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Removal of radioisotopes from the Columbia River by natural processes

Description: Some radioisotopes are introduced into the Columbia River by return of the water used to cool the Hanford reactors. Trace amounts of both fission product and activation product radioisotopes are present and measurable by sensitive radiochemical methods to allow determination of the self-purification processes occurring as the water moves downstream. By comparing the radioisotope input at given times with the amounts present in the river after traveling downstream, a measure of the self-purifica… more
Date: April 10, 1962
Creator: Nielsen, J. M. & Perkins, R. W.
Partner: UNT Libraries Government Documents Department
open access

Effect of several surface treatments on the strength of a glass ceramic-to-metal seal

Description: Test shells of Inconel 625, Inconel 718, 21-6-9 stainless steel, and Hastelloy, C-276 were plasma and/or chemically cleaned before sealing with a multi-component glass-ceramic-to-metal seal was evaluated using a hydrostatic burst test. The results show that plasma cleaning can be used to increase the hydrostatic burst strength and hermeticity of a glass ceramic-to-metal seal.
Date: February 10, 1982
Creator: Kramer, D P; Salerno, R F & Egleston, E E
Partner: UNT Libraries Government Documents Department
open access

Deactivation by Carbon of Iron Catalysts for Indirect Liquefaction

Description: Although promoted cobalt and iron catalysts for Fischer-Tropsch (FT) synthesis of gasoline feedstock were first developed more than three decades ago, a major technical problem still limiting the commercial use of these catalysts today is carbon deactivation. This report describes recent progress in a fundamental, three-year investigation of carbon formation and its effects on the activity and selectivity of promoted iron catalysts for FT synthesis, the objectives of which are to: determine rat… more
Date: January 10, 1991
Creator: Bartholomew, C. H.
Partner: UNT Libraries Government Documents Department
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A Study of Advanced Materials for Gas Turbine Coatings at Elevated Temperatures Using Selected Microstructures and Characteristic Environments for Syngas Combustion

Description: Thermal barrier coatings (TBCs) that can be suitable for use in industrial gas turbine engines have been processed and compared with electron beam physical vapor deposition (EBPVD) microstructures for applications in advanced gas turbines that use coal-derived synthesis gas. Thermo-physical properties have been evaluated of the processed air plasma sprayed TBCs with standard APS-STD and vertically cracked APS-VC coatings samples up to 1300 C. Porosity of these selected coatings with related mic… more
Date: February 10, 2011
Creator: Diwan, Ravinder; Mensah, Patrick; Li, Guoqiang; Uppu, Nalini; Akwaboa, Strphen; Silva, Monica et al.
Partner: UNT Libraries Government Documents Department
open access

ACTUAL-WASTE TESTING OF ULTRAVIOLET LIGHT TO AUGMENT THE ENHANCED CHEMICAL CLEANING OF SRS SLUDGE

Description: In support of Savannah River Site (SRS) tank closure efforts, the Savannah River National Laboratory (SRNL) conducted Real Waste Testing (RWT) to evaluate Enhanced Chemical Cleaning (ECC), an alternative to the baseline 8 wt% oxalic acid (OA) chemical cleaning technology for tank sludge heel removal. ECC utilizes a more dilute OA solution (2 wt%) and an oxalate destruction technology using ozonolysis with or without the application of ultraviolet (UV) light. SRNL conducted tests of the ECC proc… more
Date: July 10, 2012
Creator: Martino, C.; King, W. & Ketusky, E.
Partner: UNT Libraries Government Documents Department
open access

Boundary-layer control for reducing deposition of solids at a geothermal nozzle wall

Description: Deposition of solids at the wall of a nozzle used to expand geothermal brine may be accounted for by a hydrodynamic model describing eddy formation near the wall. A conceptual design of a nozzle with injection of an annular ring of fluid at the wall is presented.
Date: June 10, 1976
Creator: Homsy, Robert V.
Partner: UNT Libraries Government Documents Department
open access

Morphological aspects of surface reactions. Progress report, March 1993--March 1994

Description: This work focuses on substrate morphology and on fragments synthesized by thermal, electron, and photon activation. The following work is complete: (1) Low energy electron diffraction, Auger electron spectroscopy and scanning tunneling microscopy were used to determine the local morphology of rhodium films on titania. (2) A new tool was developed for diagnosing surface reactions that involve C-H bond cleavage -- predosed oxygen TPD (POTPD), a technique based on scavenging surface H(a) by small … more
Date: January 10, 1994
Creator: White, J. M.
Partner: UNT Libraries Government Documents Department
open access

Improved Radiation Dosimetry/Risk Estimates to Facilitate Environmental Management of Plutonium Contaminated Sites

Description: Our phase-II research relates to evaluating health risks associated with inhaled plutonium (Pu). Our current research objectives are as follows: (1) to extend our stochastic model for deposition of plutonium (Pu) in the respiratory tract to include additional key variability and uncertainty; (2) to generate and analyze risk distributions for deterministic effects in the lung from inhaled Pu that reflect risk model uncertainty; (3) to acquire an improved understanding of key physiological effect… more
Date: July 10, 2002
Creator: Scott, Bobby R.; Cheng, Yung-Sung; Zhou, Yue; Tokarskaya, Zoya B. & Zhuntova, Galina V.
Partner: UNT Libraries Government Documents Department
open access

Calcite Fluid Inclusion, Paragenetic, and Oxygen Isotopic Records of Thermal Event(s) at Yucca Mountain, Nevada

Description: Yucca Mountain, Nevada, is under consideration as a potential high-level radioactive waste repository situated above the water table in 12.7 Ma tuffs. A wealth of textural and geochemical evidence from low-temperature deposits of calcite and silica, indicates that their genesis is related to unsaturated zone (UZ) percolation and that the level of the potential repository has never been saturated. Nonetheless, some scientists contend that thermal waters have periodically risen to the surface dep… more
Date: August 10, 2000
Creator: Peterman, B. & Moscati, R.
Partner: UNT Libraries Government Documents Department
open access

Impermeable Thin Al2O3 Overlay for TBC Protection From Sulfate and Vanadate Attack in Gas Turbines Quarterly Report

Description: In order to improve the hot corrosion resistance of yttria-stabilized zirconia (YSZ), an Al{sub 2}O{sub 3} overlay has been deposited on the surface of YSZ by electron-beam physical vapor deposition. Currently, hot corrosion tests were performed on the YSZ coatings with and without Al{sub 2}O{sub 3} overlay in molten salt mixture (Na{sub 2}SO{sub 4} + 0 {approx} 15wt%V{sub 2}O{sub 5}) at 950 C in order to investigate the effect of amount of vanadate on the hot corrosion behaviors. The results s… more
Date: June 10, 2003
Creator: Mao, Scott X.
Partner: UNT Libraries Government Documents Department
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Emerging materials for solar cell applications: electrodeposited CdTe. Second quarter report, May 16-August 15, 1980

Description: Work was centered about improving electroplating processes and cell fabrication techniques, with emphasis being given to three differing n-CdTe/Au Schottky configurations. The highest values of efficiency-related parmeters achieved with a simulated solar irradiation of 100 mW/cm/sup 2/ were 0.57V for open circuit voltage, 0.6 for fill factor, and 6 mA/cm/sup 2/ for short circuit current. Four important parameters are known to control the quality of the Monosolar electrodeposition process and re… more
Date: September 10, 1980
Creator: Basol, B. & Stafsudd, O.
Partner: UNT Libraries Government Documents Department
open access

Design and construction of a RHEED diffractometer with energy resolution capability

Description: In this work the author describes the set up of a UHV system to study the growth of ultra-thin metallic films on a silicon substrate under RHEED conditions. However, a new feature has been added to the normal RHEED apparatus. Because the phosphor screen acts as a high pass filter for the scattered electrons, energy filtering is normally excluded from RHEED techniques. In the experimental apparatus, a biased Faraday collector has been added to measure only the elastically scattered part of the d… more
Date: February 10, 1995
Creator: Formas, R.
Partner: UNT Libraries Government Documents Department
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