• Title/Summary/Keyword: Irradiation Effects

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Effects of Cobalt-60 γ Irradiation on the Growth of Rabbits (Cobalt-60 gamma 선(線) 조사(照射)가 가토(家兎)의 성장(成長)에 미치는 영향(影響))

  • Sung, Jai Ki
    • Korean Journal of Veterinary Research
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    • v.12 no.1
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    • pp.1-5
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    • 1972
  • In oder to investigate the effects of cobalt-60 gamma ray irradiation on the body gains of rabbits aging approximately 50-day-old rabbits were subjected to single whole-body gamma irradiation externally. The results obtained were as follows: 1. There were significant differences of the body gains between control and treated groups except the 100 rads gamma-rays exposure group. 2. There were no differences in body gains between male and female rabbits. 3. Generally, the relation between gamma irradiated doses and the growth rates of rabbits were inversly proportional. 4. The $LD_{50}$ of the rabbits was 600 rads in case of single external whole-body gamma irradiation.

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Variations of the Electrical Treeing and Breakdown Characteristics on LDPE Due to Gamma-ray Irradiation

  • Lee, Chung;Ryu, Boo-Hyung
    • International Journal of Safety
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    • v.8 no.1
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    • pp.14-17
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    • 2009
  • The $Co^{60}$ $\gamma$-ray irradiation effects on the electrical and thermal characteristics of low density polyethylene crosslinked by 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 with increasing dosage. Also, chemical analyses were performed TGA, gel fraction. These electrical properties changed depending upon its crosslinking degree and byproducts from crosslinking reactions. Crosslinking reactions were considered causing by $\gamma$-ray irradiation and DCP had contained in low density polyethylene.

Effects of Gamma-Irradiation on the Water Absorption Property of Black Soybeans (감마선 조사가 검정콩의 수분흡수 특성에 미치는 영향)

  • 김종군
    • Journal of the Korean Home Economics Association
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    • v.30 no.3
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    • pp.101-117
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    • 1992
  • Effects of gamma irradiation(2.5∼20kGy) on water absorption property was studied for a local variety of black soybeans. In water absorption patterns of black soybeans, the time to reach a fixed moisture content was reduced depending on the increment of water soaking temperature and irradiation dose. Irradiation at 2.5∼10kGy resulted in the reduction of soaking time of black soybeans by about 1∼3 hours and the increase of hydration capacity by 10∼20%, respectively, compared to the nonirradiated control black soybean. The water uptake rate constant of the irradiated black soybean difinitely increased with the increase of dose levels and water soaking temperature. The activation energy for water absorption and z-value were lower in the irradiated black soybeans than in the nonirradiated control black soybean. The efficacy of water absorption property in the irradiated black soybeans was also recognized after one year of storage at room temperature.

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Effects of Low Incident Energy Levels of Infrared Laser Irradiation on the Proliferation of Candida Albicans Part III : A Study on the Interval of Irradiation

  • Sam-Kun Kim;Phil-Yeon Lee;Ki-Suk Kim
    • Journal of Oral Medicine and Pain
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    • v.19 no.1
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    • pp.25-31
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    • 1994
  • This study was performed to investigate the biostimulation effects of low level laser therapy (LLLT) on the fungus, Candida alvicans, according to the interval of irradiation during the cell cycle. Samples were divided into 5 groups which were P7-2Hr, P7-4Hr, P15-2Hr, P15-4Hr and Co. Sample was irradiated for 1 minute with 2 hours or 2 minutes with 4 hours of elapsed time during 28 hours of the cell cycle of Candida albicans, and the optical density was assessed by spectrophotometry every 2 hours. It was found that there was significant difference, in the cell growth, between 2 hour and 4 hour interval laser irradiation, although the total energy of each group using identical pulse during exam was equal.

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Effects of Sensory Qualities of Ready-to-Eat Chicken Cooked by Different Culinary Methods and Gamma-irradiated at 10 kGy (조리 방법별 즉석 취식 닭고기의 조리 직후 감마선 조사가 관능적 품질에 미치는 영향)

  • Park, Kyung-Sook
    • Journal of Radiation Industry
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    • v.6 no.4
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    • pp.311-316
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    • 2012
  • The purpose of this study was to compare the sensory effects of different culinary methods such as electric pan cooking and charcoal roasting on gamma irradiated ready-to-eat chicken at 10 kGy. Evlauation of sensory properties were measured by estimating the organoleptic characteristics and physicochemical properties (TBARS, hardness and color different matters). The results showed that gamma irradiation after charcoal-roasting could more effectively moderate the decrease of sensory qualities and reduce off-flavor of ready-to-eat chicken than gamma irradiation after following electric pan cooking. These results suggest that gamma irradiation after charcoal broiling can be an effective culinary method for the preparation of ready-to-eat chicken.

Molecular Weight Control of Chitosan Using Gamma Ray and Electron Beam Irradiation

  • Kim, Hyun Bin;Lee, Young Joo;Oh, Seung Hwan;Kang, Phil Hyun;Jeun, Joon Pyo
    • 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.

An Experimental Study on the Effects of Hyperthermia and Irradiation on the Rat's Kidney (방사선조사와 온열요법이 백서신에 미치는 조직 변화에 관한 실험적 연구)

  • Yoo, Myung-Hee;Lee, Kyung-Ja;Rhee, Chung-Sik
    • Radiation Oncology Journal
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    • v.7 no.2
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    • pp.157-169
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    • 1989
  • Radiological and clinical evidences indicate that hyperthermia combined with irradiation produce a significant improvement in therapeutic effect of cancer The experiences obtained from 90 rats' kidney A single dose of irradiation ranged from 6Gy, 8Gy and 10Gy was delivered on the rat's kidney. The combined therapy group had the same irradiation after hyperthermia at $42\~44^{\circ}C$ for 30 minutes. Microscopic examination and calculation of thermal enhancement ratio were carried out, and the results were as follows: 1. In the group of hyperthermia alone, there were moderate glomerular congestion and mild tubular degeneration on light microscopic examination. 2. In the group of irradiation alone, tubular degeneration was noted in 6Gy irradiation and its severity was increased along with radiation dose. 3. In the group of hyperthermia combined with irradiation, tubular degeneration and necrosis were appeared in 6Gy and 10Gy irradiation, respectively. 4. On electron microscopic examination, proximal convoluted tubular and glomerular changes in irradiation group were similar to that of combined with hyperthermia, and its severity was increased along with observation periods. 5. Thermal enhancement ratio (TER) was 1.0 after evaluation of histipathologic changes in rat's kidney, with combination therapy.

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Dose Effect of Phytosanitary Irradiation on the Postharvest Quality of Cut Flowers

  • Kwon, Song;Kwon, Hye Jin;Ryu, Ju Hyun;Kim, Yu Ri
    • 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.

Effects of whole-body gamma-irradiation on the peripheral blood of ICR mouse (ICR 마우스에서 방사선 조사 용량에 따른 혈액변화의 관찰)

  • Kim, Sung-Ho;Lee, Jong-Hwan;Kim, Se-Ra;Lee, Hae-June;Lee, Yun-Sil;Kim, Tae-Hwan;Ryu, Si-Yun;Jo, Sung-Kee;An, Mi-Yeong
    • Korean Journal of Veterinary Research
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    • v.42 no.2
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    • pp.183-190
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    • 2002
  • The effects of ionizing radiation on the peripheral blood elements of ICR mouse were examined after varying doses of whole-body gamma-irradiation. ICR mice (n=50) were exposed to 0, 2, 4, 6 and 8 Gy gamma-ray ($^{60}Co$) at 10 Gy/min. The animals were studied for their hematological response on days, 3, 7, 14, 21, 42 and 56 post irradiation. No significant change was noted in erythrocyte, hemoglobin and hematocrit values after irradiation with dose of 2 Gy. Decreasing erythrocyte, hemglobin and hematocrit values occured after irradiation with doses of more than 4 Gy on day 7 after irradiation followed by a sharp fall on day 14. A recovery in these values was noted after 3 weeks of irradiation. Thrombocyte counts decreased on day 3, reaching minimal values on day 7. The total number of leukocytes was reduced on day 3, mainly because of a decrease in the lymphocyte population. An evident lymphopenia and neutropenia occur almost on the day 3 and last up to the day 28 after irradiation. All of the hematological values decreased in the blood in a dose-dependent manner at the same time.

Effects of Ozone Treatment and Gamma Irradiation on the Quality Properties of Dried-Spirullina and Dried-Sea Tangle Powders (오존처리와 감마선 조사가 스피루리나와 다시마 분말의 품질특성에 미치는 영향)

  • Byun, Myung-Woo;Yook, Hong-Sun;Kwon, Oh-Jin;Jo, Sung-Kee;Lee, Sung-Hee
    • Korean Journal of Food Science and Technology
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    • v.29 no.4
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    • pp.764-770
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    • 1997
  • For the purpose of improving hygienic quality of dried-spirullina and dried-sea tangle powders as raw materials of health food, the comparative effects of ozone treatment and gamma irradiation on the microbial and physicochemical properties were investigated. Gamma irradiation at 7.5 kGy resulted in sterilization of total aerobic bacteria, coliforms and molds below detective levels $(<10^{1}\;CFU/g\;sample)$, while ozone treatment for 8 hr up to 18 ppm could not sufficiently eliminate the microorganisms of the samples. Physicochemical properties including compositions of fatty acid and amino acid, minerals, pH and natural pigments were not changed by gamma irradaition up to 10 kGy, whereas, ozone treatment caused changes in pH, TBA value, natural pigments and fatty acid compositions. Especially, ozone treatment markedly decreased unsaturated fatty acid of the samples.

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