• 한국대기환경학회지
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• 제23권4호
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• pp.457-465
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• 2007

This study was performed to estimate the gas-particle partitioning of organochlorine pesticides (OCPs) in atmosphere, the samples were collected by PUF high volume air sampler for two years from June, 2000 to June, 2002. The gas phase fraction of ${\alpha/\gamma}-HCH$, heptachlor epoxide, ${\alpha/\gamma}-chlordane$ and trans-nonachlor was over 90%. But the gas phase fraction of ${\beta}-HCH$, p,p'-DDE, endosulfan sulfate, p,p'-DDD and p,p'-DDT was range of 20% through 80%, which means the gas phase fraction of OCPs components described above is sensitive to temperature. The correlation between the gas phase fraction and molecular weight of each OCPs component was not found in this research. The slope of regression line between gas-particle partitioning coefficient(${\log}K_p$) and subcooled liquid vapor(${\log}{P^o}_L$), gal-particle partitioning coefficient(${\log}K_p$) and octanol-air partitioning coefficient(${\log}K_{oa}$) which show -0.54 and 0.43 was not steep. So the equilibrium state between gas and particle was not reached and in this state the particulate fraction was low.

• 대한환경공학회지
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• 제27권12호
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• pp.1270-1276
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• 2005

대기 중 PAHs의 가스/입자 분배반응이 평형상태일 때 가스/입자분배계수($logK_p$)와 각 화합물의 증기압($logP_L^O$)과 선형식의 기울기가 -1이라는 것이 지금까지 알려진 사실이었다. 기러나 실제 대기에서 일어나는 가스/입자 분배와 차이를 보이는 현상에 대한 연구가 진행되면서 대기 입자의 불균일성 및 입자특성의 차이로 평형상태일 때 가스/입자 분배계수와 증기압과 기울기가 -1이 되지 않을 수도 있다는 주장이 제기되었다. 따라서 본 연구에서 이러한 가설을 토대로 대기 입자의 입경 크기에 따라 시료를 채취하여 평형상태일 때 입경의 크기에 따른 가스/입자 분배를 연구하였다. 대기 중 PAHs의 분배평형상태를 추정하기 위해 High-volume air sampler에서 채취된 입자와 가스를 이용하여 분배계수와 증기압을 구하고 이때 기울기가 -1에 가까운 시료를 평형상태에 있는 시료로 간주하였다. 그러나 평형상태에 해당하는 시료 중 같은 날 동시에 채취한 입경별 입자를 이용하여 각 입경 크기에 따라 분배계수와 증기압의 기울기를 계산한 결과에서는 평형상태일지라도 입경크기에 따라 동일한 기울기를 갖지 않고 입자가 커질수록 기울기가 완만해지는 현상을 나타내었다. 이러한 현상을 규명하기 위해 가스/입자 분배 반응의 두 가지 기작에 대하여 평형상태일 때 기울기가 -1이라는 결과를 도출하기 위해 가정했던 조건에 대하여 검토하였다. 그 결과 가스/입자 분배가 흡착이 주 반응이라 가정했을 때 입자의 크기에 따라 탈착엔탈피 변화량에 차이가 있었으며, 흡수인 경우에는 입자간의 활성계수의 차이를 간접적으로 확인할 수 있었다. 이는 평형상태일 경우에도 입자의 크기에 따라 가스/입자 분배평형에 이르는 정도가 다른 것으로 판단된다. 또한 가스/입자 분배반응 현상을 규명하기 위해서는 입자의 크기를 고려함으로써 그 현상을 좀 더 명확히 밝힐 수 있을 것으로 판단된다.

• 한국대기환경학회지
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• 제21권3호
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• pp.285-293
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• 2005

This study was aimed at estimation of gas-particle partitioning of polychlorinated biphenyls (PCBs) in ambient air. The samples were collected at urban site in Japan from March 2002 to January 2003. The concentration of total PCBs (from 4 CB to 10 CB) and TEQ (Toxic equivalent) ranged from 62 to $247\;pg/m^3$ and from 2 to $14\;fgTEQ/m^3 $, respectively. The average contribution $(\%)$ of gas phase to total PCBs concentration was above $80\%$, which suggests that in the atmosphere PCBs predominantly existed in the gas phase. The weak correlations between total PCBs concentration and temperature was found. However this result was due to a typhoon during summer and raining during sampling period. The gas-particle partition coefficient (Kp) was obtained as a function of temperature. The partition ratio of gaseous and particulate phase PCBs can be estimated for an arbitrary temperature. The plot of gas/particle partition coefficient (log Kp) vs. sub-cooled liquid vapor pressure $(log\;P_L)$ had reasonable correlations for individual samples but the slope varied among the samples (coefficients of determination for log Kp versus log $P_L$ plot were> 0.76 $(p<0.0001)$, except for 3 samples). As a result, the variations in the slope among the sampling period may be due to change of temperature, raining during sampling period and wind in this study.

• 한국환경과학회지
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• 제5권6호
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• pp.785-799
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• 1996

The incineration tests of mixed industrial wastes using the stoker type incinerator are carried out to investigate the partitioning characteristics of heavy metals during incineration. The results obtained from this study are as follow. The partitioning characteristics of heavy metals throughout this incinerator are found that, at given condition of $700^{\circ}C$, the elements with the relatively high boiling point such as Cr, Cu and Pb are partitioned into a bottom ash, a fry ash captured tv cyclone, and a flue gas stream, 67~88%, 2~19% and 6~16% of initial amount entering the incinerator, respectively, but the Cd and Hg of 75~81% is vaporized into the flue gas. It appears that the partitioning characteristics according to the particle size of ash is different between the bottom ash and the fly ash. For bottom ash, the fraction of partitioning into 75${\mu}{\textrm}{m}$ oversized particles is reatively high. For fly ash, the characteristics of distributions with the particle size can not be clearly shown.

• Asian Pacific Journal of Cancer Prevention
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• 제14권4호
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• pp.2461-2476
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• 2013

To assess environmental contamination with carcinogens, carbonaceous compounds, water-soluble ionic species and trace gaseous species were identified and quantified every three hours for three days st three different atmospheric layer at the heart of chiang-Mai, bangkok and hat-Yai from December 2006 to February 2007. A DRI model 2001 Themal/Optical Carbon Analyzer with the IMPROVE thermal/optical reflectance (TOR) protocol was used to quantify the organic carbon(OC) and elemental carbon content in $PM_{10}$. Diurnal and vertical variability was also carefully investigated. In general, OC and EC contenttration shoeed the highest values at the monitoring period o 21.00-00.00 as consequences of human activities at night bazaar coupled with reduction of mixing layer, decreased wind speed and termination of photolysis nighttime. Morning peaks of carboaceous compounds were observed during the sampling period of 06:00 -09:00, emphasizing the main contribution of traffic emission in the three cities. The estimation of incremental lifetime partculate matter exposure (ILPE) raises concern of high risk of carbonaceous accumulation over workers and residents living close to the observatory sites. The average values of incremental lifrtime particulate matter exposure (ILPE) of total carbon at Baiyoke Suit Hotel and Baiyoke Sky Hotel are approsimately ten time shigher then those air sample collected at prince of songkla University Hat-Yai campus corpse incinerator and fish-can maufacturing factory but only slightly higher than those of rice straw burnig in Songkla province. This indicates a high risk of developing lung cancer and other respiratory diseases across workers and residents living in high buildings located in Pratunam area. Using knowledge of carbonaceous fractions in $PM_{10}$, one can estimate the gas-particle partitioning of polycyclic aromatic hydrocarbons (PAHs). Dachs-Eisenreich model highlights the crucial role of adsorption in gas-particle partitioning of low molecular weight PAHs, whereas both absorption and adsorption tend to account for gas-particle partitioning of high molecular weight PAHs in urban residential zones of Thailand. Interestingly, the absorption mode alone plays a minor role in gas-partcle partitiining of PAHs in Chiang-Mai, Bangkok and hat-Yai.

• Environmental Engineering Research
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• 제11권1호
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• pp.33-44
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• 2006

The objective of this study was to develop and assess a method for estimating the rain scavenging ratios (RSRs) of particle-bound PAHs and PCBs using measured scavenging ratio of particulate matters (PM) and routinely available data of physico-chemical properties of PM. Paired atmospheric and rainwater sampling was conducted for a total of 4 rain events. Assuming equilibrium partitioning in rainwater-gas-PM system, an equation was derived for estimating the RSR of particle-bound chemicals as a function of RSR of PM and three equilibrium partition constants (i.e. dimensionless Henry's law constant, gas-particle partition coefficient, and water-particle partition coefficient). For all PAHs, the model significantly under-predicted the RSR while the model prediction for PCBs agreed with observation mostly within a factor of 5. The RSR model for the chemicals is of limited use as its accuracy critically depends on how close the observed partitioning of the chemicals in the gas-PM-rainwater system is to that estimated under the equilibrium assumption.

• Environmental Analysis Health and Toxicology
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• 제17권3호
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• pp.187-195
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• 2002

다환방향족탄화수소류 화합물의 증기상-입자상간의 분배평형의 설명을 위해 흔히 입자상의 흡착지점이 균질하고 총흡착면적은 TSP에 비례한다는 가정을 사용하는데 본 연구의 목적은 이러한 가정의 타당성을 평가하는 것이다. 본 연구를 위해 도심에서 6단의 다단계 대기중입자채집기를 사용하여 대기 중의 입자를 포집하였으며 이들 입자에 흡착된 phenanthrene, anthracene, fluoranthene, pyrene을 분석하여 입경별 분포를 측정하였다. 특히 연구기간 중에 황사현상이 일어나 입경분포나 입자의 기원이 매우 다른 경우에 대한 연구가 가능하였다. 주요연구결과로서 우선 야마사키가 제안한 분배평형의 온도 의존식은 제한된 범위에서 사용되어야 한다는 것이 관측되었다. 즉, 황사현상이 일어나는 경우와 같이 입자의 흡착특성과 입경분포가 보통때와 다른 경우에는 log Kp와 l/T의 관계에서 선형성이 상당히 저하되었다. 또한 특히 낮은 온도에서는 입자의 입경분포가 달라지면 전체적인 분배평형이 달라지게 되는 것으로 평가되었으며 입자의 흡착특성도 분배평형의 온도의존성에 결정적인 영향을 줄 수 있는 것으로 나타났다. 따라서 입자의 기원이 다양하거나 입경분포가 달라지면 흡착평형이 바뀌기 때문에 흡착특성의 균질성과 단순한 TSP를 전제로 하는 분배평형의 평가나 예측은 실제 대기조건에서는 정확하지 않을 수가 있으며 제한적인 조건에서 사용되어야 할 것이다.

• 한국대기환경학회지
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• 제22권4호
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• pp.499-508
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• 2006

Atmospheric concentrations of polycyclic aromatic hydrocarbons (PAHs) were measured at the Chonbuk National University located in Jeonju, four times between June and November 2002, each time for five days. Twenty-four compounds including five alkyl PAHs and byphenyl were analyzed. Average total concentration of 24 PAHs was 85 $\pm$ 15 ng/$m^3$ and about 94% of PAHs existed in the gas phase. On an average, naphthalene accounted for about 30% of the total PAHs concentration. The gas/particle partitioning was not much varied during the measurement period. High molecular weight PAHs with five and six rings were primarily associated with fine particles less than 1 $\mu$m. Lower molecular weight PAHs were evenly distributed in fine and coarse particles so that their distribution was similar to that of TSP.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2008년도 춘계학술대회 논문집
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• pp.469-470
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• 2008

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2009년도 추계학술대회 논문집
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• pp.309-310
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• 2009