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Future impact of the experimental results from the Argonne ZGS (open access)

Future impact of the experimental results from the Argonne ZGS

Experimental programs at Argonne ZGS are reviewed with emphasis on experiments using polarized beams.
Date: January 10, 1980
Creator: Yokosawa, A.
System: The UNT Digital Library
Lactonization and protonation of gluconic acid: a thermodynamicand kinetic study by potentiometry, nmr and esi-ms (open access)

Lactonization and protonation of gluconic acid: a thermodynamicand kinetic study by potentiometry, nmr and esi-ms

In acidic aqueous solutions, gluconate protonation is coupled with lactonization of gluconic acid. With the decrease of pC{sub H}, two lactones ({delta}/{gamma}) are sequentially formed. The {delta}-lactone forms more readily than the {gamma}-lactone. In 0.1 M gluconate solutions, if pC{sub H} is above 2.5, only the {delta}-lactone is generated. When pC{sub H} is decreased below 2.0, the formation of the {gamma}-lactone is observable although the {delta}-lactone predominates. At I = 0.1 M NaClO{sub 4} and room temperature, the deprotonation constant of the carboxylic group, using the NMR technique, was determined to be log K{sub a} = 3.30 {+-} 0.02; the {delta}-lactonization constant, by the batch potentiometric titrations, was obtained to be log K{sub L} = - (0.54 {+-} 0.04). Using ESI-MS, the rate constants of the {delta}-lactonization and the hydrolysis at pC{sub H} {approx} 5.0 were estimated to be k{sub 1} = 3.2 x 10{sup -5} s{sup -1} and k{sup -1} = 1.1 x 10{sup -4} s{sup -1}, respectively.
Date: January 10, 2007
Creator: Zhang, Z.; Gibson, P.; Clark, S.B.; Tian, G.; Zanonato, P. & Rao, L.
System: The UNT Digital Library
Spin-orbit holds the heavyweight title for Pu and Am: Exchange regains it for Cm (open access)

Spin-orbit holds the heavyweight title for Pu and Am: Exchange regains it for Cm

The conclusions of this paper are: (1) The 5f electrons in Cm are near an LS coupling scheme. (2) This coupling scheme allows for a large spin polarization of the 5f electrons, which in turn stabilizes the Cm III crystal structure. (3) Results for Cm show us the recipe for magnetic stabilization of the crystal structure of metals: (A) The metal must be near the itinerant-localized transition where multiple crystal structures have close energies; (B) The metal is just on the magnetic side of the transition; and (C) There must be a magnetic moment large enough to overcome the energy difference between crystal structures, thus dictating the atomic geometry. (4) These results solidify our understanding of magnetically-stabilized metals, showing us where to look for engineered materials with magnetic applications.
Date: January 10, 2008
Creator: Moore, K; der Laan, G v & Soderlind, P
System: The UNT Digital Library
Tracking Non-rigid Structures in Computer Simulations (open access)

Tracking Non-rigid Structures in Computer Simulations

A key challenge in tracking moving objects is the correspondence problem, that is, the correct propagation of object labels from one time step to another. This is especially true when the objects are non-rigid structures, changing shape, and merging and splitting over time. In this work, we describe a general approach to tracking thousands of non-rigid structures in an image sequence. We show how we can minimize memory requirements and generate accurate results while working with only two frames of the sequence at a time. We demonstrate our results using data from computer simulations of a fluimix problem.
Date: January 10, 2008
Creator: Gezahegne, A & Kamath, C
System: The UNT Digital Library
Structure of A = 10 - 13 Nuclei with Two- Plus Three-Nucleon Interactions from Chiral Effective Field Theory (open access)

Structure of A = 10 - 13 Nuclei with Two- Plus Three-Nucleon Interactions from Chiral Effective Field Theory

Properties of finite nuclei are evaluated with two-nucleon (NN) and three-nucleon (NNN) interactions derived within chiral effective field theory (EFT). The nuclear Hamiltonian is fixed by properties of the A = 2 system, except for two low-energy constants (LECs) that parameterize the short range NNN interaction. We constrain those two LECs by a fit to the A = 3 system binding energy and investigate sensitivity of {sup 4}He, {sup 6}Li, {sup 10,11}B and {sup 12,13}C properties to the variation of the constrained LECs. We identify a preferred choice that gives globally the best description. We demonstrate that the NNN interaction terms significantly improve the binding energies and spectra of mid-p-shell nuclei not just with the preferred choice of the LECs but even within a wide range of the constrained LECs. At the same time, we find that a very high quality description of these nuclei requires further improvements to the chiral Hamiltonian.
Date: January 10, 2007
Creator: Navratil, P; Gueorguiev, V; Vary, J P; Ormand, W E & Nogga, A
System: The UNT Digital Library
Hierarchical Material Models for Fragmentation Modeling in NIF-ALE-AMR (open access)

Hierarchical Material Models for Fragmentation Modeling in NIF-ALE-AMR

Fragmentation is a fundamental process that naturally spans micro to macroscopic scales. Recent advances in algorithms, computer simulations, and hardware enable us to connect the continuum to microstructural regimes in a real simulation through a heterogeneous multiscale mathematical model. We apply this model to the problem of predicting how targets in the NIF chamber dismantle, so that optics and diagnostics can be protected from damage. The mechanics of the initial material fracture depend on the microscopic grain structure. In order to effectively simulate the fragmentation, this process must be modeled at the subgrain level with computationally expensive crystal plasticity models. However, there are not enough computational resources to model the entire NIF target at this microscopic scale. In order to accomplish these calculations, a hierarchical material model (HMM) is being developed. The HMM will allow fine-scale modeling of the initial fragmentation using computationally expensive crystal plasticity, while the elements at the mesoscale can use polycrystal models, and the macroscopic elements use analytical flow stress models. The HMM framework is built upon an adaptive mesh refinement (AMR) capability. We present progress in implementing the HMM in the NIF-ALE-AMR code. Additionally, we present test simulations relevant to NIF targets.
Date: January 10, 2008
Creator: Fisher, A C; Masters, N D; Dixit, P; Benson, D J; Koniges, A E; Anderson, R W et al.
System: The UNT Digital Library
Gel Electrophoresis of Gold-DNA Nano-Conjugates (open access)

Gel Electrophoresis of Gold-DNA Nano-Conjugates

Single stranded DNA of different lengths and different amounts was attached to colloidal phosphine stabilized Au nanoparticles. The resulting conjugates were investigated in detail by a gel electrophoresis study based on 1200 gels. We demonstrate how these experiments help to understand the binding of DNA to Au particles. In particular we compare specific attachment of DNA via gold-thiol bonds with nonspecific adsorption of DNA. The maximum number of DNA molecules that can be bound per particle was determined. We also compare several methods to used gel electrophoresis for investigating the effective diameter of DNA-Au conjugates, such as using a calibration curve of particles with known diameters and Ferguson plots.
Date: January 10, 2006
Creator: Pellegrino, T.; Sperling, R. A.; Alivisatos, A. P. & Parak, W. J.
System: The UNT Digital Library
Single sample extraction and HPLC processing for quantification of NAD and NADH levels in Saccharomyces cerevisiae (open access)

Single sample extraction and HPLC processing for quantification of NAD and NADH levels in Saccharomyces cerevisiae

A robust redox extraction protocol for quantitative and reproducible metabolite isolation and recovery has been developed for simultaneous measurement of nicotinamide adenine dinucleotide (NAD) and its reduced form, NADH, from Saccharomyces cerevisiae. Following culture in liquid media, approximately 10{sup 8} yeast cells were harvested by centrifugation and then lysed under non-oxidizing conditions by bead blasting in ice-cold, nitrogen-saturated 50-mM ammonium acetate. To enable protein denaturation, ice cold nitrogen-saturated CH{sub 3}CN + 50-mM ammonium acetate (3:1; v:v) was added to the cell lysates. After sample centrifugation to pellet precipitated proteins, organic solvent removal was performed on supernatants by chloroform extraction. The remaining aqueous phase was dried and resuspended in 50-mM ammonium acetate. NAD and NADH were separated by HPLC and quantified using UV-VIS absorbance detection. Applicability of this procedure for quantifying NAD and NADH levels was evaluated by culturing yeast under normal (2% glucose) and calorie restricted (0.5% glucose) conditions. NAD and NADH contents are similar to previously reported levels in yeast obtained using enzymatic assays performed separately on acid (for NAD) and alkali (for NADH) extracts. Results demonstrate that it is possible to perform a single preparation to reliably and robustly quantitate both NAD and NADH contents in the same …
Date: January 10, 2008
Creator: Sporty, J; Kabir, M M; Turteltaub, K; Ognibene, T; Lin, S & Bench, G
System: The UNT Digital Library
ACCELERATED-AGING OF SHIPPING PACKAGE O-RINGS FOR PU STORAGE (open access)

ACCELERATED-AGING OF SHIPPING PACKAGE O-RINGS FOR PU STORAGE

The Savannah River Site (SRS) is storing surplus plutonium (Pu) materials in the K-Area Materials Storage (KAMS) facility. The Pu materials are packaged per the DOE 3013 Standard. The nested, welded 300 series stainless steel 3013 containers are transported to KAMS in Type B shipping packages and subsequently stored in the same packages. These type B shipping packages consist of double containment vessels sealed with dual O-rings. The O-ring compound is Parker Seals V0835-75, based on Viton{reg_sign} GLT fluoroelastomer. This work evaluates the performance of the V0835-75 O-rings at accelerated-aging conditions. The results will be used to develop a lifetime prediction model for O-rings in KAMS.
Date: January 10, 2008
Creator: Hoffman, E
System: The UNT Digital Library
Image analysis for Validation of Simulations of Fluid Mix Problem (open access)

Image analysis for Validation of Simulations of Fluid Mix Problem

As computer simulations gain acceptance for the modeling of complex physical phenomena, there is an increasing need to validate these simulation codes by comparing them to experiments. Currently, this is done qualitatively, using a visual approach. This is obviously very subjective and more quantitative metrics are needed, especially to identify simulations which are closer to experiments than other simulations. In this paper, we show how image processing techniques can be effectively used in such comparisons. Using an example from the problem of mixing of two fluids, we show that we can quantitatively compare experimental and simulation images by extracting higher level features to characterize the objects in the images.
Date: January 10, 2007
Creator: Kamath, C & Miller, P
System: The UNT Digital Library
Transcription Factors Bind Thousands of Active and InactiveRegions in the Drosophila Blastoderm (open access)

Transcription Factors Bind Thousands of Active and InactiveRegions in the Drosophila Blastoderm

Identifying the genomic regions bound by sequence-specific regulatory factors is central both to deciphering the complex DNA cis-regulatory code that controls transcription in metazoans and to determining the range of genes that shape animal morphogenesis. Here, we use whole-genome tiling arrays to map sequences bound in Drosophila melanogaster embryos by the six maternal and gap transcription factors that initiate anterior-posterior patterning. We find that these sequence-specific DNA binding proteins bind with quantitatively different specificities to highly overlapping sets of several thousand genomic regions in blastoderm embryos. Specific high- and moderate-affinity in vitro recognition sequences for each factor are enriched in bound regions. This enrichment, however, is not sufficient to explain the pattern of binding in vivo and varies in a context-dependent manner, demonstrating that higher-order rules must govern targeting of transcription factors. The more highly bound regions include all of the over forty well-characterized enhancers known to respond to these factors as well as several hundred putative new cis-regulatory modules clustered near developmental regulators and other genes with patterned expression at this stage of embryogenesis. The new targets include most of the microRNAs (miRNAs) transcribed in the blastoderm, as well as all major zygotically transcribed dorsal-ventral patterning genes, whose expression …
Date: January 10, 2008
Creator: Li, Xiao-Yong; MacArthur, Stewart; Bourgon, Richard; Nix, David; Pollard, Daniel A.; Iyer, Venky N. et al.
System: The UNT Digital Library
Comparison of multiple ecogenomics methods for determining ecosystem function in uranium-contaminated environments (open access)

Comparison of multiple ecogenomics methods for determining ecosystem function in uranium-contaminated environments

Background: Bioremediation may offer the only feasiblestrategy for the nearly intractable problem of metal and radionuclidecontamination of soil and groundwater. To understand bioremediation incontaminated environments, it is critical to determine the organismspresent in these environments, analyze their responses to stressconditions, and elucidate functional position in the environment.Methods: We used multiple molecular techniques on both sediment andgroundwater to develop a better understanding of the functionalcapability and stress level within the microbial community inrelationship to over one hundred geochemical parameters. Due to the lowpH (3.5-4.5) and high contaminant levels (e.g., uranium) microbialdensities and activities were low. We used a phage polymeraseamplification system to construct large and small insert DNA libraries,performed metagenome sequencing, constructed clonal libraries of selectfunctional genes (SSU rRNA gene, nirK, nirS, amoA, pmoA, and dsrAB), useda SSU rDNA Phylochip microarray (9,000 taxa), and a functional gene array(23K genes). A complete comparison for community differences andsimilarities between the different techniques was assessed using severalbioinformatics techniques. Results: SSU rDNA analysis revealed thepresence of distinct bacterial phyla, including proteobacteria,acidobacteria, and planctomycetes along the contaminant gradient.Metagenome analysis identified many of the same organisms, and diversitywas lower in water than sediment. Analysis with functional gene arrays,phylochip, and specific probes for genes and organisms involved inbiogeochemical …
Date: January 10, 2007
Creator: Hazen, T. C.; Dehal, P.; Arkin, A. P.; Fields, M. W.; Keller, M.; Zhou, J. et al.
System: The UNT Digital Library
Thermal analysis of a helium-cooled, tube-bank blanket module for a tandem-mirror fusion reactor (open access)

Thermal analysis of a helium-cooled, tube-bank blanket module for a tandem-mirror fusion reactor

A blanket module concept for the central cell of a tandem mirror reactor is described which takes advantage of the excellent heat transfer and low pressure drop characteristics of tube banks in cross-flow. The blanket employs solid Li/sub 2/O as the tritium breeding material and helium as the coolant. The lithium oxide is contained in tubes arranged within the submodules as a two-pass, cross-flow heat exchanger. Primarily, the heat transfer and thermal-hydraulic aspects of the blanket design study are described in this paper. In particular, the analytical model used for selection of the best tube-bank design parameters is discussed in some detail.
Date: January 10, 1983
Creator: Werner, R. W.; Hoffman, M. A. & Johnson, G. L.
System: The UNT Digital Library
The future of defense and technology (open access)

The future of defense and technology

This document provides an insight into the future of national defense and the impacts of utilizing technology for improved defensive postures. (FI)
Date: January 10, 1991
Creator: Teller, E.
System: The UNT Digital Library
Analysis of electron heat transport in femtosecond laser-plasma interactions with layered solid targets and with thin foils (open access)

Analysis of electron heat transport in femtosecond laser-plasma interactions with layered solid targets and with thin foils

We analyze two types of experiments that enhance our knowledge of the electron heat transport in femtosecond laser produced plasmas. The first involves layered targets and the fall off of substrate signal with increasing overlayer thickness. The experiment uncertainties are too large at present to definitively quantify the heat transport. The second involves the radiative output from thin foils. The behavior of the spectral response to foil thickness implies that our understanding of the transport within the foils is quite good. 12 refs., 11 figs.
Date: January 10, 1991
Creator: Rosen, Mordecai D.
System: The UNT Digital Library
Sub-nanosecond cinematography in laser fusion research: current techniques and applications at the Lawrence Livermore National Laboratory (open access)

Sub-nanosecond cinematography in laser fusion research: current techniques and applications at the Lawrence Livermore National Laboratory

Progress in laser fusion research has increased the need for detail and precision in the diagnosis of experiments. This has spawned the development and use of sophisticated sub-nanosecond resolution diagnostic systems. These systems typically use ultrafast x-ray or optical streak cameras in combination with spatially imaging or spectrally dispersing elements. These instruments provide high resolution data essential for understanding the processes occurring in the interaction of high intensity laser light with targets. Several of these types of instruments and their capabilities will be discussed. The utilization of these kinds of diagnostics systems on the nearly completed 100 kJ Nova laser facility will be described.
Date: January 10, 1985
Creator: Coleman, L.W.
System: The UNT Digital Library
The Role of a Detailed Configuration Accounting (DCA) Atomic Physics Package in Explaing the Energy Balance in Ignition Scale Hohlraums (open access)

The Role of a Detailed Configuration Accounting (DCA) Atomic Physics Package in Explaing the Energy Balance in Ignition Scale Hohlraums

None
Date: January 10, 2011
Creator: Rosen, M; Scott, H; Hinkel, D; Williams, E; Callahan, D; Town, R et al.
System: The UNT Digital Library
Physics of Radiation-driven Islands Near the Tokamak Density Limit (open access)

Physics of Radiation-driven Islands Near the Tokamak Density Limit

In previous work [1], the onset criterion for radiation driven islands [2] in combination with a simple cylindrical model of tokamak current channel behavior was shown to be consistent with the empirical scaling of the tokamak density limit [3]. A number of the unexplained phenomena at the density limit are consistent with this novel physics mechanism. In this work, a more formal theoretical underpinning, consistent with cylindrical tearing mode theory, is developed for the onset criteria of these modes. The appropriate derivation of the radiation-driven addition to the modified Rutherford equation is discussed. Additionally, the ordering of the terms in the MRE is examined in a regime near the density limit. It is hoped that given the apparent success of this simple model in explaining the observed global scalings will lead to a more comprehensive analysis of the possibility that radiation driven islands are the physics mechanism responsible for the density limit. In particular, with modern diagnostic capabilities detailed measurements of current densities, electron densities and impurity concentrations at rational surfaces should be possible, enabling verification of the concepts described above.
Date: January 10, 2013
Creator: D.A. Gates, L. Delgado-Apricio and R.B. White
System: The UNT Digital Library
Dark Shadows (open access)

Dark Shadows

The U.S. Department of Energy's National Renewable Energy Laboratory, Sandia National Laboratories, the Solar Electric Power Association, the Utility Wind Integration Group, and the U.S. Department of Energy hosted a day-long public workshop on the variability of photovoltaic (PV) plants. The workshop brought together utilities, PV system developers, power system operators, and several experts to discuss the potential impacts of PV variability and uncertainty on power system operations.
Date: January 10, 2011
Creator: Mills, Andrew; Ahlstrom, Mark; Brower, Michael; Ellis, Abraham; George, Ray; Hoff, Tom et al.
System: The UNT Digital Library
An Initial Evaluation Of Characterization And Closure Options For Underground Pipelines Within A Hanford Site Single-Shell Tank Farm (open access)

An Initial Evaluation Of Characterization And Closure Options For Underground Pipelines Within A Hanford Site Single-Shell Tank Farm

The Hanford Site includes 149 single-shell tanks, organized in 12 'tank farms,' with contents managed as high-level mixed waste. The Hanford Federal Facility Agreement and Consent Order requires that one tank farm, the Waste Management Area C, be closed by June 30, 2019. A challenge to this project is the disposition and closure of Waste Management Area C underground pipelines. Waste Management Area C contains nearly seven miles of pipelines and 200 separate pipe segments. The pipelines were taken out of service decades ago and contain unknown volumes and concentrations of tank waste residuals from past operations. To understand the scope of activities that may be required for these pipelines, an evaluation was performed. The purpose of the evaluation was to identify what, if any, characterization methods and/or closure actions may be implemented at Waste Management Area C for closure of Waste Management Area C by 2019. Physical and analytical data do not exist for Waste Management Area C pipeline waste residuals. To develop estimates of residual volumes and inventories of contamination, an extensive search of available information on pipelines was conducted. The search included evaluating historical operation and occurrence records, physical attributes, schematics and drawings, and contaminant inventories associated …
Date: January 10, 2013
Creator: Badden, Janet W.; Connelly, Michael P.; Seeley, Paul N. & Hendrickson, Michelle L.
System: The UNT Digital Library
CEMENTITIOUS GROUT FOR CLOSING SRS HIGH LEVEL WASTE TANKS - #12315 (open access)

CEMENTITIOUS GROUT FOR CLOSING SRS HIGH LEVEL WASTE TANKS - #12315

In 1997, the first two United States Department of Energy (US DOE) high level waste tanks (Tanks 17-F and 20-F: Type IV, single shell tanks) were taken out of service (permanently closed) at the Savannah River Site (SRS). In 2012, the DOE plans to remove from service two additional Savannah River Site (SRS) Type IV high-level waste tanks, Tanks 18-F and 19-F. These tanks were constructed in the late 1950's and received low-heat waste and do not contain cooling coils. Operational closure of Tanks 18-F and 19-F is intended to be consistent with the applicable requirements of the Resource Conservation and Recovery Act (RCRA) and the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) and will be performed in accordance with South Carolina Department of Health and Environmental Control (SCDHEC). The closure will physically stabilize two 4.92E+04 cubic meter (1.3 E+06 gallon) carbon steel tanks and isolate and stabilize any residual contaminants left in the tanks. The closure will also fill, physically stabilize and isolate ancillary equipment abandoned in the tanks. A Performance Assessment (PA) has been developed to assess the long-term fate and transport of residual contamination in the environment resulting from the operational closure of the F-Area Tank …
Date: January 10, 2012
Creator: Langton, C.; Burns, H. & Stefanko, D.
System: The UNT Digital Library
Actinic characterization of EUV bump-type phase defects (open access)

Actinic characterization of EUV bump-type phase defects

Despite tremendous progress and learning with EUV lithography, quantitative experimental information about the severity of point-like phase defects remains in short supply. We present a study of measured, EUV aerial images from a series of well-characterized, open-field, bump-type programmed phase defects, created on a substrate before multilayer deposition.
Date: January 10, 2011
Creator: Goldberg, Kenneth A.; Mochi, Iacopo & Liang, Ted
System: The UNT Digital Library
Improvement of snowpack simulations in a regional climate model (open access)

Improvement of snowpack simulations in a regional climate model

To improve simulations of regional-scale snow processes and related cold-season hydroclimate, the Community Land Model version 3 (CLM3), developed by the National Center for Atmospheric Research (NCAR), was coupled with the Pennsylvania State University/NCAR fifth-generation Mesoscale Model (MM5). CLM3 physically describes the mass and heat transfer within the snowpack using five snow layers that include liquid water and solid ice. The coupled MM5–CLM3 model performance was evaluated for the snowmelt season in the Columbia River Basin in the Pacific Northwestern United States using gridded temperature and precipitation observations, along with station observations. The results from MM5–CLM3 show a significant improvement in the SWE simulation, which has been underestimated in the original version of MM5 coupled with the Noah land-surface model. One important cause for the underestimated SWE in Noah is its unrealistic land-surface structure configuration where vegetation, snow and the topsoil layer are blended when snow is present. This study demonstrates the importance of the sheltering effects of the forest canopy on snow surface energy budgets, which is included in CLM3. Such effects are further seen in the simulations of surface air temperature and precipitation in regional weather and climate models such as MM5. In addition, the snow-season surface albedo …
Date: January 10, 2011
Creator: Jin, J. & Miller, N. L.
System: The UNT Digital Library
Element-specific study of epitaxial NiO/Ag/CoO/Fe films grown on vicinal Ag(001) using photoemission electron microscopy (open access)

Element-specific study of epitaxial NiO/Ag/CoO/Fe films grown on vicinal Ag(001) using photoemission electron microscopy

NiO/Ag/CoO/Fe single crystalline films are grown epitaxially on a vicinal Ag(001) substrate using molecular beam epitaxy and investigated by photoemission electron microscopy. We find that after zero-field cooling, the in-plane Fe magnetization switches from parallel to perpendicular direction of the atomic steps of the vicinal surface at thinner CoO thickness but remains in its original direction parallel to the steps at thicker CoO thickness. CoO and NiO domain imaging result shows that both CoO/Fe and NiO/CoO spins are perpendicularly coupled, suggesting that the Fe magnetization switching may be associated with the rotatable-frozen spin transition of the CoO film.
Date: January 10, 2011
Creator: Meng, Y.; Li, J.; Tan, A.; Jin, E.; Son, J.; Park, J. S. et al.
System: The UNT Digital Library