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Development of novel copper-based sorbents for hot-gas cleanup. [Quarterly] technical report, September 1--November 30, 1993
The objective of this investigation is to evaluate two novel copper-based sorbents, namely copper-chromium and copper-cerium, for their effectiveness in removing hydrogen sulfide from fuel gas in the temperature range of 650{degree} to 850{degree}C. Such high temperatures will be required for the new generation of gas turbines (inlet >750{degree}C) in Integrated Gasification Combined Cycle (IGCC) systems. The effect of pre-reduction on the performance of the sorbents as well as the rate of different reactions occurring in cyclic sulfidation/regeneration, were studied in a thermogravimetric analyzer (TGA). Sulfidation was conducted with and without H{sub 2} and H{sub 2}O, and with and without pre-reduction in H{sub 2} or H{sub 2}/H{sub 2}O. The results of these tests indicate that reduction and regeneration of both sorbents occurs rapidly. Sulfidation of CuCr{sub 2}O{sub 4}, in H{sub 2}O-free and H{sub 2}-/H{sub 2}O-free gas indicates the possible sulfidation of both copper and chromium. Small quantities of SO{sub 2}, were released during sulfidation suggesting the possible oxidation of H{sub 2}S by the sorbent. Regeneration of the CuCr{sub 2}O{sub 4} was complete while regeneration of the CuO-CeO{sub 2} indicated possible limited sulfate formation.
Date:
March 1, 1994
Creator:
Abbasian, J.; Hill, A. H.; Flytzani-Stephanopoulos, M. & Li Li
Object Type:
Report
System:
The UNT Digital Library
Sulfur removal in advanced two-staged pressurized fluidized-bed combustion; [Quarterly] report, September 1--November 1993
The objective of this study is to obtain data on the rates of reaction between hydrogen sulfide (H{sub 2}S) and uncalcined calcium-based sorbents under operating conditions relevant to first stage (carbonizer) of Advanced Two-Stage Pressurized Fluidized-Bed Combustors (PFBC). In these systems the CO{sub 2} partial pressure in the first stage generally exceeds the equilibrium value for calcium carbonate decomposition. Therefore, removal of sulfur compounds takes place through the reaction between H{sub 2}S and calcium carbonate. To achieve this objective, the rates of reaction between hydrogen sulfide and uncalcined calcium-based sorbents will be determined by conducting tests in pressurized thermogravimetric analyzer (TGA) and high-pressure/high-temperature fluidized-bed reactor (HPTR) units. The effects of sorbent type, sorbent particle size, reactor temperature and pressure, and CO{sub 2} and H{sub 2}S partial pressures on the sulfidation reaction rate will be determined. A pressurized TGA unit has been purchased by IGT for use in this project.
Date:
March 1, 1994
Creator:
Abbasian, Javad; Hill, Andy H.; Wangerow, James R. & Rue, David M.
Object Type:
Report
System:
The UNT Digital Library
Spent Fuel Background Report Volume I
This report is an overview of current spent nuclear fuel management in the DOE complex. Sources of information include published literature, internal DOE documents, interviews with site personnel, and information provided by individual sites. Much of the specific information on facilities and fuels was provided by the DOE sites in response to the questionnaire for data for spent fuels and facilities data bases. This information is as accurate as is currently available, but is subject to revision pending results of further data calls. Spent fuel is broadly classified into three categories: (a) production fuels, (b) special fuels, and (c) naval fuels. Production fuels, comprising about 80% of the total inventory, are those used at Hanford and Savannah River to produce nuclear materials for defense. Special fuels are those used in a wide variety of research, development, and testing activities. Special fuels include fuel from DOE and commercial reactors used in research activities at DOE sites. Naval fuels are those developed and used for nuclear-powered naval vessels and for related research and development. Given the recent DOE decision to curtail reprocessing, the topic of main concern in the management of spent fuel is its storage. Of the DOE sites that have …
Date:
March 1, 1994
Creator:
Abbott, D.
Object Type:
Report
System:
The UNT Digital Library
Spent Fuel Background Report Volume II
This Volume II contains tables that describe DOE fuel storage facilities and the fuel contained in those facilities.
Date:
March 1, 1994
Creator:
Abbott, D.
Object Type:
Report
System:
The UNT Digital Library
[RE: Urgent Information RE: May, 1994 Regional Institute Directors' Meeting]
Photocopy of a memo from Julie Able, program associate for the Getty Center for Education in the Arts, to the Regional Institute Directors. The memo is in regards to urgent information for the May, 1994 regional institute directors' meeting. Due to unforeseen scheduling obstacles, Leilani Lattin Duke will be unable to attend the director's meeting on Friday, May 7th, 1994. To accommodate this, Duke requests that the directors' meeting in Laguna Beach be moved back one day.
Date:
March 24, 1994
Creator:
Abel, Julie
Object Type:
Letter
System:
The UNT Digital Library
Spectrochemical Investigation of Preferential Solvation. 2. Compatibility of Thermodynamic Models versus Spectrofluorometric Probe Methods for Tautomeric Solutes Dissolved in Binary Mixtures
Article discussing spectrochemical investigations of preferential solvation and the compatibility of thermodynamic models versus spectrofluorometric probe methods for tautomeric solutes dissolved in binary mixtures.
Date:
March 1, 1994
Creator:
Acree, William E. (William Eugene); Wilkins, Denise C.; Tucker, Sheryl A. (Sheryl Ann); Griffin, Jason M. & Powell, Joyce R.
Object Type:
Article
System:
The UNT Digital Library
Using the internet in middle schools: A model for success
Los Alamos National Laboratory (LANL) developed a model for school networking using Los Alamos Middle School as a testbed. The project was a collaborative effort between the school and the Laboratory. The school secured administrative funding for hardware and software; and LANL provided the network architecture, installation, consulting, and training. The model is characterized by a computer classroom linked with two GatorBoxes and a UNIX-based workstation server. Six additional computers have also been networked from a teacher learning center and the library. The model support infrastructure includes: local school system administrators/lead teachers, introductory and intermediate hands-on teacher learning, teacher incentives for involvement and use, opportunities for student training and use, and ongoing LANL consulting. Formative evaluation data reveals that students and teachers alike are finding the Internet to be a tool that crosses disciplines, allowing them to obtain more, timely information and to communicate with others more effectively and efficiently. A lead teacher`s enthusiastic comments indicate some of the value gained: ``We have just scratched the surface. Each day someone seems to find something new and interesting on the Internet. The possibilities seem endless.``
Date:
March 1, 1994
Creator:
Addessio, B.; Boorman, M.; Eker, P.; Fletcher, K.; Judd, B.; Trainor, M. et al.
Object Type:
Article
System:
The UNT Digital Library
Development of a cost effective environment compliance technology for stripper brine wells. [Annual] report, January 1, 1993--December 31, 1993
The specific objective of the research is to demonstrate that the characteristics of wastewater from stripper oil wells and marginal gas wells are sufficiently similar to be treated under a standardized treatment methodology, that the environmental impacts of the discharge of treated brines from both stripper oil and marginal gas wells can be adequately regulated, and that the inclusion of marginal gas wells in the same category as stripper oil wells is appropriate, especially for wells operating in the Appalachian Basin. The work accomplished during 1992 for both the field-scale and the laboratory-scale treatment facilities focused on iron removal from the field and synthetic brines. The laboratory work also included single-element kinetics studies to determine the effect of one metal on another with respect to the rates of the various reactions. The laboratory process studies investigated such parameters as the sand bed thickness, the temperature of the system, the angle of the aeration unit, and the presence of the retention tank. All of these laboratory parametric studies provided insight into how each component of the treatment process contributes to the removal of iron from the synthetic brine. Similar studies have begun for investigating copper removal effectiveness. As for the field …
Date:
March 8, 1994
Creator:
Adewumi, M. A.; Watson, R. W.; Tian, S.; Heckman, S.; Safargar, S. & Drielinger, I.
Object Type:
Report
System:
The UNT Digital Library
A tool for debugging internet multicast routing
In this paper the authors describe a debugging tool that is an effective means of analyzing problems with multicast packet routing in a network. Multicast packet routing is a source-driven distributed calculation performed by the routers in a multicast network. The routes taken by multicast packets are difficult to predict manually due to the large number of variables that must be considered. The multicast route debugging tool allows off-line investigation of the route taken by a multicast packet and the effects of network modifications on that route. The tool has already proved useful in debugging the problems that have occurred in the experimental Internet Multicast Backbone. The multicast route debugging tool currently predicts multicast routes of packets using the distance-vector truncated-broadcast algorithm implemented for Internet multicast traffic. They will be upgrading the tool to allow the user to choose other multicast routing algorithms.
Date:
March 1, 1994
Creator:
Agarwal, D. & Floyd, S.
Object Type:
Article
System:
The UNT Digital Library
Spectral radiative heat transfer in coal furnaces using a hybrid technique
A hybrid technique has been developed to solve three-dimensional spectral radiation transport equations for absorbing, emitting and anisotropically scattering media. An optimal mix of computational speed and accuracy is obtained by combining the discrete ordinate method (S{sub 4}), modified differential approximation (MDA) and P{sub 1} approximation for use in different range of optical thicknesses. The technique is used in conjunction with a char burnout model and spectroscopic data for H{sub 2}O, CO{sub 2}, CO, char, soot and ash to determine the influence of ash composition, ash content and coal preparation on furnace heat absorption.
Date:
March 1, 1994
Creator:
Ahluwalia, R. K. & Im, K. H.
Object Type:
Report
System:
The UNT Digital Library
The ATLAS Positron Experiment -- APEX
APEX -- the ATLAS Positron Experiment -- is designed to measure electrons and positrons emitted in heavy-ion collisions. Its scientific goal is to gain insight into the puzzling positron-line phenomena observed at the GSI Darmstadt. It is in operation at the ATLAS accelerator at Argonne National Lab. The assembly of the apparatus is finished and beginning 1993 the first positrons produced in heavy-ion collisions were observed. The first full scale experiment was carried out in December 1993, and the data are currently being analyzed. In this paper, the principles of operation are explained and a status report on the experiment is given.
Date:
March 1, 1994
Creator:
Ahmad, I.; Back, B. B.; Betts, R. R.; Dunford, R.; Kutschera, W.; Rhein, M. D. et al.
Object Type:
Article
System:
The UNT Digital Library
Westinghouse radiological containment guide
This document provides uniform guidance for Westinghouse contractors on the implementation of radiological containments. This document reflects standard industry practices and is provided as a guide. The guidance presented herein is consistent with the requirements of the DOE Radiological Control Manual (DOE N 5480.6). This guidance should further serve to enable and encourage the use of containments for contamination control and to accomplish the following: Minimize personnel contamination; Prevent the spread of contamination; Minimize the required use of protective clothing and personal protective equipment; Minimize the generation of waste.
Date:
March 1, 1994
Creator:
Aitken, S. B.; Brown, R. L.; Cantrell, J. R. & Wilcox, D. P.
Object Type:
Report
System:
The UNT Digital Library
TMI-2 nozzle examinations performed at the Idaho National Engineering Laboratory
As part of the Three Mile Island Unit 2 (TMI-2) Vessel Investigation Project, under the auspices of the Organization for Economic Cooperation and Development, examinations were performed at the Idaho National Engineering Laboratory on eight nozzles and one guide tube from the TMI-2 reactor vessel. This document describes the examination methodology, summarizes the examination results, and presents interpretations of the results as they relate to the damage to the reactor vessel and to the development of a core relocation scenario. Not all examinations originally proposed as part of this program were completed due to facility problems at the INEL. Consequently, only the results of completed aspects of the examination program are presented.
Date:
March 1, 1994
Creator:
Akers, D. W. & Schuetz, B. K.
Object Type:
Report
System:
The UNT Digital Library
Examination of relocated fuel debris adjacent to the lower head of the TMI-2 reactor vessel
As part of the Three Mile Island Unit 2 (TMI-2) Vessel Investigation Project, funded by the Organization for Economic Cooperation and Development, physical, metallurgical, and radiochemical examinations were performed on samples of previously molten material that had relocated to the lower plenum of the TMI-2 reactor during the accident of 28 March 1979. This report presents the results of those examinations and some limited analysis of these results as required for the interpretation of the data. Principal conclusions of the examinations are that the bulk lower head debris is homogeneous and composed primarily of (U,Zr)O{sub 2}. This molten material reached temperatures greater than 2,600 C and probably reached the lower head as a liquid or slurry at temperatures below the peak temperature. A debris bed was formed, which was composed of particular debris above a monolithic melt that solidified on the lower head.
Date:
March 1, 1994
Creator:
Akers, D. W.; Jensen, S. M. & Schuetz, B. K.
Object Type:
Report
System:
The UNT Digital Library
Release of radionuclides and chelating agents from cement-solidified decontamination low-level radioactive waste collected from the Peach Bottom Atomic Power Station Unit 3
As part of a study being performed for the Nuclear Regulatory Commission (NRC), small-scale waste-form specimens were collected during a low oxidation-state transition-metal ion (LOMI)-nitric permanganate (NP)-LOMI solidification performed in October 1989 at the Peach Bottom Atomic Power Station Unit 3. The purpose of this program was to evaluate the performance of cement-solidified decontamination waste to meet the low-level waste stability requirements defined in the NRC`s ``Technical Position on Waste Form,`` Revision 1. The samples were acquired and tested because little data have been obtained on the physical stability of actual cement-solidified decontamination ion-exchange resin waste forms and on the leachability of radionuclides and chelating agents from those waste forms. The Peach Bottom waste-form specimens were subjected to compressive strength, immersion, and leach testing in accordance with the NRC`s ``Technical Position on Waste Form,`` Revision 1. Results of this study indicate that the specimens withstood the compression tests (>500 psi) before and after immersion testing and leaching, and that the leachability indexes for all radionuclides, including {sup 14}C, {sup 99}{Tc}, and {sup 129}I, are well above the leachability index requirement of 6.0, required by the NRC`s ``Technical Position on Waste Form,`` Revision 1.
Date:
March 1, 1994
Creator:
Akers, D. W.; Kraft, N. C. & Mandler, J. W.
Object Type:
Report
System:
The UNT Digital Library
The Boerne Star (Boerne, Tex.), Vol. 90, No. 9, Ed. 1 Wednesday, March 2, 1994
Weekly newspaper from Boerne, Texas that includes local, state, and national news along with advertising.
Date:
March 2, 1994
Creator:
Aldridge, Leon
Object Type:
Newspaper
System:
The Portal to Texas History
The Boerne Star (Boerne, Tex.), Vol. 90, No. 10, Ed. 1 Wednesday, March 9, 1994
Weekly newspaper from Boerne, Texas that includes local, state, and national news along with advertising.
Date:
March 9, 1994
Creator:
Aldridge, Leon
Object Type:
Newspaper
System:
The Portal to Texas History
The Boerne Star (Boerne, Tex.), Vol. 90, No. 11, Ed. 1 Wednesday, March 16, 1994
Weekly newspaper from Boerne, Texas that includes local, state, and national news along with advertising.
Date:
March 16, 1994
Creator:
Aldridge, Leon
Object Type:
Newspaper
System:
The Portal to Texas History
The Boerne Star (Boerne, Tex.), Vol. 90, No. 12, Ed. 1 Wednesday, March 23, 1994
Weekly newspaper from Boerne, Texas that includes local, state, and national news along with advertising.
Date:
March 23, 1994
Creator:
Aldridge, Leon
Object Type:
Newspaper
System:
The Portal to Texas History
The Boerne Star (Boerne, Tex.), Vol. 90, No. 13, Ed. 1 Wednesday, March 30, 1994
Weekly newspaper from Boerne, Texas that includes local, state, and national news along with advertising.
Date:
March 30, 1994
Creator:
Aldridge, Leon
Object Type:
Newspaper
System:
The Portal to Texas History
Mitigation of Tank 241-SY-101 by pump mixing: Results of testing phases A and B
A spare mixing pump from the Hanford Grout Program was installed in Hanford double-shell waste Tank 241-SY-101 on July 3, 1993, after being modified to take advantage of waste stratification. It was anticipated that pump mixing would prevent large episodic flammable gas releases that had been occurring about every 100-150 days. A cautious initial test plan, called Phase A, was run to find how the pump and tank would behave in response to very brief and gentle pump operation. No large gas releases were triggered, and the pump performed well except for two incidents of nozzle plugging. On October 21, 1993, the next test series, Phase B, began, and the pump was applied more aggressively to mix the tank contents and mitigate uncontrolled gas releases. Orienting the pump in new directions released large volumes of gas and reduced the waste level to a near-record low. Results of the entire period from pump installation to the end of Phase B on December 17, 1993, are presented in detail in this document. Though long-term effects require further evaluation, we conclude from these data that the jet mixer pump is an effective means of controlling flammable gas release and that it has met …
Date:
March 1, 1994
Creator:
Allemann, R. T.; Antoniak, Z. I.; Chvala, W. D.; Friley, J. R.; Gregory, W. B.; Hudson, J. D. et al.
Object Type:
Report
System:
The UNT Digital Library
Determining Uranium Speciation in Contaminated Soils by Molecular Spectroscopic Methods: Examples From the Uranium in Soils Integrated Demonstration
The US Department of Energy`s former uranium production facility located at Fernald, OH (18 mi NW of Cincinnati) is the host site for an Integrated Demonstration for remediation of uranium-contaminated soils. A wide variety of source terms for uranium contamination have been identified reflecting the diversity of operations at the facility. Most of the uranium contamination is contained in the top {approximately}1/2 m of soil, but uranium has been found in perched waters indicating substantial migration. In support of the development of remediation technologies and risk assessment, we are conducting uranium speciation studies on untreated and treated soils using molecular spectroscopies. Untreated soils from five discrete sites have been analyzed. We have found that {approximately}80--90% of the uranium exists as hexavalent UO{sub 2}{sup 2+} species even though many source terms consisted of tetravalent uranium species such as UO{sub 2}. Much of the uranium exists as microcrystalline precipitates (secondary minerals). There is also clear evidence for variations in uranium species from the microscopic to the macroscopic scale. However, similarities in speciation at sites having different source terms suggest that soil and groundwater chemistry may be as important as source term in defining the uranium speciation in these soils. Characterization of treated …
Date:
March 1, 1994
Creator:
Allen, P. G.; Berg, J. M.; Chisholm-Brause, C. J.; Conradson, S. D.; Donohoe, R. J.; Morris, D. E. et al.
Object Type:
Article
System:
The UNT Digital Library
The computation of cloud base height from paired whole-sky imaging cameras
A major goal for global change studies is to improve the accuracy of general circulation models (GCMs) capable of predicting the timing and magnitude of greenhouse gas-induced global warming. Research has shown that cloud radiative feedback is the single most important effect determining the magnitude of possible climate responses to human activity. Of particular value to reducing the uncertainties associated with cloud-radiation interactions is the measurement of cloud base height (CBH), both because it is a dominant factor in determining the infrared radiative properties of clouds with respect to the earth`s surface and lower atmosphere and because CBHs are essential to measuring cloud cover fraction. We have developed a novel approach to the extraction of cloud base height from pairs of whole sky imaging (WSI) cameras. The core problem is to spatially register cloud fields from widely separated WSI cameras; this complete, triangulation provides the CBH measurements. The wide camera separation (necessary to cover the desired observation area) and the self-similarity of clouds defeats all standard matching algorithms when applied to static views of the sky. To address this, our approach is based on optical flow methods that exploit the fact that modern WSIs provide sequences of images. We will …
Date:
March 1, 1994
Creator:
Allmen, M. C. & Kegelmeyer, W. P. Jr.
Object Type:
Report
System:
The UNT Digital Library
Fluorescence detection of single molecules using pulsed near-field optical excitation and time correlated photon counting
Pulsed excitation, time correlated single photon counting and time gated detection are used in near-field optical microscopy to enhance fluorescence images and measure the fluorescence lifetimes of single molecules of Rhodamine 6G on silica surfaces. Time gated detection is used to reject prompt scattered background and to improve the image signal to noise ratio. The excited state lifetime of a single Rhodamine 6G molecule is found to depend on the position of the near-field probe. We attribute the lifetime variations to spontaneous emission rate alterations by the fluorescence reflected from and quenching by the aluminum coated probe.
Date:
March 1, 1994
Creator:
Ambrose, W. P.; Goodwin, P. M.; Martin, J. C. & Keller, R. A.
Object Type:
Article
System:
The UNT Digital Library