States

PROPOSAL FOR A SILICON VERTEX TRACKER (VTX) FOR THE PHENIX EXPERIMENT. (open access)

PROPOSAL FOR A SILICON VERTEX TRACKER (VTX) FOR THE PHENIX EXPERIMENT.

We propose the construction of a Silicon Vertex Tracker (VTX) for the PHENIX experiment at RHIC. The VTX will substantially enhance the physics capabilities of the PHENIX central arm spectrometers. Our prime motivation is to provide precision measurements of heavy-quark production (charm and beauty) in A+A, p(d)+A, and polarized p+p collisions. These are key measurements for the future RHIC program, both for the heavy ion program as it moves from the discovery phase towards detailed investigation of the properties of the dense nuclear medium created in heavy ion collisions, and for the exploration of the nucleon spin-structure functions. In addition, the VTX will also considerably improve other measurements with PHENIX. The main physics topics addressed by the VTX are: (1) Hot and dense strongly interacting matter--Potential enhancement of charm production; Open beauty production; Flavor dependence of jet quenching and QCD energy loss; Accurate charm reference for quarkonium; Thermal dilepton radiation; High p{sub T} phenomena with light flavors above 10-15 GeV/c in p{sub T}; and Upsilon spectroscopy in the e{sup +}e{sup -} decay channel. (2) Gluon spin structure of the nucleon--{Delta}G/G with charm; {Delta}G/G with beauty; and x dependence of {Delta}G/G with {gamma}-jet correlations. (3) Nucleon structure in nuclei--Gluon shadowing over …
Date: March 30, 2004
Creator: AKIBA,Y.
Object Type: Report
System: The UNT Digital Library
Hydrogen Storage Properties of Magnesium Base Nanostructured Composite Materials (open access)

Hydrogen Storage Properties of Magnesium Base Nanostructured Composite Materials

In this work, nanostructured composite materials have been synthesized using the mechanical alloying process. The new materials produced have been investigated by X-ray diffraction (XRD), transition electron microscope (TEM), scanning electron microscope (SEM) and electron energy dispersion spectrum (EDS) for their phase compositions, crystal structure, grain size, particle morphology and the distribution of catalyst element. Hydrogen storage capacities and the hydriding-dehydriding kinetics of the new materials have been measured at different temperatures using a Sieverts apparatus. It is observed that mechanical alloying accelerates the hydrogenation kinetics of the magnesium based materials at low temperature, but a high temperature must be provided to release the absorbed hydrogen from the hydrided magnesium based materials. It is believed that the dehydriding temperature is largely controlled by the thermodynamic configuration of magnesium hydride. Doping Mg-Ni nano/amorphous composite materials with lanthanum reduces the hydriding and dehydriding temperature. Although the stability of MgH2 can not be easily reduced by ball milling alone, the results suggest the thermodynamic properties of Mg-Ni nano/amorphous composite materials can be alternated by additives such as La or other effective elements. Further investigation toward understanding the mechanism of additives will be rewarded.
Date: April 30, 2004
Creator: AU, M
Object Type: Article
System: The UNT Digital Library
Analysis of Premixed Charge Compression Ignition Combustion with a Sequential Fluid Mechanics-Multizone Chemical Kinetics Model (open access)

Analysis of Premixed Charge Compression Ignition Combustion with a Sequential Fluid Mechanics-Multizone Chemical Kinetics Model

We have developed a methodology for analysis of PCCI engines that applies to conditions in which there is some stratification in the air-fuel distribution inside the cylinder at the time of combustion. Our analysis methodology consists of two stages: first, a fluid mechanics code is used to determine temperature and equivalence ratio distributions as a function of crank angle, assuming motored conditions. The distribution information is then used for grouping the mass in the cylinder into a two-dimensional (temperature-equivalence ratio) array of zones. The zone information is then handed on to a detailed chemical kinetics model that calculates combustion, emissions and engine efficiency information. The methodology applies to situations where chemistry and fluid mechanics are weakly linked. The results of the multi-zone model have been compared to the results obtained from a fully integrated code, in which a chemical kinetics code is directly linked into a fluid mechanics code to calculate chemistry in every cell of the grid. The results show that the multi-zone model predicts burn duration and peak cylinder pressure with good accuracy. However, ignition timing predicted by the multi-zone model is sensitive to the transition angle between the fluid mechanics code and the chemical kinetics code. The …
Date: September 30, 2004
Creator: Aceves, S. M.; Flowers, D. L.; Espinosa-Loza, F.; Babajimopoulos, A. & Assanis, D. N.
Object Type: Article
System: The UNT Digital Library
Analysis of Homogeneous Charge Compression Ignition (HCCI) Engines for Cogeneration Applications (open access)

Analysis of Homogeneous Charge Compression Ignition (HCCI) Engines for Cogeneration Applications

This paper presents an evaluation of the applicability of Homogeneous Charge Compression Ignition Engines (HCCI) for small-scale cogeneration (less than 1 MWe) in comparison to five previously analyzed prime movers. The five comparator prime movers include stoichiometric spark-ignited (SI) engines, lean burn SI engines, diesel engines, microturbines and fuel cells. The investigated option, HCCI engines, is a relatively new type of engine that has some fundamental differences with respect to other prime movers. Here, the prime movers are compared by calculating electric and heating efficiency, fuel consumption, nitrogen oxide (NOx) emissions and capital and fuel cost. Two cases are analyzed. In Case 1, the cogeneration facility requires combined power and heating. In Case 2, the requirement is for power and chilling. The results show that the HCCI engines closely approach the very high fuel utilization efficiency of diesel engines without the high emissions of NOx and the expensive diesel fuel. HCCI engines offer a new alternative for cogeneration that provides a unique combination of low cost, high efficiency, low emissions and flexibility in operating temperatures that can be optimally tuned for cogeneration systems. HCCI engines are the most efficient technology that meets the oncoming 2007 CARB NOx standards for cogeneration …
Date: April 30, 2004
Creator: Aceves, S; Martinez-Frias, J & Reistad, G
Object Type: Article
System: The UNT Digital Library
Atmospheric Radiation Measurement Program Science Plan Current Status and Future Directions of the ARM Science Program (open access)

Atmospheric Radiation Measurement Program Science Plan Current Status and Future Directions of the ARM Science Program

The Atmospheric Radiation Measurement (ARM) Program has matured into one of the key programs in the U.S. Climate Change Science Program. The ARM Program has achieved considerable scientific success in a broad range of activities, including site and instrument development, atmospheric radiative transfer, aerosol science, determination of cloud properties, cloud modeling, and cloud parameterization testing and development. The focus of ARM science has naturally shifted during the last few years to an increasing emphasis on modeling and parameterization studies to take advantage of the long time series of data now available. During the next 5 years, the principal focus of the ARM science program will be to: • Maintain the data record at the fixed ARM sites for at least the next five years. • Improve significantly our understanding of and ability to parameterize the 3-D cloud-radiation problem at scales from the local atmospheric column to the global climate model (GCM) grid square. • Continue developing techniques to retrieve the properties of all clouds, with a special focus on ice clouds and mixed-phase clouds. • Develop a focused research effort on the indirect aerosol problem that spans observations, physical models, and climate model parameterizations. • Implement and evaluate an operational …
Date: October 30, 2004
Creator: Ackerman, TP; Genio, AD Del; Ellingson, RG; Ferrare, RA; Klein, SA; McFarquhar, GM et al.
Object Type: Report
System: The UNT Digital Library
Hydrogen Storage in metal-modified single-walled carbon nanotubes (open access)

Hydrogen Storage in metal-modified single-walled carbon nanotubes

It has been known for over thirty years that potassium-intercalated graphites can readily adsorb and desorb hydrogen at {approx}1 wt% at 77 K. These levels are much higher than can be attained in pure graphite, owing to a larger thermodynamic enthalpy of adsorption. This increased enthalpy may allow hydrogen sorption at higher temperatures. Potassium has other beneficial effects that enable the design of a new material: (a) Increased adsorption enthalpy in potassium-intercalated graphite compared to pure graphite reduces the pressure and increases the temperature required for a given fractional coverage of hydrogen adsorption. We expect the same effects in potassium-intercalated SWNTs. (b) As an intercalant, potassium separates c-axis planes in graphite. Potassium also separates the individual tubes of SWNTs ropes producing swelling and increased surface area. Increased surface area provides more adsorption sites, giving a proportionately higher capacity. The temperature of adsorption depends on the enthalpy of adsorption. The characteristic temperature is roughly the adsorption enthalpy divided by Boltzmann's constant, k{sub B}. For the high hydrogen storage capacity of SWNTs to be achieved at room temperature, it is necessary to increase the enthalpy of adsorption. Our goal for this project was to use metal modifications to the carbon surface of …
Date: April 30, 2004
Creator: Ahn, Dr.
Object Type: Report
System: The UNT Digital Library
Sandia National Laboratories Laboratory Directed Research and Development Program Annual Report: 2003 (open access)

Sandia National Laboratories Laboratory Directed Research and Development Program Annual Report: 2003

None
Date: July 30, 2004
Creator: Al-Ayat, R
Object Type: Report
System: The UNT Digital Library
Fabrication of Mo/Cu Multilayer and Bilayer Transition Edge Sensors (open access)

Fabrication of Mo/Cu Multilayer and Bilayer Transition Edge Sensors

We are developing cryogenic high-resolution x-ray, {gamma}-ray and neutron spectrometers based on superconducting Mo/Cu transition edge sensors. Here we discuss the sensor design for different applications, present the photolithographic fabrication techniques, and outline future detector development to increase spectrometer sensitivity.
Date: September 30, 2004
Creator: Ali, Z. A.; Drury, O. B.; Cunningham, M. F.; Chesser, J. M.; Barbee, T. W., Jr. & Friedrich, S.
Object Type: Article
System: The UNT Digital Library
Thermodynamics and Structure of Plutonium Alloys (open access)

Thermodynamics and Structure of Plutonium Alloys

The goal of this project was to investigate the chemical and structural effects of gallium and impurity elements, iron and nickel, on the phase behavior and crystallography of Pu-Ga alloys. This was done utilizing a theoretical chemical approach to predict binary and ternary alloy energetics, phase stability, and transformations. The modeling results were validated with experimental data derived from the synthesis of selected alloys and advanced characterization tools. The ultimate goal of this work was to develop a robust predictive capability for studying the thermodynamics and the structure-properties relationships in complex materials of high relevance to the Laboratory and DOE mission.
Date: January 30, 2004
Creator: Allen, P G; Turchi, P A & Gallegos, G F
Object Type: Report
System: The UNT Digital Library
A Hydrologic-Geophysical Method for Characterizing Flow and Transport Processes within the Vadose Zone (open access)

A Hydrologic-Geophysical Method for Characterizing Flow and Transport Processes within the Vadose Zone

The research objective of this project is to analyze the resolution of two different geophysical imaging techniques (electrical resistivity tomography and cross-borehole ground penetrating radar) for monitoring subsurface flow and transport processes within the vadose zone. This is being accomplished through a coupled approach involving large scale unsaturated flow modeling, petrophysical conversion of the resulting hydrologic properties to a geophysical property model and generation of synthetic geophysical data, followed by the inversion of the synthetic geophysical data. The resolution, benefits, and limitations of the geophysical techniques will then be ascertained through analysis and comparison of the images to the original hydrologic model. In addition, increasing levels of complexity will be added to the models as the project progresses through the addition of heterogeneity in the original hydrologic property model, and through uncertainty in the petrophysical relationship that couples the geophysical model to the hydrologic simulation.
Date: June 30, 2004
Creator: Alumbaugh, David L. & Brainard, James R.
Object Type: Report
System: The UNT Digital Library
Extractor Configurations for a Heavy Ion Fusion Volume Source (open access)

Extractor Configurations for a Heavy Ion Fusion Volume Source

In order for volume sources to deliver the current (e.g., 0.8 A of Ar{sup +} per module) and brightness necessary for heavy ion fusion (HIF), they must operate at high current density. Conventional extractor designs for 1 to 2 MeV run into voltage breakdown limitations and cannot easily produce the required current rise time (about one microsecond). We discuss two systems that can overcome these volume-extraction problems. Each uses multichannel preaccelerators followed by a single channel main accelerator. Fast beam switching is done in the low energy beamlet stages. A new design, utilizing concentric ring preaccelerators, was recently described for another application [2]. A more conventional design uses a large number of small round beamlets. In either case, the merging beamlets are angled toward the axis, a feature that dominates other focusing. By suitable adjustment of the individual angles, beam aberrations are reduced. Because of the high current density, the overall structure is compact. Emittance growth from merging of beamlets is calculated and scaling is discussed.
Date: August 30, 2004
Creator: Anderson, O. A.
Object Type: Article
System: The UNT Digital Library
ADVANCED MONITORING TO IMPROVE COMBUSTION TURBINE/COMBINED CYCLE CT/(CC) RELIABILITY, AVAILABILITY AND MAINTAINABILITY (RAM) (open access)

ADVANCED MONITORING TO IMPROVE COMBUSTION TURBINE/COMBINED CYCLE CT/(CC) RELIABILITY, AVAILABILITY AND MAINTAINABILITY (RAM)

Power generators are concerned with the maintenance costs associated with the advanced turbines that they are purchasing. Since these machines do not have fully established operation and maintenance (O&M) track records, power generators face financial risk due to uncertain future maintenance costs. This risk is of particular concern, as the electricity industry transitions to a competitive business environment in which unexpected O&M costs cannot be passed through to consumers. These concerns have accelerated the need for intelligent software-based diagnostic systems that can monitor the health of a combustion turbine in real time and provide valuable information on the machine's performance to its owner/operators. EPRI, Impact Technologies, Boyce Engineering, and Progress Energy have teamed to develop a suite of intelligent software tools integrated with a diagnostic monitoring platform that will, in real time, interpret data to assess the ''total health'' of combustion turbines. The Combustion Turbine Health Management System (CTHM) will consist of a series of dynamic link library (DLL) programs residing on a diagnostic monitoring platform that accepts turbine health data from existing monitoring instrumentation. The CTHM system will be a significant improvement over currently available techniques for turbine monitoring and diagnostics. CTHM will interpret sensor and instrument outputs, correlate …
Date: September 30, 2004
Creator: Angello, Leonard
Object Type: Report
System: The UNT Digital Library
Concepts of Model Verification and Validation (open access)

Concepts of Model Verification and Validation

Model verification and validation (V&V) is an enabling methodology for the development of computational models that can be used to make engineering predictions with quantified confidence. Model V&V procedures are needed by government and industry to reduce the time, cost, and risk associated with full-scale testing of products, materials, and weapon systems. Quantifying the confidence and predictive accuracy of model calculations provides the decision-maker with the information necessary for making high-consequence decisions. The development of guidelines and procedures for conducting a model V&V program are currently being defined by a broad spectrum of researchers. This report reviews the concepts involved in such a program. Model V&V is a current topic of great interest to both government and industry. In response to a ban on the production of new strategic weapons and nuclear testing, the Department of Energy (DOE) initiated the Science-Based Stockpile Stewardship Program (SSP). An objective of the SSP is to maintain a high level of confidence in the safety, reliability, and performance of the existing nuclear weapons stockpile in the absence of nuclear testing. This objective has challenged the national laboratories to develop high-confidence tools and methods that can be used to provide credible models needed for stockpile …
Date: October 30, 2004
Creator: B.H.Thacker; S.W.Doebling; F.M.Hemez; Anderson, M.C.; Pepin, J.E. & Rodriguez, E.A.
Object Type: Report
System: The UNT Digital Library
Effects of Ammonium Molybdophosphate (AMP) on Strontium, Actinides, and RCRA Metals in SRS Simulated Waste (open access)

Effects of Ammonium Molybdophosphate (AMP) on Strontium, Actinides, and RCRA Metals in SRS Simulated Waste

High Level Waste samples contain elevated concentrations of radioactive cesium requiring marked dilution of the waste to facilitate handling in non-shielded facilities. The authors developed a sample treatment protocol, using ammonium molybdophosphate (AMP) to remove sufficient cesium to allow handling of the samples with minimal dilution. The sample treatment protocol includes the following steps: pH adjust the sample to the range of 0.01 to 1.0 M acidity; mix 30 mL of acidified sample with 40-60 mg of AMP; cap and shake the mixture for 30-60 seconds; filter AMP from the liquid using 0.45 PTFE syringe filters; and send filtrate directly forward for analysis. To develop the method, SRTC performed a series of tests with three different salt solutions designed to determine the propensity of ammonium molybdophosphate (AMP) to bind some of the common analytes such as the actinides (Pu, Am, Np, U), strontium, or the metals (Ag, As, Ba, Cd, Cr, Hg, Pb, Se) regulated by the Resource Conservation Recovery Act (RCRA). SRTC also examined relevant literature to summarize reported interactions between AMP and other elements.
Date: April 30, 2004
Creator: BARNES, MARKJ
Object Type: Report
System: The UNT Digital Library
Gas Turbine Reheat Using In-Situ Combustion (open access)

Gas Turbine Reheat Using In-Situ Combustion

Gas turbine reheat is a well-known technique for increasing the power output of gas turbine, as well as the efficiency in combined cycle operation with higher heat recovery inlet temperatures. The technique also could allow development of an advanced high efficiency turbine with an additional stage, but without a higher inlet temperature. A novel reheat approach, with fuel added via internal passages in turbine airfoils, has been proposed [1]. This avoids the bulky and possible high-NOx discrete reheat combustors used in traditional approaches. The key questions regarding this approach are whether there is sufficient residence time at high temperature for fuel burnout, and whether increased emissions of NOx and CO result. This project examines the chemical kinetics basis of these questions. In the present task detailed chemical kinetics models were used to evaluate injection reheat combustion. Models used included a Siemens Westinghouse diffusion flame model, the set of CHEMKIN gas-phase kinetics equation solvers, and the GRI 3.0 detailed kinetics data base. These modules are called by a reheat-specific main program, which also provides them with data, including gas path conditions that change with distance through the turbine. Conceptually, injection could occur in either of two ways: (1) direct injection via …
Date: April 30, 2004
Creator: Bachovchin, D. M. & Lippert, T. E.
Object Type: Report
System: The UNT Digital Library
Ten Problems in Experimental Mathematics (open access)

Ten Problems in Experimental Mathematics

This article was stimulated by the recent SIAM ''100 DigitChallenge'' of Nick Trefethen, beautifully described in a recent book. Indeed, these ten numeric challenge problems are also listed in a recent book by two of present authors, where they are followed by the ten symbolic/numeric challenge problems that are discussed in this article. Our intent was to present ten problems that are characteristic of the sorts of problems that commonly arise in ''experimental mathematics''. The challenge in each case is to obtain a high precision numeric evaluation of the quantity, and then, if possible, to obtain a symbolic answer, ideally one with proof. Our goal in this article is to provide solutions to these ten problems, and in the process present a concise account of how one combines symbolic and numeric computation, which may be termed ''hybrid computation'', in the process of mathematical discovery.
Date: September 30, 2004
Creator: Bailey, David H.; Borwein, Jonathan M.; Kapoor, Vishaal & Weisstein, Eric
Object Type: Article
System: The UNT Digital Library
MIDWEST REGIONAL CARBON SEQUESTRATION PARTNERSHIP (MRCSP) (open access)

MIDWEST REGIONAL CARBON SEQUESTRATION PARTNERSHIP (MRCSP)

This is the first semiannual report for Phase I of the Midwest Carbon Sequestration Partnership (MRCSP). The project consists of nine tasks to be conducted over a two year period that started in October 2003. The makeup of the MRCSP and objectives are described. Progress on each of the active Tasks is also described and where possible, for those Tasks at some point of completion, a summary of results is presented.
Date: April 30, 2004
Creator: Ball, David; Bradbury, Judith; Lal, Rattan; Wickstrom, Larry; Gupta, Neeraj; Burns, Robert et al.
Object Type: Report
System: The UNT Digital Library
Operation of Solid Oxide Fuel Cell Anodes With Practical Hydrocarbon Fuels (open access)

Operation of Solid Oxide Fuel Cell Anodes With Practical Hydrocarbon Fuels

This work was carried out to achieve a better understanding of how SOFC anodes work with real fuels. The motivation was to improve the fuel flexibility of SOFC anodes, thereby allowing simplification and cost reduction of SOFC power plants. The work was based on prior results indicating that Ni-YSZ anode-supported SOFCs can be operated directly on methane and natural gas, while SOFCs with novel anode compositions can work with higher hydrocarbons. While these results were promising, more work was clearly needed to establish the feasibility of these direct-hydrocarbon SOFCs. Basic information on hydrocarbon-anode reactions should be broadly useful because reformate fuel gas can contain residual hydrocarbons, especially methane. In the Phase I project, we have studied the reaction mechanisms of various hydrocarbons--including methane, natural gas, and higher hydrocarbons--on two kinds of Ni-containing anodes: conventional Ni-YSZ anodes and a novel ceramic-based anode composition that avoid problems with coking. The effect of sulfur impurities was also studied. The program was aimed both at achieving an understanding of the interactions between real fuels and SOFC anodes, and providing enough information to establish the feasibility of operating SOFC stacks directly on hydrocarbon fuels. A combination of techniques was used to provide insight into the …
Date: July 30, 2004
Creator: Barnett, Scott A.; Liu, Jiang & Lin, Yuanbo
Object Type: Report
System: The UNT Digital Library
Developing State Policies Supportive of Bioenergy Development (open access)

Developing State Policies Supportive of Bioenergy Development

Working within the context of the Southern States Biobased Alliance (SSBA) and with officials in each state, the Southern States Energy Board (SSEB) is identifying bioenergy-related policies and programs within each state to determine their impact on the development, deployment or use of bioenergy. In addition, SSEB will determine which policies have impacted industry's efforts to develop, deploy or use biobased technologies or products. As a result, SSEB will work with the Southern States Biobased Alliance to determine how policy changes might address any negative impacts or enhance positive impacts.
Date: April 30, 2004
Creator: Baskin, Kathryn
Object Type: Report
System: The UNT Digital Library
Topical Report: Task 2.2 "Pressure Transmissibility" (open access)

Topical Report: Task 2.2 "Pressure Transmissibility"

The rate and amplitude of pressure transmission of various drilling fluids--particularly aphron drilling fluids--are measured in a long conduit and in sand packs to determine how pressure transmissibility can affect fluid invasion.
Date: July 30, 2004
Creator: Belkin, Arkadiy & Growcock, Fred
Object Type: Report
System: The UNT Digital Library
Improved Method for Quantifying Nonvolatile Residues on Surfaces and in Liquids (open access)

Improved Method for Quantifying Nonvolatile Residues on Surfaces and in Liquids

The objective of the project was to develop an improved method to quantify nonvolatile residues on surfaces and in liquids. The project accomplishments are summarized below: (1) ERA Systems, Inc., The MESERAN Company has designed, developed, built, evaluated, tested, and delivered MicroSolventEvaporator systems to KCP, Astro Pak, and Lockheed Martin, that automatically deposit and evaporate successive small quantities (5-10 microliters) of solvents onto clean reference surfaces. (2) ERA Systems, Inc., The MESERAN Company, and KCP have designed, procured, and evaluated stainless steel disks with specific machined grooves to be used as reference surfaces with the MicroSolventEvaporator and MESERAN Analyzers. (3) KCP evaluated various cleaning processes to easily clean the reference surfaces to acceptable levels. Even though some methods (or a combination of methods) may have worked better than others, an easy method that most companies could use to acceptably clean the disks was desired. Aqueous ultrasonic cleaning with Dirl Lum 603 (30 g per liter concentration) followed by flowing DI water and ultrasonic DI water rinses, nitrogen blow drying, and baking in a HEPA filtered oven at 220 F for 30 minutes proved to be a relatively simple method that most companies could use. (4) KCP developed calibrations of several …
Date: March 30, 2004
Creator: Benkovich, M. G.
Object Type: Report
System: The UNT Digital Library
Bounds on Elastic Constants for Random Polycrystals of Laminates (open access)

Bounds on Elastic Constants for Random Polycrystals of Laminates

A well-known result due to Hill provides an exact expression for the bulk modulus of any multicomponent elastic composite whenever the constituents are isotropic and the shear modulus is uniform throughout. Although no precise analog of Hill's result is available for the opposite case of uniform bulk modulus and varying shear modulus, it is shown here that some similar statements can be made for shear behavior of random polycrystals composed of laminates of isotropic materials. In particular, the Hashin-Shtrikman-type bounds of Peselnick, Meister, and Watt for random polycrystals composed of hexagonal (transversely isotropic) grains are applied to the problem of polycrystals of laminates. An exact product formula relating the Reuss estimate of bulk modulus and an effective shear modulus (of laminated grains composing the system) to products of the eigenvalues for quasi-compressional and quasi-uniaxial shear eigenvectors also plays an important role in the analysis of the overall shear behavior of the random polycrystal. When the bulk modulus is uniform in such a system, the equations are shown to reduce to a simple form that depends prominently on the uniaxial shear eigenvalue - as expected from physical arguments concerning the importance of uniaxial shear in these systems. One application of the …
Date: April 30, 2004
Creator: Berger, E. L.
Object Type: Article
System: The UNT Digital Library
NOx Control Options and Integration for US Coal Fired Boilers Quarterly Progress Report: April-June 2004 (open access)

NOx Control Options and Integration for US Coal Fired Boilers Quarterly Progress Report: April-June 2004

This is the sixteenth Quarterly Technical Report for DOE Cooperative Agreement No: DEFC26-00NT40753. The goal of the project is to develop cost effective analysis tools and techniques for demonstrating and evaluating low NOx control strategies and their possible impact on boiler performance for boilers firing US coals. The Electric Power Research Institute (EPRI) is providing co-funding for this program. During an unplanned outage, damage occurred to the electrochemical noise corrosion probes installed at the AEP Gavin plant; testing is expected to resume in August. The KEMCOP corrosion coupons were not affected by the unplanned outage; the coupons were removed and sent for analysis. BYU conducted a series of tests before the ISSR lab was relocated. Ammonia adsorption experiments provided clear evidence of the types of acidic sites present on catalyst surfaces. Data collected this quarter indicate that surface sulfation decreases Lewis acid site concentrations for all catalysts thus far studied, confirming that catalytic activity under commercial coal-based SCR conditions occurs primarily on Br{o}nsted acid sites and would be susceptible to basic impurities such as alkali and alkaline earth oxides, chlorides, and sulfates. SCR activity tests based on MS analysis showed that increasing sulfation generally increases NO reduction activity for both …
Date: June 30, 2004
Creator: Bockelie, Mike; Davis, Kevin; Linjewile, Temi; Senior, Connie; Eddings, Eric; Whitty, Kevin et al.
Object Type: Report
System: The UNT Digital Library
NOx Control Options and Integration for US Coal Fired Boilers Quarterly Progress Report: July-September 2004 (open access)

NOx Control Options and Integration for US Coal Fired Boilers Quarterly Progress Report: July-September 2004

This is the seventeenth Quarterly Technical Report for DOE Cooperative Agreement No: DEFC26-00NT40753. The goal of the project is to develop cost effective analysis tools and techniques for demonstrating and evaluating low NOx control strategies and their possible impact on boiler performance for boilers firing US coals. The Electric Power Research Institute (EPRI) is providing co-funding for this program. The SCR slipstream reactor was assembled and installed at Plant Gadsden this quarter. Safety equipment for ammonia had not been installed at the end of the quarter, but will be installed at the beginning of next quarter. The reactor will be started up next quarter. Four ECN corrosion probes were reinstalled at Gavin and collected corrosion data for approximately one month. Two additional probes were installed and removed after about 30 hours for future profilometry analysis. Preliminary analysis of the ECN probes, the KEMA coupons and the CFD modeling results all agree with the ultrasonic tube test measurements gathered by AEP personnel.
Date: September 30, 2004
Creator: Bockelie, Mike; Davis, Kevin; Shino, Connie Senior Darren; Swenson, Dave; Baxter, Larry; Bartholomew, Calvin et al.
Object Type: Report
System: The UNT Digital Library