Physical Sciences and Mathematics Commons^™

Microcavity Enhanced Raman Scattering, Benjamin James Petrak

USF Tampa Graduate Theses and Dissertations

Raman scattering can accurately identify molecules by their intrinsic vibrational frequencies, but its notoriously weak scattering efficiency for gases presents a major obstacle to its practical application in gas sensing and analysis. This work explores the use of high finesse (50 000) Fabry-Pérot microcavities as a means to enhance Raman scattering from gases. A recently demonstrated laser ablation method, which carves out a micromirror template on fused silica--either on a fiber tip or bulk substrates-- was implemented, characterized, and optimized to fabricate concave micromirror templates ~10 µm diameter and radius of curvature. The fabricated templates were coated with a high-reflectivity …

Deep Time Evidence For Climate Sensitivity Increase With Warming, Gary Shaffer, Matthew Huber, Roberto Rondanelli, Jens Olaf Pepke Pedersen

Department of Earth, Atmospheric, and Planetary Sciences Faculty Publications

No abstract provided.

On Spectral Properties Of Single Layer Potentials, Seyed Zoalroshd

USF Tampa Graduate Theses and Dissertations

We show that the singular numbers of single layer potentials on smooth curves asymptotically behave like O(1/n). For the curves with singularities, as long as they contain a smooth sub-arc, the resulting single layer potentials are never trace-class. We provide upper bounds for the operator and the Hilbert-Schmidt norms of single layer potentials on smooth and chord-arc curves. Regarding the injectivity of single layer potentials on planar curves, we prove that among single layer potentials on dilations of a given curve, only one yields a non-injective single layer potential. A criterion for injectivity of single layer potentials on …

Communication: Visualization And Spectroscopy Of Defects Induced By Dehydrogenation In Individual Silicon Nanocrystals, Dmitry A. Kislitsyn, Jon M. Mills, Vancho Kocevski, Sheng-Kuei Chiu, William J.I. Debenedetti, Christian F. Gervasi, Benjamen N. Taber, Ariel E. Rosenfield, Olle Eriksson, Ján Rusz, Andrea Mitchell Goforth, George V. Nazin

Chemistry Faculty Publications and Presentations

We present results of a scanning tunneling spectroscopy (STS) study of the impact of dehydrogenation on the electronic structures of hydrogen-passivated silicon nanocrystals (SiNCs) supported on the Au(111)surface. Gradual dehydrogenation is achieved by injecting high-energy electrons into individual SiNCs, which results, initially, in reduction of the electronic bandgap, and eventually produces midgap electronic states. We use theoretical calculations to show that the STS spectra of midgap states are consistent with the presence of silicon dangling bonds, which are found in different charge states. Our calculations also suggest that the observed initial reduction of the electronic bandgap is attributable to the …

Synthesis, Structural Diversity, And Redox Control Of Cyclometalated Monoruthenium Complexes, Zhong-Liang Gong, Jiang-Yang Shao, Yu-Wu Zhong

Journal of Electrochemistry

Cyclometalated ruthenium complexes have received increasing attractions recently due to their excellent redox and photophysical properties. One structural feature of these complexes is that there is a ruthenium-carbon (Ru-C) σ bond presented in the molecule. Three common methods, namely, the “late metalation”, “early metalation”, and “transmetalation” methods, for the synthesis of cyclometalated ruthenium complexes are discussed and summarized. General strategies for the design of cyclometalating ligand and cyclometalated ruthenium complexes are introduced. By using different ancillary ligands, such as pyridine, imidazole, triazole, and pyrimidine, a great number of ruthenium complexes can be prepared. The presence of the Ru-C bond significantly …

Uniform Nanoshells For Functional Materials: Constructions And Applications, Shu-Yi Duan, Wei Zhang, Jun-Yu Piao, An-Min Cao, Li-Jun Wan

Journal of Electrochemistry

As a significant protocol for materials treatment, surface modification has found broad applications in different fields including catalyst, photochemistry, and electrochemistry. Herein, we introduced the representative synthetic methodologies for the constructions of different functional materials with a focus on their core-shell structures. By taking the electrode materials in lithium ion batteries as an example, we demonstrated the importance of surface modification on the electrode materials. Different coating materials ranging from metal oxides, metal phosphates to carbon have been discussed. We also showed that an accurate control on the surface layer can be crucial for optimizing the electrochemical performances of the …

3, 4-Ethylenedioxythiophene Monomer As Safety-Enhancing Additive For Lithium Ion Batteries, Wei-Xiao Ji, Feng Wang, Jiang-Feng Qian, Yu-Liang Cao, Xin-Ping Ai, Han-Xi Yang

Journal of Electrochemistry

Safety concern is a major obstacle hindering the wide applications of large-capacity lithium ion batteries (LIBs) in electric vehicles. In this paper, a polymerizable monomer of 3, 4-ethylenedioxythiophene (EDOT) was proposed and tested as an electrolyte additive for enhancing the safety of LIBs. The electro-oxidative polymerization behaviors and influence of PEDOT additive on the thermal behavior of LiCoO₂ cathode, as well as the safety performance and electrochemical properties of LiCoO₂-based LIBs were investigated. The results from cyclic voltammetry (CV) and transmission electron microscope (TEM) characterizations indicated that the monomer additive can be electro-oxidatively polymerized to form a …

Electrochemiluminescence Immunosensor Based On Platinum Nanoparticles For The Determination Of Apolipoprotein A1, Ni Liao, Ying Zhuo, Ruo Yuan

Journal of Electrochemistry

In this paper, a novel electrochemiluminescence (ECL) immunosensor for the detection of apolipoprotein A1 was constructed based on flower-like platinum nanoparticles (PtNFs) via a one-pot chemical synthesis method. The PtNFs was used to immobilize the secondary antibody and enzyme (GOD). Then the prepared bioconjugates were introduced onto the electrode via sandwich immunoreactions. Accordingly, the ECL luminophore peroxydisulfate (S₂O₈^2-) was presented in the working buffer solution containing an appropriate amount of glucose. Through the ECL responses of S₂O₈^2- and O₂, a dramatically amplified ECL signal was obtained for the reason …

Developments Of Photo-Assisted Fuel Cells, Ling-Ling Zhang, Shao-Jun Dong

Journal of Electrochemistry

The exploitation and utilization of fossil fuels have led to serious energy crisis and environmental pollution. In this case, the development of renewable energy is an alternative to traditional energy consumption. Fuel cells (FCs) can convert chemical energy into electricity via the electrochemical reaction, which is green and environment-friendly. Photo-assisted FCs integrate photo-responsive components into FCs, leading to the dual routes of energy conversion including light energy to electricity and chemical energy to electricity, and thus, improving the energy utilization efficiency. The development of photo-assisted FCs is significant for practical application and promising to solve the coming energy crisis. In …

The Influences Of Drought And Land-Cover Conversion On Inter-Annual Variation Of Npp In The Three-North Shelterbelt Program Zone Of China Based On Modis Data, Dailiang Peng, Chaoyang Wu, Bing Zhang, Alfredo Huete, Xiaoyang Zhang, Rui Sun, Liping Lei, Wenjing Huang, Liangyun Liu, Xinjie Liu, Jun Li, Shezhou Luo, Bin Fang

GSCE Faculty Publications

Terrestrial ecosystems greatly contribute to carbon (C) emission reduction targets through photosynthetic C uptake.Net primary production (NPP) represents the amount of atmospheric C fixed by plants and accumulated as biomass. The Three-North Shelterbelt Program (TNSP) zone accounts for more than 40% of China’s landmass. This zone has been the scene of several large-scale ecological restoration efforts since the late 1990s, and has witnessed significant changes in climate and human activities.Assessing the relative roles of different causal factors on NPP variability in TNSP zone is very important for establishing reasonable local policies to realize the emission reduction targets for central government. …

Strategies For Promoting Equity In Clean Energy Deployment, Tracy Babbidge, New Haven Green Fund

Reports

No abstract provided.

Dead Trees Don’T Mean Catastrophe For California, Char Miller

Pomona Faculty Publications and Research

Nature knows what it’s doing. You’d never know that, though, from the panicked reaction to news that 66 million trees in California have died since 2005, including 26 million said to have perished just in the last few months.

Energy Consumption Prediction With Big Data: Balancing Prediction Accuracy And Computational Resources, Katarina Grolinger, Miriam Am Capretz, Luke Seewald

Electrical and Computer Engineering Publications

In recent years, advances in sensor technologies and expansion of smart meters have resulted in massive growth of energy data sets. These Big Data have created new opportunities for energy prediction, but at the same time, they impose new challenges for traditional technologies. On the other hand, new approaches for handling and processing these Big Data have emerged, such as MapReduce, Spark, Storm, and Oxdata H2O. This paper explores how findings from machine learning with Big Data can benefit energy consumption prediction. An approach based on local learning with support vector regression (SVR) is presented. Although local learning itself is …

Simultaneous Metal-Insulator And Antiferromagnetic Transitions In Orthorhombic Perovskite Iridate Sr0.94Ir0.78O2.68 Single Crystals, Hao Zheng, Jsaminka Terzic, Feng Ye, X. G. Wan, D. Wang, Jinchen Wang, Xiaoping Wang, P. Schlottmann, Shujuan Yuan, Gang Cao

Center for Advanced Materials Faculty Publications

The orthorhombic perovskite SrIrO₃ is a semimetal, an intriguing exception in iridates where the strong spin-orbit interaction coupled with electron correlations tends to impose an insulating state. We report results of our investigation of bulk single-crystal S_r0.94Ir_0.78O_2.68 or Ir-deficient, orthorhombic perovskite SrIrO₃. It retains the same crystal structure as stoichiometric SrIrO₃ but exhibits a sharp, simultaneous antiferromagnetic (AFM) and metal-insulator (MI) transition occurring in the basal-plane resistivity at 185 K. Above it, the basal-plane resistivity features an extended regime of almost linear temperature dependence up to 800 K but the strong …

Ultraviolet Emission Lines Of Si Ii In Quasars—Investigating The "Si Ii Disaster", Sibasish Laha, Francis P. Keenan, Gary J. Ferland, Catherine A. Ramsbottom, Kanti M. Aggarwal

Physics and Astronomy Faculty Publications

The observed line intensity ratios of the Si II λ1263 and λ1307 multiplets to that of Si II λ1814 in the broad-line region (BLR) of quasars are both an order of magnitude larger than the theoretical values. This was first pointed out by Baldwin et al., who termed it the "Si II disaster," and it has remained unresolved. We investigate the problem in the light of newly published atomic data for Si II. Specifically, we perform BLR calculations using several different atomic data sets within the CLOUDY modeling code under optically thick quasar cloud conditions. In addition, …

Video Data Collection For Continuous Identity Assurance, Janani Venkatesan

USF Tampa Graduate Theses and Dissertations

Frequently monitoring the identity of a person connected to a secure system is an important component in a cyber-security system. Identity Assurance (IA) mechanisms which continuously confirm and verify users’ identity after the initial authentication process ensure integrity and security. Such systems prevent unauthorized access and eliminate the need of an authorized user to present credentials repeatedly for verification. Very few cyber-security systems deploy such IA modules. These IA modules are typically based on computer vision and machine learning algorithms. These algorithms work effectively when trained with representative datasets. This thesis describes our effort at collecting a small dataset of …

Some Results Concerning Permutation Polynomials Over Finite Fields, Stephen Lappano

USF Tampa Graduate Theses and Dissertations

Let p be a prime, p a power of p and 𝔽_q the finite field with q elements. Any function φ: 𝔽_q → 𝔽_q can be unqiuely represented by a polynomial, 𝔽_φ of degree < q. If the map x ↦ F_φ(x) induces a permutation on the underlying field we say F_φ is a permutation polynomial. Permutation polynomials have applications in many diverse fields of mathematics. In this dissertation we are generally concerned with the following question: Given a polynomial f, when does the map x ↦ F( …

Blind And Visually Impaired Users Adaptation To Web Environments: A Qualitative Study, Raneem Saqr

USF Tampa Graduate Theses and Dissertations

Although much research exists on human behavior in online environments, research on users with disabilities is still rare. To draw more attention to this population, this dissertation explored browsing patterns and adaptive behaviors of people with visual disability across different online environments common in daily activities: social network, e-commerce, online information, and search engines’ websites. The main objective of this study is to propose a conceptual framework of how blind and visually impaired users browse and adapt to different web environments. We achieve this objective using a qualitative approach through three studies. In the first study, the researchers collect data …

Spatially Directional Resorcin[4]Arene Cavitand Glycoconjugates For Organic Catalysis In Aqueous Media, Ali Husain Husain

USF Tampa Graduate Theses and Dissertations

Resorcin[4]arenes and their rigid structures “cavitands” offer a unique molecular structure scaffolds suitable for attaching and orienting multi-ligands on their upper rims. Their remarkable structure properties, the relative ease of chemical modification on their either rims or through the multiple phenolic hydroxyl (-OH) groups, manipulating their cavity size and the role of spatial directionality provided by their cores, led synthetic chemist to explore their utilities in the synthesis of valuable resorcin[4]arene/cavitand assemblies with wide range of applications in many research areas such as supramolecular chemistry, host-guest chemistry, glycoconjugates, polymer chemistry, host-guest chemistry, micro-reactors in chemical catalysis and others. In particular, …

Exploring The Relationship Of Mbd1 Protein Binding Cpg Sites Of Methylated Dna, Shelby L. Scherer

Honors College Theses

Methylated DNA binding (MBD) proteins control transcriptional regulation by binding methylated DNA at CpG islands to modulate transcriptional activation and silencing of specific genes such as tumor suppressors. The goal is to explore the structure/function relationship between MBD proteins and methylated DNA recognition. By synthesizing the methylated DNA binding region of the MBD1 protein, binding studies test the peptide’s affinity and specificity for methylated DNA. Fluorescence, circular dichroism, and thermal denaturation techniques are utilized to determine the binding affinities and structures of peptides. Studies of peptide mutations can monitor the effectiveness of methylated DNA binding compared to the original peptide. …

Leveraging New Platforms To Provide Students With A Realistic Soc Design Experience, Andrew Danowitz, Antonio M. Leija

Computer Science and Software Engineering

Recently there have been a slew of digital design products released that promise to simplify the task of giving students a real-world System-on-Chip (SoC) design experience. These “programmable SoCs” from companies such as Xilinx, Cypress, and Altera combine modern multi-core ARM processors connected to an FPGA through a widely used SoC interconnect standard. This paper discusses a Real Time Embedded System Course I designed that uses the Xilinx Zynq platform to give students first-hand experience with modern System-on-Chip design methodologies and the challenges that designers face in both hardware and software bring-up for a modern IP-based design.

The first portion …

The Erskine Fire And Public-Lands Management In The American West, Char Miller

Pomona Faculty Publications and Research

The Erskine Fire is big, fast and dangerous. Its power is evident in the tragic loss of life, the incineration of an estimated 150 structures and its rapid growth — more than 36,000 acres burned in its first 30 hours.

Dango (Doings And Goings On) - Vol. 22 | Issue 6, Hannah Hamilton, Matthew Kimball, Aric Tate, Haley Stien, Vicente Rojas, Caleb Hicks, Zhaojia Xi, Joshua Daniel Martinez, Reuben Byrd, Paul Carstens, Mike Daugherity, Donald Isenhower

DANGO: Doings and Goings On: Summer Research Newsletter, Department of Engineering and Physics

Weekly newsletter from ACU Physics and Engineering

Longitudinal Success Of Calculus I Reform, Doug Bullock, Kathrine E. Johnson, Janet Callahan

Mathematics Faculty Publications and Presentations

This paper describes the second year of an ongoing project to transform calculus instruction at Boise State University. Over the past several years, Calculus I has undergone a complete overhaul that has involved a movement from a collection of independent, uncoordinated, personalized, lecture-based sections, into a single coherent multi-section course with an activelearning pedagogical approach. The overhaul also significantly impacted the course content and learning objectives. The project is now in its fifth semester and has reached a steady state where the reformed practices are normative within the subset of instructors who might be called upon to teach Calculus I. …

Demo: Wanda, Securely Introducing Mobile Devices, Timothy J. Pierson, Xiaohui Liang, Ronald Peterson, David Kotz

Dartmouth Scholarship

Nearly every setting is increasingly populated with wireless and mobile devices – whether appliances in a home, medical devices in a health clinic, sensors in an industrial setting, or devices in an office or school. There are three fundamental operations when bringing a new device into any of these settings: (1) to configure the device to join the wireless local-area network, (2) to partner the device with other nearby devices so they can work together, and (3) to configure the device so it connects to the relevant individual or organizational account in the cloud. The challenge is to accomplish all …

Projected Temperature And Precipitation Changes In Central And East Texas Over The Next 50 Years, Katharyn Cotsakis

Ursidae: The Undergraduate Research Journal at the University of Northern Colorado

No abstract provided.

Overexpression Of The Bcl11a Transcription Factor In Basal-Like Versus Luminal Breast Cancer Cells, Alexis Cororan, Matthew Deselm

Ursidae: The Undergraduate Research Journal at the University of Northern Colorado

No abstract provided.

Face-Wise Chromatic Number, Cat Myrant

Ursidae: The Undergraduate Research Journal at the University of Northern Colorado

The chromatic number is a well-studied graph invariant. This is the smallest number of colors necessary to color all the vertices such that no two vertices adjacent to the same edge are the same color. It has a myriad of applications from scheduling problems to cartography. Here we consider what happens when we color vertices with respect to faces instead of edges. That is, two vertices adjacent to the same face must not be the same color. We call this invariant the face-wise chromatic number (fwcn). We will see how to compute the fwcn for a variety of graphs and …

Defining The Spatial And Average Intensity Of The Louisville Urban Heat Island, Joshua Clark

Ursidae: The Undergraduate Research Journal at the University of Northern Colorado

The urban heat island (UHI) effect, a phenomenon where the urban area will be warmer than the rural surroundings, may adversely impact human health and energy consumption via heat waves and rolling blackouts. A quantitative assessment of the UHI in Louisville, Kentucky was conducted through climatological analysis of five observation stations over a 5-year period from 2009 –2013. Results indicate the presence of a large UHI extending beyond 40 km, with an average intensity of 4.84°C between the most rural station and the urban control. By analyzing the temperature differences between all stations based on time and meteorological conditions, it …

The Safe Bet: An Exploration Of Games Of Chance, Alex Clayton Ellis, Thomas Hicks

Ursidae: The Undergraduate Research Journal at the University of Northern Colorado

The purpose of this study is to explore motivations and behaviors related to games of chance. An online snowball sample of 70 gamers completed the 25-item questionnaire consisting of questions measuring intelligence, motivation, amenities, and motivation to learn games of chance. T-test results indicated that males were more motivated by complexity and house odds of games than females. A visual inspection of the crosstab scores of the knowledge test revealed that players who prefer table games scored higher on the knowledge test than players that prefer slot machines. Also, the data suggested that slot players prefer games that require little …