• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.5
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• pp.777-781
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• 2001

The effects of gamma-irradiation on the nutritional components of some Korean soybean-based fermentation foods were studied. Doenjang (soybean paste), kochujang (red pepper paste) and chungkukjang were prepared, irradiated at 0, 5, 10 and 20 kGy, and their compositions of free amino acid, free fatty acid and organic acid were determined. Compositions of free amino acid and free fatty acid in gamma irradiated sample were stable compared to non-irradiated control. Content of citric acid and succinic acid increased, while that of malic acid decreased in the gamma irradiated chungkookjang, but there were no significant changes in organic acid composition in organic and kochujang.

• The Korean Journal of Malacology
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• v.27 no.3
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• pp.247-252
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• 2011

The effect of ${\gamma}$-ray irradiation on the color of nucleus and cultured pearls was investigated. After ($^{60}Co$) ${\gamma}$-ray irradiation on the pearl nucleus, its color was altered from brownish to blackish brown or gray depending on irradiation dose. It was clearly found that the all samples are composed of aragonite. ESR spectra were based on the measurement of the paramagnetic species $CO_2$-radicals by the interaction with the ${\gamma}$-ray irradiation in $Mn^{2+}$ containing $CaCO_3$. In this study, we investigated optimal detection method of ${\gamma}$-ray irradiation to establish destructive or non-destructive test for pearl nucleus.

• Korean Journal of Plant Resources
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• v.27 no.5
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• pp.429-438
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• 2014

This study was designed to investigate the effects on anti-oxidative activities and increasing extraction yield of Aralia elata Cortex by gamma irradiation. Electron spin resonance (ESR) analysis as physical techniques for irradiation identification of Aralia elata showed that a pair of peak appeared on a space of 6.0 mT at the left and right of symmetric unspecific central ESR spectrums, confirming that the plant was gamma-irradiated. The optimum extracting conditions for preparing gamma irradiated samples from Aralia elata Cortex were to extract with 50% ethanol for 15 hrs after 10 kGy irradiation. DPPH scavenging activity and ABTS radical cation inhibitory activity of the water and 50% ethanol extracts from non irradiated and irradiated Aralia elata Cortex was very high as over 80% and 98%, respectively, at tested low concentration of $50{\mu}g/mL$. Antioxidant protection factor (PF) as anti-oxidation indicator of lipophilic compounds showed a very high level of activity as 2.18~2.78 PF. As for TBARs, water and ethanol extracts showed high level. Increase of TBARs inhibitory activity of water extracts was not shown by gamma-ray irradiation but ethanol extracts showed slight increasement of TBARs inhibitory activity with 10 kGy gamma-ray irradiation. These results shown confirmed increasement of extraction yield for phenolic compounds and anti-oxidative activity from Aralia elata. Thus, the treatment of gamma-irradiation can be used a way to amplify a solubility for biological active compounds and anti-oxidative activity in plants.

• Korean Journal of Veterinary Research
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• v.33 no.4
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• pp.649-655
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• 1993

A series of experiments on the effects of ${\gamma}-irradiation$ was performed to reveal the pathogenicity of ${\gamma}-irradiated$ oocysts of E tenella from Cobalt-60 and its progeny. The SPF chickens were inoculated with differnt doses of radiation and inoculum. The level of 100 Gy ${\gamma}-irradiation$ from $^{60}Co$ and the level of inoculum with $1{\times}10^4$ oocysts were recognized more pathogenic than those of the other groups by comparison of body weight gains, blood in feces and lesion scores. The signs of blood in feces, lesion score and the number of excreted oocysts in the feces were revealed as the lowest in the group of the ${\gamma}-irradiated$ oocysts, the average in the group of the 1st and the 3rd progeny, and the highest in the group of non-irradiated oocysts of E $tenell\grave{a}$. The body weight gain of the group immunized with ${\gamma}-irradiated$ oocysts of E tenella was higher than those of the non-irradiated, the 1st and 3rd progeny groups. The body weight gain of the groups immunized with the 1st and the 3rd progeny of E tenella were higher than that of the non-irradiated group. The feed conversion ration of the group immunized with ${\gamma}-irradiated$ oocysts of E tenella was lower than those of the non-irradiated, the 1st and the 3rd progeny groups. The feed conversion ratios of the group immunized with the 1st and 3rd progeny of ${\gamma}-irradiated$ oocysts were lower than that of the group infected with non-irradiated E tenella. The anticoccidial index(ACI 190.6) in the chickens immunized with the ${\gamma}-irradiated$ oocysts of E tenella and those(ACI 142.8 and 107.4) of the 1st and the 3rd progeny groups were higher than that (ACT 87.4) of the group infected with non-irradiated E tenella. It was thought that the pathogenicity of ${\gamma}-irradiated$ E tenella would be recovered according to increase the number of generation passaged in chicken.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.7
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• pp.964-969
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• 2009

To improve hygienic quality of vegetable fresh juice containing non-thermal process materials, an irradiation technology ($0{\sim}5\;kGy$) was applied and microbiological and physicochemical changes were evaluated during storage. The initial number of total aerobic bacteria of vegetable fresh juice containing non-thermal process materials was $4.8{\times}10^3\;CFU/mL$ and the number was increased during storage. At day 7, the number reached $3.0{\times}10^5\;CFU/mL$. However, the samples gamma-irradiated at $1{\sim}5\;kGy$ were $1.2{\times}10^2{\sim}1.0{\times}10^3\;CFU/mL$, which was lower than that of control and higher than 3 kGy irradiation, showing more than a decimal reduction. The lightness and yellowness of irradiated sample was higher than control but no difference was found among storage days; whereas, redness was decreased by gamma irradiation with no difference found among storage days. Ascorbic acid and carotenoid contents were decreased by irradiation treatment and increase of storage days. There were no changes in flavonoid contents; however, the content of polyphenols was increased by irradiation of sample.

• Korean Journal of Food Science and Technology
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• v.32 no.5
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• pp.1128-1134
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• 2000

This study was carried out to evaluate quality properties of gamma-irradiated Kwamegi prepared from Cololabis seira semi-dried by cold sea wind. Edible portion of Kwamegi was prepared from whole body, vacuum-packaged, gamma-irradiated in the doses of 3 or 5 kGy, and stored at $5^{\circ}C$ for 60 days. Volatile basic nitrogen and trimethylamine contents were not different by gamma irradiation. During storage increase of those two compounds were inhibited depending upon the dose. Thiobarbituric acid values did not differ in all samples, regardless of irradiation and storage. The amount of total volatile compounds of Kwamegi decreased by irradiation. Rheological properties were not affected by irradiation and were maintained up to 60 day when the Kwamegi was irradiated at 5 kGy dose, but those of control was softened. Sensory evaluation had no differences in all samples immediately after irradiation. Sensory quality of Kwamegi irradiated were organoleptically adequate, however that of control was deteriorated. In conclusion, these results indicate that gamma irradiation technique can be used to maintain the quality of Kwamegi.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2009.10a
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• pp.217-217
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• 2009

여러 금속 전구체가 함유된 금속염 용액에 광조사가 이루어지면 광환원에 의해 금속 나노입자 형성이 가능하다. 고에너지의 감마선($\gamma$-ray) 조사를 통해 단일 나노선과 평판 기판상에 Pt 나노입자를 형성시켰으며, Pt 금속염 용액과 감마선 조사 조건에 따른 Pt 나노입자의 크기와 형성 거동을 조사하였다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.10a
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• pp.705-707
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• 2017

Stereo-based spatial radiation detection devices can obtain not only spatial distribution information about the radiation source but also distance information from the detection device to the source. And it provides more efficient information on the source than the existing radiation imaging device. In order to provide high-speed information on the spectrum and type of gamma-ray source, a high-sensitivity detection sensor with high sensitivity is required, and a technique capable of solving the saturation phenomenon at a high dose is needed. In this paper, we constructed a high sensitivity sensor for the measurement of multiple gamma - ray spatial distributions using improved function of detection module to solve saturation to high dose and conducted research to increase the scope of a single detector. The result of this paper improves the performance of gamma ray.

• Journal of the Korean Society of Radiology
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• v.16 no.7
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• pp.953-960
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• 2022

The measurement of branching ratio of ¹⁶⁷Yb radioactive isotopes from gamma-ray spectrum of ¹⁶⁹Tm(p,3n)¹⁶⁷Yb reaction were performed by using a 100-MeV proton linear accelerator of the Korea Multi-purpose Accelerator Complex (KOMAC). The ¹⁶⁷Yb isotope has a half-life of 17.5 minutes and decays to ¹⁶⁹Tm. The gamma rays generated from the ¹⁶⁷Yb isotope were measured using an HPGe detector gamma ray spectroscopy system. The energy calibration of the detector and the efficiency measurement of the detector were determined using a standard source. The gamma rays of known main energy (62.9, 106.2, 113.3, 143.5 and 176.3 keV) were measured. On the other hand, information about the intensity of the generated gamma rays is very inaccurate. Therefore, in this study, the decay strength of the main gamma rays was accurately measured. Overall, it was different from the previously known results, and in particular, it was found that the intensity of the main decay gamma ray, such as the 113.3 and 106.2 keV gamma ray, was overestimated, and it was found that the gamma ray, such as 62.9, 116.7 and 143.5 keV was underestimated. The present results are considered to be important information in the fields of nuclear fusion, astrophysics and nuclear physics in the future.

• 대한방사선방어학회:학술대회논문집
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• 2010.04a
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• pp.186-187
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• 2010