Advanced neutron source reactor conceptual safety analysis report, three-element-core design: Chapter 15, accident analysis (open access)

Advanced neutron source reactor conceptual safety analysis report, three-element-core design: Chapter 15, accident analysis

In order to utilize reduced enrichment fuel, the three-element-core design for the Advanced Neutron Source has been proposed. The proposed core configuration consists of inner, middle, and outer elements, with the middle element offset axially beneath the inner and outer elements, which are axially aligned. The three-element-core RELAP5 model assumes that the reactor hardware is changed only within the core region, so that the loop piping, heat exchangers, and pumps remain as assumed for the two-element-core configuration. To assess the impact of changes in the core region configuration and the thermal-hydraulic steady-state conditions, the safety analysis has been updated. This report gives the safety margins for the loss-of-off-site power and pressure-boundary fault accidents based on the RELAP5 results. AU margins are greater for the three-element-core simulations than those calculated for the two-element core.
Date: February 1, 1996
Creator: Chen, N. C. J.; Wendel, M. W.; Yoder, G. L. & Harrington, R. M.
Object Type: Report
System: The UNT Digital Library
Advanced NMR-based techniques for pore structure analysis of coal. Final project report (open access)

Advanced NMR-based techniques for pore structure analysis of coal. Final project report

During the 3 year term of the project, new methods have been developed for characterizing the pore structure of porous materials such as coals, carbons, and amorphous silica gels. In general, these techniques revolve around; (1) combining multiple techniques such as small-angle x-ray scattering (SAXS) and adsorption of contrast-matched adsorbates or {sup 129}Xe NMR and thermoporometry (the change in freezing point with pore size), (2) combining adsorption isotherms over several pressure ranges to obtain a more complete description of pore filling, or (3) applying NMR ({sup 129}Xe, {sup 14}N{sub 2}, {sup 15}N{sub 2}) techniques with well-defined porous solids with pores in the large micropore size range (>1 nm).
Date: February 1, 1996
Creator: Smith, D. M.; Hua, D. W. & Earl, W.
Object Type: Report
System: The UNT Digital Library
Advanced Recovery and Integrated Extraction System (ARIES) program plan. Rev. 1 (open access)

Advanced Recovery and Integrated Extraction System (ARIES) program plan. Rev. 1

The Advanced Recovery and Integrated Extraction System (ARIES) demonstration combines various technologies, some of which were/are being developed under previous/other Department of Energy (DOE) funded programs. ARIES is an overall processing system for the dismantlement of nuclear weapon primaries. The program will demonstrate dismantlement of nuclear weapons and retrieval of the plutonium into a form that is compatible with long term storage and that is inspectable in an unclassified form appropriate for the application of traditional international safeguards. The success of the ARIES demonstration would lead to the development of a transportable modular or other facility type systems for weapons dismantlement to be used at other DOE sites as well as in other countries.
Date: February 2, 1996
Creator: Nelson, T.O.; Massey, P.W. & Cremers, T.L.
Object Type: Report
System: The UNT Digital Library
Advanced separation technology for flue gas cleanup. Quarterly technical report No. 15 (open access)

Advanced separation technology for flue gas cleanup. Quarterly technical report No. 15

The objective of this work is to develop a novel system for regenerable SO{sub 2} and NO{sub x} scrubbing of flue gas that focuses on (1) a novel method for regeneration of spent SO{sub 2} scrubbing liquor and (2) novel chemistry for reversible absorption of NO{sub x}. In addition, high efficiency hollow fiber contactors (HFC) are proposed as the devices for scrubbing the SO{sub 2} and NO{sub x} from the flue gas. The system will be designed to remove more than 95% of the SO{sub x} and more than 75% of the NO{sub x} from flue gases typical of pulverized coal-fired power plants at a cost that is at least 20% less than combined wet limestone scrubbing of SO{sub x} and selective catalytic reduction of NO{sub x}. In addition, the process will make only marketable byproducts, if any (no waste streams). Our approach is to reduce the capital cost by using high efficiency hollow fiber devices for absorbing and desorbing the SO{sub 2} and NO{sub x}. We will also introduce new process chemistry to minimize traditionally well-known problems with SO{sub 2} and NO{sub x} absorption and desorption. For example, we will extract the SO{sub 2} from the aqueous scrubbing liquor …
Date: February 1, 1996
Creator: Bhown, A. S.; Pakala, N.; Riggs, T. & Tagg, T.
Object Type: Report
System: The UNT Digital Library
Advanced turbine systems program conceptual design and product development. Topical report, April 1995 (open access)

Advanced turbine systems program conceptual design and product development. Topical report, April 1995

Allison Engine Company has developed and verified key combustion system technologies to satisfy ATS Phase 2 performance requirements. These activities include the following: demonstration test of an ultra-lean premix module meeting the ATS 8 ppm NOx goal using natural gas fuel; design and fabrication of a second generation premix module for bench test evaluation; bench test verification of catalytically enhanced combustion; and preliminary design of the transition section that guides the combustor discharge flow from the external combustor to the turbine inlet. Allison has been executing a systematic approach in developing the combustion system technologies to insure that the ATS engine includes the benefits of advanced material and low NOx combustion technologies without placing undue risk on the overall engine development program. New technology is most easily assimilated in discrete evolutionary stages; thus Allison has structured the combustion system development plan with a series of increasingly demanding performance evaluations that demonstrate the suitability of the individual technology. The discussion summarizes the progress made in bringing advanced combustion technology to the ATS.
Date: February 1, 1996
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Advanced turbine systems - research and development of thermal barrier coatings technology: 2nd bimonthly report, February 1996 (open access)

Advanced turbine systems - research and development of thermal barrier coatings technology: 2nd bimonthly report, February 1996

Objective of the ATS program is the development of ultra-highly efficient, environmentally superior, and cost-competitive gas turbine systems, with long, less cyclic operating profiles than aircraft gas turbine engines. Durability and performance demands of ATS can be achieved by means of thermal barrier coatings. Phase I (program plan) is complete. Phase II is in progress.
Date: February 1, 1996
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Advances in oxide-confined vertical cavity lasers (open access)

Advances in oxide-confined vertical cavity lasers

We review the advances made in device fabrication, structure, and performance of vertical-cavity surface emitting lasers (VCSELs) which incorporate the selective oxidation of AlGaAs.
Date: February 1, 1996
Creator: Choquette, K. D.; Schneider, R. P., Jr.; Lear, K. L.; Geib, K. M.; Hou, H. Q.; Chui, H. C. et al.
Object Type: Article
System: The UNT Digital Library
Aerogel commercialization pilot project. Final program report (open access)

Aerogel commercialization pilot project. Final program report

Aerogels are extremely light weight, high surface area, very insulative materials that offer many potential improvements to commercial products. Aerogels have been the subject of extensive research at Department of Energy Laboratories and have been considered one of the technology most ready for commercialization. However, commercialization of the technology had been difficult for the National Laboratories since end users were not interested in the high temperature and high pressure chemical processes involved in manufacturing the raw material. Whereas, Aerojet as a supplier of rocket fuels, specialty chemicals and materials had the manufacturing facilities and experience to commercially produce aerogel-type products. Hence the TRP provided a link between the technology source (National Laboratories), the manufacturing (Aerojet) and the potential end users (other TRP partners). The program successfully produced approximately 500 ft{sup 2} of organic aerogel but failed to make significant quantities of silica aerogel. It is significant that this production represents both the largest volume and biggest pieces of organic aerogel ever produced. Aerogels, available from this program, when tested in several prototype commercial products were expected to improve the products performance, but higher than expected projected production costs for large scale manufacture of aerogels has limited continued commercial interest from …
Date: February 13, 1996
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Aging management guideline for commercial nuclear power plants - tanks and pools (open access)

Aging management guideline for commercial nuclear power plants - tanks and pools

Continued operation of nuclear power plants for periods that extend beyond their original 40-year license period is a desirable option for many U.S. utilities. U.S. Nuclear Regulatory Commission (NRC) approval of operating license renewals is necessary before continued operation becomes a reality. Effective aging management for plant components is important to reliability and safety, regardless of current plant age or extended life expectations. However, the NRC requires that aging evaluations be performed and the effectiveness of aging management programs be demonstrated for components considered within the scope of license renewal before granting approval for operation beyond 40 years. Both the NRC and the utility want assurance that plant components will be highly reliable during both the current license term and throughout the extended operating period. In addition, effective aging management must be demonstrated to support Maintenance Rule (10 CFR 50.65) activities.
Date: February 1, 1996
Creator: Blocker, E.; Smith, S.; Philpot, L. & Conley, J.
Object Type: Report
System: The UNT Digital Library
Aging of safety class 1E transformers in safety systems of nuclear power plants (open access)

Aging of safety class 1E transformers in safety systems of nuclear power plants

This report discusses aging effects on safety-related power transformers in nuclear power plants. It also evaluates maintenance, testing, and monitoring practices with respect to their effectiveness in detecting and mitigating the effects of aging. The study follows the US Nuclear Regulatory Commission`s (NRC`s) Nuclear Plant-Aging Research approach. It investigates the materials used in transformer construction, identifies stressors and aging mechanisms, presents operating and testing experience with aging effects, analyzes transformer failure events reported in various databases, and evaluates maintenance practices. Databases maintained by the nuclear industry were analyzed to evaluate the effects of aging on the operation of nuclear power plants.
Date: February 1, 1996
Creator: Roberts, E. W.; Edson, J. L. & Udy, A. C.
Object Type: Report
System: The UNT Digital Library
An algorithm for image clusters detection and identification based on color for an autonomous mobile robot (open access)

An algorithm for image clusters detection and identification based on color for an autonomous mobile robot

An algorithm for detection and identification of image clusters or {open_quotes}blobs{close_quotes} based on color information for an autonomous mobile robot is developed. The input image data are first processed using a crisp color fuszzyfier, a binary smoothing filter, and a median filter. The processed image data is then inputed to the image clusters detection and identification program. The program employed the concept of {open_quotes}elastic rectangle{close_quotes}that stretches in such a way that the whole blob is finally enclosed in a rectangle. A C-program is develop to test the algorithm. The algorithm is tested only on image data of 8x8 sizes with different number of blobs in them. The algorithm works very in detecting and identifying image clusters.
Date: February 1, 1996
Creator: Uy, D.L.
Object Type: Report
System: The UNT Digital Library
Algorithms for PAC learning of functions with smoothness properties (open access)

Algorithms for PAC learning of functions with smoothness properties

We present three computationally efficient algorithms for Probably and Approximately Correct (PAC) learning of an unknown function f: [0, 1]{sup d} {r_arrow} [0,1], based on finite samples. The function f is chosen from the family F {intersection} C([0,1]{sup d}) or F {intersection} L{sup {infinity}} ([0,1]{sup d}), where F has either bounded modulus of smoothness or bounded capacity or both. Three function estimators based on: local averaging; nearest neighbor rule; and Nadaraya-Watson estimator, all computed using the Haar system, are analyzed. With no preprocessing of the sample, estimated function value at a given point can be computed in O(n) time. With preprocessing, the first and third estimators can be computed in O((log n){sup d}) time using a range-tree precomputed in O(dn(log n){sup d}) time.
Date: February 1, 1996
Creator: Rao, N.S.V. & Protopopescu, V.A.
Object Type: Article
System: The UNT Digital Library
Alkaline oxide conversion coatings for aluminum alloys (open access)

Alkaline oxide conversion coatings for aluminum alloys

Three related conversion coating methods are described that are based on film formation which occurs when aluminum alloys are exposed to alkaline Li salt solutions. Representative examples of the processing methods, resulting coating structure, composition and morphology are presented. The corrosion resistance of these coatings to aerated 0.5 M NaCl solution has been evaluated as a function of total processing time using electrochemical impedance spectroscopy (EIS). This evaluation shows that excellent corrosion resistance can be uniformly achieved using no more than 20 minutes of process time for 6061-T6. Using current methods a minimum of 80 minutes of process time is required to get marginally acceptable corrosion resistance for 2024-T3. Longer processing times are required to achieve uniformly good corrosion resistance.
Date: February 1, 1996
Creator: Buchheit, R.G.
Object Type: Article
System: The UNT Digital Library
Alpha contamination assessment for D&D activities: Monitoring concrete surfaces (open access)

Alpha contamination assessment for D&D activities: Monitoring concrete surfaces

The process of decontaminating and decomissioning former nuclear facilities sometimes requires that large areas of concrete and other materials be scanned to verify they are not contaminated. A specially developed concrete surface monitor (CSM) can greatly expedite that process. The CSM is basically an aluminum box, open on the bottom, that uses an electrostatic field to transport ions created by alpha particles interacting with ambient air to a collection grid or plate. A sensitive electrometer measures the resulting current, which is essentially proportional to surface alpha activity. The initial prototype CSM surveys a surface area of some 300 cm{sup 2} at one time, while a second-generation prototype surveys 2500 cm{sup 2} and is designed to compensate automatically for radon, which can cause substantial errors in estimating surface contamination in some cases. These monitors have been successfully demonstrated on a number of concrete surfaces in situ as well as on concrete pieces cut from former facilities.
Date: February 1, 1996
Creator: Rawool-Sullivan, M.W.; Conaway, J.G. & MacArthur, D.W.
Object Type: Report
System: The UNT Digital Library
Alpha contamination assessment for D&D activities: Monitoring inside glove boxes and vessels (open access)

Alpha contamination assessment for D&D activities: Monitoring inside glove boxes and vessels

We have developed a new approach to glove box monitoring that involves drawing air out of one glove port through a detection grid that collects ions created in the air inside the glove box by ionizing radiation, especially alpha radiation. The charge deposited on the detection grid by the ions is measured with a sensitive electrometer. The air can be circulated back to the glove box through the other glove port, preventing contamination from leaving the glove box and detector system. Initial experiments using a mock-up constructed of sheet metal indicate that this technology provides the measurement technique needed to perform a defensible, non-invasive measurement of alpha contamination inside glove boxes destined for waste disposal. This can result in an enormous cost savings if a given glove box can be shown to fall into the catagory of Low-Level Waste rather than Trans-Uranic Waste. Considering that hundreds of glove boxes contaminated with plutonium will be taken out of service at various nuclear facilities over the next few years, the potential cost savings associated with disposal as LLW rather than TRU waste are substantial.
Date: February 1, 1996
Creator: Rawool-Sullivan, M. W.; Bolton, R. D.; Conaway, J. G. & MacArthur, D. W.
Object Type: Report
System: The UNT Digital Library
Alpha contamination assessment for D&D activities: Monitoring pipe interiors (open access)

Alpha contamination assessment for D&D activities: Monitoring pipe interiors

We have developed a prototype instrument capable of assessing alpha-emitting contamination on interior surfaces of ducts, pipes, tanks, and other enclosed volumes without inserting a probe. Air is drawn through the potentially contaminated volume and then through a detection grid, where ions created in the air by alpha particles are collected and the resulting charge measured with a sensitive electrometer. A filter at the intake end of the contaminated volume excludes externally created ions, so only ions generated inside the volume are detected. We have studied the response of this prototype in initial experiments using calibrated alpha sources with various pipe diameters and configurations, air flows, and source locations in the pipes. The results of these experiments indicate that this method can be an effective approach to assessing internal contamination.
Date: February 1, 1996
Creator: Rawool-Sullivan, M.W.; Conaway, J.G.; MacArthur, D.W. & Vaccarella, J.
Object Type: Report
System: The UNT Digital Library
Alpha contamination assessment for D&D activities: Technology overview (open access)

Alpha contamination assessment for D&D activities: Technology overview

Instruments based on the principle of Long-Range Alpha Detection (LRAD) detect the ions created in ambient air by Ionizing radiation, particularly alpha radiation, interacting with air molecules. Using either an electrostatic field or forced convection, these ions can be transported to a detection grid where the ions produce a small current that is measured with a sensitive electrometer. LRAD-based instruments can give separate, simultaneous measurements of alpha-emitting solids and inert radioactive gases such as radon. LRAD-based instruments assess surface contamination on an entire object or large surface area in a single, rapid measurement, including relatively inaccessible areas such as interior surfaces of pipes and process equipment. The LRAD concept is well proven and has been developed into a range of different radiation detection devices. This paper presents an overview of the technology, while several associated papers explore specific applications in greater detail.
Date: February 1, 1996
Creator: Conaway, J.G.; Rawool-Sullivan, M.W. & MacArthur, D.W.
Object Type: Report
System: The UNT Digital Library
An alternate method for prediction of the micromechanical properties of laminated composites (open access)

An alternate method for prediction of the micromechanical properties of laminated composites

The theory for an alternate method to classical laminate theory for the prediction of the macromechanical properties of laminated composite materials is developed and verified by comparing the predicted lamina stresses to those from a detailed finite element calculation. The usefulness of the method is demonstrated by comparing the load-displacement calculation using the equivalent properties to experimentally measured data from a 4-Point bending experiment.
Date: February 1, 1996
Creator: Bennett, J.; Kenamond, M. & Haberman, K.
Object Type: Article
System: The UNT Digital Library
An alternative approach to filled--via processing (open access)

An alternative approach to filled--via processing

In order to create sub micron vias between metal layers on silicon IC circuits, the tungsten filled via processes have been in a constant state of development over the past 15 years. Processing is complex, expensive, and difficult to reproduce. The introduction of galvanic cells, via undercutting, and exposed plugs are just some of the plagues that have hit several users of the technology. Discussed in this paper is an alternative approach to the complex tungsten filled via interconnect process. The proposed process yields well at sub micron geometries, is easy to perform, and is inexpensive compared to the tungsten filled via process. Contact resistance improves greatly over the standard tungsten process. The test run achieved a mean value of 0.25 ohms per via compared to historic tungsten process that yields 0.4 ohms per via. The distribution was also excellent with sigma recorded at 0.025 ohms per via.
Date: February 1, 1996
Creator: Farino, A.J.
Object Type: Article
System: The UNT Digital Library
Alternative cathodes for molten carbonate fuel cells (open access)

Alternative cathodes for molten carbonate fuel cells

Argonne National Laboratory (ANL) is developing advanced cathodes for pressurized operation of the molten carbonate fuel cell (MCFC). The present cathode, lithiated nickel oxide, tends to transport to the anode of the MCFC, where it is deposited as metallic nickel. The rate of transport increases with increasing CO{sub 2} pressure. This increase is due to an increased solubility of nickel oxide (NiO) in the molten carbonate electrolyte. An alternative cathode is lithium cobaltate (LiCoO{sub 2})-Solid solutions of LiCoO{sub 2} in LiFeO{sub 2} show promise for long-lived cathode materials. We have found that small additions of LiCoO{sub 2} to LiFeO{sub 2} markedly decrease the resistivity of the cathode material. Cells containing the LiCoO{sub 2}-LiFeO{sub 2} cathodes have stable performance for more than 2100 h of operation and display lower cobalt migration.
Date: February 1996
Creator: Bloom, I.; Lanagan, M.; Roche, M. F. & Krumpelt, M.
Object Type: Report
System: The UNT Digital Library
Alternatives to traditional transportation fuels 1994. Volume 1 (open access)

Alternatives to traditional transportation fuels 1994. Volume 1

In this report, alternative and replacement fuels are defined in accordance with the EPACT. Section 301 of the EPACT defines alternative fuels as: methanol, denatured ethanol, and other alcohols; mixtures containing 85% or more (or such other percentage, but not less than 70%, as determined by the Secretary of Energy, by rule, to provide for requirements relating to cold start, safety, or vehicle functions) by volume of methanol, denatured ethanol, and other alcohols with gasoline or other fuels; natural gas; liquefied petroleum gas; hydrogen; coal-derived liquid fuels; fuels (other than alcohol) derived from biological materials; electricity (including electricity from solar energy); and any other fuel the Secretary determines, by rule, is substantially not petroleum and would yield substantial energy security benefits and substantial environmental benefits. The EPACT defines replacement fuels as the portion of any motor fuel that is methanol, ethanol, or other alcohols, natural gas, liquefied petroleum gas, hydrogen, coal-derived liquid fuels, fuels (other than alcohol) derived from biological materials, electricity (including electricity from solar energy), ethers, or any other fuel the Secretary of Energy determines, by rule, is substantially not petroleum and would yield substantial energy security benefits and substantial environmental benefits. This report covers only those alternative …
Date: February 1, 1996
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Aminodisilanes as silylating agents for dry-developed positive-tone resists for extreme ultraviolet (13.5) microlithography (open access)

Aminodisilanes as silylating agents for dry-developed positive-tone resists for extreme ultraviolet (13.5) microlithography

We recently described a near-surface imaging scheme that employs disilanes and a bilayer resist scheme which together dramatically improve silicon contrast. A relatively thin 0.25 to 0.1 {mu}m imaging layer of a chemically amplified photo-crosslinking resist (Shipley XP-8844 or XP-9472) is spin coated on top of a thicker (0.25-0.5 {mu}m) layer of hard-baked resist (such as Shipley MP-1807). This bilayer scheme improves silicon contrast and provides additional advantages such as providing a planarizing layer and a processing layer.
Date: February 1, 1996
Creator: Wheeler, D.; Kubiak, G.; Henderson, C. & Ray-Chadhuri, A.
Object Type: Article
System: The UNT Digital Library
Amorphous silicon research. Annual subcontract report, October 1, 1994--September 30, 1995 (open access)

Amorphous silicon research. Annual subcontract report, October 1, 1994--September 30, 1995

The major effort in this program is to develop cost-effective processes which satisfy efficiency, yield, and material usage criteria for mass production of amorphous silicon-based multijunction modules. New and improved processes were developed for the component cells and a more robust rear contact was developed for better long term stability.
Date: February 1, 1996
Creator: Arya, R.R.; Bennett, M. & Bradley, D.
Object Type: Report
System: The UNT Digital Library
Analysis of a ship-to-ship collision (open access)

Analysis of a ship-to-ship collision

Sandia National Laboratories is involved in a safety assessment for the shipment of radioactive material by sea. One part of this study is investigation of the consequences of ship-to-ship collisions. This paper describes two sets of finite element analyses performed to assess the structural response of a small freighter and the loading imparted to radioactive material (RAM) packages during several postulated collision scenarios with another ship. The first series of analyses was performed to evaluate the amount of penetration of the freighter hull by a striking ship of various masses and initial velocities. Although these analyses included a representation of a single RAM package, the package was not impacted during the collision so forces on the package could not be computed. Therefore, a second series of analyses incorporating a representation of a row of seven packages was performed to ensure direct package impact by the striking ship. Average forces on a package were evaluated for several initial velocities and masses of the striking ship. In addition to. providing insight to ship and package response during a few postulated ship collisions scenarios, these analyses will be used to benchmark simpler ship collision models used in probabilistic risk assessment analyses.
Date: February 1, 1996
Creator: Porter, V.L. & Ammerman, D.J.
Object Type: Article
System: The UNT Digital Library