• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 1998년도 춘계학술대회 및 발표대회 강연 및 발표논문 초록집
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• pp.17-17
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• 1998

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.333-336
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• 2009

A series of microcavity plasma devices having various electrode geometries were investigated for the display and lighting applications. Addressable, self-assembled Al/$Al_2O_3$ electrodes were fabricated in a thin, flexible single sheet of Al foil. And, enhanced luminance and efficient microplasmas are achieved by precise control of the cross-sectional geometry and surface morphology of the cavities within the microplasma devices. New microdischarge system fabricated in various substrates will be introduced.

• 한국식품영양학회지
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• 제12권1호
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• pp.85-90
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• 1999

The characcteristics of anthocyanin pigments from crab apple (Malus prunifolia Wild. Borkh. "red fruit") by ethanol extract were investigated at various condition of light temperature sugar, organic acid me-tal ion and pH. The pigments were stable(over the 60%) on the light irradiation throughout 20 days sto-rage period at room temperature and in the pesenc of Al-foil red blue green and yellow cover were rage period at room temperature and in the pesence of Al-foil red blue green and yellow cover were very stable. The pigments also showed high thermal stbility(over the 67% at 115$^{\circ}C$ 10min) at pH2.5 respectively. The pigments with added organic acid greatly increased thickness of red color. The pig-ments with added metal ions at pH 2.5 such as Na+ K+, Mg2+ Ca2+ and Mn2+ were stable throughout 20 days storage period at $25^{\circ}C$. But Cu2+ addition showed the rapidly degradation of the pigments and Al3+ addition induced the color conversion from red to redish violet. The thickness of the red color of anthocyanin pigments increased increased as the pH decreased. These results indicated that crab apple antho-cyanin pigments might be potental source of natural food colorant. colorant.

• 한국세라믹학회지
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• 제51권6호
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• pp.549-553
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• 2014

$CoSb_3$-based skutterudite compounds are candidate materials for thermoelectric power generation in the mid-temperature range (600 - 900 K) because their thermoelectric properties can be enhanced by doping and filling. The joining property of thermoelectric module electrodes containing thermoelectric materials is of great importance because it can dominate the efficiency of the thermoelectric module. This study examined the properties of $CoSb_3$/Al/Ti/CuMo joined by the spark plasma sintering technique. Titanium thin foil was used to prevent the diffusion of copper into $CoSb_3$ and Aluminum thin foil was used to improve the adhesion between $CoSb_3$ and Ti. The insertion of an Aluminum interlayer between the Ti and $CoSb_3$ was effective for joining $CoSb_3$ to Ti by forming an intermediate layer at the Al-$CoSb_3$ boundary without any micro cracks. Specifically, the adhesion strength of the Ti/Al/$CoSb_3$ joining interface showed a remarkable improvement compared with our previous results, without deterioration of electrical property in the interface.

• 한국재료학회지
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• 제11권1호
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• pp.48-54
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• 2001

고순도알루미늄 유전체의 내부표면적을 증가시키기 위하여 1M의 염산 에칭용액에 첨가제를 사용했을 때 나타나는 에칭특성의 변화를 조사하였다. 염산용액에 에틸렌글리콜이 첨가된 혼합용액에서 에칭을 실시했을 경우 알루미늄 기지 표면에 미세하고 균일한 에치피트가 형성되어 표면적 증가 효과가 크게 나타났으며, 또한 양극 산화 후 측정된 정전용량의 결과에서도 에틸렌 글리콜이 첨가된 에칭액에서 제조된 유전체는 표면적 증가에 의한 높은 정전용량 값을 나타냈다.

• 한국세라믹학회지
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• 제26권5호
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• pp.593-600
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• 1989

Fine spinel powder was prepared from the Mg-Al double alkoxide synthesized using magnesium powder, aluminum foil and sec-butyl alcohol. This powder was compared with powder prepared by mixing two commercial alkoxides. The spinelization was started at 50$0^{\circ}C$ and was almost completed at 100$0^{\circ}C$ with a good crystallinity in the double alkoxide system. In mixed alkoxide system, homogeneous spinel powder was not obtained and MgO existed as a second phase because of solubility and hydrolysis rate differences of two alkoxides. The relative density of specimen prepared by double alkoxide was 99% and specimen prepared by mixed alkoxide was 95%. The modulus of rupture of specimens prepared by double alkoxide and mixed alkoxide was 49.9kg/$\textrm{mm}^2$ and 41.6kg/$\textrm{mm}^2$, respectively.

• 한국재료학회지
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• 제29권12호
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• pp.757-763
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• 2019

A stacked high-voltage (900 V) Al electrolytic capacitor made with ZrO₂ coated anode foils, which has not been studied so far, is realized and the effects of Zr-Al-O composite layer on the electric properties are discussed. Etched Al foils coated with ZrO₂ sol are anodized in 2-methyl-1,3-propanediol (MPD)-boric acid electrolyte. The anodized Al foils are assembled with stacked structure to prepare the capacitor. The capacitance and dissipation factor of the capacitor with ZrO₂ coated anode foils increase by 41 % and decrease by 50 %, respectively, in comparison with those of Al anode foils. Zr-Al-O composite dielectric layer is formed between separate crystalline ZrO₂ with high dielectric constant and amorphous Al₂O₃ with high ionic resistivity. This work suggests that the formation of a composite layer by coating valve metal oxide on etched Al foil surface and anodizing it in MPD-boric acid electrolyte is a promising approach for high voltage and volume efficiency of capacitors.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
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• pp.243.1-243.1
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• 2015

To replace the based on silicon solar cells, the third generation solar cells, Dye-sensitized solar cells (DSSCs), is low fabrication than silicon solar cells, environmentally friendly and can be applied to various field. For this reason, the DSSCs have been continuously researched. But DSSCs have one drawback that is the low power conversion efficiency (PCE) than silicon solar cells. To solve the problem, we used the backr-eflector the Al foil that can be easily obtained from the surrounding in order to improve the efficiency of the DSSCs. Easily detachable Al foil back-reflector increases the photocurrent by enhancing the harvesting light because the discarded light is reused. It also leads to enhance the power conversion efficiency (PCE). In addition, we compared with the efficiency of the DSSCs that is applied and does not be applied with back-reflector according to the thickness of the TiO2 photoelectrode. When the back-reflector is applied to DSSCs, the photocurrent is increased. It leads to affect the efficiency. We used to solar simulator and Electrochemical Impedance Spectroscopy (EIS) to confirm the PCE and resistance. The DSSCs were also measured by External Quantum effect (EQE). At the same time, FE-SEM and XRD were used to confirm the thickness of layer and crystal structural of photoelectrode.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.271-272
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• 2012

Bulk Metallic Glasses (BMGs or amorphous alloy) exhibit high strength and good corrosion resistance. Applications of thin films and micro parts of BMGs have been used a lot since its inception in the research of BMGs. However, Application and fabrication of BMGs are limited to make structural materials. Thin films of BMGs which is sputtered on the surface of structural materials by sputtering process is used to improve limits about application of BMGs. In order to investigate the difference of properties between designed alloys and thin films, we identified that thin films deposited on the surface that have the characteristic of the amorphous films and the composition of designed alloys. Zr-Cu (Cu=30, 35, 38, 40, 50 at.%) and Zr-Cu-Al (Al=10 at.% fixed, Cu=26, 30, 34, 38 at.%) alloys were fabricated with Zr (99.7% purity), Cu (99.997% purity), and Al (99.99% purity) as melting 5 times by arc melting method before rods 2mm in diameter was manufactured. In order to analyze GFA (Glass Forming Ability), rods were observed by Optical Microscopy and SEM and $T_g$, $T_x$, ($T_x$ is crystallization temperature and $T_g$ is the glass transition temperature) and Tm were measured by DTA and DSC. Powder was manufactured by Gas Atomizer and target was sintered using powder in large supercooled liquid region ($=T_x-T_g$) by SPS(Spark Plasma Sintering). Amorphous foil was prepared by RSP process with 5 gram alloy button. The composition of the foil and sputtered thin film was analyzed by EDS and EPMA. In the result of DSC curve, binary alloys ($Zr_{62}Cu_{38}$, $Zr_{60}Cu_{40}$, $Zr_{50}Cu_{50}$) and ternary alloys ($Zr_{64}Al_{10}Cu_{26}$, $Zr_{56}Al_{10}Cu_{34}$, $Zr_{52}Al_{10}Cu_{38}$) have $T_g$ except for $Zr_{70}Cu_{30}$ and $Zr_{60}Al_{10}Cu_{30}$. The compositions with $T_g$ made into powders. Figure shows XRD data of thin film showed similar hollow peak.

• 보존과학회지
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• 제38권2호
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• pp.124-132
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• 2022

본 연구는 국가민속문화재 일월수 다라니 주머니 매듭과 테두리 장식에 사용된 '금속 장식지'를 대상으로 과학적 분석을 통해 재료적 특성을 파악하였다. 금속 장식지는 SEM-EDS 분석을 통해 은(Ag) 및 황(S)이 확인되어 은제 금속박을 배지에 부착하여 제작한 것으로 추정할 수 있다. 황(S)은 농도와 접촉시간에 따라 은(Ag)을 황색부터 흑색까지 변색시킬 수 있다. 현재는 황색을 확인할 수 없으나, 은(Ag)으로 가금사를 만든 사례가 있어 본래 색을 추정하기 위해서는 추가 연구가 필요하다. 배지는 배면까지 적갈색이다. 함께 검출된 알루미늄(Al)과 규소(Si), 철(Fe)은 전통 편금사(片金絲)의 붉은색 접착제로 추정되는 주토(朱土)의 주성분으로, 금속 장식지의 접착제 관련 성분으로 추측된다. GC/MS 분석 결과에서 접착제 성분은 아교(阿膠)로 확인할 수 있었다.