The Future Of Nuclear Security In Moroccan Territory After The Creation Of The New Moroccan Agency Of Nuclear And Radiological Safety And Security: Opportunities And Challenges, 2017 Faculty of Sciences University Ibn Tofail
The Future Of Nuclear Security In Moroccan Territory After The Creation Of The New Moroccan Agency Of Nuclear And Radiological Safety And Security: Opportunities And Challenges, Amal Touarsi, Amina Kharchaf
International Journal of Nuclear Security
Nowadays, a security regime for protecting nuclear and radiological material—providing an intelligent national regulatory institution and establishing national security laws—is necessary in order for a state to ensure security of nuclear and radiological materials used within its borders.
This paper focuses on discussing the opportunities and challenges facing the future of nuclear security after the creation of the new Moroccan Agency of Nuclear and Radiological Safety and Security.
Determination Of Critical Experiment Correlations Via The Monte Carlo Sampling Technique, 2017 University of Tennessee, Knoxville
Determination Of Critical Experiment Correlations Via The Monte Carlo Sampling Technique, William Jay Marshall
Critical benchmark experiments are the foundation of validation of the computational codes used in criticality safety analyses because they provide a basis for comparison between the calculated results and the physical world. These experiments are often performed in series varying a limited number of parameters to isolate the effect of the independent parameter. The use of common materials, geometries, machines, procedures, detectors, or other shared features can create correlations among the resulting experiments. Most validation techniques used in criticality safety practice do not treat these correlations explicitly, and the effect of this is unclear as the correlations themselves are not ...
Scaled Experiment Investigating Sonomechanically Enhanced Inert Gas Sparging Mass Transfer, 2017 University of New Mexico
Scaled Experiment Investigating Sonomechanically Enhanced Inert Gas Sparging Mass Transfer, Floren Rubio, Leonard J. Bond, Edward Blandford
Aerospace Engineering Publications
One of the leading advanced reactor concepts is the fluoride salt high temperature reactor (FHR) currently under investigation. This design utilizes a fluoride molten salt, flibe (2 LiF/BeF2), as the primary coolant. One challenge of employing flibe as a coolant is the production and release of tritium. The FHR community is currently investigating various techniques to solve this tritium management challenge. One of the methods investigated is inert gas sparging which has been investigated during the Molten Salt Reactor Experiment (MSRE) in the 1960’s and 1970’s. To enhance the efficiency of this technique, high power ultrasonics can ...
Methodology For An Advanced Risk Assessment Of Crud Induced Power Shift Using Coupled Multi-Physics Simulations And A Monte Carlo Scenario Analysis Of The Potential Financial Benefits, 2017 University of Tennessee, Knoxville
Methodology For An Advanced Risk Assessment Of Crud Induced Power Shift Using Coupled Multi-Physics Simulations And A Monte Carlo Scenario Analysis Of The Potential Financial Benefits, Travis Louis Lange
Beginning in the 1970's, power uprates in nuclear power plants began to cause an operational problem called Crud Induced Power Shift (CIPS). Over decades, a method has been developed and refined that has allowed industry to effectively avoid CIPS. However, increasingly challenging economic environments have caused power plants to utilize more aggressive core designs. The problem of CIPS still looms over many reactors as a potential hazard requiring conservative measures. CIPS is due to complex physical and chemical interactions. Current industry methods use multiple single-physics simulations in their analyses. However, improved 3D multi-physics models of CIPS can provide a ...
Nestle To Origami Coupling: A Nuclear Non-Proliferation Tool For Lwr Fuel Assembly Isotope Analysis, 2017 University of Tennessee, Knoxville
Nestle To Origami Coupling: A Nuclear Non-Proliferation Tool For Lwr Fuel Assembly Isotope Analysis, Margaret Alva Kurtts
NESTLE to ORIGAMI coupling is a versatile nuclear modeling tool that allows researchers to directly observe the impact of operator induced changes on LWR assembly isotope production. The paper presents an experimental method by which to test the ability of an operator to manipulate the core neutron spectrum in order to produce higher quality plutonium for weapons use. The paper presents two plutonium production scenarios and evaluates their feasibility based on potential for detection and production capacity. Reactor modeling of a VVER-1000 uses NESTLE core simulation software. NESTLE outputs burnup and relative power information for all nodes in the core ...
Double Differential Neutron Yields Produced By Proton, Helium, And Iron Interactions In Thick Aluminum Targets, 2017 University of Tennessee, Knoxville
Double Differential Neutron Yields Produced By Proton, Helium, And Iron Interactions In Thick Aluminum Targets, Natalie Ann Mcgirl
Recent calculations of galactic cosmic ray (GCR) transport in enclosed, shielded space environments indicate that a minimum dose equivalent is achieved with aluminum shielding thicknesses near 20 g/cm2 [grams per centimeter squared]. Increases in the absorbed dose and dose equivalent with shielding thicknesses above 20 g/cm2 are believed to be caused by the production of light ions and neutrons in the thick shielding. However, uncertainties surround these calculations due to limited cross section and yield data for high-energy projectiles incident on thick targets. Thick-target neutron yields are particularly valuable measurements since they are produced over a ...
Determining 235u Enrichment Using A Dual-Energy Approach For Delayed Neutron Measurements, 2017 University of Tennessee, Knoxville
Determining 235u Enrichment Using A Dual-Energy Approach For Delayed Neutron Measurements, Angela Lynn Lousteau
Bulk uranium items are often measured using active neutron interrogation systems to take advantage of the relatively high penetrability of neutrons, providing the ability to quickly and accurately measure uranium masses in large, dense configurations. Active techniques employ an external neutron source to induce fission in the uranium and subsequently measure emitted prompt fission or delayed neutrons. Unfortunately, the emitted neutrons from 235U [uranium-235] and 238U [uranium-238] are, for all practical purposes, indistinguishable; therefore, commonly used systems such as the Active Well Coincidence Counter, the 252Cf [californium-252] Shuffler, and other systems based on measurement of prompt or ...
Novel Fission Track Detection For Identification And Characterization Of Special Nuclear Materials, 2017 University of Tennessee, Knoxville
Novel Fission Track Detection For Identification And Characterization Of Special Nuclear Materials, Jonathan Allen Gill
Fission track detection and analysis is used primarily in nuclear safeguards to identify special nuclear material. Identification of isotopic ratios is a crucial step in understanding the intended use of nuclear material and the nature of the materials production cycle. Unfortunately, this methodology uses etchable track detectors that require significant expertise and intensive labor to process.
This study developed a novel method using lithium fluoride (LiF) as a fluorescing nuclear track detector to conduct fission track analysis for isotopic prediction of uranium enrichment. Individual latent tracks produced by fission products were observed in LiF for the first time. These tracks ...
Improvements To Nestle: Cross Section Interpolation And N-Group Extension, 2017 University of Tennessee, Knoxville
Improvements To Nestle: Cross Section Interpolation And N-Group Extension, William Matthews Kirkland
The NESTLE program is a few-group neutron diffusion reactor core simulator code utilizing the nodal expansion method (NEM). This thesis presents two improvements made to NESTLE regarding cross-section interpolation and multigroup capability.
To quickly and accurately obtain cross sections from lattice physics input data, a new cross section interpolation routine was developed utilizing multidimensional radial basis function interpolation, also known as thin plate spline interpolation. Testing showed that, for existing NESTLE lattice physics input, accuracy was retained but not improved and processing time was longer. However, the new interpolation routine was shown allow much greater exibility in the case matrix ...
The Development Of Cesium Calcium Bromo-Iodide Scintillator For X-Ray And Gamma Ray Detection, 2017 University of Tennessee, Knoxville
The Development Of Cesium Calcium Bromo-Iodide Scintillator For X-Ray And Gamma Ray Detection, Matthew Starr Loyd
CsCaI3:Eu [cesium calcium iodide doped with europium] is a promising scintillator material that can be grown from the melt, but undergoes a tetragonal to orthorhombic phase transition upon cooling at 255 °C [degrees Celsius], causing twinning and cloudiness. The purpose of this work is to suppress this solid to solid phase transition in the CsCaI3:Eu scintillator, which has a light yield of ~40000 ph/Mev and energy resolution at 662keV of ~4%, by halide replacement to form the compound CsCaBrxI3-x:Eu [cesium calcium bromo-iodide doped with europium]. Crystals 8 cm3 [cubic centimeters ...
Modeling Of Dislocation Channel Formation And Evolution In Irradiated Metals, 2017 University of Tennessee, Knoxville
Modeling Of Dislocation Channel Formation And Evolution In Irradiated Metals, Peter James Doyle
Defect-free dislocation channel formation has been reported to promote plastic instability during tensile testing via localized plastic flow, leading to a distinct loss of ductility and strain hardening in many low-temperature irradiated materials. In order to study the underlying mechanisms governing dislocation channel width and formation, the channel formation process is modeled via a simple stochastic dislocation-jog process dependent upon grain size, defect cluster density, and defect size. Dislocations traverse a field of defect clusters and jog stochastically upon defect interaction, forming channels of low defect-density. Based upon prior molecular dynamics (MD) simulations and in-situ experimental transmission electron microscopy (TEM ...
Positron Emission Particle Tracking Software Maturation Project, 2017 University of Tennessee, Knoxville
Positron Emission Particle Tracking Software Maturation Project, Eric Michael Moore
Positron Emission Particle Tracking (PEPT) software at the University of Tennessee (MultiPEPT) has demonstrated promising performance in multiple measurement domains. In order to contribute to its further development, a full codebase audit and three focused performance assessments were undertaken. Several improvements were made to the codebase as a result of the audit. The assessments demonstrated a linear axial detector- MultiPEPT response, the effect of mesh size variation, and the effect of temporal overlap variation. A number of best practices are compiled for effective use of MultiPEPT.
Solar System Battery Backups For Reactor Coolant Pumps During Electricity Outages Resulting From Natural Disasters, Md. Shamsul Huda Sohel
International Journal of Nuclear Security
In a nuclear power plant, its coolant system is major safety equipment. Coolant system failure causes several accidents in nuclear history. There are so many causes for coolant system failure. One of them is lack of electric power for coolant pumps. In typically NPP there is backup system for power redundancy. In this article, focus on reactor coolant system and its backup power when main grid lines failure. Here discuss about solar backup power for batteries and increases a safety lines for reactor coolant pumps. So, our main goal is providing a battery backup from reliable natural source and ensuring ...
The Inverse Kinetics Method And Its Application To The Annular Core Research Reactor, 2017 University of New Mexico
The Inverse Kinetics Method And Its Application To The Annular Core Research Reactor, Thomas A. Ball
Nuclear Engineering ETDs
The inverse kinetics method, is a method to calculate a reactor’s reactivity profile from its power profile. In this thesis, the reactivity profile corresponding to pulse operations of the Annular Core Research Reactor (ACRR) was sought. Of specific interest was the shutdown reactivity of the reactor following the pulse. This required accounting for delayed beryllium photoneutrons that are present in the ACRR in addition to U-235 delayed neutron precursors. The power profiles of the pulses were experimentally measured using a diamond photoconductive detector (PCD). Using the inverse kinetics equation, a computer code was written to numerically calculate the reactivity ...
Evaluation Of Energy Released From Nuclear Criticality Excursions In Process Solutions, 2017 University of New Mexico
Evaluation Of Energy Released From Nuclear Criticality Excursions In Process Solutions, Corey Michael Skinner
Nuclear Engineering ETDs
Typically, the staff of a nonreactor nuclear facility or a processing facility involving nuclear material are not expected to have a strong technical background in nuclear criticality physics, as that is not the purpose of these sites, yet handle material with the potential to undergo a criticality excursion. Such excursions have occurred 22 times in the past, 21 of which involved an aqueous solution material. Therefore, it would be useful to have a general model capable of providing a quick estimation of the consequences of a criticality excursion in a processing plant. To this end, correlations developed utilizing experimental data ...
Gamma-Radiation Induced Corrosion Of Alloy 800, 2017 The University of Western Ontario
Gamma-Radiation Induced Corrosion Of Alloy 800, Mojtaba Momeni
Electronic Thesis and Dissertation Repository
This thesis presents a newly developed mechanism and predictive model for the corrosion of Alloy 800. The Fe-Cr-Ni Alloy (Incoloy 800) is mainly used for steam generator (SG) tubing in CANDU and PWR reactors and is a candidate material for the proposed Canadian Supercritical Water Reactor (SCWR) in which it will be exposed to extreme conditions of high radiation flux and large temperature gradients. The influence of gamma radiation and water chemistry conditions on the corrosion behaviour of Alloy 800 are studied in this work. Ionizing radiation creates reducing (•eaq–, •H, •O2-) and oxidizing radiolysis (•OH, H2 ...
Time-Of-Flight And Energy Loss Analysis On The Unm Fission Fragment Spectrometer, 2017 University of New Mexico
Time-Of-Flight And Energy Loss Analysis On The Unm Fission Fragment Spectrometer, Shelby Fellows
Nuclear Engineering ETDs
The University of New Mexico spectrometer experimental work has been used to provide an event-by-event fission product measurement to aid in filling in the gaps in existing fission product yield data, as part of the Los Alamos National Lab Spectrometer for Ion Detection in Fission Research project (SPIDER) collaboration. This thesis examines the time-of-flight (TOF) component of the spectrometer towards improving the resolution of the system. Different thicknesses of TOF conversion foils were examined with alpha particles and fission fragments: 20, 55, and 100 µg/cm2 carbon foils. For the thinnest carbon foil studied, a timing resolution of 160 ...
Asymptotic Neutronic Solutions For Fast Burst Reactor Design, 2017 University of New Mexico
Asymptotic Neutronic Solutions For Fast Burst Reactor Design, Edward L. Hobbs
Nuclear Engineering ETDs
Deterministic numerical methodologies for solving time-eigenvalue problems are valuable in characterizing the inherent rapid transient neutron behavior of a Fast Burst Reactor (FBR). New nonlinear solution techniques used to solve eigenvalue problems show great promise in modeling the neutronics of reactors. This research utilizes nonlinear solution techniques to solve for the dominant time-eigenvalue associated with the asymptotic (exponential) solution to the neutron diffusion and even-parity form of the neutron transport equation, and lays the foundation for coupling with other physics phenomena associated with FBRs.
High security costs and proliferation risks associated with Highly Enriched Uranium (HEU) fueled FBRs are the ...
Nuclear Fusion As A Primary Energy Production Method, 2017 Missouri University of Science and Technology
Nuclear Fusion As A Primary Energy Production Method, Joshua Eiswirth
Missouri S&T’s Peer to Peer
In this paper, the possibility of using nuclear fusion as a primary energy producer will be analyzed. A brief overview of nuclear fusion is given as well as the drawbacks of nuclear fusion today. The human species, need to find a more abundant and renewable means to produce energy, because the non-renewable resources relied on today will be completely used up in as little a 100 years. Nuclear fusion, if perfected, offers a reliable and extremely abundant energy source. With commercial nuclear fusion plants more energy would be available than ever before. While no efficient fusion reactor design exists today ...
Sensitivity Analysis For Best-Estimate Thermal Models Of Vertical Dry Cask Storage Systems, 2017 University of Tennessee, Knoxville
Sensitivity Analysis For Best-Estimate Thermal Models Of Vertical Dry Cask Storage Systems, Remy R. Devoe, Kevin R. Robb, Steven Skutnik
Faculty Publications and Other Works -- Nuclear Engineering
Loading requirements for dry cask storage of spent nuclear fuel are driven primarily by decay heat capacity limitations, which themselves are determined through recommended limits on peak cladding temperature within the cask. This study examines the relative sensitivity of peak material temperatures within the cask to parameters that influence both the stored fuel residual decay heat as well as heat removal mechanisms. These parameters include the detailed reactor operating history parameters (e.g., soluble boron concentrations and the presence of burnable poisons) as well as factors that influence heat removal, including non-dominant processes (such as conduction from the fuel basket ...