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Quantum-Confined CdS Nanoparticles on DNA Templates

Description: As electronic devices became smaller, interest in quantum-confined semiconductor nanostructures increased. Self-assembled mesoscale semiconductor structures of II-VI nanocrystals are an especially exciting subject because of their controllable band gap and unique photophysical properties. Several preparative methods to synthesize and control the sizes of the individual nanocrystallites and the electronic and optical properties have been intensively studied. Fabrication of patterned nanostructur… more
Date: May 1998
Creator: Rho, Young Gyu
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries

Microstructure and Electronic Structures of Er-Doped Si Nano-particles Synthesized by Vapor Phase Pyrolysis

Description: Si nanoparticles are new prospective optoelectronic materials. Unlike bulk Si cry-stals, Si nanoparticles display intriguing room-temperature photoluminescence. A major challenge in the fabrication of Si nanoparticles is the control of their size distribution. The rare-earth element Er has unique photo emission properties, including low pumping power, and a temperature independent, sharp spectrum. The emission wavelength matches the transmission window of optical fibers used in the telecommunic… more
Access: Restricted to UNT Community Members. Login required if off-campus.
Date: May 2000
Creator: Chen, Yandong
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Polymer hydrogel nanoparticles and their networks

Description: The thermally responsive hydroxypropyl cellulose (HPC) hydrogel nanoparticles have been synthesized and characterized. The HPC particles were obtained by chemically crosslinking collapsed HPC polymer chains in water-surfactant (dodecyltrimethylammonium bromide) dispersion above the lower critical solution temperature (LCST) of the HPC. The size distributions of microgel particles, measured by dynamic light scattering, have been correlated with synthesis conditions including surfactant concen… more
Date: August 2002
Creator: Lu, Xihua
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries

Interfacial Electrochemistry of Metal Nanoparticles Formation on Diamond and Copper Electroplating on Ruthenium Surface

Description: An extremely facile and novel method called spontaneous deposition, to deposit noble metal nanoparticles on a most stable form of carbon (C) i.e. diamond is presented. Nanometer sized particles of such metals as platinum (Pt), palladium (Pd), gold (Au), copper (Cu) and silver (Ag) could be deposited on boron-doped (B-doped) polycrystalline diamond films grown on silicon (Si) substrates, by simply immersing the diamond/Si sample in hydrofluoric acid (HF) solution containing ions of the correspon… more
Access: Restricted to the UNT Community Members at a UNT Libraries Location.
Date: May 2003
Creator: Arunagiri, Tiruchirapalli Natarajan
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Determination of critical length scales for corrosion processes using microelectroanalytical techniques.

Description: A key factor in our ability to produce and predict the stability of metal-based macro- to nano-scale structures and devices is a fundamental understanding of the localized nature of corrosion. Corrosion processes where physical dimensions become critical in the degradation process include localized corrosion initiation in passivated metals, microgalvanic interactions in metal alloys, and localized corrosion in structurally complex materials like nanocrystalline metal films under atmospheric and… more
Date: March 1, 2004
Creator: Zavadil, Kevin Robert & Wall, Frederick Douglas
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Synthesis and characterization of crystalline assembly of poly Nisopropylacry-lamide)-co-acrylic acid nanoparticles.

Description: In this study, crystalline poly(N-isopropylacrylamide-co-acrylic acid) (PNIPAm-co-AAc) nanoparticle network in organic solvents was obtained by self assembling precursor particles in acetone/epichlorohydrin mixture at room temperature followed by inter-sphere crosslinking at ~98 °C. The crystals thus formed can endure solvent exchanges or large distortions under a temporary compressing force with the reoccurrence of crystalline structures. In acetone, the crystals were stable, independent of te… more
Date: December 2004
Creator: Zhou, Bo
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Functionalized nanoparticles for sensor applications.

Description: We will describe our work on functionalized arrays of nanoparticles crosslinked with short conducting molecules that contain sensing functionalities. These bridging ligands modulate their conductivity based on their interaction with analytes. This functionalized nanoparticles organic ligand composite material once it is assembled between nanogaps electrodes will provide nanosized sensors that can be easily interrogated. These nanogap sensors will be engineered so that they can be fabricated int… more
Date: September 1, 2005
Creator: Simonson, Robert Joseph; Childs, Kenton David; Howell, Stephen Wayne; Dirk, Shawn M. & Wheeler, David Roger
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Assembling semiconductor nanocomposites using DNA replication technologies.

Description: Deoxyribonucleic acid (DNA) molecules represent Nature's genetic database, encoding the information necessary for all cellular processes. From a materials engineering perspective, DNA represents a nanoscale scaffold with highly refined structure, stability across a wide range of environmental conditions, and the ability to interact with a range of biomolecules. The ability to mass-manufacture functionalized DNA strands with Angstrom-level resolution through DNA replication technology, however, … more
Date: November 1, 2005
Creator: Heimer, Brandon W.; Crown, Kevin K. & Bachand, George David
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department

Synthesis and Characterization of Crystalline Assemblies of Functionalized Hydrogel Nanoparticles

Description: Two series monodispersed nanoparticles of hydroxylpropyl cellulose (HPC) and functionalized poly-N-isopropylamide (PNIPAM) particles have been synthesized and used as building blocks for creating three-dimensional networks, with two levels of structural hierarchy. The first level is HPC nanoparticles were made from methacrylated or degradable cross-linker attached HPC. These nanoparticles could be stabilized at room temperature by residual methacrylate or degradable groups are present both with… more
Access: Restricted to UNT Community Members. Login required if off-campus.
Date: December 2005
Creator: Cai, Tong
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Edge energies and shapes of nanoprecipitates.

Description: In this report we present a model to explain the size-dependent shapes of lead nano-precipitates in aluminum. Size-dependent shape transitions, frequently observed at nanolength scales, are commonly attributed to edge energy effects. This report resolves an ambiguity in the definition and calculation of edge energies and presents an atomistic calculation of edge energies for free clusters. We also present a theory for size-dependent shapes of Pb nanoprecipitates in Al, introducing the concept o… more
Date: January 1, 2006
Creator: Hamilton, John C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Decomposition of contaminants using photochemically active nanoparticles.

Description: No Description Available.
Date: April 1, 2006
Creator: Zifer, Thomas; Kemp, Richard Alan (Sandia National Laboratories, Albuquerque, NM); Jennison, Dwight Richard (Sandia National Laboratories, Albuquerque, NM); Spangler, Scott W. (Sandia National Laboratories, Albuquerque, NM); Simmons, Blake Alexander; Morse, Daniel H. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Nanoparticles Engineered to Bind Serum Albumin: Microwave Assisted Synthesis, Characterization, and Functionalization of Fluorescently-Labeled, Acrylate-Based, Polymer Nanoparticles

Description: The potential use of polymeric, functionalized nanoparticles (NPs) as drug delivery vectors was explored. Covalent conjugation of albumin to the surface of NPs via maleimide chemistry proved problematic. However, microwave assisted synthesis of NPs was not only time efficient, but enabled the exploration of size control by changing the following parameters: temperature, microwave power, reaction time, initiator concentration, and percentage of monomer used. About 1.5 g of fluorescently-labe… more
Date: August 2010
Creator: Hinojosa, Barbara R.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Synthesis of Novel Organic Chromophores and Their Characterization

Description: Nonlinear organic liquids that exhibit two-photon absorption (TPA) function as good optical limiters for sensor protection from laser pulses. L34 (4-butyl-4'-propyl-diphenylethyne) is a liquid organic compound exhibiting nonlinear optical absorption. A thiol- derivatized analog of L34 (“thiol-L34”) was prepared to bind the molecules to the surface of gold nanoparticles. Surface binding is necessary to investigate synergy between nonlinear optical absorption of gold nanoparticles and thiol-L34. … more
Date: December 2014
Creator: Pokharel, Sundari D.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Deleterious Synergistic Effects of Concurrent Magnetic Field and Superparamagnetic (Fe3O4) Nanoparticle Exposures on CHO-K1 Cell Line

Description: While many investigations have been performed to establish a better understanding of the effects that magnetic fields and nanoparticles have on cells, the fundamental mechanisms behind the interactions are still yet unknown, and investigations on concurrent exposure are quite limited in scope. This study was therefore established to investigate the biological impact of concurrent exposure to magnetic nanoparticles and extremely-low frequency magnetic fields using an in-vitro CHO-K1 cell line mo… more
Date: May 2015
Creator: Coker, Zachary
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Self-assembly Polymeric Nanoparticles Composed of Polymers Crosslinked with Transition Metals for Use in Drug Delivery

Description: A major drawback of chemotherapy is the lack of selectively leading to damage in healthy tissue, which results in severe acute side effects to cancer patients. The use of nanoparticles as a drug delivery system has emerged as novel strategy to overcome the barriers of immunogenic response, controlled release of therapeutic, and targeting the toxicity only to cancerous cells. In this study, polymeric nanoparticles composed of transition metals and particles derived from natural biopolymers hav… more
Date: December 2015
Creator: Nguyen, Duong Thuy
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Enhancement of Light Emission from Metal Nanoparticles Embedded Graphene Oxide

Description: A fully oxidized state of graphene behaves as a pure insulating while a pristine graphene behaves as a pure conducting. The in-between oxide state in graphene which is the controlled state of oxide behaves as a semiconducting. This is the key condition for tuning optical band gap for the better light emitting property. The controlling method of oxide in graphene structure is known as reduction which is the mixed state of sp2 and sp3 hybrid state in graphene structure. sp2 hybridized domains cor… more
Date: May 2016
Creator: Karna, Sanjay K.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Applications of Metallic Clusters and Nanoparticles via Soft Landing Ion Mobility, from Reduced to Ambient Pressures

Description: Nanoparticles, simple yet groundbreaking objects have led to the discovery of invaluable information due to their physiological, chemical, and physical properties, have become a hot topic in various fields of study including but not limited to chemistry, biology, and physics. In the work presented here, demonstrations of various applications of chemical free nanoparticles are explored, from the determination of a non-invasive method for the study of the exposome via using soft-landing ion mobil… more
Date: August 2018
Creator: Aguilar Ayala, Roberto
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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