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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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At least 1,351 records · Page 75
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

Dosimetry and cancer risk estimations for different radiation protection solutions at decommissioning a contaminated nuclear power plant site

Contaminated sediments originating from dredging activities in a nuclear power plant site were placed in a pond, which has to be taken into consideration during the future decommissioning process. The sediments have to be handled to free release the site. The radionuclides Co-60 and Cs-137 were identified and the activity concentrations (Bq/kg) were quantified in the range of 10–6000 and 5–50 Bq kg -1 , respectively. The absorbed dose rate to individuals of various ages and sex present at the site of the dry pond area was estimated. The radiological impact in terms of lifetime attributable risk (LAR) and effective dose were calculated. For a 30-year-old male exposed during one year without any action regarding the sediments in the dried out pond, the LAR was predicted to be 0.0027, which recalculated to effective dose corresponds to 7.6 mSv year -1 . The calculations show that countermeasures will be needed for the contaminated site.

61 RADIATION PROTECTION AND DOSIMETRY↗
DOE OSTI2016

B{sub 4}C protective coating under irradiation by QSPA-T intensive plasma fluxes

The effect of the QSPA-T pulsed plasma irradiation on the crystalline boron carbide B{sub 4}C coating was examined. The duration of the rectangular plasma pulses was 0.5 ms with an interval of 5–10 min between pulses. The maximum power density in the central part of plasma stream was 1 GW/m{sup 2}. The coating thickness varied from 20 to 40 μm on different surface areas. Modification of the surface layers and transformation of the coating at elevated temperature under plasma pulse irradiation during four successive series of impulses are described. It is shown that the boron carbide coating withstood the full cycle of tests under irradiation with 100 plasma pulses with peak power density of 1GW/m{sup 2}. Constitutive surface deterioration was not detected and the boron carbide coating kept crystal structure B{sub 4}C throughout the irradiation zone at the surface depth no less 2 μm.

36 MATERIALS SCIENCE↗
DOE OSTI2016

A Certified Health Physicist’s Reflections on a 40-Year Career in Radiation Protection

This is a reflection from a certified health physicist regarding his becoming aware, during his 40-year career, that the linear no-threshold (LNT) model and the associated As Low As Reasonably Achievable concept have no scientific basis and make no positive contribution to radiation safety. They should be replaced by an alternative, scientifically based model that includes a threshold, below which there is no harm, and recognition of hormesis and the adaptive response, which reflect the benefits of low-dose and low-dose-rate radiation exposure. Continued use of the unscientific LNT model is not conservative, as most regulators complacently claim but actually harmful. Examples of these harmful impacts in the areas of nuclear power, nuclear medicine, and environmental management are included.

61 RADIATION PROTECTION AND DOSIMETRY↗
DOE OSTI2014

Energy-Saving Melting and Revert Reduction Technology (E-SMARRT): Use of Laser Engineered Net Shaping for Rapid Manufacturing of Dies with Protective Coatings and Improved Thermal Management

In the high pressure die casting process, molten metal is introduced into a die cavity at high pressure and velocity, enabling castings of thin wall section and complex geometry to be obtained. Traditional die materials have been hot work die steels, commonly H13. Manufacture of the dies involves machining the desired geometry from monolithic blocks of annealed tool steel, heat treating to desired hardness and toughness, and final machining, grinding and polishing. The die is fabricated with internal water cooling passages created by drilling.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2014

Individual Radiation Protection Monitoring in the Marshall Islands. Utrōk Atoll (2010-2012)

As a hard copy supplement to the Marshall Islands Program website (https://marshallislands.llnl.gov), this document provides an overview of the individual radiological surveillance monitoring program established in support of residents of Utrōk Atoll and nonresident citizens of the Utrōk Atoll population group, along with full disclosure of verified measurement data (2010-2012). The Utrōk Atoll Whole Body Counting Facility has been temporarily stationed on Majuro Atoll and, in cooperation with the Utrōk Atoll Local Government, serves as a national radiological facility open to the general public.

61 RADIATION PROTECTION AND DOSIMETRY↗
DOE OSTI2014

Fire Protection Significance Determination Process (SDP) P-108

This report includes the following outline of the course presented: Day 1: –Module 1: Introduction to Fire SDP Philosophy and Example Problem –Module 2: Concepts, Terminology, and Fire Scenario Introduction –Module 3: Process Overview •A quick trip through Phases 1 and 2 •Day 2: –Module 4: Phase 1 Details –Module 5: Phase 2 Details •Day 3: –Module 5: Phase 2 Details (continued) –Module 6: Special Topics •Module 6A – High Energy Arcing Faults in Electrical Distribution and Switching Equipment •Module 6B – Cable Tray Fires •Module 6C – Reverse Engineering The Hot Gas Layer •Module 6D: Flexibility –Discussion and Closing.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2017

MN471016, Radiological Protection Procedures Manual, Chapter 13: Feedback and Improvement

This chapter describes the Sandia National Laboratories (SNL) processes for feedback and improvement of radiological operations, including triennial self-assessment (TSA) and radiological process improvement reports (RPIR). This chapter applies to all radiological activities performed by Members of the Workforce (MOW). Certain operations are outside the scope of this manual and do not require self-assessments or use of the RPIR process. See the "Introduction" for exemptions to the requirements of this manual.

61 RADIATION PROTECTION AND DOSIMETRY↗
DOE OSTI2020

Artificial Intelligence for Digital Security and Protections

Proper functioning of nuclear power plants relies on a mix of well-regulated human and machine-driven workflows. This regulation supports nuclear safety through a series of processes and many of the tasks that support these processes have a repetitive nature that make artificial intelligence (AI) informed by machine learning (ML) a potential aid in a variety of tasks. AI is being evaluated for activities that include inspections, fuel processing, monitoring, and other activities. The introduction of any new technology presents a potential new attack vector. In the case of AI/ML, there are many attacks that have already been discovered and over time the attacks can be expected to follow the growth pattern observed in cyber security. While future planning is necessary, current efforts need to be established now to predict the threat emergence over the next year 10 years and mitigate potential threats. Based on these observations, AI/ML will need to become trustworthy, which corresponds to techniques and procedures that emphasize AI explainability along with resilience techniques to data, algorithms, models, and systems. This kind of system robustness is the foundation for defenses against AI/ML-specific attacks. Attempting to look forward and take a broad view of capabilities provides input to research roadmaps and the ability to distill vulnerabilities into specific use cases may provide greater assistance in understanding the technology benefits while introducing new risks. The impact of current and future AI in three areas—capabilities, challenges, and recovery strategies—represents an initial attempt at balancing both.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗
DOE OSTI2022

Integrated Pest Management (IPM) for Early Detection Algal Crop Protection. Final Report

During large-scale, outdoor algal biomass growth, production strain(s) are subject to attack by pathogens, predators, and non-productive competitors, compromising the biomass yield. The project team at UCSD developed and demonstrated the effectiveness of Volatile Organic Compound, VOC, analysis via mass spectrometry (MS) as an early detection system for the presence of production algal ponds infection. The MS detection can then trigger high-resolution melt analysis (HRMA) and enhanced quantitative PCR (qPCR) to identify predatory or pathogenic species precisely. This study gathered the foundational data informing how wholly automated systems monitor the health of production ponds. By detecting the presence of low molecular weight VOCs in the air space above ponds, the instrument was able to mimic “sniffing” the health of the algae pond. This early warning system will be free growers from time-consuming and costly regular surveillance of ponds with the current techniques, such as qPCR and flow-cam assays, which are slower, less sensitive, and not easily fully automated, resulting in increased production efficiency through the reduction of crop loss. This project demonstrated that Chemical Ionization Mass Spectrometry, CIMS, could serve as a real-time monitor of ponds health tracking up to 100 different VOCs simultaneously for continuous periods up to 60 days without interruption, signaling infection within an algal crop 24 to 36 hours prior to techniques such as qPCR and microscopy. While mass spectrometry is an expensive tool, this simple VOC sampling system proved not only to be sensitive and robust but could to multiplexed to monitor several ponds, lowering the overall cost serially. This technology demonstrated a reduction in biomass production cost by approximately 50% compared to growers not employing any detection methodology.

09 BIOMASS FUELS↗
DOE OSTI2023

Radiation Protective Coveralls for Fermilab’s SPOT Robot

Fermilab’s Accelerator Division recently purchased a SPOT robot from Boston Dynamics to be used to automatically measure the residual radiation in the beamline tunnels. Fermilab will work with the College of DuPage Fashion Studies Department to design and develop a prototype Tyvek-garments (coveralls and booties) that can be easily used and replicated by the Fermilab operators to shield the SPOT robot from collecting radioactive dust while deployed.

43 PARTICLE ACCELERATORS↗
DOE OSTI2024

Joint Comments from the Department of Energy, National Nuclear Security Administration (DOE NNSA) Los Alamos Field Office and Triad National Security, LLC on the U.S. Environmental Protection Agency’s New Mexico State-Wide Municipal Separate Storm Sewer System Strawman General Permit

In December 2020 and March 2021, EPA issued two MS4 strawman permit drafts specific to the Los Alamos area. EPA made text changes in the 2 nd strawman permit based on stakeholder comments related to the initial draft. During the public meeting on the Los Alamos area designation decision held on February 13, 2024, EPA staff stated that comments from the past strawman permits would be incorporated into the new MS4 permit to be issued state-wide. However, it does not appear that any of the text changes from the 2 nd Los Alamos area strawman permit were included in this state-wide general MS4 strawman permit. For reference, the 2 nd Los Alamos area revised strawman permit is included with these comments as Attachment 2. Many of the following comments refer to or state EPA’s updated text included in the 2 nd Los Alamos area strawman permit. The updated text from this 2 nd strawman permit that are referenced in the following comments should be applicable state-wide and it is suggested that this past work be reconsidered and incorporated.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2024

A General Overview of Cathodic Protection in Reinforced Concrete

Corrosion of reinforcement steel in concrete is a prevalent issue in infrastructures worldwide, with the direct costs of repair estimated to be $1 trillion annually. Treatment options are complicated by the concrete’s role in the corrosion process. Ordinary, modern-day cement is so alkaline that it maintains a thick passive layer on the steel surface, reducing corrosion to inconsequential rates. However, environmental contaminants in the form of carbon dioxide or chlorides may cause a breakdown in the passive layer, exposing the steel surface to corrosion. Galvanic cells will be free to form due to potential differences along the rebar, and anode sites will create dissolved iron ions that cannot travel far through the still concrete. Thus, rust products will accumulate directly onto the steel/concrete interface. Iron oxides have a much higher volume relative to steel, and even a miniscule amount of rust can produce enough volumetric stress to cause cracking, spalling and delamination of the surrounding concrete, increasing the risk of structural failure. Safeguards and inhibiting technology exist to limit the chances of corrosion initiation by either species, but cracking of the concrete cover and gradual accumulation of contaminants means that corrosion is unavoidable in certain environments and will initiate, given enough time.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Sampling and Analysis Plan for LSL2 Underground Storage Tank Evaluation of PFAS in Soil: Protection of Groundwater

This SAP gathers all pertinent information relevant to the sampling and analysis of soil at the removal site for a former 10,000-gallon UST and reference sites in the vicinity of the excavation site. Data Quality Objectives establishes the process and steps for the acquisition of data. Data Flow Diagram establishes the decisions and next steps. Quality Assurance Project Plan establishes the quality requirements for data collection, including planning, implementation, and assessment of sampling, field measurements, and laboratory analysis. The work is being completed for DOE-SC Pacific Northwest Site Office.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗