• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 C
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• pp.1428-1430
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• 1996

Thin Silicon oxynitride(SiON) films have been chemically deposited using 193nm ArF Excimer Laser CVD, with $Si_{2}H_{8}$, $N_{2}O$, and $NH_3$ as the reactive gases and $N_2$ as the carrier gas. Experimental results show that deposition rate and refractive index have a strong dependence on substrate temperature, chamber pressure, gas ratio, laser power and laser beam height. Electrical characterization of oxynitride films demonstrates that for $NH_{3}/N_{2}O$ flow ratios ranging from 0.25 to 1, the leakage currents, the interface trap density and the capacitances (dielect ric constant) increase and the dielectric breakdown fields decrease

• 대한화학회지
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• 제56권2호
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• pp.228-235
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• 2012

$N_2O_2$계 시프염기 리간드인 N,N'-bis(4-methoxysalicylidene)phenylendiamine(4-$CH_3O$-salphen)을 합성하였다. 합성한 4-$CH_3O$-salphen을 이용하여 분광광도법으로 수용액 중의 Cu(II)이온 정량실험을 시도하였다. Cu(II)이온 정량을 위한 최적 실험조건을 구한 결과, 4-$CH_3O$-salphen 농도는 $2.0{\times}10^{-4}\;mol/L$, 용매 DMSO와 물의 비율은 50/50(v/v), pH는 5.5에서, 온도는 $55^{\circ}C$에서 한 시간정도를 물중탕하고, 시료의 흡광도는 388 nm였고, 그 조건에서 검량곡선을 작성하였다. 작성된 검량곡선(${\varepsilon}=3.6{\times}10^4\;mol^{-1}cm^{-1}$)은 $R^2$=0.9963의 상관계수 값을 나타내었다. 이상의 최적화된 실험조건을 이용하여 온천수, 반도체 공장폐수 및 하수 처리장의 처리수를 채취하여 Cu(II)이온을 각각 정량 분석한 결과는 측정 평균값이 기준 값에 대하여 0.6~5.4% 범위에서 잘 일치 하였고, 정량한계는 31.77 ng/mL($5.0{\times}10^{-7}\;mol/L$)이었다.

• 해양환경안전학회지
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• 제21권2호
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• pp.188-193
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• 2015

일반적으로 선박용 디젤엔진의 아산화질소($N_2O$)배출률은 이산화황($SO_2$)배출률과 밀접한 상관성을 갖고 있고, 선박에서 사용되는 연료의 다양성은 $N_2O$배출특성에 영향을 미친다고 받아들여져 왔다. 최근의 연구보고에 의하면 연료 연소에서 발생한 충분한 일산화질소(NO)가 존재할 경우, 배기의 $SO_2$배출률이 $N_2O$생성에 미치는 영향은 NO의 영향보다 막대하게 크다. 그러므로 $SO_2$성분으로부터 기인하는 $N_2O$생성은 NOx저감을 위한 배기가스 재순환(EGR) 시스템에서 중요한 인자로 작용한다. 본 실험적인 연구의 목적은 $SO_2$유량 증가를 갖는 디젤엔진의 흡기가 배기의 $N_2O$배출률에 미치는 영향에 대하여 조사하는 것이다. 실험에 사용된 테스트 엔진은 2600rpm에서 12kW의 출력을 갖는 4행정 직접분사식 디젤엔진이고, 운전조건은 75% 부하에서 실시되었다. 0.499%($m^3/m^3$)의 $SO_2$표준가스는 흡기의 $SO_2$농도를 변화시키기 위해 사용되었다. 결과적으로 황 성분을 포함하지 않는 연료는 $SO_2$를 배출시키지 않았고, 흡기 중에 $SO_2$표준가스의 증가에 따른 배기의 $SO_2$배출률은 $SO_2$흡입률과 비교하여 거의 같은 비율이었다. 또한, 흡기의 $SO_2$유량 상승은 $N_2O$배출률을 상승시켜 배기 중의 $N_2O$는 흡기의 $SO_2$혼합기에 의해 생성되었다. 결국 황 성분을 함유한 연료는 연소 중에 $SO_2$를 형성하고 배기 중의 $N_2O$는 연소실에 존재하는 NO와 $SO_2$의 반응에 의해 발생된다고 할 수 있다.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2014년도 제49회 KOSCO SYMPOSIUM 초록집
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• pp.245-248
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• 2014

• 한국전기전자재료학회논문지
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• 제15권5호
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• pp.383-387
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• 2002

N-channel metal-ferroelectric-insulator-semiconductor field-effect-transistors (MFISFET's) by using $SrBi_2Ta_2O_9$/Silicon Nitride/Si (100) structure were fabricated. The fabricated devices exhibit comfortable memory windows, fast switching speeds, good fatigue resistances, and long retention times that are suitable for advanced ferroelectric memory applications. The estimated switching time and polarization ($2P_r$) of the fabricated FET measured at applied electric field of 376 kV/cm were less than 50 ns and about 1.5 uC/$\textrm{cm}^2$, respectively. The magnitude of on/off ratio indicating the stored information performance was maintained more than 3 orders until 3 days at room temperature. The $I_DV_G$ characteristics before and after being subjected to $10^11$ cycles of fatigue at a frequency of 1 MHz remained almost the same except a little distortion in off state.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.283-283
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• 2007

Titanium nitride thin films were deposited on $SiO_2$/Si substrate by rf-reactive magnetron sputtering. The structural and electrical properties of the films were investigated with various $N_2/(Ar+N_2)$ flow ratios (nitrogen/argon flow ratio). The resistivity as well as temperature coefficient of resistance (TCR) of the films strongly depends on phase structure. For the films deposited at nitrogen/argon flow ratio of below 5%, the resistivity increased with increasing nitrogen/argon flow ratios. However, the resistivity of the film deposited at nitrogen/argon flow ratio of 7% decreased drastically; it is even smaller than that of metal titanium nitride. A near-zero TCR value of approximately 9 ppm/K was observed for films deposited at nitrogen/argon flow ratio of 3%.

• 한국토양비료학회지
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• 제45권5호
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• pp.733-737
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• 2012

The objectives of this study were to investigate soil chemical properties for forest rehabilitation and suggest design and management in abandoned coal mine areas in Mungyeong, Gyeongsangbuk-do. Total study sites were 10 sites, and soil analysis particular were soil pH, TOC, total-N, C/N ratio, A.v. $P_2O_5$, and CEC. Because most of study sites showed soil pH from 5.0 to 7.0, it seems that soil pH does not affect growth of vegetation. But soil pH in Danbong1 was acidic (pH 4.6), so it is needed to improve with ameliorant such as limestone. Most of study sites is necessary to manage for organic matter and Nitrogen, because there sites showed lower value of TOC and total-N than general forest. The values of A.v. $P_2O_5$ and CEC were good in most of study sites, so it seems that they do not have effect on vegetation growth. All of soil factors has no regression according to elapsed time after rehabilitation. TOC, total-N and A.v. $P_2O_5$ among soil properties have positive relationship between each other. It is necessary to fertilizer for organic matter and Nitroge because of value in TOC, total-N and C/N ratio. The results of this study were analyzed only one time. So, long-term monitoring for soil properties is important for the correct forest rehabilitation and management.

• Tribology and Lubricants
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• 제18권3호
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• pp.228-234
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• 2002

Generally, space structures are subjected to severe situations, such as, sublimation, strong evaporation of lubricants, thermal stresses, high temperature gradients, irradiation, impacts by microscopic meteorites, and other factors. Recent]y, various kinds of coatings are applied to the parts under heavy contact stresses, in order to insure long wear-free lives and/or reduce friction coefficients. In space structures, molybdenum disulfide is using frequently. Moreover TiN, Al$_2$O$_3$, PTFE(Poly Tetra Fluor Ethylene) are introduced recently for space structure. In this part we are going to apply the partial model method, developed in reference[11] to analyze part with coated layer. In referencer[l1], we compute the reasonable size of partial model and aspect ratio. Using these data, we analyze the structures coated with TiN, Al$_2$O$_3$, PTFE under contact load, temperature and crack model . Beside, we consider the stress analysis under time dependent load and transient thermal effect.

• E2M - 전기 전자와 첨단 소재
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• 제7권5호
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• pp.403-408
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• 1994

Dielectric and structural properties of $Ba_{1-x}$(Z $n_{1}$3/T $a_{2}$3/) $O_{3}$+1 mol% Mn $O_{2}$ (x=0, 0.01, 0.02, 0.03, 0.04) ceramics was investigated at microwave frequencies. With $Ba_{+2}$ shortage, the sinterability and the unloaded Q( $Q_{u}$) were much improved, and the ordering in B site and the lattice distortion was greatly enhanced and the structure approached the completely ordered structure. $Q_{u}$ was strongly correlated with these factors such as ordering ratio, lattice distortion and sinterability, and had the maximum value of 7500 at x=0.01. The dielectric constant was near 30 and the temperature coefficient of the resonant frequency was 2 ppm/.deg. C at x=0.01.1.1.1.

• 한국자동차공학회논문집
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• 제5권2호
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• pp.60-68
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• 1997

Rayleigh Scattering Cross Sections($\sigma$i) of various gases and the temperature distributions of premixes C3H8/O2 flame are measured by high power KrF(248nm) Exci- mer laser and ICCD camera. Results show that $\sigma$i of O2 and Propane(C3H8) gases agree well in the 5% error range, but of H2 has the more or less difference from the calcul- ated value by other groups. This is attributed to the low RS signal of H2 to Nosie level(S/N ratio). The temperature distributions of flame range out between 300K in the air and about 2000K in the burned area. In this temperature range, out system has the about 250K temperature resolution. Because low RS signals in the reaction area with high temperature are affected highly by noises, temperature uncertainty of this area is relatively high to another part of flame. Experimental results show that UV Rayleigh Scattering can be used for the measurement of mixing ratio of mixed gases and the temperature distributions of flame. Especially, this technique can be applied for the measurement of the mixing ratio of air/fuel before the ignition and the flame structure after the ignition inside the Engine.