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Reconfigurable Surface Plasmon Polariton Wave Adapter Designed by Transformation Optics (open access)

Reconfigurable Surface Plasmon Polariton Wave Adapter Designed by Transformation Optics

This article proposes a reconfigurable surface plasmon polariton (SPP) wave adapter designed by transformation optics, which can control the propagation of SPP waves on un-even surfaces.
Date: June 18, 2012
Creator: Arigong, Bayaner; Shao, Jin; Ren, Han; Zheng, Geng; Lutkenhaus, Jeffrey; Kim, HyoungSoo et al.
System: The UNT Digital Library
Plasma blobs and filaments -- fusion scientists discover secrets of turbulent edge transport (open access)

Plasma blobs and filaments -- fusion scientists discover secrets of turbulent edge transport

None
Date: October 18, 2012
Creator: Cohen, B I; Myra, J; Garcia, O E; Smith, D & Parker, S E
System: The UNT Digital Library
Temperature-induced martensite in magnetic shape memory Fe{sub 2}MnGa observed by photoemission electron microscopy (open access)

Temperature-induced martensite in magnetic shape memory Fe{sub 2}MnGa observed by photoemission electron microscopy

The magnetic domain structure in single crystals of a Heusler shape memory compound near the composition Fe{sub 2}MnGa was observed during phase transition by photoelectron emission microscopy at Beamline 11.0.1.1 of the Advanced Light Source. The behavior is comparable with recent observations of an adaptive martensite phase in prototype Ni{sub 2}MnGa, although the pinning in the recent work is an epitaxial interface and in this work the e#11;ective pinning plane is a boundary between martensitic variants that transform in a self-accommodating way from the single crystal austenite phase present at high temperatures. Temperature dependent observations of the twinning structure give information as to the coupling behavior between the magnetism and the structural evolution.
Date: January 18, 2012
Creator: Jenkins, Catherine; Scholl, Andreas; Kainuma, R.; Elmers, Hans-Joachim & Omori, Toshihiro
System: The UNT Digital Library
Interactions of Ionic Liquids with Uranium and its Bioreduction (open access)

Interactions of Ionic Liquids with Uranium and its Bioreduction

We investigated the influence of ionic liquids (ILs) 1-butyl-3-methylimidazolium hexafluorophosphate [BMIM]{sup +}[PF{sub 6}]{sup -}, N-ethylpyridinium trifluoroacetate [EtPy]{sup +}[CF{sub 3}COO]{sup -} and N-ethylpyridinium tetrafluoroborate [Et-Py]{sup +}[BF{sub 4}]{sup -} on uranium reduction by Clostridium sp. under anaerobic conditions. Potentiometric titration, UV-vis spectrophotometry, LC-MS and EXAFS analyses showed monodentate complexation between uranyl and BF{sub 4}{sup -} PF{sub 6}{sup -}; and bidentate complexation with CF{sub 3}COO{sup -}. Ionic liquids affected the growth of Clostridium sp. as evidenced by decrease in optical density, changes in pH, gas production, and the extent of U(VI) reduction and precipitation of U(IV) from solution. Reduction of U(VI) to U(IV) was observed in the presence of [EtPy][BF{sub 4}] and [BMIM][PF{sub 6}] but not with [EtPy][CF{sub 3}COO].
Date: September 18, 2012
Creator: Zhang, C. & Francis, A.
System: The UNT Digital Library
Using fully coupled hydro-geomechanical numerical test bed to study reservoir stimulation with low hydraulic pressure (open access)

Using fully coupled hydro-geomechanical numerical test bed to study reservoir stimulation with low hydraulic pressure

None
Date: January 18, 2012
Creator: Fu, P.; Johnson, S. M. & Carrigan, C. R.
System: The UNT Digital Library
Performance measurements of the DIXI (dilation x-ray imager) photocathode using a laser produced x-ray source (open access)

Performance measurements of the DIXI (dilation x-ray imager) photocathode using a laser produced x-ray source

None
Date: July 18, 2012
Creator: Nagel, S R; Ayers, M J; Felker, B; Smith, R F; Bell, P M; Bradley, D K et al.
System: The UNT Digital Library
Hearing Nano-Structures: A Case Study in Timbral Sonification (open access)

Hearing Nano-Structures: A Case Study in Timbral Sonification

We explore the sonification of x-ray scattering data, which are two-dimensional arrays of intensity whose meaning is obscure and non-intuitive. Direct mapping of the experimental data into sound is found to produce timbral sonifications that, while sacrificing conventional aesthetic appeal, provide a rich auditory landscape for exploration. We discuss the optimization of sonification variables, and speculate on potential real-world applications. We have presented a case study of sonifying x-ray scattering data. Direct mapping of the two-dimensional intensity values of a scattering dataset into the two-dimensional matrix of a sonogram is a natural and information-preserving operation that creates rich sounds. Our work supports the notion that many problems in understanding rather abstract scientific datasets can be ameliorated by adding the auditory modality of sonification. We further emphasize that sonification need not be limited to time-series data: any data matrix is amenable. Timbral sonification is less obviously aesthetic, than tonal sonification, which generate melody, harmony, or rhythm. However these musical sonifications necessarily sacrifice information content for beauty. Timbral sonification is useful because the entire dataset is represented. Non-musicians can understand the data through the overall color of the sound; audio experts can extract more detailed insight by studying all the features of …
Date: June 18, 2012
Creator: Schedel, M. & Yager, K.
System: The UNT Digital Library
Remote Handled Transuranic Sludge Retrieval Transfer And Storage System At Hanford (open access)

Remote Handled Transuranic Sludge Retrieval Transfer And Storage System At Hanford

This paper describes the systems developed for processing and interim storage of the sludge managed as remote-handled transuranic (RH-TRU). An experienced, integrated CH2M HILL/AFS team was formed to design and build systems to retrieve, interim store, and treat for disposal the K West Basin sludge, namely the Sludge Treatment Project (STP). A system has been designed and is being constructed for retrieval and interim storage, namely the Engineered Container Retrieval, Transfer and Storage System (ECRTS).
Date: October 18, 2012
Creator: Raymond, Rick E.; Frederickson, James R.; Criddle, James; Hamilton, Dennis & Johnson, Mike W.
System: The UNT Digital Library
Status of Monte-Carlo Event Generators (open access)

Status of Monte-Carlo Event Generators

None
Date: October 18, 2012
Creator: Hoeche, Stefan
System: The UNT Digital Library
The Role of Groups of Scientific Experts in Facilitating Better International Relations, Particularly in Arms Control. (open access)
Performance of a 512 x 512 Gated CMOS Imager with a 250 ps Exposure Time (open access)

Performance of a 512 x 512 Gated CMOS Imager with a 250 ps Exposure Time

None
Date: July 18, 2012
Creator: Teruya, A. T.; Vernon, S. P.; Moody, J. D.; Hsing, W. W.; Brown, C. G.; Griffin, M. et al.
System: The UNT Digital Library
An Experiment to Locate the Site of TeV Flaring in M87 (open access)

An Experiment to Locate the Site of TeV Flaring in M87

We describe a Chandra X-ray target-of-opportunity project designed to isolate the site of TeV flaring in the radio galaxy M87. To date, we have triggered the Chandra observations only once (2010 April) and by the time of the first of our nine observations, the TeV flare had ended. However, we found that the X-ray intensity of the unresolved nucleus was at an elevated level for our first observation. Of the more than 60 Chandra observations we have made of the M87 jet covering nine years, the nucleus was measured at a comparably high level only three times. Two of these occasions can be associated with TeV flaring, and at the time of the third event, there were no TeV monitoring activities. From the rapidity of the intensity drop of the nucleus, we infer that the size of the emitting region is of order a few light days x the unknown beaming factor; comparable to the same sort of estimate for the TeV emitting region. We also find evidence of spectral evolution in the X-ray band which seems consistent with radiative losses affecting the non-thermal population of the emitting electrons within the unresolved nucleus.
Date: May 18, 2012
Creator: Harris, D. E.; Massaro, F.; Cheung, C. C.; Horns, D.; Raue, M.; Stawarz, L. et al.
System: The UNT Digital Library
Status of the Super-B factory Design (open access)

Status of the Super-B factory Design

The SuperB international team continues to optimize the design of an electron-positron collider, which will allow the enhanced study of the origins of flavor physics. The project combines the best features of a linear collider (high single-collision luminosity) and a storage-ring collider (high repetition rate), bringing together all accelerator physics aspects to make a very high luminosity of 10{sup 36} cm{sup -2} sec{sup -1}. This asymmetric-energy collider with a polarized electron beam will produce hundreds of millions of B-mesons at the Y(4S) resonance. The present design is based on extremely low emittance beams colliding at a large Piwinski angle to allow very low {beta}{sub y} without the need for ultra short bunches. Use of crab-waist sextupoles will enhance the luminosity, suppressing dangerous resonances and allowing for a higher beam-beam parameter. The project has flexible beam parameters, improved dynamic aperture, and spin-rotators in the Low Energy Ring for longitudinal polarization of the electron beam at the Interaction Point. Optimized for best colliding-beam performance, the facility may also provide high-brightness photon beams for synchrotron radiation applications.
Date: May 18, 2012
Creator: Wittmer, W.; U., /Michigan State; Bertsche, K.; Chao, A.; Novokhatski, A.; Nosochkov, Y. et al.
System: The UNT Digital Library
NEW MATERIALS DEVELOPED TO MEET REGULATORY AND TECHNICAL REQUIREMENTS ASSOCIATED WITH IN-SITU DECOMMISSIONING OF NUCLEAR REACTORS AND ASSOCIATED FACILITIES (open access)

NEW MATERIALS DEVELOPED TO MEET REGULATORY AND TECHNICAL REQUIREMENTS ASSOCIATED WITH IN-SITU DECOMMISSIONING OF NUCLEAR REACTORS AND ASSOCIATED FACILITIES

For the 2010 ANS Embedded Topical Meeting on Decommissioning, Decontamination and Reutilization and Technology, Savannah River National Laboratory's Mike Serrato reported initial information on the newly developed specialty grout materials necessary to satisfy all requirements associated with in-situ decommissioning of P-Reactor and R-Reactor at the U.S. Department of Energy's Savannah River Site. Since that report, both projects have been successfully completed and extensive test data on both fresh properties and cured properties has been gathered and analyzed for a total of almost 191,150 m{sup 3} (250,000 yd{sup 3}) of new materials placed. The focus of this paper is to describe the (1) special grout mix for filling the P-Reactor vessel (RV) and (2) the new flowable structural fill materials used to fill the below grade portions of the facilities. With a wealth of data now in hand, this paper also captures the test results and reports on the performance of these new materials. Both reactors were constructed and entered service in the early 1950s, producing weapons grade materials for the nation's defense nuclear program. R-Reactor was shut down in 1964 and the P-Reactor in 1991. In-situ decommissioning (ISD) was selected for both facilities and performed as Comprehensive Environmental Response, Compensations …
Date: January 18, 2012
Creator: Blankenship, J.; Langton, C.; Musall, J. & Griffin, W.
System: The UNT Digital Library
Charge Pump Detector: Optimization with Process and Device Simulation (open access)

Charge Pump Detector: Optimization with Process and Device Simulation

None
Date: December 18, 2012
Creator: Segal, Julie D. & Kenney, Christopher J.
System: The UNT Digital Library
Synchrotron Light Options at Super-B (open access)

Synchrotron Light Options at Super-B

None
Date: May 18, 2012
Creator: Wittmer, Walter; Nosochkov, Yuri; Novokhatski, Alexander; Seeman, John; Sullivan, Michael; Biagini, Maria Enrica et al.
System: The UNT Digital Library
A Low-Frequency Model for E-Field and B-Field Coupling into a Folded Antenna with Two Gaps (open access)

A Low-Frequency Model for E-Field and B-Field Coupling into a Folded Antenna with Two Gaps

None
Date: January 18, 2012
Creator: Perkins, M. P.; Ong, M. M. & Robbins, C. L.
System: The UNT Digital Library
Feature Extraction of PDV Challenge Data Set A with Digital Down Shift (DDS) (open access)

Feature Extraction of PDV Challenge Data Set A with Digital Down Shift (DDS)

This slide-show is about data analysis in photonic Doppler velocimetry. The digital down shift subtracts a specified velocity (frequency) from all components in the Fourier frequency domain and generates both the down shifted in-phase and out-of-phase waveforms so that phase and displacement can be extracted through a continuous unfold of the arctangent.
Date: October 18, 2012
Creator: Tunnell, T. W.
System: The UNT Digital Library
Numerical Reproducibility for Implicit Monte Carlo Simulations (open access)

Numerical Reproducibility for Implicit Monte Carlo Simulations

None
Date: October 18, 2012
Creator: Cleveland, M.; Brunner, T. & Gentile, N.
System: The UNT Digital Library
Response of NSTX Liquid Lithium divertor to High Heat Loads (open access)

Response of NSTX Liquid Lithium divertor to High Heat Loads

Samples of the NSTX Liquid Lithium Divertor (LLD) with and without an evaporative Li coating were directly exposed to a neutral beam ex-situ at a power of ~1.5 MW/m2 for 1-3 seconds. Measurements of front face and bulk sample temperature were obtained. Predictions of temperature evolution were derived from a 1D heat flux model. No macroscopic damage occurred when the "bare" sample was exposed to the beam but microscopic changes to the surface were observed. The Li-coated sample developed a lithium hydroxide (LiOH) coating, which did not change even when the front face temperature exceeded the pure Li melting point. These results are consistent with the lack of damage to the LLD surface and imply that heating alone may not expose pure liquid Li if the melting point of surface impurities is not exceeded. This suggests that flow and heat are needed for future PFCs requiring a liquid Li surface. __________________________________________________
Date: July 18, 2012
Creator: Abrams, Tyler; Kallman, J; Kaitaa, R; Foley, E L; Grayd, T K; Kugel, H et al.
System: The UNT Digital Library
RELAP5 Application to Accident Analysis of the NIST Research Reactor (open access)

RELAP5 Application to Accident Analysis of the NIST Research Reactor

Detailed safety analyses have been performed for the 20 MW D{sub 2}O moderated research reactor (NBSR) at the National Institute of Standards and Technology (NIST). The time-dependent analysis of the primary system is determined with a RELAP5 transient analysis model that includes the reactor vessel, the pump, heat exchanger, fuel element geometry, and flow channels for both the six inner and twenty-four outer fuel elements. A post-processing of the simulation results has been conducted to evaluate minimum critical heat flux ratio (CHFR) using the Sudo-Kaminaga correlation. Evaluations are performed for the following accidents: (1) the control rod withdrawal startup accident and (2) the maximum reactivity insertion accident. In both cases the RELAP5 results indicate that there is adequate margin to CHF and no damage to the fuel will occur because of sufficient coolant flow through the fuel channels and the negative scram reactivity insertion.
Date: March 18, 2012
Creator: Baek, J.; Cuadra Gascon, A.; Cheng, L. Y. & Diamond, D.
System: The UNT Digital Library
Impact parameter dependence of the nuclear modification of J/psi production in d+Au collisions at sNN = 200 GeV (open access)

Impact parameter dependence of the nuclear modification of J/psi production in d+Au collisions at sNN = 200 GeV

None
Date: July 18, 2012
Creator: McGlinchey, D C; Frawley, A D & Vogt, R
System: The UNT Digital Library
Editorial: Applications of Light Detection and Ranging (LiDAR) in Geosciences (open access)

Editorial: Applications of Light Detection and Ranging (LiDAR) in Geosciences

This article contains an editorial on applications of Light Detection and Ranging (LiDAR) in Geosciences.
Date: August 18, 2012
Creator: Dong, Pinliang
System: The UNT Digital Library