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Showing 1 to 17 of 17 for “"Ion Optics"”.
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Ion optics of an electrostatic lens
Thesis: B.S., Massachusetts Institute of Technology, Department of Physics, 1980
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Immersed Finite Element Particle-In-Cell Simulations of Ion Propulsion
… algorithm was developed for plasma simulations involving complex boundary conditions. The new algorithm is based on the three-dimensional immersed finite element method which is developed in this thesis, and a modified legacy particle-in-cell code. The model also applies a new meshing …
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Ionospheric Simulator (IonSim): Simulating Ionospheric conditions in a vacuum chamber
Understanding and improving ionospheric models is important for both military and civilian purposes. This understanding improves prediction of radio propagation used for communication and GPS navigation. Various space-borne instruments, such as retarding potential analyzers (RPAs) and ion traps are …
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Numerical optimization of ion transport in electrospray mass spectrometry
Electrospray ionization (ESI) has developed into a key component of investigative analyses of samples in numerous biological, chemical, and geological contexts due to its unique ability to preserve the structure of ionized species without fragmentation. It is thus important that we fully understand …
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Numerical optimization of ion transport in electrospray mass spectrometry
Electrospray ionization (ESI) has developed into a key component of investigative analyses of samples in numerous biological, chemical, and geological contexts due to its unique ability to preserve the structure of ionized species without fragmentation. It is thus important that we fully understand …
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Developing a spin polarized helium ion source for surface electronic structure studies
… spin polarized He$\sp+$ source for application in studies of electron spin correlations in ion neutralization at surfaces is described. The source is based on an optically pumped helium discharge. An rf discharge is used to produce metastable helium atoms in a clean pyrex glass cell. A 300 …
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Characterization of ionic liquid ion sources for focused ion beam applications
In the Focused Ion Beam (FIB) technique, a beam of ions is reduced to nanometer dimensions using dedicated optics and directed to a substrate for patterning. This technique is widely used in micro- and nanofabrication for etching, material deposition, microscopy, and chemical surface analysis. …
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Chip-scale quadrupole mass filters for a Micro-Gas Analyzer
… analysis. This tool has numerous applications ranging from national security, industrial processing, environmental monitoring, space exploration, and healthcare to name a few. These systems are typically large, heavy, power-hungry, and expensive, constraining its usage to a laboratory …
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Instrumentation and development of a mass spectrometry system for the study of gas-phase biomolecular ion reactions
<p>Gas-phase reactions of biomolecular ions are highly relevant to the understanding of structures and functions of the biomolecules. Mass spectrometry is a powerful tool in investigating gas-phase ion chemistry. Various mass spectrometers have been developed to explore ion/molecule reactions, …
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Design and implementation of a custom imaging mass spectrometer.
… chemical analysis. As such, MS has found application across practically every field of science today. One notable area where MS is used today is in the analysis of biological samples, such as tissues, where MS has been utilized for lipidomic, proteomic, metabolomic, etc. The work contained in this …
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DEVELOPMENT OF A LOW PRESSURE-INDUCTIVELY COUPLED PLASMA-ION SOURCE FOR MASS SPECTROMETRY
… low pressure-inductively coupled plasma (LP-ICP) ion source has been investigated for the production of atomic and molecular ions for mass spectrometry (MS). A dedicated LPICP- MS was constructed, by modifying a Hewlett Packard mass selective detector, to detect ions from the LP-ICP. The ion …
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Design and evaluation of a laser ion source for TITAN to measure 222Rn daughter product abundances
… focuses on developing and implementing a Laser Ion Source (LIS) at TRIUMF’s Ion Trap for Atomic and Nuclear Science (TITAN) facility to achieve high-precision isotope abundance ratio mea-surements across diverse materials. The project aims to quantify long-lived daughter products of 222Rn, …
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Fundamental studies of mixed gas plasmas in ICP-MS
… or removing these interference effects. In addition the use of mixed gas plasmas for sensitivity enhancement has been assessed using both wet and dry sample introduction systems. Simplex optimization procedures have been used throughout. The addition of nitrogen to all three argon gas flows of …
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Design, Fabrication, and Characterization of Carbon Nanotube Field Emission Devices for Advanced Applications
… as promising candidates for electron field emission (FE) cathodes in integrated FE devices. These nanostructured carbon materials possess exceptional properties and their synthesis can be thoroughly controlled. Their integration into advanced electronic devices, including not only FE cathodes, …
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Helium Atom Scattering from Chiral Structures
Helium Atom Scattering (HAS) is the only diffraction technique that combines absolute sur- face sensitivity with non-destructiveness and universality, but has been seldom applied to the study of chiral surfaces. The current thesis focuses on advancing the available theoretical and experimental tools …
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Design and Testing of a Prototype Slow Positron Beam at the NC State University PULSTAR Reactor
… the surface of materials utilizing the conservation of energy and momentum on the annihilation quanta. Radioactive sources are capable of producing slow positron rates on the order of 10⁶ Hz, but the pair production mechanism is necessary to produce more intense beams. The environment in the …
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Conception et réalisation d'un spectromètre de coïncidences photoion-photoélectron. Application à l'étude de molécules simples
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