• Transactions on Electrical and Electronic Materials
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• v.15 no.5
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• pp.257-261
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• 2014

Multilayered CdTe/PSS films were prepared by the electrostatic self-assembly method in an aqueous medium. Positively-charged cadmium telluride (CdTe) nanoparticles and anionic polyelectrolyte, poly (sodium 4-styrene sulfonate) (PSS) were assembled alternately in order to build up a multilayered film structure. A linear proportion of absorbance to the number of bilayers suggests that an equal amount of CdTe was adsorbed after each dipping cycle, which resulted in the buildup of a homogenous film. The binding energies of elements (Cd and Te) in multilayered CdTe/PSS film shifted from those of the CdTe nanoparticles in the pure state. This result indicates that the interfacial electron densities were redistributed by the strong electrostatic interaction between the oppositely-charged CdTe and PSS. Electrochemical properties of the multilayered CdTe/PSS films were studied in detail by cyclic voltammetry (CV).

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.43 no.2
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• pp.49-56
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• 2011

Mulching technique is used to control the temperature and moisture content of soil by covering the ground surface. Most kinds of mulching film are made of polyethylene which is non-biodegradable synthetic polymer. Utilizing these films has been one of the main sources in soil pollution. Thus residual films under the ground should be removed after a certain period of time. Therefore, an alternative mulching material made of biodegradable functional paper is considered instead of non-biodegradable films. The mulching sheet produced from paper basis has a functionality to be naturally degraded and then recycled to the bio-materials on soil. In this study, the paper based-mulching sheet coated with biodegradable polymer was specially produced using a laboratory bar coater. Coating colors prepared by dissolving PBS/PLA in chloroform were applied to kraft paper. The mechanical strength and aging properties of this mulching sheet were investigated. The burst strength of polymer-coated paper was decreased with the increase of the PBS ratio in PBS/PLA blends, and, in particular, 30/70 blending condition led to good stability in heat-aging atmosphere for 60 days.

• Bulletin of the Korean Chemical Society
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• v.32 no.3
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• pp.927-933
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• 2011

Conducting polyaniline-poly($\varepsilon$-caprolactone) polymer composites were synthesized via in situ deposition techniques. By dissolving different weight percentages of poly($\varepsilon$-caprolactone) (PCL) (10%, 20%, 30%, 40%, and 50%), the oxidative polymerization of aniline was achieved using ammonium persulfate as an oxidant. FTIR, UV-vis spectra, and X-ray diffraction studies support a strong interaction between polyaniline (PANI) and PCL. Structural morphology of the PANI-PCL polymer composites was studied using scanned electron microscopy (SEM) and transmittance electron microscopy (TEM), and thermal stability was analyzed by thermogravimetric analysis (TGA) technique. The temperature-dependent DC conductivity of PANI-PCL polymer composite films was studied in the range of 305-475 K, which revealed a semiconducting behavior in the transport properties of the polymer films. Conductivity increased with the increase of PCL in below critical level, however conductivity of the polymer film was decreased with increase of PCL concentration higher than the critical value.

• Korean Chemical Engineering Research
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• v.61 no.4
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• pp.584-590
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• 2023

In this study, we focus on the recycling of cardboard waste and sugarcane bagasse (SCB) for the preparation of carboxymethyl cellulose (CMC) and its conversion into a biodegradable film. Sodium alginate (SA) was added to form a biodegradable composite film. SA was used to increase film permeability. Glycerol, which is a plasticizer, was used to increase the tensile strength (TS) and film expansion. To characterize the CMC, X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy were used. The addition of olive oil to the CMC-SA matrix highlighted its antimicrobial property against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). A slight decrease in tensile strength was observed with the addition of olive oil (OO), which improved the functional properties of the control films as well as lowered moisture content and water solubility. But considering all other factors, the composite films obtained from sugarcane bagasse and cardboard waste incorporated with olive oil are suitable for applications in the field of food packaging.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.231.1-231.1
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• 2015

Surface energy, being an important material parameter to control its interactions with the other surfaces plays a key role in bio-related application. Carbon films are found very promising due to their characteristics such as wear and corrosion resistant, high hardness, inert, low resistivity and biocompatibility. The present work deals with the deposition of carbon films using unbalanced facing target magnetron sputtering technique. The discharge characteristics were studied using optical emission spectroscopy and correlated with the film properties. Surface energy was investigated through contact angle measurement. The ID/IG ratio as calculated from Raman spectroscopy data increases with the increase in power density due to the higher number of sp2 clusters embedded in the amorphous matrix. The deposited films were smooth and homogeneous as observed by Atomic force microscopy having RMS roughness in the range of 1.74 to 2.25 nm. It is observed that electrical resistivity and surface energy varies in direct proportionality with operating pressure and has inverse relation with power density. The surface energy results clearly exhibited that these films can have promising applications in cell cultivation.

• Proceedings of the Korean Ceranic Society Conference
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• 2002.10a
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• pp.12-12
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• 2002

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.12 no.2
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• pp.117-123
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• 2006

To mass-product useful biopolymer films, chitosan/gelatin blend films were prepared by solution casting method. Effect of mixing ratio, tensile strength(TS), elongation(${\Delta}E$) at break, total color difference(E), water vapor permeability(WVP) and oxygen permeability(OP) on chitosan/gelatin blend films properties were investigated. TS, ${\Delta}E$, E, WVP and OP values of chitosan/gelatin blend films were 43.43-38.30 MPa, 9.02-15.09%, 1.28-3.81, $0.8420-0.9673ng{\cdot}m/m^2{\cdot}s{\cdot}Pa$ and $1.5472{\times}10^{-7}-1.5424{\times}10^{-7}mL{\cdot}{\mu}m/m^2{\cdot}s{\cdot}Pa$, respectively. TS of the blend films decreased, while E and E of the blend films increased with increasing chitosan content. WVP and OP of the blend films did not show any significant relationship with mixing ratio and thickness of the blend films. OP of the blend films were lower than those of low density polyethylene and oriented polypropylene.

• Journal of radiological science and technology
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• v.37 no.3
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• pp.169-175
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• 2014

According to database of medical institutions of health insurance review & assessment service in 2013, 1118 hospitals and clinics have department of radiology in Korea. And there are CT, fluoroscopic and general radiographic equipment in those hospitals. Above all, general radiographic equipment is the most commonly used in the radiology department. And most of the general radiographic equipment are changing the digital radiography system from the film-screen types of the radiography system nowadays. However, most of the digital radiography department are used the film-screen types of the radiography system. Therefore, in this study, we confirmed present conditions of technical items for general radiography used in hospital and research on general radiographic techniques in domestic medical institutions. We analyzed 26 radiography projection method including chest, skull, spine and pelvis which are generally used in the radiography department.

• Journal of Bio-Environment Control
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• v.18 no.1
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• pp.9-14
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• 2009

This experiment was conducted to investigate the difference among 3-years-used Polyolefin films which were J-1, J-2 and J-3 having differences in film thickness, infrared absorption and ultraviolet penetration from Jan. 16,2006. And 1-year-used Polyethylene film K-1 used from Jan. 16,2008, for covering film of greenhouse for korea melon cultivation. J-2, J-3 and J-1 films were better for keeping heat in order, and J-2 film was the best in plant growth at early stage. The first blooming and harvesting days in J-2 film were earlier 10 days than those in K-1 film. Chromaticity and soluble solid of harvested fruit in J-3, J-1 and J-2 films were higher than those in K-1 film. Marketable yields in J-2, J-1 and J-3 films were higher in order.

• Journal of Bio-Environment Control
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• v.19 no.3
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• pp.135-139
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• 2010

This experiment was conducted to investigate the difference among 3-years-used polyolefin films which were J-l, J-2 and J-2 having differences in film thickness, infrared absorption and ultraviolet penetration from Jan. 16, 2006. And 1-year-used polyethylene film K-1 used from Jan. 16, 2009, for covering film of greenhouse for oriental melon cultivation. J-2, J-3 and J-1 films were better for keeping heat in order, and J-2 film was the best in plant growth at early stage. The first blooming and harvesting days in J-2 film were earlier 15 days than those in K-1 film. Chromaticity and soluble solid of harvested fruit in J-2, J-3 and J-1 films were higher than whose in K-1 film. Marketable yields in J-2, J-3 and J-1 films were higher in order.