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Articles 3481 - 3510 of 3797
Full-Text Articles in Physical Sciences and Mathematics
Interpretation Of The Thermal Behavior Of Groundwater In An Alluvial Terrace : Bonneville Dam, Columbia Gorge, Oregon, Richard Stephen Malin
Interpretation Of The Thermal Behavior Of Groundwater In An Alluvial Terrace : Bonneville Dam, Columbia Gorge, Oregon, Richard Stephen Malin
Dissertations and Theses
Groundwater temperature data, collected at an alluvial terrace located on the Oregon shore of the Columbia River downstream from Bonneville Darn, was analyzed in order to characterize and formulate a conceptual model of the thermal data for the groundwater system in the terrace. There is concern that an unlined entrance channel for a new navigation lock, to be located down the middle of the terrace, will widen the range of temperatures in the fish hatchery-groundwater supply. The analysis of temperature behavior in the terrace supports the hydraulic observations derived from analysis of pump test data, but with greater definition of …
Hydrogeology Of An Alluvial Aquifer In The Blue Lake Area, East Multnomah County, Oregon, James Mitchell Wilkinson
Hydrogeology Of An Alluvial Aquifer In The Blue Lake Area, East Multnomah County, Oregon, James Mitchell Wilkinson
Dissertations and Theses
This thesis evaluates the hydraulic relationship between the Blue Lake gravel aquifer, the Columbia River, and Blue Lake. Hydrogeology, water levels, and stable isotopes were used to establish these hydraulic relationships.
Late Holocene Paleoseismicity Along The Northern Oregon Coast, Mark Edward Darienzo
Late Holocene Paleoseismicity Along The Northern Oregon Coast, Mark Edward Darienzo
Dissertations and Theses
Marsh paleoseismological studies were conducted in four bays (Necanicum, Nestucca, Siletz, and Yaquina) along the northern Oregon coast and compared with completed studies in two other bays (Netarts and Alsea). Coseismically buried peats were identified in all bays, based on 1) abrupt contacts, decreases in organic content, increases in sand content, increases in beach sand, and changes in diatom assemblages, all from the peat to the overlying sediments, 2) distinct sandy layers and key plant macrofossils, such as Triglochin, above the buried peat, and 3) widespread correlation of the buried peats within the bay. The stratigraphy and the ages and …
Transient Heat Transfer, Eric Roth
Transient Heat Transfer, Eric Roth
Dissertations and Theses
With the advent of the new high Tc superconductors, liquid nitrogen will be one of the preferred cryogens used to cool these materials. Consequently, a more thorough understanding of the heat transfer characteristics of liquid nitrogen is required. In our investigations we examine the transient heating characteristics of liquid nitrogen to states of nucleate and film boiling under different liquid flow conditions. Using a platinum hot wire technique, it is verified that there is a premature transition to film boiling in the transient case at power levels significantly lower than under steady state nucleate boiling conditions. It is also shown …
Limnology Of Two New Lakes, Mount St. Helens, Wa, Valerie Jean Kelly
Limnology Of Two New Lakes, Mount St. Helens, Wa, Valerie Jean Kelly
Dissertations and Theses
Coldwater Lake and Castle Lake are two new lakes which were formed in the aftermath of the volcanic eruption of Mount St . Helens, WA in May, 1980. This research describes the limnology of these lakes ten years later, and includes physical, chemical, and biological parameters. The two lakes are compared and contrasted. Previous research on the eruption and its aftermath, as well as earlier studies of the lakes are described.
Gravitational Synchrotron Radiation From Cosmic Strings, Alan Cresswell, Robert L. Zimmerman
Gravitational Synchrotron Radiation From Cosmic Strings, Alan Cresswell, Robert L. Zimmerman
Physics Faculty Publications and Presentations
This work studies the gravitational synchrotron radiation emitted from arbitrary cusps of cosmic strings. The results are expressed in terms of four parameters describing the motion of such a cusp. The power spectrum is derived for cusps moving at unit velocity. By using a phenomenological approach the authors also derive the power emitted when the radiation reaction on the cusps is taken into account. In both cases, the synchrotron nature of the radiation produces a power spectrum emitted in a narrow forward cone. If cosmic strings do exist, the radiation emitted by their cusps would seem to be a potential …
Third-Generation Fage Instrument For Tropospheric Hydroxyl Radical Measurement, C. Y. Chan, Thomas M. Hard, A. A. Mehrabzadeh, Robert J. O'Brien
Third-Generation Fage Instrument For Tropospheric Hydroxyl Radical Measurement, C. Y. Chan, Thomas M. Hard, A. A. Mehrabzadeh, Robert J. O'Brien
Environmental Science and Management Faculty Publications and Presentations
The authors have constructed a single-stage, frequency-doubled, copper vapor laser-pumped dye laser to be used in the measurement of atmospheric hydroxyl radical concentrations. This laser can be tuned to either the 1← 0 or 0← 0 vibrational transition in the electronic transition ²Sigmalarr²Pi. A new photon counting instrument is used for HO fluorescence detection. Theoretical and experimental studies of instrument performance show better sensitivities and reduced photolytic interferences than have been possible with previous systems based upon Nd:YAG pumping.
Bis(1h+-Pyrazinium N4-Oxide) Dichromate, Gary L. Gard, Roger D. Willett, W. W. Paudler, R. M. Sheets, Mark R. Pressprich
Bis(1h+-Pyrazinium N4-Oxide) Dichromate, Gary L. Gard, Roger D. Willett, W. W. Paudler, R. M. Sheets, Mark R. Pressprich
Chemistry Faculty Publications and Presentations
2C₄H₅N₂O⁺.Cr₂O²₇⁻, Mᵣ=410∙2, monoclinic, P2₁, a=8∙(2), b=6∙132 (2), c=14∙493 (4) Å, β=94∙50 (2)°, V=708∙8 (3) ų, Z=2, Dₓ=1∙92 g cm⁻³, Mο Κα, λ=0∙71069 Å, μ=15∙5 cm⁻¹, F(000)=412, T=293 K, R=0∙0602 for 1980 unique observed reflections with F≥3σ(F). The structure consists of discrete dinegative dichromate anions hydrogen bonded to monopositive pyrazinium N-oxide cations (N―H∙∙∙O=2∙724, 2∙644 Å). A strong hydrogen bond to the bridging O atom in the Cr₂O²₇⁻ anion leads to significant lengthening of the bridging Cr―O bonds. A short C―H∙∙∙O interaction (3∙180 Å) is also observed.
Distribution Of Sand Within Selected Littoral Cells Of The Pacific Northwest, Don Joseph Pettit
Distribution Of Sand Within Selected Littoral Cells Of The Pacific Northwest, Don Joseph Pettit
Dissertations and Theses
Beach sand acts as a buffer to wave energy, protecting the shoreline from erosion. Estimates of the quantity and distribution of beach sand in littoral cells of the PNW are critical to the understanding and prediction of shoreline erosion or accretion. This study was initiated in order to: 1) document the distribution of sand in littoral cells of the Pacific Northwest; 2) determine the factors which have brought about these present distributions; and 3) address the relationship of beach sand distribution to shoreline stability.
Administrative Design For Yakima-Klickitat Production Project: Final Report, Jack Churchill, Lee Shissler, Sheldon Edner, Randy Smith
Administrative Design For Yakima-Klickitat Production Project: Final Report, Jack Churchill, Lee Shissler, Sheldon Edner, Randy Smith
Center for Urban Studies Publications and Reports
This report provides the administrative design to implement the Yakima/Klickitat Production Project. This project is a scientifically designed salmon fishery restoration project funded by the Bonneville Power Administration in compliance with the .fishery policies established by the Northwest Power Planning Council under the authority of the Northwest Power Planning Act.
This project breaks new ground in the field of fishery management. It is the first full scale application of supplementation technology directed toward maintaining and rebuilding native fish stocks and sub stocks with hatchery rearing methods. The work of the organization is an inherently more complex production function than traditional …
Gravity Maps, Models And Analysis Of The Greater Portland Area, Oregon, Paul T. Beeson
Gravity Maps, Models And Analysis Of The Greater Portland Area, Oregon, Paul T. Beeson
Dissertations and Theses
Growing concern over earthquakes in the Pacific Northwest has prompted the mapping and location of near surface faults in the Portland area, Oregon. Visible evidence of faults is poor, requiring the use of geophysical methods to assist in mapping and defining structures in the basin. Gravity maps and models may help in addressing this problem.
Two free-air gravity models were produced. The first model constructed from existing data crosses the basin from Petes Mountain northeast to the Columbia River. The second model is from a gravity survey along Forsythe Road near Clackamas Heights.
The line crossing the basin confirms previous …
Reduced Form For Coulomb-Wave Multicenter Integrals, Jack C. Straton
Reduced Form For Coulomb-Wave Multicenter Integrals, Jack C. Straton
Physics Faculty Publications and Presentations
In a previous paper [J. C. Straton, Phys. Rev. A 41, 71 (1990)] an integro-differential transform was introduced and utilized to obtain the analytically reduced form for multicenter integrals composed of general-state hydrogenic orbitals, Yukawa or Coulomb potentials, and plane waves. The present paper extends this result to include Coulomb waves.
Geochemical Evolution Of Ferruginous Bauxite Deposits In Northwestern Oregon And Southwestern Washington, Joseph Michael Fassio
Geochemical Evolution Of Ferruginous Bauxite Deposits In Northwestern Oregon And Southwestern Washington, Joseph Michael Fassio
Dissertations and Theses
Ferruginous bauxite deposits developed from flows of the Columbia River Basalt Group in northwestern Oregon and southwestern Washington. Samples of the iron pisolite and the gibbsite nodular zones from the upper portion of the weathering profile of drill core from Columbia County, Oregon and Cowlitz County, Washington, were analyzed by instrumental neutron activation. The mineralogy was determined using Xray diffraction and Mossbauer spectroscopy.
The gibbsite nodular zone is above the clay-rich saprolite or relic basalt zone. The nodules contain relic vesicles and well preserved relic plagioclase microlites. Gibbsite occurs with poorly crystalline goethite and hematite in the gibbsite nodular zone. …
Decay Of Molecules At Spherical Surfaces: Nonlocal Effects, P.T. Leung
Decay Of Molecules At Spherical Surfaces: Nonlocal Effects, P.T. Leung
Physics Faculty Publications and Presentations
The decay rates for molecules in the vicinity of a metallic sphere are investigated in a phenomenological approach for very close molecule-surface distances d. The Fuchs-Claro model [Phys. Rev. B 35, 3722 (1987)] is adopted to describe the polarizability of the sphere with the nonlocal dielectric response being accounted for within the hydrodynamic description. The results show significant differences when compared with those obtained previously within a local description for dlsim50 Aring, with extra resonances observed in the high-frequency regime, a phenomenon similar to that noted previously by Ruppin (1982), in his calculation of the extinction cross section for such …
The Effect Of Hot Dense Hydrogen And Argon In A Ballistic Compressor On The Structure And Composition Of Pure Iron, David Samuel Silver
The Effect Of Hot Dense Hydrogen And Argon In A Ballistic Compressor On The Structure And Composition Of Pure Iron, David Samuel Silver
Dissertations and Theses
An experimental study of pure iron foil exposed to a hot, dense hydrogen and argon gas mixture in a ballistic compressor yielded evidence of structural and compositional changes of the metal due to the presence of the hydrogen gas. Three iron foils have been compared, one of unexposed pure iron, another of pure iron exposed to a mixture of hydrogen and argon gas, and the third of pure iron exposed to argon alone. Exposure to these high temperature, high pressure gases took place in a ballistic compressor.
Line formations were found on the surface of the iron foil exposed to …
Modeling Coastal Landscape Dynamics, Robert Costanza, Fred Hal Sklar, Mary L. White
Modeling Coastal Landscape Dynamics, Robert Costanza, Fred Hal Sklar, Mary L. White
Institute for Sustainable Solutions Publications and Presentations
Examines methods used to predict the way ecological systems respond to human modifications. Coastal marshes; Process-based dynamic spatial ecosystem simulation models; Coastal ecological landscape spatial simulation model; Scenario analysis.
High-Velocity Limits For The Ratio Of Double To Single Ionisation Of Helium By Projectiles With Electrons, Y. D. Wang, Jack C. Straton, James H. Mcguire, R. D. Dubois
High-Velocity Limits For The Ratio Of Double To Single Ionisation Of Helium By Projectiles With Electrons, Y. D. Wang, Jack C. Straton, James H. Mcguire, R. D. Dubois
Physics Faculty Publications and Presentations
The ratio of total double to total single ionisation cross sections, R, by high velocity projectiles containing electrons is examined in the first Born approximation. For ionisation of helium by H+, H0 and He0 impact, it is found that t filt H+ < filt Ho < filt Heo . Connection with Bohr's free-collision model for collisions with projectile electrons is given.
Self-Consistent Effective Binary Diffusion In Multicomponent Gas Mixtures, John D. Ramshaw
Self-Consistent Effective Binary Diffusion In Multicomponent Gas Mixtures, John D. Ramshaw
Physics Faculty Publications and Presentations
The correct treatment of diffusion in multicomponent gas mixtures requires solution of a linear system of equations for the diffusive mass fluxes relative to the mass-averaged velocity of the mixture. Effective binary diffusion approximations are often used to avoid solving this system. These approximations are generally internally inconsistent in the sense that the approximate diffusion fluxes do not properly sum to zero. The origin of this inconsistency is identified, and a general procedure for removing it is presented. This procedure applies equally to concentration, forced, pressure, and thermal diffusion, either separately or in combination. It is used to obtain a …
Reduced Form For The General-State Multicenter Integral From An Integro-Differential Transform, Jack C. Straton
Reduced Form For The General-State Multicenter Integral From An Integro-Differential Transform, Jack C. Straton
Physics Faculty Publications and Presentations
In a previous paper Gaussian transforms were utilized to obtain the analytically reduced form for the class of multicenter integrals containing a product of hydrogenic orbitals for s states, Yukawa or Coulomb potentials, and plane waves. In the present paper a related transformation is developed for nonspherical functions, leading to the reduced form for multicenter integrals that include hydrogenic orbitals representing states of arbitrary angular momentum.
Benchmarking Parallel Machines Via A Software Architecture, Srikanth Kambhatla, Jon Inouye, Jonathan Walpole
Benchmarking Parallel Machines Via A Software Architecture, Srikanth Kambhatla, Jon Inouye, Jonathan Walpole
Computer Science Faculty Publications and Presentations
The diversity in parallel architectures and the programming styles induced thereof, make benchmarking of parallel machines a hard problem. Current benchmarking techniques are limited in applicability due to the issues of portability. We present a different approach to benchmarking parallel machines, which would make the resulting benchmarks portable, easy to use and widely applicable. The approach involves the use of a software architecture to mask the diversities of the underlying architectures. The benchmarks are based on the Linda Tuple Space, and is called BeLinda. In this report, we motivate the use of a software architecture, give a specification of the …
Chemistry Of Pentafluorothio (Sf5) Alkyl Derivatives, Rolf Walter Winter
Chemistry Of Pentafluorothio (Sf5) Alkyl Derivatives, Rolf Walter Winter
Dissertations and Theses
Part I describes the preparation of a number of useful intermediates from the sultone F5SCHCF2OSO2 (1). These intermediates include the following: the ketene F5SC(SO2)=C=O (21), the unique sultone F4S=CCF2OSO2 (23), and various ionic intermediates of the form Y+ [F5SC(SO2F) COX]-. These intermediates play an important role in providing new pathways for preparing fluorosulfonic acid precursors. Fluorosulfonic acids are excellent candidates to improve the efficiency of environmentally safe fuel cells. It was possible to obtain new derivatives of 1 by …
Subsurface And Geochemical Stratigraphy Of Northwestern Oregon, Olga Berenice Lira
Subsurface And Geochemical Stratigraphy Of Northwestern Oregon, Olga Berenice Lira
Dissertations and Theses
Lithological, geophysical, paleontological and geochemical methods were used in order to define the contact relationship between the Keasey and the Cowlitz formations in northwestern Oregon. Drill cuttings from six wells located in Columbia County were analyzed by the Instrumental Neutron Activation Analysis (INAA) method. The concentrations of K, Th, Rb and Sc/Co ratio in the samples established four different groups: 1) High K, Rb, and TH, with low Sc/Co ratio typical of Cowlitz sediments. 2) Low K, Th and Rb and high Sc/Co ratio, more characteristics of the Keasey Formation. 3) Very low concentrations of Rb and high Sc, which …
Instrumentation For Multi-Electrode Voltammetry, I-Pin Ho
Instrumentation For Multi-Electrode Voltammetry, I-Pin Ho
Dissertations and Theses
When metal pollutants exist in natural water, their toxicity is dramatically dependent on the chemical species. Numerous sophisticated techniques and instruments have been developed to detect metal pollutants at very low concentration levels. However, one important factor is often ignored, i.e., rarely is species determination required. Electrochemical (EC) methods have the particular advantage of being, in principle, a species-sensitive method rather than an element-sensitive method for the study of metal speciation in natural waters.
The goal of this research was to develop an instrument using the EC technique for speciation and general voltammetric studies. It was accomplished by designing a …
Optimization And Thermodynamic Performance Measures Of A Class Of Finite Time Thermodynamic Cycles, Joseph D. Walters
Optimization And Thermodynamic Performance Measures Of A Class Of Finite Time Thermodynamic Cycles, Joseph D. Walters
Dissertations and Theses
Modifications to the quasistatic Carnot cycle are developed in order to formulate improved theoretical bounds on the thermal efficiency of certain refrigeration cycles that produce finite cooling power. The modified refrigeration cycle is based on the idealized endoreversible finite time cycle. Two of the four cycle branches are reversible adiabats, and the other two are the high and low temperature branches along which finite heat fluxes couple the refrigeration cycle with external heat reservoirs.
This finite time model has been used to obtain the following results: First, the performance of a finite time Carnot refrigeration cycle (FTCRC) is examined. In …
Performance Analysis Of A Distributed File System, Meenakshi Mukhopadhyay
Performance Analysis Of A Distributed File System, Meenakshi Mukhopadhyay
Dissertations and Theses
An important design goal of a distributed file system, a component of many distributed systems, is to provide UNIX file access semantics, e.g., the result of any write system call is visible by all processes as soon as the call completes. In a distributed environment, these semantics are difficult to implement because processes on different machines do not share kernel cache and data structures. Strong data consistency guarantees may be provided only at the expense of performance.
This work investigates the time costs paid by AFS 3.0, which uses a callback mechanism to provide consistency guarantees, and those paid by …
Analysis And Numerical Simulation Of The Ground Water System At The Bonneville Navigation Lock Site, Oregon, Dirk Baron
Analysis And Numerical Simulation Of The Ground Water System At The Bonneville Navigation Lock Site, Oregon, Dirk Baron
Dissertations and Theses
As part of the new navigation lock for Bonneville Dam a new water source for the Bonneville Fish Hatchery must be supplied. The hatchery is located on the Oregon side of the Columbia River downstream of the dam. It requires large quantities of water free from chemical and biological contamination. In addition, the water has to be in a narrow temperature range. Currently the fish hatchery receives its water from a well field that is located on the alluvial terrace downstream of Bonneville Dam. The well field lies in the proposed approach channel for the new lock and has to …
A Theoretical And Experimental Study Of The Three-Ring Electrostatic Electron Lens, Thomas Anthony Sommer
A Theoretical And Experimental Study Of The Three-Ring Electrostatic Electron Lens, Thomas Anthony Sommer
Dissertations and Theses
A theoretical and experimental study of the three-ring electrostatic lens is presented. The lens consists of three isolated ring-shaped conductors, equally spaced along a common axis of symmetry. When appropriate potentials are applied to the conductors an electric field is produced near the axis which is capable of focusing a collimated beam of electrons. In the theoretical study the charge density method is used to find a closed-form solution for the field. This method approximates the field by replacing each ring with an infinitely thin hoop of uniform charge. The radial and axial equations of motion are then solved numerically, …
Frequency-Dependent Seed Dispersal By Ants Of Two Deciduous Forest Herbs, Brent H. Smith, Catherine E. De Rivera, Cara Lin Bridgman, John J. Woid
Frequency-Dependent Seed Dispersal By Ants Of Two Deciduous Forest Herbs, Brent H. Smith, Catherine E. De Rivera, Cara Lin Bridgman, John J. Woid
Environmental Science and Management Faculty Publications and Presentations
Two co—occurring deciduous forest myrmecochores, Asarum canadense and Jeffersonia diphylla, release their seeds at approximately the same time, and therefore potentially compete for ants as dispersers. Within a single woodlot, we placed seeds of both species inside a dense Jeffersonia population away from Asarum plants, inside a dense Asarum population away from Jeffersonia plants, and in a site where plants of neither species occurred. No preference was exhibited by ants where natural populations were absent. Preference at the other two sites was frequency dependent: ants preferred seeds of the introduced species. Species preferred by ants have higher seed and …
Bethe Stopping-Power Theory For Heavy-Target Atoms, P.T. Leung
Bethe Stopping-Power Theory For Heavy-Target Atoms, P.T. Leung
Physics Faculty Publications and Presentations
The Bethe stopping-power theory is considered in the context of heavy target atoms in which the relativistic effects of the target electrons are partially accounted for within the semirelativistic and independent-particle description. Numerical results show that, for target elements with large atomic numbers, these relativistic effects can become comparable with other corrections such as the shell correction, the Barkas effect, and the Bloch term.
Post-Prior Symmetrical First-Order T Matrix For Charge Transfer, Jack C. Straton, M. D. Girardeau
Post-Prior Symmetrical First-Order T Matrix For Charge Transfer, Jack C. Straton, M. D. Girardeau
Physics Faculty Publications and Presentations
The Fock-Tani Hamiltonian is found for systems containing two protons and one electron. It is shown that a post-prior symmetrical T-matrix element for a+ + (b+ c-)→(a+ c-)+b+ may be found from that of the simpler proton-proton-electron system if a and b are treated as isospin projections of a single type of nucleon. The Coulomb-exchange contribution to the inelastic (isospin flip) scattering of this system gives a first-order T matrix that is completely symmetrical with respect to post and prior interactions and orthogonalizations, a symmetry of the exact …