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Articles 3631 - 3660 of 3797
Full-Text Articles in Physical Sciences and Mathematics
Entropy Measure In Input-Output Analysis, Martin Zwick, Abbas Heiat
Entropy Measure In Input-Output Analysis, Martin Zwick, Abbas Heiat
Systems Science Faculty Publications and Presentations
Applications of Shannon's entropy measure to the matrices of technical and interdependence coefficients, to the final demand vector, and to other aspects of input- output tables are proposed. These entropy measures serve as indices of different types of economic diversity. The relevance of such indices for economic planning and for analyses of economic structural complexity and development is discussed.
Hydroxide Binding Equilibrium In Hemerythrin, John David Mccallum
Hydroxide Binding Equilibrium In Hemerythrin, John David Mccallum
Dissertations and Theses
The measurement of the equilibrium constant and the thermodynamic parameters of the binding of hydroxide ions to the active site of hemerythrin, an invertebrate iron containing protein, was done by a new difference spectroscopic method. The method enables accurate measurements of equilibrium constants without accurate knowledge of molar absorptivities or protein concentrations and is novel in that it takes the difference between the two equilibrium mixtures, thus enabling the measurement of equilibrium constants when it is not convenient or possible to produce either substance as a pure reference material.
An Investigation Of Cadmium And Sulfur Reactions In Dimethylsulfoxide, Howard W. Hogle
An Investigation Of Cadmium And Sulfur Reactions In Dimethylsulfoxide, Howard W. Hogle
Dissertations and Theses
The study of the reaction of cadmium and sulfur in dimethylsulfoxide (DMSO) is presented. Specifically, the reaction of dissolved molecular sulfur in DMSO at temperatures greater than 90°C with freshly precipitated metallic cadmium is followed by UV-visible spectrometry, atomic absorption spectrometry, and Raman spectrometry. Evidence for the formation of a new cadmium-sulfur species and S3- is discussed. In a second reaction, an equilibrium sodium polysulfide solution in DMSO is titrated with a solution of cadmium ion at room temperature and the reaction progress is followed by means of UV-visible spectrometry. A calculation of the average number of polysulfide …
The Determination Of A Relative Chronology For A Surface Archeological Site Using The Obsidian Hydration Dating Method, Scott Preston Thomas
The Determination Of A Relative Chronology For A Surface Archeological Site Using The Obsidian Hydration Dating Method, Scott Preston Thomas
Dissertations and Theses
This methodological study is an attempt to develop relative chronologies for surface archaeological sites from the obsidian hydration analysis of waste flake samples. Two sites in southeastern Oregon were selected and their surface components sampled. The results of the obsidian hydration analysis indicate, that with the use of random sampling methods and general geochemical control, a fairly accurate representation of the history of an archaeological surface site can be obtained.
Chemistry Of Chromium Oxyfluorides And Group Vib Perfluoroglutarates, Bruce Michael Johnson
Chemistry Of Chromium Oxyfluorides And Group Vib Perfluoroglutarates, Bruce Michael Johnson
Dissertations and Theses
Pure chromium oxide trifluoride was prepared for the first time by reaction of CrO₃ and ClF with subsequent multiple fluorine treatments at 120°C. On the basis of its infrared spectrum, the purple CrOF₃ was assigned as a fluorine-bridged polymer with terminal oxygen groups. Chromium oxide trifluoride was found to be stable to 300°C, where it decomposes with the loss of oxygen to CrF₃.
Massive Neutrinos And The Stellar Stopping Power Via The Neutrino Magnetic Moment, P.T. Leung, M. L. Rustgi, J. E. Turner, Werner Brandt
Massive Neutrinos And The Stellar Stopping Power Via The Neutrino Magnetic Moment, P.T. Leung, M. L. Rustgi, J. E. Turner, Werner Brandt
Physics Faculty Publications and Presentations
An exact expression is derived within the high-Q approximation for the spectrum of energy losses of neutrinos interacting via their magnetic moment with electrons. A formula for the stopping power of matter for neutrinos is derived and applied to the study of the solar neutrino anomaly. The total inelastic cross section is given. An upper limit is deduced for the neutrino magnetic moment from the antineutrino spectrum as recently parameterized by Lee (1979). It confirms the bound reported by Cowan and Reines. The distance for stellar neutrinos to thermalize by the interactions studied here, through encounters with stars is found …
Existence Of The Dielectric Constant In Dipolar Fluid Mixtures, John D. Ramshaw, Norman D. Hamer
Existence Of The Dielectric Constant In Dipolar Fluid Mixtures, John D. Ramshaw, Norman D. Hamer
Physics Faculty Publications and Presentations
The existence of the dielectric constant epsilon is investigated for fluid mixtures of rigid polar molecules. The investigation is performed using the functional-derivative formalism for mixtures, and is closely analogous to that previously carried out for pure dipolar fluids (J. Chem. Phys. 68, 5199 (1978)). Sufficient conditions for the existence of epsilon are obtained in terms of the direct correlation function matrix c/sub alphabeta/(12). It is found that epsilon exists if c/sub alphabeta/(12) depends only on relative positions and orientations, and becomes asymptotic to -theta/sub alphabeta/(12)/kT at long range, where theta/sub alphabeta/(12) is the dipole--dipole potential between a molecule of …
Time-Dependent Direct Correlation Function, John D. Ramshaw
Time-Dependent Direct Correlation Function, John D. Ramshaw
Physics Faculty Publications and Presentations
A time-dependent direct correlation function (TDDCF) is defined and discussed. The definition (which differs from that proposed by Percus and Yevick) is motivated by linear response theory. The TDDCF consequently has a functional-derivative or stimulus-response interpretation closely analogous to that of the static direct correlation function. Mean-field considerations suggest that the TDDCF separates into a term which is simply related to the pair potential and a spatially shorter-ranged remainder. This behavior is confirmed in the Vlasov-Zwanzig approximation.
Geology Of A Volcanic Complex On The South Flank Of Mount Jefferson, Oregon, Brian Lee Gannon
Geology Of A Volcanic Complex On The South Flank Of Mount Jefferson, Oregon, Brian Lee Gannon
Dissertations and Theses
The volcanic stratigraphy and petrography is described for a 46 km2 area on the southern flank of Mount Jefferson in the north-central part of the Oregon High Cascades. Here, volcanic processes have been active throughout Quaternary time, resulting in complex stratigraphic relationships. In addition, three formerly recognized glaciations and a two-phase period of neoglaciation have eroded the terrain, depositing tills in contact or interstratified with the volcanic units. Collectively, these processes and the resulting deposits are characteristic of High Cascades development.
Brownian Motion In A Flowing Fluid Revisited, John D. Ramshaw
Brownian Motion In A Flowing Fluid Revisited, John D. Ramshaw
Physics Faculty Publications and Presentations
It is shown how the phenomenon of osmosis may be treated using the phenomenological theory of Brownian motion in a flowing fluid. The theory is also generalized to include viscous stresses in the particle and mixture momentum equations.
X-Ray Survey Of The Small Magellanic Cloud, F. D. Seward, Melanie Mitchell
X-Ray Survey Of The Small Magellanic Cloud, F. D. Seward, Melanie Mitchell
Computer Science Faculty Publications and Presentations
A region of over 40 square degrees centered on the Small Magellanic Cloud (SMC) has been surveyed with the imaging instruments of the Einstein Observatory. The survey is approximately complete to Lx = 1036 ergs s-1, and the faintest source detected in the SMC, has Lx ≈ 3 x 1035 ergs s-1. Twenty-six sources were clearly seen. Five are identified with objects not associated with the SMC. The only previously known source detected was SMC X-1 which, when in a high state, is the brightest source in the SMC. The second brightest source observed, …
Stratigraphy, Lithofacies And Depositional Environment Of The Cowlitz Formation, T. 4 And 5n., R. 5w. Northwest Oregon, Dale M. Timmons
Stratigraphy, Lithofacies And Depositional Environment Of The Cowlitz Formation, T. 4 And 5n., R. 5w. Northwest Oregon, Dale M. Timmons
Dissertations and Theses
The Cowlitz Formation in southern Columbia and Clatsop counties, northwest Oregon was studied in order to prepare a geologic map of parts of this formation and to determine the character of its lithofacies and the environments of deposition.
The Structure, Geologic Evolution And Regional Significance Of The Bethel Creek-North Fork Area, Coos And Curry Counties, Oregon, Carl Fredrick Gullixson
The Structure, Geologic Evolution And Regional Significance Of The Bethel Creek-North Fork Area, Coos And Curry Counties, Oregon, Carl Fredrick Gullixson
Dissertations and Theses
The original purpose of this study was a detailed structural analysis of the Jurassic Otter Point Formation in order to determine if the Canyonville Fault Zone, which forms the northern boundary of the Klamath Mountains in the Riddle - Canyonville area (Benson and Perttu, 1980), extends westward to the coast and, if possible, to characterize the structure of the Otter Point Formation. Further, a detailed examination of the structural and stratigraphic relationships between the Otter Point Formation and the Eocene Roseburg and Lookingglass Formations was to be performed in an attempt to determine the tectonic history of the area.
A Stratigraphic And Geochemical Investigation Of Ferruginous Bauxite Deposits In The Salem Hills, Marion County, Oregon, Charles William Hoffman
A Stratigraphic And Geochemical Investigation Of Ferruginous Bauxite Deposits In The Salem Hills, Marion County, Oregon, Charles William Hoffman
Dissertations and Theses
Pacific Northwest ferruginous bauxite deposits have formed in four main areas of northwestern Oregon and southwestern Washington by laterization of flows of the Columbia River Basalt Group (CRBG). The deposits, averaging 36.3% Al2O3 , 31.8% Fe2O3 , and 5.9% Sio2, generally occur near the surface of hilltops in gently rolling areas. Two very different views have been advanced regarding the setting in which the deposits have formed. The first hypothesis calls for a blanket-type laterization by erosion of much of the original deposit upon uplift and dissection of the area.
The Influence Of Halloysite Content On The Shear Strength Of Kaolinite, Reka Katalin Gabor
The Influence Of Halloysite Content On The Shear Strength Of Kaolinite, Reka Katalin Gabor
Dissertations and Theses
The objective of this thesis is to determine the relative shear strengths of halloysite, kaolinite, synthetic mixtures, and local soils, to investigate the influence of halloysite content on the shear strength of kaolinite, and to explore the possibility that the strength properties of soil clays might be controlled by the relative content of their component minerals.
The Stratigraphy And Structure Of The Columbia River Basalt Group In The Bull Run Watershed, Multnomah And Clackamas Counties, Oregon, Beverly Frobenius Vogt
The Stratigraphy And Structure Of The Columbia River Basalt Group In The Bull Run Watershed, Multnomah And Clackamas Counties, Oregon, Beverly Frobenius Vogt
Dissertations and Theses
Approximately 150 meters (500 feet) of Grande Ronde Basalt and 140 meters (450 feet) of Wanapum Basalt of the Columbia River Basalt Group are exposed in the Bull Run Watershed. In Bull Run, the Grande Ronde Basalt is divided into three mappable units: "low Mg" R2 (at least one flow), "low Mg" N2 (approximately four flows), and "high Mg" N2 (two to three flows}. The Wanapum Basalt is represented by two members: Frenchman Springs Member (six flows) and Priest Rapids Member (one flow). These units are identified by instrumental neutron activation analysis, paleomagnetism based on measurements with …
Rheological Properties Of Mudflows Associated With The May 1980 Eruptions Of Mount St. Helens Volcano, Washington, Jonathan H. Fink, Michael C. Malin, Richard E. D'Alli, Ronald Greeley
Rheological Properties Of Mudflows Associated With The May 1980 Eruptions Of Mount St. Helens Volcano, Washington, Jonathan H. Fink, Michael C. Malin, Richard E. D'Alli, Ronald Greeley
Geology Faculty Publications and Presentations
Rheological properties of three recent mudflows at Mount St. Helens were estimated using techniques developed for determining the properties of debris flows based on the geometry of their deposits. Calculated yield strengths of 1100, 1000, and 400 Pa, maximum flow velocities of 10 to 31 m/s, volumetric flow rates of 300 to 3400 m3/s, and plastic viscosities of 20 to 320 Pa-s all compare favorably with measured and estimated values cited in the literature. A method for determining likely sites of future mudflow initiation based on these data is outlined.
Isolation And Characterization Of Frullanolide From Frullania Franciscana (Howe), Marshall Stuart Sass
Isolation And Characterization Of Frullanolide From Frullania Franciscana (Howe), Marshall Stuart Sass
Dissertations and Theses
Investigation of the ether extract of the liverwort Frullania franciscana (Howe) resulted in the isolation of the sesquiterpene lactone frullanolide. The separation techniques of thin-layer chromatography, dry column chromatography, and liquid column chromatography were evaluated. Only liquid column chromatography was found useful. Fractions from alumina liquid column separations had infrared spectra which resembled the published spectrum of frullanolide. The identity of the compound obtained from F. franciscana (Howe) was established after extensive purification by comparison of its infrared and nuclear magnetic resonance spectra with published spectra of frullanolide.
A Study Of Leslie Model Under Stochastic Environments, Kamran Shaukat
A Study Of Leslie Model Under Stochastic Environments, Kamran Shaukat
Dissertations and Theses
The prediction and analysis of changes in the numbers of biological populations rest on mathematical formulations of demographic events (births and deaths) classified by the age of individuals. The development of demographic theory when birth and death rates vary statistically over time is the central theme of this work. A study of the standard Leslie model for the demographic dynamics of populations in variable environments is made. At each time interval a Leslie matrix of survival rates and fertilities of a population is chosen according to a Markov process and the population numbers in different age classes are computed. Analytical …
Preliminary Inventory Of Lifeline Systems And Evaluation Of Seismic Hazards In Reno And Sparks, Nevada, Barbara Priest
Preliminary Inventory Of Lifeline Systems And Evaluation Of Seismic Hazards In Reno And Sparks, Nevada, Barbara Priest
Dissertations and Theses
The Reno-Sparks community is in a seismically hazardous area. Recent research indicates that a Richter 7.0 or greater magnitude earthquake could affect the area. Many of the emergency and essential facilities are situated in dangerous geological locations and are housed in outdated structures which could be severely damaged in the event of a major earthquake. Detailed site evaluations need to be made with respect to location of new structures and of existing building safety. The 1979 Unified Building Code seismic provisions should be adopted without exception; Nevada Revised Statute 278 .160 needs to be revised to require a seismic safety …
Stratigraphy, Lithofacies, And Environment Of Deposition Of The Scappoose Formation In Central Columbia County, Oregon, Kevin Blair Kelty
Stratigraphy, Lithofacies, And Environment Of Deposition Of The Scappoose Formation In Central Columbia County, Oregon, Kevin Blair Kelty
Dissertations and Theses
The study area is located in central Columbia County and encompasses approximately 373 square kilometers. The purpose of the study was to map lithofacies to a scale of 1:31250, study the petrography of the lithofacies, determine the stratigraphy, and develop a model for environment of deposition of the Scappoose Formation.
Stopping Power Of Matter For Alpha Particles At Extreme Relativistic Energies, P.T. Leung, M. L. Rustgi, J. E. Turner
Stopping Power Of Matter For Alpha Particles At Extreme Relativistic Energies, P.T. Leung, M. L. Rustgi, J. E. Turner
Physics Faculty Publications and Presentations
The stopping power of matter for alpha particles at extreme relativistic energies has been calculated by incorporating the charge form factor. A table is presented for aluminum, copper, and lead. It is found that at the highest energies considered, inclusion of form factor reduces the mass stopping power by about 6-8% in comparison with that predicted by Bethe's relativistic formula.
Dielectric Saturation In Dipolar Fluids. I. The Single-Molecule Distribution Function, John D. Ramshaw
Dielectric Saturation In Dipolar Fluids. I. The Single-Molecule Distribution Function, John D. Ramshaw
Physics Faculty Publications and Presentations
The functional-derivative formalism is used to investigate the form of the equilibrium single-molecule distribution function n(1) in a finite fluid system of rigid polar molecules subjected to a strong external electric field that varies slowly with position. The investigation is based on the assumption that the long-range asymptotic behavior of the direct correlation function is independent of the external field, and is hence the same as in the unperturbed fluid. This assumption implies that n(1) has the form of a single-molecule Boltzmann factor in which the interaction energy is that of a deformable quasidipole with the local Lorentz electric field …
Electrostatic Tem Studies Of Magnetic Domains In Thin Iron Films, Hideaki Karamon
Electrostatic Tem Studies Of Magnetic Domains In Thin Iron Films, Hideaki Karamon
Dissertations and Theses
An electron microscope with electrostatic lenses was used for high resolution studies of magnetic domains in thin iron films.
Observation methods used to determine the directions of local magnetization in iron thin films were the Lorentz method and the Foucault method.
We studied how Bloch line-crosstie pairs and crosstie main walls behave in applied, in-plane magnetic fields. We found that crosstie main walls remain unchanged until crosstie density goes nearly to zero when the field is applied perpendicular to the main wall. A twisted type of domain appears where crossties disappear.
An Analysis Of Gravity Surveys In The Portland Basin, Oregon, Janice C. Perttu
An Analysis Of Gravity Surveys In The Portland Basin, Oregon, Janice C. Perttu
Dissertations and Theses
The geologic setting of the Portland Basin is ideal for gravity surveys because of the large density contrasts between geologic units. The Portland Basin consists of a north-northwest-trending syncline in the Columbia River basalt overlain by Pliocene to Recent alluvium. This study was undertaken to define structures in the Portland Basin which are obscured by the alluvium.
An areal gravity survey of the Portland Basin covering approximately 450 square kilometers was conducted for this study.
Debye–Hückel Theory For Particles Of Arbitrary Electrical Structure, John D. Ramshaw
Debye–Hückel Theory For Particles Of Arbitrary Electrical Structure, John D. Ramshaw
Physics Faculty Publications and Presentations
Classical linearized Debye–Hückel theory is formulated for a finite fluid system, of arbitrary shape, composed of rigid particles with arbitrary internal electrical structure. The multipole description is eschewed in favor of the more basic description of a particle in terms of its charge density function. This function is left arbitrary, so the particles may be charged or neutral, polar or nonpolar, etc. The theory implies that the direct correlation function c(12)=−v(12)/k T, where v(12) is the Coulomb interaction energy between the charge densities of particles 1 and 2. In the case of uncharged polar …
Pressure Dependence Of Fluorescent And Photolytic Interferences In Ho Detection By Laser-Excited Fluorescence, Thomas M. Hard, Robert J. O'Brien, T. B. Cook
Pressure Dependence Of Fluorescent And Photolytic Interferences In Ho Detection By Laser-Excited Fluorescence, Thomas M. Hard, Robert J. O'Brien, T. B. Cook
Chemistry Faculty Publications and Presentations
In the measurement of HO concentrations by laser-excited fluorescence, expansion of the sampled air offers a way to reduce fluorescent and photolytic interference by other species. The decrease in [HO] upon expansion is balanced by an increase in HO fluorescence yield over a wide range of pressures. Background air fluorescence is reduced if the responsible species have fluorescence yields higher than those of HO. Preliminary experiments indicate that most of the fluorescence observed in laboratory air is due to such species. Upon expansion, the suppression of fluorescent interference can be no greater than the reduction in pressure, whereas the suppression …
Effective Force Constant Ratios: Iron In Iridium And Rhodium, Dennis Munsterman
Effective Force Constant Ratios: Iron In Iridium And Rhodium, Dennis Munsterman
Dissertations and Theses
Classical methods of analyzing heat capacity data for the characteristic moments of the frequency distribution are applied to iridium and rhodium. Impurity moments are determined from high and low temperature f values. These moments are combined by modern theory to estimate the magnitude of the host-host to host-impurity force constant ratio. Ratios of the various host moments are also examined.
Partial Chemical Equilibrium In Fluid Dynamics, John D. Ramshaw
Partial Chemical Equilibrium In Fluid Dynamics, John D. Ramshaw
Physics Faculty Publications and Presentations
An analysis is given for the flow of a multicomponent fluid in which an arbitrary number of chemical reactions may occur, some of which are in equilibrium while the others proceed kinetically. The primitive equations describing this situation are inconvenient to use because the progress rates ω [subscript s] for the equilibrium reactions are determined implicitly by the associated equilibrium constraint conditions. Two alternative equivalent equation systems that are more pleasant to deal with are derived. In the first system, the ω [subscript s] are eliminated by replacing the transport equations for the chemical species involved in the equilibrium reactions …
Geology Of The Southcentral Margin Of The Tillamook Highlands; Southwest Quarter Of The Enright Quadrangle, Tillamook County, Oregon, Kenneth Allan Cameron
Geology Of The Southcentral Margin Of The Tillamook Highlands; Southwest Quarter Of The Enright Quadrangle, Tillamook County, Oregon, Kenneth Allan Cameron
Dissertations and Theses
The Tillamook Highlands is a largely unmapped volcanic pile located in the north end of the Coast Range of Oregon. The 36 square miles of T. 1 N., R. 8 W., on the southcentral margin of the Highlands, was chosen for detailed study.
The study area is composed of Eocene age sedimentary and volcanic units which were deposited in a filling basin. The lowest units were deposited in moderate to deep marine waters; the uppermost were deposited subaerially.