• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.261-264
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• 2003

We try to distribute air pollution sources at target area. The complex method is used to distribute air pollution sources. Most of people, However, want to simple indicator as standard for express air pollution source. In many area, air pollution is caused by different types of sources. The general type is point source, such as tall stack of power plants and oil refineries stacks. A second type is areal source, such as local industry and transportation. In this aspect, the ratio of sulfur dioxide to nitrogen oxides (RSN =SO$_2$/NOx)is an indicator of air pollution source. the role of this ratio is to show the characteristics at target area of the relationship the point and the areal source. (omitted)

• Elastomers and Composites
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• v.22 no.4
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• pp.314-323
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• 1987

A blend ratio of rubber vulcanzates comprising NBR, CR, EPDM, NR, BR, and SBR alone or blended is determind through a P.G.C. It is found that a characteristic peak of elastomer is proportional to the content of each elastomer when they are pyrolysed. It is also classified to the different AN content in NBR vulcanizates, identification of sulfur-modified and non-sulfur bearing CR polymers, and the content of ethylene, propylene monomer and the third monomer in EPDM vulcanizetes.

• Journal of Environmental Science International
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• v.22 no.8
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• pp.1019-1027
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• 2013

Sulfur hexa-fluoride has been used as a etching gas in semiconductor industry. From the globally environmental issues, it is urgent to control the emissions of this significant greenhouse gas. The main objective of this experimental investigation was to find the effective catalyst for $SF_6$ decomposition. The precursor catalyst of hexa-aluminate was prepared to investigate the catalytic activity and stability. The precursor catalyst of hexa-aluminate was modified with Ni to enhance the catalytic activities and stability. The catalytic activity for $SF_6$ decomposition increased by the addition of Ni and maximized at 6wt% addition of Ni. The addition of 6wt% Ni in precursor catalyst of hexa-aluminate improved the resistant to the HF and reduced the crystallization and phase transition of catalyst.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.22 no.5
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• pp.213-217
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• 2012

Carbon coils could be synthesized on nickel catalyst layer-deposited silicon oxide substrate using $C_2H_2$ and $H_2$ as source gases under thermal chemical vapor deposition system. By the incorporation of $SF_6$ additive in cyclic modulation manner, the dominant formation of the nanosized carbon coils could be achieved with maintaining the minimized sulfur additive amount. The geometry variation of the as-grown carbon coils, such as linear type, microsized coil type, wavelike nanosized coil type, and nanosized coil type, were investigated according to the different cyclic modulation manner of $SF_6$ flow. $SF_6$ gas incorporation develops the coil-type geometry. Furthermore, the higher flow rate of $SF_6$ gas increased the amount of the nanosized carbon coils. The slightly increased etching ability by $SF_6$ addition seems to be the cause for these results.

• Carbon letters
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• v.1 no.1
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• pp.31-35
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• 2000

[ $SO_2$ ]and NO gases that come from the flue gases of most of all industrial combustion processes are harmful to everything include person and industrial facilities. For the simplification of the environmental clean-up processes, we studied the decomposition process by microwave. The microwave can destroy molecules into elementary atoms and offers energy to the atoms to react with carbons. Since the microwave is not absorbed into quartz tube and metallic chamber, the air pollution gases can be removed with much lower energy than in the case of conventional methods. We studied the decomposition of $SO_2$ and NO gases on the carbon beds by microwave. In the microwave field, the gases can be decomposed to form other compounds, such as elementary sulfur, nitrogen, carbon monoxide and carbon dioxide. It was found that CO gas is formed at higher temperature than is $CO_2$ gas, so it needs to control the bed temperature depend on products that we want to get.

• Journal of the Korean Chemical Society
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• v.19 no.3
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• pp.193-197
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• 1975

In the combustion process, it is found that the addition of small amount of hydroxide of alkali and alkaline earth metal to the anthracite is more effective in order to suppress the evolution of $SO_2 gas, since the large portion of sulfur contained in anthracite is remained in the ash with a form of sulfide and sulfate. Under this experimental condition, however, it was observed that the SO_2$ gas corresponding to about 20 % of sulfur content in anthracite was released at $1000^{\circ}C$.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.25 no.5
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• pp.205-211
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• 2015

Most of the sulfur is obtained from desulfurization of natural gas and crude oil. In Korea, more than 120 tons of sulfur are produced by refinery, and about 50 % of the produced sulfur is used as a raw material for the production of fertilizer and sulfuric acid. Modified sulfur is manufactured from excessive sulfur that could be used to improve concrete properties, and this study evaluated concrete strength and durability that contains modified sulfur. Flexural and compressive strengths of concrete with sulfur modified polymer were comparable to those of OPC concrete with mixing water at similar temperatures, while the strengths increased a little as mixing water temperature increased. It was also confirmed that the resistance to freeze-thaw damage was more dependent on entrained air characteristics obtained by a proper use of air entraining agent than on the use of sulfur modified polymer. When concrete was immersed in 5 % sulfuric acid, the rate of reduction in compressive strength of OPC concrete was less than 1/4 of the strength reduction of concrete with sulfur modified polymer. Also, the resistance of concrete with sulfur modified polymer to scaling due to the use of de-icing salt was evaluated as Class 1, while that of OPC concrete was evaluated as Class 4, as aggregates were exposed. Accordingly, it is believed that sulfur modified polymer could be effectively used for bridge deck concrete since sulfur modified polymer improves the durability of concrete.

• YAKHAK HOEJI
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• v.28 no.1
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• pp.25-27
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• 1984

Some $\betha$-lactam antibiotics-penicillins and cephalosporins-were determined by gas chromatography (GC) with flame photometric detector (FPD) which was selective and sensitive to sulfur-containing compounds. Methyl ester derivatives of carboxyl group in $\betha$-lactam antibiotics were prepared using 0.5Mmethyl iodide in methylene chloride and were taken for gas chromatography with 0.9% or 0.6% QF-1 on Chromosorb WAW-DMCS. We have found that it is possible to determine methyl esters of $\betha$-lactam antibiotics by GC/FPD.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2003.11a
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• pp.17-20
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• 2003

• Korean journal of food and cookery science
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• v.17 no.1
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• pp.55-59
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• 2001

To investigate the usefulness of Allium senescens as a aromatic edible plant, volatile flavor components and flavor pattern were analyzed. Essential oils of fresh and freeze dried Allium senescens were extracted by SDE(simultaneous steam distillation and extraction) method using diethyl ether as solvent. And their volatile flavor components were analyzed by gas chromatography(GC) and gas chromatography-mass spectrometry (GC-MS). A total of 46 components, including 11 hydrocarbons, 9 aldehydes, 4 alcohols, 2 esters, 7 acids, 4 ketones and 9 sulfur containing compounds were identified in fresh Allium senescens. In freeze dried Allium senescens, 8 hydrocarbons, 5 aldehydes, 3 alcohols, 5 esters, 2 acids, 3 ketones and 4 sulfur containing compounds were identified. Volatile flavor patterns of Chinese chive and Allium senescens were compared using electronic nose. The score of first principal component was significantly different in Allium senescens and Chinese chive.