Resource Type

Residual stress measurement in YBCO thin films. (open access)

Residual stress measurement in YBCO thin films.

Residual stress in YBCO films on Ag and Hastelloy C substrates was determined by using 3-D optical interferometry and laser scanning to measure the change in curvature radius before and after film deposition. The residual stress was obtained by appropriate analysis of curvature measurements. Consistent with residual thermal stress calculations based on the thermal expansion coefficient mismatch between the substrates and YBCO film, the measured residual stress in the YBCO film on Hastelloy C substrate was tensile, while it was compressive on the Ag substrate. The stress values measured by the two techniques were generally in good agreement, suggesting that optical interferometry and laser scanning have promise for measuring residual stresses in thin films.
Date: May 13, 2002
Creator: Cheon, J. H. & Singh, J. P.
System: The UNT Digital Library
A GIS/Simulation Framework for Assessing Change in Water Yield over Large Spatial Scales (open access)

A GIS/Simulation Framework for Assessing Change in Water Yield over Large Spatial Scales

Recent legislation to,initiate vegetation management in the Central Sierra hydrologic region of California includes a focus on corresponding changes in water yield. This served as the impetus for developing a combined geographic information system (GIS) and simulation assessment framework. Using the existing vegetation density condition, together with proposed rules for thinning to reduce fire risk, a set of simulation model inputs were generated for examining the impact of the thinning scenario on water yield. The approach allows results to be expressed as the mean and standard deviation of change in water yield for each 1 km2 map cell that is treated. Values for groups of cells are aggregated for typical watershed units using area-weighted averaging. Wet, dry and average precipitation years were simulated over a large region. Where snow plays an important role in hydrologic processes, the simulated change in water yield was less than 0.5% of expected annual runoff for a typical water shed. Such small changes would be undetectable in the field using conventional stream flow analysis. These results suggest that use of water yield increases to help justify forest-thinning activities or offset their cost will be difficult.
Date: November 13, 1999
Creator: Graham, R.; Hargrove, W.W.; Huff, D.D.; Nikolov, N. & Tharp, M.L.
System: The UNT Digital Library
Three-dimensional lithographically-defined organotypic tissue arrays for quantitative analysis of morphogenesis and neoplastic progression (open access)

Three-dimensional lithographically-defined organotypic tissue arrays for quantitative analysis of morphogenesis and neoplastic progression

Here we describe a simple micromolding method to construct three-dimensional arrays of organotypic epithelial tissue structures that approximate in vivo histology. An elastomeric stamp containing an array of posts of defined geometry and spacing is used to mold microscale cavities into the surface of type I collagen gels. Epithelial cells are seeded into the cavities and covered with a second layer of collagen. The cells reorganize into hollow tissues corresponding to the geometry of the cavities. Patterned tissue arrays can be produced in 3-4 h and will undergo morphogenesis over the following one to three days. The protocol can easily be adapted to study a variety of tissues and aspects of normal and neoplastic development.
Date: February 13, 2008
Creator: Nelson, Celeste M.; Inman, Jamie L. & Bissell, Mina J.
System: The UNT Digital Library
The Microbial Detection Array Combined with Random Phi29-Amplification used as a Diagnostic Tool for Unbiased Virus Detection in Clinical Samples (open access)

The Microbial Detection Array Combined with Random Phi29-Amplification used as a Diagnostic Tool for Unbiased Virus Detection in Clinical Samples

None
Date: April 13, 2011
Creator: Erlandsson, L.; Rosenstierne, M. W.; McLoughlin, K.; Jaing, C. & Fomsgaard, A.
System: The UNT Digital Library
Hadron Spectroscopy and Wavefunctions in QCD and the AdS/CFT Correspondence (open access)

Hadron Spectroscopy and Wavefunctions in QCD and the AdS/CFT Correspondence

The AdS/CFT correspondence has led to important insights into the properties of quantum chromodynamics even though QCD is a broken conformal theory. We have recently shown how a holographic model based on a truncated AdS space can be used to obtain the hadronic spectrum of light q{bar q}, qqq and gg bound states. Specific hadrons are identified by the correspondence of string modes with the dimension of the interpolating operator of the hadron's valence Fock state, including orbital angular momentum excitations. The predicted mass spectrum is linear M {proportional_to} L at high orbital angular momentum, in contrast to the quadratic dependence M{sup 2} {proportional_to} L found in the description of spinning strings. Since only one parameter, the QCD scale LQCD, is introduced, the agreement with the pattern of physical states is remarkable. In particular, the ratio of D to nucleon trajectories is determined by the ratio of zeros of Bessel functions. The light-front quantization of gauge theories in light-cone gauge provides a frame-independent wavefunction representation of relativistic bound states, simple forms for current matrix elements, explicit unitarity, and a trivial vacuum. The light-front Fock-state wavefunctions encode the bound state properties of hadrons in terms of their quark and gluon degrees …
Date: October 13, 2005
Creator: Brodsky, Stanley J.; de Teramond, Guy F. & U., /SLAC /Costa Rica
System: The UNT Digital Library
Fluorescence Detection of Nitrogen Dioxide with Perylene/PMMA Thin Films (open access)

Fluorescence Detection of Nitrogen Dioxide with Perylene/PMMA Thin Films

None
Date: July 13, 2000
Creator: Saski, Darryl Y.; Singh, Seema; Cox, Jimmy D. & Pohl, Phillip I.
System: The UNT Digital Library
Evidence for Nodal Superconductivity in LaFePO from Scanning SQUID Susceptometry (open access)

Evidence for Nodal Superconductivity in LaFePO from Scanning SQUID Susceptometry

We measure changes in the penetration depth {lambda} of the T{sub c} {approx} 6 K superconductor LaFePO. In the process scanning SQUID susceptometry is demonstrated as a technique for accurately measuring local temperature-dependent changes in {lambda}, making it ideal for studying early or difficult-to-grow materials. {lambda} of LaFePO is found to vary linearly with temperature from 0.36 to {approx} 2 K, with a slope of 143 {+-} 15 {angstrom}/K, suggesting line nodes in the superconducting order parameter. The linear dependence up to {approx} T{sub c}/3 is similar to the cuprate superconductors, indicating well-developed nodes.
Date: April 13, 2009
Creator: Hicks, Clifford W.; Lippman, Thomas M.; /Stanford U., Geballe Lab. /SLAC; Huber, Martin E.; /Colorado U., Denver; Analytis, James G. et al.
System: The UNT Digital Library
Gemini Near Infrared Spectrograph–Distant Quasar Survey: Augmented Spectroscopic Catalog and a Prescription for Correcting UV-based Quasar Redshifts (open access)

Gemini Near Infrared Spectrograph–Distant Quasar Survey: Augmented Spectroscopic Catalog and a Prescription for Correcting UV-based Quasar Redshifts

Article describes how quasars at z ≳ 1 most often have redshifts measured from rest-frame ultraviolet emission lines. One of the most common such lines, C ivλ1549, shows blueshifts up to ≈5000 km s−1 and in rare cases even higher. The authors present spectroscopic measurements for 260 sources at 1.55 ≲ z ≲ 3.50 having −28.0 ≲ Mi ≲ − 30.0 mag from the Gemini Near Infrared Spectrograph–Distant Quasar Survey (GNIRS-DQS) catalog, augmenting the previous iteration, which contained 226 of the 260 sources whose measurements are improved upon in this work.
Date: June 13, 2023
Creator: Matthews, Brandon M.; Dix, Cooper; Shemmer, Ohad; Brotherton, Michael S.; Myers, Adam D.; Andruchow, I. et al.
System: The UNT Digital Library
A time-frequency smoothing algorithm for cyclic spectral analysis (open access)

A time-frequency smoothing algorithm for cyclic spectral analysis

A hybrid smoothing algorithm is described that smooths first in time and then in frequency. The time-frequency smoothing algorithm is designed to compute estimates of the cyclic (cross) spectrum along lines of constant cycle frequency. A variation on the algorithm, one that incorporates the One Bit Spectral Correlation Algorithm (OBSCA), is also described. A simulation study is presented that evaluates the algorithms.
Date: August 13, 1992
Creator: Roberts, R. S.
System: The UNT Digital Library
Fashion consumption during COVID-19: Comparative analysis of changing acquisition practices across nine countries and implications for sustainability (open access)

Fashion consumption during COVID-19: Comparative analysis of changing acquisition practices across nine countries and implications for sustainability

Article explores and compares changes in clothing acquisition practices during COVID-19 across nine countries: the USA, the UK, Finland, Germany, Switzerland, Iran, Czech Republic, India, and Hong Kong SAR.
Date: April 13, 2022
Creator: Vladimirova, Katia; Henninger, Claudia E.; Joyner-Martinez, Cosette; Iran, Samira; Diddi, Sonali; Durrani, Marium et al.
System: The UNT Digital Library
The Injection Laser System on the National Ignition Facility (open access)

The Injection Laser System on the National Ignition Facility

The National Ignition Facility (NIF) is currently the largest and most energetic laser system in the world. The main amplifiers are driven by the Injection Laser System comprised of the master oscillators, optical preamplifiers, temporal pulse shaping and spatial beam formatting elements and injection diagnostics. Starting with two fiber oscillators separated by up to a few angstroms, the pulse is phase modulated to suppress SBS and enhance spatial smoothing, amplified, split into 48 individual fibers, and then temporally shaped by an arbitrary waveform generator. Residual amplitude modulation induced in the preamplifiers from the phase modulation is also precompensated in the fiber portion of the system before it is injected into the 48 pre-amplifier modules (PAMs). Each of the PAMs amplifies the light from the 1 nJ fiber injection up to the multi-joule level in two stages. Between the two stages the pre-pulse is suppressed by 60 dB and the beam is spatially formatted to a square aperture with precompensation for the nonuniform gain profile of the main laser. The input sensor package is used to align the output of each PAM to the main laser and acquire energy, power, and spatial profiles for all shots. The beam transport sections split …
Date: December 13, 2006
Creator: Bowers, Mark; Burkhart, Scott; Cohen, Simon; Erbert, Gaylen; Heebner, John; Hermann, Mark et al.
System: The UNT Digital Library
Monitoring Annual Urban Changes in a Rapidly Growing Portion of Northwest Arkansas with a 20-Year Landsat Record (open access)

Monitoring Annual Urban Changes in a Rapidly Growing Portion of Northwest Arkansas with a 20-Year Landsat Record

This article employs a time series Landsat stack covering the period from 1995 to 2015 to detect the urban dynamics in Northwest Arkansas via a two-stage classification approach.
Date: January 13, 2017
Creator: Reynolds, Ryan; Liang, Lu; Li, XueCao & Dennis, John
System: The UNT Digital Library
16th National Conference of Black Physics Students - Physics: Science That Unlocks the Secrets of Nature (open access)

16th National Conference of Black Physics Students - Physics: Science That Unlocks the Secrets of Nature

16th National Conference of Black Physics Students - The agenda and its report.
Date: March 13, 2002
Creator: unknown
System: The UNT Digital Library
Correlations between D and Dbar mesons in high energy photoproduction (open access)

Correlations between D and Dbar mesons in high energy photoproduction

Over 7000 events containing a fully reconstructed D{bar D} pair have been extracted from data recorded by the FOCUS photoproduction experiment at Fermilab. Preliminary results from a study of correlations between D and {bar D} mesons are presented. Correlations are used to study perturbative QCD predictions and investigate non-perturbative effects. We also present a preliminary result on the production of {psi}(3770).
Date: November 13, 2002
Creator: Gottschalk, Erik E
System: The UNT Digital Library
Locally Enhanced Conductivity due to the Tetragonal Domain Structure in LaAlO3/SrTiO3 Heterointerfaces (open access)

Locally Enhanced Conductivity due to the Tetragonal Domain Structure in LaAlO3/SrTiO3 Heterointerfaces

None
Date: March 13, 2014
Creator: Kalisky, Beena; Spanton, Eric M.; Noad, Hilary; Kirtley, John R.; Nowack, Katja C.; Bell, Christopher et al.
System: The UNT Digital Library
Cardiovascular function, compliance, and connective tissue remodeling in the turtle, Trachemys scripta, following thermal acclimation (open access)

Cardiovascular function, compliance, and connective tissue remodeling in the turtle, Trachemys scripta, following thermal acclimation

This article suggests that cold acclimation alters cardiac shunting patterns with an increased R-L shunt flow, achieved through reducing systemic resistance and increasing systemic blood flow.
Date: April 13, 2016
Creator: Keen, Adam N.; Shiels, Holly A. & Crossley, Dane A., II
System: The UNT Digital Library
Proceedings AESOP Conference Volume 17 (open access)

Proceedings AESOP Conference Volume 17

None
Date: September 13, 1977
Creator: unknown
System: The UNT Digital Library
Proceedings of the 2011 Monitoring Research Review: Ground-Based Nuclear Explosion Monitoring Technologies (open access)

Proceedings of the 2011 Monitoring Research Review: Ground-Based Nuclear Explosion Monitoring Technologies

These proceedings contain papers prepared for the Monitoring Research Review 2011: Ground-Based Nuclear Explosion Monitoring Technologies, held 13-15 September, 2011 in Tucson, Arizona. These papers represent the combined research related to ground-based nuclear explosion monitoring funded by the National Nuclear Security Administration (NNSA), Defense Threat Reduction Agency (DTRA), Air Force Research Laboratory (AFRL), US Army Space and Missile Defense Command, Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO), National Science Foundation (NSF), and other invited sponsors. The scientific objectives of the research are to improve the United States' capability to detect, locate, and identify nuclear explosions. The purpose of the meeting is to provide the sponsoring agencies, as well as potential users, an opportunity to review research accomplished during the preceding year and to discuss areas of investigation for the coming year. For the researchers, it provides a forum for the exchange of scientific information toward achieving program goals, and an opportunity to discuss results and future plans. Paper topics include: seismic regionalization and calibration; detection and location of sources; wave propagation from source to receiver; the nature of seismic sources, including mining practices; hydroacoustic, infrasound, and radionuclide methods; on-site inspection; and data processing.
Date: September 13, 2011
Creator: Wetovsky, Marvin A.; Patterson, Eileen F. & Sandoval, Marisa N.
System: The UNT Digital Library