World Journal of Nuclear Science and Technology

Journal Information
ISSN / EISSN: 21616795 / 21616809
Total articles ≅ 247

Latest articles in this journal

Sadeem Abdulrahman Alsuhaibani, Khalda T. Osman
World Journal of Nuclear Science and Technology, Volume 12, pp 113-132; https://doi.org/10.4236/wjnst.2022.124010

Abstract:
Based on the statistical model and taking into account the Q-value dependence and odd-even effects, we proposed a new empirical formula to reproduce the cross sections of the (n, p) reactions at 14.7 MeV neutron energy and at the target mass number 14 ≤ A ≤ 198 for even A and 29 ≤ A ≤ 205 for odd A. All calculated results from the proposed empirical formula were compared to the experimental data as well as the available semi-empirical formula obtained by other authors. A high level of agreement has been found between the collected experimental data and the most of semiempirical formulae obtained by others.
Kyeongmo Hwang, Ilsu So, Hyukki Seo
World Journal of Nuclear Science and Technology, Volume 12, pp 101-112; https://doi.org/10.4236/wjnst.2022.123009

Abstract:
It has been known that FAC, LDIE, cavitation and flashing are the damage mechanisms that can cause the pipe thickness of the secondary system of nuclear power plants thinner. Severe wall thinning was found in the MSR drain pipes at a Korean nuclear power plant a decade ago, and all the affected pipes were replaced with low alloy steel with higher chromium contents. Therefore, this study was conducted to reduce the possibility of similar thinning cases that may occur in the future by identifying the exact cause of thinning. ToSPACE and FLUENT codes and theoretical evaluation method were applied to analyze the causes of thinning. ToSPACE and FLUENT analyses and theoretical evaluation including all the operating conditions show a relatively large pressure drop and a pressure lower than the saturated vapor pressure in common at the end of the pipe entering the condenser. This means that flashing occurs at the end of the pipe under all operating conditions, and the effect can be greater than that of other parts. As a result, since severe wall thinning occurred at the end of the pipeline entering the condenser, it was evaluated that flashing by the high-velocity two-phase fluid was the direct cause of the wall thinning in the MSR drain pipes. The results of this study will contribute to establishing appropriate countermeasures in the event of pipe wall thinning in the future.
Rulee Baruah, Kalpana Duorah, Hira Lal Duorah
World Journal of Nuclear Science and Technology, Volume 12, pp 88-100; https://doi.org/10.4236/wjnst.2022.122008

Abstract:
Stellar weak interaction processes play a significant role during the supernova explosion condition after collapse leading to the formation of neutron star. In dynamic events like core-collapse supernovae the high entropy wind scenario arises from considerations of the newly born proto-neutron star. Here, the late neutrinos interact with matter of the outermost neutron star layers leading to moderately neutron rich ejecta. We study the electron capture and beta decay rates of Co and Cd isotopes at various temperature and density conditions in an astrophysical environment and found that the beta decay rates are much higher than the corresponding electron capture rates at all the conditions.
Frederick Agyemang, Stephen Yamoah, Seth Kofi Debrah
World Journal of Nuclear Science and Technology, Volume 12, pp 69-87; https://doi.org/10.4236/wjnst.2022.122007

Abstract:
Effect of pseudocritical rapid energy dissipation (PRED) from Pressurizer in nuclear steam supply system of Pressurized Water Reactor, where a single event as common cause failure, of considerable reduction of base-load electricity demand causes the temperature of the reactor coolant system (RCS) to increase, and corresponding pressure increases in pressurizer and steam generators above set-points. The study employed the uses of MATLAB/Simulink library tools, to experimentally modelled pressure control as PRED, where the momentum of transport of kinematic viscosity fraction above pseudocritical point dissipated as excess energy, to maintain the safety of the Pressurizer and RCS and keep the water from boiling. The result demonstrated the significance of pressure vector and Prandlt number as heat transfer coefficients that provided detailed activities in 2-D contour and 3-D graphics of specific internal energy and other parameterization of fluid in the pressurizer.
Epi Zita Tatiana Kocola Achi, Bogbé Douo Louis Huberson Gogon, Koudou Djagouri, Marie Chantal Kouassi Goffri
World Journal of Nuclear Science and Technology, Volume 12, pp 55-68; https://doi.org/10.4236/wjnst.2022.121006

Abstract:
The radioactive isotopes of the decay series of uranium-238 (238U), thorium-232 (232Th) and potassium-40 (40K) occur naturally in varying amounts in groundwater. They are the subject of many measures, mainly because of the risk they represent from a public health point of view. The purpose of this study is to measure the radioisotope content of borehole waters from the north riviera (NR) catchment field of the Ivorian drinking water distribution company (SODECI). These measurements will make it possible to assess the absolute levels of radioisotopes in the water from SODECI’s boreholes used directly for drinking or swimming, and possibly the associated risk from a public health point of view. To achieve this, a sampling campaign from the seven functional boreholes and the control or treatment tower took place in July 2018 at the NR well field. The analysis of radionuclides by gamma spectrometry was carried out in the laboratory of the Radiation Protection Institute (RPI) of the Ghana Atomic Energy Commission (GAEC). The naturally occurring radionuclides identified during the borehole water samples analysis are 238U, 232Th, and 40K. The results reveal that the specific activities of uranium vary from 0.45 ± 0.18 Bq/L to 0.55 ± 0.17 Bq/L with an average of 0.49 ± 0.15 Bq/L. Those of thorium vary from 0.66 ± 0.14 Bq/L to 0.78 ± 0.18 Bq/L with an average of 0.72 ± 0.16 Bq/L and potassium of 4.14 ± 0.53 Bq/L at 5.87 ± 0.60 Bq/L with an average of 5.32 ± 0.58 Bq/L.
Olkalé Jean-Claude Brigui, Tekpo Paul Amewe Dali, Koudou Djagouri, Bogbé Douo Louis Huberson Gogon, Samafou Penabei, Aka Antonin Koua, Georges Alain Monnehan
World Journal of Nuclear Science and Technology, Volume 12, pp 43-54; https://doi.org/10.4236/wjnst.2022.121005

Abstract:
Sand is an important natural material for the construction of houses, work buildings and other public spaces. This work, which is one of the first contributions to the environmental quality of construction materials, concerns the measurement of natural radioactivity in the lagoon sands collected in the district of Abidjan. Nineteen (19) samples of these sands are analyzed by gamma-ray spectrometry equipped with HPGe detector. The mean values obtained for 226Ra, 232Th and 40K are respectively 7.76 ± 1.84 Bq·kg-1, 5.21 ± 1.36 Bq·kg-1, and 217.31 ± 5.03 Bq·kg-1. The estimated average value of radium equivalent (Raeq) is 31.94 Bq·kg-1. The results show that the average values obtained are far lower than the global limits of 35, 30, and 400 Bq·kg-1 for the concentrations of 226Ra, 232Th and 40K, respectively, and 370 Bq·kg-1 for the equivalent radium established by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). Therefore, the use of the analyzed lagoon sand samples in the different construction sectors should not cause serious radiological effects on the populations living in the District of Abidjan. Our results provide new data on building materials radioactivity in Côte d’Ivoire and all over the World. They can also be used as a reference for future work.
Adji Yaram Diop, Magatte Diagne, Ndeye Arame Boye Faye, Mamadou Moustapha Dieng
World Journal of Nuclear Science and Technology, Volume 12, pp 28-42; https://doi.org/10.4236/wjnst.2022.121004

Abstract:
Diagnostic Reference Levels (DRLs) are indicators that allow assessing the quality of equipment and procedures from the point of view of the doses delivered to patients and subsequently initiate corrective actions if necessary. The purpose of this study is to encourage health professionals to investigate patient radiation doses and to determine whether those doses comply with the principles of radiation protection in medical fields so as to improve practices by reducing patient exposure without reducing clinical effectiveness. To perform this work, we have investigated patient doses for different radiological examinations from six (6) medical centers in Dakar, including the following nine routine types: chest (PA), abdomen (AP), pelvis (AP), cervical spine (AP), lumbar spine (AP, Lat), hip (AP), thoracic spine (AP, Lat). Three types of data were collected, i.e., X-ray tube machine data, patient data and output measurements. The data were analyzed statistically and the median, minimum, maximum, and third quartile values were calculated and displayed throughout boxplots graphs for all exams and medical centers. The two sigma range (95% confidence interval) was also checked. Comparison of third quartiles of Entrance Surface Dose (ESD) and Dose Area Product (DAP) by type of examination with recommended international DRLs was performed. The third quartile of ESD for pelvis (AP) and thoracic spine (AP) was up to 16% and 38% higher, respectively than their corresponding DRLs in the European Commission Report RP 180 Part 2. For all exams, except thoracic spine (lat), the third quartiles of the dose area product were higher than the corresponding DRLs in the above report. The source of dose variability between medical centers was related to many parameters such as poor radiographic techniques, lack of modern X-ray machines and adequately documented radiation protection practices. The results show the need to develop protocols for dose measurement as well as to carry out quality assurance programs and dose optimization in Senegal.
Nguyen Thi Thu Ha, Trinh Van Giap, Bui Duc Ky
World Journal of Nuclear Science and Technology, Volume 12, pp 21-27; https://doi.org/10.4236/wjnst.2022.121003

Abstract:
Lithium aluminate (LiAlO2) powder was synthesized by sol-gel with EDTA method. The resultant powders were characterized by X-Ray Diffraction (XRD) and Scanning Electronic Microscopy (SEM) techniques. In addition, several thermoluminescence properties of synthesized LiAlO2 powder were reported. The results from X-ray diffraction (XRD), the powder prepared by sol-gel with EDTA method showed pure γ-phase when it was calcined at >900°C. Scanning electron microscopy (SEM) results show that the size of the lithium aluminate particles depended strongly on calcination temperature. The linearity is observed of synthesized LiAlO2 powder by sol-gel with EDTA with regression coefficient (R2) is 0.9971.
Balireddy Vasundhara, Pottumuthu Hemalatha, Pakalapati Satya Sarath Kumar Raju
World Journal of Nuclear Science and Technology, Volume 12, pp 11-20; https://doi.org/10.4236/wjnst.2022.121002

Abstract:
Context: Positron emission tomography is a nuclear medicine imaging that deals with physiological function using radioisotopes. With the most PET (Positron Emission Tomography) scanners in integration with the CT scanners of late, this technology has registered phenomenal growth. The small amount of radioactive material is called Radiotracers. Objective: Like 18F- Fluro-deoxy-2-glucose has widely used. In this article, the author introduced clinical applications of PET out of 25 patients who studied hypermetabolic lesions in lymph nodes. Methods: PET imaging is coincidence imaging which is different from the other imaging technique PET image formed from multiple rings of detector crystals. Each decay positron travel in tissue annihilation reaction is going on. FDG is the most commonly used radiotracer to detect and stage various types of malignancies. Result: The field of PET/CT imaging cares for many oncology patients. PET improved localization of malignant lesions. It improved staging biopsy and therapy. Conclusion: Finally, studies to data showed 4% to 10% improvement in the overall accuracy of staging/restaging in lesions. If we use Monte Carlo simulation, OLINDA/EXM software may improve further with widely used.
Kyeong Mo Hwang, Dong Jin Lee, Hun Yun, Seung Chang Yoo, Ji Hyeon Kim
World Journal of Nuclear Science and Technology, Volume 12, pp 1-10; https://doi.org/10.4236/wjnst.2022.121001

Abstract:
Recently, damage caused by liquid droplet impingement erosion (LDIE) in addition to flow-accelerated corrosion (FAC) has frequently occurred in the secondary side steam piping of nuclear power plants, and the damage-occurring frequency is expected to increase as their operating years’ increase. In order to scrutinize its causes, therefore, an experimental study was conducted to understand how the behavior of LDIE-FAC multiple degradation changes when the piping of nuclear power plants is operated for a long time. Experimental results show that more magnetite was formed on the surface of the carbon steel specimen than on the low-alloy steel specimen, and that the rate of magnetite formation and extinction reached equilibrium due to the complex action of liquid droplet impingement erosion and flow-accelerated corrosion after a certain period of time. Furthermore, it was confirmed at the beginning of the experiment that A106 Gr.B specimen has more mass loss than A335 P22 specimen. After a certain period of time, however, the mass loss tends to be the opposite. This is presumed to have resulted from the magnetite formed on the surface playing a role in suppressing liquid droplet impingement erosion. In addition, it was confirmed that the amount of erosion linearly increases under the conditions in which the formation and extinction of magnetite reach equilibrium.
Back to Top Top