Radiological Characterization Research Articles

A highly scalable and autonomous spectroscopic radiation mapping system with resilient IoT detector units for dosimetry, safety and security

Technologies utilizing radiological materials across power generation, defence, industry, research and medicine have increased the global inventory of highly active and hazardous materials. Consequently, an amplified threat exists of illicitly obtained materials being used as part of hostile acts. The potential for intentional releases occurs alongside risks from natural disasters or facility accidents. In any such event, it is crucial to rapidly assess the release composition and extent of response and remediation activities. Therefore, the deployment of an effective, resilient and autonomous radiation monitoring network is pivotal both during and after an incident. Underpinning this assessment is a detailed understanding of the pre-event or background, radiation levels, the knowledge of which is also essential in assessing a population’s dosimetric exposure to, and impact from anthropogenic and naturally occurring/varying sources of ionizing radiation. Presented here is a fully operational cloud-based spectroscopic radiation mapping platform comprising IoT modules compatible with cellular networks, without modification, in over 180 countries. Combined with locally roaming vehicles, a continuous multi-pass radiological characterization of an urban environment was performed. Such IoT devices are deployable as either individual sensors for specific localized temporal events or integrated over a greater time period (and area) to represent a larger static sensor. Over several months of continued operation, more than 1000 000 individual location-referenced gamma-ray spectra were collected and securely uploaded, in real-time, to an online cloud database and automatically characterized via a custom multi-step workflow. Fine-scale local variations in the radiological fingerprint of a 1 km × 1 km urban area were subsequently rendered in near-real-time to an interactive secure online graphical dashboard for temporal, spatial and spectral interrogation by the user. Considerations for the automated ‘elastic’ handling of ever-expanding volumes of input data have been carried out, facilitating propagation and expansion of the system’s database without human input.

Radiological Characterization and Safety during Decommissioning of aNuclear Reactor

Radiological Characterization and Safety during Decommissioning of aNuclear Reactor

Radiological and X-Ray Diffraction Characterization of Bauxite and Rutile Ore Contaminated Environment in Kanam and Wase Mineral Exploration Sites, Plateau State-Nigeria

Radiological and X-Ray Diffraction Characterization of Bauxite and Rutile Ore Contaminated Environment in Kanam and Wase Mineral Exploration Sites, Plateau State-Nigeria

Seeing radioactivity: Gamma-ray imaging technique applied to TRIGA RC-1 Research Reactor in ENEA Casaccia

Current radiological characterization protocols applied in nuclear installations provide a valuable set of information used to assess level and distribution of radioactivity, which is a crucial information in the plant management. Nevertheless, typical routines may present limitations that novel technologies can alleviate. In this work, a new-generation 3D pixelated CdZnTe gamma imaging and spectrometer detector has been used at TRIGA RC-1 Research Reactor in ENEA Casaccia Research Centre to assess its performances in several possible tasks and effectively understand this technology readiness. In particular, three possible tasks have been considered: survey of potentially contaminated area (with determination of known and unknown hot spots), source identification and localization (including neutron sources via their gamma emissions), and quantification of isotope-specific activities in generic components thanks to the point-kernel-based algorithm the system is equipped with. The experience has demonstrated the capability to achieve reliable results in these tasks, with consequences that could impact not only the current characterization protocols but also the way some Nuclear Safeguards and Non-Proliferation operations are performed.

Верифікація коефіцієнтів масштабування, призначених для радіологічної характеризації твердих радіоактивних відходів АЕС за методологією МАГАТЕ. Огляд сучасних підходів

To ensure the safety of repositories used for final disposal of solid radioactive waste (SRW) of nuclear power plants and other nuclear installations, the compliance of their radionuclide contamination levels with valid acceptance criteria has to be monitored. Scaling factors (SF) are used in many world countries to quickly solve the problems with radiological characterization of SRW subject to burial. To ensure the reliability of SF application in different countries, episodic or periodic verification and update of SF values is conducted. The purpose of work is to substantiate the global experience of SF verification, which, according to the IAEA methodology, is used for certification of specific and total activity of difficult-to-measure radionuclides (DTM) in SRW batches destined for disposal. The work addresses the current state of SF methodology application, and analyzes the main steps of its implementation. It was stated that current IAEA recommends declare the need for their verification and update of previously established SFs only, without offering any clear algorithms for implementation of this procedure and terms of its realization. However, in practice, such a procedure is used for radiological characterization of SRW in order to ensure quality guarantees in obtaining information regarding their radiation and other characteristics. This work also examines in detail the experience in applying the SF verification on the examples of several world countries. It was concluded that the verification should be a needed element in ensuring the reliability of SF use for radiological characterization of SRW. The experience of verification by means of SF validation using quantitative criteria is summarized. An algorithm is defined, according to which, and based on obtained results, it is possible to come to a statistically justified decision regarding the further use of existing SFs or recognition of a need in their updating for radiological characterization of new batch of waste

Method development for in-situ radiological characterization of oil-based mud originating from oil industry

Method development for in-situ radiological characterization of oil-based mud originating from oil industry

The MICADO Integrated Gamma Station for Radioactive Waste Packages radiological characterization

The MICADO (Measurement and Instrumentation for Cleaning And Decommissioning Operations) Project of the H2020 Research and Innovation Programme aims to propose a cost-effective solution for non-destructive characterization of nuclear waste, implementing a digitization process that could become a referenced standard facilitating and harmonizing the methodology used for the in-field Waste Management and Dismantling & Decommissioning operations. It employs instruments based on different technologies: an active and passive neutron measurement system, a photo-fission facility, and the ‘Integrated Gamma Station’. Within the MICADO Project, an entire work package has been dedicated to the design and realization of the ‘Integrated Gamma Station’ obtained by combining different gamma detection technologies supporting each other to a comprehensive and effective non-destructive gamma characterization, able to accommodate Radioactive Waste Packages of different sizes. The techniques implemented are i) dosimetry measurements, count rate inspection and raw spectroscopy with the CAEN RadHAND, ii) gamma imaging in open geometry with the CEA Nanopix gamma camera, iii) high resolution gamma spectrometry with the ENEA Tomographic Gamma Scanner (TGS). The latter able to carry out different characterization methodologies, i.e., Open Geometry, Segmented Gamma Scanning, Angular Scanning, and Tomography. This paper describes the layout of the Integrated Gamma Station conceived, its features and detection capabilities, and part of the measurement campaign realized during the MICADO Project.

Radiological characterization of high-energy proton Tantalum targets from CERN-ISOLDE Facility

Radiological characterization of high-energy proton Tantalum targets from CERN-ISOLDE Facility

Field Radiological Characterization for Scrap Yards at Al-Tuwaitha Nuclear Site

In the present study, measurements of alpha/beta contamination and gamma dose rates measurements were carried out in scrap yard contaminated by spillage of sludge contained 238U at Al-Tuwaitha Nuclear Site. Alpha/beta surface soil contamination levels were directly measured in the field at January 2016 using RadEye SX monitor. Gamma dose rates measurements were conducted using RadEye PRD. The results showed that alpha/beta surface soil contamination levels varied from 0.1 for uncontaminated areas and reach 2.8 Bq/cm2 for contaminated areas, with an average value of 0.8 Bq/cm2, which is more than 6 times the local natural background level. Results of dose assessment indicate that, the potential radiation doses to on-site workers from site contaminants were estimated to be in the order of 0.036 mSv/y, which was considered within the occupational dose limit of 20 mSv/y recommended in the International Atomic Energy Agency (IAEA) GSR Part 3 (2014). However, the mean dose rate reaches 4.5 times the background level, indicating that remediation of site contaminants is recommended to ensure environmental safety.

Radiological Study of Water for Human Use and Consumption in Rural Areas of the Central Zone of the State of Veracruz, Mexico

A study and spatiotemporal radiological characterization of water for human use and consumption in the main rural populations of the center of the State of Veracruz was carried out, covering 22 municipalities. The objective was to estimate the annual effective dose as a function of the concentration of gross alpha and beta activity. For this purpose, a low background proportional flux detection system calibrated with NIST-traceable radioactive standards was used. Sampling included only wells, springs, and lagoons in rural areas that supply water to these populations. The decision was based on the fact that these do not have a physicochemical treatment and was carried out during the dry and rainy seasons, which became factors of impact on the radiological material. The analysis included the results of 195 samples from 22 municipalities which showed ranges in the gross alpha of 0.052-0.95 BqL-1 with a mean of 0.376 ±0.101BqL-1 and a gross beta of 0.034-1.48 BqL-1 with a mean of 0.389 ±0.108 BqL-1. The comparison of the values obtained with respect to those of other countries and their complement with analysis of variance showed that there was a significant difference, particularly, for the results of gross alpha in the municipality of Alto Lucero de Gutierrez Barrios and gross beta in Nautla and Tecolutla in dry and rainy seasons (at a probability of p≤0.05 with the Tukey-Kramer HSD statistical test). A correlation between gross alpha and gross beta was also performed with an r of -0.18 and -0.44 in dry and rainy seasons. This means that among the radionuclides, the major sources of beta radiation are uranium and thorium decay series radionuclides. For the determination of gross alpha, the municipalities in the mountainous zones showed lower values of this activity than the municipalities in the coastal zone. Gross alpha activity values of 0.95 ± 0.11 BqL-1 were detected in the municipality of Alto Lucero de Gutiérrez Barrios in the locality of Arroyo Agrio, which exceeded the limit of the Official Mexican Standard.

Optimal radiological gallbladder lesion characterization by combining visual assessment with CT-based radiomics.

Differentiating benign gallbladder diseases from gallbladder cancer (GBC) remains a radiological challenge because they can appear very similar on imaging. This study aimed at investigating whether CT-based radiomic features of suspicious gallbladder lesions analyzed by machine learning algorithms could adequately discriminate benign gallbladder disease from GBC. In addition, the added value of machine learning models to radiological visual CT-scan interpretation was assessed. Patients were retrospectively selected based on confirmed histopathological diagnosis and available contrast-enhanced portal venous phase CT-scan. The radiomic features were extracted from the entire gallbladder, then further analyzed by machine learning classifiers based on Lasso regression, Ridge regression, and XG Boosting. The results of the best-performing classifier were combined with radiological visual CT diagnosis and then compared with radiological visual CT assessment alone. In total, 127 patients were included: 83 patients with benign gallbladder lesions and 44 patients with GBC. Among all machine learning classifiers, XG boosting achieved the best AUC of 0.81 (95% CI 0.72-0.91) and the highest accuracy rate of 73% (95% CI 65-80%). When combining radiological visual interpretation and predictions of the XG boosting classifier, the highest diagnostic performance was achieved with an AUC of 0.98 (95% CI 0.96-1.00), a sensitivity of 91% (95% CI 86-100%), a specificity of 93% (95% CI 90-100%), and an accuracy of 92% (95% CI 90-100%). Machine learning analysis of CT-based radiomic features shows promising results in discriminating benign from malignant gallbladder disease. Combining CT-based radiomic analysis and radiological visual interpretation provided the most optimal strategy for GBC and benign gallbladder disease differentiation. Radiomic-based machine learning algorithms are able to differentiate benign gallbladder disease from gallbladder cancer. Combining machine learning algorithms with a radiological visual interpretation of gallbladder lesions at CT increases the specificity, compared to visual interpretation alone, from 73 to 93% and the accuracy from 85 to 92%. Combined use of machine learning algorithms and radiological visual assessment seems the most optimal strategy for GBC and benign gallbladder disease differentiation.

Hybrid Monte Carlo/deterministic activation calculation to support the decommissioning of PWRs: Validation against data from the thermal shield of the Enrico Fermi NPP

The progressive aging of nuclear power plants (NPPs) in the world is a relevant issue for the nuclear industry.The radiological characterization of the reactoris usually performed using a combination of sampling campaigns and computer simulations, and the latter are particularly useful if measurements are limited.This paper describes the development of a four-step, hybrid Monte Carlo/deterministic calculation scheme to evaluate the residual activation of a pressurized water reactor, focusing the analysis on the Enrico Fermi power plant in Italy. The scheme performance is evaluated using the ratio between the calculated specific activities and the measured ones (C/M ratio) for each point and isotope considered. The overall performance is satisfactory, as the scheme provides conservative results with a good accuracy, without excessive overestimations. The present computational scheme can be adapted to study the lifetime of a NPP, thus providing a useful support tool for the dismantling process in NPPs.

Chemical, radiological and microbiological characterization of a drinking water source: a case study.

This study examined water samples from a local stream in Central Serbia, which was consumed as drinking water. The chemical parameters (chemical oxygen demand, COD; pH, total concentration of dissolved substances and electrical conductivity), the concentration of major, trace and radioactive elements in the water as well as the content of those from the environment, were examined. In addition, the microbiological quality of the water was inspected. The water samples were acidic (pH from 5·27-5·69) and COD ranged in upper permissible limits (up to 6·25 mg O2 l-1 [WR]). The concentrations of major, trace and radioactive elements, including radon, were below maximum contaminant levels. The water contained a higher number of total coliform bacteria (TCB) than it was allowed (˃10 colony-forming units (CFU) in 100 ml of water) as well as enterococci and Escherichia coli. The characterization of the isolated bacteria indicated that two isolates demonstrated proteolytic activity, while full antibiotic resistance was not detected. The isolates showed moderate to strong ability to produce biofilm, while the isolates of E.coli were nonpathogenic. The results indicated that examined water samples were not microbiologically and chemically safe, therefore, the usage of analysed water was not recommended as a water supply. Further research needs to include more frequent monitoring in order to propose measures for the improvement of the water quality and prevention of health risks for consumers.

A Technique for Metallic Waste Characterization and Segregation in Management Routes

Adequate radiological characterization is important for optimization of metallic waste management. For decommissioning planning, the objective is to obtain a radiological understanding of the involved installation. The characterization at this stage could be carried out by means of: 1) neutron activation calculations based on reactor design and neutron flux; 2) dose rate measurements; 3) in-situ gamma spectrometry; 4) sampling for determination of the scaling factors in activated and contaminated components. During dismantling, in-situ characterization is carried out to classify and package the generated waste. Then, the packages are monitored for assessment of activity and determination of the management route. The selection of cutting and decontamination techniques should be based on accurate determination of the radionuclides inside the material and/ or on the surface contamination. . It is important to decide in which cases the decontamination will be efficient as well as to select the appropriate decontamination techniques based on whether the waste is slightly activated or contaminated or both. Α Semi-empirical technique for optimization of determination of contamination and activation of components and metallic waste is under development based on combination of gamma spectrometry measurements and MCNPX Monte Carlo simulations. Firstly, the technique aims at reduction of the uncertainties related to the density and activity distribution. The specific activities inside and on the surface of the materials could be determined by using the measurement results of the proposed non-destructive technique in combination with the use of the scaling factors for activation and/ or contamination.

Comparison of Real and Generated by MCNP Simulation Spectrums for Validation of Neutron Activation Calculations

The objective for decommissioning planning, is to obtain a radiological understanding of the involved installation. The characterization at this stage could be carried out by means of: (a) neutron activation calculations based on reactor design and neutron flux; (b) dose rate measurements; (c) in-situ gamma spectrometry; (d) sampling for determination of the scaling factors in activated and contaminated components.Neutron activation calculations contains several uncertainties. These uncertainties are based on the input data - such as material data (composition and impurities), neutron flux and energy, nuclear data libraries - and on the methodology of the process and the simulation codes.Taking into consideration all these modeling uncertainties, this work is focused on the development of a technique for validation of the calculations. A non-destructive gamma spectrometry technique by using MCNP6 simulations is under development for interpretation of the resulting gamma-ray spectra of the radionuclides in activated components. In particular, a spectrum will be produced, based on the activities of the main radionuclides in the activated component and the results of MCNP6 simulations. This spectrum will be compared with the experimental spectrum.Furthermore, the radiological characterization of activated components, which appeared with surface contamination, is essential for the decision making process during decommissioning. The cutting techniques to be followed in order to reduce the production of secondary waste and limit the doses to personnel and the selection of decontamination techniques should be based on accurate determination of the radionuclides inside the material and/ or in the surface contamination. The proposed method could also be helpful in this case. The activities inside and on the surface of the components could be determined by comparing the experimental spectrum with that produced by MCNP6 simulations, using the arisen activities from the scaling factors and the dose rate measurements.

Radiological and Structural Characterization of Raw and Alkali-Activated Wood Ash and Metakaolin Blends

The aim of the presented research was to investigate the application possibility of wood ash and metakaolin to obtain alkali-activated materials as relatively new materials in the building industry. Thus, in order to assess the adequate use of these waste materials, structural and radiological characteristics should be considered. Until now, the focus has been on ash from thermal power plants produced by burning coal, but a large part of households in our country have individual fireplaces in which wood is used as the basic raw material; thus, it is very interesting to measure the activity concentration of radionuclide in wood ash as well as the possibility of reusing that ash for other purposes. All materials were studied, in terms of physical and chemical characteristics, by methods such as X-ray diffraction (XRD), Fourier transform infra-red (FTIR) spectroscopy, and scanning electron microscopy and energy-dispersive X-ray spectroscopy (SEM/EDS). XRD measurements of wood ash samples showed that it consists of calcite and larnite. FTIR spectroscopy revealed a polymeric Si–O–Al framework in alkali-activated materials and Si–O bonding bands corresponding to silicon dioxide. Determination of radionuclide content was performed by means of gamma-ray spectrometry. Results showed that the alkaline activation process led to the decrease in the activity concentration of radionuclides detected in the measured samples. External radiation hazard index (Hex) for wood ash was reduced by more than 50% after alkali activation. The results of activity concentration measurements in alkali-activated materials indicate potential for their safe application in building construction.

Craniofacial Malformations as Fundamental Diagnostic Tools in Syndromic Entities.

Background: A long list of syndromic entities can be diagnosed immediately through scrutinizing the clinical phenotype of the craniofacial features. The latter should be assisted via proper radiological interpretations. Patients and Methods: Different children aged from 1 month to 12 years were referred to our departments seeking orthopedic advice. Primarily, all received variable false diagnoses in other institutes. Two unrelated boys of one month and 12 months were falsely diagnosed as having positional plagiocephaly associated with contractures of idiopathic origin. Two unrelated boys of 14 months and 2 years were diagnosed with pseudo-hydrocephalus and non-specific syndrome, and were referred to explore their skeletal development. Two unrelated girls of 4 years old and 12 years old presented with multiple contractures were referred because of progressive scoliosis. A 4-year-old girl was referred with a false provisional diagnosis of facial diplegia. All children underwent detailed clinical, radiological and tomographic phenotypic characterizations and genetic testing, respectively. Results: Idaho syndrome (craniosynostosis associated with multiple dislocations) was the final diagnosis in the two unrelated boys with plagiocephaly and multiple contractures. Two children falsely diagnosed with pseudo-hydrocephalus and non-specific syndrome, were diagnosed with Silver–Russell syndrome (RSS). Contractural arachnodactyly Beals (CAB) was confirmed as the definitive diagnosis in the two unrelated girls with progressive scoliosis and multiple contractures. Parry–Romberg syndrome (PRS) associated with congenital lumbar kyphosis was the final diagnosis of the girl with the diagnosis of facial diplegia. Hypomethylation of ICR1 was confirmed in the RSS patients. Whole exome sequencing (WES) revealed a heterozygous mutation in the PRS patients. WES and array-CGH showed that no relevant variants or copy number variations (CNV) were identified in the CAB patients. Conclusions: On the one hand, newborn children can manifest diverse forms of abnormal craniofacial features, which are usually associated with either major or minor dysmorphic stigmata. A cleft lip/ palate is a major craniofacial malformation, and frontal bossing or a disproportionate craniofacial contour can be falsely considered as a transient plagiocephaly, which is spontaneously resolved by time. On the other hand, many physicians fall into the problem of deeming a countless number of diseases, such as contractures, as an idiopathic or non-specific syndrome. The latter stems from limited clinical experience. Therefore, failing to establish between the onset of the deformity and other inexplicit abnormal features that the patient or their immediate families or relatives carry is the final outcome. In this study, we used, for the first time, a reconstruction CT scan to further delineate the congenital disruption of the craniofacial anatomy and the other skeletal malformation complex.

Chemical and Radiological Characterizations of the Desert Dust Coming from Northern Africa to Batman (Southeastern Turkey)

This work investigates the chemical and radiological characterizations of the dust coming from Sahara in North Africa to Batman city in the southeastern region of Turkey on 20 May 2017. According to meteorological maps, the source region of the dust storm that took place in Batman was found to be Libya, which is supported by the NOAA HYSPLIT model’s back trajectory analysis. XRD analyses show that the common minerals of the dust samples are quartz, feldspars, calcite, dolomite, hematite and rutile. Chemical patterns of some major, minor and trace elements in dust samples are generally consistent with those of Saharan Dust composition. The heavy metals in the dust follow the decreasing concentration order: Mn > Zn > Cr >Ni > Cu > Pb. The enrichment factors (EF) of these elements show anthropogenic contamination effects with regard to Zn, Cr and S elements in dust samples. The corresponding values of the radionuclides, the absorbed dose rates in the air and the annual effective doses in the samples were also evaluated and compared to the internationally recommended values. The findings are supposed to be beneficial for tracking and evaluating any environmental pollution inventory in this area.

Pancreatic Neoplasms: CT Evaluation of the Uncommon Presentations of Common Lesions and Common Presentations of the Uncommon Lesions!

Pancreatic masses are commonly encountered entities in radiology practice. Pancreatic ductal adenocarcinomas (PDAC) are the commonest pancreatic malignancies that typically present as infiltrative hypodense focal masses in the pancreatic head, which are hypoattenuating to the pancreatic parenchyma on pancreatic parenchymal and venous phases. However, there are various atypical imaging features of PDACs that create a diagnostic dilemma like tumor in body or tail, diffuse glandular involvement, isoattenuating tumors, cystic changes, or calcifications. Also, few relatively uncommon pancreatic malignancies like pancreatic neuroendocrine tumors, cystic pancreatic tumors, pancreatic lymphoma, and pancreatic metastases present with overlapping features. Accurate radiological characterization of pancreatic masses is important for optimal management and prognostication. Thus, it is imperative for radiologists to be aware of all the uncommon presentations of common pancreatic lesions and common presentations of uncommon pancreatic lesions to avoid erroneous interpretations and establishing the correct diagnosis.

From Spatial Characterisation to Prediction Maps of the Naturally Occurring Radioactivity in Groundwaters Intended for Human Consumption of Duero Basin, Castilla y León (Spain)

According to the European Council Directive 51/2013 EURATOM, the radionuclide content in human consumption waters must comply with the stated recommendations to ensure the protection of public health. The radiological characterisation assessed in Laboratorio de Radiaciones Ionizantes y Datación of Universidad de Salamanca, in more than 400 groundwater samples gathered from intakes intended for human consumption from the Castilla y León region (Spain), has provided worthwhile data for evaluating the spatial distribution of the radioactivity content in the Duero basin. For this purpose, geostatistical exploration and interpolation analysis, using the inverse distance weighting (IDW) method, was performed. The IDW prediction maps showed higher radioactivity occurrence in western and southern areas of the study region, mainly related to the mineralogical influence of the igneous and metamorphosed outcroppings in the Cenozoic sediments that formed the porous detritic aquifers of the Duero basin edges. The hydraulic characteristics promote the distribution of these radioactivity levels towards the centre of the basin as a consequence of the unconfined nature of the aquifers. Prediction maps provide a worthwhile tool that can be used for better planning and managing of groundwater monitoring programmes.