• 제목/요약/키워드: Secondary Pollution

검색결과 248건 처리시간 0.027초

A Study on Sterilization Characteristics of Elliptical Reactor by Using Xenon Flashlamp and Photocatalyst (Xenon flashlamp와 광촉매를 이용한 타원형 반응기의 살균 특성에 관한 연구)

  • Lee, Dong-Gil;Hong, Ji-Tae;Choi, Kyoung-Hwa;Cha, Jae-Ho;Kim, Hong-Ju;Kim, Hee-Je
    • The Transactions of The Korean Institute of Electrical Engineers
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    • 제58권3호
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    • pp.559-565
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    • 2009
  • In this paper, we invented a new and unique technique for the sterilization of Escherichia coli(E. coli) in polluted water. We applied a rich ultra-violet(UV) light from pulsed xenon flashlamp and photocatalyst(TiO2) to sterilize E. coli in polluted water. This method based on the use of UV light and photocatalyst is eco-friendly and does not cause secondary pollution. The proposed elliptical reactor is able to concentrate on quartz sleeve coated TiO2 or general quartz sleeve. The primary objective of our research was to determine the important parameters such as pulse repetition rate and input voltage and to know on the sterilizing efficiency of quartz sleeve coated TiO2 and general quartz sleeve. We obtained to achieve 99.999% sterilization in as little as 6 pulses at 800V in case of quartz sleeve coated Ti02, and 10 pulses at 800V in case of general quartz sleeve for 5 minutes. Although transmitted light of quartz sleeve coated TiO2 is deceased, the sterilizing efficiency is increased by 40% than general quartz sleeve. The reason of high sterilizing efficiency is that generated hydroxyl radical(OH) by photocatalyst and is able to concentrate light at a focus by using elliptical reactor.

The Determination of TRC using an Electrochemical Method (II: Pt electrode) (전기화학적 방법의 TRC(Total residual chlorine) 측정 연구(II: Pt전극 이용))

  • Lee, JunCheol;Pak, DaeWon
    • Journal of Korean Society on Water Environment
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    • 제30권3호
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    • pp.304-310
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    • 2014
  • The conventional methods for total residual chlorine such as iodometry and DPD colorimetric can cause secondary pollution due to additional agents, also have a wide error range. As for alternative, electrochemical method can measure TRC(Total residual chlorine), and is not required as additional agents, also very suitable for using the fields of ballast water because test time is relatively fast. Therefore, this study was investigated for changing charge by agitation, salt concentration, and temperature change. Charge showed differences based on changes of reduction peak with or without agitation. In contrast, TRC and charge were well correlated in constant agitation speed. As TRC and charge were analyzed with high correlations in constant salinity and temperature of ocean, thereby conductivity was firstly measured, and charge had high correlation for TRC in spite of changing salinity and temperature Pt electrode revealed high reliability ($r^2=0.960$) because it was rarely effected by TRC, On the other hand, Au electrode appeared inadequate ($r^2=0.767$) to use sensor in less than 1.0 ppm of TRC. For high accuracy and detection of TRC, Pt and Au electrodes for test time were, respectively, 14 and 22 seconds. As a result, Pt electrode was more valuable than Au electrode in terms of response time.

A Study on the Development of Inhalation Equipment for Seabed Sediment by the Difference of Water Head (수두차를 이용한 해저퇴적물 흡입장비 개발에 관한 연구)

  • Lee, Young-Gill;Son, Choong-Yul;Jeong, Uh-Cheul;Kim, Kang-Sin;Jeong, Kwang-Leol
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 한국해양공학회 2006년 창립20주년기념 정기학술대회 및 국제워크샵
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    • pp.261-264
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    • 2006
  • This paper deal with development of dredging equipment that proper water head elimination method changing transitional dredging method. Numerical simulation and model test were accomplished for development of seabed sediment inhalation equipment using water head. Sediment elimination system by the difference of water head has been analysed by numerical method. Model test was achieved for inhalation equipment performance test using water head by primary design. Also sediment elimination system has designed and developed that doesn't occur secondary pollution phenomenon. To verify the numerical results are compared with experimental results.

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The Construction of the Automatic Object Targeting System for Sailing Lookout (차세대 항해 견시를 위한 선박 자동추적 시스템 구축)

  • Kim, Ki-Uk;Lee, Byeong-Geol
    • Journal of the Korea Institute of Information and Communication Engineering
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    • 제17권7호
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    • pp.1583-1588
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    • 2013
  • According to 2008 statistics, there is a need for sailing lookout to minimize the ships collision that caused a secondary damage such as environment pollution and it happened 25 percentage rate. The aim of this study is to construct the object targeting system for notifying the sailing and ship information as monitoring the marine with CCTV having a zoom, rotation, and tile function. In this study we expected to induce the safety sailing by offering the CCTV automatic treatment.

Derivation of New Box Model to Analyze the Air Pollution Trends in a Metropolitan Area (대도시 대기오염 추세 분석을 위한 새로운 박스모델의 유도)

  • Kim Seogcheol;Joh Seunghun
    • Journal of Korean Society for Atmospheric Environment
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    • 제21권3호
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    • pp.377-397
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    • 2005
  • A new box model is proposed to describe the dynamic trend of the spatially averaged concentrations of pollutants over a large urban area such as metropolitan Seoul. Being averaged temporally and spatially over a thresh-hold scales, the dynamics of the pollutant concentration becomes simple enough that the governing equation can be expressed in an explicit algebraic form as a function of several meteorological factors and the pollutant emission rate. The single most important meteorological factor is the wind speed dominating the daily variations of the pollutant concentrations. Given the meteorological data from the surface station in the metropolitan Seoul, the model concentration shows excellent agreement with observations from January 1, 1990 to December 31, 2000: the modeling uncertainty, for example, of $NO_2$ concentrations, defined as mean differences between the model concentrations and observations is $16\%$ of the model concentrations. Even for $PM_{10}$ of which secondary sources are considered to be very important and simple box model is irrelevant to, the model performance turns out good, modeling uncertainty being about $32\%$.

Environmental Impact Assessment of Uranium Anormaly in Stream System around the Shinbo Talc Mine (신보활석광산 주변에 형성된 우라늄 이상치가 지표수계 환경에 미치는 영향)

  • 나춘기;정재일
    • Economic and Environmental Geology
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    • 제33권4호
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    • pp.261-271
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    • 2000
  • In order to evaluate the environmental impact of U anormaly in the drainage system around the Shinbo talc mine area, U contents, their distribution patterns, bioaccumulation and a-radioactivity in stream water, stream sediments and aquatic organisms were investigated. The U contents of stream water attenuated with increasing distance from the mine area. The same attenuation pattern is shown in stream sediments from mine to 0.75 km downstream, although these contain highly enriched U contents (24~83 mg/kg) comparing with the international average concentration of surface soils (0.79~11 mg/kg). However, U content increases abruptly in sediment at 1.5 km downstream, probably due to detrital migration and rediposition of U enriched sediments. Futhermore, enriched U in downstream sediments occur in high proportions of carbonate and Fe-Mn oxide bounded forms, which show high potential of a secondary pollution source. For aquatic organisms, bio accumulation degree of U are in the order: aquatic larvae>black snail>mountain frog>crawfish. Cultured trout by the U enrich groundwater (387 ${\mu}g$/l) shows U accumulation in the part of branchia (CRs 5.25) and bones (CRs 11.2) but not in flesh (CRs 0.03). Total a-radioactivity have been measured in the level as 0.47 nCi/l for groundwater, 2.94~18 nCi/kg${\cdot}$DW for organisms and 93~328 nCi/kg${\cdot}$DW for sediments.

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The Study on the Noise Contributing Factors Extraction of the Passenger Diesel Engine(I) (승용 디젤엔진 소음 기여인자 추출에 관한 연구(I))

  • Kim, Sung-Hun;Kwon, Yong-Jun;Ko, Pil-Kyu;Jung, Yeon-Uk;Lim, Ock-Taeck
    • Transactions of the Korean Society of Automotive Engineers
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    • 제19권3호
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    • pp.90-98
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    • 2011
  • Noises from diesel engine are the major issues for noise pollution as well as affect customers' purchasing needs to vehicles powered by diesel engine. This study investigates to screen-out main factors that contribute to noises from diesel engine using VGT 2000cc engine developed recently. Changes of fuel temperature, intake temperature and the presence of three way catalyst don't affect the 'Engine Radiation Noise' and the solely three way catalyst influence on the 'Tail Pipe Noise'. Especially, there are no effects of the presence of three way catalyst on torque, which is main subject that should be considered in secondary study.

Development of a Towing Simulation System for the StrandedTankers (좌초 유조선의 예인 시뮬레이션 시스템 개발)

  • Chun T.B.;Yu J.S.;Gong I.Y.
    • Journal of the Korean Society for Marine Environment & Energy
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    • 제3권1호
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    • pp.70-75
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    • 2000
  • It is important that effective and rapid response should be taken in the initial stage of the tanker accidents. A towing simulation system is essential to train in-site salvors for tile effective response in the tanker accidents. Training this system will help the marine environment to be protected from the oil pollution which could be proceed further by the secondary accidents. It this study, the towing simulation system using the TIS(Towing vessel Information System) was established, and ground reaction force was calculated using the simplified methods. This system will be useful for evaluation of towing procedures of oil tankers in stranding.

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The nonconserved N-terminus of protein phosphatases 1 influences its active site

  • Xie, XiuJie;Huang, Wei;Xue, ChengZhe;Wei, Qun
    • BMB Reports
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    • 제41권12호
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    • pp.881-885
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    • 2008
  • Protein phosphatase 1 consists of a secondary structure arrangement, conserved in the serine/threonine protein phosphatase gene family, flanked by nonconserved N-terminal and C-terminal domains. The deletion mutant of PP1 with the 8 nonconserved N-terminal residues removed was designated PP1-(9-330). PP1-(9-330) had a higher activity and affinity than PP1 when assayed against four different substrates, and it also demonstrated a 6-fold higher sensitivity to the inhibitor okadaic acid. This suggested that the N-terminal domain suppresed the activity of PP1 and interfered with its inhibition by okadaic acid. The ANS fluorescence intensity of PP1-(9-330) was greater than that of PP1, which implies that the hydrophobic groove running from active site in the truncated PP1 was more hydrophobic than in PP1. Our findings provide evidence that the nonconserved N-terminus of PP1 functions as an important regulatory domain that influences the active site and its pertinent properties.

A Study on Recognition of the Primary and the Secondary School Teachers on Water Environment Education (물 환경 교육에 대한 초.중등교사의 인식 연구)

  • Sung, Jung-Hee;Park, Tae-Yoon
    • Hwankyungkyoyuk
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    • 제23권4호
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    • pp.56-69
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    • 2010
  • The purpose of this research is to find out teachers' understanding and recognition about the water and the water environment education and to suggest the strategies of water education at school based on survey results. Results of the study are as follows: First, teachers had high level of water related knowledge and awareness about importance of the water environment education. However, they showed low level of environment educational efforts and environment protection behaviour in daily life. Second, they had a little chance to have the educational training for the water environment education. Third, the water environment education at schools has been made in very restricted areas such as water related scientific knowledge and water pollution. Fourth, teachers pointed out the biggest obstacle for the water environment education would be the lack of teaching materials and the second biggest one was the lack of educational facilities at schools. Based on the survey results, it was found out that in order to improve the water environment education at schools, substantial research by the teachers shall be implemented for all teachers of every subject to build up their capacity in adapting the water education to their subjects.

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