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Optimization Of The Adsorption Of A Textile Dye Onto Nanoclay Using A Central Composite Design, Aydin Hassani, Murat Kiranşan, Reza Darvishi Cheshmeh Soltani, Alireza Khataee, Semra Karaca

Turkish Journal of Chemistry

The main aim of this study was to evaluate the efficacy of montmorillonite clay for the adsorption of C.I. Basic Yellow 2 (BY2) dye from aqueous media. The experimental results were processed by response surface methodology based on a central composite design (CCD). The effect of four main variables, including initial BY2 concentration, adsorbent dosage, reaction time, and temperature on the removal of BY2 was evaluated by the model. The accuracy of the model and regression coefficients was appraised by employing analysis of variance. The results demonstrated a good agreement between the predicted values obtained by the model and the …

Microwave-Assisted Regioselective [1,3]-Dipolar Cycloaddition Of 3-Methyl-2-(Substitutedbenzylidene)-5-Oxopyrazolidin-2-Ium-1-Ides To Benzothiophene 1,1-Dioxide, Yaşar Dürüst, Eda Sağirli, Akin Sağirli

Turkish Journal of Chemistry

A series of pyrazolidinium ylides was reacted with benzothiophene 1,1-dioxide to afford (3R,5S,5aS,10bS)-3-methyl-5-substitutedphenyl-2,3,5,5a-tetrahydrobenzo[4,5]thieno[3,2-c]pyrazolo[1,2-a]pyrazol-1(10bH)-one 6,6-dioxides under microwave irradiation and their structures were identified by means of spectral/physical characteristics including X-ray diffraction data and HRMS measurements.

Synthesis And Characterization Of Novel Urea And Thiourea Substitute Cyclotriphosphazene Compounds As Naked-Eye Sensors For F$^{-}$ And Cn$^{-}$ Anions, Hava Özay, Mehmet Yildirim, Özgür Özay

Turkish Journal of Chemistry

Novel hexakisurea and thiourea cyclotriphosphazene compounds (3-7) were synthesized. The structure of all compounds was identified using FT-IR $^{1}$H, $^{13}$C, and $^{31}$P NMR spectroscopy; MALDI-TOF MS; and elemental analysis. The optical sensor properties for anions of 3-7 were investigated using UV-Vis spectroscopy. It was determined that compounds 6 and 7 are spectrophotometric and naked eye sensors for F$^{-}$ and CN$^{-}$ anions, respectively. Sensor properties of these compounds for anions were investigated using UV-Vis spectroscopy. The stoichiometry of host-guest complexes was found to be 1:6.

Simultaneous Analysis Of Losartan, Its Active Metabolite, And Hydrochlorothiazide In Human Plasma By A Uplc-Ms/Ms Method, Priyanka A. Shah, Primal Sharma, Jaivik V. Shah, Mallika Sanyal, Pranav S. Shrivastav

Turkish Journal of Chemistry

A selective and sensitive ultra performance liquid chromatography-tandem mass spectrometry method was developed for the simultaneous determination of losartan (LOS), EXP-3174, which is an active metabolite LOS carboxylic acid, and hydrochlorothiazide (HCTZ) in human plasma. Solid-phase extraction was carried out on Oasis HLB cartridges with 100 $\mu $L of plasma to give an extraction recovery in the range of 88.5%-102.5% for the three analytes. Chromatography on a BEH C18 column afforded baseline separation of all the analytes within 2.4 min using 1.0% formic acid in water and acetonitrile (15:85, v/v) as the mobile phase. Quantitation was performed with multiple reaction …

Synthesis And Biological Evaluation Of A New Series Of 4-Alkoxy-2-Arylquinoline Derivatives As Potential Antituberculosis Agents, Gonca Tosun, Tayfun Arslan, Zeynep İskefi̇yeli̇, Murat Küçük, Şengül Alpay Karaoğlu, Nuretti̇n Yayli

Turkish Journal of Chemistry

Three new series of 33 quinolone compounds, 2-(2-, 3-, and 4-fluorophenyl)-4-O-alkyl(C$_{5-15})$quinolines (7a-k, 8a-k, and 9a-k), were synthesized from 2-(2-, 3-, and 4-fluorophenyl)-2,3-dihydroquinolin-4(1H)-one (4, 5, and 6) by the reaction of alkyl halides under basic conditions in DMF. The new compounds 7a-k, 8a-k, and 9a-k were synthesized from flavonones 4-6, which can be considered new precursors for quinoline synthesis through a one-step reaction. All the target compounds (7a-k, 8a-k, and 9a-k) were evaluated for their in vitro antimicrobial activity against nine test microorganisms. They showed the most activity against Mycobacterium smegmatis with minimum inhibitory concentrations (MIC) of 62.5-500 $\mu $g/mL, indicating …

Microwave-Assisted Synthesis Of Condensed 1,4-Dihydropyridines As Potential Calcium Channel Modulators, Erdem Kami̇l Özer, Mi̇yase Gözde Gündüz, Ahmed El-Khouly, Mehmet Yildirim Sara, Rahi̇me Şi̇mşek, Alper Bektaş İski̇t, Osman Ci̇hat Şafak

Turkish Journal of Chemistry

This study reports the design, synthesis, and calcium channel modulatory activity evaluation of a series of 14 novel fused 1,4-dihydropyridine derivatives. The molecular design of the compounds was based on modifications of nifedipine, which is a calcium channel blocker. The compounds were achieved by one-pot microwave-assisted reaction of 4,4-dimethyl-1,3-cyclohexanedione, 5-chlorosalicylaldehyde/3,5-dichlorosalicylaldehyde, an appropriate alkyl acetoacetate, and ammonium acetate in ethanol according to a modified Hantzsch reaction. The structures of the compounds were confirmed by spectral methods and elemental analysis. To evaluate their relaxant activities, the maximum relaxant response (E$_{\max})$ and pD$_{2}$ values of the compounds and nifedipine were determined on isolated …

Microwave-Assisted Synthesis Of Novel 8-Chloro-[1,2,4]Triazolo[4,3-$A$]Pyridine Derivatives, Linjiong Zhang, Mingyan Yang, Beizhen Hu, Zhaohui Sun, Xinghai Liu, Jianquan Weng, Chengxia Tan

Turkish Journal of Chemistry

A series of novel 1,2,4-triazolo[4,3-$a$]pyridine derivatives were synthesized from 2,3-dichloropyridine and hydrazine hydrate as starting materials by multistep reactions under microwave assistance, and their structures were characterized by $^{1}$H NMR, MS, and elemental analysis. This method provides several advantages such as high yields, facile work-up, and environmental friendliness.

Solid-Phase Total Synthesis Of Cyclic Peptide Brachystemin A And Its Immunomodulating Activity, Zafar Ali Shah, Almas Jabeen, Samreen Soomro, M.Ahmed Mesaik, M.Iqbal Choudhary, Farzana Shaheen

Turkish Journal of Chemistry

Brachystemin A (\textbf{1}) is a biologically active peptide from a Chinese traditional plant \textit{Brachystemma calycinum} D. Don. (Caryophyllaceae). The current study describes the complete solid-phase total synthesis of peptide \textbf{1} by using Kenner's sulfonamide safety-catch linker strategy. It was identified by QTOF/MS data and NMR studies. Synthetic peptide \textbf{1} was tested for its immunomodulatory effect on different inflammatory parameters, including production of inflammatory cytokines, interleukin 2 (IL-2), tumor necrosis factor-$\alpha $ (TNF-$\alpha )$, and interleukin-1$\beta $ (IL-1$\beta )$, and generation of nitric oxide (NO$^{.})$. The synthetic peptide \textbf{1} showed a moderate to low level of inhibition on the production of …

A New Series Of Cu(Ii) And Ni(Ii) Complexes Of No Bidentate 4-No$_{2}$-Benzoylhydrazones: Synthesis, Characterization, And Biological Studies, Hati̇ce Başpinar Küçük, Emel Mataraci Kara, Berna Özbek Çeli̇k

Turkish Journal of Chemistry

A series of new nickel(II) and copper(II) hydrazone complexes \textbf{1--14}, containing a bidentate NO-donor hydrazone ligand, derived from 4-nitrobenzoylhydrazide and several aliphatic and aromatic aldehydes were synthesized, and their chemical structures were confirmed by means of FT-IR, UV-Vis, $^{1}$H and $^{13}$C NMR, mass spectral data, conductance measurements, and elemental analyses. The spectral data of the newly synthesized complexes show the formation of a 1:2 [metal:ligand] ratio. The ligands and their complexes were also investigated for their possible in vitro antimicrobial activities against \textit{S. aureus}, \textit{S. epidermidis}, \textit{E. coli}, \textit{K. pneumonia}, \textit{P. aeruginosa}, \textit{P. mirabilis}, \textit{E. faecalis}, and \textit{C. albicans}. Among …

Spectrophotometric Determination Of Iron Species Using Ionic Liquid Ultrasound Assisted Dispersive Liquid--Liquid Microextraction, Alireza Bazmandegan, Ali Mohammad Haji Shabani, Sayessteh Dadfarnia, Mahboubeh Saeidi, Masoud Rohani Moghadam

Turkish Journal of Chemistry

A simple and efficient method for speciation and determination of iron in different water samples was developed. The method is based on ionic liquid ultrasound assisted dispersive liquid--liquid microextraction (IL-USA-DLLME) followed by spectrophotometric determination. Fe(II) is complexed with 2,4,6-tri(2'-pyridyl)-l,3,5-triazine (TPTZ{)}, neutralized through ion pair formation with sodium dodecyl sulfate (SDS) and extracted into 1-hexyl-3-methylimidazolium hexafluorophosphate [C$_{6}$MIM][PF$_{6}$]. Total iron amount was determined after reduction of Fe(III) to Fe(II) with hydroxylamine hydrochloride. The concentration of Fe(III) was determined from the difference of concentration of total iron and Fe(II). The important parameters such as the type and volume of the extraction solvent, pH, …

Synthesis Of Novel 1,2,4-Triazoles And Triazolo-Thiadiazines As Anticancer Agents, Thoraya Abd El-Reheem Farghaly, Magda Ahmad Abdallah, Huda Kamel Mmahmoud

Turkish Journal of Chemistry

A new series of 7-arylazo-5$H$-3-(trifluoromethyl)-6-methyl-1,2,4-triazolo-[3,4-$b$]-1,3,4-thiadiazines was prepared by reaction of 4-amino-3-trifluoromethyl-5-mercapto-1,2,4-triazoles with $N$-aryl-2-oxo-propane hydrazonoyl chloride in dioxane under reflux in the presence of triethylamine. Furthermore, Schiff bases of 4-amino-5-mercapto-1,2,4-triazole derivatives were reacted with a variety of hydrazonoyl chlorides and gave the respective hydrazonothioates. In addition, the novel \textit{bis}-(1,2,4-triazole-3-thione) was reacted with the appropriate hydrazonoyl chloride in dioxane under reflux in the presence of triethylamine to give the corresponding \textit{bis}-(1,2,4-triazolethiohydrazonoate). The structures of the new compounds were established based on elemental and spectral data. The mechanism of the studied reaction was also discussed. Moreover, some of the new products were screened …

New Tetrazolic Azo Dyes Linked To (Thio)Barbiturate And Electron-Rich Aromatics As Potential Antimicrobial Agents, Nader Noroozi Pesyan, Davoud Soleimani, Nima Hosseini Jazani

Turkish Journal of Chemistry

A series of new tetrazolic azo dyes based on (thio)barbiturate and electron-rich aromatics were synthesized in excellent yield. The electron-donor and tetrazole ring moieties were linked by a $p$-phenylazo bridge and the structural characterizations were achieved by FT IR, $^{1}$H and $^{13}$C NMR, and UV-visible spectrometry. The antibacterial activity of the synthesized compounds was tested against gram-positive and gram-negative bacterial strains, namely \textit{Acinetobacter calcoaceticus} (ATCC23055), \textit{Escherichia coli} (ATCC2592), \textit{Pseudomonas aeruginosa} (ATCC27853), and \textit{Staphylococcus aureus} (ATCC25923). As a result, potential antimicrobial effects were seen for some of the synthesized compounds.

Properties And Some In Vitro Studies Of 6-Phosphogluconate Dehydrogenase Purified From The Liver Of Chalcalburnus Tarichi, The Only Fish Living In Lake Van's Highly Alkaline Water (Ph 9.8), Muhammet Güler, Vedat Türkoğlu, Mehmet Riza Kivanç

Turkish Journal of Chemistry

In this study, some enzymology parameters and some antibiotics affecting the enzyme activity of 6-phosphogluconate dehydrogenase (6PGD) extracted from t the livers of fish from Lake Van (\textit{Chalcalburnus tarichi}) were investigated because it is an important enzyme-producing NADPH, a reductive power, protecting the cell against the oxidative agents by producing reduced glutathione. The crude enzyme solution was obtained by using the affinity chromatography method. The native molecular weight of the enzyme is $\sim $90,000 $\pm $ 3000 Da and it is composed of two subunits with identical molecular weights of $\sim $46,000 Da as exhibited on sodium dodecyl sulfate-polyacrylamide gel …

Green And Efficient Synthesis Of Novel Bispyrazoles Through A Tandem Knoevenagel And Michael Type Reaction Using Nanowire Zinc Oxide As A Powerful And Recyclable Catalyst, Khalil Eskandari, Bahador Karami, Saeed Khodabakhshi, Seyyed Jafar Hoseini

Turkish Journal of Chemistry

Zinc oxide nanowires (ZnO NWs) were prepared and characterized by scanning electron microscopy, powder X-ray diffraction, and transmission electron microscopy analyses. ZnO NWs were then employed as heterogeneous and recyclable catalyst for green synthesis of some new and known bispyrazole derivatives through a tandem Knoevenagel and Michael type addition reaction of aromatic aldehyde and pyrazolone. The synthetic method is operationally simple and affords product with high yields in short reaction times.

Synthesis And In Vitro Cytotoxic Activity Of Novel Pyrazolo[1,5-$A$]Pyrimidines And Related Schiff Bases, Ashraf Sayed Hassan, Taghrid Shoukry Hafez, Souad Abdel Meguid Osman, Mamdouh Moawad Ali

Turkish Journal of Chemistry

The reaction of 5-amino-3-(4-methoxyphenylamino)-$N$-aryl-1$H$-pyrazole-4-carboxamides \textbf{1a}--\textbf{c} with ethyl acetoacetate \textbf{2} and 2-(4-fluorobenzylidene)malononitrile \textbf{6} yielded pyrazolo[1,5-$a$]pyrimidines \textbf{5a}--\textbf{c} and \textbf{9a}--\textbf{c}, respectively. On the other hand, Schiff bases \textbf{11a}--\textbf{f} were obtained upon treatment of carboxamides \textbf{1a}--\textbf{c} with some selected aldehydes \textbf{10a }and\textbf{ b}. The newly synthesized compounds were characterized and confirmed by analytical and spectroscopic data (IR, MS, $^{1}$H NMR, and $^{13}$C NMR). Pyrazolo[1,5-$a$]pyrimidines \textbf{5a}--\textbf{c} and \textbf{9a}--\textbf{c} and Schiff bases \textbf{11b}--\textbf{f} were investigated for their cytotoxicity against four human cancer cell lines (colon HCT116, lung A549, breast MCF-7, and liver HepG2) according to SRB assay and the structure--activity relationship was discussed.

A Simple Approach To Bis-Spirocycles And Spiroindole Derivatives Via Green Methods Such As Fischer Indolization, Ring-Closing Metathesis, And Suzuki--Miyaura Cross-Coupling, Sambasivarao Kotha, Rashid Ali

Turkish Journal of Chemistry

We have developed a simple synthetic methodology for bis-spirocycles and spiroindole derivatives starting with a commercially available 6-bromo-2-tetralone. Here, we have used Fischer indolization, ring-closing metathesis, and Suzuki--Miyaura cross-coupling as key steps to assemble a variety of spirocyclic frameworks. The methodology developed here is simple and it may be useful to prepare various spirocycles containing indole moiety.

Synthesis, Characterization, And Microwave-Assisted Catalytic Activity In Heck, Suzuki, Sonogashira, And Buchwald-Hartwig Cross-Coupling Reactions Of Novel Benzimidazole Salts Bearing N-Phthalimidoethyl And Benzyl Moieties, Hasan Küçükbay, Ülkü Yilmaz, Kemal Yavuz, Nesri̇n Buğday

Turkish Journal of Chemistry

Five novel benzimidazole salts (1-5) having N-phthalimidoethyl and 4-substituted benzyl were synthesized and identified by $^{1}$H NMR, $^{13}$C NMR, and IR spectroscopic methods and microanalysis. A mixture of the benzimidazole salts (1-5), Pd(OAc)$_{2}$, and K$_{2}$CO$_{3}$ in DMF-H$_{2}$O catalyzed, in high yield, the Suzuki-Miyaura and the Heck-Mizoroki cross-coupling reactions assisted by microwave irradiation in 5 min. The novel benzimidazole salts (1-5), Pd(OAc)$_{2}$, Cs$_{2}$CO$_{3}$, PEG, and Cu nanoparticles catalyzed, in high yield, the Sonogashira coupling reaction promoted by microwave irradiation in 10 min. The same benzimidazole salts (1-5), Pd(OAc)$_{2}$, Cs$_{2}$CO$_{3}$, and TBAB catalyzed, in moderate or low yield, the Buchwald-Hartwig reaction assisted …

Electrospun Titanium Dioxide And Silicon Composite Nanofibers For Advanced Lithium Ion Batteries, Kathleen Mccormac

College of Graduate Studies: Theses & Dissertations

A unique electrospinning method was implemented to fabricate composite nanofibers for lithium ion battery applications. The composite nanofibers were made of amorphous carbon, rutile phase TiO₂, and cubic phase Si nanoparticles. Sulfur was utilized as a template to form void structures within the TiO₂ nanofiber matrix. This provides the desired space for the Si expansion during the lithiation process. Phase, structure, composition, and morphology of the nanofibers were characterized using Raman spectroscopy, SEM, EDS, TGA, and powder XRD. Carbonized TiO₂ nanofibers showed a low but stable specific capacity. Si Nanoparticles demonstrated an initially high but fast …

Total Synthesis Of Biologically Active Natural And Unnatural Products, Julia Heimberger

College of Graduate Studies: Theses & Dissertations

Herbarin A and B were isolated from the fungal strains of Cladosporium herbarum found in marine sponges Aplysina aerophoba and Callyspongia aerizusa. Total synthesis of Herbarin A and B was achieved by carrying out a multi-step synthesis approach, and the antioxidant properties were evaluated using FRAP assay. Toxicity of these compounds was determined using a zebrafish embryo model. Furthermore, synthesis of C-6 alkyl-azaarene derivatives of nucleosides by Csp3-H bond functionalization were investigated. Effective incorporation of 2-methylazaarene moiety at the C-6 position of the protected inosine nucleoside provided a new class of compounds with anticipated enhanced biological activity.

Reference Material Development For Paralytic Shellfish Poisoning Toxins And Associated Analytical Applications, Stephen Burrell

Doctoral

Food poisoning incidences relating to marine biotoxins are a global phenomenon and have the potential to severely impact the aquaculture industry. As a result, and as a legislative requirement in the European Union (EU), many countries have implemented monitoring programmes for these compounds but their success relies on the availability of certain quality assurance tools, two of which are reference materials (RMs) and proficiency testing. The limited amounts of RMs, in particular matrix certified reference materials (CRMs) for paralytic shellfish poisoning (PSP) toxins has been a limiting factor in the implementation of alternatives to the mouse bioassay for routine monitoring …

Temperature And Ph Responsive Microfibers For Controllable And Variable Ibuprofen Delivery, Toan Tran, Mariana Hernandez, Dhruvil Patel, Ji Wu

Chemistry: Faculty Publications (1990-2023)

Electrospun microfibers (MFs) composed of pH and temperature responsive polymers can be used for controllable and variable delivery of ibuprofen. First, electrospinning technique was employed to prepare poly(ε-caprolactone) (PCL) and poly(N-isopropylacrylamide-co-methacrylic acid) (pNIPAM-co-MAA) MFs containing ibuprofen. It was found that drug release rates from PCL MFs cannot be significantly varied by either temperature (22–40°C) or pH values (1.7–7.4). In contrast, the ibuprofen (IP) diffusion rates from pNIPAM-co-MAA MFs were very sensitive to changes in both temperature and pH. The IP release from pNIPAM-co-MAA MFs was highly linear and controllable when the temperature was above the lower critical solution temperature (LCST) …

Constitutive Activity In Orphan G Protein Coupled Receptors, Adam Lee Martin

Doctoral Dissertations

"The goal of this research was to use a distal signaling pathway analysis to evaluate the extent of agonist independent constitutive signaling among orphan class-A G protein coupled receptors (GPCRs). These receptors translate extracellular signals via conformational change into intracellular activation of different G proteins and subsequent second messenger synthesis. These small molecules regulate cellular biochemistry, eventually leading to nuclear signaling that results in changes in gene expression. Some GPCRs are capable of signaling in the absence of an activating ligand, a phenomenon called constitutive activity that is inhibited via an "inverse-agonist". The use of cAMP dependent Luciferase expression is …

Synthesis Of Benzofused-P-Indolequinones From 1,4-Naphthoquinone And Selective N-Debenzylation By Dess-Martin Periodinane, Quang Huynh Luu

Open Access Theses & Dissertations

p-Indolequinones are important heterocycles since they display interesting bioactivities such as anticancer activities as well as the ability to trigger drug release in drug targeting research. Additionally, they are also useful in precursors for the synThesis of bioactive compounds. Over decades, many methodologies have been investigated for the synThesis of p-indolequinones. Among those, cyclization of quinones plays an important role in convenient synThesis of these compounds. However, the great majority of these methods only describe quinones as electrophiles in cyclization. In our research, we found an intramolecular nucleophilic attack of quinone to an in-situ generated carbonyl group and developed a …

Investigation Of The Natural Degradation Of Selected Endocrine Disrupting Compounds In Wastewater, Toni Carrick

Open Access Theses & Dissertations

Endocrine disrupting compounds (EDCs) are a class of compounds that are of concern for their potentially adverse effects on fish, wildlife, and humans. They can cause developmental and reproductive anomalies at concentrations in the low ppb to ppt levels. Studies have shown the primary route of exposure of EDCs within the environment is through the discharge of effluent wastewater. Removal efficiencies of wastewater treatment plants have been studied extensively, however, in rural or developing areas, which often lack secondary or tertiary wastewater treatment, little is known about the stability of these compounds and the rate at which they degrade in …

Total Synthesis Of Syringolides 1 And 2, Sudhakar Kalagara

Open Access Theses & Dissertations

The total synthesis of Syringolides is described. The synthetic pathway was designed in order to synthesize Syringolides in high yields using inexpensive starting materials. The synthesis strategy features a preparation of the linear tricarbonyl compound followed by intramolecular cyclization. The linear precursor is divided into two fragments, β-keto acid and protected D-xylulose, which are the key fragments and were synthesized from α,β-unsaturated compound followed by asymmetric dihydroxylation. The α,β-unsaturated compound was efficiently prepared by a Wittig reaction between aldehyde and ylide fragments. The butenolide derivative was also achieved by the Knoevenagel condensation of the tricarbonyl compound.

Transition Metal Carbide (Tmc) Novel Materials For Novel Catalytic Applications, Svetlana Lagoykina

Open Access Theses & Dissertations

Transition metal carbides (TMC) constitute a diverse class of materials and traditionally have many technological applications. TMC became a subject of extensive research since 1973, when their platinum -like properties were discovered. They demonstrated high catalytical activity and selectivity in a variety of chemical reaction and have potential for some novel catalytic application.

This research is an effort to design new high effective, selective and stable bimetal or alkali promoted TMC catalyst. After extensive theoretical research a wide range of TMC, including bimetal and alkali promoted carbides, were synthesized by different methods. All solids were characterized by XRD and microscopy. …

Versatility Of N-Peptidyl And N-Glycopeptidyl Nitroindolines For The Formation Of Peptide/Glycopeptide Acids, Amides, And Thioesters, Luis Alfonso Barrera

Open Access Theses & Dissertations

N-acyl-7-nitroindolines are photoreactive compounds that are known to acylate a number of nucleophiles in inert aprotic solvents under neutral conditions when illuminated at 350 nm. We have assembled a MUC1-derived peptide and Tn or STn-containing MUC1 glycopeptides with a C-terminal photoreactive 7-nitroindoline linker attached to Sieber amide resin by solid phase peptide synThesis using the Fmoc strategy. This type of construction allows for the cleavage of fully protected photoreactive peptides/glycopeptides from the resin with dilute trifluoroacetic acid, or for the direct photorelease of protected peptide/glycopeptide derivatives. Here we demonstrate that N-peptidyl and N-glycopeptidyl 7-nitrindolines can be photochemically converted into their …

Characterization Of Kendex® 0834 (Heavy Resins) & Kendex® 0897 (Light Resins), Victor Correa

Open Access Theses & Dissertations

Characterization of crude oil and some of its refined products has always been a challenge in the refining industry. This is mainly due to the high molecular complexity of crude oil. In this research, Heavy and Light Resins extracted from Penn Grade crude oil were analyzed with a wide variety of techniques, ranging from X-Ray Diffraction, Electron Microscopy, Fourier Transformed Infrared, C-13 Nuclear Magnetic Resonance, and chromatographic methods. An asphaltene extraction protocol was performed on both products. Only the Heavy Resin sample yielded a low amount of asphaltene. Results show that both Resins have a high degree of carbon branching, …

Transition States And Modeling For Co9s8/Mos2 Catalysis, Gabriel Angel Gonzalez

Open Access Theses & Dissertations

Transition state computational studies of the sulfur removal from dibenzothiophene (DBT) molecule have herein been performed considering the Co9S8/MoS2 interface existing on unsupported Co/MoS2 catalysts. The linear synchronous transit (LST) and quadratic synchronous transit (QST) methods integrated in a density functional theory (DFT) program such as Dmol3 were used for the calculations of energy barriers of the transition states. Three different configurations present on the Co9S8/MoS2 interface have been envisaged as possible catalytic sites: sulfur-sulfur (S, S) sites, and molybdenum-sulfur (Mo, S) and molybdenum-molybdenum (Mo, Mo) edge sites. This study revealed that the (Mo, Mo) edge site is the most …

Role Of Small Molecules In Rescuing Protein Folding Under Oxidative Stress, Mahmoud Fawzi Megahed Helal Khalil

Open Access Theses & Dissertations

Increased levels of nitrosative stress intracellularly within the endoplasmic reticulum is a key factor involvled in the pathogenesis of both Parkinson's (PD) and Alzheimer's (AD) diseases. Previous in-vitro studies in our lab showed that increased levels of nitrosative stress lead to aggregation of misfolded proteins and formation of Lewy Bodies, the main biomarker of PD and AD diseases. Although this was mainly through nitrosylation of Protein Disulfide Isomerase (PDI), the chief endoplasmic reticulum (ER) resident oxidoreductase chaperone responsible for maturation of disulfide-bond-containing proteins, we demonstrate in this project that increased levels of nitrosative stress has an additional direct effect on …