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Aromatic C-H Activation and Catalytic Hydrophenylation of Ethylene by TpRu{P(OCH2)3CEt} (NCMe)Ph (open access)

Aromatic C-H Activation and Catalytic Hydrophenylation of Ethylene by TpRu{P(OCH2)3CEt} (NCMe)Ph

Article discussing aromatic C-H activation and catalytic hydrophenylation of ethylene by TpRu{P(OCH2)3CEt} (NCMe)Ph.
Date: June 5, 2008
Creator: Foley, Nicholas A.; Ke, Zhuofeng; Gunnoe, T. Brent; Cundari, Thomas R., 1964- & Petersen, Jeffrey L.
System: The UNT Digital Library
Charge transfer equilibria in ambient-exposed epitaxial graphene on (0001) 6 H-SiC (open access)

Charge transfer equilibria in ambient-exposed epitaxial graphene on (0001) 6 H-SiC

Article discussing research on charge transfer equilibria in ambient-exposed epitaxial graphene on (0001) 6 H-SiC.
Date: June 5, 2012
Creator: Sidorov, Anton N.; Gaskill, D. Kurt.; Buongiorno Nardelli, Marco; Tedesco, Joseph L.; Myers-Ward, Rachel L.; Eddy, Charles R. et al.
System: The UNT Digital Library
Cooperative Carbon Capture Capabilities in Multivariate MOFs Decorated with Amino Acid Side Chains: A Computational Study (open access)

Cooperative Carbon Capture Capabilities in Multivariate MOFs Decorated with Amino Acid Side Chains: A Computational Study

This article discusses cooperative carbon capture capabilities in metal organic frameworks decorated with amino acid side chains.
Date: June 5, 2013
Creator: Drummond, Michael L.; Cundari, Thomas R., 1964- & Wilson, Angela K.
System: The UNT Digital Library
Pharmacodynamics of potassium channel openers in cultured neuronal networks (open access)

Pharmacodynamics of potassium channel openers in cultured neuronal networks

Article discussing pharmacodynamics of potassium channel openers in cultured neuronal networks.
Date: June 5, 2014
Creator: Wu, Calvin; Gopal, Kamakshi V.; Lukas, Thomas J.; Gross, Guenter W. & Moore, Ernest J.
System: The UNT Digital Library
Facile, scalable synthesis of edge-halogenated graphene nanoplatelets as efficient metal-free eletrocatalysts for oxygen reduction reaction (open access)

Facile, scalable synthesis of edge-halogenated graphene nanoplatelets as efficient metal-free eletrocatalysts for oxygen reduction reaction

Article on facile, scalable synthesis of edge-halogenated graphene nanoplatelets as efficient metal-free electrocatalysts for oxygen reduction reaction.
Date: February 1, 2013
Creator: Jeon, In-Yup; Choi, Hyun-Jung; Choi, Min; Seo, Jeong-Min; Jung, Sun-Min; Kim, Min-Jung et al.
System: The UNT Digital Library
Comments on Solid-Liquid Phase Equilibrium and Phase Diagram for the Ternary o-Nitrobenzoic Acid + m-Nitrobenzoic Acid + Ethanol System (open access)

Comments on Solid-Liquid Phase Equilibrium and Phase Diagram for the Ternary o-Nitrobenzoic Acid + m-Nitrobenzoic Acid + Ethanol System

Article commenting on a paper published in 2008 in the Journal of Chemical and Engineering Data discussing solid-liquid phase equilibrium and phase diagram for the ternary o-nitrobenzoic acid + m-nitrobenzoic acid + ethanol system.
Date: June 5, 2009
Creator: Acree, William E. (William Eugene)
System: The UNT Digital Library
Removal of bird contamination in wind profiler signal spectra. (open access)

Removal of bird contamination in wind profiler signal spectra.

The problem of bird interference with radar performance is as old as radar itself; however, the problem specific to wind profiler operation has not drawn the attention of researchers until the last 5 or 6 years. Since then, the problem has been addressed in many publications and several ways to solve it have been indicated. Recent advances in radar hardware and software made the last generation of profilers much more immune to bird contamination. However, many older profilers are still in use; errors in averaged (hourly) winds due to bird interference may be as high as 15 m/s. The objective of the present study is to develop a practical method to derive mean winds from averaged spectral data of a 915-MHz wind profiler under the condition of bird contamination.
Date: June 5, 1998
Creator: Pekour, M. S.
System: The UNT Digital Library
The Argonne boundary layer experiments facility : using minisodars to complement a wind profiler network. (open access)

The Argonne boundary layer experiments facility : using minisodars to complement a wind profiler network.

The Argonne Boundary Layer Experiments (ABLE) facility, located in south central Kansas, east of Wichita, is devoted primarily to investigations of and within the planetary boundary layer (PBL), including the dynamics of the mixed layer during both day and night; effects of varying land use and land form; the interactive role of precipitation, runoff, and soil moisture; storm development; and energy budgets on scales of 10 to 100 km. Located entirely within the Walnut River watershed, ABLE provides intense measurements within the northeast quadrant (Fig. 1) of the Southern Great Plains (SGP) Cloud and Radiation Testbed (CART) of the Atmospheric Radiation Measurement (ARM) Program (Stokes and Schwarz, 1994). By combining the continuous measurements of ABLE with ancillary continuous measurements of, for example, the ARM and the Global Energy Water cycle Experiment (GEWEX) (Kinster and Shukla, 1990) programs, ABLE provides a platform within which shorter, more intensive studies, such as those conducted by the Cooperative Atmosphere-Surface Exchange Studies (CASES) Program, can realize the full benefit of a wide variety of atmospheric measurements on many scales; this allows the study of hypothesized features of PBL development and dynamics, including frontal dynamics, nocturnal boundary development and breakdown, urban heat island effects, precipitation enhancement, …
Date: June 5, 1998
Creator: Coulter, R. L.
System: The UNT Digital Library
Pore compressibility in rocks (open access)

Pore compressibility in rocks

The unjacketed core compressibility in a porous rock is the change in pore volume due to change in pore pressure for constant differential pressure. This parameter affects how the saturated bulk modulus of a rock is related to the drained frame modulus and the pore fluid compressibility. Recent measurements of poroelastic constants and effective medium theories are used to estimate how the pore compressibility depends on effective stress and how uncertainty in the pore compressibility affects uncertainty in Gassmann' equation estimates of the saturated bulk modulus. Results for Berea sandstone and for models of sand-clay mixtures show that the estimate of the change in the saturated bulk modulus due to substitution of different fluids in the rock may differ in size by a factor of two or more if the pore compressibility is approximately equal to the fluid compressibility instead of the grain compressibility. In general, the order of magnitude and sign of the pore compressibility cannot be determined from solid and fluid compressibility information alone.
Date: June 5, 1998
Creator: Berge, P A
System: The UNT Digital Library
Solute nucleation and growth in supercritical fluid mixtures (open access)

Solute nucleation and growth in supercritical fluid mixtures

This research effort is directed toward two primary scientific objectives: (1) to determine the gravitational effect on the measurement of nucleation and growth rates near a critical point and (2) to investigate the A nucleation process in supercritical fluids to aid in the evaluation and development of existing rheoretical models and practical applications. A nucleation pulse method will be employed for this investigation using a rapid expansion to a supersaturated state that is maintained for {approx}1 followed by a rapid recompression to a less supersaturated state that effectively terminates nucleation while permitting growth continue. Nucleation, which occurs during the initial supersaturated state, is decoupled from growth by producing rapid pressure changes. Thermodynamic analysis, condensation modeling, apparatus design, and optical diagnostic design necessary for the initiation of a theoretical and experimental investigation of naphthalene nucleation from supercritical CO{sub 2} have been completed.
Date: June 5, 1996
Creator: Smedley, G.T.; Rawlins, W.T. & Oakes, D.B.
System: The UNT Digital Library
Diagnostic development at LLNL for the National Ignition Facility (open access)

Diagnostic development at LLNL for the National Ignition Facility

ICF implosions at the NIF will produce core plasma temperatures in excess of 10-keV and densities of order 100 g/cm{sup 3}. Properties of these plasmas can be measured using a variety of optical, x-ray and nuclear techniques similar to those now in use at facilities such as Nova and Omega. Some of these techniques will be directly applicable on NIF while others, particularly the nuclear-based techniques, will change significantly.
Date: June 5, 1996
Creator: Sangster, T. C.; Cable, M. D.; Kilkenny, J. D. & Lerche, R. A.
System: The UNT Digital Library
Nuclear diagnostics in support of ICF experiments (open access)

Nuclear diagnostics in support of ICF experiments

As the yields of Inertial Confinement Fusion (ICF) experiments increase to NIF levels new diagnostic techniques for studying details of fusion burn behavior will become feasible. The new techniques will provide improved measurements of fusion burn temperature and history. Improved temperature measurements might be achieved with magnetic spectroscopy of fusion neutrons. High-bandwidth fusion reaction history will be measured with fusion-specific {gamma}-ray diagnostics. Additional energy-resolved {gamma}-ray might be able to study a selection of specific behaviors during fusion burn. Present ICF yields greater than 10{sup 13} neutrons are sufficient to demonstrate the basic methods that underlie the new techniques. As ICF yields increase, the diagnostics designs adjusted accordingly in order to provide clear and specific data on fusion burn performance.
Date: June 5, 1996
Creator: Moran, M. J. & Hall, J.
System: The UNT Digital Library
Neutron-induced noise in NIF-class diagnostic instruments (open access)

Neutron-induced noise in NIF-class diagnostic instruments

Neutron yields form DT-filled ICF targets have reached 10{sup 14}. Above 10{sup 13}, a significant neutron-induced background appears in images recorded with nearby streak cameras. Since cameras components (streak tube, image-intensifier tube, and CCD array) are similar to components that will be used in many NIF instruments, streak camera images provide information about neutron-induced backgrounds that will be encountered in the NIF environment. At a fluence of 10{sup 7} neutrons/cm{sup 2}, the background consists of two distinct components: a uniform component equal to nearly 20% of the camera`s linear range and sharp, intense peaks each localized to just a couple of image pixels. About 80% of the uniform background is caused by interactions with the streak tube and image-intensifier tube. Nearly all of the sharp spikes are caused by interactions with pixels of the CCD array. The spikes make the most significant contribution to image noise.
Date: June 5, 1996
Creator: Lerche, R.A.
System: The UNT Digital Library
Spatial filter lens design for the main laser of the National Ignition Facility (open access)

Spatial filter lens design for the main laser of the National Ignition Facility

The National Ignition Facility (NIF), being designed and constructed at Lawrence Livermore National Laboratory (LLNL), comprises 192 laser beams The lasing medium is neodymium in phosphate glass with a fundamental frequency (1{omega}) of 1 053{micro}m Sum frequency generation in a pair of conversion crystals (KDP/KD*P) will produce 1 8 megajoules of the third harmonic light (3{omega} or {lambda}=351{micro}m) at the target The purpose of this paper is to provide the lens design community with the current lens design details of the large optics in the Main Laser This paper describes the lens design configuration and design considerations of the Main Laser The Main Laser is 123 meters long and includes two spatial filters one 13 5 meters and one 60 meters These spatial filters perform crucial beam filtering and relaying functions We shall describe the significant lens design aspects of these spatial filter lenses which allow them to successfully deliver the appropriate beam characteristic onto the target For an overview of NIF please see ``Optical system design of the National Ignition Facility,`` by R Edward English. et al also found in this volume.
Date: June 5, 1998
Creator: Korniski, R. J., Optics 1 Inc, Westlake Village, CA
System: The UNT Digital Library
DOE integrated safeguards and security (DISS) system a nation-wide distributed information system for personnel security (open access)

DOE integrated safeguards and security (DISS) system a nation-wide distributed information system for personnel security

DISS uses secure client-server and relational database technology across open networks to address the problems of security clearance request processing and tracking of security clearances for the Department of energy. The system supports the entire process from data entry by the prospective clearance holders through tracking of all DOE clearances, and use of standard DOE badges in automated access control systems throughout the DOE complex.
Date: June 5, 1997
Creator: Block, B.
System: The UNT Digital Library
Fabrication process for the PEP II RF cavities (open access)

Fabrication process for the PEP II RF cavities

This paper presents the major steps used in the fabrication of the 26 RF Cavities required for the PEP-II B-factory. Several unique applications of conventional processes have been developed and successfully implemented: electron beam welding (EBW), with minimal porosity, of .75 inch (19 mm) copper cross-sections; extensive 5-axis milling of water channels; electroplating of .37 inch (10 mm) thick OFE copper; tuning of the cavity by profiling beam noses prior to final joining with the cavity body; and machining of the cavity interior, are described here.
Date: June 5, 1997
Creator: Franks, R.M.; Rimmer, R.A. & Schwarz, H.
System: The UNT Digital Library
A historical review of Waste Isolation Pilot Plant backfill development (open access)

A historical review of Waste Isolation Pilot Plant backfill development

Backfills have been part of Sandia National Laboratories' [Sandia's] Waste Isolation Pilot Plant [WIPP] designs for over twenty years. Historically, backfill research at Sandia has depended heavily on the changing mission of the WIPP facility. Early testing considered heat producing, high level, wastes. Bentonite/sand/salt mixtures were evaluated and studies focused on developing materials that would retard brine ingress, sorb radionuclides, and withstand elevated temperatures. The present-day backfill consists of pure MgO [magnesium oxide] in a pelletized form and is directed at treating the relatively low contamination level, non-heat producing, wastes actually being disposed of in the WIPP. Its introduction was motivated by the need to scavenging CO{sub 2} [carbon dioxide] from decaying organic components in the waste. However, other benefits, such as a substantial desiccating capacity, are also being evaluated. The MgO backfill also fulfills a statutory requirement for assurance measures beyond those needed to demonstrate compliance with the US Environmental Protection Agency [EPA] regulatory release limits. However, even without a backfill, the WIPP repository design still operates within EPA regulatory release limits.
Date: June 5, 2000
Creator: KRUMHANSL,JAMES L.; MOLECKE,MARTIN A.; PAPENGUTH,HANS W. & BRUSH,LAURENCE H.
System: The UNT Digital Library
A process model of natural attenuation in drainage from a historic mining district (open access)

A process model of natural attenuation in drainage from a historic mining district

A process model was used to better understand the controls on the chemical evolution of drainage in a historic mining district. At the Pecos Mine Operable Unit, New Mexico, drainage near the waste rock pile is acidic (pH varies from 3.0--5.0) and carries high concentrations of Zn, Al, Cu and Pb. As drainage flows toward the Pecos River, pH increases to greater than 7 and heavy metal content decreases. A process model of natural attenuation in this drainage shows the main controls on pH are reaction with a local bedrock that contains limestone, and concurrent mixing with tributary streams. Models that account for both calcite dissolution and mixing reproduce the observed decrease in aqueous metal concentrations with increasing pH. Contaminant concentrations attenuate primarily via two distinct pathways: Al, Cu, Fe and Pb precipitate directly from solution, whereas Zn, Mg, Mn and SO{sub 4} concentrations decrease primarily through dilution. Additionally, Pb adsorbs to precipitating hydroxide surfaces.
Date: June 5, 2000
Creator: BERGER,AMY C.; BETHKE,CRAIG M. & KRUMHANSL,JAMES L.
System: The UNT Digital Library
From science to compliance: Geomechanics studies of the Waste Isolation Pilot Plant (open access)

From science to compliance: Geomechanics studies of the Waste Isolation Pilot Plant

Mechanical and hydrological properties of salt provide excellent bases for geological isolation of hazardous materials. Regulatory certification of the Waste Isolation Pilot Plant (WIPP) testifies to the nearly ideal characteristics of bedded salt deposits in southeast New Mexico. The WIPP history includes decades of testing and scientific investigations, which have resulted in a comprehensive understanding of salt's mechanical deformational and hydrological properties over an applicable range of stresses and temperatures. Comprehensive evaluation of salt's favorable characteristics helped demonstrate regulatory compliance and ensure isolation of radioactive waste placed in a salt geological setting.
Date: June 5, 2000
Creator: HANSEN,FRANCIS D.
System: The UNT Digital Library
Room Temperature Continuous Wave InGaSsN Quantum Well Vertical Cavity Lasers Emitting at 1.3 um (open access)

Room Temperature Continuous Wave InGaSsN Quantum Well Vertical Cavity Lasers Emitting at 1.3 um

Selectively oxidized vertical cavity lasers emitting at 1294 nm using InGaAsN quantum wells are reported for the first time which operate continuous wave at and above room temperature. The lasers employ two n-type Al{sub 0.94}Ga{sub 0.06}As/GaAs distributed Bragg reflectors each with a selectively oxidized current aperture adjacent to the optical cavity, and the top output mirror contains a tunnel junction to inject holes into the active region. Continuous wave single mode lasing is observed up to 55 C. These lasers exhibit the longest wavelength reported to date for vertical cavity surface emitting lasers grown on GaAs substrates.
Date: June 5, 2000
Creator: Choquette, Kent D.; Klem, John F.; Fischer, Arthur J.; Spahn, Olga B.; Allerman, Andrew A.; Fritz, Ian J. et al.
System: The UNT Digital Library
Developing ''SMART'' equipment and systems through collaborative NERI research and development (open access)

Developing ''SMART'' equipment and systems through collaborative NERI research and development

The United States Department of Energy initiated the Nuclear Energy Research Initiative (NERI) to conduct research and development with the objectives of: (1) overcoming the principal technical obstacles to expanded nuclear energy use, (2) advancing the state of nuclear technology to maintain its competitive position in domestic and world markets, and (3) improving the performance, efficiency, reliability, and economics of nuclear energy. Fiscal Year 1999 program funding is $19 Million, with increased finding expected for subsequent years, emphasizing international cooperation. Among the programs selected for funding is the ``Smart Equipment and Systems to Improve Reliability and Safety in Future Nuclear Power Plant Operations''. This program is a 30 month collaborative effort bringing together the technical capabilities of ABB C-E Nuclear Power, Inc. (ABB CENP), Sandia National Laboratories, Duke Engineering and Services (DE and S), Massachusetts Institute of Technology (MIT) and Pennsylvania State University (PSU). The program's goal is to design, develop and evaluate an integrated set of smart equipment and predictive maintenance tools and methodologies that will significantly reduce nuclear plant construction, operation and maintenance costs. To accomplish this goal the Smart Equipment program will: (1) Identify and prioritize nuclear plant equipment that would most likely benefit from adding smart …
Date: June 5, 2000
Creator: Harmon, Daryl L.; Chapman, Leon D.; Golay, Michael W.; Maynard, Kenneth P. & Spencer, Joseph W.
System: The UNT Digital Library
Analysis of Enriched Uranium and Weapons Plutonium Reloads for PWRs Using BRACC (open access)

Analysis of Enriched Uranium and Weapons Plutonium Reloads for PWRs Using BRACC

Comparisons of the multicycle results demonstrate that the correlation coefficients based on the CASMO3 data were implemented correctly and that the Linear Reactivity Model is acceptably accurate for missed reloads containing both uranium and weapons plutonium fuel. The expanded set of correlation coefficients make BRACC a useful tool for performing multi-cycle in-core fuel management studies of PWR cores containing weapons plutonium.
Date: June 5, 1997
Creator: Alonso, G. & Parish, T. A.
System: The UNT Digital Library
Mathematical and Numerical Approaches in Performance Assessment for Radioactive Waste Disposal: Dealing with Uncertainty (open access)

Mathematical and Numerical Approaches in Performance Assessment for Radioactive Waste Disposal: Dealing with Uncertainty

None
Date: June 5, 2000
Creator: HELTON,JON CRAIG
System: The UNT Digital Library
Correlating Observations of Deformation Microstructures by TEM and Automated EBSD Techniques (open access)

Correlating Observations of Deformation Microstructures by TEM and Automated EBSD Techniques

The evolution of the deformed microstructure as a function of imposed plastic strain is of interest as it provides information on the material hardening characteristics and mechanism(s) by which cold work energy is stored. This has been extensively studied using transmission electron microscopy (TEM), where the high spatial and orientational resolution of the technique is used to advantage to study local phenomenon such as dislocation core structures and interactions of dislocations. With the recent emergence of scanning electron microscope (SEM) based automated electron backscatter diffraction (EBSD) techniques, it has now become possible to make mesoscale observations that are statistical in nature and complement the detailed TEM observations. Correlations of such observations will be demonstrated for the case of Ni-base alloys, which are typically non-cell forming solid solution alloys when deformed at ambient temperatures. For instance, planar slip is dominant at low strain levels but evolves into a microstructure where distinct crystallographic dislocation-rich walls form as a function of strain and grain orientation. Observations recorded using both TEM and EBSD techniques are presented and analyzed for their implication on subsequent annealing characteristics.
Date: June 5, 2000
Creator: Schwartz, A.J. & King, W.E.
System: The UNT Digital Library