• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 2828
  • 1046
  • 507
  • 266
  • 221
  • 131
  • 71
  • 71
  • 33
  • 15
  • 15
  • 13
  • 12
  • 11
  • 11
  • Tagged with
  • 6651
  • 2416
  • 1763
  • 1007
  • 998
  • 908
  • 700
  • 697
  • 695
  • 645
  • 612
  • 583
  • 565
  • 532
  • 512
  • 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.
191

A Vertical Coarse Approach Scanning Tunneling Microscope

Drevniok, BENEDICT 25 June 2009 (has links)
A Pan-style scanning tunneling microscope (STM), with a vertical coarse approach mechanism, was designed, built and tested. The microscope will be operated in ultra-high vacuum and also at cryogenic temperatures (8 K) inside a continuous flow cryostat. Fundamental differences in operating principle exist between the new microscope and the beetle-type inertial sliders [1] that have been the mainstay of the group for the last eight years. While Pan-style microscopes do already exist [2], they remain challenging to build, and an active area of research [3]. This system represents a bold departure from well-trodden paths, and will greatly expand the range of experiments that our group can perform. The operating principles of inertial piezoelectric motors are detailed. Design guidelines for a piezoelectric motor are given, and used in the design of the vertical coarse approach motor. A simple, inexpensive implementation for creating waveforms with an extremely fast fall time is discussed. Motor performance is tested, and a minimum step size of 20nm is found for frequencies ranging from 0 Hz to 3 kHz. The motor operates with high dynamic range: individual 20nm steps can be taken, as well as being able to move at a velocity of 0.4mm s−1. Little is known about the vibrational properties of Pan-style microscopes. Vibrational testing of the microscope revealed the expected scanner bending mode at 1.6 kHz (above the scanner bending mode of our beetles at 1.2 kHz), and a complicated response signal above this frequency. Custom extension springs for an eddy-current damping system are built and tested. A low resonant frequency of 1.8 Hz is found, which is ideal for the application. Initial testing of the STM in ambient conditions is performed on two different surfaces. A moir´e supermesh [4] with periodicity 3nm is observed on a highly-oriented pyrolytic graphite (HOPG) surface, and agrees well with previously published results. Using a flame-annealed Gold on mica surface, a low drift rate of 0.6nm s−1 is observed over a period of 13 minutes. Single-height atomic steps are observed on both surfaces. Additionally, the microscope is shown to be capable of zooming into different features on a surface, and scanning at different length scales. / Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2009-06-24 13:06:16.683
192

The fabrication of specialized probes for surface metrology

Williams, Ryan Donald, January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.
193

Adaptation and application of morphological pseudoconvolutions to scanning tunneling and atomic force microscopy /

Weisman, Andrew D. January 1991 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 1991. / Spine title: Application of morphological pseudoconvolutions to STM images. Includes bibliographical references.
194

Near Field Scanning Optical Microscopy(NSOM) of nano devices

Low, Chun Hong. January 2008 (has links) (PDF)
Thesis (M.S. in Combat Systems Science and Technology)--Naval Postgraduate School, December 2008. / Thesis Advisor(s): Haegel, Nancy M. ; Luscombe, James. "December 2008." Description based on title screen as viewed on January 29, 2009. Sponsoring/Monitoring Agency Report Number: "DMR-0526330." Includes bibliographical references (p. 59-61). Also available in print.
195

Nucleation and growth of inorganic crystals at the organic-inorganic interface /

Dennis, Shelli R. January 1998 (has links)
Thesis (Ph. D.)--University of Washington, 1998. / Vita. Includes bibliographical references (leaves [140]-152).
196

Laser scanning microscopy of broad freezing interfaces with applications to biological cells /

Neils, Christopher Martin, January 2000 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 203-215). Available also in a digital version from Dissertation Abstracts.
197

Photophysical characterization and near-field scanning optical microscopy of dilute solutions and ordered films of alkyl-substituted polyfluorenes /

Teetsov, Julie Ann, January 2000 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 177-184). Available also in a digital version from Dissertation Abstracts.
198

Development of chemomechanical functionalization and nanografting on silicon surfaces /

Lee, Michael V. January 2007 (has links) (PDF)
Thesis (Ph. D.)--Brigham Young University. Dept. of Chemistry and Biochemistry, 2007. / Includes bibliographical references.
199

Multiphoton microscopy, fluorescence lifetime imaging and optical spectroscopy for the diagnosis of neoplasia

Skala, Melissa Caroline, January 2007 (has links) (PDF)
Thesis (Ph. D.)--Duke University, 2007. / Includes bibliographical references.
200

Fabrication of atomic force microscope probes integrated with microelectrodes for micro four-point probe and SECM-AFM

Shin, Heungjoo. January 2006 (has links)
Thesis (Ph. D.)--Mechanical Engineering, Georgia Institute of Technology, 2006. / Levent Degertekin, Committee Member ; William P. King, Committee Member ; Boris Mizaikoff, Committee Member ; Mark G. Allen, Committee Member ; Peter J. Hesketh, Committee Chair.

Page generated in 0.0458 seconds