• Title/Summary/Keyword: $^{232}Th$

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Derivation of On-site Major Exposure Factor using NDD Analysis when Landfilling NORM Waste (NORM 폐기물 매립 시 NDD 분석을 활용한 부지 내 주요 피폭인자 도출)

  • Ji Hyeon Lim;Shin Dong Lee;Geon Woo Son;Kwang Pyo Kim
    • Journal of Radiation Industry
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    • v.18 no.3
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    • pp.183-193
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    • 2024
  • As part of the social response to the radon bed incident in 2018, the Nuclear Safety and Security Commission took measures to collect and dispose of all radon beds. The Waste Management Act provides landfill disposal as one of the disposal methods for natural radioactive product waste, which is one of the NORM wastes. When NORM wastes are landfilled, workers and the public at the landfill site are exposed to radiation through various pathways, such as leaching of radionuclides through soil and groundwater, and multiple exposure factors are involved simultaneously. In order to improve the reliability of radiological impact assessment, the values of main exposure factors should be selected more accurately. Therefore, before developing the main exposure factors for site characteristics, it is necessary to prioritize main exposure factors reflecting domestic characteristics of NORM waste landfills. Therefore, in this study, the main exposure factors for NORM waste landfill were derived using NDD analysis. To derive the main exposure factors, the analysis tool was first selected as RESRAD-ONSITE computer code, and the exposure scenarios were mainly selected as a resident farmer and suburban resident scenario, recreation scenario, and industrial worker scenario. Then, the priority 1 and 2 factors were selected for sensitivity analysis, and a Korean standard model was established to reflect Korean characteristics. Finally, the sensitivity analysis was conducted through NDD, and the main exposure factors were derived based on this. In the resident farmer scenario, the contaminated zone distribution coefficients of 226Ra, 210Pb, 232Th, 228Ra, 234U, and 238U, as well as precipitation and evapotranspiration factors, were derived as the main exposure factors. In the suburban resident scenario, the contaminated zone distribution coefficients of 226Ra, 210Pb, 232Th, 228Ra, 234U, and 238U, as well as precipitation and evapotranspiration coefficients, were derived as the main exposure factors. In the recreation scenario, the contaminated zone distribution coefficient of 232Th was derived as the main exposure factor. For the industrial worker scenario, the erosion rate was derived as the main exposure factor. The main exposure factors for each scenario were analyzed to be different depending on the scenario characteristics. The results of this study can be utilized as a basis for radiological environmental impact assessment of NORM waste landfill in Korea.

A Feasibility of Once-Through Thorium Fuel Cycle for PWR (가압경수로에서 비순환 토륨 핵연료 주기의 적용 타당성)

  • 우일탁;김명현
    • Proceedings of the Korea Society for Energy Engineering kosee Conference
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    • 1999.11a
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    • pp.131-136
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    • 1999
  • 토륨은 자연계에서 유일한 동위원소인 Th-232로 존재하며 반감기는 1.4$\times$$10^{10}$년으로 U-238의 4.5$\times$$10^{9}$년에 비하여 약 3배 길고 매장량도 약 3배 많은 것으로 알려져 있다. 토륨은 원자력 초기 개발단계인 1950년대부터 우라늄에 관한 연구와 함께 시작되었지만, 70년대 중반 이후로는 토륨 핵연료 재처리의 어려움과 여러 정치적 이유로 이에 관한 연구가 거의 중단되었다.(중략)

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Studies on the induction of pregnancy and the number of fetuses during pregnancy in rats

  • Choi, Seung-Hee;Cho, Yong-Seong;Kim, Min-Ji;Lee, Chae-Hyeok;Seong, Hwan-Hoo;Baek, Soon-Hwa;Lee, Jang-Hee
    • Journal of Animal Reproduction and Biotechnology
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    • v.35 no.3
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    • pp.232-238
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    • 2020
  • This study used adult wistar-based rats to observe the sexual cycle as a morphological characteristic of vaginal epithelial cells by vaginal smearing, and investigated the fetal number through mating with male rats of the same strain. The target animal was a 12 to 13-week-old Wistar-based mature unlighted rat (weight 220 g to 240 g), room temperature 23 ± 2℃, 14 hours artificial lighting (05:00 to 19:00 hours), 10 hours Adapted individuals were used for rearing for at least 2 weeks under the conditions of the darkroom (19:00 to 05:00). The feed was managed for free feeding of pellet feed for animals and water. The vaginal smearing method was used for the experiments by observing the sexual cycle every morning and confirming that the normal sexual cycle of 4 or 5 days was repeated at least 2 cycles or more. As a result, the proestrus was found to have few red blood cells, the cells and nuclei were rather large and round, and many nucleated cells were identified. In the case of the estrus, the cells were large and the nuclei were not stained, and most of the keratinocytes were found. In addition, in the metestrus and diestrus, there were many white blood cells, and it was confirmed that nucleated epithelial cells and keratinocytes were significantly reduced. The pregnancy period was 21 ± 1.8 days, and the number of live births per delivery was 11.9 on average. The number of fetuses on the 8th and 10th days of pregnancy were 15.2 ± 0.4 and 15.4 ± 0.3, respectively. On the contrary, the number of fetuses on the 12th day of pregnancy was 12.9 ± 0.6, which was significantly (p < 0.05) decreased compared to the 10th day of pregnancy, and the number of fetuses was similar until delivery. As a result of investigating the change of body weight according to the birth weight and growth stage after delivery, the birth weight of female and male was 9.2 ± 2.0 g and 9.8 ± 2.5 g, respectively. After that, until the 16th day, the female and the male showed similarly moderate weight gain, and then showed a rapid weight gain until the 21st day of lactation. With reference to the results of this study, it is expected to be used as basic data for determining the mating time of rodents and controlling pregnancy and fetal number.

일본(日本) 패션의 미적(美的) 특성(特性)에 관(關)한 연구(硏究) -<모드 자포니슴>을 중심(中心)으로-

  • Cho, Kyu-Hwa
    • Journal of Fashion Business
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    • v.11 no.4
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    • pp.232-246
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    • 2007
  • The purpose of this study is to investigate aesthetic characteristics and aesthetic consciousness of the style that European fashion(Paris, London, Netherlands) has accepted the since $19^{th}$ century. The mode Japonisme's development process in around $20^{th}$ century and 21st century has 6 characteristics as follows; 1. Accepting kimono as dressing gown 2. Accepting kimono as Japanese style's objet of Japanese taste 3. Accepting Japanese textile's skills, patterns, and asymmetry. 4. Accepting kimono's formative nature : flat pattern, flexibility, style etc. 5. Shocking of Japanese style's beauty 6. Accepting characters and casual wear Japanese aesthetic consciousness expressed on unconstructed design or deconstructed design that is the aesthetic characteristic of Japanese fashion is , , and the aesthetic consciousness expressed on Zen(Seon) style, cartoons of character fashion, and costume play is .

The Relationship between Children's Gender role Attitude and Social Competency (아동의 성역할 태도와 사회적 능력간의 관계)

  • 이경희
    • Journal of the Korean Home Economics Association
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    • v.35 no.1
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    • pp.47-58
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    • 1997
  • The purpose of this study was to investigate the relationship between children's gender role attitude measured by component model and social competency. Subjects were 232 elementary school children: 113 4th graders and 119 6th graders. The main results were as follows. First there were significant differences in mean scores of gender role attitude with age and sex variable. And among three dimensions of component model(i.e, gender label-component links within-component links between-component links) the difference was most discriminant in gender label-component links. Second there were significant relationship between gender role attitude and social competency. Among three dimensions of gender role attitude the most predictor variable for social competency was gender label-component links. And among four dimensions of social competency the most effective criterion variable for gender role attitude was leadership. And there were significant differences in social competency score with mother's educational level and sex of children as well as gender role attitude. In conclusion children's gender role attitude influence their social competency. More flexible gender role attitude they have more improved in their social competency , especially in boys.

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Chuna therapy include Space Spinal Conduction Exercise and Manipulation Treatment for Functional dyspepsia patients: A case report (공간척추도인안교법의 타교법을 병행한 추나 치료만으로 증상 호전을 보인 기능성 소화불량 환자 1례)

  • Myung-hwan Yu;Jae-Heung Cho
    • The Journal of Korean Medicine
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    • v.45 no.1
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    • pp.225-232
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    • 2024
  • Objectives: The purpose of this case study was to report the effect of Chuna therapy include Space Spinal Conduction Exercise and Manipulation Treatment for Functional dyspepsia patients. Methods: A 32-years-old male patients with functional dyspepsia visited the clinic ten times from March 17th 2023 to April 22th 2023. To assess the treatment outcomes, we used the Standard tool for pattern identification of Functional dyspepsia and Nepean Dyspepsia Index-Korean version (NDI-K) symptom score. Result: After treatment, Standard tool for pattern identification of Functional dyspepsia and Nepean Dyspepsia Index-Korean version (NDI-K) score decreased. Conclusion: Chuna therapy include Space Spinal Conduction Exercise and Manipulation Treatment was effective in the treatment of patient with Functional dyspepsia.

DEVELOPMENT OF LEAD SLOWING DOWN SPECTROMETER FOR ISOTOPIC FISSILE ASSAY

  • Lee, YongDeok;Park, Chang Je;Ahn, Sang Joon;Kim, Ho-Dong
    • Nuclear Engineering and Technology
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    • v.46 no.6
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    • pp.837-846
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    • 2014
  • A lead slowing down spectrometer (LSDS) is under development for analysis of isotopic fissile material contents in pyro-processed material, or spent fuel. Many current commercial fissile assay technologies have a limitation in accurate and direct assay of fissile content. However, LSDS is very sensitive in distinguishing fissile fission signals from each isotope. A neutron spectrum analysis was conducted in the spectrometer and the energy resolution was investigated from 0.1eV to 100keV. The spectrum was well shaped in the slowing down energy. The resolution was enough to obtain each fissile from 0.2eV to 1keV. The detector existence in the lead will disturb the source neutron spectrum. It causes a change in resolution and peak amplitude. The intense source neutron production was designed for ~E12 n's/sec to overcome spent fuel background. The detection sensitivity of U238 and Th232 fission chamber was investigated. The first and second layer detectors increase detection efficiency. Thorium also has a threshold property to detect the fast fission neutrons from fissile fission. However, the detection of Th232 is about 76% of that of U238. A linear detection model was set up over the slowing down neutron energy to obtain each fissile material content. The isotopic fissile assay using LSDS is applicable for the optimum design of spent fuel storage to maximize burnup credit and quality assurance of the recycled nuclear material for safety and economics. LSDS technology will contribute to the transparency and credibility of pyro-process using spent fuel, as internationally demanded.

Assessment of radionuclides from coal-fired brick kilns on the outskirts of Dhaka city and the consequent hazards on human health and the environment

  • M.M. Mahfuz Siraz;M.D.A. Rakib;M.S. Alam;Jubair Al Mahmud;Md Bazlar Rashid;Mayeen Uddin Khandaker;Md. Shafiqul Islam;S. Yeasmin
    • Nuclear Engineering and Technology
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    • v.55 no.8
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    • pp.2802-2811
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    • 2023
  • In a first-of-its-kind study, terrestrial radionuclide concentrations were measured in 35 topsoil samples from the outskirts of Dhaka using HPGe gamma-ray spectrometry to assess the radiological consequences of such a vast number of brick kilns on the plant workers, general as well as dwelling environment. The range of activity concentrations of 226Ra, 232Th, and 40K is found at 19 ± 3.04 to 38 ± 4.94, 39 ± 5.85 to 57 ± 7.41, and (430 ± 51.60 to 570 ± 68.40) Bq/kg, respectively. 232Th and 40K concentrations were higher than the global averages. Bottom ash deposition in lowlands, fly ash buildup in soils, and the fallout of micro-particles are all probable causes of the elevated radioactivity levels. 137Cs was found in the sample, which indicates the migration of 137Cs from nuclear accidents or nuclear fallout, or the contamination of feed coal. Although the effective dose received by the general public was below the recommended dose limit but, most estimates of hazard parameters surpass their respective population weighted global averages, indicating that brick kiln workers and nearby residents are not safe due to prolonged exposures to terrestrial radiation. In addition, the soil around sampling sites is found to be unsuitable for agricultural purposes.

Assessment of Radiological Hazards in Some Foods Products Consumed by the Malian Population Using Gamma Spectrometry

  • Adama Coulibaly;David O. Kpeglo;Emmanuel O. Darko
    • Journal of Radiation Protection and Research
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    • v.48 no.2
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    • pp.84-89
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    • 2023
  • Background: Food consumption is one of the most important routes for radionuclide intake for the public; therefore, there is the need to have a comprehensive understanding of the amount of radioactivity in food products. Consumption of radionuclide-contaminated food could increase potential health risks associated with exposure to radiation such as cancers. The present study aims to determine radioactivity levels in some food products (milk, rice, sugar, and wheat flour) consumed in Mali and to evaluate the radiological effect on the public health from these radionuclides. Materials and Methods: The health impact due to ingestion of radionuclides from these foods was evaluated by the determination of activity concentration of radionuclides 238U, 232Th, 40K, and 137Cs using gamma spectrometry system with high-purity germanium detector and radiological hazards index in 16 samples collected in some markets, mall, and shops of Bamako-Mali. Results and Discussion: The average activity concentrations were 9.8±0.6 Bq/kg for 238U, 8.7±0.5 Bq/kg for 232Th, 162.9±7.9 Bq/kg for 40K, and 0.0035±0.0005 Bq/kg for 137Cs. The mean values of radiological hazard parameters such as annual committed effective dose, internal hazard index, and risk assessment from this work were within the dose criteria limits given by international organizations (International Commission on Radiological Protection and United Nations Scientific Committee on the Effects of Atomic Radiation) and national standards. Conclusion: The results show low public exposure to radioactivity and associated radiological impact on public health. Nevertheless, this study stipulates vital data for future research and regulatory authorities in Mali.