• Title/Summary/Keyword: Elemental Carbon

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Exposure Assessments of Environmental Contaminants in Ansim Briquette Fuel Complex, Daegu(III) - Contribution and distribution characteristics of air pollutants according to elemental carbon, crystalline silica, and stable isotope ratio - (대구 안심연료단지 환경오염물질 노출 평가(III) - 원소 탄소, 결정형 실리카 및 안정동위원소비를 이용한 오염원 기여율 및 분포특성 -)

  • Jung, Jong-Hyeon;Phee, Young-Gyu;Shon, Byung-Hyun;Bae, Hye-Jeong;Yang, Won-Ho;Kim, Ji-Young;Kim, Geun-Bae;Choi, Jong-Woo;Park, Sung-Jun;Lee, Kwan;Lim, Hyun-Sul
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.25 no.3
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    • pp.392-404
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    • 2015
  • Objectives: This study measured and analyzed the concentrations of crystalline silica, elemental carbon and the contribution ratio of pollutants which influence environmental and respiratory disease around the Ansim Briquette Fuel Complex in Daegu, Korea. Methods: We analyzed the crystalline silica and elemental carbon in the air according to FTIR(Fourier Transform Infrared Spectroscopy) and NIOSH(National Institute of Occupation Safety and Health) method 5040, respectively. In addition, lead stable isotopes, and carbon and nitrogen stable isotopes were analyzed using MC-ICP/MS(Multi Collector-Inductively Coupled Plasma/Mass Spectrometer), and IRMS(Isotope Ratio Mass Spectrometer), respectively. Results: The concentration of crystalline silica in the direct exposure area around the Ansim Briquette Fuel Complex was found to be $0.0014{\pm}0.0005mg/Sm^3$, but not to exceed the exposure standards of the ACGIH(American Conference of Governmental Industrial Hygienists). In the case of the autumn, the direct exposure area was found to show a level 2.5 times higher than the reference area, and on the whole, the direct exposure area was found to have a level 1.4 times higher than the reference area. The concentration of elemental carbon in the direct exposure area and in the reference area were found to be $0.0014{\pm}0.0006mg/Sm^3$, and $0.0006{\pm}0.0003mg/Sm^3$, respectively. This study confirmed the contribution ratio of coal raw materials to residentially deposited dusts in the area within 500 meters from the Ansim Briquette Fuel Complex and the surrounding area with a stable isotope ratio of 24.0%(0.7-62.7%) on average in the case of carbon and nitrogen, and 33.9%(26.6-54.1%) on average in the case of lead stable isotopes. Conclusions: This study was able to confirm correlations with coal raw materials used by the Ansim Briquette Fuel Complex and the surrounding area. The concentration of some pollutants, crystalline silica, and elemental carbon emitted to the direct-influence area around the Ansim Briquette Fuel Complex were relatively higher than in the reference area. Therefore, we need to impose continuous and substantive reduction countermeasures in the future to prevent particulate matter and coal raw materials in the study area. It is time for the local government and authorities to prepare active administrative methods such as the relocation of Ansim Briquette Fuel Complex.

The Study of PM2.5 and Exhaust Emission Characteristics in the Motorcycles according to Various Lubricants (윤활유 종류에 따른 이륜자동차 PM2.5 및 배출가스 특성 연구)

  • Lim, Yunsung;Lee, Jongtae;Park, Jangmin;Kim, Jeongsoo;Lee, Janghoon
    • Transactions of the Korean Society of Automotive Engineers
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    • v.21 no.4
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    • pp.70-76
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    • 2013
  • Because increased food delivery service and quick delivery service using motorcycle, registration numbers of motorcycles were sharply increased and it could contribute on worsening air quality. In this study, two models(50cc, 125cc) of motorcycle were tested by using three types of engine oil. Two motorcycles were tested with CVS-40 mode for emission characteristics such as CO, THC, NOx, Elemental Carbon(EC), Organic Carbon(OC), sulfate, soot and SOF(soluble organic fraction). Result of according to three types of lubricants which included phosphorus, sulfate ash impacted to particle matters so "C" lubricants is more higher PM than "A", "B" lubricants in this research.

Seasonal Characteristics of Organic Carbon and Elemental Carbon in PM2.5 in Daejeon (대전지역 대기 중 PM2.5의 유기탄소와 원소탄소의 계절별 특성 연구)

  • Kim, Hyosun;Jung, Jinsang;Lee, Jinhong;Lee, Sangil
    • Journal of Korean Society for Atmospheric Environment
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    • v.31 no.1
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    • pp.28-40
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    • 2015
  • To investigate the seasonal variations of carbonaceous aerosol in Daejeon, OC (organic carbon), EC (elemental carbon) and WSOC (water soluble organic carbon) in $PM_{2.5}$ samples collected from March 2012 to February 2013 were analyzed. $PM_{2.5}$ concentrations were estimated by the sum of organic matter ($1.6{\times}OC$), EC, water-soluble ions ($Na^+$, $NH_4{^{+}}$, $K^+$, $Mg^{2+}$, $Ca^{2+}$, $Cl^-$, $SO_4{^{2-}}$, $NO_3{^{-}}$). The estimated $PM_{2.5}$ concentrations were relatively higher in winter ($29.50{\pm}12.04{\mu}g/m^3$) than those in summer ($13.72{\pm}6.92{\mu}g/m^3$). Carbonaceous aerosol ($1.6{\times}OC+EC$) was a significant portion (34~47%) of $PM_{2.5}$ in all season. The seasonally averaged OC and WSOC concentrations were relatively higher in winter ($6.57{\times}3.48{\mu}gC/m^3$ and $4.07{\pm}2.53{\mu}gC/m^3$ respectively), than those in summer ($3.07{\pm}0.8{\mu}gC/m^3$, $1.77{\pm}0.68{\mu}gC/m^3$, respectively). OC was correlated well with WSOC in all season, indicating that they have similar emission sources or formation processes. In summer, both OC and WSOC were weakly correlated with EC and also poorly correlated with a well-known biomass burning tracer, levoglucosan, while WSOC is highly correlated with SOC (secondary organic carbon) and $O_3$. The results suggest that carbonaceous aerosol in summer was highly influenced by secondary formation rather than primary emissions. In contrast, both OC and WSOC in winter were strongly correlated with EC and levoglucosan, indicating that carbonaceous aerosol in winter was closely related to primary source such as biomass burning. The contribution of biomass burning to $PM_{2.5}$ OC and EC, which was estimated using the levoglucosan to OC and EC ratios of potential biomass burning sources, was about $70{\pm}15%$ and $31{\pm}10%$, respectively, in winter. Results from this study clearly show that $PM_{2.5}$ OC has seasonally different chemical characteristics and origins.

Elemental Stoichiometry of Natural Phytoplankton Communities in Reservoirs of the Han River Systems (한강수계 주요 댐호의 식물플랑크톤 군집 세포내 화학양론)

  • Park, Hae-Kyung
    • Journal of Korean Society on Water Environment
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    • v.30 no.6
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    • pp.665-672
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    • 2014
  • Elemental cellular stoichiometry of natural phytoplankton communities was examined in six large dam reservoirs in the Han River system. Carbon (C) and nitrogen (N) contents of the phytoplankton-dominated seston from Lake Soyang was higher than that from other lakes. Phosphorus (P) content showed slight variations among six lakes in the range of $0.04{\sim}0.18{\mu}mol$ P mg $DW^{-1}$. The phosphorus concentrations of lake water showed obvious positive relationship with P and C contents of the phytoplankton-dominated seston. In all six lakes, N:P ratios and C:P ratios in the phytoplankton-dominated seston were more than 23 and 133 respectively, indicating the phytoplankton communities in six lakes have been exposed in phosphorus limited condition. The relative abundance of diatoms showed significant negative correlation with C, N, P contents of the phytoplankton-dominated seston and that of cyanobacteria showed significant positive correlation. Elemental stoichiometry of diatoms-dominated seston showed distinctive less content than that of cyanobacteria-dominated seston. The cellular N:P ratios of diatoms- and cyanobacteria-dominated seston indicate that both main classes of phytoplankton in six lakes are in phosphorus deficiency. Elemental stoichiometry of the phytoplankton-dominated seston in this study could be used for the further ecological stoichiometric studies in six lakes.

Oxidative Stabilization Behaviors of Petroleum-based Isotropic Pitch Fiber Spun by Melt-blown Method

  • Kim, Chan;Lee, Su-Hyun;Kim, Young-Min;Yang, Kap-Seung
    • Carbon letters
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    • v.2 no.3_4
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    • pp.170-175
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    • 2001
  • A petroleum-based isotropic pitch fiber spun by melt-blown method was oxidized in air flow at various conditions. The oxidized pitch fiber obtained was tested for its infusibility and its elemental composition during the process of stabilization. The structural changes were traced by using solvent solubility, FT-IR spectroscopy, and elemental analysis. The samples showed a gradual increase in weight with increasing the oxidization temperature. The weight gain of sample oxidized at $320^{\circ}C$ for 10 min was about 4.5%. The concentration of the pyridine and toluene soluble fraction decreased with an increase in stabilization temperatures. The oxygen uptaken in the stabilization process converted aliphatic side chains into the carbonyl groups. As stabilization proceeded, the more ether and carboxylic acid groups were formed through the oxidations of aldehyde and primary alcohol, and then the carboxylic acid was dehydrated to be aromatic anhydride.

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Characteristics of Total Carbon and Total Organic Carbon Using Elemental Analyzer in Hyung-Do Intertidal Zone Sediments (원소분석기를 이용한 형도 퇴적물의 총탄소 및 총유기탄소 특성)

  • Lee, Jun-Ho;Park, Kap-Song;Woo, Han-Jun
    • Economic and Environmental Geology
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    • v.45 no.6
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    • pp.673-684
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    • 2012
  • Quantitative understanding of total carbon, total inorganic carbon and total organic carbon contained in ocean sediments is a basic data for interpretation of oceanic sediment environments. Elemental analyzer(EA) is frequently used for the analysis of carbon contents in inland soils and ocean sediments. Carbon and nitrogen contents of the soil reference material analyzed by an EA were 2.30% and 0.21% with standard deviations of 0.02 and 0.01, respectively. Relative standard deviations were 0.01 and 0.06, respectively, representing a high precision. Regression analysis of TOC and TC analysis results for the samples with TOC of less than 2.0% for the site in Hyung-Do showed a linear relationship with a slope of 0.9743($R^2$=0.9989, n=38), and the results of a relationship regression analysis between total organic carbon contents less than 0.5% and average grain size except for two samples showed a linear relationship with a slope of 0.0444($R^2$=0.6937 n=36). TOC contents of surface sediments were in the ranges of 0.10~1.67%(Average $0.26{\pm}0.37%$) with TOC values of 1.67% at S02 sampling site, 1.13% at S07 sampling site, and less than 1.00% at remaining sites. In the case of PC 01 core sediments, TOC showed the highest value of 0.20% near 70 cm. In the case of PC 02 core sediments, the highest value of 0.24% was indicated near 60 cm. The analysis method of organic carbon obtained from Hyung-Do Intertidal zone sediment sample results may be considered applicable to an organic carbon analysis for ocean sediments and useful for organic carbon analysis experiments of ocean sediments with a reduction in time required for the analysis and a high precision coupled with a high accuracy.