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Hanford Waste Vitrification Plant hydrogen generation study: Formation of ammonia from nitrate and nitrate in hydrogen generating systems

Description: The Hanford Waste Vitrification Plant (HWVP) is being designed for the Departrnent of Energy (DOE) to immobilize pretreated highly radioactive wastes in glass for permanent disposal in the HWVP, formic acid is added to the waste before vitrification to adjust glass redox and melter feed rheology. The operation of the glass melter and durability of the glass are affected by the glass oxidation state. Formation of a conductive metallic sludge in an over-reduced melt can result in a shortened melter lifetime. An over-oxidized melt may lead to foaming and loss of ruthenium as volatile RuO{sub 4}. Historically, foaming in the joule heated ceramic melter has been attributed to gas generation in the melt which is controlled by instruction of a reductant such as formic acid into the melter feed. Formic acid is also found to decrease the melter feed viscosity thereby facilitating pumping. This technical report discusses the noble metal catalyzed formic acid reduction of nitrite and/or nitrate to ammonia, a problem of considerable concern because of the generation of a potential ammonium nitrate explosion hazard in the plant ventilation system.
Date: February 1, 1996
Creator: King, R.B. & Bhattacharyya, N.K.
Partner: UNT Libraries Government Documents Department

Materials analysis of deposits made by the directed-light fabrication process

Description: This is the final report of a one-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The directed-light fabrication (DLF) process is a unique method of forming three-dimensional objects by fusing airborne powders in the focus of a laser beam. This process bypasses conventional ingot processing steps of casting, homogenization, extrusion, forging, and possibly some or all of the required machining. It provides a new ``near-net-shape`` fabrication technology for difficult-to-fabricate materials such as refractory metals, metal composites, intermetallics, ceramics, and possibly superconductors. This project addresses the solidification behavior during DLF processing to characterize the technique in terms of solid/liquid interface characteristics, cooling rates, and growth rates. Materials studied were Ag-Cu, Fe-Ni, 316SS, and Al-Cu.
Date: July 1, 1996
Creator: Lewis, G.; Nemec, R. & Thoma, D.
Partner: UNT Libraries Government Documents Department

Early operating and reliability experience with the CEBAF DC magnet power supplies

Description: The CEBAF accelerator is a five pass, recirculating, CW electron linear accelerator. There are a total of nine recirculation arcs connecting the two linacs. Three experimental halls are serviced by the accelerator through separate transport channels. The magnet powering system for CEBAF consists of approximately 2000 independent control channels. About 1850 of these channels are low current, trim magnet power supplies. There are 28 higher power supplies used to energize the major bending elements. Over one hundred, 20 amp, active shunts are used to vary current in selected magnets in the major dipole strings. The majority of the magnetic elements are concentrated in the arcs and transport channels. The correction dipoles, quadrupoles and sextupoles are each powered individually be a dedicated trim power supply channel. The arc and extraction channel dipoles are powered in series strings by the high powered supplies, known locally at CEBAF as `box power supplies'. Arc loads consist of some 30--40 magnets in series. Transport channel, path length control doglegs and septa box power supplies have loads ranging from 1 to 10 magnets. Shunts are installed on virtually all loads where two or more magnets are in series. At this time, 95% of the power supplies are installed and commissioned. In the past twelve months, beginning in May 1994, approximately 1200 trim magnet power supplies have been checked out. During this same period approximately 22 box power supplies and 100 shunts have been made operational. Full operation of the equipment has only been under way since early 1995. While this operation is only just beginning, much has been learned based on the reliability performance seen so far. The remainder of this paper describes the systems mentioned, their reliability problems, the fixes implemented to date, and some plans for the future. 6 refs., 3 tabs.
Date: August 1, 1996
Creator: Merz, W.; Flood, R.; Martin, E.J. & O'Sullivan, M.
Partner: UNT Libraries Government Documents Department

TOUGH2 simulations of the TEVES Project including the behavior of a single-component NAPL

Description: The TEVES (Thermal Enhanced Vapor Extraction System) Project is a demonstration of a process designed to extract solvents and chemicals contained in the Chemical Waste Landfill at Sandia National Laboratories. In this process, the ground is electrically heated, and borehole(s) within the heated zone are maintained at a vacuum to draw air and evaporated contaminants into the borehole and a subsequent treatment facility. TOUGH2 simulations have been performed to evaluate the fluid flow and heat transfer behavior of the system. The TOUGH2 version used in this study includes air, water, and a single-component non-aqueous phase liquid (NAPL). In the present simulations, an initial o-xylene inventory is assumed in the heated zone for illustration purposes. Variation in borehole (vapor extraction) vacuum, borehole location, and soil permeability were investigated. Simulations indicate that the temperatures in the soil are relatively insensitive to the magnitude of the borehole vacuum or the borehole locations. In contrast, however, the NAPL and liquid water saturation distributions are sensitive to these borehole parameters. As the borehole vacuum and air flow rate through the soil decrease, the possibility of contaminant (NAPL) migration from the heated zone into the surrounding unheated soil increases. The borehole location can also affect the likelihood of contaminant movement into the unheated soil.
Date: May 1, 1996
Creator: Webb, S.W.
Partner: UNT Libraries Government Documents Department

RCRA corrective action determination of no further action

Description: On July 27, 1990, the U.S. Environmental Protection Agency (EPA) proposed a regulatory framework (55 FR 30798) for responding to releases of hazardous waste and hazardous constituents from solid waste management units (SWMUs) at facilities seeking permits or permitted under the Resource Conservation and Recovery Act (RCRA). The proposed rule, `Corrective Action for Solid Waste Management Units at Hazardous Waste Facilities`, would create a new Subpart S under the 40 CFR 264 regulations, and outlines requirements for conducting RCRA Facility Investigations, evaluating potential remedies, and selecting and implementing remedies (i.e., corrective measures) at RCRA facilities. EPA anticipates instances where releases or suspected releases of hazardous wastes or constituents from SWMUs identified in a RCRA Facility Assessment, and subsequently addressed as part of required RCRA Facility Investigations, will be found to be non-existent or non-threatening to human health or the environment. Such releases may require no further action. For such situations, EPA proposed a mechanism for making a determination that no further corrective action is needed. This mechanism is known as a Determination of No Further Action (DNFA) (55 FR 30875). This information Brief describes what a DNFA is and discusses the mechanism for making a DNFA. This is one of a series of Information Briefs on RCRA corrective action.
Date: June 1, 1996
Partner: UNT Libraries Government Documents Department

Integrity assessment plan for PNL 300 area radioactive hazardous waste tank system. Final report

Description: The Pacific Northwest Laboratory (PNL), operated by Battelle Memorial Institute under contract to the U.S. Department of Energy, operates tank systems for the U.S. Department of Energy, Richland Operations Office (DOE-RL), that contain dangerous waste constituents as defined by Washington State Department of Ecology (WDOE) Dangerous Waste Regulations, Washington Administrative Code (WAC) 173-303-040(18). Chapter 173-303-640(2) of the WAC requires the performance of integrity assessments for each existing tank system that treats or stores dangerous waste, except those operating under interim status with compliant secondary containment. This Integrity Assessment Plan (IAP) identifies all tasks that will be performed during the integrity assessment of the PNL-operated Radioactive Liquid Waste Systems (RLWS) associated with the 324 and 325 Buildings located in the 300 Area of the Hanford Site. It describes the inspections, tests, and analyses required to assess the integrity of the PNL RLWS (tanks, ancillary equipment, and secondary containment) and provides sufficient information for adequate budgeting and control of the assessment program. It also provides necessary information to permit the Independent, Qualified, Registered Professional Engineer (IQRPE) to approve the integrity assessment program.
Date: March 1, 1996
Partner: UNT Libraries Government Documents Department

Adsorption of radionuclides on minerals studies illustrating the effect of solid phase selectivity and of mechanisms controlling sorption processes

Description: Currently, extensive research is being done on the geochemistry of Yucca Mountain, Nevada. The purpose of this research is to determine whether this location would be suitable as a permanent high-level radioactive waste repository. Site characterization tests must prove that Yucca Mountains` geology will safely isolate radioactive waste from the environment for at least 10,000 years before approval is granted. In order for this to occur, it is necessary to study the sorptive properties of the host rock, and its selectivity in sorption of solutions containing multiple radionuclides. Validation of this must occur, because in the case of a catastrophic leak, the host rock must have properties that will retard the migration of radionuclides. Columnar experimental techniques were employed using goethite, (a hydrous iron oxide), beidellite (clay mineral), & {open_quotes}nonscents{close_quotes} (a zeolitized volcanic tuff) as sorbents. These sorbents were used to measure the isotherms of an identical binary solution (Ni-Sr) to illustrate the selectivity that occurs in different minerals. In beidellite, the sorption process was ideal, while for {open_quotes}nonscents{close_quotes} there was a strong preference for Sr{sup 2+}. The sorption process was modeled (Ni-Sr {open_quotes}Nonscents{close_quotes}) using ion exchange theory as the mechanism. In goethite, the sorption of Ni-Sr showed a complete preference for Ni{sup 2+} at a pH of 7. In various other systems for goethite. Co-Ni (pH=7) was ideal (no selectivity) where the ratios in the solid and solution phases were relatively equal. Conversely in the case of the Pb-Ni system, the Pb{sup 2+} ion predominated completely in the solidphase over Ni{sup 2+} at a pH of 5.5. Noting the strong effect of pH on the sorption process in goethite, the selectivity could not necessarily be credited to ion-exchange because of possible exclusion from charged sites at low pH values.
Date: February 1, 1996
Creator: Netus, B.
Partner: UNT Libraries Government Documents Department

Waste vitrification projects throughout the US initiated by SRS

Description: Technologies are being developed by the US Department of Energy (DOE) Nuclear Facility sites to convert high-level, low-level, and mixed wastes to a solid stabilized waste form for permanent disposal. Vitrification is one of the most important and environmentally safest technologies being developed. The Environmental Protection Agency (EPA) has declared vitrification the Best Demonstrated Available Technology (BDAT) for high-level radioactive waste and produced a Handbook of Vitrification Technologies for Treatment of Hazardous and Radioactive Waste. The Defense Waste Processing Facility (DWPF) being tested at Savannah River Site (SRS) will soon begin vitrifying the high-level waste at SRS. The DOE Office of Technology Development (OTD) has taken the position that mixed waste needs to be stabilized to the highest level reasonably possible to ensure that the resulting waste forms will meet both the current and future regulatory specifications. Vitrification produces durable waste forms at volume reductions up to 97%. Large reductions in volume minimize long-term storage costs making vitrification cost effective on a life cycle basis.
Date: May 1, 1996
Creator: Jantzen, C.M.; Whitehouse, J.C.; Smith, M.E.; Ramsey, W.G. & Pickett, J.B.
Partner: UNT Libraries Government Documents Department

Information flow in the DAMA Project beyond database managers: Information flow managers

Description: To meet the demands of commercial data traffic on the information highway, a new look at managing data is necessary. One projected activity, sharing of point-of-sale information, is being considered in the Demand Activated Manufacturing Project of the American Textile Partnership project. A scenario is examined in which 100,000 retail outlets communicate over a period of days. They provide the latest estimate of demand for sewn products across a chain of 26,000 suppliers through the use of bill-of-materials explosions at four levels of detail. A new paradign the information flow manager, is developed to handle this situation, including the case where members of the supply chain fail to communicate and go out of business. Techniques for approximation are introduced to keep estimates of demand as current as possible.
Date: March 1, 1996
Creator: Russell, L.; Wolfson, O. & Yu, C.
Partner: UNT Libraries Government Documents Department

Coal/biomass fuels and the gas turbine: Utilization of solid fuels and their derivatives

Description: This paper discusses key design and development issues in utilizing coal and other solid fuels in gas turbines. These fuels may be burned in raw form or processed to produce liquids or gases in more or less refined forms. The use of such fuels in gas turbines requires resolution of technology issues which are of little or no consequence for conventional natural gas and refined oil fuels. For coal, these issues are primarily related to the solid form in which coal is naturally found and its high ash and contaminant levels. Biomass presents another set of issues similar to those of coal. Among the key areas discussed are effects of ash and contaminant level on deposition, corrosion, and erosion of turbine hot parts, with particular emphasis on deposition effects.
Date: June 1, 1996
Creator: DeCorso, M.; Newby, R.; Anson, D.; Wenglarz, R. & Wright, I.
Partner: UNT Libraries Government Documents Department

Electroforming cell design tool development

Description: The Electroforming Advisor (EFA) team has developed a prototype of an EFA, an easy-to-use design and computational problem solving environment for Electroforming. A primary goal is to enable electroformers to optimally design a cell that would make a part right the first time and with minimum cost. Computer simulations can be carried out much faster than experimentation and without hazardous waste production. The EFA prototype uses the Computer-Aided Design (CAD) and the Computer-Aided Engineering (CAE) capabilities of the Intergraph Engineering Modeling System coupled with the simulation capabilities of a locally developed three-dimensional boundary element code, BEPLATE. 1 ref., 7 figs.
Date: April 1, 1996
Creator: Giles, G.E.
Partner: UNT Libraries Government Documents Department

New vision solar system mission study. Final report

Description: The vision for the future of the planetary exploration program includes the capability to deliver {open_quotes}constellations{close_quotes} or {open_quotes}fleets{close_quotes} of microspacecraft to a planetary destination. These fleets will act in a coordinated manner to gather science data from a variety of locations on or around the target body, thus providing detailed, global coverage without requiring development of a single large, complex and costly spacecraft. Such constellations of spacecraft, coupled with advanced information processing and visualization techniques and high-rate communications, could provide the basis for development of a {open_quotes}virtual{close_quotes} {open_quotes}presence{close_quotes} in the solar system. A goal could be the near real-time delivery of planetary images and video to a wide variety of users in the general public and the science community. This will be a major step in making the solar system accessible to the public and will help make solar system exploration a part of the human experience on Earth.
Date: March 1, 1996
Creator: Mondt, J.F. & Zubrin, R.M.
Partner: UNT Libraries Government Documents Department

Fast events in protein folding

Description: The primary objective of this work was to develop a molecular understanding of how proteins achieve their native three-dimensional (folded) structures. This requires the identification and characterization of intermediates in the protein folding process on all relevant timescales, from picoseconds to seconds. The short timescale events in protein folding have been entirely unknown. Prior to this work, state-of-the-art experimental approaches were limited to milliseconds or longer, when much of the folding process is already over. The gap between theory and experiment is enormous: current theoretical and computational methods cannot realistically model folding processes with lifetimes longer than one nanosecond. This unique approach to employ laser pump-probe techniques that combine novel methods of laser flash photolysis with time-resolved vibrational spectroscopic probes of protein transients. In this scheme, a short (picosecond to nanosecond) laser photolysis pulse was used to produce an instantaneous pH or temperature jump, thereby initiating a protein folding or unfolding reaction. Structure-specific, time-resolved vibrational probes were then used to identify and characterize protein folding intermediates.
Date: April 1, 1996
Creator: Woodruff, W.; Callender, R.; Causgrove, T.; Dyer, R. & Williams, S.
Partner: UNT Libraries Government Documents Department

A coaxial ring-sidearm power extraction design

Description: We report a successful klystron power extraction design, in which a TEM coaxial mode is transmitted into TE10 mode of a WR90 rectangular waveguide at 11.42 GHz, with very little TEM reflection and almost vanishing asymmetric (TEM {r_arrow} TE11, or monopole to dipole) reflectance. Our coupler consists of a ring (disk) around the coaxial waveguide, and a coax-WR90 sidearm junction. The methods used in the design are numerical simulation, performed on the MAFIA3 T3 time- domain module and on the High Frequency Structure Simulator, and analytical treatment to guide the numerical runs. The demerit parameters (dipole reflectance and TEM reflection) can be reduced as much as desired (to zero in principle), the only limitation being computer run time and memory. Results are accurate to a few percent.
Date: January 1, 1996
Creator: Ben-Menahem, S. & Yu, D.
Partner: UNT Libraries Government Documents Department

Design of microwave vitrification systems for radioactive waste

Description: Oak Ridge National Laboratory (ORNL) is involved in the research and development of high-power microwave heating systems for the vitrification of DOE radioactive sludges. Design criteria for a continuous microwave vitrification system capable of processing a surrogate filtercake sludge representative of a typical waste-water treatment operation are discussed. A prototype 915 MHz, 75 kW microwave vitrification system or `microwave melter` is described along with some early experimental results that demonstrate a 4 to 1 volume reduction of a surrogate ORNL filtercake sludge.
Date: April 1, 1996
Creator: White, T.L.; Wilson, C.T.; Schaick, C.R. & Bostick, W.D.
Partner: UNT Libraries Government Documents Department

CLASP (Capture and Locking alignment Spring Positioner): A micromachined fiber auto-positioning device

Description: This work provides a method of mechanical alignment of an array of single mode fibers to an array of optical devices. The technique uses a micromachined metal spring, which captures a vertical, pre- positioned fiber, moves it into accurate alignment, and holds it for attachment. The spring is fabricated from electroplated mickel, using photodefined polyimide as a plating mask. The nickel is plated about 80 {mu}m thick, so that a large fiber depth is captured. In one application, the nickel springs can be aligned to optics on the back side of the substrate. This entire concept is referred to as CLASP (Capture and Locking Alignment Spring Positioner). These springs can be used for general alignment and capture of any fiber to any optical input or output device. Passive alignment of fiber arrays to {plus}/{minus} 2{mu}m accuracy has been demonstrated, with a clear path to improved accuracy.
Date: March 1, 1996
Creator: Kravitz, S. H.; Word, J. C.; Bauer, T. M.; Seigal, P. K. & Armendariz, M. G.
Partner: UNT Libraries Government Documents Department

Development of large scale production of Nd-doped phosphate glasses for megajoule-scale laser systems

Description: Nd-doped phosphate glasses are the preferred gain medium for high-peak-power lasers used for Inertial Confinement Fusion research because they have excellent energy storage and extraction characteristics. In addition, these glasses can be manufactured defect-free in large sizes and at relatively low cost. To meet the requirements of the future mega-joule size lasers, advanced laser glass manufacturing methods are being developed that would enable laser glass to be continuously produced at the rate of several thousand large (790 x 440 x 44 mm{sup 3}) plates of glass per year. This represents more than a 10 to 100-fold improvement in the scale of the present manufacturing technology.
Date: May 1, 1996
Creator: Ficini, G. & Campbell, J.H.
Partner: UNT Libraries Government Documents Department

Accelerated aging of EPDM and butyl elastomers

Description: This study was composed of three parts: a post cure study to optimize final properties of an ethylene-propylene-diene (EPDM) formulation, an accelerated aging study to compare the stress relaxation behavior of a butyl and an EPDM elastomer under compression, and a cursory evaluation of a new 70 Shore A EPDM. The optimum postcure for the EPDM was found to be 2 to 4 hours at 182{degrees}C in a vacuum. The EPDM was also shown to have superior aging characteristics compared to the butyl and is recommended for use instead of the butyl material. The physical properties for new 70 Shore A EPDM are satisfactory, and the stress relaxation behavior was only slightly inferior to the other EPDM.
Date: June 1, 1996
Creator: Wilson, M. H.
Partner: UNT Libraries Government Documents Department

Delta: An object-oriented finite element code architecture for massively parallel computers

Description: Delta is an object-oriented code architecture based on the finite element method which enables simulation of a wide range of engineering mechanics problems in a parallel processing environment. Written in C{sup ++}, Delta is a natural framework for algorithm development and for research involving coupling of mechanics from different Engineering Science disciplines. To enhance flexibility and encourage code reuse, the architecture provides a clean separation of the major aspects of finite element programming. Spatial discretization, temporal discretization, and the solution of linear and nonlinear systems of equations are each implemented separately, independent from the governing field equations. Other attractive features of the Delta architecture include support for constitutive models with internal variables, reusable ``matrix-free`` equation solvers, and support for region-to-region variations in the governing equations and the active degrees of freedom. A demonstration code built from the Delta architecture has been used in two-dimensional and three-dimensional simulations involving dynamic and quasi-static solid mechanics, transient and steady heat transport, and flow in porous media.
Date: February 1, 1996
Creator: Weatherby, J.R.; Schutt, J.A.; Peery, J.S. & Hogan, R.E.
Partner: UNT Libraries Government Documents Department

Pennsylvania life cycle costing manual

Description: Until the 1970s, it was commonplace for institutions and governments to purchase equipment based on lowest initial (first) costs. Recurring costs such as operational, maintenance, and energy costs often were not considered in the purchase decision. If an agency wanted to buy something, it published specifications and requested bids from several manufacturers. Often, the lowest bidder who met the specifications won the job, with no consideration given to the economic life of the equipment or yearly recurring costs such as energy and maintenance costs. The practice of purchasing based on lowest initial costs probably did not make good economic sense prior to 1970, and it certainly does not make good sense now. The wise person will consider all costs and benefits associated with a purchase, both initial and post-purchase, in order to make procurement decisions that are valid for the life of the equipment. This describes a method of financial analysis that considers all pertinent costs: life cycle costing (LCC).
Date: February 1, 1996
Partner: UNT Libraries Government Documents Department

Experimental and modeling investigation of aromatic and polycyclic aromatic hydrocarbon formation in a premixed ethylene flame

Description: Experimental and detailed chemical kinetic modeling has been performed to investigate aromatic and polyaromatic hydrocarbon formation pathways in a rich, sooting, ethylene-oxygen-argon premixed flame. An atmospheric pressure, laminar flat flame operated at an equivalence ratio of 2.5 was used to acquire experimental data for model validation. Gas composition analysis was conducted by an on-line gas chromatograph/mass spectrometer (GC/MS) technique. Measurements were made in the flame and post-flame zone for a number of low molecular weight species, aliphatics, aromatics and polycyclic aromatic hydrocarbons (PAHs) ranging from two to five-aromatic fused rings. The modeling results show the key reaction sequences leading to aromatic and polycyclic aromatic hydrocarbon growth involve the combination of resonantly stabilized radicals. In particular, propargyl and 1-methylallenyl combination reactions lead to benzene and methyl substituted benzene formation, while polycyclic aromatics are formed from cyclopentadienyl radicals and fused rings that have a shared C{sub 5} side structure. Naphthalene production through the reaction step of cyclopentadienyl self-combination and phenanthrene formation from indenyl and cyclopentadienyl combination were shown to be important in the flame modeling study. The removal of phenyl by O{sub 2} leading to cyclopentadienyl formation is expected to play a pivotal role in the PAH or soot precursor growth process under fuel-rich oxidation conditions.
Date: February 1, 1996
Creator: Castaldi, M.J.; Marinov, N.M. & Melius, C.F.
Partner: UNT Libraries Government Documents Department

Sorption and desorption of cesium and strontium on TA-2 and TA-41 soils and sediments

Description: Current environmental monitoring has detected radioactive contaminants in alluvial groundwater, soils, and sediments in the TA-2 and TA-41 areas along the north central edge of Los Alamos National Laboratory. Because of this contamination, this study was initiated. The objective of this study is to quantify the sorptivity of cesium and strontium onto TA-2 and TA-41 site specific soil samples under a controlled environment in the laboratory. The purposes of this work are to determine cesium and strontium sorption coefficient for these sit specific soils and to evaluate the potential transport of cesium and strontium. Based on this information, a risk assessment and remediation strategy can be developed.
Date: April 1, 1996
Creator: Kung, K. Stephen; Li, Benjamin W.; Longmire, P.A. & Fowler, M.M.
Partner: UNT Libraries Government Documents Department