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Proceedings of the Workshop on Geothermal Reservoir Engineering
28
Winter Fuels Report
17
Fiscal Year 1999
11
Fiscal Year 2000
9
Journal of Undergraduate Research
9
Notes of Monthly Component Test Program Review Meeting Held with SNPO at WANL
9
OIT Best Practices
8
Saxton Plutonium Project Quarterly Progress Report
8
Distributed Energy & Electric Reliability Fact Sheets
7
Fiscal Year 2006
7
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Single Bunch Stability to Monopole Excitation
We study single bunch stability with respect to monopole longitudinal oscillations in electron storage rings. Our analysis is different from the standard approach based on the linearized Vlasov equation. Rather, we reduce the full nonlinear Fokker-Planck equation to a Schroedinger-like equation which is subsequently analyzed by perturbation theory. We show that the Haissinski solution [3] may become unstable with respect to monopole oscillations and derive a stability criterion in terms of the ring impedance. We then discuss this criterion and apply it to a broad band resonator impedance model.
Date:
January 19, 1999
Creator:
Podobedov, Boris
Object Type:
Report
System:
The UNT Digital Library
Results of design calculations. Specification of a prototype zone plate for focusing hard x-rays
A zone plate capable of focusing hard x-rays to less than 1 {mu}m spot size is designed and specified. This design is based on the state-of-art fabrication technology available today. This zone plate consists of Cu/Al layers sputtered alternatively on a round stainless steel core. Parameters of this zone plate are given. The focal length f is given for 8Kev x-rays and the thickness is optimized for focusing efficiency of the same x-ray energy.
Date:
January 1991
Creator:
Yun, W. B.; Chrzas, J. & Viccaro, P. J.
Object Type:
Report
System:
The UNT Digital Library
Chemical decomposition of high-level nuclear waste storage/disposal glasses under irradiation. 1997 annual progress report
'The objective of this research is to use the sensitive technique of electron spin resonance (ESR) to look for evidence of radiation-induced chemical decomposition of vitreous forms contemplated for immobilization of plutonium and/or high-level nuclear wastes, to interpret this evidence in terms of existing knowledge of glass structure, and to recommend certain materials for further study by other techniques, particularly electron microscopy and measurements of gas evolution by high-vacuum mass spectroscopy. Previous ESR studies had demonstrated that an effect of y rays on a simple binary potassium silicate glass was to induce superoxide (O{sub 2}{sup -}) and ozonide (O{sub 3}{sup -}) as relatively stable product of long-term irradiation Accordingly, some of the first experiments performed as a part of the present effort involved repeating this work. A glass of composition 44 K{sub 2}O: 56 SiO{sub 2} was prepared from reagent grade K{sub 2}CO3 and SiO{sub 2} powders melted in a Pt crucible in air at 1,200 C for 1.5 hr. A sample irradiated to a dose of 1 MGy (1 MGy = 10{sup 8} rad) indeed yielded the same ESR results as before. To test the notion that the complex oxygen ions detected may be harbingers of radiation-induced phase separation …
Date:
January 1, 1997
Creator:
Griscom, D.L. & Merzbacher, C.I.
Object Type:
Report
System:
The UNT Digital Library
Probing coal reactivity by time-resolved small angle x-ray scattering.
The objective of this study is to observe changes in coal structure in situ with small angle X-ray scattering (SAXS) during solvent swelling and during pyrolysis. We have built a SAXS instrument at the Basic Energy Sciences Synchrotrons Research Center at the Advanced Photon Source that allows us to obtain scattering patterns in the millisecond time domain. The eight Argonne Premium Coal samples were used in this study. The information that can be derived from these experiments, such as changes in fractal dimensionality and in size and type of porosity, was found to be very rank-dependent. In the swelling experiments, it was noted that for certain coals, structural changes occurred in just a few minutes.
Date:
January 22, 1999
Creator:
Winans, R. E.
Object Type:
Article
System:
The UNT Digital Library
Report on the international workshop on cold moderators for pulsed neutron sources.
The International Workshop on Cold Moderators for Pulsed Neutron Sources resulted from the coincidence of two forces. Our sponsors in the Materials Sciences Branch of DOE's Office of Energy Research and the community of moderator and neutron facility developers both realized that it was time. The Neutron Sources Working Group of the Megascience Forum of the Organization for Economic Cooperation and Development offered to contribute its support by publishing the proceedings, which with DOE and Argonne sponsorship cemented the initiative. The purposes of the workshop were: to recall and improve the theoretical groundwork of time-dependent neutron thermalization; to pose and examine the needs for and benefits of cold moderators for neutron scattering and other applications of pulsed neutron sources; to summarize experience with pulsed source, cold moderators, their performance, effectiveness, successes, problems and solutions, and the needs for operational data; to compile and evaluate new ideas for cold moderator materials and geometries; to review methods of measuring and characterizing pulsed source cold moderator performance; to appraise methods of calculating needed source characteristics and to evaluate the needs and prospects for improvements; to assess the state of knowledge of data needed for calculating the neutronic and engineering performance of cold moderators; …
Date:
January 6, 1999
Creator:
Carpenter, J. M.
Object Type:
Article
System:
The UNT Digital Library
Two implementations of shared virtual space environments.
While many issues in the area of virtual reality (VR) research have been addressed in recent years, the constant leaps forward in technology continue to push the field forward. VR research no longer is focused only on computer graphics, but instead has become even more interdisciplinary, combining the fields of networking, distributed computing, and even artificial intelligence. In this article we discuss some of the issues associated with distributed, collaborative virtual reality, as well as lessons learned during the development of two distributed virtual reality applications.
Date:
January 13, 1998
Creator:
Disz, T. L.
Object Type:
Article
System:
The UNT Digital Library
Ordering in classical Coulombic systems.
The author discusses the properties of classical Coulombic matter at low temperatures. It has been well known for some time [1,2] that infinite Coulombic matter will crystallize in body-centered cubic form when the quantity {Lambda} (the dimensionless ratio of the average two-particle Coulomb energy to the kinetic energy per particle) is larger than {approximately}175. But the systems of such particles that have been produced in the laboratory in ion traps, or ion beams, are finite with surfaces defined by the boundary conditions that have to be satisfied. This results in ion clouds with sharply defined curved surfaces, and interior structures that show up as a set of concentric layers that are parallel to the outer surface. The ordering does not appear to be cubic, but the charges on each shell exhibit a ''hexatic'' pattern of equilateral triangles that is the characteristic of liquid crystals. The curvature of the surfaces prevents the structures on successive shells from interlocking in any simple fashion. This class of structures was first found in simulations [3] and later in experiments [4].
Date:
January 22, 1998
Creator:
Schiffer, J. P.
Object Type:
Article
System:
The UNT Digital Library
Modeling the post-yield flow behavior after neutron and electron irradiation of steels and iron-base alloys.
Irradiation hardening is an issue of practical importance as it relates to the remanent life and the nature of failure of reactor components exposed to displacement-producing radiation. For example, irradiation-induced yield strength increases in pressure vessel steels are directly related to increases in the ductile-to-brittle-transition-temperature of these materials. Other issues associated with hardening, such as reductions in ductility, toughness and fatigue life of structural steels are also of concern. Understanding these phenomena requires studies of fundamental microstructural mechanisms of hardening. Because of the limited supply of neutron-irradiated surveillance material, difficulties posed by the radioactivity of neutron-exposed samples and the uncertainty of irradiation conditions in this case, fundamental studies are often conducted using well-controlled experiments involving irradiation by electrons instead of neutrons. Also, in such studies, simple model alloys are used in place of steels to focus on the influence of specific alloy constituents. It is, therefore, important to understand the relationship between the results of this kind of experiment and the effects of in-reactor neutron exposure in order to use them to make predictions of significance to reactor component life. In this paper, we analyze the tensile behavior of pressure vessel steels (A212B and A350) irradiated by neutrons and electrons. …
Date:
January 13, 1999
Creator:
Dimelfi, R. J.
Object Type:
Article
System:
The UNT Digital Library
Decontamination of metals by melt refining/slagging. An annotated bibliography: Update on stainless steel and steel
The following presentation is an update to a previous annotation, i.e., WINCO-1138. The literature search and annotated review covers all metals used in the nuclear industries but the emphasis of this update is directed toward work performed on mild steels. As the number of nuclear installations undergoing decontamination and decommissioning (D&D) increases, current radioactive waste storage space is consumed and establishment of new waste storage areas becomes increasingly difficult, the problem of handling and storing radioactive scrap metal (RSM) gains increasing importance in the DOE Environmental Restoration and Waste Management Program. To alleviate present and future waste problems, Lockheed Idaho Technologies Co (LITCO) is managing a program for the recycling of RSM for beneficial use within the DOE complex. As part of that effort, Montana Tech has been awarded a contract to help optimize melting and refining technology for the recycling of stainless steel RSM. The scope of the Montana Tech program includes a literature survey, a decontaminating slag design study, small wide melting studies to determine optimum slag compositions for removal of radioactive contaminant surrogates, analysis of preferred melting techniques, and coordination of large scale melting demonstrations (100--2,000 lbs) to be conducted at selected facilities. The program will support …
Date:
January 1, 1995
Creator:
Worchester, S. A.; Twidwell, L. G.; Paolini, D. J.; Weldon, T. A. & Mizia, R. E.
Object Type:
Report
System:
The UNT Digital Library
Strontium isotopes in carbonate deposits at Crater Flat, Nevada
Strontium isotope studies of carbonates from soils, veins, eolian dust and Paleozoic basement samples near Crater Flat, southwest of Yucca Mountain, provide evidence for the origins of these materials. Vein and soil carbonates have nearly identical ranges of {sup 87}Sr/{sup 86}Sr ratios at the lower end of the pedogenic range. The average {sup 87}Sr/{sup 86}Sr of Paleozoic basement from Black Marble Hill is similar to the {sup 87}Sr/{sup 86}Sr in the eolian dust, perhaps indicating a local source for this material. Possible spring deposits have generally higher {sup 87}Sr/{sup 86}Sr than the other carbonates. These data are compared with similar data from areas east of Yucca Mountain. 7 refs., 5 figs.
Date:
January 1, 1991
Creator:
Marshall, B.D.; Futa, K.; Peterman, Z.E. & Stuckless, J.S.
Object Type:
Article
System:
The UNT Digital Library
RCRA Post Closure Monitoring and Inspection Report for CAU 91: Area 3 U-3fi Waste Unit, Nevada Test Site for the Period October 1996-1997
This annual Neutron Soil Moisture Monitoring report provides an analysis and summary for site inspections, meteorological information, and neutron soil moisture monitoring data obtained at the U-3fi Resource Conservation and Recovery Act (RCRA) Unit, located in Area 3 of the Nevada Site (NTS), Nye County, Nevada, during the October 1996-October 1997 period. Inspections of the U-3fi RCRA Unit are conducted to determine and document the physical condition of the concrete pad, facilities, and any unusual conditions that could impact the proper operation of the waste unit closure. The objective of the neutron logging is to monitor the soil moisture conditions along the 128 meter (420 feet) ER3-3 monitoring well and detect changes that may be indicative of moisture movement in the regulated interval extending between 73 m to 82 m (240 to 270 ft).
Date:
January 1, 1998
Creator:
Emer, Dudley
Object Type:
Report
System:
The UNT Digital Library
Comparative nuclear effects of biomedical interest. Civil effects study
Selected physical and biological data bearing upon the environmental variations created by nuclear explosions are presented in simplified form. Emphasis is placed upon the ``early`` consequences of exposure to blast, thermal radiation, and ionizing radiation to elucidate the comparative ranges of the major effects as they vary with explosive yield and as they contribute to the total hazard to man. A section containing brief definitions of the terminology employed is followed by a section that utilizes text and tabular material to set forth events that follow nuclear explosions and the varied responses of exposed physical and biological materials. Finally, selected quantitative weapons-effects data in graphic and tabular form are presented over a wide range of explosive yields to show the relative distances from Ground Zero affected by significant levels of blast overpressures, thermal fluxes, and initial and residual penetrating ionizing radiations. However, only the ``early`` rather than the ``late`` effects of the latter are considered.
Date:
January 12, 1961
Creator:
White, C.S.; Bowen, I.G.; Richmond, D.R. & Corsbie, R.L.
Object Type:
Report
System:
The UNT Digital Library
A preliminary guidebook for identifying stratigraphic contacts at the Nevada Test Site
Lithologic variation, regional depositional trends, and the lack of written guidelines have resulted in inconsistencies in the recognition of stratigraphic contacts in drill holes at the Nevada Test Site (NTS). Stratigraphic identification, based on mineralogy of discrete samples, can be augmented by geophysical logs and downhole movies to more accurately and consistently locate contacts between units. Criteria are established for locating the base of the Pahute Mesa ash-flow tuff, the top of the Ammonia Tanks ash-flow tuff, the top of the Ammonia Tanks bedded tuff, and the top and the base of the Rainier Mesa Tuff.
Date:
January 1, 1992
Creator:
Pawloski, G. A.; McKague, H. L.; Wagoner, J. L. & McKinnis, W.B.
Object Type:
Article
System:
The UNT Digital Library
Streamflow and selected precipitation data for Yucca Mountain and vicinity, Nye County, Nevada, water years 1983--85
Streamflow and precipitation data collected at and near Yucca Mountain, Nevada, during water years 1983--85, are presented in this report. The data were collected and compiled as part of the studies the US Geological Survey is making, in cooperation with the US Department of Energy, to characterize surface-water hydrology in the Yucca Mountain area. Streamflow data include daily mean discharges and peak discharges at 4 complete-record gaging stations and peak discharges at 10 crest-stage, partial-record stations and 12 miscellaneous sites. Precipitation data include cumulative totals at 12 stations maintained by the US Geological Survey and daily totals at 17 stations maintained by the Weather Service Nuclear Support Office, National Oceanic and Atmospheric Administration.
Date:
January 1, 1993
Creator:
Pabst, M. E.; Beck, D. A.; Glancy, P. A. & Johnson, J. A.
Object Type:
Report
System:
The UNT Digital Library
Characterizing the altered zone at Yucca Mountain: The beginning of a testing strategy
The concept of a disturbed zone surrounding the mined openings of a potential geologic repository for high-level radioactive waste was introduced by the US Nuclear Regulatory Commission (NRC) as a region to be excluded for determining groundwater travel time to the accessible environment, but to be included for determining the impact of underground construction and radioactive decay heat on groundwater movement and radionuclide transport for total system performance analysis. This paper explores both the regulatory and technical necessity for characterizing and modeling a larger region -- the altered zone -- within which the temperature is increased significantly by heat from the high-level waste. Particular attention is given to addressing the effects of heterogeneity on groundwater flux and travel time, showing how these effects might be modeled simply on a macroscopic scale, and outlining its parameters. The effect of uncertainty in the parameter values on the performance of a potential repository can then be easily handled by probabilistic analysis.
Date:
January 8, 1992
Creator:
Chesnut, D.A.
Object Type:
Article
System:
The UNT Digital Library
The effect of neutrals on the global heliosphere and interplanetary shock propagation time to the heliopause
A two-dimensional time-dependent two-fluid hydrodynamic model has been used to study numerically the effect of interstellar neutrals on the size and structure of the heliosphere. The interstellar neutrals, coupled to the plasma by charge-exchange collisions, lead to a dramatic decrease in the size of the heliosphere -- 30% for the parameters studied. We find that a build up of neutral hydrogen in front of the leading edge of the heliospbere, seen in earlier models, occurs only when the flow in the interstellar medium is supersonic. When the flow is subsonic, no such hydrogen ``wall`` is seen in the simulations, suggesting that the distribution of scattered solar H Ly a light may be quite different for this case. We have also calculated the propagation of an interplanetary shock to the heliopause as a possible trigger for the 1992 Voyager 2--3 kHz radio emission event. We find that the interstellar plasma density, observed emission cut-off frequency, and heliopause location can all b made consistent once the effect of the reduction in the size of the heliosphere by the interaction with the neutrals is included.
Date:
January 1, 1995
Creator:
Liewer, P. C.; Karmesin, S. R. & Brackbill, J. U.
Object Type:
Article
System:
The UNT Digital Library
Hanford Environmental Information System (HEIS); Volume 8, Tank Characterization Data (TCD) subject area
The purpose of the Tank Characterization Data subject area of the Hanford Environmental Information System (HEIS) is to manage data acquired from waste tank characterization efforts. Tank samples provide the data stored in this subject area. Also included are data from tank inventories. These data are analyzed to determine disposal requirements, such as suitability for grout or vitrification. The data provide the basis for developing safety analyses and closure plans, and for establishing and verifying compliance with waste acceptance specifications. Two major sources of data make up the tank characterization data subject area: Data from single-shell and double-shell tank core samples -- core sampling analytical results include physical properties, radionuclides, major chemicals, and hazardous components; and data from waste tank supernatant samples. Four types of data are stored in the TCD subject area. Qualifiers for TCD analytical result data are listed in Appendix A. Data loading and verification procedures are described in Appendix B.
Date:
January 14, 1994
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Sonic decontamination
The supersonic method of cleaning glassware is an outgrowth of the fact that it has been heretofore impossible to manually clean ground glass and quartz joints because the activity became lodged in the small pores of the ground surfaces. It has been theorized that the nature of the forces binding polonium to the glass is similar to that of the chemical bond but are less intense. The problem then becomes one of finding a force greater than this binding energy, capable of freeing the activity from the glass. This has been accomplished by using frequencies of 100 cycles to 20 kc at a power output from 2 to 20 watts, passing through a citric acid solution (pH-2) into which the contaminated article is placed. The optimum results, using a tank with the dimensions 7 in. {times} 7 in. {times} 7 in. and 3 liters of solution, has been found at 200 cycles or harmonics of 200 cycles. Citric acid was used because of the fact that it forms a soluble complex with polonium. The frequencies used have been kept within the sonic range until enough data has been obtained and correlated to warrant the design and construction of more costly …
Date:
January 25, 1949
Creator:
Brodbeck, R. M. & Schommer, G. R.
Object Type:
Report
System:
The UNT Digital Library
The U.S. RERTR program status and progress.
The progress of the Reduced Enrichment Research and Test Reactor (RERTR) Program since its inception in 1978 is described. A brief summary of the results which the RERTR Program had achieved by the end of 1996 in collaboration with its many international partners is followed by a detailed review of the major events, findings, and activities of 1997. Significant progress has been made during the past year. In the area of U.S. acceptance of spent fuel from foreign research reactors, several shipments have taken place and additional are being planned. Intense fuel development activities are in progress, including procurement of equipment, screening of candidate materials, and production of microplates. Irradiation of the first series of microplates began in August 1997 in the Advanced Test Reactor, in Idaho. Progress has been made in the Russian RERTR program, which aims to develop and demonstrate within five years the technical means needed to convert Russian-supplied research reactors to LEU fuels. The study of an alternative LEU core for the FRM-II design has been extended to address, with favorable results, controversial performance issues which were raised at last year's meeting. Progress was also made on several aspects of producing molybdenum-99 from fission targets utilizing …
Date:
January 21, 1998
Creator:
Travelli, A.
Object Type:
Article
System:
The UNT Digital Library
Electromechanical properties of superconductors for DOE fusion applications
The electrical performance of many superconducting materials is strongly dependent on mechanical load. This report presents electromechanical data on a broad range of high-magnetic-field superconductors. The conductors that were studied fall into three general categories: Candidate conductors, experimental conductors, and reference conductors. Research on candidate conductors for fusion applications provides screening data for superconductor selection as well as engineering data for magnet design and performance analysis. The effect of axial tensile strain on critical-current density was measured for several Nb{sub 3}Sn candidate conductors including the US-DPC (United States Demonstration Poloidal Coil) cable strand and an ITER (International Thermonuclear Experimental Reactor) candidate conductor. Also, data are presented on promising experimental superconductors that have strong potential for fusion applications. Axial strain measurements were made on a V{sub 3}Ga tape conductor that has good performance at magnetic fields up to 20 T. Axial strain data are also presented for three experimental Nb{sub 3}Sn conductors that contain dispersion hardened copper reinforcement for increased tensile strength. Finally, electromechanical characteristics were measured for three different Nb{sub 3}Sn reference conductors from the first and second VAMAS (Versailles Project on Advanced Materials and Standards) international Nb{sub 3}Sn critical-current round robins. Published papers containing key results, including the first …
Date:
January 1994
Creator:
Ekin, J. W.; Bray, S. L.; Lutgen, C. L. & Bahn, W. L.
Object Type:
Report
System:
The UNT Digital Library
Proceedings of the Nuclear Criticality Technology and Safety Project Workshop
This report is the proceedings of the annual Nuclear Criticality Technology and Safety Project (NCTSP) Workshop held in Monterey, California, on April 16--28, 1993. The NCTSP was sponsored by the Department of Energy and organized by the Los Alamos Critical Experiments Facility. The report is divided into six sections reflecting the sessions outlined on the workshop agenda.
Date:
January 1, 1994
Creator:
Sanchez, R.G.
Object Type:
Article
System:
The UNT Digital Library
Revision of ASCE 4
The original version of ASCE Standard 4, ``Seismic Analysis of Safety-Related Nuclear Structures`` was published in September 1986. It is ASCE policy to update its standards on a five year interval and the Working Group on Seismic Analysis of Safety Related Nuclear Structures was reconvened to formulate the revisions. The goal in updating the standard is to make sure that it is still relevant and that it incorporates the state of the practice in seismic engineering or, in some cases, where it has been demonstrated that state-of-the-art improvements need to be made to standard practice; new improvements are included. The contents of the new standard cover the same areas as the original version, with some additions. The contents are as follows: Input - response spectra and time histories; modeling of structures; analysis of structures; soil-structure interaction; input for subsystem analysis; special structures - buried pipes and conduits, earth-retaining walls, above-ground vertical tanks, raceways, and base-isolated structures; and an appendix providing seismic probabilistic risk assessment and margin assessment.
Date:
January 24, 1995
Creator:
Nelson, T. A.; Murray, R. C. & Short, S. A.
Object Type:
Article
System:
The UNT Digital Library
Single fracture aperture patterns: Characterization by slit-island fractal analysis
Single fracture measurements are difficult to obtain, but they are the only means we have to observe and study natural fracture morphology. The character of the fracture openings (apertures) is often one of the primary factors controlling fluid flow in the fracture. In particular, the shape, distribution, and connectivity of contact areas and flow channels can affect the relative permeability of wetting and non-wetting fluid phases in unsaturated systems. In this paper we use three methods of fractal analysis (the slit-island, the divider, and the variogram) as well as statistical and geostatistical analysis to characterize the geometry of measured fracture apertures obtained from two different fractured rock specimens from the field. One of these is a granitic fracture (crack) of homogeneous lithology and no displacement, the other is a fracture (fault) obtained from a highly altered fault zone, containing striations and slickensides. We discuss the fractal and geostatistical analysis of these two fractures in the context of what information is most helpful for making predictions about fluid flow in single fractures.
Date:
January 1, 1993
Creator:
Cox, B.L. & Wang, J.S.Y.
Object Type:
Article
System:
The UNT Digital Library
Using ytterbium-169 for safe and economical industrial radiography
Safety has become an issue of paramount importance for industrial radiography. Many NDE facilities and suppliers are finding the cost of performing radiography Prohibitive due to heightened safety concerns for radiation area protection. The most common sources used in radiography, Iridium-192 and Cobalt-60, result in high radiation fields over a large area. Even when collimators are used large radiation fields can result from multicurie source radiography. Radiographic operations are being forced to find alternative test methods and techniques to the use of the old stand-by sources. These alternate methods are not always as comprehensive a test as full volumetric examination with radiography. Since Iridium and Cobalt are in such wide spread use, they are sometimes called upon to perform test of materials which are not in their optimum sensitivity range.
Date:
January 1, 1994
Creator:
Dowalo, J.A.
Object Type:
Report
System:
The UNT Digital Library