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흡착-열탈착 가스크로마토그래피 질량분석 방법을 이용한 숲속 대기 중 자연적 휘발성 유기화합물 분석에 관한연구
이효정,이경민,김현영,최성민,박범진 한국환경분석학회 2022 환경분석과 독성보건 Vol.25 No.4
Phytoncide, a forest healing indicator, is known to help suppress depression, anxiety, and stress of human. Furthermore, it has positive effects on blood pressures, pulses, and mood fluctuations. Previous studies mostly focused on phytoncide emission trends and its concentration prediction in forest. Moreover, a direct comparison of phytoncide concentrations between existing studies is often challenging owing to the use of differingunits, target analytes, analysis conditions, as well as unreported concentrations per type of the compound. Therefore, this study evaluated the overall performance of adsorption sampling and thermal desorption coupled with gas chromatography to evaluatethe phytoncide concentration in a forest atmosphere. To this end, the analysis quality management and analysis accuracy were evaluated for on-site samples in two different laboratories. The phytoncide analysis results obtained from each laboratory can serve as reference data for the adsorption capture-thermal desorption method applied to biogenic volatile organic compounds.
Ahn, J.H.,Kim, K.H.,Szulejko, J.E.,Kwon, E.E.,Deep, A. Academic Press ; Elsevier Science Ltd 2016 Microchemical journal Vol.125 No.-
In this research, we investigated the breakthrough volume (BTV) and temporal performance of two types of sorbent tube (ST) sorbent beds toward 10 (target) biogenic volatile organic compounds (BVOCs) ((1) isoprene, (2) (+)-α-pinene, (3) camphene, (4) (+)-β-pinene, (5) (+)-3-carene, (6) α-phellandrene, (7) α-terpinene, (8) ®-(+)-limonene, (9) γ-terpinene, and (10) p-cymene) and two (reference) anthropogenic volatile organic compounds (AVOCs) ((11) benzene and (12) toluene). The analysis of their vaporized liquid-phase working standards was carried out using thermal desorption-gas chromatography-mass spectrometry (TD-GC/MS). To this end, the performance of two ST types (CC (Carbopack C) and CBX (Carbopack C, Carbopack B, and Carbopack X)) was tested as a function of a few key variables, e.g., sorbent type, N<SUB>2</SUB> gas purge volume, and sampling temperature. The CBX ST gave recoveries of 100+/-10% at 60<SUP>o</SUP>C for two BVOCs (camphene and α-terpinene). However, three compounds (isoprene, (+)-α-pinene, and (+)-β-pinene) showed poor recoveries (0.7, 59.3, and 11.3%, respectively), whilst p-cymene recorded an excess recovery (~190%). In contrast, for the CC ST, BT for (+)-α-pinene and camphene increased with purge volume, while isoprene was not detected. Accordingly, the range of BTV<SUB>5%</SUB> and BTV<SUB>50%</SUB> values (L/g) for each compound with CC ST were 1.7 (toluene)-17 (camphene) and 15 (toluene)-570 ((+)-α-pinene), respectively. In summary, a three-bed CBX with the higher BTV is the preferred choice for environmental sampling for a wide range of BVOCs compared to a one-bed CC ST. The recovery of CBX ST for 10 out of 12 analytes (after >150 reconditioning/loading/TD cycles) remained constant in terms of response factor, while the response factors of isoprene and β-pinene were highly variable. Both the present work and the reported literature recoveries showed similar and divergent results which are discussed in terms of high temperature on-sorbent reactions.
The storage stability of biogenic volatile organic compounds (BVOCs) in polyester aluminum bags
Ahn, J.H.,Deep, A.,Kim, K.H. Pergamon Press ; Elsevier [distribution] 2016 Atmospheric environment Vol.141 No.-
<P>In this study, the sorptive loss properties of biogenic volatile organic compounds (BVOCs) in polyester aluminum bags were investigated as a function of storage duration. To this end, the relative recovery of gas phase standards of BVOCs, obtained via vaporization of liquid phase standards, was computed by calibrating their standards (response factors: RF) represnting each phase. Accordingly, the results indicated either slight loss (-5.59% (isoprene), -2.39% (camphene), -1.69% ((R)-(+)-limonene), -0.88% (p-cymene)) or gain (1.47% (gamma-terpinene), 2.27% (alpha-terpinene), 2.63% (alpha-phellandrene), 2.73% ((+)-3-carene), 3.93% ((+)-beta-pinene), and 5.98% ((+)-alpha-pinene)). Through comparison of the calibration results across storage time, the temporal stability of BVOCs was assessed. Longer BVOC storage time in polyester aluminum (PEA) bags lowered the relative recovery of BVOCs. The relative loss of BVOCs, if calculated in terms of mean bag standard RF ratios (relative to liquid standard) across elapsed time, decreased systematically: 0.99 +/- 0.05 (0 h), 0.88 +/- 0.06 (24 h), 0.66 +/- 0.11 (72 h), and 0.62 +/- 0.14 (120 h). It is thus recommended to complete the analysis of BVOC in PEA bags within 24 h of sample acquisition. As such, it is important to apply appropriate sampling approaches with a proper storage plan when measuring ambient BVOCs collected by bag sampling methods. (C) 2016 Elsevier Ltd. All rights reserved.</P>
A modeling study of the impact of natural and urban forest on ambient ozone
선우영,Kwang Jin Kim,김유정,Young-Il Ma,김조천 한국화학공학회 2008 Korean Journal of Chemical Engineering Vol.25 No.3
Impact estimation of biogenic VOCs (Volatile Organic Compounds) to control ambient ozone is needed. For this, BVOCs emission is calculated by using BEIS, and the impact of ozone is estimated with UAM in the research area, Daegu metropolitan city. It is estimated that 59 ppb and 50 ppb of ozone concentration is caused by BVOCs emissions and anthropogenic emissions, respectively. As for tree type, deciduous trees have greater influence than conifers on the daily maximum 1-hr ozone concentration though the former’s distribution area is smaller than the latter’s. In addition, variation of ozone concentration by BVOCs emission is more sensitive in city areas compared to rural areas. If we change the landscape from woody plants (urban trees) to lower ozone-forming potential (OFP) species, it should lead to a reduction in grids that exceed the national ambient ozone standard.
Sou N. Matsunaga,Kojiro Shimada,Tatsuhiko Masuda,Junya Hoshi,Sumito Sato,Hiroki Nagashima,Hiroyuki Ueno 한국대기환경학회 2017 Asian Journal of Atmospheric Environment (AJAE) Vol.11 No.1
Ozone concentration in Tokyo Metropolitan area is one of the most serious issues of the local air quality. Tropospheric ozone is formed by radical reaction including volatile organic compound (VOC) and nitrogen oxides (NOx). Reduction of the emission of reactive VOC is a key to reducing ozone concentrations. VOC is emitted from anthropogenic sources and also from vegetation (biogenic VOC or BVOC). BVOC also forms ozone through NOx and radical reactions. Especially, in urban area, the BVOC is emitted into the atmosphere with high NOx concentration. Therefore, trees bordering streets and green spaces in urban area may contribute to tropospheric ozone. On the other hand, not all trees emit BVOC which will produce ozone locally. In this study, BVOC emissions have been investigated (terpenoids: isoprene, monoterpenes, sesquiterpenes) for 29 tree species. Eleven in the 29 species were tree species that did not emit BVOCs. Three in 12 cultivars for future planting (25 %) were found to emit no terpenoid BVOCs. Eight in 17 commonly planted trees (47%) were found to emit no terpenoid BVOC. Lower-emitting species have many advantages for urban planting. Therefore, further investigation is required to find the species which do not emit terpenoid BVOC. Emission of reactive BVOC should be added into guideline for the urban planting to prevent the creation of sources of ozone. It is desirable that species with no reactive BVOC emission are planted along urban streets and green areas in urban areas, such as Tokyo.
Iqbal, M.A.,Kim, K.H. Elsevier 2014 Journal of chromatography Vol.1373 No.-
In the analysis of biogenic volatile organic compounds (BVOCs) in ambient air, preparation of a sub-ppb level standard is an important factor. This task is very challenging as most BVOCs (e.g., monoterpenes) are highly volatile and reactive in nature. As a means to produce sub-ppb gaseous standards for BVOCs, we investigated the dynamic headspace (HS) extraction technique through which their vapors are generated from a liquid standard (mixture of 10 BVOCs: (1) α-pinene, (2) β-pinene, (3) 3-carene, (4) myrcene, (5) α-phellandrene, (6) α-terpinene, (7) R-limonene, (8) γ-terpinene, (9) p-cymene, and (10) Camphene) spiked into a chamber-style impinger. The quantification of BVOCs was made by collection on multiple-bed sorbent tubes (STs) and subsequent analysis by thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS). Using this approach, sub-ppb level mixtures of gaseous BVOCs were generated at different sweep cycles. The mean concentrations of 10 BVOCs generated from the most stable conditions (i.e., in the third sweep cycle) varied in the range of 0.37+/-0.05 to 7.27+/-0.86ppb depending on the initial concentration of liquid standard spiked into the system. The reproducibility of the gaseous BVOCs generated as mixture standards, if expressed in terms of relative standard error using the concentration datasets acquired under stable conditions, ranged from 1.64 (α-phellandrene) to 9.67% (R-limonene).
김형진,Kumiko Takata,Katsunori Tanaka,Ryoji Yamashima,Jun Matsumoto,Kazuyuki Saito,Toshihiko Takemura,Tetsuzo Yasunari 한국기상학회 2014 Asia-Pacific Journal of Atmospheric Sciences Vol.50 No.4
A series of 60-year numerical experiments starting from 1851 was conducted using a global climate model coupled with an aerosol-cloud-radiation model to investigate the response of the Asian summer monsoon to variations in the secondary organic aerosol (SOA) flux induced by two different estimations of biogenic volatile organic compound (BVOC) emissions. One estimation was obtained from a pre-existing archive and the other was generated by a next-generation model (the Model of Emissions of Gases and Aerosols from Nature, MEGAN). The use of MEGAN resulted in an overall increase of the SOA production through a higher rate of gasto- particle conversion of BVOCs. Consequently, the atmospheric loading of organic carbon (OC) increased due to the contribution of SOA to OC aerosol. The increase of atmospheric OC aerosols was prominent in particular in the Indian subcontinent and Indochina Peninsula (IP) during the pre- and early-monsoon periods because the terrestrial biosphere is the major source of BVOC emissions and the atmospheric aerosol concentration diminishes rapidly with the arrival of monsoon rainfall. As the number of atmospheric OC particles increased, the number concentrations of cloud droplets increased, but their size decreased. These changes represent a combination of aerosol-cloud interactions that were favorable to rainfall suppression. However, the modeled precipitation was slightly enhanced in May over the oceans that surround the Indian subcontinent and IP. Further analysis revealed that a compensating updraft in the surrounding oceans was induced by the thermally-driven downdraft in the IP, which was a result of surface cooling associated with direct OC aerosol radiative forcing, and was able to surpass the aerosolcloud interactions. The co-existence of oceanic ascending motion with the maximum convective available potential energy was also found to be crucial for rainfall formation. Although the model produced statistically significant rainfall changes with locally organized patterns, the suggested pathways should be considered guardedly because in the simulation results, 1) the BVOC-induced aerosol direct effect was marginal; 2) cloud-aerosol interactions were modeldependent; and 3) Asian summer monsoons were biased to a nonnegligible extent.