• 한국지하수토양환경학회지:지하수토양환경
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• 제17권3호
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• pp.76-85
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• 2012

Geochemical and ecological properties of remediated soil and gas exhausted from a low-temperature thermal desorption (LTTD) process were analyzed to assess the environmental impact of LTTD treatment. Soil characteristics were examined with regard to the chemical (EC, CEC, and organic matter) and the ecological (dehydrogenase activity, germination rate of Brassica juncea, and growth of Eisenia andrei) properties. The exhaust gases were analyzed based on the Air Quality Act in Korea as well as volatile organic compounds (VOCs) and mixed odor. Level of organic Organic matter of the soil treated by LTTD process was slightly decreased compared to that of the original soil because the heating temperature ($200^{\circ}C$) and retention time (less than 15 minutes) were neither high nor long enough for the oxidation of organic matter. The LTTD process results in reducing TPH of the contaminated soil from $5,133{\pm}508$ mg/kg to $272{\pm}107$ mg/kg while preserving soil properties. Analysis results of the exhaust gases from the LTTD process satisfied discharge standard of Air Quality Law in Korea. Concentration of VOCs including acetaldehyde, propionaldehyde, butyraldehyde and valeraldehyde in circulation gas volatilized from contaminated soil were effectively reduced in the regenerative thermal oxidizer and all satisfied the legal standards. Showing ecologically improved properties of contaminated soil after LTTD process and environmentally tolerable impact of the exhaust gas, LTTD treatment of TPH-contaminated soil is an environmentally acceptable technology.

• 공업화학
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• 제21권5호
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• pp.532-536
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• 2010

비스페놀A계 폴리카보네이트 내에 잔류하는 휘발성 유기화합물(VOCs)과 저분자량 화합물 함량 변화에 대한 연구가 케톤류(아세톤, 펜타논, 부타논)의 용매를 사용한 접촉추출 실험으로 수행되었다. 접촉추출 전 시료의 저분자량 화합물의 양은 2.6 wt%이었으나 아세톤으로 접촉추출 한 시료의 경우 0.96 wt%, 펜타논으로 접촉추출 한 시료의 경우는 1.53 wt%로 나타났고, 아세톤의 경우가 저분자량화합물 추출에 효율적임을 알 수 있었다. 휘발성 유기화합물 농도 변화 확인을 위해서 GC-Mass를 이용하였다. GC-Mass 실험 결과 휘발성 유기물로 염화메틸렌, 톨루엔 등이 확인되었고, 정량한 결과 펜타논의 경우가 아세톤의 경우보다 VOCs 처리에 효율적이었다. VOCs와 저분자량 화합물의 효율적 처리를 위해서는 아세톤과 펜타논의 혼합사용이 유리할 것으로 판단되고 혼합용매 사용결과 부피비로 50 : 50에서 최적의 결과를 나타내었다.

• 한국대기환경학회지
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• 제13권4호
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• pp.297-305
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• 1997

The experimental study by use of SPCP was fulfilled to remove toluene emitted from various industrial processes. First of all, discharge characteristic was experimented as the change of applied voltage and frequency. Then toluene removal characteristic was tested with the analysis of by-products. As a result, optimum electrical discharge condition was from 20.0 kHz to 25.0 kHz of frequency and from 3.5 kV to 4.0 kV of voltage range. The variation of applied voltage had a more important effect on the removal characteristic of toluene than the frequency variation. The toluene removal efficiency was proportioned to ozone concentration and retention time on discharge plate. It was dropped as increase of toluene concentration, but total treated volume of tolene per power consumption was high. The decomposed toluene was transformed to $CO, CO_2$ and particulates, and the rate of transformation to particulates was higher than CO and $CO_2$ at high toluene concentration. Particulates were increased from 0.017 $\mum$ to 0.3 $\mum$ range of size distribution.

• 한국분무공학회지
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• 제20권2호
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• pp.121-129
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• 2015

This study was designed to investigate the emission characteristics of unregulated pollutants (Aldehyde, VOCs, PAHs) as well as regulated pollutants (CO, HC, NOx and PM) from diesel medium-duty trucks. The emission characteristics of unregulated and regulated pollutants were assessed based on regulation standards (EURO 4 and EURO 5) and intake weight (2.5 ton and 5 ton). The results show that unregulated and regulated pollutants remained almost unchanged at higher speeds but decreased at below 23.5 km/h. Reduction in unregulated and regulated pollutants was noticeable in vehicles of recent regulation standards and light intake weight. The analysis of aldehyde using UPLC showed that formaldehyde and acetaldehyde of aldehyde were most dominant. The GC/MS analysis showed that benzene, toluene, ethylbenzene and xylene of VOCs was over 80% followed by toluene, xylene, ethylbenzene and benzene. In addition, the analysis of PAHs using GC/TOF-MS indicated that bi- and tricyclic aromatic ring of aromatic compounds was 73% and 53% at 2.5 ton and 5 ton vehicles, respectively. The results of this study will be contributed to establish HAPs inventory.

• 접착 및 계면
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• 제8권1호
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• pp.1-7
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• 2007

본 연구에서는 자동차 실내에서 발생되는 VOCs 성분 및 농도를 분석하기 위해 승용차와 RV차에 대해서 각각 15일, 30일, 45일, 60일 경과한 차량을 대상으로 시험하였다. 그 결과 TVOC는 승용차와 RV차 모두 기준치보다 2~8배 상회하였으며 승용차보다는 RV차량이 더 많이 검출되었다. 특히 톨루엔의 경우 30일 경과 후부터 급격히 감소되었으며 60일 경과 후에도 기준치보다 높게 검출되었다. 크실렌의 경우 45일 경과 후 기준치 이하로 검출됨을 확인하였다. 본 연구결과를 볼 때 자동차 내장부품의 무용제화 및 수성화 대체기술 개발이 시급함을 알 수 있었다. 아직 국제표준화 되어 있지 않은 VOCs의 시험방법표준화를 통하여 성분, 농도, 인체유해성을 충분히 분석하여 대체함으로써 친환경 자동차 생산에 기여할 수 있을 것으로 사료된다.

• 한국가스학회지
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• 제7권2호
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• pp.7-13
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• 2003

본 연구에서는 국내 휘발성 유기화합물질의 주요 취급시설에 대한 조사를 통하여 배출원별 배출메카니즘을 정립하고, 새로운 배출량산정모델을 제안하였다. 또한 각 배출원에 적용가능한 배출저감기술과 각 기술의 경제성 평가기법을 제안하였다. 여기에 배출원 DB, 화학물질물성치 DB, 기상정보 DB, 배출계수 DB 등의 정보를 연계하여 휘발성유기화합물질 배출량산정 및 관리 소프트웨어 VEER(VOCs Emission Estimation and Reduction)를 개발하였다. 결국 본 연구를 통해 개발된 VEER를 이용하여, 휘발성 유기화합물질 취급업체, 관리기관, 연구기관 등에서 쉽고 정확하게 배출원 인벤토리를 구축하고, 배출량을 산정하며, 계산된 결과를 바탕으로 각 배출원의 배출유량과 농도에 적합한 휘발성 유기화합물질 배출 저감기술을 선택하고, 여러 저감기술들에 대한 경제성을 평가함으로써, 저비용의 배출량 저감 및 배출원 관리기술을 선택하고, 설계할 수 있을 것으로 기대된다.

• 인간식물환경학회지
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• 제21권6호
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• pp.445-460
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• 2018

Exposure to indoor air pollution is an emerging world-wide problem, with growing evidence that it is a major cause of morbidity worldwide. Whilst most indoor air pollutants are of outdoor origin, these combine with a range of indoor sourced pollutants that may lead to high pollutant levels indoors. The pollutants of greatest concern are volatile organic compounds (VOCs) and particulate matter (PM), both of which are associated with a range of serious health problems. Whilst current buildings usually use ventilation with outdoor air to remove these pollutants, botanical systems are gaining recognition as an effective alternative. Whilst many years research has shown that traditional potted plants and their substrates are capable of removing VOCs effectively, they are inefficient at removing PM, and are limited in their pollutant removal rates by the need for pollutants to diffuse to the active pollutant removal components of these systems. Active botanical biofiltration, using green wall systems combined with mechanical fans to increase pollutant exposure to the plants and substrate, show greatly increased rates of pollutant removal for both VOCs, PM and also carbon dioxide ($CO_2$). A developing body of research indicates that these systems can outperform existing technologies for indoor air pollutant removal, although further research is required before their use will become widespread. Whilst it is known that plant species selection and substrate characteristics can affect the performance of active botanical systems, optimal characteristics are yet to be identified. Once this research has been completed, it is proposed that active botanical biofiltration will provide a cheap and low energy use alternative to mechanical ventilations systems for the maintenance of indoor environmental quality.

• 한국미생물·생명공학회지
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• 제50권2호
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• pp.202-210
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• 2022

Aflatoxin contamination in rice has been documented in a number of studies, and has a high incidence in Asian countries, and as such, there has been a growing interest in alternative biocontrol strategies to address this issue. In this study, 147 strains of yeasts and yeast-like fungi were screened for their potential to produce volatile organic compounds (VOCs) active against Aspergillus flavus strains that produce aflatoxin B₁ (AFB₁). Five strains within four different genera showed greater than 50% growth inhibition of some strains of A. flavus. These were Anthracocystis sp. DMKU-PAL124, Aureobasidium sp. DMKU-PAL120, Aureobasidium sp. DMKU-PAL144, Rhodotorula sp. DMKU-PAL99, and Solicococcus keelungensis DMKU-PAL84. VOCs produced by these microorganisms ranged from 4 to 14 compounds and included alcohols, alkenes, aromatics, esters and furans. The major VOCs produced by the closely related Aureobasidium strains were found to bedistinct. Moreover, 2-phenylethanol was the most abundant compound generated by Aureobasidium sp. DMKU-PAL120, while methyl benzeneacetate was the major compound emitted from Aureobasidium sp. DMKU-PAL144. On the other hand, 2-methyl-1-butanol and 3-methyl-1-butanol were significant compounds produced by the other three genera. These antagonists apparently inhibited A. flavus sporulation and mycelial development. Additionally, the reduction of the AFB1 in the fungal-contaminated rice grains was observed after co-incubation with these VOC-producing strains and ranged from 37.7 ± 8.3% to 60.3 ± 3.4%. Our findings suggest that these same microorganisms are promising biological control agents for use against aflatoxin-producing fungi in rice and other agricultural products.

• 한국환경과학회지
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• 제19권1호
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• pp.1-8
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• 2010

Only limited information is available on the measured exposure levels of residents according to the construction age of apartments. As such, present study was conducted to measure and to compare the bedroom, living-room, and outdoor air levels of MTBE and benzene, toluene, ethyl benzene and m,p-xylene(BTEX) in both newer and older apartments. For both newer and older apartments, all the compounds except for MTBE showed significantly higher levels in bedrooms or living-rooms as compared to the outdoor concentrations. The ratio of bedroom or living-room median concentration to outdoor concentration was close to 1 for MTBE, whereas it was larger than 1 for other target compounds. It was also found that the bedroom and living-room appeared to have similar indoor sources and sinks for BTEX, but not for MTBE. The median concentration ratios of the newer apartments to the older apartments ranged from 1.63 to 1.81, depending upon the compounds. In contrast, the MTBE concentrations did not differ significantly between the newer and older apartments, thereby suggesting that although newer buildings could emit more VOCs, this is not applicable to all VOCs. Conclusively, the findings of present study should be considered, when designing exposure studies associated with VOC emissions in buildings and/or managing indoor air quality according to construction age of buildings.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.613-618
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• 2011

More than 7 million persons use Seoul Metropolitan Subways (SMS) everyday and the number has been in increasing trend. With the increasing trend of concerns on indoor air quality(IAQ), the management of IAQ has become an important issue, especially in case of subway operators, because most of subway lines are placed underground with poor ventilation condition. The ultimate object of study develop independent cleaning device that reduce efficient fine particle and $CO_2$. Urban subway has characteristics about proper clean air flow, must be installed in narrow space and maintenance cycle has enough time. Two layered electrically pre-charged filters were used for removing particulate matters and gas absorbers are packed between two layer filters for removing gases pollutants such $CO_2$, VOCs and HCHO. Urban subway has characteristics about proper clean air flow, must be installed in narrow space and maintenance cycle has enough time. SCAP prototype is producted as all in one method which decrease fine dust, $CO_2$ and noxious gas. and basic test carry out with quantity of wind, a gap of pressure, sampling efficiency.