Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Life Sciences (7)
- Engineering (4)
- Kinesiology (4)
- Forest Sciences (3)
- Physics (3)
-
- Chemical Engineering (2)
- Oceanography and Atmospheric Sciences and Meteorology (2)
- Atmospheric Sciences (1)
- Biomedical (1)
- Biomedical Engineering and Bioengineering (1)
- Electrical and Computer Engineering (1)
- Environmental Chemistry (1)
- Environmental Sciences (1)
- Materials Science and Engineering (1)
- Medicine and Health Sciences (1)
- Publication Year
- Publication
- Publication Type
Articles 31 - 60 of 195
Full-Text Articles in Chemistry
Cytoviva Hyperspectral Imaging For Comparing The Uptake And Transformation Of Agnps And Ag+ In Mitochondria, Kristina Steingass
Cytoviva Hyperspectral Imaging For Comparing The Uptake And Transformation Of Agnps And Ag+ In Mitochondria, Kristina Steingass
Browse all Theses and Dissertations
Nanomaterials have attracted significant attention in the last decade, with applications in everyday products. Amongst all known nanomaterials in use, silver is the leading metal, present in 531 different types of products, owing to their unique optical, electrical, antimicrobial, and thermal properties. Though silver nanoparticles (AgNPs) come in contact regularly with the general population, there is little known about their toxicity mechanism due to limited techniques for thorough analysis. CytoViva Hyperspectral Imaging (HSI) shows potential for filling these gaps. In this study, borohydride-capped AgNPs with an approximate diameter of 10 nm were synthesized using the modified Creighton method and characterized …
Benzotriazole And Tolytriazole Analysis In Select Surface Waters Near Wilmington Air Park, Lee A. Raska
Benzotriazole And Tolytriazole Analysis In Select Surface Waters Near Wilmington Air Park, Lee A. Raska
Browse all Theses and Dissertations
Previous investigations into the presence of benzotriazole (BTZ) and corresponding analogs done in early 2019 found elevated levels near the Wilmington Air Park in Wilmington, Ohio. The analogs detected were 4-methyl-1H-benzotriazole and 5-methyl-1H-benzotriazole: known together as tolytriazole (TTZ). BTZ and TTZ are emerging environmental contaminants of concern that are often found in aircraft de-icing solutions, anti-icing solutions and detergents. The Wilmington Air Park has two facilities used to pre-treat runoff water before its subsequent release into surrounding streams. Three sites were chosen: Lytle Creek, Indian Run, and Cowan Creek. For the 2019 and 2019/2020 investigative projects, Cowan Creek was designated …
Insights On Dissolved Organic Matter Production Revealed By Removal Of Charge-Transfer Interactions In Senescent Leaf Leachates, Karl M. Meingast, Brice K. Grunert, Sarah A. Green, Evan S. Kane, Nastaran Khademimoshgenani
Insights On Dissolved Organic Matter Production Revealed By Removal Of Charge-Transfer Interactions In Senescent Leaf Leachates, Karl M. Meingast, Brice K. Grunert, Sarah A. Green, Evan S. Kane, Nastaran Khademimoshgenani
Michigan Tech Publications
Dissolved organic matter (DOM) is a critical part of the global carbon cycle. Currently, it is understood that at least a portion of the chromophoric DOM (CDOM) character can be described through an electronic interaction of charge transfer (CT) complexes. While much work has been done to understand the influence of CT on soil and aquatic reference standard DOM, little is known about the influence of CT in fresh terrestrially derived DOM. In this study, leaf litter leachates from three tree species were treated (reduced) with sodium borohydride to determine the contribution of CT on a source of fresh terrestrial …
An International Laboratory Comparison Of Dissolved Organic Matter Composition By High Resolution Mass Spectrometry: Are We Getting The Same Answer?, Jeffrey A. Hawkes, Juliana D'Andrilli, Jeffrey N. Agar, Mark P. Barrow, Stephanie M. Berg, Núria Catalán, Hongmei Chen, Rosalie K. Chu, Richard B. Cole, Thorsten Dittmar, Rémy Gavard, Gerd Gleixner, Patrick G. Hatcher, Chen He, Nancy J. Hess, Ryan H.S. Hutchins, Amna Ijaz, Hugh E. Jones, William Kew, Maryam Khaksari, Diana Catalina Palacio Lozano, Jitao Lv, Lynn Mazzoleni, Beatriz E. Noriega-Ortega, Helena Osterholz, Nikola Radoman, Shuzhen Zhang, Phoebe Zito, David C. Podgorski
An International Laboratory Comparison Of Dissolved Organic Matter Composition By High Resolution Mass Spectrometry: Are We Getting The Same Answer?, Jeffrey A. Hawkes, Juliana D'Andrilli, Jeffrey N. Agar, Mark P. Barrow, Stephanie M. Berg, Núria Catalán, Hongmei Chen, Rosalie K. Chu, Richard B. Cole, Thorsten Dittmar, Rémy Gavard, Gerd Gleixner, Patrick G. Hatcher, Chen He, Nancy J. Hess, Ryan H.S. Hutchins, Amna Ijaz, Hugh E. Jones, William Kew, Maryam Khaksari, Diana Catalina Palacio Lozano, Jitao Lv, Lynn Mazzoleni, Beatriz E. Noriega-Ortega, Helena Osterholz, Nikola Radoman, Shuzhen Zhang, Phoebe Zito, David C. Podgorski
Michigan Tech Publications
High-resolution mass spectrometry (HRMS) has become a vital tool for dissolved organic matter (DOM) characterization. The upward trend in HRMS analysis of DOM presents challenges in data comparison and interpretation among laboratories operating instruments with differing performance and user operating conditions. It is therefore essential that the community establishes metric ranges and compositional trends for data comparison with reference samples so that data can be robustly compared among research groups. To this end, four identically prepared DOM samples were each measured by 16 laboratories, using 17 commercially purchased instruments, using positive-ion and negative-ion mode electrospray ionization (ESI) HRMS analyses. The …
Role Of Structural Dynamics In Selectivity And Mechanism Of Non-Heme Fe(Ii) And 2-Oxoglutarate-Dependent Oxygenases Involved In Dna Repair, Sodiq Waheed, Rajeev Ramanan, Shobhit Chaturvedi, Nicolai Lehnert, Christopher J. Schofield, Christo Z. Christov, Tatyana Karabencheva-Christova
Role Of Structural Dynamics In Selectivity And Mechanism Of Non-Heme Fe(Ii) And 2-Oxoglutarate-Dependent Oxygenases Involved In Dna Repair, Sodiq Waheed, Rajeev Ramanan, Shobhit Chaturvedi, Nicolai Lehnert, Christopher J. Schofield, Christo Z. Christov, Tatyana Karabencheva-Christova
Michigan Tech Publications
AlkB and its human homologue AlkBH2 are Fe(II)- and 2-oxoglutarate (2OG)-dependent oxygenases that repair alkylated DNA bases occurring as a consequence of reactions with mutagenic agents. We used molecular dynamics (MD) and combined quantum mechanics/molecular mechanics (QM/MM) methods to investigate how structural dynamics influences the selectivity and mechanisms of the AlkB- and AlkBH2-catalyzed demethylation of 3-methylcytosine (m3C) in single (ssDNA) and double (dsDNA) stranded DNA. Dynamics studies reveal the importance of the flexibility in both the protein and DNA components in determining the preferences of AlkB for ssDNA and of AlkBH2 for dsDNA. Correlated motions, including of a …
Richardsite, Zn2cugas4, A New Gallium-Essential Member Of The Stannite Group From The Gem Mines Near Merelani, Tanzania, Luca Bindi, John A. Jaszczak
Richardsite, Zn2cugas4, A New Gallium-Essential Member Of The Stannite Group From The Gem Mines Near Merelani, Tanzania, Luca Bindi, John A. Jaszczak
Michigan Tech Publications
The new mineral richardsite occurs as overgrowths of small (50–400 μm) dark gray, disphenoidal crystals with no evident twinning, but epitaxically oriented on wurtzite–sphalerite crystals from the gem mines near Merelani, Lelatema Mountains, Simanjiro District, Manyara Region, Tanzania. Associated minerals also include graphite, diopside, and Ge,Ga-rich wurtzite. It is brittle, dark gray in color, and has a metallic luster. It appears dark bluish gray in reflected plane-polarized light, and is moderately bireflectant. It is distinctly anisotropic with violet to light-blue rotation tints with crossed polarizers. Reflectance percentages for Rmin and Rmax in air at the respective wavelengths are 23.5, 25.0 …
Targeting Oncogenic K-Ras And Monoamine Oxidase B Utilizing Chalcones Bearing The 3,4,5-Trimethoxyphenyl Motif, Cody Fourman
Targeting Oncogenic K-Ras And Monoamine Oxidase B Utilizing Chalcones Bearing The 3,4,5-Trimethoxyphenyl Motif, Cody Fourman
Browse all Theses and Dissertations
Oncogenic K-Ras is a driver protein found in specific cancers and was once thought to be “undruggable.” However, recent advances have suggested that mislocalizing K-Ras from the plasma membrane could be a viable strategy to target these cancers. The objective of this project was to identify a lead compound and determine a structure-activity relationship from chalcones bearing the 3,4,5-trimethoxy motif towards oncogenic K-Ras and MAO-B. This was accomplished by keeping the trimethoxy group consistent on one ring while varying the electron-donating or -withdrawing groups on the opposite ring. Previous work showed chalcones of this specific archetype exhibiting indiscriminate MAO inhibition, …
Development Of Tetrathiafulvalene Fused N-Heterocyclic Carbene Compounds, William J. Robinson Iii
Development Of Tetrathiafulvalene Fused N-Heterocyclic Carbene Compounds, William J. Robinson Iii
Browse all Theses and Dissertations
Separately, N-Heterocyclic carbene and Tetrathiafulvalene compounds show great promise for a variety of applications. N-heterocyclic carbenes exhibit desirable metal bonding characteristics which allow for modulation of the metal center via back-bonding interactions. Additionally, this creates a system of increased bonding strength creating stable complexes. Tetrathiafulvalene exhibits strong redox-active and optical characteristics. These are owed to an increased aromaticity as oxidation of the compound occurs and thus, is stable through a multitude of oxidative states. The marriage of these two functionalization creates a unique opportunity for a “cure-all” compound, able to address many problems the world faces today including, but not …
Introducing Functionality To Poly(Arylene Ether)S Via Modification Of Diphenyl Sulfone – Type Monomers, Zahida Humayun
Introducing Functionality To Poly(Arylene Ether)S Via Modification Of Diphenyl Sulfone – Type Monomers, Zahida Humayun
Browse all Theses and Dissertations
The synthesis of poly(arylene ether)s, with a pendent aryl iodide, was achieved via nucleophilic aromatic substitution (NAS) polycondensation of DI-DFDPS monomer. The platform diiodo-difluorodiphenyl sulfone monomer, DFDPS-DI (3), was prepared in one-step, via EAS chemistry. Structural characterization was provided by NMR spectroscopy, GC/MS, and elemental analysis. As “pre” approach didn’t work here, so “post” approach was used to synthesize N-heterocycle functionalized copolymers. The DI-copolymers were subjected to copper-catalyzed C-N coupling reaction with carbazole, phenoxazine, and indole and the syntheses of chromophore based copolymer were successfully carried out. A series of PAEs containing carbazole, phenoxazine, and indole substituents were synthesized and …
Quantum Chemical Pka Estimation Of Carbon Acids, Saturated Alcohols, And Ketones Via Quantitative Structure-Activity Relationships, Corey Adam Baldasare
Quantum Chemical Pka Estimation Of Carbon Acids, Saturated Alcohols, And Ketones Via Quantitative Structure-Activity Relationships, Corey Adam Baldasare
Browse all Theses and Dissertations
Acid dissociation constants, often expressed as pKa values, afford vital information with regards to molecular behavior in various environments and are of significance in fields of organic, inorganic, and medicinal chemistry. Several quantitative structure-activity relationships (QSARs) were developed that correlate experimental pKas for a given class of compounds with a descriptor(s) calculated using density functional theory at the B3LYP/6-31+G** level utilizing the CPCM solvent model. A set of carbon acids provided a good final QSAR model of experimental aqueous pKas versus ΔEH2O (R2 = 0.9647) upon removal of three aldehydes as outliers. A study of saturated alcohols offered a final …
Organic Blue Tadf Chromophore Tag For Monitoring Transfection Studies, Brandon G. Bresler
Organic Blue Tadf Chromophore Tag For Monitoring Transfection Studies, Brandon G. Bresler
Browse all Theses and Dissertations
A novel organic TADF chromophore was synthesized via a 3-step process to emit a blue fluorescent light upon excitation. The chromophore was covalently attached to a 61% isobutyryl amidated poly(ethyleneimine) (PEI-IBAm0.61) non-viral gene vector utilized in gene transfection experiments. The gene vectors are loaded with a green fluorescent protein (GFP) and are monitored via fluorescence microscopy. The addition of the blue chromophore therefore allows for the monitoring of the movements of the PEI-IBAm0.61 through the full delivery mechanism of the GFP inside the cells. This can give vital information about the overall toxicity of these non-viral gene vectors to biological …
Investigating Heterogeneous Nucleation Of Barite Using Hydrothermal Atomic Force Microscopy And Optical Microscopy, Ankita B. Gurav
Investigating Heterogeneous Nucleation Of Barite Using Hydrothermal Atomic Force Microscopy And Optical Microscopy, Ankita B. Gurav
Browse all Theses and Dissertations
In order to develop a better understanding heterogeneous nucleation of barite, barite precipitation was studied under varying experimental parameters. Hydrothermal atomic force microscopy (HAFM) and optical microscopy were used to investigate the effect of change in temperature, supersaturation and varying ratios of ions on heterogeneous nucleation of barite. In the experiments conducted at higher temperatures, the particles thus nucleated were found to display characteristic hexagonal and rhomboidal shapes. In comparing results of particle densities among different ion ratios, there is evidence suggesting that barium to sulfate ratio plays a role of promoter. Wherein, the ratios with higher [Ba2+] concentration were …
Exploring The Multiplex Detection Capabilities Of Raman Spectroscopy On Mock Street Samples Containing Illicitly Manufactured Fentanyls, Mia Laverne Williams Burnett
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. …
Antibacterial Properties Of Mussel-Inspired Polydopamine Coatings Prepared By A Simple Two-Step Shaking-Assisted Method, Pegah Kord Fooroshani, Elizabeth Polega, Kevin Thomson, Mohammad Saleh Akram Bhuiyan, Rattapol Pinnaratip, Mikhail Trought, Chito E. Kendrick, Yuesheng Gao, Kahryn Perrine, Lei Pan, Bruce P. Lee
Antibacterial Properties Of Mussel-Inspired Polydopamine Coatings Prepared By A Simple Two-Step Shaking-Assisted Method, Pegah Kord Fooroshani, Elizabeth Polega, Kevin Thomson, Mohammad Saleh Akram Bhuiyan, Rattapol Pinnaratip, Mikhail Trought, Chito E. Kendrick, Yuesheng Gao, Kahryn Perrine, Lei Pan, Bruce P. Lee
Michigan Tech Publications
A simple two-step, shaking-assisted polydopamine (PDA) coating technique was used to impart polypropylene (PP) mesh with antimicrobial properties. In this modified method, a relatively large concentration of dopamine (20 mg ml−1) was first used to create a stable PDA primer layer, while the second step utilized a significantly lower concentration of dopamine (2 mg ml−1) to promote the formation and deposition of large aggregates of PDA nanoparticles. Gentle shaking (70 rpm) was employed to increase the deposition of PDA nanoparticle aggregates and the formation of a thicker PDA coating with nano-scaled surface roughness (RMS = 110 …
Extensive Soot Compaction By Cloud Processing From Laboratory And Field Observations, Janarjan Bhandari, Swarup China, Kamal Kant Chandrakar, Greg Kinney, Will Cantrell, Raymond Shaw, Lynn Mazzoleni, Giulia Girotto, Noopur Sharma, Kyle Gorkowski, Stefania Gilardoni, Stefano Decesari, Maria Cristina Facchini, Nicola Zanca, Giulia Pavese, Francesco Esposito, Manvendra K Dubey, Allison C Aiken, Rajan K Chakrabarty, Hans Moosmüller, Timothy B Onasch, Rahul A Zaveri, Barbara V Scarnato, Paulo Fialho, Claudio Mazzoleni
Extensive Soot Compaction By Cloud Processing From Laboratory And Field Observations, Janarjan Bhandari, Swarup China, Kamal Kant Chandrakar, Greg Kinney, Will Cantrell, Raymond Shaw, Lynn Mazzoleni, Giulia Girotto, Noopur Sharma, Kyle Gorkowski, Stefania Gilardoni, Stefano Decesari, Maria Cristina Facchini, Nicola Zanca, Giulia Pavese, Francesco Esposito, Manvendra K Dubey, Allison C Aiken, Rajan K Chakrabarty, Hans Moosmüller, Timothy B Onasch, Rahul A Zaveri, Barbara V Scarnato, Paulo Fialho, Claudio Mazzoleni
Michigan Tech Publications
Soot particles form during combustion of carbonaceous materials and impact climate and air quality. When freshly emitted, they are typically fractal-like aggregates. After atmospheric aging, they can act as cloud condensation nuclei, and water condensation or evaporation restructure them to more compact aggregates, affecting their optical, aerodynamic, and surface properties. Here we survey the morphology of ambient soot particles from various locations and different environmental and aging conditions. We used electron microscopy and show extensive soot compaction after cloud processing. We further performed laboratory experiments to simulate atmospheric cloud processing under controlled conditions. We find that soot particles sampled after …
Spontaneous Selective Deposition Of Iron Oxide Nanoparticles On Graphite As Model Catalysts, Chathura De Alwis, Timothy Leftwich, Pinaki Mukherjee, Alex Denofre, Kahryn Perrine
Spontaneous Selective Deposition Of Iron Oxide Nanoparticles On Graphite As Model Catalysts, Chathura De Alwis, Timothy Leftwich, Pinaki Mukherjee, Alex Denofre, Kahryn Perrine
Michigan Tech Publications
Iron oxide nanomaterials participate in redox processes that give them ideal properties for their use as earth-abundant catalysts. Fabricating nanocatalysts for such applications requires detailed knowledge of the deposition and growth. We report the spontaneous deposition of iron oxide nanoparticles on HOPG in defect areas and on step edges from a metal precursor solution. To study the nucleation and growth of iron oxide nanoparticles, tailored defects were created on the surface of HOPG using various ion sources that serve as the target sites for iron oxide nucleation. After solution deposition and annealing, the iron oxide nanoparticles were found to nucleate …
Detecting Zn(Ii) Ions In Live Cells With Near-Infrared Fluorescent Probes., Mingxi Fang, Shuai Xia, Jianheng Bi, Travis P Wigstrom, Loredana Valenzano, Jianbo Wang, Marina Tanasova, Rudy Luck, Haiying Liu
Detecting Zn(Ii) Ions In Live Cells With Near-Infrared Fluorescent Probes., Mingxi Fang, Shuai Xia, Jianheng Bi, Travis P Wigstrom, Loredana Valenzano, Jianbo Wang, Marina Tanasova, Rudy Luck, Haiying Liu
Michigan Tech Publications
Two near-infrared fluorescent probes (A and B) containing hemicyanine structures appended to dipicolylamine (DPA), and a dipicolylamine derivative where one pyridine was substituted with pyrazine, respectively, were synthesized and tested for the identification of Zn(II) ions in live cells. In both probes, an acetyl group is attached to the phenolic oxygen atom of the hemicyanine platform to decrease the probe fluorescence background. Probe A displays sensitive fluorescence responses and binds preferentially to Zn(II) ions over other metal ions such as Cd2+ ions with a low detection limit of 0.45 nM. In contrast, the emission spectra of probe B is …
Determination Of Benzotriazole And Analog Compounds By Liquid Chromatography-Mass Spectrometry In Surface Runoff Water Samples From Wilmington Air Park, Jessica A. Wiese
Determination Of Benzotriazole And Analog Compounds By Liquid Chromatography-Mass Spectrometry In Surface Runoff Water Samples From Wilmington Air Park, Jessica A. Wiese
Browse all Theses and Dissertations
Benzotriazole (BTri) and its analog compounds are widely used in aircraft de-icing and anti-icing solutions, however their high solubility in water and resistance to biodegradation results in only their partial removal in wastewater treatment, and therefore makes them potential contaminants in watershed systems. The Wilmington Air Park in Wilmington, Ohio currently has two surface-runoff lagoons to pre-treat water containing these de-icing compounds before releasing it into nearby streams. Because the Wilmington Air Park has recently made an agreement with a major online retailer to lease over two dozen planes and open a package-sorting facility beginning in late 2019, the goal …
Silver Nanoparticles: An Effective Antibacterial Agent Against Gram-Negative Bacteria, Ashley M. Wilcox
Silver Nanoparticles: An Effective Antibacterial Agent Against Gram-Negative Bacteria, Ashley M. Wilcox
Browse all Theses and Dissertations
A fourth of the world’s population lack access to safe water, thus the need for a more effective water treatment is imperative. Interest in silver nanoparticles (AgNPs) has grown in the last decade. Unlike chlorine, AgNPs do not form disinfection by products (DBPs), making them a prime candidate for drinking water treatment. The main aim of this study was to compare the antibacterial activity of electrochemical silver nanoparticles (eAgNPs-f) of ~5 nm in diameter against well-established pathogens: Escherichia coli (E. coli), Klebsiella variicola (K. variicola), and Pseudomonas aeruginosa (P. aeruginosa) to chlorine and Ag+ for drinking water. This was achieved …
Implication Of Inorganic Nitrogen And Phosphorous Species As A Cause Of A Harmful Algal Bloom Event In Caesar Creek Lake, Ohio And Its Tributaries, Baxter Jeffrey Foskuhl
Implication Of Inorganic Nitrogen And Phosphorous Species As A Cause Of A Harmful Algal Bloom Event In Caesar Creek Lake, Ohio And Its Tributaries, Baxter Jeffrey Foskuhl
Browse all Theses and Dissertations
Agricultural runoff poses a threat to the Wilmington, Ohio municipal water supply and its source waters. A harmful algal bloom (HAB) was documented in June 2019 in Caesar Creek Lake, Waynesville, Ohio. This study seeks to establish baseline nutrient concentrations in Caesar Creek Lake (Warren County, Ohio) and its tributaries, and to identify potential non-point sources of excess nitrogen and phosphorous that contributed to the HAB event. In collaboration with the Wilmington Water Department, dissolved inorganic nitrogen DIN-[N] (sum of NH3-[N], NH4+-[N], NO2--[N], NO3--[N] concentrations), dissolved phosphorous DP-[P], particulate phosphorous PP-[P], total phosphorous TP-[P] (total sum of DP-[P] and PP-[P] …
In Vitro Uptake And Biodistribution Of Silver Nanoparticles In Vero 76 Cells, Miriam A. Crane
In Vitro Uptake And Biodistribution Of Silver Nanoparticles In Vero 76 Cells, Miriam A. Crane
Browse all Theses and Dissertations
The number of consumer products containing nanomaterials over the last eight years has increased over two-fold. Silver is one of the most commonly used materials in consumer goods nanoparticle fabrication.1 Thus, the uptake and biodistribution of silver nanoparticles (AgNPs) within mammalian cells can provide insight into their possible toxicological effects. In this study, starch-capped AgNPs of an average diameter of 9 ± 5 nm were synthesized via a bottom-up method, and characterized by Raman spectroscopy, transmission electron microscopy (TEM), inductively couple plasma optical emission spectroscopy (ICP-OES), and absorption spectroscopy. Vero 76 cells were incubated with 0.0, 0.1, 1.0, and 3.0 …
Production Of Trimethylaluminum (Me3al) With Counterfeit Refrigerant Chloromethane (R-40), Reactivity Of Me3al With Refrigerant Oils And Methods To Deactivate Me3al, Zhichao Chen, Rudy Luck
Production Of Trimethylaluminum (Me3al) With Counterfeit Refrigerant Chloromethane (R-40), Reactivity Of Me3al With Refrigerant Oils And Methods To Deactivate Me3al, Zhichao Chen, Rudy Luck
Michigan Tech Publications
Reactions between Al containing materials and counterfeit refrigerant chloromethane (R-40) were investigated under various conditions. The addition of Mg effected a reaction indicating that trimethylaluminum may have been produced in the reaction. A different study involving Al-foil, AlCl3 and chloromethane resulted in cracks detected on the Al-foil which reduced in weight by 19% and methane was detected. Studies conducted either at room temperature or at 80°C with two other genuine refrigerants, R-142b (1-chloro-1,1-difluoroethane) and R-133a (2-chloro-1,1,1-trifluoroethane) did not form organoaluminum compounds. Several commercially available refrigerant oils were subjected to Me3Al. Only polyester oil resulted in a decrease …
Metabolism-Driven High-Throughput Cancer Identification With Glut5-Specific Molecular Probes, Srinivas Kannan, Vagarshak Begoyan, Joseph Fedie, Shuai Xia, Łukasz J. Weseliński, Marina Tanasova, Smitha Rao
Metabolism-Driven High-Throughput Cancer Identification With Glut5-Specific Molecular Probes, Srinivas Kannan, Vagarshak Begoyan, Joseph Fedie, Shuai Xia, Łukasz J. Weseliński, Marina Tanasova, Smitha Rao
Michigan Tech Publications
Point-of-care applications rely on biomedical sensors to enable rapid detection with high sensitivity and selectivity. Despite advances in sensor development, there are challenges in cancer diagnostics. Detection of biomarkers, cell receptors, circulating tumor cells, gene identification, and fluorescent tagging are time-consuming due to the sample preparation and response time involved. Here, we present a novel approach to target the enhanced metabolism in breast cancers for rapid detection using fluorescent imaging. Fluorescent analogs of fructose target the fructose-specific transporter GLUT5 in breast cancers and have limited to no response from normal cells. These analogs demonstrate a marked difference in adenocarcinoma and …
The Fate And One-Dimensional Transport Of Creighton Colloidal Silver Nanoparticles Through Saturated Porous Media, Jessica M. Dagher
The Fate And One-Dimensional Transport Of Creighton Colloidal Silver Nanoparticles Through Saturated Porous Media, Jessica M. Dagher
Browse all Theses and Dissertations
With the ubiquitous burst of nanotechnology, silver nanoparticles (AgNPs) have become indispensable in numerous industrial, medicinal, and research applications. Consequently, AgNPs have been alarmingly disposed into subsurface water increasing the risk of human and environmental exposure. While mechanisms of AgNP cytotoxicity have been reported, research studies on AgNP transport in subsurface water are needed, according to U.S. Environmental Protection Agency (EPA). The main goal of this study was to investigate the environmental fate and transport of widely-used Creighton colloidal AgNPs in a laboratory transport system simulating a porous, saturated groundwater aquifer. To achieve this, a large volume of AgNPs was …
Chemical Applications Of Transition Metal Nanomaterials: Nanoscale Toughening Mechanism Of Molybdenum Disulfide-Epoxy Nanocomposites And Mammalian Toxicity Of Silver Nanoparticles, John David Ryan
Browse all Theses and Dissertations
The emerging world of nanotechnology has been of great interest within the last few decades. In this regard, nanomaterials have since been implemented in a number of commercial applications including: aerospace technology, coatings, sensors, and biomedical technology. This work aimed to elucidate upon the applications of transition metal nanomaterials in two separate experimental studies. The first of these studies involved the investigation of two-dimensional molybdenum disulfide (MoS2) nanoparticles, and their role in the toughening mechanism of epoxy composites. Two separate exfoliation techniques were implanted to target the influence surface chemistry of the nanomaterial and solvent quality had on the bulk …
Synthesis Of 5-Methyl-3-Phenyl-1,3,4-Oxadiazol-2(3h)-One Derivatives By Electrophilic Aromatic Substitution, Amanda Solis Conde
Synthesis Of 5-Methyl-3-Phenyl-1,3,4-Oxadiazol-2(3h)-One Derivatives By Electrophilic Aromatic Substitution, Amanda Solis Conde
Browse all Theses and Dissertations
An important research element in the Turnbull laboratory has been the one-pot synthesis of 5-methyl-3-phenyl-1,3,4-oxadiazol-2(3H)-one from sydnone. The present study reexamined the reaction of 5-methyl-3-phenyl-1,3,4-oxadiazol-2(3H)-one with electrophiles and optimized methods for synthesis of oxadiazolinone derivatives. Further the oxadiazolinone derivatives were reacted with electrophiles to better comprehend the donating ability of the oxadiazolinone ring system in general with the expectation that the oxadiazolinone ring system is a slightly donating system. Additionally, when the structure assignment of the oxadiazolinone derivative was ambiguous, the corresponding oxadiazolinone or it’s isomer was synthesized from the appropriate sydnone to validate or refute the suggested structure. The …
A Lc-Ms/Ms-Based Method For The Multiplex Detection Of 24 Fentanyl Analogs And Metabolites In Whole Blood At Sub Ng Ml-1 Concentrations, Kraig Edward Strayer
A Lc-Ms/Ms-Based Method For The Multiplex Detection Of 24 Fentanyl Analogs And Metabolites In Whole Blood At Sub Ng Ml-1 Concentrations, Kraig Edward Strayer
Browse all Theses and Dissertations
The United States and numerous other countries worldwide are currently experiencing a public health crisis due to the abuse of illicitly manufactured fentanyl (IMF) and its analogues. This manuscript describes the development of a liquid chromatography-tandem mass spectrometry-based method for the multiplex detection of N = 24 IMF analogues and metabolites in whole blood at concentrations as low as 0.1-0.5 ng mL-1. These available IMFs were fentanyl, norfentanyl, furanyl norfentanyl, remifentanil acid, butyryl norfentanyl, remifentanil, acetyl fentanyl, alfentanil, AH-7921, U-47700, acetyl fentanyl 4-methylphenethyl, acrylfentanyl, para-methoxyfentanyl, despropionyl fentanyl (4-ANPP), furanyl fentanyl, despropionyl para-fluorofentanyl, carfentanil, (±)-cis-3-methyl fentanyl, butyryl fentanyl, isobutyryl fentanyl, sufentanil, …
Redox-Active Silver N-Heterocyclic Carbene Complexes: A Dual Targeting Antibacterial Drug, Kotiba Malek
Redox-Active Silver N-Heterocyclic Carbene Complexes: A Dual Targeting Antibacterial Drug, Kotiba Malek
Browse all Theses and Dissertations
Bacterial resistance to current [beta]-lactam antibiotics necessitates new therapeutic approaches. Silver-based drugs offer a promising alternative because of their antibacterial properties and minimal bacterial resistance. However, many silver-based antibacterial drugs rapidly release silver ions, limiting the bioavailability of silver ions for a longer period of time. Recently, N-heterocyclic carbenes (NHC) containing silver complexes have become a popular subject of research due to their versatility and the slow release of silver ions under biological conditions. To further enhance the efficacy of silver-NHC drugs, we fused redox-active substituents such as naphthoquinone and ferrocenes to NHCs. Both naphthoquinone and ferrocenes have been shown …
Structure-Property Relationships Of N-Heterocycle Functionalized Triphenylphosphine Oxide-Based Poly (Arylene Ether)S, Luke Meyer
Browse all Theses and Dissertations
The synthesis of N-heterocycle functionalized triphenylphosphine oxide based PAEs, utilizing 3,5 difluorinated diphenyl sulfone systems was achieved. 3’-Iodo 3,5-difluorodiphenylsulfone was subjected to copper and palladium catalyzed coupling reactions with carbazole, phenothiazine, and indole. The syntheses of 3’-(9-carbazole) 3,5-difluorodiphenylsulfone, 3’-(9-phenothiazine) 3,5-difluorodiphenylsulfone, and 3’-(9-indole) 3,5-difluorodiphenylsulfone were successfully carried out. Copolymers with 4,4’ difluorotriphenylphosphine oxide, as well as 4,4’ dihydroxydiphenyl ether (DPE), as the nucleophilic partner, were prepared via standard nucleophilic aromatic substitution (NAS) polycondensataion reactions. Incorporation of the monomers containing N-heterocycle units was determined by NMR spectroscopy. All polymers displayed sufficient molecular weights (Mn) to allow for films to be cast from …
Mechanistic Insights Into The Reaction Of Chlorination Of Tryptophan Catalyzed By Tryptophan 7-Halogenase., Tatyana Karabencheva-Christova, Juan Torras, Adrian J Mulholland, Alessio Lodola, Christo Christov
Mechanistic Insights Into The Reaction Of Chlorination Of Tryptophan Catalyzed By Tryptophan 7-Halogenase., Tatyana Karabencheva-Christova, Juan Torras, Adrian J Mulholland, Alessio Lodola, Christo Christov
Michigan Tech Publications
Tryptophan 7-halogenase catalyzes chlorination of free tryptophan to 7-chlorotryptophan, which is the first step in the antibiotic pyrrolnitrin biosynthesis. Many biologically and pharmaceutically active natural products contain chlorine and thus, an understanding of the mechanism of its introduction into organic molecules is important. Whilst enzyme-catalyzed chlorination is accomplished with ease, it remains a difficult task for the chemists. Therefore, utilizing enzymes in the synthesis of chlorinated organic compounds is important, and providing atomistic mechanistic insights about the reaction mechanism of tryptophan 7-halogenase is vital and timely. In this work, we examined a mechanism for the reaction of tryptophan chlorination, performed …