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Articles 1 - 14 of 14
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Development Of Reductive Metal Systems For The Degradation Of Energetic Compounds (Tatp, Tnt, And Rdx), Rebecca L. Albo
Development Of Reductive Metal Systems For The Degradation Of Energetic Compounds (Tatp, Tnt, And Rdx), Rebecca L. Albo
Electronic Theses and Dissertations
Triacetone triperoxide (TATP), a cyclic peroxide explosive, is frequently used by terrorists and amateur chemists due to the ease of synthesis and the availability of reagents. TATP is extremely sensitive to shock, heat, and friction thus a safe and rapid method for treating TATP is needed. The major objective of this dissertation was to develop in situ methodologies that could safely degrade TATP in various field situations. Initial studies focused on using zero-valent metals and mechanically alloyed metals to decompose TATP samples in both aqueous and organic solutions. The metal systems tested included zero-valent iron, magnesium, and magnesium bimetal, Mg/Pd. …
Novel Improvements On The Analytical Chemistry Of Polycyclic Aromatic Hydrocarbons And Their Metabolites, Wang Huiyong
Novel Improvements On The Analytical Chemistry Of Polycyclic Aromatic Hydrocarbons And Their Metabolites, Wang Huiyong
Electronic Theses and Dissertations
Polycyclic aromatic hydrocarbons (PAH) are important environmental pollutants originating from a wide variety of natural and anthropogenic sources. Because many of them are highly suspect as etiological agents in human cancer, chemical analysis of PAH is of great environmental and toxicological importance. Current methodology for PAH follows the classical pattern of sample preparation and chromatographic analysis. Sample preparation preconcentrates PAH, simplifies matrix composition, and facilitates analytical resolution in the chromatographic column. Among the several approaches that exist to pre-concentrate PAH from water samples, the Environmental Protection Agency (EPA) recommends the use of solid-phase extraction (SPE). High-performance liquid chromatography (HPLC) and …
Design, Synthesis And Characterization Of New Two-Photon Absorbing (2pa) Fluorescent Dyes And Bioconjugates, And Their Applications In Bioimaging, Carolina D. Andrade
Design, Synthesis And Characterization Of New Two-Photon Absorbing (2pa) Fluorescent Dyes And Bioconjugates, And Their Applications In Bioimaging, Carolina D. Andrade
Electronic Theses and Dissertations
The development of new multiphoton absorbing materials has attracted the attention of researchers for the last two decades. The advantages that multiphoton absorbing materials offer, versus their one-photon absorbing counterparts, rely on the nature of the nonlinearity of the absorption process, where two photons are absorbed simultaneously offering increased 3D resolution, deeper penetration, and less photobleaching and photodamage as a result of a more confined excitation. The applications of efficient two-photon absorbing materials have been extensively expanding into the fields of photodynamic therapy, microscopy, and optical data storage. One of the fields where an increased interest in multiphoton absorbing materials …
Black Writing Ink Analysis By Direct Infusion Electrospray Mass Spectroscopy, Christopher M. Moody
Black Writing Ink Analysis By Direct Infusion Electrospray Mass Spectroscopy, Christopher M. Moody
Electronic Theses and Dissertations
An optimized method of extraction, an instrumental analysis method and data analysis was proposed for black writing inks based on direct infusion electrospray-mass spectrometry (ESI-MS). The sampling and analysis method is both minimally destructive and able to assess differences in inks from a reference collection of thirty ballpoint, gel, and rollerball inks. The methanol extracts of ink on paper samples were analyzed with three direct infusion (ESI-MS) methods. Each method varied scan voltage negative and positive, ESI fragmentor applied voltage (+120V, +0V, and -120V), and mobile phase additive. Direct infusion ESI-MS analysis, followed by pair-wise comparisons of the observed ion …
The Fabrication Of Polymer-Derived Sicn/Sibcn Ceramic Nanostructures And Investigation Of Their Structure-Property Relationship, Sourangsu Sarkar
The Fabrication Of Polymer-Derived Sicn/Sibcn Ceramic Nanostructures And Investigation Of Their Structure-Property Relationship, Sourangsu Sarkar
Electronic Theses and Dissertations
Polymer-derived Ceramics (PDCs) represent a unique class of high-temperature stable materials synthesized directly by the thermal decomposition of polymers. This research first focuses on the fabrication of high temperature stable siliconcarbonitride (SiCN) fibers by electrospinning for ceramic matrix composite (CMC) applications. Ceraset™ VL20, a commercially available liquid cyclosilazane, was functionalized with aluminum sec-butoxide in order to be electrospinnable. The surface morphology of the electrospun fibers was investigated using the fibers produced from solvents. The electrospun fibers produced from the chloroform/N,N-dimethylformamide solutions had hierarchical structures that led to superhydrophobic surfaces. A “dry skin” model was proposed to explain the formation of …
Fabrication Of Functional Nanostructures Using Polyelectrolyte Nanocomposites And Reduced Graphene Oxide Assemblies, Anindarupa Chunder
Fabrication Of Functional Nanostructures Using Polyelectrolyte Nanocomposites And Reduced Graphene Oxide Assemblies, Anindarupa Chunder
Electronic Theses and Dissertations
A wide variety of nanomaterials ranging from polymer assemblies to organic and inorganic nanostructures (particles, wires, rods etc) have been actively pursued in recent years for various applications. The synthesis route of these nanomaterials had been driven through two fundamental approaches - 'Top down' and 'Bottom up'. The key aspect of their application remained in the ability to make the nanomaterials suitable for targeted location by manipulating their structure and functionalizing with active target groups. Functional nanomaterials like polyelectrolyte based multilayered thin films, nanofibres and graphene based composite materials are highlighted in the current research. Multilayer thin films were fabricated …
Polarization Dependent Two-Photon Absorption Properties Of Chiral Molecules, Carlos Toro
Polarization Dependent Two-Photon Absorption Properties Of Chiral Molecules, Carlos Toro
Electronic Theses and Dissertations
Molecules that are non-superimposable on their mirror image are named chiral or optically active compound. Over the years, molecular chirality has played an essential role in the understanding of fundamental aspects associated the origin of life, drug and food technologies and, asymmetric catalysis, among others. Moreover, most of the groundbreaking discoveries and advances made in this field have happened due to the development of spectroscopic techniques based on the natural asymmetry of the enantiomers and their ability to preferentially absorb right or left polarized light. For instance, circular dichroism (CD), which measures the difference in absorption between these two states …
Simulation Of Photochromic Compounds Using Density Functional Theory Methods, Pansy Patel
Simulation Of Photochromic Compounds Using Density Functional Theory Methods, Pansy Patel
Electronic Theses and Dissertations
This Thesis describes the systematic theoretical study aimed at prediction of the essential properties for the functional organic molecules that belong to diarylethene (DA) family of compounds. Diarylethenes present the distinct ability to change color under the influence of light, known as photochromism. This change is due to ultrafast chemical transition from open to closed ring isomers (photocyclization). It can be used for optical data storage, photoswitching, and other photonic applications. In this work we apply Density Functional Theory methods to predict 6 of the related properties: (i) molecular geometry; (ii) resonant wavelength; (iii) thermal stability; (iv) fatigue resistance; (v) …
Dft Study Of Geometry And Energetics Of Transition Metal Systems, Satyender Goel
Dft Study Of Geometry And Energetics Of Transition Metal Systems, Satyender Goel
Electronic Theses and Dissertations
This dissertation focuses on computational study of the geometry and energetics small molecules and nanoclusters involving transition metals (TM). These clusters may be used for various industrial applications including catalysis and photonics. Specifically, in this work we have studied hydrides and carbides of 3d-transition metal systems (Sc through Cu), small nickel and gold clusters. Qualitatively correct description of the bond dissociation is ensured by allowing the spatial and spin symmetry to break. We have tested applicability of new exchange-correlation functional and alternative theoretical descriptions (spin-contamination correction in broken symmetry DFT and ensemble Kohn-Sham (EKS)) as well. We studies TM hydrides …
Determining The Presence Of An Ignitable Liquid Residue In Fire Debris Samples Utilizing Target Factor Analysis, Kelly Mchugh
Determining The Presence Of An Ignitable Liquid Residue In Fire Debris Samples Utilizing Target Factor Analysis, Kelly Mchugh
Electronic Theses and Dissertations
Current fire debris analysis procedure involves using the chromatographic patterns of total ion chromatograms, extracted ion chromatograms, and target compound analysis to identify an ignitable liquid according to the American Society for Testing and Materials (ASTM) E 1618 standard method. Classifying the ignitable liquid is accomplished by a visual comparison of chromatographic data obtained from any extracted ignitable liquid residue in the debris to the chromatograms of ignitable liquids in a database, i.e. by visual pattern recognition. Pattern recognition proves time consuming and introduces potential for human error. One particularly difficult aspect of fire debris analysis is recognizing an ignitable …
Laboratory Studies To Field Evaluation : Remediation Of Polychlorinated Biphenyl Contaminated Painted Surfaces Through The Use Of Activated Metal Treatment Systems, Erin Kristen Saitta
Laboratory Studies To Field Evaluation : Remediation Of Polychlorinated Biphenyl Contaminated Painted Surfaces Through The Use Of Activated Metal Treatment Systems, Erin Kristen Saitta
Electronic Theses and Dissertations
Polychlorinated Biphenyls (PCBs) are a group of 209 congeners that are regulated under the Toxic Substance Control Act. They enter the environment as a result of industrial processes and can travel long distances. PCBs are environmentally persistent and bioaccumulate in animal populations. Painted surfaces are a common point source for PCBs and there are few options for remediating structures painted with PCB-contaminated paint. Removal of the paint can often spread contamination and disposing or burning of large structures is expensive. Experiments employing reductive dehalogenation through the use of a bimetal have shown that PCBs can be degraded in mild laboratory …
Synthesis And Applications Of Ring Opening Metathesis Polymerization Based Functional Block Copolymers, Sanchita Biswas
Synthesis And Applications Of Ring Opening Metathesis Polymerization Based Functional Block Copolymers, Sanchita Biswas
Electronic Theses and Dissertations
Ring opening metathesis polymerization (ROMP) is established as one of the efficient controlled living polymerization methods which have various applications in polymer science and technology fields. The research presented in this dissertation addresses several applications of multifunctional well-defined norbornene-based block copolymers synthesized by ROMP using ruthenium-based Grubbs catalysts. These novel block copolymers were applied to stabilize maghemite nanoparticles, creating the superparamagnetic polymeric nanocomposites. The Jaggregation properties of the porphyrin dyes were improved via self-assembly with a customized norbornene polymer. Novel multimodal copolymer probes were synthesized for two-photon fluorescence integrin-targeted bioimaging. In Chapter 1 a brief overview of ROMP along with …
Physicochemical And Thermochemical Properties Of Sulfonated Poly(Etheretherketone) Electrolyte Membranes, Stephen Rhoden
Physicochemical And Thermochemical Properties Of Sulfonated Poly(Etheretherketone) Electrolyte Membranes, Stephen Rhoden
Electronic Theses and Dissertations
Fuel cells have long been seen as an alternative to combustion powered and diesel powered engines and turbines. Production of energy via a fuel cell conversion method can generate up to 60% efficiency in comparison to 30% using a combustion powered engine, with low co-production of harmful side-products. The polymer electrolyte membrane (PEM) adapted for the fuel cell application is one of the main components that determines the overall efficiency. This research project was focused towards novel PEMs, such as sulfonated poly(etheretherketone) or SPEEK, which are cost-efficient and robust with high proton conductivities under hydrated conditions. The degree of sulfonation …
Statistical Analysis Of Visible Absorption Spectra And Mass Spectra Obtained From Dyed Textile Fibers, Katie Margaret White
Statistical Analysis Of Visible Absorption Spectra And Mass Spectra Obtained From Dyed Textile Fibers, Katie Margaret White
Electronic Theses and Dissertations
The National Academy of Sciences recently published a report which calls for improvements to the field of forensic science. Their report criticized many forensic disciplines for failure to establish rigorously-tested methods of comparison, and encouraged more research in these areas to establish limitations and assess error rates. This study applies chemometric and statistical methods to current and developing analytical techniques in fiber analysis. In addition to analysis of commercially available dyed textile fibers, two pairs of dyes are selected based for custom fabric dyeing on the similarities of their absorbance spectra and dye molecular structures. Visible absorption spectra for all …