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Articles 3661 - 3690 of 3797
Full-Text Articles in Physical Sciences and Mathematics
Stratigraphy And Sedimentation Of The Spencer Formation In Yamhill And Washington Counties, Oregon, Fathi Ayoub Al-Azzaby
Stratigraphy And Sedimentation Of The Spencer Formation In Yamhill And Washington Counties, Oregon, Fathi Ayoub Al-Azzaby
Dissertations and Theses
The Spencer Formation in Yamhill and Washington Counties, Oregon, is exposed in a narrow belt 27 km long, from 1/4 to 3 km wide and with a maximum thickness of about 400 m. The formation is composed entirely of sandstone with interbedded thin layers of mudstone in the uppermost member. The sedimentary structure and paleoecology indicate a shallow marine depositional environment. The upper member of the Spencer Formation contains more quartz, plagioclase, and hornblende than does the lower member, but K-feldspar is less than that of the lower member. Shallower water conditions for the deposition of the upper member are …
The Structure And Stratigraphy Of The Columbia River Basalt In The Chehalem Mountains, Oregon, Abdul-Rahman Mohammed Al-Eisa
The Structure And Stratigraphy Of The Columbia River Basalt In The Chehalem Mountains, Oregon, Abdul-Rahman Mohammed Al-Eisa
Dissertations and Theses
The Chehalem Mountains area, encompassing 70 square kilometers, is at the western extent of the Columbia River Basalt Group as mapped in western Oregon. The flows in the study area were identified as belonging to subdivisions of the Columbia River Basalt Group on the basis of physical characteristics and trace element geochemistry. The basalt flows are poorly exposed in the area and weathering is deep and extensive where the flows have been exposed. Where erosion has exposed the underlying marine sedimentary rocks, the basalt has failed in landslides.
A Study Of The Photolysis Of O-Methyl Podocarpinitrile Oxide, Dianne Marie Hunter
A Study Of The Photolysis Of O-Methyl Podocarpinitrile Oxide, Dianne Marie Hunter
Dissertations and Theses
The photolytic reaction of 0-methyl podocarpinitrile oxide to yield the δ-lactam (shown below) was studied under various conditions such as: solvent (hexane, methanol), mercury lamp wattage (lOOW, 450W), filter (Pyrex, Corex, Vycor), and additives (dichloromethane, hexafluorobenzene). The reactions were analyzed with IR, NMR and HPLC. Preparative medium pressure liquid chromatography and TLC were used in the δ-lactam isolation. The conditions resulting in the optimum yield of δ-lactam were determined. The photolytic stability of the δ-lactam under the conditions in which it was formed indicated that it was relatively stable only in hexane.
Surface Area Of Coal As Influenced By Low Temperature Oxidation Processes, Salvador Leon Arredondo
Surface Area Of Coal As Influenced By Low Temperature Oxidation Processes, Salvador Leon Arredondo
Dissertations and Theses
The possibility of increasing the amount of readily accessible surface area by enlarging the 5 A pore was examined via pretreating the PSOC-371 coal with gases such as nitrogen, nitrogen-oxygen, and ozone-oxygen and hydrogen peroxide solutions. Surface areas were obtained from nitrogen adsorption at 77 K and carbon dioxide adsorption at either 298 or 195 K for each sample before and after treatment.
Transport Of Ozone Across An Air/Water Interface Coupled With Aqueous Decomposition, Ahmad Ali Mehrabzadeh
Transport Of Ozone Across An Air/Water Interface Coupled With Aqueous Decomposition, Ahmad Ali Mehrabzadeh
Dissertations and Theses
Photoacoustic spectroscopy was used to analyze the transport of ozone through the air/water interface. Experimental results showed that the ozone transport rate is similar to rates measured for other gases of low solubility and low reactivity. The transport rate increases with increasing pH. The decomposition rate of ozone was studied in solutions. The decomposition rate also depends on the pH of the solution, and in high pHs both the deposition velocity and the decomposition rate constant of ozone have larger values. The value of the deposition velocity (Kd) is 3.7 ± .9 x 10-3 cm/sec and the decomposition rate …
Geophysical And Geochemical Analyses Of Selected Miocene Coastal Basalt Features, Clatsop County, Oregon, Virginia Josette Pfaff
Geophysical And Geochemical Analyses Of Selected Miocene Coastal Basalt Features, Clatsop County, Oregon, Virginia Josette Pfaff
Dissertations and Theses
The proximity of Miocene Columbia River basalts to the "locally-erupted" coastal Miocene basalts in northwestern Oregon, and the compelling similarities between the two groups, suggest that the coastal basalts, rather than being locally erupted, may be the westward extension of plateau basalts derived from eastern Oregon and Washington.
The local-origin hypothesis is based largely on the interpretation of coastal dikes and sills as representing vent areas; however, a complex mechanism, as yet unsatisfactorily defined, would be required to cause the eruption of virtually identical magmas simultaneously from source areas 500 km apart.
This study, therefore, has investigated the coastal basalt …
Effect Of Phenoxy Acids And Their Derivatives On The Ionic Permeability Of Bilayer Lipid Membranes, Malkanthi Paulis Illangasekare
Effect Of Phenoxy Acids And Their Derivatives On The Ionic Permeability Of Bilayer Lipid Membranes, Malkanthi Paulis Illangasekare
Dissertations and Theses
It has been found that the herbicide 2,4-D has the ability to increase the rate of transport of positive ions of several kinds and inhibit the transport of negatively charged tetraphenylborate ions in lipid bilayer membranes. Only the neutral molecules of 2,4-D are transport active. The ionized 2,4-D molecules do not modify the transport of ions, and do not by themselves permeate through lipid membranes. The results suggest that the enhancement of transport of positively charged ions is dominated by the increase of the ion translocation rate constant. It has been shown that membrane transport of negatively charged tetraphenylborate ions …
Rare, Threatened And Endangered Vascular Plants In Oregon: An Interim Report, Jean L. Siddall, Kenton L. Chambers, David H. Wagner
Rare, Threatened And Endangered Vascular Plants In Oregon: An Interim Report, Jean L. Siddall, Kenton L. Chambers, David H. Wagner
Institute for Natural Resources Publications
This report on rare, threatened and endangered vascular plants in Oregon is a basic document in the process of inventorying the state's natural areas * Prerequisite to the orderly establishment of natural preserves for research and conservation in Oregon are (1) a classification of the ecological types, and (2) a listing of the special organisms, which should be represented in a comprehensive system of designated natural areas. The necessary ecological classification was published in the U.S. Forest Service Pacific Northwest Forest and Range Experiment Station document, "Research Natural Area Needs in the Pacific Northwest," by Dyrness et al. (1975). This …
Interference Suppression In Ho Fluorescence Detection, Thomas M. Hard, Robert J. O'Brien, T. B. Cook, G. A. Tsongas
Interference Suppression In Ho Fluorescence Detection, Thomas M. Hard, Robert J. O'Brien, T. B. Cook, G. A. Tsongas
Environmental Science and Management Faculty Publications and Presentations
In this Letter we report preliminary results on a sampling method that greatly reduces the above interferences relative to hydroxyl fluorescence.
Copper Toxicity And Extracellular Release In Selenastrum Capricornutum, Michael Edwin Darling
Copper Toxicity And Extracellular Release In Selenastrum Capricornutum, Michael Edwin Darling
Dissertations and Theses
Copper toxicity was investigated using the green alga, Selenastrum capricornutum. Two major areas were investigated: the forms of copper which are toxic to growth of the alga and factors that can change the concentration of free copper, Cu2+(aq), in the growth medium during the logarithmic growth of the organism. This research has shown that S. capricornutum is sensitive to the free Copper ion, Cu2+(aq), irrespective of the total copper concentration.
Brownian Motion In A Flowing Fluid, John D. Ramshaw
Brownian Motion In A Flowing Fluid, John D. Ramshaw
Physics Faculty Publications and Presentations
A phenomenological theory is developed for Brownian motion in a flowing incompressible fluid. The Brownian particles are regarded as an ideal gas subject to a position- and time-dependent force field that represents interactions with the host fluid. This approach immediately leads to deterministic partial differential equations of motion for the Brownian particles. These equations are then examined in the limit of large friction, in which they imply an expression for the diffusional mass flux of Brownian particles. This expression is a sum of terms representing concentration, forced, thermal, and pressure diffusion. Comparisons are made with earlier work, and with the …
"The Urban Enigma: America's Urban Alternatives", Christopher L. Salter
"The Urban Enigma: America's Urban Alternatives", Christopher L. Salter
Special Collections: Oregon Public Speakers
Presented with Brown, Harrison Scott, "Energy Resources."
"Energy Resources", Harrison Scott Brown
"Energy Resources", Harrison Scott Brown
Special Collections: Oregon Public Speakers
With: Salter, C. L. The urban enigma.
The Geology And Geochemistry Of The North Fork Stock, Northeastern Oregon, David Joseph Matty
The Geology And Geochemistry Of The North Fork Stock, Northeastern Oregon, David Joseph Matty
Dissertations and Theses
The North Fork stock is a composite intrusive body of Late Jurassic-Early Cretaceous age which outcrops in the Blue Mountains of northeastern Oregon. The upper 600 m of the intrusion are exposed over an area of approximately 36 km2 along the canyon walls of the North Fork of the John Day River in Grant and Umatilla counties. The stock intrudes metasediments, metavolcanics, and metagabbros associated with the Permian-Triassic Elkhorn Ridge Argillite. Contact metamorphism of the Elkhorn Ridge Argillite is developed to the hornblende-hornfels facies throughout most of the exposed area of this unit in the study area. The contact …
The Concentration And Speciation Of Sugars In Natural Waters, Minoo Shakerin Sweet
The Concentration And Speciation Of Sugars In Natural Waters, Minoo Shakerin Sweet
Dissertations and Theses
Due to the importance of carbohydrates in biological systems, many efforts have been made to develop a quantitative method for analysis of carbohydrates in natural waters. The low concentrations of dissolved sugars in natural waters require a sensitive analytical method. In this study, gas chromatography of alditol acetate derivatives of sugars was investigated for quantitative and qualitative analysis of individual dissolved sugars in natural waters. The alditol acetate derivatives of sugars give only one derivative for each sugar, yielding qualitative and quantitative results.
The detection limit was 25 nM for each sugar. Because of this very low detection limit, only …
Comments On The Theory Of Dipolar Fluids, John D. Ramshaw
Comments On The Theory Of Dipolar Fluids, John D. Ramshaw
Physics Faculty Publications and Presentations
The theory of dipolar fluids posbulated by Chan, Mitchell and Ninham is commented upon.
Geology Of North Craters Of The Moon National Monument, Idaho, William C. Sidle
Geology Of North Craters Of The Moon National Monument, Idaho, William C. Sidle
Dissertations and Theses
The purpose of the investigation was to map the geology of the north end of Craters of the Moon National Monument and surrounding area. A stratigraphic sequence of Late Paleozoic sedimentary and Tertiary volcanic rocks was compiles and the structures of these rocks and contact relationships with intrusions were delineated. Grade and facies of contact metamorphism were defined. The Snake River Plain basalts were also mapped. The sources of these flows were determined where possible. Preexisting structures and relationships of vents to earlier faulting were explored in ascertaining extensions of the Great Rift Zone into the Pioneer Mountains. Petrographic descriptions …
The Structure And Stratigraphy Of The Columbia River Basalt In The Hood River Valley, Oregon, Susan Timm
The Structure And Stratigraphy Of The Columbia River Basalt In The Hood River Valley, Oregon, Susan Timm
Dissertations and Theses
The Hood River Valley, located 100 kilometers east of Portland, Oregon, is in the transition zone between two geologic provinces--the High Cascades and the Columbia Plateau. The entire valley is probably underlain by Columbia River Basalt, but it crops out only on steep hillsides and in stream valleys. The base of the basalt is not exposed in the thesis area. The basalt is overlain by Pliocene and Quaternary basalt and andesite, volcanic sediments and glacial debris.
The stratigraphy of the Columbia River Basalt is useful in determining the path of the basalt flows into western Oregon, in mapping the structure …
Structural Geology Of The Southeast Quarter Of The Dutchman Butte Quadrangle, Oregon, Gerald Lee Black
Structural Geology Of The Southeast Quarter Of The Dutchman Butte Quadrangle, Oregon, Gerald Lee Black
Dissertations and Theses
Field work in the southeast quarter of the Dutchman ·Butte Quadrangle, which lies within the Klamath Mountains geomorphic province of southwestern Oregon, was completed during the summers of 1973 and 1974. The objectives of the study were fourfold: (1) to produce a geologic map of the southeast quarter of the Dutchman Butte Quadrangle, (2) to determine the nature of the contact between the Dothan and Rogue formations, (3) to construct a stratigraphic column of the Dothan Formation in the area, and (4) to attempt to determine the nature of the deformation occurring in the area.
Stratigraphy And Sedimentary Petrology Of The Northwest Quarter Of The Dutchman Butte Quadrangle, Southwest Oregon, Thomas Edward Koler
Stratigraphy And Sedimentary Petrology Of The Northwest Quarter Of The Dutchman Butte Quadrangle, Southwest Oregon, Thomas Edward Koler
Dissertations and Theses
The study area lies in southwest Douglas County 5 kilometers south from Camas Valley and is accessible by state highway 42. The purpose of the study was to map the geology at a 1:31,250 scale, determine the stratigraphy, study the petrology of the formations, and determine the provenance within a tectonic setting.
The Systhesis And Photolysis Of 1-Phenylcyclohexaneacetic Acid Azide, Jack P. Mourad
The Systhesis And Photolysis Of 1-Phenylcyclohexaneacetic Acid Azide, Jack P. Mourad
Dissertations and Theses
The aim of this research project was to study the possible synthesis of the morphine analog 3-oxo-5-phenylmorphan via the photochemical cyclization of the acyl azide of 1-phenylcyclohexaneacetic acid.
A Polarographic Study Of Fe(Ii) And Fe(Iii) Complexes With Catechol, Wen-Tang Shen
A Polarographic Study Of Fe(Ii) And Fe(Iii) Complexes With Catechol, Wen-Tang Shen
Dissertations and Theses
A study of the anodic polarography of catechol in 0.100 F sodium perchlorate is presented. A new wave is observed in alkaline solutions which is different from the simple oxidation wave of catechol to ortho-quinone observed by previous workers. The importance of buffer materials is discussed and a possible explanation of the new wave is suggested.
A study of the polarography behavior of Fe(II) and Fe(III) in the presence of catechol is reported. In the case of reduction of Fe(III) in the presence of catechol, two steps occur at about -1.5 and -1.8 volts (vs. SCE) at pH higher than …
A Geophysical Definition Of A Klamath Falls Graben Fault, Cynthis Ann Veen
A Geophysical Definition Of A Klamath Falls Graben Fault, Cynthis Ann Veen
Dissertations and Theses
Four geophysical methods, along with well logs and outcrop data, were used in determining the location of a fault situated on the campus of Oregon Institute of Technology, just north of Klamath Falls, Oregon. The fault displaces rocks of the Yonna Formation, of Pliocene age. Wells located northeast of the fault (on the upthrown side) produce cold water, and wells located southwest of the fault (on the downthrown side) produce hot water. The purpose of this investigation was to define the characteristics of the fault exposed behind a large water tank southeast of the OIT campus.
Fuzziness And Catastrophe, Martin Zwick, Daniel Guy Schwartz, George G. Lendaris
Fuzziness And Catastrophe, Martin Zwick, Daniel Guy Schwartz, George G. Lendaris
Systems Science Faculty Publications and Presentations
In a recent short note, Flondor has alluded to a possible linkage of fuzzy set theory and catastrophe theory. We consider several features of catastrophe theory, namely the properties of discontinuous jumps, hysteresis, and divergence in the "cusp catastrophe," and the role of the bias factor in the "butterfly catastrophe," which have affinities to and suggest possible extensions of fuzzy set ideas. Certain functions extensively considered in catastrophe theory lend themselves in some cases to interpretation as membership functions. The use of such functions may be of interest for the characterization of linguistic descriptions which are time-varying and encompass both …
Requisite Variety And The Second Law, Martin Zwick
Requisite Variety And The Second Law, Martin Zwick
Systems Science Faculty Publications and Presentations
Although the Law of Requisite Variety (LRV) speaks directly about entropy (of a set of disturbances to a system, and of the states and effects of a regulator), the relation of Ashby's principle to the Second Law of Thermodynamics does not appear to have been commented on, In this paper, it is shown that, when regulation is viewed as a temporal process, the LRV can be interpreted as a statement of, and, in fact, a consequence of, the Second Law. In essence, the regulator reduces the variety (entropy) of the system being regulated by a compensatory increase of variety (entropy) …
An Assessment Of The Transmission Electron Microscope For The Study Of Aerosol-Gas Interactions: Direct Observations Of Sodium Chloride Hydration Phenomena, Antony David Clarke
An Assessment Of The Transmission Electron Microscope For The Study Of Aerosol-Gas Interactions: Direct Observations Of Sodium Chloride Hydration Phenomena, Antony David Clarke
Dissertations and Theses
An experimental study of solid-gas interactions was made for sodium chloride particles, using a specially fabricated environmental chamber in a transmission electron microscope. It was found that under suitable conditions the hydration and dehydration of these particles could be directly observed and quantitatively measured. Measurements of growth were obtained with a time resolution of one-thirtieth of a second for particles having diameters ranging from 0.02 μm to 1.0 μm.
"Needed Social Innovations (Lecture 2)", John Rader Platt
"Needed Social Innovations (Lecture 2)", John Rader Platt
Special Collections: Oregon Public Speakers
No abstract provided.
"Environmental Simulation And Long-Term Planning", Michael A. Arbib
"Environmental Simulation And Long-Term Planning", Michael A. Arbib
Special Collections: Oregon Public Speakers
With Cooper, W. Ecosystems.
"Toxic Chemicals In The Environment", William E. Cooper
"Toxic Chemicals In The Environment", William E. Cooper
Special Collections: Oregon Public Speakers
Presented and recorded with Arbib, M. A., "Environmental Simulation and Long-Term Planning."
"Ecosystems", William E. Cooper
"Ecosystems", William E. Cooper
Special Collections: Oregon Public Speakers
From a lecture series with M.A. Arbib, "Environmental simulation and long-term planning."