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In-Situ Amelioration of Acid Mine Drainage Problems: Final Report
Final report
Date:
May 1998
Creator:
Brown, Terry H.
Object Type:
Report
System:
The UNT Digital Library
Modeling and sensitivity analysis study of the reduction of NO sub x by HNCO. [RAPRENOx process]
A chemical mechanism for the reduction of NO{sub x} by HNCO has been constructed to allow for the modeling of NO{sub x} in exhausts typical of natural gas combustion (RAPRENOx process). The reduction was modeled assuming plug flow, and either isothermal combustion or constant pressure adiabatic combustion. Variables were initial concentrations of NO, NO{sub 2}, CO, CH{sub 4}, H{sub 2}, and HNCO as well as initial temperatures. Exhaust residence time was nominally 1 s. Reduction was not achieved for prototypical natural gas exhaust'' for a reasonable residence time. Radical generation is crucial for reduction. H{sub 2} addition enhanced ignition and reduction. The final combustion temperature determines where NO{sub x} reduction ceases and NO{sub x} production increases. Reduction increases with HNCO, and breakthrough of NH{sub 3} and HNCO increses as well. N{sub 2}O production is due to NCO + NO, but the reduction of NO also occurs through reactions associated with the Thermal De-NOx chemistry. NH{sub 3} production and reactions are important to the reduction of NO. Sensitivity analysis under easy ignition conditions indicated that the same reactions involving nitrogen species, NH{sub 2} and NNH, important in De-NOx, are important when HNCO is used to reduce NO{sub x}. A real combustion …
Date:
May 1, 1992
Creator:
Brown, N. J. & Garay, J.
Object Type:
Report
System:
The UNT Digital Library
Dynamical evolution of cosmic strings
The author have studied by means of numerical simulations the dynamical evolution of a network of cosmic strings, both in the radiation and matter era. Our basic conclusion is that a scaling solution exists, i.e., the string energy density evolves as t/sup -2/. This means that the process by which long strings dump their energy into closed loops (which can gravitationally radiate away) is efficient enough to prevent the string domination over other forms of energy. This conclusion does not depend on the initial string energy density, nor on the various numerical parameters. On the other hand, the generated spectrum of loop sizes does depend on the value of our numerical lower cutoff (i.e., the minimum length of loop we allow to be chopped off the network). Furthermore, the network evolution is very different from what was assumed before), namely the creation of a few horizon sized loops per horizon volume and per hubble time, which subsequently fragment into about 10 smaller daughter loops. Rather, many tiny loops are directly cut from the network of infinite strings, and it appears that the only fundamental scale (the horizon) has been lost. This is probably because a fundamental ingredient had been overlooked, …
Date:
May 11, 1988
Creator:
Bouchet, F. R.
Object Type:
Article
System:
The UNT Digital Library
Inhibition of retrogressive reactions in coal/petroleum co-processing
The overall objective of this project is to develop a fundamental understanding of the reactions occurring at the onset of coke formation during the CO-processing of coals with action of chemical components, or groups of components, in coals and petroleum feedstocks to quantify and rank the effects of these components in retarding or enhancement of coke formation. The work involves bench scale reactions in microautoclaves, supplemented by studies of the carbonaceous residues by such techniques as diffuse reflectance Fourier transform infrared spectroscopy and {sup 13}C nuclear magnetic resonance spectrometry.
Date:
May 1, 1992
Creator:
Schobert, H. H. & Tomic, J.
Object Type:
Report
System:
The UNT Digital Library
Stability of trapped-particle modes in lower-hybrid pump
The stability of dissipative trapped-particle modes in the presence of a self-consistent lower-hybrid pump is analyzed theoretically. The pump can either be a single coherent wave or a spectrum of turbulent waves. Corresponding dispersion relations modified by the pump are derived and conditions for excitation and suppression of the modes are also discussed.
Date:
May 1, 1976
Creator:
Chen, L.; Kaw, P. K. & Tang, W. M.
Object Type:
Report
System:
The UNT Digital Library
Effect of deposits on corrosion of materials exposed in the Coal-Fired Flow Facility
Candidate heat exchanger materials tested in the Low Mass Flow train at the Coal-Fired Flow Facility (CFFF) at Tullahoma, TN. were analyzed to evaluate their corrosion performance. Tube specimens obtained at each foot of the 14-ft-long Unbend tubes were analyzed for corrosion-scale morphologies, scale thicknesses, and internal penetration depths. Results developed on 1500- and 2000- h exposed specimens were correlated with exposure temperature. In addition, deposit materials collected at several locations in the CFFF were analyzed in detail to characterize the chemical and physical properties of the deposits and their influence on corrosion performance of tube materials.
Date:
May 1, 1993
Creator:
Natesan, K.
Object Type:
Article
System:
The UNT Digital Library
Status report: A hydrologic framework for the Oak Ridge Reservation
This first status report on the Hydrologic Studies Task of the Oak Ridge Reservation Hydrology and Geology Study (ORRHAGS) revises earlier concepts of subsurface hydrology and hydrogeochemistry of the ORR. A new classification of hydrogeologic units is given, as well as new interpretations of the gydrogeologic properties and processes that influence contaminant migration. The conceptual hydrologic framework introduced in this report is based primarily on reinterpretations of data acquired during earlier hydrologic investigations of waste areas at and near the three US Department of Energy Oak Ridge (DOE-OR) plant facilities. In addition to describing and interpreting the properties and processes of the groundwater systems as they are presently understood, this report describes surface water-subsurface water relations, influences on contaminant migration,and implications to environmental restoration, environmental monitoring, and waste management.
Date:
May 1, 1992
Creator:
Solomon, D. K.; Toran, L. E.; Dreier, R. B.; Moore, G. K. & McMaster, W. M.
Object Type:
Report
System:
The UNT Digital Library
Some considerations in the splitting of interstitial frank loops formed by irradiation
The splitting of interstitial loops formed by irradiation is considered in detail. It is shown that they may split to form obtuse--angled single shear faults on the intersecting (111) planes. A detailed description of the splitting is given in which the interstitial Frank loop is viewed as being made up of perfect dislocation loop and two shears. The detailed description is then considered in the context of the formation of complex loops as are observed in quenching and irradiation studies. Experimentally observed geometries are explained viz, triangular loops within hexagonal ones etc. The nucleation of a DC' loop in complex interstitial loop formation is shown to be feasible. DC' has the magnitude of a perfect dislocation loop and encloses an intrinsic shear. (auth)
Date:
May 1, 1975
Creator:
Seshan, K.; Grilhe, J. & Washburn, J.
Object Type:
Article
System:
The UNT Digital Library
Atlantic Richfield Hanford Company quarterly report. Process technology and process development, January--March 1977
This quarterly report is the fourth in a series intended to provide information on research and engineering activities being performed to improve the processing of irradiated reactor fuels, the production of plutonium, and the management of resultant chemical wastes. The work reported here was performed during the period January through March 1977.
Date:
May 1, 1977
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Boronization in DIII-D
A thin boron film has been applied to the DIII-D tokamak plasma facing surfaces to reduce impurity influx, particularly oxygen and carbon. A direct result of this surface modification was the observation of a regime of very high energy confinement, VH-mode, with confinement times from 1.5 to 2 times greater than predicted by H-mode scaling relation for the same set of parameters. VH-mode discharges are characterized by low ohmic target densities, low edge neutral pressure, and reduced cycling. These conditions have reduced the collisionality, {nu}*, in the edge region producing a higher edge pressure gradient and a significant bootstrap current, up to 30% of the total current. We will describe the edge plasma properties after boronization including reductions in recycling inferred from measurements of {tau}{sup p}*. In particular we will discuss the edge plasma conditions necessary for access to VH-mode including the boronization process and properties of the deposited film.
Date:
May 1, 1992
Creator:
Jackson, G. L.; Burrell, K. H.; DeBoo, J. C.; Greenfield, C. M.; Groebner, R. J.; Hodapp, T. et al.
Object Type:
Article
System:
The UNT Digital Library
Catalytic fabric filtration for simultaneous NO sub x and particulate control
The objective of this program is to develop advanced concepts for removal of NO{sub x} from flue gas emitted by coalfired utility boilers, or for the control of NO{sub x} formation by advanced combustion modification techniques. Funded projects are required to focus on the development of technology that significantly advances the state of the art using a process or a combination of processes capable of reducing NO{sub x}. emissions to 60 ppM or less. The concept must have successfully undergone sufficient laboratory-scale development to justify scaleup for further evaluation at the pilot scale (not to exceed 5 MWe in size). Other requirements include production of a nonhazardous waste or a salable byproduct. The concept should have application to both new and retrofit coal-fired systems. The concept should also show the potential for a 50% cost savings when compared to a commercial selective catalytic reduction (SCR) process capable of meeting the 60-ppM NO{sub x} emission limit.
Date:
May 1, 1992
Creator:
Weber, G. F.; Ness, S. R.; Laudal, D. L. & Dunham, G.
Object Type:
Report
System:
The UNT Digital Library
SHIVA laser: nearing completion
Construction of the Shiva laser system is nearing completion. This laser will be operating in fall 1977 and will produce over 20 terawatts of focusable power in a subnanosecond pulse. Fusion experiments will begin early in 1978. It is anticipated that thermonuclear energy release equal to one percent that of the incident light energy will be achieved with sub-millimeter deuterium-tritium targets. From other experiments densities in excess of a thousand times that of liquid are also expected.
Date:
May 12, 1977
Creator:
Glaze, James A. & Godwin, Robert O.
Object Type:
Article
System:
The UNT Digital Library
Currents density measurements with an ion beam probe
It was shown that by the use of ion beam probing system with the proper detectors experimental expressions can be obtained for v/sub o/ = v/sub o/ (x,y,z) and v/sub d/ = v/sub d (x,y,z). It was also shown that by taking the curl of the difference between the equations, the magnetic field and consequently the plasma current density distribution can be evaluated.
Date:
May 1, 1975
Creator:
Connor, K. A.; Jennings, W. C. & Hickok, R. L.
Object Type:
Article
System:
The UNT Digital Library
Computer-based accountability system (Phase I) for special nuclear materials at Argonne-West
An automated accountability system for special nuclear materials (SNM) is under development at Argonne National Laboratory-West. Phase I of the development effort has established the following basic features of the system: a unique file organization allows rapid updating or retrieval of the status of various SNM, based on batch numbers, storage location, serial number, or other attributes. Access to the program is controlled by an interactive user interface that can be easily understood by operators who have had no prior background in electronic data processing. Extensive use of structured programming techniques make the software package easy to understand and to modify for specific applications. All routines are written in FORTRAN.
Date:
May 1, 1982
Creator:
Ingermanson, R. S. & Proctor, A. E.
Object Type:
Report
System:
The UNT Digital Library
Environmental status of the Lake Michigan region. Volume 3. Chemistry of Lake Michigan
The report is a synoptic review of data collected over the past twenty years on the chemistry of Lake Michigan. Changes in water quality and sediment chemistry, attributable to cultural and natural influences, are considered in relation to interacting processes and factors controlling the distribution and concentration of chemical substances within the Lake. Temperature, light, and mixing processes are among the important natural influences that affect nutrient cycling, dispersal of pollutants, and fate of materials entering the Lake. Characterization of inshore-offshore and longitudinal differences in chemical concentrations and sediment chemistry for the main body of the Lake is supplemented by discussion of specific areas such as Green Bay and Grand Traverse Bay. Residues, specific conductance, dissolved oxygen, major and trace nutrients, and contaminants are described in the following context: biological essentiality and/or toxicity, sources to the Lake, concentrations in the water column and sediments, chemical forms, seasonal variations and variation with depth. A summary of existing water quality standards, statutes, and criteria applicable to Lake Michigan is appended.
Date:
May 1, 1976
Creator:
Torrey, M S
Object Type:
Report
System:
The UNT Digital Library
Soft x-ray camera for internal shape and current density measurements on a noncircular tokamak
Soft x-ray measurements of the internal plasma flux surface shaped in principle allow a determination of the plasma current density distribution, and provide a necessary monitor of the degree of internal elongation of tokamak plasmas with a noncircular cross section. A two-dimensional, tangentially viewing, soft x-ray pinhole camera has been fabricated to provide internal shape measurements on the PBX-M tokamak. It consists of a scintillator at the focal plane of a foil-filtered pinhole camera, which is, in turn, fiber optically coupled to an intensified framing video camera (/DELTA/t />=/ 3 msec). Automated data acquisition is performed on a stand-alone image-processing system, and data archiving and retrieval takes place on an optical disk video recorder. The entire diagnostic is controlled via a PDP-11/73 microcomputer. The derivation of the polodial emission distribution from the measured image is done by fitting to model profiles. 10 refs., 4 figs.
Date:
May 1, 1988
Creator:
Fonck, R. J.; Jaehnig, K. P.; Powell, E. T.; Reusch, M.; Roney, P. & Simon, M. P.
Object Type:
Report
System:
The UNT Digital Library
Corrosion of several metals in supercritical steam at 538/sup 0/C. [85 alloys]
The corrosion of several iron- and nickel-base alloys in supercritical steam at 24.1 MPa (3500 psi) and 538/sup 0/C was measured to 7.92 x 10/sup 7/ s (22,000 h). The experiments were carried out in TVA's Bull Run Steam Plant. Corrosion was measured almost entirely by weight change and visual appearance; a few samples were evaluated by more descriptive analytical techniques. The corrosion rates of low-alloy ferritic steels containing from 1.1 to 8.7 percent Cr and 0.5 to 1.0 percent Mo differed by less than a factor of 2 in steam. Several modified compositions of Hastelloy N were evaluated and found to corrode at about equivalent rates. Of the alloys studied, the lowest weight gain in 3.6 x 10/sup 7/ sec (10,000 hr) was 0.01 mg/cm/sup 2/ for Inconel 718 and the highest 10 mg/cm/sup 2/ for the low-alloy ferritic steels. 25 figures, 3 tables.
Date:
May 1, 1977
Creator:
McCoy, H. E. & McNabb, B.
Object Type:
Report
System:
The UNT Digital Library
Piezo electric polaron and polaron pinning in n-CdS
The cyclotron resonance of the piezoelectric polaron in n-CdS has been investigated using far infrared spectroscopy at magnetic fields to 90 kOe. Both lamellar grating and Michelson Fourier transform spectrometers were used with a 0.3/sup 0/K Ge bolometer to study the photon energy region from 10 cm/sup -1/ to 60 cm/sup -1/. The theory of Miyake predicts that the frequency of the polaron's cyclotron resonance is shifted from the bare hand electron resonance frequency according to the expression: ..delta omega../sup p//sub c// ..cap omega../sub c/ varies as H/sup -1/ T/sup /sup 2///sup 3//. The magnetic field dependence of the present cyclotron resonance confirms this expression; the cyclotron mass isiezoelectric polaron effects. The bare band mass in n-CdS has also been determined by taking into account the Froehlich polaron interaction in addition to the piezoelectric polaron effects. For H parallel to the c-axis this cyclotron mass is 0.155 +- 0.005 m. The polaron pinning due to the 43 cm/sup -1/ optically inactive phonon has been observed.
Date:
May 1, 1976
Creator:
Nagasaka, K.
Object Type:
Report
System:
The UNT Digital Library
DT fusion neutron irradiation of two LLL superconductor wires at 4. 2/sup 0/K
The DT fusion neutron irradiation of two LLL superconductor wires at 4.2/sup 0/K is described. The sample position, beam-on time, and neutron dose record are given. The results from four ''profile'' dosimetry foils measuring the lateral variation in neutron flux are included.
Date:
May 18, 1977
Creator:
MacLean, S. C.
Object Type:
Report
System:
The UNT Digital Library
Correlation of radionuclide leachabilities with microstructures of glasses containing Savannah River Plant waste
Leachabilities of cesium and strontium from the glass matrices were correlated with the microstructures of glasses containing waste sludge from two SRP waste tanks. All sludge components, except mercury which volatilized, were completely soluble in the melt, but small amounts of crystalline iron oxide precipitated during cooling. These precipitates were less leachable than the glass matrix. Even though the compositions of the two sludges that were tested were similar, glass containing one of the sludges devitrified during heating at 600/sup 0/C; glass containing the other sludge did not devitrify. Leachability of the devitrified glass was as much as 100 times greater than that of nondevitrified glass, but still very low, less than 10/sup -6/ g/(cm/sup 2/)(day).
Date:
May 1, 1976
Creator:
Kelley, J. A. & Rankin, W. N.
Object Type:
Report
System:
The UNT Digital Library
International Nuclear Fuel Cycle Fact Book
As the US Department of Energy (DOE) and DOE contractors have become increasingly involved with other nations in nuclear fuel cycle and waste management cooperative activities, a need exists costs for a ready source of information concerning foreign fuel cycle programs, facilities, and personnel. This Fact Book has been compiled to meet that need. The information contained in the International Nuclear Fuel Cycle Fact Book has been obtained from many unclassified sources: nuclear trade journals and newsletters; reports of foreign visits and visitors; CEC, IAEA, and OECD/NMEA activities reports; and proceedings of conferences and workshops. The data listed typically do not reflect any single source but frequently represent a consolidation/combination of information.
Date:
May 1, 1992
Creator:
Leigh, I. W.
Object Type:
Report
System:
The UNT Digital Library
Alternatives for Managing Wastes From Reactors and Post-Fission Operations in the LWR Fuel Cycle: Volume 2. Alternatives for Waste Treatment
Volume II of the five-volume report is devoted to the description of alternatives for waste treatment. The discussion is presented under the following section titles: fuel reprocessing modifications; high-level liquid waste solidification; treatment and immobilization of chop-leach fuel bundle residues; treatment of noncombustible solid wastes; treatment of combustible wastes; treatment of non-high-level liquid wastes; recovery of transuranics from non-high-level wastes; immobilization of miscellaneous non-high-level wastes; volatile radioisotope recovery and off-gas treatment; immobilization of volatile radioisotopes; retired facilities (decontamination and decommissioning); and, modification and use of selected fuel reprocessing wastes. (JGB)
Date:
May 1, 1976
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Thorium utilization program progress report for January 1, 1974--June 30, 1975. [Reprocessing; refabrication; recycle fuel irradiations]
Work was carried out on the following: HTGR reprocessing development and pilot plant, refabrication development and pilot plant, recycle fuel irradiations, engineering and economic studies, and conceptual design of a commercial recycle plant. (DLC)
Date:
May 1, 1976
Creator:
Lotts, A. L. & Kasten, P. R.
Object Type:
Report
System:
The UNT Digital Library
Segregation induced embrittlement of grain interfaces
Conditions are discussed under which an interface, possibly containing an adsorbed species, is capable of sustaining an atomistically sharp cleavage crack, rather than having any such crack blunt out via dislocation nucleation. Two models for ductile versus brittle interface response are discussed. One of these is applied to model grain boundaries in face centered cubic materials, and is used to compare predictions with experimental observations on the embrittlement of Cu polycrystals by the addition of dilute concentrations of Bi. The general results are in qualitative agreement, although the model predicts behavior that is, in general, more ductile than that observed experimentally. Several possible reasons for this excess ductility are discussed. An appendix presents an analysis of the work of reversible separation of an interface containing a segregated species. This is intended to clarify some issues recently raised in the literature on interfacial embrittlement, especially concerning the distinctions that must be drawn between expressions for cohesive energy reductions for interfacial separation at constant chemical potential, ..mu.., versus separation with constant concentration, GAMMA, of the adsorbate species.
Date:
May 1, 1977
Creator:
Mason, D D
Object Type:
Report
System:
The UNT Digital Library