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The Electrochemical Etching Process of a Tungsten Wire

Description: This study produced and analyzed shaped tungsten wire tips formed through electrochemical etching. Specifically, the cone length and the radius of curvature of the tip were analyzed. Having the tips move dynamically through an electrolytic solution, such as potassium hydroxide, and tuning the initial starting depth of the tungsten wire along with the dynamic speed of the tungsten wire as it passed throughout the solution allowed various types of tip profiles to be produced. The tip's radius of … more
Date: August 2021
Creator: Richardson, Aaron Michael
Item Type: Refine your search to only Thesis or Dissertation
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The Electrochemical Properties of the Mercury/lithium Nitrate-potassium Nitrate Eutectic Interface

Description: The original purpose of this investigation was to attempt to apply the coulostatic method directly to a molten salt system. The inability to duplicate the reported capacity data for this system resulted in an investigation of the probable cause of this discrepancy between the data obtained by these different methods (14, 15).
Date: August 1968
Creator: Flinn, David R.
Item Type: Refine your search to only Thesis or Dissertation
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Electrochemical Quartz Crystal Microbalance Study Of Bismuth Underpotential Deposition On Ruthenium And On Electrochemically Formed Ruthenium Oxide

Description: Kinetics and thermodynamics of bismuth (Bi) underpotential deposition (UPD) on ruthenium (Ru) and on electrochemically formed Ru oxide are studied using electrochemical quartz crystal microbalance technique. The Bi UPD and Bi bulk deposition are observed both on Ru and on electrochemically formed Ru oxide electrodes. The anodic peak potential of Bi UPD shifts slightly to positive potential as the scan rate increases. The peak current ratio (IAnode/ICathode) of Bi UPD and Bi bulk increases as th… more
Date: December 2011
Creator: Lin, Po-Fu
Item Type: Refine your search to only Thesis or Dissertation
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Electrochemical Study of Under-Potential Deposition Processes on Transition Metal Surfaces

Description: Copper under-potential deposition (UPD) on iridium was studied due to important implications it presents to the semiconductor industry. Copper UPD allows controlled superfilling on sub-micrometer trenches; iridium has characteristics to prevent copper interconnect penetration into the surrounding dielectric. Copper UPD is not favored on iridium oxides but data shows copper over-potential deposition when lower oxidation state Ir oxide is formed. Effect of anions in solution on silver UPD at plat… more
Date: August 2006
Creator: Flores Araujo, Sarah Cecilia
Item Type: Refine your search to only Thesis or Dissertation
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Electrochemical Synthesis and Applications of Layered Double Hydroxides and Derivatives

Description: Layered double hydroxides (LDH) are a class of anionic clay with alternating layers of positive and negative charge. A metal hydroxide layer with divalent and trivalent metals with a positive charge is complemented by an interlayer region containing anions and water with a negative charge. The anions can be exchanged under favorable conditions. Hydrotalcite (Mg6Al2(OH)16[CO3]·4H2O) and other variations are naturally occurring minerals. Synthetic LDH can be prepared as a powder or film by numero… more
Date: August 2015
Creator: Kahl, Michael S.
Item Type: Refine your search to only Thesis or Dissertation

Electrochemical Synthesis and Characterization of Inorganic Materials from Aqueous Solutions

Description: The dissertation consists of the following three sections: 1. Hydroxyapatite (HA) coatings. In this work, we deposited HA precursor films from weak basic electrolytic solution (pH= 8-9) via an electrochemical approach; the deposits were changed into crystallite coatings of hydroxyapatite by sintering at specific temperatures (600-800 ºC). The formed coatings were mainly characterized by powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microsc… more
Access: Restricted to the UNT Community Members at a UNT Libraries Location.
Date: December 2006
Creator: Yuan, Qiuhua
Item Type: Refine your search to only Thesis or Dissertation
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Electrochemical synthesis of CeO2 and CeO2/montmorillonite nanocomposites.

Description: Nanocrystalline cerium oxide thin films on metal and semiconductor substrates have been fabricated with a novel electrodeposition approach - anodic oxidation. X-ray diffraction analysis indicated that as-produced cerium oxide films are characteristic face-centered cubic fluorite structure with 5 ~ 20 nm crystal sizes. X-ray photoelectron spectroscopy study probes the non-stoichiometry property of as-produced films. Raman spectroscopy and Scanning Electron Microscopy have been applied to analyze… more
Date: December 2003
Creator: Wang, Qi
Item Type: Refine your search to only Thesis or Dissertation
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Electrochemically Deposited Metal Alloy-silicate Nanocomposite Corrosion Resistant Materials

Description: Zinc-nickel ?-phase silicate and copper-nickel silicate corrosion resistant coatings have been prepared via electrochemical methods to improve currently available corrosion resistant materials in the oil and gas industry. A layered silicate, montmorillonite, has been incorporated into the coatings for increased corrosion protection. For the zinc nickel silicate coatings, optimal plating conditions were determined to be a working pH range of 9.3 -9.5 with a borate based electrolyte solution, res… more
Date: May 2013
Creator: Conrad, Heidi Ann
Item Type: Refine your search to only Thesis or Dissertation
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Electrodeless Discharge of Isopropyl Alcohol

Description: Gases at satisfactory pressures fluoresce in the presence of radio frequency radiation (6). Such fluorescent gases have been used to probe fields of radio frequency oscillation and their emission spectra have been recorded and studied. Ions with multiple charges also exist in these gases, (6). In 1941 Oliver (12) observed the fluorescence of an isobutane- isobutene gaseous mix flowing to a pump through a glass tube which was wrapped by a spiral antenna of a sevenmegacycle transmitter. A white d… more
Date: August 1965
Creator: Bryant, Franklin Delano
Item Type: Refine your search to only Thesis or Dissertation
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Electrodeposited Metal Matrix Composites for Enhanced Corrosion Protection and Mechanical Properties

Description: In the oil and gas industry, high corrosion resistance and hardness are needed to extend the lifetime of the coatings due to exposure to high stress and salt environments. Electrodeposition has become a favorable technique in synthesizing coatings because of low cost, convenience, and the ability to work at low temperatures. Electrodeposition of metal matrix composites has become popular for enhanced corrosion resistance and hardness in the oil and gas industry because of the major problems tha… more
Date: May 2016
Creator: Thurber, Casey Ray
Item Type: Refine your search to only Thesis or Dissertation

Electrodeposition of adherent copper film on unmodified tungsten.

Description: Adherent Cu films were electrodeposited onto polycrystalline W foils from purged solutions of 0.05 M CuSO4 in H2SO4 supporting electrolyte and 0.025 M CuCO3∙Cu(OH)2 in 0.32 M H3BO3 and corresponding HBF4 supporting electrolyte, both at pH = 1. Films were deposited under constant potential conditions at voltages between -0.6 V and -0.2 V vs Ag/AgCl. All films produced by pulses of 10 s duration were visible to the eye, copper colored, and survived a crude test called "the Scotch tape test", … more
Access: Restricted to the UNT Community Members at a UNT Libraries Location.
Date: May 2004
Creator: Wang, Chen
Item Type: Refine your search to only Thesis or Dissertation
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Electrodeposition of Copper on Ruthenium Oxides and Bimetallic Corrosion of Copper/Ruthenium in Polyphenolic Antioxidants

Description: Copper (Cu) electrodeposition on ruthenium (Ru) oxides was studied due to important implications in semiconductor industry. Ruthenium, proposed as the copper diffusion barrier/liner material, has higher oxygen affinity to form different oxides. Three different oxides (the native oxide, reversible oxide, and irreversible oxide) were studied. Native oxide can be formed on exposing Ru in atmosphere. The reversible and irreversible oxides can be formed by applying electrochemical potential. Investi… more
Date: August 2007
Creator: Venkataraman, Shyam S.
Item Type: Refine your search to only Thesis or Dissertation
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Electrodeposition of Diamond-like Carbon Films

Description: Electrodeposition of diamond-like carbon (DLC) films was studied on different substrates using two different electrochemical methods. The first electrochemical method using a three-electrode system was studied to successfully deposit hydrogenated DLC films on Nickel, Copper and Brass substrates. The as-deposited films were characterized by scanning electron microscopy (SEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), fourier transform infrared spectroscopy (FTIR) and cyclic vol… more
Date: August 2002
Creator: Chen, Minhua
Item Type: Refine your search to only Thesis or Dissertation
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Electrodeposition of Molybdenum-Based Coatings from Aqueous Alkaline Solutions for Enhanced Corrosion Resistance

Description: Zn-Mo coatings are very promising environment friendly anticorrosive coatings as replacement materials for cadmium and chromium (VI) based conversion layers. Electrodeposition has become a favorable technique in fabricating coatings due to its low cost, ease of use, and overall experimental control of coating quality. Very little research so far has been done for the electrodeposition of Zn-Mo coatings under alkaline conditions. In this work, Zn and Zn-Mo coatings were electrochemically deposit… more
Date: May 2018
Creator: Zhou, Ting
Item Type: Refine your search to only Thesis or Dissertation
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Electrodeposition of Nickel and Nickel Alloy Coatings with Layered Silicates for Enhanced Corrosion Resistance and Mechanical Properties

Description: The new nickel/layered silicate nanocomposites were electrodeposited from different pHs to study the influence on the metal ions/layered silicate plating solution and on the properties of the deposited films. Nickel/layered silicate nanocomposites were fabricated from citrate bath atacidic pHs (1.6−3.0), from Watts’ type solution (pH ~4-5), and from citrate bath at basic pH (~9). Additionally, the new nickel/molybdenum/layered silicate nanocomposites were electrodeposited from citrate bath at p… more
Date: August 2014
Creator: Tientong, Jeerapan
Item Type: Refine your search to only Thesis or Dissertation
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Electrodepostion of Iron Oxide on Steel Fiber for Improved Pullout Strength in Concrete

Description: Fiber-reinforced concrete (FRC) is nowadays extensively used in civil engineering throughout the world due to the composites of FRC can improve the toughness, flexural strength, tensile strength, and impact strength as well as the failure mode of the concrete. It is an easy crazed material compared to others materials in civil engineering. Concrete, like glass, is brittle, and hence has a low tensile strength and shear capacity. At present, there are different materials that have been employed … more
Date: August 2014
Creator: Liu, Chuangwei
Item Type: Refine your search to only Thesis or Dissertation

Electroencephalographic (EEG) biofeedback treatment for children with attention deficit disorders in a school setting.

Description: The purpose of this study was to explore the use of EEG biofeedback in a school setting to assist students who had attentional challenges. The equipment for implementing biofeedback was relatively inexpensive and was easily integrated into the school setting. Twenty students ranging in age from 7 to 17 were recruited for this study. Data was used from 14 subjects, 12 males (2 Hispanic, 1 African American, and 10 Caucasian) and 2 females (1 Hispanic, 1 Caucasian.) The subject pool was reduced du… more
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Date: December 2001
Creator: Mosse, Leah Kathryn
Item Type: Refine your search to only Thesis or Dissertation
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Electroencephalographic Events During the Wisconsin Card Sorting Test

Description: Quantitative electroencephalography (QEEG) was used in this study to describe cognitive processing, particularly brain locations used, during performance of the Wisconsin Card Sorting Test (WCST). The hypothesis was that significant cognitive functioning is not limited to the frontal lobes. Significant EEG activity was found in non-frontal areas as well as frontal areas.
Date: August 1998
Creator: DeBeus, Mary
Item Type: Refine your search to only Thesis or Dissertation
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Electrolysis of Aluminum Solutions in a Magnetic Field

Description: This investigation is an attempt to verify the original work done by George Antonoff and Anne Rowley, and to contribute specific data on the action of a magnetic field on aluminum cells. Experiments of the type they have described have been performed and an extensive set of data has been collected. It was thought that if the results of Antonoff and Rowley could be duplicated, further investigation would be warranted. However, the experiments have produced negative results. These results are des… more
Date: May 1950
Creator: Wood, Charles E.
Item Type: Refine your search to only Thesis or Dissertation
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Electromagnetic Aftereffects of Near-Death Experiences

Description: Study investigating electromagnetic effects among near-death experiencers (NDErs), people who reported a close brush with death without an NDE, and people who reported never having been close to death but who used their most life-changing event as a past reference point.
Date: Winter 2008
Creator: Mouri, Farnoosh M. & Holden, Janice Miner
Item Type: Refine your search to only Article
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