• Food Science and Biotechnology
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• v.14 no.1
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• pp.68-72
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• 2005

Moisture sorption characteristics of edible composite films were determined and compared against moisture barrier properties. Edible composite films were Z1 (zein film with polyethylene glycol(PEG) and glycerol), Z2 (zein film with oleic acid), ZA1 (zein-coated high amylose corn starch film with PEG and glycerol), and ZA2 (zein-coated high amylose corn starch film with oleic acid). Z2 film showed the lowest equilibrium moisture content (EMC), monolayer value ($W_m$), water vapor permeability (WVP), and water solubility (WS). Surface structure of Z2 was relatively denser and finer than that of other edible films. GAB $W_m$ and C values decreased, while K values increased with increasing temperature. Correlation coefficients of WS:EMC and WVP:EMC at Aw 0.75 were higher than those of WS: $W_m$ and WVP: $W_m$, respectively. EMC values at Aw 0.75 appeared useful for evaluating or predicting moisture barrier properties of edible films.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.33 no.9
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• pp.97-103
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• 2005

In this paper, effects on the heat transport limitation of heat pipe by the wick structural factors were theoretically analyzed for the sintered-copper wick heat pipe. Uniformity of particle size and sintering process were acted as dominant factors on the pore distribution and wick porosity, and small deviations of the wick thickness and the pore size greatly affected the heat transport limitations of the heat pipe. Especially, slight variations of the wick thickness, mean particle radius and capillary radius along the vapor temperatures and inclination angles remarkably changed the capillary limitation of the heat pipe.

• The Research Journal of the Costume Culture
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• v.7 no.5
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• pp.165-176
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• 1999

The purpose of this study was to evaluate the effect of various knitted fabrics of sports socks on their properties of hygiene and stability. Seventeen men\`s sports socks to represent five groups with different fiber content, knit structure, yarn fineness, and finishing were used. Properties of hygiene and stability of socks were determined. The results were as follows ; 1. Evaluation of Water, vapor and heat transport properties in socks with varing fiber content showed that cotton 100% socks had the highest drop absorbency, wickability, water absorbency and water retention. Polypropylene 100% socks had an excellent wickability and moisture permeability. Acrylic blend socks had the highest thermal resistance. 2. The greatest knit stretch and knit growth of socks having lower power were found to be with cotton 100% socks had the lowest stretch. Acrylic blend socks had a excellent stretch but low fabric growth, which could give a good fir sensation during wear. 3. The commerical antimicrobial finished socks showed excellent durability after repeated cycles of laundering. 4. Length and width shrinkages were found in all laundered samples during initial cycles due to rearrangement by mechanical relaxation. Shrinkages showed no further changes and reached equilibriums after 5 cycles. Cotton 100% or cotton blend socks showed lower dimensional stability than other socks during fabric care.

• Fisheries and Aquatic Sciences
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• v.15 no.1
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• pp.9-14
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• 2012

The objectives of this research were to improve the film-forming properties of Channel Catfish Ictalurus punctatus skin gelatin (CSG) by cross-linking with transglutaminase (TG), determine and optimize the TG reaction time, and characterize the mechanical and barrier properties of CSG edible film. Cross-linking of CSG was performed by TG for 0, 10, 20, 30, and 40 min at $50^{\circ}C$, and the reaction was confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The color and mechanical and barrier properties of edible films fabricated with CSG cross-linked with TG were characterized. Gelatin yields from the extraction ranged from 18.2% to 23.3%. SDS-PAGE exhibited dark bands at 120 and 250 kDa, indicating successful TG-mediated cross-linking. The color of CSG film was not affected by TG cross-linking. The tensile strength of CSG films cross-linked with TG decreased from 42.59 to 21.73 MPa and the percent elongation increased from 42.92% to 76.96% as reaction times increased from 0 to 40 min. There was no significant difference in water vapor permeability of CSG films.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.192.1-192
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• 2003

The aim of this study was to develop a model that could be used in the design of modified atmosphere packaging (MAP) for Mandarin oranges. Respiratory data at 5, 10, 20$^{\circ}C$ for mandarin oranges were gathered and altered for create useful respiration model. The maximum rate of oxygen uptake increased with increasing temperature. The packaging materials were conventional low density polyethylene and polypropylene with anti-fog, and anti-fungi treatments, and thickness was 30 $\mu\textrm{m}$ and 50 $\mu\textrm{m}$. Permeability tests were performed to find their oxygen, carbon dioxide, water vapor transmission rate as increases in temperature. Test results were then converted to logarithm format for MAP modeling. Optimum gas composition in the package system for fruits were set according to literature and upper or lower limits of oxygen and dioxide established. To predict gas composition at certain storage time, weight of fruits, film thickness, film type, and other variables, respiration rate was studied at various storage conditions. The validity of the model was tested experimentally by observing actual atmospheric changes inside packages. It is concluded that the strategy developed is of use in designing dynamic gas exchange MAP systems, and also has potential uses in similar agricultural products.

• Fashion & Textile Research Journal
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• v.8 no.3
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• pp.363-369
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• 2006

In this the study, Lyocell fabrics for blanket were developed to get high value added goods for elder and Infant. Therefore, the purpose of the study was determine the effect of twist per inch on the physical properties of developed fabrics, including compression property and abrasion resistance on the process for making Lyocell combined yarns. For comparison, commonly used cotton blanket was used. The results were as the follows: 1) Dimensional changes of Lyocell fabrics was in -3% which value was pretty stable, and antistatic property was very good with 10V of electric propensity voltage which means there was no static electricity at all. Pilling property of Lyocell fabrics showed 3 grade which was good and air permeability and moisture vapor transmission rate of Lyocell fabrics were higher than those of cotton fabric and keeping warmth rate of Lyocell fabrics was about 50% which means it very warms. 2) Twist per inch of Lyocell combined yarns increased with tensile strength and elongation of Lyocell fabrics. 3) Twist per inch of Lyocell combined yarns increased with decreasing thickness reduction rate and therefore, compression property of those was pretty good. Specially, compression property of Lyocell fabrics made with yarns of 3.9TPI was better than those of cotton fabric. 4) Twist per inch of Lyocell combined yarns increased with abrasion resistance of Lyocell fabrics.

• Journal of the Korean Society for Heat Treatment
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• v.25 no.2
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• pp.65-73
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• 2012

The Gas Diffusion Layer (GDL) of fuel cell, are required to provide both delivery of reactant gases to the catalyst layer and removal of water in either vapor or liquid form in typical PEMFCs. In this study, the fabrication of GDL containing Micro Porous Layer (MPL) made of the slurry of PVDF mixed with carbon black is investigated in detail. Physical properties of GDL containing MPL, such as electrical resistance, gas permeability and microstructure were examined, and the performance of the cell using developed GDL with MPL was evaluated. The results show that MPL with PVDF binder demonstrated uniformly distributed microstructure without large cracks and pores, which resulted in better electrical conductivity. The fuel cell performance test demonstrates that the developed GDL with MPL has a great potential due to enhanced mass transport property due to its porous structure and small pore size.

• Journal of Soil and Groundwater Environment
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• v.10 no.2
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• pp.35-43
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• 2005

Bioslurping combines the three remedial approaches of bioventing, vacuum-enhanced free-product recovery, and soil vapor extraction. Bioslurping is less effective in tight (low-permeability) soils. The greatest limitation to air permeability is excessive soil moisture. Optimum soil moisture is very soil-specific. Too much moisture can reduce air permeability of the soil and decrease its oxygen transfer capability. Too little moisture will inhibit microbial activity. So Modified Fenton reaction as chemical treatment which can overcome the weakness of Bioslurping was experimented for simultaneous treatment. Although the diesel removal efficiency of SVE process increased in proportion to applied vacuum pressure, SVE process was difficulty to remediation quickly semi- or non-volatile compounds absorbed soil strongly. And SVE process had variation of efficiency with distance from the extraction well and depth a air flow form of hemisphere centering around the well. Below 0.1 % hydrogen peroxide shows the potential of using hydrogen peroxide as oxygen source but the co-oxidation of chemical and biological treatment was impossible because of the low efficiency of Modified Fenton reaction at 0.1 % (wt) hydrogen peroxide. NTA was more efficiency than EDTA as chelating agent and diesel removal efficiency of Modified Fenton reaction increased in proportion to hydrogen peroxide concentration. Hexadecane as typical aliphatic compound was removed less than Toluene as aromatic compound because of its structural stability in Modified Fenton reaction. What minimum 10% hydrogen peroxide concentration has good remediation efficiency of diesel contaminated groundwater may show the potential use of Modified Fenton reaction after bioslurping treatment.

• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.452-459
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• 1997

Effect of extraction pH on mechanical properties such as tensile strength (TS) and elongation (E) and on water vapor permeability (WVP) of soybean protein isolate (SPI) edible films extracted from soybean meal was investigated. Five pHs, acidic range (pH 2.0 and pH 3.0), neutral range (pH 7.0) and alkalic range (pH 10.0 and 12.0), were used to extract SPI. TS of the film extracted at pH 7.0 was the lowest, and WVP of $SPI_3$ (SPI extracted at pH 3) film was the lowest value among the films. The WVP of $SPI_3$ films was $3.349\;{\times}\;10^{-10}\;g{\cdot}m/m^2{\cdot}s{\cdot}Pa$ and increased to $3.871\;{\times}\;10^{-10}\;g{\cdot}m/m^2{\cdot}s{\cdot}Pa$ as film thickness increased from $55\;{\mu}m$ to $72\;{\mu}m$ thickness. Three different plasticizers (glycerol, polyethylene glycol and propylene glycol) were used for $SPI_2$ (SPI extracted at pH 2) film. TS of $SPI_2$ films was 12.297 MPa and decreased to 1.356 MPa for glycerol and showed the same trend in other two plasticizers. The SPI films extracted at acidic range were shown higher mechanical properties and lower water vapor permeabilities than those of extracted at neutral and alkalic ranges. The difference of SPI film properties seemed to be attributed by 11S/7S ratio as well as protein content.

• Korean Chemical Engineering Research
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• v.52 no.4
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• pp.530-537
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• 2014

Moisture is a major factor causing the deteriorative physical change, microbial growth, and chemical reaction of the products. In this study, the moisture absorbing composite films have been prepared with moisture absorbing material of polyacrylic acid partial sodium salt (PAPSS) impregnated on LLDPE polymer for the functional packaging applications. The results showed that PAPSS impregnated film illustrated uniformly dispersed PAPSS particles in the LLDPE polymer matrix. The transparency of the PAPSS impregnated film decreased slightly at higher PAPSS concentrations. An increase in the PAPSS content for moisture-absorbing films showed a similar decrease in tensile strength, percent elongation at break, and tear strength. Their values of films impregnated with PAPSS of 0.5, 1, and 2% showed no significant difference. Meanwhile, 4% PAPSS films significantly decreased the values of mechanical properties compared to the films impregnated with different PAPSS levels. Values of the oxygen permeability and water vapor permeability for PAPSS impregnated films decreased significantly with greater PAPSS. The results indicate that 4% PAPSS impregnated in LLDPE films had high affinity of moisture absorbencies compared to the other films. The mathematical equation that best described the moisture sorption isotherm of each film sample was the GAB equation at $25^{\circ}C$. The crystallization and melting temperatures of PAPSS films were influenced by the addition of PAPSS material, but showed good thermal stability.