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Chemical Analysis, Databasing, And Statistical Analysis Of Smokeless Powders For Forensic Application, Dana-Marie Dennis
Chemical Analysis, Databasing, And Statistical Analysis Of Smokeless Powders For Forensic Application, Dana-Marie Dennis
Electronic Theses and Dissertations
Smokeless powders are a set of energetic materials, known as low explosives, which are typically utilized for reloading ammunition. There are three types which differ in their primary energetic materials; where single base powders contain nitrocellulose as their primary energetic material, double and triple base powders contain nitroglycerin in addition to nitrocellulose, and triple base powders also contain nitroguanidine. Additional organic compounds, while not proprietary to specific manufacturers, are added to the powders in varied ratios during the manufacturing process to optimize the ballistic performance of the powders. The additional compounds function as stabilizers, plasticizers, flash suppressants, deterrents, and opacifiers. …
Synthesis Of Fluorene-Based Derivatives, Characterization Of Optical Properties And Their Applications In Two-Photon Fluorescence Imaging And Photocatalysis, Grace Githaiga
Electronic Theses and Dissertations
The two-photon absorption (2PA) phenomenon has attracted attention from various fields ranging from chemistry and biology to optics and engineering. Two of the common NLO applications in which organic materials have been used are three-dimensional (3D) fluorescence imaging and optical power limiting. Two-photon absorbing materials are, therefore, in great demand to meet the needs of emerging technologies. Organic molecules show great promise to meet this need as they can be customized through molecular engineering, and as the development of two-photon materials that suit practical application intensifies, so does research to meet this need. However, there remains some uncertainty in the …
Fabrication And Study Of Graphene-Based Nanocomposites For Sensing And Energy Storage, Matthew Mcinnis
Fabrication And Study Of Graphene-Based Nanocomposites For Sensing And Energy Storage, Matthew Mcinnis
Electronic Theses and Dissertations
Graphite is an allotrope of carbon made up of atomically thin sheets, each covalently bound together, forming a π-conjugated network. An individual layer, called graphene, has extraordinary electrical, thermal and physical properties that provide the opportunity for innovating new functional composites. Graphene can be produced directly on a metallic substrate by chemical vapor deposition or by chemical oxidation of graphite, forming a stable aqueous suspension of graphene oxide (GO), which allows for convenient solution processing techniques. For the latter, after thermal or chemical reduction, much of the properties of the starting graphene re-emerge due to the reestablishment of π-conjugation. The …
Development Of A Nano-Sensing Approach And A Portable Prototype For Real-Time Detection And Quantification Of Free Mercury In Stream-Flow: Combining Science And Engineering In Pro Of The Environment, Warinya Chemnasiri
Electronic Theses and Dissertations
Mercury (Hg) is a well-known hazardous environmental contaminant existing in several forms, but all are toxic to human in one way or the others. Since Hg usually settles into water polluting the environment and accumulating in living organisms, it is crucial to monitor Hg levels in the aquatic ecosystem. Although there are many well established techniques currently used to detect Hg, most of them require elaborate and time-consuming sample preparation and pre-concentration procedures, as well as costly and bulky equipment that limit their practical application in the field. In order to overcome the existent limitations in Hg determination methods, Hernandez …
Optimization Of Molecular Beacon-Based Multicomponent Probes For Analysis Of Nucleic Acids, Maria Stancescu
Optimization Of Molecular Beacon-Based Multicomponent Probes For Analysis Of Nucleic Acids, Maria Stancescu
Electronic Theses and Dissertations
Detection of single nucleotide substitutions (SNS) in DNA and RNA has a growing importance in biology and medicine. One traditional approach for recognition of SNS takes advantage of hybridization probes that bind target nucleic acids followed by measuring ?Tm, the difference in melting temperatures of matched and mismatched hybrids. The approach enables SNS differentiation at elevated temperatures (usually 40-65oC) often only in a narrow range of < 10oC and requires high-resolution melting devices. Here we demonstrate that a specially designed DNA probe (X sensor) can broaden ?Tm from ~10oC to ~16oC and distinguish SNS in the interval of ~5-40oC. Therefore, there is no need for heating or measuring Tm for accurate SNS differentiation. Our data indicate that this wide differentiation range is in part due to the non-equilibrium hybridization conditions. Further we explored the idea that it is possible to improve the performance of an X sensor operable in close to equilibrium conditions by shifting its operability to non-equilibrium conditions. One way to achieve this is to introduce as many as possible structured ligands in analyte's dissociated state. Here we show that by introducing the maximum possible conformational constraints in X probe it is possible to shift its operation to non-equilibrium conditions and to improve its selectivity at temperatures < 15oC. Thus, this work points towards a new strategy for the design of highly selective hybridization sensors which operate in non-equilibrium conditions at close to room temperature. The X sensors could be utilized in qPCR, microarrays, as well as RNA analysis in living cells and for ambient temperature point-of-care diagnostics. In the last part of this work, X sensors were used in real time detection of PCR products. The sensors were optimized to operate in PCR buffer with optimal Mg2+ concentration. They were able to detect the target amplicon together with nonspecific products. The results presented here suggest that X sensors might be adopted for real time PCR format.
Synthesis, Linear And Nonlinear Photophysical Characterization Of Two Symmetrical Pyrene-Terminated Squaraine Derivatives In Solution, Alfonso Ballestas Barrientos
Synthesis, Linear And Nonlinear Photophysical Characterization Of Two Symmetrical Pyrene-Terminated Squaraine Derivatives In Solution, Alfonso Ballestas Barrientos
Electronic Theses and Dissertations
Two indole-based squaraine dyes bonded to two pyrenyl groups through vinyl- and ethynyl- linkers were synthesized with the aim of enhancing the intramolecular charge transfer interaction in addition to improving their optical properties. The absorption and emission properties of these derivatives were determined in order to gain an insight into the intensity of this type of interaction, their aggregation behavior and compare them with results obtained through quantum chemical calculations. Both compounds presented high photochemical stability in THF, and the linear spectroscopic characterization revealed high extinction coefficients, large fluorescence quantum yields and relatively low tendency of forming excimers in several …
Strategies For Enhanced Genetic Analysis Of Trace Dna From Touch Dna Evidence And Household Dust, Katherine Farash
Strategies For Enhanced Genetic Analysis Of Trace Dna From Touch Dna Evidence And Household Dust, Katherine Farash
Electronic Theses and Dissertations
In forensic casework it is often necessary to obtain genetic profiles from crime scene samples that contain increasingly smaller amounts of genetic material, called Low Template DNA (LTDNA). Two examples of LTDNA sources are touch DNA evidence and dust bunnies. Touch DNA refers to DNA that is left behind through casual contact of a donor with an object or another person. Touch DNA can be used to prove a suspect was present at a crime scene. Dust bunnies, or dust conglomerates, typically contain trapped shed skin cells of anyone in the vicinity along with fibers, dirt, hair, and other trace …
Investigating New Guaiazulenes And Diketopyrropyrroles For Photonic Applications, Ebrahim Ghazvini Zadeh
Investigating New Guaiazulenes And Diketopyrropyrroles For Photonic Applications, Ebrahim Ghazvini Zadeh
Electronic Theses and Dissertations
?-Conjugated systems have been the focus of study in recent years in order to understand their charge transport and optical properties for use in organic electronic devices, fluorescence bioimaging, sensors, and 3D optical data storage (ODS), among others. As a result, several molecular building blocks have been designed, allowing new frontiers to be realized. While various successful building blocks have been fine-tuned at both the electronic and molecular structure level to provide advanced photophysical and optoelectronic characteristics, the azulene framework has been under-appreciated despite its unique electronic and optical properties. Among several attributes, azulenes are vibrant blue naturally occurring hydrocarbons …
Photophysics Of Organic Probes And Their Applications In Bioimaging & Photodynamic Therapy, Bosung Kim
Photophysics Of Organic Probes And Their Applications In Bioimaging & Photodynamic Therapy, Bosung Kim
Electronic Theses and Dissertations
Over the past several decades the phenomenon of luminescence (divided into fluorescence and phosphorescence) has received great attention in the field of biological science. This quest has motivated scientists for a variety of applications, including fluorescence imaging. Fluorescence microscopy techniques that provide unique advantages, such as high spatial resolution and superior sensitivity, have been regarded as attractive tools in biophotonics. With the progress of ultrafast laser sources, two-photon absorption (2PA), in which a molecule absorbs two photons simultaneously, has opened possibilities of using it for various applications. Two-photon fluorescence microscopy (2PFM), which affords deeper tissue penetration and excellent three-dimensional (3D) …
Folate Conjugated Hyperbranched Polyester Nanoparticles For Prostate Tumor-Targeted Delivery Of A Cytotoxic Peptide Via Prostate Specific Membrane Antigen, Orielyz Flores-Fernandez
Folate Conjugated Hyperbranched Polyester Nanoparticles For Prostate Tumor-Targeted Delivery Of A Cytotoxic Peptide Via Prostate Specific Membrane Antigen, Orielyz Flores-Fernandez
Electronic Theses and Dissertations
Prostate Cancer is the second most deadly cancer in men, after lung cancer. The need for new and effective therapeutics that can constrain prostate cancer progression are challenged by the lack of suitable delivery strategies that target prostate cancer tissue. To study CT20p as potential chemotherapeutic agent in the treatment of prostate cancer we proposed the use of targetable hyperbranched polyester (HBPE) based nanoparticles as delivery system. Folic acid was conjugated to the nanocarrier to improve the selectivity of the nanoparticle towards specific cell surface targets in prostate cancer cell lines. Specifically we evaluated LNCaP that up-regulated the PSMA receptor. …
Structure-Property Relationship Of The Two-Photon Circular Dichroism Of Compounds With Axial And Helical Chirality, Carlos Diaz
Structure-Property Relationship Of The Two-Photon Circular Dichroism Of Compounds With Axial And Helical Chirality, Carlos Diaz
Electronic Theses and Dissertations
Back in 1894 Lord Kelvin coined the term "chiral" in order to refer to molecules whose mirror images were not superimposable with themselves. Over the years, research has demonstrated the important role that chiral molecules play in life, chemistry, and biology as well as their importance in the development of new drugs and technologies. The efforts to understand chiral systems have been mainly driven by spectroscopic methods that leverage on the opposite responses that enantiomers have to linear or circularly polarized light of both handedness. More specifically, Electronic Circular Dichroism (ECD) which measures the differences in linear absorption of left …
Quantum Chemical Studies For The Engineering Of Metal Organic Materials, Hector Javier Rivera Jacquez
Quantum Chemical Studies For The Engineering Of Metal Organic Materials, Hector Javier Rivera Jacquez
Electronic Theses and Dissertations
Metal Organic Materials (MOM) are composed of transition metal ions as connectors and organic ligands as linkers. MOMs have been found to have high porosity, catalytic, and optical properties. Here we study the gas adsorption, color change, and non-linear optical properties of MOMs. These properties can be predicted using theoretical methods, and the results may provide experimentalists with guidance for rational design and engineering of novel MOMs. The theory levels used include semi-empirical quantum mechanical calculations with the PM7 Hamiltonian and, Density Functional Theory (DFT) to predict the geometry and electronic structure of the ground state, and Time Dependent DFT …
Synthesis And Characterization Of New Probes For Use In Fluorescence And X-Ray Ct Bioimaging, Simon Tang
Synthesis And Characterization Of New Probes For Use In Fluorescence And X-Ray Ct Bioimaging, Simon Tang
Electronic Theses and Dissertations
The pursuit of more suitable drugs intended for possible biological applications are a continuously growing topic of research within the scientific community. One of these suitable qualities includes the need for hydrophilicity and or some appropriate delivery system for the drug to enter into biological systems. A system of analyzing and following these compounds would then, however, be necessary to conduct any kind of mechanistic or interaction studies for he said drug within the biological system. Just to name a few, fluorescence and X-ray computed tomography (CT) methods allow for imaging of biological systems but require the need of compounds …
Quantitative Assessment Of The Effects Of Microbial Degradation Of A Simple Hydrocarbon Mixture, Jessica Kindell
Quantitative Assessment Of The Effects Of Microbial Degradation Of A Simple Hydrocarbon Mixture, Jessica Kindell
Electronic Theses and Dissertations
Ignitable liquids consist of either a single organic compound or a complex organic mixture. In regards to fire debris analysis, the analyst is responsible for determining if an ignitable liquid residue is present. However, when extracted from soil-containing fire debris evidence, chemical degradation from microorganisms is observed to result in the loss of compounds based on chemical structure. It can also happen when the evidence container is stored at room temperature before analysis. This can present a challenge to the fire debris analyst when identifying and classifying the ignitable liquid residue based on the criteria established by standard test methods. …
Aggregation Of Squaraine Dye Derivatives In Solid State Spin-Coated Thin Films, Mohammed Daoudi
Aggregation Of Squaraine Dye Derivatives In Solid State Spin-Coated Thin Films, Mohammed Daoudi
Electronic Theses and Dissertations
Squaraine dyes have been the subject of intensive studies due their unusual electronic properties that make them good candidates for a wide range of applications in various technological fields. They are particularly promising in nonlinear optics, bioimaging for labeling and sensing of biomolecules, as sensitizers for solar energy harvesting in solar cells and organic photovoltaics, two-photon absorbing materials, near-infrared (NIR) emitting fluorescent probes, second harmonic generation organic dyes, and sensitizers for photodynamic therapy among others. In this dissertation, the aggregation behaviors and features of several squaraine dye derivatives in solid state thin films were studied and reported. In the first …
Mass Spectral Studies To Investigate Butylbenzene Fragmentation Pathway And Pyrolysis Products., Balasubramaniam Lingam
Mass Spectral Studies To Investigate Butylbenzene Fragmentation Pathway And Pyrolysis Products., Balasubramaniam Lingam
Electronic Theses and Dissertations
In this dissertation research, two fundamental studies involving gas chromatography mass spectrometry of n-butylbenzene and pyrolysis products are presented. In the first study, fragmentation pathways of n-butylbenzene in quadrupole ion trap have been investigated. At low energy, product ion corresponding to m/z 92 and m/z 91 are formed via competitive parallel dissociation. Studies have also shown that at higher energy m/z 92 has sufficient internal energy to undergo further fragmentation yielding m/z 91 via consecutive dissociation. Thus in order to discern the fragmentation pathways of n-butylbenzene, the technique of two-dimensional correlation spectroscopy (2DCOS) was applied to the mass spectral data. …
Forensic Application Of Chemometric Analysis To Visible Absorption Spectra Collected From Dyed Textile Fibers, Alejandra Flores
Forensic Application Of Chemometric Analysis To Visible Absorption Spectra Collected From Dyed Textile Fibers, Alejandra Flores
Electronic Theses and Dissertations
Forensic analysis of evidence consists of the comparison of physical, spectroscopic, or chemical characteristics of a questioned sample to a set of knowns. Currently, decisions as to whether or not the questioned sample can be associated or grouped with the knowns are left up to the discretion of the forensic analyst. The implications of these outcomes are presented as evidence to a jury in a court of law to determine if a defendant is guilty of committing a crime or not. Leading up to, and since, the publication of the National Academy of Sciences (NAS) report entitled “Strengthening Forensic Science …
Improvements On Instrumentation To Explore The Multidimensionality Of Luminescence Spectroscopy, Anthony Moore
Improvements On Instrumentation To Explore The Multidimensionality Of Luminescence Spectroscopy, Anthony Moore
Electronic Theses and Dissertations
This dissertation presents experimental and instrumentation developments that take full advantage of the multidimensional nature of line narrowing spectroscopy at liquid nitrogen (77 K) and liquid helium (4.2 K) temperatures. The inconvenience of sample freezing procedures is eliminated with the aid of cryogenic fiber optic probes. Rapid collection of multidimensional data formats such as wavelength time matrices, excitation emission matrices, time-resolved excitation emission matrices and time resolved excitation emission cubes is made possible with the combination of a pulsed tunable dye laser, a spectrograph and an intensifier-charged coupled device. These data formats provide unique opportunities for processing vibrational luminescence data …