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Fluorescence Spectroscopy And Microscopy Studies Of Chromophore Coupling In Isolated Small Molecule Nanostructures, Sarah R. Marques Oct 2019

Fluorescence Spectroscopy And Microscopy Studies Of Chromophore Coupling In Isolated Small Molecule Nanostructures, Sarah R. Marques

Doctoral Dissertations

My thesis focused on understanding the structural changes producing different spectral signatures seen in aggregates of 7,8,15,16- tetrazaterrylene (TAT). Recent work from our group showed crystallographically selective directional charge-separation within isolated extended TAT crystals without the need of an interface. Aggregates of different size not only exhibited different exciton recombination kinetics, but different spectral signatures. The motivation for understanding the change in the structural properties producing the unique spectral signatures is elucidating the mechanism of this directional charge-separation, intrinsic or extrinsic. In this case, an intrinsic mechanism means it is caused by molecular design and packing, and extrinsic mechanism means …


Protein Detection And Structural Characterization By Mass Spectrometry Using Supramolecular Assemblies And Small Molecules, Bo Zhao Oct 2019

Protein Detection And Structural Characterization By Mass Spectrometry Using Supramolecular Assemblies And Small Molecules, Bo Zhao

Doctoral Dissertations

Mass spectrometry (MS) has played an increasingly prominent role in proteomics and structure biology because it shows superior capabilities in identification, quantification and structural characterization of proteins. To realize its full potential in protein analysis, significant progress has been made in developing innovative techniques and reagents that can couple to MS detection. This dissertation demonstrates the use of polymeric supramolecular assemblies for enhanced protein detection in complex biological mixtures by MS. An amphiphilic random co-polymer scaffold is developed to form functional supramolecular assemblies for protein/ peptide enrichment. The influences of charge density and functional group pKa on host-guest interactions …


Top-Down And Bottom-Up Fabrication Of Key Components In Miniature Energy Storage Devices, Wenhao Li Oct 2019

Top-Down And Bottom-Up Fabrication Of Key Components In Miniature Energy Storage Devices, Wenhao Li

Doctoral Dissertations

The advent of miniature electronic devices demands power sources of commensurate form factors. This spurs the research of micro energy storage devices, e.g., 3D microbatteries. A 3D microbattery contains nonplanar microelectrodes with high aspect ratio and high surface area, separated by a nanoscale electrolyte. The device takes up a total volume as small as 10 mm3, allowing it to serve on a chip and to provide power in-situ. The marriage of nanotechnology and electrochemical energy storage makes microbattery research a fascinating field with both scientific excitement and application prospect. However, successful fabrication of well-functioned key components …


Model-Form Uncertainty Quantification For Predictive Probabilistic Graphical Models, Jinchao Feng Oct 2019

Model-Form Uncertainty Quantification For Predictive Probabilistic Graphical Models, Jinchao Feng

Doctoral Dissertations

In this thesis, we focus on Uncertainty Quantification and Sensitivity Analysis, which can provide performance guarantees for predictive models built with both aleatoric and epistemic uncertainties, as well as data, and identify which components in a model have the most influence on predictions of our quantities of interest. In the first part (Chapter 2), we propose non-parametric methods for both local and global sensitivity analysis of chemical reaction models with correlated parameter dependencies. The developed mathematical and statistical tools are applied to a benchmark Langmuir competitive adsorption model on a close packed platinum surface, whose parameters, estimated from quantum-scale computations, …


Reactive And Stimuli-Responsive Sulfonium-Based Polymer Zwitterions, Cristiam Santa Chalarca Jul 2019

Reactive And Stimuli-Responsive Sulfonium-Based Polymer Zwitterions, Cristiam Santa Chalarca

Doctoral Dissertations

This dissertation describes the synthesis and characterization of novel monomers and (co)polymer zwitterions that incorporate trialkylsulfonium cations. The novel materials presented herein constitute a unique type of polymer zwitterions that exhibit salt- and temperature-dependent water solubility as well as inherent reactivity. The behavior of these polymers in aqueous solutions, as nanostructures, and at liquid-liquid interfaces was studied; in all cases, the inherent reactivity of the polymers was harnessed towards the fabrication of novel polymers and soft materials. Following an introductory chapter, Chapter 2 describes the synthesis of sulfonium sulfonate monomers and polymer zwitterions. Both styrenic and methacrylic monomers were synthesized …


Synthesis Of Magnetic Ion Doped Ii-Vi Benzenechalcogenolate Molecular Clusters, Fumitoshi Kato Jul 2019

Synthesis Of Magnetic Ion Doped Ii-Vi Benzenechalcogenolate Molecular Clusters, Fumitoshi Kato

Doctoral Dissertations

Diluted magnetic semiconductor quantum dots (DMS-QDs) is a class of material prepared by introducing a small percentage of magnetic impurities to impart new magneto-optical properties to the host nanocrystal (NC). Such materials are regarded as promising candidates for their potential application in spintronic devices. The overall functionality of the DMS‑QD is highly dependent on the dopant position within the host structure. A thorough understanding of the doping mechanism is, therefore, critical to gain better control over the dopant speciation in nanocrystal lattice and material properties. In this work, we utilized II‑VI molecular clusters that are analogous to bulk semiconductors as …


Modulating Dopant-Defect Interactions In Transition Metal Doped Colloidal Strontium Titanate Nanocrystals, William Harrigan Jul 2019

Modulating Dopant-Defect Interactions In Transition Metal Doped Colloidal Strontium Titanate Nanocrystals, William Harrigan

Doctoral Dissertations

Perovskites such as strontium titanate, a wide band gap semiconductor have been widely studied due to the multitude of potential applications in photocatalysis, multiferroics, sensing, and microelectronics. Various novel optical, electrical and magnetic properties can be imparted through the introduction of different transition metal dopant ions. The introduction of these impurities has been shown to impart functionality for various applications. The use of Cr3+has been shown to introduce defect levels into the band structure of SrTiO3and increase visible light utilization for photocatalysis. Transition metal doped highly crystalline colloidal SrTiO3nanocrystals (NC) were synthesized using two …


Modification Of 2d Materials Utilizing Functional Polymer Interfacial Layers, Ryan Selhorst Jul 2019

Modification Of 2d Materials Utilizing Functional Polymer Interfacial Layers, Ryan Selhorst

Doctoral Dissertations

This dissertation describes the modification of 2D transition metal dichalcogenides (TMDCs). These materials exhibit unique electronic properties, ranging from metallic to insulating, and can transport either electrons (n-type) or holes (p-type). Polymers containing electronically-active moieties offer a path to control the electronic properties of a 2D material without altering the inherent structure of the semiconductor. This dissertation focuses on the synthesis of polymers bearing chalcogen-rich or zwitterionic moieties to alter the electronic and solution properties of 2D materials. Chapter 2 describes polymers containing sulfur-rich tetrathiafulvalene (TTF) and their effects as electroactive coatings on the TMDC molybdenum disulfide (MoS2). …


Enhanced Mass Spectrometric Analysis Of Peptides And Proteins Using Polymeric Reverse Micelles, Mahalia Adelina Corazon Paningbatan Serrano Mar 2019

Enhanced Mass Spectrometric Analysis Of Peptides And Proteins Using Polymeric Reverse Micelles, Mahalia Adelina Corazon Paningbatan Serrano

Doctoral Dissertations

Mass spectrometry (MS) has become a key and indispensable tool in the identification, characterization, and quantitative analysis of proteins owing to its universality, sensitivity, specificity, and its capability for multiplexed detection. Because biological samples containing these protein analytes are almost always complex systems, various techniques are employed in conjunction with MS to fully harness its analytical potential and enhance its detection capabilities. This dissertation explores the use of amphiphilic polymeric reverse micelles in enriching proteins and peptides from complex biological mixtures and in enhancing their mass spectrometric analysis. Fundamental studies that elucidate the molecular basis for the observed MS signal …


Synthesis And Molecular Transport Studies In Zeolites And Nanoporous Membranes, Vivek Vattipalli Mar 2019

Synthesis And Molecular Transport Studies In Zeolites And Nanoporous Membranes, Vivek Vattipalli

Doctoral Dissertations

The advent of nanoporous materials such as zeolites and nanoporous membranes has provided cost-effective solutions to some of the most pressing problems of the 20th century such as the conversion of crude oil into fuels and valuable chemicals. Hierarchical zeolites and mesoporous inorganic membranes are showing great promise in addressing new problems such as the conversion of biomass into value-added chemicals and development of energy-efficient separation processes. The synthesis and fundamental aspects of molecular transport in these new materials with hierarchical porosities need to be better understood in order to rationally develop them for these desired applications. Pore narrowing …


Precipitation And Coacervation In Polyelectrolyte-Colloid Systems, Fatih Comert Mar 2019

Precipitation And Coacervation In Polyelectrolyte-Colloid Systems, Fatih Comert

Doctoral Dissertations

Complex coacervation between oppositely charged polyelectrolytes (PEs) and colloids (i.e. micelles and proteins) has increasingly become popular due to the use of these materials in a range of applications including but not limited to personal care, biomaterials, protein purification, and food science. In taking advantage of complex coacervation, which is a liquid-liquid phase separation, precipitation has always represented a problem by introducing inhomogeneities, irreversibility and irreproducible kinetics. Therefore, understanding the dominant factors driving the formation of precipitates is important to control outcomes. In this work, we have performed comparative studies of coacervation and precipitation in model PE-colloid systems to investigate …


Design And Self-Assembly Of Responsive Scaffolds For Food And Sensing Applications, Uma Sridhar Mar 2019

Design And Self-Assembly Of Responsive Scaffolds For Food And Sensing Applications, Uma Sridhar

Doctoral Dissertations

Developing an understanding of how molecules, materials and complex systems contribute to biological functions is important since the interpretation of such mechanisms paves the way to further the development of materials that replicate natural functions or impart the observed properties to synthetic materials. The self-assembly of stimuli-responsive scaffolds based on micelles, liposomes, hydrogels and thin films has been of considerable interest. These systems need to be endowed with certain design features which influence the self-assembly and the responsiveness of the scaffold when subjected to external stimuli which could be physical, chemical or biological in nature. This kind of insight is …


Amphiphilic Assemblies With Responsive Characteristics At Surfaces And Interfaces, Piyachai Khomein Mar 2019

Amphiphilic Assemblies With Responsive Characteristics At Surfaces And Interfaces, Piyachai Khomein

Doctoral Dissertations

Amphiphilic self-assembly has gained a lot of interest in both academic and industrial fields. Amphiphiles have a unique ability to self-assemble in water, providing a range of nanosized materials of various morphologies. Many efforts have been dedicated to developing responsive amphiphilic assemblies by introducing responsive characteristics into the amphiphile building blocks. Responsive assemblies have been utilized in many promising applications such as targeted drug delivery systems, smart sensors, and electronic devices. Here, we reported four different types of responsive assemblies created via the incorporation of different responsive groups either at the material’s surface or interface. To achieve the responsive characteristics …