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Yucca Mountain biological resources monitoring program; Annual report FY92
The US Department of Energy (DOE) is required by the Nuclear Waste Policy Act of 1982 (as amended in 1987) to study and characterize Yucca Mountain as a potential site for a geologic repository for high-level nuclear waste. During site characterization, the DOE will conduct a variety of geotechnical, geochemical, geological, and hydrological studies to determine the suitability of Yucca Mountain as a potential repository. To ensure that site characterization activities (SCA) do not adversely affect the environment at Yucca Mountain, an environmental program has been implemented to monitor and mitigate potential impacts and ensure activities comply with applicable environmental regulations. This report describes the activities and accomplishments of EG&G Energy Measurements, Inc. (EG&G/EM) during fiscal year 1992 (FY92) for six program areas within the Terrestrial Ecosystem component of the YMP environmental program. The six program areas are Site Characterization Effects, Desert Tortoises, Habitat Reclamation, Monitoring and Mitigation, Radiological Monitoring, and Biological Support.
Date:
February 1, 1993
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Experimental results: Pilot plant calcine dissolution and liquid feed stability
The dissolution of simulated Idaho Chemical Processing Plant pilot plant calcines, containing none of the radioactive actinides, lanthanides or fission products, was examined to evaluate the solubility of calcine matrix materials in acidic media. This study was a necessary precursor to dissolution and optimization experiments with actual radionuclide-containing calcines. The importance of temperature, nitric acid concentration, ratio of acid volume to calcine mass, and time on the amount, as a weight percentage of calcine dissolved, was evaluated. These parameters were studied for several representative pilot plant calcine types: (1) Run No. 74 Zirconia calcine; (2) Run No. 17 Zirconia/Sodium calcine; (3) Run No. 64 Zirconia/Sodium calcine; (3) Run No. 1027 Alumina calcine; and (4) Run No. 20 Alumina/Zirconia/Sodium calcine. Statistically designed experiments with the different pilot plant calcines indicated the effect of the studied process variables on the amount of calcine dissolved decreases in the order: Acid/Calcine Ratio > Temperature > HNO{sub 3} Concentration > Dissolution Time. The following conditions are suitable to achieve greater than 90 wt. % dissolution of most Zr, Al, or Na blend calcines: (1) Maximum nitric acid concentration of 5M; (2) Minimum acid/calcine ratio of 10 mL acid/1 gram calcine; (3) Minimum dissolution temperature of …
Date:
February 1, 1995
Creator:
Herbst, R. S.; Fryer, D. S.; Brewer, K. N.; Johnson, C. K. & Todd, T.A.
Object Type:
Report
System:
The UNT Digital Library
Laser ablation plume thermalization dynamics in background gases: Combined imaging, optical absorption and emission spectroscopy, and ion probe measurements
Combined diagnostic measurements are employed to characterize the penetration of energetic ablation plumes through background gases during a key transitional regime in which the ion flux is observed to split into distinct fast and slowed components. This apparently general phenomenon occurs over a limited range of distances at ambient pressures typically used for PLD (pulsed laser deposition) and may be important to film growth by PLD because a ``fast`` component of ions can arrive at the probe (or substrate) with little or no delay compared to propagation in vacuum. At longer distances, this ``fast`` component is completely attenuated, and only slowed distributions of ions are observed. Interestingly, this ``fast`` component is easily overlooked in imaging studies because the bright plume luminescence occurs in the slowed distribution. Time- and spatially-resolved optical absorption and emission spectroscopy are applied to experimentally determine the composition of the ``fast`` and ``slow`` propagating plume components for a single-component target ablation (yttrium) into an inert gas (argon) for correlation with quantitative imaging and ion probe measurements. The yttrium/argon system was chosen because optical absorption spectroscopy of both Y and Y+ was simultaneously possible and the inert nature of argon. Experimental results for several other systems, including Si/Ar, …
Date:
February 1, 1995
Creator:
Geohegan, D.B. & Puretzky, A.A.
Object Type:
Report
System:
The UNT Digital Library
Radionuclide migration as a function of mineralogy
The migration of radionuclides is studied as a function of mineralogy utilizing batch sorption and column experiments. The transport behavior of alkaline, alkaline-earth, and transition metals, and actinide species is studied in pure mineral separates. The solid phases utilized for these investigations are silicates, alumino-silicates, carbonates, and metal oxides and oxyhydroxides. The results of this effort are utilized to aid in the elucidation of the dominant chemical mechanisms of radionuclide migration, the prediction of radionuclide transport in conditions similar to those expected at the proposed high-level nuclear waste repository at Yucca Mountain, Nevada, and the identification of materials that act as natural geological barriers or that can be utilized as strong sorbers in engineered barriers. 9 refs., 2 figs., 2 tabs.
Date:
February 1, 1991
Creator:
Triay, I. R.; Mitchell, A. J. & Ott, M. A.
Object Type:
Article
System:
The UNT Digital Library
In situ spectroscopic ellipsometry as a surface sensitive tool to probe thin film growth.
Sputtered thin film and multilayer x-ray mirrors are made routinely at the Advanced Photon Source (APS) for the APS users. Precise film growth control and characterization are very critical in fabricating high-quality x-ray mirrors. Film thickness calibrations are carried out using in situ and ex situ spectroscopic ellipsometry, interferometry, and x-ray scattering. To better understand the growth and optical properties of different thin film systems, we have carried out a systematic study of sputtered thin films of Au, Rh, Pg Pd, Cu, and Cr, using in situ ellipsometry. Multiple data sets were obtained in situ for each film material with incremental thicknesses and were analyzed with their correlation in mind. We found that in situ spectroscopic ellipsometry as a surface-sensitive tool can also be used to probe the growth and morphology of the thin film system. This application of in situ spectroscopic ellipsometry for metal thin film systems will be discussed.
Date:
February 19, 1999
Creator:
Liu, C.
Object Type:
Article
System:
The UNT Digital Library
Magnetic profile in Nb/Si superconducting multilayers.
Polarized neutron reflectivity measurements were conducted on [Nb(100{angstrom})/Si(15{angstrom})]xN superconducting multilayers with a T{sub c} {approximately} 7.5 K. Scope of the experiment was to verify the existence of arrays of vortices parallel to the surface above the critical field H{sub cl} = 400 Oe when a magnetic field was applied parallel to the film plane. Measurements at 1.6 K and 700 Oe in the zero-field-cooled condition, and at 30 Oe after field cooling, indicated that reflectivity close to the first Bragg reflection of the multilayer was significantly dependent on the neutron spin. This effect was interpreted as due to Josephson type vortices at and around the silicon layers.
Date:
February 4, 1999
Creator:
Yusuf, S. M.
Object Type:
Article
System:
The UNT Digital Library
Sanitary landfill groundwater monitoring report. Fourth quarter 1994 and 1994 summary
Eighty-nine wells of the LFW series monitor groundwater quality in the Steed Pond Aquifer (Water Table) beneath the Sanitary Landfill at the Savannah River Site (SRS). These wells are sampled quarterly to comply with the South Carolina Department of Health and Environmental Control Domestic Waste Permit DWP-087A and as part of the SRS Groundwater Monitoring Program. Dichloromethane, a common laboratory contaminant, and trichloroethylene were the most widespread constituents exceeding standards during 1994. Benzene, chloroethene (vinyl chloride), 1,2-dichloroethane, 1,1-dichloroethylene, 1,2-dichloropropane, gross alpha, mercury, nonvolatile beta, tetrachloroethylene, and tritium also exceeded standards in one or more wells. The groundwater flow direction in the Steed Pond Aquifer (Water Table) beneath the Sanitary Landfill was to the southeast (universal transverse Mercator coordinates). The flow rate in this unit was approximately 140 ft/year during first and fourth quarters 1994.
Date:
February 1, 1995
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Preliminary demonstration of power beaming with non-coherent laser diode arrays
A preliminary demonstration of free-space electric power transmission has been conducted using non-coherent laser diode arrays as the transmitter and standard silicon photovoltaic cell arrays as the receiver. The transmitter assembly used a high-power-density array of infrared laser diode bars, water cooled via integrated microchannel heat sinks and focused by cylindrical microlenses. The diode array composite beam was refocused by a parabolic mirror over a 10 meter path, and received on a {approximately}15 x 25 cm panel of thinned single crystal high efficiency silicon solar cells. The maximum cell output obtained was several watts, and the cell output was used to drive a small motor. Due to operating constraints and unexpected effects, particularly the high nonuniformity of the output beam, both the distance and total received power in this demonstration were modest. However, the existing transmitter is capable of supplying several hundred watts of light output, with a projected received electric power in excess of 200 watts. The source radiance is approximately 5 x 10{sup 9} W/m{sup 2}-steradian. With the existing 20 cm aperture, useful power transmission over ranges to {approximately}100 meters should be achievable with a DC to DC efficiency of greater than 10%. Non-coherent sources of this type …
Date:
February 26, 1999
Creator:
Kare, J T; Militsky, F & Weisberg, A
Object Type:
Article
System:
The UNT Digital Library
Preliminary design report of a relativistic-Klystron two-beam-accelerator based power source for a 1 TeV center-of-mass next linear collider
A preliminary point design for an 11.4 GHz power source for a 1 TeV center-of-mass Next Linear Collider (NLC) based on the Relativistic-Klystron Two-Beam-Accelerator (RK-TBA) concept is presented. The present report is the result of a joint LBL-LLNL systems study. consisting of three major thrust areas: physics, engineering, and costing. The new RK-TBA point design, together with our findings in each of these areas, are reported.
Date:
February 22, 1995
Creator:
Yu, S.; Goffeney, N. & Henestroza, E.
Object Type:
Report
System:
The UNT Digital Library
Fossil energy waste management. Technology status report
This report describes the current status and recent accomplishments of the Fossil Energy Waste Management (FE WM) projects sponsored by the Morgantown Energy Technology Center (METC) of the US Department of Energy (DOE). The primary goal of the Waste Management Program is to identify and develop optimal strategies to manage solid by-products from advanced coal technologies for the purpose of ensuring the competitiveness of advanced coal technologies as a future energy source. The projects in the Fossil Energy Waste Management Program are divided into three types of activities: Waste Characterization, Disposal Technologies, and Utilization Technologies. This technology status report includes a discussion on barriers to increased use of coal by-products. Also, the major technical and nontechnical challenges currently being addressed by the FE WM program are discussed. A bibliography of 96 citations and a list of project contacts is included if the reader is interested in obtaining additional information about the FE WM program.
Date:
February 1, 1995
Creator:
Bossart, S.J. & Newman, D.A.
Object Type:
Report
System:
The UNT Digital Library
Technihadron production at a muon collider
Cross sections for relatively low-mass technihadron resonances at a {mu}{sup +}{mu}{sup -} collider are presented. Such particles would give spectacular signals at the first muon collider. They could be studied in detail at this machine, making use of its good mass resolution and ability to reconstruct purely hadronic final states.
Date:
February 1, 1998
Creator:
Womersley, John
Object Type:
Article
System:
The UNT Digital Library
Vapor Phase Detection Using Chemi-Resistor Sensor Arrays
This paper focuses on two main areas: understanding sensor response times so as to obtain improved time response in the field when needed for vapor tracking and classification, and improved theoretical understanding of the sensor response properties that generate the pattern on the array in response to a given analyte.
Date:
February 17, 1999
Creator:
Lewis, Nathan S.
Object Type:
Report
System:
The UNT Digital Library
Simulation of dynamic processes with adaptive neural networks.
Many industrial processes are highly non-linear and complex. Their simulation with first-principle or conventional input-output correlation models is not satisfactory, either because the process physics is not well understood, or it is so complex that direct simulation is either not adequately accurate, or it requires excessive computation time, especially for on-line applications. Artificial intelligence techniques (neural networks, expert systems, fuzzy logic) or their combination with simple process-physics models can be effectively used for the simulation of such processes. Feedforward (static) neural networks (FNNs) can be used effectively to model steady-state processes. They have also been used to model dynamic (time-varying) processes by adding to the network input layer input nodes that represent values of input variables at previous time steps. The number of previous time steps is problem dependent and, in general, can be determined after extensive testing. This work demonstrates that for dynamic processes that do not vary fast with respect to the retraining time of the neural network, an adaptive feedforward neural network can be an effective simulator that is free of the complexities introduced by the use of input values at previous time steps.
Date:
February 3, 1998
Creator:
Tzanos, C. P.
Object Type:
Article
System:
The UNT Digital Library
Functions and requirements for the INEL light duty utility arm gripper end effector
This gripper end effector system functions and requirements document defines the system functions that the end effector must perform as well as the requirements the design must meet. Safety, quality assurance, operations, environmental conditions, and regulatory requirements have been considered. The main purpose of this document is to provide a basis for the end effector engineering, design, and fabrication activities. The document shall be the living reference document to initiate the development activities and will be updated as system technologies are finalized.
Date:
February 1, 1995
Creator:
Pace, D.P. & Barnes, G.E.
Object Type:
Report
System:
The UNT Digital Library
Laboratory Analysis of Fluid Flow and Solute Transport Through a Variably Saturated Fracture Embedded in Porous Tuff
Laboratory techniques are developed that allow concurrent measurement of unsaturated matrix hydraulic conductivity and fracture transmissivity of fractured rock blocks. Two Apache Leap tuff blocks with natural fractures were removed from near Superior, Arizona, shaped into rectangular prisms, and instrumented in the laboratory. Porous ceramic plates provided solution to block tops at regulated pressures. Infiltration tests were performed on both test blocks. Steady flow testing of the saturated first block provided estimates of matrix hydraulic conductivity and fracture transmissivity. Fifteen centimeters of suction applied to the second block top showed that fracture flow was minimal and matrix hydraulic conductivity was an order of magnitude less than the first block saturated matrix conductivity. Coated-wire ion-selective electrodes monitored aqueous chlorided breakthrough concentrations. Minute samples of tracer solution were collected with filter paper. The techniques worked well for studying transport behavior at near-saturated flow conditions and also appear to be promising for unsaturated conditions. Breakthrough curves in the fracture and matrix, and a concentration map of chloride concentrations within the fracture, suggest preferential flows paths in the fracture and substantial diffusion into the matrix. Average travel velocity, dispersion coefficient and longitudinal dispersivity in the fracture are obtained. 67 refs., 54 figs., 23 tabs.
Date:
February 1, 1990
Creator:
Chuang, Y.; Haldeman, W. R.; Rasmussen, T. C. & Evans, D. D.
Object Type:
Report
System:
The UNT Digital Library
Noble gas isotope measurements for spent nuclear fuel reprocessing. IAEA Task 90/0A211 interim report
The nuclear fission of actinides in reactor fuel produces large quantities of Kr and Xe as fission products. Because of the high levels of fission Kr and Xe, sample collection and analysis of noble gases for spent fuel diagnostic measurements is a simple, straight-forward technique. In modern reprocessing plants with continuous dissolvers, it will not be possible to use traditional methods for isolating input batches of fuel. This study investigates the feasibility of using noble gas isotope abundance measurements (isotope correlation techniques - ICT) to solve safeguards requirements. Noble gas measurements might be able to provide an independent analysis of Pu contained within dissolves fuel, on an individual fuel assembly basis. The isotopic composition of Kr and Xe in spent fuel reflects both the composition (isotope abundance ratios) of the fission products and the effects of neutron capture on those fission products. We have reviewed the available literature for noble gas analyses of spent reactor fuel. While references are made to noble gas isotope correlations over the last 20 years, we have found little if any detailed analysis of large data sets. The literature search did find several useful reports. Of these papers, one is particularly useful for evaluating noble …
Date:
February 17, 1993
Creator:
Hudson, G. B.
Object Type:
Report
System:
The UNT Digital Library
Reactivation of an Idle Lease to Increase Heavy Oil Recovery through Application of Conventional Steam Drive Technology in a Low Dip Slope and Basin Reservoir in the Midway-Sunset Field, San Jaoquin Basin, California
A previously idle portion of the Midway-Sunset field, the ARCO Western Energy Pru Fee property, is being brought back into commercial production through tight integration of geologic characterization, geostatistical modeling, reservoir simulation, and petroleum engineering. This property, shut-in over a decade ago as economically marginal using conventional cyclic steaming methods, has a 200-300 foot thick oil column in the Monarch Sand. However, the sand lacks effective steam barriers and has a thick water-saturation zone above the oil-water contact. These factors require an innovative approach to steam flood production design that will balance optimal total oil production against economically viable steam-oil ratios and production rates. The methods used in the Class III demonstration are accessible to most operators in the Midway-Sunset field and could be used to revitalize properties with declining production of heavy oils throughout the region. In January 1997 the project entered its second and main phase with the purpose of demonstrating whether steamflood can be a more effective mode of production of the heavy, viscous oils from the Monarch Sand reservoir than the more conventional cyclic steaming. The objective is not just to produce the pilot site within the Pru Fee property south of Taft, but to test …
Date:
February 27, 1998
Creator:
Schamel, Steven
Object Type:
Report
System:
The UNT Digital Library
Impact of mental representational systems on design interface.
The purpose of the studies conducted at Argonne National Laboratory is to understand the impact mental representational systems have in identifying how user comfort parameters influence how information is to best be presented. By understanding how each individual perceives information based on the three representational systems (visual, auditory and kinesthetic modalities), it has been found that a different approach must be taken in the design of interfaces resulting in an outcome that is much more effective and representative of the users mental model. This paper will present current findings and future theories to be explored.
Date:
February 25, 1998
Creator:
Brown-VanHoozer, S. A.
Object Type:
Article
System:
The UNT Digital Library
JANUS reactor d and d project.
Argonne National Laboratory (ANL-E) has recently completed the decontamination and decommissioning (D and D) of the JANUS Reactor Facility located in Building 202. The 200 KW reactor operated from August 1963 to March 1992. The facility was used to study the effects of both high and low doses of fission neutrons in animals. There were two exposure rooms on opposite sides of the reactor and the reactor was therefore named after the two-faced Roman god. The High Dose Room was capable of specimen exposure at a dose rate of 3,600 rads per hour. During calendar year 1996 a detailed characterization of the facility was performed by ANL-E Health Physics personnel. ANL-E Analytical Services performed the required sample analysis. An Auditable Safety Analysis and an Environmental Assessment were completed. D and D plans, procedures and procurement documents were prepared and approved. A D and D subcontractor was selected and a firm, fixed price contract awarded for the field work and final survey effort. The D and D subcontractor was mobilized to ANL-E in January 1997. Electrical isolation of all reactor equipment and control panels was accomplished and the equipment removed. A total of 207,230 pounds (94,082 Kg) of lead shielding was …
Date:
February 16, 1998
Creator:
Fellhauer, C. R.
Object Type:
Article
System:
The UNT Digital Library
Four-point correlation functions in the AdS/CFT correspondence.
We examine correlation functions within the correspondence between gauged supergravity on anti-de Sitter space and N = 4 super Yang-Mills theory in Minkowski space. The imaginary parts of four-point functions in momentum space are computed, in addition to particular examples of three-point functions. Exchange diagrams for gravitons are included. The results indicate additional structure in N = 4 super Yang-Mills theory at strong 't Hooft coupling and in the large N limit.
Date:
February 9, 1999
Creator:
Chalmers, G. & Schalm, K.
Object Type:
Article
System:
The UNT Digital Library
Development of a Techno-Economic Model to Optimize DOE Spent Nuclear Fuel Disposition
The National Spent Nuclear Fuel (NSNF) Program is evaluating final disposition of spent nuclear fuel (SNE) in the Department of Energy (DOE) complex. Final disposition of SNF may require that the fuel be treated to minimize material concerns. The treatments may range from electrometallurgical treatment (EMT) and chemical dissolution to engineering controls. Treatment options and treatment locations will depend on fuel type and location of the fuel. One of the first steps associated with selecting one or more sites for treating SNF in the DOE complex is to determine the cost of each option. An economic analysis will assist in determining which fuel treatment alternative attains the optimum disposition of SNF at the lowest possible cost to the government and the public. For this study, a set of questions was developed for the EMT process for fuels at several locations. The set of questions addresses all issues associated with design, construction, and operation of a production facility. A matrix table was developed to determine questions applicable to various fuel treatment options. A work breakdown structure (WBS) was developed to identify a treatment process and costs from initial design to shipment of treatment products to final disposition. Costs can be applied …
Date:
February 1, 1998
Creator:
Ramer, R. J.; Plum, M. M.; Adams, J. P. & Dahl, C. A.
Object Type:
Article
System:
The UNT Digital Library
Nonlinear image filtering within IDP++
IDP++, image and data processing in C++, is a set of a signal processing libraries written in C++. It is a multi-dimension (up to four dimensions), multi-data type (implemented through templates) signal processing extension to C++. IDP++ takes advantage of the object-oriented compiler technology to provide ``information hiding.`` Users need only know C, not C++. Signals or data sets are treated like any other variable with a defined set of operators and functions. We here some examples of the nonlinear filter library within IDP++. Specifically, the results of MIN, MAX median, {alpha}-trimmed mean, and edge-trimmed mean filters as applied to a real aperture radar (RR) and synthetic aperture radar (SAR) data set.
Date:
February 9, 1995
Creator:
Lehman, S.K.; Wieting, M.G. & Brase, J.M.
Object Type:
Article
System:
The UNT Digital Library
In vivo argon laser vascular welding using thermal feedback: open and closed loop patency and collagen crosslinking
An in vivo study of vascular welding with a fiber-delivered argon laser was conducted using a canine model. Longitudinal arteriotomies and venotomies were treated on femoral vein and artery. Laser energy was delivered to the vessel wall via a 400 {micro}m optical fiber. The surface temperature at the center of the laser spot was monitored in real time using a hollow glass optical fiber-based two-color infrared thermometer. The surface temperature was limited by either a room-temperature saline drip or direct feedback control of the laser using a mechanical shutter to alternately pass and block the laser. Acute patency was evaluated either visually (leak/no leak) or by in vivo burst pressure measurements. Biochemical assays were performed to investigate the possible laser-induced formation or destruction of enzymatically mediated covalent crosslinks between collagen molecules. Viable welds were created both with and without the use of feedback control. Tissues maintained at 50 C using feedback control had an elevated crosslink count compared to controls, while those irradiated without feedback control experienced a decrease. Differences between the volumetric heating associated with open and closed loop protocols may account for the different effects on collagen crosslinks. Covalent mechanisms may play a role in argon laser vascular …
Date:
February 28, 1997
Creator:
Small, W., LLNL
Object Type:
Article
System:
The UNT Digital Library
Task 1.16 - Enhanced Mobility of Dense Nonaqueous-Phase Liquids (DNAPLs) Using Dissolved Humic Acids
Chlorinated solvent contamination is widespread across the U.S. Department of Energy (DOE) complex and other industrial facilities. Because of the physical properties of dense nonaqueous-phase liquids (DNAPLs), current treatment technologies are generally incapable of completely removing contamination from the source area. Incomplete removal means that the residual DNAPL WN persist as a long-term source of groundwater contamination. When DNALPs occur in the subsurface, they resist remediation, owing to low water volubility, high viscosity and interracial tension, and microbial recalcitrance. Because of their high density and polarity, they are usually found sorbed to aquifer solids or in pools on impermeable materials. Surfactants have been used with some success to reduce interracial tension between the aqueous and organic phases and improve volubility of DNAPLs. However, surfactants are expensive and toxic and exhibit an oxygen demand. An alternative is the use of dissolved humic acids in improving DNAPL mobilization and solubilization. Humic acids, a natural form of organic carbon, are abundant, inexpensive, and nontoxic; biodegrade slowly (low oxygen demand); and have excellent mobilization properties. The present work is to establish the feasibility of using hurnates for enhancing DNAPL remediation.
Date:
February 1, 1998
Creator:
Olson, Edwin S. & Kurz, Marc D.
Object Type:
Report
System:
The UNT Digital Library