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Full-Text Articles in Chemistry
Synthesis, Characterization, And Application Of Ag Nanostructures, Stephen Hudson
Synthesis, Characterization, And Application Of Ag Nanostructures, Stephen Hudson
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Noble metal nanoparticles (NPs) have been used for many centuries; however their properties were not truly scrutinized until Michael Farady's investigations in the 1850's. Advances in the field of nanotechnology over the last three decades have enabled insights into the properties of materials as their dimensions are reduced to the nanoscale. The repercussions of these insights are seen in many modern applications.
In this dissertation, properties of novel nanostructures based on Ag NPs are presented and discussed. The exceptional optical properties of Ag NPs stem from the collective oscillations of the conduction electrons known as plasmon resonances. The excitation of …
Fabrication And Optical Properties Of Noble Metal Nanostructures, Mark Kinnan
Fabrication And Optical Properties Of Noble Metal Nanostructures, Mark Kinnan
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Experimental and theoretical results are presented in Chapters 2, 3, and 4 on the effects of dielectric medium, particle size, and interparticle distance, respectively, on plasmon coupling in two-dimensional arrays of silver nanoparticles. The arrays were fabricated via the self-assembly of single crystal particles from c.a. 46 nm to 287 nm on PVP-modified glass substrates. Spin-coated poly(methylmethacrylate) layers were used to immobilize the particles and prevent their surface aggregation. Varying the thickness of the PMMA layer made it possible to change the average dielectric medium between the particles. UV-Visible spectra of different arrays were compared to the corresponding electron microscope …
Synthesis And Electrochemical Studies In Microstructured Media, Jamie Norton
Synthesis And Electrochemical Studies In Microstructured Media, Jamie Norton
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In-situ electrochemical methods involving both oxidative and reductive mediators were employed to modify the oxidation state (doping level) of PEDOT polymers in colloidal PEDOT-coated silica core-shell particles that were prepared as a dispersion encapsulated in a hydrogel matrix. The modifications of the redox states of the PEDOT coating induced a change in the absorbance characteristics. A mediated electron transfer system was employed to ferry charge from the electrodes of the cell to the isolated particles. The mediator diffuses between the electrode surface and the PEDOT-coated particles to accomplish (de)doping. The developed system was a fully self-contained and electrically driven device. …
Preparation And Characterization Of Macroporous Electrodes For Electrochemical Bioassays, Ashwin Rao
Preparation And Characterization Of Macroporous Electrodes For Electrochemical Bioassays, Ashwin Rao
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Applications such as point-of-care medical diagnosis and in-the-field biological warfare agent detection require portable bioassays which are less laborious yet cost effective. Conventional sandwich bioassays see limited use for such applications as it involves time consuming steps of reagent treatment and washings, and are restricted to use inside laboratories. We explore new platforms for sandwich bioassays required by such applications. The platform we have developed is based on electrochemical methods of detection. Flow-through three-dimensional electrodes suitable for use in electrochemical sandwich bioassays were fabricated. A composite of superporous agarose and reticulated vitreous carbon (SPA-RVC) material was used for the fabrication …