Controlled Depositions of Metal and Metal Cluster Ions by Surface Field Patterning in Soft-Landing Devices (open access)

Controlled Depositions of Metal and Metal Cluster Ions by Surface Field Patterning in Soft-Landing Devices

Patent relating to controlled deposition of metal and metal cluster ions by surface field patterning in soft-landing devices.
Date: April 19, 2011
Creator: Verbeck, Guido F. & Davila, Stephen
Object Type: Patent
System: The UNT Digital Library
Electrochemical Synthesis of Rare Earth Ceramic Oxide Coatings (open access)

Electrochemical Synthesis of Rare Earth Ceramic Oxide Coatings

This book chapter discusses the electrochemical synthesis of lanthanum, cerium, and praseodymium oxides.
Date: November 11, 2015
Creator: Golden, Teresa; Shang, Yajuan; Wang, Qi & Zhou, Ting
Object Type: Book Chapter
System: The UNT Digital Library
Regulation of Lactobacillic Acid Formation in Lactobacillus Plantarum (open access)

Regulation of Lactobacillic Acid Formation in Lactobacillus Plantarum

Cyclopropanation of the unsaturated fatty acid moieties of membrane phospholipids is a commonly observed phenomenon in a number of bacterial systems. The cyclopropane fatty acids are usually synthesized during and after the transition from exponential growth to stationary phase, or under such environmental conditions as acidic culture pH, low oxygen tension or high salt concentrations. S-Adenosylmethionine, the ubiquitous methyl group donor, provides the methylene bridge carbon in the reaction catalyzed by cyclopropane fatty acid synthase. Also formed in the reaction is S-adenosylhomocysteine, a potent inhibitor of cyclopropane fatty acid synthase, which is degraded by S-adenosylhomocysteine nucleosidase. This work provides evidence for at least two modes of regulation of lactobacillic acid synthesis, the cyclopropane fatty acid formed from cis-vaccenic acid (cis-11,12-octadecenoic acid), in Lactobacillus piantarum.
Date: December 1980
Creator: Smith, Darwin Dennis
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Formal oxo- and aza-[3 + 2] reactions of α-enaminones and quinones: a double divergent process and the roles of chiral phosphoric acid and molecular sieves (open access)

Formal oxo- and aza-[3 + 2] reactions of α-enaminones and quinones: a double divergent process and the roles of chiral phosphoric acid and molecular sieves

Article develops a double divergent process for the reaction of α-enaminones with quinones through facile manipulation of catalyst and additive, leading to structurally completely different products.
Date: September 21, 2020
Creator: Luo, Weiwei; Sun, Zhicheng; Fernando, E. H. Nisala; Nesterov, Vladimir N.; Cundari, Thomas R., 1964- & Wang, Hong
Object Type: Article
System: The UNT Digital Library
Effects of Different Concentrations of Poly(vinyl pyrrolidone) on the Solubility of Lamotrigine and Diazepam in Ethanol + Water Mixtures at 298.2 K (open access)

Effects of Different Concentrations of Poly(vinyl pyrrolidone) on the Solubility of Lamotrigine and Diazepam in Ethanol + Water Mixtures at 298.2 K

Article on the effects of different concentrations of poly(vinyl pyrrolidone) on the solubility of lamotrigine and diazepam in ethanol and water mixtures at 298.2 K.
Date: July 28, 2009
Creator: Soltanpour, Shahla; Acree, William E. (William Eugene) & Jouyban, Abolghasem
Object Type: Article
System: The UNT Digital Library
Silene Stereochemistry (open access)

Silene Stereochemistry

The reaction of tert-butyllithium with chloromethylphenylvinylsilane at low temperatures in hexane gave a 48% yield of a mixture of the five isomers of 1,3-dimethyl-1,3-diphenyl-2,4-dineopentyl-1,3-disilacyclobutane, formed by the head-to-tail dimerization of both E- and Z-1-methyl-1-phenyl-2-neopentylsilenes, along with an acyclic dimer. These were separated and their stereochemistry was established by ('1)H- and ('13)C-NMR spectroscopy. The E- and Z-silenes were also trapped as their {4 + 2} cycloadducts with cyclopentadiene, 2,3-dimethyl-1,3-butadiene and anthracene, which also were separated and stereochemically characterized. A consistent mole ratio of 70:30 for the E- and Z-silene adducts is interpreted as evidence for stereochemical induction in the silene generation reaction. It is also suggested that the dimerization of the silenes to give the 1,3-disilacyclobutanes occurs by a nonstereospecific stepwise pathway. When E- or Z-1-methyl-1-phenyl-2-neopentylsilene was generated by the retro-Diels-Alder flow vacuum thermolysis of its corresponding cyclopentadiene or anthracene adduct at temperatures between 400 and 600(DEGREES)C and then trapped with 2,3-dimethyl-1,3-butadiene, the stereochemical distribution of the products is independent of the stereochemistry of the silene precursor, indicating that the silene is not configurationally stable towards cis-trans isomerization at these temperatures. Evidence that the intermolecular ene reaction and the {4 + 2} cycloaddition which occur with 2,3-dimethyl-1,3-butadiene are concerted is presented. …
Date: August 1984
Creator: Lee, Myong Euy
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Targeted and Metal-loaded Polymeric Nanoparticles As Potential Cancer Therapeutics (open access)

Targeted and Metal-loaded Polymeric Nanoparticles As Potential Cancer Therapeutics

Polymeric nanoparticles were designed, synthesized, and loaded with metal ions to explore the therapeutic potential for transition metals other than platinum found in cisplatin. Nanoparticles were synthesized to show the potential for polymer based vectors. Metal loading and release were characterized via Inductively Coupled Plasma Mass Spectrometry (ICP MS), Energy Dispersive X-Ray Spectroscopy (EDX), X-Ray Photoelectron Spectroscopy (XPS), and Elemental Analysis. Targeting was attempted with the expectation of observed increased particle uptake by cancer cells with flow cytometry and fluorescence microscopy. Results demonstrated that a variety of metals could be loaded to the nano-sized carriers in an aqueous environment, and that the release was pH-dependent. Expected increased targeting was inconsistent. The toxicity of these particles was measured in cancer cells where significant toxicity was observed in vitro via dosing of high copper-loaded nanoparticles and slight toxicity was observed in ruthenium-loaded nanoparticles. No significant toxicity was observed in cells dosed with metal-free nanoparticles. Future research will focus on ruthenium loaded polymeric nanoparticles with different targeting ligands dosed to different cell lines for the aim of increased uptake and decreased cancer cell viability.
Date: May 2014
Creator: Harris, Alesha N.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Gold, Silver, and Copper Nanoparticles Stabilized in Biocompatible Aqueous Media (open access)

Gold, Silver, and Copper Nanoparticles Stabilized in Biocompatible Aqueous Media

Patent relating to gold, silver, and copper nanoparticles stabilized in biocompatible aqueous media.
Date: December 30, 2009
Creator: Omary, Mohammad A.; Hu, Zhibing; Marpu, Sreekar & Elbjeirami, Oussama
Object Type: Patent
System: The UNT Digital Library
Rediscovery of the Elements: Columbium and Tantalum (open access)

Rediscovery of the Elements: Columbium and Tantalum

Article describing the discovery of columbium and tantalum. Tourist information regarding locations significant to these discoveries are included.
Date: Summer 2013
Creator: Marshall, James L., 1940- & Marshall, Virginia R.
Object Type: Article
System: The UNT Digital Library
Improving the Selectivity of the C-C Coupled Product Electrosynthesis by Using Molecularly Imprinted Polymer-An Enhanced Route from Phenol to Biphenol (open access)

Improving the Selectivity of the C-C Coupled Product Electrosynthesis by Using Molecularly Imprinted Polymer-An Enhanced Route from Phenol to Biphenol

Authors of the article describe how they developed a procedure for selective 2,4-dimethylphenol, DMPh, direct electro-oxidation to 3,3' ,5,5'-tetramethyl-2,2'-biphenol, TMBh, a C-C coupled product. The authors claim that the procedure is reasonably selective towards TMBh without requiring harmful additives or elevated temperatures.
Date: October 12, 2023
Creator: Sudagar, Alcina Johnson; Shao, Shuai; Żołek, Teresa; Maciejewska, Dorota; Asztemborska, Monika; Cieplak, Maciej et al.
Object Type: Article
System: The UNT Digital Library
The Electrodeposition of Zinc (open access)

The Electrodeposition of Zinc

This thesis examines the use of zinc for electroplating and compares its use to other metals. Experiments conducted to gather data indicated circumstances which resulted in optimal results.
Date: August 1939
Creator: Flanagin, Charles E.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Purification of HMG-CoA Reductase and Regulation by Protein-Lipid Interactions (open access)

Purification of HMG-CoA Reductase and Regulation by Protein-Lipid Interactions

The enzyme 3-Hydroxy-3- Methylglutaryl Coenzyme A Reductase catalyzes the rate limiting step of hepatic cholesterol biosynthesis and is unique among the enzymes in the early part of the pathway in that it is membrane bound. This gives rise to potential regulation of the enzyme through interactions with the endoplasmic reticulum membrane. A purification procedure has been developed which consistently produces enzyme of high specific activity. In order to fully characterize the interactions between HMG-CoA reductase and the lipids in its immediate environment, HMG-CoA reductase was purified to homogeneity and shown to be a protein-lipid complex.
Date: December 1982
Creator: Brent, Lynn G. (Lynn Gran)
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Advanced modeling of materials with PAOFLOW 2.0: New features and software design (open access)

Advanced modeling of materials with PAOFLOW 2.0: New features and software design

This article describes the recent re-design of the code and the new features and improvements in performance of PAOFLOW, a software tool that constructs tight-binding Hamiltonians from self-consistent electronic wavefunctions by projecting onto a set of atomic orbitals.
Date: September 2, 2021
Creator: Cesaroli, Frank T.; Supka, Andrew; Jayaraj, Anooja; Costa, Marcio; Siloi, Ilaria; Sławińska, Jagoda et al.
Object Type: Article
System: The UNT Digital Library
GC/MS Analysis of Chlorinated Organic Compounds in Municipal Wastewater After Chlorination (open access)

GC/MS Analysis of Chlorinated Organic Compounds in Municipal Wastewater After Chlorination

A study has been conducted for the qualitative and Quantitative analysis of chlorinated organic compounds in water. The study included the adaptation of Amberlite XAD macroreticular resin techniques for the concentration of municipal wastewater samples, followed by GC/MS analysis. A new analytical method was developed for the determination of volatile halogenated organics using liquid-liquid extraction and electron capture gas chromatography. And, a computer program was written which searches raw GC/MS computer files for halogen-containing organic compounds.
Date: August 1982
Creator: Henderson, James E. (James Edward)
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Selectivity and Mechanism of Hydrogen Atom Transfer by an Isolable Imidoiron (III) Complex (open access)

Selectivity and Mechanism of Hydrogen Atom Transfer by an Isolable Imidoiron (III) Complex

This article discusses a mechanistic study of hydrogen atom transfer by an isolable iron (III) imido complex, LᴹᵉFeNAd (Lᴹᵉ = bulky β-diketiminate ligand, 2,4-bis(2,6-diisopropylphenylimido)pentyl; Ad = 1-adamantyl).
Date: May 12, 2011
Creator: Cowley, Ryan E.; Eckert, Nathan A.; Vaddadi, Sridhar; Figg, Travis M.; Cundari, Thomas R., 1964- & Holland, Patrick L.
Object Type: Article
System: The UNT Digital Library
Synthesis and Characterization of Two and Three Coordinate Gold (I) Conjugated and Rigid Metallodendrimers (open access)

Synthesis and Characterization of Two and Three Coordinate Gold (I) Conjugated and Rigid Metallodendrimers

This dissertation is a study of two major topics that involve synthetic strategies for new classes of phosphorescent gold(I)-based metallodendrimers. The phosphorescence of organic and inorganic luminophores originates from spin-orbit coupling owing to internal or external heavy atom effects as well as metal-centered emissions. Previous work in the Omary group entailed systematically designed small molecules, metallopolymers, and unconjugated metallodendrimers that contain d10 and d8 metals, whereas this dissertation aims in part to expand such strategies to the conjugated metallodendrimer regime. In one approach novel synthetic strategies were used to make first-generation phenyl acetylene dendrimers and phosphine derivatives thereof. The phosphine dendrimers are made by tethering one of the phosphines to an unsaturated dendrimer, as such phosphine dendrimers are better chromophores and luminophores due to their structural rigidity and extended conjugation. In another approach, 2- and 3-coordinate Au(I) dendritic complexes are synthesized from these phosphine dendrimers. This study is further extended to study metallodendritic complexes with different cores, for example triphenylene-based metallodendritic complexes with six acetylene branches. The physical properties of the metallodendrimers can be modulated upon proceeding to further dendrimer generations or by using solubilizing groups on the peripheral phosphines, thus allowing better processability for thin-film fabrication as required for …
Date: August 2012
Creator: Kaipa, Ushasree
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Shining Light on Chitosan: A Review on the Usage of Chitosan for Photonics and Nanomaterials Research (open access)

Shining Light on Chitosan: A Review on the Usage of Chitosan for Photonics and Nanomaterials Research

This article highlights the different molecular-nano systems that are prepared or stabilized using the Chitosan polymer.
Date: June 17, 2018
Creator: Marpu, Sreekar & Benton, Erin N.
Object Type: Article
System: The UNT Digital Library
The Spin-Forbidden Reaction of Ground State Sulfur Atoms with Ethylene (open access)

The Spin-Forbidden Reaction of Ground State Sulfur Atoms with Ethylene

This article examines ground-state S-atoms generated by pulsed laser photolysis of OCS precursor, and monitored by time-resolved resonance fluorescence.
Date: January 25, 2016
Creator: Thompson, Kristopher; Gao, Yide & Marshall, Paul
Object Type: Article
System: The UNT Digital Library
An Attempt to Produce a High Octane Gasoline from C4 Hydrocarbons (open access)

An Attempt to Produce a High Octane Gasoline from C4 Hydrocarbons

This thesis presents the results of an experiment conducted to discover if selenic acid or monazite sand are possible catalysts that can be used for the alkylation of isobutane and isobutene.
Date: June 1939
Creator: Scott, Howard Winfred
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Chemical Toxicity Correlations for Several Fish Species Based on the Abraham Solvation Parameter Model (open access)

Chemical Toxicity Correlations for Several Fish Species Based on the Abraham Solvation Parameter Model

Article on chemical toxicity correlations for several fish species based on the Abraham solvation parameter model.
Date: September 1, 2005
Creator: Hoover, Kaci R.; Acree, William E. (William Eugene) & Abraham, M. H. (Michael H.)
Object Type: Article
System: The UNT Digital Library
Controlling Topological States in Topological/Normal Insulator Heterostructures (open access)

Controlling Topological States in Topological/Normal Insulator Heterostructures

This article contains a systematic investigation of the nature of the nontrivial interface states in topological/normal insulator (TI/NI) heterostructures.
Date: November 26, 2018
Creator: Costa, Marcio; Costa, Antônio T.; Freitas, Walter A.; Schmidt, Tome M.; Buongiorno Nardelli, Marco & Fazzio, Adalberto
Object Type: Article
System: The UNT Digital Library
A Dark Adaptation Study of College Men and Women (open access)

A Dark Adaptation Study of College Men and Women

This study is the result of tests conducted to determine the adaptability of the human eye to darkness.
Date: August 1940
Creator: Henry, Archie
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Development of Neutral Red as a pH/pCO2 Luminescent Sensor for Biological Systems (open access)

Development of Neutral Red as a pH/pCO2 Luminescent Sensor for Biological Systems

This article demonstrates for the first time that Neutral Red (NR) can also serve as a CO2 sensor, because of NR’s unique optical properties, which change with dissolved carbon dioxide (dCO2) concentrations. In this article optical sensitivity of NR was quantified as a function of changes in absorption and emission spectra to dCO2 in a pH 7.3 buffer medium at eight dCO2 concentrations.
Date: August 5, 2021
Creator: Ericson, Megan N.; Shankar, Sindhu K.; Chahine, Laya M.; Omary, Mohammad A.; Hunt von Herbing, Ione & Marpu, Sreekar
Object Type: Article
System: The UNT Digital Library
Aluminum and Copper Chemical Vapor Deposition on Fluoropolymer Dielectrics and Subsequent Interfacial Interactions (open access)

Aluminum and Copper Chemical Vapor Deposition on Fluoropolymer Dielectrics and Subsequent Interfacial Interactions

This study is an investigation of the chemical vapor deposition (CVD) of aluminum and copper on fluoropolymer surfaces and the subsequent interfacial interactions.
Date: December 1997
Creator: Sutcliffe, Ronald David
Object Type: Thesis or Dissertation
System: The UNT Digital Library