Development and Demonstration of a High Efficiency, Rapid Heating, Low NOx Alternative to Conventional Heating of Round Steel Shapes, Steel Substrate (Strip) and Coil Box Transfer Bars (open access)

Development and Demonstration of a High Efficiency, Rapid Heating, Low NOx Alternative to Conventional Heating of Round Steel Shapes, Steel Substrate (Strip) and Coil Box Transfer Bars

Direct Flame Impingement involves the use of an array of very high-velocity flame jets impinging on a work piece to rapidly heat the work piece. The predominant mode of heat transfer is convection. Because of the locally high rate of heat transfer at the surface of the work piece, the refractory walls and exhaust gases of a DFI furnace are significantly cooler than in conventional radiant heating furnaces, resulting in high thermal efficiency and low NOx emissions. A DFI furnace is composed of a successive arrangement of heating modules through or by which the work piece is conveyed, and can be configured for square, round, flat, and curved metal shapes (e.g., billets, tubes, flat bars, and coiled bars) in single- or multi-stranded applications.
Date: January 25, 2010
Creator: Kurek, Harry & Wagner, John
Object Type: Report
System: The UNT Digital Library
Slope Stability Evaluation and Equipment Setback Distances for Burial Ground Excavations (open access)

Slope Stability Evaluation and Equipment Setback Distances for Burial Ground Excavations

After 1970 Transuranic (TRU) and suspect TRU waste was buried in the ground with the intention that at some later date the waste would be retrieved and processed into a configuration for long term storage. To retrieve this waste the soil must be removed (excavated). Sloping the bank of the excavation is the method used to keep the excavation from collapsing and to provide protection for workers retrieving the waste. The purpose of this paper is to document the minimum distance (setback) that equipment must stay from the edge of the excavation to maintain a stable slope. This evaluation examines the equipment setback distance by dividing the equipment into two categories, (1) equipment used for excavation and (2) equipment used for retrieval. The section on excavation equipment will also discuss techniques used for excavation including the process of benching. Calculations 122633-C-004, 'Slope Stability Analysis' (Attachment A), and 300013-C-001, 'Crane Stability Analysis' (Attachment B), have been prepared to support this evaluation. As shown in the calculations the soil has the following properties: Unit weight 110 pounds per cubic foot; and Friction Angle (natural angle of repose) 38{sup o} or 1.28 horizontal to 1 vertical. Setback distances are measured from the top …
Date: March 25, 2010
Creator: Mcshane, D. S.
Object Type: Report
System: The UNT Digital Library
The AGS with four helical magnets (open access)

The AGS with four helical magnets

The idea of using multiple partial helical magnets was applied successfully to the AGS synchrotron, to preserve the proton beam polarization. In this paper we explore in details the idea of using four helical magnets placed symmetrically in the AGS ring. This modification provides many advantages over the present setup of the AGS that uses two partial helical magnets. First, it provides a larger 'spin tune gap' for the placement of the vertical betatron tune of the AGS during acceleration, second, the vertical spin direction during the beam injection and extraction is closer to vertical, third, the symmetric placement of the snakes allows for a better control of the AGS optics, and for reduced values of the beta and eta functions, especially near injection, fourth, the optical properties of the helical magnets also favor the placement of the horizontal betatron tune in the 'spin tune gap', thus eliminating the horizontal spin resonances. In this paper we provide results on the spin tune and on the optics of the AGS with four partial helical magnets, and we compare these results with the present setup of the AGS that uses two partial helical magnets.
Date: February 25, 2010
Creator: Tsoupas, N.; Huang, H.; MacKay, W. W.; Roser, T. & Trbojevic, D.
Object Type: Report
System: The UNT Digital Library
UPWARD MOVEMENT OF PLUTONIUM TO SURFACE SEDIMENTS DURING AN 11-YEAR FIELD STUDY (open access)

UPWARD MOVEMENT OF PLUTONIUM TO SURFACE SEDIMENTS DURING AN 11-YEAR FIELD STUDY

An 11-y lysimeter study was established to monitor the movement of Pu through vadose zone sediments. Sediment Pu concentrations as a function of depth indicated that some Pu moved upward from the buried source material. Subsequent numerical modeling suggested that the upward movement was largely the result of invading grasses taking up the Pu and translocating it upward. The objective of this study was to determine if the Pu of surface sediments originated from atmosphere fallout or from the buried lysimeter source material (weapons-grade Pu), providing additional evidence that plants were involved in the upward migration of Pu. The {sup 240}Pu/{sup 239}Pu and {sup 242}Pu/{sup 239}Pu atomic fraction ratios of the lysimeter surface sediments, as determined by Thermal Ionization Mass Spectroscopy (TIMS), were 0.063 and 0.00045, respectively; consistent with the signatures of the weapons-grade Pu. Our numerical simulations indicate that because plants create a large water flux, small concentrations over multiple years may result in a measurable accumulation of Pu on the ground surface. These results may have implications on the conceptual model for calculating risk associated with long-term stewardship and monitored natural attenuation management of Pu contaminated subsurface and surface sediments.
Date: January 25, 2010
Creator: Kaplan, D.; Beals, D.; Cadieux, J. & Halverson, J.
Object Type: Article
System: The UNT Digital Library
Holbrook Substation Superconductor Cable System, Long Island, New York Final Report (open access)

Holbrook Substation Superconductor Cable System, Long Island, New York Final Report

The LIPA Superconductor project broke ground on July 4, 2006, was first energized on April 22, 2008 (Earth Day) and was commissioned on June 25, 2008. Since commissioning, up until early March, 2009, there were numerous refrigeration events that impacted steady state operations. This led to the review of the alarms that were being generated and a rewrite of the program logic in order to decrease the hypersensitivity surrounding these alarms. The high temperature superconductor (HTS) cable was energized on March 5, 2009 and ran uninterrupted until a human error during a refrigeration system switchover knocked the cable out of the grid in early February 2010. The HTS cable was in the grid uninterrupted from March 5, 2009 to February 4, 2010. Although there have been refrigeration events (propagated mainly by voltage sags/surges) during this period, the system was able to automatically switch over from the primary to the backup refrigeration system without issue as required during this period. On February 4, 2010, when switching from the backup over to the primary refrigeration system, two rather than one liquid nitrogen pumps were started inadvertently by a human error (communication) causing an overpressure in the cable cooling line. This in turn …
Date: June 25, 2010
Creator: Maguire, James & McNamara, Joseph
Object Type: Report
System: The UNT Digital Library
Accelerator Production Options for 99MO (open access)

Accelerator Production Options for 99MO

Shortages of {sup 99}Mo, the most commonly used diagnostic medical isotope, have caused great concern and have prompted numerous suggestions for alternate production methods. A wide variety of accelerator-based approaches have been suggested. In this paper we survey and compare the various accelerator-based approaches.
Date: August 25, 2010
Creator: Bertsche, Kirk
Object Type: Article
System: The UNT Digital Library
Forming Limits of Weld Metal in Aluminum Alloys and Advanced High-Strength Steels (open access)

Forming Limits of Weld Metal in Aluminum Alloys and Advanced High-Strength Steels

This work characterizes the mechanical properties of DP600 laser welded TWBs (1 mm-1.5 mm) near and in the weld, as well as their limits of formability. The approach uses simple uniaxial experiments to measure the variability in the forming limits of the weld region, and uses a theoretical forming limit diagram calculation to establish a probabilistic distribution of weld region imperfection using an M-K method approach
Date: October 25, 2010
Creator: Stephens, Elizabeth V.; Smith, Mark T.; Grant, Glenn J. & Davies, Richard W.
Object Type: Report
System: The UNT Digital Library
Principal Component Analysis of Multi Spectral Data for Near Real Time Skin Chromophore Mapping (open access)

Principal Component Analysis of Multi Spectral Data for Near Real Time Skin Chromophore Mapping

None
Date: May 25, 2010
Creator: Kainerstorfer, J M; Ehler, M; Amyot, F; Hassan, M; Demos, S G; Chernomordik, V et al.
Object Type: Article
System: The UNT Digital Library
In Situ X-Ray Diffraction of the Delta to Alpha-Prime Transformation in Pu-Ga Alloys (open access)

In Situ X-Ray Diffraction of the Delta to Alpha-Prime Transformation in Pu-Ga Alloys

None
Date: May 25, 2010
Creator: Blobaum, K. J.; Jeffries, J. R.; Wall, M. A.; Cynn, H.; Evans, W. J. & Schwartz, A. J.
Object Type: Article
System: The UNT Digital Library
Bunch length effects in the beam-beam compensation with an electron lens (open access)

Bunch length effects in the beam-beam compensation with an electron lens

Electron lenses for the head-on beam-beam compensation are under construction at the Relativistic Heavy Ion Collider. The bunch length is of the same order as the {beta}-function at the interaction point, and a proton passing through another proton bunch experiences a substantial phase shift which modifies the beam-beam interaction. We review the effect of the bunch length in the single pass beam-beam interaction, apply the same analysis to a proton passing through a long electron lens, and study the single pass beam-beam compensation with long bunches. We also discuss the beam-beam compensation of the electron beam in an electron-ion collider ring.
Date: February 25, 2010
Creator: Fischer, W.; Luo, Y. & Montag, C.
Object Type: Report
System: The UNT Digital Library
The added economic and environmental value of plug-in electric vehicles connected to commercial building microgrids (open access)

The added economic and environmental value of plug-in electric vehicles connected to commercial building microgrids

Connection of electric storage technologies to smartgrids or microgrids will have substantial implications for building energy systems. In addition to potentially supplying ancillary services directly to the traditional centralized grid (or macrogrid), local storage will enable demand response. As an economically attractive option, mobile storage devices such as plug-in electric vehicles (EVs) are in direct competition with conventional stationary sources and storage at the building. In general, it is assumed that they can improve the financial as well as environmental attractiveness of renewable and fossil based on-site generation (e.g. PV, fuel cells, or microturbines operating with or without combined heat and power). Also, mobile storage can directly contribute to tariff driven demand response in commercial buildings. In order to examine the impact of mobile storage on building energy costs and carbon dioxide (CO2) emissions, a microgrid/distributed-energy-resources (DER) adoption problem is formulated as a mixed-integer linear program with minimization of annual building energy costs applying CO2 taxes/CO2 pricing schemes. The problem is solved for a representative office building in the San Francisco Bay Area in 2020. By using employees' EVs for energy management, the office building can arbitrage its costs. But since the car battery lifetime is reduced, a business model …
Date: August 25, 2010
Creator: Stadler, Michael; Momber, Ilan; Megel, Olivier; Gomez, Tomás; Marnay, Chris; Beer, Sebastian et al.
Object Type: Article
System: The UNT Digital Library
Fiber Accelerating Structures (open access)

Fiber Accelerating Structures

One of the options for future particle accelerators are photonic band gap (PBG) fiber accelerators. PBG fibers are specially designed optical fibers that use lasers to excite an electric field that is used to accelerate electrons. To improve PBG accelerators, the basic parameters of the fiber were tested to maximize defect size and acceleration. Using the program CUDOS, several accelerating modes were found that maximized these parameters for several wavelengths. The design of multiple defects, similar to having closely bound fibers, was studied to find possible coupling or the change of modes. The amount of coupling was found to be dependent on distance separated. For certain distances accelerating coupled modes were found and examined. In addition, several non-periodic fiber structures were examined using CUDOS. The non-periodic fibers produced several interesting results and promised more modes given time to study them in more detail.
Date: August 25, 2010
Creator: Hammond, Andrew P. & /SLAC, /Reed Coll.
Object Type: Report
System: The UNT Digital Library
Limiting Accretion onto Massive Stars by Fragmentation-Induced Starvation (open access)

Limiting Accretion onto Massive Stars by Fragmentation-Induced Starvation

Massive stars influence their surroundings through radiation, winds, and supernova explosions far out of proportion to their small numbers. However, the physical processes that initiate and govern the birth of massive stars remain poorly understood. Two widely discussed models are monolithic collapse of molecular cloud cores and competitive accretion. To learn more about massive star formation, we perform simulations of the collapse of rotating, massive, cloud cores including radiative heating by both non-ionizing and ionizing radiation using the FLASH adaptive mesh refinement code. These simulations show fragmentation from gravitational instability in the enormously dense accretion flows required to build up massive stars. Secondary stars form rapidly in these flows and accrete mass that would have otherwise been consumed by the massive star in the center, in a process that we term fragmentation-induced starvation. This explains why massive stars are usually found as members of high-order stellar systems that themselves belong to large clusters containing stars of all masses. The radiative heating does not prevent fragmentation, but does lead to a higher Jeans mass, resulting in fewer and more massive stars than would form without the heating. This mechanism reproduces the observed relation between the total stellar mass in the cluster …
Date: August 25, 2010
Creator: Peters, Thomas; /ZAH, Heidelberg; Klessen, Ralf S.; /ZAH, Heidelberg /KIPAC, Menlo Park; Mac Low, Mordecai-Mark; Hist., /Amer. Museum Natural et al.
Object Type: Article
System: The UNT Digital Library
Coherence Properties of the LCLS (open access)

Coherence Properties of the LCLS

The LINAC Coherent Light Source (LCLS), an X-Ray free-electron laser(FEL) based on the self amplified spontaneous emission principle, has recently come on-line. For many users it is desirable to have an idea of the level of transverse coherence of the X-Ray beam produced. In this paper, we analyze the output of GENESIS simulations of electrons traveling through the FEL. We first test the validity of an approach that ignores the details of how the beam was produced, and instead, by assuming a Gaussian-Schell model of transverse coherence, predicts the level of transverse coherence simply through looking at the beam radius at several longitudinal slices. We then develop a Markov chain Monte Carlo approach to calculating the degree of transverse coherence, which offers a {approx}100-fold speedup compared to the brute-force algorithm previously in use. We find the beam highly coherent. Using a similar Markov chain Monte Carlo approach, we estimate the reasonability of assuming the beam to have a Gaussian-Schell model of transverse coherence, with inconclusive results.
Date: August 25, 2010
Creator: Ocko, Samuel
Object Type: Report
System: The UNT Digital Library
Vector Boson Jets with BlackHat and Sherpa (open access)

Vector Boson Jets with BlackHat and Sherpa

We review recent NLO QCD results for W, Z + 3-jet production at hadron colliders, computing using BlackHat and SHERPA, and including also some new results for Z + 3-jet production for the LHC at 7 TeV. We report new progress towards the NLO cross section for W + 4-jet production. In particular, we show that the virtual matrix elements produced by BlackHat are numerically stable. We also show that with an improved integrator and tree-level matrix elements from BlackHat, SHERPA produces well-behaved real-emission contributions. As an illustration, we present the real-emission contributions - including dipole-subtraction terms - to the p{sub T} distribution of the fourth jet, for a single subprocess with the maximum number of gluons.
Date: August 25, 2010
Creator: Berger, C.F.; /MIT, LNS; Bern, Z.; /UCLA; Dixon, Lance J.; /SLAC et al.
Object Type: Article
System: The UNT Digital Library
Complete Genome Sequence of Denitrovibrio Acetiphilus Type Strain (N2460T) (open access)

Complete Genome Sequence of Denitrovibrio Acetiphilus Type Strain (N2460T)

Denitrovibrio acetiphilus Myhr and Torsvik 2000 is the type species of the genus Denitrovibrio in the bacterial family Deferribacteraceae. It is of phylogenetic interest because there are only six genera described in the family Deferribacteraceae. D. acetiphilus was isolated as a representative of a population reducing nitrate to ammonia in a laboratory column simulating the conditions in off-shore oil recovery fields. When nitrate was added to this column undesirable hydrogen sulfide production was stopped because the sulfate reducing populations were superseded by these nitrate reducing bacteria. Here we describe the features of this marine, mesophilic, obligately anaerobic organism respiring by nitrate reduction, together with the complete genome sequence, and annotation. This is the second complete genome sequence of the order Deferribacterales and the class Deferribacteres, which is the sole class in the phylum Deferribacteres. The 3,222,077 bp genome with its 3,034 protein-coding and 51 RNA genes is part of the Genomic Encyclopedia of Bacteria and Archaea project.
Date: June 25, 2010
Creator: Kiss, Hajnalka; Lang, Elke; Lapidus, Alla; Copeland, Alex; Nolan, Matt; Glavina Del Rio, Tijana et al.
Object Type: Article
System: The UNT Digital Library
Optimization of the LCLS Single Pulse Shutter (open access)

Optimization of the LCLS Single Pulse Shutter

A mechanical shutter which operates on demand is used to isolate a single pulse from a 120 Hz X-ray source. This is accomplished with a mechanical shutter which is triggered on demand with frequencies ranging from 0 to 10 Hz. The single pulse shutter is an iron blade that oscillates on a pivot in response to a force generated by a pair of pulsed electromagnets (current driven teeter-totter). To isolate an individual pulse from the X-ray beam, the motion of the mechanical shutter should be synchronized in such a way that it allows a single pulse to pass through the aperture and blocks the other incoming pulses. Two consecutive pulses are only {approx} 8 ms apart and the shutter is required to complete one full cycle such that no two pulses pass through the opening. Also the opening of the shutter blade needs to be at least 4 mm so that a 1 mm diameter rms Gaussian beam can pass through without modulation. However, the 4 mm opening is difficult to obtain due to blade rebound and oscillation of the blade after colliding with the electromagnet. The purpose of this project is to minimize and/or totally eliminate the rebound of …
Date: August 25, 2010
Creator: Adera, Solomon & /Georgia Tech., Atlanta /SLAC
Object Type: Report
System: The UNT Digital Library
First Demonstration of the Echo-Enabled Harmonic Generation Technique for Short-Wavelength Seeded Free Electron Lasers (open access)

First Demonstration of the Echo-Enabled Harmonic Generation Technique for Short-Wavelength Seeded Free Electron Lasers

We report the first experimental demonstration of the echo-enabled harmonic generation (EEHG) technique which holds great promise for generation of high power, fully coherent short-wavelength radiation. In this experiment, coherent radiation at the 3rd and 4th harmonic of the second seed laser is generated from the so-called beam echo effect. The experiment confirms the physics behind this technique and paves the way for applying the EEHG technique for seeded x-ray free electron lasers.
Date: August 25, 2010
Creator: Xiang, D.; Colby, E.; Dunning, M.; Gilevich, S.; Hast, C.; Jobe, K. et al.
Object Type: Article
System: The UNT Digital Library
Essence of the Vacuum Quark Condensate (open access)

Essence of the Vacuum Quark Condensate

We show that the chiral-limit vacuum quark condensate is qualitatively equivalent to the pseudoscalar meson leptonic decay constant in the sense that they are both obtained as the chiral-limit value of well-defined gauge-invariant hadron-to-vacuum transition amplitudes that possess a spectral representation in terms of the current-quark mass. Thus, whereas it might sometimes be convenient to imagine otherwise, neither is essentially a constant mass-scale that fills all spacetime. This means, in particular, that the quark condensate can be understood as a property of hadrons themselves, which is expressed, for example, in their Bethe-Salpeter or light-front wavefunctions.
Date: August 25, 2010
Creator: Brodsky, Stanley J.; /SLAC /Southern Denmark U., CP3-Origins; Roberts, Craig D.; /Argonne, PHY /Peking U.; Shrock, Robert; /YITP, Stony Brook et al.
Object Type: Article
System: The UNT Digital Library
Dynamic Star Formation in the Massive DR21 Filament (open access)

Dynamic Star Formation in the Massive DR21 Filament

The formation of massive stars is a highly complex process in which it is unclear whether the star-forming gas is in global gravitational collapse or an equilibrium state supported by turbulence and/or magnetic fields. By studying one of the most massive and dense star-forming regions in the Galaxy at a distance of less than 3 kpc, i.e. the filament containing the well-known sources DR21 and DR21(OH), we attempt to obtain observational evidence to help us to discriminate between these two views. We use molecular line data from our {sup 13}CO 1 {yields} 0, CS 2 {yields} 1, and N{sub 2}H{sup +} 1 {yields} 0 survey of the Cygnus X region obtained with the FCRAO and CO, CS, HCO{sup +}, N{sub 2}H{sup +}, and H{sub 2}CO data obtained with the IRAM 30m telescope. We observe a complex velocity field and velocity dispersion in the DR21 filament in which regions of the highest column-density, i.e., dense cores, have a lower velocity dispersion than the surrounding gas and velocity gradients that are not (only) due to rotation. Infall signatures in optically thick line profiles of HCO{sup +} and {sup 12}CO are observed along and across the whole DR21 filament. By modelling the observed …
Date: August 25, 2010
Creator: Schneider, N.; Csengeri, T.; Bontemps, S.; Motte, F.; Simon, R.; Hennebelle, P. et al.
Object Type: Article
System: The UNT Digital Library
The Complete Four-Loop Four-Point Amplitude in N (open access)

The Complete Four-Loop Four-Point Amplitude in N

We present the complete four-loop four-point amplitude in N = 4 super-Yang-Mills theory, for a general gauge group and general D-dimensional covariant kinematics, and including all non-planar contributions. We use the method of maximal cuts - an efficient application of the unitarity method - to construct the result in terms of 50 four-loop integrals. We give graphical rules, valid in D-dimensions, for obtaining various non-planar contributions from previously-determined terms. We examine the ultraviolet behavior of the amplitude near D = 11/2. The non-planar terms are as well-behaved in the ultraviolet as the planar terms. However, in the color decomposition of the three- and four-loop amplitude for an SU(N{sub c}) gauge group, the coefficients of the double-trace terms are better behaved in the ultraviolet than are the single-trace terms. The results from this paper were an important step toward obtaining the corresponding amplitude in N = 8 supergravity, which confirmed the existence of cancellations beyond those needed for ultraviolet finiteness at four loops in four dimensions. Evaluation of the loop integrals near D = 4 would permit tests of recent conjectures and results concerning the infrared behavior of four-dimensional massless gauge theory.
Date: August 25, 2010
Creator: Bern, Z.; Carrasco, J.J.M.; /UCLA; Dixon, Lance J.; /CERN, /SLAC; Johansson, H. et al.
Object Type: Article
System: The UNT Digital Library
Information Basis for Developing Comprehensive Waste Management System-Us-Japan Joint Nuclear Energy Action Plan Waste Management Working Group Phase I Report. (open access)

Information Basis for Developing Comprehensive Waste Management System-Us-Japan Joint Nuclear Energy Action Plan Waste Management Working Group Phase I Report.

The activity of Phase I of the Waste Management Working Group under the United States - Japan Joint Nuclear Energy Action Plan started in 2007. The US-Japan JNEAP is a bilateral collaborative framework to support the global implementation of safe, secure, and sustainable, nuclear fuel cycles (referred to in this document as fuel cycles). The Waste Management Working Group was established by strong interest of both parties, which arise from the recognition that development and optimization of waste management and disposal system(s) are central issues of the present and future nuclear fuel cycles. This report summarizes the activity of the Waste Management Working Group that focused on consolidation of the existing technical basis between the U.S. and Japan and the joint development of a plan for future collaborative activities. Firstly, the political/regulatory frameworks related to nuclear fuel cycles in both countries were reviewed. The various advanced fuel cycle scenarios that have been considered in both countries were then surveyed and summarized. The working group established the working reference scenario for the future cooperative activity that corresponds to a fuel cycle scenario being considered both in Japan and the U.S. This working scenario involves transitioning from a once-through fuel cycle utilizing …
Date: May 25, 2010
Creator: Nutt, M. & Division, Nuclear Engineering
Object Type: Report
System: The UNT Digital Library
A Dual-Moded Cavity for RF Breakdown Studies (open access)

A Dual-Moded Cavity for RF Breakdown Studies

The phenomenon of rf breakdown presents a technological limitation in the application of high-gradient particle acceleration in normal conducting rf structures. Attempts to understand the onset of this phenomenon and to study its limits with different materials, cell shapes, and pulse widths has been driven in recent years by linear collider development. One question of interest is the role magnetic field plays relative to electric field. A design is presented for a single, nonaccelerating, rf cavity resonant in two modes, which, driven independently, allow the rf magnetic field to be increased on the region of highest electric field without affecting the latter. The design allows for the potential reuse of the cavity with different samples in the high-field region. High power data is not yet available.
Date: August 25, 2010
Creator: Nantista, Christopher; /SLAC; Adolphsen, Chris; /SLAC; Wang, Faya & /SLAC
Object Type: Article
System: The UNT Digital Library

Wind Power Answer In Times of Water Scarcity

Strategic energy planning is paramount during times of dramatic population growth, global warming, increasing energy demands, and concerns over energy security, food security, and economic development. Recent concerns over water scarcity have moved the energy-water issue to the forefront of energy options discussions. This presentation describes the current water challenges in the United States and presents a case for wind energy as one way to mitigate the problem of water scarcity in several U.S. regions while providing a clean and sustainable economic future for America.
Date: May 25, 2010
Creator: Flowers, L. & Reategui, S.
Object Type: Presentation
System: The UNT Digital Library