• Title/Summary/Keyword: Rust

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A study of the application of Hwangchil Tree (黃漆樹 Dendropanax morbiferus H.Lév.) in East Asia (동아시아에서 황칠수(黃漆樹)의 활용에 대한 연구(硏究))

  • Ahn, Young-su;Lyu, Jeong-ah
    • The Journal of Korean Medical History
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    • v.33 no.1
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    • pp.43-57
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    • 2020
  • Essence of the Hwangchil tree (黃漆樹 Dendropanax morbiferus H.Lév.) has been used for various purposes, like waxing emperor's armors, covering an astrology board, or, during the Silla Dynasty, burying it to block something bad in the soil symbolically. Essence of the Hwangchil tree was known to have remarkable preservation effects such as waterproofing, damp-proofing, rust-proofing, and moth-proofing as well as not being easily peeled off from even soft surfaces like paper. There is a record in Prescriptions for Epidemic diseases of Cows, Horses, Sheep, and Pigs (牛馬羊猪染疫病治療方), published in 1541, of Hwangchil that is local to Jeju Island being used instead of benzoin (安息香), of burning Hwangchil, and of making cows inhale its smoke to prevent plague among them. Along the same lines, there are records in the Local Chronicle of Tamra (耽羅志) and the Book of Earth Geography (輿地圖書) that identify Hwangchil with benzoin. In Seonghosaseol (星湖僿說), a book written by Lee Yik in around 1760, it is acknowledged that Hwangchil could be medicinal herb. In 2000, Ahn Duk-Kyun registered the roots and branches of Hwangchil tree as 'Boncho' (本草 herbal medicine) in the Pictorial Book of Korean Medicinals (韓國本草圖鑑) and presented the method of taking it for medical purpose. Researchers have suggested that Hwangchil essence as well as diverse parts of the plant such as its roots, branches, leaves, flowers, fruits, and gum have various meaningful medicinal properties. Regarding the history and recent researches of using Hwangchil tree, it has various medicinal probabilities such as, 'dispersing miasma' (辟邪), 'opening holes' (開竅), 'waking the heart' (醒心), 'smoothing spirits' (安神), 'piercing the block' (疎泄), 'removing the old and welcoming the new' (去故生新). This paper contributes ideas about how to expand the uses of Hwangchil Tree.

A study on the improvement of frictional performance of friction material for automobile brake by spray treatment (용사처리에 의한 자동차 브레이크용 마찰재료의 마찰성능개선에 관한 연구)

  • 김윤해;배창원;손태관
    • Journal of Advanced Marine Engineering and Technology
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    • v.22 no.1
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    • pp.67-76
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    • 1998
  • Friction materials for brake linings and clutches have severe performance requirements. The principal function of such frictional elements is to convert kinetic energy to heat, and then either to absorb or to dissipate heat. In order to achieve these objectives, the coefficient of friction must be as high as possible, independent of variations in operating conditions, and the necessary energy conversion must be accomplished with a minimum of wear on the contacting parts. In this study, Al powder, Al bronze powder and Mo powder used in general for automobile brake was sprayed on automobile brake disc to restrain rust and to maintain friction performance. Dynamo and corrosion tests have been carried out. It is concluded that the sprayed disc with Al bronze powder has the most improved frictional performance and anti-corrosive characteristics. The main results obtained can be summarized as follows; 1. From the corrosion current density test for gray cast iron and sprayed disc with powders of Al, Al bronze and Mo, it was cleared that the spray treatment with Al bronze powder showed the most superior anti-corrosive characteristics than other powders. 2. By anode polarization toward the noble direction from corrosion potential, corrosion current density with sprayed brake disc by Al-bronze powder was the lowest. 3. Mean frictional coefficients obtained from dynamo test are as follows : the sprayed disc with Al(99.99%) powder was 0.190 ; the sprayed disc with Al-bronze powder was 0.312 ; the sprayed disc with Mo powder was 0.257 ; the non-sprayed disc of gray cast iron was 0.331. In the case of the sprayed disc Al-bronze powder showed the most excellent frictional characteristics . 4. Amount of burnish quantity obtained from burnish test by dynamometer is as follows : the sprayed disc with Al-powder was 1.079 mm : the sprayed disc with Al-bronze powder was 0.155 mm : the sprayed disc with Mo powder was 0.253 mm : the non-sprayed disc of gray cast iron was 0.241 mm. Al-bronze powder also showed the most excellent burnish characteristics.

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A Study on the Development of a Control and Monitoring System for Impressed Current Corrosion Protection (선박용 차세대 외부전원방식 제어 및 감시 시스템 UNIT 개발)

  • Kim, Y.B.;Kim, B.Y.;Suh, J.H.;Kim, J.W.
    • Journal of Power System Engineering
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    • v.10 no.2
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    • pp.104-110
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    • 2006
  • Corrosion has been around for all of recorded history. Cathodic protection is the electrical solution to the corrosion problem. Corrosion is not exactly a new topic. It has been around since the beginning of time. Corrosion is simply the loss of material resulting from current leaving a metal, following through a medium, and returning to the metal at a different point. Corrosion takes many forms and has various names, such as oxidation, rust, chemical, and bacteria action. Regardless of the agent, all corrosion is the result of electrical current flow. Various methods are used to treat corrosion or to try to prevent ti. Some of these include chemical treatment. coatings, and electrical current. Especially, proper impressed current can stop corrosive action on the protected surface. In this article, we introduce the Impressed Current Cathodic Protection (ICCP) Control and monitoring system developed by ourselves. The ICCP system is composed of a power supply, anode, reference electrode and controller. The main issue is to control the current flow on the desired value such that it is possible to force a metal to be more negative(cathodic) than the natural state. From the this process, we can achieve the cathodic protection. Of course, in the developed system, the necessary functions are possessed, such as remote control, monitoring of system fault detection etc. Some experimental results show the system performance and usefulness.

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Development of New Cultivar 'Millock' in Zoysiagrass (한국잔디 신품종 '밀록' 개발)

  • Choi, Joon-Soo;Yang, Geun-Mo
    • Asian Journal of Turfgrass Science
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    • v.20 no.1
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    • pp.1-10
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    • 2006
  • This study was carried out to develope new zoysiagrass cultivar 'Millock'(Patent registration No. : 10-2005-0110051). Artificial selfing of collected line of MJ8 was conducted to develope F1 plant (MJ8S). Among the inbred progenies, MJ8S-9 (Millock) showed superior performance in color, density, and rust resistance. 'Millock' showed genetically dark green color, with medium-textured leaf ($4.2{\pm}0.44$ mm), short internode length ($3.5{\pm}0.28$ cm), and wide leaf angle ($52.5{\pm}10.8$ degree). Height to the lowest leaf blade of this cultivar was $1.9{\pm}0.91$ cm, which may allow low mowing height. 'Millock' has a yellowish green stolen. Also, specific bands with primer number OPB 8 by RAPD analysis can be used for a cultivar identification.

Initial Stage of Atmospheric Corrosion of Carbon and Weathering Steels in Thailand Climate

  • Nii, K.;Bhamornsut, C.;Chotimongkol, L.;Vutivat, E.;Nakkhuntod, R.;Jeenkhajohn, P.;Suphonlai, S.
    • Corrosion Science and Technology
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    • v.2 no.4
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    • pp.183-188
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    • 2003
  • Corrosion of carbon and weathering steels were evaluated under 3 environmental exposures in Thailand (urban, rural and marine) for a year. The seasonal study was designed to determine different corrosion mechanisms by 6 months of dry season and 6 months of rainy season in a year. The sheltered exposure racks were used to determine the washing effect of min. At each site, climatic and pollutants analyses were carried out. The present study showed that the difference in corrosion rates of carbon and weathering steels was not so distinguished in both rural (AIT) and urban (TISTR) environments. The corrosion rate of weathering steel was somewhat lower than that of carbon steel and the decreasing tendency of corrosion rate with time was slightly higher for weathering steel than for carbon steel. In marine (Rayong) environment, the corrosion rate was higher and the effect of wet and dry seasons was observed. The corrosion rate in 6 dry months was higher for direct exposure than for sheltered exposure. However, in 6 rainy months. the corrosion rate of sheltered exposure was higher than that of direct exposure. In direct exposure for I year, that is, the first 6 dry months and the next 6 rainy months, the corrosion rate decreased with time. but in sheltered exposure, the corrosion rate did not decrease with time. instead, increased in the next 6 rainy months. This indicated that the protect ive layer formed in the first 6 dry months could be destroyed by high deposition of chloride to r sheltered exposure in the next 6 rainy months; whereas the rust layer for direct exposure could be kept sound due to washing effect in rainy season, even though the deposition rate of chloride was almost the same for direct and sheltered exposures. In marine environment, the weathering steel showed higher corrosion resistance than carbon steel but its corrosion rate was higher than those in other environments.

Development of the High-quality Coating System for the Steam Pipe of Ship (선박 스팀파이프용의 고내구성 도장 사양 개발 연구)

  • Lee, Sung-Kyun;Baek, Kwang-Ki;Hwang, Dong-Un;Song, Eun-Ha
    • Special Issue of the Society of Naval Architects of Korea
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    • 2006.09a
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    • pp.46-52
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    • 2006
  • For ships, heat resistant coating is applied on the aluminized steel pipe systems dealing with high temperature steam over $200^{\circ}C$. The coatings on these steam pipes should retain both heat resistance and anti-corrosion properties to provide long-term resistance against coating defects (rust, delamination and crack) under the harsh outdoor environment including repeated seawater wetting and condensation. Thus, it is important to improve the coating qualities and to reduce maintenance works for these steam pipe systems. In this study, five different commercial heat resistant coatings (A, B, C, D, E) were selected for evaluation. Various physical properties of these coatings were evaluated on the coatings applied on the aluminized steam pipes. FT-IR analysis was also employed to identify the factors contributing the degree of heat resistance and durability of each coating material. The results indicated that the heat resistance capacity of coatings increased with the increase of silicon content as well as the decrease of substituent content. Both products C and D showed the best coating qualifies, which can be standard coating systems for future steam pipe areas.

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Corrosion Resistance of Non-Chrome Magni 565 Coating and Characteristics of Its Coating Film (Non-Chrome Magni 565 코팅 피막의 특성과 내식성)

  • Kim, Sang-Su;Jeong, Byeong-Ho;Mun, Myeong-Jun;Kim, Mu-Gil
    • Journal of the Korean Society for Heat Treatment
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    • v.19 no.4
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    • pp.200-207
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    • 2006
  • In addition to the basic properties of the base and top coating agents, corrosion resistance of non-chrome magni 565 coating and characteristics of coating film when coated to steel substrate were studied. The system had a good wettability at room temperature. Moreover, both the contact angle and surface tension were affected little by the viscosity of coating agent and surface roughness of the steel substrate. And the samples coated with optimal conditions showed a great corrosion resistance in salt spray test with 1500 hours or longer of initial appearance time of rust. The coating film was composed of overlapping layer of zinc and aluminium flakes, and the thickness of base coat increased with an increase of base coat viscosity. Based on the C-F peaks of 1,1-Difluoroethaen homo-polymer, it was thought that the base coat was an inorganic polymer bond layer. Meanwhile, the top coat showed C-F peaks of polytetrafluoroethylene with C-H peaks of phenol in FT-IR analysis. From the lower weight loss of base coat in TG analysis, it was thought that cross linking density of base coat was larger than that of top coat. It was thought that the small exothermic reactions observed in DSC curves were due to the thermosetting resins contained in the coating agents. Compared to the non-coated specimen, the coated sample showed more higher polarization resistance and corrosion potential with lower corrosion current density.

New Yellow Single Chrysanthemum 'My Sun' for Pot Plant (분화용 국화 노랑색 홑꽃 'My Sun' 육성)

  • Jung, Yun-Kyung;Lim, Jae-Wook;Lee, Sang-Deok
    • Horticultural Science & Technology
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    • v.30 no.3
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    • pp.325-328
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    • 2012
  • A new Dendranthema grandiflourm 'My Sun' was developed at Gyeonggi-do Agricultural Research & Extension Services (GARES), Korea in 2009. 'My Sun' was initially derived from the cross in 2005 between 'Omega Time Orange', a potted chrysanthemum cultivar with orange single type, and 'Tasman', a potted chrysanthemum cultivar with white single type in 2005. The cultivar has single type flowers with yellow petals. Trial and evaluation was conducted from 2006 to 2009 for the selection of this variety, including a shading culture in spring and a retarding culture in winter. The flowering time of 'My Sun' was October 13th, and year-round flowering is possible by shading or lighting treatment. The diameter of flower is 21.0 mm. Numbers of flowers per stem and petals per flower are 34.4 and 20.4, respectively. Its leaf color was green (Green Group 137A) and plant height was 13.3 cm. Days to flowering under the short day treatment is about 42 in spring, and numbers of branch per plant was 3.4 ea in the winter. This cultivar was resistance to white rust and consumer's preference of new pot-mum is high level than control.

A Detail Investigation of Major Diseases Occurrence and Pathogen Population on Turfgrass Cultivation in Nationwide (국내 잔디 재배지 주요 병해 발생 및 병원균 밀도 조사)

  • Min, Gyu Young;Lee, Jung Han;Kwak, Youn-Sig
    • Weed & Turfgrass Science
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    • v.3 no.2
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    • pp.121-129
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    • 2014
  • We investigated turfgrass diseases and inoculum density at nationwide turfgrass cultivation sites in year of 2013. Occurrences of large patch and rust disease appeared in September. Brown patch recorded in September to October at Namhea and Pythium blight disease occurred outbreaks in early July at Namhea site. Some sites in Namhea damaged 3% area of total cultivation field by Sclerotinia homoeocarp. In Daepyeong (Gyeongnam), Fairy ring and large patch were recorded. Severe takeall and fairy ring have been observed in Gochang-si. Multi-site in Cheongju-si, brown patch was observed in pandemic level. Interesting enough, a cool-season turfgrass cultivate sites in Pyeongtaek-si brown patch, leaf blast, summer patch, and Curvularia leaf spot were investigated during the surveys period. Inoculum densities (Rhizoctonia spp.) at turfgrass cultivations sites were increased as cumulatively in all survey sites. The investigation result indicated that the disease occurrence and pathogens are similar as diseases in golf courses.

The Effect of Luxury Fashion Brand Customer Equity Drivers on Customer Loyalty - Differences among Segmented Markets based on Purchasing Patterns - (럭셔리 패션 브랜드의 고객자산 구성요소가고객충성도에 미치는 영향 - 럭셔리 패션 제품 구매빈도와 구매액에 따른 세분시장별 분석 -)

  • Hwang, Yookyung
    • Fashion & Textile Research Journal
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    • v.15 no.2
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    • pp.219-230
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    • 2013
  • To generate future profits, luxury brands need to recognize and understand customers as individually important and analyze the impact factors that improve specific customer equity. With the growing recognition that customer equity is a key strategic asset, this study empirically investigates the effect of customer equity drivers on customer loyalty based on the study of Vogel et al.(2008) which expanded the Rust et al.(2000)'s study on customer equity. We empirically examine if the customer equity drivers have a different impact on customer loyalty. This study hypothesizes that the relative effect of customer equity drivers would be different depending on the purchasing behavior of consumers and examines the effects of them on the relationship of the drivers of customer equity and customer loyalty. We use stepwise multiple regression analysis to empirically test the relationship of value equity, brand equity, and relationship equity and customer loyalty. Relationship equity influences customer loyalty more strongly than value equity and brand equity. Customers seem to build loyalty based on the careful assessment of all costumer equity drivers (value equity, brand equity, and relationship equity). In addition, their relative impact is different depending on the purchasing behavior of consumers. A company cannot maintain all customer equity drivers at a high level with limited marketing resources; therefore, marketing investment for all customer equity drivers need to be allocated differentially depending on the purchasing behavior of consumers.