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Effect Of Biochar And Activated Carbon Amendments On Gaseous Mercury Emissions Of Soil And Mercury Methylation Rates In Sediment, Ryan Sessums

Honors Theses

Mercury is a pervasive global contaminant with a complex biogeochemical cycle. In this biogeochemical cycle, methylmercury (MeHg+) tends to biomagnify and concentrate in fish and seafood consumed by humans. This study examines the effect of sorbent amendments on both the mercury emission from soils and the methylation rates of mercury in sediments, both of which are believed to be major contributors to the global cycle. Biochar and activated carbon were used to treat soils and sediments to explore their effects. It was found that biochar and activated carbon reduced gaseous mercury emission by 25% and 49%, respectively. Methylation rates in …

The Effect Of Polyamines On I-Motif Thermal Stablity, Shelby Claire Liddell

Honors Theses

Polyamines are present inside cells at varying concentrations anywhere between 10 mM and 60 mM, and because of their molecular structure they contribute a positive charge to the interior of the cell. There has been previous evidence that the concentrations of polyamines have an effect on the stability of the DNA strands, which can affect the cellular processes. The particular DNA conformation studied is the i-motif, which is formed by intermolecular folding in cytosine rich strands. The i-motif studied is C20T, which is found in the promoter region of the oncogene, c-myc. Stabilization of c-myc can have an effect on …

Breastfeeding: Physiological And Cultural Influences, Alison R. Cegielski

Honors Theses

Within a biological perspective, breasts are indisputably for the use of nourishment of the young. This can be seen by how mammary glands are used by every other species other than humans. Humans are the only species that also looks at breasts within a cultural perspective, and that perspective is where the debate of breastfeeding occurs. There is really no debate that if given the option to breastfeed, breastfeeding is the best choice for the development of infants due to the fact that breast milk has been adapted for the human physique. In spite of the health benefits associated with …

Using Technology To Engage Students In The Stem Field, April Elizabeth Steen

Honors Theses

The United States is currently facing a shortage of qualified STEM professionals in the workforce and in research fields. Part of this lack of professionals can be traced back to lack of interest and lack of proficiency in mathematics and science at the secondary level of education as well as STEM major attrition at the college level. In an effort to increase student interest in STEM fields and increase retention of STEM majors, technology was employed to engage student interest. At the high school level, a physical chemistry demonstration on the spectroscopy of light was created. The demonstration was presented …

Ultrafast Hole Trapping And Relaxation Dynamics In P-Type Cus Nanodisks, John Ludwig, Li An, Brian Pattengale, Qingyu Kong, Xiaoyi Zhang, Pinxian Xi, Jier Huang

Chemistry Faculty Research and Publications

CuS nanocrystals are potential materials for developing low-cost solar energy conversion devices. Understanding the underlying dynamics of photoinduced carriers in CuS nanocrystals is essential to improve their performance in these devices. In this work, we investigated the photoinduced hole dynamics in CuS nanodisks (NDs) using the combination of transient optical (OTA) and X-ray (XTA) absorption spectroscopy. OTA results show that the broad transient absorption in the visible region is attributed to the photoinduced hot and trapped holes. The hole trapping process occurs on a subpicosecond time scale, followed by carrier recombination (~100 ps). The nature of the hole trapping sites, …

Potential Switchable Circularly Polarized Luminescence From Chiral Cyclometalated Platinum(Ii) Complexes, Xiao-Peng Zhang Zhang, Victoria Chang, Jian Liu, Xiao-Liang Yang, Wei Huan, Yizhi Li, Cheng-Hui Li, Gilles Muller, Xiao-Zeng You

Faculty Publications, Chemistry

A series of chiral cyclometalated platinum(II) complexes, [Pt((−)-L1)(Dmpi)]Cl ((−)-1), [Pt((+)-L1)(Dmpi)]Cl ((+)-1), [Pt((−)-L2)(Dmpi)]Cl ((−)-2), [Pt((+)-L2)(Dmpi)]Cl ((+)-2), [Pt3((−)-L2)2(Dmpi)4](ClO4)4 ((−)-3), and [Pt3((+)-L2)2(Dmpi)4](ClO4)4 ((+)-3) [(−)-L1 = (−)-4,5-pinene-6′-phenyl-2,2′-bipyridine, (+)-L1 = (+)-4,5-pinene-6′-phenyl-2,2′-bipyridine), (−)-L2 = (−)-1,3-bis(2-(4,5-pinene)pyridyl)benzene, (+)-L2 = (+)-1,3-bis(2-(4,5-pinene)pyridyl)benzene, Dmpi = 2,6-dimethylphenyl isocyanide], have been designed and synthesized. In aqueous solutions, (−)-1 and (+)-1 aggregate into one-dimensional helical chain structures through Pt···Pt, π–π, and hydrophobic–hydrophobic interactions. (−)-3 and (+)-3 represent a novel helical structure with Pt–Pt bonds. The formation of helical structures results in enhanced and distinct chiroptical properties as evidenced by circular dichroism spectra. Circularly polarized luminescence (CPL) was observed from the aggregates of (−)-1 and …

Curcumin: A Folklore Remedy From Kitchen On The Way To Clinic As Cancer Drug, Debasish Bandyopadhyay

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

Numerous compounds are widely distributed in nature and many of these possess medicinal/biological/pharmacological activity. Curcumin, a polyphenol derived from the rhizomes (underground stems) of Curcuma longa Linn (a member of the ginger family, commonly known as turmeric) is a culinary spice and therapeutic used in India for thousands of years to induce color and flavor in food as well as to treat a wide array of diseases. The origin of turmeric as spice and folklore medicine is so old that it is lost in legend. Curcumin has many beneficial pharmacological effects which includes, but are not limited with, antimicrobial, anti-inflammatory, …

Teaching Green Chemistry Principles To Undergraduate Students, Mariya Rozov, Tyler K. Brescia, Lyanne Valdez, Rita K. Upmacis

Faculty Papers and Publications

The environment is affected by the actions of mankind in multitudinous ways, many of which are detrimental, giving rise to pollution and toxic waste, ultimately making our planet less inhabitable. While remediation and new regulations help to prevent pollution and toxic waste, there is also a need to change the behavior of future generations of consumers and producers of new products. Future chemists and innovators are charged with the responsibility of developing new chemical processes and products that not only meet the needs of our growing population (in terms of energy, clean water and food), but also protect human health …

Synthesis And Testing Of Photosensitizer-Folate Conjugates And Potential Photosensitizers For Photodynamic Therapy, Jeffrey A. Trautmann

Dissertations

Dissertation Proposal for Jeffrey Trautmann

Photodynamic Therapy (PDT) is a technique that destroys oncogenic (cancerous) cells. It has been used in several countries since the 1980’s. Molecules that contain chromophores can function as photosensitizers, and will absorb light at various wavelengths (that being dependent upon the extent of their conjugation). Certain functional groups, upon absorption of light, can be used to convert O2 to singlet oxygens which are destructive to the cellular environment. Once an in-vitro cell contains a high enough concentration of photosensitizer material and light is able to reach the photosensitizer material, PDT can be used effectively to …

Physicochemical And Structural Analysis Of Polymers As Putative Drugs, Meghan L. Thompson

Theses and Dissertations

Sulfated low molecular weight lignins (LMWLs) have shown good activity as anticoagulants by allosterically inhibiting thrombin, as well as promising agents for treating emphysema through inhibition of elastolysis, oxidation, and inflammation. Sulfated LMWLs are chemo-enzymatically synthesized from starting monomers caffeic, ferulic, and sinapic acid into sulfated dehydropolymers known as CDS, FDS, and SDS. To further the LMWLs’ development as drugs, their structural composition and physicochemical characteristics were defined in this work. The molecular weight distribution profile of the sulfated LMWLs from size exclusion chromatography performed on a high pressure liquid chromatography system (SEC-HPLC) changed from bimodal when no surfactant is …

Synthesis Of Unnatural Amino Acids For Genetic Encoding By The Pyrrolysyl-Trna/Rna Synthetase System, William A. Knight

Theses and Dissertations

The complexity of all biomolecules in existence today can be attributed to the variation of the amino acid repertoire. In nature, 20 canonical amino acids are translated to form these biomolecules, however, many of these amino acids have revealed posttranslational modifications (i.e. acetylation, methylation) after incorporation. Amino acids that exhibit PTM are known for their involvement in cellular processes such as DNA repair and DNA replication; these PTMs are commonly found on histones within the chromatin complex. Utilization of in vivo site-specific incorporation has recently reported functionality of post-translationally modified amino acids.1 xii Here we report the synthesis and in …

A Continuous Process Towards The Synthesis Of Quinolones, Stevara N. Clinton

Theses and Dissertations

Abstract

The development of quinolones is described from the first quinolone to the latest fluoroquinolones. Quinolones have generated considerable interest since their discovery because of their antibacterial capabilities. Analogs incorporating the 4-quinolone ring system comprise a largely expanding group of synthetic compounds. The development of antibacterial resistance has created the need for an efficient synthesis of quinolones that can be easily adapted toward the assembly of quinolone based antibacterial drugs.

There are several reported approaches to the 4-quinolone ring system. Many of these methods use expensive starting materials, require the removal of high boiling solvents, or use high temperature conditions …

Colloidal Synthesis And Optical Characterizations Of Semiconductor Nanocrystals From Nontoxic Elements, Minh Q. Ho

Theses and Dissertations

To date, the search efforts have shifted from the toxic II-VI, III-V and IV-VI semiconductors to more environmentally friendly materials. Among Group II-V semiconductors, Zn₃P₂ has shown to be a more benign option, similar to Group IV (Ge, Si) materials, for future applications in photovoltaics and optoelectronics. This work is dedicated to the development of wet-chemical synthetic routes of (1) Zn₃P₂ and (2) Group IV (Ge, Si, Si_1-xGe_x) nanocrystals with precise control over composition, crystal structure, size and dispersity by adjusting different reaction parameters such as temperature, time and solvent …

Fabrication Of Tissue Precursors Induced By Shape-Changing Hydrogels, Olukemi O. Akintewe

USF Tampa Graduate Theses and Dissertations

Scaffold based tissue reconstruction inherently limits regenerative capacity due to inflammatory response and limited cell migration. In contrast, scaffold-free methods promise formation of functional tissues with both reduced adverse host reactions and enhanced integration. Cell-sheet engineering is a well-known bottom-up tissue engineering approach that allows the release of intact cell sheet from a temperature responsive polymer such as poly-N-isopropylacrylamide (pNIPAAm). pNIPAAm is an ideal template for culturing cell sheets because it undergoes a sharp volume-phase transition owing to the hydrophilic and hydrophobic interaction around its lower critical solution temperature (LCST) of 32°C, a temperature close to physiological temperature. Compared to …

2,4-Disubstituted Quinazolines With Antileishmanial Or Antibacterial Activity, Megan Marie Barber

USF Tampa Graduate Theses and Dissertations

Herein 47 2,4-disubstituted quinazolines were synthesized and tested against Leishmania donovani intracellular amastigotes. A structure-activity relationship was conducted and lead to the identification of quinazolines with EC50s in the single digit and high nanomolar range with favorable antileishmanial selectivity indexes. Quinazoline 2.6 and 2.31 underwent in vivo efficacy studies in murine models of visceral leishmaniasis, reducing liver parasitemia by 12 % and 24 %, respectively, when given by the intraperitoneal route at 15 mg/kg/day x 5 days. The antileishmanial efficacy and easy of synthesis make the 2,4-disubstituted quinazoline compound series a suitable platform for the future development of antileishmanial agents. …

Biosynthesis Of Long-Chain Fatty Acid Amides, Kristen A. Jeffries

USF Tampa Graduate Theses and Dissertations

The vast variety of long-chain fatty acid amides identified in biological systems is intriguing. The general structure of a fatty acid amide is R-CO-NH-X, where R is an alkyl group and X is derived from an immense variety of biogenic amines. Although structurally simple, the bioactivities of these molecules as signaling lipids are very diverse and have just recently begun to emerge in the literature. Interest in the long-chain fatty acid amides dramatically increased following the identification and characterization of one specific N-acylethanolamine, N-arachidonoylethanolamine (anandamide), as the endogenous ligand for the cannabinoid receptors in the mammalian brain. Since …

Development Of Orally Bioavailable 4(1H)-Quinolones And 1,2,3,4-Tetrahydroacridin-9(10H)-Ones With Potent Anti-Malarial Activity, Jordany Richarlson Maignan

USF Tampa Graduate Theses and Dissertations

Although Malaria rates are on the decline due to the efforts of the World Health Organization and other organizations dedicated to the eradication of this disease, a relaxed attitude towards the development of new antimalarial entities would be flawed. Due to the emergence of resistance in the parasite, the almost 50% world-wide reduction in malarial death rates that have been produced over the past 15 years are threatening to be lost

New drugs are urgently needed and our approach focuses on the re-evaluation and optimization of the historic antimalarial ICI 56,780. Due to its causal prophylactic activity, along with its …

Cappack Devices For Enhanced Qnmr Measurements In 1H Nmr Spectroscopy, Lingyu Chi

Masters Theses

"Quantitative NMR analyses can be improved by adding well-defined external references for measuring sample properties on absolute scales. Special Capillary-tube Package (CapPack) devices were invented that provide in situ information (e.g., temperature, pH, pressure, integration, chemical shift, lock, etc.) about a sample with spectral imprimaturs. A new microscale glass-sealing technique produced CapPack devices that can survive high temperatures and pressures in harsh environments. Two CapPack devices are discussed: (1) Gradient CapPack-- a device for examining the irradiation bandwidth of solvent-suppression pulse sequences; (2) T₁ CapPack - a device for examining the T₁ robustness of solvent-suppression pulse sequences. A …

Methods Of Analysis For Fermentation Science Products Using Various Analytical Techniques, Casey Jay Howdieshell

Online Theses and Dissertations

Fermentation science, the study of microorganisms as they digest food sources to produce usable products for consumption, has been around since the dawn of modern civilization. Historically, the fermentation process has been utilized for the production of alcoholic beverages. More recently, however, the production of bioethanol and biodiesel as a fuel source alternative to classical fossil fuels has gained increased popularity. As with any synthetic process, derivations and optimizations for ideal production are needed. As such, analytical techniques must be implemented to ensure quality control and pinnacle efficiency. This body of work describes analytical techniques providing key qualitative and quantitative …

Preparation And Characterization Of Self-Assembled Monolayers And Mesoscale Protein Patterning, Panae Noomuna

Online Theses and Dissertations

Bottom-up approach was used to develop self-assembled monolayers of octadecyltrichlorosilane (OTS) and undecenyltrichlorosilane(UTS) on Si(100) wafer. Undecenyltrichlorosilane monolayer was oxidized at the vinyl terminal to generate a carboxylic acid group. Lysozyme protein was immobilized on the polar carboxylic acid group. The developed protein patterns were investigated using fluorescence microscopy. Lysozyme has an isoelectronic point of 11.35. At a pH below this value the protein is positively charged making it a good candidate for electrostatic adsorption on the negatively charge -COO- group. Fluorescence images confirm formation of lysozyme across the silicon wafer. The patterned Si(100) wafer can be used as a …

A Water-Soluble Perylene Derivative For Live-Cell Imaging, Yongshan Ma, Fengxia Zhang, Jinfeng Zhang, Tianyi Jiang

Turkish Journal of Chemistry

Glutamic functionalized water-soluble perylene diimide, N, N'-di (L-glutamic amine)-perylene-3,4,9,10-tetracarboxylic diimide (GAPTCD) has three absorbance maxima at 469, 498, and 534 nm and two emission peaks at 550 and 587 nm. Owing to the highly negative electrostatic potential of the perylene plane, the perylene derivative showed good water solubility and strong fluorescence in alkali and neutral solutions. Both the absorbance and emission intensities decreased with the decreasing of pH from 9.66 to 5.92. This could be ascribed to the $\pi -\pi $ stacking produced by H$^{+}$ at the carboxyl group due to its electron accepting nature. Electrostatic potential maps also indicated …

Conversion Of Racemic Allylic Hydroperoxides Into Corresponding Chiral 1/2,3-Triols By Using Catalytic Oso$_{4}$ And Chiral Cinchona Ligands In The Absence Of Co-Oxidant, Haydar Göksu, Mehmet Serdar Gülteki̇n

Turkish Journal of Chemistry

For the first time, removal of oxygen atoms from allylic hydroperoxide functionality and reintroduction to the double bond was achieved using catalytic OsO$_{4}$ and chiral cinchona alkaloid derivatives in an acetone-water mixture to give corresponding chiral 1/2,3-triol with an enantioselectivity up to 99% ee. The hydroperoxide group was used as both a co-oxidant and a source of hydroxyl groups. This protocol is thought to have potential to provide opportunities for chiral synthesis of 1/2,3-triols from corresponding allylic hydroperoxides in the absence of co-oxidant in one stage for the first time in the literature.

A Case Study On In Vitro Investigations Of The Potent Biological Activities Of Wheat Germ And Black Cumin Seed Oil, Di̇dem Ağ Şeleci̇, Zi̇nar Pinar Gümüş, Murat Yavuz, Muharrem Şeleci̇, Rebecca Bongartz, Frank Stahl, Hakan Coşkunol, Suna Ti̇mur, Thomas Scheper

Turkish Journal of Chemistry

The objectives of this study were to investigate the potential biological activities of black cumin seed oil (BCSO) and wheat germ oil (WGO) on different cell lines. Initially, commercially available BCSO and WGO obtained by supercritical carbon dioxide extraction were analyzed in terms of tocopherol, aliphatic alcohols, and thymoquinone content via HPLC and GC analysis. Cell free antioxidant activities and total phenolic content of both oils were detected by DPPH assay and Folin-Ciocalteu method, respectively. As well as the DPPH assay, the protective effect against reactive oxygen species (ROS) was determined by microscopic observation of ROS generation in NIH-3T3 cells …

Three-Component Synthesis Of Cyclic $\Beta $-Aminoesters Using Ceo$_{2}$ Nanoparticles As An Efficient And Reusable Catalyst, Javad Safaei Ghomi, Sima Kalhor, Hossein Shahbazi-Alavi, Mehrnoosh Asgari-Kheirabadi

Turkish Journal of Chemistry

CeO$_{2}$ nanoparticles were used as an efficient catalyst for the preparation of cyclic $\beta $-aminoesters by three-component reaction between primary amines, ethyl acetoacetate, and chalcones in ethanol. Atom economy, low catalyst loading, reusable catalyst, and high yields of products are some of the important features of this protocol.

Reactivity Of The 2-Aryl-6,8-Dibromo-2,3-Dihydroquinolin-4(1$H)$-Ones In A Palladium Catalyzed Sonogashira Cross-Coupling Reaction, Malose Jack Mphahlele, Felix Adetunji Oyeyiola

Turkish Journal of Chemistry

Pd/C-PPh$_{3}$--CuI catalyzed Sonogashira cross-coupling of the 2-aryl-6,8-dibromo-2,3-dihydroquinolin-4(1$H)$-ones with phenyl acetylene or 3-butyn-1-ol afforded the corresponding 8-alkynylated quinolin-4(1$H)$-one derivatives, exclusively. Double carbo-substitution to afford the 6,8-dialkynyl derivatives was observed when PdCl$_{2}$(PPh$_{3})_{2}$ was used as Pd(0) source. The monoalkynylated derivatives were, in turn, subjected to PdCl$_{2}$ in acetonitrile under reflux to afford either the corresponding 2,4-diaryl-8-bromopyrrolo[3,2,1-\textit{ij}]quinolinones or the 8-(4-hydroxybutanoyl)-substituted quinolinone derivatives, exclusively. Suzuki--Miyaura cross-coupling of the 2-aryl-6-bromo-8-(alkynyl)quinolin-4-ones afforded the 2,4,8-trisubstituted pyrrolo[3,2,1-\textit{ij}]quinolin-6-ones.

Concept Mapping As A Tool For Enhancing Self-Paced Learning In A Distance Scenario, John Allen Richbourg

Walden Dissertations and Doctoral Studies

Researchers have determined that concept maps serve as effective tools in the traditional science classroom. The purpose of this experimental study was to investigate concept mapping as a tool for student knowledge acquisition in 10th grade science for students in distance learning situations. Research questions were designed to investigate the influence of concept mapping on rate and quality of student knowledge acquisition and retention. This study was a pretest-posttest 2-group comparison study, constructivist in nature and based on the theory of cognitive learning. Participants included 36 students in the 10th grade at an inner-city school in the United States. Control …

Dual Effect Of Coumarin Benzimidazolium Ionic Salt Covalently Bonded On A Silica Network, Ahmet Gültek, Davut Aksüt, Turgay Seçki̇n, Emre Bi̇rhanli, Mert Olgun Karataş, Bülent Alici

Turkish Journal of Chemistry

Synthesis of the ionic liquid 1-allyl-3-(4-methyl-7,8-dihydroxy-2H-chromen-2-one) benzimidazolium chloride followed by the conversion of ammonium salts on the imidazole ring hooked to the coumarin group was modified by postmodification of the silica matrix where 3-chloropropyltrimethoxysilane was used as not only a surface modification agent, but also as an ATRP halogen source. The synergetic effect of charged ammonium groups as well as hydroxyl groups present on the coumarin was investigated in terms of ATRP polymerization. The results confirmed that brush polymers show outstanding antibacterial effects against Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa.

Reduction Behavior Of Fenoxaprop-P-Ethyl And Its Voltammetric Determination, Zeki̇ Eş, İbrahi̇m Hüdai̇ Taşdemi̇r

Turkish Journal of Chemistry

The reduction behavior of fenoxaprop-p-ethyl (FNX) was studied on a hanging mercury drop electrode. FNX showed 2 reduction peaks at about --0.7 V and at about --0.9 V versus Ag/AgCl/3.0 M KCl in Britton--Robinson buffer at pH 4.8. Both reductions were irreversible and adsorption was effective. The reduction peaks were assigned to the reduction of C=N to CH--NH and the reduction of C=O to CH--OH. Square-wave voltammetry has been proposed and validated for quantification of FNX in different samples. The linear working range was established as 0.30--15.0 \mu M. Limit of detection and limit of quantification were calculated as 0.07 …

Amperometric Biosensing Of Ethanol Based On Integration Of Alcohol Dehydrogenase With A Pt/Ppy--Pvs/Mb Electrode, Özlem Çolak, Fatma Arslan

Turkish Journal of Chemistry

A novel amperometric ethanol biosensor with alcohol dehydrogenase (ADH) and nicotinamide adenine dinucleotide (NAD^+) on polypyrrole--polyvinylsulfonate (PPy-PVS) film was accomplished. Meldola's blue (MB) was used as a mediator; it can facilitate the electron transfer that involves a chemical interaction between the electrode surface and NADH. Determination of ethanol was carried out by the oxidation of MB at --0.072 V vs. Ag/AgCl. The effects of pH and temperature were investigated and optimum parameters were found to be 7.0 and 40 °C, respectively. There are 2 linear parts at 1.0 \mu M--10.0 \mu M (R^2 = 0.993) and 0.01 mM--0.1 mM (R^2 …

Synthesis And Properties Of Novel Magnetic Nanoparticles Grafted With Nitropyridine-Substituted Calix[4]Arene Derivative As Cr^{6+} Extractant, Serkan Sayin, Vi̇ldan Doğan

Turkish Journal of Chemistry

A new calix[4]arene derivative, 3, which functionalized at the lower rim with 2-(2-aminoethyl amino)-5-nitropyridine, was synthesized and characterized by a combination of FTIR, ^1H NMR, ^{13}C NMR, and elemental analysis. Then the calix[4]arene 3 was grafted onto [3-(2,3-epoxypropoxy)propyl]trimethoxysilane-modified Fe_3O_4-- nanoparticles (EPPTMS-MN) to produce new calixarene-adorned magnetic nanoparticles (MN-DiNoPy-Calix (4)). The structure of the calixarene-adorned magnetic nanoparticles 4 was determined by a combination of FTIR, TEM, and elemental analysis. Moreover, a study regarding the removal of toxic HCr_2O_7^- anion from aqueous solution was also carried out with the calixarene-adorned magnetic nanoparticles in solid--liquid extraction studies.