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1	Novel Copper Loaded Core-shell Silica Nanoparticles With Improved Copper Bioavailability Synthesis, Characterization And Study Of Antibacterial Properties Maniprasad, Pavithra 01 January 2011 (has links) A novel core-shell silica based antimicrobial nanoparticle was synthesized. The Stöber silica shell has been engineered to accommodate copper. Synthesis of the core-shell Cu-silica nanoparticle (C-S CuSiNP) involves preparation of base-hydrolyzed Stöber silica “seed” particles first, followed by the acid-catalyzed seeded growth of the Cu-silica shell layer around the core. Scanning electron microscopy and transmission electron microscopy showed monodispersed, spherical shaped nanoparticles with smooth surface morphology. Characterization of particle size distribution in solution by the Dynamic Light Scattering (DLS) technique was fairly consistent with the electron microscopy results. Loading of Cu to nanoparticles was confirmed by the SEM-Energy Dispersive X-Ray Spectroscopy (EDS) and Atomic Absorption Spectroscopy (AAS). Antibacterial efficacy of C-S CuSiNP was evaluated against E.coli and B.subtilis using Cu hydroxide (“Insoluble” Cu compound) and copper sulfate as positive control and silica “seed” particles (without Cu loading) as negative control. Minimum Inhibitory Concentration (MIC) of C-S CuSiNP was evaluated by measuring the fluorescent intensity of resorufin to determine the decrease in viable cells with increase in copper concentration in C-S CuSiNP. The MIC value of C-S CuSiNP against both E.coli and B.subtilis was estimated to be 4.9 ppm. Bac-light fluorescence microscopy based assay was used to count relative population of the live and dead bacteria cells. Antibacterial study clearly shows that C-S CuSiNP is more effective than insoluble Cu hydroxide particles and copper sulfate at equivalent metallic Cu concentration, suggesting more soluble Cu in C-S CuSiNP material due to its coreshell design. Core-Shell nanoparticle Copper loaded silica Antibacterial Sol-Gel Copper Biocide. Molecular Biology
2	Synthesis and Characterization of Reactive Core-Shell Nanoparticles Schwarb, Ryan Evan 11 May 2012 (has links) No description available. Chemical Engineering Chemistry Engineering Materials Science Nanoscience Nanotechnology Polymer Chemistry reactive nanoparticles reactive core-shell nanoparticles nanoparticle synthesis nanoparticle characterization nanomaterial characterization monolayer coated nanoparticles AFM
3	Two dimensional materials, nanoparticles and their heterostructures for nanoelectronics and spintronics / Matériaux bidimensionnels, nanoparticules et leurs hétérostructures pour la nanoélectronique et l’électronique de spin Mouafo Notemgnou, Louis Donald 04 March 2019 (has links) Cette thèse porte sur l’étude du transport de charge et de spin dans les nanostructures 0D, 2D et les hétérostructures 2D-0D de Van der Waals (h-VdW). Les nanocristaux pérovskite de La0.67Sr0.33MnO3 ont révélé des magnétorésistances (MR) exceptionnelles à basse température résultant de l’aimantation de leur coquille indépendamment du coeur ferromagnétique. Les transistors à effet de champ à base de MoSe2 ont permis d’élucider les mécanismes d’injection de charge à l’interface metal/semiconducteur 2D. Une méthode de fabrication des h-VdW adaptés à l’électronique à un électron est rapportée et basée sur la croissance d’amas d’Al auto-organisés à la surface du graphene et du MoS2. La transparence des matériaux 2D au champ électrique permet de moduler efficacement l’état électrique des amas par la tension de grille arrière donnant lieu aux fonctionnalités de logique à un électron. Les dispositifs à base de graphene présentent des MR attribuées aux effets magnéto-Coulomb anisotropiques. / This thesis investigates the charge and spin transport processes in 0D, 2D nanostructures and 2D-0D Van der Waals heterostructures (VdWh). The La0.67Sr0.33MnO3 perovskite nanocrystals reveal exceptional magnetoresistances (MR) at low temperature driven by their paramagnetic shell magnetization independently of their ferromagnetic core. A detailed study of MoSe2 field effect transistors enables to elucidate a complete map of the charge injection mechanisms at the metal/MoSe2 interface. An alternative approach is reported for fabricating 2D-0D VdWh suitable for single electron electronics involving the growth of self-assembled Al nanoclusters over the graphene and MoS2 surfaces. The transparency the 2D materials to the vertical electric field enables efficient modulation of the electric state of the supported Al clusters resulting to single electron logic functionalities. The devices consisting of graphene exhibit MR attributed to the magneto-Coulomb effect. Transport de charge Transistor à effet de champ Nanoparticule coeur-coquille Blocage de Coulomb Transistor à électron unique Effet magnéto-Coulomb Transport de spin Graphène Hétérostructures de van der Waals Magnétisme Magnétorésistance Pérovskites Charge transport Field effect transistor Core-shell nanoparticle Coulomb blockade Single electron transistor Magneto-Coulomb effect Spin transport Graphene Transition metal dichalcogenide Van der Waals heterostructures Magnetism Magnetoresistance Perovskites 530 537.6 620.5

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