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Two-Dimensional Transient Spectroscopy Measuring Heterogeneity In Electronic And Rotational Dynamics, Haorui Wu

Theses and Dissertations

Multiple population-period transient spectroscopy (MUPPETS) is a picosecond, time resolved experiment that uses a sequence of six laser pulses. It was previously known that MUPPETS could measure heterogeneity in electronic-state decay. This dissertation presents two projects that extend MUPPETS to new processes. One process is the extension from 2-level system into 3-level system, another new process extends the kinetics from electronic decay to rotational decay. In addition, a third, ongoing project on rotational dynamics in ionic liquids will also be discussed briefly. The first project consisted of two main parts. The first part focused on the biexciton decay in semiconductor …

Study Of Homogeneous Mineral Acid Dehydration Of Monosaccharides In A Cstr, Siddharth Sharad Bhat

Dissertations - ALL

Simple sugars (Aldohexoses/pentoses), (Ketohexoses/pentose) when subjected to a dehydration reaction, produce various compounds. An example of one such compound is 5-hydroxymethyl furfural. Such chemical products may be used in subsequent processing steps (hydrolysis, aldol condensation, hydrogenation and dehydration) to produce similarly structured condensed compounds that form the basis of complex molecules used in various industries such as production of fuels, chemical reagents and fertilizers. Most studies focus on heterogeneous packed beds and batch reactors to carry out dehydration reactions. This study illustrates use of a Continuous Stirred-Tank reactor to carry out such dehydration reactions. In order to maintain the homogenous …

Human Carbonic Anhydrase Ii; Preparation, Metal-Substitution, Activity, And Inhibition, David L. Wilson

Theses and Dissertations

This report details the activities and inhibition of metal-substituted human carbonic anhydrase II (M-HCA-II). The traditional activities (hydrolysis of CO2 and para-nitrophenol acetate) in addition to new activities (oxidation of 2-aminophenol, disproportionation of H2O2, and disproportionation of superoxide) were investigated. Values reported for the relative hydrolytic activities of M-HCA-IIs are reported here for the first time, ranging from 47.5 % (plus or minus 0.6) to 86 % (plus or minus 4) for the hydrolysis of CO2 and from 0.299 % (plus or minus 0.012) to 4.72 % (plus or minus 0.015) for the hydrolysis of para-nitrophenol acetate. With respect to …

Ribosome Component Turnover Kinetics Describes A Two-Pool Kinetic Model In Dietary Restriction That Suggests Rpl10 Is Exchanged During Ribosome Lifespan, Andrew David Mathis

Theses and Dissertations

The eukaryotic ribosome is a large molecular machine consisting of ~80 ribosomal proteins and 4 rRNAs. The 40S and 60S ribosomal subunits are assembled in the nucleolus by ~200 helper proteins then shipped into the cytoplasm or to the endoplasmic reticulum where protein translation takes place. Eventually ribosomes are removed from the cytoplasm and recycled through ribophagy, however, very is little is known about ribosomal protein exchange after assembly but before ribophagy. Using kinetic turnover measurements of ribosomal proteins and rRNA in vivo we determined ribosomal protein replacement rates are diverse suggesting ribosomal components may be replaced without destruction of …

Peroxy Radical - Water Complexes: Their Role In The Atmosphere, Sambhav Rajendra Kumbhani

Theses and Dissertations

The importance of radical-water complexes in the atmosphere is explored in this dissertation. Radicals, although present in small concentrations in the atmosphere, play a significant role in creating and removing atmospheric pollution. As the atmosphere warms and consequently gets wetter, it is essential to understand the effects of water vapor on radical chemistry. This dissertation reports studies on the effects of water vapor on the kinetics of the self-reaction of β-hydroxyethyl peroxy radical (β-HEP), a prominent organic peroxy radical in the atmosphere. Both experimental and computational studies have been performed to examine the effects of water vapor on the kinetics …

Thermodynamic And Kinetic Simulation Of Transient Liquid-Phase Bonding, Brad Allen Lindner

Theses and Dissertations

ABSTRACT

THERMODYNAMIC AND KINETIC SIMULATION OF TRANSIENT LIQUID-PHASE BONDING

by

Brad Lindner

The University of Wisconsin-Milwaukee, 2015

Under the Supervision of Professor Benjamin C. Church

The use of numeric computational methods for the simulation of materials systems is becoming more prevalent and an understanding of these tools may soon be a necessity for Materials Engineers and Scientists. The applicability of numerical simulation methods to transient liquid-phase (TLP) bonding is evaluated using a type 316L/MBF-51 material system. The comparisons involve the calculation of bulk diffusivities, tracking of interface positions during dissolution, widening, and isothermal solidification stages, as well as comparison of …

Lower Extremity Neuromechanics During A Forward-Side Jump Following Functional Fatigue In Patients With Ankle Instability, Hyun Kim

Theses and Dissertations

Ankle instability (AI) and fatigue impair neuromuscular control as well as dynamic joint stability of the lower extremity. No one has comprehensively examined the effects of AI and fatigue on neuromechanics of the lower extremity during a functional activity. Deficits associated with AI and fatigue could be additive in increasing the risk for injury in patients with AI. PURPOSE: To examine the interaction of AI and fatigue on lower extremity muscle activity, kinematic, and kinetic patterns during a forward-side jump. METHODS: 25 AI (23.3 ± 1.9 yrs, 176.5 ± 10.5 cm, 70.9 ± 11.4 kg), and 25 matched control subjects …

Monitoring Dissolution Of Nonsteroidal Anti-Inflammatory Drugs Using Infrared Spectroscopy, Julianne Berger

Seton Hall University Dissertations and Theses (ETDs)

A comparison study was conducted to look at the formulation of three brands of naproxen sodium. These brands included Bayer Aleve ®, CVS All Day Pain Relief and Walgreens All Day Pain Relief. The active and inactive ingredients were the same yet the size and shape of the tablets differ among the three brands. S-naproxen was extracted from the tablets and evaluated by GC-MS to determine the purity of naproxen in the tablets. Dissolution was monitored by an IR probe for eight hours while using 0.1M phosphate buffer pH 7.4, 0.05M phosphate buffer pH 4.5 and simulated gastric fluid pH …

I. Kinetic And Computational Modeling Studies Of Dimethyldioxirane Epoxidations Ii. Adressing Misconceptions About Energy Changes In Chemical Reactions Through Hands-On Activities, Davita Mctush-Camp

Chemistry Dissertations

Kinetic studies determining the second order rate constants for the monoepoxidation of cyclic dienes, 1,3-cyclohexadiene and 1,3-cyclooctadiene, and the epoxidation of cis-/trans-2-hexenes by dimethyldioxirane (DMDO) were carried out using UV methodology. Consistent with published results, the kinetics of cis-/trans-2-hexenes by DMDO showed greater reactivity of the cis-isomer compared to that of the trans-compound. Molecular modeling studies for the epoxidation of a series of cis-/trans-alkenes, by DMDO were carried out using the DFT approach. The mechanism of epoxidation by DMDO was modeled by determining the transition state geometry and calculating …

Lignin; Decomposition Kinetics, Fractionation And Graphene Production, Darshanamala Dissanayake

Theses and Dissertations

Lignin is the most abundant natural aromatic polymer on the earth. In this work, lignin properties were studied in order to explore its use as a low cost carbon precursor for graphene production. Initial studies focused on kinetics of lignin pyrolysis using ‘Kissinger method’ and ‘ASTM E 1641’ using thermogravimetry. The values obtained for kinetic parameters varied for the two methods and activation energy increased with increase in lignin purity. Lignin was solvent fractionated, using three organic solvents to extract the high molecular weight fraction suitable for the production of highly ordered graphene nano platelets. Acetone and Methanol were successful …

A Study Of The Kinetics Of A Reaction Between Vo(Hedta)-1 And Hydrogen Peroxide, Elaina B. Campbell

Undergraduate Honors Theses

Vanadium is commonly used as an agent to make tools rust-resistant. As a transition metal, it can be used as a catalyst due to its ability to change oxidation states. VO(HEDTA)^-1, a complex of the vanadyl ion, VO²⁺ and HEDTA (N-(2-Hydroxyethyl)ethylenediamine-N,N’,N’-triacetic acid) was readily formed. This complex containing vanadium in the +4 oxidation state was reacted with hydrogen peroxide to form a vanadate complex. This vanadate complex was formed as a first step in simulating the vanadate(V)-dependent haloperoxidases in marine algae, a yet uncharacterized reaction. Electron absorption spectroscopy (UV-Vis) was used to observe the oxidation of V(IV) …

Investigating Single-Leg Landing Strategies And Movement Control Across Changes In Task Demands, Andrew D. Nordin

UNLV Theses, Dissertations, Professional Papers, and Capstones

Variability is an intrinsic characteristic of human movement, with hypothesized connections to neuromotor functioning and mechanisms of injury. The purpose of this study was to evaluate changes in movement variability among kinematic, kinetic, and electromyographic (EMG) variables following mechanical task demand manipulations during single-leg drop landings. Biomechanical outcome variables included 3 kinematic (sagittal, hip, knee, and ankle angles), 4 kinetic (sagittal hip, knee, ankle moments and vertical ground reaction force; GRFz), and 5 EMG variables (gluteus maximus, vastus medialis, biceps femoris, medial gastrocnemius, and tibialis anterior muscles). Mechanical task demands were altered using load and landing height manipulations, computed as …

Changes In Sprint Kinetics Or Kinematics Following Static Or Dynamic Stretching, Kristyne Bartel

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study was to determine the effects of static or dynamic stretching on hip kinematics and kinetics during intermittent sprinting. To achieve this aim, intermittent sprint athletes were asked to complete either a static or dynamic stretch, followed by a repeated-sprint protocol. Hip joint kinematics and performance measures were evaluated during the sprint, including changes that occurred in these variables over the course of the sprint protocol. In addition, hip flexion torque was measured with an isokinetic dynamometer. Ten male (age = 25±2.3 years, 175±3.2 cm, 76.2±2.7 kg) and female (age = 20±1 years, 166±1.3 cm, 60±1.1 …

Factors Influencing Kinetics Of Electrode Processes In Vanadium Redox Flow Batteries, Emma Hollmann

Chancellor’s Honors Program Projects

No abstract provided.

The Effects Of Imposed Foot Strike And Fatigue On Joint Stiffness And Metabolic Cost In Rearftoot Strike Runners, Daniel A. Melcher

Electronic Theses and Dissertations

Running research has focues ont he effects of acute strike pattern modifications, specifically to lower extremity joint kinetics and stiffness. Joint stiffness may be related to injury risk in runners. As 75% of runners use a RFS pattern, it is worthwhile to study these runners. The purpose of this tudy was to xamine th eeffects of imposed FFSon ankle and knee joint stiffness before and after a long run in habitual RFSrunners. Ankl eand knee joinst stiffness as well as running economy were measured pre and post fatiguing long run. Ankle joint stiffness was lower during imposed FFS. Knee joint …

Bio-Crosslinking Of Starch Films With Oxidized Sucrose, Hazal Canisag

Department of Textiles, Merchandising, and Fashion Design: Dissertations, Theses, and Student Research

In this work, corn starch films were crosslinked with a novel bio-based agent; oxidized sucrose and their strength and stability were improved. Although starch is an inexpensive, biodegradable and abundant source, industrial applications of starch films are limited due to their poor mechanical properties. Crosslinking is one of the most common methods to enhance the mechanical properties of starch films. However, most of the available crosslinkers, such as gluteraldehyde, phosphorus oxychloride, sodium trimetaphosphate, and epichlorohydrin, are either toxic, expensive or with low crosslinking efficiencies. Oxidized sucrose, which is derived by periodate cleavage, has aldehyde groups in the structure and this …

The Influence Of Long-Term Gamma-Radiation And Initially Dissolved Chemicals On Aqueous Kinetics And Interfacial Processes, Pamela A. Yakabuskie

Electronic Thesis and Dissertation Repository

This thesis presents work focusing on the long-term effect of gamma-radiation on aqueous solution kinetics. Ionizing radiation drives the decomposition of water to form both oxidizing (•OH, O₂, H₂O₂) and reducing (•e_aq⁻, •O₂⁻, •H, H₂) chemical species. Over time, these radiolysis products can react with dissolved solutes and participate in interfacial reactions. This can lead to significant changes in the eventual solution redox condition, and gas phase composition, and in certain cases result in the formation of solid species. Understanding the long-term solution kinetics for radiolysis …

Platination Kinetics: Insight Into Rna-Cisplatin Interactions As A Probe For Rna Microenvironments, Gayani Dedduwa-Mudalige

Wayne State University Dissertations

RNAs are crucial for many cellular functions. Thus, studying ligand-RNA interactions and their dynamics in response to changes in the surrounding environment is important. In spite of the well-known DNA coordination, current research also indicates cisplatin binding to RNA. Kinetic studies of rRNA platination reactions are largely unexplored. This research was conducted to achieve two objectives. First, a broad kinetic study was carried out to investigate the cisplatin-rRNA interactions. The structure, function, and ligand interactions depend on RNA microenvironments. Second, the application of platination kinetics as a tool to interrogate RNA electrostatic environments was explored.

Three model rRNA hairpins from …

Thiol-Disulfide Exchange In Human Growth Hormone, Saradha Chandrasekhar

Open Access Dissertations

The biopharmaceutical industry has been growing at a tremendous rate, with sales of $63.6 billion 2012 in the US [1]. Nevertheless, the successful development of many protein drugs has been impeded by physical and chemical instabilities arising from their inherent chemical complexity and often leading to protein aggregation. The formation of non-native disulfide bonds is a common route to covalent aggregation of therapeutic proteins and other biologics [2, 3]. Disulfide bonds participate in hydrolytic and oxidative degradation reactions that form non-native disulfide bonds and other reactive species. The mechanisms responsible for protein aggregation are poorly understood and formulations are currently …

Climate Anomalies And Primary Production In Lake Superior, Marcel L. Dijkstra

Dissertations, Master's Theses and Master's Reports - Open

This dissertation supports the modeling of primary production in Lake Superior by offering site specific kinetics and algorithms developed from lab experiments performed on the natural phytoplankton assemblage of Lake Superior. Functions, developed for temperature, light and nutrient conditions and the maximum specific rate of primary production, were incorporated in a 1D specific primary production model and confirmed to published in-situ measured rates of primary production.

An extensive data set (supporting model calibration and confirmation), with a fine spatiotemporal resolution, was developed from field measurements taken bi-weekly during the sampling seasons of 2011, 2012 and 2014; considered to be meteorologically …

The Effects Of Fatigue On Lower Extremity Kinetics And Kinematics In Subjects With Known Ankle Instability, Lindsay E. Clayton

Theses and Dissertations

The goal of this study was to evaluate biomechanical differences between healthy subjects and those with ankle instability during the gradual onset of lower extremity fatigue from a landing activity. An understanding of these differences is needed in order to prevent future injury to or further debilitation in individuals with ankle instability. A functional fatiguing activity was designed to focus fatigue on the quadriceps muscles, as those are the muscles most frequently fatigued during sport. Measures were taken throughout the progression of fatigue with a force plate and a motion tracking system and included vertical ground reaction force and lower …

Biomechanical Analysis Of Race Walking Compared To Normal Walking And Running Gait, Jaclyn D. Norberg

Theses and Dissertations--Kinesiology and Health Promotion

Human locomotion is phenomenon that is extraordinarily complex. It is evident that a complete description of locomotion involves consideration of kinematics, kinetics, and muscle activity of the extremities in all of their various movements. Race walking (RW) is a form of upright locomotion that differs from normal walking and running by its form dictated by the International Amateur Athletics Federation (IAAF). Despite the similarities to both normal walking (NW) and running (RU), RW has not been the subject of equally intensive investigations.

This study explores the comprehensive biomechanics of race walking and how it compares to NW and RU. A …

An Improved Biosolid Gasifier Model, Hannah Mclean

Electronic Theses and Dissertations

As populations increase and cities become denser, the production of waste, both sewage sludge and food biomass, increases exponentially while disposal options for these wastes are limited. Landfills have minimal space for biosolids; countries are now banning ocean disposal methods for fear of the negative environmental impacts. Agricultural application of biosolids cannot keep up with the production rates because of the accumulation of heavy metals in the soils. Gasification can convert biosolids into a renewable energy source that can reduce the amount of waste heading to the landfills and reduce our dependence on fossil fuels. A recently published chemical kinetic …

The Characterization Of Human Cytosolic Sulfotransferase 1a1: Interactions With 17Α-Ethinylestradiol, Katie Jo Glowacki

All ETDs from UAB

Human cytosolic sulfotransferases (SULTs) are a family of Phase II conjugating enzymes that facilitate the transfer of a sulfonate moiety from 3’phosphoadenosine 5’phosphosulfate (PAPS) to hydroxyl or amine groups of acceptor substrates. SULT1A1, located in many tissues throughout the human body including the liver, is important in the metabolism of many endogenous, exogenous, xenobiotic, and drug compounds. The majority of substrates for SULT1A1 are small neutral phenols including 1-naphthol and acetaminophen; however, SULT1A1 sulfates larger compounds including 17β-estradiol (E2) and raloxifene. SULT1A1 conjugates E2 with a Km of 2.3 µM and the structure of E2 is almost identical to the …

Phase Transitions Under Nanoconfining Conditions, Reza Farasat

All ETDs from UAB

The objective of this dissertation was to study the effects of nanoconfinement on the thermodynamic and kinetic parameters of phase transitions in selected compounds. The compounds were loaded into silica gel nanopores and filled them partially. A model was developed for estimating the fullness of the nanopores as well as the height of the compound layer deposited on the pore walls. A study of the phase transition in NH4Cl confined to the native silica gel nanopores revealed that the heat of transition increases with the increasing the layer height. Also the transition temperature measured on heating and cooling respectively increases …

Examination Of The Dynamic Assembly Equilibrium For E. Coli Clpb, Jiabei Lin

All ETDs from UAB

As a member of the Clp/Hsp 100 chaperone family, Escherichia coli ClpB is able to disaggregate denatured proteins with assistance of DnaKJE co-chaperones to help cell survive under stress. However, the working mechanism of ClpB disaggregation activity remains unclear. The active structure of ClpB is shown to be a hexameric ring and ATP binding and hydrolysis are required for ClpB to perform its chaperone activity. Thus, studying the energetics and kinetics of the ATP linked ClpB assembly equilibrium is essential for the quantitative examination of ClpB - protein substrate interaction to fully reveal its disaggregation mechanism. ATPgS (a slowly hydrolysable …

Interfacial Engineering Of Biomass Hydrolysis By Cellulase Enzymes And Mechanistic Modeling Of Hydrolysis Of Cellulose Substrates, Ravinder Kumar Garlapalli

Theses and Dissertations--Chemical and Materials Engineering

Lignocellulosic biomass is a sustainable and renewable energy resource that can be converted to fuels and other commodity chemicals, but this conversion is currently limited by its recalcitrance to enzymatic degradation. Because of this recalcitrance, the major challenges in the commercialization of enzymatic hydrolysis processes are the relatively low hydrolysis rates, limited cellulose conversion under some conditions, and high cost of enzymes.

Enzymatic hydrolysis is influenced by the structure of the biomass after pretreatment and the mode of enzyme action, but has also been shown to be enhanced by surfactant additives. The objective of this work was to elucidate the …

Containment Materials For Thin-Strip Casting Of Steel, Abhishek Kumar

Doctoral Dissertations

"The focus of this research was to investigate the corrosion behavior of BN-based and ZrO₂-C refractories by molten steel. These refractories are used as side-dam and core-nozzle in the thin-strip casting of steel. The improvement and development of these refractory components will increase the process efficiency by prolonging the refractory service life.

The first part of this study focused on interaction of BN-ZrO₂-SiC side-dams with steel-inclusion system in a laboratory setup under argon gas environment. It was observed that corrosion of this ceramic was severe in contact with steel compared to slag/inclusion.

The second part of …