• 환경위생공학
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• 제17권2호
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• pp.11-17
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• 2002

Diesel particulate matter (DPM) is known to be one of the major harmful emissions produced by diesel engines. The majority of diesel particles are in the range of smaller than $I{\mu}\textrm{m}$. Because of their tiny volume, ultrafine diesel particles contribute very little to the total mass concentration which is currently regulated for automobile emissions. Diesel particles are known to have deleterious effects upon human health because they penetrate human respiratory tract and have negative effects on the health. The measurement of the number distribution of nanometer size particles (nanoparticles) in the diesel exhaust emission is important in order to evaluate their environmental and health impact, and to develop new types of diesel particulate filters. In this study, we directly sampled particulate matters emitted from a diesel truck mounted on the chassis dynamometer by a flow separator and dilution system, and measured the nanoparticles using two types of differential mobility analyzers combined with a Faraday cup electrometer (FCE) and a condensation particle counter (CPC). The particle size distributions were analyzed by changing engine operation condition, i.e. ratio of engine loading. The total number concentration of particles were increased with the engine loading ratio and the nanoparticles (less than 50nm) were affected by hydrocarbon (HC) concentration in the diesel exhaust.

• Asian Journal of Atmospheric Environment
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• 제6권4호
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• pp.246-258
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• 2012

Particulate matter deposited on leaf surfaces may cause erosion/abrasion of epicuticular wax and the malfunction of stomata. However, the deposition processes of particulate matter, such as elemental carbon (EC), has not been studied sufficiently in Asian forest ecosystems. Deposition processes for particulate ${SO_4}^{2-}$ and EC were studied in a Japanese cedar forest in Kajikawa, Niigata Prefecture, Japan, and in a dry evergreen forest and a dry deciduous forest in Sakaerat, Nakhon Ratchasima province, Thailand. The ${SO_4}^{2-}$ fluxes attributed to rainfall outside the forest canopy (RF), throughfall (TF), and stemflow (SF) showed distinct seasonalities at both sites, increasing from November to February at the Kajikawa site and in March/April at the Sakaerat site. Seasonal west/northwest winds in winter may transport sulfur compounds across the Sea of Japan to the Kajikawa site. At the Sakaerat site, pollutants suspended in the air or dry deposits from the dry season might have been washed away by the first precipitations of the wet season. The EC fluxes from RF and TF showed similar variations by season at the Kajikawa site, while the flux from TF was frequently lower than that from RF at the Sakaerat site. Particulate matter strongly adsorbed onto leaf surfaces is not washed away by rainfall and contributes to the EC flux. At the Kajikawa site, Japanese cedar leaf surfaces accumulated the highest levels of particulate matter and could not be neglected when calculating the total flux. When such leaf-surface particles were considered, the contribution of dry deposition to the total EC flux was estimated to be 67%, 77%, and 82% at the Kajikawa site, and at the evergreen and deciduous forests of the Sakaerat site, respectively. Leaf-surface particles must be included when evaluating the dry and total fluxes of particulate matter, in particular for water-insoluble constituents such as EC.

• 한국대기환경학회지
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• 제30권3호
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• pp.261-269
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• 2014

This study focused on the performance of the newly developed hybrid filter system to capture fine particulate matter and mercury compounds in a coal-fired power plant. The hybrid filter system combining bag-filter and electrostatic precipitator had been developed to remove fine particulate matter. However, it would have a good performance to control mercury compounds as well. In Hybrid filter capture system, the total removal efficiency of total mercury compounds consisting of particulate mercury ($Hg_p$), oxidized mercury ($Hg^{2+}$), and elemental mercury ($Hg^0$) was 66.2%. The speciation of mercury compounds at inlet and outlet of Hybrid filter capture system were 1.3% and 0% of $Hg_p$, 85.2% and 68.1% of $Hg^0$, and 13.5% and 31.9% of $Hg^{2+}$, respectively. In hybrid filter capture system injected with 100% of flue-gas, the removal efficiency of total mercury was calculated to increase to 93.5%.

• 한국환경과학회지
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• 제18권1호
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• pp.41-47
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• 2009

In building demolition work, major dust-generating activities are blasting concrete and rock. The aim of this study was to find the characteristic of particle size of dusts which were generated during building demolition work using explosion. The DustMate of the Turnkey-Instruments Ltd. was used for particulate size-selective sampling of the four sites. TSP(Total Suspended Particle), PM10(Particle Matter $10{\mu}m$), PM2.5(Particle Matter $2.5{\mu}m$), and PM1.0(Particle Matter $1.0{\mu}m$) were measured during building demolition work using explosion. The large particulate (higher than the diameter $10{\mu}m$) showed to be higher than 50%. The particulate ranged from $10{\mu}m\;to\;2.5{\mu}m$ showed about 30-40%. PM2.5 was not scarcely detected in the samples collected for building demolition work using explosion. We conclude that the dust generated during building demolition work using explosion has not most respirable particulate.

• 한국환경보건학회지
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• 제26권4호
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• pp.1-8
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• 2000

The objective of this study was to identify the sources and to estimate the source contributions to the atmospheric TSP(total suspended particulate matter) and PM-10(particulate matter with aerodynamic diameters less than 10$\mu\textrm{m}$) concentration in Taegu area. A total of 84 samples was collected during the January to December 1999. TSP and PM-10 were collected on filters by portable air sampler, and heavy metals in TSP and PM-배 were analyzed by ICO(Inductively Coupled Plasma Spectrometery) after preliminary treatment. The results were follow as : First, annual average of TSP and PM-10 concentration was 123 and 69$\mu\textrm{g}$/㎥ respectively. The concentration of TSP and PM-10 were highest in winter season compared to other seasons. Second, the concentration of Al, Fe, Mn were higher in TSP than in PM-10, indicating that these heavy metals are generally associate with natural contributions. Third, metal combinations showed that a high correlation among concentrations of heavy metals were follows: As Al, Fe and Mn in TSP ; Ni, Cr, Cd and Pb in PM-10. Finally, Statistical analysis was performed using Principal Components Analysis(PCA) in order to find possible sources of the pollutants. The factor analysis was permitted to identify four major sources(soil/road dust resuspension, waste incineration, furl combustion, vehicular emission) in each fraction. These source accounted for at least 83, 85% of variance of TSP and PM-10 concentration in Taegu area.

• Journal of Preventive Medicine and Public Health
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• 제16권1호
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• pp.67-77
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• 1983

To investigate the an air pollution by particulate matter and its dispersion, a cement plant produceing portland cement 600,000 ton/year and its vicinity were surveyed from Obtober, 1980 to April, 1983. The survey was mainly focused on main stack emmission rate of the cement plant and particle size distribution in the dust, dustfall and total suspended particulate concentration in the area by month and distance from the stack. The results of the study were as follows; 1. The main stack emission rate was surveyed before and after the spray tower was additionally installed to the original E.P bag filter. Before the spray tower installed, the main stack emission rate was higher ($0.64g/Nm^3$) than the emission standard of Korean Environmental Preservation Law's ($0.59g/Nm^3$, amended to $0.4g/Nm^3$ on April 1983), but after the spray tower was installed, its main stack emission rate was markedly decreased to the standard ($0.43g/Nm^3$). 2. $2{\sim}3{\mu}m$ of the particle size was the largest portion (20.8%) of the dust particulate from the main stack and 50% of the frequency distribution was $1.5{\mu}m$ of the size. Most particle size was below $10{\mu}m$. 3. The spray tower reduced the dustfall to $37.81{\sim}9.76\;ton/km^2/month$ while dustfall appeared at $45.29-15.45ton/km^2/month$, in the vicinity of plant before spray tower installed 4. Mean concentrations of total suspended particulate for 24 hours of the various stations were determined in $20.6-200.0{\mu}g/m^3$, 3 stations of tham were higher than the value of Harry and William's arthmetic average standard $130{\mu}g/m^3$. 5. Linear regression between dustfall [X] and total suspended particulate[Y] concentration was an equation, Y=4.024X+11.479.[r=0.91] 6. During the whole seasons in the opposite area 100m apart from the omission source the prevailing wind direction was with estimated more than $30ton/km^2/month$, and the concentration of total suspended particulate for 24 hours averaging time was more than $140{\mu}g/m^3$ in the same area and direction. 7. Assuming the wind direction were constant through the day dustfalls for a day were estimated at $13.40ton/km^2/day,\;10.79ton/km^2/day$ and $4.55ton/km^2/day$ at various distances of 100m, 500m and 1,500m from the emission source respectively. 8. In the simutalion of dustfall and suspended dust by area, Gaussian dispersion model modified by size distribution of particulate matter was not applicated since the emission of dust were from multi sources other them stack. From the above results, it could be applied that the dispersion of dust from the cement plant is estimated and regulated for the purpose of environmental protection.

• 자원환경지질
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• 제55권6호
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• pp.701-716
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• 2022

This study investigated the distribution behaviors of PM2.5 and PM10 at two air quality monitoring sites, Go-eup (GO) and Backseokeup (BS), located in Yangju City, South Korea. The amounts of emissions sources of pollutants were analyzed based on the Clean Air Policy Support System (CAPSS), and the contribution rates of neighboring cities were enumerated in Yangju. Yangju has a geological basin structure, and it is a city with mixed urban and rural characteristics. The emission concentration of particulate matter was affected by geological and seasonal factors for all sites observed in this study. Therefore, these factors should be considered when establishing policies related to particulate matter. Because the official GO and BS station sites in Yangju are both situated in the southern part of the city, the representativeness of both stations was checked using correlation analysis for the measurement of PM2.5 and PM10 by considering two more sites-those of Bongyang-dong (BY) and the Gumjun (GJ) industrial complex. The data included discharge amounts for business types 4 and 5, which were not sufficiently considered in the CAPSS estimates. Because the 4 and 5 types of businesses represent over 92.6% of businesses in this city, they are workplaces in Yangju that have a significant effect on the total air pollutant emission. These types of businesses should be re-inspected as the main discharge sources in industry, and basic data accumulation should be carried out. Moreover, to manage the emission of particulate matter, attainable countermeasures for the main sources of these emissions should be prepared in a prioritized fashion; such countermeasures include prohibition of backyard burning, supervision of charcoal kilns, and management of livestock excretions and fugitive dust in construction sites and on roads. The contribution rates by neighboring cities was enumerated between 6.3% and 10.9% for PM2.5. Cooperation policies are thought to be required with neighboring cites to reduce particulate matter.

• Annals of Occupational and Environmental Medicine
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• 제35권
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• pp.51.1-51.15
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• 2023

Background: Recently, there has been increasing worldwide concern about outdoor air pollution, especially particulate matter (PM), which has been extensively researched for its harmful effects on the respiratory system. However, sufficient research on its effects on cardiovascular diseases, such as hypertension, remains lacking. In this study, we examine the associations between PM levels and hypertension and hypothesize that higher PM concentrations are associated with elevated blood pressure. Methods: A total of 133,935 adults aged ≥ 40 years who participated in the Korean Genome and Epidemiology Study were analyzed. Multiple linear regression analyses were conducted to investigate the short- (1-14 days), medium- (1 and 3 months), and long-term (1 and 2 years) impacts of PM on blood pressure. Logistic regression analyses were conducted to evaluate the medium- and long-term effects of PM on blood pressure elevation after adjusting for sex, age, body mass index, health-related lifestyle behaviors, and geographic areas. Results: Using multiple linear regression analyses, both crude and adjusted models generated positive estimates, indicating an association with increased blood pressure, with all results being statistically significant, with the exception of PM levels over the long-term period (1 and 2 years) in non-hypertensive participants. In the logistic regression analyses on non-hypertensive participants, moderate PM₁₀ (particulate matter with diameters < 10 ㎛) and PM_2.5 (particulate matter with diameters < 2.5 ㎛) levels over the long-term period and all high PM₁₀ and PM_2.5 levels were statistically significant after adjusting for various covariates. Notably, high PM_2.5 levels of the 1 year exhibited the highest odds ratio of 1.23 (95% confidence interval: 1.19-1.28) after adjustment. Conclusions: These findings suggest that both short- and long-term exposure to PM is associated with blood pressure elevation.

• 한국환경과학회지
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• 제23권7호
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• pp.1375-1383
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• 2014

Total organic carbon(TOC), Total nitrogen(TN), and carbon and nitrogen stable isotopes were measured in the sediment and suspended parties in fresh lake water and saline estuarine water to determine the sources of Particulate organic matter(POM) in the sediments of the Youngsan river estuary. POM in the freshwater discharge water was mostly phytoplankton origin with little trace of terrestrial plants. POM from phytoplankton blooms formed in estuarine water in response to the nutrient enriched freshwater discharges was the most important sources of POM in the sediment near the dike, comprising more than 40% of the total organic matter. POM from freshwater phytoplankton and oceanic phytoplankton were also important sources of the sediment POM, and their contributions varied with the distances from the dike. Contribution of freshwater phytoplankton to sediment POM decreased from the dike to the outside of the estuary.

• 농촌의학ㆍ지역보건
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• 제46권1호
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• pp.1-11
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• 2021

이 연구의 목적은 천식과 만성폐쇄성폐질환 환자들의 미세먼지에 대한 인식, 지식, 예방행위 수준과, 예방행위에 영향을 미치는 요인을 확인하기 위한 것이다. 이 연구는 서술적 조사연구로 연구대상은 대구광역시 소재 일개 대학병원 호흡기전문질환센터를 방문한 만 19세 이상, 만 80세 이하의 만성호흡기질환자를 편의표본추출하였고, 2019년 12월부터 2020년 1월까지 구조화된 자기기입식 설문조사로 자료를 수집하여, 총 212부의 자료를 분석 대상으로 하였다. 연구대상자는 212명이었으며, 이중 천식 112명(52.8%), 만성폐쇄성폐질환 100명(47.2%)이었다. 미세먼지에 대한 인식, 지식, 예방행위의 평균 점수(10점 만점)는 천식 환자는 각각 7.92점, 6.99점, 7.10점이었고, 만성폐쇄성폐질환자는 각각 7.72점, 6.24점, 6.80점 이었다.미세먼지 지식 점수는 천식환자가 만성폐쇄성폐질환자보다 유의하게 높았다(p=0.007). 미세먼지 예방행위 수준에 영향을 미치는 요인은 천식은 인식 점수, 지식 점수, 연령이며, 만성폐쇄성폐질환은 인식 점수가 유의한 요인이었다. 이상의 결과 천식과 만성폐쇄성폐질환 환자의 예방행위에 영향을 주는 요인은 천식은 인식 점수, 지식 점수, 연령이며, 만성폐쇄성폐질환은 인식점수였다. 미세먼지 예방행위 수준을 높이는 것은 미세먼지로 인한 만성호흡기질환의 악화를 막을 수 있으므로, 질환에 따른 대상자의 특성을 고려한 중재 프로그램의 개발과 지속적이고 반복적인 교육이 요구된다.