• Journal of environmental and Sanitary engineering
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• v.11 no.2
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• pp.65-73
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• 1996

The objective of this study is to investigate the removal efficiency of volitile organic compounds in soil, and the mechanism of desorption by bench scale microwave heating, Silt soil used for experiment and was impregnated with toluene, tetrachloroethylene, o-xylene and p-dichlorobenzene and the microwave treatment was conducted in a modified domestic microwave oven : 2450MHz, 700W. According to the results of the research the removal efficiency was improved with increasing water contents and the soil temperature appeared to plateau period extending to 2-3minutes corresponds to the temperature a which steam distillation was expected. The value of removal rate constant (k) were calculated on dry and moisty silt soil, respectively, which showed linear with increasing microwave heating time. Therefore, addition of a certain amount of water to the contaminated soil can efficiently enhance the ability of the soil to absorb microwave energy and promote the evaporation of the volitile contaminants.

• Journal of Environmental Health Sciences
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• v.22 no.3
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• pp.116-122
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• 1996

This study has been focused on the applicability of microwave treatment of soil contaminated by volitile organic chemicals. Substrates studied were sand and sandy soil. These substrates were impregnated with toluene, tetrachloroethylene, o-xylene and p-dichlorobenzene. The microwave treatment was conducted in a modified domestic microwave oven: 2450 MHz, 700 W. The sandy soil temperature added water went up rapidly to about 130$\circ$C for 4 minutes. And then, the temperature appeared to plateau out. A series of tests were performed to depict the effectiveness of microwave treatment technique to organic contaminants from soils. Removal efficiencies in sandy soil and sand were increased with increasing water content and exposure time. Microwave radiation penetrates the soil and heats water throughout the matrix. Therefore, addition of a certain amount of water to the contaminated soil can efficiently enhance the ability of the soil to absorb microwave energy and promote the evaporation of the volitile contaminants. And the vapour pressure of impregnated organic contaminants becomes lower. the removal efficiency becomes poor.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.385-386
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• 2003

건축자재의 제작 및 도장공정, 합성수지 제조공정 등에서 많이 배출되는 휘발성 유기화합물(Volitile Organic Compounds, 이하 VOCs)은 이동성이 강하고 악취를 유발할 뿐만 아니라 마취성이 강하여 잠재적인 독성 및 발암성을 가진다. 이러한 VOCs의 제거방법 중 광촉매 제거법은 380 nm 이하의 자외선을 흡수하여 표면에서 생긴 전자와 정공으로 대부분의 유해물질을 제거하는 비교적 최근에 개발된 방법이다. 광촉매는 한번의 설치로 반영구적으로 사용할 수 있고 인체에 무해하며 유지비용이 적게 든다는 장점으로 인해 크게 부각되고 있다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.255-257
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• 1999

휘발성 유기화합물(VOCs)은 오존 및 광화학 스모그의 전구물질 내지는 원인물질로써, NOx나 햇빛 등과 반응하여 2차 오염물들을 생성한다. 특히, Benzene이나 Chloroform과 같은 VOCs 물질들을 강력한 발암성 물질로 규제되고 있다. 이러한 VOCs는 차량운행, 인쇄, 도장산업, 각종 석유정제과정 및 취급과 정등에서 많이 발생하며, 우리 시민들에게 호흡기 질환을 일으키거나 시계를 흐리게 한다. 따라서 휘발성 유기화합물에 의한 악영향과 교통 및 각종 산업시설에서의 발생원 확인 및 제거에 대한 관심이 매우 높다.(중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.04a
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• pp.225-226
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• 2002

1960년대 후반부터 경제발전이 가속화됨에 따라 석유를 기초로 한 유기화학 물질의 소모가 급속히 증가되어 휘발성 유기화합물질(VOCs : Volitile Organic Compounds)로 인한 대기오염이 날로 심각해져 가고 있다. VOCs가 대기 환경 및 인체에 미치는 영향을 몇몇 선진국에서 활발히 연구하고 있는 반면 국내에서는 VOCs에 관한 연구가 최근에 진행되고 있어 충분한 Data가 확보되지 못한 실정이다. 따라서 정확한 발생원을 파악하는 것이 매우 중요하며 많은 실험을 통하여 업종별 배출 농도를 파악하는 것이 중요하다. (중략)

• Proceedings of the Korean Information Science Society Conference
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• 2012.06a
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• pp.376-378
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• 2012

중앙 처리장치, 주기억장치, 보조기억장치로 이어지는 현재의 컴퓨터 구조에서 비휘발성 메모리 소자의 발전으로 주기억장치를 비휘발성 메모리 소자로 대체하는 컴퓨터 시스템의 변화가 요구되고 있다. 이런 흐름에 맞춰 주기억장치에 기반한 새로운 파일시스템을 제시한다. 또한 새롭게 제시된 파일시스템과 유사한 tmpfs를 이용하여 기존의 시스템에 쓰이던 ext4fs와 비교하여 성능의 향상을 확인한다.

• Journal of Environmental Science International
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• v.14 no.1
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• pp.53-60
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• 2005

The concentrations of volatile organic compounds(VOCs) in the ambient air were measured at various point(Source, source boundary) in Seongseo industrial complex during May to November 2003. Air samples were collected in Silcocan canister $(1{\ell},\;6{\ell})$ and analyzed using a cryogenic preconcentration system and GC/MSD. We identified 37 species by the US EPA(TO-14 method). The result showed a variety distribution of the con­centration, Higher concentrations of BTX, Styrene, 1,3,5-Trimethylbenzene, 1,2,4-Trimethylbenzene were observed at the sampling sites. They seemed to be emitted from the facility of wastewater treatment, reaction tank of chemistry factory and facility of Tenter. The concentrations of VOCs contents in Seongseo industrial complex were generally higher than those in Yeosu complex and Ulsan complex, although those were similar in Sihwa­Banwol complex.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.76.2-76.2
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• 2011

석탄의 탄종별 열분해 생성물은 석탄가스화기의 뮬레이션 기법의 첫 번째 단계이며 이러한 탄종별 생성물 예측은 가스화기의 성능, 즉 가스화기 출구 가스조성, 탄소전환율, 냉가스 전환율등을 예측하는데 있어 가장 기본적이고 중요한 절차이다. 본 논문에서는 석탄가스화기내 열분해 과정을 모사할 수 있도록 석탄 성상과 가스화기 운전압력에 따라 탄종별 고온고압 열분해시의 생성물을 정량적으로 계산하는 방법을 제시하였다. Merrick(1983)의 방법을 기반으로 석탄의 성상(공업/원소분석치), 가스화기 운전압력과 몇가지 상관관계식으로부터 고온고압하 열분해 생성물을 계산하는 방법이며 이를 프로그램화하여 가스화기 시뮬레이터용 모듈로 구성할 수 있도록 하였다. 또한, 국내 수입 5개 탄종에 대하여 열분해 생성물의 조성을 구하였으며 이를 상용 열분해모델의 결과와 서로 비교하였다. 열분해 생성물 조성의 분포는 다른 상용 프로그램 결과와 부합하였으며 생성물의 발열량도 원탄의 발열량과 적합한 결과를 보여주었다.

• Journal of ILASS-Korea
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• v.18 no.2
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• pp.106-111
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• 2013

Adulterations fuel have been using in the vehicle in these days. Because gasoline, diesel prices are rising every day. so people find more cheap price fuel. Adulterations fuel caused a serious air pollution problems. Adulteration fuel were made from waste engine oil, waste paint. According to Government regulations permit to be used recycle fuel(adulteration fuel) only in industrial boiler. Unburned fuel pollutants are effected to human health. In this paper, the hazardous air pollutants characteristics in the diesel vehicles according to adulterations of vehicle fuels were carried out in the NEDC test mode in chassis dynamometer. It is revealed that the all of the regulation pollutants (THC, NOx, CO and PM) emission in the adulterations of vehicle fuels was increased also the green house gas, $CO_2$ was increased. In the hazardous air pollutants characteristics, the VOCs(Volitile Organic Compounds) BTEX(Benzene, Toluene, Ethylbenzene, Xylene) emissions in the adulterations of vehicle fuels showed higher level than these in the diesel fuels.

• Journal of the Korean Society of Tobacco Science
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• v.10 no.2
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• pp.123-130
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• 1988

The volitile compounds Produced from the Maillard reaction of D-glucose and DL-alanine or DL-$\alpha$-aminobutyric acid using water or propylene glycol as a reaction amdeum were analysed by gas chromatofiraphy and mass spectrometry. From two kinds of reaction products in water 18 compounds were identified. The major compounds in a reaction product of glucose with alanine were 5-hydroxy methyl-2-furfural, 2-acetyl pyrrole and 2-formyl-5-methyl pyrrole, and those in a reaction product of glucose with $\alpha$-aminobutyric acid were 2-ethyl crotonaldehyde and 2-methyl-3, 5-dihydroxy-4H-pyran-4-one including the above 3 compounds. From two kinds of reaction products in propylene glycol solution, 35 compounds were identified. The major compounds in a reaction product of glucose with alanine were alkyl pyraainef, 2-methyl furfuryl alcohol and 2-acetyl pyrrole, and those in a reaction product of glucose with $\alpha$-aminobutyric acid were propionaldehyde PGA, 2-ehtyl crotonaldehyde, 2-acetyl pyrrole and 2-acetyl-5-ethyl furan.