• Environmental Analysis Health and Toxicology
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• v.18 no.3
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• pp.193-197
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• 2003

슬러지로부터 발생하게 되는 인체에 유해하고 독성이 강한 악취물질들은, 대다수 슬러지내의 단백질, 탄수화물등의 물질들이 미생물의 호기성 및 혐기성 분해과정을 통해서 생성되는 유ㆍ무기 물질들을 포함하게 된다. 슬러지로부터 발생하는 주된 악취물질로서 hydrogen sulfide, methanethiol, dimethyl sulfide, dimethyldisulfide,dimethyltrisulfide등이 발견되어졌는데 이 다섯 종의 악취물질들은 모두가 황을 포함하는 물질들이다. 본 논문에서는 인체에 유해한 슬러지 악취의 강도 및 세기를 결정하고 비교하는 데 이용되어 질 수 있는 odor index(ODI)라는 방식이 제시되어졌다. 세가지 종류의 슬러지, 즉 hypochlorite 용액으로 처리한 슬러지와 향수 물질로 처리한 슬러지 및 아무런 처리를 하지 않은 슬러지 세 종류를 대상으로 30일이 넘는 기간동안 인체에 유해한 악취물질들에 대한 누적 odor index(ODI)값을 생성하여 비교하였다. 아무런 처리를 하지 않은 슬러지에서 가장 높은 odor index(ODI)값들이 나타났으며, 이것은 슬러지 처리에 있어서 심각한 단기 및 장기적인 유해 악취발생 문제가 야기될 수 있음을 나타낸다. 이에 대하여 hypochlorite용액으로 처리한 슬러지로부터는 인체에 유해한 악취 발생을 처리 즉시부터 30일이 넘는 기간동안 측정한계치 이하 단계로 낮출 수 있었다.

• 한국가스학회:학술대회논문집
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• 1999.09a
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• pp.215-220
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• 1999

• Bulletin of the Korean Chemical Society
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• v.3 no.2
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• pp.81-82
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• 1982

Lithium n-butylborohydride generated from n-butyllithium and borane-dimethyl sulfide complex in equimolar ratio in toluene-n-hexane is exceedingly effective for selective 1,2 reductions of enones.

• Bulletin of the Korean Chemical Society
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• v.10 no.2
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• pp.219-220
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• 1989

• Bulletin of the Korean Chemical Society
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• v.34 no.3
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• pp.777-782
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• 2013

In order to further reduce the sulfur content in liquid hydrocarbon fuels, a desulfurization process by adsorption for removing dimethyl sulfide (DMS) and propylmercaptan (PM) was investigated. Bentonite adsorbents modified by $CuCl_2$ for the desulfurization of model oil was investigated. The results indicated that the modified bentonite adsorbents were effective for adsorption of DMS and PM. The bentonite adsorbents were characterized by X-ray diffraction (XRD) and thermal analysis (TGA). The acidity was measured by FT-IR spectroscopy. Several factors that influence the desulfurization capability, including loading and calcination temperature, were studied. The maximum sulfur adsorption capacity was obtained at a Cu(II) loading of 15 wt %, and the optimum calcination temperature was $150^{\circ}C$. Spectral shifts of the ${\nu}$(C-S) and ${\nu}$(Cu-S) vibrations of the complex compound obtained by the reaction of $CuCl_2$ and DMS were measured with the Raman spectrum. On the basis of complex adsorption reaction and hybrid orbital theory, the adsorption on modified bentonite occurred via multilayer intermolecular forces and S-M (${\sigma}$) bonds.

• Journal of the East Asian Society of Dietary Life
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• v.16 no.3
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• pp.299-307
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• 2006

Raw whole garlic was pickled in two different ways, in soy sauce and in brine, to test the change of flavor compounds with aging period. The changes of pH, acidity, hardness and flavors were measured, accompanied with sensory evaluation. The pH of whole garlic in soy sauce and in brine was decreased as the aging period increased. The acidity was increased as pH decreased. Hardness tended to decrease as the aging time increased. For whole garlic in soy sauce and in brine, trans propenyl methyl disulfide, allyl methyl trisulfide, diallyl trisulfide, dimethyl trisulfide, allyl- 2,3-epoxypropyl sulfide, and 2-methyl-l,3-dithiane were increased as the aging proceeded but allyl methyl disulfide and diallyl disulfide tended to decrease. Hardness through the sensory evaluation decreased as the aging time increased. When the overall quality was compared between whole garlic in soy sauce and in brine after 60 days, the latter could be better estimated. Pickled garlic increased the flavor compounds such as trans propenyl methyl disulfide, allyl methyl trisulfide, diallyl trisulfide, dimethyl trisulfide, allyl-2,3-epoxypropyl sulfide, and 2-methyl-l,3-dithiane as the aging proceeded. Therefore, the above flavor compounds are considered as the major ingredients of the characterized flavor of pickled garlic.

• Journal of the Korean Society of Food Culture
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• v.25 no.5
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• pp.607-614
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• 2010

Changes in major volatile odor components (VOC) and sensory properties of kimchi during ripening for 4 days were investigated, and major VOCs of the raw materials of kimchi were also analyzed. Seven of eight major VOCs of kimchi originated mainly from garlic, while one originated from ginger. During 4 days of kimchi ripening, the amount of ethanol, which was substantially higher than that of other VOCs, increased continuously but decreased slightly on the fourth day. The amount of diallyl disulfide decreased during ripening, while that of allyl mercaptan decreased on the first day and increased slightly thereafter. The amount of methyl allyl sulfide, diallyl sulfide, and methyl trisulfide increased continuously during ripening, while that of dimethyl disulfide and methyl propyl disulfide increased until the second day and decreased thereafter. Scores of overall acceptability, taste, and odor for kimchi ripened for 2 days were significantly higher than those of other samples (p<0.05). The correlation between scores of overall acceptability and the amount of dimethyl disulfide or methyl propyl disulfide was higher than that of other VOCs.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.2
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• pp.230-235
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• 2005

Volatile organic components from fresh and freeze-dried onions were extracted by SDE apparatus and analyzed by GC/MS. Components of 40 and 31 were identified in fresh and freeze-dried onions respectively. These components included esters, aldehydes, ketones, alcohols and S-containing compounds. Major compounds of S-containing compounds such as 1-propanethiol, dipropyl trisulfide, and methyl propyl trisulfide in fresh onions were clearly decreased in freeze-dried onions. Then, S-containing compounds such as methyl allyl sulfide, propyl ally sulfide, dially disulfide and 3,5-diethyl-l,2,4-trithiolane and alcohols such as pentanol, hexanol and propanol were disappeared by freeze-drying. Exceptionally, ethyl acetate, dimethyl disulfide and 2-methyl-2-pentenal were increased as different trend with major S-containing compounds. (Z)-Propenyl methyl disulfide and (E)-propenyl methyl disulfide were also changed by freeze-drying in the similar pattern as mentioned above compounds.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.8
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• pp.541-548
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• 2012

The objective of this study was to investigate emission characteristics of odorous compounds from the pneumatic waste collection plants (namely, A and B sites). The air samples were collected from each site, at a carrier gas inside the plant and an exhaust gas, to analyze complex odor and 22 odorous compounds. Ammonia, sulfur compounds, and acetaldehyde were the critical odorous components generated in the plants studied. Characteristics of odor at exhaust outlet varied according to the type of odor control engineering. In the analysis of the odor contribution degree of odor components based on odor threshold, site A shows that the odor contribution of dimethyl sulfide was found to be 26%, acetaldehyde 18%, and methyl mercaptan 14%. For site B, methyl mercaptan was 56% and both hydrogen sulfide and dimethyl sulfide were 15%.

• Journal of Environmental Science International
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• v.11 no.8
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• pp.819-827
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• 2002

Laboratory scale experiments were conducted to evaluate the performance of a biofilter for eliminating dimethyl sulfide(DMS). A commercial compost/pine bark nugget mixture served as the biofilter material for the experiments. The gas flow rate and DMS concentration entering the filter were varied to study their effect on the biofilter efficiency. The operating parameters, such as the residence time, inlet concentration, pH, water content, and temperature, were all monitored throughout the filter operation. The kinetic dependence of the DMS removal along the column length was also studied to obtain a quantitative description of the DMS elimination. High DMS removal efficiencies(>95％) were obtained using the compost filter material seeded with activated sludge. DMS pollutant loading rates of up to 5.2 and 5.5 g-DMS/m$^3$/hr were effectively handled by the upflow and downflow biofilter columns, respectively. The macrokinetics of the DMS removal were found to be fractional-order diffusion-limited over the 9 to 25 ppm range of inlet concentrations tested. The upflow column had an average macrokinetic coefficient(K$\_$f/) of 0.0789 $\pm$ 0.0178 ppm$\^$$\sfrac{1}{2}$//sec, while the downflow column had an average coefficient of 0.0935 $\pm$ 0.0200 ppm$\^$$\sfrac{1}{2}$//sec. Shorter residence times resulted in a lower mass transfer of the pollutant from the gas phase to the aqueous liquid phase, thereby decreasing the efficiency.