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Full-Text Articles in Physical Sciences and Mathematics

The Primary Source Of Environmental Concern: New Environmental Paradigm Or Presumed Vested Interest Based On Area Of Residence?, Scott Christopher Ramsey Jan 1995

The Primary Source Of Environmental Concern: New Environmental Paradigm Or Presumed Vested Interest Based On Area Of Residence?, Scott Christopher Ramsey

Dissertations, Theses, and Masters Projects

No abstract provided.


Occurrence, Fate And Effects Of Polychlorinated Terphenyls In An Estuarine Environment, Kathryn Gallagher Jan 1995

Occurrence, Fate And Effects Of Polychlorinated Terphenyls In An Estuarine Environment, Kathryn Gallagher

Dissertations, Theses, and Masters Projects

Aroclor 5432, a mixture of polychlorinated terphenyls (PCT), was detected in sediment and several biological compartments including: saltmarsh cordgrass (Spartina alterniflora), American oysters (Crassostrea virginica), red-jointed fiddler crabs (Uca minax), wharf crabs (Sesarma reticulatum) and mummichogs (Fundulus heteroclitus) collected from Tabbs Creek. This tidal creek is located in the southern Chesapeake Bay region. Species from several phyla were selected in order to examine PCT accumulation in physiologically and ecologically different organisms. In general, PCT concentrations in sediment and biota decreased with distance downstream from the PCT outfall. The organism with the highest mean concentration (18,300 &\mu&g/kg dry weight) was the …


Beam Dynamics In The Cebaf Superconducting Cavities, Zenghai Li Jan 1995

Beam Dynamics In The Cebaf Superconducting Cavities, Zenghai Li

Dissertations, Theses, and Masters Projects

This work is a study of beam dynamics in the CEBAF superconducting cavities under the influence of the fields generated by externally applied RF and beam particles.;A full 3-D modeling of the CEBAF 5-cell superconducting cavity is carried out. Details of the modeling with MAFIA are discussed. Multipole fields due to the asymmetric couplers are studied by means of 3-D Fourier transforms. The cavity steering and focusing of the multipole fields are studied. Experimental measurements of these effects are performed to validate the modeling. Evaluation of the cavity misalignment is discussed. The emittance degradation effects in the CEBAF superconducting linacs …


A Comparison Of Three Wetland Evaluation Methods In Their Assessment Of Nontidal Wetlands In The Coastal Plain Of Virginia, Melissa Claire Chaun Jan 1995

A Comparison Of Three Wetland Evaluation Methods In Their Assessment Of Nontidal Wetlands In The Coastal Plain Of Virginia, Melissa Claire Chaun

Dissertations, Theses, and Masters Projects

No abstract provided.


Blends Of Reactive Diluents With Phenylethynyl-Terminated Arylene Ether Oligomers, Rachel Louise Knudsen Jan 1995

Blends Of Reactive Diluents With Phenylethynyl-Terminated Arylene Ether Oligomers, Rachel Louise Knudsen

Dissertations, Theses, and Masters Projects

No abstract provided.


Immigration Variability And Post-Settlement Processes Of The Spiny Lobster, Panulirus Argus, In The Exuma Cays, Bahamas, Luis Coba-Cetina Jan 1995

Immigration Variability And Post-Settlement Processes Of The Spiny Lobster, Panulirus Argus, In The Exuma Cays, Bahamas, Luis Coba-Cetina

Dissertations, Theses, and Masters Projects

No abstract provided.


Metallization Of Polyimide Films To Enhance Dimensional Stability And To Achieve Reflective And Conductive Surfaces, David Scott Thompson Jan 1995

Metallization Of Polyimide Films To Enhance Dimensional Stability And To Achieve Reflective And Conductive Surfaces, David Scott Thompson

Dissertations, Theses, and Masters Projects

No abstract provided.


Constrained Least-Squares Digital Image Restoration, Rajeeb Hazra Jan 1995

Constrained Least-Squares Digital Image Restoration, Rajeeb Hazra

Dissertations, Theses, and Masters Projects

The design of a digital image restoration filter must address four concerns: the completeness of the underlying imaging system model, the validity of the restoration metric used to derive the filter, the computational efficiency of the algorithm for computing the filter values and the ability to apply the filter in the spatial domain. Consistent with these four concerns, this dissertation presents a constrained least-squares (CLS) restoration filter for digital image restoration. The CLS restoration filter is based on a comprehensive, continuous-input/discrete- processing/continuous-output (c/d/c) imaging system model that accounts for acquisition blur, spatial sampling, additive noise and imperfect image reconstruction. The …


Spawning And Ecology Of Early Life Stages Of Black Drum, Pogonias Cormis, In Lower Chesapeake Bay, Louis Broaddus Daniel Iii Jan 1995

Spawning And Ecology Of Early Life Stages Of Black Drum, Pogonias Cormis, In Lower Chesapeake Bay, Louis Broaddus Daniel Iii

Dissertations, Theses, and Masters Projects

During spring 1990 and 1991, ichthyoplankton surveys were conducted in lower Chesapeake Bay to estimate seasonal egg production, population biomass and the impact of predation by gelatinous zooplankton on early life stages of black drum, Pogonias cromis. Rearing experiments indicated that at least three species of sciaenid (silver perch, Bairdiella chrysoura; weakfish, Cynoscion regalis and P. cromis) were spawning in the survey area during both years. Specific identification of eggs based on previously published ranges of outside egg diameter (OED) were not reliable due to considerable overlap in diameter distributions. Analysis of weekly OED frequency revealed the presence of three …


Filtration Of Oysters In Patches: Effects Of Water Flow And Seston Composition, Deborah Armitage Harsh Jan 1995

Filtration Of Oysters In Patches: Effects Of Water Flow And Seston Composition, Deborah Armitage Harsh

Dissertations, Theses, and Masters Projects

No abstract provided.


Osmotic Tolerance And Volume Regulation In Cultured Cells Of The Oyster Pathogen Perkinsus Marinus, Caroline L. O'Farrell Jan 1995

Osmotic Tolerance And Volume Regulation In Cultured Cells Of The Oyster Pathogen Perkinsus Marinus, Caroline L. O'Farrell

Dissertations, Theses, and Masters Projects

No abstract provided.


Wave Diffraction And Refraction Problem And A Block-Wise Band Matrix Solver, Changqing Li Jan 1995

Wave Diffraction And Refraction Problem And A Block-Wise Band Matrix Solver, Changqing Li

Dissertations, Theses, and Masters Projects

No abstract provided.


Continuous Electron Stimulated Oxygen Atom Emission From Ag Permeation Membranes, Gilda Ann Newton Miner Jan 1995

Continuous Electron Stimulated Oxygen Atom Emission From Ag Permeation Membranes, Gilda Ann Newton Miner

Dissertations, Theses, and Masters Projects

No abstract provided.


Characterization Of Nylon-11 Degradation, Leslie Christian Mccullough Jan 1995

Characterization Of Nylon-11 Degradation, Leslie Christian Mccullough

Dissertations, Theses, and Masters Projects

No abstract provided.


Patentability Of Computer Inventions, Robert C. F. Perez Jan 1995

Patentability Of Computer Inventions, Robert C. F. Perez

Dissertations, Theses, and Masters Projects

No abstract provided.


The Characterization Of The Radiative Energy Transfer Process Among Holmium(3+) Ions In Yttrium(3) Aluminum(5) Oxygen(12), Terri Lynn Lazarus Jan 1995

The Characterization Of The Radiative Energy Transfer Process Among Holmium(3+) Ions In Yttrium(3) Aluminum(5) Oxygen(12), Terri Lynn Lazarus

Dissertations, Theses, and Masters Projects

This research comprises a comprehensive spectroscopic study of the characteristics of the solid state crystal YAG (Yttrium Aluminum Garnet) singly doped with Ho (Holmium) ions. An important area of solid state laser crystal research is the determination and optimization of the processes within these laser crystals which lead to efficient laser action. In most laser crystals, there is a donor ion such as Tm (Thulium) and an acceptor ion such as Ho. The donor ion generally has greater absorption than that of the acceptor at the wavelength of the pump source. The donor ion can transfer this absorbed energy to …


Search For Metastability Of 2s Muonic Neon, Bernard Wilhelm Bach Jan 1995

Search For Metastability Of 2s Muonic Neon, Bernard Wilhelm Bach

Dissertations, Theses, and Masters Projects

An experiment was performed at the Paul Scherrer Institut (PSI) to establish the conditions for the metastability of the 2S-state of muonic neon. The muonic atoms were formed by stopping negative muons in the neon-filled target chamber of the PSI cyclotron trap. A pair of intrinsic germanium detectors were used in coincidence to search for the two photon decay of the 2S-state. Both energy and time information from two photon events were written to disk for off-line analysis. Data were accumulated for neon pressures of 40 and 400 Torr. The data were then searched for evidence of two photon transitions …


A Delta-F Monte Carlo Method To Calculate Parameters In Plasmas, Maciek Sasinowski Jan 1995

A Delta-F Monte Carlo Method To Calculate Parameters In Plasmas, Maciek Sasinowski

Dissertations, Theses, and Masters Projects

A Monte Carlo code has been developed which very efficiently calculates plasma parameters, such as currents, potentials and transport coefficients for a fully three dimensional magnetic field configuration. The code computes the deviation, f, of the exact distribution function, f, from the Maxwellian, {dollar}F\sb{lcub}M{rcub},{dollar} with {dollar}\psi{dollar} the toroidal magnetic flux enclosed by a pressure surface and H the Hamiltonian. The particles in the simulation are followed with a traditional Monte Carlo scheme consisting of an orbit step in which new values for the positions and momenta are obtained and a collision step in which a Monte Carlo equivalent of the …


First Principles Linear Response Calculations Of Lattice Dynamics, Cheng-Zhang Wang Jan 1995

First Principles Linear Response Calculations Of Lattice Dynamics, Cheng-Zhang Wang

Dissertations, Theses, and Masters Projects

First principles calculations, using the density-functional theory and particularly the local density approximation (LDA), have achieved remarkable success in studying the properties of solid state systems. Although the basic results of these calculations are the electronic structures (eigenvalues, eigenfunctions, etc.) and the total energy of ground state, many other related physical properties can be deduced from them by investigating their response under external perturbations. Using the linear response method with linearized-augmented-plane-wave (LAPW) basis, we have calculated lattice dynamical properties of important semiconductors CuCl, SiC and ferroelectric KNbO{dollar}\sb3.{dollar} CuCl is known to exhibit large anharmonic effects and possibly a complicated multi-well …


The Synthesis, Characterization, And Application Of Ether-Containing Polymides, Catharine Croall Fay Jan 1995

The Synthesis, Characterization, And Application Of Ether-Containing Polymides, Catharine Croall Fay

Dissertations, Theses, and Masters Projects

Polyimides are a family of heterocyclic polymers that have received extensive evaluation as adhesives, fibers, films, moldings, composite matrices, insulators, coatings, membranes, and resists. their outstanding thermal stability, excellent mechanical and electrical properties, and chemical resistance make them attractive for many applications.;This research developed ether-containing polyimides for three applications: liquid crystalline polyimides as processing aids, polyimides for microelectronic applications, and polyimides for harsh environments. The approach consisted of three primary activities: (1) developed novel diether dianhydrides for polyimide fabrication, (2) designed, characterized, and evaluated polyimide architectures based on the material application requirements, and (3) provided extensive structure-property relationships utilizing a …


The Synthesis Of Benzophenane 3,5-Dicarboxylic Acid For The Double Capping Of Beta-Cyclodextrin, Jaydee Dones Cabral Jan 1995

The Synthesis Of Benzophenane 3,5-Dicarboxylic Acid For The Double Capping Of Beta-Cyclodextrin, Jaydee Dones Cabral

Dissertations, Theses, and Masters Projects

No abstract provided.


Characterization Of Pr500 For Use In Resin Transfer Molding, Rhonda Michelle Barksdale Jan 1995

Characterization Of Pr500 For Use In Resin Transfer Molding, Rhonda Michelle Barksdale

Dissertations, Theses, and Masters Projects

No abstract provided.


Mechanisms Of Poly(Vinyl Chloride) Fire Retardance And Smoke Suppression Induced By Copper Additives, Jong Paul Jeng Jan 1995

Mechanisms Of Poly(Vinyl Chloride) Fire Retardance And Smoke Suppression Induced By Copper Additives, Jong Paul Jeng

Dissertations, Theses, and Masters Projects

The purpose of this study was to elucidate the mechanisms of PVC fire retardance and smoke suppression induced by copper additives.;The experimental approaches involved: (1) the use of activated copper (Cu{dollar}\sp0{dollar}) to study PVC model-compound reactions and the crosslinking of PVC and (2) the pyrolysis of PVC model compounds in the presence of several copper additives in order to examine all of the possible chemical reactions involved in the formation of heavy products.;The results obtained from experiments with activated copper and allylic chloride model compounds suggest that the reductive coupling mechanism is a viable process in PVC. The Cu{dollar}\sp0{dollar} that …


Genetic Relationships Among Geographically Isolated Populations Of Bluefish (Pomatamus Saltatrix), Catherine N. O'Neill Jan 1995

Genetic Relationships Among Geographically Isolated Populations Of Bluefish (Pomatamus Saltatrix), Catherine N. O'Neill

Dissertations, Theses, and Masters Projects

No abstract provided.


Error Analysis In Tidal Wetland Inventory Change Detection: Comparison Of Historical Mapped Wetlands Of The Achilles Quadrangle Between 1976 To 1989, Stacy A. C. Nelson Jan 1995

Error Analysis In Tidal Wetland Inventory Change Detection: Comparison Of Historical Mapped Wetlands Of The Achilles Quadrangle Between 1976 To 1989, Stacy A. C. Nelson

Dissertations, Theses, and Masters Projects

No abstract provided.


Shellfish Culture Area Designation Protocol Development, Orelia Eleta Merchant Jan 1995

Shellfish Culture Area Designation Protocol Development, Orelia Eleta Merchant

Dissertations, Theses, and Masters Projects

No abstract provided.


Acid Dissociation Of Chloroguaiacols And Ph Dependent Sorption To Estuarine Sediments, Jennifer Lisa Gundersen Jan 1995

Acid Dissociation Of Chloroguaiacols And Ph Dependent Sorption To Estuarine Sediments, Jennifer Lisa Gundersen

Dissertations, Theses, and Masters Projects

Chloroguaiacols are common components of bleached kraft pulp mill effluent known to bioaccumulate in aquatic organisms, and sorb onto particulate material and sediments. Ionization properties of the chloroguaiacols must be known in order to explain their sorptive behavior in aquatic systems. to obtain this information, thermodynamic acid dissociation constants (p&K\sb{lcub}\rm a{rcub})& of guaiacol (o-methoxyphenol) and nine chloroguaiacols have been determined by spectrophotometric methods. These experimental p&K\sb{lcub}\rm a{rcub}& values have been compared with literature values, values predicted by the Hammett equation and predictions by quantum chemical calculations using MOPAC 6.0 with AM1 and MNDO Hamiltonian operators. Experimental and predicted acidities were …


Effects Of Sunlight And Seasonal Temperature On Persistence Of Four Bacteriophages In An Estuarine Environment, Terri A. Muller Jan 1995

Effects Of Sunlight And Seasonal Temperature On Persistence Of Four Bacteriophages In An Estuarine Environment, Terri A. Muller

Dissertations, Theses, and Masters Projects

No abstract provided.


Effects Of Simulated Sediment Resuspension Events On The Abundance Of Water Column Bacteria Of Tomales Bay, California, Christopher J. Collumb Jan 1995

Effects Of Simulated Sediment Resuspension Events On The Abundance Of Water Column Bacteria Of Tomales Bay, California, Christopher J. Collumb

Dissertations, Theses, and Masters Projects

No abstract provided.


The Effects Of Hook Type On The Hooking Mortality Of Two Size Classes Of Summer Flounder, Paralichthys Dentatus, Tracy D. Holton Jan 1995

The Effects Of Hook Type On The Hooking Mortality Of Two Size Classes Of Summer Flounder, Paralichthys Dentatus, Tracy D. Holton

Dissertations, Theses, and Masters Projects

No abstract provided.