• Title/Summary/Keyword: carbon effect

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Antimicrobial Effect of Carbon Dioxide on Microorganisms (이산화탄소의 항균 효과)

  • 홍석인;변유량
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.26 no.6
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    • pp.1258-1267
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    • 1997
  • Corbon dioxide id effective for extending the shelf-life of perishable foods by retarding microbial growth. The overall effect of carbon dioxide is to increase both the lag phase and generation time of microorganisms. However, the role of carbon dioxide in affecting the growth and metabolism of any given microorganisms is not clear yet, although its inhibitory effect is generally found at moderate to high concentrations. Systematic studies of the effects of carbon dioxide on microorganisms are therefore warranted. It is also necessary to understand the role of carbon dioxide in the preservation of foods as well as the control by carbon dioxide of fermentations of biotechnological importance. In this review, the antimicrobial effect of carbon dioxide on microorganisms is investigated in terms of its gas and solution properties, inhibition of microbial growth and specific metabolic processes, perturbation of membrane structure.

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A Survey of water pollution and the development of water treatment system on agricultural Area (농어촌의 수질오염과 수질특성에 적합한 정수 처리시스템의 개발에 관한 연구(1))

  • 정문호;김영규;조태석;배현주;신명옥;김수연;김민지;김민영;김수복
    • Journal of environmental and Sanitary engineering
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    • v.12 no.2
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    • pp.65-74
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    • 1997
  • The purpose of this study was to investigate the removal effect and variation of contaminated water by various water treatment processes using sediment filter, activated carbon, photocatalysis, reverse osmosis, ultra violet sterilizer and ultra filtration. The removal effect of chloride and trace metal was low by activated carbon and ultra filter but high in reverse osmosis. The removal effect of bacteria and E. coli was low by activated carbon and membrane filter system using activated carbon but high in impregnated activated carbon. The removal effect of TCE was low in sand and ultra filter system as compared with activated carbon. Ultra filtration process was effective for purify agricultural water without E.coli. Reverse osmosis was effective to remove heavy metal and activated carbon was effective to remove halogenated organic chemical compound. The flux and the removal effect of COD in spiral wound ultrafilter were higher than the hollow fiber ultrafilter.

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Effect of Triacetin and Activated Carbon on the Hardness of Cellulose Acetate Filter containing Activated Carbon (활성탄과 가소제가 탄소복합필터의 경도에 미치는 영향)

  • 신창호;김종열;김정열;김영호;이영택
    • Journal of the Korean Society of Tobacco Science
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    • v.22 no.2
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    • pp.157-163
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    • 2000
  • Filter hardness is important to filter and cigarette manufactures because it is directly related to the ability of a plugmaker during making filter and to the acceptability of the filter by the consumer. In general, glycerol triacetate(Triacetin, TA) is the currently used common plasticizer in making filters from cellulose acetate tow and the effect of triacetin on hardness of filter which is made of mono cellulose acetate tow was well known. But unfortunately, the effect of triacetin on the hardness of cellulose acetate filter containing ativated carbon(carbon filter) was not reported so far. In this study, we manufactured filters with various carbon content at different triacetin concentrations and then analyzed the filter hardness and pressure drop. Filter hardness was directly increased with triacetin concentration but pressure drop was not affected and the effect of carbon content on filter hardness was smaller than that of triacetin concentration. However, pressure drop was directly increased with carbon content.

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Environmental Performance, Carbon Emission Disclosure, and Carbon Emission Intensity on Cost of Equity Capital: An Empirical Study in Indonesia

  • MARSELITA, Octa;Lindrianasari, Lindrianasari;ALVIA, Liza;EVANA, Einde
    • The Journal of Industrial Distribution & Business
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    • v.12 no.11
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    • pp.9-16
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    • 2021
  • Purpose: Carbon emissions have now become a major concern around the world, especially for the government and private sector. Unfortunately, in Indonesia, disclosure related to company carbon emissions is still done voluntarily. This research aims to provide empirical evidence on the effect of environmental performance, carbon emission disclosure, and carbon emission intensity on the cost of equity capital. Research design, data, and methodology: This research uses secondary data with a sample consisting of Indonesia companies that are sensitive to the environment and listed on the Indonesia Stock Exchange in 2017-2019. The analytical tool used in this research was multiple regression models. Result: The study found a carbon emission disclosure had a significant positive effect on the cost of equity capital. Carbon emission intensity and company size had a significant negative effect on the cost of equity capital. Meanwhile, environmental performance did not have a significant effect on the cost of equity capital. Conclusion: Therefore, the results of this research are expected to provide feedback to the company's stakeholders that environmental performance and carbon emissions are some of the points seen by investors in making investment decisions.

A Study on the Removal Effect of Bacteria and E. Coli. by Water Treatment Processes using Activated Carbon and Membrane (정수처리공정에 따른 일반세균과 대장균군의 제거에 관한 연구)

  • 조태석;김영규;정문호
    • Journal of Environmental Health Sciences
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    • v.23 no.2
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    • pp.24-27
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    • 1997
  • This study has been designed to check the removal effect of contaminated water by various water treatmemt processes using sediment filter, activated carbon, reverse osmosis membrane, ultra vilolet sterilizer and ultra filtration and then to analyze the change of pH, the concentration of chlorides, bacteria and E. coli. after 24 hours. pH has increased as much as 0.15-0.32 by activated carbon but decreased sharply by reverse osmosis treatment after 24 hours. The removal effect of chloride was low by activated carbon and ultra filter but high in reverse osmosis. The removal effect of bacteria and E. coli was low by activated carbon and membrane filter system using activated carbon. Ultra filtration process was effective for purify agricultural water containg bacteria and E.coli.

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An Experimental Study on the Strengthening Effect of RC Beam with Carbon Fiber Grid (탄소섬유그리드를 이용한 RC보의 보강효과에 관한 실험적 연구)

  • Shim, Nak-Hoon;Kim, Jeong-Jae;Park, Young-Suk
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.6 no.4
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    • pp.107-118
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    • 2002
  • The purpose of this study is to investigate the strengthening effect of RC beams with carbon fiber grid. Carbon fiber grid that is very lightweight and stronger than steel reinforcement does not rust or corrode and has a very high resistance to salt. In this study, five real size specimens which are strengthened with different types of carbon fiber grid are tested. With the results of this tests, we found the physical and mechanical properties of carbon fiber grid and polymer mortar which are used to strengthen the damaged or cracked reinforcement concrete beams. we also investigate the strengthening effect of carbon fiber grid on the five flexural test specimens that have cracks.

Carbon Emission Analysis Considering Demand Response Effect in TOU Program (TOU 프로그램의 DR 효과를 고려한 탄소 배출 분석)

  • Kim, Young-Hyun;Kwag, Hyung-Geun;Kim, Jin-O
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.60 no.6
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    • pp.1091-1096
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    • 2011
  • Currently, the concern about the environment is the issue all over the world, and in particular, carbon emissions of the power plants will not be able to disregard from the respect of generation cost. This paper proposes DR (demand response) as a method of reducing carbon emissions and therefore, carbon emissions cost. There are a number of studies considering DR, and in this paper, the effect of DR is focused on the side of carbon emission reduction effect considering Time-Of-Use (TOU) program, which is one of the most important economic methods in DSM. Demand-price elasticity matrix is used in this paper to model and analyze DR effect. Carbon emissions is calculated by using the carbon emission coefficient provided by IPCC (Intergovernmental Panel on Climate Change), and generator's input-output characteristic coefficients are also used to estimate carbon emission cost as well as the amount of carbon emissions. Case study is conducted on the RBTS IEEE with six buses. For the TOU program, it is assumed that parameters of time period partition consist of three time periods (peak, flat, off-peak time period).

A Study on Improvement and Effect of Carbon Point Program for Residential Buildings in Daegu (대구광역시 주거 건축물의 이산화탄소 배출 감축을 위한 탄소포인트제의 효과 및 개선방향에 관한 연구)

  • Yeo, Myung-Kil;Jeon, Gyu-Yeob;Hong, Won-Hwa;Cho, Woong-Ho
    • Journal of the Korean housing association
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    • v.23 no.4
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    • pp.11-18
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    • 2012
  • The amount of energy consumption in the buildings is approximately 20% of domestic energy consumption. The Carbon Point Program have been published on reduction of greenhouse gas emission in buildings under the paradigm of 'Low Carbon Green Growth'. This study focuses on the effect of 'Carbon Point Program' for residential buildings in Daegu. The amount of electricity and waterwork consumption and information of households were investigated to analyse the effect of carbon point program. The samples are situated in Deagu and are apartment in Bukgu and Suseonggu. The $CO_2$ emission is analysed by factors of energy resource and household organization between before participating and after participating in Carbon Point Program. The participation type has a difference of voluntary participation in Suseonggu and passive participation in Bukgu. Based on this investigation, average amount of $CO_2$ emission was reduced from voluntary participation households but all of them did not. To promote the effect of Carbon Point Program, this study proposes that needing the plans to raise will and activity of reducing carbon and to help participation which have disadvantage against achieving reduction.

Effect of Carbonization Temperature on Carbon Dioxide Adsorption Behaviors of mesoporous carbon (중기공 탄소의 탄화온도에 따른 이산화탄소 흡착 거동)

  • Jang, Dong-Il;Park, Soo-Jin
    • 한국신재생에너지학회:학술대회논문집
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    • 2011.05a
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    • pp.221.1-221.1
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    • 2011
  • In this study, we prepared the nitrogen-containing carbon spheres with mesopore processed by a facile polymerization-induced colloid aggregation method including carbonization in order to investigate the characterization and the effect on their carbon dioxide adsorption behaviors. The carbonization temperature was varied in the range of $600^{\circ}C$ to $900^{\circ}C$. The nitrogen contents of the mesoporous carbon sphere were characterized using XPS. The carbon dioxide adsorption capacities of the prepared mesoporous carbon sphere were determined by the amounts of carbon dioxide adsorptions at 298 K and 1.0 atm. The results showed that the prepared mesoporous carbons were highly effective for the carbon dioxide adsorption due to the increasing the affinity of the basic functionalities of adsorbent surface to acidic carbon dioxide. Maximum adsorption capacities of carbon dioxide at $25^{\circ}C$ were achieved up to 106 mg/g.

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Pressure Effects on the Morphology Development of C/C Composites During Carbonization

  • Joo, Hyeok-Jong;Ryu, Seung-Hee;Ha, Hun-Seung
    • Carbon letters
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    • v.1 no.3_4
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    • pp.158-164
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    • 2001
  • It is well known that the fabrication process of carbon/carbon composites is very complex. Above all, the carbonization process have major effect on the morphology development of carbon matrix. Carbon/carbon composites of 4-directional fiber preform were fabricated using the coal tar based pitch as a matrix precursor in this study. According to carbonization pressure of 1 bar, 100 bar, 600 bar, and 900 bar, morphological changes of cokes and matrix of composites were discussed. As the carbonization pressure increased to 600 bar, the flow pattern morphology of bulk mesophse was well developed. On the contrary, mosaic pattern morphology was found in case of 900 bar of carbonization pressure. It is confirmed that the carbonization pressure have profound effect on the degree of graphitization and crystal size of carbon matrix. Even in the highly densified carbon/carbon composites, large voids were still found in the matrix pocket region.

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