Physical Sciences and Mathematics Commons^™

Geochemical Modeling Of Solubility And Speciation Of Uranium, Neptunium, And Plutonium, Zhongbo Yu, Yuyu Lin, Karen Johannesson, Amy J. Smiecinski, Klaus J. Stetzenbach

Publications (YM)

The purpose of this study is to model the solubility, speciation, and transport of three actinides: uranium (U), neptunium (Np), and plutonium (Pu) by a geochemical modeling tool under possible repository environmental conditions upon waste package failure. The dissolution concentration of three actinides in the waste package, their aqueous speciation after dissolving in the unsaturated zone (UZ), and transport processes in the saturated zone (SZ) along the groundwater flow path at Yucca Mountain (YM) are simulated by geochemical modeling calculations using PHREEQC. This model report was prepared in fulfillment of Groundwater Characterization at Yucca Mountain, Task II: Surface Complexation and …

The Paper Trail: Paper Use And Disposal At The University Of Rhode Island, Katherine Modzelewski

Senior Honors Projects

The University of Rhode Island has a well-established recycling program, however, the university community does not make full and proper use of the services and facilities provided. This project will specifically look at the use and disposal of paper products that are used for business and educational purposes at the University of Rhode Island and the effects these practices have both up- and down-stream. This analysis will be accomplished by examining the source and disposal of these university-used paper products through interviews with knowledgeable individuals, including those with oversight on the ordering, management, and disposal of professional paper products, a …

Mechanics Of Suction Generation During Feeding In Little Skates, Danielle Duquette

Senior Honors Projects

Feeding mechanisms of aquatic vertebrates has been extensively studied in the past, while that of elasmobranchs remains limited. Skates and rays are believed to have evolved from a shark ancestor, thus they represent the most derived group. All skates are dorsoventrally compressed, have a unique jaw suspension type and head skeleton and live in benthic environments. It is unknown whether these derived features of skates have altered the ancestral shark feeding mechanism. Comparing feeding mechanisms in skates and sharks may shed light on morphological transformations that have arisen after the evolutionary split of these two groups. In this study prey …

Synthesis Of Polythiophenes Using Oxidative Coupling, Suchismita Datta

Senior Honors Projects

Polythiophenes are polymerization products (also known as polymers) of thiophenes (which are sulfur heterocycles). Polythiophenes become conducting as a result of electron interactions in the conjugated pi-orbitals (of the double bonds) via doping (intentionally adding elemental impurities).This semiconductor-type property of Polythiophenes makes them of special interest to material-science-type applications. They have been dubbed as “synthetic metals”. (www.wikipedia.com) The optical properties of Polythiophenes respond to environment stimuli such as changes in solvent, temperature and applied potential with prominent color shifts. These changes make Polythiophenes attractive sensors. They are also used in the LED display and semiconductor fields. The aim of this …

Watching Ultrafast Barrierless Excited-State Isomerization Of Pseudocyanine In Real Time, Benjamin Dietzek, Arkady Yartsev, Alexander N. Tarnovsky

Chemistry Faculty Publications

The photoinduced excited-state processes in 1,1'-diethyl-2,2'-cyanine iodine are investigated using femtosecond time-resolved pump-probe spectroscopy. Using a broad range of probe wavelengths, the relaxation of the initially prepared excited-state wavepacket can be followed down to the sink region. The data directly visualize the directed downhill motion along the torsional reaction coordinate and suggest a barrierless excited-state isomerization in the short chain cyanine dye. Additionally, ultrafast ground-state hole and excited-state hole replica broadening is observed. While the narrow excited-state wavepacket broadens during pump-probe overlap, the ground-state hole burning dynamics takes place on a significantly longer time-scale. The experiment reported can be considered …

Σary, Minnesota State University Moorhead, Mathematics Department

Math Department Newsletters

No abstract provided.

The Sensitivity Of The Southwest Monsoon Phytoplankton Bloom To Variations In Aeolian Iron Deposition Over The Arabian Sea, Jerry D. Wiggert, Raghu G. Murtugudde

CCPO Publications

[1] A coupled, 3-D biophysical ocean general circulation model is used to investigate how aeolian iron deposition affects the Arabian Sea ecosystem. Two separate aeolian iron deposition fields, derived from the GISS and GOCART atmospheric transport models, have been applied as surface boundary conditions. The model results exhibit widespread biogeochemical sensitivity to the choice of deposition field. With GOCART deposition, SW Monsoon phytoplankton blooms in the western and central Arabian Sea are enhanced and exhibit greater realism. The central Arabian Sea bloom is supported by supplemental input of horizontally advected iron from a pool that undergoes a yearlong progression that …

Local Effective Potential Theory: Nonuniqueness Of Potential And Wave Function, Viraht Sahni, Marlina Slamet, Xiao-Yin Pan

Physics Faculty Publications

In local effective potential energy theories such as the Hohenberg-Kohn-Sham density functional theory (HKS-DFT) and quantal density functional theory (Q-DFT) electronic systems in their ground or excited states are mapped to model systems of noninteracting fermions with equivalent density. From these models, the equivalent total energy and ionization potential are also obtained. This paper concerns the nonuniqueness of the local effective potential energy function of the model system in the mapping from a nondegenerate ground state, the nonuniqueness of the local effective potential energy function in the mapping from a nondegenerate excited state, and in the mapping to a model …

Electronic Anisotropy Between Open Shell Atoms In First And Second Order Perturbation Theory, Gerrit C. Groenenboom, Xi Chu, R. Krems

Chemistry and Biochemistry Faculty Publications

The interaction between two atoms in states with nonzero electronic orbital angular momenta is anisotropic and can be represented by a spherical tensor expansion. The authors derive expressions for the first order (electrostatic) and second order (dispersion and induction) anisotropic interaction coefficients in terms of the multipole moments and dynamic polarizabilities of the atoms and show that a complete description of the second order interaction requires odd rank or "out-of-phase" polarizabilities. The authors relate the tensorial expansion coefficients to the adiabatic Born-Oppenheimer potentials of the molecule and show that there are linear, and in some cases nonlinear, constraints on the …

Sas Macro For Hierarchical Dependence In Meta Analysis, Matthew Wayne Maw

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

This project implemented a simple and useful SAS (Statistical Analysis Software) macro for meta-analysis. The macro was specifically designed for hierarchically dependent meta-analysis but may also be used for independent meta-analysis. Two data files are necessary for this macro. One data file contains the study names, control and treatment group sizes with corresponding means and standard errors, covariates to be tested, an indicator variable noting hierarchically dependent study groups, and a variable providing the degrees of freedom for interdependent studies. The second file contains a variance/covariance matrix for the studies. The macro returns useful information such as study estimates and …

Black-Scholes And Extended Black-Scholes Models: A Comparative Statistical Analysis, Bradley Thomas Bush

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Much research has been done on options pricing. Black and Scholes [12] set the benchmark in 1973 with their model for arbitrage-free, risk-neutral options valuation. Arbitrage-free refers to a market environment where prices are such that trading opportunities with no risk do not exist and risk-neutral commodities earn a risk free interest rate. Since then the literature has seen a multitude of models improving the fit of the traditional Black -Scholes (BS) model. A brief overview of options and these models is given. A derivation and discussion of BS is followed by a derivation and discussion of the Extended Black-Scholes …

Decomposing Vector Space Representations Of The Lie Algebras S[2c And S[2r, Brian W. Gleason

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

It is known that any finite-dimensional representation of a semi-simple Lie algebra is decomposable into a direct sum of irreducible representations. Here we prove some theoretical results that allow us to construct an efficient algorithm for computing such a decomposition for representations of s[2C and s[2R. We then implement this algorithm in a procedure for the computer algebra system Maple that will quickly and easily perform the decomposition. We also give several examples of this decomposition performed by the procedure in order to illustrate its advantages over calculations done ‘by hand'.

Lidar As A Shoreline Mapping Tool, Shachak Pe'eri, C. W. Morgan, William D. Philpot, G Guenther, Andy Armstrong

Center for Coastal and Ocean Mapping

No abstract provided.

High Resolution Mapping In Support Of Unclos Article 76: Seeing The Seafloor With New Eyes, James V. Gardner, Larry A. Mayer, Andy Armstrong

Center for Coastal and Ocean Mapping

Since 2003, the Center for Coastal & Ocean Mapping/Joint Hydrographic Center at the University of New Hampshire (UNH) has been conducting multibeam mapping of many U.S. continental margins in areas where there is a potential for an extended continental shelf as defined under Article 76 of the United Nations Convention on the Law of the Sea. UNH was directed by Congress, through funding by the National Oceanic & Atmospheric Administration, to map the bathymetry in areas in the Arctic Ocean, Bering Sea, Gulf of Alaska, Northwest Atlantic, northern Gulf of Mexico, the Northern Mariana Islands, Kingman Reef and Palmyra Atoll …

Multi-Channel Digital Fringe Calibration For Structured Light Profilometers Using Neural Networks, Matthew J. Baker, Jiangtao Xi, Joe F. Chicharo

Faculty of Informatics - Papers (Archive)

The performance of structured light profilometers is significantly hindered by the generation of distorted sinusoid fringe images, particularly, for multi-channel applications. In this paper we investigate the application of neural network fringe calibration for the multi-channel approach. We analytically review the nature of the major error sources associated with the multi-channel approach and propose afringe calibration technique with emphasis on minimal photometric calibration. The performance of the calibration technique is gauged through both simulation and experimentation.

Structural Properties Of Formal Polynomial Algebras In Noncommuting Or Nonassociating Indeterminates, Serge C. Ballif

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In order to enlarge the class of equations provided by traditional polynomials over a binary algebra A to a more useful class of equations, we introduce polynomials in noncommuting or nonassociating indeterminates. We discuss algebraic properties of these formal polynomial algebras and their accompanying polynomial function algebras. We present certain basis results for polynomial algebras, which are used to address the question of zero divisors in a polynomial algebra. We give an analog of the remainder theorem and the factor theorem for polynomials. Particular emphasis is placed on showing the difference between polynomials and polynomial functions. We also provide a …

Qcd Equation Of State With 2+1 Flavors Of Improved Staggered Quarks, James E. Hetrick, C. Bernard

All Faculty Articles - School of Engineering and Computer Science

We report results for the interaction measure, pressure, and energy density for nonzero-temperature QCD with 2+1 flavors of improved staggered quarks. In our simulations, we use a Symanzik improved gauge action and the Asqtad O (a2) improved staggered quark action for lattices with temporal extent Nt = 4 and 6. The heavy quark mass ms is fixed at approximately the physical strange quark mass and the two degenerate light quarks have masses mud ≈ 0.1ms or 0.2ms. The calculation of the thermodynamic observables employs the integral method where energy density and pressure are obtained by integration over the interaction measure.

Hydrothermal Crystal Growth Of Oxides For Optical Applications, Colin Mcmillen

All Dissertations

There is great interest in obtaining coherent radiation in all regions of the optical spectrum. This dissertation explores the hydrothermal growth of crystals that function in two regions currently inaccessible by solid state devices. The first gap exists in the deep-UV region, particularly below 200 nm. Some materials such as LBO and BBO can generate coherent light at wavelengths as low as 205 nm. The growth of these materials was explored to investigate the feasibility of the hydrothermal method as a new technique for growing these crystals. Particular attention was paid to the descriptive chemistry surrounding these systems, and several …

The Glow Discharge - A Multifaceted Optical Emission Source: From Solids Analysis To Metalloproteins, Timothy Brewer

All Dissertations

Glow discharges (GD) are well known for their application to direct solids elemental analysis of metals and alloys by optical emission spectroscopy (GD-OES). The most successful application of GD-OES has been the analysis of solid materials since the GD provides rapid, direct bulk and depth profiling analysis of solids, metals, powders, polymers, glasses and ceramics. However, solids analysis has typically suffered from the lack of true analytical blanks and the inability to study particulate solids in their native state. An approach for the analysis of solid powdered material entrapped in a sol-gel matrix by radio frequency glow discharge optical emission …

Algorithms And Complexity For Alliances And Weighted Alliances Of Various Types, Lindsay Jamieson

All Dissertations

The concept of alliances was introduced in 2002 in a paper by Kristiansen, Hedetniemi and Hedetniemi. Although research has been published on the mathematical properties of various types of alliances, until recently, no research has been done to develop algorithms or establish the complexity of decision problems for alliances in graphs.
This thesis presents the first algorithmic study of alliances in graphs. We present linear algorithms for finding various alliance numbers in trees and series parallel graphs. These linear algorithms are designed using a new methodology based on the well-established Wimer methodology for designing polynomial algorithms on k-terminal graphs. Linear …

Functionalized Nanomaterials: Synthesis, Characterization, And Applications, Liangwei Qu

All Dissertations

Due to their unique electronic, optical, catalytic and mechanical properties, nanomaterials (nanoparticles and nanotubes) have been attracting much attention over the past decades. In this dissertation, polymeric nanoparticles bearing derivatized D-mannose and galactose molecules were prepared via dispersion polymerization and their interactions with various bacterial cells were studied. The results show that there are strong adhesin-specific interactions of the nanoparticles with E. coli cells, resulting significant nanoparticles-madiated cell agglutination.
Poly(ethylene glycol)-coated magnetic polymer nanoparticles were synthesized through miniemulsion polymerization by using macromonomer as both a comonomer and a surfactant. The resulting magnetic polymer nanoparticles were successfully used for bio-detection and …

Raman Spectroscopic Evidence For Anharmonic Phonon Lifetimes And Blueshifts In 1d Structures, Rahul Rao

All Dissertations

Anharmonic effects in two different quasi-1D systems were probed via micro-Raman spectroscopy. In the first system, we observed upshifts of peaks in the Raman spectra for b-Ga2O3 nanowires grown along the [110] growth direction compared those present in bulk b-Ga2O3. Contrary to our Raman studies on -Ga2O3 nanowires, downshifts in the Raman spectrum for b-Ga2O3 nanowires grown along [401] direction has also been reported by other research groups. We attribute these Raman shifts to the growth direction-induced lattice strains (compressive and tensile) present in the nanowires, and present a model based on the quasi-harmonic density functional theory to support our …

Late Cambrian (Steptoean) Sedimentation And Responses To Sea-Level Change Along The Northeastern Laurentian Margin: Insights From Carbon Isotope Stratigraphy, Bosiljka Glumac, Laurel E. Mutti

Geosciences: Faculty Publications

Carbon isotopes are applied as tools for stratigraphic correlation of poorly fossiliferous Upper Cambrian carbonate strata in the northern U.S. Appalachians. Upper Cambrian (Steptoean) marine carbonate rocks record a significant global positive carbon isotope excursion (δ 13C = +4‰-5‰ Vienna Peedee belemnite [VPDB]), the timing of which is well documented in fossiliferous sections elsewhere. The Steptoean excursion peaks at a sea-level lowstand that produced the Sauk II-Sauk III sequence boundary on the North American craton. In this study, this excursion is documented for the first time in the northern U.S. Appalachians in poorly exposed limestone debris flow and olistolith deposits …

A Method For Finding Standard Error Estimates For Rma Expression Levels Using Bootstrap, Gabriel Nicholas

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Oligonucleotide arrays are used in many applications. Affymetrix GeneChip arrays are widely used. Before researchers can use the information from these arrays, the raw data must be transformed and summarized into a more meaningful and usable form. One of the more popular methods for doing so is RMA (Robust Multi-array Analysis).

A problem with RMA is that the end result (estimated gene expression levels) is based on a fairly complicated process that is unusual. Specifically, there is no closed-form estimate of standard errors for the estimated gene expression levels. The current recommendation is to use a naive estimate for the …

Bimodality Revisited, Thomas R. Knapp

Journal of Modern Applied Statistical Methods

Degree of bimodality is an important feature of a frequency distribution, because it could suggest heterogeneity, such as polarization or two underlying distributions combined into one. The literature contains several measures of bimodality. This article attempts to summarize most of those measures, with their attendant advantages and disadvantages.

Ordinal Versions Of Coefficients Alpha And Theta For Likert Rating Scales, Bruno D. Zumbo, Anne M. Gadermann, Cornelia Zeisser

Journal of Modern Applied Statistical Methods

Two new reliability indices, ordinal coefficient alpha and ordinal coefficient theta, are introduced. A simulation study was conducted in order to compare the new ordinal reliability estimates to each other and to coefficient alpha with Likert data. Results indicate that ordinal coefficients alpha and theta are consistently suitable estimates of the theoretical reliability, regardless of the magnitude of the theoretical reliability, the number of scale points, and the skewness of the scale point distributions. In contrast, coefficient alpha is in general a negatively biased estimate of reliability. The use of ordinal coefficients alpha and theta as alternatives to coefficient alpha …

Tests For Treatment Group Equality When Data Are Nonnormal And Heteroscedastic, Robert A. Cribbie, Rand R. Wilcox, Carmen Bewell, H. J. Keselman

Journal of Modern Applied Statistical Methods

Several tests for group mean equality have been suggested for analyzing nonnormal and heteroscedastic data. A Monte Carlo study compared the Welch tests on ranked data and heterogeneous, nonparametric statistics with previously recommended procedures. Type I error rates for the Welch tests on ranks and the heterogeneous, nonparametric statistics were well controlled with a slight power advantage for the Welch tests on ranks.

On The Properties Of Beta-Gamma Distribution, Lingji Kong, Carl Lee, J.H. Sepanski

Journal of Modern Applied Statistical Methods

A class of generalized gamma distribution called the beta-gamma distribution is proposed. Some of its properties are examined. Its shape can be reversed J-shaped, unimodal, or bimodal. Reliability and hazard functions are also derived, and applications are discussed.

Lq-Moments For Statistical Analysis Of Extreme Events, Ani Shabri, Abdul Aziz Jemain

Journal of Modern Applied Statistical Methods

Statistical analysis of extremes is conducted for predicting large return periods events. LQ-moments that are based on linear combinations are reviewed for characterizing the upper quantiles of distributions and larger events in data. The LQ-moments method is presented based on a new quick estimator using five points quantiles and the weighted kernel estimator to estimate the parameters of the generalized extreme value (GEV) distribution. Monte Carlo methods illustrate the performance of LQ-moments in fitting the GEV distribution to both GEV and non-GEV samples. The proposed estimators of the GEV distribution were compared with conventional L-moments and LQ-moments based on linear …

Modeling Longitudinal Ordinal Response Variables For Educational Data, Ann A. O'Connell, Heather Levitt Doucette

Journal of Modern Applied Statistical Methods

This article presents applications for the analysis of multilevel ordinal response data through the proportional odds model. Data are drawn from the public-use Early Childhood Longitudinal Study. Results showed that gender, number of family risk characteristics, and age at kindergarten entry were associated with initial reading proficiency (0 to 5 scale). The number of family risks and age were associated with time-slopes. Three issues are highlighted: building multilevel ordinal models, interpretation of multilevel effects; and determination of predicted probabilities based on results of the multilevel proportional odds models.