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Full-Text Articles in Physical Sciences and Mathematics

Distribution And Soil Characteristics Associated With The Neches River Rose-Mallow (Hibiscus Dasycalyx), Morgan E. Langlinais Dec 2022

Distribution And Soil Characteristics Associated With The Neches River Rose-Mallow (Hibiscus Dasycalyx), Morgan E. Langlinais

Electronic Theses and Dissertations

The Neches River rose-mallow, Hibiscus dasycalyx, is a rare herbaceous perennial endemic to East Texas. The threatened, obligate wetland species is currently at risk of being lost in the wild due to habitat loss, encroachment of nonnative and native plant species, and hybridization with two other Hibiscus congeners, Hibiscus laevis and Hibiscus moscheutos. Known locations of each of the three Hibiscus species were used to measure select soil characteristics and habitat variables associated with each of the rose-mallows. H. dasycalyx was concluded to be associated with more fertile soils and slightly more canopy coverage than H. laevis and …


Differentiate Metasploit Framework Attacks From Others, Gina Liu Ajero Dec 2022

Differentiate Metasploit Framework Attacks From Others, Gina Liu Ajero

Electronic Theses and Dissertations

Metasploit Framework is a very popular collection of penetration testing tools. From auxiliaries such as network scanners and mappers to exploits and payloads, Metasploit Framework offers a plethera of apparatuses to implement all the stages of a penetration test. There are two versions: both a free open-source community version and a commercial professional version called Metasploit Pro. The free version, Metasploit Framework, is heavily used by cyber crimininals to carry out illegal activities to gain unauthorized access to targets.

In this paper, I conduct experiments in a virtual environment to discover whether attacks originated from Metasploit Framework are marked with …


Turning Ligands On Their Side: Computational Investigation Into The Binding Of N2o And N2 In Transition Metal Complexes, Cole Donald Dec 2022

Turning Ligands On Their Side: Computational Investigation Into The Binding Of N2o And N2 In Transition Metal Complexes, Cole Donald

Electronic Theses and Dissertations

Common greenhouse gas nitrous oxide (N2O) is a thermodynamically potent and environmentally benign oxidant, making it a desirable target for metal center activation. Unfortunately, N2O is a poor ligand for transition metals due to its weak sigma-donating and pi-accepting properties; as a result, few transition metal complexes capable of interacting with N2O have been found. As the primary source of all nitrogen in organisms, abundant gas dinitrogen (N2) is a crucially important tiny molecule and an essential part of daily existence. However, due to its inertness, it has limited practical uses in …


Soil Salinity And Sodicity Of Galveston And Pelican Islands, Texas, Rachel Murray Aug 2022

Soil Salinity And Sodicity Of Galveston And Pelican Islands, Texas, Rachel Murray

Electronic Theses and Dissertations

Galveston Island, Texas, is frequently affected by hurricanes. In 2008, Hurricane Ike inundated much of the island with seawater, causing elevated soil salinity levels that killed much of the vegetation on the island, including tens of thousands of trees. Residual salinity in soils and groundwater has hampered vegetation re-establishment in some areas.

This project aims to create a map product that displays the current soil salinity and sodicity levels on Galveston and Pelican Islands. The existing USDA Natural Resource Conservation Service (NRCS) Galveston County Soil Survey map units were used as a base for the project. ArcGIS Desktop software was …


Geochemical Characterization Of The Louann Salt, Puma Field, Green Canyon, Gulf Of Mexico Basin – Using Xrf And Xrd, Brian Lesh Aug 2022

Geochemical Characterization Of The Louann Salt, Puma Field, Green Canyon, Gulf Of Mexico Basin – Using Xrf And Xrd, Brian Lesh

Electronic Theses and Dissertations

The Jurassic-aged Louann Salt is an evaporite sequence deposited in the Gulf of Mexico Basin (GOMB). It is an important component of the GOMB petroleum system and influences the facies pattern in overlying strata and the distribution of petroleum stratigraphic traps. The Louann Salt is composed primarily of halite with intercalated anhydrites and silty or sandy-halite intervals, with overall thicknesses in excess of four kilometers (~13,000 feet). Suture zones occur intermittently within the Louann Salt, formed by the collision of allochthonous evaporite layers. The mineralogy and geochemistry of the suture zones are currently understudied and can be hazardous during drilling …


Geochemical Characterization Of The Bone Spring Formation, Delaware Basin, Using Chemostratigraphy And Integrated Petrophysics, David Tonner Aug 2022

Geochemical Characterization Of The Bone Spring Formation, Delaware Basin, Using Chemostratigraphy And Integrated Petrophysics, David Tonner

Electronic Theses and Dissertations

The Delaware Basin forms part of West Texas's and New Mexico’s famous petroleum-generating Permian Basin. The Bone Spring Formation is a prolific hydrocarbon producer within this basin, creating one of the world’s richest oil shales. This formation has lithological sequences that are characterized by repeating carbonate and siliciclastic intervals of a third-order cycle which can largely be correlated to highstand and lowstand systems tracts, respectively. Lithological complexity and facies change are manifested by debris flows, turbidites, and slumps. In addition to glacio-eustasy, both tectonism and broader Milankovitch cycles have influenced the depositional history. Previous investigations have utilized cores and wireline …


Effects Of Excessive Soil Phosphorus Accumulation On Loblolly Pine (Pinus Taeda L.) Seedlings, Hannah C. Bays Aug 2022

Effects Of Excessive Soil Phosphorus Accumulation On Loblolly Pine (Pinus Taeda L.) Seedlings, Hannah C. Bays

Electronic Theses and Dissertations

Many landowners in East Texas apply poultry litter to pastures as a source of nitrogen (N) for forage crops. After many years of repeated poultry litter application, soils can accumulate extremely high extractable phosphorus (P) concentrations, sometimes over 1000 mg kg-1 of plant available P. Landowners report the conversion of these pastures to loblolly pine (Pinus taeda L.) plantations is often problematic, with poor seedling survival and abnormal tree growth. This study was conducted to assess the effects of excessive soil phosphorus on loblolly pine seedlings. An outdoor pot study was conducted using bare root seedlings and triple …


C-H On The Oxo Ferryl Wheel: Comparison Of Pyridine And Imidazole-Substituted Ligands For C-H Activation And Functionalization, Elizabeth Milem May 2022

C-H On The Oxo Ferryl Wheel: Comparison Of Pyridine And Imidazole-Substituted Ligands For C-H Activation And Functionalization, Elizabeth Milem

Electronic Theses and Dissertations

The selective and efficient transformation of hydrocarbon feedstocks is of high value for industry and research. While Shilov-type organometallic methods have facilitated this goal, systems designed after nature’s use of cheap and abundant iron-based enzymes are desired for wider-scale applications. This work establishes hydrocarbon oxidation efficiency of synthetic pyridine-based ligands (BPMEN, BPMPN) compared to commercially available TPA with in situ generated catalysts. Literature studies of traditionally synthesized BPMEN systems and initial in situ studies offered evidence for enhanced reactivity (TON) as compared to TPA. Expansion to a propyl backbone to produce BPMPN tested the increased chelate ring size’s impact on …


An Application Of Differential Mathematical Modeling Techniques To Study The Ongoing Rabies Epizootic In China, Christopher Turner May 2022

An Application Of Differential Mathematical Modeling Techniques To Study The Ongoing Rabies Epizootic In China, Christopher Turner

Electronic Theses and Dissertations

Rabies remains a global public health issue with a wide variety of neurological symptoms such as confusion, slight paralysis, hypersalivation, and hydrophobia. Rabies is usually fatal once symptoms appear. Many species are reservoirs for rabies, such as foxes, racoons, and wild dogs, which in turn can transmit the disease to humans, leading to complex transmission chains. There is a long latent period of rabies, between 1 to 3 months after infection, which further complicates control efforts. Mathematical modeling is a valuable tool in the study of infectious disease outbreaks and there have been many models applied to rabies outbreaks. However, …


Investigaion Of The Gamma Hurdle Model For A Single Population Mean, Alissa Jacobs Jan 2022

Investigaion Of The Gamma Hurdle Model For A Single Population Mean, Alissa Jacobs

Electronic Theses and Dissertations

A common issue in some statistical inference problems is dealing with a high frequency of zeroes in a sample of data. For many distributions such as the gamma, optimal inference procedures do not allow for zeroes to be present. In practice, however, it is natural to observe real data sets where nonnegative distributions would make sense to model but naturally zeroes will occur. One example of this is in the analysis of cost in insurance claim studies. One common approach to deal with the presence of zeroes is using a hurdle model. Most literary work on hurdle models will focus …