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Synthesis And Characterization Of Cyclodextrin Functionalized Ionic Liquid Polymer For The Extraction Of Phenols / Muggundha Raoov A/L Ramachandran, Muggundha Raoov Ramachandran Jan 2015

Synthesis And Characterization Of Cyclodextrin Functionalized Ionic Liquid Polymer For The Extraction Of Phenols / Muggundha Raoov A/L Ramachandran, Muggundha Raoov Ramachandran

Student Works (2010-2019)

β-Cyclodextrin functionalized ionic liquid polymer (βCD-BIMOTs-TDI) was first synthesized by functionalized β-cyclodextrin (CD) with 1-benzylimidazole (BIM) to form monofunctionalized CD (βCD-BIMOTs), and was further polymerized using toluene diisocyanate (TDI) as a linker to form insoluble βCD-BIMOTs-TDI. The βCDBIMOTs- TDI was characterized using various tools and the results obtained were compared with those derived from the native β-cyclodextrin polymer (βCD-TDI). The scanning electron microscope (SEM) results showed that the presence of ionic liquid (IL) increased the pore size, while the thermo gravimetric analysis (TGA) results showed that the presence of IL increased the stability of the βCD-BIMOTs-TDI. Meanwhile, Brunauer-Emmett-Teller (BET) result …


Preparation And Characterization Of Self-Assembled Monolayers And Mesoscale Protein Patterning, Panae Noomuna Jan 2015

Preparation And Characterization Of Self-Assembled Monolayers And Mesoscale Protein Patterning, Panae Noomuna

Online Theses and Dissertations

Bottom-up approach was used to develop self-assembled monolayers of octadecyltrichlorosilane (OTS) and undecenyltrichlorosilane(UTS) on Si(100) wafer. Undecenyltrichlorosilane monolayer was oxidized at the vinyl terminal to generate a carboxylic acid group. Lysozyme protein was immobilized on the polar carboxylic acid group. The developed protein patterns were investigated using fluorescence microscopy. Lysozyme has an isoelectronic point of 11.35. At a pH below this value the protein is positively charged making it a good candidate for electrostatic adsorption on the negatively charge -COO- group. Fluorescence images confirm formation of lysozyme across the silicon wafer. The patterned Si(100) wafer can be used as a …


Upper Tropospheric Ozone Production From Lightning NoX-Impacted Convection: Smoke Ingestion Case Study From The Dc3 Campaign, E. C. Apel, R. S. Hornbrook, A. J. Hills, N. J. Blake, M. C. Barth, A. Weinheimer, C. Cantrell, S. A. Rutledge, B. Basarab, J. Crawford, G. Diskin, C. R. Homeyer, T. Campos, F. Flocke, A. Fried, D. R. Blake, W. Brune, I. Pollack, J. Peischl, T. Ryerson, P. O. Wennberg, J. D. Crounse, A. Wisthaler, T. Mikoviny, G. Huey, B. Heikes, D. O'Sullivan, D. D. Riemer Jan 2015

Upper Tropospheric Ozone Production From Lightning NoX-Impacted Convection: Smoke Ingestion Case Study From The Dc3 Campaign, E. C. Apel, R. S. Hornbrook, A. J. Hills, N. J. Blake, M. C. Barth, A. Weinheimer, C. Cantrell, S. A. Rutledge, B. Basarab, J. Crawford, G. Diskin, C. R. Homeyer, T. Campos, F. Flocke, A. Fried, D. R. Blake, W. Brune, I. Pollack, J. Peischl, T. Ryerson, P. O. Wennberg, J. D. Crounse, A. Wisthaler, T. Mikoviny, G. Huey, B. Heikes, D. O'Sullivan, D. D. Riemer

United States National Aeronautics and Space Administration: Publications

As part of the Deep Convective Cloud and Chemistry (DC3) experiment, the National Science Foundation/National Center for Atmospheric Research (NCAR) Gulfstream-V (GV) and NASA DC-8 research aircraft probed the chemical composition of the inflow and outflow of two convective storms (north storm, NS, south storm, SS) originating in the Colorado region on 22 June 2012, a time when the High Park wildfire was active in the area. A wide range of trace species were measured on board both aircraft including biomass burning (BB) tracers hydrogen cyanide (HCN) and acetonitrile (ACN). Acrolein, a much shorter lived tracer for BB, was also …


Upper Tropospheric Ozone Production From Lightning NoX‐ Impacted Convection: Smoke Ingestion Case Study From The Dc3 Campaign, E. C. Apel, R. S. Hornbrook, A. J. Hills, N. J. Blake, M. C. Barth, A. Weinheimer, C. Cantrell, S. A. Rutledge, B. Basarab, J. Crawford, G. Diskin, C. R. Homeyer, T. Campos, F. Flocke, A. Fried, D. R. Blake, W. Brune, I. Pollack, J. Peischl, T. Ryerson, P. O. Crounse, A. Wisthaler, T. Mikoviny, G. Huey, Brian G. Heikes, D. O'Sullivan, D. D. Riemer Jan 2015

Upper Tropospheric Ozone Production From Lightning NoX‐ Impacted Convection: Smoke Ingestion Case Study From The Dc3 Campaign, E. C. Apel, R. S. Hornbrook, A. J. Hills, N. J. Blake, M. C. Barth, A. Weinheimer, C. Cantrell, S. A. Rutledge, B. Basarab, J. Crawford, G. Diskin, C. R. Homeyer, T. Campos, F. Flocke, A. Fried, D. R. Blake, W. Brune, I. Pollack, J. Peischl, T. Ryerson, P. O. Crounse, A. Wisthaler, T. Mikoviny, G. Huey, Brian G. Heikes, D. O'Sullivan, D. D. Riemer

Graduate School of Oceanography Faculty Publications

As part of the Deep Convective Cloud and Chemistry (DC3) experiment, the National Science Foundation/National Center for Atmospheric Research (NCAR) Gulfstream‐V (GV) and NASA DC‐8 research aircraft probed the chemical composition of the inflow and outflow of two convective storms (north storm, NS, south storm, SS) originating in the Colorado region on 22 June 2012, a time when the High Park wildfire was active in the area. A wide range of trace species were measured on board both aircraft including biomass burning (BB) tracers hydrogen cyanide (HCN) and acetonitrile (ACN). Acrolein, a much shorter lived tracer for BB, was also …


Nmr T₁ Studies Of Colloidal Unimolecular Polymer (Cup) Surface Water, Yousef Abobaker Dawib Jan 2015

Nmr T₁ Studies Of Colloidal Unimolecular Polymer (Cup) Surface Water, Yousef Abobaker Dawib

Doctoral Dissertations

"This dissertation is subdivided into three topics: Experimental study of colloidal unimolecular polymer (CUP) hydration; probing of polymer chain dynamics by 13C solid state NMR technique; and the anticorrosive effect of 5-mercapto-1, 3, 4-thiadiazole-2(3H)-thione (MTT) derivatives.

The states of water in colloidal unimolecular polymer system were investigated by low field proton NMR. Bound and free water fractions were determined using spin-lattice relaxation measurements. A model equation was used to analyze the inversion recovery data.

The proton cross polarization and the pulse sequence for total spinning sideband suppression CP-TOSS NMR method were developed to determine the chain mobility of polymers …


The Effectiveness Of Online Homework Tutorials As Compared To Pen And Paper Tutorials, Molly Shuman Jan 2015

The Effectiveness Of Online Homework Tutorials As Compared To Pen And Paper Tutorials, Molly Shuman

LSU Master's Theses

The purpose of this study was to determine if students learn more from completing web based homework (WBHW) compared to completing homework by traditional means with pen and paper. Determining the efficacy of WBHW is important because many schools are being pressured to implement technology in the classroom. To determine the effectiveness of WBHW, student normalized learning gains were calculated from pre and post-test scores for 62 students. Learning gains were then compared when students completed WBHW, traditional homework, or did not complete homework at all, over four units in a high school chemistry class. No difference in learning gains …


Chemically Patterned Surfaces As Test Platforms To Study Magnetic And Solvent-Responsive Properties At The Nanoscale: Investigations Using Scanning Probe Microscopy, Shalaka Kulkarni Jan 2015

Chemically Patterned Surfaces As Test Platforms To Study Magnetic And Solvent-Responsive Properties At The Nanoscale: Investigations Using Scanning Probe Microscopy, Shalaka Kulkarni

LSU Doctoral Dissertations

Chemically patterned surfaces were fabricated using a combination of molecular self-assembly and particle lithography to generate billions of nanostructures of organosilane self-assembled monolayers (SAMs). Monodisperse mesospheres were used as surface masks to prepare nanostructures on flat surfaces using the simple benchtop chemistry steps of mixing, centrifuging, evaporation, and drying. Periodic arrays of well-defined organosilane nanostructures serve as discrete surface sites for the selective deposition of polymers and magnetic nanoparticles.

In this dissertation, particle lithography approaches for surface patterning provide new directions for studying surface chemistry at the molecular-level using high resolution investigations with scanning probe microscopy (SPM). Atomic force microscopy …


Surface Chemistry And Spectroscopy Of Human Insulin Langmuir Monolayer, Sheba Johnson Dec 2014

Surface Chemistry And Spectroscopy Of Human Insulin Langmuir Monolayer, Sheba Johnson

Open Access Dissertations

The focus of this thesis can be categorized as study of two molecules, namely human insulin and carbon dots at 1) air-water interface as a Langmuir monolayer and 2) in solution. Aggregation of proteins into amyloids has been related to several diseases like Alzheimer’s, Parkinson’s and Amyloidosis. Human insulin was chosen as a model protein to study fibrillation of the proteins. Effect of carbon dots on the rate of human insulin fibrillation was examined through spectroscopic techniques and imaging. Both human insulin and carbon dots were examined at air-water interface as a Langmuir monolayer. The conformation of human insulin in …


Mole Street Journal, December 2014, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry Dec 2014

Mole Street Journal, December 2014, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.


Kinetic Experimental And Modeling Studies On Iron-Based Catalysts Promoted With Lanthana For The High-Temperature Water-Gas Shift Reaction Characterized With Operando Uv-Visible Spectroscopy And For The Fischer-Tropsch Synthesis, Basseem Bishara Hallac Dec 2014

Kinetic Experimental And Modeling Studies On Iron-Based Catalysts Promoted With Lanthana For The High-Temperature Water-Gas Shift Reaction Characterized With Operando Uv-Visible Spectroscopy And For The Fischer-Tropsch Synthesis, Basseem Bishara Hallac

Theses and Dissertations

The structural and functional roles of lanthana in unsupported iron-based catalysts for the high-temperature water-gas shift reaction and Fischer-Tropsch synthesis were investigated. The performance of the catalysts with varying lanthana contents was based on their activity, selectivity, and stability. With regard to the former reaction, extent of reduction of the iron in Fe2O3/Cr2O3/CuO/La2O3 water-gas shift catalysts is a key parameter that was characterized using UV-visible spectroscopy. Minor addition of lanthana (<0.5 wt%) produces more active and stable catalysts apparently because it stabilizes the iron-chromium spinel, increases the surface area of the reduced catalysts, enhances the reduction of hematite to the magnetite active phase, and facilitates the adsorption of CO on the surface of the catalyst modeled by an adsorptive Langmuir-Hinshelwood mechanism. Statistical 95% confidence contour plots of the adsorption equilibrium constants show that water adsorbs more strongly than CO, which inhibits the reaction rate. A calibration curve that correlates the oxidation state of surface iron domains to normalized absorbance of visible light was successfully generated and applied to the water-gas shift catalysts. UV-visible studies indicated higher extent of reduction for surface Fe domains for the catalysts promoted with 1 wt% of lanthana and showed potential to be a more convenient technique for surface chemistry studies than X-ray absorption near edge spectroscopy (XANES). Lanthana addition to iron-based Fischer-Tropsch catalysts enhances the olefin-to-paraffin ratio, but decreases their activity, stability, and selectivity to liquid hydrocarbons. Adding lanthana at the expense of potassium reduces the water-gas shift selectivity and enhances the activity and stability of the catalysts. Finally, a model that simulates heat and mass transfer limitations on the particle scale for the Fischer-Tropsch reaction applicable at lab-scale suggests optimal operating and design conditions of 256°C, 30 bar, and 80 mirons are recommended for higher selectivity to liquid hydrocarbons. The model considers pressure drop, deactivation, pore diffusion, film heat transfer, and internal heat transfer when solving for the optimal conditions, and maps them as functions of design variables. This model can be up-scaled to provide guidance for optimal design of commercial-size reactors.


Sign Me Up! Determining Motivation For High School Chemistry Students Enrolling In A Second Year Chemistry Course, Nilda N. Camarena Dec 2014

Sign Me Up! Determining Motivation For High School Chemistry Students Enrolling In A Second Year Chemistry Course, Nilda N. Camarena

Theses and Dissertations - UTB/UTPA

A sample of 108 Pre-AP Chemistry students in Texas participated in a study to determine motivational factors for enrolling in AP Chemistry and University Chemistry. The factors measured were academic attitude, perceptions of chemistry, confidence level in chemistry, and expectations/experiences in the chemistry class. Students completed two questionnaires, one at the beginning of the year and one at the end. Four high school campuses from two school districts in Texas participated. Two campuses were traditional high schools and two were smaller magnet schools. The results from this study are able to confirm that there are definite correlations between academic attitudes, …


Um Vice Chancellor Honored As Prestigious Aaas Fellow, Mitchell Diggs Nov 2014

Um Vice Chancellor Honored As Prestigious Aaas Fellow, Mitchell Diggs

University of Mississippi News

Alice Clark cited for research achievements, service to National Institutes of Health


Evaluation And Application Of Instruments Measuring Spatial Ability And Attitude For College Chemistry Students, Xiaoying Xu Nov 2014

Evaluation And Application Of Instruments Measuring Spatial Ability And Attitude For College Chemistry Students, Xiaoying Xu

USF Tampa Graduate Theses and Dissertations

Student performance in college chemistry courses remains a concern for educators seeking to help improve the future STEM workforce. Besides math ability and prior chemistry knowledge, spatial ability and attitude toward chemistry have been considered as important factors influencing college chemistry performance. This work includes five studies and uses data collected from instruments to examine the relationships of these two factors - spatial ability and attitude - with student chemistry performance, and provides psychometric evidence for using the Purdue Visualization of Rotations test (ROT) and Attitude toward the Subject of Chemistry Inventory (ASCIv2) to measure these two factors, respectively, in …


Mole Street Journal, October 2014, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry Nov 2014

Mole Street Journal, October 2014, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.


Mole Street Journal, September 2014, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry Oct 2014

Mole Street Journal, September 2014, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.


Design, Synthesis And Biological Evaluation Of Small Molecule Inhibitors Of The Hedgehog Signaling Pathway, Upasana Banerjee Sep 2014

Design, Synthesis And Biological Evaluation Of Small Molecule Inhibitors Of The Hedgehog Signaling Pathway, Upasana Banerjee

Doctoral Dissertations

The Hedgehog (Hh) signaling is an important embryonic developmental pathway normally responsible for tissue growth, differentiation and patterning. However, aberrant activity of this signaling cascade has been implicated in several types of cancer. Therefore, inhibition of the dysregulated pathway is a promising therapeutic target for treating Hh-dependent malignancies such as basal cell carcinoma (BCC) and medulloblastoma (MB). Previous studies resulted in the FDA approval of Vismodegib, a small molecule inhibitor of the Hh pathway, for the treatment of advanced BCC. Similarly, several other small molecule Hh antagonists have progressed into clinical trials. Moreover, several components within the Hh pathway have …


Mole Street Journal, August 2014, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry Sep 2014

Mole Street Journal, August 2014, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.


Chmy 221.01: Organic Chemistry I, Nigel D. Priestley Sep 2014

Chmy 221.01: Organic Chemistry I, Nigel D. Priestley

University of Montana Course Syllabi

No abstract provided.


Neuroinflammation And Neurologic Deficits In Diabetes Linked To Brain Accumulation Of Amylin, Sarah Srodulski, Savita Sharma, Adam B. Bachstetter, Jennifer M. Brelsfoard, Conrado Pascual, Xinmin Simon Xie, Kathryn E. Saatman, Linda J. Van Eldik, Florin Despa Aug 2014

Neuroinflammation And Neurologic Deficits In Diabetes Linked To Brain Accumulation Of Amylin, Sarah Srodulski, Savita Sharma, Adam B. Bachstetter, Jennifer M. Brelsfoard, Conrado Pascual, Xinmin Simon Xie, Kathryn E. Saatman, Linda J. Van Eldik, Florin Despa

Pharmacology and Nutritional Sciences Faculty Publications

BACKGROUND: We recently found that brain tissue from patients with type-2 diabetes (T2D) and cognitive impairment contains deposits of amylin, an amyloidogenic hormone synthesized and co-secreted with insulin by pancreatic β-cells. Amylin deposition is promoted by chronic hypersecretion of amylin (hyperamylinemia), which is common in humans with obesity or pre-diabetic insulin resistance. Human amylin oligomerizes quickly when oversecreted, which is toxic, induces inflammation in pancreatic islets and contributes to the development of T2D. Here, we tested the hypothesis that accumulation of oligomerized amylin affects brain function.

METHODS: In contrast to amylin from humans, rodent amylin is neither amyloidogenic nor cytotoxic. …


Mole Street Journal, July 2014, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry Aug 2014

Mole Street Journal, July 2014, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.


Electron Transfer In Pnicogen Bond, Liangyu Guan Aug 2014

Electron Transfer In Pnicogen Bond, Liangyu Guan

Masters Theses

Abstract is available for download as a separate file.


Synthesis, Design, And Environmental Fate Of Metallic Nanoparticles, Ashley E. Hart Aug 2014

Synthesis, Design, And Environmental Fate Of Metallic Nanoparticles, Ashley E. Hart

All Dissertations

Rational design of nanoparticle surface chemistry offers the ability to control nanoparticle characteristics such as size, polydispersity, shape, dispersibility in various solvents, functionality and end fate. Ligand exchange has proved to be is a versatile method for modifying the surface of plasmonic nanoparticles. Ligand exchange has provided a “green” alternative to traditional biphasic syntheses that require large amounts of phase transfer catalysts. Ligand exchange can also be used to reduce the amount of post synthesis processing and waste when it is conducted on nanoparticles that have been synthesized with a method that affords control over nanoparticle size and polydispersity. Ligand …


Mole Street Journal, June 2014, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry Jul 2014

Mole Street Journal, June 2014, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.


Neutral Networks Of Real-World Programs And Their Application To Automated Software Evolution, Eric Schulte Jul 2014

Neutral Networks Of Real-World Programs And Their Application To Automated Software Evolution, Eric Schulte

Computer Science ETDs

The existing software development ecosystem is the product of evolutionary forces, and consequently real-world software is amenable to improvement through automated evolutionary techniques. This dissertation presents empirical evidence that software is inherently robust to small randomized program transformations, or 'mutations. Simple and general mutation operations are demonstrated that can be applied to software source code, compiled assembler code, or directly to binary executables. These mutations often generate variants of working programs that differ significantly from the original, yet remain fully functional. Applying successive mutations to the same software program uncovers large 'neutral networks' of fully functional variants of real-world software …


Mole Street Journal, May 2014, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry Jun 2014

Mole Street Journal, May 2014, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.


Mole Street Journal, April 2014, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry May 2014

Mole Street Journal, April 2014, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.


Exploring Students' Perceptions And Performance On Predict-Observe-Explain Tasks In High School Chemistry Laboratory, Praveen Vadapally May 2014

Exploring Students' Perceptions And Performance On Predict-Observe-Explain Tasks In High School Chemistry Laboratory, Praveen Vadapally

Dissertations

This study sought to understand the impact of gender and reasoning level on students’ perceptions and performances of Predict-Observe-Explain (POE) laboratory tasks in a high school chemistry laboratory. Several literature reviews have reported that students at all levels have not developed the specific knowledge and skills that were expected from their laboratory work. Studies conducted over the last several decades have found that boys tend to be more successful than girls in science and mathematics courses. However, some recent studies have suggested that girls may be reducing this gender gap. This gender difference is the focal point of this research …


Design Optimization Of A Composite Wing Box For High-Altitude Long-Endurance Aircraft, Philip T. Arévalo May 2014

Design Optimization Of A Composite Wing Box For High-Altitude Long-Endurance Aircraft, Philip T. Arévalo

Doctoral Dissertations and Master's Theses

A design optimization process is developed to define the wing box structure for High-Altitude Long-Endurance Aircraft (HALE). The goal of this study is to determine the best tradeoff between mass and rigidity of a HALE aircraft wing structure. A preliminary composite laminate structural design procedure is described which uses a NASTRAN-based Finite Element Analysis (FEA), and the Hierarchical Evolutionary Engineering Design System (HEEDS) MDO software to define a locus of acceptable, optimized wing box design definitions.


The Wooster Voice (Wooster, Oh), 2014-04-25, Wooster Voice Editors Apr 2014

The Wooster Voice (Wooster, Oh), 2014-04-25, Wooster Voice Editors

The Voice: 2012-Present

News articles in this issue of the Voice are "Students petition for new counselor" for better resources for LGBTQ+ students, "Student groups commemorate Galpin Takeover 25-year anniversary," "Student threatened by motorist with violence and racial epithets," "Dining Services to change smoothie selection next fall," and "Security presence increased at Lip Sync, results disputed." In Features, there are articles on I.S. Symposium, Luce Scholarship recipients, the Physics Club's Community Science Day, WOO91's Cornhole Tournament, and the Humans of Wooster. The Arts and Entertainment section has articles on Springfest and the Goliard Literary Magazine. In Sports, there are articles on women's lacrosse, …


Mole Street Journal, March 2014, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry Apr 2014

Mole Street Journal, March 2014, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.