Serial/Series Title
Winter Fuels Report
4
Petroleum Marketing Monthly
3
ARM Facilities Newsletter
2
Fiscal Year 2007
2
Hindered Diffusion of Asphaltenes at Elevated Temperature and Pressure Progress Report
2
Lignite Fuel Enhancement Progress Report
2
Development of Continuous Solvent Extraction Processes for Coal Derived Carbon Products Quarterly Report
1
Enhancement of Equilibrium Shift in Dehydrogenation Reactions Using a Novel Membrane Reactor Semi-Annual Report
1
Fiscal Year 1999
1
Fiscal Year 2000
1
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2,850 Matching Results
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Improvements in the weldability of a superconductor sheath material
This paper investigates the effects of chemistry and heat treatment variation on the 4-K tensile properties of A-286, a candidate sheath material for force-cooled superconductors. Currently, full use of A-286 and similar superalloys is limited by the observed low yield and ultimate tensile strengths in the welded and aged condition. The low strength is shown to be associated with the formation of precipitate-free zones as a result of alloying-element segregation during weld pool solidification. It has been determined that minor modifications of the weld-metal chemistry by the addition of Ti reduce precipitate-free-zone formation, resulting in matching weld-metal and base-plate strengths at 4 K. Furthermore, nucleation of the ..gamma..' hardening phase has been found to be a strong function of temperature and composition. Modified heat-treatment schedules have been determined that are amenable to superconductor fabrication and that resulted in increased weld hardening and improved 4-K tensile properties.
Date:
August 7, 1985
Creator:
Summers, L.T. & Morris, J.W. Jr.
Object Type:
Article
System:
The UNT Digital Library
Calculational tools for the evaluation of nuclear cross-section and spectra data
A technique based on discrete energy levels rather than energy level densities is presented for nuclear reaction calculations. The validity of the technique is demonstrated via theoretical and experimental agreement for cross sections, isomer-ratios and gamma-ray strength functions. 50 refs., 7 figs. (WRF)
Date:
May 7, 1985
Creator:
Gardner, M.A.
Object Type:
Article
System:
The UNT Digital Library
Bates solar industrial process-steam application: preliminary design review
The design is analyzed for a parabolic trough solar process heat system for a cardboard corrugation fabrication facility in Texas. The program is briefly reviewed, including an analysis of the plant and process. The performance modeling for the system is discussed, and the solar system structural design, collector subsystem, heat transport and distribution subsystem are analyzed. The selection of the heat transfer fluid, and ullage and fluid maintenance are discussed, and the master control system and data acquisition system are described. Testing of environmental degradation of materials is briefly discussed. A brief preliminary cost analysis is included. (LEW)
Date:
January 7, 1980
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Automated supernova search
A program is described for development of an automated supernova search based upon complete remote computer control of a telescope and vidicon digital imaging system. (GHT)
Date:
October 7, 1981
Creator:
Colgate, S. A.
Object Type:
Article
System:
The UNT Digital Library
High-field superconducting solenoids for the TIBER II PF (poloidal-field) system
The poloidal-field (PF) coil set for the Tokamak Ignition/Burn Engineering Reactor (TIBER-II) consists of 24 solenoid modules, 16 of which are stacked inside the toroidal-field (TF) system at the center of the machine. These central solenoid modules operate at high-current densities, and maximum fields at the windings approach 14 T. Although TIBER-II is designed for steady-state operation with noninductive current drive, other operating scenarios are also considered. In the pulsed or inductive mode, PF coil currents are ramped to induce plasma current. In this mode, peak fields approaching 14 T appear on the central solenoid modules at the ends of the stack; the required current densities in these modules approach 40 A . mm/sup 2/. The central solenoid modules are layer wound using cable-in-conduit conductor (CICC) with (NbTi)/sub 3/Sn composite strands for improved high-field performance. Layer winding permits grading the conductor for maximum overall winding-pack current density and also results in less wasted space in the radial build of the machine. Cooling connections may be made at each layer of a module as needed. Current leads to the modules are routed through the high-field central bore. The central solenoid modules can easily support the centering load of the PF system, …
Date:
October 7, 1987
Creator:
Kerns, J. A.; Miller, J. R. & Summers, L. T.
Object Type:
Article
System:
The UNT Digital Library
Elastic-wave radiation from spherical sources
The radiation of spherical compressional waves from a spherical cavity in an ideal elastic solid is treated. The equations for the radiation source and field are written in terms of the reduced-displacement potential. The source equation is studied in terms of characteristic frequencies, corresponding periods and wavelengths, and damping. The field equations for the stresses, strains, radial displacement, etc., are reviewed with regard to the transitions between the near and far fields. The natural parameters for defining the dynamic source and field characteristics are 2b/R and b/a in some cases and a/R in others, where a is the compressional-wave velocity, b the shear-wave velocity, and R the cavity radius. Transient solutions for stresses, strains, radial displacement, etc., include damped sinusoidal oscillations. The initial- and final-value theorems for the Laplace transform are used to obtain solutions for tau (reduced time) ..-->.. 0 + (high-frequency, farfield) and tau ..-->.. infinity (zero-frequency, near-field). 14 figures, 4 tables.
Date:
December 7, 1979
Creator:
Rodean, H.C.
Object Type:
Report
System:
The UNT Digital Library
TIBER-II TF (toroidal-field) winding pack design
The superconducting, toroidal-field (TF) coils in the Tokamak Ignition/Burn Engineering Reactor (TIBER II) are designed with cable-in-conduit conductor (CICC) using Nb/sub 3/Sn composite strands. To design the CICC winding pack, we used an optimization technique that maximizes the conductor stability without violating the constraints imposed by the structure, electrical insulation, quench protection, and fabrication technique. Detailed helium-properties codes calculate the heat removal along a flow path, and detailed field calculations determine the temperature, current, and stability margins. The conductor sheath is designed as distributed structure to partially support the combined in-plane and out-of-plane loads generated within the winding pack. Pancakes of the coil are wound, reacted, and insulated before being potted in the case. This design is aggressive but fully consistent with good engineering practice. 5 refs., 4 figs., 2 tabs.
Date:
October 7, 1987
Creator:
Kerns, J. A.; Miller, J. R.; Slack, D. S. & Summers, L. T.
Object Type:
Article
System:
The UNT Digital Library
Geologic and geochemical studies of the New Albany Group (Devonian black shale) in Illinois to evaluate its characteristics as a source of hydrocarbons. Quarterly progress report, October 1-December 31, 1979
This project is a detailed analysis of the lithology, stratigraphy, and structure of the New Albany Group in Illinois to determine those characteristics of lithology, thickness, regional distribution, vertical and lateral variability, and deformation that are most relevant to the occurrence of hydrocarbons. Research is reported for this quarter in the following areas: coordination of stratigraphic maps, mineralogic and petrographic characterization, physical properties of Devonian black shale, quantitative determination of major, minor, and trace elements in shales, inorganic/organic associations of trace elements in black shales, mode of occurrence and relative distribution of hydrocarbon phases in shale, and adsorption/desorption studies of gases through shales. 6 figures, 7 tables. (RWR)
Date:
January 7, 1980
Creator:
Bergstrom, R.E. & Shimp, N.F.
Object Type:
Report
System:
The UNT Digital Library
Design of the D0 overpass dispersion correction
The existing D0 overpass induces a vertical dispersion wave around the Main ring with dispersion amplitudes of around 1.6 to 1.8 m. There are two major reasons to eliminate or reduce vertical dispersion induced by the D0 overpass: to lower the beam momentum dependence on vertical positions which had not existed before the overpass; and to raise the Tevatron luminosity by eliminating the dispersion mismatch between the main Ring and Tevatron. 20 figs., 1 tab.
Date:
October 7, 1987
Creator:
Trbojevic, D.
Object Type:
Report
System:
The UNT Digital Library
Wire-rope emplacement of diagnostics systems
The study reported here was initiated to determine if, with the Cable Downhole System (CDS) currently under development, there is an advantage to using continuous wire rope to lower the emplacement package to the bottom of the hole. A baseline design using two wire ropes as well as several alternatives are discussed in this report. It was concluded that the advantages of the wire-rope emplacement system do not justify the cost of converting to such a system, especially for LLNL's maximum emplacement package weights.
Date:
May 7, 1982
Creator:
Burden, W. L.
Object Type:
Report
System:
The UNT Digital Library
Reel support for wind the magnet of the Mirror Fusion Test Facility
The reel support has three main functions. It must support the reel, which is 134 in. in diameter, 40 in. wide, and stores up to 8,600 ft of superconductor weighing 8,600 lb. It also must serve as a tensioning device for the superconductor, exerting a force of up to 600 lb. Further, the support must move the reel vertically and laterally to facilitate the winding of the magnets. The support has been designed and is now being fabricated. This paper describes the performance requirements of this device and the evolution of design from concept to completion.
Date:
September 7, 1977
Creator:
Ling, R.C.; Chang, Y. & Hunt, L.D.
Object Type:
Article
System:
The UNT Digital Library
Development of Electrochemical Photovoltaic Cells. Third Technical Progress Report, November 1, 1979-January 31, 1980
The development of stable, efficient, electrochemical photovoltaic cells based on silicon and gallium arsenide in non-aqueous electrolyte systems is being investigated. The effect of surface condition of silicon electrodes on electrochemical and physical characteristics has been studied. An electrode-supporting electrolyte interaction in acetonitrile has been identified which leads to etching of the surface. Improved performance can result, which has practical significance. Gallium arsenide electrodes have been electrochemically characterized in cells containing propylene carbonate with a ferrocene/ferricenium redox additive. Degradation of the ferricenium salt under illumination has been investigated. Other redox couples studied to date have not given promising results. Long-term stability experiments have been deferred while a better understanding of electrode behavior is being obtained.
Date:
March 7, 1980
Creator:
Byker, H. J.; Schwerzel, R. E.; Wood, V. E.; Austin, A. E. & Brooman, E. W.
Object Type:
Report
System:
The UNT Digital Library
Batch Kd measurements of nuclides to estimate migration potential at the proposed Waste Isolation Pilot Plant in New Mexico
Laboratory measurements to determine the sorption distribution coefficients, Kd, of radionuclides present in, and potentially leached from, radioactive wastes, in contact with representative geologic media, have been conducted. The nuclides studied include Cs, Sr, Tc, Ru, Sb, Ce, Eu, Pu, Np, Cm, Am, U, and Pa. The crushed rock materials used were from the vicinity of the Waste Isolation Pilot Plant, a project to isolate radioactive wastes in a bedded salt facility, near Carlsbad, New Mexico. Solutions used consist of salt brine and groundwater, specific to the WIPP site, plus distilled water, for laboratory intercomparisons. The batch Kd data reported, plus data from sorption and migration measurements being conducted or planned elsewhere, will be used to evaluate the potential for radionuclide migration from the bedded salt WIPP facility. The data can be used for transport modeling and for safety assessment determinations.
Date:
October 7, 1977
Creator:
Serne, R.J.; Rai, D.; Mason, M.J. & Molecke, M.A.
Object Type:
Report
System:
The UNT Digital Library
Creep of 304 LN and 316 L stainless steels at cryogenic temperatures
Creep behavior of Type 304 LN plate and 316 L shielded-metal-arc (SMA)-deposited stainless weld metal was investigated at 4/sup 0/K. Testing was performed at constant load in a creep machine with a cryostat designed for long-term stability. Both transient and steady-state creep were observed during tests lasting over 2000 hours. Steady-state creep rates were much greater than expected from extrapolations of 300-K creep data. Creep rates on the order of 10/sup -10/ s/sup -1/ were observed at stresses around the yield stress for both materials. The stress exponent under these conditions if approx.2.3. Possible creep mechanisms at this temperature and the impact of these results on the design of engineering structures for long-term structural stability at cryogenic temperatures are discussed.
Date:
August 7, 1985
Creator:
Roth, L. D.; Manhardt, A. E.; Dalder, E. N. C. & Kershaw, R. P., Jr.
Object Type:
Article
System:
The UNT Digital Library
Design of a microwave calorimeter for the microwave tokamak experiment
The initial design of a microwave calorimeter for the Microwave Tokamak Experiment is presented. The design is optimized to measure the refraction and absorption of millimeter rf microwaves as they traverse the toroidal plasma of the Alcator C tokamak. Techniques utilized can be adapted for use in measuring high intensity pulsed output from a microwave device in an environment of ultra high vacuum, intense fields of ionizing and non-ionizing radiation and intense magnetic fields. 16 refs.
Date:
October 7, 1988
Creator:
Marinak, M. (California Univ., Berkeley, CA (USA))
Object Type:
Report
System:
The UNT Digital Library
Some optics alternatives for the FFS
The evolution of the SLC Final Focus System (FFS) has been discussed in the SLC Red Books and various collider notes. Bulos and Brown and Murray were able to achieve small ..beta..'s with large l/sub 1/'s (the distance between the IP and the effective field boundary of the first quad). However, all current solutions which are compatible with the known constraints of the total path length, aperture and spot size require high gradient, superconducting quads. Such quads cannot be expected to provide very good inherent field quality (i.e., without correction windings) but can be expected to be comparatively expensive to build and operate simply. The purpose of this note is to present a more general solution for the FFS telescope which is compatible with the known constraints of detectors, magnet types, available space and the ingoing and outgoing phase space expectations. While a number of different solutions were found, the ones presented provide comparable performance, simpler operation and lower costs. The gradients are sufficiently low to allow the use of conventional electromagnets, intrinsic or cryostable superconducting or rare earth permanent (REP) magnets or any arbitary combination of all of these magnet types. 8 references, 9 figures, 1 table.
Date:
March 7, 1984
Creator:
Spencer, J.E.
Object Type:
Report
System:
The UNT Digital Library
Effective theories and thresholds in particle physics
The role of effective theories in probing a more fundamental underlying theory and in indicating new physics thresholds is discussed, with examples from the standard model and more speculative applications to superstring theory. 38 refs.
Date:
June 7, 1991
Creator:
Gaillard, M. K.
Object Type:
Article
System:
The UNT Digital Library
Slicing of silicon into sheet material. Silicon sheet growth development for the large area silicon sheet task of the Low Cost Silicon Solar Array Project. Fifth quarterly report, March 21, 1977--May 27, 1977
The multiblade slurry technique capable of slicing 10 cm ingot into wafers 0.25 mm thick with only 0.20 mm kerf loss and 98% yield has been demonstrated. The total silicon requirement represents an ingot to sheet conversion of 0.95 m/sup 2//kg. Full production slicing tests have demonstrated the cost of MS slicing to contribute $40 to $50/m/sup 2/, with ''best effort'' estimates for today's configuration to be $30 to $35/m/sup 2/. By reducing material cost, and increasing the specific capacity of a saw to slice 900 wafers simultaneously, the long-term cost of MS slicing is estimated to be less than $10/m/sup 2/. The conversion of ingot to sheet is shown to be the most valuable contribution of slicing technology. At today's ingot costs, and with the thin wafer, low kerf loss slicing techniques demonstrated, the silicon material represents 5 to 10 times the cost of the wafering process in finished silicon wafers. Increasing the number of blades used in MS slicing from 100 to 150 to 225 to 300 has resulted in a reduction of yield to 33 to 70% for thin slicing, or an increase in wafer thickness to 0.30 mm slices. The limitation is intrinsic misalignment of multiple …
Date:
July 7, 1977
Creator:
Holden, S. C. & Fleming, J. R.
Object Type:
Report
System:
The UNT Digital Library
Clean Coal Technology III (CCT III) 10 MW demonstration of gas suspension absorption
The Gas Suspension Absorber (GSA) system brings coal combustion gases into contact with a suspended mixture of solids, including sulfur-absorbing lime. After the lime absorbs the sulfur pollutants, the solids are separated from the gases in a cyclone device and recirculated back into the system where they capture additional sulfur pollutant. The cleaned flue gases are sent through a dust collector before being released into the atmosphere. The key to the system's superior economic performance with high sulfur coals is the recirculation of solids. Typically, a solid particle will pass through the system about one hundred times before leaving the system. Another advantage of the GSA system is that a single spray nozzle is used to inject fresh lime slurry. The GSA system is expected to be the answer to the need of the US industry for an effective, economic and space efficient solution to the SO{sub 2} pollution problem.
Date:
February 7, 1992
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Geotoxic materials in the surface environment
The toxicology and natural occurrence of several recognized geotoxic elements including arsenic, cadmium, chromium, nickel, lead, selenium, uranium, and vanadium is reviewed. The behavior of these elements in the environment and in biological systems is examined. The properties of these eight toxic elements are summarized and presented in a toxicity matrix. The toxicity matrix identifies each of the elements in terms of average crustal abundance, average soil concentration, drinking water standards, irrigation water standards, daily human intake, aquatic toxicity, phytotoxicity, mammalian toxicity, human toxicity, and bioaccumulation factors for fish. Fish are the major aquatic environment contribution to the human diet and bioaccumulation in aquatic ecosystems has been demonstrated to be an important factor in the cycling of elements in aquatic ecosystems. The toxicity matrix is used as a first approximation to rank the geotoxicity of elements for the purpose of focusing future efforts. The ranking from highest to lowest toxicity with respect to the toxicity parameters being discussed is as follows: arsenic, cadmium, lead, selenium, chromium, vanadium, nickel, and uranium.
Date:
December 7, 1981
Creator:
Koranda, J.J.; Cohen, J.J.; Smith, C.F. & Ciminesi, F.J.
Object Type:
Report
System:
The UNT Digital Library
Testing of developmental neutral beam sources for MFTF
The design of a four-grid, spherically-focused, 10-by-46-cm area accelerator and ion source for the Mirror Fusion Test Facility (MFTF) has been previously described. This source was designed to operate at 80 kV-80 A for 0.5 s, and along with a matching, three-grid 20-kV-100-A-10-ms accelerator, has been built and tested. The 80-kV source has operated beyond design specifications to 90 kV-90 A for 12 ms. Pulse duration was limited by a capacitor bank accelerator power supply. Tests to 0.5 s on the High Voltage Test Stand (HVTS) are in progress. The major change found necessary during testing was the installation of a grounded shield to block neutralizer plasma from flowing into the region between high voltage and ground. The D/sub 1//sup +/:D/sub 2//sup +/:D/sub 3//sup +/ ratio was measured by Doppler shift spectroscopy and momentum analysis to be 0.68:0.20:0.12. Accelerator grids are built to a 7-m-radius spherical surface that aims individual beamlets at the center of curvature.
Date:
November 7, 1979
Creator:
Molvik, A.W.
Object Type:
Article
System:
The UNT Digital Library
Enhancing the use of coals by gas reburning-sorbent injection
Clean Coal Technology implies the use of coal in an environmentally acceptable manner. Coal combustion results in the emission of two types of acid rain precursors: oxides of sulfur (SO{sub x}) and oxides of nitrogen (NO{sub x}). This Clean Coal Technology project will demonstrate a combination of two developed technologies to reduce both NO{sub x} and SO{sub x} emissions: gas reburning and calcium based dry sorbent injection. The demonstrations will be conducted on two pre-NSPS utility boilers representative of the US boilers which contribute significantly to the inventory of acid rain precursor emissions: tangentially and cyclone fired units. Because of cost growth and lack of available funding, no further work has been done after Phase 1 at site B; the wall fired unit.
Date:
February 7, 1992
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Cloning and expression of the sulfoxide/sulfone/sulfonate/sulfate genes in Pseudomonads and Thiobacillae. [Pseudomonas, Thiobacillus, Rhodococcus]
The original conception of the work was that genetic determinants of the sulfoxide/sulfone/sulfonate/sulfate ( 4S'') pathway in Pseudomonas spp. would be cloned in vivo and then transferred to Thiobacillus spp. This ambition remains an appealing prospect; however, fulfilling that ambition has been confounded by an instability observed in the DbtS{sup +} phenotype in Pseudomonas spp. But the persisting interest in the phenotype has lead to isolation of fresh strains which have a DbtS{sup +} phenotype. One strain in particular, N1-36, has been the focus of extensive characterizations in long-term cultures. During the present quarter, seven cultures maintained in a fermentor'' for a week or longer have been run to determine rate and extent of growth, extent of conversion of dibenzothiophene (DBT) or dibenzosulfone (DBTO{sub 2}) to monohydroxybiphenyl (OH-BP), effect of pH maintained at 6.0, and the effect of adding glucose to cultures in which the amount of glucose had been diminished by bacterial consumption. In addition, a study of the effectiveness of using R68.445 as a vehicle for in vivo cloning of genes was completed this semester, and introduction of DbtS{sup +} determinants into Thiobacillus spp. continues to be an important goal.
Date:
February 7, 1992
Creator:
Krawiec, S.
Object Type:
Report
System:
The UNT Digital Library
New harmonic materials: index engineering. Thin-thick quadrature frequency conversion
The quadrature conversion scheme is a method of generating the second harmonic. The scheme, which uses two crystals in series, has several advantages over single-crystal or other two crystal schemes. The most important is that it is capable of high conversion efficiency over a large dynamic range of drive intensity and detuning angle. Consider a pair of KDP crystals cut for type-II phase matching. In the quadrature scheme, the optic axes of the crystals are arranged so that the plans containing the direction of the laser beam and their optic axes (the kz planes) are mutually perpendicular. This arrangement has two important properties. First, in type-II phase matching, the incident wave is polarized at 45 deg to the kz plane of the crystal. This, in the quadrature scheme, if the incident wave is correctly polarized for efficient conversion in the first crystal, it is also correctly polarized for efficient conversion in the second crystal. Both crystals can therefore convert efficiently.
Date:
February 7, 1985
Creator:
Eimerl, D.
Object Type:
Article
System:
The UNT Digital Library