• Title/Summary/Keyword: Rust

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CONSERVATION TREATMENT OF GOLD CROWN EXCAVATED FROM IMDANG-DONG TOMB (임당동 고분출토 금동관의 보존처리)

  • Lee, Oh-Hee
    • 보존과학연구
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    • s.7
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    • pp.48-55
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    • 1986
  • The gold crown unearthed from the ancient tombs at Imdang-dong, Kyongsan-gun, Kyongsangbuk-do was in a state of severe corrosion that its original pattern couldn't be identified. Therefore, for the conservation of the relics, the following methods are employed :1. With 10% formic acid are used for the elimination of the bronze-rust and then plated them with gold.2. As a rust-proof treatment, 1% Benzotriazole is used for stem corrosion as well3. For protection and reinforcement of the surface of the relics, 30% incralac agentsare used.4. Pieces of fragments are bonded together by cyanoacrylate and on the backside are coated partially with Araldite for the reinforcement of the glass-wool.5. Silica-gels are kept into the acryl box for perfect maintenance.

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Performance of Automotive Wheel Bearing Grease by Water Contents (수분함량에 따른 자동차용 휠베어링 그리스 품질특성 연구)

  • Lim, Young-Kwan;Lee, Eun-Hee;Lee, Joung-Min;Jeong, Choong-Sub
    • Tribology and Lubricants
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    • v.27 no.5
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    • pp.275-280
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    • 2011
  • Automotive wheel bearing grease helps to reduce stresses and prevent wear of wheel bearings. But it is easily contaminated by water and other contaminants. In this study, we investigated the property change of automotive wheel bearing grease under water contamination. The result showed that some properties such as dropping point, work penetration and oxidation stability were not influenced by water content. However, most of properties such as work stability, water washout characteristics, leakage tendency, oil separation, evaporation loss and rust protection became worse after water was added. This is thought that added water makes the interaction weak between thickener and base oil of grease.

Design Considerations to Enhance Perforation Corrosion and Life Prediction of Automotive Body Panel

  • Choi, Minsoo;Chung, Bumgoo;Choi, Jaewoong
    • Corrosion Science and Technology
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    • v.2 no.5
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    • pp.247-251
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    • 2003
  • The corrosion forms of automotive body panels are various. One of the representations is a corrosion pitting and its propagation on the lapped portion by galvanic corrosion. But it has been difficult in correlation analysis about the corrosion propagation rate and mechanism of pitting and the actual automotive body in field. This present study interprets experimentally the rust pitting occurrence mechanism on the lapped panels through experimental methods. And field car investigation was executed for correlation analysis with experimental results. This paper compares corrosion propagation rate by pitting on hot-dip galvannealed steel sheets with corrosion forms in the automotive field condition. The research fundamentals which make it possible to predict the pitting occurrence and propagation on the lapped panels in the actual vehicles are given.

Properties of Microbial Surfactant S-acid (미생물 계면활성제(S-acid)의 특성조사에 관한 연구)

  • 정해권;이정복임건빈김은기
    • KSBB Journal
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    • v.10 no.1
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    • pp.71-77
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    • 1995
  • Characteristics of S-acid and its derivatives, as biosurfactants, were investigated. Sodium salt of S-acid(S-lNa) effectively decreased the surface tension to near 30 dyne/cm and showed superior dispersing ability than commercial surfactants such as SDS and Tween 80. The emulsion made by S-lNa could be maintained even with increased concentration of calcium ion. Also the penetratlng ability of S-lNa was observed as effective as that of LAS. All derivatives of S-acid were degraded by microorganisms much faster than conventional surfactants. Among the derivatives, S-3Na prevented rust formation as effectively as commercial anti-rust agents did.

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Anti-oomycete Activity of Furanocoumarins from Seeds of Psoralea corylifolia against Phytophthora infestans

  • Shim, Sang-Hee;Kim, Jin-Cheol;Jang, Kyoung-Soo;Choi, Gyung-Ja
    • The Plant Pathology Journal
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    • v.25 no.1
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    • pp.103-107
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    • 2009
  • In the course of a searching natural antifungal compounds from plant seeds, we found that the methanol extract of Psoralea corylifolia seeds showed potent control efficacy against tomato late blight caused by Phytophthora infestans and wheat leaf rust Puccinia recondita. Under bioassay-guided purification, we isolated two furanocoumarins, psoralen and isopsoralen, with anti-oomycete activity against P. infestans. By 1-day protective application, both compounds strongly reduced the disease development of P. infestans on tomato seedlings, but hardly controlled development of leaf rust on wheat seedlings. This is the first report on the anti-oomycete activity of P. corylifolia as well as that of psoralen and isopsoralen.

토양 중 mineral에 의한 염소계 유기화합물 분해 특성 연구

  • Choi Jeong-Yun;Sim Sang-Gyu;Lee U-Jin
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2006.04a
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    • pp.33-36
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    • 2006
  • The reductive dechlorination of chlorinated organic compounds by soil minerals in soil and groundwater were carried out in this study. FeS, green rust, and magnetite were chosen as the representative soil minerals which were capable of degrading chlorinated compound in soil system. FeS was the most effective reductant in degradation of carbon tetrachloride. The reductive degradation of CT and 1,1,1-TCA by FeS was much faster than that of 1,2-DCB and 2,4-DCP. The reactivity of FeS was effectively improved by the addition of trace metals. The addition of Co to FeS suspension enhanced the reaction rate of 1,2-DCB by a factor of 46 compared to that by FeS without Co.

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Two Newly Identified Gymnosporangium Species, G. japonicum and G. cornutumn, in Korea

  • Yun, Hye-Young;Lee, Seung-Kyu;Lee, Kyung-Joon;Kim, Kyung-Hee
    • The Plant Pathology Journal
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    • v.19 no.6
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    • pp.274-279
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    • 2003
  • Two Gymnosporangium species, G. japonicum and G. cornutum, causing cedar-apple rust, were newly identified in Korea, and a new aecial host for each fungus was found by artificial inoculation. Detailed descriptions of the species were made based on macroscopic features (symptoms and signs) and light and scanning electron microscopic observations of spores and peridial cells. G. japonicum from Juniperus chinensis var. horizontalis had Photinia villosa as its new aecial host G. cornutum from J. rigida showed its aecial stage on Sorbus alnifolia.