• 대한환경공학회지
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• 제29권12호
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• pp.1360-1365
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• 2007

본 연구의 목적은 교량도로를 대상으로 배수받이에 퇴적된 퇴적물질을 대상으로 입경별로 유기물질 및 중금속 함량을 조사, 분석함으로서 강우 시 도로 퇴적물에 의한 비점오염부하의 기초 자료를 제공하고자 한다. 연구를 위한 퇴적물질 채취지점은 지방도로, 고속도로, 고가도로 상의 교량도로를 대표하는 지점 4개 지점을 선정하였다. 퇴적물질은 일정 입경범위로 범위(>2,000 ${\mu}m$, $1,000\sim2,000{\mu}m$, $850\sim1,000{\mu}m$, $425\sim850{\mu}m$, $212\sim425{\mu}m$, $125\sim212{\mu}m$, $90\sim125{\mu}m$, $75\sim90{\mu}m$, <75 ${\mu}m$)로 체분리 하였으며, 입경별로 용출 후 COD, T-N, T-P 등 일반 유기오염물질과 Fe, Cu, Cr, Pb 등의 중금속 농도를 분석하였다. 입경분포별 누적중량을 분석한 결과 $125\sim425{\mu}m$ 입경범위가 가장 많이 분포하는 것으로 조사되었으며, $<75{\mu}m$ 입경은 상대적으로 낮은 것으로 조사되었다. 조사지점 별 평균 오염물질 함량 범위는 COD $177\sim198.8$ g/kg(평균 77.6 g/kg), T-N $23\sim200$ mg/kg(평균 83 mg/kg), T-P $18\sim215$ mg/kg(평균 129 mg/kg)이었다. 중금속의 경우 Fe $1,508\sim5,612$ mg/kg(평균 3835 mg/kg), Cu $9.2\sim69.3$ mg/kg(평균 49 mg/kg), Cr $19.1\sim662.2$ mg/kg(평균 214 mg/kg), Pb $28.4\sim251.4$ mg/kg(평균 114 mg/kg)를 나타내었다. 입경별로는 오염물질 함량이 입경에 반비례하는 경향을 나타내었는데, 대체로 $75{\mu}m$ 이하의 입자가 오염물질 농도 함량이 가장 높았다. 연구 조사와 같이 교량도로 배수받이의 퇴적물질은 상당량의 미세입자 및 중금속이 다량 함유되어 있으므로 건기 시 주기적으로 퇴적물질을 제거를 통해서도 강우 시 비점오염부하를 상당량 저감시킬 수 있을 것으로 판단된다.

• 한국환경과학회지
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• 제21권7호
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• pp.855-863
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• 2012

This study analyzed mass concentrations of TSP, PM10 and PM2.5 and elemental constituents according to the isentropic backward trajectories of air parcel from Cheongwonin East Asia during the period January - October, 2011. Mass concentrations of the continental polluted airflow (CP) showed levels of TSP and PM10 mass concentrations higher than the continental background airflow (CB). Also, PM2.5 mass concentrations of anthropogenic fine particles ran higher in CP than in CB. The elemental constituents and elemental constituent ratio ended up varying depending on the origin of atmospheric aerosols generated. The average absolute content of elemental constituents reached its height in CB, the ratio of anthropogenically originating elements (PE) among the all elements (AE) analyzed marked a high in CP, and Mg+Na/AE reached its height in the oceanic airflow (OA). At the same time, TSP, PM10 and PM2.5 mass concentrations, the ratio of PM2.5/TSP and PE/AE element ratio ran higher in CP than CB. Episodes of large-scale transport of atmospheric pollutants as observed at Cheongwon were 8 cases and 22 days. The ratios of PM10, PM2.5 among TSP mass concentrations showed different results and the ratios of PM2.5 showed an increasing trend in the episodes of anthropogenic air pollution transport. Overall, dustfall episodes show a level of elemental constituents higher than those of anthropogenic air pollution.Dustfall episodes were observed to contain more of Fe, Al and Ca originating from continental soils and those of air pollution were observed to contain more of Zn, Mn, Cu and Pb. By difference in contents of absolute elemental constituents, episodes of anthropogenic air pollution showed a high PE/AE rate, and dustfall episodes a high SE/AE rate.

• Asian Journal of Atmospheric Environment
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• 제7권2호
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• pp.120-128
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• 2013

The concentration and composition of particulate matter (PM) in the atmosphere can directly reflect the environmental pollution. The atmospheric pollution in some Cameroonian cities is increasing with the industrial development and urbanization. Air pollution is inherently complex, containing PM of varied size and composition. This PM exists as a dynamic cloud interacting with sunlight and is modified by the meteorology. The reflectometer and the EDXRF spectrometry are applied to determine the concentration of some specific elements at four sites in the city of Yaound$\acute{e}$. The particular aim of the present work is to put in place data base on air pollution in urban area and elaborate regulations on the emissions issued to industrial and vehicle activities. This study provides an overview of the concentration of black carbon and some specific elements in the air, which have impacts on human health. The measurement was done by distinguishing the size of particle. So that, the particle with aerodynamic diameter between $2.5-10{\mu}m$ (so-called coarse particle) and aerodynamic diameter < $2.5{\mu}m$ (so-called fine particle) were considered to obtain more information about levels of the inhalable fraction of the location. The results obtained in four locations of the city of Yaound$\acute{e}$ show that the black carbon concentration is very considerable, the element sulfur is a major pollutant and the concentration of fine particle is very greater. The results obtained of fine and coarse filters range from $5-17{\mu}g/m^3$ and $10-18{\mu}g/m^3$ for the black carbon. S, Cu, Zn, Pb, Cd, As, Se and Hg are the specific findings of this work. The pollutants with a greater concentration are S, Pb, and Zn. These later seem to be non-uniformly, non-regular in some location and high compared to other countries. This work allows us to make a potential relation between pollutants and emission sources. In this framework, some suggestions have been proposed to reduce emissions for an improvement of the air quality in the environment and thus, the one of the city of Yaound$\acute{e}$.

• 한국환경과학회지
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• 제26권11호
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• pp.1297-1306
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• 2017

This study identified physical characteristics and aerosol particle sources of $PM_{10}$ and $PM_{2.5}$ in the industrial complex of Busan Metropolitan City, Korea. Samples of $PM_{10}$, $PM_{2.5}$ and also soil, were collected in several areas during the year of 2012 to investigate elemental composition. A URG cyclone sampler was used for collection. The samples were collected according to each experimental condition, and the analysis method of SEM-EDX was used to determine the concentration of each metallic element. The comparative analysis indicated that their mass concentration ranged from 1% to 3%. The elements in the industrial region that were above 10% were Si, Al, Fe, and Ca. Those below 5% were Na, Mg, and S. The remaining elements (1% of total mass) consisted of elements such as Ni, Co, Br and Pb. Finally, a statistical tool was applied to the elemental results to identify each source for the industrial region. From a principal components analysis (SPSS, Ver 20.0) performed to analyze the possible sources of $PM_{10}$ in the industrial region, five main factors were determined. Factor 1 (Si, Al), which accounted for 15.8% of the total variance, was mostly affected by soil and dust from manufacturing facilities nearby, Factors 2 (Cu, Ni), 3 (Zn, Pb), and 4 (Mn, Fe), which also accounted for some of variance, were mainly related to iron, non-ferrous metals, and other industrial manufacturing sources. Also, five factors determined to access possible sources of $PM_{2.5}$, Factor 1 (Na, S), accounted for 13.5% of the total variance and was affected by sea-salt particles and fuel incineration sources, and Factors 2 (Ti, Mn), 3 (Pb, Cl), 4 (K, Al) also explained significant proportions of the variance. Theses factors mean that the $PM_{2.5}$ emission sources may be considered as sources of incineration, and metals, and non-ferrous manufacturing industries.

• 한국식품영양과학회지
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• 제23권3호
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• pp.402-408
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• 1994

인체의 혈장 저밀도 지단백(LDL)은 관상동맥경화 발병의 주 요인이다. 그러나 최근의 연구들은, 정상적인 LDL은 산소 자류라디칼에 의해 쉽게 산화되며, 결과 LDL 수용채와 결합하지 못한다고 밝히고 있다. 따라서 이 변형된 형태의 산화된 LDL은 macrophage scavernger receptor에 의해 인식되어 foam cell을 형성하여, 동맥혈관이 좁아지는 역할을 수행한다고 알려지고 있다. 지리과 산화에는 지방산이 중요한 작용을 하므로, 한국인의 LDL의 지방산 조성을 분석하여 서양인과 비교하였다. 결과, 한국인의 불포화 지방산의 비율이 총 지방산 함량의 약 30%인 반면 서양인은 약 70%의 분포를 갖고 있는 것으로 발표되었다. 따라서 한국인이 서양인에 비해 LDL의 산화에 대한 영향을 적게 받을 수 있으며, 따라서 동맥경화나 심장병의 발생률이 훨씬 적을 것으로 결론을 내릴 있다. 정상적인 LDL을 황산구리와 함께 배양하여, 지방의 산화를 유도하였으며 이의 정도를 지방산 산화의 생성물인 TBARS를 측정하여, LDL이 산화될 때 생성되는 자유라디칼의 양을 측정하므로서 비교하였다. 이 때, 항상화제인 비타민 C; 비타민 E와 히알우로닉산을 첨가하면 LDL의 산화가 억제되는 효과를 확인하였다. 자유 라디탈이 증가함에 따라 산화의 정도도 증가하였으며, 자유라디칼 형성의 경시적 변화는 TBARS와 유사하였다. 따라서 luminometer에 의한 자유라디칼의 정량은 TBARS에 의한 것보다 훨씬 간편한 것으로 나타났다.

• 한국대기환경학회지
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• 제24권4호
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• pp.439-454
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• 2008

The purpose of this study was to extensively identify $PM_{10}$ sources and to estimate their contributions to the study area, based on the analysis of the $PM_{10}$ mass concentration and the associated inorganic elements, ions, and total carbon. The contribution of $PM_{10}$ sources was estimated by applying a receptor method because identifying air emission sources were effective way to control the ambient air quality. $PM_{10}$ particles were collected from May to November 2007 in the Yongin-Suwon bordering area. $PM_{10}$ samples were collected on quartz filters by a $PM_{10}$ high-volume air sampler. The inorganic elements (Al, Mn, V, Cr, Fe, Ni, Cu, Zn, Cd, Pb, Si, Ba, Ti and Ag) were analyzed by an ICP-AES after proper pre-treatments of each sample. The ionic components of these $PM_{10}$ samples ($Cl^_$, $NO_3^-$, $SO_4^{2-}$, $Na^+$, $NH_4^+$, $K^+$, $Ca^{2+}$, and $Mg^{2+}$) were analyzed by an IC. The carbon components (OC1, OC2, OC3, OC4, OP, EC1, EC2 and EC3) were also analyzed by DRI/OGC analyzer. Source apportionment of $PM_{10}$ was performed using a positive matrix factorization (PMF) model. After performing PMF modeling, a total of 8 sources were identified and their contribution were estimated. Contributions from each emission source were as follows: 13.8% from oil combustion and industrial related source, 25.4% from soil source, 22.1% from secondary sulfate, 12.3% from secondary nitrate, 17.7% from auto emission including diesel (12.1%) and gasoline (5.6%), 3.1% from waste incineration and 5.6% from Na-rich source. This study provides information on the major sources affecting air quality in the receptor site, and therefore it will help us maintain and manage the ambient air quality in the Yongin-Suwon bordering area by establishing reliable control strategies for the related sources.

• 한국지구과학회지
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• 제23권6호
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• pp.514-525
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• 2002

본 연구는 서울시 북동지역의 군자동에 위치한 세종대학교를 중심으로 2001년 봄철 3월에서 4월까지 PM2.5와 PM10을 채취하여, 이들과 결합된 중금속 성분들에 대한 농도분포의 특성을 살펴보았다. 전체 관측기간 동안 산출된 PM2.5, PM10, 조대입자 영역(PM10-PM2.5)의 평균농도는 49.3${\pm}$29.2, 95.5${\pm}$46.1, 50.5${\pm}$35.0 ${\mu}g$/m$^3$으로 나타났다. 연구대상지역의 중금속 오염도를 살펴보기 위해 부화계수(enrichment factor: EF)를 비교한 결과, 미세 및 조대입자 모두에서 Zn, V, Cr, Pb, Cu, Ni, Co, Mo 등의 중금속 성분들의 EF값이 수십, 수백의 범위에 달할 정도로 오염의 수준이 심각하다는 것을 확인할 수 있었다. 미세/조대입자 영역간에 형성되는 농도비를 비교한 결과, Zn, Cr, Pb, Ni 등이 미세입자 영역에서 뚜렷하게 더 높은 농도를 보이는 것으로 확인되었다. 중금속 농도에 대해 보다 세부적인 분석을 실시한 결과, 중금속 성분들의 농도는 상당 수준 증가하는데, 이와 같은 증가는 황사의 영향을 상당 수준 받는 것으로 나타났다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.409-409
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• 2014

Recently hexagonal boron nitride (h-BN), III-V compound of boron and nitrogen with strong covalent $sp^2$ bond, is a 2 dimensional insulating material with a large direct band gap up to 6 eV. Its outstanding properties such as strong mechanical strength, high thermal conductivity, and chemical stability have been reported to be similar or superior to graphene. Because of these excellent properties, h-BN can potentially be used for variety of applications such as dielectric layer, deep UV optoelectronic device, and protective transparent substrate. Ultra flat and charge impurity-free surface of h-BN is also an ideal substrate to maintain electrical properties of 2 dimensional materials such as graphene. To synthesize a single or a few layered h-BN, chemical vapor deposition method (CVD) has been widely used by using an ammonia borane as a precursor. Ammonia borane decomposes into hydrogen (gas), monomeric aminoborane (solid), and borazine (gas) that is used for growing h-BN layer. However, very active monomeric aminoborane forms polymeric aminoborane nanoparticles that are white non-crystalline BN nanoparticles of 50~100 nm in diameter. The presence of these BN nanoparticles following the synthesis has been hampering the implementation of h-BN to various applications. Therefore, it is quite important to grow a clean and high quality h-BN layer free of BN particles without having to introduce complicated process steps. We have demonstrated a synthesis of a high quality h-BN monolayer free of BN nanoparticles in wafer-scale size of $7{\times}7cm^2$ by using CVD method incorporating a simple filter system. The measured results have shown that the filter can effectively remove BN nanoparticles by restricting them from reaching to Cu substrate. Layer thickness of about 0.48 nm measured by AFM, a Raman shift of $1,371{\sim}1,372cm^{-1}$ measured by micro Raman spectroscopy along with optical band gap of 6.06 eV estimated from UV-Vis Spectrophotometer confirm the formation of monolayer h-BN. Quantitative XPS analysis for the ratio of boron and nitrogen and CS-corrected HRTEM image of atomic resolution hexagonal lattices indicate a high quality stoichiometric h-BN. The method presented here provides a promising technique for the synthesis of high quality monolayer h-BN free of BN nanoparticles.

• 한국대기환경학회지
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• 제22권5호
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• pp.590-603
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• 2006

Size-and time-resolved aerosol samples were collected using an eight-stage Davis rotating unit for monitoring (DRUM) sampler from 23 March to 29 April 2001 at Gosan, Jeju Island, Korea, which is one of the super sites of Asia-Pacific Regional Aerosol Characterization Experiment(ACE-Asia). These samples were analyzed using synchrotron X-ray fluorescence for 3-hr average concentrations of 19 elements including Al, Si, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Br, Rb, and Pb. The size-resolved data sets were then analyzed using the positive matrix factorization(PMF) technique to identify possible sources and estimate their contributions to particulate matter mass. PMF analysis uses the uncertainty of the measured data to provide an optimal weighting. Twelve sources were resolved in eight size ranges($0.09{\sim}12{\mu}m$) and included continental soil, local soil, sea salt, biomass/biofuel burning, coal combustion, oil combustion, municipal incineration, nonferrous metal source, ferrous metal source, gasoline vehicle, diesel vehicle, and volcanic emission. The PMF result of size-resolved source contributions showed that natural sources represented by local soil, sea salt, continental soil, and volcanic emission contributed about 79% to the predicted primary particulate matter(PM) mass in the coarse size range ($1.15{\sim}12{\mu}m$) while anthropogenic sources such as coal combustion and biomass/biofuel burning contributed about 58% in the fine size range($0.56{\sim}2.5{\mu}m$). The diesel vehicle source contributed mostly in ultra-fine size range($0.09{\sim}0.56{\mu}m$) and was responsible for about 56% of the primary PM mass.

• 생태와환경
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• 제43권1호
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• pp.11-18
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• 2010

본 연구의 대상지역인 탄천은 한강에서 합류되는 대표적인 도심지역 하천으로 주변 지역의 점오염원 및 비점 오염원을 통해 오염물질이 지속적으로 유입되고 있다. 본 연구논 전 구간에 걸쳐 하천수와 퇴적물의 오염도 평가를 수행하였다. 또한 이 결과를 바탕으로 두 지점을 선정해 미생물 두 종과 개량송사리에 대한 퇴적물 공극수(sediment pore-water) 생태독성시험을 수행하였다. 하천의 수질측정 결과 상류에서 하류로 갈수록 오염이 심해지는 경향을 보였으며, 공공하수처리시설 방류수 유출지점에서 그 상승폭이 증가하여, 하천수에 대한 주요 오염원으로 판단할 수 있다. 그러나 하천수 내의 중금속은 그 오염도가 낮은 수준으로 하천수질기준을 초과하지 않았으며 생태계에 영향을 야기할만한 수준은 아닌 것으로 판단하였다. 퇴적물 중금속은 대부분이 극외의 퇴적물 권고수준(ISQG) 미만이었으나 일부 구역에서 비소와 구리의 농도가 높게 관찰되었다. 또한, 구리의 경우 전 구간에 걸쳐 높은 농도를 보이고 있다. 구리는 생태독성이 높은 중금속이므로 이에 대한 우선적인 관리가 요구된다. 한편 퇴적물 중금속 농도는 하류로 갈수록 낮아지는 경향을 보였는데 이는 하류 지점 토성에 모래 함량에 의한 것으로 사료된다. 또한 유기물도 모래 함량과 반비례 관계로 대교 부근과 공공하수처리장 방류수 유입 이전 지점에서 높은 수치를 나타내어, 퇴적물의 토성에 의해 오염도가 변화되는 양상을 나타내었다. 생태독성시험 퇴적물 채취지점에 대한 질소와 인의 측정 결과 모두 높은 수치를 나타내었으며 $NH_4$-N을 많이 함유하고 있어 오염물이 대상 지역 인근에서 유입됨을 판단할 수 있었다. 공극수 독성시험 결과 대교 부근 지점에서는 독성 영향이 낮았으나, 공공하수처리시설 방류수 유입지점에서 치사율이 관찰되었다. 따라서, 실험대상 퇴적물은 생태위해우려가 있는 수준은 아닌 것으로 평가되었다. 그러나 퇴적물에서 용출되는 독성물질들은 주로 퇴적물과 하천수의 경계에서 살아가는 초기 생장단계의 유생생물들에게 영향을 미칠 가능성이 있으므로 수생태계 보존을 위한 관리대책이 요구된다.