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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.
1

Electron microscopy calibration and application of the electron microscope to the solution of problems associated with the manufacture of iron oxide pigments /

Wright, Ralph R. Dechant, William G. January 1950 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute. 1950. / Abstract. Includes bibliographical references (leaves 128-149). Also available via the Internet.
2

Orbital spin-splitting factors for conduction electrons in lead

Ren, Yan-Ru January 1985 (has links)
A detailed experimental study has been made of the spin-splitting factors ℊc for magnetic Landau levels associated with conduction electrons in extremal orbits on the Fermi surface of lead. This information has been derived from the waveform of the de Haas-van Alphen (dHvA) quantum oscillations in the magnetization of single-crystal lead spheres at temperatures of about 1.2 K and with applied magnetic fields in the range 50-75 kG. A commercial spectrum analyzer has been used to provide on-line values of the harmonic amplitudes in the dHvA waveform, and the values of ℊc have been extracted from the relative strengths of the harmonics. Serious systematic errors in ℊc can arise on account of waveform distortions caused by the small and subtle difference between the externally applied field H and the magnetizing field B acting on the conduction electrons. In 1981 Gold and Van Schyndel demonstrated that these 'magnetic-interaction' distortions could be suppressed to a large extent by using negative magnetic feedback to make the induction B within the sample be the same as H (or very nearly so). This thesis describes the first in-depth application of the magnetic-feedback technique to the systematic study of any metal. Particular attention has been paid to the effect of sample inhomogeneity, and Shoenberg's treatment of the magnetic interaction in a non-uniform sample has been generalized to include magnetic feedback. This theory accounts well for many features in the experimental data, especially those which remained a puzzle in the earlier work of Gold and Van Schyndel. Experimental ℊc values are given for the first time for most of the extremal orbits on the lead Fermi surface and for high-symmetry directions of the magnetic field. Indeed these are the most detailed data reported for any polyvalent metal. The ℊc factors for the different orbits and field directions are found to span the range from 0.56 to 1.147. These large net deviations from the free-electron value ℊ₀ = 2.0023 are consequences of the strong spin-orbit and electron-phonon interactions, and an attempt has been made to separate these two contributions to the ℊ-shifts. / Science, Faculty of / Physics and Astronomy, Department of / Graduate
3

Pair correlated atoms in ultracold fermi gas. / 超低溫費米氣體中的對關聯粒子 / Pair correlated atoms in ultracold fermi gas. / Chao di wen fei mi qi ti zhong de dui guan lian li zi

January 2007 (has links)
Pong, Yue Hin = 超低溫費米氣體中的對關聯粒子 / 龐宇軒. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 77-81). / Text in English, abstracts in English and Chinese. / Pong, Yue Hin = Chao di wen fei mi qi ti zhong de dui guan lian li zi / Pang Yuxuan. / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- Review on BCS theory --- p.4 / Chapter 2.1 --- BCS in uniform gas --- p.4 / Chapter 2.2 --- Hartree Fock Bogoliubov equations --- p.7 / Chapter 2.3 --- Regularization techniques --- p.13 / Chapter 2.4 --- Homogeneous solution to HFB --- p.15 / Chapter 3 --- HFB Computation --- p.17 / Chapter 3.1 --- Example: 1D infinite well --- p.18 / Chapter 3.2 --- Example: 1D SHO --- p.22 / Chapter 3.3 --- Example: Spherical harmonic oscillator --- p.23 / Chapter 3.4 --- Conclusion --- p.26 / Chapter 4 --- Natural Orbits --- p.28 / Chapter 4.1 --- Two-point correlation functions --- p.29 / Chapter 4.2 --- Connection with the BCS --- p.32 / Chapter 4.3 --- Natural orbits in a spherical harmonic potential --- p.33 / Chapter 4.4 --- Remarks --- p.38 / Chapter 5 --- Bosonic characters of atomic Cooper pairs across resonance --- p.43 / Chapter 5.1 --- Resonance in Fermi gas --- p.44 / Chapter 5.2 --- Bosonic tests --- p.50 / Chapter 5.3 --- Choosing a Cooper pair wave function --- p.52 / Chapter 5.3.1 --- Cooper pair I --- p.52 / Chapter 5.3.2 --- Cooper pair II --- p.55 / Chapter 5.4 --- Results in a uniform gas --- p.55 / Chapter 5.5 --- Remark --- p.61 / Chapter 6 --- Time dependent BCS: A numerical study --- p.63 / Chapter 6.1 --- Time evolution in uniform BCS --- p.64 / Chapter 6.2 --- Perturbation to interaction strength --- p.66 / Chapter 6.2.1 --- Sudden decrease in the interaction strength --- p.66 / Chapter 6.2.2 --- Sinusoidal variation of interaction strength --- p.68 / Chapter 6.2.3 --- A decaying energy gap --- p.69 / Chapter 6.3 --- Perturbation to particle numbers --- p.71 / Chapter 6.4 --- Remarks --- p.74 / Chapter 7 --- Summary and Outlook --- p.75 / Chapter 7.1 --- Outlook --- p.75 / Bibliography --- p.77 / Chapter A --- Analytic solutions to homogeneous BCS --- p.82 / Chapter B --- Local Density Approximation (LDA) --- p.84 / Chapter B.1 --- One dimensional LDA --- p.85 / Chapter C --- Finding the regularized Green's Function --- p.87 / Chapter D --- Variational approach to finding natural orbits --- p.90 / Chapter D.1 --- Variation with respect to natural orbits --- p.90 / Chapter D.2 --- Variation with respect to the occupation amplitude --- p.93
4

Characterizing cavity containing materials using electron microscopy : A study of metal oxides, mesoporous crystals and porous material containing nanosized metal-particles

Klingstedt, Miia January 2011 (has links)
This thesis concerns the characterization of novel materials by utilizing electron microscopy techniques. The examined materials contain cavities with certain attributes that enables desired properties for applications such as gas separation, catalysis and fuel cells. The specimens concerned herein belong to the following groups of materials: Metal oxides in the Sb-W-Mo-O system; ordered mesoporous silicas and carbons; hollow spheres containing Au-nanoparticles; zeolite LTA incorporated with mesopores; metal organic frameworks doped with nickel. With scanning electron microscopy (SEM) and transmission electron microscopy (TEM) you get vast possibilities within the field of characterization. This thesis utilizes conventional electron microscopy techniques such as imaging, energy-dispersive spectroscopy and electron diffraction as well as reconstruction techniques, such as exit-wave reconstruction, electron tomography and electron crystallography. Furthermore, the sample preparation technique cross-section polishing has been used in conjunction with low voltage SEM studies. The scientific approach is to gain knowledge of nano-sized cavities in materials, in particular their shape, size and content. The cavities often have irregularities that originates from the synthesis procedure. In order to refine the synthesis and to understand the properties of the material it is required to carefully examine the local variations. Therefore average characterization techniques such as crystallography needs to be combined with local examination techniques such as tomography. However, some of the materials are troublesome to investigate since they to some extent bring limitations to or gets easily damaged by the applied characterization technique. For the development of novel materials it is essential to find means of overcoming also these obstacles. / At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 6: Submitted.
5

Electronic spectroscopy of various molecular systems by low-energy, variable-angle, electron impact

Frueholz, Robert Paul. Kuppermann, Aron. January 1978 (has links)
Thesis (Ph. D.)--California Institute of Technology, 1978. UM #78-15,971. / Advisor names found in the Acknowledgments pages of the thesis. Title from home page. Viewed 01/19/2010. Includes bibliographical references.
6

Characterization of two-dimensional electrostatic potential profiles in deep submicron MOSFET devices

Ko, Kil-soo. January 2003 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2003. / Vita. Includes bibliographical references. Available also from UMI Company.
7

Characterization of two-dimensional electrostatic potential profiles in deep submicron MOSFET devices

Ko, Kil-soo 28 August 2008 (has links)
Not available / text
8

Vectorial field structure in the focal region of microwave mirrors.

Legendre, Jacques Pierre January 1970 (has links)
No description available.
9

The unitary Fermi gas /

Drut, Joaquín E. January 2008 (has links)
Thesis (Ph. D.)--University of Washington, 2008. / Vita. Includes bibliographical references (p. 82-91).
10

Measurement of electron mobility in argon master project /

Mishouil, Massoud. January 1970 (has links)
Thesis (M.S.)--University of Michigan, 1970.

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