States

The Residual Tune Splitting due to Linear Coupling – Theory and Correction (open access)

The Residual Tune Splitting due to Linear Coupling – Theory and Correction

None
Date: June 1, 1991
Creator: Parzen, G.
Object Type: Report
System: The UNT Digital Library
The Astromag Superconducting Magnet Facility Configured for a FreeFlying Satellite (open access)

The Astromag Superconducting Magnet Facility Configured for a FreeFlying Satellite

ASTROMAG is a particle astrophysics facility that was originally configured for the Space Station. The heart of the ASTROMAG facility is a large superconducting magnet which is cooled using superfluid helium. The task of resizing the facility so that it will fly in a satellite in. a high angle of inclination orbit is driven by the launch weight capability of the launch rocket and the desire to be able to do nearly the same physics as the Space Station version of ASTROMAG. In order to reduce the launch weight, the magnet and its cryogenic system had to be downsized, yet the integrated field generated by the magnet in the particle detectors has to match the Space Station version of the magnet. The use of aluminum matrix superconductor and oriented composite materials in the magnet insulation permits one to achieve this goal. The net magnetic dipole moment from the ASTROMAG magnet must be small to minimize the torque due to interaction with the earth's magnetic field. The ASTROMAG magnet consists of identical two coils 1.67 meters apart. The two coils are connected in series in persistent mode. Each coil is designed to carry 2.34 million ampere turns. Both coils are mounted …
Date: June 1, 1991
Creator: Green, M. A. & Smoot, George F.
Object Type: Article
System: The UNT Digital Library
Measurements of Retractable Gas-Cooled 6061 Aluminum ElectricalLeads Operating in a Vacuum (open access)

Measurements of Retractable Gas-Cooled 6061 Aluminum ElectricalLeads Operating in a Vacuum

To charge and discharge the ASTROMAG superconducting magnet in space requires retractable gas-cooled leads which must operate in a vacuum. This report describes the design and test of 500 ampere retractable gas-cooled leads made from 6061-T4 aluminum tubes. Aluminum is attractive for gas-cooled electrical leads in space because of its low mass density and the desire for short leads. Initial tests showed that retractable gas-cooled leads could operate in a vacuum from a source of normal helium. The pressure drop through the leads was low enough to permit a superconducting magnet to be charged and discharged while the leads vent into space. The leads were stable at currents above 700 amperes. The voltage drop across the contact between the upper and lower leads was as low as 1.2 mV per lead out of a total voltage drop of 42 mV per lead when the leads carried 714 amperes. The gas required for cooling was comparable to the more conventional copper gas-cooled current leads. In a second test seven months later. The contact resistance between the lead sections had increased considerably. In the second test, the contact resistance was repeatable for one lead but not for the other.
Date: June 1, 1991
Creator: Green, M. A.; Aguiar, H.; Bensadoun, M. J.; Gibson, J. H.; Heine, D. L.; Levin, S. et al.
Object Type: Article
System: The UNT Digital Library
Solitons and Particle Beams (open access)

Solitons and Particle Beams

Since space charge waves on a particle beam exhibit both dispersive and nonlinear character, soliton-like behavior is possible. Some theoretical aspects of dispersive, nonlinear wave propagation in high brightness beams are discussed. Numerical examples for realizable beams are presented, and issues for future studies are noted.
Date: June 1, 1991
Creator: Bisognano, Joseph
Object Type: Article
System: The UNT Digital Library
Neutron and Gamma Boundary Radiation Monitoring at CEBAF (open access)

Neutron and Gamma Boundary Radiation Monitoring at CEBAF

None
Date: June 1, 1991
Creator: Pollock, E.; Stapleton, Geoffrey; Stapleton, Geoffrey & Letizia, R.
Object Type: Report
System: The UNT Digital Library
Radiation Studies in the Antiproton Source (open access)

Radiation Studies in the Antiproton Source

Experiment E760 has a lead glass (Pb-G) calorimeter situated in the antiproton source tunnel in the accumulator ring at location A50. This location is exposed to radiation from several sources during antiproton stacking operations. A series of radiation studies has been performed over the last two years to determine the sources of this radiation and as a result, some shielding has been installed in the antiproton source in order to protect the lead glass from radiation damage.
Date: June 10, 1991
Creator: Church, Mike
Object Type: Report
System: The UNT Digital Library
Power Handling Upgrade of Debuncher Stochastic Cooling Kicker Tanks (open access)

Power Handling Upgrade of Debuncher Stochastic Cooling Kicker Tanks

The Debuncher Stochastic Cooling Power Upgrade tripled the number of TWTs from 16 to 48. The power desired for each TWT is about 120 W. The debuncher stochastic cooling system contains 6 kicker tanks (4 short tanks, 2 long tanks) with a total number of 64 microwave feedthroughs. Thus, the power per feedthrough increased from 30W to 90 W as a result of the upgrade. The kicker array inside the vacuum tank is connected to the microwave feedthrough on the vacuum flange by means of a rigid 0.25-inch diameter coaxial cable which is 12-inch long. With 90 W flowing through the coax, the amount of power dissipated is 2.5 W. A lab test on a single debuncher kicker tank showed that this power dissipation caused the temperature of the coaxial cable to rise to greater than 175 C. At this point the Teflon dielectric of the coax and the solder joints in the coax might seriously degrade. As a temporary stop-gap solution, transistor heat sinks were placed around the outside of the coaxial cable. (The amount of heat sinks need for all the cables was 3400.) The primary function of the transistor heat sinks around the coaxial cable was to …
Date: June 1, 1991
Creator: McGinnis, D.
Object Type: Report
System: The UNT Digital Library
TACB Bulletin, Number 2, Summer 1991 (open access)

TACB Bulletin, Number 2, Summer 1991

Newsletter of the Texas Air Control Board including information about the Board as well as news, events, and other relevant information related to air quality in Texas.
Date: 1991-06/1991-08
Creator: Texas Air Control Board
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Texas Real Estate Center Trends, Volume 4, Number 10, June 1991 (open access)

Texas Real Estate Center Trends, Volume 4, Number 10, June 1991

Monthly report of the Texas A & M University Real Estate Center on statistics, recent news, and developments related to real estate.
Date: June 1991
Creator: Texas A & M University. Real Estate Center.
Object Type: Report
System: The Portal to Texas History
The International Coal Statistics Data Base program maintenance guide (open access)

The International Coal Statistics Data Base program maintenance guide

The International Coal Statistics Data Base (ICSD) is a microcomputer-based system which contains information related to international coal trade. This includes coal production, consumption, imports and exports information. The ICSD is a secondary data base, meaning that information contained therein is derived entirely from other primary sources. It uses dBase III+ and Lotus 1-2-3 to locate, report and display data. The system is used for analysis in preparing the Annual Prospects for World Coal Trade (DOE/EIA-0363) publication. The ICSD system is menu driven and also permits the user who is familiar with dBase and Lotus operations to leave the menu structure to perform independent queries. Documentation for the ICSD consists of three manuals -- the User's Guide, the Operations Manual, and the Program Maintenance Manual. This Program Maintenance Manual provides the information necessary to maintain and update the ICSD system. Two major types of program maintenance documentation are presented in this manual. The first is the source code for the dBase III+ routines and related non-dBase programs used in operating the ICSD. The second is listings of the major component database field structures. A third important consideration for dBase programming, the structure of index files, is presented in the listing …
Date: June 1, 1991
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Evaluation of weldments in Type 21-6-9 stainless steel for Compact Ignition Tokamak structural applications: Phase 1 (open access)

Evaluation of weldments in Type 21-6-9 stainless steel for Compact Ignition Tokamak structural applications: Phase 1

Primary design considerations for the Compact Ignition Tokamak toroidal field-coil cases are yield strength and toughness in the temperature range from 77 to 300 K. Type 21-6-9 stainless steel, also still known by its original Armco Steel Company trade name Nitronic 40, is the proposed alloy for this application. It has high yield strength and usually adequate base metal toughness, but weldments in thick sections have not been adequately characterized in terms of mechanical properties or hot-cracking propensity. In this study, weldability of the alloy in heavy sections and the mechanical properties of the resultant welds were investigated including tensile yield strength and Charpy V-notch toughness at 77 K and room temperature. Weldments were made in four different base metals using seven different filler metals. None of the weldments showed any indication of hot-cracking problems. All base metals, including weldment heat-affected zones, were found to have adequate strength and impact toughness at both test temperatures. Weld metals, on the other hand, except ERNiCr-3 and ENiCrFe-3 had impact toughnesses of less than 67 J at 77 K. Inconel 82 had an average weld metal impact toughness of over 135 J at 77 K, and although its strength at 77 K is …
Date: June 1, 1991
Creator: Alexander, D. J.; Goodwin, G. M. & Bloom, E. E.
Object Type: Report
System: The UNT Digital Library
Process and analytical studies of enhanced low severity co-processing using selective coal pretreatment (open access)

Process and analytical studies of enhanced low severity co-processing using selective coal pretreatment

This report describes progress on research during the eleventh quarter of this contract dealing with applications of coal pretreatment techniques in coal/oil co-processing and direct hydroliquefaction. The objectives of the project are to investigate various coal pretreatment techniques and to determine the effect of these pretreatment procedures on the reactivity of the coal. Reactivity enhancement will be evaluated under both direct hydroliquefaction and co-processing conditions. Coal conversion utilizing low rank coals and low and severity conditions (reaction temperatures generally less than 350{degrees}C) is the primary focus of the liquefaction experiments, as it is expected that the effect of pretreatment conditions and the attendant reactivity enhancement will be greatest for these coals and at these conditions. This document presents a summary of results for the first set of a series of runs intended to simulate operation of a two-stage integrated liquefaction reactor train. These studies were designed to investigate the effect of the severity of the first stage liquefaction process on the required severity and resulting yields from the second stage. Process conditions were varied between thermal and catalytic for both stages, and from temperatures of 350 to 400{degrees}C at a nominal residence time of 30 minutes. These data will provide …
Date: 1991-06~
Creator: Baldwin, R. M.; Gaur, S. & Miller, R. L.
Object Type: Report
System: The UNT Digital Library
Test results of BNL built 40-mm aperture, 17-m-long SSC collider dipole magnets (open access)

Test results of BNL built 40-mm aperture, 17-m-long SSC collider dipole magnets

Eleven 17 m long, 40 mm aperture SSC R D superconducting collider dipole magnets, built at BNL, have been extensively tested at BNL and Fermilab during 1990--91. Quench performance of these magnets and details of their mechanical behavior are presented. 7 refs., 5 figs.
Date: June 1, 1991
Creator: Kuzminski, J.; Bush, T.; Coombes, R.; Devred, A.; DiMarco, J.; Goodzeit, C. et al.
Object Type: Article
System: The UNT Digital Library
Research for Electric Energy Systems (open access)

Research for Electric Energy Systems

This report documents the technical progress in investigations. The first investigation is concerned with the measurement of magnetic fields in support of epidemiogical and in vitro studies of biological field effects. NIST cohosted a workshop on exposure and biological parameters that should be considered during the vitro studies with extremely low frequency (ELF) magnetic and electric fields. Also, equations were developed to predict the magnetic field in a parallel plate magnetic field exposure system. The second investigation is concerned with two different activities: the detection of trace levels of S{sub 2}F{sub 10} in SF{sub 6} and the development of an improved stochastic analyzer for pulsating phenomena (SAPP). The detection of S{sub 2}F{sub 10} in the presence of SF{sub 6} using mass-spectrometric detection coupled to a gas chromatograph is difficult because of the similar mass spectra. A technique is described that enables the detection of S{sub 2}F{sub 10} in gaseous SF{sub 6} down to the ppb level using a modified gas chromatograph-mass spectrometer. The new system was applied to an investigation of the stochastic behavior of negative corona (Trichel pulses) and the effect of a dielectric barrier on these discharges. The third investigation is concerned with breakdown and prebreakdown phenomena in …
Date: June 1, 1991
Creator: Anderson, W.E. (ed.)
Object Type: Report
System: The UNT Digital Library
Mechanical compaction of Waste Isolation Pilot Plant simulated waste (open access)

Mechanical compaction of Waste Isolation Pilot Plant simulated waste

The investigation described in this report acquired experimental information about how materials simulating transuranic (TRU) waste compact under axial compressive stress, and used these data to define a model for use in the Waste Isolation Pilot Plant (WIPP) disposal room analyses. The first step was to determine compaction curves for various simultant materials characteristic of TRU waste. Stress-volume compaction curves for various combinations of these materials were than derived to represent the combustible, metallic, and sludge waste categories. Prediction of compaction response in this manner is considered essential for the WIPP program because of the difficulties inherent in working with real (radioactive) waste. Next, full-sized 55-gallon drums of simulated combustible, metallic, and sludge waste were axially compacted. These results provided data that can be directly applied to room consolidation and data for comparison with the predictions obtained in Part 1 of the investigation. Compaction curves, which represent the combustible, metallic, and sludge waste categories, were determined, and a curve for the averaged waste inventory of the entire repository was derived. 9 refs., 31 figs., 12 tabs.
Date: June 1, 1991
Creator: Butcher, B. M.; Thompson, T. W.; VanBuskirk, R. G. & Patti, N. C.
Object Type: Report
System: The UNT Digital Library
CDFTBL: A statistical program for generating cumulative distribution functions from data (open access)

CDFTBL: A statistical program for generating cumulative distribution functions from data

This document describes the theory underlying the CDFTBL code and gives details for using the code. The CDFTBL code provides an automated tool for generating a statistical cumulative distribution function that describes a set of field data. The cumulative distribution function is written in the form of a table of probabilities, which can be used in a Monte Carlo computer code. A a specific application, CDFTBL can be used to analyze field data collected for parameters required by the PORMC computer code. Section 2.0 discusses the mathematical basis of the code. Section 3.0 discusses the code structure. Section 4.0 describes the free-format input command language, while Section 5.0 describes in detail the commands to run the program. Section 6.0 provides example program runs, and Section 7.0 provides references. The Appendix provides a program source listing. 11 refs., 2 figs., 19 tabs.
Date: June 1, 1991
Creator: Eslinger, P.W. (Pacific Northwest Lab., Richland, WA (United States))
Object Type: Report
System: The UNT Digital Library
Nuclear facility licensing, documentaion, and reviews, and the SP-100 test site experience (open access)

Nuclear facility licensing, documentaion, and reviews, and the SP-100 test site experience

The required approvals and permits to test a nuclear facility are extensive. Numerous regulatory requirements result in the preparation of documentation to support the approval process. The principal regulations for the SP-100 Ground Engineering System (GES) include the National Environmental Policy Act, Clean Air Act, and Atomic Energy Act. The documentation prepared for the SP-100 Nuclear Assembly Test (NAT) included an Environmental Assessment, state permit applications, and Safety Analysis Reports. This paper discusses the regulation documentation requirements and the SP-100 NAT Test Site experience. 12 refs., 2 figs., 2 tabs.
Date: June 1, 1991
Creator: Cornwell, B. C.; Deobald, T. L. & Bitten, E. J.
Object Type: Article
System: The UNT Digital Library
Study of the corrosion rate behavior of ion implanted Fe-based alloys (open access)

Study of the corrosion rate behavior of ion implanted Fe-based alloys

We report on some studies we have made of the time evolution of the corrosion behavior of ion implanted samples of pure iron, medium carbon steel, and 18-8 Cr-Ni stainless steel. Ti, Cr, Ni, Cu, Mo and Yb were implanted at mean ion energies near 100 keV and at doses up to 1 {times} 10{sup 17} cm{sup {minus}2} using a Mevva metal ion implantation facility. A novel feature of this experiment was the simultaneous implantation with several different implanted species. The implanted samples were immersed in sulfuric acid solution at 40{degrees}C and the corrosion monitored as a function of time. The loss in mass was accurately measured using atomic absorption spectroscopy. The functional dependence of the corrosion behavior was established for all samples. The cumulative mass loss Q is given as a function of time t by Q = At{sup N}, where A and N are parameters; thus the corrosion rate V is given by V = ANt{sup N-1}. A is dominated by the initial mass loss and N reflects the long-time corrosion behavior. The values of the parameters A and N were obtained by a least-squares regression for all the samples investigated. We determined that for the samples investigated …
Date: June 1, 1991
Creator: Weiping, Cai; Wei, Tian; Wu Run (Wuhan Iron and Steel Univ., HB (China)); Godechot, X. & Brown, I. (Lawrence Berkeley Lab., CA (United States))
Object Type: Article
System: The UNT Digital Library
Fundamental studies of catalytic gasification (open access)

Fundamental studies of catalytic gasification

Studies of the catalytic steam gasification of carbon solids continued. In this project a considerable number of important findings have been made. Recently limited experimentation has been carried out on the production of C{sub 2} hydrocarbons from methane in the presence of Ca/K/Ni oxide catalysts and of oxygen, carbon and water. The main finding thus far has been that C{sub 2} yields of 10--13% can be obtained at about 600{degrees}C or 150{degrees} lower temperature than described in the literature for similar yields. Work during this quarter was largely concentrated on oxidative methane coupling. Gasification of a petroleum coke is also discussed. 5 tabs.
Date: June 1, 1991
Creator: Heinemann, H. & Smorjai, G.A.
Object Type: Report
System: The UNT Digital Library
Tests of a model pole assembly for the ALS U5. 0 undulator (open access)

Tests of a model pole assembly for the ALS U5. 0 undulator

The ALS insertion devices must meet very tight requirements in terms of field quality and field strength. Even though the ability to calculate the performance of a hybrid insertion device has improved considerably over the past few years, a model pole was assembled to test the ALS U5.0 undulator geometry and to verify the calculations. The model pole consists of a half period of the periodic structure of the insertion device with mirror plates at the midplane and at the zero-field, half-period planes. A Hall probe was used to measure the vertical component of the field near the midplane of the model as a function of gap and transverse position. Because of the tight field quality requirements the ALS insertion devices are designed to permit several types of correction, including the capability of adding magnetic material or iron at several locations to boost or buck the field. This correction capability was evaluated during our tests. The model is described and details of the test results are discussed, including the fact that the measured peak field is several percent higher than the calculated value, which is based on the measured magnetization of the blocks used in the model. 8 refs., 20 …
Date: June 1, 1991
Creator: Hassenzahl, W.V.; Hoyer, E. (Lawrence Berkeley Lab., CA (United States)) & Savoy, R. (Argonne National Lab., IL (United States))
Object Type: Report
System: The UNT Digital Library
Tank 241-A-105 leak assessment (open access)

Tank 241-A-105 leak assessment

Tank 241-A-105 is one of 149 single shell tanks constructed at Hanford to contain and store highly radioactive wastes originating from the processing of spent nuclear reactor fuel. Radiation detection and temperature monitoring devices installed beneath the tank indicate that several episodes of leakage of waste from the tank have occurred. The aim of this study was to evaluate the previous estimates and reanalyze the data to provide a more accurate estimate of leakage from the tank. The principal conclusions of this study are as follows: Earlier investigators estimated leakage prior to August 1968 at 5,000 to 15,000 gallons. Their estimate appears reasonable. Leakage while the tank was being sluiced (8/68--11/70) probably exceeded 5,000 gallons, but probably did not exceed 30,000 gallons. Insufficient data are available to be more precise. Cooling water added to the tank during the sprinkling phase (11/70 -- 12/78) was approximately 610,000 gallons. Sufficient heat was generated in the tank to evaporate most, and perhaps nearly all, of this water. Radionuclides escaping into the soil under the tank cannot be estimated directly because of many uncertainties. Based on a range of leakage from 10,000 to 45,000 gallons, assumed compositions, and decayed to 1/1/91, radioactivity under the …
Date: June 1, 1991
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Top physics at CDF (open access)

Top physics at CDF

We present here preliminary results of an extension of our already published search for the top quark. The search is based on a data sample collected during the 1988--1989 run of the Fermilab Tevatron Collider corresponding to an integrated luminosity of 4.4 pb {sup {minus}1}. We find no evidence for top quark production and we establish preliminary limits on the t-tbar production cross section as a function of the top mass (M{sub top}) in p-pbar collisions at {radical}s = 1.8 TeV. Using theoretical expectations for this cross-section, we translate these limits into a preliminary lower limit for M{sub top} of 89 Gev/c{sup 2} at the 95% confidence level. 12 refs., 3 figs. (CL)
Date: June 1, 1991
Creator: Campagnari, C.
Object Type: Article
System: The UNT Digital Library
Structural analysis of a reflux pool-boiler solar receiver (open access)

Structural analysis of a reflux pool-boiler solar receiver

Coupled thermal-structural finite element calculations of a reflux pool-boiler solar receiver were performed to characterize the operating stresses and to address issues affecting the service life of the receiver. Analyses performed using shell elements provided information for receiver material selection and design optimization. Calculations based on linear elastic fracture mechanics principles were performed using continuum elements to assess the vulnerability of a seam-weld to fatigue crack growth. All calculations were performed using ABAQUS, a general purpose finite element code, and elements specifically formulated for coupled thermal-structural analysis. Two materials were evaluated: 316L SS and Haynes 230 alloys. The receiver response was simulated for a combination of structural and thermal loads that represent the startup and operating conditions of the receiver. For both materials, maximum stresses in the receiver developed shortly after startup due to uneven temperature distribution across the receiver surface. The largest effective stress was near yield in the 316L SS receiver and below 39 percent of yield in the Haynes 230 receiver. The calculations demonstrated that stress reductions of over 25 percent could be obtained by reducing the aft dome thickness to one closer to the absorber. The fatigue calculations demonstrated that the stress distribution near the seam-weld …
Date: June 1, 1991
Creator: Hoffman, E. L. & Stone, C. M.
Object Type: Report
System: The UNT Digital Library
Radiation effects on structural materials (open access)

Radiation effects on structural materials

This report discusses the following topics on the effect radiation has on thermonuclear reactor materials: Atomic Displacements; Microstructure Evolution; Materials Engineering, Mechanics, and Design; Research on Low-Activation Steels; and Research Motivated by Grant Support.
Date: June 28, 1991
Creator: Ghoniem, N. M.
Object Type: Report
System: The UNT Digital Library