• 한국대기환경학회지
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• 제21권1호
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• pp.131-140
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• 2005

To investigate secondary carbonaceous species within PM$_{10}$ and PM$_{2.5}$ in Seoul urban Metropolitan Area (SMA), Korea. atmospheric particulate matters samples were collected at two sites of SMA at UOS (The University Of Seoul station) sites and IHU (InHa University of Incheon station) during the period of 4 to 14 January and 12 to 22 May, 11 to 15 August 2004, and their characteristics were qualitatively discussed. during January and May and August of 2004. Daily average mass concentration 0.095 mg/㎥ in PM$_{10}$ and 0.053 mg/㎥ in PM$_{2.5}$ for mass respectively. were observed in SMA. The concentrations of carbonaceous species contributed 18.4% and 16.4% of PM$_{2.5}$ and PM$_{10}$ during the sampling period, respectively, of which OC accounted for 68% and 52% more of the total carbon (TC). OC and EC concentrations and their mass percentages were higher in PM$_{2.5}$ than in PM$_{10}$ which could be attributed to generation process. Organic aerosols would constitute up to 38% of PM$_{2.5}$ based on the evaluation of 1.6 for the ratio of OC to organic particulate. Secondary organic carbon (SOC) were estimated to be more than 13% and up to 68% of total OC based on the minimum OC/EC ratio of 1.06/1.11 using least square method. Comparisons of OC and EC with trace elements. As results of carbonaceous species analysis, the dominant factor in view of fine particle (PM$_{10}$/PM$_{2.5}$) is primary emission source such as mobile, fossil fuel combustion etc. during winter time in SMA. But in summer periods, remarkable fine particle increasing factor was secondary organic carbon dependent to photochemical reaction. reaction.n. reaction.

• 한국대기환경학회지
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• 제31권3호
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• pp.209-222
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• 2015

Fine and coarse PM had been collected by LVCI (low volume cascade impactor) and HVAS (high volume air sampler) during January 1989 to April 2012 at Kyung Hee University, Global Campus located on the boarder of Yongin and Suwon. The database of PM mass concentration was constructed and then intensively and extensively investigated to understand monthly, seasonal, and annual patterns of each PM behavior. Especially the study separated all the PM data into the 5 Period Zones, which were classified on the basis of social, political, and environmental issues that might be influencing local ambient air quality during the monitoring period. The overall $PM_{10}$ level had been continuously decreased until 2005 and after then was staggering due to rapidly increasing $PM_{2.5}$ level in $PM_{10}$. The annual average of $PM_{2.5}$ concentration varied from $34.3{\mu}g/m^3$ to $59.0{\mu}g/m^3$, which were much higher than the 2015 ambient air quality standard. The $PM_{2.5}$ level was strongly associated with haze events, while both $PM_{10}$ and $PM_{2.5}$ levels were associated with Yellow storm events. Daily concentrations of $PM_{2.5}$ were ranged $13.1{\sim}212.9{\mu}g/m^3$ in haze days and $33.6{\sim}124.6{\mu}g/m^3$ in Asian dust days. The study also intensively investigated annual and seasonal patterns of $PM_{2.5}/PM_{10}$ ratios.

• 한국환경보건학회지
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• 제34권1호
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• pp.34-41
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• 2008

The objective of this study is to provide the research data on the actual concentrations of $PM_{10},\;PM_{2.5},\;PM_1\;and\;CO_2$ in Seoul subway carriages. Mean concentrations of $PM_{10},\;PM_{2.5}\;and\;PM_1,\;and\;CO_2$ in subway carriages were investigated at levels of $215.1{\pm}101.4{\mu}g/m^3,\;86.9{\pm}38.6{\mu}g/m^3,\;27.0{\pm}11.4{\mu}g/m^3,\;and\;1,588{\pm}714ppm$, respectively. The mean concentrations in subway carriages were higher when the train ran on an underground track rather than on an above ground track. The measured concentration of particulate matter varied with the time of day and was highest in the morning, followed by noon and evening while the $CO_2$ concentration was highest in the morning, followed by evening and noon. In relation to correlation among the pollutants: the correlation between $PM_{10}\;and\;PM_{2.5}$ was 0.92, and that between $PM_{2.5}\;and\;PM_1$ was 0.94. The inclusion rate of $PM_{2.5}\;to\;PM_{10}$ was $41{\pm}7%$ and that of $PM_1\;to\;PM_{2.5}\;was\;32{\pm}4%$. In addition, the $CO_2$ concentration had a positive relation with the number of people in a carriage, whereas the concentration of $PM_{10}$ had negative correlation to the number of people. In relation to these two pollutants we calculated using a regression equation (34.06+0.04$CO_2$(ppm)-0.09 PM10$({\mu}g/m^3)$($R^2$=0.30, p<0.01, n=707), that a maximum number of 61 persons would ensure that each pollutant is maintained below the criteria level, applicable to subway stations.

• 한국대기환경학회지
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• 제31권5호
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• pp.411-429
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• 2015

The Korea Ministry of Environment has established an air quality standard for $PM_{2.5}$ in 2012 and it is effective from January 2015. In this study, we review various aspects of $PM_{2.5}$ in China, including its measurement, modeling, source apportionment, and health effect, and suggest future research directions for $PM_{2.5}$ studies in Korea. Measurements studies for $PM_{2.5}$ have examined organic marker compounds and $^{14}C$ as well as inorganic aerosols for distinguishing sources. Modeling results supported that the control of $PM_{2.5}$ pollution in big city needs effective cooperation between city and its surrounding regions. The major $PM_{2.5}$ sources in China have been identified to be secondary sulfur, motor vehicle emissions, coal combustion, dust, biomass burning, and industrial sources, however, they have seasonal dependency. Especially, the severe haze pollution event during January 2013 over eastern and northern China was driven to a large extent by secondary aerosol formation. Short-term exposure to $PM_{2.5}$ is strongly associated with the increased risk of morbidity and mortality from cardiovascular and respiratory diseases, as well as total non-accidental mortality. Considered previous $PM_{2.5}$ studies in China, analysis of specific organic species using online measurement, chamber experiment for secondary aerosol formation mechanism, and development of parameterizing this process in the model are needed to elucidate factors governing the abundance and composition of $PM_{2.5}$ in Korea.

• 생명과학회지
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• 제19권5호
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• pp.553-560
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• 2009

$P_{1/2}$ 값을 참고로 비교한 알긴산, 폴리글루론산 및 폴리만뉴론산의 금속이온들에 대한 상대적인 친화성은 다음과 같다; 1) 알긴산: $Cu^{2+}$ > $Cd^{2+}$ > $Pb^{2+}$ > $Fe^{3+}$ >> $Zn^{2+}$ > $Sr^{2+}$ > $Ca^{2+}$ > $Co^{2+}$ >> $Cr^{6+}$ > $Mn^{2+}$ >> $Hg^{2+}$, $Mg^{2+}$, $Rb^+$, 2) 폴리글루론산: $Cd^{2+}$ > $Cu^{2+}$ > $Pb^{2+}$ > $Fe^{3+}$ >> $Ca^{2+}$ > $Sr^{2+}$, $Zn^{2+}$, $Co^{2+}$ >> $Mn^{2+}$ > $Cr^{6+}$ >> $Hg^{2+}$, $Mg^{2+}$, $Rb^+$, 그리고 3) 폴리만뉴론산: $Cd^{2+}$, $Cu^{2+}$ > $Fe^{3+}$ > $Pb^{2+}$ > $Ca^{2+}$ > $Zn^{2+}$ > $Sr^{2+}$ > $Co^{2+}$ > $Cr^{6+}$ >> $Mn^{2+}$ >> $Hg^{2+}$, $Mg^{2+}$, $Rb^+$. 알기산 1 g에 흡착하는 $Cd^{2+}$, $Cu^{2+}$, $Fe^{3+}$, $Pb^{2+}$, 및 $Zn^{2+}$의 양은 $363.5{\pm}45.0$, $226.3{\pm}9.2$, $1,299.4{\pm}$81.3, 500.7${\pm}$27.7 및 165.9${\pm}$11.4 mg이었으며, 폴리글루론산 1g에 흡착하는 $Cd^{2+}$, $Cu^{2+}$, $Fe^{3+}$, $Pb^{2+}$, 및 $Zn^{2+}$의 양은 354.5${\pm}$26.5, 177.6${\pm}$8.7, 1,288.6${\pm}$60.1, 424.0${\pm}$7.4 및 140.2${\pm}$28.5 mg이었으나, 폴리만뉴론산 1 g에 흡착하는 $Cd^{2+}$, $Cu^{2+}$, $Fe^{3+}$, $Pb^{2+}$, 및 $Zn^{2+}$의 양은 329.0${\pm}$10.3, 226.9${\pm}$1.9, 1,635.6${\pm}$11.1, 419.8${\pm}$12.6 및 251.0${\pm}$49.1 mg이었다. 폴리만뉴론산은 알긴산보다 높은 용해도와 폴리글루론산보다 높은 금속이온에 대한 친화성 때문에 독성이 높은 중금속이나 경제성이 높은 금속을 선택적으로 분리하는 데 사용할 수 있을 것이다.

• 한국축산시설환경학회지
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• 제12권3호
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• pp.115-122
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• 2006

본 연구는 터널환기 무창육계사의 계사내부의 위치별 먼지 농도 분포와 배기홴에서 배출된 먼지의 확산범위를 알아보고자 수행하였으며 결과는 다음과 같다. 1. 입기구 방향의 계사 1/4 지점의 먼지농도는 TSP의 경우 $301.0{\sim}1,366.0\;{\mu}g/m^3$으로 입기구의 위치에 따라 차이가 있었다. 2. 터널홴 앞 3m 지점에서는 TSP $2065.8{\sim}3,092.2\;{\mu}g/m^3$, PM 2.5 $27.6{\sim}36.3\;{\mu}g/m^3$, PM 1.0 $8.3{\sim}11.3\;{\mu}g/m^3$으로 입기구에 비하여 증가하였다. 3. 배기홴으로부터 3m의 지점의 먼지 배출량은 TSP $354.8{\sim}574.8\;{\mu}g/m^3$으로 매우 높았으며 PM10 $94.4{\sim}156.2\;{\mu}g/m^3$, PM2.5 $14.6{\sim}18.0\;{\mu}g/m^3$, PM1.0 $6.0{\sim}6.4\;{\mu}g/m^3$ 이었다. 4. 배기홴으로부터 50m 떨어진 지점에서의 분진농도는 TSP $25.1\;{\mu}g/m^3$, PM10 $8.8\;{\mu}g/m^3$, PM2.5 $5.6\;{\mu}g/m^3$, PM1.0 $4.9\;{\mu}g/m^3$으로 매우 낮은 분진농도를 보였다. 5. 입기구와 배기구 간 분진농도의 차이는 TSP의 경우 입기구에서 $317.9\;{\mu}g/m^3$인데 비하여 배기구는 $2,678.5\;{\mu}g/m^3$로 8.42배 높았으며 PM10 7.4배, PM2.5 3.4배, PM1.0 1.6배 높았다. 6. 배기홴으로부터 거리별 분진의 배출농도는 3m 지점에서 $446.6\;{\mu}g/m^3$ 이었으나 20 m 지점에서는 $156.3\;{\mu}g/m^3$로 34.9% 수준이었고 PM10 34.9%, PM2.5 48.7%, PM1.0 86.8% 수준이었다.

• Journal of the Korean Wood Science and Technology
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• 제15권2호
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• pp.26-52
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• 1987

우리나라에 분포도(分布度)가 높은 산공재(散孔材) 중에서 구조용재(構造用材)로서 뿐만 아니라 각종 특수용재(特殊用材)로서 이용도(利用度)가 높은 자작나무과(科) 3속(屬) 7수종(樹種)을 비롯한 6속(屬) 10수종(樹種)의 주요(主要) 구성요소(構成要素)의 방사방향(放射方向)에 따른 변동(變動)을 조사(調査)하였던 바 얻어진 결과(結果)를 요약(要約)하면 다음과 같다. 주요(王要) 구성요소(構成要素)의 치수는 수에 가까운 부위(部位)에서 일정(一定) 년륜(年輪)까지 급격히 증가(增加)한 후 거의 안정(安定)되는 직선형(直線型)(Type I), 완만하게 계속 증가(增加)하는 곡선형(曲線型)(Type II) 및 서서히 감소(減少)하는 포물선형(抛物線形)(Type III)으로 구분(區分)되며 동일수종내(同一樹種內)에서도 요소별(要素別)로 서로 다른 형(型) 공존(共存)하였다. 2. 목섬유(木織維)길이의 변이형(變異型)과 크기는 Type I은 자작나무 $1.35{\pm}0.10mm$, 거제수나무 $1.20{\pm}0.13mm$, 박달나무 $1.03{\pm}0.10mm$, 서어나무 $1.18{\pm}0.37mm$, 오리나무 $1.06{\pm}0.01mm$, 산벚나무 $0.81{\pm}0.16mm$였고, Type II는 사스래나무 $1.34{\pm}0.19mm$, 물박달나무 $1.20{\pm}0.29mm$였으며 Type III은 감나무 $0.95{\pm}0.13mm$였다. 목섬유(木纖維)의 폭(幅)의 변이형(變異型)과 크기는 Type I은 서어나무 $18.7{\pm}1.8{\mu}m$, 오리나무 $18.5{\pm}1.1{\mu}m$, 고로쇠나무 $14.5{\pm}2.4{\mu}m$였고, Type II는 사스래나무 $19.3{\pm}1.4{\mu}m$, 박달나무 $17.5{\pm}1.9{\mu}m$, 산벚나무 $14.8{\pm}5.4{\mu}m$였으며, Type III은 자작나무 $19.1{\pm}1.1{\mu}m$, 물박달나무 $20.3{\pm}3.4{\mu}m$, 거제수나무 $18.6{\pm}2.8{\mu}m$, 감나무 $18.9{\pm}4.3{\mu}m$였다. 3. 도관요소(導管要素) 길이의 변이형(變異型)과 크기는 Type I이 자작나무 $0.62{\pm}0.02mm$, 사스래나무 $0.90{\pm}0.09mm$, 박달나무 $0.64{\pm}0.08mm$, 산벚나무 $0.43{\pm}0.05mm$, 고로쇠나무 $0.31{\pm}0.03mm$였고 Type II는 물박달나무 $0.72{\pm}0.22mm$, 오리나무 $0.63{\pm}0.01mm$, 감나무 $0.17{\pm}0.06mm$였으며, Type III은 거제수나무 $0.75{\pm}0.10mm$, 서어나무 $0.66{\pm}0.16mm$였다. 도관요소(導管要素) 방사방향(放射方向) 직경(直徑)의 변이형(變異型)과 크기는 Type I이 자작나무 $58.7{\pm}11.3{\mu}m$, 서어나무 $67.1{\pm}10.1{\mu}m$, 오리나무 $60.0{\pm}10.3{\mu}m$ 였고, Type II가 사스래나무 $100.7{\pm}10.7{\mu}m$, 거제수 나무 $108.9{\pm}16.6{\mu}m$, 박달나무 $79.1{\pm}17.3{\mu}m$, 산벚나무 $47.5{\pm}21.3{\mu}m$, 감나무 $141.2{\pm}59.5{\mu}m$였으며, Type III은 물박달나무 $115.0{\pm}17.4{\mu}m$, 고로쇠나무 $57.1{\pm}11.4{\mu}m$였다. 도관요소(導管要素) 접선방향(接線方向) 직경(直徑)이 변이형(變異型)과 크기는 Type I이 자작나무 $54.8{\pm}13.5{\mu}m$, 서어나무 $57.1{\pm}11.7{\mu}m$, 오리나무 $44.9{\pm}13.0{\mu}m$였고, Type II는 사스래나무 $76.5{\pm}16.9{\mu}m$, 거제수나무 $87.1{\pm}17.3{\mu}m$, 박달나무 $65.6{\pm}9.2{\mu}m$, 산벚나무 $44.9{\pm}13.0{\mu}m$, 고로쇠나무 $34.8{\pm}10.4{\mu}m$였으며, Type III은 물박달나무 $86.0{\pm}13.6{\mu}m$, 감나무 $129.3{\pm}34.5{\mu}m$였다. 단위면적당(單位面積當) 관공(管孔)의 분포(分布)는 자작나무 $54.4{\pm}3.5$개, 사스래나무 $23.0{\pm}2.8 $개, 물박달나무 $19.5{\pm}2.5$개, 거제수나무 $20.8{\pm}2.6$개 박달나무 $17.6{\pm}2.7$, 서어나무 $87.5{\pm}14.7$개, 오리나무 $79.9{\pm}11.6$개, 산벚나무 $223.1{\pm}33.2$개, 고로쇠나무 $40.6{\pm}2.4$개, 감나무 $6.6{\pm}1.5$개였다. 4. 계단상(階段狀) 천공판(穿孔板)을 갖는 수종(樹種)의 천공판(穿孔板) 길이의 변이형(變異型)과 크기는 Type I은 자작나무 $143.5{\pm}16.4{\mu}m$, 거제수나무 $139.6{\pm}16.6{\mu}m$, 오리나무 $123.3{\pm}20.6{\mu}m$였고, Type II는 사스래나무 $144.9{\pm}17.9{\mu}m$, 물박달나무 $140.4{\pm}23.4{\mu}m$였으며, Type III은 박달나무 $108.7{\pm}19.7{\mu}m$였다. 판공판상(穿孔板上) bar수(數)의 변이형(變異型)과 수(數)는 Type I은 거제수나무 13.8{\pm}2.3개, 박달나무 $11.6{\pm}2.3$개였고, Type II은 물박달나무 $15.l{\pm}6.2$개였으며, Type III은 자작나무 $16.6{\pm}8.3$개, 사스래나무 $10.1{\pm}1.7$개, 오리나무 $17.1{\pm}7.9$ 개였다. 5. 방사조직(放射組織) 높이의 변이형(變異型)과 크기는 Type I이 사스래나무 $187.3{\pm}46.5{\mu}m$, 거제수나무 $209.9{\pm}48.4{\mu}m$였고, Type II는 자작나무 346.3{\pm}, $83.4{\mu}m$, 서어나무 $297.0{\pm}87.0{\mu}m$, 오리나무 $387.3{\pm}84.7{\mu}m$, 고로쇠나무 $244.8{\pm}74.0{\mu}m$였으며, Type III은 물박달나무 $233.7{\pm}66.1{\mu}m$, 박달나무 $172.9{\pm}47.9{\mu}m$, 산벚나무 $361.8{\pm}88.8{\mu}m$, 감나무 $304.8{\pm}87.3{\mu}m$였다. 방사조직(放射組織) 폭(幅)의 변이형(變異型)과 크기는 Type I이 거제수나무 $25.5{\pm}5.3{\mu}m$, 서어나무 $44.9{\pm}16.1{\mu}m$, 오리나무 $27.3{\pm}8.3{\mu}m$였고, Type II는 자작나무 $29.8{\pm}6.3{\mu}m$, 사스래나무 $23.6{\pm}5.0{\mu}m$, 물박달나무 $33.3{\pm}8.9{\mu}m$, 박달나무 $21.9{\pm}9.3{\mu}m$, 산벚나무 $39.2{\pm}10.1{\mu}m$, 고로쇠나무 $35.2{\pm}8.9{\mu}m$였으며, Type III은 감나무 $44.2{\pm}7.6{\mu}m$였다. 6. 목섬유(木纖維), 도관요소(導管要素), 방사조직(放射組織)의 치수의 변동(變動)을 고려(考慮)하여 미성숙재(未成熟材)와 성숙재(成熟材)를 구분(區分)하면 자작나무 45년륜(年輪), 사스래나무 43년륜(年輪), 물박달나무 34년륜(年輪), 거제수나무 53년륜(年輪), 박달나무 38년륜(年輪), 서어나무 44년륜(年輪), 오리나무 31년륜(年輪), 산벚나무 24년륜(年輪), 고로쇠나무 47년륜(年輪), 감나무 30년륜(年輪)이었다.

• 한국의학물리학회지:의학물리
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• 제20권4호
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• pp.244-252
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• 2009

자화율(susceptibility) 및 강자성체(ferromagnetic body)에 의한 인공물(artifact) 영향을 줄이기 위하여 중심주파수(center frequency) 정렬과 송 신호강도(transmission gain)값의 변화로 영상의 질을 보상하고자 한다. 본원에 내원한 환자 중 총 30명에 대하여 두 경부(head and neck)질환을 의심한 환자 중 남자 15명, 여자 15명으로 평균나이는 45세이었다. 사용된 장비는 GE 1.5T unit (GE, General Electric medical system, High Density)를 사용하여 Transmission gain (TG) 값을 평균 몸무게 60 kg을 기준으로 70, 90, 110, 130, 150까지 변환하여 검사를 하였다(p<0.05). 본 연구의 결과로서, 조영제 주입 전과 후의 지방소거 결과는 TG (70, 90, 110, 130, $150=3.23{\pm}0.35$, $4.31{\pm}0.02$, $4.23{\pm}0.21$, $5.12{\pm}0.25$, $7.13{\pm}0.72$, $8.31{\pm}0.01$, $5.21{\pm}0.15$, $6.14{\pm}0.08$, $5.23{\pm}0.72$, $5.91{\pm}0.06$)값에 다른 점수 분포를 나타났다(p<0.05). 절대값 대조도대 잡음비는 (TG, CNRpre, CNRpost, 70: $-1.44{\pm}0.11$, $-2.7{\pm}0.04$, 90: $-2.18{\pm}0.42$, $-4.41{\pm}0.43$, 110: $-2.89{\pm}0.43$, $-5.23{\pm}0.02$, 130: $-2.34{\pm}0.05$, $-5.26{\pm}0.01$, 150: $-2.09{\pm}0.08$, $-3.87{\pm}0.12$)을 얻었다(p<0.05). 본 실험에서 중심주파수 조정과 송 신호강도(transmission gain)값의 변화에 따라 인공물이 있을 때 영상의 질을 보상할 수 있다는 것을 확인하였다.

• 한국환경과학회지
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• 제26권6호
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• pp.767-778
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• 2017

This research investigates the characteristics of metallic and ionic elements in $PM_{10}$ and $PM_{2.5}$ on haze day and non-haze day in Busan. $PM_{10}$ concentration on haze day and non-haze day were 85.75 and $33.52{\mu}g/m^3$, respectively, and $PM_{2.5}$ on haze day and non-haze day were 68.24 and $23.86{\mu}g/m^3$, respectively. Contribution rate of total inorganic water-soluble ion to $PM_{10}$ mass on haze day and non haze day were 58.2% and 61.5%, respectively, and contribution rate of total water-soluble ion to $PM_{2.5}$ mass on haze day and non haze day were 58.7% and 64.7%, respectively. Also, contribution rate of secondary ion to $PM_{10}$ mass on haze day and non haze day were 52.1% and 47.5%, respectively, and contribution rate of secondary ion to $PM_{2.5}$ mass on haze day and non haze day were 54.4% and 53.6%, respectively. AC (anion equivalents)/CE (cation equivalents) ratio of $PM_{10}$ mass on haze day and non haze day were 1.09 and 1.0, respectively, and AC/CE ratios of $PM_{2.5}$ mass on haze day and non haze day were 1.12 and 1.04, respectively. Also, SOR (Sulfur Oxidation Ratio) of $PM_{10}$ mass on haze day and non haze day were 0.32 and 0.17, respectively, and SOR of $PM_{2.5}$ on haze day and non haze day were 0.30 and 0.15, respectively. Lastly, NOR (Nitrogen Oxidation Ratio) of $PM_{10}$ on haze day and non haze day were 0.17 and 0.08, respectively, and NOR of $PM_{2.5}$ on haze day and non haze day were 0.13 and 0.06, respectively.

• 한국환경과학회지
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• 제26권5호
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• pp.591-600
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• 2017

This study was carried out to elucidate the chemical compositions of water-soluble inorganic ions in $PM_{10}$ and $PM_{2.5}$ aerosols collected during summer and winter in downtown Jejusi city. The ratios of $NO_3^-$ to the total mass of ionic species in $PM_{10}$ and $PM_{2.5}$ aerosols largely increase in winter compared to summer, while $SO_4^{2-}$ ratios in both aerosols appear to follow the opposite trend. Moreover, concentrations of $Na^+$, $Mg^{2+}$, $Ca^{2+}$ and $Cl^-$ in $PM_{10}$ and $PM_{2.5-10}$ aerosols are higher in winter than in summer. The nitrate concentrations in $PM_{10}$ and $PM_{2.5}$ aerosols increase with an identical increase in excess ammonium during winter, however, nitrate formation during summer is not important owing to ammonium-poor conditions.