Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 30 of 31

Full-Text Articles in Physical Sciences and Mathematics

A Comparative Study Of Photomultiplier Tubes And Charge Coupled Devices In Glow Discharge-Optical Emission Spectrometry, Robert James Broadwater Dec 2003

A Comparative Study Of Photomultiplier Tubes And Charge Coupled Devices In Glow Discharge-Optical Emission Spectrometry, Robert James Broadwater

Masters Theses

This Masters Thesis compared two glow discharge-optical emission spectrometers designed around two different types of detectors: the photomultiplier tube (PMT) and the charge-coupled device (CCD). The two instruments compared were the LECO SA2000 (PMT-based) and the LECO GDS500a (CCD-based). Detection limit, dynamic range, precision, accuracy, and drift were determined to compare the detection systems between 165 and 450nm.

The PMT-based system outperformed the CCD-based system in all five of the categories studied based on the initial protocol. However, it was shown that improvements could be made in four of the five categories studied by exploiting the CCDs ability to monitor …


Laboratory Testing Of Select Geotextiles As Biointrusion Barriers And Sediment Filters, David R. Beck Dec 2003

Laboratory Testing Of Select Geotextiles As Biointrusion Barriers And Sediment Filters, David R. Beck

Masters Theses

It has been proposed that placing a geotextile over sediments with adsorbed contaminants can prevent bioaccumulation of the contaminants in larger animals by isolating the benthic organisms living within these sediments from fish. In conjunction with a field study carried out at Gull Creek, a laboratory study testing two geotextiles as biointrusion barriers and sediment filters was conducted.

Constant-head permeameters were run for seven days using cores from the field study area with a geotextile placed over the cores. For biointrusion barrier tests, medium sand was placed over the geotextile and spiked with nutrients. Following each trial, benthic organisms in …


Isosurface Extraction In The Visualization Toolkit Using The Extrema Skeleton Algorithm, Subha Parvathy Mahaadevan Dec 2003

Isosurface Extraction In The Visualization Toolkit Using The Extrema Skeleton Algorithm, Subha Parvathy Mahaadevan

Masters Theses

Generating isosurfaces is a very useful technique in data visualization for understanding the distribution of scalar data. Often, when the size of the data set is really large, as in the case with data produced by medical imaging applications, engineering simulations or geographic information systems applications, the use of traditional methods like marching cubes makes repeated generation of isosurfaces a very time consuming task. This thesis investigated the use of the Extrema Skeleton algorithm to speed up repeated isosurface generation in the visualization package, Visualization Toolkit (VTK). The objective was to reduce the number of non-isosurface cells visited to generate …


Geophysical Characterization Of A Former Refinery Site, Kalamazoo, Michigan, Baraka Damas Kinabo Dec 2003

Geophysical Characterization Of A Former Refinery Site, Kalamazoo, Michigan, Baraka Damas Kinabo

Masters Theses

Lakeside, a former refinery site, in Kalamazoo, Michigan, is contaminated with hydrocarbon products. The contamination resulted from the refining and storage activities that took place at the site for over 50 years. The contamination is scattered in isolated pockets.

In an attempt to better define the contamination zones and therefore assist the remediation efforts, this study uses shallow geophysical methods including Electromagnetic induction using the EM 31 system, Magnetic, Ground Penetrating Radar (GPR), and Resistivity methods. The hand auger was used to further characterize some EM 31 anomalies. The EM 31 conductivity results show elevated values resulting from the biodegradation …


Capillary Electrophoretic Separations Of Metal Ions, Elena Hofman Dec 2003

Capillary Electrophoretic Separations Of Metal Ions, Elena Hofman

Masters Theses

Transition-metal (Zn(II), Co(II), Ni(II) and Cu(II)) ion separation was studied using 8-hydroxyquinoline-5-sulfonic acid and 2-methyl-8-hydroxyquinoline ligands with surfactants (cationic and anionic) by capillary electrophoresis under a variety of conditions (like pH, ionic strength, voltage and ion, ligand and surfactant amounts) and has debuted a clear separation mechanism. With cationic surfactants, ligands compete with capillary surface silanols for the metal ions; with anionic surfactants, ligands, silanols and micelles compete.

An empirical parameter, Ke, (electrophoretic-mobilities based) rationalizing the separation was proposed, experimentally analyzed and supported; it provides a silanol group per cm2 value of the capillary surface, an equilibrium …


Monte Carlo Simulations And Analysis Of Single-Molecule Detection And Imaging, Peter Williams Dec 2003

Monte Carlo Simulations And Analysis Of Single-Molecule Detection And Imaging, Peter Williams

Masters Theses

Computer modeling and analysis methods are developed for two modes of operation of an instrument for sensitive fluorescence detection of individual dye-labeled molecules in solution. First, Monte Carlo simulations of experiments for single-molecule imaging (SMI) are extended to include effects of sample flow, sticking of molecules to surfaces, and the finite depth-of-focus of the optics. The results have a bearing on a patented method for high-speed single-molecule DNA sequencing. They indicate that the imaging of freely moving fluorescent labels within a microfluidic flowcell will be considerably more involved than that of immobilized molecules at a surface, which is the usual …


3d Visualization Modules For Chemical Engineering – A Web-Based Approach Using Java And Opengl, Sharad Anant Gupta Dec 2003

3d Visualization Modules For Chemical Engineering – A Web-Based Approach Using Java And Opengl, Sharad Anant Gupta

Masters Theses

The main objective of this work is to implement web-based educational modules for chemical engineering students. Phase behavior is a topic with which the students seem to struggle with, particularly for mixtures, where a 2-D representation of the phase diagram falls far short of the understanding a 3-D model can provide. Using the platform-independence of Java and the graphics capability of OpenGL, three phase diagram Java applets have been developed. Users can view these web-based 3D applets by installing a plug-in. These modules provide users with an ability to rotate the 3D models, slice through them, zoom into them and …


A Class Of Functions That Are Quasiconvex But Not Polyconvex, Catherine S. Remus Dec 2003

A Class Of Functions That Are Quasiconvex But Not Polyconvex, Catherine S. Remus

Masters Theses

In 1991 V. Sverak [11] gave an example of a function that was invariant and quasiconvex but not polyconvex. We have generalized this example to a wide class of functions that meet certain ellipticity and growth conditions. Quasiconvexity is one necessary and sufficient condition for the existence of solutions to the minimization problem in elliptic P.D.E. theory. Invariance is frequently a requirement of the stored energy function in Calculus of Variation approaches to elasticity problems.


Itera- Tive Reconstruction Framework For High-Resolution X-Ray Ct Data, Thomas Matthew Benson Dec 2003

Itera- Tive Reconstruction Framework For High-Resolution X-Ray Ct Data, Thomas Matthew Benson

Masters Theses

Small animal medical imaging has become an important tool for researchers as it allows noninvasively screening animal models for pathologies as well as monitoring dis- ease progression and therapy response. Currently, clinical CT scanners typically use a Filtered Backprojection (FBP) based method for image reconstruction. This algorithm is fast and generally produces acceptable results, but has several drawbacks. Firstly, it is based upon line integrals, which do not accurately describe the process of X-ray attenuation. Secondly, noise in the projection data is not properly modeled with FBP. On the other hand, iterative algorithms allow the integration of more complicated sys- …


Electrical Conductivity Measurements Of Lithium-Ammonia Solutions, Mariana Constantin Barbu Aug 2003

Electrical Conductivity Measurements Of Lithium-Ammonia Solutions, Mariana Constantin Barbu

Masters Theses

The topic covered in this thesis is the study of electronic interactions for liquid metal-ammonia solutions, lithium-ammonia solutions in particular. To obtain a theoretical understanding of so-called correlated electron systems.

The work focuses on sample creation and measurement of electrical conductivity of lithium-ammonia solutions varying with temperature for different concentrations. We have taken measurements in liquid lithium-ammonia mixtures using four-wire method to minimize the contact resistance. We have shown how it is possible to carry out accurate measurements of the electrical conductivity in these systems with the four wire measurements.


Application Of Geochemical Fingerprinting And Isotopes To Identity Landfill Gas Impacts To Groundwater, Eric E. Wallis Aug 2003

Application Of Geochemical Fingerprinting And Isotopes To Identity Landfill Gas Impacts To Groundwater, Eric E. Wallis

Masters Theses

Volatile organic compounds (VOCs) are detected in two groundwater monitoring wells (MW-60 and MW-62S) located along the northern, downgradient property line of the McGill Road Landfill (MRL) in Jackson, Michigan. Potential on-site sources for groundwater impact are two distinct landfill units at the MRL. Leachate chemistry suggested that landfill leachate was not the source of VOCs detected in groundwater. A potential source for VOCs was landfill gas. Sources of landfill gas in the vicinity of the impacted wells included the distinct MRL landfill units as well as the old Jackson County Landfill (JCL), located hydraulically downgradient from the impacted wells. …


Integrated Visualization Of Diffusion Tensor And Functional Mri, Nathaniel Richard Fout Aug 2003

Integrated Visualization Of Diffusion Tensor And Functional Mri, Nathaniel Richard Fout

Masters Theses

To understand the morphology, structure, and function of the human brain and the underlying relationships therein has long been a goal of mankind. Technologies are constantly emerging and evolving in an effort to realize this goal, with each new development potentially providing another piece of the puzzle. Among those technologies are advanced imaging modalities such as Diffusion Tensor MRI (DT-MRI) [2] and Functional MRI (fMRI) [8], whose purpose is to provide deeper insight into the neural network connecting functional units of the cerebral cortex. More specifically, DT-MRI captures a description of the fibrous structures (such as nerve fibers) in the …


Fractal Images Generated By Newton's Method.", Jennifer Corte Aug 2003

Fractal Images Generated By Newton's Method.", Jennifer Corte

Masters Theses

We investigate the behavior of Newton's Method for finding roots applied to complex-valued functions of complex variables. This re- quires an analysis of iteration of rational functions. The fractal nature of Newton's Method in the complex plane gives us intricate and beautiful images. By investigating select functions we attempt to generalize a pattern of behavior.


Structural And Stratigraphic Investigations At The Southwest End Of The Tellico-Sevier Syncline, Southeast Tennessee, Milan A. Heath Ii Aug 2003

Structural And Stratigraphic Investigations At The Southwest End Of The Tellico-Sevier Syncline, Southeast Tennessee, Milan A. Heath Ii

Masters Theses

The southern Appalachian Valley and Ridge is composed of a wedge of Cambrian through Pennsylvanian siliciclastic and carbonate rocks, deformed during latest Paleozoic by the collision of Laurentia and Gondwana. This collision caused the southern Appalachian foreland fold-thrust belt to deform as a critically tapered wedge. This study utilized structural and stratigraphic data to examine the mechanical behavior and timing of emplacement of the southwest end of the Tellico-Sevier syncline within this wedge. The study area is located in southeast Tennessee at the southwest end of the Tellico-Sevier syncline, which is in the first Valley and Ridge thrust sheet west …


Trochoidal Electron Impact Time-Of-Flight Mass Spectrometry Of Chlorodifluoromethane, Wesley Daniel Robertson Aug 2003

Trochoidal Electron Impact Time-Of-Flight Mass Spectrometry Of Chlorodifluoromethane, Wesley Daniel Robertson

Masters Theses

A Time-of-Fight mass spectrometer (TOF-MS) equipped with both a standard electron gun and a trochoidal electron monochromator was constructed and made operational and used to study ionization processes of the molecule Chlorodifluoromethane (CHF2Cl). The appearance energies of both the parent ion (CHF2Cl+) and the most intense fragment ion (CHF2+) were carefully analyzed and it was observed that the energy for formation of the parent ion, (CHF2Cl+) at 12.50 eV, was at a higher energy than the fragment ion, (CHF2+) at 12.25 eV. This phenomenon …


Optical Solitons In A Three-State Medium, Talal Ghannam Jun 2003

Optical Solitons In A Three-State Medium, Talal Ghannam

Masters Theses

When a beam of light propagates within a typical medium, absorption is a common phenomenon. This happens when the frequency of the light is close to a resonant frequency of the atoms composing the medium. But in the past few decades, it has been shown that in certain circumstances, carefully chosen pulse shapes are able to propagate without significant absorption even when the frequency of the light is close to an atomic resonant frequency. It was called Self Induced Transparency (SIT).

This phenomenon was intensively studied in the two-state systems. On the other hand, the three-state systems seems not to …


Stratigraphy Of Lake Michigan Lobe Deposits In Van Buren County, Michigan, Steven P. Beukema Jun 2003

Stratigraphy Of Lake Michigan Lobe Deposits In Van Buren County, Michigan, Steven P. Beukema

Masters Theses

The surficial glacial deposits and landforms of Van Buren County were recently mapped at a 1:24,000 scale as part of a STATEMAP project. Several borings were drilled to supplement the surface data. Six of these borings were characterized in detail by means of gamma ray logging, textural analysis, and X-ray diffraction of the clay-sized fraction of the diamicton units.

Results from this study reveal two diamicton units at stratigraphically distinct positions that can be correlated across the county and that are separated by a thick sequence of lacustrine sediments. Correlation of diamicton and lacustrine units was accomplished by analyzing several …


A Coarse-Grain Parallel Implementation Of The Block Tridiagonal Divide And Conquer Algorithm For Symmetric Eigenproblems., Robert M. Day May 2003

A Coarse-Grain Parallel Implementation Of The Block Tridiagonal Divide And Conquer Algorithm For Symmetric Eigenproblems., Robert M. Day

Masters Theses

Cuppen’s divide and conquer technique for symmetric tridiagonal eigenproblems, along with Gu and Eisenstat’s modification for improvement of the eigenvector computation, has yielded a stable, efficient, and widely-used algorithm. This algorithm has now been extended to a larger class of matrices, namely symmetric block tridiagonal eigenproblems. The Block Tridiagonal Divide and Conquer algorithm has shown several characteristics that make it suitable for a number of applications, such as the Self-Consistent-Field procedure in quantum chemistry.

This thesis discusses the steps taken to implement a coarse-grain parallel version of the Block Tridiagonal Divide and Conquer algorithm, suitable for a parallel supercomputer or …


Thermal Evolution Of Planetesimals And Protoplanets In The Terrestrial Planet Region: Code Optimization And Implementation On A Distributed Grid Using Netsolve, Amitabha Ghosh May 2003

Thermal Evolution Of Planetesimals And Protoplanets In The Terrestrial Planet Region: Code Optimization And Implementation On A Distributed Grid Using Netsolve, Amitabha Ghosh

Masters Theses

A code for asteroidal heat transfer and growth is optimized for performance. The Gauss elimination routine for the solver is replaced by a sparse matrix routine. Finite element matrix assembly operations are rewritten to reduce operations involving 3D arrays to 1D. Advantage is taken of the sparse matrix structure of finite element matrices in reducing 2D arrays to 1D. The number of vector touches are reduced to the extent possible, by carrying over statements from one iteration to the next. The number of do loops are reduced by merging several do loops into one. The optimization reduced the CPU time …


Geology Of Part Of The Southwestern Brushy Mountains, Inner Piedmont, North Carolina, And The Geochemistry Of Western Inner Piedmont Migmatite, James L. Kalbas May 2003

Geology Of Part Of The Southwestern Brushy Mountains, Inner Piedmont, North Carolina, And The Geochemistry Of Western Inner Piedmont Migmatite, James L. Kalbas

Masters Theses

The newly defined boundary between the western and eastern Inner Piedmont belts has been the focus of several recent tectonic studies in the southern Appalachians. Specifically, the Brindle Creek fault was recognized in southwestern North Carolina as a thrust that juxtaposed Siluro-Devonian-age paragneisses (now-known) and Devonian and Mississippian granites atop Neoproterozoic- to Cambrian-age paragneisses, Middle Ordovician volcanic and metasedimentary rocks, and Ordovician intrusive units.

Detailed geologic mapping in the Kings Creek 7.5-minute quadrangle, southwestern Brushy Mountains, Caldwell County, North Carolina, revealed the northeastern continuation of the thrust. Recognition of the northeastern extension of the fault, and analysis of small -scale …


Sparta: A Graphical User Interface For Malicious Mobile Code Fingerprint-Ing., Victor P. De Cerqueira May 2003

Sparta: A Graphical User Interface For Malicious Mobile Code Fingerprint-Ing., Victor P. De Cerqueira

Masters Theses

This thesis introduces and describes SPARTA (for Stochastic Profiling Application for the Rendering of Trees and Automata), a graphical user interface used as a front end to a collection of tools written in C that collectively convert a log of registry system calls performed by an application into binary descriptions of PSTs (for Probabilistic Suffix Trees) and PSAs (for Probabilistic Suffix Automata), which are models used to represent application behavior on Windows-based systems. SPARTA works by rendering these binary descriptions into graphical form, showcasing a variety of features intended to make the user interaction with PSTs and PSAs informative and …


A Geochemical Survey Of The Natural Waters Of Belize, Central America, Anthony D. Marfia Apr 2003

A Geochemical Survey Of The Natural Waters Of Belize, Central America, Anthony D. Marfia

Masters Theses

A geochemical survey of the natural waters in Belize, Central America was carried out to compliment routine water quality analysis and to identify processes affecting water quality. The objective of this research was to provide a geochemical assessment of natural waters throughout Belize by examining select major ions (Ca2+, Mg2+ , SO42-), and stable isotopes of carbon (13C), oxygen (18O) and hydrogen (2H).

The dominant geology relevant to this investigation comprises a varied landscape of carbonates and elastic sediments in a subtropical rainforest/savannah climate. Stable oxygen and hydrogen …


Development Of Kohonen Neural Network Application As A Pattern Recognition System For An Electronic Nose, Lori Lynn Evesque Apr 2003

Development Of Kohonen Neural Network Application As A Pattern Recognition System For An Electronic Nose, Lori Lynn Evesque

Masters Theses

Electronic noses are used to identify and characterize unknown odors in industry. Chemometrics and neural network algorithms are used as pattern recognition systems for these devices. Experimentation with Kohonen clustering as the pattern recognition system for electronic noses was not noted prior to 1997. [BEG] This thesis investigated the use of a Kohonen neural network algorithm as a clustering algorithm for electronic nose data using the chemometrics algorithms built into the electronic nose as a performance standard. A secondary aim was to improve the clustering and identification capabilities of the Kohonen network.

The unsupervised Kohonen network was not able to …


Chlorobenzenes And Chloronitrobenzenes Interaction With Iron (O), Manuel Alejandro Serratos Jan 2003

Chlorobenzenes And Chloronitrobenzenes Interaction With Iron (O), Manuel Alejandro Serratos

Masters Theses

Degradation of chlorobenzene, dichlorobenzenes and chloronitrobenzenes (ClB, x-Cl2B and x-ClNO2B) was tested by trying to make them react with metallic iron, Fe (0), in water solvent.

The experiments consisted of optimizing the parameters of the reactions (like minimum mass of iron needed) and analytical detection conditions. Analytical techniques used were gas and liquid chromatography (GC and HPLC), mass spectrometry (MS) and UV-Vis spectroscopy.

No substances other than the initial ClB and x-Cl2B were detected in their tests with Fe (0) after shaking for periods of up to three days, although 10%weight average decreases in concentration were observed.

The ClNO2B isomers …


Dmap As A Catalyst For Carbon Acylation: Elucidation Of Mechanistic Pathway, Including Spectral Characterization Of The Putative Reactive Intermediate, Jagadish K. Boppisetti Jan 2003

Dmap As A Catalyst For Carbon Acylation: Elucidation Of Mechanistic Pathway, Including Spectral Characterization Of The Putative Reactive Intermediate, Jagadish K. Boppisetti

Masters Theses

3-Phenylbenzofuranone, when deprotonated with sodium hydride, forms an extended enolate system which, when treated with excess alkyl chloroformates, affords only oxygen-acylated products, as opposed to the usually desired carbon-functionalized derivatives. It was discovered that such molecules, when treated with a catalytic amount of 4- (N, N-dimethylamino)pyridine (DMAP), rearrange quantitatively to the carbon acylated isomers.

These migrations, which are accompanied by a deep blue color, are proposed to involve a reactive intermediate. This intermediate, which is postulated as an ion pair charge transfer (IPCT) complex, has been closely studied in order to gain a better understanding of the …


Prediction Intervals For The Binomial Distribution With Dependent Trials, Florian Sebastian Rueck Jan 2003

Prediction Intervals For The Binomial Distribution With Dependent Trials, Florian Sebastian Rueck

Masters Theses

"A generalization of a prediction interval procedure for the binomial distribution to the case of the binomial distribution with dependent trials is considered. Several different methods have been developed for obtaining prediction intervals for the binomial distribution. An unpublished study by Vlieger and Samaranayake has shown that two of these methods achieve coverage probabilities close to nominal levels. The proposed method is an extension of one of these methods and is based on the maximum likelihood predictive density proposed by Lejeune and Faulkenberry. A simulation study was carried out to investigate the coverage probabilities of the proposed prediction bounds.

This …


Hybrid Data Mining Technique For Application In Geo-Chemical Data Analysis, Shipra Dutta Jan 2003

Hybrid Data Mining Technique For Application In Geo-Chemical Data Analysis, Shipra Dutta

Masters Theses

"Data mining is a very active research area, which has gained a lot of attention over the past few years for its applications in various fields ranging from stock forecasting to detecting damages in the structures like aircrafts. The use of data mining for applications in science and business has evoked a lot of interest in the researchers to explore the area further. In this research, a novel hybrid clustering architecture will be presented as a possible solution to classify the geo-chemical data obtained by conducting various direct and indirect tests on different sites. The fact that no single learning …


Synthesis And Characterization Of A Polypyridyl Ru(Ii)-Alloxazine Complex For Adsorption On Tio2-Coated Ito Electrodes, Manisha A. Patel Jan 2003

Synthesis And Characterization Of A Polypyridyl Ru(Ii)-Alloxazine Complex For Adsorption On Tio2-Coated Ito Electrodes, Manisha A. Patel

Masters Theses

TiO2-coated conducting glass electrodes can be modified by attachment of redox-active molecules to the TiO2 surface. This thesis describes the synthesis and characterization of a polypyridyl Ru(II) complex that can be covalently bound to a TiO2 surface through the carboxylate groups of 2,2'-bipyridine-4,4' -dicarboxylic acid, H2dcbpy. In addition, the bound complex contains a redox-active alloxazine derivative, pptd, which is capable of 2e-/2H+ transfers. Thus the TiO2-coated electrode is modified with a transition metal complex capable of shuttling H-atoms to substrates in solution. Synthesis of the PF6- salt …


The Synthesis Of 2-(1-Indenyl)-Phenol: A Potential Ligand For Metallocene Polymerization Catalysts; And, Ω-Iodoalkyl(Methyl) Malonate Esters: Synthesis And Application In Bioconjugate Chemistry, Sara E. Bendler Jan 2003

The Synthesis Of 2-(1-Indenyl)-Phenol: A Potential Ligand For Metallocene Polymerization Catalysts; And, Ω-Iodoalkyl(Methyl) Malonate Esters: Synthesis And Application In Bioconjugate Chemistry, Sara E. Bendler

Masters Theses

Chapter I:

Metallocene catalysis is an important division of polymerization chemistry. The design of appropriate ligands for metallocene catalysts has focused on stereochemical control and structural diversity. The synthesis of the potential ligand 2-(1-indenyl)-phenol has been developed. Indenyl phenol ligands offer advancements over cyclopentadienyl ligands because the steric and electronic properties of the catalyst could be tailored to suit individual polymerization reactions. 2-(1-Indenyl)-phenol was synthesized with an overall yield of 4% and characterized with 1H NMR and 13C NMR.

Chapter II:

A large percentage of breast malignancies overexpress the nuclear estrogen receptor (ER) protein. Binding to nuclear receptors …


Anthropogenic-Induced Changes To Weather And Climate: An Overview, Robert Cataneo Jan 2003

Anthropogenic-Induced Changes To Weather And Climate: An Overview, Robert Cataneo

Masters Theses

Human activities, since the beginning of the Industrial Revolution, have caused measurable and significant changes to local and regional weather and climate, as well as to global climate.

There is substantial evidence to show that anthropogenic influences have caused statistically significant changes to local and regional weather and climate, and have played a major role in the 0.6°C increase in global, low level temperature observed in the last 100 years. There is also an abundance of data that establishes a causal relationship between the 32% increase in atmospheric CO2 concentration that has occurred since the beginning of the Industrial …