Effect of 1-hydroxyethane-1,1-diphosphonic acid (HEDPA) on Partitioning of Np and Pu to Synthetic Boehmite (open access)

Effect of 1-hydroxyethane-1,1-diphosphonic acid (HEDPA) on Partitioning of Np and Pu to Synthetic Boehmite

The effect of 1-hydroxyethane-1,1-diphosphonic acid (HEDPA) on sorption of Np(V) and Pu(V) to synthetic boehmite ({gamma}-AlOOH) was examined a function of time and pH (between 4 to 11). Sorption of both elements in boehmite suspensions (1 M NaCl, 600 mg L{sup -1} boehmite) increased with increasing pH. Sorption edges for neptunium and plutonium occurred at approximately pH 8.0 and 6.6, respectively. After steady state partitioning was reached, HEDPA was added to the neptunium-boehmite and plutonium-boehmite suspensions. Neptunium and plutonium partitioning appears to be primarily affected by the formation of soluble Np:HEDPA and Pu:HEDPA complexes, the dissolution of boehmite promoted by HEDPA, and the precipitation of Np:HEDPA and Pu:HEDPA colloids. The results are discussed in terms of applicability of HEDPA-promoted dissolution as a waste reduction method in the treatment of sludge phases contained within high-level nuclear waste storage tanks.
Date: May 1, 2009
Creator: Powell, Brian A.; Rao, Linfeng & Nash, Kenneth L.
Object Type: Article
System: The UNT Digital Library
Effect of Channel Configurations for Tritium Transfer in Printed Circuit Heat Exchangers (open access)

Effect of Channel Configurations for Tritium Transfer in Printed Circuit Heat Exchangers

The Next Generation Nuclear Plant (NGNP), a very High temperature Gas-Cooled Reactor (VHTR) concept, will provide the first demonstration of a closed-loop Brayton cycle at a commercial scale of a few hundred megawatts electric and hydrogen production. The power conversion system (PCS) for the NGNP will take advantage of the significantly higher reactor outlet temperatures of the VHTR to provide higher efficiencies than can be achieved in the current generation of light water reactors. Besides demonstrating a system design that can be used directly for subsequent commercial deployment, the NGNP will demonstrate key technology elements that can be used in subsequent advanced power conversion systems for other Generation IV reactors. In anticipation of the design, development and procurement of an advanced power conversion system for the NGNP, the system integration of the NGNP and hydrogen plant was initiated to identify the important design and technology options that must be considered in evaluating the performance of the proposed NGNP. In the VHTR system, an intermediate heat exchanger (IHX), which transfers heat from the reactor core to the electricity or hydrogen production system is one key component, and its effectiveness is directly related to the system overall efficiency. In the VHTRs, the …
Date: May 1, 2009
Creator: Oh, Chang; Kim, Eung; Shrake, Robert & Patterson, Mike
Object Type: Article
System: The UNT Digital Library
Effect of Reacting Surface Density on the Overall Graphite Oxidation Rate (open access)

Effect of Reacting Surface Density on the Overall Graphite Oxidation Rate

Graphite oxidation in an air-ingress accident is presently a very important issue for the reactor safety of the very high temperature gas cooled-reactor (VHTR), the concept of the next generation nuclear plant (NGNP) because of its potential problems such as mechanical degradation of the supporting graphite in the lower plenum of the VHTR might lead to core collapse if the countermeasure is taken carefully. The oxidation process of graphite has known to be affected by various factors, including temperature, pressure, oxygen concentration, types of graphite, graphite shape and size, flow distribution, etc. However, our recent study reveals that the internal pore characteristics play very important roles in the overall graphite oxidation rate. One of the main issues regarding graphite oxidation is the potential core collapse problem that may occur following the degradation of graphite mechanical strength. In analyzing this phenomenon, it is very important to understand the relationship between the degree of oxidization and strength degradation. In addition, the change of oxidation rate by graphite oxidation degree characterization by burn-off (ratio of the oxidized graphite density to the original density) should be quantified because graphite strength degradation is followed by graphite density decrease, which highly affects oxidation rates and patterns. …
Date: May 1, 2009
Creator: Oh, Chang H.; Kim, Eung; Lim, Jong; Schultz, Richard & Petti, David
Object Type: Article
System: The UNT Digital Library
The effect of resist on the transfer of line-edge roughness spatial metrics from mask to wafer (open access)

The effect of resist on the transfer of line-edge roughness spatial metrics from mask to wafer

Mask contributors to line-edge roughness (LER) have recently been shown to be an issue of concern for both the accuracy of current resist evaluation tests as well the ultimate LER requirements for the 22-nm production node. More recently, it has been shown that the power spectral density of the mask-induced roughness, is markedly different than that of intrinsic resist roughness and thus potentially serves as a mechanism for distinguishing mask effects from resist effects in experimental results. Further considering stochastic resist effects, however, demonstrates that such a test would only be viable in cases where the resist effects are completely negligible in terms of their contribution to the total LER compared to the mask effects. The results presented here lead us to the surprising conclusion that it is indeed possible for mask contributors to be the dominant source of LER while the spatial characteristics of the LER remain indistinguishable from the fractal characteristics of resist-induced LER.
Date: May 1, 2009
Creator: Naulleau, Patrick & Gallatin, Gregg
Object Type: Article
System: The UNT Digital Library
Effects of radio transmitters on the behavior of Red-headed Woodpeckers. (open access)

Effects of radio transmitters on the behavior of Red-headed Woodpeckers.

ABSTRACT. Previous studies have revealed that radio-transmitters may affect bird behaviors, including feeding rates, foraging behavior, vigilance, and preening behavior. In addition, depending on the method of attachment, transmitters can potentially affect the ability of cavity-nesting birds to use cavities. Our objective was to evaluate effects of transmitters on the behavior of and use of cavities byRed-headedWoodpeckers (Melanerpes erythrocephalus). Using backpack harnesses, we attached 2.1-g transmitter packages that averaged 3.1% of body weight (range = 2.5–3.6%) to Red-headed Woodpeckers. We observed both radio-tagged (N = 23) and nonradio-tagged (N = 28) woodpeckers and determined the percentage of time spent engaged in each of five behaviors: flight, foraging, perching, preening, and territorial behavior. We found no difference between the two groups in the percentage of time engaged in each behavior. In addition, we found that transmitters had no apparent effect on use of cavities for roosting by radio-tagged woodpeckers (N = 25).We conclude that backpack transmitters weighing less than 3.6% of body weight had no impact on either their behavior or their ability to use cavities.
Date: May 1, 2009
Creator: Vukovich, Mark & Kilgo, John, C.
Object Type: Article
System: The UNT Digital Library
Effects of Transverse Physics on Nonlinear Evolution of Longitudinal Space-Charge Waves in Beams (open access)

Effects of Transverse Physics on Nonlinear Evolution of Longitudinal Space-Charge Waves in Beams

Longitudinal space-charge waves can introduce energy perturbations into charge particle beams and degrade the beam quality, which is critical to many modern applications of particle accelerators. Although many longitudinal phenomena arising from small perturbations can be explained by a one-dimensional cold fluid theory, nonlinear behavior of space-charge waves observed in experiments has not been well understood. In this paper, we summarize our recent investigation by means of more detailed measurements and self-consistent simulations. Combining the numerical capability of a PIC code, WARP, with the detailed initial conditions measured by our newly developed time resolved 6-D phase space mapping technique, we are able to construct a self consistent model for studying the complex physics of longitudinal dynamics of space-charge dominated beams. Results from simulation studies suggest that the unexplained nonlinear behavior of space-charge waves may be due to transverse mismatch or misalignment of beams.
Date: May 1, 2009
Creator: K. Tian, I. Haber, R.A. Kishek, P.G. O'Shea, M. Reiser, D. Stratakis
Object Type: Article
System: The UNT Digital Library
Electromagnetic SCRF Cavity Tuner (open access)

Electromagnetic SCRF Cavity Tuner

A novel prototype of SCRF cavity tuner is being designed and tested at Fermilab. This is a superconducting C-type iron dominated magnet having a 10 mm gap, axial symmetry, and a 1 Tesla field. Inside the gap is mounted a superconducting coil capable of moving {+-} 1 mm and producing a longitudinal force up to {+-} 1.5 kN. The static force applied to the RF cavity flanges provides a long-term cavity geometry tuning to a nominal frequency. The same coil powered by fast AC current pulse delivers mechanical perturbation for fast cavity tuning. This fast mechanical perturbation could be used to compensate a dynamic RF cavity detuning caused by cavity Lorentz forces and microphonics. A special configuration of magnet system was designed and tested.
Date: May 1, 2009
Creator: Kashikhin, V.; Borissov, E.; Foster, G.W.; Makulski, A.; Pischalnikov, Y.; Khabiboulline, T. et al.
Object Type: Article
System: The UNT Digital Library
The electron transfer system of syntrophically grown Desulfovibrio vulgaris (open access)

The electron transfer system of syntrophically grown Desulfovibrio vulgaris

Interspecies hydrogen transfer between organisms producing and consuming hydrogen promotes the decomposition of organic matter in most anoxic environments. Although syntrophic couplings between hydrogen producers and consumers are a major feature of the carbon cycle, mechanisms for energy recovery at the extremely low free energies of reactions typical of these anaerobic communities have not been established. In this study, comparative transcriptional analysis of a model sulfate-reducing microbe, Desulfovibrio vulgaris Hildenborough, suggested the use of alternative electron transfer systems dependent upon growth modality. During syntrophic growth on lactate with a hydrogenotrophic methanogen, D. vulgaris up-regulated numerous genes involved in electron transfer and energy generation when compared with sulfate-limited monocultures. In particular, genes coding for the putative membrane-bound Coo hydrogenase, two periplasmic hydrogenases (Hyd and Hyn) and the well-characterized high-molecular weight cytochrome (Hmc) were among the most highly expressed and up-regulated. Additionally, a predicted operon coding for genes involved in lactate transport and oxidation exhibited up-regulation, further suggesting an alternative pathway for electrons derived from lactate oxidation during syntrophic growth. Mutations in a subset of genes coding for Coo, Hmc, Hyd and Hyn impaired or severely limited syntrophic growth but had little affect on growth via sulfate-respiration. These results demonstrate that syntrophic …
Date: May 1, 2009
Creator: Walker, Christopher B.; He, Zhili; Yang, Zamin K.; Ringbauer, Joseph A., Jr.; He, Qiang; Zhou, Jizhong et al.
Object Type: Article
System: The UNT Digital Library

Energy Storage R&D: Thermal Management Studies and Modeling

Here we summarize NREL's FY09 energy storage R&D studies in the areas of 1. thermal characterization and analysis, 2. cost, life, and performance trade-off studies, and 3. thermal abuse modeling.
Date: May 1, 2009
Creator: Pesaran, A. A.
Object Type: Presentation
System: The UNT Digital Library
Enhanced Method for Cavity Impedance Calculations (open access)

Enhanced Method for Cavity Impedance Calculations

With the proposal of medium to high average current accelerator facilities the demand for cavities with extremely low Higher Order Mode (HOM) impedances is increasing. Modern numerical tools are still under development to more thoroughly predict impedances that need to take into account complex absorbing boundaries and lossy materials. With the usually large problem size it is preferable to utilize massive parallel computing when applicable and available. Apart from such computational issues, we have developed methods using available computer resources to enhance the information that can be extracted from a cavities? wakefield computed in time domain. In particular this is helpful for a careful assessment of the extracted RF power and the mitigation of potential beam break-up or emittance diluting effects, a figure of merit for the cavity performance. The method is described as well as an example of its implementation.
Date: May 1, 2009
Creator: Marhauser, Frank; Rimmer, Robert; Tian, Kai & Wang, Haipeng
Object Type: Article
System: The UNT Digital Library
Ensuring data consistency over CMS distributed computing system (open access)

Ensuring data consistency over CMS distributed computing system

CMS utilizes a distributed infrastructure of computing centers to custodially store data, to provide organized processing resources, and to provide analysis computing resources for users. Integrated over the whole system, even in the first year of data taking, the available disk storage approaches 10 petabytes of space. Maintaining consistency between the data bookkeeping, the data transfer system, and physical storage is an interesting technical and operations challenge. In this paper we will discuss the CMS effort to ensure that data is consistently available at all computing centers. We will discuss the technical tools that monitor the consistency of the catalogs and the physical storage as well as the operations model used to find and solve inconsistencies.
Date: May 1, 2009
Creator: Rossman, Paul
Object Type: Article
System: The UNT Digital Library
Evaluating indoor exposure modeling alternatives for LCA: A case study in the vehicle repair industry (open access)

Evaluating indoor exposure modeling alternatives for LCA: A case study in the vehicle repair industry

We evaluated three exposure models with data obtained from measurements among workers who use"aerosol" solvent products in the vehicle repair industry and with field experiments using these products to simulate the same exposure conditions. The three exposure models were the: 1) homogeneously-mixed-one-box model, 2) multi-zone model, and 3) eddy-diffusion model. Temporally differentiated real-time breathing zone volatile organic compound (VOC) concentration measurements, integrated far-field area samples, and simulated experiments were used in estimating parameters, such as emission rates, diffusivity, and near-field dimensions. We assessed differences in model input requirements and their efficacy for predictive modeling. The One-box model was not able to resemble the temporal profile of exposure concentrations, but it performed well concerning time-weighted exposure over extended time periods. However, this model required an adjustment for spatial concentration gradients. Multi-zone models and diffusion-models may solve this problem. However, we found that the reliable use of both these models requires extensive field data to appropriately define pivotal parameters such as diffusivity or near-field dimensions. We conclude that it is difficult to apply these models for predicting VOC exposures in the workplace. However, for comparative exposure scenarios in life-cycle assessment they may be useful.
Date: May 1, 2009
Creator: Demou, Evangelia; Hellweg, Stefanie; Wilson, Michael P.; Hammond, S. Katharine & McKone, Thomas E.
Object Type: Article
System: The UNT Digital Library
Evaluation of Candidate In-Pile Thermal Conductivity Techniques (open access)

Evaluation of Candidate In-Pile Thermal Conductivity Techniques

Thermophysical properties of materials must be known for proper design, test, and application of new fuels and structural properties in nuclear reactors. In the case of nuclear fuels during irradiation, the physical structure and chemical composition change as a function of time and position within the rod. Typically, thermal conductivity changes, as well as other thermophysical properties being evaluated during irradiation in a materials and test reactor, are measured out-of-pile in “hot-cells.” Repeatedly removing samples from a test reactor to make out-of-pile measurements is expensive, has the potential to disturb phenomena of interest, and only provide understanding of the sample's end state at the time each measurement is made. There are also limited thermophysical property data for advanced fuels. Such data are needed for the development of next generation reactors and advanced fuels for existing nuclear plants. Having the capacity to effectively and quickly characterize fuels and material properties during irradiation has the potential to improve the fidelity of nuclear fuel data and reduce irradiation testing costs.
Date: May 1, 2009
Creator: Fox, B.; Ban, H.; Daw, J.; Condie, K.; Knudson, D. & Rempe, J.
Object Type: Report
System: The UNT Digital Library
Evaluation of Integrated High Temperature Component Testing Needs (open access)

Evaluation of Integrated High Temperature Component Testing Needs

This paper describes the requirements for a large-scale component test capability to support the development of advanced nuclear reactor technology and their adaptation to commercial applications that advance U.S. energy economy, reliability, and security and reduce carbon emissions.
Date: May 1, 2009
Creator: Soto, Rafael; Duncan, David & Tonc, Vincent
Object Type: Report
System: The UNT Digital Library

Evaluation Study for Large Prismatic Lithium-Ion Cell Designs Using Multi-Scale Multi-Dimensional Battery Model

Addresses battery requirements for electric vehicles using a model that evaluates physical-chemical processes in lithium-ion batteries, from atomic variations to vehicle interface controls.
Date: May 1, 2009
Creator: Kim, G. H. & Smith, K.
Object Type: Presentation
System: The UNT Digital Library
Evaluations of Structural Failure Probabilities and Candidate Inservice Inspection Programs (open access)

Evaluations of Structural Failure Probabilities and Candidate Inservice Inspection Programs

The work described in this report applies probabilistic structural mechanics models to predict the reliability of nuclear pressure boundary components. These same models are then applied to evaluate the effectiveness of alternative programs for inservice inspection to reduce these failure probabilities. Results of the calculations support the development and implementation of risk-informed inservice inspection of piping and vessels. Studies have specifically addressed the potential benefits of ultrasonic inspections to reduce failure probabilities associated with fatigue crack growth and stress-corrosion cracking. Parametric calculations were performed with the computer code pc-PRAISE to generate an extensive set of plots to cover a wide range of pipe wall thicknesses, cyclic operating stresses, and inspection strategies. The studies have also addressed critical inputs to fracture mechanics calculations such as the parameters that characterize the number and sizes of fabrication flaws in piping welds. Other calculations quantify uncertainties associated with the inputs calculations, the uncertainties in the fracture mechanics models, and the uncertainties in the resulting calculated failure probabilities. A final set of calculations address the effects of flaw sizing errors on the effectiveness of inservice inspection programs.
Date: May 1, 2009
Creator: Khaleel, Mohammad A. & Simonen, Fredric A.
Object Type: Report
System: The UNT Digital Library
Executive summary of major NuMI lessons learned: a review of relevant meetings of Fermilab's DUSEL Beamline Working Group (open access)

Executive summary of major NuMI lessons learned: a review of relevant meetings of Fermilab's DUSEL Beamline Working Group

We have gained tremendous experience with the NuMI Project on what was a new level of neutrino beams from a high power proton source. We expect to build on that experience for any new long baseline neutrino beam. In particular, we have learned about some things which have worked well and/or where the experience is fairly directly applicable to the next project (e.g., similar civil construction issues including: tunneling, service buildings, outfitting, and potential claims/legal issues). Some things might be done very differently (e.g., decay pipe, windows, target, beam dump, and precision of power supply control/monitoring). The NuMI experience does lead to identification of critical items for any future such project, and what issues it will be important to address. The DUSEL Beamline Working Group established at Fermilab has been meeting weekly to collect and discuss information from that NuMI experience. This document attempts to assemble much of that information in one place. In this Executive Summary, we group relevant discussion of some of the major issues and lessons learned under seven categories: (1) Differences Between the NuMI Project and Any Next Project; (2) The Process of Starting Up the Project; (3) Decision and Review Processes; (4) ES&H: Environment, Safety, …
Date: May 1, 2009
Creator: Andrews, Mike; Appel, Jeffrey A.; Bogert, Dixon; Childress, Sam; Cossairt, Don; Griffing, William et al.
Object Type: Report
System: The UNT Digital Library
Experiments Performed in Substantiation of the Conditioning of BN-350 Spent Cesium Traps Using Lead or Lead-Bismuth Alloy Filling Technology (open access)

Experiments Performed in Substantiation of the Conditioning of BN-350 Spent Cesium Traps Using Lead or Lead-Bismuth Alloy Filling Technology

The technology of cleaning cesium radionuclides from sodium coolant at the BN-350 fast reactor was realized in the form of cesium traps of two types: stationary devices connected to the circuit that was to be cleaned and in-core devices installed into the core of reactor when it was not under operation. Carbon-graphite materials were used as sorbents to collect and concentrate radioactive cesium, accumulated in the BN-350 reactor circuits over the decades of their operation, in relatively small volume traps which provided effective radiation-safe conditions for personnel working in proximity to the coolant and equipment of the primary circuit during BN-350 decommissioning. Spent cesium traps, as products unfit for further use, represent solid radioactive wastes. The presence of chemically active sodium, potassium and cesium that are able to react violently with water results in series of problems related to their disposal in the Republic of Kazakhstan. Considering the technology of filling spent cesium traps with lead/lead-bismuth alloy as a priority one for their conditioning, evaluations for safety substantiation were implemented. A set of experiments was implemented aimed at verification of calculations performed in substantiation of the proposed technology: filling a full scale cesium trap mock-up with sodium followed by its …
Date: May 1, 2009
Creator: Romanenko, O.; Tazhibaeva, I.; Yakovlev, I.; Ivanov, A.; Wells, D.; Herrick, A. et al.
Object Type: Article
System: The UNT Digital Library
Fabrication and Measurement of 12 GeV Prototype Quadrupoles at Thomas Jefferson National Accelerator Facility (open access)

Fabrication and Measurement of 12 GeV Prototype Quadrupoles at Thomas Jefferson National Accelerator Facility

Jefferson Lab's Continuous Electron Beam Accelerator Facility (CEBAF) currently has a maximum beam energy of 6 GeV. The 12 GeV Upgrade Project will double the existing energy and is currently scheduled for completion in 2014. This doubling of energy requires modifications to the beam transport system which includes the addition of several new magnet designs and modifications to many existing designs. Prototyping efforts have been concluded for two different designs of quadrupole magnets required for the upgrade. The design, fabrication and measurement will be discussed.
Date: May 1, 2009
Creator: Tommy Hiatt, Mark Wiseman, Kenneth Baggett, J. Beck, Leigh Harwood, Joseph Meyers, Jeffrey Dail
Object Type: Article
System: The UNT Digital Library
A Family of L-band SRF Cavities for High Power Proton Driver Applications (open access)

A Family of L-band SRF Cavities for High Power Proton Driver Applications

Recent global interest in high duty factor or CW superconducting linacs with high average beam power highlights the need for robust and reliable SRF structures capable of delivering high average RF power to the beam with moderate HOM damping, low interception of halo and good efficiency. Potential applications include proton or H- drivers for spallation neutron sources, neutrino physics, waste transmutation, subcritical reactors, and high-intensity high-energy physics experiments. We describe a family of SRF cavities with a range of Betas capable of transporting beam currents in excess of 10 mA CW with large irises for minimal interception of halo and HOM and power couplers capable of supporting high average power operation. Goals include an efficient cell shape, high packing factor for efficient real-estate gradient and strong HOM damping to ensure stable beam operation,
Date: May 1, 2009
Creator: Robert Rimmer, Frank Marhauser
Object Type: Article
System: The UNT Digital Library
FCC Record, Volume 24, No. 6, Pages 4423 to 5282, April 13 - May 1, 2009 (open access)

FCC Record, Volume 24, No. 6, Pages 4423 to 5282, April 13 - May 1, 2009

Biweekly, comprehensive compilation of decisions, reports, public notices, and other documents of the U.S. Federal Communications Commission.
Date: May 2009
Creator: United States. Federal Communications Commission.
Object Type: Book
System: The UNT Digital Library
FCC Record, Volume 24, No. 7, Pages 5283 to 6184, May 4 - May 22, 2009 (open access)

FCC Record, Volume 24, No. 7, Pages 5283 to 6184, May 4 - May 22, 2009

Biweekly, comprehensive compilation of decisions, reports, public notices, and other documents of the U.S. Federal Communications Commission.
Date: May 2009
Creator: United States. Federal Communications Commission.
Object Type: Book
System: The UNT Digital Library
Federal Fleet Files, FEMP, Vol. 1, No. 1 - May 2009 (Fact Sheet) (open access)

Federal Fleet Files, FEMP, Vol. 1, No. 1 - May 2009 (Fact Sheet)

Monthly newsletter for the FEMP Federal Fleet Program that outlines vehicle, alternative fuel, infrastructure, and management strategy updates to Federal agencies.
Date: May 1, 2009
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Federal Register, Volume 74, Number 83, May 1, 2009, Pages 20201-20404 (open access)

Federal Register, Volume 74, Number 83, May 1, 2009, Pages 20201-20404

Daily publication of the U.S. Office of the Federal Register contains rules and regulations, proposed legislation and rule changes, and other notices, including "Presidential proclamations and Executive Orders, Federal agency documents having general applicability and legal effect, documents required to be published by act of Congress, and other Federal agency documents of public interest" (p. ii). Table of Contents starts on page iii.
Date: May 1, 2009
Creator: United States. Office of the Federal Register.
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library