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Full-Text Articles in Physics

Study Of Diffusion, Solubility And Electrophysical Properties Of Scandium, Praseodymium And Europium In Silicon, Sirojiddin Z. Zainabidinov, Dilshad E. Nazyrov, Valentina P. Usacheva Jun 2020

Study Of Diffusion, Solubility And Electrophysical Properties Of Scandium, Praseodymium And Europium In Silicon, Sirojiddin Z. Zainabidinov, Dilshad E. Nazyrov, Valentina P. Usacheva

Scientific Bulletin. Physical and Mathematical Research

The purpose of the present work was a comprehensive study of the diffusion, solubility and electrophysical properties of scandium (Sc), praseodymium (Pr) and europium (Eu) impurities in silicon. On the surface of the KEP-15 a layer of radioactive isotopes was sprayed: 46Sc, 143Pr2O3, or 152Eu2O3. The duration of diffusion annealing varied depending on the diffusion temperature of 5 to 72 hours. Autoradiography, measurements of conductivity and Hall's effect, an isothermal relaxation of capacity and current, a research of diffusion, solubility and electrophysical properties of Sc, Pr and Eu in silicon ...


On Demand Nanoscale Phase Manipulation Of Vanadium Dioxide By Scanning Probe Lithography, Dustin Schrecongost Jan 2020

On Demand Nanoscale Phase Manipulation Of Vanadium Dioxide By Scanning Probe Lithography, Dustin Schrecongost

Graduate Theses, Dissertations, and Problem Reports

This dissertation focuses on nanoscale phase manipulations of Vanadium Dioxide. Nanoscale control of material properties is a current obstacle for the next generation of optoelectronic and photonic devices. Vanadium Dioxide is a strongly correlated material with an insulator-metal phase transition at approximately 345 K that generates dramatic electronic and optical property changes. However, the development of industry device application based on this phenomenon has been limited thus far due to the macroscopic scale and the volatile nature of the phase transition. In this work these limitations are assessed and circumvented.

A home-built, variable temperature, scanning near-field optical microscope was engineered ...


An Instantaneous Normal Mode Description Of Relaxation In Supercooled Liquids, T. Keyes, G. V. Vijayadamodar, Ulrich Zurcher Nov 2019

An Instantaneous Normal Mode Description Of Relaxation In Supercooled Liquids, T. Keyes, G. V. Vijayadamodar, Ulrich Zurcher

Ulrich Zurcher

Relaxation in supercooled liquids is formulated from the instantaneous normal modes (INM) point of view. The frequency and temperature dependence of the unstable, imaginary frequency lobe of the INM density of states, ⟨ρu(ω,T)⟩ (for simplicity we write ω instead of iω), is investigated and characterized over a broad temperature range, 10⩾T⩾0.42, in the unit density Lennard-Jones liquid. INM theories of diffusion invoke Im-ω modes descriptive of barrier crossing, but not all imaginary frequency modes fall into this category. There exists a cutoff frequency ωc such that modes with ω<ωc correspond to “shoulder potentials,” whereas the potential profiles include barrier-crossing double wells for ω>ωc. Given that only modes with ...


A Stochastic Theory Of Inhomogeneously Broadened Linewidths In Solids, Ulrich Zürcher Nov 2019

A Stochastic Theory Of Inhomogeneously Broadened Linewidths In Solids, Ulrich Zürcher

Ulrich Zurcher

We investigate spectral diffusion decay using a model for solids that consists of two-level-systems (TLSs) interacting via strain fields. For the case when the rate of TLS flips vanishes, we find algebraic decay of correlation functions of the local field. We show that properties of equilibrium fluctuations are in agreement with the hierarchical picture proposed by Basché and Moerner: TLSs far away produce fast fluctuations that are small in magnitude, and close TLSs produce large fluctuations that are less frequent.


Polymeric Impulsive Actuation Mechanisms: Development, Characterization, And Modeling, Yongjin Kim Oct 2019

Polymeric Impulsive Actuation Mechanisms: Development, Characterization, And Modeling, Yongjin Kim

Doctoral Dissertations

Recent advances in the field of biomedical and life-sciences are increasingly demanding more life-like actuation with higher degrees of freedom in motion at small scales. Many researchers have developed various solutions to satisfy these emerging requirements. In many cases, new solutions are made possible with the development of novel polymeric actuators. Advances in polymeric actuation not only addressed problems concerning low degree of freedom in motion, large system size, and bio-incompatibility associated with conventional actuators, but also led to the discovery of novel applications, which were previously unattainable with conventional engineered systems.

This dissertation focuses on developing novel actuation mechanisms ...


Probability Density Of The Fractional Langevin Equation With Reflecting Walls, Thomas Vojta, Sarah Skinner, Ralf Metzler Oct 2019

Probability Density Of The Fractional Langevin Equation With Reflecting Walls, Thomas Vojta, Sarah Skinner, Ralf Metzler

Physics Faculty Research & Creative Works

We investigate anomalous diffusion processes governed by the fractional Langevin equation and confined to a finite or semi-infinite interval by reflecting potential barriers. As the random and damping forces in the fractional Langevin equation fulfill the appropriate fluctuation-dissipation relation, the probability density on a finite interval converges for long times towards the expected uniform distribution prescribed by thermal equilibrium. In contrast, on a semi-infinite interval with a reflecting wall at the origin, the probability density shows pronounced deviations from the Gaussian behavior observed for normal diffusion. If the correlations of the random force are persistent (positive), particles accumulate at the ...


Quantifying Complex Systems Via Computational Fly Swarms, Troy Taylor May 2019

Quantifying Complex Systems Via Computational Fly Swarms, Troy Taylor

Senior Theses

Complexity is prevalent both in natural and in human-made systems, yet is not well understood quantitatively. Qualitatively, complexity describes a phenomena in which a system composed of individual pieces, each having simple interactions with one another, results in interesting bulk properties that would otherwise not exist. One example of a complex biological system is the bird flock, in particular, a starling murmuration. Starlings are known to move in the direction of their neighbors and avoid collisions with fellow starlings, but as a result of these simple movement choices, the flock as a whole tends to exhibit fluid-like movements and form ...


Viscosities, Diffusion Coefficients, And Mixing Times Of Intrinsic Fluorescent Organic Molecules In Brown Limonene Secondary Organic Aerosol And Tests Of The Stokes–Einstein Equation, Dagny A. Ullmann, Mallory L. Hinks, Adrian M. Maclean, Christopher Butenhoff, James W. Grayson, Kelley Barsanti, Jose L. Jimenez, Sergey A. Nizkorodov, Saeid Kamal, Allan K. Bertram Feb 2019

Viscosities, Diffusion Coefficients, And Mixing Times Of Intrinsic Fluorescent Organic Molecules In Brown Limonene Secondary Organic Aerosol And Tests Of The Stokes–Einstein Equation, Dagny A. Ullmann, Mallory L. Hinks, Adrian M. Maclean, Christopher Butenhoff, James W. Grayson, Kelley Barsanti, Jose L. Jimenez, Sergey A. Nizkorodov, Saeid Kamal, Allan K. Bertram

Physics Faculty Publications and Presentations

Viscosities and diffusion rates of organics within secondary organic aerosol (SOA) remain uncertain. Using the bead-mobility technique, we measured viscosities as a function of water activity (aw) of SOA generated by the ozonolysis of limonene followed by browning by exposure to NH3 (referred to as brown limonene SOA or brown LSOA). These measurements together with viscosity measurements reported in the literature show that the viscosity of brown LSOA increases by 3–5 orders of magnitude as the aw decreases from 0.9 to approximately 0.05. In addition, we measured diffusion coefficients of intrinsic fluorescent organic molecules within ...


Pore Diameter Dependence Of Catalytic Activity: P-Nitrobenzaldehyde Conversion To An Aldol Product In Amine-Functionalized Mesoporous Silica, Andres Garcia, Igor I. Slowing, James W. Evans Jul 2018

Pore Diameter Dependence Of Catalytic Activity: P-Nitrobenzaldehyde Conversion To An Aldol Product In Amine-Functionalized Mesoporous Silica, Andres Garcia, Igor I. Slowing, James W. Evans

Chemistry Publications

The reaction yield for conversion of p-nitrobenzaldehyde (PNB) to an aldol product in amine-functionalized mesoporous silica nanoparticles (MSN) exhibits a 20-fold enhancement for a modest increase in pore diameter, d. This enhanced catalytic activity is shown to reflect a strong increase in the “passing propensity,” 𝒫, of reactant and product species inside the pores. We find that 𝒫 ≈ 0, corresponding to single-file diffusion, applies for the smallest d which still significantly exceeds the linear dimensions of PNB and the aldol product. However, in this regime of narrow pores, these elongated species must align with each other and with the pore ...


Imaging The Three-Dimensional Orientation And Rotational Mobility Of Fluorescent Emitters Using The Tri-Spot Point Spread Function, Oumeng Zhang, Jin Lu, Tianben Ding, Matthew D. Lew Jun 2018

Imaging The Three-Dimensional Orientation And Rotational Mobility Of Fluorescent Emitters Using The Tri-Spot Point Spread Function, Oumeng Zhang, Jin Lu, Tianben Ding, Matthew D. Lew

Electrical & Systems Engineering Publications and Presentations

Fluorescence photons emitted by single molecules contain rich information regarding their rotational motions, but adapting single-molecule localization microscopy (SMLM) to measure their orientations and rotational mobilities with high precision remains a challenge. Inspired by dipole radiation patterns, we design and implement a Tri-spot point spread function (PSF) that simultaneously measures the three-dimensional orientation and the rotational mobility of dipole-like emitters across a large field of view. We show that the orientation measurements done using the Tri-spot PSF are sufficiently accurate to correct the anisotropy-based localization bias, from 30 nm to 7 nm, in SMLM. We further characterize the emission anisotropy ...


Physical Lens On The Cell: Advanced Diffusion And The Fokker-Planck Picture, Daniel M. Zuckerman Jun 2018

Physical Lens On The Cell: Advanced Diffusion And The Fokker-Planck Picture, Daniel M. Zuckerman

Scholar Archive

On the one hand, the basics of diffusion seem easy to understand: random motion, a Gaussian distribution of steps, and linear (in time) mean-squared distance behavior. On the other hand, the diffusion equation is a partial differential equation ... and it only describes simple diffusion, whereas observed diffusion in cells is rarely simple and requires still more complicated math. Here you can deepen your understanding of the math and physics underlying diffusive behavior.


The Computational Study Of Fly Swarms & Complexity, Austin Bebee May 2018

The Computational Study Of Fly Swarms & Complexity, Austin Bebee

Senior Theses

A system is considered complex if it is composed of individual parts that abide by their own set of rules, while the system, as a whole, will produce non-deterministic properties. This prevents the behavior of such systems from being accurately predicted. The motivation for studying complexity spurs from the fact that it is a fundamental aspect of innumerable systems. Among complex systems, fly swarms are relatively simple, but even so they are still not well understood. In this research, several computational models were developed to assist with the understanding of fly swarms. These models were primarily analyzed by using the ...


The Advection-Diffusion Equation And The Enhanced Dissipation Effect For Flows Generated By Hamiltonians, Michael Kumaresan May 2018

The Advection-Diffusion Equation And The Enhanced Dissipation Effect For Flows Generated By Hamiltonians, Michael Kumaresan

Dissertations, Theses, and Capstone Projects

We study the Cauchy problem for the advection-diffusion equation when the diffusive parameter is vanishingly small. We consider two cases - when the underlying flow is a shear flow, and when the underlying flow is generated by a Hamiltonian. For the former, we examine the problem on a bounded domain in two spatial variables with Dirichlet boundary conditions. After quantizing the system via the Fourier transform in the first spatial variable, we establish the enhanced-dissipation effect for each mode. For the latter, we allow for non-degenerate critical points and represent the orbits by points on a Reeb graph, with vertices representing ...


Fractional Brownian Motion With A Reflecting Wall, Alexander H. O. Wada, Thomas Vojta Feb 2018

Fractional Brownian Motion With A Reflecting Wall, Alexander H. O. Wada, Thomas Vojta

Physics Faculty Research & Creative Works

Fractional Brownian motion, a stochastic process with long-time correlations between its increments, is a prototypical model for anomalous diffusion. We analyze fractional Brownian motion in the presence of a reflecting wall by means of Monte Carlo simulations. Whereas the mean-square displacement of the particle shows the expected anomalous diffusion behavior (x2) ~ tα, the interplay between the geometric confinement and the long-time memory leads to a highly non-Gaussian probability density function with a power-law singularity at the barrier. In the superdiffusive case α > 1, the particles accumulate at the barrier leading to a divergence of the probability density. For ...


Investigation Of Iron Oxide Nanocolloidal Suspension Diffusion Using A Direct Imaging Method, Ashley E. Rice, Ana Oprisan Nov 2017

Investigation Of Iron Oxide Nanocolloidal Suspension Diffusion Using A Direct Imaging Method, Ashley E. Rice, Ana Oprisan

Journal of the South Carolina Academy of Science

We performed a set of experiments using a direct imaging method to investigate the diffusion process of iron oxide, Fe2O3, nanoparticles. We studied concentration fluctuations that move against the concentration gradient and induce disturbances in the interface between the iron oxide suspension and water in the sample cell. Using this imaging method in combination with the differential dynamic algorithm for image processing, we are able to extract information about the power, size, and lifetime of the fluctuations. We performed this experiment both in the presence and in the absence of a 4.2 mT magnetic field. We ...


Analysis Of Residence Time In The Measurement Of Radon Activity By Passive Diffusion In An Open Volume: A Micro-Statistical Approach, Mark P. Silverman Aug 2017

Analysis Of Residence Time In The Measurement Of Radon Activity By Passive Diffusion In An Open Volume: A Micro-Statistical Approach, Mark P. Silverman

Faculty Scholarship

Residence time in a flow measurement of radioactivity is the time spent by a pre-determined quantity of radioactive sample in the flow cell. In a recent report of the measurement of indoor radon by passive diffusion in an open volume (i.e. no flow cell or control volume), the concept of residence time was generalized to apply to measurement conditions with random, rather than directed, flow. The generalization, leading to a quantity r ∆t , involved use of a) a phenomenological alpha-particle range function to calculate the effective detection volume, and b) a phenomenological description of diffusion by Fick’s law ...


Application Of The Fokker-Planck Molecular Mixing Model To Turbulent Scalar Mixing Using Moment Methods, Ehsan Madadi-Kandjani, Rodney O. Fox, Alberto Passalacqua Jun 2017

Application Of The Fokker-Planck Molecular Mixing Model To Turbulent Scalar Mixing Using Moment Methods, Ehsan Madadi-Kandjani, Rodney O. Fox, Alberto Passalacqua

Chemical and Biological Engineering Publications

An extended quadrature method of moments using the beta kernel density function (beta-EQMOM) is used to approximate solutions to the evolution equation for univariate and bivariate composition probability distribution functions (PDFs) of a passive scalar for binary and ternary mixing. The key element of interest is the molecular mixing term, which is described using the Fokker-Planck (FP) molecular mixing model. The direct numerical simulations (DNSs) of Eswaran and Pope ["Direct numerical simulations of the turbulent mixing of a passive scalar,"Phys. Fluids 31, 506 (1988)] and the amplitude mapping closure (AMC) of Pope ["Mapping closures for turbulent mixing and reaction ...


Stochastic Modeling Of Catalytic Processes In Nanoporous Materials: Beyond Mean-Field Approach, Andres Garcia Jan 2017

Stochastic Modeling Of Catalytic Processes In Nanoporous Materials: Beyond Mean-Field Approach, Andres Garcia

Graduate Theses and Dissertations

Transport and reaction in zeolites and other porous materials, such as mesoporous silica particles, has been a focus of interest in recent years. This is in part due to the possibility of anomalous transport effect (e.g. single-file diffusion) and its impact in the reaction yield in catalytic processes. Computational simulations are often used to study these complex non-equilibrium systems. Computer simulations using Molecular Dynamics (MD) techniques are prohibitive, so instead coarse grained one-dimensional models with the aid of Kinetic Monte Carlo (KMC) simulations are used. Both techniques can be computationally expensive, both time and resource wise. These coarse-grained systems ...


Using Underground Radon To Detect Inactive Geological Faults, Germán Rodríguez Ortiz Jan 2017

Using Underground Radon To Detect Inactive Geological Faults, Germán Rodríguez Ortiz

Open Access Theses & Dissertations

This Thesis presents the results of an investigation of the concentration of radon in soil around a fault in the East Franklin Mountains in the El Paso area in West Texas. The connection between underground radon exhalations near active faults has been known for decades, but possible similar increases of underground radon levels around inactive faults have not been studied as thoroughly. Arguing that the dilatancy-diffusion model used to explain the phenomenon near active faults does not apply to the case of inactive faults, a hypoThesis is formulated under which increased levels of underground radon must be present near inactive ...


Nanostructure Control: Nucleation And Diffusion Studies For Predictable Ultra Thin Film Morphologies, Matthew Hershberger Jan 2017

Nanostructure Control: Nucleation And Diffusion Studies For Predictable Ultra Thin Film Morphologies, Matthew Hershberger

Graduate Theses and Dissertations

This thesis covers PhD research on two systems with unique and interesting physics. The first system is lead (Pb) deposited on the silicon (111) surface with the 7x7 reconstruction. Pb and Si are mutually bulk insolubility resulting in this system being an ideal case for studying metal and semiconductor interactions. Initial Pb deposition causes an amorphous wetting layer to form across to surface. Continued deposition results in Pb(111) island growth. Classic literature has classified this system as the Stranski-Krastanov growth mode although the system is not near equilibrium conditions. Our research shows a growth mode distinctly different than classical ...


Towards A Prediction Of Landscape Evolution From Chemical Weathering And Soil Production, Eric Alan Jackson Jan 2017

Towards A Prediction Of Landscape Evolution From Chemical Weathering And Soil Production, Eric Alan Jackson

Browse all Theses and Dissertations

The time evolution of a periodic landscape under the influence of chemical weathering and physical erosion is computed. The model used incorporates weathering and soil production as a flux limited reaction controlled by groundwater flow. Scaling of the flow rate is obtained from a percolation theoretic treatment. The erosion of the soil material produced by this process is modeled by the diffusion of elevation, as consistent with downslope soil transport proportional to the tangent of the angle of the topography, and application of the equation of continuity to surface soil transport. Three initial topographies are examined over a periods of ...


Single Particle Tracking: Analysis Techniques For Live Cell Nanoscopy., Peter K. Relich Dec 2016

Single Particle Tracking: Analysis Techniques For Live Cell Nanoscopy., Peter K. Relich

Physics & Astronomy ETDs

Single molecule experiments are a set of experiments designed specifically to study the properties of individual molecules. It has only been in the last three decades where single molecule experiments have been applied to the life sciences; where they have been successfully implemented in systems biology for probing the behaviors of sub-cellular mechanisms. The advent and growth of super-resolution techniques in single molecule experiments has made the fundamental behaviors of light and the associated nano-probes a necessary concern among life scientists wishing to advance the state of human knowledge in biology. This dissertation disseminates some of the practices learned in ...


Point Island Models For Nucleation And Growth Of Supported Nanoclusters During Surface Deposition, Yong Han, Émilie Gaudry, Tiago J. Oliveira, James W. Evans Dec 2016

Point Island Models For Nucleation And Growth Of Supported Nanoclusters During Surface Deposition, Yong Han, Émilie Gaudry, Tiago J. Oliveira, James W. Evans

Physics and Astronomy Publications

Point island models (PIMs) are presented for the formation of supported nanoclusters (or islands) during deposition on flat crystalline substrates at lower submonolayer coverages. These models treat islands as occupying a single adsorption site, although carrying a label to track their size (i.e., they suppress island structure). However, they are particularly effective in describing the island size and spatial distributions. In fact, these PIMs provide fundamental insight into the key features for homogeneous nucleation and growth processes on surfaces. PIMs are also versatile being readily adapted to treat both diffusion-limited and attachment-limited growth and also a variety of other ...


Catalytic Conversion In Nanoporous Materials: Concentration Oscillations And Spatial Correlations Due To Inhibited Transport And Intermolecular Interactions, Andrés García, James W. Evans Nov 2016

Catalytic Conversion In Nanoporous Materials: Concentration Oscillations And Spatial Correlations Due To Inhibited Transport And Intermolecular Interactions, Andrés García, James W. Evans

Physics and Astronomy Publications

We show that steady-state catalytic conversion in nanoporous materials can occur in a quasi-counter-diffusion mode with the reactant (product) concentration strongly decaying (growing) into the pore, but also with oscillations in the total concentration. These oscillations reflect the response of the fluid to the transition from an extended to a confined environment near the pore opening. We focus on the regime of strongly inhibited transport in narrow pores corresponding to single-file diffusion. Here, limited penetration of the reactant into the pores and the associated low reaction yield is impacted by strong spatial correlations induced by both reaction (non-equilibrium correlations) and ...


Method To Measure Indoor Radon Concentration In An Open Volume With Geiger-Mueller Counters: Analysis From First Principles, Mark P. Silverman Oct 2016

Method To Measure Indoor Radon Concentration In An Open Volume With Geiger-Mueller Counters: Analysis From First Principles, Mark P. Silverman

Faculty Scholarship

A simple method employing a pair of pancake-style Geiger-Mueller (GM) counters for quantitative measurement of radon activity concentration (activity per unit volume) is described and demonstrated. The use of two GM counters, together with the basic theory derived in this paper, permit the detection of alpha particles from decay of 222Rn and progeny ( 218 Po , 214 Po ) and the conversion of the alpha count rate into a radon concentration. A unique feature of this method, in comparison with standard methodologies to measure radon concentration, is the absence of a fixed control volume. Advantages afforded by the reported GM method include ...


Method To Measure Indoor Radon Concentration In An Open Volume With Geiger-Mueller Counters: Analysis From First Principles, Mark P. Silverman Oct 2016

Method To Measure Indoor Radon Concentration In An Open Volume With Geiger-Mueller Counters: Analysis From First Principles, Mark P. Silverman

Faculty Scholarship

A simple method employing a pair of pancake-style Geiger-Mueller (GM) counters for quantitative measurement of radon activity concentration (activity per unit volume) is described and demonstrated. The use of two GM counters, together with the basic theory derived in this paper, permit the detection of alpha particles from decay of 222Rn and progeny ( 218Po , 214 Po ) and the conversion of the alpha count rate into a radon concentration. A unique feature of this method, in comparison with standard methodologies to measure radon concentration, is the absence of a fixed control volume. Advantages afforded by the reported GM method include: 1 ...


Classical Transport In Disordered Systems, Antonios Papaioannou Jun 2016

Classical Transport In Disordered Systems, Antonios Papaioannou

Dissertations, Theses, and Capstone Projects

This thesis reports on the manifestation of structural disorder on molecular transport and it consists of two parts. Part I discusses the relations between classical transport and the underlying structural complexity of the system. Both types of molecular diffusion, namely Gaussian and non-Gaussian are presented and the relevant time regimes are discussed. In addition the concept of structural universality is introduced and connected with the diffusion metrics. One of the most robust techniques for measuring molecular mean square displacements is magnetic resonance. This method requires encoding and subsequently reading out after an experimentally controlled time, a phase ϕ to the ...


Tunable Controlled Release Of Molecular Species From Halloysite Nanotubes, Divya Narayan Elumalai Apr 2016

Tunable Controlled Release Of Molecular Species From Halloysite Nanotubes, Divya Narayan Elumalai

Doctoral Dissertations

Encouraged by potential applications in rust coatings, self-healing composites, selective delivery of drugs, and catalysis, the transport of molecular species through Halloysite nanotubes (HNTs), specifically the storage and controlled release of these molecules, has attracted strong interest in recent years. HNTs are a naturally occurring biocompatible nanomaterial that are abundantly and readily available. They are alumosilicate based tubular clay nanotubes with an inner lumen of 15 nm and a length of 600-900 nm. The size of the inner lumen of HNTs may be adjusted by etching. The lumen can be loaded with functional agents like antioxidants, anticorrosion agents, flame-retardant agents ...


Excitonic Processes, Energy Transport, And Excited States In Organic Materials, Vincent Sean Zoutenbier Jan 2016

Excitonic Processes, Energy Transport, And Excited States In Organic Materials, Vincent Sean Zoutenbier

Theses and Dissertations

This dissertation has roots in the distinctly human endeavor to harness energy. We study singlet exciton fission, which has the remarkable ability to double the number of energy carriers (excitons) through singlet fission, and its reverse process triplet fusion, which can combine triplet excitons. Understanding the fundamental mechanisms that enable singlet fission may allow for it to be engineered for use with other materials for solar cell applications.We experimentally investigate the creation of singlet and triplet excitons in rubrene single crystals, how one species can convert into the other by excitonic fission and fusion processes, and how triplet excitons ...


Understanding Electrical Conduction In Lithium Ion Batteries Through Multi-Scale Modeling, Jie Pan Jan 2016

Understanding Electrical Conduction In Lithium Ion Batteries Through Multi-Scale Modeling, Jie Pan

Theses and Dissertations--Chemical and Materials Engineering

Silicon (Si) has been considered as a promising negative electrode material for lithium ion batteries (LIBs) because of its high theoretical capacity, low discharge voltage, and low cost. However, the utilization of Si electrode has been hampered by problems such as slow ionic transport, large stress/strain generation, and unstable solid electrolyte interphase (SEI). These problems severely influence the performance and cycle life of Si electrodes. In general, ionic conduction determines the rate performance of the electrode, while electron leakage through the SEI causes electrolyte decomposition and, thus, causes capacity loss. The goal of this thesis research is to design ...