• Title/Summary/Keyword: heavy material

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

  • Park, Soon-Ja
    • The Korean Journal of Community Living Science
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    • v.18 no.1
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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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Monitoring of Heavy Metal Contents in Commercial Herbal Medicines (유통 한약재의 중금속 잔류실태 조사)

  • Jang, Seol;Kim, Tae Hee;Lee, Ah Reum;Lee, A Yeong;Choi, Goya;Kim, Ho Kyoung
    • Korean Journal of Medicinal Crop Science
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    • v.20 no.6
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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.

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

  • Jeon, Jin-Yong;Jeong, Young;Song, Hee-Soo;Kim, Min-Bae;Lee, Young-Je
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2004.11a
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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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Solidification of Heavy Metal Ions Using Magnesia-phosphate Cement (인산염 마그네시아 시멘트에 의한 중금속 이온 고정화)

  • Choi, Hun;Kang, Hyun-Ju;Song, Myung-Shin;Jung, Eui-Dam;Kim, Ju-Seng
    • Journal of the Korean Ceramic Society
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    • v.48 no.1
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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
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2004.03a
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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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Light-Weight Linear Induction Motor for Light Railway Train (경량전철 추진시스템용 Linear Induction Motor의 경량화)

  • Kim, K.C.;Lee, K.J.;Lee, J.I.;Park, J.T.;Kwon, J.L.;Kim, J.K.
    • Proceedings of the KIEE Conference
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    • 1999.11b
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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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A Trend of the Technical Development of Electric Propulsion Systems for Ships (선박용 전기추진시스템의 기술개발 동향)

  • Park, J.T.;Lee, K.J.;Jang, S.Y.;Lee, K.J.;Kim, J.K.;Cho, S.J.
    • Proceedings of the KIEE Conference
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    • 2000.07b
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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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A Study on Material Separation of Heavy Group Plastics by Triboelectrostatic Separation (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))

  • Jeon, Ho-Seok;Baek, Sang-Ho;Park, Chul-Hyun;Kim, Byoung-Gon
    • Resources Recycling
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    • v.16 no.2 s.76
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    • pp.56-62
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    • 2007
  • In this study, we carried out the research on triboelectrostatic separation for heavy group plastics (PET, PVC) recovered from wet gravity separation. From the research on charging characteristic for the choice of charging materials, it was found that PP was optimum charging material to make high charging amount with opposite polarity for PET and PVC of heavy group. Therefore, we manufactured a charger of cyclone type using PP material for separation of PET and PVC. At optimum test conditions that used PP cyclone charger developed in this study, we developed a triboelectrostatic separation technique that can separate PET plastic up to grade of 98.5% and recovery of 86.2%. We established new separation technology that could recycle the PET and PVC heavy group plastics recovered from wet gravity separation.