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Technology development for high-salinity geothermal resources (open access)

Technology development for high-salinity geothermal resources

An impulse turbine for Total Flow utilization of geothermal fluids was tested. Performance measurements verify the calculational model. The research goal of 70% engine efficiency remains credible. Addition of acid to the brine prevents scaling and precipitation at moderate costs. Corrosion and erosion of turbine materials for the Total Flow Process are not severe. (JB)
Date: August 5, 1977
Creator: Lundberg, A.W.
System: The UNT Digital Library
Ion beam and defect-related research in the Solid State Division. [LiNbO/sub 3/, Al/sub 2/O/sub 3/] (open access)

Ion beam and defect-related research in the Solid State Division. [LiNbO/sub 3/, Al/sub 2/O/sub 3/]

This paper contains viewgraphs on the topic of radiation effects of solid state materials. In particular, it elaborates on ion beam deposition of thin film structures, ion implantation damage in crystals of Al/sub 2/O/sub 3/, and ion implanted optical waveguides in LiNbO/sub 3/. (LSP)
Date: August 5, 1986
Creator: Roberto, J.B.
System: The UNT Digital Library
CHEMICAL SAFETY: ASKING THE RIGHT QUESTIONS (open access)

CHEMICAL SAFETY: ASKING THE RIGHT QUESTIONS

Recent reports have shown that, despite efforts to the contrary, chemical accidents continue to occur at an unacceptable rate and there is no evidence that this rate is decreasing. Based on this observation, one can conclude that previous analyses have not accurately identified and implemented appropriate fixes to eliminate identified root causes for chemical events. Based on this, it is time to reevaluate chemical accident data with a fresh eye and determine (a) what corrective actions have already been identified but have not been implemented, (b) what other root causes may be involved, and (c) what new corrective actions should be taken to eliminate these newly identified root causes.
Date: August 5, 2008
Creator: Simmons, F
System: The UNT Digital Library
Neutral Kaon Interferometry in Au+Au collisions at sqrt(s_NN) =200 GeV (open access)

Neutral Kaon Interferometry in Au+Au collisions at sqrt(s_NN) =200 GeV

We present the first statistically meaningful results fromtwo-K0s interferometry in heavy-ion collisions. A model that takes theeffect of the strong interaction into account has been used to fit themeasured correlation function. The effects of single and coupled channelwere explored. At the mean transverse mass m_T = 1.07 GeV, we obtain thevalues R = 4.09 +- 0.46 (stat.) +- 0.31 (sys) fm and lambda = 0.92 +-0.23 (stat) +- 0.13 (sys), where R and lambda are the invariant radiusand chaoticity parameters respectively. The results are qualitativelyconsistent with m_T systematics established with pions in a scenariocharacterized by a strong collective flow.
Date: August 5, 2006
Creator: Abelev, B. I.; Adams, J.; Aggarwal, M. M.; Ahammed, Z.; Amonett, J.; Anderson, B. D. et al.
System: The UNT Digital Library
Measurement of B \to X \gamma Decays and Determination of |V_{td}/V_{ts}| (open access)

Measurement of B \to X \gamma Decays and Determination of |V_{td}/V_{ts}|

Using a sample of 383 million B{bar B} events collected by the BABAR experiment, they measure sums of seven exclusive final states B {yields} X{sub d(s)}{gamma}, where X{sub d}(X{sub s}) is a non-strange (strange) charmless hadronic system in the mass range 0.6-1.8 GeV/c{sup 2}. After correcting for unmeasured decay modes in this mass range, they obtain a branching fraction for b {yields} d{gamma} of (7.2 {+-} 2.7(stat.) {+-} 2.3(syst.)) x 10{sup -6}. Taking the ratio of X{sub d} to X{sub s} they find {Lambda}(b {yields} d{gamma})/{Lambda}(b {yields} s{gamma}) = 0.033 {+-} 0.013(stat.) {+-} 0.009(syst.), from which they determine |V{sub td}/V{sub ts}| = 0.177 {+-} 0.043.
Date: August 5, 2008
Creator: Collaboration, The BABAR & Aubert, B.
System: The UNT Digital Library
FULL-SCALE COLD CRUCIBLE TEST ON VITRIFICATION OF SAVANNAH RIVER SITE SB4 HLW SURROGATE (open access)

FULL-SCALE COLD CRUCIBLE TEST ON VITRIFICATION OF SAVANNAH RIVER SITE SB4 HLW SURROGATE

The full-scale cold crucible test on vitrification of sludge batch 4 (SB4) Savannah River Site HLW surrogate using a 418 mm inner diameter stainless steel crucible was carried-out for 66 hrs. Commercially available Frit 503-R4 (8 wt.% Li{sub 2}O, 16 wt.% B{sub 2}O{sub 3}, 76 wt.% SiO{sub 2}) was used as a glass forming additive at a calcine to frit ratio of 1:1 (50 wt.% calcine, 50 wt.% frit). Two portions of slurry prepared from frit and mixture of chemicals simulating waste in amount of {approx}750 kg and from frit and waste surrogate prepared by the SRT-MST-2007-00070 procedure in amount of {approx}1,300 kg with water content of {approx}27 and {approx}50 wt.%, respectively, was processed and {approx}875 kg of the vitrified product in total ({approx}415 + 460 kg) was obtained. Average parameters were as follows: vibration power - 121.6 to 134.1 kW, feed rate (capacity) - 25.1 to 39.8 kg/hr, glass pour rate (productivity) - 14.0 kg/hr specific energy expenses for feed processing - 4.8 to 3.4 kW x hr/kg, specific energy expenses for glass production (melting ratio) - 8.7 to 9.6 kW x hr/kg, specific glass productivity - 2453 kg/(m{sup 2} x d). The product was composed of major vitreous …
Date: August 5, 2008
Creator: Marra, J
System: The UNT Digital Library
CHARACTERIZATION OF VITRIFIED SAVANNAH RIVER SITE SB4 WASTE SURROGATE PRODUCED IN COLD CRUCIBLE (open access)

CHARACTERIZATION OF VITRIFIED SAVANNAH RIVER SITE SB4 WASTE SURROGATE PRODUCED IN COLD CRUCIBLE

Savannah River Site (SRS) sludge batch 4 (SB4) waste surrogate with high aluminum and iron content was vitrified with commercially available Frit 503-R4 (8 wt.% Li{sub 2}O, 16 wt.% B2O3, 76 wt.% SiO{sub 2}) by cold crucible inductive melting using lab- (56 mm inner diameter), bench- (236 mm) and large-scale (418 mm) cold crucible. The waste loading ranged between 40 and 60 wt.%. The vitrified products obtained in the lab-scale cold crucible were nearly amorphous with traces of unreacted quartz in the product with 40 wt.% waste loading and traces of spinel phase in the product with 50 wt.% waste loading. The glassy products obtained in the bench-scale cold crucible are composed of major vitreous and minor iron-rich spinel phase whose content at {approx}60 wt.% waste loading may achieve {approx}10 vol.%. The vitrified waste obtained in the large-scale cold crucible was also composed of major vitreous and minor spinel structure phases. No nepheline phase has been found. Average degree of crystallinity was estimated to be {approx}12 vol.%. Anionic motif of the glass network is built from rather short metasilicate chains and boron-oxygen constituent based on boron-oxygen triangular units.
Date: August 5, 2008
Creator: Marra, J
System: The UNT Digital Library
What Is the Largest Einstein Radius in the Universe? (open access)

What Is the Largest Einstein Radius in the Universe?

The Einstein radius plays a central role in lens studies as it characterizes the strength of gravitational lensing. In particular, the distribution of Einstein radii near the upper cutoff should probe the probability distribution of the largest mass concentrations in the universe. Adopting a triaxial halo model, we compute expected distributions of large Einstein radii. To assess the cosmic variance, we generate a number of Monte-Carlo realizations of all-sky catalogues of massive clusters. We find that the expected largest Einstein radius in the universe is sensitive to parameters characterizing the cosmological model, especially {sigma}{sub s}: for a source redshift of unity, they are 42{sub -7}{sup +9}, 35{sub -6}{sup +8}, and 54{sub -7}{sup +12} arcseconds (errors denote 1{sigma} cosmic variance), assuming best-fit cosmological parameters of the Wilkinson Microwave Anisotropy Probe five-year (WMAP5), three-year (WMAP3) and one-year (WMAP1) data, respectively. These values are broadly consistent with current observations given their incompleteness. The mass of the largest lens cluster can be as small as {approx} 10{sup 15} M{sub {circle_dot}}. For the same source redshift, we expect in all-sky {approx} 35 (WMAP5), {approx} 15 (WMAP3), and {approx} 150 (WMAP1) clusters that have Einstein radii larger than 2000. For a larger source redshift of 7, …
Date: August 5, 2008
Creator: Oguri, Masamune & Blandford, Roger D.
System: The UNT Digital Library
First measurement of the left-right cross section asymmetry in Z boson production at E{sub cm} = 91.5 GeV (open access)

First measurement of the left-right cross section asymmetry in Z boson production at E{sub cm} = 91.5 GeV

The left-right cross section asymmetry for Z boson production in e{sup +} e{sup {minus}} annihilation (A{sub LR}) is being measured at E{sub cm} 91.5 GeV with the SLD detector at the SLAC Linear Collider (SLC) using a longitudinally polarized electron beam. The electron polarization is continually monitored with a Compton scattering polarimeter, and is typically 22%. At the current time, we have accumulated a sample of 4779 Z events. We find that A{sub LR} = 0.02 {double_bond} 0.07 {doteq} 0.001 where the first error is statistical and the second is systematic. Using this very preliminary measurement, we determine the weak mixing angle defined at the Z boson pole to be sin{sup 2}{sub W}{sup olept} = 0.247 {plus_minus} 0.009.
Date: August 5, 1992
Creator: Collaboration, SLD
System: The UNT Digital Library
Overview of crash and impact analysis at Lawrence Livermore National Laboratory (open access)

Overview of crash and impact analysis at Lawrence Livermore National Laboratory

This work provides a brief overview of past and ongoing efforts at Lawrence Livermore National Laboratory (LLNL) in the area of finite-element modeling of crash and impact problems. The process has been one of evolution in several respects. One aspect of the evolution has been the continual upgrading and refinement of the DYNA, NIKE, and TOPAZ family of finite-element codes. The major missions of these codes involve problems where the dominant factors are high-rate dynamics, quasi-statics, and heat transfer, respectively. However, analysis of a total event, whether it be a shipping container drop or an automobile/barrier collision, may require use or coupling or two or more of these codes. Along with refinements in speed, contact capability, and element technology, material model complexity continues to evolve as more detail is demanded from the analyses. A more recent evolution has involved the mix of problems addressed at LLNL and the direction of the technology thrusts. A pronounced increase in collaborative efforts with the civilian and private sector has resulted in a mix of complex problems involving synergism between weapons applications (shipping container, earth penetrator, missile carrier, ship hull damage) and a more broad base of problems such as vehicle impacts as discussed …
Date: August 5, 1993
Creator: Logan, R. W. & Tokarz, F. J.
System: The UNT Digital Library
Through Weld Inspection of Wrought Stainless Steel Piping Using Phased-Array Ultrasonic Probes. (open access)

Through Weld Inspection of Wrought Stainless Steel Piping Using Phased-Array Ultrasonic Probes.

A study was conducted to assess the ability of phased-array ultrasonic techniques to detect and accurately determine the size of flaws from the far-side of wrought austenitic piping welds. Far-side inspections of these welds are currently performed on a “best effort” basis and do not conform to ASME Code Section XI Appendix VIII performance demonstration requirements. For this study, four circumferential welds in 610mm diameter, 36mm thick ASTM A-358, Grade 304 vintage austenitic stainless steel pipe were examined. The welds were fabricated with varied welding parameters; both horizontal and vertical pipe orientations were used, with air and water backing, to simulate field welding conditions. A series of saw cuts, electro-discharge machined (EDM) notches, and implanted fatigue cracks were placed into the heat affected zones of the welds. The saw cuts and notches range in depth from 7.5% to 28.4% through-wall. The implanted cracks ranged in depth from 5% through wall to 64% through wall. The welds were examined with two phased-array probes, a 2.0 MHz transmit-receive longitudinal wave array and a 2.0 MHz transmit-receive shear wave array. These examinations showed that both phased-array transducers were able to detect and accurately length-size, but not depth size, all of the notches and …
Date: August 5, 2004
Creator: Anderson, Michael T.; Cumblidge, Stephen E. & Doctor, Steven R.
System: The UNT Digital Library
Coefficient of Thermal Expansion of the Beta and Delta Polymorphs of HMX (open access)

Coefficient of Thermal Expansion of the Beta and Delta Polymorphs of HMX

Dimensional changes related to temperature cycling of the beta and delta polymorphs of HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) are important for a variety of applications. The coefficient of thermal expansion (CTE) of the beta and delta phases are measured and reported in this work over a temperature range of -20 C to 215 C. In addition, dimensional changes associated with the phase transition were measured, both through the transition and back down. Initially, differential scanning calorimetry (DSC) was used to investigate back conversion of the delta phase to the beta phase polymorph. The most successful approach was first to measure the amount of the beta to delta conversion, then after a given cooling period a repeat analysis, to measure the heat consumed by a second pass through the beta to delta phase transition. In addition, TMA is used to measure the dimensional change of a 0.20-gram sample of HMX during its initial heating and then three days later during a 2nd heating. This HMX shows the beta to delta phase transition a second time, thereby confirming the back conversion from delta to beta phase HMX.
Date: August 5, 2004
Creator: Weese, R K; Burnham, A K & Maienschein, J L
System: The UNT Digital Library
2011 Archaea: Ecology, Metabolism, & Molecular Biology (open access)

2011 Archaea: Ecology, Metabolism, & Molecular Biology

Archaea, one of three major evolutionary lineages of life, are a fascinating and diverse group of microbes with deep roots overlapping those of eukaryotes. The focus of the 'Archaea: Ecology Metabolism & Molecular Biology' GRC conference expands on a number of emerging topics highlighting new paradigms in archaeal metabolism, genome function and systems biology; information processing; evolution and the tree of life; the ecology and diversity of archaea and their viruses. The strength of this conference lies in its ability to couple a field with a rich history in high quality research with new scientific findings in an atmosphere of stimulating exchange. This conference remains an excellent opportunity for younger scientists to interact with world experts in this field.
Date: August 5, 2011
Creator: Stedman, Keneth
System: The UNT Digital Library
Interpretation of rapidly rotating pulsars (open access)

Interpretation of rapidly rotating pulsars

The minimum possible rotational period of pulsars, which are interpreted as rotating neutron stars, is determined by applying a representative collection of realistic nuclear equations of state. It is found that none of the selected equations of state allows for neutron star rotation at periods below 0.8--0.9 ms. Thus, this work strongly supports the suggestion that if pulsars with shorter rotational periods were found, these are likely to be strange-quark-matter stars. The conclusion that the confined hadronic phase of nucleons and nuclei is only metastable would then be almost inescapable, and the plausible ground-state in that event is the deconfined phase of (3-flavor) strange-quark-matter.
Date: August 5, 1992
Creator: Weber, F. (Technische Univ. Muenchen, Garching (Germany). Inst. fuer Theoretische Physik) & Glendenning, N. K. (Lawrence Berkeley Lab., CA (United States))
System: The UNT Digital Library
Thickness and Stack Height Measurement Uncertainty of Experimental Packages for National Ignition Facility Targets (open access)

Thickness and Stack Height Measurement Uncertainty of Experimental Packages for National Ignition Facility Targets

None
Date: August 5, 2011
Creator: Seugling, R. M.; Nederbragt, W. W.; Wilson, M. J.; Blobaum, K. J.; McClure, M. D.; Bennett, D. W. et al.
System: The UNT Digital Library
Quality Assurance Program Description---DWPF (open access)

Quality Assurance Program Description---DWPF

This document describes the Westinghouse Savannah River Company's (WSRC) Quality Assurance Program for Defense Waste Processing at the Savannah River Site (SRS). It identifies and describes the planned activities that constitute the required Quality Assurance Program. The work to which the Quality Assurance Program applies includes both the qualification and production of high-level waste forms. The end result of the program is to provide confidence that these high-level waste forms may be safely and acceptably used to dispose of the radioactive waste that results from activities at SRS in support of national defense.
Date: August 5, 1992
Creator: Maslar, S. R.
System: The UNT Digital Library
2011 Quantum Control of Light & Matter Gordon Research Conference (July 31-August 5, 2011, Mount Holyoke College, South Hadley, MA) (open access)

2011 Quantum Control of Light & Matter Gordon Research Conference (July 31-August 5, 2011, Mount Holyoke College, South Hadley, MA)

Quantum control of light and matter is the quest to steer a physical process to a desirable outcome, employing constructive and destructive interference. Three basic questions address feasibility of quantum control: (1) The problem of controllability, does a control field exist for a preset initial and target state; (2) Synthesis, constructively finding the field that leads to the target; and (3) Optimal Control Theory - optimizing the field that carries out this task. These continue to be the fundamental theoretical questions to be addressed in the conference. How to realize control fields in the laboratory is an ongoing challenge. This task is very diverse viewing the emergence of control scenarios ranging from attoseconds to microseconds. How do the experimental observations reflect on the theoretical framework? The typical arena of quantum control is an open environment where much of the control is indirect. How are control scenarios realized in dissipative open systems? Can new control opportunities emerge? Can one null decoherence effects? An ideal setting for control is ultracold matter. The initial and final state can be defined more precisely. Coherent control unifies many fields of physical science. A lesson learned in one field can reflect on another. Currently quantum information …
Date: August 5, 2011
Creator: Weinacht, Thomas
System: The UNT Digital Library
Imaging of surface structure with energy-dependent photoelectron diffraction (open access)

Imaging of surface structure with energy-dependent photoelectron diffraction

Energy-dependent photoelectron diffraction (EDPD) has been used to determine the surface structure of a surface alloy. Direct imaging has been achieved by Fourier transformation of experimental energy-dependent photoelectron diffraction data. This holographic method, based upon the intersection of contour arcs associated with each measurement direction, can provide vectorial atomic positions with atomic resolution. Experimental analysis is supported by Fourier transformation of simulations from multiple scattering calculations. The surface geometry of c(2x2) Au/Cu(001) has been imaged in an elementally-specific manner, with clear, non-model-dependent discrimination of the surface alloy over the overlayer structure.
Date: August 5, 1993
Creator: Tobin, J. G.; Waddill, G. D.; Li, Hua & Tong, S. Y.
System: The UNT Digital Library
Accretion onto the first stellar mass black holes (open access)

Accretion onto the first stellar mass black holes

The first stars, forming at redshifts z > 15 in minihalos with M {approx} 10{sup 5-6} M{sub {circle_dot}} may leave behind remnant black holes, which could conceivably have been the 'seeds' for the supermassive black holes observed at z {approx}< 7. We study remnant black hole growth through accretion, including for the first time the radiation emitted due to accretion, with adaptive mesh refinement cosmological radiation-hydrodynamical simulations. The effects of photo-ionization and heating dramatically affect the large-scale inflow, resulting in negligible mass growth. We compare cases with accretion luminosity included and neglected to show that accretion radiation drastically changes the environment within 100 pc of the black hole, increasing gas temperatures by an order of magnitude. Gas densities are reduced and further star formation in the same minihalo is prevented for the two hundred million years we followed. Without radiative feedback included most seed black holes do not gain mass as efficiently as has been hoped for in previous theories, implying that black hole remnants of Pop III stars in minihalos are not likely to be miniquasars. Most importantly, however, our calculations demonstrate that if these black holes are indeed accreting close to the Bondi-Hoyle rate with ten percent radiative …
Date: August 5, 2009
Creator: Alvarez, Marcelo A.; Wise, John H. & Abel, Tom
System: The UNT Digital Library
Stretch-Parameterized Light Curves for High Redshift SN Ia Studies (open access)

Stretch-Parameterized Light Curves for High Redshift SN Ia Studies

None
Date: August 5, 1997
Creator: Kim, Alex G
System: The UNT Digital Library
Analysis and Modeling of Laser Ramps and Shocks in Tiitatium and Zirconium With Phase Transitions (open access)

Analysis and Modeling of Laser Ramps and Shocks in Tiitatium and Zirconium With Phase Transitions

None
Date: August 5, 2011
Creator: Heuze, O. & Swift, D. C.
System: The UNT Digital Library
LASER ENGINEERED NET SHAPING FOR REPAIR AND HYDROGEN COMPATIBILITY (open access)

LASER ENGINEERED NET SHAPING FOR REPAIR AND HYDROGEN COMPATIBILITY

A method to repair mismatched or damaged components using Laser Engineered Net Shaping{sup R} (LENS) technology to apply material was investigated for its feasibility for components exposed to hydrogen. The mechanical properties of LENS bulk materials were also tested for hydrogen compatibility. The LENS process was used to repair simulated and actual mismachined components. These sample components were hydrogen charged and burst tested in the as-received, as-damaged, and as-repaired conditions. The testing showed that there was no apparent additional deficiency associated with hydrogen charging compared to the repair technique. The repair techniques resulted in some components meeting the requirements while others did not. Additional procedure/process development is required prior to recommending production use of LENS.
Date: August 5, 2011
Creator: Korinko, P. & Adams, T.
System: The UNT Digital Library
Parametrically Adaptive Wavenumber Processing for Mode Tracking in a Shallow Ocean Environment (open access)

Parametrically Adaptive Wavenumber Processing for Mode Tracking in a Shallow Ocean Environment

None
Date: August 5, 2013
Creator: Candy, J V
System: The UNT Digital Library
System Dynamics and Control System for a High Bandwidth Rotary Actuator and Fast Tool Servo (open access)

System Dynamics and Control System for a High Bandwidth Rotary Actuator and Fast Tool Servo

This paper explores some of the system dynamics and control issues for a short-stroke rotary actuator that we designed and tested for a new fast tool servo referred to as the 10 kHz rotary fast tool servo. The use of a fast tool servo (FTS) with a diamond turning machine for producing non-axisymmetric or textured surfaces on a workpiece is well known. In a previous paper [1] the authors provide details on the mechanical design and trade-off issues that were considered during the design phase for the fast tool servo. At the heart of that machine is the normal-stress variable reluctance rotary actuator described in more detail in this paper. In addition to producing the torque that is needed for the 10 kHz rotary fast tool servo, the actuator produces a force and is therefore referred to as a hybrid rotary/linear actuator. The actuator uses bias and steering magnetic fluxes for linearizing the torque versus current relationship. Certain types of electric engraving heads use an actuator similar in principle to our hybrid actuator. In the case of the engraving heads, the actuator is used to produce and sustain a resonating mechanical oscillator. This is in sharp contrast to the arbitrary …
Date: August 5, 2005
Creator: Montesanti, R C & Trumper, D L
System: The UNT Digital Library