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The 2019 materials by design roadmap (open access)

The 2019 materials by design roadmap

This roadmap article presents an overview of the current state of computational materials prediction, synthesis and characterization approaches, materials design needs for various technologies, and future challenges and opportunities that must be addressed.
Date: October 24, 2018
Creator: Alberi, Kirstin; Buongiorno Nardelli, Marco; Zakutayev, Andriy; Mitas, Lubos; Curtarolo, Stefano; Jain, Anubhav et al.
System: The UNT Digital Library
Accelerator Physics Code Web Repository (open access)

Accelerator Physics Code Web Repository

In the framework of the CARE HHH European Network, we have developed a web-based dynamic accelerator-physics code repository. We describe the design, structure and contents of this repository, illustrate its usage, and discuss our future plans, with emphasis on code benchmarking.
Date: October 24, 2006
Creator: Zimmermann, F.; Basset, R.; Bellodi, G.; Benedetto, E.; Dorda, U.; Giovannozzi, M. et al.
System: The UNT Digital Library
Accelerators, Beams And Physical Review Special Topics - Accelerators And Beams (open access)

Accelerators, Beams And Physical Review Special Topics - Accelerators And Beams

Accelerator science and technology have evolved as accelerators became larger and important to a broad range of science. Physical Review Special Topics - Accelerators and Beams was established to serve the accelerator community as a timely, widely circulated, international journal covering the full breadth of accelerators and beams. The history of the journal and the innovations associated with it are reviewed.
Date: October 24, 2011
Creator: Siemann, R. H.
System: The UNT Digital Library
An acoustic analysis of American English liquids by adults and children: Native English speakers and native Japanese speakers of English (open access)

An acoustic analysis of American English liquids by adults and children: Native English speakers and native Japanese speakers of English

This article is a study investigating acoustic characteristics of American English liquids produced by native English (NE) and native Japanese (NJ) speakers reported in Aoyama, Flege, Guion, Akahane-Yamada, and Yamada [(2004). J. Phonetics 32, 233–250]. The secondary aim of the study is to compare the acoustic nature of English liquids between native speakers and Japanese L2 speakers of English. This work was presented at the 170th Meeting of the Acoustical Society of America on June 25, 2017 in Boston, MA.
Date: June 7, 2019
Creator: Aoyama, Katsura; Flege, James E.; Akahane-Yamada, Reiko & Yamada, Tsuneo
System: The UNT Digital Library
Advanced Transient Simulator for Studying Shallow Gas Blowouts (open access)

Advanced Transient Simulator for Studying Shallow Gas Blowouts

None
Date: October 24, 2000
Creator: RATH,JONATHAN S. & PODIO,AUGUSTO L.
System: The UNT Digital Library
Aerosol research at Hanford and engineering applications to production reactors (open access)

Aerosol research at Hanford and engineering applications to production reactors

When the construction of the confinement facilities for Hanford production reactors is completed, the potential for contaminating the environment with accidentally released fission products will be greatly reduced. This was demonstrated already when rupture debris burned in the rear face area of one of the reactors in which the fog spray was installed and ready for service. The fog spray effectively prevented the spread of contamination to the ventilation equipment downstream of the rear face enclosure. Also, the commercially- available absolute filters and charcoal beds will significantly decontaminate the exhaust air, stream of all fission products except the noble gases. Laboratory studies indicate that the filter system should remove at least 50 percent of all fission product halogen vapors and over 90 percent of the particulate matter released from a nuclear incident. In addition, the charcoal beds should provide an additional 90 to 95 percent decontamination of the halogens that manage to pass through the filter. It is not expected that any of the noble gases released will be removed by this system. Laboratory studies, in general, substantiate previous estimates on the release of fission products from overheated uranium fuels. The theoretical estimates are quite accurate for the volatile and …
Date: October 24, 1960
Creator: Linderoth, C. E.; Heacock, H. W. & Schwendiman, L. C.
System: The UNT Digital Library
Analysis of dense pusher laser-driven implosions for intermediate densities (open access)

Analysis of dense pusher laser-driven implosions for intermediate densities

Post-shot analysis of targets designed to achieve a diagnosible compression of DT gas to 2. g/cm/sup 3/ or 10 x liquid density is reported. The SHIVA laser provided 15 to 20 TW of 1.06 ..mu..m laser light. Detailed comparisons of diagnostic results with hydro-code calculations are made. Implications for laser light absorption/scattering, thermal conduction, suprathermal electron preheat, implosion symmetry, and pusher-fuel mix are discussed. Uncertainties of the density determination methods are analyzed. Good overall consistency is found, indicating strong support for the successful attainment of 1.-3. g/cm/sup 3/.
Date: October 24, 1979
Creator: Mead, W. C.; Orth, C. D.; Bailey, D. S.; McClellan, G. & Estabrook, K. G.
System: The UNT Digital Library
Aperture-based antihydrogen gravity experiment: Parallel plate geometry (open access)

Aperture-based antihydrogen gravity experiment: Parallel plate geometry

This article presents an analytical model and a Monte Carlo simulation of an experiment that could be used to determine the direction of the acceleration of antihydrogen due to gravity.
Date: October 24, 2013
Creator: Rocha, J. R.; Hedlof, R. M. & Ordonez, Carlos A.
System: The UNT Digital Library
Application of the BRF system to some superconducting magnet design problems (open access)

Application of the BRF system to some superconducting magnet design problems

None
Date: October 24, 1974
Creator: Meuser, R.B.
System: The UNT Digital Library
Association of Host and Microbial Species Diversity across Spatial Scales in Desert Rodent Communities (open access)

Association of Host and Microbial Species Diversity across Spatial Scales in Desert Rodent Communities

Article describes study in which researchers employed a natural gradient of rodent species richness and quantified bacterial communities in rodent blood at several hierarchical spatial scales to test the hypothesis that associations between host and microbial species diversity will be positive in communities dominated by organisms with broad niches sampled at large scales.
Date: October 24, 2014
Creator: Gavish, Yoni; Kedem, Hadar; Messika, Irit; Cohen, Carmit; Toh, Evelyn; Munro, Daniel et al.
System: The UNT Digital Library
Attempt to produce element 120 in the 244Pu + 58Fe reaction (open access)

Attempt to produce element 120 in the 244Pu + 58Fe reaction

An experiment aimed at the synthesis of isotopes of element 120 has been performed using the {sup 244}Pu({sup 58}Fe,xn){sup 302-x} 120 reaction. No decay chains consistent with fusion-evaporation reaction products were observed during an irradiation with a beam dose of 7.1 x 10{sup 18} 330-MeV {sup 58}Fe projectiles. The sensitivity of the experiment corresponds to a cross section of 0.4 pb for the detection of one decay.
Date: October 24, 2008
Creator: Oganessian, Y. T.; Utyonkov, V. K.; Lobanov, Y. V.; Abdullin, F. S.; Polyakov, A. N.; Sagaidak, R. N. et al.
System: The UNT Digital Library
Bessel-Zernike Discrete Variable Representation Basis (open access)

Bessel-Zernike Discrete Variable Representation Basis

The connection between the Bessel discrete variable basis expansion and a specific form of an orthogonal set of Jacobi polynomials is demonstrated. These so-called Zernike polynomials provide alternative series expansions of suitable functions over the unit interval. Expressing a Bessel function in a Zernike expansion provides a straightforward method of generating series identities. Furthermore, the Zernike polynomials may also be used to efficiently evaluate the Hankel transform for rapidly decaying functions or functions with finite support.
Date: October 24, 2005
Creator: Cerjan, C J
System: The UNT Digital Library
Building the World's Fastest Linux Cluster (open access)

Building the World's Fastest Linux Cluster

Imagine having 2,304 Xeon processors running day and night solving complex problems. With a theoretical peak of 11.2 teraflops, that is just what the MCR cluster at Lawrence Livermore National Labs (LLNL) is doing. Over the past several years, Lawrence Livermore National Laboratory has deployed a series of increasingly large and powerful Intel-based Linux clusters. The most significant of these is a cluster known as the MCR (Multiprogrammactic Capability Resource). With 1,152 Intel Xeon (2.4 GHz) dual-processor nodes from Linux NetworX and a high performance interconnect from Quadrics, LTD., the MCR currently ranks third on the 21st Top 500 Supercomputer Sites List and is the fastest Linux cluster in the world. This feat was accomplished with a total system cost (hardware including maintenance, in-reconnect, global file system storage) of under $14 million. Although production clusters like the MCR are still custom built supercomputers that require as much artistry as skill, the experiences of LLNL have helped clear an important path for other clusters to follow.
Date: October 24, 2003
Creator: Goldstone, R & Seager, M
System: The UNT Digital Library
Cantilever Epitaxy: A simple Lateral Growth Technique for Reducing Dislocation Densitites in GaN and Other Nitrides (open access)

Cantilever Epitaxy: A simple Lateral Growth Technique for Reducing Dislocation Densitites in GaN and Other Nitrides

None
Date: October 24, 2000
Creator: Ashby, Carol I.; Willan, Christine C.; Han, Jung; Missert, Nancy A.; Provencio, Paula P.; Follstaedt, David M. et al.
System: The UNT Digital Library
Celebrating 20 Years of Genetic Discoveries in Legume Nodulation and Symbiotic Nitrogen Fixation (open access)

Celebrating 20 Years of Genetic Discoveries in Legume Nodulation and Symbiotic Nitrogen Fixation

This article is a review cataloging and contextualizing all of the plant genes currently known to be required for SNF in two model legume species, Medicago truncatula and Lotus japonicus, and two crop species, Glycine max (soybean) and Phaseolus vulgaris (common bean). The authors also briefly consider the future of SNF genetics in the era of pan-genomics and genome editing.
Date: October 24, 2019
Creator: Roy, Sonali; Liu, Wei; Nandety, Raja Sekhar; Crook, Ashley; Mysore, Kirankumar S.; Pislariu, Catalina I. et al.
System: The UNT Digital Library
A Cell-Based Approach for the Biosynthesis/Screening of Cyclic Peptide Libraries against Bacterial Toxins (open access)

A Cell-Based Approach for the Biosynthesis/Screening of Cyclic Peptide Libraries against Bacterial Toxins

Available methods for developing and screening small drug-like molecules able to knockout toxins or pathogenic microorganisms have some limitations. In order to be useful, these new methods must provide high-throughput analysis and identify specific binders in a short period of time. To meet this need, we are developing an approach that uses living cells to generate libraries of small biomolecules, which are then screened inside the cell for activity. Our group is using this new, combined approach to find highly specific ligands capable of disabling anthrax Lethal Factor (LF) as proof of principle. Key to our approach is the development of a method for the biosynthesis of libraries of cyclic peptides, and an efficient screening process that can be carried out inside the cell.
Date: October 24, 2007
Creator: Camarero, J. A.; Kimura, R.; Woo, Y.; Cantor, J. & Steenblock, E.
System: The UNT Digital Library
Chemometric and Statistical Analyses of ToF-SIMS Spectra of Increasingly Complex Biological Samples (open access)

Chemometric and Statistical Analyses of ToF-SIMS Spectra of Increasingly Complex Biological Samples

Characterizing and classifying molecular variation within biological samples is critical for determining fundamental mechanisms of biological processes that will lead to new insights including improved disease understanding. Towards these ends, time-of-flight secondary ion mass spectrometry (ToF-SIMS) was used to examine increasingly complex samples of biological relevance, including monosaccharide isomers, pure proteins, complex protein mixtures, and mouse embryo tissues. The complex mass spectral data sets produced were analyzed using five common statistical and chemometric multivariate analysis techniques: principal component analysis (PCA), linear discriminant analysis (LDA), partial least squares discriminant analysis (PLSDA), soft independent modeling of class analogy (SIMCA), and decision tree analysis by recursive partitioning. PCA was found to be a valuable first step in multivariate analysis, providing insight both into the relative groupings of samples and into the molecular basis for those groupings. For the monosaccharides, pure proteins and protein mixture samples, all of LDA, PLSDA, and SIMCA were found to produce excellent classification given a sufficient number of compound variables calculated. For the mouse embryo tissues, however, SIMCA did not produce as accurate a classification. The decision tree analysis was found to be the least successful for all the data sets, providing neither as accurate a classification nor chemical …
Date: October 24, 2007
Creator: Berman, E. S.; Wu, L.; Fortson, S. L.; Nelson, D. O.; Kulp, K. S. & Wu, K. J.
System: The UNT Digital Library
(CN{sub 3}H{sub 6}){sub 2} {center_dot} Zn(HPO{sub 3}){sub 2}: A Three-Dimensional Framework Zincophosphite Containing Polyhedral 12-Rings (open access)

(CN{sub 3}H{sub 6}){sub 2} {center_dot} Zn(HPO{sub 3}){sub 2}: A Three-Dimensional Framework Zincophosphite Containing Polyhedral 12-Rings

The solution-mediated synthesis and single crystal structure of (CN{sub 3}H{sub 6}){sub 2} {center_dot} Zn(HPO{sub 3}){sub 2} are reported. This phase is built up from a three-dimensional framework of vertex-linked ZnO{sub 4} and HPO{sub 3} building units encapsulating the extra-framework guanidinium cations. The structure is stabilized by template-to-framework hydrogen bonding. The inorganic framework shows a surprising similarity to those of some known zinc phosphates. Crystal data: (CN{sub 3}H{sub 6}){sub 2} {center_dot} Zn(HPO{sub 3}){sub 2}, AI,= 345.50, orthorhombic, space group Fdd2 (No. 43), a = 15.2109 (6) {angstrom}, b = 11.7281 (5) {angstrom}, c = 14.1821 (6) {angstrom}, V = 2530.0 (4){angstrom}{sup 3}, Z = 8, T = 298 (2)K, R(F) = 0.020, wR(F) = 0.025.
Date: October 24, 2000
Creator: Harrison, William T. A.; Phillips, Mark L. F. & Nenoff, Tina M.
System: The UNT Digital Library
Consolidation of Modal Parameters from Several Extraction Sets (open access)

Consolidation of Modal Parameters from Several Extraction Sets

Experienced experimentalists have gone through the process of attempting to identify a final set of modal parameters from several different sets of extracted parameters. Usually, this is done by visually examining the mode shapes. With the advent of automated modal parameter extraction algorithms such as SMAC (Synthesize Modes and Correlate), very accurate extractions can be made to high frequencies. However, this process may generate several hundred modes that then must be consolidated into a final set of modal information. This has motivated the authors to generate a set of tools to speed the process of consolidating modal parameters by mathematical (instead of visual) means. These tools help quickly identify the best modal parameter extraction associated with several extractions of the same mode. The tools also indicate how many different modes have been extracted in a nominal frequency range and from which references. The mathematics are presented to achieve the best modal extraction of multiple modes at the same nominal frequency. Improvements in the SMAC graphical user interface and database are discussed that speed and improve the entire extraction process.
Date: October 24, 2000
Creator: MAYES,RANDALL L. & KLENKE,SCOTT E.
System: The UNT Digital Library
Constraining the leading weak axial two-body current by SNO and Super-K (open access)

Constraining the leading weak axial two-body current by SNO and Super-K

We analyze the Sudbury Neutrino Observatory (SNO) and Super-Kamiokande (SK) data on charged current (CC), neutral current (NC) and neutrino electron elastic scattering (ES) reactions to constrain the leading weak axial two-body current parameterized by L{sub 1A}. This two-body current is the dominant uncertainty of every low energy weak interaction deuteron breakup process, including SNO's CC and NC reactions. Our method shows that the theoretical inputs to SNO's determination of the CC and NC fluxes can be self-calibrated, be calibrated by SK, or be calibrated by reactor data. The only assumption made is that the total flux of active neutrinos has the standard {sup 8}B spectral shape (but distortions in the electron neutrino spectrum are allowed). We show that SNO's conclusion about the inconsistency of the no-flavor-conversion hypothesis does not contain significant theoretical uncertainty, and we determine the magnitude of the active solar neutrino flux.
Date: October 24, 2002
Creator: Chen, Jiunn-Wei; Heeger, Karsten M. & Robertson, R.G. Hamish
System: The UNT Digital Library
Cookoff response of PBXN-109: material characterization and ALE3D model (open access)

Cookoff response of PBXN-109: material characterization and ALE3D model

Materials properties measurements are made for the RDX-based explosive, PBXN-109, and an initial ALE3D model for cookoff is discussed. A significant effort is underway in the U.S. Navy and Department of Energy (DOE) laboratories to understand the thermal explosion behavior of this material. Benchmark cookoff experiments are being performed by the U.S. Navy to validate DOE materials models and computer codes. The ALE3D computer code can model the coupled thermal, mechanical, and chemical behavior of heating and ignition in cookoff tests. In order to provide a predictive capability, materials characterization measurements are being performed to specify parameters in these models. We report on progress in the development of these ALE3D materials models and present measurements as a function of temperature for thermal expansion, heat capacity, shear modulus, bulk modulus, and One-Dimensional-Time-to-Explosion (ODTX).
Date: October 24, 2000
Creator: McClelland, M A; Tran, T D; Cunningham, B J; Weese, R K & Maienschein, J L
System: The UNT Digital Library
Coulomb Excitation of the 242mAm Isomer (open access)

Coulomb Excitation of the 242mAm Isomer

The {sup 242m}Am isomer, a well-known candidate for photo-depopulation research, has been studied in this first ever Coulomb excitation of a nearly pure ({approx} 98%) isomer target. Thirty new states, including a new rotational band built on a K{sup {pi}} = 6{sup -} state have been identified. Strong K-mixing results in nearly equal populations of the K{sup {pi}} = 5{sup -} and 6{sup -} states. Newly identified states have been assigned to the K{sup {pi}} = 3{sup -} rotational band, the lowest states of which are known to decay into the ground-state band. Implications regarding K-mixing and Coulomb excitation paths to the ground state are discussed.
Date: October 24, 2006
Creator: Hayes, A. B.; Cline, D.; Moody, K. J.; Wu, C. Y.; Becker, J. A.; Carpenter, M. P. et al.
System: The UNT Digital Library
Crystal structure of kappa-In2Se3 (open access)

Crystal structure of kappa-In2Se3

Structural properties of single-phase films of {kappa}-In{sub 2}Se{sub 3} and {gamma}-In{sub 2}Se{sub 3} were investigated. Both films were polycrystalline but their microstructure differed considerably. The a-lattice parameter of {kappa}-In{sub 2}Se{sub 3} has been measured. Comparison between these two materials indicates that {kappa}-In{sub 2}Se{sub 3} has a significantly larger unit cell ({Delta}c = 2.5 {+-} 0.2 % and {Delta}a = 13.5 {+-} 0.5%) and a structure more similar to the {alpha}-phase of In{sub 2}Se{sub 3}.
Date: October 24, 2002
Creator: Jasinski, J.; Swider, W.; Washburn, J.; Liliental-Weber, Z.; Chaiken, A.; Nauka, K. et al.
System: The UNT Digital Library
Current Advances in the Computational Simulation of the Formation of Low-Mass Stars (open access)

Current Advances in the Computational Simulation of the Formation of Low-Mass Stars

Developing a theory of low-mass star formation ({approx} 0.1 to 3 M{sub {circle_dot}}) remains one of the most elusive and important goals of theoretical astrophysics. The star-formation process is the outcome of the complex dynamics of interstellar gas involving non-linear interactions of turbulence, gravity, magnetic field and radiation. The evolution of protostellar condensations, from the moment they are assembled by turbulent flows to the time they reach stellar densities, spans an enormous range of scales, resulting in a major computational challenge for simulations. Since the previous Protostars and Planets conference, dramatic advances in the development of new numerical algorithmic techniques have been successfully implemented on large scale parallel supercomputers. Among such techniques, Adaptive Mesh Refinement and Smooth Particle Hydrodynamics have provided frameworks to simulate the process of low-mass star formation with a very large dynamic range. It is now feasible to explore the turbulent fragmentation of molecular clouds and the gravitational collapse of cores into stars self-consistently within the same calculation. The increased sophistication of these powerful methods comes with substantial caveats associated with the use of the techniques and the interpretation of the numerical results. In this review, we examine what has been accomplished in the field and present …
Date: October 24, 2005
Creator: Klein, R. I.; Inutsuka, S.; Padoan, P. & Tomisaka, K.
System: The UNT Digital Library