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Antiproton-Proton Cross Sections at 1.0, 1.25, and 2.0 BeV

Description: The antiproton--proton interaction was studied at three energies, 2.0, 1.25, and 0.98 Bev. Antiprotons produced internally in the Revatron and channeled externally by a system of bending magnets and quadrupoles were selected from background particles by using a gas Cherenkov counter and scintillation counters. At the two lower energies, an electrostatic-magnetic velocity spectrometer was used to reject background particles. A liquidhydrogen target was completely surrounded by scintillation coun… more
Date: March 15, 1960
Creator: Coombes, C. A.
open access

Application of photothermal deflection spectroscopy to electrochemical interfaces

Description: This dissertation discusses the theory and practice of Photothermal Deflection Spectroscopy (PDS, which is also known as probe beam deflection spectroscopy, PBDS, probe deflection technique, and mirage effect spectroscopy) with respect to electrochemical systems. Much of the discussion is also relevant to non-electrochemical systems. PDS can measure the optical absorption spectrum of interfaces and concentration gradients in the electrolyte adjacent to the electrode. These measurements can be m… more
Date: March 1, 1992
Creator: Rudnicki, J. D.; McLarnon, F. R. & Cairns, E. J.
open access

Applications of electrochemically-modulated liquid chromatography (EMLC): Separations of aromatic amino acids and polycyclic aromatic hydrocarbons

Description: The research in this thesis explores the separation capabilities of a new technique termed electrochemically-modulated liquid chromatography (EMLC). The thesis begins with a general introduction section which provides a literature review of this technique as well as a brief background discussion of the two research projects in each of the next two chapters. The two papers which follow investigate the application of EMLC to the separation of a mixture of aromatic amino acids and of a mixture of … more
Date: March 27, 1998
Creator: Deng, L.
open access

Bio-Aerosol Detection Using Mass Spectrometry: Public Health Applications

Description: I recently spent a summer as an intern at the Lawrence Livermore National Laboratory. I worked on a project involving the real-time, reagentless, single cell detection of aerosolized pathogens using a novel mass spectrometry approach called Bio-Aerosol Mass Spectrometry (BAMS). Based upon preliminary results showing the differentiation capabilities of BAMS, I would like to explore the development and use of this novel detection system in the context of both environmental and clinical sample pat… more
Date: March 5, 2004
Creator: Ludvigson, L D
open access

Characterization of Functionalized Self-Assembled Monolayers and Surface-Attached Interlocking Molecules Using Near-Edge X-ray Absorption Fine Structure Spectroscopy

Description: Quantitative knowledge of the fundamental structure and substrate binding, as well as the direct measurement of conformational changes, are essential to the development of self-assembled monolayers (SAMs) and surface-attached interlocking molecules, catenanes and rotaxanes. These monolayers are vital to development of nano-mechanical, molecular electronic, and biological/chemical sensor applications. This dissertation investigates properties of functionalized SAMs in sulfur-gold based adsorbed … more
Date: March 24, 2004
Creator: Willey, T & Willey, T
open access

Chemisorption and catalytic reactivity of cobalt and sulfur monolayers on ordered molybdenum surfaces

Description: Complex Co/Mo sulfide catalysts are modelled by the chemisorption of layers on Mo single crystal surfaces. Growth and structure of overlayers on flat, stepped and kinked surfaces were investigated. Growth of Co overlayers on clean and S covered Mo surfaces was studied using AES and CO chemisorption; results reveal that Co grows as a flat monolayer on clean Mo surfaces. Co multilayers then form 3-D islands. When Co is deposited on S covered surfaces, the S overlayer migrates to the top; this top… more
Date: March 1, 1992
Creator: Knight, C. C.
open access

Cooling of highly charged ions in a Penning trap

Description: Highly charged ions are extracted from an electron beam ion trap and guided to Retrap, a cryogenic Penning trap, where they are merged with laser cooled Be{sup +} ions. The Be{sup +} ions act as a coolant for the hot highly charged ions and their temperature is dropped by about 8 orders of magnitude in a few seconds. Such cold highly charged ions form a strongly coupled nonneutral plasma exhibiting, under such conditions, the aggregation of clusters and crystals. Given the right mixture, these … more
Date: March 31, 2000
Creator: Gruber, L
open access

Design and test of a low jitter metal to metal contact solid dielectric switch

Description: A low jitter metal to metal contact solid dielectric switch was designed and tested. A metal to metal contact solid dielectric switch with a jitter of less than 25 ns is required for the 150 kJ experiment. Since this is one fourth the 100 ns jitter reported using exploding bridge foil (EBF) triggers, experiments to optimize this trigger were performed. A jitter of 25 ns was achieved using the EBF trigger and it was also achieved using a new type of trigger called the magnetic push trigger. This… more
Date: March 1, 1993
Creator: Domning, E. E.
open access

Determination of the feasibility of using open path FTIR to monitor levels of 3-methylfuran and 1-octen-3-ol for the purpose of detecting microbial contamination in indoor environments

Description: Studies have shown that the presence of microbial growth correlates with health complaints associated with sick building syndrome. Microbial growth may be found in damp places within a building, and may be dispersed to other areas if present in the HVAC system. Certain individuals may be especially sensitive to the presence of these microorganisms, and may experience adverse reactions at extremely low concentrations. Unfortunately, the source of the problem may not be discovered because many ti… more
Date: March 1, 1996
Creator: Olive, B.
open access

Determining Application Runtimes Using Queueing Network Modeling

Description: Determination of application times-to-solution for large-scale clustered computers continues to be a difficult problem in high-end computing, which will only become more challenging as multi-core consumer machines become more prevalent in the market. Both researchers and consumers of these multi-core systems desire reasonable estimates of how long their programs will take to run (time-to-solution, or TTS), and how many resources will be consumed in the execution. Currently there are few methods… more
Date: March 15, 2007
Creator: Elliott, M
open access

The Development of the Electrically Controlled High Power RF Switch and Its Application to Active RF Pulse Compression Systems

Description: In the past decades, there has been increasing interest in pulsed high power RF sources for building high-gradient high-energy particle accelerators. Passive RF pulse compression systems have been used in many applications to match the available RF sources to the loads requiring higher RF power but a shorter pulse. Theoretically, an active RF pulse compression system has the advantage of higher efficiency and compactness over the passive system. However, the key component for such a system an e… more
Date: March 20, 2009
Creator: Guo, Jiquan
open access

Development of vertexing and lifetime triggers and a study of B(s) mixing using hadronic decays at D0

Description: The D0 detector underwent a major upgrade to maximize its ability to fully exploit Run II at the Fermilab Tevatron, the world's highest energy collider. The upgrade included a completely new central tracking system with an outer scintillating fiber tracker and an inner silicon vertex detector all within a 2T superconducting solenoid. This thesis describes the development of high level trigger algorithms including vertexing, impact parameter significance and invariant mass, that utilize tracks f… more
Date: March 1, 2005
Creator: Barnes, Christopher P.
open access

An economic analysis of recordable injuries at Martin Marietta Energy Systems, Inc.

Description: The William-Steiger Occupational Safety and Health Act (OSHA) was passed by the Congress and signed by the President of the United States in 1970. This law required all companies with more than 25 employees to maintain information about each recordable injury, which is defined as any occupational illness or any work-related injury requiring more extensive treatment than first aid. However, compliance with OSHA standards did not require employers to keep records regarding the costs of recordable… more
Date: March 1, 1992
Creator: Johnson, E. K.
open access

Electron Transfer at Sensitized Semiconductor Electrodes

Description: Electron transfer from the excited state of sensitizing dyes to the conduction band of semiconductors has been studied through photoelectrochemical techniques. Two systems were analyzed in detail: rhodamine B on ZnO and rose bengal on TiO/sub 2/. Prior to electrochemical experimentation, the adsorption characteristics of these dyes were investigated using ZnO, ZnS, and TiO/sub 2/ single crystals as substrates. Absorbance measurements of the adsorbed dye were taken as a function of the solution … more
Date: March 1977
Creator: Spitler, Mark Thomas
open access

Energy development and CO{sub 2} emissions in China

Description: The objective of this research is to provide a better understanding of future Chinese energy development and CO{sub 2} emissions from burning fossil fuels. This study examines the current Chinese energy system, estimates CO{sub 2} emissions from burning fossil fuels and projects future energy use and resulting CO{sub 2} emissions up to the year of 2050. Based on the results of the study, development strategies are proposed and policy implications are explored. This study first develops a Base s… more
Date: March 1, 1993
Creator: Xiaolin Xi
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