• Title/Summary/Keyword: SA/CA

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Efficiency of Apatite and Limestone in Removing Arsenic from Acid Rock Drainage at the Goro Abandoned Mine (인회석 및 석회석을 이용한 고로폐광산 ARD 내의 비소 저감효율 연구)

  • Park, Myung-Ho;Lee, Young-Woo;Hur, Yon-Kang;Park, Hae-Cheol;Sa, Sung-Oh;Choi, Jung-Chan
    • The Journal of Engineering Geology
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    • v.21 no.3
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    • pp.231-237
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    • 2011
  • An active apatite drainage system has been developed at the Goro abandoned mine, comprising a grit cell, a reaction cell, and a precipitation pond. Leachate from an abandoned adit and tailing ponds is collected in a pipeline and is transported to the apatite drainage system under the influence of the hydraulic gradient. The results of a laboratory experiment performed in 2004 indicate that the reaction cell requires 38.8 ton/year of apatite and that precipitate will have to be removed from the precipitation pond every 3 months. The purpose of this study is to evaluate a laboratory test on the efficiency of limestone and apatite in removing arsenic from ARD (acid rock drainage), and to evaluate the suitability of materials for use as a precipitant for the leachate treatment disposal system. The laboratory tests show that the arsenic removal ratios of limestone and apatite are 67.4%-98.3%, and the arsenic removal ratio of apatite is inversely proportional to its grain size. The arsenic compounds are assumed to be Johnbaumnite and Ca-arsenic hydrate. Therefore, apatite and phosphorous limestone can be used as a precipitant for the removal of arsenic, although it is difficult to remove arsenic from ARD when it occurs in low concentrations.

Neutron Diffraction Study on the Crystal Structure of Yttria-Stabilized Zirconium Oxide (중성자회절법을 이용한 이트리아 저코니아의 결정구조 연구)

  • Jin-Ho Lee;Chang-Hee Lee;Won-Sa Kim
    • Journal of the Mineralogical Society of Korea
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    • v.13 no.3
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    • pp.164-170
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    • 2000
  • Neutron single crystal and powder diffraction techniques have been applied to the structure analysis of yttria-stabilized zirconium, Z $r_{0.73}$ $Y_{0.27}$ $O_{1.87}$., prepared by the skull-melting method. The crystal structure has been determined to be cubic symmetry, space group Fm/equation omitted/ with a=5.155(2)$\AA$, V=136.99(5)$\AA$, Z=4, and R(F)=5.65%, $\omega$R(I)=10.57% for 70 integrated intensities of Bragg Peaks observed from single crystal of Z $r_{0.73}$ $Y_{0.27}$ $O_{1.87}$. The stabilizer atoms randomly occupy the zirconium sites and there are displacements of oxygen atoms with amplitudes of $\Delta$/a~0.033 and 0.11 along <110> and <100> directions from the ideal positions of the fluorite structure, respectively. There are no significant differences in crystallographic data between the single crystal and powder studies. Diffraction pattern after Rietveld refinement, using neutron powder data, has shown the evidence of a tetragonal impurity phase, or a slight tetragonal distortion.

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Adsorption Properties of U, Th, Ce and Eu by Myogi Bentonite Occurring in Japan (일본 묘기광산 벤토나이트의 물리화학적 성질 및 U, Th, Ce 및 Eu 흡착특성)

  • Song Min-Sub;Koh Sang-Mo;Kim Won-Sa
    • Journal of the Mineralogical Society of Korea
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    • v.18 no.3 s.45
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    • pp.183-194
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    • 2005
  • The mineralogical, physicochemical and thermal properties of the Myogi bentonite occurring in Japan were measured. A adsorption properties of U, Th, Ce and Eu ions on the Myogi bentonite were also investigated in different solution concentrations and pH conditions. The Myogi bentonite showed a strong alkaline character (pH 10.4), very high swelling, viscosity property and CEC, and a slow flocculation behavior due to the strong hydrophilic property. By the thermal analysis, the dehydroxylation of crystal water in bulk and clay fractions of the Myogi bentonite occur at $591^{\circ}C$ and $658^{\circ}C$, respectively, The adsorption experiments of ions such as U, Th, Ce and Eu were conducted for 0.2 g bentonites with 20mL solutions of various concentrations and different pH conditions with pH 3, 5, 7, 9, and 11. As a result, the Myogi bentonite showed excellent adsorption capacities for Ce, Th and Eu ions, whereas U ion showed very low adsorption capacity. Generally, Ce, Th and Eu ions showed the similar adsorption properties for the different concentrated solutions and pH conditions. These adsorption properties seem to be affected by the formation of various forms of chemical species and precipitation as well as ionic exchange reaction and surface adsorptions on smectite. Some associated zeolite minerals perhaps have some effects on the adsorption of U, Th, Ce and Eu on Myogi bentonite.

Studies for Component Analysis and Antioxidative Evaluation in Acorn Powders (도토리 가루의 성분분석과 항산화능 평가)

  • Shim, Tae-Heum;Jin, Ying-Shan;Sa, Jae-Hoon;Shin, In-Cheol;Heo, Seong-Il;Wang, Myeong-Hyeon
    • Korean Journal of Food Science and Technology
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    • v.36 no.5
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    • pp.800-803
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    • 2004
  • Chemical components and physiological activities of acorn powders were investigated to develop functional food. Proximate components were 87.29% crude fiber, 1.18% crude fat, 0.84% crude protein, and 0.12% crude ash. Potassium was most predominant mineral, followed by phosphorus, calcium, magnesium, and sodium. Contents of unsaturated fatty acids, such as oleic, linoleic, and linolenic acids, were higher than those of saturated fatty acids. Water and 75% ethanol extracts of acorn powders showed higher absorbency at 285 nm. Water and 75% ethanol extracts exhibited antioxidative activity with $IC_{50}$ of 19.0 and $21.4\;{\mu}g/mL$, respectively, indicating they are the major biological component in acorn powders. Results suggest water extract of acorn can be used as new material for natural antioxidant and functional food.

Hydrologic and Environmental Assessment of an Infiltration Planter for Roof Runoff Use (지붕 빗물이용을 위하여 개발된 침투화분의 환경·수문학적 평가)

  • Moon, So-Yeon;Choi, Ji-Yeon;Hong, Jung-Sun;Yu, Gi-Gyung;Jeon, Je-Chan;Flores, Precious Eureka D.;Kim, Lee-Hyung
    • Journal of Wetlands Research
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    • v.17 no.4
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    • pp.325-331
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    • 2015
  • Due to urbanization and increase in impervious area, changes in natural water circulation system have become a cause of groundwater recharge reduction, streamflow depletion and other hydrological problems. Therefore, this study developed the infiltration planter techniques applied in an LID facility treating roof stormwater runoff such as, performance of small decentralized retention and infiltration through the reproduction of natural water circulation system and use of landscape for cleaning water. Assessment of an infiltration planter was performed through rainfall monitoring to analyze the water balance and pollutant removal efficiency. Hydrologic assessment of an infiltration planter, showed a delay in time of effluent for roof runoff for about 3 hours and on average, 79% of facilities had a runoff reduction through retention and infiltration. Based on the analysis, pollutant removal efficiency generated in the catchment area showed an average of 97% for the particulate matter, 94% for the organic matter and 86-96% and 92-93% for the nutrients and heavy metals were treated, respectively. Comparative results with other LID facilities were made. For this study, facilities compared the SA/CA to high pollutant removal efficiency for the determination to of the effectiveness of the facility when applied in an urban area.

Vimentin Is Involved in Peptidylarginine Deiminase 2-Induced Apoptosis of Activated Jurkat Cells

  • Hsu, Pei-Chen;Liao, Ya-Fan;Lin, Chin-Li;Lin, Wen-Hao;Liu, Guang-Yaw;Hung, Hui-Chih
    • Molecules and Cells
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    • v.37 no.5
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    • pp.426-434
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    • 2014
  • Peptidylarginine deiminase type 2 (PADI2) deiminates (or citrullinates) arginine residues in protein to citrulline residues in a $Ca^{2+}$-dependent manner, and is found in lymphocytes and macrophages. Vimentin is an intermediate filament protein and a well-known substrate of PADI2. Citrullinated vimentin is found in ionomycin-induced macrophage apoptosis. Citrullinated vimentin is the target of anti-Sa antibodies, which are specific to rheumatoid arthritis, and play a critical role in the pathogenesis of the disease. To investigate the role of PADI2 in apoptosis, we generated a Jurkat cell line that overexpressed the PADI2 transgene from a tetracycline-inducible promoter, and used a combination of 12-O-tetradecanoylphorbol-13-acetate and ionomycin to activate Jurkat cells. We found that PADI2 overexpression reduced the cell viability of activated Jurkat cells in1a dose- and time-dependent manner. The PADI2-overexpressed and -activated Jurkat cells presented typical manifestations of apoptosis, and exhibited greater levels of citrullinated proteins, including citrullinated vimentin. Vimentin overexpression rescued a portion of the cells from apoptosis. In conclusion, PADI2 overexpression induces apoptosis in activated Jurkat cells. Vimentin is involved in PADI2-induced apoptosis. Moreover, PADI2-overexpressed Jurkat cells secreted greater levels of vimentin after activation, and expressed more vimentin on their cell surfaces when undergoing apoptosis. Through artificially highlighting PADI2 and vimentin, we demonstrated that PADI2 and vimentin participate in the apoptotic mechanisms of activated T lymphocytes. The secretion and surface expression of vimentin are possible ways of autoantigen presentation to the immune system.

Influence of Air Temperature during the Growing Period on Water Core Occurrence in 'Hongro' Apple Cultivar and the Mitigation Technique (사과 '홍로' 품종의 생육기 기온이 밀증상 발생에 미치는 영향과 경감기술 연구)

  • Park, Moo-Yong;Song, Yang-Yik;Han, Hyun-Hee;SaGong, Dong-Hoon
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.11 no.3
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    • pp.100-110
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    • 2009
  • 'Hongro' is one of the important mid-season apple cultivars bred in Korea. The recent occurrence of water core in Hongro and the consequent problems motivated this study. The objectives of our study were to investigate the influence of air temperature during the growing period on water core occurrence in Hongro and to provide methods to mitigate its impact. Based on our field experiments for three years, the results indicated that the occurrence of water core disorder was due to the prolonged exposure to high temperature ($T_a$) of >$30^{\circ}C$ during the ripening period. The rates of occurrence of water core disorder were higher in the fruit whose weight was more than 300g or those located outside the tree canopy and thus exposed to stronger solar radiation. In terms of mitigating the water core occurrence, the application of spraying $CaCl_2$ four times from late July to August was effective. Furthermore, between 1 and 15 August when the rate of occurrence was high with $T_a$ (from 3:00 to 5:00 p.m.) >$30^{\circ}C$, the micro-water sprinkling for 30 minutes starting at 6:00 p.m. with a supplementary spray conducted two hours after the first application drastically reduced the water core occurrence.

Composition Analysis and Antioxidative Activity from Different Organs of Aster ciliosus Kitamura (부위별 개쑥부쟁이 (Aster ciliosus Kitamura)의 이화학적 성상 및 항산화 활성)

  • Heo, Seong-Il;Jin, Ying-Shan;Sa, Jae-Hoon;Shim, Tae-Heum;Wang, Myeong-Hyeon
    • Korean Journal of Pharmacognosy
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    • v.36 no.3 s.142
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    • pp.164-170
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    • 2005
  • In the present study, we investigated the mineral and metabolite composition and antioxidant activities in the flower, stem and root of Aster ciliosus Kitamura in order to detect biologically active substances and develop novel functional resources. The mineral and metabolite compositions differ significantly among the organ of Aster ciliosus Kitamura. The flower is composed of K as 827 mg/100g. while the stem and root are composed of Na as 654.64mg/100g and 771.70mg/100g, respectively. Contents of unsaturated fatty acids, such as oleic, linoleic, and linolenic acid, were higher than those of saturated fatty acid, such as palmitic acid in flower. The contests of phenolic compounds were measured at 285 nm using different solvents: 2.53 and 2.03 optical density (OD) in chloroform and 1.864 and 1.715 in ethanol extracts for the stem and root, respectively. Antioxidant activity was measured in 75% ethanol extracts: 41.3, 42.0 and $45.2\;{\mu}g/ml$ in stem, root and flower at $IC_{50}$ value, respectively. These results suggest that extracts from Aster ciliosus Kitamura can be potentially used as novel resources for antioxidant and biological active substances.

The Effective for Non-Point pollution Reduction Facility installation project (비점오염저감시설 설치사업의 효과 평가)

  • Choe, Hye-Seon;Geronimo, Franz Kevin;Jeon, Min-Su;Reyes, Nash Jett;Kim, Lee-Hyeong
    • Proceedings of the Korea Water Resources Association Conference
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    • 2020.06a
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    • pp.206-206
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    • 2020
  • 토지이용의 고도화에 따라 비점오염원 부하는 증가하는 추세이며 기후변화에 따른 강우강도 증가 등으로 지표면에 축적된 고농도의 비점오염물질이 하천으로 유출, 수질오염을 가중시키고 있어 비점오염원 관리가 필요하다. 환경부에서 효율적인 비점오염원 관리를 위하여 2004년부터 현재까지 3단계에 걸쳐 비점오염원 관리 종합대책을 수행하고 있으며, 2008년부터 비점국고보조사업을 추진하여 비점오염저감시설 설치를 통한 수질개선 및 수생태계 건강성 확보에 기여하고자 하였다. 이에 본 연구는 비점국고보고사업을 통해 구축된 비점오염저감시설을 대상으로 시설 설치 및 운영 현황과 강우시 비점오염저감 효과 분석을 통한 시설의 평가를 수행하고자 한다. 연구대상시설은 시범시설 및 국고보조시설 총 70개소로 2005~2017년에 준공되었으며, 2016년부터 현재까지 총 4년동안 진행된 모니터링을 바탕으로 연구를 수행하였다. 시설의 용량은 34~97,000㎥의 범위로 SA/CA 1.2~6.6%의 범위이다. 강우시 모니터링은 선행무강우일수 3일이상을 고려하여 수행하였으며 도시지역의 경우 5mm 이상, 농촌지역 10mm 이상시 모니터링을 진행하였다. 시설의 유입과 유출부에서 수질 및 유량 모니터링을 진행하였으며, 수질오염공정시험법에 준하여 BOD, COD, SS, T-N 및 T-P 항목에 대해 분석을 수행하였다. 모니터링 결과, 국내 비점오염저감시설의 평균 부하량은 SS 250.4 kg/day, BOD 89.2 kg/day, COD 136.2 kg/day, TN 51.4 kg/day, TP 7.1 kg/day 로 분석되었으며, 유출부 의 경우 SS 83.8 kg/day, BOD 37.2 kg/day, COD 51.0 kg/day, TN 15.4 kg/day, TP 2.0 kg/day로 나타났다. 또한, 은 오염물질 유입 및 유출 부하량의 상관관계 분석결과 SS, BOD, COD의 유입 및 유출 부하량의 상관성은 높게 나타났으며 특히 유기물질(BOD, COD)의 상관성은 0.8이상으로 분석되었다(p<0.005). 이는 비점오염저감시설에 적용된 식생, 미생물, 여재 등을 통하여 물리학적 및 생태학적 처리를 통해 저감되기 때문으로 판단된다. 하지만, TN은 인위적 요인과 자연적 요인이 복합적으로 작용으로 배출 특성으로 상관성은 매우 낮은 것으로 분석되었다.

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Physico-chemical Characteristics of used Plug Media and its Effect on Growth Response of Tomato and Cucumber Seedlings (재사용 플러그 상토의 이화학적 특성 및 재사용 상토가 토마토와 오이의 묘소질에 미치는 영향)

  • Byun, Hyo-Jeung;Kim, Young Shik;Kang, Ho-Min;Kim, Il Seop
    • Journal of Bio-Environment Control
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    • v.21 no.3
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    • pp.207-212
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    • 2012
  • The objective of the present study is to identify the physico-chemical characteristics of used plug media (UPM) and its effect on growth response of tomato and cucumber seedlings. The UPM from commercial media Mix#5 (Sungro co., Ltd.) was used in this study. This media was sterilized by sterilizer at $120^{\circ}C$ in 30 minutes at 1.5 atm. Physicochemical properties of UPM was compared with new plug media (NPM). Physical properties such as air volume, particle density, solid volume, bulk density were investigated by three phase device (DIK-1130, Japan). And chemical characteristics such as $NO_3$-N, $P_2O_5$, K, Mg, Ca, $SiO_2$, CEC, OM were investigated by soil spectrophotometer (PTIZEN 1412SA, Mecasys Co., Ltd). The result indicates that air volume and water holding capacity of UPM are lower than NPM (25%, 15%, respectively). Bulk density and soil weight are more than two times higher than NPM per unit volume. Compared to NPM, there were no significant different for pH and EC. But CEC of UPM is lower than NPM 40%. In order to compare growth response and ability absorption of inorganic elements by plants, cucumber and tomato seedlings were used and chemical characteristics after growing of mediums were determined. The result indicated that seeding quality of tomato and cucumber in UPM is less than in NPM and almost inorganic ions of UPM are lower than NPM. So it is necessary to improve physicochemical properties of UPM.