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Adaptive Full-Spectrum Solar Energy Systems Cross-Cutting R&D on adaptive full-spectrum solar energy systems for more efficient and affordable use of solar energy in buildings and hybrid photobioreactors (open access)

Adaptive Full-Spectrum Solar Energy Systems Cross-Cutting R&D on adaptive full-spectrum solar energy systems for more efficient and affordable use of solar energy in buildings and hybrid photobioreactors

This RD&D project is a multi-institutional effort to develop a hybrid solar lighting (HSL) system that transports daylight from a paraboloidal dish concentrator to a luminaire via a bundle of polymer fiber optics. The luminaire can be a device to distribute sunlight into a space for the production of algae for CO{sub 2} sequestration or it can be a device that is a combination of daylighting and electric lighting for space/task lighting. In this project, the sunlight is collected using a one-meter paraboloidal concentrator dish with two-axis tracking. For the third generation (beta) system, the secondary mirror is an ellipsoidal mirror that directs the visible light into a bundle of 3 mm diameter fibers. The IR spectrum is filtered out to minimize unnecessary heating at the fiber entrance region. This report describes the major achievements from this research that began in August 2001.
Date: March 30, 2006
Creator: Wood, Byard & Kim, Kwang
Object Type: Report
System: The UNT Digital Library
Simple Estimates of Collisional Excitation Cross Sections (open access)

Simple Estimates of Collisional Excitation Cross Sections

N/A
Date: March 1, 2006
Creator: M., Blaskiewicz
Object Type: Report
System: The UNT Digital Library
Warm Calibration Measurements of the 1.3 GHz Electron Gun (open access)

Warm Calibration Measurements of the 1.3 GHz Electron Gun

N/A
Date: March 1, 2006
Creator: H., Hahn
Object Type: Report
System: The UNT Digital Library
Radiolytic Degradation of Urethane Foam Used for Encapsulation of Contaminated Componets (open access)

Radiolytic Degradation of Urethane Foam Used for Encapsulation of Contaminated Componets

None
Date: March 1, 2006
Creator: DelCul, Guillermo D; Simmons, C. M.; Icenhour, Alan S & Singh, D.
Object Type: Report
System: The UNT Digital Library
The Dynamics of Adsorption on Clean and Adsorbate-Modified Transition Metal and Metal Oxide Surfaces (open access)

The Dynamics of Adsorption on Clean and Adsorbate-Modified Transition Metal and Metal Oxide Surfaces

Research directed toward understanding the dynamical factors governing the adsorption of molecules typically involved in heterogeneous catalytic processes has been continued. Adsorption is the first step in any catalytic process, and predictions of rates of adsorption are fundamental to calculations of rates of catalytic reactions. Dissociative adsorption can occur either directly upon impact with the surface or as the result of the migration of a temporarily trapped species across the surface. Alkane activation exhibits both of these pathways for reaction on metal surfaces. We have focused on the dynamics of dissociative adsorption of low molecular weight alkanes on single crystal surfaces of platinum group metals. The overall objective of these studies was to make a quantitative comparison of the dissociation probabilities of C{sub 2}-C{sub 4} alkanes on different metals in order to assess the effects of the structures of the different alkanes and the intrinsic differences of the metals on reactivity. First, an unusual and somewhat unexpected difference is observed in the reactivity of linear and branched alkanes. Further, the reactivity of each alkane is significantly higher on Pt(111) than on Pd(111). It has also been observed that the trapping probabilities for the alkanes are higher on Pd(111) due to …
Date: March 31, 2006
Creator: Madix, Robert J.
Object Type: Report
System: The UNT Digital Library
Comparison of Two Gas Selection Methodologies: An Application of Bayesian Model Averaging (open access)

Comparison of Two Gas Selection Methodologies: An Application of Bayesian Model Averaging

One goal of hyperspectral imagery analysis is the detection and characterization of plumes. Characterization includes identifying the gases in the plumes, which is a model selection problem. Two gas selection methods compared in this report are Bayesian model averaging (BMA) and minimum Akaike information criterion (AIC) stepwise regression (SR). Simulated spectral data from a three-layer radiance transfer model were used to compare the two methods. Test gases were chosen to span the types of spectra observed, which exhibit peaks ranging from broad to sharp. The size and complexity of the search libraries were varied. Background materials were chosen to either replicate a remote area of eastern Washington or feature many common background materials. For many cases, BMA and SR performed the detection task comparably in terms of the receiver operating characteristic curves. For some gases, BMA performed better than SR when the size and complexity of the search library increased. This is encouraging because we expect improved BMA performance upon incorporation of prior information on background materials and gases.
Date: March 31, 2006
Creator: Renholds, Andrea S.; Thompson, Sandra E.; Anderson, Kevin K. & Chilton, Lawrence K.
Object Type: Report
System: The UNT Digital Library
Non-Equilibrium Nanoscale Self-Organization (open access)

Non-Equilibrium Nanoscale Self-Organization

Self-organized one- and two-dimensional arrays of nanoscale surface features ("ripples" and "dots") sometimes form spontaneously on initially flat surfaces eroded by a directed ion beam in a process called "sputter patterning". Experiments on this sputter patterning process with focused and unfocused ion beams, combined with theoretical advances, have been responsible for a number of scientific advances. Particularly noteworthy are (i) the discovery of propagative, rather than dissipative, behavior under some ion erosion conditions, permitting a pattern to be fabricated at a large length scale and propagated over large distances while maintaining, or even sharpening, the sharpest features; (ii) the first demonstration of guided self-organization of sputter patterns, along with the observation that defect density is minimized when the spacing between boundaries is near an integer times the natural spatial period; and (iii) the discovery of metastability of smooth surfaces, which contradicts the nearly universally accepted linear stability theory that predicts that any surface is linearly unstable to sinusoidal perturbations of some wave vector.
Date: March 9, 2006
Creator: Aziz, Michael J
Object Type: Report
System: The UNT Digital Library
A STRUCTURAL INTEGRITY EVALUATION OF THE TANK FARM WASTE TRANSFER SYSTEM (open access)

A STRUCTURAL INTEGRITY EVALUATION OF THE TANK FARM WASTE TRANSFER SYSTEM

Radioactive supernate, salt, and/or sludge wastes (i.e., high level wastes) are confined in 49 underground storage tanks at the Savannah River Site (SRS). The waste is transported between tanks within and between the F and H area tank farms and other facilities on site via underground and a limited number of aboveground transfer lines. The Department of Energy - Savannah River Operations Office (DOE-SR) performed a comprehensive assessment of the structural integrity program for the Tank Farm waste transfer system at the SRS. This document addresses the following issues raised during the DOE assessment: (1) Inspections of failed or replaced transfer lines indicated that the wall thickness of some core and jacket piping is less than nominal; (2) No corrosion allowance is utilized in the transfer line structural qualification calculations. No basis for neglecting corrosion was provided in the calculations; (3) Wall loss due to erosion is not addressed in the transfer line structural qualification calculations; and (4) No basis is provided for neglecting intergranular stress corrosion cracking in the transfer line structural qualification calculations. The common theme in most of these issues is the need to assess the potential for occurrence of material degradation of the transfer line piping. …
Date: March 9, 2006
Creator: Wiersma, B.
Object Type: Report
System: The UNT Digital Library
Structural health monitoring of wind turbine blades : SE 265 Final Project. (open access)

Structural health monitoring of wind turbine blades : SE 265 Final Project.

ACME Wind Turbine Corporation has contacted our dynamic analysis firm regarding structural health monitoring of their wind turbine blades. ACME has had several failures in previous years. Examples are shown in Figure 1. These failures have resulted in economic loss for the company due to down time of the turbines (lost revenue) and repair costs. Blade failures can occur in several modes, which may depend on the type of construction and load history. Cracking and delamination are some typical modes of blade failure. ACME warranties its turbines and wishes to decrease the number of blade failures they have to repair and replace. The company wishes to implement a real time structural health monitoring system in order to better understand when blade replacement is necessary. Because of warranty costs incurred to date, ACME is interested in either changing the warranty period for the blades in question or predicting imminent failure before it occurs. ACME's current practice is to increase the number of physical inspections when blades are approaching the end of their fatigue lives. Implementation of an in situ monitoring system would eliminate or greatly reduce the need for such physical inspections. Another benefit of such a monitoring system is that …
Date: March 23, 2006
Creator: Barkley, W. C. (Walter C.); Jacobs, Laura D.; Rutherford, A. C. (Amanda C.) & Puckett, Anthony
Object Type: Report
System: The UNT Digital Library
Effect of Centrifugal Transverse Wakefield for Microbunch in Bend (open access)

Effect of Centrifugal Transverse Wakefield for Microbunch in Bend

We calculate centrifugal force for a short bunch in vacuum moving in a circular orbit and estimate the emittance growth of the beam in a bend due to this force. Many of the basic features of the coherent synchrotron radiation (CSR) of short bunches and its effect on beam dynamics in accelerators are now well established. The effect is usually described in terms of the longitudinal force, or wakefield, that causes the energy loss in the beam, and also redistributes the energy between the particles by accelerating the head and decelerating the tail of the bunch. Coherent radiation becomes most important for short bunches and high currents. More subtle features of CSR such as transition effect due to the entrance to and exit from the bend, CSR force in the undulator, and shielding due to the close metallic boundaries have been also studied. Much less is known about the transverse force in a short bunch moving on a circular orbit. The problem has been treated in several papers beginning from R. Talman's work, who pointed out that the centrifugal force of a rotating bunch can result in a noticeable tune shift of betatron oscillations. Later, an important correction to the …
Date: March 22, 2006
Creator: Stupakov, G. V.
Object Type: Article
System: The UNT Digital Library
Nuclear Gamma-Ray Spectroscopy at the Limit of Particle Spectroscopy (open access)

Nuclear Gamma-Ray Spectroscopy at the Limit of Particle Spectroscopy

The research project ''Nuclear Gamma-Ray Spectroscopy at the Limit of Particle Stability'' with sponsor ID ''DE-FG02-04ER41334'' started late-summer 2004 and aims at the investigation of highly excited low-spin states of selected key-nuclei in the vicinity of the particle separation threshold by means of high-resolution gamma-ray spectroscopy in electromagnetic excitation reactions. This work addresses nuclear structures with excitation energies close to the binding energy or highly excited off-yrast states in accordance with the NSAC milestones. In 2005 the program was extended towards additional use of virtual photons and theoretical description of the low-lying collective excitations in the well deformed nuclei.
Date: March 29, 2006
Creator: Pietralla, Dr. Norbert
Object Type: Report
System: The UNT Digital Library
Possible Rhic Upgrades With Superbunches. (open access)

Possible Rhic Upgrades With Superbunches.

None
Date: March 7, 2006
Creator: Fischer, W.; Blaskiewicz, M. & Wei, J.
Object Type: Article
System: The UNT Digital Library
Innovative Distributed Power Grid Interconnection and Control Systems: Final Report, December 11, 2000 - August 30, 2005 (open access)

Innovative Distributed Power Grid Interconnection and Control Systems: Final Report, December 11, 2000 - August 30, 2005

The contract goal was to further advance distributed generation in the marketplace by making installations more cost-effective and compatible with existing systems. This was achieved by developing innovative grid interconnection and control systems.
Date: March 1, 2006
Creator: DePodesta, K.; Birlingmair, D. & West, R.
Object Type: Report
System: The UNT Digital Library
Temperature-Dependent Diffusion Coefficients from ab initio Computations: Hydrogen in Nickel (open access)

Temperature-Dependent Diffusion Coefficients from ab initio Computations: Hydrogen in Nickel

The temperature-dependent mass diffusion coefficient is computed using transition state theory. Ab initio supercell phonon calculations of the entire system provide the attempt frequency, the activation enthalpy, and the activation entropy as a function of temperature. Effects due to thermal lattice expansion are included and found to be significant. Numerical results for the case of hydrogen in nickel demonstrate a strong temperature dependence of the migration enthalpy and entropy. Trapping in local minima along the diffusion path has a pronounced effect especially at low temperatures. The computed diffusion coefficients with and without trapping bracket the available experimental values over the entire temperature range between 0 and 1400 K.
Date: March 16, 2006
Creator: Wimmer, Erich; Wolf, Walter; Sticht, Jurgen; Saxe, Paul; Geller, Clint; Najafabadi, Reza et al.
Object Type: Report
System: The UNT Digital Library
AgraPure Mississippi Biomass Project (open access)

AgraPure Mississippi Biomass Project

The AgraPure Mississippi Biomass project was a congressionally directed project, initiated to study the utilization of Mississippi agricultural byproducts and waste products in the production of bio-energy and to determine the feasibility of commercialization of these agricultural byproducts and waste products as feedstocks in the production of energy. The final products from this project were two business plans; one for a Thermal plant, and one for a Biodiesel/Ethanol plant. Agricultural waste fired steam and electrical generating plants and biodiesel plants were deemed the best prospects for developing commercially viable industries. Additionally, oil extraction methods were studied, both traditional and two novel techniques, and incorporated into the development plans. Mississippi produced crop and animal waste biomasses were analyzed for use as raw materials for both industries. The relevant factors, availability, costs, transportation, storage, location, and energetic value criteria were considered. Since feedstock accounts for more than 70 percent of the total cost of producing biodiesel, any local advantages are considered extremely important in developing this particular industry. The same factors must be evaluated in assessing the prospects of commercial operation of a steam and electrical generation plant. Additionally, the access to the markets for electricity is more limited, regulated and tightly …
Date: March 31, 2006
Creator: Blackwell,D.A; Broadhead, L.W. & Harrell, W.J.
Object Type: Report
System: The UNT Digital Library
First direct two-sided bound on the B0(s) oscillation frequency (open access)

First direct two-sided bound on the B0(s) oscillation frequency

The authors report the first direct two-sided bound on the B{sub s}{sup 0} oscillation frequency using a large sample of B{sub s}{sup 0} semileptonic decays corresponding to approximately 1 fb{sup -1} of integrated luminosity collected by the D0 experiment in 2002-2006 during Run II of the Fermilab Tevatron Collider. The flavor (i.e., B{sub s}{sup 0} or B{sub s}{sup 0}) of the B{sub s}{sup 0} meson at the time of production was found using an opposite-side tagging technique, and the flavor at the time of decay was determined from the charge of the muon in the partially reconstructed decay B{sub s}{sup 0} {yields} {mu}{sup +} D{sub s}{sup -}X, D{sub s}{sup -} {yields} {phi}{pi}{sup -}, {phi} {yields} K{sup +}K{sup -}. A likelihood scan over the oscillation frequency, {Delta}m{sub s}, gives a most probable value of 19 ps{sup -1} and a range of 17 < {Delta}m{sub s} < 21 ps{sup -1} at the 90% C.L. At {Delta}m{sub s} = 19 ps{sup -1}, the amplitude method yields a result that deviates from the hypothesis of an oscillation amplitude of zero by 2.5 standard deviations, corresponding to a two-sided C.L. of 1%.
Date: March 1, 2006
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
QCD THERMODYNAMICS WITH ALMOST REALISTIC QUARK MASSES. (open access)

QCD THERMODYNAMICS WITH ALMOST REALISTIC QUARK MASSES.

None
Date: March 18, 2006
Creator: SCHMIDT, C.
Object Type: Article
System: The UNT Digital Library
Concentration Ratios for Cesium and Strontium in Produce Near Los Alamos (open access)

Concentration Ratios for Cesium and Strontium in Produce Near Los Alamos

The ratios of the concentrations of radionuclides in produce (fruits, vegetables, and grains) to the concentrations in the soil have been measured for cesium and strontium at locations near Los Alamos. The Soil, Foodstuffs, and Biota Team of the Meteorology and Air Quality Group of the Los Alamos National Laboratory (LANL) obtained the data at locations within a radius of 50 miles of LANL. The concentration ratios are in good agreement with previous measurements: 0.01 to 0.06 for cesium-137 and 0.1 to 0.5 for strontium-90 (wet-weight basis).
Date: March 1, 2006
Creator: S. Salazar, M.McNaughton, P.R. Fresquez
Object Type: Report
System: The UNT Digital Library
BUILDING MATERIALS MADE FROM FLUE GAS DESULFURIZATION BY-PRODUCTS (open access)

BUILDING MATERIALS MADE FROM FLUE GAS DESULFURIZATION BY-PRODUCTS

Flue gas desulphurization (FGD) materials are produced in abundant quantities by coal burning utilities. Due to environmental restrains, flue gases must be ''cleaned'' prior to release to the atmosphere. They are two general methods to ''scrub'' flue gas: wet and dry. The choice of scrubbing material is often defined by the type of coal being burned, i.e. its composition. Scrubbing is traditionally carried out using a slurry of calcium containing material (slaked lime or calcium carbonate) that is made to contact exiting flue gas as either a spay injected into the gas or in a bubble tower. The calcium combined with the SO{sub 2} in the gas to form insoluble precipitates. Some plants have been using dry injection of these same materials or their own Class C fly ash to scrub. In either case the end product contains primarily hannebachite (CaSO{sub 3} {center_dot} 1/2H{sub 2}O) with smaller amounts of gypsum (CaSO{sub 4} {center_dot} 2H{sub 2}O). These materials have little commercial use. Experiments were carried out that were meant to explore the feasibility of using blends of hannebachite and fly ash mixed with concentrated sodium hydroxide to make masonry products. The results suggest that some of these mixtures could be used …
Date: March 30, 2006
Creator: Grutzeck, Michael W.; DiCola, Maria & Brenner, Paul
Object Type: Report
System: The UNT Digital Library
DOUBLE SHELL TANK (DST) EMERGENCY PUMPING GUIDE (open access)

DOUBLE SHELL TANK (DST) EMERGENCY PUMPING GUIDE

This document provides preplanning necessary to expeditiously remove any waste that may leak from the primary tank to the secondary tank for Hanford's 28 DSTs. The strategy is described, applicable emergency procedures are referenced, and transfer routes and pumping equipment for each tank are identified.
Date: March 17, 2006
Creator: REBERGER, D.W.
Object Type: Report
System: The UNT Digital Library
Advances in HFE Methods and Their Implications for Regulatory Reviews. (open access)

Advances in HFE Methods and Their Implications for Regulatory Reviews.

There is renewed interest in the United States (U.S.) to construct new Generation III and III+ reactors within the next decade and Generation IV reactors in the future. Licensing by the U.S. Nuclear Regulatory Commission (NRC) is a significant consideration and these new plants may pose new challenges. One such challenge is the advances in human factors engineering (HFE) methods that are used. These methods are used to design and evaluate the HFE aspects of a plant, such as the human-system interface (HSI). These methods are important because NRC HFE reviews are design process oriented, thus, the criteria are mostly technology neutral with regard to reactor design.[1] However, the HFE review criteria are not neutral with respect to the HFE methods that are used as part of the design process This will be important for new reactor reviews because the diversity of reactor types, HSIs, and operational concepts will increase, especially for Generation III+ and IV plants. Thus the NRC is conducting research to identify advances in HFE methods and to develop additional guidance to address their review.
Date: March 21, 2006
Creator: O'hara, J.; Persensky, J. & Szabo, A.
Object Type: Article
System: The UNT Digital Library
Development of Petroluem Residua Solubility Measurement Methodology: Final Report (open access)

Development of Petroluem Residua Solubility Measurement Methodology: Final Report

In the present study an existing spectrophotometry system was upgraded to provide high-resolution ultraviolet (UV), visible (Vis), and near infrared (NIR) analyses of test solutions to measure the relative solubilities of petroleum residua dissolved in eighteen test solvents. Test solutions were prepared by dissolving ten percent petroleum residue in a given test solvent, agitating the mixture, followed by filtration and/or centrifugation to remove insoluble materials. These solutions were finally diluted with a good solvent resulting in a supernatant solution that was analyzed by spectrophotometry to quantify the degree of dissolution of a particular residue in the suite of test solvents that were selected. Results obtained from this approach were compared with spot-test data (to be discussed) obtained from the cosponsor.
Date: March 1, 2006
Creator: Redelius, Per
Object Type: Report
System: The UNT Digital Library
Post-Closure RCRA Groundwater Monitoring Plan for the 216-S-10 Pond and Ditch (open access)

Post-Closure RCRA Groundwater Monitoring Plan for the 216-S-10 Pond and Ditch

The purpose of this plan is to provide a post-closure groundwater monitoring program for the 216-S-10 Pond and Ditch (S-10) treatment, storage, and/or disposal (TSD) unit. The plan incorporates the sum of knowledge about the potential for groundwater contamination to originate from the S-10, including groundwater monitoring results, hydrogeology, and operational history. The S-10 has not received liquid waste since October 1991. The closure of S-10 has been coordinated with the 200-CS-1 source operable unit in accordance with the Tri-Party Agreement interim milestones M-20-39 and M-15-39C. The S-10 is closely situated among other waste sites of very similar operational histories. The proximity of the S-10 to the other facilities (216-S-17 pond, 216-S-11 Pond, 216-S-5,6 cribs, 216-S-16 ditch and pond, and 216-U-9 ditch) indicate that at least some observed groundwater contamination beneath and downgradient of S-10 could have originated from waste sites other than S-10. Hence, it may not be feasible to strictly discriminate between the contributions of each waste site to groundwater contamination beneath the S-10. A post-closure groundwater monitoring network is proposed that will include the drilling of three new wells to replace wells that have gone dry. When completed, the revised network will meet the intent for groundwater …
Date: March 17, 2006
Creator: Barnett, D BRENT.; Williams, Bruce A.; Chou, Charissa J. & Hartman, Mary J.
Object Type: Report
System: The UNT Digital Library
Solar Trough Organic Rankine Electricity System (STORES) Stage 1: Power Plant Optimization and Economics; November 2000 -- May 2005 (open access)

Solar Trough Organic Rankine Electricity System (STORES) Stage 1: Power Plant Optimization and Economics; November 2000 -- May 2005

Report regarding a Stage 1 Study to further develop the concept of the Solar Trough Organic Rankine Cycle Electricity Systems (STORES).
Date: March 1, 2006
Creator: Prabhu, E.
Object Type: Report
System: The UNT Digital Library