• Title/Summary/Keyword: 산성화

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The Review of Metabolic Acidosis During Exercise (운동 시 대사적 산성화에 관한 고찰)

  • Yoon, Byung-Kon
    • Journal of the Korean Applied Science and Technology
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    • v.35 no.4
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    • pp.1433-1441
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    • 2018
  • The development of acidosis during intense exercise has traditionally been explained by the increased production of lactic acid which causes the release of a proton and the formation of the acid salt sodium lactate. Through this explanation, when the rate of lactate production is high enough to exceed cellular proton buffering capacity, cellular pH is decreased. This biochemical process has been termed lactic acidosis. This belief has been an interpretation that lactate production causes acidosis and fatigue during intense exercise. However, this review provides clear evidence that there is no biochemical support for lactate production causing acidosis and fatigue. Metabolic acidosis is caused by an increased reliance on nonmitochondrial ATP turnover. Lactate production is essential for muscle to produce cytosolic $NAD^+$ to support continued ATP regeneration from glycolysis. In addition, Lactate production consumes protons. Although lactate accumulation can be a good indirect indicator for decreased cellular and blood pH, that is not direct causing acidosis.

Comparison of Soil Physicochemical Properties According to the Sensitivity of Forest Soil to Acidification in the Republic of Korea (우리나라 산림토양의 산성화 민감도평가와 그에 따른 토양 이화학적 특성 비교분석)

  • Lee, Ah Lim;Koo, Namin
    • Journal of Korean Society of Forest Science
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    • v.109 no.2
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    • pp.157-168
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    • 2020
  • The sensitivity of forest soil to acidification in the Republic of Korea (ROK) was evaluated based on pHH2O, cation exchange capacity (CEC), and base saturation (BS). Sensitivity to acidification was categorized into three grades: adequate level (AL, pH ≧ 4.2, CEC ≧ 15cmol/kg, BS ≧ 15%), caution level (CL, at least one indicator is below AL), and severe Level (SL, all three indicators are below AL). Soil samples were collected from the 65 stationary monitoring plots (40 × 40 ㎢), distributed throughout ROK. Only 19% of soil samples were classified as AL, while 66% and 15% were CL and SL, respectively. The median of pHH2O, CEC, BS, and Ca/Al indicator in AL soils was pH 4.64, 20.7cmol/kg, 29%, and 6.3, respectively. Moreover, BCex (K+, Mg2+, Ca2+) and available phosphorus (AP) concentration compared with a threshold value and molar ratio of BCex and AP to total nitrogen (TN) was high. This indicates that AL soils have a good nutrient condition. The molar Ca/Al ratio, an indicator for toxicity of exchangeable aluminum (Alex), was more than 1, indicating no negative impact of Alex on plant growth. On the contrary, the median of pHH2O, CEC, and BS in SL soils was pH 4.02, 13.2cmol/kg, and 10%, respectively. The Ca/Al index was less than 0.6, which indicates that negative impacts of Alex on plants were high. Furthermore, both the concentration of BCex in SL soils and the BCex/TN ratio were the lowest among the three acidity degrees. This shows that SLsoils can be degraded by soil acidification compared with less acidic soils.

대기유래 유황이 농경지 토양에 미치는 영향 스코트랜드와 U.K의 사례

  • Langan S;Edwards T;Bain D;Wilson M.J
    • Proceedings of the Mineralogical Society of Korea Conference
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    • 1996.10a
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    • pp.81-89
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    • 1996
  • 영국을 비롯한 유럽의 많은 농경지에서는 대기 중으로 아황산가스의 방출량 감소로 유황의 천연공급이 적어짐에 따라 일부 농작물의 수량 감소로 이어졌다. 반대로 자연식생하의 토양에서는 이같은 산성물질의 강하로 산성화가 진행되고 있다. 산성화의 범위와 정도를 규명하기 위하여 산성 물질의 임계부하량 연구를 추진하게 되었다. 이 결과 스코틀랜드의 많은 지역의 토양이 부하량 이상으로 산성물질이 강하되어 식물 및 생태계생존과 다양성을 위협하는 것으로 나타났다.

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Removal of Uranium from U-bearing Lime-Precipitate using dissolution and precipitation methods (우라늄 함유 석회침전물의 용해 및 침전에 의한 U 제거)

  • Lee, Eil-Hee;Lee, Keun-Young;Chung, Dong-Yong;Kim, Kwang-Wook;Lee, Kune-Woo;Moon, Jei-Kwon
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.10 no.2
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    • pp.77-85
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    • 2012
  • This study was carried out to remove (/recover) the uranium from the Uranium-bearing Lime Precipitate (ULP). An oxidative dissolution of ULP with carbonate-acidified precipitation and a dissolution of ULP with nitric acid-hydrogen peroxide precipitation were discussed, respectively. In point of view the dissolution of uranium in ULP, nitric acid dissolution which could dissolved more than 98% of uranium was more effective than carbonate dissolution. However, in this case, uranium was dissolved together with a large amount of impurities such as Al, Ca, Fe, Mg, Si, etc. and some impurities were also co-precipitated with uranium during a hydrogen peroxide precipitation. On the other hand, in the case of carbonate dissolution-acidified precipitation, U was dissolved less than 90%. Therefore, it was less effective than nitric acid dissolution for the volume reduction of radioactive solid waste. However, it was very effective to recover the pure uranium, because impurities were hardly dissolved and hardly co-precipitated with uranium.

A Review on Ocean Acidification and Factors Affecting It in Korean Waters (우리나라 주변 바다의 산성화 현황과 영향 요인 분석)

  • Kim, Tae-Wook;Kim, Dongseon;Park, Geun-Ha;Ko, Young Ho;Mo, Ahra
    • Journal of the Korean earth science society
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    • v.43 no.1
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    • pp.91-109
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    • 2022
  • The ocean is a significant sink for atmospheric anthropogenic CO2, absorbing one-third of the total CO2 emitted by human activities. In return, oceans have experienced significant declines in seawater pH and the aragonite saturation state also called ocean acidification. This study evaluates the distribution of aragonite saturation state, an indicator to assess the potential threat from ocean acidification, by combining newly obtained data from the west coast of South Korea with previous datasets covering the Yellow Sea, East Sea, northern South China Sea, and southeast coast of South Korea. In general, offshore waters absorb atmospheric CO2; however, most of the collected water samples show aragonite oversaturation. On the southeast coast, the aragonite saturation state was significantly affected by river discharge and associated variables, such as freshwater input with nutrients, seasonal stratification, biological carbon fixation, and bacterial remineralization. In summer, hypoxia and mixing with relatively acidic freshwater made the Jinhae and Gwangyang Bays undersaturated with respect to aragonite, possibly threatening marine organisms with CaCO3 shells. However, widespread aragonite undersaturation was not observed on the west coast, which receives considerable river water discharge. In addition, occasional upwelling events may have worsened the ocean acidification in the southwestern part of the East Sea. These results highlight the importance of investigating site-specific ocean acidification processes in coastal waters. Along with the above-mentioned seasonal factors, the dissolution of atmospheric CO2 and the deposition of atmospheric acidic substances will continue to reduce the aragonite saturation state in Korean waters. To protect marine ecosystems and resources, an ocean acidification monitoring program should be established for Korean waters.

Ecological Study of Regenerations in Experimental Canopy Gaps of a Fagus Sylvatica Forest in Germany (독일 너도밤나무(Fagus sylvatica L.) 숲 틈새에서의 갱신생태학적 연구)

  • 변무섭
    • Korean Journal of Environment and Ecology
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    • v.17 no.2
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    • pp.144-152
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    • 2003
  • The purpose of this study was to investigate the effects of lime fertilization and light intensity on beech regeneration strategy in a mature beech forest(ca. 150 years old) gaps, which was located in the soiling areas Germany, where the soil is an acid brown earth. For the experiment canopy gaps of 30m diameter were cut, and one canopy gap remained as untreated while the other was limed(3t dolomite h $a^{-1}$). Soil chemistry, soil water potential, light intensity(PAR), ground vegetation, beech seedlings and mycorrhiza were investigated along transect from the stands into gaps to the north. The results of this study are followings: 1) In the limed gap, soil chemistry was greatly improved and a vigorous herb layer developed as compared to the unlimed gap. 2) Development and growth of the beech seedlings in the unlimed gap were generally deficient. Specially, developments of lateral roots were very lack. 3) Through the lime fertilization, the minerals contents of beech leaves such as calcium(Ca) and magnesium(Mg) were increased, while manganese(Mn) was decreased. There was antagonism between potassium(K) and calcium(Ca) or magnesium(Mg). 4) The relative mycorrhiza frequency(RM) in beech seedlings of the southern edge was very higher than that of the middle part, and through the lime fertilization extension of the species Laccaria amethystina appeared clearly. The results of this study showed that lime fertilize in forest, where the soil is acid, will be necessary..