Physical Sciences and Mathematics Commons^™

The Investigation Of Singlet Fission From The Perspective Of Hierarchy Of Pure States (Hops), Tao (James) Chen

Chemistry Theses and Dissertations

This thesis provides a preliminary investigation of singlet fission from the perspective of Hierarchy of pure states (HOPS), which provides a numerical exact solution for the investigation of a series of open quantum systems. Since the inception of the concept of singlet fission about half a century ago, this photo-physical process has attracted the attention of a multitude of researchers and has been extensively studied theoretically and experimentally. However, these previous methods for the investigation of singlet fission focus more or less on tackling the underlying mechanisms of singlet fission from the perspective of perturbation. So far, the HOPS method …

Implementation And Assessment Of A Course-Based Undergraduate Research Experience (Cure) In General Chemistry, Alissa Potts

College of Science and Health Theses and Dissertations

Course-based undergraduate research experiences (CUREs) are growing in popularity in the chemistry community to replace traditional laboratory courses. This approach creates a research experience for a larger number of students than traditional research mentorship experiences offered at universities. CUREs can help students take ownership of projects, learn to design and troubleshoot experimental setups, problem-solve experiments that don’t have a “known answer”, and gain confidence in the laboratory. To assess the effectiveness of a general chemistry laboratory-based CURE course with DePaul students, the Experimental Design Ability Test (EDAT) and the Meaningful Learning in the Laboratory Instrument (MLLI) survey were given to …

A Computational Study Of Adsorptive Desulfurization In Metal Organic Frameworks, Kyle Concha

Theses

Fossil fuel usage has been related to several concerns about the environment and human health. One of these concerns is related to fuels containing Organic Sulfur Compounds (OSCs) which upon burning produce hazardous compounds such as SO₂ which contributes to acid rain and affects respiratory health. Removal of these OSCs is an important field of study as it can prevent the production of SO_x compounds. One technique to remove OSCs is Adsorptive Desulfurization (ADS) in which Metal Organic Frameworks (MOFs) are potential candidates to be used as adsorbents. Two archetypal MOFs, HKUST-1 and Cu₃HHTP₂, …

Cooking With Chemistry: Marshmallows, Admin Stem For Success

STEM for Success Showcase

This lesson plan teaches students thermodynamics, foam, and other chemistry topics by cooking marshmallows.

New Methods For Core-Hole Spectroscopy Based On Coupled Cluster Theory, Megan Simons

Chemistry Theses and Dissertations

X-ray absorption spectra (XAS) is a method used to investigate atomic local structure and electronic states. Coupled cluster method is a numerical method used for describing many-body systems and electron correlation in a wavefunction. When equation-of-motion coupled cluster is used in XAS calculations, the ground state is applied to the excitation operator, which excites or ionizes the electron. This causes a large orbital relaxation error, normally ~5 eV, which leads to the need for triple excitations in order to obtain accurate results.

This dissertation introduces a coupled cluster method that uses "transition potential" reference orbitals to reduce the orbital relaxation …

Celebrating Native Chemists And Encouraging More Native Talent In Stem, Lisa Villa

Staff publications

This editorial was written to accompany cover art submitted to the American Chemical Society's 2023 ACS Diversity & Inclusion Cover Art Series, and selected as the July cover for Environmental Science & Technology Letters. The artwork design features several prominent chemists who are also strong advocates for increasing the number of Native American/First Nation scientists. They recognize how cultural beliefs may often be in conflict with scientific conversations, but have been working to attract and encourage Native American talent in the STEM fields.

The published cover art is included as a supplemental file.

The Novel Chlorination Of Zirconium Metal And Its Application To A Recycling Protocol For Zircaloy Cladding From Spent Nuclear Fuel Rods, Breanna K. Vestal

Doctoral Dissertations

A novel protocol has been developed for the chemical removal of zirconium alloy (Zircaloy) cladding from spent nuclear fuel rods and subsequent isolation and purification of nuclear-grade zirconium chloride derived therefrom. This protocol is based on the chemistry developed from two new scientific findings.

First, two new oxidative chlorination reactions have been discovered for zirconium metal. In both solvents, zirconium can be quantitatively chlorinated at temperatures less than 150°C, with the operative equations seen below. In sulfur monochloride, the reaction is completed in 2 – 4 hours via surface etching, exhibiting 0^th order kinetic behavior. The elemental sulfur byproduct …

Quantitative Analysis Of The Proteomic Selectivity Of Acidic Reductive Alkylation Of Peptides, Connor Jewell

Honors Scholar Theses

Proteome quantification is a complicated process which takes on many methods, usually involving peptide derivatization and complex mass spectral analysis. Scores of techniques have been utilized to address issues of incomplete quantification. The implementation of IPTL labeling, or isobaric peptide terminal labeling, is a recent addition to the literature, which exploits the supposedly selective labeling of N-termini of tryptic peptides from the C-termini of lysine residues due to differences in basicity. This method has been shown to improve quantitation by reducing spectral complexity and provide more accurate and reproducible results on peptide abundance. Investigations into the selectivity of terminal derivatization …

Synthesis And Characterization Of Rhenium 2,2′-Pyridylnaphthyridine Metal Complexes, Benjamin F. Solomon

Honors Theses

Rhenium (Re) is a group 7 heavy 5d transition metal in the same family as manganese (Mn) and technetium (Tc). Re-carbonyl complexes are known to be catalysts for many different kinds of reactions from C-C bond formation to reduction reactions like CO₂ reduction (CO₂RR)^1,2. With this in mind, we have prepared a set of six Re-carbonyl complexes of 2,2′-pyridyl-1,6-naphthyridine (1,6- pynap) and 2,2′-pyridyl-1,8-naphthyridine (1,8-pynap), a redox non-innocent ligand containing a bpy moiety as well as an additional aryl nitrogen binding location at which another metal-ligand bond could form. We have synthesized these complexes as precursors …

Methods For Increasing The Electron Richness Of Iron Tricarbonyl Diimine Complexes, Francesca Lombardi, Joseph Maher, Sean Peloquin

Chemistry & Biochemistry Student Scholarship

Francesca Lombardi ’24, Major: Chemistry

Joseph Maher ’25, Major: Chemistry

Sean Peloquin ’26, Major: Biochemistry

Faculty Mentor: Dr. Maria Carroll, Chemistry and Biochemistry

The goal of our research is to synthesize new iron complexes that can reduce carbon dioxide. Increasing the electron richness of iron tricarbonyl diimine complexes, which have been synthesized previously in the Carroll research group, will increase the likelihood of a reaction with carbon dioxide occurring. We have taken two approaches to changing the electron density in the complexes. First, we reacted the complex Fe((CF3)2ArDABMe)(CO)¬3 with the reducing agent potassium on graphite, in order to reduce either …

Magnetic Slime, Admin Stem For Success

STEM for Success Showcase

Students learn chemistry and physics by making magnetic slime.

Invisible Ink, Admin Stem For Success

STEM for Success Showcase

Students create invisible ink to hide and reveal a message using chemistry.

Kinetic Analysis Of Glu115ala Cytosolic Human Malate Dehydrogenase Mutation Shows A Change In Activity On Non-Native Substrate Phenylpyruvate, Kailey Paar

Chemistry & Biochemistry Student Scholarship

The cytosolic human enzyme, malate dehydrogenase (MDH1), is believed to have a significant effect on the proliferation of cancerous cells. This enzyme oxidizes NADH to NAD+ as it converts oxaloacetate (OAA) to malate. This oxidation of NADH provides the needed NAD+ to cancer cells, which require NAD+ as they upregulate glycolysis in aerobic conditions. Targeting MDH1 can reveal new therapeutic treatments for cancer by preventing the conversion of OAA to malate and depleting NAD+ stores in cancer cells, which can be done by mutating residues in the enzyme and assessing the change in activity. Here we show the replacement of …

Sugar Water Density Activity, Admin Stem For Success

STEM for Success Showcase

In this activity students learn about density using sugar water. Attached is the activity's lesson plan and a teacher reflection on the activity.

Physical And Chemical Changes Lesson Plan, Admin Stem For Success

STEM for Success Showcase

Lesson plan and video for an activity on the difference between physical and chemical changes.

The Science Of Baking Bread, Admin Stem For Success

STEM for Success Showcase

Activity plan to teach biology and chemistry using a lesson on the baking of bread.

Microscale Chemical Manipulation And Imaging Using Photoactive Molecules And Light, Uroob Haris

Chemistry Theses and Dissertations

Chemical manipulation with light has been an active and growing area of research with important implications in materials science, biotechnology, and environmental science. From early investigations of light sensitive materials for photography in the 19^th century, to printing billions of transistors on a semiconductor chip in present day, scientists have gained a deep understanding of photochemistry and the processes that allow us to harness light for everyday applications. In this work, we explore microscale fabrication and molecular imaging using light and photoactive molecules as foundational tools. We develop a visible-light mediated technique for high resolution microscale chemical lithography comprising …

Exploring Protein Conformations And Functions Through Molecular Dynamics Simulations And Machine Learning, Hao Tian

Chemistry Theses and Dissertations

Proteins are essential biomacromolecules that perform a variety of critical functions in living organisms. The tertiary structure of a protein plays a crucial role in its biological activity as it determines how the protein interacts with other molecules. Consequently, understanding protein conformation and function is an important area of research with implications in medicine, biotechnology, and other fields.

The first part of this dissertation focuses on protein allostery, a process by which proteins transmit perturbations caused by binding at one site to a distal site, thereby regulating activity. With the development of computational methods like molecular dynamics simulations and machine …

Modeling Excited State Processes In Molecular Aggregates By Constructing An Adaptive Basis For The Hierarchy Of Pure States, Leonel Varvelo

Chemistry Theses and Dissertations

Simulating excitation energy transfer (EET) in molecular materials is of crucial importance for the development of and understanding of materials such as organic photovoltaics and photosynthetic systems and further development of novel materials. The Hierarchy of Pure States (HOPS) is an exact framework for the time evolution of an open quantum system in which a hierarchy of stochastic wave functions are propagated in time. The adaptive HOPS (adHOPS) method achieves size-invariant scaling with the number of simulated molecules for sufficiently large aggregates by using an adaptive basis that moves with the excitation through the material. To demonstrate the power of …

Damped Oscillating Phosphoryl Transfer Reaction In The Cyanobacterial Circadian Clock, Hye In Jang, Pyonghwa Kim, Yongick Kim

Chemistry Faculty Research

Most organisms have circadian clocks to ensure the metabolic cycle to resonate with the rhythmic environmental changes without “damping,” or losing robustness. Cyanobacteria is the oldest and simplest form of life that is known to harbor this biological intricacy. Its KaiABC-based central oscillator proteins can be reconstituted inside a test tube, and the post-translational modification cycle occurs with 24 h periodicity. KaiC’s two major phosphorylation sites, Ser-431 and Thr-432, become phosphorylated and dephosphorylated by interacting with KaiA and KaiB, respectively. Here, we mutate Thr-432 into Ser to find the oscillatory phosphoryl transfer reaction damps. Previously, this mutant KaiC was reported …

The Concentration Of Heavy Metals In Lincoln Nebraska's Tap Water, Evan Neuhaus

Honors Theses

Heavy metals are commonplace in nature, and are typically found in scarce quantities in all drinking sources. However, in high enough concentrations, they can have a myriad of negative health effects. This study seeks to find the concentrations of such metals in the Lincoln water supply utilizing the resources of the Water Center at the University of Nebraska at Lincoln. To test for discrete concentrations of trace elements, a method of using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) was implemented. ICP-MS uses plasma to ionize and atomize a sample which is then filtered into a series of cones into a …

Principles Of Chemistry-1, Rajnish Singh

KSU Distinguished Course Repository

Principles of Chemistry, chem 1211, is a 3 credit hour course, the first in a two-semester sequence covering the fundamental principles and applications of chemistry for science majors. Course content includes electronic structure of atoms and molecules, bonding fundamentals, fundamentals of chemical reactions, and gas laws. The course is taught asynchronously and the final exam being a national exam offered by the American chemical society, (ACS), that has to be taken in person.

Geothermal Energy And Its Impacts On The Environment, Aditi Gorthy, Nathan Tran, Laureen Pierre-Louis

Mako: NSU Undergraduate Student Journal

From the multitude of energy sources that we have developed throughout the eons, renewable energy or “clean energy” has been on the rise to combat global warming and climate change which burning nonrenewable sources of energy have contributed to. Before geothermal energy is used as part of the mainstream energy sources some aspects must be analyzed and resolved. Unfortunately, geothermal power plants still release pollutants, such as carbon dioxide and sulfur dioxide, into the environment and cause general environmental disruptions due to drilling and changes in land formations. Recent and future studies have been and should be conducted to find …

Data Set For "Atmospheric Aging Of Combustion-Derived Particles: Impact On Stable Free Radical Concentration And Its Ability To Produce Reactive Oxygen Species In Aqueous Media", Brian Majestic, Heather L. Runberg

Chemistry and Biochemistry: Data Sets

Environmentally persistent free radicals (EPFR) are an emerging pollutant found in soot particles. Understanding how these change as they move through the atmosphere is important to human health. Here, soot was generated in the laboratory and exposed to simulated sunlight. The concentrations and characteristics of EPFR in the soot was recorded. Additionally, formation of hydroxyl radical from the photoactivated soot was measured.

Lets Make Rock Candy!, Admin Stem For Success

STEM for Success Showcase

• Students should…

• be familiar with terms such as solubility, solute, solvent, and supersaturated solution.

• have a basic understanding of crystallization.

• understand the concept of delayed gratification and how they can practice this skill in their everyday lives to make smart financial decisions.

Green Synthesis Of Nanoparticles And Their Utilization In Electrochemical Detection Of Catechol- Or Phenol-Based Substances, Daniel Laurence Myers Iii

Browse all Theses and Dissertations

PART A: GREEN SYNTHESIS OF COPPER NANOPARTICLES AND THEIR UTILIZATION IN THE DETECTION OF NEUROTRANSMITTERS Neurotransmitters, such as dopamine and epinephrine, are chemicals frequently found in the brain and are responsible for a number of human moods, needs, and emotions.1, 2 Detection of such neurotransmitters allows for a better judgement of a person’s physical and mental state, a utility that is vital in determining the presence of disease and mental illnesses.2 Electrochemical detectors used for such detections are often modified by materials such as metal nanoparticles.3 However, synthesizing nanoparticles can involve or produce chemicals, ammonium hydroxide among them, that are …

Novel Technique In Production Of Pb (Ii)- Imprinted Polymers, Ehab Mohammed, Mostafa M. Elsheikh, Adham A. El-Zomrawy, Farag A. Ahmed

Al-Azhar Bulletin of Science

Ion imprinting techniques were used to produce ion imprinted polymer (IIP) particles for the selective removal of Pb2+ from aqueous environments. As the Templating monomers, acrylic acid, acrylic amine ligand, and Methylene Bisacrylamide crosslinker were chosen. The imprinted polymer was prepared by free radical polymerization. By leaching with 0.1 M HCl, the (Pb2+) ion was removed from the template. The polymer particles were characterized by IR spectroscopy, Thermal analysis and potentiometric analysis. The produced polymer was mechanically crushed into fine particles, assembled into a sensor probe, and linked to a bare HB graphite pencil electrode (GPE). The sensor has a …

Enhanced Adsorption Of Anionic Dyes Using Sr-Doped Zno Nanoparticles: Nonlinear Kinetics And Isotherm Studies, Mostafa H. Mohamed, Taha M. Elmorsi, H. M. Abdelbary

Al-Azhar Bulletin of Science

Using a co-precipitation process, sr-doped ZnO was prepared and demonstrated to be effective in the removal of anionic congo red dye, since its surface positive charge was increased to 17.3 mV. To investigate the surface morphology and physicochemical characteristics of Sr-doped ZnO, FTIR spectroscopy, scanning electron microscopy (SEM), elemental analysis, and point of zero charges (pHPZC) were employed. We conducted batch adsorption experiments to investigate the effects of contact time (180 minutes), pH (3.5–11), adsorbent dosage (0.5–3.0 g L−1), and temperature (288–328 K). The kinetic study was modeled using several equations, including pseudo-firstorder (PFO), pseudo-second-order (PSO), Elovich, and intra-particle diffusion …

Reduced Metal Nanocatalysts For Selective Electrochemical Hydrogenation Of Biomass-Derived 5-(Hydroxymethyl)Furfural To 2, 5-Bis(Hydroxymethyl)Furan In Ambient Conditions, Baleeswaraiah Muchharla, Moumita Dikshit, Ujjwal Pokharel, Ravindranath Garimella, Adetayo Adedeji, Kapil Kumar, Wei Cao, Hani Elsayed-Ali, Kishor Kumar Sadasivuni, Naif Abdullah Al-Dhabi, Sandeep Kumar, Bijandra Kumar

Chemistry & Biochemistry Faculty Publications

Selective electrochemical hydrogenation (ECH) of biomass-derived unsaturated organic molecules has enormous potential for sustainable chemical production. However, an efficient catalyst is essential to perform an ECH reaction consisting of superior product selectivity and a higher conversion rate. Here, we examined the ECH performance of reduced metal nanostructures i.e., reduced Ag (rAg) and reduced copper (rCu) prepared via electrochemical or thermal oxidation and electrochemical reduction process, respectively. Surface morphological analysis suggests formation of nanocoral and entangled nanowire structure formation for rAg and rCu catalysts. rCu exhibits slight enhancement in ECH reaction performance in comparison to the pristine Cu. However, the rAg …

Synthesis Of New Ligand-Based Phosphazo Ring And Its Transition Metal Complexes As Cancer Inhibitor: Spectroscopic, Dft, Antimicrobial, And Molecular Docking Investigations, Asmaa A. Hamed, Ahmed A. El-Sherif, Carmen M. Sharaby, Yousry A. Ammar, Mona F. Amine

Al-Azhar Bulletin of Science

A condensation between 2-sulfanilamidopyrimidine and a p-toluidine dimer of cyclodiazadiphosphetidine resulted in the formation of a new ligand, 2,2,4,4-tetrachloro-1,3-di-[p-tolyl]-2,4-di-[N-(pyrimidin-2-yl) benzenesulfonamide]-1,3,2,4-diazadiphosphetidine, (H2L). We investigated the chemical behavior of the newly prepared ligand was investigated by treating it with some chosen metal ions at a stoichiometric ratio of 1:2 (L:M), where M = Fe(III), Fe(II), Cu(II), Zn(II), Cd(II), and Ag(I), to provide colored complexes with accepted yields. Then, we characterized the ligand and related complexes using spectroscopic and analytical techniques. Investigations revealed that the geometrical structure of the complexes was octahedral, except for the silver complex was tetrahedral. From the spectral analyses, …