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Solid-State Nmr Of Co2 Mineralization And Nmr Crystallography, Jinlei Cui 2019 Washington University in St. Louis

Solid-State Nmr Of Co2 Mineralization And Nmr Crystallography, Jinlei Cui

Arts & Sciences Electronic Theses and Dissertations

The work described in this dissertation has been accomplished by using solid-state nuclear magnetic resonance (SSNMR) spectroscopy to investigate CO2 mineralization and to refine the positions of protons in the crystalline system. The reaction of forsterite (Mg2SiO4) and 13CO2 is presented here, which is measured using in-situ 13C NMR spectroscopy without removing the sample from the reactor. 29Si SSNMR is used to investigate the reaction of forsterite with 13CO2 in the presence of water or NaCl brine as a function of depth in the sample. Additionally, we also show that NMR crystallography can significantly improve structure refinement of hydrogens’ positions ...


Using Molecular Dynamics To Study Qs21 Interactions And Penetration Of Lipid-Cholesterol Bilayers, Sarai Guerrero, Mikko Karttunen 2019 The University of Western Ontario

Using Molecular Dynamics To Study Qs21 Interactions And Penetration Of Lipid-Cholesterol Bilayers, Sarai Guerrero, Mikko Karttunen

Western Research Forum

Saponins have been used as adjuvant agents for decades in vaccines and therapies, but none are as well studied or heavily used as QS-21. This achievement is notwithstanding the fact that QS-21 usage is limited by its stability, toxicity, and scarcity. These shortcomings have only pushed researchers to develop and experiment with artificial recreations of the saponin to harness its unique benefits. A considerable number of research hours have been poured into this topic, but like QS-21 there is a shortcoming here as well. The number of articles that look at QS-21 interactions with the bilayer or the conditions under ...


Crystal Structure Of Zymonic Acid And A Redetermination Of Its Precursor, Pyruvic Acid, Dominik Heger, Alexis J. Eugene, Sean R. Parkin, Marcelo I. Guzman 2019 University of Kentucky

Crystal Structure Of Zymonic Acid And A Redetermination Of Its Precursor, Pyruvic Acid, Dominik Heger, Alexis J. Eugene, Sean R. Parkin, Marcelo I. Guzman

Chemistry Faculty Publications

The structure of zymonic acid (systematic name: 4-hy­droxy-2-methyl-5-oxo-2,5-di­hydro­furan-2-carb­oxy­lic acid), C6H6O5, which had previously eluded crystallographic determination, is presented here for the first time. It forms by intra­molecular condensation of parapyruvic acid, which is the product of aldol condensation of pyruvic acid. A redetermination of the crystal structure of pyruvic acid (systematic name: 2-oxo­propanoic acid), C3H4O3, at low temperature (90 K) and with increased precision, is also presented [for the previous structure, see: Harata et al. (1977). Acta Cryst. B33, 210–212 ...


The Investigation Of Methylidyne Radical (Ch) Reactions With Furan, 2-Methylfuran, And 2,5-Dimethlyfuran And The Photoionization And Photodissociation Of Valeric Acid, Erica Carrasco 2019 The University of San Francisco

The Investigation Of Methylidyne Radical (Ch) Reactions With Furan, 2-Methylfuran, And 2,5-Dimethlyfuran And The Photoionization And Photodissociation Of Valeric Acid, Erica Carrasco

Master's Theses

This thesis presents the combustion study of three furanic compounds using synchrotron radiation coupled with multiplexed photoionization mass spectrometry at 298 K. The experiments were performed at the Chemical Dynamics Beamline 9.0.2 at the Advanced Light Source of the Lawrence Berkeley National Laboratory. The reactions of the three furanic compounds with methylidyne (CH) radicals were analyzed based on their photoionization spectra and kinetic profiles.

Additionally, the unimolecular dissociation of valeric acid was also studied and presented in this work using the double imaging photoelectron photoion spectrometry (i2PEPICO) coupled with synchrotron radiation from the VUV beamline. The experiments were ...


Diffusional Dynamics Of Tetraalkylphosphonium Ionic Liquid Films Measured By Fluorescence Correlation Spectroscopy, Deyny L. Mendivelso-Perez, Muhammad Qamar Farooq, Kalyan Santra, Jared L. Anderson, Jacob W. Petrich, Emily A. Smith 2019 Iowa State University and Ames Laboratory

Diffusional Dynamics Of Tetraalkylphosphonium Ionic Liquid Films Measured By Fluorescence Correlation Spectroscopy, Deyny L. Mendivelso-Perez, Muhammad Qamar Farooq, Kalyan Santra, Jared L. Anderson, Jacob W. Petrich, Emily A. Smith

Emily Smith

Fluorescence correlation spectroscopy (FCS) is applied to investigate the diffusional dynamics of hydrophilic (Atto 590) and amphiphilic (DiD) fluorophores in a series of alkylphosphonium ionic liquid (IL) films ([P4448][Cl], [P6668][Cl], [P66614][Cl], and [P66614][NTf2]) in order to determine diffusional parameters and to elucidate nanoscale structural heterogeneities within the IL. From the measured correlation functions, the diffusion coefficients of the fluorescent molecules are estimated, rendering values that span from 0.39-1.2 and 0.146-5.2 µm2/s, for Atto 590 and DiD, respectively. A decrease in the diffusion coefficients is measured as the alkyl chain increases, coincident ...


Diffusional Dynamics Of Tetraalkylphosphonium Ionic Liquid Films Measured By Fluorescence Correlation Spectroscopy, Deyny L. Mendivelso-Perez, Muhammad Qamar Farooq, Kalyan Santra, Jared L. Anderson, Jacob W. Petrich, Emily A. Smith 2019 Iowa State University and Ames Laboratory

Diffusional Dynamics Of Tetraalkylphosphonium Ionic Liquid Films Measured By Fluorescence Correlation Spectroscopy, Deyny L. Mendivelso-Perez, Muhammad Qamar Farooq, Kalyan Santra, Jared L. Anderson, Jacob W. Petrich, Emily A. Smith

Jared L. Anderson

Fluorescence correlation spectroscopy (FCS) is applied to investigate the diffusional dynamics of hydrophilic (Atto 590) and amphiphilic (DiD) fluorophores in a series of alkylphosphonium ionic liquid (IL) films ([P4448][Cl], [P6668][Cl], [P66614][Cl], and [P66614][NTf2]) in order to determine diffusional parameters and to elucidate nanoscale structural heterogeneities within the IL. From the measured correlation functions, the diffusion coefficients of the fluorescent molecules are estimated, rendering values that span from 0.39-1.2 and 0.146-5.2 µm2/s, for Atto 590 and DiD, respectively. A decrease in the diffusion coefficients is measured as the alkyl chain increases, coincident ...


Dft Study On The Binding Of Selected Metal Ions With Phenylalanine Dipeptide, Ebtehal Alghamdi 2019 Atlanta University Center

Dft Study On The Binding Of Selected Metal Ions With Phenylalanine Dipeptide, Ebtehal Alghamdi

Electronic Theses & Dissertations Collection for Atlanta University & Clark Atlanta University

In this study, M06-2X/6-311+G(2d,2p) level calculations were performed to examine the binding energies and vibrational frequencies of different conformers of phenylalanine dipeptide interacting with metal ions (Na+, K+, Mg2+ and Ca2+). Four conformers were selected from the list of 20 most stable structures. The main goal was to understand the influence of conformers on the binding affinity of metal ions with different conformers of phenylalanine dipeptide. In agreement with experimental results, interactions of metal ions with two aromatic rings along with lone pair electrons of oxygen produced high stability. Binding energy was lowest for ...


A Theoretical Study Of The Electronic Structures Of Tetrahedral Boron-Halogen Complexes, Sahar Alshahrani 2019 Atlanta University Center

A Theoretical Study Of The Electronic Structures Of Tetrahedral Boron-Halogen Complexes, Sahar Alshahrani

Electronic Theses & Dissertations Collection for Atlanta University & Clark Atlanta University

This study addresses the structure and the bonding in the family of tetrahedral boranes. The specific molecules studied are the series B4X4 (X=H, F, Br, Cl, I), the series B4BrCl3, B4Br2Cl2, and B4Br3Cl and tetra-tert-butyl-tetraborane, t-Bu4B4. The research presented herein employs the Hartree-Fock Self Consistent Field (HFSCF), the Moller-Plesset second-order perturbation theory (MP2), and the Density Function Theory (DFT). A variety of basis sets was employed. Our calculations are the first theoretical studies of B4Br4, B4I ...


Coinage Metal–Sulfur Complexes: Stability On Metal(111) Surfaces And In The Gas Phase, Jiyoung Lee, Theresa L. Windus, Patricia A. Thiel, James W. Evans, Da-Jiang Liu 2019 Iowa State University and Ames Laboratory

Coinage Metal–Sulfur Complexes: Stability On Metal(111) Surfaces And In The Gas Phase, Jiyoung Lee, Theresa L. Windus, Patricia A. Thiel, James W. Evans, Da-Jiang Liu

James W. Evans

We provide a comprehensive theoretical assessment at the level of density functional theory (DFT) of the stability of various coinage metal–sulfur complexes, both in the gas phase and also for the complexes adsorbed on the (111) surface of the same coinage metal. Our primary interest lies in the latter where earlier scanning tunneling microscopy (STM) experiments were interpreted to suggest the existence of adsorbed S-decorated metal trimers, sometimes as a component of more complex adlayer structures. Recent STM studies at 5 K directly observed other isolated adsorbed metal–sulfur complexes. For these adsorbed species, we calculate various aspects of ...


Coinage Metal–Sulfur Complexes: Stability On Metal(111) Surfaces And In The Gas Phase, Jiyoung Lee, Theresa L. Windus, Patricia A. Thiel, James W. Evans, Da-Jiang Liu 2019 Iowa State University and Ames Laboratory

Coinage Metal–Sulfur Complexes: Stability On Metal(111) Surfaces And In The Gas Phase, Jiyoung Lee, Theresa L. Windus, Patricia A. Thiel, James W. Evans, Da-Jiang Liu

Patricia A. Thiel

We provide a comprehensive theoretical assessment at the level of density functional theory (DFT) of the stability of various coinage metal–sulfur complexes, both in the gas phase and also for the complexes adsorbed on the (111) surface of the same coinage metal. Our primary interest lies in the latter where earlier scanning tunneling microscopy (STM) experiments were interpreted to suggest the existence of adsorbed S-decorated metal trimers, sometimes as a component of more complex adlayer structures. Recent STM studies at 5 K directly observed other isolated adsorbed metal–sulfur complexes. For these adsorbed species, we calculate various aspects of ...


Coinage Metal–Sulfur Complexes: Stability On Metal(111) Surfaces And In The Gas Phase, Jiyoung Lee, Theresa L. Windus, Patricia A. Thiel, James W. Evans, Da-Jiang Liu 2019 Iowa State University and Ames Laboratory

Coinage Metal–Sulfur Complexes: Stability On Metal(111) Surfaces And In The Gas Phase, Jiyoung Lee, Theresa L. Windus, Patricia A. Thiel, James W. Evans, Da-Jiang Liu

Theresa Windus

We provide a comprehensive theoretical assessment at the level of density functional theory (DFT) of the stability of various coinage metal–sulfur complexes, both in the gas phase and also for the complexes adsorbed on the (111) surface of the same coinage metal. Our primary interest lies in the latter where earlier scanning tunneling microscopy (STM) experiments were interpreted to suggest the existence of adsorbed S-decorated metal trimers, sometimes as a component of more complex adlayer structures. Recent STM studies at 5 K directly observed other isolated adsorbed metal–sulfur complexes. For these adsorbed species, we calculate various aspects of ...


Characteristics Of Sulfur Atoms Adsorbed On Ag(100), Ag(110), And Ag(111) As Probed With Scanning Tunneling Microscopy: Experiment And Theory, Peter M. Spurgeon, Da-Jiang Liu, Holly Walen, Junepyo Oh, Hyun Jin Yang, Yousoo Kim, Patricia A. Thiel 2019 Iowa State University

Characteristics Of Sulfur Atoms Adsorbed On Ag(100), Ag(110), And Ag(111) As Probed With Scanning Tunneling Microscopy: Experiment And Theory, Peter M. Spurgeon, Da-Jiang Liu, Holly Walen, Junepyo Oh, Hyun Jin Yang, Yousoo Kim, Patricia A. Thiel

Patricia A. Thiel

In this paper, we report that S atoms on Ag(100) and Ag(110) exhibit a distinctive range of appearances in scanning tunneling microscopy (STM) images, depending on the sample bias voltage, VS. Progressing from negative to positive VS, the atomic shape can be described as a round protrusion surrounded by a dark halo (sombrero) in which the central protrusion shrinks, leaving only a round depression. This progression resembles that reported previously for S atoms on Cu(100). We test whether DFT can reproduce these shapes and the transition between them, using a modified version of the Lang–Tersoff–Hamann ...


Defect Chemistry And Ion Intercalation During The Growth And Solid-State Transformation Of Metal Halide Nanocrystals, Bo Yin 2019 Washington University in St. Louis

Defect Chemistry And Ion Intercalation During The Growth And Solid-State Transformation Of Metal Halide Nanocrystals, Bo Yin

Engineering and Applied Science Theses & Dissertations

Abstract of the Dissertation

Defect Chemistry and Ion Intercalation During the Growth and Solid-State Transformation of Metal Halide Nanocrystals

Semiconductor metal halides as light-sensitive materials have applications in multiple areas, such as photographic film, antibacterial agents and photocatalysts. One focus of this dissertation is to achieve novel morphologies of ternary silver bromoiodide (AgBr1-xIx, 0

For the silver halide system, we demonstrate that the anion composition of AgBr1-xIx nanocrystals determines their shape through the introduction of twin defects as the nanocrystals are made more iodide-rich. AgBr1-xIx nanocrystals grow as single-phase, solid solutions with the rock salt crystal structure for anions compositions ...


Recycling Aluminum, Steffani Burwitz, Kristin M. Roe, Matthew L. Miller, Madhav P. Nepal, Larry B. Browning, P. Troy White 2019 West Central High School, Humboldt, SD

Recycling Aluminum, Steffani Burwitz, Kristin M. Roe, Matthew L. Miller, Madhav P. Nepal, Larry B. Browning, P. Troy White

Madhav Nepal

Students will investigate and compare the energy cost to produce aluminum products from aluminum ore and recycled aluminum. Students will perform an electrolysis activity to reinforce the idea that recycling metal requires less energy than mining and refining metals from their original source in the earth.


Optical Memory Behavior, Metallophilic Luminescence, And Chemical Sensing Ability Of Inorganic And Organometallic Complexes: Development Of Optoelectronic Materials, Aaron D. Nicholas 2019 University of Maine

Optical Memory Behavior, Metallophilic Luminescence, And Chemical Sensing Ability Of Inorganic And Organometallic Complexes: Development Of Optoelectronic Materials, Aaron D. Nicholas

Electronic Theses and Dissertations

This dissertation is divided into three sections: (1) optical memory, (2) metallophilic-based luminescence, and (3) chemical sensors. (1) Optical memory behavior of d10metal Cu(I) thiocyanate salts are investigated to explore their potential use in the development of digital data storage devices. From this study we have discovered a new class of CuSCN(3-BrPy)2optical memory material which undergo a reduction in emission intensity upon laser irradiation. This loss of emission intensity can be reversed simply by heating the sample to room temperature. The mechanism by which this emission loss occurs has been studied, revealing a migrating ...


Characteristics Of Sulfur Atoms Adsorbed On Ag(100), Ag(110), And Ag(111) As Probed With Scanning Tunneling Microscopy: Experiment And Theory, Peter M. Spurgeon, Da-Jiang Liu, Holly Walen, Junepyo Oh, Hyun Jin Yang, Yousoo Kim, Patricia A. Thiel 2019 Iowa State University

Characteristics Of Sulfur Atoms Adsorbed On Ag(100), Ag(110), And Ag(111) As Probed With Scanning Tunneling Microscopy: Experiment And Theory, Peter M. Spurgeon, Da-Jiang Liu, Holly Walen, Junepyo Oh, Hyun Jin Yang, Yousoo Kim, Patricia A. Thiel

Chemistry Publications

In this paper, we report that S atoms on Ag(100) and Ag(110) exhibit a distinctive range of appearances in scanning tunneling microscopy (STM) images, depending on the sample bias voltage, VS. Progressing from negative to positive VS, the atomic shape can be described as a round protrusion surrounded by a dark halo (sombrero) in which the central protrusion shrinks, leaving only a round depression. This progression resembles that reported previously for S atoms on Cu(100). We test whether DFT can reproduce these shapes and the transition between them, using a modified version of the Lang–Tersoff–Hamann ...


Neurological Disease Detection Using Surface Enhanced Spatially Offset Raman Spectroscopy (Sesors), Taylor D. Payne 2019 University of Tennessee- Knoxville

Neurological Disease Detection Using Surface Enhanced Spatially Offset Raman Spectroscopy (Sesors), Taylor D. Payne

Chancellor’s Honors Program Projects

No abstract provided.


Computational Studies Of Small Molecule Activation In Catylsis And Green Chemistry, Alexa N. Griffith Ms. 2019 University of Tennessee, Knoxville

Computational Studies Of Small Molecule Activation In Catylsis And Green Chemistry, Alexa N. Griffith Ms.

Chancellor’s Honors Program Projects

No abstract provided.


Characterizing Flame-Resistant Polymers Using Single-Sided Nmr, Anna Tsutsui 2019 William & Mary

Characterizing Flame-Resistant Polymers Using Single-Sided Nmr, Anna Tsutsui

Undergraduate Honors Theses

Many commonly used polymers are inherently flammable. Manufacturers have been able to make polymers more flame-resistant by incorporating additives in polymer matrices. Current testing methods of these materials are destructive. As a result, there is a lack of data that can characterize the long-term effects of thermal exposure on these materials. This study presents single-sided NMR as an alternative technique to characterize the physical properties of these materials before and after thermal exposure. From single-sided NMR, this study finds that it is possible to characterize the molecular behavior of flame-resistant polymers and that additives cause no significant physical change to ...


Spatial Encoding With Single-Sided Nmr, Madeline Brass 2019 William & Mary

Spatial Encoding With Single-Sided Nmr, Madeline Brass

Undergraduate Honors Theses

Single-sided NMR is an important non-invasive, non-destructive technique used to characterize molecules. Specifically, single-sided NMR has applications in biomedicine, elastomers, solid polymers, moisture in porous media, and cultural heritage. Single-sided magnets can be used to analyze T2 relaxation to gauge the relative motion of molecules in the sample. However, the are few methods to characterize heterogeneous samples with single-sided NMR. Most experiments take one set of data for the entire sample regardless if the sample is heterogeneous or homogeneous. New methods to spatially encode with single-sided NMR were explore and characterized based on their advantages and disadvantages. These methods include ...


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