• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.26 no.3
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• pp.125-131
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• 2020

Carrageenan-based functional films were prepared by adding two different types of sulfur nanoparticles (SNP) synthesized from sodium thiosulfate (SNPSTS) and elemental sulfur (SNPES). The films were characterized using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction spectroscopy (XRD), and thermal gravimetric analysis (TGA). Also, film properties such as UV-visible light transmittance, water contact angle (WCA), water vapor permeability (WVP), mechanical properties, and antibacterial activity were evaluated. SNPs were uniformly dispersed in the carrageenan matrix to form flexible films. The addition of SNP significantly increased the film properties such as water vapor barrier and surface hydrophobicity but did not affect the mechanical properties. The carrageenan/SNP composite film showed some antibacterial activity against foodborne pathogenic bacteria, L. monocytogenes and E. coli.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.2
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• pp.113-118
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• 2011

This study was aimed to develop blend films by rice by-product (rice-hull and rice-bran) and bio-degradable materials. The rice by-product was firstly prepared from the pulverizing for making fine powder. Bio-degradable materials could be prepared by melting at high temperature. The mixture of the fine powder of rice by-product and melted bio-degradable materials was then blended and cast into films. The obtained films were investigated on their morphology, secondary structures and properties by using SEM, ICP and ASTM, respectively. Mechanical properties and degradability of these films were measured and compared to those of the PE films. Mechanical strength of bio-films was higher than that of PE films, however elongation ratio showed lower percent than that of PE film. In addition, bio-film could be degraded into fragments within 3 months under the field condition of normal upland crop cultivation. Bio-degradable mulching film indicated great potential for agronomic use as a new source of bio-degradable material.

• Journal of Electrochemical Science and Technology
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• v.10 no.3
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• pp.284-293
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• 2019

Herein, we report an electrode surface with a hierarchical assembly of wild-type M13 virus nanofibers (M13) to nucleate the AuPt alloy nanostructures by electrodeposition. M13 was pulled on the electrode surface to produce a virus film, and then a layer of sol-gel matrix (SSG) was wrapped over the surface to protect the film, thereby a bio-template was constructed. Blending of metal binding domains of M13 and amine groups of the SSG of the bio-template were effectively nucleate and directed the growth of nanostructures (NSs) such as Au, Pt and AuPt alloy onto the modified electrode surface by electrodeposition. An electrocatalytic activity of the modified electrode toward methanol oxidation in alkaline medium was investigated and found an enhanced mass activity ($534mA/mg_{Pt}$) relative to its controlled experiments. This bio-templated growth of NSs with precise composition could expedite the intention of new alloy materials with tuneable properties and will have efficacy in green energy, catalytic, and energy storage applications.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1998.10a
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• pp.99-102
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• 1998

우리나라 윈예생산 시설의 피복에 사용되는 피복자재는 값이 싸고 설치가 쉬우며 비교적 광투과율이 높고 시설에 피복할 경우 긴밀도가 뛰어나 보온력이 우수한 플라스틱 필름이 99 % 이상을 차지하고 있다. 최근에 플라스틱 필름의 종류는 다양하게 발전하여 소재는 PE(polyethylene), EVA(ethylene vinylacetate), PVC(polyvinylchloride), 등의 연질필름과 PET(poly ethylene terephthalate) 그리고 ETFE(ethylene tetrafluoride ethylene) 등의 반경질핌름으로 되어 있다. (중략)

• Journal of Bio-Environment Control
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• v.24 no.4
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• pp.326-332
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• 2015

The effect of biodegradable mulching film on the growth and development of garlic were investigated in order to develop eco-friendly weed control techniques. The treatments included biodegradable film (Bio-De) and black (Black-PE), green (Green-PE), transparent (Trans-PE) polyethylene mulching films. Non-mulched, bare soil (Non-mulching) was used as a control. Light transmittance value among tested mulching films was the highest in Trans-PE (86.1%) followed by Bio-DE and Green-PE, and the lowest value was observed for the Black-PE (1.1%). All mulching films without exclusion elevated soil temperature, especially Trans-PE and Bio-DE compared to bare soil. Plant height and mean bulb weight were increased due to mulching films with the highest values observed for Trans-PE and Bio-DE treatments. After seven months of field application there were no significant degradation signs on PE plastic films, whereas it was easy to see horizontal cracks on the Bio-DE film surface after five month of usage.

• Korean Journal of Medicinal Crop Science
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• v.26 no.4
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• pp.296-301
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• 2018

Background: The objective of this study was to investigate the effect of packaging material on the growth of rootstock of Liriope platyphylla. Methods and Results: This study examined the effects of two types of packaging material, LDPE (low density polyethylene) and functional film on the growth of the tubers of L. platyphylla, at $5^{\circ}C$. During the 16-weeks of storage period, the ratio of loss and decay of the tubers was examined at intervals of 4, 8, and 16 weeks to detect the quality of the plant. After 16 weeks of storage, the treated tubers were own. Subsequently, plant height and the number of leaves were recorded. The results revealed that functional film at $5^{\circ}C$ was the ideal material for the storage of L. platyphylla tubers. The rate of loss was the highest (57.42%) with a onion net and the lowest (22.12%) with a functional film. Similarly, the rate of tuber decay was highest (8.20%) using onion net and the least (4.60%) when the functional film was used. Conclusions: Thus, the use of the functional film proved to be the most effective in the storage of L. platyphylla tubers when compared with the LDPE.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2009.03a
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• pp.51-52
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• 2009

• Journal of Bio-Environment Control
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• v.4 no.2
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• pp.232-239
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• 1995

This study was carried out to get required torque data needed to design and develop a roll-up ventilation system in a pipe-constructed plastic film green-house. The results obtained from this study are as follows : 1. The required torques of a roll-up ventilation system in greenhouse are the functions of its length. The torques should multiplied by the conversion coefficients (2.0 in ceiling vent, 1.8 in side vent) in case of application. 2. In constructing pipe-constructed plastic film greenhouse, a shaft pipe is the largest essential element in roll - up shaft weight constitution which have an effect on the required torques. Therefore, the pipe should be light using nonferrous materials like aluminum alloy. 3. A planetary reduction ventilator of differential ring gear type is suitable for a roll-up ventilation system, because it can make high efficient reduction just using the first step shift.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.10.1-10.1
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• 2011

Energy harvesting technologies converting external sources (such as thermal energy, vibration and mechanical energy from the nature sources of wind, waves or animal movements) into electrical energy is recently a highly demanding issue in the materials science community for making sustainable green environments. In particular, fabrication of usable nanogenerator attract the attention of many researchers because it can scavenge even the biomechanical energy inside the human body (such as heart beat, blood flow, muscle stretching, or eye blinking) by converging harvesting technology with implantable bio-devices. Herein, we describe procedure suitable for generating and printing a lead-free microstructured $BaTiO_3$ thin film nanogenerator on plastic substrates to overcome limitations appeared in conventional flexible ferroelectric devices. Flexible $BaTiO_3$ thin film nanogenerator was fabricated and the piezoelectric properties and mechanically stability of ferroelectric devices were characterized. From the results, we demonstrate the highly efficient and stable performance of $BaTiO_3$ thin film nanogenerator and the integration of bio-eco-compatible ferroelectric materials may enable innovative opportunities for artificial skin and energy harvesting system.

• Textile Coloration and Finishing
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• v.22 no.3
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• pp.214-219
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• 2010

Polyethylene(PE) films were photocrosslinked by continuous UV irradiation. Benzophenone addition as low as 1wt% into the PE film increased the gel fraction up to 96%. The photocrosslinking was attributed to the recombination of PE radicals generated upon UV irradiation, which was enhanced by the hydrogen abstraction of the added benzophenone. Also the crossliked PE showed higher thermal stability and decreased crystallinity with increasing UV energy as shown by TGA, XRD and DSC analysis. It was also possible to fix 5.4% octadecane into PE by the photocrosslinking. The crosslinked PE film containing octadecane showed lower tensile strength and modulus coupled with higher extension compared to that without octadecane, which can be used as a new plasticizing method for the crosslinked PE film.