Open Access. Powered by Scholars. Published by Universities.®
- Discipline
- Keyword
-
- Physical Sciences (4)
- : radiation exposure rate (1)
- Annual absorbed dose (1)
- Annual effective dose equivalent (1)
- Bremsstrahlung Photons (1)
-
- Catphan phantom; Machine Learning (ML); MDCT; Pareto front; RFR model (1)
- ECRIS (1)
- Excessive lifetime cancer risk (1)
- Gamma-Scout (1)
- Geochemical Investigation; Rare Earth Elements (REEs); REE Ratios (La/Ce (1)
- HDR brachytherapy; High-Z nanoparticles; Radio-sensitisation;Dose distribution; Monte Carlo simulation (1)
- NaI(TI) detector (1)
- Natural radioactivity; Marine sediments; Radiological hazards; Lindi coast; HPGe gamma-ray spectrometry; (1)
- Nd/Ce (1)
- RF powers. (1)
- Radial (1)
- Sm/Nd); Uranium Provenance (1)
Articles 1 - 6 of 6
Full-Text Articles in Nuclear
Natural Radioactivity And Radiological Hazards In Sediments From The Lindi Coast, Indian Ocean, Tanzania, Viator Mujuni, Innocent J. Lugendo
Natural Radioactivity And Radiological Hazards In Sediments From The Lindi Coast, Indian Ocean, Tanzania, Viator Mujuni, Innocent J. Lugendo
Tanzania Journal of Science
The Lindi coast of the Indian Ocean, located in southeastern Tanzania, supports rich biodiversity and has recently experienced rapid growth in socio-economic activities such as fishing, mining, and oil and gas exploration. These activities may enhance levels of natural radioactivity in coastal sediments, potentially increasing radiation exposure to local populations. Therefore, monitoring radioactivity levels and estimating associated radiation doses in this region is important. In this study, thirty-six sediment samples were collected from twelve locations along the Lindi coast and analysed for naturally occurring radionuclides using high-purity germanium (HPGe) gamma-ray spectrometry. The activity concentrations of 226Ra, 232Th, and …
Monte Carlo Analysis Of Dose Distribution In Tumour And Adjacent Healthy Tissues During 192Ir Hdr Brachytherapy In The Presence Of Gold Nanoparticles, Damian P. Tippe, Innocent J. Lugendo
Monte Carlo Analysis Of Dose Distribution In Tumour And Adjacent Healthy Tissues During 192Ir Hdr Brachytherapy In The Presence Of Gold Nanoparticles, Damian P. Tippe, Innocent J. Lugendo
Tanzania Journal of Science
High dose rate (HDR) brachytherapy using 192Ir is an effective modality for cancer treatment; however, its therapeutic efficiency is often constrained by unintended radiation exposure to healthy tissues surrounding the tumour. Fortunately, the incorporation of high atomic number (Z) nanoparticles as radiosensitizers has emerged as a promising strategy to enhance tumour dose while sparing adjacent normal tissues. In this study, the dose distribution in tumour and nearby healthy tissues during 192Ir HDR brachytherapy was investigated in the presence of gold (Au) nanoparticles using Monte Carlo simulations based on the Geant4 toolkit. Radial dose distributions and anisotropy characteristics were analysed …
Bremsstrahlung Photons Emissions Measured At Different Rf Power In 28 Ghz Ecr Ion Source, Mwingereza John Kumwenda
Bremsstrahlung Photons Emissions Measured At Different Rf Power In 28 Ghz Ecr Ion Source, Mwingereza John Kumwenda
Tanzania Journal of Engineering and Technology (TJET)
High-performance electron cyclotron resonance ion sources (ECRISs) generate large amounts of bremsstrahlung photons that affect the cryogenic systems due to the extra heat load that is produced. Thus, this study investigates the bremsstrahlung photons energy spectra at various RF powers, presenting some insight about the trends of the electron heating process inside the plasma. Bremsstrahlung photons from a 28 GHz ECRIS were measured at Busan center of Korean Basic Science Institute (KBSI). The gamma-ray detection system consists of three round-type NaI(Tl) scintillation detectors placed 620 mm radially from the beam axis at the extraction side of the ECRIS, and a …
Optimization Of Image Quality Of Simulated Multiple Detectors Computed Tomography Acquisition Parameters Using Machine Learning And Catphan Phantom, Ali O. Masoud, Najat K. Mohammed, Khamis O. Amour, Ahmed M. Jusabani, Denise Mwalongo, Mwingereza John Kumwenda
Optimization Of Image Quality Of Simulated Multiple Detectors Computed Tomography Acquisition Parameters Using Machine Learning And Catphan Phantom, Ali O. Masoud, Najat K. Mohammed, Khamis O. Amour, Ahmed M. Jusabani, Denise Mwalongo, Mwingereza John Kumwenda
Tanzania Journal of Science
The study successfully employed Monte Carlo (MC) simulation and a Machine Learning (ML) approach using a Random Forest Regression (RFR) model to develop optimized Multi-Detector CT (MDCT) protocols that significantly reduce radiation dose while maintaining diagnostic image quality. The MC engine accurately modeled X-ray spectra, and the RFR model demonstrated high predictive power for key metrics, achieving R2 scores of 0.97 for CTDIvol and over 0.92 for image quality metrics (Noise, CNR). Through multi-objective optimization guided by the RFR, the final protocol (Optimization-3) was found on the Pareto front, achieving a notable 35% dose reduction (from 15.5 mGy to 9.9 …
Geochemical Fingerprinting Of Tanzanian Uranium Deposits: The Insights Of Ree Ratios (La/Ce, Nd/Ce, And Sm/Nd) As A Provenance Tool, Lazaro H. Meza, John W. Kondoro, Iyabo T. Usman, Najat K. Mohammed, Titus A. Msagati, Mwingereza John Kumwenda, Mohamed S. Mazunga
Geochemical Fingerprinting Of Tanzanian Uranium Deposits: The Insights Of Ree Ratios (La/Ce, Nd/Ce, And Sm/Nd) As A Provenance Tool, Lazaro H. Meza, John W. Kondoro, Iyabo T. Usman, Najat K. Mohammed, Titus A. Msagati, Mwingereza John Kumwenda, Mohamed S. Mazunga
Tanzania Journal of Science
Accurate uranium provenance determination is crucial for nuclear non-proliferation and environmental protection, yet a forensic-level geochemical framework for Tanzanian uranium deposits has been lacking. This study establishes a robust analytical method using forty-five samples from three major deposits (Mkuju, Manyoni, and Bahi), analyzing elemental compositions, particularly Rare Earth Elements (REEs), via ICP-MS, and validating results using Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA). Despite their proximity, the deposits exhibit distinct geochemical signatures as revealed by key REE ratios and anomalies. Mkuju (mean La/Ce 1.17, Nd/Ce 0.62, Sm/Nd 0.56) is characterized by a positive Europium (Eu) anomaly and heavy …
Assessment Of Radiation Exposure Levels From Selected Scrap Metal Stores In Dar Es Salaam, Tanzania, Innocent J. Lugendo
Assessment Of Radiation Exposure Levels From Selected Scrap Metal Stores In Dar Es Salaam, Tanzania, Innocent J. Lugendo
Journal of Humanities and Social Sciences
This study analyses the radiation exposure rate emanating from scrap metal stores in Dar es Salaam, Tanzania, using the ion chamber based survey meter and a Gamma-Scout radiation detector. Two (2) scrap metal stores located at Manzese and Ubungo-External were selected for the investigation. The radiation exposure rates in μSv/hr at 20 randomly selected points in each store were determined using a survey meter. More readings were taken at points 100m away from each of the stores to establish the background radiation exposure. From the readings of the survey meter, 3 points with the highest radiation exposure rates from each …