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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.
101

Equilibria in hydrogenation of esters and indoles

Burks, Robert E. January 1947 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1947. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 78-79).
102

Regio and chemo selective hydrogenation by palladium nanoparticles embedded in polyelectrolyte films

Bhattacharjee, Somnath. January 2008 (has links)
Thesis (Ph. D.)--Michigan State University. Chemistry, 2008. / Title from PDF t.p. (Proquest, viewed on Aug. 17, 2009) Includes bibliographical references. Also issued in print.
103

Characterization and investigation of molybdenum carbides on activated carbon as hydrogenation catalysts

Clark, Christopher H. January 2005 (has links)
Thesis (M.S.)--West Virginia University, 2005. / Title from document title page. Document formatted into pages; contains viii, 76 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 54-57).
104

The catalytic activity of metalized silica gels ...

Morris, Vlon Neilan, Reyerson, Lloyd Hilton, January 1900 (has links)
Thesis (Ph. D.)--University of Minnesota, 1926. / Cover title. Vita. "By Vlon N. Morris and L.H. Reyerson." Description based on print version record.
105

Methanol synthesis from CO2/H2 over Pd-promoted Cu/ZnO/A12)3 catalysts

Sahibzada, Mortaza January 1995 (has links)
No description available.
106

Modification of Graphene Properties: Electron Induced Reversible Hydrogenation, Oxidative Etching and Layer-by-layer Thinning

Jones, Jason David 05 1900 (has links)
In this dissertation, I present the mechanism of graphene hydrogenation via three different electron sources: scanning electron microscopy, e-beam irradiation and H2 and He plasma irradiation. in each case, hydrogenation occurs due to electron impact fragmentation of adsorbed water vapor from the sample preparation process. in the proposed model, secondary and backscattered electrons generated from incident electron interactions with the underlying silicon substrate are responsible for the dissociation of water vapor. Chemisorbed H species from the dissociation are responsible for converting graphene into hydrogenated graphene, graphane. These results may lead to higher quality graphane films having a larger band gap than currently reported. in addition, the dissertation presents a novel and scalable method of controllably removing single atomic planes from multi-layer graphene using electron irradiation from an intense He plasma under a positive sample bias. As the electronic properties or multi-layer graphene are highly dependent on the number of layers, n, reducing n in certain regions has many benefits. for example, a mask in conjunction with this thinning method could be used for device applications.
107

Investigating Catalytic Selectivity of Nanoparticles encapsulated in MOFs:

Ren, Chenhao January 2021 (has links)
Thesis advisor: Chia-kuang Tsung / Thesis advisor: Dunwei Wang / Coating porous materials is a potential pathway to improve Catalytic performance of heterogeneous catalysts. The unique properties of Metal organic frameworks (MOFs) like huge surface area, long range order and high tenability make them promising coating materials. However, two traditional MOF encapsulation methods have their own issues. Herein, we synthesized Pt/Pd metal nanoparticles @UiO-66-NH2 via a one-pot in situ method which has good control of nanoparticles size while avoids the introduction of capping agent. The catalytic performance of synthesized Pt@UiO-66-NH2 is tested via selective hydrogenation of Crotonaldehyde. And the selectivity of our desired product achieves 70.42% which is much higher than merchant Pt catalysts. A step further, we used linker exchange to replace the original NH2-BDC linker of which amine group plays an important role in the coating process. After linker exchanging, the significant decreasing in selectivity of our target product demonstrates that the interaction between Pt and amine group does have some positive impacts on their catalytic performance. We hope our research could provide some insights of the MOFs and nanoparticles interface and help rational design of catalysts with high performance. / Thesis (MS) — Boston College, 2021. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.
108

The synthesis of nitrogen doped carbon spheres as supports for palladium catalysts in the hydrogenation of cinnamaldehyde

Manikai, Sibongile Mary-Anne January 2016 (has links)
A thesis submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy in Chemistry. Johannesburg, 2015. / The selective hydrogenation of cinnamaldehyde (CALD), an α,β-unsaturated aldehyde, at the carbonyl (C=O) and olefinic (C=C) groups is an important reaction since its products mainly cinnamyl alcohol (CA) and hydrocinnamaldehyde (HCALD) are important intermediates for the production of many chemicals in a wide range of industries (pharmaceuticals, flavouring, agrochemicals, perfume). In this study the synthesis of nitrogen doped carbon spheres (NCSs) as catalyst supports for the hydrogenation of CALD is reported. At the heart of the hydrogenation of CALD is the catalyst, since it provides the surface for the various reactions to take place. In this study, an in-depth study was conducted on the NCSs support, by varying pyrolysis time, pyrolysis temperatures and flow rates of gases to determine the physical and chemical properties. The effects of chemically modifying the surfaces of the NCS supports by functionalization with acid and doping with carbon were also investigated. NCSs which had undergone different pre-treatments procedures were then deposited with Pd nanoparticles using different metal deposition methods and the resultant catalysts tested for the hydrogenation of CALD.
109

Synthetic studies on hydroxylated cholesterols.

Georghiou, Paris Elias. January 1972 (has links)
No description available.
110

The Effect of Ethanol upon the Catalytic Hydrogenation of Lactose to Lactitol

Kasick, Andrew G. January 2019 (has links)
No description available.

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