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Molecular Insights Into The Redox Of Atmospheric Mercury Through Laser Spectroscopy, Rongrong Wu Cohen

Theses and Dissertations

The widespread pollution of mercury motivates research into its atmospheric chemistry and transport. Gaseous elemental mercury (Hg(0)) dominates mercury emission to the atmosphere, but the rate of its oxidation to mercury compound (Hg(II)) plays a significant role in controlling where and when mercury deposits to ecosystems. Atomic bromine is regarded as the main oxidant for Hg(0) oxidation, known to initiate the oxidation via a two-step process in the atmosphere – formation of BrHg (R1) and subsequent reactions of BrHg with abundant free radicals Y, i.e., NO2, HOO, etc. (R2), where the reaction of BrHg +Y could also lead to the …

Development And Characterization Of A Peanut-Shell Based Activated Carbon And The Outcomes Of A Hands-On Approach To Chemical Education, Danielle Pitre

Theses and Dissertations

Heavy metals are a recognized toxic environmental contaminant, even at very low concentrations. There have been well-known events in the last decade within the US of high amounts of lead in the drinking water supplies of cities, leading to detrimental effects within its population. Ways have been found to remove this metal, and others, from water with expensive adsorbents. The aim of the first part of this research was to create an inexpensive adsorbent from a waste material and modify it in such a way that it would be adept at removing heavy metals from water.

In Chapter I, we …

Phosphorus Enriched Modified-Douglas Fir Biochar As A Soil Amendment, Beatrice Arwenyo

Theses and Dissertations

Biochar application as a soil additive is gaining global acceptance. In this era of climate change, biochar use for improved soil productivity is not just a sustainable eco-friendly substitute to synthetic fertilizer, but a noble contributor to the fight against climate change. Although biochar has been accredited with some environmental and agricultural benefits, most studies concentrated on agricultural and biowaste products as feedstocks. This research was designed to explore P-enriched modified-Douglas fir biochar potential as a soil additive. Using corn as a test crop, greenhouse studies were performed on acidic sandy soil, comparing phosphorus enriched modified-Douglas fir biochar efficacy to …

Functionalized Biochar Electrodes For Asymmetric Capacitive Deionization, Hellen Stephanie

Theses and Dissertations

Electrosorption-based capacitive deionization (CDI) has become a viable process for brackish water desalination and defluoridation. In this study, activated Douglas fir biochar is used as a low-cost electrode material with adsorption capacity comparable to activated carbon obtained from biomass precursors. Adding functional groups to the activated biochar enhanced salt removal capacity, providing cation and anion selectivity. The functionalized electrodes were prepared by Nafion, titanium isopropoxide, and p-phenylenediamine treatment, respectively, which introduced sulfonate, titanium dioxide and amine functional groups to the electrode surface. These modification methods are versatile and can be easily performed without sophisticated laboratory environment. Modified biochar electrodes …

In Vitro And In Vivo Identification And Quantification Of Carmofur And 5-Fluorouracil Using Tandem Mass Spectrometry, Mohammad Mohiminul Islam

Theses and Dissertations

Glioblastoma is the most aggressive solid tumor of the brain. Prior studies from our lab found that carmofur, also known as 1-hexylcarbanoyl 5-fluorouracil (HCFU) is a promising candidate in suppressing and killing tumor cell lines compared to the FDA-approved drug temozolomide. Originally developed as pro-drug of 5-fluorouracil (5-FU), carmofur has been in use in clinic for the treatment of colorectal cancer for over four decades in Japan. Having it used in clinics, it has a high probability of repurposing for diseases with no cure such as glioblastoma. Carmofur has also been found effective against other cancers such as head and …

Physicochemical Properties, Pharmacokinetics And Biodistribution Of Arm14988, An Acid Ceramidase Inhibitor, And Its Potential As Chemotherapeutic Agent For Glioblastoma, Vilashini Rajaratnam

Theses and Dissertations

Glioblastoma (GBM) is one of the most common and detrimental forms of brain tumor. While there are few FDA-approved chemotherapeutic treatments, the overall survival is still poor leading to many studies dedicated to developing more effective treatment options. Previous studies have identified acid ceramidase (ASAH1) as a potential therapeutic target for this disease. ARN14988, an ASAH1 inhibitor, has shown to be highly cytotoxic compared to the FDA-approved chemotherapy agent, temozolomide, in GBM cell lines. This initial finding makes ARN14988 a desired candidate for further drug discovery studies. Herein, the objective of this thesis is to study the pharmacological properties of …

Behavioral Screening And Chiral Bioanalysis Of Emerging Stimulant-Type Drugs In Rats, Tyson R. Baird

Theses and Dissertations

The epidemic of drug use in the United States and elsewhere in the world has resulted in tragic loss of life and substantial economic costs. Novel psychoactive substances (NPS) are one of the contributors to this problem, and the lack of information about many of these drugs compounds their risk. This dissertation proposes a strategy to use intracranial self-stimulation (ICSS) as a behavioral screening tool to assess emerging drugs of abuse for their abuse potential in order to generate a proactive threat assessment. A series of stimulant-type drugs including methcathinone, α-pyrrolidinohexanophenone (α-PHP), cocaine, and the phenyltropane analogs of cocaine WIN35428 …

Analysis Of Microdroplets And Microorganisms By Single Entity Electrochemistry, Junaid U. Ahmed

Theses and Dissertations

Single Entity Electrochemistry (SEE) is an emerging electrochemical technique that has been used to characterize discrete entities by measuring the change in current or potential during individual stochastic events (collision or adsorption) of an entity with an ultramicroelectrode (UME) of similar dimensions. The shape and magnitude of the SEE signal depend on the underlying mechanism of interaction with the UME surface. There is a critical need for quantitative models that correlate the SEE signal with properties of the entity-UME system, including effects of acquisition instrumentation, to prevent misinterpretation of data.

This research focused on integrated experiments and simulations to quantify …