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An Ultra-Precise System for Electrical Resistivity Tomography Measurements

Description: The objective of this research was to determine the feasibility of building and operating an ERT system that will allow measurement precision that is an order of magnitude better than existing systems on the market today and in particular if this can be done without significantly greater manufacturing or operating costs than existing commercial systems. Under this proposal, we performed an estimation of measurement errors in galvanic resistivity data that arise as a consequence of the type of e… more
Date: December 9, 2008
Creator: LaBrecque, Douglas J & Adkins, Paula L
Partner: UNT Libraries Government Documents Department
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Automated Impedance Tomography for Monitoring Permeable Reactive Barrier Health

Description: The objective of this research was the development of an autonomous, automated electrical geophysical monitoring system which allows for near real-time assessment of Permeable Reactive Barrier (PRB) health and aging and which provides this assessment through a web-based interface to site operators, owners and regulatory agencies. Field studies were performed at four existing PRB sites; (1) a uranium tailing site near Monticello, Utah, (2) the DOE complex at Kansas City, Missouri, (3) the Denver… more
Date: July 2, 2009
Creator: LaBrecque, D J & Adkins, P L
Partner: UNT Libraries Government Documents Department
open access

A New Form of Standard Resistance

Description: Report issued by the Bureau of Standards over new developments of electrical resistivity in manganin wire coils. The results of the developments are discussed. This report includes tables, illustrations, and photographs.
Date: October 1, 1908
Creator: Rosa, Edward B.
Partner: UNT Libraries Government Documents Department
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The Influence of Radiation-Produced Defects on the Precipitation of Carbon in Iron

Description: The severe local damage caused by neutron irradiation of an alloy can create extra sites for the nucleation of phase changes. This effect of enhanced nucleation has been studied in the iron--carbon system. Measurements were made by electrical resistivity, internal friction, and electron microscopy. Two effects were found. When the alloy is irradiated at ambient temperature (~60 deg C) the number of precipitation particles formed and, hence, the rate of precipitation of carbon, is ten times the … more
Date: 1962
Creator: Fujite, F. E. & Damask, A. C.
Partner: UNT Libraries Government Documents Department
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Resistivity of Vacancy Impurity Pairs

Description: The contribution to electrical resistivity of impurity atoms adjacent to vacancies in metals is calculated. The calculation is based on the Born approximation, which allows separations of the effects of the individual imperfections from interference effects. Lattice relaxation is neglected. The resistivity due to Ag or Zn impurities adjacent to a vacancy in Au is related to the resistivity of the separate imperfections as ∫Ag + vac = ∫ Ag + ∫ vac - 0.11 (∫Ag * ∫vac)^(1/2) ; ∫Zn + vac = ∫Zn + ∫v… more
Date: 1962
Creator: Keller, Joseph M.
Partner: UNT Libraries Government Documents Department
open access

Electrical Resistivity of Rare-Earth Alloys

Description: From abstract: "Resistivities of solid solution alloys in the systems Gd-Lu, Tb-Lu, Gd-Er, and Y-Lu were measured from 4.2-320°K to determine the behavior of the resistivity in alloy systems with magnetic phenomena arising from localized magnetic moments. A large contribution to the residual resistivity is caused by the random distribution of these localized moments through the lattice. An analysis of the lattice resistivity of the metals shows large variations across the heavy rare-earth serie… more
Date: June 5, 1962
Creator: Smidt, F. A. & Daane, A. H. (Adrian Hill), 1919-
Partner: UNT Libraries Government Documents Department
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Electrical Resistivity and Seismic Surveys at the Nevada Test Site, Nevada, April 2007

Description: In April 2007, the USGS collected direct-current (DC) electrical resistivity data and shear- (S) and compressional- (P) wave seismic data to provide new detail of previously mapped, overlapping fault splays at two administrative areas in the Nevada Test Site (NTS). In NTS Area 7, we collected two-dimensional DC resistivity data along a transect crossing the Yucca Fault parallel to, and between, two transects along which resistivity data were collected in a previous study in 2006. In addition, w… more
Date: March 30, 2009
Creator: Haines, Seth S.; Burton, Bethany L.; Sweetkind, Donald S. & Asch, Theodore H.
Partner: UNT Libraries Government Documents Department
open access

The Resistivity of Cu₃Au During Neutron Irradiation

Description: Report discussing an experiment in which samples of initially ordered and disordered copper-gold alloy were exposed to the neutron flux of a graphite moderated nuclear reactor. "Two specimens were irradiated at the same time and at the same position in the reactor. Their temperature was controlled at 80°C. Electrical resistivity measurements were made on the specimens during the course of the irradiation."
Date: February 26, 1952
Creator: Glick, H. L.; Brooks, F. C.; Witzig, W. F. & Johnson, W. E.
Partner: UNT Libraries Government Documents Department
open access

Electrical Properties of the Tungsten Bronzes

Description: From abstract: "The electrical resistivity of NaxWO3, LixWO3, and KxWO3 has been measured at 300°K. The range of x-values was 0.25 < x < 0.9. All resistivities were characteristic of a metal and lie on a single curve. An extrapolation of the conductivity curve to zero conductivity indicated that the tungsten bronzes should be semiconductors for x < 0.25. The resistivities that have been measured for tungsten bronzes with x < 0.25 showed semiconducting behavior. The resistivity of LixWO3 exhibit… more
Date: March 21, 1962
Creator: Shanks, H. R.; Sidles, Paul Howard & Danielson, G. C.
Partner: UNT Libraries Government Documents Department
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The Influence of Particle Morphology and Heat Treatment on the Microstructural Evolution of Silver Inks for Additively Manufactured RF Applications: A Comparison between Nanoflake and Reactive Inks

Description: In recent years, advancements in additive manufacturing (AM) technologies have paved the way for 3D-printed flexible hybrid electronics (FHE) and created opportunities for extending these gains to RF applications. However, printed metal interconnects and devices are typically characterized by high porosity and chemical impurities that significantly limit their electrical conductivity and RF performance compared to bulk equivalents. Using direct ink writing (DIW), two silver inks, a nanoflake su… more
Date: May 2023
Creator: Summers, Jason Masao
Partner: UNT Libraries
open access

Removal of Heavy Metals and Organic Contaminants from Aqueous Streams by Novel Filtration Methods

Description: The removal of hazardous waste, generated by the dismantling of nuclear weapons is a problem that requires urgent attention by the US Department of Energy. Low levels of radioactive contaminants combined with organic solvent residues have leaked from aging containers into the soil and underground water in the surrounding area. Due to the complexity of the problem, it is evident that traditional adsorption methods are ineffective, since the adsorbent tends to saturate with the aqueous component.… more
Date: August 1, 2000
Creator: Rodriguez, N. M.
Partner: UNT Libraries Government Documents Department
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