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Magnetic fusion with high energy self-colliding ion beams

Description: Field-reversed configurations of energetic large orbit ions with neutralizing electrons have been proposed as the basis of a fusion reactor. Vlasov equilibria consisting of a ring or an annulus have been investigated. A stability analysis has been carried out for a long thin layer of energetic ions in a low density background plasma. There is a growing body of experimental evidence from tokamaks that energetic ions slow down and diffuse in accordance with classical theory in the presence of lar… more
Date: June 1, 1992
Creator: Rostoker, N.; Wessel, F. (California Univ., Irvine, CA (United States)); Maglich, B. (Advanced Physics Corp., Irvine, CA (United States)) & Fisher, A. (Naval Research Lab., Washington, DC (United States))
Partner: UNT Libraries Government Documents Department
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Prospects for top at CDF

Description: During the next two years, the Fermilab Tavatron is expected to deliver approximately 100pb{sup {minus}1} of integrated luminosity. We describe improvements to the CDF detector since the 1988--89 collider run and discuss the prospects for the discovery of the top quark during the 1992--93 collider runs.
Date: June 3, 1992
Creator: Gerdes, D. (Chicago Univ., IL (United States))
Partner: UNT Libraries Government Documents Department
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A conceptual framework for using DOE 5700. 6C and the other DOE orders as an integrated management system; the Fermilab experience

Description: In this paper, I describe a conceptual framework that uses DOE Order 5700.6C and more than 140 other DOE Orders as an integrated management system -- but I describe it within the context of the broader sociological and cultural issues of doing research at DOE funded facilities. The conceptual framework has two components. The first involves an interpretation of the 10 criteria of DOE 5700.6C that is tailored for a research environment. The second component involves using the 10 criteria as func… more
Date: June 1, 1992
Creator: Bodnarczuk, M.
Partner: UNT Libraries Government Documents Department
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A formula for efficiency of fast wave current drive in fusion devices

Description: Fast wave current drive (FWCD) is a principal candidate for non- inductive current drive schemes in reactors. Major experiments are in progress or planned on DIII-D, JET, and Tore-Supra. A theory for FWCD was presented by two of the authors and collaborators. To minimize computations required in transport simulations, and for analytical understanding, it is very useful to have a concise analytical efficiency formula. Fisch and Karney, and Ehst and Karney have obtained empirical formulae that fi… more
Date: June 1, 1992
Creator: Chiu, S. C.; Harvey, R. W. (General Atomics, San Diego, CA (United States)); Karney, C. F. F. (Princeton Univ., NJ (United States). Plasma Physics Lab.) & Mau, T. K. (California Univ., Los Angeles, CA (United States). School of Engineering and Applied Science)
Partner: UNT Libraries Government Documents Department
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Structure and flux pinning properties of irradiation defects in YBa sub 2 Cu sub 3 O sub 7-x

Description: We review our investigations of defects produced in YBa{sub 2}Cu{sub 3}O{sub 7-x} by various forms of irradiation. The defect microstructure has been studied by transmission electron microscopy (TEM). Irradiation enhancements of flux pinning have been studied by SQUID magnetometry on single crystals. In many cases the same single crystals were used in both TEM and SQUID investigations. The primary atom recoil spectra for all the irradiations studied have been carefully calculated and used to co… more
Date: June 1, 1992
Creator: Kirk, M.A.
Partner: UNT Libraries Government Documents Department
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Induced cycle structures of the hyperoctahedral group

Description: The hyperoctahedral group B{sub n} is treated as the automorphism group of the n-dimensional hypercube, denoted Q{sub n}, which is nowadays understood to be a graph on 2{sup n} vertices. It is well-known that B{sub n} can be represented by the group of signed permutations. In other words, any signed permutation induces a permutation on the vertices of Q{sub n} which preserves adjacencies. Moreover, signed permutations also a permutation group on the edge of Q{sub n}, denoted H{sub n}. We study … more
Date: June 1, 1992
Creator: Chen, W.Y.C.
Partner: UNT Libraries Government Documents Department
open access

A strategy for end point criteria for Superfund remediation

Description: Since the inception of cleanup for hazardous waste sites, estimating target cleanup levels has been the subject of considerable investigation and debate in the Superfund remediation process. Establishing formal procedures for assessing human health risks associated with hazardous waste sites has provided a conceptual framework for determining remediation goals and target cleanup levels (TCLs) based on human health and ecological risk consideration. This approach was once considered at variance … more
Date: June 1, 1992
Creator: Hwang, S.T.
Partner: UNT Libraries Government Documents Department
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High-energy resolution, high-angular acceptance crystal monochromator

Description: The design principles, construction and characterization of a 4- bounce dispersive crystal monochromator is discussed. This monochromator is designed to reduce the bandpass of synchrotron radiation to 10--50 meV level, without sacrificing angular acceptance. This is achieved by combining an asymmetrically-cut, low order reflection with a symmetrically-cut, high order reflection in a nested configuration. This monochromator is being used as a beam conditioner for nuclear resonant scattering of s… more
Date: June 1, 1992
Creator: Toellner, T.S.; Mooney, T.; Alp, E.E. (Argonne National Lab., IL (United States)) & Shastri, S. (Cornell Univ., Ithaca, NY (United States). Dept. of Applied Physics)
Partner: UNT Libraries Government Documents Department
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Global-local finite element analysis of composite structures

Description: The development of layered finite elements has facilitated analysis of laminated composite structures. However, the analysis of a structure containing both isotropic and composite materials remains a difficult problem. A methodology has been developed to conduct a global-local'' finite element analysis. A global'' analysis of the entire structure is conducted at the appropriate loads with the composite portions replaced with an orthotropic material of equivalent materials properties. A local'' … more
Date: June 1, 1992
Creator: Deibler, J. E.
Partner: UNT Libraries Government Documents Department
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Spectroscopic and magnetic studies of tetravalent Pa and trivalent Th compounds

Description: At the beginning of the actinide series, the 5f and 6d configurations are very close in energy. Consequently, both the 5f and 6d energy level splittings may be observed experimentally in Pa{sup 4+} and Th{sup 3+} compounds. The available magnetic and optical data on these systems are reviewed.
Date: June 1, 1992
Creator: Edelstein, N.M. & Kot, W.K.
Partner: UNT Libraries Government Documents Department
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Analysis of production reactor response during a postulated Loss-of-River Water event using CONTAIN/SR

Description: This report discusses the CONTAIN/SR computer code, developed at the Savannah River Technology Center and Sandia National Laboratories for Probabilistic Safety Assessment (PSA) applications, which is used to analyze K Reactor plant conditions following a design basis earthquake to assist post-accident recovery planning. The postulated event, a Loss-of-River Water (LORW) accident, requires analysis of the K Reactor confinement system assuming seismic event-caused loss of forced air flow through … more
Date: June 1, 1992
Creator: O'Kula, K.R.; Wooten, L.A. (Westinghouse Savannah River Co., Aiken, SC (United States)) & Jenkins, T.B. (Concord Associates, Inc., Knoxville, TN (United States))
Partner: UNT Libraries Government Documents Department
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Coherent nuclear resonant optics for third generation synchrotron radiation sources

Description: The insertion-device-based, third-generation, synchrotron radiation sources now under construction in Europe, the USA, and Japan bring new opportunities and challenges in the design and manufacture of x-ray optics. These high brightness sources provide new opportunities to overcome some of the outstanding problems associated with nuclear resonant monochromatization of synchrotron radiation. New methods such as polarizing monochromators, and zone plates provide alternative methods for production… more
Date: June 1, 1992
Creator: Alp, E. E.; Mooney, T. M.; Toellner, T. (Argonne National Lab., IL (United States)); Homma, H. & Kentjana, M. (Brooklyn Coll., NY (United States))
Partner: UNT Libraries Government Documents Department
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Electron migration in 5-bromouracil-substituted DNA and oligonucleotides in irradiated aqueous solutions

Description: Results of work by other investigators support the hypothesis that negative charge can migrate in DNA. Charge transfer between nucleotides and electron migration in solid state DNA has been demonstrated, with migration distances as great as 110 bases. Here we report a series of studies on aqueous solutions of DNA and oligonucleotides in which the radiolysis of 5-bromouracil (BU) substituted for thymine is used as a molecular probe to detect and measure the extent of electron migration. In studi… more
Date: June 1, 1992
Creator: Zimbrick, J.D.; Beach, C.M.; Fuciarelli, A.G. & Sisk, E.C.
Partner: UNT Libraries Government Documents Department
open access

Weak-beam imaging of dissociated dislocations in HVEM-irradiated Fe-Ni-Cr alloys

Description: We report here on studies by weak-beam electron microscopy of the evolution of microstructures at and near preexisting line dislocations in a number of Fe-Ni-Cr alloys under electronirradiation in a high-voltage electron microscope (HVEM). The detailed observations are discussed in terms of dislocation climb mechanisms in these materials and a model based on interstitial pipe diffusion.
Date: June 1, 1992
Creator: King, S.L.; Jenkins, M.L.; Kirk, M.A. (Oxford Univ. (United Kingdom). Dept. of Materials) & English, C.A. (AEA Reactor Services, Harwell (United Kingdom). Harwell Lab.)
Partner: UNT Libraries Government Documents Department
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Applying ion-molecule reactions to studies of gas-phase protein structure

Description: Whether solution phase differences in protein higher order structure persist in the gas phase, is examined by means of proton transfer reactions on ions generated by electrospray ionization of different solution conformations. Ion-molecule reactions were carried out in the atmosphere-vacuum interface of a quadrupole mass spectrometer with a Y-shaped capillary inlet-reactor. An amine (dimethyl-, trimethyl-, or diethyl-) were delivered to one inlet arm. Reactivities of bovine cytochrome c ions sp… more
Date: June 1, 1992
Creator: Ogorzalek Loo, R. R.; Loo, J. A. & Smith, R. D.
Partner: UNT Libraries Government Documents Department
open access

Imaging algorithms for geophysical applications of impedance tomography

Description: The methods of impedance tomography may be employed to obtain images of subsurface electrical and conductivity variations. For practical reasons, voltages and currents are usually applied at locations on the ground surface or down a limited number of boreholes, but almost never over the entire surface of the region being investigated. The geophysical inversion process can be facilitated by constructing algorithms adopted to these particular geometries and to the lack of complete surface data. I… more
Date: June 2, 1992
Creator: Witten, A. J. & Molyneux, J. E.
Partner: UNT Libraries Government Documents Department
open access

Advancements in one-dimensional profiling with a long trace profiler

Description: Over the last several years the long trace profiler (LTP) has been evolving into a sophisticated machine capable of measuring surface profiles of very long dimensions. This report explains improvements, both hardware and software, that have helped to achieve accuracies and ranges in surface profiling that have been unobtainable until now. A comparison made by measuring standard optical surfaces on other instruments corroborates these accuracies.
Date: June 1, 1992
Creator: Irick, S.C. & McKinney, W.R.
Partner: UNT Libraries Government Documents Department
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Bench-marking beam-beam simulations using coherent quadrupole effects

Description: Computer simulations are used extensively in the study of the beam-beam interaction. The proliferation of such codes raises the important question of their reliability, and motivates the development of a dependable set of bench-marks. We argue that rather than detailed quantitative comparisons, the ability of different codes to predict the same qualitative physics should be used as a criterion for such bench-marks. We use the striking phenomenon of coherent quadrupole oscillations as one such b… more
Date: June 1, 1992
Creator: Krishnagopal, S. & Chin, Y. H.
Partner: UNT Libraries Government Documents Department
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Phase stability of fcc- and hcp-based intermetallics: The Ti-Al and Cd-Mg systems

Description: In this paper we summarize results of first-principles phase stability studies of fcc- and hcp-based Ti-Al alloys and of the hcp-based Cd-Mg system. In particular, heats of formation for ordered alloy compounds are calculated with the linear muffin tin orbital method; effective cluster interactions are determined from the results of these calculations and are used to derive thermodynamic properties and composition-temperature phase diagrams.
Date: June 1, 1992
Creator: Asta, M.; McCormack, R. (California Univ., Berkeley, CA (United States). Dept. of Materials Science and Mineral Engineering); van Schilfgaarde, M. (SRI International, Menlo Park, CA (United States)); Ceder, G. (Massachussetts Inst. of Tech., Cambridge, MA (United States). Dept. of Materials Science) & de Fontaine, D. (California Univ., Berkeley, CA (United States). Dept. of Materials Science and Mi
Partner: UNT Libraries Government Documents Department
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An historical review of lepton proton scattering

Description: In this talk I will try to review some of the early experiments in the field of electron-proton scattering, concentrating mostly on the inelastic scattering experiments at SLAC. Ordinarily, those experiments would be covered in the first five or ten minutes of the talks by Professor Scuilli and Drell, but this is a special year, and I will feel free to reminisce about the early days in a somewhat personal way.
Date: June 1, 1992
Creator: Taylor, R.
Partner: UNT Libraries Government Documents Department
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CPS and the Fermilab farms

Description: Cooperative Processes Software (CPS) is a parallel programming toolkit developed at the Fermi National Accelerator Laboratory. It is the most recent product in an evolution of systems aimed at finding a cost-effective solution to the enormous computing requirements in experimental high energy physics. Parallel programs written with CPS are large-grained, which means that the parallelism occurs at the subroutine level, rather than at the traditional single line of code level. This fits the requi… more
Date: June 1, 1992
Creator: Fausey, M.R.
Partner: UNT Libraries Government Documents Department
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The process of consensus on EMF: SAB review of the EPA draft document on EMF and cancer

Description: The EPA Draft Document on EMF and Cancers grew out of an earlier effort by EPA to track biological effects literature relative to radio-frequency (RF) exposure. Scope of the document was broadened to include extremely low frequency electric and magnetic fields prior to an announcement in 1986 that EPA would formally review the whole area of non-ionizing radiation. An extensive survey of the relevant bioeffects and epidemiologic literature was carried out, and writing on the document began in ea… more
Date: June 1, 1992
Creator: Wilson, B. W.
Partner: UNT Libraries Government Documents Department
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