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High-Temperature Fast-Flow Reactor Kinetics Studies of the Reactions of Al with Cl₂, Al with HCl, and AlCl, with Cl₂ over Wide Temperature Ranges

Description: Article on high-temperature fast-flow reactor kinetics studies of the reactions of aluminum with chlorine, aluminum with hydrogen chloride and aluminum monochloride with chlorine over wide temperature ranges.
Date: April 12, 1988
Creator: Rogowski, Donald F.; Marshall, Paul & Fontijn, A. (Arthur)
Partner: UNT College of Arts and Sciences

Methyl jasmonate and yeast elicitor induce differential transcriptional and metabolic re-programming in cell suspension cultures of the model legume Medicago truncatula

Description: Article on methyl jasmonate and yeast elicitor induce differential transcriptional and metabolic re-programming in cell suspension cultures of the model legume Medicago truncatula.
Date: March 1, 2005
Creator: Suzuki, Hideyuki; Reddy, M. S. Srinivasa; Naoumkina, Marina A.; Aziz, Naveed; May, Gregory D.; Huhman, David et al.
Partner: UNT College of Arts and Sciences

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

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

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

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

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

The impact of episodic nonequilibrium fracture-matrix flow on repository performance at the potential Yucca Mountain site

Description: Adequate representation of fracture-matrix interaction during episodic infiltration events is crucial in making valid hydrological predictions of repository performance at Yucca Mountain. Approximations have been applied to represent fracture-matrix flow interaction, including the Equivalent Continuum Model, which assumes capillary equilibrium between fractures and matrix, and the Fracture-Matrix Model, which accounts for nonequilibrium fracture-matrix flow and transport for the eight major hydrostratigraphic units in the unsaturated zone at Yucca Mountain. 18 refs., 6 figs., 3 tabs.
Date: November 1, 1991
Creator: Buscheck, T.A.; Nitao, J.J. & Chesnut, D.A.
Partner: UNT Libraries Government Documents Department

Photon production at CDF and D0

Description: Prompt photon production has been studied in {bar p}p collisions at {radical}s = 1.8 TeV using the CDF and D0 detectors at Fermilab. The measured inclusive isolated photon spectral at CDF and Do are used to test NLO QCD predictions. The CDF result shows that additional soft radiation (K{sub T}) in excess of NLO QCD is required to explain the data. No new resonance is observed in the photon + jet mass spectrum from D0 which is consistent with NLO QCD predictions. The pseudorapidity distribution of the leading jet in photon events at CDF is compared to different parton distribution sets. The angular distribution is found to be better explained by a larger Bremsstrahlung contribution.
Date: July 1, 1995
Creator: Lamoureux, J.I.
Partner: UNT Libraries Government Documents Department