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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 73 records · Page 4
All sourcesNASA NTRSDOE OSTI
DOE OSTI2015

A regulatory perspective on the response function method for determining allowable content of a radioactive materials transportation package or storage cask - 15023

In order to simplify shielding design, there has been an increasingly use of a so-called dose rate response function method for determining the allowable contents in radioactive materials (including spent fuel) transportation package and spent fuel storage cask designs. In essence, this approach uses a pre-calculated dose rate at a given location outside the storage cask or transportation package for a given source inside the cask. It assumes that there is a one-to-one relationship between a source inside the cask and the dose rate outside the cask, i.e., a dose rate response function of a source. Thus, the allowable content is obtained by simply dividing the targeted dose rate by the response function. This method converts the complex particle transport problem into a simple arithmetic calculation. If used correctly and prudently, this approach can greatly simplify the shielding design of casks. However, the use of this method must demonstrate the validity of the assumption, that is, the nuclear physics property of the media through which the particle transverses must be similar to that used in computing the response function. Because of the assumptions and approximations, either implicitly or explicitly, made in the models for dose rate response functions, to assure safety the users should also consider the errors in the models and the bias and uncertainties associated with the code used to calculate the response function. This paper reviewed the advantages and some of the major potential pitfalls of this method from the regulatory perspective. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2015

Monte Carlo investigation of a high-efficiency, two-plane Compton camera for long-range localization of radioactive materials

Compton cameras have become an instrument of interest for long-range localization of radioactive materials in nuclear-nonproliferation applications. In this work, a specialized simulation tool was developed for the optimization of a Compton camera through realistic Monte Carlo simulations. This tool can be used for Compton cameras with different geometries. The MCNPX-PoliMi code was used to simulate Compton scatters and photoelectric absorptions in the camera's detectors. The imaging capability is derived from the physics of Compton scattering and the full-energy information obtained in photoelectric absorptions. The simulated system is a 1 1 m2 Compton camera consisting of two planar arrays of photon detectors. Several scintillators were evaluated: LaBr3, CaF2, and NaI(Tl) (all inorganic scintillators), and C9H10 (plastic organic scintillator). The investigation was carried out with a 137Cs source. A minimum detectable activity (MDA) was defined and used to assess the performance of cameras based on different detectors. The simulation results show that C9H10 is a reliable, low-cost, scatter-plane material, increasing the MDA by ~0.2 mCi when compared to a CaF2 scatter plane. On the other hand, the intrinsic background of LaBr3 undermines its above-average energy resolution as the MDA increased by ~0.5 mCi when compared to a NaI(Tl) absorption plane.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2012

REEVALUATION OF WATERBORNE RELEASES OF RADIOACTIVE MATERIALS FROM THE MAYAK PRODUCTION ASSOCIATION INTO THE TECHA RIVER IN 1949-1951

The Mayak Production Association was the first site for the production of weapon-grade plutonium in Russia. Early operations led to the waterborne release of large amounts of radioactive materials into the small Techa River. Residents living downstream used river water for drinking and other purposes. The releases and subsequent flooding resulted in the deposition of sediments along the shoreline and on floodplain soil. Primary routes of exposure were external dose from the deposited sediments and the ingestion of 90Sr and other radionuclides. Study of the Techa River Cohort has revealed an increased incidence of leukemia and solid cancers. These epidemiologic studies are supported by extensive dose-reconstruction activities that have led to the creation of various versions of a Techa River Dosimetry System (TRDS). The correctness of the TRDS has been challenged by the allegation that releases of short-lived radionuclides were much larger than those used in the TRDS. Although the dosimetry system depends more upon the measurements of 90Sr in humans and additional measurements of radionuclides and of exposure rates in the environment, a major activity has been undertaken to define more precisely the time-dependent rates of release and radionuclide composition of the releases. The major releases occurred during 1950-1951. In addition to routine releases major accidental releases occurred. The re-evaluated amount of total release is 114 PBq, about half of which was from accidents that occurred in late 1951. The composition of the radionuclides released has also been re-evaluated; this composition changed with time.

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTAN↗
DOE OSTI2015

Extending the utility of a radioactive material package

Once a package has been certified for the transportation of DOT Hazard Class 7 – Radioactive Material in compliance with the requirements of 10 CFR 71, it is often most economical to extend its utility through the addition of content-specific configuration control features or the addition of shielding materials. The SRNL Model 9977 Package’s authorization was expanded from its original single to twenty contents in this manner; and most recently, the 9977 was evaluated for a high-gamma source content. This paper discusses the need for and the proposed shielding modifications to the package for extending the utility of the package for this purpose.

42 ENGINEERING↗
DOE OSTI2017

SRNL Training Courses for Packaging, Transportation, and Storage of Radioactive Material - 17597

The U.S. Department of Energy (DOE) Packaging Certification Program (PCP), Office of Packaging and Transportation has sponsored a suite of training courses that have been conducted since the early 1990s. Of these training courses, the Savannah River National Laboratory (SRNL) is currently leading the effort for two courses: (1) Management of SARP Preparation, and (2) Nuclear and Other Radioactive Materials Transport Security and Leak Testing. This paper provides an overview of both courses. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2013

Radiological Impact Associated to Technologically Enhanced Naturally Occurring Radioactive Materials (TENORM) from Coal-Fired Power Plants Emissions - 13436

Certain materials used and produced in a wide range of non-nuclear industries contain enhanced activity concentrations of natural radionuclides. In particular, electricity production from coal is one of the major sources of increased human exposure to naturally occurring radioactive materials. A methodology was developed to assess the radiological impact due to natural radiation background. The developed research was applied to a specific case study, the Sines coal-fired power plant, located in the southwest coastline of Portugal. Gamma radiation measurements were carried out with two different instruments: a sodium iodide scintillation detector counter (SPP2 NF, Saphymo) and a gamma ray spectrometer with energy discrimination (Falcon 5000, Canberra). Two circular survey areas were defined within 20 km of the power plant. Forty relevant measurements points were established within the sampling area: 15 urban and 25 suburban locations. Additionally, ten more measurements points were defined, mostly at the 20-km area. The registered gamma radiation varies from 20 to 98.33 counts per seconds (c.p.s.) corresponding to an external gamma exposure rate variable between 87.70 and 431.19 nGy/h. The highest values were measured at locations near the power plant and those located in an area within the 6 and 20 km from the stacks. In situ gamma radiation measurements with energy discrimination identified natural emitting nuclides as well as their decay products (Pb-212, Pb-2142, Ra-226, Th-232, Ac-228, Th-234, Pa-234, U- 235, etc.). According to the results, an influence from the stacks emissions has been identified both qualitatively and quantitatively. The developed methodology accomplished the lack of data in what concerns to radiation rate in the vicinity of Sines coal-fired power plant and consequently the resulting exposure to the nearby population. (authors)

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2018

Performance of detectors used in measurements of radioactive materials deposited in tissues from intakes by wounds

In the care of people injured with wounds with incorporated radioactive material, the basic information is collected, using appropriate detectors, following procedures established in first aid protocol. The reliability of the data collected for medical treatment depends greatly on the metrological performance of the equipment, the experimental set up and the scenario of the occurrence of the accident. The methodology to evaluate the performance of the detectors use the comparison of the attenuation coefficient value of each radionuclide obtained by the attenuation curve of tissue-equivalent material to the theoretical value established by NIST in each experimental set up. The good performance was defined when the difference between the experimental and theoretical value is close to zero. The experimental set ups were chosen according to the types of possible measurements performed in the various scenarios of the radiological accident. The detectors used were Personal Radiation Dosimeter, IdentiFINDER2, Cadmium Telluride and Hyper Pure Germanium. Furthermore, the results for 241 Am showed better performance with HPGe and IdentiFINDER2 shielded. For the 60 Co the best performance occurred with the shielded and collimated IdentiFINDER2. For the 137 Cs, the HPGe detector presented the best performance.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2025

Assessment of Naturally Occurring Radioactive Material (NORM) in Illicit Drugs Using High-Resolution Gamma Spectroscopy

This report documents results assessing the presence of Naturally Occurring Radioactive Material (NORM) in illicit drugs using high-resolution gamma spectroscopy. Specifically, high-purity germanium (HPGe) measurements were conducted at the Drug Enforcement Administration (DEA) South Central Laboratory on 11 samples (referred to as exhibits) including cocaine, fentanyl, heroin, ketamine, LSD, marijuana, methamphetamines, psilocybin mushrooms, and synthetic cannabinoids.

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEA↗
DOE OSTI2012

Fluorescent Functionalized Mesoporous Silica for Radioactive Material Extraction

Mesoporous silica with covalently bound salicylic acid molecules incorporated in the structure was synthesized with a one-pot, co-condensation reaction at room temperature. The as-synthesized material has a large surface area, uniform particle size, and an ordered pore structure as determined by characterization with transmission electron microscopy, thermal gravimetric analysis, and infrared spectra, etc. Using the strong fluorescence and metal coordination capability of salicylic acid, functionalized mesoporous silica (FMS) was developed to track and extract radionuclide contaminants, such as uranyl [U(VI)] ions encountered in subsurface environments. Adsorption measurements showed a strong affinity of the FMS toward U(VI) with a Kd value of 105 mL/g, which is four orders of magnitude higher than the adsorption of U(VI) onto most of the sediments in natural environments. The new materials have a potential for synergistic environmental monitoring and remediation of the radionuclide U(VI) from contaminated subsurface environments.

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEA↗
DOE OSTI2025

Using radioactive material to evaluate decontamination of contaminated electronics

Electronic materials are used everywhere and can get easily contaminated by their use in the field/laboratory. The goal of this project was to use radioactive material to track the effectiveness of a cleaning procedure using an off-the-shelf cleaning gel. Radioactive potassium bromide (KBr) was used as a model contaminant in four contamination scenarios to gauge the effectiveness of a cleaning gel in the decontamination of contaminated raspberry pi’s. Finally, the investigated decontamination technique was found to be 75–97% effective in removing contamination from the tested electronic devices. 95% of the contaminated electronic devices retained their functionality post-decontamination.

38 - RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCL↗
DOE OSTI2025

Explosively Formed Helical Closure for Radioactive Material Packaging

Benefits • Allows for the creation of features in thin-walled metal parts that would otherwise be impossible or impractical to create. • Reduces margin of error during radioactive material package closure. • Increases efficiency of package closure and opening. Applications and Industries • The tooling and method could be used to create closures for any industrial application. There may be use for the geometry produced by the tooling and method that is outside of closures.

Timmons, Darren↗
NASA NTRS1991

Automated technologies needed to prevent radioactive materials from reentering the atmosphere

Project SIREN (Search, Intercept, Retrieve, Expulsion Nuclear) was created to identify and evaluate the technologies and operational strategies needed to rendezvous with and capture aerospace radioactive materials (e.g., a distressed or spent space reactor core) before such materials can reenter the terrestrial atmosphere and then to safely move these captured materials to an acceptable space destination for proper disposal. A major component of the current project SIREN effort is the development of an interactive technology model (including a computerized data base) that explores, in building-block fashion, the interaction of the technologies and procedures needed to successfully accomplish a SIREN mission. The SIREN model will include appropriate national and international technology elements--both contemporary and projected into the next century. To obtain maximum flexibility and use, the SIREN technology data base is being programmed for use on 286-class PC's. The major technical elements for a successful SIREN mission include: ground and space-based tracking, launch vehicles of needed payload capacity, telerobotic systems, sensors, capture technologies, and space transport and disposal. However, Project SIREN also will impose specialized requirements including the use of dextrous aerospace systems capable of properly functioning in intense radiation and thermal environments.

Buden, David↗
NASA NTRS1991

Automated technologies needed to prevent radioactive materials from reentering the atmosphere

Project SIREN (Search, Intercept, Retrieve, Expulsion Nuclear) has been created to identify and evaluate the technologies and operational strategies needed to rendezvous with and capture aerospace radioactive materials (e.g., a distressed or spent space reactor core) before such materials can reenter the terrestrial atmosphere and then to safely move these captured materials to an acceptable space destination for proper disposal. A major component of the current Project SIREN effort is the development of an interactive technology model (including a computerized data base) that explores in building block fashion the interaction of the technologies and procedures needed to successfully accomplish a SIREN mission. This SIREN model will include appropriate national and international technology elements-both contemporary and projected into the next century. To permit maximum flexibility and use, the SIREN technology data base is being programmed for use on 386-class PC's.

Buden, David↗
DOE OSTI2016

Multi-phased Approach for Detection Systems and Measures for Nuclear and other Radioactive Material Out of Regulatory Control

The Office of Nuclear Incident Policy and Cooperation and the Office of Nuclear Security Deterrence and Detection at the U.S. Department of Energy, National Nuclear Security Administration provide a multi-phased approach for detection systems and measures for nuclear and other radioactive material out of regulatory control in cargo shipments. The approach is designed using best practices to deter, detect, interdict, characterize, adjudicate, and recover illicit radiation sources. Two case studies will be presented which demonstrate the multi-phased approach to nuclear security.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2013

The analysis of metal melting application in the management of metallic radioactive materials arising from decommissioning of nuclear installations

Basic characterization of the waste management process during decommissioning of nuclear installations is described in the presented paper. A brief description is given of conditional and unconditional release of materials into the environment. The paper deals also with metal melting as prospective decontamination technique which can significantly reduce metallic radioactive waste. The material and radioactivity flow in the decommissioning process should be followed using the integrated material flow tool that is implemented into the standardized analytical decommissioning parameters calculation code OMEGA. Applying the integrated material flow tool, it is possible to monitor radiological and physical properties of individual material items listed in the nuclear installation input database, from dismantling up to their release into the environment or disposal in repository. Using the OMEGA code and two model databases, several scenarios related to metal melting are evaluated. The impact of applying different input decommissioning parameters on the metal distribution is the main result discussed in the paper. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2015

Stochastic Modeling of Radioactive Material Releases

Nonreactor nuclear facilities operated under the approval authority of the U.S. Department of Energy use unmitigated hazard evaluations to determine if potential radiological doses associated with design basis events challenge or exceed dose evaluation guidelines. Unmitigated design basis events that sufficiently challenge dose evaluation guidelines or exceed the guidelines for members of the public or workers, merit selection of safety structures, systems, or components or other controls to prevent or mitigate the hazard. Idaho State University, in collaboration with Idaho National Laboratory, has developed a portable and simple to use software application called SODA (Stochastic Objective Decision-Aide) that stochastically calculates the radiation dose associated with hypothetical radiological material release scenarios. Rather than producing a point estimate of the dose, SODA produces a dose distribution result to allow a deeper understanding of the dose potential. SODA allows users to select the distribution type and parameter values for all of the input variables used to perform the dose calculation. SODA then randomly samples each distribution input variable and calculates the overall resulting dose distribution. In cases where an input variable distribution is unknown, a traditional single point value can be used. SODA was developed using the MATLAB coding framework. The software application has a graphical user input. SODA can be installed on both Windows and Mac computers and does not require MATLAB to function. SODA provides improved risk understanding leading to better informed decision making associated with establishing nuclear facility material-at-risk limits and safety structure, system, or component selection. It is important to note that SODA does not replace or compete with codes such as MACCS or RSAC, rather it is viewed as an easy to use supplemental tool to help improve risk understanding and support better informed decisions. The work was funded through a grant from the DOE Nuclear Safety Research and Development Program.

61 RADIATION PROTECTION AND DOSIMETRY↗
DOE OSTI2019

Regulatory Design for Transport Security Regulations of Nuclear and Other Radioactive Material

A cornerstone within a nuclear security regime of a country is a legislative and regulatory framework that both regulates the individuals using radioactive and nuclear materials, but also regulates the regulators for their commitments under International Law. When drafting nuclear law and regulations, both technical and legal expertise is needed to ensure the regulation meets the technical requirements for security, but also is legally enforceable within a country’s jurisdiction. While the Primary Nuclear Law, or Enabling Act provides establishes the Competent Authority and responsibilities for nuclear security, regulatory development is where the proverbial, rubber meets the road for requirements. The regulations provide instruction for inspections, authorizations, and managed activities, such as use storage, and transport. Transport Security regulatory development for radioactive and nuclear material is complex because the regulation maybe multi-jurisdictional, multi-modal, and involve multiple stakeholders. Development of transport security regulations requires coordination with other ministerial stakeholders, transport operators, and alignment to international treaties and conventions outside the nuclear domain. This paper provides a brief discussion of the challenges associated with regulatory development for transport security regulations for nuclear and other radioactive materials in transport. The paper will briefly identify key stakeholders, international law involved, and current efforts by the International Atomic Energy Agency (IAEA) in supporting Member States in regulatory development. While active in that regulations are necessary for a robust nuclear security regime, regulatory development is more a slow-burn than an active activity in nuclear security.

Fialkoff, Marc↗