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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
161

Photochemical Synthesis of Mono and Bimetallic Nanoparticles and Their Use in Catalysis

Pardoe, Andrea 04 May 2011 (has links)
Nanomaterials have become a popular topic of research over the years because of their many important applications. It can be a challenge to stabilize the particles at a nanometer size, while having control over their surface features. Copper nanoparticles were synthesized photochemically using a photogenerated radical allowing spatial and temporal control over their formation. The synthesis was affected by the stabilizers used, which changed the size, dispersity, rate of formation, and oxidation rate. Copper nanoparticles suffer from their fast oxidation in air, so copper-silver bimetallic nanoparticles were synthesized in attempts to overcome the oxidation of copper nanoparticles. Bimetallic nanoparticles were synthesized, but preventing the oxidation of the copper nanoparticles proved difficult. One important application of nanoparticles that was explored here is in catalyzing organic reactions. Because of the fast oxidation of copper nanoparticles, silver nanoparticles were synthesized photochemically on different supports including TiO2 and hydrotalcite (HTC). Their catalytic efficiency was tested using alcohol oxidations. Different silver nanoparticle shapes (decahedra and plates) were compared with the spheres to see the different catalytic efficiencies.
162

Silver Nanoparticle Controlled Synthesis and Implications in Spectroscopy, Biomedical and Optoelectronics Applications

Stamplecoskie, Kevin 14 May 2013 (has links)
This thesis describes the photochemical synthesis of silver nano particles, several ways to make these particles as well as control the size and shape of the colloidal particles. Understanding the primary reactions in photochemical nanoparticle formation has lead to important contributions to the overall mechanism of metal nanoparticle synthesis. The size and shape control of the particles is shown to have important implications for the Raman spectrum of surface bound molecules. The particles have also been used in antibacterial properties where it was shown that silver nanoparticles are more antibacterial than the corresponding silver cation, while remaining non-toxic to several common cell lines. The particles were also shown to have some interesting properties that can be exploited in lithography and optoelectronics.
163

Copper, silver, and gold etching with H₂ and CH₄ based plasmas

Choi, Tae-Seop 12 January 2015 (has links)
This thesis describes investigations on Cu, Ag, and Au subtractive etching by H₂ and CH₄ plasmas below room temperature. Both blanket film of Cu, Ag, and Au etching and patterning studies were performed for the applications of these metals as interconnects in electronic devices and photonic devices to replace current Damascene process. The nm scale Cu patterning in H₂ plasma was demonstrated by etching Ta/Cu/Ta stacks. Also, Ag and Au etching was feasible in H₂ plasma unlike other transition metals such as Ti, Ta, Ni, Cr, Al, and Pt indicating the etching chemistry based on the similar electronic structures of group 11 metals plays important role. In addition, employing CH₄ plasma allowed the use of photoresist mask and patterned Cu, Ag, and Au with high selectivity. The overall etch mechanism is the combination of chemical reactions and physical (photon and ion) bombardment in H₂ and CH₄ plasma. However, the Cu etching mechanism is more dependent on the chemistry while Ag and Au patterning were dominated by physical bombardment. Finally, the direction for future work including further mechanistic study and process optimization is suggested.
164

Synthesis, annealing strategies and in-situ characterization of thermally stable composite thin Pd/Ag alloy membranes for hydrogen separation

Ayturk, Mahmut Engin. January 2007 (has links)
Thesis (Ph.D.)--Worcester Polytechnic Institute. / Keywords: composite Pd and Pd/Ag membranes, alloying, Pd/Ag barrier, intermetallic diffusion, bi-metal multi-layer BMML deposition, electroless plating kinetics, high temperature x-ray diffraction, aluminum hydroxide surface grading, porous sintered metal supports, hydrogen separation. Includes bibliographical references (leaves 279-296 ).
165

Investigation of reactions of complex epoxides on silver(110) a combined experimental and theoretical study /

Lukaski, Adrienne Claire. January 2009 (has links)
Thesis (Ph.D.)--University of Delaware, 2008. / Principal faculty advisor: Mark A. Barteau, Dept. of Chemical Engineering. Includes bibliographical references.
166

The treatment of a gold-silver-copper ore by the Argo process

Heck, Elmer Cooper. Brown, Josephus Jarvis. January 1905 (has links) (PDF)
Thesis (B.S.)--University of Missouri, School of Mines and Metallurgy, 1905. / The entire thesis text is included in file. Typescript. Title from title screen of thesis/dissertation PDF file (viewed November 18, 2008)
167

Syntheses, characterization and photophysics of polynuclear copper (I) and silver (I) complexes containing monoynyl, diynyl and chalcogen-type ligands /

Lam, Chi-ho, Aaron. January 2000 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2000. / Includes bibliographical references (leaves 250-279).
168

Investigation of silver based catalysts for ethylene epoxidation high throughput studies and characterization /

Dellamorte, Joseph C. January 2009 (has links)
Thesis (Ph.D.)--University of Delaware, 2009. / Principal faculty advisors: Mark A. Barteau and Jochen A. Lauterbach, Dept. of Chemical Engineering.. Includes bibliographical references.
169

The chloride volatilization of silver and lead from zinc concentrate

Barrett, Edward P. January 1924 (has links) (PDF)
Thesis (Professional Degree)--University of Missouri, School of Mines and Metallurgy, 1924. / The entire thesis text is included in file. Typescript. Illustrated by author. Title from title screen of thesis/dissertation PDF file (viewed June 4, 2009) Includes bibliographical references.
170

Academisk afhandling om Sahla Silfvervärks bergs-frälse

Berch, Krister Bellander, Johan Theodor January 1900 (has links)
Uppsala universitet, 1781, Thesis (doctoral). / Goldsmiths'-Kress no. 12138.0-2. - OCLC, 24258608. - Reproduction of original from Kress Library of Business and Economics, Harvard University.

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