Energy Star Concepts for Highway Vehicles (open access)

Energy Star Concepts for Highway Vehicles

The authors of this report, under the sponsorship of the U.S. Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy (EERE) Weatherization and Intergovernmental Program, have investigated the possible application of Energy Star ratings to passenger cars and light trucks. This study establishes a framework for formulating and evaluating Energy Star rating methods that is comprised of energy- and environmental-based metrics, potential vehicle classification systems, vehicle technology factors, and vehicle selection criteria. The study tests several concepts and Energy Star rating methods using model-year 2000 vehicle data--a spreadsheet model has been developed to facilitate these analyses. This study tests two primary types of rating systems: (1) an outcome-based system that rates vehicles based on fuel economy, GHG emissions, and oil use and (2) a technology-based system that rates vehicles based on the energy-saving technologies they use. Rating methods were evaluated based on their ability to select vehicles with high fuel economy, low GHG emissions, and low oil use while preserving a full range of service (size and acceleration) and body style choice. This study concludes that an Energy Star rating for passenger cars and light trucks is feasible and that several methods could be used to achieve reasonable …
Date: June 24, 2003
Creator: Greene, D. L.
Object Type: Report
System: The UNT Digital Library
Railroad and Locomotive Technology Roadmap. (open access)

Railroad and Locomotive Technology Roadmap.

Railroads are important to the U.S. economy. They transport freight efficiently, requiring less energy and emitting fewer pollutants than other modes of surface transportation. While the railroad industry has steadily improved its fuel efficiency--by 16% over the last decade--more can, and needs to, be done. The ability of locomotive manufacturers to conduct research into fuel efficiency and emissions reduction is limited by the small number of locomotives manufactured annually. Each year for the last five years, the two North American locomotive manufacturers--General Electric Transportation Systems and the Electro-Motive Division of General Motors--have together sold about 800 locomotives in the United States. With such a small number of units over which research costs can be spread, outside help is needed to investigate all possible ways to reduce fuel usage and emissions. Because fuel costs represent a significant portion of the total operating costs of a railroad, fuel efficiency has always been an important factor in the design of locomotives and in the operations of a railroad. However, fuel efficiency has recently become even more critical with the introduction of strict emission standards by the U.S. Environmental Protection Agency, to be implemented in stages (Tiers 0, 1, and 2) between 2000 and …
Date: February 24, 2003
Creator: Stodolsky, F.; Gaines, L. & Systems, Energy
Object Type: Report
System: The UNT Digital Library
The Impact of Humidity, Temperature and Ultraviolet Light on the Near-Field Environmental Fate of Pinacolyl Alcohol, Methyl Iodide, Methylphosphonic Dichloride (DCMP) and Thionyl Chloride Using an Environmental Wind Tunnel (open access)

The Impact of Humidity, Temperature and Ultraviolet Light on the Near-Field Environmental Fate of Pinacolyl Alcohol, Methyl Iodide, Methylphosphonic Dichloride (DCMP) and Thionyl Chloride Using an Environmental Wind Tunnel

Understanding the near-field fate of parent chemicals and their decay products in the atmosphere provides essential information for the development of remote chemical sensors. To elucidate the near-field fate of candidate chemical signatures, selected gas phase compounds were introduced into atmospheres of varying humidity, temperature and incident light flux. These atmospheres were maintained in an environmental wind tunnel for periods typical of near-field transport scenarios. The range of humidity and temperature into which the compounds were emitted encompassed arid, temperate, and tropical values. Simulated sunlight exposure was used to evaluate the impact of time of release on signature composition. The rates of compound decay and evolution of transformation products under the various environmental conditions were monitored in real time. A Fourier transform infrared spectrometer and a gas chromatograph/mass spectrometer were used to determine chemical concentration, evaluate detectability, and identify potential interferences to the detection capability. Specifically, this report describes the initial system function tests with pinacolyl alcohol and methyl iodide and subsequent atmospheric fate experiments with methylphosphonic dichloride and thionyl chloride. Test system function was evaluated using pinacolyl alcohol because as a relatively non-reactive compound, it served as a negative control for the system. Methyl iodide is a compound known …
Date: January 24, 2003
Creator: Driver, Crystal J.; Johnson, Timothy J.; Su, Yin-Fong; Alexander, M. Lizabeth; Fellows, Robert J.; Magnuson, Jon K. et al.
Object Type: Report
System: The UNT Digital Library
Electron Cyclotron Heating and Current Drive for Maintaining Minimum q in Negative Central Shear Discharges (open access)

Electron Cyclotron Heating and Current Drive for Maintaining Minimum q in Negative Central Shear Discharges

Toroidal plasmas created with negative magnetic shear in the core region offer advantages in terms of MHD stability properties. These plasmas, transiently created in several tokamaks, have exhibited high performance as measured by normalized stored energy and neutron production rates. A critical issue with extending the duration of these plasmas is the need to maintain the off-axis-peaked current distribution required to support the minimum in the safety factor q at large radii. We present equilibrium and transport simulations that explore the use of electron cyclotron heating and current drive to maintain this negative shear configuration. Using parameters consistent with DIII-D tokamak operation, we find that with sufficiently high injected power, it is possible to achieve steady-state conditions employing well aligned electron cyclotron and bootstrap current drive in fully non-inductively current-driven configurations.
Date: April 24, 2003
Creator: Casper, T. A.; Kaiser, T. B.; Jong, R. A.; LoDestro, L. L.; Moller, J.; Pearlstein, L. D. et al.
Object Type: Article
System: The UNT Digital Library
FY'03 OMEGA Summary for LLE Annual Report (open access)

FY'03 OMEGA Summary for LLE Annual Report

Lawrence Livermore National Laboratory (LLNL) continued, in FY03, to be a large user of Omega, using 390 experimental shots. These are roughly broken into 2 groups: those in support of the inertial confinement fusion (ICF) program; and those in support of high energy density sciences (HEDS), which includes materials, equation of state, and physics experiments.
Date: October 24, 2003
Creator: Turner, R E
Object Type: Report
System: The UNT Digital Library
RCRA Groundwater Monitoring Plan for Single-Shell Tank Waste Management Area C at the Hanford Site, Interim Change Notice 3 (open access)

RCRA Groundwater Monitoring Plan for Single-Shell Tank Waste Management Area C at the Hanford Site, Interim Change Notice 3

This Interim Change Notice (ICN) updates the radionuclides and sampling schedule in Table 4.3
Date: November 24, 2003
Creator: Narbutovskih, Susan M. (BATTELLE (PACIFIC NW LAB))
Object Type: Report
System: The UNT Digital Library
Noncommutative Dipole Field Theories And Unitarity (open access)

Noncommutative Dipole Field Theories And Unitarity

We extend the argument of Gomis and Mehen for violation of unitarity in field theories with space-time noncommutativity to dipole field theories. In dipole field theories with a timelike dipole vector, we present 1-loop amplitudes that violate the optical theorem. A quantum mechanical system with nonlocal potential of finite extent in time also shows violation of unitarity.
Date: October 24, 2003
Creator: Chiou, Dah-Wei & Ganor, Ori J.
Object Type: Article
System: The UNT Digital Library
Development of All-Solid-State Sensors for Measurement of Nitric Oxide and Ammonia Concentrations by Optical Absorption in Particle-Laden Combusion Exhaust Streams (open access)

Development of All-Solid-State Sensors for Measurement of Nitric Oxide and Ammonia Concentrations by Optical Absorption in Particle-Laden Combusion Exhaust Streams

An all-solid-state continuous-wave (cw) laser system for ultraviolet absorption measurements of the nitric oxide (NO) molecule has been developed and demonstrated. For the NO sensor, 250 nW of tunable cw ultraviolet radiation is produced by sum-frequency-mixing of 532-nm radiation from a diode-pumped Nd:YAG laser and tunable 395-nm radiation from an external cavity diode laser (ECDL). The sum-frequency-mixing process occurs in a beta-barium borate crystal. The nitric oxide absorption measurements are performed by tuning the ECDL and scanning the sum-frequency-mixed radiation over strong nitric oxide absorption lines near 226 nm. The nitric oxide sensor has been used for measurements in the exhaust of a coal-fired laboratory combustion facility. The Texas A&M University boiler burner facility is a 30 kW (100,000 Btu/hr) downward-fired furnace with a steel shell encasing ceramic insulation. Measurements of nitric oxide concentration in the exhaust stream were performed after modification of the facility for laser based NOx diagnostics. The diode-laser-based sensor measurements showed good agreement with the results from physical probe sampling of the combustion exhaust. The diode-laser-based ultraviolet absorption measurements were successful even when the beam was severely attenuated by particulate in the exhaust stream and window fouling. Single-laser-sweep measurements were demonstrated with an effective time resolution …
Date: September 24, 2003
Creator: Caton, Jerald A. & Annamalai, Kalyan
Object Type: Report
System: The UNT Digital Library
Development of Refrigerant Change Indicator and Dirty Air Filter Sensor (open access)

Development of Refrigerant Change Indicator and Dirty Air Filter Sensor

The most common problems affecting residential and light commercial heating, ventilation, and air-conditioning (HVAC) systems are slow refrigerant leaks and dirty air filters. Equipment users are usually not aware of a problem until most of the refrigerant has escaped or the air filter is clogged with dirt. While a dirty air filter can be detected with a technology based on the air pressure differential across the filter, such as a ''whistling'' indicator, it is not easy to incorporate this technology into existing HVAC diagnostic equipment. Oak Ridge National Laboratory is developing a low-cost, nonintrusive refrigerant charge indicator and dirty air filter detection sensor. The sensors, based on temperature measurements, will be inexpensive and easy to incorporate into existing heat pumps and air conditioners. The refrigerant charge indicator is based on the fact that when refrigerant starts to leak, the evaporator coil temperature starts to drop and the level of liquid subcooling drops. When the coil temperature or liquid subcooling drops below a preset reading, a signal, such as a yellow warning light, can be activated to warn the equipment user that the system is undercharged. A further drop of coil temperature or liquid subcooling below another preset reading would trigger …
Date: June 24, 2003
Creator: Mei, V.
Object Type: Report
System: The UNT Digital Library
Evaluation of Chemical Warfare Agent Percutaneous Vapor Toxicity: Derivation of Toxicity Guidelines for Assessing Chemical Protective Ensembles. (open access)

Evaluation of Chemical Warfare Agent Percutaneous Vapor Toxicity: Derivation of Toxicity Guidelines for Assessing Chemical Protective Ensembles.

Percutaneous vapor toxicity guidelines are provided for assessment and selection of chemical protective ensembles (CPEs) to be used by civilian and military first responders operating in a chemical warfare agent vapor environment. The agents evaluated include the G-series and VX nerve agents, the vesicant sulfur mustard (agent HD) and, to a lesser extent, the vesicant Lewisite (agent L). The focus of this evaluation is percutaneous vapor permeation of CPEs and the resulting skin absorption, as inhalation and ocular exposures are assumed to be largely eliminated through use of SCBA and full-face protective masks. Selection of appropriately protective CPE designs and materials incorporates a variety of test parameters to ensure operability, practicality, and adequacy. One aspect of adequacy assessment should be based on systems tests, which focus on effective protection of the most vulnerable body regions (e.g., the groin area), as identified in this analysis. The toxicity range of agent-specific cumulative exposures (Cts) derived in this analysis can be used as decision guidelines for CPE acceptance, in conjunction with weighting consideration towards more susceptible body regions. This toxicity range is bounded by the percutaneous vapor estimated minimal effect (EME{sub pv}) Ct (as the lower end) and the 1% population threshold effect …
Date: July 24, 2003
Creator: Watson, A. P.
Object Type: Report
System: The UNT Digital Library
Deutron photodissociation in ultraperipheral relativistic heavyion on deutron collisions (open access)

Deutron photodissociation in ultraperipheral relativistic heavyion on deutron collisions

In ultraperipheral relativistic deuteron on heavy-ion collisions, a photon emitted from the heavy nucleus may dissociate the deuterium ion. We find deuterium breakup cross sections of 1.24 barns for deuterium-gold collisions at a center of mass energy of 200 GeV per nucleon, as studied at the Relativistic Heavy Ion Collider, and 2.35 barns for deuterium-lead collisions at a center of mass energy of 6.2 TeV, as proposed for the Large Hadron Collider. In the latter case, the cross section is as large as that of hadronic interactions. The estimated error is 5%. We discuss the use of this process as a luminosity monitor and a 'tag' for moderate impact parameter collisions.
Date: March 24, 2003
Creator: Klein, Spencer & Vogt, Ramona
Object Type: Article
System: The UNT Digital Library
Transportation Energy Data Book: Edition 23 (open access)

Transportation Energy Data Book: Edition 23

The ''Transportation Energy Data Book: Edition 23'' is a statistical compendium prepared and published by Oak Ridge National Laboratory (ORNL) under contract with the Office of Planning, Budget Formulation, and Analysis, under the Energy Efficiency and Renewable Energy (EERE) program in the Department of Energy (DOE). Designed for use as a desk-top reference, the data book represents an assembly and display of statistics and information that characterize transportation activity, and presents data on other factors that influence transportation energy use. The purpose of this document is to present relevant statistical data in the form of tables and graphs. The latest editions of the Data Book are available to a larger audience via the Internet (www-cta.ornl.gov/data). This edition of the Data Book has 12 chapters which focus on various aspects of the transportation industry. Chapter 1 focuses on petroleum; Chapter 2--energy; Chapter 3--highway vehicles; Chapter 4--light vehicles; Chapter 5--heavy vehicles; Chapter 6--alternative fuel vehicles; Chapter 7--fleet vehicles; Chapter 8--household vehicles; and Chapter 9--nonhighway modes; Chapter 10--transportation and the economy; Chapter 11--greenhouse gas emissions; and Chapter 12--criteria pollutant emissions. The sources used represent the latest available data. There are also three appendices which include detailed source information for some tables, measures of …
Date: October 24, 2003
Creator: Davis, S.C.
Object Type: Report
System: The UNT Digital Library
An in situ transmission electron microscopy study of the thermalstability of near-surface microstructures induced by deep rolling andlaser-shock peening (open access)

An in situ transmission electron microscopy study of the thermalstability of near-surface microstructures induced by deep rolling andlaser-shock peening

Mechanical surface treatments are known to be effective at improving the fatigue resistance of metallic alloys at elevated temperatures ({approx}550-600 C), even though the near-surface compressive residual stress fields have been annealed out. We have investigated the thermal stability of near-surface microstructures induced by deep rolling and laser-shock peening in an austentic stainless steel (AISI 304) and a titanium alloy (Ti-6Al-4V) using in situ hot-stage transmission electron microscopy. It is found that the improvements in fatigue resistance at elevated temperature are related to the high-temperature stability of the work-hardened near-surface microstructure in each case.
Date: February 24, 2003
Creator: Altenberger, I.; Stach, E. A.; Liu, G. Y.; Nalla, R. K. & Ritchie, R. O.
Object Type: Article
System: The UNT Digital Library
Measurements of Water and B4C Content of Rackable Can Storage Boxes for HEU Storage at the HEUMF at the Y-12 National Security Complex (open access)

Measurements of Water and B4C Content of Rackable Can Storage Boxes for HEU Storage at the HEUMF at the Y-12 National Security Complex

Extensive measurements at the Oak Ridge National Laboratory (ORNL) with BoroBond{trademark} blocks of varying thickness, natural boron carbide (B{sub 4}C) content, and water content, and with a simplified mockup of the Rackable Can Storage Box (RCSB) of fixed natural B{sub 4}C and water content, have led to a method of quantifying the water content of RCSBs by fast neutron time-of-flight transmission measurements (NMIS)* and quantifying the B{sub 4}C content with gamma ray spectrometry assuming the water content is known. The time-of-flight transmission measurements results can also be used to assess the uniformity of the BoroBond{trademark} in the RCSB. The data from both measurements will be stored for future comparisons to initial measurements. These methods can also be implemented at the RCSB production site, or subsequently at the Y-12 National Security Complex during the operating lifetime of the RCSBs at the Highly Enriched Uranium Materials Facility.
Date: March 24, 2003
Creator: Neal, JS
Object Type: Report
System: The UNT Digital Library
Plans and Progress on Hanford MLLW Treatment and Disposal (open access)

Plans and Progress on Hanford MLLW Treatment and Disposal

Mixed low-level waste (MLLW) contains both low-level radioactive materials and low-level hazardous chemicals. The hazardous component of mixed waste has characteristics identified by any or all of the following statutes: the Resource Conservation and Recovery Act of 1976 (RCRA), as amended; the Toxic Substances Control Act of 1976; and Washington State dangerous waste regulations. The Fluor Hanford Waste Management Project (WMP) is responsible for storing, treating, and disposing of solid MLLW, which includes organic and inorganic solids, organics and inorganic lab packs, debris, lead, mercury, long-length equipment, spent melters, and remote-handled (RH) and oversized MLLW. Hanford has 7,000 cubic meters, or about 25%, of the MLLW in storage at U.S. Department of Energy (DOE) sites. Hanford plans to receive 57,000 cubic meters from on-site generators, or about 50% of DOE's newly generated MLLW. In addition, the Hanford Environment Restoration Program and off-site generators having approved Federal Facility Consent Agreement site treatment plans will most likely send 200 cubic meters of waste to be treated and returned to the generators. Volumes of off-site waste receipts will be affected when the MLLW Record of Decision is issued as part of the process for the Hanford Site Solid Waste Environmental Impact Statement (EIS). …
Date: February 24, 2003
Creator: McDonald, K. M.; Blackford, L. T.; Nester, D. E.; Connolly, R. R.; McKenney, D. E. & Moy, S. K.
Object Type: Article
System: The UNT Digital Library
Laser plasma interactions in fused silica cavities (open access)

Laser plasma interactions in fused silica cavities

The effect of laser energy on formation of a plasma inside a cavity was investigated. The temperature and electron number density of laser-induced plasmas in a fused silica cavity were determined using spectroscopic methods, and compared with laser ablation on a flat surface. Plasma temperature and electron number density during laser ablation in a cavity with aspect ratio of 4 increased faster with irradiance after the laser irradiance reached a threshold of 5 GW/cm{sup 2}. The threshold irradiance of particulate ejection was lower for laser ablation in a cavity compared with on a flat surface; the greater the cavity aspect ratio, the lower the threshold irradiance. The ionization of silicon becomes saturated and the crater depths were increased approximately by an order of magnitude after the irradiance reached the threshold. Phase explosion was discussed to explain the large change of both plasma characteristics and mass removal when irradiance increased beyond a threshold value. Self-focusing of the laser beam was discussed to be responsible for the decrease of the threshold in cavities.
Date: June 24, 2003
Creator: Zeng, Xianzhong; Mao, Xianglei; Mao, Samuel S.; Yoo, Jong H.; Greif, Ralph & Russo, Richard E.
Object Type: Article
System: The UNT Digital Library
PERFORMANCE AND DURABILITY OF THE PSA PEUGEOT CITROEN'S DPF SYSTEM ON A TAXI FLEET IN THE PARIS AREA (open access)

PERFORMANCE AND DURABILITY OF THE PSA PEUGEOT CITROEN'S DPF SYSTEM ON A TAXI FLEET IN THE PARIS AREA

The use of Diesel engines has strongly increased during the last years and now represents 40% of the sales in Europe and up to 50% of the number of cars in circulation for some countries. This success is linked not only to the economical aspect of the use of such vehicles, but also to the recent technological improvements of these engines. The new technical solutions (high pressure direct injection, turbocharger) have indeed allowed the increase of these engine performances while decreasing their fuel consumption, pollutant emissions and noise level. From an environment point of view, Diesel engines are nevertheless penalized by their particulates and NOx emissions. The study and the treatment of the particulate, highly criticized for their potential impact on health, are the subject of numerous works of characterizations and developments. PSA Peugeot Citroen has recently (2000) launched its particulate filter technology on several types of vehicles (500,000 vehicles with DPF have been sold today). In order to evaluate the durability of this technology over a long period of time, a study program has been set-up by ADEME (French Environmental Agency), IFP Powertrain, PSA Peugeot Citroen and Taxis G7 (a Parisian taxis Company). The objective is to study the …
Date: August 24, 2003
Creator: COROLLER, P & PLASSAT, G
Object Type: Article
System: The UNT Digital Library
General Corrosion and Localized Corrosion of the Drip Shield (open access)

General Corrosion and Localized Corrosion of the Drip Shield

The recommended waste package (WP) design is described in BSC (2001a). The design includes a double-wall WP underneath a protective drip shield (DS) (BSC 2003a). The purpose of the process-level models developed in this report is to model dry oxidation (DOX), general corrosion (GC) and localized corrosion (LC) of the DS plate material, which is made of Ti Grade 7. The DS design also includes structural supports fabricated from Ti Grade 24. Degradation of Ti Grade 24 is not considered in this report. The DS provides protection for the waste package outer barrier (WPOB) both as a barrier to seepage water contact and a physical barrier to potential rockfall. This Model Report (MR) serves as a feed to the Integrated Waste Package Degradation Model (IWPD) analyses, and was developed in accordance with the Technical Work Plan (TWP) (BSC 2002a). The models contained in this report serve as a basis to determine whether or not the performance requirements for the DS can be met.
Date: June 24, 2003
Creator: Hua, F. & Mon, K.
Object Type: Report
System: The UNT Digital Library
Improved Refractories for Slagging Gasifiers in IGCC Power Systems (open access)

Improved Refractories for Slagging Gasifiers in IGCC Power Systems

The gasification of coal and other carbon-containing fuels provides the opportunity to produce energy more efficiently, and with significantly less environmental impact, than more-conventional combustion-based processes. In addition, the synthesis gas that is the product of the gasification process offers the option of ''polygeneration,'' i.e., the production of alternative products instead of power should it be economically favorable to do so. Because of these advantages, gasification is viewed as one of the key processes in the U.S. Department of Energy's Vision 21 power system. However, issues with both the reliability and the economics of gasifier operation will have to be resolved before gasification will be widely adopted by the power industry. Central to both enhanced reliability and economics is the development of materials with longer service lives in gasifier systems that can provide extended periods of continuous, trouble-free gasifier operation. The focus of the Advanced Refractories for Gasification project at the Albany Research Center is to develop improved refractory materials capable of withstanding the harsh, high-temperature environment created by the gasification reaction, and includes both the refractory lining that protects and insulates the slagging gasifier, as well as the thermocouple assemblies that are utilized to monitor gasifier operating temperatures. Current …
Date: April 24, 2003
Creator: Dogan, Cynthia P.; Kwong, Kyei-Sing; Bennett, James P. & Chinn, Richard E.
Object Type: Article
System: The UNT Digital Library
Stabilization of Mercury in High pH Tank Sludges (open access)

Stabilization of Mercury in High pH Tank Sludges

DOE complex contains many tank sludges contaminated with mercury. The high pH of these tank sludges typically fails to stabilize the mercury, resulting in these radioactive wastes also being characteristically hazardous or mixed waste. The traditional treatment for soluble inorganic mercury species is precipitation as insoluble mercuric sulfide. Sulfide treatment and a commercial mercury-stabilizing product were tested on surrogate sludges at various alkaline pH values. Neither the sulfide nor the commercial product stabilized the mercury sufficiently at the high pH of the tank sludges to pass the Toxicity Characteristic Leach Procedure (TCLP) treatment standards of the Resource Conservation and Recovery Act (RCRA). The commercial product also failed to stabilize the mercury in samples of the actual tank sludges.
Date: February 24, 2003
Creator: Spence, R. & Barton, J.
Object Type: Article
System: The UNT Digital Library
HYDROGEN GENERATION FROM PLASMATRON REFORMERS: A PROMISING TECHNOLOGY FOR NOX ADSORBER REGENERATION AND OTHER AUTOMOTIVE APPLICATIONS (open access)

HYDROGEN GENERATION FROM PLASMATRON REFORMERS: A PROMISING TECHNOLOGY FOR NOX ADSORBER REGENERATION AND OTHER AUTOMOTIVE APPLICATIONS

Plasmatron reformers are being developed at MIT and ArvinMeritor [1]. In these reformers a special low power electrical discharge is used to promote partial oxidation conversion of hydrocarbon fuels into hydrogen and CO. The partial oxidation reaction of this very fuel rich mixture is difficult to initiate. The plasmatron provides continuous enhanced volume initiation. To minimize electrode erosion and electrical power requirements, a low current, high voltage discharge with wide area electrodes is used. The reformers operate at or slightly above atmospheric pressure. Plasmatron reformers provide the advantages of rapid startup and transient response; efficient conversion of the fuel to hydrogen rich gas; compact size; relaxation or elimination of reformer catalyst requirements; and capability to process difficult to reform fuels, such as diesel and bio-oils. These advantages facilitate use of onboard hydrogen-generation technology for diesel exhaust after-treatment. Plasma-enhanced reformer technology can provide substantial conversion even without the use of a catalyst. Recent progress includes a substantial decrease in electrical power consumption (to about 200 W), increased flow rate (above 1 g/s of diesel fuel corresponding to approximately 40 kW of chemical energy), soot suppression and improvements in other operational features.. Plasmatron reformer technology has been evaluated for regeneration of NOx …
Date: August 24, 2003
Creator: Bromberg, L.; Crane, S; Rabinovich, A.; Kong, Y; Cohn, D; Heywood, J et al.
Object Type: Article
System: The UNT Digital Library
Development of Novel Electrocatalysts for Proton Exchange Membrane Fuel Cells: Final Report (open access)

Development of Novel Electrocatalysts for Proton Exchange Membrane Fuel Cells: Final Report

Fuel cells are electrochemical devices that convert the available chemical free energy directly into electrical energy, without going through heat exchange process. Of all different types of fuel cells, the Proton Exchange Membrane Fuel Cell (PEMFC) is one of the most promising power sources for stand-alone utility and electric vehicle applications. Platinum (Pt) Catalyst is used for both fuel and air electrodes in PEMFCs. However, carbon monoxide (CO) contamination of H{sub 2} greatly affects electro catalysts used at the anode of PEMFCs and decreases cell performance. The irreversible poisoning of the anode can occur even in CO concentrations as low as few parts per million (ppm). In this work, we have synthesized several novel elctrocatalysts (Pt/C, Pt/Ru/C, Pt/Mo/C, Pt/Ir and Pt/Ru/Mo) for PEMFCs. These catalysts have been tested for CO tolerance in the H{sub 2}/air fuel cell, using CO concentrations in the H{sub 2} fuel that varies from 10 to 100 ppm. The performance of the electrodes was evaluated by determining the cell potential against current density. The effects of catalyst composition and electrode film preparation method on the performance of PEM fuel cell were also studied. It was found that at 70 C and 3.5 atm pressure at the …
Date: April 24, 2003
Creator: Ilias, Shamsuddin
Object Type: Report
System: The UNT Digital Library
Global Climate Change and the Transportation Sector: An Update on Issues and Mitigation Options (open access)

Global Climate Change and the Transportation Sector: An Update on Issues and Mitigation Options

It is clear from numerous energy/economic modeling exercises that addressing the challenges posed by global climate change will eventually require the active participation of all industrial sectors and all consumers on the planet. Yet, these and similar modeling exercises indicate that large stationary CO2 point sources (e.g., refineries and fossil-fired electric power plants) are often the first targets considered for serious CO2 emissions mitigation. Without participation of all sectors of the global economy, however, the challenges of climate change mitigation will not be met. Because of its operating characteristics, price structure, dependence on virtually one energy source (oil), enormous installed infrastructure, and limited technology alternatives, at least in the near-term, the transportation sector will likely represent a particularly difficult challenge for CO2 emissions mitigation. Our research shows that climate change induced price signals (i.e., putting a price on carbon that is emitted to the atmosphere) are in the near term insufficient to drive fundamental shifts in demand for energy services or to transform the way these services are provided in the transportation sector. We believe that a technological revolution will be necessary to accomplish the significant reduction of greenhouse gas emissions from the transportation sector. This paper presents an update …
Date: August 24, 2003
Creator: Geffen, C. A.; Dooley, J. J. & Kim, S. H.
Object Type: Article
System: The UNT Digital Library
APBF-DEC NOx Adsorber/DPF Project: Light-Duty Passenger Car Platform (open access)

APBF-DEC NOx Adsorber/DPF Project: Light-Duty Passenger Car Platform

A 1.9L turbo direct injection (TDI) diesel engine was modified to achieve the upcoming Tier 2 Bin 5 emission standard in combination with a NOx adsorber catalyst (NAC) and a diesel particulate filter (DPF). The primary objective for developing this test bed is to investigating the effects of different fuel sulfur contents on the performance of an advanced emission control system (ECS) in a light-duty application. During the development process, the engine-out emissions were minimized by applying a state-of-the-art combustion system in combination with cooled exhaust gas recirculation (EGR). The subsequent calibration effort resulted in emission levels requiring 80-90 percent nitrogen-oxide (NOx) and particulate matter (PM) conversion rates by the corresponding ECS. The strategy development included ean/rich modulation for NAC regeneration, as well as, the desulfurization of the NAC and the regeneration of the DPF. Two slightly different ECS were investigated and calibrated. The initial vehicle results in an Audi A4 station wagon over the federal test procedure (FTP), US 06, and the highway fuel economy test (HFET) cycle indicate the potential of these configuration to meet the future Tier 2 emission standard.
Date: August 24, 2003
Creator: Tomazic, D; Tatur, M & Thornton, M
Object Type: Article
System: The UNT Digital Library