• 한국세라믹학회지
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• 제29권7호
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• pp.577-585
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• 1992

TiB2 and TiC were prepared from the mixture of metal titanium, boron and graphite powders in Argon atmosphere by Self-propagating High-temperature Synthesis method. The sintered properties of TiB2-TiC composite as a function of TiC content and sintering temperature were investigated in TiB2 matrix. The sintered properties were the most excellent at 10 wt% TiC content in TiB2-TiC composite. The relative density, M.O.R strength, hardness and fracture toughness of TiB2-10 wt% TiC composite sintered at 190$0^{\circ}C$ for 90 min by hot-pressing under the pressure of 30 MPa were 98.6%, 634 MPa, 2128.1 kg/$\textrm{mm}^2$ and 4.09 MN/m3/2, respectively.

• 수산해양기술연구
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• 제30권4호
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• pp.350-356
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• 1994

We have prepared superconducting Bi-Pb-Sr-Ca.Cu-O thin films by RF magnetron sputtering technique, on heated MgO(100) substrates. Sputtering was carried out in a mixture of argon and oxygen(10%) and the pressure was maintained at 5 mTorr during deposition. The substrate temperature was maintained $400^{\circ}C$ during deposition. The films sputtered were amorphous and insulating. All the films became superconducting by annealing, The films annealed at $880^{\circ}C$ for 30 minutes in air showed high-Tc phase with zero resistivity of 93K. These results indicate that the growth of the high-Tc phase is promoted by the presence of Pb at annealing temperature.

• 시스템엔지니어링워크숍
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• 통권1호
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• pp.65-68
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• 2003

The air separation plants in the POSCO's Gwangyang Steel Works require high standard on quality as well as reliability as they have to continuously supply essential utility gases as oxygen, nitrogen and argon. And the plants are in the category of high pressure gas systems by the regulatory guidelines, which signifies that they have to maintain utmost level of safety. As an effort to systematically understand and calculate the risk potentials in the air separation plants, risk assessments have been performed on a phased approach: qualitative and followed by quantitative POSCO has chosen to use hazard and operability study and fault tree analysis to satisfy the requirement. As a result, the risk assessment team has identified number of safety and operability related findings. With importance of each and ever findings calculated, a priority list for what/when to do for them could have been presented on a balance fashion.

• Bulletin of the Korean Chemical Society
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• 제21권5호
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• pp.487-492
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• 2000

The combustion characteristics of a mixture of acetaldehyde, oxygen and argon behind a reflected shock wave at temperatures ranging from 1320 to 1897 K at 100 torr were studied. The emission from the OH radical at 306.4 nm and the pressure profile behind the reflected shock were measured to monitor ignition delay time. The ignition delay times were computed from a proposed mechanism of 110 elementary reactions involving 34 species. The simulation and sensitivity analysis confirm that the main channel for oxidation of acetaldehyde at high temperature consists of the Rice-herzfeld mechanism, the decomposition and oxidation of HCO, and the reaction of H with $O_2$.

• Korean Chemical Engineering Research
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• 제49권6호
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• pp.835-839
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• 2011

토치형 상압 플라즈마 반응기를 통한 방전 및 플라즈마 flame에 대한 분석과 발생된 플라즈마 현상을 이용하여 E. coli에 대한 살균효과를 측정하였다. 상압 플라즈마 반응기를 통해 나오는 플라즈마 flame의 길이는 입력전압, 반응기의 유량 그리고 아르곤/산소 혼합기체에서의 산소비율에 영향을 크게 받았다. 플라즈마 flame에 의한 가열효과는 10분 조사 후에도 $43^{\circ}C$ 미만으로 저온처리가 가능했다. E. coli에 대한 살균처리에서 입력전압의 증가, 아르곤/산소 혼합기체에서의 산소비율 증가 그리고 플라즈마 flame에 대한 노출시간의 증가에 따라 전체적인 살균효과를 향상되었다. 플라즈마 처리 시에 오존농도가 높은 공정조건에서 플라즈마 flame의 직접적인 접촉시간을 증가시키면 살균효과를 극대화할 수 있다.

• 전기학회논문지P
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• 제59권4호
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• pp.417-422
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• 2010

Atmosphere Plasma of Gas Discharge (APGD) has been used in plasma sources for material processing such as etching, deposition, surface modification and so on due to having no thermal damages. The APGD researches on AC source with high frequency have been mainly processed. However, DC APGD studies have been not. In order to understand APGD further, it is necessary to study on fundamental properties of DC APGD. In this paper, we developed a one-dimensional fluid simulation model with capacitively coupled plasma chamber at the atmosphere pressure (760 [Torr]). Nine kinds of Ar discharge particles such as electron (e), positive ions ($Ar^+$, $Ar_2^+$) and neutral particles ($Ar_m^*$, $Ar_r^*$, $Ar_h^*$, $Ar_2^*$(1), $Ar_2^*$(3) and Ar gas) are considered in the computation. The simulation was worked at the current range of 1~15 [mA]. The characteristics of voltage-current were calculated and the structure of Joule heating were discussed. The spatial distributions of Ar DC APGD and the mechanism of power consumption were also investigated.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2009년도 춘계 종합학술대회 논문집
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• pp.807-809
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• 2009

압전성을 갖는 산화아연 박막을 스퍼터링을 이용하여 실리콘 기판위에 증착하였고 여러 증착 공정변수들이 물성에 미치는 영향과 박막의 구조적 특성 및 전파경계조건을 고찰하였다. 특히, 평탄한 표면을 갖는 압전 박막을 제조하여 전파 특성에 우수한 증착조건을 제시하고 탄성표면파의 전파및 경계조건을 분석한다. 박막의 구조적 특성 분석을 위하여 여러가지 증착조건 중 아르곤과 산소의 가스비율 과 기판온도가 박막의 제조에 미치는 특성을 분석하였다. 스퍼터링 가스인 산소양이 50%이상으로 증가할수록 박막의 표면 거칠기가 나빠지는 특성을 보였다. 비저항과 표면형상은 유입되는 산소에 큰 영향을 받는다는 것을 알 수 있었다.

• 한국전기전자재료학회논문지
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• 제18권3호
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• pp.253-258
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• 2005

This paper presents characteristics of CrOx thin-film, which were deposited on $Al_2$O$_3$ wafer by DC reactive magnetron sputtering in an argon-oxide atmosphere for high temperature applications. The present paper deals with a study of the technological characteristics of thin film resistors to provide a control in obtaining temperature coefficients of resistance of given value. The optimized condition of CrOx thin-film were thickness range of 2500 $\AA$ and annealing condition(350 $^{\circ}C$, 1 hr) in oxide partial pressure(3.5${\times}$10$^{-4}$ torr). Under optimum conditions, the CrOx thin-films is obtained a high resistivity, p=340 $\mu$Ωcm, a low temperature coefficient of resistance, TCR=-55 ppm/$^{\circ}C$. The CrOx thin films resistors which were fabricated in this paper had excellent characteristics as high precision resistors.

• 센서학회지
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• 제14권1호
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• pp.56-61
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• 2005

This paper present characteristics of chromium oxide thin-film as piezoresistive sensors, which were deposited on Si substrates by DC reactive magnetron sputtering in an argon-Oxide atmosphere for high temperature applications. The chemical composition, physical and electrical properties and thermal stability ranges of the $CrO_{x}$ sensing elements have studied. $CrO_{x}$ thin films with a linear gauge factor(GF${\fallingdotseq}$15), high electrical resistivity (${\rho}$ = $340{\mu}{\Omega}cm$) and TCR<-55 ppm/$^{\circ}C$ have been obtained. These $CrO_{x}$ thin films may allow high temperature pressure sensor miniaturization to be achieved.

• 한국초전도ㆍ저온공학회논문지
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• 제6권3호
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• pp.27-32
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• 2004

High temperature superconducting coated conductor has a structure of /< superconducting layer>//. The buffer layer consists of multi layer, and the architecture most widely used in RABiTS approach is CeO$_2$(cap layer)/YSZ(diffusion barrier layer)/CeO$_2$(seed layer). Evaporation technique is used for the CeO$_2$ layer and DC reactive sputtering technique is used for the YSZ layer, A chamber was set up specially for DC reactive sputtering, Detailed features are as following. A separator divided the chamber into two halves a sputtering chamber and a reaction chamber. The argon gas for sputtering target elements flows out of the cap of sputtering gun, and water vapor for reaction with depositing species spouts near the substrate. Turbo pump is connected with reaction chamber. High speed deposition of YSZ film could be achieved in the chamber. Detailed deposition conditions (temperature and partial pressure of reaction gas) were investigated for the rapid growth of high quality YSZ film.