• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제4권3호
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• pp.195-200
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• 2000

The kinetics of the reaction between carbonyl sulfide and aqueous monoethanolamine were studied over a range of temperature (298-348 K) and amine concentrations using a wetted-sphere absorber. The key physicochemical properties used to interpret the data included the solubility and diffusivity of the COS in the aqueous amine solution. The experimental data were interpreted using a zwitterion mechanism, which produced an Arrhenius plot with third-order kinetic rate constants. The fit of these data was $K_3$=$1.32\times10(sup)10exp(\frac{-6136}{T}}$

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2001년도 정기총회 및 봄 학술발표회 초록집
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• pp.64-67
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• 2001

• Bulletin of the Korean Chemical Society
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• 제16권2호
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• pp.112-120
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• 1995

The conformational study on malonic acid, hydrogen malonate, malonate, malonyl methyl sulfide, and malonyl methyl sulfide anion, as the model compounds of malonyl-CoA, was carried out using the semiempirical MO methods (MNDO, AM1, and PM3) and hydration shell model. On the whole, the feasible conformations of malonic acid, hydrogen malonate, and malonate seem to be similar to each other. In malonic acid and malonate, two carboxyl groups are nearly perpendicular to the plane of the carbon skeleton, despite of different orientation of two carboxyl groups themselves. In particular, two carboxyl groups of hydrogen malonate are on the plane formed by carbon atoms with an intramolecular hydrogen bond. The calculated results on the geometry and conformation of three compounds are reasonably consistent with those of X-ray and spectroscopic experiments as well as the previous calculations. The orientation of two carbonyl groups of malonyl methyl sulfide is quite similar to that of malonic acid, but different from that of its anion. Especially, the computed probable conformations of the sulfide anion by the three methods are different from each other. The role of hydration seems not to be crucial in stabilizing the overall conformations of malonic acid, hydrogen malonate, malonate, and malonyl methyl sulfide. However, the probable conformations of the unhydrated sulfide anion obtained by the MNDO and AM1 methods become less stabilized by including hydration. The AM1 method seems to be appropriate for conformational study of malonyl-CoA and its model compounds because it does not result in the formation of too strong hydrogen bonds and significant change in conformational energy from one compound to another.

• 한국식품저장유통학회지
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• 제7권1호
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• pp.33-37
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• 2000

Effects on keeping quality according to the different package environment in cabbage and brccoli were studied. Opened 2 mil LDPE (low density polyethylene) sealed 4 mil LDPE and BA(barrier polyethylene) were used as package films. Weight loss was markedly in opened 2 mil LDPE in cabbage and broccoli as 6 and 28%, respectively. Carbon dioxide was higher in seal-packaging cabbage and broccoli with BA held at 4 $^{\circ}C$ was above 15 and 31% within 15 days, respectively, while oxygen content was depleted to 2% or less after 10 days. The main difference between volatile sulfur-containing compounds produced from cabbage and broccoli were the relative quantities and rates of production of hydrogen sulfide, carbonyl sulfide, methanethiol and dimethyl disulfide in opened 2 mil LDPE , sealed 4 mil LDPE and barrier bags during storage.

• BMB Reports
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• 제43권9호
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• pp.622-628
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• 2010

Dimethyl sulfoxide (DMSO) can be reduced to dimethyl sulfide by MsrA, which stereospecifically catalyzes the reduction of methionine-S-sulfoxide to methionine. Our previous study showed that DMSO can competitively inhibit methionine sulfoxide reduction ability of yeast and mammalian MsrA in both in vitro and in vivo, and also act as a non-competitive inhibitor for mammalian MsrB2, specific for the reduction of methionine-R-sulfoxide, with lower inhibition effects. The present study investigated the effects of DMSO on the physiological antioxidant functions of methionine sulfoxide reductases. DMSO elevated hydrogen peroxide-mediated Saccharomyces cerevisiae cell death, whereas it protected human SK-Hep1 cells against oxidative stress. DMSO reduced the protein-carbonyl content in yeast cells in normal conditions, but markedly increased protein-carbonyl accumulation under oxidative stress. Using Msr deletion mutant yeast cells, we demonstrated the DMSO's selective inhibition of the antioxidant function of MsrA in S. cerevisiae, resulting in an increase in oxidative stress-induced cytotoxicity.

• 한국식품과학회지
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• 제9권2호
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• pp.116-122
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• 1977

김치의 휘발성(揮發性) 향미성분(香味成分)들에 관해서 확인(確認)하고 염도(鹽度) 및 숙성(熟成)에 따른 차이(差異)를 비교(比較)해 보았다. 김치를 고염(高鹽)김치, 저염(低鹽)김치, 저염(低鹽)날김치로 구분(區分)하고 침전반응(沈澱反應)을 통해 carbonyl화합물(化合物)과 함유황물질(含硫黃物質)의 존재(存在)를 확인(確認)하였다. Vacuum distillation하여 얻은 증류액(蒸溜液)을 ice+salt, dryice-acetone, liquid N trap에 각각 응축시킨 후(後). GC를 이용(利用)하여 분리(分離), 확인(確認)함으로써 다음과 같은 결과(結果)를 얻었다. (1) 날김치로부터 acetaldehyde, methylsulfide, propionaldehyde, acetone, methyl ethyl sulfide, methanol, ethyl sulfide, methyl ethyl ketone, ethanol, methyl allyl sulfide, methyl disulfide, allyl alcohol, allyl cyanide, allyl sulfide, allyl disulfide, allyl isothiocyanate, n-hexanol등 17가지를 잠정적으로 추정(推定)할 수 있었고, m.p. IR, UV, TLC, 관능검사(官能檢査)를 통해서 acetaldehyde, acetone, ethanol, ethyl sulfide의 4가지를 동정(同定)하였다. (2) 김치의 휘발성(揮發性) 향미성분(香味成分)으로서 가장 많은 량(量)을 차지하는 것은 ethanol이며 저염(低鹽)김치가 고염(高鹽)김치나 저염(低鹽) 날김치에 비해 월등히 많았다. (3) acetaldehyde는 고염(高鹽)날김치에는 상당량이 있었으나 숙성(熟成)된 김치에서는 매우 감소(減少)하였다. (4) 함유황물질(含硫黃物質)은 숙성(熟成)된 김치에서는 그 종류(種類)가 감소(減少)하였으며 이런 경향은 저염(低鹽)김치에서 현저하였다. (5) 김치가 숙성(熟成)되면 함유황물질(含硫黃物質)이나 acetaldehyde는 감소(減少)하고 ethanol과 그밖의 발효산물(醱酵産物)이 증가(增加)하여 김치의 휘발성(揮發性) 향미(香味)를 이룬다고 생각된다.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제4권4호
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• pp.241-247
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• 2000

This paper reports on an experimental study of the absorption of COS in a secondary amine diethanolamine. The primary objectives were to investigate an analogy between $N_2$O and COS, thereby allowing an estimation of the physical solubility and diffusivity of the sulfur gases in the reacting amine solutions. The solubilities and diffusivities of $N_2$O and COS in 5~25% aqueous polyethylene glycol at $25^{\circ}C$ were measured. The results appeared to verify the use of an $N_2$O-COS analogy for estimating the solubility and diffusivity of COS in aqueous solutions of alkanolamines up to an approximate 25 weight % concentration. The mean deviation of the $N_2$O analogy relative to the measured solubilities was 3.7%, and the mean deviation between the analogy and the measured diffusion coefficients using the experimental values for Hcos/PEG was 14.6%.

• Bulletin of the Korean Chemical Society
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• 제5권6호
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• pp.240-244
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• 1984

8-Oxyquinoline dihydroboronite is prepared by mixing equimolar amounts of 8-hydroxyquinoline and borane-dimethyl sulfide complex in tetrahydrofuran at room temperature and its structure is determined by spectroscopic methods. The reagent is shown to be an extremely mild reducing agent and reduces aldehydes, cyclohexanones, and acid chlorides to some extent. The reagent in the presence of 0.1 equiv of boron trifluoride etherate in tetrahydrofuran at room temperature reduces selectively aldehydes in the presence of ketones, while the reagent in the presence of 1 equiv of boron trifluoride etherate rapidly reduces simple aldehydes and ketones but does not reduce carboxylic acids, esters, and amides.

• 한국대기환경학회지
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• 제23권2호
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• pp.147-157
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• 2007

This study was carried out to investigate the characteristics of fourteen odor compounds from a total of 10 sampling sites in residential areas around Banwol-Sihwa industrial complex. The measurement data are analyzed and compared with sensation of odor unit. Only a hydrogen sulfide out of four sulfur compounds was quantified above the detection limit (0.06 ppb) in the residential area around Banwol industrial complex with leather companies and a sewage treatment plant. The concentrations of VOCs were higher than those measured from a big city, and styrene showed the relatively high concentration from all sampling sites ($2.1{\sim}37.8\;ppb$). In the case of carbonyl compounds, acetaldehyde was found most frequently with the mean of 3.97 ppb, and its concentration difference was not significant between Banwol and Sihwa industrial complex. Of the nitrogen compounds, ammonia was measured at the relatively high concentration from all the sampling sites ($12{\sim}707\;ppb$), and a trimethylamine was found at the odor threshold level (0.1 ppb). The concentrations of styrene and ammonia showed relatively seasonal variation, the concentration of styrene in summer was five times higher than that in autumn, the concentration of ammonia in autumn was two times higher than that in summer. However other odorous compounds did not show such strong seasonal variation. Odor-concentration relationship between odor unit and $H_{2}S$ concentrations from industrial sources was examined and used as odor sensation evaluation, and thus the neighbourhood odor complaints maybe caused during the four seasons from the results.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.460-460
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• 2012

반도체 Device가 Shrink 함에 따라 Pattern Size가 작아지게 되고, 이로 인해 Photo Resist 물질 자체만으로는 원하는 Patterning 물질들을 Plasma Etching 하기가 어려워지고 있다. 이로 인해 Photoresist를 대체할 Hard Mask 개념이 도입되었으며, 이 Hardmask Layer 중 Amorphous Carbon Layer 가 가장 널리 사용되고 지고 있다. 이 Amorphous Carbon 계열의 Hardmask를 Etching 하기 위해서 기본적으로 O2 Plasma가 사용되는데, 이 O2 Plasma 내의 Oxygen Species들이 가지는 등 방성 Diffusion 특성으로 인해, 원하고자 하는 미세 Pattern의 Vertical Profile을 얻는데 많은 어려움이 있어왔다. 이를 Control 하기 인해 O2 Plasma Parameter들의 변화 및 Source/Bias Power 등의 변수가 연구되어 왔으며, 이와 다른 접근으로, N2 및 CO, CO2, SO2 등의 여러 Additive Gas 들의 첨가를 통해 미세 Pattern의 Profile을 개선하고, Plasma Etching 특성을 개선하는 연구가 같이 진행되어져 왔다. 본 논문에서 VLSI Device의 Masking Layer로 사용되는, Carbon 계 유기 층의 Plasma 식각 특성에 대한 연구를 진행하였다. Plasma Etchant로 사용되는 O2 Plasma에 새로운 첨가제 가스인 카르보닐 황화물 (COS) Gas를 추가하였을 시 나타나는 Plasma 내의 변화를 Plasma Parameter 및 IR 및 XPS, OES 분석을 통하여 규명하고, 이로 인한 Etch Rate 및 Plasma Potential에 대해 비교 분석하였다. COS Gas를 정량적으로 추가할 시, Plasma의 변화 및 이로 인해 얻어지는 Pattern에서의 Etchant Species들의 변화를 통해 Profile의 변화를 Mechanism 적으로 규명할 수 있었으며, 이로 인해 기존의 O2 Plasma를 통해 얻어진 Vertical Profile 대비, COS Additive Gas를 추가하였을 경우, Pattern Profile 변화가 개선됨을 최종적으로 확인 할 수 있었다.