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Theses/Dissertations

1992

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Articles 271 - 300 of 347

Full-Text Articles in Physical Sciences and Mathematics

Studies Of Ecological Factors That Affect The Population And Distribution Of The Western Gray Squirrel In Northcentral Oregon, Susan Ann Foster Jan 1992

Studies Of Ecological Factors That Affect The Population And Distribution Of The Western Gray Squirrel In Northcentral Oregon, Susan Ann Foster

Dissertations and Theses

The western gray squirrel (Sciurus griseus griseus Ord) occur only in the Pacific states and in a small corner of extreme western Nevada. Field studies of aspects of the ecology of the most widely distributed subspecies of western gray squirrel (S. griseus) were conducted at three sites in the ponderosa pine-Oregon white oak zone on the eastern slopes of Mt. Hood, Wasco County, Oregon, between 1981 and 1989. From 1981 through 1987, a Hunter Cooperation Program provided remains of squirrels shot during the annual late summer-early autumn hunting season. Other data were gathered through capture and release studies, radiotelemetry, and …


Remote Dianions In The Synthesis Of Indolizidine Alkaloids, Diana L. C. Green Green Jan 1992

Remote Dianions In The Synthesis Of Indolizidine Alkaloids, Diana L. C. Green Green

Dissertations

No abstract provided.


Syntheses Of Azure-B Neuropeptide Conjugates And A Novel Bicyclic Triene, Milind D. Choubal Jan 1992

Syntheses Of Azure-B Neuropeptide Conjugates And A Novel Bicyclic Triene, Milind D. Choubal

Dissertations

No abstract provided.


The Application Of Liquid Junctions For Characterization Of Semiconductor Materials, Wu-Mian Shen Jan 1992

The Application Of Liquid Junctions For Characterization Of Semiconductor Materials, Wu-Mian Shen

Dissertations, Theses, and Capstone Projects

In this study, liquid junctions were used to characterize silicon and silicon subjected to various reactive ion etching (RIE); surface optimization of CuInSe{dollar}\sb2{dollar}; and photo-modification of InSe. Impedance spectroscopy and modulation spectroscopies such as electrolyte electroreflectance (EER), photoreflectance (PR), and photoreflectance in the presence of electrolyte (EPR) were the major methodologies that were used for investigating the dielectric properties of the semiconductors and their interface with the ambients. It was shown that the above experimental techniques provide information about the flat-band potential, doping density, Fermi level pinning, the density and distribution of surface states, energy gap and broadening parameter related …


The Stratigraphy And Sedimentology Of The Sentinel Butte Formation (Paleocene) In South-Central Williams County, North Dakota, Wesley D. Peck Jan 1992

The Stratigraphy And Sedimentology Of The Sentinel Butte Formation (Paleocene) In South-Central Williams County, North Dakota, Wesley D. Peck

Theses and Dissertations

Approximately 163 meters (535 feet) of the Paleocene Sentinel Butte Formation crop out in southcentral Williams county, North Dakota. To determine their mode of deposition and stratigraphic position within the formation, twelve stratigraphic sections were measured. These strata were deposited in alternating fluvial and lacustrine environments as determined by sedimentary structures, lithology, lithologic sequences, and fossil occurrences. A fining upward trend in grain size of the tabular sandstones, and the identification of epsilon cross-stratification in the tabular sandstones support a fluvial origin for some of the strata. The strongest evidence for the interpretation of lacustrine deposition is the presence of …


Effect Of Sinkholes On Soil Moisture And Ground Water Recharge At An Abandoned Underground Coal Mine Near Wilton, North Dakota, Michael M. Sonderman Jan 1992

Effect Of Sinkholes On Soil Moisture And Ground Water Recharge At An Abandoned Underground Coal Mine Near Wilton, North Dakota, Michael M. Sonderman

Theses and Dissertations

Subsidence at abandoned underground mines in south-central and southwest North Dakota has produced numerous sinkholes. Previous studies in the Northern Great Plains have suggested depression-focused recharge may be a significant ground water recharge mechanism in this region. Thus, sinkholes may increase soil moisture and ground water recharge. Current reclamation practices include filling sinkholes with non-topsoil fill material. However, the benefits of increases in soil moisture and ground water supplies may outweigh the benefits of expensive reclamation. The purpose of this study was to determine whether soil moisture and, hence, the potential for ground water recharge, was greater in sinkholes than …


Introduction To Fractal Geometry: Definition, Concept, And Applications, Mary Bond Jan 1992

Introduction To Fractal Geometry: Definition, Concept, And Applications, Mary Bond

Presidential Scholars Theses (1990 – 2006)

It has become evident that fractals are not to be tied down to one compact, Webster-style, paragraph definition. The foremost qualities of fractals include self-similarity and dimensionality. One cannot help but appreciate the aesthetic beauty of computer generated fractal art. Beyond these characteristics, when trying to grasp the idea of fractal geometry, it is helpful to learn about its many applications. Fractal geometry is opening new doors for study and understanding in diverse areas such as science, art, and music. All of these facets of fractal geometry unite to provide an intriguing, and alluring, wardrobe for mathematics to wear, so …


Preparation Of Electron Donor And Acceptor Molecules For Porphyrin Derivatization, Christoph Hoefler Jan 1992

Preparation Of Electron Donor And Acceptor Molecules For Porphyrin Derivatization, Christoph Hoefler

Dissertations and Theses

Porphyrins derivatized with electron donating and electron withdrawing groups can be used for artificial photosynthesis. Four new compounds, two electron donors and two electron acceptors, have been synthesized for prospective porphyrin linkages.


Regional Tectonic Deformation Of The Northern Oregon Coast As Recorded By Pleistocene Marine Terraces, Richard Alan Mulder Jan 1992

Regional Tectonic Deformation Of The Northern Oregon Coast As Recorded By Pleistocene Marine Terraces, Richard Alan Mulder

Dissertations and Theses

Pleistocene marine terraces of the northern Oregon coast are an important factor in understanding the tectonics and paleoseismicity of the central Cascadia subduction zone. The lowest marine terrace, tentatively correlated to 80,000 year old Whiskey Run terrace of southern Oregon, is intermittently exposed in the present day sea cliff along an 80 km section of coastline between Tillamook Head and Cape Kiwanda. Terrace sediments consist largely of fine material such as clay, silt and fine sand with several locations containing large amounts of gravel derived from nearby headlands and steep bedrock hills. The terrace sediments are interpreted to be deposited …


The Group Spreadsheet, George Francis Morrissey Jr. Jan 1992

The Group Spreadsheet, George Francis Morrissey Jr.

UNF Graduate Theses and Dissertations

Groupware is fast becoming an important part of the computing world. This thesis reviews past history and research in which a group oriented spreadsheet is shown to have a real purpose in today's business world. A group oriented spreadsheet was implemented using a public domain package called The Spreadsheet Calculator. Spreadsheet users and programmers tested the implementation. The results and conclusions of this implementation are also presented.


Global Domination Of Factors Of A Graph, Julie R. Carrington Jan 1992

Global Domination Of Factors Of A Graph, Julie R. Carrington

Retrospective Theses and Dissertations

A factoring of a graph G = (V, E) is a collection of spanning subgraphs F1, F2, ... , Fk, known as factors into which the edge set E has been partitioned. A dominating set of a graph is a set of nodes such that every node in the graph is either contained in the set or has an edge to some node in the set. Each factor Fi is itself a graph and so has a dominating set. This set is called a local dominating set or LDS. An LDS of minimum …


Denitrification In The Elk Valley Aquifer, Northeastern North Dakota, Gale G. Mayer Jan 1992

Denitrification In The Elk Valley Aquifer, Northeastern North Dakota, Gale G. Mayer

Theses and Dissertations

Biological denitrification controls nitrate distribution in the Elk Valley aquifer, which underlies approximately 725 square kilometres of northeastern North Dakota and provides drinking water for farms and rural communities in the area. Increased irrigation has raised concerns over potential contamination from agricultural practices. The purpose of this study was to establish the role of biological denitrification in minimizing concentration and distribution of nitrate and to determine the effect irrigation practices have on groundwater flow and nitrate distribution in the saturated zone.

The aquifer is unconfined and consists of up to 20 metres of glacial outwash and deltaic shale-rich sand deposits. …


Hydrogeologic Characterization Of A Discharge Wetland In Northeastern Grand Forks County, North Dakota, Dean R. Goebel Jan 1992

Hydrogeologic Characterization Of A Discharge Wetland In Northeastern Grand Forks County, North Dakota, Dean R. Goebel

Theses and Dissertations

Soil salinization associated with saline groundwater discharge results in decreased agricultural production in the central glacial Lake Agassiz plain of North Dakota. Saline discharge occurs in a belt of ephemeral wetlands in the lake plain. The physical and chemical hydrology of .the Lunby-stewart saline discharge wetland were investigated in order to provide information which could facilitate land management strategies applicable to this and other discharge wetlands.

Hydrologic data used to characterize the wetland were obtained from monitoring wells, staff gages, precipitation gages, borings, and earth electrical resistivity soundings. Temporal and spatial variations were observed in the water table, the vertical …


Developing A Guidebook For An Outdoor Classroom, David D. Martell Jan 1992

Developing A Guidebook For An Outdoor Classroom, David D. Martell

Theses Digitization Project

Field guide -- Map -- Nature trail plant species -- Plant identification key -- Species test plot -- Climate -- Cloud identification -- Desert soils -- Tortoise station -- Animal track and pond.


Mountain Habitat Activity Guide, Gina Glock Jan 1992

Mountain Habitat Activity Guide, Gina Glock

Theses Digitization Project

No abstract provided.


An Investigation Of Ibm Pc Computer Viruses Infection Rates And Types In A Western Australian Environment, Boon Guan Lee Jan 1992

An Investigation Of Ibm Pc Computer Viruses Infection Rates And Types In A Western Australian Environment, Boon Guan Lee

Theses : Honours

In recent years computer viruses have become increasingly significant as a form of computer abuse. By virtue of their reproductive capability, computer viruses can have cumulative and potentially catastrophic effects to the many people who use those affected computers. There is a growing concern in the computing community about these forms of electronic vandalism. This concern arises from the possible damage to stored information on which the work depends and the ensuing disruption of the work-place. Although the vandalism or purposeful abuse by introducing computer viruses to computer systems was originally mainly an American experience, research reports published by the …


K Dimension Continued Fractions And K Dimension Golden Ratios, Tascha Gwyn Yoder Jan 1992

K Dimension Continued Fractions And K Dimension Golden Ratios, Tascha Gwyn Yoder

Presidential Scholars Theses (1990 – 2006)

The following is an investigation dealing with continued fractions based on research conducted by Professor John C. Longnecker at the University of Northern Iowa.


Nonlinear Dynamics In Oscillating Waterfalls, Michael Schumann Jan 1992

Nonlinear Dynamics In Oscillating Waterfalls, Michael Schumann

Dissertations and Theses

The concern of this thesis was to investigate the nonlinear dynamics inherent in oscillating waterfalls.


Adsorption Of Halogenated Phenolate Ions To Egg-Phosphatidylcholine Vesicles, Andreas Blochel Jan 1992

Adsorption Of Halogenated Phenolate Ions To Egg-Phosphatidylcholine Vesicles, Andreas Blochel

Dissertations and Theses

In this study, parameters for the adsorption of several halogenated phenolate ions to egg-phosphatidylcholine vesicles have been determined by microelectrophoresis.


Stratigraphy And Structure Of The Southeast Part Of The Portland Basin, Oregon, Kenneth E. Lite Jr. Jan 1992

Stratigraphy And Structure Of The Southeast Part Of The Portland Basin, Oregon, Kenneth E. Lite Jr.

Dissertations and Theses

The southeast part of the Portland Basin has been previously described by other investigators. However, little detailed information existed on the depositional relationships between the units, the various sedimentary fades, or the origin of many of the units.


Land Use And Wetland Function: A Sensitivity Analysis Of The Vims Nontidal Wetland Functional Assessment Method, Martha Craig Jan 1992

Land Use And Wetland Function: A Sensitivity Analysis Of The Vims Nontidal Wetland Functional Assessment Method, Martha Craig

Dissertations, Theses, and Masters Projects

No abstract provided.


Taxonomy Of Larval Blennioidei Of Belize, Central America, Martin Ray Cavalluzzi Jan 1992

Taxonomy Of Larval Blennioidei Of Belize, Central America, Martin Ray Cavalluzzi

Dissertations, Theses, and Masters Projects

No abstract provided.


Mineralogy, Geochemistry, And Dispersal Of Opaque Oxides On The Continental Shelf Of The Cascadia Margin, Kommajosyula Subramanya Ravi Jan 1992

Mineralogy, Geochemistry, And Dispersal Of Opaque Oxides On The Continental Shelf Of The Cascadia Margin, Kommajosyula Subramanya Ravi

Dissertations and Theses

Opaque oxide minerals (ilmenite, chromite, and magnetite) in sands from the Oregon continental shelf have been studied to establish the provenance, dispersal, and grade of potential shelf placer deposits. The study area extends southward from offshore of the Columbia River in northern Oregon to the Klamath River in northern California.


Regression Trees Versus Stepwise Regression, Mary Christine Jacobs Jan 1992

Regression Trees Versus Stepwise Regression, Mary Christine Jacobs

UNF Graduate Theses and Dissertations

Many methods have been developed to determine the "appropriate" subset of independent variables in a multiple variable problem. Some of the methods are application specific while others have a wide range of uses. This study compares two such methods, Regression Trees and Stepwise Regression. A simulation using a known distribution is used for the comparison. In 699 out of 742 cases the Regression Tree method gave better predictors than the Stepwise Regression procedure.


A Study Of The Summer Steelhead, Oncorhynchus Mykiss In Several Intermittent Tributaries Of The Satus Creek Basin, Washington, Joel Denney Hubble Jan 1992

A Study Of The Summer Steelhead, Oncorhynchus Mykiss In Several Intermittent Tributaries Of The Satus Creek Basin, Washington, Joel Denney Hubble

All Master's Theses

The summer steelhead, Oncorhynchus mykiss population was studied in three intermittent tributaries in the Satus Creek Basin. There was a strong tendency for post emergent fry, resulting from redds located in intermittent reaches to move downstream. However, survival to perennial flow conditions was very low. Steelhead production in Dry Creek appears to be lower than in Logy Creek, because of elevated water temperatures and minimal spring and summer stream flow.


Butenolide Synthesis Via Cation-Initiated Ring Expansion/Elimination Of Β-Lactones, Jianhua Huang Jan 1992

Butenolide Synthesis Via Cation-Initiated Ring Expansion/Elimination Of Β-Lactones, Jianhua Huang

Masters Theses

An area of recent research in the Black research group is an exploration of the potential of cation-initiated β-lactone ring expansions, accompanied by the elimination of a proton or other electrofuge, as a protocol for the synthesis of multisubstituted butenolides.

Γ-Bromo β-lactones were prepared via bromolactonization of the appropriate β,Γ-unsaturated acids under basic conditions. The nucleofugal bromine atom on the Γ-carbon was then employed to effect carbocation formation adjacent to the lactone ring oxygen atom; the most efficacious reagent combination was found to be silver nitrate in refluxing acetic acid. Generation of this cation initiated a migration of the β-lactone …


The Effects Of Beaver-Created Wetlands On Surface Water Quality Of Streams And Rivers In Dupage County, Illinois, Brian Conklin Jan 1992

The Effects Of Beaver-Created Wetlands On Surface Water Quality Of Streams And Rivers In Dupage County, Illinois, Brian Conklin

Masters Theses

Dam construction by beavers creates wetlands which have the potential to improve water quality, especially in areas near urban centers. However, beaver dams may also cause flooding problems which can result in the removal of the beaver(s) and the destruction of their dam. A further understanding of how beaver-created wetlands affect water quality will provide additional data which can be utilized in beaver management decisions.

In this study, 41 chemical parameters were examined from water taken above and below beaver-created wetlands that existed in DuPage County, Illinois between May and September 1991. This study was designed to examine the effects …


The First Documentation Of A Lower Middle Pennsylvanian Upland Flora From The Eastern Margin Of The Eastern Interior Basin (Illinois Basin), Vicki J. Comer Jan 1992

The First Documentation Of A Lower Middle Pennsylvanian Upland Flora From The Eastern Margin Of The Eastern Interior Basin (Illinois Basin), Vicki J. Comer

Masters Theses

The primary objective of this study is to reconstruct the paleofloristics of an unnamed shale of lower Middle Pennsylvanian age. The shale is periodically exposed in the highwall of the Ashboro Pit, Log Cabin Coal Company, Clay County, Indiana. This will be the first upland fossil flora to be described from the eastern margin of the Eastern Interior Basin (Illinois Basin). The gray shale containing the upland flora lies directly above the Upper Block Coal (SW 1/4, SE 1/4, sec. 17, T. 11N., R. 6W.)

Two collections, collected on three different occasions were made available for analysis: Smithsonian Natural …


Iron Tricarbonyl Derivatives Of Ditertiary Phosphines, Xi Chen Jan 1992

Iron Tricarbonyl Derivatives Of Ditertiary Phosphines, Xi Chen

Masters Theses

In this work we have explored reactions of coordinated diphenylvinylphosphine with coordinated diphenylphosphine. Starting materials, (OC)4FePPh2CH=CH2, trans- (OC)3Fe(PPh2CH=CH2)2, (OC)4FePPh2H, and trans- (OC)3Fe(PPh2H)2 were successfully prepared from known procedures. The bimetallic complex, (OC)4FePPh2CH2CH2PPh2Fe(CO)4, was obtained in 69% yield from the reaction of ((OC)4FePPh2CH=CH2 with (OC)4FePPh2H. The trimetallic complex, (OC)4FePPh2CH2CH2 …


Studies On Improving The Regioselectivity Of Reactions Of Sucrose: The Role Of Molecular Recognition And Polymer Supported Syntheses, Ran Jiang Jan 1992

Studies On Improving The Regioselectivity Of Reactions Of Sucrose: The Role Of Molecular Recognition And Polymer Supported Syntheses, Ran Jiang

Masters Theses

The world economy is critically dependent upon natural resources. Because sucrose can be inexpensively produced in large quantities and refined to a purity unequalled by almost all other natural products, it has been exploited as an industrial raw material for many years, primarily as a sweetener. A major difficulty in utilizing sucrose as an industrial feedstock is the lack of regioselectivity in synthetic reactions due to its eight hydroxyl groups of similar reactivity.

The long range goal in this work is to apply the technique of molecular recognition by template imprinting to the creation of a material that will bind …