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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

Studies related to reductive cyclization of alkynes

李柏昌, Li, Pak-cheong. January 1976 (has links)
published_or_final_version / Chemistry / Master / Master of Philosophy
162

Lewis acid-catalyzed asymmetric atom and group transfer radical cyclization reactions

Zheng, Baofu., 鄭保富. January 2005 (has links)
published_or_final_version / abstract / Chemistry / Doctoral / Doctor of Philosophy
163

Explorations on transition metal-catalyzed enantioselective cyclization reactions and applications of thiourea ligands

Yang, Min, 楊敏 January 2005 (has links)
published_or_final_version / abstract / Chemistry / Doctoral / Doctor of Philosophy
164

Signal space coding over rings

Castiñeira Moreira, Jorge January 2000 (has links)
No description available.
165

Nonradial oscillations of Saturn: Implications for ring system structure.

Marley, Mark Scott. January 1990 (has links)
Numerous wave and gap features observed in Voyager data of Saturn's rings are produced by resonances between the orbital frequencies of known external satellites and ring particle orbits. This thesis investigates the possibility that other, currently unassociated, ring features are generated by perturbations on ring participle orbits produced by non-axisymmetric gravitational fields resulting from acoustic oscillation modes of the planet. The frequencies of Saturnian low degree (l ≤ 8) fundamental (or f) mode oscillations are calculated for a variety of Saturn interior models which span the range of uncertainty of the interior structure of the planet. Corrections for rotation, oblateness, and possible differential rotation have been applied. Only the low degree f-modes are found to have frequencies and likely wave amplitudes in the range necessary to produce gap or wave features in the rings. The calculated positions of outer Lindblad resonances (OLR) for the degree l = 2,3,4, and 5 sectoral f-modes of a single Saturn model lie near four previously unassociated C-ring features. These features are the Maxwell gap and three waves identified as being forced at either OLR or inner vertical resonances. The outer vertical resonance (OVR) of the l = 5, m = 4 mode also overlaps the location of a wave which may be forced at either an OVR or an inner Lindblad resonance. Four other similar wave features, however, cannot be explained by oscillation mode resonances. This failure to account for all of the comparable unassociated C-ring waves is the principal inadequacy of the hypothesis. Other observed properties of the wave features, however, including their azimuthal wavenumbers m and the variation of amplitude with proposed oscillation mode degree are consistent with the proposed forcing. Planetary oscillation amplitudes of ∼1 m are required for gap opening; wave amplitudes of ∼10 cm are required for density wave production. The C-ring thus serves as a very sensitive f-mode detector. Observations by the Cassini spacecraft should unequivocally determine if the C-ring features are produced by planetary oscillation modes. If these observations confirm the association, significant new constraints could be placed on Saturnian energy transport, differential rotation, and core size.
166

Spray dynamics and air motion in the cylinder of G-DI engine

Feng, Guangjie January 2001 (has links)
No description available.
167

Catalysis and reactivity in chemistry and enzymology

Page, Michael I. January 1999 (has links)
No description available.
168

Iron (III) mediated ring expansion / cyclisation reactions

Thompson, David Francis January 1995 (has links)
No description available.
169

Ring closure reactions

Brennan, C. M. January 1988 (has links)
No description available.
170

Synthesis, structure determination and mechanism in thiophene derivatives

Weddell, Derek Alexander January 2001 (has links)
No description available.

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