• Title/Summary/Keyword: Carbon dioxide ($CO_2$)

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Preparation of porous polymers by environmentally friend process in supercritical carbon dioxide (초임계 이산화탄소를 이용하는 친환경 공정에 의한 다공성 고분자의 제조)

  • 강세란;홍성수;이민규;이석희;천재기;주창식
    • Journal of Environmental Science International
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    • v.13 no.3
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    • pp.319-325
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    • 2004
  • An experimental study on the preparation of monolithic porous polymers by environmentally friend process in supercritical carbon dioxide has been carried out. Polymerization mixture composed of a cross-linking monomer, initiator and functional co-polymer was charged in the reactor with sapphire window. After the system was purged with a flow of $CO_2$ for 15 min, the reactor was pressurized with liquid $CO_2$ up to 100 bars. The reactor was isolated from and placed back to the system via quick connector for shaking until the mixture had become fully homogeneous. The reactor was then heated and pressurized to the required reaction conditions and left overnight. After cooling and $CO_2$ evacuation, the polymer was removed from the reactor as dry, white, continuous monoliths. The effect of experimental conditions on the physical properties of porous polymer was systematically examined, and it was found that monomer content had a major effect on the physical properties of the polymers.

A Study of Carbon Dioxide Emissions due to the Performance Degradation Factors of An Inner Network (내부 네트워크의 성능저하요인에 따른 이산화탄소 배출에 관한 연구)

  • Jeon, Jeon-Hoon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.11B
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    • pp.1315-1322
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    • 2011
  • Recently, The Problem of Global Warming around the world, is emerging as a very serious environmental problems, and as a way to fix it 'Green IT' is becoming an Issue. In these situations the evolution of network technologies with a various attacks, it appears, add the different security devices and systems are deployed. But, Deployment methods such a network, the performance and security of the internal network will affect on the greater and it will be increase Carbon Dioxide emissions. Therefore, In this paper, it will be to analyze Carbon Dioxide Emissions due to the Performance Degradation Factors of An Inner Network. and In a future, This paper is expected to serve as a valuable Information for the Network Performance and Security improvements and to reduce Carbon Emissions in the Field of IT.

An Experimental Study on the $CH_4{\;}/{\;}Air{\;}/{\;}CO_2$ Counterflow Diffusion Flame ($CH_4{\;}/{\;}Air{\;}/{\;}CO_2$ 대향류 확산화염에 대한 실험적 연구)

  • Lee, Chong-Won;Lee, Chun-Beom;Shin, Hyun-Dong
    • 한국연소학회:학술대회논문집
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    • 2001.06a
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    • pp.31-45
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    • 2001
  • The effect of adding carbon dioxide to methane-air flame was investigated experimentally. Measurements included extinction limits, flame temperature and photographic investigation of flame. A diffusion flame was stabilized between counterflowing streams of methane diluted with carbon dioxide and air diluted with carbon dioxide. Extinction limits and temperature for such flames were measured over a wide parametric range and were compared with those for other flames that fuel or oxidant was diluted with nitrogen or argon. The experimental results indicate that extinction phenomena can be explained by thermal effect and as an amount of carbon dioxide in fuel or oxidant increases, greatly as compared with other flames flame-temperature falls and flame-thickness is reduced.

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Analytic Expectation of Carbonation Depth of Indoor Concrete According to CO2 Concentration (건축물 실내 CO2 농도 분포에 따른 콘크리트 탄산화 깊이 산정에 관한 연구)

  • Park, Dong-Cheon;Park, Kun-Suok;Ahn, Jae-Cheol;Kang, Byung-Hee
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2011.11a
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    • pp.231-233
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    • 2011
  • Carbon dioxide in atmosphere causes concrete carbonation which is the phenomenon, that is, the pH of concrete changes from 12-13 to 8.85-10. Even though the carbon dioxide concentration of indoor is higher than that of outdoor, the micro measurement has not carried out. The concentration of carbon dioxide was measured in three places. The data was used as boundary condition to FEM analysis for expectation of concrete carbonation depth. The affect of building finish materials to concrete carbonation was discussed.

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The Fundamental Properties of Carbon Dioxide Absorption Concrete using Photosynthetic Bacterium Added (광합성균을 첨가한 이산화탄소 흡수 콘크리트의 기초적 특성)

  • Lim, Ji-Hee;Lee, Gun-Cheol;Yoon, Seung-Joe;Jung, Jae-Ho;Kim, Young-Min
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2013.05a
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    • pp.73-74
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    • 2013
  • In this study, we examined the properties of the concrete for the adsorption of carbon dioxide by adding in photosynthetic bacteria. As for the experimental plan, we measured slump, carbon dioxide concentration and compressive strength. The findings revealed the non-plastic cement added with photosynthetic bacteria had the greatest flexibility and showed carbon dioxide absorption and condensation delay due to the sugar constituents of photosynthetic bacteria. Giver the progress in the studies on the strength development, it is estimated to be used as CO2 reduction concrete.

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Comparison of Environmental Load per Constructional Methods (Focus on Reinforced Concrete Structures and Steel-Frame Structures) (구조공법별 환경부하 산출·비교분석에 관한 연구 (철근콘크리트구조와 철골구조를 중심으로))

  • Moon, Joon-Ho;Lee, Hyun-Joo;Jung, Young-Chul;Kim, Tae-Hee;Kim, Kwang-Hee
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2011.05a
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    • pp.193-195
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    • 2011
  • Nowadays, climatic environment change has become a major issue in the world. This causes major emissions of carbon dioxide industries steel industry, thermal power industry, cement industry is essential in the reduction of carbon dioxide, which is based on total carbon dioxide emissions account for most of the construction industry in an effort to minimize the environmental load is needed. accordingly, through case studies, It can be induce the selection to minimize environmental load by comparing the output of quantitative energy consumption and carbon dioxide emissions per constructional methods. As a result of this study, RC Structure was less environmental load than SC structure.

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Chemical Absorption of Carbon Dioxide into Non-Newtonian Polyacrylamide Solution (Polyacrylamide 비뉴튼액체에서의 이산화탄소의 화학흡수)

  • Hwang, Byung-Jin;Park, Sang-Wook
    • Clean Technology
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    • v.14 no.4
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    • pp.281-286
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    • 2008
  • Absorption rate of carbon dioxide was measured in the aqueous polyacrylamide (PAA) solution containing triethanolamine (TEA) of $0{\sim}2.0\;kg\;mol/m^3$ in a flat-stirred vessel with an impeller of 0.05 m and agitation speed of 50 rpm at $25^{\circ}C$ and 101.3 kPa. The chemical absorption rate of $CO_2$ was estimated by mass transfer mechanism based on the film theory using the physicochemical properties containing the liquid-side mass transfer coefficient of $CO_2$ and the kinetics of reaction between $CO_2$ and TEA to compare with the measured rate. The aqueous PAA solution acted as a reducing agent by viscoelastic property of non-Newtonian liquid based on the same viscosity of the solution.

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Flux of Carbon Dioxide and Deposition Velocity of Ozone over Glycine max Canopy (대두 개체군에 있어서 $CO_2$$O_3$ 플럭스)

  • 김원식;이호준
    • The Korean Journal of Ecology
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    • v.23 no.1
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    • pp.39-43
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    • 2000
  • Carbon dioxide (CO₂) and ozone (O₃) fluxes were measured over Glycine max canopy using the bowen ratio energy balance method at Fuchu - 20 km west of Tokyo, in late July and late September 1996. The CO₂, and O₃, fluxes were influenced by variation in leaf area index (LAI) during the measuring period. When LAI was more than 3.0, the CO₂ flux was found to be positively correlated with photosynthetically active radiation (PAR). The O₃, flux was always positive with an average deposition velocity for this case of about 0.5 mol m/sup -2/s/sup -1/. A positive correlation existed between the deposition velocity of O₃ and CO₂ during the period of LAI>2.0.

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Reliability Evaluation of Accelerated Carbonation Results According to Carbon Dioxide Concentration (이산화탄소 농도에 따른 촉진 탄산화 결과의 신뢰도 평가)

  • Park, Dong-Cheon
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2022.04a
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    • pp.166-167
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    • 2022
  • The International Energy Agency(IEA) recommends that intergovernmental agreements reduce CO2 emissions by 2050 to about 50% in 2005 in its report. To realize these demands, it is suggested to actively utilize energy efficiency improvement technology, renewable energy, nuclear power, carbon dioxide capture & storage technology (CCS). In the field of building materials and cement, mineral carbonization technology is widely used. Inorganic by-products applicable to greenhouse gas storage include waste concrete, slag, coal ash, and gypsum. If the Mineral Carbonation Act is used, it is expected that about 12 million tons of greenhouse gases can be immobilized every year. Greenhouse gas immobilization using cement hydrate can be immobilized by injecting carbon dioxide into the hydrated products C-S-H, and Ca(OH)2. In the case of immobilization through concrete carbonization, a carbon dioxide promotion test is used, which is often different from the actual carbon dioxide carbonization reaction. If the external carbon dioxide concentration is abnormally higher than the reality, it is thought that it will be different from the actual reaction. In this study, the carbonation phenomenon according to the concentration and identification of the carbon dioxide reaction mechanism of cement hydrate was to be considered.

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Corrosion Control in Water Distribution System using Lime and Carbon Dioxide(I) - Determination of Optimum Operational Conditions in Lime Adding Process (소석회와 CO2를 이용한 상수관로의 부식제어(I) - 소석회 주입공정의 최적 운전인자 도출)

  • Sohn, Byung-Young;Byun, Kyu-Sik;Kim, Young-Il;Lee, Doo-Jin
    • Journal of Korean Society of Water and Wastewater
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    • v.22 no.3
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    • pp.373-378
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    • 2008
  • The pH & alkalinity adjustment method by lime and carbon dioxide($CO_2$) for corrosion control in water distribution system was investigated to determine the optimum operational condition in lime adding process in water treatment plant(WTP). The mixing time at dissolution tank and sedimentation time at saturator for maintaining optimal turbidity condition of lime supernatant were 60~75 minutes and 75~95 minutes, respectively. There was no difference according to $CO_2$ adding methods such as $CO_2$ saturated water or $CO_2$ gas. But, $CO_2$ saturated water could be convenience at WTP in terms of pH control and quantitative dosing. To minimize generation of calcium carbonate products, the short time interval between adding of lime and $CO_2$ is most important. The lime should be added below 32 mg/l for preventing pH rising and generation of calcium carbonate products at the heating condition.