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A permanent-magnet rotor for a high-temperature superconducting bearing

Description: Design, fabrication, and performance, of a 1/3-m dia., 10-kg flywheel rotor with only one bearing is discussed. To achieve low-loss energy storage, the rotor`s segmented-ring permanent-magnet (PM) is optimized for levitation and circumferential homogeneity. The magnet`s carbon composite bands enable practical energy storage.
Date: July 1, 1995
Creator: Mulcahy, T.M.; Hull, J.R.; Uherka, K.L.; Abboud, R.G.; Wise, J.H. & Carnegie, D.W.
Partner: UNT Libraries Government Documents Department

Overall design concepts for the APS storage ring machine protection system

Description: The basic design and status of the machine protection system for the Advanced Photon Source (APS) storage ring are discussed. The machine is passively safe to the bending magnet sources, but the high power of the insertion devices requires missteering conditions to be identified and the beam aborted in less than one millisecond. The basic aspects of waterflow, temperature, beam position, etc. monitoring are addressed. Initial commissioning of subsystems and sensors is statused.
Date: July 1, 1995
Creator: Lumpkin, A.; Fuja, R.; Votaw, A.; Wang, X.; Shu, D.; Stepp, J. et al.
Partner: UNT Libraries Government Documents Department

Cooling the APS storage ring radio-frequency accelerating cavities: Thermal/stress/fatigue analysis and cavity cooling configuration

Description: The 7-GeV Advanced Photon Source positron storage ring requires sixteen separate 352-MHz radio-frequency (rf) accelerating cavities. Cavities are installed as groups of four, in straight sections used elsewhere for insertion devices. They occupy the first such straight section after injection, along with the last three just before injection. Cooling is provided by a subsystem of the sitewide deionized water system. Pumping equipment is located in a building directly adjacent to the accelerator enclosure. A prototype cavity was fabricated and tested where cooling was via twelve 19-mm-diameter [3/4 in] brazed-on tubes in a series-parallel flow configuration. Unfortunately, the thermal contact to some tubes was poor due to inadequate braze filler. Here, heat transfer studies, including finite-element analysis and test results, of the Advanced Photon Source (APS) storage ring 352-MHz rf accelerating cavities are described. Stress and fatigue life of the copper are discussed. Configuration of water cooling is presented.
Date: June 1, 1995
Creator: Primdahl, K. & Kustom, R.
Partner: UNT Libraries Government Documents Department

Expansion joint for guideway for magnetic levitation transportation system

Description: An expansion joint that allows a guideway of a magnetic levitation transportation system to expand and contract while minimizing transients occurring in the magnetic lift and drag forces acting on a magnetic levitation vehicle traveling over the joint includes an upper cut or recess extending downwardly from the upper surface of the guideway and a non-intersecting lower cut or recess that extends upwardly from the lower surface of the guideway. The sidewalls of the cuts can be parallel to each other and the vertical axis of the guideway; the depth of the lower cut can be greater than the depth of the upper cut; and the overall combined lengths of the cuts can be greater than the thickness of the guideway from the upper to lower surface so that the cuts will overlap, but be spaced apart from each other. The distance between the cuts can be determined on the basis of the force transients and the mechanical behavior of the guideway. A second pair of similarly configured upper and lower cuts may be disposed in the guideway; the expansion joint may consist of two upper cuts and one lower cut; or the cuts may have non-parallel, diverging sidewalls so that the cuts have a substantially dove-tail shape.
Date: December 31, 1991
Creator: Rossing, T.D.
Partner: UNT Libraries Government Documents Department

Positron focusing in the Advanced Photon Source (APS) linear accelerator

Description: Positrons are created by a bremsstrahlung shower process, and are therefore produced with broad divergence and a large energy spread. The e{sup +}/e{sup {minus}} conversion ratio is on the order of 1/200, so the positron focusing system is critical to ensure good positron capture and transport efficiency. The positron focusing system is described, and functions of the different magnetic elements are discussed. Some improvements to the focusing system are suggested, although the linac`s design positron intensity of 8 mA has already been achieved.
Date: July 1, 1995
Creator: Qian, Y.L. & White, M.
Partner: UNT Libraries Government Documents Department

Automated laser scatter detection of surface and subsurface defects in Si{sub 3}N{sub 4} components

Description: Silicon Nitride (Si{sub 3}N{sub 4}) ceramics are currently a primary material of choice to replace conventional materials in many structural applications because of their oxidation resistance and desirable mechanical and thermal properties at elevated temperatures. However, surface or near-subsurface defects, such as cracks, voids, or inclusions, significantly affect component lifetimes. These defects are currently difficult to detect, so a technique is desired for the rapid automated detection and quantification of both surface and subsurface defects. To address this issue, the authors have developed an automated system based on the detection of scattered laser light which provides a 2-D map of surface or subsurface defects. This system has been used for the analysis of flexure bars and button-head tensile rods of several Si{sub 3}N{sub 4} materials. Mechanical properties of these bars have also been determined and compared with the laser scatter results.
Date: June 1995
Creator: Steckenrider, J. S.
Partner: UNT Libraries Government Documents Department

Comparison of the FRM-II HEU design with an alternative LEU design

Description: The FRM-II reactor design of the Technical University of Munich has a compact core that utilizes fuel plates containing highly-enriched uranium (HEU, 93%). This paper presents an alternative core design utilizing low-enriched uranium (LEU, <20%) silicide fuel with 4.8 g/cm{sup 3} that provides nearly the same neutron flux for experiments as the HEU design, but has a less favorable fuel cycle economy. If an LEU fuel with a uranium density of 6.0 - 6.5 g/cm{sup 3} were developed, the alternative design would provide the same neutron flux and use the same number of cores per year as the HEU design. The results of this study show that there are attractive possibilities for using LEU fuel instead of HEU fuel in the FRM-II. Further optimization of the LEU design and near-term availability of LEU fuel with a uranium density greater than 4.8 g/cm{sup 3} would enhance the performance of the LEU core. The RERTR Program is ready to exchange information with the Technical University of Munich to resolve any differences that may exist and to identify design modifications that would optimize reactor performance utilizing LEU fuel.
Date: December 1, 1995
Creator: Mo, S.C.; Hanan, N.A. & Matos, J.E.
Partner: UNT Libraries Government Documents Department

Ionic conductors for solid oxide fuel cells

Description: An electrolyte that operates at temperatures ranging from 600{degree}C to 800{degree}C is discussed. The electrolyte conducts charge ionically as well as electronically. The ionic conductors include molecular framework structures having planes or channels large enough to transport oxides or hydrated protons and having net-positive or net-negative charges. Representative molecular framework structures include substituted aluminum phosphates, orthosilicates, silicoaluminates, cordierites, apatites, sodalites, and hollandites.
Date: December 31, 1991
Creator: Krumpelt, M.; Bloom, I.D.; Pullockaran, J.D. & Myles, K.M.
Partner: UNT Libraries Government Documents Department

A portable concentrator for processing plutonium containing solutions

Description: This report describes a horizontal, compact agitated-film concentrator called a Rototherm, manufactured by Artisan Industries, Inc. which can be used to process aqueous solutions of radioactive wastes containing plutonium. The unit is designed to concentrate liquid streams to a high-solid content slurry.
Date: December 1, 1995
Creator: Chamberlain, D.B.; Conner, C. & Chen, L.
Partner: UNT Libraries Government Documents Department

Feasibility study of a 1-MW pulsed spallation source

Description: A feasibility study of a 1-MW pulsed spallation source based on a rapidly cycling proton synchrotron (RCS) has been completed. The facility consists of a 400-MeV HP{sup -} linac, a 30-Hz RCS that accelerates the 400-MeV beam to 2 GeV, and two neutron-generating target stations. The design time-averaged current of the accelerator system is 0.5 mA, or 1.04{times}1014 protons per pulse. The linac system consists of an H{sup -}ion source, a 2-MeV RFQ, a 70-MeV DTL and a 330-MeV CCL. Transverse phase space painting to achieve a Kapchinskij-Vladimirskij (K-V) distribution of the injected particles in the RCS is accomplished by charge exchange injection and programming of the closed orbit during injection. The synchrotron lattice uses FODO cells of {approx}90{degrees} phase advance. Dispersion-free straight sections are obtained by using a missing magnet scheme. Synchrotron magnets are powered by a dual-frequency resonant circuit that excites the magnets at a 20-Hz rate and de-excites them at a 60-Hz rate, resulting in an effective rate of 30 Hz, and reducing the required peak rf voltage by 1/3. A key feature, of the design of this accelerator system is that beam losses are from injection to extraction, reducing activation to levels consistent with hands-on maintenance. Details of the study are presented.
Date: December 31, 1995
Creator: Cho, Y.; Chae, Y.C. & Crosbie, E.
Partner: UNT Libraries Government Documents Department

The Analytical Labortory sample tracking and reporting system

Description: Regulatory and project requirements stipulate that samples submitted for chemical/physical analysis be owed throughout the analytical process. The Analytical Laboratory (AL) began tracking sample request information electronically using a simple dBASE{trademark} database in 1992. In mid 1993, AL chemists formed a committee to determine the software requirements for a formal sample tracking system. The requirements were outlined for a multi-user FoxPro{trademark} application which tracked sample logins, login templates, worksheets, and sample results and also provided standardized reporting capabilities. The Analytical Laboratory Sample Tracking and Reporting System became available to AL chemists and management in February, 1994. Chemists now had quick, easy access to organized and readable sample data. Up to date, on-line access to sample status information also benefitted AL management. The ability to closely monitor samples decreased sample process time. AL customers also benefitted by receiving standardized Final reports for their samples. Eventually, system performance began to deteriorate as the database grew and network traffic increased. To improve performance, ANL-W Information Services recommended upgrading the system. Upgrading to a fully relational, client/server Oracle{trademark} database accessed from a front-end application developed using Visual Basio{trademark}, one of the many Graphical User Interface (GUI) design tools available today, would improve performance times by greater than 50%. The move to Oracle would improve throughput times of transactions and employ a more efficient use of resources. Visual Basic front-and application development began in May, 1995. In October 1995, the first prototype of the Visual Basic application was made available for testing. AL users were pleased with the added ease-of-use the GUI interface provided. The production version is scheduled for release mid May, 1996.
Date: June 1, 1996
Creator: Colvin, W.J.
Partner: UNT Libraries Government Documents Department

Intense Pulsed Neutron Source: Progress report 1991--1996. 15. Anniversary edition -- Volume 1

Description: The 15th Anniversary Edition of the IPNS Progress Report is being published in recognition of the Intense Pulsed Neutron Source`s first 15 years of successful operation as a user facility. To emphasize the importance of this milestone, the authors have made the design and organization of the report significantly different from previous IPNS Progress Reports. This report consists of two volumes. For Volume 1, authors were asked to prepare articles that highlighted recent scientific accomplishments at IPNS, from 1991 to present; to focus on and illustrate the scientific advances achieved through the unique capabilities of neutron studies performed by IPNS users; to report on specific activities or results from an instrument; or to focus on a body of work encompassing different neutron-scattering techniques. Articles were also included on the accelerator system, instrumentation, computing, target, and moderators. A list of published and ``in press` articles in journals, books, and conference proceedings, resulting from work done at IPNS since 1991, was compiled. This list is arranged alphabetically according to first author. Publication references in the articles are listed by last name of first author and year of publication. The IPNS experimental reports received since 1991 are compiled in Volume 2. Experimental reports referenced in the articles are listed by last name of first author, instrument designation, and experiment number.
Date: May 1, 1996
Creator: Marzec, B.
Partner: UNT Libraries Government Documents Department

Object database standards, persistence specifications, and physics data

Description: Designers of data systems for next-generation physics experiments face a bewildering array of potential paths. On the one hand, object data base technology is quite promising, and standardization efforts are underway in this arena. On another, lightweight object managers may offer greater potential for delivering the high performance needed from petabyte-scale data stores, and may allow more efficient tailoring to specific parallel and distributed environments, as well as to multilevel storage. Adding to the confusion is the evolution of persistence services specifications such as those promulgated by the Object Management Group (OMG). In this paper, we describe what we have learned in efforts to implement a physics data store using several of these technologies, including a lightweight object persistence manager aiming at plug-and-play with object databases, and a trial implementation of the OMG Persistent Data Services Direct Access protocol.
Date: December 31, 1995
Creator: Malon, D.M.; May, E.N.; Grossman, R.L.; Day, C.T. & Quarrie, D.R.
Partner: UNT Libraries Government Documents Department

High energy resolution inelastic x-ray scattering at the SRI-CAT

Description: This report is a combination of vugraphs and two papers. The vugraphs give information on the beamline at the APS for IXS and the science addressable by IXS. They also cover the 10 milli-eV resolution spectrometer and the 200 milli-eV resolution spectrometer. The first paper covers the performance of the focusing Ge(444) backscattering analyzers for the inelastic x-ray scattering. The second paper discusses inelastic x-ray scattering from TiC and Ti single crystals.
Date: August 1, 1996
Creator: Macrander, A.T.
Partner: UNT Libraries Government Documents Department

Results of design calculations for the modulator of the crossed field undulator device

Description: The modulator is a five pole wiggler with a fixed 5 cm gap. In the current design, the modulator is oriented so that the magnetic field in the device is parallel to the field in one of the undulators. The two end poles have no coil and are only half as thick as the inner poles. The end poles serve as field clamps that reduce the stray field of the modulator and the sextupole coefficient of the field integral. The center pole and the two side poles can be energized with coils. As long as the permeability is large enough within the steel the current in the center coil should be twice the current in a side coil to avoid steering the electron beam. Therefore, if the center coil has twice as many turns as the side coil, the magnet can be driven by one power supply.
Date: August 1, 1990
Creator: Sovay, R.
Partner: UNT Libraries Government Documents Department

A front end design for the advanced photon source

Description: X-ray sources on next generation low emittance/high brilliance synchrotrons such as the 7-GeV Advanced Photon Source (APS)(1) have unique properties which directly affect the design of the front end of the beam line. The most striking of these are the large peak photon power densities expected for the insertion device (ID) x-ray sources. Undulators, for example, can have highly peaked photon power distributions with central densities approaching 300 kW/mrad{sup 2}. Large power distributions can also be expected for some of the high critical energy wigglers. Front end components which intercept the photon beam produced by IDs must be able to absorb and safety dissipate the heat loads associated with their power distributions. In addition, detection of the position of the photon beam in some cases requires a precision in the range of a few microns. The information from such photon beam monitors is used primarily in the particle beam control loop in order to maintain the position and take-off angle of the particle beam within some fraction of the beam size and angular divergence dictated by the emittance of the lattice. In most cases, these photon beam detectors must function in the high flux environment of the x-ray beam.
Date: April 1, 1988
Creator: Viccaro, P.J.
Partner: UNT Libraries Government Documents Department

Ceramic membranes for partial oxygenation of hydrocarbon fuels to high-value-added products

Description: This report describes the design of a membrane reactor for converting methane into value added products. The design includes an outer tube of perovskite which contacts air, an inner tube of zirconium oxide which contacts methane, and a bonding layer of a mixture of zirconium oxide and perovskite.
Date: December 31, 1994
Creator: Balachandran, U.; Dusek, J.T.; Kleefisch, M.S. & Kobylinski, T.P.
Partner: UNT Libraries Government Documents Department

Argonne-West facility requirements for a radioactive waste treatment demonstration

Description: At Argonne National Laboratory-West (ANL-W), near Idaho Falls, Idaho, facilities that were originally constructed to support the development of liquid-metal reactor technology are being used and/or modified to meet the environmental and waste management research needs of DOE. One example is the use of an Argonne-West facility to conduct a radioactive waste treatment demonstration through a cooperative project with Science Applications International Corporation (SAIC) and Lockheed Idaho Technologies Company. The Plasma Hearth Process (PBP) project will utilize commercially-adapted plasma arc technology to demonstrate treatment of actual mixed waste. The demonstration on radioactive waste will be conducted at Argonne`s Transient Reactor Test Facility (TREAT). Utilization of an existing facility for a new and different application presents a unique set of issues in meeting applicable federal state, and local requirements as well as the additional constraints imposed by DOE Orders and ANL-W site requirements. This paper briefly describes the PHP radioactive demonstrations relevant to the interfaces with the TREAT facility. Safety, environmental design, and operational considerations pertinent to the PHP radioactive demonstration are specifically addressed herein. The personnel equipment, and facility interfaces associated with a radioactive waste treatment demonstration are an important aspect of the demonstration effort. Areas requiring significant effort in preparation for the PBP Project being conducted at the TREAT facility include confinement design, waste handling features, and sampling and analysis considerations. Information about the facility in which a radioactive demonstration will be conducted, specifically Argonne`s TREAT facility in the case of PHP, may be of interest to other organizations involved in developing and demonstrating technologies for mixed waste treatment.
Date: March 1, 1995
Creator: Dwight, C.C.; Felicione, F.S.; Black, D.B.; Kelso, R.B. & McClellan, G.C.
Partner: UNT Libraries Government Documents Department

Experimental results with cryogenically cooled, thin, silicon crystal x-ray monochromators on high-heat-flux beamlines

Description: A novel, silicon crystal monochromator has been designed and tested for use on undulator and focused wiggler beamlines at third-generation synchrotron sources. The crystal utilizes a thin, partially transmitting diffracting element fabricated within a liquid-nitrogen cooled, monolithic block of silicon. This report summarizes the results from performance tests conducted at the European Synchrotron Radiation Facility (ESRF) using a focused wiggler beam and at the Advanced Photon Source (APS) on an undulator beamline. These experiments indicate that a cryogenic crystal can handle the very high power and power density x-ray beams of modem synchrotrons with sub-arcsec thermal broadening of the rocking curve. The peak power density absorbed on the surface of the crystal at the ESRF exceeded go W/mm{sup 2} with an absorbed power of 166 W, this takes into account the spreading of the beam due to the Bragg angle of 11.4{degrees}. At the APS, the peak heat flux incident on the crystal was 1.5 W/mA/mm{sup 2} with a power of 6.1 W/mA for a 2.0 H x 2.5 V mm{sup 2} beam at an undulator gap of 11.1 mm and stored current up to 96 mA.
Date: August 1, 1996
Creator: Rogers, C.S.; Mills, D.M.; Lee, W.K.; Fernandez, P.B. & Graber, T.
Partner: UNT Libraries Government Documents Department

A study of beam chopping options for the ATLAS Positive Ion Linac

Description: Unbunched beam components from the injection beam bunching system must be removed prior to acceleration in the ATLAS Positive Ion Injector Linac (PII). A sine wave chopper has been used for this purpose up to now. Such a device can have a significant detrimental effect on the longitudinal and transverse beam emittance of heavy-ion beams which can be sufficiently severe to limit the overall beam quality from the ATLAS accelerator. A study of the optimum chopper configuration and chopper type was undertaken as part of a new ion source project for ATLAS. A transmission line chopper and a two harmonic chopper were investigated as alternatives to the conventional sine wave chopper. This paper reports the results of that investigation and discusses the design of the selected transmission line chopper.
Date: October 1, 1996
Creator: Pardo, R.C.; Bogaty, J.M. & Clifft, B.E.
Partner: UNT Libraries Government Documents Department

IPNS upgrade: A feasibility study

Description: Many of Argonne National Laboratory`s (ANL`s) scientific staff members were very active in R&D work related to accelerator-based spoliation sources in the 1970s and early 1980s. In 1984, the Seitz/Eastman Panel of the National Academy of Sciences reviewed U.S. materials science research facilities. One of the recommendations of this panel was that the United States build a reactor-based steady-state source, the Advanced Neutron Source (ANS), at Oak Ridge National Laboratory. Subsequently, R&D activities related to the design of an accelerator-based source assumed a lower priority. The resumption of pulsed-source studies in this country started simultaneously with design activities in Europe aimed at the European Spallation Source (ESS). The European Community funded a workshop in September 1991 to define the parameters of the ESS. Participants in this workshop included both accelerator builders and neutron source users. A consortium of European countries has proposed to build a 5-MW pulsed source, and a feasibility study is currently under way. Soon after the birth of the ESS, a small group at ANL set about bringing themselves up to date on pulsed-source information since 1984 and studied the feasibility of upgrading ANL`s Intense Pulsed Neutron Source (IPNS) to 1 MW by means of a rapidly cycling synchrotron that could be housed, along with its support facilities, in existing buildings. In early 1993, the Kohn panel recommended that (1) design and construction of the ANS should be completed according to the proposed project schedule and (2) development of competitive proposals for cost-effective design and construction of a 1-MW pulsed spallation source should be authorized immediately.
Date: April 1, 1995
Partner: UNT Libraries Government Documents Department

The Advanced Photon Source (APS) linear accelerator as a source of slow positrons

Description: The Advanced Photon Source linear accelerator (linac) system consists of a 200-MeV, 2856-MHz S-band electron linac, a 2-radiation-length-thick tungsten target for positron production, and a 450-MeV positron linac. The linac is briefly described, and some possibilities for its use as a slow positron source are discussed.
Date: September 1, 1996
Creator: White, M.M. & Lessner, E.S.
Partner: UNT Libraries Government Documents Department

Current status of ATLAS and proposed expansion to an Exotic Beam Facility

Description: The Argonne Tandem Linear Accelerator System (ATLAS) has been operating on a twenty-four hour, seven days a week schedule since the beginning of Fiscal Year 1994. Twenty-six different ion species ran during this period in 71 separate experiments. During the past year, there have been many projects undertaken to improve operation efficiency and upgrade various accelerator systems. There is also a new ECR ion source construction project underway. This paper covers, linac operation and new tuning techniques, the second generation ECR source construction project, the refrigerator system upgrade, an upgrade to the control system. Also described is a future expansion of ATLAS as an Exotic Beam Facility. ATLAS is a world class heavy ion accelerator with an estimated value of approximately $80 million. A concept that would utilize ATLAS as the foundation for a facility to generate and accelerate radioactive beams is briefly discussed.
Date: December 31, 1995
Creator: Zinkann, G.P.; Billquist, J. & Bogaty, J.
Partner: UNT Libraries Government Documents Department

The BUG BITBUS Universal Gateway

Description: The BITBUS Universal Gateway (BUG) provides a unique, cost effective solution to many different computer interface problems. Each BUG node, utilizing ``on board`` intelligence, has the ability to provide a communication link between BITBUS protocol and other computer-signal interfaces. Among them, IEEE-488, RS232, and raw analog and binary signal 1/0. BITBUS is a multidrop, multinode link with the ability to communicate over great distances. By using this method of signal transfer, along with the communication conversion ability of the BUG, one could accomplish such things as the ability to run IEEE-488 instruments over great distances, extend a multidrop links to RS232 instruments, and provide a convenient interface point for remote analog and binary 1/0 signals, all on one homogeneous network. The BUG not only provides this through the wired ``twisted pair`` standard of BITBUS, but extends the ability to fiber optic communications for signal transfer over extreme distances and through electrically ``noisy`` environments.
Date: February 1, 1996
Creator: Nawrocki, G.
Partner: UNT Libraries Government Documents Department