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Full-Text Articles in Physics

High Speed Atomic Force Microscope Design Using Dvd Optics, Thomas Carlson May 2014

High Speed Atomic Force Microscope Design Using Dvd Optics, Thomas Carlson

Theses and Dissertations

We examine the design of a high speed atomic force microscope using an optical pickup from a commercially available compact disc/digital versatile disc drive. An investigation of the commercial optical pickup is done with the goal of determining how it can be used for dimensional measurements on nanometer scale. An evaluation of noise sources, imaging capabilities, and functionality is performed.


Investigating Mechanical Properties Of Metallic Nanowires Using Molecular Dynamics, Alex Khammang Apr 2014

Investigating Mechanical Properties Of Metallic Nanowires Using Molecular Dynamics, Alex Khammang

Theses and Dissertations

Metallic nanowires have useful applications in scanning tunneling microscopes and atomic force microscopes due to their unique sensitivity to force and electricity. These unique properties arise because of the large surface area to volume ratio. One of these properties is that introducing twinning planes the mechanical properties of metallic nanowires can be altered. The effects of twinning planes on metallic nanowires were studied using molecular dynamics simulations. Silver, copper, and nickel nanowires with and without twinning planes were simulated with engineering strain until the first yielding stress was obtained. The radial simulations showed that as the radius of twinned nanowires …


Aromaticity Rules In The Development Of Negative Ions, Brandon Child Apr 2014

Aromaticity Rules In The Development Of Negative Ions, Brandon Child

Theses and Dissertations

Organic molecules are known for their stability due to aromaticity. Superhalogens, on the other hand, are highly reactive anions, whose electron affinity is larger than that of chlorine. This thesis, using first principles calculations, explores possible methods for creation of superhalogen aromatic molecules while attempting to also develop a fundamental understanding of the physical properties behind their creation. The first method studied uses anionic cyclopentadienyl and enhances its electron affinity through ligand substitution or ring annulation in combination with core substitutions. The second method studies the possibilities of using benzene, which has a negative electron affinity (EA), as a core …


Characterization Of Individual Charged Au25(Sg)18 Clusters And Their Enhancement Of Single Molecule Mass Spectrometry, Christopher Angevine Jan 2014

Characterization Of Individual Charged Au25(Sg)18 Clusters And Their Enhancement Of Single Molecule Mass Spectrometry, Christopher Angevine

Theses and Dissertations

Metallic quantum clusters are stable structures that can exhibit many useful magnetic, chemical, and optical properties. Developing clusters for specific applications requires accurate methods for characterizing their physical and chemical properties. Most cluster characterization methods are ensemble-based measurements that can only measure the average values of the cluster properties. Single cluster measurements improve upon this by yielding information about the distribution of cluster parameters. This investigation describes the initial results on a new approach to detecting and characterizing individual gold nanoclusters (Au25(SG)18) in an aqueous solution with nanopore-based resistive pulse sensing. We also present a new application where the clusters …


An Investigation Of Nurbs-Based Deformable Image Registration, Travis J. Jacobson Jan 2014

An Investigation Of Nurbs-Based Deformable Image Registration, Travis J. Jacobson

Theses and Dissertations

Deformable image registration (DIR) is an essential tool in medical image processing. It provides a means to combine image datasets, allowing for intra-subject, inter-subject, multi-modality, and multi-instance analysis, as well as motion detection and compensation. One of the most popular DIR algorithms models the displacement vector field (DVF) as B-splines, a sum of piecewise polynomials with coefficients that enable local shape control. B-splines have many advantageous properties in the context of DIR, but they often struggle to adequately model steep local gradients and discontinuities. This dissertation addresses that limitation by proposing the replacement of conventional B-splines with a generalized formulation …