• 한국대기환경학회지
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• 제32권1호
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• pp.67-81
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• 2016

In order to examine the variation characteristics of chemical compositions in accordance with the different meteorological conditions, $PM_{10}$ and $PM_{2.5}$ were collected at Gosan site of Jeju Island in 2014, and then their ionic and elemental species were analyzed. The concentrations of nss-$SO{_4}^{2-}$ and $NH_4{^+}$ were respectively 4.3 and 3.3 times higher in fine particle mode ($PM_{2.5}$) compared to coarse particle mode ($PM_{10-2.5}$), however $NO_3{^-}$ concentration was 1.6 times higher in coarse mode compared to fine particle mode. During Asian dust days, the concentrations of nss-$Ca^{2+}$ and $NO_3{^-}$ increased highly as 7.7 and 4.5 times in coarse particle mode, and 3.0 and 4.9 times higher in fine particles, respectively. Especially, the concentrations of the crustal species (Al, Fe, Ca, K, Mn, Ba, Sr, etc.) indicated a noticeable increase during the Asian dust days. For the haze days, the concentrations of secondary pollutants increased 2.2~2.7 and 2.9~6.0 times in coarse and fine particles, respectively, and they were 0.8~1.1 and 1.8~2.4 times, respectively, during the mist days. The aerosols were acidified largely by sulfuric and nitric acids, and neutralized mainly by ammonia in fine particle mode during the haze days, but neutralized by calcium carbonate in coarse particle mode during the Asian dust days. The clustered back trajectory analysis showed that the concentrations of nss-$SO{_4}^{2-}$, $NO_3{^-}$, and $NH_4{^+}$ were relatively high when the inflow pathway of air mass was from the southern part of China.

• Asian Journal of Atmospheric Environment
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• 제6권4호
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• pp.281-287
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• 2012

Aerosol concentrations at the CC-Lag site in the Teshio Experimental Forest increased from winter to spring and sometimes showed extremely high values associated with Kosa and/or forest-fire events. The range and mean of the mass concentrations of aerosol chemical species were as follows: total particulate mass, 1.2-29, 5.0; elemental carbon, 0.061-2.2, 0.43; organic carbon, 0.059-3.5, 0.79; and sulfate, 0.12-6.2, 1.8 ${\mu}g/m^3$. The total masses of the deposited particles on hybrid larch and on bamboo leaves were approximately 35 and 30 ${\mu}g/cm^2$, respectively. The amounts of soil particles on the leaves were 6 ${\mu}g/cm^2$ for the upper part of hybrid larch, 2 ${\mu}g/cm^2$ for the lower part of hybrid larch, and 1 ${\mu}g/cm^2$ for Sasa bamboo leaves. The amounts of deposited black carbon were 2.3 ${\mu}g/cm^2$ for the upper part of hybrid larch, 0.6 ${\mu}g/cm^2$ for the lower part of hybrid larch, and 0.2 ${\mu}g/cm^2$ for Sasa bamboo leaves. Half of the total deposited particular mass was attached on the hybrid larch; however, most of the total deposited mass was adhered on the Sasa bamboo leaves. Regardless of the species, there tend to be more deposited particles on the leaves in the upper part than in the lower part, with only a few meters height difference. Comparing the composition of the deposited particles to that of the atmospheric aerosols without any size cut, the fractions of water-soluble material sulfate and sea salt in the deposited aerosols were about one tenth and one hundredth lower than that in the aerosols, respectively. On the basis of the measured concentration and the deposited amount on leaves, the deposition velocity of black carbon was estimated to be approximately 0.5 cm/s.

• 한국대기환경학회지
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• 제23권6호
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• pp.675-688
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• 2007

To characterize organic and elemental carbon (OC and EC), and water-soluble organic carbon (WSOC) contents, daily $PM_{2.5}$ measurements were performed in August 2006 (summer) and Jan $11{\sim}Feb$ 12 2007 (winter) at an urban site of Gwangju. Daily size-segregated aerosol samples were also collected for WSOC analysis. No clear seasonal variations in EC and WSOC concentrations were observed, while seasonal differences in OC concentration, and OC/EC and WSOC/EC ratios were shown. The WSOC/OC ratio showed higher value in summer (0.56) than in winter (0.40), reflecting the greater enhancement of secondary WSOC formation at the site in summer. Secondary WSOC concentrations estimated using EC tracer method were in the range $0.0{\sim}2.1\;{\mu}g/m^3$ (average $0.42\;{\mu}g/m^3$) and $0.0{\sim}1.1\;{\mu}g/m^3\;(0.24\;{\mu}g/m^3)$, respectively, accounting for $0{\sim}51.6%$ (average 16.8%) and $0{\sim}52.5%$ (average 13.1 %) of the measured WSOC concentrations in summer and winter. Sometimes higher WSOC/OC ratio in winter than that in summer could be attributed to two reasons. One is that the stable atmospheric condition often appears in winter, and the prolonged residence time would strengthen atmospheric oxidation of volatile organic compounds. The other is that decrease of ambient temperature in winter would enhance the condensation of volatile secondary WSOC on pre-existing aerosols. In summertime, atmospheric aerosols and WSOC concentrations showed bimodal size distributions, peaking at the size ranges $0.32{\sim}0.56\;{\mu}m$ (condensation mode) and $3.2{\sim}5.6\;{\mu}m$ (coarse mode), respectively. During the wintertime, atmospheric aerosols showed a bimodal character, while WSOC concentrations showed a unimodal pattern. Size distributions of atmospheric aerosols and WSOC with a peak in the size range $0.32{\sim}0.56\;{\mu}m$ were observed for most of the measurement periods. On January 17, however, atmospheric aerosols and WOSC exhibited size distributions with modal peaks in the size range $1.0{\sim}1.8\;{\mu}m$, suggesting that the aerosol particles collected on that day could be expected to be more aged, i.e, longer residence time, than the aerosols at other sampling periods.

• 한국대기환경학회지
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• 제30권5호
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• pp.449-460
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• 2014

Since the emergence of domestically produced automobiles in 1964, the number of automobiles in circulation in South Korea has increased constantly. With this rapidly increasing number of automobiles, automobile-induced environmental pollution has become an issue of great concern, especially with regard to air pollution. Of the carbon composites contained in automobile exhaust gas, PAHs are known to be carcinogenic and highly deleterious to humans and thus need to be urgently mitigated. To address this issue of PAHs, this study was conducted to estimate qualitative of particulate PAHs contained in carbon composites in automobile exhaust gas, by capturing all particulate matter discharged from the latter. To allow for differentiated analyses, the automobiles investigated were divided into 4 groups: gasoline vehicle, motocycle, diesel vehicle, and LPG vehicle. Samples were analyzed using two methods. First, in-depth analysis was performed on organic carbon (OC) and elemental carbon (EC) composites with analysis parameters, using the Thermal Optical Transmittance Method (NIOSH 5040). Second, for the examination of particulate PAHs, GC/MSD was used to analyze the 16 PAH species specified by the Environmental Protection Agency (EPA). The analyses yielded the findings that diesel vehicles had the highest mass concentration ($2,007{\mu}g/m^3$), followed by motocycle ($1,066{\mu}g/m^3$), LPG vehicle ($392{\mu}g/m^3$), and gasoline vehicles ($270{\mu}g/m^3$). The highest carbon concentrations in total particulate matter by vehicle weight were produced from LPG vehicle (79.8%), followed by gasoline vehicle (77.4%), motocycle (69.8%), and diesel vehicle (59.1%).

• 보존과학회지
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• 제33권4호
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• pp.283-295
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• 2017

건조물문화재의 생물피해 관련하여 먼저 기상요소를 직접 측정하고 국지 기상 특성을 파악하는 것은 매우 중요하다. 본 연구는 목조 건축물, 석조 건축물 생물피해가 확인되고, 지역적 기후 차이가 뚜렷한 충북 보은 법주사와 전남 순천 선암사를 비교 대상으로 기상요소 10가지 항목을 관측하였고 미세먼지(TSP)를 포집 분석하였다. 또한, 기상요소-미세먼지 간, 기상요소 간 상관성 분석을 실시하였다. 법주사의 국지 기상 특성은 일사량, 자외선량, 증발량이 많고 풍속이 빠르며 미세먼지 농도가 높은 반면 선암사의 국지 기상 특성은 기온, 습도, 이슬점온도, 기압이 높고 강수량, 강수일수가 많았다. 미세먼지의 원소분석결과, 선암사는 해염 입자가 추가로 발견되었고, 법주사에 비해 생체 입자와 철함유입자의 월별 빈도가 높게 나타났다. 상관성 분석 결과, 법주사는 풍속이, 선암사는 습도가 주요 기상인자로써 영향을 미치는 것으로 확인되었다. 이상의 결과로 선암사의 기상 특성은 각종 생물 성장에 유리하므로 건조물문화재의 생물학적 손상에 영향이 더 클 것으로 예상된다.

• 한국산업보건학회지
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• 제27권3호
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• pp.180-186
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• 2017

Objectives: The purposes of this study were to compare the surface resistance of cassettes according to the material, and to evaluate the wall deposition of carbon nanotubes(CNTs) by electrostatic loss in the inner wall of the cassette. Methods: Surface resistance was measured for three types of cassettes(25 mm polypropylene conductive cowl, 25 mm and 37 mm clear styrene cassettes) with a surface resistance meter. Also, electrostatic wall loss was measured at different weights of CNTs depending on the cassette. CNTs were laid on a weight dish with the cassette for five minutes to provide sufficient time to attach on the wall. Wipe sampling was performed to collect CNTs deposited on the wall and elemental carbon, known as a surrogate for CNTs, was analyzed. Results: The cassette with conductive materials(18% of black carbon) showed the lowest surface resistance($<1.21{\times}10^3{\Omega}$). Cassettes made from clear polystyrene showed the relatively highest surface resistance(25 mm: $10.02{\times}10^9{\Omega}$, 37 mm: $10.59{\times}10^9{\Omega}$). This means that particles are more likely to stick to the internal wall of styrene cassettes due to electrostatic electricity. This may lead to an underestimation of the airborne concentration of CNTs. The experiment showed that EC was not detected when using a 25 mm conductive cowl cassette, while EC was detected at the internal wall of 25 mm and 37 mm polystyrene cassettes. Conclusions: This study confirms that cassettes with a conductive cowl have low surface resistance and are more appropriate for CNT sampling. In addition, this finding could be applied for other types of particulate, especially regarding electrostatic charge and sampling.

• 자원환경지질
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• 제30권3호
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• pp.209-222
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• 1997

The Hoenam area, up the Taecheong lake, composed mainly of low grade coal-bearing metapelites within the Ogcheon Supergroup. These coal formations are developed discontinuously several hundred meters and swelling from 10 to 300 cm along the host metapelites. Although the formations have been mined for coal, but already mined out, and the formations were higher content (mean value of 42 samples) of environmental toxic elements as As (13 ppm). Ba (1.81 wt. %), Cd (2 ppm), Cr (188 ppm), Cu (87 ppm), Mo (214 ppm), Pb (25 ppm), Sb (3 ppm), Se (12 ppm), U (55 ppm), V (2124 ppm) and Zn (234 ppm) than the host metapelites and the NASC. The Al, Ti, Mg, K and Na contents in stream sediments derived from the Hando and Bugook mine area were highly concentrations than the samples from the Samseongjeil mine area. The mean value (wt. %) of Fe (10.07), Mn (0.15), Ca (0.84), P (0.18) and Ba (0.77) influenced by the Samseongjeil mine were higher than the other mine drainage sediments. The mean content (ppm) of environmental toxic elements in drainage sediments from the Samseongjeil mine were taken As (2083), Cu (447), Mo (202), Ni (720), Pb (42), U (250), V (1070) and Zn (2632), which are extremely high concentrations against NASC and EPA. Characteristics of elemental behavior and dispersion of the all toxic elements are the same as increased with increasing U, V, and Cu. Rare earth elements in the sediments are enriched with LREE (La, Ce and Nd) from the drainage on strong concentration of toxic elements. The pH of stream water is neutral, but pH of the sediments ranged from 4.92 to 6.93 (mean 6.22), those are slightly acid in the Hando mine area. Major elements in the host rocks at the Hoenam area are mostly depleted especially Ca, excepting Ti and Ba, normalized with NASC. The sediments were highly enriched of Ti, Fe, Mg, Mn and Ba, but depleted of Al, K, Ca, Na and P on the basis of host rocks and NASC. Minor and environmental toxic elements in the host rocks were strongly enriched all elements (As, Cd, Mo, Se, D, V and Zn), excepting Co, Ni and Sr. Enrichment index (mean value) about toxic elements (As, Cr, Cu, Fe, Ni, Pb and Zn) of the sediments in this area have taken 41.35 (Hando mine drainage; 2.73, Samseongjeil mine drainage; 113.14 and Bugook mine drainage; 8.19), those are seriously contaminated by environmental toxic elements.

• 자원환경지질
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• 제40권5호
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• pp.563-574
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• 2007

LIBS는 시료 표면에서 발생된 플라즈마로부터 방출되는 원자들의 분광선을 측정함으로써 물질의 화학적 조성을 감지, 확인, 정량화할 수 있는 최신의 분석기술로 기존의 전형적인 원소분석방법에 비해 현장분석기술로서의 더 많은 장점을 가지고 있다. LIBS는 최소한의 시료로 복잡한 분석과정을 피함으로 신속한 분석을 가능케 하고, 기기의 다방면적의 적용가능성과 단순함으로 인해 신속하게 가스, 고체, 액체상에서 다원소를 동시에 분석할 수 있는 레이저 기반의 분석기술로 지구화학적 분석, 탐사 혹은 환경분석에서 현장 이동성을 가진 센서로의 가능성 측면에서 매력적인 도구가 된다. 그러나 현장분석기술로서 토양환경에 적용하기에는 여전히 해결해야 할 문제들이 있다. 문헌연구를 통해 기본적인 작용원리인 플라즈마 형성과 물질붕괴과정을 고찰하고 현장분석기술로서 LIBS의 현 위치를 살펴본다. 또한 토양환경에 적용하기 위해 매질의 특성, 레이저 특성 및 분석신호에 영향을 미치는 다양한 인자들을 살펴보아 LIBS에 대한 기본적 이해를 돕고자 한다. 또한 분석에 미치는 영향 인자들을 보정해 분석 결과의 정확도, 정밀도 및 검출 한계 등 분석의 질을 향상 시킬 수 있는 기법 등을 다양한 문헌 연구를 통해 살펴봄으로써 추후 국내 토양환경분야의 LIBS 현장기술의 적용가능성을 고찰해보고자 한다.

• 한국대기환경학회지
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• 제26권6호
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• pp.606-615
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• 2010

This study aims to identify the characteristics of soil in Mongolia, one of the major Asian dust sources that influence the Korean Peninsula. Soil particle size was analyzed and the result shows that sand (57.5~97.3%) was identified prominently in most regions, followed by silt (2.5~34.7%) and clay (0.0~7.8%). Soil pH of the covered regions were in the range 7.1~10.1, either weak alkaline or strong alkaline. Analysis of ion species in the soil samples exhibited that $Na^+$ ($91.9\;mg\;kg^{-1}$), $Cl^-$ ($65.9\;mg\;kg^{-1}$), and $Ca^{2+}$ ($53.5\;mg\;kg^{-1}$) were detected more in the soil than other species such as ${SO_4}^{2-}$ ($19.2\;mg\;kg^{-1}$), ${NO_3}^-$ ($46.6\;mg\;kg^{-1}$), ${NH_4}^+$ ($3.9\;mg\;kg^{-1}$), $K^+$ ($22.0\;mg\;kg^{-1}$), and $Mg^{2+}$ ($10.2\;mg\;kg^{-1}$). As for heavy metal content in the soil, concentrations of soil-borne metals including Fe, Al, Ca, Mg, and K tended to be high, while metals that come from manmade sources Pb, Cd, Cr, V, and Ni were remarkably low. The concentration of organic carbon (OC) was relatively high at $15.9\;{\mu}g\;mg^{-1}$, while elemental carbon (EC), directly released in the process of fossil fuel combustion, was not detected at all or found in very small amounts. The result indicates that pollution from manmade sources scarcely occurred. The analysis results from this study may contribute to improving modeling accuracy by providing input data for Asian dust prediction models, and be used as base data for determining the process of physiochemical transformation of Asian dust during long-range transport.

• 대한환경공학회지
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• 제28권10호
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• pp.1038-1045
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• 2006

본 연구는 INAA와 ICP-MS의 두 가지 분석방법을 NIST SRM 2783과 실제의 대기입자 시료에 동시에 적용하고 그 결과를 비교하고자 하였다. NIST SRM 2783을 INAA와 ICP-MS로 분석하여 비교한 결과, INAA의 분석결과가 ICP-MS보다 정확하고 정밀한 것으로 나타났다. 또한, 공단지역에서 채취한 PM10 시료를 대상으로 역시 두 방법으로 분석하여 비교한 결과, 농도비의 평균이 Ba, Cu, K, Mg, Na, Sb는 $0.9{\sim}1.1$, Al, Co, Fe, Mn는 $0.8{\sim}1.2$, Se, Ti, Zn는 1.3 이상으로 나타났다. PM10 시료의 분석 대상 원소가 매우 넓은 농도범위를 보임에도 불구하고 회귀분석 및 paired t-test와 Wilcoxon signed-rank test 결과, 13종의 미량원소 중 Al, Ba, Co, Cu, Fe, K, Mn, Na, Sb는 두 방법 간의 분석결과가 잘 일치하는 것으로 나타났다.