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SIMULATION OF ThE MAGNETIZATION REVERSAL PROCESS OF RECTANGLE-ShAPED NiFe FILM ELEMENTS UNDER AN ORThOGONAL MAGNETIC FIELD

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Acta Metallurgica Sinica(English Letters) 2005年第5期18卷 642-646页

作者： w.L. zhang R.J. Tang w.X. zhang B. Peng h. C. Jiang h.w. zhang School of Microelectronics and Solid-state Electronics University of Electronic Science and Technology of China Chengdu 610054 China

The magnetization reversal process of nano-size rectangle-shaped NiFe film elements with different aspect ratios have been investigated under the orthogonally applied magnetic fields by micromagnetic simulation. Different magnetization reversal modes can appear depending on whether the bias field is applied or not. when there is no bias field, double “C” state is the initial reversal state. h.w.ver, when there is a bias field, “S” state is the starting mode. The larger the aspect ratio is, the larger the switching field is. But, when the aspect ratio is larger than 3, the increase of the switching field ceases. These results can provide useful information to the application of the patterned NiFe film with rectangular elements.

关键词： NiFe film element micromagnetics aspect ratio magnetization reversal,switching field

Distribution of Be in a Ti-Based Bulk Metallic Glass Composite Containing B-Ti

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Journal of Materials Science & Technology 2017年第7期33卷 708-711页

作者： L.zhang w.Q.Li Z.w.Zhu h.M.Fu h.Li Z.K.Li h.w.zhang A.M.wang h.F.zhang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences 110016 Shenyang China

In order to obtain a glassy matrix during quenching, Be is often selected as a constituent of the compositions of Ti/Zr-based bulk metallic glass composites（BMGCs）. The in situ formed β phase in Be-bearing BMGCs was reported to be Be-free. h.w.ver, a thorough investigation of the distribution of Be in BMGCs is still missing to date. In this work, the distribution of Be in a Ti_（47.5）Zr_（33）Cu_（5.8）Co_3Be_（12.5）（at.%） BMGC was studied by the secondary ion mass spectrometry（SIMS） and the electron energy loss spectroscopy（EELS）.It is found that Be almost totally dissolves in the glassy matrix, but a very weak intensity of Be in β phase is still detectable by SIMS, and the content of Be in β-Ti is estimated to be about 0.3 at.%. Based on the recently established two-phase quasi-equilibrium of BMGCs, the distinct solubility of Be in the glassy matrix and in β-Ti has been explained.

关键词： Bulk metallic glass(BMG) Metallic glass composite Beryllium Quasi-equilibrium

Identifi cation of QTLs for Drought Resistance of Maize Germination and Seedling Development

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分子植物育种 2007年第2期5卷 224-224页

作者： h.w. zhang 　Y.J. Liu　 Z.B. Tan　 Beijing DBN Agriculture Sci. ＆ Tech. Research Institute Beijing 100085 China

In most maize-growing areas yield reductions due to drought have been observed (Frova et al., 1999; Li et al., 2003; Ribaut et al., 1997; Sari-Gorla et al., 1999). Seed germination and early seedling growth is the

关键词：干旱玉米幼苗发芽

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

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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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

NUMERICAL MODELING OF DONGZhUANG RESERVOIR ON JING RIVER

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Journal of hydrodynamics 2001年第2期13卷 68-71页

作者： Yang, M. zhang, h.Y. zhang, J.h. zhang, h.w. Dept. 5 Beijing Univ. of Aero. and Astron. Beijing 100084 China

The Dongzhuang Reservoir will be constructed on the Jing River, which is laden with the highest sediment concentration in the world. The sediment problem is a key challenge for the reservoir design and management. This paper presents essential data, details of sediment scour and siltation calculated by the numerical modeling based on new fundamental equations. Calculated results prove that the reservoir could preserve long-term storage capacity with the operation was offered by the design department.

关键词： Flow of fluids Mathematical models Sediments Storage (materials)

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 sh.w. 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)

Approximation of Nearest Common Fixed Point of Nonexpansive Mappings in hilbert Spaces

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Acta Mathematica Sinica,English Series 2007年第10期23卷 1889-1896页

作者： Shi Sheng zhang h.w. JOSEPh LEE Chi Kin ChAN Department of Mathematics Yibin University Yibin 644007 P. R. China Department of Mathematics Sichuan University Chengdu 610064 P. R. China Department of Applied Mathematics The Hong Kong Polytechnic University Hung Horn Kowloon Hong Kong P. R. China

The purpose of this paper is to study the convergence problem of the iteration scheme xn＋l = λn＋1y ＋（1 - λn＋1）Tn＋1xn for a family of infinitely many nonexpansive mappings T1, T2,... in a hilbert space. It is proved that under suitable conditions this iteration scheme converges strongly to the nearest common fixed point of this family of nonexpansive mappings. The results presented in this paper extend and improve some recent results.

关键词： common fixed point family of nonexpansive mappings nearest point projection iterative scheme