Chemistry Commons^™

Catalytic Activity Of Ethylbenzene With Product Selectivity By Gold Nanoparticlessupported On Zinc Oxide, Afiq Anwar, Azman Ma'amor, H.N.M. Ekramul Mahmud, Wan Jefrey Basirun, Iskandar Abdullah

Turkish Journal of Chemistry

The oxidation of ethylbenzene (EB) using tert-butyl hydroperoxide as the oxidizing agent was carried out in presence of gold nanoparticles (3 nm) supported on zinc oxide in acetonitrile solution. A higher selectivity towards acetophenone (ACP) as the major product, and a moderate selectivity towards other products such as 1-phenylethanol (PE), benzaldehyde (BZL), and benzoic acid (BzA) were observed using the prepared Au/ZnO nanocatalysts at 100 °C for 24 h. It is suggested the reaction produces an intermediate product, which is dimethylethyl-1-phenylethyl peroxide through a radical mechanism. A small amount of benzaldehyde was observed because benzaldehyde went autoxidation to form benzoic …

Ferrihydrite/Ultrasound Activated Peroxymonosulfate For Humic Acid Removal, Hang Yang, Yi Zhang, Shibin Xia

Turkish Journal of Chemistry

In this study, ferrihydrite/ultrasound (US) system was used to activate peroxymonosulfate (PMS) to treat humic acid (HA) in artificial aqueous. The physical and chemical properties of ferrihydrite were characterized using SEM, zeta potential, BET, XRD, FTIR, and XPS analysis. A series of experiments were conducted to evaluate the effect of various factor on HA removal, including dosage of ferrihydrite, PMS concentration and pH value. The combination uses of US and ferrihydrite had obvious synergistic effect for HA removal. Under ferrihydrite/US/PMS system, nonthermal effect of US played the main role for HA removal. According to the result of radical quenching experiment, …

การผลิตวานิลลินจากเคอร์คูมินอยด์ในขมิ้นชันโดยโอโซโนไลซิส, ภัทรวดี รุ่งศรีทอง

Chulalongkorn University Theses and Dissertations (Chula ETD)

ในปัจจุบันการสังเคราะห์วานิลลินใช้วัตถุดิบตั้งต้นจากอุตสาหกรรมปิโตรเลียม ซึ่งวานิลลินสังเคราะห์นี้ ใช้สำหรับเป็นสารแต่งกลิ่นวานิลลากันอย่างแพร่หลายในอุตสาหกรรมอาหาร อย่างไรก็ตาม การใช้วัตถุดิบตั้งต้นที่สามารถเกิดขึ้นใหม่ได้ตามธรรมชาตินั้น เป็นแนวทางที่มีความยั่งยืนมากกว่า ตามหลักการไบโอรีไฟเนอรี ในงานวิจัยนี้ ผู้วิจัยสนใจศึกษาการผลิตวานิลลินด้วยปฏิกิริยาโอโซโนไลซิส โดยใช้เคอร์คูมินอยด์ที่อยู่ในขมิ้นชันเป็นวัตถุดิบตั้งต้น ขมิ้นชันเป็นพืชสมุนไพรที่ปลูกมากในประเทศไทยและประเทศในแถบเอเชียตะวันออกเฉียงใต้ ซึ่งเคอร์คูมินอยด์นั้นจะประกอบไปด้วย เคอร์คูมิน (curcumin), ดีเมทอกซีเคอร์คูมิน (demethoxycurcumin), และบิสดีเมทอกซีเคอร์คูมิน (bisdemethoxycurcumin) ผู้วิจัยเริ่มจากการสกัดเคอร์คูมินอยด์จากขมิ้นชันผงน้ำหนักประมาณ 45 กรัม ด้วยเทคนิคซอกเลท (Soxhlet extraction) โดยใช้เฮกเซนในการกำจัดน้ำมันหอมระเหยในขมิ้นชัน จากนั้นใช้เมทานอลสำหรับสกัดเคอร์คูมินอยด์ และได้ของผสมเคอร์คูมินอยด์ปริมาณ 9.2% (โดยน้ำหนัก) จากการวิเคราะห์เคอร์คูมินอยด์ที่สกัดได้ด้วยเทคนิคโครมาโทกราฟีของเหลวสมรรถนะสูง (high-perfomance liquid chromatography) พบว่าประกอบไปด้วย เคอร์คูมิน ดีเมทอกซีเคอร์คูมิน และบิสดีเมทอกซีเคอร์คูมิน ในปริมาณ 46%, 22%, และ 32% ตามลำดับ นำของผสมเคอร์คูมินอยด์ดังกล่าวมาทำปฏิกิริยาโอโซโนไลซิสในตัวทำละลายเมทานอลที่อุณหภูมิ 0 องศาเซลเซียสและรีดิวซ์ด้วยไดเมทิลซัลไฟด์ (dimethyl sulfide) ได้ผลิตภัณฑ์เป็นของผสมระหว่างวานิลลินและ 4-ไฮดรอกซีเบนซาลดีไฮด์ (4-hydroxybenzaldehyde) ทำบริสุทธิ์ของผสมที่ได้ด้วยเทคนิคคอลัมน์โครมาโทกราฟี โดยใช้ซิลิกาเจลเป็นวัฏภาคนิ่งและใช้ตัวทำละลายผสมไดคลอโรเมเทน/เมทานอล/กรดแอซีติก (98.5:1.0:0.5 โดยปริมาตร) เป็นวัฏภาคเคลื่อนที่ สามารถแยกสารบริสุทธิ์วานิลลิน 63% และ 4-ไฮดรอกซีเบนซาลดีไฮด์ 97% ผู้วิจัยยังได้ศึกษาการตกผลึกเพื่อเป็นทางเลือกสำหรับการทำบริสุทธิ์ต้นทุนต่ำสำหรับของผสมหลังผ่านปฏิกิริยาโอโซโนไลซิส พบว่าสามารถตกผลึก 4-ไฮดรอกซีเบนซาลดีไฮด์ให้บริสุทธิ์ในปริมาณ 62% ด้วยตัวทำละลายผสมคลอโรฟอร์ม/เฮกเซน (1:1 โดยปริมาตร) อย่างไรก็ตาม ยังมีวานิลลินและ 4-ไฮดรอกซีเบนซาลดีไฮด์ เหลืออยู่ในสารละลายหลังตกผลึก (mother liquor) ในปริมาณ 58% และ 32% ตามลำดับ โดยสรุปผู้วิจัยประสบความสำเร็จในการผลิตวานิลลินและ 4-ไฮดรอกซีเบนซาลดีไฮด์จากขมิ้นชันซึ่งเป็นวัตถุดิบตั้งต้นที่สามารถเกิดขึ้นใหม่ได้ ผ่านปฏิกิริยาโอโซโนไลซิส นับเป็นแนวทางเพิ่มมูลค่าพืชสมุนไพรราคาถูกให้เป็นสารเคมีที่มีมูลค่าสูงขึ้นตามหลักการไบโอรีไฟเนอรี

From Evaluating The Performance Of Approximations In Density Functional Theory To A Machine Learning Design, Pedram Tavazohi

Graduate Theses, Dissertations, and Problem Reports (ETD)

Density-functional theory (DFT) has gained popularity because of its ability to predict the properties of a large group of materials a priori. Even though DFT is exact, there are inaccuracies introduced into the theory due to the approximations in the exchange-correlation (XC) functionals. Over the 50 years of its existence, scientists have tried to improve the design of the XC functionals. The errors introduced by these functionals are not consistent across all types of solid-state materials. In this project, a high throughput framework was utilized to compare the theoretical DFT predictions with the experimental results available in the Inorganic Crystal …

Mechanism For Selective Binding Of Aromatic Compounds On Oxygen-Rich Graphene Nanosheets Based On Molecule Size/Polarity Matching, Heyun Fu, Bingyu Wang, Dongqiang Zhu, Zhicheng Zhou, Shidong Bao, Xiaolei Qu, Yong Guo, Lan Ling, Shourong Zheng, Pu Duan, Jingdong Mao, Klaus Schmidt-Rohr, Shu Tao, Pedro J.J. Alvarez

Chemistry & Biochemistry Faculty Publications

Selective binding of organic compounds is the cornerstone of many important industrial and pharmaceutical applications. Here, we achieved highly selective binding of aromatic compounds in aqueous solution and gas phase by oxygen-enriched graphene oxide (GO) nanosheets via a previously unknown mechanism based on size matching and polarity matching. Oxygen-containing functional groups (predominately epoxies and hydroxyls) on the nongraphitized aliphatic carbons of the basal plane of GO formed highly polar regions that encompass graphitic regions slightly larger than the benzene ring. This facilitated size match–based interactions between small apolar compounds and the isolated aromatic region of GO, resulting in high binding …

Toxic Effects Of Silver Ions On Early Developing Zebrafish Embryos Distinguished From Silver Nanoparticles, Martha S. Johnson, Preeyaporn Songkiatisak, Pavan Kumar Cherukuri, Xiao-Hong Nancy Xu

Chemistry & Biochemistry Faculty Publications

Currently, effects of nanomaterials and their ions, such as silver nanoparticles (Ag NPs) and silver ions (Ag⁺), on living organisms are not yet fully understood. One of the vital questions is whether nanomaterials have distinctive effects on living organisms from any other conventional chemicals (e.g., their ions), owing to their unique physicochemical properties. Due to various experimental protocols, studies of this crucial question have been inconclusive, which hinders rational design of effective regulatory guidelines for safely handling NPs. In this study, we chronically exposed early developing zebrafish embryos (cleavage-stage, 2 hours post-fertilization, hpf) to a dilution series of …

Nrlmsis 2.1: An Empirical Model Of Nitric Oxide Incorporated Into Msis, J. T. Emmert, M. Jones Jr., D. E. Siskind, D. P. Drob, J. M. Picone, M. H. Stevens, S. M. Bailey, S. Bender, P. F. Bernath, B. Funke, M. E. Hervig, K. Pérot

Chemistry & Biochemistry Faculty Publications

We have developed an empirical model of nitric oxide (NO) number density at altitudes from ∼73 km to the exobase, as a function of altitude, latitude, day of year, solar zenith angle, solar activity, and geomagnetic activity. The model is part of the NRLMSIS® 2.1 empirical model of atmospheric temperature and species densities; this upgrade to NRLMSIS 2.0 consists solely of the addition of NO. MSIS 2.1 assimilates observations from six space-based instruments: UARS/HALOE, SNOE, Envisat/MIPAS, ACE/FTS, Odin/SMR, and AIM/SOFIE. We additionally evaluated the new model against independent extant NO data sets. In this paper, we describe the formulation and …

A Local Mode Study Of Ring Puckering Effects In The Infrared Spectra Of Cyclopentane, Edwin L. Sibert Iii, Peter F. Bernath

Chemistry & Biochemistry Faculty Publications

We report and interpret recently recorded high-resolution infrared spectra for the fundamentals of the CH₂ scissors and CH stretches of gas phase cyclopentane at −26.1 and −50 ^○C, respectively. We extend previous theoretical studies of this molecule, which is known to undergo barrierless pseudorotation due to ring puckering, by constructing local mode Hamiltonians of the stretching and scissor vibrations for which the frequencies, couplings, and linear dipoles are calculated as functions of the pseudorotation angle using B3LYP/6-311++(d,p) and MP2/cc-pVTZ levels of theory. Symmetrization (D_5h) of the vibrational basis sets leads to simple vibration/pseudorotation Hamiltonians whose solutions …

The Acute Physiological Response Of Polar Bears To Helicopter Capture, John P. Whiteman, Henry J. Harlow, George M. Durner, Eric V. Regehr, Steven C. Amstrup, Anthony M. Pagano, Merav Ben-David

Biological Sciences Faculty Publications

Many wildlife species are live captured, sampled, and released; for polar bears (Ursus maritimus) capture often requires chemical immobilization via helicopter darting. Polar bears reduce their activity for approximately 4 days after capture, likely reflecting stress recovery. To better understand this stress, we quantified polar bear activity (via collar‐mounted accelerometers) and body temperature (via loggers in the body core [T_abd] and periphery [T_per]) during 2–6 months of natural behavior, and during helicopter recapture and immobilization. Recapture induced bouts of peak activity higher than those that occurred during natural behavior for 2 of 5 bears, …

Application Of Chemostratigraphic Methods To Floodplain Alluvial Deposits Within The Big Harris Creek Basin, North Carolina, Samantha N. Sullivan, Jerry R. Miller, Carmen L. Huffman

Chemistry & Biochemistry Faculty Publications

Big Harris Creek, North Carolina, possesses a geomorphic history and alluvial stratigraphic record similar to many drainages in southern Appalachian Piedmont. An approximately 1 km reach of Upper Stick Elliott Creek, a tributary to Big Harris Creek, was used herein to (1) explore the use of chemostratigraphic methods to define and correlate late Holocene alluvial deposits along this relatively uncontaminated rural stream containing legacy sediments (historic, anthropogenically derived deposits), and (2) interpret depositional floodplain processes within small (<10 km²), headwater drainages. The lithofacies within four floodplain sections were described in channel banks and sampled at about 5 cm intervals. …

On The Stratospheric Chemistry Of Midlatitude Wildfire Smoke, Susan Soloman, Kimberlee Dube, Kane Stone, Pengfei Yu, Doug Kinnison, Owen B. Toon, Susan E. Strahan, Karen H. Rosenlof, Robert Portmann, Sean Davis, William Randel, Peter Bernath, Chris Boone, Charles G. Bardeen, Adam Bourassa, Daniel Zawada, Doug Degenstein

Chemistry & Biochemistry Faculty Publications

Massive Australian wildfires lofted smoke directly into the stratosphere in the austral summer of 2019/20. The smoke led to increases in optical extinction throughout the midlatitudes of the southern hemisphere that rivalled substantial volcanic perturbations. Previous studies have assumed that the smoke became coated with sulfuric acid and water and would deplete the ozone layer through heterogeneous chemistry on those surfaces, as is routinely observed following volcanic enhancements of the stratospheric sulfate layer. Here, observations of extinction and reactive nitrogen species from multiple independent satellites that sampled the smoke region are compared to one another and to model calculations. The …

Ozonized Biochar Filtrate Effects On The Growth Of Pseudomonas Putida And Cyanobacteria Synechococcus Elongatus Pcc 7942, Oumar Sacko, Nancy L. Engle, Timothy J. Tschaplinski, Sandeep Kumar, James Weifu Lee

Chemistry & Biochemistry Faculty Publications

Background

Biochar ozonization was previously shown to dramatically increase its cation exchange capacity, thus improving its nutrient retention capacity. The potential soil application of ozonized biochar warrants the need for a toxicity study that investigates its effects on microorganisms.

Results

In the study presented here, we found that the filtrates collected from ozonized pine 400 biochar and ozonized rogue biochar did not have any inhibitory effects on the soil environmental bacteria Pseudomonas putida, even at high dissolved organic carbon (DOC) concentrations of 300 ppm. However, the growth of Synechococcus elongatus PCC 7942 was inhibited by the ozonized biochar filtrates at …

The Hitran2020 Molecular Spectroscopic Database, I. E. Gordon, L. S. Rothman, R. J. Hargreaves, R. Hashemi, E. V. Karlovets, F. M. Skinner, E. K. Conway, C. Hill, R. V. Kochanov, Y. Tan, P. Wcisło, A.A. Finenko, K. Nelson, P. F. Bernath, M. Birk, V. Boudon, A. Campargue, K. V. Chance, A. Coustenis, B. J. Drouin, J.-M. Flaud, R. R. Gamache, J. T. Hodges, D. Jacquemart, E. J. Mlawer, A. V. Nikitin, V.I. Perevalov, M. Rotger, J. Tennyson, G. C. Toon, H. Tran, V. G. Tyuterev, E. M. Adkins, A. Baker, A. Barbe, E. Canè, A. G. Császár, A. Dudaryonok, O. Egorov, A. J. Fleisher, H. Fleurbaey, A. Foltynowicz, T. Furtenbacher, J. J. Harrison, J.M. Hartmann, V.- M. Horneman, X. Huang, T. Karman, J. Karns, S. Kassi, I. Kleiner, V. Kofman, F. Kwabia-Tchana, N.N. Lavrentieva, T. J. Lee, D. A. Long, A. A. Lukashevskaya, O. M. Lyulin, V. Yu Makhnev, W. Matt, S. T. Massie, M. Melosso, S. N. Mikhailenko, D. Mondelain, H.S.P. Müller, O. V. Naumenko, A. Perrin, O. L. Polyansky, E. Raddaoui, P. L. Raston, Z. D. Reed, M. Rey, C. Richard, R. Tóbiás, I. Sadiek, D. W. Schwenke, E. Starikova, K. Sung, F. Tamassia, S. A. Tashkun, J. Vander Auwera, I.A. Vasilenko, A.A. Vigasin, G.L. Villanueva, B. Vispoel, G. Wagner, A. Yachmenev, S. N. Yurchenko

Chemistry & Biochemistry Faculty Publications

The HITRAN database is a compilation of molecular spectroscopic parameters. It was established in the early 1970s and is used by various computer codes to predict and simulate the transmission and emission of light in gaseous media (with an emphasis on terrestrial and planetary atmospheres). The HITRAN compilation is composed of five major components: the line-by-line spectroscopic parameters required for high-resolution radiative-transfer codes, experimental infrared absorption cross-sections (for molecules where it is not yet feasible for representation in a line-by-line form), collision-induced absorption data, aerosol indices of refraction, and general tables (including partition sums) that apply globally to the data. …

Here, There, And Everywhere: Probing Ubiquitin-Cavitand Binding Via 15n-1h Hsqc, Julia Didziulis

Scripps Senior Theses

Ubiquitination and other post-translational modifications play a major role in the proliferation of many neurodegenerative diseases, developmental disorders, and cancers, and as such are subjects of recently increased biochemical interest. Expanding upon such research, this study confirmed a robust method of ubiquitin expression and purification, then used 15N-1H HSQC to analyze ubiquitin samples containing varying concentrations of a deep cavitand with affinity for lysine and arginine side chains. In the pure ubiquitin spectrum, arginine side chain chemical shifts were detected in the nitrogen 80-85 ppm range and lysine side chain signals were undetected. However, upon introduction of the cavitand, collection …

Trends In Biomedical Analysis Of Red Blood Cells – Raman Spectroscopy Against Other Spectroscopic, Microscopic And Classical Techniques, Jakub Dybas, Fatih Celal Alcicek, Aleksandra Wajda, Magdalena Kaczmarska, Anna Zimna, Katarzyna Bulat, Aneta Blat, Tetiana Stepanenko, Tasnim Mohaissen, Ewa Szczesny-Malysiak, David Perez-Guaita, Bayden R. Wood, Katarzyna Maria Marzec

Articles

Application of modern and innovative spectroscopic and microscopic approaches to biomedical analysis opens new horizons and sheds new light on many unexplored scientific territories. In this review, we critically summarize up-to-date Raman-based methodologies for red blood cells (RBCs) analysis used in biology and medicine, and compare them with both classical, as well as other spectroscopic and microscopic approaches. The main emphasis is placed on the advantages, disadvantages and capabilities of each technique for detection of RBC deteriorations and RBC-related diseases. Although currently used classical techniques of medical analysts serve as a gold standard for clinicians in diagnosis of erythropathies, they …

Charge Transfer Mediated Triplet Excited State Formation In Donor-Acceptor-Donor Bodipy: Application For Recording Of Holographic Structures In Photopolymerizable Glass, Tatsiana Mikulchyk, Safakath Karuthedath, Catherine S.P. De Castro, Andrey A. Buglak, Aimee Sheehan, Aaron Wieder, FréDéRic Laquai, Izabela Naydenova, Mikhail Filatov

Articles

Donor–acceptor–donor BODIPY triads bearing anthracene or pyrene as electron donating subunits were prepared through a stepwise synthesis. Photoinduced electron transfer and formation of long-lived triplet excited states via spin–orbit charge transfer intersystem crossing (SOCT-ISC) was studied by steady-state and ultrafast pump-probe spectroscopy and further supported by DFT computations. New BODIPYs were found to form triplet states and sensitize singlet oxygen in both polar and non-polar solvents which is unusual for photosensitizers operating via SOCT-ISC. BODIPY-anthracene triad (ABA) was used as a photosensitizer component in a photopolymerizable glass that was prepared by a four-step sol–gel process. ABA in combination with N …

Development Of Nanodisc Affinity Capillary Electrophoresis To Study The Interaction Of Giα Protein With Cell Membranes, Bethany R. Emeigh

Graduate Student Theses, Dissertations, & Professional Papers

Guanine nucleotide-binding proteins, or G-proteins, are crucial to cell signaling by acting as molecular switches through interactions with membrane-bound receptors. G-proteins have become of greater interest due to the possibility of novel drug targets. The G-protein alpha subunit, Gα, binds GTP before localizing to the membrane to interact with other G-protein subunits and G-protein-coupled receptors (GPCRs). Gi lacks a hydrophobic region to promote localization to the membrane, but a co-translational lipidation of the N-terminal residue stabilizes this interaction.

Protein interactions with biological membranes are challenging to study due to the complex structure of membranes and the often-limited quantities of the …

Polybenzodiazine Aerogels: All-Nitrogen Analogues Of Polybenzoxazines Synthesis, Characterization, And High-Yield Conversion To Nanoporous Carbons, Vaibhav A. Edlabadkar, Saidulu Gorla, Rushi U. Soni, A. B.M.Shaheen Ud Doulah, Joseph Gloriod, Samuel Hackett, Nicholas Leventis, Chariklia Sotiriou-Leventis

Chemistry Faculty Research & Creative Works

Tetrahydroquinazoline (THQ) was designed as an all-nitrogen analogue of main-stream benzoxazine monomers. THQ solutions in DMF gelled at 100 °C via HCl-catalyzed ring-opening polymerization to polybenzodiazine (PBDAZ) wet gels, which were dried in an autoclave with supercritical fluid CO₂ to aerogels. These as-prepared PBDAZ-100 aerogels undergo ring-fusion aromatization at 240 °C under O₂. This oxidized form is referred to as PBDAZ-240. Chemical identification of PBDAZ-100 and PBDAZ-240 relied on consideration of all nine possible polymerization pathways, in combination with elemental analysis, infrared and solid-state 13C NMR spectroscopy, and 15N NMR spectroscopy of aerogels from the selectively 15N-enriched …

Instrumental Analysis, David T. Harvey

Chemistry & Biochemistry Faculty Publications

Instrumental analysis is a field of analytical chemistry that investigates analytes using scientific instruments.

Finding Combinations Of Objects Within Categories Using Edges Software, Erin M. Thorpe, Ehab Rizek, Yan Xu

Chemistry Software

Edges Software can be used to find the combinations of any objects within different categories. A combination is an arrangement of objects where order does not matter. The original intent of this software was to provide the combinations of proteins within different pathways to aid in building a protein-(target)-protein network where protein nodes are connected to each other through their common pathway edges. This software can analyze tens of thousands of rows of excel data in just a few minutes and provide an excel output that contains all the combinations of objects within the different categories. This output can then …

Scale-Up Of Flow-Electrode Capacitive Deionization Method For Hard Water Softening, Noah Henry

Williams Honors College, Honors Research Projects

This study’s purpose is to further document a capacitive deionization design that could be capable of purifying H₂O at a household scale where clean water is otherwise unobtainable in applicable regions of the world. The hypothesis behind this study was continuously larger scaled electrochemical cell-units would increase their water softening capabilities in sustainable fashion. The trend at which performance will scale is currently unknown. The units studied were constructed using graphite plates, anion exchange membranes, cation exchange membranes, and Teflon channels. Three streams, two being CaCl₂ solutions in DI H₂O (one being concentrated with CaCl …

Sequential Block Copolymers Of Polyisobutylene And Polyolefins, Manwel Labib

Williams Honors College, Honors Research Projects

A two-step approach will be utilized to synthesize random polyolefin multiblock-copolymers. This strategy takes advantage of a,w-terminated telechelic polyolefins. Polypropylene (iPP)/polyethylene (PE) are picked because of their strength, and polyisobutylene (PIB) because of its hemocompatibility. This copolymer is theorized to make for robust bio-inert plastic, which can be used for surgical mesh implants.

Electrochemical Impedance Spectroscopy Analysis Of Corrosion Of Reinforcing Steel In Fly Ash Mortar By Means Of Transmission Line Modeling, Padraig Stack

Williams Honors College, Honors Research Projects

Electrochemical impedance spectroscopy (EIS) is an important non-destructive tool that allows for a deeper understanding of the electrochemical processes and mechanisms occurring in an electrochemical cell. Equivalent electrical circuits (EECs) are used to model the impedance data into electrical components, such as resistors and capacitors, on a circuit. Current potentiostat offers software packages that can analyze the frequency response, but the software only supports “simple” EEC that can be written as fixed electrical components in some combination of series and parallel. Park and Macdonald propose a transmission line model (TLM) that does not use lumped-element models, instead, the values of …

Probing The Production Of Intracellular Vesicles Containing Reactive Oxygen And Nitrogen Species By Electrochemical Resistive-Pulse Sensing, Rui Jia

Publications and Research

No abstract provided.

Extremophilic Fungi From Marine Environments: Underexplored Sources Of Antitumor, Anti-Infective And Other Biologically Active Agents, Lesley Ann Giddings, David J. Newman

Chemistry: Faculty Publications

Marine environments are underexplored terrains containing fungi that produce a diversity of natural products given unique environmental pressures and nutrients. While bacteria are commonly the most studied microorganism for natural products in the marine world, marine fungi are also abundant but remain an untapped source of bioactive metabolites. Given that their terrestrial counterparts have been a source of many blockbuster antitumor agents and anti-infectives, including camptothecin, the penicillins, and cyclosporin A, marine fungi also have the potential to produce new chemical scaffolds as leads to potential drugs. Fungi are more phylogenetically diverse than bacteria and have larger genomes that contain …

Synthesis And Advanced Characterization Of Energy Materials, Erik Sarnello

Graduate Research Theses & Dissertations

Catalysts are used in an extremely broad range of systems including everything from biological systems to industrial processes. An ideal catalyst offers robust stability and high activity. This work focuses on the synthesis and characterization of materials that show promise in the field of catalysis. Advanced synchrotron characterization techniques and unique experimental design are highlighted to provide foundation work that will provide the necessary information to aid in designing and fabricating catalytic materials. Supported metal nanoparticle (SMN) catalysts are enormously crucial for many catalytic applications. However, catalyst deactivation, caused by sintering and coke formation, is a ubiquitous problem that significantly …

Determining The Effects Of Chemical Exposure On Hepatocyte Mitochondrial Networks And Cell Viability, Bethany Eaton

All Master's Theses

Mitochondria are cellular organelles that are becoming more recently studied. One of their main functions is the production of energy through cellular respiration, which is crucial to cell life. However, they are also associated with numerous disease states. It is hypothesized that reactive oxygen species (ROS), largely produced in mitochondria, induce oxidative stress and affect mitochondrial morphology along with cell viability. This study compares chemical exposure of menadione, an ROS producer, and phthalates (plasticizers) on two mouse hepatocyte cell lines to determine the effects they have on mitochondrial morphology and cell viability. Three experiments were performed to analyze the effects …

Synthesis Of Rna Nucleotides Under Probable Prebiotic Conditions, Ryan Stimson

Williams Honors College, Honors Research Projects

RNA being composed of multiple covalently linked nucleotides is thought to have been a precursor to life circa 4.3-3.8 billion years ago. Non-enzymatically formed adenosine monophosphate (AMP), more specifically, is a vitally important subtopic of the self-assembly of the first RNA sequence. The goal of this study was to synthesize AMP non-enzymatically under benign conditions that are likely to have existed on early Earth. In this experiment, 3’,5’-cAMP was successfully formed using wet-dry cycles at 80°C paired with the minerals zeolite beta, hydroxyapatite, and aerosil 300 in the presence of adenosine, urea, and pyrophosphate. A nuclear magnetic resonance spectrometer was …

The Influence Of Hydrogen Peroxide On The Enrichment Of Fe(Iii) Reducing Bacteria From Acid Mine Drainage, Susami Seth

Williams Honors College, Honors Research Projects

It is hypothesized that the ocean of Europa, a Jupiter moon, hosts bacteria on its oceanic floor. Understanding how Fe(III) reducing bacteria (FeRB) from AMD utilize organic materials within its surrounding environment outlines how FeRB could thrive and tolerate extreme conditions. FeRB are known to tolerate metals and highly reactive oxidants species (ROS), but in this experiment, H₂O₂ was the experimental factor to further test FeRB tolerance. H₂O₂ is a common ROS and is damaging to living material such as proteins, DNA, and RNA. A range of H₂O₂ concentrations were fed …

Design And Synthesis Of Α-Anomeric Diacetylene-Containing Glycosides As Photopolymerizable Molecular Gelators, Guijun Wang, Dan Wang, Anji Chen, Ifeanyi S. Okafor, Lalith Palitha Samankumara

Chemistry & Biochemistry Faculty Publications

Glycolipids with diacetylene functional groups are fascinating compounds with many practical uses. Among these, diacetylene-containing gelators are especially important because they can form photopolymerizable gels, which are useful stimuli-responsive materials. Inspired by the unique properties of diacetylene-containing gelators and to understand the structural influences especially the location of the diacetylene functional groups on the self-assembling properties, a series of 15 novel N-acetyl-d-glucosamine derivatives with the diacetylene functional group introduced at the anomeric position were designed and synthesized. The diacetylene function is attached to the sugar through α-glycosylation with the distance from the anomeric oxygen being varied from one, two, …