• Journal of Applied Biological Chemistry
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• v.51 no.3
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• pp.117-122
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• 2008

Inactivation of Agrobacterium tumefaciens was evaluated on the inoculated fresh Radix Ginseng by electron beam irradiation or aqueous chlorine dioxide ($ClO_2$) treatment. Two groups of fresh ginsengs were prepared and inoculated with A. tumefaciens. One group was then irradiated at 0, 2, and 4 kGy using an electron beam accelerator, and the other group was treated with 0, 50, and 100 ppm of aqueous $ClO_2$. Microbiological data indicated that populations of A. tumefaciens significantly decreased with increasing irradiation dose or aqueous $ClO_2$ concentration. In particular, A. tumefaciens was eliminated by irradiation at 4 kGy, and 100 ppm $ClO_2$ treatment reduced the populations of A. tumefaciens by 1.44 log CFU/g. These results suggest that electron beam irradiation or aqueous $ClO_2$ treatment can be useful in improving the microbial safety of fresh ginsengs during storage.

• Food Science and Preservation
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• v.10 no.2
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• pp.206-212
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• 2003

Comparative effects of electron beam and gamma-ray irradiation (25 ∼15 kGy) were investigated on saponin stability and some physiological and chemical properties of white and red ginseng powders. Saponin components were found stable upon irradiation of both energies when determined by TLC and HPLC, after 4 months of storage at room temperature as well as immediately after treatment The contents of total phenolics and acidic polysaccharides of the samples were higher in red ginseng than in white. Polysaccharide contents increased with irradiation doses. Amylase activity of white ginseng was stimulated by irradiation but decreased with the lapse of storage time. There were no apparent differences in electrophoresis patterns of extracted proteins depending on irradiation doses and energy sources.

• Nuclear Engineering and Technology
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• v.52 no.2
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• pp.373-380
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• 2020

This study was carried out to convert the hydrophobic characteristics of PVDF to hydrophilic. Poly(-vinylidene fluorine) (PVDF) was grafted by electron beam irradiation and sulfonated. The grafting degree of modified PVDF increased with the monomer concentration, but not the conversion degree. From the results of FTIR and XPS, it was shown that the amount of converted sulfur increased with the grafting degree. The radiation-induced graft polymerization led to decrease fluorine from 35.7% to 21.3%. Meanwhile, the oxygen and sulfur content increased up to 8.1% and 3.2%. The pore size of modified membranes was shrunken and the roughness sharply decreased after irradiation. The ion exchange capacity and contact angle were investigated to show the characteristics of PVDF. The enhanced ion exchange capacity and lower contact angle of modified PVDF showed that the hydrophilicity played a role in determining membrane fouling. Electron beam irradiation successfully modified the hydrophobic characteristics of PVDF to hydrophilic.

• Textile Coloration and Finishing
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• v.21 no.1
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• pp.46-52
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• 2009

Dyeing properties of hydrophobic polypropylene fibers using cationic dyes were investigated to improve dyeability by electron beam irradiation and sulfonic acid incorporation. The color strength of irradiated polypropylene fibers was examined according to the dyeing conditions including pH of dyebath, absorbed doses, and introduction of functional group to fiber substrate. The best dyeing result was obtained when sulfonic acid group incorporated polypropylene fibers after electron beam irradiation were dyed with cationic dyes at alkaline conditions and 30$\sim$75kGy irradiation ranges.

• Journal of Radiation Industry
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• v.5 no.4
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• pp.297-303
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• 2011

The purpose of this research is to detect whether agricultural products were electron beam irradiated or non-irradiated by chemical methods according to increase of storage period. The three fat-rich samples including soybean, walnut, and sesame were chosen as agricultural products, and then were irradiated with doses of 1~10 kGy by using 10 MeV electron beam facility. At the result, 8-heptadecene and 1,7-hexadecadiene, which are indicators of electron beam-irradiation in chemical methods by gas chromatography/mass spectrometry(GC/MS) method, were detected in all three samples. The levels of two irradiation indicators were increased by electron beam-irradiation in a dose-dependent manner. Furthermore, two irradiation indicators also were detected in all samples in 6 and 12 months after irradiation, though levels of those were decreased in a time-dependent manner. These results mean that the quantification of 8-heptadecene and 1,7-hexadecadiene could determine whether electron beam were irradiated or non-irradiated until 12 month after irradiation in 3 fat-rich agricultural products including soybean, walnut, and sesame.

• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.179-182
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• 2006

The effect of electron beam irradiation on dye sensitized solar cell (DSSC) has been studied to examine degradation of DSSC. The high-energy electron beam irradiation affects on the materials and performance of dye sensitized solar cells. We have checked the effects of electron beam irradiation of $TiO_2$ substrate with and without dye adsorption on the photovoltaic performances of resulting DSSCS and also studied the structural and electrical properties of polymers after irradiation. All solar cells materials were irradiated by electron beams with an energy source of 2MeV at different dose rates of 60 kGy, 120 kGy 240 kGy and 900 kGy and then their photoelectrical parameters were measured at 1 sun $(100 mW/cm^2)$. It was shown that the efficiency of DSSC was decreased as increasing the dose of e-beam irradiation due to lowering in $TiO_2$ crystallinity, decomposition of dye and oxidation of FTO glasses. On the other hand, the performance of solid-state DSSC with polyethylene oxide based electrolyte was improved after irradiation of e-beam due to enhancement of its conductivity and breakage of crosslinking.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.3
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• pp.248-255
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• 2010

This study was carried out to assess the feasibility of the electron beam irradiation as a mean of red tide control in coastal water. Prorocentrum minimum, Prorocentrum micans, Cochlodinium polykrikoides, Heterosigma akashiwo, Alexnadrium catenella were selected and cultured for experiments, and red tide occurring in Tongyeong(2007. 8. 15) was also tested under the same conditions. The irradiation dose were 1 kGy, 2 kGy, 4 kGy and 8 kGy. The result showed 50~65% extinction in red tide cells was observed right after irradiation dose of 1 kGy and 86~97% within 1 day after irradiation, compared with control. Chlorophyll-a concentration of red tide was reduced by 50~64% immediately and it was drastically reduced up to 86~97% 1 day after irradiation. When the culture was irradiated at 1 kGy, 28~47% of s-protein was released immediately, and 77~138% was released 1day after irradiation. 77~212% of s-carbohydrate was excreted after 1 day while 16~45% of s-carbohydrate was excreted immediately. A transmission electron microscope(TEM) observation for the irradiated red tide revealed that the cell was destroyed and intracellular biopolymeric substance was leached out from the damaged cell as a result of electron beam irradiation. These results imply that electron beam irradiation is enable to control red tide by flocculation with extracellular biopolymer. The paralytic shellfish poisoning(PSP) toxin contents produced by Alexandrium catenella was decreased 48% by 1 kGy of electron beam irradiation compared with the unirradiated cells. As a result, electron beam irradiation was effective for detoxication as well as destruction of red tide.

• Journal of Radiation Protection and Research
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• v.42 no.1
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• pp.63-68
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• 2017

Background: The combined effect of the low energy electron (LEE) irradiation and $Cu^{2+}$ ion on DNA damage was investigated. Materials and Methods: Lyophilized pBR322 plasmid DNA films with various concentrations (1-15 mM) of $Cu^{2+}$ ion were independently irradiated by monochromatic LEEs with 5 eV. The types of DNA damage, single strand break (SSB) and double strand break (DSB), were separated and quantified by gel electrophoresis. Results and Discussion: Without electron irradiation, DNA damage was slightly increased with increasing Cu ion concentration via Fenton reaction. LEE-induced DNA damage, with no Cu ion, was only 6.6% via dissociative electron attachment (DEA) process. However, DNA damage was significantly increased through the combined effect of LEE-irradiation and Cu ion, except around 9 mM Cu ion. The possible pathways of DNA damage for each of these different cases were suggested. Conclusion: The combined effect of LEE-irradiation and Cu ion is likely to cause increasing dissociation after elevated transient negative ion state, resulting in the enhanced DNA damage. For the decrease of DNA damage at around 9-mM Cu ion, it is assumed to be related to the structural stabilization due to DNA inter- and intra-crosslinks via Cu ion.

• Journal of the Korean institute of surface engineering
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• v.53 no.6
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• pp.280-284
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• 2020

Electron beam irradiation is widely used as a type of surface modification technology to advance surface properties. In this study, the effect of electron beam irradiation on properties, such as surface hardness, wear resistance, roughness, and critical load of Titanium Aluminium nitride (TiAlN) films was investigated. TiAlN films were deposited on the SKD-61 substrate by using cathode arc ion plating. After deposition, the films were bombarded with intense electron beam for 10 minutes. The surface hardness was increased up to 4520 HV at electron irradiation energy of 1500 eV. In addition, surface root mean square (RMS) roughness of the films irradiated at 1500 eV shows the lowest roughness of 484 nm in this study.

• Journal of Radiation Industry
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• v.7 no.1
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• pp.51-54
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• 2013

Chitosan is a useful natural polymer material in many application fields such as biomaterials, water-treatment, agriculture, medication, and food science. However, the poor solubility limits its application. In this study, the effects of radiation on chitosan were investigated using gamma ray and electron beam irradiation. The chemical structure and molecular weight analysis show similar degradation effects of chitosan powder in both gamma ray and electron beam irradiation. However, the radiation irradiated chitosan in $H_2O$ has a lower molecular weight, since the hydroxyl radicals attack the glycosidic bonds. This effect is more clearly shown in the electron beam irradiation results.