• KIEE International Transactions on Electrophysics and Applications
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• v.5C no.1
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• pp.23-27
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• 2005

We observed that optical properties of silicon changed under high dose electron irradiation at 250 keV. Our experimental results revealed that the optical transmission through a silicon wafer is significantly increased by electron irradiation. Transmission increase by the change in the absorption coefficient is explained through an analogy with amorphous silicon. Moreover, solar cell open-circuit voltages indicated that defects were generated by electron irradiation, and that the defects responded to annealing. Our results demonstrated that the optical properties of silicon can be controlled by a combination of electron irradiation and hydrogen annealing.

• Transactions on Electrical and Electronic Materials
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• v.14 no.4
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• pp.208-210
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• 2013

ZnO films were deposited on glass substrates by radio frequency (RF) magnetron sputtering and exposed to intense electron beam irradiation to investigate the effects of electron irradiation on the properties of the films. Although all of the films had ZnO (002) textured structure regardless of electron irradiation, the grain sizes of the films decreased with electron irradiation. Surface roughness also depended on electron irradiation. The surface roughness varied between 2.3 and 1.6 nm, depending on the irradiation energy. Based on photoluminescence (PL) characterization, the most intense UV emission was observed from ZnO films irradiated at 900 eV. Since the intensity of UV emission is dependent upon the stoichiometric of ZnO films, we conclude that 900 eV was the optimum electron irradiation energy to achieve the best stoichiometric of ZnO films in this study.

• Journal of the Korean Society for Heat Treatment
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• v.27 no.5
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• pp.225-229
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• 2014

The influence of electron irradiation energy(eV) on the structural, electrical and optical properties of ITO/ZnO bi-layered films prepared with RF magnetron sputtering has been investigated. The ITO/ZnO show the lowest resistivity of $2.8{\times}10^{-4}{\Omega}cm$. The optical transmittance in a visible wave length region also increased with the electron irradiation energy. The film irradiated at 900 eV shows 82---- of optical transmittance in this study. By comparison of figure of merit, it was observed the optical transmittance and electrical resistivity of the films were dependent on the electron irradiation energy and optoelectrical performance of ITO/ZnO film is improved with electron irradiation.

• Journal of People, Plants, and Environment
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• v.23 no.2
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• pp.171-178
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• 2020

The present study was conducted to determine the effects of electron beam irradiation on the postharvest quality of cut flowers. Cut flowers were irradiated with electron beam at 100, 200, 400, 600, 800, 1,000, and 2,000 Gy with a 10 MeV linear electron beam accelerator to evaluate their irradiation tolerance. Postharvest quality was determined by monitoring fresh weight loss, flower longevity, flower diameter, flowering rate, visual quality of flowers and leaves, and chlorophyll content. Cut flowers showed a radiation-induced damage with increasing the irradiation dose. Flower longevity and fresh weight of cut flowers decreased when the irradiation dose was increased. Flower bud opening was also inhibited in a dose-dependent manner. The effective irradiation doses for 10% reduction of postharvest quality (ED₁₀) values were 144.4, 451.6, and 841.2 Gy in the 'Medusa' lily, 'Montezuma' carnation, and 'Rosina White' eustoma, respectively. Although tolerance of cut flowers to electron beam irradiation vary according to species, cultivars, or maturity stage conditions, it is conceivable that 'Montezuma' carnation and 'Rosina White' eustoma could be tolerated and maintained overall postharvest quality up to 400 Gy, the generic irradiation dose approved by the Animal and Plant Health Inspection Service (APHIS) and the International Plant Protection Convention (IPPC) for postharvest phytosanitary treatments.

• Food Science of Animal Resources
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• v.30 no.4
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• pp.603-608
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• 2010

This study investigated the effects of electron beam irradiation on pathogens, quality, and functional properties of shell eggs during storage. A 1st grade 1-d-old egg was subjected to electron beam irradiation at 0, 1, 2, and 3 kGy, after which the number of total aerobic bacteria, reduction of inoculated Escherichia coli and Salmonella Typhimurium, egg quality, and functional properties were measured. Electron beam irradiation at 2 kGy reduced the number of E. coli and S. Typhimurium cells to a level below the detection limit (<$10^2$ CFU/g) after 7 and 14 d of storage. Egg freshness as measured by albumen height and the number of Haugh units was significantly reduced by 1-kGy irradiation. The viscosity of irradiated egg white was also significantly decreased by increased irradiation, whereas its foaming ability was increased. Electron beam irradiation also increased lipid oxidation in egg yolks. These results suggest that electron beam irradiation reduces the freshness of shell eggs while increasing the oxidation of egg yolk and improving important functional properties such as foaming capacity. Electron beam irradiation can also be applied to the egg breaking process since the irradiation reduces the viscosity of egg white, which can allow egg whites and yolks to be separated with greater efficiency.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.5
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• pp.68-73
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• 2015

Electron beam irradiation is also an eco-friendly treatment compared to other physical and chemical treatments. In this study, we attempted to evaluate the possibilities of energy savings by applying electron beam irradiation to the refining process. After softwood unbleached kraft pulp (UKP) was irradiated with electron beams at 50 and 100 kGy, it was beaten in a laboratory beater, and then its freeness and fiber properties were analyzed. The physical properties of their fiber handsheet were also and measured. As the irradiation dose of the electron beam and the beating time increased, lower freeness and fiber lengths of the UKP were observed. Handsheets made from UKP that was irradiated by electron beam and beaten showed a reciprocal relationship with the irradiation dose of the electron beam, in particular, the strength of the handsheets decreased dramatically at 100 kGy of irradiation. Therefore, it was confirmed that electron beam irradiation is effective in reducing the beating time or beating energy. But the irradiation dose must be controlled under 50 kGy to minimize the loss of paper strength.

• Preventive Nutrition and Food Science
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• v.14 no.4
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• pp.362-366
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• 2009

To determine the effect of electron-beam irradiation on the contents of polymethoxylated flavones (PMFs) extracts from citrus pomaces (CP), CP was irradiated at 0, 1, 2, or 5 kGy. Methanol extract of the irradiated CP were prepared and the PMF (nobiletin, sinensetin, and tangeretin) content of the extract was determined. Nobiletin and sinensetin of CP extract significantly increased with irradiation dose-dependent. However, electron-beam irradiation decreased the amount of tangeretin in the CP extract. These data suggest that irradiation can liberate phenolic compounds such as nobiletin or sinensetin, but tangeretin might have different pathway of conversion by irradiation. Therefore, irradiation can be a tool to change the composition of PMFs in CP.

• Journal of Radiation Industry
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• v.6 no.1
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• pp.55-59
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• 2012

Polyacrylonitrile (PAN)-based carbon fibers have been widely used due to their unique chemical, electrical, and mechanical properties. Electron beam irradiation has been extensively employed as means of altering properties of polymeric materials. Electron beam irradiation can induce chemical reactions in materials without any catalyst. Electron beam irradiation may be useful in accelerating the thermal compression stabilization of PAN nanofibers. To investigate the irradiation effect on PAN fibers, PAN nanofibers were irradiated by electron beam at 1,000~5,000 kGy. Irradiated and non-irradiated PAN nanofibers were heated at 180 and $220^{\circ}C$ without applying pressure for 15 min. Then 1 metric ton has been applied for 5 min. SEM images have been found that the fiber kept its morphological behavior after the hot pressing up to electron beam irradiated 1,000 kGy. DSC thermograms showed that the peak temperatures of the exothermic reactions were found to decrease with increasing electron beam irradiation doses and temperature. FT-IR spectra have been found to decrease $C{\equiv}N$ stretch band with increasing the electron beam irradiation dose. These results indicate that the modification of PAN via reactions such as cyclization is significantly enhanced by electron beam irradiation and thermal compression technique.

• Preventive Nutrition and Food Science
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• v.11 no.4
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• pp.344-347
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• 2006

This study evaluated the use of electron beam irradiation for decontamination of the Korean medicinal herb, Angelica gigas Nakai. Herb samples were irradiated at doses of 2, 8, and 16 kGy, respectively. Populations of microorganisms in Angelica gigas Nakai decreased by 2$\sim$3 log cycles at 8 kGy irradiation. Electron beam irradiation caused negligible changes in Hunter color L, a, and b values. Sensory evaluations of Angelica gigas Nakai confirmed that irradiation caused no significant changes in the organoleptic properties of the samples. These results suggest that electron beam-irradiated herbs retain a better microbial safety and sensory qualities, compared with the non-irradiated.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.39 no.5
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• pp.20-25
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• 2007

Henequen fibers were treated by electron beam irradiation and by NaOH to make surface modification for better bonding in the manufacture of biocomposite. Impurity removal and carbonyl group formation were noticed in the previous study by electron beam irradiation, but extensive cellulose degradation were also noticed. To evaluate the effects of electron beam irradiation on cellulosic fibers further, henequen fibers, cotton pulp, cotton fibers, and cellophane were irradiated by electron beam, and their changes of cellulose viscosity, chemical composition, and tensile strength were measured and analyzed.