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INCONEL 690 CORROSION IN WTP (WASTE TREATMENT PLANT) HLW (HIGH LEVEL WASTE) GLASS MELTS RICH IN ALUMINUM & BISMUTH & CHROMIUM OR ALUMINUM/SODIUM
Metal corrosion tests were conducted with four high waste loading non-Fe-limited HLW glass compositions. The results at 1150 C (the WTP nominal melter operating temperature) show corrosion performance for all four glasses that is comparable to that of other typical borosilicate waste glasses, including HLW glass compositions that have been developed for iron-limited WTP streams. Of the four glasses tested, the Bi-limited composition shows the greatest extent of corrosion, which may be related to its higher phosphorus content. Tests at higher suggest that a moderate elevation of the melter operating temperature (up to 1200 C) should not result in any significant increase in Inconel corrosion. However, corrosion rates did increase significantly at yet higher temperatures (1230 C). Very little difference was observed with and without the presence of an electric current density of 6 A/inch{sup 2}, which is the typical upper design limit for Inconel electrodes. The data show a roughly linear relationship between the thickness of the oxide scale on the coupon and the Cr-depletion depth, which is consistent with the chromium depletion providing the material source for scale growth. Analysis of the time dependence of the Cr depletion profiles measured at 1200 C suggests that diffusion of Cr …
Date:
November 5, 2009
Creator:
AA, KRUGER; Z, FENG; H, GAN & IL, PEGG
Object Type:
Report
System:
The UNT Digital Library
Micromilling of Metal Alloys with Focused Ion Beam-Fabricated Tools
This work combines focused ion beam sputtering and ultra-precision machining as a first step in fabricating microstructure in metals and alloys. Specifically, {approx}25{micro}m diameter micro-end mills are made from cobalt M42 high-speed steel and C2 micrograin tungsten carbide tool blanks by ion beam sputtering. A 20 keV focused gallium beam defines tool cutting edges having radii of curvature < 0.1{micro}m. Micro-end mills having 2, 4 and 5 cutting edges successfully machine small trenches in 6061-T4 aluminum, brass, 4340 steel and polymethyl methacrylate. Machined trench widths are approximately equal to the tool diameters and surface roughnesses (rms) are {approx}150 nm or less. Microtools are robust and operate for more than 6 hours without fracture. Results from ultra-precision machining aluminum at feed rates as high as 50 mm/minute are included.
Date:
November 5, 1999
Creator:
ADAMS,DAVID P.; VASILE,M.J.; BENAVIDES,GILBERT L. & CAMPBELL,ANN N.
Object Type:
Article
System:
The UNT Digital Library
Ion Beam Sputter Fabrication of Micro-Grooving and Micro-Threading Tools
This paper presents techniques for fabricating microscopic, nonplanar features in a variety of materials. Micro-grooving and micro-threading tools having cutting dimensions of 10-30{micro}m are made by focused ion beam sputtering and used in ultra-precision machining. Tool fabrication involves directing a 20 keV gallium beam at polished cylindrical punches made of cobalt M42 high-speed steel or C2 tungsten carbide. This creates cutting edges having radii of curvature less than 0.4 {micro}m, and rake features similar to conventional lathe tools. Clearance for minimizing frictional drag of a tool results from the sputter yield dependence on ion herd target incidence angle. Numerically controlled, ultra-precision machining with micro-grooving tools results in a close matching between tool width and feature size. Microtools controllably machine 13 {micro}m wide, 4 {micro}m deep, helical grooves in polymethyl methacrylate and 6061-T6 Al cylindrical substrates. Micro-grooving tools also fabricate sinusoidal waveform features in polished metal substrates.
Date:
November 5, 1999
Creator:
Adams,David P.; Vasile,M. J. & Krishnan,A. S. M.
Object Type:
Article
System:
The UNT Digital Library
Geometric transitions and D-term SUSY breaking
We propose a new way of using geometric transitions to study metastable vacua in string theory and certain confining gauge theories. The gauge theories in question are N=2 supersymmetric theories deformed to N=1 by superpotential terms. We first geometrically engineer supersymmetry-breaking vacua by wrapping D5 branes on rigid 2-cycles in noncompact Calabi-Yau geometries, such that the central charges of the branes are misaligned. In a limit of slightly misaligned charges, this has a gauge theory description, where supersymmetry is broken by Fayet-Iliopoulos D-terms. Geometric transitions relate these configurations to dual Calabi-Yaus with fluxes, where H_RR, H_NS and dJ are all nonvanishing. We argue that the dual geometry can be effectively used to study the resulting non-supersymmetric, confining vacua
Date:
November 5, 2007
Creator:
Aganagic, Mina; Aganagic, Mina & Beem, Christopher
Object Type:
Article
System:
The UNT Digital Library
Rotary Engine
Patent for "a new and improved rotary engine which is simple and durable in construction and very effective in operation, using the steam expansively and to the fullest advantage, at the same time being adapted to compound engines" (lines 8-12).
Date:
November 5, 1889
Creator:
Akers, William P.
Object Type:
Patent
System:
The Portal to Texas History
Gray Wolves Under the Endangered Species Act: Distinct Population Segments and Experimental Populations
This report looks at the distinct population segments (DPSs) process as it is applied to the gray wolf. It also reviews experimental populations of wolves under the Endangered Species Act (ESA) and their protections.
Date:
November 5, 2007
Creator:
Alexander, Kristina & Corn, M. L.
Object Type:
Report
System:
The UNT Digital Library
N-17, A Delayed Neutron Emitter
The decay scheme of a 4.2 second neutron emitter has been investigated in detail. Chemical and physical evidence shows that it is N{sup 17}, which emits beta rays to a broad excited state of O{sup 17}, which then breaks up into a neutron plus O{sup 16}. The energy spectrum of the neutrons is determined by measuring the energies of the O{sup 16} recoils in a proportional counter. The neutrons have a most probable energy of 0.9 Mev, a 'half width' of less than .5 Mev, and an upper limit of about 2 Mev. {beta}-recoil coincidences are observed, as predicted by the Bohr-Wheeler theory, and the {beta}-ray energy is measured by absorption. The beta rays in coincidence with neutrons have an upper limit of 3.7 {+-} 0.2 Mev. Beta-rays directly to the ground stat of O{sup 17} are not observed because of high background effects, but should have an energy of 8.7 Mev. Some evidence is presented to show that energy is conserved in the {beta}-n transition through the broad excited state in O{sup 17}.
Date:
November 5, 1948
Creator:
Alvarez, L. W.
Object Type:
Report
System:
The UNT Digital Library
The human DNA-activated protein kinase, DNA-PK: Substrate specificity
Although much has been learned about the structure and function of p53 and the probable sequence of subsequent events that lead to cell cycle arrest, little is known about how DNA damage is detected and the nature of the signal that is generated by DNA damage. Circumstantial evidence suggests that protein kinases may be involved. In vitro, human DNA-PK phosphorylates a variety of nuclear DNA-binding, regulatory proteins including the tumor suppressor protein p53, the single-stranded DNA binding protein RPA, the heat shock protein hsp90, the large tumor antigen (TAg) of simian virus 40, a variety of transcription factors including Fos, Jun, serum response factor (SRF), Myc, Sp1, Oct-1, TFIID, E2F, the estrogen receptor, and the large subunit of RNA polymerase II (reviewed in Anderson, 1993; Jackson et al., 1993). However, for most of these proteins, the sites that are phosphorylated by DNA-PK are not known. To determine if the sites that were phosphorylated in vitro also were phosphorylated in vivo and if DNA-PK recognized a preferred protein sequence, the authors identified the sites phosphorylated by DNA-PK in several substrates by direct protein sequence analysis. Each phosphorylated serine or threonine is followed immediately by glutamine in the polypeptide chain; at no …
Date:
November 5, 1994
Creator:
Anderson, C.W.; Connelly, M.A.; Zhang, H.; Sipley, J.A.; Lees-Miller, S.P.; Lintott, L.G. et al.
Object Type:
Report
System:
The UNT Digital Library
The European Parliament
The European Parliament (EP) is one of the three key institutions of the European Union (EU), and the only EU institution whose members are directly elected. This report discusses the construction and history of the EP, its role in functions of the EU as well as internationally, various international supports and criticisms of the EP, and the EP's ties with the U.S. Congress.
Date:
November 5, 2010
Creator:
Archick, Kristin & Mix, Derek E.
Object Type:
Report
System:
The UNT Digital Library
The European Union: Questions and Answers
This report provides a brief overview of the European Union (EU), an economic and political partnership between 27 sovereign member states. The report describes the formation of the EU, the three main institutions of the EU, and the EU's relationship with the United States.
Date:
November 5, 2010
Creator:
Archick, Kristin & Mix, Derek E.
Object Type:
Report
System:
The UNT Digital Library
Guinea's 2008 Military Coup and Relations with the United States
This report analyzes developments since the Guinean military's seizure of power in December 2008, Guinea's relations with the United States, and U.S. policy in the wake of the coup. It also provides background on Guinean history and politics.
Date:
November 5, 2009
Creator:
Arieff, Alexis & Cook, Nicolas
Object Type:
Report
System:
The UNT Digital Library
Laser Engineered Net Shaping (LENS(TM)): A Tool for Direct Fabrication of Metal Parts
For many years, Sandia National Laboratories has been involved in the development and application of rapid prototyping and dmect fabrication technologies to build prototype parts and patterns for investment casting. Sandia is currently developing a process called Laser Engineered Net Shaping (LENS~) to fabricate filly dense metal parts dwectly from computer-aided design (CAD) solid models. The process is similar to traditional laser-initiated rapid prototyping technologies such as stereolithography and selective laser sintering in that layer additive techniques are used to fabricate physical parts directly from CAD data. By using the coordinated delivery of metal particles into a focused laser beam apart is generated. The laser beam creates a molten pool of metal on a substrate into which powder is injected. Concurrently, the substrate on which the deposition is occurring is moved under the beam/powder interaction zone to fabricate the desired cross-sectiwal geometry. Consecutive layers are additively deposited, thereby producing a three-dmensional part. This process exhibits enormous potential to revolutionize the way in which metal parts, such as complex prototypes, tooling, and small-lot production parts, are produced. The result is a comple~ filly dense, near-net-shape part. Parts have been fabricated from 316 stainless steel, nickel-based alloys, H13 tool steel, and titanium. …
Date:
November 5, 1998
Creator:
Atwood, C.; Ensz, M.; Greene, D.; Griffith, M.; Harwell, L.; Reckaway, D. et al.
Object Type:
Article
System:
The UNT Digital Library
Trip Report Consultation on Organic Reactor Coolants
There is a continuing high interest in the development of organic coolant technology for application to future Hanford reactors. In addition to the HAPO organic program, two other programs are being sponsored by the Atomic Energy Commission. These include the Naval Reactor program, aimed at a reactor for ship propulsion, and the Civilian Power Reactor program. Because of the similarity of the technical efforts in the three programs, an attempt is being made to establish effective liaison among the programs. To this end, a visit was made to several sites actively engaged in organic development work. These sites and their primary functions are detailed in this report.
Date:
November 5, 1956
Creator:
Atwood, J. M.; Cook, M. W. & Eddy, P. P
Object Type:
Report
System:
The UNT Digital Library
Search for Invisible Decays of a Light Scalar in Radiative Transitions Y(3S)->gamma A0
We search for a light scalar particle produced in single-photon decays of the {Upsilon}(3S) resonance through the process {Upsilon}(3S) {yields} {gamma} + A{sup 0}, A{sup 0} {yields} invisible. Such an object appears in Next-to-Minimal Supersymmetric extensions of the Standard Model, where a light CP-odd Higgs boson naturally couples strongly to b-quarks. If, in addition, there exists a light, stable neutralino, decays of A{sup 0} could be preferentially to an invisible final state. We search for events with a single high-energy photon and a large missing mass, consistent with a 2-body decay of {Upsilon}(3S). We find no evidence for such processes in a sample of 122 x 10{sup 6} {Upsilon}(3S) decays collected by the BABAR collaboration at the PEP-II B-factory, and set 90% C.L. upper limits on the branching fraction {Beta}({Upsilon}(3S) {yields} {gamma}A{sup 0}) x {Beta}(A{sup 0} {yields} invisible) at (0.7-31) x 10{sup -6} in the mass range m{sub A{sup 0}} {le} 7.8 GeV. The results are preliminary.
Date:
November 5, 2008
Creator:
Aubert, B.
Object Type:
Article
System:
The UNT Digital Library
Evidence for B Semileptonic Decays into the Lambda_c Charm Baryon
We present the first evidence for B semileptonic decays into the charmed baryon {Lambda}{sub c}{sup +} based on 420 fb{sup -1} of data collected at the {Upsilon}(4S) resonance with the BABAR detector at the PEP-II e{sup +}e{sup -} storage rings. Events are tagged by fully reconstructing one of the B mesons in a hadronic decay mode. We measure the relative branching fraction {Beta}({bar B} {yields} {Lambda}{sub c}{sup +} X{ell}{sup -}{bar {nu}}{sub {ell}})/{Beta}({bar B} {yields} {Lambda}{sub c}{sup +}/{bar {Lambda}}{sub c}{sup -}X) = (3.2 {+-} 0.9{sub stat.} {+-} 0.9{sub syst.})%. The significance of the signal including the systematic uncertainty is 4.9 standard deviations.
Date:
November 5, 2008
Creator:
Aubert, Bernard; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
Object Type:
Article
System:
The UNT Digital Library
Measurement of the Branching Fractions of Bbar -> D** l^- nubar_l Decays in Events Tagged by a Fully Reconstructed B Meson
We report a measurement of the branching fractions of {bar B} {yields} D** {ell}{sup -}{bar {nu}}{sub {ell}} decays based on 417 fb{sup -1} of data collected at the {Upsilon}(4S) resonance with the BABAR detector at the PEP-II e{sup +}e{sup -} storage rings. Events are selected by fully reconstructing one of the B mesons in a hadronic decay mode. A fit to the invariant mass differences m(D{sup (*)})-m(D{sup (*)}) is performed to extract the signal yields of the different D** states. We observe the {bar B} {yields} D**{ell}{sup -}{bar {nu}}{sub {ell}} decay modes corresponding to the four D** states predicted by Heavy Quark Symmetry with a significance greater than six standard deviations including systematic uncertainties.
Date:
November 5, 2008
Creator:
Aubert, Bernard; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
Object Type:
Article
System:
The UNT Digital Library
ACCOMPLISHMENTS OF THE AMERICAN-POLISH PROGRAM FOR ELIMINATION OF LOW EMISSIONS IN KRAKOW
In 1991, US and Polish officials signed a Memorandum of Understanding formally initiating and directing the Cracow Clean Fossil Fuels and Energy Efficiency Program. Developing a program approach for the most effective use of the available funds required considerable effort on the part of all project participants. The team recognized early that the cost of solving the low emissions problem even in only one city far exceeded the amount of available US funds. Economic conditions in Poland limited availability of local capital funds for environmental projects. Imposing environmental costs on struggling companies or city residents under difficult conditions of the early 1990's required careful consideration of the economic and political impacts. For all of these reasons the program sought to identify technologies for achieving air quality goals which, through improved efficiency and/or reduced fuel cost, could be so attractive economically as to lead to self-sustaining activities beyond the end of the formal project. The effort under this program has been focused into 5 main areas of interest as follows: (1) Energy Conservation and Extension of Central Station District Heating; (2) Replacement of Coal- and Coke-Fired Boilers with Natural Gas-Fired Boilers; (3) Replacement of Coal-Fired Home Stoves with Electric Heating Appliances; …
Date:
November 5, 1998
Creator:
BUTCHER,T.A. & PIERCE,B.
Object Type:
Article
System:
The UNT Digital Library
W-320 waste retrieval sluicing system transfer line flushing volume and frequency calculation
The calculations contained in this analysis document establish the technical basis for the volume, frequency, and flushing fluid to be utilized for routine Waste Retrieval Sluicing System (WRSS) process line flushes. The WRSS was installed by Project W-320, Tank 24 I-C-106 Sluicing. The double contained pipelines being flushed have 4 inch stainless steel primary pipes. The flushes are intended to prevent hydrogen build up in the transfer lines and to provide ALARA conditions for maintenance personnel.
Date:
November 5, 1997
Creator:
Bailey, J. W.
Object Type:
Report
System:
The UNT Digital Library
Asymptotic Diffusion-Limit Accuracy of Sn Angular Differencing Schemes
In a previous paper, Morel and Montry used a Galerkin-based diffusion analysis to define a particular weighted diamond angular discretization for S{sub n}n calculations in curvilinear geometries. The weighting factors were chosen to ensure that the Galerkin diffusion approximation was preserved, which eliminated the discrete-ordinates flux dip. It was also shown that the step and diamond angular differencing schemes, which both suffer from the flux dip, do not preserve the diffusion approximation in the Galerkin sense. In this paper we re-derive the Morel and Montry weighted diamond scheme using a formal asymptotic diffusion-limit analysis. The asymptotic analysis yields more information than the Galerkin analysis and demonstrates that the step and diamond schemes do in fact formally preserve the diffusion limit to leading order, while the Morel and Montry weighted diamond scheme preserves it to first order, which is required for full consistency in this limit. Nonetheless, the fact that the step and diamond differencing schemes preserve the diffusion limit to leading order suggests that the flux dip should disappear as the diffusion limit is approached for these schemes. Computational results are presented that confirm this conjecture. We further conjecture that preserving the Galerkin diffusion approximation is equivalent to preserving the …
Date:
November 5, 2009
Creator:
Bailey, T S; Morel, J E & Chang, J H
Object Type:
Article
System:
The UNT Digital Library
Determination of Dark Matter Properties at High-Energy Colliders
If the cosmic dark matter consists of weakly-interacting massive particles, these particles should be produced in reactions at the nextgeneration of high-energy accelerators. Measurements at these accelerators can then be used to determine the microscopic properties of the dark matter. From this, we can predict the cosmic density, the annihilation cross sections, and the cross sections relevant to direct detection. In this paper, we present studies in supersymmetry models with neutralino dark matter that give quantitative estimates of the accuracy that can be expected. We show that these are well matched to the requirements of anticipated astrophysical observations of dark matter. The capabilities of the proposed International Linear Collider (ILC) are expected to play a particularly important role in this study.
Date:
November 5, 2006
Creator:
Baltz, Edward A.; Battaglia, Marco; Peskin, Michael E. & Wizansky, Tommer
Object Type:
Article
System:
The UNT Digital Library
Single top production and top properties at the Tevatron
We summarize recent measurements made at the Tevatron Collider using top event candidates. Cross section and mass measurements are discussed in a separate contribution to these Proceedings. Here we report on studies of the top P<sub>T</sub> distribution in t{anti t} production and studies of single top production. Properties of top decays examined are: BF(t {yields} Wb)/BF(t {yields} Wq), helicity amplitudes of W's from top decays and correlations of t{anti t} decay products. Searches for new physics in rare top decays and a search for a state X {yields} t{anti t} are also reported.
Date:
November 5, 1999
Creator:
Barbaro-Galtieri, Angela
Object Type:
Article
System:
The UNT Digital Library
Fast Multipole Solvers for Three-Dimensional Radiation and Fluid Flow Problems
A number of physics problems can be modeled by a set of N elements, which have pair-wise interactions with one another. The use of such elements for the evolution of vorticity in fluid flows and the calculation of the velocity field from the evolving vorticity field is well known. Fast multipole methods for fluid flow problems have been developed in we pmt to reduce computational effort to something less than O(N) . In this paper we develop a fast multipole solver with application to both 3-D radiation problems (calculation of the heat flux from the evolving temperature field in an absorbing medium) and 3-D fluid flow. This is accomplished by using a more general kernel for the associated volume integrals. This kernel also encompasses other applications such as gravitational fields, electrostatics, scattering, etc. The present algorithm has been designed to have a very high "parallel efficiency" when used on massively parallel computers. This feature comes at the expense of computational effort, which is less than O(N) but greater than O(N) or O(MnN).
Date:
November 5, 1998
Creator:
Baty, R. S.; Burns, S. P.; Gritzo, L. A.; Homicz, G. F. & Strickland, J. H.
Object Type:
Article
System:
The UNT Digital Library
Holographic Systematics of D-brane Inflation
We provide a systematic treatment of possible corrections to the inflaton potential for D-brane inflation in the warped deformed conifold. We consider the D3-brane potential in the presence of the most general possible corrections to the throat geometry sourced by coupling to the bulk of a compact Calabi-Yau space. This corresponds to the potential on the Coulomb branch of the dual gauge theory, in the presence of arbitrary perturbations of the Lagrangian. The leading contributions arise from perturbations by the most relevant operators that do not destroy the throat geometry. We find a generic contribution from a non-chiral operator of dimension {Delta} = 2 associated with a global symmetry current, resulting in a negative contribution to the inflaton mass-squared. If the Calabi-Yau preserves certain discrete symmetries, this is the dominant correction to the inflaton potential, and fine-tuning of the inflaton mass is possible. In the absence of such discrete symmetries, the dominant contribution comes from a chiral operator with {Delta} = 3/2, corresponding to a {phi}{sup 3/2} term in the inflaton potential. The resulting inflationary models are phenomenologically identical to the inflection point scenarios arising from specific D7-brane embeddings, but occur under far more general circumstances. Our strategy extends immediately …
Date:
November 5, 2008
Creator:
Baumann, Daniel; /Harvard U., Phys. Dept. /Princeton U.; Dymarsky, Anatoly; /Stanford U., Phys. Dept.; Kachru, Shamit; /Stanford U., Phys. Dept. /SLAC et al.
Object Type:
Article
System:
The UNT Digital Library
Brooder
Patent for a brooder which prevents chicks from entering after a certain number have gone through the door.
Date:
November 5, 1912
Creator:
Becker, August B.
Object Type:
Patent
System:
The Portal to Texas History