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Investigation Of Novel Electrolytes For Use In Lithium-Ion Batteries And Direct Methanol Fuel Cells, Kartik Pilar 2018 The Graduate Center, City University of New York

Investigation Of Novel Electrolytes For Use In Lithium-Ion Batteries And Direct Methanol Fuel Cells, Kartik Pilar

All Dissertations, Theses, and Capstone Projects

Energy storage and conversion plays a critical role in the efficient use of available energy and is crucial for the utilization of renewable energy sources. To achieve maximum efficiency of renewable energy sources, improvements to energy storage materials must be developed. In this work, novel electrolytes for secondary batteries and fuel cells have been studied using nuclear magnetic resonance and high pressure x-ray scattering techniques to form a better understanding of dynamic and structural properties of these materials. Ionic liquids have been studied due to their potential as a safer alternative to organic solvent-based electrolytes in lithium-ion batteries and composite ...


The Van Der Waals Fluid's Liquid Vapor Coexistence Locus, Carl W. David 2018 University of Connecticut

The Van Der Waals Fluid's Liquid Vapor Coexistence Locus, Carl W. David

Chemistry Education Materials

The liquid vapor coexistence locus is plotted from the analytical solution to the Maxwell construction for the van der Waals fluid.


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 ...


Call For Abstracts - Resrb 2018, June 18-20, Brussels, Belgium, Wojciech M. Budzianowski 2017 Wojciech Budzianowski Consulting Services

Call For Abstracts - Resrb 2018, June 18-20, Brussels, Belgium, Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.


Registration Form Resrb 2018, Wojciech M. Budzianowski 2017 Wojciech Budzianowski Consulting Services

Registration Form Resrb 2018, Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.


Abstract Template Resrb 2018, Wojciech M. Budzianowski 2017 Wojciech Budzianowski Consulting Services

Abstract Template Resrb 2018, Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.


Quantum Chemical Studies Of Noncovalent Interactions And Multicenter Bonds Utilizing Local Vibrational Modes, Vytor Oliveira 2017 Southern Methodist University

Quantum Chemical Studies Of Noncovalent Interactions And Multicenter Bonds Utilizing Local Vibrational Modes, Vytor Oliveira

Chemistry Theses and Dissertations

Noncovalent interactions play an important role for the design of novel drugs, better catalysts, synthesis of complex supramolecular structures, and so on. To develop new materials, a well-founded knowledge of how to control the strength of these interactions is desirable. Despite the many investigations done so far, a quantitative assessment of the intrinsic strength of most types of noncovalent interactions is still missing. Recently and for the first time, the Konkoli-Cremer local modes analysis was successfully used to probe the intrinsic strength of hydrogen and pnicogen bonds. We extended these investigations to more than 300 halogen and chalcogen bonds. A ...


Study Of 2,5-Diaminoimidazolone, A Mutagenic Product Of Oxidation Of Guanine In Dna, Hannah Catherine J. Pollard 2017 East Tennessee State University

Study Of 2,5-Diaminoimidazolone, A Mutagenic Product Of Oxidation Of Guanine In Dna, Hannah Catherine J. Pollard

Electronic Theses and Dissertations

2,5-diaminoimidazolone (Iz) is an important product of a 4-electron oxidation of guanine. The present research focuses on the mechanisms of formation of Iz via pathways initiated by guanine oxidation by one-electron oxidants (OEOs) generated by X-ray radiolysis in aqueous solutions. The kinetics of formation and yields of Iz in reactions of native highly polymerized DNA with different OEOs have been compared using an HPLC-based quantitative analysis of low-molecular products generated from the reaction of DNA-bound Iz with primary amines. Mechanisms of Iz formation in DNA have been investigated including oxygen and superoxide dependence as well as the hypothesis that ...


Eigenstate–Specific Temperatures In Two–Level Paramagnetic Spin Lattices, Mark Masthay, Calley N. Eads, Amber N. Johnson, R. Gerald Keil, Phillip Miller, Ross E. Jones, Joe D. Mashburn, Harry B. Fannin 2017 University of Dayton

Eigenstate–Specific Temperatures In Two–Level Paramagnetic Spin Lattices, Mark Masthay, Calley N. Eads, Amber N. Johnson, R. Gerald Keil, Phillip Miller, Ross E. Jones, Joe D. Mashburn, Harry B. Fannin

Chemistry Faculty Publications

Increasing interest in the thermodynamics of small and/or isolated systems, in combination with recent observations of negative temperatures of atoms in ultracold optical lattices, has stimulated the need for estimating the conventional, canonical temperature Tconvc of systems in equilibrium with heat baths using eigenstate-specific temperatures (ESTs). Four distinct ESTs—continuous canonical, discrete canonical, continuous microcanonical, and discrete microcanonical—are accordingly derived for two-level paramagnetic spin lattices (PSLs) in external magnetic fields. At large N, the four ESTs are intensive, equal to Tconvc, and obey all four laws of thermodynamics. In contrast, for N < 1000, the ESTs of most PSL eigenstates are non-intensive, differ from Tconvc, and violate each of the thermodynamic laws. Hence, in spite of their similarities to Tconvc at large N, the ESTs are not ...


Artificial Olfactory System For Multi-Component Analysis Of Gas Mixtures., Alexander Aleksandrovich Larin 2017 University of Louisville

Artificial Olfactory System For Multi-Component Analysis Of Gas Mixtures., Alexander Aleksandrovich Larin

Electronic Theses and Dissertations

Gas analysis is an important part of our world and gas sensing technology is becoming more essential for various aspects of our life. A novel approach for gas mixture analysis by using portable gas chromatography in combination with an array of highly integrated and selective metal oxide (MOX) sensors has been studied. We developed a system with small size (7 x 13 x 16 inches), low power consumption (~10 W) and absence of special carrier gases designed for portable field analysis (assuming apriori calibration). Low ppb and even sub-ppb level of detection for some VOCs was achieved during the analysis ...


Gamma-Radiation Induced Corrosion Of Alloy 800, Mojtaba Momeni 2017 The University of Western Ontario

Gamma-Radiation Induced Corrosion Of Alloy 800, Mojtaba Momeni

Electronic Thesis and Dissertation Repository

This thesis presents a newly developed mechanism and predictive model for the corrosion of Alloy 800. The Fe-Cr-Ni Alloy (Incoloy 800) is mainly used for steam generator (SG) tubing in CANDU and PWR reactors and is a candidate material for the proposed Canadian Supercritical Water Reactor (SCWR) in which it will be exposed to extreme conditions of high radiation flux and large temperature gradients. The influence of gamma radiation and water chemistry conditions on the corrosion behaviour of Alloy 800 are studied in this work. Ionizing radiation creates reducing (•eaq, •H, •O2-) and oxidizing radiolysis (•OH, H2 ...


Reorientations, Relaxations, Metastabilities, And Multidomains Of Skyrmion Lattices, L. J. Bannenberg, F. Qian, R. M. Dalgliesh, N. Martin, G. Chaboussant, M. Schmidt, Deborah L. Schlagel, Thomas A. Lograsso, Diamond Light Source Ltd., C. Pappas 2017 Delft University of Technology

Reorientations, Relaxations, Metastabilities, And Multidomains Of Skyrmion Lattices, L. J. Bannenberg, F. Qian, R. M. Dalgliesh, N. Martin, G. Chaboussant, M. Schmidt, Deborah L. Schlagel, Thomas A. Lograsso, Diamond Light Source Ltd., C. Pappas

Ames Laboratory Accepted Manuscripts

Magnetic skyrmions are nanosized topologically protected spin textures with particlelike properties. They can form lattices perpendicular to the magnetic field, and the orientation of these skyrmion lattices with respect to the crystallographic lattice is governed by spin-orbit coupling. By performing small-angle neutron scattering measurements, we investigate the coupling between the crystallographic and skyrmion lattices in both Cu2OSeO3 and the archetype chiral magnet MnSi. The results reveal that the orientation of the skyrmion lattice is primarily determined by the magnetic field direction with respect to the crystallographic lattice. In addition, it is also influenced by the magnetic history of the sample ...


Comparison Of S-Adsorption On (111) And (100) Facets Of Cu Nanoclusters, Jeffrey S. Boschen, Jiyoung Lee, Theresa L. Windus, James W. Evans, Patricia A. Thiel, Da-Jiang Liu 2017 Iowa State University

Comparison Of S-Adsorption On (111) And (100) Facets Of Cu Nanoclusters, Jeffrey S. Boschen, Jiyoung Lee, Theresa L. Windus, James W. Evans, Patricia A. Thiel, Da-Jiang Liu

Theresa Windus

In order to gain insight into the nature of chemical bonding of sulfur atoms on coinage metal surfaces, we compare the adsorption energy and structural parameters for sulfur at four-fold hollow (4fh) sites on (100) facets and at three-fold hollow (3fh) sites on (111) facets of Cu nanoclusters. Consistent results are obtained from localized atomic orbital and plane-wave based density functional theory using the same functionals. PBE and its hybrid counterpart (PBE0 or HSE06) also give similar results. 4fh sites are preferred over 3fh sites with stronger bonding by ∼0.6 eV for nanocluster sizes above ∼280 atoms. However, for ...


Combined Measurement Of Directional Raman Scattering And Surface-Plasmon-Polariton Cone From Adsorbates On Smooth Planar Gold Surfaces, Charles K.A. Nyamekye, Jonathan M. Bobbitt, Emily A. Smith 2017 Ames Laboratory

Combined Measurement Of Directional Raman Scattering And Surface-Plasmon-Polariton Cone From Adsorbates On Smooth Planar Gold Surfaces, Charles K.A. Nyamekye, Jonathan M. Bobbitt, Emily A. Smith

Emily Smith

Directional-surface-plasmon-coupled Raman scattering (directional RS) has the combined benefits of surface plasmon resonance and Raman spectroscopy, and provides the ability to measure adsorption and monolayer-sensitive chemical information. Directional RS is performed by optically coupling a 50-nm gold film to a Weierstrass prism in the Kretschmann configuration and scanning the angle of the incident laser under total internal reflection. The collected parameters on the prism side of the interface include a full surface-plasmon-polariton cone and the full Raman signal radiating from the cone as a function of incident angle. An instrument for performing directional RS and a quantitative study of the ...


Phase Behavior Of Binary And Polydisperse Suspensions Of Compressible Microgels Controlled By Selective Particle Deswelling, A. Scotti, U. Gasser, E. S. Herman, Jun Han, A. Menzel, L. Andrew Lyon, A. Fernandez-Nieves 2017 Paul Scherrer Institut

Phase Behavior Of Binary And Polydisperse Suspensions Of Compressible Microgels Controlled By Selective Particle Deswelling, A. Scotti, U. Gasser, E. S. Herman, Jun Han, A. Menzel, L. Andrew Lyon, A. Fernandez-Nieves

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

We investigate the phase behavior of suspensions of poly(N-isopropylacrylamide) (pNIPAM) microgels with either bimodal or polydisperse size distribution. We observe a shift of the fluid-crystal transition to higher concentrations depending on the polydispersity or the fraction of large particles in suspension. Crystallization is observed up to polydispersities as high as 18.5%, and up to a number fraction of large particles of 29% in bidisperse suspensions. The crystal structure is random hexagonal close-packed as in monodisperse pNIPAM microgel suspensions.We explain our experimental results by considering the effect of bound counterions. Above a critical particle concentration, these cause deswelling ...


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 ...


Avoiding The Cubic Equation In Finding The Van Der Waals Fluid's Vapor Pressures, Carl W. David 2017 University of Connecticut

Avoiding The Cubic Equation In Finding The Van Der Waals Fluid's Vapor Pressures, Carl W. David

Chemistry Education Materials

The van der Waals coexistence curve of liquid and vapor volumes as functions of the temperature (all in reduced coordinates) as well as the correspponding vapor pressures at these temperatures, is obtained using SageMath, a symbolic calculus/algebra computer programming language.The lack of correspondence of the coexistence locus’ analytical form as obtained herein and those of Lekner remains disconcerting.


Construction And Analysis Of Accurate Exchange-Correlation Potentials, Sviataslau V. Kohut 2017 The University of Western Ontario

Construction And Analysis Of Accurate Exchange-Correlation Potentials, Sviataslau V. Kohut

Electronic Thesis and Dissertation Repository

Practical Kohn–Sham density-functional calculations require approximations to the exchange-correlation energy functional, EXC[ρ], or the exchange-correlation potential, vXC(r), defined as the functional derivative of EXC[ρ] with respect to the electron density, ρ. This thesis focuses on the following problems: (i) development of approximate exchange-correlation potentials by modelling the exchange-correlation charge distribution; (ii) accurate approximation of functional derivatives of orbital-dependent functionals; (iii) generation of exchange-correlation potentials from many-electron wavefunctions; (iv) analysis of accurate exchange-correlation potentials in atoms and molecules.

The advantage of modelling the exchange-correlation potential through the exchange-correlation charge distribution, qXC(r), is ...


Nanoparticle-Based Drug-Delivery Systems Studied By Second Harmonic Generation, Raju Ram Kumal 2017 Louisiana State University and Agricultural and Mechanical College

Nanoparticle-Based Drug-Delivery Systems Studied By Second Harmonic Generation, Raju Ram Kumal

LSU Doctoral Dissertations

Second harmonic generation (SHG) is used to study different types of colloidal nanoparticle drug-delivery systems. The surface charge density, electrostatic surface potentials, and ion adsorptions of 50 nm colloidal gold nanoparticle samples coated with mercaptosuccinic acid are determined using SHG measurements under varying NaCl and MgCl2 concentrations in water. Numerical solutions to the spherical Poisson-Boltzmann equation are fit to the SHG results to account for the nanoparticle surface curvature and ion adsorption to the Stern layer interface, showing excellent agreement with electrophoretic mobility measurements. In another study, nanoparticles of gold, silver and polystyrene are functionalized with microRNA using a ...


Applying Machine Learning To Computational Chemistry: Can We Predict Molecular Properties Faster Without Compromising Accuracy?, Hanjing Xu, Pradeep Gurunathan, Lyudmila Slipchenko 2017 Purdue University

Applying Machine Learning To Computational Chemistry: Can We Predict Molecular Properties Faster Without Compromising Accuracy?, Hanjing Xu, Pradeep Gurunathan, Lyudmila Slipchenko

The Summer Undergraduate Research Fellowship (SURF) Symposium

Non-covalent interactions are crucial in analyzing protein folding and structure, function of DNA and RNA, structures of molecular crystals and aggregates, and many other processes in the fields of biology and chemistry. However, it is time and resource consuming to calculate such interactions using quantum-mechanical formulations. Our group has proposed previously that the effective fragment potential (EFP) method could serve as an efficient alternative to solve this problem. However, one of the computational bottlenecks of the EFP method is obtaining parameters for each molecule/fragment in the system, before the actual EFP simulations can be carried out. Here we present ...


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