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APPLICATION OF PARAMETRIC DERIVATION METHOD TO THE CALCULATION OF PEIERLS ENERGY AND PEIERLS STRESS IN LATTICE THEORY

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Acta Mechanica Solida Sinica 2007年第4期20卷 363-368页

作者： Xiaozhi wu shaofeng Wang Institute for Structure and Function Chongqing University Chongqing 400044 China

Applying the parametric derivation method, Peierls energy and Peierls stress are calculated with a non-sinusoidal force law in the lattice theory, while the results obtained by the power-series expansion according to sinusoidal law can be deduced as a limiting case of non- sinusoidal law. The simplified expressions of Peierls energy and Peierls stress are obtained for the limit of wide and narrow. Peierls energy and Peierls stress decrease monotonically with the factor of modification of force law. Present results can be used expediently for prediction of the correct order of magnitude of Peierls stress for materials.

关键词： Peierls energy Peierls stress parametric derivation method lattice theory

EXTENDED CORE STRUCTURE OF DISSOCIATED EDGE DISLOCATIONS IN FCC CRYSTALS WITH CONSIDERATION OF DISCRETENESS

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Acta Mechanica Solida Sinica 2008年第5期21卷 403-410页

作者： Xiaozhi wu shaofeng Wang Huili Zhang Institute for Structure and Function Chongqing University Chongqing 400044 China

The extended core structure of the dissociated edge dislocation in Al, Au, Ag, Cu and Ni is determined within lattice theory of dislocation. The 2D dislocation equation governing the displacements is coupled by the restoring forces that are determined by the parameterization of the generalized stacking fault energies. The Ritz variational method is presented to solve the dislocation equation and the trial solution is constituted by two arctan-type functions with two undetermined parameters. The core widths of partial dislocations are wider than that obtained in generalized Peierls-Nabarro model due to the consideration of discreteness of crystal.

关键词： core structure dissociation dislocation equation variational method

Distribution Performance Analysis and Experimental Research on the Port Plate Pairs of Low Speed High Torque Seawater Hydraulic Motor

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Chinese Journal of Mechanical Engineering 2019年第6期32卷 206-218页

作者： Zhiqiang Wang shaofeng wu Dianrong Gao Shuncai Wang School of Mechanical Engineering Hangzhou Dianzi UniversityHangzhou 310018China Zhejiang University Hangzhou 310058China cnCATS Faculty of Engineering and the EnvironmentUniversity of SouthamptonSouthamptonUK School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China

The current research of seawater hydraulic motor mainly focused on piston motor and vane motor, but seldom regarded low speed high torque seawater hydraulic motor. Low speed high torque seawater hydraulic motor as a kind of energy conversion device and actuator plays an important role in seawater hydraulic transmission system. However, the physical and chemical properties of seawater, such as low viscosity, high causticity and poor lubrication, result in numerous problems. In this paper, the flow distribution characteristics of port plate pairs for the seawater hydraulic motor are investigated, and the leakage flow and power loss models of port plate pairs are established. Numerical simulations are carried out to examine the effects of water film, inlet pressure and rotating speed on the pressure distribution and leakage flow. And the friction and wear tests of port plate pairs are also carried out. Moreover, the test system of the seawater hydraulic motor is constructed and the performance of prototype with no-load or loading is conducted. The results indicate that the clearance of port plate pairs and inlet pressure have a significant effect on distribution characteristics, but the effect of rotating speed is not very obvious. The experimental results show that the minimum error rate can be maintained within 0.3% by the proposed flow model and the counter materials of 316 L against carbon-fiber-reinforced polyetheretherketone(CFRPEEK) are suitable for the port plate pairs of seawater hydraulic motor. Finally, based on the seawater hydraulic experiment platform, the volumetric efficiency of no-load and loading are obtained that the maximum can achieve 94.71% and 90.14%, respectively. This research work may improve the flow distribution performance, lubrication and the friction and wear properties, enhance energy converting efficiency of port plate pair and provide theoretical and technical support for the design of highperformance water hydraulic components.

关键词： Seawater hydraulic motor Port plate pairs Leakage flow Clearance Numerical simulation Friction andwear

Experimental Study on Influence of Dimples on Lubrication Performance of Glass Fiber-epoxy Resin Composite under Natural Seawater Lubrication

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Chinese Journal of Mechanical Engineering 2017年第1期30卷 110-117页

作者： wu shaofeng GAO Dianrong LIANG Yingna CHEN Bo School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China Heibei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Yanshan UniversityQinhuangdao 066004China Liren College Yanshan UniversityQinhuangdao 066004China

Bionic non-smooth surface is widely applied in metal and ceramics materials. In order to introduce this technology to high pressure seawater pump, the influence of bionic non-smooth surface on the engineering plastics used in pump should be investigated. The comparative tests are carried out with a ring-on-disc configuration under 800, 1000, 1200 and 1400 r/min in order to research the influence of the bionic non-smooth surface on glass fiber-epoxy resin composite（GF/EPR） under natural seawater lubrication. The disc surfaces are textured with five kinds of pits, which are semi-spherical, conical, cone-cylinder combined, cylindrical pits and through holes, respectively. A smooth surface is tested as reference. The results show that the lubrication performance of dimpled GF/EPR sample is much better than that of the smooth sample under all rotational speeds. The semi-spherical pits surface has more obvious friction reduction than the others, which shows that the least reduction is approximately 43.29% of smooth surface under 1200 r/rain. However, the wear level is only marginally influenced by dimples. The surface morphology investigations disclose severe modifications caused by abrasive wear primarily. The results are helpful to vary friction properties of GF/EPR by non-smooth surface, or provide references to the design of non-smooth surfaces under certain condition.

关键词： !bionic non-smooth surface seawater lubrication friction coefficient glass fiber-epoxy resin composite stainless steel 316L

Influence of Non-smooth Surface on Tribological Properties of Glass Fiber-epoxy Resin Composite Sliding against Stainless Steel under Natural Seawater Lubrication

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Chinese Journal of Mechanical Engineering 2015年第6期28卷 1171-1176页

作者： wu shaofeng GAO Dianrong LIANG Yingna CHEN Bo School of Mechanical Engineering Yanshan University Heibei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Yanshan University Liren College Yanshan University

With the development of bionics, the bionic non-smooth surfaces are introduced to the field of tribology. Although non-smooth surface has been studied widely, the studies of non-smooth surface under the natural seawater lubrication are still very fewer, especially experimental research. The influences of smooth and non-smooth surface on the frictional properties of the glass fiber-epoxy resin composite（GF/EPR） coupled with stainless steel 316 L are investigated under natural seawater lubrication in this paper. The tested non-smooth surfaces include the surfaces with semi-spherical pits, the conical pits, the cone-cylinder combined pits, the cylindrical pits and through holes. The friction and wear tests are performed using a ring-on-disc test rig under 60 N load and 1000 r/min rotational speed. The tests results show that GF/EPR with bionic non-smooth surface has quite lower friction coefficient and better wear resistance than GF/EPR with smooth surface without pits. The average friction coefficient of GF/EPR with semi-spherical pits is 0.088, which shows the largest reduction is approximately 63.18% of GF/EPR with smooth surface. In addition, the wear debris on the worn surfaces of GF/EPR are observed by a confocal scanning laser microscope. It is shown that the primary wear mechanism is the abrasive wear. The research results provide some design parameters for non-smooth surface, and the experiment results can serve as a beneficial supplement to non-smooth surface study.

关键词： non-smooth surface friction coefficient wear resistance glass fiber-epoxy resin composite seawater lubrication stainless steel 316L

Towards a next-generation production system for industrial robots: A CPS-based hybrid architecture for smart assembly shop floors with closed-loop dynamic cyber physical interactions

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Frontiers of Mechanical Engineering 2020年第1期15卷 1-11页

作者： Qingmeng TAN Yifei TONG shaofeng wu Dongbo LI School of Mechanical Engineering Nanjing University of Science&TechnologyNanjing 210094China

Given the multiple varieties and small batches,the production of industrial robots faces the ongoing challenges of flexibility,self-organization,self-configuration,and other“smart”***,cyber physical systems have provided a promising solution for the requirements mentioned *** recent progress,some critical issues have not been fully addressed at the shop floor level,including dynamic reorganization and reconfiguration,ubiquitous networking,and time constrained *** the next generation production system for industrial robots,this study proposed a hybrid architecture for smart assembly shop floors with closed-loop dynamic cyber physical *** for dynamic reorganization and reconfiguration,the study also proposed modularized smart assembly units for the deployment of physical assembly *** technologies,such as multiagent system(MAS),self-organized wireless sensor actuator networks,and edge computing,were discussed and then integrated into the proposed ***,a multijoint robot assembly process was selected as a target ***,an MAS was developed to simulate the coordination and negotiation mechanisms for the proposed architecture on the basis of the Java Agent Development Framework platform.

关键词： cyber physical system robot assembly multiagent system architecture

Specific cross-dimerization of terminal alkynes via Pd/TMEDA catalysis

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Science China Chemistry 2022年第12期65卷 2487-2493页

作者： Lixin Liu Jianyu Dong Zuqi Fu Lebin Su shaofeng wu Qian Shang Shuang-Feng Yin Yongbo Zhou Advanced Catalytic Engineering Research Center of the Ministry of Education College of Chemistry and Chemical EngineeringHunan UniversityChangsha410082China School of Physics and Chemistry Hunan First Normal UniversityChangsha410205China School of Chemistry and Materials Engineering Huizhou UniversityHuizhou516001China

The cross-dimerization of terminal alkynes is the most straightforward and attractive approach to differently substituted 1,3-enynes,which are vital structural motifs in natural products,biologically active compounds,and organic functional materials,***,due to the inherent issues of the stereo-,regio-,and chemoselectivity,the strategy is less explored and remains problematic in substrate scope,selectivity,and screening of catalytic system,***,a specific cross-dimerization of terminal alkynes is developed under Pd/TMEDA catalysis,which produces a series of gem-1,3-enynes(58 examples)in totally moderate to high yields with outstanding functional group tolerance.A cyclopalladium compound might be the key imtermediate,which performs anti-addition-carbometallation,and leads to the exclusive *** unprecedented features of the reaction,such as anti-addition-carbometallation,easy control of selectivity,wide range of the donor alkynes,and very simple catalytic conditions,allow it not only a facile and functionally diverse synthesis of 1,3-enynes,but also a substantial progress for the textbook reaction.

关键词： cross-dimerization Pd/TMEDA catalysis terminal alkynes gem-1,3-enynes

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过渡期泌尿外科—儿童超年龄执业的现状和展望

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中华医学杂志 2024年第14期104卷 1092-1096页

作者：吴少峰孙杰上海交通大学医学院附属上海儿童医学中心泌尿外科上海200127

随着医学的不断进步,更多患有先天性泌尿系统疾病的患儿在得到治疗后顺利成年,使得这些患者从儿童诊疗过渡到成人管理的需求不断增加。过渡期泌尿外科重点关注患有先天性泌尿系统疾病的青少年和年轻人从儿科治疗过渡到成人治疗时的医疗... 详细信息

随着医学的不断进步,更多患有先天性泌尿系统疾病的患儿在得到治疗后顺利成年,使得这些患者从儿童诊疗过渡到成人管理的需求不断增加。过渡期泌尿外科重点关注患有先天性泌尿系统疾病的青少年和年轻人从儿科治疗过渡到成人治疗时的医疗保健需求,最大程度地保障患儿的利益。因上海儿童医学中心获批超年龄连续医疗的资质,本文旨在分析目前在泌尿外科背景下医疗过渡中存在的障碍,探讨以前实施的医疗过渡模型的方式并提出改进建议。

关键词：先天性畸形过渡期泌尿外科小儿泌尿外科

Lycii Radicis Cortex suppresses the growth of non-small cell lung cancer via enhancing the anti-tumor immunity

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Food Science and Human Wellness 2023年

作者： Heng Yin Meng Liu Yaling Zhao Haitao wu Danna Zheng Zhenhui Guo Ying Zhou shaofeng wu Chuanbing Chen Lei Zhang Shanshan Song Yanli He Ren Zhang Research Centre of Basic Intergrative Medicine， School of Basic Medical Sciences， Guangzhou University of Chinese Medicine Science and Technology Innovation Center， Guangzhou University of Chinese Medicine The First Affiliated Hospital of Jinan University School of Pharmaceutical Sciences， Guangzhou University of Chinese Medicine Integrated Hospital of Traditional Chinese Medicine， Southern Medical University Department of Pathology and Pathophysiology， School of Basic Medical Sciences， Guangzhou University of Chinese Medicine

Lycii Radicis Cortex (LRC) is a medicinal and food homologous plant with various pharmacological activities， including anti-tumor effects. This study explores the anti-tumor effect of LRC on non-small cell lung cancer (NSCLC) and its molecular mechanism using mice bearing Lewis lung carcinoma cells. LRC significantly suppressed the growth of NSCLC. Besides， RNA sequencing of mice tumors and hematoxylin & eosin and immunofluorescence staining revealed that LRC promoted the infiltration of T lymphocytes， specifically GZMB+CD8+T lymphocytes， in tumor tissues. The Gene Set Enrichment Analysis of spleen RNA indicated that LRC up-regulated PD-1-downstream pathways， suggesting that LRC exerted its effects through the PD-L1/PD-1 pathway. Further experiments revealed that LRC interacted with PD-L1， blocking PD-L1/PD-1 binding and thus restoring the T cell killing activity on tumor cells. Together， these results support using LRC as healthy food to improve anti-tumor immunity in patients with NSCLC.

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