2005 Applied and Environmental Microbiology Gordon Conference July 24-29, 2005 (open access)

2005 Applied and Environmental Microbiology Gordon Conference July 24-29, 2005

This report is about Applied and Environmental Microbiology on Gordon Conference
Date: April 14, 2006
Creator: Kenneth Nealson, Nancy Ryan Gray
System: The UNT Digital Library
AB INITIO AND CALPHAD THERMODYNAMICS OF MATERIALS (open access)

AB INITIO AND CALPHAD THERMODYNAMICS OF MATERIALS

Ab initio electronic structure methods can supplement CALPHAD in two major ways for subsequent applications to stability in complex alloys. The first one is rather immediate and concerns the direct input of ab initio energetics in CALPHAD databases. The other way, more involved, is the assessment of ab initio thermodynamics {acute a} la CALPHAD. It will be shown how these results can be used within CALPHAD to predict the equilibrium properties of multi-component alloys.
Date: April 14, 2004
Creator: Turchi, P A
System: The UNT Digital Library
Accelerating Full Configuration Interaction Calculations for Nuclear Structure (open access)

Accelerating Full Configuration Interaction Calculations for Nuclear Structure

One of the emerging computational approaches in nuclear physics is the full configuration interaction (FCI) method for solving the many-body nuclear Hamiltonian in a sufficiently large single-particle basis space to obtain exact answers - either directly or by extrapolation. The lowest eigenvalues and correspondingeigenvectors for very large, sparse and unstructured nuclear Hamiltonian matrices are obtained and used to evaluate additional experimental quantities. These matrices pose a significant challenge to the design and implementation of efficient and scalable algorithms for obtaining solutions on massively parallel computer systems. In this paper, we describe the computational strategies employed in a state-of-the-art FCI code MFDn (Many Fermion Dynamics - nuclear) as well as techniques we recently developed to enhance the computational efficiency of MFDn. We will demonstrate the current capability of MFDn and report the latest performance improvement we have achieved. We will also outline our future research directions.
Date: April 14, 2008
Creator: Yang, Chao; Sternberg, Philip; Maris, Pieter; Ng, Esmond; Sosonkina, Masha; Le, Hung Viet et al.
System: The UNT Digital Library
Application of RAM to Facility/Laboratory Design (open access)

Application of RAM to Facility/Laboratory Design

Reliability, Availability, and Maintainability (RAM) studies are extensively used for mission critical systems (e.g., weapons systems) to predict the RAM parameters at the preliminary design phase. A RAM methodology is presented for predicting facility/laboratory inherent availability (i.e., availability that only considers the steady-state effects of design) at the preliminary design phase in support of Department of Energy (DOE) Order 430.1A (Life Cycle Asset Management) and DOE Order 420.1B (Facility Safety). The methodology presented identifies the appropriate system-level reliability and maintainability metrics and discusses how these metrics are used in a fault tree analysis for predicting the facility/laboratory inherent availability. The inherent availability predicted is compared against design criteria to determine if changes to the facility/laboratory preliminary design are necessary to meet the required availability objective in the final design.
Date: April 14, 2008
Creator: Mohammadi, Kazem
System: The UNT Digital Library
BaBar: Direct CPV Searches (open access)

BaBar: Direct CPV Searches

Some recent BaBar measurements of CP-violation charge asymmetries in B meson decays to charmless hadronic final states are presented.
Date: April 14, 2006
Creator: Mir, L. M.
System: The UNT Digital Library
BaBar: Rare Charmless B Decays (open access)

BaBar: Rare Charmless B Decays

Three two body and two resonance decays of the B mesons have been measured using data from the BABAR detector: B{sup 0} {yields} {pi}{sup {+-}}, K{sup {-+}}, K{sup +}K{sup -}, K{sub S}{sup 0}{pi}{sup +}{pi}{sup -} and B{sup 0} {yields} a{sub 1}{sup +}(1260){pi}{sup -}. The branching ratio and that of some intermediate resonances are presented along with the Cp asymmetry of the decay B{sup 0} {yields} K*{sup +}{pi}{sup -}.
Date: April 14, 2006
Creator: Hutchcroft, D.
System: The UNT Digital Library
["Bush, GOP gays call visit positive" article, April 14, 2000] (open access)

["Bush, GOP gays call visit positive" article, April 14, 2000]

An article, written by Judy Keen and Jill Lawrence for USA Today, about a campaign meeting between presidential candidate George W. Bush and gay and lesbian Republican supporters. The article includes a picture of Bush with two of these supporters.
Date: April 14, 2000
Creator: Keen, Judy & Lawrence, Jill
System: The UNT Digital Library
["Bush Says He Won't Hesitate to Appoint Gays to Jobs" article, April 14, 2000] (open access)

["Bush Says He Won't Hesitate to Appoint Gays to Jobs" article, April 14, 2000]

An article, written by Terry M. Neal for The Washington Post, that covers the then presidential candidate George W. Bush's opinion and policy surrounding gay and lesbian workers and applicants. The piece notes the work Bush's campaign group did in the lead-up to his meeting with the Log Cabin Republicans and cites Bush's previous interviews and stances on the topics.
Date: April 14, 2000
Creator: Neal, Terry M.
System: The UNT Digital Library
Caustic Precipitation of Plutonium and Uranium with Gadolinium as a Neutron Poison (open access)

Caustic Precipitation of Plutonium and Uranium with Gadolinium as a Neutron Poison

The caustic precipitation of plutonium (Pu) and uranium (U) from Pu and U containing waste solutions has been investigated to determine whether gadolinium (Gd) could be used as a neutron poison for precipitation with greater than a fissile mass containing both Pu and enriched U. Precipitation experiments were performed using both actual samples and simulant solutions with a range of 2.6-5.16 g/L U and 0-4.3 to 1 U to Pu. Analyses were performed on solutions at intermediate pH to determine the partitioning of elements for accident scenarios. When both Pu and U were present in the solution, precipitation began at pH 4.5 and by pH 7, 99 percent of Pu and U had precipitated. When complete neutralization was achieved at pH greater than 14 with 1.2 M excess OH-, greater than 99 percent of Pu, U, and Gd had precipitated. At pH greater than 14, the particles sizes were larger and the distribution was a single mode. The ratio of hydrogen to fissile atoms in the precipitate was determined after both settling and centrifuging and indicates that sufficient water was associated with the precipitates to provide the needed neutron moderation for Gd to prevent a criticality in solutions containing up …
Date: April 14, 2005
Creator: Visser, Ann E.; Bronikowski, Michael G. & Rudisill, Tracy S.
System: The UNT Digital Library
CLASSIC MANY BODY POTENTIAL FOR CONCENTRATED ALLOYS, AND THE INVERSION OF ORDER IN FE-CR (open access)

CLASSIC MANY BODY POTENTIAL FOR CONCENTRATED ALLOYS, AND THE INVERSION OF ORDER IN FE-CR

Atomistic simulations of alloys at the classic--or empirical--level face the challenge to correctly model basic thermodynamic properties. In this work we propose a methodology to generalize many-body classic potentials to incorporate complex formation energy curves. Application to Fe-Cr allows us to correctly predict the order vs segregation tendency in this alloy, as observed experimentally and calculated with ab initio techniques, providing in this way a potential suitable for radiation damage studies.
Date: April 14, 2005
Creator: Caro, A; Crowson, D A & Caro, M
System: The UNT Digital Library
Continuous monitoring of crosswell seismic travel time (open access)

Continuous monitoring of crosswell seismic travel time

In two separate shallow field experiments, at two distancescales, we have used continuous monitoring to estimate the effect ofbarometric pressure on crosswell travel time and thereby calibrated thestress sensitivity of the rock volume between the wells. In a 3 mexperiment we found a stress sensitivity of 10-6/Pa while in a 30 mexperiment the sensitivity was 5 x 10-8 /Pa. Results from a deeper (1km), 2 month experiment at the San Andreas fault observation boreholeswill be presented if analysis is completed.
Date: April 14, 2006
Creator: Daley, Thomas M.; Silver, Paul G.; Niu, Fenglin & Majer, Ernest L.
System: The UNT Digital Library
A Coupled Model for Natural Convection and Condensation in HeatedSubsurface Enclosures Embedded in Fractured Rock (open access)

A Coupled Model for Natural Convection and Condensation in HeatedSubsurface Enclosures Embedded in Fractured Rock

In heated tunnels such as those designated for emplacementof radioactive waste at Yucca Mountain, axial temperature gradients maycause natural convection processes that can significantly influence themoisture conditions in the tunnels and in the surrounding fractured rock.Large-scale convection cells would provide an effective mechanism foraxial vapor transport, driving moisture out of the formation away fromthe heated tunnel section into cool end sections (where no waste isemplaced). To study such processes, we have developed and applied anenhanced version of TOUGH2 (Pruess et al., 1999) adding a new module thatsolves for natural convection in open cavities. The new TOUGH2 simulatorsimultaneously handles (1) the flow and energy transport processes in thefractured rock; (2) the flow and energy transport processes in thecavity; and (3) the heat and mass exchange at the rock-cavity interface.The new module is applied to simulate the future thermal-hydrological(TH) conditions within and near a representative waste emplacement tunnelat Yucca Mountain. Particular focus is on the potential for condensationalong the emplacement section, a possible result of heat outputdifferences between individual waste packages.
Date: April 14, 2006
Creator: Halecky, N.; Birkholzer, J. T.; Webb, S. W.; Peterson, P. F. & Bodvarsson, G. S.
System: The UNT Digital Library
Development of a large aperture Nb3Sn racetrack quadrupolemagnet (open access)

Development of a large aperture Nb3Sn racetrack quadrupolemagnet

The U.S. LHC Accelerator Research Program (LARP), a collaboration between BNL, FNAL, LBNL, and SLAC, has among its major objectives the development of advanced magnet technology for an LHC luminosity upgrade. The LBNL Superconducting Magnet Group supports this program with a broad effort involving design studies, Nb{sub 3}Sn conductor development, mechanical models, and basic prototypes. This paper describes the development of a large aperture Nb{sub 3}Sn racetrack quadrupole magnet using four racetrack coils from the LBNL Subscale Magnet (SM) Program. The magnet provides a gradient of 95 T/m in a 110 mm bore, with a peak field in the conductor of 11.2 T. The coils are prestressed by a mechanical structure based on a pre-tensioned aluminum shell, and axially supported with aluminum rods. The mechanical behavior has been monitored with strain gauges and the magnetic field has been measured. Results of the test are reported and analyzed.
Date: April 14, 2005
Creator: Ferracin, Paolo; Bartlett, Scott E.; Caspi, Shlomo; Dietderich,Daniel R.; Gourlay, Steven A.; Hannaford, Charles R. et al.
System: The UNT Digital Library
The effects of surface damage on RF cavity operation (open access)

The effects of surface damage on RF cavity operation

We describe a model of damage in rf cavities and show how this damage can limit cavity operation. We first present a review of mechanisms that may or may not affect the ultimate fields that can be obtained in rf cavities, assuming that mechanical stress explains the triggers of rf breakdown events. We present a method of quantifying the surface damage caused by breakdown events in terms of the spectrum of field enhancement factors, Beta, for asperities on the surface. We then model an equilibrium that can develop between damage and conditioning effects, and show how this equilibrium can determine cavity performance and show experimental evidence for this mechanism. We define three functions that quantify damage, and explain how the parameters that determine this performance can be factored out and measured. We then show how this model can quantitatively explain the dependence of cavity performance on material, frequency, pulse length, gas, power supply and other factors. The examples given in this paper are derived from a variety of incomplete data sets, so we outline an experimental program that should improve these predictions, provide mechanisms for comparing data from different facilities, and fill in many gaps in the existing data.
Date: April 14, 2006
Creator: Hassanein, A.; Insepov, Z.; Norem, J.; Moretti, A.; Qian, Z.; Bross, A. et al.
System: The UNT Digital Library
Electron Cloud Effects in High Intensity Proton Accelerators (open access)

Electron Cloud Effects in High Intensity Proton Accelerators

One of the primary concerns in the design and operation of high-intensity proton synchrotrons and accumulators is the electron cloud and associated beam loss and instabilities. Electron-cloud effects are observed at high-intensity proton machines like the Los Alamos National Laboratory's PSR and CERN's SPS, and investigated experimentally and theoretically. In the design of next-generation high-intensity proton accelerators like the Spallation Neutron Source ring, emphasis is made in minimizing electron production and in enhancing Landau damping. This paper reviews the present understanding of the electron-cloud effects and presents mitigation measures.
Date: April 14, 2002
Creator: Wei, J. & Macek, R. J.
System: The UNT Digital Library
Evaporative Evolution of Carbonate-Rich Brines from Synthetic Topopah Spring Tuff Pore Water, Yucca Mountain (open access)

Evaporative Evolution of Carbonate-Rich Brines from Synthetic Topopah Spring Tuff Pore Water, Yucca Mountain

The evaporation of a range of synthetic pore water solutions representative of the potential high-level-nuclear-waste repository at Yucca Mountain, NV is being investigated. The motivation of this work is to understand and predict the range of brine compositions that may contact the waste containers from evaporation of pore waters, because these brines could form corrosive thin films on the containers and impact their long-term integrity. A relatively complex synthetic Topopah Spring Tuff pore water was progressively concentrated by evaporation in a closed vessel, heated to 95 C in a series of sequential experiments. Periodic samples of the evaporating solution were taken to determine the evolving water chemistry. According to chemical divide theory at 25 C and 95 C our starting solution should evolve towards a high pH carbonate brine. Results at 95 C show that this solution evolves towards a complex brine that contains about 99 mol% Na{sup +} for the cations, and 71 mol% Cl{sup -}, 18 mol% {Sigma}CO{sub 2}(aq), 9 mol%SO{sub 4}{sup 2-} for the anions. Initial modeling of the evaporating solution indicates precipitation of aragonite, halite, silica, sulfate and fluoride phases. The experiments have been used to benchmark the use of the EQ3/6 geochemical code in predicting …
Date: April 14, 2004
Creator: Sutton, M; Alai, M & Carroll, S A
System: The UNT Digital Library
Examination of Flavor SU(3) in B, Bs to Kpi Decays (open access)

Examination of Flavor SU(3) in B, Bs to Kpi Decays

We update a discussion of the relation between the weak phase and the rates and CP asymmetries of several K{pi} decays of B{sup +}, B{sup 0}, and B{sub s}. We emphasize the impact of measurements of B{sub s} {yields} K{pi}. Current data indicate large SU(3) breaking in the strong phases or failure of factorization (including its application to penguin amplitudes) in K{pi} modes of B{sup 0} and B{sub s}. SU(3) and factorization only remain approximately valid if the branching ratio for B{sub s} {yields} K{sup -}{pi}{sup +} exceeds its current value of (5.00 {+-} 1.25) x 10{sup -6} by at least 50%, or if a parameter {zeta} describing ratios of form factors and decay constants is shifted from its nominal value by more than twice its estimated error.
Date: April 14, 2008
Creator: Chiang, Cheng-Wei; /Taiwan, Natl. Central U. /Taiwan, Inst. Phys.; Gronau, Michael; /SLAC; Rosner, Jonathan L. & /Chicago U., EFI /Chicago U.
System: The UNT Digital Library
Heterodimeric geranyl(geranyl)diphosphate synthase from hop (Humulus lupulus) and the evolution of monoterpene biosynthesis (open access)

Heterodimeric geranyl(geranyl)diphosphate synthase from hop (Humulus lupulus) and the evolution of monoterpene biosynthesis

Article on heterodimeric geranyl(geranyl)diphosphate synthase from hop (Humulus lupulus) and the evolution of monoterpene biosynthesis.
Date: April 14, 2009
Creator: Wang, Guodong & Dixon, R. A.
System: The UNT Digital Library
A high-resolution compact Johann crystal spectrometer with the Livermore electron beam ion trap. (open access)

A high-resolution compact Johann crystal spectrometer with the Livermore electron beam ion trap.

A compact high-resolution ({lambda}/{Delta}{lambda} {approx} 10000) spherically bent crystal spectrometer in the Johann geometry was recently installed and tested on the Lawrence Livermore National Laboratory SuperEBIT electron beam ion trap. The curvature of the mica (002) crystal grating allows for higher collection efficiency compared to the flat and cylindrically bent crystal spectrometers commonly used on the Livermore electron beam ion traps. The spectrometer's Johann configuration enables orientation of its dispersion plane to be parallel to the electron beam propagation. Used in concert with a crystal spectrometer, whose dispersion plane is perpendicular to the electron beam propagation, the polarization of x-ray emission lines can be measured.
Date: April 14, 2004
Creator: Robbins, D. L.; Chen, H.; Beiersdorfer, P.; Faenov, A. Y.; Pikuz, T. A.; May, M. J. et al.
System: The UNT Digital Library
Improved Operation and Modeling of the SSPX Spheromak (open access)

Improved Operation and Modeling of the SSPX Spheromak

None
Date: April 14, 2004
Creator: Wood, R.; Cohen, B.; Cohen, R.; Hill, D.; Hooper, E.; LoDestro, L. et al.
System: The UNT Digital Library
Insertion of a self-splicing intron into the mtDNA of atriploblastic animal (open access)

Insertion of a self-splicing intron into the mtDNA of atriploblastic animal

Nephtys longosetosa is a carnivorous polychaete worm that lives in the intertidal and subtidal zones with worldwide distribution (pleijel&rouse2001). Its mitochondrial genome has the characteristics typical of most metazoans: 37 genes; circular molecule; almost no intergenic sequence; and no significant gene rearrangements when compared to other annelid mtDNAs (booremoritz19981995). Ubiquitous features as small intergenic regions and lack of introns suggested that metazoan mtDNAs are under strong selective pressures to reduce their genome size allowing for faster replication requirements (booremoritz19981995Lynch2005). Yet, in 1996 two type I introns were found in the mtDNA of the basal metazoan Metridium senile (FigureX). Breaking a long-standing rule (absence of introns in metazoan mtDNA), this finding was later supported by the further presence of group I introns in other cnidarians. Interestingly, only the class Anthozoa within cnidarians seems to harbor such introns. Although several hundreds of triploblastic metazoan mtDNAs have been sequenced, this study is the first evidence of mitochondrial introns in triploblastic metazoans. The cox1 gene of N. longosetosa has an intron of almost 2 kbs in length. This finding represents as well the first instance of a group II intron (anthozoans harbor group I introns) in all metazoan lineages. Opposite trends are observed within …
Date: April 14, 2006
Creator: Valles, Y.; Halanych, K. & Boore, J.L.
System: The UNT Digital Library
ITER Model Coil Tests Overview: Nb3Sn Strand Properties in Cable-in-Conduit-Conductors (open access)

ITER Model Coil Tests Overview: Nb3Sn Strand Properties in Cable-in-Conduit-Conductors

During the ITER Model Coil Program two large coils and three Insert coils were built and tested. The test campaigns provided very valuable data on the Conductor in Conduit Cable (CICC) properties. The tests showed that the Nb3Sn strands in CICC behave differently than so-called witness strands, which underwent the same heat treatment. The paper describes Volt-temperature characteristics (VTC) and Volt-Ampere characteristics (VAC) measured in the tests, presents comparisons with the witness strands, and interprets the test results.
Date: April 14, 2003
Creator: Martovetsky, N. N.
System: The UNT Digital Library
Large Plate Lysimeter Efficiency for Collecting Water Transported from Soil to Ground Water (open access)

Large Plate Lysimeter Efficiency for Collecting Water Transported from Soil to Ground Water

A large, zero-tension, plate lysimeter (3.05 x 2.13 m) was installed to intercept percolating soil water at Bikini Atoll (11 35'N, 165 25'E), a former nuclear test-site. In two experiments controlled amounts of irrigation water were applied over the lysimeter and leachate water was collected. Evapotranspiration (ET) calculations were made using the Penman-Monteith equation and climate data collected at the atoll. The efficiency of the lysimeter was essentially 100% in contrast to low efficiencies reported for smaller plate lysimeters. Lysimeter design, installation, and water balance results are discussed.
Date: April 14, 2004
Creator: Robison, W. L.; Stone, E. L. & Hamilton, T. F.
System: The UNT Digital Library
LESSONS FROM THE RED BEADS (open access)

LESSONS FROM THE RED BEADS

None
Date: April 14, 2009
Creator: SS, PREVETTE
System: The UNT Digital Library