• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.198-201
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• 2008

The electron beam irradiation was applied as a pretreatment of the enzymatic hydrolysis of yellow poplar with doses of 0$\sim$450 kGy. The higher irradiation dose resulted in the more degradation of hardwood biomass not only from carbohydrates but also from lignin. This changes originated from the irradiation resulted in the better response to enzymatic hydrolysis with commercial cellulases (Celluclast 1.5L and Novozym 342). The more improvement on enzymatic hydrolysis by the irradiation was found in the xylan than in the cellulose of yellow poplar.

• Journal of Radiation Industry
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• v.17 no.1
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• pp.75-82
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• 2023

This research was carried out to evaluate on microbiological (total aerobic bacteria, yeast and mold) and physicochemical (color, firmness, water content, water activity and weight loss) characteristics of 10MeV electron-beam irradiated(0, 0.5, 1, 2 and 3kGy) enoki mushroom during storage (0, 7, 14, 21 and 28 day) at 4℃ with 80% relative humidity. As compared to control, all irradiated samples exhibited dose-dependent decreases of microbial counts up to 28 days, and electron beam irradiation above 2 kGy kept below the microbiological safety threshold. Yellowness (b^*) which is associated with discoloration of mushrooms was significantly reduced by electron beam irradiation (2 kGy). Firmness, water content, water activity and weight loss showed no significant difference in all group up to 28 days. Thus, the appropriate electron-beam irradiation dose was confirmed as 2 kGy to inhibit the microbial growth and browning reaction in enoki mushroom.

• Electrical & Electronic Materials
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• v.10 no.8
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• pp.756-762
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• 1997

In this paper the change of electrical properties of transformer oil due to electron beam irradiation is investigated. The specimens are produced with a some different dose of 0.5[Mrad], 1[Mrad] and 2[Mard] except for original specimen. The physical properties of each specimen is analyzed by using the FT-IR spectrum. So it is confirmed that carbonyl groups are increased according to the increase of electron beam dose and also that the nitric compounds are disappeared. The magnitude of dielectric dissipation factor appears maximum value by the contribution of dipoles and ions in the low temperature low voltage region and it is stable due to the saturation of carriers in the high temperature high voltage region in the electric conduction characteristics. Volume resistivity is also measured one of original specimen is larger than irradiated specimen.

• Applied Science and Convergence Technology
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• v.23 no.5
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• pp.289-295
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• 2014

${\alpha}-V_2O_5$ nanorods were grown by means of electron beam irradiation and thermal oxidation methods and the visible emission properties of the nanorods grown by both methods were investigated. The growth and crystallinity of the nanorods were greatly enhanced by the insertion of a buffer layer. The emission spectra of the nanorods grown by thermal oxidation and electron beam irradiation showed a peak centered at 710~720 nm, which is believed to be due to oxygen vacancies introduced during the growth process. Also, the emission peak centered at 530 nm observed in the $V_2O_5$ nanorods grown by electron beam irradiation was considered to be due to the band edge transition as a result of the enhanced crystallinity.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.7
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• pp.1225-1232
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• 2000

This study was carried out to define the effect of electron beam irradiation on the physico-chemical characteristics of sewage sludges. The experimental evidence showed that both pH and alkalinity of irradiated sludge were generally increased as the dose of irradiation increased. It was found that the soluble protein concentration (SPC) and soluble chemical oxygen demand (SCOD) from the sludge right after electron beam irradiation at 3kGy(kilo-joule/kg) increased 2.2 times and 10 times respectively more than those sludges without electron beam treatment. This highly solubilized organics could be resulted in a good soluble substrate for the subsequent anaerobic digestion process. The specific resistance of filtration (SRF) tests showed that sludge dewaterability under electron beam irradiation at 6kGy was found to be 8.8 times higher than that of unirradiated sludge. The sludge dewaterability seemed to be directly related to the dosage of electron beam irradiation up to 10kGy. However, the efficiency of sludge dewaterability tended to be smaller with higher applied irradiation dose. In comparing treatments by different inorganic chemical conditioner with irradiated and unirradiated sludges, it appeared that the dewaterability with irradiated sludge was approximately 4-10 times better that that of unirradiated sludge. Even electron beam treatment itself could replace the result from the sludge conditioned with inorganic chemical coagulants.

• Journal of the Microelectronics and Packaging Society
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• v.30 no.3
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• pp.56-63
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• 2023

In this paper, we studied the effect of electron beam irradiation on sol-gel indium-gallium-zinc oxide (IGZO) thin films under air and nitrogen atmosphere and carried out the electrical characterization of the s ol-gel IGZO thin film transistors (TFTs). To investigate the optical properties, crystalline structure and chemical state of the sol-gel IGZO thin films after electron beam irradiation, UV-Visible spectroscopy, X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) were carried out. The sol-gel IGZO thin films exhibited over 80% transmittance in the visible range. The XRD analysis confirmed the amorphous nature of the sol-gel IGZO films regardless of electron beam irradiation. When electron beam irradiation was conducted in a nitrogen (N₂) atmosphere, we observed an increased proportion of peaks related to M-O bonding contributed to the improved quality of the thin films. Sol-gel IGZO TFTs subjected to electron beam exposure in a nitrogen atmosphere exhibited enhanced electrical characteristics in terms of on/off ratio and electron mobility. In addition, the electrical parameters of the transistor (on/off ratio, threshold voltage, electron mobility, subthreshold swing) remained relatively stable over time, indicating that the electron beam exposure process in a nitrogen atmosphere could enhance the reliability of IGZO-based thin-film transistors in the fabrication of sol-gel processed TFTs.

• Journal of Applied Biological Chemistry
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• v.57 no.2
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• pp.141-144
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• 2014

The effects of electron beam irradiation on control of Myzus persicae and Planocococcus citri (Risso) were evaluated with the changes of mortality, emergence rate, fecundity, and egg hatchability. As a result of this study, M. persicae and P. citri (Risso) was not directly affected by electron beam irradiation with low doses (30, 60, 90, and 120 Gy) but the irradiation had effects on inhibition of development and reproduction of the pests.

• Analytical Science and Technology
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• v.27 no.6
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• pp.292-299
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• 2014

Iopromide is an X-ray contrast agent that has been detected frequently with high concentration level in surface waters. Structural characterization of degradation products and measurement of degradation efficiency of iopromide by an electron beam irradiation were performed. For the fortified sample with iopromide, electron beam irradiation (UELV-10-10S, klysotrn, 10 MeV, 1 mA and 10 kW) was performed. The chemical structures of I_D_665 and I_D_663, which are degradation products of iopromide, were proposed by interpretation of mass spectra and chromatograms by LC/ESI-MS/MS. The mass fragmentation pathways of mass spectra in tandem mass spectrometry were also proposed. Iopromide was degraded 30.5~98.4% at dose of 0.3~5 kGy, and 97.8~30% in the concentration range $0.5{\sim}100{\mu}g/kg$ at electron beam dose of 0.3 kGy, respectively. Thus, increased degradation efficiency of iopromide by electron beam irradiation was observed with a higher dose of electron beam and lower concentration.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.1
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• pp.16-22
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• 2021

This study investigated the reduction in human norovirus (HNV) GII. 4 count in pacific oyster Crassostrea gigas using electron beam irradiation. Infectious HNV GII. 4 was detected using RT-qPCR (real time reverse transcription-quantitative polymerase chain reaction) with PMA (propidium monoazide)/sarkosyl. At electron beam doses 1, 5, 7, and 10 kGy, the count of HNV GII. 4 was 2.74, 2.37, 2.06, and 1.55 log copies/μL (control, 3.01 log copy/μL), respectively, confirming that as the irradiation dose increased, norovirus count reduced significantly (P<0.05). After PMA/sarkosyl treatment, the counts further reduced at the same irradiation dose, and 10 kGy showed significant differences between the non-treated and PMA/sarkosyl-treated samples (P<0.05). The Ed (decimal reduction dose of electron beam) value based on the first-order kinetic model was 7.33 kGy (R2=0.98). No significant difference was observed in the pH values of the control (6.2) and electron beam-irradiated samples at all doses (6.1). For sensory evaluation, the non-treated sample scored the highest in all categories (5.25-6.17), while the samples treated with 10 kGy showed the lowest score (4.67-5.33), although without statistical significance (P>0.05). Overall, our results suggest that 7 kGy electron beam is sufficient for the non-thermal sterilization of oysters without causing significant changes in quality.

• Journal of Radiation Industry
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• v.4 no.3
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• pp.259-263
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• 2010

Carbon fibers are used as a reinforcement material in an epoxy matrix in advanced composites due to their high mechanical strength, rigidity and low specific density. An important aspect of the mechanical properties of composites is associated to the adhesion between the surface of the carbon fiber and the epoxy matrix. This paper aimed to evaluate the effects of electron beam irradiation on the physicochemical properties of carbon fibers to obtain better adhesion properties in resultant composite. Chemical structure and surface elements of carbon fiber were determined by FT-IR, elemental analysis and X-ray photoelectron spectroscopy, which indicated that the oxygen content increased significantly with increasing the radiation dose. Thermal stability of the carbon fibers was studied via the thermalgravimetric analysis. Surface morphology of carbon fiber was analyzed by scanning electron microscope. It was found that the degree of surface roughness was increased by electron beam irradiation.