Physics Commons^™

Electrochemical Etching Technique For Fabricating Tungsten Nanotips, Thomas Bersano, Bruno Deharak, Faculty Advisor

John Wesley Powell Student Research Conference

No abstract provided.

An Analytical And Numerical Treatment Of The Carter Constant For Inclined Elliptical Orbits About A Massive Kerr Black Hole, Peter Komorowski, Sree Ram Valluri, Martin Houde

WORLDiscoveries Research Showcase

In an extreme binary black hole system, an orbit will increase its angle of inclination (i) as it evolves in Kerr spacetime. We focus our attention on the behaviour of the Carter constant (Q) for near-polar orbits. The value of Q for bound orbits is non-negative; and an increase in Q corresponds to an increase in i. For a Schwarzschild black hole, the polar orbit represents the boundary between the prograde and retrograde orbits at which Q is at its maximum value. The introduction of spin (S = |J|/M2) to the massive black hole causes this boundary, or Abutment, to …

The Effects Of Pressure On Wide Bandgap Gan Semiconductors, William Kang, Linda Tran, Eunja Kim

Undergraduate Research Opportunities Program (UROP)

Gallium nitride (GaN) is a group-III nitride semiconductor; which may prove useful in developing optical instruments that operate under high ambient pressures. The purpose of this project is to examine the properties of GaN under varying conditions. The methods used in this experiment consist of modeling free energy as a function of lattice constants; calculating bond lengths, bond strengths, and bulk moduli; and comparing the resultant data with values in published literature. We will also compare these results with experimental data drawn from x-ray diffraction scans. By doing so, we hope to determine whether gallium nitride is suitable for use …

Phonon Density Of States Of Iron Solid Solutions At Ambient And High Pressures Using Nuclear Inelastic X-Ray Scattering (Nrixs), Samantha L. Combs, Elizabeth A. Tanis, Malcolm Nicol

Undergraduate Research Opportunities Program (UROP)

Nuclear resonant inelastic x-ray scattering (NRIXS) of synchrotron radiation uses the energy transferred during the inelastic nuclear absorption of photons to determine phonon density of states for solid Mössbauer isotopes. This type of experiment can be conducted at ambient and high pressures with the use of a diamond anvil cell (DAC) and a rhenium gasket. Here, we are concerned with the phonon DOS of α-FePt 10% at pressures up to 30 GPa, as well as FeAl 4.3%, 6.4%, and 27.1% at ambient pressures. The iron samples used are doped in order to increase the pressure at which the alpha to …

Structural Studies Of Crsi2 At High Pressures And Temperatures, Weldu Gabrimicael, Ravhi S. Kumar, Andrew Cornelius

Undergraduate Research Opportunities Program (UROP)

It is of extreme importance to develop new potential energy sources to reduce dependence on fossil fuels. As a result of this, the study of thermoelectric materials, capable of changing heat into electrical energy, has become a field of great interest regarding fundamental properties. To help better understand these materials, facilities for the measurement of relevant properties at high pressure have been developed, but lack the ability to characterize the materials at high temperature and pressure. Therefore, this project has the goal of developing a heater arrangement to be used in conjunction with the high pressure capabilities already developed to …

The Search For Ferroelectric Domain Structures In Carbohydrate Glasses Using Atomic Force Microscopy, Louis S. Prahl, David P. Shelton

Undergraduate Research Opportunities Program (UROP)

D-glucose was studied as a possible candidate for ferroelectric domain imaging using an Atomic Force Microscope (AFM). The large dipole moment of carbohydrates is such that they may show localized ferroelectric domain formation in liquid phase. Samples were heated at their melting point on glass slides and then left to cool to room temperature in a desiccator. Differential Thermal Analysis (DTA) was used to test the effectiveness of this method, and it was found that the oven preparation created samples with 41% crystallinity, where both a glass transition and sharp melting peak were observed. DTA was again used to find …

Raman Studies Of 1,3,5,7 Cyclooctatetraene At High Pressure, Martin Galley, Ed Romano, Sergey Tkachev, Michael Pravica

Undergraduate Research Opportunities Program (UROP)

We performed Raman spectroscopic studies of 1,3,5,7-cyclooctatetraene at elevated pressures up to 10 GPa with the aim of examining possible planarization of the molecule and further studying two prior-discovered phases of the solid with pressure. The Raman excitation source was a Krypton-ion laser operating at 674.1 nm (give wavelength).

1,3,5,7 Cyclooctatetraene has an octagonal formation however it is not aromatic or anti-aromatic (not a subject to the 4n+2 Huckel’s rule) [1]. As a result, its adopts a somewhat reactive tub shape. Upon the addition or removal of one to two electrons under ambient conditions, the molecule planarizes and becomes aromatic …

Spatially Resolved Optical Absorption Spectrometry And Single Crystal Diffraction On Metamict Materials, Alison Savage, Oliver Tschauner, Sergey Tkachev

Undergraduate Research Opportunities Program (UROP)

A major goal in developing storage medium for radioactive waste is the identification of chemically suitable and durable material for storage in repositories (Lumpkin 2006). Radiation damage induces enhanced chemical diffusion and structural breakdown of the host materials, which can lead to contamination of the surrounding environment. During this project four different naturally occurring materials which are common carriers of thorium and uranium were examined : gadolinite, perrierite, allanite, and pyrochlore of which the first three are silicates and pyrochlore being an oxide. Their spectra and absorptions bands were examined to identify prominent features due to radiation damage. The goal …

Nuclear Energy, Steve Kraft

Native American Forum on Nuclear Issues

Abstract:

-Why Nuclear Energy?

-The lesson of the last 20 years in U.S. electricity policy:

– Diversified fuel and technology portfolio is essential

– All fuels and technologies (nuclear, coal, natural gas, renewables, efficiency) have a legitimate role

-The challenge for the future:

– Preserving/restoring diversified portfolio

– Ensuring resource adequacy, particularly in competitive markets

-Expanded use of nuclear energy is part of the answer

– Integrated used fuel management supports nuclear competitiveness

Session 11 - Radioactive Dispersion Devices (Rdd): What Are The Odds?, Dennis Bechtel

International Symposium on Technology and Society

Since the tragic events of September 11th, 2001 there has been apprehension that the United States may be ill-prepared to prevent future terrorist events. One source of concern is that a Radioactive Dispersion Device (RDD) could be detonated at a vulnerable target anywhere in the nation. A RDD, also known as a “dirty bomb, is a conventional explosive packed with radioactive material. The explosion could disperse radioactive material over a wide area. The target could be an icon associated with American democracy and government, critical systems and infrastructure, a water supply, a nuclear power plant and others. Such an event …

Session 1 - Cold War Technoscience In Nevada: The Nevada Test Site Oral History Project, Mary Palevsky

International Symposium on Technology and Society

During the Cold War, the United States conducted over 1000 nuclear weapons tests. Of those, 928 took place at the Nevada Test Site (NTS). One hundred tests were in the atmosphere and 921 underground at the 1375 square mile site located 65 north of Las Vegas. Nevada Test Site Oral History Project (NTSOHP) researchers have conducted over 300 hours of interviews with individuals affiliated with and impacted by the NTS, documenting the diversity of experience among many communities of voices including: weapons scientists, test site officials, laborers, contractors and support personnel, the military, American Indians, communities downwind of the NTS, …

Session 1 - Rationalizing The Home Front: The Cold War, The Nevada Test Site, And Radiation Exposure, Leisl A. Carr

International Symposium on Technology and Society

Beginning in 1953, radiation exposure and its effects became a hotly contested issue between the government, members of communities surrounding the Nevada Test Site (NTS), and researchers within the national scientific community. The Atomic Energy Commission (AEC), concerned about maintaining a continental testing facility and aware that atomic testing would impact communities surrounding the NTS, sent representatives to areas potentially affected by fallout to instruct and reassure the affected public. How government officials perceived neighboring communities and how these communities perceived these representatives of the government often determined public responses to the atomic testing program. The story of radiation monitors …