• Korean Journal of Food Science and Technology
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• v.4 no.2
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• pp.95-99
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• 1972

Studies were made to investigate the influence of vacuum packing after irradiating mean doses of gamma ray at freezing temperature $(-20^{\circ}C)$ on the keeping quality and color of raw beef. Fresh round steaks were packaged anaerobically in aluminum foil, and irradiated with 0.25 and 0.5 Mrad followed by storage at $5^{\circ}C$. The shelf life of beef irradiated with 0.5 Mrad could be extended about 10 days longer than unirradiated, and the off-odors was not developed. The discoloration by irradiation was shown, but soon reverted to about 90 percentage myoglobin in 20 hours.

• Nuclear Engineering and Technology
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• v.40 no.1
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• pp.93-98
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• 2008

Several adhesive tapes have been studied in terms of their suitability for securing gold wires into positions for neutron flux measurements in the reactor core and irradiation facilities surrounding the core of the Open Pool Australian Light water (OPAL) reactor. Gamma ray spectrometry has been performed on each irradiated tape in order to identify and quantify activated components. Numerous metallic impurities have been identified in all tapes. Calculations relating to both the effective neutron shielding properties of the tapes and the error in measurement of the $^{198}Au$ activity caused by superfluous activity due to residual tape have been made. The most important identified effects were the prolonged cooling times required before safe enough levels of radioactivity to allow handling were reached, and extra activity caused by residual tape when measured with an ionisation chamber. Knowledge of the most suitable tape can allow a minimal contribution due to these effects, and the use of gamma spectrometry in preference to ionisation chamber measurements of the flux wires is shown to make all systematic errors due to the tape completely negligible.

• Applied Biological Chemistry
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• v.25 no.2
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• pp.105-109
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• 1982

The effect the physiochemical properties of red and white ginseng powder after $^{60}Co-{\gamma}$ ray irra diationduring the storage for 4 months at $25^{\circ}C$ was investigated. The storage periods and the treatment of irradation at various doses on ginseng powders has no significant effect on the proximate composition and color density of ginseng extract with 50% ethanol. No changes in the contents of saponin and its HPLC patterns were found during the storage. However, a little increase was found in the yield of 50% ethanol extract and Hunter's color value of powder. But generally it was found to be stable in the physicochemical properties of red and white ginseng powder by irradiation of the intensity during the storage.

• Journal of Radiation Protection and Research
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• v.22 no.3
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• pp.153-160
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• 1997

The frequencies of ${\gamma}$-ray-induced micronuclei (MN) in cytokinesis-blocked (CB) lymphocytes at several doses were measured in three donors of human and C57BL/6 mice. Measurements performed after irradiation showed a dose-related increases in MN frequency in each of the donors studied. The relative sensitivity of mouse in spleen lymphocytes (SLs) compared with human peripheral blood lymphocytes (PBLs) was estimated by best fitting linear-quadratic model based on the radiation-induced MN data over the range from 0 cGy to 400 cGy. In the case of MN frequency with 0.2 per CB cell, the relative sensitivity of mouse SLs was 1.67. Compared with the radiation-induced MN formation in the PBLs of human, the SLs of mouse were more radiosensitive. Using this MN assay with human PBLs and mouse SLs, studies were performed to determine whether the water fraction of ginseng (Panax ginseng C.A.Meyer) against radiation-induced MN in human PBLs after in vitro irradiation (3Gy) and in SLs of C57BL/6 mice after in vivo irradiation (3Gy). The frequency of MN in human PBLs was reduced by water fraction of ginseng (0.5mg/ml of medium) both pre-and post treatment (p<0.0l) in vitro. In addition, the frequency of MN in mouse SLs was also reduced by pretreatment of ginseng (2mg/ml of drinking water for 7days) in vivo. The data suggested that the ginseng may reduce cell damage caused by ${\gamma}$-rays in vitro and in vivo. Further studies are needed to characterize better the protective nature of ginseng extract, its fractions and compounds.

• Macromolecular Research
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• v.17 no.8
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• pp.580-584
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• 2009

The effects of crystallinity and radiation crosslinking on the physical properties of a microporous high density polyethylene (HDPE) film with Millad3988 as a nucleating agent were investigated. The pores of the HDPE film were affected by the crystallinity. The crystallinity of the HDPE films increased with increasing Millad3988 amount up to 0.1 wt% but decreased with further addition. The mechanical characteristics of the HDPE containing Millad3988 films improved with increasing irradiation dose up to 50 kGy, but decreased at 75 kGy due to severe degradation. The thermal shrinkage behavior of the HDPE films decreased with increasing radiation dose up to 50 kGy. The porosity of the stretched HDPEIMillad3988 films after ${\gamma}$-ray radiation increased with increasing y-ray radiation dose up to 50 kGy. The pores of the irradiated films were formed more easily by a stretching due to the formation of a crosslinked structure.

• Proceedings of the KIEE Conference
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• 1999.07d
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• pp.1992-1994
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• 1999

Dicumyl peroxide (DCP) is used for crosslinking agent in general. And the correlation between polyethylene and DCP is significant in particular radiation environment. On this paper, The effects on $Co^{60}{\gamma}$-ray irradiation of polyethylene doped dicumyl peroxide(DCP) were investigated. We experimented on electrical properties as following; electrical tree inception and growing type for applying AC step voltage, AC breakdown strength, volume resistivity, capacitance and dissipation factor at high frequency as increasing dosage. Also, chemical analysis was performed TGA, gel content.

• Macromolecular Research
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• v.17 no.10
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• pp.813-816
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• 2009

• Mycobiology
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• v.40 no.2
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• pp.145-146
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• 2012

The root of Hibiscus syriacus (Malvaceae) has been used for treatment of fungal diseases such as tinea pedis (athlete's foot). In this study, we investigated the antifungal constituent of the root of Hibiscus syriacus Ggoma, which was produced by a mutation breeding using gamma ray irradiation, and compared the antifungal activity of H. syriacus Ggoma and its parent type. According to the results, the methanolic extract of H. syriacus Ggoma exhibited four times higher antifungal activity than its parent type against Trichophyton mentagrophytes. Following purification through various column chromatographies, the antifungal substance was identified as nonanoic acid on the basis of spectroscopic analysis.

• Proceedings of the Plant Resources Society of Korea Conference
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• v.18 no.1
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• pp.123-123
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• 2005

• Korean Journal of Head & Neck Oncology
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• v.7 no.1
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• pp.3-9
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• 1991

Brachytherapy is a method of radiotherapy in advantage to achieve better local control with minimum radiation toxicity in comparison with external irradiation because radiation dose is distributed according to the inverse square low of gamma-ray emitted from the implanted sources. The main characteristics of brachytherapy are delivering of higher dose to target volume shortening of total treatment period and sparing of normal tissue. Recent development of iridium ribbons for low dose rate implant provides improvement of technology of brachytherapy in terms of safety and efficiency. High dose rate method. on the other hand, is effective to avoid unnecessary expoure of medical personnel.