• 한국자동차공학회논문집
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• 제8권2호
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• pp.1-8
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• 2000

Recently, Our planet is faced with very serious problems related to the air pollution due to the exhaust emissions of the diesel engine. So, lots of researchers have studied to reduce the exhaust emissions of diesel engine that influenced the environment strong. But most researchers have mainly studied and suggested the solution of reduction on the total exhaust emissions of diesel engine. In this study, the quantities of the low and high hydrocarbon among the exhaust emissions in diesel engine have been investigated by the quantitative analysis of the hydrocarbon C1~C6 using the gas chromatography. This study carried out by comparing the chromatograms with diesel fuel and mixed fuel which are blended the diesel and DMC(dimethyl carbonate)that includes the oxygen of about 53%. The results of this study show that the hydrocarbon C1~C6 among the exhaust emissions of the mixed fuel are exhausted lower than those of the diesel fuel at the all load.

• 약학회지
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• 제32권3호
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• pp.170-176
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• 1988

The resolution of five amino acids derivatives by gas chromatography on phenylthiohydantoin derivatives as chiral stastionary phase was investigated. (S)-5-isopropyl, isobutyl, (sec)-butyl and benzoyl derivatives of $N^3-phenyl-2-thiohydantoin$ were synthesized from L-valine, L-leucine, L-isoleucine and L-phenylalanine, respectively. The phases were employed at several column temperatures ($140^{\circ}C{\sim}210^{\circ}C$). The separation factors were compared with each stationary phase with varying R groups. The possible mechanism of chiral recognition was investigated by NMR technique.

• 한국식품과학회지
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• 제20권6호
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• pp.774-779
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• 1988

참쑥(Artemisia lavandulaefolia DC)의 정유를 gas chromatogaphy/mass spectrometry(GC/MS)로 정성분석하고, 저장조건을 달리하여 정유성분의 변화를 살펴본 결과, 다음과 같은 결론을 얻었다. 1. 186 이상의 화합물이 검출되었으며, 그 중 1,8-cineol, camphor, ${\beta}-thujone$, caryophyllene, borneol, coumarin, linalool, terpineol, sabinene, 7-methoxy coumarin ${\alpha}-copaene$, humulene과phytol이 중요성분이었다. Artemisia species에서는 지금까지 밝혀진 바 없는 3,6,6-trimethyl norpinanol, ${\beta}-farnesene$, 7-methoxy coumarin, ${\alpha}-curcumene$ 등이 검출되었다. 2. 참쑥의 저장에 따른 색과 변화를 조사한 결과, 온도에 의해 갈색화와 성분의 증감이 있었다. 즉, 냉암소에 보관된 시료는 변화가 거의 없었으나, 상온방치한 시료는 Air와 질소에 상관없이 모두 변화가 있었다. 1,8-cineol, limonene, 2,2,4-trimethyl 1,3-dioxolane-4-ethanol, terpinene-4-ol 등은 감소하였으며, ${\beta}-phellandrene$, benzyl benzoate, broneol, ${\alpha}-terpineol$, humulene 등은 증가하였다.

• 대한약리학회지
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• 제31권2호
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• pp.261-269
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• 1995

Background; To explore the efficacy of aspartate as NAD regenerating agent for ethanol and acetaldehyde oxidation, we performed crossover challenge in two groups of volunteers by coadministration of various doses of aspartate, asparagine and ethanol. Methods; 18 healthy male volunteers were randomly divided into two groups. 6 volunteers of the first group were administered 5 gm monosodium aspartate(MSA), 5 gm asparagine or placebo with 100 ml of $40^{\circ}$ whiskey by the 3 way-crossover design, while 12 volunteers of the other group were administered placebo, 1, 2 or 5 bottles of $Aspar^(circledR)$ containing 1 gm of MSA per bottle with 100 ml of $40^{\circ}$ whiskey by the 4 way-crossover design. Ethanol(and acetaldehyde) concentrations in venous blood drawn at 0, 0.25, 0.5, 1, 2, 4, 8th hour after ethanol ingestion were analysed by gas chromatogaphy. Subjective symptoms, liver function tests and psychomotor function tests were also performed during the study periods. Result; Plasma concentration and AUC of acetaldehyde in asparagine and MSA trials on ethanol ingestion were significantly lower than those of placebo trial in the 1st group. Plasma ethanol concentration of 5 bottle $Aspar^(circledR)$ trial was significantly lower than that of placebo trial in the 2nd group. Improvement of subjective symptoms or psychomotor performance by the treatment was not statistically significant. Conclusion; Aspartate and asparagine may be prospective candidates for acceleration of ethanol metabolism and prevention of ethanol toxicity.

• 한국식품과학회지
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• 제19권4호
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• pp.361-365
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• 1987

유자의 이용성 확대를 위하여 유자원료와 유자차의 이화학적 특성, 향기성분 및 유자씨의 지방산조성을 분석하였다. 유자의 평균충량은 196g으로 이중 과즙이 18.8%, 씨 16.3%, 껍질 46.6%이고 과육이 28.3%였다. 유자원료의 당도는 $8.8^{\circ}\;Bx$, 산도 2.1%로 당산비율은 4.2이었고 유자차는 당도 $45^{\circ}\;Bx$, 산도 0.9%였다. 유자에는 fructose, glucose, sucrose가 각각 1.17%, 1.01%, 0.93% 함유되어 있으며 유자차에는 4.46%, 5.53%, 3.27%였다. 유자씨의 성분은 조지방 34.2%, 조단백 15.5% 함유되어 있고, 지방산은 palmitic acid 21.6%, stearic 3.1%, oleic 35.2%, linoleic 37.6%, linolenic이 2.6%였다. 유자의 향기성분은 limonene이 72.4%로 가장 많았으며 탄화수소류 17종, 알코올류 4종, 알데하이드 1종, 기타 6종을 포함 28종을 확인하였다.

• 농약과학회지
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• 제9권3호
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• pp.237-242
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• 2005

SFSI (Solvent free solid injector)를 이용하여 추출과 정제과정이 필요없는 신속한 농약잔류분석법을 개발하고, 이 분석법의 실효성 여부를 확인하고자 내분비계장애추정농약으로 알려진 endosulfan, metribuzin, trifluralin, 그리고 vinclozolin의 작물 중 잔류양상을 분석하였다. SFSI에 주입된 시료는 동결건조 후 사용하였으며, SFSI에서 시료의 충분한 기화를 위한 pre-heating time을 조사한 결과 endosulfan과 trifluralin은 1 분, metribuzin은 10 분, vinclozolin은 5 분이었다. 또한 농약들의 최소검출량은 endosulfan, metribuzin, trifluralin 그리고 vinclozolin에서 각각 0.05, 0.1, 0.05, 0.05 ng이었다. 분석대상농약의 작물별 회수율은 배추 중 endosulfan은 74%, 상추 중 metribuzin은 $98{\sim}107%$, 시금치 중 trifluralin은 $86{\sim}95%$, 그리고 고추 중 vinclozolin은 $94{\sim}95%$이었다. 현장시료에 적용해 본 결과 상추에서 metribuzin이 0.6 ng/mg 수준으로 검출되었다.