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Measurements of actinide transmutation in the hard spectrum of a fast reactor (open access)

Measurements of actinide transmutation in the hard spectrum of a fast reactor

Measurements of fission and capture in {sup 235}U, {sup 238}U, {sup 239}Pu and {sup 237}Np and in their product actinides have been made following irradiation in the metal-fuel core of EBR-II. The reactor has a peak flux around 500keV and the data complement measurements in the softer spectrum of an LMFBR. Irradiations were made at the same time for a set of standard dosimeter samples. These provide a test of calculated spectra and are also used for validation of steel activations and calculated atomic displacement rates. Calculation were made with modem transport codes using ENDF/B-5.2 data. Comparisons are made, using a simple homogeneous model, producing a similar spectrum, using ENDF/B-6.2 and JEFF-2 data.
Date: November 14, 1994
Creator: Trybus, C. L.; Collins, P. J.; Maddison, D. W.; Bunde, K. A.; Pallmtag, S. & Palmiotti, G.
System: The UNT Digital Library
Scale-invariant Lipatov kernels from t-channel unitarity (open access)

Scale-invariant Lipatov kernels from t-channel unitarity

The Lipatov equation can be regarded as a reggeon Bethe-Salpeter equation in which higher-order reggeon interactions give higher-order kernels. Infra-red singular contributions in a general kernel are produced by t-channel nonsense states and the allowed kinematic forms are determined by unitarity. Ward identity and infra-red finiteness gauge invariance constraints then determine the corresponding scale-invariant part of a general higher-order kernel.
Date: November 14, 1994
Creator: Coriano, C. & White, A. R.
System: The UNT Digital Library
Negative Binomial Rits to Multiplicity Distributions From Central Collisions of {sup 16}O + Cu at 14.6A GeV/c and Intermittency (open access)

Negative Binomial Rits to Multiplicity Distributions From Central Collisions of {sup 16}O + Cu at 14.6A GeV/c and Intermittency

An `intermittency` analysis of charged particle multiplicity data from the target multiplicy array (TMA) in central collisions of {sup 16}O+Cu at 14.6 A{times}GeV/c has been published by the AGS-E802 collaboration. The centrality cut was made using the Zero degree Calorimeter and requiring that the forward energy be less than one projectile nucleon (i.e. T{sub ZCAL} <13.6 GeV). In agreement with previous measurements, an apparent power-law growth of Normalized Factorial moments with decreasing pseudorapidity interval was observed in the range 1.0{ge}{delta}{eta}{ge}0.1. In the present work, multiplicity distributions in individual pseudorapidity bins are presented for the same data. These distributions are excellently fit by Negative Binomial Distributions (NBD) in all {delta}{eta} bins, allowing, for the first time, a systematic formulation of the subject of `intermittency` in terms of distributions, rather than moments. In agreement with all previous measurements of NBD fits to multiplicity distributions in hadron and lepton reactions, the k parameter of the NBD fit for central {sup 16}O+Cu collisions is found to exhibit an apparently linear increase with the {delta}{eta} interval, albeit with a much steeper slope than for the other reactions, and a non-zero intercept, k(0){ne}0. True intermittency, {xi}{yields}0, would occur if the intercept k(0){yields}0, which is not observed …
Date: October 14, 1994
Creator: Tannenbaum, M. J.
System: The UNT Digital Library
Measurement of the temperature of cold highly charged ions produced in an electron beam ion trap (open access)

Measurement of the temperature of cold highly charged ions produced in an electron beam ion trap

The temperature of highly charged titanium ions produced and trapped in an electron beam ion trap was determined by precisely measuring the broadening of the emission line profile caused by the thermal Doppler motion. The measured temperature ranges from about 700 eV for deeply trapped ions to about 70 eV for ions in a shallow trap. The latter value represents the lowest temperature at which the x-ray emission of collisonally excited heliumlike Ti{sup 20}+ ions has ever been recorded, and the measured transitions represent the narrowest x-ray lines observed from highly charged titanium ions.
Date: September 14, 1994
Creator: Beiersdorfer, P.; Decaux, V. & Widmann, K.
System: The UNT Digital Library
Solution of potential flow problems on a network of workstations (open access)

Solution of potential flow problems on a network of workstations

This paper deals with the solution of potential flow problems via a panel or boundary element method on a network of scientific workstations. The idea is to treat the workstation network as a relatively course grained parallel computer and to distribute the work of constructing the influence coefficient matrix over the network. We make use of the Parallel Virtual Machine (PVM) software developed at the Oak Ridge National Laboratory to do the interprocess communications. We specifically address the problem of how to distribute the data across the network as well as the implementation of the parallel linear system solver.
Date: June 14, 1994
Creator: Semeraro, B. D.
System: The UNT Digital Library
Thin film conductive polymer for microactuator and micromuscle applications (open access)

Thin film conductive polymer for microactuator and micromuscle applications

Conductive polymer/polyimide bimorphic microcantilevers have been actuated vertically (out-of-plane) upon the volumetric changes induced by electrochemical doping of the polymer. The microcantilevers that are 200-500 {mu}m in length and 50-100 {mu}m in width can be fully extended from a circularly-curled geometry, and thus generate more than 100 {mu}m displacement. Dynamically the microcantilevers have been driven as fast as 1.2 Hz and the polymer was stable for over a week stored in air and light. Residual stresses in the polymer film is estimated to be as high as 254 MPa, and actuation stresses are as high as 50 MPa.
Date: April 14, 1994
Creator: Lee, A. P.; Hong, K.; Trevino, J. & Northrup, M. A.
System: The UNT Digital Library
A new fracture model for ceramics (open access)

A new fracture model for ceramics

A new fracture model for brittle materials is proposed for simple implementation and rapid use in a hydrodynamics computer code. The model predicts final penetration by a long tungsten-alloy rod into TiB{sub 2} to about 10% accuracy over a range of velocity from 1.36 to 2.65 mm/{mu}s and thickness from 8 to 40 mm.
Date: March 14, 1994
Creator: Steinberg, D. J. & Tipton, R. E.
System: The UNT Digital Library
Implications of ethanol-based fuels for greenhouse gas emissions (open access)

Implications of ethanol-based fuels for greenhouse gas emissions

The US Environmental Protection Agency has proposed a rule which would mandate that 30% of the oxygen content of reformulated gasoline be provided by renewable oxygenates. The rule would essentially require that biomass-based ethanol, or ETBE derived from ethanol, be used to supply 30% of the oxygen in reformulated gasoline. This short statement addresses the very narrow question, ``Would this rule result in a net decrease in greenhouse gas emissions?`` The challenge then is to determine how much greenhouse gas is emitted during the ethanol fuel cycle, a fuel cycle that is much less mature and less well documented than the petroleum fuel cycle. In the petroleum fuel cycle, most of the greenhouse gas emissions come from fuel combustion. In the ethanol fuel cycle most of the greenhouse gas emissions come from the fuel production processes. Details of corn productivity, fertilizer use, process efficiency, fuel source, etc. become very important. It is also important that the ethanol fuel cycle produces additional products and the greenhouse gas emissions have somehow to be allocated among the respective products. With so many variables in the ethanol fuel cycle, the concern is actually with ethanol-based additives which will be produced in response to the …
Date: February 14, 1994
Creator: Marland, G.; DeLuchi, M. A. & Wyman, C.
System: The UNT Digital Library
What is an open architecture robot controller? (open access)

What is an open architecture robot controller?

This paper addresses the issue of what is an open architecture robot controllers. Three different classifications are defined along with the various advantages and shortcomings of each approach. Knowledge from past research and new technology has been included in this analysis. The conclusions recommend a communication-based hybrid approach with well defined interfaces between modules.
Date: February 14, 1994
Creator: Ford, W.E.
System: The UNT Digital Library
The Y-12 Plant No Rad-Added Program for off-site shipment of nonradioactive hazardous waste (open access)

The Y-12 Plant No Rad-Added Program for off-site shipment of nonradioactive hazardous waste

On May 17, 1991, the US Department of Energy (DOE) issued a directive for DOE operations to cease off-site shipments of non-radioactive hazardous waste pending further clarification and approvals. A DOE Performance Objective for Certification of Non-Radioactive Hazardous Waste was issued in November 1991. In response to these directives, the Waste Management Division of Oak Ridge Y-12 Plant, with assistance from Roy F. Weston, Inc., has developed a No Rad-Added Program to provide small programmatic guidance and a set of procedures, approved by DOE, which will permit hazardous waste to be shipped from the Y-12 Plant to commercial treatment, storage, or disposal facilities after ensuring and certifying that hazardous waste has no radioactivity added as a result of DOE operations. There are serious legal and financial consequences of shipping waste containing radioactivity to an off-site facility not licensed to receive radioactive materials. Therefore, this program is designed with well-defined responsibilities and stringent documentation requirements.
Date: February 14, 1994
Creator: Cooper, K. H.; Mattie, B. K.; Williams, J. L.; Jacobs, D. G. & Roberts, K. A.
System: The UNT Digital Library
Identifying environmental safety and health requirements for the Fernald Environmental Restoration Management Corporation (open access)

Identifying environmental safety and health requirements for the Fernald Environmental Restoration Management Corporation

This presentation will describe the Fernald Environmental Restoration Management Corporation`s (FERMCO) Standards/Requirements Identification Documents (S/RlDs) Program, the unique process used to implement it, and the status of the program. We will also discuss the lessons learned as the program was implemented. The Department of Energy (DOE) established the Fernald site to produce uranium metals for the nation`s defense programs in 1953. In 1989, DOE suspended production and, in 1991, the mission of the site was formally changed to one of environmental cleanup and restoration. The site was renamed the Fernald Environmental Management Project (FEMP). FERMCO`s mission is to provide safe, early, and least-cost final clean-up of the site in compliance with all regulations and commitments. DOE has managed nuclear facilities primarily through its oversight of Management and Operating contractors. Comprehensive nuclear industry standards were absent when most DOE sites were first established, Management and Operating contractors had to apply existing non-nuclear industry standards and, in many cases, formulate new technical standards. Because it was satisfied with the operation of its facilities, DOE did not incorporate modern practices and standards as they became available. In March 1990, the Defense Nuclear Facilities Safety Board issued Recommendation 90-2, which called for DOE to …
Date: January 14, 1994
Creator: Beckman, W. H.; Cossel, S. C.; Alhadeff, N.; Porco, D. J.; Lindamood, S. B. & Beers, J. A.
System: The UNT Digital Library
Lessons learned during the D & D of Fernald Plant 7 (open access)

Lessons learned during the D & D of Fernald Plant 7

This document contains information about lessons learned from the decontamination and decommissioning of the Feed Materials Production Center in Fernald Ohio. The information relates to Plant 7 which was constructed to house processes for the reduction of uranium hexafluoride to uranium tetrafluoride. Topics discussed include: washdown, lockdown, asbestos removal, and bidding for dismantlement projects.
Date: January 14, 1994
Creator: Motl, G. P. & Borgman, T. D.
System: The UNT Digital Library
MGAU: A new analysis code for measuring {sup 235}U enrichments in arbitrary samples (open access)

MGAU: A new analysis code for measuring {sup 235}U enrichments in arbitrary samples

We have developed a computerized analysis method for determining {sup 235}U enrichment in uranium items where no suitable reference standards exist or where nonreproducible conditions make calibration impossible. The method requires no calibrations and is capable of accuracies of 1--2% in only a few minutes.
Date: January 14, 1994
Creator: Gunnink, R.; Ruhter, W. D.; Miller, P.; Goerten, J.; Swinhoe, M.; Wagner, H. et al.
System: The UNT Digital Library