• 대기
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• 제25권1호
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• pp.185-191
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• 2015

고산기후관측소에서 2008년 8월과 9월의 Cheju ABC Plume Monsoon Experiment (CAPMEX) 기간 동안 3파장 photoacoustic soot spectrometer (PASS)로 측정된 에어로졸 흡수계수(${\sigma}_a$)와 에어로졸 산란계수(${\sigma}_s$)를 기존의 연구에서 널리 사용되고 있는 aethalometer 및 nephelometer의 동시관측 결과와 비교하였다. PASS ${\sigma}_a$의 관측결과는 aethalometer ${\sigma}_a$와 시간 변화 경향성이 매우 잘 일치했으나, 532 nm의 경우 절대값 면에서 PASS ${\sigma}_a$가 약 53% 큰 값을 보여 다소 차이가 있음을 알 수 있었다. PASS ${\sigma}_s$의 관측결과는 nephelometer ${\sigma}_s$와 비교했을 때, 근소한 차이로 매우 잘 일치함을 확인하였다(Bias Difference: $13.6Mm^{-1}$). 대기 중의 상대습도(RH)가 증가함에 따라 ${\sigma}_a$보다는 ${\sigma}_s$에 대한 영향이 큰 것으로 사료된다. Nephelometer ${\sigma}_s$와 PASS ${\sigma}_s$의 비율은 상대습도가 증가할수록 명확히 증가하는 경향성을 보였다. 이는 RH가 증가함에 따라서 PASS의 ${\sigma}_s$가 nephelometer ${\sigma}_s$에 비해서 상대적으로 감소하였음을 의미하며, 이러한 경향성은 RH가 70~80%를 넘어서면서 차이가 더욱 두드러지게 나타났다. Nephelometer와 aethalometer의 ${\sigma}_a$ 및 ${\sigma}_s$ 관측 결과 보다 PASS의 측정 결과로부터 산출한 $A{\AA}E$와 $S{\AA}E$가 더 크게 나타났다.

• 대기
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• 제18권4호
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• pp.459-474
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• 2008

Aerosol scattering coefficients for three different wavelengths ($\lambda$=450,550,700 nm) are measured almost continuously by a nephelometer in Seoul for a period of 13 months (February 2007-February 2008), which includes two weeks break in August 2007 for measurements at Daegwallyeong and YoungJongdo. The mean of the daily average scattering coefficients at $\lambda$=550 nm is $194.1{\pm}144.2Mm^{-1}$ and the minimum and maximum are $14.3Mm^{-1}$ and $998.1Mm^{-1}$, respectively. The scattering coefficient shows a general increasing trend with atmospheric relative humidity (RH). When the data are classified according to weather conditions, the days with no major weather events show the smallest scattering coefficient and also the lowest RH. Surprisingly haze/fog days show the largest scattering coefficient and Asian dust days comes in second. Although the variation is large within a season, winter shows the largest and autumn shows the smallest scattering coefficient. The average ${\AA}ngstr{\ddot{o}}m$ exponent is $1.40{\pm}0.32$ for the entire Seoul measurement. As expected, Asian dust days show the smallest ${\AA}ngstr{\ddot{o}}m$ exponent and haze/fog days are the next, suggesting more efficient hygroscopic growth of aerosols for this weather condition. Aerosol scattering coefficient seems to show better correspondence with CCN concentration rather than total aerosol concentration, which may indicate that CCN active aerosols are also good scattering aerosols.

• 한국입자에어로졸학회지
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• 제11권1호
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• pp.1-8
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• 2015

In this study, indoor $PM_{10}$ concentration was measured by different type of real-time instruments in public transport vehicles. Light-scattering method is widely used in measuring the size of particulate matters and there is two types of light-scattering methods; one is the nephelometer type which measures the light-scattering degree by aerosol cloud, the other is the spectrometer type which measures light-scattering degree by individual particle. We observed the variation of $PM_{10}$ in KTX, subway and express bus carriages by 1-minute resolution and found that there is similar tendency in pattern among 4 light-scattering devices but difference in absolute concentrations. By comparing gravimetric result in a subway cabin, the spectrometer type device, C, was chosen as a reference device. The conversion factors of nephelometer device A-1, A-2, and B were 1.666, 1.463 and 2.125 respectively.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2000년도 추계학술대회 논문집
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• pp.57-58
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• 2000

대기 중에 분포되어 있는 다양한 크기와 종류의 에어로졸은 산업의 발전과 급속한 인구의 증가로 인해 가중되고 있으며, 특히 이로 인해 도심지역의 시정감쇄에 큰 영향을 미치고 있다. 특히 도시지역의 대기 중 미세 입자(PM2.5)의 시정감쇄에 대한 영향은 거대입자에 비하여 지배적인 것으로 나타난다. 그 과정에서 대기중 입자의 광학적인 성질 뿐 만 아니라 기상적인 변동 특히 온도와 습도에 의한 시정의 변화는 큰 영향을 받고 있다. (중략)

• 한국대기환경학회지
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• 제31권4호
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• pp.319-329
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• 2015

The characteristics of aerosol light extinction were investigated by comparing measured and calculated extinction coefficient to understand the contribution of air pollutants on visibility impairment for data during 4 months (Jan~ April), 2014. The integrated nephelometer and aethalometer system were installed to measure the scattering and absorption coefficients of aerosol as well as BAM 1020, MARGA, semi-continuous OCEC analyzer, and online-XRF to calculate the extinction coefficient. The IMPROVE_2005 equation was used to determine the contributions of different chemical components on visibility impairment in $PM_{2.5}$ and $PM_{10}$ due to highest correlation with measured data. Sulfate, nitrate, and organic mass by carbon (OMC) of fine aerosol were the major contributors affecting on visibility impairment. Total contributions to light extinction were calculated as $631.0Mm^{-1}$ for the worst-case and $64.4Mm^{-1}$ for the best-case. The concentrations of aerosol component for the worst-case were 38.4 times and 45.5 times larger than those of the best-case for $(NH_4)_2SO_4$ and $NH_4NO_3$, respectively. At lower visibility condition, in which extinction coefficient was higher than $400Mm^{-1}$, extinction coefficient varied according to the relative humidity variation regardless of $PM_{2.5}$.

• Tuberculosis and Respiratory Diseases
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• 제50권5호
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• pp.615-623
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• 2001

Background : Pneumoconiosis is a parenchymal lung disease that results from the accumulation of coal dust in the lungs and the consequent tissue reaction. To evaluate the role of various personal factors in pneumoconiosis and the significance of some serologic markers for assessing the disease activity related to pneumoconiosis, the Rheumatoid Factor(RF), ${\alpha}_1$-AT, C-Reactive Protein(CRP), ceruloplasmin and fibrinogen levels were measured. Method : All the patients were males, 45-76 years old, and the mean duration of coal dust exposure was 23.2 years. 51 patients were classified as having Simple Pneumoconiosis (SP), 59 had Progressive Massive Fibrosis (PMF). Fifty eight men with ages ranging from 26-70 years were used as normal controls. The serum RF and CRP were titrated using an Autochemistry analyzer (HITACHI 7150 : Japan) and the ${\alpha}_1$-AT and ceruloplasmin levels were measured using a Nephelometer (Behring Nephelometer : Germany) and the fibrinogen levels were estimated by using an Autoanalyzer for hematologic coagulation. Result : There was a higher RF level in the SP, and PMF groups than in the control groups but there was no statistical difference. The CRP, ${\alpha}_1$-AT, and ceruloplasmin levels were also higher in the SP, and PMF groups. However, the fibrinogen concentration was within the normal ranges in both the SP and PMF groups. Conclusion : The CWP (Ed note : Define CWP) patients had significantly higher CRP, ${\alpha}_1$-AT, and ceruloplasmin levels compared to the control group. It is believed that these serologic changes could be used as a marker of the disease activity.

• Tuberculosis and Respiratory Diseases
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• 제46권2호
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• pp.165-174
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• 1999

연구배경: CWP은 주로 석탄 분진을 흡입함으로써 발생하는 폐 실질의 병변으로 단순 흉부 방사선 소견상 폐 결절의 기준을 1cm로 하여 SP과 PMF으로 구분한다. PMF의 경우 환기 능력의 장애가 심하고 조기사망율이 증가하고 있으나 모든 광부에서 PMF이 발생하는 것은 아니여서 이러한 CWP의 발생에 관여하는 요인을 찾기 위한 많은 연구가 있어왔다. 본 연구의 주목적은 진폐증 환자에서 질환의 심한 정도를 ILO 분류에 따라 SP, PMF으로 구분한 후 감염이나 기타 기저 질환이 없는 상태에서의 혈중 면역 글로블린 농도를 흡연력과 연령에 의한 면역 글로불린의 변화를 고려한 후 진폐증의 심한 정도와 혈청면역 글로불린 농도와의 연관성을 관찰하기 위하여 시행하였다. 방 법: 태백 중앙 병원과 영동 병원의 진폐증 환자중 정밀 검사를 시행하기 위해 병원을 내원한 SP 환자 51명과 입원중이거나 정밀검사를 시행한 PMF 환자 59명을 대상으로 하였고 대조군은 진폐증 환자와 나이, 성별 및 흡연 병력이 적합하면서 진폐에 노출된 병력이 전혀 없는 주변 아파트 경비원과 병원내 지원자 58명을 대상으로 하였다. 면역 글로불린의 검사(IgA, IgG, IgM)는 독일 Behring사에서 제조한 각 각의 Kit를 사용하여 Nephelometer 분석기(Behring Nephelometer : Germany)를 사용하여 측정하여 대조군 57명, SP 51명, PMF 49명의 면역 글로불린을 측정하였다. 결 과: 본 연구에서 대조군의 나이에 따른 혈청 면역 글로불린의 변화는 나이가 증가 할수록 IgG는 의의 있게 증가 하였고 흡연력에 의한 면역 글로불린의 차이는 없었다. 대조군, SP, PMF사이의 혈중 면역 글로불린의 농도간에는 차이가 없었으나 흡연력과 나이의 영향을 고려한 다중회귀 분석에서 IgG의 농도는 대조군과 비교하여 SP 환자군에서 통계학적으로 의미 있게 감소하였고 PMF환자군에서는 감소하는 경향이 있었다. 폐기능 검사의 중증도와 면역 글로불린 농도사이에는 관련이 없었다. 결 론: 흡연력과 연령을 고려한 상태에서 진폐증 환자의 혈청 면역 글로불린의 농도는 대조군과 비교하여 SP 환자군에서 IgG의 농도가 감소하였으며 PMF 환자군에서도 감소하는 경향을 나타내어 진폐증과 IgG사이에 연관성이 있다고 생각되며 폐기능 검사의 중증도와 면역 글로불린과는 관련이 없다고 생각된다. 향후에 CWP의 발생 및 진행 기전을 이해하기 위해서 많은 수의 진폐증 환자를 대상으로 하는 전향적 연구와 함께 염증세포 및 싸이토카인의 역할에 대한 연구가 필요할 것으로 생각된다.

• 한국대기환경학회지
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• 제11권3호
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• pp.291-298
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• 1995

An intensive field study was carried out during Aug. 1993 in Seoul to study the characteristics of summertime visibility and diurnal trend of ionic composition of ambient particles. A transmissometer, nephelometer with heated and unheated inlets, PM3 fine particle sampler, and cascade impactor were used to measure optical and particle properties of ambient air. During this study period, a weak smog episode has occurred. Light scattering by particles is the most dominant factor on total light extinction. The effect of light absorption by particles in Seoul is much higher than other major cities in U.S.A. throughout the summer and fall with relatively constant values. The effect of water on $b_{sp}$ was small during the period. The particle size distribution shows a typical bimodal one. Sulfate, ammonium, chloride, and nitrate are the major chemical species in fine fraction aerosols, about 30% of toral mass concentration. Concentraion of sulfate is higher during the daytime while those of nitrate and chloride are higher during the nighttime. Ammonium concentration is constant through the daytime.

• 한국대기환경학회지
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• 제10권2호
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• pp.137-145
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• 1994

A visibility analysis model based on the Mie theory is applied to the measurements during the fall, 1993 in Seoul. Model estimations of the total extinction coefficient $b_{ext}$, and the particle scattering coefficient, $b_{sp}$ are in good agreement with the measured values by a transmissometer and a nephelometer, respectively. These values show strong dependency on the mass loading of fine particles( $D_{p}$ ＜3.0${\mu}{\textrm}{m}$) but show no apparent relation with that of coarse particles(3.0${\mu}{\textrm}{m}$＜ $D^{p}$ ＜10${\mu}{\textrm}{m}$). Relative humidity plays an important role in determining the size of particles which in turn, affects the optical efficiency of aerosol. Based on the composition analysis with cut size nitrate concentration is higher than the sulfate concentration in PM3-10 but they are comparable to each other in PM3. Considering in 1985, it demonstrates a drastic increase of nitrate concentration between 1985 and 1993. It is found that measured and estimated light extinction budget were in good agreement within 10% and that scattering by particles is responsible for about 50-55% and 70-80 % of total extinction during clear and smoggy periods respectively.y.

• 한국입자에어로졸학회지
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• 제6권2호
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• pp.91-103
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• 2010

Size-segregated number concentration and scattering coefficient of urban aerosols were measured using an SMPS (scanning mobility particle sizer) and a nephelometer, respectively in Seoul, Korea, during the winter season of 2003. The average number concentrations of ultrafine particles (20~100 nm) and accumulation mode particles (100~600 nm) were $2,170\;particles\;cm^{-3}$ and $1,521\;particles\;cm^{-3}$, respectively. The scattering coefficient at the wavelength of 550 nm ranged from $62.6Mm^{-1}$ to $330.1Mm^{-1}$ and average value was $163.4Mm^{-1}$. The peak concentrations of ultrafine particles and accumulation mode particles were simultaneously recorded between 6:00 and 9:00 A.M., indicating the effect of vehicle emissions which are major air pollution sources in the urban atmosphere. On average, the number concentration of ultrafine particles was 1.4 times higher than that of accumulation mode particles, although it was a little higher during the morning peak time. The variation of aerosol scattering coefficient was in good agreement with that of accumulation mode particle number concentration rather than that of ultrafine particle number concentration.g coefficient was in good agreement with that of accumulation mode particle number concentration rather than that of ultrafine particle number concentration.