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Showing 1 to 16 of 16 for “"electron diffusion"”.
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Structure of the electron diffusion region in magnetic reconnection with small guide fields
… of magnetic reconnection have shown high electron pressure anisotropy in the inflow of electron diffusion regions. This anisotropy has been accurately accounted for in a new fluid closure for collisionless reconnection. By tracing electron orbits in the fields taken from particle-in-cell …
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Relationships between electron transport and redox center concentrations within molecular networks
A microscopic model was developed to describe electron diffusion among redox centers in a rigid network. The model describes electron diffusion coefficients, $D\sb E$, that are based on a random walk, and includes a hard-sphere approximation for the redox molecules, the electronic structure of …
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Development and Application of Stochastic Methods for Radiation Belt Simulations
… describes a method for modeling radiation belt electron diffusion, which solves the radiation belt Fokker-Planck equation using its equivalent stochastic differential equations, and presents applications of this method to investigating drift shell splitting effects on radiation belt electron …
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Transient and steady state electrochemical studies of transport dynamics and equilibria in thin polymer films containing redox centers
Electron transport dynamics and equilibrium effects were studied for the ferricyanide/ferrocyanide (Fe(CN)$\sb6\sp{3-/4-}$) redox couple incorporated in partially-quaternized poly(4-vinylpyridine) (QPVP) modified electrodes in contact with potassium nitrate (KNO$\sb3$) solution. The goal was to …
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Two-fluid simulations of magnetic reconnection with a kinetic closure for the electron pressure anisotropy
… dynamics, it depends intimately on small-scale electron physics. In weakly-collisional plasmas, electron pressure anisotropy resulting from the electric and magnetic trapping of electrons strongly affects the structure surrounding the electron diffusion region and the electron current layer. …
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Zero-field time-of-flight characterization of minority carrier transport in heavily carbon-doped gallium arsenide and indium gallium arsenide
… p-type GaAs is important for both optical and electronic devices, and recently carbon has become the preferred base dopant for AlGaAs/GaAs and InGaP/GaAs heterojunction bipolar transistors (HBTs) due to its high solubility and low diffusivity in GaAs. The low diffusivity of carbon, relative to …
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Investigation of dye-sensitized solar cell performance with single chirality semiconducting carbon nanotubes
… (CNTs) allow a selection of band-gap and electron mobility. Separating a specific chirality from a mixture of carbon nanotubes remains challenging task. Among separation techniques, one of the most promising is size-exclusion gel chromatography. Although SWNTs separated by this technique …
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"Smoking-Gun" Observables of Magnetic Reconnection: Spatiotemporal Evolution of Electron Characteristics Throughout the Diffusion Region
… happen in a collisionless plasma? Knowledge of electron-scale dynamics is necessary to answer this outstanding question of plasma physics. Based on fully kinetic particle-in-cell (PIC) simulations of symmetric reconnection, the spatiotemporal evolution of velocity distribution functions in and …
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Investigation of layer-by-layer assembly and M13 bacteriophage nanowires for dye-sensitized solar cells
… with a novel nanowire architecture to enhance electron transport. The biotemplated nanowires are shown to significantly increase device electron diffusion length and increase device efficiency as compared to LbL-templated titania photoanodes made without bacteriophage. Spray LbL is also …
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Investigating the Electron Transport and Light Scattering Enhancement in Radial Core-Shell Metal-Metal Oxide Novel 3D Nanoarchitectures for Dye Sensitized Solar Cells
… cost alternative to silicon based solar cells. Electron transport is one of the prominent processes in the cell and it is further a complex process because the transport medium is a mesoporous film. The gaps in the pores are completely filled by an electrolyte with high ionic strength, resulting …
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Characterization and simulation of three-dimensional solid-state solar cells
… of the final performance of a 3D-cell. Diffusion models : Detailed effective medium models are set-up which describe both steady-state and dynamic response of the cells. In one of the models, the cell is treated as an infinite network of flat band unit cells (i.e. there is no electric …
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Small-scale fluctuations in D-region ionization due to hydrodynamic turbulence
… prediction of observed scattered power from electron-concentration fluctuations. The electron-neutral and ion-neutral collision frequencies for usc in the continuum momentum equation are determined for low-frequency phenomena in the lower ionosphere. It is found that the assumption of a …
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Lower Hybrid Current Drive on Alcator C-Mod : measurements with an upgraded MSE diagnostic and comparisons to simulation
… adding experimentally-constrained levels of fast-electron diffusion do not reconcile profile discrepancies. Some qualitative profile trends in single parameter scans are reproduced by the simulations including broadening of profiles at higher current, and a weak dependence on the launched …
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Investigation of Charge Transfer in Metal-Organic Frameworks for Electrochemical Applications
… happen through redox hopping, i.e. site-to-site electron hopping coupled to diffusion of counter ions to balance electroneutrality. While the apparent diffusion coefficient (Dapp) has been employed to describe the overall charge transfer efficiency, independent elucidation of electron and ion …
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Modeling of Outer Radiation Belt Electron Scattering due to Spatial and Spectral Properties of ULF Waves
… interactions for relativistic (0.5-10 MeV) electrons in Earth's outer radiation belt (r = 3-7 RE, or L-shells: L = 3-7) interacting with magnetospheric Pc-5 (ULF) waves. This dissertation focuses on ideal models for short and long term electron energy and radial position scattering caused by …
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Synthesis and microstructural characterization of phosphate cathode materials prepared by a polymeric steric entrapment precursor route
… appealing for applications that include portable electronics such as cellular phones and laptop computers. However, larger scale Li-ion battery system for vehicles and grid load leveling as well as complementary energy storage for renewable energy resources, such as solar and wind power seems to …