Physics Commons^™

Explore The Six Fundamentals Unlv Accelerated: High-Energy X-Ray Applications (Hexa), Oliver A. Hemmers

NSTec UNLV Symposium

• UNLV and HEXA for a Brighter Southern Nevada Future
• History of HEXA’s Public-­‐Private Partnership
• Discovery Through Research and Innova4ve Technologies
• The Innova4ve Process
• Southern Nevada Research and Economic Development Applica4ons
• HEXA Program Benefits

Current Issues: Doe's Nuclear Energy Programs, Peter Lyons

NSTec UNLV Symposium

• Secretary Moniz on Nuclear Energy
• Secretary Moniz Announces $6.5 Billion Vogtle Loan Guarantee
• Role of U.S. Department of Energy for Sustainable and Innovative Nuclear Energy
• Overview
• Why is the U.S. Government Interested in Supporting SMR Technologies?
• DOE Program to Support SMR Design Certification & Licensing
• Status of SMR Licensing Technical Support Program
• Blue Ribbon Commission Recommendations
• Administration Strategy for Used Fuel Management
• Congressional Activity
• Uranium Extraction from Seawater
• Supercritical CO₂ Energy Conversion
• HUBS AND NEAMS – PARTNERSHIP AND COMPLEMENTARITY
• Nuclear Energy Enabling Technologies Nuclear Energy Advanced Modeling & Simulation (NEAMS)
• NE Modeling and Simulation Energy Innovation Hub Highlights
• Nuclear …

The Unlv Xps Facility – Research Opportunities, Allen L. Johnson

NSTec UNLV Symposium

XPS Outline

•XPS – what is it?

•How is it done?

•What are its limitations?

•Future direction – radioactive samples

–Sample containment and transport
–Sputter controls
–Radiation limits

•Summary

Development Of Ion Beam Nuclear Transmutation Doping (Ibntd) For Novel Electronics In Extreme Conditions, Michael G. Pravica, Noel A. Guardala, Jack L. Price

NSTec UNLV Symposium

Development of IBNTD for electronics under extreme conditions.

•We hope to create novel wide bandgap devices using Ion Beam Nuclear Transmutation Doping (IBNTD). These devices may be used as rugged high power switches, and high current/low noise amplifiers. Diamond in itself represents a “Holy Grail” for electrical applications due to its very high thermal conductivity and excellent electrical characteristics.
•We also hope to develop devices that can convert the enormous energy from high-energy nuclear particles (α2+,β-,β+, γparticles) into useful electricity and thus harness the enormous energy still contained in “spent” nuclear fuel. Developing these direct energy conversion (DEC) devices would …

Overview Of Nstec Plasma Focus Tubes And Magnetohydrodynamic Modeling Capabilities, Tim Meehan

NSTec UNLV Symposium

•Brief Description of how DPFs work, in general what they are useful for.
•DPF devices that we have at NSTec
•Using MHD modeling software to optimize designs and predict performance
•Neutron Resonance Spectroscopy

Pmts And Radiation/Particle Detection Technologies, Brent Davis

NSTec UNLV Symposium

Describes technical standards for equipment in the field of Nuclear and Optical Physics.

National Center For Nuclear Security, Veraun Chipman, Amanda Klingensmith, Cathy Snelson

NSTec UNLV Symposium

National Center for Nuclear Security (NCNS) Mission

•Chartered mission is to enhance the Nation’s verification and detection capabilities in support of nuclear arms control and nonproliferation through R&D activities at the NNSS
•Three focus areas
–Treaty Verification Technologies
–Nonproliferation Technologies
–Technical Nuclear Forensics

High Pressure Structural Studies On Nb5si3 Up To 26.2 Gpa, Brandon Stewart, Ravhi S. Kumar

Undergraduate Research Opportunities Program (UROP)

With the use of synchrotron techniques, we can better understand how crystalline structures behave under extreme conditions. This yields the opportunity to resolve complex crystal structures [1]. Here, we focus on the high pressure crystal structure of Nb5Si3. Refractory metal silicides are an important class of materials as they are used in high temperature applications such as turbines and aerospace modules. As an example, the performance of a jet engine is highly influenced by the maximum internal pressure and temperature possible. Obtaining higher levels of thrust is dependent upon the material's ability to remain structurally sound under extreme temperatures and …

High Pressure Study Of 1,1-Diamino-2,2-Dinitroethene With Raman Spectroscopy, Jack Brangham, Michael Pravica, Martin Galley

Undergraduate Research Opportunities Program (UROP)

The goal of this experiment is to better understand the reasons for Fox-7s insensitivity and high performance. It is very similar to other explosives in composition but different in structure. This different structure is believed to be the reason for Fox-7s unique characteristics. Using Raman spectroscopy along with high pressure techniques we hope to better understand this molecule and how it handles extreme conditions.

Ionic Alkalihalides As Pressure Media In Dac Experiments, Julius Monello

Undergraduate Research Opportunities Program (UROP)

In Diamond Anvil Cells (DACs), usually a pressure transmitting medium functions to transform the uniaxial pressure supplied by the opposing diamond anvils into uniform hydrostatic pressure acting on the sample. Conventionally, a 4-1 methanol-ethanol solution, or a 16-3-1 methanol-ethanol-water solution is used as pressure transmitting medium. However, these two solutions transform into a glass with high elastic shear strength at pressures around 12-14 GPa and no longer function as hydrostatic medium. Our goal was to determine if liquid ionic alkalihalide alkanolate complexes will provide more uniform pressure in the cell up to 20 GPa. Ruby (Cr-doped AlP,) produces two Cr"+ …

Neutron Diffraction Of Nabd4: Phase Transition, Rietveld Structure Refinements, And Equation Of State, Guillermo Esparza, Esparza, Patricia Kalita, Andrew Cornelius

Undergraduate Research Opportunities Program (UROP)

NaBH4 is a hydride with possible applications as a hydrogen storage material for future renewable energy technologies. It’s dehydrogenation properties are enhanced with the mixture of particular catalysts through ball-milling techniques during which local pressures may exceed several GPa’s. It is for this reason that understanding the behavior of pressure induced phase changes of its crystalline unit cell is an area of interest.

Second Hyperpolarizability Of Carbon Tetrachloride, Phillip C. Lotshaw, Anna M. Smith, David P. Shelton

Undergraduate Research Opportunities Program (UROP)

Although present theories of nonlinear optics agree with observed behavior in simple atoms such as helium, more complex molecules containing many electrons, such as carbon tetrachloride (CCI4), cannot consistently be described by theory. Through experimental analysis of nonlinear materials, a new, more sophisticated model for describing their properties could be realized. The purpose of our experiment was to measure the nonlinear behavior of the second harmonic signal generated from CCI4 and to compare the results with the prediction by the CCSD(T) molecular model.

Crystal Structural Behavior Of Cocu₂O₃ At High Temperatures, April Jeffries, Ravhi S. Kumar, Andrew L. Cornelius

Undergraduate Research Opportunities Program (UROP)

High temperature structure of CoCu₂O₃ The spin ladder compounds have received much attention recently due to their relation to the high transition temperature superconductivity. Also the study of spin ladder compounds is of great interest to explore the specific characteristics that result in their behavior. The CoCu₂O₃ spin ladder crystal structure is similar to SrCu₂O₃, which is apparent composition for many high temperature superconductors. The effects of temperature on structural change are investigated for this system. High temperature x-ray diffraction patterns were collected up to 1000⁰C and the variation of lattice parameters as a function of temperature up to decomposition …

High Pressure Structural Studies On Baco3 Up To 20 Gpa, Justine Carryer, Ravhi S. Kumar

Undergraduate Research Opportunities Program (UROP)

Carbonate compounds are thought to make up a minor portion of the Earth's upper mantel. Shock heating of the surfaces of carbonate rocks, as in the instance of a meteor impact, has the potential to affect CO2 concentrations in the Earth's atmosphere. The bulkmodulus of carbonate materials is directly proportional to the rate of devolatilization under these conditions [1]. The interest in Barium Carbonate (BaCO3) specifically is motivated by its structural proximity to aragonite carbonates. Crystalline phase transitions occur in aragonite under extreme conditions that are difficult to maintain in a laboratory; BaC03 is isostructural with aragonite and therefore is …

Investigation Of Raman Active Modes Of Mgxzn1-Xcr2o4, Nichollas Macholl, Tyler Mosher

Undergraduate Research Opportunities Program (UROP)

Using Raman spectroscopy, vibrational modes of the spinel structure MgxZn1-xCr2O4 were experimentally examined. The spinel compounds were synthesized by producing solid solutions via combustion method, of MgxZn1-xCr2O4 in the range x=0 to x=1 in 0.1 intervals. The purpose of which was to experimentally verify gradual shifts of Raman peaks as the samples transitioned between the two different compounds and gain information about the dependencies of the lattice vibrations on the tetrahedral and octahedral cations. X-ray diffraction was also used to verify spinel structure, and track the changes in lattice parameter of the samples.

Structure Studies On Lanthanide Technetium Pyrochlores As Prospective Host Phases To Immobilize 99- Technetium And Fission Lanthanides From Effluents Of Reprocessed Used Nuclear Fuels, Thomas Hartmann, Ariana Alaniz

Festival of Communities: UG Symposium (Posters)

We performed a systematic investigation of the incorporation of 99Tc into pyrochlore oxide structures, Ln2Tc2O7, where Ln represents trivalent lanthanide Ln3+ cations, while 99Tc is atetravalent, Tc4+, metal cation. Pyrochlore compounds are high-melting temperature oxides and are recognized for their durability. Our goal in this preliminary study is to characterize and quantify the range of stability of the lanthanum technetium pyrochlore oxide phase. Hereby, powder X-ray diffraction (XRD) and Rietveld analysis were used to determine and characterize the crystalline phase content with high accuracy, and scanning electron microscopy (SEM) was used to characterize the microstructure and homogeneity of the synthesized …

Entangling The Lattice Clock With Rydberg Gates, Frank J. Greenhalgh

Festival of Communities: UG Symposium (Posters)

Knowledge of the exact time is critical to many engineers and planetary experts; unfortunately atomic clocks can't have infinite accuracy by Heisenberg's uncertainty principle. To attain accuracy past the limit we have achieved today, we will design a critical improvement of the atomic clock via the Rydberg gates method. Rydberg gates synchronize the atomic states so that they are more sensitive which will greatly increase the accuracy. This project will introduce fast acting Rydberg gates to an existing atomic clock layout. The Rydberg gates will allow the clock to entangle atoms in less time, thus decreasing decoherence effects on the …

Oral Presentation: Next Generation Nuclear Fuels, Douglas Hanks

Festival of Communities: UG Symposium (Posters)

Zirconium carbide has been proposed as a coating layer for next generation (“TRISO”) nuclear fuel, and is intended as a diffusion barrier to contain fission products (e.g., Pd). To study the chemical interaction between Pd and ZrC, their interface was investigated using X-ray Photoelectron Spectroscopy (XPS). Pd was step-wise deposited onto ZrC in ultra-high vacuum, and the chemical interaction at the interface was monitored, also as a function of temperature (up to 1000 C). In the presentation, details of the chemical interaction and changes in the chemical environment of Pd and their relevance for TRISO fuel will be discussed.

Aspect Ratio Dependent Buckling Mode Transition In Single-Walled Carbon Nanotubes Under Compression, Jeremy Feliciano

Festival of Communities: UG Symposium (Posters)

Using molecular dynamics simulations, we study axial compressive behavior of single-walled carbon nanotubes (SWCNTs) with a wide range of aspect ratios (length to diameter ratio). It is shown that the difference in aspect ratio leads to distinct buckling modes in SWCNTs. Small-aspect-ratio SWCNTs primarily exhibit shell buckling; they switch to column buckling mode with increasing aspect ratio. Further compression of the already column buckled large-aspect-ratio SWCNTs results in a shell buckling. This shell buckling mode is distinct from that of small-aspect-ratio SWCNTs in that it originates from the column buckling induced bending deformation.

Elastic Plastic Self Consistent (Epsc) Modeling Of Plastic Deformation In Fayalite Olivine, Christopher J. Cline Ii, Pamela Burnley

Festival of Communities: UG Symposium (Posters)

We are using an Elastic Plastic Self Consistent Model (a type of numerical simulation) to study deformation of olivine. Olivine is one of the major constituents of the Earth’s upper mantle and its deformation properties have an important influence on how the Earth’s crust deforms. For example, the flow strength of olivine limits the size of the largest earthquakes and the heights of the tallest mountains on Earth. By comparing the results of our simulations with data from olivine deformation experiments we are able to better interpret the experimental data.

Hipsec X-Ray Diffraction And Infrared Spectroscopy Studies On Energetic Materials Under Extreme Conditions, Mai Huong Bausch, Yu Liu

Festival of Communities: UG Symposium (Posters)

We conducted a series of experiments on the decompositions of the energetic materials NaBH4, NH3BH3, HMX, and RDX under different pressures using the x-ray diffraction (XRD) technique; we also studied the lesser known but high-performance explosive FOX-7’s behaviors under high pressures using the infrared spectroscopy (IR) technique. For the chemical decomposition of NaBH4 and NH3BH3 we discovered possible x-ray induced hydrogen gas generation; for the decomposition of HMX and RDX, we discovered that the decay rates of these two materials vary with pressure respectively; for the study of FOX-7’s high pressure behaviors we discovered potential phase changes and pressure induced …

High Pressure – Variable Temperature Studies On Pressure Transmitting Media, Vahe Mkrtchyan, Jason Baker, Matthew K. Jacobsen, Ravhi S. Kumar, Andrew Cornelius

Festival of Communities: UG Symposium (Posters)

The pressure transmitting medium is an important element in high pressure physics. A variety of pressure transmitting media exist including Silicone fluid, Daphne Oil, 4:1 Methanol:Ethanol mixture, etc. In this experiment, the hydrostatic limits of pressure transmitting media have been observed at low temperatures and high pressures. In this case, 4:1 Methanol: Ethanol has been used. The hydrostaticity of 4:1 Methanol:Ethanol has been well studied at room temperatures using the fluorescence of ruby by fitting the R1 and R2 lines to Pseudo-Voigt functions. The hydrostacity of the pressure medium was determined by analyzing the full width at half max (FWHM) …

“Magic” Trapping Of Rydberg States For Quantum Information, Muir Morrison, Andrei Derevianko

Festival of Communities: UG Symposium (Posters)

Recent experiments using neutral atoms to manipulate quantum information show promise for constructing a large-scale, practical quantum computer. Achieving such a quantum computer will require less destructive optical traps for the atoms. Using theoretical and computational tools, we consider the feasibility of one possible “magic” trap for rubidium. Preliminary results suggest such trapping may be possible, but more accurate calculations are necessary to reach definitive conclusion.

X-Ray Diffraction On The Thermoelectric Silicides At High Pressure, Deep Patel, Ravhi S. Kumar, Andrew Cornelius

Festival of Communities: UG Symposium (Posters)

Cobalt Silicide (CoSi2) is a transition metal disilicide that has gathered scientific interest due to its interesting thermoelectric properties and applications in silicon-based devices because of their high temperature stability. It has been reported that CoSi2 undergoes a phase transition at around 0.4 GPa and again at 13 GPa. Furthermore, at 13 GPa the material changes from a cubic cell to an orthorhombic cell, but details of the phase transition at 0.4 GPa could not be determined. To further study the properties of CoSi2 and understand its pressure induced phase changes, we recorded the structural behavior of CoSi2 under pressure.

Computational Study Of Carbon Nanotubes Under Strain, Jeremy Feliciano, William Wolfs

Festival of Communities: UG Symposium (Posters)

We perform computational studies of carbon nanotubes (CNTs) using molecular dynamics simulations to examine the behavior of single-walled (SW) and multiwalled (MW) CNTs under large compressive and bending strains. We study the effects of defects, heating and chirality on their properties. Research on CNTs holds great promise for developing new advanced materials in applications ranging from high-strength composites to next-generation electronics.

Graphene: Material That Will Change The Future, Jigar Desai, Darryl Reese

Festival of Communities: UG Symposium (Posters)

Graphene is the most recent material discovered by scientists and is a star on the horizon of materials science and condensed matter physics. The one atom thick, two dimensional materials is an amazing conductor of electricity. Although graphene was not discovered completely until 2004, it has already revealed potential applications and scientists have begun researching ways of developing graphene products for the market. Only two products have been successfully produced so far, but scientists have encountered amazing results. This material has many potential applications in the real world and is about to change the future in a positive way.

Investigation Of Structural And Magnetic Properties Of Iron Clusters Encapsulated In Carbon, Andrew Mohrland, Eunja Kim, Phillipe Weck, Pang Tao, Kenneth Czerwinski

Festival of Communities: UG Symposium (Posters)

Our goal is to investigate and predict the properties of iron-carbon nanostructures by performing numerical calculations using the density-functional theory. We are interested in which nanostructures are most stable, and in how they are likely to form. We have a particular interest in the magnetic properties of carbon "buckyballs" containing iron particles. These structures have potential for biomedical application, including use in anti-cancer treatment. Lone iron clusters have potential for use as a catalyst designed to reduce vehicle emissions.

Structural And Magnetic Properties Of Iron Clusters, Andrew Mohrland, Eunja Kim

Undergraduate Research Opportunities Program (UROP)

Electronic, magnetic, and chemical properties of Fe nanoparticles are of particular interest for materials science, engineering, and metallurgical applications, including biomedical applications (e.g., medical imaging, cancer treatment, etc.). In this study, we search for the most stable geometries of the Fe clusters, Fen, up to n=8. Binding energies, magnetic moments, bond lengths, bond angles, and charge densities of clusters are computed and compared to the available experimental data. The various cluster isomers were examined energetically. We found that, in general, higher dimensional geometries are more stable than lower dimensions (i.e., 1-dimension or 2-dimension). Calculations for the Fe dimer yield a …

Hydrostaticity Of Pressure Transmitting Medium Of 4:1 Methanol: Ethanol At High Pressure And Low Temperature, Christopher Salvo, Andrew Cornelius

Undergraduate Research Opportunities Program (UROP)

In high pressure physics a key element is the pressure transmitting medium. The purpose of this research is to study the hydrostatic limits of pressure transmitting media such as 4:1 Methanol: Ethanol and Silicone Fluid at low temperatures and high pressures.This will be done using a Merrill-Bassett diamond anvil cell (DAC) placed inside of a cryostat capable of reaching temperatures as low as 30 Kelvin for a range to 300 Kelvin. The hydrostaticity of 4:1 Methanol:Ethanol has been heavily studied at room temperature using the fluorescence of ruby by fitting the R1 and R2 lines to pseudo-Voigt functions. The full …

Laser Microraman Study Of Reduced Synthesized Spinel Powders, Alexandra J. Leandre, Michael M. Rodriguez, Joseph Lussier, Brittany Morgan, Brian Hosterman, John W. Farley

Undergraduate Research Opportunities Program (UROP)

The Raman effect is the excitation or de-excitation of vibrational modes resulting from the inelastic scattering of light from a gas, liquid, or solid with a shift in energy from that of the usually incident radiation. Raman microscopy was performed on synthesized spinel powders of solid solution FexCr3-xO4 to determine the dependence of the vibrational modes upon the metal cations. The powders were synthesized in a combustion reaction using metal nitrates and urea. The oxide powders were reduced in a hydrogen/argon gas flow at high temperature.