Chemistry Commons^™

A Procedure For Computing Hydrocarbon Strain Energies Using Computational Group Equivalents, With Application To 66 Molecules, Paul R. Rablen

Chemistry & Biochemistry Faculty Works

A method is presented for the direct computation of hydrocarbon strain energies using computational group equivalents. Parameters are provided at several high levels of electronic structure theory: W1BD, G-4, CBS-APNO, CBS-QB3, and M062X/6-31+G(2df,p). As an illustration of the procedure, strain energies are computed for 66 hydrocarbons, most of them highly strained.

Biophysical And X-Ray Structural Studies Of The (Gggtt)3ggg G-Quadruplex In Complex With N-Methyl Mesoporphyrin Ix, Linda Yingqi Lin , '20, S. Mccarthy, Barrett M. Powell , '18, Yanti Manurung , '20, Irene M. Xiang , '18, W. L. Dean, B. Chaires, Liliya A. Yatsunyk

Chemistry & Biochemistry Faculty Works

The G-quadruplex (GQ) is a well-studied non-canonical DNA structure formed by G-rich sequences found at telomeres and gene promoters. Biological studies suggest that GQs may play roles in regulating gene expression, DNA replication, and DNA repair. Small molecule ligands were shown to alter GQ structure and stability and thereby serve as novel therapies, particularly against cancer. In this work, we investigate the interaction of a G-rich sequence, 5’-GGGTTGGGTTGGGTTGGG-3’ (T1), with a water-soluble porphyrin, N-methyl mesoporphyrin IX (NMM) via biophysical and X-ray crystallographic studies. UV-vis and fluorescence titrations, as well as a Job plot, revealed a 1:1 binding stoichiometry with an …

Tuning The Activity And Stability Of Platinum Nanoparticles Toward The Catalysis Of The Formic Acid Electrooxidation, Islam M. Al-Akraa, Bilquis A. Al-Qodami, Santosh Sridhar Mysore Dr, R. Viswanatha Dr, Abdul Kareem Thottoli, Ahmad M. Mohammad

Chemical Engineering

No abstract provided.

Convergent Synthesis Of Anaephene B, Mason A. Baber

Honors Program Theses

As strains of bacteria continuously evolve and become resistant to modern antibiotics, there exists a need for the development of new treatments to combat bacterial infection. Staphylococcus aureus (S. aureus) is known to develop such resistance and remains a leading cause of invasive infections and biofilm formation on prosthetic medical devices. In 2018, Brumley and Spencer et al. isolated anaephenes A–C, natural products from a marine bacterium. Anaephene B was of particular interest as it was the only member of the series to demonstrate moderate antibacterial activity against S. aureus (MIC = 6.1 μg/mL). Because of the potential clinical utility …

Nanodiamonds And Carbon Nano-Onions Ceramic Composites And Their Applications, Ibrahim Munkaila Abdullahi

Masters Theses

"Luminescent nanodiamonds are photostable non-blinking fluorescent biocompatible, non-toxic, functional Zable materials made from high-pressure high temperature (HPHT) microcrystalline diamonds. For long, the scientific community has been investigating for a clean, efficient and cost-effective technique to reduce the size of fluorescent microcrystalline diamond into nanodiamonds. Their color center, responsible for the fluorescent properties are crucial for their applications, including biomedical imaging, nano sensing, quantum computing etc, and therefore should not be affected significantly by the method of size reduction applied. A novel size reduction technique that is based on explosive fragmentation was developed and the corresponding fragmented diamonds obtained were characterized …

Exploring The Multiplex Detection Capabilities Of Raman Spectroscopy On Mock Street Samples Containing Illicitly Manufactured Fentanyls, Mia Laverne Williams Burnett

Browse all Theses and Dissertations

Illicitly manufactured fentanyls (IMFs) have become a global and local epidemic and have recently caused an increase in the number of accidental exposures and overdoses in first responders and the community. The aim of the research is to explore a method to discriminate between IMFs and cutting agents in mock street samples using Raman Spectroscopy. Predominant Raman bands corresponding to the structural moieties of each individual illicit, licit drugs, and cutting agents were tracked, then used to discriminate between varying components in a mock street sample. In conclusion, discrimination between the components in the mixture was obtained using Raman Spectroscopy. …

Clinical And Pharmaceutical Applications Of Affinity Ligands In Capillary Electrophoresis: A Review, Chenhua Zhang, Ashley G. Woolfork, Kyungah Suh, Susan Ovbude, Cong Bi, Marawan Elzoeiry, David S. Hage

David Hage Publications

Affinity capillary electrophoresis (ACE) is a separation technique that combines a biologically-related binding agent with the separating power and efficiency of capillary electrophoresis. This review will examine several classes of binding agents that have been used in ACE and applications that have been described for the resulting methods in clinical or pharmaceutical analysis. Binding agents that will be considered are antibodies, aptamers, lectins, serum proteins, carbohydrates, and enzymes. This review will also describe the various formats in which each type of binding agent has been used in CE, including both homogeneous and heterogeneous methods. Specific areas of applications that will …

A Brief Introduction To The Applications Of Small Organic Molecules As Food Additives, Zhou Zhou

Open Educational Resources

A new chapter in Introductory Organic Chemistry course. Lecture PowerPoint file and laboratory document are also included in this work.

• The goal of this chapter is to cover the basic ground of the food additives from the perspective of organic chemistry. This chapter has three parts.
  • Part one: Introduction of the food additive industry including the history, definition and the purposes of food additives.
  • Part two: The terminology in food additives and in organic chemistry, how to locate trustworthy data sheets for chemicals, and how to interpret the toxicity data.
  • Part three: Different families of organic compounds used as food …

การจำลองซีเอฟดีของการดูดซับคาร์บอนไดออกไซด์และการฟื้นฟูสภาพตัวดูดซับ K2co3/Al2o3 ในฟลูอิไดซ์เบดแบบปั่นป่วนหมุนเวียนแบบครบวงจร, ชนิกานต์ วันจันทร์

Chulalongkorn University Theses and Dissertations (Chula ETD)

การเผาไหม้เชื้อเพลิงฟอสซิลเพื่อการผลิตพลังงานและกระแสไฟฟ้ายังคงเป็นสาเหตุหลักในการปลดปล่อยแก๊สคาร์บอนไดออกไซด์ เทคโนโลยีดักจับแก๊สคาร์บอนไดออกไซด์ก่อนการปล่อยสู่ชั้นบรรยากาศยังคงได้รับการพัฒนาอย่างต่อเนื่อง ในการศึกษานี้ จึงได้มุ่งเน้นการพัฒนาแบบจำลองพลศาสตร์ของไหลเชิงคำนวณของเครื่องปฏิกรณ์ฟลูอิไดซ์เบดแบบปั่นป่วนหมุนเวียนแบบครบวงจรด้วยตัวดูดซับของแข็งโพแทสเซียมคาร์บอนเนตบนตัวรองรับอะลูมินา ที่ประกอบไปด้วยส่วนหอไรเซอร์ที่มีการดูดซับแก๊สคาร์บอนไดออกไซด์ และส่วนหอดาวเนอร์ที่ใช้ในการฟื้นฟูสภาพตัวดูดซับของแข็ง ด้วยภาวะการดำเนินการที่แตกต่างกันในหอไรเซอร์และดาวเนอร์ การติดตั้งอุปกรณ์ควบคุมทางวิศวกรรม นั่นคือ วาล์วควบคุม เพื่อศึกษาผลกระทบที่มีต่ออุทกพลศาสตร์ภายในกระบวนการ โดยทำการจำลองระบบติดตั้งวาล์วแบบเลื่อนและวาล์วแบบหมุน จากผลการจำลองพบว่าระบบการติดตั้งวาล์วแบบหมุนมีการกระจายตัวของตัวดูดซับของแข็งภายในไรเซอร์อย่างหนาแน่นและสม่ำเสมอ เนื่องจากการปิดกั้นการไหลของแก๊สคาร์บอนไดออกไซด์ไปยังส่วนดาวเนอร์ส่งผลให้ทิศทางการไหลของแก๊สและของแข็งไหลในไรเซอร์ได้ดีมากขึ้น ทำให้ประสิทธิภาพการดักจับแก๊สคาร์บอนไดออกไซด์สูงขึ้น อีกทั้งพบว่าอัตราการเกิดปฏิกิริยาย้อนกลับมีผลต่อประสิทธิภาพการฟื้นฟูสภาพตัวดูดซับและอุณหภูมิภายในระบบเมื่อเวลาผ่านไป ในส่วนผลลัพธ์ของอัตราการป้อนตัวดูดซับของแข็งที่มากขึ้นมีผลต่อการเพิ่มประสิทธิภาพการดักจับแก๊สคาร์บอนไดออกไซด์ได้สูงขึ้น และการศึกษาผลของอุณหภูมิและความดันขาออกของดาวเนอร์ พบว่าอุณหภูมิที่สูงขึ้นทำให้เกิดการฟื้นฟูสภาพตัวดูดซับของแข็งที่ดีขึ้น แต่ทำให้การดูดซับแก๊สคาร์บอนไดออกไซด์ลดลงเล็กน้อย และการลดความดันที่ขาออกของดาวเนอร์ส่งผลให้เกิดความแตกต่างของความดันภายในกระบวนการ ทำให้ความเร็วแก๊สขาเข้าและแรงผลักดันในระบบเพิ่มสูงขึ้น

การจำลองพลศาสตร์ของไหลเชิงคำนวณของการคายซับคาร์บอนไดออกไซด์จากโพแทสเซียมคาร์บอเนต/แกมมา-อะลูมินาในฟลูอิไดซ์เบดดาวเนอร์โดยผลร่วมความดันและอุณหภูมิ, ศศิธร อังคณาวิศัลย์

Chulalongkorn University Theses and Dissertations (Chula ETD)

ปัจจุบันปัญหาภาวะโลกร้อนรุนแรงเพิ่มมากขึ้น ซึ่งเป็นผลมาจากการปลดปล่อยแก๊สเรือนกระจกสู่บรรยากาศเพิ่มสูงขึ้น คาร์บอนไดออกไซด์ซึ่งเป็นหนึ่งในองค์ประกอบหลักของแก๊สเรือนกระจกจะถูกปลดปล่อยออกมาจาก 3 แหล่งหลัก ซึ่งหนึ่งในนั้น คือ การผลิตไฟฟ้า และเนื่องจากความต้องการในการใช้พลังงานยังเพิ่มสูงขึ้นทำให้แนวโน้มในการปลดปล่อยคาร์บอนไดออกไซด์ยังคงเพิ่มมากขึ้น นำมาสู่การพัฒนาเทคโนโลยีในการ ดักจับคาร์บอนไดออกไซด์ การดักจับคาร์บอนไดออกไซด์โดยใช้ตัวดูดซับของแข็งเป็นหนึ่งในวิธีที่ได้รับความสนใจ ในงานวิจัยนี้จะศึกษาผลของอุณหภูมิและความดันต่อกระบวนการคายซับคาร์บอนไดออกไซด์ของตัวดูดซับของแข็งโพแทสเซียมคาร์บอเนต/แกมมา-อะลูมินาที่ผ่านการอิมเพรกเนชันด้วยตัวทำละลายมอนอเอทาโนลามีน สร้างแบบจำลองจลนพลศาสตร์และประเมินพลังงานที่ใช้ในกระบวนการคายซับ นอกจากนี้ จะศึกษากระบวนการคายซับด้วยแบบจำลองพลศาสตร์ของไหลเชิงคำนวณร่วมกับแบบจำลองสัมประสิทธิ์การชน แบบพลวัติโดยใช้ผลร่วมของความดันและอุณหภูมิ ผลที่ได้ พบว่า อุณหภูมิที่ใช้ในการคายซับมีผลเชิงบวกต่ออัตราการคายซับของตัวดูดซับที่ผ่านและไม่ผ่านกระบวนการปรับปรุง เมื่ออุณหภูมิเพิ่มขึ้น อัตราการคายซับเพิ่มสูงขึ้น ขณะที่ความดันที่ใช้ในการคายซับมีผลเชิงลบต่ออัตราการคายซับ โดยเมื่อลดความดันที่ใช้ในการคายซับ อัตราการคายซับจะเพิ่มขึ้น ซึ่งตัวดูดซับของแข็งที่ผ่านกระบวนการปรับปรุงในภาวะการคายซับที่ 200 oC ความดัน 1 บาร์ จะให้ค่าอัตราการคายซับสูงที่สุดรวมถึงใช้พลังงานในการคายซับสูงที่สุด และแบบจำลอง อาฟรามีสามารถใช้อธิบายอัตราการเกิดปฏิกิริยาการคายซับได้ นอกจากนี้ ในการจำลองกระบวนการคายซับคาร์บอนไดออกไซด์โดยใช้ผลร่วมของความดันและอุณหภูมิ พบว่า กรณีที่พิจารณาสัมประสิทธิ์การชนแบบพลวัติให้อัตราการคายซับต่ำกว่ากรณีที่ไม่พิจารณาสัมประสิทธิ์การชนแบบพลวัติ และเมื่อพิจารณาผลของอุณหภูมิต่ออัตราการคายซับที่ภาวะความดันต่ำของตัวดูดซับของแข็งที่ผ่านกระบวนการปรับปรุง พบว่า อัตราการคายซับมีปริมาณใกล้เคียงกัน

Volcanic Impact On Stratospheric Chlorine Chemistry And Perchlorate Formation: Evidence From Ice Cores, Joshua Andrew Kennedy

Electronic Theses and Dissertations

Perchlorate, suspected to be chemically formed in both the troposphere and stratosphere, has been recently measured in Arctic snow and ice cores. These comprise both discontinuous snow and ice cores from the Canadian Arctic and a continuous record of perchlorate was compiled from an analysis of Greenland ice cores. While the background perchlorate concentration typically is very low, a few spikes in concentration coinciding with deposition of volcanic sulfate were observed in the Greenland record, suggesting that perchlorate levels in the atmosphere may be impacted by volcanic eruptions. As of yet, no work has been done to investigate the connection …

A Square Channel Vanadium Phosphite Framework As A High Voltage Cathode For Li- And Na-Ion Batteries, Prashanth Sandineni, Pranal Madria, Kartik Ghosh, Amitava Choudhury

Chemistry Faculty Research & Creative Works

A vanadium phosphite compound, LiV(HPO3)2, has been synthesized using low-melting flux composed of phosphorous acid and lithium hydroxide. The crystal structure of the compound as refined using the Rietveld method matched with the previously reported unit cell parameters (space group: I42d, a = b = 10.5987(4), c = 9.9843(5) Å). It has a 3-dimensional open-framework structure with intersecting channels. Eight-membered ring square channels can be viewed along the c-axis and 6-membered ring channels along the a- and b-axis. The Li-ions are located in the six-membered ring channels exactly at the opening window to the eight-membered ring channels. The magnetic property …

Technology-Based Culturally Relevant Chemistry Education (Crce), Mercy Adoma Fosu

Electronic Theses and Dissertations

The relevance of chemistry concepts and principles remains a challenge for most students enrolled in college chemistry courses. Part of this problem is the disconnect with what students experience in their every-day lives, and how the material, specifically chemistry content is presented via textbooks, lectures, and laboratory teaching. Moreover, the teaching of general chemistry has traditionally focused on traditional, instructor-centric expository delivery of course materials, that treats students as empty vessels devoid of prior knowledge. Students prior knowledge and experiences are crucial in shaping their understanding of scientific concepts and principles. Even students with relatively low expectations for success in …

An Annual Time Series Of Weekly Size-Resolved Aerosol Properties In The Megacity Of Metro Manila, Philippines, Connor Stahl, Melliza Templonuevo Cruz, Paola Angela Bañaga, Grace Betito, Rachel A. Braun, Mojtaba Azadi Aghdam, Maria Obiminda L. Cambaliza, Genevieve Rose Lorenzo, Alexander B. Macdonald, Preciosa Corazon Pabroa, John Robin Yee, James Bernard Simpas, Armin Sorooshian

Physics Faculty Publications

Size-resolved aerosol samples were collected in Metro Manila between July 2018 and October 2019. Two Micro-Orifice Uniform Deposit Impactors (MOUDI) were deployed at Manila Observatory in Quezon City, Metro Manila with samples collected on a weekly basis for water-soluble speciation and mass quantification. Additional sets were collected for gravimetric and black carbon analysis, including during special events such as holidays. The unique aspect of the presented data is a year-long record with weekly frequency of size-resolved aerosol composition in a highly populated megacity where there is a lack of measurements. The data are suitable for research to understand the sources, …

Fluoresence Spectra Study Of Sterically Strained Isomers Of C24h14 Polycyclic Aromatic (Pahs) & Characterization Of A Bio-Sourced, Fluoresent, Ratiometric Ph Indicator With Alkaline Pka, Samar Abd Alelah

Electronic Theses and Dissertations, 2020-2023

This thesis is composed to two studies, each of which relies on recent advances in time-dependent density functional theory (TD-DFT) to accurately model fluorescence spectra. The first study focuses on evaluating the fluorescence spectrum of polycyclic aromatic hydrocarbons (PAHs) having a molecular weight of 302. Three isomers are analyzed including dibenzo[a,j]fluoranthene, dibenzo[a,k]fluoranthene and dibenzo[a,l]fluoranthene. These isomers differ in the placement of one of six aromatic rings and in the amount that each molecule deviates from planarity. The TD-DFT methods are used to compute spectra in an environment that simulates solvent (n-hexane). These computed spectra are compared to vibronically resolved experimental …

Composition, Encapsulation, And Dimensionality: A Study Of The Photophysics Brought On By Synthetic Changes In Perovskite Materials, Andrew Towers

Electronic Theses and Dissertations, 2020-2023

Perovskite materials are currently being explored as a candidate for a wide variety of optoelectronic applications with a focus on active materials for solar cell and an array of lighting applications. To optimize perovskites for optoelectronic applications, a myriad synthetic and processing techniques are used to overcome limitations in the raw materials. Presently, perovskite materials have demonstrated vast improvements as candidates for solar cell and lighting applications, though the fundamental photophysical characteristics resulting from the rapid succession of synthetic developments require further investigation. Further comprehension of the basic photophysical processes being altered by synthetic and processing changes must be achieved …

A Protocol For Metabolic Characterization Of Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes (Ips-Cm), Alisha House, Erica Fatica, Rohan Shah, Jared Stergar, Ryan Pearce, Yana Sandlers

Chemistry Faculty Publications

© 2019 The Authors Recent advances in human induced pluripotent stem cell-derived cardiomyocytes (iPSCM) field offer a novel platform for modeling cardiac metabolism, heart diseases drug candidates screening and cardiac toxicity assessments. These workflows require a fully functional characterization of iPSCMs. Here we report a step by step protocol for iPSCM metabolic characterization. The described assays cover analysis of small metabolites involved in a vital metabolic pathways.

Allylic Amination And Carbon–Carbon Double Bond Transposition Catalyzed By Cobalt(Ii) Azodioxide Complexes, Kylin A. Emhoff, Ahmed M.H. Salem, Lakshmi Balaraman, Drew M. Kingery, W. Christropher Boyd

Chemistry Faculty Publications

The unusual cobalt(II) diphenylazodioxide complex salts [Co(az)₄](PF₆)₂ and [Co(bpy)(az)₂](PF₆)₂ have been shown to catalyze the allylic amination/C–C double bond transposition reaction of 2-methyl-2-pentene with PhNHOH, with a turnover number of about 4. The mechanism is proposed to involve a nitroso-ene-like transfer of a PhNO moiety from the azodioxide ligand to the alkene, followed by reduction of the organic product to yield a cobalt(III) intermediate, which is itself reduced back to cobalt(II) by PhNHOH, regenerating PhNO. Hetero-Diels-Alder trapping experiments suggest that an “off-metal” mechanism, in which PhNO is released from the …

Synthesis, Characterization, Dna Binding, Topoisomerase Inhibition, And Apoptosis Induction Studies Of A Novel Cobalt(Iii) Complex With A Thiosemicarbazone Ligand, Stephen J. Beebe, Michael J. Celestine, Jimmie L. Bullock, Shayna Sandhaus, Jessa Faye Arca, Donald M. Cropek, Tekettay A. Ludvig, Sydney R. Foster, Jasmine S. Clark, Floyd A. Beckford, Criszcele M. Tano, Elizabeth A. Tonsel-White, Raj K. Gurung, Courtney E. Stankavich, Yuk-Ching Tse-Dinh, William L. Jarrett, Alvin A. Holder

Bioelectrics Publications

In this study, 9-anthraldehyde-N(4)-methylthiosemicarbazone (MeATSC) 1 and [Co(phen)₂(O₂CO)]Cl·6H₂O 2 (where phen = 1,10-phenanthroline) were synthesized. [Co(phen)₂(O₂CO)]Cl·6H₂O 2 was used to produce anhydrous [Co(phen)₂(H₂O)₂(NO₃)₃ 3. Subsequently, anhydrous [Co(phen)₂(H₂O)₂] (NO₃)₃ 3 was reacted with MeATSC 1 to produce [Co(phen)₂(MeATSC)](NO₃)₃·1.5H₂O·C₂ H₅OH 4. The ligand, MeATSC 1 and all complexes were characterized by elemental analysis, FT IR, UV–visible, and multinuclear NMR …

Taking Action: Intentional Inclusivity, Lesley Ann Giddings

Chemistry: Faculty Publications

No abstract provided.

Microplastic Fragment And Fiber Contamination Of Beach Sediments From Selected Sites In Virginia And North Carolina, Usa, Gabrielle Z. Dodson, A. Katrina Shotorban, Patrick G. Hatcher, Derek Waggoner, Sutapa Ghosal, Nora Noffke

OES Faculty Publications

Microplastic particles (<5 >mm) constitute a growing pollution problem within coastal environments. This study investigated the microplastic presence of estuarine and barrier island beaches in the states of Virginia and North Carolina, USA. Seventeen sediment cores were collected at four study sites and initially tested for microplastic presence by pyrolysis-gas chromatography–mass spectrometry. For the extraction, microplastic particles were first separated from the sediment using a high-density cesium chloride solution (1.88 g/mL). In a second step, an oil extraction collected the remaining microplastic particles of higher densities. Under the light microscope, the extracted microplastic particles were classified based on their morphologies …

Physical Property Improvement Of Alginate Capsule By Gellan Gum, Bacterial Cellulose And Chitosan, Aungsana Prajaksangsiri

Chulalongkorn University Theses and Dissertations (Chula ETD)

The kaffir lime oil (KLO) loaded alginate macrocapsules were prepared via a coacervation method using a coaxial glass-tube. The aims of this research were to improve the mechanical property of alginate capsule shell and to study KLO release profiles which altered by those additives. The addition of gellan gum and 2,2,6,6-tetramethylpiperidine-1-oxy radical (TEMPO)-oxidized bacterial cellulose (TOBC) in the shell-forming solution can improve the flexibility and compression strength of capsules. The size and shell thickness of capsules were in a range of 3-4 mm and 54-91 µm, respectively. Besides, the increase of TOBC amount achieved the smoother surface but increased the …

Stimuli-Responsive Gelators From Carbamoyl Sugar Derivatives And Their Responses To Metal Ions And Tetrabutylammonium Salts, Dan Wang, Anji Chen, Joedian Morris, Guijun Wang

Chemistry & Biochemistry Faculty Publications

Carbohydrate-based low molecular weight gelators (LMWGs) are interesting compounds with a variety of applications. In this research, a library of nineteen carbamate derivatives of N-acetyl-D-glucosamine were synthesized and characterized, and several derivatives were found to be effective LMWGs. They formed gels in pump oils as well as mixtures of water with ethanol or water with DMSO. The structures of the carbamoyl chains played an important role in the gelation properties, short chain aliphatic derivatives and phenyl carbamates formed gels in more solvents than certain aromatic and dimeric carbamates. The phenyl carbamate gelator was also selected for the encapsulation of …

Synthesis And Characterization Of Starburst Pseudorotaxanes And Their Metallic Derivatives, Shalini D. Kadinappulige

Masters Theses

Mechanically Interlocked Molecules (MIMs) are interlocked molecular architectures, characterized by the fact that they are linked through a mechanical bond. Catenanes, rotaxanes, molecular knots, and Borromean rings are typical examples for these molecules. Since MIMs are not connected by covalent bonds, hydrogen bonding, π- π stacking, and/or electrostatic interactions help bring the components together. Dialkyl-ammonium centers, bis(pyridinium)ethane dications, viologen species, and naphthalenediimide π-deficient groups are well known as recognition motifs for crown ethers. In the research described here, we have synthesized several pseudorotaxanes and their tricyclohexyltin metallic derivatives, based on benzobis(imidazolium) (BBI) salts as axles, in combination with the 15DN38C10 …

Development Of Supported Pd-Based Catalysts For Carbon-Carbon Cross-Coupling And Oxidation Reactions, Mrinmoy Das

Theses and Dissertations

Heterogeneous catalysts are a crucial part of chemistry used for various chemical synthesis stages, pharmaceutical, and environmental applications. The use of nanoparticles or rather nanocatalysts enhances the heterogeneous catalytic applications. Both chemical and physical methods can be used to synthesize nanocatalysts. Chemical synthesis methods require comparatively fewer instruments and can easily synthesize a large amount of nanocatalysts. Nevertheless, chemical synthesis methods require reducing agents and solvents that can be toxic or harmful materials. They often need harsh reaction conditions as well, like high temperature and pressure. On the other hand, physical synthesis methods often require complex instrument setup, but their …

Discerning The Spectroscopic Properties And Chemical Reactivity Of Bioinspired Metallocomplexes, Ashley K. Forney

Theses and Dissertations

In Nature, metalloenzymes catalyze a variety of thermodynamically demanding reactions with remarkable performance under mild, physiological conditions. This innate ability is a driving force for the development of nature inspired, synthetic analogues that are robust and can catalyze a variety of organic transformations. This work involves the successful syntheses of four coordinate, bioinspired complexes, [M^II(n-DOB)] (M = Ni, Co, and Cu; n = 12 and 13), which have been characterized by NMR, ESI-MS, UV/Vis, EPR, and CV. Spectroscopic evidence presents the generation of reactive metal-(di)oxygen species that display amphoteric reaction behavior, making these rarities among inorganic oxidants. These …

Detection Of Biomolecules Via Ocp Measurements Using Npg Electrodes, Borkat Ullah

Theses and Dissertations

In sensing application nanoporous gold (NPG) has attracted much attention. NPG is prepared by dealloying Au:Ag alloys. Characterization was done using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and cyclic voltammetry (CV). In this work, the open circuit potential (OCP) of ferricyanide, cysteine, uric acid, and ascorbic acid was measured in phosphate buffer solution (PBS) and biofouling solution containing bovine serum albumin (BSA) at pH 7.4. OCP measurement has been hindered due to biofouling and surface passivation on the metal electrodes. By the use of the NPG electrodes, electrochemical activity can be maintained. From the OCP measurement of cysteine, …

Redox-Active Porous Organic Materials For Electrochemical Energy Storage Applications, K. Shamara Weeraratne

Theses and Dissertations

As the demand for renewable energy technologies grows, so does the need for cheaper, more efficient rechargeable batteries to store the energy. While lithium-ion battery (LIBs) technology is well established, it suffers from limited lithium supplies. Furthermore, the highly toxic transition metals used in the electrodes places a huge burden on the environment. Therefore, replacing lithium with more economical sodium metal in rechargeable batteries (i.e. sodium-ion batteries, SIBs) has garnered considerable attention. Despite the fact that sodium and lithium share similar electrochemical properties, which may cause the transition from lithium to sodium easier, the larger ionic radius of Na^{+ …}

Solid Phase Extraction And High-Precision Mass Spectrometry Analysis Methods For Crassostrea Virginica Metabolome, Alyssa Darling

Theses and Dissertations

Metabolomics is the rapidly-growing field which focuses on the endpoints of biological processes, and has the capability to provide a snapshot of an organisms’ interaction with their environment on a molecular scale. The objective of the experiment herein was to develop a standard metabolic extraction technique coupled with ultrahigh-precision analytical tools to build a global metabolic pathway of the keystone species Crassostrea virginica. To achieve this, C. virginica whole-body samples were extracted using acetonitrile and methanol, then split into a dehydrated group and a diluted group. Following reversed-phase solid phase extraction (RP-SPE) of both groups, metabolites were identified using …

Preparation, Structure Elucidation, And Antioxidant Activity Of New Bis(Thiosemicarbazone) Derivatives, Hasan Yakan

Turkish Journal of Chemistry

Schiff-base-bearing new bis(thiosemicarbazone) derivatives were prepared from terephthalaldehyde and various thiosemicarbazides. FT--IR,$^{\, 1}$H NMR, $^{13}$C NMR, and UV--Vis spectroscopic methods and elemental analysis were used to elucidate the identification of the synthesized molecules. The in vitro antioxidant activity of the synthesized compounds was analysed with the 1,1-diphenyl-2-picryl hydrazyl free-radical-trapping process. The synthesized compounds exhibited lower antioxidant activity than the standard ascorbic acid. IC$_{50}$ values of the synthesized molecules measured from 3.81 $\pm $ 0.01 to 29.05 $\pm $ 0.11 $\mu$M. Among the synthesized compounds, compound 3 had the best antioxidant activity. Moreover, this study explained the structure--activity relationship of the …