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Aerial thermography studies of power plant heated lakes
Remote sensing temperature measurements of water bodies is complicated by the temperature differences between the true surface or skin water and the bulk water below. Weather conditions control the reduction of the skin temperature relative to the bulk water temperature. Typical skin temperature depressions range from a few tenths of a degree Celsius to more than one degree. In this research project, the Savannah River Technology Center (SRTC) used aerial thermography and surface-based meteorological and water temperature measurements to study a power plant cooling lake in South Carolina. Skin and bulk water temperatures were measured simultaneously for imagery calibration and to produce a database for modeling of skin temperature depressions as a function of weather and bulk water temperatures. This paper will present imagery that illustrates how the skin temperature depression was affected by different conditions in several locations on the lake and will present skin temperature modeling results.
Date:
January 26, 2000
Creator:
Villa-Aleman, E.
Object Type:
Article
System:
The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 100, No. 266, Ed. 1 Wednesday, January 26, 2000
Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date:
January 26, 2000
Creator:
Bush, Michael
Object Type:
Newspaper
System:
The Gateway to Oklahoma History
The Alvin Advertiser (Alvin, Tex.), Ed. 1 Wednesday, January 26, 2000
Weekly newspaper from Alvin, Texas that includes local, state, and national news along with advertising.
Date:
January 26, 2000
Creator:
unknown
Object Type:
Newspaper
System:
The Portal to Texas History
The B {r{underscore}arrow} D*{ell}{nu} form factor at zero recoil
The authors describe a model independent lattice QCD method for determining the deviation from unity for h{sub A{sub 1}}, the B {r{underscore}arrow} D*{ell}{nu} form factor at zero recoil. They extend the double ratio method previously used to determine the B {r{underscore}arrow} D{ell}{nu} form factor. The bulk of statistical and systematic errors cancel in the double ratios they consider, yielding form factors which promise to reduce present theoretical uncertainties in the determination of {vert{underscore}bar}V{sub cb}{vert{underscore}bar}. They present results from a prototype calculation at a single lattice spacing corresponding to {beta} = 5.7.
Date:
January 26, 2000
Creator:
Simone, J. N.; Hashimoto, S.; El-Khadra, A. X.; Kronfeld, A. S.; Mackenzie, P. B. & Ryan, S. M.
Object Type:
Article
System:
The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 78, No. 75, Ed. 1 Wednesday, January 26, 2000
Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date:
January 26, 2000
Creator:
Cash, Wanda Garner
Object Type:
Newspaper
System:
The Portal to Texas History
C-106 High-Level Waste Solids: Washing/Leaching and Solubility Versus Temperature Studies
This report describes the results of a test conducted by Battelle to assess the effects of inhibited water washing and caustic leaching on the composition of the Hanford tank C-106 high-level waste (HLW) solids. The objective of this work was to determine the composition of the C-106 solids remaining after washing with 0.01M NaOH or leaching with 3M NaOH. Another objective of this test was to determine the solubility of various C-106 components as a function of temperature. The work was conducted according to test plan BNFL-TP-29953-8,Rev. 0, Determination of the Solubility of HLW Sludge Solids. The test went according to plan, with only minor deviations from the test plan. The deviations from the test plan are discussed in the experimental section.
Date:
January 26, 2000
Creator:
Lumetta, G. J.; Bates, D. J.; Berry, P. K.; Bramson, J. P.; Darnell, L. P.; Farmer, O. T., III et al.
Object Type:
Report
System:
The UNT Digital Library
Characterization of and waste acceptance radionuclide to be reported for the 2nd macro-batch of high-level waste sludge being vitrified in the DWPF melter
The Defense Waste Processing Facility (DWPF), at the Savannah River Site (SRS), is currently processing the second million gallon batch (Macro-Batch 2) of radioactive sludge slurry into a durable borosilicate glass for permanent geological disposal. To meet the reporting requirements as specified in the Department of Energy's Waste Acceptance Product Specifications (WAPS), for the final glass product, the nonradioactive and radioactive compositions must be provided for a Macro-Batch of material. In order to meet this requirement, sludge slurry samples from Macro-Batch 2 were analyzed in the Shielded Cells Facility of the Savannah River Technology Center (SRTC). This information is used to complete the necessary Production Records at DWPF so that the final glass product, resulting from Macro Batch 2, may be disposed of at a Federal Repository. This paper describes the results obtained from the analyses of the sludge slurry samples taken from Macro-Batch 2 to meet the reporting requirements of the WAPS. Twenty eight elements were identified for the nonradioactive composition and thirty one for the radioactive composition. The reportable radioisotopes range from C-14 to Cm-246.
Date:
January 26, 2000
Creator:
Fellinger, T. L.
Object Type:
Article
System:
The UNT Digital Library
Characterization of melt-infiltrated SiC/SiC composite combustor liners using meso- and micro-NDE techniques
Melt-infiltrated ceramic matrix composite SiC/SiC material systems are under development for use in combustor liners for low-emission advanced gas turbines. Uncertainty in repeatability of processing methods for these large components (33--76 cm diameter), and hence possible reduced reliability for the end user. This requires that appropriate test methods, at both meso- and micro-scale, be used to ensure that the liners are acceptable for use. Nondestructive evaluation (NDE) methods, if demonstrated to reliably detect changes caused by processing, would be of significant benefit to both manufacturer and end user. This paper describes the NDE methods and their applications in detecting a process upset in a melt-infiltrated 33 cm combustor liner and how high-resolution scanning electron microscopy was used to verify the NDE data.
Date:
January 26, 2000
Creator:
Ellingson, W. A.; Sun, J. G.; More, K. L. & Hines, R.
Object Type:
Article
System:
The UNT Digital Library
Chemical Vapor Deposition of Fluoroalkylsilane Monolayer Films for Adhesion Control in Microelectromechanical Systems
We have developed a new process for applying a hydrophobic, low adhesion energy coating to microelectromechanical (MEMS) devices. Monolayer films are synthesized from tridecafluoro-1,1,2,2-tetrahydrooctyltrichlorosilane (FOTS) and water vapor in a low-pressure chemical vapor deposition process at room temperature. Film thickness is self-limiting by virtue of the inability of precursors to stick to the fluorocarbon surface of the film once it has formed. We have measured film densities of {approx}3 molecules nm{sup 2} and film thickness of {approx}1 nm. Films are hydrophobic, with a water contact angle >110{sup o}. We have also incorporated an in-situ downstream microwave plasma cleaning process, which provides a clean, reproducible oxide surface prior to film deposition. Adhesion tests on coated and uncoated MEMS test structures demonstrate superior performance of the FOTS coatings. Cleaned, uncoated cantilever beam structures exhibit high adhesion energies in a high humidity environment. An adhesion energy of 100 mJ m{sup -2} is observed after exposure to >90% relative humidity. Fluoroalkylsilane coated beams exhibit negligible adhesion at low humidity and {<=} 20 {micro}J m{sup -2} adhesion energy at >90% relative humidity. No obvious film degradation was observed for films exposed to >90% relative humidity at room temperature for >24 hr.
Date:
January 26, 2000
Creator:
MAYER,THOMAS M.; DE BOER,MAARTEN P.; SHINN,NEAL D.; CLEWS,PEGGY J. & MICHALSKE,TERRY A.
Object Type:
Article
System:
The UNT Digital Library
The Clifton Record (Clifton, Tex.), Vol. 105, No. 7, Ed. 1 Wednesday, January 26, 2000
Semi-weekly newspaper from Clifton, Texas that includes local, state, and national news along with advertising.
Date:
January 26, 2000
Creator:
Smith, W. Leon
Object Type:
Newspaper
System:
The Portal to Texas History
The Collegian (Hurst, Tex.), Vol. 12, No. 16, Ed. 1 Wednesday, January 26, 2000
Weekly student newspaper published in Hurst, Texas and serving the Tarrant County College District that includes school news and information along with advertising.
Date:
January 26, 2000
Creator:
unknown
Object Type:
Newspaper
System:
The Portal to Texas History
Copper studies for alternative salt disposition
The purpose of this study is to determine, as functions of total copper loading and iron REDOX in glass, any dependence of the leaching behavior of borosilicate glass on metallic copper.
Date:
January 26, 2000
Creator:
Brown, K.G.
Object Type:
Report
System:
The UNT Digital Library
Correction of high gradient quadrupole harmonics with magnetic shims
Superconducting quadrupole magnets with 70 mm aperture and nominal field gradient of 215 T/m are being developed by the US-LHC Accelerator Project for the Interaction Regions of the Large Hadron Collider. Due to large beam size and orbit displacement in the final focusing triplet, these magnets are subject to stringent field quality requirements. For this reason, a correction scheme based on magnetic shims was investigated. This paper reports design calculations, fabrication issues and tests results involving magnetic shims.
Date:
January 26, 2000
Creator:
Sabbi, G.
Object Type:
Article
System:
The UNT Digital Library
Coupling Automated Electron Backscatter Diffraction with Transmission Electron and Atomic Force Microscopies
Grain boundary network engineering is an emerging field that encompasses the concept that modifications to conventional thermomechanical processing can result in improved properties through the disruption of the random grain boundary network. Various researchers have reported a correlation between the grain boundary character distribution (defined as the fractions of special and random grain boundaries) and dramatic improvements in properties such as corrosion and stress corrosion cracking, creep, etc. While much early work in the field emphasized property improvements, the opportunity now exists to elucidate the underlying materials science of grain boundary network engineering. Recent investigations at LLNL have coupled automated electron backscatter diffraction (EBSD) with transmission electron microscopy (TEM) and atomic force microscopy (AFM) to elucidate these fundamental mechanisms. This investigation provides evidence that grain boundary network engineering and the formation of annealing twins disrupt the connectivity of the random grain boundary network and is likely responsible for the experimentally observed improvement in properties. This work illustrates that coupling of automated EBSD with other microstructural probes such as TEM and AFM provides data of greater value than any single technique in isolation. The coupled techniques have been applied to aid in understanding the underlying mechanisms of grain boundary network engineering …
Date:
January 26, 2000
Creator:
Schwartz, A.J.; Kumar, M.; Bedrossian, P.J. & King, W.E.
Object Type:
Article
System:
The UNT Digital Library
Defense Inventory: Opportunities Exist to Expand the Use of Defense Logistics Agency Best Practices
A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a legislative requirement, GAO evaluated the extent to which the Defense Logistics Agency (DLA) has implemented commercial inventory practice initiatives contained in a schedule submitted to Congress, focusing on: (1) DLA's progress in implementing the initiatives; and (2) opportunities to build on and expand existing efforts."
Date:
January 26, 2000
Creator:
United States. General Accounting Office.
Object Type:
Report
System:
The UNT Digital Library
Desorption Kinetics of H2O from Cab-O-Sil-M-7D and Hi-Sil-233 Silica Particles
Temperature programmed desorption (TPD) was performed at temperatures up to 850K on Cab-O-Sil-M-7D and Hi-Sil-233 silica particles. Physisorbed water molecules on both types of silica had activation energies in the range of 9-14.5 kcal/mol. However, the activation energies of desorption for chemisorbed water varied from {approx} 19 kcal/mol to > 59 kcal/mol for Cab-O-Sil-M-7D, and {approx} 23-37 kcal/mol for Hi-Sil-233. Our results suggest that physisorbed water can be effectively pumped away at room temperature (or preferably at 320 K) in a matter of hours. Chemisorbed water with high activation energies of desorption (>30 kcal/mol) will not escape the silica surfaces in 100 years even at 320 K, while a significant amount of the chemisorbed water with medium activation energies (19-26 kcal/mol) will leave the silica surfaces in that time span. Most of the chemisorbed water with activation energies < 30 kcal/mol can be pumped away in a matter of days in a good vacuum environment at 500 K. We had previously measured about 0.1-0.4 wt. % of water in M9787 polysiloxane formulations containing {approx} 21% Cab-O-Sil-M-7D and {approx} 4% Hi-Sil-233. Comparing present results with these formulations, we conclude that absorbed H{sub 2}O and Si-OH bonds on the silica surfaces are …
Date:
January 26, 2000
Creator:
Dinh, L.; Balooch, M. & LeMay, J.D.
Object Type:
Report
System:
The UNT Digital Library
Development and testing of insulated drillpipe
The Geothermal Research Department at Sandia National Laboratories, in collaboration with Drill Cool Systems, Inc., has worked to develop and test insulated drillpipe (IDP). IDP will allow much cooler drilling fluid to reach the bottom of the hole, making possible the use of downhole motors, electronics, and steering tools that are now unusable in high-temperature formations. Other advantages of cooler fluid include reduced degradation of drilling fluid, longer bit life, and reduced corrosion rates. The paper describes the theoretical background, laboratory testing, and field testing of IDP. Structural and thermal laboratory testing procedures and results are described. Results are given for a field test in a geothermal well, in which circulating temperatures in IDP are compared with those in conventional drillpipe (CDP) at different flow rates. A brief description of the software used to model wellbore temperature and to calculate sensitivity to IDP design differences is included, along with a comparison of calculated and measured wellbore temperatures in the field test. Analysis of mixed (IDP and CDP) drill strings and discussion of where IDP should be placed in a mixed string are presented.
Date:
January 26, 2000
Creator:
FINGER,JOHN T.; JACOBSON,RONALD D. & CHAMPNESS,A.T.
Object Type:
Article
System:
The UNT Digital Library
Diagnostics-while drilling: Reducing the cost of geothermal-produced electricity
The goal of this document is to estimate the potential impact of proposed new Diagnostics-While-Drilling technology on the cost of electricity (COE) produced with geothermal energy. A cost model that predicts the COE was developed and exercised over the range of conditions found for geothermal plants in flashed-steam, binary, and enhanced-reservoir (e.g., Hot Dry Rock) applications. The calculations were repeated assuming that DWD technology is available to reduce well costs and improve well productivity. The results indicate that DWD technology would reduce the geothermal COE by 2--31%, depending on well depth, well productivity, and the type of geothermal reservoir. For instance, for a typical 50-MW, flashed-steam geothermal power plant employing 3-MW wells, 6,000-ft deep, the model predicts an electricity cost of 4.9 cents/kwh. With the DWD technology envisioned, the electricity cost could be reduced by nearly 20%, to less than 4 cents/kwh. Such a reduction in the cost of electricity would give geothermal power a competitive edge over other types of power at many locations across the US and around the world. It is thus believed that DWD technology could significantly expand the role of geothermal energy in providing efficient, environment-friendly electric generating capacity.
Date:
January 26, 2000
Creator:
PRAIRIE,MICHAEL R. & GLOWKA,DAVID A.
Object Type:
Article
System:
The UNT Digital Library
Dynamics of Crust Dissolution and Gas Release in Tank 241-SY-101
Due primarily to an increase in floating crust layer thickness, the waste level in Hanford Tank 241-SY-101 (SY-101) has grown appreciably, and the flammable gas volume stored in the crust has become a potential hazard. To remediate gas retention in the crust and the potential for buoyant displacement gas releases from the nonconnective layer at the bottom of the tank, SY-101 will be diluted to dissolve a large fraction of the solids that allow the waste to retain gas. In this work we develop understanding of the state of the tank waste and some of its physical properties, investigate how added water will be distributed in the tank and affect the waste, and use the information to evaluate mechanisms and rates of waste solids dissolution and gas release. This work was completed to address these questions and in support of planning and development of controls for the SY-101 Surface Level Rise Remediation Project. Particular emphasis is given to dissolution of and gas release from the crust, although the effects of back-dilution on all waste layers are addressed. The magnitude and rates of plausible gas release scenarios are investigated, and it is demonstrated that none of the identified mechanisms of continuous …
Date:
January 26, 2000
Creator:
Rassat, S. D.; Stewart, C. W.; Wells, B. E.; Kuhn, W. L.; Antoniak, Z. I.; Cuta, J. M. et al.
Object Type:
Report
System:
The UNT Digital Library
The effect of adding crystalline silicotitanate on the durability, liquidus, and viscosity of simulated high-level waste glasses at Savannah River Site
This report provides a summary of the results obtained for a limited variability study for glasses containing Crystalline Silicotitanate (CST), Monosodium Titanate (MST), and either simulated Purex or HM sludge. Twenty-two glasses containing Purex sludge and three glasses containing HM sludge were fabricated and tested. The fabricated glasses were tested for durability using the 7-day Product Consistency Test (PCT) and characterized by measuring the viscosity at 1,150 C and by determining an approximate, bounding liquidus temperature. The current models used by Defense Waste Processing Facility (DWPF) for predicting durability, viscosity, and liquidus temperature were applied to all 25 glasses. The goal of this work was to identify any major problems from a glass perspective, within the scope of this effort, which could potentially preclude the use of CST at DWPF.
Date:
January 26, 2000
Creator:
Harbour, J.R.
Object Type:
Article
System:
The UNT Digital Library
Effect of defects on the critical points in YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}}
The upper and lower critical points are investigated in untwinned YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} single crystals with dilute columnar defects. Dilute columnar defects raise the upper critical point, indicating that the transition near the upper critical point is a vortex entanglement transition. The lower critical point is very sensitive to columnar defect disorder and its position can be described by a Lindemann-like criterion similar to that for melting. Dilute columnar defects induce non-linear behavior in the I-V curves of the vortex liquid state above the lower critical point, which the authors interpret as a vestige of the critical region associated with the Bose glass transition below the lower critical point.
Date:
January 26, 2000
Creator:
Kwok, W. K.; Olsson, R. J.; Karapetrov, G.; Paulis, L. M.; Moulton, W. G.; Hofman, D. J. et al.
Object Type:
Article
System:
The UNT Digital Library
Energy Matters - January/February 2000
Energy Matters is an Office of Industrial Technologies bimonthly publication on energy efficiency opportunities. This issue's focus is on reliability-centered maintenance along with articles on optimizing industrial process heating and discussion on an international motor systems management tool.
Date:
January 26, 2000
Creator:
Ericksen, E.
Object Type:
Book
System:
The UNT Digital Library
Engineering-Economic Analyses of Automotive Fuel Economy Potential in the United States
Over the past 25 years more than 20 major studies have examined the technological potential to improve the fuel economy of passenger cars and light trucks in the US. The majority has used technology/cost analysis, a combination of analytical methods from the disciplines of economics and automotive engineering. In this paper they describe the key elements of this methodology, discuss critical issues responsible for the often widely divergent estimates produced by different studies, review the history of its use, and present results from six recent assessments. Whereas early studies tended to confine their scope to the potential of proven technology over a 10-year time period, more recent studies have focused on advanced technologies, raising questions about how best to include the likelihood of technological change. The paper concludes with recommendations for further research.
Date:
January 26, 2000
Creator:
Greene, D. L.
Object Type:
Report
System:
The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Wednesday, January 26, 2000
Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date:
January 26, 2000
Creator:
Bush, Kent
Object Type:
Newspaper
System:
The Gateway to Oklahoma History