devices School of Materials Science & Engineering Tianjin University of Technology Key Laboratory of Functional Polymer Materials State Key Laboratory of Elemento-Organic Chemistry College of Chemistry Nankai University

Highly regioregular, head-to-tail coupled poly（3-octylesterthiophene） was synthesized by the Pd-catalysed oxidative C--H/C--H coupling polycondensation. The regioregularity of polymer products was confirmed by the 1H-NMR technique. Furthermore, the effects of various reaction factors including polymerization temperature, solvents and catalysts etc. on the yield, molecular weight and structural regioregularity of the resultant polymers were systematically studied. The optical, electrochemical and crystallization properties of the resultant P3OET with different HT regioregularities in solution and film state were studied by UV-Vis and fluorescent spectroscopy, cyclic voltammetry and X-ray diffraction （XRD）, resepectively.

关键词： C--H/C--H coupling polymerization Pd catalysed oxidative Poly(thiophene)s

Dynamical phase transitions in a two-species bosonic Josephson junction

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Frontiers of physics 2017年第5期12卷 151-158页

作者： Jing Tian Jun liu hai-Bo Qiu xiao-qiang xi School of Science Xi'an University of Posts and Telecommunications Xi'an 710121 China

We investigate dynamical phase transitions that are induced by interspecies interaction in a two-species bosonic Josephson junctions （B J J）, based on semi-classical theory. In zero-phase mode, similar to the case of a single-species B J J, we observe the well-known dynamical phase transition from Josephson oscillation to self-trapping, which can be induced by both enhanced repulsive and attractive interspecies interactions. In π phase mode, dynamical phase transitions are even more interesting and counter- intuitive. We characterize a dynamical phase transition with the merging of two separate phase space domains into one, which is induced by increasing repulsive interspecies interaction. On the other hand, we find that by increasing attractive interspecies interaction, a phase separation of two formally overlapped phase space domains will occur. At last, we reveal that these intriguing dynamical phase transitions are caused by different kinds of bifurcations.

关键词： dynamical phase transition bosonic Josephson junction

Symmetry, Reductions and New Exact Solutions of ANNV Equation Through Lax Pair

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Communications in Theoretical Physics 2008年第7期50卷 1-6页

作者： ZHANG Li-Hua liu xi-qiang BAI Cheng-lin Department of Mathematics Dezhou University Dezhou 253023 China School of Mathematical Sciences Liaocheng University Liaocheng 252059 China School of Physical Science and Information Engineering Liaocheng University Liaocheng 252059 China

In this paper, the direct symmetry method is extended to the Lax pair of the ANNV equation. As a result, symmetries of the Lax pair and the ANNV equation are obtained at the same time. Applying the obtained symmetry, the （2＋1）-dimensional Lax pair is reduced to （1＋1）-dimensional Lax pair, whose compatibility yields the reduction of the ANNV equation. Based on the obtained reductions of the ANNV equation, a lot of new exact solutions for the ANNV equation are found. This shows that for an integrable system, both the symmetry and the reductions can be obtained through its corresponding Lax pair.

关键词： ANNV equation direct symmetry method Lax pair reductions new exact solutions

Desulfurization of rejected electrolytic manganese metal by electroslag remelting furnace with a water-cooled electrode

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Journal of Iron and Steel Research International 2023年第7期30卷 1411-1425页

作者： Ru lu Ran-ran Yu Guang-qiang Li Yu liu qiang Wang hai-chuan Wang School of Metallurgical Engineering Anhui University of TechnologyMa’anshan 243002AnhuiChina The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081HubeiChina

Remelting rejected electrolytic manganese metal (EMM) scrap was investigated by electroslag remelting (ESR) process through industrial experiment. The results indicated that the ANF-6 slag (70 wt.% CaF_(2) + 30 wt.% Al_(2)O_(3)) and deoxidizer could promote the desulfurization of ESR manganese in an air atmosphere. Under an air atmosphere, the sulfur in the ingot decreased to 0.0534 wt.% with a desulfurization ratio of ESR manganese of 53.2% by using ANF-6 slag and water-cooled copper electrode electroslag remelting rejected EMM scrap, suggesting its efficient removal. The electroslag ingots exhibited uneven chemical composition in an air atmosphere and cooling condition of the ESR process. The metal manganese could be oxidized by electroslag remelting of rejected EMM scrap in an air atmosphere with MnO content in the final slag of 21.9 wt.%. Besides, the activity of MnO in slag increased with increasing remelting temperature, resulting in a reduction in the slag–manganese sulfur partition ratio and desulfurization ratio. Moreover, with the accumulation of sulfur in slag and the oxidation of metallic manganese liquid, the slag showed a lower cleanliness and more oxidation, leading to an increase in sulfur and oxygen content in the electroslag ingot with the increase in ingot height.

关键词： Rejected electrolytic manganese metal scrap Desulfurization Electroslag remelting Thermodynamics

New Multiple Soliton-like and Periodic Solutions for （2＋l）-Dimensional Canonical Generalized KP Equation with Variable Coefficients

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Communications in Theoretical Physics 2006年第5X期46卷 793-798页

作者： ZHANG Li-Hua liu xi-qiang BAI Cheng-lin School of Mathematical Sciences Liaocheng University Liaocheng 252059 China School of Physics Science and Information Engineering Liaocheng University Liaocheng 252059 China

In this paper, the generalized ranch function method is extended to （2＋1）-dimensianal canonical generalized KP （CGKP） equation with variable coetfficients. Taking advantage of the Riccati equation, many explicit exact solutions, which contain multiple soliton-like and periodic solutions, are obtained for the （2＋1）-dimensional OGKP equation with variable coetffcients.

关键词： (2+1)-dimensional canonical generalized (CGKP) equation with variable coefficients tanh function method Riccati equation soliton-like and periodic solutions

Symmetry Groups and New Exact Solutions to （2＋1）-Dimensional Variable Coefficient Canonical Generalized KP Equation

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Communications in Theoretical Physics 2007年第3X期48卷 405-410页

作者： ZHANG Li-Hua liu xi-qiang BAI Cheng-lin Department of Mathematics Dezhou College Dezhou 253023 China School of Mathematical Sciences Liaocheng University Liaocheng 252059 China School of Physics Science and Information Engineering Liaocheng University Liaocheng 252059 China

In this paper, the modified CK＇s direct method to find symmetry groups of nonlinear partial differential equation is extended to （2＋1）-dimensional variable coeffficient canonical generalized KP （VCCGKP） equation. As a result, symmetry groups, Lie point symmetry group and Lie symmetry for the VCCGKP equation are obtained. In fact, the Lie point symmetry group coincides with that obtained by the standard Lie group approach. Applying the given Lie symmetry, we obtain five types of similarity reductions and a lot of new exact solutions, including hyperbolic function solutions, triangular periodic solutions, Jacobi elliptic function solutions and rational solutions, for the VCCGKP equation.

关键词： (2+1)-dimensional variable coefficient canonical generalized KP (VCCGKP) equation modified CK's'direct method symmetry groups Lie symmetry similarity reductions new exact solutions