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Proceedings of the workshop on the impact of hydrogen on water reactor safety. Volume II of IV (open access)

Proceedings of the workshop on the impact of hydrogen on water reactor safety. Volume II of IV

Separate abstracts were prepared for the papers presented in the subject area: hydrogen sources and detection.
Date: January 26, 1981
Creator: Berman, M. (ed.)
System: The UNT Digital Library
Line-imaging velocimeter for shock diagnostics at the OMEGA laser facility (open access)

Line-imaging velocimeter for shock diagnostics at the OMEGA laser facility

None
Date: January 26, 2004
Creator: Celliers, P M; Bradley, D K; Collins, G W; Hicks, D G; Boehly, T R & Armstrong, W J
System: The UNT Digital Library
Local Structure of La1-xSrxCoO3 determined from EXAFS and neutron PDF studies (open access)

Local Structure of La1-xSrxCoO3 determined from EXAFS and neutron PDF studies

The combined local structure techniques, extended x-ray absorption fine structure (EXAFS) and neutron pair distribution function analysis, have been used for temperatures 4<= T<= 330 K to rule out a large Jahn-Teller (JT) distortion of the Co-O bond in La1?xSrxCoO3 for a significant fraction of Co sites (x<= 0.35), indicating few, if any, JT-active, singly occupied eg Co sites exist.
Date: January 26, 2009
Creator: Sundaram, N.; Jiang, Y.; Anderson, I. E.; Belanger, D. P.; Booth, C. H.; Bridges, F. et al.
System: The UNT Digital Library
Evaluation of an Unsuccessful Brook Trout Electrofishing Removal Project in a Small Rocky Mountain Stream. (open access)

Evaluation of an Unsuccessful Brook Trout Electrofishing Removal Project in a Small Rocky Mountain Stream.

In the western United States, exotic brook trout Salvelinus fontinalis frequently have a deleterious effect on native salmonids, and biologists often attempt to remove brook trout from streams by means of electrofishing. Although the success of such projects typically is low, few studies have assessed the underlying mechanisms of failure, especially in terms of compensatory responses. A multiagency watershed advisory group (WAG) conducted a 3-year removal project to reduce brook trout and enhance native salmonids in 7.8 km of a southwestern Idaho stream. We evaluated the costs and success of their project in suppressing brook trout and looked for brook trout compensatory responses, such as decreased natural mortality, increased growth, increased fecundity at length, and earlier maturation. The total number of brook trout removed was 1,401 in 1998, 1,241 in 1999, and 890 in 2000; removal constituted an estimated 88% of the total number of brook trout in the stream in 1999 and 79% in 2000. Although abundance of age-1 and older brook trout declined slightly during and after the removals, abundance of age-0 brook trout increased 789% in the entire stream 2 years after the removals ceased. Total annual survival rate for age-2 and older brook trout did not …
Date: January 26, 2006
Creator: Meyer, Kevin A.; Lamansky, Jr., James A. & Schill, Daniel J.
System: The UNT Digital Library
Dalitz Plot Analysis of Ds+->pi+pi-pi+ (open access)

Dalitz Plot Analysis of Ds+->pi+pi-pi+

A Dalitz plot analysis of {approx} 13, 000 D{sub s}{sup +} decays to {pi}{sup +}{pi}{sup +}{pi}{sup -} has been performed. A 384 fb{sup -1} data sample, recorded by the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} storage ring running at center of mass energies near 10.6 GeV, is used. Amplitudes and phases of the intermediate resonances which contribute to this final state are measured. A high precision measurement of the ratio: {Beta}(D{sub s}{sup +} {yields} {pi}{sup +}{pi}{sup +}{pi}{sup -})/{Beta}(D{sub s}{sup +} {yields} K{sup +}K{sup -}{pi}{sup +}) = 0.199 {+-} 0.004 {+-} 0.006 is performed. Using a model independent partial wave analysis the amplitude and phase of the S-wave have been measured.
Date: January 26, 2009
Creator: Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
System: The UNT Digital Library
Bonding and Bridging Forms of Social Capital in Wildlife Tourism Microentrepreneurship: An Application of Social Network Analysis (open access)

Bonding and Bridging Forms of Social Capital in Wildlife Tourism Microentrepreneurship: An Application of Social Network Analysis

This article examines a network of wildlife tourism microentrepreneurs for bonding and bridging forms of social capital using a social network analysis approach.
Date: December 29, 2017
Creator: KC, Birendra; Morais, Duarte B.; Seekamp, Erin; Smith, Jordan W. & Peterson, M. Nils
System: The UNT Digital Library
Fusion technology status and requirements (open access)

Fusion technology status and requirements

This paper summarizes the status of fusion technology and discusses the requirements to be met in order to build a demonstration fusion plant. Strategies and programmatic considerations in pursuing engineering feasibility are also outlined.
Date: January 26, 1982
Creator: Thomassen, K.I.
System: The UNT Digital Library
Laser irradiation of disk targets at 0. 53. mu. m wavelength (open access)

Laser irradiation of disk targets at 0. 53. mu. m wavelength

We present results and analysis for laser-irradiations of Be, CH, Ti, and Au disk targets with 0.53 ..mu..m light in 3 to 35 J, 600 ps pulses, at nominal intensities from 3 x 10/sup 13/ to approx. 4 x 10/sup 15/ W/cm/sup 2/. The measured absorptions are higher than observed in similar 1.06 ..mu..m irradiations, and are largely consistent with modeling which shows the importance of inverse bremsstrahlung and Brillouin scattering. Observed red-shifted back-reflected light shows that Brillouin is operating at low to moderate levels. The measured fluxes of multi-keV x-rays indicate low hot-electron fractions, with temperatures which are consistent with resonance absorption. Measurements show efficient conversion of absorbed light into sub-keV x-rays, with time-, angular-, and spatial-emission distributions which are generally consistent with non-LTE modeling using inhibited thermal electron transport.
Date: January 26, 1981
Creator: Mead, W.C.; Campbell, E.M. & Estabrook, K.G.
System: The UNT Digital Library
News from LBL (open access)

News from LBL

We present a brief summary of recent news from LBL related to accelerator physics. This talk was given on October 29, 1993 at the 6th Advanced ICFA Beam Dynamics Workshop on the subject ``Synchro- Betraton Resonances,`` held in Funchal (Madeira, Portugal), October 24--30, 1993.
Date: January 26, 1994
Creator: Furman, M. A.
System: The UNT Digital Library
Effect of multiple and delayed jet impact and penetration on concrete target borehole diameter (open access)

Effect of multiple and delayed jet impact and penetration on concrete target borehole diameter

The effect of multiple and delayed jet impact and penetration on the borehole diameter in concrete targets is discussed in this paper. A first-order principle of shaped-charge jet penetration is that target hole volume is proportional to the energy deposited in the target by the jet. This principle is the basis for the relation that target borehole diameter at any depth along the penetration path is proportional to the jet energy deposited in the target at that location. Our current research shows that the 'jet energy per unit hole volume constant' for concrete can be substantially altered by the use of multiple and delayed jet impacts. It has been shown that enhanced entrance crater formation results from the simultaneous impact and penetration of three shaped-charge jets. We now demonstrate that enhanced borehole diameter is also observed by the simultaneous impact and penetration of multiple shaped-charge jets followed by the delayed impact and penetration of a single shaped-charge jet.
Date: January 26, 2001
Creator: Murphy, M J; Baum, D W; Kuklo, R M & Simonson, S C
System: The UNT Digital Library
LESSONS LEARNED FROM A RECENT LASER ACCIDENT (open access)

LESSONS LEARNED FROM A RECENT LASER ACCIDENT

A graduate student received a laser eye injury from a femtosecond Ti:sapphire laser beam while adjusting a polarizing beam splitter optic. The direct causes for the accident included failure to follow safe alignment practices and failure to wear the required laser eyewear protection. Underlying root causes included inadequate on-the-job training and supervision, inadequate adherence to requirements, and inadequate appreciation for dimly visible beams outside the range of 400-700nm. This paper describes how the accident occurred, discusses causes and lessons learned, and describes corrective actions being taken.
Date: January 26, 2011
Creator: Woods, Michael
System: The UNT Digital Library
Laser Safety: A Laser Alignment Practical Training Course (open access)

Laser Safety: A Laser Alignment Practical Training Course

SLAC National Accelerator Laboratory has developed a Laser Alignment Practical Training Course as one of its core laser safety classes. The course is taught to small groups of up to three students and takes 1-3 hours to complete. This practical course is not a substitute for site-specific On-the-Job Training; it does, however, provide a good introduction in core laser safety practices that can be broadly applied. Alignment and diagnostic tasks are performed with low power lasers. Students learn safe alignment and diagnostic techniques and how to avoid common mistakes that might lead to an accident. The class is taught by laser supervisors, enabling them to assess the skill level of new laser personnel and determine the subsequent level of supervision needed. The course has six alignment tasks. For each task, discussion points are given for the instructor to review with the students. The optics setup includes different wavelength lasers, a beam expander, mirrors, irises, a periscope, a beam-splitting polarizer and a diffraction grating. Diagnostic tools include viewing cards, an IR viewer and a ccd camera. Laser eyewear is available to block some laser wavelengths in the setup.
Date: January 26, 2011
Creator: Woods, Michael & Edstrom, Steve
System: The UNT Digital Library
HANFORD RIVER PROTECTION PROJECT ENHANCED MISSION PLANNING THROUGH INNOVATIVE TOOLS LIFECYCLE COST MODELING AND AQUEOUS THERMODYNAMIC MODELING - 12134 (open access)

HANFORD RIVER PROTECTION PROJECT ENHANCED MISSION PLANNING THROUGH INNOVATIVE TOOLS LIFECYCLE COST MODELING AND AQUEOUS THERMODYNAMIC MODELING - 12134

Two notable modeling efforts within the Hanford Tank Waste Operations Simulator (HTWOS) are currently underway to (1) increase the robustness of the underlying chemistry approximations through the development and implementation of an aqueous thermodynamic model, and (2) add enhanced planning capabilities to the HTWOS model through development and incorporation of the lifecycle cost model (LCM). Since even seemingly small changes in apparent waste composition or treatment parameters can result in large changes in quantities of high-level waste (HLW) and low-activity waste (LAW) glass, mission duration or lifecycle cost, a solubility model that more accurately depicts the phases and concentrations of constituents in tank waste is required. The LCM enables evaluation of the interactions of proposed changes on lifecycle mission costs, which is critical for decision makers.
Date: January 26, 2012
Creator: KL, PIERSON & FL, MEINERT
System: The UNT Digital Library
FULL SCALE TESTING TECHNOLOGY MATURATION OF A THIN FILM EVAPORATOR FOR HIGH-LEVEL LIQUID WASTE MANAGEMENT AT HANFORD - 12125 (open access)

FULL SCALE TESTING TECHNOLOGY MATURATION OF A THIN FILM EVAPORATOR FOR HIGH-LEVEL LIQUID WASTE MANAGEMENT AT HANFORD - 12125

Simulant testing of a full-scale thin-film evaporator system was conducted in 2011 for technology development at the Hanford tank farms. Test results met objectives of water removal rate, effluent quality, and operational evaluation. Dilute tank waste simulant, representing a typical double-shell tank supernatant liquid layer, was concentrated from a 1.1 specific gravity to approximately 1.5 using a 4.6 m{sup 2} (50 ft{sup 2}) heated transfer area Rototherm{reg_sign} evaporator from Artisan Industries. The condensed evaporator vapor stream was collected and sampled validating efficient separation of the water. An overall decontamination factor of 1.2E+06 was achieved demonstrating excellent retention of key radioactive species within the concentrated liquid stream. The evaporator system was supported by a modular steam supply, chiller, and control computer systems which would be typically implemented at the tank farms. Operation of these support systems demonstrated successful integration while identifying areas for efficiency improvement. Overall testing effort increased the maturation of this technology to support final deployment design and continued project implementation.
Date: January 26, 2012
Creator: AR, TEDESCHI; JE, CORBETT; RA, WILSON & J, LARKIN
System: The UNT Digital Library
Validity of the thin mask approximation in extreme ultraviolet mask roughness simulations (open access)

Validity of the thin mask approximation in extreme ultraviolet mask roughness simulations

In the case of extreme ultraviolet (EUV) lithography, modeling has shown that reflector phase roughness on the lithographic mask is a significant concern due to the image plan speckle it causes and the resulting line-edge roughness on imaged features. Modeling results have recently been used to determine the requirements for future production worthy masks yielding the extremely stringent specification of 50 pm rms roughness. Owing to the scale of the problem in terms of memory requirements, past modeling results have all been based on the thin mask approximation. EUV masks, however, are inherently three dimensional in nature and thus the question arises as to the validity of the thin mask approximation. Here we directly compare image plane speckle calculation results using the fast two dimensional thin mask model to rigorous finite-difference time-domain results and find the two methods to be comparable.
Date: January 26, 2011
Creator: Naulleau, Patrick & George, Simi
System: The UNT Digital Library
Calibration of energy dispersive x-ray spectrometers for analysis of thin environmental samples (open access)

Calibration of energy dispersive x-ray spectrometers for analysis of thin environmental samples

Four separate techniques for calibrating energy dispersive x-ray spectrometers are described. They include the use of (1) individual evaporated elemental thin-film standards, (2) nebulized multielement standard solution deposits to determine relative elemental sensitivity factors, (3) a semi-empirical approach to calculate relative elemental sensitivity factors, and (4) thick pure element disks. The first three techniques are applicable for a broad range of elements. The utilization of nebulized multielement standard solution deposits, along with an evaporated single element thin-film standard for absolute system calibration, is the most accurate method of the calibration techniques described.
Date: January 26, 1976
Creator: Giauque, R. D.; Garrett, R. B. & Goda, L. Y.
System: The UNT Digital Library
Calibration of a High Resolution Soft X-ray Spectrometer (open access)

Calibration of a High Resolution Soft X-ray Spectrometer

A high resolution grating spectrometer (HRGS) with 2400 line/mm variable line spacing grating for the 10-50 {angstrom} wavelength range has been designed for laser-produced plasma experiments at the Lawrence Livermore National Laboratory (LLNL). The spectrometer has a large radius of curvature, R=44.3 m, is operated at a 2{sup o} grazing angle and can record high signal-to-noise spectra when used with a low-noise, cooled, charge-coupled device detector. The instrument can be operated with a 10-25 {micro}m wide slit to achieve the best spectral resolving power on laser plasma sources, approaching 2000, or in slitless mode with a small symmetrical emission source. Results will be presented for the spectral response of the spectrometer cross-calibrated at the LLNL Electron Beam Ion Trap facility using the broadband x-ray energy EBIT Calorimeter Spectrometer (ECS).
Date: January 26, 2010
Creator: Dunn, J; Beiersdorfer, P; Brown, G V & Magee, E W
System: The UNT Digital Library
Geothermal Program Activities of the Department of Conservation Division of Oil, Gas, and Geothermal Resources (open access)

Geothermal Program Activities of the Department of Conservation Division of Oil, Gas, and Geothermal Resources

None
Date: January 26, 1995
Creator: Guerard, William F., Jr.
System: The UNT Digital Library
Interpretation of pre- and post-fracturing well tests in a geothermal reservoir (open access)

Interpretation of pre- and post-fracturing well tests in a geothermal reservoir

Pre- and post-fracturing well tests in TG-2 well drilled next to the Matsukawa field are interpreted for evaluating effects of a massive hydraulic fracturing treatment. The interpreted data include multiple-step rate tests, a two-step rate test, and falloff tests. Pressure behaviors of massive hydraulic fracturing are matched by a simulator of dynamic fracture option. Fracture parting pressures can be evaluated from the multiple-step rate test data. The multiple-step rates during the massive hydraulic fracturing treatment show that multiple fractures have been induced in sequence. Although the pre-fracturing falloff tests are too short, fracture propagation can be evaluated qualitatively from the falloff data. Interpretation of the falloff test immediately after the MHF suggests that extensive fractures have been created by the MHF, which is verified by simulation. The post-fracturing falloff tests show that the fractures created by the MHF have closed to a great degree.
Date: January 26, 1995
Creator: Arihara, Norio; Fukagawa, Hiroshi; Hyodo, Masami & Abbaszadeh, Maghsood
System: The UNT Digital Library
Are there significant hydrothermal resources in the US part of the Cascade Range? (open access)

Are there significant hydrothermal resources in the US part of the Cascade Range?

The Cascade Range is a geothermal dichotomy. On the one hand, it is an active volcanic arc above a subducting plate and is demonstrably an area of high heat flow. On the other hand, the distribution of hydrothermal manifestations compared to other volcanic arcs is sparse, and the hydrothermal outflow calculated from stream chemistry is low. Several large estimates of undiscovered geothermal resources in the U.S. part of the Cascade Range prepared in the 1970s and early 1980s were based fundamentally on two models of the upper crust. One model assumed that large, partly molten, intrusive bodies exist in the upper 10 km beneath major volcanic centers and serve as the thermal engines driving overlying hydrothermal systems. The other model interpreted the coincident heat-flow and gravity gradients west of the Cascade crest in central Oregon to indicate a partly molten heat source at 10 {+-} 2 km depth extending {approx}30 km west from the axis of the range. Investigations of the past ten years have called both models into question. Large long-lived high-temperature hydrothermal systems at depths <3 km in the U.S. part of the Cascade Range appear to be restricted to silicic domefields at the Lassen volcanic center, Medicine …
Date: January 26, 1995
Creator: Muffler, L.J. Patrick & Guffanti, Marianne
System: The UNT Digital Library
Thermodynamic transient behavior of a geothermal fracture (open access)

Thermodynamic transient behavior of a geothermal fracture

This paper presents a space integrated zero dimensional model that describes the thermodynamic behavior of a geothermal fracture undergoing exploitation. The main assumptions involved are: fluid and energy entering the fracture come from the surrounding matrix, fracture of infinite conductivity, and that the steam and water phases are gravitationally segregated and in thermodynamic equilibrium. The nonlinear equations of mass and energy conservation are numerically solved. A sensitivity analysis on the main parameters that affect this problem was carried out. Water recharge is described by a linear infinite aquifer, and heat flow from the matrix to the fluid was also considered by means of a linear infinite system. The behavior of the system is clearly described for conditions of exploitation in the steam, in the water, or mixed completion in both steam and water zones.
Date: January 26, 1995
Creator: Ascencio, F.; Samaniego, F.; Cinco-Ley, H. & Rivera, J.
System: The UNT Digital Library
Characterization of injection wells in a fractured reservoir using PTS logs, Steamboat Hills Geothermal Field, Nevada, USA (open access)

Characterization of injection wells in a fractured reservoir using PTS logs, Steamboat Hills Geothermal Field, Nevada, USA

The Steamboat Hills Geothermal Field in northwestern Nevada, about 15 km south of Reno, is a shallow (150m to 825m) moderate temperature (155 C to 168 C) liquid-dominated geothermal reservoir situated in highly-fractured granodiorite. Three injection wells were drilled and completed in granodiorite to dispose of spent geothermal fluids from the Steamboat II and III power plants (a 30 MW air-cooled binary-type facility). Injection wells were targeted to depths below 300m to inject spent fluids below producing fractures. First, quasi-static downhole pressure-temperature-spinner (PTS) logs were obtained. Then, the three wells were injection-tested using fluids between 80 C and 106 C at rates from 70 kg/s to 200 kg/s. PTS logs were run both up and down the wells during these injection tests. These PTS surveys have delineated the subsurface fracture zones which will accept fluid. The relative injectivity of the wells was also established. Shut-in interzonal flow within the wells was identified and characterized.
Date: January 26, 1995
Creator: Goranson, Colin & Combs, Jim
System: The UNT Digital Library
Effect of sorption/curved interface thermodynamics on pressure transient (open access)

Effect of sorption/curved interface thermodynamics on pressure transient

A simulation model capable of handling the effects of sorption was constructed. It accounts for the curved interface thermodynamics associated with adsorption and desorption. Data from several laboratory experiments were used to verify the model. The results indicated that simulation runs using sorption isotherms adequately model the pressure transient behavior observed in the laboratory experiments. Dry steam models severely underestimated the effective compressibility. Models using flat-interface (steam table) thermodynamics over-estimated the compressibility of the system, indicated by slower than actual rate of pressure transient propagation.
Date: January 26, 1995
Creator: Lim, K.T. & Aziz, K.
System: The UNT Digital Library
X-ray tomography of preserved samples from The Geysers scientific corehole (open access)

X-ray tomography of preserved samples from The Geysers scientific corehole

Approximately 800 ft. of continuous core was recovered from borehole SB-15 D (on unit 15, near the site of the abandoned Geysers Resort) during a recently completed drilling operation funded by the USDOE. Sections of this core were collected at 50 ft intervals for subsequent examination as drilling proceeded. Five foot sections were not removed at the drill site, but were sealed in the innermost sleeve of a triple tube coring system to minimize drying and disturbance of the core. All cores remained sealed and were radiographed within 72 hours of drilling: the five foot core from near 1400 ft. was scanned within 18 hours of drilling. A third generation x-ray scanner, which uses high energy radiation to penetrate the aluminum sleeve and 3.5 inch cores, was used to make preliminary radiographs and to collect multiple views of the sample as the core is rotated in front of the beam. True three dimensional tomographs are then reconstructed from the data. At present, the images have a spatial resolution of approximately 140 micrometers and can resolve contrast differences of 0.2%. The tomographs clearly show differences in lithology with depth in the reservoir. Partially filled fractures, vein selvage and vuggy porosity are …
Date: January 26, 1995
Creator: Bonner, B. P.; Roberts, J. J.; Schneberk, D. J.; Marsh, A.; Ruddle, C. & Updike, E.
System: The UNT Digital Library