• Nuclear Engineering and Technology
• /
• v.53 no.5
• /
• pp.1519-1523
• /
• 2021

Radioactive iodine (¹³¹I) released from nuclear power plants has been a critical environmental concern for workers. The effective trapping of radioactive iodine isotopes from the off-gas stream generated from nuclear facilities is an important issue in radioactive waste treatment systems evaluation. Numerous studies on retaining methyl iodide (CH₃I¹³¹) by impregnated activated carbons under the high content of moisture have been extensively studied so far. But there have been no good results on how to remove methyl iodide at high humid conditions up to now. A new challenge is to introduce other promising impregnating chemical agents that are able to uptake enough radioactive methyl iodide under high humid conditions. In order to develop a good removal efficiency to control radioiodine gas generated from a high humid process, activated carbons (ACs) impregnated with triethylene diamine (TEDA) and qinuclidine (QUID) were prepared. In addition, the removal efficiencies of the activated carbons (ACs) under humid conditions up to 95% RH were evaluated by applying the standard method specified in ASTM-D3808. Quinuclidine impregnated activated carbon showed a much higher decontamination factor above 1,000, which is enough to meet the regulation index for the iodine filters in nuclear power plants (NPPs).

• The Korean Journal of Physiology and Pharmacology
• /
• v.19 no.2
• /
• pp.131-139
• /
• 2015

This study analyzed the differences in aerobic and anaerobic exercise ability and growth-related indicators, depending on the polymorphism of the ACE and the ACTN3 genes, to understand the genetic influence of exercise ability in the growth process of children. The subjects of the study consisted of elementary school students (n=856, age $10.32{\pm}0.07yr$). The anthropometric parameters, physical fitness and growth factors were compared among groups of the ACE I/D or the ACTN3 R577X polymorphisms. There were no significant differences between the anthropometric parameters, physical fitness and growth factors for the ACE gene ID or the ACTN3 gene R577X polymorphism. However, the DD type of ACE gene was highest in the side step test (p<0.05), and the DD type was significantly higher than the II+ID type (p<0.05) in the early bone age. The combined group of the ACE gene II+ID and the ACTN3 gene XX type significantly showed lower early bone age (p< 0.05). This study did not find any individual or compounding effects of the polymorphism in the ACE I/D or the ACTN3 R577X polymorphisms on the anthropometric parameters, physical fitness and growth factors of Korean children. However, the exercise experience and the DD type of the ACE gene may affect the early maturity of the bones.

• Journal of Radiation Protection and Research
• /
• v.11 no.2
• /
• pp.139-145
• /
• 1986

An improved mothod of assessing fuel status by analyzsis of the fission product in the reactor coolant system is proposed. The release mechanism of specific fission products is established for determination of the coefficients in the equations which relate the radioactivities with the amount of defected fuel. Knock-out and migration models are employed in the formulation of the release mechanism. The influence of the tramp uranium is quantified. Sample calculations were made for KNU 1 reactor system using the I-131 and I-133 concentrations in the primary coolant. The estimated number of defected fuel pins in the third and sixth cycles appeared to be $9.34{\pm}1.13\;and\;0.294{\pm}0.092$, respectively.

• Journal of Radiation Protection and Research
• /
• v.13 no.2
• /
• pp.41-51
• /
• 1988

In order to develop a food-chain computer code suitable to the environmental conditions of Korea, the FOOD III code was partially modified. The excution results for Korean male-adult were compared to those from the Canadian version of FOOD III to deduce a more realistic approach in dose assessment. The amounts of Mn-54, Co-58, Co-60, I-131 and I-132 released from Kori unit 1 in1984 were used as the source terms for the sample calculation. The maximum atmospheric dispersion factor(X/Q) value on the site boundary was applied. Through the code modification, organ doses decreased by about $20{\sim}70%$ and the effective committed dose equivalent by about 40% to be $7.935{\times}10^{-6}Sv/y$ which is 0.16% of the ICRP limit, $5{\times}10^{-3}Sv/y$.

• The Korean Journal of Nuclear Medicine
• /
• v.4 no.1
• /
• pp.51-60
• /
• 1970

In 1969 this laboratory had prepared 131 mc. of radiopharmaceuticals in total (Hippuran and other four kinds) and distributed to the major medical establishments. The quality and stability of these products were reviewed by means of radio paper partition chromatography and thin layer chromatography and results were compared to those of foreign products. Generally, the quality and stability of the product of this laboratory were better than those of the foreign product, even though the properties of the radiopharmaceutical were varied by the procedure of the preparation adopted. Various precautions for handling radiopharmaceuticals for clinical use were also described with a view of quality control and stability test there of.

• Nuclear Engineering and Technology
• /
• v.55 no.1
• /
• pp.304-309
• /
• 2023

In the last decade, nuclear medicine appears to be a good choice of medicine. ⁵⁸Co, ⁹⁹Mo, ⁹⁹Tc, ⁹⁹Re, ¹³³Xe and ¹⁸⁶Re are very important radionuclides for nuclear medicine. In this study, the excitation functions of ⁵⁸Ni (n, p) ⁵⁸Co, ⁹⁹Tc (n, p) ⁹⁹Mo, ⁹⁹Ru (n, p) ⁹⁹Tc, ¹³¹Xe (n, p) ¹³¹I, ¹³³Cs (n, p) ¹³³Xe and ¹⁸⁶Os (n, p) ¹⁸⁶Re nuclear reactions were calculated at neutron energies between 1 and 20 MeV using TALYS 1.95 and EMPIRE 3.2 nuclear codes. Furthermore, the cross sections were calculated with the empirical formula derived in our past study at 14-15 MeV. The obtained results were compared with the measured values in EXFOR library, and with the evaluated data of (JENDL-4.0/HE, JEFF-3.3, TENDL-2019, ENDF/B-VIII.0, IRDFF-II, JENDL/ImPACT-18). The results are in good agreement with those of the evaluated data libraries and experimental results and indicates that these radioisotopes can be produced by smaller cyclotrons.

• The Journal of the Korean bone and joint tumor society
• /
• v.12 no.2
• /
• pp.131-135
• /
• 2006

Chondrosarcoma can be divided into grade I, II and III by histological finding and a relationship between the prognosis and the histological grading has been identified. Although the surgical treatment of grade II and III chondrosarcoma necessitates wide resection margin, there has been controversy about curettage versus wide resection in case of grade I chondrosarcoma. The authors report a case of grade I chondrosarcoma of proximal humerus and grade II chondrosarcoma of distal humerus with good oncological and functional result through curettage and wide resection respectively.

• Journal of radiological science and technology
• /
• v.31 no.1
• /
• pp.11-16
• /
• 2008

Purpose : The aim of this study was to predict radiation dose at 1 meter with BMI(body mass index) in thyroid cancer patients treated with radio-iodine and provide the efficient guideline in the management of patients. Methods : 140 patients from thyroidectomy for thyroid cancer were enrolled. All subjects under went 150 mCi radio-iodine therapy and performed whole body scan 1 week later. BMI(weight divided by square of height) was calculated to evaluate the amount of fatty tissue indirectly. The radiation dose at 1 meter was measured initially and on 2nd days. the relation of values with BMI were analyzed statically. As for the method of statistical analysis, using Med calc Version 9,2,2,0 Program. Results : (1) The initial effective dose was inversely correlated with the BMI. Significance level was 0.0004. (2) We obtained the following formula from the data of initial effective dose and BMI: Y = -30.91X + 350.4(${\mu}Sv/h$)(Y: initial radiation dose, x: Group). (3) After 21.55 hours, than radiation dose was less than those recommended by ICRP or NRC in 53% of the population. Conclusion : Using BMI, the initial radiation dose and 2nd days dose can be predicted in thyroid cancer patients before radio-iodine therapy. It may be used for predicting the time of discharge and control the isolation room. We were able to predict the radiation exposure after discharge using this calculated value.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.17 no.2
• /
• pp.53-58
• /
• 2013

Purpose: To optimize correction method for SPECT/CT, image quality consisting of resolution and contrast was evaluated using three radioisotopes ($^{99m}Tc$, $^{201}Tl$ and $^{131}I$) and three different correction methods; attenuation correction (AC), scatter correction (SC) and both attenuation and scatter correction (ACSC). Materials and Methods: Images were acquired with a SPECT/CT scanner and a conventional CT protocol with an OESM reconstruction algorithm (2 iterations and 10 subsets). For resolution measurement, fixed radioactivity (2.22 kBq) was infused into a spatial resolution phantom and full width at half maximum (FWHM) was measured using a vendor-provided software. For contrast evaluation, radioactive source with a ratio of 1:8 to background was filled in a Flanged Jaszczak phantom and percent contrast (%) were calculated. All the parameters for image quality were compared with non-correction (NC) method. Results: As compared with NC, image resolution of all three isotopes were significantly improved by AC and ACSC, not by SC. In particular, ACSC showed better resolution than AC alone for $^{99m}Tc$ and $^{201}Tl$. Image contrast of all three radioisotopes in a sphere with the largest diameter were enhanced by all correction methods. ACSC showed the highest contrast in all three radioisotopes, which was the most accurate in $^{99m}Tc$ (85.9%). Conclusion: Image quality of SPECT/CT was improved in all the radioisotopes by CT-based attenuation correction methods, except SC alone. SC failed to improve resolution in any radioisotopes, but it was effective in contrast enhancement. ACSC would be the best correction method as it improved resolution in radioisotopes with low energy levels and contrast in radioisotope with low energy levels. However, in radioisotope with high energy level, AC would be better than ACSC for resolution improvement.

• Proceedings of the KIEE Conference
• /
• 2001.07a
• /
• pp.131-133
• /
• 2001

The basic function of a Power-System Stabilizer(PSS) is to add damping to the generator rotor oscillations by controlling its excitation using auxiliary stabilizing signals. To provide damping. the stabilizer must produce a component of electrical torque in phase with the rotor speed deviations. This paper introduces the hardware specifications and various functions of microprocessor (TMS320C32)-based digital PSS to provide the damping torque.