• 공업화학
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• 제9권4호
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• pp.603-607
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• 1998

Cellulose를 출발물질로 하여 ethylene oxide와 hydroxyethylcellulose를 합성하였다. Epichlorohydrin과 triakylamine을 치환반응시켜 제4급 암모늄염을 만든후, 산을 첨가하여 3-chloro-2-hydroxypropyltrialkylammonium chloride를 얻었다. Hydroxyethylcellulose와 glycidylalkylammonium chloride 또는 3-chloro-2-hydroxypropyltrialkylammonium chloride를 coupling하여 지금까지 알려져 있지 않은 화합물 hydroxyethylcellulose-2-hydroxypropylammonium chloride ether와 hydroxyethyl-cellulose-2-hydroxypropyltriethylammonium chloride ether를 각각 73.9%, 74.2%의 수율로 합성하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1996년도 추계학술대회 논문집
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• pp.109-112
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• 1996

The purpose of this study is to research and develop solid polymer electrolyte(SPE) for all-stolid-state lithium battery. We investigated conductivity, electrochemical properites and impedence spectroscopy of poly(ethylene oxide)[PEO]/poly(vinylidene fluoride)[PVOF] blend electrolytes and charge/discharge cycling of LiCoO$_2$/SPE/Li cell. By adding PVDF and plasticizer to PEO-LICIO$_4$electrolyte, its condustivity was higher than that of PEO-LiCIO$_4$electrolyte. Also PEO$_4$PVDF$_4$LiClO$_4$PC$_{5}$EC$_{5}$ remains stable up to 4.4V vs Li/Li. The discharge capacity of the LiCoO$_2$composite cathode was 92mAh/g based on LiCoO$_2$.EX>.

• 복식문화연구
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• 제12권4호
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• pp.591-598
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• 2004

This study examines the effects and influences of fumigation using chemical composite of Methyl Bromide and Ethylene Oxide on the change of strength of excavated dresses. The fabric strength immediately after washing and fumigation increased slightly, but it decreased greatly as the time progressed. The strength of the test sample from Museum A showed a steady decrease with time, while that of Museum B decreased rapidly 5 months later. Compared with the non-fumigated sample, fumigated sample was greater in strength regardless of the time progression, and the strength of sample kept in the exhibit hall was greater than that kept in the storage room. The strength of the fumigated sample was almost same regardless of the three different time periods, before washing, after washing and immediately after fumigation, and it decreased steadily with time, whereas the non-fumigated sample became much weaker in its strength in 10 months after washing. Even 5 months later, the fumigated sample was about as strong as immediately after fumigation, but the strength dropped to a great extent 10 months later.

• 한국환경과학회지
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• 제1권1호
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• pp.69-76
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• 1992

The effects of $Ca_{2+}$ ion on the formation of micelle colloid of nonionic surfactants, nonylphenol-(ethylene oxide)n [NP-(EO)n: n= 11, 40, 100) were investigated by the iodine solubilization method. The characteristics of spectra depended on the concentration of $Ca_{2+}$ ion and the number of EO unit. Above CMC(critical micelle concentration), the intensity of the CT (charge transfer) band by the addition of $Ca_{2+}$ ion for the NP-(EO)11 and NP-(EO)40 increased and when decreased and for the NP-(EO)In continuously increased. The increase in the intensity of CT band were attributed to the compactness of micelle in the presence of $Ca_{2+}$ ion. These phenomena may be explained by the fact that the linear ethylene oxide (EO) chain, relatively free to assume various configuration in aqueous solution, could form a pseudo-crown ether structures capable of forming complexes with $Ca_{2+}$ ion.

• Transactions on Electrical and Electronic Materials
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• 제13권3호
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• pp.136-138
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• 2012

The electrical characteristics of complex films composed of poly(ethylene oxide) (PEO) and urea as a function of the urea concentration were examined in this study. Moreover, their structural characteristics were also compared. Depending on the urea concentration, the structural phases were classified as PEO+${\beta}$-phase composite, ${\beta}$-phase+${\alpha}$-phase composites, or ${\alpha}$-phase composite+urea. At urea concentrations below ~0.064 M, the ${\beta}$-phase was dominant in the complex film. Moreover, the conductance increased rapidly with an increase in the urea concentration. For urea concentrations ranging from ~0.064 to ~0.25 M, the ${\beta}$-phase was gradually substituted by the ${\alpha}$-phase. As the film was composed entirely of the ${\alpha}$-phase at urea concentrations greater than ~0.25 M, its conductance was decreased. In this study, the electrical characteristics observed for the different phases are analyzed and discussed.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1996년도 추계학술대회
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• pp.327-330
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• 1996

Poly(L-leucine)(PLL)/poly(ethylene oxide)(PEO)/poly (L-leucine)(PLL) block copolymers were synthsized by polymerization of L-leucine N-carboxyanhydride with diamine-terminated PEO for possibility of wound dressing which may have several advantages such as 1) increase of solubility, 2) control of biodegradation, 3) absorption of body fluid. 4) non-immunogenic effect than PLL homopolymer wound dressing aleady commercialized. Water content increased with an increase of PEO content in the block copolymer due to the hydrophilicity of PEO. Release of silver sulfadiazine(AgSD) from AgSD loaded wound dressing increased with an increase of PEO content in the block copolymer. It was found that the number of Pseudomonas aeruginosa decrease with an increase of PEO content due to the fast release of antibacterial agents with an increase of PEO content in the block copolymer.

• Bulletin of the Korean Chemical Society
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• 제21권4호
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• pp.383-388
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• 2000

Multiblock copolymers consisting of poly( g-benzyl L-glutamate) (PBLG) as the hydrophobic part and poly(ethylene oxide) (PEO) as the hydrophilic part (GEG) were synthesized and characterized. GEG polymeric micelles were prepared by the dialysis technique. Particle size distributions based on intensity,volume, and number-average were 22.6 $\pm$ 11.9 nm, 23.5 $\pm$ 4.6 nm, and 23.7 $\pm$ 37 nm, respectively. It was observed that par-ticle size and size distribution of GEG polymeric micelles changed significantly with the choice of initial sol-vent. Transmission electron micrographs (TEM) showed the polymeric micelles to be spherically shaped, with sizes ranging from 20 nm to 40 nm in diameter. Fluorescence spectroscopy measurements suggested that GEG block copolymers wereassociated in water to form polymeric micelles, and the critical micelle concentrations (CMC) value of the block copolymers was 0.0094 g/L. Further evidenceof micelle formation of GEG block copolymers and limited mobility of the PBLG chain in the core ohe micelle was obtained with 1 H NMR in D2O.

• 한국식품저장유통학회지
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• 제1권1호
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• pp.21-27
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• 1994

For the purpose of improving microbiolgical quality of carrot powder, which is being used as minor ingredients of convenience foods, comparative influence of Υ-irradiation and ethylene oxide(E.O) fumigation was investigated with emphasis on sterilizating effect and physicochemical propertied Carrot powder sample was contaminated with thermophiles 4.0$\times$103/g, acid tolerant bacteria 3.7$\times$103/g and coliforms 1.6$\times$102/g, respectively. And thus sanitation process was required. E.O fumigation in commercial practice was not enough to destroy thermophilic bacteria, while Υ-irradiation at below 5 kGy could reduce all microorganisms up to undectected levels. Radiosensitivity(D10) of thermophiles was shown to be 2.25 kGy. The applicable dose of irradiation to the improvement of microbiological quality showed insignificant influences on the physicochemical quality of the sample.

• 한국식품저장유통학회지
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• 제2권1호
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• pp.163-171
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• 1995

Organoleptic qualities were evaluated putting emphasis on flavor and color of white ginseng powders which were treated with ethylene oxide(EO) and gamma radiation(5, 10kGy) for microbial decontaminations. Immediately after treatments, there was no significant changes in the overall flavor and color of the samples between the nontreated control and both treatments. The color of even airtight-packaged samples, however, was changed(p<0.05) after 7 months of storage at 30$\pm$2$^{\circ}C$ when treated with EO and 10 kGy. These changes in color were confirmed by the instrumental determinations for the stored samples. Thus, it can be proposed that gamma Irradiation below 10kGy combined with airtight packaging is required for keeping the organoleptic quality of white ginseng powders for more than 6 months of storage.

• Journal of Electrochemical Science and Technology
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• 제10권2호
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• pp.250-255
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• 2019

Poly(ethylene oxide) (PEO)-based solid polymer electrolytes (SPEs) show promise for improving the lithium ion battery safety. However, due to oxidation of the PEO group and corrosion of the Al current collector, PEO-based SPEs have not previously been effective for use in $LiCoO_2$ (LCO) cathode materials at room temperature. In this paper, a semi-interpenetrating polymer network (semi-IPN) PEO-based SPE was applied to examine the performance of a LCO/SPE/Li metal cell at different voltage ranges. The results indicate that the SPE can be applied to LCO-based lithium polymer batteries with high electrochemical performance. By using a carbon-coated aluminum current collector, the Al corrosion was mostly suppressed during cycling, resulting in improvement of the cell cycle stability.