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Physical Sciences and Mathematics Commons

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Theses/Dissertations

William & Mary

Chemistry

2018

Articles 1 - 8 of 8

Full-Text Articles in Physical Sciences and Mathematics

Computational Investigations Of The Structure And Spectroscopy Of Small Biomolecules In The Gas Phase, Zachary Michael Smith Jul 2018

Computational Investigations Of The Structure And Spectroscopy Of Small Biomolecules In The Gas Phase, Zachary Michael Smith

Dissertations, Theses, and Masters Projects

Small biomolecule systems were interrogated using infrared multiple photon dissociation (IRMPD) action spectroscopy and corresponding quantum chemical calculations with a particular focus on peptide fragmentation and protonation site preference. b2+ and b3+ fragment ions with a terminal lysine homolog residue were investigated using IRMPD in the fingerprint region (1000 cm-1 – 2000 cm-1) and a variety of computational methods. We present the first spectroscopic confirmation of b-ion formation with a lactam structure. Infrared spectra for b2+ fragment system indicate the presence of a mixture of structures, though final determination will require further investigation. The b3+ fragment ion infrared spectra show …


Iron Polypyridyl Catalysts Assembled On Metal Oxide Semiconductors For Heterogeneous Photocatalytic Hydrogen Generation, Nicholas Race Apr 2018

Iron Polypyridyl Catalysts Assembled On Metal Oxide Semiconductors For Heterogeneous Photocatalytic Hydrogen Generation, Nicholas Race

Dissertations, Theses, and Masters Projects

Artificial Photosynthesis (AP) provides a promising method for the conversion of solar energy to chemical fuel in the form of H2 and O2. Development of heterogeneous systems in which H2 evolution catalysts are immobilized on metal oxide semiconductors is imperative for the large-scale implementation of AP systems. This research focuses on the immobilization of an active H2 evolution catalyst on large band gap semiconductors for the development and optimization of a highly active photocatalytic H2 generation system.


Surface-Enhanced Raman Spectroscopy Studies Of Organic Dyes For Art Conservation And Ph Sensing Applications, Shelle Nicholle Butler Apr 2018

Surface-Enhanced Raman Spectroscopy Studies Of Organic Dyes For Art Conservation And Ph Sensing Applications, Shelle Nicholle Butler

Dissertations, Theses, and Masters Projects

Surface-enhanced Raman scattering (SERS) spectroscopy is a powerful analytical technique with widespread applications. In this work, SERS applications in the realms of art conservation and biosensing are reviewed. First, the theory of this unambiguous and ultrasensitive technique is explained. Next, a review of the pedagogical journey in art conservation research through the lenses of undergraduates is offered in Chapter 2, a chapter recently submitted to the American Chemical Society. Finally, an investigation in biosensing SERS is explored with developing a SERS pH sensitive probe while offering new insight into SERS capabilities and the relationship between analyte and nanoparticle.


Ratiometric Fluorescent Sensors In Aqueous Environments, Matthew August Mccarron Apr 2018

Ratiometric Fluorescent Sensors In Aqueous Environments, Matthew August Mccarron

Dissertations, Theses, and Masters Projects

Conjugated polymer nanoparticles (CPN) doped with a mercury sensitive dye are able to detect ion concentrations as low as a parts-per-billion within an aqueous environment. Select forms of spirolatam rhodamine dye are capable of selectively undergoing a ring-opening reaction in response to Hg2+ ions. The initial closed form presents as a colorless, non-fluorescent, compound while the opened form results in a colored and highly fluorescent form. The CPNs are also fluorescent, yet at a lower wavelength and can transfer of their energy into the dye molecules via Förster resonance energy transfer. The dye’s reaction with Hg2+ goes unhindered by the …


Effect Of Pigment Volume Concentration On Physical And Chemical Properties Of Acrylic Emulsion Paints Assessed Using Single-Sided Nmr, Mary Therese Rooney Apr 2018

Effect Of Pigment Volume Concentration On Physical And Chemical Properties Of Acrylic Emulsion Paints Assessed Using Single-Sided Nmr, Mary Therese Rooney

Dissertations, Theses, and Masters Projects

Acrylic emulsion paint is one of the most common media employed by 20th century painters. Since early acrylic paintings have begun to require the attention of conservators, scientists are working to characterize the properties of these paints to facilitate conservation efforts. In this study, we report an investigation of the physical and chemical properties of acrylic emulsion paints using single-sided NMR in conjunction with gloss measurements and scanning electron microscopy coupled with energy dispersive spectrometry. Combining the data from these techniques gives insight into pigment-binder interactions and the acrylic curing process, showing that as pigment concentration is increased in paints, …


Radiation Shielding Bricks For Mars Using Martian Regolith Simulant And Hydrogen-Rich Polymers, Sara Sargent Jan 2018

Radiation Shielding Bricks For Mars Using Martian Regolith Simulant And Hydrogen-Rich Polymers, Sara Sargent

Dissertations, Theses, and Masters Projects

Radiation shielding materials are an essential component of long-term space travel and habitation. The mission to Mars will require a radiation shielding material that can be produced on Mars through energy and cost-efficient means. in this study, Martian regolith simulant and hydrogen-rich polymers are used to create a radiation shielding material in the form of bricks. The bricks are capable of shielding against galactic cosmic radiation on Mars. There are three methods in which the bricks were formed: 1) a heated press, 2) a microwave oven in a CO2 atmosphere, and 3) a vacuum oven with a low CO2 pressure. …


Development Of A One Pot [4+2]/R[4+2] 2-Pyridone Synthesis And The Fluorescence Of 2-Pyridone Azafluorenones, Nicholas Angello Jan 2018

Development Of A One Pot [4+2]/R[4+2] 2-Pyridone Synthesis And The Fluorescence Of 2-Pyridone Azafluorenones, Nicholas Angello

Dissertations, Theses, and Masters Projects

We report the concise synthesis of several tricyclic 2-pyridones via a one pot sequence involving an aldol condensation, alkene isomerization, intramolecular Diels-Alder cycloaddition, and selective retro-Diels-Alder cycloreversion. The starting materials are synthesized in one step from cheap and commercially available precursors. The intermediate [2.2.2]diazabicycloalkene cycloadducts can be isolated. The retro-Diels-Alder occurs at easily accessible temperatures due to base acceleration. Simple derivatization of the tricyclic products afforded azafluorenones with unprecedented fluorescent activity due to the pyridone motif.


Monitoring Infection Of E. Coli By Bacteriophage T7 Through Mass Spectrometry-Based Proteomics, Amy Swayne Schienschang Jan 2018

Monitoring Infection Of E. Coli By Bacteriophage T7 Through Mass Spectrometry-Based Proteomics, Amy Swayne Schienschang

Dissertations, Theses, and Masters Projects

Mass spectrometry-based proteomics has become an important and versatile tool in analytical chemistry, making sense of complex biological samples and shedding light on the intricate proteomes of living organisms. Bottom-up proteomics studies are used to elucidate the changes in gene expression of bacteriophage T7 over the course of infection of Escherichia coli. E. coli cultures were infected with T7, sampled over time, and proteins were isolated and enzymatically digested. Nanoflow liquid chromatography combined with tandem mass spectrometry was used to detect proteolytic peptides and identify host and phage proteins. Generally, phage proteins were detected on a time scale fitting the …