• Elastomers and Composites
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• v.42 no.3
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• pp.137-142
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• 2007

In the performance test of polytetrafluoroethylene (PTFE) membrane, melting temperature and crystallinity were $344.1^{\circ}C$ and 42.5%, respectively, according to TGA and DSC analysis. These values were similar to those of commercially available GE Osmonics PTFE membrane. The average of pore size was observed $0.716{\mu}m$ and the average flow rate was 1.570 LMH. These are slightly higher values than those of GE Osmonics sample. The filtering efficiency rate was 30.5%.

• Journal of Chest Surgery
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• v.39 no.3 s.260
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• pp.248-250
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• 2006

A 48-years-old woman was visited to our hospital because of incidental finding of intrapulmonary foreign body. Chest X-ray showed a 4cm sized foreign body in left upper lung field without adjacent fibrosis. Chest CT showed a sewing needle shaped foreign body of metallic density, located in the 113ft upper lobe. The foreign bodies including the needle were removed surgically using a wedge resection. The extracted needle was divided into three 4 cm pieces. Patient was discharged without other respiratory symptoms after surgery. We report a case of wedge resection in a patient with intrapulmonary needle in the left upper lobe, with review of literatures.

• Elastomers and Composites
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• v.30 no.3
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• pp.229-234
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• 1995

Membrane process has been applied widely to petroleum chemistry, fine chemistry, polymer, electronics, food, bioprocessing, and wastewater treatment process. Membrane process has advantage that there's no phase change through separation, energy consumption is smaller than other separation processes. And equipment investment and operation cost are inxpensive too. We prepared the silicone rubber membrane and then separated the heavy metal ion from wastewater. Silicone rubber membrane was prepared using a superitical fluid process and heavy metal ions were separated from the chromium nitrate, ferric sulfate, cupric sulfate, nickel sulfate aqueous solution. The pressure difference between top and bottom of separation apparatus was preserved by vacuum pump, and the removal amount of heavy metal at each separation step were analyzed by instrumental analysis, AAS. The surface and pore of silicone rubber membrane was investigated using SEM, and the capability of wastewater treatment using a silicone rubber membrane was proposed as calculated removal rate of heavy metal after comparing removal amount of heavy metal to amount of heavy metal in mother solution by AAS analysis.

• Applied Biological Chemistry
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• v.46 no.1
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• pp.46-49
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• 2003

Paddy and milled rice quality, milling characteristics, energy consumption of milling process were investigated using Dasanbyeo, Ansanbyeo, Hwaseongbyeo, Ilpumbyeo, and Donganbyeo varieties. Thousand grains weights of the varieties dried to 15% moisture content were 22.92-28.60 g, with Dasanbyeo being the heaviest. Optimum clearance of rubber roller for obtaining maximum dehulling recovery was 30% of each rice variety thickness. At that time, perfect brown rice ratios of Dasanbyeo, Ansanbyeo, Hwaseongbyeo, Ilpumbyeo, and Donganbyeo were 95.24%, 98.86%, 95.97%, 97.75%, and 97.31%, respectively, and showed no significant differences among varieties. Ratios of removed rice bran after two times milling ranged 70.93-91.38%, with Dasanbyeo showing the highest ratio, and the average head rice ratio was 92.87%.

• Membrane Journal
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• v.22 no.2
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• pp.142-154
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• 2012

In order to remove $CO_2$ from the DME plant process, we investigated the composite membrane with rubbery polymers as the separation layer and its separation performance of $CO_2$ and $H_2$. Hollow fiber membranes for supporting layer were prepared by solution spinning method. In case of using PDMS as a separation layer, the composite membranes showed the permeation rates of $CO_2$ were over 300 GPU and minimum $CO_2/H_2$ selectivitties were 4.3 and in case of using PEBAX as a separation layer, the composite membranes showed the permeation rates of $CO_2$ were over 120 GPU and minimum $CO_2/H_2$ selectivities were 5.

• Journal of Chest Surgery
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• v.38 no.3 s.248
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• pp.249-252
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• 2005

Neurogenic tumors of the brachial plexus region are relatively rare. We report a recent experience of schwannoma of the right brachial plexus in the inferior trunk, which was successfully treated by microsurgical resection. A 38-year- old man presented a dysesthetic pain in the supraclavicular area and the right forearm of C6, 7 dermatome. Rubbery hard mass was palpated in the right supraclavicular area and magnetic resonance imaging showed a well circumscribed, well enhanced ovoid mass with cystic degeneration on the right brachial plexus portion. The patient underwent complete removal of the mass through the anterior cervicothoracic (modified Dartevelle) approach. At the postoperative 3 months, there is no neurologic deficit.

• Journal of Soil and Groundwater Environment
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• v.8 no.2
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• pp.1-8
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• 2003

Two types of ground-water sampling techniques for CFCs (chlorofluorocarbons) analysis, the cold-welded copper tube method and flame-sealed borosilicate glass ampule method, were compared and evaluated. CFCs concentrations by the copper tube method showed a poor reproducibility among triplicates whereas those by the glass ampule method showed a good agreement and relative standard deviations of triplicates were less than 5%. The poor reproducibility of the copper tube method appears to be attributed to the incomplete sealing in connection between faucets of wellhead and the sampling apparatus. The copper tube method also showed higher CFCs concentrations than the glass ampule method, which is more pronounced for CFC-11 than for CFC-12. The plastic tubings and rubber gasket of faucets in case of the copper tube method possibly contaminated the samples with CFC-11 and CFC-12. The potential of CFCs contamination for the glass ampule method was eliminated by using stainless steel and Nylon only and by connecting the sampling equipment directly to the main discharge pipe of wellhead. The validity of the glass ampule method were also verified by detecting very low level of CFCs for the ground-water sample which is old enough to have negligible CFCs.

• Elastomers and Composites
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• v.45 no.2
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• pp.94-99
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• 2010

340 nm UV radiation of $2500\;kJ/m^2$ irradiated a thermoplastic elastomer (TPE) specimen used for interior and exterior materials of a car. After the UV irradiation, the black sample surface was changed to gray. Materials on the aged sample were collected and analyzed using GC/MS, but significant materials were not found. Lots of small cracks were found on the aged specimen surface. Whitening phenomenon of the aged sample disappeared by brushing or searing with a fire on the aged surface. After brushing or searing with a fire, small cracks on the surface vanished. Samples before and after the aging, and the treated samples with brush or fire were analyzed using image analyzer, SEM, EDX, and ATR and the results were compared. The vanished whitening phenomenon by brushing or searing was explained with filling the small cracks by polypropylene of TPE.

• Elastomers and Composites
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• v.44 no.4
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• pp.408-415
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• 2009

Iron-loaded activated carbon fibers (Fe-ACF) supported titanium dioxide ($TiO_2$) photocatalyst (Fe-ACF/$TiO_2$) was synthesized using a sol-gel method. Three different types of Fe-ACF/$TiO_2$ were obtained by treatment with different precursor of Fe, and characterized using BET, SEM, XRD and EDX analysis. The photocatalytic activity of Fe-ACF/$TiO_2$ was investigated by the degradation of Rhodamine B (Rh.B) solution under UV irradiation. From the experimental results, it was revealed that Fe-ACF/$TiO_2$ composites show considerable photocatalytic ability for the removal of Rh.B by comparing non-treated ACF/$TiO_2$ composites. And photo-Fenton reaction with Fe element was incoordinately influenced due to different precursor of Fe. It clearly indicates that Fe-ACF/$TiO_2$ composites prepared using $FeCl_3$ provided the highest photo-Fenton activity, then, which was affected by pH changes on the degradation of Rh.B.

• Elastomers and Composites
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• v.46 no.1
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• pp.10-21
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• 2011

Recently, with developments in the automotive industry, sound and vibration damping have a considerable attraction with a diversified customer needs and advanced automobile. In general, among various materials, textile materials, such as felt and glass fibers, polyurethane foam, and PET fiber materials were used to reduce sound and vibration of the automobile. These materials were located in various main parts of the automobile to block sound and vibration, resulting in a comfortable ride. In addition, to improve fuel economy, weight reduction and cost saving for the automobile were also being considered together as well as the reduction of sound and vibration of the automobile. Therefore, in this paper, we focused on the need of interior sound and vibration absorption materials in the automobile and absorption materials-related technologies.