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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.
31

Diffraction of atoms by a standing-wave light field.

Schumacher, Erik. January 1992 (has links)
We study theoretically the diffraction of atoms by a standing-wave light field. Conceptually the text is divided into two parts. In the first part we deal with the coherent interaction only. We use a band theoretical approach to describe the laser-atom interaction, and to characterize two-beam resonances (Dopplerons and Bragg resonances). These two-beam resonances are major candidates to develop effective atom beam splitters. We study the interaction with classical light fields as well as with quantum fields. In the second part we take incoherent processes, i.e. spontaneous emission, into account and present a numerical scheme for the solution of the generalized optical Bloch equations. This scheme is based on the split-operator technique, and we use it to study numerically the influence of spontaneous emission on the diffraction process. We compare our results with recent experimental data, and investigate the impact of spontaneous emission on the performance of two-beam resonances.
32

Non-linear wave diffraction by a vertical, circular cylinder in water of finite depth

Williams, A. N. January 1982 (has links)
No description available.
33

Structural studies of some disordered molybdates and manganates and manganates

Cooper, Steven P. January 1999 (has links)
No description available.
34

Synthesis and characterisation of unusual sodalites

Mead, Philip John January 1996 (has links)
No description available.
35

Imaging theory of surface-breaking discontinuities

Tew, R. January 1987 (has links)
No description available.
36

The structure and properties of absorbed layers by X-ray and neutron scattering

Clarke, Stuart M. January 1989 (has links)
No description available.
37

Synthesis of alkaline earth transition metal sulfides

Rees, David Alan January 2000 (has links)
No description available.
38

Crystal chemistry of some novel rock salt- and perovskite-related oxides

Mather, Glenn C. January 1995 (has links)
The family of phases Li3M2XO6 (M = Mg, Co, Ni; X = Nb, Ta, Sb) has a novel rock salt superstructure in which the X cations occupy one set of octahedral sites with the Li and M cations distributed over three octahedral sites in a non-random manner. The non-random site occupancies vary depending on M and X and appear to be an equilibrium feature of the structure. Li3Ni2NbO6 undergoes a continuous order-disorder transition and can be doped with Cr3+ by a number of mechanisms to give either ordered or disordered rock salt structures. The phase diagram of the solid solutions of general formula Li3-xNi2-xCr xNbO6 has been determined and shows solid solutions for both ordered and disordered polymorphs with a transition zone that is 200-300A°C wide. Li3Ni2TaO6 and Cr-doped Li3Ni 2NbO6 compositions are modest semiconductors. The alpha and beta structures of polymorphic Li2CuZrO 4 have been determined. Both structures are ordered rock salt with unique sites for Zr and one set of Li atoms; in the alpha polymorph, Cu and the other set of Li atoms are partially ordered over two sites, but in beta-Li 2CuZrO4 all cations are uniquely ordered. In the phase transition from alpha-Li2CuZrO4 to the low temperature beta polymorph, the CuO6 octahedra, which predominantly corner-share in alpha, become edge-sharing. Magnetic susceptibility data indicate that, in both polymorphs, there are both ferromagnetic and antiferromagnetic interactions. The predominant interactions in the alpha phase are antiferromagnetic whereas in the beta polymorph, they are ferromagnetic. Conductivity measurements show that beta-Li2CuZrO4 is a modest semiconductor.
39

The construction of an electron diffraction unit

Joynson, Reuben Edwin. January 1950 (has links)
Call number: LD2668 .T4 1950 J69 / Master of Science
40

Experimental and theoretical studies on the intensity subpeaks of laser diffraction lines of single frog skeletal muscle fibres.

January 1982 (has links)
by Chan Che Ping. / Chinese title: / Bibliography : leaf 132 / Thesis (M.Phil.)--Chinese University of Hong Kong, 1982

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