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High-resolution NMR spectroscopy of biological tissues using projected Magic Angle Spinning (open access)

High-resolution NMR spectroscopy of biological tissues using projected Magic Angle Spinning

High-resolution NMR spectra of materials subject toanisotropic broadening are usually obtained by rotating the sample aboutthe magic angle, which is 54.7 degrees to the static magnetic field. Inprojected Magic Angle Spinning (p-MAS), the sample is spun about twoangles, neither of which is the magic angle. This provides a method ofobtaining isotropic spectra while spinning at shallow angles. The p-MASexperiment may be used in situations where spinning the sample at themagic angle is not possible due to geometric or other constraints,allowing the choice of spinning angle to be determined by factors such asthe shape of the sample, rather than by the spin physics. The applicationof this technique to bovine tissue samples is demonstrated as a proof ofprinciple for future biological or medical applications.
Date: January 27, 2005
Creator: Martin, Rachel W.; Jachmann, Rebecca C.; Sakellariou, Dimitris; Nielsen, Ulla Gro & Pines, Alexander
System: The UNT Digital Library
High Temperature Strain Gages for SOFC Application (open access)

High Temperature Strain Gages for SOFC Application

This presentation discusses the investigation/extension of high temperature strain gage applications sensors to SOFC applications.
Date: January 27, 2005
Creator: Pineault, R. L.; Johnson, C.; Gemmen, R. S.; Gregory, O. & You, T.
System: The UNT Digital Library
Material Interface Reconstruction in VisIt (open access)

Material Interface Reconstruction in VisIt

In this paper, we first survey a variety of approaches to material interface reconstruction and their applicability to visualization, and we investigate the details of the current reconstruction algorithm in the VisIt scientific analysis and visualization tool. We then provide a novel implementation of the original VisIt algorithm that makes use of a wide range of the finite element zoo during reconstruction. This approach results in dramatic improvements in quality and performance without sacrificing the strengths of the VisIt algorithm as it relates to visualization.
Date: January 27, 2005
Creator: Meredith, J S
System: The UNT Digital Library
The Modular Point Design for Heavy Ion Fusion (open access)

The Modular Point Design for Heavy Ion Fusion

We report on an ongoing study on modular Heavy Ion Fusion drivers. The modular driver is characterized by tens ({approx} 20) nearly identical induction linacs, each carrying a single high current beam. In this scheme, the Integrated Research Experiment (IRE) can be one of the full size induction linacs. Hence, this approach offers significant advantages in terms of driver development path. For beam transport, these modules use solenoids which are capable of carrying high line charge densities, even at low energies. A new injector concept allows compression of the beam to high line densities right at the source. The final drift compression is performed in a plasma, in which the large repulsive space charge effects are neutralized. Finally, the beam is transversely compressed onto the target, using either external solenoids or current-carrying channels (in the Assisted Pinch Mode of beam propagation). We will report on progress towards a self-consistent point design from injector to target. Considerations of driver architecture, chamber environment as well as the methodology for meeting target requirements of spot size, pulse shape and symmetry will also be described. Finally, some near-term experiments to address the key scientific issues will be discussed.
Date: January 27, 2005
Creator: Yu, S. S.; Barnard, J. J.; Briggs, R. J.; Callahan-Miller, D.; Celata, C. M.; Chao, L. et al.
System: The UNT Digital Library
Proton Fast Ignition (open access)

Proton Fast Ignition

None
Date: January 27, 2005
Creator: Key, M. H.; Freeman, R. R.; Hatchett, S. P.; MacKinnon, A. J.; Patel, P. K.; Snavely, R. A. et al.
System: The UNT Digital Library
QLC relation and neutrino mass hierarchy (open access)

QLC relation and neutrino mass hierarchy

Latest measurements have revealed that the deviation from a maximal solar mixing angle is approximately the Cabibbo angle, i.e., QLC relation. We argue that it is not plausible that this deviation from maximality, be it a coincidence or not, comes from the charged lepton mixing. Consequently we have calculated the required corrections to the exactly bimaximal neutrino mass matrix ansatz necessary to account for the solar mass difference and the solar mixing angle. We point out that the relative size of these two corrections depends strongly on the hierarchy case under consideration. We find that the inverted hierarchy case with opposite CP parities, which is known to guarantee the RGE stability of the solar mixing angle, offers the most plausible scenario for a high energy origin of a QLC-corrected bimaximal neutrino mass matrix. This possibility may allow us to explain the QLC relation in connection with the origin of the charged fermion mass matrices.
Date: January 27, 2005
Creator: Ferrandis, Javier & Pakvasa, Sandip
System: The UNT Digital Library
SECA Core Program - Recent Development of Modeling Activities at PNNL (open access)

SECA Core Program - Recent Development of Modeling Activities at PNNL

This presentation discusses recent modeling activities at the Pacific Northwest National Laboratory.
Date: January 27, 2005
Creator: Khaleel, M. A.; Recknagle, K. P.; Koeppel, B.; Vetrano, J.; Sun, X.; Korolev, V. et al.
System: The UNT Digital Library
Transport & Disposal of TPBARs at the Tritium Extraction Facility (open access)

Transport & Disposal of TPBARs at the Tritium Extraction Facility

As a part of the Department of Energy Tritium Readiness Program, the Tritium Extraction Facility (TEF) at the Savannah River Site (SRS) is preparing to receive the first shipment of irradiated Tritium Producing Burnable Absorber Rods (TPBARs) from the Tennessee Valley Authority's Watts Bar Nuclear Plant. Tritium will be extracted from the TPBARs at the TEF. The spent TPBARs will be transported and disposed on site using the TEF Waste Container, designed and fabricated by Packaging Technology, Inc. This paper describes the TPBAR waste form, the TEF Waste Container to be used to store the waste, the operational sequence associated with management of the TBPAR waste form and the disposal facility at the SRS.
Date: January 27, 2005
Creator: BENJAMIN, SNIDER
System: The UNT Digital Library
Cesium Ion Exchange Program at the Hanford River Protection Project Waste Treatment Plant (open access)

Cesium Ion Exchange Program at the Hanford River Protection Project Waste Treatment Plant

The Hanford Waste Treatment and Immobilization Plant (WTP) will use cesium ion exchange to remove Cs-137 from Low Activity Waste (LAW) down to a maximum activity of 0.3 Ci/m3 in the Immobilized LAW (ILAW) product. The WTP Project baseline for cesium ion exchange is the elutable SuperLig(R) 644 (SL-644) resin (registered trademark of IBC Advanced Technologies, Inc., American Fork, UT) or a U. S. Department of Energy (DOE) approved equivalent. SL-644 is solely available through IBC Advanced Technologies. The WTP Project is conducting a three-stage process for selecting and qualifying an alternative ion exchange resin. Resorcinol formaldehyde (RF) is being pursued as a potential alternative to SL-644, to provide a backup resin supply. Resin cost relative to SL-644 is a primary driver. Phase I of the testing plan examined the viability of RF resin and recommended that a spherical form of RF resin be examined further. Phases II and III, now underway, include batch testing to determine the isotherm of this resin, kinetics to address the impacts of bead diameter and high sodium feed levels on processing Hanford waste with the resin, and multicycle column testing to determine how temperature and chemical cycling affects waste processing. Phases II and III …
Date: February 27, 2005
Creator: CHARLES, NASH
System: The UNT Digital Library
CP VIOLATION HIGHLIGHTS: CIRCA 2005 (open access)

CP VIOLATION HIGHLIGHTS: CIRCA 2005

Recent highlights in CP violation phenomena, are reviewed. B-factory results imply that, CP-violation phase in the CKM matrix is the dominant contributor to the observed CP violation in K and B-physics. Deviations from the predictions of the CKM-paradigm due to beyond the Standard Model CP-odd phase are likely to be a small perturbation. Therefore, large data sample of clean B's will be needed. Precise determination of the unitarity triangle, along with time dependent CP in penguin dominated hadronic and radiative modes are discussed. Null tests in B, K and top-physics and separate determination of the K-unitarity triangle are also emphasized.
Date: February 27, 2005
Creator: A., SONI
System: The UNT Digital Library
Engineering Monosodium Titanate for Adsorption Column Processes (open access)

Engineering Monosodium Titanate for Adsorption Column Processes

Monosodium titanate is an inorganic adsorbent powder that effectively removes strontium, plutonium, neptunium, and other trace elements from alkaline high-level waste supernate. This work tested one commercial titanate and four general methods to engineer MST into particles large enough to use in adsorption columns. The most successful of the engineered products selected from batch contact and chemical stability testing succeeded in treating 2900 bed volumes of simulated salt waste containing dissolved plutonium and strontium. There was no detectable strontium breakthrough and only 6 percent plutonium breakthrough--well within the processing goal--at the end of the demonstration which operated at 5.3 BV/hour. Additional column tests at nominally 15 BV/hr demonstrated similar removal performance. Batch testing of adsorbents used both actual Savannah River Site tank supernate as well as simulated salt solutions spiked with strontium, neptunium, and plutonium. In tank waste tests, internal gelation beads produced by the Oak Ridge National Laboratory demonstrated a batch distribution coefficient of 35,000 +/- 4,000 mL/g for plutonium at a phase ratio of 1970 mL/g. In the same batch the sorbent demonstrated a batch distribution coefficient of 99,000 +/- 7,500 mL/g for strontium. These results indicate that this material should be able to process thousands of bed …
Date: February 27, 2005
Creator: CHARLES, NASH
System: The UNT Digital Library
Charge Exchange Spectra of Hydrogenic and He-like Iron (open access)

Charge Exchange Spectra of Hydrogenic and He-like Iron

We present H-like Fe XXVI and He-like Fe XXV charge-exchange spectra resulting from collisions of highly charged iron with N{sub 2} gas at an energy of {approx}10 eV amu{sup -1} in an electron beam ion trap. Although high-n emission lines are not resolved in our measurements, we observe that the most likely level for Fe{sup 25+} {yields} Fe{sup 24+} electron capture is n{sub max} {approx} 9, in line with expectations, while the most likely value for Fe{sup 26+} {yields} Fe{sup 25+} charge exchange is significantly higher. In the Fe XXV spectrum, the K{alpha} emission feature dominates, whether produced via charge exchange or collisional excitation. The K{alpha} energy centroid is lower in the former case than the latter (6666 versus 6685 eV, respectively), as expected because of the strong enhancement of emission from the forbidden and intercombination lines, relative to the resonance line, in charge-exchange spectra. In contrast, the Fe XXVI high-n Lyman lines have a summed intensity greater than that of Ly{alpha}, and are substantially stronger than predicted from theoretical calculations of charge exchange with atomic H. A discussion is presented of the relevance of our results to studies of diffuse Fe emission in the Galactic Center and Galactic Ridge, …
Date: April 27, 2005
Creator: Wargelin, B J; Beiersdorfer, P; Neill, P A; Olson, R E & Scofield, J H
System: The UNT Digital Library
A Combined Experimental and Computational Approach for the Design of Mold Topography that Leads to Desired Ingot Surface and Microstructure in Aluminum Casting. (open access)

A Combined Experimental and Computational Approach for the Design of Mold Topography that Leads to Desired Ingot Surface and Microstructure in Aluminum Casting.

Solidification of dendritic alloys is modeled using stabilized finite element techniques to study convection and macrosegregation driven by buoyancy and shrinkage. The adopted governing macroscopic conservation equations of momentum, energy and species transport are derived from their microscopic counterparts using the volume-averaging method. A single domain model is considered with a fixed numerical grid and without boundary conditions applied explicitly on the freezing front. The mushy zone is modeled here as a porous medium with either an isotropic or an anisotropic permeability. The stabilized finite-element scheme, previously developed by authors for modeling flows with phase change, is extended here to include effects of shrinkage, density changes and anisotropic permeability during solidification. The fluid flow scheme developed includes streamline-upwind/Petrov-Galerkin (SUPG), pressure stabilizing/Petrov-Galerkin, Darcy stabilizing/Petrov-Galerkin and other stabilizing terms arising from changes in density in the mushy zone. For the energy and species equations a classical SUPG-based finite element method is employed with minor modifications. The developed algorithms are first tested for a reference problem involving solidification of lead-tin alloy where the mushy zone is characterized by an isotropic permeability. Convergence studies are performed to validate the simulation results. Solidification of the same alloy in the absence of shrinkage is studied to …
Date: April 27, 2005
Creator: Dr. Zabaras, N. & Samanta, D.
System: The UNT Digital Library
Development of Chaos in the Color Glass Condensate. (open access)

Development of Chaos in the Color Glass Condensate.

Noting that the number of gluons in the hadron wave function is discrete, and their formation in the chain of small x evolution occurs over discrete rapidity intervals of {Delta}y {approx} 1/{alpha}{sub s}, we formulate the discrete version of the Balitsky-Kovchegov evolution equation and show that its solution behaves chaotically in the phenomenologically interesting kinematic region.
Date: April 27, 2005
Creator: Tuchin, K.
System: The UNT Digital Library
DIFFRACTION DISSOCIATION - 50 YEARS LATER. (open access)

DIFFRACTION DISSOCIATION - 50 YEARS LATER.

The field of Diffraction Dissociation, which is the subject of this workshop, began 50 years ago with the analysis of deuteron stripping in low energy collisions with nuclei. We return to the subject in a modern context- deuteron dissociation in {radical}s{sub NN} = 200 GeV d-Au collisions recorded during the 2003 RHIC run in the PHENIX experiment. At RHIC energy, d {yields} n+p proceeds predominantly (90%) through Electromagnetic Dissociation and the remaining fraction via the hadronic shadowing described by Glauber. Since the dissociation cross section has a small theoretical error we adopt this process to normalize other cross sections measured in RHIC.
Date: April 27, 2005
Creator: White, Sebastian N.
System: The UNT Digital Library
Model-based Processing of Microcantilever Sensor Arrays (open access)

Model-based Processing of Microcantilever Sensor Arrays

We have developed a model-based processor (MBP) for a microcantilever-array sensor to detect target species in solution. We perform a proof-of-concept experiment, fit model parameters to the measured data and use them to develop a Gauss-Markov simulation. We then investigate two cases of interest, averaged deflection data and multi-channel data. For this evaluation we extract model parameters via a model-based estimation, perform a Gauss-Markov simulation, design the optimal MBP and apply it to measured experimental data. The performance of the MBP in the multi-channel case is evaluated by comparison to a ''smoother'' (averager) typically used for microcantilever signal analysis. It is shown that the MBP not only provides a significant gain ({approx} 80dB) in signal-to-noise ratio (SNR), but also consistently outperforms the smoother by 40-60 dB. Finally, we apply the processor to the smoothed experimental data and demonstrate its capability for chemical detection. The MBP performs quite well, apart from a correctable systematic bias error.
Date: April 27, 2005
Creator: Tringe, J W; Clague, D S; Candy, J V; Sinensky, A K; Lee, C L; Rudd, R E et al.
System: The UNT Digital Library
NEXT-TO-LEADING ORDER ZCD CORRECTOINS TO ATT FOR SINGLE-INCLUSIVE HADRON PRODUCTION. (open access)

NEXT-TO-LEADING ORDER ZCD CORRECTOINS TO ATT FOR SINGLE-INCLUSIVE HADRON PRODUCTION.

We report on a calculation of the next-to-leading order QCD corrections to the partonic cross sections contributing to single-inclusive high-p{sub T} hadron production in collisions of transversely polarized hadrons. We give some predictions for the double spin asymmetry A{sub TT}{sup {pi}} for the proposed experiments at RHIC and at the GSI.
Date: April 27, 2005
Creator: MUKHERJEE, A.; STRATMANN, M. & VOGELSANG, W.
System: The UNT Digital Library
QCD FACTORIZATION FOR SEMI-INCLUSIVE DEEP INELASTIC SCATTERING. (open access)

QCD FACTORIZATION FOR SEMI-INCLUSIVE DEEP INELASTIC SCATTERING.

In this talk, we will present a QCD factorization theorem for the semi-inclusive deep-inelastic scattering with hadrons in the current fragmentation region detected at low transverse momentum.
Date: April 27, 2005
Creator: YUAN, F.
System: The UNT Digital Library
A Radiocarbon Chronology of Hunter-Gatherer Occupation from Bodega Bay, California, USA (open access)

A Radiocarbon Chronology of Hunter-Gatherer Occupation from Bodega Bay, California, USA

The evolution of hunter-gatherer maritime adaptations in western North America has been a prominent topic of discussion among archaeologists in recent years (e.g. Arnold 1992; Erlandson and Colten 1991; Erlandson and Glassow 1997; Lightfoot 1993). Although vast coastal regions of the northeastern Pacific (for example, southern California) have been investigated in detail, our understanding of hunter-gatherer developments along the coast of northern California is limited. Previous research indicates that humans have exploited marine mammals, fish and shellfish along the northern California shoreline since the early Holocene (Schwaderer 1992). By the end of the late Holocene, some groups remained year-round on the coast subsisting primarily on marine resources (e.g. Gould 1975; Hildebrandt and Levulett 2002). However, a paucity of well-dated cultural deposits has hindered our understanding of these developments, particularly during the early and middle Holocene. The lack of a long and reliable chronological sequence has restricted our interpretations of behavioral change, including the adaptive strategies (such as foraging, mobility and settlement) used by human foragers to colonize and inhabit the coastal areas of this region. These shortcomings have also hindered comparative interpretations with other coastal and inland regions in western North America. Here we present a Holocene radiocarbon chronology of …
Date: April 27, 2005
Creator: Kennedy, M. A.; Russell, A. D. & Guilderson, T. P.
System: The UNT Digital Library
Achieving Large Dynamic Aperture in the ILC Damping Rings (open access)

Achieving Large Dynamic Aperture in the ILC Damping Rings

The Damping Rings for the International Linear Collider have challenging requirements for the acceptance, because of the high average injected beam power and the large beam produced from the positron source. At the same time, the luminosity goals mean that the natural emittance must be very small, and this makes it particularly difficult to achieve a good dynamic aperture. We describe design approaches and lattice designs that meet the emittance specification and have very promising dynamic aperture.
Date: May 27, 2005
Creator: Wolski, A.; Cai, Y & /LBL, Berkeley /SLAC
System: The UNT Digital Library
Analysis of Positron Collection in the Linear Collider (open access)

Analysis of Positron Collection in the Linear Collider

In the Linear Collider, the positron capture system includes a positron production target, an adiabatic matching device (AMD), and a linac to accelerate positrons up to the injection energy of the positron damping ring. Efficiency of the positron collector is defined by the number of positrons accepted into the damping ring. Analysis of the positron collection system is performed using a conventional scheme, where positrons are produced by a high-energy electron beam hitting the high-Z target. The collection system has been optimized to insure high positron capture into the 6-dimensional acceptance of the damping ring. Various parameters affecting the positron capture are analyzed.
Date: May 27, 2005
Creator: Batygin, Yuri K.af SLAC
System: The UNT Digital Library
Dark Currents and Their Effect on the Primary Beam in an X-band Linac (open access)

Dark Currents and Their Effect on the Primary Beam in an X-band Linac

We numerically study properties of primary dark currents in an X-band accelerating structure. For the H60VG3 structure considered for the Next Linear Collider (NLC) we first perform a fairly complete (with some approximations) calculation of dark current trajectories. These results are used to study properties of the dark current leaving the structure. For example, at accelerating gradient of 65 MV/m, considering two very different assumptions about dark current emission around the irises, we find that the fraction of emitted current leaving the structure to be a consistent {approx} 1%. Considering that {approx} 1 mA outgoing dark current is seen in measurement, this implies that {approx} 100 mA (or 10 pC per period) is emitted within the structure itself. Using the formalism of the Lienard-Wiechert potentials, we then perform a systematic calculation of the transverse kick of dark currents on a primary linac bunch. The result is {approx} 1 V kick per mA (or per 0.1 pC per period) dark current emitted from an iris. For an entire structure we estimate the total kick on a primary bunch to be {approx} 15 V. For the NLC linac this translates to a ratio of (final) vertical beam offset to beam size of …
Date: May 27, 2005
Creator: Bane, K .L. F.; Dolgashev, V. A.; Raubenheimer, Tor; Stupakov, G. V. & Wu, J. H.
System: The UNT Digital Library
The Dissociation Enthalpies of Terminal (N--O) Bonds in Organic Compounds (open access)

The Dissociation Enthalpies of Terminal (N--O) Bonds in Organic Compounds

Article on the dissociation enthalpies of terminal (N-O) bonds in organic compounds.
Date: May 27, 2005
Creator: Acree, William E. (William Eugene); Pilcher, Geoffrey & Silva, Maria D. M. C. Ribeiro da
System: The UNT Digital Library
Electron Cloud Build-up Study for DAFNE (open access)

Electron Cloud Build-up Study for DAFNE

After the first experimental observations compatible with the presence of the e-cloud effect in the DAFNE positron ring, a more systematic study has been performed regarding the e-cloud build-up. The measured field map of the magnetic field has been taken into account in the simulation for elements present in the four 10 m long bending sections, representing 40% of the whole positron ring. The obtained simulation results are presented together with the recent experimental observations performed on the vacuum behavior of the positron ring.
Date: May 27, 2005
Creator: Vaccarezza, C.; Cimino, R.; Drago, A.; Zobov, M.; Bellodi, G.; Schulte, D. et al.
System: The UNT Digital Library