• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.19 no.1
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• pp.29-33
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• 2013

This study investigated the effect of films treated with anti-fogging (LA) agent on the freshness extension of 'Fuji' Apples. Preference, weight loss, total ascorbic acid, sugar content, acidity, change of gas composition in package were evaluated during storage at $15^{\circ}C$. After 150 days of storage, the weight loss of apples in control (L), LA was 1.0 to 1.1%. Total ascorbic acid content of apples in control after 150 days was 2.09 mg/100g F.W, that of apple in LA was 2.47 mg/100g F.W. The titratable acidity of apple in LA was lower than that in control, while soluble solids content of LA was higher than that in control after 150 days. Ethylene gas adsorbability in control package was 192.2 ppm and that in LA was 195.7 ppm. It was verified that LA treated with anti-fogging agent are few different compare to control, but commerdity on the display in market was considered higher than that of non-treated anti-fogging agent.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.27 no.3
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• pp.169-174
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• 2021

Today, plastic waste has become a critical social issue due to the increasing of plastic consumption. Korean annual per capita plastic consumption was 132 kg, the most plastic consuming country in the world. Internationally, Carbon Neutral Agreement is underway due to global warming, consumers' interest and needs for biomass-based plastics has also been increased. In this study, film was produced by adding composite use additives to the biomass-based plastics according to concentration, and the resulting changes in discharge volume, melt index, and tensile strength were investigated. Melt index (MI) was significantly higher in PLA and PBAT than in petroleum-based resin LLDPE and LDPE. Also, among the same resin or in the same treatment group, MI has been increased when the heating temperature is increased. The discharge volume and gravity of the BDP-2 to which 4% compatibilizer was added were found to be higher among all treatments, while the tensile strength of MD and TD was also higher. BDP-2 was suitable to the film producing methods for biodegradable film production.

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.171-172
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• 2002

나노미터 규모의 작은 충전제 입자는 마이크로 미터 규모의 일반적인 충전제 입자에 비해서 많은 다른 점이 발견되어 왔다. 이 연구에서는 최근에 알게된 입경이 100nm 이하인 ZnO 입자가 radical 중합된 고분자의 열안정성을 향상시키는 현상을 보다 자세하게 연구한 것이다. HDPE, LDPE, LLDPE, PP 및 PS를 열분해가 아주 느리게 일어나는 낮은 RPM으로 Haake사의 Torque Rheometer의 internal mixer 안에서 녹인 후 평균입경 49nm인 ZnO 나노입자를 약4분간 충부히 분산되도록 혼합하고 50 RPM으로 혼합속도를 높여서 시간에 따른 Trque의 변화를 측정하므로써 열안정성 효과를 관찰하였다. (중략)

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.236-239
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• 2001

In this study, the compound materials of GRT/plastics (HDPE, LLDPE, LDPE, PP and PS) were developed. Their tensile strength, strain at yield and flexural modulus according to the change in CRT content were measured. And, the physical properties of the compound materials that the GRT content was changed in the waste vinyl HDPE and pure HDPE were measured, compared and analyzed. If tile GRT is added to PE plastics, the physical properties were superior to those of PP and PS, and in the case of HDPE, the waste vinyl HDPE had superior physical properties by the GRT content to the pure HDPE.

• Preventive Nutrition and Food Science
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• v.6 no.2
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• pp.112-116
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• 2001

Oxidized potato starch/polyethylene (PE) cast films were prepared with different percentages of linear low density PE (LLDPE), oxidized potato starch and prooxidant. For the determination of biodegradability of the films, lignocellulose-degrading Streptomyces viridosporus T7A (ATCC 39115) was used. Films were chemically disinfected and incubated with S. viridosporus by shaking at 100 rpm at 37$^{\circ}C$ for eight weeks. Hydroxyl indices of the films by Fourier-Transform Infrared Spectroscopy, mechanical Properties of the films by Instron and film morphology by scanning electron microscope (SEM) were measured. The hydroxyl index of the film containing the oxidized potato starch incubated with S. viridosporus T7A was higher than that of the corresponding control. All the films containing 5% and 10% oxidized starch showed a decrease of tensile strength on the films after incubation when the corresponding uninoculated film was compared. In the oxidized starch/PE film incubated with S. viridosporus T7A, partial destruction of starch and PE was examined by SEM.

• Journal of Food Hygiene and Safety
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• v.14 no.2
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• pp.134-139
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• 1999

The relationship between storage stability and chlorophyll contents of dried laver(DL), roasted laver(RL) and roasted seasoned laver(RSL) according to packaging during storage at 20$\pm$0.5$^{\circ}C$ were investigated by measuring the acid value(AV) and the peroxide value(POV). There results are as follows; 1.The storage stability was decreased in the rank of 0 < 3< 6 < 9 months by storage term, RL < DL < RSL by the kind of laver products and PP/PE/AL/PE/LLDPE(Al) < PP/PE(PP) y packaging. 2. When the silica gel was added to RSL, the storage stability was improved. The more the addition level of silica gel was increased, the more the storage stability was improved. The rank order was 2g < 4g in RSL. 3. Reduction of the total chlorophyll content in RSL were deacreased to 10% when packed with Al and 24% when packed with PP.

• KIEE International Transactions on Electrophysics and Applications
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• v.3C no.4
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• pp.146-154
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• 2003

This paper describes various characteristics of the new compounds for cable jackets and model cables advanced in waterproof performance in order to essentially solve the problems of underground (URD) distribution class power cable failures. Several compounds were manufactured by the inclusion of additives to base resins available in Korea and tested for basic property, mechanical and electrical characteristics. Two model cables were created by using the compounds determined in the test as being the most appropriate for new structured model cable jacket material. The waterproof performance and mechanical strength of the new cable jackets were verified by applicable tests. As a result, MDPE and LLDPE compounds were superior as cable jackets in both mechanical and electrical characteristic aspects when compared with conventional PVC. In addition, the model cables composed of the new compounds based on MDPE showed good quality results in the water permeability test.

• Carbon letters
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• v.1 no.1
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• pp.1-5
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• 2000

The effect of surface free energy on the positive temperature coefficient (PTC) of carbon black/thermoplastic resin composites was investigated. The thermoplastic resins such as EVA, LDPE, LLDPE and HDPE were used with the addition of 30 wt.% of the carbon black. The surface free energy of the composites was studied in the context of two-liquid contact angle measurements, i.e., deionized water and diiodomethane. It was observed that the resistivity on PTC composites Was greatly increased near the crystalline melting temperature, due to the thermal expansion of polymeric matrix. From the experimental results, it was proposed that the decrease of surface free energy induced by interactions between carbon black surfaces and polymer chains is an important factor to the fabrication of a PTC composite made of carbon black and polymeric matrix.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.552-555
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• 1999

In this paper, the volume resistivity properties due to mixture ration of linear low density polyethylene(LLDPE) and ethylene vinyl acetate(EVA) are studied. Electrodes is composed of upper electrode 37(mm $\Phi$), guardring electrode(inner 55(mm $\Phi$ ), and lower electrode 87(mm $\Phi$ In order to measure the leakage current, We used electrometer and stable oven with temperature controller. Measurement method is to measure the leakage current of next specimen after applying the voltage according to 'Step Apply Methods' for ten minutes. In order to measure the volume resistivity properties, the micro electrometer is used, the range of temperature and applying voltage are 25 to 100[$^{\circ}C$] to 100[V] respectively.

• Journal of Life Science
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• v.10 no.1
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• pp.61-67
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• 2000

An experiment was conducted for extension of shelf-life of cooked squid (Todarodes pacificus) using modified atmosphere packaging. The products were packed in a Ny/PE/LLDPE (0.015/0.045/0.040 mm) laminated film with air, vacuum, CO2 gas, and N2 gas, respectively, and then stored at 5$^{\circ}C$ and 2$0^{\circ}C$. Keeping qualities of the products were investigated by measuring moisture content, H, volatile basic nitrogen (VBN), viable cell count, thiobarbituric acid (TBA) value, peroxide value (POV) and color value. Good qualities of the products stored at 5$^{\circ}C$were maintained at least 9 days, 11 days, more than 35 days and 24 days in air, vacuum, CO2 gas and N2 gas packaging products, respectively. In cases of 2$0^{\circ}C$ storage, however, the shelf-lives of all the products were only one day. The shelf-life extension of the products were observed in CO2 ga>N2 gas>vacuum>air packaging in order.