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Acta Mechanica Solida Sinica 2018年第1期31卷 108-126页

作者： Z.N.Li Y.X.hao W.zhang j.h.zhang College of Mechanical Engineering Beijing Information Science and Technology University College of Mechanical Engineering Beijing University of Technology

In this paper, the nonlinear transient dynamic response of functionally graded material （FGM） sandwich doubly curved shell with homogenous isotropic material core and functionally graded face sheet is analyzed using a new displacement field on the basis of Reddy＇s third-order shear theory for the first time. The equivalent material properties for the FGM face sheet are assumed to obey the rule of simple power law function in the thickness direction. Based on Reddy＇s theory of higher shear deformation, a new displacement field is developed by introducing the secant function into transverse displacement. Four coupled nonlinear differential equations are obtained by applying hamilton＇s principle and Galerkin method. It is assumed that the FGM sandwich doubly curved shell is subjected to step loading, air-blast loading, triangular loading, and sinusoidal loading, respectively. On the basis of double-precision variable- coefficient ordinary differential equation solver, a new program code in FORTRAN software is developed to solve the nonlinear transient dynamics of the system. The influences of core thickness, volume fraction, core-to-face sheet thickness ratio, width-to-thickness ratio and blast type on the transient response of the shell are discussed in detail through numerical simulation.

关键词： New displacement fields Functionally graded materials Sandwich doubly curvedshell Blast load Nonlinear transient response

Effects of Terracing and Agroforestry on Soil and Water Loss in hilly Areas of the Sichuan Basin, China

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journal of Mountain Science 2008年第3期5卷 241-248页

作者： j.h. zhang Z.A. SU G.C. LIU Key Laboratory of Mountain hazards and Earth Surface Processes Chinese Academy of Sciences 610041 China Institute of Mountain hazards and Environment Chinese Academy of Sciences ＆Ministry of Water Conservancy Chengdu 610041 China The Graduate School of the Chinese Academy of Sciences Beijing 100049 China

Soil erosion in hilly areas of the Sichuan Basin is a serious concern over sustainable crop production and sound ecosystem. A 3-year experiment was conducted using the method of runoff plots to examine the effects of terracing and agroforestry in farmland systems on soil and water conservation of slope fields in the hilly areas in jianyang County, Sichuan Province, Southwestern China. A power function (Y = aXb) can statistically describe the relationship between water runoff (Y) and rainfall (X). The regression equation for the treatment of sloping terraces with crops (Plot 2) is remarkably different from that for the treatment of sloping terraces with grasses and trees (Plot 1) and the conventional up- and down-slope crop system (Plot 3) regarding equation coefficients, while regression equations are similar between Plot 1 and Plot 3. Water runoff amount and runoff coefficient of slope fields increased by 21.5～41.0 % and 27.5～69.7 % respectively, compared to those of sloping terraces, suggesting that terracing notably reduced the water runoff in the field. In the case of sloping terraces, lower amount of water runoff was observed on sloping terraces with crops than on sloping terraces with grasses and trees. Sediment yields on the slope fields in the normal year of rainfall distribution were notably higher (34.41～331.67 % and 37.06～403.44 % for Plot 1 and Plot 2, respectively) than those on sloping terraces, implying that terracing also plays a significant role in the reduction in soil erosion. It is suggested that terracing with crops is significantly effective for soil and water conservation in cultivatedfarmland, while the conventional practice of up- and down- slope cultivation creates high rates of water runoff and soil sediment transport. Terracing with grasses and fruit trees shows a less reduction in water runoff than terracing with crops, which was observed in the 3-year experiments.

关键词： Agroforestry sediment transport runoff sloping terrace soil and water conservation

The Kinetics of Reorientation of Multi-Variants under the Continuous Tensile Stress: Phase-Field Simulation

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The Kinetics of Reorientation of Multi-Variants under the Co...

DESIGN AND PROPERTIES OF A FUNCTIONALLY GRADIENT CERAMIC TOOL MATERIAL

中国材料大会2012

作者： j.F. Wan j.h. zhang Y.h. Rong School of Materials Science and Engineering Shanghai Jiao Tong University

ISBN: (纸本)9783037856093

The kinetics of martensitic variant reorientation as well as the evolutional pathway under the continuous tensile stress in NiMnGa alloys has been investigated by using Phase-field method. The simulated results revealed that the final structures and the pathway of evolutioncan be determined by the different external stress and there existed a critical stress to obtain the single variant. The related kinetics and the mechanism of the structural conversion were proposed to explain the inner physical nature. The pseudo-elasticity related to the structural conversion was also investigated. The mechanism of the motion for interfacial step associated with the nucleation and growth of one variant in another variant at the twin boundary was discussed.

关键词： Kinetics Reorientation Variant Tensile stress Phase-field simulation.

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Acta Metallurgica Sinica(English Letters) 1999年第5期12卷 1054-1058页

作者： j. Zhao,X. Ai, j.h. zhang, j.X. Deng and C.Z. huang Department of Mechanical Engineering, Shandong University of Technology, jinan 250061,China

Based on the analyses of the severity of cutting process as well as the failure mechanisms of ceramic tools, a model for designing functionally gradient ceramic tool materials with symmetrical distribution is presented, by which a Al 2O 3/(W,Ti)C ceramic tool material FG 2 was developed. Multi objective optimization method was employed in designing the compositional distribution of this ceramic tool material. The results of both continuous and intermittent cutting tests are indicative of the much better cutting behavior of the functionally gradient ceramic tool FG 2 than that of the common ceramic tool SG 4.

关键词： functionally gradient materials materials design compositional distribution ceramic tool

The optimal control theory——a scientific approach to fundamentally solving control problems

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Science China(Information Sciences) 2025年第1期68卷 389-391页

作者： huanshui zhang School of Electrical and Automation Engineering Shandong University of Science and Technology School of Control Science and Engineering Shandong University

The maximum principle has bridged mathematical optimization to optimal control,ushering in significant developments and refinements in optimal control theory,notably during the 1960s with the advent of linear quadratic (LQ)control and linear quadratic estimation (LQE).This progression propelled optimal control theory into further advancements,encompassing stochastic control,robust/h-infinity control,model predictive control (MPC),networked control,and reinforcement learning *** control,established upon a rigorous mathematical foundation,extends static optimization theory to dynamic systems,exhibiting scientific essence,unity,and ***,since its inception,optimal control theory has served as an indispensable core role across all control-related domains,including communication-constrained control in networked systems,consensus control,cooperative control,and reinforcement learning control.

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Sleep as a window to understand and regulate Alzheimer's disease:emerging roles of thalamic reticular nucleus

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Neural Regeneration Research 2025年第6期20卷 1711-1712页

作者： haoqi Sun Shiqian Shen Robert j.Thomas M.Brandon Westover Can zhang Department of Neurology Beth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Center for Translational Pain Research Department of AnesthesiaCritical Care and Pain MedicineMassachusetis General HospitalHarvard Medical SchoolBostonMAUSA Division of Pulmonary Critical Care and Sleep MedicineDepartment of MedicineBeth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Genetics and Aging Research Unit McCance Center for Brain HealthMass General Institute for Neurodegenerative DiseaseDepartment of NeurologyMassachusetts General HospitalHarvard Medical SchoolBostonMAUSA

Introduction:Alzheimer 's disease(AD) is a common neurodegenerative disorder and the primary cause of dementia. Considerable evidence supports the “amyloid hypothesis,” stating that the pathogenesis of AD is primarily caused by the deposition of amyloid-β(Aβ), which drives tau phosphorylation, neuroinflammation, and neurodegeneration in the brain. The amyloid hypothesis is strengthened by the significant and moderate benefit of lecanemab, a humanized antibody through an anti-amyloid mechanism,showing slowed clinical decline(van Dyck et al.,2023). The recent positive results of anti-amyloid trials have brought back focus on the amyloid hypothesis through biochemical, genetic, and pharmacological approaches(zhang, 2023).

关键词： Alzheimer inflammation hypothesis

A functional tacrolimus-releasing nerve wrap for enhancing nerve regeneration following surgical nerve repair

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Neural Regeneration Research 2025年第1期20卷 291-304页

作者： Simeon C.Daeschler Katelyn j.W.So Konstantin Feinberg Marina Manoraj jenny Cheung jennifer zhang Kaveh Mirmoeini jPaul Santerre Tessa Gordon Gregory hBorschel SickKids Research Institute Neuroscience and Mental Health ProgramTorontoONCanada Institute of Biomaterials and Biomedical Engineering University of TorontoTorontoONCanada Indiana University School of Medicine IndianapolisINUSA Division of Plastic and Reconstructive Surgery the Hospital for Sick ChildrenTorontoONCanada Translational Biology and Engineering Program Ted Rogers Centre for Heart ResearchInstitute of Biomedical EngineeringFaculty of DentistryUniversity of TorontoTorontoONCanada

Axonal regeneration following surgical nerve repair is slow and often incomplete,resulting in poor functional recovery which sometimes contributes to lifelong ***,there are no FDA-approved therapies available to promote nerve *** accelerates axonal regeneration,but systemic side effects presently outweigh its potential benefits for peripheral nerve *** authors describe herein a biodegradable polyurethane-based drug delivery system for the sustained local release of tacrolimus at the nerve repair site,with suitable properties for scalable production and clinical application,aiming to promote nerve regeneration and functional recovery with minimal systemic drug *** is encapsulated into co-axially electrospun polycarbonate-urethane nanofibers to generate an implantable nerve wrap that releases therapeutic doses of bioactive tacrolimus over 31 *** and drug loading are adjustable for applications in small and large caliber nerves,and the wrap degrades within 120 days into biocompatible *** released from the nerve wrap promotes axon elongation in vitro and accelerates nerve regeneration and functional recovery in preclinical nerve repair models while off-target systemic drug exposure is reduced by 80%compared with systemic *** its surgical suitability and preclinical efficacy and safety,this system may provide a readily translatable approach to support axonal regeneration and recovery in patients undergoing nerve surgery.

关键词： biodegradable local drug delivery nerve injury nerve regeneration nerve wrap tacrolimus

Numerical Study of Flow and heat Transfer Characteristics of Shell-and-Tube Molten Salt Electric heater with Circularly Perforated Baffles

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journal of Thermal Science 2025年第1期34卷 24-33页

作者： LIN Yongjie zhang Cancan WU Yuting zhang Yi LU Yuanwei Key Laboratory of heat Transfer and Energy Conversion National User-Side Energy Storage Innovation Research and Development CenterBeijing University of Technology

Numerical simulations of the flow and heat transfer characteristics of four shell-and-tube molten salt electric heaters with different perforation rates was ***-and-tube electric heaters have the same geometry and tube arrangement,and all of them use single segmental baffles,but there exist four different baffle openings（φ）,i.e.,0%,2.52%,4.06%,and 6.31%.The results indicated that the reasonable baffle opening could significantly reduce the shell-side pressure drop,effectively decreasing the shell-side flow dead zone *** can eliminate the local high-temperature phenomenon on the surface of electric heating tubes,but the heat transfer coefficient is slightly *** perforated schemes significantly reduce shell-side pressure drop compared to the baseline solution without open *** particular,the φ=6.31% scheme exhibits the optimal performance among all the schemes,with a maximum reduction of up to 50.50% in shell-side pressure drop relative to the unopened holes *** heat transfer coefficient is the highest for φ=0%,exhibiting a range of5.26% to 5.73%,5.14% to 5.99%,and 7.31% to 8.54% higher than φ=2.52%,4.06%,and 6.31%,respectively,within the calculated *** composite index h/（Δp）1/3was higher for all open-hole solutions than that for the unopened-hole *** best overall performance was for φ=6.31%,which improved the composite index by15.29% to 17.18% over the unopened-hole solution.

关键词： molten salt electric heater perforated baffles heat transfer

Nano high-entropy oxide cathode with enhanced stability for direct borohydride fuel cells

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journal of Energy Chemistry 2025年第1期100卷 309-316页

作者： Lei zhang Lingfeng Kuang Lianke zhang Wen Chu haiying Qin jing zhang junjing he hualiang Ni hongzhong Chi New Energy Materials Research Center College of Materials and Environmental Engineering Hangzhou Dianzi University School of Materials Science and Engineering Zhejiang University Key Laboratory of MEMS of Ministry of Education School of Integrated Circuits Southeast University

high-entropy materials have become high-activity electrocatalysis owing to their high-entropy effect and multiple active ***,we synthesize a series of carbon-supported nano high-entropy oxides（hEOs/C）,specifically （PtFeCoNiCu）O/C,using a carbothermal shock （CTS） method for application as a cathode catalyst in direct borohydride fuel cells （DBFCs）.The microstructure of the prepared catalysts was characterized by X-ray photoelectron spectroscopy,X-ray absorption fine structure,and transmission electron *** prepared （PtFeCoNiCu）O/C,with particle sizes ranging from 2 to 4 nm,demonstrates 3.94 transferred electrons towards the oxygen reduction reaction in an alkaline environment,resulting in a minimal h2O2yield of 2.6%.Additionally,it exhibits a Tafel slope of 61 mV dec-1,surpassing that of commercial Pt/C (82 mV dec-1).Furthermore,after 40,000 cycles of cyclic voltammetry（CV） testing,the half-wave potential of （PtFeCoNiCu）O/C shows a positive shift of 3 mV,with no notable decline in the limiting current *** （PtFeCoNiCu）O/C is used as a cathode catalyst in DBFCs,the DBFC achieves a maximum power density of 441 mW cm-2at 60°C and sustains a cell voltage of approximately 0.73 V after 52 h at 30°*** findings confirm that hEO/C is a promising cathode catalyst for DBFCs.

关键词： Direct borohydride fuel cells (DBFC)

Dielectric-ion-conductive ZnNb2O6 layer enabling rapid desolvation and diffusion for dendrite-free Zn metal batteries

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journal of Energy Chemistry 2025年第1期100卷 693-701页

作者： haifeng Yang jian Wang Panpan zhang Xiaomin Cheng Qinghua Guan jing Dong Bixian Chen Lujie jia jing zhang Yongzheng zhang Yunjian Liu hongzhen Lin School of Materials Science and Engineering Jiangsu University i-Lab & CAS Key Laboratory of Nanophotonic Materials and Devices Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences helmholtz Institute Ulm (hIU) Karlsruhe Institute of Technology (KIT) School of Materials Science and Engineering Xi'an University of Technology State Key Laboratory of Chemical Engineering East China University of Science and Technology

Rechargeable aqueous zinc-metal batteries （AZMBs） are promising candidates for large-scale energy storage systems due to their low cost and high ***,their performance and sustainability are significantly hindered by the sluggish desolvation kinetics at the electrode/electrolyte interface and the corresponding hydrogen evolution reaction where active water molecules tightly participate in the Zn（h2O）62+solvation ***,learnt from self-generated solid electrolyte interphase （SEI） in anodes,the dielectric but ion-conductive zinc niobate nanoparticles artificial layer is constructed on metallic Zn surface （ZNB@Zn）,acting as a rapid desolvation *** zincophilic and dielectric-conductive properties of ZNB layer accelerate interfacial desolvation/diffusion and suppress surface corrosion or dendrite formation,achieving uniform Zn plating/stripping behavior,as confirmed by electronic/optical microscopies and interface spectroscopical measurements together with theoretical ***,the as-prepared ZNB@Zn electrode exhibits excellent cycling stability of over 2000 h and robust reversibility （99.54%） even under high current density and depth of discharge ***,the assembled ZNB@Zn-based full cell displays high capacity-retention rate of 80.21%after 3000 cycles at 5 A g-1and outstanding rate performance up to 10 A *** large-areal pouch cell is stabilized for hundreds of cycles,highlighting the bright prospects of the dielectric but ion-conductive layer in further application of AZMBs.

关键词： Zn metal battery Dielectric artificial layer Rapid ion diffusion Zincophilic diffusion Active water inhibition