Physical Sciences and Mathematics Commons^™

Chromatography-Mass Spectroscopy Analysis Of Native American Pottery For Maple Syrup Residue [Poster], Alexis Wirtz, Joshua Sebree Ph.D., Donald Gaff Ph.D.

Summer Undergraduate Research Program (SURP) Symposium

The research conducted regards whether or not Native Americans understood how to create maple syrup before the influence of Europeans. Through the usage of Gas Chromatography-Mass Spectroscopy (GC-MS), the identity of different maple syrup organic residues within pottery can be determined.¹ These organic residues tell us more about Native American history and culture. An analysis of organic residues was performed on the following types of pottery: proof of concept and weathered (an analog of the proof of concept). Organic residues were able to be identified within the proof of concept but not in the weathered pottery. This research also …

Using Atomic Force Microscopy To Study Dna And Rad51 Protein Interaction, Samrin Shahnaz, Justin Peters Ph.D.

Summer Undergraduate Research Program (SURP) Symposium

Recombinase proteins, such as RAD51, play a central role in repairing double-strand breaks of DNA through the process of homologous recombination. In this project, Atomic Force Microscopy (AFM) was used to generate scans of RAD51 proteins bound to double-stranded DNA. Due to the cooperativity of RAD51 binding, we observed a nucleation effect where RAD51 proteins generally tended to bind to DNA that already had other RAD51 proteins bound.

Attitudes Toward The Chemistry Laboratory Learning Environment Using Different Pedagogies And Assessment Protocols, Lydia Richardson, Dawn Del Carlo Ph.D.

Summer Undergraduate Research Program (SURP) Symposium

The Science Writing Heuristic (SWH) and Argument Driven Inquiry (ADI) are evidence-based laboratory approaches that emphasize the process of scientific argumentation (Burke et al., 2006; Rudd et al., 2001; Walker et al., 2011). The University of Northern Iowa utilized the SWH approach for over 10 years until research indicated that the cognitive load associated with the pre-lab, specifically, hindered students’ ability to participate in authentic scientific inquiry for the rest of the laboratory experiment (Bonde & Del Carlo, 2018). In response to this, a hybrid model of instruction integrating elements of both the SWH and ADI laboratory approaches was created …

Extracting Lithium Using The Steric Bulk Of An Aminimide Functional Group, Jacob Parker, Martin Chin Ph.D.

Summer Undergraduate Research Program (SURP) Symposium

An aminimide is a zwitterionic group containing a cationic nitrogen bonded to an anionic nitrogen. The goal of this project was to use the steric bulk and electronic properties of the aminimide to block other species in a brine solution such as potassium, and selectively pick up lithium. To test this, polymethacrylate beads which contain carboxyl groups were modified to the desired aminimide. Three different aminimide groups were tested, a trimethylaminimide, aminopyridiniumaminimide, and a triethylaminimide. The modified beads would be introduced to a solution containing lithium and the lithium concentration was measured before and after exposure to the beads using …

Using An Aminimide Polymer To Extract Lithium From A Brine Solution, Austin Heidbreder, Martin Chin Ph.D.

Summer Undergraduate Research Program (SURP) Symposium

Fast lithium isolation from water partly containing lithium ions would be an improvement over the current method of obtaining lithium in lithium mining water operations. The aminimide functional group can be used to selectively bind to lithium cations to extract lithium from brine. To characterize this uptake, the concentration of water containing lithium was measured with atomic absorption spectroscopy before and after the solution has been exposed to a polymer with the aminimide functional group. Three different polymers were used: trimethyl EGDM polymer, trimethyl TMPTA polymer, and the triethyl TMPTA polymer. Of the three, the trimethyl TMPTA polymer seemed to …

61st Annual Rocky Mountain Conference On Magnetic Resonance

Rocky Mountain Conference on Magnetic Resonance

Final program, abstracts, and information about the 61st annual meeting of the Rocky Mountain Conference on Magnetic Resonance, co-endorsed by the Colorado Section of the American Chemical Society and the Society for Applied Spectroscopy. Held in Copper Mountain, Colorado, July 25-29, 2022.

Noninteracting V-Representable Subspaces Of Orbitals In The Kohn–Sham Method, Viktor N. Staroverov

Chemistry Publications

The notion of noninteracting v-representability is extended from electron densities to finite-dimensional linear subspaces of orbitals. Unlike electron densities, orbital subspaces can be tested for noninteracting v-representability using a transparent necessary condition: the subspace must be invariant under the action of some one-electron Kohn–Sham Hamiltonian. This condition allows one to determine in principle, and sometimes in practice, whether a given one-electron basis set can represent an N-electron density within the Kohn–Sham method and to find the corresponding Kohn–Sham effective potential v if it exists. If the occupied Kohn–Sham orbitals form linearly independent products, then their subspace is …

Electrodeposition Mechanism And Process Of A Novel Cyanide-Free Gold Sulfite Bath, Jia-Qiang Yang, Lei Jin, Wei-Qing Li, Zhao-Yun Wang, Fang-Zu Yang, Dong-Ping Zhan, Zhong-Qun Tian

Journal of Electrochemistry

A novel cyanide-free gold sulfite process is introduced in this paper. In the bath, chloauric acid was directly employed as the main salt, and hydroxyethylidene diphosphonic acid (HEDP) was used as the stabilizer and coating grain refiner. The bath stability, the gold coating morphology and the mechanism of gold electrodeposition were studied in detail. The results showed that HEDP could significantly improve the bath stability. Moreover, the grains of the gold coating obtained from the gold sulfite bath without HEDP was rod-like, which grew gradually with the increasing of the deposition time, resulting in that the appearance of the coating …

Research Progress Of Copper Electrodeposition Filling Mechanism In Silicon Vias, Yun-Na Sun, Yong-Jin Wu, Dong-Dong Xie, Han Cai, Yan Wang, Gui-Fu Ding

Journal of Electrochemistry

Aiming at the electroplating filling problem of deep via TSV (through silicon via) interconnection, the multi-compatible integrated manufacturing technology team at the Shanghai Jiao Tong University has completed the numerical solution of the equations and realized the numerical simulation of TSV filling mode by applying the finite element method with arbitrary Lagrange Euler algorithm. The filling mechanisms of blind vias, the butterfly filling form for the through vias and the simultaneous filling mode of vias with different aspect ratios are analyzed by simulation, contributing to the parameter optimization and sample manufacturing. The effects of electroplating current density and heat treatment …

Preface To Special Issue On Electronic Electroplating, Zhi-Dong Chen, Chong Wang, Wei He, Ming Li

Journal of Electrochemistry

No abstract provided.

Mechanism And Application Of Nickel Nano-Cone By Electrodeposition On A Flexible Substrate, Xiu-Ren Ni, Ya-Ting Zhang, Chong Wang, Yan Hong, Yuan-Ming Chen, Yuan-Zhang Su, Wei He, Xian-Ming Chen, Ben-Xia Huang, Zhen-Lin Xu, Yi-Feng Li, Neng-Bin Li, Yong-Jie Du

Journal of Electrochemistry

Nano-array structure possesses promising prospect in power supply, optical device and electronic manufacturing. In this paper, a black nickel nano-cone array was prepared on a flexible substrate by galvanostatic deposition and the corresponding factors involved in the fabrication of nickel nano-cone array was explored. Experimental results showed that a large current density and low main salt concentration were not favored to the formation of cone nickel structure. It was also found that ammonium chloride, as the crystal modifier, was crucial to deposit the uniform nano-cone array. In addition, the growth mechanism of nickel nano-cone was further studied by molecular dynamics …

Electrodeposition Of Functional Epitaxial Films For Electronics, Kui Huang, Rong-Jiao Huang, Su-Qin Liu, Zhen He

Journal of Electrochemistry

Electrodeposition is a solution-based synthesis technique that can be used to fabricate various functional materials on conductive or semiconductive substrates under ambient conditions. Electrodeposition is usually triggered by an artificial electric stimulation (i.e., applied potential/current) to the substrate to oxidize or reduce ions, molecules, or complexes in the deposition solution layer near the substrate surface, which drives this solution layer to depart from its thermodynamic equilibrium and consequently causes the assembly of targeted deposits on the substrate. During electrodeposition, many experimental parameters could affect the properties of the deposits in different ways. To date, many elements (both metals and nonmetals), …

Electrochemical Deposition Of Copper Pillar Bumps With High Uniformity, Bai-Zhao Tan, Jian-Lun Liang, Zi-Liang Lai, Ji-Ye Luo

Journal of Electrochemistry

Electrochemical deposition of copper pillar bumps (CPBs) is one of the key technologies for the advanced packaging. In this study, the effects of the additive concentration, the electrolyte convection, the current density, and the electroplating system on the uniformity of the CPBs have been systematically investigated. The results showed that the profiles of the CPBs were mainly determined by the additive concentration, the bath convection and the current density, while the heights of the CPBs were mainly affected by the electroplating system. For the CPBs profiles, it was found that the low leveler concentration and high current density would generally …

Investigation Of Through-Hole Copper Electroplating With Methyl Orange As A Special Leveler, Jia-Ying Xu, Shou-Xu Wang, Yuan-Zhang Su, Yong-Jie Du, Guo-Dong Qi, Wei He, Guo-Yun Zhou, Wei-Hua Zhang, Yao Tang, Yu-Yao Luo, Yuan-Ming Chen

Journal of Electrochemistry

Methyl Orange (MO) with two kinds of functional groups can act as both an accelerator and an inhibitor, which has been used as a special leveler to simplify the electroplating additive system in the through-hole (TH) copper electroplating experiments. In this work, the role of MO in TH electroplating is characterized by molecular dynamics simulations and quantum chemical calculations. It is suggested that MO can spontaneously flatten the copper surface and be well adsorbed on the cathode surface, which inhibit the copper electrodeposition on the cathode. Electrochemical behavior of MO was evaluated by galvanostatic measurements (GM) and cyclic voltammetry (CV) …

Research Progress In Electroless Cobalt Plating And The Bottom-Up Filling Of Electroless Plating, Yu Shen, Bing-Bing Li, Yi Ma, Zeng-Lin Wang

Journal of Electrochemistry

With the continuous improvement of semiconductor integration, the resistivity of copper interconnect lines increases rapidly. When the width of the interconnect line is close to 7 nm, the resistivity of copper becomes the same as that of cobalt. International Business Machines Corporation (IBM) and Advanced Semiconductor Incorporation (ASI) have used cobalt to replace copper as a next-generation interconnect material. However, the fabrication of the cobalt seed layer and the super filling of electroplating cobalt for the 7 nm via-holes have been still the large challenge. Electroless plating is a very simple method to form a seed layer on the surface …

Effect Of Corrosion Inhibitors On Copper Etching To Form Thick Copper Line Of Pcb In Acidic Etching Solution, Xiao-Li Wang, Wei He, Xian-Ming Chen, Hong Zeng, Yuan-Zhang Su, Chong Wang, Gao-Sheng Li, Ben-Xia Huang, Lei Feng, Gao Huang, Yuan-Ming Chen

Journal of Electrochemistry

The chemical compounds of 2-mercaptobenzothiazole (2-MBT), benzotriazole (BTA) and phenoxyethanol (MSDS) as corrosion inhibitors were used to inhibit the copper etching to form the thick copper line of PCB in the acidic etching solution. The inhibition status was characterized with contact angle measurement, electrochemical test and etch factor calculation, while the corrosion morphology of copper surface was studied by scanning electron microscope. The adsorption mechanism of corrosion inhibitors on copper surface is analyzed by molecular dynamics and quantum chemistry calculations. The results indicated that the synergistic function of the two inhibitors could effectively promote their adsorption on the copper surface …

Thioester Synthesis By A Designed Nickel Enzyme Models Prebiotic Energy Conversion, A. C. Manesis, A. Yerbulekova, Jason M. Shearer, H. S. Shafaat

Chemistry Faculty Research

The formation of carbon-carbon bonds from prebiotic precursors such as carbon dioxide represents the foundation of all primordial life processes. In extant organisms, this reaction is carried out by the carbon monoxide dehydrogenase (CODH)/acetyl coenzyme A synthase (ACS) enzyme, which performs the cornerstone reaction in the ancient Wood-Ljungdahl metabolic pathway to synthesize the key biological metabolite, acetylCoA. Despite its significance, a fundamental understanding of this transformation is lacking, hampering efforts to harness analogous chemistry. To address these knowledge gaps, we have designed an artificial metalloenzyme within the azurin protein scaffold as a structural, functional, and mechanistic model of ACS. We …

The Interaction Of Deep Eutectic Solvents With Pristine Carbon Nanotubes And Their Associated Defects: A Density Functional Theory Study, Hamid Reza Ghenaatian, Mehdi Shakourian-Fard, Ganesh Kamath, John F. Trant, Farouq S. Mjalli

Chemistry and Biochemistry Publications

In this study, the interaction of four deep eutectic solvents (DESs): [Choline chloride][Urea] ([ChCl][U]), [Choline chloride][Ethylene glycol] ([ChCl][EG]), [Choline chloride][Glycerol] ([ChCl][Gly]) and [Choline chloride][Benzoic acid] ([ChCl][BA]), with pristine carbon nanotube (CNT) and its defects: double-vacancy and Stone–Wales structures (CNT-DV and CNT-SW) is investigated using density functional theory (DFT) calculations. The geometry optimization, electronic property calculations, noncovalent interaction analysis and optical properties of the DES@nanotube complexes were carried out at the M06-2X/cc-pVDZ level of theory. The adsorption energy (Eads) calculations show that the presence of the DV and SW defects on the CNT increases the adsorption strength of the DESs, DES@CNT-SW …

Oxygen Speciation In Potassium Silicate And Potassium Aluminosilicate Glasses: Insights From X-Ray Photoelectron Spectroscopy, Ryan Sawyer

Electronic Thesis and Dissertation Repository

In a geological context, glasses are useful analogues for silicate melts as they are more readily studied in the laboratory using a wide range of techniques that are impractical for molten liquids. Understanding the structure of binary silicate glasses can help us understand more about the magmatic processes that affect terrestrial planetary bodies.

Potassium silicate glasses ranging in composition from 10 mol% to 35 mol% K₂O were studied using X-ray Photoelectron Spectroscopy (XPS). From high resolution O 1s XPS spectra, Bridging Oxygen (BO) mole fractions were calculated and compared with those of previous ²⁹Si MAS NMR studies. …

Nmr And Metabolomics—A Roadmap For The Future, David S. Wishart, Leo L. Cheng, Valérie Copié, Arthur S. Edison, Hamid R. Eghbalnia, Jeffrey C. Hoch, Goncalo J. Gouveia, Wimal Pathmasiri, Robert Powers, Tracey B. Schock, Lloyd W. Sumner, Mario Uchimiya

Chemistry Department: Faculty Publications

Metabolomics investigates global metabolic alterations associated with chemical, biological, physiological, or pathological processes. These metabolic changes are measured with various analytical platforms including liquid chromatography-mass spectrometry (LC-MS), gas chromatographymass spectrometry (GC-MS) and nuclear magnetic resonance spectroscopy (NMR). While LC-MS methods are becoming increasingly popular in the field of metabolomics (accounting for more than 70% of published metabolomics studies to date), there are considerable benefits and advantages to NMR-based methods for metabolomic studies. In fact, according to PubMed, more than 926 papers on NMR-based metabolomics were published in 2021—the most ever published in a given year. This suggests that NMR-based metabolomics …

Bbt Acoustic Alternative Top Bracing Cadd Data Set-Norev-2022jun28, Bill Hemphill

STEM Guitar Project’s BBT Acoustic Kit

This electronic document file set consists of an overview presentation (PDF-formatted) file and companion video (MP4) and CADD files (DWG & DXF) for laser cutting the ETSU-developed alternate top bracing designs and marking templates for the STEM Guitar Project’s BBT (OM-sized) standard acoustic guitar kit. The three (3) alternative BBT top bracing designs in this release are
(a) a one-piece base for the standard kit's (Martin-style) bracing,
(b) 277 Ladder-style bracing, and
(c) an X-braced fan-style bracing similar to traditional European or so-called 'classical' acoustic guitars.

The CADD data set for each of the three (3) top bracing designs includes …

Designing Dynamic And Degradable Polymeric Materials With Thiol-X Chemistries, Reese Sloan

Dissertations

With plastic production poised to increase in coming years, there arises a need to develop new polymeric materials designed to combat the global pollution crisis. A commonly utilized approach in addressing this challenge is to employ a responsive functional moiety into the polymer architecture. Thiol-X reactions, a commonly utilized class of “click” reactions, have garnered broad implementation in new stimuli-responsive materials. This work specifically focuses on utilizing radical-mediated thiol-ene coupling and base-catalyzed thiol-isocyanate reactions to develop a library of ternary thiol-ene/thiourethane covalent adaptable networks (CANs) and hydrolytically labile poly(thioether ketal) thermoplastics. CANs are a class of network materials capable of …

Investigating The Influence Of Synthetic Environments On The Electronic Structure And Luminescence Of Cr-Doped Zinc Gallate, Xincheng Li

Electronic Thesis and Dissertation Repository

Cr doped ZnGa₂O₄ (Cr-ZGO) has shown potential in the field of bioimaging. To achieve the nano-size suiting for bioimaging, Cr-ZGO is normally synthesized using a hydrothermal method. There are few studies on how the hydrothermal conditions influence the structure and optical properties of the Cr-ZGO. The first two parts of this thesis study how different hydrothermal temperatures and pH environments will affect the optical properties of Cr-ZGO by photoluminescence spectroscopy. By combining the electronic structure information extracted from X-ray absorption near-edge structures (XANES) and extended X-ray absorption fine structure (EXAFS), a relationship among hydrothermal conditions, optical properties …

Identification Of Fire-Retardant Chemical Treatments Via Instrumental Analysis, Caitlin Dillon

Discovery Day - Prescott

Fiber trace evidence is one of the most common forms of evidence found at a crime scene; these evidentiary items often have unique flame retardant chemical compositions or volatile chemical signatures. The retardant compounds can be used as an additional piece of evidence to trace a fiber from a victim to a source sample. This analytical comparison will require the use of specialized equipment available at the Prescott campus of Embry-Riddle Aeronautical University. This equipment and instrumentation includes scanning electron microscopy with energy dispersive spectroscopy (SEM/EDS), Fourier-transform infrared spectroscopy (FTIR), and gas chromatography-mass spectroscopy (GC/MS), using both liquid and volatile …

Monitoring Environmental Trends In Levels Of Influenza Virus And Sars-Cov-2 In Prescott, Az, Jade Blackert, Daniella Cowles

Discovery Day - Prescott

Every year, the Centers for Disease Control and Prevention and state health agencies collect surveillance data for cases of influenza. During the flu season of 2019, SARSCoV- 2, which causes the symptoms known as COVID-19, caused a global pandemic. In turn, the surveillance and testing data showed a dramatic drop in influenza case numbers compared to previous years. Influenza is one of the deadliest viruses in human history, so it seems unlikely that this drastic change would occur due to the emergence of a similar virus. This research is designed to show that the prevalence of influenza in the community …

Growth Outcomes Of Pseudomonas Aeruginosa Inhibitor Of Vertebrate Lysozyme Knockouts In Conditions Mimicking The Cystic Fibrosis Lung Environment, Amani Gaddy

Master of Science in Chemical Sciences Theses

Pseudomonas aeruginosa (PA) is a Gram-negative bacterium, often found in cystic fibrosis (CF) patients and can lead to the decline of lung functioning and premature death in 80% of infected patients when microcolonies form within the mucin of the lung. Due to its major capacity for antibiotic resistance, an alternative strategy towards defending against the bacterial invasion of PA is by the antibacterial activity of our own innate immune system with use of elements such as lysozyme. Pseudomonas aeruginosa inhibitor of vertebrate lysozyme class 1 (Ivyp1) is a periplasmic protein produced by gram-negative bacteria that inhibits the enzymatic activity of …

Investigation On The Synthesis, Application And Structural Features Of Heteroaryl 1,2-Diketones, Robert J. Wehrle, Alexander Rosen, Thu Vu Nguyen, Kalyn Koons, Eric Jump, Mason Bullard, Natalie Wehrle, Adam Stockfish, Patrick M. Hare, Abdurrahman Atesin, Tülay A. Ateşin, Lili Ma

Chemistry Faculty Publications and Presentations

A set of unsymmetrical heteroaryl 1,2-diketones were synthesized by a heteroarylation/oxidation sequence with up to 65% isolated yields. Palladium catalyst XPhos Pd G4 and SeO2 were the key reagents used in this methodology, and microwave irradiation was utilized to facilitate an efficient and ecofriendly process. The application of heteroaryl 1,2-diketones is demonstrated through the synthesis of an unsymmetrical 2-phenyl-3-(pyridin-3-yl)quinoxaline (5a) from 1-phenyl-2-(pyridin-3-yl)ethane-1,2-dione (4a). The lowest energy conformations of 4a and 5a were located using Density Functional Theory (DFT) at the M06-2X/def2-TZVP level of theory. Two lowest energy conformations of 4a differ with respect to the position of the N atom …

Advanced Analytical Method Development: From Highly-Enrolled Classroom To Data-Intensive Proteomics, Laxmi Sinduri Vuppala

USF Tampa Graduate Theses and Dissertations

In analytical chemistry, method development is key to identifying, separating, and quantifying chemical components of interest systems. The chemical aspects are fundamental to understanding the subject of any analytical system, whether in academic research, industry, or government. These methodologies serve as a bridge between the classroom, where students are taught to be curious and enlightened, and research, where one strives to contribute. The Ph.D. dissertation integrates advanced methodologies in basic and applied research and advanced instrumentation, but the core criteria for validation remain the same. As part of chemical education curriculum development, a large cohort of undergraduates performed two gas …

Development Of 1,2-Cis-Selective Glycosylation Protocols And Multistep Synthesis Of Glycans From Acinetobacter Baumannii., Dancan Kamau Njeri

LSU Doctoral Dissertations

Access to various oligosaccharides has been made possible by glycosylation reactions. This is mainly through chemical synthesis and enzymatic approaches. Herein, I talk about glycosylation through chemical synthesis. In general, glycosylation reactions lead to a mixture of 1,2-cis and 1,2-trans stereoisomers. Stereoselective access to 1,2-trans isomer is highly developed; it efficiently relies on neighboring group participation. However, efficient access to 1,2-cis selective glycosylation is still a work in progress. In Chapter 1, I highlight notable efforts developed so far that address the 1,2-cis selectivity challenge in glycosylation.

In Chapter 2, I demonstrate how I improved …

Computational, Synthetic And Spectroscopic Studies On Donor Acceptor Transition Metal Complexes, Ranjana Dangi

Chemistry and Chemical Biology ETDs

Fundamental advances in our ability to design and construct electronic components at the nanoscale will require new design paradigms. One proposed nanoscale electronic component is the molecular rectifier. Molecular and molecule-based electronic components are advantageous due to their ease of synthetic manipulation, and the fact that the size dimensions of molecules are inherently at the nanoscale (0.5 - 3nm). Our group has shown how the Donor-Bridge-Acceptor biradical approach can be used to derive key structure-property relationships that allow insight into the choice of bridge fragments for molecular rectification by using constitutional isomers of the donor-bridge-acceptor biradical (NN-Th-Py-SQ) (S=1/2 ortho-semiquinonate, …