• 제목/요약/키워드: heavy material

검색결과 1,067건 처리시간 0.032초

생활폐기물 소각장 작업복의 중금속 분석 (Analysis of Heavy Metal Concentration on Working Clothes for Waste Incinerating Workers)

  • 박순자
    • 한국지역사회생활과학회지
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    • 제18권1호
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    • pp.39-53
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    • 2007
  • The purpose of this study was to determine the characteristics of an experimental protective clothing material with regard to comfort and isolation from the hazardous heavy metals produced in municipal waste incineration. An analysis was conducted on the total concentrations of heavy metals in some parts such as surface, middle layer, and interior for the treated fabric, and the untreated one, and working clothes. We conclude that the processed fabric with charcoal for working clothes showed the least exposure to heavy metals of the three. Working clothes worn by workers during waste incineration were much more contaminated than the untreated and treated materials. The material of working clothes could be chosen according to the function with regard to its original chemical characteristics, which are the proper results of the dyeing process. The processed fabric material has high degrees of moisture regain, thermal insulation, water vapor penetration, and antibacterial function; consequently, it is much more comfortable to wear. The fabric material proposed in this research contributed much more to blocking heavy metal concentrations (such as Cd, Pb, Cu, Cr, Zn, Mn) than did the fabric of working clothes at present. Consequently, we strongly suggest that the material of working clothes be upgraded by adopting the above-mentioned charcoal-processed fabric. Materials of working clothes must be improved to increase comfort and prevent harmful gas, flying dust, and heavy metals from permeating the fabrics.

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유통 한약재의 중금속 잔류실태 조사 (Monitoring of Heavy Metal Contents in Commercial Herbal Medicines)

  • 장설;김태희;이아름;이아영;최고야;김호경
    • 한국약용작물학회지
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    • 제20권6호
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    • pp.434-439
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    • 2012
  • This study was conducted to determine the contents of heavy metal in commercial herbal medicines. The monitoring of lead, arsenic, cadmium and mercury was carried out on 100 samples with 10 kinds of herbal medicines. The contents of heavy metal were measured by inductively coupled plasma atomic emission spectrometry (ICP-AES) and mercury analyzer. The mean values of heavy metal contents for herbal medicines were Pb 1.87 mg/kg, As 0.39 mg/kg, Cd 0.26 mg/kg and Hg 0.021 mg/kg. Of the total samples, 19 samples (19%, 4 types) were violated the KFDA regulatory guidance of heavy metal in herbal medicines (9 samples on Pb, 10 samples on Cd). Among these 19 unsuitable samples, 16 samples were domestic and 3 samples were imported. Therefore, we need continuously monitoring to ensure confidence and safety for these herbal medicines.

감쇠재 사용에 따른 중량충격음의 소음 및 진동특성 (Noise and Vibration Characteristics of Heavy-weight floor impact by Using Damping Materials)

  • 전진용;정영;송희수;김민배;이영제
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2004년도 추계학술대회논문집
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    • pp.97-102
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    • 2004
  • The Characteristics of noise and vibration by heavy-weight floor impact sound was studied. Resonance frequency increased a little in structures that use damping material in living room and bedroom, and acceleration waves length that respond became short, and displayed aspect that oscillation level decreases. Result that measure sound pressure level, structure that compare and applies damping materials with structure that apply the resilient materials from 63Hz lower part that impact energy is concentrated in energy spectrum of heavy-weight floor impact sound displayed result that sound pressure, level decreases remarkably. Therefore, according to use of damping materials, confirmed reduction effect of heavy-weight floor impact sound.

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경량화 변압기 개발 (The Development of Light Weight Transformer)

  • 김종옥;윤자홍;김세창;서영우;송기동;오연호
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.37-40
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    • 2001
  • This paper describes a study for the development of light weight transformer with hybrid insulation system consists of A class insulation material and H class insulation material.

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인산염 마그네시아 시멘트에 의한 중금속 이온 고정화 (Solidification of Heavy Metal Ions Using Magnesia-phosphate Cement)

  • 최훈;강현주;송명신;정의담;김주성
    • 한국세라믹학회지
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    • 제48권1호
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    • pp.20-25
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    • 2011
  • Since 1980's, many mines have been closed and abandoned due to the exhaustion of deposits and declining prices of international mineral resources. Because of the lack of post management for these abandoned mines, Farm land and rivers were contaminated with heavy metal ions and sludge. We studied on the solidification/stabilization of heavy metal ions, chromium ions and lead ions, using magnesia-phosphate cement. Magnesia binders were used calcined-magnesia and dead-burned magnesia. Test specimens were prepared by mixing magnesia binder with chromium ions and lead ions and activators. We analyzed the hydrates by reaction between magnesiaphosphate cement and each heavy metal ions by XRD and SEM-EDAX, and analyzed the content of heavy metal ions in the eruption water from the specimens for the solidification and stabilization of heavy metal ions by ICP. The results was shown that calcined magnesia binder is effective in stabilization for chromium ions and dead-burned magnesia binder is effective in stabilization for lead ions.

Technology Research on Gas Turbine Combustor Utilizing Melt-Growth Composite Ceramics

  • Konoshita, Yasuhiro;Hagari, Tomoko;Matsumotoi, Kiyoshi;Ogata, Hideki;Ishida, Katsuhiko
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2004년도 제22회 춘계학술대회논문집
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    • pp.854-860
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    • 2004
  • "Research and Development of Melt-Growth Composite (MGC) Ultra High Efficiency Gas Turbine System Technology" program has been started in JFY2001. The main objective of the program is to establish basic component technologies to apply MGC material to an efficient gas turbine system successfully. It is known that MGC material maintains its mechanical strength at room temperature up to about 2000 K, which is ideal for the high temperature gas turbine. The purposes of the present study are to develop the cooling structure of the gas turbine combustor liner where MGC material is applied as the heat shield panel, also to develop the low NOx combustion system for a 1970 K (1700 deg.C) class gas turbine combustor. To start with, basic heat transfer characteristics were investigated by one-dimensional calculation and heat transfer experiment for the cooling structure. Axially staged configuration and fuel preparation were investigated by CFD calculation and experiments for the low NOx combustor.

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경량전철 추진시스템용 Linear Induction Motor의 경량화 (Light-Weight Linear Induction Motor for Light Railway Train)

  • 김기찬;이갑재;이정일;박정태;권중록;김종구
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 추계학술대회 논문집 학회본부 A
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    • pp.40-42
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    • 1999
  • In this paper, light-weight system of linear induction motor(LIM) for light railway train is presented, and is compared with former type of LIM. For the light-weight system without modification of motor size the material of primary core(silicon steel) is changed with iron-cobalt alloy and the material of primary winding(copper) is changed with aluminium. The characteristics of LIM are analyzed. Specially, the air gap magnetic flux density distribution due to end effect is showed with motor velocity, we will present papers continuously through designing and testing a trial product.

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선박용 전기추진시스템의 기술개발 동향 (A Trend of the Technical Development of Electric Propulsion Systems for Ships)

  • 박정태;이갑재;장성영;이광주;김종규;조성준
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 하계학술대회 논문집 B
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    • pp.958-960
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    • 2000
  • In this material, the characteristics and types of the electric propulsions for ships are examined and compared. And a trend on the technical developments of electric propulsion systems for ships are examined. So, this material will be a few helpful in researching and developing the electric propulsions for ships.

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마찰하전형(摩擦荷電型) 정전선별(靜電選別)에 의한 고비중(高比重) 플라스틱 혼합물(混合物)의 재질분리(材質分離)에 관한 연구(硏究) (A Study on Material Separation of Heavy Group Plastics by Triboelectrostatic Separation)

  • 전호석;백상호;박철현;김병곤
    • 자원리싸이클링
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    • 제16권2호
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    • pp.56-62
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    • 2007
  • 본 연구에서는 마찰하전형정전선별법을 적용하여 폐플라스틱 종말품으로부터 회수된 고비중 산물에 대한 재질분리 실험을 수행하였다. 하전장치의 재질선정을 위한 하전특성 연구결과, PP가 고비중 폐플라스틱의 재질분리에 가장 효과적인 하전재질로 확인되어, PP재질을 이용한 cyclone 하전장치를 개발하였다. 본 연구에서 개발된 cyclone 하전장치를 이용한 재질분리 실험결과, 최적 실험조건에서 PET의 품위와 회수율이 각각 98.5%와 86.2%인 결과를 얻어, 종말품 heavy group 폐플라스틱의 재활용을 위한 재질분리 기술을 확립하였다.