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Communications in Theoretical Physics 2008年第8期50卷 303-308页

作者： BAI Cheng-jie ZHAO Hong han ji-guang School of Communication Shandong Normal University Jinan 250014 China School of Physical Science and Information Engineering Liaocheng University Liaocheng 252059 China

A new approach is presented by means of a new general ansitz and some relations among Jacobian elliptic functions, which enables one to construct more new exact solutions of nonlinear differential-difference equations. As an example, we apply this new method to Hybrid lattice, diseretized mKdV lattice, and modified Volterra lattice. As a result, many exact solutions expressible in rational formal hyperbolic and elliptic functions are conveniently obtained with the help of Maple.

关键词： nonlinear differential-difference equations new approach exact solutions

Applications of Extended Hyperbolic Function Method for Quintic Discrete Nonlinear SchrSdinger Equation

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Communications in Theoretical Physics 2007年第3期47卷 474-478页

作者： ZHAO Hong han ji-guang WANG Wei-Tao AN Hong-Yong School of Physical Science and Information Engineering Liaocheng University Liaocheng 252059 China

By using the extended hyperbolic function method, we have studied a quintic discrete nonlinear Schrodinger equation and obtained new exact localized solutions, including the discrete bright soliton solution, dark soliton solution, bright and dark soliton solution, alternating phase bright soliton solution, alternating phase dark soliton solution, and alternating phase bright and dark soliton solution, if a special relation is bound on the coefficients of the equation.

关键词： extended hyperbolic function method quintic discrete nonlinear Schr6dinger equation discretesolitons alternating phase

Solitary Wave and Doubly Periodic Wave Solutions to Three-Dimensional Nizhnik-Novikov-Veselov Equation

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Communications in Theoretical Physics 2008年第5期49卷 1241-1244页

作者： BAI Cheng-jie han ji-guang WANG Wei-Tao AN Hong-Yong Communication School Shandong Normal University Jinan 250014 China Physical Science and Information Engineering School Liaocheng University Liaocheng 252059 China

The generalized transformation method is utilized to solve three-dimensional Nizhnik-Novikov-Veselov equation and construct a series of new exact solutions including kink-shaped and bell-shaped soliton solutions, trigonometric function solutions, and Jacobi elliptic doubly periodic solutions. Among them, the Jacobi elliptic periodic wave solutions exactly degenerate to the soliton solutions at a certain limit condition. Compared with the existing tanh methods and Jacobi function method, the method we used here gives more general exact solutions without much extra effort.

关键词： generalized transformation method (3+1)-dimensional Nizhnik-Novikov-Veselov equation exactsolution KdV equation mKdV equation cubic nonlinear Klein-Gordon equation

Implications for fault reactivation and seismicity induced by hydraulic fracturing

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Petroleum Science 2024年第2期21卷 1081-1098页

作者： Zi-han Sun Ming-guang Che Li-Hong Zhu Shu-Juan Zhang ji-Yuan Lu Chang-Yu jin Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines School of Resources and Civil Engineering and Key Laboratory of Liaoning Province on Deep Engineering and Intelligent TechnologyNortheastern UniversityShenyang110819LiaoningChina Research Institute of Petroleum Exploration&Development PetroChina Company LimitedBeijing100084China The Exploration and Development Research Institute of Daqing Oilfield Limited Company Daqing163458HeilongjiangChina

Evaluating the physical mechanisms that link hydraulic fracturing(HF) operations to induced earthquakes and the anticipated form of the resulting events is significant in informing subsurface fluid injection operations. Current understanding supports the overriding role of the effective stress magnitude in triggering earthquakes, while the impact of change rate of effective stress has not been systematically addressed. In this work, a modified critical stiffness was brought up to investigate the likelihood, impact,and mitigation of induced seismicity during and after hydraulic fracturing by developing a poroelastic model based on rate-and-state fraction law and linear stability analysis. In the new criterion, the change rate of effective stress was considered a key variable to explore the evolution of this criterion and hence the likelihood of instability slip of fault. A coupled fluid flow-deformation model was used to represent the entire hydraulic fracturing process in COMSOL Multiphysics. The possibility of triggering an earthquake throughout the entire hydraulic fracturing process, from fracturing to cessation, was investigated considering different fault locations, orientations, and positions along the fault. The competition between the effects of the magnitude and change rate of effective stress was notable at each fracturing stage. The effective stress magnitude is a significant controlling factor during fracturing events, with the change rate dominating when fracturing is suddenly started or stopped. Instability dominates when the magnitude of the effective stress increases(constant injection at each fracturing stage) and the change rate of effective stress decreases(the injection process is suddenly stopped). Fracturing with a high injection rate, a fault adjacent to the hydraulic fracturing location and the position of the junction between the reservoir and fault are important to reduce the Coulomb failure stress(CFS) and enhance the critical stiffness as

关键词： Hydraulic fracturing Coulomb failure stress Rate-and-state fraction model Linear stability analysis Critical stiffness Seismically induced fault

A molecular insight into coke formation process of vacuum residue in thermal cracking reaction

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Petroleum Science 2024年第3期21卷 2130-2138页

作者： ji-guang Li Xin Guo Huan-Di Hou Heavy Oil Processing Department Sinopec Research Institute of Petroleum Processing Co.LtdBeijing100083China

Understanding the coking behaviors has been considered to be really essential for developing better vacuum residue processing technologies.A battery of thermal cracking tests of typical vacuum residue at 410℃ with various reaction time were performed to evaluate the coke formation *** total yields of ideal components including naphtha,atmospheric gas oil(AGO)and vacuum gas oil(VGO)of thermal cracking reactions increased from 10.89%to 40.81%,and the conversion ratios increased from8.05%to 43.33%with increasing the reaction time from 10 to 70 *** asphaltene content increased from 12.14%to a maximum of 22.39%and then decreased,and this maximum of asphaltene content occurred at the end of the coking induction *** asphaltenes during the coking induction period,at the end and after coking induction period of those tested thermal cracking reactions were characterized to disclose the structure changing rules for coke formation process,and the coke formation pathways were discussed to reveal the coke formation process at molecular level.

关键词： Vacuum residue Thermal cracking Asphaltene Coking induction period Sulfur Nitrogen

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传动比为-1的摆线曲柄槽轮组合机构综合

机械设计 2012年第2期29卷 43-46页

作者：韩继光徐州师范大学机电工程学院江苏徐州221116

当槽轮的槽数一定时,普通槽轮机构的运动系数是定值。用摆线生成机构作为槽轮机构的驱动曲柄,相当于一个变长度、变速度、沿着摆线运动的曲柄,从而改变槽轮机构的运动系数。文中提出了按照运动系数进行组合槽轮机构综合的方法,给出了运... 详细信息

当槽轮的槽数一定时,普通槽轮机构的运动系数是定值。用摆线生成机构作为槽轮机构的驱动曲柄,相当于一个变长度、变速度、沿着摆线运动的曲柄,从而改变槽轮机构的运动系数。文中提出了按照运动系数进行组合槽轮机构综合的方法,给出了运动系数的最大值和最小值的计算方法,以及中位具有瞬时停歇或者近似匀速的组合槽轮机构参数。

关键词：槽轮机构组合机构摆线曲柄运动系数

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偏心渐开线齿轮机构重合度的研究

机械设计 2015年第12期32卷 18-21页

作者：韩继光江苏师范大学机电工程学院江苏徐州221116

偏心渐开线齿轮机构在传动过程中几何中心距是变化的,导致其重合度也随之周期性变化。文中推导了该机构重合度函数;分析了重合度与偏心率、初始压力角、齿数等机构参数的关系。依据重合度≥1的连续传动条件,提出了新的偏心率选择界限—... 详细信息

偏心渐开线齿轮机构在传动过程中几何中心距是变化的,导致其重合度也随之周期性变化。文中推导了该机构重合度函数;分析了重合度与偏心率、初始压力角、齿数等机构参数的关系。依据重合度≥1的连续传动条件,提出了新的偏心率选择界限——最大偏心率确定方法。依据齿轮的不根切条件,建立了齿数选择方程。为偏心渐开线齿轮传动设计提供了必要的理论基础。

关键词：齿轮传动非圆齿轮偏心渐开线齿轮重合度偏心率

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椭圆齿轮槽轮组合机构综合

机械设计 2012年第3期29卷 29-31,73页

作者：韩继光徐州师范大学机电工程学院江苏徐州221116

当槽轮的槽数一定时,普通槽轮机构的运动系数是定值。以椭圆齿轮机构作为槽轮的驱动曲柄,利用椭圆齿轮机构的变传动比特性,可以改变槽轮机构的运动特性。文中分析了机构运动系数的变化规律,给出了最大运动系数和最小运动系数的计算方法... 详细信息

当槽轮的槽数一定时,普通槽轮机构的运动系数是定值。以椭圆齿轮机构作为槽轮的驱动曲柄,利用椭圆齿轮机构的变传动比特性,可以改变槽轮机构的运动特性。文中分析了机构运动系数的变化规律,给出了最大运动系数和最小运动系数的计算方法,提出了按照运动系数进行椭圆齿轮槽轮组合机构综合的方法,以及槽轮中位具有一段匀速运动特性的组合槽轮机构参数。

关键词：机构综合槽轮机构组合机构椭圆齿轮运动系数

Mechanisms of myeloid-derived suppressor cell-mediated immunosuppression in colorectal cancer and related therapies

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1690-1704页

作者： Shu-Chang Nie Yan-Hua jing Lu Lu Si-Si Ren guang ji han-Chen Xu Institute of Digestive Diseases Longhua HospitalChina-Canada Center of Research for Digestive DiseasesShanghai University of Traditional Chinese MedicineShanghai 200032China Shanghai Frontiers Science Center of Disease and Syndrome Biology of Inflammatory Cancer Transformation Shanghai 200032China State Key Laboratory of Integration and Innovation of Classic Formula and Modern Chinese Medicine(Shanghai University of Traditional Chinese Medicine) Shanghai 200032China

Severe immunosuppression is a hallmark of colorectal cancer(CRC).Myeloid-derived suppressor cells(MDSCs),one of the most abundant components of the tumor stroma,play an important role in the invasion,metastasis,and immune escape of *** create an immunosuppressive microenvironment by inhibiting the proliferation and activation of immunoreactive cells,including T and natural killer cells,as well as by inducing the proliferation of immunosuppressive cells,such as regulatory T cells and tumor-associated macrophages,which,in turn,promote the growth of cancer ***,MDSCs are key contributors to the emergence of an immunosup-pressive microenvironment in CRC and play an important role in the breakdown of antitumor *** this narrative review,we explore the mechanisms through which MDSCs contribute to the immunosuppressive microenvironment,the current therapeutic approaches and technologies targeting MDSCs,and the therapeutic potential of modulating MDSCs in CRC *** study provides ideas and methods to enhance survival rates in patients with CRC.

关键词： Myeloid-derived suppressor cells Tumor microenvironment Colorectal cancer Therapy Immunosuppression

A Tri-mode of Mock-Walker Cells

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Advances in Atmospheric Sciences 2024年第4期41卷 671-679页

作者： han QIN ji NIE Zhiyong MENG Laboratory for Climate and Ocean-Atmosphere Studies Department of Atmospheric and Oceanic SciencesSchool of PhysicsPeking UniversityBeijing 100871China China Meteorological Administration Tornado Key Laboratory Foshan 528061China

This work uses cloud-resolving simulations to study mock-Walker cells driven by a specified sea surface temperature(SST).The associated precipitation in the mock-Walker cells exhibits three different modes,including a single peak of precipitation over the SST maximum(mode 1),symmetric double peaks of precipitation straddling the SST maximum(mode 2),and a single peak of precipitation on one side of the SST maximum(mode 3).The three modes are caused by three distinct convective activity center migration *** indicate that the virtual effect of water vapor plays an important role in differentiating the three *** the SST gradient is large,the virtual effect may be strong enough to overcome the temperature effect,generating a low-level low-pressure anomaly below the ascending branch of the Walker cell off the *** results here highlight the importance of the virtual effect of water vapor and its interaction with convection and large-scale circulation in the Walker circulation.

关键词： Walker circulation cloud-resolving simulation virtual effect