• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2001년도 춘계학술발표회 초록집
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• pp.73-73
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• 2001

Boron-containing materials have several excellent properties, such as superlnardness, insulation and non-Rinear optical property. Recently, oxynitride compounds, such as Si(ON), Ti(ON), became the promising materials applied in diffusion barrier layer and solar cell. With the expectation of obtaining the hybrid property, we have firstly grown the BON thin film by radio frequency (R.F.) plasma enhanced metalorganic chemical vapm deposition (PEMOCVD) with 100 kHz frequency and trimethyl borate precursor. The plasma source gases used in this study were Ar and $H_2$, and two kinds of nhmgen source gases, $N_2$ and <$NH_3$, were also employed. The as-grown films were characterized by XPS, IR, SEM and Knoop microlhardness tester. The relationship between the films hardness and the growth rate indicated that the hardness of the film was dependent on several factors such as nitrogen source gas, substrate temperature and film thickness due to the variation of the composition and the structure of the film. Both nitrogen and carbon content could raise the film hardness, on which nitrogen content did stronger effect than carbon. The smooth morphology and continuous structure was benefit of obtaining high hardness. The maximum hardness of BON film was about 10 GPa.

• 한국식품영양과학회지
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• 제14권1호
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• pp.1-12
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• 1985

가열 및 동결저장이 오징어, 굴, 새우 및 명태의 in vitro 소화율과 trypsin indigestible substrate (TIS) 함량 변화에 미치는 영향을 실험한 결과는 다음과 같다. Boiling 했을 때 최고의 운 in vitro 소화율을 나타내는 시간은 오징어 1분, 내장을 제거한 굴 0.5분, 내장을 제거하지 않은 굴은 1분이었고, 명태는 5분 이었으며, 오징어와 굴은 부위에 따라 소화율은 다르게 나타났다. 최고의 in vitro 소화율을 나타내는 steaming 조건은 오징어는 $100^{\circ}C$에서 1분, 굴은 $88^{\circ}C$에서 1분이었으며, 명태는 $100^{\circ}C$에서 $1{\sim}2.5$분이었다. TIS는 진시료에서 in vitro 소화율과 역상관관계를 가지며 변화하였다. 동결건조한 시료가 다른 건조품보다 현저하게 높은 in vitro 소화율을 보였으나, 내장을 제거했거나 지방함량이 낮은 시료를 천일건조했을 때도 동결건조시료에 버금가는 in vitro 소화율을 나타내었다. 동결저장은 지방함량이 낮은 시료의 in vitro 소화율의 저하 및 TIS함량 증가에 효과적이었으나, 지방함량이 높아 산패가 심하게 진행된 시료에는 현저한 효과를 볼 수 없었다. 지방함량은 수산식품단백질을 가열처리했거나 저장했을 때의 소화율 변화에 결정적인 영향을 미침을 알 수 있었으며, 4가지의 효소를 이용한 multi-enzyme digestion technique은 수산식품단백질의 소화율 변화를 측정함에 있어 아주 민감하고 유용한 방법으로 판명되었다.

• 대한전자공학회논문지SD
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• 제39권3호
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• pp.1-8
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• 2002

Sol-gel 법으로 제작한 (Pb/sub 0.9/La/sub 0.1/)Ti/sub 0.975/O₃(PLT (10)) 박막의 구조적 및 전기적 특성에 대한 과잉 Pb 첨가량이 미치는 영향을 조사하였다. DTA 와 X-선 회절분석 결과, 과잉 Pb 첨가량이 7.5 에서 15㏖%로 증가함에 따라, PLT(10) 박막의 결정화 온도는 감소하였으며, (100) 우선 배향성은 증가하였다. 또한, PLT(10) 박막의 과잉 Pb 첨가량에 따른 전기적 특성을 조사한 결과, 12.5㏖% 의 과잉 Pb 를 첨가한 박막이 가장 우수한 전기적 특성을 나타내었다. 이때, 비유전률과 유전손실은 각각 350 과 0.02 이었고, 100㎸/㎝ 에서 누설전류밀도는 1.27×10/sup -6/A/㎠ 이었다. 또한 이력곡선으로부터 구한 잔류분극(p) 과 항전계 (Ec) 는 각각 6.36μC/㎠ 와 58.7㎸/㎝ 이었으며, ±5V 의 사각펄스를 10/sup 9/회 인가한 후에도 잔류 분극값이 초기값의 약 15% 감소하는 비교적 우수한 피로특성을 나타내었다. 이상의 결과로부터, 과잉 Pb 첨가량이 12.5㏖% 인 PLT(10) 박막은 비휘발성 메모리에 응용될 수 있는 매우 유망한 재료임을 알 수 있었다.

• 한국재료학회지
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• 제21권4호
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• pp.216-219
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• 2011

Perovskite manganites such as $RE_{1-x}A_xMnO_3$ (RE = rare earth, A = Ca, Sr, Ba) have been the subject of intense research in the last few years, ever since the discovery that these systems demonstrate colossal magnetoresistance (CMR). The CMR is usually explained with the double-exchange (DE) mechanism, and CMR materials have potential applications for magnetic switching, recording devices, and more. However, the intrinsic CMR effect is usually found under the conditions of a magnetic field of several Teslas and a narrow temperature range near the Curie temperature ($T_c$). This magnetic field and temperature range make practical applications impossible. Recently, another type of MR, called the low-field magnetoresistance(LFMR), has also been a research focus. This MR is typically found in polycrystalline half-metallic ferromagnets, and is associated with the spin-dependent charge transport across grain boundaries. Composites with compositions $La_{0.7}(Ca_{1-x}Sr_x)_{0.3}MnO_3)]_{0.99}/(BaTiO_3)_{0.01}$ $[(LCSMO)_{0.99}/(BTO)_{0.01}]$were prepared with different Sr doping levels x by a standard ceramic technique, and their electrical transport and magnetoresistance (MR) properties were investigated. The structure and morphology of the composites were studied by X-ray diffraction (XRD) and scanning electronic microscopy (SEM). BTO peaks could not be found in the XRD pattern because the amount of BTO in the composites was too small. As the content of x decreased, the crystal structure changed from orthorhombic to rhombohedral. This change can be explained by the fact that the crystal structure of pure LCMO is orthorhombic and the crystal structure of pure LSMO is rhombohedral. The SEM results indicate that LCSMO and BTO coexist in the composites and BTO mostly segregates at the grain boundaries of LCSMO, which are in accordance with the results of the magnetic measurements. The resistivity of all the composites was measured in the range of 90-400K at 0T, 0.5T magnetic field. The result indicates that the MR of the composites increases systematically as the Ca concentration increases, although the transition temperature $T_c$ shifts to a lower range.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.1181-1184
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• 2008

$GeO_2$/ormosil organic-inorganic hybrid films doped with neodymium ions and $TiO_2$/Ormosil organic-inorganic hybrid films dispersed with neodymium oxide nanocrystals are prepared by combining an inverse microemulsion technique and a low-temperature sol-gel technique. The effects of $Nd^{3+}$ concentration, $Nd_2O_3$ nanocrystal content, and heat treatment temperature on up-conversion and photoluminescence luminescence properties of the hybrid films are studied.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
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• pp.632-635
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• 2003

[ $(Ba,Sr,Ca)TiO_3$ ] powders, prepared by the sol-gel method, were mixed with organic vehicle and the BSCT thick films were fabricated by the screen printing techniques on alumina substrates. The dielectric properties were investigated for various composition ratio and $Nb_2O_5$ doping contents. All the BSCT thick films, sintered at $1420^{\circ}C$, showed the typical XRD patterns of a perovskite polycrystalline structure. The Curie temperature and the relative dielectric constant decreased with increasing Ca content and $Nb_2O_5$ doping amount. The relative dielectric constant, dielectric loss and tunability of the BSCT(50/40/10) thick films doped with 1.0wt% $Nb_2O_5$ were 1410, 0.65% and 17.29% respectively.

• 한국표면공학회지
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• 제29권6호
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• pp.803-808
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• 1996

Material and electrical characteristies of copper thin films prepared by metal organic chemical vapor deposition (MOCVD) have been investigated for interconnection applications in ultra large scale integration circuits (ULSI). The copper films have been deposited a TiN substrates using a metal organic precursor, hexafluoro acetylacetonate trimethyvinylsilane copper, VTMS(hfac)Cu (I). Deposition rate, grain size, surface morphology, and electrical resistvity of the copper films have been measuredfrom samples prepared at various experimental conditions, which include substrate temperature, chamber pressure, and carrier gas flow rate. Results of the experiment showed that the electrical property of the copper films is closely related to the crystallinity of the films. Lowest electrical resistivity, $2.4{\mu}{\Omega}.cm$ was obtained at the substrate temperature of $180^{\circ}C$, but the resistivity slightly increased with increasing substrate temperature due to the carbon content along the copper grain boundaries.

• 한국표면공학회지
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• 제32권6호
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• pp.686-694
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• 1999

Insoluble anodes of the Ta/Ir mixed metal oxide for electrodeposition of Ni-W alloy in ammoniacal citrate bath were prepared by thermal decomposition method. Ti plate was etched in boiling oxalic acid solution and coated with ethanol solution of $TaCl_{5}$ and $IrCl_4$ mixed in a fixed ratio, followed by drying and treating at various temperatures. The coating layer of these insoluble anode was characterized by SEM, EDX, XRD and DSC. The decomposition rate of citric acid in plating bath was determined by measuring the $CO_2$ gas evolved at the anodes with Gas Chromatography. Evolution of $CO_2$ gas from Ta/Ir oxide anodes decreased about 5% compared with that of Pt. The $CO_2$ gas evolution was increased with the amount of Ir-oxide in the coatings. The coatings which have more than 40% ratio of Ta content and heat-treated at the temperature higher than $400^{\circ}C$ showed better efficiency

• 한국식품영양과학회지
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• 제28권1호
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• pp.145-152
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• 1999

To explore the possibility of using freeze dried loach for instant choo o tang(Korean traditional loach soup), protein qualities and fatty acid composition were evaluated on boiled and steamed loach. Total lipid and ash content were lowered in both heated(boiled and steamed) loaches due to deboning and eviscerating during cooked meat preparation. Profiles of total amino acids were not changed seriously by the type of cooking, but the amount of essential amino acids were comparable in all samples. Two times more free amino acids were quantified in cooked samples compared to raw meat. Available lysine was marginally decreased by cooking, and that caused some measurable change in typsin indigestible substrate(TI) in streamed whole loach. In vitro protein digestibility of the heated loaches was not altered drastically and the protein quality determined as computed protein efficiency ratio(C PER) was similar for the raw, boiled and steamed loach. The ratios of unsaturated to saturated fatty acids changed measurably in heated whole loach. The results shows that heating caused apparent oxidative deterioration of the polyunsaturated fatty acids.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.157-159
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• 2001

The molten carbonate fuel cell has conspicuous feature and high potential in being used as an energy converter of various fuel to electricity and heat. However, the MCFC which use strongly corrosive molten carbonate at 650$^{\circ}C$ have many problem. Systematic investigation on corrosion behavior of Fe/20Cr/Ti alloys has been done in (62+38)mol% (Li+K)CO$_3$ melt at 923K by using steady state polarization and electrochemical impedance spectroscopy method. And, The research and development for the solid oxide fuel cell have been promoted rapidly and extensively in recent years, because of their high efficiency and future potential. Therefore this paper describes the manufacturing method and characteristics of anode electrode for SOFC, by the way, Ni-YSZ materials are used as anode of SOFC widely. So in this experiments, we investigated the optimum content of Ni, by the impedance characteristics, overvoltage. As a result, the performance of Ni-YSZ anode(47vo1%) was bettor excellent than the others.