• Title/Summary/Keyword: 표면강화

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Study on Surface Enhanced Raman Scattering of Indigo Carmine (lndigo Carmine의 표면증강라만스펙트럼에 관한 연구)

  • Lee, Chul Jae
    • The Journal of the Convergence on Culture Technology
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    • v.4 no.2
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    • pp.155-160
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    • 2018
  • In this study, the experiments for surface enhancement of silver mirror substrates were done, where we checked the characteristics of silver surface made by Tollen's and ${\gamma}$- irradiation method. The surface enhancement of Indigo carmine was analyzed by silver mirror and silver sol surfaces. The assignments of the vibrational bands shown in SERS spectra are given based on both literature and the semi-empirical calculations at the PM3 methods. We deduced that the adsorption orientation of Indigo carmine was little tilted perpendicular to the silver surfaces by using of the surface selection rules.

Fundamental Characteristics of Isometric Muscle Force Potentiation induced by Surface Stimulation in FES (기능적 표면 전기자극에 의해 유발되는 등척성 근력강화현상의 기초적 특성)

  • 엄광문
    • Journal of Biomedical Engineering Research
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    • v.22 no.2
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    • pp.151-156
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    • 2001
  • A computer model of the musculoskelotal system that provides accurate prediction of muscle force and body movement trom the stimulation input is desired for the effective control system design in FES. This paper aims to investigate the fundamental properties of the gradual muscle force potentiation that was not included in the previous muscle models, for future development of a model that provides vetter prediction of FES-induced muscle force and body movement. Specifically, hou the muscle length was investigated. The experimental results showed that both the force increment ratio and the time-to-peak during electrical stimulation decreased with stimulatino frequency. When the muscle potentiation state was saturated by preceding stimulation. the force did not increase any more during additive stimulation. Muscle length significantly affected the force potentiation in such a way that the force increment ratio decreased with muscle length. A new model of the muscle potentiation based on these results is desired in the future.

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Comparative studies on microstructure and mechanical properties of CrN, Cr-C-N and Cr-Mo-N coatings (CrN, Cr-C-N, Cr-Mo-N 박막의 미세구조와 기계적 성질에 관한 연구)

  • Lee, Jeong-Du;Lee, Gwang-Ho
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2009.05a
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    • pp.184-185
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    • 2009
  • 하이브리드 코팅 시스템을 이용하여 CrN 을 기초로 3성분계 코팅을 합성한다. 이번 연구는 C를 첨가한 음이온 고용경화와 Mo를 첨가한 양이온 고용경화의 영향이 미세구조와 기계적 성질에 미치는 영향을 알아보는 것이다. Cr-C-N 과 Cr-Mo-N 코팅은 23, 43GPa의 최대 경도 값을 가진다. 이 경도강화는 고용강화로 설명할 수 있다.

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Surface Temperature of Flooring Board Using Woodceramics with Sending an Electric Current (우드세라믹 통전에 의한 마루판의 표면온도 변화)

  • Oh, Seung-Won
    • Journal of agriculture & life science
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    • v.46 no.1
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    • pp.29-34
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    • 2012
  • To examine possibilities to make use of woodceramics for the lower material of hot-floored ondol boards, woodceramics made from sawdust board with Pinus densiflora, put them in a wood frame and concrete block and heated them sending an electric current, and measured changes in surface temperature of a laminated floor board and a plywood floor board. As the sending an electric current to time passed, their surface temperature increased rapidly up to 20 minutes, and then gradually ascended. In terms of the surface temperature in the wood frame, the beginning temperature of a plywood floor board was higher than that of laminated floor one; however, as time passed, a laminated floor board's temperature rose, and after 60 minutes, it showed similar to the temperature of a floor board of lamination. On the other hand, the surface temperature in a concrete block showed that the laminated floor board was higher than the plywood floor board in both early and 60-minute later temperatures. With the lapse of time after switching off, the surface temperature of floor boards slowly dwindled up to 9 minutes, and from that time on, began to drop sharply. In terms of the descent speed of surface temperature, when woodceramics' surface temperature was adjusted at $70^{\circ}C$, the laminated floor board was the highest; when it was at $80^{\circ}C$, the plywood floor board was the highest, resulting in rapid descent speed of heat.

Surface Characterization of Rocks after Treated with Developed Consolidants (개발 강화제 처리 전후의 암석 표면에 나타나는 특성 변화 연구)

  • Kim, Jeong-Jin;Jang, Yun-Deuk;Won, Jong-Ok;Kang, Young-Soo
    • Journal of the Mineralogical Society of Korea
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    • v.25 no.2
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    • pp.105-115
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    • 2012
  • The consolidants have been widely used for the consolidation of decaying heritage stone surfaces. In this study, X-ray diffraction analysis, polarized and stereo-microscope and scanning electron microscope were used to study the surface characterization of granite, sandstone and marble, and to assess the efficiency and the effects of the developed condolidants in the field. The developed consolidants used in this experiment are 100%1T1G and 3%40nm/97%1T1G. The effects of consolidants are 3%40nm/97%1T1G${\gg}$100%1T1G in granite, 3%40nm/97%1T1G>100%1T1G in sandstone, and 3%40nm/97% 1T1G=100%1T1G in marble. The characteristics of rock surface when treated with consolidants show different result according to consolidantes type. This result of treating with consolidant can be used for the conservation of an decaying heritage stone.

Effects of Electrochemical Oxidation of Carbon Fibers on Mechanical Interfacial Properties of Carbon Fibers-reinforced Polarized-Polypropylene Matrix Composites (전기화학적 산화처리가 탄소섬유/극성화된 폴리프로필렌 복합재의 기계적 계면 특성에 미치는 영향)

  • Kim, Hyun-Il;Choi, Woong-Ki;Oh, Sang-Yub;An, Kay-Hyeok;Kim, Byung-Joo
    • Applied Chemistry for Engineering
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    • v.24 no.5
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    • pp.476-482
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    • 2013
  • In this work, the effects of electrochemical oxidation of carbon fiber surfaces on mechanical interfacial properties of carbon fibers-reinforced polarized-polypropylene matrix composites were studied with various current densities during the treatments. Surface properties of the fibers before and after treatments were observed by SEM, AFM, XPS, and contact angle measurements. Mechanical interfacial properties of the composites were measured in terms of critical stress intensity factor ($K_{IC}$). From the results it was found that $O_{1s}$ peaks of the fiber surfaces were strengthened after electrochemical oxidation which led to the enhancement of surface free energy of the fiber, resulting in good mechanical performance of the composites. It can be concluded that electrochemical oxidation of the carbon fiber surfaces can control the interfacial adhesion between the carbon fibers and polarized-polypropylene in this composites system.