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Design and Fabrication of Nanostructures for the Enhancement of Photovoltaic Devices
Get PDFIn 2012 the net world electricity generation was 21.56 trillion kilowatt hours. Photovoltaics only accounted for only 0.1 trillion kilowatt hours, less than 1 % of the total power. Recently there has been a push to convert more energy production to renewable sources. In recent years a great deal of interest has been shown for dye sensitized solar cells. These devices use inexpensive materials and have reported efficiencies approaching 12% in the lab. Here methods have been studied to improve upon these, and other, devices. Different approaches for the addition of gold nanoparticles to TiO2 films were studied. These additions acted as plasmonic and light scattering enhancements to reported dye sensitized devices. These nanoparticle enhancements generated a 10% efficiency in device performance for dye sensitized devices. Quantum dot (QD) sensitized solar cells were prepared by successive ionic layer adsorption and reaction (SILAR) synthesis of QDs in mesoporous films as well as the chemical attachment of colloidal quantum dots using 3-mercaptopropionic acid (3-MPA). Methods of synthesizing a copper sulfide (Cu2S) counter electrode were investigated to improve the device performance. By using a mesoporous film of indium tin oxide nanoparticles as a substrate for SILAR growth of Cu2S catalyst, an increase in device performance was seen over that of devices using platinum. These devices did suffer from construction drawbacks. This lead to the development of 3D nanostructures for use in Schottky photovoltaics. These high surface area devices were designed to overcome the recombination problems of thin film Schottky devices. The need to deposit a transparent top electrode limited the success of these devices, but did lead to the development of highly ordered metal nanotube arrays. To further explore these nanostructures depleted heterojunction devices were produced. Along with these devices a new approach to depositing lead sulfide quantum dots was developed. This electrophoretic deposition technique uses an applied electric field to deposit nanoparticles onto a substrate. This creates the possibility for a low waste method for depositing nanocrystals onto nanostructured substrates
Machine Learning based Protein Sequence to (un)Structure Mapping and Interaction Prediction
Get PDFProteins are the fundamental macromolecules within a cell that carry out most of the biological functions. The computational study of protein structure and its functions, using machine learning and data analytics, is elemental in advancing the life-science research due to the fast-growing biological data and the extensive complexities involved in their analyses towards discovering meaningful insights. Mapping of protein’s primary sequence is not only limited to its structure, we extend that to its disordered component known as Intrinsically Disordered Proteins or Regions in proteins (IDPs/IDRs), and hence the involved dynamics, which help us explain complex interaction within a cell that is otherwise obscured. The objective of this dissertation is to develop machine learning based effective tools to predict disordered protein, its properties and dynamics, and interaction paradigm by systematically mining and analyzing large-scale biological data.
In this dissertation, we propose a robust framework to predict disordered proteins given only sequence information, using an optimized SVM with RBF kernel. Through appropriate reasoning, we highlight the structure-like behavior of IDPs in disease-associated complexes. Further, we develop a fast and effective predictor of Accessible Surface Area (ASA) of protein residues, a useful structural property that defines protein’s exposure to partners, using regularized regression with 3rd-degree polynomial kernel function and genetic algorithm. As a key outcome of this research, we then introduce a novel method to extract position specific energy (PSEE) of protein residues by modeling the pairwise thermodynamic interactions and hydrophobic effect. PSEE is found to be an effective feature in identifying the enthalpy-gain of the folded state of a protein and otherwise the neutral state of the unstructured proteins. Moreover, we study the peptide-protein transient interactions that involve the induced folding of short peptides through disorder-to-order conformational changes to bind to an appropriate partner. A suite of predictors is developed to identify the residue-patterns of Peptide-Recognition Domains from protein sequence that can recognize and bind to the peptide-motifs and phospho-peptides with post-translational-modifications (PTMs) of amino acid, responsible for critical human diseases, using the stacked generalization ensemble technique. The involved biologically relevant case-studies demonstrate possibilities of discovering new knowledge using the developed tools
The Blanket of the Dark
Get PDFThe Blanket of the Dark is a psychological thriller that explores the horrors of postpartum psychosis, a rare but serious illness a new mother can experience in the days and weeks following the birth of her child. The film is an intimate portrayal of the psychology of a new mother suffering from the hallucinations and delusions that are symptoms of this horrific and oftentimes undiagnosed illness. In the end, motherhood for women with undiagnosed postpartum psychosis is anything but joyful, and can lead to suicide and murder.
This paper is a candid analysis, a production report as it were, of the making of my thesis film, The Blanket of the Dark. I will begin with an introduction to how The Blanket of the Dark came to be, and then dive into a detailed plot analysis along with “behind-the-scenes” accounts of my thoughts and experiences on screenwriting, preproduction, production and postproduction process. All documents used during production are included in the appendix. I hope that future filmmakers will read my about my journey and know that, while filmmaking is one of the most challenging experiences anyone can have and questions about their talents and merits may arise, the insecurities and perceived impossibilities are hurdles that any filmmaker can overcome
The 773rd Tank Destroyer Battalion at the Falaise Pocket, 1944: The Application of Tank Destroyer Doctrine in the Field
Get PDFDuring World War II, the United States Army employed a new weapon on the battlefield in an attempt to defeat German armor tactics: the tank destroyer. Tank Destroyer Force was created to stem the tide of German armored attacks and form an opening for American tanks to make their own counter-attacks. Since the end of the war, tank destroyer battalions have been regarded as a failed experiment, despite the evidence that they effectively did their jobs. The negative feedback in the immediate post-war period lead to the dissolution of the Tank Destroyer Force. Many of the studies of tank destroyers focus on the doctrine they followed and the faults in it. However, most of the studies do not look at the successful application of tank destroyer doctrine in the field by tank destroyer battalions. This paper will examine operations of the 773rd Tank Destroyer Battalion and its application of tank destroyer doctrine during the Battle of Chambois from August 17-21, 1944, for which it won a Presidential Unit Citation
Synthesis and Analysis of LaNi1-xMxO2 (M = Cu, Co) Possible Analog for Superconducting Cuprate
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