ARAC Modeling of the Algeciras, Spain Steel Mill CS-137 Release (open access)

ARAC Modeling of the Algeciras, Spain Steel Mill CS-137 Release

On 12 June 1998, the Atmospheric Release Advisory Capability (ARAC) learned from news reports about the accidental release of cesium-137 from a steel mill near Algeciras, Spain. We used the U.S. Navy Operational Global Atmospheric Prediction System (NOGAPS) gridded data for meteorological input into our diagnostic models. To better resolve near-release location and coastal meteorological conditions, we blended four days of WMO surface and upper air observations with the gridded data. Our calculations showed the plume initially traveled eastward over the Mediterranean Sea, turned northward into central Europe, and was split by the Alps. We determined the timing and amount of cesium released by fitting our modeled air concentrations to the available set of measurements. Accuracy statistics from a small set of ratios of measured to computed air concentrations paired in space and time were similar to those achieved from larger data sets in previous ARAC model evaluation studies on the continental scale.
Date: May 1, 1999
Creator: Vogt, P J; Pobanz, B M; Aluzzi, F J; Baskett, R L & Sullivan, T J
Object Type: Article
System: The UNT Digital Library
US-LHC Magnet Database and Conventions. (open access)

US-LHC Magnet Database and Conventions.

The US-LHC Magnet Database is designed for production-magnet quality assurance, field and alignment error impact analysis, cryostat assembly assistance, and ring installation assistance. The database consists of tables designed to store magnet field and alignment measurements data and quench data. This information will also be essential for future machine operations including local IR corrections.
Date: March 29, 1999
Creator: Wei, J.; McChesney, D.; Jain, A.; Peggs, S.; Pilat, F.; Bottura, L. et al.
Object Type: Article
System: The UNT Digital Library
Feedback Design Method Review and Comparison. (open access)

Feedback Design Method Review and Comparison.

Different methods for feedback designs are compared. These includes classical Proportional Integral Derivative (P. I. D.), state variable based methods like pole placement, Linear Quadratic Regulator (L. Q. R.), H-infinity and p-analysis. These methods are then applied for the design and analysis of the RHIC phase and radial loop, yielding a performance, stability and robustness comparison.
Date: March 29, 1999
Creator: Onillon, E.
Object Type: Article
System: The UNT Digital Library
Laser-induced back-ablation of aluminum thin films using picosecond laser pulses (open access)

Laser-induced back-ablation of aluminum thin films using picosecond laser pulses

Experiments were performed to understand laser-induced back-ablation of Al film targets with picosecond laser pulses. Al films deposited on the back surface of BK-7 substrates are ablated by picosecond laser pulses propagating into the Al film through the substrate. The ablated Al plume is transversely probed by a time-delayed, two-color sub-picoseond (500 fs) pulse, and this probe is then used to produce self-referencing interferograms and shadowgraphs of the Al plume in flight. Optical emission from the Al target due to LIBA is directed into a time-integrated grating spectrometer, and a time-integrating CCD camera records images of the Al plume emission. Ablated Al plumes are also redeposited on to receiving substrates. A post-experimental study of the Al target and recollected deposit characteristics was also done using optical microscopy, interferometry, and profilometry. In this high laser intensity regime, laser-induced substrate ionization and damage strongly limits transmitted laser fluence through the substrate above a threshold fluence. The threshold fluence for this ionization-based transmission limit in the substrate is dependent on the duration of the incident pulse. The substrate ionization can be used as a dynamic control of both transmitted spatial pulse profile and ablated Al plume shape. The efficiency of laser energy transfer …
Date: May 26, 1999
Creator: Bullock, A. B.
Object Type: Report
System: The UNT Digital Library
A compact proton linac for fast neutron cancer therapy (open access)

A compact proton linac for fast neutron cancer therapy

None
Date: January 1, 1999
Creator: Lennox, Arlene Judith; /Fermilab; Hamm, Robert W. & /AccSys Tech., Pleasanton
Object Type: Article
System: The UNT Digital Library
Environmentally Assisted Cracking in Light Water Reactors. Semiannual Report, July 1998-December 1998. (open access)

Environmentally Assisted Cracking in Light Water Reactors. Semiannual Report, July 1998-December 1998.

This report summarizes work performed by Argonne National Laboratory on fatigue and environmentally assisted cracking (EAC) in light water reactors from July 1998 to December 1998. Topics that have been investigated include (a) environmental effects on fatigue S-N behavior of primary pressure boundary materials, (b) irradiation-assisted stress corrosion cracking of austenitic stainless steels (SSs), and (c) EAC of Alloys 600 and 690. Fatigue tests have been conducted to determine the crack initiation and crack growth characteristics of austenitic SSs in LWR environments. Procedures are presented for incorporating the effects of reactor coolant environments on the fatigue life of pressure vessel and piping steels. Slow-strain-rate tensile tests and posttest fractographic analyses were conducted on several model SS alloys irradiated to {approx}0.3 and 0.9 x 10{sup 21} n {center_dot} cm{sup -2} (E > 1 MeV) in helium at 289 C in the Halden reactor. The results have been used to determine the influence of alloying and impurity elements on the susceptibility of these steels to irradiation-assisted stress corrosion cracking. Fracture toughness J-R curve tests were also conducted on two heats of Type 304 SS that were irradiated to {approx}0.3 x 10{sup 21} n {center_dot} cm{sup -2} in the Halden reactor. Crack-growth-rate tests …
Date: October 1, 1999
Creator: Chopra, O. K.; Chung, H. M.; Gruber, E. E.; Kassner, T. F.; Ruther, W. E.; Shack, W. J. et al.
Object Type: Report
System: The UNT Digital Library
Effects of a Lowered RHIC Injection Momentum (open access)

Effects of a Lowered RHIC Injection Momentum

N/A
Date: October 1, 1999
Creator: M., Brennan; Fischer, W.; Schultheiss, C. & Tsoupas, N.
Object Type: Report
System: The UNT Digital Library
High field solenoids for muon cooling (open access)

High field solenoids for muon cooling

The proposed cooling system for the muon collider will consist of a 200 meter long line of alternating field straight solenoids interspersed with bent solenoids. The muons are cooled in all directions using a 400 mm long section liquid hydrogen at high field. The muons are accelerated in the forward direction by about 900 mm long, 805 MHz RF cavities in a gradient field that goes from 6 T to -6 T in about 300 mm. The high field section in the channel starts out at an induction of about 2 T in the hydrogen. As the muons proceed down the cooling channel, the induction in the liquid hydrogen section increases to inductions as high as 30 T. The diameter of the liquid hydrogen section starts at 750 mm when the induction is 2 T. As the induction in the cooling section goes up, the diameter of the liquid hydrogen section decreases. When the high field induction is 30 T, the diameter of the liquid hydrogen section is about 80 mm. When the high field solenoid induction is below 8.5 T or 9T, niobium titanium coils are proposed for generating .the magnetic field. Above 8.5 T or 9 T to …
Date: September 8, 1999
Creator: Green, M. A.; Eyssa, Y.; Kenny, S.; Miller, J. R. & Prestemon, S.
Object Type: Article
System: The UNT Digital Library
Vector Potential and Stored Energy of a Quadrupole Magnet Array (open access)

Vector Potential and Stored Energy of a Quadrupole Magnet Array

The vector potential, magnetic field and stored energy of a quadrupole magnet array are derived. Each magnet within the array is a current sheet with a current density proportional to the azimuthal angle 2{theta} and the longitudinal periodicity (2m-1){pi}/L. Individual quadrupoles within the array are oriented in a way that maximizes the field gradient The array does not have to be of equal spacing and can be of a finite size, however when the array is equally spaced and is of infinite size the solution can be simplified. We note that whereas, in a single quadrupole magnet with a current density proportional to cos2{theta} the gradient is pure, such purity is not preserved in a quadrupole array.
Date: March 15, 1999
Creator: Caspi, S.
Object Type: Article
System: The UNT Digital Library
Annual Report 1998. Chemical Structure and Dynamics (open access)

Annual Report 1998. Chemical Structure and Dynamics

No abstract currently available for this report as the present time.
Date: May 10, 1999
Creator: Colson, Steven D. & McDowell, Robin S.
Object Type: Report
System: The UNT Digital Library
West Hackberry Tertiary Project (open access)

West Hackberry Tertiary Project

The West Hackberry Tertiary Project is a field test of the concept that air injection can be combined with the Double Displacement Process to produce a tertiary recovery process that is both low cost and economic at current oil prices. The Double Displacement Process is the gas displacement of a water invaded oil column for the purpose of recovering tertiary oil by gravity drainage. In reservoirs with pronounced bed dip such as those found in West Hackberry and other Gulf Coast salt dome fields, reservoir performance has shown that gravity drainage recoveries average 80% to 90% of the original oil in place while waterdrive recoveries average 50% to 60% of the original oil in place. The target for tertiary oil recovery in the Double Displacement Process is the incremental oil between the 50% to 60% waterdrive recoveries and the 80% to 90% gravity drainage recoveries. In previous field tests, the Double Displacement Process has proven successful in generating tertiary oil recovery. The use of air injection in this process combines the benefits of air's low cost and universal accessibility with the potential for accelerated oil recovery from the combustion process. If successful, this project will demonstrate that utilizing air injection …
Date: March 31, 1999
Creator: Haley, Kenneth; Gillham, Travis & Yannimaras, Demetrios
Object Type: Report
System: The UNT Digital Library
Use of fish community data to evaluate restoration success of a riparian stream. (open access)

Use of fish community data to evaluate restoration success of a riparian stream.

Abstract From 1985 to 1988, stream and riparian habitats in Pen branch and Four Mile branch began recovering from deforestation caused by the previous release of hot water from nuclear reactors. The Pen branch corridor was replanted with wetland trees in 1995 to expedite recovery and restore the Pen branch ecosystem. Pen branch, Four Mile branch, and two relatively undisturbed streams were electrofished in 1995:1996 to determine how fish assemblages differed between the previously disturbed and undisturbed streams and whether such difference could be used to measure restoration success in Pen branch. Fish assemblages were analyzed using nonparametric multivariate statistical methods and the index of biotic integrity (IBI), a bioassessment method based on measurement of ecologically sensitive characteristics of fish assemblages. Many aspects of fish assemblage structure (e.g. species richness, disease incidence, taxonomic composition at the family level) did not differ between disturbed and undisturbed streams; however, the disturbed streams were characterized by higher densities of a number of species. These differences were successfully detected with the multivariate statistical methods; whereas, the IBI did not differ between most recovering and undisturbed sampling sites. Because fish assemblages are strongly influenced by instream habitat, and because instream habitat is strongly influenced by …
Date: September 1, 1999
Creator: Paller, Michael, H.; Reichert, Marcel, J.M.; Dean, John, M. & Seigle, John, C.
Object Type: Article
System: The UNT Digital Library
A geometric level set model for ultrasounds analysis (open access)

A geometric level set model for ultrasounds analysis

We propose a partial differential equation (PDE) for filtering and segmentation of echocardiographic images based on a geometric-driven scheme. The method allows edge-preserving image smoothing and a semi-automatic segmentation of the heart chambers, that regularizes the shapes and improves edge fidelity especially in presence of distinct gaps in the edge map as is common in ultrasound imagery. A numerical scheme for solving the proposed PDE is borrowed from level set methods. Results on human in vivo acquired 2D, 2D+time,3D, 3D+time echocardiographic images are shown.
Date: October 1, 1999
Creator: Sarti, A. & Malladi, R.
Object Type: Article
System: The UNT Digital Library
Reducing Mortality from Terrorist Releases of Chemical and Biological Agents: I. Filtration for Ventilation Systems in Commercial Building (open access)

Reducing Mortality from Terrorist Releases of Chemical and Biological Agents: I. Filtration for Ventilation Systems in Commercial Building

There is growing concern about potential terrorist attacks involving releases of chemical and/or biological (CB) agents, such as sarin or anthrax, in and around buildings. For an external release, the CB agent can enter the building through the air intakes of a building's mechanical ventilation system and by infiltration through the building envelope. For an interior release in a single room, the mechanical ventilation system, which often recirculates some fraction of the air within a building, may distribute the released CB agent throughout the building. For both cases, installing building systems that remove chemical and biological agents may be the most effective way to protect building occupants. Filtration systems installed in the heating, ventilating and air-conditioning (HVAC) systems of buildings can significantly reduce exposures of building occupants in the event of a release, whether the release is outdoors or indoors. Reduced exposures can reduce the number of deaths from a terrorist attack. The purpose of this report is to provide information and examples of the design of filtration systems to help building engineers retrofit HVAC systems. The report also provides background information on the physical nature of CB agents and brief overviews of the basic principles of particle and vapor …
Date: September 1, 1999
Creator: Thatcher, Tracy L. & Daisey, Joan M.
Object Type: Report
System: The UNT Digital Library
Fabrication and Test Results of a Nb3Sn Superconducting Racetrack Dipole Magnet (open access)

Fabrication and Test Results of a Nb3Sn Superconducting Racetrack Dipole Magnet

A 'proof-of-principle' Nb{sub 3}Sn superconducting dual-bore dipole magnet was built from racetrack coils, as a first step in a program to develop an economical, 15 Tesla, accelerator-quality magnet. The mechanical design and magnet fabrication procedures are discussed. No training was required to achieve temperature-dependent plateau currents, despite several thermal cycles that involved partial magnet disassembly and substantial pre-load variations. Subsequent magnets are expected to approach 15 Tesla with substantially improved conductor.
Date: March 22, 1999
Creator: Chow, K.; Dietderich, D. R.; Gourlay, S. A.; Gupta, R.; Harnden, W.; Lietzke, A. F. et al.
Object Type: Article
System: The UNT Digital Library
Superconducting magnets for muon capture and phase rotation (open access)

Superconducting magnets for muon capture and phase rotation

There are two key systems that must operate efficiently, in order for a muon collider to be a viable option for high energy physics. These systems are the muon production and collection system and the muon cooling system. Both systems require the use of high field superconducting solenoid magnets. This paper describes the supcrconducting solenoid system used for the capture and phase rotation of the pions that are produced on a target in a high intensity proton beam.
Date: July 26, 1999
Creator: Green, M.A. & Weggel, R.J.
Object Type: Article
System: The UNT Digital Library
On the Possibility of Observing Transverse Echos in RHIC (open access)

On the Possibility of Observing Transverse Echos in RHIC

N/A
Date: October 1, 1999
Creator: O., Bruning; Fisher, W. & Parker, B.
Object Type: Report
System: The UNT Digital Library
A Four Cell Lattice for the UCLA Compact Light Source Synchrotron (open access)

A Four Cell Lattice for the UCLA Compact Light Source Synchrotron

The 1.5 GeV compact light source UCS proposed for UCLA must fit into a shielded vault that is 9.144 meters (30 feet) wide. In order for the machine to fit into the allowable space, the ring circumference must be reduced 36 meters, the circumference of the six cell lattice, to something like 26 or 27 meters. The four cell lattice described in this report has a ring circumference of 27.0 meters.
Date: March 12, 1999
Creator: Garren, A.A. & Green, M.A.
Object Type: Article
System: The UNT Digital Library
Application for the Risk-Based Storage of PCB Reme (open access)

Application for the Risk-Based Storage of PCB Reme

This assessment discusses the PCB hazards present at the Idaho National Engineering and Environmental Laboratory (INEEL) Radioactive Waste Management Complex (RWMC) Transuranic Storage Area Retrieval Enclosure (TSA-RE); the various controls; natural, engineered and administrative that are in place to manage these hazards and minimize any potential risks; and the monitoring and surveillance activities that assure the aforementioned actions are indeed protective of the environment and the public and the worked. This assessment covers only the interim storage of polychlorinated biphenyls (PCBs).
Date: November 1, 1999
Creator: Becker, William Joseph
Object Type: Report
System: The UNT Digital Library
Tests of a GM Cryocooler and high Tc leads for use on the ALS superbend magnets (open access)

Tests of a GM Cryocooler and high Tc leads for use on the ALS superbend magnets

A 1.5 W (at the second stage) Gifford McMahon (GM) cryocooler was selected for cooling the superconducting SuperBend dipoles for the Advanced Light Source (ALS) at Berkeley. A GM cryocooler is a reasonable choice if conduction cooled leads are used to provide current to the superconducting magnet. The expected parasitic heat leaks are expected to range from 0.1 to 0.5 W at 4.2 K depending on the temperature of the shield and the cold mass support intercepts. Heat flow to 4 K down the SuperBend 350 A high Tc superconducting leads is expected to vary from 0.11 to 0.35 W depending on the intercept temperature and the current in the leads. The high Tc leads are designed to carry 350 A without significant resistive heating when the upper end of the lead is at 80 K. The 1.5 W cryocooler is expected to provide 45 to 50 W of refrigeration at the first stage at 50 K. The parasitic beat load into the first stage of the cryocooler will be about 8 W. The heat flow from 300 K down the upper copper leads is expected to be around 30 W. The cryocooler and high Tc lead test will measure …
Date: July 9, 1999
Creator: Zbasnik, J.; Green, M. A.; Hoyer, E. H.; Taylor, C. E.; Chen, J. Y. & Wang, S. T.
Object Type: Article
System: The UNT Digital Library
Refrigeration options for the Advanced Light Source Superbend Dipole Magnets (open access)

Refrigeration options for the Advanced Light Source Superbend Dipole Magnets

The 1.9 GeV Advance Light Source (ALS) at the Lawrence Berkeley National Laboratory (LBNL) produces photons with a critical energy of about 3.1 kev at each of its thirty-six 1.3 T gradient bending magnets. It is proposed that at three locations around the ring the conventional gradient bending magnets be replaced with superconducting bending magnets with a maximum field of 5.6 T. At the point where the photons are extracted, their critical energy will be about 12 keV. In the beam lines where the SuperBend superconducting magnets are installed, the X ray brightness at 20 keV will be increased over two orders of magnitude. This report describes three different refrigeration options for cooling the three SuperBend dipoles. The cooling options include: (1) liquid helium and liquid nitrogen cryogen cooling using stored liquids, (2) a central helium refrigerator (capacity 70 to 100 W) cooling all of the SuperBend magnets, (3) a Gifford McMahon (GM) cryocooler on each of the dipoles. This paper describes the technical and economic reasons for selecting a small GM cryocooler as the method for cooling the SuperBend dipoles on the LBNL Advanced Light Source.
Date: July 9, 1999
Creator: Green, M. A.; Hoyer, E. H.; Schlueter, R. D.; Taylor, C. E.; Zbasnik, J. & Wang, S. T.
Object Type: Article
System: The UNT Digital Library
The design and construction of a gradient solenoid for the high powered RF cavity experiment for the muon collider (open access)

The design and construction of a gradient solenoid for the high powered RF cavity experiment for the muon collider

This report describes the construction and test of a split solenoid that has a warm bore of 440 mm and a cryostat length of 1088 mm. (A 750 mm section contains the magnetic field.) When the coils are hooked so the fields are additive, the central induction is 5.0 T at its design current. When the coils are hooked so that the fields are in opposition, the induction at the center of the solenoid is zero and the peak induction on the solenoid axis is {+-}3.7 T. The on-axis induction gradient is 25 T per meter when the coils are hooked in opposition. When the coils are operated at their design currents in opposition, the force pushing the two coils apart is about 3 MN. The force pushing the coils apart is carried by the aluminum coil mandrel and a solid aluminum sheath outside of the superconducting winding. The coil was wound as a wet lay-up coil using alumina filled epoxy (Stycast). A layer of hard aluminum wire wound on the outside of the superconducting coil carries some of the hoop forces and limits the strain so that training does not occur. At design current, at both polarities, the peak …
Date: September 5, 1999
Creator: Green, M. A.; Chen, J. Y. & Wang, S. T.
Object Type: Article
System: The UNT Digital Library
Transferring Polarized Proton Beam from AGS to RHIC at Energies below the Spin Resonance G g=36+ny (open access)

Transferring Polarized Proton Beam from AGS to RHIC at Energies below the Spin Resonance G g=36+ny

N/A
Date: October 1, 1999
Creator: N., Tsoupas; Bai, M.; Huang, H. & Roser, T.
Object Type: Report
System: The UNT Digital Library
RF Capture and Acceleration of Gold Ions in Booster (open access)

RF Capture and Acceleration of Gold Ions in Booster

N/A
Date: November 1, 1999
Creator: Gardner, C. J.
Object Type: Report
System: The UNT Digital Library