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Porous Materials as Drug Delivery Systems

Description: The porous materials discussed in this dissertation are metal-organic frameworks (MOFs) and porous liquids. Due to their high surface areas, tunable structures, and controllable porosities, MOFs have been explored for a wide variety of drug delivery applications. In chapter 2, MOFs have been used as magnetothermal-triggered release carriers through spatially distributed iron oxide nanoparticles within MOF matrix as a magnetic heating mediator and surface-grafted thermal-responsive nanocap as an… more
This item is restricted from view until January 1, 2028.
Date: December 2022
Creator: Ge, Xueying
Item Type: Refine your search to only Thesis or Dissertation

Porous Organic Polymer-based Nanotraps for Metal Resource Recovery/Extraction from Water

Description: The recovery processes of critical metals from multiple sources have turned more and more attention due to the increasing demand and consumption of them in modern industry. Many metals are used as significant components in manufacturing of a variety of products and equipment, playing significant roles in the economic security and national security; those metals involve rare earth elements (REEs), precious metals which include gold, silver, and platinum group metals (PGMs), and other valuable me… more
This item is restricted from view until June 1, 2025.
Date: May 2023
Creator: Song, Yanpei
Item Type: Refine your search to only Thesis or Dissertation
open access

Porphyrin and BODIPY Derived Donor-Acceptor Multi-Modular Systems: Synthesis, and Excited State Energy and Electron Transfer Studies

Description: This dissertation demonstrates that it is possible to create a donor-acceptor system that can transform sunlight into electrons. By using site-directed synthesis, it was possible to create a novel trans-A2B2 porphyrin. In the pursuit of creating a supramolecular system, both the novel (TPA-BT)2ZnP and C60imidazole combined in solution such that the nitrogenous lone pair of C60 imidazole would coordinate axially to the zinc atom in the porphyrin. The conjugates' characterization utilized spectra… more
Date: May 2022
Creator: Benitz, Alejandro Daniel
Item Type: Refine your search to only Thesis or Dissertation

Praseodymium Oxide and Organic Modified Cerium Oxide Nanoparticles for Electrodeposition of Nickel-Ceramic Nanocomposites to Enhance Corrosion Protection and Mechanical Properties

Description: There is a consistent need in many industries, especially oil and gas, to develop coatings which have higher corrosion resistance and better hardness to extend the lifetime of equipment when it is exposed to hostile environments. Electrodeposition has been a favorable method in the synthesis of metal coatings because of its low cost, convenience, ability to work at low temperatures, and ability to control surface morphology and structure. The inclusion of ceramic nanoparticles in metal matrix c… more
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Date: May 2019
Creator: Sanders, Stephen
Item Type: Refine your search to only Thesis or Dissertation
open access

Precipitation and Pattern Formation under Far-From-Equilibrium Conditions

Description: Precipitates of a series of alkaline earth metal (barium and strontium) carbonates, chromates, phosphates, and sulfates were formed at high supersaturation by diffusion through silica hydrogel, agarose hydrogel, and the freshly developed agarosesilica mixed gels. The reaction vessels could be a small test tube, a recently designed standard micro slide cassette and a enlarged supercassette. Homogeneous nucleation is thought to have taken place, and particle development led to the formation of an… more
Date: August 1995
Creator: Chen, Peng, 1960-
Item Type: Refine your search to only Thesis or Dissertation
open access

The Precipitation of Strontium Sulfate in Gels

Description: The growth of strontium sulfate precipitate by diffusion in various gels was studied by using optical transmission and confocal microscopies, scanning and transmission electron microscopies, and energy dispersive X ray fluorescence. Pure silica gel, pure agarose gel and the silica/agarose mixed gel at pH 7 - 10 were used throughout the present study. Precipitate morphology is sensitive to pH and to the nature of the growth medium. The morphology was observed as a function of time. The lack of c… more
Date: December 1991
Creator: Lee, Ya
Item Type: Refine your search to only Thesis or Dissertation
open access

Predicting Chemical and Biochemical Properties Using the Abraham General Solvation Model

Description: Several studies were done to illustrate the versatillity of the Abraham model in mathematically describing the various solute-solvent interactions found in a wide range of different chemical and biological systems. The first study focused on using the solvation model to construct mathematical correlations describing the minimum inhibitory concentration of organic compounds for growth inhibition towards the three bacterial strains Porphyromonas gingivalis, Selenomonas artemidis, and Streptococc… more
Date: May 2009
Creator: Mintz, Christina
Item Type: Refine your search to only Thesis or Dissertation

Preparation and characterization of praseodymium oxide films and powders.

Description: Nanocrystalline praseodymium oxide films have been successfully generated on stainless steel substrates. The electrochemical deposition was performed in the cathode compartment of a divided electrochemical cell with a regular three-electrode configuration. The green films obtained by electrodeposition were then annealed at high temperatures for 1-3 hours. X-ray diffraction revealed the fluorite structure of Pr6O11 and the crystallite size was calculated. X-ray photoelectron spectroscopy was emp… more
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Date: May 2004
Creator: Shang, Yajuan
Item Type: Refine your search to only Thesis or Dissertation
open access

The preparation and characterization of thermo-sensitive colored hydrogel film and surfactant-free porous polystyrene three-dimensional network.

Description: Polymer hydrogel films change their properties in response to environmental change. This remarkable phenomenon results in many potential applications of polymer hydrogel films. In this thesis colored thermo-sensitive poly(N-isopropylacrylamide) (PNIPAAm) hydrogel film was prepared by firstly synthesizing polymer latex and secondarily crosslinking the nanoparticles and casting the polymers onto glass. The shape-memory effect has been observed when changing the environmental temperature. The temp… more
Date: December 2001
Creator: Zhou, Bo
Item Type: Refine your search to only Thesis or Dissertation
open access

Preparation and Stereochemistry of Reactive Intermediates Containing a Silicon-Carbon Double Bond

Description: 1,1-Dimethyl-2-neopentylsilene reacted with the N-methylimine of benzophenone to give 1,2,2-trimethyl-3- neopentyl-4,4-diphenyl-l-aza-2-silacyclobutane, I, and 2,3,4,4a-tetrahydro-2,3,3-trimethyl-1-phenyl-4-neopentyl-2- aza-3-silanephthalene, II, in 35% and 20% yields, respectively. Compounds I and II did not serve as thermal silene precursors. Heating I and II to over 280°C did not yield 1,3-disilacyclobutanes. In the presence of 2,3- dimethyl-1,3-butadiene typical silene products were not obt… more
Date: December 1991
Creator: Uang, Shinian
Item Type: Refine your search to only Thesis or Dissertation
open access

Preparation of flat dendrimers and polycyclic aromatic hydrocarbons connected via 1,3,5-triethynylbenzene core.

Description: Flat dendrimers, consisting of a hexavalent aromatic core and rigid ethynyl units locked in place by ether connections were developed based upon the divergent synthetic method. Alternating functional groups were adopted on each site of the hexa-substituted benzene, in order to avoid undesired cyclization pathways. The flat structures of conjugated dendrimers would allow investigation on the discotic liquid crystal properties. In addition, these ethylnyl dendrimers are expected to show directed … more
Date: December 2008
Creator: Jung, Jiyoung
Item Type: Refine your search to only Thesis or Dissertation
open access

Preparation of N-Substituted Hydroxylamines from Oxaziridines

Description: In many series of compounds, intensity of biological activity and chemical reactivity are proportional. Generally whenever a alkyl group replaces a reactive hydrogen atom, as would be the case for an N-substituted hydroxylamine as compared to hydroxylamine, the over-all biological activity of the resulting compound is lower than that of its nonalkylated analogue. Since toxicity and physiological activity are not proportional, this comparison can only suggest possible types of derivatives to p… more
Date: January 1968
Creator: Truitt, Sharon G.
Item Type: Refine your search to only Thesis or Dissertation
open access

The Preparation of Pyridinium Derivatives by the Knoevenagel Condensation

Description: An attempt is made in the work described in this paper to extend the series started by Hall and Platas by means of a Knoevenagel condensation between 3-hydroxy-1,4-naphtho-quinone-2-(4-methylpyridinium) anhydride and various aromatic aldehydes giving rise to a series of unsaturated substituents on the four position of the pyridine ring.
Date: May 1955
Creator: Miller, Eugene James
Item Type: Refine your search to only Thesis or Dissertation
open access

Preparation of Pyridinium Derivatives of 2,3-Dichloro-5(8?)-Nitro-1,4-Naphthoquinone

Description: This paper describes the preparation of pyridine derivatives of 2,3-dichloro-5(8?)-nitro-1,4-naphthoquinone. A method for the nitration of 2,3-dichloro-1,4-naphthoquinone is also described. Certain 4-n-alkyl, 3,4-dialkyl, and 4-cycloalkyl pyridine derivatives are caused to undergo condensation reactions with the nitrated naphthoquinone, giving rise to a series of compounds of the preceding type (X). All of the compounds prepared will be tested for anti-tubercular activity by Parke-Davis and Com… more
Date: 1955
Creator: Mahon, Frank
Item Type: Refine your search to only Thesis or Dissertation

Preparing and Using Hydrophobic Fluorinated Polymers for Corrosion Protection on Aluminum Substrate

Description: Corrosion is one of the most expensive failures in industries that used metal components and other construction materials. In fact, corrosion is responsible for hundreds of billions-dollar loss in the US alone each year. In general, corrosion occurs when metal surfaces are exposed to water, oxygen, acids, bases, or salts. Therefore, metal substrates must be protected by using materials that act as barriers to avoid destructive corrosion attack. Aluminum is one of the most common metals used in … more
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Date: May 2019
Creator: Yaseen, Waleed Khaleel
Item Type: Refine your search to only Thesis or Dissertation

Pressure Controlled Topochemical Polymerization in Two-Dimensional Hybrid Perovskite

Description: Mechanical pressure offers unique control over the energy landscape of chemical reactions, opening up pathways that are inaccessible through conventional thermochemistry. We hypothesize that the reduced dimensionality defines the conformational space of the high-pressure reaction, giving rise to new selectivity that is unavailable in 3D systems. Here, we demonstrate this concept through the pressure-controlled topochemical polymerization of the diacetylene molecule deca‐3,5‐diyn‐1‐amine (DDA) i… more
Date: December 2021
Creator: Abu-Amara, Lama Marwan
Item Type: Refine your search to only Thesis or Dissertation
open access

Pressure Effects on Electric Field Spectra of Molecular Rydberg States

Description: Electric field studies, electrochromism, were used to obtain excited-state data for analogous divalent sulfur compounds. The sulfides investigated were dimethyl sulfide and small cyclic sulfides including the three to six member ring compounds. The excited-state dipole moments and polarizabilities are reported for the first s, p, and d Rydberg absorption bands which occur in the near vacuum ultraviolet region from 230 to 170 nm. The excited-state data are interpreted in terms of the particular … more
Date: December 1982
Creator: Altenloh, Daniel Dean
Item Type: Refine your search to only Thesis or Dissertation
open access

Properties of Molecular Rydberg States

Description: Many of the bands in the vapor-phase far-ultraviolet absorption spectra of simple molecules can often be fit to mathematical progressions referred to as molecular Rydberg series. The name Rydberg arises from the similarity between the Rydberg formula for the atomic hydrogen spectrum and the formulae for the progressions found in molecular spectra. The theories of molecular Rydberg transitions and states are discussed in terms of the inferences that have been made in the past from the available … more
Date: December 1974
Creator: Scott, John Delmoth
Item Type: Refine your search to only Thesis or Dissertation
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