• 한국환경과학회지
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• 제16권2호
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• pp.187-195
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• 2007

Long-term passive diffusive samplers(PDS) have been used to measure $NO_2\;and\;SO_2$ concentrations at 21 sampling sites in Daejeon, Korea during the period of January 2000 - December 2002. The spatial distributions of annual $NO_2\;and\;SO_2$ concentrations were mapped. Average annual $NO_2$ concentration over the sampling period was $28.5{\pm}12.5\;ppb$, ranging from 1.2 to 81.7 ppb. Average annual $SO_2$ concentration over the sampling period was $7.7{\pm}4.8\;ppb$, ranging from 0.6 to 26.8 ppb. On average, $NO_2$ concentration was approximately 5.8%(1.6 ppb) larger in 2002. $SO_2$ concentration was decreased by 13%(1.1 ppb) during the sampling period. The seasonal variation of $NO_2\;and\;SO_2$ concentration was observed with a tendency to be higher in fall and winter. $NO_2\;and\;SO_2$, concentrations measured at different site types(patterns of land use) show significant difference. The observed difference in concentration was associated with difference in emissions of $NO_2$ from motor vehicles and $SO_2$ by non-traffic fuel consumption for heating.

• KSBB Journal
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• 제15권4호
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• pp.388-392
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• 2000

한지자숙폐액을 이용한 Saccharomyces cerevisiae의 배양에 서 glucose의 자동분석 및 첨가에 의해 균농도를 증가시킴으로써 폐액의 재이용성을 향상시키파 하였다 배양액의 glucose를 자동분석하고 자동첨가하기 위하여 ceramic sampler, sampling, ralve, injection valve, glucose oxidase column, debubbler, flow cell과 백금전극, potentiostat, computer와 interface card, 및 tubing pump블로 구성된 glucose 자동분석 및 첨가시스템을 제작하였으며, glucose의 자동분석에는 glucose oxidase를 이용한 on-line FIA법을 채택하였다. 효모의 배양중 glucose자 동분석 및 첨가시스템을 사용하여 glucose를 자동첨가한 결과 배양액의 포도당농도가 $176{\pm}31 mg/L$ 의 낮은 농도로 제어 되었으며, glucose와 $>(NH_4)_2S0_4$의 첨가에 의해 총균수가 3.1 배 증가하였다.

• 한국대기환경학회지
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• 제20권1호
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• pp.17-31
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• 2004

The subway play an important part in serious traffic problems. However, because subway system is a closed environment, many serious air pollution problems occurred in subway stations and injured passenger's health. Therefor, it is a necessary to identify sources and to estimate pollutant sources in order to protect passenger's health and to keep clean subway environment. The purpose of this study was to analyze a air quality in the subway stations and to apply a new receptor methodology for quantitatively estimate of PM10 sources. In this study, the size distributions of particulate matters has been measured by using Aerosizer LD (U.S.A., API, Inc.). It's real time measurement capability of time-of-flight technique offers a significant advantage of user convenience and air pollution management. Also, the mass concentrations of PM 10 has been measured by using mini-vol portable sampler (U.S.A., Airmetrics Co.). The sampling performed in Seoul subway stations during the period of February 2000 and April 2000. The number distribution data used in this study consisted of 26 raw data sets in the Jongno-sam-ga station. Correlation Analysis can be used in subway stations for source separation and identification. Then, number contribution from each source is determined by the particle number balance (PNB). The mass concentration data used in this study consisted of 31 raw data in the 8 different stations. The mass contributions of PM10 sources in the concourse by using PMF/CMB model.

• 한국대기환경학회지
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• 제15권4호
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• pp.495-503
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• 1999

Airborne particulate matter $(PM_{10})$ collected using high volume air sampler and silica fiber filter were analyzed by Instrumental Neutron Activation Analysis(INAA), Inductively Coupled Plasma Atomic Emission Spectrometry(ICP-AES) and Atomic Absorption Spectrometry(AAS), and the results were compared with each other. 30~40 trace elements in environmental standard reference materials(NIST SRM 1648 and NIES CRM No.8) were analyzed for the analytical quality control. The relative error for two-third of elements detected was less than 10%, and the standard deviation was less than 15%. During the sampling period for 24 hours, the mass concentration of total suspended particulate was 36.1$\mu\textrm{g}$/㎥ and the value is lower than the critical level in Korea. In the results of NAA, the elements of Al, As, Ba, Fe, La, Mg, Na, Sb, Zn were well agreed with those of other methods. In statistical estimation between different methods, the deviation of Al, Ba, Cr, Fe was less than 10% and quite reliable.

• 한국환경보건학회지
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• 제24권3호
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• pp.114-123
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• 1998

Particulate matters(less than 10 $\mu$m, PM10) at Kanghwa and Yangyang, which are located in the western and the eastern coastal regions in Korea, were measured in using low volume air sampler from December 1995 to November 1996, and their characteristics were investigated from the view point of background level.(and in order to characterize the particulate matters.) The particulate matters were analyzed for major water soluble ionic components(SO$_{4}^{2-}$, NO$_{3}^{-}$, Cl$^{-}$, Na$^{+}$, NH$_{4}^{+}$, K$^{+}$, Mg$^{2+}$ and Ca$^{2+}$) by ion chromatography. Mass concentrations of particulate matters were $48.77 \pm 22.45 \mug/m^{3}$ at Kanghwa and $54.04 \pm 32.98 \mug/m^{3}$ at Yangyang and SO$_{4}^{2-}$, NO$_{3}^{-}$ and NH$_{4}^{+}$ contributed largely to water soluble ionic components. nss(non sea salt)-SO$_{4}^{2-}$, contributed more than 95 percentage to SO$_{4}^{2-}$ and nss-K$^{+}$ and nss-Ca$^{2+}$ also contributed high percentages to K$^{+}$ and Ca$^{2+}$. It was supposed that most SO$_{4}^{2-}$, was originated from anthropogenic sources, and K$^{+}$ and Ca$^{+}$ were mainty originated from soil. The results of factor analysis suggested possibility of interpreting the correlation between air pollutants and regional characteristics.

• 한국대기환경학회지
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• 제18권4호
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• pp.297-303
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• 2002

Fine particles (d$_{p}$ < 2.5 $\mu$m) were measured using an annular denuder system (ADS) in Chongju. The data set was collected on fifty-eight different days with a 24-hr sampling period from October 27, 1995 through August 25, 1996. Particulate nitrate in the ADS was also measured on teflon and nylon filters in series behind denuders to collect HNO$_3$, HNO$_2$, SO$_2$and NH$_3$. From this study. the mean concentration of particulate nitrate of PM$_{2.5}$ in the ADS were seen with the following order: winter (5.05) ＞fall (4.36) ＞spring (3.92) > summer (1.10 $\mu\textrm{g}$/㎥). Nitrate losses, which calculated from the ratio of nylon filter nitrate to the sum of teflon and nylon filter nitrates, varied in the following manner summer (72.2%) > spring (42.6%) > fall (23.5%)> winter (0.4%). Especially, gaseous nitric acid was dominant at temperature higher than 8$^{\circ}C$ while particulate nitrate was major species in total nitrate below that temperature. This indicates the particulate nitrate loss is strongly correlated rather with ambient temperature.e.e.

• 한국대기환경학회지
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• 제12권3호
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• pp.341-350
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• 1996

We determined 6 polycyclic aromatic hydrocarbons (PAHs) fluranthene, pyrene, benz(a)anthracene, chrysene, benzo(a)pyrene, dibenzo(a,h)anthracene). A total of 129 samples has been collected from September 1990 to September 1994 on 2 different types of filters (quartz fiber filter, glass fiber filter) by a PM-10 high volume air sampler at the Kyung Hee University-Suwon campus. The organic components in the PM-10 were extracted by an ultrasonication process with benzene:ethanol(4:1, v/v) prior to the analysis by using a GC/FID. We had also investigated the decaying quantity of 6PAHs at the room temperature. For example, chrysene was decayed by 56.7% after 4 days and benzo(a)anthracene by 84.2% after 30 days. All of PAHs were almost completely decayed after a year. We extensively estimated the decay rates by regression analyses for existing 18 raw data sets. Based on the decay rate constants $(\beta)$, pyrene was rapidly decayed by 19.0 $\times 10^{-2}$/day; on the other hand, dibenzo(a,h)anthracene slowly by 0.7 $\times 10^{-2}$/day. Applying the decay rates of PAHs on stored and dated samples, we could reasonably determine annual and seasonal concentration average of PAHs in particulate matters smaller than 10 $\mu$m.

• Nuclear Engineering and Technology
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• 제36권5호
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• pp.450-459
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• 2004

For the evaluation of emission sources by air sampling, airborne particulate matter for fine (<2.5 ${\mu}m2$ EAD : $PM_{2.5}$) and coarse partical (2.5-10 ${\mu}m2$ EAD : $PM_{2.5-10}$ fractions were collected using a Gent stacked filter unit low volume sampler and two types of polycarbonate filters. Air samples were collected twice monthly at two regions in and around Daejeon city in the Republic of Korea from January to December 2002. Monthly mass concentration of $PM_{2.5}$ and $PM_{2.5-10}$ were measured and the concentrations of 10 marker elements (Al, Sc, Ti ; Na, Cl ; As, V. Sb, Br, Se) were determined by an instrumental neutron activation analysis. Analytical quality control was corried out using certified reference materials. Enrichment factors were also calculated from the monitoring data to classify the anthropogenic and crustal origins.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2006년도 추계학술대회 논문집
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• pp.152-157
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• 2006

The air pollutant emission from the railroad diesel locomotive is still a significant environmental concern in many countries including Korea and Unites States. The emission characteristics of the railroad diesel locomotive were extensively studied in this study. Particulate matter (PM) and nitrogen oxides ($NO_x$) emitted from a large locomotive engine (2-cycle, 16-cylinder, and 3,000-horsepower) under various engine-rating conditions was analyzed with a scanning mobility particle sizer and a gas stack sampler by using a dilution tunnel. We could gain the emission values of 2.1 g/horsepower-hour for PM and 42.7 g/horsepower-hour for $NO_x$. We proposed the emission reduction goal of the railroad diesel locomotive for Korea in comparison with the regulation of United States.

• 환경위생공학
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• 제16권4호
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• pp.21-30
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• 2001

Vehicles, especially diesel-using, are a major source of airborne particulate matter(PM), nitrogen dioxide($NO_2$) and so on in metropolitan cities such as Seoul. Therefore workers, who are mainly merchants, near roadside may be highly exposed to air pollutants from exhausted emissions of vehicles. This means that occupational type and location can affect the workers＇health by exposure to outdoor pollutions of ambient as well as indoor pollutions of working condition, respectively. In this study, we simultaneously measured the PM3.5 and $NO_2$concentrations in indoor and outdoor of shoes repair shops in Seoul, which were generally located at roadside in Korea. Shoes repairmen were highly exposed to PM3.5 and $NO_2$ both indoor and outdoor of repair shops comparing with other sub-population groups. High exposure to air pollutants for shoes repairmen was considered to be outdoor source from exhausted emission of vehicles and indoor source from working condition. The $PM3.5/NO_2$ concentration ratio was $1.17{\pm}$0.59 in roadside, of which ratio was higher 7han ratios of other studies. This result suggested that major air pollutant in Seoul was fine particle. Also, this PM3.5 to $NO_2$ ratio will be used in environmental exposure and risk assessment by estimation of PM3.5 concentration as measuring the only $NO_2$ concentration with small and accurate $NO_2$ passive sampler.