Physical Sciences and Mathematics Commons^™

Phosphorus And Nitrogen-Containing Soybean Oil Polyols: Effect On The Mechanical Properties And Flame Retardancy Of Polyurethane Foam, Deni̇z Öztaşkin, Lütfullah Yusuf Yi̇vli̇k, İlayda Acaroğlu Degitz, Tarik Eren

Turkish Journal of Chemistry

In recent years, there has been an increasing interest in producing new materials that use renewable resources and halogen-free flame retardants with nonleaching properties. This research focuses on designing and synthesizing phosphorus-nitrogen-based biopolyols for use in polyurethane (PU) foam production. Polyol (ESBO-DYM) with dual functionalities, renewability, and nonflammability is synthesized through the epoxy ring-opening reaction of epoxidized soybean oil with phosphorus and nitrogen-containing tetraol products (DYM). The mechanical and flame retardant properties of PU foams with the addition of an ESBO-DYM were investigated. Increasing the amount of phosphorus in the PU foams increased the thermal stability properties. Using 100% ESBO-DYM …

Exploring Cation Exchange: Unveiling Its Significance In Biochar And Bioenergetics Applications, Gyanendra Kharel

Chemistry & Biochemistry Theses & Dissertations

Cation exchange, a cornerstone of soil chemistry and nutrient cycling, is a fundamental chemical process that occurs in soils, sediments, membranes, and other solid materials. It involves the interchange of positively charged ions, or cations, between a solid matrix and a surrounding solution. This process is crucial in various natural and engineered systems, leading to a range of applications across different fields.

This dissertation presents an extensive investigation into the applications of cation exchange in the fields of biochar and bioenergetics, encompassing three distinct aims. The first aim concentrates on the surface oxygenation of biochar through ozonization, aiming to achieve …

Phosphorus And Its Role In Chemical Evolution, Asbel Gonzalez

PANDION: The Osprey Journal of Research and Ideas

Phosphorus is a minor element with a cosmic abundance of about 105.5 atoms per 1012 H atoms (Boudreaux, n.d.). Phosphorus was depleted as a volatile throughout the developing solar system, and as a result, volatile forms of phosphorus would have been minimal, even in the colder regions of the solar nebula. Despite its low abundance, phosphorus minerals play key roles in planetary petrology, including through the formation of phosphate minerals that trapped volatiles and rare Earth elements, and in the formation of metal phosphides that may have served as nucleation sites for kamacite and taenite crystal growth in minor planet …

Synthesis, Characterization, And Thermal Investigation Of Metal Phosphites And Potential Implications For Astrobiology, Kimberly Faye Meyberg

Master of Science in Chemical Sciences Theses

The role of phosphorus in biochemistry is well understood. However, the route by which phosphorus was incorporated into early biomolecules on the prebiotic Earth is uncertain. Phosphate, the most prevalent species of phosphorus found in Earth’s geological record, is insoluble and unreactive with organics in aqueous environments. While the most abundant biogenic elements (C, N, H, O, and S) can be found in a volatile phase under terrestrial conditions, phosphorus cannot, suggesting that minerals must have been the main sources of phosphorus on the early Earth. One possible explanation is that phosphite was a major source of reduced, reactive phosphorus …

Harmful Algal Blooms In Caesar Creek Lake And Their Relationship To Riparian Cover, Morgan C. Grunden

Browse all Theses and Dissertations

Caesar Creek Lake (CCL) in Warren County, OH has recently been experiencing harmful algal blooms (HABs) which are most likely attributed to an excess of phosphorus (P) from fertilizers and manures applied to surrounding fields. Sediments act as a sink for P later supplying a source of P in lakes for HABs when waters become thermally stratified and anoxic. This study seeks to determine the relationship between HABs in CCL and riparian cover at the main tributaries, Anderson Fork and Caesar Creek. In order to do this, sediment samples were collected from four sample sites along Anderson Fork and three …

Influence Of Dissolved Organic Matter On Phosphate Interactions With Hydrous Ferric Oxides, Alaa Hasan Alsherbi

Theses and Dissertations (Comprehensive)

Phosphorus, iron oxides, and dissolved organic matter (DOM) are components present in all aquatic systems. Excess amounts of phosphorus in aquatic systems have the potential for toxic effects, in particular, contributing to eutrophication. Most of the previous studies performed looked at the surface complexation of inorganic phosphate anions (P) to mineral surfaces such as hydrous ferric oxide (HFO). However, the role of DOM on the interactions between HFO and P is unknown. This study investigates the influence of DOM on the surface complexation of P onto HFO surfaces. Moreover, this study looks at the possibility of cation bridging formation (Ca …

Corn And Soybean Response To Wastewater-Recycled Phosphorus Fertilizers, Shane Ylagan

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

The ability to recycle phosphorus (P) from wastewaters could provide a sustainable, continuous source of P that might also help protect surface water quality from P enrichment. The mineral struvite (MgNH4PO4·6H2O) is an understudied material that can be created from Pcontaining wastewater and has been shown to have agricultural fertilizer value. The objective of this study was to evaluate the effects of electrochemically precipitated struvite (ECST), chemically precipitated struvite (Crystal Green; CG), diammonium phosphate (DAP), monoammonium phosphate (MAP), rock phosphate (RP), and triple super phosphate (TSP) on corn (Zea mays) and soybean (Glycine max) response in a 79-day greenhouse pot …

Phosphorus Variability In The Area Of Influence Of The Mid-Barataria Sediment Diversion, Peter Mates

LSU Master's Theses

Man-made levees along the lower Mississippi River prevent delivery of sediment from building and maintaining Louisiana’s coastal wetlands. The Mid-Barataria sediment diversions is designed to reintroduce Mississippi River water, sediment, and nutrients into the sediment-starved Barataria Basin. Phosphorus (P) is an important macronutrient for regulating primary production in coastal marine ecosystems. Wetlands can serve as a sink or source for phosphorus to the overlying water column through various retention and release processes, dependent on concentration. Louisiana coastal systems can be phosphorus limited due to much higher concentrations of bioavailable Nitrogen in river water. The high soluble molar N:P ( >50:1) …

Phosphorus Nmr And Its Application To Metabolomics, Paula Evans, Fatema Bhinderwala, Robert Powers, Martha Morton, Thomas Smith

UCARE Research Products

Stable isotopes are routinely employed by NMR metabolomics to highlight specific metabolic processes and to monitor pathway flux. 13C-carbon and 15N-nitrogen labeled nutrients are convenient sources of isotope tracers and are commonly added as supplements to a variety of biological systems ranging from cell cultures to animal models. Unlike 13C and 15N, 31P-phosphourous is a naturally abundant and NMR active isotope that doesn’t require an external supplemental source. To date, 31P NMR has seen limited usage in metabolomics because of a lack of reference spectra, difficulties in sample preparation, and an absence of two-dimensional (2D) NMR experiments. But, 31P NMR …

Zinc–Phosphorus Clusters For Solution Synthesis Of Zinc Phosphide Nanoparticles, Kyungseop Lee

Electronic Thesis and Dissertation Repository

Synthesis of zinc phosphide (Zn₃P₂) nanoparticles is an emerging topic of investigation as Zn₃P₂ is a candidate material for the next generation solar cells. Despite the early discovery of its favorable electronic properties that are well-suited for photovoltaic applications, a major focus of synthetic strategy was with vapor/chemical deposition methods. Solution methods with greater control over size, crystal structure and composition at a lower production cost, has been underdeveloped in comparison. In this context, this thesis describes the synthesis, characterization and reactivity of zinc phosphido clusters: [Zn₂(μ-PPh₂)₂(PPh …

Methodologies For Metal Functionalization Of Phosphorus Based Photopolymer Networks, Vanessa Béland

Electronic Thesis and Dissertation Repository

Photopolymer networks with phosphonium cation, alkyl phosphine and olefin functionality were designed, synthesized and functionalized with metals by metathesis, coordination and hydrometallation reactions, respectively. The materials were strategically designed so that the metal functionalization step could be monitored and quantified. In some cases, this involved characterization by IR, NMR, or X-ray spectroscopic techniques, or by comparison to molecular analogues. It was found that by using a bi-functional photopolymer network, the material could be bi-metallized by orthogonal mechanisms. All metallized polymer networks were tested for their suitability as precursors to metal-containing ceramics. The polymers were pyrolyzed, and on analysis it was …

Modeled Affinity Constants For Phosphorus Adsorption And Desorption Due To Saltwater Intrusion, Yasemin Taşcı

USF Tampa Graduate Theses and Dissertations

It is important to understand the processes that regulate phosphorus (P) fluxes to coastal environments, because P is an important nutrient in coastal ecosystems. Phosphorus adsorbs to the surface of minerals in sediment and bedrock, and an influx of seawater can cause some of that P to desorb, raising the P concentration of ambient water. Although seawater-induced P desorption is thought to be an important source of P to coastal environments, the chemical reactions that underlie it have not been established. Previous work provides some relevant surface reactions and associated affinity constants between various aqueous P species and the surface …

Controls On Phosphorus Export From An Agricultural Watershed: Amsden Brook, Fort Fairfield, Maine Usa., Gregory J. Mcdonald

Electronic Theses and Dissertations

This study explores the sources and mechanisms of phosphorus (P) mobilization during base flow within the Amsden Brook watershed, Fort Fairfield, Maine, USA. Amsden Brook is an agriculturally dominated watershed drained by a spring-fed and perennial first- to second-order stream. We characterized the P concentrations within the watershed to investigate connections between soils, stream sediment, surface water, and groundwater. Waters were monitored monthly during the 2017 snow-free period for temperature, pH, dissolved oxygen, conductivity, soluble reactive P (SRP), total P, strong acid anions, strong base cations, dissolved organic carbon (DOC), Al, Fe, and Mn. Phosphorus speciation within soils and sediment …

From The River To The Gulf: An Investigation Of Biogeochemical Cycling In Wetland Soils And Coastal Shelf Sediments, Katie Bowes

LSU Master's Theses

Louisiana is home to 40% of the coastal wetlands in the lower 48 states, yet accounts for 80% of the coastal wetland loss in this region. This loss is attributed to decreased sediment supply, levee alteration, sea level rise, channelization, and subsidence. The levee system in Louisiana disconnected coastal wetlands from the main stem of the Mississippi River (MSR), reducing the amount of land-building sediment that reaches coastal wetlands. This disconnection also allows a greater percentage of river discharge, including agricultural contaminants and runoff, to flow into the northern Gulf of Mexico (NGOM).

The 2012 Coastal Master Plan proposed eight …

Exploring The Chemistry Of Asymmetric Phosphines & Phosphinidene Sulfides, Taylor E. Pritchard

Electronic Thesis and Dissertation Repository

The field of low-coordinate main group chemistry has seen huge development in the last 30 years, with novel compounds that demonstrate unique structures and reactivity. Isolation of these species has relied on thoughtfully designed substituents normally containing substructure steric bulk. The area of phosphinidene chalcogenide isolation and transfer remains poorly understood by comparison. In this context, the major focus of thesis was on the development of a room-temperature method for the transfer of RP=S moieties with and without sterically demanding substituents. The preparation and complete characterization of new asymmetric phosphines with m-terphenyl ligands was also reported. In Chapter 2, …

Exploring The Synthesis, Structure, And Reactivity Of Phosphorus-Chalcogen Heterocycles, Cameron Graham

Electronic Thesis and Dissertation Repository

In recent years, the field of low-coordinate main group chemistry has seen significant research interest due to their unique structures and unprecedented reactivity. Conversely, the area of phosphinidene chalcogenides, a low-coordinate phosphorus and chalcogen species, have yet to be thoroughly explored. In this context, this dissertation describes the synthesis of a number of phosphorus-chalcogen heterocycles that can be degraded to provide stoichiometric access to low-coordinate phosphorus species. The ability for successful P-Ch transfer relies on using a bulky m-terphenyl group at phosphorus that provides enough steric bulk to kinetically stabilize the phosphorus centre, but also accommodating enough to allow …

Seasonal And Spatial Variations In Chemical Composition And Fluxes Of Dissolved Organic Matter And Nutrients In The Lower Milwaukee River, Tarek A. Teber

Theses and Dissertations

Physical, chemical and biological processes directly influence the transport, composition, and fluxes of dissolved organic matter (DOM) in river watersheds. Changes in the abundance and composition of DOM and nutrients (P&N) in the watershed should reflect changes in hydrological cycle, effluent discharge, land-use and land-cover, and anthropogenic activities in the river basin, especially in rivers that run through metropolitan areas such as the Milwaukee River. Despite the importance of DOM to ecosystem health and function, a literature search to date finds no comprehensive accounting of DOM in the Milwaukee River. To examine DOM dynamics, monthly water samples were collected between …

Exploring The Chemistry Of Phosphorus For Photopolymer Applications, Ryan Guterman

Electronic Thesis and Dissertation Repository

Prior to this thesis, phosphorus-containing polymers and photopolymerization represented two distinct, non-overlapping fields of study. This thesis examined the prospect of combining these two approaches to create a system possessing the benefits of both techniques. By exploiting the chemistry of phosphorus, and using photopolymerization as a fabrication method, new materials were developed and assessed for their use in various applications.

Among the many phosphorus compounds that may be used in polymer science, phosphonium salts and primary phosphines were of specific focus. First, highly fluorinated phosphonium monomers were developed to create photopolymerized hydrophobic surfaces. A structure-activity relationship was established, as both …

Evaluation Of The Feasibility Of Struvite Precipitation From Domestic Wastewater As An Alternative Phosphorus Fertilizer Resource, Amanda R. Bird

Master's Projects and Capstones

Finite phosphate rock ore reserves are estimated to be exhausted in 100 to 150 years. Phosphate rock ore is the single global source material for phosphorus fertilizer production. Once these reserves are gone, agricultural production will be negatively impacted. There are currently no alternative phosphorus resources. However, phosphorus concentrations present in human excrement traveling through domestic wastewater treatment facilities is being disposed of directly to the environment, often resulting in pollution problems. Recovering phosphorus from wastewater with struvite precipitation systems at wastewater treatment plants can alleviate future phosphorus scarcities. Evaluation of phosphorus recovery through struvite precipitation at wastewater treatment plants …

Analysis Of Nitrogen And Phosphorus Nutrients In Lake Sediment, Kelsey L. Berrier

Senior Honors Projects, 2010-2019

Analytical methods for the determination of nitrogen and phosphorus nutrients (NO₃-N, NH₄-N and PO₄-P) in sediment were studied with the goal of developing extraction steps compatible with analysis by ion chromatography (IC). Research focused on extractant solution composition, Dionex OnGuard^® sample pretreatment cartridges for salt removal, and chromatographic resolution. Aqueous test samples, lake sediment samples and spiked lake sediment samples were analyzed. Dionex Ag, Ag/H, and H cartridges were studied for the pretreatment step. Silver (Ag) cartridges were found effective in removing >99% of interfering chloride ion to allow NO₃-N determination …

Phosphorous Acid Route Synthesis Of Iron Tavorite Phases, Lifepo₄(Oh)ₓf₁₋ₓ [0 ≤ X ≤ 1] And Comparative Study Of Their Electrochemical Activities, Hooman Yaghoobnejad Asl, Amitava Choudhury

Chemistry Faculty Research & Creative Works

New synthesis routes were employed for the synthesis of three derivatives of iron hydroxo-, fluoro-, and mixed hydroxo-fluoro phosphates LiFePO ₄(OH)_xF_1-x where 0 ? x ? 1 with the tavorite structure type, and their detail electrochemical activities have been presented. The hydrothermal synthesis of the pure hydroxo-derivative, LiFePO₄OH, using phosphorous acid as a source of phosphate yielded good quality crystals from which the crystal structure was solved for the first time using SC-XRD (single crystal X-ray diffraction). The fluoro derivative, LiFePO₄F, was prepared as a very fine powder at low temperature in …

Exploring The Synthesis And Coordination Chemistry Of Zwitterionic Main Group Compounds, Jonathan W. Dube

Electronic Thesis and Dissertation Repository

Traditionally low coordinate and low oxidation state main group compounds are isolated utilizing hard anionic donors based on carbon and nitrogen based ligands. Conversely, employing anionic phosphines for this role has been essentially unexplored. In this context, this dissertation describes the synthesis of a number of main group complexes, ranging from group 13 to group 15, utilizing the bis(phosphino)borate ligand class in a supporting role. The remote anionic borate backbone renders the complexes zwitterionic and provides access to unique compounds that possess structures, and exhibit onwards reactivity, that is very different to the analogous compounds stabilized with neutral phosphines. For …

Uncovering New Bonding Motifs: The Synthesis Of Chalcogen And Phosphorus Complexes Supported By Nitrogen Based Ligands, Caleb D. Martin

Electronic Thesis and Dissertation Repository

The chemistry of the main group elements with nitrogen based ligands has been an area that has received little attention in comparison to transition metals. The preliminary investigations have focused on groups 13 and 14 revealing new bonding motifs and interesting reactivity. This has motivated us to synthesize group 15 and 16 derivatives in new bonding arrangements capable of activating small molecules.

In pursuit of isolating such species, the reactivity of sulfur dichloride and “S(OTf)2” with a series of diazabutadiene (DAB) ligands was explored. The substitution on the ligand was extremely influential on the outcome of the reaction. Alkyl groups …

Theoretical And Experimental Studies In Nuclear Magnetic Resonance, Adrienne M. Roehrich

Department of Chemistry: Dissertations, Theses, and Student Research

Nuclear magnetic resonance (NMR) is a tool used to probe the physical and chemical environments of specific atoms in molecules. This research explored small molecule analogues to biological materials to determine NMR parameters using ab initio computations, comparing the results with solid-state NMR measurements. Models, such as dimethyl phosphate (DMP) for oligonucleotides or CuCl for the active site of the protein azurin, represented computationally unwieldy macromolecules. ³¹P chemical shielding tensors were calculated for DMP as a function of torsion angles, as well as for the phosphate salts, ammonium dihydrogen phosphate (ADHP), diammonium hydrogen phosphate, and magnesium dihydrogen phosphate. The …

Aluminum And Phosphorus Separation: Application To Preparation Of Target From Brain Tissue For 26Al Determination By Accelerator Mass Spectrometry, Russell D. Brauer, J. David Robertson, Pankaj Sharma, Robert A. Yokel

Pharmaceutical Sciences Faculty Publications

Acid digested brain containing 4 mg added ²⁷Al was ashed at 1000°C to prepare an Al₂O₃ target for accelerator mass spectrometry (AMS) analysis of ²⁶Al. A glass-like material usually resulted which was thought to be aluminum (Al) oxyphosphate. The separation of Al and phosphate was investigated. Al, but not phosphate, was bound by a cation exchange resin (AG 50-X8). Hydrofluoric acid eluted the Al from the resin. Removal of phosphate from acid digested brain by this method produced an amorphous material after ashing that was easier to recover from the porcelain crucible and had a …

Interagency Lake Mead And Las Vegas Wash Monitoring Program: Standard Operating Procedures Manual, Bureau Of Reclamation, City Of Henderson Water Reclamation Facility, City Of Las Vegas Water Pollution Control Facility, Clark County Sanitation District, Nevada, Southern Nevada Water Authority

Publications (WR)

A number of agencies sample Lake Mead and the Las Vegas Wash on a routine basis at several locations. In order to share and properly interpret the data, the Bureau of Reclamation, Southern Nevada Water Authority and the three Wastewater Treatment Facilities (City of Las Vegas, Clark County Sanitation District and City of Henderson) formed a committee to examine sampling and analytical protocols and to share information with the goal of maximizing the data quality. The group first met in April 1997.

It was agreed that an effort should be made to discuss and compare specific sampling and analytical techniques …

Nutrient Limitation In A Southwestern Desert Reservoir: Eutrophication Of Las Vegas Bay, Lake Mead, Nevada, Davine M. Lieberman

Publications (WR)

Algal bioassay tests were conducted with Selenastrum capricornutum and natural algae on inner Las Vegas Bay, Lake Mead, Nevada, from December 1992 through September 1993, to identify any nutrient limitation in an area of the reservoir that has experienced problems associated with severe nutrient enrichment. Three areas were sampled based on a gradient of water quality conditions that existed in Las Vegas Bay (LVB). Disodium ethylenedinitrilotetraacetate (EDTA) significantly stimulated algal growth compared to non-EDTA treatment. Algal bioassays indicated that phosphorus (P) was the primary limiting nutrient at all stations for most of the test dates. Chl a response with EDTA …

Intensive Animal Industries In The Peel-Harvey Catchment, R W. Payne

Journal of the Department of Agriculture, Western Australia, Series 4

The Swan coastal plain to the north and south of Perth is attractive for the intensive production of pigs and poultry for several reasons. It is close to markets, feed manufacturers and labour; has a less extreme climate than inland areas; and is underlain by a large reserve of high quality groundwater.

Because these are all intensive operations, large quantaties of nutrient-rich waste are produced over a very small area. They can severely damage ground and surface waters unless steps are taken to control the wastes which they produce.

This article oulines both the nature of intensive aniamal industries in …

Limnological Monitoring Data For Lake Mead During 1987: Technical Report No. 20, Larry J. Paulson

Publications (WR)

Limnological monitoring was conducted in Las Vegas Bay and Boulder Basin from April to December of 1987. The purpose of the monitoring was to (i) document possible changes in water quality resulting from decreased phosphorus loading in Las Vegas Wash, and (ii) establish a data base for evaluating the adequacy of water quality standards.

River Discharge Study, Laughlin, Nevada: Colorado River Model And Diffusion Study, B. Dennis Hugh, David L. Stringfield, Jill C. Bicknell, Robert A. Ryder, Clark County Sanitation District, Nevada

Publications (WR)

A water quality modeling study of the Mohave Reach of the Lower Colorado River (from Davis Dam to the Nevada/California Stateline) was conducted to evaluate potential water quality impacts resulting from a proposed Laughlin, Nevada wastewater effluent discharge. The study included four major components: (1) review of the current regulatory framework; (2) a field data collection program to document existing water quality conditions in winter, summer, and fall; (3) development and verification of far-field and near-field (mixing zone) water quality models; and (4) application of the models to project future river quality conditions for several treatment-discharge alternatives as well as …