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Articles 3601 - 3630 of 3797
Full-Text Articles in Physical Sciences and Mathematics
High Valent Chromium (V) And Chromium (Vi) Complexes, Harry Bennett Davis
High Valent Chromium (V) And Chromium (Vi) Complexes, Harry Bennett Davis
Dissertations and Theses
A new preparative route to the only neutral chromium (V) oxide fluoride, chromium oxide trifluoride, has been accomplished by the reaction of xenon difluoride with chromyl fluoride at high temperature. The chromium oxide trifluoride is produced as crystals which are suitable for single crystal studies. In reactions of chromium oxide trifluoride with alkali and alkaline metal fluorides in anhydrous hydrogen fluoride, new chromium(V) oxide fluoride salts were obtained; these salts were not of high purity due to unknown problems. An attempt to prepare chromium oxide tetrafluoride by the reaction of xenon difluoride with chromyl fluoride in anhydrous hydrogen fluoride failed …
Stratigraphy And Sedimentology Of Paleogene Arkosic And Volcaniclastic Strata, Johnson Creek-Chambers Creek Area, Southern Cascade Range, Washington, Warren Jon Winters
Stratigraphy And Sedimentology Of Paleogene Arkosic And Volcaniclastic Strata, Johnson Creek-Chambers Creek Area, Southern Cascade Range, Washington, Warren Jon Winters
Dissertations and Theses
Over 1150 m of middle to late Eocene nonmarine arkose, lithic arkose, mudstone, and siltstone, referred to here as the Chambers Creek beds, are int~r.stratified with, and overlain by over 1600 m of late Eocene-Oligocsne(?) andesitic volcaniclastic and subordinate volcanic rocks assigned to the Ohanapecosh Formation, in a dissected structural high in the southern Washington Cascade Range, about 18 km south-southeast of the town of Packwood.
Quaternary Volcanology Of The West Crater-Soda Peaks Area, Southern Washington Cascade Range, David R. Polivka
Quaternary Volcanology Of The West Crater-Soda Peaks Area, Southern Washington Cascade Range, David R. Polivka
Dissertations and Theses
The West Crater-Soda Peaks area covering about 100 km is located 35 km southeast of Mount St. Helens in southern Washington State. It is one of several Quaternary monogenetic High Cascade volcanic centers overlying the Ohaaapecosh Formation of the Western Cascade Group and interstratified glacial till.These volcanic centers are the most westerly of the range.
A Theoretical And Experimental Examination Of Sodium Chloride Hydration, Debra Conway Modra
A Theoretical And Experimental Examination Of Sodium Chloride Hydration, Debra Conway Modra
Dissertations and Theses
A Hitachi Hu 125C transmission electron microscope in which the standard specimen holder was replaced by an environmental cell was used to observe the hydration of sodium chloride crystals. To observe Kelvin curvature and solubility effects sodium chloride crystals which were 0.1u or smaller were of special interest. An electrohome video system attached to the electron microscope was used to record the sodium chloride hydration for subsequent particle measurement and viewing.
A theoretical model was also developed. Thermodynamic properties such as the Kelvin curvature and solubility effects were considered as well as the kinetic expressions for salt dissolution/recrystalization and water …
Ionization Of Heavy Atoms By Polarized Relativistic Protons, P.T. Leung, M. L. Rustgi
Ionization Of Heavy Atoms By Polarized Relativistic Protons, P.T. Leung, M. L. Rustgi
Physics Faculty Publications and Presentations
The effect due to the polarization of the incident high-energy (~GeV) proton beam on the ionization cross section of heavy atoms is investigated. In particular, with the use of Darwin wave functions for the atomic electron, the effect for hydrogenlike atoms is worked out. A numerical illustration shows that the polarization effect is completely insignificant. The authors also conclude that the K-shell ionization process is completely insensitive to the polarization of the incident beam.
The Application Of Exact Electrodiffusion Theory To Ion Transport Across Lipid Bilayer Membranes, Scott Cohen
The Application Of Exact Electrodiffusion Theory To Ion Transport Across Lipid Bilayer Membranes, Scott Cohen
Dissertations and Theses
The question of how ions interact with each other and with the potential energy barrier in thin lipid bilayer membranes has interested investigators for several years. The application of electrodiffusion theory to the study of this question is the central theme of this work. We have calculated current-voltage curves for barriers of various shapes and heights, in each case by means of numerically integrating the exact electrodiffusion equation as well as this same equation in the constant field approximation. We have also calculated the total charge in the membrane for the same conditions under which we have calculated the current-voltage …
Generalized Response Of Chemiluminescence Analyzers, A. A. Mehrabzadeh, Robert J. O'Brien, Thomas M. Hard
Generalized Response Of Chemiluminescence Analyzers, A. A. Mehrabzadeh, Robert J. O'Brien, Thomas M. Hard
Chemistry Faculty Publications and Presentations
The mass flow and chemical kinetic equations for a gaseous chemiluminescence (CL) analyzer are formulated and solved. The resultant equation can be used to predict the absolute response of the analyzer as a function of the sample flow rate, the sample gas pressure, the chamber pressure, the chamber volume, the mass flow rate and mole fraction of the reagent gas, and the rate constants of the relevant chemical processes. Thus, the equation allows optimization of these parameters. It is shown that for varying sample pressure the analyzer can be used to measure either concentration or mole fraction and that interfering …
Derivation And Test Of Predictions Of A Discrete Latent State Model For Signed Number Addition Test Performance, Kentaro Yamamoto
Derivation And Test Of Predictions Of A Discrete Latent State Model For Signed Number Addition Test Performance, Kentaro Yamamoto
Dissertations and Theses
This study is an investigation of the performance of a discrete latent state model devised by Paulson (1982) to account for signed-number arithmetic test data gathered by Birenbaum and Tatsuoka (1980). One hundred twenty nine students took a test which consists of sixteen item types with four parallel arithmetic items of each type. The present study utilizes the five addition item types of four items each; hence, there are four parallel subtests. Responses to the addition items can be analyzed in terms of two components: the sign component (is the sign correct?), and the absolute value component (is the size …
Depositional Model Of The Antelope Coal Field, Wyoming, Christine M. Budai
Depositional Model Of The Antelope Coal Field, Wyoming, Christine M. Budai
Dissertations and Theses
The coal-bearing sediments of the Antelope coal field in the southcentral Powder River Basin, Wyoming were deposited in paludal and tributary subsystems of the fluvial system that existed in the basin during the early Tertiary. A depositional model for the Antelope coal field was constructed from data collected from approximately 500 drill holes that penetrated the upper 90 meters (300 feet) of the Fort Union Formation. The depositional environments were interpreted from lithologic descriptions and guidelines established in the literature.
The two main coal seams at the Antelope coal field are the Anderson and stratigraphically lower Canyon coal seams. They …
The Combined Effect Of Cu And Zn On Selenastrum Capricornutum, Helmer Colonia-Roque
The Combined Effect Of Cu And Zn On Selenastrum Capricornutum, Helmer Colonia-Roque
Dissertations and Theses
It has been demonstrated that the toxicity of heavy metals depends on their chemical speciation and can be related to their free ion activities, rather than the total metal concentrations. The objective of this study was to determine the effect of combined free ions of zinc and copper on the toxicity to the green alga Selenastrum capricornutum. This alga was grown in a defined medium, under controlled laboratory conditions, with a varying range of zinc and copper concentrations. The growth rate of the alga was inhibited at pZn = 5.93 or at pCu = 7.24. The results suggest that …
The Effects Of Various Chemical Treatments On The Surface Area Of Coals, Maria Margaret Ludvig
The Effects Of Various Chemical Treatments On The Surface Area Of Coals, Maria Margaret Ludvig
Dissertations and Theses
Surface areas of most American coals are small when measured by N2 adsorption at 77 K and large when measured by CO2 adsorption at 298 K, implying that the majority of the pores are less than 5 Å in diameter. This small pore size would restrict many gaseous and liquid reactants from entering the internal pore system of the coal, and hence, reduces the efficiency of coal conversion. Therefore, if the surface area, as measured by N2 (77 K), could be increased, that is, to increase the pore size, the conversion of coal into useful products should …
Formation And Zonation Of Ferruginous Bauxite Deposits Of The Chapman Quadrangle, Oregon, Richard Charles Marty
Formation And Zonation Of Ferruginous Bauxite Deposits Of The Chapman Quadrangle, Oregon, Richard Charles Marty
Dissertations and Theses
Two major theories have been advanced to account for the scattered distribution of ferruginous bauxite deposits. Original workers proposed that ferruginous bauxite originally developed over all exposed Columbia River Basalt in western Oregon and was subsequently removed by erosion. Studies which followed have suggested that it may be locally favorable conditions, especially of drainage, which are responsible for deposit distribution. Field mapping in the Chapman Quadrangle shows a possible correlation between a series of sheared zones, which may have improved drainage, and the distribution of ferruginous bauxite deposits. Examination of the pisolitic zone ferruginous bauxite of the Chapman Quadrangle failed …
Stratigraphic Relationships Of The Tillamook Volcanics And The Cowlitz Formation In The Upper Nehalem River-Wolf Creek Area, Northwestern Oregon, Michael Keith Jackson
Stratigraphic Relationships Of The Tillamook Volcanics And The Cowlitz Formation In The Upper Nehalem River-Wolf Creek Area, Northwestern Oregon, Michael Keith Jackson
Dissertations and Theses
The upper Nehalem River-Wolf Creek area is located on the northeastern flank of the Tillamook Highlands in the northern Oregon Coast Range. Three rock stratigraphic units underlie the thesis area, and these units range from late Eocene to Oligocene in age.
Stopping Power Of K Electrons At Extreme Relativistic Energies, P.T. Leung, M. L. Rustgi
Stopping Power Of K Electrons At Extreme Relativistic Energies, P.T. Leung, M. L. Rustgi
Physics Faculty Publications and Presentations
The recent work of Anholt (1979) on K-vacancy production by relativistic projectiles has been applied to calculate the stopping power of the K electrons. The results show that for protons of energy ~10³ GeV and heavy target elements, the relativistic contributions to the stopping power amount to several times the results due to the longitudinal terms obtained from Walske's (1956) work.
Holocene Geologic History Of The Clatsop Plains Foredune Ridge Complex, David Karl Rankin
Holocene Geologic History Of The Clatsop Plains Foredune Ridge Complex, David Karl Rankin
Dissertations and Theses
This research formulated a recent geologic history of the Clatsop Plains dating from 3500 years BP to present. Research consisted of geomorphic mapping, near-surface stratigraphic evaluation, carbon dating and subsurface interpretation of available data.
Geophysical Strain And Tilt : Measurement Methodology And Analysis Of Data, Robert Mackay
Geophysical Strain And Tilt : Measurement Methodology And Analysis Of Data, Robert Mackay
Dissertations and Theses
Tilt and strain meters were installed on the Portland State University campus in the summer of 1982 and data was collected for 4 months. Instrument selection, operation, installation and performance are discussed.
Suggestions that could enhance data quality and data collection efficiency are presented.
An analysis procedure is suggested and an example of this procedure for an interval of data is discussed. The influence of the temperature, pressure, rainfall and solid earth tides on the signal is investigated, as well as the correlation between similar channels of the different tilt instruments. The temperature, rainfall and solid earth tides were all …
A Study Of The Diagenesis Of The Overburden Between The Badger And School Coal Seams, Dave Johnston Coal Field, Converse County, Wyoming, Rebecca K. Jaffer
A Study Of The Diagenesis Of The Overburden Between The Badger And School Coal Seams, Dave Johnston Coal Field, Converse County, Wyoming, Rebecca K. Jaffer
Dissertations and Theses
Low pH zones in portions of the overburden at the Dave Johnston Coal Field, Converse County, Wyoming are the subject of this study. The low pH zones are restricted to limonite stained sandstones which grade downdip into normal pH gray sandstones. Changes in color, clay mineralogy, cementation and feldspar surface textures are noted between the two sandstone units. These changes appear to be the result of post depositional alteration that was responsible for oxidation of pyrite and chlorite, dissoluion of calcite, and the etching of feldspar grains. The parameters for the diagenesis fit those of uranium roll front models proposed …
Structural Effects On K-Vacancy Production By Protons Of Extreme Relativistic Energies, P.T. Leung, M. L. Rustgi
Structural Effects On K-Vacancy Production By Protons Of Extreme Relativistic Energies, P.T. Leung, M. L. Rustgi
Physics Faculty Publications and Presentations
The effect on the K-vacancy-production cross section due to the finite distribution of charge and magnetic moment of the incident proton is examined. Numerical results are given for two target elements, namely, Ni and U. The results show that even at energy as high as 10³ GeV the incident proton can still be regarded as a point charge. The effect on the stopping power of matter is discussed.
Effects On Electrolytic Cells Of Magnetic Fields Applied To Single Electrodes, Craig Allen Cousins
Effects On Electrolytic Cells Of Magnetic Fields Applied To Single Electrodes, Craig Allen Cousins
Dissertations and Theses
The primary goal of this research was to investigate the effects associated with the application of magnetic fields to single electrodes.
Geology And Hydrothermal Alteration, Glass Buttes, Southeast Oregon, Dulcy Annette Berri
Geology And Hydrothermal Alteration, Glass Buttes, Southeast Oregon, Dulcy Annette Berri
Dissertations and Theses
The Glass Buttes volcanic complex consists of many domes and individual vents that erupted both rhyolitic and basaltic lavas during the late Miocene to early Pliocene. The east half of the complex, in the vicinity of Little Glass Butte, contains interfingering, finely flow-banded rhyolite and black obsidian flows. The youngest unit, an obsidian, has been dated at 4.9 m.y. East of Little Glass Butte lie two northwest-trending ridges, Antelope and Cascade Ridges, composed of two or more overlapping exogenous domes that formed along northwest-trending faults.
Massless Neutrinos And The Stellar Stopping Power Via The V-A And Weinberg Interactions, P.T. Leung, M. L. Rustgi
Massless Neutrinos And The Stellar Stopping Power Via The V-A And Weinberg Interactions, P.T. Leung, M. L. Rustgi
Physics Faculty Publications and Presentations
A formula for the stopping power of matter for neutrinos and antineutrinos, interacting with electrons via the weak interaction in the context of both the V-A theory and the Weinberg theory is derived in the high-Q approximation and applied to study the solar-neutrino anomaly. The result shows that neutrinos extending in energy from 1 to 10 MeV produced inside the Sun escape it essentially without any loss of energy. In agreement with previous investigators, Rustgi, Leung, Turner, and Brandt (1981). It is found that the neutrinos should retain the energy given them at their creation essentially forever and permeate the …
Comparison Of Bethe's Formula For Magnetic-Moment Transitions In Atoms With The Generalized Rosenbluth's Equation, P.T. Leung, M. L. Rustgi, J. E. Turner
Comparison Of Bethe's Formula For Magnetic-Moment Transitions In Atoms With The Generalized Rosenbluth's Equation, P.T. Leung, M. L. Rustgi, J. E. Turner
Physics Faculty Publications and Presentations
An error in an old but often quoted paper by Bethe (1935) on the cross section for an atomic transition caused by the magnetic moment of the projectile is corrected by comparing it with the generalized Rosenbluth's formula (1950).
A Geochemical Study Of The Rhododendron And Dalles Formations In The Area Of Mount Hood, Oregon, Marshall W. Gannett
A Geochemical Study Of The Rhododendron And Dalles Formations In The Area Of Mount Hood, Oregon, Marshall W. Gannett
Dissertations and Theses
The Miocene Rhododendron and Dalles Formations in the Mount Hood area are accumulations of chiefly pyroclastic andesitic material, largely confined to the Dalles-Mount Hood syncline. These very similar units are geographically separated by overlying andesites including the present Mount Hood cone, and past workers have suspected that they may share a common source. Prior to this study, few geochemical data were available for the Rhododendron and the Dalles Formations, compared to the well studied Columbia River basalts underlying them and the overlying Pliocene andesites. This geochemical study was designed to investigate certain aspects of the Rhododendron and Dalles Formations such …
Dielectric Constant In Fluids Of Classical Deformable Molecules, John D. Ramshaw
Dielectric Constant In Fluids Of Classical Deformable Molecules, John D. Ramshaw
Physics Faculty Publications and Presentations
Classical statistical mechanical description of dielectric fluids is further discussed. Dipole moment correlations of polarizable molecules are discussed.
Structure And Influence Of The Tillamook Uplift On The Stratigraphy Of The Mist Area, Oregon, Moinoddin Murtuzamiya Kadri
Structure And Influence Of The Tillamook Uplift On The Stratigraphy Of The Mist Area, Oregon, Moinoddin Murtuzamiya Kadri
Dissertations and Theses
Fifty three sedimentary samples were analyzed for their minor and trace element concentrations utilizing instrumental neutron activation analysis. Concentrations of Na, K, La, Sm and Sc, and their ratios appear to establish significant trends. The data suggest a major break from a granitic-metamorphic provenance and a volcanic component dominated provenance between the Cowlitz and Keasey Formations respectively. The provenance of the Astoria Formation indicates the presence of flood basalts.
The Stratigraphic Relationships Of The Columbia River Basalt Group In The Lower Columbia River Gorge Of Oregon And Washington, Terry Leo Tolan
The Stratigraphic Relationships Of The Columbia River Basalt Group In The Lower Columbia River Gorge Of Oregon And Washington, Terry Leo Tolan
Dissertations and Theses
The purpose of this study was to produce a detailed geologic map of the CRBG in the western portion of the Columbia River Gorge (fig. 1). The objectives were (1) to identify and delineate the extent of the Priest Rapids Member and Pomona Member intracanyon flows, and (2) to define the relationship of post-CRBG units to the CRBG intracanyon flows.
A Preliminary Investigation Of The Lithological Characteristics Of The Troutdale Formation In Portions Of The Camas, Sandy, Washougal, And Bridal Veil Quadrangles, David Lee Cole
Dissertations and Theses
The study area encompasses a region of about 80 square kilometers, centered about Corbett, Oregon. Sieve analyses suggest that the Troutdale Formation is composed of a conglomerate, a coarse-grained sandstone, and a siltstone lithofacies. Measured sections data show that 56 to 60 percent of the Troutdale Formation's exposures are composed of the conglomerate lithofacies. The coarsegrained sandstone lithofacies makes up 34 to 38 percent, while the siltstone lithofacies makes up only 4 to 8 percent. Pebble count data show that the representation of basalt varies from 69 to 100 percent, with an average of 85 percent, while quartzite varies from …
A Geophysical Study Of The North Scappoose Creek, Alder Creek, Clatskanie River Lineament, Along The Trend Of The Portland Hills Fault, Columbia County, Oregon, Nina Haas
Dissertations and Theses
The Portland Hills fault forms a strong northwest trending lineament along the east side of the Tualatin Mountains. An en echelon lineament follows North Scappoose Creek, Alder Creek, and the Clatskanie River along the same trend, through Columbia County, Oregon. The possibility that this lineament follows a fault or fault zone was investigated in this study. Geophysical methods were used, with seismic refraction, magnetic and gravity lines run perpendicular to the lineament. The seismic refraction models indicate the near surface basalt is broken in many places, with 15 - 30 meters (50 - 100 feet) vertical displacement, down to the …
The Geology Of The Floras Creek Area, Curry County, Oregon, Jon Dudley Bounds
The Geology Of The Floras Creek Area, Curry County, Oregon, Jon Dudley Bounds
Dissertations and Theses
The Floras Creek area, east of the town of Langlois, near the southwest Oregon coast, includes Colebrooke Schist (a klippe of metamorphosed pelitic sediments of Jurassic age), Jurassic Otter Point Formation (a melange complex), and lower the middle Eocene Roseburg and Lookingglass Formations, part of a sandstone-shale sequence occurring more extensively in other areas. The Colebrooke Schist occurs in the south-central part of the area, bounded on the Otter Point and Roseburg. The Lookingglass is exposed as a small (1.5 sq. km) block in the north-north-west part of the area. Two major structural trends are found in the Floras Creek …
Existence Of The Dielectric Constant In Fluids Of Classical Deformable Molecules, John D. Ramshaw
Existence Of The Dielectric Constant In Fluids Of Classical Deformable Molecules, John D. Ramshaw
Physics Faculty Publications and Presentations
The existence of the dielectric constant epsilon is investigated for fluids composed of classical deformable (polarizable) molecules. The development is based upon generalized functional-derivative relations which involve joint distributions in molecular positions r/sub k/ and dipole moments ..mu../sub k/. Sufficient conditions for the existence of epsilon are expressed in terms of the generalized direct correlation function c(12) = c(r/sub 1/, ..mu../sub 1/; r/sub 2/, ..mu../sub 2/). It is found that epsilon exists if -kTc(12) depends only on relative positions and dipole moment directions (in addition to Vertical Bar..mu../sub 1/Vertical Bar and Vertical Bar..mu../sub 2/Vertical Bar), and becomes asymptotic to the …