Exceptional Ground Accelerations and Velocities Caused by Earthquakes (open access)

Exceptional Ground Accelerations and Velocities Caused by Earthquakes

This project aims to understand the characteristics of the free-field strong-motion records that have yielded the 100 largest peak accelerations and the 100 largest peak velocities recorded to date. The peak is defined as the maximum magnitude of the acceleration or velocity vector during the strong shaking. This compilation includes 35 records with peak acceleration greater than gravity, and 41 records with peak velocities greater than 100 cm/s. The results represent an estimated 150,000 instrument-years of strong-motion recordings. The mean horizontal acceleration or velocity, as used for the NGA ground motion models, is typically 0.76 times the magnitude of this vector peak. Accelerations in the top 100 come from earthquakes as small as magnitude 5, while velocities in the top 100 all come from earthquakes with magnitude 6 or larger. Records are dominated by crustal earthquakes with thrust, oblique-thrust, or strike-slip mechanisms. Normal faulting mechanisms in crustal earthquakes constitute under 5% of the records in the databases searched, and an even smaller percentage of the exceptional records. All NEHRP site categories have contributed exceptional records, in proportions similar to the extent that they are represented in the larger database.
Date: January 17, 2008
Creator: Anderson, John
Object Type: Report
System: The UNT Digital Library
Invert Effective Thermal Conductivity Calculation (open access)

Invert Effective Thermal Conductivity Calculation

The objective of this calculation is to evaluate the temperature-dependent effective thermal conductivities of a repository-emplaced invert steel set and surrounding ballast material. The scope of this calculation analyzes a ballast-material thermal conductivity range of 0.10 to 0.70 W/m {center_dot} K, a transverse beam spacing range of 0.75 to 1.50 meters, and beam compositions of A 516 carbon steel and plain carbon steel. Results from this calculation are intended to support calculations that identify waste package and repository thermal characteristics for Site Recommendation (SR). This calculation was developed by Waste Package Department (WPD) under Office of Civilian Radioactive Waste Management (OCRWM) procedure AP-3.12Q, Revision 1, ICN 0, Calculations.
Date: March 17, 2000
Creator: Anderson, M. J.; Wade, H. M. & Mitchell, T. L.
Object Type: Report
System: The UNT Digital Library
Fast Neutron Damage Studies on NdFeB Materials (open access)

Fast Neutron Damage Studies on NdFeB Materials

Many materials and electronics need to be tested for the radiation environment expected at linear colliders (LC) since both accelerator and detectors will be subjected to large fluences of hadrons, leptons and {gamma}'s over the life of the facility [1]. While the linacs will be superconducting, there are still many uses for NdFeB in the damping rings, injection and extraction lines and final focus. Our understanding of the situation for rare earth, permanent magnet materials was presented at PAC03 [2]. Our first measurements of fast neutron, stepped doses at the UC Davis McClellan Nuclear Reactor Center (UCD MNRC) were presented at EPAC04 [3]. We have extended the doses, included other manufacturer's samples, and measured induced radioactivities which are discussed in detail.
Date: May 17, 2005
Creator: Anderson, S.; Spencer, J.; Wolf, Z.; /SLAC; Baldwin, A.; Pellett, D. et al.
Object Type: Article
System: The UNT Digital Library
Application of a XMM-Newton EPIC Monte Carlo to Analysis And Interpretation of Data for Abell 1689, RXJ0658-55 And the Centaurus Clusters of Galaxies (open access)

Application of a XMM-Newton EPIC Monte Carlo to Analysis And Interpretation of Data for Abell 1689, RXJ0658-55 And the Centaurus Clusters of Galaxies

We propose a new Monte Carlo method to study extended X-ray sources with the European Photon Imaging Camera (EPIC) aboard XMM Newton. The Smoothed Particle Inference (SPI) technique, described in a companion paper, is applied here to the EPIC data for the clusters of galaxies Abell 1689, Centaurus and RXJ 0658-55 (the ''bullet cluster''). We aim to show the advantages of this method of simultaneous spectral-spatial modeling over traditional X-ray spectral analysis. In Abell 1689 we confirm our earlier findings about structure in temperature distribution and produce a high resolution temperature map. We also confirm our findings about velocity structure within the gas. In the bullet cluster, RXJ 0658-55, we produce the highest resolution temperature map ever to be published of this cluster allowing us to trace what looks like the motion of the bullet in the cluster. We even detect a south to north temperature gradient within the bullet itself. In the Centaurus cluster we detect, by dividing up the luminosity of the cluster in bands of gas temperatures, a striking feature to the north-east of the cluster core. We hypothesize that this feature is caused by a subcluster left over from a substantial merger that slightly displaced the …
Date: April 17, 2007
Creator: Andersson, Karl E.; /SLAC, /Stockholm U.; Peterson, J.R.; /Purdue U. /KIPAC, Menlo Park; Madejski, G.M. & /SLAC /KIPAC, Menlo Park
Object Type: Article
System: The UNT Digital Library
Characterization of Corrosion Damage on Aluminum Fuel Assemblies in Basin Storage (open access)

Characterization of Corrosion Damage on Aluminum Fuel Assemblies in Basin Storage

This paper summarizes the inspections and inspection results in conjunction with the corrosion experience of aluminum-clad SNF in basin storage.
Date: September 17, 2002
Creator: Andes, T.C.
Object Type: Article
System: The UNT Digital Library
Muons and neutrinos at high-energy accelerators (open access)

Muons and neutrinos at high-energy accelerators

Background levels in detectors and radiation problems at future colliders--whether pp, e{sup +}e{sup {minus}} or {mu}{sup +}{mu}{sup {minus}} are in large part determined by the presence of muons. Neutrinos from muon decay at muon colliders or storage rings are highly collimated and propagate outward within a narrowdisk in which significant radiation doses persist out to very large distances. This paper highlights physics models and Monte Carlo algorithms developed mainly for studying these problems as well as some typical results.
Date: August 17, 2000
Creator: Andreas Van Ginneken, Sergei Striganov and Nikolai Mokhov
Object Type: Article
System: The UNT Digital Library
Developments in Oil Shale (open access)

Developments in Oil Shale

None
Date: November 17, 2008
Creator: Andrews, Anthony
Object Type: Report
System: The UNT Digital Library
Hydrogen-filled RF Cavities for Muon Beam Cooling (open access)

Hydrogen-filled RF Cavities for Muon Beam Cooling

Ionization cooling requires low-Z energy absorbers immersed in a strong magnetic field and high-gradient, large-aperture RF cavities to be able to cool a muon beam as quickly as the short muon lifetime requires. RF cavities that operate in vacuum are vulnerable to dark-current- generated breakdown, which is exacerbated by strong magnetic fields, and they require extra safety windows that degrade cooling, to separate RF regions from hydrogen energy absorbers. RF cavities pressurized with dense hydrogen gas will be developed that use the same gas volume to provide the energy absorber and the RF acceleration needed for ionization cooling. The breakdown suppression by the dense gas will allow the cavities to operate in strong magnetic fields. Measurements of the operation of such a cavity will be made as functions of external magnetic field and charged particle beam intensity and compared with models to understand the characteristics of this technology and to develop mitigating strategies if necessary.
Date: April 17, 2009
Creator: Ankenbrandt, Charles
Object Type: Report
System: The UNT Digital Library
Wave Propagation in Jointed Geologic Media (open access)

Wave Propagation in Jointed Geologic Media

Predictive modeling capabilities for wave propagation in a jointed geologic media remain a modern day scientific frontier. In part this is due to a lack of comprehensive understanding of the complex physical processes associated with the transient response of geologic material, and in part it is due to numerical challenges that prohibit accurate representation of the heterogeneities that influence the material response. Constitutive models whose properties are determined from laboratory experiments on intact samples have been shown to over-predict the free field environment in large scale field experiments. Current methodologies for deriving in situ properties from laboratory measured properties are based on empirical equations derived for static geomechanical applications involving loads of lower intensity and much longer durations than those encountered in applications of interest involving wave propagation. These methodologies are not validated for dynamic applications, and they do not account for anisotropic behavior stemming from direcitonal effects associated with the orientation of joint sets in realistic geologies. Recent advances in modeling capabilities coupled with modern high performance computing platforms enable physics-based simulations of jointed geologic media with unprecedented details, offering a prospect for significant advances in the state of the art. This report provides a brief overview of these …
Date: December 17, 2009
Creator: Antoun, T
Object Type: Report
System: The UNT Digital Library
Surfactant Concentration and End Effects on Foam Flow in Porous Media, TR-120 (open access)

Surfactant Concentration and End Effects on Foam Flow in Porous Media, TR-120

This project studies foam flow behavior at a variety of surfactant concentrations using experiments and a numerical model. Thus, the foam behavior examined spans from strong to weak.
Date: January 17, 2001
Creator: Apaydin, Osman G. & Kovscek, Anthony R.
Object Type: Report
System: The UNT Digital Library
Dose potential of sludge contaminated and/or TRU contaminated waste in B-25s for tornado and straight wind events (open access)

Dose potential of sludge contaminated and/or TRU contaminated waste in B-25s for tornado and straight wind events

F and H Tank Farms generate supernate and sludge contaminated Low-Level Waste. The waste is collected, characterized, and packaged for disposal. Before the waste can be disposed of, however, it must be properly characterized. Since the radionuclide distribution in typical supernate is well known, its characterization is relatively straight forward and requires minimal effort. Non-routine waste, including potentially sludge contaminated, requires much more effort to effectively characterize. The radionuclide distribution must be determined. In some cases the waste can be contaminated by various sludge transfers with unique radionuclide distributions. In these cases, the characterization can require an extensive effort. Even after an extensive characterization effort, the container must still be prepared for shipping. Therefore a significant amount of time may elapse from the time the waste is generated until the time of disposal. During the time it is possible for a tornado or high wind scenario to occur. The purpose of this report is to determine the effect of a tornado on potential sludge contaminated waste, or Transuranic (TRU) waste in B-25s [large storage containers], to evaluate the potential impact on F and H Tank Farms, and to help establish a B-25 control program for tornado events.
Date: February 17, 2000
Creator: Aponte, C.I.
Object Type: Report
System: The UNT Digital Library
A stable finite difference method for the elastic wave equation on complex geometries with free surfaces (open access)

A stable finite difference method for the elastic wave equation on complex geometries with free surfaces

The isotropic elastic wave equation governs the propagation of seismic waves caused by earthquakes and other seismic events. It also governs the propagation of waves in solid material structures and devices, such as gas pipes, wave guides, railroad rails and disc brakes. In the vast majority of wave propagation problems arising in seismology and solid mechanics there are free surfaces. These free surfaces have, in general, complicated shapes and are rarely flat. Another feature, characterizing problems arising in these areas, is the strong heterogeneity of the media, in which the problems are posed. For example, on the characteristic length scales of seismological problems, the geological structures of the earth can be considered piecewise constant, leading to models where the values of the elastic properties are also piecewise constant. Large spatial contrasts are also found in solid mechanics devices composed of different materials welded together. The presence of curved free surfaces, together with the typical strong material heterogeneity, makes the design of stable, efficient and accurate numerical methods for the elastic wave equation challenging. Today, many different classes of numerical methods are used for the simulation of elastic waves. Early on, most of the methods were based on finite difference approximations …
Date: December 17, 2007
Creator: Appelo, D & Petersson, N A
Object Type: Article
System: The UNT Digital Library
Zero Energy Windows (open access)

Zero Energy Windows

Windows in the U.S. consume 30 percent of building heating and cooling energy, representing an annual impact of 4.1 quadrillion BTU (quads) of primary energy. Windows have an even larger impact on peak energy demand and on occupant comfort. An additional 1 quad of lighting energy could be saved if buildings employed effective daylighting strategies. The ENERGY STAR{reg_sign} program has made standard windows significantly more efficient. However, even if all windows in the stock were replaced with today's efficient products, window energy consumption would still be approximately 2 quads. However, windows can be ''net energy gainers'' or ''zero-energy'' products. Highly insulating products in heating applications can admit more useful solar gain than the conductive energy lost through them. Dynamic glazings can modulate solar gains to minimize cooling energy needs and, in commercial buildings, allow daylighting to offset lighting requirements. The needed solutions vary with building type and climate. Developing this next generation of zero-energy windows will provide products for both existing buildings undergoing window replacements and products which are expected to be contributors to zero-energy buildings. This paper defines the requirements for zero-energy windows. The technical potentials in terms of national energy savings and the research and development (R&D) status …
Date: May 17, 2006
Creator: Arasteh, Dariush; Selkowitz, Steve; Apte, Josh & LaFrance, Marc
Object Type: Article
System: The UNT Digital Library
Higher-Twist Dynamics in Large Transverse Momentum Hadron Production (open access)

Higher-Twist Dynamics in Large Transverse Momentum Hadron Production

A scaling law analysis of the world data on inclusive large-p{sub {perpendicular}} hadron production in hadronic collisions is carried out. A significant deviation from leading-twist perturbative QCD predictions at next-to-leading order is reported. The observed discrepancy is largest at high values of x{sub {perpendicular}} = 2p{sub {perpendicular}}/{radical}s. In contrast, the production of prompt photons and jets exhibits the scaling behavior which is close to the conformal limit, in agreement with the leading-twist expectation. These results bring evidence for a non-negligible contribution of higher-twist processes in large-p{sub {perpendicular}} hadron production in hadronic collisions, where the hadron is produced directly in the hard subprocess rather than by gluon or quark jet fragmentation. Predictions for scaling exponents at RHIC and LHC are given, and it is suggested to trigger the isolated large-p{sub {perpendicular}} hadron production to enhance higher-twist processes.
Date: December 17, 2009
Creator: Arleo, Francois; Brodsky, Stanley J.; Hwang, Dae Sung & Sickles, Anne M.
Object Type: Article
System: The UNT Digital Library
Input and Results of the Base Case Saturated Zone Flow and Transport Model for TSPA (open access)

Input and Results of the Base Case Saturated Zone Flow and Transport Model for TSPA

None
Date: October 17, 2001
Creator: Arnold, B. W.
Object Type: Report
System: The UNT Digital Library
Structural Investigations of Surfaces and Orientation-SpecificPhenomena in Nanocrystals and Their Assemblies (open access)

Structural Investigations of Surfaces and Orientation-SpecificPhenomena in Nanocrystals and Their Assemblies

Studies of colloidal nanocrystals and their assemblies are presented. Two of these studies concern the atomic-level structural characterization of the surfaces, interfaces, and interiors present in II-VI semiconductor nanorods. The third study investigates the crystallographic arrangement of cobalt nanocrystals in self-assembled aggregates. Crystallographically-aligned assemblies of colloidal CdSe nanorods are examined with linearly-polarized Se-EXAFS spectroscopy, which probes bonding along different directions in the nanorod. This orientation-specific probe is used, because it is expected that the presence of specific surfaces in a nanorod might cause bond relaxations specific to different crystallographic directions. Se-Se distances are found to be contracted along the long axis of the nanorod, while Cd-Se distances display no angular dependence, which is different from the bulk. Ab-initio density functional theory calculations upon CdSe nanowires indicate that relaxations on the rod surfaces cause these changes. ZnS/CdS-CdSe core-shell nanorods are studied with Se, Zn, Cd, and S X-ray absorption spectroscopy (XAS). It is hypothesized that there are two major factors influencing the core and shell structures of the nanorods: the large surface area-to-volume ratio, and epitaxial strain. The presence of the surface may induce bond rearrangements or relaxations to minimize surface energy; epitaxial strain might cause the core and shell lattices …
Date: June 17, 2006
Creator: Aruguete, Deborah Michiko
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Driving Mechanism of SOL Plasma Flow and Effects on the Divertor Performance in JT-60U (open access)

Driving Mechanism of SOL Plasma Flow and Effects on the Divertor Performance in JT-60U

None
Date: May 17, 2004
Creator: Asakura, N.; Takenaga, H.; Sakurai, S.; Porter, G.; Rognlien, T.; Rensink, M. et al.
Object Type: Article
System: The UNT Digital Library
Phase I Archaeological Survey of Parcel ED-3 and Historic Assessement of the Happy Valley Worker Camp Roane County, Tennessee (open access)

Phase I Archaeological Survey of Parcel ED-3 and Historic Assessement of the Happy Valley Worker Camp Roane County, Tennessee

Parcel ED-3 was the location of a portion of 'Happy Valley', a temporary worker housing area occupied from 1943 to 1947 during the construction of the K-25 Oak Ridge Gaseous Diffusion Plant. The project was carried out under subcontract for the Department of Energy. The survey report will be used in the preparation of an Environmental Assessment under the National Environmental Policy Act (NEPA). New South Associates conducted a Phase I Archaeological Survey of Parcel ED-3 at the US Department of Energy's Oak Ridge Reservation in Roane County, Tennessee. The survey was conducted in two parts. The first survey was carried out in 2008 and covered an area measuring approximately 110 acres. The second survey took place in 2009 and focused on 72 acres west of the first survey area. The objective of the surveys was to identify any archaeological remains associated with Happy Valley and any additional sites on the property and to assess these sites for National Register eligibility. New South Associates also conducted a historic assessment to gather information on Happy Valley. This historic assessment was used in conjunction with the archaeological survey to evaluate the significance of the Happy Valley site. Archaeological remains of Happy Valley …
Date: August 17, 2009
Creator: Associates, New South
Object Type: Report
System: The UNT Digital Library
Properties of Ellipticity Correlation with Atmospheric Structure From Gemini South (open access)

Properties of Ellipticity Correlation with Atmospheric Structure From Gemini South

Cosmic shear holds great promise for a precision independent measurement of {Omega}{sub m}, the mass density of the universe relative to the critical density. The signal is expected to be weak, so a thorough understanding of systematic effects is crucial. An important systematic effect is the atmosphere: shear power introduced by the atmosphere is larger than the expected signal. Algorithms exist to extract the cosmic shear from the atmospheric component, though a measure of their success applied to a range of seeing conditions is lacking. To gain insight into atmospheric shear, Gemini South imaging in conjunction with ground condition and satellite wind data were obtained. We find that under good seeing conditions Point-Spread-Function (PSF) correlations persist well beyond the separation typical of high-latitude stars. Under these conditions, ellipticity residuals based on a simple PSF interpolation can be reduced to within a factor of a few of the shot-noise induced ellipticity floor. We also find that the ellipticity residuals are highly correlated with wind direction. Finally, we correct stellar shapes using a more sophisticated procedure and generate shear statistics from stars. Under all seeing conditions in our data set the residual correlations lie everywhere below the target signal level. For good …
Date: January 17, 2007
Creator: Asztalos, Stephen J.; de Vries, W. H.; Rosenberg, L. J.; Treadway, T.; Burke, D.; Claver, C. et al.
Object Type: Article
System: The UNT Digital Library
Final Report - Novel Approach to Non-Precious Metal Catalysts (open access)

Final Report - Novel Approach to Non-Precious Metal Catalysts

This project was directed at reducing the dependence of PEM fuel cells catalysts on precious metals. The primary motivation was to reduce the cost of the fuel cell stack as well as the overall system cost without loss of performance or durability. Platinum is currently the catalyst of choice for both the anode & the cathode. However, the oxygen reduction reaction (ORR) which takes place on the cathode is an inherently slower reaction compared to the hydrogen oxidation reaction (HOR) which takes place on the anode. Therefore, more platinum is needed on the cathode than on the anode to achieve suitable fuel cell performance. As a result, developing a replacement for platinum on the cathode side will have a larger impact on overall stack cost. Thus, the specific objectives of the project, as stated in the solicitation, were to produce non-precious metal (NPM) cathode catalysts which reduce dependence on precious metals (especially Pt), perform as well as conventional precious metal catalysts currently in use in MEAs, cost 50% less compared to a target of 0.2 g Pt/peak kW, & demonstrate durability of greater than 2000 hours with less than 10% power degradation. During the term of the project, DOE refined …
Date: November 17, 2007
Creator: Atanasoski, Radoslav
Object Type: Report
System: The UNT Digital Library
Melt processing of Yb-123 tapes (open access)

Melt processing of Yb-123 tapes

The innovation of a simple, scalable process for manufacturing long-length conductors of HTS is essential to potential commercial applications such as power cables, magnets, and transformers. In this paper the authors demonstrate that melt processing of Yb-123 tapes made by the PIT route is an alternative to the coated conductor and Bi-2223 PIT tape fabrication techniques. Ag-clad Yb-123 tapes were fabricated by groove rolling and subsequently, melt processed in different oxygen partial pressures in a zone-melting furnace with a gradient of 140 C/cm. The transition temperatures measured were found to be around 81 K undermost processing conditions. EPMA of the tapes processed under different conditions show the 123 phase to be Ba deficient and Cu and Yb rich. Critical current was measured at various temperatures from 77 K to 4.2 K. The J{sub c} increased with decrease in pO{sub 2}. The highest I{sub c} obtained was 52 A at 4.2 K.
Date: February 17, 2000
Creator: Athur, S. P.; Balachandran, U. & Salama, K.
Object Type: Article
System: The UNT Digital Library
Atmospheric Radiation Measurement Program Facilities Newsletter, December 1999 (open access)

Atmospheric Radiation Measurement Program Facilities Newsletter, December 1999

Monthly newsletter discussing news and activities related to the Atmospheric Radiation Measurement Program, articles about weather and atmospheric phenomena, and other related topics.
Date: January 17, 2000
Creator: Atmospheric Radiation Measurement Program (U.S.)
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
Final Technical Report for University of Michigan Industrial Assessment Center (open access)

Final Technical Report for University of Michigan Industrial Assessment Center

The UM Industrial Assessment Center assisted 119 primary metals, automotive parts, metal casting, chemicals, forest products, agricultural, and glass manufacturers in Michigan, Ohio and Indiana to become more productive and profitable by identifying and recommending specific measures to improve energy efficiency, reduce waste and increase productivity. This directly benefits the environment by saving a total of 309,194 MMBtu of energy resulting in reduction of 0.004 metric tons of carbon emissions. The $4,618,740 implemented cost savings generated also saves jobs that are evaporating from the manufacturing industries in the US. Most importantly, the UM Industrial Assessment Center provided extremely valuable energy education to forty one UM graduate and undergraduate students. The practical experience complements their classroom education. This also has a large multiplier effect because the students take the knowledge and training with them.
Date: April 17, 2007
Creator: Atreya, Arvind
Object Type: Report
System: The UNT Digital Library
Branching Fraction Measurement of B0 to D(*)-pi+and B- to D(*)0pi+ and Isospin Analyses of B to D(*)pi Decays (open access)

Branching Fraction Measurement of B0 to D(*)-pi+and B- to D(*)0pi+ and Isospin Analyses of B to D(*)pi Decays

Using 65 million {Upsilon}(4S) {yields} B{bar B} events collected with the BABAR detector at the PEP-II e{sup +}e{sup -} storage ring at the Stanford Linear Accelerator Center, they measure the color-favored branching fractions {Beta}({bar B}{sup 0} {yields} D{sup +}{pi}{sup -}) = (2.63 {+-} 0.05 {+-} 0.22) x 10{sup -3}, {Beta}({bar B}{sup 0} {yields} D*{sup +}{pi}{sup -}) = (2.79 {+-} 0.08 {+-} 0.18) x 10{sup -3}, {Beta}(B{sup -} {yields} D{sup 0}{pi}{sup -}) = (4.90 {+-} 0.07 {+-} 0.23) x 10{sup -3} and {Beta}(B{sup -} {yields} D*{sup 0} {pi}{sup -}) = (5.52 {+-} 0.17 {+-} 0.43) x 10{sup -3}, where the first error is statistical and the second is systematic. With these results and the current world average for the branching fraction for the color-suppressed decay {bar B}{sup 0} {yields} D{sup (*)0}{pi}{sup 0}, the cosines of the strong phase difference {delta} between the I = 1/2 and I = 3/2 isospin amplitudes are determined to be cos{sigma} = 0.860{sub -0.006-0.028}{sup +0.007+0.029} for the {bar B} {yields} D{pi} process and cos{sigma} = 0.917{sub -0.016-0.051}{sup +0.018+0.059} for the {bar B} {yields} D*{pi} process. The results for cos{delta} suggest that final-state interactions are presented in the D{pi} system.
Date: October 17, 2006
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library