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Enthalpy of Solvation Correlations for Organic Solutes and Gases Dissolved in 1-Propanol and Tetrahydrofuran (open access)

Enthalpy of Solvation Correlations for Organic Solutes and Gases Dissolved in 1-Propanol and Tetrahydrofuran

This article discusses the enthalpy of solvation correlations for organic solutes and gases dissolved in 1-propanol and tetrahydrofuran.
Date: May 20, 2011
Creator: Stephens, Timothy W.; Chou, Vicky; Quay, Amanda N.; Acree, William E. (William Eugene) & Abraham, M. H. (Michael H.)
System: The UNT Digital Library
Barriers to Pain Management: Caregiver Perceptions and Pain Talk by Hospice Interdisciplinary Teams (open access)

Barriers to Pain Management: Caregiver Perceptions and Pain Talk by Hospice Interdisciplinary Teams

Article on caregiver perceptions, pain talk by hospice interdisciplinary teams, and barriers to pain management.
Date: May 20, 2008
Creator: Oliver, Debra Parker; Wittenberg-Lyles, Elaine; Demiris, George; Washington, Karla T.; Porock, Davina, Ph. D. & Day, Michele L.
System: The UNT Digital Library
Kinetic studies of the reactions of hydroxyl radicals with the methyl-substituted silanes SiHn (CH₃)₄-n (n=0 to 4) at room temperature (open access)

Kinetic studies of the reactions of hydroxyl radicals with the methyl-substituted silanes SiHn (CH₃)₄-n (n=0 to 4) at room temperature

Article on kinetic studies of the reactions of hydroxyl radicals with the methyl-substituted silanes SiHn (CH3)4-n (n=0 to 4) at room temperature.
Date: May 20, 2003
Creator: Goumri, Abdellatif; Yuan, Jessie; Hommel, Elizabeth L. & Marshall, Paul
System: The UNT Digital Library
POLARIZED PROTONS TRACKING IN THE AGS AND RHIC. (open access)

POLARIZED PROTONS TRACKING IN THE AGS AND RHIC.

A code, SPINK, to track polarized particles in a circular accelerator, in particular RHIC [1], is been used to: find conditions for safely crossing depolarizing resonances, using Siberian Snakes; find the best conditions to match the spin of the injected beam to the ring lattice; study the operation of Spin Rotators and study the beam-beam effects in a polarized proton collider.
Date: May 20, 1999
Creator: Luccio, A. U.
System: The UNT Digital Library
Dissolution test for low-activity waste product acceptance. (open access)

Dissolution test for low-activity waste product acceptance.

We have measured the mean and standard deviation of the solution concentrations of B, Na, and Si attained in replicate dissolution tests conducted at temperatures of 20, 40, and 70 C, for durations of 3 and 7 days, and at glass/water mass ratios of 1:10 and 1:1. These and other tests were conducted to evaluate the adequacy of the test methods specified in privatization contracts and to develop a data base that can be used to evaluate the reliability of reported results for tests performed on the waste products. Tests were conducted with a glass that we formulated to be similar to low-activity waste products that will be produced during the remediation of Hanford tank wastes. Statistical analyses indicated that, while the mean concentrations of B, Na, and Si were affected by the values of test parameters, the standard deviation of replicate tests was not. The precision of the tests was determined primarily by uncertainties in the analysis of the test solutions. Replicate measurements of other glass properties that must be reported for Hanford low-activity waste products were measured to evaluate the possible adoption of the glass used in these tests as a standard test material for the product acceptance …
Date: May 20, 1998
Creator: Ebert, W. L.
System: The UNT Digital Library
18th U.S. Department of Energy Low-Level Radioactive Waste Management Conference. Program (open access)

18th U.S. Department of Energy Low-Level Radioactive Waste Management Conference. Program

This conference explored the latest developments in low-level radioactive waste management through presentations from professionals in both the public and the private sectors and special guests. The conference included two continuing education seminars, a workshop, exhibits, and a tour of Envirocare of Utah, Inc., one of America's three commercial low-level radioactive waste depositories.
Date: May 20, 1997
Creator: unknown
System: The UNT Digital Library
Experience With Polarized Proton Acceleration at Cosy (Julich) (open access)

Experience With Polarized Proton Acceleration at Cosy (Julich)

The Cooler Synchrotrons and storage ring COSY at the Forschungszentrum Juelich accelerates protons to momenta between 600 MeV/c and 3300 MeV/c [2]. At present the beam is used at four internal and three external target places. In addition, a polarized beam can be produced and accelerated at COSY. A colliding beams source, developed by a collaboration of the universities of Bonn, Erlangen, and Cologne is in operation [3]. The polarized H{sup {minus}} beam delivered by this source is pre-accelerated in a cyclotron to 295 MeV/c and injected via stripping injection into the COSY ring. The polarization of the circulating proton beam in COSY is measured continuously during acceleration with the internal EDDA detector [4]. In this paper the methods to overcome depolarizing resonances in COSY are discussed and the progress to preserve polarization during acceleration is presented.
Date: May 20, 1999
Creator: Lehrach, A.
System: The UNT Digital Library
Parallelization of an unstructured grid, hydrodynamic-diffusion code (open access)

Parallelization of an unstructured grid, hydrodynamic-diffusion code

We describe the parallelization of a three dimensional, un structured grid, finite element code which solves hyperbolic conservation laws for mass, momentum, and energy, and diffusion equations modeling heat conduction and radiation transport. Explicit temporal differencing advances the cell-based gasdynamic equations. Diffusion equations use fully implicit differencing of nodal variables which leads to large, sparse, symmetric, and positive definite matrices. Because of the unstructured grid, the off-diagonal non-zero elements appear in unpredictable locations. The linear systems are solved using parallelized conjugate gradients. The code is parailelized by domain decomposition of physical space into disjoint subdomains (SDS). Each processor receives its own SD plus a border of ghost cells. Results are presented on a problem coupling hydrodynamics to non-linear heat cond
Date: May 20, 1998
Creator: Milovich, J L & Shestakov, A
System: The UNT Digital Library
Development of an expert system for transportation of hazardous and radioactive materials (open access)

Development of an expert system for transportation of hazardous and radioactive materials

Under the sponsorship of the US Department of Energy`s (DOE`s) Transportation Management Division (EM-261), the Transportation Technologies Group at Oak Ridge National Laboratory (ORNL) has designed and developed an expert system prototype application of the hazardous materials transportation regulations. The objective of this task was to provide a proof-of-concept for developing a computerized expert system that will ensure straightforward, consistent, and error-free application of the hazardous materials transportation regulations. The expert system prototype entailed the analysis of what an expert in hazardous materials shipping information could/should do. From the analysis of the different features required for the expert system prototype, it was concluded that the developmental efforts should be directed to a Windows{trademark} 3.1 hypermedia environment. Hypermedia technology usually works as an interactive software system that gives personal computer users the ability to organize, manage, and present information in a number of formats--text, graphics, sound, and full-motion video.
Date: May 20, 1994
Creator: Ferrada, J. J.; Michelhaugh, R. D. & Rawl, R. R.
System: The UNT Digital Library
Techniques and results of tokamak-edge simulation (open access)

Techniques and results of tokamak-edge simulation

This paper describes recent development of the UEDGE code in three important areas. (1) Non-orthogonal grids allow accurate treatment of experimental geometries in which divertor plates intersect flux surfaces at oblique angles. (2) Radating impurities are included by means of one or more continuity equations that describe transport and sources, and sinks due to ionization and recombination processes. (3) Advanced iterative methods that reduce storage and execution time allow us to find fully converged solutions of larger problems (i.e., finer grids). Sample calculations are presented to illustrate these development.
Date: May 20, 1994
Creator: Smith, G. R.; Brown, P. N.; Rensink, M. E.; Rognlien, T. D.; Campbell, R. B.; Knoll, D. A. et al.
System: The UNT Digital Library
Greenhouse gas emission impacts of alternative-fueled vehicles: Near-term vs. long-term technology options (open access)

Greenhouse gas emission impacts of alternative-fueled vehicles: Near-term vs. long-term technology options

Alternative-fueled vehicle technologies have been promoted and used for reducing petroleum use, urban air pollution, and greenhouse gas emissions. In this paper, greenhouse gas emission impacts of near-term and long-term light-duty alternative-fueled vehicle technologies are evaluated. Near-term technologies, available now, include vehicles fueled with M85 (85% methanol and 15% gasoline by volume), E85 (85% ethanol that is produced from corn and 15% gasoline by volume), compressed natural gas, and liquefied petroleum gas. Long-term technologies, assumed to be available around the year 2010, include battery-powered electric vehicles, hybrid electric vehicles, vehicles fueled with E85 (ethanol produced from biomass), and fuel-cell vehicles fueled with hydrogen or methanol. The near-term technologies are found to have small to moderate effects on vehicle greenhouse gas emissions. On the other hand, the long-term technologies, especially those using renewable energy (such as biomass and solar energy), have great potential for reducing vehicle greenhouse gas emissions. In order to realize this greenhouse gas emission reduction potential, R and D efforts must continue on the long-term technology options so that they can compete successfully with conventional vehicle technology.
Date: May 20, 1997
Creator: Wang, M.Q.
System: The UNT Digital Library
Inelastic Constitutive Properties and shear Localization in Tennessee Marble (open access)

Inelastic Constitutive Properties and shear Localization in Tennessee Marble

Shear bands and faults are ubiquitous features of brittle rock deformation at a variety of length scales. Despite the prevalence of these features, understandhg of their inception remains rudimentary. Laboratory experiments suggest a casual association of localization of deformation (faulting) with peak stress, but more detailed examination reveals that localization can precede or follow the peak. Rudnicki and Rice (1975, hereafter abbreviated as RR) have suggested a the- ory of the inception of localization as a bifurcation or nonuniqueness of the so- lution for homogeneous deformation. They predict a strong dependence of local- ization on deformation state. In particular, they predict that localization can occur prepeak for deformation states near deviatoric pure shear and does not occur until well after peak for axisymmetric compression. This prediction is roughly in ac- cord with the true triaxial experiments of Mogi (1967, 1971). More recently, Ord et al. (1991) and Wwersik et al. (1991) have reported observations of localization prior to peak stress in plane strain experiments. The predictions of RR depend strongly on the constitutive properties of the rock and detailed comparison has been impeded by inadequate knowledge of those properties. Even the idealized constitutive model used by RR requires knowledge of …
Date: May 20, 1999
Creator: Holcomb, David J. & Rudnicki, J.W.
System: The UNT Digital Library
The Role of Conversation Policy in Carrying Out Agent Conversations (open access)

The Role of Conversation Policy in Carrying Out Agent Conversations

Structured conversation diagrams, or conversation specifications, allow agents to have predictable interactions and achieve predefined information-based goals, but they lack the flexibility needed to function robustly in an unpredictable environment. We propose a mechanism that combines a typical conversation structure with a separately established policy to generate an actual conversation. The word "policy" connotes a high-level direction external to a specific planned interaction with the environment. Policies, which describe acceptable procedures and influence decisions, can be applied to broad sets of activity. Based on their observation of issues related to a policy, agents may dynamically adjust their communication patterns. The policy object describes limitations, constraints, and requirements that may affect the conversation in certain circumstances. Using this new mechanism of interaction simplifies the description of individual conversations and allows domain-specific issues to be brought to bear more easily during agent communication. By following the behavior of the conversation specification when possible and deferring to the policy to derive behavior in exceptional circumstances, an agent is able to function predictably under normal situations and still act rationally in abnormal situations. Different conversation policies applied to a given conversation specification can change the nature of the interaction without changing the specification.
Date: May 20, 1999
Creator: Link, Hamilton E. & Phillips, Laurence R.
System: The UNT Digital Library
Non-Classical Smoothening of Nano-Scale Surface Corrugations (open access)

Non-Classical Smoothening of Nano-Scale Surface Corrugations

We report the first experimental observation of non-classical morphological equilibration of a corrugated crystalline surface. Periodic rippled structures with wavelengths of 290-550 nm were made on Si(OO1) by sputter rippling and then annealed at 650 - 750 &deg;C. In contrast to the classical exponential decay with time, the ripple amplitude, A<sub>{lambda}</sub>(t), followed an inverse linear decay, A<sub>{lambda}</sub>(t)= A<sub>{lambda}</sub>(0)/(1 +k<sub>{lambda}</sub>t), agreeing with a prediction of Ozdemir and Zangwill. We measure the activation energy for surface relaxation to be 1.6&plusmn;0.2 eV, consistent with an interpretation that dimers mediate transport.
Date: May 20, 1999
Creator: Aziz, Michael J.; Chason, Eric; Erlebacher, Jonah; Floro, Jerrold A. & Sinclair, Michael B.
System: The UNT Digital Library
QCD constraints on form factor shapes (open access)

QCD constraints on form factor shapes

This talk presents an introduction to the use of dispersion relations to constrain the shapes of hadronic form factors consistent with QCD. The applications described include methods for studying the strange quark mass,and the pion charge ratio.
Date: May 20, 1999
Creator: Lebed, R.F.
System: The UNT Digital Library
Searching for X(5) behavior in nuclei (open access)

Searching for X(5) behavior in nuclei

None
Date: May 20, 2003
Creator: Clark, Rod M.; Cromaz, Mario A.; Deleplanque, Marie-Agnes; Descovich, Martina; Diamond, Richard M.; Fallon, Paul et al.
System: The UNT Digital Library
The distant type Ia supernova rate (open access)

The distant type Ia supernova rate

We present a measurement of the rate of distant Type Ia supernovae derived using 4 large subsets of data from the Supernova Cosmology Project. Within this fiducial sample,which surveyed about 12 square degrees, thirty-eight supernovae were detected at redshifts 0.25--0.85. In a spatially flat cosmological model consistent with the results obtained by the Supernova Cosmology Project, we derive a rest-frame Type Ia supernova rate at a mean red shift z {approx_equal} 0.55 of 1.53 {sub -0.25}{sub -0.31}{sup 0.28}{sup 0.32} x 10{sup -4} h{sup 3} Mpc{sup -3} yr{sup -1} or 0.58{sub -0.09}{sub -0.09}{sup +0.10}{sup +0.10} h{sup 2} SNu(1 SNu = 1 supernova per century per 10{sup 10} L{sub B}sun), where the first uncertainty is statistical and the second includes systematic effects. The dependence of the rate on the assumed cosmological parameters is studied and the redshift dependence of the rate per unit comoving volume is contrasted with local estimates in the context of possible cosmic star formation histories and progenitor models.
Date: May 20, 2002
Creator: Pain, R.; Fabbro, S.; Sullivan, M.; Ellis, R. S.; Aldering, G.; Astier, P. et al.
System: The UNT Digital Library
Mitigation of the electron-cloud effect in the PSR and SNS proton storage rings by tailoring the bunch profile (open access)

Mitigation of the electron-cloud effect in the PSR and SNS proton storage rings by tailoring the bunch profile

For the storage ring of the Spallation Neutron Source(SNS) at Oak Ridge, and for the Proton Storage Ring (PSR) at Los Alamos, both with intense and very long bunches, the electroncloud develops primarily by the mechanism of trailing-edge multipacting. We show, by means of simulations for the PSR, how the resonant nature of this mechanism may be effectively broken by tailoring the longitudinal bunch profile at fixed bunch charge, resulting in a significant decrease in the electron-cloud effect. We briefly discuss the experimental difficulties expected in the implementation of this cure.
Date: May 20, 2003
Creator: Pivi, M. & Furman, M. A.
System: The UNT Digital Library
Use of projectional phase space data to infer a 4D particle distribution (open access)

Use of projectional phase space data to infer a 4D particle distribution

We consider beams which are described by a 4D transverse distribution f(x,y,x{prime},y{prime}), where x{prime} {triple_bond} p{sub x}/p{sub z} and z is the axial coordinate. A two-slit scanner is commonly employed to measure, over a sequence of shots, a 2D projection of such a beam's phase space, e.g., f(x,x{prime}). Another scanner might yield f(y,y{prime}) or, using crossed slits, f(x,y). A small set of such 2D scans does not uniquely specify f(x,y,x{prime},y{prime}). We have developed ''tomographic'' techniques to synthesize a ''reasonable'' set of particles in a 4D phase space having 2D densities consistent with the experimental data. These techniques are described in a separate document [A. Friedman, et. al., submitted to Phys. Rev. ST-AB, 2002]. Here we briefly summarize one method and describe progress in validating it, using simulations of the High Current Experiment at Lawrence Berkeley National Laboratory.
Date: May 20, 2002
Creator: Friedman, A.; Grote, D. P.; Celata, C. M. & Staples, J. W.
System: The UNT Digital Library
A 1.8 Mev K+ injector for the high current beam transport experiment fusion (open access)

A 1.8 Mev K+ injector for the high current beam transport experiment fusion

For the High Current Beam Transport Experiment (HCX) at LBNL, an injector is required to deliver up to 1.8 MV of 0.6 A K{sup +} beam with an emittance of {approx}1 p-mm-mrad. We have successfully operated a 10-cm diameter surface ionization source together with an electrostatic quadrupole (ESQ) accelerator to meet these requirements. The pulse length is {approx}4 {micro}s, firing at once every 10-15 seconds. By optimizing the extraction diode and the ESQ voltages, we have obtained an output beam with good current density uniformity, except for a small increase near the beam edge. Characterization of the beam emerging from the injector included measurements of the intensity profile, beam imaging, and transverse phase space. These data along with comparison to computer simulations provide the knowledge base for designing and understanding future HCX experiments.
Date: May 20, 2002
Creator: Kwan, J. W.; Bieniosek, F. M.; Henestroza, E.; Prost, L. & Seidl, P.
System: The UNT Digital Library
Klystron 'efficiency loop' for the ALS storage ring RF system (open access)

Klystron 'efficiency loop' for the ALS storage ring RF system

The recent energy crisis in California has led us to investigate the high power RF systems at the Advanced Light Source (ALS) in order to decrease the energy consumption and power costs. We found the Storage Ring Klystron Power Amplifier system operating as designed but with significant power waste. A simple proportional-integrator (PI) analog loop, which controls the klystron collector beam current, as a function of the output RF power, has been designed and installed. The design considerations, besides efficiency improvement, were to interface to the existing system without major expense. They were to also avoid the klystron cathode power supply filter's resonance in the loop's dynamics, and prevent a conflict with the existing Cavity RF Amplitude Loop dynamics. This efficiency loop will allow us to save up to 700 MW-hours of electrical energy per year and increase the lifetime of the klystron.
Date: May 20, 2002
Creator: Kwiatkowski, Slawomir; Julian, Jim & Baptiste, Kenneth
System: The UNT Digital Library
Studies of grain boundaries in melt textured YBa{sub 2}Cu{sub 3}O{sub x}. (open access)

Studies of grain boundaries in melt textured YBa{sub 2}Cu{sub 3}O{sub x}.

[001] tilt grain boundaries were studied in bi-crystal samples of melt textured YBa{sub 2}Cu{sub 3}O{sub x}. Grain boundary critical current densities J{sub CB} were obtained from SQUID magnetization measurements on ring samples that contain the grain boundary. The dependence of J{sub CB} on oxygen stoichiometry and oxygen ordering were investigated and preliminary studies of grain boundary doping with selected cations, including Ca, Sr, and Bi were undertaken.
Date: May 20, 2002
Creator: Veal, B. W.; Claus, H.; Chen, L. & Paulikas, A. P.
System: The UNT Digital Library
When a Rose Is Not a Rose: A Review of Recent Estimates of Congestion Costs (open access)

When a Rose Is Not a Rose: A Review of Recent Estimates of Congestion Costs

None
Date: May 20, 2004
Creator: Lesieutre, Bernard C. & Eto, Joseph H.
System: The UNT Digital Library
Subcellular Proteomic Analysis of Host-Pathogen Interactions Using Human Monocytes Exposed to Yersinia Pestis and Yersinia Pseudotuberculosis (open access)

Subcellular Proteomic Analysis of Host-Pathogen Interactions Using Human Monocytes Exposed to Yersinia Pestis and Yersinia Pseudotuberculosis

Yersinia pestis, the etiological agent of plague, is of concern to human health both from an infectious disease and a civilian biodefense perspective. While Y. pestis and Y. pseudotuberculosis share more than 90% DNA homology, they have significantly different clinical manifestations. Plague is often fatal if untreated, yet Y. pseudotuberculosis causes severe intestinal distress and is rarely fatal. A better understanding of host response to these closely related pathogens may help explain the different mechanisms of virulence and pathogenesis that result in such different clinical outcomes. The aim of this study was to characterize host protein expression changes in human monocyte-like U937 cells after exposure to Y. pestis and Y. pseudotuberculosis. In order to gain global proteomic coverage of host response, proteins from cytoplasmic, nuclear and membrane fractions of host cells were studied by 2-dimensional differential gel electrophoresis (2-D DIGE) and relative protein expression differences were quantitated. Differentially expressed proteins, with at least 1.5 fold expression changes and p values of 0.01 or less, were identified by MALDI-MS or LC/MS/MS. With these criteria, differential expression was detected in 16 human proteins after Y. pestis exposure and 13 human proteins after Y. pseudotuberculosis exposure, of which only two of the differentially …
Date: May 20, 2004
Creator: Zhang, C. G.; Gonzales, A. D.; Choi, M. W.; Chromy, B. A.; Fitch, J. P. & McCutchen-Maloney, S. L.
System: The UNT Digital Library