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journal of Energy Chemistry 2025年第1期100卷 180-191页

作者： Byeongchan Ahn Sua jo jonggeol Na j.jay Liu Young-ju kim Wangyun Won Department of Chemical and Biological Engineering Korea University Department of Chemical Engineering (Integrated process) Kyung Hee University Department of Chemical Engineering and Materials Science Ewha Womans University Department of Chemical Engineering Pukyong National University Resources Engineering Plant Research Department Korea Institute of Geoscience and Mineral Resources

Lignocellulosic biomass is one of the viable solutions to alleviate the global warming. However, the limited utilization of biomass majorly focused on cellulose and hemicellulose restricts the economic and environmental feasibilities. To cope with this issue, we proposed an integrated process of co-producing 1,6-hexanediol（1,6-HDO） with tetrahydrofuran and adipic acid from biomass, referred to as Strategy A. To compare the impacts of lignin upgrading and feedstock, Strategy B, which co-produces tetrahydrofuran alone, and Strategy C, which is the traditional route to produce 1,6-HDO from fossil fuels, were used. Heat networks are also designed to reduce operating costs and indirect carbon emissions due to energy consumption, saving 87% and 83% of the heat and cooling requirements, respectively, in Strategy A. The market competitiveness of Strategy A was evaluated by determining the minimum selling price through techno-economic analysis, and sustainability was thoroughly investigated by quantifying the environmental impacts through both midpoint and endpoint life-cycle assessments（LCAs）.Strategy A was found to be the most favorable both economically（USRDSCHARDOLLAR3,402/ton） and environmentally（-26.9 kg CO2eq.）. This indicates that lignin valorization is not only economically but also environmentally preferred. Finally, changes in economic and environmental feasibilities depending on economic, process, and environmental parameters were investigated using sensitivity and uncertainty analyses. The results of these analyses provide valuable insight into bio-based chemical production.

关键词： Biorefinery Carbon mitigation Climate change Global warming Lignin utilization Bioeconomy

Photoluminescence enhancement of red-emitting GdVO_4:Eu and YVO_4:Eu phosphors by adding zinc

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journal of Rare Earths 2013年第1期31卷 13-17页

作者： k.Park j.kim k.Y.kim j.Y.kim Y.kim S.j.Dhoble Faculty of Nanotechnology and Advanced Materials Engineering Sejong University Department of Advanced Materials Engineering Hoseo University Department of Chemistry and Institute of Basic Sciences Dankook University Department of Physics R.T.M. Nagpur University

We synthesized the rare-earth activated Ro.94_xEuo.06ZnxVO4 （R： Gd and Y; 0〈_x〈_0.08） phosphors with a spherical mor- phology and a smooth surface by the ultrasonic spray pyrolysis. The annealed Ro.94_xEuo.06ZnxVO4 crystallized in the tetragonal zircon type structure, belonging to the space group of I41/amd. The incorporation of a small amount of Zn to Ro.94Euo.06VO4 improved the emission characteristics. The emission intensities of the Gdo.88EUo.06Zno.06VO4 and Yo.9Euo.06Zno.04VO4 phosphors at 619 nm were 72% and 2 1% stronger than those of the Gdo,94Euo.06VO4 and Yo.94Euo.06VO4 phosphors, respectively. We demonstrated that the addi- tion of Zn to Ro.94Euo.06VO4 was quite effective for improving the photoluminescent properties.

关键词： rare earths photolurninescence vanadate ultrasonic spray pyrolysis

Effect of Solute Contents of Al-Ni-Sr Alloy on Glass Forming Ability and Thermal Stability

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journal of Rare Earths 2004年第z2期22卷 73-77页

作者： Taek Soo kim j.k Lee H j.kim j C Bae Advanced Materials R&D Center Korea Institute of Industrial Technology994-32 Dongchun-dongYeonsu-kuIncheon 406-130Korea Advanced Materials R&D CenterKorea Institute of Industrial Technology994-32 Dongchun-dongYeonsu-kuIncheon 406-130Korea Advanced Materials R&D CenterKorea Institute of Industrial Technology994-32 Dongchun-dongYeonsu-kuIncheon 406-130Korea Advanced Materials R&D CenterKorea Institute of Industrial Technology994-32 Dongchun-dongYeonsu-kuIncheon 406-130Korea

Glass forming ability (GFA) and structural characterization of a new amorphous Al-Ni-Sr alloy melt spun were investigated on the theory of the factors for the glass formation. The GFA was varied with the ratio of Ni to Sr in detail and successful amorphous phase dispersed with 2 ～ 5 nm precipitates was prepared from Al-Ni5-Sr3. Thermal stability and crystallization behavior of the amorphous phase were determined by continuous and isothermal heating technique on DCS, resulting that the crystallization occurs by the growth of fcc Al nanocrystals on the preexistent nuclei.

关键词： glass formation crystallization Al base amorphous alloys rapid solidification

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

Synthesis and Magnetic Properties of Nanoparticles of Fe-Co Alloys and Their Oxides Prepared by Chemical Vapor Condensation

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journal of Materials Science & Technology 2004年第4期20卷 459-462页

作者： ZhenhuaWANG ZhidongZHANG C.j.Choi B.k.kim j.C.kim ShenyangNationalLaboratoryforMaterialsScienceandInternationalCentreforMateri~alsPhysics InstituteofMetalResearchChineseAcademyofSciencesShenyang110016China koreaInstituteofMachineryandMaterials 66Sangnam-DongChangwonKyungnam641-010Korea

Nanoparticles of Fe-Co alloys and their oxides with the particle size below 20 nm were prepared by chemical vapor condensation process. The pure Ar, Ar+1%O2, Ar+3%O2 and Ar+6%O2 were used as carrier gases, with iron carbonyl and cobalt carbonyl as the precursors. XRD patterns showed that Fe-Co metallic nanoparticles were synthesized by using pure Ar as carrier gas, and only metal oxides were obtained using Ar+(>3)%O2 as carrier gas. The HRTEM images and TG-DTA curves were used to study the core-shell structure of the different nanoparticles. The nanoparticles obtained in pure Ar consist of black core and light shell with thickness of 2~4 nm. However, in the particles obtained in Ar+6%02, the oxides core with visible lattice fringes are surrounded by thin shell.

关键词： Fe-Co Nanoparticles HRTEM CVC

THE EFFECT OF W ON THE REPASSIVATION BEHAVIOR OF Ni-ADDED STAINLESS STEELS

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Acta Metallurgica Sinica(English Letters) 2005年第4期18卷 489-496页

作者： j.X. Pan k. Y. kim jiuquan Iron ＆ Steel （Group） Co. Ltd Jiayuguan 735100 China Pohang University of Science and Technology Pohang 790-784 Korea

The effect of W on the repassivation behavior of Ni-added stainless steels was investigated with respect to the repassivation rate and the SCC susceptibility. It was found that more stable passive film was formed on the W-modified stainless steels than that of steels without W-modification, and the repassivation rate was faster for W-modified stainless steels in acidic chloride solution （0.5M H2SO4＋3.5% Cl^-）. In neutral chloride solution （1M MgCl2）, there were no significant differences on both passivation properties and the repassivation rates for duplex stainless steels, while W-modified austenite stainless steel showed faster repassivation rate. The SCC tests verified that W-modified Ni-added stainless steels exhibited better SCC resistance than steels without W in chloride solution. Moreover, W-modification in higher Ni-added stainless steels exhibited more remarkable SCC resistance than steels with lower Ni content in chloride solution.

关键词： stainless steel repassivation stress corrosion cracking scratching electrode technique

Power management unit chip design for automobile active-matrix organic light-emitting diode display module

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journal of Central South University 2009年第4期16卷 621-628页

作者： kim j H PARk j H kim j H CAO T V LEE T Y BAN H j YANG k kim H G HA P B kim Y H Department of Electronic Engineering Changwon National University 9 Sarim-Dong Changwon 641-773 Korea Denso PS Electronics Corporation 47 Seongsan-Dong Changwon 641-315 Korea

A power management unit （PMU） chip supplying dual panel supply voltage, which has a low electro-magnetic interference （EMI） characteristic and is favorable for miniaturization, is designed. A two-phase charge pump circuit using external pumping capacitor increases its pumping current and works out the charge-loss problem by using bulk-potential biasing circuit. A low-power start-up circuit is also proposed to reduce the power consumption of the band-gap reference voltage generator. And the ring oscillator used in the ELVSS power circuit is designed with logic devices by supplying the logic power supply to reduce the layout area. The PMU chip is designed with MagnaChip＇s 0.25 μ high-voltage process. The driving currents of ELVDD and ELVSS are more than 50 mA when a SPICE simulation is done.

关键词： DC-DC converter AMOLED charge pumping power management unit (PMU) dual panel supply voltage

MOLECULAR DESIGN OF LIGHT EMITTING POLYMERS

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Chinese journal of Polymer Science 2000年第3期18卷 227-237页

作者： j.W.Yu j.k.kim j.MHong Y.C.kim H.N.Cho D.Y.kim C.Y.kim Polymer Materials Laboratory Korea Institute of Science and TechnologyP.O.Box 131CheongryangSeoul 130-650.Korea

Fluorene-based alternating and statistical copolymers were synthesized by employing reaction methods of Wittig,Heck and *** copolymers were classified into three groups with the photoluminescence(PL)emission maxima at420,475 and 500 nm,*** copolymers with two chromophores having PL emission maxima at 420 and475 nm emitted light with the emission maximum at 475 nm on photoexcitation at 365 nm and improved the quantumefficiency by the energy ***,the intramolecular energy transfer was inefficient compared to the intermolecularenergy transfer when the two chromophores were apart from each other in the range of the Forster critical ***-pyridinedivinylene alternating copolymer was synthesized by the Wittig reaction and found to have physical,electronic andelectrochemical properties of the individual units *** double-layered light emitting diode(LED)with the statisticalcopolymer as an emitting layer and the pyridine-containing copolymer as an electron transporting-hole blocking layer,whichwere sandwiched between ITO and Al,displayed a quantum efficiency of 0.1%.

关键词： Light emitting polymers

Numerical Simulation of Duct Flow with Fog Droplets

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journal of Thermal Science 2010年第6期19卷 533-539页

作者： Abhilash Suryan j. k. Lee D. S. kim H. D. kim Department of Mechanical Engineering Andong National University FMTRC Daejoo Machinery Co.

Evaporative cooling is a widely used air cooling technique. In this method, evaporation of a liquid in the surrounding air cools the air in contact with it. In the current investigation, numerical simulations are carded out to visualize the evaporation and dynamics of tiny water droplets of different diameters in a long air duct. The effect of initial droplet size on the temperature and relative humidity distribution of the air stream in the duct is investigated. Three different initial conditions of air are considered to verify the influence of ambient conditions. Droplet spray patterns are also analyzed to identify the suitable locations for the spray nozzles within the duct. The resuits obtained are displayed in a series of plots to provide a clear understanding of the evaporative cooling process as well as the droplet dynamics within the ducts.

关键词： Evaporative cooling Fog droplet Two-phase flow Relative humidity