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Filtering by: Alternative title ssim Circular of information no. 385 Remove constraint Alternative title ssim: Circular of information no. 385 Committee Member Jansen, Henri Remove constraint Committee Member: Jansen, Henri Degree Name Doctor of Philosophy (Ph.D.) Remove constraint Degree Name: Doctor of Philosophy (Ph.D.)

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  • Simultaneous beta/gamma digital spectroscopy

    Creator:
    Farsoni, Abdollah T.
    Abstract:
    A state-of-the-art radiation detection system for simultaneous spectroscopy of beta-particles and gamma-rays has been developed. The system utilizes a triplelayer phoswich detector and a customized Digital Pulse Processor (DPP) built in our laboratory. The DPP board was designed to digitally capture the analog signal pulses and, following several digital preprocessing...
    Resource Type:
    Dissertation
    Full Text:
    absorption and the loss of spectroscopic information necessary for reconstructing a useful beta spectrum

  • Physical processes that control droplet transport in rock fracture systems

    Creator:
    Hay, Katrina M.
    Abstract:
    Aquifer recharge is generally driven by fluids that move from the Earth’s surface to groundwater through the unsaturated zone, also known as the vadose zone. When the vadose zone is fractured, fluids, which may include contaminants, can move through the fracture network as well as the porous matrix. Such a...
    Resource Type:
    Dissertation
    Full Text:
    , the fluid adjacent to a solid cannot move (no-slip boundary condition). The motion of the fluid as it

  • Sub-diffraction light propagation and imaging in planar negative refraction waveguides

    Creator:
    Wangberg, Robyn
    Abstract:
    In this dissertation we study the electromagnetic properties of planar waveguides with non-magnetic strongly anisotropic dielectric cores. We develop an analytical description of the mode propagation in these systems and show that the index of refraction can be either positive or negative depending on the specific material parameters. Propagating modes...
    Resource Type:
    Dissertation
    Full Text:
    . 43924-G10), National Science Foundation (Grant No. ECCS- 0724763), Office of Naval Research (Grant No

  • Electromagnetic properties of anisotropic plasmonic metamaterials

    Creator:
    Elser, Justin Lee
    Abstract:
    In this dissertation we study the electromagnetic properties of plasmonic metamaterials. We develop an analytical description to solve the fundamental problem of free-space scattering in planar plasmonic systems by utilizing anisotropic metamaterials. We show with exact numerical simulations that these manufactured materials do completely eliminate the scattering, and even in...
    Resource Type:
    Dissertation
    Full Text:
    refraction is changed and no extraneous modes are excited. . . . . . . . . . 38 3.1 The evolution of coupled

  • Computational nanooptics in hyperbolic metamaterials and plasmonic structures

    Creator:
    Thongrattanasiri, Sukosin
    Abstract:
    This dissertation concerns several problems in the fields of light interaction with nanostructured media, metamaterials, and plasmonics. We present a technique capable of extending operational bandwidth of hyperbolic metamaterials based on interleaved highly-doped InGaAs and undoped AlInAs multilayer stacks. The experimental results confirm theoretical predictions, exhibiting broadband negative refraction response...
    Resource Type:
    Dissertation
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    convert subwavelength information of objects into propagating waves and project this information into

  • Submerged jet impingement boiling thermal management

    Creator:
    Cardenas, Ruander
    Abstract:
    Technologies such as avionics and power electronics are driving the demand for thermal management schemes towards high heat fluxes and low surface temperatures. Typically, these applications require the dissipation of heat fluxes in the rage of 100-1000 W/cm² while maintaining surface temperatures lower than about 85 °C. Phase-change heat transfer...
    Resource Type:
    Dissertation
    Full Text:
    of geometrical and flow parameters on heat transfer performance are examined for a single circular

  • An Ising-like model to predict dielectric properties of the relaxor ferroelectric solid solution BaTiO3 - Bi(Zn1/2Ti1/2)O3, An Ising-like model to predict dielectric properties of the relaxor ferroelectric solid solution BaTiO₃ − Bi(Zn₁/₂Ti₁/₂)O₃

    Creator:
    Jackson, Dennis L.
    Abstract:
    We developed a model to investigate the dielectric properties of the BaTiO₃ − Bi(Zn₁/₂Ti₁/₂)O₃ (BT-BZT) solid solution, which is a relaxor ferroelectric and exhibits long range disorder. The model uses ab initio methods to determine all polarization states for every atomic configuration of 2 x 2 x 2 supercells of...
    Resource Type:
    Dissertation
    Full Text:
    AN ABSTRACT OF THE DISSERTATION OF Dennis L. Jackson for the

  • Level structure of ¹⁵²Gd populated in ¹⁵²Tb β decay

    Creator:
    Stapels, Christopher John
    Abstract:
    As part of a research program to study the transitional region of N=88 isotones, ¹⁵²Tb was produced by the reaction ¹⁵¹Eu(α,3n)¹⁵²Tb in the 88" cyclotron located at LBNL. Gamma-ray spectroscopy of the radiation emitted from excited ¹⁵²Gd following the β⁺ decay of ¹⁵²Tb has been performed using an array of...
    Resource Type:
    Dissertation
    Full Text:
    amount of information from the radiation, it is necessary to understand the nature of the radiation

  • A theoretical description of anisotropic chemical association and its application to hydrogen-bonded fluids

    Creator:
    Peery, Travis B.
    Abstract:
    The thermodynamic and structural effects of highly anisotropic, short-ranged attraction are investigated for single- and four-site interaction models using Wertheim's multi-density graph theory of chemical association. Both models consist of associating hard spheres, where the saturable attraction sites are described by conical wells centered in the hard core and evaluated...
    Resource Type:
    Dissertation
    Full Text:
    van der Waals theory contains no information about the nature of intermolecular forces, being instead

  • A moving boundary model of calcium alginate gel formation and the estimation of diffusion and mass transfer coefficients

    Creator:
    Inoue, Shawna K.
    Abstract:
    Calcium alginate gels are widely used in the biotechnology, food, and pharmaceutical industries for cell immobilization, food additives, and controlling the release of therapeutic agents. Different gelation conditions can lead to different gel structures which affects the diffusion of solutes in gels, thus mathematical models were developed to describe diffusion...
    Resource Type:
    Dissertation
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    basic information on alginate, as well as a summary of its properties, uses, and role in forming