• Elastomers and Composites
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• v.15 no.1
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• pp.3-9
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• 1980

The oxygen permeability and it's proofness of te various commercial polymer films have been investigated at the constant pressure and temperature. Oxygen proofness, the reciprocals of the oxygen permeability for the various samples, were determined by means of a coulometric oxygen permeability tester. The testing of sample films was performed at constant temperature $(23{\pm}1^{\circ}C)$ under 1 atm. for 24 hours. The order of the relative proofness observed are as follows; oriented Nylon (O. Nylon)> oriented Polyester (O. PET)>nonoriented Nylon (N. Nylon)>nonoriented Polyester (N.PET)> rigid Polyvinyl chloride (Rigid PVC)>semirigid Polyvinyl chloride (Semirigid PVC)> oriented Polypropylene (O. PP)>plasticized Polyvinyl chloride (P. PVC)> casted Polypropylene (C. PP)> low density Polyethylene (LDPE)>high density Polyethylene (HDPE, Inflation)> high density-polyethylene (HDPE, T-die) The oxygen proofness of the films was increased with the polarity cf polymer, the film thickness and mechanical orientation and decreased with the addition of plasticizer in PVC. For the use of wrapping materials, one film with the polar property in the main chain of the polymer molecule and the others with nonpolar property in it are laminated for the protection from oxygen and moisture.

• Food Science and Preservation
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• v.13 no.2
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• pp.125-130
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• 2006

In order to study the storage stability of winter date (Zizyphus jujuba Miller) with functional MA film storage, linear low density polyethylene $(LLDPE,\;30{\mu}m\;and\;60{\mu}m)$ film packaging and non-packaging were compared $30{\mu}m$ LLDPE packaging, $60{\mu}m$ LLDPE packaging and non-packaging samples were stored at $0^{\circ}C,\;8^{\circ}C$ (low temperature) and $25^{\circ}C$(room temperature) for 10 weeks. Weight loss of $30{\mu}m$ LLDPE packaging, $60{\mu}m$ LLDPE packaging and non-packaging in room temperature were decreased by 3.6% 0.4% and 36.1% respectively. Titratable acidity showed the trend of similarity in all treatment during the storage conditions, and especially LLDPE film packaging showed higher than non-packaging in the last storage. Soluble solids showed an increase in non-packaging, a decrease in LDPE film packaging highly. Vitamin C content showed the trend of decrease in all treatments, but non-packed jujubes sustained higher than LLDPE film packaging.

• Korean Journal of Food Science and Technology
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• v.33 no.3
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• pp.294-300
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• 2001

Effect of bean water concentration and incubation time of Yukwa paste as well as packaging method on the quality of Yukwa was investigated. Quality loss in Yukwa during storage was dependent on the packaging method such as bamboo packaging at $30^{\circ}C$, nitrogen packaging at $30^{\circ}C$ and LDPE packaging at $-18^{\circ}C$. Peroxide value increased with bean water concentration, but showed no significant difference by incubation time. The hardness of Yukwa decreased with the increase of bean water concentration, incubation time, and storage time but showed no significant difference by packaging method. Sensory evaluation after storage for 3 months showed that Yukwa color was significantly influenced by packaging method and bean water concentration. The volume was also significantly influenced by bean water concentration and incubation time. Off-flavor showed significant difference by storage method. Tenderness, taste and overall desirability showed significant difference by bean water concentration. Crispness showed significant difference by storage method and bean water concentration.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.08a
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• pp.81-81
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• 2020

본 연구는 새싹인삼(Panax ginseng sprout) 재배용으로 이용하기 위한 묘삼(종삼)의 장기 저온저장 시 사용되는 필름의 종류가 묘삼의 출아율이나 생육에 영향을 미치는 지 조사하기 위해 수행되었다. 포장에 사용된 필름은 다공성물질인 제올라이트와 페그마타이트가 5% 함유된 50㎛ low density polyethylene(기능성 LDPE) 필름과 nylon/polyethylene 80 ㎛(Ny/PE) 필름에 묘삼을 100g씩 포장한 후 골판지 상자에 담아 -2℃의 저장고에서 10개월 동안 저장하면서 8개월째부터 2개월마다 시료를 꺼내어 5℃에서 5일 동안 온도 순화를 시킨 후 1차 조사에서는 육안조사로 실험실에서 건전한 묘삼과 부패 묘삼을 조사하였고, 건전한 묘삼만 새싹인삼 수경재배 농가에 재식한 후 2차 조사로 묘삼의 출아율과 출아된 묘삼이 새싹인삼으로 건전하게 생육한 비율을 조사하였다. 조사결과 Ny/PE 필름에 8개월 저장된 묘삼의 경우 1차 육안검사 시 뇌두부위가 검게 변하여 묘삼이 대부분 고사된 것으로 조사되었다. 필름 개봉 전 필름 내부의 O₂ 및 CO₂ 가스농도를 측정한 결과 O₂ 농도는 1.91%, CO₂ 농도는 38.9%로 측정되었고, 필름 개봉 시 알코올 냄새의 이취가 나는 것으로 보아 Ny/PE 필름으로 포장 된 묘삼이 -2℃의 저온저장기간 동안에도 호흡을 하면서 필름 내 산소를 완전히 소모하고 혐기적인 환경으로 변화시켜 대사활동이 불가능하였기 때문에 뇌두의 싹이 고사된 것으로 조사되었다. 반면 기능성 필름으로 포장한 묘삼은 저장 8개월에 정식 후 74.3%의 출아율을 보였고, 건전한 새싹인삼의 비율은 67.2%로 조사되었다. 정식 전·후 묘삼의 개체수 대비 건전 출아율의 비율은 56.7%를 나타내어 Ny/PE 필름으로 포장한 묘삼의 결과와 큰 차이를 보였다. 기능성필름의 개봉 전 필름 내부의 O₂ 및 CO₂ 가스농도를 측정한 결과 O₂ 농도는 12.9%, CO₂ 농도는 4.6%로 측정되어 묘삼의 저온저장 시 필름을 적용할 경우 공기의 유동이 원활이 이루어져 내부 O₂ 농도를 일정 수준 이상 유지해주는 필름을 사용하는 것이 묘삼의 출아와 생육에 좋은 것으로 조사되었다.

• Journal of Applied Biological Chemistry
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• v.57 no.4
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• pp.325-329
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• 2014

To maintain the quality of sweet persimmon during storage, the samples were treated with a combination of 50 ppm $ClO_2$ and 0.1% fumaric acid after harvest, packaged with low density polyethylene film, and stored at $1{\pm}1^{\circ}C$ for 35 days. The combined treatment reduced the populations of total aerobic bacteria, yeast and molds by 1.82 and 2.07 log CFU/g, respectively, compared to the control. During storage, hardness of all samples decreased, but total soluble solids and weight loss were not significantly different among treatments. In addition, high-quality dehydrated sweet persimmon was prepared using red algae extract as a dehydrating agent. The rehydration ratio and vitamin C content of red algae extract-treated sample were greater than those of hot-air dried sample. These results suggest that the combined treatment of $ClO_2$ and fumaric acid can be useful for maintaining microbiological safety of sweet persimmon during storage and dehydration of sweet persimmon slices using red algae extract is an efficient drying method for the preparation of high-quality dehydrated sweet persimmon.

• Korean Journal of Food Science and Technology
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• v.34 no.6
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• pp.1036-1042
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• 2002

During storage at $25^{\circ}C$, the effect of gas absorbents, such as carbon dioxide scavenger, ethylene absorber, and their combinations, on respiration characteristics and quality attributes of mature-green Mume fruits packaged in $30\;{\mu}m$ low density polyethylene (LDPE) film was examined. Changes in quality attributes of the fruits were observed in terms of weight loss, titratable acidity, pH, fish firmness, color, water-soluble solid, and chlorophyll contents. In the presence of ethylene absorber $(KMnO_4)$, the physiological injury was remarkably suppressed, and there was no significant injury in Mume fruits at $25^{\circ}C$ for 10 days. Yellowing and softening were also noticeably reduced by the combination of plastic film packaging and inclusion of ethylene absorber. The respiration rate was slower in fruits sealed with ethylene absorber than in those with absorbent-free packaging. Using ethylene absorber, levels of oxygen and carbon dioxide were maintained at 2-3 and 7-8%, respectively, during storage at $25^{\circ}C$ for 10 days. The addition of carbon dioxide scavenger $(Ca(OH)_2)$, negatively affected the quality attributes and respiration characteristics of the fruits. Overall results showed that ethylene removal by gas absorbent in the film packages significantly prolonged the shelf life of the fruits at ambient temperature.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.28 no.2
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• pp.105-113
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• 2022

Mulching film was produced by LDPE and LLDPE adding biomass byproducts and MA(maleic anhydride), talc/clay/CaO/CaCO₃. And also surveyed to tensile strength, elongation, TGA and DSC according to the UV irradiation time. The tensile strength and elongation showed 20 N/cm² and 5% after UV irradiation 100 hours, and those was nearly 0 N/cm² and 0% after 200 hours, respectively. TGA of film was showed to peak of polymer itself, and DSC was slightly higher than that of initial value. At the pilot scale test, we were able to see the differentiate of degradation between control and developed film after 12 weeks, and also torn off at several part of mulching film. The degradation of mulching film after growing corn showed similar to a pilot scale test. Above the results, the developed mulching film adding biomass will be to used for agricultural farming.

• Korean Journal of Plant Resources
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• v.19 no.1
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• pp.59-67
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• 2006

This study was conducted to investigate the changes in some physicochemical properties, including pH, moisture and ash content, Ca, Na, Mg, K, crude saponin and codonoposide, of cultivated Codonopsis lanceolata, which were packed with woven polypropylene(WP) or low density polyethylene(LDPE, thickness 0.04 mm) bag and stored at $4^{\circ}C\;or\;20^{\circ}C$ for 30 days. pH of the juice of fresh Codonopsis lanceolata was 5.3 and decreased significantly during storage. Storage temperature exerted more influence upon the content of moisture and ash than package materials. The concentration of Ca, Mg, Na and K were 427.3mg, 203.4mg, 10.2mg, and 619mg per 100g dry matter respectively. The contents of Ca and Na were not changed significantly, but the contents of Mg and K were decreased during room temperature storage. It was revealed that the juices of stored sample had darkened and redness and yellowness were somewhat deeper than those of fresh sample. 1g of the cultivated Codonopsis lanceolata had 29.3mg of crude saponin and 3.78mg of codonoposide, and the changes of them during storage at various conditions were not significant.

• Food Science and Preservation
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• v.19 no.1
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• pp.67-73
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• 2012

This study was carried out to investigate the packaging status of the $Agaricus$ $bisporus$ mushrooms and the benefits of storing them after precooling to improve their distribution system using small packages. The packaging status of the $Agaricus$ $bisporus$ mushrooms was surveyed at a farm, a department store, a wholesale market, and a supermarket from May to September 2011. The packaging materials that were used were PS, carton, PP, LDPE, PLA, and PVC. The harvested $Agaricus$ $bisporus$ mushrooms were precooled at $4^{\circ}C$ for three hours and were then stored at $20^{\circ}C$ for three days. The weight loss rate of the precooled sample was slightly lower than that of the unprecooled sample; conversely, the L value of the precooled sample was higher than that of the unprecooled sample. The ${\Delta}E$ value was lowest in the precooled sample after packaging. The precooling process effectively prolonged the shelf life and enhanced the quality of the$Agaricus$ $bisporus$ mushrooms.

• International Journal of Highway Engineering
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• v.2 no.4 s.6
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• pp.101-109
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• 2000

This study was performed to estimate fatigue life of polymer-modified and reinforced overlay asphalt mixtures with respect to reflection cracking in asphalt overlay pavement. In order to achieve the goal, the expedited reflection cracking test method was developed and applied to various mixtures and the results were compared one another with respect to the resistant characteristics of reflection cracking. The theoretical prediction equation of fatigue life for each mixture was suggested based on statistical analysis of experimental test results in the flexural failure mode. Since coefficients of correlation between estimated values and measured values were very high ($r^2=0.95$ or higher), the prediction model can be used for relative comparison of various pavement overlay choices to be used in the field.