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5.2 mW Single-Mode Power from a Coupled-Resonator Vertical-Cavity Laser (open access)

5.2 mW Single-Mode Power from a Coupled-Resonator Vertical-Cavity Laser

None
Date: November 28, 2000
Creator: Fischer, A. J.; Choquette, K. D.; Chow, W. W.; Allerman, A. A. & Geib, K. M.
System: The UNT Digital Library
8-(Hydroxymethyl)-3,N4-etheno-C, a potential carcinogenic glycidaldehyde product, miscodes in vitro using mammalian DNA polymerases (open access)

8-(Hydroxymethyl)-3,N4-etheno-C, a potential carcinogenic glycidaldehyde product, miscodes in vitro using mammalian DNA polymerases

None
Date: January 28, 2002
Creator: Singer, B.; Medina, Michael; Zhang, Yanbin; Wang, Zhigang; Guliaev, Anton B. & Hang, Bo
System: The UNT Digital Library
1985 EPRI/IIE Geothermal Conference and Workshop (open access)

1985 EPRI/IIE Geothermal Conference and Workshop

A report dedicated to the 1985 EPRI/IIE Geothermal Conference and Workshop
Date: June 28, 1985
Creator: unknown
System: The UNT Digital Library
2002 Gordon Research Conference on CATALYSIS. Final Progress Report (open access)

2002 Gordon Research Conference on CATALYSIS. Final Progress Report

The Gordon Research Conference (GRC) on CATALYSIS was held at Colby-Sawyer College from 6/23/02 thru 6/28/02. The Conference was well-attended with 118 participants. The attendees represented the spectrum of endeavor in this field coming from academia, industry, and government laboratories, both U.S. and foreign scientists, senior researchers, young investigators, and students.
Date: June 28, 2002
Creator: unknown
System: The UNT Digital Library
2009 Pilot Scale Fluidized Bed Steam Reforming Testing Using the Thor (Thermal Organic Reduction) Process: Analytical Results for Tank 48h Organic Destruction - 10408 (open access)

2009 Pilot Scale Fluidized Bed Steam Reforming Testing Using the Thor (Thermal Organic Reduction) Process: Analytical Results for Tank 48h Organic Destruction - 10408

The Savannah River Site (SRS) must empty the contents of Tank 48H, a 1.3 million gallon Type IIIA HLW storage tank, to return this tank to service. The tank contains organic compounds, mainly potassium tetraphenylborate that cannot be processed downstream until the organic components are destroyed. The THOR{reg_sign} Treatment Technologies (TTT) Fluidized Bed Steam Reforming (FBSR) technology, herein after referred to as steam reforming, has been demonstrated to be a viable process to remove greater than 99.9% of the organics from Tank 48H during various bench scale and pilot scale tests. These demonstrations were supported by Savannah River Remediation (SRR) and the Department of Energy (DOE) has concurred with the SRR recommendation to proceed with the deployment of the FBSR technology to treat the contents of Tank 48H. The Savannah River National Laboratory (SRNL) developed and proved the concept with non-radioactive simulants for SRR beginning in 2003. By 2008, several pilot scale campaigns had been completed and extensive crucible testing and bench scale testing were performed in the SRNL Shielded Cells using Tank 48H radioactive sample. SRNL developed a Tank 48H non-radioactive simulant complete with organic compounds, salt, and metals characteristic of those measured in a sample of the radioactive …
Date: December 28, 2009
Creator: Williams, M. R.; Jantzen, Carol M.; Burket, P. R.; Crawford, C. L.; Daniel, W. E.; Aponte, C. et al.
System: The UNT Digital Library
2nd Workshop on Satellites for Solar Energy Assessments (open access)

2nd Workshop on Satellites for Solar Energy Assessments

A Collection of Presentations on new techniques for developing climatological estimates of the solar resource at all locations on earth at a resolution of 100km, and of developing estimates at half-hour intervals at resolutions of 10 km or less in specific locations.
Date: June 28, 1999
Creator: Renne, D.
System: The UNT Digital Library
3C454.3 Revelas the Structure and Physics of its 'Blazar Zone' (open access)

3C454.3 Revelas the Structure and Physics of its 'Blazar Zone'

Recent multi-wavelength observations of 3C454.3, in particular during its giant outburst in 2005, put severe constraints on the location of the 'blazar zone', its dissipative nature, and high energy radiation mechanisms. As the optical, X-ray, and millimeter light-curves indicate, significant fraction of the jet energy must be released in the vicinity of the millimeter-photosphere, i.e. at distances where, due to the lateral expansion, the jet becomes transparent at millimeter wavelengths. We conclude that this region is located at {approx} 10 parsecs, the distance coinciding with the location of the hot dust region. This location is consistent with the high amplitude variations observed on {approx} 10 day time scale, provided the Lorentz factor of a jet is {Gamma}{sub j} {approx} 20. We argue that dissipation is driven by reconfinement shock and demonstrate that X-rays and {gamma}-rays are likely to be produced via inverse Compton scattering of near/mid IR photons emitted by the hot dust. We also infer that the largest gamma-to-synchrotron luminosity ratio ever recorded in this object - having taken place during its lowest luminosity states - can be simply due to weaker magnetic fields carried by a less powerful jet.
Date: November 28, 2007
Creator: Sikora, M.; Moderski, R. & Madejski, G.M.
System: The UNT Digital Library
3D field calculation of the GEM prototype magnet and comparison with measurements (open access)

3D field calculation of the GEM prototype magnet and comparison with measurements

The proposed 4 GeV Electron Microtron (GEM) is designed to fill the existing buildings left vacant by the demise of the Zero Gradient Synchrotron (ZGS) accelerator. One of the six large dipole magnets is shown as well as the first 10 electron orbits. A 3-orbit prototype magnet has been built. The stepped edge of the magnet is to keep the beam exiting perpendicular to the pole. The end guards that wrap around the main coils are joined together by the 3 shield plates. The auxiliary coils are needed to keep the end guards and shield plates from saturating. A 0.3 cm Purcell filter air gap exists between the pole and the yoke. Can anyone question this being a truly three-dimensional magnetostatic problem. The computer program TOSCA, developed at the Rutherford Appleton Laboratory by the Computing Applications Group, was used to calculate this magnet and the results have been compared with measurements.
Date: October 28, 1983
Creator: Lari, R.J.
System: The UNT Digital Library
3D finite-difference frequency-domain code for electromagnetic induction tomography (open access)

3D finite-difference frequency-domain code for electromagnetic induction tomography

The effect of shrapnel on target chamber components and experiments at large lasers such as the National Ignition Facility at LLNL and the Megajoule Laser at CESTA in France is an important issue in fielding targets and exposure samples. Modeling calculations are likely to be an important component of this effort. Some work in this area has been performed by French workers, who are collaborating with the LLNL on many issues relating to target chamber, experiment-component, and diagnostics survival. Experiments have been performed at the PhCbus laser in France to measure shrapnel produced by laser-driven targets; among these shots were experiments that accelerated spheres of a size characteristic of some of the more damaging shrapnel. These spheres were stopped in polyethylene witness plates. The penetration depth is characteristic of the velocity of the shrapnel. Experimental calibration of steel sphere penetration into polyethylene was performed at the CESTA facility. The penetration depth has been reported (ref. 1) and comparisons with modeling calculations have been made (ref. 2). There was interest in a comparison study of the modeling of these experiments to provide independent checks of the calculations. This work has been approved both by DOE headquarters and by the French Atomic …
Date: July 28, 1999
Creator: Berryman, J. G.; Champagne, N. J., II & Buettner, H. M.
System: The UNT Digital Library
3D Numerical Experimentation on the Core Helium Flash of Low-mass Red Giants (open access)

3D Numerical Experimentation on the Core Helium Flash of Low-mass Red Giants

None
Date: June 28, 2005
Creator: Dearborn, D. S. P.; Lattanzio, J. C. & Eggleton, P. P.
System: The UNT Digital Library
Absorption and Emission in the Non-Poissonian Case (open access)

Absorption and Emission in the Non-Poissonian Case

Article on absorption and emission in the Non-Poissonian Case.
Date: July 28, 2004
Creator: Aquino, Gerardo; Palatella, Luigi & Grigolini, Paolo
System: The UNT Digital Library
ABSTRACT: The Community Environmental Monitoring Program: Reducing Public Perception of Risk Through Stakeholder Involvement (open access)

ABSTRACT: The Community Environmental Monitoring Program: Reducing Public Perception of Risk Through Stakeholder Involvement

Between 1951 and 1992, 928 nuclear tests were conducted at the Nevada Test Site (NTS), including 100 atmospheric and 828 underground tests. Initial public reaction to the tests was largely supportive, but by the late 1950s this began to change, largely as a result of fear of the potential for adverse health effects to be caused by exposure to ionizing radiation resulting from the tests. The nuclear power plant accident at Three Mile Island in 1979 served to heighten these fears, as well as foster a general distrust of the federal agencies involved and low public confidence in monitoring results. Modeled after a similar program that involved the public in monitoring activities around the Three Mile Island nuclear power plant, the Community Environmental Monitoring Program (CEMP) has promoted stakeholder involvement, awareness, and understanding of radiological surveillance in communities surrounding the NTS since 1981. It involves stakeholders in the operation, data collection, and dissemination of information obtained from a network of 29 stations across a wide area of Nevada, Utah, and California. It is sponsored by the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office (NNSA/NSO) and administered by the Desert Research Institute (DRI) of the Nevada System …
Date: February 28, 2007
Creator: Hartwell, T.
System: The UNT Digital Library
Accelerating Thick Aluminum Liners Using Pulsed Power (open access)

Accelerating Thick Aluminum Liners Using Pulsed Power

The authors have investigated the acceleration of very thick cylindrical aluminum liners using the Pegasus II capacitory bank. These accelerated solid liners will be used to impact other objects at velocities below 1.5 km/sec, allowing one to generate and sustain shocks of a few 100 kilobar for a few microseconds. A cylindrical shell of 1100 series aluminum with an initial inner radius of 23.61 mm, an initial thickness of 3.0 mm, and a height of 20 mm, was accelerated using a current pulse of 7.15 MA peak current and a 7.4 microsecond quarter cycle time. The aluminum shell was imploded within confining copper glide planes with decreasing separation with an inward slope of 8 degrees. At impact with a cylindrical target of diameter 3-cm, the liner was moving at 1.4 km/sec and its thickness increased to 4.5 mm. Radial X-ray radiograms of the liner showed both the liner and the glide plane interface. The curvature of the inner surface of the liner was measured before impact with the 15-mm radius target. The radiograms also showed that the copper glide planes distorted as the liner radius decreased and that some axial stress is induced in the liner. The axial stresses did …
Date: June 28, 1999
Creator: Kyrala, George A.; Hammerburg, James E.; Bowers, David; Stokes, John; Morgan, Dane V.; Anderson, Wally E. et al.
System: The UNT Digital Library
Accelerator related backgrounds in the LHC forward detectors (open access)

Accelerator related backgrounds in the LHC forward detectors

Detailed Monte Carlo simulations are performed on radiation environment in the LHC IP5 interaction region at the locations of the TOTEM Roman Pots proposed to detect particles produced at very small angles in the elastic scattering and diffraction dissociation processes at the LHC. Radiation loads on these detectors are calculated with the MARS14 code both of the pp-collision origin and beam loss related (beam-gas and tails from collimators).
Date: May 28, 2003
Creator: al., Nikolai V. Mokhov et
System: The UNT Digital Library
Accountability methods for plutonium and uranium: the NRC manuals (open access)

Accountability methods for plutonium and uranium: the NRC manuals

Four manuals containing methods for the accountability of plutonium nitrate solutions, plutonium dioxide, uranium dioxide and mixed uranium-plutonium oxide have been prepared by us and issued by the U.S. Nuclear Regulatory Commission. A similar manual on methods for the accountability of uranium and plutonium in reprocessing plant dissolver solutions is now in preparation. In the present paper, we discuss the contents of the previously issued manuals and give a preview of the manual now being prepared.
Date: September 28, 1977
Creator: Gutmacher, R.G. & Stephens, F.B.
System: The UNT Digital Library
ACCUMULATION OF RADIOCESIUM BY MUSHROOMS IN THE ENVIRONMENT: A LITERATURE REVIEW (open access)

ACCUMULATION OF RADIOCESIUM BY MUSHROOMS IN THE ENVIRONMENT: A LITERATURE REVIEW

During the last 50 years, a large amount of information on radionuclide accumulators or ''sentinel-type'' organisms in the environment has been published. Much of this work focused on the risks of food-chain transfer of radionuclides to higher organisms such as reindeer and man. However, until the 1980's and 1990's, there has been little published data on the radiocesium ({sup 134}Cs and {sup 137}Cs) accumulation by mushrooms. This presentation will consist of a review of the published data for {sup 134,137}Cs accumulation by mushrooms in nature. This review will discuss the aspects that promote {sup 134,137}Cs uptake by mushrooms and focus on mushrooms that demonstrate a large propensity for use in the environmental biomonitoring of radiocesium contamination. It will also provide descriptions of habitats for many of these mushrooms and discuss on how growth media and other conditions relate to Cs accumulation.
Date: May 28, 2007
Creator: Duff, M
System: The UNT Digital Library
Accuracy of Reservoir Predictions for the Nesjavellir Geothermal Field, Iceland (open access)

Accuracy of Reservoir Predictions for the Nesjavellir Geothermal Field, Iceland

The performance of the 1986 three-dimensional numerical model of the Nesjavellir geothermal field for predicting the deliverabilities and pressure decline of the wells during the period 1987 through 1991 is investigated. The model predicted adequately the flow rate and enthalpy transients of most wells, but overpredicted the pressure decline by 3 to 4 bars.
Date: January 28, 1993
Creator: Bodvarsson, G. S.; Gislason, G.; Gunnlaugsson, E.; Sigurdsson, O.; Stefansson, V. & Steingrimsson,B.
System: The UNT Digital Library
Accuracy of single photoelectron time spread measurement of fast photomultipliers (open access)

Accuracy of single photoelectron time spread measurement of fast photomultipliers

None
Date: March 28, 1975
Creator: Leskovar, B.
System: The UNT Digital Library
Accurate wavelength measurements and modeling of FeXV to FeXIX spectra recorded in high density plasmas between 13.5 to 17 A. (open access)

Accurate wavelength measurements and modeling of FeXV to FeXIX spectra recorded in high density plasmas between 13.5 to 17 A.

Iron spectra have been recorded from plasmas created at three different laser plasma facilities, the Tor Vergata University laser in Rome (Italy), the Hercules laser at ENEA in Frascati (Italy), and the Compact Multipulse Terawatt (COMET) laser at LLNL in California (USA). The measurements provide a means of identifying dielectronic satellite lines from FeXVI and FeXV in the vicinity of the strong 2p {yields} 3d transitions of FeXVII. About 80 {Delta}n {ge} 1 lines of FeXV (Mg-like) to FeXIX (O-like) were recorded between 13.8 to 17.1 {angstrom} with a high spectral resolution ({lambda}/{Delta}{lambda} {approx} 4000), about thirty of these lines are from FeXVI and FeXV. The laser produced plasmas had electron temperatures between 100 to 500 eV and electron densities between 10{sup 20} to 10{sup 22} cm{sup -3}. The Hebrew University Lawrence Livermore Atomic Code (HULLAC) was used to calculate the atomic structure and atomic rates for FeXV to FeXIX. HULLAC was used to calculate synthetic line intensities at T{sub e} = 200 eV and n{sub e} = 10{sup 21}cm{sup -3} for three different conditions to illustrate the role of opacity: optically thin plasmas with no excitation-autoionization/dielectronic recombination (EA/DR) contributions to the line intensities, optically thin plasmas that included EA/DR …
Date: September 28, 2004
Creator: May, M.; Beiersdorfer, P.; Dunn, J.; Jordan, N.; Osterheld, A.; Faenov, A. et al.
System: The UNT Digital Library
Achieving and maintaining cleanliness in NIF amplifiers (open access)

Achieving and maintaining cleanliness in NIF amplifiers

Cleanliness measurements made on AMPLAB prototype National Ignition Facility (NIF) laser amplifiers during assembly, cassette transfer, and amplifier operation are summarized. These measurements include particle counts from surface cleanliness assessments using filter swipe techniques and from airborne particle monitoring. Results are compared with similar measurements made on the Beamlet and Nova lasers and in flashlamp test fixtures. Observations of Class 100,000 aerosols after flashlamp firings are discussed. Comparisons are made between typical damage densities on laser amplifier optics from Novette, NOVA, Beamlet, and AMPLAB.
Date: July 28, 1998
Creator: Burnham, A. K.; Horvath, J. A.; Letts, S. A.; Menapace, J. A. & Stowers, I. F.
System: The UNT Digital Library
Acid-Base Indicators: Transition Colours and pH Ranges Determined in Select Aqueous-Organic Mixed Solvents (open access)

Acid-Base Indicators: Transition Colours and pH Ranges Determined in Select Aqueous-Organic Mixed Solvents

Article on acid-base indicators and transition colours and pH ranges determined in select aqueous-organic mixed solvents.
Date: March 28, 1995
Creator: Tucker, Sheryl A. (Sheryl Ann); Bates, Heather C. & Acree, William E. (William Eugene)
System: The UNT Digital Library
Acquisition of building geometry in the simulation of energy performance (open access)

Acquisition of building geometry in the simulation of energy performance

Building geometry is essential to any simulation of building performance. This paper examines the importing of building geometry into simulation of energy performance from the users' point of view. It lists performance requirements for graphic user interfaces that input building geometry, and discusses the basic options in moving from two- to three-dimensional definition of geometry and the ways to import that geometry into energy simulation. The obvious answer lies in software interoperability. With the BLIS group of interoperable software one can interactively import building geometry from CAD into EnergyPlus and dramatically reduce the effort otherwise needed for manual input.The resulting savings may greatly increase the value obtained from simulation, the number of projects in which energy performance simulation is used, and expedite decision making in the design process.
Date: June 28, 2001
Creator: Bazjanac, Vladimir
System: The UNT Digital Library
Actinic imaging and evaluation of phase structures on EUV lithography masks (open access)

Actinic imaging and evaluation of phase structures on EUV lithography masks

The authors describe the implementation of a phase-retrieval algorithm to reconstruct phase and complex amplitude of structures on EUV lithography masks. Many native defects commonly found on EUV reticles are difficult to detect and review accurately because they have a strong phase component. Understanding the complex amplitude of mask features is essential for predictive modeling of defect printability and defect repair. Besides printing in a stepper, the most accurate way to characterize such defects is with actinic inspection, performed at the design, EUV wavelength. Phase defect and phase structures show a distinct through-focus behavior that enables qualitative evaluation of the object phase from two or more high-resolution intensity measurements. For the first time, phase of structures and defects on EUV masks were quantitatively reconstructed based on aerial image measurements, using a modified version of a phase-retrieval algorithm developed to test optical phase shifting reticles.
Date: September 28, 2010
Creator: Mochi, Iacopo; Goldberg, Kenneth & Huh, Sungmin
System: The UNT Digital Library
Actinide Biocolloid Formation in Brine by Halophilic Bacteria (open access)

Actinide Biocolloid Formation in Brine by Halophilic Bacteria

We examined the ability of a halophilic bacterium (WFP 1A) isolated from the Waste Isolation Pilot Plant (WIPP) site to accumulate uranium in order to determine the potential for biocolloid facilitated actinide transport. The bacterial cell Surface functional groups involved in the complexation of the actinide were determined by titration. Uranium, added as uranyl nitrate, was removed from solution at pH 5 by cells but at pH 7 and 9 very little uranium was removed due to its limited volubility. Although present as soluble species, uranyl citrate at pH 5, 7, and 9, and uranyl carbonate at pH 9 were not removed by the bacterium because they were not bioavailable due to their neutral or negative charge. Addition of uranyl EDTA to brine at pH 5, 7, and 9 resulted in the immediate precipitation of U. Transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS) analysis revealed that uranium was not only associated with the cell surface but also accumulated intracellulary as uranium-enriched granules. Extended X-ray absorption fine structure (EXAFS) analysis, of the bacterial cells indicated the bulk sample contained more than one uranium phase. Nevertheless these results show the potential for the formation of actinide bearing bacterial biocolloids …
Date: July 28, 1999
Creator: Gillow, J. B.; Francis, A. J.; Dodge, C. J.; Harris, R.; Beveridge, T. J.; Brady, P. V. et al.
System: The UNT Digital Library