• 제목/요약/키워드: base material

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$CF_4$ 분해에 미치는 비열플라즈마 반응기 구조의 영향 (Effect of Non-thermal plasma Reactor construction by $CF_4$ decomposition)

  • 김선호;박재윤;하현진;황보국;김광수;임근회
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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    • pp.912-916
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    • 2002
  • In this paper, the $CF_4$ decomposition rate and by-product were investigated for a simulated two plasma reactors which are metal particle reactor and spiral wire reactor as function of mixed gases. The $CF_4$ decomposition rate by plasma reactor with metal particle electrode had a gain of 20~25[%] over that by plasma reactor with spiral wire electrode. The $CF_4$ decomposition efficiency increases with increasing applied voltage up to the critical voltage for spark formation. The $CF_4$ decomposition efficiency of metal particle reactor was about 80[%] at AC 24[kV]. The $CF_4$ decomposition rate used $Ar-N_2$ as base gas was the highest among three base gases of $N_2$, $Ar-N_2$, air. The by-products of the $N_2$, $Ar-N_2$ base as were similar, but in case of air base they were different.

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Biofilm formation on denture base resin including ZnO, CaO, and TiO2 nanoparticles

  • Anwander, Melissa;Rosentritt, Martin;Schneider-Feyrer, Sibylle;Hahnel, Sebastian
    • The Journal of Advanced Prosthodontics
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    • 제9권6호
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    • pp.482-485
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    • 2017
  • PURPOSE. This laboratory study aimed to investigate the effect of doping an acrylic denture base resin material with nanoparticles of ZnO, CaO, and $TiO_2$ on biofilm formation. MATERIALS AND METHODS. Standardized specimens of a commercially available cold-curing acrylic denture base resin material were doped with 0.1, 0.2, 0.4, or 0.8 wt% commercially available ZnO, CaO, and $TiO_2$ nanopowder. Energy dispersive X-ray spectroscopy (EDX) was used to identify the availability of the nanoparticles on the surface of the modified specimens. Surface roughness was determined by employing a profilometric approach; biofilm formation was simulated using a monospecies Candida albicans biofilm model and a multispecies biofilm model including C. albicans, Actinomyces naeslundii, and Streptococcus gordonii. Relative viable biomass was determined after 20 hours and 44 hours using a MTT-based approach. RESULTS. No statistically significant disparities were identified among the various materials regarding surface roughness and relative viable biomass. CONCLUSION. The results indicate that doping denture base resin materials with commercially available ZnO, CaO, or $TiO_2$ nanopowders do not inhibit biofilm formation on their surface. Further studies might address the impact of varying particle sizes as well as increasing the fraction of nanoparticles mixed into the acrylic resin matrix.

비 마약성진통제 0.3% DA-5018 cream의 피부 1차 자극성 및 안점막 자극성 시험 (Primary Skin and Eye Irritation Test of 0.3% DA-5018 Cream, a New Non-narcotic Analgesic)

  • 김옥진;김동환;강경구;백남기;김원배;양중익
    • Biomolecules & Therapeutics
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    • 제4권4호
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    • pp.364-372
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    • 1996
  • The primary skin and eye irritation test of 0.3% DA-5018 cream, a capsaicin analogue, were carried out in rabbits. As control materials, Zostrix-HP cream (0.075% capsaicin cream) and the base of 0.3% DA-5018 cream were used in the same manners. In the primary skin irritation test, the Primary Irritation Index (P.I.I.) was 1.6, 1.9 and 0.5 in groups treated with 0.3% DA-5018 cream, Zostrix-HP cream and the base of 0.3% DA-5018 cream, respectively. The irritation ratings of 0.3% DA-5018 cream and Zostrix-HP cream were mildly irritating. The base of 0.3% DA-5018 cream was evaluated as a non-irritating material. In the eye irritation test, 0.3% DA-5018 cream and Zostrix-HP cream could be considered as mildly irritating materials. But, the base of 0.3% DA-5018 cream was a non-irritating material. These results suggest that 0.3% DA-5018 cream has mildly irritating activity and its irritancy is similar to that of Zostrix-HP cream.

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고효율 단결정 태양전지 설계를 위한 PC1D 시뮬레이션 (PC1D Simulation for Design High Efficiency Single Crystaline Solar Cell)

  • 정성현;이영석;문인용;이준신
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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    • pp.136-137
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    • 2008
  • 태양전지의 효율은 실리콘 자체의 특성에 의해서 결정 되거나 완성된 실리콘을 통해 태양전지를 제조하는 과정에서 Texturing, Coating 등을 통해 효율을 변화 시킬 수 있다. PC1D를 이용해 Texturing, Base Resistivity, Emitter Doping등을 조절해가며 고효율 태양전지를 위한 시뮬레이션을 하였다. Texture Angle이 $80^{\circ}$, Texture Depth가 2um, Base Resistivity가 0.2[${\Omega}{\cdot}cm$], Emitter Doping이 8*Exp(19)[$cm^{-3}$]일 경우 효율이 19.9%로 최적화 되었다.

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그라우트재의 침투특성 및 내구성 규명 (A Searchig Examination of The Permeability and Durability of Grouting)

  • 김찬기;김중철;김용철;차경섭;김선주
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2010년도 추계 학술발표회
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    • pp.533-538
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    • 2010
  • This study was performed for evaluate permeability in base of development material and existing grouting. And examined durability by age strength when devide seawater and fresh water that water curing. Executed permeability test to choose base to produce pouring in specimen. About 5 grouting material, produced pouring in specimen. Seawater strength of all grouting materials except BGI decreased gradually as result that divide seawater and fresh water that water curing.

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마이크로 가스센서의 열적 성능에 관한 연구 (A Study of Thermal Performances for Micro Gas Sensor)

  • 주영철;김창교
    • 대한기계학회논문집B
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    • 제30권6호
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    • pp.531-537
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    • 2006
  • A lever type $NO_2$ micro gas sensor was fabricated by MEMS technology. In order to heat up the gas sensing material to a target temperature, a micro heater was built on the gas sensor. The sensing material laid on the heater and electrodes and did not contact with the silicon base to minimize the heat loss to the silicon base. The electric power to heat up the gas sensor to a target temperature was measured. The temperature distribution of micro gas sensor was analyzed by a CFD program. The predicted electric power of micro heater to heat up the sensing material to the target temperature showed a good agreement with the measured data. The design of micro gas sensor could be modified to show more uniform temperature distribution and to consume less electric power by optimizing the layout of micro heater and electrodes.

마이크로 핫플레이트를 갖는 마이크로 가스센서의 열적성능에 관한 연구 (A Study on Thermal Performances of Micro Gas Sensor with Micro Hotplate)

  • 주영철;임준형;이주헌;김창교
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제55권5호
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    • pp.278-285
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    • 2006
  • A micro hotplate for micro gas sensor was fabricated by MEMS technology. In order to heat up the gas sensing material to a target temperature, a micro hotplate was built on the gas sensor. The sensing material was deposited on the heater and electrodes, and did not contact with the silicon base to minimize the heat loss to the silicon base. The electric power to heat up the gas sensor was measured. The temperature distribution of micro gas sensor was analyzed by a CFD program. The predicted electric power to heat up th sensing material showed a good agreement with the measured data. The design of micro gas sensor could be modified to increase the temperature uniformity and to decrease the electric power consumption by optimizing the layout of micro hotplate and electrodes.

Hard, Wear Resistant Metal Surfaces for Industrial Applications through Laser Powder Deposition

  • Sears, James;Costello, Aaron
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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    • pp.293-294
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    • 2006
  • Laser Powder Deposition (LPD) is a technology capable of modifying a metallic structure by adding the appropriate material to perform a desired function. LPD offers a unique fabrication technique that allows the use of soft (tough) materials as base structures. Through LPD a hard material can be applied to the base material with little thermal input (minimal dilution and heat-affected-zone {HAZ}), thus providing the function of a heat treatment or other surface modifications. These surface modifications have been evaluated through standard wear testing (ASTM G-65), surface hardness (Rc), micro-hardness (vickers), and optical microscopy.

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소결 마찰재의 마찰특성에 미치는 고체 윤활제의 영향 (The effect of solid lubricant on the frictional characteristics of Cu base sintered friction material.)

  • 정진현;이범주;조정환;정동윤;권석진
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 1996년도 제24회 춘계학술대회
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    • pp.45-54
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    • 1996
  • The effect of graphite on the frictional characteristics of Cu-based sintered friction materials was studied by pin-on-disk type wear test. A study has been carried out concerning the optimum concentration of graphite in sintered friction material to obtain the minimum wear rate and low friction coefficient . Friction coefficient and wear rate were increased as increasing the content of graphite in the matrix. In the study the optimum concentration of graphite was 19vol % to get the minimum wear rate and optimal frick'ion coefficient.

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철도차량 하부구조의 적정 용접조건에 관한 연구 (Study on Optimal Welding Conditions for Underframe of Railway Vehicles)

  • 정상호;김해지
    • 한국기계가공학회지
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    • 제20권4호
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    • pp.1-7
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    • 2021
  • In this study, MIG welding was performed on extruded 6005A-T6 material, which is used in the base panel of railway vehicles. The material was considered as the experimental base material, and argon shielding gas and ER5356 and ER4043 filler metals were used as the consumable welding materials. Welding coupons were prepared under various welding conditions by using an auto-welding system that various welding conditions applied 2.5Hz and 4.5Hz the pulse frequency of SynchroPuls function of welding machine and 1.0mm and 1.5mm of root face affect the weld penetration of welding joint. The welding current and voltage were also varied for this testing. On the basis of the results obtained, optimum welding conditions are proposed.