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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 307 records · Page 17
All sourcesNASA NTRSDOE OSTI
DOE OSTI2017

Characterization of Morphology using MAMA Software

The MAMA (Morphological Analysis for Material Attribution) software was developed at the Los Alamos National Laboratory funded through the National Technical Nuclear Forensics Center in the Department of Homeland Security. The software allows images to be analysed and quantified. The largest project I worked on was to quantify images of plutonium oxides and ammonium diuranates prepared by the group with the software and provide analyses on the particles of each sample. Images were quantified through MAMA, with a color analysis, a lexicon description and powder x-ray diffraction. Through this we were able to visually see a difference between some of the syntheses. An additional project was to revise the manual for MAMA to help streamline training and provide useful tips to users to more quickly become acclimated to using the software. The third project investigated expanding the scope of MAMA and finding a statistically relevant baseline for the particulates through the analysis of maps in the software and using known measurements to compare the error associated with the software. During this internship, I worked on several different projects dealing with the MAMA software. The revision of the usermanual for the MAMA software was the first project I was able to work and collaborate on. I first learned how to use the software by getting instruction from a skilled user at the laboratory, Dan Schwartz, and by using the existing user manual and examples. After becoming accustomed to the program, I started to go over the manual to correct and change items that were not as useful or descriptive as they could have been. I also added in tips that I learned as I explored the software. The updated manual was also worked on by several others who have been developing the program. The goal of these revisions was to ensure the most concise and simple directions to the software were available to future users. By incorporating tricks and shortcuts that I discovered and picked up from watching other users into the user guide, I believe that anyone who utilizes the software will be able to quickly understand the best way to analyze their image and use the tools the program offers to achieve useful results.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2026

CWMD Nuclear Forensics Quarterly Report

Analysis and evaluation of nuclear debris is a key component to identify forensic signatures in a post-detonation environment. Currently, methods exist and are practiced in obtaining signatures from post-detonation debris. However, efforts to reduce the timeline in obtaining signatures is continuous within nuclear forensics research and will be forwarded by this research. This education and research project will explore combined material chemistry and separations of radionuclides to provide actionable signatures in less time than standard methods. The research will use the phase distribution of radionuclides in debris to develop targeted and rapid dissolution methods. These dissolution methods will be coupled with microfluidics to achieve samples suitable for analysis within reduced timelines.

and nuclear chemistry↗
NASA NTRS2017

Arc Jet Test and Analysis of Asbestos Free Solid Rocket Motor Nozzle Dome Ablative Materials

Asbestos free solid motor internal insulation samples were recently tested at the MSFC Hyperthermal Arc Jet Facility. Objectives of the test were to gather data for solid rocket motor analog characterization of ablative and in-depth thermal performance of rubber materials subject to high enthalpy/pressure flow conditions. Tests were conducted over a range of convective heat fluxes for both inert and chemically reactive sub-sonic free stream gas flow. Active instrumentation included use of total calorimeters, in-depth thermocouples, and a surface pyrometer for in-situ surface temperature measurement. Post-test sample forensics involved determination of eroded depth, charred depth, total sample weight loss, and documentation of the general condition of the eroded profile. A complete Charring Material Ablator (CMA) style aero thermal analysis was conducted for the test matrix and results compared to the measured data. In general, comparisons were possible for a number of the cases and the results show a limited predictive ability to model accurately both the ablative response and the in-depth temperature profiles. Lessons learned and modeling recommendations are made regarding future testing and modeling improvements that will increase understanding of the basic chemistry/physics associated with the complicated material ablation process of rubber materials.

Clayton, J. Louie↗
DOE OSTI2018

Characterizing the Chemical Behavior of Uranium Compounds for Nuclear Forensics

Better characterization of uranium compounds related to the nuclear fuel cycle is a key goal of the nuclear forensics community. Understanding the chemical behavior of these compounds in various environmental conditions and the effect on observable properties is crucial to the identification of unknown materials. Uranyl fluoride, the hydrolysis product of uranium hexafluoride, is a material of particular interest. Previous studies have suggested that uranyl fluoride may degrade upon exposure to high humidity, but the chemical pathway of degradation was previously not well understood. Our work demonstrates that uranyl fluoride undergoes a chemical reaction with water vapor to form uranyl hydroxide and peroxide species. This understanding will help guide forensic analysis in the future.

Kirkegaard, Marie↗
DOE OSTI2018

Stable-carbon isotope ratios for sourcing the nerve-agent precursor methylphosphonic dichloride and its products

The ability to connect a chemical threat agent to a specific batch of a synthetic precursor can provide a fingerprint to contribute to effective forensic investigations. Stable isotope analysis can leverage intrinsic, natural isotopic variability within the molecules of a threat agent to unlock embedded chemical fingerprints in the material. Methylphosphonic dichloride (DC) is a chemical precursor to the nerve agent sarin. It is converted to methylphosphonic difluoride (DF) as part of the sarin synthesis process. We used a suite of commercially available DC stocks to both evaluate the potential for δ13C analysis to be used as a fingerprinting tool in sarin-related investigations and to develop sample preparation techniques (using chemical hydrolysis) that can simplify isotopic analysis of DC and its synthetic products. We demonstrate that natural isotopic variability in DC results in at least three distinct, isotope-resolved clusters within the thirteen stocks we analyzed. Isotopic variability in the carbon feedstock (i.e., methanol) used for DC synthesis is likely inherited by the DC samples we measured. We demonstrate that the hydrolysis of DC and DF to methylphosphonic acid (MPA) can be used as a preparative step for isotopic analysis because the reaction does not impart a measureable isotopic fractionation. MPA is more chemically stable, less toxic, and easier to handle than DC or DF. Further, the hydrolysis method we demonstrated can be applied to a suite of other precursors or to sarin itself, thereby providing a potentially valuable forensic tool.

Moran, James J.↗
DOE OSTI2026

The influence of iron incorporation on the microstructure and crystal chemistry of UO 2 fuel

The incorporation of dopants into UO 2 is of interest for both doped advanced fuel and nuclear forensics research. Suitable forensics dopants, or taggants, for nuclear fuels are ones that do not adversely affect the performance of the parent material while still being traceable during key stages of the fuel’s life cycle. In this paper, we present our efforts to understand the effects of doping UO 2 with Fe 2 O 3 under multiple parameters, such as Fe concentration (0–3000 wppm), sintering temperature (1673 K, 1773 K, and 1973 K), sintering time (2–12 h), and atmosphere (reducing and inert). Here, we investigated densification behavior, microstructure evolution, and lattice defects based on the geometric densities, scanning electron microscopy (SEM), X-ray diffractograms, and Raman spectra. The effect of Fe on the microstructure and crystal chemistry of UO 2 is very complex, especially at the intermediate temperature (1773 K), where we found that densification kinetics are enhanced and that lattice contraction occurs for doping concentrations greater than 1000 wppm Fe.

Crystallography↗
DOE OSTI2019

Comparative chemical and structural analyses of two uranium dioxide fuel pellets

Here, a comparative investigation of the trace element, U and Pb isotopic compositions, and structural attributes of two uranium dioxide fuel pellets was conducted for nuclear forensic applications. One fuel pellet consists of natural UO 2 (0.71% 235 U), while the other contains enriched UO 2 (3.98% 235 U). Numerous impurities, including transition metals, lanthanides, and main group elements were detected in both fuel pellets with total trace element contents that vary between 9.77 and 11.37 μg/g. The relative abundances of the transition metal impurities in the natural UO 2 fuel pellet are linked to the source U ore and provide important insights into its provenance. X-ray fluorescence spectroscopy was utilized to investigate and compare the macro-(cm)-scale distribution of impurities within each of the fuel pellets. In addition, structural properties of the fuel pellets were examined using powder X-ray diffraction (PXRD) and Raman and infrared spectroscopy. Differences in the intensity of the T2 g U-O stretching vibrational mode were observed in the Raman spectra of the fuel pellets. Lastly, Pb isotope ratios were investigated to potentially differentiate between the natural and enriched UO 2 samples and are linked to the process history of these materials.

36 MATERIALS SCIENCE↗
DOE OSTI2012

Characterization of Delayed-Neutron and Delayed-Gamma Pyroprocessing Emission Signatures Using MCNP6

A computational non-destructive safeguards study has been conducted using the MCNP6 1 radiation-transport code to examine delayed-neutron (DN) current and delayed-gamma (DG) activity ratio (AR) signatures for a conceptual electrorefining and pyroprocessing (EP) model. Spent-fuel (SNF) inventories were prepared using MCNP6 burnup calculations for a generic Westinghouse fuel assembly 2 with 3% and 5% 235 U enrichments; 20-, 30-, 40-, and 50-GWd/MTU burnups; and 3-, 5-, 10-, 20-, and 30-year cooling times to facilitate parametric evaluations. The electrorefining model was patterned after the INL Mark-IV electrorefiner (ER), 3 and treats the distribution of active metals, noble metals, lanthanides, uranium, and TRUs following fuel dissolution and transport to the molten salt eutectic, liquid cadmium cathode (LCC), and cathode mandrel. Signatures have been assessed before and after electrorefining. DG ARs for 134 Cs/ 137 Cs, 134 Cs/ 154 Eu, and 154 Eu/ 137 Cs were developed, and preliminary assessment of new DG ARs that may be better suited for pyroprocessing safeguards was done. Figure 1 shows calculated DN and DG fluxes for 3% enrichment, 20 GWd/MTU burnup, 3 year cooling before electrorefining, with SNF in the ER, and after electrorefining, with material assignment to processing units. Our work suggests that DN and DG markers can be useful for EP forensic analysis.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗
DOE OSTI2020

TA-55 Forensic Support Operations Cross-Training Exercise

As part of the annual FBI/LANL training schedule, a joint training exercise was conducted during the week of 10FEB2020 with FBI HEAT members and LANL Fissile Material Handlers (FMHs). The joint training exercise was conducted in a non-radiological area to reduce cost and ensure the test object would not be contaminated. The exercise test object was fabricated by LANL using surrogate materials to represent an object containing Special Nuclear Material (SNM). Working with Jim Blankenship and Kevin Swearingen, functional requirements of the test object included the following: unclassified, disassembly (to include screws), and moderately heavy. To meet the objectives, the test object was fabricated by welding a custom aluminum box (8” x 8” x 12”) with a lid which was secured by four (4) screws. The custom box housed a track and field shot put (16 lbs.) that was anchored by a hose clamp. The intent of the training was to disassemble the test object and conduct traditional forensic determinations on the parts. This lessons learned report documents all of the associated aspects related to the joint training effort.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2023

Spatially Resolved Characterisation of Low Mass Fraction Uranium Glass Working Reference Materials

Here, we present the results of a study to generate reference glasses that reflect an environment analogous to historic nuclear fallout samples of interest for post-detonation nuclear forensics. The glasses were generated by melting and then quenching SiO 2 , Al 2 O 3 and CaCO 3 powders. Two suites of glasses with three distinct U isotopic ratios were successfully made with enrichments in the 235 U isotope (~ natural [0.72%], ~ 53% and 94%), but the bulk elemental data showed heterogeneity (~ 10% RSD) with U mass fractions ranging from 331.47 to 373.63 μg g -1 . Spatially resolved U isotopic measurements were performed using three mass spectrometry techniques (secondary ion mass spectrometry-single stage accelerator mass spectrometry [SIMS-SSAMS], large geometry [LG] - SIMS, and laser ablation-inductively coupled plasma-mass spectrometry [LA-ICP-MS]) across five National Laboratories. The results showed good agreement with the bulk U isotopic data for the low, medium, and high U mass fractions. We conclude that despite elemental heterogeneity, these samples can serve as useful working reference materials for spatially resolved nuclear fallout analyses, as well as for other related spatially resolved analyses.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Assessment of BOLD and GenBank – Their accuracy and reliability for the identification of biological materials

Taxonomic identification of biological materials can be achieved through DNA barcoding, where an unknown “barcode” sequence is compared to a reference database. In many disciplines, obtaining accurate taxonomic identifications can be imperative (e.g., evolutionary biology, food regulatory compliance, forensics). The Barcode of Life DataSystems (BOLD) and GenBank are the main public repositories of DNA barcode sequences. In this study, an assessment of the accuracy and reliability of sequences in these databases was performed. To achieve this, 1) curated reference materials for plants, macro-fungi and insects were obtained from national collections, 2) relevant barcode sequences (rbcL, matK, trnH-psbA, ITS and COI) from these reference samples were generated and used for searching against both databases, and 3) optimal search parameters were determined that ensure the best match to the known species in either database. While GenBank outperformed BOLD for species-level identification of insect taxa (53% and 35%, respectively), both databases performed comparably for plants and macro-fungi (~81% and ~57%, respectively). Results illustrated that using a multi-locus barcode approach increased identification success. This study outlines the utility of the BLAST search tool in GenBank and the BOLD identification engine for taxonomic identifications and identifies some precautions needed when using public sequence repositories in applied scientific disciplines.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2023

Routine Beryllium-10 analysis from post-detonation debris and geologic materials [Slides]

Beryllium (Be) isotope measurements provide insight into weapon design, yield, etc. Sample preparation nor measurement capability currently existed at LANL. Potential capability directly benefits nuclear forensics venture. PI Goehring has nearly 20 years of Be chemistry experience, including method implementation with difficult samples.

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2019

Results from the third Galaxy Serpent tabletop exercise demonstrating the utility of nuclear forensics libraries in support of an investigation

Galaxy Serpent is a virtual, web-based international ongoing series of tabletop exercises designed to mature the concept of National Nuclear Forensics Libraries (NNFL) and illustrate their utility in answering investigative questions or providing investigative leads as part of an investigation involving nuclear or other radioactive material (R/N) out of regulatory control (MORC). Two prior versions of the exercise have been conducted; the first utilizing surrogate data for spent nuclear fuel as the material of interest, and the second using synthetic sealed radioactive source data. Teams participating in the recently concluded third version of the exercise were provided with synthetic uranium ore concentrate (UOC) data mimicking actual data characteristics (e.g. trace element concentrations), which was used to compile a model NNFL. Teams decided how to organize and interpret the data they were provided, dealt with real world features such as missing data, and assessed discriminating attributes. Next, a hypothetical scenario involving three UOC samples found out of regulatory control was provided, and each team had to assess the self-consistency of the individual sources in the unknown data, and employ their model NNFL as a comparative assessment instrument to determine whether the three UOC materials in question were consistent with any of the types of materials in their library. In conclusion, the design of the exercise, methodologies utilized by participating teams, and aggregate results of the exercise will be presented, along with challenges encountered and benefits realized.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗
DOE OSTI2018

Preface: Chemical forensics

Introduction: This virtual special issue stems from 36 presentations given at the Fourth Chemical Forensics Symposium held 3 - 4 April 2017 as part of the 253rd American Chemical Society (ACS) National Meeting & Exposition in San Francisco, CA, USA. Since 2011, the ACS Division of Analytical Chemistry has hosted symposia that review developments and topics arising in chemical forensics. Chemical forensics is a developing scientific discipline that aims to attribute a chemical (or mixture) of interest to its source by the analysis of the chemical itself or associated material constituents to address investigative, legal or intelligence questions. “Source” refers to how, where and when a chemical was handled or produced. Given past and recent attacks with chemical warfare agents (CWAs) and other toxic chemicals there is a strong need for research and development in chemical forensics for the purpose of finding those responsible for chemical attacks. Hence, many of the papers in this issue deal with the source attribution of toxic chemicals that can be used as weapons. However, given the needs, principles and methods that are shared across different application areas of material provenance or authentication, papers that deal with the source attribution of other illicitly used chemicals and materials are included.

Chemical Forensic↗
DOE OSTI2017

Evaluating and modeling the effects of surface sampling factors on the recovery of organic chemical attribution signatures using the accelerated diffusion sampler and solvent extraction

In this study, an experimental design matrix was created and executed in order to test the effects of various real-world factors on the ability of the (1) accelerated diffusion sampler with solid phase micro-extraction (ADS-SPME) and (2) solvent extraction to capture organic chemical attribution signatures (CAS) from dimethyl methylphosphonate (DMMP) spiked onto painted wall board (PWB) surfaces. The DMMP CAS organic impurities sampled by ADS-SPME and solvent extraction were analyzed by gas chromatography/mass spectrometry (GC/MS). The number of detected DMMP CAS impurities and their respective GC/MS peak areas were determined as a function of DMMP stock, DMMP spiked volume, exposure time, SPME sampling time, and ADS headspace pressure. Based on the statistical analysis of experimental results, several general conclusions are made: (1) ADS-SPME with vacuum (i.e., reduced pressure) increased the amount of detected CAS impurity, as measured by GC/MS peak area, by a factor of 1.7 to 1.9 for PWB under certain experimental conditions, (2) the amount of detected CAS impurity was most influenced by spiked volume, stock, and ADS headspace pressure, (3) the ADS had no measurable effect on the number of detected DMMP impurities, that is, the ADS (with and without reduced pressure) had no practical effect on the DMMP impurity profile collected from spiked PWB, and (4) solvent extraction out performed ADS-SPME in terms of consistently capturing all or most of the targeted DMMP impurities from spiked PWB.

36 MATERIALS SCIENCE↗
DOE OSTI2017

Applications of nuclear physics

Today the applications of nuclear physics span a very broad range of topics and fields. This review discusses a number of aspects of these applications, including selected topics and concepts in nuclear reactor physics, nuclear fusion, nuclear non-proliferation, nuclear-geophysics, and nuclear medicine. The review begins with a historic summary of the early years in applied nuclear physics, with an emphasis on the huge developments that took place around the time of World War II, and that underlie the physics involved in designs of nuclear explosions, controlled nuclear energy, and nuclear fusion. The review then moves to focus on modern applications of these concepts, including the basic concepts and diagnostics developed for the forensics of nuclear explosions, the nuclear diagnostics at the National Ignition Facility, nuclear reactor safeguards, and the detection of nuclear material production and trafficking. The review also summarizes recent developments in nuclear geophysics and nuclear medicine. The nuclear geophysics areas discussed include geo-chronology, nuclear logging for industry, the Oklo reactor, and geo-neutrinos. The section on nuclear medicine summarizes the critical advances in nuclear imaging, including PET and SPECT imaging, targeted radionuclide therapy, and the nuclear physics of medical isotope production. Lastly, each subfield discussed requires a review article unto itself, which is not the intention of the current review; rather, the current review is intended for readers who wish to get a broad understanding of applied nuclear physics.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2013

INFL Guideline On X-Ray Diffraction (XRD)

X-Ray Diffraction (XRD) is an analytical technique used to identify crystalline compounds. It is a bulk technique, though the volume of material sampled is relatively small (approximately 0.01 cm3 ). Specimens are typically examined in the form of powders or solid pieces. XRD data gives precise information about the crystal structure of the material examined, which can be compared to large open databases of crystal structures. The quality of matches of the analyte data to the database can be rigorously quantified. In the case of mixtures of compounds, the relative amounts of each compound can be calculated, although significant errors may exist. In general, XRD is a rapid, easy to use, and robust way to identify materials. It is a widely used and mature technology, with considerable flexibility.

36 MATERIALS SCIENCE↗