• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.167-168
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• 2009

Phase pure barium magnesium tantalate $Ba(Mg_{1/3}Ta_{2/3})O_3$(BMT) nanopowders were synthesized at temperature as low as $220^{\circ}C$ through glycothermal reaction by using $Ba(OH)_2{\cdot}8H_2O$, $Mg(NO_3){\cdot}6H_2O$, and $TaCl_5$ as precursors and 1,4-butandiol as solvent. XRD, SEM, and TGA data support that glycothermal processing method provides a simple low temperature route for producing fine grained BMT nanopowders without alkaline mineralizers. BMT nanopowders synthesized at $220^{\circ}C$ showed more homogenous with rounded morphologies.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2005.11a
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• pp.417-421
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• 2005

Novel two synthetic technics using cationic ring-opening copolymerization of tetrahydrofuran (THF) and ethylene oxide (EO), or just polymerized EO on Poly-THF, could lead to random hydroxyl-terminated poly(EO-ran-THF) or tri-block PEG-PTHF-PEC, respectively. These reactions were carried out using $BF_3O(C_2H_5)_2$ as catalyst, 1,4-butanediol or PTHF as diol initiator. Copolymer structures were controlled by monomer feed ratio, or initial PTHF and EO monomer added amount. The molecular weight of polymer was merely dependant on the ratio of [monomer]/[diol], but not on catalyst. Well-defined random and block hydroxyl-terminated copolyether was found to be as the prepolymer for the propellant binder from the experiment to polyurethane with them.

• Polymer(Korea)
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• v.35 no.2
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• pp.146-151
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• 2011

The physical properties of poly (ethylene 2,6-naphthalate) (PEN) copolymers were studied. PEN copolymers were synthesized successfully from the mixtures of ethylene glycol(EG), 1,3-propanediol (PD) and l,4-butanediol (BD) with 2,6-dimethyl naphthalene dicarboxylate. The results indicated that PEN copolymers showed an amorphous state when the content of BD(PD) in applied EG/BD(EG/PD) mixtures was less than 40% during the polycondensation. As a result, the lowering of thermal properties, orientation, and mechanical properties was found, however, the dimensional stability was improved. This is a promising result to apply the synthesized PEN copolymers as flexibles substrates.

• Bulletin of the Korean Chemical Society
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• v.19 no.9
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• pp.957-961
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• 1998

Intramolecular Diels-Alder cycloadditions of 2-pyrone-3-carboxylates with trans-vinyl silaketal groups tethered via a chiral, non-racemic 1,3-butanediol auxiliary proceeded in unexpected stepwise cycloadditions through ionic intermediates to provide cis-disubstituted bicylolactones. The ratio of two isomers, exo and endo, was 5 to 1, and each isomer was found to be diastereomerically pure (>99% de). Their relative and absolute stereochemistries were determined by $^1H$ NMR spectroscopy and confirmed by X-ray crystallography of minor, endo-adduct 9. The major exo-adduct was successfully transformed to (-)-2-butyl substituted A-ring phophine oxide 16, a key element for the synthesis of 2-butyl vitamin D3.

• Korean Journal of Food Science and Technology
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• v.39 no.4
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• pp.360-365
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• 2007

The studies for the derivatization of 3-monochloropropane-1,2-diol (3-MCPD) were performed mainly as acylation with HFBI (heptafluorobutyrylimidazole), alkylation with PBA (phenylboric acid) and silylation with BSTFA (N,O-bis[trimethylsilyl]trifluoroacetamide). Also silylation with MTBSTFA(N-methyl-N-[tert.-butyldimethylsilyl] trifluoroacetamide) and acylation with MBTFA (N-Methyl-bis[trifluoro-acetamide]) were also considered. Except the TBDMS derivative of 3-MCPD, all the derivatives were detected well. The derivatives of 3-MCPD with HFBI, PBA and BSTFA showed below 10 ${\mu}g/kg$ which was sensitive enough to satisfy Korea maximum residue limit 0.3 mg/kg. Among the tested adsorbents, Extrelut20 and Florisil were evaluated as the proper adsorbents to eliminate the soy sauce matrix for 3-MCPD. Ethyl acetate was the most efficient eluent with good recovery rate. The desired surrogate compound and internal standard were 1,2-butanediol and 1,2-dibromo-3-chloropropane, respectively. The limit of detection for PB-MCPD and TMS-MCPD were 10.16 and 7.06 ${\mu}g/kg$ on GC/MSD, respectively. HFB-MCPD derivative showed the lowest detection limits 2.98 and 5.32 ${\mu}g/kg$ by GC/ECD and GC/MSD, respectively.

• Korean Journal of Food Science and Technology
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• v.37 no.6
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• pp.944-950
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• 2005

Volatile flavor components of Takjus mash prepared using Aspergillus kawachii nuruk were identified by GC and GC/MS. Twenty-two esters, 20 alcohols, 10 acids, 8 aldehydes, and 3 others were found in Takju mash. Thirty two components including 13 esters and 13 alcohols were detected at beginning of fermentation. Thirteen more components were detected after second day of fermentation, and 63 additional components after 12 days of fermentation. Twenty nine flavor components including 12 alcohols such as ethanol, 3-methyl-1-butanol, 2-methyl-1-propanol, and benzeneethanol, 12 esters such as ethyl acetate, ethyl caprylate, and ethyl butyrate 3 aldehydes, and 2 acids were detected during fermentation. Major volatile components detected during fermentation included 3-methyl-1-butanol, ethyl caprylate, and benzeneethanol. Peak areas of 2-methyl-1-propanol, 1-hexanol, 2, 3-butanediol (D.L), 1-dodecanol, 2-phenylethyl acetate, ethyl acetate, and monoethyl butanoate were higher than those of other components depending upon fermentation period.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.44 no.1
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• pp.1-7
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• 2018

In this study, 1,2-hexanediol, ethylhexylglycerin, and glyceryl caprylate known as skin conditioning agents with antimicrobial activity in cosmetics were investigated for their antimicrobial activity against gram-positive and gram-negative bacteria when combining them with various ingredients in cosmetic formulations. Seven kinds of substances expected to improve the antibacterial activity in formulations were selected to blend with these three compounds.; 1,3-propanediol, 1,3-butanediol, glycerin, dipropylene glycol, niacinamide, EDTA-2Na, and ethanol. The checkerboard assay was conducted to confirm the antibacterial synergy of these seven substances and the three skin conditioning agents. Consequently, ethanol and EDTA-2Na were detected as the significant materials with synergistic effect as well as ethanol showed antibacterial synergy with all the three compounds. When seven of selected materials were mixed with glyceryl caprylate, there were synergistic or additive activity against S. aureus, gram-positive bacteria and it was suggested that the combination with 1,2-hexanediol and glyceryl caprylate was useful to control both gram-positive and gram-negative bacteria when there were four kinds of polyols. This study is meaningful in that it confirmed the antibacterial synergy of the skin conditioning agents with antimicrobial activity and the main raw materials frequently used in cosmetics, thereby contributing to prediction of the antibacterial activity of the skin conditioning agents in cosmetic formulations.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.691-698
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• 2000

Volatile flavor components in the mash of takjus prepared by using Rhizopus japonicus nuruk were identified by using GC and GC-MS. Twenty-four esters, 19 alcohols, 9 acids, 10 aldehydes and 4 others were found in the mash of takju. Thirty nine components including 14 esters and 12 alcohols were detected in the beginning of fermentation. Seventeen components were more detected after second day of fermentation and 66 components were detected after 12 days of fermentation. Thirty eight flavor components including 12 alcohols such as ethanol, 2-methyl-1-propanol and 3-methyl-1-butanol, 14 esters such as ethylacetate, ethylcaprylate and isoamylacetate, 6 aldehydes and 5 acids were usually detected in the fermentation process. Ethanol was predominantly found in the range of 76.2149-92.1155% as a major component by using relative peak area. 3-Methyl-1-butanol, 2-methyl-1-propanol, ethyl caprylate, 2,3-butanediol and benzeneethanol were some of the major volatile components through the fermentation. Peak area of ethylacetate, diethyl succinate, octanoic acid, acetic acid and isobutylaldehyde among the same group were higher than other component depending upon fermentation time.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2005.10a
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• pp.234-239
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• 2005

본 연구는 재래흑돼지육의 진공포장 숙성중 지방산 조성과 SPME-GC/MS에 의한 향기성분을 구명하고자 실시하였다. 지방산 조성으로 C14:0, C16:1n7은 재래흑돼지육이 개량종 돼지육보다 낮았으며(p<0.05), C18:1n7, C22:4n6는 재래흑돼지육이 높았다(p<0.05). 숙성기간 동안 향기성분은 숙성 0일에 2-decanone, 2-ethyl hexanol, hexa -noic acid가 재래흑돼지육에서만 검출되었으며, 숙성 6, 12일에는 butanoic acid, 2.3-butanediol, benzen -acetaldehyde, benzeneethanol, 2-hexadecal, hexanoic acid가 재래흑돼지육에서만 검출되었다.

• KSBB Journal
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• v.9 no.3
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• pp.246-252
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• 1994

Enzyme-catalyzed polycondensatlon reaction of aliphatic polyesters with several repeating units was studied using the biocatalytic activities of lipases from different sources. Porcine pancreatic lipase (PPL) was found to be best in utilizing bls(2,2,2-trichloroethyl) glutarate and 1,4-butanediol as substrafes. The reaction was also catalyzed to some extent by the lipases from Humicola lanuginos and Psudomonas sp. In the series of short-chain diols(C2-C4), bis(2,2,2-trichloroethyl) glutarate was iransesterified fastest with 1,4-butanediol and for the long-chain diols (PEG-300-PEG-1000), the reaction was fastest with PEG-400. With PEGs, only monoesterification product was obtained. PPL functioned well in relatively hydrophilic organic solvents such as tetrahydrofuran(THF), ether and acetonitrile. The reaction rate was accelerated as the reaction temperature was raised from $20^{\circ}C$ to $60^{\circ}C$ while Mn values of the reaction products were not affected by the reaction temperature. End group analysis by NMR showed that Mn values of the polymer were in the range of 1500-4000 daltons.