Nuclear Engineering Commons^™

Design And Characterization Of Systems For Direct Spatial Imaging Of Low-Energy Gamma-Radiation Sources, Phoenix Baldez

Nuclear Engineering ETDs

This work describes the development of radiation detection systems to identify and image special nuclear material (SNM) using low energy gamma rays. The imaging of these materials is crucial for timely, in the field responses to potential threats to national security. Using a spectroscopy system, the sources can be identified while images can be produced concurrently for the sources which are present. Two systems were designed and characterized in this study, a collimated imager which used collimation in front of a small CdTe detector, and a pixelated pinhole imager, using a pinhole mask in front of a pixelated CZT detector. …

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 …

Patient Specific Radiation Doses From Projection Radiography Images: Improving The Accuracy Of Low Dose Radiation Calculations, Daniel J. Sandoval

Nuclear Engineering ETDs

Due to an increase in regulatory scrutiny and medical facility accreditation requirements to monitor patient radiation dose from diagnostic imaging procedures, there is a growing necessity to determine and record accurate patient radiation dose from diagnostic medical imaging procedures. Current methods of patient dosimetry in diagnostic imaging are both extremely difficult and time consuming, require large computing resources (such as Monte Carlo computations), or lack accuracy due to using data based on homogeneous materials and “standard-man sized” anthropomorphic models.

This dissertation provides an algorithm that calculates a more accurate dose using patient-specific projection radiographic images. The algorithm includes measurements acquired …

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 …

Case Study On The Development Of Engineering Design Modification Projects For U.S. Nuclear Power Plants: A Knowledge Retention Tool In Support Of The Longevity And Resilience Of The Nuclear Power Industry, Pamela M. Torres-Jiménez

Engineering Management & Systems Engineering Theses & Dissertations

The nuclear power industry in the United States (U.S.) has gone through various changes throughout its history. Most recently, plans to grow the industry through the construction of new power plants have ceased. Because of this, the industry is at a period where the longevity and resilience of existing nuclear power plants are vital to its subsistence.

One of the ways existing nuclear power plants can assure longevity and resilience is by performing engineering design modifications efficiently and at a lower cost. Strategic plans, such as the Delivering the Nuclear Promise, can support nuclear utilities to achieve this. Another strategy …

Development Of A Novel Framework For The Application Of Signature Based Safeguards (Sbs) To Pyroprocessing, Philip Leo Lafreniere

Nuclear Engineering ETDs

Traditional nuclear material accountancy (NMA) faces several challenges when applied to pyroprocessing facilities. To address these challenges, alternative methods of safeguarding nuclear material are being developed. One method is process monitoring (PM). PM involves taking operational process data and applying it to safeguards using an advanced framework. Signature Based Safeguards (SBS), a proposed PM framework, involves the identification of anomalous scenarios and the subsequent identification and detection of their respective PM signatures from a system of measurements. SBS has previously focused on failure modes that result in transfer of mass to unexpected places in the mass flowsheet. This work developed …

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 …

The U.S. Nuclear Waste Impasse: Transportation Implications, Robin M. Rotman, Michael F. Mcbride

Faculty Publications

For several years there has been an impasse, in the political branches, over how to make progress on dealing with the intractable problem of nuclear waste disposal in the United States. Currently, over 120 sites, spread across 39 states, host commercial spent fuel—many of these sites are former reactors that have become de facto interim nuclear waste storage sites, pending a permanent solution. Transportation considerations are central in this discussion. With the potential for Congress to make progress on this issue following the 2018 midterm elections, this article reviews the potential paths forward and considers possible implications for the transportation …

Innovative Fuel Design To Improve Proliferation Management, Taylor C. Britt

Theses and Dissertations

This research uses an existing innovative fuel design (IFD) that has intrinsic safety features and enhanced economics over the current uranium dioxide (UO₂) light water fuel design and evaluates promising methods to improve the waste management and proliferation resistance of the IFD by doping the fresh fuel with select actinides.The most robust approach for proliferation resistance is to denature these materials by adding a uranium or plutonium isotope that hampers the usability of the materials in weapons. The proposed modifications to the IFD use this approach through elevated fractions of ²³⁸Pu. ²³⁸Pu generates large quantities of …

การผลิตไบโอดีเซลจากน้ำมันพืชใช้แล้วโดยใช้เครื่องไดอิเล็คทริคแบร์ริเออร์ดิสชาร์ตพลาสมาแบบหัวฉีดละออง, กุลนันทน์ ภูประสิทธิ์

Chulalongkorn University Theses and Dissertations (Chula ETD)

ได้ศึกษาผลิตไบโอดีเซลจากน้ำมันพืชใช้แล้วโดยใช้เครื่องปฏิกรณ์ไดอิเล็คทริคแบร์ริเออร์ดิสชาร์ตพลาสมาแบบหัวฉีดละออง โดยทำการแบ่งการศึกษาออกเป็นสองส่วน ส่วนแรกเป็นการสร้างระบบจ่ายไฟเพื่อก่อให้เกิดพลาสมา โดยสามารถจ่ายแรงดันไฟฟ้าได้สูงถึง 15 kV จ่ายกระแสไฟฟ้าได้สูงถึง 100 mA และปรับความถี่ได้ในช่วง 20 - 20,000 Hz โดยระบบประกอบด้วยเครื่องกำเนิดสัญญาณ (Signal generator), เครื่องขยายสัญญาณ (Signal amplifier), หม้อแปลงขึ้น (Step-up transformer) และหม้อแปลงนีออนไลท์ (Neon sign transformer) 5 ตัวต่อขนานกัน ซึ่งระบบจ่ายไฟที่สร้างขึ้นนี้จะสามารถก่อให้เกิดพลาสมาที่ความดันบรรยากาศ และส่วนที่สองเป็นการศึกษาการนำระบบจ่ายไฟที่สร้างขึ้นเพื่อก่อให้เกิดพลาสมาแบบไดอิเล็คทริค โดยนำมาทำปฏิกิริยาทรานส์เอสเทอริฟิเคชัน (Transesterification) โดยปรับอัตราส่วน เมทานอล:น้ำมันพืช ให้อยู่ในช่วง 3:1 - 10:1 โดยโมล ใช้น้ำมันพืช 100 ml ที่อุณหภูมิห้อง ทำการหมุนเวียนระบบด้วยปั๊มรีดท่อ (Peristaltic pump) ระยะห่างระหว่างขั้วแคโทด (Cathode) และแอโนด (Anode) 3 มิลลิเมตร และฉีดพ่นสารผสมโดยใช้หัวฉีดละออง (Atomizing nozzle) เป็นเวลา 2 ชั่วโมงพบว่าค่าผลผลิตไบโอดีเซล (Biodiesel yield) น้อยกว่า 1 % ของทั้ง 3 อัตราส่วน คืออัตราส่วน 3:1, 6:1 และ 10:1 ต่อโมล อีกทั้งไม่เกิดกลีเซอรอลในระบบ เนื่องจากสารผสมเมื่อสัมผัสกับแผ่นขนานระหว่างขั้วจะประพฤติตัวเป็นฉนวนทำให้พลาสมาที่เกิดขึ้นมีปริมาณน้อยลงจึงทำให้ปฏิกิริยาเกิดขึ้นได้น้อย แต่ระบบจ่ายไฟที่สร้างขึ้นนี้สามารถก่อให้เกิดพลาสมาได้จริง

The Rhetoric Of Science Education And Technology, Iwasan D. Kejawa

School of Computing: Faculty Publications

Nearly thousands of science experiments are performed both on humans and animals every year in the United States (Gregory, 1999). Does Science enormously play a role in the well-beings of individual in the society? Research has found that science education is through motivation and satisfying the needs of humans. The scientific world is part of an elongated human development. This can be substantiated with the use and evolution of TECHNOLOGY and SCIENCE (Minton, 2004). Education of the entities that comprise the need to achieve the goal of TECHNOLOGY and SCIENCE which are important issues of today. Research has shown that …

Synthesis Of High Efficiency Amidoxime Polymer Adsorbents For Uranium Extraction From Seawater By Radiation-Induced Polymerization, Wijittra Wongjaikham

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study synthesized amidoxime polymer gel for uranium extraction from seawater through a polymerization process with gamma ray or UV-C radiation. The synthesis started with a mixture of acrylonitrile (AN) and methacrylic acid (MAA) monomers together with methylene bisacrylamide as a crosslinker and hydrogen peroxide in the case of UV radiation. The mixture was irradiated with gamma ray at various doses or UV-C for various durations. The resulting polymer gel was ground into fine particles and immersed in a hydroxylamine hydrochloride solution for 90 minutes in order to convert the chemical functional group from the cyano group into the amidoxime …

การพัฒนาเทคนิคเอกซเรย์คอมพิวเตดโทโมกราฟีโดยการบันทึกภาพบนฉากเรืองรังสีด้วยกล้องดิจิตอล, พณพณ สาวิโรจน์

Chulalongkorn University Theses and Dissertations (Chula ETD)

งานวิจัยนี้มีจุดประสงค์ในการพัฒนาระบบถ่ายภาพด้วยรังสีเอกซ์โดยใช้ฉากเรืองรังสีและพัฒนาเทคนิคการสร้างภาพโทโมกราฟีของชิ้นงาน ระบบบันทึกภาพประกอบด้วยฉากเรืองรังสี กล้องถ่ายภาพดิจิตอล และแท่นวางชิ้นงานที่หมุนได้ การหมุนของแท่นวางชิ้นงานถูกควบคุมโดยสเตปปิงมอเตอร์และซอฟต์แวร์ที่เขียนด้วย Visual basic 6.0 ในขณะที่การตั้งค่าและการถ่ายภาพของกล้องถ่ายภาพดิจิตอลถูกควบคุมด้วยคอมพิวเตอร์ผ่านทางสายยูเอสบี ได้ทำการศึกษาผลของการตั้งค่าต่างๆ ของกล้องถ่ายภาพและของเครื่องกำเนิดรังสีเอกซ์ที่มีต่อคุณภาพของภาพที่ได้ จากนั้นได้ทดสอบชิ้นงาน 6 ชิ้นที่มีองค์ประกอบและลักษณะต่างกัน โดยทำการถ่ายภาพแต่ละชิ้นงานทุกๆ 1.8 องศา รวมทั้งหมด 100 ภาพ เมื่อนำไปสร้างภาพซีทีแล้วพบว่ามีคุณภาพน่าพอใจมาก เวลาที่ใช้ในการถ่ายภาพ และสร้างภาพแต่ละตัวอย่างรวมทั้งสิ้นประมาณ 7 นาที อย่างไรก็ตามสำหรับตัวอย่างที่มีความหนามากและมีความหนาแน่นสูงอาจต้องปรับเปลี่ยนไปขึ้นอยู่กับการตั้งค่าของกล้องถ่ายภาพและของเครื่องกำเนิดรังสีเอกซ์ รวมทั้งชนิดของฉากเรืองรังสี งานวิจัยนี้ชี้ให้เห็นการนำระบบและเทคนิคที่พัฒนาขึ้นไปใช้งานในการตรวจสอบชิ้นงานในอนาคต

Lanthanide-Based Core-Shell Nanoparticles As Multifunctional Platforms For Targeted Radionuclide Therapy And Multimodal Molecular Imaging, Miguel Toro-Gonzalez

Theses and Dissertations

Lanthanide phosphate (LnPO₄) and lanthanide vanadate (LnVO₄) nanoparticles (NPs) are promising platforms for theranostic applications because of their chemical stability, low solubility, low toxicity, and unique luminescence and magnetic properties. Motivated by the high radiation resistance and ability to host actinides of naturally occurring lanthanide-based compounds, LnPO₄ and LnVO₄ NPs were studied as radionuclide carriers for targeted radionuclide therapy using in vivoα-generators, ²²³Ra, ²²⁵Ac, and ²²⁷Th. The implementation of these radionuclides has shown potential for the treatment of micrometastases and solid tumors as well as challenges in the retention of …

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 …

Development And Monte Carlo Validation Of A Finite Element Reactor Analysis Framework, Wayne J. Brewster

Masters Theses

"This study presents the development and Monte Carlo validation of a continuous Galerkin finite element reactor analysis framework. In its current state, the framework acts as an interface between the mesh preparation software GMSH and the sparse linear solvers in MATLAB, for the discretization and approximation of 1-D, 2-D, and 3-D linear partial differential equations. Validity of the framework is assessed from the following two benchmarking activities: the 2-D IAEA PWR benchmark; and the 2-D Missouri Science and Technology Reactor benchmark proposed within this study. The 2-D IAEA PWR multi-group diffusion benchmark is conducted with the following discretization schemes: linear, …

An Investigation Into The Effects Of Ion Tracks On Α-Quartz, Bryant Alan Kanies

Masters Theses

"The passage of a swift heavy ion through a material can cause columnar, amorphous nano-structures known as ion tracks. Swift heavy ions are present in a number of applications ranging from nuclear reactors to nuclear waste storage and onboard spacecraft. The study of ion tracks has been ongoing since the late 1950s and has led to several technological advancements. In fact, ion beams have been used to enhance material properties and aid in the production of electrical components. Ion beams, and their resultant ion tracks, can therefore be seen as a method to purposefully alter material properties such as thermal …

Investigation Of The Hydrodynamics And Scale-Up Of Advanced Triso Nuclear Fuel Manufacturing Using Sophisticated Measurement Techniques, Thaar M. Aljuwaya

Doctoral Dissertations

"The successful performance and safety of the Very-High-Temperature Nuclear Reactors (VHTR) extremely depend on the quality of the TRISO nuclear fuel coated particles. However, the coating of the TRISO particles is delicate process and impacted by the hydrodynamics of spouted beds. Therefore, in this work, we applied advanced non-invasive measurement techniques which are gamma-ray computed tomography (CT) and radioactive particle tracking (RPT), to investigate foremost the local parameters to advance the fundamental understanding of the hydrodynamics and scale-up of gas-solid spouted beds. The CT technique has been applied to study the effects of particle density, particle size, bed size, and …

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 …

Advancement In Thermal Energy Storage Using Phase Change Materials, Rami Mohammad Reda Saeed

Doctoral Dissertations

"The dissertation is intended to study the fundamental physical behavior of phase change materials (PCMs) and provide a comprehensive overview of the state of the art in their design and applications for thermal energy storage. Standard, predictive and thermodynamic models were presented to develop new PCM eutectic mixtures in a more scientific design approach. As new eutectic PCMs were developed, further research efforts were initiated to develop functionalized PCMs with enhanced thermal and physical properties to create the next generation of PCMs. Further efforts have been expanded to review several high-temperature PCM candidates with phase transition temperatures in the range …