• 한국미생물·생명공학회지
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• 제22권6호
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• pp.692-699
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• 1994

A bacterial strain which formed a distinct colony on agar plate containing phenol as a vapor phase and grew well in a liquid minimal medium was isolated and identified as Acinetobac- ter sp. GEM2. The optimal temperature and initial pH for the growth of Acinetobacter sp. GEM2 were 30$\circ$C and 7.0, respectively. Cell growth was inhibited by phenol at the concentration over 1500 ppm. Cell growth dramatically increased from 10 hours after cultivation and almost showed a stationary phase within 24 hours at which 95% of phenol was concomitantly degraded. Acinetobac- ter sp. GEM2 was capable of growing on aromatic compounds, such as benzoic acid, phenol, m- cresol, o-cresol, P-cresol, catechol, gentisic acid, and toluene, but did not grow on benzene, salicylic acid, p-toluic acid, and p-xylene. By the analysis of catechol dioxygenase, it seemed that catechol was degraded through both meta- and ortho-cleavage pathway. The growth-limiting log P value of Acinetobacter sp. GEM2 on organic solvents was 2.0.

• 한국대기환경학회지
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• 제22권3호
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• pp.325-336
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• 2006

The presence of volatile organic compounds (VOC), produced and released from both anthropogenic and natural sources, can accelerate the degradation of air quality in the surrounding area. In this study, we investigated the emission concentrations of VOC based on a total of 115 sample analysis made from 47 companies (representing 17 types of industry) at the Ban Wall industrial complex (Jun. 2004 to Jan. 2005). Through a statistical analysis of these measurement data, we inspected the emission characteristics of VOC in relation with industrial type and processing unit. When these data were compared each other, toluene was found to record the highest value of 423 ppb followed by ethylbenzene (68.3 ppb), m, p-xylene (43.6 ppb), o-xylene (27.2 ppb), styrene (23.9 ppb), and benzene (16.4 pub). In addition, by converting these VOC concentration data into malodor intensity, we attempted to account for their distribution patterns in terms of relative contribution to the malodor formation. The results of odor intensity conversion generally indicated that the odor intensities of individual VOC do not exceed the degree of 1. When our VOC results were compared against other odorous compounds measured concurrently, the results were highly contrasting each other. Despite relative insignificance as odorous compounds, these VOCs are generally found ubiquitously and in abundant quantities in this strong source area.

• Architectural research
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• 제7권1호
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• pp.19-26
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• 2005

Unlike other countries, Korea uses various kinds of wall-paper as finishing material. Conventional wall-paper consists of paper and vinyl, and petrochemical ink is used for the decoration of the surface. Adhesive is used to paste the wall with the wall-paper, which emit substantial amounts of VOCs and formaldehyde. In this study, VOCs characteristics emitted from specimens made of concrete, mortar, gypsum board and wall-paper were investigated using small chamber method. Moreover, concentration and emission factor of BTEX(Benzene, Toluene, Ethylbenzene, m,p,o-Xylene) and TVOC were investigated, and concentration and emission factor decay were estimated. As a result of the prediction, both time-dependent concentration decay and cumulative concentration can be converted into the logarithmic scale. Furthermore, prediction equations were developed from the experimental results under accurately controlled experimental conditions. Therefore, there may be difference if the estimated equations are directly applied to real buildings. Further research should be done on the generalization of the developed prediction equations.

• 한국대기환경학회지
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• 제17권3호
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• pp.233-240
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• 2001

The composition of volatile organic compounds (VOCs) was anlyzed for major emission sources such as vehicle exhaust, gasoline and diesel vapor, organic solvent vapor, and butane fuel gas. Low carbon-numbered hydrocarbons were found to be the dominant components of gasoline vehicle exhaust. In gasoline evaporative vapor, the predominant constituents were found to be butane and iso-pentane regardless of ambient air temperature. In case of diesel evaporative vapor was similar to those of gasoline evaporative vapor. The composition of organic solvent vapor from painting, ink and petroleum consisted mostly or aromatic compounds such as toluene and m, p, o-xylene. The hydrocarbon fraction of butane fuel gas. which is used by portable bunner, consisted mainly of propane (34%) and butane(70%).

• 한국환경보건학회지
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• 제33권4호
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• pp.242-249
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• 2007

Indoor air quality has become a topic of interest and concern. Especially changes in construction design and the increased use of synthetic products may result in an increasing of complaints and health effects about the quality of indoor air at home. In this study, nitrogen dioxide($NO_2$) and volatile organic compounds(VOCs) within new and established apartments on the basis of 4 years of building year were measured every 3 days consecutively during 60 days. We selected each 10 house in Seoul, Asan and Daegu, respectively, and produced risk numbers for hazard quotients, and predicted increases in incidence of cancer. The calculations were made for the adult with default exposure values and also made for a worst case scenario using Monte-Carlo simulation as describing the reasonable exposure(RME). Mean of Monte carlo analysis by benzene, in the construction under 4 years (male: $9.2{\times}10^{-5}$, female: $1.0{\times}10^{-4}$) and over 4 years (male: $6.8{\times}10^{-5}$, female: $8.3{\times}10^{-5}$) exceeded $10^{-6}$ of permitted standards in US EPA, RME of Monte carlo analysis. In construction under 4 yews (male: $9.9{\times}10^{-3}$, female: $9.6{\times}10^{-3}$) and over 4 years (male: $9.8{\times}10^{-3}$, female: $7.8{\times}10^{-3}$) exceeded $10^{-4}$ of maximum permitted standards in US EPA. The hazard index of non-carcinogenic pollutants by nitrogen dioxide, toluene, m,p-xylene and o-xylene, both male and female in apartment constructed under 4 yews and over 4 years was found less than the permitted standards of hazardous health effects in CTE. Significant cancer risks and non-cancer hazard quotients were predicted in under 4 yews of building year.

• 한국환경과학회지
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• 제30권3호
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• pp.219-234
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• 2021

Industrial emissions, mainly from industrial complexes, are important sources of ambient Volatile Organic Compounds (VOCs). Identification of the significant VOC sources from industrial complexes has practical significance for emission reduction. VOC samples were collected from July 2019 to June 2020. A Positive Matrix Factorization (PMF) receptor model was used to evaluate the VOC sources in the area. Four sources were identified by PMF analysis, including coating-1, coating-2, printing, and vehicle exhaust. The coating-1 source was revealed to have the highest contribution (41.5%), followed by coating-2 (23.9%), printing (23.1%), and vehicle exhaust (11.6%). The source showing the highest contribution was coating emissions, originating from the northwest to southwest of the sample site. It also relates to facilities that produce auto parts. The major components of VOC emissions from the coating facilities were toluene, m,p-xylene, ethylbenzene, o-xylene, and butyl acetate. Industrial emissions should be the top priority to meet the relevant control criteria, followed by vehicular emissions. This study provides a strategy for VOC source apportionment from an industrial complex, which is helpful in the development of targeted control strategies.

• 한국환경과학회지
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• 제32권6호
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• pp.403-417
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• 2023

In this study, we investigated the characteristics of Volatile Organic Compounds(VOCs) emission from painting and printing facilities in the Pyeongdong industrial complex in Gwangju. In addition, the objective was to understand the distribution characteristics of VOCs in the ambient air in industrial complexes affected by painting and printing facilities. The painting facility mainly emitted toluene, acetone, butyl acetate, 4-methyl-2-pentanone, ethyl acetate, 1-butanol, methyl ethyl ketone, m,p-xylene, o-xylene, 4-ethyltoluene, ethylbenzene, 3-ethyltoluene, and 1,2,4-trimethylbenzene. The main emission components in printing facilities were methyl ketone, ethyl acetate, acetone, 2-propanol, toluene, heptane, and butyl acetate. Ethyl acetate, toluene, 2-butanone, acetone, butyl acetate, 2-propanol, xylenes, and 4-methyl-2-pentanone were detected in the ambient air of the Pyeongdong industrial complex, consistent with the VOCs emitted by painting and printing facilities. The average concentration of seasonal TVOCs followed an order of winter > fall > spring > summer, whereas the concentrations of daytime and nighttime TVOCs were generally higher at night than those during the day, and the wind speed was greater during the day than it was at night. Based on a factor analysis of VOCs in the ambient air of Pyeongdong industrial complex, it is considered that organic solvents used in coating, printing, and electronics manufacturing facilities, as well as diesel vehicle emissions played a major role.

• 분석과학
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• 제26권4호
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• pp.287-297
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• 2013

본 연구는 고체 흡착관과 TD-GC/MS를 이용하여 7종의 휘발성 유기화합물에 대한 열탈착 분석조건을 최적화하였고, 기체상 및 액상 표준물질 첨가한 고체 흡착관을 사용하여 얻어진 검정곡선으로부터 휘발성 유기화합물을 비교 정량하였다. 대응표본 t-검정 결과, 스타일렌을 제외하고 벤젠, 톨루엔, 에틸벤젠, o-, m- 및 p-자일렌을 포함한 6종의 휘발성 유기화합물에 대해서는 액상 표준물질에 의한 표준 흡착관법이 기체상에 의해 제작된 표준 흡착관법이 유의수준 (${\alpha}=0.01$)에서 일치한 반면, 스타일렌에 대해서는 기체상 및 액체상으로 작성된 검정곡선에서 감응인자가 15.6% 차이가 발생하였는데 이것은 두방법 간에 유의한 차이가 있다는 것을 의미하였다. 따라서 BTEX를 포함한 스타일렌을 정량하는데 오차를 감소시키기 위해 액상 표준물질을 이용한 고체상 흡착관법을 사용하였다. 바로 그 점이 이 논문의 핵심내용임. 즉, 고가의 표준가스 대신에 저가의 액상 표준물질을 사용하여 정량하더라도 스타일렌 이외에 거의 동일한 값을 나타내기 때문임. 액체상 표준물법 조건에서 7종의 VOCs의 회수율은 $100{\pm}5%$, 재현성은 0.3~7.7%, 검출한계는 o-자일렌의 $0.01{\mu}g/m^3$에서부터 톨루엔의 $0.27{\mu}g/m^3$까지 범위를 나타내었다. 이러한 최적화된 분석방법을 신축 기숙사, 원룸 아파트 및 신차의 실내공기 중 휘발성 유기화합물을 정량하는데 적용하였다.

• 한국대기환경학회지
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• 제22권6호
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• pp.767-778
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• 2006

This study was carried out to evaluate the temporal variations of VOCs at an urban site, and to compare the concentrations of VOCs at an urban site in Daegu with those at a suburban site in Gyeongsan. Three hourly VOC samples in the ambient air were collected using a sequential tube sampler (STS 25, Perkin Elmer) throughout two weeks during May and July representing spring and summer seasons, respectively. The VOC concentrations were determined by an automatic thermal desorption apparatus with GC/MS analysis. A total of 12 VOCs of environmental concern were determined, which are chloroform, benzene, trichloroethylene, toluene, tetra-chloroethylene, ethylbenzene, m+p-xylenes, o-xylene, styrene, 1,3,5- and 1,2,4-trimethylbenzenes. Among 12 target VOCs, the most abundant compound appeared to be toluene, being followed by xylenes. The mean concentrations at the urbn site were 1.2 pub for benzene and 20.4 ppb for toluene (n=221) while the mean levels at the suburban site were 0.9 ppb and 4.3 ppb for benzene and toluene (n=96), respectively. The urban site concentrations were typically several-fold higher than those measured at the suburban site. It was found that general trends of VOC levels were significantly dependent on traffic conditions at the sampling site since VOC concentrations were at their maximum during rush hours, i.e. $9{\sim}12a.m$ and $6{\sim}9p.m$. Statistical investigations were conducted to investigate any significant relationships between VOC concentrations and affecting factors. Calculated correlation coefficients among VOCs were positively significant at a level of 0.05 in most cases. Increased concentrations of toluene in the urban site were estimated to reflect the effect of large industrial sources, mainly from textile industry.

• 한국물환경학회지
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• 제21권4호
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• pp.347-352
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• 2005

The isolated microorganisms, Pseudomonas stutzeri, Raoultella planticola (Klebsiella), Serratia fonticola from petroleum contaminated soil were enriched on benzene, toluene, ethylbenzene, o-xylene as carbon and energy sources, respectively. And the degradation characteristics of BTEX was observed in the mixed BTEX substrates. We found that the BTEX in mixed substrates were degraded more than 50% by three isolated microorganisms. Among three isolated microorganisms, the highest degradation rate was observed in Pseudomonas stutzeri, but the degradation rate was different according to microorganisms. In order to increase the degradation efficiency, we applied the co-culture of isolated three microorganisms. The mixture rate of pseudomonas stutzeri : Raoultella planticola (Klebsiella) : Serratia fonticola was follows ; 1:2:1, 1:1:2, and 2:1:1, respectively. In two co-culture of 1:2:1 and 1:1:2, degradation rate was lower than isolated microorganisms. However, degradation rate became higher than isolated microorganisms and the degradation rate of benzene, toluene, and ethylene was more than 95% in co-culture of 2:1:1. The degradation rate increased through the co-culture of isolated microorganisms, however, the growth rate decreased. This was resulted from the substrate competition between microorganisms. The co-culture of microorganisms is a effective method to increase the degradation efficiency of BTEX and the co-culture mixing rate is a important factor for determination of degradation efficiency.