• Title/Summary/Keyword: Perfluorocarbons

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Performance Based Evaluation of Concrete Carbonation from Climate Change Effect on Curing Conditions of Wind Speed and Sunlight Exposure Time (기후변화의 풍속과 일조시간 양생조건에 따른 콘크리트 탄산화 성능중심평가)

  • Kim, Tae-Kyun;Shin, Jae-Ho;Choi, Seung-Jai;Kim, Jang-Ho Jay
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.19 no.5
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    • pp.45-55
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    • 2015
  • Currently, extreme weather events such as super typhoon, extreme snowfall, and heat wave are frequently occurring all over the world by natural and human caused factors. After industrial growth in the 1970s, earth's temperature has risen sharply. due to greenhouse effect. Global warming can be attributed to gases emitted from using fossil fuel such as average carbon dioxide, perfluorocarbons, nitrous oxide, and methane. Especially, carbon dioxide has the highest composition of about 90%. in the fossile fuel usage emitted gas. Concrete has excellent durability as a building material climate change. However, due to various of physical and chemical environmental effect such as conditions during its curing process, the performance degradation may occur. Carbon dioxide in the atmosphere causes steel corrosion and durability decreases by lowering the alkalinity of concrete. Therefore, in this study, concrete durability performance with respect to carbonation from curing conditions change due to wind speed and sunshine exposure time. Concrete carbonation experiment are performed. using wind speed (0, 2, 4, 6) m/s and sunlight exposure time (2, 4, 6, 8) hrs. Also, performance based evaluation through the satisfaction curve based on the carbonation depth and carbonation rate test results are performed.

Study on the Methane Emissions from Pails Storing Liquid Swine Manure (Pail내 돈슬러리의 메탄 발생량에 관한 연구)

  • Choi, D.Y.;Park, K.H.;Kwag, J.H.;Cho, S.B.;Yang, S.H.;Hwang, O.H.;Kang, H.S.;Yoo, Y.H.
    • Journal of Animal Environmental Science
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    • v.16 no.3
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    • pp.175-180
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    • 2010
  • Many greenhouse gases occur naturally, such as water vapor, carbon dioxide, methane, nitrous oxide, and ozone. Others such as hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride ($SF_6$) result exclusively from human industrial processes. Current global warming has been linked to anthropogenic greenhouse gas concentration increases. Methods to quantify greenhouse gas emissions during animal agriculture and the possibility to apply those to circumstance in the world were studied. Various chamber methods with trace gas analyzer (TGA) were used to quantify greenhouse gas emissions from stored manure. Methane fluxes from pails storing liquid swine manure were measured. Methane emissions increased a little with time and mean was 393.2 ${\mu}g\;m^{-2}\;s{-1}$ (standard error : 4 ${\mu}g\;m^{-2}\;s{-1}$).