Resource Type

Managing Carbon Regulatory Risk in Utility Resource Planning:Current Practices in the Western United States (open access)

Managing Carbon Regulatory Risk in Utility Resource Planning:Current Practices in the Western United States

Concerns about global climate change have substantially increased the likelihood that future policy will seek to minimize carbon dioxide emissions. Assuch, even today, electric utilities are making resource planning and investment decisions that consider the possible implications of these future carbon regulations. In this article, we examine the manner in which utilities assess the financial risks associated with future carbon regulations within their long-term resource plans. We base our analysis on a review of the most recent resource plans filed by fifteen electric utilities in the Western United States. Virtually all of these utilities made some effort to quantitatively evaluate the potential cost of future carbon regulations when analyzing alternate supply- and demand-side resource options for meeting customer load. Even without Federal climate regulation in the U.S., the prospect of that regulation is already having an impact on utility decision-making and resource choices. That said, the methods and assumptions used by utilities to analyze carbon regulatory risk, and the impact of that analysis on their choice of a particular resource strategy, vary considerably, revealing a number of opportunities for analytic improvement. Though our review focuses on a subset of U.S. electric utilities, this work holds implications for all electric utilities …
Date: May 16, 2008
Creator: Barbose, Galen; Wiser, Ryan; Phadke, Amol & Goldman, Charles
System: The UNT Digital Library
Correlation between Strand Stability and Magnet Performance (open access)

Correlation between Strand Stability and Magnet Performance

Magnet programs at BNL, LBNL and FNAL have observed instabilities in high J{sub c} Nb{sub 3}Sn strands and magnets made from these strands. This paper correlates the strand stability determined from a short sample-strand test to the observed magnet performance. It has been observed that strands that carry high currents at high fields (greater than 10T) cannot sustain these same currents at low fields (1-3T) when the sample current is fixed and the magnetic field is ramped. This suggests that the present generation of strand is susceptible to flux jumps (FJ). To prevent flux jumps from limiting stand performance, one must accommodate the energy released during a flux jump. To better understand FJ this work has focused on wire with a given sub-element diameter and shows that one can significantly improve stability by increasing the copper conductivity (higher residual resistivity ratio, RRR, of the Cu). This increased stability significantly improves the conductor performance and permits it to carry more current.
Date: April 16, 2005
Creator: Dietderich, Daniel R.; Bartlett, Scott E.; Caspi, Shlomo; Ferracin, Paolo; G ourlay, Stephen A.; Higley, Hugh C. et al.
System: The UNT Digital Library
Performances of Induction System for Nanosecond Mode Operation (open access)

Performances of Induction System for Nanosecond Mode Operation

An induction system comprises an array of single turn pulse transformers. Ferromagnetic cores of transformers are toroids that are stacked along the longitudinal core axis. Another name for this array is a fraction transformer or an adder. The primary and secondary windings of such a design have one turn. The step up mode is based on the number of primary pulse sources. The secondary windings are connected in series. Performances of such a system for the nanosecond range mode operation are different in comparison to the performances of traditional multi-turn pulse transformers, which are working on a 100+ nanosecond mode operation. In this paper, the author discusses which aspects are necessary to take into account for the high power nanosecond fractional transformer designs. The engineering method of the nanosecond induction system design is presented.
Date: May 16, 2006
Creator: Krasnykh, Anatoly
System: The UNT Digital Library
Geometrical Effects in Plasma Stability and Dynamics of Coherent Structures in the Divertor (open access)

Geometrical Effects in Plasma Stability and Dynamics of Coherent Structures in the Divertor

Plasma dynamics in the divertor region is strongly affected by a variety of phenomena associated with the magnetic field geometry and the shape of the divertor plates. One of the most universal effects is the squeezing of a normal cross-section of a thin magnetic flux-tube on its way from the divertor plate to the main SOL. It leads to decoupling of the most unstable perturbations in the divertor legs from those in the main SOL. For perturbations on either side of the X-point, this effect can be cast as a boundary condition at some 'control surface' situated near the X-point. We discuss several boundary conditions proposed thus far and assess the influence of the magnetic field geometry on them. Another set of geometrical effects is related to the transformation of a flux-tube that occurs when it is displaced in such a way that its central magnetic field line coincides with some other field line, and the magnetic field is not perturbed. These flute-like displacements are of a particular interest for the low-beta edge plasmas. It turns out that this transformation may also lead to a considerable deformation of a flux-tube cross-section; in addition, the distance between plasma particles occupying the …
Date: May 16, 2007
Creator: Ryutov, D. D. & Cohen, R. H.
System: The UNT Digital Library
A Possible Connection Between Dark Energy And the Hierarchy (open access)

A Possible Connection Between Dark Energy And the Hierarchy

Recently it was suggested that the dark energy maybe related to the well-known hierarchy between the Planck scale ({approx} 10{sup 19} GeV) and the TeV scale. The same brane-world setup to address this hierarchy problem may also in principle address the smallness problem of dark energy. Specifically, the Planck-SM hierarchy ratio was viewed as a quantum gravity-related, dimensionless fine structure constant where various physical energy scales in the system are associated with the Planck mass through different powers of the 'gravity fine structure constant'. In this paper we provide a toy model based on the Randall-Sundrum geometry where SUSY-breaking is induced by the coupling between a SUSY-breaking Higgs field on the brane and the KK gravitinos. We show that the associated Casimir energy density indeed conforms with the dark energy scale.
Date: November 16, 2007
Creator: Chen, Pisin; /SLAC /KIPAC, Menlo Park; Gu, Je-An & /NCTS, Hsinchu
System: The UNT Digital Library
Validation of DNA probes for molecular cytogenetics by mapping onto immobilized circular DNA (open access)

Validation of DNA probes for molecular cytogenetics by mapping onto immobilized circular DNA

Fluorescence in situ hybridization (FISH) is a sensitive and rapid procedure to detect gene rearrangements in tumor cells using non-isotopically labeled DNA probes. Large insert recombinant DNA clones such as bacterial artificial chromosome (BAC) or P1/PAC clones have established themselves in recent years as preferred starting material for probe preparations due to their low rates of chimerism and ease of use. However, when developing probes for the quantitative analysis of rearrangements involving genomic intervals of less than 100kb, careful probe selection and characterization are of paramount importance. We describe a sensitive approach to quality control probe clones suspected of carrying deletions or for measuring clone overlap with near kilobase resolution. The method takes advantage of the fact that P1/PAC/BAC's can be isolated as circular DNA molecules, stretched out on glass slides and fine-mapped by multicolor hybridization with smaller probe molecules. Two examples demonstrate the application of this technique: mapping of a gene-specific {approx}6kb plasmid onto an unusually small, {approx}55kb circular P1 molecule and the determination of the extent of overlap between P1 molecules homologous to the human NF-?B2 locus. The relatively simple method presented here does not require specialized equipment and may thus find widespread applications in DNA probe preparation …
Date: December 16, 2008
Creator: Greulich-Bode, Karin; Wang, Mei; Rhein, Andreas; Weier, Jingly & Weier, Heinz-Ulli
System: The UNT Digital Library
Direct drive heavy-ion-beam inertial fusion at high coupling efficiency (open access)

Direct drive heavy-ion-beam inertial fusion at high coupling efficiency

Issues with coupling efficiency, beam illumination symmetry, and Rayleigh-Taylor instability are discussed for spherical heavy-ion-beam-driven targets with and without hohlraums. Efficient coupling of heavy-ion beams to compress direct-drive inertial fusion targets without hohlraums is found to require ion range increasing several-fold during the drive pulse. One-dimensional implosion calculations using the LASNEX inertial confinement fusion target physics code shows the ion range increasing fourfold during the drive pulse to keep ion energy deposition following closely behind the imploding ablation front, resulting in high coupling efficiencies (shell kinetic energy/incident beam energy of 16% to 18%). Ways to increase beam ion range while mitigating Rayleigh-Taylor instabilities are discussed for future work.
Date: May 16, 2008
Creator: Logan, B. G.; Perkins, L. J. & Barnard, J. J.
System: The UNT Digital Library
Energy Efficiency Standards and Labels in North America: Opportunities for Harmonization (open access)

Energy Efficiency Standards and Labels in North America: Opportunities for Harmonization

To support the North American Energy Working Group's Expert Group on Energy Efficiency (NAEWG-EE), USDOE commissioned the Collaborative Labeling and Appliance Standards Program (CLASP) to prepare a resource document comparing current standards, labels, and test procedure regulations in Canada, Mexico, and the United States. The resulting document reached the following conclusions: Out of 24 energy-using products for which at least one of the three countries has energy efficiency regulations, three products -- refrigerators/freezers, split system central air conditioners, and room air conditioners -- have similar or identical minimum energy performance standards (MEPS) in the three countries. These same three products, as well as three-phase motors, have similar or identical test procedures throughout the region. There are 10 products with different MEPS and test procedures, but which have the short-term potential to develop common test procedures, MEPS, and/or labels. Three other noteworthy areas where possible energy efficiency initiatives have potential for harmonization are standby losses, uniform endorsement labels, and a new standard or label on windows. This paper explains these conclusions and presents the underlying comparative data.
Date: May 16, 2002
Creator: Vanwiemcgrory, Laura; Wiel, Stephen; Van Wie McGrory, Laura & Harrington, Lloyd
System: The UNT Digital Library
Analytical analysis of longitudinal space charge effects for a bunched beam with radial dependence (open access)

Analytical analysis of longitudinal space charge effects for a bunched beam with radial dependence

The longitudinal space-charge (LSC) force can be a major cause of the microbunching instability in the linac for an x-ray free-electron laser. In this paper, the LSC-induced beam modulation is studied using an integral equation approach that takes into account the transverse (radial) variation of the LSC field for both the coasting-beam limit and a bunched beam. Variation of the beam energy and the transverse beam size is also incorporated. We discuss the validity of this approach and compare it with other analytical analyses as well as numerical simulations.
Date: June 16, 2008
Creator: Wu, Juhao; Huang, Zhirong & Emma, Paul
System: The UNT Digital Library
AUTOMATING GROUNDWATER SAMPLING AT HANFORD (open access)

AUTOMATING GROUNDWATER SAMPLING AT HANFORD

Until this past October, Fluor Hanford managed Hanford's integrated groundwater program for the U.S. Department of Energy (DOE). With the new contract awards at the Site, however, the CH2M HILL Plateau Remediation Company (CHPRC) has assumed responsibility for the groundwater-monitoring programs at the 586-square-mile reservation in southeastern Washington State. These programs are regulated by the Resource Conservation and Recovery Act (RCRA) and the Comprehensive Environmental Response Compensation and Liability Act (CERCLA). The purpose of monitoring is to track existing groundwater contamination from past practices, as well as other potential contamination that might originate from RCRA treatment, storage, and disposal (TSD) facilities. An integral part of the groundwater-monitoring program involves taking samples of the groundwater and measuring the water levels in wells scattered across the site. More than 1,200 wells are sampled each year. Historically, field personnel or 'samplers' have been issued pre-printed forms that have information about the well(s) for a particular sampling evolution. This information is taken from the Hanford Well Information System (HWIS) and the Hanford Environmental Information System (HEIS)--official electronic databases. The samplers used these hardcopy forms to document the groundwater samples and well water-levels. After recording the entries in the field, the samplers turned the forms …
Date: January 16, 2009
Creator: CW, CONNELL; RD, HILDEBRAND; SF, CONLEY & DE, CUNNINGHAM
System: The UNT Digital Library
Post-Treatment Hemodynamics of a Basilar Aneurysm and Bifurcation (open access)

Post-Treatment Hemodynamics of a Basilar Aneurysm and Bifurcation

Aneurysm re-growth and rupture can sometimes unexpectedly occur following treatment procedures that were initially considered to be successful at the time of treatment and post-operative angiography. In some cases, this can be attributed to surgical clip slippage or endovascular coil compaction. However, there are other cases in which the treatment devices function properly. In these instances, the subsequent complications are due to other factors, perhaps one of which is the post-treatment hemodynamic stress. To investigate whether or not a treatment procedure can subject the parent artery to harmful hemodynamic stresses, computational fluid dynamics simulations are performed on a patient-specific basilar aneurysm and bifurcation before and after a virtual endovascular treatment. The simulations demonstrate that the treatment procedure produces a substantial increase in the wall shear stress. Analysis of the post-treatment flow field indicates that the increase in wall shear stress is due to the impingement of the basilar artery flow upon the aneurysm filling material and to the close proximity of a vortex tube to the artery wall. Calculation of the time-averaged wall shear stress shows that there is a region of the artery exposed to a level of wall shear stress that can cause severe damage to endothelial cells. …
Date: January 16, 2008
Creator: Ortega, J; Hartman, J; Rodriguez, J & Maitland, D
System: The UNT Digital Library
Development of pseudo-random binary gratings and arrays for calibration of surface profile metrology tools (open access)

Development of pseudo-random binary gratings and arrays for calibration of surface profile metrology tools

Optical Metrology tools, especially for short wavelength (EUV and X-Ray), must cover a wide range of spatial frequencies from the very low, which affects figure, to the important mid-spatial frequencies and the high spatial frequency range, which produces undesirable flair. A major difficulty in using surface profilometers arises due to the unknown Modulation Transfer Function (MTF) of the instruments. Therefore, accurate calibration of profilometers, the understanding of their MTF limitations, and cross calibration between tools represents a considerable challenge for quantitative optical metrology. In previous work the instrumental MTF of a surface profiler was precisely measured using reference test surfaces based on binary pseudo-random (BPR) gratings. Here, they present results of fabricating and using two-dimensional (2D) BPR arrays that allow for a direct 2D calibration of the instrumental MTF. BPR sequences are widely used in engineering and communication applications such as Global Position System, and wireless communication protocol. The ideal BPR pattern has a flat 'white noise' response over the entire range of spatial frequencies of interest. The BPR array used here is based on the Uniformly Redundant Array prescription initially used for x-ray and gamma ray astronomy applications. The URA's superior imaging capability originates from the fact that its …
Date: January 16, 2009
Creator: Barber, Samuel K.; Soldate, Paul; Anderson, Erik; Cambie, Rosanna; McKinney, Wayne R.; Takacs, Peter Z. et al.
System: The UNT Digital Library
CURRENT PROGRESS AND FUTURE PLANS FOR THE DOE OFFICE OF ENVIRONMENTAL MANAGEMENT INTERNATIONAL PROGRAM (open access)

CURRENT PROGRESS AND FUTURE PLANS FOR THE DOE OFFICE OF ENVIRONMENTAL MANAGEMENT INTERNATIONAL PROGRAM

The U.S. Department of Energy's (DOE) Office of Environmental Management (EM) has collaborated with various international institutes for many years on radioactive waste management challenges of mutual concern. Currently, DOE-EM is performing collaborative work with researchers at the Khlopin Radium Institute and the SIA Radon Institute in Russia and the Ukraine's International Radioecology Laboratory to explore issues related to high-level waste and to investigate experience and technologies that could support DOE-EM site cleanup needs. Specific initiatives include: (1) Application of the Cold Crucible Induction Heated Melter to DOE Wastes--SIA Radon and Savannah River National Laboratory; (2) Improved Solubility and Retention of Troublesome Components in SRS and Hanford Waste Glasses--Khlopin Radium Institute, Pacific Northwest National Laboratory and Savannah River National Laboratory; and (3) Long-term Impacts from Radiation/Contamination within the Chernobyl Exclusion Zone--International Radioecology Laboratory and Savannah River National Laboratory. This paper provides an overview of the status of the current International Program task activities. The paper will also provide insight into the future direction for the program. Specific ties to the current DOE-EM technology development multi-year planning effort will be highlighted as well as opportunities for future international collaborations.
Date: November 16, 2007
Creator: Marra, J; Kurt D Gerdes, K; David Peeler, D; John Harbour, J & Kevin Fox, K
System: The UNT Digital Library
COMPASS, the COMmunity Petascale project for Accelerator Science and Simulation, a board computational accelerator physics initiative (open access)

COMPASS, the COMmunity Petascale project for Accelerator Science and Simulation, a board computational accelerator physics initiative

Accelerators are the largest and most costly scientific instruments of the Department of Energy, with uses across a broad range of science, including colliders for particle physics and nuclear science and light sources and neutron sources for materials studies. COMPASS, the Community Petascale Project for Accelerator Science and Simulation, is a broad, four-office (HEP, NP, BES, ASCR) effort to develop computational tools for the prediction and performance enhancement of accelerators. The tools being developed can be used to predict the dynamics of beams in the presence of optical elements and space charge forces, the calculation of electromagnetic modes and wake fields of cavities, the cooling induced by comoving beams, and the acceleration of beams by intense fields in plasmas generated by beams or lasers. In SciDAC-1, the computational tools had multiple successes in predicting the dynamics of beams and beam generation. In SciDAC-2 these tools will be petascale enabled to allow the inclusion of an unprecedented level of physics for detailed prediction.
Date: July 16, 2007
Creator: Cary, J. R.; Spentzouris, P.; Amundson, J.; McInnes, L.; Borland, M.; Mustapha, B. et al.
System: The UNT Digital Library
Activity Coefficient Derivatives of Ternary Systems Based on Scatchard's Neutral Electrolyte description (open access)

Activity Coefficient Derivatives of Ternary Systems Based on Scatchard's Neutral Electrolyte description

Activity coefficient derivatives with respect to molality are presented for the Scatchard Neutral Electrolyte description of a ternary common-ion electrolyte system. These quantities are needed for the calculation of 'diffusion Onsager coefficients' and in turn for tests of the Onsager Reciprocal Relations in diffusion. The usually-omitted b{sub 23} term is included. The direct SNE binary approximations and a further approximation are discussed. Binary evaluation strategies other than constant ionic strength are considered.
Date: May 16, 2007
Creator: Miller, D. G.
System: The UNT Digital Library
ESTABLISHING FINAL END STATE FOR A RETIRED NUCLEAR WEAPONS PRODUCTION REACTOR; COLLABORATION BETWEEN STAKEHOLDERS, REGULATORS AND THE FEDERAL GOVERNMENT (open access)

ESTABLISHING FINAL END STATE FOR A RETIRED NUCLEAR WEAPONS PRODUCTION REACTOR; COLLABORATION BETWEEN STAKEHOLDERS, REGULATORS AND THE FEDERAL GOVERNMENT

The Savannah River Site (SRS) is a 310-square-mile United States Department of Energy nuclear facility located along the Savannah River (SRS) near Aiken, South Carolina. Nuclear weapons material production began in the early 1950s, utilizing five production reactors. In the early 1990s all SRS production reactor operations were terminated. The first reactor closure end state declaration was recently institutionalized in a Comprehensive Environmental Response and Compensation and Liability Act (CERCLA) Early Action Record of Decision. The decision for the final closure of the 318,000 square foot 105-P Reactor was determined to be in situ decommissioning (ISD). ISD is an acceptable and cost effective alternative to off-site disposal for the reactor building, which will allow for consolidation of remedial action wastes generated from other cleanup activities within the P Area. ISD is considered protective by the regulators, U. S. Environmental Protection Agency (US EPA) and the South Carolina Department of Health and Environmental Control (SCDHEC), public and stakeholders as waste materials are stabilized/immobilized, and radioactivity is allowed to naturally decay, thus preventing future exposure to the environment. Stakeholder buy-in was critical in the upfront planning in order to achieve this monumental final decision. Numerous public meetings and workshops were held in …
Date: January 16, 2009
Creator: Bergren, C
System: The UNT Digital Library
Data Analysis in the Twenty-First Century (open access)

Data Analysis in the Twenty-First Century

The 21st Century is characterized by complex multidisciplinary problems accompanied by massive datasets. 'We are drowning in data, but starving for knowledge', as the volumes of many commercial, industrial and scientific datasets have exceeded the terabyte range and are approaching petabytes and beyond. Statistical methodology has long been employed to find useful and usable information in data. More recently, data mining has harnessed the power of computer technology to find useful and usable patterns in such massive datasets. Although several data mining journals have joined the established statistical journals, no single journal provides an integrated treatment of statistical analysis methodology and data mining technology, particularly when applied to the solution of practical problems. This absence and the needs expressed above motivated the inauguration of John Wiley's new Journal on Statistical Analysis and Data Mining. The goals of this interdisciplinary journal are to encourage collaborations across disciplines, communication of data mining and statistical techniques to both novices and experts involved in the analysis of data from practical problems, and a principled and productive evaluation of analyses and solutions. The journal specifically encourages submission of works that have statistical rigor in the analysis of data, incorporate the most appropriate algorithms from data …
Date: August 16, 2007
Creator: Goodman, A; Kamath, C & Kumar, V
System: The UNT Digital Library
Evaluation of the effects of various culture condition on Cr (VI) reduction by Shewanella oneidensis MR-1 in a novel high-throughputmini-bioreactor (open access)

Evaluation of the effects of various culture condition on Cr (VI) reduction by Shewanella oneidensis MR-1 in a novel high-throughputmini-bioreactor

The growth and Cr(VI) reduction by Shewanella oneidensisMR-1 was examined using a mini-bioreactor system that independentlymonitors and controls pH, dissolved oxygen, and temperature for each ofits 24, 10-mL reactors. Independent monitoring and control of eachreactor in the cassette allows the exploration of a matrix ofenvironmental conditions known to influence S. oneidensis chromiumreduction. S. oneidensis MR-1 grew in minimal medium without amino acidor vitamin supplementation under aerobic conditions but required serineand glycine supplementation under anaerobic conditions. Growth wasinhibited by dissolved oxygen concentrations>80 percent. Lactatetransformation to acetate was enhanced by low concentration of dissolvedoxygen during the logarithmic growth phase. Between 11 and 35oC, thegrowth rate obeyed the Arrhenius reaction rate-temperature relationship,with a maximum growth rate occurring at 35oC. S. oneidensis MR-1 was ableto grow over a wide range of pH (6-9). At neutral pH and temperaturesranging from 30-35oC, S. oneidensis MR-1 reduced 100 mu M Cr(VI) toCr(III) within 20 minutes in the exponential growth phase, and the growthrate was not affected by the addition of chromate; it reduced chromateeven faster at temperatures between 35 and 39oC. At low temperatures(<25oC), acidic (pH<6.5), or alkaline (pH>8.5) conditions, 100mu M Cr(VI) strongly inhibited growth and chromate reduction. Themini-bioreactor system enabled the rapid determination of theseparameters …
Date: March 16, 2006
Creator: Tang, Yinjie J.; Laidlaw, David; Gani, Kishen & Keasling, Jay D.
System: The UNT Digital Library
On cylindrically converging shock waves shaped by obstacles (open access)

On cylindrically converging shock waves shaped by obstacles

Motivated by recent experiments, numerical simulations were performed of cylindrically converging shock waves. The converging shocks impinged upon a set of zero to sixteen regularly space obstacles. For more than two obstacles the resulting diffracted shock fronts formed polygonal shaped patterns near the point of focus. The maximum pressure and temperature as a function of number of obstacles were studied. The self-similar behavior of cylindrical, triangular and square-shaped shocks were also investigated.
Date: July 16, 2007
Creator: Eliasson, V; Henshaw, W D & Appelo, D
System: The UNT Digital Library
UITI2007-University Information Technical Interchange Review Meeting (open access)

UITI2007-University Information Technical Interchange Review Meeting

None
Date: January 16, 2008
Creator: Franques, V.; Williams, R.; Schubert, S.; Bloch, J.; Ostrogorsky, A.; Burger, A. et al.
System: The UNT Digital Library
Multithreading for Synchronization Tolerance in MatrixFactorization (open access)

Multithreading for Synchronization Tolerance in MatrixFactorization

Physical constraints such as power, leakage and pin bandwidth are currently driving the HPC industry to produce systems with unprecedented levels of concurrency. In these parallel systems, synchronization and memory operations are becoming considerably more expensive than before. In this work we study parallel matrix factorization codes and conclude that they need to be re-engineered to avoid unnecessary (and expensive) synchronization. We propose the use of multithreading combined with intelligent schedulers and implement representative algorithms in this style. Our results indicate that this strategy can significantly outperform traditional codes.
Date: July 16, 2007
Creator: Buttari, Alfredo; Dongarra, Jack; Husbands, Parry; Kurzak, Jakub & Yelick, Katherine
System: The UNT Digital Library
Simulation of beams or plasmas crossing at relaticisticvelocity (open access)

Simulation of beams or plasmas crossing at relaticisticvelocity

None
Date: November 16, 2007
Creator: Vay, J. L.
System: The UNT Digital Library
Application of Bomb Radiocarbon Chronologies to Shortfin Mako (Isurus oxyrinchus) (open access)

Application of Bomb Radiocarbon Chronologies to Shortfin Mako (Isurus oxyrinchus)

There is an ongoing disagreement regarding the aging of the shortfin mako due to a difference of interpretation in the periodic deposition of vertebral growth band pairs, especially for the larger size classes. Using analysis of length-month information, tagging data, and length-frequency analysis, concluded that two band pairs were formed in the vertebral centrum every year (biannual band-pair interpretation). Cailliet et al. (1983), however, presented growth parameters based on the common assumption that one band pair forms annually (annual band-pair interpretation). Therefore, growth rates obtained by Pratt & Casey (1983) were twice that of Cailliet et al. (1983) and could lead to age discrepancies of about 15 years for maximum estimated ages on the order of 30 from the annual band-pair interpretation. Serious consequences in the population dynamics could occur for this species if inputs are based on an invalid age interpretation. The latest Fishery Management Plan (FMP) for Highly Migratory Species (HMS), for example, adopted the biannual band pair deposition hypothesis because it apparently fit the observed growth patterns best (Pacific Fishery Management Council 2003). However, the ongoing uncertainty about the aging of the shortfin mako was acknowledged and it was recommended that an endeavor to resolve this issue …
Date: July 16, 2007
Creator: Ardizzone, D; Cailliet, G M; Natanson, L J; Andrews, A H; Kerr, L A & Brown, T A
System: The UNT Digital Library
CHEMICAL SLUDGE HEEL REMOVAL AT THE SAVANNAH RIVER SITE F TANK FARM CLOSURE PROJECT 8183 (open access)

CHEMICAL SLUDGE HEEL REMOVAL AT THE SAVANNAH RIVER SITE F TANK FARM CLOSURE PROJECT 8183

Chemical Sludge Removal (CSR) is the final waste removal activity planned for some of the oldest nuclear waste tanks located at the Savannah River Site (SRS) in Aiken, SC. In 2008, CSR will be used to empty two of these waste tanks in preparation for final closure. The two waste tanks chosen to undergo this process have previously leaked small amounts of nuclear waste from the primary tank into an underground secondary containment pan. CSR involves adding aqueous oxalic acid to the waste tank in order to dissolve the remaining sludge heel. The resultant acidic waste solution is then pumped to another waste tank where it will be neutralized and then stored awaiting further processing. The waste tanks to be cleaned have a storage capacity of 2.84E+06 liters (750,000 gallons) and a target sludge heel volume of 1.89E+04 liters (5,000 gallons) or less for the initiation of CSR. The purpose of this paper is to describe the CSR process and to discuss the most significant technical issues associated with the development of CSR.
Date: January 16, 2008
Creator: Thaxton, D & Timothy Baughman, T
System: The UNT Digital Library