• Journal of the Korean Electrochemical Society
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• v.7 no.3
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• pp.148-154
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• 2004

Ammonium ion selective electrodes have been prepared using nonactin as an ionophore and poly(vinyl chloride) (PVC) or polyurethane(PU) as a polymer matrix with or without a plasticizer, bis(2-ethylhexyl) adipate, and their performances have been evaluated. The reults indicate that PU-based electrodes can be designed to perform better although PVC-based electrodes generally show better performances. In efforts to explain the obervation, we also carried out atomic force microscopy as well as impedance studies, and the results suggests that islands of ion-ophores are formed in the PVC membranes through which ion transfers appear to be more facile than through the PU membranes. The PU membranes appear to have ionophores better dispersed throughout the film and are more resistive to ion mobilities in comparison to PVC films.

• Korean Journal of Materials Research
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• v.3 no.4
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• pp.388-394
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• 1993

The state of aggregation and optical contrast of poly(vinyl chlorich, )(PVC)!nematic liquid crystal(LC) composite film liave been studied for a wide range(30~70 wt% LC)of film composition. In addition. effects of temperature, frequency and voltage of the applied AV electric field on the film transmittance have heen measured for a film containing (6O wt % I, C, which showed maximum optical contrast. For this particular composition of film, tlw thn'shold voltage was smalkr than .40$V_{p-p}$ at I kHZ, $25^{\circ}C$, and the rise time and decay time were smalle, r than l0Oms at 100$V_{p-p}$, I kHz, and $25^{\circ}C$.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.05a
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• pp.905-906
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• 2012

In this paper, we develope new goods for helping of increasing income that tube arched POP by using PVC papers to PET plating films. General market is supported with high quality POP by using specified goods and increased value of goods. Also, it is easily developed with new material with re-combination of existing materials. The purpose of this paper is that good design and materials of POP spreads widely not only big markets but also small shops.

• Polymer(Korea)
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• v.35 no.6
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• pp.615-618
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• 2011

Carbon nanotubes (CNTs) draw attention as promising materials due to their excellent electrical and mechanical properties. However, the intrinsic strong interaction between CNTs presents a challenge to their use in various applications. Here, we present a facile method to disperse single-walled carbon nanotubes (SWCNTs) in a polar solution using a graft copolymer, poly(vinyl chloride)-graft-poly(oxyethylene methacrylate), PVC-g-POEM. The graft copolymer was synthesized via atom transfer radical polymerization (ATRP), as confirmed by gel permeation chromatography (GPC) and $^1H$ NMR spectroscopy. The SWCNTs were uniformly dispersed in a polar solvent such as dimethylsiloxane (DMSO) using PVC-g-POEM as a dispersant, due to interaction between CNT and the graft copolymer, as revealed by transmission electron microscopy (TEM) analysis. Upon removal of the solvent, free standing nanocomposite films with good homogeneity were obtained.

• Korean Journal of Food Science and Technology
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• v.30 no.5
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• pp.1140-1145
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• 1998

Low density polyethylene (LDPE) films incorporated with 1% antimicrobial agents of Rheum palmatum extract, Coptis chinensis extract, and Ag-substituted inorganic zirconium matrix, were applied to modified atmosphere packaging of 200 g fresh strawberries. Plain LDPE film package, PVC wrap and perforative pinhole package of the film impregnated with 1% Rheum palmatum extract were also constructed for comparative purpose. All the packages were stored for 13 days at $5^{\circ}C$ and measured in package atmosphere, microbial count and quality attributes of the strawberry fruits. The antimicrobial LDPE films retarded the growth in total aerobic bacteria, lactic acid bacteria and yeast on the fruits, and resulted in significantly lower decay. The degrees of reduced microbial growth and fruit decay in the antimicrobial film packages were more pronounced, when applied by hermetical sealing to produce the modified atmospheres of low $O_2$ (<4.0%) and $CO_2$ concentrations with $6.3{\sim}9.0%$. The hermetically sealed packages of antimicrobial LDPE films also showed better retention of fruit firmness and did not give any negative effect on the physical and chemical qualities of strawberries.

• Food Science and Preservation
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• v.1 no.2
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• pp.93-98
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• 1994

Fresh ginseng was packed by using available commercial plastic films of polyvinyl chloride (PVC), cast polypropylene (CPP) and low density polyethylene (LDPE). PVC was used as a wrapping on polystyrene tray, and CPP and LDPE were applied as pouch packages. Gas composition of the package and keeping quality of ginseng in the packages were evaluated for 20 day storage at 5$^{\circ}C$. LDPE (27$\mu\textrm{m}$ thick) Package modified the Package atmosphere to 11.7% O2 and 2.1% CO2, gave low microbial growth and good sensory score after 20 day storage.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.05a
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• pp.77-77
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• 2015

Metallic glass alloys having dense packing structure have short range ordered structure with long range homogeneity. Therefore, they can provide complete corrosion protection and unique electrical properties. Recently, metallic glass thin films have received much attention to extend its application fields combining with PVC coating technologies. The metallic glass thin films can change the surface properties of the conventional bulk materials which need anticorrosion properties. However, multi-component alloying targets are required to fabricate the metallic glass thin films because metallic glass alloys contain more than three elements. Recently, many researchers have been reported the properties of the metallic glass thin films synthesized with multi-cathode systems or amorphous target. But, it is difficult to fabricate the large sized sputtering targets for mass production equipment with high toughness and thermal stability. In this study, newly developed sputtering target with glass forming ability and the properties of the metallic glass thin films will be introduced with respect to the various application fields such as bipolar plate in PEM fuel cell and decorative coatings for electric device and construction fields.

• Korean Journal of Food Science and Technology
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• v.22 no.2
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• pp.145-149
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• 1990

Extraction and analysis conditions of di-(2-ethylhexyl) adipate (DOA) and its migration contents into foods wrapped with plasticized polyvinyl chloride (PVC) film during storage and cooking with microwave were examined using gas chromatography. Experiments on the extraction solvent and method showed that the method of reflux using carbon tetrachloride for longer than one hour allowed the highest extraction of DOA. Analysis of four PVC wrap films from different factories in domestic market showed the DOA contents of 18.9% for home-use and 24.6% for retail-use on the average. The highest migration during storage was observed in pork belly, which were 21% and 26% after one and three days respectively. During microwave cooking; smaller than 5.5% of DOA were migrated into foods when the film was not contacted with foods, whereas about 49% migration was observed in pork belly contacted with film directly.

• Nuclear Engineering and Technology
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• v.5 no.3
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• pp.223-233
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• 1973

Thirty two different kinds of domestic plastic films for use in measuring high gamma-ray dose have been collected and their dosimetric characteristics investigated with the help of a Co-60 gamma radiation source. Among them a rigid polyvinyl chloride(PVC) film of 0.06mm in thickness which is manufactured by Lucky Chemical Co., Korea, seem to be the most suitable one for this purpose. The relation between optical density at 3100$\AA$ and radiation exposure in this PVC film was linear in the range of 0.6$\times$10$^{6}$ R to 1.3$\times$10$^{7}$ R, and also the film showed a good reproducibility within 9% under the standard experimental condition. The effect of absorbed dose, oxygen content of surrounding atmosphere and irradiation temperature have also been studied for this film. It appeared to have a good property in the dosimetrical point of view.

• Smart Media Journal
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• v.12 no.5
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• pp.36-45
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• 2023

Recently, in digital agriculture, the types and utilization of greenhouses based on IoT are spreading, and greenhouses are being modernized, enlarged, and even factoryized using smart technology. However, a specific standardization plan has not been proposed according to the equipment for data collection in the smart greenhouse and the size or shape of the greenhouse. In other words, there is a lack of standard data for facility equipment, such as the type and number of sensors and equipment according to the size of the greenhouse, the type of greenhouse construction film and materials suitable for crops and carbon neutrality. Therefore, in this study, the suitability of the implementation, installation and quantity of IoT equipment for data collection was tested, and some standard technologies were presented through the implementation of data collection and communication methods. In addition, impact strength, tensile, tear, elongation, light transmittance, and lifespan issues for PE, PVC, and EVA, which account for about 90% of existing greenhouses, were presented, and the shape, size, and environmental problems of greenhouses made of films were presented. presented in the text. In this research paper, a standardized carbon-neutral modular smart greenhouse using nano-material film was implemented as a solution to environmental problems such as greenhouse size, farm crop type, greenhouse lifespan, and film, and its performance with existing greenhouses was analyzed and presented. Through this, we propose a modularized greenhouse that can be expanded or reduced freely without distinction in the size of the greenhouse or the shape of farmhouse crops, and the lifespan is extended and standardized. Finally, the average characteristics of greenhouses using existing PE, PVC, and EVA films and the characteristics of greenhouses using new carbon-neutral nanomaterials are compared and reviewed, and a plan to implement an expandable IoT greenhouse that supports carbon neutrality is proposed.