• Korean Journal of Bronchoesophagology
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• v.12 no.2
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• pp.19-25
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• 2006

There have been numerous modalities to recover blink function of orbicularis oculi muscle in patients with facial paralysis. However, there is still no optimal method for reanimation of eyelid. In this study, we tried to recover blink function of paralyzed rabbit's eyelid with the ion polymer metal composite (IPMC) which is one of the electroactive polymers that is spotlighted as artificial muscle. We manufactured IPMC by plating the platinum over perfluorosulphonic acid polymer ($Nafion^{(R)}$). IPMC was coated by Norland optical adhesive for the purpose of insulation and keeping it from dry. IPMC modifications by roughening the surface of Nafion, repetitive plating (maximum 4 times) with platinum, and lengthening the width of IPMC were done. The facial paralysis was induced in the rabbit by sectioning of facial nerve at the main trunk. After minimum period of 4 weeks, IPMC was inserted in the paralyzed rabbit's eyelid. By modification, the force generated by IPMC was enhanced. Restoration of blink function in paralyzed rabbit was achieved on electrical stimulation of the IPMC by 5 voltage direct current. IPMC can be promising option for facial reanimation, but further studies are needed to enhance the efficiency of IPMC.

• Environmental Engineering Research
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• v.18 no.4
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• pp.277-281
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• 2013

A dual-chamber microbial fuel cell (MFC) inoculated with Desulfovibrio desulfuricans and supplemented with lactate as an organic fuel was employed in this study. Biofilm formed on the anodic electrode was examined by scanning electron microscopy, revealing that the amount of biofilm was increased with repeated cycles of MFC operation. The maximum current production was notably increased from the first cycle ($1,310.0{\pm}22.3mA/m^2$) to the final cycle ($1,539.4{\pm}25.8mA/m^2$) of MFC run. Coulombic efficiency was also increased from $89.4%{\pm}0.2%$ to $98.9%{\pm}0.5%$. We suggest that the current production efficiency was related to the biomass of biofilm formed on the electrode, which was also increased as the MFC run was repeated. It was also found that D. desulfuricans, which colonized on the electrode, produced filaments or nano-pili. Nano-pili were effective for the attachment of cells on the electrode. In addition, the nano-pili provided a cell-to-cell link and stimulated the development of thicker electroactive biofilm, and therefore, they facilitated electron transfer to the anode. Conclusively, the biofilm of D. desulfuricans enhanced the current production in the MFC as a result of effective attachment of cells and electron transfer from the cell network to the electrode.

• Polymer Science and Technology
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• v.24 no.2
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• pp.177-182
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• 2013

• Environmental Engineering Research
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• v.19 no.1
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• pp.115-115
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• 2014

• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3415-3417
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• 2010

• International Journal of Control, Automation, and Systems
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• v.5 no.4
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• pp.429-435
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• 2007

A number of different alternative actuation methods have been under active development for some specific applications where the traditional electromechanical actuators are difficult to apply. Recently, many of these substitutes are trying to employ new smart materials like electroactive polymers. However most of the polymeric materials are flexible and vulnerable so that they normally can not sustain external forces. Although the materials have shown a good potential to be used for alternative actuation mechanisms, no tangible industrial application is yet presented because of the reason. A conceptual design for a rectilinear motion actuator using dielectric elastomer is presented in this article. The introduced design concept might enable to produce fairly controllable rectilinear motions for various applications and the presented prototype actuator system is fully packaged in a small unit and controlled by a standard communication interface.

• Journal of Biosystems Engineering
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• v.27 no.3
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• pp.249-258
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• 2002

The fourteen different electrodes coated with polymeric lipid membrane were evaluated to selectively monitor the sweet, salty, sour and bitter tastes, and umami. The polymeric lipid membrane consisted of the three components, or polymer matrix, plasticizer and electroactive material, the compositional ratio of which was 1:1.25:1. Herein, the 14 different electroactive materials were used. Sucrose, NaCl, citric acid, caffeine and MSG were used as standard materials of sweet, salty, sour and bitter tastes, and umami. The linear responses of each electrode regarding 5 tastes were analyzed by means of the correlation coefficient between electric potential difference and concentration of a taste material when the linearity was based on a linear model and a thermodynamic model, respectively. As fur salty taste, the electrode coated with valinomycin had a selective linearity at the significance level of 0.01. For monitoring sweet taste, the electrode with oleylamine and the electrode with the mixture of tai-n-octylmethylammonium chloride and dioctylphosphate (2:8) showed the significant linearities at the levels of 0.05 and 0.10, respectively.

• Journal of the Korean Vacuum Society
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• v.20 no.4
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• pp.276-279
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• 2011

Polymer electrostrictor materials can exhibit high electroactive strain and hold increasing promise for a variety of actuator applications. The size of available actuators has been limited, however, by the solution-based casting and annealing process generally required to prepare electrostrictor actuator materials. We report on a high throughput melt and stretch extrusion process capable of creating large sheets of an electrostructive terpolymer, poly (vinylidene fluoride-trifluoroethylene-1, 1-chlorofluoroethlene) while producing a suitable crystallinity and crystal phase for high strain electrostrictor performance such as artificial muscle systems.

• Smart Structures and Systems
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• v.15 no.6
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• pp.1601-1623
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• 2015

Electroactive polymers have attracted considerable attention in recent years due to their sensing and actuating properties which make them a material of choice for a wide range of applications including sensors, biomimetic robots, and biomedical micro devices. This paper presents an effective modeling strategy for nonlinear large deformation (small strains and moderate rotations) dynamic analysis of polymer actuators. Considering that the complicated electro-chemo-mechanical dynamics of these actuators is a drawback for their application in functional devices, establishing a mathematical model which can effectively predict the actuator's dynamic behavior can be of paramount importance. To effectively predict the actuator's dynamic behavior, a comprehensive mathematical model is proposed correlating the input voltage and the output bending displacement of polymer actuators. The proposed model, which is based on the rigid finite element (RFE) method, consists of two parts, namely electrical and mechanical models. The former is comprised of a ladder network of discrete resistive-capacitive components similar to the network used to model transmission lines, while the latter describes the actuator as a system of rigid links connected by spring-damping elements (sdes). Both electrical and mechanical components are validated through experimental results.

• Polymer(Korea)
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• v.29 no.4
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• pp.380-384
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• 2005

Fluoroalkyl methacrylate and acrylic acid were bulk radical copolymerized in the presence of pure sodium montmorillonite or macromer intercalated sodium montmorilonite to get a fluorinated acrylic ionomer/sodium montmorillonite composite, and their physical properties, such as X-ray diffraction pattern, tensile properties, and water uptake, were examined. These composites were used to preparean ionic acrylic polymer-platinum composite (IPMC). The current and deformation responses of these IPMCs by external voltage applied across the platinum electrodes deposited on both sides of IPMC showed that the cation migration from anode to cathode was suppressed in the presence of sodium montmorillonite, causing reduced current and deformation.