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Effect of adenovirus-mediated brain derived neurotrophic factor in early retinal neuropathy of diabetes in rats

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International Journal of Ophthalmology(English edition) 2010年第2期3卷 145-148页

作者： chao wan Ning-Ning Liu Li-min Liu Na Cai and Lei Chen Department of Ophthalmology the First Affiliated Hospital of China Medical University Shenyang 110001 Liaoning Province China

AIMTo observe effect of adenovirus-mediated brain derived neurotrophic factor in early retinal neuropathy of diabetes in rats.

关键词： diabetic retinopathy tyrosine hydroxylase brain derived neurotrophic factor adenovirus

Basic quantities of the equation of state in isospin asymmetric nuclear matter

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Nuclear Science and Techniques 2021年第11期32卷 1-12页

作者： Jie Liu chao Gao Niu wan Chang Xu School of Physics Nanjing UniversityNanjing 210093China School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510641China

Based on the Hugenholtz-Van Hove theorem six basic quantities of the EoS in isospin asymmetric nuclear matter are expressed in terms of the nucleon kinetic energy t(k),the isospin symmetric and asymmetric parts of the single-nucleon potentials U_(0)(ρ,k)and U_(sym,i)(ρ,k).The six basic quantities include the quadratic symmetry energy E_(sym,2)(ρ),the quartic symmetry energy E_(sym,4)(ρ),their corresponding density slopes L_(2)(ρ)and L_(4)(ρ),and the incompressibility coefficients K_(2)(ρ)and K_(4)(ρ).By using four types of well-known effective nucleon-nucleon interaction models,namely the BGBD,MDI,Skyrme,and Gogny forces,the density-and isospin-dependent properties of these basic quantities are systematically calculated and their values at the saturation density q_(0)are explicitly *** contributions to these quantities from t(k)U_(0)(ρ,k),and U_(sym,i)(ρ,k)are also analyzed at the norma nuclear density q_(0).It is clearly shown that the first-order asymmetric term U_(sym,1)(ρ,k)(also known as the symmetry potential in the Lane potential)plays a vital role in determining the density dependence of the quadratic symmetry energy E_(sym,2)(ρ).It is also shown that the contributions from the high-order asymmetric parts of the single-nucleon potentials(U_(sym,i)(ρ,k)with i>1)cannot be neglected in the calculations of the other five basic quantities Moreover,by analyzing the properties of asymmetric nuclear matter at the exact saturation densityρ_(sat)(δ),the corresponding quadratic incompressibility coefficient is found to have a simple empirical relation K_(sat,2)=K_(2)(ρ_(0))-4.14L_(2)(ρ_(0))

关键词： Equation of state Symmetry energy HVH theorem Single-nucleon potential

Reactive-sintering B_4C matrix composite for armor applications

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Rare Metals 2020年第5期39卷 529-544页

作者： chao Wu Yun-Kai Li Chun-Lei wan Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology Nanjing Institute of TechnologyNanjing 211167China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

The B4C matrix composite intended for armor applications still presents restrictions,such as low sintering density,production of large parts and inherited brittleness Herein,research on this topic is discussed in *** the material outlook of armor applications is organized from the development of composite armor and ceramic materials for armor to the B4C matrix composite and reactive-sintering *** the second section,the technologies are reviewed for reactive pressureless sintering reactive hot-pressing sintering,reactive discharge plasma sintering and self-propagating high-temperature sintering Thereafter,our previous works on the TiB2/SiC/B4C composite and laminated Ti/B4C composite are employed to illustrate their microstructural evolution,phase transformation and fracture *** studies provide a potential method for producing tough and high-strength ceramic composites for armor *** the fina section,the mechanism,evaluation method and influencing factors of anti-penetration for ceramic armor and B4C matrix composite are reviewed.

关键词： Composite armor B4C matrix composite Reactive sintering Mechanical properties

Effects of process parameters and annealing on microstructure and properties of CoCrFeMnNi high-entropy alloy coating prepared by plasma cladding

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China Foundry 2023年第6期20卷 491-502页

作者： Shi-yong Wei chao-min wang Wen-yi Peng Ru-kai Luo Yun Chen Zhen-zhen wan Yin Jin Institute of Applied Physics Jiangxi Academy of SciencesNanchang 330090China Materials Science and Engineering School Nanchang UniversityNanchang 330029China

Plasma cladding was used to prepare a CoCrFeMnNi high-entropy alloy(HEA)coating under different *** process parameters were optimized using an orthogonal experiment design based on surface morphology quality characteristics,dilution rate,and *** optimal process parameters were determined through range and variance analysis to be a cladding current of 70 A,a cladding speed of 7 cm·min^(-1),and a powder gas flow rate of 8 L·s^(-1).During the optimized experiments,both the cladded and annealed CoCrFeMnNi HEA coatings exhibit some pores,micro-voids,and a small amount of ***,the aggregation in the annealed coating is more dispersed than that in the cladded *** cladded CoCrFeMnNi HEA coating consists of simple FCC phases,while a new Cr-rich phase precipitates from the FCC matrix after annealing the coating at a temperature range of 550℃-950℃.After annealing at 850℃,the proportion of the FCC phase decreases compared to the cladded coating,and the number of large-angle grain boundaries is significantly ***,the proportion of grains with sizes below 50μm increases from 61.7%to 74.3%.The micro-hardness and wear resistance of the cladded coating initially increases but then decreases with an increase in annealing temperature,indicating that appropriate annealing can significantly improve the mechanical properties of the CoCrFeMnNi HEA coatings by plasma *** micro-hardness of the CoCrFeMnNi HEA coatings after annealing at 650℃ increases to 274.82 HV_(0.2),while the friction coefficient decreases to below 0.595.

关键词： plasma cladding CoCrFeMnNi HEA coating process optimization annealing microstructure and mechanical property

Design of a tunable mass damper for mitigating vibrations in milling of cylindrical parts

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Chinese Journal of Aeronautics 2019年第3期32卷 748-758页

作者： Heng YUAN min wan Yun YANG School of Mechanical Engineering Northwestern Polytechnical University State IJR Center of Aerospace Design and Additive Manufacturing Northwestern Polytechnical University

Milling the free-end of cylindrical parts, which are vertically fixed on the machine table,often suffers from large chatter vibrations. This kind of phenomenon is harmful to the cutting process. Therefore, it is of great importance to develop means to suppress these undesirable *** paper proposes a new idea for designing a tunable mass damper(TMD) to reduce vibrations in milling of cylindrical parts. Frequency response function(FRF) of the milling system is derived to comprehensively reveal the influence of both the dynamic response of the machine tools and the TMD. Critical axial depth of cut, which is usually used to characterize the process stability, is formulated by considering the FRFs of both the milling system itself and the TMD. Maximization of critical axial depth of cut is taken as objective function, while kernel dynamic parameters of TMD,which are involved in the derived expression of critical axial depth of cut, are extracted as designable variables. Optimization procedure is carried out to adjust the parameters of TMD by using sequential quadratic programming algorithm. A series of experiments with a designed passive TMD validate that the design has a good performance in reducing vibrations and improving stability of milling process.

关键词： Chatter Milling Mitigation of vibrations Stability Tunable mass damper (TMD)

Post-spin crossing dynamics determine the regioselectivity in open-shell singlet biradical recombination

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Organic Chemistry Frontiers 2022年第4期9卷 995-1003页

作者： min Zhu chao Zheng State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of Sciences345 Lingling LuShanghai 200032China School of Physical Science and Technology ShanghaiTech University100 Haike RoadShanghai 201210China

Radical recombination is among the fastest reactions in organic *** high levels of selectivity in this type of reaction is rather *** a recent report on visible-light-induced dearo-mative cycloaddition of pyrrole-tethered vinylcyclopropanes,extraordinary regioselectivity was observed during the intramolecular open-shell singlet biradical recombination step.

关键词： singlet radical regioselectivity

Structure and function of WD40 domain proteins

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Protein & Cell 2011年第3期2卷 202-214页

作者： chao Xu Jinrong min Structural Genomics Consortium University of Toronto101 College St.TorontoOntarioM5G 1L7Canada Department of Physiology University of TorontoTorontoOntario M5S 1A8Canada

The WD40 domain exhibits aβ-propeller architecture,often comprising seven *** WD40 domain is one of the most abundant domains and also among the top interacting domains in eukaryotic *** this review,we will discuss the identification,definition and architecture of the WD40 ***40 domain proteins are involved in a large variety of cellular processes,in which WD40 domains function as a protein-protein or protein-DNA interaction ***40 domain mediates molecular recognition events mainly through the smaller top surface,but also through the bottom surface and *** far,no WD40 domain has been found to display enzymatic *** will also discuss the different binding modes exhibited by the large versatile family of WD40 domain *** the last part of this review,we will discuss how post-translational modifications are recognized by WD40 domain proteins.

关键词： WD40 beta-propeller protein-protein interaction scaffold post-translational modification

Vibration Control of A Flexible Marine Riser System Subject to Input Dead Zone and Extraneous Disturbances

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China Ocean Engineering 2024年第2期38卷 271-284页

作者： ZHOU Li wanG Guo-rong wan min School of Mechatronic Engineering Southwest Petroleum UniversityChengdu 610500China Energy Equipment Institute Southwest Petroleum UniversityChengdu 610500China National Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu 610500China

An observer-based adaptive backstepping boundary control is proposed for vibration control of flexible offshore riser systems with unknown nonlinear input dead zone and uncertain environmental *** control algorithm can update the control law online through real-time data to make the controller adapt to the environment and improve the control ***,based on the adaptive backstepping framework,virtual control laws and Lyapunov functions are designed for each *** direction interference observers are designed to track the timevarying boundary *** this basis,the inverse of the dead zone and linear state transformation are used to compensate for the original system and eliminate the adverse effects of the dead *** addition,the stability of the closed-loop system is proven by Lyapunov stability *** the system states are bounded,and the vibration offset of the riser converges to a small area of the initial ***,four examples of flexible marine risers are simulated in MATLAB to verify the effectiveness of the proposed controller.

关键词： adaptive backstepping control disturbance observer flexible marine riser input dead zone vibration control

THE STRUCTURAL FLOW IN PIPE CONTAINING POROUS MEDIUM SATURATED WITH POWER-LAW FLUID

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Journal of Hydrodynamics 2012年第1期24卷 138-144页

作者： ZHOU Xiao-jun YU min-chao School of Mechatronics-Engineering and Automation Shanghai UniversityShanghai 200072China

In this article,the method of volume averaging of flow in porous media and averaging theorem was employed to the Navier-Stokes *** total drag force per unit volume was considered as the bulk damping resistance due to the porous structure（i.e.,the Darcy resistance）and the resistance due to the inertia force（i.e.,the Forchheimer resistance）,then the Brinkman-Forchheimer extended Darcy model was obtained from average momentum *** structural flow in a pipe containing porous medium saturated with power law fluid was applied in the present study.A new theoretical analysis of fully developed non-Darcy flow in a pipe containing a fibrous medium saturated with power law fluid was *** the integration method,the boundary layer solutions were obtained for flow core velocity and its *** theoretical solutions were used to analyze the effects of the Darcy number and inertia parameter on the axial velocity profile in the porous medium pipe.

关键词： power-law fluid porous media volume averaging structural flow non-Darcy regime