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Journal of Energy Chemistry 2025年第1期100卷 245-258页

作者： Gaeun Lee Yong Nam Ahn Seongjoon So Chanwoo park Jong-Seong Bae Taehyun park Il Tae Kim Jaehyun hur School of Chemical Biological and Battery Engineering Gachon University Seongnam Busan Center Korea Basic Science Institute

Aqueous Zn-ion batteries （AZIBs） have received considerable attention owing to their various advantages such as safety,low cost,simple battery assembly conditions,and high ionic ***,they still suffer from serious problems,including uncontrollable dendrite growth,corrosion,hydrogen evolution reaction （hER） from water decomposition,electrode passivation,and unexpected *** creation of a uniform artificial nanocrystal layer on the Zn anode surface is a promising strategy for resolving these ***,we propose the use of a perovskite CaTiO3（CTO） protective layer on Zn（CTO@Zn） as a promising approach for improving the performance of *** CTO artificial layer provides an efficient pathway for Zn ion diffusion towards the Zn metal because of the high dielectric constant （εr=180） and ferroelectric characteristics that enable the alignment of dipole moments and redistribute the Zn2+ions in the CTO *** avoiding the direct contact of the Zn anode with the electrolyte solution,the uneven dendrite growth,corrosion,parasitic side reactions,and hER are mitigated,while CTO retains its mechanical and chemical robustness during ***,CTO@Zn demonstrates an improved lifespan in a symmetric cell configuration compared with bare ***@Zn shows steady overpotential （～68 m V） for 1500 h at 1 mA cm-2/0.5 mA h cm-2,excelling bare ***,when paired with the V2O5-C cathode,the CTO@Zn//V2O5-C full battery delivers 148.4 mA h g-1（based on the mass of the cathode） after 300 *** study provides new insights into Zn metal anodes and the development of high-performance AZIBs.

关键词： Perovskite

Scalable Ir‑Doped NiFe_(2)O_(4)/TiO_(2)heterojunction Anode for Decentralized Saline Wastewater Treatment and h_(2)Production

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Nano-Micro Letters 2025年第3期17卷 1-18页

作者： Sukhwa hong Jiseon Kim Jaebeom park Sunmi Im Michael R.hoffmann Kangwoo Cho Division of Environmental Science and Engineering Pohang University of Science and Technology(POSTECH)Pohang 790−784Korea Linde Laboratory California Institute of TechnologyPasadenaCA 91125USA Institute for Convergence Research and Education in Advanced Technology(I‑CREATE) Yonsei University International CampusIncheon 21983Republic of Korea

Wastewater electrolysis cells(WECs)for decentralized wastewater treatment/reuse coupled with h_(2)production can reduce the carbon footprint associated with transportation of water,waste,and energy *** study reports Ir-doped NiFe_(2)O_(4)(NFI,~5 at%Ir)spinel layer with TiO_(2)overlayer(NFI/TiO_(2)),as a scalable heterojunction anode for direct electrolysis of wastewater with circumneutral ph in a single-compartment *** dilute(0.1 M)NaCl solutions,the NFI/TiO_(2)marks superior activity and selectivity for chlorine evolution reaction,outperforming the benchmark IrO_(2).Robust operation in near-neutral ph was *** including operando X-ray absorption spectroscopy unveiled crucial roles of TiO_(2) which serves both as the primary site for Cl−chemisorption and a protective layer for NFI as an ohmic *** electrolysis of Nh4+-laden synthetic wastewater demonstrated that NFI/TiO_(2)not only achieves quasi-stoichiometric Nh_(4)^(+)-to-N_(2)conversion,but also enhances h_(2)generation efficiency with minimal competing reactions such as reduction of dissolved oxygen and reactive *** scaled-up WEC with NFI/TiO_(2)was demonstrated for electrolysis of toilet wastewater.

关键词： Wastewater electrolysis cell Ir-doped NiFe_(2)O_(4) Reactive chlorine species Decentralized h_(2)production On-site wastewater treatment

Microstructure and creep properties of Mg-4Al-2Sn-1(Ca,Sr) alloys

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Transactions of Nonferrous Metals Society of China 2010年第7期20卷 1184-1191页

作者： B.h.KIM K.C.park Y.h.park I.M.park Department of Material Science and Engineering Pusan National UniversitySan 30 Jangjeon-dongGeumjeong-guBusan 609-735Korea

The effects of Ca and Sr addition on the microstructure and creep properties of Mg-4Al-2Sn alloys were examined. Tensile tests at 25 ℃ and 200 ℃ and creep tests at 150 ℃ and 200 ℃ were carried out to estimate the room temperature and high temperature mechanical properties of these alloys. The microstrueture of the Mg-4Al-2Sn alloy showed dendritic a-Mg, Mg17Al12 and Mg2Sn phases. The latter two phases precipitated along the grain boundaries. The addition of Ca and Sr resulted in the formation of ternary CaMgSn and SrMgSn phases within the grain. The grain size was reduced slightly with the addition of Sr and Ca. The tensile strength was decreased by the addition of Ca and Sr at room temperature. however, the high temperature tensile strength was increased. The creep strength was improved by the addition of Ca and Sr.

关键词： magnesium alloys Ca Sr void initiation mechanical properties creep mechanism

Evaluation of microstructure and mechanical properties of Mg-xCe-0.5Zn alloys by nano-indentation

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Transactions of Nonferrous Metals Society of China 2010年第7期20卷 1240-1243页

作者： K.C.park B.h.KIM Y.h.park I.M.park Department of Material Science and Engineering Pusan National UniversitySan 30 Jangjeon-dongGeumjeong-guBusan 609-735Korea

The microstructure and mechanical properties of Mg-xCe-0.5Zn （x=0.5, 1.5, 2.5, molar fraction, %） alloys were examined using a nano-indentation technique. The alloys were fabricated using a vacuum induction melting method under an argon atmosphere The microstruetures of Mg-xCe-0.5Zn alloys mainly consist ofa-Mg and eutectic Mg12Ce phase. The volume fraction and size of the eutectic Mgl2Ce phase increase with increasing Ce contents. Nano-indentation test results show that the indentation hardness and elastic modulus of the eutectic Mg12Ce phase are higher than those of the a-Mg matrix. In addition, the mean indentation hardness and elastic modulus of the Mg-xCe-0.5Zn alloys increase with the Ce addition amount increasing.

关键词： Mg alloys Mg-Ce-Zn rare earth microstructure mechanical properties nano-indentation

Adaptive Functional Projective Lag Synch.onization of a hyperchaotic Rossler System

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Chinese Physics Letters 2009年第9期26卷 69-72页

作者： Tae h. Lee Ju h. park Nonlinear Dynamics Group Department of Electrical Engineering Yeungnam University 214-1 Dae-Dong Kyongsan 712-749 Republic of Korea

We explain the functional projective lag synch.onization of a hyperchaotic Rossler system with four unknown parameters, where the output of the master system lags behind the output of the slave system proportionally. Based on Lyapunov stability theory, an active control method and adaptive control law are employed to make the states of two hyperchaotic Rossler systems asymptotically synch.onized. Finally, some numerical examples are provided to show the effectiveness of our results.

关键词： No English Keyword

Redox Charge Transfer Kinetics and Reversibility of VO_(2) in Aqueous and Non-Aqueous Electrolytes of Na-Ion Storage

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Energy & Environmental Materials 2022年第4期5卷 1222-1228页

作者： Sul Ki park Kang ho Shin Puritut Nakhanivej harpalsinh h.Rana ho Seok park School of Chemical Engineering College of EngineeringSungkyunkwan University2066Seobu-roJangan-guSuwon-si Gyeonggi-do 440-746Republic of Korea Department of Engineering University of CambridgeCambridge CB30FSUK Department of health Sciences and Technology Samsung Advanced Institute for Health Sciences and Technology(SAIHST)Sungkyunkwan University2066SeoburoJangan-guSuwon 440-746South Korea SKKU Advanced Institute of Nano Technology(SAINT) Sungkyunkwan University2066SeoburoJangan-guSuwon 440-746South Korea

The deep understanding about the electrochemical behavior of the nanostructured electrode in electrolytes provides crucial insights for the rational design of electrode for sodium(Na)-ion storage system(NIS).here,we report redox charge transfer kinetics and reversibility of VO_(2)(B) nanorod electrodes in both aqueous and organic electrolytes for *** assynthesized VO_(2)(B) nanorods show the reversible redox reaction with the higher specific and rate capacitances at high current density in aqueous electrolytes than in organic ***-dependent impedance measurements demonstrate the more facile interfacial charge transfer of Na ions into VO_(2)(B) nanorods in aqueous *** reversible evolution in oxidation state and chemical composition of VO_(2)(B) nanorods is observed in aqueous electrolytes,as confirmed by ex situ XRD and ex situ X-ray photoelectron spectroscopy *** by the facile and reversible pseudocapacitive feature,the electrochemical performances of VO_(2)(B) nanorods are further improved by constructing the hierarchical structure of the reduced graphene oxide-VO_(2) composite for aqueous Na+ion storage.

关键词： aqueous electrolyte energy storage mechanism hierarchical structure nanorod sodium ion storage

Optimal design of V-type ultrasonic motor

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Journal of Central South University 2010年第6期17卷 1247-1250页

作者： JEONG S S park C h park T G School of Mechatronics Changwon National UniversityChangwon 641773Korea

V-type ultrasonic linear motor fabricated using a simple punching technique was proposed to utilize as an actuator of small precision *** stator of the motor is composed of a thin elastic body and four ceramics attached to the upper and bottom areas of the *** ceramics have each direction of *** two harmonic voltages with a 90° phase difference are applied to the ceramics,symmetric and anti-symmetric displacements will generate at the tip to produce an elliptical motion.A finite element analysis(ATILA) was conducted to simulate the motion pattern for the contact tip of the *** develop a model that generates the maximum displacement at contact tip,the FEM program was used for various *** addition,an optimal model was chosen by considering the magnitude and shape of the displacement according to changes in *** maximum elliptical displacement is shown by W2L11 model,which has a ratio of ceramic width to length of 1:***,the displacement of the contact tip is reduced by the bucking phenomenon if the ratio is larger than 1:6.

关键词： ultrasonic motor piezo-actuator finite element method optimal design elliptical motion

Incremental forming of free surface with magnesium alloy AZ31 sheet at warm temperatures

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中国有色金属学会会刊：英文版 2008年第A01期18卷 165-169页

作者： Y.h.JI J.J.park Department of Mechanical and System Design Engineering Hongik University

The formabilityof AZ31 sheet begins to increase drastically at 150℃.The incremental forming technique was thus applied to AZ31 sheet at 150℃to utilize the formability to its fullest capacity at the lowest possible temperature for forming applications.A surface scanning technique was used followed by the tool path generation to incrementally form an egg *** thorough examination of various tool paths,the surface was most successfully produced by forming an intermediate shape followed by a series of tool *** scale stickers were devised to improve the accuracy in the measurement of grid deformation.

关键词：金属材料数控成形加工 AZ31镁合金板材

Deposition of Nano-Scaled Coatings Using Inductively Coupled Plasma

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Journal of Rare Earths 2004年第z2期22卷 153-156页

作者： D h Jung B park J J Lee School of Materials Science and Engineering College of EngineeringSeoul National UniversitySeoul 151-744Korea School of Materials Science and EngineeringCollege of EngineeringSeoul National UniversitySeoul 151-744Korea School of Materials Science and EngineeringCollege of EngineeringSeoul National UniversitySeoul 151-744Korea

Nano-scaled Ti-B-N coatings could be produced by inductively coupled plasma (ICP) assisted magnetron spurtering. The properties and microstructure of the coating can be changed drastically by applying ICP to conventional magnetron sputtering. In this work, an internal type rf ICP process is used. The core of this technology is the efficient production and control of self-depositing ions and reactive gas ions by an induced electric field. Ti-B-N coatings were prepared by using a TiB2 target and a gas mixture of N2 and Ar at 200 ℃ and a pressure of 60 mTorr. In addition to ICP, the effect of the substrate bias voltage on the structure and properties of the coating was investigated. By applying ICP and a bias voltage to the substrate the hardness of the Ti-B-N coating is increased by more than 75 GPa, as a result of enhanced ionization in the plasma. The Ti-B-N coating, which has the highest hardness, shows the best surface uniformity and a very dense structure with a grain size of 3 nm. This sample also shows a high crystallinity compared to the coating prepared using other deposition parameters.

关键词： nano-scaled coatings industively conpled plasma

hot Data Identification with Multiple Bloom Filters： Block-Level Decision vs I/O Request-Level Decision

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Journal of Computer Science & Technology 2018年第1期33卷 79-97页

作者： Dongchul park Weiping he h. C. Du Division of Computer and Electronic Systems Engineering Hankuk University of Foreign Studies Gyeonggi-do 17035 Korea Intel Corporation Hillsboro OR 97124 U.S.A. Dell Storage Eden Prairie MN 55344 U.S.A. Department of Computer Science and Engineering University of Minnesota-Twin Cities Minneapolis MN 55455 U.S.A.

hot data identification is crucial for many applications though few investigations have examined the subject. All existing studies focus almost exclusively on frequency. however, effectively identifying hot data requires equally considering recency and frequency. Moreover, previous studies make hot data decisions at the data block level. Such a fine-grained decision fits particularly well for flash-based storage because its random access achieves performance comparable with its sequential access. however, hard disk drives （hDDs） have a significant performance disparity between sequential and random access. Therefore, unlike flash-based storage, exploiting asymmetric hDD access performance requires making a coarse-grained decision. This paper proposes a novel hot data identification scheme adopting multiple bloom filters to efficiently characterize recency as well as frequency. Consequently, it not only consumes 50% less memory and up to 58% less computational overhead, but also lowers false identification rates up to 65% compared with a state-of-the-art scheme. Moreover, we apply the scheme to a next generation hDD technology, i.e., Shingled Magnetic Recording （SMR）, to verify its effectiveness. For this, we design a new hot data identification based SMR drive with a coarse-grained decision. The experiments demonstrate the importance and benefits of accurate hot data identification, thereby improving the proposed SMR drive performance by up to 42%.

关键词： hot data bloom filter shingled magnetic recording (SMR)