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Failure analysis for the dual input quad NAND fate CD4011 under dormant storage conditions. (open access)

Failure analysis for the dual input quad NAND fate CD4011 under dormant storage conditions.

Several groups of plastic molded CD4011 were electrically tested as part of an Army dormant storage program. For this test, parts had been in storage in missile containers for 4.5 years. Eight of the parts (out of 1200) failed the electrical tests and were subsequently analyzed to determine the cause of the failures. The root cause was found to be corrosion of the unpassivated Al bondpads. No significant attack of the passivated Al traces was found. Seven of the eight failures occurred in parts stored on a preposition ship (Jeb Stuart), suggesting a link between the external environment and observed corrosion.
Date: November 1, 2004
Creator: Sorensen, Neil Robert
Object Type: Report
System: The UNT Digital Library
Arctic National Wildlife Refuge (ANWR): Controversies for the 108th Congress (open access)

Arctic National Wildlife Refuge (ANWR): Controversies for the 108th Congress

This report discusses one major element of the energy debate in the 108th Congress, which has been whether to approve energy development in the Arctic National Wildlife Refuge (ANWR) in northeastern Alaska, and if so, under what conditions, or whether to continue to prohibit development to protect the area's biological resources. The Refuge is an area rich in fauna, flora, and commercial oil potential. Current law forbids energy leasing in the Refuge.
Date: November 1, 2004
Creator: Corn, M. L.; Gelb, Bernard A. & Baldwin, Pamela
Object Type: Report
System: The UNT Digital Library
Full employment and competition in the Aspen economic model: implications for modeling acts of terrorism. (open access)

Full employment and competition in the Aspen economic model: implications for modeling acts of terrorism.

Acts of terrorism could have a range of broad impacts on an economy, including changes in consumer (or demand) confidence and the ability of productive sectors to respond to changes. As a first step toward a model of terrorism-based impacts, we develop here a model of production and employment that characterizes dynamics in ways useful toward understanding how terrorism-based shocks could propagate through the economy; subsequent models will introduce the role of savings and investment into the economy. We use Aspen, a powerful economic modeling tool developed at Sandia, to demonstrate for validation purposes that a single-firm economy converges to the known monopoly equilibrium price, output, and employment levels, while multiple-firm economies converge toward the competitive equilibria typified by lower prices and higher output and employment. However, we find that competition also leads to churn by consumers seeking lower prices, making it difficult for firms to optimize with respect to wages, prices, and employment levels. Thus, competitive firms generate market ''noise'' in the steady state as they search for prices and employment levels that will maximize profits. In the context of this model, not only could terrorism depress overall consumer confidence and economic activity but terrorist acts could also cause …
Date: November 1, 2004
Creator: Sprigg, James A. & Ehlen, Mark Andrew
Object Type: Report
System: The UNT Digital Library
Technologies for Measuring Flow Rates of Outdoor Air Into HVAC Systems: Some Causes and Suggested Cures for Measurement Errors (open access)

Technologies for Measuring Flow Rates of Outdoor Air Into HVAC Systems: Some Causes and Suggested Cures for Measurement Errors

Although the rate of outdoor air (OA) ventilation has a substantial influence on building energy consumption and occupant health, the available data indicate the outdoor air ventilation rates are poorly controlled in many buildings. Technologies being marketed for real time measurement of the flow rates of outdoor air into HVAC systems should enable better control of OA ventilation. In laboratory research they have studied the performance of these technologies. Sources of measurement errors identified during conduct of this research include: low air speeds; high spatial variability in air speed and direction; large eddies downstream of outdoor air intake louvers; and backwards airflow through a portion of outdoor air dampers. Several suggestions for overcoming these sources of errors were developed including: design and control of the outdoor air intake system to avoid low, hard-to measure, air speeds; use of highly sensitive pressure and velocity sensors; measuring air speeds between blades of louvers, rather than downstream of louvers; smoothing out the airflow between the outdoor air louver and damper through proper louver selection and insertion of components to straighten air flow; and maintaining a pressure drop across the outdoor air damper that exceeds approximately 0.04 IWG (10 Pa).
Date: November 1, 2004
Creator: Fisk, William J.; Faulkner, David & Sullivan, Douglas P.
Object Type: Article
System: The UNT Digital Library
The hydrogen futures simulation model (H2Sim) user's guide. (open access)

The hydrogen futures simulation model (H2Sim) user's guide.

The Hydrogen Futures Simulation Model (H{sub 2}Sim) is a high level, internally consistent, strategic tool for exploring the options of a hydrogen economy. Once the user understands how to use the basic functions, H{sub 2}Sim can be used to examine a wide variety of scenarios, such as testing different options for the hydrogen pathway, altering key assumptions regarding hydrogen production, storage, transportation, and end use costs, and determining the effectiveness of various options on carbon mitigation. This User's Guide explains how to run the model for the first time user.
Date: November 1, 2004
Creator: Kamery, William; Baker, Arnold Barry; Drennen, Thomas E. & Rosthal, Jennifer Elizabeth
Object Type: Report
System: The UNT Digital Library
U.S. Job Creation Due to Nuclear Power Resurgence in The United States — Volumes 1 and 2 (open access)

U.S. Job Creation Due to Nuclear Power Resurgence in The United States — Volumes 1 and 2

The recent revival of interest in nuclear power is causing a reexamination of the role of nuclear power in the United States. This renewed interest has led to questions regarding the capability and capacity of current U.S. industries to support a renewal of nuclear power plant deployment. This study was conducted to provide an initial estimate of jobs to be gained in the U.S. through the repatriation of the nuclear manufacturing industry. In the course of the study, related job categories were also modeled to provide an additional estimate of the potential expansion of existing industries (i.e., plant construction and operations) in conjunction with the repatriation of manufacturing jobs.
Date: November 1, 2004
Creator: Plowman, Catherine M.
Object Type: Report
System: The UNT Digital Library
Cost-Effective Reciprocating Engine Emissions Control and Monitoring for E&P Field and Gathering Engines (open access)

Cost-Effective Reciprocating Engine Emissions Control and Monitoring for E&P Field and Gathering Engines

None
Date: November 1, 2004
Creator: Chapman, Kirby S. & Adriani, Allen
Object Type: Report
System: The UNT Digital Library
Cyclic Polarization Behavior of ASTM A537-Cl.1 Steel in the Vapor Space Above Simulated Waste (open access)

Cyclic Polarization Behavior of ASTM A537-Cl.1 Steel in the Vapor Space Above Simulated Waste

An assessment of the potential degradation mechanisms of Types I and II High-Level Waste (HLW) Tanks determined that pitting corrosion and stress corrosion cracking were the two most significant degradation mechanisms. Specifically, nitrate induced stress corrosion cracking was determined to be the principal degradation mechanism for the primary tank steel of non-stress relieved tanks. Controls on the solution chemistry have been in place to preclude the initiation and propagation of degradation in the tanks. However, recent experience has shown that steel not in contact with the bulk waste solution or slurry, but exposed to the ''vapor space'' above the bulk waste, may be vulnerable to the initiation and propagation of degradation, including pitting and stress corrosion cracking. A program to resolve the issues associated with potential vapor space corrosion is in place. The objective of the program is to develop understanding of vapor space (VSC) and liquid/air interface (LAIC) corrosion to ensure a defensible technical basis to provide accurate corrosion evaluations with regard to vapor space and liquid/air interface corrosion (similar to current evaluations). There are several needs for a technically defensible basis with sufficient understanding to perform these evaluations. These include understanding of the (1) surface chemistry evolution, (2) …
Date: November 1, 2004
Creator: Wiersma, B
Object Type: Report
System: The UNT Digital Library
Decision-Makers' Forum on a Unified Strategy for Nuclear Energy (open access)

Decision-Makers' Forum on a Unified Strategy for Nuclear Energy

An abundant and secure energy supply is critical to our country’s prosperity, and energy supply is now a central issue in global stability and security. Unfortunately, the Unites States continues to steadily increase the fraction of energy it imports from foreign sources. In May 2001, the National Energy Policy noted that this imbalance, "if allowed to continue, will inevitably undermine our economy, our standard of living, and our national security." In addition to these serious impacts, growing concern about air pollution and atmospheric carbon levels hold the potential for global climate change. According to the National Academy of Sciences, the Earth’s surface temperature has risen by about 1 degree Fahrenheit in the past century, with accelerated warming during the past two decades. The current energy supply situation clearly demands coordinated action. Nuclear energy is preeminent in its ability to deliver affordable energy today and meet the growing imperatives for clean air and energy supplies in the future.
Date: November 1, 2004
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Next Generation Nuclear Plant Materials Selection and Qualification Program Plan (open access)

Next Generation Nuclear Plant Materials Selection and Qualification Program Plan

The U.S. Department of Energy (DOE) has selected the Very High Temperature Reactor (VHTR) design for the Next Generation Nuclear Plant (NGNP) Project. The NGNP will demonstrate the use of nuclear power for electricity and hydrogen production without greenhouse gas emissions. The reactor design is a graphite-moderated, helium-cooled, prismatic or pebble bed thermal neutron spectrum reactor with an average reactor outlet temperature of at least 1000 C. The NGNP will use very high burn up, lowenriched uranium, TRISO-Coated fuel in a once-through fuel cycle. The design service life of the NGNP is 60 years.
Date: November 1, 2004
Creator: Hamelin, R. Doug & Hayner, G. O.
Object Type: Report
System: The UNT Digital Library
Estimating Source Terms for Diverse Spent Nuclear Fuel Types (open access)

Estimating Source Terms for Diverse Spent Nuclear Fuel Types

The U.S. Department of Energy (DOE) National Spent Nuclear Fuel Program is responsible for developing a defensible methodology for determining the radionuclide inventory for the DOE spent nuclear fuel (SNF) to be dispositioned at the proposed Monitored Geologic Repository at the Yucca Mountain Site. SNF owned by DOE includes diverse fuels from various experimental, research, and production reactors. These fuels currently reside at several DOE sites, universities, and foreign research reactor sites. Safe storage, transportation, and ultimate disposal of these fuels will require radiological source terms as inputs to safety analyses that support design and licensing of the necessary equipment and facilities. This paper summarizes the methodology developed for estimating radionuclide inventories associated with DOE-owned SNF. The results will support development of design and administrative controls to manage radiological risks and may later be used to demonstrate conformance with repository acceptance criteria.
Date: November 1, 2004
Creator: Carlsen, Brett & Pincock, Layne
Object Type: Article
System: The UNT Digital Library
Beryllium - A Unique Material in Nuclear Applications (open access)

Beryllium - A Unique Material in Nuclear Applications

Beryllium, due to its unique combination of structural, chemical, atomic number, and neutron absorption cross section characteristics, has been used successfully as a neutron reflector for three generations of nuclear test reactors at the Idaho National Engineering and Environmental Laboratory (INEEL). The Advanced Test Reactor (ATR), the largest test reactor in the world, has utilized five successive beryllium neutron reflectors and is scheduled for continued operation with a sixth beryllium reflector. A high radiation environment in a test reactor produces radiation damage and other changes in beryllium. These changes necessitate safety analysis of the beryllium, methods to predict performance, and appropriate surveillances. Other nuclear applications also utilize beryllium. Beryllium, given its unique atomic, physical, and chemical characteristics, is widely used as a “window” for x-rays and gamma rays. Beryllium, intimately mixed with high-energy alpha radiation emitters has been successfully used to produce neutron sources. This paper addresses operational experience and methodologies associated with the use of beryllium in nuclear test reactors and in “windows” for x-rays and gamma rays. Other nuclear applications utilizing beryllium are also discussed.
Date: November 1, 2004
Creator: T., A. Tomberlin
Object Type: Article
System: The UNT Digital Library
Monitoring stream stage, channel profile, and aqueous conductivity with time domain reflectometry (TDR). (open access)

Monitoring stream stage, channel profile, and aqueous conductivity with time domain reflectometry (TDR).

Time domain reflectometry (TDR) operates by propagating a radar frequency electromagnetic pulse down a transmission line while monitoring the reflected signal. As the electromagnetic pulse propagates along the transmission line, it is subject to impedance by the dielectric properties of the media along the transmission line (e.g., air, water, sediment), reflection at dielectric discontinuities (e.g., air-water or water-sediment interface), and attenuation by electrically conductive materials (e.g., salts, clays). Taken together, these characteristics provide a basis for integrated stream monitoring; specifically, concurrent measurement of stream stage, channel profile and aqueous conductivity. Here, we make novel application of TDR within the context of stream monitoring. Efforts toward this goal followed three critical phases. First, a means of extracting the desired stream parameters from measured TDR traces was required. Analysis was complicated by the fact that interface location and aqueous conductivity vary concurrently and multiple interfaces may be present at any time. For this reason a physically based multisection model employing the S11 scatter function and Cole-Cole parameters for dielectric dispersion and loss was developed to analyze acquired TDR traces. Second, we explored the capability of this multisection modeling approach for interpreting TDR data acquired from complex environments, such as encountered in stream …
Date: November 1, 2004
Creator: Brainard, James Robert; Tidwell, Vincent Carroll; Coplen, Amy K.; Ruby, Douglas Scott; Coombs, Jason R.; Wright, Jerome L. et al.
Object Type: Report
System: The UNT Digital Library
Safety Assurance for Irradiating Experiments in the Advanced Test Reactor (open access)

Safety Assurance for Irradiating Experiments in the Advanced Test Reactor

The Advanced Test Reactor (ATR), located at the Idaho National Engineering and Environmental Laboratory (INEEL), was specifically designed to provide a high neutron flux test environment for conducting a variety of experiments. This paper addresses the safety assurance process for two general types of experiments conducted in the ATR facility and how the safety analyses for experiments are related to the ATR safety basis. One type of experiment is more routine and generally represents greater risks; therefore, this type of experiment is addressed in more detail in the ATR safety basis. This allows the individual safety analysis for this type of experiment to be more standardized. The second type of experiment is defined in more general terms in the ATR safety basis and is permitted under more general controls. Therefore, the individual safety analysis for the second type of experiment tends to be more unique and is tailored to each experiment.
Date: November 1, 2004
Creator: Tomberlin, T. A. & Grover, S. B.
Object Type: Article
System: The UNT Digital Library
Patterning quantum dot arrays using DNA replication principles. (open access)

Patterning quantum dot arrays using DNA replication principles.

The convergence of nanoscience and biotechnology has opened the door to the integration of a wide range of biological molecules and processes with synthetic materials and devices. A primary biomolecule of interest has been DNA based upon its role as information storage in living systems, as well as its ability to withstand a wide range of environmental conditions. DNA also offers unique chemistries and interacts with a range of biomolecules, making it an ideal component in biological sensor applications. The primary goal of this project was to develop methods that utilize in vitro DNA synthesis to provide spatial localization of nanocrystal quantum dots (nQDs). To accomplish this goal, three specific technical objectives were addressed: (1) attachment of nQDs to DNA nucleotides, (2) demonstrating the synthesis of nQD-DNA strands in bulk solution, and (3) optimizing the ratio of unlabeled to nQD-labeled nucleotides. DNA nucleotides were successfully attached to nQDs using the biotin-streptavidin linkage. Synthesis of 450-nm long, nQD-coated DNA strands was demonstrated using a DNA template and the polymerase chain reaction (PCR)-based method of DNA amplification. Modifications in the synthesis process and conditions were subsequently used to synthesize 2-{micro}m long linear nQD-DNA assemblies. In the case of the 2-{micro}m structures, both …
Date: November 1, 2004
Creator: Crown, Kevin K. & Bachand, George David
Object Type: Report
System: The UNT Digital Library
Scale formation on Ni-based alloys in simulated solid oxide fuel cell interconnect environments (open access)

Scale formation on Ni-based alloys in simulated solid oxide fuel cell interconnect environments

Recent publications suggest that the environment on the fuel side of the bi-polar stainless steel SOFC interconnects changes the oxidation behavior and morphology of the scale formed on the air side. The U.S. Department of Energy Albany Research Center (ARC), has examined the role of such exposure conditions on advanced nickel base alloys. Alloy formulations developed at ARC and commercial alloys were studied using X-ray diffraction (XRD) and Raman spectroscopy. The electrical property of oxide scales formed on selected alloys was determined in terms of areaspecific resistance (ASR). The corrosion behavior of ARC nickel-based alloys exposed to a dual environment of air/ H2 were compared to those of Crofer 22APU and Haynes 230.
Date: November 1, 2004
Creator: Ziomek-Moroz, Margaret; Cramer, Stephen D.; Holcomb, Gordon R.; Covino, Bernard S., Jr.; Bullard, Sophie J.; Singh, P. (PNNL) et al.
Object Type: Article
System: The UNT Digital Library
Vegetation study in support of the design and optimization of vegetative soil covers, Sandia National Laboratories, Albuquerque, New Mexico. (open access)

Vegetation study in support of the design and optimization of vegetative soil covers, Sandia National Laboratories, Albuquerque, New Mexico.

A vegetation study was conducted in Technical Area 3 at Sandia National Laboratories, Albuquerque, New Mexico in 2003 to assist in the design and optimization of vegetative soil covers for hazardous, radioactive, and mixed waste landfills at Sandia National Laboratories/New Mexico and Kirtland Air Force Base. The objective of the study was to obtain site-specific, vegetative input parameters for the one-dimensional code UNSAT-H and to identify suitable, diverse native plant species for use on vegetative soil covers that will persist indefinitely as a climax ecological community with little or no maintenance. The identification and selection of appropriate native plant species is critical to the proper design and long-term performance of vegetative soil covers. Major emphasis was placed on the acquisition of representative, site-specific vegetation data. Vegetative input parameters measured in the field during this study include root depth, root length density, and percent bare area. Site-specific leaf area index was not obtained in the area because there was no suitable platform to measure leaf area during the 2003 growing season due to severe drought that has persisted in New Mexico since 1999. Regional LAI data was obtained from two unique desert biomes in New Mexico, Sevilletta Wildlife Refuge and Jornada …
Date: November 1, 2004
Creator: Peace, Gerald (Jerry) L.; Goering, Timothy James (GRAM inc., Albuquerque, NM); Knight, Paul J. (Marron and Associates, Albuquerque, NM) & Ashton, Thomas S. (Marron and Associates, Albuquerque, NM)
Object Type: Report
System: The UNT Digital Library
Development of Safety Analysis Codes and Experimental Validation for a Very High Temperature Gas-Cooled Reactor (open access)

Development of Safety Analysis Codes and Experimental Validation for a Very High Temperature Gas-Cooled Reactor

The very high temperature gas-cooled reactors (VHTGRs) are those concepts that have average coolant temperatures above 900 degrees C or operational fuel temperatures above 1250 degrees C. These concepts provide the potential for increased energy conversion efficiency and for high-temperature process heat application in addition to power generation and nuclear hydrogen generation. While all the High Temperature Gas Cooled Reactor (HTGR) concepts have sufficiently high temperatures to support process heat applications, such as desalination and cogeneration, the VHTGR's higher temperatures are suitable for particular applications such as thermochemical hydrogen production. However, the high temperature operation can be detrimental to safety following a loss-of-coolant accident (LOCA) initiated by pipe breaks caused by seismic or other events. Following the loss of coolant through the break and coolant depressurization, air from the containment will enter the core by molecular diffusion and ultimately by natural convection, leading to oxidation of the in-core graphite structures and fuel. The oxidation will release heat and accelerate the heatup of the reactor core. Thus, without any effective countermeasures, a pipe break may lead to significant fuel damage and fission product release. The Idaho National Engineering and Environmental Laboratory (INEEL) has investigated this event for the past three years …
Date: November 1, 2004
Creator: Chang, H. Oh; Davis, Cliff & Moore, Richard
Object Type: Report
System: The UNT Digital Library
NYPA/TH!NK Clean Commute Program Report – Inception Through May 2004 (open access)

NYPA/TH!NK Clean Commute Program Report – Inception Through May 2004

The Clean Commute Program uses TH!NK city electric vehicles from Ford Motor Company’s electric vehicle group, TH!NK Mobility, to demonstrate the feasibility of using electric vehicles for transportation in urban applications. Suburban New York City railroad commuters use the TH!NK city vehicles to commute from their private residences to railroad stations, where they catch commuter trains into New York City. Electric vehicle charging infrastructure for the TH!NK city vehicles is located at the commuters’ private residences as well as seven train stations. Ford leased 97 TH!NK city electric vehicles to commuters from Westchester, Putnam, Rockland, Queens, Nassau, and Suffolk counties for $199 per month per vehicle. The first Clean Commute Program vehicle deliveries occurred late in 2001, with data collection commencing in February 2002. Through May 2004, 24 of the lessees have returned their vehicles to Ford and no longer participate in the Clean Commute Program. Reasons given for returning the vehicles include relocation out of the Program area, change in employment status, change in commuting status, and, in a few cases, dissatisfaction with the vehicle. Additionally, 13 vehicles have been returned to Ford as their leases have completed. In August 2002, Ford announced that it was ceasing production of …
Date: November 1, 2004
Creator: Karner, Don; Francfort, James & Solomon, Randall
Object Type: Report
System: The UNT Digital Library
Development of low coefficient of thermal expansion (CTE) nickel alloys for potential use as interconnects in SOFC (open access)

Development of low coefficient of thermal expansion (CTE) nickel alloys for potential use as interconnects in SOFC

This paper deals with the development of low coefficient of thermal expansion (CTE) nickel-base superalloys for potential use as interconnects for SOFC. Ni-Mo-Cr alloys were formulated with CTE on the order of 12.5 to 13.5 x10-6/°C. The alloys were vacuum induction melted and reduced to sheet via a combination of hot and cold working. Dilatometry was used to measure CTE of the alloys. Oxidation behavior of the alloys at 800°C in dry and moist air is reported. The results are compared to results for Haynes 230 (a commercial Ni-base superalloy) and for Crofer 22APU (a commercial ferritic stainless steel designed specifically for use as an SOFC interconnect).
Date: November 1, 2004
Creator: Alman, David E. & Jablonski, Paul D.
Object Type: Article
System: The UNT Digital Library
AN INNOVATIVE TECHNIQUE FOR THIN FILM INTERFACE TOUGHNESS RESEARCH (open access)

AN INNOVATIVE TECHNIQUE FOR THIN FILM INTERFACE TOUGHNESS RESEARCH

A material configuration of central importance in microelectronics, optoelectronics, and thermal barrier coating technology is a thin or thick film of one material deposited onto a substrate of a different material. Fabrication of such a structure inevitably gives rise to stress in the film due to lattice mismatch, differing coefficients of thermal expansion, chemical reactions, or other physical effects. Therefore, in general, the weakest link in this composite system often resides at the interface between the film and substrate. In order to make multi-layered electronic devices and structural composites with long-term reliability, the fracture behavior of the material interfaces must be known. Unfortunately, none of the state-of-the-art testing methods for evaluating interface fracture toughness is fully conformed to fracture mechanics theory, as is evident from the severe scatter in the existing data and the procedure dependence in film/coating evaluation methods. This project is intended to address the problems associated with this deficiency and offers an innovative testing procedure for the determination of interface fracture toughness applicable to coating materials in general. This new approach and the associated bi-material fracture mechanics development proposed for evaluating interface fracture toughness are described herein. The effort includes development of specimen configuration and related instrumentation …
Date: November 1, 2004
Creator: Wang, J.J.
Object Type: Report
System: The UNT Digital Library
Scaling studies and conceptual experiment designs for NGNP CFD assessment (open access)

Scaling studies and conceptual experiment designs for NGNP CFD assessment

The objective of this report is to document scaling studies and conceptual designs for flow and heat transfer experiments intended to assess CFD codes and their turbulence models proposed for application to prismatic NGNP concepts. The general approach of the project is to develop new benchmark experiments for assessment in parallel with CFD and coupled CFD/systems code calculations for the same geometry. Two aspects of the complex flow in an NGNP are being addressed: (1) flow and thermal mixing in the lower plenum ("hot streaking" issue) and (2) turbulence and resulting temperature distributions in reactor cooling channels ("hot channel" issue). Current prismatic NGNP concepts are being examined to identify their proposed flow conditions and geometries over the range from normal operation to decay heat removal in a pressurized cooldown. Approximate analyses have been applied to determine key non-dimensional parameters and their magnitudes over this operating range. For normal operation, the flow in the coolant channels can be considered to be dominant turbulent forced convection with slight transverse property variation. In a pressurized cooldown (LOFA) simulation, the flow quickly becomes laminar with some possible buoyancy influences. The flow in the lower plenum can locally be considered to be a situation of …
Date: November 1, 2004
Creator: McEligot, D. M. & McCreery, G. E.
Object Type: Report
System: The UNT Digital Library
MEA Component Durability (open access)

MEA Component Durability

Membrane electrode assembly (MEA) lifetime of greater than 40,000 hours remains a goal of the fuel cell industry. However, there is a lack of fundamental understanding of the mechanisms of MEA degradation. Specifically, the relationship between component physical property changes and MEA performance decay has not been established. We report preliminary data relating changes in gas diffusion layer (GDL) physical properties to fuel cell performance decay.
Date: November 1, 2004
Creator: Frisk, J. W.; Hicks, M.T.; Atanasoski, R. T.; Boand, W. M.; Schmoeckel, A. K. & Kurkowski, M. J.
Object Type: Article
System: The UNT Digital Library
Year 2 Biomass Utilization: Final Technical Report (open access)

Year 2 Biomass Utilization: Final Technical Report

This Energy & Environmental Research Center (EERC) Year 2 Biomass Utilization Final Technical Report summarizes multiple projects in biopower or bioenergy, transportation biofuels, and bioproducts. A prototype of a novel advanced power system, termed the high-temperature air furnace (HITAF), was tested for performance while converting biomass and coal blends to energy. Three biomass fuels--wood residue or hog fuel, corn stover, and switchgrass--and Wyoming subbituminous coal were acquired for combustion tests in the 3-million-Btu/hr system. Blend levels were 20% biomass--80% coal on a heat basis. Hog fuel was prepared for the upcoming combustion test by air-drying and processing through a hammer mill and screen. A K-Tron biomass feeder capable of operating in both gravimetric and volumetric modes was selected as the HITAF feed system. Two oxide dispersion-strengthened (ODS) alloys that would be used in the HITAF high-temperature heat exchanger were tested for slag corrosion rates. An alumina layer formed on one particular alloy, which was more corrosion-resistant than a chromia layer that formed on the other alloy. Research activities were completed in the development of an atmospheric pressure, fluidized-bed pyrolysis-type system called the controlled spontaneous reactor (CSR), which is used to process and condition biomass. Tree trimmings were physically and chemically …
Date: November 1, 2004
Creator: Zygarlicke, Christopher J.
Object Type: Report
System: The UNT Digital Library