Physical Sciences and Mathematics Commons^™

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

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.

Recoil Distributions In Particle Transfer, James H. Mcguire, Jack C. Straton, W. J. Axmann, T. Ishihara, E. Horsdal

Physics Faculty Publications and Presentations

Classical Thomas peaks in various fast second-order particle transfer processes are quantum mechanically broadened by energy nonconservation in the intermediate states of collision. This quantum broadening is considered in observable velocity distributions of recoil particles.

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 …

Analytically Reduced Form For The Class Of Integrals Containing Multicenter Products Of 1s Hydrogenic Orbitals, Coulomb Or Yukawa Potentials, And Plane Waves, Jack C. Straton

Physics Faculty Publications and Presentations

The class of integrals containing the product of N 1s hydrogenic orbitals and M Coulomb or Yukawa potentials with m plane waves is investigated analytically. The results obtained by Straton (1989) are extended and generalized. It is shown that the dimensionality of the entire class can be reduced from 3m to M+N-1.

Taylor Instability In Ryholite Lava Flows, B. A. Baum, W. B. Krantz, Jonathan H. Fink, R. E. Dickinson

Geology Faculty Publications and Presentations

A refined Taylor instability model is developed to describe the surface morphology of rhyolite lava flows. The effect of the downslope flow of the lava on the structures resulting from the Taylor instability mechanism is considered. Squire's (1933) transformation is developed for this flow in order to extend the results to three-dimensional modes. This permits assessing why ridges thought to arise from the Taylor instability mechanism are preferentially oriented transverse to the direction of lava flow. Measured diapir and ridge spacings for the Little and Big Glass Mountain rhyolite flows in northern California are used in conjunction with the model …

Fourier Transform Of The Multicenter Product Of 1s Hydrogenic Orbitals And Coulomb Or Yukawa Potentials And The Analytically Reduced Form For Subsequent Integrals That Include Plane Waves, Jack C. Straton

Physics Faculty Publications and Presentations

The Fourier transform of the multicenter product of N 1s hydrogenic orbitals and M Coulomb or Yukawa potentials is given as an (M+N-1)-dimensional Feynman integral with external momenta and shifted coordinates. This is accomplished through the introduction of an integral transformation, in addition to the standard Feynman transformation for the denominators of the momentum representation of the terms in the product, which moves the resulting denominator into an exponential. This allows the angular dependence of the denominator to be combined with the angular dependence in the plane waves.

Decay Of Molecules At Corrugated Thin Metal Films, P.T. Leung, Young Sik Kim, Thomas F. George

Physics Faculty Publications and Presentations

The problem of the decay rate for molecules at corrugated thin metal films is considered theoretically via a classical phenomenological approach by generalization of a previous theory for a single rough surface. In particular, numerical results are worked out in detail for grating films with various possible arrangements of the two grating surfaces, and for both cases with a supported and a free-standing film. Effects due to cross coupling into the long- and short-range surface plasmons are observed, and correlations to recent experiments performed by Gruhlke, Holland, and Hall are made. It is suggested that fluorescence experiments with pulsed-laser excitations …

An Analysis Of The Inhibitory Effects Of Linolenic Acid Upon Photosystem Ii Of Higher Plants, Mark Edward Iven

Dissertations and Theses

This study utilizes steady state fluorescence measurements, flash-induced P680+ absorption transients, and DCIP reduction kinetics to study the inhibitory effects of linolenic acid (LA) upon Photosystem II (PSII) in whole spinach chloroplasts and insideout wheat thylakoids. It confirms the presence within PSII of LA-induced inhibition of energy trapping and/or primary charge separation (i.e., primary inhibition), in addition to donor side inhibition. The latter is diminished in the presence of 1,5-Diphenylcarbohydrazide (DPC) and probably takes place at the oxygen evolving complex. Primary inhibition, which is more controversial, probably occurs between Ph and QA, with a likely contribution at the level of …

Slope Stability As Related To Geology At Rainier, Columbia County, Oregon, James Douglas Gless

Dissertations and Theses

Rainier, Oregon, has experienced problems in the development of residential and commercial sites, utilities, and transportation facilities as a result of slope instability. This study of slope stability at Rainier was conducted at the request of city officials.

Sediment Dynamics On The Shore Slopes Of The Puget Island Reach Of The Columbia River, Oregon And Washington, Timothy Abbe

Dissertations and Theses

Water waves generated by wind and ships; ebb tidal currents; water level fluctuations; and dredging impact sediment transport in shallow water of the lower Columbia River. Observations were made over a one-year period after sand dredged from the navigation channel was placed at three study sites in the Puget Island region, 46°15'N 123°25'W, Oregon and Washington. Sediment composition is fine to medium grained, low density dacitic volcanics with small percentages of pumice, heavy minerals, and basalt.

The Chemistry Of Sulfonyl Fluorides: Sf5 And/Or So2f Containing Compounds As Precursors To Sulfonic Acids, Robin Joyce Terjeson

Dissertations and Theses

Sulfonyl fluoride systems and their derivatives, RS0₂F, where R represents hydrocarbon/fluorocarbon moieties continue to be of considerable interest. The incorporation of the sulfonyl fluoride group (S0₂F) into molecular systems can lead to compounds that are useful as ion-exchange resins, surface active agents, fuel cell electrolytes, and strong sulfonic acids/salts.

Interest in preparing SF₅ containing sulfonyl fluorides led to the synthesis of the ᵝ-sultone, SF₅CHCF₂0S0₂, and its rearranged product. Hydrolysis of the sultone gave SF₅CH₂S0₂F which led to the sulfonic acid and salt, SF …

Fluorinated [Beta]-Sultones As Precursors To Fluorinated Sulfonic Acids, And New Fluorosulfonyl Containing Monomers/Polymers, Javid Mohtasham

Dissertations and Theses

Sulfur trioxide (SO₃) adds to fluoroolefins of the form RCF=CF₂, (where R = F, SF₅, CF₃, CF₃OCF₂, CF₂=CF(CF₂)₂, CF₃(CF₂)₃O, CF₃O(CF₂)₂OCF₂, or CH₂ClCHClCH₂), yielding the fluorinated [beta]-sultones, RCFCF₂OSO₂. In the case of CF₃(CF₂)₃OCF=CF₂, a reverse addition occurs, giving the sultone, CF₃(CF₂)₃CF₂2OCFCF₂SO₂O. The fluoro [beta]-sultones are capable of undergoing different reactions, such as rearrangement, hydrolysis, esterification, and polymerization. These reactions, will result in the formation of compounds containing the fluorosulfonyl grouping (SO₂F); it is this group that yields the corresponding sulfonic acid upon base/acid treatment.

The addition of sodium bisulfite to CF₃CF= CF₂ and CF₃(CF₂)₄CF=CF₂ in the presence of (C₆H₅CO)₂O₂ and Na₂B₄O₇·10H₂O …

Chemical Modification Of Skeletal Muscle Sarcoplasmic Reticulum Vesicles: A Study Of Calcium Permeability, Janice F. Stuart

Dissertations and Theses

Skeletal muscle contains an internal membrane system called the sarcoplasmic reticulum (SR) whose function is to regulate the Ca²⁺ concentration of the myoplasm. Ca²⁺ is transported into the SR from the myoplasm via a Ca²⁺ dependent ATPase thus lowering the myoplasmic Ca²⁺ concentration. Ca²⁺ exits from the SR via a Ca²⁺ releqse pathway resultingin the increase of myoplasmic Ca²⁺. Muscles contract when the myoplasmic Ca²⁺ concentration is > 5 uM and relax when the Ca²⁺ concentration is lowered below 1 uM. The Ca²⁺ dependent ATPase has been extensively studied but …

Study Of Photolytic Interference On Ho Measurements By Lif-Fage, Carmen Ivette Martinez

Dissertations and Theses

For many years there has been a great interest among the scientific community in the study of the hydroxyl radical, HO. This interest stems from the fundamental role played by this molecule in the photochemistry of the atmosphere, mainly as a cleansing agent of environmental pollutants. Knowing the concentration of the radical would enable scientists to corroborate current atmospheric models and to predict future trends in the atmosphere. Even though there is a great interest in the determination of atmospheric concentrations of this molecule, the task has been very difficult. This is mainly due to the lack of a method …

Organizational Inducements And Social Motives: A Game Theoretic Analysis, Richard G. Davis

Dissertations and Theses

Game theory was used to analyze compensation systems based on individual and group incentives. Payoff formulas were developed for these incentives assuming different preferences for individual and social outcomes. Two levels of contributions were considered: (1) Defection. The minimum acceptable level of contributions, and (2) Cooperation. A level of discretionary contributions above the minimum. The discretionary contributions associated with cooperation were represented as a cost to the individual.

A classification scheme for uniform n-person games was developed using the approach of Rappaport and Guyer (1966) for 2 x 2 games. This classification scheme defines the natural outcome (cooperation or defection) …

Stratigraphy, Diagenesis, And Depositional Environment Of The Cowlitz Formation (Eocene), Northwest Oregon, Leonard Carl Farr Jr.

Dissertations and Theses

The Upper Eocene Cowlitz Formation is exposed in surface outcrops southwest of the town of Vernonia, in Columbia County, Oregon. The Cowlitz Formation also occurs in the subsurface of the Mist gas field where its Clark and Wilson (C and W) sandstone member (informal) acts as a natural gas reservoir, and its upper Cowlitz mudstone member (informal) acts as a cap rock. Surface exposures and continuous core were studied in order to determine Cowlitz Formation stratigraphy, and its depositional environment. Fresh core samples were also studied petrographically, and with a scanning electron microscope, in order to determine the effects of …

Analytically Reduced Form Of Multicenter Integrals From Gaussian Transforms, Jack C. Straton

Physics Faculty Publications and Presentations

In a previous paper the analytically reduced form was found for the general class of integrals containing multicenter products of ls hydrogenic orbitals, Coulomb or Yukawa potentials, and plane waves. The method consisted of combining all angular dependence within a single quadratic form by means of a three-dimensional Fourier transform and a one-dimensional Feynman transform for each term in the product and an additional integral transformation to move the resulting denominator into an exponential to be summed with the vector products in the plane waves. This quadratic form was then diagonalized with respect to the (introduced) momentum integrals and diagonalized …

Pressure Dependence Of Ozone Interference In The Laser Fluorescence Measurement Of Oh In The Atmosphere [Comment], Thomas M. Hard, C. Y. Chan, A. A. Mehrabzadeh, Robert J. O'Brien

Chemistry Faculty Publications and Presentations

The authors comment on the paper by Shirinzadeh et al. (Applied Optics, vol. 26, p. 2102, 1987). They point out three errors which caused the overprediction of spurious HO data.

A Study Of Oxygen Precipitation In Heavily Doped Silicon, Robert Kurt Graupner

Dissertations and Theses

Gettering of impurities with oxygen precipitates is widely used during the fabrication of semiconductors to improve the performance and yield of the devices. Since the effectiveness of the gettering process is largely dependent on the initial interstitial oxygen concentration, accurate measurements of this parameter are of considerable importance. Measurements of interstitial oxygen following thermal cycles are required for development of semiconductor fabrication processes and for research into the mechanisms of oxygen precipitate nucleation and growth. Efforts by industrial associations have led to the development of standard procedures for the measurement of interstitial oxygen in wafers. However practical oxygen measurements often …