Physical Sciences and Mathematics Commons^™

Orbital Analysis Of Bonding In Diarylhalonium Salts And Relevance To Periodic Trends In Structure And Reactivity, Shubhendu S. Karandikar, Avik Bhattacharjee, Bryan Metze, Nicole Javaly, Edward J. Valente, Theresa M. Mccormick, David R. Stuart

Chemistry Faculty Publications and Presentations

Diarylhalonium compounds provide new opportunities as reagents and catalysts in the field of organic synthesis. The three center, four electron (3c–4e) bond is a center piece of their reactivity, but structural variation among the diarylhaloniums, and in comparison with other λ3-iodanes, indicates that the model needs refinement for broader applicability. We use a combination of Density Functional Theory (DFT), Natural Bond Orbital (NBO) Theory, and X-ray structure data to correlate bonding and structure for a λ3-iodane and a series of diarylchloronium, bromonium, and iodonium salts, and their isoelectronic diarylchalcogen counterparts. This analysis reveals that the s-orbital on the central halogen …

Optimization Of Paper-Based Substrates For Surface Enhanced Raman Spectroscopic Biosensor Development, Kaylee M. Cappuccio

Undergraduate Honors Theses

Advancements in the field of analytical chemistry have greatly expanded the development of biosensors for the detection of a wide array of diseases. This study aims to optimize an affordable paper-based nanocomposite biosensor that utilizes surface-enhanced Raman spectroscopy (SERS). Specifically, it investigates the preparation parameters for a paper-based SERS substrate, including nanoparticle administration and drying procedures. A particular focus of this work is to assess how the wax-defined paper channels can effectively enhance SERS intensity. The results revealed that while the wax-printed wells can define the nanoparticle administration for SERS detection, wax backing may reduce the sensitivity of SERS by …

Multifunctional Carbon-Supported Cobalt-Nickel Compounds For Water Splitting And Energy Storage Applications, Wang Lin

Electronic Theses & Dissertations

In order to effectively reduce carbon emission and achieve the goal of mitigating climate change, hydrogen energy has high hopes as a representative of green energy. According to the most current and updated research, compounds of cobalt and nickel have been widely studied as alternatives instead noble metal materials as catalysts for the electrolysis of water. Based on some other research reports, a hydrothermal method to grow cobalt-nickel hydroxide on nickel foam that has been carbonized in advance was proposed. To compare the modification results of these materials by different activation methods, calcination, sulfidation, and phosphating were performed on the …

Biophysical Insight Into The Sars-Cov2 Spike–Ace2 Interaction And Its Modulation By Hepcidin Through A Multifaceted Computational Approach, Hamid Hadi-Alijanvand, Luisa Di Paola, Guang Hu, David M. Leitner, Gennady M. Verkhivker, Peixin Sun, Humanath Poudel, Alessandro Giuliani

Mathematics, Physics, and Computer Science Faculty Articles and Research

At the center of the SARS-CoV2 infection, the spike protein and its interaction with the human receptor ACE2 play a central role in the molecular machinery of SARS-CoV2 infection of human cells. Vaccine therapies are a valuable barrier to the worst effects of the virus and to its diffusion, but the need of purposed drugs is emerging as a core target of the fight against COVID19. In this respect, the repurposing of drugs has already led to discovery of drugs thought to reduce the effects of the cytokine storm, but still a drug targeting the spike protein, in the infection …

Influence Of Citrate And Phosphate On The Adsorption Of Adenosine-5′-Monophosphate At The Hematite Water Interface, Sudipta Rakshit, Avedananda Ray, Ali Taheri, Michael E. Essington

Agricultural and Environmental Sciences Faculty Research

Nucleic acid derived organic phosphorus (Po) is an important source of plant available P when degraded to inorganic phosphate (P(V)i). It is known that when nucleic acids or components are adsorbed on mineral surfaces, the enzymatic degradation is hindered or delayed. Thus, understanding adsorption/desorption mechanisms of nucleic acids and their derivatives are key to assess the biogeochemical pathways of Po cycling. Here we report adsorption mechanisms of adenosine-5′-monophosphate (AMP) on hematite, a common iron oxide mineral, under various solution properties using macroscopic and in situ attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopic probes. The effects of citrate, mimicking organic …

The Scientific Method As A Scaffold To Enhance Communication Skills In Chemistry, Thomas D. Montgomery, Joanne Rae Buchbinder, Ellen S. Gawalt, Robbie J. Iuliucci, Andrew S. Koch, Evangelia Kotsikorou, Patrick E. Lackey, Min Soo Lim, Jeffrey Joseph Rohde, Alexander J. Rupprecht

Chemistry Faculty Publications and Presentations

Scientific success in the field of chemistry depends upon the mastery of a wide range of soft skills, most notably scientific writing and speaking. However, training for scientific communication is typically limited at the undergraduate level, where students struggle to express themselves in a clear and logical manner. The underlying issue is deeper than basic technical skills; rather, it is a problem of students’ unawareness of a fundamental and strategic framework for writing and speaking with a purpose. The methodology has been implemented for individual mentorship and in our regional summer research program to deliver a blueprint of thought and …

A Study Of Cannabigerolic Acid And Its Derivatives Via Raman Spectroscopy And Density Functional Theory, Trevor Wolfe

Honors Theses

The cannabinoids are a class of molecules endogenous to the cannabis plant. Their scientific relevance has increased in recent years due to the mercurial legal status of marijuana across the United States. Some of the most known are cannabidiol (CBD), δ9-tetrahydrocannabinol (δ9-THC), and δ8-THC due in large part to their widespread use, especially in states where marijuana and related products are legal. However, cannabigerolic acid (CBGA) is arguably the most important cannabinoid; it is enzymatically converted into other acidic cannabinoids, which subsequently undergo non-enzymatic processes (isomerization, thermal decarboxylation, oxidation, etc.) to synthesize further cannabinoids. Although there is a wealth of …

Synthetic Investigations In Chemical Probe Development Part 1: Design And Synthesis Of Novel Triton X-405 Adenosine Conjugates; Part 2: Synthesis Of 2,8-Dihydroxychrysene, Rachel Irene Hammond

Honors Theses

Although not drugs themselves, chemical probes are a necessary tool in biomedical research for the interrogation of biological systems. In the present synthetic investigation, two chemical probes were developed – a Triton X-405 adenosine conjugate (TX-405A) and 2,8-dihydroxychrysene. The designed TX-405A conjugate was generated in four steps through tosylation and amination of TX-405 such that EDC-coupling of TX-amine with 2’,3’-Isopropylidene adenosine-5’-carboxylic acid afforded TX-405A following acetonide deprotection. The development of TX-405A represents the first report of the synthesis and utilization of a detergent-linked dosimeter. The synthesis of 2,8-dihydroxychrysene provided an in-depth exploration on the unique reactivity of chrysene. The desired …

Ab Initio Study Of The Rotation Of The C≡C Group In Benzvalyne, Advait Praveen

Honors Theses

For benzvalyne, we have characterized the minima and transition states of the molecule using the B3LYP, MP2, and M06-2X methods and aug-cc-pVTZ basis set. This was done by calculating the energy of the molecule while rotating the alkyne bond contained within it. After the initial rotation, optimized parameters for the molecule are found. Following this, imaginary frequencies were attempted to be found at the local maximum produced by the graph of the Energy v. rotation angle. Should the negative frequencies be found, the energy of the molecule will be characterized by the CCSD (T) method and aug-cc-pVQZ basis sets. This …

Lc-Ms Identification Of Serum Proteins Adsorbed Onto Ionic Liquid-Coated Nanoparticles, Anh M. Hoang

Honors Theses

Nanocarriers are promising candidates for drug delivery due to their size and tunable surface characteristics. However, when they are intravenously injected, few particles make it to their designated location. This is because upon entering the bloodstream, the serum in the blood, which is rich with a diversity of proteins, adsorbs onto the particles’ surfaces forming a protein corona. Many of the attached proteins trigger the mobile immune system and are removed by macrophages, and many particles are then filtered out by the liver and kidneys. Ionic Liquids (ILs), which consist of asymmetric, bulky components that are liquid

Computational Investigations Into Astrochemical Inorganic Oxides, Ammonia Borane, And Genetic Algorithms, E. Michael Valencia

Honors Theses

The formulations of quantum mechanics in the early 1900s were exciting theoretical discoveries, but were not practical to apply until the advent of computers and the subsequent computational methods in 1951. With the introduction of tractable simplifications, procedures such as Hartree-Fock allowed for determination of properties of non-trivial systems. Presently, huge leads of computational power have allowed for extremely precise, quantitative work that can be applied to the human body, synthesis, or even astrochemical processes. This thesis presents works concerning 1) the history of quantum mechanics; 2) a brief primer on computational chemistry and its methods; 3) inorganic oxides in …

Nitro-Aromatic Polymers For Conversion-Style Battery Cathodic Materials, Brady P. Samuelson

Honors Thesis

The development of organic electrode materials in rechargeable batteries has seen a resurgence in recent decades. This spike in interest is mostly due to the increased investments in renewable energy sources, grid-scale energy storage, and the rapid transition to electric vehicles. Current lithium battery cathode materials typically use some form of lithium metal oxide (specific capacity: 272 mAh g^-1 which has problems with limited capacity, thermal runaway, and an unreliable supply chain. Our research group’s solution involves investigating new lightweight, organic redox groups combined with a conductive polymer backbone to serve as a possible replacement for the cathode in …

Synthesis And Transition Metal-Catalyzed Coupling Of A-Chloro-B-Lactones, Tyler Lynn

Honors Projects

No abstract provided.

Relating Detonation Parameters To The Detonation Synthesis Of Silicon Carbide, Martin Langenderfer, Eric W. Bohannan, Jeremy Lee Watts, William Fahrenholtz, Catherine E. Johnson

Chemistry Faculty Research & Creative Works

Detonation synthesis of silicon carbide (SiC) nanoparticles from carbon liberated by negatively oxygen balanced explosives was evaluated in a 23 factorial design to determine the effects of three categorical experimental factors: (1) cyclotrimethylene-trinitramine (RDX)/2,4,6-trinitrotoluene (TNT) ratio, (2) silicon (Si) additive concentration, and (3) Si particle size. These factors were evaluated at low and high levels as they relate to the detonation performance of the explosive and the solid Si-containing phases produced. Detonation velocity and Chapman-Jouguet (C-J) detonation pressure, which were measured using rate stick plate dent tests, were evaluated. Solid detonation product mass, silicon carbide product concentration, and residual silicon …

C-H On The Oxo Ferryl Wheel: Comparison Of Pyridine And Imidazole-Substituted Ligands For C-H Activation And Functionalization, Elizabeth Milem

Electronic Theses and Dissertations

The selective and efficient transformation of hydrocarbon feedstocks is of high value for industry and research. While Shilov-type organometallic methods have facilitated this goal, systems designed after nature’s use of cheap and abundant iron-based enzymes are desired for wider-scale applications. This work establishes hydrocarbon oxidation efficiency of synthetic pyridine-based ligands (BPMEN, BPMPN) compared to commercially available TPA with in situ generated catalysts. Literature studies of traditionally synthesized BPMEN systems and initial in situ studies offered evidence for enhanced reactivity (TON) as compared to TPA. Expansion to a propyl backbone to produce BPMPN tested the increased chelate ring size’s impact on …

Computational Analysis Of A Mn-Based Electrocatalyst With Primary Amine Substituents In The Secondary Coordination Sphere For Co2 Reduction, Erin Urban

Undergraduate Honors Theses

The purpose of this research was to report the mechanism for the two-electron, two-proton conversion of CO 2 to CO and H 2 O using a manganese(I) electrocatalyst, Mn(L)(CO) 3 Br (where L = bipyridyl ligand with aryl-amine moieties installed at the 6 position of 2,2’-bipyridine), synthesized by the Jurss group, including any other competing reactions, such as the hydrogen evolution reaction (HER). The “protonation- first” and “reduction-first” pathways were considered for CO 2 RR. Density functional theory (DFT) calculations were performed to determine the redox potentials and Gibb’s free energies for each step in the mechanism for CO 2 …

Analysis Of The Light Responsive Azobenzene Peptide Nucleic Acid Duplexes, Kat Nguyen

Honors College Theses

Peptide nucleic acids (PNAs) are oligonucleotide analogues in which the sugar-phosphate backbone has been replaced by a pseudopeptide skeleton. Since PNAs use the natural nucleobases (Adenine, Thymine, Cytosine, Uracil, and Guanine) found in either DNA and/or RNA, they are able to hybridize according to Watson-Crick base-pairing to form duplexes. PNA is a promising therapeutic agent because they can function as antigene or antisense chemical agents. To further enhance their utility, we aim to incorporate a photoswitchable moiety using azobenzene. Here, we report the results of the synthesis and purification of a photoswitchable 11 mer PNA along with initial characterization efforts.

Age, Growth, Foraging, And Trophic Ecology Of Bigeye (Thunnus Obesus) And Yellowfin (Thunnus Albacares) Tuna In Continental Shelf And Slope Regions Of The Northeast U.S., Riley S. Austin

Electronic Theses and Dissertations

Traditional stock assessments require, in part, accurate knowledge of growth relationships to estimate a variety of aspects involved in population conservation management of exploited species. In addition, the local distribution and condition of top pelagic predators is driven by detection of abundant forage aggregations and along with traditional stock assessments, should be considered for effective management of marine populations. Empirical analyses of these data are severely lacking for bigeye (Thunnus obesus) and yellowfin (Thunnus albacares) tuna in the Atlantic Ocean, especially for the former. Given historical studies’ observations of these two top predators use as biological samplers due to their …

Climatic Influences On Summer Use Of Winter Precipitation By Trees, Gregory R. Goldsmith, Scott T. Allen, Sabine Braun, Rolf T. W. Siegwolf, James W. Kirchner

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Trees in seasonal climates may use water originating from both winter and summer precipitation. However, the seasonal origins of water used by trees have not been systematically studied. We used stable isotopes of water to compare the seasonal origins of water found in three common tree species across 24 Swiss forest sites sampled in two different years. Water from winter precipitation was observed in trees at most sites, even at the peak of summer, although the relative representation of seasonal sources differed by species. However, the representation of winter precipitation in trees decreased with site mean annual precipitation in both …

Fabrication Of Particulates For Detecting Trace Level Analytes In Water Using Optical Spectroscopy And For Developing Thermoelectric Materials, Mohammed Nayeem Ibnul

Electronic Theses and Dissertations

The underlying concepts developed in this thesis involve particulate fabrication of known size using a bottom-up synthesis or a top-down milling process. This bottom-up approach was used for detection of analytes in water. Conventional UV-Vis spectroscopic based detection methods require target analytes to be soluble or have enough vapor pressure for analysis in the gas phase. We achieved an order in magnitude improvement in the detection limit over the standard molybdenum blue method for phosphate and arsenate by conversion of target analytes present in solution to a solid for quantification by UV-Vis and IR spectroscopy. Furthermore, by recording a visible …

Development Of Methods For Surface Modification Of Semiconductor Photocatalysts And Biopolymers For Applications In Water Treatment And 3d Printing, Sabrina Sultana

Electronic Theses and Dissertations

Surface modifications of metal oxides and polymer substrates are widely adopted approaches to alter the properties of these materials for use with specific applications. In the first part of my thesis, I describe how we have modified the surface of magnetic particles (Fe3O4) with layers of SiO2 and TiO2 to generate photocatalysts that remove toxic chemicals from drinking water. Semiconductor photocatalysts, such as TiO2 have gained much interest over the last 20 years as promising materials for water treatment. However, a main drawback centers on the difficulty to remove the catalyst from the water which has made it very difficult …

Theoretical Aspects Of Calculation Of Photocurrent In Structures With Periodically Spaced Heterinclusions, R. Аyukhanov, A. Uteniyazov, S. Farmonov, N. Shernazarov

Karakalpak Scientific Journal

The processes of excitation of photoconductivity in structures with heteroinclusions with a band gap greater than the band gap of the base material of the matrix have been studied. Structures are studied when such macroinclusions are located periodically and are located at distances equal to the size of the inclusions. A technique has been developed and analytical expressions have been derived for calculating the photocurrent and specific photoconductivity in such structures.

Injection Depletion Effect In Semiconductors With Pair Impurity Complexes, A. Yu. Leyderman, A. Uteniyazov, R. Turmanova, M. Dauletbayev

Karakalpak Scientific Journal

The possibility of realizing the effect of injection depletion in a ⁺ -structure made on the basis of a semiconductor with paired donor-acceptor complexes is considered. It is shown that the appearance of this effect is possible under conditions of almost complete compensation of the shallow dopant donor impurity by the charge of the acceptor component of the pair complex. A necessary condition is also a strong asymmetry of the coefficients of capture of holes at the acceptor level in comparison with the coefficient of capture of electrons at the donor level.

Nonlinear Photoelasticity Processes Near Resonances At The Frequency Of Electronic Transitions From Deep Levels To The Conduction Zone, R. Аyukhanov, A. Uteniyazov, S. Farmonov, N. Shernazarov

Karakalpak Scientific Journal

The phenomenon of nonlinear photoelasticity, which consists of the occurrence of nonlinear photoelasticity coefficients comparable in magnitude to linear ones near the electronic resonance between the deep impurity levels and the bottom of the conduction zone, is considered theoretically. Analytical expressions for the Fourier decomposition coefficients of the dielectric permittivity of the crystal in the phase of the sound wave, which are proportional to the photoelasticity coefficients, are obtained. A general criterion for the nonlinear photoelasticity effect in the investigated frequency region is found numerically. It is shown that high deformation potentials of deep levels stimulate the appearance of this …

Fluorinated Molecularly Imprinted Polymer - Monomer And Polymer Synthesis For Pfoa Sorption, Sean Durbin

Liberty University Research Week

Undergraduate

Basic

A Machine Learning Based Approach To Detect The Ethereum Fraud Transactions With Limited Attributes, Rabia Musheer Aziz, Mohammed Farhan Baluch, Sarthak Patel, Pavan Kumar

Karbala International Journal of Modern Science

Ethereum smart contracts have recently received new commercial applications and a lot of attention from the scientific community. Ethereum eliminates the requirement for a trusted third party by allowing untrusted parties to expose contract details in computer code. Nonetheless, as online commerce grows, plenty of fraudulent activities, such as money laundering, bribery, and phishing, emerge as major threats to trade security. For correctly recognizing fraudulent transactions, this paper developed a Light Gradient Boosting Machine (LGBM) technique-based model. The modified LGBM model optimized the parameters of Light GBM using the Euclidean distant structured estimation approach. This paper also examines the performance …

A Bi-Level Data Lowering Method To Minimize Transferring Big Data In The Sensors Of Iot Applications, Ali Kadhum M. Al-Qurabat, Ali Kadhum Idrees, Abdallah Makhoul, Chady Abou Jaoude

Karbala International Journal of Modern Science

In the IoT era, the number of devices connected to it continues to grow significantly. This can lead to an increase in the amount of reported data by these IoT devices. The reported data by the Sensor Nodes (SNs) to the Gateway (GW) drives these IoT sensors to consume their energy and storage. These problems can be solved by reducing the amount of data in the source nodes in order to reduce both the amount of energy consumed and the amount of storage required. Energy consumption represents one aspect of the Quality of Service (QoS) in the sensor nodes of …

An Economical Source For Peroxidase: Maize Cobs, Hathama Razooki Hasan, Ali Waleed Al- Ani

Karbala International Journal of Modern Science

According to the current situation of peroxidase (POD), the relevant studies on this enzyme indicated its importance as a tool in clinical biochemistry and different industrial fields. Most of these studies used the fruits and vegetables as source of this enzyme. So that in order to couple the growing requirements for POD with the recent demands for reduc-ing disposal volume by recycling the plant waste, the aim of the present study was to extract POD through management of municipal bio-waste of Iraqi maize species. A simple, green and economical method was used to extract this enzyme. Our results revealed that …

Efficient Removal Of Common Organic Pollutants From Water By Zn-Doped Tio2 Nanoparticles With Different Applications, Khaled Elgendy, Ibrahim Elmehasseb, Saleh Kandil

Karbala International Journal of Modern Science

Water purification via adsorption without energy consumption was considered a green process. Zn-doped TiO2 nanoparticles were fabricated by the Sol-gel method and characterized by different analysis techniques. Zinc doping of TiO2 increases the surface area to 26.7m2g-1 with adsorption results, 75.1%, 71.1%, and 68.2% for methylene blue, ofloxacin, and SLS, respectively. Variable affecting factors on adsorption have been studied. The adsorption behavior fitted with Langmuir and Freundlich equations than Temkin isotherm, indicating the preferred heterogeneous adsorption at equivalent adsorbent sites. The application of nanoparticles in many synthetic specimens of pollutants gave excellent removal results, which exceeded 75% of detoxification.

Synthesis Of Cuo/Zno And Mgo/Zno Core/Shell Nanoparticles With Plasma Jets And Study Of Their Structural And Optical Properties, Raghad S. Mohammed, Kadhim A. Aadim, Khalid A. Ahmed

Karbala International Journal of Modern Science

This paper reports the synthesis of CuO/ZnO and MgO/ZnO core/shell nanoparticles using atmospheric plasma jets. The characterization of the synthesized CuO/ZnO and MgO/ZnO core/shell nanoparticles were confirmed by a series of techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray dispersive spectroscopy (EDS), transmission electron microscopy (TEM), and UV–Vis spectroscopy. The XRD analysis confirmed no other peaks related to the secondary phases for CuO, MgO, or ZnO, indicating the purity of these nanoparticles. Additionally, EDX analysis confirmed the formation of high purity CuO/ZnO and MgO/ZnO core/shell nanoparticles. The surface morphology, which represented the high agglomeration rate, was investigated using …