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 counters so that all charged secondaries from the antiproton--proion interactions could be detected. With the information obtained from these counters, the --p-bar--p total, elastic, inelastic, and charge-exchange cross sections and the angular distribution of the elastic scatterings were obtained at each energy. The total cross section was found to be 80, 89, and 100 mb at 2.0 1.25. and 0.98 Bev. respeclively. The inelastic cross section was about twothirds of ihe total cross section at each energy. It was found that each of the partial cross sections was dropping off slowly with energy. The results were fitted by an optic al-model c alculation. (auth)

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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 made on a wide variety of electrode surfaces and can be performed under dynamic conditions. The first three chapters discuss the theory of the phenomena that can be detected by PDS, and the equipment used in a PDS system. A ``secondary gradient technique`` is proposed, which places the probe beam on the back of an electrode. The results of a numerical model yield a method for determining the offset of the probe beam from the electrode surface based on the frequency response of the PDS signal. The origin and control of noise in the PDS signal are discussed. A majority of the signal noise appears to be acoustic in origin. The electrochemical oxidation of platinum is used to demonstrate that PDS has sub-monolayer sensitivity necessary to study interfacial chemistry. The results allow us …

The major purpose of this descriptive study was to identify the reasoning strategies used by seventh- and eighth grade severely disabled remedial reading students when attempting to comprehend expository and narrative prose. Additional research questions dealt with the most frequently used strategies; correct responses to questions through the use of strategies; strategies used when responding to narrative and expository prose; strategies used when answering literal and inferential questions; and the strategies used by individual students.

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 polycyclic aromatic hydrocarbons (PAHs). The last section presents general conclusions and summarizes the thesis. References are compiled in the reference section of each chapter. The two papers have been removed for separate processing.

A thesis, Assessing Student Achievement in Art, A Study of The Feasibility of Achievement Testing in Art. Submitted to: The Getty Center for Education in the Arts, The J. Paul Getty Trust by Ralph Hoepfner, Ph.D. The report on feasibility of developing curriculum-fair achievement tests the art on both positive and negative notes. During the 1983-84 school year an achievement test was developed to assess the school children's knowledge.

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 pathogen detection. I would also like to explore the broader public health applications that a system such as BAMS might have in terms of infectious disease prevention and control. In order to appreciate the potential of this instrument, I will demonstrate the need for better pathogen detection methods, and outline the instrumentation, data analysis and preliminary results that lead me toward a desire to explore this technology further. I will also discuss potential experiments for the future along with possible problems that may be encountered along the way.

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This study investigates the causes of the Iranian revolution of 1978-79. To this end, the different theories of revolution are reviewed in Chapter One. Chapter Two provides a discussion of the historical background of the country and the role the clergy played in shaping its political development. Socioeconomic and political factors which contributed to the outbreak of this revolution are examined in the following two chapters. Finally, an attempt is made to draw some conclusions on whether existing theories of revolution can fully explain the Iranian upheaval of 1978-79 or not. For the preparation of this study United States government documents and Iranian and English language scholarly works were consulted.

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 molecular monolayers using quantitative spectroscopic techniques including near-edge x-ray absorption fine structure spectroscopy (NEXAFS) and x-ray photoelectron spectroscopy (XPS). The stability of the gold-thiolate interface is addressed. A simple model SAM consisting of dodecanethiol adsorbed on Au(111) degrades significantly in less than 24 hours under ambient laboratory air. S 2p and O 1s XPS show the gold-bound thiolates oxidize to sulfinates and sulfonates. A reduction of organic material on the surface and a decrease in order are observed as the layer degrades. The effect of the carboxyl vs. carboxylate functionalization on SAM structure is investigated. Carboxyl-terminated layers consisting of long alkyl-chain thiols vs. thioctic acid with short, sterically separated, alkyl groups are compared and contrasted. NEXAFS shows a conformational change, or chemical switchability, with carboxyl groups tilted over and carboxylate endgroups more upright. Surface-attached loops and simple surface-attached rotaxanes are quantitatively …

The differential cross section for charge-exchange scattering of negative pions by hydrogen has been observed at 230, 260, 290, 317, and 371 Mev. The reaction was observed by detecting one gamma ray from the {pi}{sup 0} decay with a scintillation-counter telescope.

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 topmost overlayer reduces CO adsorption capacity. While growth mode of Co overlayers are similar on flat and stepped surfaces, the number and type of ordered Co and S structures on flat and stepped surfaces are different. In the case of Co, an ordered (3 {times} 1) structure is formed on Mo(910) and (28,4,1) surfaces; this structure does not develop on clean (100) surface. Only one of two possible (3 {times} 1) Co domains are formed on Mo(910) and Mo(28,4,1) surfaces. These domains have one side of (3 {times} 1) unit cell parallel to the step edges, suggesting that Co adsorbs at the step edges. The (3 {times} 1) structure does not form on Mo(911) surface, indicating that step …

The problem of this study was to assess the concerns and locus of control of black women enrolled in an urban community college district and to answer the following question. What is the relationship between each of those concerns and locus of control and each of the following demographic data: current hourly enrollment, number of college credits earned, age, marital status, number of dependent children, age of youngest child, estimated total annual income, and time of day of classes (whether the majority of their classes are during the day, at night, on Saturdays, any combination of the three or mostly telecourses)?

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 plasmas can be studied as analogues of high density plasmas like white dwarf interiors, and potentially can lead to the development of cold highly charged ion beams for applications in nanotechnology. Due to the virtually non existent Doppler broadening, spectroscopy on highly charged ions can be performed to an unprecedented precision. The density and the temperature of the Be{sup +} plasma were measured and highly charged ions were sympathetically cooled to similar temperatures. Molecular dynamics simulations confirmed the shape, temperature and density of the highly charged ions. Ordered structures were observed in the simulations.

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An interactive text editor is a computer program that allows a user to create and revise a target document such as program statements, manuscript text, and numeric data through an online terminal and the computer. It allows text to be modified and corrected many orders of magnitude faster and more easily than would manual correction. The most important characteristic of the text editor is its convenience for the user. Such convenience requires a simple, mnemonic command language which is easy to use and understand.

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 trigger uses the magnetic force between the two plates of a parallel plate transmission line to push the dielectric. It was found to be better than the EBF trigger because it was easier to design, easier to implement and did less damage to switch components.

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 times the microbial growth is not visible. However, there are some volatile organic compounds that are given off by certain microorganisms which may be used to determine the presence of microbial contamination. 3-Methylfuran is an excellent indicator of growing fungi. It is produced by a majority of fungi, and can be used as an indicator of ongoing growth. 1-Octen-3-ol is also produced by a number of fungi, and has been used in the past as an indicator of such. These two compounds and many other volatiles given off by microorganisms have been termed microbial volatile organic compounds (MVOCs). Many of these compounds are commonly found in indoor air, and thus, may be present even when there is not microbial contamination.

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 of determining these values, and those that do exist are either overly simplistic in their assumptions or require great amounts of effort to parameterize and understand. One previously untried method is queuing network modeling (QNM), which is easy to parameterize and solve, and produces results that typically fall within 10 to 30% of the actual TTS for our test cases. Using characteristics of the computer network (bandwidth, latency) and communication patterns (number of messages, message length, time spent in communication), the QNM model of the NAS-PB CG application was applied to MCR and ALC, supercomputers at LLNL, and the Keck Cluster at USF, with average errors of 2.41%, 3.61%, and -10.73%, respectively, compared to the actual TTS observed. While additional work is necessary to improve the predictive capabilities of …

No matter how extended the use of the computer is, the printed document is still the primary medium for the presentation information, and will continue to be for some time. The use of computing facilities for preparation and production of the document is becoming as prevalent as their use for numeric computation. Commercially, document preparation systems are now a standard facility at research institution, and they have become quite common on each computer program. A conventional document preparation system usually contains two parts: a text editor used to create, enter, update, and maintain the text and control words that comprise the document in its "input" form, and a text formatter used to process that input and produce the final document.

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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 element capable of switching hundreds of megawatts of RF power in a short time compared to the compressed pulse width is still an open problem. In this dissertation, we present a switch module composed of an active window based on the bulk effects in semiconductor, a circular waveguide three-port network and a movable short plane, with the capability to adjust the S-parameters before and after switching. The RF properties of the switch module were analyzed. We give the scaling laws of the multiple-element switch systems, which allow the expansion of the system to a higher power level. We present a novel overmoded design for the circular waveguide three-port network and the associated circular-to-rectangular mode-converter. We also detail the design and synthesis process of …