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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.
431

Development and Characterization of Low Cost Tungsten Disulfide Ink for Ink-jet Printing

Mayersky, Joshua 21 September 2018 (has links)
No description available.
432

Design, Simulation and Physical Characterization of 3D Photonic Crystal Woodpile Structures for High Efficacy Incandescent Thermal Emission

SRIDHAR, SUPRIYA LALAPET 22 September 2008 (has links)
No description available.
433

Study of the Pulsed Electrochemical Micromachining of Ultra High Aspect Ratio Micro Tools

Mathew, Ronnie A., M.S. 20 April 2011 (has links)
No description available.
434

MODELING AND TESTING OF THE INTERFACIAL STRESS STATE OF A 316L STAINLESS STEEL CLAD TUNGSTEN COMPOSITE USING PUSH-OUT TESTING

RUTHERFORD, ROBERT WESLEY 11 October 2001 (has links)
No description available.
435

Full and half sandwich compounds of dimolybdenum and ditungsten

Hollandsworth, Carl B. 12 October 2004 (has links)
No description available.
436

The Effects of Tool Texture on Tool Wear in Friction Stir Welding of X-70 Steel

Michael, Eff 31 August 2012 (has links)
No description available.
437

The Effects of Tool Texture on Tool Wear in Friction Stir Welding of X-70 Steel

Eff, Michael 20 June 2012 (has links)
No description available.
438

Characterization of tungsten-silicide for gate level interconnections of MOS VLSI circuts /

Sabi, Babak January 1984 (has links)
No description available.
439

Effect of tungsten on nitrate and nitrite reductases in Azospirillum brasilense SP 7

Chauret, Christian January 1990 (has links)
No description available.
440

Effect of Phase Composition of Tungsten Carbide on its Catalytic Activity for Toluene Hydrogenation

Rane, Aditya 20 October 2021 (has links) (PDF)
Commercially important hydrogenation reactions make use of precious noble metal catalysts which are becoming increasingly scarce, and the search for capable alternative catalysts prevails. Transition metal carbides of group IV-VI metals show similar catalytic behavior to platinum and are $103/kg lower in price than the precious metal catalysts. Tungsten carbide, studied in this work, can form in different stoichiometries and phase compositions depending upon synthesis methods. Synthesis of high surface area tungsten carbide with control over its phase composition remains a challenge currently. In this work, the novel isothermal synthesis method of tungsten carbide (WC, W2C) in a CH4/H2 carburization atmosphere with synthesis temperature and presence or absence of a silica support in the catalyst precursor (WO3) as process variables was investigated. The amounts of CO and H2O formed during synthesis corresponded to the amount of oxygen in the WO3 precursor. The catalysts were further characterized by X-ray diffraction to determine phase composition and crystallite size, by scanning electron microscopy to determine morphology, and by CO chemisorption to determine metallic surface area. X-ray diffraction analysis indicated the carbide catalysts to contain W2C, WC, and metallic W phases. The use of a silica-supported precursor favored the formation of a nearly phase pure, high surface area W2C rich catalyst whereas high synthesis temperature and absence of silica precursor favored formation of a low surface area WC rich catalyst. Further, the catalysts were tested for steady state activity at a W/F (weight catalyst/toluene feed rate) of 0.20-0.30 h-1, addition of H2 to a total pressure of 21 bar absolute and 250 °C, and the effect of phase composition and surface area on the activity was studied. This work resulted in the successful synthesis of 4 tungsten carbide catalysts with varying phase compositions and surface areas and correlation of their compositions and surface areas with their corresponding toluene hydrogenation activities.

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