Physical Sciences and Mathematics Commons^™

Portable X-Ray Fluorescence Measurement Viability In Organic Rich Soils: Pxrf Response As A Function Of Organic Matter Presence, Roozbeh Ravansari

Wayne State University Theses

Portable X-Ray fluorescence provides a cost effective method for producing rapid geochemical data. With advancements in X-Ray generation and detection technology, pXRF has become feasible for use on pedologic materials. Factors affecting pXRF soil measurements such as heterogeneity, moisture content, object geometry, and matrix interferences are widely recognized. However, the influence of organic matter on pXRF soil measurements is poorly understood.

This study examined the influence of organic matter fraction on pXRF trace metal measurements in a soil matrix. Incremental addition of three organic matter surrogates (cellulose, graphite powder, and confectioner’s sugar) was used to investigate the influence of increasing …

Novel Design And Synthesis Of Transition Metal Hydroxides And Oxides For Energy Storage Device Applications, Peifeng Li

Wayne State University Theses

Supercapacitors (SCs) and Li-ion batteries (LIBs) are two types of important electrical energy storage devices with high power density and high energy density respectively. However, to satisfy the increasing demand of high-performance energy storage devices, the energy density of SCs and power/energy densities of LIBs have to be further improved. The exploration, research, and development of electrode materials with high-performance for applications in SCs and LIBs are still needed to meet the ever-increasing demand on energy and power densities. Herein, the amorphous Ni-Co-Mo ternary hydroxides nanoflakes for SCs and oxides nanoflakes for LIBs with ultrathin stature, abundant open spaces, and …

A Topological Study Of Stochastic Dynamics On Cw Complexes, Michael Joseph Catanzaro

Wayne State University Dissertations

In this dissertation, we consider stochastic motion of subcomplexes of a CW complex, and explore the implications on the underlying space. The random process on the complex is motivated from Ito diffusions on smooth manifolds and Langevin processes in physics. We associate a Kolmogorov equation to this process, whose solutions can be interpretted in terms of generalizations of electrical, as well as stochastic, current to higher dimensions. These currents also serve a key function in relating the random process to the topology of the complex. We show the average current generated by such a process can be written in a …

Essays On Oil Price Volatility And Irreversible Investment, Daniel Joseph Pastor

Wayne State University Dissertations

In chapter 1, we provide an extensive and systematic evaluation of the relative

forecasting performance of several models for the volatility of daily spot

crude oil prices. Empirical research over the past decades has uncovered

significant gains in forecasting performance of Markov Switching GARCH

models over GARCH models for the volatility of financial assets and crude

oil futures. We find that, for spot oil price returns, non-switching models

perform better in the short run, whereas switching models tend to do better

at longer horizons.

In chapter 2, I investigate the impact of volatility on firms' irreversible investment decisions using real …

Estimating Effects Of Non-Normality In Assessing Structural Equation Model Fit For Use Of Physical Science Data, Sarah Rose

Wayne State University Dissertations

ABSTRACT

ESTIMATING EFFECTS OF NON-NORMALITY IN ASSESSING

STRUCTURAL EQUATION MODEL FIT FOR USE OF PHYSICAL SCIENCE DATA

by

SARAH ALTA ROSE

May 2016

Advisor: Dr. Barry Markman

Major: Education (Evaluation and Research)

Degree: Doctor of Philosophy

The purpose of this study was to evaluate the sensitivity of selected fit index statistics in determining model fit when the distribution varied from normality, as is typically true of data research for the physical sciences. SEM is a popular statistical method and is used in many physical and social behavioral science research projects; however, the sensitivity of the model fit indices when normality …

Evaluating Recruitment Of American Eel, Anguilla Rostrata, In The Potomac River (Spring 2016), Troy D. Tuckey, Mary C. Fabrizio

Reports

American Eel (Anguilla rostrata) is a valuable commercial species along the Atlantic coast of North America from New Brunswick to Florida. Landings from Chesapeake Bay typically represent 60% of the annual United States commercial harvest (ASMFC 2012). American Eel is also important to the recreational fishery as it is often used live as bait for Striped Bass (Morone saxatilis) and Cobia (Rachycentron canadum). In 2012, Chesapeake Bay commercial landings of American Eel (771,536 lbs) were 72% of the U.S. landings (personal communication from the National Marine Fisheries Service, Fisheries Statistics Division). Since the 1980s, harvest along the U.S. Atlantic Coast …

Vertical One-Dimensional (1-D) Simulations Of Horizontal Velocity Profiles, Jerome P.Y. Maa, Jian Shen, Xiaoteng Shen, Shao Yuyang

Reports

Details of a vertical 1-D hydrodynamic model to simulate the horizontal velocity profiles for tidal estuarial flows with possible stratifications caused by salinity or Suspended Sediment Concentration (SSC) are presented. The standard 2nd order k-ε model was implemented to address the turbulent flow with possible stratification effects. Simulation results are verified with two field measurements for steady nonstratified flows and a field measurement for tidal estuary non-stratified flow. The stratification effect of salinity and suspended sediment concentration are also checked with the following descriptions: “Salinity stratification will change the typical logarithmic velocity profile to a linear profile for most of …

City Of Chesapeake, Virginia Shoreline Inventory Report Methods And Guidelines, Marcia Berman, Karinna Nunez, Sharon Killeen, Tamia Rudnicky, Julie Bradshaw, David Stanhope, Karen Duhring, Kallie Brown, Jessica Hendricks, David Weiss, Carl Hershner

Reports

The 2016 Inventory for City of Chesapeake was generated using on-screen, digitizing techniques in ArcGIS® - ArcMap v10.2.2 while viewing conditions observed in Bing high resolution oblique imagery, Google Earth, and 2013 imagery from the Virginia Base Mapping Program (VBMP). Four GIS shapefiles are developed. The first describes land use and bank conditions (Chesapeake_lubc_2016). The second portrays the presence of beaches (Chesapeake_beaches_2016). The third reports shoreline structures that are described as arcs or lines (e.g. riprap) (Chesapeake_sstru_2016). The final shapefile includes all structures that are represented as points (e.g. piers) (Chesapeake_astru_2016). The metadata file accompanies the shapefiles and defines attribute …

Purin-6-One Derivatives As Phosphodiesterase-2 Inhibitors, Wei Yuan, Xin-Yun Zhao, Xi Chen, Chang-Guo Zhan

Pharmaceutical Sciences Faculty Publications

A series of purin-6-one derivatives were synthesized, and their in vitro inhibitory activity against phosphodiesterase-2 (PDE2) was evaluated by using a fluorescence polarization assay. Three compounds, that are, 2j, 2p, and 2q, showed significant inhibitory activity against PDE2 with IC₅₀ values of 1.73, 0.18, and 3.43 μM, respectively. Structure-activity relationship (SAR) analysis was performed to explore the relationship between the chemical structures of these compounds and their inhibitory activity. Compounds 2j, 2p, and 2q were further selected for molecular docking study. The docking results suggested that these ligands bind with hydrophobic pockets of …

Exploration Of Curvature Through Physical Materials, Lucinda-Joi Chu-Ketterer

Pitzer Senior Theses

Parametric equations are commonly used to describe surfaces. Looking at parametric equations does not provide tangible information about an object. Thus through the use of physical materials, an understanding of the limitations of the materials allows someone to gain a broader understanding of the surface. A M$\ddot{o}$bius strip and Figure 8 Klein bottle were created through knitting due to the precision and steady increase in curvature allowed through knitting. A more standard Klein bottle was created through crochet due to the ease in creating quick increases in curvature. Both methods demonstrate the change in curvature for both surfaces where the …

A Step In The Right Direction: Streambank Restoration Efforts At The Botanical Garden Of The Ozarks, Dylan S. Milholen, Madison Brown, Steven Thao, Lisa S. Wood

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

The Botanical Garden of the Ozarks (BGO) is a unique destination in Northwest Arkansas that draws more than 80,000 visitors a year. While the BGO manages low-input practices, run-off from pesticide application and synthetic fertilizers containing phosphorus and nitrogen are of concern to water quality, habitat, and overall ecological interactions of the BGO streambanks and adjacent Hilton Creek, which flows directly into Lake Fayetteville. One way to reduce pollution to waterbodies is through the use of riparian buffers. This project sought to establish a riparian buffer immediately adjacent to a portion of Hilton Creek in an effort to improve ecological …

Lower Mississippian Chert Development, Southern Midcontinent Region, J. M. Cains, A. Potra, E. D. Pollock

Journal of the Arkansas Academy of Science

The Lower Mississippian Boone Formation is a chert-bearing, fossiliferous limestone typically 100-115m. thick forming the Springfield Plateau across the tri-state region of northwestern Arkansas, southwestern Missouri, and northeastern Oklahoma. The Boone represents the maximum flooding, highstand, and regressive intervals of a single, third order transgressive-regressive carbonate cycle bounded by regional unconformities. Two types of chert occur in this formation, and provide the basis for subdivision of the Boone into informal lower and upper members in northern Arkansas. The lower Boone represents early Osagean maximum flooding conditions and consists of calcisiltites with interbedded dark, nodular chert. This chert exhibits compaction phenomena …

Early Cementation Of The Short Creek Oolite Member, Boone Formation (Osagean, Lower Mississippian), Northern Arkansas, K. A. Jayne, A. K. Chandler, W. L. Manger

Journal of the Arkansas Academy of Science

The Short Creek Oolite is the only formally named member of the Boone Formation in northern Arkansas. It lacks bedding features, and oolith concentrations that would suggest a shoal environment, and it occurs at variable stratigraphic horizons within the upper Boone Formation consistent with episodic deposition as grainflow slurries. As with modern oolite examples, such as Joulters Cays, Bahamas, the Short Creek preserves numerous intraclasts, and at least one large olistolith indicating an early cementation history.

Comparison Of The Elemental Geochemistry Of The Arkansas Novaculite And The Boone Chert In Their Type Regions, Arkansas, J. Philbrick, E. Pollock, A. Potra

Journal of the Arkansas Academy of Science

The name Arkansas Novaculite was proposed by A.H. Purdue, 1909 to replace the name Arkansas Stone assigned by L. S. Griswold, 1892, but deemed too generic, to an interval of Early Devonian-Early Mississippian, very fine-grained, even textured, siliceous sedimentary rock famous for use as whetstones. The interval is exposed along the margins of the Benton Uplift, south flank of the Ouachita Mountains, west-central Arkansas, where it reaches a maximum thickness of 243.8 m (800 ft). The Arkansas Novaculite comprises informal lower and upper members characterized by massive beds of nearly pure novaculite, separated by a shale-bearing middle member that spans …

Water-Quality Effects On Phytoplankton Species And Density And Trophic State Indices At Big Base And Little Base Lakes, Little Rock Air Force Base, Arkansas, June Through August, 2015, L. J. Driver, B. G. Justus

Journal of the Arkansas Academy of Science

Big Base and Little Base Lakes are located on Little Rock Air Force Base, Arkansas, and their close proximity to a dense residential population and an active military/aircraft installation make the lakes vulnerable to water-quality degradation. The U.S. Geological Survey (USGS) conducted a study from June through August 2015 to investigate the effects of water quality on phytoplankton species and density and trophic state in Big Base and Little Base Lakes, with particular regard to nutrient concentrations. Nutrient concentrations, trophic-state indices, and the large part of the phytoplankton biovolume composed of cyanobacteria, indicate eutrophic conditions were prevalent for Big Base …

Impact Of Climate Variations On Soybean Yield In Eastern Arkansas: 1960-2014, J. W. Magugu, S. Feng, Q. Huang, K. Luthra

Journal of the Arkansas Academy of Science

Climate is the major factor affecting crop production; therefore, various agro-meteorological indicators have been frequently used to evaluate the impact of climate on crop production. In this study, we examined the temporal variations of agrometeorological indicators (growing degree days, total precipitation, dry spells and drought indices) during 1960-2014 and their impact on soybean yields in East Arkansas. Results show an increasing trend in growing degree days (GDDs) and dry spells, though the total precipitation during the soybean growing season remained nearly unchanged during the study period. Generally, GDDs and dry spells show a strong correlation with yields. We also evaluated …

A Bond Length – Bond Valence Relationship For Carbon – Nitrogen Bonds, C. Harris, F. D. Hardcastle

Journal of the Arkansas Academy of Science

In a recent study, Pauling’s relationship between bond length and valence was derived along with a definition for his fitting parameter b that incorporates the orbital exponents for each atom contributing to the bond of interest. The values of b for various bonds, including C-N bonds, were calculated using the orbital exponent data. In this study, Pauling’s correlation between bond length and bond valence, as well as his valence sum rule, were used with the recently-derived definition for b in order to produce a relationship specifically applicable to C-N bonds. The resulting equation was checked against published x-ray diffraction data …

Electron Shock Waves With A Large Current Behind The Shock Front, H. D. Newberry, M. Hemmati, H. D. Moore, K. Ledbetter, M. W. Bowman

Journal of the Arkansas Academy of Science

The propagation of breakdown waves in a gas, which is primarily driven by electron gas pressure, is described by a one-dimensional, steady-state, three-component (electrons, ions, and neutral particles) fluid model. We consider the electron gas partial pressure to be much larger than that of the other species and the waves to have a shock front. Our set of equations consists of the equations of conservation of the flux of mass, momentum, and energy coupled with Poisson’s equation. This set of equations is referred to as the electron fluid dynamical equations. In this study we are considering breakdown waves propagating in …

Lithologic Character Of The Paleozoic Sandstone Succession, Southern Ozark Region, Arkansas, And Missouri, E. C. Bello

Journal of the Arkansas Academy of Science

Sandstones comprise nearly half of the Paleozoic (Upper Cambrian-Middle Pennsylvania) lithostratigraphic succession in the southern Ozark region of northern Arkansas and southern Missouri. They record five distinct, but related intervals characterized by 1) Upper Cambrian arkoses resting unconformably on Precambrian granite; 2) Lower Ordovician reworked subarkoses, sublitharentites, and quartzites; 3) Lower Ordovician to Lower Mississippian reworked orthoquartzites; 4) Upper Mississippian first cycle sandstones with few metamorphic rock fragments (mrfs); 5) Lower Pennsylvanian (Morrowan) first cycle sandstones with common mrfs and Middle Pennsylvanian (Atokan) first cycle sandstones with common to abundant mrfs. These sandstones accumulated on a gently sloping cratonic platform …

Plain Facts About Anthropogenic Global Climate Change And Warming: A Review, M. K. Cleaveland

Journal of the Arkansas Academy of Science

Anthropogenic global climate change (AGC) is proceeding rapidly. The proximate cause is the greenhouse effect of carbon dioxide, methane and other greenhouse gases (GHG), which have rapidly accumulated in the atmosphere from burning fossil fuels and other human activities. Measurements of incoming and outgoing radiation have verified the warming imbalance. Effects manifest themselves in accelerating sea level rise and diminishment of the cryosphere. This has already created climatic refugees and water stress, and will destroy coastal infrastructure. It also impacts ecosystems and biodiversity in many ways. To avoid catastrophic effects, fossil fuel use must cease and carbon sinks must be …

Impacts Of Man-Made Structures On Avian Community Metrics In 4 State Parks In Northwestern Arkansas, R. D. Keith, B. Grooms, R. E. Urbanek

Journal of the Arkansas Academy of Science

Avian community metrics often differ between areas with no human disturbance and areas with high levels of human disturbance. However, the relationships between avian community metrics and smaller-scale disturbances are not as clear. Our goal was to investigate if avian abundance, richness, evenness, and diversity differed in areas with and without small-scale human developments. We used fixed-radius 50-m avian point counts to compare points which contained a man-made structure (n = 47), such as a picnic area, road, or campsite to those that did not contain a man-made structure (n = 181) at 4 state parks in Arkansas during 18 …

Sedimentation In The Upper Reaches Of Lake Ouachita, J. A. Patton

Journal of the Arkansas Academy of Science

Lake Ouachita in west-central Arkansas is the largest man-made reservoir in the state. The lake was created by the U.S. Army Corps of Engineers (USACE) in 1953 for the purposes of hydropower, flood control, and recreation. Although Lake Ouachita is widely known for its high water clarity near Blakely Dam, little is known about the volume and ultimate fate of sediments that enter the lake from two primary tributaries: the North and South Forks of the Ouachita River. This project utilized a dual-frequency echo sounding system in combination with geographic information system and statistical analysis to calculate an average post-impoundment …

A General Valence-Length Correlation For Determining Bond Orders: Application To Carbon-Carbon And Carbon-Hydrogen Chemical Bonds, F. D. Hardcastle

Journal of the Arkansas Academy of Science

A quantum-mechanical LCAO approach was used to derive Pauling’s popular empirical bond valencelength relationship s = exp((R₀-R)/b), where s is the bond order or bond valence associated with bond length R, and R₀ and b are fitting parameters. An expression for the b “empirical” fitting parameter is derived in terms of atomic orbital exponents. The b parameters calculated from the atomic orbital exponents are consistent with optimized b parameters. In general, atomic orbital exponents may be used to determine bond valence-length relationships for any chemical bond regardless of valence state, oxidation number, physical or chemical environment. In this study, almost …

Sequence Stratigraphy Of The St. Joe And Boone Formations, Lower Mississippian (Kinderhookian-Osagean), Southern Ozark Region, S. C. Kincade

Journal of the Arkansas Academy of Science

The Lower Mississippian (Kinderhookian-Osagean) St. Joe and succeeding Boone Formations are well exposed in northwestern Arkansas, southern Missouri, and northeastern Oklahoma, forming the Springfield Plateau of the southern Ozark region. This interval represents a single, third order, transgressive-regressive eustatic cycle deposited broadly across the North American craton. The initial transgression during the Kinderhookian covered the regional erosional surface developed on either the Devonian-Lower Mississippian Chattanooga Shale, or older units with crinoidal packstones deposited as platform successions or transported as down-ramp slurries. The Boone Formation is divided informally into lower and upper divisions that reflect differences in eustatic sea level. The …

Geochemical Processes And Controls Affecting Water Quality Of The Karst Area Of Big Creek Near Mt. Judea, Arkansas, V. Brahana, J. Nix, C. Kuyper, T. Turk, F. Usrey, S. Hodges, C. Bitting, K. Ficco, E. Pollock, R. Quick, B. Thompson, J. Murdoch

Journal of the Arkansas Academy of Science

Karst regions typically are considered to be vulnerable with respect to various land-use activities, owing to the intimate association of surface and groundwater and lack of contaminant attenuation provided by most karst aquifers. Inasmuch as the soluble rocks of the karst landscape can be dissolved to create large, rapid-flow zones that compete successfully with surface streams, groundwater and subsurface flow represent a much larger component of the hydrologic budget in karst regions than in areas where non-soluble rocks predominate. Karst areas typically are distinguished by being unique, but some general approaches can be applied to characterize the hydrology of the …

Characterizing Nanoparticle Size By Dynamic Light Scattering, M. Zaman, S. Ang, S. Singh

Journal of the Arkansas Academy of Science

The Dynamic Light Scattering (DLS) Technique was used to determine the size, shape and diffusion coefficient of rod-like nanoparticles. The intensity auto-correlation functions of light scattered by particles in a solution were measured and analyzed to obtain the relaxation rates for decay of intensity correlations. These decay rates are related to the diffusion coefficients pertaining to the motion of the particle. In the case of nanorods, there are two types of motion - translational and rotational. By disentangling the relaxation rates, corresponding to these two types of motion, the shape and size of nanoparticles were characterized. These experiments, though limited …

Age And Correlation Of The Moorefield Shale (Upper Mississippian) In Its Type Area, Northeastern Arkansas, O. Dalu, W. S. Coffey, W. L. Manger

Journal of the Arkansas Academy of Science

The name Moorefield was proposed by Adams and Ulrich (1904) for exposures of gray to brown, phosphatic shale with a basal limestone, overlying the Lower Mississippian Boone Formation, and underlying the Upper Mississippian Batesville Sandstone, in the vicinity of Moorefield, Independence County, northeastern Arkansas. Gordon (1944) 1) restricted the name Moorefield to the lower limestone-bearing interval, 2) applied a new name, Ruddell, to the succeeding shale section that comprises the bulk of the interval, with a type area near Moorefield, and 3) interpreted the interval contacts as unconformities. The name Ruddell was used for the revised Geological Map of Arkansas …

Biomass (Yard Waste) Suspensions As Alternative Daily Cover Material For Landfills, R. Sharma, K. Arnoult, K. Hart, G. Phillips, S. Knight, M. Grappe

Journal of the Arkansas Academy of Science

Biomass makes up approximately 16% of the landfills (this number can vary significantly depending upon the geographical location and time of the year). A majority of the biomass disposed in landfills is comprised of yard waste including grass and leaf clippings. This is becoming a problem as most landfills are running out of space and it is expensive to build new landfills. Twenty-four states have prohibited the disposal of yard waste in landfills with more states likely to follow suit. To conserve landfill space it is important to identify processes and methods for effective utilization and disposal of yard waste. …

Lithostratigraphic Succession And Depositional Dynamics Of The Lower Mississippian, Southern Ozarks, Northern Arkansas And Adjacent Areas, F. Mcfarlin

Journal of the Arkansas Academy of Science

The Lower Mississippian interval comprises a single, third-order, eustatic cycle subdivided lithostratigraphically into the St. Joe Limestone (Hopkins 1893) and overlying Boone Formation (Branner 1891, Simonds 1891) with type areas in northern Arkansas. Coeval, homotaxial limestones occur in adjacent southwestern Missouri and northeastern Oklahoma, but neither Arkansas name is applied. To eliminate this “state line fault,” Missouri formation names for the St. Joe interval are recognized in Arkansas as members (ascending order): Bachelor, Compton, Northview, Pierson. The Boone interval in Missouri is represented by the (ascending order): Reeds Spring, Elsey, Burlington-Keokuk undifferentiated, but utilization of those names in Arkansas is …

Posting Topics ≠ Reading Topics: On Discovering Posting And Reading Topics In Social Media, Wei Gong, Ee-Peng Lim, Feida Zhu

Research Collection School Of Computing and Information Systems

Social media users make decisions about what content to post and read. As posted content is often visible to others, users are likely to impose self-censorship when deciding what content to post. On the other hand, such a concern may not apply to reading social media content. As a result, the topics of content that a user posted and read can be different and this has major implications to the applications that require personalization. To better determine and profile social media users’ topic interests, we conduct a user survey in Twitter. In this survey, participants chose the topics they like …