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Identification of mine collapses, explosions and earthquakes using INSAR: a preliminary investigation

Description: Interferograms constmcted from satellite-borne synthetic aperture radar images have the capability of mapping sub-cm ground surface deformation over areas on the order of 100 x 100 km with a spatial resolution on the order of 10 meters. We investigate the utility of synthetic aperture radar interferomehy (InSAR) used in conjunction with regional seismic methods in detecting and discriminating different types of seismic events in the context of special event analysis for the CTBT. For this initial study, we carried out elastic dislocation modeling of underground explosions, mine collapses and small (M<5.5) shallow earthquakes to produce synthetic interferograms and then analyzed satellite radar data for a large mine collapse. The synthetic modeling shows that, for a given magnitude each type of event produces a distinctive pattern of ground deformation that can be recognized in, and recovered from, the corresponding interferogram. These diagnostic characteristics include not only differences in the polarities of surface displacements but also differences in displacement amplitudes from the different sources. The technique is especially sensitive to source depth, a parameter that is crucial in discriminating earthquakes from the other event types but is often very poorly constrained by regional seismic data alone. The ERS radar data analyzed is from a M<sub>L</sub> 5.2 seismic event that occurred in southwestern Wyoming on February 3,1995. Although seismic data from the event have some characteristics of an underground explosion, based on seismological and geodetic data it has been identified as being caused by a large underground collapse in the Solvay Mine. Several pairs of before-collapse and after-collapse radar images were phase processed to obtain interferograms. The minimum time separation for a before-collapse and after-collapse pair was 548 days. Even with this long time separation, phase coherence between the image pairs was acceptable and a deformation map was successfully obtained. Two images, separated ...
Date: July 7, 1998
Creator: Foxall, B; Sweeney, J J & Walter, W R
Partner: UNT Libraries Government Documents Department

Engineering study for closure of 209E facility

Description: This document is an engineering study for evaluating alternatives to determine the most cost effective closure plan for the 209E Facility, Critical Mass Laboratory. This laboratory is located in the 200 East Area of the Hanford Site and contains a Critical Assembly Room and a Mix room were criticality experiments were once performed.
Date: July 7, 1997
Creator: Brevick, C.H.; Heys, W.H. & Johnson, E.D.
Partner: UNT Libraries Government Documents Department

Test plan for immobilization of salt-containing surrogate mixed wastes using polyester resins

Description: Past operations at many Department of Energy (DOE) sites have resulted in the generation of several waste streams with high salt content. These wastes contain listed and characteristic hazardous constituents and are radioactive. The salts contained in the wastes are primarily chloride, sulfate, nitrate, metal oxides, and hydroxides. DOE has placed these types of wastes under the purview of the Mixed Waste Focus Area (MWFA). The MWFA has been tasked with developing and facilitating the implementation of technologies to treat these wastes in support of customer needs and requirements. The MWFA has developed a Technology Development Requirements Document (TDRD), which specifies performance requirements for technology owners and developers to use as a framework in developing effective waste treatment solutions. This project will demonstrate the use of polyester resins in encapsulating and solidifying DOE`s mixed wastes containing salts, as an alternative to conventional and other emerging immobilization technologies.
Date: July 7, 1997
Creator: Biyani, R.K.; Douglas, J.C. & Hendrickson, D.W.
Partner: UNT Libraries Government Documents Department

Biological determinants of photobioreactor design. 6. quarterly report, February 1--July 31, 1995

Description: Interest has developed in using algae to fix CO{sub 2} to produce oxygen and biomass for life-support in space, and for reducing CO{sub 2} emissions from power plants. A novel photobioreactor (PBR) system using light-emitting diodes (LEDs) as a sole light source was constructed and operated with continuous medium perfusion. Direct internal illumination by 680 nm LEDs could deliver as high as 50 mW/cm{sup 2} of light into the culture medium. Gas transfer by internal sparging had the capacity to transfer 250 mmol O{sub 2}/L culture/h. Nutritional limitations could be overcome by continuous perfusion, supplying the medium components to the culture without increasing osmolarity, while removing potentially inhibitory cellular wastes. When the PBR operated in a continuous perfusion mode with a perfusion rate of 6 reactor volumes a day (6 VVD), it could support ultra high-density algal cultures up to cell concentrations of 4 {times} 10{sup 9} cells/mL and total cell volume fractions of 9.4% v/v (about 25 g dry weight/L). The oxygen production rate at its peak was 13 to 15 mmol/L culture/h. This performance represents the highest reported cell densities attained in photoautotrophic cultures. Continuous perfusion allowed for long-term stable oxygen production, while oxygen production in batch mode ceased when stationary phase was reached. The results presented suggest that PBR technology can still be significantly improved.
Date: July 7, 1995
Creator: Palsson, B.O. & Brown, G.G.
Partner: UNT Libraries Government Documents Department

Tank 241-TX-104, cores 230 and 231 analytical results for the final report

Description: This document is the analytical laboratory report for tank 241-TX-104 push mode core segments collected between February 18, 1998 and February 23, 1998. The segments were subsampled and analyzed in accordance with the Tank 241-TX-104 Push Mode Core Sampling and Analysis Plan (TSAP) (McCain, 1997), the Data Quality Objective to Support Resolution of the Organic Complexant Safety Issue (Organic DQO) (Turner, et al., 1995) and the Safety Screening Data Quality Objective (DQO) (Dukelow, et.al., 1995). The analytical results are included in the data summary table. None of the samples submitted for Differential Scanning Calorimetry (DSC) and Total Alpha Activity (AT) exceeded notification limits as stated in the TSAP. The statistical results of the 95% confidence interval on the mean calculations are provided by the Tank Waste Remediation Systems Technical Basis Group in accordance with the Memorandum of Understanding (Schreiber, 1997) and are not considered in this report. Appearance and Sample Handling Attachment 1 is a cross reference to relate the tank farm identification numbers to the 222-S Laboratory LabCore/LIMS sample numbers. The subsamples generated in the laboratory for analyses are identified in these diagrams with their sources shown. Core 230: Three push mode core segments were removed from tank 241-TX-104 riser 9A on February 18, 1998. Segments were received by the 222-S Laboratory on February 19, 1998. Two segments were expected for this core. However, due to poor sample recovery, an additional segment was taken and identified as 2A. Core 231: Four push mode core segments were removed from tank 241-TX-104 riser 13A between February 19, 1998 and February 23, 1998. Segments were received by the 222-S Laboratory on February 24, 1998. Two segments were expected for this core. However, due to poor sample recovery, additional segments were taken and identified as 2A and 2B. The TSAP states the core ...
Date: July 7, 1998
Creator: Diaz, L.A.
Partner: UNT Libraries Government Documents Department

Vitrification of Simulated Fernald K-65 Silo Waste at Low Temperature

Description: Vitrification is the technology that has been chosen to solidify approximately 18,000 tons of geologic mill tailings, designated as K-65 wastes, at the Fernald Environmental Management Project (FEMP) in Fernald, Ohio. The glass formula developed in this study for the FEMP wastes is a lithia substituted soda-lime-lithia-silica (SLLS) composition which melts at 1050 degrees Celsius. Low melting formulations minimize volatilization of hazardous species such as arsenic, selenium, chromium, and lead during vitrification. Formulation in the SLLS system avoids problematic phase separation known to occur in the MO-B2O3-SiO2 glass forming system (where MO = CaO, MgO, BaO, and PbO which are all constituents of the FEMP wastes). The SLLS glass passed the Environmental Protection Agency (EPA) Toxic Characteristic Leach Procedure (TCLP) for all the hazardous constituents of concern under the current regulations. The SLLS glass is as durable as the high melting soda-lime-silica glasses and is more durable than the borosilicate glasses previously developed for the K-65 wastes. Optimization of glass formulations in the SLLS glass forming system should provide glasses which will pass the newly promulgated Universal Treatment Standards which take effect of August 28, 1998.
Date: July 7, 1998
Creator: Jantzen, C.M. & Pickett, J.B.
Partner: UNT Libraries Government Documents Department

A New User-Friendly Model to Reduce Cost for Headwater Benefits Assessment

Description: Headwater benefits at a downstream hydropower project are energy gains that are derived from the installation of upstream reservoirs. The Federal Energy Regulatory Commission is required by law to assess charges of such energy gains to downstream owners of non-federal hydropower projects. The high costs of determining headwater benefits prohibit the use of a complicated model in basins where the magnitude of the benefits is expected to be small. This paper presents a new user-friendly computer model, EFDAM (Enhanced Flow Duration Analysis Method), that not only improves the accuracy of the standard flow duration method but also reduces costs for determining headwater benefits. The EFDAM model includes a MS Windows-based interface module to provide tools for automating input data file preparation, linking and executing of a generic program, editing/viewing of input/output files, and application guidance. The EDFAM was applied to various river basins. An example was given to illustrate the main features of EFDAM application for creating input files and assessing headwater benefits at the Tulloch Hydropower Plant on the Stanislaus River Basin, California.
Date: July 7, 1999
Creator: Bao, Y.S.; Cover, C.K.; Perlack, R.D.; Sale, M.J. & Sarma, V.
Partner: UNT Libraries Government Documents Department

Depleted uranium oxides as spent-nuclear-fuel waste-package invert and backfill materials

Description: A new technology has been proposed in which depleted uranium, in the form of oxides or silicates, is placed around the outside of the spent nuclear fuel waste packages in the geological repository. This concept may (1) reduce the potential for repository nuclear criticality events and (2) reduce long-term release of radionuclides from the repository. As a new concept, there are significant uncertainties.
Date: July 7, 1997
Creator: Forsberg, C.W. & Haire, M.J.
Partner: UNT Libraries Government Documents Department

Pressure dependence of the bandgap energy and the conduction-band mass for an n-type InGaAs/GaAs strained single-quantum-well

Description: We report the measurement of the pressure dependence for the bandgap energy E{sub g} and conduction-band mass m{sub c} for an 80{angstrom}-wide n-type In{sub 0.20}Ga{sub 0.80}As/GaAs single strained quantum well at 4.2K for pressures between 0 and 35 kbar and fields up to 30 tesla.
Date: July 7, 1997
Creator: Jones, E.D.; Tozer, S.T. & Schmiedel, T.
Partner: UNT Libraries Government Documents Department

Depleted uranium oxides as spent-nuclear-fuel waste-package fill materials

Description: Depleted uranium dioxide fill inside the waste package creates the potential for significant improvements in package performance based on uranium geochemistry, reduces the potential for criticality in a repository, and consumes DU inventory. As a new concept, significant uncertainties exist: fill properties, impacts on package design, post- closure performance.
Date: July 7, 1997
Creator: Forsberg, C.W.
Partner: UNT Libraries Government Documents Department

Advanced biochemical processes for geothermal brines: Current developments

Description: A research program at Brookhaven National Laboratory (BNL) which deals with the development and application of processes for the treatment of geothermal brines and sludges has led to the identification and design of cost-efficient and environmentally friendly treatment methodology. Initially the primary goal of the processing was to convert geothermal wastes into disposable materials whose chemical composition would satisfy environmental regulations. An expansion of the r and D effort identified a combination of biochemical and chemical processes which became the basis for the development of a technology for the treatment of geothermal brines and sludges. The new technology satisfies environmental regulatory requirements and concurrently converts the geothermal brines and sludges into commercially promising products. Because the chemical composition of geothermal wastes depends on the type of the resource, the emerging technology has to be flexible so that it can be readily modified to suit the needs of a particular type of resource. Recent conceptional designs for the processing of hypersaline and low salinity brines and sludges will be discussed.
Date: July 7, 1997
Creator: Premuzic, E.T.; Lin, M.S.; Bohenek, M.; Bajsarowicz, V. & McCloud, M.
Partner: UNT Libraries Government Documents Department

Time-specific measurements of energy deposition from radiation fields in simulated sub-micron tissue volumes

Description: A tissue-equivalent spherical proportional counter is used with a modified amplifier system to measure specific energy deposited from a uniform radiation field for short periods of time ({approximately}1 {micro}s to seconds) in order to extrapolate to dose in sub-micron tissue volumes. The energy deposited during these time intervals is compared to biological repair processes occurring within the same intervals after the initial energy deposition. The signal is integrated over a variable collection time which is adjusted with a square-wave pulse. Charge from particle passages is collected on the anode during the period in which the integrator is triggered, and the signal decays quickly to zero after the integrator feedback switch resets; the process repeats for every triggering pulse. Measurements of energy deposited from x rays, {sup 137}Cs gamma rays, and electrons from a {sup 90}Sr/{sup 90}Y source for various time intervals are taken. Spectral characteristics as a function of charge collection time are observed and frequency plots of specific energy and collection time-interval are presented. In addition, a threshold energy flux is selected for each radiation type at which the formation of radicals (based on current measurements) in mammalian cells equals the rate at which radicals are repaired.
Date: July 7, 1997
Creator: Famiano, M.A.
Partner: UNT Libraries Government Documents Department

Char crystalline transformations during coal combustion and their implications for carbon burnout

Description: Residual, or unburned carbon in fly ash affects many aspects of power plant performance and economy including boiler efficiency, electrostatic precipitator operation, and ash as a salable byproduct. There is a large concern in industry on the unburned carbon problem due to a variety of factors, including low-NOx combustion system and internationalization of the coal market. In recent work, it has been found that residual carbon extracted from fly ash is much less reactive than the laboratory chars on which the current kinetics are based. It has been suggested that thermal deactivation at the peak temperature in combustion is a likely phenomenon and that the structural ordering is one key mechanism. The general phenomenon of carbon thermal annealing is well known, but there is a critical need for more data on the temperature and time scale of interest to combustion. In addition, high resolution transmission electron microscopy (HRTEM) fringe imaging, which provides a wealth of information on the nature and degree of crystallinity in carbon materials such as coal chars, has become available. Motivated by these new developments, this University Coal Research project has been initiated with the following goals: (1) To determine transient, high-temperature, thermal deactivation kinetics as a function of parent coal and temperature history. (2) To characterize the effect of the thermal treatment on carbon crystalline structure through high-resolution transmission electron microscopy and specialized, quantitative image analysis.
Date: July 7, 1999
Creator: Hurt, R.H.
Partner: UNT Libraries Government Documents Department

Advanced reservoir characterization and evaluation of CO{sub 2} gravity drainage in the naturally fractured Spraberry Trend Area. Quarterly technical report

Description: The overall goal of this project is to assess the economic feasibility of CO{sub 2} flooding the naturally fractured Spraberry Trend Area in West Texas. This objective is being accomplished by conducting research in four areas: (1) extensive characterization of the reservoirs, (2) experimental studies of crude oil/brine/rock (COBR) interaction in the reservoirs, (3) analytical and numerical simulation of Spraberry reservoirs, and, (4) experimental investigations on CO{sub 2} gravity drainage in Spraberry whole cores. This report provides results of the fourth quarter of 1997 in the fourth area.
Date: July 7, 1998
Creator: Schechter, David S.
Partner: UNT Libraries Government Documents Department

Extreme Ultraviolet Lithography for 0.1 {micro}m Devices

Description: Extreme Ultraviolet Lithography (EUVL) has emerged as one of the leading successors to optics for 0.1 {micro}m IC fabrication. Its strongest attribute is the potential to scale to much finer resolution at high throughput. As such, this technique could meet the lithography needs for Si ULSI down to fundamental device limits. In the US, Lawrence Livermore, Sandia, and Lawrence Berkeley National Laboratories are participating in an industry funded research effort to evolve EUV technology and build a prototype camera for lithographic exposure. More recently, both Europe and Japan have initiated government/industry sponsored programs in EUVL development. This talk will focus on our program successes to date, and highlight some of the challenges that still lie ahead.
Date: July 7, 1999
Creator: Vaidya, S.; Sweeney, D.W.; Stulen, R. & Attwood, D.
Partner: UNT Libraries Government Documents Department

Radioactive effluents in Savannah River. Summary report for 1997

Description: The Nonproliferation Technology Section (NTS), formerly Environmental Technology Section (ETS), has conducted radiometric studies of Plant Vogtle since late 1986, seven months prior to its startup. This program has now been terminated as of May of this year, as support funding is no longer available, The present report presents the final 1997 measurements, as a closeout of this program of study, Plant Vogtle has two 1100 MWe pressurized water reactors developed by Westinghouse. Unit 1 started commercial operations in June 1987, and Unit 2 began in May 1989, During powered operations, NTS routinely detected neutron-activated isotopes in controlled releases but all activities had been orders of magnitude below the DOE guide values and EPA/CFR levels. The Vogtle release data and the NTS measurements have tracked well over the past ten years. These very sensitive ultra low-level measurements of the radioactive effluents have been important to both institutions, as they could address abnormal trends before they became health and compliance concerns.
Date: July 7, 1997
Creator: Winn, W.G.
Partner: UNT Libraries Government Documents Department

NuDat system for access to nuclear data

Description: The NuDat program provides a user with access to nuclear properties and to some nuclear reaction data. The program operates on DEC VMS operating systems and on PC`s with Microsoft operating systems. The program has four user interfaces, all having the same content and functionality. These interfaces are Web, Video and Sequential for VMS. The PC interface is identical to the VMS Video interface. Forms are used to supply the type of data the user desires, the retrieval parameters, the output format, and the sort order of the data. The program and associated database is used in basic research, particularly for the systematic study of nuclear properties. It is also a useful tool for applied research to identify radiations from radionuclides contained in environmental samples, or from those produced by neutron or charged particle activation. The NuDat database is derived from several databases maintained by the National Nuclear Data Center. The databases are the Adopted Levels and Gammas data sets from ENSDF, the Nuclear Wallet Cards, Decay Radiations derived from ENSDF decay data sets processed by RADLIST, and Thermal Neutron Cross Sections.
Date: July 7, 1998
Creator: Dunford, C.L. & Kinsey, R.R.
Partner: UNT Libraries Government Documents Department

Uranium-233 waste definition: Disposal options, safeguards, criticality control, and arms control

Description: The US investigated the use of {sup 233}U for weapons, reactors, and other purposes from the 1950s into the 1970s. Based on the results of these investigations, it was decided not to use {sup 233}U on a large scale. Most of the {sup 233}U-containing materials were placed in long-term storage. At the end of the cold war, the US initiated, as part of its arms control policies, a disposition program for excess fissile materials. Other programs were accelerated for disposal of radioactive wastes placed in storage during the cold war. Last, potential safety issues were identified related to the storage of some {sup 233}U-containing materials. Because of these changes, significant activities associated with {sup 233}U-containing materials are expected. This report is one of a series of reports to provide the technical bases for future decisions on how to manage this material. A basis for defining when {sup 233}U-containing materials can be managed as waste and when they must be managed as concentrated fissile materials has been developed. The requirements for storage, transport, and disposal of radioactive wastes are significantly different than those for fissile materials. Because of these differences, it is important to classify material in its appropriate category. The establishment of a definition of what is waste and what is fissile material will provide the guidance for appropriate management of these materials. Wastes are defined in this report as materials containing sufficiently small masses or low concentrations of fissile materials such that they can be managed as typical radioactive waste. Concentrated fissile materials are defined herein as materials containing sufficient fissile content such as to warrant special handling to address nuclear criticality, safeguards, and arms control concerns.
Date: July 7, 1998
Creator: Forsberg, C.W.; Storch, S.N. & Lewis, L.C.
Partner: UNT Libraries Government Documents Department

CO{sub 2} mitigation and fuel production

Description: Methanol as an alternative transportation fuel appears to be an effective intermediate agent, for reducing CO{sub 2} from the utility power and the transportation sectors. On the utilization side, methanol as a liquid fuel fits in well with the current infrastructure for storage and delivery to the automotive sector with better efficiency. On the production side, CO{sub 2} from fossil fuel plants together with natural gas and biomass can be used as feedstocks for methanol synthesis with reduced CO{sub 2}. Over the past several years, processes have emerged which have varying degrees of CO{sub 2} emission reduction depending on the feedstocks used for methanol synthesis process. This paper reviews the methanol processes from the point of view of production efficiency and CO{sub 2} emissions reduction. The processes include: (1) the Hydrocarb Process which primarily utilizes coal and natural gas and stores carbon, and (2) the Hynol Process which utilizes biomass (including carbonaceous wastes, municipal solid waste (MSW)) or coal and natural gas, and (3) the Carnol Process which utilizes natural gas and CO{sub 2} recovered from fossil fuel fired powered plant stacks, especially coal fired plants. The Carnol System consists of power generation, methanol production and methanol utilization as an automotive fuel. The efficiency and CO{sub 2} emissions for the entire system are compared to the conventional system of petroleum derived automotive fuel (gasoline) and coal fired power generation plants. CO{sub 2} reduction by as much as 56% and 77% can be achieved when methanol is used in internal combustion and fuel cell automotive vehicles, respectively.
Date: July 7, 1997
Creator: Steinberg, M.
Partner: UNT Libraries Government Documents Department

Synthesis, characterization and application of electrode materials

Description: It has been known that significant advances in electrochemistry really depend on improvements in the sensitivity, selectivity, convenience, and/or economy of working electrodes, especially through the development of new working electrode materials. The advancement of solid state chemistry and materials science makes it possible to provide the materials which may be required as satisfactory electrode materials. The combination of solid state techniques with electrochemistry expands the applications of solid state materials and leads to the improvement of electrocatalysis. The study of Ru-Ti{sub 4}O{sub 7} and Pt-Ti{sub 4}O{sub 7} microelectrode arrays as introduced in paper 1 and paper 4, respectively, focuses on their synthesis and characterization. The synthesis is described by high temperature techniques for Ru or Pt microelectrode arrays within a conductive Ti{sub 4}O{sub 7} ceramic matrix. The characterization is based on the data obtained by x-ray diffractometry, scanning electron microscopy, voltammetry and amperometry. These microelectrode arrays show significant enhancement in current densities in comparison to solid Ru and Pt electrodes. Electrocatalysis at pyrochlore oxide Bi{sub 2}Ru{sub 2}O{sub 7.3} and Bi{sub 2}Ir{sub 2}O{sub 7} electrodes are described in paper 2 and paper 3, respectively. Details are reported for the synthesis and characterization of composite Bi{sub 2}Ru{sub 2}O{sub 7.3} electrodes. Voltammetric data are examined for evidence that oxidation can occur with transfer of oxygen to the oxidation products in the potential region corresponding to anodic discharge of H{sub 2}O with simultaneous evolution of O{sub 2}. Paper 3 includes electrocatalytic activities of composite Bi{sub 2}Ir{sub 2}O{sub 7} disk electrodes for the oxidation of I{sup -} and the reduction of IO{sub 3}{sup -}.
Date: July 7, 1995
Creator: He, L.
Partner: UNT Libraries Government Documents Department

Fault tolerance of the NIF power conditioning system

Description: The tolerance of the circuit topology proposed for the National Ignition Facility (NIF) power conditioning system to specific fault conditions is investigated. A new pulsed power circuit is proposed for the NIF which is simpler and less expensive than previous ICF systems. The inherent fault modes of the new circuit are different from the conventional approach, and must be understood to ensure adequate NIF system reliability. A test-bed which simulates the NIF capacitor module design was constructed to study the circuit design. Measurements from test-bed experiments with induced faults are compared with results from a detailed circuit model. The model is validated by the measurements and used to predict the behavior of the actual NIF module during faults. The model can be used to optimize fault tolerance of the NIF module through an appropriate distribution of circuit inductance and resistance. The experimental and modeling results are presented, and fault performance is compared with the ratings of pulsed power components. Areas are identified which require additional investigation.
Date: July 7, 1995
Creator: Larson, D.W.; Anderson, R. & Boyes, J.
Partner: UNT Libraries Government Documents Department

Implementation of ISO 10110 optics drawing standards for the National Ignition Facility

Description: LLNL plans to specify optical components for the National Ignition Facility according to ISO 10110, the new international standard for preparation of optics drawings. The standards have been approved by the international optics community and represent a fairly comprehensive language for describing optical components. We will describe our plan for implementation and experience to date in doing so.
Date: July 7, 1995
Creator: English, R.E. Jr.; Aikens, D.M. & Whistler, W.T.
Partner: UNT Libraries Government Documents Department

Plasma electrode pockels cell for ICF lasers

Description: In a plasma-electrode Pockels cell (PEPC), plasma discharges serve as transparent electrodes on each side of, an electrooptic crystal such as KDP. These plasmas facilitate rapid and uniform charging and discharging of the crystal. The authors describe PEPC technology deployed on Beamlet and envisioned for the National Ignition Facility. Performance on Beamlet is discussed in detail. They also discuss models which have shed light on PEPC operation. These models describe both the high-voltage sheath that forms near the crystal surface and the characteristics of the bulk plasma column.
Date: July 7, 1995
Creator: Rhodes, M.A.; Boley, C.D.; Tarditi, A.G. & Bauer, B.S.
Partner: UNT Libraries Government Documents Department