• 제목/요약/키워드: environmental challenge

검색결과 374건 처리시간 0.02초

Living Building Challenge의 하수처리시스템에 대한 미생물 연료전지의 응용 (Application of Microbial Fuel Cells to Wastewater Treatment Systems Used in the Living Building Challenge)

  • 이채영;;한선기
    • 한국환경보건학회지
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    • 제39권5호
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    • pp.474-481
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    • 2013
  • Objectives: This study was conducted to investigate the application of microbial fuel cells (MFCs) to the wastewater treatment systems employed in the Living Building Challenge. Methods: I reviewed a range of information on decentralized wastewater treatment technologies such as composting toilets, constructed wetlands, recirculating biofilters, membrane bioreactors, and MFCs. Results: The Living Building Challenge is a set of standards to make buildings more eco-friendly using renewable resources and self-treating water systems. Although there are various decentralized wastewater treatment technologies available, MFCs have been considered an attractive future option for a decentralized system as used in the Living Building Challenge. MFCs can directly convert substrate energy to electricity with high conversion efficiency at ambient and even at low temperatures. MFCs do not require energy input for aeration if using open-air cathodes. Moreover, MFCs have the potential for widespread application in locations lacking water and electrical infrastructure Conclusions: This paper demonstrated the feasibility of MFCs as a novel decentralized wastewater treatment system employed in the Living Building Challenge.

Bleomycin, Mitomycin C 및 Cadmium에 의한 CHO 세포의 적응반응 (Adaptive Response in CHO Cells by Bleomycin, Mitomycin C and Cadmium)

  • 김양지;한정호;정해원
    • 한국환경보건학회지
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    • 제18권2호
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    • pp.117-124
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    • 1992
  • Pretreatment with low concentration of Bleomycin and Cadmium rendered Chinese Hamster Ovary Cells more resistant to the induction of chromosome aberration by subsequent high concentration of same agent, however Mitomycin C did not function in that way. The cells pre-exposed to low dose of Cadmitim did not show cross-resistance to challenge dose of Mitomycin C for the induction of chromosome aberration, but cells pre-exposed to Bleomycin showed cross resistance. And the cells pre-exposed to low dose of Mitomycin C showed cross resistance to challenge of Bleomycin, but Cadmium did not.

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가스 및 유기용제용 호흡보호구의 정화통에 대한 수명예측방법의 정확도 및 타당성 검증연구 (Study on Accuracy and Validity Tests for Various Prediction Models for Gas and Vapor Respirator Cartridge Service Lives)

  • 박두용;박지영;윤충식
    • 한국산업보건학회지
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    • 제9권2호
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    • pp.19-31
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    • 1999
  • Most breakthrough tests are conducted at higher concentration levels compared to those in the field of air-purifying respirator applications. For example, typical challenge concentrations for breakthrough tests agains tcarbon tetrachloride are ranged between 250-1000 ppm although applicable concentrations range for air-purifying cartridge is 5-50 ppm for carbon tetrachloride. However, no guarantee has been made that isotherms derived from the experiment at high challenge concentrations could estimate adsorption capacity at the lower concentration range where workers wear usually air-purifying respirators. Three models of adsorption isotherms (Freundlich, Langmuir and Dubinin/Radushkevich(D/R) isotherms) that have been commonly applied for respirator cartridge testing were evaluated. Adsorption capacity at each challenge concentration was calculated from the Reaction Kinetic equation fitted for the breakthrough data. These data were used for derivation of three isotherms. In general, the D/R isotherm has given the best agreement between estimated adsorption capacities and experimentally measured. If the challenge concentration of 100 ppm is included for derivation of models, Freundlich and D/R models could succes sfully produced good estimations for adsorption capacities at 50 ppm level. Estimated adsorption capacities by both models ranged in 94 - 109 % of the experimentally measured. However, Langmuir model gives underes timation in all cases.

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공기 중 유기용제 농도수준이 방독마스크 정화통의 활성탄 흡착용량에 미치는 영향 (Effect of Airborne Organic Vapor Concentration Levels on the Adsorption Capacity of Charcoal in the Cartridges of Air Purifying Respirators)

  • 박두용
    • 한국환경보건학회지
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    • 제37권1호
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    • pp.50-56
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    • 2011
  • The adsorption capacity of charcoal is a function of the airborne concentration of the target chemical. To evaluate the adsorption capacity of charcoal packed in the cartridges of air purifying respirators, breakthrough tests were conducted with carbon tetrachloride for three commercial cartridges (3M models #7251, #6000 and AX) at 25, 50, 100, 250 and 500 ppm. Adsorption capacities were calculated using a mass transfer balance equation derived from the curve fitting to the breakthrough curves obtained experimentally. Carbon micropore volumes were estimated by iteration to fit the Dubinin/Radushkevich (D/R) adsorption isotherm. They were 0.6566, 0.5727 and 0.3087 g/cc for #7251, #6000 and the AX cartridge, respectively. Above 100 ppm (at high challenge concentrations), #7251 and #6000 showed higher adsorption capacities. However, as the challenge concentration decreased, the adsorption capacities of #7251 and #6000 sharply dropped. On the other hand, the adsorption capacity of the AX cartridge showed little change with the decrease of the challenge concentration. Thus, the AX showed a higher adsorption capacity than #7251 and #6000 at the 5-50 ppm level. It is concluded that service-life tests of cartridges and adsorption capacity tests of charcoal should be conducted at challenge concentration levels reflecting actual working environmental conditions. Alternatively, it is recommended to use the D/R adsorption isotherm to extrapolate adsorption capacity at low concentration levels from the high concentration levels at which breakthrough tests are conducted, at a minimum of two different concentration levels.

Industry's Response to the Green Movement

  • Little, Barry F.P.
    • 분석과학
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    • 제8권4호
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    • pp.1075-1078
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    • 1995
  • This paper describes how industry has responded to the environmental challenge. Benefits include compliance with environmental legislation; genuine reductions to environmental impact; sustainable improvements to profitability in the face of increased competitive pressure. National and international Standards for environmental management offer security and direction for a company wishing to improve environmental performance and coupled with a waste minimisation strategy many financial and environmental benefits can be achieved. Introduction of new technical skills, techniques and worker understanding to aid motivation is an essential component of such a strategy. Monitoring and targeting has a key role to play in the establishment of improved environmental performance.

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MUHAMMAD IQBAL AND ENVIRONMENTAL ETHICS

  • OZDEMIR, IBRAHIM
    • Acta Via Serica
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    • 제2권2호
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    • pp.89-112
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    • 2017
  • Today, we face many problems at the planetary, national, local, and personal level. What is interesting and important is the fact that the environmental crisis that we have been facing since the 1960s is seen by many environmentalists as a crisis of Western civilization, a slow collective suicide, and "the defining challenge of our age." This fact has encouraged many environmentalists, thinkers, and activists to turn to the wisdom of the East for a better and deeper understanding of nature and humanity for a sustainable future. Moreover, environmental, social, and economic threats are aimed at everyone without discrimination, be they Christian, Jew, Muslim, or Buddhist. Therefore, the very nature of the environmental crisis and challenge requires a cooperative, global response. In this context, this study suggests that Eastern societies may re-discover the richness of their own traditions in the light of pressing environmental problems and offer new insights to respond to these problems. This paper will explore the possibility and relevance of Sir Muhammad Iqbal's (1877-1938) ideas for an attitude of reverence and care for nature. It will suggest that his ideas could enlarge and enrich our perspective of ourselves vis $\grave{a}$ vis nature, and raise our "ecological consciousness" and moral responsibility to take action for the environment. It will be argued that Iqbal, as a great and towering son of the Silk Road and a bridge between East and West, is still relevant for us.

Selenium에 의한 흰쥐의 장기내 Metallothionein변화와 Cadmium에 미치는 영향 (Cadmium Toxicity Decreased by Selenium Induced Metallothionein in the Organs of Rat.)

  • 김정현;이재형;기노석;고대하
    • 한국환경보건학회지
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    • 제18권1호
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    • pp.95-104
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    • 1992
  • The influence of selenium to several toxic effects of cadmum, including lethality has been shown following pretreatment with cadmium, zinc and seleniurm Five groups of rats, each consisting of 16 rats, were studied and each group was divided into four subgroups, 4 rats for each subgroup. After subcutaneous pretreatment during 5 days with saline, CdCl$_{2}$ (0.5mg/kg, ZnCl$_{2}$ (13.0mg/kg) and $Na_{2}SeO_{3}$(1.0mg/kg), rats were given intraperitioneal administration of various dosage of or cadium of cadmium and selenium. After giving the challenge dose, cadmium and metallothionein(MT) concentrations were determined in liver and kidney The concentration of cadmium in liver and kideny increased proportionally to the increase of challenge dosage. The simultaneous administration of cadmium and selenium significantly more decrease cadmium concentrations in liver and kidney than those of the administration of cadmium only. However, MT concentrations in liver and kideny were increased by the pretreatment of cacmium, zinc and selenium. Our results suggest that increasing cadmium concentrations, gradully accumulating in the tissues of liver and kidney as a result of the pretreatment, served to induced the synthesis of MT, thus making them resistant to the challenge from cadmium.

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