Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 6 of 6

Full-Text Articles in Physical Sciences and Mathematics

Halo Ion Trap Mass Spectrometry: Design, Instrumentation, And Performance, Miao Wang Nov 2010

Halo Ion Trap Mass Spectrometry: Design, Instrumentation, And Performance, Miao Wang

Theses and Dissertations

New ion trap mass spectrometry (ITMS) instrumentation, the toroidal IT and halo IT, were developed to meet the significant growth in on-site analysis applications. The miniature toroidal IT mass analyzer was operated with radio frequency (RF) trapping voltages of 3 kVp-p or less. Despite its reduced dimensions, it has roughly the same ion trapping capacity as conventional 3D quadrupole ITs. Unit-mass resolved spectra for n-butylbenzene, xenon, and naphthalene were obtained. The desired linear mass scale was obtained using conventional mass-selective instability scan combined with resonance ejection. The halo IT was also based on toroidal trapping geometry and microfabrication technology, consisting …


Characterization Of Glycation Sites On Human Serum Albumin Using Mass Spectrometry, Omar S. Barnaby Apr 2010

Characterization Of Glycation Sites On Human Serum Albumin Using Mass Spectrometry, Omar S. Barnaby

Department of Chemistry: Dissertations, Theses, and Student Research

The modification of proteins by reducing sugars is a process that occurs naturally in the body. This process, which is known as glycation, has been linked to many of the chronic complications encountered during diabetes. Glycation has also been linked to changes in the binding of human serum albumin (HSA) to several drugs and small solutes in the body. While these effects are known, there is little information that explains why these changes in binding occur. The goal of this project was to obtain qualitative and quantitative information about glycation that occurs on HSA. The first section of this dissertation …


Statistical Analysis Of Visible Absorption Spectra And Mass Spectra Obtained From Dyed Textile Fibers, Katie Margaret White Jan 2010

Statistical Analysis Of Visible Absorption Spectra And Mass Spectra Obtained From Dyed Textile Fibers, Katie Margaret White

Electronic Theses and Dissertations

The National Academy of Sciences recently published a report which calls for improvements to the field of forensic science. Their report criticized many forensic disciplines for failure to establish rigorously-tested methods of comparison, and encouraged more research in these areas to establish limitations and assess error rates. This study applies chemometric and statistical methods to current and developing analytical techniques in fiber analysis. In addition to analysis of commercially available dyed textile fibers, two pairs of dyes are selected based for custom fabric dyeing on the similarities of their absorbance spectra and dye molecular structures. Visible absorption spectra for all …


Corrosion Behavior Of Copper Thin Films In Organic Hf-Containing Cleaning Solution For Semiconductor Applications, Nabil George Mistkawi, Makarem A. Hussein, Malgorzata Ziomek-Moroz, Shankar B. Rananavare Jan 2010

Corrosion Behavior Of Copper Thin Films In Organic Hf-Containing Cleaning Solution For Semiconductor Applications, Nabil George Mistkawi, Makarem A. Hussein, Malgorzata Ziomek-Moroz, Shankar B. Rananavare

Chemistry Faculty Publications and Presentations

The corrosion behavior of electrochemically deposited copper thin films in deaerated and non-deaerated commercial cleaning solutions containing HF was investigated. Potentiodynamic polarization experiments were carried out to determine active, active–passive, passive, and transpassive regions. Corrosion rates were calculated from Tafel slopes. The addition of hydrogen peroxide to the solution and its influence on corrosion was also investigated by employing inductively coupled plasma-mass spectroscopy (ICP-MS) and X-ray photoelectron spectroscopy (XPS). The ICP-MS and potentiodynamic methods yielded comparable Cu dissolution rates. Surface analysis using atomic force microscopy and scanning electron microscopy, performed before and after the cleaning solution treatment, did not reveal …


Copper Thin-Film Dissolution/Precipitation Kinetics In Organic Hf Containing Cleaning Solution, Nabil George Mistkawi, Makarem A. Hussein, Malgorzata Ziomek-Moroz, Shankar B. Rananavare Jan 2010

Copper Thin-Film Dissolution/Precipitation Kinetics In Organic Hf Containing Cleaning Solution, Nabil George Mistkawi, Makarem A. Hussein, Malgorzata Ziomek-Moroz, Shankar B. Rananavare

Chemistry Faculty Publications and Presentations

The corrosion behavior of electrochemically deposited copper thin films in deaerated and non-deaerated commercial cleaning solution containing HF has been investigated. Thin-film copper dissolution and reaction kinetics were investigated by monitoring Cu2+ , employing inductively coupled plasma–mass spectroscopy, and the oxidation states of copper on Si wafer surface, employing X-ray photoelectron spectroscopy. It was determined that the reaction kinetics is first order with respect to both HF and oxygen concentrations. A kinetic scheme involving reduction of oxygen and oxidation of Cu0 and Cu1+ is proposed, which is consistent with the experimentally determined reaction kinetic orders and the …


Microfluidic Devices Interfaced To Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry For Proteomics, Jeonghoon Lee Jan 2010

Microfluidic Devices Interfaced To Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry For Proteomics, Jeonghoon Lee

LSU Doctoral Dissertations

Microfluidic interfaces were developed for off-line matrix-assisted laser desorption/ionization mass spectrometry (MALDI). Microfluidic interfaces allow samples to be manipulated on-chip and deposited onto a MALDI target plate for analysis. For this research, microfluidic culturing devices and automated digestion and deposition microfluidic chip platforms were developed for the identification of proteins. The microfluidic chip components were fabricated on a poly(methyl methacrylate), PMMA, wafer using the hot embossing method and a molding tool with structures prepared via micromilling. One of the most important components of the chip system was a trypsin microreactor. An open channel microreactor was constructed in a 100 µm …