Chemistry Commons^™

Dark-Binding Process Relevant To Preventing Photosensitized Oxidation: Conformation-Dependent Light And Dark Mechanisms By A Dual-Functioning Diketone, Sarah J. Belh, Niluksha Walalawela, Stas Lekhtman, Alexander Greer

Publications and Research

Few photosensitizers function in both light and dark processes as they usually have no function when the lights are turned off. We hypothesized that light and dark mechanisms in an α-diketone will be decoupled by dihedral rotation in a conformation- dependent binding process. Successful decoupling of these two functions is now shown. Namely, anti- and syn-skewed conformations of 4,4′-dimethylbenzil promote photosensitized alkoxy radical production, whereas the syn conformation promotes a binding shutoff reaction with trimethyl phosphite. Less rotation of the diketone is better suited to the photosensitizing function since phosphite binding arises through the syn conformer of lower stability. The …

Performance Of Nitrogen As A Carrier Gas In Capillary Gas Chromatography Using A Thin Film Column, Brittany A. Handzo

Seton Hall University Dissertations and Theses (ETDs)

Gas chromatography (GC) is one of the most widely used analytical techniques for the separation and analysis of volatile compounds. Solids, liquids, and gases, organic and inorganic materials, and large molecular weight compounds can all be analyzed via this technique. Gas chromatographic separations are fast, accurate, and reliable. One of the reasons why these separations are so efficient is because of the carrier gas. The purpose of the carrier gas is to carry the injected sample through the column. It is known as the mobile phase and does not interact chemically with the sample. Common carrier gases include helium, hydrogen, …

Resin And Magnetic Nanoparticle-Based Free Radical Probes For Glycan Capture, Isolation, And Structural Characterization, Kimberly Fabijanczuk, Kaylee Gaspar, Nikunj Desai, Jungeun Lee, Daniel A. Thomas, J. L. Beauchamp, Jinshan Gao

Department of Chemistry and Biochemistry Faculty Scholarship and Creative Works

By combining the merits of solid supports and free radical activated glycan sequencing (FRAGS) reagents, we develop a multifunctional solid-supported free radical probe (SS-FRAGS) that enables glycan enrichment and characterization. SS-FRAGS comprises a solid support, free radical precursor, disulfide bond, pyridyl, and hydrazine moieties. Thio-activated resin and magnetic nanoparticles (MNPs) are chosen as the solid support to selectively capture free glycans via the hydrazine moiety, allowing for their enrichment and isolation. The disulfide bond acts as a temporary covalent linkage between the solid support and the captured glycan, allowing the release of glycans via the cleavage of the disulfide bond …

Low Temperature Liquid Metal Batteries For Energy Storage Applications, Cameron A. Lippert, Kunlei Liu, James Landon, Susan A. Odom, Nicolas E. Holubowitch

Center for Applied Energy Research Faculty Patents

The present invention relates to a molten metal battery of liquid bismuth and liquid tin electrodes and a eutectic electrolyte. The electrodes may be coaxial and coplanar. The eutectic electrolyte may be in contact with a surface of each electrode. The eutectic electrolyte may comprise ZnC1₂:KCI.

In‐Situ Extraction And Impregnation Of Black Walnut Husk Into Polyethylene Film Using Supercritical Carbon Dioxide With An Ethanol Modifier, Jonathan Wenzel, Veronica R. Moorman, Lihua Wang, Isaiah Spencer-Williams, Mitchell Hall, Cheryl Samaniego, Michelle Ammerman

Chemistry & Biochemistry Publications

Walnuts are commonly cultivated for their kernel, which is a rich source of antioxidant phenolic compounds. The husk likewise contains antioxidant and antimicrobial compounds, but is typically discarded without further processing. Antioxidant compounds are useful in creating active packaging films, but typically decompose at melt extrusion temperatures in polymer processing. Due to carbon dioxide's low critical point and ability to swell polymer films, supercritical carbon dioxide may be used to impregnate phenolic compounds into polymers. For this study, a novel technique is used to simultaneously produce walnut husk extracts and impregnate the extract into polymer films in the same batch …

“Treat Me Covalently” – New Tools To Improve Covalent Drug Design For Advancement Of Cancer Treatments, Yuliya Mazo

Student Theses and Dissertations

The goal of this project was to investigate the complex mechanism of covalent bonding among different molecules and their targets in a modeling software ICM-Pro. Specifically, it included the identification of fundamental aspects of a covalent bonding mechanism of the Michael addition reaction. Michael addition reaction of electrophilic α, β-unsaturated carbonyl compounds with a nucleophilic cysteine residue in thymidylate synthase, papain, and EGFR tyrosine kinase were examined. Thymidylate synthase and EGFR were chosen because they are important targets in the treatment of various types of cancer. In order to find the most optimal parameters, identification and assessment of the effect …

Two Algorithms For The Reorganisation Of The Problem List By Organ System, Daniel B. Hier, Joshua Pearson

Chemistry Faculty Research & Creative Works

Objective Long Problem Lists Can Be Challenging to Use. Reorganization of the Problem List by Organ System is a Strategy for Making Long Problem Lists More Manageable. Methods in a Small-Town Primary Care Setting, We Examined 4950 Unique Problem Lists over 5 Years (24 033 Total Problems and 2170 Unique Problems) from Our Electronic Health Record. All Problems Were Mapped to the International Classification of Diseases, 10th Revision, Clinical Modification (ICD-10-CM) and SNOMED CT Codes. We Developed Two Different Algorithms for Reorganizing the Problem List by Organ System based on Either the ICD-10-CM or the SNOMED CT Code. Results the …

Development And Application Of Mass Spectrometry-Based Protein Footprinting In Structural Proteomics, Ming Cheng

Arts & Sciences Graduate Student Theses and Dissertations

Integral mass spectrometry (MS) has emerged as an important tool for protein structural characterization. It readouts are a broad range of structural information, including stoichiometry, interactions, conformations and conformation change, and dynamics. Protein footprinting is a pivotal component in the intergral MS toolkit.My dissertation centers around the development and application of protein footprinting to characterize protein structure. It is divided into seven chapters.Chapter 1 serves as the introduction for integral mass spectrometry in structural proteomic.In Chapter 2, we extended the fast-photochemical oxidation of proteins (FPOP) platform by adding the trifluoromethyl radical (•CF3) as a new reagent. We discovered that •CF3 …

Sideromycin Pathway Elucidation: Insights Into Salmycin Biosynthesis, Transport Paradigms, And Drug Release, Gerry Sann Macaraeg Rivera

Arts & Sciences Graduate Student Theses and Dissertations

Antibiotic resistance is an increasing threat in today’s society. In order to overcome resistant bacteria, it is necessary to discover new drugs with novel mechanisms of action. This work focuses on the sideromycin pathway, encompassing the biosynthetic production, mechanism of entry and hydrolysis-mediated drug release. Sideromycins are an interesting approach to combat the rise of antibiotic resistance since they provide a different avenue that overcomes problems that arise when entering the cell. The dissertation is separated into distinct sections dealing with the various areas of interest in the sideromycin pathway, particularly for the sideromycin, salmycin, produced by Streptomyces violaceus. The …

Zirconium Tetrachloride, Fundamental Chemistry And Nuclear Fuel Cycle, Rosendo Borjas Nevarez

UNLV Theses, Dissertations, Professional Papers, and Capstones

Zirconium alloys are used in the United States as cladding materials in nuclear reactors. The purification of Zr is of relevance due to the large amount of spent nuclear fuel produced every year (2,000 metric tons per year and rising), of which 25% corresponds to radioactive zirconium cladding. Through the recovery and reuse of Zr, estimated savings of $40 million per year are estimated due to the high cost of hafnium-free nuclear grade zirconium, and also due to the minimization of nuclear waste disposal requirements.

Several chemical approaches have been proposed for the recovery and purification of Zr. Historically, a …

The Retrospective Analysis Of Radionuclides In Banded Coral From The Bikini Atoll, Athena Marie Gallardo

UNLV Theses, Dissertations, Professional Papers, and Capstones

Nuclear weapons testing conducted within the Bikini Atoll in the Marshall Islands resulted in local fallout contamination, including long lived isotopes of plutonium (Pu) and uranium (U), within the surrounding environment. The Bikini lagoon provides a continuous source of Pu (239+240Pu) and U (236U) to the Pacific Basin. The rate at which these isotopes are flushed from the lagoon to the ocean is balanced by inputs from remobilization of lagoon sediments. This research will provide a basis for predicting future change in the solubility and export potential of Pu and U in lagoon sediments. This is important to better understand …

Instrumentation For Dynamic Nuclear Polarization And Application Of Electron Decoupling For Electron Relaxation Measurement, Nicholas Howard Alaniva

Arts & Sciences Graduate Student Theses and Dissertations

Dynamic nuclear polarization nuclear magnetic resonance (DNP NMR) exploits internal electron spin and nuclear spin interactions to increase sensitivity and uncover valuable information regarding structure and dynamics of a system. To manipulate these interactions, instrumentation is developed to combine high-power microwave and radiofrequency irradiation with the ability to spin samples at the magic angle (MAS) at temperatures from 90 K to 4.2 K. Electron decoupling uses frequency-modulated microwaves to mitigate the electron-nuclear dipolar interaction, improving signal intensity and resolution in DNP NMR experiments. Electron decoupling is combined with short DNP periods to encode electron spin information in polarized nuclear signal. …

Devising A Scalable Synthesis To Probe The G-Protein Cell Receptor Signaling Pathway, Matthew Robert Medcalf

Arts & Sciences Graduate Student Theses and Dissertations

The G-protein coupled cell receptor signaling pathway is amongst the largest and most diverse class of cell-surface receptors in the body. Nearly 800 different genes encode for these cell membrane receptors which are responsible for mediating a variety of hormones, neurotransmitters, and sensory stimuli through the activation of intracellular G proteins. To date, roughly 34% of pharmaceuticals on the market target GPCR’s, but despite this fact, there are still many difficulties associated with targeting this family of receptors. The vast number of GPCR’s, disease states resulting from a dysregulation of multiple GPCR signaling pathways, and difficulties crystalizing and purifying the …

Influence Of Biosolids Upon The Uptake Of Mn And Cd By Radish (Raphanus Sativus L.), Oluwadamilola O. Fateru

Electronic Theses and Dissertations

The influence of biosolids upon the uptake of Mn and Cd by radish (Raphanus sativus L.) was investigated through the characterization of biosolids, sequential extraction of the biosolids, and the determination of the metal content in the root, shoot and leaves of radish (Raphanus sativus L.).The biosolid samples from Nacogdoches Wastewater Sludge (NWWS), Lufkin Wastewater Sludge (LWWS), Soil Therapy Compost (STC) had pHs between 5.33 – 6.74. The elemental compositions of the biosolid samples were determined using inductively coupled plasma optical emission spectroscopy (ICP-OES) and SEM/EDX. Major elements (K, Mg, Mn, P) needed for plant growth …

Design Of Efgr Kinase Domain Inhibitors For The Potential Treatment Of Lung And Other Cancers, Jodie Meng '20

Student Publications & Research

In 2018 alone, over 18 million cancer-related cases were diagnosed and 9.5 million cancer-related deaths occurred worldwide. As a small-molecule drug orally administered for the treatment of lung and pancreatic cancer, erlotinib (Tarceva®) inhibits the phosphorylation of the tyrosine kinase domain in the Epidermal Growth Factor Receptor (EGFR). Inhibition of EGFR reduces the bioactivity of tumor-associated endothelial cells and interferes with signal pathways involved in metastasis and development of angiogenesis. Increase in drug concentration leads to adverse effects, ranging from rash and nausea to gastrointestinal bleeding, perforation, hepatic failure, among others. Therefore, it is desirable to reduce the toxicity and …

Computer-Aided Drug Design For The Potential Treatment Against Mycobacterium Tuberculosis, Alyssa Daniels '20, Rebecca Ellington '19

Student Publications & Research

Tuberculosis (TB) is a disease that can infect any part of the body, but most often infects the lungs. About 9 million people are infected with TB each year, and left untreated, TB is deadly. However, even when treated, Mycobacterium Tuberculosis (MTB), the pathogenic bacteria responsible for TB, can become drug-resistant and patients will need a much more rigorous treatment. Isocitrate lyase (ICL) is an enzyme that allows tuberculosis (and other pathogens) to survive in the body. ICL is an enzyme in the glyoxylate cycle that catalyzes the cleavage of isocitrate to succinate and glyoxylate. MTB is facilitated by this …

C(Sp2)-C(Sp3) Cross-Coupling Of Aryl Halides And Active C(Spp3)-H Bonds Via Dual Catalysis: Organic Photocatalysis/Nickel Redox Catalysis, Nicholas Armada

Department of Chemistry: Dissertations, Theses, and Student Research

Convenient catalytic methodologies that can facilitate the formation of C-C bonds are undoubtedly of great interest in synthetic organic chemistry. Recent reports in literature have showcased hybrid catalytic methods that couple Ni-redox catalysis and photocatalysis to enable C-H activation of tetrahydrofuran (THF) and subsequent cross-coupling with aryl halides in appreciable yields and under relatively mild reaction conditions.^1-2 However, these studies used expensive, heavy metal-containing photocatalysts and both report difficulty obtaining low-specificity across their scopes of aryl-halides. The following report will shed light on a class of photo-excitable small organic molecules that – in conjunction with a catalytic Ni-redox cycle …

Influencing Factors On The Velocity And Temperature Of Propagating Fronts In Acrylate Composites, Samuel Morris Bynum

LSU Doctoral Dissertations

Thermal frontal polymerization is a type of polymerization in which a localized reaction zone propagates through an unstirred system. It is incumbent upon the production and transport of heat produced as a result of the exothermic reaction associated with free-radical polymerization. First discovered in the 1970s, frontal polymerization has been since utilized to produce a variety of different materials, utilizing a variety of different chemistries. The temperature of the propagating front and the velocity at which it propagates can be influenced via chemical or physical means. We show that through careful selection of monomers and control of the concentration of …

Building Mof Nanocomposites With Oxidized Graphitic Carbon Nitride Nanospheres: The Effect Of Framework Geometry On The Structural Heterogeneity, Dimitrios A. Giannakoudakis, Teresa J. Bandosz

Publications and Research

Composite of two MOFs, copper-based Cu-BTC (HKUST-1) and zirconium-based Zr-BDC (UiO-66), with oxidized graphitic carbon nitride nanospheres were synthesized. For comparison, pure MOFs were also obtained. The surface features were analyzed using x-ray diffraction (XRD), sorption of nitrogen, thermal analysis, and scanning electron microscopy (SEM). The incorporation of oxidized g-C3N4 to the Cu-BTC framework caused the formation of a heterogeneous material of a hierarchical pores structure, but a decreased surface area when compared to that of the parent MOF. In the case of UiO-66, functionalized nanospheres were acting as seeds around which the crystals grew. Even though the MOF phases …

Coordination Of Anions By Noncovalently Bonded Σ-Hole Ligands, Steve Scheiner, Mariusz Michalczyk, Wiktor Zierkiewicz

Chemistry and Biochemistry Faculty Publications

Research on σ-hole interactions that include halogen, chalcogen, pnicogen, and tetrel bonding has been accelerating in recent years. These cousins of the H-bond have many similar properties, including geometric preferences and energetics. Most of the work to date has focused on neutral complexes, with less known about these bonds to anions. This review summarizes the current state of knowledge about the complexes of anions with ligands that engage in these sorts of noncovalent bonds. Of particular interest are comparisons with H-bonds, and how the geometry of the fully coordinated complex varies as the number of surrounding ligands increases. A specific …

Oh Chemistry Of Non-Methane Organic Gases (Nmogs) Emitted From Laboratory And Ambient Biomass Burning Smoke: Evaluating The Influence Of Furans And Oxygenated Aromatics On Ozone And Secondary Nmog Formation, Matthew M. Coggon, Christopher Y. Lim, Abigail R. Koss, Kanako Sekimoto, Bin Yuan, Jessica B. Gilman, David H. Hagan, Vanessa Selimovic, Kyle J. Zarzana, Steven S. Brown, James M Roberts, Markus Müller, Robert Yokelson, Armin Wisthaler, Jordan E. Krechmer, Jose L. Jimenez, Christopher Cappa, Jesse H. Kroll, Joost De Gouw, Carsten Warneke

Chemistry and Biochemistry Faculty Publications

Chamber oxidation experiments conducted at the Fire Sciences Laboratory in 2016 are evaluated to identify important chemical processes contributing to the hydroxy radical (OH) chemistry of biomass burning non-methane organic gases (NMOGs). Based on the decay of primary carbon measured by proton transfer reaction time-of-flight mass spectrometry (PTR-ToF-MS), it is confirmed that furans and oxygenated aromatics are among the NMOGs emitted from western United States fuel types with the highest reactivities towards OH. The oxidation processes and formation of secondary NMOG masses measured by PTR-ToF-MS and iodide-clustering time-of-flight chemical ionization mass spectrometry (I-CIMS) is interpreted using a box model employing …

Zirconia-Based Compositions For Use In Passive NoX Adsorber Devices, Deborah Jayne Harris, David Alastair Scapens, John G. Darab, Mark Crocker, Yaying Ji

Chemistry Faculty Patents

A passive NO_x adsorbent includes: palladium, platinum or a mixture thereof and a mixed or composite oxide including the following elements in percentage by weight, expressed in terms of oxide: 10-90% by weight zirconium and 0.1-50% by weight of least one of the following: a transition metal or a lanthanide series element other than Ce.

Although the passive NO_x adsorbent can include Ce in an amount ranging from 0.1 to 20% by weight expressed in terms of oxide, advantages are obtained particularly in the case of low-Ce or a substantially Ce-free passive NO_x adsorbent.

Nanopatterned Silk Fibroin Films With High Transparency And High Haze For Optical Applications, Corey Malinowski, Fengjie He, Yihong Zhao, Ivan Chang, David W. Hatchett, Shengjie Zhai, Hui Zhao

Chemistry and Biochemistry Faculty Research

Simultaneous high transparency and high haze are necessary for high-efficiency optical, photonic, and optoelectronic applications. However, a typical highly transparent film lacks high optical haze or vice versa. Here, we report a silk fibroin-based optical film that exhibits both ultrahigh optical transparency... (See article for full abstract).

Total Phenolic And Flavonoid Contents Of Anacyclus Pyrethrum Link Plant Extracts And Their Antioxidant Activity, Hanane Elazzouzi, Nadia Zekri, Touriya Zair, Mohamed Alaoui El Belghiti

Karbala International Journal of Modern Science

In this study, Anacyclus pyrethrm Link (roots) is a medicinal plant from the Asteraceae family, endemic to Morocco and is widely used in traditional medicine; was investigated for their total phenolics, flavonoids contents and antioxidant activities. The quantitative estimation of total flavonoids and phenols by the colorimetric method showed that the extracts were prepared by fractionation of the crude hydromethanolic extract (ethyl acetate and n-butanol). The phenol content of various extracts, estimated by the Folin-Ciocalteu method, was between 1,44 and 12,82 mg EAG / g extract of A. pyrethrum. Moreover, it is clear that ethyl acetate was the …

Design Of Reinforced Concrete Deep Beams Using Particle Swarm Optimization Technique, Qais F. Hasan, Dler A. Al-Mamany, Omer K. Fayadh

Karbala International Journal of Modern Science

Researches available in literature interrelating neural networks to civil engineering design problems, especially for beep beams, are very rare. Therefore, an optimization algorithm is developed and verified in this study and coded using MATLAB functions to determine the optimum cost design of reinforced concrete deep beams. ACI 318-14 code method is used benefiting from iterative particle swarm optimization technique due to its efficiency and reliability. Minimizing total cost is used as the objective function in terms of four decision variables. Self-adaptive penalty function technique is used to handle constraints for each of the 300 randomly selected particles, and in each …

Artificial Bee Colony Algorithm For Solving Fuzzy Multi-Objective Bed Allocation Model, Abdulhakeem Luqman Hasan

Karbala International Journal of Modern Science

With the improvement of the medical services frameworks rivalry, hospitals face more and more challenges. In the interim, allotment of resource has a crucial influence on performing competitive benefits in a hospitals. To choose the suitable beds number is one of the most essential tasks in hospital administration. Anyway, in true condition, bed allotment choice is a multiple-side problem with weakness and haphazardness of the information available. It is so sophisticated. Therefore, the research about bed allotment difficulty is comparatively rare under considering multiple departments, nursing hours, and stochastic information about arrival and service of patients. In this paper, we …

Performance Study Of The Membrane Based Layered Double Hydroxides ‘Znal-Gh’ In The Purification Of Groundwater, Jaouad Zerhouni, Omar Qabaqous, Fouzia Rhazi Filali, Mohammed Naciri Bennani, Najib Tijani

Karbala International Journal of Modern Science

The objective of this work is focused on the preparation and characterization of plan microfiltration membrane Zn₃Al-Gh and the study of their efficiency in the treatment of ground water. This membrane was carried by using the support of the clay such as Ghassoul ‘Gh’ prepared by using dry uniaxial compaction method. The layered double hydroxides (LDH) based on Zn₃Al-CO₃with molar ratio (Zn²⁺/Al³⁺=3) was deposited on support by direct co-precipitation method.

The characterizations of the membrane LDH-Gh ‘Zn₃Al-Gh’ and deposited layer Zn₃Al-CO_3, was done by scanning …

Evaluation Of Atmospherically Gases Using Models Flaash And Quac To Hyper-Spectral Imagery, Asmaa Maher

Karbala International Journal of Modern Science

The important step is correction of the effect of atmospheric on hyper-spectral imagery of the VIS “visible”, short wave & NIR “near-infrared” spectral range. In general, the cause for limiting the use of hyperspectral images is the atmospheric effects, so, atmospheric correction is necessary for any accurate processing. In this work, two atmospheric correction techniques have been applied on Hyper-spectral image. From the raw original image and also from the FLAASH and QUAC atmospheric corrected images the spectra of vegetation, water and soil were extracted. The acquisition data for study contained Hyperion bands for year “2015” images over each of …

Editorial Board

Karbala International Journal of Modern Science

No abstract provided.

Semitransparent Sb2s3 Thin Film Solar Cells By Ultrasonic Spray Pyrolysis For Use In Solar Windows, Jako S. Eensalu, Atanas Katerski, Erki Kärber, Lothar Weinhardt, Monika Blum, Clemens Heske, Wanli Yang, Ilona Oja Acik, Malle Krunks

Chemistry and Biochemistry Faculty Research

The integration of photovoltaic (PV) solar energy in zero-energy buildings requires durable and efficient solar windows composed of lightweight and semitransparent thin film solar cells. Inorganic materials with a high optical absorption coefficient, such as Sb2S3 (>105 cm−1 at 450 nm), offer semitransparency, appreciable efficiency, and long-term durability at low cost. Oxide-free throughout the Sb2S3 layer thickness, as confirmed by combined studies of energy dispersive X-ray spectroscopy and synchrotron soft X-ray emission spectroscopy, semitransparent Sb2S3 thin films can be rapidly grown in air by the area-scalable ultrasonic spray pyrolysis method. Integrated into a ITO/TiO2/Sb2S3/P3HT/Au solar cell, a power conversion …