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Full-Text Articles in Physical Sciences and Mathematics
Prevention Of Iron- And Copper-Mediated Oxidative Dna Damage By Neurotransmmitters And Related Compounds: Evidence For Metal Binding As An Antioxidant Mechanism, Carla Garcia
All Theses
An array of health concerns have been attributed to oxidative DNA damage from the hydroxyl radical (*OH), and the presence of the most biologically available metals iron and copper perpetuate the production of this radical through the Fenton and Fenton-like reactions, respectively. The concentrations at which flavonol and polyphenol antioxidants prevent 50% of DNA damage (IC50) were measured using gel electrophoresis assays upon Fe(II)/H2O2- and Cu(I)/H2O2-mediated DNA damage (Chapter 2). Results show that catechol- and gallol-containing antioxidants differ greatly in preventing DNA damage by Cu(I)/H2O2, compared to Fe(II)/H2O2, behavior that was explained using electron paramagnetic resonance spectroscopy. Semiquinone and other …
The Impact Of Sulfide Mineral Weathering On The Isotopic Signatures Of Fe And Cu In Metal-Rich Streams, Ana Lourdes Gutierrez
The Impact Of Sulfide Mineral Weathering On The Isotopic Signatures Of Fe And Cu In Metal-Rich Streams, Ana Lourdes Gutierrez
Open Access Theses & Dissertations
The oxidative weathering of sulfide minerals, like pyrite, at the Earth's surface controls the formation of acid mine drainage sites as well as the Fe isotope composition of these areas and the main processes taken place. In this study, water and rock samples were collected from acidic drainages (most from abandoned mining sites) from the St. Juan Mountains in Colorado. The water samples were measured in-situ for dissolved oxygen, dissolved Fe(II), pH, and conductivity. Filtered acidified, unfiltered acidified, and Fe-oxide samples were analyzed for their metal concentrations. Ion-exchange chromatography was applied to both water and digested oxide fractions in order …
Supramolecular Organization Of Nanoparticles, Brenda M. Porta Linnell
Supramolecular Organization Of Nanoparticles, Brenda M. Porta Linnell
Open Access Theses & Dissertations
The study of supramolecular structures with nano-architectures has become an active area of research in recent years. They have the potential to generate functional materials with applications in medicine and emerging technologies. In this dissertation, the supramolecular organization of gold nanoparticles (AuNP) and other nano-scale structures such as discrete styrene-based polymers was investigated. The synthesis and characterization of metal-mediated AuNPs systems using pendant ligands on the AuNP such as 11-diethylenetriamine-undecane-1-thiol, 11-Mercapto-undecanoic acid [2-(2-amino-ethylamino)-ethyl]-amide, Bis(11-oxo-nicotinic acid, undecine)disulfide, and 11-mercaptoundecanoic acid, and using Cu(II) to mediate the formation of supramolecular AuNP systems with sizes of 200 nm ¡V 3 fÃ?m, are …
Pvd Cu Trench-Fill By Viscous Flow At High Temperatures, Zhiyuan Wu
Pvd Cu Trench-Fill By Viscous Flow At High Temperatures, Zhiyuan Wu
Legacy Theses & Dissertations (2009 - 2024)
The scaling of integrated circuits has led to new challenges in Cu interconnect fabrication. It is getting difficult to fill narrow trenches, e.g. 20 nm wide, by Cu electroplating. In this work, a high temperature PVD Cu viscous flow trench fill process was explored to overcome the difficulties of filling narrow and high aspect ratio trenches.
Nucleation, Wetting And Agglomeration Of Copper And Copper-Alloy Thin Films On Metal Liner Surfaces, Stephanie Florence Labarbera
Nucleation, Wetting And Agglomeration Of Copper And Copper-Alloy Thin Films On Metal Liner Surfaces, Stephanie Florence Labarbera
Legacy Theses & Dissertations (2009 - 2024)
One of the key challenges in fabricating narrower and higher aspect ratio interconnects using damascene technology has been achieving an ultra-thin (~2 nm) and continuous Cu seed coverage on trench sidewalls. The thin seed is prone to agglomeration because of poor Cu wetting on the Ta liner. Using in-situ conductance measurements, the effect of lowering the substrate temperature during Cu seed deposition has been studied on tantalum (Ta) and ruthenium (Ru) liner surfaces. On a Ta surface, it was found that lowering the deposition temperature to -65°C increases the nucleation rate of the Cu thin film, and reduces the minimum …
Structural And Electronic Properties Of Noble Metals On Metal Oxide Surfaces, Fei Wang
Structural And Electronic Properties Of Noble Metals On Metal Oxide Surfaces, Fei Wang
LSU Doctoral Dissertations
Noble metals on metal oxide surfaces play crucial roles in many catalysis applications. Due to extreme complexity of the interfaces and catalytic reaction processes, basic science studies of model systems are needed to guide the construction and optimization of new industrial catalysts. We have employed ultra-high vacuum techniques to investigate the morphology, electronic structure, and surface reactivations of clean metal-oxide/metal nanocluster interfaces in ideal conditions. The systems we chose are Ag/TiO2, a popular photocatalyst, and Cu/ZnO, recently a hot candidate for liquid fuel production. The main characterization techniques that we have employed include Scanning Tunneling Microscopy (STM), Photoemission Spectroscopy (PES), …
Guanidines, Amidines And Carbamides As Novel Sigma Receptor Ligands For Post-Stroke Therapeutics, Michelle Yolanda Cortes-Salva
Guanidines, Amidines And Carbamides As Novel Sigma Receptor Ligands For Post-Stroke Therapeutics, Michelle Yolanda Cortes-Salva
USF Tampa Graduate Theses and Dissertations
Stroke is the 3rd leading cause of death in the United States. For this reason, it has become our goal to find a drug that is capable of reestablishing intracellular and extracellular Ca+2 flux upon direct binding to the sigma receptor, which can be delivered easily and efficiently. Our active research focuses the development of guanidine analogues that can serve as therapeutic drugs which target sigma 1 and sigma 2 receptors having a direct effect on Ca+2 levels on the cell. The use of symmetrical guanidine analogues such as N,N'-di-o-tolyl guanidine (o-DTG) as therapeutic drugs for ischemic …