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

Digital Commons Network™

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

LSU Historical Dissertations and Theses

Discipline
Keyword
Publication Year

Articles 1711 - 1740 of 7797

Full-Text Articles in Entire DC Network

Reactor Analysis Of Chemical Vapor Deposition Of Titanium Dioxide And Copper Thin Films., Wing-Cheong Gilbert Lai Jan 1994

Reactor Analysis Of Chemical Vapor Deposition Of Titanium Dioxide And Copper Thin Films., Wing-Cheong Gilbert Lai

LSU Historical Dissertations and Theses

A set of reactor models for chemical vapor deposition (CVD) of titanium dioxide films from titanium tetraisopropoxide (TTIP) in a vertical cold-wall CVD reactor has been developed. The effects of the carrier gas on the deposition of TiO$\sb2$ films were examined. The reaction mechanism proposed by the earlier workers in our group was used for the reactor modeling (Siefering and Griffin, 1990a; 1990b). The kinetic parameters were estimated from the reactor models at three levels of approximation; i.e., a lumped parameter (LP) model, a one-dimensional stagnation point flow reactor (1-D SPFR) model, and a full 2-D SPFR model. The 2-D …

Go to article

Strategic Adaptation In The Banking Industry: An Exploration Of The Antecedents And Consequences Of Strategic Change Following Deregulation., Elton L. Scifres Jr Jan 1994

Strategic Adaptation In The Banking Industry: An Exploration Of The Antecedents And Consequences Of Strategic Change Following Deregulation., Elton L. Scifres Jr

LSU Historical Dissertations and Theses

This dissertation examined the antecedents and consequences of strategic change in the commercial banking industry between 1980 and 1987. Based on a review of the literature, a conceptual model was developed that predicted change would be influenced by two factors, adaptive forces and inertial forces. Adaptive forces include two factors that have been hypothesized to encourage change, prior performance and slack resources. Inertial forces include two factors sometimes thought to inhibit change, organizational size and age. Change outcomes were predicted to be influenced by degree of change and moderated by adaptive and inertial forces. Guided by previous theoretical and empirical …

Go to article

Development Of Aluminum Tolerance In Rice (Oryza Sativa L.) Through Tissue Culture Techniques., Herry S. Utomo Jan 1994

Development Of Aluminum Tolerance In Rice (Oryza Sativa L.) Through Tissue Culture Techniques., Herry S. Utomo

LSU Historical Dissertations and Theses

Three tissue culture techniques, somaclone evaluation, in vitro screening of suspension cells, and in vitro screening of protoplasts were evaluated for their potential to produce aluminum (Al) tolerant rice. For somaclone evaluation, a collection of 9,000 rice somaclones was screened. After 11 days of germination in 200 uM Al, the length of the primary root was measured and used as the criterion for selection since a principal effect of Al toxicity is inhibition of root growth. Four superior lines were identified. Root length of the most tolerant line was 50% greater than its control following germination in screening solution. A …

Go to article

The Generalized Distributive Law As Tacit Knowledge In Algebra., Juanita Lavall Bates Jan 1994

The Generalized Distributive Law As Tacit Knowledge In Algebra., Juanita Lavall Bates

LSU Historical Dissertations and Theses

The purposes of this study were to investigate theories that explain why common errors of the type ($a \pm b)\sp{c} = a\sp{c} \pm b\sp{c}$ and $\root c \of {a \pm b} = \root c \of {a} \pm \root c \of {b}$ occur in algebra problem solving by novices; and to develop and assess techniques for remediating these errors. The meaning theory of learning (ML), procedural learning theory (PL), and implicit structure learning theory (ISL) are alternative frameworks for the explanation of the errors. The ML theory hypothesizes that experts have rich semantic connections to the procedures and symbols of algebra, …

Go to article

Theoretical And Experimental Modeling Of Removing Contaminants From Soils By An Electric Field., Akram Nimer Alshawabkeh Jan 1994

Theoretical And Experimental Modeling Of Removing Contaminants From Soils By An Electric Field., Akram Nimer Alshawabkeh

LSU Historical Dissertations and Theses

A mathematical model is formulated for multicomponent transport of reactive species under an electric field. A set on differential and algebraic equations is developed for transport of fluid, charge, and species in a saturated soil under coupled hydraulic, electric, and chemical potential gradients. An iterative scheme is chosen in solution of a system of differential and algebraic equations. Six differential equations and four algebraic equations are used to model transport of $Pb\sp{2+}$, $H\sp+$, $OH\sp-$, $NO3\sp-$, the associated chemical reactions, electric potential and the hydraulic head across the electrodes. Finite Element Method is used in space discretization. Finite difference technique is …

Go to article

Development Of A Body Image Assessment Procedure For Children And Pre-Adolescents., Staci Veron Guidry Jan 1994

Development Of A Body Image Assessment Procedure For Children And Pre-Adolescents., Staci Veron Guidry

LSU Historical Dissertations and Theses

Eating disorders have been researched extensively among adult, and, more recently, among adolescent populations. Body image disturbance is included as a diagnostic criterion for anorexia nervosa and bulimia nervosa, and has been postulated as a central characteristic of the eating disorders. Researchers have identified eating disorders among prepubertal children; therefore, there is a need for the development of reliable and valid measures of eating disorders and body image in children. In this investigation, a total of 257 children in grades 3 through 7 completed the Children's Eating Attitudes Test, Children's Depression Inventory, Piers-Harris Children's Self Concept Scale physical appearance and …

Go to article

A Heuristic Approach For Shortest Path Problem With Rectilinear Obstacles., Joon Shik Lim Jan 1994

A Heuristic Approach For Shortest Path Problem With Rectilinear Obstacles., Joon Shik Lim

LSU Historical Dissertations and Theses

This dissertation presents new heuristic search algorithms, the Guided Minimum Detour (GMD) algorithm and the Line-by-Line Guided Minimum Detour (LGMD) algorithm for searching rectilinear ($L\sb1$) shortest paths in the presence of rectilinear obstacles. The GMD algorithm combines the best features of maze-running algorithms and line-search algorithms. The LGMD algorithm is a modification of the GMD algorithm that improves on efficiency using line-by-line extensions. Our GMD and LGMD algorithms always find a rectilinear shortest path using the guided $A\sp*$ search method without constructing a connection graph that contains a shortest path. The GMD algorithm and the LGMD algorithm can be implemented …

Go to article

Surplus Labor And Mobility In Hebei, China: An Evaluation Of The Litu Bu Lixiang Approach., Chunxiao Li Jan 1994

Surplus Labor And Mobility In Hebei, China: An Evaluation Of The Litu Bu Lixiang Approach., Chunxiao Li

LSU Historical Dissertations and Theses

The most fundamental economic reforms were introduced within the rural areas in China during the 1980s. The resulting greater efficiency in production, and the continued population growth have combined to result in a vast number of surplus laborers in rural areas. While concerned about the rural surplus labor problem, the Chinese government also determined to avoid mass rural-urban migration. In 1984, the Chinese Government promulgated a policy called litu bu lixiang (leave the land, but not the countryside). The basic idea is to absorb surplus labor through the retention of labor in the rural areas by creating non-agricultural opportunities. The …

Go to article

The Development And Evaluation Of Impedance Technology To Determine The Quality Of Shrimp And Catfish., Patti Lynn Wiese Lehigh Jan 1994

The Development And Evaluation Of Impedance Technology To Determine The Quality Of Shrimp And Catfish., Patti Lynn Wiese Lehigh

LSU Historical Dissertations and Theses

Impedance technology is currently used as a measurement of microbial activity. The purpose of the current study was to determine the feasibility of utilizing impedance technology to evaluate the quality of white shrimp (marine species) and channel catfish (freshwater species). Impedance analysis measurements (I-values) of raw shrimp increased for samples stored at 5, 25, and 35$\sp\circ$C; however, control samples stored at $-$20$\sp\circ$C displayed no significant changes in I-values. I-values from thermally processed shrimp had no direct relationship with odor scores, increased storage time, or increased storage temperature. It was concluded that while impedance measurements were able to indicate the degree …

Go to article

Investigations On Insecticide Resistance In Tobacco Budworm, Heliothis Virescens (F.), And Boll Weevil, Anthonomus Grandis Grandis Boheman, In The Mid-South., Scott Hamilton Martin Jan 1994

Investigations On Insecticide Resistance In Tobacco Budworm, Heliothis Virescens (F.), And Boll Weevil, Anthonomus Grandis Grandis Boheman, In The Mid-South., Scott Hamilton Martin

LSU Historical Dissertations and Theses

Topical bioassays were conducted in 1991 to develop dose-mortality lines for the LSU laboratory reference colony (LSU-LAB) and field-collected colonies of tobacco budworm, Heliothis virescens (F.), from Louisiana, Mississippi and Texas. Field-collected colonies exhibited resistance to cypermethrin (1-41x), profenofos and sulprofos (1-8x), methomyl (2-6x) and no resistance to endosulfan compared to the LSU-LAB colony. Diagnostic dose bioassays were developed to facilitate rapid testing of field-collected colonies for resistance to insecticides. These diagnostic dose bioassays were conducted in 1992 and 1993 on the LSU-LAB colony, a North Carolina laboratory reference colony and field-collected colonies from Louisiana, Oklahoma and Texas. Significant (P …

Go to article

Latitudinal Gradients In Temperate And Tropical Seasonal Forests., Martin Francis Quigley Jan 1994

Latitudinal Gradients In Temperate And Tropical Seasonal Forests., Martin Francis Quigley

LSU Historical Dissertations and Theses

In an analysis of latitudinally replicated one hectare samples, nine seasonal forests of the temperate and tropical Americas were found to be very similar in biomass, stratification and patterns of spatial dispersion, regardless of taxonomic composition or relative stem density. Neither basal area nor relative size class distributions of trees differed significantly among latitudes from the equator to 40$\sp\circ$ north. While overall plant density was greater in tropical forests, the numbers and composition within individual strata--shrub layer, subcanopy, canopy, and liana--interacted independently and significantly with latitude. Understory populations were denser and more speciose at middle latitudes, in forests frequently affected …

Go to article

Titanocene/Dna Binding And The Synthesis And Characterization Of Bridged Cyclopentadienes For The Preparation Of Novel Titanocenes., Tamara Renee Schaller Jan 1994

Titanocene/Dna Binding And The Synthesis And Characterization Of Bridged Cyclopentadienes For The Preparation Of Novel Titanocenes., Tamara Renee Schaller

LSU Historical Dissertations and Theses

Titanocene dichloride, a potent antitumor agent, forms a DNA-titanium adduct with Salmon Sperm DNA in 10 mM sodium perchlorate solutions ranging from pH 5 to 8.5. At physiological pH, titanocene dichloride undergoes base catalyzed hydrolysis in which the cyclopentadienyl ligands are susceptible to substitution. In chapter one of this dissertation the results of inductively coupled plasma and scintillation counting analysis of the DNA-titanium adduct formed by in vitro treatment of a DNA solution with tritiated titanocene dichloride indicate the formation of a DNA-Cp$\sb2$Ti adduct at pH 5.3 and a DNA-CpTi adduct at pH 7.0. Titanocenes prepared from bridged cyclopentadienyl ligands …

Go to article

The Production And Characterization Of Alginate Produced By Pseudomonas Syringae., Richard David Ashby Jan 1994

The Production And Characterization Of Alginate Produced By Pseudomonas Syringae., Richard David Ashby

LSU Historical Dissertations and Theses

Alginate has many industrial uses because of its unique colloidal behavior, and its ability to thicken, stabilize, emulsify, suspend, form films, and produce gels. Currently, all commercial alginate comes from brown algae, where it exists naturally as a structural material. Many different types of brown algae produce alginate but it can only be obtained in sufficient quantity and quality from a limited number of species. On the basis of location, at least half of the world's resources of this polymer are potentially at risk due either to political instability or industrial pollution. Bacteria provide a potentially unlimited alternate source for …

Go to article

Quantitative Models For The Transition To Just-In-Time Purchasing., Pamela Lynne Anders Jan 1994

Quantitative Models For The Transition To Just-In-Time Purchasing., Pamela Lynne Anders

LSU Historical Dissertations and Theses

Purchasing is a critical, external element of the Just-In-time (JIT) production system. JIT purchasing calls for small delivery quantities which arrive on time, with the quality and quantity required. Economic order quantity models which are adjusted for multiple deliveries or consider the cooperation between the purchaser and the supplier have been published in the literature. The JIT philosophy emphasizes both of these elements. We provide a model for single sourcing which incorporates multiple deliveries and cooperation for the case where there is a single reliable supplier. We call this perfect coordination. The transition to JIT, currently occurring in many companies …

Go to article

There's No Place Like Home: An Analysis Of The Rhetoric Of Homelessness In A Judicial Opinion, An Advocate's Congressional Testimony, And Testimonial Narratives By The Homeless., Niki L. Young Jan 1994

There's No Place Like Home: An Analysis Of The Rhetoric Of Homelessness In A Judicial Opinion, An Advocate's Congressional Testimony, And Testimonial Narratives By The Homeless., Niki L. Young

LSU Historical Dissertations and Theses

The central question this dissertation seeks to answer is: What does homelessness mean, and how is that meaning rhetorically constructed? What homelessness means is not fixed nor static, but varies with use. To discover and develop these different meanings, three sets of data were examined: a judicial opinion, an advocate's congressional testimony, and testimonial narratives by the homeless. This data includes rhetoric produced from three distinct points of view--one that is sympathetic to the homeless, one that is hostile to the homeless, and one that has experienced homelessness. A Burkean methodology was employed, supplemented, where appropriate, with insights from postmodern …

Go to article

A Rules Based Approach To Analyze Data Dependent Transformation Strategies Of A Supercompiler For Parallel Computers., James Woodson Mcguffee Jan 1994

A Rules Based Approach To Analyze Data Dependent Transformation Strategies Of A Supercompiler For Parallel Computers., James Woodson Mcguffee

LSU Historical Dissertations and Theses

A supercompiler is a program that attempts to automatically restructure serial code into an equivalent parallel form. This restructuring is achieved through the application of various transformation strategies designed to remove data dependences. A data dependence is a relation between two programming statements that prevent those two statements from being executed in parallel. This research develops a rules based system to analyze the various data dependent transformation strategies of a supercompiler for parallel computers. With the information obtained from user input and the automated analysis of a program segment, this rules based analysis will be able to determine which of …

Go to article

Immunological And Developmental Factors Affecting The Efficacy Of In Vitro Fertilization, Embryo Culture And Embryo Transfer In The Domestic Cat., William Frederick Swanson Jan 1994

Immunological And Developmental Factors Affecting The Efficacy Of In Vitro Fertilization, Embryo Culture And Embryo Transfer In The Domestic Cat., William Frederick Swanson

LSU Historical Dissertations and Theses

Developmental and immunological factors affecting the efficacy of assisted reproduction for domestic and endangered nondomestic felid species were investigated. In the first study, domestic cats exhibited decreased (P $<$ 0.05) numbers of follicles and maturity of oocytes following repeated treatments, at short intervals (44-50 days), with a combination regimen of equine chorionic gonadotropin (eCG) and human chorionic gonadotropin (hCG). Queens had elevated titers of eCG/hCG-binding immunoglobulins compared with male cats and naive queens, and these immunoglobulins attenuated eCG and hCG bioactivity in mouse ovarian stimulation assays. However, refractory queens appeared to cycle naturally and were responsive to an alternative exogenous gonadotropin, porcine follicle stimulating hormone (pFSH). In the second study, queens exhibited individual variability in immune responses to eCG and hCG, and this variability affected (P $$ 0.05) when longer intervals (130-135 days) were used between successive eCG/hCG treatments. In the third study, the effects of eCG and hCG on the suitability of the maternal environment were investigated. Following intramuscular injection, eCG had an elimination half-life of 24 to 48 hours and, 5 and 15 days after follicular aspiration, eCG/hCG-treated queens had formed multiple ancillary follicles and secondary corpora lutea (CL), respectively. Treatment with antisera against eCG/hCG slowed (P $$ 0.05) serum progesterone levels or decrease (P $>$ 0.05) the number of secondary ovarian structures. In the fourth study, developmental requirements of IVF-derived cat embryos were examined, with the emphasis on energy sources, media complexity and tissue co-culture and temporal variations in these factors. Embryos developed equally well (P $>$ 0.05) to morulae in simple media containing either glucose or glutamine, but blastocyst formation and embryo cell number were decreased (P $<$ 0.05) when glucose was present during the early culture period. Co-culture of embryos on oviductal cell monolayers decreased (P $<$ 0.05) fertilization and blastocyst formation. In the final study, a transcervical technique for embryo transfer was developed and used successfully to produce viable offspring in the domestic cat.

Go to article

Utility Of Remote Sensing Technology In Wetland Soil And Gas Flux Studies., Ramona Eva Pelletier Travis Jan 1994

Utility Of Remote Sensing Technology In Wetland Soil And Gas Flux Studies., Ramona Eva Pelletier Travis

LSU Historical Dissertations and Theses

Much of the traditionally used remotely sensed data is surface-oriented, which places some limits on its utility in wetland soil studies. In wetland environments the sediment surface is often obscured by vegetation and/or by water making the soil difficult to view. This study examines the possible utility of remotely sensed data from selected regions of the EM spectrum for wetland soil and gas flux studies. The visible, near-infrared, mid-infrared, thermal, and microwave regions (all mostly surface-oriented); and the ground penetrating radar (VLF) and inductive EM (ULF) regions (mostly subsurface-oriented) were investigated and example wetland soil applications demonstrated. Study sites ranged …

Go to article

Three-Dimensional Radiative Transfer On A Massively Parallel Computer., Horst Michael Vath Jan 1994

Three-Dimensional Radiative Transfer On A Massively Parallel Computer., Horst Michael Vath

LSU Historical Dissertations and Theses

We perform three-dimensional radiative transfer calculations on the MasPar MP-1, which contains 8192 processors and is a single instruction multiple data (SIMD) machine, an example of the new generation of massively parallel computers. To make radiative transfer calculations efficient, we must re-consider the numerical methods and methods of storage of data that have been used with serial machines. We developed a numerical code which efficiently calculates images and spectra of astrophysical systems as seen from different viewing directions and at different wavelengths. We use this code to examine a number of different astrophysical systems. First we image the HI distribution …

Go to article

A New Method For Efficient Parallel Solution Of Large Linear Systems On A Simd Processor., Okon Hanson Akpan Jan 1994

A New Method For Efficient Parallel Solution Of Large Linear Systems On A Simd Processor., Okon Hanson Akpan

LSU Historical Dissertations and Theses

This dissertation proposes a new technique for efficient parallel solution of very large linear systems of equations on a SIMD processor. The model problem used to investigate both the efficiency and applicability of the technique was of a regular structure with semi-bandwidth $\beta,$ and resulted from approximation of a second order, two-dimensional elliptic equation on a regular domain under the Dirichlet and periodic boundary conditions. With only slight modifications, chiefly to properly account for the mathematical effects of varying bandwidths, the technique can be extended to encompass solution of any regular, banded systems. The computational model used was the MasPar …

Go to article

Intraspecific Variation In The Response Of Baldcypress (Taxodium Distichum) Seedlings To Salinity., James Andrew Allen Jan 1994

Intraspecific Variation In The Response Of Baldcypress (Taxodium Distichum) Seedlings To Salinity., James Andrew Allen

LSU Historical Dissertations and Theses

This study evaluated genotypic variation in responses of baldcypress (Taxodium distichum) seedlings to combined flooding and salinity stress. Two experiments form the core of this dissertation. In the first experiment, seedlings of 15 open-pollinated families of baldcypress were exposed to combined salinity and flooding stress under greenhouse conditions. Ten of the families were from coastal locations that were slightly brackish. The other families were from freshwater locations. Five salinity levels were investigated--0, 2, 4, 6, and 8 g l$\sp{-1}$ artificial seawater--all with shallow flooding. Substantial variation was found among salinity levels and families for most of the response variables assessed. …

Go to article

Continuous Variation In Ellen Taaffe Zwilich's "Intrada", And "Generations", An Original Composition For Soprano, Tenor, And Orchestra., George Albert Benner Jan 1994

Continuous Variation In Ellen Taaffe Zwilich's "Intrada", And "Generations", An Original Composition For Soprano, Tenor, And Orchestra., George Albert Benner

LSU Historical Dissertations and Theses

This dissertation divides into two parts. The first part illustrates certain traits of Ellen Taaffe Zwilich's neo-Romantic style by analyzing a single piece, Intrada (1983) for five players. The analysis is in three main sections. The first section discusses how Zwilich's background might have influenced her post-1979 writing, particularly her interest in continuous variation through the writings of Schoenberg and her studies with Sessions, and Carter. The second section focuses on Intrada and Zwilich's use of continuous variation. This section also analyzes cyclical elements and considers various older principles of melodic and pitch recurrence while determining the form of this …

Go to article

A Relaxation Scheme For Mesh Locality In Computer Vision., Weian Deng Jan 1994

A Relaxation Scheme For Mesh Locality In Computer Vision., Weian Deng

LSU Historical Dissertations and Theses

Parallel processing has been considered as the key to build computer systems of the future and has become a mainstream subject in Computer Science. Computer Vision applications are computationally intensive that require parallel approaches to exploit the intrinsic parallelism. This research addresses this problem for low-level and intermediate-level vision problems. The contributions of this dissertation are a unified scheme based on probabilistic relaxation labeling that captures localities of image data and the ability of using this scheme to develop efficient parallel algorithms for Computer Vision problems. We begin with investigating the problem of skeletonization. The technique of pattern match that …

Go to article

A Study Of The Abundances Of Light Isotopes In Cosmic Rays With A Superconducting Magnet Instrument., Michal Lijowski Jan 1994

A Study Of The Abundances Of Light Isotopes In Cosmic Rays With A Superconducting Magnet Instrument., Michal Lijowski

LSU Historical Dissertations and Theses

The balloon-borne Superconducting Magnet Instrument for Light Isotopes flew for the second time on July 24-25, 1991 at the altitude of 36 km during conditions of extremely high solar modulation. The detector was designed to measure the charge, rigidity, and velocity of cosmic rays heavier than hydrogen within the kinetic energy range 100-2000 MeV/nucleon. The helium spectrum measured over this wide energy range is consistent with an interstellar helium spectrum expressed as a power law in the rigidity with spectral index of $-$2.68 and modulated to a level given by the solar modulation parameter $\phi$ = 1.5 GV. The $\sp2$H/$\sp4$He …

Go to article

Ostracoda Of The Latest Cretaceous And Earliest Tertiary Of The Gulf Coastal Plain: Biostratigraphy, Paleoenvironments, And Systematics., Kasana Pitakpaivan Jan 1994

Ostracoda Of The Latest Cretaceous And Earliest Tertiary Of The Gulf Coastal Plain: Biostratigraphy, Paleoenvironments, And Systematics., Kasana Pitakpaivan

LSU Historical Dissertations and Theses

Examination of the Ostracoda of the latest Cretaceous and earliest Tertiary of the Gulf Coastal Plain indicates that this microscopic crustacean is a practical, valuable tool for biostratigraphy and paleoenvironmental interpretation in this major geologic and geographic province. The newly established Veenia parallelopora Zone, an ostracode interval zone for the late Maastrichtian, allows correlation of the uppermost Cretaceous units across the Gulf Coastal Province. Veenia parallelopora, Brachycythere foraminosa, and Veenia adkinsi are characteristic species of this zone. The uppermost, latest Maastrichtian, part of this zone can be recognized by the presence of these three species plus Antibythocypris johnsoni, Brachycythere ovata …

Go to article

A Directed Hypergraph Approach For The Verification Of Rule-Based Expert Systems., Mysore Ramaswamy Jan 1994

A Directed Hypergraph Approach For The Verification Of Rule-Based Expert Systems., Mysore Ramaswamy

LSU Historical Dissertations and Theses

Rule-based representation techniques have become popular for storing and manipulation of domain knowledge in expert systems. It is important that systems using such a representation are verified for accuracy before implementation. In recent years, graphical techniques have been found to provide a good framework for the detection of errors that may appear in a rule base. In this dissertation, we develop a technique that uses a directed hypergraph to accurately detect all the different types of errors that appear in a rule base. This technique overcomes limitations of existing graphical techniques that are unable to accurately detect all the errors …

Go to article

Photoemission Studies Of Electronic Dispersion In Metals And Thin Film Systems., Zhe Qu Jan 1994

Photoemission Studies Of Electronic Dispersion In Metals And Thin Film Systems., Zhe Qu

LSU Historical Dissertations and Theses

We have studied the electronic dispersion of Cu and the Cu/Ru(0001) bimetallic system using photoelectron spectroscopy. Images of electron emission from Cu(100), Cu(111), and Cu/Ru(0001) have been obtained using an ellipsoidal-mirror analyzer (EMA). This energy analyzer collects photoemitted electrons over a large solid angle, preserving their angular information and providing an image of intensity versus emission angle. The images provide direct information on band dispersion. The surface state of Cu(111) was measured using the EMA at different binding energies. By combining these images, we have obtained the surface state dispersion in three dimensional E vs k space. Our results are …

Go to article

Dynamic Behavior Of Magnetic Latex Particles And Polyelectrolytes., Daewon Sohn Jan 1994

Dynamic Behavior Of Magnetic Latex Particles And Polyelectrolytes., Daewon Sohn

LSU Historical Dissertations and Theses

The dynamic behavior of magnetic latex particles has been explored. Polarized and depolarized dynamic light scattering from binary and ternary systems of these particles have provided rotational and translational diffusion coefficients. Microscopic views of rotational and translational diffusion of these particles are compared with macroscopic viscosity from the Stokes-Einstein equation (Chapter 2). The polymeric stabilization of magnetic latex particles has also been investigated by static and dynamic light scattering. Using the optical anisotropy of magnetic latex particles, the translational and rotational diffusion coefficients of the particles under various salt conditions were determined. The stability of the superparamagnetic latex particles depends …

Go to article

An Incremental Navigation Localization Methodology For Application To Semi-Autonomous Mobile Robotic Platforms To Assist Individuals Having Severe Motor Disabilities., Daryl Devon Thomas Jan 1994

An Incremental Navigation Localization Methodology For Application To Semi-Autonomous Mobile Robotic Platforms To Assist Individuals Having Severe Motor Disabilities., Daryl Devon Thomas

LSU Historical Dissertations and Theses

In the present work, the author explores the issues surrounding the design and development of an intelligent wheelchair platform incorporating the "semi-autonomous" system paradigm, to meet the needs of individuals with severe motor disabilities. The author presents a discussion of the problems of navigation that must be solved before any system of this type can be instantiated, and enumerates the general design issues that must be addressed by the designers of systems of this type. This discussion includes reviews of various methodologies that have been proposed as solutions to the problems considered. Next, the author introduces a new navigation method, …

Go to article

Extremely High Field Nmr Techniques And Instrumentation For The Study Of Catalysts And Materials., Xiao Wu Jan 1994

Extremely High Field Nmr Techniques And Instrumentation For The Study Of Catalysts And Materials., Xiao Wu

LSU Historical Dissertations and Theses

The main goal of the research presented in this dissertation is to develop and apply solid-state nuclear magnetic resonance (NMR) techniques to study catalytic materials. Several solid state NMR techniques were developed and have been applied to a series of catalyst systems. The construction and operation of several NMR spectrometers, and the design of NMR probes are discussed. The most novel is a broadband pulsed NMR spectrometer with digital phase shifting and a 0 to 18 Tesla magnet. The development and construction of a field-swept NMR spectrometer is described in detail. This instrument provides a means of acquiring high-quality solid …

Go to article

First Prev Next Last