Physical Sciences and Mathematics Commons^™

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 …

Geochemistry Of Pyrite And Whole Rock Samples From The Getchell Carlin–Type Gold Deposit, Humboldt County, Nevada, Tim A. Howell, Jean S. Cline

Undergraduate Research Opportunities Program (UROP)

Carlin-type gold deposits were not recognized as a new major type of gold deposit until the 1960’s. The Getchell deposit, which is now known to be a Carlin-type gold deposit, was discovered in 1934 (Joralemon, 1951). This deposit is located in north central Nevada (Fig. 1). Much is known about the physical characteristics of Carlin-type gold deposits (Cline et al., 2005). An unusual characteristic of these deposits is that free gold is generally not present. Instead, gold occurs as sub-micrometer particles in the mineral pyrite or marcasite. The marcasite and pyrite that are gold bearing commonly occur as rims on …

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.

Potassium Chlorate Decomposition Under High Pressure, Harrison Ruiz, Michael G. Pravica, Martin Galley

Undergraduate Research Opportunities Program (UROP)

High pressure physics involves placing various substances under high pressure and observing changes in that substance. In this experiment this high amount of pressure is induced using a diamond anvil cell. A diamond anvil cell uses a metal gasket to hold the sample between two diamonds, which will press on the sample to reach high pressures. High pressures are reached with a moderate amount of force by exerting that force over a small area. Diamonds are used for the compression because of their hardness and ability to resist compression. The pressure being exerted on the sample using a diamond anvil …

Determination Of Olivine Orientation Dependence Through Raman Spectroscopy, Alexandra J. Leandre, Joseph Lussier, Brittany Morgan, Michael Rodriguez

Undergraduate Research Opportunities Program (UROP)

Raman spectra were taken of olivine for analysis of vibrational energy intensity ratios. This allowed for determination of its crystal orientation. Garnet inclusions in peridotite were mapped and Raman spectra were taken for these as well. The inclusions could not identified, and data from the Raman spectra proved inconclusive due to difficulty in removing background signal.

Biogeochemical Investigation Of Soda Lake, Kathryn Bywaters, Shaneen Braswell, David Crowther, Bernadette Leonis, Jeremy Memmott, Farrah Moazeni, Christian H. Fritsen

Undergraduate Research Opportunities Program (UROP)

Big Soda Lake, Nevada, is a terminal, volcanic crater lake whose water level is maintained exclusively by groundwater. The crater is composed of volcanic, basaltic sand and the lake is ~60 m deep (Rush, 1972). The lake is meromictic with a distinct chemocline (Kimmel et al. 1978). The chemocline currently rests at ~40 m and is reflected in both specific conductivity and salinity measurements. Below the chemocline a redox gradient develops with highly reducing conditions. The pH is consistent throughout the depth of the lake at ~9.5, proving that it is alkaline in nature. It is further stratified by both …

Synthesis Of Bis-Styrylbenzene Derivatives Via Wittig-Horner Reaction, Joseph K. Wray, Tae Soo Jo, Pradip K. Browmik

Undergraduate Research Opportunities Program (UROP)

Alzheimer’s Disease is now one of the most common diseases affecting the elderly population. Recently, bis-styrylbenzene derivatives have been shown to reduce the formation of Beta-amyloid plaques in the brain which are profoundly correlated with this disease. Finding new biologically active compounds which can reduce or prevent Alzheimer’s Disease has drawn much attention over the past few decades. Georg Wittig, Nobel Prize Winner in Chemistry, 1979.

Thin Film Optical Filter Fabrication And Characterization, Adam G. Hammouda, David P. Shelton

Undergraduate Research Opportunities Program (UROP)

Thin film coatings have a large number of applications. For example, one can eliminate unwanted reflection on a photographic lens or unwanted wavelengths of light in optics experimentation. The fabrication and characterization of films whose refractive indices can be arbitrarily modulated (‘Rugate Filters’) is an ongoing exploration in materials science1,2. Therefore, calibrating a process which can manufacture such films is a relevant pursuit in forwarding such explorations. Reactive magnetron sputter deposition is a commonly used technique for the productions of thin films3,4. This technique steadily flows reactive gas (RG) into a vacuum chamber in which an electric field has been …

High Pressure X-Ray Diffraction Studies On Zrfe2: A Potential Hydrogen Absorption Medium, Dylan D. Wood, Ravhi S. Kumar

Undergraduate Research Opportunities Program (UROP)

The potential application of intermetallic compounds (IMC) under high hydrogen pressure in studies of hydrogen sorption properties is defined by two important properties. Intermetallics of Laves phases have a suitable binding energy for hydrogen which allows its absorption or desorption near room temperature and atmospheric pressure. High pressures allow to efficiently interact hydrogen with intermetallics, which were considered nonhydride forming [1,2]. For example, ZrFe2, ZrCo2, and ZrFe2 possess fairly high hydrogen absorption capacity at high pressures [3]. A nonactivated ZrFe2 sample starts to interact with hydrogen only at 80 MPa, while equilibrium absorption and desorption pressures of the activated alloy …

Properties Of Z≥6 Galaxies In Cosmological Sph Simulations, Jason Jaacks

Undergraduate Research Opportunities Program (UROP)

Recent upgrades to the Hubble Space Telescope have given observers their deepest look into our Universe yet, seeing nearly 13 billion years into the past. This new observational data has presented those of us that use simulations to study the early Universe a benchmark opportunity to evaluate the ability of these codes to reproduce the photometric properties being observed. Establishing this agreement allows us to probe deeper into the physical properties such as mass, star formation histories and star formation rates of these early galaxies. This research lays the ground work for examining the contribution of primordial galaxies to the …

Similarity Of Climate Change Data For Antarctica And Nevada, Corbin Benally, Shahram Latifi, Karletta Chief

Undergraduate Research Opportunities Program (UROP)

The correlation between temperature and carbon dioxide concentration in the past one hundred years is studied. Separate graphs containing data from Vostok, Antarctica and the Mojave desert/mountain west (Nevada region) are presented. Using data obtained from these graphs, an attempt is made to explain the results and investigate the similarity of these results for Antarctica and Nevada. The importance of this study lies in the fact that if data show the same trend in the two regions, many findings for climate change in Antarctica may readily be validated and employed for Nevada.

Chemical Weathering Of Serpentinite Rocks And Implications For Atmospheric Co2 Carbonation, Valerie Tu, Julie Baumeister, Elisabeth Hausrath

Undergraduate Research Opportunities Program (UROP)

No abstract provided.

High Pressure Structural Studies On Eus Nano Particles Up To 52 Gpa, Kristie Canaday, Ravhi S. Kumar

Undergraduate Research Opportunities Program (UROP)

Crystal size reduction in bulk materials changes the structural and magnetic properties considerably [1]. More importantly the transition pressure is strongly influenced by temperature, pressure, and the crystallite size effect. Rare earth europium chalcogenides crystallize in the NaCl (rock salt) type structure. The interest in Eu nanomaterials is motivated by the possibility of their use in magnetic devices [2,3]. Recent studies suggest that europium chalcogenide nanocrystals exhibit significant changes in their structural and magnetic properties, compared to bulk chalcogenides, when the nanocrystal diameter decreases. The crystal structure and phase transition behavior of EuS nanoparticles have been investigated and compared as …

High Pressure Studies Of Titanium Hydride Up To 50 Gpa With Synchrotron X-Ray Diffraction, Greg Harding, Patricia Kalita, Stanislav Sinogeikin, Andrew Cornelius

Undergraduate Research Opportunities Program (UROP)

Titanium dihydride has the potential to play an important role in the efficiency of high density hydrogen storage. The structural instability of TiH2 at high pressures makes an accurate characterization of its structure a vital part of understanding its behavior. A sample of TiH2 was placed in a diamond anvil cell and studied from ambient pressure up to 53 GPa using in situ synchrotron x-ray diffraction at the Advanced Photon Source (APS) of Argonne National Laboratory (Sector 16, HPCAT). From data of the evolution of the structure with pressure, an equation of state was obtained to model the behavior of …

High Pressure Infrared Studies Of Hmx, Jennifer Wojno, Michael G. Pravica, Martin Galley

Undergraduate Research Opportunities Program (UROP)

We are studying the effects of pressure on HMX (Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) using infrared spectroscopy. The sample is put under pressure using a diamond anvil cell at ambient temperature, data is collected at the National Synchrotron Light Source in Brookhaven National Laboratory. In analyzing this data, we hope to learn more about the molecular vibrations as the molecule bends and deforms under pressure. Such understanding could aid in determining new safety standards or more efficient ways of using HMX. In future studies, we intend to include the aspect of temperature variation in addition to pressure, with the goal of describing the molecule …

Y-Aminobutyric Acid Inhibits Synergistic Interleukin-6 Release And Increases Intracellular Cytokine Content In C6 Astrocytoma Cells In Vitro, Daniella Sandoval, Becky M. Hess, Bryan L. Spangelo

Undergraduate Research Opportunities Program (UROP)

Alzheimer’s disease (AD) is a neurodegenerative disorder that is characterized by memory loss and is the most common cause of dementia. It is has been hypothesized that pro-inflammatory cytokines induce the inflammation that is believed to be the cause of the neuronal death that is associated with AD. γ-aminobutyric acid (GABA) is a major inhibitory neurotransmitter in the Central Nervous System possessing membrane hyperpolarization or depolarization activities. A decline in GABA may enhance cytokine release in Alzheimer’s disease resulting in neuroinflammation. Therefore, we investigated the GABA-mediated suppression of the synergistic release of interleukin-6 (IL-6) induced by interleukin 1- (IL-1) and …

Synthesis Of Novel Aromatic Quinols For Colon And Renal Cancers, Bradley J. Davey, Tae Soo Jo, Pradip K. Bhowmik

Undergraduate Research Opportunities Program (UROP)

Colon Cancer: The third most common cancer in USA. More than 1 million Americans currently living with colon cancer. 148,810 new cases expected in 2010. 50,000 deaths annually.

Renal Cancer: Approximately 58,000 people diagnosed in USA annually. Seventh most common cancer and tenth most common cause of cancer related death in men.

Aromatic quinols have demonstrated in vitro antitumor activity. Three heteroaromatic quinols show antitumor activity.

Undergraduate Research Opportunities Program 2010, University Of Nevada, Las Vegas

Undergraduate Research Opportunities Program (UROP)

The Undergraduate Research Opportunities Program (UROP) cultivates and supports research partnerships and invites undergraduates to work as the junior colleagues of faculty. The program offers the opportunity to work on cutting edge research—whether you join established research projects or pursue your own ideas. As participants, undergraduates engage in each phase of standard research activity: developing research plans, writing proposals, conducting research, analyzing data. and presenting research results in oral and written form. The projects take place over the summer, and research can be done in any academic department or interdisciplinary laboratory. Projects can last for an entire semester, and many …