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Ultra-intense, short pulse laser-plasma interactions with applications to the fast ignitor

Description: Due to the advent of chirped pulse amplification (CPA) as an efficient means of creating ultra-high intensity laser light (I > 5{times}10{sup 17} W/cm{sup 2}) in pulses less than a few picoseconds, new ideas for achieving ignition and gain in DT targets with less than 1 megajoule of input energy are currently being pursued. Two types of powerful lasers are employed in this scheme: (1) channeling beams and (2) ignition beams. The current state of laser-plasma interactions relating to this fusion scheme will be discussed. In particular, plasma physics issues in the ultra-intense regime are crucial to the success of this scheme. We compare simulation and experimental results in this highly nonlinear regime.
Date: April 1, 1995
Creator: Wilks, S. C.; Kruer, W. L.; Young, P. E.; Hammer, J. & Tabak, M.
Partner: UNT Libraries Government Documents Department

Maintenance Action Work Plan for Waste Area Grouping 1 inactive tanks 3001-B, 3004-B, T-30, and 3013 at Oak Ridge National Laboratory, Oak Ridge, Tennessee. Environmental Restoration Program

Description: This Maintenance Action Work Plan has been prepared to document the activities and procedures for the remediation of four inactive, low-level radioactive tanks at Waste Area Grouping 1, from the Category D list of tanks in the Federal Facility Agreement for the Oak Ridge Reservation (EPA et al. 1994). The four tanks to remediated are tanks 3001-B, 3004-B, T-30, and 3013. Three of the tanks (3001-B, 3004-B, and T-30) will be physically removed from the ground. Because of logistical issues associted with excavation and site access, the fourth tank (3013) will be grouted in place and permanently closed.
Date: July 1, 1995
Partner: UNT Libraries Government Documents Department

Material and processing issues for the monolithic integration of microelectronics with surface-micromachined polysilicon sensors and actuators

Description: The monolithic integration of micromechanical devices with their controlling electronics offers potential increases in performance as well as decreases in cost for these devices. Analog Devices has demonstrated the commercial viability of this integration by interleaving the micromechanical fabrication steps of an accelerometer with the microelectronic fabrication steps of its controlling electronics. Sandia`s Microelectronics Development Laboratory has integrated the micromechanical and microelectronic processing sequences in a segregated fashion. In this CMOS-first, micromechanics-last approach, conventional aluminum metallization is replaced by tungsten metallization to allow CMOS to withstand subsequent high-temperature processing during the micromechanical fabrication. This approach is a further development of an approach originally developed at UC Berkeley. Specifically, the issues of yield, repeatability, and uniformity of the tungsten/CMOS approach are addressed. Also, material issues related to the development of high-temperature diffusion barriers, adhesion layers, and low-stress films are discussed. Processing and material issues associated with alternative approaches to this integration such as micromechanics- first, CMOS-last or the interleaved process are also discussed.
Date: August 1, 1995
Creator: Smith, J.H.; Montague, S. & Sniegowski, J.J.
Partner: UNT Libraries Government Documents Department

K-Basins S/RIDS

Description: The Standards/Requirements Identification Document (S/RID) is a list of the Environmental, Safety, and Health (ES{ampersand}H) and Safeguards and Security (SAS) standards/requirements applicable to the K Basins facility.
Date: August 1, 1997
Creator: Watson, D.J.
Partner: UNT Libraries Government Documents Department

Precision solid liner experiments on Pegasus II

Description: Pulsed power systems have been used in the past to drive solid liner implosions for a variety of applications. In combination with a variety of target configurations, solid liner drivers can be used to compress working fluids, produce shock waves, and study material properties in convergent geometry. The utility of such a driver depends in part on how well-characterized the drive conditions are. This, in part, requires a pulsed power system with a well-characterized current wave form and well understood electrical parameters. At Los Alamos, the authors have developed a capacitively driven, inductive store pulsed power machine, Pegasus, which meets these needs. They have also developed an extensive suite of diagnostics which are capable of characterizing the performance of the system and of the imploding liners. Pegasus consists of a 4.3 MJ capacitor bank, with a capacitance of 850 {micro}f fired with a typical initial bank voltage of 90 kV or less. The bank resistance is about 0.5 m{Omega}, and bank plus power flow channel has a total inductance of about 24 nH. In this paper the authors consider the theory and modeling of the first precision solid liner driver fielded on the LANL Pegasus pulsed power facility.
Date: September 1, 1995
Creator: Bowers, R.L.; Brownell, J.H. & Lee, H.
Partner: UNT Libraries Government Documents Department

Microwave melt and offgas analysis results from a Ferro Corporation{reg_sign} glass frit

Description: In support of the Residue Treatment Technology (RTT) Microwave Solidification project, Waste Projects and Surface Water personnel conducted a series of experiments to determine the feasibility of encapsulating a surrogate sludge waste using the microwave melter. The surrogate waste was prepared by RTT and melted with five varying compositions of low melting glass frit supplied by the Ferro Corporation. Samples were melted using a 50% waste/50% glass frit and a 47.5% waste/47.5% glass frit/5% carbon powder. This was done to evaluate the effectiveness of carbon at reducing a sulfate-based surface scale which has been observed in previous experiments and in full-scale testing. These vitrified samples were subsequently submitted to Environmental Technology for toxicity characteristic leaching procedure (TCLP) testing. Two of the five frits tested in this experiment merit further evaluation as raw materials for the microwave melter. Ferro frit 3110 with and without carbon powder produced a crystalline product which passed TCLP testing. The quality of the melt product could be improved by increasing the melting temperature from 900{degrees}C to approximately 1150-1200{degrees}C. Ferro frit 3249 produced the optimal quality of glass based on visual observations, but failed TCLP testing for silver when melted without carbon powder. This frit requires a slightly higher melting temperature ({ge} 1200{degrees}C) compared to frit 3110 and produces a superior product. In conjunction with this work, Surface Water personnel conducted offgas analyses using a Thermal Desorption Mass Spectrometer (TDMS) on selected formulations. The offgas analyses identified and quantified water vapor (H{sub 2}O), oxygen (O{sub 2}) and carbon oxides (CO and CO{sub 2}), sulfur (S) and sulfur oxides (SO and SO{sub 2}), and nitrogen (N{sub 2}) and nitrogen oxides (NO and NO{sub 2}) that volatilized during glass formation.
Date: March 1, 1995
Creator: Phillips, J.A.; Hoffman, C.R. & Knutson, P.T.
Partner: UNT Libraries Government Documents Department

500 MW demonstration of advanced wall-fired combustion techniques for the reduction of nitrogen oxide (NO{sub x}) emissions from coal-fired boilers. Technical progress report, second quarter 1994, April 1994--June 1994

Description: This quarterly report discusses the technical progress of an Innovative Clean Coal Technology (ICCT) demonstration of advanced wall-fired combustion techniques for the reduction of nitrogen oxide (NOx) emissions from coal-fired boilers. The project is being conducted at Georgia Power Company`s Plant Hammond Unit 4 located near Rome, Georgia. The primary goal of this project is the characterization of the low NOx combustion equipment through the collection and analysis of long-term emissions data. A target of achieving fifty percent NOx reduction using combustion modifications has been established for the project. The project provides a stepwise retrofit of an advanced overfire air (AOFA) system followed by low NOx burners (LNB). During each test phase of the project, diagnostic, performance, long-term, and verification testing will be performed. These tests are used to quantify the NOx reductions of each technology and evaluate the effects of those reductions on other combustion parameters. Results are described.
Date: September 1, 1995
Partner: UNT Libraries Government Documents Department

Criticality benchmark results for the ENDF60 library with MCNP{trademark}

Description: The continuous-energy neutron data library ENDF60, for use with the Monte Carlo N-Particle radiation transport code MCNP4A, was released in the fall of 1994. The ENDF60 library is comprised of 124 nuclide data files based on the ENDF/B-VI (B-VI) evaluations through Release 2. Fifty-two percent of these B-VI evaluations are translations from ENDF/B-V (B-V). The remaining forty-eight percent are new evaluations which have sometimes changed significantly. Among these changes are greatly increased use of isotopic evaluations, more extensive resonance-parameter evaluations, and energy-angle correlated distributions for secondary particles. In particular, the upper energy limit for the resolved resonance region of {sup 235}U, {sup 238}U and {sup 239}Pu has been extended from 0.082, 4.0, and 0.301 keV to 2..25, 10.0, and 2.5 keV respectively. As regulatory oversight has advanced and performing critical experiments has become more difficult, there has been an increased reliance on computational methods. For the criticality safety community, the performance of the combined transport code and data library is of interest. The purpose of this abstract is to provide benchmarking results to aid the user in determining the best data library for their application.
Date: July 1, 1995
Creator: Keen, N.D.; Frankle, S.C. & MacFarlane, R.E.
Partner: UNT Libraries Government Documents Department

The Carnol process for CO{sub 2} mitigation from power plants and the transportation sector

Description: A CO{sub 2} mitigation process is developed which converts waste CO{sub 2}, primarily recovered from coal-fired power plant stack gases with natural gas, to produce methanol as a liquid fuel and coproduct carbon as a materials commodity. The Carnol process chemistry consists of methane decomposition to produce hydrogen which is catalytically reacted with the recovered waste CO{sub 2} to produce methanol. The carbon is either stored or sold as a materials commodity. A process design is modelled and mass and energy balances are presented as a function of reactor pressure and temperature conditions. The Carnol process is a viable alternative to sequestering CO{sub 2} in the ocean for purposes of reducing CO{sub 2} emissions from coal burning power plants. Over 90% of the CO{sub 2} from the coal burning plant is used in the process which results in a net CO{sub 2} emission reduction of over 90% compared to that obtained for conventional methanol production by steam reforming of methane. Methanol as an alternative liquid fuel for automotive engines and for fuel cells achieves additional CO{sub 2} emission reduction benefits. The economics of the process is greatly enhanced when carbon can be sold as a materials commodity. Improvement in process design and economics should be achieved by developing a molten metal (tin) methane decomposition reactor and a liquid phase, slurry catalyst, methanol synthesis reactor directly using the solvent saturated with CO{sub 2} scrubbed from the power plant stack gases. The benefits of the process warrant its further development.
Date: August 1, 1995
Creator: Steinberg, M.
Partner: UNT Libraries Government Documents Department

Preliminary analysis of core capsule x-ray spectroscopy and image results for medium-to-high growth factor implosions

Description: Recent capsule implosions using indirect drive on NOVA have probed core and near-core capsule T{sub e}, {rho} and mix structure using non-trivial pulse shapes (i.e. with a foot). These experiments have been performed using smooth as well as artificially roughened capsules. They have been performed using basically 3 non-trivial pulse-shapes with 3 different types of capsules with correspondingly different growth regimes for Rayleigh-Taylor instabilities. These experiments have employed time-dependent spectroscopy, gated imaging and absolutely calibrated time-integrated imaging as x-ray diagnostics. The authors compare nominal and {open_quotes}modified{close_quotes} 1D calculations with the spectroscopic and time-integrated image results. They find that the core T{sub e} is less than calculated (not surprising), but also that the T{sub e} of the inner pusher is substantially higher (at least 20%) than predicted, with perhaps some enhanced mix of the PVA layer towards the core.
Date: September 1, 1995
Creator: Pollak, G.; Delamater, N. & Landen, N.
Partner: UNT Libraries Government Documents Department

Controlling incipient oxidation of pyrite for improved rejection. Technical progress report for the ninth quarter, October 1--December 31, 1994

Description: The major objectives of this work are (1) to determine the Eh-pH conditions under which pyrite is stable, (2) to determine the mechanism of the initial stages of pyrite oxidation, and (3) to determine if the semi-conducting properties of pyrite effects its oxidation behavior. It is known that moderate oxidation of pyrite produces a hydrophobic surface product. This hydrophobic product makes it extremely difficult to depress pyrite in coal flotation circuits. The eventual objective of this work is to prevent pyrite oxidation in order to better depress pyrite in coal flotation circuits. It has been shown that by holding the potential of pyrite at its stable potential during fracture, pyrite undergoes neither oxidation nor reduction. It has also been found that fresh pyrite surfaces created by fracture in an electrochemical begin to oxidize at potentials that are about 200 mV more negative than the potentials reported in the literature for pyrite oxidation. This report period, electrochemical impedance spectroscopy (EIS) studies were continued. As discussed in the seventh quarterly progress report, the impedance of pyrite does not show the characteristics expected for either semi-conducting or metallic electrodes. Additional studies were conducted to confirm the anomalous impedance behavior. For this purpose, freshly fractured surfaces were progressively polished on 600 and 1,200 grit silicon carbide paper, and with 0.3 {micro} {alpha}-alumina and 0.05 {micro} {gamma}-alumina micropolish. Polishing is known to introduce defects in the lattice structure of semi-conducting electrodes and it was anticipated that the defects would effect the interfacial capacitance.
Date: July 1, 1995
Creator: Yoon, R.H. & Richardson, P.E.
Partner: UNT Libraries Government Documents Department

Integrated development and testing plan for the plutonium immobilization project

Description: This integrated plan for the DOE Office of Fissile Materials Disposition (MD) describes the technology development and major project activities necessary to support the deployment of the immobilization approach for disposition of surplus weapons-usable plutonium. The plan describes details of the development and testing (D&T) tasks needed to provide technical data for design and operation of a plutonium immobilization plant based on the ceramic can-in-canister technology (''Immobilization Fissile Material Disposition Program Final Immobilization Form Assessment and Recommendation'', UCRL-ID-128705, October 3, 1997). The plan also presents tasks for characterization and performance testing of the immobilization form to support a repository licensing application and to develop the basis for repository acceptance of the plutonium form. Essential elements of the plant project (design, construction, facility activation, etc.) are described, but not developed in detail, to indicate how the D&T results tie into the overall plant project. Given the importance of repository acceptance, specific activities to be conducted by the Office of Civilian Radioactive Waste Management (RW) to incorporate the plutonium form in the repository licensing application are provided in this document, together with a summary of how immobilization D&T activities provide input to the license activity. The ultimate goal of the Immobilization Project is to develop, construct, and operate facilities that will immobilize from about 18 to 50 tonnes (MT) of U.S. surplus weapons usable plutonium materials in a manner that meets the ''spent fuel'' standard (Fissile Materials Storage and Disposition Programmatic Environmental Impact Statement Record of Decision, ''Storage and Disposition Final PEIS'', issued January 14, 1997, 62 Federal Register 3014) and is acceptable for disposal in a geologic repository. In the can-in-canister technology, this is accomplished by encapsulating the plutonium-containing ceramic forms within large canisters of high level waste (HLW) glass. Deployment of the immobilization capability should occur by 2006 and be ...
Date: July 1, 1998
Creator: Kan, T.
Partner: UNT Libraries Government Documents Department

Laser tabbed die: A repairable, high-speed die-interconnection technology. 1994 LDRD final report 93-SR-089

Description: A unique technology for multichip module production is presented. The technology, called Laser Tabbed Die (L-TAB), consists of a method for forming surface-mount-type {open_quotes}gull wing{close_quotes} interconnects on bare dice. The dice are temporarily bonded to a sacrificial substrate which has a polymer thin film coated onto it. The gull wings are formed on the side of the die with a direct-write laser patterning process which allows vertical as well as horizontal image formation. Using the laser patterning system, trenches are formed in a positive electrodeposited photoresist (EDPR) which is plated onto a metal seed layer, allowing copper to be electroplated through the resultant mask. After stripping the resist and the metal seed layer, the polymer film on the substrate is dissolved, releasing the chip with the {open_quotes}gull wings{close_quotes} intact. The chips are then bonded onto a circuit board or permanent substrate with solder or conductive adhesive.
Date: September 1, 1995
Creator: Malba, V. & Bernhardt, A.F.
Partner: UNT Libraries Government Documents Department

Determination of coupled-lattice properties using turn-by-turn data

Description: A formalism for extracting coupled betatron parameters from multiturn, shock excited, beam position monitor data is described. The most important results are nonperturbative in that they do not rely on the underlying ideal lattice model. Except for damping, which is assumed to be exponential and small enough to be removed empirically, the description is symplectic. As well as simplifying the description, this leads to self-consistency checks that are applied to the data. The most important of these is a {open_quotes}magic ratio{close_quotes} of Fourier coefficients that is required to be a lattice invariant, the same at every beam position monitor. All formulas are applied to both real and simulated data. The real data was acquired June, 1992 at LEP as part of decoupling studies, using the LEP beam orbit measurement system. Simulated data, obtained by numerical tracking (TEAPOT) in the same (except for unknown errors) lattice, agrees well with real data when subjected to identical analysis. For both datasets, deviations between extracted and design parameters and deviations from self-consistency can be accounted for by noise and signal processing limitations. This investigation demonstrates that the LEP beam position system yields reliable local coupling measurements. It can be conservatively assumed that systems of similar design at the SSC and LHC will provide the measurements needed for local decoupling.
Date: December 1, 1992
Creator: Bourianoff, G.; Hunt, S. & Mathieson, D.
Partner: UNT Libraries Government Documents Department

A simplified radionuclide source term for total-system performance assessment; Yucca Mountain Site Characterization Project

Description: A parametric model for releases of radionuclides from spent-nuclear-fuel containers in a waste repository is presented. The model is appropriate for use in preliminary total-system performance assessments of the potential repository site at Yucca Mountain, Nevada; for this reason it is simpler than the models used for detailed studies of waste-package performance. Terms are included for releases from the spent fuel pellets, from the pellet/cladding gap and the grain boundaries within the fuel pellets, from the cladding of the fuel rods, and from the radioactive fuel-assembly parts. Multiple barriers are considered, including the waste container, the fuel-rod cladding, the thermal ``dry-out``, and the waste form itself. The basic formulas for release from a single fuel rod or container are extended to formulas for expected releases for the whole repository by using analytic expressions for probability distributions of some important parameters. 39 refs., 4 figs., 4 tabs.
Date: November 1, 1991
Creator: Wilson, M.L.
Partner: UNT Libraries Government Documents Department

Sediment studies at Bikini Atoll part 3. Inventories of some long-lived gamma-emitting radionuclides associated with lagoon surface sediments

Description: Surface sediment samples were collected during 1979 from 87 locations in the lagoon at Bikini Atoll. The collections were made to better define the concentrations and distribution of long-lived radionuclides associated with the bottom material and to show what modifications occurred to the composition of the surface sediment from the nuclear testing program conducted by the United States at the Atoll between 1946 and 1958. This is the last of three reports on Bikini sediment studies. In this report, we discuss the concentrations and inventories of the residual long-lived gamma-emitting radionuclides in sediments from the lagoon. The gamma-emitting radionuclides detected most frequently in sediments collected in 1979, in addition to Americium-241 ({sup 241}Am) (discussed in the second report of this series), included Cesium-137 ({sup 137}Cs), Bismuth-207 ({sup 207}Bi), Europium-155 ({sup 155}Eu), and Cobalt-60 ({sup 60}Co). Other man-made, gamma-emitting radionuclides such as Europium-152,154 ({sup 152,154}Eu), Antimony-125 ({sup 125}Sb), and Rhodium-101,102m ({sup 101,102m}Rh) were occasionally measured above detection limits in sediments near test site locations. The mean inventories for {sup 137}Cs, {sup 207}Ei, {sup 155}Eu, and {sup 60}Co in the surface 4 cm of the lagoon sediment to be 1.7, 0.56, 7.76, and 0.74 TBq, respectively. By June 1997, radioactive decay would reduce these values to 1.1, 0.38, 0.62, and 0.07 TBq, respectively. Some additional loss results from a combination of different processes that continuously mobilize and return some amount of the radionuclides to the water column. The water and dissolved constituents are removed from the lagoon through channels and exchange with the surface waters of the north equatorial Pacific Ocean. Highest levels of these radionuclides are found in surface deposits lagoonward of the Bravo Crater. Lowest concentrations and inventories are associated with sediment lagoonward of the eastern reef. The quantities in the 0-4 cm surface layer are estimated to be less ...
Date: December 1, 1997
Creator: Noshkin, V.E.
Partner: UNT Libraries Government Documents Department

Laboratory studies of radionuclide migration in tuff

Description: The movement of selected radionuclides has been observed in crushed tuff, intact tuff, and fractured tuff columns. Retardation factors and dispersivities were determined from the elution profiles. Retardation factors have been compared with those predicted on the basis of batch sorption studies. This comparison forms a basis for either validating distribution coefficients or providing evidence of speciation, including colloid formation. Dispersivities measured as a function of velocity provide a means of determining the effect of sorption kinetics or mass transfer on radionuclide migration. Dispersion is also being studied in the context of scaling symmetry to develop a basis for extrapolating from the laboratory scale to the field. 21 refs., 6 figs., 2 tabs.
Date: October 1, 1989
Creator: Rundberg, R.S.; Mitchell, A.J.; Ott, M.A.; Thompson, J.L. & Triay, I.R.
Partner: UNT Libraries Government Documents Department

Federal government, utility, manufacturer: A unique partnership for comprehensive water efficiency

Description: A partnership among the Federal government, a utility, and water efficient equipment manufacturers was developed in response to the Executive Order 12902, Energy and Efficiency in Federal Facilities, where water conservation is still a fairly undeveloped part of resource conservation in the Federal government. The Department of Energy`s Federal Energy Management Program (with the National Renewable Energy Laboratory) managed the project, bringing together the Environmental Protection Agency, General Services Administration and Bureau of Reclamation with Denver Water and four water use equipment manufacturers to install and test water-saving indoor and outdoor technologies at the Denver Federal Center. This paper will describe the process used to form this partnership and document the results and its potential impact.
Date: October 1, 1995
Creator: Mayo, K.
Partner: UNT Libraries Government Documents Department

Baseline risk assessment of ground water contamination at the uranium mill tailings site near Durango, Colorado. Revision 1

Description: For the UMTRA Project site located near Durango, Colorado (the Durango site), the Surface Project cleanup occurred from 1986 to 1991. An evaluation was made to determine whether exposure to ground water contaminated by uranium processing could affect people`s health. Exposure could occur from drinking water pumped from a hypothetical well drilled in the contaminated ground water area. In addition, environmental risks may result if plants or animals are exposed to contaminated ground water, or surface water that has mixed with contaminated ground water. This risk assessment report is the first site-specific document prepared for the UMTRA Ground Water Project at the Durango site. The results of this report and further site characterization of the Durango site will be used to determine what is necessary to protect public health and the environment, and to comply with the EPA standards.
Date: September 1, 1995
Partner: UNT Libraries Government Documents Department

Site characterization progress report: Yucca Mountain, Nevada, April 1, 1992--September 30, 1992, Number 7

Description: In accordance with section 113(b)(3) of the Nuclear Waste Policy Act of 1982, as amended (NWPA), the Department has prepared the seventh in a series of reports on the progress of site characterization at the Yucca Mountain candidate site. The Civilian Radioactive Waste Management Program made significant progress during the reporting period at the Yucca Mountain Site Characterization Project. Several important advances were made in the surface-based testing program including: initiation of borehole drilling utilizing the new, state-of-the-art LM-300 drill rig which employs dry drilling and coring techniques; neutron access borehole drilling to evaluate infiltration processes; excavations to aid geologic mapping; and trenching in Midway Valley to study Quaternary faulting. A Floodplain Assessment and Statement of Findings was published in the Federal Register which concluded there would be no significant impact nor cumulative impacts on floodplains resulting from Exploratory Studies Facility activities. The National Academy of Sciences` National Research Council released its report entitled ``Ground Water at Yucca Mountain: How High Can It Rise?`` which concluded that none of the evidence cited as proof of groundwater upwelling in and around Yucca Mountain could be reasonably attributed to that process and that significant water table excursions to the repository design level are not shown by the geologic record. The June 29, 1992, earthquake near Yucca Mountain provided scientists with a wealth of information relevant to understanding the neotectonics of the area and the geometry of faults at depth. Early findings suggest that accelerations recorded were well within proposed design limits for the surface waste handling facilities.
Date: December 1, 1992
Partner: UNT Libraries Government Documents Department