• 제목/요약/키워드: Acid-rain

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Effect of Acid Deposition on the Acidification of Surface Water II : Column and the Field Studies (산성강하물이 지표수의 산성화에 미치는 영향 II: 컬럼연구 및 현장조사)

  • 김영관;우경식
    • Journal of Korea Soil Environment Society
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    • v.2 no.1
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    • pp.35-44
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    • 1997
  • A column study using artificial acid rain was conducted to evaluate the buffering capacities in soil layer and host rock. In an effort to compare the effect of composition of host root two valleys of which compositions of host rock are different were chosen within the study area and the pHs of the water flowing in the valleys were measured from May, 1996 to October, 1996. The pHs of the artificial acid rain prepared by adding appropriate amounts of both sulfuric and nitric acids to distilled water were 3, 4, and 5, and the column effluents were analyzed for major cations and anions. The cation exchange capacities(CECs) of A Horizon and the B Horizon were 9.68 and 6.16 meq/100g, respectively, Compared to the B Horizon, the pH in the column effluent of A Horizon with larger CEC was higher. The sums of $Ca^{2+}$, $Mg^{2+}$, $Na^{+}$in the column effluents gradually decreased, indicating the loss of CEC by acid rain. The field study showed that pHs of the surface water in the valleys increased as the water flows downwards. The magnitude of this buffering capacity was greater for the valley in which smectite in addition to kaolinite and illite was a weathered product of host rocks. This also indicates that host rock as well as soil layer retains the buffering capacity.

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Ionic Composition of Early and Succeeding Rainwater in Pusan Area (부산시 일부지역에 대한 초기 및 후속강우의 이온성분 특성)

  • 최금찬;김찬환
    • Journal of Korean Society for Atmospheric Environment
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    • v.14 no.4
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    • pp.361-368
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    • 1998
  • Acid rainwater samples were collected during 4 years from 1992 in Pusan area nearby seaside. Ionic composition of early and succeeding rainwater were investigated to identify emission sources. pH and Electronic Conductivity of samples were measured immediately after sampling. Major ion concentrations of rain samples were Na+, Ca2+, Mg2+, K+, NH4+, SO42-, NO3-, Cl- which were analyzed by ion Chromatography. 55% of early rainwater and 90% of succeeding rainwater were identified below pH 5.6. Because, Na+, K+, Ca2+ were washed mostly in early rainwater, as a result, pH values were increased by increasing rainfall amounts. It was studied that pH value was varied from ambient ion component, rainfall, and rain intensity. From the principal component analysis result, the dominant components of acid rainwater were Na+, K2+, Mg2+, Ca2+, the elements were contributed soil and marine source, the second components nuts -SO42-, SO4a-, NO3-, nuts -Ca2+ originated from man - made source.

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An experimental investigation on the characteristics of the outdoor silicone rubber insulator due to nitrate ion of acid rain (옥외용 실리콘 애자의 산성비중 질산이온에 의한 열화특성 연구)

  • Kim, L.T.;Lee, J.H.;Kim, J.T.;Koo, J.Y.
    • Proceedings of the KIEE Conference
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    • 1996.11a
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    • pp.196-199
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    • 1996
  • In this paper, aging characteristics of outdoor silicone rubber insulator resulting from the acid rain have been investigated with regards to nitrate ion ($NO_3$). For this purpose, silicone rubber was aged by immersing into the nitric solutions with different level ph during 1500 hours and various tests(tracking, contact angle, $tan{\delta}$, breakdown voltage, SEM, EDS, FT-IR) were performed. It was observed that the degradation was increased to ph 2.5 slightly and highly at ph 1.5. And thus, it could be expected that there is certain critical point between ph 1.5 and 2.5, which leads to throught degradation.

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Effects of Artificial Acid Rain on Chemical Properties of Korean Forest Soils (인공산성우(人工酸性雨)가 삼림토양(森林土壤)의 화학적(化學的) 성질(性質)에 미치는 영향(影響))

  • Joo, Yeong Teuk;Kim, Young Chai
    • Journal of Korean Society of Forest Science
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    • v.83 no.3
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    • pp.280-285
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    • 1994
  • This study was conducted to investigate the effects of acid deposition on forest soil, major five Korean forest soils(Brown, Dark red, Gray brown, Red and Yellow, and Volcanic ash forest soils) The samples were subjected to receive 1200mm($100mm{\times}12$ times) of artificial acid rain adjusted to pH5.6, 4.0, 3.0 and 2.0. The results obtained of major importance are summarized as follow ; 1. Ca appeared mostly affected at pH treatment of 2.0, while less affected by other pH treatments. Leaching of Ca rapidly increased with increasing of artificial acid rain acidity and application times in Dark red forest soil. 2. In the cases of Mg, K and Na, they showed gradual increase with the addition of artificial acid rain. Mg and Na losses showed similar leaching patterns, but they didn't show difference among the five forest soils. 3. Exchangeable canon concentrations in the soil leachates, which looked slightly different among the five forest soils, were the highest in pH2.0 treatment. Hydrogen ion comsumption capability by exchangeable canon was the highest in Dark red forest soil followed by Volcanic ash, Red and Yellow, Gray brown and Brown forest soils when artificial acid rain were treated.

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A Study on the Performance Evaluation Method of Waterproofing-Seal as Leakage Cracks Repairing Material using on the Underground Structure (지붕용 톱코팅재의 내구성 향상에 관한 성능 및 평가방법에 관한 기초적 연구)

  • Park, Jin-Sang;Kang, Hyo-Jin;Oh, Sang-Keun
    • Proceedings of the Korea Concrete Institute Conference
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    • 2006.05b
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    • pp.517-520
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    • 2006
  • The waterproofing of Building on the roof has been exposed more underground or the other part of waterproofing than environmental factor(solar heat, UV, salt, acid rain, wind, temperature, snow, rain, etc.) or physical factor. So it must be have a waterproofing performance and it has a special technique for the maintaining of concrete durability. Therefore, exposed waterproof layer has to protected from UV, solar heat, rain and the outside environment also, to endurance durability methods spread face plate topcoat material on the waterproof layer. But, actuality faceplate waterproof layer of topcoat materials are unbearable to UV, solar heat and moisture etc. and it doesn't have adhesion with waterproof layer in the middle. So it happens to crack, separating and heaving etc. Therefore, in the study, we will suggest that using of the exposed roof waterproof layer topcoat materials test method manage rooftop waterproof layer for the durability and the stability.

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