Physics Commons^™

Charge Transport And Electron Emission Of Disordered Materials: Extensions Of The Walden-Wintle Model For Charge Injection With Electron Beams, Jr Dennison, Alec Sim, Gregory Wilson, Jodie C. Gillespie

Presentations

No abstract provided.

Pre-Breakdown Arcing And Electrostatic Discharge In Dielectrics Under High Dc Electric Field Stress, Allen Andersen, Jr Dennison

Presentations

No abstract provided.

Recentering The Humanities, Mellon Grant For “Through The Looking Glass: The Science Of Art...Or The Art Of Science", Crystal Boyce, Karen Schmidt, Gabe Spalding

Crystal Boyce

This program proposes to bring together the disciplines of art, theatre, physics, and chemistry as represented through the works of Argonne scientists and how their discoveries have advanced the humanities.

Small Satellite Space Environments Effects Test Facility, Jr Dennison, Justin Dekany, Kent Hartley, James S. Dyer, Robert H. Johnson

Presentations

No abstract provided.

One-Dimensional Weakly Nonlinear Model Equations For Rossby Waves, David Henry, Rossen Ivanov

Articles

In this study we explore several possibilities for modelling weakly nonlinear Rossby waves in fluid of constant depth, which propagate predominantly in one direction. The model equations obtained include the BBM equation, as well as the integrable KdV and Degasperis-Procesi equations.

Density Of State Models And Temperature Dependence Of Radiation Induced Conductivity, Jodie C. Gillespie, Jr Dennison, Alec Sim

Presentations

No abstract provided.

Defects Density Of States Model Of Cathodoluminescent Intensity And Spectra Of Disordered Sio2, Amberly Evans Jensen, Jr Dennison

Presentations

No abstract provided.

Electrostatic Discharge And Endurance Time Measurements Of Spacecraft Materials: A Defect-Driven Dynamic Model, Allen Andersen, Jr Dennison, Alec Sim, Charles Sim

Presentations

No abstract provided.

Synergistic Models Of Electron Emission And Transport Measurements Of Disordered Sio2, Jr Dennison, Justin Dekany, Jodie C. Gillespie, Phil Lundgreen, Allen Andersen, Amberly Evans, Greg Wilson, Alec Sim, Ryan Carl Hoffmann

Presentations

No abstract provided.

Variations In Cathodoluminescent Intensity Of Spacecraft Materials Exposed To Energetic Electron Bombardment, Justin Dekany, Justin Christensen, Jr Dennison, Amberly Evans, Greg Wilson, Todd Schneider, Charles W. Bowers, Robert H. Meloy

Presentations

No abstract provided.

Measurements Of Intrinsic Electron Emission Yields Of High Resistivity Ceramic Materials, Justin Dekany, Jr Dennison, Ryan Carl Hoffmann, Clint D. Thomson, Ender Savrun

Presentations

No abstract provided.

Midlatitude Mesospheric Temperature Anomalies During Major Ssw Events As Observed With Rayleigh-Scatter Lidar, Leda Sox, Vincent B. Wickwar, Chad Fish, Josh P. Herron

Leda Sox

While the mesospheric temperature anomalies associated with Sudden Stratospheric Warmings (SSWs) have been observed extensively in the polar regions, observations of these anomalies at midlatitudes are sparse. The original Rayleigh-scatter lidar that operated at the Atmospheric Lidar Observatory (ALO; 41.7°N, 111.8°W) in the Center for Atmospheric and Space Sciences (CASS) on the campus of Utah State University (USU) collected a very dense set of temperature data for 11 years, from 1993 through 2004. The temperatures derived from these data extended over the mesosphere, from 45 to 90 km. This work focuses on the extensive Rayleigh lidar ...

The Bcl-2 Family Protein Bid Is Critical For Pro-Inflammatory Signaling In Astrocytes., Hans-Georg König, Karen S. Coughlan, Sinéad Kinsella, Bridget A. Breen, Jochen Hm Prehn

Physiology and Medical Physics Articles

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by the loss of motoneurons in the spinal cord, brainstem and motor cortex. Mutations in the superoxide dismutase 1 (SOD1) gene represent a frequent genetic determinant and recapitulate a disease phenotype similar to ALS when expressed in mice. Previous studies using SOD1(G93A) transgenic mice have suggested a paracrine mechanism of neuronal loss, in which cytokines and other toxic factors released from astroglia or microglia trigger motoneuron degeneration. Several pro-inflammatory cytokines activate death receptors and may downstream from this activate the Bcl-2 family protein, Bid. We here sought to investigate ...

A Non-Contrast Magnetic Resonance Imaging Technique To Assess Blood-Brain Barrier Permeability, Harini Pandithasekera

University of Western Ontario - Electronic Thesis and Dissertation Repository

The Blood-brain barrier (BBB) regulates the entry of compounds between the blood and the brain, thus plays an important role in brain homeostasis. Studies indicate in disease states such as Alzheimer’s the BBB integrity is compromised. The motive of this project is to investigate the sensitivity of the diffusion-weighted arterial spin labeling (DW-ASL) technique to detect water exchange. Testing the sensitivity requires a reliable method of opening the barrier at specific locations of the brain. Here, a unique technology named focused ultrasound (FUS) has been used to mimic a compromised BBB environment.

A series of experiments were conducted in ...

The Atomic Structure Of Amorphous Oxide Semiconductors, Joe Boesso

DePaul Discoveries

Amorphous oxide semiconductors have important industrial applications in opto-electronic devices due to their transparency and high electrical conductivity. It is important to understand the arrangements of the atoms in these semiconductors since they determine the electrical properties of the materials. To investigate the atomic structure of indium oxide semiconductors, a series of nine thin films were deposited at different temperatures. Wide-angle x-ray scattering data were collected at Argonne National Laboratory. The images for the partially amorphous and fully crystalline films were calibrated, integrated, and analyzed. Structural results include the lattice parameters and positions of the atoms in the bixbyite phase ...

Cosmic Sound In The Lyman Alpha Forest, Spencer Everett, Matt Kwiecien, Cordell Newmiller

DePaul Discoveries

Using the Baryon Oscillation Spectroscopic Survey (BOSS) from the Sloan Digital Sky Survey (SDSS), the authors attempt to detect the baryonic acoustic oscillations (BAOs) using the discrete wavelet transform. The wavelet transform is used to construct the power spectrum of intergalactic clouds of matter at large (Mpc) distance scales. It was found that the wavelet transform used here does not have high enough resolution to detect the BAOs. However, the techniques used in this study allow for future improvements in the transform that could potentially resolve the expected peak in the power spectrum and indicate the existence of BAOs.

Characterization Of Electrical Performance Of Aluminum-Doped Zinc Oxide Pellets, Neel Patel

DePaul Discoveries

Recently, the electronic industry has been shifting towards devices that can be controlled by touching the screen with one or more fingers. This technology is made possible by using transparent conducting oxides (TCOs). Zinc oxide (ZnO) is a potential replacement for the most currently used TCO (indium-tin oxide) due to its comparable optical properties. However, the doping mechanisms of zinc oxide need to be understood and improved. The goal of this research was to prepare n-type, aluminum-doped ZnO. Several dopant percentages were studied to investigate the optimum concentration. The electrical properties for all doping levels improved compared to undoped ZnO.

Viscosity Dependence Of Faraday Wave Formation Thresholds, Lisa M. Slaughter

Symposium

This experiment uses an electromagnetic shaker to produce standing wave patterns on the surface of a vertically oscillating sample of silicon liquid. These surface waves, known as Faraday waves, form shapes such as squares, lines, and hexagons. They are known to be dependent upon the frequency and amplitude of the forcing as well as on the viscosity and depth of the liquid in the dish. At a depth of 4mm and for various silicon liquids having kinematic viscosities of 10, 20, and 38 cSt, we determined the acceleration at which patterns form for frequencies between 10 and 60 Hz. For ...

Exploring The Relationship Between A Fluid Container's Geometry And When It Will Balance On Edge, Ryan J. Moriarty

Physics

At some point while consuming a beverage, many people will idly try to balance its container on edge. The act itself is physically straightforward, merely involving the system's center of mass and achieving a static equilibrium between the opposing torques caused by gravity and the normal force between the container and the surface on which it balances. Further analysis of the act, however, illuminates the richness of the exercise.

These nuances are apparent even in simplified two-dimensional models because of the depth of the relationship between a container's geometry and achieving balance. The purpose of such analysis is ...

Rubidium-Based Atomic Clock, Kate Miles

Physics

In this paper we will explore the process of building an atomic clock from a function generator, go into an in-depth introductory discussion of the Datum LPRO, and examine how rubidium function generators work.