• Title/Summary/Keyword: Dose Rate

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Effectiveness of the neutron-shield nanocomposites for a dual-purpose cask of Bushehr's Water-Water Energetic Reactor (VVER) 1000 nuclear-power-plant spent fuels

  • Rezaeian, Mahdi;Kamali, Jamshid;Ahmadi, Seyed Javad;Kiani, Mohammad Amin
    • Nuclear Engineering and Technology
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    • v.49 no.7
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    • pp.1563-1570
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    • 2017
  • In order to perform dry interim storage and transportation of the spent-fuel assemblies of the Bushehr Nuclear Power Plant, dual-purpose casks can be utilized. The effectiveness of different neutron-shield materials for the dual-purpose cask was analyzed through a set of calculations carried out using the Monte Carlo N-Particle (MCNP) code. The dose rate for the dual-purpose cask utilizing the recently developed materials of $epoxy/clay/B_4C$ and $epoxy/clay/B_4C/carbon$ fiber was less than the allowable radiation level of 2 mSv/h at any point and 0.1 mSv/h at 2 m from the external surface of the cask. By utilization of $epoxy/clay/B_4C$ instead of an ethylene glycol/water mixture, the dose rates on the side surface of the cask due to neutron sources and consequent secondary gamma rays will be reduced by 17.5% and 10%, respectively. The overall dose rate in this case will be reduced by 11%.

Experiment for Clinical Application with Photodiode (Photodiode를 사용한 측정기의 임상응용을 위한 실험)

  • Kim, You-Hyun;Kwon, Soo-Il;Huh, Joon
    • Journal of radiological science and technology
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    • v.19 no.2
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    • pp.71-77
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    • 1996
  • Studies were conducted to determine the clinical application of photodiode. We compared photodiode with ion-chamber as to change of tube potential, tube current, mAs and measured decreasing rate of penetration dose. When tube potential was changed from 60 kVp to 120 kVp, output of photodiode and ion-chamber were changed from 0.4 to 1.625, and 1.018 to 4.268, respectively. This was a good agreement to theory that $I=Kv^2it$(I is intensity, K is constant, v is tube potential, i is tube current, t is time). Characteristics for change of tube current and mAs were also a good agreement to theory. And comparison in decreasing rate of penetration dose was similar except above 6 cm in depth. Our results indicated that photodiode was a good instrument for relative measurement of radiation exposure, but we can not use the photodiode for absolute radiation dose.

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Decolorization of Rhodamine B Using Quartz Tube Photocatalytic Reactor (석영관 광촉매 반응기를 이용한 Rhodamine B의 색도 제거)

  • Park Young Seek
    • Journal of Environmental Health Sciences
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    • v.30 no.5 s.81
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    • pp.358-365
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    • 2004
  • The photocatalytic oxidation of Rhodamine B(RhB) was studied using photocatalytic reactor filled with module of quartz tube. Module of quartz tube consisted of small quartz tube (inner diameter, 1.5 mm; outer diameter, 3 mm) bundle coated with powder $TiO_2$ and uncoated large quartz tube (inner diameter, 20 mm; outer diameter, 22 mm). Two 30 W germicidal lamp was used as the light source and the reactor volume was 0.5 l. The effects of parameters such as the coating materials and numbers, initial concentration, $H_{2}O_2$ dose and metal deposition (Ag, Pt and Fe) and simultaneous application of $H_{2}O_2$ and metal deposition. The results showed that the initial reaction constant of quartz module coated with powder $TiO_2$ was higher 1.4 time than that of the $TiO_2$ sol and optimum coating number is twice. In order to increase reaction rate, simultaneous application of photocatalytic and photo-fenton reaction using Fe coating and dose $H_{2}O_2$ dose increased reaction rate largely.

Estimation of natural radionuclide and exhalation rates of environmental radioactive pollutants from the soil of northern India

  • Devi, Vandana;Chauhan, Rishi Pal
    • Nuclear Engineering and Technology
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    • v.52 no.6
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    • pp.1289-1296
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    • 2020
  • The estimation of radioactivity level is vital for population health risk assessment and geological point of view and can be evaluated as rate of exhalation and source concentration (226Ra, 232Th and 40K). The present study deals with the soil samples for investigation of radionuclides content and exhalation rates of radon -thoron gas from different sites in northern Haryana, India. Absorbed dose and associated index estimated in the present study are the measures of environmental radioactivity to inhalation dose. Effective doses received by different tissues and organs by considering different occupancy and conditions are also measured. Exhalation rates of radon and thoron are measured with active scintillation monitors based on alpha spectroscopy namely scintillation radon (SRM) and thoron (STM) monitors respectively. Sample height was optimized before measurement of thoron exhalation rate using STM. Average values of radon and thoron exhalation are found 16.6 ± 0.7 mBqkg-1h-1 and 132.1 ± 2.6 mBqm-2s-1 respectively. Also, a simple approach was also adopted, to evaluate the thoron exhalation which accomplished a lot of challenges, the results are compared with the data obtained experimentally. The study is useful in the nationwide mapping of radon and thoron exhalation rates for understanding the environmental radioactivity status.

A Study on the Scattered Dose in Portable Chest Radiography (portable 흉부촬영시 공간산란선량에 관한 연구)

  • Ahn, Bong-Seon;Lee, Hwan-Hyung
    • Journal of radiological science and technology
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    • v.23 no.2
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    • pp.63-67
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    • 2000
  • The purpose of this study is to survey the present status of portable radiography and the result of free space scattered dose rate when taking a radiography at the general hospital or the university hospital in Taejon city. The results were as follows; 1. The number of cases using portable radiography for three years increased to averages 16.2%, 7.7% per year from January 1st in 1996 to December 31st in 1998. 2. The average of distance of adjacent patients was 219.1 cm at the ward. 3. For portable chest radiography, the free space scattered dose rate was 10.5 mSv/hr at 50 cm distance, 1.8 mSv/hr at 100 cm distance, and 0.2 mSv/hr at 200 cm distance. Therefore, in case of portable chest radiography at the ward, the average of distance of adjacent patients is 219.1 cm, so it does not have influence on the adjacent patients. But during the portable radiography, a guardian who is close to the patient, doctor, nurse and radiologic technologists has to set up the shield to prevent from the unnecessary radiation or the distance should be as great as possible from the mobile X-ray equipment.

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General Pharmacology of AG 60, a New Anticancer Drug (새로운 항암제 AG 60의 일반약리작용)

  • 성연희;안희열;김선돈;이선애;조순옥;한영복
    • Biomolecules & Therapeutics
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    • v.5 no.4
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    • pp.412-418
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    • 1997
  • General pharmacological properties of AG 60 (mixture of acriflavine and guanosine (1:1, w/w)), which has anticancer effect, following intramuscular administration were examined in terms of effects on central nervous system, gastrointestinal system, cardiovascular system, respiratory system and autonomic nervous system in mice, rats, guinea-pigs and rabbits. AG 60 at the dose of 15 mgtg had no influences on pentobarbital sleeping time, spontaneous motor activity, chemoshock produced by pentylenetetrazole solution, writhing syndromes induced by 0.8% acetic acid solution, and motor coordination of mice. However, AG 60 at the dose of 7.5 and 15 mg/kg caused significant decrease of normal body temperature 1 and/or 2 h after the administration. No influence on body temperature was observed at 3.75 mg/kg in mice. Gastric secretion of rat and intestinal motility of mice were not influenced by the dose of 15 mg/kg. In terms of autonomic nervous system, AG 60 did not show direct effect and inhibitory or augmentative action of histamine- or acetylcholine-induced contractions at the concentration of 5 mg/L in the isolated ileum of guinea-pig. The administration of 15 mg/kg of AG 60 did not affect mean arterial blood pressure and heart rate in rat. AG 60 (15 mg/kg) given to anesthetized rabbits showed no effect on respiratory rate.

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A STUDY FOR DOSE DISTRIBUTION IN SPENT FUEL STORAGE POOL INDUCED BY NEUTRON AND GAMMA-RAY EMITTED IN SPENT FUELS

  • Sohn, Hee-Dong;Kim, Jong-Kyung
    • Journal of Radiation Protection and Research
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    • v.36 no.4
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    • pp.174-182
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    • 2011
  • With the reactor operation conditions - 4.3 wt% $^{235}U$ initial enrichment, burn-up 55,000 MWd/MTU, average power 34 MW/MTU for three periods burned time for 539.2 days per period and cooling time for 100 hours after shut down, to set up the condition to determine the minimum height (depth) of spent fuel storage pool to shut off the radiation out of the spent fuel storage pool and to store spent fuels safely, the dose rate on the specific position directed to the surface of spent fuel storage pool induced by the neutron and gamma-ray from spent fuels are evaluated. The length of spent fuel is 381 cm, and as the result of evaluation on each position from the top of spent fuel to the surface of spent fuel storage pool, it is difficult for neutrons from spent fuels to pass through the water layer of maximum 219 cm (600 cm from the floor of spent fuel storage pool) and 419 cm (800 cm from the floor of spent fuel storage pool) for gamma-ray. Therefore, neutron and gamma-ray from spent fuels can pass through below 419 cm (800 cm from the floor) water layer directed to the surface of spent fuel storage pool.

Study in vivo metabolism using nuclear medical examination of the dose rate reduction (체내대사를 이용한 핵의학적 검사의 선량률 저감에 관한 연구)

  • Kang, Yong-Gil;Na, Soo-Kyung;Hong, Jin-Woong;Lee, Gui-Won;Kim, Nak-Sang
    • Korean Journal of Digital Imaging in Medicine
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    • v.14 no.2
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    • pp.75-81
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    • 2012
  • The purpose of this study was administered to the body for examination and treatment, high-energy radioactive isotope(F-18, I-131) in vitro discharge experiments. Increasing exposed dose of radiation to health professionals is caused by the increase of PET/CT use and a radioactive isotope. Therefore, the high-energy isotope F-18 and I-131 after administration about using Metabolite excretion was studied. As a results of this study, patients had plenty of fluids for testing and treatment alone administered radiopharmaceuticals can be more than twice as fast excretion induced emissions. Also was able to get a better image space to reduce the dose rate.

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Effect of Hand Massage on Nausea, Vomiting and Anxiety in Childhood with Leukemia on Chemotherapy (백혈병 환아의 항암화학요법시 손마사지가 오심, 구토 및 불안에 미치는 효과)

  • Han Ji-Eun;Moon Young-Im;Park Ho-Ran
    • Child Health Nursing Research
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    • v.11 no.4
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    • pp.456-464
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    • 2005
  • Purpose: To determine the effects of hand massage on nausea and vomiting, and anxiety in children with Iymphocytic leukemia receiving high dose chemotherapy. Method: The children were assigned to an experimental group(15) or a control group(15). All of the children were diagnosed with acute Iymphocytic leukemia and admitted for high dose chemotherapy at C University Medical Center in Seoul. The hand massage was performed for 10 minutes twice a day over three days. To measure the effects of hand massage, the Index of Nausea and Vomiting by Rhodes et al. and the State-Trait Anxiety Inventory for children by Spielberger were used. The level of anxiety was measured by systolic blood pressure, diastolic blood pressure, and pulse rate. Results: The score for nausea and vomiting decreased in the experimental group. State anxiety for the experimental group was significantly more positive than for the control group at the 2nd measurement. There was a significant difference in systolic blood pressure between the two groups. The level of diastolic blood pressure in the two groups decreased significantly over time. Conclusion: Hand massage could be effective in decreasing nausea and vomiting, state anxiety, pulse rate and blood pressure in children with acute leukemia receiving high dose chemotherapy.

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Effect of Renal Failure on Pharmacokinetics of Atenolol in Rabbits (아테놀올의 체내동태에 대한 신장해의 영향)

  • Lee, Chong Ki;Cho, Sam Sang
    • Korean Journal of Clinical Pharmacy
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    • v.8 no.1
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    • pp.23-28
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    • 1998
  • The pharmacokinetics of atenolol (25 mg/kg, i.v.) in the folate-induced renal failure rabbits was studied. Renal failure was induced by the i.v. injection of folate (50, 100, and 200 mg/kg). At folate dose of 100 and 200 mg/kg, the serum creatinine concentration (Scr) and blood urea nitrogen (BUN) increased significantly compared with control rabbits. Plasma concentrations and AUC of atenolol increased significantly at folate dose of 100 and 200 mg/kg. The elimination rate constant $(K_{el})$ and total body clearance $(CL_t)$ of atenolol decreased significantly, and half-life ($t_{1/2}$) and mean residence time (MRT) of atenolol increased significantly at folate dose of 100 and 200 mg/kg. The serum creatinine concentration $(S_{cr})$ correlated well (p<0.05) with half-life $(t_{1/2})$ and elimination rate constant $(K_{el})$ of atenolol, as well as BUN with AUC and total body clearance $(CL_t)$ of atenolol.

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