• Radiation Oncology Journal
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• 제12권2호
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• pp.219-223
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• 1994

This paper describes the basic data measurements for total body irradiation with 6 Mv photon beam including compensators design. The technique uses bilateral opposing fields with tissue compensators for the head, neck, lungs, and legs from the hip to toes. In vivo dosimetry was carried out for determining absorbed dose at various regions in 7 patients using diode detectors(MULTIDOSE,k Model 9310, MULTIDATA Co., USA). As a results, the dose uniformity of${\pm}3.5{\%}$(generally, within${\pm}10{\%}$can be achieved with out total body irradiation technique.

• 대한가정학회지
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• 제30권3호
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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.

• 한국식품위생안전성학회지
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• 제9권3호
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• pp.151-161
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• 1994

Gamma irradiation was applied to red ginseng for improving its quality. Irradiation at 5~7 kGy was effective for sterilizing all contaminated microorganisms of red ginseng. At the dose levels, no significant shanges in physicochemical properties (color, saponin, lipid rancidity and fatty acids etc.) were observed even after 6 months storage. Gamma irradiation was also effective for the improving hygienic quality of packed red ginseng with high moisture content (up to 20%), without any quality deterioration.

• Nuclear Engineering and Technology
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• 제54권1호
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• pp.255-261
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• 2022

A reliable and well-characterized dosimetry system which is traceable to the international measurement system, is the key element to quality assurance in radiation processing with cobalt-60 gamma rays, X-rays, and electron beam. This is specifically the case for health-regulated processes, such as the radiation sterilization of single use medical devices and food irradiation for preservation and disinfestation. Polyethylene is considered to possess a lot of interesting dosimetric characteristics. In this work, a detailed study has been performed to determine the dosimetric characteristics of a commercialized high-density polyethylene (HDPE) film using Fourier transformed infrared spectrometry (FTIR). Correlations have been established between the absorbed dose and radiation induced infrared absorption in polyethylene having a maximum at 965 cm^-1 (transvinylene band) and 1716 cm^-1 (ketone-carbonyl band). We have found that polyethylene dose-response is linear with dose for both bands up to1000 kGy. For transvinylene band, the dose-response is more sensitive if irradiations are made in helium. While, for ketone-carbonyl band, the dose-response is more sensitive when irradiations are carried out in air. The dose-rate effect has been found to be negligible when polyethylene samples are irradiated with electron beam high dose rates. The irradiated polyethylene is relatively stable for several weeks after irradiation.

• 농업생명과학연구
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• 제45권1호
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• pp.89-99
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• 2011

진공포장 한 건조발효햄에 감마선을 조사 (0, 2.5, 5, 7.5, 10 kGy)하여 저장 3개월 동안 이화학적 품질 (육색, 지방산패도, 염기태 질소화합물, pH) 및 미생물 (총균, 유산균) 생육특성을 평가하였다. 감마선 조사는 선량이 높을수록 시료의 표면 육색인 적색도 (a*)와 관능적 육색 및 기호도를 저하시켰다. 반면에 pH, 지방산패도, 염기태 질소화합물, 수분활성도에 큰 영향을 미치지 않은 것으로 나타났다. 미생물적 측면에서는 감마선 조사 수준이 높을수록 미생물학적 품질이 개선되었다. 관능적 측면인 풍미에서는 저장기간 및 처리구간에 유의적 차이는 나타나지 않았지만 육색 측면에서는 5 kGy 이상에서는 낮은 평점을 나타내었다. 따라서 건조발효햄의 저장기간을 고려할 때 미생물학적 및 이화학적 품질은 5 kGy 수준의 감마선 조사에 의해 개선되는 것으로 나타났다.

• 상하수도학회지
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• 제33권6호
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• pp.469-480
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• 2019

This study was conducted to evaluate the degradation and mineralization of PPCPs (Pharmaceuticals and Personal Care Products) using a CBD(Collimated Beam Device) of UV/H₂O₂ advanced oxidation process. The decomposition rate of each substance was regarded as the first reaction rate to the ultraviolet irradiation dose. The decomposition rate constants for PPCPs were determined by the concentration of hydrogen peroxide and ultraviolet irradiation intensity. If the decomposition rate constant is large, the PPCPs concentration decreases rapidly. According to the decomposition rate constant, chlortetracycline and sulfamethoxazole are expected to be sufficiently removed by UV irradiation only without the addition of hydrogen peroxide. In the case of carbamazepine, however, very high UV dose was required in the absence of hydrogen peroxide. Other PPCPs required an appropriate concentration of hydrogen peroxide and ultraviolet irradiation intensity. The UV dose required to remove 90% of each PPCPs using the degradation rate constant can be calculated according to the concentration of hydrogen peroxide in each sample. Using this reaction rate, the optimum UV dose and hydrogen peroxide concentration for achieving the target removal rate can be obtained by the target PPCPs and water properties. It can be a necessary data to establish design and operating conditions such as UV lamp type, quantity and hydrogen peroxide concentration depending on the residence time for the most economical operation.

• 치과방사선
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• 제15권1호
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• pp.27-40
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• 1985

This study was undertaken to observe the histopathologic changes in salivary gland of the white rats when exposed to megavoltage fractionated dose of cobalt-60 irradiation and 78 female white rats, weighing approximately 180gm, were divided into control and 3 experimental groups. Irradiation on experimental groups was delivered by using 6000 curies MeV ALCYON cobalt-60 teletherapy unit with exposure rate 183 rads per minute, in source skin distance 80cm, 600 rads every 3 days. In experimental groups, Group Ⅰwas irradiated of total dose 1200 rads for a period of 6 days, Group Ⅱ was irradiated of total dose 2400 rads for a period of 12 days and Group Ⅲ was irradiated of total dose of 4800 rads for a period of 24 days. The animals were sacrificed serially at 3 hours, 6 hours, 10 hours, 1st day, 4th day, 7th day after each completion of irradiation exposure. At sacrifice, salivary glands were excised and examined microscopically and electromicroscopically. The results were as follows: 1. The acinar cells of parotid and submaxillary gland showed damage varied with dose, 1200 rads resulted in very mild injury while 4800 rads caused most extensive injury. 2. The acinar cells of parotid and submandibular gland showed similar ultrastructural alterations, appeared as pleomorphic nucleus, decreased numbers and pleomorphism of secretory granules, distention of rough endplasmic reticulum, expansion and pallor appearance of mitochondria, and hypertrophy of Golgi complex. 3. Parotid serous cells were the most sensitive components, displaying morphological alterations of radiation damage as early as 3 hours, followed by submandibular seromucinous cells and secretory tubular cells. 4. The mucous cells of sublingual gland, as well as the whole ductal lining cells of each salivary gland, displayed no significant alterations. No evidence of microvascular injury through whole experimental groups indicated that microvascular impairment does not contribute to early salivary gland injury.

• 한국식품위생안전성학회지
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• 제1권1호
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• pp.39-46
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• 1986

Comparison of ethylene oxide(E.O) fumigation and gamma irradiation on the sterilization, microbiological, physicochemcial and sensory quality of dried fishery products (shucked shellfish and mussel powder) were investigated. The viable cell count of mesophilic total bacterial was reduced by over 2 to 3 log cycles with irradiation of 3 to 5 kGy, and those samples were completely sterilized by irradiation dose of 7 to 10 kGy. In view of reduction of microorganisms, D10 value of each samples were ranged from 1. 36-1. 46 kGy. fungi, mesophilic spores, acid tolerant bacteria and coliforms were sterilized at 5 to 7 kGy irradiation but E.O. fumigation proved insulfficient to eliminate the mesophilic total bacteria and fungi. In the physicochemical and sensory quality of samples, such as the amino acid, TBA value, TMA-N, color difference and overall acceptability irradiated sample with optimum dose was similar to those of the nonirradiated sample, while E.O. fumigated sample was remarkably deteriorated in the physicochemical and sensory quality of samples.

• 대한의생명과학회지
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• 제12권1호
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• pp.43-48
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• 2006

Present study aimed to investigate recovering effect of propolis on blood components and tissues of mouse after low dose irradiation. It is verified that the contents of Fe, Mg, P, Zn and Cu in propolis dosed blood are increased slightly than irradiated blood, however, the contents of Ba and Pb are decreased to one tenth than irradiated blood and the contents of Fe and P are increased to 10% than control group. We consider this result as the propolis acts a role of defence factor minimizing changes of elements caused by irradiation in blood. Among the blood components, Glutamate oxaloacetate transaminase (GOT) value is increased after the radiation but after dosed with propolis and irradiated the value is decreased, suggesting that propolis as a buffering material against irradiation. After dosed with propolis, a number of spermatogenic cells are lowered in testis tissue, however, nucleus and cytoplasm are clearly observed in spermatogonia, spermatocytes and spermatid cells. And nucleus and membrane of cells in the proximal convoluted tubule of renal tissue are clearly observed. Also, cytoplasmand membrane of surface mucous cells in stomach tissue are appeared in normal which is almost like those of control group. We consider that the propolis used in this study is preventing deformations of cells increasing resistance capacity against irradiation rather than recovering damaged tissues.

• 한국식품영양과학회지
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• 제30권3호
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• pp.500-504
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• 2001

Gamma irradiation was applied to reduce egg allergy. Ovalbumin (OVA), an egg white protein, was used as model allergen and was gamma-irradiated at 3, 5, or 10 kGy in an aqueous state (2.0 mg/mL). The changes in allergenic and antigenic properties of OVA resulted from gamma irradiation were monitored by ELISA with serum from egg-hypersensitive patients (H-IgE), and mouse monoclonal IgG (M-IgG) or rabbit polyclonal IgG (R-IgG). The binding ability of H-IgE to irradiated OVA was dose-dependently reduced. However, IgGs from animal did better recognize 3 or 5 kGy-irradiated OVA. In the evaluation of immune reactivity using blind test, the reactivity of H-IgE rapidly decreased depending upon the irradiation dose. However, the reactivities of M-IgG and R-IgG was higher at 5 and 3 kGy-irradiated OVA than non-irradiated control. The results provide a new possibility to use irradiation process for reducing the allergenicity of egg white.