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Assessment of Void Swelling in Austenitic Stainless Steel Core Internals. (open access)

Assessment of Void Swelling in Austenitic Stainless Steel Core Internals.

As many pressurized water reactors (PWRs) age and life extension of the aged plants is considered, void swelling behavior of austenitic stainless steel (SS) core internals has become the subject of increasing attention. In this report, the available database on void swelling and density change of austenitic SSs was critically reviewed. Irradiation conditions, test procedures, and microstructural characteristics were carefully examined, and key factors that are important to determine the relevance of the database to PWR conditions were evaluated. Most swelling data were obtained from steels irradiated in fast breeder reactors at temperatures >385 C and at dose rates that are orders of magnitude higher than PWR dose rates. Even for a given irradiation temperature and given steel, the integral effects of dose and dose rate on void swelling should not be separated. It is incorrect to extrapolate swelling data on the basis of 'progressive compounded multiplication' of separate effects of factors such as dose, dose rate, temperature, steel composition, and fabrication procedure. Therefore, the fast reactor data should not be extrapolated to determine credible void swelling behavior for PWR end-of-life (EOL) or life-extension conditions. Although the void swelling data extracted from fast reactor studies is extensive and conclusive, only …
Date: January 31, 2006
Creator: Chung, H. M. & Technology, Energy
Object Type: Report
System: The UNT Digital Library
Hybrid Electric Power Train and Control Strategies Automotive Technology Education (GATE) Program (open access)

Hybrid Electric Power Train and Control Strategies Automotive Technology Education (GATE) Program

Plug-in hybrid electric vehicles (PHEV) offer societal benefits through their ability to displace the use of petroleum fuels. Petroleum fuels represent a polluting and politically destabilizing energy carrier. PHEV technologies can move transportation away from petroleum fuel sources by enabling domestically generated electricity and liquids bio-fuels to serve as a carrier for transportation energy. Additionally, the All-Electric-Range (AER) offered by PHEVs can significantly reduce demand for expensive and polluting liquid fuels. The GATE funding received during the 1998 through 2004 funding cycle by the UC Davis Hybrid Electric Vehicle Center (HEVC) was used to advance and train researchers in PHEV technologies. GATE funding was used to construct a rigorous PHEV curriculum, provide financial support for HEVC researchers, and provide material support for research efforts. A rigorous curriculum was developed through the UC Davis Mechanical and Aeronautical Engineering Department to train HEVC researchers. Students' research benefited from this course work by advancing the graduate student researchers' understanding of key PHEV design considerations. GATE support assisted HEVC researchers in authoring technical articles and producing patents. By supporting HEVC researchers multiple Master's theses were written as well as journal articles and publications. The topics from these publications include Continuously Variable Transmission control strategies …
Date: May 31, 2006
Creator: Frank, Andrew
Object Type: Report
System: The UNT Digital Library
Mixed Ionic and Electonic Conductors for Hydrogen Generation and Separation: A New Approach (open access)

Mixed Ionic and Electonic Conductors for Hydrogen Generation and Separation: A New Approach

Composite mixed conductors comprising one electronic conducting phase, and one ionic conducting phase (MIECs) have been developed in this work. Such MIECs have applications in generating and separating hydrogen from hydrocarbon fuels at high process rates and high purities. The ionic conducting phase comprises of rare-earth doped ceria and the electronic conducting phase of rare-earth doped strontium titanate. These compositions are ideally suited for the hydrogen separation application. In the process studied in this project, steam at high temperatures is fed to one side of the MIEC membrane and hydrocarbon fuel or reformed hydrocarbon fuel to the other side of the membrane. Oxygen is transported from the steam side to the fuel side down the electrochemical potential gradient thereby enriching the steam side flow in hydrogen. The remnant water vapor can then be condensed to obtain high purity hydrogen. In this work we have shown that two-phase MIECs comprising rare-earth ceria as the ionic conductor and doped-strontium titanate as the electronic conductor are stable in the operating environment of the MIEC. Further, no adverse reaction products are formed when these phases are in contact at elevated temperatures. The composite MIECs have been characterized using a transient electrical conductivity relaxation technique …
Date: December 31, 2006
Creator: Gopalan, Srikanth
Object Type: Report
System: The UNT Digital Library
Radkowsky Thorium Fuel Project (open access)

Radkowsky Thorium Fuel Project

In the early/mid 1990’s Prof. Alvin Radkowsky, former chief scientist of the U.S. Naval Reactors program, proposed an alternate fuel concept employing thorium-based fuel for use in existing/next generation pressurized water reactors (PWRs). The concept was based on the use of a 'seed-blanket-unit' (SBU) that was a one-for-one replacement for a standard PWR assembly with a uranium-based central 'driver' zone, surrounded by a 'blanket' zone containing uranium and thorium. Therefore, the SBU could be retrofit without significant modifications into existing/next generation PWRs. The objective was to improve the proliferation and waste characteristics of the current once-through fuel cycle. The objective of a series of projects funded by the Initiatives for Proliferation Prevention program of the U.S. Department of Energy (DOE-IPP) - BNL-T2-0074,a,b-RU 'Radkowsky Thorium Fuel (RTF) Concept' - was to explore the characteristics and potential of this concept. The work was performed under several BNL CRADAs (BNL-C-96-02 and BNL-C-98-15) with the Radkowsky Thorium Power Corp./Thorium Power Inc. and utilized the technical and experimental capabilities in the Former Soviet Union (FSU) to explore the potential of this concept for implementation in Russian pressurized water reactors (VVERs), and where possible, also generate data that could be used for design and licensing of …
Date: December 31, 2006
Creator: Todosow, Michael
Object Type: Report
System: The UNT Digital Library
Countercurrent Process for Lignin Separation from Biomass Matrix (open access)

Countercurrent Process for Lignin Separation from Biomass Matrix

The overall goal of the project was to test the concept of using a twin-screw extruder to conduct autohydrolysis pretreatment of wheat straw in countercurrent fashion, demonstrate in situ solid/liquid separation, and produce a low-lignin cellulose product using ethanol as an extractant. The resultant solid product is suitable for sugar production through enzymatic hydrolysis and for pulp applications. Pilot-scale equipment was used to successfully demonstrate the process both for sugar and pulp applications.
Date: March 31, 2006
Creator: Kadam, Kiran & Lehrburger, Ed
Object Type: Report
System: The UNT Digital Library
Numerical Modeling of Impact Initiation of High Explosives (open access)

Numerical Modeling of Impact Initiation of High Explosives

We performed continuum mechanics simulations to examine the behavior of energetic materials in Ballistic Chamber Impact (BIC) experiments, using an Arbitrary Lagrangian-Eulerian code (ALE3D). Our simulations revealed that interface friction plays an important role in inducing the formation of shear bands, which result in 'hot spots' for ignition. The temperature localization during BIC impact was found to be significant in materials with high yield strength. In those materials, there are multiple locations inside shear bands can achieve temperatures exceeding the threshold temperature for reaction. In addition, we investigated the relevant parameters influencing the pressure profile of a BIC test by numerical analysis from a simple phenomenological model. To our surprise, we found that the peaks of BIC pressure profiles not only can be a result of multi-center chemical reactions, but can also arise from factors associated apparatus configuration.
Date: May 31, 2006
Creator: Wu, C J; Piggott, T; Yoh, J & Reaugh, J
Object Type: Report
System: The UNT Digital Library
317/319 phytoremediation site monitoring report - 2005 growing season. (open access)

317/319 phytoremediation site monitoring report - 2005 growing season.

In 1999, Argonne National Laboratory (ANL) designed and installed a series of engineered plantings consisting of a vegetative cover system and approximately 800 hybrid poplars and willows rooting at various predetermined depths. The plants were installed using various methods including Applied Natural Science's TreeWell{reg_sign} system. The goal of the installation was to protect downgradient surface and groundwater by hydraulic control of the contaminated plume by intercepting the contaminated groundwater with the tree roots, removing moisture from the upgradient soil area, reducing water infiltration, preventing soil erosion, degrading and/or transpiring the residual volatile organic compounds (VOCs), and removing tritium from the subsoil and groundwater. This report presents the results of the monitoring activities conducted by Argonne's Energy Systems Division (ES) in the growing season of 2005. Monitoring of the planted trees began soon after the trees were installed in 1999 and has been conducted every summer since then. As the trees grew and consolidated their growth into the contaminated soil and groundwater, their exposure to the contaminants was progressively shown through tissue sampling. However, as trees grow larger, some of the findings obtained in the early years when trees were much smaller may not hold true now and need to be …
Date: March 31, 2006
Creator: Negri, M. C.; Gopalakrishnan, G. & Systems, Energy
Object Type: Report
System: The UNT Digital Library
Project Work Plan: Hanford 100-D Area Treatability Demonstration - In Situ Biostimulation for Reducing Barrier (open access)

Project Work Plan: Hanford 100-D Area Treatability Demonstration - In Situ Biostimulation for Reducing Barrier

This work plan supports a new, integrated approach to accelerate cleanup of chromium in the Hanford 100 Areas. This new approach will provide supplemental treatment upgradient of the ISRM barrier by directly treating chromium and other oxidizing species in groundwater (i.e., nitrate and dissolved oxygen), thereby increasing the longevity of the ISRM barrier and protecting the ecological receptors and human health at the river boundary.
Date: May 31, 2006
Creator: Fruchter, Jonathan S.; Truex, Michael J.; Vermeul, Vince R. & Long, Philip E.
Object Type: Report
System: The UNT Digital Library
Elastic electron scattering from formic acid (open access)

Elastic electron scattering from formic acid

Following our earlier study on the dynamics of low energy electron attachment to formic acid, we report the results of elastic low-energy electron collisions with formic acid. Momentum transfer and angular differential cross sections were obtained by performing fixed-nuclei calculations employing the complex Kohn variational method. We make a brief description of the technique used to account for the polar nature of this polyatomic target and compare our results with available experimental data.
Date: July 31, 2006
Creator: Trevisan, Cynthia S.; Orel, Ann E. & Rescigno, Thomas N.
Object Type: Article
System: The UNT Digital Library
Individual Particle Analysis of Ambient PM 2.5 Using Advanced Electron Microscopy Techniques (open access)

Individual Particle Analysis of Ambient PM 2.5 Using Advanced Electron Microscopy Techniques

The overall goal of this project was to demonstrate a combination of advanced electron microscopy techniques that can be effectively used to identify and characterize individual particles and their sources. Specific techniques to be used include high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM), STEM energy dispersive X-ray spectrometry (EDX), and energy-filtered TEM (EFTEM). A series of ambient PM{sub 2.5} samples were collected in communities in southwestern Detroit, MI (close to multiple combustion sources) and Steubenville, OH (close to several coal fired utility boilers). High-resolution TEM (HRTEM) -imaging showed a series of nano-metal particles including transition metals and elemental composition of individual particles in detail. Submicron and nano-particles with Al, Fe, Ti, Ca, U, V, Cr, Si, Ba, Mn, Ni, K and S were observed and characterized from the samples. Among the identified nano-particles, combinations of Al, Fe, Si, Ca and Ti nano-particles embedded in carbonaceous particles were observed most frequently. These particles showed very similar characteristics of ultrafine coal fly ash particles that were previously reported. By utilizing HAADF-STEM, STEM-EDX, and EF-TEM, this investigation was able to gain information on the size, morphology, structure, and elemental composition of individual nano-particles collected in Detroit and Steubenville. The results showed …
Date: December 31, 2006
Creator: Keeler, Gerald J. & Morishita, Masako
Object Type: Report
System: The UNT Digital Library
A Top to Bottom Lithospheric Study of Africa and Arabia (open access)

A Top to Bottom Lithospheric Study of Africa and Arabia

We study the lithospheric structure of Africa, Arabia and adjacent oceanic regions with fundamental-mode surface waves over a wide period range. Including short period group velocities allows us to examine shallower features than previous studies of the whole continent. In the process, we have developed a crustal thickness map of Africa. Main features include crustal thickness increases under the West African, Congo, and Kalahari cratons. We find crustal thinning under Mesozoic and Cenozoic rifts, including the Benue Trough, Red Sea, and East, Central, and West African rift systems. Crustal shear wave velocities are generally faster in oceanic regions and cratons, and slower in more recent crust and in active and formerly active orogenic regions. Deeper structure, related to the thickness of cratons and modern rifting, is generally consistent with previous work. Under cratons we find thick lithosphere and fast upper mantle velocities, while under rifts we find thinned lithosphere and slower upper mantle velocities. There are no consistent effects in areas classified as hotspots, indicating that there seem to be numerous origins for these features. Finally, it appears that the African Superswell has had a significantly different impact in the north and the south, indicating specifics of the feature (temperature, …
Date: October 31, 2006
Creator: Pasyanos, M
Object Type: Article
System: The UNT Digital Library
Amended Silicated for Mercury Control (open access)

Amended Silicated for Mercury Control

Amended Silicates{trademark}, a powdered, noncarbon mercury-control sorbent, was tested at Duke Energy's Miami Fort Station, Unit 6 during the first quarter of 2006. Unit 6 is a 175-MW boiler with a cold-side electrostatic precipitator (ESP). The plant burns run-of-the-river eastern bituminous coal with typical ash contents ranging from 8-15% and sulfur contents from 1.6-2.6% on an as-received basis. The performance of the Amended Silicates sorbent was compared with that for powdered activated carbon (PAC). The trial began with a period of baseline monitoring during which no sorbent was injected. Sampling during this and subsequent periods indicated mercury capture by the native fly ash was less than 10%. After the baseline period, Amended Silicates sorbent was injected at several different ratios, followed by a 30-day trial at a fixed injection ratio of 5-6 lb/MMACF. After this period, PAC was injected to provide a comparison. Approximately 40% mercury control was achieved for both the Amended Silicates sorbent and PAC at injection ratios of 5-6 lbs/MMACF. Higher injection ratios did not achieve significantly increased removal. Similar removal efficiencies have been reported for PAC injection trials at other plants with cold-side ESPs, most notably for plants using medium to high sulfur coal. Sorbent injection …
Date: December 31, 2006
Creator: Butz, James; Broderick, Thomas & Turchi, Craig
Object Type: Report
System: The UNT Digital Library
Development of a Performance-Based Industrial Energy Efficiency Indicator for Corn Refining Plants. (open access)

Development of a Performance-Based Industrial Energy Efficiency Indicator for Corn Refining Plants.

Organizations that implement strategic energy management programs have the potential to achieve sustained energy savings if the programs are carried out properly. A key opportunity for achieving energy savings that plant managers can take is to determine an appropriate level of energy performance by comparing their plant's performance with that of similar plants in the same industry. Manufacturing facilities can set energy efficiency targets by using performance-based indicators. The U.S. Environmental Protection Agency (EPA), through its ENERGY STAR{reg_sign} program, has been developing plant energy performance indicators (EPIs) to encourage a variety of U.S. industries to use energy more efficiently. This report describes work with the corn refining industry to provide a plant-level indicator of energy efficiency for facilities that produce a variety of products--including corn starch, corn oil, animal feed, corn sweeteners, and ethanol--for the paper, food, beverage, and other industries in the United States. Consideration is given to the role that performance-based indicators play in motivating change; the steps needed to develop indicators, including interacting with an industry to secure adequate data for an indicator; and the actual application and use of an indicator when complete. How indicators are employed in the EPA's efforts to encourage industries to voluntarily …
Date: July 31, 2006
Creator: Boyd, G. A. & Sciences, Decision and Information
Object Type: Report
System: The UNT Digital Library
Sorbent Injection for Small ESP Mercury Control in Low Sulfur Eastern Bituminous Coal Flue Gas (open access)

Sorbent Injection for Small ESP Mercury Control in Low Sulfur Eastern Bituminous Coal Flue Gas

This project Final Report is submitted to the U.S. Department of Energy (DOE) as part of Cooperative Agreement DE-FC26-03NT41987, 'Sorbent Injection for Small ESP Mercury Control in Low Sulfur Eastern Bituminous Coal Flue Gas.' Sorbent injection technology is targeted as the primary mercury control process on plants burning low/medium sulfur bituminous coals equipped with ESP and ESP/FGD systems. About 70% of the ESPs used in the utility industry have SCAs less than 300 ft2/1000 acfm. Prior to this test program, previous sorbent injection tests had focused on large-SCA ESPs. This DOE-NETL program was designed to generate data to evaluate the performance and economic feasibility of sorbent injection for mercury control at power plants that fire bituminous coal and are configured with small-sized electrostatic precipitators and/or an ESP-flue gas desulfurization (FGD) configuration. EPRI and Southern Company were co-funders for the test program. Southern Company and Reliant Energy provided host sites for testing and technical input to the project. URS Group was the prime contractor to NETL. ADA-ES and Apogee Scientific Inc. were sub-contractors to URS and was responsible for all aspects of the sorbent injection systems design, installation and operation at the different host sites. Full-scale sorbent injection for mercury control …
Date: December 31, 2006
Creator: Richardson, Carl; Dombrowski, Katherine & Orr, Douglas
Object Type: Report
System: The UNT Digital Library
Separation of Fischer-Tropsch Wax Products from Ultrafine Iron Catalyst Particles (open access)

Separation of Fischer-Tropsch Wax Products from Ultrafine Iron Catalyst Particles

A fundamental filtration study was started to investigate the separation of Fischer-Tropsch Synthesis (FTS) liquids from iron-based catalyst particles. Slurry-phase FTS in slurry bubble column reactor systems is the preferred mode of operation since the reaction is highly exothermic. Consequently, heavy wax products in one approach may be separated from catalyst particles before being removed from the reactor system. Achieving an efficient wax product separation from iron-based catalysts is one of the most challenging technical problems associated with slurry-phase iron-based FTS and is a key factor for optimizing operating costs. The separation problem is further compounded by attrition of iron catalyst particles and the formation of ultra-fine particles.
Date: December 31, 2006
Creator: Sarkar, Amitava; Neathery, James K. & Davis, Burtron H.
Object Type: Report
System: The UNT Digital Library
Heavy Truck Clean Diesel Cooperative Research Program (open access)

Heavy Truck Clean Diesel Cooperative Research Program

This report is the final report for the Department of Energy on the Heavy Truck Engine Program (Contract No. DE-FC05-00OR22806) also known as Heavy Truck Clean Diesel (HTCD) Program. Originally, this was scoped to be a $38M project over 5 years, to be 50/50 co-funded by DOE and Caterpillar. The program started in June 2000. During the program the timeline was extended to a sixth year. The program completed in December 2006. The program goal was to develop and demonstrate the technologies required to enable compliance with the 2007 and 2010 (0.2g/bhph NOx, 0.01g/bhph PM) on-highway emission standards for Heavy Duty Trucks in the US with improvements in fuel efficiency compared to today's engines. Thermal efficiency improvement from a baseline of 43% to 50% was targeted.
Date: December 31, 2006
Creator: Milam, David
Object Type: Report
System: The UNT Digital Library
Improved Oil Recovery from Upper Jurassic Smackover Carbonates through the Application of Advanced Technologies at Womack Hill Oil Field, Choctaw and Clarke Counties, Eastern Gulf Costal Plain (open access)

Improved Oil Recovery from Upper Jurassic Smackover Carbonates through the Application of Advanced Technologies at Womack Hill Oil Field, Choctaw and Clarke Counties, Eastern Gulf Costal Plain

Pruet Production Co. and the Center for Sedimentary Basin Studies at the University of Alabama, in cooperation with Texas A&M University, Mississippi State University, University of Mississippi, and Wayne Stafford and Associates proposed a three-phase, focused, comprehensive, integrated and multidisciplinary study of Upper Jurassic Smackover carbonates (Class II Reservoir), involving reservoir characterization and 3-D modeling (Phase I) and a field demonstration project (Phases II and III) at Womack Hill Field Unit, Choctaw and Clarke Counties, Alabama, eastern Gulf Coastal Plain. Phase I of the project has been completed. The principal objectives of the project are: increasing the productivity and profitability of the Womack Hill Field Unit, thereby extending the economic life of this Class II Reservoir and transferring effectively and in a timely manner the knowledge gained and technology developed from this project to producers who are operating other domestic fields with Class II Reservoirs. The major tasks of the project included reservoir characterization, recovery technology analysis, recovery technology evaluation, and the decision to implement a demonstration project. Reservoir characterization consisted of geoscientific reservoir characterization, petrophysical and engineering property characterization, microbial characterization, and integration of the characterization data. Recovery technology analysis included 3-D geologic modeling, reservoir simulation, and microbial core …
Date: May 31, 2006
Creator: Mancini, Ernest A.
Object Type: Report
System: The UNT Digital Library
Commercial Demonstration of the Manufactured Aggregate Processing Technology Utilizing Spray Dryer Ash (open access)

Commercial Demonstration of the Manufactured Aggregate Processing Technology Utilizing Spray Dryer Ash

Universal Aggregates LLC (UA) was awarded a cost sharing Co-operative Agreement from the Department of Energy (DOE) through the Power Plant Improvement Initiative Program (PPII) to design, construct and operate a lightweight aggregate manufacturing plant at the Birchwood Power Facility in King George, Virginia in October 2001. The Agreement was signed in November 2002. The installation and start-up expenses for the Birchwood Aggregate Facility are $19.5 million. The DOE share is $7.2 million (37%) and the UA share is $12.3 million (63%). The original project team consists of UA, SynAggs, LLC, CONSOL Energy Inc. and P. J. Dick, Inc. Using 115,000 ton per year of spray dryer ash (SDA), a dry FGD by-product from the power station, UA will produce 167,000 tons of manufactured lightweight aggregate for use in production of concrete masonry units (CMU). Manufacturing aggregate from FGD by-products can provide an economical high-volume use and substantially expand market for FGD by-products. Most of the FGD by-products are currently disposed of in landfills. Construction of the Birchwood Aggregate Facility was completed in March 2004. Operation startup was begun in April 2004. Plant Integration was initiated in December 2004. Integration includes mixing, extrusion, curing, crushing and screening. Lightweight aggregates with …
Date: December 31, 2006
Creator: Wu, Milton & Yuran, Paul
Object Type: Report
System: The UNT Digital Library
Exploring Metric Symmetry (open access)

Exploring Metric Symmetry

Relatively minor perturbations to a crystal structure can in some cases result in apparently large changes in symmetry. Changes in space group or even lattice can be induced by heavy metal or halide soaking (Dauter et al, 2001), flash freezing (Skrzypczak-Jankun et al, 1996), and Se-Met substitution (Poulsen et al, 2001). Relations between various space groups and lattices can provide insight in the underlying structural causes for the symmetry or lattice transformations. Furthermore, these relations can be useful in understanding twinning and how to efficiently solve two different but related crystal structures. Although (pseudo) symmetric properties of a certain combination of unit cell parameters and a space group are immediately obvious (such as a pseudo four-fold axis if a is approximately equal to b in an orthorhombic space group), other relations (e.g. Lehtio, et al, 2005) that are less obvious might be crucial to the understanding and detection of certain idiosyncrasies of experimental data. We have developed a set of tools that allows straightforward exploration of possible metric symmetry relations given unit cell parameters and a space group. The new iotbx.explore{_}metric{_}symmetry command produces an overview of the various relations between several possible point groups for a given lattice. Methods for …
Date: July 31, 2006
Creator: Zwart, P. H.; Grosse-Kunstleve, R. W. & Adams, P. D.
Object Type: Report
System: The UNT Digital Library
Summary of DOE/PERF water program review. (open access)

Summary of DOE/PERF water program review.

For many years, the U.S. Department of Energy (DOE) has supported and sponsored various types of water research relating to the oil and gas industry through its Office of Fossil Energy and its National Energy Technology Laboratory (NETL). In early 2005, the Petroleum Environmental Research Forum (PERF) submitted a proposal to DOE for funding an upcoming PERF meeting that would feature water research in the petroleum industry. PERF is a nonprofit organization created in 1986 to provide a stimulus to and a forum for the collection, exchange, and analysis of research information related to the development of technology concerning the petroleum industry, and a mechanism for establishing joint research projects in that field. Additional information on PERF can be accessed at http://www.perf.org. DOE agreed to provide funding to hold a review of its water research program in conjunction with the fall 2005 PERF meeting. Argonne National Laboratory (Argonne) was asked to coordinate and host the meeting, which was referred to as the DOE/PERF Water Program Review. The program review was held on November 1-4, 2005, in Annapolis, Maryland, at the Historic Inns of Annapolis. The purpose of the program review was to provide a forum for sharing information, reviewing current …
Date: January 31, 2006
Creator: Veil, J.; Gasper, J.; Puder, M.; Leath, P. & Division, Environmental Science
Object Type: Report
System: The UNT Digital Library
Enhanced Activity of Nanocrystalline Zeolites for Selective Catalytic Reduction of NOx (open access)

Enhanced Activity of Nanocrystalline Zeolites for Selective Catalytic Reduction of NOx

Nanocrystalline zeolites with discrete crystal sizes of less than 100 nm have different properties relative to zeolites with larger crystal sizes. Nanocrystalline zeolites have improved mass transfer properties and very large internal and external surface areas that can be exploited for many different applications. The additional external surface active sites and the improved mass transfer properties of nanocrystalline zeolites offer significant advantages for selective catalytic reduction (SCR) catalysis with ammonia as a reductant in coal-fired power plants relative to current zeolite based SCR catalysts. Nanocrystalline NaY was synthesized with a crystal size of 15-20 nm and was thoroughly characterized using x-ray diffraction, electron paramagnetic resonance spectroscopy, nitrogen adsorption isotherms and Fourier Transform Infrared (FT-IR) spectroscopy. Copper ions were exchanged into nanocrystalline NaY to increase the catalytic activity. The reactions of nitrogen dioxides (NO{sub x}) and ammonia (NH{sub 3}) on nanocrystalline NaY and CuY were investigated using FT-IR spectroscopy. Significant conversion of NO{sub 2} was observed at room temperature in the presence of NH{sub 3} as monitored by FT-IR spectroscopy. Copper-exchanged nanocrystalline NaY was more active for NO{sub 2} reduction with NH{sub 3} relative to nanocrystalline NaY.
Date: December 31, 2006
Creator: Larson, Sarah C. & Grassian, Vicki H.
Object Type: Report
System: The UNT Digital Library
Electrically Conductive, Corrosion-Resistant Coatings Through Defect Chemistry for Metallic Interconnects (open access)

Electrically Conductive, Corrosion-Resistant Coatings Through Defect Chemistry for Metallic Interconnects

The principal objective of this work was to develop oxidation protective coatings for metallic interconnect based on a defect chemistry approach. It was reasoned that the effectiveness of a coating is dictated by oxygen permeation kinetics; the slower the permeation kinetics, the better the protection. All protective coating materials investigated to date are either perovskites or spinels containing metals exhibiting multiple valence states (Co, Fe, Mn, Cr, etc.). As a result, all of these oxides exhibit a reasonable level of electronic conductivity; typically at least about {approx}0.05 S/cm at 800 C. For a 5 micron coating, this equates to a maximum {approx}0.025 {Omega}cm{sup 2} area specific resistance due to the coating. This suggests that the coating should be based on oxygen ion conductivity (the lower the better) and not on electronic conductivity. Measurements of ionic conductivity of prospective coating materials were conducted using Hebb-Wagner method. It was demonstrated that special precautions need to be taken to measure oxygen ion conductivity in these materials with very low oxygen vacancy concentration. A model for oxidation under a protective coating is presented. Defect chemistry based approach was developed such that by suitably doping, oxygen vacancy concentration was suppressed, thus suppressing oxygen ion transport …
Date: December 31, 2006
Creator: Virkar, Anil V.
Object Type: Report
System: The UNT Digital Library
Clean Coal Diesel Demonstration Project (open access)

Clean Coal Diesel Demonstration Project

A Clean Coal Diesel project was undertaken to demonstrate a new Clean Coal Technology that offers technical, economic and environmental advantages over conventional power generating methods. This innovative technology (developed to the prototype stage in an earlier DOE project completed in 1992) enables utilization of pre-processed clean coal fuel in large-bore, medium-speed, diesel engines. The diesel engines are conventional modern engines in many respects, except they are specially fitted with hardened parts to be compatible with the traces of abrasive ash in the coal-slurry fuel. Industrial and Municipal power generating applications in the 10 to 100 megawatt size range are the target applications. There are hundreds of such reciprocating engine power-plants operating throughout the world today on natural gas and/or heavy fuel oil.
Date: October 31, 2006
Creator: Wilson, Robert
Object Type: Report
System: The UNT Digital Library
The California Greenhouse Gas Initiative and Its Implications to the Automotive Industry (open access)

The California Greenhouse Gas Initiative and Its Implications to the Automotive Industry

CAR undertook this investigation to better understand the costs and challenges of a local (state) regulation necessitating the implementation of alternative or advanced powertrain technology. CAR will attempt to add insight into the challenges that local regulations present to the automotive industry, and to contribute further to the discussion of how advanced powertrain technology may be used to meet such regulation. Any local law that (directly or indirectly) affects light duty motor vehicle fuel economy creates what in effect is a specialty market for powertrain technology. As such these small markets present significant challenges for automotive manufacturers. First, a small market with unique standards presents significant challenges to an industry that has sustained growth by relying on large volumes to achieve scale economies and deliver products at a cost acceptable to the consumer. Further, the challenges of the additional technology make it likely that any powertrain capable of meeting the stringent emissions standards will include costly additional components, and thus will be more costly to manufacture. It is likely that manufacturers would consider the following actions as steps to deliver products to meet the pending California regulatory requirements anticipated as a result of prior California legislation: (1) Substituting more fuel …
Date: May 31, 2006
Creator: Smith, B. C.; Miller, R. T. & Research, Center for Automotive
Object Type: Report
System: The UNT Digital Library