• 대한화학회지
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• 제68권1호
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• pp.9-11
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• 2024

• Applied Biological Chemistry
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• 제35권4호
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• pp.248-253
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• 1992

재래식 메주와 개량식 메주로 각각 담아 숙성시킨 된장의 향기성분을 연속 수증기증류 추출장치로 추출하여 상압에서 농축한 후, preparative GC로 GC-관능검사를 하고 GC/MC 분석과 Kovats retention index를 비교하여 동정하였다. 재래식 메주로 담은 된장의 향기성분으로는 alcohol류 11종, aldehyde류 4종, pyrazine류 2종, acid류 4종, furan류 3종, phenol류 3종, ester류 3종, hydrocarbon류 3종, ketone류 1종, 기타 성분 5종 등 39가지의 성분을 동정하였다. 개량식 메주로 담은 된장의 향기성분으로는 alcohol류 4종, aldehyde류 2종, pyrazine류 2종, acid류 2종, furan류 1종, ester류 2종, hydrocarbon류 1종, ketone류 2종, 함황 화합물 1종, 기타 성분 4종 등 21가지의 성분을 동정하였다. 한편, 재래식 메주로 담은 된장과 개량식 메주로 담은 된장에서 함께 동정된 향기성분으로는 3-methyl-1-butanol, 4-methyl-3-heptanol, trimethyl-pyrazine, 1-octen-3-ol, 2-furancarboxaldehyde, tetramethyl-pyrazine, benzaldehyde, 3-methyl-butanoic acid, naphthalene, 2-ethyl-3-methyl-oxetane 등 10가지 성분이었다.

• 한국산업보건학회지
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• 제11권3호
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• pp.212-218
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• 2001

This study was performed to estimate environmental and biological monitoring of workers exposed to methyl bromide through quarantine fumigation. Airborne methyl bromide and it's metabolites were analyzed by gas chromatography and ion chromatography, respectively. The results are as followings; airborne concentration of methyl bromide(TWA) was $2.08{\pm}1.56ppm$(N=8). Dispersion and setting/degas groups were $0.67{\pm}0.12ppm$(N=2) and $2.54{\pm}1.53ppm$(N=6), respectively. Bromide ion concentration in serum was $23.40{\pm}14.91mg/{\ell}$(N=10) in the exposed workers and $4.74{\pm}0.82mg/{\ell}$(N=21) in the non-exposed workers. Bromide ion concentration in urine was $35.56{\pm}26.89mg/{\ell}$(N=11) in exposed group and $6.62{\pm}2.31mg/{\ell}$(N=21) in non-exposed group. Good correlation was observed between concentration of serum and urine ($r^2$=0.890 p<0.01). No significant correlations of other determinants were observed. Calculated from a regressive curve, the biological half lifes of serum and urine were 10.7 and 5.9 days. In these results, biological monitoring of bromide ion of serum and urine provided useful information for evaluating exposure of workers to methyl bromide, so that an availability of bromide ion of biological samples was showed as biological monitoring indices for methyl bromide.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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• pp.214-214
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• 2011

The adsorption and reactions of methanol and methyl iodide on ZnO(0001) and ZnO(11-20) single crystal surfaces have been investigated using the temperature programmed desorption (TPD) technique. The interaction of methanol and methyl iodide with ZnO is stronger on the polar ZnO(0001) surface than the non-polar ZnO(11-20) surface. On ZnO(0001), methanol is decomposed to produce formaldehyde and hydrogen. Two desorption features of formaldehyde and hydrogen are observed at around 500 and 580 K. The interaction of methanol and pre-adsorbed hydrogen has been also investigated. The reaction mechanism of methanol on ZnO will be proposed.

• Macromolecular Research
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• 제11권6호
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• pp.514-517
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• 2003

In the solution polymerizations of methyl methacrylate with (${\alpha}$-diimine)nickel(II)/methylaluminoxane (MAO), we observed effects of the position of two methyl substituents in the ligand on both the activities of the catalysts and the polymer microstructure. ${\alpha}$-Diimine nickel(II) catalysts gave syndiotactic-rich poly(methyl methacrylate) with high molecular weight and narrow molecular weight distribution.

• 한국식품영양학회지
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• 제12권5호
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• pp.513-517
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• 1999

Theessential oils of anise darkopal lettuce and sweet basils cultivated in Korea were extracted by simulatneous steam distillation and extraction method and were analyzed by GC/MSD. Total 41 com-ponents were identified in essential oils including 11 alcohols, 6 carbonyls 19 hydrocarbons and 5 esters components. The major components were 1,8-cineole linalool $\alpha$-bergamotene $\beta$-elemene methyl chavicol, $\beta$-cubebene methyl cinnamate and eugenol. Darkopal lettuce and sweet basils were rich in linalool(30.1-36.5%) methyl chavicol(8.1-25.5%) and relatively poor in methyl cinnamate(0-2.71%) Anise basil was rich in linalool(28.5%) and methyl cinnamate(23.1%) However methyl chavicol which was known as one of the main components of bisil was not detected.

• Biomolecules & Therapeutics
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• 제15권1호
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• pp.46-51
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• 2007

Bioassay-directed chromatographic fractionation of an ethyl acetate extract from leaves of sweet potato (Ipomoea batatas L.) afforded six quinic acid derivatives: 3,5-epi-dicaffeoylquinic acid (1), 3,5-dicaffeoylquinic acid (2), methyl 3,5-O-dicaffeoylquinate (3), methyl 3,4-dicaffeoylquinate (4), methyl 4,5-dicaffeoylquinic acid (5),4,5-dicaffeoylquinate (6), and two phenolic compounds: caffeic acid (7) and caffeic acid methyl ester (8) together with three flavonoids: quercetin 3-O-${\beta}$-D-glucopyranoside (9), quercetin 3-O-${\beta}$-D-glucopyranoside, isoquercitrin (10) and kaempferol 3-O-${\beta}$-D-glucopyranoside (11). The structures of these compounds were elucidated by the aid of spectroscopic methods. These compounds were assessed for antioxidant activities using three different cell-free bioassay systems. All isolates except 11 showed potent DPPH and superoxide anion radicals scavenging, and lipid peroxidation inhibitory activities. 3,5-epi-DCQA (1) and methyl quinates (3-5) along with flavonoide 9 were isolated for the first time from this plant.

• 한국식품과학회지
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• 제29권6호
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• pp.1144-1150
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• 1997

찹쌀로 담금한 콩고오지 사용의 개량식 고추장 숙성과정 중 휘발성 향기성분을 purge and trap 장치로 포집하여 GC-MSD로 분석 , 동정한 결과 alcohol 16종, ester 15종, acid 7종, aldehyde 4종, alkane 5종, ketone 3종, benzene 1종, alkene 1종, phenol 2졸, 기타 2종 등 56종의 휘발성 향기성분이 동정되었다. 동정된 향기성분 수는 담금직후에 alcohol 9종, ester 8종, aldehyde 3종 등 총 32종이 검출되었으나, 30일에는 alcohol 5종, ester 6종을 비롯한 15종이 추가 검출되어 46종으로 증가되었다. 90일에는 55종으로 향기성분 수가 최대에 달하였다. 숙성 전 과정을 통하여 검출된 향기성분은 2-methyl-1-propanol, ethanol, 3-methyl-1-butanol 등 alcohol류 9종, methyl acetate, ethyl acetate, 2-methylpropyl acetate 등 ester류 8종, butanal, acetaldehyde, furfural 등 aldehyde 3종, 기타 11종 등 총 31종이었다. 향기성분의 면적비율(peak area%)은 숙성기간에 따라 다소 차이가 있으나 ethanol. ethyl acetate, ethyl butanoate, 2-methylpropyl acetate, 2-methyl-1-propanol, 3-methyl-1 -butanol 등이 높아 이들 성분이 콩고오지사용 고추장의 향미 주 성분으로 나타났다 이들성분 중 숙성시기별로 가장 높은 면적비율을 보인 향기성분은 담금직후와 90일에 ethanol, $30{\sim}60$일에는 ethyl acetate 가, $120{\sim}150$일에는 3-methyl-butanol 이었다.

• 한국응용과학기술학회지
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• 제15권2호
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• pp.93-99
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• 1998

2-phenyl-N-methyl-1,3-thiazolium perchlorate(PTP)derivatives were synthesized via addition and substitution reactions. PTP was hydrolyzed under aqueous hydrochloride. The structures of the compounds were conformed by N.M.R.,I.R., and elemental analysis.

• Archives of Pharmacal Research
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• 제11권1호
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• pp.52-55
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• 1988

From the ether soluble alkaloidal fraction of Panax ginseng, 4-methyl-5-thiazoleethanol, norharman and barman were isolated. 4-Methyl-5-thiazoleethanol was isolated for the first time from natural resources.