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Uncertainties in the Effects of Burnup and Their Impact on Criticality Safety Licensing Criteria (open access)

Uncertainties in the Effects of Burnup and Their Impact on Criticality Safety Licensing Criteria

Current criteria for criticality safety for spent fuel shipping and storage casks are conservative because no credit is permitted for the effects of burnup of the fuel inside the cask. Cask designs that will transport and store large numbers of fuel assemblies (20 or more) must devote a substantial part of their payload to criticality control measures if they are to meet this criteria. The Department of Energy is developing the data necessary to support safety analyses that incorporate the effects of burnup for the next generation of spent fuel shipping casks. The efforts described here are devoted to the development of acceptance criteria that will be the basis for accepting safety analyses. Preliminary estimates of the uncertainties of the effects of burnup have been developed to provide a basis for the consideration of critically safety criteria. The criticality safety margins in a spent fuel shipping or storage cask are dominated by the portions of a fuel assembly that are in low power regions of a reactor core, and the reactor operating conditions are very different from spent fuel storage or transport cask conditions. Consequently, the experience that has been gathered during years of reactor operation does not apply directly …
Date: July 13, 1990
Creator: Carlson, Roger W. & Fisher, Larry E.
System: The UNT Digital Library
Scheduling the SSC (Superconducting Super Collider) construction as of March 1990 (open access)

Scheduling the SSC (Superconducting Super Collider) construction as of March 1990

The scheduling of the construction activities for the SSC Project involves two major concurrent emphases on design, construction, installation, and test. These two major activities include the completion of the construction project by the end of FY98 and industrially produced magnet tests by the end of FY92. Scheduling of the construction activities is further complicated by the fact that the baseline cost and schedule is still under review and negotiation with the Department of Energy and the currently anticipated funding for FY91 is somewhat less than originally requested. However, with the above limitations, the schedules presented herein are the most current at this time.
Date: July 1, 1990
Creator: Kozman, Ted
System: The UNT Digital Library
Is superplasticity in the future of nanophase materials (open access)

Is superplasticity in the future of nanophase materials

The ultrafine grain sizes and high diffusivities in nanophase materials assembled from atomic clusters suggest that these materials may have a strong tendency toward superplastic mechanical behavior. Both small grain size and enhanced diffusivity can be expected to lead to increased diffusional creep rates as well as to a significantly greater propensity for grain boundary sliding. Recent mechanical properties measurements at room temperature on nanophase Cu, Pd, and TiO{sub 2}, however, give no indications of superplasticity. Nonetheless, significant ductility has been clearly demonstrated in these studies of both nanophase ceramics and metals. The synthesis of cluster-assembled nanophase materials is described and the salient features of what is known of their structure and mechanical properties is reviewed. Finally, the answer to the question posed in the title is addressed. 34 refs., 6 figs.
Date: July 1, 1990
Creator: Siegel, R. W.
System: The UNT Digital Library
Measurements with a 35 psec gate time microchannel plate camera (open access)

Measurements with a 35 psec gate time microchannel plate camera

Measurements of the x-ray gate time of 0.2 mm thick microchannel plates with an L/D aspect ratio of 20 as opposed to the more usual L/D=40, demonstrate that gate times of 35 ps can be achieved. Good agreement with time dependent modelling is demonstrated. 7 refs., 4 figs., 2 tabs.
Date: July 1, 1990
Creator: Bell, P.E.; Kilkenny, J.D.; Hanks, R. & Landen, O.
System: The UNT Digital Library
Managing the global commons decision making and conflict resolution in response to climate change (open access)

Managing the global commons decision making and conflict resolution in response to climate change

A workshop was convened to develop a better understanding of decision-making matters concerning management of the global commons and to resolve conflicts in response to climate change. This workshop report does not provide a narrative of the proceedings. The workshop program is included, as are the abstracts of the papers that were presented. Only the introductory paper on social science research by William Riebsame and the closing summary by Richard Rockwell are reprinted here. This brief report focuses instead on the deliberations of the working groups that developed during the workshop. 4 figs., 1 tab.
Date: July 1, 1990
Creator: Rayner, S. (Oak Ridge National Lab., TN (USA)); Naegeli, W. & Lund, P. (Tennessee Univ., Knoxville, TN (USA))
System: The UNT Digital Library
Symmetrization of the beam-beam interaction in an asymmetric collider (open access)

Symmetrization of the beam-beam interaction in an asymmetric collider

This paper studies the idea of symmetrizing both the lattice and the beams of an asymmetric collider, and discusses why this regime should be within the parametric reach of the design in order to credibly ensure its performance. Also examined is the effectiveness of a simple compensation method using the emittance as a free parameter and that it does not work in all cases. At present, when there are no existing asymmetric colliders, it seems prudent to design an asymmetric collider so as to be similar to a symmetric one (without relying on a particular theory of the asymmetric beam-beam interaction that has not passed tests of fidelity). Nevertheless, one must allow for the maximum possible flexibility and freedom in adjusting those parameters that affect luminosity. Such a parameter flexibility will be essential in tuning the collider to the highest luminosity.
Date: July 1, 1990
Creator: Chin, Y. H.
System: The UNT Digital Library
From the neutron to three light neutrino species: Some highlights from sixty years of particle physics (open access)

From the neutron to three light neutrino species: Some highlights from sixty years of particle physics

I consider the beginning to modern particle physics to be in 1932--33, when James Chadwick discovered the neutron at Cambridge, England, and Carl Anderson discovered the positron in Pasadena, California. I leave out the discoveries of the electron by J. J. Thomson, the nucleus and the proton by Ernest Rutherford, as well as the photon introduced by Albert Einstein and the neutrino as hypothesized by Wolfgang Pauli, as having occurred before my time.'' I was thus able to follow -- and sometimes participate in -- all the developments of modern particle physics. The story I will tell is as the unfolding of the field looked; to me -- an experimental particle physicists. As with Rashomon, this is as I see it. To get a different point of view, and no doubt there are many, you need different observer. One might ask, what did I know about physics in the 1930s, anyway It so happens that I did hear abut Chadwick's discovery at the time, mainly because my brother Maurice was working with him in 1934 on the photo-disintegration of the deuteron, and on the first good measurement of the neutron mass. I will concentrate on the thirty years, 1930 to …
Date: July 1, 1990
Creator: Goldhaber, G.
System: The UNT Digital Library
Interface characterization of XUV multilayer reflectors using HRTEM (high-resolution transmission electron microscopy) and x-ray and XUV reflectance (open access)

Interface characterization of XUV multilayer reflectors using HRTEM (high-resolution transmission electron microscopy) and x-ray and XUV reflectance

We have examined the structure of XUV multilayer coatings using high-resolution transmission electron microscopy (HRTEM). Using a variety of techniques, we have measured the interface widths and the interface topography from the digitized TEM images, and have compared these results to x-ray and XUV reflectance measurements. We find that the structural parameters measured from the TEM images and those deduced from reflectance are consistent in light of the probable systematic errors associated with the measurement and interpretation techniques. 14 refs., 12 figs., 1 tab.
Date: July 1, 1990
Creator: Windt, D.L.; Hull, R.; Waskiewicz, W.K. & Kortright, J.B.
System: The UNT Digital Library
Design considerations for multilayer coated Schwarzschild objectives for the XUV (open access)

Design considerations for multilayer coated Schwarzschild objectives for the XUV

The performance of multilayer-coated Schwarzschild objectives, and similar near normal incidence soft x-ray focussing systems, can be affected by the changing angles of incidence for different rays and possible variations in multilayer period across the curved mirror surfaces. A design analysis which considers these issues is presented, using as an example a 20 times demagnifying Schwarzschild objective coated with molybdenum/silicon multilayers for operation at roughly 76 eV. The large bandwidth of these multilayers eases requirements on control of the variation of the d-spacing for the systems considered. Implications for extension to similar systems operating with different magnifications, sizes, and photon energies are discussed. 12 refs., 5 figs.
Date: July 1, 1990
Creator: Kortright, J.B. & Underwood, J.H.
System: The UNT Digital Library
Recent results from DIII-D and their implications for next generation tokamaks (open access)

Recent results from DIII-D and their implications for next generation tokamaks

Recent results from the DIII-D tokamak have provided significant contributions to the understanding of many of the elements of tokamak physics and the application of this understanding to the design of next generation devices including ITER and CIT. The limitations of magnetohydrodynamics stability on the values of plasma beta (the ratio of kinetic pressure to the containing pressure of the magnetic field) that can be attained has been experimentally demonstrated and found to be described by existing theory. Values of beta (10.7%) well in excess of those required for proposed devices (ITER and CIT) have been demonstrated. Regimes of confinement (H-mode) have been established that scale favorably to proposed next generation devices, and experiments demonstrating the dependence of the energy confinement on plasma size have been completed. Understanding of confinement is rapidly developing especially in the areas of bulk transport and the role of turbulence in the plasma edge. Key experimental results in areas of plasma transport and edge plasma phenomena are found to be in agreement with theories based on short wavelength turbulence. Control of the divertor heat loads and impurity influx has been demonstrated, and new progress has been made in the understanding of plasma edge phenomena. Experiments …
Date: July 1, 1990
Creator: Luxon, J. L.; Bramson, G.; Burrell, K. H.; Brooks, N. H.; Callis, R. W.; Carlstrom, T. N. et al.
System: The UNT Digital Library
Broad-Beam, High Current, Metal Ion Implantation Facility (open access)

Broad-Beam, High Current, Metal Ion Implantation Facility

We have developed a high current metal ion implantation facility with which high current beams of virtually all the solid metals of the Periodic Table can be produced. The facility makes use of a metal vapor vacuum arc ion source which is operated in a pulsed mode, with pulse width 0.25 ms and repetition rate up to 100 pps. Beam extraction voltage is up to 100 kV, corresponding to an ion energy of up to several hundred keV because of the ion charge state multiplicity; beam current is up to several Amperes peak and around 10 mA time averaged delivered onto target. Implantation is done in a broad-beam mode, with a direct line-of-sight from ion source to target. Here we describe the facility and some of the implants that have been carried out using it, including the seeding' of silicon wafers prior to CVD with titanium, palladium or tungsten, the formation of buried iridium silicide layers, and actinide (uranium and thorium) doping of III-V compounds. 16 refs., 6 figs.
Date: July 1, 1990
Creator: Brown, I. G.; Dickinson, M. R.; Galvin, J. E.; Godechot, X. & MacGill, R. A.
System: The UNT Digital Library
The meson spectrum between 1 and 2 GeV: Gluonic states and other exotica (open access)

The meson spectrum between 1 and 2 GeV: Gluonic states and other exotica

Present understanding of the meson spectrum is reviewed, with special attention on the search for gluonic states. Experimental progress has resulted in several paradoxes indicating states outside the {bar q}q spectrum of the nonrelativistic quark model. 59 refs., 1 fig., 2 tabs.
Date: July 20, 1990
Creator: Chanowitz, Michael S.
System: The UNT Digital Library
Striped Fabry-Perots: Improved efficiency for velocimetry (open access)

Striped Fabry-Perots: Improved efficiency for velocimetry

Removing a narrow stripe of the reflective coating from the input mirror of a Fabry-Perot interferometer can dramatically increase the amount of light transmitted through the system; we have observed gains in excess of 50 when we compare a conventional Fabry-Perot with the striped Fabry-Perot under similar lighting conditions. The stripe affects the distribution of light in the Fabry-Perot peaks causing them to be lower in the center of the pattern. We examine this distribution, and discuss its application in analyzing velocities. 6 refs., 6 figs., 1 tab.
Date: July 1, 1990
Creator: McMillan, C. & Steinmetz, L.
System: The UNT Digital Library
Proceedings of the Oak Ridge National Laboratory/Brookhaven National Laboratory workshop on neutron scattering instrumentation at high-flux reactors (open access)

Proceedings of the Oak Ridge National Laboratory/Brookhaven National Laboratory workshop on neutron scattering instrumentation at high-flux reactors

For the first three decades following World War II, the US, which pioneered the field of neutron scattering research, enjoyed uncontested leadership in the field. By the mid-1970's, other countries, most notably through the West European consortium at Institut Laue-Langevin (ILL) in Grenoble, France, had begun funding neutron scattering on a scale unmatched in this country. By the early 1980's, observers charged with defining US scientific priorities began to stress the need for upgrading and expansion of US research reactor facilities. The conceptual design of the ANS facility is now well under way, and line-item funding for more advanced design is being sought for FY 1992. This should lead to a construction request in FY 1994 and start-up in FY 1999, assuming an optimal funding profile. While it may be too early to finalize designs for instruments whose construction is nearly a decade removed, it is imperative that we begin to develop the necessary concepts to ensure state-of-the-art instrumentation for the ANS. It is in this context that this Instrumentation Workshop was planned. The workshop touched upon many ideas that must be considered for the ANS, and as anticipated, several of the discussions and findings were relevant to the planning …
Date: July 1, 1990
Creator: McBee, M. R. (ed.); Axe, J. D. & Hayter, J. B.
System: The UNT Digital Library
The practical computer in design (open access)

The practical computer in design

Electronic information processing is becoming a necessity in today's complex design environment, but what is an appropriate role for the computer in the design process Computation should be applied throughout all design phases, but practicing designers today rarely use computers beyond simple word processing and drafting tasks. While many design tasks are poorly matched to the computer, other pragmatic and productive avenues remain unexploited. We discuss the need to recognize which elements of the design process are most suited to computer assistance. The authors define a role for the computer as an objective assistant to the designer, and discuss practical approaches in two application areas for computers in design: design simulation and resource information management.
Date: July 1, 1990
Creator: Schuman, J. & Ward, G.
System: The UNT Digital Library
Passive and inherent safety technologies for light-water nuclear reactors (open access)

Passive and inherent safety technologies for light-water nuclear reactors

Passive/inherent safety implies a technical revolution in our approach to nuclear power safety. This direction is discussed herein for light-water reactors (LWRs) -- the predominant type of power reactor used in the world today. At Oak Ridge National Laboratory (ORNL) the approach to the development of passive/inherent safety for LWRs consists of four steps: identify and quantify safety requirements and goals; identify and quantify the technical functional requirements needed for safety; identify, invent, develop, and quantify technical options that meet both of the above requirements; and integrate safety systems into designs of economic and reliable nuclear power plants. Significant progress has been achieved in the first three steps of this program. The last step involves primarily the reactor vendors. These activities, as well as related activities worldwide, are described here. 27 refs., 7 tabs.
Date: July 1, 1990
Creator: Forsberg, Charles W.
System: The UNT Digital Library
CP violation experiment at Fermilab (open access)

CP violation experiment at Fermilab

The E731 experiment at Fermilab has searched for direct'' CP violation in K{sup 0} {yields} {pi}{pi}, which is parametrized by {var epsilon}{prime}/{var epsilon}. For the first time, in 20% of the data set, all four modes of the K{sub L,S} {yields} {pi}{sup +}{pi}{sup {minus}} ({pi}{sup 0}{pi}{sup 0}) were collected simultaneously, providing a great check on the systematic uncertainty. The result is Re({var epsilon}{prime}/{var epsilon}) = {minus}0.0004 {plus minus} 0.0014 (stat) {plus minus} 0.0006(syst), which provides no evidence for direct'' CP violation. The CPT symmetry has also been tested by measuring the phase difference {Delta}{phi} = {phi}{sub 00} {minus} {phi}{sub {plus minus}} between the two CP violating parameters {eta}{sub 00} and {eta}{sub {plus minus}}. We fine {Delta}{phi} = {minus}0.3{degrees} {plus minus} 2.4{degree}(stat) {plus minus} 1.2{degree}(syst). Using this together with the world average {phi}{sub {plus minus}}, we fine that the phase of the K{sup 0}-{bar K}{sup 0} mixing parameter {var epsilon} is 44.5{degree} {plus minus} 1.5{degree}. Both of these results agree well with the predictions of CPT symmetry. 17 refs., 10 figs.
Date: July 1, 1990
Creator: Hsiung, Yee B.
System: The UNT Digital Library
Long-range beam-beam interactions in the Tevatron: Comparing simulation to tune shift data (open access)

Long-range beam-beam interactions in the Tevatron: Comparing simulation to tune shift data

Fermilab upgrade plans for the collider operation include a separation scheme in the Tevatron, in which protons and antiprotons are placed on separate helical orbits. The average separation distance between the closed orbits will be 5{sigma} ({sigma} of the proton bunch) except at the interaction regions, B0 and D0, where they collide head-on. The maximum beam-beam total tune shift in the Tevatron is approximately 0.024 (the workable tune space between 5th and 7th order resonances), which was reached in the 1988--1989 collider tun. Helical separation scheme allows us to increase the luminosity by reducing the total beam-beam tune shift. The number of bunches per beam will be 6 in the 1991 collider tun, to be increased to 36 in the following collider runs. To test the viability of this scenario, helical orbit studies are being conducted. The most recent studies concentrated on the injection of 36 proton bunches, procedures related to opening and closing of the helix, the feed-down circuits and the beam-beam interaction. In this paper, we present the results of the beam-beam interaction studies only. Our emphasis is on the tune shift measurements and the comparison to simulation. 4 refs., 9 figs., 2 tabs.
Date: July 1, 1990
Creator: Saritepe, S.; Michelotti, L. & Peggs, S.
System: The UNT Digital Library
Real-space multiple scattering theory calculations of LEED (low-energy electron diffraction) intensities for stepped surfaces (open access)

Real-space multiple scattering theory calculations of LEED (low-energy electron diffraction) intensities for stepped surfaces

We use a newly developed real-space multiple scattering theory (RS-MST) to calculate low-energy electron diffraction (LEED) intensities from stepped surfaces. In this calculation the electron wavefunctions are expanded in terms of an angular momentum basis, utilizing the property of removal invariance of systems with semi-infinite periodicity. This strongly reduces the dependence of the calculation on the interlayer spacing and thus opens up the possibility of treating more open surfaces. This includes in particular stepped surfaces, to which conventional methods cannot be applied. Applications of the formalism to various stepped surfaces are presented. In particular, the results for Cu(311) and (331) surfaces obtained from both the layer doubling and RS-MST methods are compared. In addition, numerical techniques which can improve the convergence as well as the speed of the RS-MST approach are discussed. 6 refs., 3 figs.
Date: July 25, 1990
Creator: Zhang, X.-G.; Rous, P.J.; Van Hove, M.A. (Lawrence Berkeley Lab., CA (USA)); MacLaren, J.M. (Los Alamos National Lab., NM (USA)); Gonis, A. (Lawrence Livermore National Lab., CA (USA)) & Somorjai, G.A. (Lawrence Berkeley Lab., CA (USA) California Univ., Berkeley, CA (USA). Dept. of Chemistry)
System: The UNT Digital Library
Atomic physics of highly charged ions in an electron beam ion trap (open access)

Atomic physics of highly charged ions in an electron beam ion trap

Two electron beam ion traps are in use at LLNL for the purpose of studying the properties of very highly charged ions and their interactions with electrons. This paper reviews the operation of the traps and discusses recent experiments in three areas: precision transition energy measurements in the limit of very high ion charge, dielectronic recombination measurements for the He-like isoelectronic sequence, and measurements of x-ray polarization. 22 refs., 11 figs., 1 tab.
Date: July 1, 1990
Creator: Marrs, R.E.
System: The UNT Digital Library
Polarization Phenomena in Electromagnetic Interactions at Intermediate Energies (open access)

Polarization Phenomena in Electromagnetic Interactions at Intermediate Energies

Recent results of polarization measurements in electromagnetic interactions at intermediate energies are discussed. Prospects of polarization experiments at the new CW electron accelerators, as well as on upgraded older machines are outlined. It is concluded that polarization experiments will play a very important role in the study of the structure of the nucleon and of light nuclei.
Date: July 1, 1990
Creator: Burkert, Volker
System: The UNT Digital Library
The Munson Grapes -- A Rich Germplasm Legacy (open access)

The Munson Grapes -- A Rich Germplasm Legacy

Abstract: An historical review is presented of the contributions of TV. Munson to viticulture and the improvement of cultivated grapes. Munson developed more than 300 grape cultivars with the principal goal of combining the pest resistance and climatic adaptability of various native American grape species with the superior fruit quality of commercial cultivars. Several Munson cultivars achieved commercial importance in the early 1900's and a few are still grown today, most notably the rootstock 'Dog Ridge.' Munson's legacy is the genetic diversity within his cultivars; a valuable genetic resource for grape breeders.
Date: July 1990
Creator: Tarara, Julie M. & Hellman, Edward W.
System: The Portal to Texas History
1990 DOE/SANDIA crystalline photovoltaic technology project review meeting (open access)

1990 DOE/SANDIA crystalline photovoltaic technology project review meeting

This document serves as the proceedings for the annual project review meeting held by Sandia's Photovoltaic Cell Research Division and Photovoltaic Technology Division. It contains information supplied by each organization making a presentation at the meeting, which was held August 7 through 9, 1990 at the Sheraton Hotel in Albuquerque, New Mexico. Sessions were held to discuss national photovoltaic programs, one-sun crystalline silicon cell research, concentrator silicon cell research, concentrator 3-5 cell research, and concentrating collector development.
Date: July 1, 1990
Creator: Ruby, D. S.
System: The UNT Digital Library
Discrete Gravity (open access)

Discrete Gravity

This paper discusses the following: constructing a bit-string universe; quantized space-time; combinatorial hierarchy labels; gravitational stabilization of the proton; quantum geons; cosmological consequences; the proton-electron mass ratio, weak- electromagnetic unification; and sewgut. (LSP)
Date: July 1, 1990
Creator: Noyes, H. Pierre
System: The UNT Digital Library