• 한국해양학회지
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• v.20 no.1
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• pp.74-82
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• 1985

Exposed on the sea, the oils are affected by the combined effects of evaporation, solution, chemical oxidation, and biological decomposition. Therefore the samples were taken after artificial weathering, and they were analyzed by gas chromatography for sulfur and hydrocarbons. The measurement results of gas chromatography have shown characteristic patterns. The peaks of the lower hydrocarbons in pollutant oil decreased with time. But the chromatograms for sulfur compound analysed by FPD showed little changes with lapse of time. The hydrocarbon and sulfur compound analysis by gas chromatography can be effectively used for analyzing oils for comparative identification.

• Aerospace Engineering and Technology
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• v.11 no.2
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• pp.26-32
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• 2012

The purpose of this paper is to present the summary of trouble shooting result on the dendrite defect of SSM(Second Surface Mirror) which is one of major thermal control elements for satellite. Through this failure analysis on SSM dendrite, it is found that the dendrite defect may happen to silver coated layer of SSM if SSM is directly exposed to the environment containing sulfur or chlorine compound. As a preventive action, it is required that SSM shall not contact directly with rubber pad containing sulfur compound.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.3
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• pp.332-341
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• 2007

The purpose of this study was to investigate the change of flavor compounds of freeze-dried garlic and garlic roasted with soybean oil and sesame oil. Freeze-dried garlic and ground raw garlic roasted with oils was prepared at $180^{\circ}C$ for 5 minutes. Volatile compounds of garlic samples were obtained by Likens-Nickerson distillation/solvent extraction and identified by GC and GC/MS. Sulfur compounds, methyl allyl sulfide, diallyl sulfide, methyl allyl disulfide, dimethyl trisulfide, diallyl disulfide, methyl allyl trisulfide and diallyl trisulfide were the major volatile in garlic flavor which was more than 98% of the total volatile compounds. The total amount of sulfur compounds in freeze-dried garlic roasted with soybean oil was decreased to 20% compare to that of garlic flavor; however, 10 pyrazines such as 2-methyl pyrazine, 2,6-dimethyl pyrazine, 2-ethyl-5-methyl pyrazin and 3-ethyl-2,5-dimethyl pyrazine which were not originated from both freeze-dried garlic and soybean oil were identified. They might be generated from thermal interactions of sugars and nonvolatile flavor precursors of garlic. In freeze-dried garlic roasted with sesame oil, the amount of diallyl sulfide, methyl allyl disulfide, dimethyl trisulfide increased whereas diallyl disulfide completely disappeared. The amount of two cyclic compounds 3,4-dihydro-3-vinyl-1,2-dithiin and 2-vinyl-4H-1,3-dithiin, which were artifacts from allicin, increased in roasted garlic with sesame oil.

• Proceedings of the KSEEG Conference
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• 2002.04a
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• pp.59-61
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• 2002

• Journal of the Korean Ceramic Society
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• v.11 no.4
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• pp.31-36
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• 1974

For gold balsam, the suitable sulfur balsam which is made of lavender oil and sulfur is found to be the distillate with the content of 15~19% sulfur. The sulfur balsam is distillated under 20mmHg vaccum at 84~105$^{\circ}C$. The composition of the compound which is produced by reaction between sulfur balsam and gold chloride is recognized as C10H18SAuCl3. This varys to C10H18SAuCl in water. The reaction constants K from C10H18SAuCl3 to C10H18SAuCl at 30, 40, 5$0^{\circ}C$ are as followsr. K1=7.97~9.28$\times$10-2 K2=2.81~3.79$\times$10-1 K3=4.74~6.74$\times$10-1 The plots of T versus log K are linear, which shows pseudo-first order reaction. The lower temperature is, the more stable C10H18SAuCl3 is. The gold balsam with excess sulfur balsam is increased in stability.

• Korean Journal of Food Science and Technology
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• v.5 no.1
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• pp.55-64
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• 1973

Garlic and traditional fovarite foodstuffs of plant origin have been analyed for selenium and sulfur containing amino acid content selenium compound were assayed using a $^{77m}Se$ neutron activation analysis, cystine and methionine determination by paper and thin-layer chromatography. The results obtained indicate that the content of selenium and sulfur containing amino acid are highest in garlic. The results also show that the selenium is a more abundant in particular speies such as garlics produced in Tan Yang and Wei Sung. The effect of Korean garlic and favorite typically found in the Korean diet has also been studied. Some vegetables known to contain a relatively high level of sulfur and selenium (garlic and onion) do loss significent quantities of selenium as a result of cooking.

• Journal of the Korean Electrochemical Society
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• v.24 no.3
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• pp.42-51
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• 2021

Dissociation into Lithium-polysulfide electrolyte due to repeated cycles during the Lithium/Sulfur battery reaction is a major problem of reduced battery lifespan. We searched for a porous carbon with a large specific surface area that infiltrated S to prevent liquid Lithium-polysulfide from being dissolved in electrolyte, induce adsorption of Lithium-polysulfide, and further increase conductivity. In order to obtain porous carbon spheres with a large specific surface area, the carbon spheres of 1939 m²/g were raised to 2200 m²/g through additional KOH treatment. In addition, through heat treatment with S, a carbon sulfur compound containing 75 wt% of S was fabricate and material analysis was conducted on the possibility of using the cathode material. The electrochemical characteristics of the Reference (622; sulfur: 60%, conductive material: 20%, binder: 20%) pouch cell and the pouch cell made using 75wt% of carbon sulfur compound were analyzed. 75wt% of carbon sulfur pouch cell showed a 20% increase in lifespan and 10% improvement in C-rate compared to the Reference pouch cell after 50 cycles.

• Journal of the Korean Society of Combustion
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• v.1 no.1
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• pp.31-39
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• 1996

An equilibrium analysis was carried out to determine principal species in the incineration of hazardous waste, which was assumed as a compound of hydrocarbon fuel, chlorine, sulfur, and heavy metals, and their behaviors with variation of temperature, chlorine and sulfur concentrations. Calculated results showed that the most important parameter influencing the principal species was temperature. Chlorine concentration affected on mole fractions of the species, especially at high temperature. Existence of sulfur had a significant effect on the species at low temperature, regardless of surfur concentration. Generally, principal species at high temperature were chlorides and oxides, while the principal species at low temperature were sulfides. As temperature increased, mole fractions of the principal species increased at low temperature, however, mole fractions of some metal species decreased at high temperature.

• International Journal of Automotive Technology
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• v.4 no.2
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• pp.95-100
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• 2003

Automobile industry has been developed rapidly as a key manufacturing industry in Korea. Meanwhile, air pollution is getting worse noticeably than ever. In the diesel emission, PM (Particulate Matter) and NOx (Nitrogen Oxides) have been exhausted with a great amount and the corresponding emission regulations are getting stringent. In order to develop low emission engines, it is necessary to research on better qualified fuels. Sulfur contained in fuel is transformed to sulfur compound by DOC (Diesel Oxidation Catalyst) and then it causes to the increase of sulfate-laden PM on the surface of catalyst. In this research, ULSD (Ultra Low Sulfur Diesel) is used as a fuel and some experimental results are investigated. ULSD can reduce not only PM but also gas materials because cetane value, flash point, distillation 90%, pour point and viscosity are improved in the process of desulfurization. However, excessively reduced sulfur may cause to decease lubricity of fuel and engine performance in fuel injection system. Therefore, it requires only modest adjusted amount of sulfur can improve engine performance and DOC, as well as decrease of emission.

• Proceedings of the Korean Vacuum Society Conference
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• 1996.06a
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• pp.108-108
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• 1996