• International Journal of Automotive Technology
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• v.7 no.4
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• pp.399-406
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• 2006

The smoke emission of diesel engines is being recognized as one of the major source of the air pollution problems. This study investigates the potential of esterified rice bran oil to reduce smoke emission as an alternative fuel for diesel engines. Because the esterified rice bran oil has approximately a 10.5% oxygen content, the combustion of the diesel engine improved and exhaust smoke decreased. Gas chromatography was used to analyze not only the total amount of hydrocarbon but also the amount of hydrocarbon components from $C_1$ to $C_6$ in the exhaust gas to determine an exact source responsible for the remarkable reduction in the smoke emission. The number of individual hydrocarbon($C_1{\sim}C_6$) as well as the total amount of hydrocarbon of esterified rice bran oil reduced significantly compared to that of hydrocarbon of diesel fuel.

• Korean Journal of Oriental Medicine
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• v.1 no.1
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• pp.441-459
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• 1995

To study stability of distilled herbal medicine, we chose changes in UV spectrum, pH, conductivity, and HPLC chromatogram. Aconiti Lateralis preparata Radix and Scutellariae Radix were selected and studied. There ws no consistancy in UV spectrums of preparatons and in duration. The changes in pH and conductivity were not correlated to those in UV spectrums. HPLC chromatograms were also compared each other depending on the preparations. One interesting peak of distilled Aconiti solution was appeared at 40 min retention time which was not identified yet. Ingeneral, UV spectrum, pH, conductivity measurements are pretty poor tool to study stability of herbal medicine although HPLC analysis should be studied further.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.6
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• pp.1123-1126
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• 2000

수증기 증류법으로부터 얻은 배초향(Agastache rugo-sa, Labiatae)의 정유는 부패균을 포함하는 수종의 미생물에 대하여 현저한 항균활성을 나타내었다. 배초향의 유효성분을 확인하기 위하여 정유성분을 GC-MS로 분석한 결과 GC chromatogram에서 얻은 각 피크의 reten-tion time 및 mass spectral data 의표준물질과의 비교에 의해서 isomenthone, methone, dihydrocarvone, anetho-le, vanillin, eugenol, methyleugenol, $\beta$-caryophyllene, $\beta$-caryophyllene oxide 등의 정유성분이 확인되었다. 이 연구에서 밝혀진 여러 성분들의 항균 활성은 잘 알려져 있으므로 이들이 유효성분으로 추측된다. 또한 Korean mint로 세계적으로 알려져 있는 배초향의 정유는 식품 방부제로서 적합할 것으로 생각된다.

• Analytical Science and Technology
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• v.9 no.3
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• pp.320-324
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• 1996

The dynamic range of mass selected detector, which is very popular recently because of the simplicity and cheap price, was determined by using priority pollutants. The applied priority pollutants were four pesticides, 4,4'-DDE and 4,4'-DDD, which show the sharp peaks, and ${\alpha}$-endosulfan and ${\beta}$-endosulfan, which show the broad peaks in SIM Chromatogram. The dynamic range of the 4,4'-DDE and the 4,4'-DDD was $0.1{\sim}3000{\mu}g/ml$. The broad peaks of the ${\alpha}$-endosulfan and ${\beta}$-endosulfan resulted in $0.25{\sim}3000{\mu}g/ml$ of dynamic range.

• Microbiology and Biotechnology Letters
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• v.24 no.4
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• pp.439-444
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• 1996

Microorganisms were collected to isolate the microbes producing Kochujang flavor from 3 kinds of traditional Kochujang. The strain B7 and Y20 which scored the highest sensory evaluation value among 400 microorganisms were finally selected. Also, they showed the most similar flavor pattern to the traditional Kochujang's by comparison of GC chromatogram after sniffing test. As the result of the result of the morphological and physiological experiments, the bacterial strain B7 could be identified Bacillus licheniformis and the yeast strain Y20 Saccaromyces dairensis. Especially, the bacterial strain B7 could grow in anaerobic condition and was able to hydrolysis the starch that was the major component in Kochujang.

• Biomedical Science Letters
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• v.8 no.2
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• pp.101-106
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• 2002

The purpose of this study was to test the capacity of automatic tablet crusher. The Automatic tablet crusher not only saved crushing time, but also removed floating fine powders that was occurred during crushing and caused allergy. The characteristics of powder produced by this crusher were as follows: First, to meet the condition as powder after pulverizing 5∼10 g tablet it took 6 to 12 seconds crushing time. But six seconds would do to get powder f3r oral administration. Second, when the quantity of medicine was measured by HPLC, powder from automatic crusher showed higher than that from pestle. HPLC chromatogram indicated that there was no change of medicine in the process of pulverization.

• Applied Biological Chemistry
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• v.24 no.2
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• pp.145-148
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• 1981

A study has been conducted to ascertain persistency of p-chlorophenoxy acetic acid (CPA), a plant growth substance, in soil. CPA was extracted from soil and then converted to a gIc (ECD) sensitive derivative, 2-chloroethyl p-chlorophenoxy acetate (CPA ester) with $BCI_3$ as catalyst. Total recovery of CPA including the chemical conversion was 49.4% and detection limit of CPA in soil, a minimum concentration of the compound which can be identified on chromatogram, was 0.03 ppm. Half life of CPA in clay loam under field conditions was 20 days and that of CPA under laboratory condition was 27.4 days respectively.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.4
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• pp.33-42
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• 2002

Recently, our world is faced with very serious and hard problems related to the air pollution due to the exhaust emissions of the diesel engine. In this paper, the effect of oxygen component in fuel on the exhaust emissions has been investigated fur direct injection diesel engine. It was tested to estimate change of engine performance and exhaust emission characteristics for the commercial diesel fuel and oxygenate blended fuel which has three kinds of mixed ratio. And, it was tried to analyze not only total hydrocarbon but individual hydrocarbon components from Cl to C6 in exhaust gas using gas chromatography to seek the reason far remarkable reduction of smoke emission. This study was carried out by comparing the chromatogram with diesel fuel and diesel feel blended DGM(diethylene glycol dimethyl ether) 5%. The results of this study show that individual hydrocarbon(C1∼C6) as well as total hydrocarbon of oxygenated fuel is reduced remarkably than that of diesel fuel.

• YAKHAK HOEJI
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• v.3 no.1
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• pp.45-47
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• 1957

A paper chromatographical method is studied to detect As and Sb from a mixed sample applying the principle of Gutzeit's. After spoting the mixed $AsH_3$ sample on the $AgNO_3$ band of paper strip (6 mm $\times$ 300 mm of Whatman No.52 or Toyo No.2 filter paper), the strip is developed by ascending method using N-HCl solution as a developing soluvent. The color spot detection of As and Sb is done by exposing the dried chromatogram to $H_2S$ stream. According to the experiments, the detectable minimum range of As is 3 micrograms and that of Sb is 15 micrograms. The yellow phosphorous interfers to the color spot detection of As and Sb, so that, previously the most of yellow phosphorous from the sample should be removed out.

• YAKHAK HOEJI
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• v.3 no.1
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• pp.48-50
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• 1957

The micro-assay methods of vanillin have been shown quite few, though several methods have been introduced for determination. A new sensitive micro-determination of vanillin, applying the yellow color reaction of vanillin and anillin, is shown in this paper. The absorption maximum of the yellow coloring matter, 4-Oxy-3-methoxy-henzal aniline, was 435 mu. The one dimensional ascending paper chromatographic method is applyed for isolation of vanillin from the mixed sample. The microdetection of vanillin is studied only in this paper. Vanillin was detected by the yellow spot on paper trip by the coloring reagent of aniline after several hours paper strip chromatographic at the following condition; paper strip ................ 2.5 X 35cm Whatman Filter Paper No.2 developing Solvent ......... petroleum-benzene-methanol n-butanol-water coloring agent ............. aniline. The Rf-value on petroleum benzene and methanol was 0.63 and that on n-butanol and water was 0.90. The minimum detectable amount of vanillin by this method was 10 micrograms. It is recommendable, if interference substances as aromatic aldehydes present, that the application of this aniline reaction and Foline Denis reaction on the same paper chromatogram is appreciable.