• Asian Journal of Atmospheric Environment
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• 제8권4호
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• pp.192-201
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• 2014

A comprehensive profile of volatile organic compounds (VOCs) in public spaces is needed for interpreting indoor air measurements. Seasonal differences in profiles are critical for epidemiological study and risk assessment. The purposes of this study were to establish profiles for individual VOCs in 50 indoor public places in Korea and to determine seasonal variations in their concentrations. Air samples were taken during working hours. Seventy-two of the 91 targeted VOCs were identified using multiple standards. Six VOCs detected in all summer and winter samples were toluene, acetone, m,p-xylenes, ethylbenzene, benzene, and styrene. In summer, methyl ethyl ketone and 1-butanol were also found in all samples. In both seasons, the dominant indoor VOCs were toluene, m,p-xylenes, ethylbenzene, acetone, and isopropyl alcohol. Other chemicals associated with gasoline emissions were dominant in summer. Limonene was dominant only in winter due to the consumption of tangerines. The nine VOCs with the highest concentrations comprised 64.8% and 49.6% of the TVOC in summer and winter, respectively. Comparing two types of adsorbent tube, a single adsorbent tube with Tenax-TA had similar detection performance as a double adsorbent tube with Tenax and Carbotrap.

• Environmental Engineering Research
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• 제24권4호
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• pp.600-607
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• 2019

Volatile organic compounds (VOCs) are released from various sources and are unsafe for human health. Porous materials are promising candidates for the adsorption of VOCs owing to their increased ratio of surface area to volume. In this study, activated carbon (AC) impregnated cellulose acetate (CA) electrospun mats were synthesized using electrospinning for the removal of VOCs from the air mixture of ACs, and CA solution was electrospun at different proportions (5%, 10%, and 15%) in a single nozzle system. The different AC amounts in the electrospun mats were distributed within the AC fibers. The adsorption capacities were measured for acetone, benzene, and dichloromethane, using quartz crystal microbalance. The results elicited an increasing adsorption capacity trend as a function of the impregnation of ACs in the electrospun mats, while their capacities increased as a function of the AC concentration. Dichloromethane resulted in a faster adsorption process than acetone and benzene owing to its smaller molecular size. VOCs were desorbed with the N₂ gas purging, while VOCs were adsorbed at higher temperatures owing to the increased vapor pressures. The adsorption analysis using Dubinin-Astakhov equation showed that dichloromethane is more strongly adsorbed on mats.

• 대한건축학회논문집:구조계
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• 제34권12호
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• pp.57-63
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• 2018

The purpose of this study was to confirm the effects of flush-out on the reduction of Volatile Organic Compounds(VOCs) concentration in newly built residential buildings. The field measurements were conducted in two complexes of multi-residential buildings which are located suburban areas of Seoul. About three samples of residential buildings were selected in the field measurements. Two samples, B and C, had been flush-out with outdoor air more than seven days. The sample A was maintained at same condition during the flush-out because of the comparison. The indoor concentrations of VOCs in the three samples were measured at three times, before, during, and after flush-out. From the field measurements, it was confirmed that two samples' indoor VOCs' concentrations were considerably decreased after the flush-out comapred with those of the sample A in which the flush-out was not conducted. The decreases of indoor VOCs concentrations were corresponding to about 50% ~ 92% of the concentrations of before. Through the reviews for the previous studies, it was also found that the reduction effects of the flush-out is similar with the those of the bake-out which were reported in the previous studies.

• The Plant Pathology Journal
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• 제39권1호
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• pp.39-51
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• 2023

Common bean (Phaseolus vulgaris L.) is one of the most important crops in human food production. The occurrence of diseases, such as white mold, caused by Sclerotinia sclerotiorum can limit the production of this legume. The use of Trichoderma has become an important strategy in the suppression of this disease. The aim of the present study was to evaluate the effect of volatile organic compounds (VOCs) emitted by Trichoderma azevedoi CEN1241 in five different growth periods on the severity of white mold in common bean. The in vitro assays were carried out in double-plate and split-plate, and the in vivo assays, through the exposure of the mycelia of S. sclerotiorum to the VOCs of T. azevedoi CEN1241 and subsequent inoculation in bean plants. Chemical analysis by gas chromatography coupled to mass spectrometry detected 37 VOCs produced by T. azevedoi CEN1241, covering six major chemical classes. The profile of VOCs produced by T. azevedoi CEN1241 varied according to colony age and was shown to be related to the ability of the biocontrol agent to suppress S. sclerotiorum. T. azevedoi CEN1241 VOCs reduced the size of S. sclerotiorum lesions on bean fragments in vitro and reduced disease severity in a greenhouse. This study demonstrated in a more applied way that the mechanism of antibiosis through the production of volatile compounds exerted by Trichoderma can complement other mechanisms, such as parasitism and competition, thus contributing to a better efficiency in the control of white mold in bean plants.

• 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.

• 공기청정기술
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• 제24권2호
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• pp.42-47
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• 2011

• 기계와재료
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• 제10권3호통권37호
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• pp.78-86
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• 1998

• 한국안전학회지
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• 제28권2호
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• pp.37-41
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• 2013

In this work, we report the effect on the volatole organic compounds(VOCs) sensing properties of Copper phthalocyanine(CoPc) and Dilithium phthalocyanine(DiLiPc) thin films onto alumina substrates. Use evaporation method and the spin-coated method for sensing device. The materials of metallophthalocyanine macrocyclic compound solutions blended with N,N'-diphenyl-N,N'-bis(1-naphthyl)-1,1'-biphenyl-4,4"-diamine and/or Poly[2-methoxy-5-(2'-ethylhexyloxy)-1,4-phenylenevinylene] solutions. The influence of the blended in with metallophthalocyanine macrocyclic compounds on the resistance have been measured and analyzed in five different volatole organic compounds. The following results were obtained: The AFM 3D image of thin films deposited on metallophthalocyanine macrocyclic compound shows that the surfaces roughness were about CuPc 4.1~14.3 nm(7.5~8.1%), DiLiPc 10.3~22.2 nm(7.9~11.5%). The resistances decreases upon increasing the concentration of vapor organic compounds to CuPc and DiLiPc thin films. That thin films blended Copper phthalocyanine(CoPc) and Dilithium phthalocyanine(DiLiPc) with N,N'-diphenyl-N,N'-bis(1-naphthyl)-1,1'-biphenyl-4,4"-diamine and/or Poly[2-methoxy--5-(2'-ethylhexyloxy)-1,4-phenylenevinylene]. The resistances of blended thin films with N,N'-diphenyl-N,N'-bis(1-naphthyl)-1,1'-biphenyl-4,4"-diamine and/or Poly[2-methoxy--5-(2'-ethylhexyloxy)-1,4-phenylenevinylene] decreases upon increasing the concentration of volatole organic compounds(VOCs) on DiLiPc than CuPc compound thin films.

• Journal of Korean Society for Atmospheric Environment
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• 제17권E2호
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• pp.35-42
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• 2001

Recent development of photocatalytic degradation method that is mediated by TiO$_2$ is of interest in the treatment of volatile organic compounds(VOCs). In this study, trichloroethylene(TCE) and acetone were closely examined in a batch scale of photo-reactor as a function of water vapor, oxygen, and temperature. Water vapor inhibited the photocatalytic degradation of acetone, while there was an optimum concentration in TCE. A lower efficiency was found in nitrogen atmosphere than air, and the effect of oxygen on photocatalytic degradation of acetone was greater than on that of TCE. The optimum reaction temperature on photocatalytic degradation was about 45$^{\circ}C$ for both compounds. NO organic byproducts were detected for both compounds under the present experimental conditions. It was ascertained that the photocatalytic reaction in a batch scale of photo-reactor was very effective in removing VOCs such as TCE and acetone in the gaseous phase.

• 한국대기환경학회지
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• 제34권2호
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• pp.244-258
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• 2018

We performed this study to investigate the spatial, seasonal, and daily variations of the concentrations of volatile organic compounds (VOCs) in Pohang, where large steel industrial complexes are located. Ambient air sampling was undertaken at 4 sites during 4 seasons. Each sample was taken for 4 hours continuously for 8 consecutive days per season at each site. Three sites were located within the Pohang city, but one as a control site in Gyeongju. A total of 72 individual VOCs were determined by thermal desorption coupled with GC/MS, including aliphatics, aromatics, carbonyls and halides. The most abundant VOC was toluene, being followed by ethylbenzene and xylenes. Benzene concentrations(c.a. 0.7 ppb) were found to be much lower than the national ambient standard of 1.5 ppb. Overall, the VOCs levels in Pohang appeared to be lower than other national industrial complexes in Korea such as Shiwha-Banwol, Yeosu-Gwangyang, Gumi, and Ulsan. This implies that steel industry may not give significant impacts on the atmospheric levels of VOCs as much as petrochemical, electronic, and/or textile industries, where large amounts of organic solvents are used.