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Advances in lithium-ion batteries (open access)

Advances in lithium-ion batteries

The editors state in their introduction that this book is intended for lithium-ion scientists and engineers but they hope it may be of interest to scientists from other fields. Their main aim was to provide a snapshot of the state of the Lithium-ion art and in this they have largely succeeded. The book is comprised of a collection of very current reviews of the lithium ion battery literature by acknowledged experts that draw heavily on the authors' own research but are sufficiently general to provide the lithium ion researcher with enough guidance to the current literature and the current thinking in the field. Some of the literature references may be too current as there are numerous citations of conference proceedings which may be easily accessible to the lithium ion scientist or engineer but are not likely to be available to the interested chemist coming to the field for the first time. One author expresses the hope and expectation that properly peer-reviewed articles will appear in due course and the interested reader should look out for them in future. From the point of view of the lithium ion battery scientist and engineer, the book covers most of the topics that are …
Date: June 24, 2003
Creator: Kerr, John B.
System: The UNT Digital Library
Air filtration enhancement using electronic techniques (open access)

Air filtration enhancement using electronic techniques

Dielectrophoretic filtration experiments were conducted on glass, polyester, dacron, Teflon, wool, acrylic and polypropylene filter media. A polydispersed (sigma g = 2.0, ammd = 0.95 ..mu.. m) sodium chloride particle was used as a test aerosol. All materials exhibited significant increases in efficiency with increasing field strengths. Efficiencies of greater than 99 percent could be obtained from glass fiber mats using a 13 kV/cm electric field at 16.3 cm/s face velocity.
Date: June 24, 1976
Creator: Nelson, G. O.; Richards, C. P.; Biermann, A. H.; Taylor, R. D. & Miller, H. H.
System: The UNT Digital Library
Analog Amplitude Modulation of a High Voltage, Solid State Inductive Adder, Pulse Generator Using MOSFETS (open access)

Analog Amplitude Modulation of a High Voltage, Solid State Inductive Adder, Pulse Generator Using MOSFETS

High voltage, solid state, inductive adder, pulse generators have found increasing application as fast kicker pulse modulators for charged particle beams. The solid state, inductive adder, pulse generator is similar in operation to the linear induction accelerator. The main difference is that the solid state, adder couples energy by transformer action from multiple primaries to a voltage summing stalk, instead of an electron beam. Ideally, the inductive adder produces a rectangular voltage pulse at the load. In reality, there is usually some voltage variation at the load due to droop on primary circuit storage capacitors, or, temporal variations in the load impedance. Power MOSFET circuits have been developed to provide analog modulation of the output voltage amplitude of a solid state, inductive adder, pulse generator. The modulation is achieved by including MOSFET based, variable subtraction circuits in the multiple primary stack. The subtraction circuits can be used to compensate for voltage droop, or, to tailor the output pulse amplitude to provide a desired effect in the load. Power MOSFET subtraction circuits have been developed to modulate short, temporal (60-400 ns), voltage and current pulses. MOSFET devices have been tested up to 20 amps and 800 Volts with a band pass …
Date: June 24, 2002
Creator: Gower, E J & Sullivan, J S
System: The UNT Digital Library
Anisotropic Magnetism in Field-Structured Composites (open access)

Anisotropic Magnetism in Field-Structured Composites

Magnetic field-structured-composites (FSCs) are made by structuring magnetic particle suspensions in uniaxial or biaxial (e.g. rotating) magnetic fields, while polymerizing the suspending resin. A uniaxial field produces chain-like particle structures, and a biaxial field produces sheet-like particle structures. In either case, these anisotropic structures affect the measured magnetic hysteresis loops, with the magnetic remanence and susceptibility increased significantly along the axis of the structuring field, and decreased slightly orthogonal to the structuring field, relative to the unstructured particle composite. The coercivity is essentially unaffected by structuring. We present data for FSCs of magnetically soft particles, and demonstrate that the altered magnetism can be accounted for by considering the large local fields that occur in FSCs. FSCS of magnetically hard particles show unexpectedly large anisotropies in the remanence, and this is due to the local field effects in combination with the large crystalline anisotropy of this material.
Date: June 24, 1999
Creator: Anderson, Robert A.; Martin, James E.; Odinek, Judy & Venturini, Eugene
System: The UNT Digital Library
ANS-8. 23: Criticality accident emergency planning and response (open access)

ANS-8. 23: Criticality accident emergency planning and response

A study group has been formed under the auspices of ANS-8 to examine the need for a standard on nuclear criticality accident emergency planning and response. This standard would be ANS-8.23. ANSI/ANS-8.19-1984, Administrative Practices for Nuclear Criticality Safety, provides some guidance on the subject in Section 10 titled -- Planned Response to Nuclear Criticality Accidents. However, the study group has formed a consensus that Section 10 is inadequate in that technical guidance in addition to administrative guidance is needed. The group believes that a new standard which specifically addresses emergency planning and response to a perceived criticality accident is needed. Plans for underway to request the study group be designated a writing group to create a draft of such a new standard. The proposed standard will divide responsibility between management and technical staff. Generally, management will be charged with providing the necessary elements of emergency planning such as a criticality detection and alarm system, training, safe evacuation routes and assembly areas, a system for timely accountability of personnel, and an effective emergency response organization. The technical staff, on the other hand, will be made responsible for establishing specific items such as safe and clearly posted evacuation evacuation routes and dose …
Date: June 24, 1991
Creator: Pruvost, Norman L.
System: The UNT Digital Library
Assembling the Marine Metagenome, One Cell at a Time (open access)

Assembling the Marine Metagenome, One Cell at a Time

The difficulty associated with the cultivation of most microorganisms and the complexity of natural microbial assemblages, such as marine plankton or human microbiome, hinder genome reconstruction of representative taxa using cultivation or metagenomic approaches. Here we used an alternative, single cell sequencing approach to obtain high-quality genome assemblies of two uncultured, numerically significant marine microorganisms. We employed fluorescence-activated cell sorting and multiple displacement amplification to obtain hundreds of micrograms of genomic DNA from individual, uncultured cells of two marine flavobacteria from the Gulf of Maine that were phylogenetically distant from existing cultured strains. Shotgun sequencing and genome finishing yielded 1.9 Mbp in 17 contigs and 1.5 Mbp in 21 contigs for the two flavobacteria, with estimated genome recoveries of about 91percent and 78percent, respectively. Only 0.24percent of the assembling sequences were contaminants and were removed from further analysis using rigorous quality control. In contrast to all cultured strains of marine flavobacteria, the two single cell genomes were excellent Global Ocean Sampling (GOS) metagenome fragment recruiters, demonstrating their numerical significance in the ocean. The geographic distribution of GOS recruits along the Northwest Atlantic coast coincided with ocean surface currents. Metabolic reconstruction indicated diverse potential energy sources, including biopolymer degradation, proteorhodopsin photometabolism, …
Date: June 24, 2010
Creator: Woyke, Tanja; Xie, Gary; Copeland, Alex; Gonzalez, Jose M.; Han, Cliff; Kiss, Hajnalka et al.
System: The UNT Digital Library
Atomic structure of the {sigma}5 (210)/[001] symmetric tilt grain boundary in yttrium aluminum garnet (open access)

Atomic structure of the {sigma}5 (210)/[001] symmetric tilt grain boundary in yttrium aluminum garnet

The {Sigma}5(210)/[100] symmetric tilt grain boundary in YAG was produced by UHV diffusion bonding precisely oriented single crystals. The boundary has been characterized by HREM along two different directions, parallel and perpendicular to the tilt axis. Models of the atomic structure of the boundary were formed following the Coincident Site Lattice scheme. The resulting models are equivalent to twins formed at the atomic scale. The high resolution images show no rigid crystal translations away from the perfect mirror reflection relation. Comparison of the simulated images using the atomic model as input with the experimental images identifies the plane of mirror symmetry. The atomic model is shown to be in good agreement with the experimental images when viewed parallel to tilt axis, but disagrees with the images perpendicular to tilt axis. Agreement between simulated and experimental images can be improved by changing the composition of the grain boundary with respect to the bulk. To reach a more certain conclusion on the structure of the grain boundary will require additional theoretical calculations.
Date: June 24, 1996
Creator: Campbell, G. H. & King, W. E.
System: The UNT Digital Library
Beam Ion Instability in SPEAR3: Measurements, Analyses and Simulations (open access)

Beam Ion Instability in SPEAR3: Measurements, Analyses and Simulations

None
Date: June 24, 2013
Creator: Wang, L.; Safranek, J.; Cai, Y.; Corbett, J.; Hettel, B.; Raubenheimer, T.O. et al.
System: The UNT Digital Library
A Binary Segmentation Approach for Boxing Ribosome Particles in Cryo EM Micrographs (open access)

A Binary Segmentation Approach for Boxing Ribosome Particles in Cryo EM Micrographs

Three-dimensional reconstruction of ribosome particles from electron micrographs requires selection of many single-particle images. Roughly 100,000 particles are required to achieve approximately 10 angstrom resolution. Manual selection of particles, by visual observation of the micrographs on a computer screen, is recognized as a bottleneck in automated single particle reconstruction. This paper describes an efficient approach for automated boxing of ribosome particles in micrographs. Use of a fast, anisotropic non-linear reaction-diffusion method to pre-process micrographs and rank-leveling to enhance the contrast between particles and the background, followed by binary and morphological segmentation constitute the core of this technique. Modifying the shape of the particles to facilitate segmentation of individual particles within clusters and boxing the isolated particles is successfully attempted. Tests on a limited number of micrographs have shown that over 80 percent success is achieved in automatic particle picking.
Date: June 24, 2003
Creator: Adiga, Umesh P. S.; Malladi, Ravi; Baxter, William & Glaeser, Robert M.
System: The UNT Digital Library
Bunch Length Measurements using Coherent Radiation (open access)

Bunch Length Measurements using Coherent Radiation

The accelerating field that can be obtained in a beam-driven plasma wakefield accelerator depends on the current of the electron beam that excites the wake. In the E-167 experiment, a peak current above 10 kA will be delivered at a particle energy of 28 GeV. The bunch has a length of a few ten micrometers and several methods are used to measure its longitudinal profile. Among these, autocorrelation of coherent transition radiation (CTR) is employed. The beam passes a thin metallic foil, where it emits transition radiation. For wavelengths greater than the bunch length, this transition radiation is emitted coherently. This amplifies the long-wavelength part of the spectrum. A scanning Michelson interferometer is used to autocorrelate the CTR. However, this method requires the contribution of many bunches to build an autocorrelation trace. The measurement is influenced by the transmission characteristics of the vacuum window and beam splitter. We present here an analysis of materials, as well as possible layouts for a single shot CTR autocorrelator.
Date: June 24, 2005
Creator: Ischebeck, Rasmus; Barnes, Christopher; Blumenfeld, Ian; Decker, Franz-Josef; Hogan, Mark; Iverson, Richard H. et al.
System: The UNT Digital Library
Can cross sections be accurately known for priori? (open access)

Can cross sections be accurately known for priori?

Distinct maxima and minima in the neutron total cross section uncertainties were observed in our large scale covariance calculations using a spherical optical potential. In this contribution we investigate the physical origin of this oscillating structure. Specifically, we analyze the case of neutron reactions on {sup 56}Fe, for which total cross section uncertainties are characterized by the presence of five distinct minima at 0.1, 1.1, 5, 25, and 70 MeV. To investigate their origin, we calculated total cross sections by perturbing the real volume depth V{sub v} by its expected uncertainty {+-}{Delta}V{sub v}. Inspecting the effect of this perturbation on the partial wave cross sections we found that the first minimum (at 0.1 MeV) is exclusively due to the contribution of the s-wave. On the other hand, the same analysis at 1.1 MeV showed that the minimum is the result of the interplay between s-, p-, and d-waves; namely the change in the s-wave happens to be counterbalanced by changes in the p- and d-waves. Similar considerations can be extended for the third minimum, although it can be also explained in terms of the Ramsauer effect as well as the other ones (at 25 and 70 MeV). We discuss the …
Date: June 24, 2008
Creator: Pigni, M. T.; Dietrich, F. S.; Herman, M. & Oblozinsky, P.
System: The UNT Digital Library
Cardiorespiratory physiological phenotypic plasticity in developing air-breathing anabantid fishes (Betta splendens and Trichopodus trichopterus) (open access)

Cardiorespiratory physiological phenotypic plasticity in developing air-breathing anabantid fishes (Betta splendens and Trichopodus trichopterus)

This article discusses development plasticity of cardiorespiratory physiology in two air-breathing anabantid fishes.
Date: June 16, 2017
Creator: Mendez-Sanchez, Jose F. & Burggren, Warren W.
System: The UNT Digital Library
The Chandra Deep Field-South Survey: 7 Ms Source Catalogs (open access)

The Chandra Deep Field-South Survey: 7 Ms Source Catalogs

This article presents X-ray source catalogs for the ≈7 Ms exposure of the Chandra Deep Field-South (CF-S), which covers a total area of 484.2 arcmin².
Date: June 24, 2016
Creator: Luo, Bin; Brandt, William Nielsen; Xue, Yongquan; Lehmer, Bret; Alexander, David M.; Bauer, Franz E. et al.
System: The UNT Digital Library
Closure of the condensed-phase organic-nitrate reaction USQ at hanford (open access)

Closure of the condensed-phase organic-nitrate reaction USQ at hanford

A discovery Unreviewed Safety Question (USQ) was declared on the underground waste storage tanks at the Hanford Site in May 1996. The USQ was for condensed-phase organic-nitrate reactions (sometimes called organic complexant reactions) in the tanks. This paper outlines the steps taken to close the USQ, and resolve the related safety issue. Several processes were used at the Hanford Site to extract and/or process plutonium. These processes resulted in organic complexants (for chelating multivalent cations) and organic extraction solvents being sent to the underground waste storage tanks. This paper addresses the organic complexant hazard. The organic complexants are in waste matrices that include inert material, diluents, and potential oxidizers. In the presence of oxidizing material, the complexant salts can be made to react exothermically by heating to high temperatures or by applying an external ignition source of sufficient energy. The first organic complexant hazard assessments focused on determining whether a hulk runaway reaction could occur, similar to the 1957 accident at Kyshtm (a reprocessing plant in the former U.S.S.R.). Early analyses (1977 through 1994) examined organic-nitrate reaction onset temperatures and concluded that a bulk runaway reaction could not occur at the Hanford Site because tank temperatures were well below that …
Date: June 24, 1999
Creator: COWLEY, W.L.
System: The UNT Digital Library
Compatibility of the Radiating Divertor with High Performance Plasmas in DIII-D (open access)

Compatibility of the Radiating Divertor with High Performance Plasmas in DIII-D

Excessive thermal power loading on the divertor structures presents a design difficulty for future-generation, high powered tokamaks. This difficulty may be mitigated by ''seeding'' the divertor with impurities which radiate a significant fraction of the power upstream of the divertor targets. For this ''radiating divertor'' concept to be practical, however, the confinement and stability of the plasma cannot be compromised by excessive leakage of the seeded impurities into the core plasma. One proposed way of reducing impurity influx is to enhance the directed scrape-off layer (SOL) flow of deuterium ions toward the divertor [1-5]. We report here on the successful application of the radiating divertor scenario to high performance plasma operation in a DIII-D ''hybrid'' H-mode regime. The ''hybrid'' regime [6,7] has many features in common with conventional ELMing H-mode regimes, such as high confinement, e.g., H{sub ITER89P} > 2, where H{sub ITER89P} is the energy confinement normalized to the 1989 ITER L-mode scaling [8]. The main difference is the absence of sawtooth activity in the hybrid. Argon was selected as the seeded impurity for this experiment because argon radiates effectively at both the divertor and pedestal temperatures found in DIII-D hybrid H-mode operation and has a relatively short ionization …
Date: June 24, 2005
Creator: Petrie, T; Wade, M; Allen, S; Brooks, N; Fenstermacher, M; Ferron, J et al.
System: The UNT Digital Library
Comprehensive Measurements and Modeling of SOL, and Core Plasma Fueling and Carbon Sources in DIII-D (open access)

Comprehensive Measurements and Modeling of SOL, and Core Plasma Fueling and Carbon Sources in DIII-D

Plasma boundary modeling of low density, low confinement plasmas in DIII-D has been benchmarked against a comprehensive set of measurements and indicates that recycling of deuterium ions at the divertor targets, and chemical sputtering at the divertor target plates and walls, can explain the poloidal core fueling profile and core carbon density. Key measurements included the 2-D intensity distribution of deuterium neutral and low-charge state carbon emission in the divertor and around the midplane of the high-field scrape-off layer (SOL). Chemical sputtering plays an important role in producing carbon at the divertor targets and walls, and was found to be a prerequisite to reproduce the measured emission distribution.
Date: June 24, 2005
Creator: Groth, M.; Porter, G.; Bray, B.; Brooks, N.; Fenstermacher, M.; Groebner, R. et al.
System: The UNT Digital Library
A conservative three-dimensional Eulerian method for coupled fluid-solid shock capturing (open access)

A conservative three-dimensional Eulerian method for coupled fluid-solid shock capturing

None
Date: June 24, 2002
Creator: Miller, G. H. & Colella, P.
System: The UNT Digital Library
Controlling the length scale and distribution of the ductile phase in metallic glass composites through friction stir processing (open access)

Controlling the length scale and distribution of the ductile phase in metallic glass composites through friction stir processing

This article demonstrates the refinement and uniform distribution of the crystalline dendritic phase by friction stir processing of titanium based in situ ductile-phase reinforced metallic glass composite.
Date: June 24, 2014
Creator: Singh Arora, Harpreet; Mridha, Sanghita; Singh Grewal, Harpeet; Singh, Harpreet; Hofmann, Douglas C. & Mukherjee, Sundeep
System: The UNT Digital Library
Corrosion Behavior of Alloy 22 in Oxalic Acid and Sodium Chloride Solutions (open access)

Corrosion Behavior of Alloy 22 in Oxalic Acid and Sodium Chloride Solutions

Nickel based Alloy 22 (NO6022) is extensively used in aggressive industrial applications, especially due to its resistance to localized corrosion and stress corrosion cracking in high chloride environments. The purpose of this work was to characterize the anodic behavior of Alloy 22 in oxalic acid solution and to compare its behavior to sodium chloride (NaCl) solutions. Standard electrochemical tests such as polarization resistance and cyclic polarization were used. Results show that the corrosion rate of Alloy 22 in oxalic acid solutions increased rapidly as the temperature and the acid concentration increased. Extrapolation studies show that even at a concentration of 10{sup -4}M oxalic acid, the corrosion rate of Alloy 22 would be higher in oxalic acid than in 1 M NaCl solution. Alloy 22 was not susceptible to localized corrosion in oxalic acid solutions. Cyclic polarization tests in 1 M NaCl showed that Alloy 22 was susceptible to crevice corrosion at 90 C but was not susceptible at 60 C.
Date: June 24, 2003
Creator: Day, S. D.; Whalen, M. T.; King, K. J.; Hust, G. A.; Wong, L. L.; Estill, J. C. et al.
System: The UNT Digital Library
Cosmological Constraints from Galaxy Clustering and the Mass-to-Number Ratio of Galaxy Clusters: Marginalizing Over the Physics of Galaxy Formation (open access)

Cosmological Constraints from Galaxy Clustering and the Mass-to-Number Ratio of Galaxy Clusters: Marginalizing Over the Physics of Galaxy Formation

None
Date: June 24, 2013
Creator: Reddick, Rachel; Tinker, Jeremy; Wechsler, Risa & Lu, Yu
System: The UNT Digital Library
Crystallization pathway in the bulk metallic glass Zr{sub 41.2}Ti{sub 13.8}Cu{sub 12.5}Ni{sub 10}Be{sub 22.5}. (open access)

Crystallization pathway in the bulk metallic glass Zr{sub 41.2}Ti{sub 13.8}Cu{sub 12.5}Ni{sub 10}Be{sub 22.5}.

A new family of multicomponent metallic alloys exhibits an excellent glass forming ability at moderate cooling rates of about 10K/s and a wide supercooled liquid region. These glasses are eutectic or nearly eutectic, thus far away from the compositions of competing crystalline phases. The nucleation of crystals from the homogeneous amorphous phase requires large thermally activated composition fluctuations for which the time scale is relatively long, even in the supercooled liquid. In the Zr{sub 41.2}Ti{sub 13.8}Cu{sub 12.5}Ni{sub 10}Be{sub 22.5} alloy therefore a different pathway to crystallization is observed. The initially homogeneous alloy separates into two amorphous phases. In the decomposed regions, crystallization probability increases and finally polymorphic crystallization occurs. The evolution of decomposition and succeeding primary crystallization in the bulk amorphous Zr{sub 41.2}Ti{sub 13.8}Cu{sub 12.5}Ni{sub 10}Be{sub 22.5}, alloy have been studied by small angle neutron. Samples annealed isothermally in the supercooled liquid and in the solid state exhibit interference peaks indicating quasiperiodic inhomogeneities in the scattering length density. The related wavelengths increase with temperature according to the linear Cahn-Hilliard theory for spinodal decomposition. Also the time evolution of the interference peaks in the early stages is consistent with this theory. At later stages, X-ray diffraction and transmission electron microscopy investigations …
Date: June 24, 1997
Creator: Geyer, U.; Johnson, W. L.; Schneider, S. & Thiyagarajan, P.
System: The UNT Digital Library
CURRENT STATUS OF VHE ASTRONOMY (open access)

CURRENT STATUS OF VHE ASTRONOMY

None
Date: June 24, 1999
Creator: SINNIS, G.
System: The UNT Digital Library
Data Structures and Algorithms for Graph Based Remote Sensed Image Content Storage and Retrieval (open access)

Data Structures and Algorithms for Graph Based Remote Sensed Image Content Storage and Retrieval

The Image Content Engine (ICE) project at Lawrence Livermore National Laboratory (LLNL) extracts, stores and allows queries of image content on multiple levels. ICE is designed for multiple application domains. The domain explored in this work is aerial and satellite surveillance imagery. The highest level of semantic information used in ICE is graph based. After objects are detected and classified, they are grouped based in their interrelations. The graph representing a locally related set of objects is called a 'graphlet'. Graphlets are interconnected into a larger graph which covers an entire set of images. Queries based on graph properties are notoriously difficult due the inherent complexity of the graph isomorphism and sub-graph isomorphism problems. ICE exploits limitations in graph and query structure and uses a set of auxiliary data structures to quickly process a useful set of graph based queries. These queries could not be processed using semantically lower level (tile and object based) queries.
Date: June 24, 2004
Creator: Grant, C W
System: The UNT Digital Library
Design and Testing of a Fast, 50 kV Solid-State Kicker Pulser (open access)

Design and Testing of a Fast, 50 kV Solid-State Kicker Pulser

The ability to extract particle beam bunches from a ring accelerator in arbitrary order can greatly extend an accelerator's capabilities and applications. A prototype solid-state kicker pulser capable of generating asynchronous bursts of 50 kV pulses has been designed and tested into a 50{Omega} load. The pulser features fast rise and fall times and is capable of generating an arbitrary pattern of pulses with a maximum burst frequency exceeding 5 MHz If required, the pulse-width of each pulse in the burst is independently adjustable. This kicker modulator uses multiple solid-state modules stacked in an inductive-adder configuration where the energy is switched into each section of the adder by a parallel array of MOSFETs. Test data, capabilities, and limitations of the prototype pulser are described.
Date: June 24, 2002
Creator: Cook, E. G.; Hickman, B. C.; Lee, B. S.; Hawkins, S. A.; Gower, E. J.; Allen, F. V. et al.
System: The UNT Digital Library