• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.1730-1733
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• 1997

In this paper, a realization of a subband coding with TMS320C80 is studied. TMS320C80 is a multi-media processor specially designed for an image process. A main topic of this paper, as mentioned above, is an application of TMS320C80 to subband coding. Subband coding is the coding that devides full image to several subbands and encodes each subband with different coding methods. As using that methods, good image compression can be obtained. First above all, goal of this paper deals with TMS320C80 in coding still image and useds it in expending it's application to 3-D video coding.

• Journal of Electrochemical Science and Technology
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• 제6권3호
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• pp.95-105
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• 2015

In the present work, Carbon supported Pt₁₀₀, Pt₈₀Sn₂₀, Pt₈₀Ni₂₀ and Pt₈₀Sn₁₀Ni₁₀ electrocatalysts with different atomic ratios were prepared by ethylene glycol-reduction method to study the electro-oxidation of ethanol in membraneless fuel cell. The electrocatalysts were characterized in terms of structure, morphology and composition by using XRD, TEM and EDX techniques. Transmission electron microscopy measurements revealed a decrease in the mean particle size of the catalysts for the ternary compositions. The electrocatalytic activities of Pt₁₀₀/C, Pt₈₀Sn₂₀/C, Pt₈₀Ni₂₀/C and Pt₈₀Sn₁₀Ni₁₀/C catalysts for ethanol oxidation in an acid medium were investigated by cyclic voltammetry (CV) and chronoamperometry (CA). The electrochemical results showed that addition of Ni to Pt/C and Pt-Sn/C catalysts significantly shifted the onset of ethanol and CO oxidations toward lower potentials. The single membraneless ethanol fuel cell performances of the Pt₈₀Sn₁₀Ni₁₀/C, Pt₈₀Sn₂₀/C and Pt₈₀Ni₂₀/C anode catalysts were evaluated at room temperature. Among the catalysts investigated, the power density obtained for Pt₈₀Sn₁₀Ni₁₀/C (37.77 mW/cm² ) catalyst was higher than that of Pt₈₀Sn₂₀/C (22.89 mW/cm² ) and Pt₈₀Ni₂₀/C (16.77 mW/ cm² ), using 1.0 M ethanol + 0.5 M H₂SO₄ as anode feed and 0.1 M sodium percarbonate + 0.5 M H₂SO₄ as cathode feed.

• Advances in nano research
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• 제12권1호
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• pp.25-35
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• 2022

Within the framework of the density functional theory combined with the method of non-equilibrium Green's functions (DFT + NEGF), the features of electron transport in fullerene nanojunctions, which are «core-shell» nanoobjects made of a combination of fullerenes of different diameters C₂₀, C₈₀, C₁₈₀, placed between gold electrodes (in a nanogap), are studied. Their transmission spectra, the density of state, current-voltage characteristics and differential conductivity are determined. It was shown that in the energy range of -0.45-0.45 eV in the transmission spectrum of the "Au-C₁₈₀-Au" nanojunction appears a HOMO-LUMO gap with a width of 0.9 eV; when small-sized fullerenes C₂₀, C₈₀ are intercalation into the cavity C₁₈₀ the gap disappears, and a series of resonant structures are observed on their spectra. It has been established that distinct Coulomb steps appear on the current-voltage characteristics of the "Au-C₁₈₀-Au" nanojunction, but on the current-voltage characteristics "Au-C₈₀@C₁₈₀-Au", "Au-(C₂₀@C₈₀)@C₁₈₀-Au" these step structures are blurred due to a decrease in Coulomb energy. An increase in the number of Coulomb features on the dI/dV spectra of core-shell fullerene nanojunctions was revealed in comparison with nanojunctions based on fullerene C₆₀, which makes it possible to create high-speed single-electron devices on their basis. Models of single-electron transistors (SET) based on fullerene nanojunctions "Au-C₁₈₀-Au", "Au-C₈₀@C₁₈₀-Au" and "Au-(C₂₀@C₈₀)@C₁₈₀-Au" are considered. Their charge stability diagrams are analyzed and it is shown that SET based on C₈₀@C₁₈₀-, (C₂₀@C₈₀)@C₁₈₀- nanojunctions is output from the Coulomb blockade mode with the lowest drain-to-source voltage.

• 약학회지
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• 제45권3호
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• pp.282-286
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• 2001

To investigate the different mechanism between ATP and compound 48/80 (C$_{48}$80/)-induced histamine release, we observed effects of calcium antagonists in histamine release of rat peritoneal mast cells. Verapamil and diltiazem (voltage-dependent calcium channel blocker) and TMB-8 (a blocker of intracellular calcium release) significantly inhibited ATP-induced histamine release, but did not inhibit $C_{48}$80/-induced histamine release. Econazole (a blocker of receptor-operated calcium channel) dose-dependently inhibited both ATP and $C_{48}$80/-induced histamine release, but inhibitory effect of econazole in ATP-induced histamine release was more potent than that in $C_{48}$80/-induced histamine. EGTA dose-dependently inhibited ATP and $C_{48}$80/-induced histamine release, but $C_{48}$80/-induced histamine release was slightly inhibited by high concentrations (>2 mM) of EGTA. These results suggest that ATP-induced histamine release is related to broth intracellular calcium release and extracellular calcium influx via voltage-dependent calcium channel and receptor-operated calcium channel. $C_{48}$80/-induced histamine release is related to extracellular calcium influx, especially by receptor-operated calcium channel rather than voltage-dependent calcium channel.

• 한국식품저장유통학회지
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• 제16권5호
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• pp.765-771
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• 2009

본 연구는 생식으로만 이용하고 있는 어수리 잎을 이용한 기능성 제품을 개발하는데 기초자료를 제공하기 위하여 물과 에탄올을 사용하여($80^{\circ}C$ 50% 에탄올/ $20^{\circ}C$ 50% 에탄올/ $80^{\circ}C$ water/ $20^{\circ}C$ water) 어수리를 추출하여 항산화 활성을 살펴보았다. 항산화성 물질 중 총 폴리페놀 함량은 $80^{\circ}C$에서 50% 에탄올 추출물이 64.73 mg GAE/g으로 가장 높은 함량을 나타내었다. 항산화활성을 측정한 결과 $80^{\circ}C$에서 50% 에탄올로 추출하였을 때 DPPH radical 소거능은 50 ppm에서 69.14%, reducing power는 1000 ppm에서 흡광도 0.93을 나타내었고, ABTS+ radical 소거능은 1000 ppm에서 85.62%의 성을 보여 본 연구에서 사용한 추출방법 중 가장 높은 항산화활성을 보였다. 항산화 활성이 높게 나타난 50% 에탄올 추출물의 일반성분 측정결과 수분함량은 6.38%, 조단백질 함량은 4.35%, 조지방 함량은 0.67%, 그리고 조회분 함량은 1.96%였다. 또한 무기질 분석결과 Na 53.41 mg/100 g, K 396.26 mg/100 g, Mg 5.80 mg/ 100 g, P 47.17 mg/100 g, Zn 0.40 mg/100 g, Fe 5.27 mg/100 g, 그리고 Ca 3.56 mg/100 g으로 나타났다. 기능성 소재 개발의 일환으로 어수리 에탄올 추출물의 항산화관련 성분을 분석한 결과 총 페놀함량과 플라보노이드 함량은 각각 64.73 mg GAE/g과 49.54 mg RE/g로 나타났다. 이상의 결과로 볼 때 어수리를 이용한 기능성식품 제조 시 $80^{\circ}C$에서 50% 에탄올을 이용하여 추출하는 것이 항산화 효과를 높일 수 있는 방법이라고 생각된다.

• Journal of Microbiology and Biotechnology
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• 제24권10호
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• pp.1382-1388
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• 2014

Proteus vulgaris K80 lipase was expressed in Escherichia coli BL21 (DE3) cells and immobilized on amine-terminated magnetic microparticles (Mag-MPs). The immobilization yield and activity retention were 84.15% and 7.87%, respectively. A homology model of lipase K80 was constructed using P. mirabilis lipase as the template. Many lysine residues were located on the protein surface, remote from active sites. The biochemical characteristics of immobilized lipase K80 were compared with the soluble free form of lipase K80. The optimum temperature of K80-Mag-MPs was $60^{\circ}C$, which was $20^{\circ}C$ higher than that of the soluble form. K80-Mag-MPs also tended to be more stable than the soluble form at elevated temperatures and a broad range of pH. K80-Mag-MP maintained its stable form at up to $40^{\circ}C$ and in a pH range of 5.0-10.0, whereas soluble K80 maintained its activity up to $35^{\circ}C$ and pH 6.0-10.0. K80-Mag-MPs had broader substrate specificity compared with that of soluble K80. K80-Mag-MPs showed about 80% residual relative activity after five recovery trials. These results indicate the potential benefit of K80-Mag-MPs as a biocatalyst in various industries.

• Bulletin of the Korean Chemical Society
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• 제35권4호
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• pp.1005-1010
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• 2014

We have performed DFT calculations to devise some possible fullerene dimers (from $C_{60}$ and $C_{80}$) connected through $C_{24}$ and $C_{36}$ bridge cages with the face-to-face linking model. The fullerene dimers with $C_{36}$ bridges have lower binding energies and greater HOMO-LUMO gaps than those of the fullerene dimers with $C_{24}$ bridges. Also, the replacement of $C_{60}$ cages with $C_{80}$ ones always leads to an increase in binding energies and HOMO-LUMO gaps in these systems. Dimerization of $C_{60}$ and $C_{80}$ fullerenes with $C_{24}$ and $C_{36}$ results in a significant decrease in antiaromaticity of the antiaromatic cages $C_{24}$ and $C_{80}$, and an increase in the aromaticity of the aromatic cages $C_{36}$ and $C_{60}$. Therefore, DFT results indicate that those fullerene dimers involving the initially harshly antiaromatic $C_{24}$ or $C_{80}$ cages are more energetically favorable configuration than the fullerene dimers involving the aromatic $C_{36}$ and $C_{60}$ cages.

• 한국광물학회지
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• 제26권2호
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• pp.81-86
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• 2013

버네사이트를 25, 40, 60과 $80^{\circ}C$ 각각에서 합성하였다. 이들 각 시료에 대해 X-선회절분석을 실시한 결과 합성 온도가 $25^{\circ}C$에서 $60^{\circ}C$까지 증가 시 X-선회절분석의 피크의 강도가 강해지는 반면 $80^{\circ}C$에서는 오히려 피크의 강도가 약해지는 것으로 나타났다. 이는 $60^{\circ}C$에서 합성된 버네사이트의 결정도가 상대적으로 가장 높다는 것을 의미한다. 그러나 60과 $80^{\circ}C$에서 합성된 버네사이트의 BET 비표면적은 39.4에서 89.7 $m^2/g$로 증가한다. SEM 분석 결과 $25^{\circ}C$에서 합성된 버네사이트의 경우 2~500 nm 크기의 구형으로 나타난 반면 합성 온도가 증가함에 따라 판상의 버네사이트가 관찰되었다. 뿐만 아니라, $80^{\circ}C$에서 합성된 버네사이트의 경우 $60^{\circ}C$에서 합성된 버네사이트와는 달리 판상의 결정에 많은 다공성을 띠고 있다. 따라서 $80^{\circ}C$에서 합성된 버네사이트의 BET 비표면적 증가는 합성된 버네사이트 결정 내 다공성증가에 의한 것으로 판단된다. 따라서 합성된 버네사이트의 결정성, 형성 등과 같은 다양한 이화학적 특성은 온도와 같은 영향인자에 의해 매우 민감하게 변화함을 보여주고 있다.

• 한국식품과학회지
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• 제30권5호
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• pp.1012-1017
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• 1998

진품콩에 함유된 lipoxygenase, urease, trypsin inhibitor, 탄닌, 피트산을 60, 80, $100^{\circ}C$로 열처리 하는 중의 함량변화를 조사하였다. lipoxygenase-1은 $60^{\circ}C$로 가열할 경우 100 분까지 활성이 있었으나, $80^{\circ}C$, $100^{\circ}C$에서는 20분과 10분 후에 활성이 없어졌다. lipoxygenase-2와 lipoxygenase-3의 활성은 없었다. urease활성은 $60^{\circ}C$로 100분을 가열하여도 초기와 비슷하였으나, $80^{\circ}C$에서는 20분, $100^{\circ}C$에서는 10분만에 완전히 불활성화 되었다. 트립신 저해제는 $60^{\circ}C$에서는 비교적 서서히 파괴되어 100분 후에는 58.6%가 활성이 없어졌으며, $80^{\circ}C$와 $100^{\circ}C$의 경우는 가열 초기에 급격히 파괴되지만, $20{\sim}30$분 후부터는 파괴 속도가 느려지면서 $80^{\circ}C$에서 100 분간 가열한 후에는 78.1%, $100^{\circ}C$에서 50분간 가열한 후에는 91.9%가 활성이 없어졌다. 열처리한 진품 콩에 있는 탄닌 함량은 열처리 중 다소 증가되었다. 피트산 양은 $60^{\circ}C$로 열처리 할 때 증가되었고, $80^{\circ}C$에서는 거의 변화가 없었고, $100^{\circ}C$로 50분 가열하였을 때는 감소하였다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2005년도 제24회 춘계학술대회논문집
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• pp.31-34
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• 2005

미세균열이 생기기 전 $80^{\circ}C$ 물속에서 침수시간이 변함에 따른 $Avimid^{R}$ K3B/IM7 복합재의 습기노화현상에 관하여 연구하였다. $80^{\circ}C$ 물속에서 복합재의 강성을 저하시키는 요인으로는 수지 강성의 저하나 잔류응력의 변화 그리고 섬유와 수지 사이의 계면 손상이다. $80^{\circ}C$ 물속에서 수지에 습기가 포화되는 시간은 500 시간이며 K3B/IM7 복합재에 습기가 포화되는 시간은 100 시간이다. $80^{\circ}C$ 물속에서 수지가 500 시간 가속노화한 후 DSC 시험을 한 결과 $T_{g}는 1\%$ 이내 증가하였으며 무게는 $1.55\%$증가하였다. $80^{\circ}C$ 물속에서 수지의 습기 포화 속도가 복합재의 습기 포화 속도 보다 빨랐다. 500 시간 노화한 후 수지의 파괴인성은 $37\%$ 저하하였으며 100 시간 노화한 후 [+45/0/-45/90]s K3B/IM7 복합재의 미세균열 파괴인성은 $28\%$ 감소하였다.