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Kinetics And Activation Energy Parameters For Hydrolysis Of Acetic Anhydride In A Water-Acetone Cosolvent System, Samson Olowoyo 2018 East Tennessee State University

Kinetics And Activation Energy Parameters For Hydrolysis Of Acetic Anhydride In A Water-Acetone Cosolvent System, Samson Olowoyo

Electronic Theses and Dissertations

The hydrolysis of acetic anhydride is a widely-studied liquid phase reaction studied since 1906. Different approaches have been used to study the kinetics of this reaction. Approaches used by researchers have involved the use of sophisticated experimental set-ups. In this work, the pH technique has been adopted which involves the use of a pH meter to monitor the hydrolysis reaction. Analysis of the hydrolysis reaction has been performed for water/acetone cosolvent systems over a range of temperatures and mole fractions. Eyring analysis was performed under isomole fraction conditions and activation enthalpy, entropy, and Gibbs free energy for hydrolysis of ...


Eating Crickets? Nutrient Mineral Content Of Two Cricket Species And Chapul Cricket Protein Bars Using Mp-Aes, Nathan Hopkins 2018 Lynchburg College

Eating Crickets? Nutrient Mineral Content Of Two Cricket Species And Chapul Cricket Protein Bars Using Mp-Aes, Nathan Hopkins

Student Scholar Showcase

Global agriculture is beset by numerous challenges which must be surmounted to feed a developing world, from combating climate change to the cultivation of sustainable food products. This, in addition to protein and nutrient deficiencies in the developing world, makes considering alternative protein sources, such as a crickets, an attractive option. Crickets use a fraction of the land and water that protein sources like beef cattle do, and can be cultivated in urban environments in stacked boxes. This research investigation aims to quantify the nutrient mineral content (Iron, Sodium, Potassium, Calcium, and Magnesium) of two cricket species (Acheta domesticus & Gryllodes ...


Electrochemical And Corrosion Examination Of Copper Under Deep Geologic Conditions For The Application Of Nuclear Waste Containers, Taylor L. Martino 2018 The University of Western Ontario

Electrochemical And Corrosion Examination Of Copper Under Deep Geologic Conditions For The Application Of Nuclear Waste Containers, Taylor L. Martino

Electronic Thesis and Dissertation Repository

Copper is the selected material for the fabrication of nuclear fuel waste containers in Sweden, Finland and Canada due to its corrosion resistance in the anoxic aqueous environments, anticipated in deep geological repositories. A potential oxidant for copper is bisulphide produced either by the dissolution of minerals or by sulphate-reducing bacteria. The primary goals of this thesis were to determine the mechanism of corrosion of copper in bisulphide environments and to investigate the chemistry of the bentonite porewater that will ultimately be in contact with the copper container.

The mechanism of sulphide film growth and the details of copper corrosion ...


Monitoring The Stimulated Uncapping Process Of Gold-Capped Mesoporous Silica Nanoparticles, Ashley E. Augspurger, Xiaoxing Sun, Brian G. Trewyn, Ning Fang, Anthony S. Stender 2018 Iowa State University and Ames Laboratory

Monitoring The Stimulated Uncapping Process Of Gold-Capped Mesoporous Silica Nanoparticles, Ashley E. Augspurger, Xiaoxing Sun, Brian G. Trewyn, Ning Fang, Anthony S. Stender

Ames Laboratory Accepted Manuscripts

To establish a new method for tracking the interaction of nanoparticles with chemical cleaving agents, we exploited the optical effects caused by attaching 5–10 nm gold nanoparticles with molecular linkers to large mesoporous silica nanoparticles (MSN). At low levels of gold loading onto MSN, the optical spectra resemble colloidal suspensions of gold. As the gold is removed, by cleaving agents, the MSN revert to the optical spectra typical of bare silica. Time-lapse images of gold-capped MSN stationed in microchannels reveal that the rate of gold release is dependent on the concentration of the cleaving agent. The uncapping process was ...


A High Throughput Approach For The Generation Of Orthogonally Interacting Protein Pairs, Justin Lawrie, Xi Song, Wei Niu, Jiantao Guo 2018 University of Nebraska-Lincoln

A High Throughput Approach For The Generation Of Orthogonally Interacting Protein Pairs, Justin Lawrie, Xi Song, Wei Niu, Jiantao Guo

Faculty Publications -- Chemistry Department

In contrast to the nearly error-free self-assembly of protein architectures in nature, artificial assembly of protein complexes with pre-defined structure and function in vitro is still challenging. To mimic nature’s strategy to construct pre-defined three-dimensional protein architectures, highly specific proteinprotein interacting pairs are needed. Here we report an effort to create an orthogonally interacting protein pair from its parental pair using a bacteria-based in vivo directed evolution strategy. This high throughput approach features a combination of a negative and a positive selection. The newly developed negative selection from this work was used to remove any protein mutants that retain ...


Analysis Of Veterinary Drug Residues In Imported And Domestic Crawfish Using Liquid Chromatography—Mass Spectrometry, Emily Kate Wall 2018 Louisiana State University and Agricultural and Mechanical College

Analysis Of Veterinary Drug Residues In Imported And Domestic Crawfish Using Liquid Chromatography—Mass Spectrometry, Emily Kate Wall

LSU Master's Theses

Aquaculture production has greatly increased over the past few decades, and will continue to grow as the world fisheries become overfished and demand for seafood increases. With increased production comes more intense cultivation methods and heavy use of formulated feeds that may contain veterinary drug residues. Currently no antibiotics are allowed in the U.S. for crawfish aquaculture; yet, detectable levels of various antibiotics have been found in imported seafood samples.The FDA is responsible for testing aquaculture products entering the United States, but only has the capabilities to test a minimal amount of those imports. Additionally, for crawfish there ...


Abnormal Phase Transition Between Two-Dimensional High-Density Liquid Crystal And Low-Density Crystalline Solid Phases, Wenbin Li, Longjuan Kong, Baojie Feng, Huixia Fu, Hui Li, Xiao Cheng Zeng, Kehui Wu, Lan Chen 2018 University of Chinese Academy of Sciences

Abnormal Phase Transition Between Two-Dimensional High-Density Liquid Crystal And Low-Density Crystalline Solid Phases, Wenbin Li, Longjuan Kong, Baojie Feng, Huixia Fu, Hui Li, Xiao Cheng Zeng, Kehui Wu, Lan Chen

Xiao Cheng Zeng Publications

Some two-dimensional liquid systems are theoretically predicted to have an anomalous phase transition due to unique intermolecular interactions, for example the first-order transition between two-dimensional high-density water and low-density amorphous ice. However, it has never been experimentally observed, to the best of our knowledge. Here we report an entropy-driven phase transition between a high-density liquid crystal and low-density crystalline solid, directly observed by scanning tunneling microscope in carbon monoxide adsorbed on Cu(111). Combined with first principle calculations, we find that repulsive dipole–dipole interactions between carbon monoxide molecules lead to unconventional thermodynamics. This finding of unconventional thermodynamics in two-dimensional ...


On The Hyperbolicity Of The Two-Fluid Model For Gas–Liquid Bubbly Flows, Nithin Panicker, Alberto Passalacqua, Rodney O. Fox 2018 Iowa State University

On The Hyperbolicity Of The Two-Fluid Model For Gas–Liquid Bubbly Flows, Nithin Panicker, Alberto Passalacqua, Rodney O. Fox

Chemical and Biological Engineering Publications

The hyperbolicity condition of the system of partial differential equations (PDEs) of the incompressible two-fluid model, applied to gas–liquid flows, is investigated. It is shown that the addition of a dispersion term, which depends on the drag coefficient and the gradient of the gas volume fraction, ensures the hyperbolicity of the PDEs, and prevents the nonphysical onset of instabilities in the predicted multiphase flows upon grid refinement. A constraint to be satisfied by the coefficient of the dispersion term to ensure hyperbolicity is obtained. The effect of the dispersion term on the numerical solution and on its grid convergence ...


Crystallographic,Vibrational Modes And Optical Properties Data Of Α-Dipabcrystal, Ahmad Alsaad, Chris M. Marin, Nabil Alaqtash, Hsien-Wen Chao, Tsun-Hsu Chang, Chin Li Cheung, A. Ahmad, I. A. Qattan, Renat F. Sabirianov 2018 Jordan University of Science and Technology

Crystallographic,Vibrational Modes And Optical Properties Data Of Α-Dipabcrystal, Ahmad Alsaad, Chris M. Marin, Nabil Alaqtash, Hsien-Wen Chao, Tsun-Hsu Chang, Chin Li Cheung, A. Ahmad, I. A. Qattan, Renat F. Sabirianov

Faculty Publications -- Chemistry Department

The Crystallographic data of the α-DIPAB sample was measured using powder X-ray diffraction (PXRD). The crystal structure was also optimized using density functional based method. The calculations were performed both including vander Waals (vdW) interactions and excluding them to quantify the effects of vdW interaction on the crystal formation. The vibrational modes of DIPAB crystal corresponding to the Bromine deficient samples are calculated and presented. These show the origin of drastic change in dielectric response in Br deficient samples as compared to the ideal stoichiometric DIPAB crystal (Alsaad et al. 2018) [4]. Optical properties of an ideal α-DIPAB were calculated ...


Relationships Among Vitamin D Deficiency, Metabolic Syndrome, Smoking Behavior, And Physical Activity, Ethan Pham 2018 Walden University

Relationships Among Vitamin D Deficiency, Metabolic Syndrome, Smoking Behavior, And Physical Activity, Ethan Pham

Walden Dissertations and Doctoral Studies

Aging increases the risk of both vitamin D deficiency and metabolic syndrome. Vitamin D deficiency and metabolic syndrome may be related, although there are mixed findings. Furthermore, literature suggests other factors such as physical fitness activity and smoking behavior are associated with Vitamin D deficiency and the development of metabolic syndrome. A number of studies have documented associations between Vitamin D levels and physical fitness activities, while other studies found correlations between Vitamin D levels, metabolic syndrome, and smoking behavior. However, no previous study has examined the links between physical fitness activity, smoking behavior, Vitamin D levels, and the risks ...


Assessment Of Catalytic Function Of Gold Nanorod-Bound Tempo Under Nir Irradiation, Kristi L. St. Clair 2018 Georgia Southern University

Assessment Of Catalytic Function Of Gold Nanorod-Bound Tempo Under Nir Irradiation, Kristi L. St. Clair

University Honors Program Theses

Gold nanoparticles are of interest to a number of fields due to their size-dependent optical properties, high stability, and large surface area. The combination of these properties allows for a variety of uses including photothermal therapy, drug delivery and catalysis. Gold nanorods (GNR) absorb light of a given wavelength which stimulates the oscillation of electrons on the surface and is known as the surface plasmon resonance effect. The localized heating of rods via irradiation may cause enhanced effectiveness of an attached organic catalyst which allows the oxidation of alcohols to occur at room temperature. Previously, similar catalytic systems required high ...


Development Of Pre-Clinical Assays Based On Tandem Mass Spectrometry To Investigate Gabaa Receptor Modulators, Margaret Laurel Guthrie 2017 University of Wisconsin-Milwaukee

Development Of Pre-Clinical Assays Based On Tandem Mass Spectrometry To Investigate Gabaa Receptor Modulators, Margaret Laurel Guthrie

Theses and Dissertations

ABSTRACT

DEVELOPMENT OF PRE-CLINICAL ASSAYS BASED ON TANDEM MASS SPECTROMETRY TO INVESTIGATE GABAA RECEPTOR MODULATORS

by

Margaret L. Guthrie

The University of Wisconsin – Milwaukee, 2017

Under the Supervision of Professor Alexander (Leggy) Arnold

Drugs are compounds that interact with a biological system to produce a specific biological response. The goal of drug discovery is to design and synthesize a pharmaceutical agent that will produce a desired biological effect. However, the in-vivo effects of a drug molecule cannot be predicted without a variety of test results prior to human clinical trials. In order to designate any drug compound as a leading ...


Towards A Greater Understanding Of Post-Translational Modification Of Transcription Factor, Arsr, In Helicobacter Pylori Via Bottom-Up Proteomics: Methods Development For Electrospray And Nanospray Approaches, Theresa Gozzo 2017 College of William and Mary

Towards A Greater Understanding Of Post-Translational Modification Of Transcription Factor, Arsr, In Helicobacter Pylori Via Bottom-Up Proteomics: Methods Development For Electrospray And Nanospray Approaches, Theresa Gozzo

Undergraduate Honors Theses

Studies presented here work towards the analysis of post-translational modification of the essential ArsR transcription factor of Helicobacter pylori. A human health hazard, H. pylori contributes to the development of gastric cancer and peptic ulcers in its hosts. It is of interest to study the mechanisms that allow the bacterium to survive long term in the harsh stomach environment. The ArsRS signaling pathway mediates the repression of sabA, the gene coding for the adhesin protein, SabA, in acidic conditions. The repression is dependent on histidine kinase, ArsS, but independent of phosphorylation of ArsR at the canonical aspartic acid 52 (D52 ...


The Electrochemical Deposition Of Samarium And Europium Dissolved In Ionic Liquid Solvent, Bea Martinez 2017 University of Nevada, Las Vegas

The Electrochemical Deposition Of Samarium And Europium Dissolved In Ionic Liquid Solvent, Bea Martinez

UNLV Theses, Dissertations, Professional Papers, and Capstones

Rare-earth elements include the lanthanide series in the periodic table with the addition of scandium and yttrium. China produces approximately 95% of the world’s rare-earths supply and is the largest consumer of the world’s rare earth supply. Domestic production of rare-earth metals is a priority in the US. The domestic demand for rare-earth elements is largely based on their use in electronic devices, catalytic converters, and more importantly defense applications. Therefore, China’s monopoly of rare-earth elements is viewed as a threat to national security. Although capital investments have resulted in an increase in domestic mining and refining ...


Bioinformatic And Biophysical Analyses Of Proteins, Jonathan Catazaro 2017 University of Nebraska-Lincoln

Bioinformatic And Biophysical Analyses Of Proteins, Jonathan Catazaro

Student Research Projects, Dissertations, and Theses - Chemistry Department

The prevailing dogma in structural genomics is the existence of a strong correlation between protein sequence, structure, and biological function. Proteins with high sequence similarity typically have a similar, if not the same, structure and function. In many cases this logic can fail due to distantly related proteins having very low sequence similarity, a lack of a representative structure, structural novelty, or the absence of a characterized function. Further, the paradigm fails to account for dynamics, which have a significant effect on structural stability and enzymatic efficacy.

Nuclear magnetic resonance (NMR) spectroscopy is uniquely capable of solving the structure, assisting ...


Unmanned Aerial Systems For Monitoring Trace Tropospheric Gases, Travis J. Schuyler, Marcelo I. Guzman 2017 University of Kentucky

Unmanned Aerial Systems For Monitoring Trace Tropospheric Gases, Travis J. Schuyler, Marcelo I. Guzman

Chemistry Faculty Publications

The emission of greenhouse gases (GHGs) has changed the composition of the atmosphere during the Anthropocene. Accurately documenting the sources and magnitude of GHGs emission is an important undertaking for discriminating the contributions of different processes to radiative forcing. Currently there is no mobile platform that is able to quantify trace gases at altitudes(UASs) can be deployed on-site in minutes and can support the payloads necessary to quantify trace gases. Therefore, current efforts combine the use of UASs available on the civilian market with inexpensively designed analytical systems for monitoring atmospheric trace gases. In this context, this perspective introduces ...


Distinct Ice Patterns On Solid Surfaces With Various Wettabilities, Jie Liu, Chongqin Zhu, Kai Liu, Ying Jiang, Yanlin Song, Joseph S. Francisco, Xiao Cheng Zeng, Jianjun Wang 2017 Chinese Academy of Sciences

Distinct Ice Patterns On Solid Surfaces With Various Wettabilities, Jie Liu, Chongqin Zhu, Kai Liu, Ying Jiang, Yanlin Song, Joseph S. Francisco, Xiao Cheng Zeng, Jianjun Wang

Xiao Cheng Zeng Publications

No relationship has been established between surface wettability and ice growth patterns, although ice often forms on top of solid surfaces. Here, we report experimental observations obtained using a process specially designed to avoid the influence of nucleation and describe the wettability-dependent ice morphology on solid surfaces under atmospheric conditions and the discovery of two growth modes of ice crystals: along-surface and off-surface growth modes. Using atomistic molecular dynamics simulation analysis, we show that these distinct ice growth phenomena are attributable to the presence (or absence) of bilayer ice on solid surfaces with different wettability; that is, the formation of ...


Fabrication And Characterization Of Cuins₂ And Cuinse₂ Light-Absorbing Thin Films For Use In Solar Cells, Amy R. Tapley 2017 The University of Western Ontario

Fabrication And Characterization Of Cuins₂ And Cuinse₂ Light-Absorbing Thin Films For Use In Solar Cells, Amy R. Tapley

Electronic Thesis and Dissertation Repository

Solar energy is free and globally abundant and harnessed cost-effectively, it has the potential to be the world’s main source of energy. CuInGa(S,Se)2 solar cells have a very high efficiency of 20 %. However, gallium is a rare and expensive element. We have decided to work on its alternative CuInSe2 (CISe) and CuInS2 (CIS) by removing gallium or both gallium and selenium. The p-type CISe or CIS light-absorbing semiconducting layer is crucial for this type of solar cell. Preparation methods for CIS and CISe films were developed to reduce the costs and enhance the photoelectrochemical ...


Instrumental Aspects Of Oxygen Sensing: Quantitation And Recalibration Of A Biofouled Oxygen Sensor, Marlena Patrick 2017 University of Arkansas, Fayetteville

Instrumental Aspects Of Oxygen Sensing: Quantitation And Recalibration Of A Biofouled Oxygen Sensor, Marlena Patrick

Theses and Dissertations

In vivo oxygen sensing is a critical area of research for medical applications, such as ischemic stroke, but this important topic is not fully understood or resolved. In addition, the best method for calibration of in vivo sensors is as yet undetermined. For all implantable devices, biofouling, the adsorption of biological material to the device surface, is another significant problem with no clear or well-defined solution. One method employed is to apply a protective polymer membrane to the sensor surface in order to minimize the adsorption of biological material. The work described here investigates two polymers applied to a gold ...


Geochemical Fractionation, Speciation, And Bioavailability Of Heavy Metals In Stream Sediments In Aurora, Mo, Miles Pearson 2017 Missouri State University

Geochemical Fractionation, Speciation, And Bioavailability Of Heavy Metals In Stream Sediments In Aurora, Mo, Miles Pearson

MSU Graduate Theses

Stream sediments from Chat Creek in Aurora, MO, part of the former Tristate Mining District, were digested via a sequential extraction procedure modeled after the Tessier method. Prior sampling had shown elevated levels of zinc, lead, and cadmium in sediments located near former chat piles. Metals in sediments were divided into four geochemical fractions: 1) easily exchangeable, 2) carbonate-bound, 3) iron-manganese oxides-bound, and 4) organic matter-bound. The distribution of the metals within these fractions can help predict the bioavailability and speciation of said metals. The majority of metals were contained in the third and to a lesser extent the fourth ...


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