Chemistry Commons^™

Ultraviolet-Initiated In-Situ Cross-Linking Of Multifunctional Binder Backbones Enables Robust Lithium-Sulfur Batteries, Sha Li, Xiao Zhan, Gu-Lian Wang, Hui-Qun Wang, Wei-Ming Xiong, Li Zhang

Journal of Electrochemistry

Lithium-sulfur (Li-S) batteries show attractive prospects owing to their high theoretical energy density, but their commercialization still faces such challenges as lithium polysulfides shuttling, severe volume change and considerable polarization. These stubborn issues place higher demands on each component in the battery, such as the development of multifunctional binders with superior mechanical properties. Herein, ethoxylated trimethylolpropane triacrylate was firstly introduced into sulfur cathodes, and in-situ cross-linked by ultraviolet (UV) curing combined with traditional polyvinylidene difluoride binder (i.e., forming a binary binder, denoted as c-ETPTA/PVDF) to construct high-loading and durable Li-S batteries. The covalently cross-linked ETPTA framework not only significantly enhances …

Preface To The Special Issue On Lithium-Sulfur Batteries, Jia-Jia Chen, Ren-Jie Chen, Zhong Jin

Journal of Electrochemistry

No abstract provided.

Synthesis Of 2-Bromo-6-Alkylaminopyridines, 2,6-Dialkylaminopyridines, And Tren Based Ligands, Stephanie E. Carter

Honors College Theses

Extended metal atom chains (EMAC) are multimetallic complexes that feature a linear metal chain with metal-metal bonds surrounded by stabilizing ligand molecules. When EMACs are formed with paramagnetic metal ions, unique magnetic properties can be derived from direct metal to metal communication. The challenge is that EMAC complexes are challenging to synthesize due to the inherent weakness of most M-M bonds and the specificity of the ligands required to stabilize EMACs. In prior work by the Guillet group, the silyl aminopyridine (SAP) ligands were observed to stabilize very unique triiron complexes, but they were inherently unstable. In other work, scaffolded …

Cobalt/Carbon Composites As Sulfur Hosts For High-Performance Lithium-Sulfur Batteries, Yun-Rui Yang, Huan-Huan Dong, Zhi-Qiang Hao, Xiang-Xi He, Zhuo Yang, Lin Li, Shu-Lei Chou

Journal of Electrochemistry

Lithium-sulfur (Li-S) battery is one of the promising energy storage devices because of its high energy density. However, the sulfur cathode suffers from sluggish electrochemical reaction kinetics, slow charge transfer, large volume expansion and severe shuttle effect of lithium polysulfides inevitably resulting in low reversible capacity, poor rate performance and short cycle life, limiting its practical applications. Herein, the recent progress of cobalt/carbon composites, including cobalt nanoparticles and cobalt single atoms, as the sulfur host materials in Li-S batteries is overviewed. In general, cobalt plays the role of electrocatalyst, which inhibits the shuttle effect of lithium polysulfides, accelerates the electrochemical …

Recent Advances Of Functional Electrolyte Additives For Lithium-Sulfur Batteries, Xiu-Qing Zhang, Shuai Tang, Yong-Zhu Fu

Journal of Electrochemistry

Lithium-sulfur (Li-S) batteries have become one of the most promising next-generation battery systems due to their high energy density and low cost. However, the application of Li-S batteries still faces critical challenges, such as the low conductivities of S and Li₂S, shuttle effect of polysulfides and dendrite growth of Li, etc. The optimization of the electrolyte can ameliorate the electrolyte|electrode interphase, conveniently regulating the parasitic reaction and improving the performance of the resultant batteries. The functional additives in electrolytes provide chances to tune the interphase and even the redox mechanism to improve the performance of the batteries. In …

Metals And Alloys As Catalytic Hosts Of Sulfur Cathode For Lithium-Sulfur Batteries, Zhen-Yu Wang, Xue-Ping Gao

Journal of Electrochemistry

Lithium-sulfur batteries are recognized as one of the most promising next-generation energy storage devices, owing to the high theoretical energy density of 2600 Wh·kg^–1. However, their application has been seriously hindered by the sluggish electrochemical reaction kinetics of elemental sulfur and discharged products (Li₂S₂/Li₂S), and the notorious “shuttle effect” of soluble intermediate lithium polysulfide species, leading to poor cycle stability, low sulfur utilization and inferior coulombic efficiency. Introducing catalytic hosts into sulfur cathode is an efficient path to propel the conversion of sulfur-contained species, thus preventing the dissolution and loss of active-sulfur …

Brown Carbon From Photo-Oxidation Of Glyoxal And So2 In Aqueous Aerosol, David O. De Haan, Lelia N. Hawkins, Praveen D. Wickremasinghe, Alyssa D. Andretta, Juliette R. Dignum, Audrey C. De Haan, Hannah G. Welsh, Elyse A. Pennington, Tianqu Cui, Jason D. Surratt, Mathieu Cazaunau, Edouard Pangui, Jean-François Doussin

Chemistry and Biochemistry: Faculty Scholarship

Aqueous-phase dark reactions during the co-oxidation of glyoxal and S(IV) were recently identified as a potential source of brown carbon (BrC). Here, we explore the effects of sunlight and oxidants on aqueous solutions of glyoxal and S(IV), and on aqueous aerosol exposed to glyoxal and SO₂. We find that BrC is able to form in sunlit, bulk-phase, sulfite-containing solutions, albeit more slowly than in the dark. In more atmospherically relevant chamber experiments where suspended aqueous aerosol particles are exposed to gas-phase glyoxal and SO₂, the formation of detectable amounts of BrC requires an OH radical source …

Synthesis And Evaluation Of 1-Substituted Imidazo[4,5-C] Quinoline Tlr7 Agonists With Improved Potency, Emma Grace Deyoung

Undergraduate Honors Theses

TLR7 agonists are small molecules that are useful within cancer immunotherapy due to their ability to stimulate the TLR7 pathway resulting in NFκB activation, and cytokine release.1 Due to the risk of toxicity when delivered systemically, our team has employed a particular type of drug-delivery technology, Antibody Drug Conjugates (ADCs) to deliver these payloads directly to tumor tissue. The initial focus of this work was on E104 (8a), an imidazoquinoline TLR7 agonist, which was synthesized by the Tumey lab.1 However, the agonist was not sufficiently potent for many of the proposed applications of this technology, prompting a need to develop …

The Role Of Sars-Cov-2 Orf8 Protein Arks Motif On Novobiocin Binding, Si Chun Chiu, My T. Nguyen

Celebrating Scholarship and Creativity Day (2018-)

The discovery of the SARS-CoV-2 virus during the COVID-19 pandemic required scientists to develop medical solutions to reduce infectivity, severity of symptoms, and death. Although vaccines and drugs provided urgent assistance, the need to continue developing better drugs is necessary long term, and understanding the structure of the virus and finding potential inhibitors would prove vital to discovering solutions to this worldwide health problem. This experimental project focuses on targeting the unique accessory protein, Open Reading Frame 8 (ORF8) in SARS-CoV-2 through studying its interactions with a repurposable drug, novobiocin. Importantly, ORF8 specializes in helping evade immune system checks by …

Protein Engineering Of A Fluorescent Watermelon Malate Dehydrogenase, William Yu

Celebrating Scholarship and Creativity Day (2018-)

Malate dehydrogenase (MDH) is an enzyme that is prevalent in many metabolic processes, such as the Krebs cycle and the citric acid cycle4. It reversibly forms oxaloacetate and NADH from (S)-malate and NAD+,1. Tryptophan fluorescence would be ideal to monitor conformational changes of MDH, but watermelon glycosomal MDH does not contain any tryptophan amino acids4. The research question being tested here is whether or not it is possible to mutate MDH to contain a tryptophan while still retaining native-like specific activity. This research question has not been addressed as a literature search has shown no research has been done to …

Chemically Responsive Hydrogels, Properties, Pharmaceuticals, And Agricultural Applications: A Review, Mohammad Alrbaihat, Qusay Abu-Afifeh, Firas Al-Zeidaneen

Al-Bahir

A review of the literature on chemically responsive hydrogels about the selection of selectivity based on classification, properties, and application is presented in this article. Chemically responsive hydrogels are a type of hydrogel that undergo changes in their properties in response to specific stimuli. These hydrogels have attracted significant attention due to their potential applications in various fields, including pharmaceuticals and agriculture. Chemically crosslinked hydrogels are synthesized by covalent crosslinking of end-functionalized macromeres. Currently, a great deal of research is being conducted on hydrogel networks, also known as smart networks or hungry networks. This is owing to their potential use …

195 - Targeting Telomeric And C-Myc G4 Dna As An Anticancer Approach, Alexander Michaels, Sameela Haidari, Courtney Fetzer

GREAT Day Posters

G-quadruplex (G4) DNA are non-canonical higher order DNA structures formed from guanine rich sequences, made up of stacked G-tetrads stabilized by non-Watson-Crick (Hoogsteen) base pairing and K⁺ ions. Early interests in G4 DNA were spurred on by the revelation that G4 was formed in telomeric DNA sequences at the end of our chromosomes. This was particularly promising given that G4 structures formed in telomeric DNA were also found to inhibit an enzyme known as telomerase, which is overexpressed (>90%) in cancer cells. Cancer cells require telomerase activity for survival and "immortality", therefore stabilization of telomeric G4 can inhibit …

219 - Developing A Portable System Of Environmental Dna (Edna) Surveillance To Monitor Fish Population Dynamics And Detect Invasive Species In Conesus Lake And The Philippine Seas, Karina Mirza, Micah Ford, Morgan Comstock

GREAT Day Posters

Climate change is an increasing threat to many ecosystems worldwide. Due to global warming, many species are under threat of extinction while others are forced into unusual patterns of migration. In the Philippines, the fish Round Scad is a cheap source of protein in the diet of common citizens. Alarmingly, it is rapidly declining in both population and body size. In this project, we aim to develop a cheap, rapid, and sensitive method of monitoring the population dynamics of this fish in the wild. Recently, a new method called environmental DNA (eDNA) metabarcoding has been developed as a cost-effective way …

Probing The Effect Of Nitrogen And Boron Doping On Structures, Properties, And Stability Of C20 Clusters, Ramsay Revennaugh, Martina Kaledin

Symposium of Student Scholars

Fullerenes are carbon molecules arranged in a closed hollow shell to form spherical-like structures. These clusters exist in various sizes, C_n, with the smallest being C₂₀. C₂₀, often when doped with other elements, has shown promise in creating new materials as a catalyst and as energy storage material. Here, we look at the existence of C₂₀ doped with nitrogen or boron atoms using density functional theory (DFT). C₂₀ is doped with one to three boron or nitrogen atoms, respectively, including the five different C₁₈N₂ / C₁₈B_{2 …}

Ab Initio Calculations Of Vibrational Spectra Of Model Peptides, Katheryn Foust, Martina Kaledin

Symposium of Student Scholars

The function of biological molecules is closely related to their spatial structure and conformational dynamics. Therefore, understanding the structure and functions of small peptides contributes to gaining insight into the behavior of more complex systems. The peptide bond (-CO-NH-) is among the very important binding patterns in biochemistry. It links amino acids together, specifies rigidity to the protein backbone, and includes the two essential docking sites for hydrogen-bond-mediated protein folding and protein aggregation, namely, the C=O acceptor and the N-H donor parts. Therefore, the C=O (amide-I) and N-H (amide-A) vibrations provide sensitive and widely used probes into the structure of …

A Comparative Study Of Specific Enthalpy Of Aromatic Hydrocarbons With Simple Carbohydrates, Kohl D. Kervin, Subha Pratihar

ATU Scholars Symposium

Calorimetry is an aspect of chemistry primarily focused on determining the enthalpy of reactions (∆Hrxn). In the bomb calorimetry technique, the heat of combustion of chemical compounds can be measured experimentally. From this data and the application of Hess’s Law, ∆the Hrxn of several chemical reactions can be determined. The technique of bomb calorimetry can be applied to food, fuels, pharmaceuticals, and many other fields. The objective of the present project is to determine the specific enthalpy of various simple carbohydrates (naturally occurring sugars) through bomb calorimetry and compare it with that of aromatic hydrocarbons.

By performing benzoic acid standardization …

Chemical And Biological Investigation Of Sambucus Canadensis And Salvia Officinalis, Elizabeth Martin, Harley Hines, Amber Parnell

ATU Scholars Symposium

New treatments for cancer and bacterial infections are needed, especially because most patients acquire resistance to conventional first-line treatments. Many natural product metabolites exhibit potent activity. Sambucus sp.,elderberry, and Salvia sp., or sage, are well-known shrubs for their therapeutic benefits. This study aims to analyze how secondary metabolites are extracted from the Native American Elderberry, Sambucus canadensis, and Sage, Salvia officinalis. It also aims to investigate the process of vinegar baking of medicinal plants to enhance the chemical space and increase the biological properties. Vinegar-baked and non-vinegar-baked elderberries and sage were utilized to test this theory. A Soxhlet …

Bis(Difluoroborylamidinates) With Flexible Ethylene Bridges As Bifunctional Aggregation-Induced Emitters, Connor Welch

Symposium of Student Scholars

4,4-Difluoro-4-bora-3a,4a-diaza-s-indacenes (BODIPYs) represent one of the most prominent classes of dyes, since they are ubiquitously used in protein and DNA labelling, photodynamic therapies, as luminescent tags, sensors, laser dyes, paint and ink compositions, as well as for electroluminescent devices. [1] This is because of their robustness in terms of photochemical stability, polarity and pH changes of their environment, in particular under physiological conditions. The versatility to introduce multiple functional substituents and ability of BODIPYs to strongly absorb UV-light while providing sharp fluorescence peaks, combined with high quantum yields make these dyes highly attractive for numerous applications. Closely related azaBODIPYs offer …

Actualistic Testing Of The Influence Of Groundwater Chemistry On Degradation Of Collagen I In Bone, Paul Ullmann, Kristyn K. Voegele, Kenneth Lacovara

School of Earth & Environment Departmental Research

Recent experiments have heightened our understanding of reactions which can stabilize biomolecules during early diagenesis, yet little remains known about how groundwater chemistry can aid or hinder molecular preservation within a bone through geologic time. To elucidate this issue, we conducted actualistic experiments of bone decay employing varied fluid compositions to simulate a suite of groundwaters. Modern domestic chicken (Gallus gallus) femora were placed in a matrix of compositionally- and texturally-mature, fluvially-deposited sand. To simulate groundwater flow, deionized water or solutions enriched in calcium carbonate, phosphate, or iron were percolated through separate trials for a period of 90 days. After …

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 …

Toward The Design, Synthesis, And Characterization Of Abiotic Coiled-Coil Peptides Via Solid-Phase Copper-Catalyzed Azide-Alkyne Cycloaddition (Sp-Cuaac) Click Reaction For The Preparation Of Controlled Self-Assembly Molecular Building Block, Liaquat Ali

Chemistry Theses

The production of cutting-edge materials, the development of novel medications, drug delivery systems, technological advancements, and biosynthesizing all depend on molecular building blocks. Proteins are required for the creation of intricate, well-organized structures, and coiled-coil protein domains are vital subunits for the oligomerization of protein complexes, gene expression, and the structural components of biological materials. The numerous interactions between a wide variety of amino acids make it difficult to assemble protein complexes with a particular shape. In the current study, we successfully designed and synthesized four different 32-residue peptides, each of which had two modified amino azide residues. These peptides …

Surface Characterization Of Mixed-Mode Adsorbents Using Bet C-Constant Energy Scale, Dinah C. Lee

Seton Hall University Dissertations and Theses (ETDs)

Mixed-mode chromatography is a chromatographic method in which solutes interact with stationary phase through more than one interaction mode or mechanism. It is because of these multiple complex interactions, which makes it difficult to predict chromatographic behavior of analytes on Mixed-mode columns. In order to fully understand the retention mechanisms on Mixed-mode columns, the packing material properties must be well characterized since each characteristic may contribute to the overall chromatographic performance of the column. Many non-chromatographic and chromatographic techniques are available to characterize and compare Mixed-mode columns in terms of their interaction abilities, retentivity, surface chemistry, chemical properties and geometry. …

Ultrafast Dynamics Of Photosynthetic Light Harvesting: Strategies For Acclimation Across Organisms, Olivia C. Fiebig, Dvir Harris, Dihao Wang, Madeline P. Hoffmann, Gabriela S. Schlau-Cohen

Chemistry: Faculty Publications

Photosynthetic light harvesting exhibits near-unity quantum efficiency. The high efficiency is achieved through a series of energy and charge transfer steps within a network of pigment-containing proteins. Remarkably, high efficiency is conserved across many organisms despite differences in the protein structures and organization that allow each organism to respond to its own biological niche and the stressors within. In this review, we highlight recent progress toward understanding how organisms maintain optimal light-harvesting ability by acclimating to their environment. First, we review the building blocks of photosynthetic light harvesting, energy transfer, and time-resolved spectroscopic techniques. Then, we explore how three classes …

Transannular Functionalization Of Multiple C(Sp3)-H Bonds Of Tropane Via An Alkene-Bridged Palladium(I) Dimer, Ellen Y. Aguilera, En Chih Liu, Scott M. Thullen, Melanie S. Sanford

Chemistry Faculty Research & Creative Works

This Communication describes the Pd-catalyzed C(sp³)-H functionalization of a tropane derivative to generate products with functionalization at two (β/γ) or three (β/γ/β) different sites on the alicyclic amine core. These reactions proceed via an initial dehydrogenation to generate an alkene product that can react further to form a Pd(I) alkene-bridged dimer. Functionalization of this dimer affords β/γ/β-functionalized allylic arylation and allylic acetoxylation products.

The Influence Of Diamine Curing Additives On The Network Architecture Of Phthalonitrile Thermosetting Polymers, Tyler J. Richardson

Dissertations

Phthalonitrile monomers undergo diamine-promoted polymerization by a complex reaction mechanism involving two competitive cure pathways, forming two primary network architectures: linear polyisoindoline chains and branched triazine crosslinks. The influence of the diamine curing additive on the polymerization pathway, and the influence of the resulting network architectures on cured network properties, have not been adequately explored within the phthalonitrile field. Two structurally different diamine curing additives, bis[4-(3-aminophenoxy)phenyl] sulfone (mBAPS) and 1,3-phenylenebis((4-(4-aminophenoxy)phenyl)methanone) (AEK-134), were studied for the polymerization of resorcinol phenylphosphate phthalonitrile (RPPhPN), where the influence of diamine structure and concentration on the polymerization behavior, network architecture, and bulk thermal and thermomechanical …

Characterization Of Shinella 6-Hydroxy-(L)-Nicotine Oxidase (6hlno-Se), Kaitrin Funckes

Honors Theses

6-hydroxy-(L)-nicotine oxidase, isolated from the organism Shinella sp. HZN7 (6HLNO-SE), is an enzyme that during the catabolism of nicotine catalyzes the oxidation of (S)-6-hydroxynicotine to 6-hydroxypseudeooxynicotine. This enzyme is a member of the monoamine oxidase (MAO) structural family of flavoproteins, which contain a highly conserved FAD-binding domain. Within the binding domain is a conserved lysine residue that can be traced throughout evolutionary history in this family. 6HLNO isolated from Arthrobacter nicotinovorans serves as a model enzyme for the one isolated from Shinella as both catalyze the same reaction in this biochemical pathway and much has been studied about the Arthrobacter …

Synthesis And Characterization Of Some Disubstituted Cyclopentadienyl Rhenium Complexes As Potential Candidates In Semiconductive Materials, Chloe Vernon

Liberty University Research Week

Undergraduate

Three Minute Thesis

Thp-1 Monocytes As A Model For The Characterization Of Potential Agents For Hypersensitization Observed In Ags?, Colin Baker

Liberty University Research Week

Undergraduate

Three Minute Thesis

Incorporation Of Thiophenes And Benzothiophenes Into Novel Pi-Extended Dibenzophosphole Systems, Joshua Kim, Conner Schell

Campus Research Month

Dibenzophospholes are molecules with extended pi conjugation. This project aims to incorporate thiophenes and benzothiophenes into dibenzophosphole systems by using 2-bromothiophene, 2-bromobenzothiophene, and 3-bromobenzothiophene as starting materials. An ethyne intermediate is created via the Sonagashira reaction, which is further reacted to form the novel dibenzophosphole system. The ultimate goal is to fuse the newly incorporated functional groups, creating an even greater degree of conjugation.

Computational Study Of The Rotational Barrier In Indole Derivatives, Javaughn Martinez

Honors Theses

The purpose of this computational study is to understand the rotational barrier in indole derivatives, leading to stereoisomers, specifically atropisomers, which will impact the research direction focused on the development of a porphyrin hosts in Professor Starnes’s group. The Starnes research group is working to synthesize a porphyrin host that can function as a sensor or to remove harmful and deleterious anions such as phosphate and nitrates (Busschaert, et al, 2015). We will utilize the data provided to understand the required energy to restrict a rotation around the indole-benzene bond. To do so, the indole derivatives will be studied using …