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Carbon Nanocomposite Based Mechanical Sensing and Energy Harvesting
Changyoon Jeong,Chanwoo Joung,Seonghwan Lee,Maria Q. Feng,Young-Bin Park 한국정밀공학회 2020 International Journal of Precision Engineering and Vol.7 No.1
Progresses in sensor and energy technologies have been an important driving force for the rapid development of these industries and have drawn the attention of researchers on environmental concerns. In particular, carbon nanomaterial (carbon nanotubes, graphene, graphite, etc.)-based composites are widely used for sensor and energy harvesting applications owing to their excellent electrical, thermal, and mechanical properties. In this review, we have discussed various aspects of the use of carbon nanocomposites for the development of sensor and energy harvesting devices. These devices have shown outstanding sensing and energy harvesting performances. Various carbon nanomaterial-based composites with sophisticated structural and material designs have been developed to improve their sensing performance for various applications. We have also reviewed recent technological developments in carbon nanocomposite-based energy generators that adopt thermoelectric and triboelectric working mechanisms. Further research on the development of carbon nanocomposites with enhanced sensing and energy harvesting properties will expand the range of their applications to automotive, aerospace, artificial skin, healthcare, and environmental/infrastructure industries.
Byeong-Joo Kim,Biplab K. Deka,Chanwoo Joung,박영빈 한국정밀공학회 2021 International Journal of Precision Engineering and Vol.8 No.2
Polypropylene (PP) nanocomposite films reinforced with surface-modified nanoclay, maleic anhydride-grafted PP (PP-g-MA), and surfactants, such as cetyl-trimethyl-ammonium bromide (CTAB) and octadecyl-trimethyl-ammonium bromide (ODAB), were fabricated by extrusion, and the effect of surfactant type used for the nanoclay and the take-up speed of extrusion on the mechanical properties and crystallinity of the nanocomposite films were investigated. Multi-scale hybrid composites (MHCs) consisting of plasma-treated plain woven carbon fiber (WCF) and nanocomposite films were manufactured by hot pressing. Flexural and impact tests were performed to measure the mechanical properties at various plasma treatment times. Scanning electron microscopy and X-ray photoelectron spectroscopy (XPS) were used to observe the surface morphology and detect polar functional groups, respectively. Results of XPS analysis showed a considerable increase in the oxygen atomic percentage after plasma treatment. The mechanical properties of the MHCs were greatly affected by the presence of nanoclay in the composite and the plasma treatment. The flexural modulus and strength, impact force, and absorbed impact energy of the MHC specimens treated with plasma (15 s) and reinforced with nanoclay/ODAB(5:1, 1.5 wt%) and PP-g-MA(3 wt%), increased by 69, 87, 49 and 54%, respectively, compared to the neat non-plasma-treated WCF/PP composites.
Kwangdon Kim,Hakjae Lee,Jinwook Jang,Yonghyun Chung,Donghoon Lee,Chanwoo Park,Jinhun Joung,Yongkwon Kim,Kisung Lee 대한전자공학회 2017 IEIE Transactions on Smart Processing & Computing Vol.6 No.1
Radioactive materials are used in medicine, non-destructive testing, and nuclear plants. Source localization is especially important during nuclear decommissioning and decontamination because the actual location of the radioactive source within nuclear waste is often unknown. The coded-aperture imaging technique started with space exploration and moved into X-ray and gamma ray imaging, which have imaging process characteristics similar to each other. In this study, we simulated 21x21 and 37x37 coded aperture collimators based on a modified uniformly redundant array (MURA) pattern to make a gamma imaging system that can localize a gamma-ray source. We designed a 21x21 coded aperture collimator that matches our gamma imaging detector and did feasibility experiments with the coded aperture imaging system. We evaluated the performance of each collimator, from 2 mm to 10 mm thicknesses (at 2 mm intervals) using root mean square error (RMSE) and sensitivity in a simulation. . In experimental results, the full width half maximum (FWHM) of the point source was 5.09° at the center and 4.82° at the location of the source was 9°. We will continue to improve the decoding algorithm and optimize the collimator for high-energy gamma rays emitted from a nuclear power plant.