• 한국세라믹학회지
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• 제46권5호
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• pp.441-446
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• 2009

Dense crack-free yttria film with 10 $\mu m$ thickness was prepared on aluminum by aerosol deposition. X-ray diffraction pattern on the film showed that it contained the same crystalline phase as the raw powder. Transmission electron microscopy revealed a nanostructured yttria film with grains smaller than 100 nm. Tensile adhesion strength between the film and aluminum substrate was 57.8 $\pm$ 6.3MPa. According to the etching test with $CF_4-O_2$ plasma, the etching rate of the yttria film was 1/100 that of quartz, 1/10 that of sintered alumina and comparable to that of sintered yttria.

• Kyungpook Mathematical Journal
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• 제16권2호
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• pp.267-279
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• 1976

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.429-429
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• 2016

Organolead halide perovskite have attracted much attention over the past three years as the third generation photovoltaic due to simple fabrication process via solution process and their great photovoltaic properties. Many structures such as mesoporous scaffold, planar heterojunction or 1-D TiO2 or ZnO nanorod array structures have been studied to enhance performances. And the photovoltaic performances and carrier transport properties were studied depending on the cell structures and shape of perovskite film. For example, the perovskite cell based on TiO2/ZnO nanorod electron transport materials showed higher electron mobility than the mesoporous structured semiconductor layer due to 1-D direct pathway for electron transport. However, the reason for enhanced performance was not fully understood whether either the shape of perovskite or the structure of TiO2/ZnO nanorod scaffold play a dominant role. In this regard, for a clear understanding of the shape/structure of perovskite layer, we applied anodized aluminum oxide material which is good candidate as the inactive scaffold that does not influence the charge transport. We fabricated vertical one dimensional (1-D) nanostructured methylammonium lead mixed halide perovskite (CH3NH3PbI3-xClx) solar cell by infiltrating perovskite in the pore of anodized aluminum oxide (AAO). AAO template, one of the common nanostructured materials with one dimensional pore and controllable pore diameters, was successfully fabricated by anodizing and widening of the thermally evaporated Al film on the compact TiO2 layer. Using AAO as a scaffold for perovskite, we obtained 1-D shaped perovskite absorber, and over 15% photo conversion efficiency was obtained. I-V measurement, photoluminescence, impedance, and time-limited current collection were performed to determine vertically arrayed 1-D perovskite solar cells shaped in comparison with planar heterojunction and mesoporous alumina structured solar cells. Our findings lead to reveal the influence of the shape of perovskite layer on photoelectrical properties.

• 한국식품저장유통학회지
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• 제23권3호
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• pp.291-300
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• 2016

상온($20{\sim}25^{\circ}C$)에서 후숙(0일~30일)된 참다래의 품질 및 영양성분 함량분석을 수행하였고 최적 후숙 기간을 구명하기 위해 항산화활성, 단백질 분해능과 관능평가를 수행하였다. 기간별 후숙된 참다래의 품질은 경도와 산도가 20일 이후부터 급격히 감소되는 경향을 보였고 식이섬유, 특히 수용성 식이섬유는 20일 이후에 함량이 크게 증가 하였으며 유리당과 유기산 함량도 대체적으로 20일 이후에 뛰게 각 증가와 감소하는 경향을 보였다. 총페놀과 총플라보노이드 함량은 20일 이후에 함량이 유의하게 높았고 아질산염 소거능도 이와 유사하게 증가하는 경향을 보였다. 또한 DPPH radical 소거능을 통한 항산화 효과와 tyrosinase 억제능을 이용한 미백효과는 기간이 길어질수록 감소하였는데 이는 비타민 C 함량 패턴과 유사하였다. 참다래에 함유된 단백질 분해효소 actinidin을 SDS-PAGE 분석을 통해 확인하였고 함량과 이의 효능을 조사한 결과 후숙 기간이 경과됨에 따라 actinidin의 함량과 단백질 분해능도 점차 증가하였으며 15~20일 이후에 급격히 높아지는 것을 확인하였다. 후숙 기간별 참다래의 관능평가도 수행 하였는데, 20일 째가 선호도가 가장 높았으며 흥미롭게도 30일 째에는 오히려 선호도가 떨어지는 경향을 보였다. 현재까지 저온 저장된 참다래의 상온 보관시 최적 후숙 기간에 관한 연구는 미흡한 실정으로 본 연구 결과는 소비자에게 저장 보관된 참다래의 소비 및 섭취에 있어서 도움이 될 것으로 생각된다.

• 한국표면공학회지
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• 제42권6호
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• pp.267-271
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• 2009

Multicomponent transparent conducting oxide films were deposited on glass substrates at 150 by dual magnetron sputtering of AZO and ITO targets. In the case of mixing a limited amount of ITO (10W), resistivity of TCO films was significantly increased compared to the AZO film; from $3.5{\times}10^{-3}$ to $9.7{\times}10^{-3}{\Omega}{\cdot}cm$. Deterioration of the electrical conductivity is attributed to the decreases in carrier concentration and Hall mobility. Improvement of the conductivity could be obtained for the films prepared with ITO powers larger than 40 W. The lowest resistivity ($\rho$) of $7.3{\times}10^{-4}{\Omega}{\cdot}cm$ was achieved when ITO power was 100 W. Effects of $H_2$ incorporation on the electrical and optical properties of AZO-ITO films were investigated in this work. Addition of small amount of hydrogen resulted in the increase of carrier concentration and the improvement of electrical conductivity. It is apparent that the roughness of AZO-ITO films decreases dramatically after the transition of microstructure from polycrystalline to amorphous phase, which gives practical advantages such as an excellent uniformity of surface and a high etching rate. AZO-ITO films grown at sputtering ambient with hydrogen gas are expected to be applicable to optoelectronic devices such as organic light emitting diodes and flexible displays due to their sufficient electrical and structural properties.

• 한국축산식품학회지
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• 제41권2호
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• pp.185-195
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• 2021

The objective of this study was to determine the effects of high pressure to investigate the technical functional properties of the protein solution extracted from an edible insect, Protaetia brevitarsis seulensis. High pressure processing was performed at 0 (control), 100, 200, 300, 400, and 500 MPa at 35℃. The essential amino acid index of the control was lower (p<0.05) than that of the P. brevitarsis seulensis extract treated with 100 MPa. The SDS-PAGE patterns tended to become faint at approximately 75 kDa and thicker at approximately 37 KDa after high pressure treatment. The protein solubility and pH of the protein tended to increase as the hydrostatic pressure levels increased. The instrument color values (redness and yellowness) of the P. brevitarsis seulensis protein treated with high pressure were lower (p<0.05) than those of the control. The forming capacity of the protein solution with P. brevitarsis seulensis treated with high pressure was higher (p<0.05) than that of the control. In conclusion, we confirmed that the technical functional properties of edible insect proteins extracted under high pressure of 200 MPa are improved. Our results indicate that high pressure can improve the technical functional properties of proteins from edible insects.

• Journal of the Korean Wood Science and Technology
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• 제48권4호
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• pp.488-502
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• 2020

In this study, the moisture absorption and desorption properties presented by the Health-Friendly Housing Construction Standards of South Korea were compared using the wood of three tree species (Douglas-fir, Hinoki, Larch) and two types of wood-based materials(Plywood, WML Board^Ⓡ). The national standards for functional building materials present that the amounts of moisture absorption and desorption should be at least 65g/㎡ on average, respectively according to the test method under KS F 2611:2009. Therefore, in this study, the moisture absorption/desorption properties of materials with no treatment (Control), with punching, and with surface stain finishing and the moisture absorption/desorption property improvement effects of the treatments were compared and analyzed. According to the results of this study, it was evaluated that all five types of wood and wood-based materials tested did not satisfy the amount of moisture absorption/desorption of at least 65g/㎡, which is the performance standard for moisture absorption/desorption functional building materials, indicating that untreated wood and wood-based materials cannot be applied as functional finishing materials according to the Health-Friendly Housing Construction Standards. The surface stain finishing greatly reduced the moisture absorption and desorption rates of the materials, and the amounts of moisture absorbed and desorbed were also shown to decrease by at least two times on average. When the surfaces of the materials were punched with Ø4mm holes at intervals of 20 mm, the moisture absorption/desorption areas increased from 18% to 51%, and this increase was shown to be capable of increasing the amounts of moisture absorbed/desorbed by 29% on average at the minimum, and 81% on average at the maximum. The effects of punching were shown to be identical even in cases where the materials were stain finished. For the application of wood or wood-based materials as eco-friendly, health-friendly, and moisture absorption/desorption functional building materials hereafter, it is judged that new physical and chemical improvement studies should be conducted, and treatment methods should be developed.

• 한국표면공학회지
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• 제42권3호
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• pp.128-132
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• 2009

Transparent conducting thin films of indium tin oxide(ITO) co-sputtered with aluminum-doped zinc oxide(AZO) were deposited on glass substrate by dual magnetron sputtering. It was found that the electrical properties and structural characteristics of the films are significantly changed according to the sputtering power of the AZO target. The IAZTO film prepared with D.C power of ITO at 100 W and R.F power of AZO at 50 W shows an electrical resistivity of $4.6{\times}10^{-4}{\Omega}{\cdot}cm$ and a sheet resistance of $30{\Omega}/{\square}$ (for 150 nm thick). Besides of the improvement of the electrical properties, compared to the ITO films deposited at the same process conditions, the IAZTO films have very smooth surface, which is due to the amorphous nature of the films. However, the electrical conductivity of the IAZTO films was found to be deteriorated along with the crystallization in case of the high temperature deposition (above $310^{\circ}C$). In this work, high quality amorphous transparent conductive oxide layers could be obtained by mixing AZO with ITO, indicating possible use of IAZTO films as the transparent electrodes in OLED and flexible display devices.

• 한국식품영양학회지
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• 제35권5호
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• pp.283-294
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• 2022

The purpose of this study was to develop a functional beverage by using Caragana sinica extract and Tremella fuciformis Berk, which have high physiological effects such as anti-diabetic, antioxidant, anticancer, anti-lipidemic and anti-inflammatory. To this end, we used various mixing ratios of Caragana sinica extract, Tremella fuciformis Berk, and isomalto oligosaccharide, and measured the physicochemical properties of those beverages. The analyses showed the following: moisture content of those beverages using Caragana sinica extract and Tremella fuciformis Berk was 50.51~67.64%, pH was 5.19~5.38, and crude fat content was 0.28~0.52%, crude protein content was 1.26~1.80%, ash content was 0.47~0.80 and sugar content was 8.55~26.98°Brix. The lightness (L) of the beverages was 37.70~58.11, the redness (a) was 6.88~16.94, the yellowness (b) was 13.72~23.68, the total polyphenol content was 2.07~3.46 mg/g, and the total flavonoid content was 0.37~0.42 mg/g. Based on the results, it was confirmed that the nutritional components and total polyphenols of functional beverage using Caragana Sinica Extract, Tremella Fuciformis Berk and isomalto oligosaccharide were high at a mixing ratio of 1:1.3:25%. These results will increase the use of Caragana Sinica Extract and Tremella Fuciformis Berk, as functional materials in the future, and provide a framework for the manufacturing of diluted beverages comprising mineral water and carbonated water.

• Applied Biological Chemistry
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• 제33권1호
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• pp.52-61
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• 1990

단백질의 기능성을 높이고자 acetic anhydride(AA), succinic anhydride (SA) 및 maleic anhydride(MA)로 단백질을 acyl화 시켜 소수성과 기능성 변화를 측정하여 기능 특성과 소수성의 관계를 고찰한 결과, 단백질의 아미노산 잔기인 amino기와 sulfhydryl기의 acyl화에는 AA에 의한 수식율이 가장 높아 amino기의 89.5 % sulfhydryl기의 72.2 %가 수식되었으며 amino기가 sulfhydryl기 보다 쉽게 acyl화 되었다. Succinyl화 및 maleyl화에 의해 어류 단백질의 소수성은 감소 하였으나 acetyl화는 단백질의 소수성이 근육 단백질보다 높다. AA, SA 및 MA로 acyl화 되면 단백질의 용해도, 유화특성, 포말특성, 수분 흡수력 및 지방 흡수력이 크게 향상되었으며 근육 단백질이 농축 단백질보다 기능적 특성이 좋았다. 단백질의 소수성 감소와 용해도 증가는 높은 상관을 보였고 유화특성 및 포말특성은 단백질의 용해도와 깊은 관련이 있었으며 단백질의 소수성도 중요하였다. 단백질의 수분 흡수력은 용해도와 상관이 크나 소수성과는 큰 관계가 없었으며 지방 흡수력은 단백질의 용해도 보다는 소수성에 더 큰 영향을 받는다.