• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.3-3
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• 2010

We investigated the influence of the indium content on the threshold voltage ($V_{th}$) shift of sol-gel-derived indium-gallium-zinc oxide (IGZO) thin film transistors (TFTs). Surplus indium composition ratio into IGZO decreases the value of $V_{th}$ of IGZO TFTs showed huge $V_{th}$ shift in the negative direction. $V_{th}$ shift decreases from 10 to -28.2V as Indium composition ratio is increased. Because the free electron density is increased according to variation of the Indium composition ratio.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.2
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• pp.87-95
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• 1996

We have studied the effects of La concentration on the optical and electrical properties of lead lanthanum titanate (PLT) thin films by using sol-gel method. Both the optical and electrical properties are greatly affected by the La concentration. The refreactiv eindices of the films varied from 2.23 to 1.93 with varying La concentration in the range from 15 to 33 mol%. The dielectric constants of the films vary form 340 to 870 with varying La concentration in the range form 15 to 33 mol%. Hysteresis loop becomes slimmer with the increase of La concentration form 15 to 28mol% and little fatter again with the increase of La concentration form 28 to 33 mol%. Among the films investigated in this research, PLT(28) thin film shows the best dielectric properties for the application to the dielectrics of ULSI DRAM's. At the frequency of 100Hz, the dielectric constant and the loss tangent of PLT(28) thin films are 940 and 0.08 respectively. Its leakage current density at 1.5${\times}10^{5}$V/cm is 1${\times}10^{-6}A/cm^{2}$. The comparision between the simulated and the experimental curves for the switching transient characteristics shows that PLT (28) thin films behaves like normal dielectrics.

• Geomechanics and Engineering
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• v.19 no.6
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• pp.543-554
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• 2019

İzmir Bay reserves high amount of residual alluvial deposits generated by Meles River at its stream mouth. These carried sediments with high water content and low bearing capacity are unsuitable in terms of engineering purposes. In-situ soil stabilization with deep soil mixing method is considered to improve properties of soil in this location. This method is widely used especially over Scandinavia, Japan and North America. Basically, the method covers mixing appropriate binder into the soil to improve soil profile according to the engineering needs. For this purpose, soil samples were initially provided from the site, classification tests were performed and optimum ratios of lime and cement binders were determined. Following, specimens representing the in-situ soil conditions were prepared and cured to be able to determine their engineering properties. Unconfined compression tests and vane shear tests were applied to evaluate the stabilization performance of binders on samples with different curing periods. Scanning electron microscope was used to observe time-dependent bonding progress of binders in order to validate the results. Utilization of 4% lime and 4% cement mixture for the long-term performance and 8% lime and 8% cement mixture for short term performance were suggested for the stabilization of Meles Delta soils. Development of CSH and CAH in a gel form as well as CSH crystals were clearly observed on SEM images of treated specimens.

• Korean Journal of Plant Resources
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• v.24 no.3
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• pp.304-308
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• 2011

The survival rate and thermal, crystal, and physicochemical properties of starches in chinese yam tubers irradiated to proton beam were determined. Survival rate was decreased with increased proton beam irradiation. Amylose content of D. opposita starches from different proton beam ranged from 13.2% to 17.8%. D. opposita starch at 5 Gy showed the highest ${\Delta}H_{gel}$ values (12.0 J/g) while D. opposita starch at 25 Gy showed the lowest values (10.1 J/g). Several parameters such as PKV (peak viscosity), HPV (Hot peak viscosity) and CPV (Cooling peak viscosity) decreased with the increase in irradiation dose. The degrees of crystallinity of the D. opposita starches at 5, 10, 15, 20 and 25 Gy were 37.2, 38.3, 38.9, 39.2 and 39.9%, respectively. It might be deduced that proton beam irradiation causes changes of starch, especially at high dose irradiation.

• Archives of Pharmacal Research
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• v.29 no.12
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• pp.1187-1192
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• 2006

The aims of this study were to encapsulate arbutin (AR) in liposome to enhance the skin-whitening activity, and to investigate the effect of liposome formulation on the entrapment efficiency (EE%), skin permeation rate and skin deposition. The liposomes were prepared by a film dispersion method with several different formulations and were separated from the solution by using the gel-filtration method. The physical (size distribution, morphology) and chemical (drug entrapment efficiency, hairless mouse skin permeation and deposition) properties of liposomes were characterized. The entrapment efficiency in all liposome formulations varied between 4.35% and 17.63%, and was dependent on the lipid content. The particle sizes of liposomes were in the range of $179.9{\sim}212.8\;nm$ in all liposome formulations. Although the permeation rate of AR in the liposome formulations decreased compared with AR solution, the deposition amount of AR in the epidermis/dermis layers increased in AR liposomal formulation. These results suggest that liposomal formulation could enhance the skin deposition of hydrophilic skin-whitening agents, thereby enhancing their activities.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.9 no.4
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• pp.371-376
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• 1999

A large NaX type zeolite crystal of a uniform particle size of 20$\mu\textrm{m}$ are grown with various {{{{{H}_{2}O}}}} content by hydrothermal reaction and added seed crystal (2~3$\mu\textrm{m}$) to reactant solution as a function of different adding seed levels from 3 to 15%. The result that increased purity of NaX zeolite above 95% and homogeneity of crystal size by increasing adding seed levels, also decreased crystallization time. It was explained that adding seed to synthesis solution leaded out increase of surface area for physical contact reaction and directed growth of seed crystal, so more rapid consumption of reaction gel as increase seeding levels.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.1
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• pp.73-77
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• 2005

Plant-derived natural products have been and will continue to be valuable sources. Elicitors have been employed to modify cell metabolism in order to enhance the productivity of useful metabolites in plant cell/tissue cultures. In this study, several elicitors were used to improve the productivity of useful metabolites and to reduce culture time for archiving high concentration in P. ginseng hairy root cultures. The addition of chitosan, chitosan oligosaccharide and alginate oligosaccharide to the culture of P. ginseng hairy roots caused growth to be inhibited with the increase in elicitor concentration. The usage of the chitosan elicitor and D-glucosamine caused a slight decrease in hairy root growth, whereas total ginseng saponin accumulated slightly with the increase in elicitor concentration. When gel beads were added to the culture medium at the initial period, hairy root growth was enhanced. The maximum growth was 1.35 times higher than that of the control at $1\%$ (w/v). Total ginseng saponin content decreased due to the addition of alginate beads. This would result in consistent diffusion of lower levels of calcium ions during the culture period that promotes biomass growth.

• Transactions on Electrical and Electronic Materials
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• v.12 no.3
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• pp.119-122
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• 2011

A series of mesoporous silicalites was synthesized using different compositions of tetraethylorthosilicate and methyltriethoxysilane (MTES) as the silica source. Cetyltrimethylammonium bromide was used as the organic template. Their detailed pore structures were investigated by transmission electron microscopy, X-ray diffraction, and N2 adsorption method. The thermal properties of these silicalites were studied by thermogravimetric analysis. The increased amount of MTES destroyed mesoporous channels and reduced pore sizes from 3.4 nm to 2.8 nm in calcined silicalites. The calcined silicalite transformed completely into an amorphous state at 30% MTES loading. Methyl pending groups of MTES hindered the structural ordering of ≡Si-O- frameworks, resulting in an amorphous structure. This was caused by the insufficient formation of supramolecular assembly with the organic template. No capillary condensation step was found in MS 7/3 silicalite. The other capillary condensation steps shifted toward the lower relative pressure with increasing MTES content, indicating the reduction of pore sizes.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.4
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• pp.584-590
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• 2009

The effects of different washing time and pH adjustment of surimi-like materials from pork leg on quality characteristics were investigated. Surimi was made from pork leg by washing two or four times with water, as well as by pH adjustments of 3.0 or 11.0. The control surimi was made by two times washing from Alaska pollock. The content of crude protein was higher in the surimi manufactured from pork leg with pH adjustments. The highest gel strength was found in the control, and the control had greater lightness and whiteness value. The control had higher texture attributes than the other samples, whereas the surimi from pork leg made by a pH 11.0 adjustment had higher texture attributes than the pH 3.0 adjustment. The sensory color was higher in the control compared to other surimi samples, whereas aroma was lower in the control. However, there were no significant differences in overall acceptability among the surimi samples.

• Fisheries and Aquatic Sciences
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• v.16 no.2
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• pp.71-78
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• 2013

Subcritical water hydrolysis was carried out in a batch reactor to produce valuable materials, such as low-molecular weight (MW) peptides and essential amino acids with antioxidant properties, from heat-dried squid viscera. Hydrolysis of squid viscera was performed at 160 to $280^{\circ}C$ for 3 min. The yield was increased by increasing the temperature and pressure, while the protein content of squid viscera hydrolysate decreased with increasing temperature. Low-MW peptides were detected in all hydrolysates by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The highest yields of free and structural amino acids in heat-dried squid viscera hydrolysate were at $160^{\circ}C$ and were $411.95{\pm}1.15$ and $346.62{\pm}1.25$ mg/100 g, respectively. All essential amino acids were detected in viscera hydrolysates; leucine was the most abundant. Antioxidant activities of hydrolysates were highest at $220^{\circ}C$. Greater than $98{\pm}0.26%$ of the ABTS antioxidant activity was retained in hydrolysates after long-term heat treatment.