• Title/Summary/Keyword: chemical concentrations

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A Study of Concentration Characteristics of Acidic Air Pollutants During the Summer and Winter Seasons in Seoul (서울지역 여름철과 겨울철 산성 오염물질의 농도 특성에 대한 연구)

  • 이학성;강충민;강병욱;김희강
    • Journal of Korean Society for Atmospheric Environment
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    • v.15 no.2
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    • pp.113-120
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    • 1999
  • Winter and summer samples were collected from January 3 to February 7, 1997 and July 26 to September 11, 1997, respectively, in Seoul. This study was to characterize the concentrations of the annular denuder system (ADS) were $HNO_3$, $HNO_2$, $SO_2$ and $NH_3$ in the gas phase, and $PM_{2.5}$ ($d_p$〈2.5$mu extrm{m}$), $SO_4^{2-}$, NO3-, and $NH_4^+$ in the particulate phase. All chemical species monitored from this study showed statistical seasonal variations except for $SO_4^{2-}$ . Nitric acid (HNO3) and ammonia ($NH_3$) exhibited substantially higher concentrations during the summer, while nitrous acid ($HNO_2$) and sulfur dioxide ($SO_2$) concentrations were higher during the winter. $PM_{2.5}$, $NO_3^-$, and $NH_4^+$ were higher leves in the winter. High correlations were found among $PM_{2.5}$, $NO_3^-$ $SO_4^{2-}$ and $NH_4^+$ during two seasons.

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하수처리장 방류수에 용존된 무기화학종의 연속계측자료를 이용한 하천유량, 유속 및 방류량 추적

  • Kim, Gang-Ju;Han, Chan
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2001.04a
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    • pp.3-6
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    • 2001
  • Various Parameters such as stream velocities, discharges, and dispersion coefficients of dissolved solutes were estimated by fitting 1-D nonreactive solute transport model to the time-series chemistry data. This study was done for the reaches of Mankyung River lower than the Jeonju Wastewater Treatment Plant (Jeonju WTP). Korea. Concentrations of inorganic chemicals in the stream waters are strongly influenced by mixing with the chemically distinct effluent from Jeonju WTP. Sulfate, EC. and the total major cation were proved to be nearly conservative in the study area front their relationships with chloride, the conservative chemical species. The solute transport model was constrained to the time-series concentrations for these 4 conservative species. The variations of concentration and discharge of Jeonju WTP were used as input parameters, and the stream velocities, dispersion coefficients, and concentrations and discharges of some inflows were optimized. The differences between the observed arid simulated values for alkalinities and nitrates are inversely correlated and show diurnal fluctuations, indicating the photosynthesis. The parameters obtained front this mode] range from 550 to 774 kcmd (stream discharge at the outlet of the study area), from 0.06 to 0.10 m/sec (flow velocity), and from 0.7 to 6.4 m$^2$/sec (dispersion coefficient). The history of Jeonju WTP discharge was well predicted when optimized, indicating the validity of the model results.

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Antimicrobial Effects Against Food-borne Pathogens of Sanguisorbae Officinalis L. Ethanol Extract (지유 에탄올 추출물의 식품부패균에 대한 항균효과)

  • Choi, Moo Young;Rhim, Tae Jin
    • The Korean Journal of Community Living Science
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    • v.24 no.1
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    • pp.27-36
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    • 2013
  • This study was performed to investigate the antimicrobial effect against food-borne pathogens of Sanguisorbae officinalis L. ethanol extract. The antimicrobial activity of the ethanol extract was determined using a paper disc-diffusion method and the diameter of the clear zone was measured. The diameters of the clear zone in the presence of 10 mg of the ethanol extract were the maximum against Staphylococcus aureus among the tested 4 gram-positive bacteria and Pseudomonas aeruginosa among the tested 7 gram-negative bacteria. Analysis of the minimum inhibition concentrations (MIC) showed that the ethanol extract exhibited a similar efficacy as sorbic acid, well-known chemical preservatives. The growth inhibitory effects of the ethanol extract in the concentrations of 250, 500, 1,000 and 2,000 mg/L on food-borne pathogens were determined against Staphylococcus aureus, Bacillus subtilis, Salmonella Typhimurium and Pseudomonas aeruginosa. The growth of the microorganisms was significantly (p<0.05) inhibited by the ethanol extract in the concentrations higher than 250 mg/L. Thus, the results of the present study demonstrate that the ethanol extract exhibits antimicrobial effects against food-borne pathogens, suggesting that Sanguisorbae officinalis L. could be used as natural antibacterial agent in food.

휴ㆍ폐광산지역 폐재의 중금속 존재형태에 따른 오염순위 설정에 관한 연구.

  • 김휘중;양재의;김동진;박병길;전상호
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2002.09a
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    • pp.75-80
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    • 2002
  • Enormous volumes of mining wastes from the abandoned and closed mines are disposed without a proper treatment at Southeastern part of Kangwon Province. Erosion of these wastes contaminates soil, surface water, and sediments with heavy metals. Objectives of this research were to fractionate heavy metals in the mine waste and to assess the potential S. P. A. G.(Soil Pollution Assesment Guidance) of each metal fraction. Mine wastes analyzed for physical and chemical properties. pH of wastes ranged from 3.3 to 8.0. Contents of total N and loss on ignition matter were in the ranges of 0.2~5.6%, and 0.8~15.3%, respectively. Heavy metals in the wastes were higher in the coal mines than those in the other mine wastes. Total concentrations of metals in the wastes were in the orders of Pb > Zn > Cu > Cd, exceeded the corrective action level of the Soil Environment Conservation Law and higher than the natural abundance levels reported from uncontaminated soils. Relative distribution of heavy metal fractions was residual > organic > reducible > carbonate > adsorbed, reversing the degree of metal bioavailability. Mobile fractions of metals were relatively small compared to the total concentrations. Soil Pollution Assesment Guidance(SPAG) values were ranged from 0.08 to 9.14 based on labile fraction of metal concentrations. SPAG values of labile concentration were lower than those of total concentration.

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Characteristics of Acidic Air Pollutants in Pusan Area Using an Annular Denuder System (Annular Denuder System을 이용한 부산시 대기 중 산성오염물질의 특성)

  • 정장표;정창용;이학성
    • Journal of Korean Society for Atmospheric Environment
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    • v.13 no.5
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    • pp.397-410
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    • 1997
  • An annular denuder filter pack sampling system (ADS) was used to collect acidic air pollutants in Pusan. During the study period (from June 1995 to November 1995), forty eight samples were collected every 12 hours starting from 6:00 in the morning. These samples were devided into two sets of data for day (6:00 a.m.-6:00 p.m.) and night (6:00 p.m.-6:00 a.m.). The chemical species were analyzed for HN $O_3$, HN $O_2$, S $O_2$ and N $H_3$ in the gas Phase, and N $O_3$$^{[-10]}$ , S $O_4$$^{2-}$ and N $H_4$$^{+}$ in the particulate phase. The mean concentrations measured from this study were 0.24, 1.91, 30.07 and 4.24 $\mu\textrm{g}$/㎥ for HN $O_3$, HN $O_2$, S $O_2$ and N $H_3$, respectively. The mean concentrations of N $O_3$$^{[-10]}$ , S $O_4$$^{2-}$ and N $H_4$$^+{\ulcorner}$ were 1.95, 7.36 and 3.48 $\mu\textrm{g}$/㎥, respectively. The mean concentrations of gaseous species except for HN $O_2$ were higher in daytime than in nighttime, but the reverse was true in the particulates except for N $H_4$$^{+}$. +/..

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Characteristics of Acidic Air Pollutants and $PM_{2.5}$ Species in Seoul-Metropolitan Areas Using an ADS (Annular Denuder System을 이용한 수도권지역의 산성오염물질 및 $PM_{2.5}$ 성분농도 특성)

  • 강충민;이승일;조기철;안준영;최민규;김희강
    • Journal of Korean Society for Atmospheric Environment
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    • v.15 no.3
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    • pp.305-315
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    • 1999
  • The annular denuder system(ADS) was used to determine characteristics of acidic air pollutants and $PM_{2.5}$ species in Seoul-metropolitan areas. All measurements were done simultaneously in downtown(Kwanghwamun, Mullae, Chamshil, Ssangmun dongs) and outskirts(Puch n, Kuri cities) during four seasons. The samples were analyzed using ion chromatography for gas-phase matters(HCl, $HNO_2$, $HNO_3$ and $SO^2$) and particulate phase matters($Cl^-$, $NO^{2-}$, $NO_3^-$, $SO_4^{2-}$, $Na^+$, $NH_4^-$ and $Ca^{2+}$) and was measured fine particles($PM_{2.5}$). The seasonal mean concentrations of HCl, HNO2, HNO3 and SO2 in downtown and outskirt areas were very similar. All chemical species monitored from this study showed seasonal variations. Nitric acid(HNO3) and Nitrous acid(HNO2) were showed higher concentrations during the summer. $PM_{2.5}$, $SO_4^{2-}$, $NH_4^-$, $NO_3^-$ and $Cl^-$ in the particulate phase matters were higher levels during the winter months. The concentrations of these components were 54.8, 3.82, 2.49, 1.80 and 1.02$\mu\textrm{g}$/㎥, respectively.

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Natural and Anthropogenic Heavy Metal Deposition to the Snow in King George Island, Antarctic Peninsula

  • Hong, Sung-Min;Lluberas, Albert;Lee, Gang-Woong;Park, Jun-Kun
    • Ocean and Polar Research
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    • v.24 no.3
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    • pp.279-287
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    • 2002
  • Successive 24 snow samples, collected from a 1.2m snow pit at a site on the summit of Main Dome in King George Island, Antarctic Peninsula, were measured for heavy metals such as Pb, Cd, Cu, and Zn and other chemical species. The mean concentrations of heavy metals are 3.48pg/g for Pb, 0.10pg/g for Cd, 16.6 pg/g for Cu and 15.8 pg/g for Zn, respectively. Pb and Cd concentrations observed in our samples are very comparable to those reported for recent snow at other Antarctic sites, while Zn and Cu levels are much higher than those at other sites. The annual fallout fluxes of all heavy metals approximately calculated are, however, much greater in King George Island than at other sites. With respect to the estimates of natural contributions, sea salt spray is found to be a major contributor to Cd and Zn inputs to the snow and minor to Cu inputs. On the other hand, the anthropogenic input can account for a large part of Pb concentrations. A tentative estimate represents that local emissions could be responsible for more than half of the excess Pb flux to the snow in King George Island.

Changes of Chemical Contents in Groundwater at Controlled Horticulture in Honam Area (호남지역의 시설원예재배지 지하수중 화학성분 변동요인 조사)

  • Lee, Deog-Bae;Lee, Kyeong-Bo;Rhee, Kyeong-Su
    • Korean Journal of Environmental Agriculture
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    • v.15 no.3
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    • pp.348-354
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    • 1996
  • This study was carried out to investigate factors influencing on the groundwater quality at controlled horticulture in Honam area in 1995. The deeper groundwater sampling, the lower concentrations of $NH_4-N$ and $NO_3-N$ were observed. There was no difference in concentrations of $SO_4\;^{2-}$ and $Na^+$ in the groundwater below 15m. Contents of $NH_4-N$, $NO_3-N$ and $PO_4\;^{3-}$ in groundwater were the highest at rice transplanting season(the late May) and that of $SO_4\;^{2-}$, $Na^+$ and $Cl^-$ were the highest at dry season(the mid-February). Continuous cultivation of horticultural crops showed higher concentration of $NH_4-N$, $NO_3-N$, $PO_4\;^{3-}$, $Na^+$ and $Cl^-$ in groundwater than rotational culture with rice. The longer cultivation years with horticultural crops, the higher concentrations of $NO_3-N$, $PO_4\;^{3-}$, $SO_4\;^{2-}$ and $Cl^-$ were shown, and constitutional ratio of $NO_3-N$ among the anions increased gradually. Nitrate-N level, exceeded 20mg/l, the critical level for agricultural usage, frequently at Yongjinmyeon Wanju and Janglockdong Kwangju, and $PO_4\;^{3-}$ levels were higher at Seogtandong Iksan than the other places.

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A Study on Physicochemical Characteristics of Achyranthis Radix Extract

  • Choi, Hyun-Suk;Na, Myung-Sun;Lee, Myung-Yul
    • Journal of environmental and Sanitary engineering
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    • v.23 no.1
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    • pp.17-23
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    • 2008
  • Using the ethanol extract, Achyranthis Radix, various chemical characteristics were investigated. The nutritional compositions of the Achyranthis Radix extract were as follows;moisture 42.3%, crude protein 101.1%, crude fat 2.07%, ash 8.94%, and carbohydrate 36.5%. Among the free sugars, the maximum lactose concentration in the Achyranthis Radix extract was obtained at 0.0526 mg% and fructose, maltose, arabinose, and glucose were followed: 0.3654 mg%, 0.1160 mg%, 0.0365 mg% and 0.027 mg%, respectively. The total amino acid concentration of the Achyranthis Radix extract was 8908.3 mg% and concentrations of lysine, aspartic acid, glutamic acid, and arginine were 989.1 mg%, 954.4 mg%, 841.4 mg% and 763.2 mg%, respectively. Among various long chain fatty acids, the maximum concentrations of palmitic acid and linoleic acid were obtained at 47.8% and 31.058%, respectively. However, in the case of organic acid, only the oxalic acid and malic acid were determined. The potassium concentration in the Achyranthis Radix extract was relatively high and the concentrations of Ca, Mg, Fe, Na, Mn, and Zn were as follows: 275.3 mg%, 281.3 mg%, 119.4 mg%, 37.75 mg%, 10.43 mg% and 3.11 mg%, respectively. These results suggest that the Achyranthis Radix extract might have a possible positive effect for medical and edible purposes.

폐광산지역 경작지 토양의 중금속 존재형태와 토양오염평가

  • 김휘중;양재의;전상호
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2003.04a
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    • pp.149-155
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    • 2003
  • Objectives of this research were to fractionate heavy metals in soil samples in the upper Okdong River basin and to assess the potential pollution index of each metal fraction. Soil samples were collected from cultivated land soils and analyzed for physical and chemical properties. pH of cultivated soils ranged from 5.2 to 7.6. Contents of total kelhaldal nitrogen and loss on ignition were in the ranges of 0.6∼2.5%, and 1.9∼12.9%, respectively. Heavy metals in the cultivated land soils were higher in the abandoned closed coal mine near field soils than those in the paddy soils. Total concentrations of metals in the cultivated land soils were in the orders of Zn > Pb > Ni > Cu > Cd, exceed the corrective action level of the Soil Environment Conservation Law and higher than the naturals were abundance levels reported from uncontaminated cultivated land soils. Mobile fractions of metals were relatively small compared to the total concentrations. Soil Pollution Assesment Index(SPAI) values of each fraction of metals were leveled from Non polluted to Moderately polluted based on total concentrations. SPAI values of mobil fractions were lower than those of immobile fractions. Results on metal fractions and SPAI values of the cultivated land soils indicate that field soils samples were contaminated with heavy metals and had potential to cause a detrimental effects on plants. A prompt countermeasure to prevent field soils in the abandoned closed coal mine near fields are urgently needed.

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