• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.4
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• pp.355-362
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• 1983

A vacuum-packed seasoned-dried product of sea mussel, Mytilus edulis, caught in the southern coasts of Korea, was prepared and stored at $35^{\circ}C$ for 70 days to test quality stability. Sea mussel, purchased from Jagalchi fish market in Busan, was steamed, shucked and eliminated byssus. The sea mussel meat was seasoned with the seasoning solution prepared with sugar, salt, sorbitol, glycerol, monosodium glutamate, 5'-ribonucleotide and smoke flavor (Smoke-EZ, Alpha Foods Co., Ltd.). After seasoning, the meat was dried at $52-58^{\circ}C$ for three hours, vacuum-packed in the laminated plastic film bag($14{\times}15cm$), and finally sterilized at $120^{\circ}C$ for 26 minutes in hot water circulating retort. The moisture, water activity, color value(L, a and b value), texture, TBA value and viable bacterial count of the products were determined during the period of storage at $35^{\circ}C$. From the results obtained, it became clear that the product could be preserved in a good quality for 70 days at $35^{\circ}C$, though a slight decrease in moisture content and development of a pale brown color was resulted. Judging from the sensory evaluation on flavor, the products containing smoke flavor were most desirable.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2005.06a
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• pp.32-39
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• 2005

When PFC(Perfluorocarbonate) decontamination technology is applied to removal of radioactive contaminated particulate adhered at surface during the operation of nuclear research facilities, it is necessary to develop a filtration equipment to reuse of PFC solution due to high price, also to minimize the volume of second wastewater. Contaminated characteristics of hot particulate was investigated and a filtration process was presented to remove suspended radioactive particulate from PFC decontamination wastewater generated on PFC decontamination. The range of size of hot particulate adhered at the surface of research facilities measured by SEM was $0.1{\sim}10{\mu}m$. Hot particulate of more than $2{\mu}m$ in PFC contamination wastewater was removed by first filter and then hot particulate of more than $0.2{\mu}m$ was removed by second filter. Results of filter experiments showed that filtration efficiency of PVDF(Poly vinylidene fluoride), PP(Polypropylene), Ceramic filter was $95{\sim}97\%$. A ceramic filter showed a higher filtration efficiency with a little low permeate volume. Also, a ceramic of inorganic compound could be broken easily on experiment and has a high price but was highly stable at radioactivity in comparison of PVDF and PP of a macromolecule which generate $H_2$ gas in alpha radioactivity environment.

• Journal of Adhesion and Interface
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• v.16 no.1
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• pp.29-34
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• 2015

Hydrocarbon resins, which are defined as low molecular weight, amorphous, and thermoplastic polymers, are widely used as tackifier for various types of adhesives, as processing aids in rubber compounds, and as modifiers for plastics polymers such as isotactic polypropylene. Typically, hydrocarbon resins are non-polar, and thus highly compatible with non-polar rubbers and polymer. However, they are poorly compatible with polar system, such as acrylic copolymer, polyurethanes, and polyamides. Moreover, recently the raw materials of hydrocarbon resin from naphtha cracking had been decreased because of light feed cracking such as gas cracking. To overcome this problem, in this study, novel hydrocarbon resins were designed to have a highly polar chemical structure which material is sustainable. And, it was successfully synthesized by Diels-Alder reaction of dicyclopentadiene monomer and sorbic acid from blueberry as renewable resources. Acrylic resins were formulated with various tackifiers solution including sorbic acid grafted hydrogenated dicyclopentadiene hydrocarbon resins in acrylic adhesive and rolling ball tack, loop tack, $180^{\circ}$ peel adhesion strength, and shear adhesion strength were measured. The properties depend on the softening point and polar content of tackifiers.

• Food Science and Preservation
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• v.21 no.4
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• pp.473-482
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• 2014

Changes in quality of mushroom during storage are severe problem that reduce the shelf life of harvested mushrooms. This study investigates the effect of oriental melon peel extracts on maintenance of the quality of mushrooms (Agaricus bisporus). Mushrooms were dipped in solutions (distilled water, DW; 0.1% oriental melon peel extract, OMP; 0.1% ascorbic acid, AA; and OMP+AA) for 3 minutes. After the dipped mushrooms were air-dried at room temperature, they were packaged in a polypropylene (PP) films and stored at $4^{\circ}C$ and $15^{\circ}C$. The changes in the quality of mushrooms were measured in terms of their color, gas composition, firmness, and sensory evaluation during storage at $4^{\circ}C$ and $15^{\circ}C$. The antioxidant and anti-browning activities of oriental melon peel extract were measured with respect to their total polyphenol contents, total flavonoid contents, DPPH, ABTS radical scavenging, copper chelating activity and PPO inhibition activity. The samples that were dipped in all the solutions did not show significant differences in firmness and gas exchange during their storage at $4^{\circ}C$ and $15^{\circ}C$. At both storage temperatures, the OMP solution samples showed highest L value and lowest delta E value. The sensory evaluation showed that during the storage period, the overall acceptability of mushrooms treated with the OMP and OMP+AA solutions was higher than that of the untreated mushrooms. The total polyphenol and flavonoid contents of oriental melon peel extract were $4.81mg\;GAE{\cdot}g^{-1}$ and $1.18mg\;QE{\cdot}g^{-1}$, respectively. The DPPH, ABTS radical scavenging activity, copper chelating activity and PPO inhibition activity of the oriental melon peel extract lower than ascorbic acid. All these results suggest that oriental melon peel extract can be used as a natural browning inhibitor.

• Journal of Navigation and Port Research
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• v.46 no.4
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• pp.297-302
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• 2022

An exothermic oil absorbent sheet with calcium chloride crystals can be fabricated, by dipping a clean polypropylene fabric in calcium carbonate and hydrochloric acid solution and drying it. The exothermic oil absorbent sheet applied to the seawater surface, releases heat by the dissociation of calcium chloride. The dissociation heat liquefies the solidified low-sulfur fuel oil at a low temperature, and converts it to a state at which it can be absorbed. The optimum mole concentrations of calcium carbonate and hydrochloric acid required for the exothermic oil absorbent sheet, are 0.25 M and 0.5 M, respectively. The oil absorption capacity of the exothermic oil absorbent sheet for low sulfur fuel oil depends on the seawater temperature. But, it is highly excellent at 4.5-7.08 g/g at 10℃, the average seawater temperature during the winter in Korea. The exothermic oil absorbent sheet is an excellent alternative in absorbing low-sulfur fuel oil in winter and removing it from seawater.

• Journal of Chest Surgery
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• v.36 no.2
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• pp.63-72
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• 2003

Although a variety of synthetic vascular grafts are available in modern vascular surgery, no ideal prosthesis ha,4 yet been developed. Small-caliber vascular grafts with low flow, as used in the lower extremity, continue to become thrombosed at unacceptable rates. We have developed and evaluated the new antithrombogenic blood contacting surfaces in canine model. Material and Method: Two now antithrombogenic blood contacting surfaces(Polyvinylalcohol -Polyurethane(PVA-PU) blend and natural Graphite-polyurethane(G-PU) blend) have been developed and evaluated in canine model, using vascular grafts and patches. The luminal surfaces of the test vascular grafts(5 mm ID) were fabricated by dipping a glass rod in PVA-PU blend solution(50 % PVA) using phase separation method. Mongrel dogs of either sex weighing 18-22 kg were anesthetized by endotracheal intubation using halothane and their lungs were ventilated with a volume-cycled ventilator, Maintenance anesthesia with 0.5-1.0% halothane and supplemental oxygen was used. Two pairs were used for comparison in the bilateral femoral arteries for both vascular grafts(PVA-PU vs. PU) and vascular patches(G-PU vs. PU). Bilateral groin incisions were made and the arteries were exposed and clamped. After an excision of 1 cm of the artery between clamps, a grail of 2.5 cm in length was implanted end-to-end using 6-0 polypropylene suture. The vascular patch was implanted as a form of on-lay patch. Animals were sacrificed at 1, 2, 4, 6, 8 and 16 weeks for vascular grafts and 1, 2. 4 and 6 weeks for vascular patches. Result The vascular grafts of PVA-PU blends showed patent lumina in the 2 and 16 weeks animals, while those of PU showed a patent lumen in 2 weeks animal. PVA-PU graft of 16 weeks showed a fairly clean luminal surface. A light microscopic finding of this graft demonstrated good tissue infiltration through porosity, The animals with vascular patches showed patent arteries in both groups except 2 weeks animal. Scanning electron microscopy of the luminal surfaces of G-PU patches in 4 and 6 weeks animals showed endothelial cell covering with microvilli. PU patches showed qualitatively less endothelial cell covering. Conclusion: In conclusion, PVA-PU and G-PU blends can be a promising blood contacting surfaces for application in a synthetic vascualr graft. However, further animal study is needed to determine the real long-term effects of these methods of surface modifications.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.29 no.3
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• pp.153-161
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• 2023

The worldwide effects of COVID-19 have led to a surge in online shopping and contactless services. The consumption pattern has caused the issues such as the environmental pollution together with the increase of plastic waste. Reducing the reliance on the petroleum based plastic use for the package and replacing it with environmentally friendly material are the simple ways in order to solve those problems. Paper is an eco-friendly product with high recyclability as the food packaging materials but has still poor barrier properties. A barrier coating on surface of the paper can be achieved with the proper packaging materials featuring water, gas and grease barrier. Polyethylene (PE) or polypropylene (PP) coatings which are generally laminated or coated to paper are widely used in food packaging applications to protect products from moisture and provide water or grease resistance. However, recycling of packaging containing PE or PP matrix is limited and costly because those films are difficult to degrade in the environment. This study investigated the recyclability of modified acrylic emulsion coating papers compared to PE and PP polymer matrixes as well as their mechanical and gas barrier properties. The results showed that PE or modified acrylic emulsion coated papers had better mechanical properties compared to the uncoated paper as a control. PE or PP coating papers showed strong oil resistance property, achieving a kit rating of 12. Those papers also had a significantly higher percentage of screen reject during the recycling process than modified acrylic coated paper which had a screen rejection rate of 6.25%. In addition an uncoated paper had similar value of a screen rejection rate. It may suggest that modified acrylic emulsion coating paper can be more easily recycled than PE or PP coating papers. The overall results of the study found that modified acrylic emulsion coating paper would be a viable alternative to suggest a possible solution to an environmental problem as well as enhancing the weak mechanical and poor gas barrier properties of the paper against moisture.