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1.
PLoS One ; 19(8): e0308479, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39106296

RESUMO

INTRODUCTION: Radiation exposure in medical settings stands as the primary source of artificial radiation, compounded by the yearly rise in healthcare worker numbers. Ensuring radiation protection is crucial for safeguarding their occupational health. Nevertheless, existing studies on radiation protection behavior exhibit considerable heterogeneity due to various factors. OBJECTIVE: This scoping review aims to explore the current status of research on radiation protection behavior and identify research gaps, intending to guide future research directions. METHODS AND ANALYSIS: The scoping review will follow the Arksey and O'Malley framework and the Joanna Briggs Institute methodology. A systematic search will be conducted across English databases including PubMed, Web of Science, Embase, and Medline, as well as Chinese databases such as CNKI, Wanfang, VIP, and China Biomedical Literature Database. Two independent reviewers will screen the studies based on predefined eligibility criteria and extract the data. Any disagreements will be resolved through discussion by a third reviewer. The review will be reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis extension for Scoping Reviews. STRENGTHS AND LIMITATIONS OF THIS STUDY: A stakeholder consultation will provide an opportunity to validate the findings and address any potential gaps in the article. In this scoping review, all types of studies will be considered. The effectiveness of the methodological quality of the included studies will not be reported, which may lead to some studies of poor quality being included. Only studies published in English or Chinese after 2010 will be considered in this review, potentially leading to the omission of relevant papers.


Assuntos
Pessoal de Saúde , Proteção Radiológica , Humanos , Proteção Radiológica/métodos , Exposição Ocupacional/prevenção & controle , Exposição à Radiação/efeitos adversos , Exposição à Radiação/prevenção & controle
2.
Radiographics ; 44(8): e230197, 2024 08.
Artigo em Inglês | MEDLINE | ID: mdl-39088363

RESUMO

Fluoroscopy is an advanced medical imaging modality that utilizes x-rays to acquire real-time images throughout a medical examination. It is commonly used in various procedures such as in interventional radiology, cardiac catheterization, and gastrointestinal and genitourinary studies. While fluoroscopy is a valuable diagnostic and therapeutic tool, it exposes patients and medical staff to ionizing radiation, which carries health risks. A radiation dose summary page is a report generated by the fluoroscope that displays important information about the procedure. It provides an overview of the radiation doses administered during a fluoroscopic procedure, as well as certain technical parameters used during the irradiation events. The contents of a radiation dose summary page may vary depending on the make and model of the fluoroscope but some common elements include the cumulative reference air kerma, which serves as a surrogate of radiation dose delivered to the patient, and the dose-area product, which takes account of the x-ray beam area and is a measure of the total amount of energy imparted on the patient. Other imaging acquisition parameters may be also included in the dose summary page, including tube voltage, tube current, pulse width, pulse rate, spectral filters, primary and secondary angles, and source-to-image distance. The radiation dose summary page for fluoroscopy is a useful tool for physicians, technologists, and medical physicists, allowing them to comprehend the technical details of a fluoroscopically guided procedure. ©RSNA, 2024.


Assuntos
Doses de Radiação , Radiografia Intervencionista , Fluoroscopia , Humanos , Radiografia Intervencionista/métodos , Proteção Radiológica/métodos
3.
J Radiol Prot ; 44(3)2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39121871

RESUMO

In this study, we devised a radiation protection tool specifically designed for healthcare professionals and students engaged in cardiac catheterization to easily monitor and evaluate scattered radiation distribution across diverse C-arm angles and arbitrary physician associated staff positions-scrub nurse and technologist positions. In this study, scattered radiation distributions in an angiography room were calculated using the Monte Carlo simulation of particle and heavy ion transport code system (PHITS) code. Four visualizations were performed under different C-arm angles with and without radiation protection: (1) a dose profile, (2) a 2D cross-section, (3) a 3D scattered radiation distribution, and (4) a 4D scattered radiation distribution. The simulation results detailing the scattered radiation distribution in PHITS were exported in Visualization Toolkit format and visualized through the open-source visualization application ParaView for analysis. Visualization of the scattered dose showed that dose distribution depends on the C-arm angle and the x-ray machine output parameters (kV, mAs s-1, beam filtration) which depend upon beam angulation to the patient body. When irradiating in the posterior-anterior direction, the protective curtain decreased the dose by 62% at a point 80 cm from the floor, where the physician's gonads are positioned. Placing the protection board close to the x-ray tube reduced the dose by 24% at a location 160 cm from the floor, where the lens of the eye is situated. Notably, positioning the protection board adjacent to the physician resulted in a 95.4% reduction in incident air kerma. These visualization displays can be combined to understand the spread and direction of the scattered radiation distribution and to determine where and how to operate and place radiation protection devices, accounting for the different beam angulations encountered in interventional cases. This study showed that scatter visualization could be a radiation protection teaching aid for students and medical staff in angiography rooms.


Assuntos
Método de Monte Carlo , Exposição Ocupacional , Doses de Radiação , Proteção Radiológica , Espalhamento de Radiação , Humanos , Proteção Radiológica/métodos , Exposição Ocupacional/prevenção & controle , Exposição Ocupacional/análise , Angiografia Coronária
4.
Health Phys ; 127(4): 504-512, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39190883

RESUMO

The maturation of robotic and remote systems presents opportunities to expand the use of technologies that have typically been restricted to high-dose/high-risk nuclear work for moderate- or low-risk work to further reduce radiation exposure to workers. This study quantifies the potential dose savings achieved through the use of robotic techniques for characterizing transuranic-contaminated waste items and compares dose estimates from a simplistic, user-friendly deterministic radiation transport code and a more robust, complex Monte Carlo code. Three scenarios of transuranic-contaminated waste items described in published reports are modeled using representative source geometries in MicroShield and MCNP radiation transport codes. Estimated dose rates are determined at points ranging from 30 cm to 300 cm from the face of the waste item to represent the increase in distance allowed by robotic or remote system implementation for characterization activities. The dose rate savings are then converted to detriment cost savings using a dollar-per-person-dose conversion factor to provide a financial context. The radiation transport simulations show no consistent bias in estimated dose rate by varying simulation methodology or using geometrical simplifications-in some cases, MicroShield produces higher dose rate estimates while MCNP estimates are higher in other cases. In the MCNP simulations, the volume source geometry consistently produces a higher dose rate than the slab source geometry, but the MicroShield dose rate estimates do not display the same trend. Dose savings range from 1.60 × 10-5 µSv h-1 to 1.75 × 101 µSv h-1 with associated detriment cost savings from < 0.010 USD/person-h to 14 USD/person-h.


Assuntos
Método de Monte Carlo , Doses de Radiação , Monitoramento de Radiação/métodos , Humanos , Resíduos Radioativos/análise , Simulação por Computador , Proteção Radiológica/métodos , Robótica , Exposição Ocupacional/análise
5.
Rev Med Suisse ; 20(883): 1418-1421, 2024 Aug 21.
Artigo em Francês | MEDLINE | ID: mdl-39175292

RESUMO

Incidents involving ionizing radiation pose a risk of immediate and long-term clinical consequences for both victims and responders in the event of secondary contamination. Rapid identification of the problem and a coordinated response are crucial. This article summarizes the key challenges related to the emergency management of a single patient or multiple victims, addressing the importance of recognizing such a case, radioprotection measures, decontamination, and available treatments.


Les incidents impliquant des rayonnements ionisants représentent un risque aux conséquences cliniques immédiates et à long terme, tant pour les victimes que pour les intervenants en cas de contamination secondaire. L'identification rapide de la problématique et une réponse coordonnée sont cruciales. Cet article résume les principaux enjeux liés à la prise en charge en urgence d'un patient unique ou de plusieurs victimes, en abordant l'importance de la reconnaissance d'un tel cas, des mesures de radioprotection, de la décontamination et des traitements disponibles.


Assuntos
Lesões por Radiação , Liberação Nociva de Radioativos , Humanos , Lesões por Radiação/diagnóstico , Lesões por Radiação/terapia , Lesões por Radiação/etiologia , Lesões por Radiação/prevenção & controle , Serviços Médicos de Emergência/métodos , Descontaminação/métodos , Proteção Radiológica/métodos
6.
Biomed Phys Eng Express ; 10(5)2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39094590

RESUMO

Purpose. Secondary skin collimation (SSC) is essential for shielding normal tissues near tumors during electron and orthovoltage radiation treatments. Traditional SSC fabrication methods, such as crafting in-house lead sheets, are labor-intensive and produce SSCs with low geometric accuracy. This study introduces a workflow that integrated 3D scanning and 3D printing technologies with an in-house mold process, enabling the production of patient-specific SSCs within six hours.Methods. An anthropomorphic head phantom was scanned with a handheld 3D scanner. The resulting scan data was imported into 3D modeling software for design. The completed model was exported to a 3D printer as a printable file. Subsequently, molten Cerrobend was poured into the mold and allowed to set, completing the SSC production. Geometric accuracy was assessed using CT images, and the shielding effectiveness was evaluated through film dosimetry.Results. The 3D printed mold achieved submillimeter accuracy (0.5 mm) and exhibited high conformity to the phantom surface. It successfully endured the weight and heat of the Cerrobend during pouring and curing. Dosimetric analysis conducted with radiochromic film demonstrated good agreement between the measured and expected attenuation values of the SSC slab, within ±3%.Conclusions. This study presents a proof of concept for novel mold room workflows that produce patient-specific SSCs within six hours, a significant improvement over the traditional SSC fabrication process, which takes 2-3 days. The submillimeter accuracy and versatility of 3D scanning and printing technologies afford greater design freedom and enhanced delivery accuracy for cases involving irregular geometries.


Assuntos
Imagens de Fantasmas , Impressão Tridimensional , Pele , Humanos , Tomografia Computadorizada por Raios X/métodos , Software , Cabeça , Desenho de Equipamento , Proteção Radiológica/métodos , Proteção Radiológica/instrumentação , Dosimetria Fotográfica/métodos , Dosimetria Fotográfica/instrumentação
7.
Radiat Prot Dosimetry ; 200(13): 1251-1257, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-38949111

RESUMO

A De-Pangher-type long counter was designed for neutron measurements in standard neutron fields based on the results of simulations using the MCNP6 code at the National Metrology Institute of Japan, the National Institute of Advanced Industrial Science and Technology. The effects of six parameters in the design on the energy response of the long counter were investigated. The energy response was then quantitatively evaluated for eight design candidates selected from the investigation. The calculation results show that these candidates have a flatter energy response from 100 eV to 10 MeV compared to that of the current long counter. These candidates also reduce the difference between the average energy response from 10 eV to 1 MeV and that from 10 to 20 MeV.


Assuntos
Simulação por Computador , Desenho de Equipamento , Método de Monte Carlo , Nêutrons , Doses de Radiação , Japão , Proteção Radiológica/métodos , Monitoramento de Radiação/métodos , Humanos , Radiometria/métodos
8.
Radiat Prot Dosimetry ; 200(13): 1266-1273, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-38992985

RESUMO

This study examines the relationship between ambient dose H*, ambient dose equivalent H*(10), and effective dose E for external neutron irradiation over 163 operational spectra from different workplaces. The results show that H* provides a reasonable estimate with a controlled margin, even if overestimated, to assess E compared with H*(10), which can lead to a significant overestimation or underestimation of E depending on the neutron spectra. The results highlight the limitations of H*(10) and the superiority of H* in estimating E according to the requirements of the operational quantities, especially in environments with high-energy neutrons.


Assuntos
Nêutrons , Exposição Ocupacional , Doses de Radiação , Monitoramento de Radiação , Monitoramento de Radiação/métodos , Exposição Ocupacional/análise , Humanos , Proteção Radiológica/métodos
9.
Life Sci Space Res (Amst) ; 42: 133-139, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39067984

RESUMO

Astronauts participating in lunar landing missions will encounter exposure to albedo particles emitted from the lunar surface as well as primary high-energy particles in the spectra of galactic cosmic rays (GCRs) and solar particle events (SPEs). While existing studies have examined particle energy spectra and absorbed doses in limited radiation exposure scenarios on and near the Moon, comprehensive research encompassing various shielding amounts and large SPEs on the lunar surface remains lacking. Additionally, detailed organ dose equivalents of albedo particles in a human model on the lunar surface have yet to be investigated. This work assesses the organ dose equivalents of albedo neutrons and albedo protons during historically large SPEs in August 1972 and September 1989 utilizing realistic computational anthropomorphic human phantom for the first time. Dosimetric quantities within human organs have been evaluated based on the PHITS Monte Carlo simulation results and quality factors of the state-of-the-art NASA Space Cancer Risk (NSCR) model, as well as ICRP publications. The results with the NSCR model indicate that the albedo contribution to organ dose equivalent is less than 3 % for 1 g/cm2 aluminum shielding, while it increases to more than 30 % in some organs for 50 g/cm2 aluminum shielding during exposure to low-energy-proton-rich SPEs.


Assuntos
Radiação Cósmica , Método de Monte Carlo , Lua , Nêutrons , Prótons , Doses de Radiação , Voo Espacial , Humanos , Radiação Cósmica/efeitos adversos , Nêutrons/efeitos adversos , Prótons/efeitos adversos , Astronautas , Atividade Solar , Proteção Radiológica/métodos , Imagens de Fantasmas , Exposição à Radiação/análise
10.
Environ Geochem Health ; 46(9): 337, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39073619

RESUMO

The first verification of a tool developed to improve the work of controlling bodies, managers and employees of underground facilities subject to radiation protection requirements was conducted. The recommended values of correction factors were verified using archival results of measurements conducted for the Institute of Occupational Medicine in Lódz in seven underground workplaces in Poland over exposure periods of a month (10,8678 data) and a quarter of a year (53,688 data). In a cave two groups of monthly factors, produced estimates with almost 70% to 99% consistency with the measured values. Along tourist routes located in mines, a similar fit was obtained using three groups of correction factors for measurement results from March, June and July. In the extraction areas of active underground mines, the best fit was produced by factors calculated as averages for spaces varying in the degree of insulation and ventilation method, while in other departments of mining plants, by correction factors recommended for facilities equipped with mechanical ventilation systems. All the quarterly correction factors produced the best fit between estimated mean annual concentrations and measurement results obtained in the second quarter of the calendar year. A wide variation in result consistency (from 20-30 to 65-80%) obtained for two underground tourist routes in the fourth quarter of the year demonstrates that it is best not to adopt results from this measurement period (October-December) for estimating mean annual radon concentration using the set of quarterly correction factors.


Assuntos
Poluentes Radioativos do Ar , Exposição Ocupacional , Monitoramento de Radiação , Radônio , Radônio/análise , Polônia , Monitoramento de Radiação/métodos , Exposição Ocupacional/análise , Poluentes Radioativos do Ar/análise , Mineração , Humanos , Proteção Radiológica/métodos , Local de Trabalho
11.
Biomed Pharmacother ; 177: 117029, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38991305

RESUMO

Amifostine (AMF) as the first-line radiation protection drug, usually suffered from low compliance and short half-life upon clinical applications. The development of oral drug delivery system (DDS) for AMF is a promising solution. However, the inherent shortages of AMF present significant challenges in the design of suitable oral DDS. Here in this study, we utilized the ability of calcium ions to bind with AMF and prepared AMF loaded calcium carbonate (CC) core, CC/AMF, using phase transferred coprecipitation method. We further modified the CC/AMF using phospholipids to prepare AMF loaded lipid-calcium carbonate (LCC) hybrid nanoparticles (LCC/AMF) via a thin-film dispersion method. LCC/AMF combines the oral advantages of lipid nanoparticles with the drug-loading capabilities of CC, which was shown as uniform nano-sized formulation with decent stability in aqueous solution. With favorable intestinal transport and absorption effects, it effectively enhances the in vivo radiation protection efficacy of AMF through oral administration. More importantly, we further investigated the cellular accumulation profile and intracellular transport mechanism of LCC/AMF using MDCK and Caco-2 cell lines as models. This research not only alters the current administration method of AMF to enhance its convenience and compliance, but also provides insights and guidance for the development of more suitable oral DDS for AMF in the future.


Assuntos
Amifostina , Carbonato de Cálcio , Nanopartículas , Protetores contra Radiação , Carbonato de Cálcio/química , Administração Oral , Animais , Humanos , Células CACO-2 , Protetores contra Radiação/administração & dosagem , Protetores contra Radiação/química , Protetores contra Radiação/farmacologia , Protetores contra Radiação/farmacocinética , Nanopartículas/química , Amifostina/administração & dosagem , Amifostina/farmacologia , Cães , Lipídeos/química , Células Madin Darby de Rim Canino , Sistemas de Liberação de Medicamentos/métodos , Proteção Radiológica/métodos , Portadores de Fármacos/química
12.
Radiat Prot Dosimetry ; 200(11-12): 983-988, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016472

RESUMO

The present study attempts to obtain an a priori estimate of the absorbed dose received by an individual engaged in the reconnaissance survey in Uranium exploration using a predictive mathematical regression analysis. Other radiation safety parameters such as excess lifetime cancer risk are also calculated. Study reflects that the proper handling of naturally occurring radioactive materials accounts for an absorbed dose significantly less than the prescribed limit.


Assuntos
Exposição Ocupacional , Monitoramento de Radiação , Urânio , Urânio/análise , Humanos , Índia , Monitoramento de Radiação/métodos , Exposição Ocupacional/análise , Doses de Radiação , Proteção Radiológica/métodos , Medição de Risco/métodos , Exposição à Radiação/análise , Neoplasias Induzidas por Radiação/prevenção & controle , Neoplasias Induzidas por Radiação/etiologia , Neoplasias Induzidas por Radiação/epidemiologia
13.
Radiat Prot Dosimetry ; 200(11-12): 1178-1182, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016485

RESUMO

Polydimethyl silicone rubber-based polymer composites filled with molybdenum and bismuth were fabricated using simple open mold cast technique. The physical and chemical structure and gamma shielding parameters like attenuation coefficient, half-value layer (HVL) thickness and relaxation length have been investigated for the said novel materials using X-ray diffraction (XRD), Fourier transform Infrared spectroscopy (FTIR) and gamma ray spectrometer. XRD study reveals the crystalline nature of the composites. It is evident from FTIR studies that there is no chemical interaction between the polymer matrix and filler particles. The results of attenuation studies reveal that the linear attenuation coefficient increases with addition of Bi and Mo and is found to be 0.653, 1.341 and 1.017, 1.793 and 0.102, 0.152 cm-1 for 1MMB and 2MMB polymer composites at 80, 356 and 662 keV gamma rays, respectively. The HVL thickness of the materials is found to be 1.06, 0.51 and 0.68, 0.38 and 6.73, 4.532 cm for 1MMB (20Mo + 10Bi phr) and 2MMB (40Mo + 20Bi phr) at these energies, respectively. The mass attenuation coefficient of the novel composites 1MMB and 2MMB is found to be higher than the conventional materials like lead and barite for 356 keV gamma rays. In addition, the material is found to be light weight and flexible enabling to be molded in required forms, thus being a substitute for the material lead that is known to be heavy and toxic by nature.


Assuntos
Bismuto , Molibdênio , Polímeros , Polímeros/química , Molibdênio/química , Molibdênio/efeitos da radiação , Bismuto/química , Raios gama , Radiação Ionizante , Proteção Radiológica/métodos , Proteção Radiológica/instrumentação , Teste de Materiais , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Humanos
14.
Radiat Prot Dosimetry ; 200(11-12): 1153-1157, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016490

RESUMO

To shield people from dangerous gamma radiation, it is imperative to fabricate inexpensive and environmentally friendly materials. In the present work, suitability of concrete with various % concentrations of ceramics as gamma-ray shielding material has been studied. In this regard, concrete mixture using M-sand and cement with ceramic as filler in different concentrations has been prepared. The mass attenuation coefficients of the prepared samples were measured for different concentrations of ceramics such as 15, 30, 45 and 60%. The mass attenuation coefficients, half value layer (HVL) and tenth vale layer (TVL) of the prepared samples were determined using gamma-ray spectrometer with NaI(Tl) detector at 511, 661.6, 1173, 1332 keV gamma energies. Experimentally obtained mass attenuation coefficients varied from 0.080 to 0.090, 0.074 to 0.086, 0.056 to 0.072 and 0.054 to 0.055 cm2 g-1 at 511, 662, 1173 and 1332 keV, respectively. Therefore concrete mixture with ceramics filler could be a promising shielding material than the bare concrete.


Assuntos
Cerâmica , Materiais de Construção , Raios gama , Proteção Radiológica , Cerâmica/química , Materiais de Construção/análise , Proteção Radiológica/instrumentação , Proteção Radiológica/métodos , Espectrometria gama , Teste de Materiais , Doses de Radiação , Humanos
15.
Radiat Prot Dosimetry ; 200(11-12): 1132-1137, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016493

RESUMO

KAlpakkam MINI reactor (KAMINI) is a 233U fuelled research reactor has various neutron irradiation locations for experimental purposes. The pit at the south beam end of KAMINI reactor is being extensively utilised for neutron attenuation experiments in prospective shielding materials as well as for neutron radiography. During reactor operation, it will be closed by a movable shield. A vault door is located above the shield and the movable shield is used to attenuate streaming neutrons and gamma-rays during reactor operation. Even with the shield, there exists significant dose because of streaming neutrons and gamma rays. Its variation depends on the power of the reactor. The neutron and gamma dose rates close to the south beam vault door have recently been found to be 275-300 µSv/h and 175-200 µSv/h, respectively, when the reactor is operating at 10 kW. In order to characterise the streaming neutron spectra of vault door place for the first time, measurements are done using the Nested Neutron Spectrometer. Along with the neutron flux, neutron mean energy and ambient dose-equivalent rate are also measured and compared with earlier measurements carried out inside the south beam pit. It is observed that the presence of paraffin shield reduces the neutron average energy from 370 to 178 keV. Apart from energy reduction, 10 kW normalised neutron flux of south beam pit is also attenuated by the shield by 25 000 times and it is found that the neutron spectrum of the measured location is also more thermalized. Neutron reference data of the location are generated.


Assuntos
Raios gama , Nêutrons , Reatores Nucleares , Doses de Radiação , Proteção Radiológica , Proteção Radiológica/métodos , Proteção Radiológica/instrumentação , Monitoramento de Radiação/métodos , Monitoramento de Radiação/instrumentação , Desenho de Equipamento , Análise Espectral/instrumentação , Análise Espectral/métodos , Humanos , Tório/análise , Urânio
16.
Radiat Prot Dosimetry ; 200(11-12): 1233-1236, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016503

RESUMO

The shielding of gamma radiation is of the utmost importance in industries, such as nuclear power plants, medical imaging, and space exploration. For the purpose of shielding objects in such an environment, it is essential to design materials with flexibility as well as high shielding capability. In order to enhance the radiation attenuation effectiveness of polymers, such as polyvinyl alcohol (PVA), glass has been blended with varying percentages. The fabricated composite has been subjected to gamma-ray interaction studies. The radiation shielding parameter, such as mass attenuation coefficient (µ/ρ), has been determined for various energies, such as 137Cs (661.6 keV) and 60Co (1173 and 1332 keV). It is observed that the PVA composite with glass exhibits improved gamma radiation shielding properties compared to PVA. Therefore, the present work paves the way for the utility of PVA polymer with glass, offering a cost-effective and sustainable approach to gamma radiation shielding in radiation environments.


Assuntos
Raios gama , Vidro , Álcool de Polivinil , Proteção Radiológica , Vidro/química , Proteção Radiológica/instrumentação , Proteção Radiológica/métodos , Álcool de Polivinil/química , Álcool de Polivinil/efeitos da radiação , Polímeros/química , Radioisótopos de Césio , Radioisótopos de Cobalto , Doses de Radiação , Teste de Materiais
17.
Radiat Prot Dosimetry ; 200(11-12): 1224-1227, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016508

RESUMO

In the present work, the efficacy of waste glass as fillers in concrete for gamma-ray shielding has been studied. Glass fillers of 0, 15, 30, 45, and 60% concentrations have been incorporated into the concrete mixture. The attenuation measurements were performed using gamma spectrometer with NaI(Tl) detector at 511, 662, 1173, and 1332 keV gamma energies. Gamma-ray shielding parameters, such as the mass attenuation coefficient (µ/ρ), are determined for all filler concentrations. The mass attenuation coefficient of the prepared samples was found to be varied from 0.081 to 0.088, 0.071 to 0.088, 0.05 to 0.058, and 0.05 to 0.055 (cm2 per g) for 511, 662, 1173, and 1332 keV gamma energies, respectively. It was observed that experimentally determined (µ/ρ) values were in very good agreement with theoretical values calculated from EDAX data. Furthermore, it was observed that (µ/ρ) showed an increasing trend with an increase in filler concentration, which is attributed to the increase in the shielding property of the material. Therefore, the glass-concrete composite can be accustomed to reduce the intensity of gamma radiation.


Assuntos
Materiais de Construção , Raios gama , Vidro , Materiais de Construção/análise , Vidro/química , Proteção Radiológica/métodos , Espectrometria gama , Teste de Materiais , Doses de Radiação
18.
Radiat Prot Dosimetry ; 200(11-12): 1143-1152, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016510

RESUMO

Electromagnetic shielding parameters are crucial to investigate unexplored nanoparticles and their nanocomposites. Herein, calcium-iron-aluminium (Ca: Fe: Al) nanocomposites are synthesised using the simple solution combustion technique. The as-synthesised nanocomposites with various doping concentrations of Al nanoparticles are characterised to study the structural and surface parameters and to confirm the successful formation. Further, the procured Ca: Fe: Al nanocomposites along with various doping concentrations are utilised for electromagnetic shielding applications, and various shielding parameters are calculated. It was confirmed that Ca: Fe: Al nanocomposites are suitable for electromagnetic shielding applications.


Assuntos
Alumínio , Cálcio , Ferro , Nanocompostos , Proteção Radiológica , Ferro/química , Alumínio/química , Nanocompostos/química , Nanocompostos/efeitos da radiação , Cálcio/química , Proteção Radiológica/métodos , Humanos , Campos Eletromagnéticos , Radiação Eletromagnética
19.
Radiat Prot Dosimetry ; 200(11-12): 1207-1215, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016515

RESUMO

In the present study, we have prepared six glass samples of bismuth borate using the melt-quenching method with the composition (70-x)B2O3-10CaO-20Na2O-xBi2O3; x = 0, 3, 6, 9, 12 and 15 mol%. The density of the prepared glasses was determined using Archimedes principle. The X-ray diffraction patterns provide confirmation of the amorphous nature of the prepared samples, whereas the Fourier transform infrared measurements pointed to the existence of structural units like BO3, BO4, BiO3 and BiO6 within the glass network. An assessment of the optical absorption spectra unveiled that with the increase in the bismuth oxide content, there was a decrease observed in both the direct and indirect band gap energies. Specifically, they decreased from 3.40 to 2.79 eV and from 3.10 to 2.46 eV, respectively. The properties related to gamma ray attenuation, including the mass attenuation coefficient (µm), effective atomic number (Zeff), half-value layer (HVL) and mean free path (MFP), were examined for all the glass samples. This investigation was carried out using the Phy-X/PSD software, covering the energy range from 0.511 to 1.332 MeV. Out of all the samples, Bi-15, featuring the highest Bi2O3 content, demonstrated the highest µm, Zeff, the smallest HVL and MFP. These results suggest that the glass with 15 mol% of Bi2O3 offers the most effective gamma radiation shielding performance. Moreover, the glasses examined in this study exhibit superior radiation shielding characteristics compared with specific concrete types, namely, ordinary concrete, Hematite serpentine concrete and barite concrete, as well as commercial glasses such as RS-360 and RS-253.


Assuntos
Bismuto , Boratos , Raios gama , Vidro , Proteção Radiológica , Bismuto/química , Vidro/química , Boratos/química , Proteção Radiológica/métodos , Cálcio/química , Sódio/química , Difração de Raios X , Teste de Materiais , Espectroscopia de Infravermelho com Transformada de Fourier
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