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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.
51

Oxidative modifications of polymer surfaces

Boyd, Robert Deric January 1996 (has links)
Non-equilibrium plasma modification of polymer surfaces in an oxygen atmosphere provides a highly efficient, solventless method of raising the surface energy. The chemical and physical effects of non-equilibrium plasma treatment on polymer surfaces have been investigated. Oxygen glow discharge and silent discharge treatment of several polymers (polypropylene, polystyrene, polyphenylene oxide and polycarbonate) has been shown to cause both surface oxidation and chain scission at the polymer surface. This generates low molecular weight oxidised material on the polymer surface which conglomerates into globular features due to the difference in surface energy between the oxidised material and the untreated polymer. These features can be removed by solvent washing. Generally silent discharge treatment generates more low molecular weight oxidised material whereas oxygen glow discharge treatment generates more non-soluble oxidised material. Crystalline polymers react at a slower rate than amorphous material. During the treatment of a model crystalline polymer (hexatriacontane) the plasma attacks the edges of the crystal, rather than the surface, due to the greater chain mobility at the edge. Non-equilibrium plasma treatment of both miscible and immiscible polymer blends were investigated. The size and distribution of the globular features formed were found to be dependent on the blend composition. For the immicible polymer blend, non-equilibrium plasma treatment reveals the blend morphology mi sing from the difference in reaction rates of the parent polymers.
52

Atomic Force Microscopy Study of Model Lipid Monolayers

Rozina, Tamara January 2012 (has links)
Alzheimer's Disease (AD) is a neurodegenerative disorder that is prevalent among the elderly population. Aß protein has been heavily implicated in the pathogenesis of AD. This protein in its fibrillar form is a major component in the senile plaques that form on neuronal cellular membranes during the course of AD. Despite substantial efforts the exact mechanism of Aß toxicity towards a cell membrane is not well-understood. The determination of this mechanism, however, is of utmost importance, since the membrane presents the first site of Aß interaction with neurons, which in turn maybe the origin of Aß neurotoxicity. The purpose of this study was to find a lipid composition that can be used as a model of neuronal membrane for subsequent studies of the role of topographical heterogeneity (domain formation) on Aß-membrane interaction as related to AD. The lipids used in the study were 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC), 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoglycerol (POPG), cholesterol (Chol), sphingomyelin (SM) and ganglioside GM1 (GM1). These lipids were combined in different proportions and deposited on a mica substrate to form supported monolayers. They were then imaged with an atomic force microscope (AFM) to determine if any of them exhibited domain formation. Three of the studied samples: POPC/POPG/SM 40:40:20 +5%Chol, POPC/SM/Chol 75:20:5 and POPC/SM/GM1/Chol 74:2:1:23 were found to possess interesting topography, rich in structural features: pores and domains. The average height difference between the domain features for each sample was found to be 0.58±015 nm, 0.61±0.12 nm and 0.27±0:07 nm.
53

An investigation of Fluorocarbon, Silica and Cryptosporidium parvum surfaces by atomic force microscopy /

Considine, Robert F. Unknown Date (has links)
Thesis (PhDBiomedicalScience)--University of South Australia, 2001.
54

Colloidal forces measured between two solid surfaces and between a solid surface and an air bubble /

Fielden, Matthew L. Unknown Date (has links)
Thesis (PhD)--University of South Australia, 1997
55

The Design Of A Nanolithographic Process

Johannes, Matthew Steven, January 2007 (has links)
Thesis (Ph. D.)--Duke University, 2007. / Includes bibliographical references.
56

Development of nanopatterns on self assembled monolayer (sam) organic films using scanning probe microscope (spm) nanolithography techique/

Gül, Semra. Okur Salih January 2006 (has links) (PDF)
Thesis (Master)--İzmir Institute Of Technology, İzmir, 2006 / Keywords: Atomic force microscope, self assembled monolayer organic films, nanolithografy Includes bibliographical references (leaves. 109-112).
57

Quantification of the properties of nonlinear media using dual-probe atomic force microscopy

Aksu, Saltuk Bugra. January 1900 (has links)
Thesis (Ph.D.)--University of Nebraska-Lincoln, 2007. / Title from title screen (site viewed June 17, 2008). PDF text: xiii, 146 p. : ill. (some col.) ; 4 Mb. UMI publication number: AAT 3295233. Includes bibliographical references. Also available in microfilm and microfiche formats.
58

Atomic force microscopy for sorption studies

Vithayaveroj, Viriya. January 2004 (has links) (PDF)
Thesis (Ph. D.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2005. / Dr. Rina Tannenbaum, Committee Member ; Dr. Michael Sacks, Committee Member ; Dr. Sotira Yiacoumi, Committee Chair ; Dr. Costas Tsouris, Committee Co-Chair ; Dr. Ching-Hua Huang, Committee Member. Vita. Includes bibliographical references.
59

Drug/DNA interactions and condensation investigated with atomic force microscopy

Gadsby, Elizabeth Deibler. January 2004 (has links) (PDF)
Thesis (Ph. D.)--School of Chemistry and Biochemistry, Georgia Institute of Technology, 2005. Directed by Lawrence A. Bottomley. / William D. Hunt, Committee Member ; Nicholas V. Hud, Committee Member ; L. Andrew Lyon, Committee Member ; Lawrence A. Bottomley, Committee Chair ; Loren D. Williams, Committee Member. Vita. Includes bibliographical references.
60

Iterative learning control of hysteresis in piezo-based nano-positioners : theory and application in atomic force microscopes /

Leang, Kam K. January 2004 (has links)
Thesis (Ph. D.)--University of Washington, 2004. / Vita. Includes bibliographical references (leaves 141-161).

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