• Title/Summary/Keyword: water corrosion

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A Study on Heavy Metals at the Consumer s Tap in Seoul (서울市 一部 水道栓水中 重金屬에 관한 調査硏究)

  • Lee, Byung Mu
    • Journal of Environmental Health Sciences
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    • v.10 no.2
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    • pp.41-51
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    • 1984
  • This study was performed using samples collected at Myungryundong and at Reservoirs. The purpose of this study was to investigate the differences of water quality between tap and raw water, and to analyse drinking water quality by Fe, Zn from corroded galvanized steel pipe. Results were as follows 1. The older the pipe was, the higher the concentration of Ferrum and Zinc was (t-test : p<0.05). Ferrum and Zinc also exceeded the limits in the older galvanized steel pipe. I think that this comes from the corrosion of pipe. 2. Mercury, Arsenic, Cadmium, Lead, Chomium, Argentum and Aurum not detected in raw water were not detected in tap water. Cobalt, Bismuth and Molybudenum detected in raw water were not detected in tap water. I think that this comes from the quality of raw water, the result of water treatment and the improbability of detection of above metals in water delivery system. 3. Silicon measured 2.4698ppm in raw water, but it ranged from 0.4769ppm to 1.982 ppm in tap water. Manganese measured 0.0638ppm in raw water, but it ranged from 0.0026ppm to 0.0198ppm in 17cases(31%) out of 55samples in tap water. I think that this comes from the water treatment. 4. Aluminium not detected in raw water was found in 17 cases (31%) out of the samples (55cases). It may be considered as the use of coagulants $Al_2(SO_4)_3$. $18H_2O$ and PAC (Poly Aluminium Chloride). The concentration of copper in tap water was much higher in 2 cases(3.6%) out of the samples(55) than that of copper in raw water. I think that this may come from the use of ${CuSO}_4$, the preventive of algae growth, and the result of chlorination, but further study must be necoessary to support the proof.

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Recent Development in Ultrasonic Guided Waves for Aircraft and Composite Materials

  • Rose, Joseph L.
    • Journal of the Korean Society for Nondestructive Testing
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    • v.29 no.6
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    • pp.525-533
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    • 2009
  • Emphasis in the paper is placed on describing guided wave successes and challenges for applications in aircraft and composite materials inspection. Guided wave imaging methods discussed includes line of sight, tomography, guided wave C-scan, phased array, and ultrasonic vibration methods. Applications outlined encircles lap splice, bonded repair patch, fuselage corrosion, water loaded structures, delamination, and ice detection and de-icing of various structures.

Characteristics of Pyrophyllite Aggregate fired at Low Temperature(II) (저온소성 납석질 벽돌의 특성에 관한 연구(저온소성 ladle용 벽돌의 개발연구 제이보))

  • 지응업;한기성;최상욱
    • Journal of the Korean Ceramic Society
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    • v.12 no.2
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    • pp.3-9
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    • 1975
  • The continuous grading method of pyrophyllite particles was adopted to prepare the refractories for ladle. The optimum conditions of fabrication adjusting the binders, the amount of water, the forming pressure and the firing temperature were investigated. The various properties, such as strength, density, porosity, thermal shock, corrosion resistance to slag were measured and compared with properties of ladle bricks presently used at local steel plants. The specimen studied in the present investigation showed a rather superior properties to theconventional product available locally.

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Manufacturing technology of two-layer self bonding insulating tape (이중절연 자기융착테이프 제조기술)

  • 조용석;이철호;심대섭
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.07a
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    • pp.890-893
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    • 2001
  • Two-layer self bonding insulating tape consists of butyl rubber(IIR ; Isobutylene-isoprene rubber) adhesive layer and polyethylene protective film. Butyl rubber have inherent characteristics such as resistance to corrosion and water, low temperature flexibility, excellent electrical insulating properties also resistance to environmental effect such as ozone and ultraviolet. Polyethylene film was used for the purpose of good insulating properties and resistance to ozone and ultraviolet. The tape was manufactured using extrusion and calender method.

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Round robin test for flaw sizing of piping weld (배관 용접부 결함 평가에 대한 round robin test)

  • 윤병식;김용식;양승한;김영호;이희종
    • Proceedings of the KWS Conference
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    • 2004.05a
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    • pp.308-310
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    • 2004
  • 1980년대 초 미국의 비등형 경수로(Boiling Water Reactor : BWR) 원자력발전소 배관계통의 입계 응력 부식 균열(Inter-Granular Stress Corrosion Crack) 검사 결과 및 미국 EPRI(Electric Power Research Institute)에서 실시한 round robin test 결과에서 기존 초음파 검사 방법의 실효성에 많은 문제점이 제기 되었다. (중략)

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Electrochemical Functionalized Water and Anti-Corrosion Research for Metal Surface (전기화학 기능수의 제조와 금속 표면에 대한 내식성 연구)

  • Jo, Seong-Ho;Choe, Won-Gyeong;Park, Su-Gil
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2014.11a
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    • pp.168-168
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    • 2014
  • 전기화학적으로 몇 가지 기능수를 제조하여 화학적, 전기화학적 특성을 확인하고 그 중 전해 환원수를 주요 타겟으로 하여 이를 금속 표면에 적용해 부식에 대한 영향을 실험적으로 확인하였다.

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