Nuclear Engineering Commons^™

A Machine Learning Approach To Characterizing Particle Morphology In Nuclear Forensics, Daniel A. Gum

Theses and Dissertations

A machine learning approach is taken to characterizing a group of synthetic uranium bearing particles. SEM images of these lab-created particles were converted into a binary representation that captured morphological features in accordance with a guide established by Los Alamos National Laboratory. Each particle in the dataset contains an association with chemical creation conditions: processing method, precipitation temperature and pH, calcination temperature are most closely tied to particle morphology. Additionally, trained classifiers are able to relate final products between particles, implying that morphological features are shared between particles with similar composition.

Measurement Of The 160Gd(P,N)160Tb Excitation Function From 4 18 Mev, Using A Stacked Foil Technique, Ryan K. Chapman

Theses and Dissertations

A stack of thin Gd, Ti, and Cu foils were irradiated with an 18 MeV proton beam at Lawrence-Berkeley National Laboratory's 88-Inch Cyclotron to investigate the ¹⁶⁰Gd(p,n)¹⁶⁰Tb nuclear reaction for nuclear forensics applications. This experiment will improve knowledge of ¹⁶⁰Tb production rates, allowing ¹⁶⁰Tb to be efficiently created in a foil stack consisting of other proton induced isotopes for forensics applications. A set of 15 measured cross sections between 4-18 MeV for ¹⁶⁰Gd(p,n)¹⁶⁰Tb were obtained using a stacked foil technique. The foil stack consisted of one stainless steel, one iron, fifteen gadolinium, …

Characterization Of Neutron Irradiated Accident Tolerant Nuclear Fuel Cladding Silicon Carbide & Radiation Detector Deadtime, Bader Almutairi

Doctoral Dissertations

“In part I, the pulse shape characteristics generated by a Geiger Muller (GM) detector and recorded by an oscilloscope manually, were investigated. The objective of part I was (1) to find a correlation between pulse shape and the operating voltage; and (2) to assess if pulse shape properties followed distinct patterns comparable to detector deadtime findings reported by a previous study. It was observed that (1) there is a strong correlation between pulse shape and operating voltage, and (2) pulse shape falls in three distinct regions similar to detector deadtime. Furthermore, parts II and III are companions and share the …

Modification Of The Optical Response Of Alpha Quartz Via The Deposition Of Gold Nanoparticles In Etched Ion Tracks, Maria C. Garcia Toro

Doctoral Dissertations

”This study addresses the experimental methods used to develop and characterize plasmonic devices capable of modifying the optical response of alpha quartz via the deposition of gold nanoparticles in etched ion tracks. In the first part of the research, the microstructural characterization of latent and etched ion tracks produced in alpha quartz (α-SiO₂) is presented. Single crystals of α-SiO₂ were irradiated with two highly energetic ions to different nominal fluences. As expected, the morphology of the resulting ion tracks depends on the energy of the incident ion and their stopping powers within the target material. Subsequent chemical …

Monte Carlo And Experimental Analysis Of A Novel Directional Rotating Scatter Mask Gamma Detection System, Julie V. Logan, Darren E. Holland, Larry W. Burggraf, Justin A. Clinton, Buckley E. O'Day Iii

Faculty Publications

Excerpt: This work demonstrates successful experimental operation of a prototype system to identify source direction which was modeled using a library of signals simulated using GEANT and a novel algorithm....

Quantitative Analysis Of Cerium-Gallium Alloys Using A Hand-Held Laser Induced Breakdown Spectroscopy Device, Ashwin P. Rao, Matthew Cook, Howard L. Hall, Michael B. Shattan

Faculty Publications

A hand-held laser-induced breakdown spectroscopy device was used to acquire spectral emission data from laser-induced plasmas created on the surface of cerium-gallium alloy samples with Ga concentrations ranging from 0–3 weight percent. Ionic and neutral emission lines of the two constituent elements were then extracted and used to generate calibration curves relating the emission line intensity ratios to the gallium concentration of the alloy. The Ga I 287.4-nm emission line was determined to be superior for the purposes of Ga detection and concentration determination. A limit of detection below 0.25%was achieved using a multivariate regression model of the Ga I …

Nuclear Engineering At The Air Force Institute Of Technology: A Unique Graduate School Experience For A Unique Set Of Students, Michael B. Shattan

Faculty Publications

In August 2018, the Air University Commander formed a task force to review the Air Force’s Science, Technology, Engineering, and Mathematics (STEM) graduate education programs that are delivered and administered through the Air Force Institute of Technology (AFIT). The study was rooted in strategies to support the 2018 National Defense Strategy, and provided the necessary technologically equipped personnel for the 21st century. The study was commonly referred to as “reimagining AFIT”. Several themes emerged from the study, which include reaching a broader community of Airmen through alternate educational modes (e.g. distance learning, short course etc.), forming strategic educational and research …

Nano Fab Lab 63, Brian K. Deemer, Josh Clemons, Nick Brodine, Delaney Fitzsimmons

Mechanical Engineering

Lawrence Livermore National Laboratories (LLNL) has several steps in the production process for ceramic nanofiber tubes that they would like to improve - electrospinning, cutting, rolling, sealing and heat treating. We undertook the challenge to deliver LLNL with a semi-automated process that efficiently integrates the steps of cutting, rolling, and sealing to save time and improve control over end dimensions. In this document, we discuss the technical background of the manufacturing steps currently followed to create nanofiber tubes, identify which steps are incorporated in our prototype and explain how they will interface with one another, define the design requirements, present …

Isotopically-Resolved Neutron Cross Sections As Probe Of The Nuclear Optical Potential, Cole Davis Pruitt

Arts & Sciences Electronic Theses and Dissertations

Neutron scattering experiments provide direct access to the forces experienced by nucleons in the nuclear environment. Due to the experimental difficulty of cross section measurements with neutrons, isotopically-resolved neutron scattering cross sections are sorely needed as inputs for many nuclear models. This dissertation presents the results from a campaign of isotope-specific neutron total cross section measurements on 16,18O, 58,64Ni, 112,124Sn, and 103Rh from 3-450 MeV and elastic scattering differential cross section measurements on 112,nat,124Sn at 11 and 17 MeV. Equipped with these new data and with computational improvements to the Dispersive Optical Model (DOM), we present DOM treatments of 16,18O, …

Exploring Laser Induced Breakdown Spectroscopy (Libs) For Post-Detonation Nuclear Forensics Debris Analysis, Justin Knoll, Chad Schools, David Fobar

Purdue Workshop on Nonproliferation: Technology and Approaches

In the unlikely but catastrophic event of a nuclear terrorist attack our government leadership will need reliable information to rapidly inform critical decisions. This research explores the use of Laser Induced Breakdown Spectroscopy (LIBS) as a potential analysis tool in the National Technical Nuclear Forensics process. The current state of post detonation nuclear forensics requires ground and air samples be collected and shipped to state-of-the-art laboratories for radiochemical analysis. The samples undergo many measurements and useable data is produced as these measurements are completed. This data flows back into the process to guide additional measurements and inform the process of …

An Experimental And Numerical Investigation Of Flow Accelerated Flibe Corrosion, David B. Weitzel

Nuclear Engineering ETDs

Renewed interest in molten salt reactor technology has brought to light the need for a better understanding of FLiBe corrosion. To this end a flowing FLiBe corrosion test loop was designed to test the flow effects of FLiBe corrosion. The loop consists of a pump, melt tank, and stainless-steel tubing assembly that heats the molten salt to high temperatures and circulates it over test specimens. The experiment has been constructed and has completed initial shakedown testing.

To support the flowing FLiBe experiment, a numerical corrosion model that couples FLiBe electrochemistry, solid metal diffusion, and mass transport was implemented. The model …

Measurement And Analysis Of The Extreme Physical Shock Environment Experienced By Crane-Mounted Radiation Detection Systems, Matthew Boyd, Jennifer Erchinger, Craig M. Marianno, Gene Kallenbach

International Journal of Nuclear Security

At ports of entry, radiation detectors could be mounted on container gantry crane spreaders to monitor cargo containers entering and leaving the country. These detectors would have to withstand the extreme physical conditions experienced by these spreaders during normal operations. Physical shock data from the gable ends of a spreader were recorded during the loading and unloading of a cargo ship by two hard mounted PCB Piezotronics model 340A50 accelerometers and two Lansmont SAVER 9X30 units (with padding). The majority of large shocks were observed in the vertical direction. The Lansmont units recorded mean shocks of 22.215 ± 1.174 and …

Development Of A Switchable Radioisotope Generator, Kyle Mitchell Paaren

Doctoral Dissertations

The Switchable Radioisotope Generator utilizes alpha-induced reactions to produce a combination of photons, neutrons, and protons with varying fluxes dependent on target materials and source geometry. The activity/strength of the secondary radiation is further controlled by manipulating the number of alpha particles that can interact with the target material(s). Analytical equations were solved to confirm secondary radiation production from target materials using average cross sections from TENDL data. TENDL and JENDL data was confirmed by analytically solving for the total alpha-induced cross sections. This information was used to produce the provisional and utility Patent No: US20190013109A1. TENDL data was then …

Call For Abstracts - Resrb 2019, July 8-9, Wrocław, Poland, Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.

Radiolabeled Nanohydroxyapatite As A Platform For The Development Of New Pet Imaging Agents, Stacy Lee Queern

Arts & Sciences Electronic Theses and Dissertations

Positron emission tomography (PET) imaging utilizes drugs labeled with positron emitters to target and evaluate different biological processes occurring in the body. Tailoring medicine to the individual allows for higher quality of care with better diagnosis and treatment and is a key purpose for advancing research into developing new platforms for PET imaging agents. A PET nuclide of high interest for the development of these agents is 89Zr. This can be attributed to the long half-life of 3.27 days and low positron energy of 89Zr.

In this work, we developed a production method for 89Zr using Y sputtered coins that …

Corrosion Dynamics Of Carbon Steel In Used Fuel Container Environments, Dan Guo

Electronic Thesis and Dissertation Repository

The current Canadian used nuclear fuel container (UFC) design uses a pressure‑grade carbon steel (CS) vessel with its outer surface coated with a thin layer of copper. One concern regarding the structural integrity of the UFC design is the potential internal corrosion of the CS vessel. Moisture trapped inside a UFC could condense within the gap between the hemispherical head and the cylindrical body of the vessel. The internal UFC environment will be exposed to a continuous flux of ionizing radiation arising from the decay of radionuclides trapped in the used UO₂ fuel matrix.

This thesis research project investigates …

Spin Alignment Generated In Inelastic Nuclear Reactions, Daniel Hoff

Arts & Sciences Electronic Theses and Dissertations

The spin alignment of inelastically excited 7Li projectiles, when the target remains in its ground state, was determined through angular-correlation measurements between the breakup fragments of 7Li_ (_ + t). It was found that 7Li_ is largely aligned along the beam axis (longitudinal) in this type of inelastic reaction, regardless of the target. This longitudinal alignment is well described by DWBA calculations, which can be explained by an angular-momentum-excitation-energy mismatch condition. These calculations also explain the longitudinal spin alignment of excited nuclei in several other systems, showing the phenomenon is more general. The experiment involving 7Li was performed at the …

Incorporating Collisions And Resistance Into The Transition From Field Emission To The Space Charge Regime, Samuel D. Dynako, Adam M. Darr, Allen L. Garner

The Summer Undergraduate Research Fellowship (SURF) Symposium

Advancements in microelectromechanical systems (MEMS) and microplasmas, particularly with respect to applications in combustion and biotechnology, motivate studies into microscale gas breakdown to enable safe system design and implementation. Breakdown at microscale deviates from that predicted by Paschen’s law due to field emission—the stripping of electrons from the cathode in the presence of strong surface field—and follows the Fowler-Nordheim (FN) law. As injected current increases at this length scale, electrons accumulate in the gap and FN electron emission becomes space charge limited, leading to the Child-Langmuir (CL) law at vacuum and the Mott-Gurney (MG) law at high pressure. While theoretical …

Pnnl Dark Matter Bubble Chamber, Ryan Robinson

STAR Program Research Presentations

The Pacific Northwest National Laboratory (PNNL) prototype bubble chamber is intended to address issues encountered with the current PICO dark matter search detectors and improve the functionality of future experimental designs. The PNNL bubble chamber accomplishes this with a simplified interface between the hydraulic pressure controls and the target vessel and altering the standard chamber design such that it can be easily exchanged and replaced with vessels of various sizes and materials for testing purposes. The chamber itself is a glass vessel which houses perfluorobutane and holds the target fluid above room temperature and atmospheric pressure. The target fluid becomes …

Recommended Corrective Security Measures To Address The Weaknesses Identified Within The Shapash Nuclear Research Institute, Khadija Moussaid, Oum Keltoum Hakam

International Journal of Nuclear Security

The Shapash Nuclear Research Institute (SNRI) data book was issued by the International Atomic Energy Agency (IAEA) in 2013. The hypothetical facility data book describes the hypothetical site, which is divided into two areas: the low-security area, known as the administrative area, and the very high-security area, known as the protected area. The book contains detailed descriptions of each area’s safety and security measures, along with figures of multiple buildings in both areas, and also includes information about the site’s computer networks.

This paper aims to identify security weaknesses related to the institute’s location, the Administrative Area (AA), the Protected …

The Continuing Quest For Missile Defense: When Lofty Goals Confront Reality, Peter J. Pella

Gettysburg College Faculty Books

For almost three quarters of a century, the United States has spent billions of dollars and countless person-hours in the pursuit of a national missile defense system that would protect the country from intercontinental ballistic missiles (ICBM) carrying nuclear warheads. The system currently in place consists of 44 long-range antiballistic missiles stationed in Alaska and California to protect the United States from a possible nuclear weapon carrying ICBM attack from North Korea. After all this effort, this system is still imperfect, being successful only 10 out of 18 tests.

This book will provide an historical description of past efforts in …

Developing Kenya’S Educational Capacity In Nuclear Security Through Nuclear Forensics Research, Hudson Kalambuka Angeyo

International Journal of Nuclear Security

Nuclear energy’s distinctive characteristics give rise to special educational requirements. These requirements are necessary to not only address the danger of nuclear proliferation, but also to build capacity for a secure nuclear fuel circle. In this paper, I assess the status of educational capacity in nuclear security both in response to, and in support of, Kenya’s nuclear power program. I highlight the nuclear security educational infrastructure’s key features in the context of nuclear power, noting the low capacity at Kenyan universities. I identify the steps required to ensure that the country’s dynamic nuclear regulatory infrastructural framework is used effectively to …

An Exploration Of The Optical Detection Of Ionizing Radiation Utilizing Modern Optics Technology, Sean D. Fournier, Adam Hecht, Cassiano De Oliveira, Jeffrey B. Martin, Richard K. Harrison, Charles Potter

Nuclear Engineering ETDs

Modern ultraviolet (UV) cameras, when combined with UV-transmitting lenses/filter arrangements, can be used to detect radiation dose in air. Ionizing radiation excites nitrogen molecules in ambient air, the resulting decay includes weak emission of ultraviolet photons. Previous work has proven this phenomenon is detectable using highly-sensitive electronically cooled cameras traditionally used in astronomy for low-background imaging. While the ability to detect the presence of radiation (i.e. qualitative measurement) has been demonstrated at Sandia National Laboratories, there are several challenges in correlating images to known dose-fields (quantitative measurement). These challenges include: a low signal to background ratio, interferences due to electronic …

The "Double Standard" Of Nonproliferation: Regime Type And The U.S. Response To Nuclear Weapons Program, Alina Shymanska

International Journal of Nuclear Security

There is no doubt that the NPT regime is far from being equal for all states involved. As the predominant hegemonic power since WWII, the United States plays a major role in deciding the fates of non-great power proliferators. This article tries to find the logical explanation of the phenomenon whereby some nuclear proliferators are absolved regardless of their active accumulation of nuclear arsenals while others are labeled as “rogue states” and ordered to disarm. The article suggests that a particular proliferator’s political regime could affect the way in which its state is approached by the U.S., known for its …

Experimental Evaluation Of Uranyl Transport Into Mesoporous Silica Gel Using Fluorescence, Brandon M. Dodd

Theses and Dissertations

This research investigated parameters that can affect the use of nanoporous silica gel as a media for accumulating a detectable amount of uranium. The unique fluorescence of the Uranyl (UO₂²⁺) ion was used to evaluate the transport kinetics and accumulation within silica gel in a static fluid and under pressure driven flow. The addition of fluid flow decreased the time constant from on the order of an hour to approximately 2s with a very low fluid velocity of 0.36cm/s. The 0.36cm/s fluid velocity was found to be the critical velocity above which there was no gain in …

Neutronics Studies On The Nist Reactor Using The Ga Leu Fuel, Kyle A. Britton

Theses and Dissertations

The National Bureau of Standards Reactor (NBSR) located on the National Institute of Standards and Technology (NIST) Gaithersburg campus, is currently underway of fuel conversion from high enriched uranium (HEU) fuel to low enriched uranium (LEU) fuel. One particular challenging part of the conversion of the NBSR is the high average flux level (2.5×10¹⁴ n/cm²-s) required to maintain experimental testing capabilities of the reactor, without significant changes to the external structures of the reactor. Recently the General Atomics (GA) Training Research Isotopes General Atomics (TRIGA) fuel has shown some promising features as a LEU candidate for the …

Customized Multi-Group Cross Section Generation With Njoy For Discrete Ordinates Computed Tomography And Radiography Simulation, Steven Michael Wagstaff

Masters Theses

"The purpose of this work was to explore the creation of photoatomic multi-group cross section libraries to be used with a software package DOCTORS (Discrete Ordinates Computed TOmography and Radiography Simulator). This software solves the linear Boltzmann equation using the discrete ordinates method [1]. To create these libraries, NJOY2016 was used, creating both fine and broad energy multi-group cross section files. The cross section's accuracy was tested against an equivalent Monte Carlo simulation using MCNP6.

Two simulation geometries were used. The first, a cylindrical water phantom with a single source projection placed in front, simulating an X-ray radiography. The second …

Correlation Between Delay Time And Measured Concentration And Concentration Uncertainty By Neutron Activation Analysis, James Thomas Seman

Doctoral Dissertations

"For the last several decades, it has been apparent that new methods of identifying explosives can help investigators trace their origins. One way to identify an explosive is through the use of taggants: materials added to a product that encodes information about the product such as when it was manufactured.

This research investigates the survivability of a new identification taggant called the Nuclear Barcode that overcomes some of the downfalls that have been identified in prior taggants. The Nuclear Barcode encodes information as a unique combination of concentrations of rare earths (Ho, Eu, Sm, Lu, and Dy) and precious metals …

Design And Characterization Of Multi-Spectral Underwater Beam-Port For Pool-Type Research Reactors, Meshari Mesfer Alqahtani

Doctoral Dissertations

“The beam-port is a cardinal facility at research reactors necessary for dry irradiation, testing and measurement experiments. The Missouri University of Science and Technology Reactor (MSTR) is one such reactor with a beam-port. Installation of additional beam-port in such reactor facilities can be prohibitive. A novel remedy to this is an underwater beam-port for pool-type reactors. The design and characterization of a conceptual underwater multi-spectral beam-port for neutron and gamma fluxes were completed for the MSTR. The neutron spectra from the MSTR were simulated using the Monte Carlo N-particle (MCNP). The determined neutron spectra were experimentally validated using SAND-II. The …

Modulated Photothermal Radiometry: Detector Sensitivity Study And Experimental Setup, Jessica Nicole Seals

Masters Theses

"This thesis outlines the development of a system used for determining the surface thermal diffusivity of both non-irradiated and irradiated materials. The motivation for this work is to establish a modulated photothermal radiometry (PTR) system on the campus of Missouri University of Science and Technology. One of the main efforts described in this thesis is the design and construction of the physical apparatus. Along the way, it was necessary to perform a detailed sensitivity analysis of the system to determine whether the expected signal emitted from the sample falls within the bounds of detectivity for the HgCdTe (MCT) detector used …