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Prominent cycling reversibility and kinetics enabled by CaTiO3 protective layer on Zn metal for aqueous Zn-ion batteries

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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： Artificial layer Dielectric constant Zn metal anode Zinc aqueous battery

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

Network Log-based SSH brute-Force Attack Detection Model

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Computers, Materials & Continua 2021年第7期68卷 887-901页

作者： jeonghoon park jinsu Kim b.b.Gupta Namje park Department of Convergence Information Security Graduate SchoolJeju National UniversityJeju63243Korea Department of Computer Engineering National Institute of Technology KurukshetraKurukshetra136119India

The rapid advancement of IT technology has enabled the quick discovery,sharing and collection of quality information,but has also increased cyberattacks at a fast pace at the same *** exists no means to block these cyberattacks completely,and all security policies need to consider the possibility of external ***,it is crucial to reduce external attacks through preventative *** general,since routers located in the upper part of a firewall can hardly be protected by security systems,they are exposed to numerous unblocked *** block unnecessary services and accept necessary ones while taking appropriate measures to reduce vulnerability,block unauthorized access,and generate relevant *** logs created through unauthorized access are caused by SSH brute-force attacks,and therefore IP data of the attack can be collected through the *** paper proposes a model to detect SSH brute-force attacks through their logs,collect their IP address,and control access from that IP *** this paper,we present a model that extracts and fragments the specific data required from the packets of collected routers in order to detect indiscriminate SSH input *** do so,the model multiplies a user’s access records in each packet by weights and adds them to the blacklist according to a final calculated result *** addition,the model can specify the internal IP of an attack attempt and defend against the first 29 destination IP addresses attempting the attack.

关键词： SSH brute-force attack ELK Stack IT infra log access control

Heavy Metals in brown Rice(Oryza sativa L.) and Soil After Long-Term Irrigation of Wastewater Discharged from Domestic Sewage Treatment Plants

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Pedosphere 2011年第5期21卷 621-627页

作者： b.Y.CHUNG C.H.SONG b.j.park j.Y.CHO Advanced Radiation Technology Institute Korea Atomic Energy Research Institute(KAERI) Korea Testing & Research Institute(KTR) Department of Horticultural Science Chungbuk National University Department of bio-environmental Chemistry Chonbuk National University

A pot experiment was conducted in a plastic film house to evaluate the translocation and uptake of heavy metals(Pb,Cd,Cu,and Zn) into brown rice(Oryza sativa L.) and the heavy metals residues in soils which had previously been irrigated with domestic wastewater for a long time(3 years).The range of Pb,Cd,Cu,and Zn was 5.10 ± 0.01,0.105 ± 0.017,5.76 ± 0.42,and 23.56 ± 1.40 mg kg-1,respectively in the domestic wastewater-irrigated soil,and 0.370 ± 0.006,0.011 ± 0.001,0.340 ± 0.04,and 2.05 ± 0.18 mg kg-1,respectively,in the domestic wastewater-irrigated brown *** results indicated that application of domestic wastewater to arable land slightly increased the levels of Pb,Cd,Cu,and Zn in soil and brown rice(P brown rice were lower than the recommended tolerable levels proposed by the joint FAO/WHO Expert Committee on Food ***,the continuous monitoring and pollution control of hazardous materials from domestic wastewater are needed in order to prevent excessive build-up of heavy metals in the food chain.

关键词： accumulation domestic wastewater ground water irrigation P2O5 total N

Understanding pediatric surgical needs in North Korea: a modeling analysis

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World journal of Pediatric Surgery 2024年第1期7卷 47-53页

作者： Phillip j Hsu Sangchul Yoon Kee b park University of Michigan Ann ArborMichiganUSA Department of Global Health and Social Medicine Harvard Medical SchoolBostonMassachusettsUSA Department of Medical Humanitiesand Social Sciences Yonsei University SeoulSouth Korea

background Sixty-five percent of children worldwide lack access to surgical care,the majority of whom live in low-income and middle-income countries(LMiCs).Developing surgical infrastructure requires information on surgical need;however,this information is often limited in *** Korea(Democratic People's Republic of Korea,DPRK)has a low amount of publicly available ***,we analyzed available modeled data to understand the causes of pediatric deaths due to conditions treatable with surgery in *** We used World bank data and models from the Institute for Health Metrics and Evaluation to identify causes of pediatric deaths affecting pediatric patients(agebetween DPRK and countries with similar economic *** between 1990 and 2019,the number of overall pediatric deaths has *** 2019,32.2%of allpediatric deaths in DPRK were caused by surgical *** leading categories of surgical conditions were injuries(53.9%),congenital conditions(34.2%),tumors(8.8%),and abdominal conditions(3.2%).DPRK has a lower relative rate of pediatric deaths compared with other LMICs with similar gross domestic product per ***,it has a higher relative rate of pediatric deaths due to conditions requiring treatment with *** injuries contribute significantly to the high rate of pediatric deaths in *** Although DPRK may be allocating overall resources toward pediatric healthcare more efficiently than economic peers,DPRK may benefit from improvement in pediatric surgical *** availability of data and close international collaboration could be potential solutions to bridge this gap.

关键词： pediatric surgical injuries

HYERS—ULAM—RASSIAS STAbILITY OF QUADRATIC FUNCTIONAL EQUATIONS IN bANACH MODULES OVER A C^＊—ALGEbRA

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Chinese Annals of Mathematics,Series b 2003年第2期24卷 261-266页

作者： C. park j. park j. SHIN Department of Mathematics Chungnam National University DaeJeon 305-764 South Korea.Department of Mathematics Chungnam National University DaeJeon 305-764 South Korea.Department of Mathematics Chungnam National University DaeJeon 305-764 South Korea.

The authors prove the Hyers-Ulam-Rassias stability of the quadratic mapping in banachmodules over a unital C*-algebra, and prove the Hyers-Ulam-Rassias stability of the quadraticmapping in banach modules over a unital... 详细信息

关键词： Stability b-quadratic Functional equation banach module over banach algebra

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

Effect of 1Al addition on deformation behavior of Mg

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journal of Magnesium and Alloys 2021年第2期9卷 489-498页

作者： ji Hyun Hwang A.Zargaran Gyeongbae park O.Lee b.-j.Lee Nack j.Kim Center for Advanced Aerospace Materials Pohang University of Science and Technology(POSTECH)PohangSouth Korea

Deformation behavior of 1 Al containing Mg alloy has been investigated in the present *** annealing,the Mg-1 Al alloy shows a typical basal *** compared to the pure Mg having a similar texture and grain size,the Mg-1 Al alloy shows much higher strength and larger *** trace analyses of the tensile strained specimens show that non-basal slips such as pyramidal I and II slips can be easily activated at an early stage of deformation in the Mg-1 Al alloy and the grains in the Mg-1 Al alloy are seen to accommodate a larger degree of deformation than those in the pure Mg at a given *** increasing tensile strain,however,there is a strain localization along the initially formed slip lines of non-basal slips,forming surface steps without activating multiple slip lines.

关键词： Deformation behavior Slip trace analysis Non-basal slip Strain localization Ductility

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