• Proceedings of the Culinary Society of Korean Academy Conference
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• 2005.10a
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• pp.61-86
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• 2005

Kimchi power made by kimchi fermentation and freeze-drying was added to Western foods of sauce, soup, pizza, cracker and bread. Flavor qualities of the processed fusionfoods were evaluated by analyzing volatile compounds and sensory evaluation. The optimum condition of kimchi fermented for the best flavor quality of freeze-drying was the ranges of pH4.0${\sim}$pH4.7 and acidity 0.5${\sim}$0.8. The number of volatile compounds identified from extracts of the freeze-dried kimchi powder was 24, which contained 7 alcohols, 5 esters, 5 acids, 3 sulfur-containing compounds, 2 aldehydes, 1 oxygen-containing and 1 other. Among the identified compounds, the most abundant compound was eugenol(39.40%), followed as the order of dodecanoic acid(4.91%), acetic acid(1.70%), methyl 2-propenyl disulfide(1.52%), hexanal(1.51%) and 2-pentylfuran(1.18%). These compounds affected the flavor quality of kimchi powder.

• Korean Journal of Microbiology
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• v.18 no.4
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• pp.155-160
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• 1980

Microorgansims utilizing anionic detergent as their carbon and sulfur sources were isolated from soils and sewages. Alkyl benzene sulfonate (Hiti) and sodium dodecyl sulfonate (SDS) were the detergent compound tested. Three of these isolated microorganisms were identified as Pseudomonas spp. and the others asKlbsiella, Enterobacter and Acinetobacter. Biodegradation rate of the detergents and growth rate of Acinetobacter Strain II-8, Pseudomonas strain H-3-1 and 554 among six isolated microorganisms were investigated with colorimetric, warburg manometric, and ultraviolet absorption analyses. By performance of 4 serial successive tranfer to new culture broth for the purpose of adaptation method, ABS and SDS could be degraded to far more than 40%-60% and 70%-75%, respectively. However the employment of nonadaptation method, ABS and SDS were degraded to 30%-45% and 45%-65%, respectively. In another words, detergents degradation ability was increased to a certain extent by successive transfer to the new minimal media. We would conclude that the development of adaptation was effective in the removal of recalcitrant compounds.

• Bulletin of the Korean Chemical Society
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• v.11 no.1
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• pp.60-64
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• 1990

The reactions of alkanesulfonyl chlorides with pyridines in the presence of various solvents have been studied by means of kinetic method. Alkanesulfonyl chlorides bearing ${\alpha}$-hydrogen with the normal attack of pyridine is found to be at the ${\alpha}$-hydrogen with elimination to form the sulfene intermediate evidently. From the mass spectra by the reaction of ethanesulfonyl chloride with 3-picoline in the presence of methanol-$d_1$, it has shown that the reaction has a witness favorable to the slulfene intermediate.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.03a
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• pp.427-430
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• 2008

Electroforming is one of the key technologies for the regenerative thrust chamber of the rocket engine. To use nickel electroforming method for the thrust chamber, direct electroforming of nickel on cupper and the welding method between different materials are needed. Minimizing the internal stress is one of the important factor for making thick electroforming,. Also minimizing contamination(ex. Sulfur containing compound) is another important factor for the stability of quality. This paper includes advanced methods for thick nickel electroforming, those of strength test results and EDS/EPMA inspection results. Advanced for electroforming process makes the achievement of Electro-beam welding between Inconel718(Manifold) and Nickel Electroforming. This paper also includes the influence of the electroforming precipitation angle on strength. Thus advanced electroforming improvement processes and the test results make achievement for manufacturing of the regenerative thrust chamber with direct nickel thick electroforming on cupper materials.

• Bulletin of the Korean Chemical Society
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• v.13 no.3
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• pp.311-314
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• 1992

A new monocyclic ${\beta}-lactam$ analogue, sodium (3R,4S)-3-[2-(2-aminothiazol-4-yl)-(Z)-2-methoxyi minoacetamido]-4-methoxymethyl-2-azetidinone-1- sulfonate (3) was synthesized from L-aspartic acid. Starting from L-aspartic acid, (S)-1-benzyl-4-benzyloxycarbonyl-2-azetidinone (7) was synthesized in four steps by following the established procedures and converted into (3R,4S)-3-amino-1-t-butyldimethylsilyl-4-methoxym ethyl-2-azetidinone (13) in six steps. Acylation of the amino group of 13 with $2-amino-{\alpha}$ -(methoxyimino)-4-thiazoleacetic acid, desilylation, and sulfonation with sulfur trioxide-pyridine complex followed by ion exchange afforded sodium (3R,4S)-3-[2-(2-aminothiazol-4-yl)-(Z)-2-methoxyi minoacetamido]-4-methoxymethyl-2-azetidinone-1- sulfonate (3). Antibacterial activities of this ${\beta}$ -lactam compound 3 were, however, found to be quite low compared to cefotaxime.

• Applied Chemistry for Engineering
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• v.21 no.1
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• pp.104-110
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• 2010

Deactivation of SCR catalysts applied in coal, orimulsion, and LNG power plants in Korea were studied for the regeneration of the deactivated catalyst. The catalysts were characterized by XRD, ICP-AES, BET and SEM, and were examined for ammonia SCR. Deactivation of SCR catalyst applied in coal power plant was mainly caused by the blockade of the pore due to the deposition of sulfate and particulate related to the ingredients of the fuel. The surface area of SCR catalyst applied in orimulsion power plant decreased considerably by the accumulation of the compounds of vanadium, sulfur, and magnesium on the surface of the catalyst. The compounds of vanadium and sulfur were related to the ingredients of the fuel, and the compound of magnesium was related to the additive of the fuel. The activity of the deactivated catalyst for ammonia SCR, however, decreased slightly. Despite the long use for more than two-year, deactivation of SCR catalyst applied in LNG power plants hardly occurred.

• Journal of Korean Society for Atmospheric Environment
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• v.23 no.1
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• pp.39-49
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• 2007

In this study, the performance characteristics of solid phase microextraction (SPME) were investigated for three major odorous groups that consist of 10 individual compounds ([1] volatile organic compounds (VOC): benzene, toluene, p-xylene and styrene, [2] reduced sulfur compounds (RSC): hydrogen sulfide, methyl mercaptan, dimethylsulfide (DMS), dimethyldisulfide (DMDS), and carbon disulfide, and [3] amine: trimethylamine (TMA)). For the purpose of a comparative analysis, two types of SPME fiber ([1] polidimethylsiloxane/divinilbenzene (P/D) and [2] $Carboxen^{TM}$/polidimethylsiloxane (C/P)) were test ε d against each other for a series of standards prepared at different concentration levels (100, 200, and 500 ppb). To compare the analytical performance of each fiber, all standards were analyzed for the acquisition of calibration data sets for each compound. The results of P/D fiber generally showed that its calibration slope increased as a function of molecular weight across different VOCs; however, those of C/P fiber showed a fairly reversed trend. Besides, we confirmed that the application of SPME is limited to many sulfur compounds; only two compounds (DMS and DMDS) are sensitive enough to draw calibration results out of SPME. The calibration data for RSC show generally enhanced slop values for C/P relative to P/D fiber. However, in the case of TMA, we were not able to find a notable difference in their performance.

• Journal of Korean Society for Atmospheric Environment
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• v.27 no.1
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• pp.1-15
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• 2011

Korea Global Atmosphere Watch Center (KGAWC), which is located in Anmyeondo and, belongs to the Korea Meteorological Administration (KMA), measures sulfur hexafluoride ($SF_6$) in every hour since 2007. In this study, $SF_6$ observed in 2007 are discussed. A gas chromatograph-electron capture detector (GC-ECD) with pre-cooled device is applied during the observation, and produced data are qualified by means of periodic calibration with $SF_6$ standard gas made by Korea Research Institute of Standard and Science (KRISS). $SF_6$ has been greatly paid attention since Kyoto protocol because of its high global warming potential(GWP) with 22,200 times of $CO_2$ in the period of 100 years. It is a man-made compound and has been usually used for gas insulation since 1970s and for etching process in the information technology-based industry since 1990. Average mixing ratio of $SF_6$ in 2007 was 6.65 pmol/mol at Anmyeondo. According to the GAW report published in 2008, average mixing ratio of $SF_6$ in the atmosphere is continuously growing. At present, the average mixing ratio of $SF_6$ in the atmosphere is known to be approximately 6.25 pmol/mol at global observatory. $SF_6$ value in Anmyeondo shows 0.40 pmol/mol greater than that of the Mauna Loa observatory in 2007.

• Journal of Periodontal and Implant Science
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• v.34 no.2
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• pp.449-459
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• 2004

Bacterial byproducts and volatile sulfur compounds(VSC) have been found to be the leading intra-oral agents, specifically, the byproducts of gram negative anaerobic bacteria have been implicated as primary factors of halitosis in patients presenting with periodontal disease. The objective of this study was to determine the correlation between periodontal treatment and the subsequent reduction in the level of halitosis. Forty-three subjects presenting with periodontal disease were examined before periodontal treatment, one week after treatment, one month after treatment, and finally, two months after treatment, using a portable sulfide monitoring $Halimeter^{(R)}$ to measure the VSC concentrations at the prescribed intervals. The results of the study were as follows: 1. Significant decreases in the mean VSC concentration were observed at the one week, one month, and two month post-op intervals relative to the pre-op measurement. (p<0.05) 2. Significant decreases in the mean VSC concentration were observed in subjects after completion of flap operations. Significant decreases in the mean VSC concentration were observed at the one and two month post-flap operation measurement relative to the VSC concentration at one week (p<0.05), but no significant differences between the one month and two month VSC concentrations were found. (p<0.05) 3. Significant decreases in the mean VSC concentration were observed in subjects after completion of subgingival curettage (p<0,05). Significant decreases were found between the one week and one month measurements and between the one month and two month measurements, but significant differences were not observed between the one week and two month measurements. (p<0.05) The results of this study show significant decreases in VSC concentration in test subjects after periodontal treatment. It can be inferred from the results above, that periodontal disease is a significant contributing factor of halitosis, and that treatment of periodontal disease can been an effective means of reducing VSC concentration in patients presenting with halitosis concurrent with periodontal disease.

• Journal of Ginseng Research
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• v.34 no.2
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• pp.122-131
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• 2010

This clinical study was performed to evaluate whether supplementation of proton pump inhibitor (PPI)-based triple therapy with Korean red ginseng can enhance Helicobacter pylori (H. pylori) eradication and reduce levels of halitosis-associated volatile sulfur compounds (VSCs) in the stomach. Seventy-six patients were randomized into an eradication regimen-only group (n=45) or an eradication regimen plus 10 weeks of Korean red ginseng supplementation group (n=31). The eradication regimen consisted of PPI b.i.d., clarithromycin 500 mg b.i.d., and amoxicillin 1 g b.i.d.. for seven days. Korean red ginseng supplementation commenced on the last day of the eradication regimen. $^{13}C$-urea breath test and halimeter measurements were performed prior to protocol repetition. By intention-to-treat analysis, the H. pylori eradication rate in the Korean red ginseng group (77.4%, 24 of 31) was higher than that in the control group (45.0%, 26 of 45). However, by per protocol analysis, the eradication rate in the Korean red ginseng group was significantly higher than that in the control group (92.3%, 24/26 vs. 69.4%, 26/38; p<0.05). H. pylori infection was significantly associated with increased VSC levels. However, VSC levels decreased significantly in the Korean red ginseng group (p<0.05). In conclusion, supplementation of triple therapy with Korean red ginseng increased the H. pylori eradication rate and led to significant reductions in VSC levels, suggesting the usefulness of this substance in combating H. pylori infection.