• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.10
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• pp.768-772
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• 1998

The new type polymer electrolyte composed of polymethyl methacrylate(PMMA) - polyethy leneoxide(PEO) contain $LiClO_4$ -EC/PC was developed for the weightless and long or life time of lithium polymer batery system with using polyaniline electrode. the gel type electrolytes were prepared by PMMA with PEO at different lithium salts in the glove box. The minimum thickness of PMMA-PEO gel electrolyte for the slim type is about(400~450$\mu\textrm{m}$. These gel electrolyte showed good compatibility with lithium electrode. The test cell Li/polymer electrolyte/polyaniline solid state cell which was prepared by different lithium salt was researched by electrochemical technique.

• Proceedings of the KIEE Conference
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• 2005.07c
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• pp.1838-1840
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• 2005

Dielectric and conductive spect frequency spectra in a $1Hz{\sim}13MHz$ range have been measured for the composite consisting of PZT inclusions dispersed in a $LiClO_4$ doped polyethylene oxide(Li_PEO) matrix with various volume fractions. The dielectric and conductive spectra of the composites revealed the relaxations related with electrode polarization and interfacial polarization The observed spectra were reproduced using the empirical function and we could obtain vairous parameters related to electrode polarization and interfacial polarization.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.20 no.4
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• pp.383-398
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• 2022

The electrochemical behavior was investigated during the electrolysis of nickel oxide in LiCl-Li₂O salt mixture at 650℃ by changing several components. The focus of this work is to improve anode design and shroud design to increase current densities. The tested components were ceramic anode shroud porosity, porosity size, anode geometry, anode material, and metallic porous anode shroud. The goal of these experiments was to optimize and improve the reduction process. The highest contributors to higher current densities were anode shroud porosity and anode geometry.

• Polymer(Korea)
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• v.25 no.4
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• pp.602-607
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• 2001

Bis(2-methoxyethyl)itaconate (bis(ME)I) was prepared for a new gel electrolyte containing double comb-like itaconate unit by esterification reaction of 2-methoxyethanol with itaconic acid. The copolymers were composed of AN/bis(ME)I = 9/1 ~ 1/1. The optimum mechanical properties and conductivity were obtained from the composition of AN/bis(ME)I = 5/1 and 6/1(25 ~ 35 wt%), LiClO4$_4$(15 wt%) and plasticizer (EC/PC = 1/1) (40 ~ 50 wt%). They showed a tough film and maintained a mechanical stability as a free standing film. The plasticized polymer gel electrolytes obtained from them showed ion conductivity of 8.12 ${\times}$ 10$_{-4}$ ~ 1.87 ${\times}$ 10$_{-3}$ S/cm. The maximum conductivity value obtained from our study was one order of magnitude higher than that of other PEO-based polymer electrolyte at ambient temperature.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.30 no.3
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• pp.1-6
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• 1998

Elementally Chlorine Free (ECF) bleaching will be superior than Totally Chlorine free (TCF) bleaching, not only because they have no significant difference in effluent toxicity, but also those pulps bleached by ECF have higher brightness, strength, yield, etc., over those by TCF. With this belief, this paper focused on the chemistry of chlorine dioxide decomposition and ionization, both in water solution and in pulp slurry. Special attention was paid to chlorate ion because there have been controversies as how it is formed and what its behavior to the end pH of pulp bleaching is. As a result, during ionization of chlorine dioxide with water, both chlorate and chlorite were found to increase with increasing pH, but during ionization with pulp, chlorite was found to increase with end pH while chlorate decreased with increasing end pH. In the case of ionization with water, the disproportion equation $2CIO_2 + OH^{-} \lightarrow H_2O + CIO_3^{-} + CIO_2^{-}$ was thought to become the main reaction with the increasing pH, while in the case of ionization with pulp, the reaction $HCIO + CIO_2^{-}\lightarow H^{+} + Cl^{-} + CIO_3^{-}$ was the main reaction contributing to the formation of chlorate. Based on this above opinion, the contrary results of chlorine dioxide ionization from different researchers were discussed and explained.

• Proceedings of the KIEE Conference
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• 2005.07c
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• pp.2022-2024
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• 2005

Electrical double-layer capacitor (EDLC) is an electrochemical energy storage device in which electric charges only accumulated by a pure electrostatic attraction force are stored on the electrolyte-electrode interface in a form of double layer and separated by the electrolyte. The composite was prepared by mixing nanosize $TiO_2$ and activated carbon through a means of ultrasonic vibration in ethanol solution for 30 min in various mass ratios of $AC:TiO_2$ to form activated carbone-semiconducting oxide composites. Either 1.0 M $LiClO_4/EC-DEC$ or $Et_4NBF_4$/EC-DEC was used as the electrolyte. It was found that with modification of $TiO_2$, the specific capacitance of activated carbon measured at $1mA/cm^2$ was increased from 40 to 50 F/g. This method is unique in comparison the conventional method because it uses semiconducting TiO2 other than electrochemically active materials such as $RuO_2$. The increase in specific capacitance could be attributed to the decrease in electric polarization, caused by the introduction of $RuO_2$.

• Journal of the Korean Electrochemical Society
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• v.22 no.4
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• pp.164-171
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• 2019

Nano-sized $SnO_2$ powders were synthesized via a solvent thermal reaction using $SnClO_4$, NaOH, and ethylene glycol at $150^{\circ}C$. TGA, SEM, FT-IR, XRD, and Potentiostat/Galvanostat were employed to investigate the chemical and electrochemical characteristics of the synthesized $SnO_2$. The structure of $SnO_2$ was amorphous, and when heat treated at $500^{\circ}C$, it was transformed into a crystalline structure. The morphology obtained by SEM micrographs of the as-synthesized $SnO_2$ showed powder features that had diameters ranging 100 to 200 nm. The electrochemical performance of the crystalline $SnO_2$ as a Li-air battery cathode was better than that of the amorphous $SnO_2$. The specific capacity of the crystalline $SnO_2$ was at least 350 mAh/g at 10 mA/g discharge rate. However, there was some capacity loss of all the cells during the consecutive cycles. Keywords : Lithium-Air Battery.

• Carbon letters
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• v.25
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• pp.84-88
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• 2018

At present, an important research area is the search for materials that are compatible with CMOS technology and achieve a satisfactory response rate and modulation efficiency. A strong local field of graphene surface plasmon polariton (SPP) can increase the interaction between light and graphene, reduce device size, and facilitate the integration of materials with CMOS. In this study, we design a new modulator of SPP-based cycle branch graphene waveguide. The structure comprises a primary waveguide of graphene-$LiNbO_3$-graphene, and a secondary cycle branch waveguide is etched on the surface of $LiNbO_3$. Part of the incident light in the primary waveguide enters the secondary waveguide, thus leading to a phase difference with the primary waveguide as reflected at the end of the branch and interaction coupling to enhance output light intensity. Through feature analysis, we discover that the area of the secondary waveguide shows significant localized fields and SPPs. Moreover, the cycle branch graphene waveguide can realize gain compensation, reduce transmission loss, and increase transmission distance. Numerical simulations show that the minimum effective mode field area is about $0.0130{\lambda}^2$, the gain coefficient is about $700cm^{-1}$, and the quality factor can reach 150. The structure can realize the mode field limits of deep subwavelength and achieve a good comprehensive performance.

• Journal of Biomedical Engineering Research
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• v.8 no.2
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• pp.123-134
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• 1987

The transport phenomena of alkali metal chlorides through poly(2 hydroxyethyl methacrylate) hydrogel membrane have been studied using electrodialysis. The hydrogel membranes were prepared by the polymerization of 2-hydroxvethyl methacrylate in the presence of 45%(V/V) H2O and ethyleneglycodimethacrylate. The initiator used in the polymerization was azobismethylisobutyrate (AMIB) prepared from azobisiobtyronitrile (AIBN) using Mortimer method. The permeability of alkali metal chlorides such LiCl, NaCl and KCI at 50 voltage was obtained. The permeability of NaCl was also observed at 30, 40, 50, and 60 voltages respectively. The concentration of solutes permeated through the membrane was measurer by flame photometry. The experimental results have been discussed with the comparison of apparent solute molecular size, the self-diffusion coefficient of solutes, the transport number of cations in aqueous solution. These indic aloes that poly(2 hydroxyethyl methacrylate) hydrogel membrane shows a specific selectivity for sodium ion.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.172.1-172.1
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• 2011

본 연구에서는 매립지에서 발생하는 주요한 가스인 $CO_2$(47~55%)와 $CH_4$(47~55%)가스를 분리하기 위하여 여러 $CO_2$ capture 방법 중 Zeolite를 사용한 흡착법을 이용하였다. 국내에서 시판되고 있는 powder형 Zeolite 13X에 Inorganic binder와 organic binder를 최적의 비율로 혼합한 후 증류수를 이용하여 Pellet type 흡착제를 제조하였다. 또한 최종적으로 $CO_2$의 흡착능을 높이기 위하여 양이온(1M의 KCl, NaCl, $CaCl_2$, $LiCl_2$)으로 이온교환을 하였다. 매립지 모사가스($CO_2$:40%, $CH_4$:60%)를 이용하여 실시간 분석기(Delta1600S)를 이용 두 가스의 분리와 $CO_2$ 흡착성능(mg-CO2/g-흡착제)을 확인하였다. 개발된 흡착제(AjouEpl 13X)는 ICP, XRD, XRF, BET 분석으로 제올라이트의 구조와 성분을 분석하였다.