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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Presentation of previously STIP'd paper of the same title. Paper accepted for presentation at SORMA West conference. Most of the work was not sponsored. Only limited SDRD support.
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Luminescence dosimetry was applied in the former settlement of Metlino, Southern Urals, Russia as part of a full-scale study to validate the Techa River Dosimetry System (TRDS) 2016 for the upper Techa River region. The village, which was evacuated in 1956, was located 7 km downstream of the release point of liquid radioactive waste by the Mayak plutonium facility. Several brick samples were taken from north-eastern and south-eastern walls of the granary, facing the former Techa river shoreline and floodplain. Samples were all taken at the same height and measured at different depths into the brick. For the majority of brick samples, good Optically Stimulated Luminescence properties of the quartz grains were observed. In some cases, however, strong levels of sensitization and/or signal recuperation were encountered which necessitated adjustment in the measurement protocols. Anthropogenic doses in bricks varied from 1.5 to 6.6 Gy and the horizontal profiles along both walls showed significant variation, which is explained on a qualitative basis. Further, a dose depth profile is observed for selected samples, which is different from the dose depth profile measured and simulated for samples from the north-western wall of the granary in previous studies. This is qualitatively explained by the differences in source configuration.
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The threat of a large-scale radiological or nuclear (R/N) incident looms in the present-day climate, as noted most recently in an editorial in Scientific American (March 2021). These large-scale incidents are infrequent but affect large numbers of people. Smaller-scale R/N incidents occur more often, affecting smaller numbers of people. There is more awareness of acute radiation syndrome (ARS) in the medical community; however, ionising radiation-induced injuries to the skin are much less understood. Here, this article will provide an overview of radiation-induced injuries to the skin, deeper tissues, and organs. The history and nomenclature; types and causes of injuries; pathophysiology; evaluation and diagnosis; current medical management; and current research of the evaluation and management are presented. Cutaneous radiation injuries (CRI) or local radiation injuries (LRI) may lead to cutaneous radiation syndrome, a sub-syndrome of ARS. These injuries may occur from exposure to radioactive particles suspended in the environment (air, soil, water) after a nuclear detonation or an improvised nuclear detonation (IND), a nuclear power plant incident, or an encounter with a radioactive dispersal or exposure device. These incidents may also result in a radiation-combined injury; a chemical, thermal, or traumatic injury, with radiation exposure. Skin injuries from medical diagnostic and therapeutic imaging, medical misadministration of nuclear medicine or radiotherapy, occupational exposures (including research) to radioactive sources are more common but are not the focus of this manuscript. Diagnosis and evaluation of injuries are based on the scenario, clinical picture, and dosimetry, and may be assisted through advanced imaging techniques. Research-based multidisciplinary therapies, both in the laboratory and clinical trial environments, hold promise for future medical management. Great progress is being made in recognising the extent of injuries, understanding their pathophysiology, as well as diagnosis and management; however, research gaps still exist.
Tooth enamel Electron Paramagnetic Resonance (EPR) spectroscopy was used as a method for external dosimetry in the territories contaminated in the 1950s by PA ‘Mayak’ (Urals region) to validate the mean dose estimates predicted by the Techa River Dosimetry System (TRDS). The purpose of this study is to validate the uncertainties of TRDS doses. Ninety percent confidence intervals (90% confidence interval, CI) of dose estimated with both methods were compared for 220 people. All data were grouped according to the width of 90%CI, viz.: (1) 90%CI of EPR-based dose ≤ 90%CI of TRDS prediction (38 cases); (2) 90%CI of EPR-based dose > 90%CI of TRDS prediction (182 cases). About 91% of 90%CIs overlap. In group 1, 100% cases overlap. In group 2, 80% of the cases were non-contradictive (the calculated 90%CI is completely within the measured one). Interval comparison of doses predicted retrospectively and estimated based on individual measurements are non-contradictory and demonstrate a good agreement.
This paper presents a comprehensive systematic review examining the application of augmented reality (AR) and sensor technologies for visualizing ionizing radiation in virtual training environments. The review methodology involved systematic identification and analysis of the relevant literature based on predetermined criteria including publication type, year of publication, application domain, and technological approach. The literature search encompassed publications from 2011 to 2021 across four major academic databases: Web of Science, Google Scholar, IEEE Xplore, and Scopus. Through rigorous screening following PRISMA 2020 guidelines, 23 research articles met the inclusion criteria for detailed analysis. From 404 initial database records, 360 were excluded during title/abstract screening (primarily for lacking AR components, radiation focus, or training applications) and 4 during full-text assessment (all for lacking sensor integration). The findings reveal that AR-based ionizing radiation visualization has been successfully implemented across diverse domains, including nuclear facility operations, medical procedures, CERN research activities, and educational and monitoring applications. The analysis identified multiple dimensions of impact, encompassing distinct benefits, emerging opportunities, and implementation challenges associated with AR deployment for ionizing radiation training. Each of these dimensions is comprehensively examined and documented within this review. Additionally, this study identifies critical research gaps that currently limit the full potential of AR technology in supporting ionizing radiation training programs. These gaps are systematically analyzed and discussed to establish clear directions for future research endeavors in this emerging field.
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The US Department of Energy (DOE) Office of Legacy Management (LM) manages DoE's post-closure responsibilities and ensures the future protection of human health and the environment with respect to sites that have no continuing DOE mission after undergoing remediation. LM's beneficial reuse program promotes the LM strategic goal to sustainably manage and optimize use of public lands. The beneficial reuse program aims to repurpose former contaminated sites to restore the environment, protect the public health, revitalize communities, and spur economic growth. Benefits from the reuse of a site may increase the local tax base, facilitate job growth, utilize existing infrastructure, and enhance or protect natural resources. Beneficial reuse also promotes protectiveness by ensuring activities are compatible with long-term maintenance and protection of public health and the environment, as well as by retaining good stewardship of natural resources. LM actively participates in promoting the economic development vision of the surrounding communities by collaborating with local communities to promote regional or municipal initiatives. The Borough of Middlesex, New Jersey, has prepared the Lincoln Boulevard Redevelopment Plan, which will reinvent a once-viable downtown and enhance the quality of life for the community. The Middlesex South, New Jersey, Formerly Utilized Sites Remedial Action Program (FUSRAP) site lies within the boundaries of this redevelopment area. In support of this development plan, the Borough is interested in acquiring the site for its Department of Public Works and to increase street access in the future commercial district to be built near adjacent properties. The opportunity to put the FUSRAP site into productive use aligns with LM's mission and strategic goals. In support of beneficial reuse activities, DOE can dispose of excess real property using several mechanisms. The two disposal options applicable to the Middlesex south site include (1) utilizing the US General Services Administration (GSA) or (2) using the Title 10 Code of Federal Regulations Section 770, 'Transfer of Real Property at Defense Nuclear Facilities for Economic Development' (known as a '770 transfer') process. Using the 770 transfer requires economic development as the primary driver, and a specific redevelopment proposal must be submitted. If there is no interest in specific economic development, the GSA option becomes the default mechanism for disposal of the property. In the case of the Middlesex south site, the 770 transfer process is being utilized and the Borough has submitted its economic development proposal to LM. Although LM is encouraged by the opportunity to put the site into productive use, the Middlesex south site is currently on the US Environmental Protection Agency (EPA) National Priorities List and remediation is being performed by the US Army Corp of Engineers (USACE) under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). Consequently, any property transfer must meet the requirements under CERCLA Section 120(h), 'Property Transferred by Federal Agencies.' As the groundwater remedy will not be in place for several years, approval would be required from the US EPA administrator and the governor of the state of New Jersey to perform an early transfer of the site (before all response actions have been completed). The time frame for these approvals to occur under the normal process conflicts with the proposed redevelopment schedule; therefore, various options for expedited sale, transfer, or lease of portions of the site to the Borough were evaluated. The subsequent decision on a mutually beneficial path forward was the result of a collaborative effort between LM, USACE, the Borough and its redevelopment team, EPA, and the New Jersey Department of Environmental Protection. (authors)
Accurate measurement of exposure rate from gamma-ray spectral data remains a critical challenge during radiological emergency response operations. Conventional methods rely on pre-defined static conversion factors derived from fixed geometries and isotopic compositions, which often fail to capture real-world environmental variability. This study presents a generalized approach as a "next-step" for converting gamma-ray spectral data into exposure rate using polynomial response models. The method introduces a flexible weighting scheme based on the in-situ detector response to distributed sources, enabling a pathway towards improved correspondence between measured spectra and "ground-truth" exposure rates. Experimental data from sodium iodide NaI(Tl) detectors were used to validate the approach as, at least equivalent to the current count-to-exposure method employed in emergency response CONOPS. Results show that the polynomial weighting model is sufficiently equal to the count-to-exposure method and may help improve accuracy given its adaptability to real-world conditions.
Effective inventory management can be overshadowed by conflicting priorities in organizational procedures, particularly in research-focused institutions such as national laboratories that handle expensive, delicate, and hazardous materials. Here, this study investigated the potential of radiofrequency identification (RFID) technology, currently used for hazardous chemical inventory, in applications with higher metal interference and absorption, specifically pressure release device (PRD) compliance and nuclear container management, at Lawrence Livermore National Laboratory (LLNL). This study was done to document best practices to enhance inventory identification speeds for inventory reconciliation and inventory recall and to explore optimal configurations for RFID implementation compared to traditional manual methods of equipment management. Tests were conducted to determine the ideal RFID tag orientation (read at angles of 0°, 90°, and 270°), various container layouts (linear, separated, curved, operational), and ID methods such as manual, barcode, and RFID performing three trials per method per orientation. Results indicated that 0° was the optimal read angle for minimizing metallic interference, and the operational and curved arrangements significantly outperformed the linear and separated configurations in read speed. 3D printed mounts were developed and tested, increasing the read range of the RFID reader by up to 235% in cases of high metallic interference. The RFID technology demonstrated an average speed increase of 65% over a simplified manual identification, which supports the conclusion that RFID is a more efficient method for large hazardous inventory management and equipment reconciliation. Additionally, capturing meta-data, such as location and date, can be used to query for inventory recall and automated updating of record information.
This work analyses activation calculations for dosimetry materials during a steady-state irradiation in the Transient Reactor Test (TREAT) reactor core. Hence, we developed a workflow based on the Monte Carlo code OpenMC alongside a custom depletion solver. The irradiation-induced activity as a function of time is computed, and several sensitivity studies are performed to evaluate uncertainty. This study has shown activity computations are sensitive to flux amplitude, irradiation time, atoms quantity and microscopic cross sections. Stochastic uncertainties have been propagated to evaluate the activity uncertainty for each dosimetry material. Most uncertainties are below our target of 3%, which demonstrates OpenMC as a powerful predictive and analysis tool. The precise results obtained through this newly developed computation scheme will be used in future experiments to characterize quantities of interest when operating the TREAT reactor in new configurations.
We report the effect of EH 6/7 electron trap centers alone on the performance of high-resolution radiation detectors fabricated on n-type 4H–SiC epitaxial layers. A Schottky barrier detector (SBD) and a metal-oxide-semiconductor (MOS) capacitor detector fabricated using two sister samples derived from the same 50 μm 4H–SiC parent wafer exhibited widely different energy resolutions of 0.4% and 0.9% for 5486 keV alpha particles. An equivalent noise charge model analysis ruled out the effect of the detector capacitance and the leakage current on the resolution of the detectors. Deep level transient spectroscopic studies revealed the presence of two trapping centers in each detector within the temperature scan range 240–800 K. The Z 1/2 center, a potential electron trap, was detected in both the detectors in equal concentration, which suggested that the observed difference in the energy resolution is due to the presence of the other defect, the EH 6/7 center, in the SBD. The capture cross section of the EH 6/7 center was calculated to be three orders of magnitude higher than the second defect [a carbon antisite vacancy (CAV) center] observed in the MOS detector with an activation energy of 1.10 eV, which accounted for the enhanced electronic trapping in the SBD leading to its poor energy resolution. It has been proposed that the EH 6/7 centers in the SBD have likely been reconfigured to CAV pairs during the thermal growth of the silicon dioxide layer in the MOS detector. The proposed formation mechanism of CAV, a stable qubit state for quantum information processing, addresses the outstanding questions related to the role of defect dynamics in their formation.
Cells exposed to ionizing radiation have a wide spectrum of DNA lesions that include DNA single-strand breaks, DNA double-strand breaks (DSBs), oxidative base damage and DNA-protein crosslinks. Among them, DSB is the most critical lesion, which when mis-repaired leads to unstable and stable chromosome aberrations. Currently, chromosome aberration analysis is the preferred method for biological monitoring of radiation-exposed humans. Here, stable chromosome aberrations, such as inversions and balanced translocations, persist in the peripheral blood lymphocytes of radiation-exposed humans for several years and, therefore, are potentially useful tools to prognosticate the health risks of radiation exposure, particularly in the hematopoietic system. In this review, we summarize the cytogenetic follow-up studies performed by REAC/TS (Radiation Emergency Assistance Center/Training site, Oak Ridge, USA) on humans exposed to internal and external radiation. In the light of our observations as well as the data existing in the literature, this review attempts to highlight the importance of follow-up studies for predicting the extent of genomic instability and its impact on delayed health risks in radiation-exposed victims.
Charcoal canisters are a common method of 222 Rn screening. The calibrations of different batches of activated charcoal used in different canister designs are typically performed in large volume controlled environmental chambers with known and controlled radon concentration, temperature, and humidity. Radon screening could be facilitated in locations without ready access to environmental chambers if canisters could be accurately calibrated and undergo quality control in less controlled environments. This study compares charcoal canister calibrations from a highly controlled radon chamber with calibrations from a basement storage area experiencing temporally varying radon. In addition, the impacts of exposure time and spectral region of interest selection on calibration accuracy are investigated by comparing calibrations calculated using three different choices. Approximately 30 mo after calibrations were completed, groups of canisters were exposed for different durations of time to investigate measurement accuracy and calibration validity over an extended time. A digital simulation of charcoal canister kinetics was also performed to establish limits on how stable radon must be in a space for equilibrium-based calibration to be performed there. Overall, the accuracy of measurements using calibrations from each space differed by less than 10% after 2 d exposure time, showing that carefully controlled conditions are not necessary for the accurate calibration of charcoal canisters. Furthermore, measurement accuracy differed by less than 2% for different spectral region selections. Accuracy improved slightly with canister exposure duration. Simulations suggest that radon instability is most tolerable near the beginning of canister calibration exposures, but this merits further experimental study.
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From the countless critical experiments performed in the world during the past century, high-quality integral benchmarks experiments have been collected and gathered into the International Handbook of Evaluated Criticality Safety Benchmark Experiments (ICSBEP Handbook), managed by the International Criticality Safety Benchmark Evaluation Project (ICSBEP) Working Group. This information preservation and dissemination effort is crucial for reactor licensing as well as criticality and radiation transport modeling validation. This summary reports on the status of a tentative benchmark addition to the ICSBEP Handbook. The proposed benchmark arises from legacy operation data of the Oak Ridge National Laboratory (ORNL) Health Physics Research Reactor (HPRR). The HPRR was a small, unmoderated, unshielded fast burst reactor that was used for research in health physics and radiobiology as well as teaching and training. As part of a comprehensive investigation of the available HPRR operation data and characteristics, different possibilities for use of the valuable results were studied. A critical experiment benchmark evaluation was performed, analyzing data coming from sub-critical and critical operation of the HPRR during operator training, steady-state irradiation of samples and before critical bursts. The results of the evaluation do not satisfy for the ICSBEP standards as the benchmark relative standard uncertainty is of about 4% for k eff , and the relative difference between sample calculations and expected k eff results is of about 1.5%. Due to those unsatisfactory results, it was decided not to pursue critical experiments evaluation of the HPRR presently and to focus instead on shielding type data for the creation of a criticality accident alarm system (CAAS) and shielding category benchmark, which is currently very scarce in the ICSBEP handbook—especially concerning critical, pulsed assembly, or reactor operation data. Several dosimetry and shielding experiments from HPRR burst operation were evaluated, with different benchmark metrics as sulfur fluence, Element 57 dose, or neutron fluence at different distances and under different shield materials conditions. An evaluation focusing on the Element 57 neutron dose as a benchmark metric was submitted to the ICSBEP Technical Review Group (TRG) meeting in October 2021, and the inclusion of the evaluation in the ICSBEP Handbook was deferred. The main change proposed by the international experiment evaluation experts is to use the neutron fluence measured by Bonner spheres as a benchmark metric. This represents a quantity closer to that actually measured by the experimentalists of the HPRR compared to the Element 57 dose, which adds another step of data transformation, thus potentially adding uncertainty to the benchmark. The evaluation has been updated and will be submitted to the 2022 ICSBEP TRG meeting for inclusion in the 2023 edition of the ICSBEP Handbook. The evaluation is performed using the KENO and MAVRIC combination from the SCALE 6.2.4 code suite which was previously used in similar CAAS benchmarks to allow for the use of variance reduction techniques.
This report presents the preliminary design (CED-1) of IER-501, a new testbed for pulsed-neutron die-away (PNDA) experiments at Lawrence Livermore National Laboratory (LLNL). The PNDA experiments will be high-quality benchmarks that serve to optimize and validate thermal scattering laws (TSLs), which are high-priority nuclear data for the Department of Energy’s Criticality Safety Program (NCSP). PNDA experiments can be used to generate nuclear data validation benchmarks quickly and cheaply, as they do not require fissile material or a nuclear facility to conduct them.