Physical Sciences and Mathematics Commons^™

Guanidinium Compounds, Stephen Dimagno, Bao Hu

Chemistry Department: Faculty Publications

The present application provides , inter alia , chemical com pounds useful as synthesis intermediates , said compounds comprising one or more guanidinium moieties and a hyper valent iodine atom . Methods for making these compounds are also provided.

An Evaluation Of Modified Bed Load Sediment Transport Equations For Enhanced Sediment Transport Quantification In Steep Mountain Streams – Case Study Little Fountain Creek, Colorado Springs, Co., James Emerson Smith Iv

LSU Master's Theses

In mountainous regions, extreme floods occur every year, placing societies and infrastructures at risk. Communities rely on local, state, and federal agencies to emplace flood structures, perform flood risk assessments, and simulate catastrophic events. While, our ability to quantify and predict the movement of sediment in streams with low gradients is well developed (Bathurst, 1987), our ability to quantify and predict the movement of sediment along steep mountain streams (SMS) has not been developed to a similar degree (Yager, 2012; Schneider, 2016). To most effectively manage mountainous watersheds and understand the risk associated with flood events, scientists must better understand …

Target Localization And Tracking By Fusing Doppler Differentials From Cellular Emanations With A Multi-Spectral Video Tracker, Casey D. Demars, Michael Roggemann, Adam Webb, Timothy C. Havens

Michigan Tech Publications

We present an algorithm for fusing data from a constellation of RF sensors detecting cellular emanations with the output of a multi-spectral video tracker to localize and track a target with a specific cell phone. The RF sensors measure the Doppler shift caused by the moving cellular emanation and then Doppler differentials between all sensor pairs are calculated. The multi-spectral video tracker uses a Gaussian mixture model to detect foreground targets and SIFT features to track targets through the video sequence. The data is fused by associating the Doppler differential from the RF sensors with the theoretical Doppler differential computed …

Non-Abelian Quasiholes In Lattice Moore-Read States And Parent Hamiltonians, Sourav Manna, Julia Wildeboer, Germán Sierra, Anne E. B. Nielsen

Physics and Astronomy Faculty Publications

This work concerns Ising quasiholes in Moore-Read type lattice wave functions derived from conformal field theory. We commence with constructing Moore-Read type lattice states and then add quasiholes to them. By use of Metropolis Monte Carlo simulations, we analyze the features of the quasiholes, such as their size, shape, charge, and braiding properties. The braiding properties, which turn out to be the same as in the continuum Moore-Read state, demonstrate the topological attributes of the Moore-Read lattice states in a direct way. We also derive parent Hamiltonians for which the states with quasiholes included are ground states. One advantage of …

Game-Theoretic And Machine-Learning Techniques For Cyber-Physical Security And Resilience In Smart Grid, Longfei Wei

FIU Electronic Theses and Dissertations

The smart grid is the next-generation electrical infrastructure utilizing Information and Communication Technologies (ICTs), whose architecture is evolving from a utility-centric structure to a distributed Cyber-Physical System (CPS) integrated with a large-scale of renewable energy resources. However, meeting reliability objectives in the smart grid becomes increasingly challenging owing to the high penetration of renewable resources and changing weather conditions. Moreover, the cyber-physical attack targeted at the smart grid has become a major threat because millions of electronic devices interconnected via communication networks expose unprecedented vulnerabilities, thereby increasing the potential attack surface. This dissertation is aimed at developing novel game-theoretic and …

Elemental Analysis Of Adhesive Tapes By Laser-Based Methods, Claudia Martinez Lopez

FIU Electronic Theses and Dissertations

Adhesive tapes are a common type of evidence involved in violent crimes and national security threats. This research evaluated the utility of LA-ICP-MS and LIBS for the characterization of the trace elemental signature in adhesive tapes for forensic comparisons. LA-ICP-MS and LIBS methods were developed, for the first time, for the qualitative and quantitative analysis of adhesive tapes.

The backings of 90 black electrical tapes, previously characterized by conventional techniques (physical examination, IR, Py-GC-MS, and SEM-EDS), were analyzed by LA-ICP-MS to evaluate the ability of the technique to discriminate samples originating from different sources and to associate pieces of tapes …

Synthesis And Characterization Of A Series Of Vanadium ( Iv ) Complexes With The Kläui Ligand, Xiao Wu

Theses and Dissertations

Cyclopentadienyltris (dibutyl phosphito-P) cobaltate, {(C5H5)Co[(OR)2PO]3}– (R=Bu), is a tripodal ligand and also called Kläui ligand (R=Bu). The synthesis and characterization of several vanadium(III) and vanadium(IV) complexes containing Kläui ligand (R=Bu) as the catalytic models to catalyst the oxidation reaction of 3,5-di-tert-butylcatechol (3,5-DTBC) to 3,5-di-tert-butyl-o-benzoquinone (3,5-DTBQ) are detailed here. Chapter II details the synthesis of the supersandwiches and Kläui ligand (R=Bu). Chapter III details the synthesis of vanadium monomeric complexes containing Kläui ligand (R=Bu). Chapter IV details the vanadium dimeric bridging complexes synthesized by different vanadium monomers from Chapter III. Chapter V details the catalytic activities of these vanadium complexes.

Heme Dissociation From Myoglobin In The Presence Of The Zwitterionic Detergent N,N-Dimethyl-N-Dodecylglycine Betaine: Effects Of Ionic Liquids, Eric M. Kohn, Joshua Y. Lee, Anthony Calabro, Timothy Vaden, Gregory A. Caputo

College of Science & Mathematics Departmental Research

We have investigated myoglobin protein denaturation using the zwitterionic detergent Empigen BB (EBB, N,N-Dimethyl-N-dodecylglycine betaine). A combination of absorbance, fluorescence, and circular dichroism spectroscopic measurements elucidated the protein denaturation and heme dissociation from myoglobin. The results indicated that Empigen BB was not able to fully denature the myoglobin structure, but apparently can induce the dissociation of the heme group from the protein. This provides a way to estimate the heme binding free energy, ΔGdissociation. As ionic liquids (ILs) have been shown to perturb the myoglobin protein, we have investigated the effects of the ILs 1-butyl-3-methylimidazolium chloride (BMICl), 1-ethyl-3-methylimidazolium acetate (EMIAc), …

Testing Velocity-Dependent Cpt-Violating Gravitational Forces With Radio Pulsars, Lijing Shao, Quentin G. Bailey

Publications

In the spirit of effective field theory, the standard-model extension (SME) provides a comprehensive framework to systematically probe the possibility of Lorentz/CPT violation. In the pure gravity sector, operators with mass dimension larger than 4, while in general being advantageous to short-range experiments, are hard to investigate with systems of astronomical size. However, there is exception if the leading-order effects are CPT-violating and velocity-dependent. Here we study the lowest-order operators in the pure gravity sector that violate the CPT symmetry with carefully chosen relativistic binary pulsar systems. Applying the existing analytical results to the dynamics of a binary orbit, we …

Entry Of A Sphere Into A Water-Surfactant Mixture And The Effect Of A Bubble Layer, Nathan B. Spiers, Mohammad M. Mansoor, Randy Craig Hurd, Saberul I. Sharker, W. G. Robinson, B. J. Williams, Tadd T. Truscott

Mechanical and Aerospace Engineering Faculty Publications

A rigid sphere entering a liquid bath does not always produce an entrained air cavity. Previous experimental work shows that cavity formation, or the lack thereof, is governed by fluid properties, wetting properties of the sphere, and impact velocity. In this study, wetting steel spheres are dropped into a water-surfactant mixture with and without passing through a bubble layer first. Surprisingly, in the case of a water-surfactant mixture without a bubble layer, the critical velocity for cavity formation becomes radius dependent. This occurs due to dynamic surface tension effects, with the local surface tension in the splash increasing during surface …

An Investigation Of Habitat Suitability Factors And Their Interactions For Predicting Gopher Tortoise Habitat, Abigail V. Lavallin

USF Tampa Graduate Theses and Dissertations

This thesis evaluates the interaction between four habitat factors vital to the gopher tortoise in Florida. Federally and state listed as threatened throughout its entire range, the gopher tortoise is vital to protect, not only for itself individually but its burrows provide an essential habitat to over 300 species making it a key stone species within its environment. Historic habitat modeling methods are reviewed for the gopher tortoise to highlight the gap on this topic. This research expanded on the methods utilized by Baskaran et al. (2006) evaluating the soil, landcover, percentage of canopy cover and the depth to water …

Smartphone-Based Prenatal Education For Parents With Preterm Birth Risk Factors, U. Olivia Kim, K. Barnekow, Sheikh Iqbal Ahamed, S. Dreier, C. Jones, M. Taylor, Md Kamrul Hasan, M. A. Basir

Mathematics, Statistics and Computer Science Faculty Research and Publications

Objective

To develop an educational mobile application (app) for expectant parents diagnosed with risk factors for premature birth.

Methods

Parent and medical advisory panels delineated the vision for the app. The app helps prepare for preterm birth. For pilot testing, obstetricians offered the app between 18–22 weeks gestational age to English speaking parents with risk factors for preterm birth. After 4 weeks of use, each participant completed a questionnaire. The software tracked topics accessed and duration of use.

Results

For pilot testing, 31 participants were recruited and 28 completed the questionnaire. After app utilization, participants reported heightened awareness of preterm …

Analysis Of Fluvial Scroll Bar Development With Surface Wave Inversion: False River, Louisiana, Blake Odom

LSU Master's Theses

The development of ridge-and-swale scroll bar topography of meandering river point bars is not well understood. We hypothesize that scroll bars formed during lateral accretion by the landward migration of transverse bars. To explore this, we relate the scroll bar topography to the internal sedimentary structure. We acquire, invert, and interpolate three pseudo-2D shear wave velocity profiles in two regions of the False River point bar, a Mississippi river oxbow lake in Pointe Coupee Parish Louisiana. Prior studies provide electrical conductivity well logs and cores as well as SH seismic reflection images along the same seismic surveys. LiDAR elevation data …

A Survey Of Software Metric Use In Research Software Development, Nasir U. Eisty, George K. Thiruvathukal, Jeffrey C. Carver

Computer Science: Faculty Publications and Other Works

Background: Breakthroughs in research increasingly depend on complex software libraries, tools, and applications aimed at supporting specific science, engineering, business, or humanities disciplines. The complexity and criticality of this software motivate the need for ensuring quality and reliability. Software metrics are a key tool for assessing, measuring, and understanding software quality and reliability. Aims: The goal of this work is to better understand how research software developers use traditional software engineering concepts, like metrics, to support and evaluate both the software and the software development process. One key aspect of this goal is to identify how the set of metrics …

Morphodynamics Of Shell Key And Mullet Key Barrier Islands: Their Origin And Development, Zachary J. Westfall

USF Tampa Graduate Theses and Dissertations

Shell Key and Mullet Key are two sandy barrier islands on the West Central Florida coast near the mouth of Tampa Bay. These islands are part of an interconnected barrier-inlet system that includes Pass-a-Grille (PAG) and Bunces Pass. Shell Key is a relatively new island about 40-years of age that formed in between the two inlets of Bunces Pass and PAG. Mullet Key is an island to the south of Shell Key situated between Bunces Pass and the main Tampa Bay channel that has demonstrated large scale upward shoaling events. Using numerical modeling, the wave and tidal conditions at the …

Signature Of Obliquity And Eccentricity In Soil Chronosequences, Christopher Shepard, Jon D. Pelletier, Marcel G. Schaap, Craig Rasmussen

Plant and Soil Sciences Faculty Publications

Periodic shifts in Earth's orbit alter incoming solar radiation and drive Quaternary climate cycles. However, unambiguous detection of these orbitally driven climatic changes in records of terrestrial sedimentation and pedogenesis remains poorly defined, limiting our understanding of climate change‐landscape feedbacks, impairing our interpretation of terrestrial paleoclimate proxies, and limiting linkages among pedogenesis, sedimentation, and paleoclimatic change. Using a meta‐analysis, we show that Quaternary soil ages preserved in the modern record have periodicities of 41 and 98 kyr, consistent with orbital cycles. Further, soil ages predominantly date to periods of low rates of climatic change following rapid climate shifts associated with …

Lake Surface Water Temperature Change Over The Tibetan Plateau From 2001 To 2015a Sensitive Indicator Of The Warming Climate, W. Wan, L. Zhao, H. Xie, B. Liu, H. Li, Ying Cui, Yan Ma

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The Tibetan Plateau (TP) plays a significant role in the Earth's climate system. This letter examines the nighttime lake surface water temperature (LSWT) of 374 lakes (≥10 km 2 each) over the TP for the past 15 years (2001–2015). An overall warming trend (0.037 °C/year) is found and it is consistent with the warming air temperature (0.036 °C/year) over the TP, with the vast majority of the lakes (70%, with 28% of which are significant) showing warming (0.076 °C/year) and the rest (30%, with 37% of which are significant) showing cooling (−0.053 °C/year). This astonishing contrast was controlled by different …

Recent Progress In Organic Redox Flow Batteries, Li-Xing Xia, Hao Liu, Lin Liu, Zhan-Ao Tan

Journal of Electrochemistry

Redox flow batteries (RFBs) are promising candidate for balancing instability of grids caused by integration of intermittent renewable energies such as solar energy and wind energy. Along with wide deployments in solar energy and wind energy due to abundance and declining installation cost, it can be predicted that RFBs will enter a period of rapid development. Basically,RFBs are electrochemical energy storage devices that decouple energy and power of the system by storing liquid electrolyte in tanks outside battery system itself. Such a unique framework makes RFBs flexible and fulfills the various demands of grids. During battery operation, redox-active species are …

Recent Advances In Continuous Models Of Electrochemical Supercapacitors, Hao-Tian Lu, Jing-Hong Zhou, Guang-Hua Ye, Xing-Gui Zhou

Journal of Electrochemistry

Electrochemical capacitors (supercapacitors) have been developed as a new type of energy storage device with high energy and power densities, which have the advantages of both fast charging-discharging as traditional capacitors and high energy density as batteries. Notable improvements in their electrochemical performance have been achieved in recent years owing to the recent advances in understanding of charge storage mechanisms and the development of advanced nanostructured materials. Recently, modeling and simulation of these supercapacitors has been applied as a useful approach to better understand the working mechanisms of the supercapacitors by describing the concentrations and electric fields inside the capacitors. …

Recent Process In Transition-Metal-Oxide Based Catalysts For Oxygen Reduction Reaction, Yao Wang, Zi-Dong Wei

Journal of Electrochemistry

Transition metal oxides (TMOs) based catalysts have become the most promising catalysts to be employed in anion exchange membrane fuel cell for the sluggish oxygen reduction reaction (ORR). However, their ORR activity is still far from that of the Pt-based catalysts. Therefore, it is important to develop high performance TMO based catalysts. Electrical conductivity and intrinsic activity have been regarded as the two keys to affect the ORR activity of the TMOs based catalysts. In this review, we focused on the recent progresses in the fundamental viewpoints on the electrical conductivity and intrinsic activity of the TMOs based ORR catalysts. …

Two Films On Climate Change [Poster], University Of Northern Iowa. Center For Holocaust And Genocide Education.

Center for Holocaust and Genocide Education Documents

A poster announcing the showing of two films on climate change: "Age of consequences" and "Climate refugees".

Recent Advances In Non-Noble Metal Nanomaterials For Oxygen Evolution Electrocatalysis, Dan-Dan Zhao, Nan Zhang, Ling-Zheng Bu, Qi Shao, Xiao-Qing Huang

Journal of Electrochemistry

Hydrogen is a kind of renewable energies with the merits of environmentally friendly, abundance and high weight energy density, which can replace the fossil energy. The electrolysis of water is regarded as the most effective way to generate hydrogen. Owing to the sluggish kinetics and large overpotential of the anode oxygen evolution reaction (OER), the efficiency of the cathode hydrogen evolution reaction is greatly limited. Therefore, it is highly desirable to explore efficient, stable and low cost electrocatalysts to reduce the overpotential of OER and improve the efficiency of hydrogen evolution. Based on the natural characteristics of non-noble metal catalysts …

An Investigation On The Structure Of Au(111)/Imidazolium-Based Ionic Liquid Interface: Effect Of Alkyl Side Chain Length, Li Chen, Shuai Liu, Mian-Gang Li, Jian-Jia Su, Jia-Wei Yan, Bing-Wei Mao

Journal of Electrochemistry

In this work, we comparatively investigated the interfacial structures at Au(111) electrode surfaces in two ionic liquids (ILs) with different alkyl chain lengths by combining AFM force curve technique and electrochemical methods. The number and stability of the layering structures, and their potential-dependency were analyzed. The experimental results indicated that the tendencies of force-potential curves in the two ILs behave the same way. At potentials close to PZC, the ions arrange loosely, which lowers the stability of the layering structure. As the potential shifting away from PZC, more ions attach to electrode surface, which increases the stability of layering structure, …

Preface For The Special Issue Of The Award Winners, Shigang Sun

Journal of Electrochemistry

Year 2018 marks the 30th anniversary of the foundation of the Chinese Society of Electrochemistry. The past 30 years have witnessed enormous achievements of the science and technology in electrochemistry in China. The international academic communications become more and more frequent while the research quality ranks in the worldwide forefront, which make China plays more and more important roles in the international community of electrochemistry. With the stern support of domestic researchers and international colleagues, the Chinese professional academic journal，Journal of electrochemistry, has kept growing up and becoming one of the top journals in the science and technology of China. …

The New Application Of Battery-Electrode Reaction: Decoupled Hydrogen Production In Water Electrolysis, Yuan-Yuan Ma, Zhao-Wei Guo, Yong-Gang Wang, Yong-Yao Xia

Journal of Electrochemistry

Hydrogen has been considered as a promising alternative to unsustainable fossil fuels because of its high calorific value, clean and abundant resources. Water electrolysis combined with renewable energy is regarded as the best way for hydrogen production, which will become the foundation of future hydrogen economy. For the past few years, many efforts have been employed to develop the cheap and high-performance catalyst for hydrogen evolution reaction and oxygen evolution reaction. However,the coupled hydrogen and oxygen evolution and the use of the expensive membrane have greatly restricted the flexibility of the conventional water electrolysis, and hindered the utilization of renewable …

Design Strategies Toward Highly Active Electrocatalysts For Oxygen Evolution Reaction, Tang Tang, Wen-Jie Jiang, Shuai Niu, Jin-Song Hu

Journal of Electrochemistry

Electrocatalytic water splitting is pivotal for efficient and economical production of hydrogen and oxygen gasses. However, the efficiency of the whole device is largely limited by the oxygen evolution reaction (OER) at the anode due to its sluggish kinetics. Thus, it is imperative to develop inexpensive, highly active OER catalysts to lower the reaction barriers. By examining the underlying critical factors for OER performance, this review outlines general principles for designing efficient nanosized OER catalysts, including (1) enhancing the intrinsic activity of active site by electronic modulation, crystallinity modulation, phase control, defect engineering and spin state engineering; (2) designing appropriate …

Effects Of Sulfur-Containing Additive On Low Temperature Performance Of Graphite Anode, Ze-Li Wu, Ye-Zhen Zheng, Zhong-Ru Zhang, Yong Yang

Journal of Electrochemistry

The low temperature performance of lithium ion battery mainly depends on the graphite anode, and one of the research focuses is to improve the low temperature performance of the anode by additives. In this paper, the effects of different sulfur-containing functional groups such as DTD (ethylene sulfate), 1,3-PS (1,3-propane sultone) and ES (ethylene sulfite) on low temperature performances of artificial graphite materials were systematically studied. The results in density functional theory (DFT) calculations, cyclic voltammetry (CV), scanning electron microscopy (SEM) and charge-discharge measurement clearly demonstrated that all three sulfur-containing additives could participate in formation of films on the surface of …

Electrochemical Deposition Of Cr From Cr(Iii)-Based [Bmim]Hso4 And Naoac Electrolyte, De-Ying Liu, Wei Luo, Wen-Juan Zhang, Shuo-Zhen Hu, Heng Xu, Xin-Sheng Zhang

Journal of Electrochemistry

Using trivalent chromium ions (Cr(III)) as the chromium source for chromium electrodeposition has attracted much attention since it can reduce the toxicity of the whole process. Even though the chromium deposition in Cr(III)-based ionic liquid bath can avoid the most hydrogen evolution problem, CrCl₃·6H₂O is widely used as the Cr(III) precursor, which still contains water and has the stable octahedral structure. As a result, it is difficult to deposit Cr and there is still hydrogen evolution reaction (HER). Moreover, the hydroxyl ions (OH^-) produced during HER react with Cr³⁺ to form Cr(OH)_{3 …}

Electrodeposition Of Cobalt From Eutectic-Based Ionic Liquid, Rostom Ali M., Sankar Saha S, Ziaur Rahman Md

Journal of Electrochemistry

The electrodeposition of cobalt from a solution containing cobalt chloride in either a urea-choline chloride based or an ethylene glycol (EG)-choline chloride based ionic liquid has been carried out onto copper and steel cathodes by constant current and constant potential methods at different temperatures. The influences of various experimental conditions on electrodeposition and morphology of the deposited layers have been investigated by scanning electron microscopy (SEM) and X-ray diffraction (XRD)technique. It has been shown that the smooth, shiny with good adherence and bright metallic coloured cobalt coatings were obtained from both urea and EG based ionic liquids at the applied …

Preparation Of Nanoprobes And Their Possible Applications In Nanoscale Scanning Electrochemical Microscopy For Studying Electrocatalytic Oxygen And Hydrogen Reactions, Xing-Xing Chen

Journal of Electrochemistry

Scanning electrochemical microscopy (SECM) is a type of scanning probe microscopy, which can not only provide the topographical information, but also offer the electrochemical properties of different samples. The interrelationship of physical and electrochemical properties of a sample can be searched at a high-resolution scale due to the introduction of ultramicroelectrode (UME). With the continuous development of modern nanotechnology, the SECM probe has been improved with drastically decreasing its size down to nanometer. Meanwhile, to evaluate and understand the electrochemical performance of various electrocatalysts for both oxygen and hydrogen reactions with high-efficiency is highly demanded in the research area of …