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Relevant Publications

Environmental Science & Technology Publication (2010)

2008 Final Report

2021 Final Report

Effective Microwave-Assisted Approach To 1,2,3-Triazolobenzodiazepinones Via Tandem Ugi Reaction/Catalyst-Free Intramolecular Azide–Alkyne Cycloaddition, Maryna O. Mazur, Oleksii S. Zhelavskyi, Eugene M. Zviagin, Svitlana V. Shishkina, Vladimir I. Musatov, Maksim A. Kolosov, Elena H. Shvets, Anna Yu. Andryushchenko, Valentyn A. Chebanov

Department of Chemistry: Faculty Publications

A novel catalyst-free synthetic approach to 1,2,3-triazolobenzodiazepinones has been developed and optimized. The Ugi reaction of 2-azidobenzaldehyde, various amines, isocyanides, and acids followed by microwave-assisted intramolecular azide–alkyne cycloaddition (IAAC) gave a series of target heterocyclic compounds in moderate to excellent yields. Surprisingly, the normally required ruthenium-based catalysts were found to not affect the IAAC, only making isolation of the target compounds harder while the microwave-assisted catalyst-free conditions were effective for both terminal and non-terminal alkynes

Non-Adiabatic Quantum Interference In The Ultracold Li + Lina → Li2+ Na Reaction, Brian K. Kendrick, Hui Li, Ming Li, Svetlana Kotochigova, James F.E. Croft, Naduvalath Balakrishnan

Chemistry and Biochemistry Faculty Research

Electronically non-adiabatic effects play an important role in many chemical reactions. However, how these effects manifest in cold and ultracold chemistry remains largely unexplored. Here for the first time we present from first principles the non-adiabatic quantum dynamics of the reactive scattering between ultracold alkali-metal LiNa molecules and Li atoms. We show that non-adiabatic dynamics induces quantum interference effects that dramatically alter the ultracold rotationally resolved reaction rate coefficients. The interference effect arises from the conical intersection between the ground and an excited electronic state that is energetically accessible even for ultracold collisions. These unique interference effects might be exploited …

Subsets Of Adjacent Nodes (Soan): A Fast Method For Computing Suboptimal Paths In Protein Dynamic Networks, Thomas Dodd, Xin-Qiu Joe Yao, Donald Hamelberg, Ivaylo Lvanov

Chemistry Faculty Publications

Suboptimal path analysis in a protein structural or dynamical network becomes increasingly popular for identifying critical residues involved in allosteric communication and regulation. Several software packages have been developed for calculating suboptimal paths, including NetworkView, WISP, and CNAPATH (Bio3D). Although these packages work well for biological systems of moderate sizes, they either dramatically slow down or are subjected to accuracy issues when applied to large systems such as supramolecular complexes. In this work, we develop a new method called SOAN, which implements a modified version of Yen’s algorithm for finding loopless k-shortest paths. Instead of searching the entire protein …

Neglected Nematodes: The Neurolenin Solution, Kevin M. Shea, Steven Williams

Chemistry: Faculty Publications

Over 1 billion people worldwide are affected by Neglected Topical Diseases (NTDs). This group of pathogens encapsulates viruses, bacteria and parasites, and disproportionately affects the world’s poorest and most vulnerable communities in Africa, Asia and Latin America. Lymphatic Filariasis (LF) is an NTD caused by a parasitic nematode infection. The larvae of these filarial nematode worms are transmitted via mosquito bites and disrupt the functioning of the infected individual’s lymphatic system. LF can be caused by three types of filarial worms, Wuchereria bancrofti, Brugia malayi and Brugia timori, which are transmitted by the Culex, Anopheles and Aedes mosquito families. Symptomatic …

Cown Sustains Nitrogenase Turnover In The Presence Of The Inhibitor Carbon Monoxide, Michael S. Medina, Kevin O. Bretzing, Richard A. Aviles, Kiersten M. Chong, Alejandro Espinoza, Chloe Nicole G. Garcia, Benjamin B. Katz, Ruchita N. Kharwa, Andrea Hernandez, Justin L. Lee, Terrence M. Lee, Christine Lo Verde, Max W. Strul, Emily Y. Wong, Cedric P. Owens

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Nitrogenase is the only enzyme capable of catalyzing nitrogen fixation, the reduction of dinitrogen gas (N₂) to ammonia (NH₃). Nitrogenase is tightly inhibited by the environmental gas carbon monoxide (CO). Nitrogen-fixing bacteria rely on the protein CowN to grow in the presence of CO. However, the mechanism by which CowN operates is unknown. Here, we present the biochemical characterization of CowN and examine how CowN protects nitrogenase from CO. We determine that CowN interacts directly with nitrogenase and that CowN protection observes hyperbolic kinetics with respect to CowN concentration. At a CO concentration of 0.001 atm, …

Synthesizing Laccol Based Polymers/Copolymers And Polyurethanes; Characterization And Their Applications, Imalka Marasinghe Arachchilage

USF Tampa Graduate Theses and Dissertations

In modern world research scopes are highly favored the areas of developing new polymer materials which are more integrated with the environment. Synthesizing eco-friendly, bio degradable polymer materials to replace petroleum based synthetic polymers to utilize in radiation hard applications is one of the main objectives of this study. 'Laccol' extracted from Vietnamese lacquer tree (Toxicodendron succedanea) polymerized with other monomers namely styrene and d-limonene (from citrus waste) respectively to develop copolymers via cationic polymerization. Laccol contains hydroxyl phenyl groups that act as radical scavengers, enhancing radiation resistance via their ability to convert excitation energy into non-chemistry inducing energy in …

Comprehensive Chromatographic Profiling Of Cannabis From 23 Usa States Marketed For Medical Purposes, Ramia Z. Al Bakain, Yahya S. Al-Degs, James V. Cizdziel, Mahmoud A. Elsohly

Faculty and Student Publications

In this research, cannabis varieties represent 23 USA States were assayed by GC-FID to generate their complex chemical profiles informative for plants clustering. Results showed that 45 cannabinoids and terpenoids were quantified in all plant samples, where 8 cannabinoids and 18 terpenoids were identified. Among organics, Δ9-THC, CBN (cannabinoids) and Fenchol (terpenoid) not only showed the highest levels overall contents, but also were the most important compounds for cannabis clustering. Among States, Washington, Oregon, California and Hawaii have the highest cannabis content. GC-FID data were subjected to PCA and HCA to find (1) the variations among cannabis chemical profiles as …

Crystal Structure Of Pimecrolimus Form B, C43h68clno11, Shivang Bhaskar '20, Joseph T. Golab, James A. Kaduk, Amy M. Gindhart, Thomas N. Blanton

Student Publications & Research

No abstract provided.

Blood Driven Biopower Cells: Acquiring Energy From Reverse Electrodialysis Using Sodium Concentrations From The Flow Of Human Blood, Efecan Pakkaner, Chase Smith, Christina Trexler, Jamie Hestekin, Christa Hestekin

Chemical Engineering Faculty Publications and Presentations

With the growth of the healthcare industry, small scale power sources are needed to support advancements in medical implants, artificial organs, and sensors throughout the body. However, it remains a challenge to find safe, reliable, and stable power sources for these devices. In this study, a miniaturized reverse electrodialysis (RED) biopower cell design using physiological salinity concentration differences between renal bloodstreams is explored for its potential to be used as a power supply for implantable medical devices. Two small scale RED devices produced consistent power for up to three to ten days, depending on the device design. A two-fold decrease …

Crystal Structure Of (E)-Doxepin Hydrochloride, C19h22nocl, Jerry Hong '20, Joseph T. Golab, James A. Kaduk, Amy M. Gindhart, Thomas N. Blanton

Student Publications & Research

No abstract provided.

Electronically Excited States Of Closed-Shell, Cyano-Functionalized Polycyclic Aromatic Hydrocarbon Anions, Taylor J. Santaloci, Ryan C. Fortenberry

Faculty and Student Publications

Few anions exhibit electronically excited states, and, if they do, the one or two possible excitations typically transpire beyond the visible spectrum into the near-infrared. These few, red-shifted electronic absorption features make anions tantalizing candidates as carriers of the diffuse interstellar bands (DIBs), a series of mostly unknown, astronomically ubiquitous absorption features documented for over a century. The recent interstellar detection of benzonitrile implies that cyano-functionalized polycyclic aromatic hydrocarbon (PAH) anions may be present in space. The presently reported quantum chemical work explores the electronic properties of deprotonated benzene, naphthalene, and anthracene anions functionalized with a single cyano group. Both …

Characterization Of A Broadly Specific Cadaverine N-Hydroxylase Involved In Desferrioxamine B Biosynthesis In Streptomyces Sviceus, Lesley Ann Giddings, George T. Lountos, Kang Woo Kim, Matthew Brockley, Danielle Needle, Scott Cherry, Joseph E. Tropea, David S. Waugh

Chemistry: Faculty Publications

N-hydroxylating flavin-dependent monooxygenases (FMOs) are involved in the biosynthesis of hydroxamate siderophores, playing a key role in microbial virulence. Herein, we report the first structural and kinetic characterization of a novel alkyl diamine N-hydroxylase DesB from Streptomyces sviceus (SsDesB). This enzyme catalyzes the first committed step in the biosynthesis of desferrioxamine B, a clinical drug used to treat iron overload disorders. X-ray crystal structures of the SsDesB holoenzyme with FAD and the ternary complex with bound NADP+ were solved at 2.86 Å and 2.37 Å resolution, respectively, providing a structural view of the active site environment. SsDesB crystallized as a …

Oxygen Binding Thermodynamics Of Human Hemoglobin In The Red Blood Cell, Kyle K. Hill

Department of Chemistry: Dissertations, Theses, and Student Research

We report for the first time the binding constants and Hill numbers for oxygen in the red blood cell under physiological conditions. When compared to our results for hemoglobin in solution, our results show conclusively that hemoglobin binds oxygen more tightly and with lower co-operativity when packed in the red blood cell. At 18°C, these differences are striking: the respective half-saturation values are 15.57 µM (in red blood cells) and 18.83 µM (in solution), with corresponding Hill numbers of 2.475 (in red blood cells) and 2.949 (in solution). The optical complications that arise from high turbidity of red blood cell …

College Of Natural Sciences Newsletter, March 2021, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Volume 2. Issue 3

Contents:

Page 1 Dean's Message
Page 2-3 Awards and Recognition
Page 4 Student Club Spotlight: MICROBIOLOGY CLUB
Page 5 Research Spotlight: Dr. Chakravarty
Page 6 Open PRAIRIE Data; Grants Awarded in CNS; Research Collquia
Page 7 A Busy Month in Review; Media Coverage of the College

High-Throughput Screen For Inhibitors Of The Type Iv Pilus Assembly Atpase Pilb, Keane J. Dye, Nancy J. Vogelaar, Pablo Sobrado, Zhaomin Yang

Chemistry Faculty Research & Creative Works

The bacterial type IV pilus (T4P) is a prominent virulence factor in many significant human pathogens, some of which have become increasingly antibiotic resistant. Antivirulence chemotherapeutics are considered a promising alternative to antibiotics because they target the disease process instead of bacterial viability. However, a roadblock to the discovery of anti-T4P compounds is the lack of a high throughput screen (HTS) that can be implemented relatively easily and economically. Here, we describe the first HTS for the identification of inhibitors specifically against the T4P assembly ATPase PilB in vitro. Chloracidobacterium thermophilum PilB (CtPilB) had been demonstrated to have robust ATPase …

Electronic Transitions In Rb2+ Dimers Solvated In Helium, Simon Albertini, Paul Martini, Arne Schiller, Harald Schöbel, Elham Ghavidel, Milan Ončák, Olof E. Echt, Paul Scheier

Faculty Publications

We have measured depletion spectra of the heteronuclear (⁸⁵Rb⁸⁷Rb⁺) dimer cation complexed with up to 10 He atoms. Two absorption bands are observed between 920 and 250 nm. The transition into the repulsive 1²Sigma_u⁺ state of HeRb₂⁺ gives rise to a broad feature at 790 nm (12650 cm^–1); it exhibits a blueshift of 98 cm^–1 per added He atom. The transition into the bound 1 ²Pi_u state of HeRb₂⁺ reveals vibrational structure with a band head at < 15522 cm^–1, a harmonic …

Soil Quality Indices As Affected By Long-Term Burning, Irrigation, Tillage, And Fertility Management, Helen C.S. Amorim, Amanda Ashworth, Kristofor R. Brye, Brian J. Wienhold, Mary C. Savin, Phillip R. Owens, Sergio Silva

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Understanding the impacts of long-term agricultural practices on soil quality (SQ) is key for sustaining agroecosystem productivity. This study investigated conventional and no-tillage (NT), residue burning and no burning, residue level (high and low), and irrigation (irrigated and dryland) effects on soil properties, SQ, and crop yields following 16 yr of a wheat (Triticum aestivum L.)–soybean [Glycine max (L.) Merr.] double-crop system via the Soil Management Assessment Framework (SMAF). A field experiment was conducted in the Lower Mississippi River Delta region on a silt-loam soil. Bulk density, soil organic C (SOC), total N (TN), pH, electrical conductivity (EC), …

Achieving Superlubricity With 2d Transition Metal Carbides (Mxenes) And Mxene/Graphene Coatings, S. Huang, K. C. Mutyala, A. V. Sumant, Vadym Mochalin

Chemistry Faculty Research & Creative Works

Two-dimensional (2D) materials have demonstrated unique friction and antiwear properties unmatched by their bulk (3D) counterparts. A relatively new, large and quickly growing family of two-dimensional early transition metal carbides and nitrides (MXenes) present a great potential in different applications. There is a growing interest in understanding the mechanical and tribological properties of MXenes, however, no report of MXene superlubricity in a solid lubrication process at the macroscale has been presented. Here we investigate the tribological properties of two-dimensional titanium carbide (Ti₃C₂) MXene deposited on SiO₂-coated silicon (Si) substrates subjected to wear by sliding …

Sulfur Anions: Comments Upon Structure, Charles A. Kingsbury

Department of Chemistry: Faculty Publications

This work emphasizes the need for solvent simulation as well as a counterion in calculations concerning anions, although optimization may be difficult. Solvent and counterion both play a large role in conformation of the ion. Part of the reason for the success of sulfur anions in chemical reactions may be the ability of sulfone oxygen(s) to coordinate with the counterion (usually lithium). The “solvent” partially dissociates lithium from the carbanion center.

The Effect Of Amino Acids And Molar Peroxide Ratio On The Oxidation Of 2,4 Dinitroanisole In An Ultraviolet Light Emitting Diode/H2O2 Advanced Oxidation Process, Jeffry P. Hart

Theses and Dissertations

2,4 Dinitroanisole (DNAN) is an organic insensitive munition that is a likely candidate to replace trinitrotoluene (TNT) for a variety of purposes. Advanced Oxidation Processes (AOPs) are a promising method that have the potential to reduce a variety of persistent chemicals, however, the performance of these systems may be degraded by co-contaminants in the influent. In this contribution, DNAN, with casamino acids as a co-contaminant, was oxidized with Ultraviolet (UV) Light Emitting Diodes (LEDs) with hydrogen peroxide (H₂O₂) in an AOP in a laboratory. The UV/ H₂O₂ AOP was capable of degrading DNAN …

Appearance Of New Photoluminescence Peak And Spectral Evolution Of Eu3+ In La2zr2o7 Nanoparticles At High Pressure, Santosh K. Gupta, Hisham Abdou, Yuanbing Mao

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

Lots of efforts have been vested recently on tuning the structure and optical properties, particularly for the luminescent nanophosphors. High pressure in that direction has shown great potential to tune the performance of nanophosphors. However, very little attention has been paid on tuning the optical properties of technologically important La2Zr2O7 (LZO) pyrochlore nanoparticles (NPs) and its doped counterpart La2Zr2O7:Eu3+ (LZOE) NPs under elevated pressure. Equally little effort has been given on local structure evolution of Eu3+ ion as a function of pressure in the doped LZOE NPs. Here in this work, LZO depicted strong oxygen vacancy blue emission under ambient …

Preparations And Electrocatalytic Ethanol Properties Of Palladium Intercalated Hydrotalcite, Shou-Xun Hu, Liang Li, Jun-Hao Yang, Liu-Qiang Li, Zhi-Hao Jin

Journal of Electrochemistry

High-performance electrocatalysts play a vital role in the commercial application of direct fuel cells. Current anode materials still have such problems as low activity, easy poisoning and high cost. In this study, a new type of nano- palladium (Pd) catalyst was prepared by dipping method using layered double hydroxides (LDHs) as the carrier. X-ray diffractometer, scanning electron microscope (SEM), inductively coupled plasma mass spectrometer (ICP-MS), energy spectrometer, transmission electron microscope (TEM), cyclic voltammetry, chronoamperometry and electrochemical impedance spectroscope were used to analyze the structure and electrocatalytic performance of the catalyst. The results showed that the newly prepared Pd/Mg-Al-LDHs still maintained …

Theoretical Study On Electrical Properties Of Molecular Junctions Of Viologen Derivatives, Zhuan-Yun Cai, Jia Liu, Si-Yuan Guan, De-Yin Wu, Zhong-Qun Tian

Journal of Electrochemistry

In this paper, the electrical properties of molecular junctions formed N,N′-bis(4-thioalkyl)-4,4′-bipyridinium (viologen) moiety between two gold (Au) electrodes have been investigated by combining density functional theory and non-equilibrium Green’s functional approach. To modulate the viologen molecule to be a cation with one and two positive charges (V⁺ and V²⁺), we introduce one and two trifluoroacetic acid ions (TFA^-) around the molecule, respectively. The valence states of V⁺ and V²⁺ are confirmed by checking Mulliken and NBO charges. Then the relationship between molecular conductance and electronic structures of the neutral state …

Preparation Of Pdcoir Tetrahedron Nanocatalysts And Its Performance Toward Ethanol Oxidation Reaction, Zhi-Yuan Yu, Rui Huang, Jie Liu, Guang Li, Qian-Tong Song, Shi-Gang Sun

Journal of Electrochemistry

As a new energy conversion device, direct ethanol fuel cells (DEFCs) are widely concerned because of their remarkable advantages such as high theoretical energy density and wide fuel sources. However, the rapid development of DEFCs has been severely impeded due to the sluggish kinetic process and toxic intermediates especially in their anodic reactions. Palladium (Pd)-based materials are considered to be excellent anode catalysts for DEFCs, especially under alkaline conditions. And further improving their performance is an important direction to promote the development of DEFCs. Surface structure and composition are the key factors affecting the performance of catalysts which can be …

Preparation And Performance Investigation Of Li-Sgo Doped Semi-Ipns Porous Single Ion Conducting Polymer Electrolyte, Yun-Feng Zhang, Jia-Ming Dong, Chang Tan, Shi-Kang Huo, Jia-Ying Wang, Yang He, Ya-Ying Wang

Journal of Electrochemistry

Herein, the lithiated sulfonated graphene oxide (Li-SGO) was successfully prepared via three steps by sulfonation of graphene oxide with 3-merraptnpropylt rimethnxysilane, oxidation of thiol into sulfonate with hydrogen peroxide and lithiation of sulfonate with aqueous lithium hydroxide. The as-prepared Li-SGO was then introduced into the semi-interpenetrating networks of single ion conducting polymer electrolyte (Li-SGO-FPAS) and poly vinylidenefluoride-hexafluoro propylene (PVDF-HFP) binder by in-situ polymerization to fabricate the porous single ion conducting polymer electrolyte membrane (Li-SGO-po-FPAS) generated from the poor compatibility between aromatic Li-SGO-FPAS and aliphatic PVDF-HFP binder. The key properties such as morphology, porosity, solvent uptake, mechanical …

Combined Applications Of Photocurrent Spectroscopy, Photoluminescence Spectroscopy And Uv-Vis Spectroscopy For Nano-Semiconductor Based Photoelectric Devices, Si-Da Bian, Jian-Zhang Zhou, Zhong-Hua Lin

Journal of Electrochemistry

The electronic structures and properties of nano-semiconductors are quite different from those of bulk semiconductors due to the nano-size effect (such as quantum size effect). Moreover, when the nano-semiconductor materials are deposited onto the substrate to construct a device, their electronic properties are also affected by the substrate or other components, which may lead to different performances of nano-semiconductors based photoelectric devices, and consequently, different corresponding characterization methods are needed. The combination of photocurrent spectroscopy, photoluminescence spectroscopy with UV-Vis absorption spectroscopy can provide a more comprehensive characterization for the electronic properties and photoelectrochemical performances of nano-semiconductors in photoelectric devices. Our …

Influence Of Resveratrol On Performance Of Long-Term Storage’S Lithium-Ion Battery Electrolyte, Lei Zhang, Xu-Ping Zhang, Si-Wei Zhang, Quan-Chao Zhuang

Journal of Electrochemistry

Electrolyte of lithium-ion battery usually goes through processes of filling, transportation and storage from the completion of manufacture to the use. Understanding the influence of long-term storage process on performance of lithium-ion battery electrolyte is of theoretical significance for production of lithium-ion battery. Scanning electron microscope (SEM) images showed that the solid electrolyte interface (SEI) film formed on the surface of the graphite electrode was thicker in the base electrolyte after 6 months of storage. The charge/discharge test results showed that the reversible cycle capacity and cycle stability (capacity retention rate) of graphite electrode decreased significantly after 6 months of …

Research Progress In Electrodeposition Technology Of Titanium-Based Iridium Oxide Electrode, Dan-Dan Wu, Xu Wu

Journal of Electrochemistry

Titanium-based iridium oxide electrode has been widely used in various fields, such as electrocatalytic oxidation, biomedical applications, hydrometallurgical metal recovery, electro-osmotic dewatering, etc. At present, it is mainly prepared by traditional thermal decomposition method, however, which has high cost, cumbersome process, mainly relying on manual labor and cannot be mass-produced yet. It is, therefore, urgently necessary to explore new preparation technologies by focusing on electrodeposition technology, with technological characteristics such as eco-friendly and sustainable development. This article systematically discusses the research progress in iridium oxide electrodeposition preparation technology from the aspects of deposition solution formulation, base material selection and treatment, …

Preparations And Electrochemical Properties Of Bc/Coni2S4@Ppy Flexible Composites For Supercapacitors, Si-Yuan Peng, Shi-Run Yang, Jing-Hong Zhou, Zhi-Jun Sui, Tao Zhang, Yi Shi, Xing-Gui Zhou

Journal of Electrochemistry

Flexible supercapacitor is one of the most promising energy storage devices for portable and wearable electronic products due to its advantages of high power density, fast charging and long cycle life. Therefore, self-supporting flexible electrode materials with high performance have attained more and more attention both in academia and in industry recently. In this work, using bacterial cellulose (BC) as a flexible substrate, the bacterial cellulose/nickel-cobalt sulfide@polypyrrole (BC/CoNi₂S₄@PPy) flexible composites with three-dimensional porous network and good conductivity were prepared by a combined solvothermal-in-situ polymerization-vacuum filtration method. The samples were characterized by X-ray diffraction, …