Sanitary Landfill Groundwater Monitoring Report (Data Only) - First Quarter 1999 (open access)

Sanitary Landfill Groundwater Monitoring Report (Data Only) - First Quarter 1999

This report contains analytical data for samples taken during First Quarter 1999 from wells of the LFW series located at the Sanitary Landfill at the Savannah River Site (SRS). This report presents monitoring results that equaled or exceeded the Safe Drinking Water Act final Primary Drinking Water Standards or screening levels, established by the U.S. Environmental Proteciton Agency, the South Carolina final Primary Drinking Water Standard for lead, or the SRS flagging criteria.
Date: May 26, 1999
Creator: Chase, J.
Object Type: Report
System: The UNT Digital Library
Endothelial Cell Migration and Vascular Endothelial Growth Factor Expression Are the Result of Loss of Breast Tissue Polarity (open access)

Endothelial Cell Migration and Vascular Endothelial Growth Factor Expression Are the Result of Loss of Breast Tissue Polarity

Recruiting a new blood supply is a rate-limiting step in tumor progression. In a three-dimensional model of breast carcinogenesis, disorganized, proliferative transformed breast epithelial cells express significantly higher expression of angiogenic genes compared with their polarized, growth-arrested nonmalignant counterparts. Elevated vascular endothelial growth factor (VEGF) secretion by malignant cells enhanced recruitment of endothelial cells (EC) in heterotypic cocultures. Significantly, phenotypic reversion of malignant cells via reexpression of HoxD10, which is lost in malignant progression, significantly attenuated VEGF expression in a hypoxia-inducible factor 1{alpha}-independent fashion and reduced EC migration. This was due primarily to restoring polarity: forced proliferation of polarized, nonmalignant cells did not induce VEGF expression and EC recruitment, whereas disrupting the architecture of growth-arrested, reverted cells did. These data show that disrupting cytostructure activates the angiogenic switch even in the absence of proliferation and/or hypoxia and restoring organization of malignant clusters reduces VEGF expression and EC activation to levels found in quiescent nonmalignant epithelium. These data confirm the importance of tissue architecture and polarity in malignant progression.
Date: May 26, 2009
Creator: Chen, Amy; Cuevas, Ileana; Kenny, Paraic A; Miyake, Hiroshi; Mace, Kimberley; Ghajar, Cyrus et al.
Object Type: Article
System: The UNT Digital Library
Strain-dependent photoluminescence behavior in three geometries of CdSe/CdS nanocrystals (open access)

Strain-dependent photoluminescence behavior in three geometries of CdSe/CdS nanocrystals

In recent years, a new generation of quantum confined colloidal semiconductor structures has emerged, with more complex shapes than simple quantum dots1, 2. These include nanorods3 and tetrapods4. Beyond shape, it is also now possible to spatially vary the electron and hole potentials within these nanoparticles by varying the composition. Examples of these new structures include seeded dots, rods, and tetrapods, which contain a CdSe core embedded within a CdS shell5, 6. These structures may have many uses beyond those envisioned for simple quantum dots, which are frequently employed in luminescent applications7. This paper is concerned with changes in the optoelectronic properties of tetrapods when the arms are bent. We demonstrate that seeded tetrapods can serve as an optical strain gauge, capable of measuring forces on the order of nanonewtons. We anticipate that a nanocrystal strain gauge with optical readout will be useful for applications ranging from sensitive optomechanical devices to biological force investigations.
Date: May 26, 2009
Creator: Choi, Charina L; Koski, Kristie J; Sivasankar, Sanjeevi & Alivisatos, A. Paul
Object Type: Article
System: The UNT Digital Library
Automatic Thread-Level Parallelization in the Chombo AMR Library (open access)

Automatic Thread-Level Parallelization in the Chombo AMR Library

The increasing on-chip parallelism has some substantial implications for HPC applications. Currently, hybrid programming models (typically MPI+OpenMP) are employed for mapping software to the hardware in order to leverage the hardware?s architectural features. In this paper, we present an approach that automatically introduces thread level parallelism into Chombo, a parallel adaptive mesh refinement framework for finite difference type PDE solvers. In Chombo, core algorithms are specified in the ChomboFortran, a macro language extension to F77 that is part of the Chombo framework. This domain-specific language forms an already used target language for an automatic migration of the large number of existing algorithms into a hybrid MPI+OpenMP implementation. It also provides access to the auto-tuning methodology that enables tuning certain aspects of an algorithm to hardware characteristics. Performance measurements are presented for a few of the most relevant kernels with respect to a specific application benchmark using this technique as well as benchmark results for the entire application. The kernel benchmarks show that, using auto-tuning, up to a factor of 11 in performance was gained with 4 threads with respect to the serial reference implementation.
Date: May 26, 2011
Creator: Christen, Matthias; Keen, Noel; Ligocki, Terry; Oliker, Leonid; Shalf, John; Van Straalen, Brian et al.
Object Type: Report
System: The UNT Digital Library
Irradiation performance of coextruded enriched uranium fuel rod PT-IP-A172-A: Final report (open access)

Irradiation performance of coextruded enriched uranium fuel rod PT-IP-A172-A: Final report

The proposed operating conditions for fuel elements to be charged into the NPR require the fuel to be of an extended surface geometry and maintain adequate strength and corrosion resistance in 300 C water. A contract was let to Nuclear Metals Inc. to produce by co-extrusion lengths of fuel rod containing both natural and 1.6% enriched uranium of irradiation quality for fabrication into fuel elements. The fuel rods used in the irradiation test represent the first enriched uranium rods coextruded in 0.030 inches of Zircaloy-2 to be irradiated and examined at Hanford. The rods used for this test were fabricated into four, 4 rod cluster fuel elements thus allowing adequate space between individual rods for expansion in the case of a fuel rod failure. This rod was of particular interest since it contained an irregular uranium-Zircaloy-2 interface. The purpose of the irradiation was to determine the dimensional stability of coextruded fuel rods and to determine whether the irregularity in the bond interface had any effect upon the irradiation performance of the fuel. Fuel elements were irradiated in 200 C water in the KER Loop 2 facility to an exposure of 0.28 a/o burnup (2,200 MWD/T). Post irradiation examination showed that …
Date: May 26, 1959
Creator: Claudson, T. T.
Object Type: Report
System: The UNT Digital Library
PWR Blowdown Heat Transfer Separate-Effects Program. Thermal-Hydraulic Test Facility experimental data report for test 167R (open access)

PWR Blowdown Heat Transfer Separate-Effects Program. Thermal-Hydraulic Test Facility experimental data report for test 167R

Reduced instrument responses are presented for Thermal-Hydraulic Test Facility (THTF) test 167R, which is part of the ORNL Pressurized-Water Reactor (PWR) Blowdown Heat Transfer Separate-Effects Program. The objective of the program is to investigate the thermal-hydraulic phenomenon governing the energy transfer and transport processes that occur during a loss-of-coolant accident in a PWR system. Test 167R was conducted to obtain thermal-hydraulic and CHF information in THTF bundle 1 with an intact cold leg. The primary purpose of this report is to make the reduced instrument responses during test 167R available. These are presented in graphical form in engineering units and have been analyzed only to the extent necessary to ensure reasonableness and consistency.
Date: May 26, 1978
Creator: Clemons, V. D.; Hedrick, R. A. & White, M. D.
Object Type: Report
System: The UNT Digital Library
Potential Future Igneous Activity at Yucca Mountain, Nevada (open access)

Potential Future Igneous Activity at Yucca Mountain, Nevada

Location, timing, and volumes of post-Miocene volcanic activity, along with expert judgment, provide the basis for assessing the probability of future volcanism intersecting a proposed repository for nuclear waste at Yucca Mountain, Nevada. Analog studies of eruptive centers in the region that may represent the style and extent of possible future igneous activity at Yucca Mountain have aided in defining the consequence scenarios for intrusion into and eruption through a proposed repository. Modeling of magmatic processes related to magma/proposed repository interactions has been used to assess the potential consequences of a future igneous event through a proposed repository at Yucca Mountain. Results of work to date indicate future igneous activity in the Yucca Mountain region has a very low probability of intersecting the proposed repository. Probability of a future event intersecting a proposed repository at Yucca Mountain is approximately 1.7 x 10{sup -8} per year. Since completion of the Probabilistic Volcanic Hazard Assessment (PVHA) in 1996, anomalies representing potential buried volcanic centers have been identified from aeromagnetic surveys. A re-assessment of the hazard is currently underway to evaluate the probability of intersection in light of new information and to estimate the probability of one or more volcanic conduits located in …
Date: May 26, 2005
Creator: Cline, M.; Perry, F.; Valentine, G. & Smistad, E.
Object Type: Report
System: The UNT Digital Library
Topological change of the Fermi surface in ternary iron-pnictides with reduced c/a ratio: A dHvA study of CaFe2P2 (open access)

Topological change of the Fermi surface in ternary iron-pnictides with reduced c/a ratio: A dHvA study of CaFe2P2

We report a de Haas-van Alphen effect study of the Fermi surface of CaFe{sub 2}P{sub 2} using low temperature torque magnetometry up to 45 T. This system is a close structural analogue of the collapsed tetragonal non-magnetic phase of CaFe{sub 2}As{sub 2}. We find the Fermi surface of CaFe{sub 2}P{sub 2} to differ from other related ternary phosphides in that its topology is highly dispersive in the c-axis, being three-dimensional in character and with identical mass enhancement on both electron and hole pockets ({approx} 1.5). The dramatic change in topology of the Fermi surface suggests that in a state with reduced (c/a) ratio, when bonding between pnictogen layers becomes important, the Fermi surface sheets are unlikely to be nested.
Date: May 26, 2010
Creator: Coldea, Amalia I.; Andrew, C. M. J.; U., /Bristol; Analytis, J. G.; /SIMES, Stanford /SLAC /Stanford U., Phys. Dept.; McDonald, R. D. et al.
Object Type: Article
System: The UNT Digital Library
The use of Dicalite diatomaceous earth as a purge material in the 100 Areas. Final report on production test 105-3-MR (open access)

The use of Dicalite diatomaceous earth as a purge material in the 100 Areas. Final report on production test 105-3-MR

None
Date: May 26, 1952
Creator: Conley, W. R.
Object Type: Report
System: The UNT Digital Library
Special Analysis: Revision of Saltstone Vault 4 Disposal Limits (U) (open access)

Special Analysis: Revision of Saltstone Vault 4 Disposal Limits (U)

New disposal limits have been computed for Vault 4 of the Saltstone Disposal Facility based on several revisions to the models in the existing Performance Assessment and the Special Analysis issued in 2002. The most important changes are the use of a more rigorous groundwater flow and transport model, and consideration of radon emanation. Other revisions include refinement of the aquifer mesh to more accurately model the footprint of the vault, a new plutonium chemistry model accounting for the different transport properties of oxidation states III/IV and V/VI, use of variable infiltration rates to simulate degradation of the closure system, explicit calculation of gaseous releases and consideration of the effects of settlement and seismic activity on the vault structure. The disposal limits have been compared with the projected total inventory expected to be disposed in Vault 4. The resulting sum-of-fractions of the 1000-year disposal limits is 0.2, which indicates that the performance objectives and requirements of DOE 435.1 will not be exceeded. This SA has not altered the conceptual model (i.e., migration of radionuclides from the Saltstone waste form and Vault 4 to the environment via the processes of diffusion and advection) of the Saltstone PA (MMES 1992) nor has …
Date: May 26, 2005
Creator: Cook, J
Object Type: Report
System: The UNT Digital Library
Decontamination and Remodeling of a High Level Chemistry Cell (open access)

Decontamination and Remodeling of a High Level Chemistry Cell

None
Date: May 26, 1954
Creator: Coplan, B. V. & Smith, D. J.
Object Type: Report
System: The UNT Digital Library
Bioinspired synthesis of magnetic nanoparticles (open access)

Bioinspired synthesis of magnetic nanoparticles

The synthesis of magnetic nanoparticles has long been an area of active research. Magnetic nanoparticles can be used in a wide variety of applications such as magnetic inks, magnetic memory devices, drug delivery, magnetic resonance imaging (MRI) contrast agents, and pathogen detection in foods. In applications such as MRI, particle uniformity is particularly crucial, as is the magnetic response of the particles. Uniform magnetic particles with good magnetic properties are therefore required. One particularly effective technique for synthesizing nanoparticles involves biomineralization, which is a naturally occurring process that can produce highly complex nanostructures. Also, the technique involves mild conditions (ambient temperature and close to neutral pH) that make this approach suitable for a wide variety of materials. The term 'bioinspired' is important because biomineralization research is inspired by the naturally occurring process, which occurs in certain microorganisms called 'magnetotactic bacteria'. Magnetotactic bacteria use biomineralization proteins to produce magnetite crystals having very good uniformity in size and morphology. The bacteria use these magnetic particles to navigate according to external magnetic fields. Because these bacteria synthesize high quality crystals, research has focused on imitating aspects of this biomineralization in vitro. In particular, a biomineralization iron-binding protein found in a certain species of …
Date: May 26, 2009
Creator: David, Anand
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Chemistry of coal-related microparticles (open access)

Chemistry of coal-related microparticles

This research project involves the study of coal macerals and sorbent microparticles used to remove S0{sub 2} and/or H{sub 2}S from process streams. To measure reaction rates a charged single microparticle will be held electrodynamically in one or more laser beams by superposed ac and dc electrical fields. The use of the electrodynamic balance for microparticle studies was pioneered by one of the principal investigators. One of the laser beams is used for light-scattering measurements to determine the particle size and to provide the excitation source for obtaining Raman spectra to chemically characterize the particle. The other beam, an infrared beam, is used to heat the particle electromagnetically. The first year of the research was devoted to preliminary experimental work and design studies. Although components and techniques must still be developed, experimental measurements on single macerals are now being done.
Date: May 26, 1992
Creator: Davis, J. E. & Krieger-Brockett, B.
Object Type: Report
System: The UNT Digital Library
Chemistry of coal-related microparticles. Quarterly report, March 1, 1992--May 31, 1992 (open access)

Chemistry of coal-related microparticles. Quarterly report, March 1, 1992--May 31, 1992

This research project involves the study of coal macerals and sorbent microparticles used to remove S0{sub 2} and/or H{sub 2}S from process streams. To measure reaction rates a charged single microparticle will be held electrodynamically in one or more laser beams by superposed ac and dc electrical fields. The use of the electrodynamic balance for microparticle studies was pioneered by one of the principal investigators. One of the laser beams is used for light-scattering measurements to determine the particle size and to provide the excitation source for obtaining Raman spectra to chemically characterize the particle. The other beam, an infrared beam, is used to heat the particle electromagnetically. The first year of the research was devoted to preliminary experimental work and design studies. Although components and techniques must still be developed, experimental measurements on single macerals are now being done.
Date: May 26, 1992
Creator: Davis, J. E. & Krieger-Brockett, B.
Object Type: Report
System: The UNT Digital Library
Higgs Boson Production in Association With Bottom Quarks (open access)

Higgs Boson Production in Association With Bottom Quarks

In the Standard Model, the coupling of the Higgs boson to b quarks is weak, leading to small cross sections for producing a Higgs boson in association with b quarks. However, Higgs bosons with enhanced couplings to b quarks, such as occur in supersymmetric models for large values of tan {beta}, will be copiously produced at both the Tevatron and the LHC in association with b quarks which will be an important discovery channel. We investigate the connections between the production channels, bg {yields} bh and gg {yields} b{bar b}h, at next-to-leading order (NLO) in perturbative QCD and present results for the case with two high-p{sub T} b jets and with one high-p{sub T} b jet at both the Tevatron and the LHC. Finally, the total cross sections without cuts are compared between gg {yields} b{bar b}h at NLO and b{bar b} {yields} h at NNLO.
Date: May 26, 2003
Creator: Dawson, S.; Campbell, J.; Dittmaier, S.; Jackson, C.; Kramer, M. & Maltoni, F.
Object Type: Article
System: The UNT Digital Library
Visualization of Excitonic Structure in the Fenna-Matthews-OlsonPhotosynthetic Complex by Polarization-Dependent Two-DimensionalElectronic Spectroscopy (open access)

Visualization of Excitonic Structure in the Fenna-Matthews-OlsonPhotosynthetic Complex by Polarization-Dependent Two-DimensionalElectronic Spectroscopy

Photosynthetic light-harvesting proceeds by the collection and highly efficient transfer of energy through a network of pigment-protein complexes. Inter-chromophore electronic couplings and interactions between pigments and the surrounding protein determine energy levels of excitonic states and dictate the mechanism of energy flow. The excitonic structure (orientation of excitonic transition dipoles) of pigment-protein complexes is generally deduced indirectly from x-ray crystallography in combination with predictions of transition energies and couplings in the chromophore site basis. Here, we demonstrate that coarse-grained excitonic structural information in the form of projection angles between transition dipole moments can be obtained from polarization-dependent two-dimensional electronic spectroscopy of an isotropic sample, particularly when the nonrephasing or free polarization decay signal rather than the photon echo signal is considered. The method provides an experimental link between atomic and electronic structure and accesses dynamical information with femtosecond time resolution. In an investigation of the Fenna-Matthews-Olson complex from green sulfur bacteria, energy transfer connecting two particular exciton states in the protein is isolated as being the primary contributor to a cross peak in the nonrephasing 2D spectrum at 400 fs under a specific sequence of polarized excitation pulses. The results suggest the possibility of designing experiments using combinations of tailored …
Date: May 26, 2008
Creator: Department of Chemistry, The University of Chicago; Department of Biology, Department of Chemistry, Washington University; Fleming, Graham; Read, Elizabeth L.; Schlau-Cohen, Gabriela S.; Engel, Gregory S. et al.
Object Type: Article
System: The UNT Digital Library
Start-to-End Simulations of the LCLS Accelerator and FEL Performance at Very Low Charge (open access)

Start-to-End Simulations of the LCLS Accelerator and FEL Performance at Very Low Charge

The Linac Coherent Light Source (LCLS) is an x-ray Free-electron Laser (FEL) being commissioned at Stanford Linear Accelerator Center (SLAC). Recent beam measurements have shown that, using the LCLS injector-linac-compressors, the beam emittance is very small at 20 pC. In this paper we perform start-to-end simulations of the entire accelerator including the FEL undulator and study the FEL performance versus the bunch charge. At 20 pC charge, these calculations associated with the measured beam parameters suggest the possibility of generating a longitudinally coherent single x-ray spike with 2-femtosecond (fs) duration at a wavelength of 1.5 nm. At 100 pC charge level, our simulations show an x-ray pulse with 10 femtosecond duration and up to 10{sup 12} photons at a wavelength of 1.5 {angstrom}. These results open exciting possibilities for ultrafast science and single shot molecular imaging.
Date: May 26, 2009
Creator: Ding, Y; Brachmann, A.; Decker, F. J.; Dowell, D.; Emma, P.; Frisch, J. et al.
Object Type: Article
System: The UNT Digital Library
QUALIFICATION OF THE SAVANNAH RIVER SITE 252CF SHUFFLER FOR RECEIPT VERIFICATION MEASUREMENTS OF MIXED U-PU OXIDES STORED IN 9975 SHIPPING CONTAINERS (open access)

QUALIFICATION OF THE SAVANNAH RIVER SITE 252CF SHUFFLER FOR RECEIPT VERIFICATION MEASUREMENTS OF MIXED U-PU OXIDES STORED IN 9975 SHIPPING CONTAINERS

To extend their ability to perform accountability and verification measurements of {sup 235}U in a U-Pu oxide matrix, the K-Area Material Storage facility commissioned the development and construction of a Passive/Active {sup 252}Cf Shuffler. A series of {sup 252}Cf, PuO{sub 2}, and U-Pu oxide standards, in addition to a single U{sub 3}O{sub 8} standard, were measured to characterize and calibrate the shuffler. Accompanying these measurements were simulations using MCNP5/MCNPX, aimed at isolating the neutron countrate contributions for each of the isotopes present. Two calibration methods for determining the {sup 235}U content in mixed UPu oxide were then developed, yielding comparable results. The first determines the {sup 235}U mass by estimating the {sup 239}Pu/{sup 235}U ratio-dependent contributions from the primary delayed neutron contributors. The second defines an average linear response based on the {sup 235}U and {sup 239}Pu mass contents. In each case, it was observed that self-shielding due to {sup 235}U mass has a large influence on the observed rates, requiring bounds on the applicable limits of each calibration method.
Date: May 26, 2011
Creator: Dubose, F.
Object Type: Article
System: The UNT Digital Library
Libby Mitigation Program, 2007 Annual Progress Report: Mitigation for the Construction and Operation of Libby Dam. (open access)

Libby Mitigation Program, 2007 Annual Progress Report: Mitigation for the Construction and Operation of Libby Dam.

Libby Reservoir was created under an International Columbia River Treaty between the United States and Canada for cooperative water development of the Columbia River Basin (Columbia River Treaty 1964). Libby Reservoir inundated 109 stream miles of the mainstem Kootenai River in the United States and Canada, and 40 miles of tributary streams in the U.S. that provided habitat for spawning, juvenile rearing, and migratory passage (Figure 1). The authorized purpose of the dam is to provide power (91.5%), flood control (8.3%), and navigation and other benefits (0.2%; Storm et al. 1982). The Pacific Northwest Power Act of 1980 recognized possible conflicts stemming from hydroelectric projects in the northwest and directed Bonneville Power Administration to 'protect, mitigate, and enhance fish and wildlife to the extent affected by the development and operation of any hydroelectric project of the Columbia River and its tributaries' (4(h)(10)(A)). Under the Act, the Northwest Power Planning Council was created and recommendations for a comprehensive fish and wildlife program were solicited from the region's federal, state, and tribal fish and wildlife agencies. Among Montana's recommendations was the proposal that research be initiated to quantify acceptable seasonal minimum pool elevations to maintain or enhance the existing fisheries (Graham et …
Date: May 26, 2009
Creator: Dunnigan, James; DeShazer, J. & Garrow, L.
Object Type: Report
System: The UNT Digital Library
Project C-018H, 242-A evaporator/PUREX Plant Process Condensate Treatment Facility Instrumentation and Control (I&C) (open access)

Project C-018H, 242-A evaporator/PUREX Plant Process Condensate Treatment Facility Instrumentation and Control (I&C)

This Acceptance Test Procedure (ATP) has been prepared to demonstrate that the Collection System Instrumentation & Control System for Project C-018H performs according to design. Specifically, this ATP is designed to verify the following overall system requirements: The input and outputs properly connected to the LCU terminal strips. The control system software conforms to the configuration specified by the logic diagrams, piping and instrumentation diagrams (P&ID), and the LERF operating philosophy. Testing will be performed using actual signals. If actual signals are not available, then simulated signals will be used to complete the tests.
Date: May 26, 1995
Creator: Dupuis, A.
Object Type: Report
System: The UNT Digital Library
DETECTION OF SUBSURFACE FACILITIES INCLUDING NON-METALLIC PIPE (open access)

DETECTION OF SUBSURFACE FACILITIES INCLUDING NON-METALLIC PIPE

CyTerra has leveraged our unique, shallow buried plastic target detection technology developed under US Army contracts into deeper buried subsurface facilities and including nonmetallic pipe detection. This Final Report describes a portable, low-cost, real-time, and user-friendly subsurface plastic pipe detector (LULU- Low Cost Utility Location Unit) that relates to the goal of maintaining the integrity and reliability of the nation's natural gas transmission and distribution network by preventing third party damage, by detecting potential infringements. Except for frequency band and antenna size, the LULU unit is almost identical to those developed for the US Army. CyTerra designed, fabricated, and tested two frequency stepped GPR systems, spanning the frequencies of importance (200 to 1600 MHz), one low and one high frequency system. Data collection and testing was done at a variety of locations (selected for soil type variations) on both targets of opportunity and selected buried targets. We developed algorithms and signal processing techniques that provide for the automatic detection of the buried utility lines. The real time output produces a sound as the radar passes over the utility line alerting the operator to the presence of a buried object. Our unique, low noise/high performance RF hardware, combined with our field …
Date: May 26, 2003
Creator: Duvoisin, Mr. Herb
Object Type: Report
System: The UNT Digital Library
Anisotropic Shock Propagation in Single Crystals (open access)

Anisotropic Shock Propagation in Single Crystals

Most single-crystal shock experiments have been performed in high-symmetry directions while the nature of shock propagation in low-symmetry directions remains relatively unstudied. It is well known that small-amplitude, linear acoustic waves propagating in low-symmetry directions can focus and/or form caustics (Wolfe, 1995). In this report we provide evidence for similar focusing behavior in nonlinear (shock) waves propagating in single crystals of silicon and diamond. Using intense lasers, we have driven non-planar (divergent geometry) shock waves through single-crystals of silicon or diamond and into an isotropic backing plate. On recovery of the backing plates we observe a depression showing evidence of anisotropic plastic strain with well-defined crystallographic registration. We observe 4-, 2-, and 3-fold symmetric impressions for [100], [110], and [111] oriented crystals respectively.
Date: May 26, 2005
Creator: Eggert, J.; Hicks, D.; Celliers, P.; Bradley, D.; Cox, J.; Unites, W. et al.
Object Type: Article
System: The UNT Digital Library
Save with Solar Newsletter, Vol. 2, Issue 1, Spring 1999 (open access)

Save with Solar Newsletter, Vol. 2, Issue 1, Spring 1999

''Save with Solar'' is a quarterly bulletin produced under the Department of Energy's Federal Energy Management Program for all those who are planning or working on installations of solar and other renewable energy technologies in the Federal government's facilities. Contents include technical information about today's solar technologies and information about the programs, policies, procurement practices, and incentives that support the deployment of renewable energy in the Federal sector. Among the topics covered in this issue is a two-page article about how solar energy is being used by the National Science Foundation in NSF outposts in Antarctica. The newsletter also describes projects that meet the goals of the President's Million Solar Roofs Initiative.
Date: May 26, 1999
Creator: Eiffert, P.
Object Type: Book
System: The UNT Digital Library
An experimental method for investigating phase transformations in the heat affected zone of welds using synchrotron radiation (open access)

An experimental method for investigating phase transformations in the heat affected zone of welds using synchrotron radiation

Although welding is an established technology used in many industrial settings, it is least understand terms of the phases that actually exist, the variation of their spatial disposition with time, and the rate of transformation from one phase to another at various thermal coordinates in the vicinity of the weld. With the availability of high flux and, more recently, high brightness synchrotron x-radiation sources, a number of diffraction and spectroscopic methods have been developed for structural characterization with improved spatial and temporal resolutions to enable in-situ measurements of phases under extreme temperature, pressure and other processing conditions not readily accessible with conventional sources. This paper describes the application of spatially resolved x-ray diffraction (SRXRD) for in-situ investigations of phase transformations in the heat affected zone (HAZ) of fusion welds. Results are presented for gas tungsten (GTA) welds in commercially pure titanium that show the existence of the high temperature bcc {beta}-phase in a 3.3 {plus_minus} 0.3 mm wide HA band adjacent to the liquid weld pool. Phase concentration profiles derived from the SRXRD data further show the co-existence of both the low temperature hcp ({alpha}-phase and the {beta}-phase in the partially, transformed region of the HA. These results represent the …
Date: May 26, 1995
Creator: Elmer, J.W.; Wong, J.; Froba, M.; Waide, P.A. & Larson, E.M.
Object Type: Article
System: The UNT Digital Library