• Title/Summary/Keyword: Material property

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The Effect of Fcoidan Molecula Weight on Cosmetic Function (후코이단의 분자량이 화장품기능성에 미치는 영향)

  • Cha, Seong Han;Ahn, Myeong Won;Lee, Jung Shik;Kim, Young Suk;Kim, Dong-Uk;Byun, Tae Gang;Park, Kwon Pil
    • Korean Chemical Engineering Research
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    • v.50 no.4
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    • pp.604-609
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    • 2012
  • Properties of fucoidan used for functional cosmetic ingredients and the effect of fucoidan molecular weight on the cosmetic functions were studied. Fucoidan was extracted from Undaria pinnatifida sporophylls and molecular weight (35~160 kDa) of fucoidan was controlled by contact glow discharge electrolysis (CGDE). To test possibility of fucoidan as a cosmetics material, tyrosinase inhibition property, water-holding property, elastase activity inhibition property and DPPH free radical scavenging property were measured. Water-holding property of fucoidan was higher than that of hyaruronic acid, which is known as the one of the best water-holding material. The water-holding strength of fucoidan slightly increase as molecular weight of fucoidan decrease. Elastase activity inhibition (anti wrinkle effect) of fucoidan was higher than that of adenosine using standard material for anti wrinkle test. Optimum molecular weight of fucoidan to obtain highest tyrosin inhibition effect, elastase inhibition effect and radical scavenger effect is 100 kDa.

The U-type Model on Ag Doping effect in Amorphous Chalcogenide thin films (비정질 칼코게나이드박막으로서의 Ag 도핑효과에 대한 U-형 모델)

  • 김민수;이현용;정홍배
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1995.05a
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    • pp.50-53
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    • 1995
  • In this paper we have obtained property by considering the change of optical energy gap as a function of photo-does for exposing photo on Ag/a-Se$\sub$75/Ge$\sub$25/ thin films. This U-type property was obsered for all photo-exposing except for blu-pass filtered Hg lamep. Expecially, very large band shift(~0.3[eV]) is obtained by exposing He-Ne laser (6328[${\AA}$]). It is impossible to explain this property for exposing He-Ne and semiconductor laser through DWP model, which was explained for photo-exposing above the energy gap. Therefore we suggest a new modified model of DWP model for Ag/a-Se$\sub$75/Ge$\sub$25/ bilayer thin films.

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Effects of post-annealing treatment at various temperature on the light emission properties of ZnO thin films on sapphire (사파이어 기판 위에 증착된 ZnO 박막의 후열처리에 따른 발광특성 연구)

  • 강홍성;심은섭;강정석;김종훈;이상렬
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.07a
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    • pp.119-122
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    • 2001
  • ZnO thin films on (001) sapphire substrates have been deposited by pulsed laser deposition(PLD) technique at the oxygen pressure of 350 mTorr. In order to investigate the effect of post-annealing treatment with oxygenn pressure of 350 mTorr on the optical property of ZnO thin films, films have been annealed at various substrate temperatures after deposition. After post-annealing treatment in the oxygen ambient, the optical properties of the ZnO thin films were characterized by PL(Photoluminescence) and structural properties of the ZnO were characterized by XRD, and have investigated structural property and optical property for application of light emission device.

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A study on the Experiment of Basic Property of Concrete Using Recycled Fine Aggregate (재생잔골재를 사용한 콘크리트의 기초물성에 관한 실험적 연구)

  • 김재성;권인표;강석표;홍성윤
    • Proceedings of the Korea Concrete Institute Conference
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    • 2003.11a
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    • pp.116-119
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    • 2003
  • The Natural aggregate will be faced with serious shortage problem within 10 years due to the great amount of consumption in domestic. In order to reserve our natural resources, the construction waste has to be reused as an alternative material. Especially, It is more imminent to find alternative material in case of fine aggregate. This paper presents and experimental results on the fundamental property of concrete using recycled fine aggregate. As a result, it was found that the property of concrete using recycled fine aggregate substituted for 25% of a natural sand was similar in that of crushed fine aggregate.

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A Study on the Spacial Boundary in Sejima Kazuyo's Housing Architecture (세지마 가즈요의 주거건축에 나타나는 경계공간에 관한 연구)

  • Kim Hyoung-Jun
    • Journal of the Korean housing association
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    • v.17 no.1
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    • pp.37-45
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    • 2006
  • The purpose of this study is to explore the spacial boundary in Kazuyo Sejima's housing architecture, to give attention to contemporary housing architecture that we inhabit, and to escape from existing architectural concepts. This study seeks to the meaning and possibility of the spacial boundary on the basis of contemporary architecture. The spacial boundary can be studied in the aspect of architectural space that molds human experience and perception. As a result of this study, three properties in the spacial boundary are revealed. One property of the spacial boundary is soft that protect privacy from gaze of exterior. Another property is that communication that changes according to material of boundary and its experience of observer. The other property is to have uncertainty by compound of programs and material-mixing senses including its perception. This results means that the spacial boundary as interface which is represent our everyday life in the contemporary housing architecture.

The Mechanical and Electrical property changes of Overhead Conductor due to Forest Fire and Agents (산불과 소화약제에 노출된 가공송전선의 기계적 및 전기적 특성 변화)

  • Jang, Young-Ho;Kim, Byung-Geol;Kim, Shang-Shu;Han, Se-Won;Kim, Jin-Han
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.11a
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    • pp.459-460
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    • 2008
  • Forest Fire can cause a serious damage to overhead conductors. Therefore, the detailed investigation for the changes of mechanical and electrical properties of damaged conductors should be carried out to understand the effect of forest fires on conductors. This is very much important to maintain transmission line safely. Oxidation of overhead conductor was increased with temperature and time(maximum time : 30min). Conductivity of Al conductor was decreased by Agents. The detailed will be given in the text.

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Effect of Solvent Mixture Ratio on Rheology Property of Slurry and Thickness Control of Ceramic Green Sheets (유기 용매 혼합비에 따른 슬러리의 유동 특성과 세라믹 그린 쉬트의 두께 제어)

  • Kim, Jun-Young;Kim, Seung-Taek;Park, Jong-Chul;Yoo, Myong-Jae
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.21 no.3
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    • pp.236-241
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    • 2008
  • The effect of organic solvent mixture ratio on the rheology property of slurry and thickness control of ceramic green sheet was investigated. For selecting a suitable dispersant multiple light scattering method was used to evaluate the particle migration velocity and variation of clarification layer thickness. Using the selected dispersant the dispersion property of solution according to solvent mixture ratio was investigated. Binder and plasticizers were added to formulate slurries and their viscosity was evaluated according to solvent mixture ratio. Ceramic green sheets with average thickness of 30, 50 urn were fabricated via tape casting and their thickness tolerances measured. As a result according to solvent mixture ratio the solution and slurry properties varied and for the mixture ratio of ethanol/toluene of 80/20 the ceramic green sheet with the lowest thickness tolerance was obtained.

Reclaiming property of magnetic adsorbent for oil spill recovery and pollution control (환경오염방지 유출오일 회수용 자기흡착제의 재생회복 특성)

  • Soh, Dea-Wha;George, Ksandopulo;Lim, Byong-Jae;Nina, Mofa;Tlek, Ketegenov
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11b
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    • pp.296-299
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    • 2001
  • Data on the oil spill recovery from the water surface by light floating electromagnetic plants using a new magnetic adsorbent are given. The feasibility scope for further oil recovery from such gathered mixtures(oil + adsorbent), reuse of this magnetic adsorbent and its property reclaiming and recycling were shown. The basic conception of the oil spill recovery and efficiency of this method were set forth.

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Moisture Vapor Management Properties of Fabrics Determining Human Sensorial Comfort in Transient Conditions (동적 상태에서 주관적 착용감에 영향을 미치는 직물의 수증기상태의 수분전달 특성)

  • ;Roger L. Barker
    • Journal of the Korean Society of Clothing and Textiles
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    • v.24 no.7
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    • pp.1073-1080
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    • 2000
  • Moisture transfer property of fabrics has known as one of the most important factors deciding wearer's subjective comfort not only thermally but also of sensorial. As a decisive property of fabric materials in determining human sensorial comfort, moisture vapor management property of heat resistant workwear material was examined in terms of increasing and decreasing rate and maximum value of relative humidity in the microclimate under the sweat pulse situation. An unique moisture regulation index, B$_{d}$, was calculated from the measurements using a novel dynamic sweating hot plate apparatus and was used to assess the buffering capacity of fabrics against a moisture vapor sweat pulse.e.

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