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Retrospective examination of geothermal environmental assessments (open access)

Retrospective examination of geothermal environmental assessments

Since 1976, the Department of Energy (DOE) has supported a variety of programs and projects dealing with the exploration, development, and utilization of geothermal energy. This report presents an overview of the environmental impacts associated with these efforts. Impacts that were predicted in the environmental analyses prepared for the programs and projects are reviewed and summarized, along with measures that were recommended to mitigate these impacts. Also, for those projects that have gone forward, actual impacts and implemented mitigation measures are reported, based on telephone interviews with DOE and project personnel. An accident involving spills of geothermal fluids was the major environmental concern associated with geothermal development. Other important considerations included noise from drilling and production, emissions of H/sub 2/S and cooling tower drift, disposal of solid waste (e.g., from H/sub 2/S control), and the cumulative effects of geothermal development on land use and ecosystems. Mitigation measures were frequently recommended and implemented in conjunction with noise reduction; drift elimination; reduction of fugitive dust, erosion, and sedimentation; blowout prevention; and retention of wastes and spills. Monitoring to resolve uncertainties was often implemented to detect induced seismicity and subsidence, noise, drift deposition, concentrations of air and water pollutants, and effects on groundwater. …
Date: March 1, 1984
Creator: Webb, J. W.; Eddlemon, G. K. & Reed, A. W.
System: The UNT Digital Library
Electronic band structure and optical properties of the cubic, Sc, Y and La hydride systems (open access)

Electronic band structure and optical properties of the cubic, Sc, Y and La hydride systems

Electronic band structure calculations are used to interpret the optical spectra of the cubic Sc, Y and La hydride systems. Self-consistent band calculations of ScH/sub 2/ and YH/sub 2/ were carried out. The respective joint densities of states are computed and compared to the dielectric functions determined from the optical measurements. Additional calculations were performed in which the Fermi level or band gap energies are rigidly shifted by a small energy increment. These calculations are then used to simulate the derivative structure in thermomodulation spectra and relate the origin of experimental interband features to the calculated energy bands. While good systematic agreement is obtained for several spectral features, the origin of low-energy interband transitions in YH/sub 2/ cannot be explained by these calculated bands. A lattice-size-dependent premature occupation of octahedral sites by hydrogen atoms in the fcc metal lattice is suggested to account for this discrepancy. Various non-self-consistent calculations are used to examine the effect of such a premature occupation. Measurements of the optical absorptivity of LaH/sub x/ with 1.6 < x < 2.9 are presented which, as expected, indicate a more premature occupation of the octahedral sites in the larger LaH/sub 2/ lattice. These experimental results also suggest that, …
Date: January 1, 1980
Creator: Peterman, D. J.
System: The UNT Digital Library
Safety rod latch inspection (open access)

Safety rod latch inspection

During an attempt to raise control rods from the 100 K reactor in December, one rod could not be withdrawn. Subsequent investigation revealed that a small button'' in the latch mechanism had broken off of the lock plunger'' and was wedged in a position that prevented rod withdrawal. Concern that this failure may have resulted from corrosion or some other metallurgical problem resulted in a request that SRL examine six typical latch mechanisms from the 100 L reactor by use of radiography and metallography. During the examination of the L-Area latches, a failed latch mechanism from the 100 K reactor was added to the investigation. Fourteen latches that had a history of problems were removed from K-Area and sent to SRL for inclusion in this study the week after the original seven assemblies were examined, bringing the total of latch assemblies discussed in this report to twenty one. Results of the examination of the K-Area latch that initiated this study is not included in this report.
Date: February 1, 1992
Creator: Leader, D.R.
System: The UNT Digital Library
Redox reactions involving chromium, plutonium, and manganese in soils (open access)

Redox reactions involving chromium, plutonium, and manganese in soils

Plutonium speciation in soils is discussed. Chromium was selected as a model for studying soil Pu. Similarities between Cr and Pu are pointed out, and a hypotheses concerning Pu speciation in soils is presented. Findings from Cr oxidation studies that may be relevant to the problem of Pu oxidation in soils are discussed. (JGB)
Date: January 1, 1979
Creator: Amacher, M.C. & Baker, D.E.
System: The UNT Digital Library
An update on passive correctors for the SSC dipole magnets (open access)

An update on passive correctors for the SSC dipole magnets

The concept of correction of the magnetization sextupole became a topic of discussion as soon as it was realized that superconductor magnetization could have a serious effect on the SSC beam during injection. Several methods of correction were proposed. These included (1) correction with active bore tube windings like those on the HERA machine which correct out magnetization sextupole and the sextupole due to iron saturation, (2) correction with persistent sextupole windings mounted on the bore tube (3) correction using passive superconductor (4) correction using ferromagnetic material, and (5) correction using oriented magnetized materials. This report deals with the use of passive superconductor to correct the magnetization sextupole. Two basic methods are explored in this report: (1) One can correct the magnetization sextupole by changing the diameter of the superconductor filaments in one or more blocks of the SSC dipole. (2) One can correct the magnetization sextupole and decapole by mounting passive superconducting wires on the inside of the SSC dipole coil bore. In addition, an assessment of the contribution of each conductor in the dipole to the magnetization sextupole and decapole is shown. 38 refs, 25 figs., 15 tabs.
Date: May 1, 1991
Creator: Green, Michael A.
System: The UNT Digital Library
Supporting Analysis for Thermal Suitability of Fuel Elements for SM-1A Core I Loading (open access)

Supporting Analysis for Thermal Suitability of Fuel Elements for SM-1A Core I Loading

A recommended SM-1A Core I loading chart was derived from available, metallurgically acceptable elements at the SM-1A and SM-1 sites. The derivation was based on local thermal and hydraulic considerations of minimum elementto- element coolant channel clearances. These clearances were determined from field inspection measurements of outer fuel plate spacing, as modified by analytical calculations of plate ripple growth during exposure to reactor operating thermal stresses. (auth)
Date: January 10, 1962
Creator: Brondel, J. O.
System: The UNT Digital Library
Chemical Technology Division, Unit Operations Section Monthly Progress Report, June 1961 (open access)

Chemical Technology Division, Unit Operations Section Monthly Progress Report, June 1961

An interfacial viseometer was built for use in an interfacial phenomena study. Installation of a 6-in.-ID foam separation column system was completed. The dispersiondrying-sintering characteristics of six low-nitrate batches of thoria sol material were studied. The average effective porosity of the CuO pellets used for reactor helium purification was determined to be 0.0545 for H/ sub 2/ transport and 0.0526 for CO transport. In continuous Zirflex dissolution studies, no H/sub 2/O/sub 2/ decomposition was observed when 10% H/sub 2/O/sup 2 was fed into boiling dissoivent through a water-cooled nozzle and the oxygen concentration in the scrubbed off-gas could be used to control the H/sub 2/O/sub 2/ concentration in the dissolver. The free fluoride in Zirflex solutions must be maintained above 1 molar in order to prevent uranium precipitation at low concentrations of uranium even though the F/sup -//U ratio exceeds 100. Chopped stainless steel-clad UO/sub 2/ sections were leached in a 4 stage pyrex leacher model using 6, 7, and 8 M nitric acid as the dissolvent. The temperature distribution expected within fuel elements consisting of square arrays of tubes was calculated for shipping conditions assuming heat to be transferred only by radiation. HETS values were calculated for uranium stripping …
Date: January 23, 1962
Creator: Whatley, M. E.; Haas, P. A.; Horton, R. W.; Ryon, A. D.; Suddath, J. C. & Watson, C. D.
System: The UNT Digital Library
Vacuum ultraviolet electronic properties of liquids. Annual progress report, 1 November 1979-31 October 1980 (open access)

Vacuum ultraviolet electronic properties of liquids. Annual progress report, 1 November 1979-31 October 1980

Areas covered are: optical and dielectric properties of hexamethyl-phosphoric triamide; photoemission from uv irradiated liquids; photon and photoelectron mean free paths in liquids; properties of Kapton films; and uv transmission of polycyclic organic molecules. (GHT)
Date: January 1, 1980
Creator: Painter, L.R.
System: The UNT Digital Library
Geothermal Materials Development, Annual Report FY 1991 (open access)

Geothermal Materials Development, Annual Report FY 1991

Advances in the development of new materials, the commercial availabilities of which are essential for the attainment of Hydrothermal Category Level I and II Objectives, continue to be made in the Geothermal Materials Development Project. Many successes have already been accrued and the results used commercially. In FY 1991, utility company sponsored full cost'' recovery programs based upon materials technology developed in this project were initiated on topics such as condensing heat exchangers, high temperature composites for utility vaults used in district heating systems, and corrosion resistant coatings for use in oil-fired electric generating processes. In FY 1991 the DOE/GD-sponsored R D project was focused on reducing well drilling, fluid transport and energy conversion costs. Specific activities being performed included lightweight CO{sub 2}- resistant well cements, chemical systems for lost circulation control, thermally conductive and scale resistant protective linear systems, corrosion mitigation in process components at The Geysers, and elastomer-metal bonding systems needed for use in high temperature well drilling and safety related applications.
Date: December 1, 1991
Creator: Kukacka, L. E.
System: The UNT Digital Library
Development of 400- to 450-MHz RFQ resonator-cavity mechanical designs (open access)

Development of 400- to 450-MHz RFQ resonator-cavity mechanical designs

In the development of the radio-frequency quadrupole (RFQ) linac, the resonator cavity's mechanical design may be a challenge similar in magnitude to that of the development of the accelerator structure itself. Experience with the all-copper 425-MHz RFQ proof-of-principle linac has demonstrated that the resonator cavity must be structurally stiff and easily tunable. This experience has led to development of copper-plated steel structures having vanes that may be moved within a cylinder for tuning. Design of a flexible vane-to-cylinder radio-frequency (rf) joint, the vane, and the cylinder has many constraints dictated by the small-diameter cavities in the 400-MHz-frequency region. Two types of flexible, mechanical vane-to-cylinder rf joints are being developed at Los Alamos: the C-seal and the rf clamp-joint.
Date: January 1, 1982
Creator: Hansborough, L.D.
System: The UNT Digital Library
Video monitoring system for enriched uranium casting furnaces (open access)

Video monitoring system for enriched uranium casting furnaces

A closed-circuit television (CCTV) system was developed to upgrade the remote-viewing capability on two oralloy (highly enriched uranium) casting furnaces in the Y-12 Plant. A silicon vidicon CCTV camera with a remotely controlled lens and infrared filtering was provided to yield a good-quality video presentation of the furnace crucible as the oralloy material is heated from 25 to 1300/sup 0/C. Existing tube-type CCTV monochrome monitors were replaced with solid-state monitors to increase the system reliability.
Date: March 1, 1978
Creator: Turner, P. C.
System: The UNT Digital Library
STAINLESS STEEL WASTES. III. LABORATORY STUDIES OF THE RATE OF REMOVAL OF STAINLESS STEEL IONS BY MERCURY CATHODE ELECTROLYSIS (open access)

STAINLESS STEEL WASTES. III. LABORATORY STUDIES OF THE RATE OF REMOVAL OF STAINLESS STEEL IONS BY MERCURY CATHODE ELECTROLYSIS

ABS> The removal rates of iron, nickel, and chromium from synthetic stainless steel waste solutions during electrolysis over a mercury cathode were studied. The loading capacity of the mercury for the stainless steel metals was estimated on the basis of laboratory experiments to be about two% by weight. The laboratory data indicated that, at an electrode potential of --1.80 voits vs S.C.E., 85 ampere-hours per liter of waste removed essentially all of the stainless steel ions from a sulfuric acid solution containing 0.13M metal ions at 35 deg C. (auth)
Date: February 12, 1962
Creator: Anderson, D. R. & Rhodes, D. W.
System: The UNT Digital Library
BRAZING OF CERAMICS. Progress Report (open access)

BRAZING OF CERAMICS. Progress Report

Brazing alloys such as 48 Ti-48 Zr-4 Be (wt%) and 49 Ti-49 Cu-2 Be (wt%) have been found to readily flow on oxide and graphite ceramics. Two demonstrati on fuel element assemblies were fabricated to illustrate the usefulness of these procedures for nuclear applications. One of these assemblies contained graphite tubes and end caps which were brazed to a molybdenum hanger. The second demonstration fuel element was composed of a compartmented aluminum oxide plate to which aluminum oxide cover plates were brazed. (R.J.S.)
Date: November 1, 1962
Creator: Fox, C.W.
System: The UNT Digital Library
Stress corrosion cracking of uranium--niobium alloys (open access)

Stress corrosion cracking of uranium--niobium alloys

The stress corrosion cracking behavior of U-2/sup 1///sub 4/, 4/sup 1///sub 2/, 6 and 8 wt % Nb alloys was evaluated in laboratory air and in aqueous Cl/sup -/ solutions. Thresholds for crack propagation were obtained in these environments. The data showed that Cl/sup -/ solutions are more deleterious than air environments. Tests were also conducted in pure gases to identify the species in the air responsible for cracking. These data showed the primary stress corrodent is water vapor for the most reactive alloy, U-2/sup 1///sub 4/% Nb, while O/sub 2/ is primarily responsible for cracking in the more corrosion resistant alloys, U-6 and 8% Nb. The 4/sup 1///sub 2/% alloy was found to be susceptible in both H/sub 2/O and O/sub 2/ environments.
Date: March 1, 1978
Creator: Magnani, N.J.
System: The UNT Digital Library
Murakami density limit in tokamaks and reversed-field pinches (open access)

Murakami density limit in tokamaks and reversed-field pinches

A theoretical upper limit for the density in an ohmically heated tokamak discharge follows from the requirement that the ohmic heating power deposited in the central current-carrying channel exceed the impurity radiative cooling in this critical region. A compact summary of our results gives this limit n/sub M/ for the central density as n/sub M/ = (Z/sub e//(Z/sub e/-1)/sup 1/2/n/sub eo/ (B/sub T//1T)(1m/R) where n/sub eo/ depends strongly on the impurity species and is remarkably independent of the central electron temperature T/sub e/(0). For T/sub e/(0) approx. 1 keV, we have n/sub eo/ = 1.5 x 10/sup 14/ cm/sup -3/ for beryllium, n/sub eo/ = 5 x 10/sup 13/ cm/sup -3/ for oxygen, n/sub eo/ = 1.0 x 10/sup 13/ cm/sup -3/ for iron, and n/sub eo/ = 0.5 x 10/sup 13/ cm/sup -3/ for tungsten. The results agree quantitatively with Murakami's original observations. A similar density limit, known as the I/N limit, exists for reversed-field pinch devices and this limit has also been evaluated for a variety of impurity species.
Date: March 1, 1984
Creator: Perkins, F.W. & Hulse, R.A.
System: The UNT Digital Library
Selected constituents in the smoke of domestic low tar cigarettes (open access)

Selected constituents in the smoke of domestic low tar cigarettes

Thirty-two brands of domestic commercial low tar and nicotine cigarettes were analyzed for their production of tar, nicotine, nitrogen oxides (as nitric oxide), hydrogen cyanide, acrolein, carbon monoxide and carbon dioxide under standard analytical smoking conditions. Results are compared with published data for certain brands.
Date: December 1, 1977
Creator: Griest, W. H.; Quincy, R. B. & Guerin, M. R.
System: The UNT Digital Library
Sonic enhanced ash agglomeration and sulfur capture (open access)

Sonic enhanced ash agglomeration and sulfur capture

The major objective of the Phase 1 test program is to confirm the feasibility of the Manufacturing and Technology Conversion International, Inc. bimodal particle size approach to enhance particulate control by acoustic ash agglomeration. An ancillary objective of the Phase 1 effort is to demonstrate and confirm the feasibility of an acoustic field to enhance sulfur capture by increasing sorbent reactivity. Phase 1 tests are designed to cover the frequency range between 50 and 1400 Hz, establish monomodal baseline performance as a benchmark from which to measure the degree of enhancement expected from the bimodal approach, and, finally, to confirm the effectiveness of low-frequency fields over high-frequency fields for realistic particulate streams. The program will demonstrate the effectiveness of a unique approach which uses a bimodal distribution composed of large sorbent particles and fine fly ash particles to enhance ash agglomeration and sulfur capture at conditions found in direct coal-fired turbines. Under the impact of high-intensity sound waves, sorbent reactivity and utilization, it is theorized, will increase while agglomerates of fly ash and sorbents are formed which are readily collected in commercial cyclones. The work will extend the concept from the demonstration of feasibility (Phase 1), through proof-of-concept (Phase 2) …
Date: January 1, 1991
Creator: unknown
System: The UNT Digital Library
Accidental Radiogold (198Au) Liver Scan Overdose With Fatal Outcome (open access)

Accidental Radiogold (198Au) Liver Scan Overdose With Fatal Outcome

This report addresses the use of radioisotopes for scanning, which has added significantly to the clinician's ability to detect and interpret disease manifestations.
Date: October 31, 1969
Creator: Baron, J.M.; Yachnin, S.; Polcyn, R.; Fitch, F.W. & Sturner, W.G.
System: The UNT Digital Library
MULTI-NODE SIMULATION OF THE FFTF INTERMEDIATE HEAT EXCHANGER. (open access)

MULTI-NODE SIMULATION OF THE FFTF INTERMEDIATE HEAT EXCHANGER.

None
Date: January 1, 1966
Creator: Gerhardstein, L.H.
System: The UNT Digital Library
Sol-Gel Processes for Isotopic Heat Sources. (open access)

Sol-Gel Processes for Isotopic Heat Sources.

None
Date: October 31, 1969
Creator: unknown
System: The UNT Digital Library
The Effects of Irradiation on Some Binary Alloys of Thorium-Plutonium and Zirconium-Plutonium (open access)

The Effects of Irradiation on Some Binary Alloys of Thorium-Plutonium and Zirconium-Plutonium

A specimen of cast thorium-5 wt% plutonium and one of thorium-10 wt% plutonium were irradiated to total atom burnups of 1.9 and 2.6%, respectively, at maximum fuel temperatures of approximately 450 deg C. Both alloys displayed excellent dimensional stability with volume increases of 0.8 and 1.2% per atom per cent burnup, respectively. Three cold-rolled specimens of zirconium-5 wt% plutonium and one cold-rolled specimen of zirconium-7 wt% plutonium were also irradiated. The zirconium- plutonium alloy specimens all showed extremely poor dimensional stability, with anisotropic elongations ranging from approximately 100 to 500%. The irradiation growth coefficients for these specimens ranged from 90 to 210 microinches per inch per atom per cent burnup. The poor dimensional stability of the zirconium-- plutonium alloy specimens is attributed to a highly preferred grain orientation that presumably developed during cold rolling. (auth)
Date: July 1, 1962
Creator: Horak, J. A.; Kittel, J. H. & Rhude, H. V.
System: The UNT Digital Library
OPERATIONAL ACCIDENTS AND RADIATION EXPOSURE EXPERIENCE WITHIN THE UNITED STATES ATOMIC ENERGY COMMISSION, 1943--1967. (open access)
Recording Equipment for Internal Friction Measurements (open access)

Recording Equipment for Internal Friction Measurements

An apparatus was developed for recording internal friction data in such a manner as to circumvent many of the laborious and time-consuming observations and calculations usually associated with these measurements. An optical lever is used and the passage of the beam across the scale is detected by photoconductive cells. The cells are strategically located so that, when their signals are fed through a multichannel switching circuit to the pens of an operation recorder, a plot of the logarithm of the vibrational amplitude versus the number of cycles is recorded on the chart. From the definitmon of the logarithmic decrement, ( delta ), it can be shown that the slope of this curve is - delta . The apparatus is inexpensive and requires a minimum of maintenance. It has been used for accurate determinations of values of delta from below 0.0001 up to 0.3. (auth)
Date: October 31, 1961
Creator: Stephenson, R. L. & McCoy, H. E. Jr.
System: The UNT Digital Library
PROGRESS REPORT ON [ESR STUDIES ON TRAPPED SPECIES IN IRRADIATED SOLIDS]. (open access)

PROGRESS REPORT ON [ESR STUDIES ON TRAPPED SPECIES IN IRRADIATED SOLIDS].

None
Date: January 1, 1969
Creator: Hamlet, P.L.
System: The UNT Digital Library