• 한국수산과학회지
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• 제33권2호
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• pp.87-92
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• 2000

간장중의 활성산소 및 제거효소의 활성에 미치는 영향을 평가하기 위하여 미역의 건조분말을 $10{\%},\;20{\%},\;40{\%}$-첨가 조제한 미역국수 ($10{\%},\;20{\%},\;40{\%}\;FBA-noodle$)를 4주동안 SD계 흰쥐에 투여하여 미역국수의 생리작용을 평가하였다. $10{\%},\;20{\%},\;40{\%}$ FBA-noodle의 투여그룹의 mitochondria의 ${\cdot}OH$ 생성은 대조그룹 대비 각각 $20{\%},\;25{\%},\;35{\%}$의 현저한 OH 생성 억제효과가 인정되었다. 또한 $10{\%},\;20{\%},\;40{\%}$ FBA-noodle의 투여그룹의 microsome의 ${\cdot}OH$ 생성도 대조그룹 대비 $12{\~}20{\%}$의 유의적인 ${\cdot}OH$ 생성 억제효과가 인정되었다. $10{\%},\;20{\%},\;40{\%}$ FBA-noodle의 microsome의 $H_2O_2$의 생성은 유의적인 억제효과를 인정할 수 없었지만, cytosol중의 $O_2^({\cdot}-)$ 생성은 $20{\%},\;40{\%}$ FBA-noodle에서 $10{\%}$의 $O_2^({\cdot}-)$의 생성 억제효과가 인정되었다. $10{\%},\;20{\%},\;40{\%}$ FBA-noodle 투여그룹의 간장 mitochondria의 Mn-SOD 활성은 대조그룹 대비 $10{\~}15{\%}$의 Mn-SOD 활성의 증가효과가 인정되었다. 간장 microsome의 Mn-SOD 활성은 $10{\%} 및 20{\%}$ FBA-noodle 투여그룹은 Mn-SOD 활성의 유의적인 증가 효과를 인정할 수 없었지만, $40{\%}$ FBA-noodle 투여그룹은 $12{\%}$의 유의적인 Mn-SOD 활성 증가효과가 인정되었다. 또한 $10{\%},\;20{\%},\;40{\%}$ FBA-noodle의 투여그룹의 간장 cytosol의 Cu, Zn-SOD 활성은 대조그룹 대비 $10{\~}20{\%}$의 Cu, Zn-SOD 활성의 유의적인 증가효과가 인정되었다. 한편 간장 cytosol의 글루타치온 퍼옥시다아제 (GSHPx) 활성을 평가하여 보면 $10{\%}, 20{\%}, 40{\%}$ FBA-noodle 투여그룹의 cytosol의 GSHPx 활성은 대조그룹 대비 $20{\~}40{\%}$의 매우 효과적인 GSHPx활성의 증가효과가 인정되었다. $10{\%}, 20{\%}, 40{\%}$ FBA-noodle 투여그룹의 mitochondria의 LPO의 함량을 비교하여 보면 $10{\%}$ FBA-noodle은 유의적인 LPO의 생성 억제효과를 인정할 수 없었지만, $20{\%},\;40{\%}$ FBA-noodle은 $10{\%}$의 유의적인 LPO 생성 억제효과가 인정되었다. $10{\%},\;20{\%},\;40{\%}$ FBA-noodle 투여그룹의 microsome의 LPO의 함량은 $10{\%}$ FBA-noodle은 유의적인 LPO의 생성 억제효과를 인정할 수 없었지만, $20{\%} 및 40{\%}$ FBA-noodle은 약 $10{\~}12{\%}$의 유의적인 LPO 생성 억제효과가 인정되었다.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2011년도 춘계학술발표대회
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• pp.45.2-45.2
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• 2011

Metal organic frameworks (MOF) have generated considerable interests as a potential candidate for hydrogen storage owing to their extremely high surface-to-volume ratio and low density. In this study, Pt nanoparticles of about 3 nm in size were introduced outside MOF-5 [$Zn_4O$(1,4-benzenedicarbocylate)3], which was then encapsulated with hydrophobic microporous carbon black (denoted CB@Pt/MOF-5) in order to enhance hydrogen uptake capacity without decreasing the specific surface area and hydrostability. To study the chemical composition, morphology, crystal information, and properties of the synthesized material, a variety of techniques is employed, including WXRD, XPS, ICP-AES, FE-SEM, HR-TEM, and N2 adsorption-desorption, confirming the formation of novel hybrid composite designated CB@Pt/MOF-5 with highly crystalline structure, large specific surface area and pore volume. In addition, $H_2$ storage capacity for resulting material was measured using magnetic suspension microbalance at 77 and 298 K under high-pressure condition, and the hydrostability was also tested by exposing the sample to 33% relative humidity at $23^{\circ}C$ and measuring XRD as a function of time.

• 한국전기전자재료학회논문지
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• 제33권2호
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• pp.93-98
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• 2020

We investigated the effect of a post-annealing process using ultraviolet (UV) light on the electrical properties of solution-processed InZnO (IZO) thin-film transistors (TFTs). UV light was irradiated on IZO TFTs for different time periods of 0s, 30s, and 90s. We measured transfer and retention stability curves to evaluate the performance of the fabricated TFTs. In addition, we measured height, amplitude, and phase AFM images to analyze changes in the surface and morphology of the devices. AFM measurements were performed by setting the drive amplitude of the cantilever tip to 47.9 mV in tapping mode, then dividing the device surface into 500 nm × 500 nm. In the case of IZO TFT irradiated with UV for 30s, the electron mobility and I_on/I_off ratio were improved, the threshold voltage was reduced by approximately 2 V, and the subthreshold swing also decreased form 1.34 V/dec to 1.11 V/dec.

• 한국환경과학회지
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• 제26권1호
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• pp.119-131
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• 2017

This study evaluated the feasibility of recovering and recycling nitrogen (N) and phosphorus (P) from livestock excreta as struvite ($MgNH_4PO_4{\cdot}6H_2O$) in South Korea. Our experimental results showed that struvite precipitation was a very effective way to recover N and P from livestock excreta. Moreover, our study demonstrated that struvite precipitates from livestock excreta (SPL) contain higher concentrations of N, P, and magnesium (Mg) as compared to compost and liquid manure from livestock excreta. In addition, although SPL contain high concentrations of copper (Cu) and zinc (Zn), they meet the fertilizer criteria for concentrations of heavy metals. In South Korea, SPL cannot currently be used as a fertilizer due to legal constraints. Legal permission for SPL use would offer greater choice in livestock excreta management. In conclusion, recovery and recycling of N and P from livestock excreta as struvite can be an effective tool for managing nutrients in livestock excreta.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.145-148
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• 2007

The authors report on the fabrication of thin film transistors (TFTs) that use amorphous indium-gallium-zinc oxide (a-IGZO) channel and have the channel length (L) and width (W) patterned by dry etching. To prevent the plasma damage of active channel, a 100-nm-thckness $SiO_{x}$ by PECVD was adopted as an etch-stopper structure. IGZO TFT (W/L=10/50${\mu}m$) fabricated on glass exhibited the high performance mobility of $35.8\;cm^2/Vs$, a subthreshold gate voltage swing of $0.59V/dec$, and $I_{on/off}$ of $4.9{\times}10^6$. In addition, 4.1” transparent QCIF active-matrix organic light-emitting diode display were successfully fabricated, which was driven by a-IGZO TFTs.

• 한국전기전자재료학회논문지
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• 제19권5호
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• pp.442-449
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• 2006

Electrical, optical, and structural properties of indium zinc oxide (IZO) films grown by a box cathode sputtering (BCS) were investigated as a function of oxygen flow ratio. A sheet resistance of $42.6{\Omega}/{\Box}$, average transmittance above 88% in visible range, and root mean spare roughness of $2.7{\AA}$ were obtained even in the IZO layers grown at room temperature. In addition, it is shown that electrical characteristics of the top-emitting organic light emitting diodes (TOLEDs) with the BCS grown-IZO top cathode layer is better than that of TOLEDs with DC sputter grown IZO top cathode, due to absence of plasma damage effect. Furthermore the effects of oxygen flow ratio in IZO films are investigated, based on x-ray photoelectron spectroscopy (XPS), ultra violet/visible (UV/VIS) spectro-meter, scanning electron microscopy (SEM), and atomic force microscopy (AFM) analysis results.

• Corrosion Science and Technology
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• 제9권6호
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• pp.247-253
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• 2010

The characteristics of selective oxidation prior to hot-dip galvanizing with the annealing atmosphere dew point and chemical composition in dual-phase steels and their effect on the inhibition layer formation relevant to coating adhesion have been studied using a combination of electron microscopic and surface analytical techniques. The annealed and also galvanized samples of 3 kinds of Si/Mn ratios with varied amounts of Si addition were prepared by galvanizing simulator. The dew point was controlled at soaking temperature $800^{\circ}C$ in 15%$H_2$ -85%$N_2$ atmosphere. It was shown that good adhesion factors were mainly uniformity of oxide particle distribution of low number density and low Si/Mn ratio prior to hot-dip galvanizing. Their effect was the greatly reduced coating bare spots and the formation of uniform inhibition layer leading to good adhesion of Zn overlay. The mechanism of good adhesion is suggested by two processes: the formation of inhibition layer on the oxide free surface uncovered with no $SiO_2$-containing particles in particular, and the inhibition layer bridging of oxide particles. The growth of inhibition layer was enhanced markedly by the delayed reaction of Fe and Al with the increase of Si/Mn ratio.

• 한국분말재료학회지
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• 제27권4호
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• pp.305-310
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• 2020

In this study, partially dry transfer is investigated to solve the problem of fully dry transfer. Partially dry transfer is a method in which multiple layers of graphene are dry-transferred over a wet-transferred graphene layer. At a wavelength of 550 nm, the transmittance of the partially dry-transferred graphene is seen to be about 3% higher for each layer than that of the fully dry-transferred graphene. Furthermore, the sheet resistance of the partially dry-transferred graphene is relatively lower than that of the fully dry-transferred graphene, with the minimum sheet resistance being 179 Ω/sq. In addition, the fully dry-transferred graphene is easily damaged during the solution process, so that the performance of the organic photovoltaics (OPV) does not occur. In contrast, the best efficiency achievable for OPV using the partially dry-transferred graphene is 2.37% for 4 layers.

• 한국표면공학회지
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• 제52권4호
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• pp.233-238
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• 2019

The formation behavior of zinc phosphate conversion coating (ZPCC) on SCM430 alloy was investigated in 25 vol.% of 1M ZnO + 170 ml/L solution containing various $Fe(NO_3)_2$ concentrations, using open-circuit potential(OCP), electrochemical impedance spectroscopy(EIS), cyclic polarization(CP) curve and tape peel test. OCP of SCM430 alloy and corrosion current density increased with increasing $Fe(NO_3)_3$ concentration. Resistance of films formed on SCM430 alloy by chemical conversion treatment decreased with increasing $Fe(NO_3)_3$ concentration. Color and adhesion of chemical conversion coatings became darker and worse, respectively, with increasing $Fe(NO_3)_3$ concentration. It is concluded that addition of $Fe(NO_3)_3$ into a zinc phosphating bath leads to faster reaction to form porous surface coatings with poor adhesion and corrosion resistance.

• Elastomers and Composites
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• 제55권4호
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• pp.321-328
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• 2020

Zinc nitrate hexahydrate (Zn(NO3)2·6H2O) and sodium hydroxide (NaOH) were dissolved in distilled water and stirred for 30 min. The resulting solution was sonicated by an ultrasonic wave for 45 min. This solution was washed with distilled water and ethanol after centrifugation; next, it was placed in an electric furnace at 200℃ for 1 h under the flow of Ar gas to obtain zinc oxide nanoparticle. A zinc oxide nanoparticle-(C60) fullerene nanowhisker composite was synthesized using the zinc oxide nanoparticle solution, C60-saturated toluene, and isopropyl alcohol via the liquid-liquid interfacial precipitation method. The zinc oxide nanoparticle and zinc oxide nanoparticle-(C60) fullerene nanowhisker composite were characterized using X-ray diffraction, scanning electron microscopy, and Raman spectroscopy, and they were used for the catalytic degradation of methyl orange (MO) under ultraviolet (at 254 and 365 nm) and ultrasonic irradiation. In addition, the catalytic degradation of MO over the zinc oxide nanoparticle and zinc oxide nanoparticle-(C60) fullerene nanowhisker composite was evaluated using ultraviolet-visible spectroscopy.