• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.18 no.8
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• pp.678-685
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• 2006

Analysis of drying characteristics has been carried out with one-dimensional model in the dryer using the principle of the refraction of radiation. The dryer is composed of hot water tank, plastic film conveyer belt, drying material, etc. The model considers the con-duction and radiation within the plastic film and drying material. The film is semitransparent to radiation and the drying material is assumed to be semitransparent or opaque to radiation. The results show that the effect of radiative transfer on the drying rate is relatively large when the thickness of drying material is small and the water temperature is high. When the material is thin, the drying rate due to conduction is also enhanced and the drying time can considerably be reduced.

• Textile Coloration and Finishing
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• v.27 no.2
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• pp.126-131
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• 2015

Silica-polyurethane hybrid breathable films were prepared and their breathabilities were assessed. Appropriately aggregated silica was prepared through sol-gel reaction of water glass and its particle size ranged 360~500nm. The polyurethane dispersion was prepared by the reaction of isophorone diisocyanate(IPDI) as diisocyanate and polytetramethylene glycol(PTMG) and dimethylol propionic acid(DMPA) as polyol, particle size ranging 30~120nm. The reaction between isocyanate and hydroxyl group to form urethane bonding was checked by the intensity of the stretch peak of isocyanate at $2270cm^{-1}$ in the FT-IR. The silica was incorporated into polyurethane dispersion and casted into film. It was shown that the incorporated silica(1~5wt.%) increased water vapour permeability of the films by 30~100%, and decreased the hydrostatic pressure by 10~40%. From the results, it could be concluded that the appropriate hybridization of silica can increase the breathability of polyurethane dispersion film, while minimizing the loss of hydrostatic pressure.

• Food Science and Biotechnology
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• v.18 no.4
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• pp.889-894
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• 2009

Barley proteins are expected to have unique functional properties due to their high content of alcohol soluble protein, hordein. Since the barley proteins obtained by conventional isoelectric precipitation method cannot represent hordein fraction, barley proteins were fractionated to albumin, globulin, glutelin, and hordein with respect to extraction solvents. Functional properties and film-forming properties of solubility-fractionated barley proteins were investigated to explore their potential for human food ingredient and industrial usage. The 100 g of total barley protein comprised 5 g albumin, 23 g globulin, 45 g glutelin, and 27 g hordein. Water-binding capacities of barley protein isolates ranged from 140-183 mL water/100 g solid. Hordein showed the highest oil absorption capacity (136 mL oil/100 g), and glutelin showed the highest gelation property among the fractionated proteins. In general, the barley protein fractions formed brittle and weak films as indicated by low tensile strength (TS) and percent elongation at break (E) values. The salt-soluble globulin fraction produced film with the lowest TS value. Although films made from glutelin and hordein were dark-colored and had lower E values, they could be used as excellent barriers against water transmission.

• Applied Chemistry for Engineering
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• v.29 no.4
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• pp.484-487
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• 2018

In this paper, the optical and electrical properties of ytterbium films were studied for water vapor transmission rate (WVTR) analysis of encapsulation films used in organic electronic devices. Ytterbium thin films show a wide range of light transmittance (70-10%) and resistivity ($6.0-0.16m{\Omega}{\cdot}cm$) depending on various film thicknesses (20-100 nm). The Yb thin films were oxidized with moisture and its transmittance and resistance changed in real time. As a result, the WVTR of parylene and aluminum nitride (AlN) laminated thin encapsulation film was measured to be $4.3{\times}10^{-3}g/m^2{\cdot}day$ with the 25 nm thick ytterbium thin film.

• Journal of Photoscience
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• v.5 no.1
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• pp.11-15
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• 1998

The texture change of non-linear optical molecules at the air/water interface was investigated as a function of surface pressure with Brewster angle microscopy. The texture change resulted from the aggregation of dye molecules is important to understand the film uniformity and grain formation process. The 4-Octadecylhydroxy-4'-nitrostilbene (OHNS) generated the small spots of size around 1$\mu$m. The spots exhibit high contrast with other film area and do not show angle dependent reflectivity change. It is interesting to observe that the size of the domain stays the same as the film pressure increases. At high surface pressure, the contrast ratio of domains becomes high, which means dense packing of OHNS. And, the size of domain grows. In the middle of domain, highly contrasted domains are formed. The first and the second order transitions of OHNS observed from surface pressure-area isotherm result from the two types of grains. The N,N-Dihexadecylcyanoaniline (DHCA) formed highly contrasted gains over entire region, and the grains are the double layers. The difference in Langmuir film of OHNS and DHCA at the air/water interface is consistent with the small tilt angle from the surface normal for OHNS and the large tilt angle for DHCA in the Langmuir-Blodgett films.

• Corrosion Science and Technology
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• v.18 no.2
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• pp.39-48
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• 2019

The feasibility of using benzotriazole (BTAH) to inhibit pitting corrosion in the sprinkler copper tubes was investigated by filling the tubes with BTAH-water solution in 829 households at an eight-year-old apartment complex. The water leakage rate was reduced by approximately 90% following BTAH treatment during 161 days from the previous year. The leakage of one of the two sprinkler copper tubes was investigated with optical microscopy, scanning electron microscopy, energy dispersive spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction analysis to determine the formation of Cu-BTA film inside the corrosion pits. All the inner components of the corrosion pits were coated with Cu-BTA films suggesting that BTAH molecules penetrated the corrosion products. The Cu-BTA film was about 2 nm in thickness at the bottom of a corrosion pit. A layer of CuCl and $Cu_2O$ phases lies under the Cu-BTA film. This complex structure effectively prevented the propagation of corrosion pits in the sprinkler copper tubes and reduced the water leakage.

• Food Science and Biotechnology
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• v.17 no.6
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• pp.1203-1206
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• 2008

Silk fibroin (SF) film containing catechin was prepared and the antimicrobial activity as well as physical property of the film was examined. Tensile strength of the SF film decreased with increasing concentration of catechin, and water vapor permeability of the film decreased. The film's antimicrobial activity against Escherichia coli O157:H7 increased with increasing catechin concentration. Sausage samples were inoculated with E. coli 0157:H7 and Listeria monocytogenes, and the sausage packaged with the SF film containing catechin had a decrease in the populations of E. coli O157:H7 and L. monocytogenes by 0.83 and 0.85 log CFU/g after 12 days of storage, respectively, compared to the control. In addition, the sausage had a better quality than the control regarding lipid oxidation. Our results indicate that sausages can be packed with the SF film containing catechin to extend shelf life.

• Journal of the Semiconductor & Display Technology
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• v.21 no.2
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• pp.11-14
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• 2022

In this work, we evaluated the Al₂O₃ film, which was deposited by atomic layer deposition, degraded by exposure to harsh environments. The Al₂O₃ films deposited by atomic layer deposition have long been used as a gas diffusion barrier that satisfies barrier requirements for device reliability. To investigate the barrier and mechanical performance of the Al₂O₃ film with increasing temperature and relative humidity, the properties of the degraded Al₂O₃ film exposed to the harsh environment were evaluated using electrical calcium test and tensile test. As a result, the water vapor transmission rate of Al₂O₃ films stored in harsh environments has fallen to a level that is difficult to utilize as a barrier film. Through water vapor transmission rate measurements, it can be seen that the water vapor transmission rate changes can be significant, and the environment-induced degradation is fatal to the Al₂O₃ thin films. In addition, the surface roughness and porosity of the degraded Al₂O₃ are significantly increased as the environment becomes severer. the degradation of elongation is caused by the stress concentration at valleys of rough surface and pores generated by the harsh environment. Becaused the harsh envronment-induced degradation convert amorphous Al₂O₃ to crystalline structure, these encapsulation properties of the Al₂O₃ film was easily degraded.

• Food Science and Preservation
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• v.14 no.5
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• pp.451-456
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• 2007

The vitamin C content in extruded comstarch matrix was shown to depend on extrusion process variables (barrel temperature and water content), the packaging method, and the storage period. In addition, loss rates of vitamin C under different processing conditions were calculated. Extrusion process variable were barrel temperature ($80^{\circ}C,\;90^{\circ}C,\;100^{\circ}C$ and $110^{\circ}C$), and water content (25% 30% both w/w). The vitamin C content decreased as barrel temperature increased from $80^{\circ}C$ to $110^{\circ}C$ and water content increased from 25% to 30% when either LDPE plastic film packaging or ON film vacuum packaging were employed. As barrel temperature and water content increased, vitamin C decreased in comstarch packed in either LDPE film or ON film. As temperature increased, vitamin C loss rate increased under both packaging conditions, but the loss tate was only 50% of the LDPE film packaging rate when ON film vacuum packaging was used. In conclusion, the higher the temperature, and the greater the water content, the less vitamin C was inactivated during extrusion cooking, although the loss rah of vitamin C became faster as temperature and water content rose. In conclusion, extrusion process could be applied for making vitamin C matrix to extend vitamin C preservation.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.11a
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• pp.215-218
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• 1998

The thermal stability of polyaniline-camphorsulfonic acid(PANI-CSA) film was studied as a function of temperature and time. A decrease in electrical conductivity of PANI-CSA film occurred when PANI-CSA film is subjected to temperature above 60$^{\circ}C$. From the result of thermogravimetry (TG), it was thought that the deterioration in electrical conductivity of PANI-CSA film was due to evaporation of water and residual solvent.