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Full-Text Articles in Environmental Chemistry
Utah Wintertime Measurements Of Heavy-Duty Vehicle Nitrogen Oxide Emission Factors, Gary A. Bishop, Molly J. Haugen, Brian C. Mcdonald, Adam M. Boies
Utah Wintertime Measurements Of Heavy-Duty Vehicle Nitrogen Oxide Emission Factors, Gary A. Bishop, Molly J. Haugen, Brian C. Mcdonald, Adam M. Boies
Fuel Efficiency Automobile Test Publications
There have only been a few wintertime studies of heavy-duty vehicle (HDV) NOx emissions in the U.S., and while they have observed increased emissions, fleet characterization to identify the cause has been lacking. We have collected wintertime measurements of NOx emission factors from 1,591 HDV at a Utah Port of Entry in December 2020 that includes individual vehicle identification. In general, the NOx emission factors for 2011 & newer chassis model year HDV are significantly higher than 2017 spring measurements from California. The newest chassis model year HDV (2017 - 2021) NOx emission factors are similar …
Winter Measurements Of Heavy-Duty Vehicles To Characterize The Cold Temperature Effectiveness Of Selective Catalytic Reductions Catalyst In Controlling Oxide Of Nitrogen Emissions, Gary A. Bishop, Molly J. Haugen, Brian C. Mcdonald
Winter Measurements Of Heavy-Duty Vehicles To Characterize The Cold Temperature Effectiveness Of Selective Catalytic Reductions Catalyst In Controlling Oxide Of Nitrogen Emissions, Gary A. Bishop, Molly J. Haugen, Brian C. Mcdonald
Fuel Efficiency Automobile Test Publications
No abstract provided.
On-Road Remote Sensing Of Heavy And Medium-Duty Trucks At The Peralta Weigh Station In The South Coast Air Basin: Spring 2017, Molly J. Haugen, Gary A. Bishop
On-Road Remote Sensing Of Heavy And Medium-Duty Trucks At The Peralta Weigh Station In The South Coast Air Basin: Spring 2017, Molly J. Haugen, Gary A. Bishop
Fuel Efficiency Automobile Test Publications
No abstract provided.
Evaluation Of Heavy- And Medium-Duty On-Road Vehicle Emissions In California's South Coast Air Basin, Molly J. Haugen, Gary A. Bishop, Arvind Thiruvengadam, Daniel K. Carder
Evaluation Of Heavy- And Medium-Duty On-Road Vehicle Emissions In California's South Coast Air Basin, Molly J. Haugen, Gary A. Bishop, Arvind Thiruvengadam, Daniel K. Carder
Fuel Efficiency Automobile Test Publications
Emission measurements were collected from heavy-duty (HDVs) and medium-duty vehicles (MDVs) at the Peralta weigh station long-term measurement site near Anaheim, CA in 2017. Two Fuel Efficiency Automobile Test units sampled elevated and ground-level exhaust vehicles totaling 2,315 measurements. HDVs (1844 measurements) exhibited historical reductions in fuel specific oxides of nitrogen (NOx) from the 2008 measurements (55%) with increased use of exhaust gas recirculation and selective catalytic reduction systems. However, as these technologies have aged, the in-use benefits have declined. Infrared %opacity measurements of tailpipe soot decreased 14% since 2012 with increased diesel particulate filter (DPF) use, DPF …
Investigate The Durability Of Diesel Engine Emission Controls, Gary A. Bishop, Molly J. Haugen
Investigate The Durability Of Diesel Engine Emission Controls, Gary A. Bishop, Molly J. Haugen
Fuel Efficiency Automobile Test Publications
No abstract provided.
Long-Term Fuel-Specific Nox And Particle Emission Trends For In-Use Heavy-Duty Vehicles In California, Molly J. Haugen, Gary A. Bishop
Long-Term Fuel-Specific Nox And Particle Emission Trends For In-Use Heavy-Duty Vehicles In California, Molly J. Haugen, Gary A. Bishop
Fuel Efficiency Automobile Test Publications
Two California heavy-duty fleets have been measured in 2013, 2015 and 2017 using the On-road Heavy-duty Measurement System. The Port of Los Angeles drayage fleet has increased in age by 3.3 model years (4.2 to 7.5 years old) since 2013, with little fleet turnover. Large increases in fuel specific particle emissions (PM) observed in 2015 were reversed in 2017, returning to near 2013 levels, suggesting repairs and or removal of high emitting vehicles. Fuel specific oxides of nitrogen (NOx) emissions of this fleet have increased and NOx after-treatment systems do not appear to perform ideally in this …
Repeat Fuel Specific Emission Measurements On Two California Heavy-Duty Truck Fleets, Molly J. Haugen, Gary A. Bishop
Repeat Fuel Specific Emission Measurements On Two California Heavy-Duty Truck Fleets, Molly J. Haugen, Gary A. Bishop
Fuel Efficiency Automobile Test Publications
The University of Denver repeated its 2013 fuel specific gaseous and particle emission measurements on two California heavy-duty vehicle fleets. In 2015 1,457 measurements at the Port of Los Angeles and 694 measurements at the Cottonwood weigh station in northern California were collected. The Port fleet changed little since 2013, increasing the average age (+1.8 years), accompanied by an increase in particle mass (PM) by +266% (0.03 ± 0.01 to 0.11 ± 0.01 gPM/kg of fuel) and black carbon (BC) by +300% (0.02 ± 0.003 to 0.08 ± 0.01 gBC/kg of fuel). Particle number (PN) also increased (1.5 x 10 …
Heavy Duty Truck Emissions (Presentation), Donald H. Stedman, Gary A. Bishop
Heavy Duty Truck Emissions (Presentation), Donald H. Stedman, Gary A. Bishop
Fuel Efficiency Automobile Test Publications
No abstract provided.
Remote Measurements Of On-Road Emissions From Heavy-Duty Diesel Vehicles In California; Year 5, 2012, Gary A. Bishop, Donald H. Stedman
Remote Measurements Of On-Road Emissions From Heavy-Duty Diesel Vehicles In California; Year 5, 2012, Gary A. Bishop, Donald H. Stedman
Fuel Efficiency Automobile Test Publications
No abstract provided.
Emission Trends In Heavy-Duty Trucks In The South Coast Air Basin (Presentation), Gary A. Bishop, Brent G. Schuchmann, Donald H. Stedman
Emission Trends In Heavy-Duty Trucks In The South Coast Air Basin (Presentation), Gary A. Bishop, Brent G. Schuchmann, Donald H. Stedman
Fuel Efficiency Automobile Test Publications
No abstract provided.
Heavy-Duty Truck Emissions In The South Coast Air Basin Of California, Gary A. Bishop, Brent G. Schuchmann, Donald H. Stedman
Heavy-Duty Truck Emissions In The South Coast Air Basin Of California, Gary A. Bishop, Brent G. Schuchmann, Donald H. Stedman
Fuel Efficiency Automobile Test Publications
California and Federal emissions regulations for 2007 and newer heavy-duty diesel engines require an order of magnitude reduction in particulate matter and oxides of nitrogen spurring the introduction of new aftertreatment systems. Since 2008 four emission measurement campaigns have been conducted at a Port of Los Angeles location and an inland weigh station in the South Coast Air Basin of California. Fuel specific oxides of nitrogen emissions at the Port have decreased 12% since 2010 while infrared opacity (a measure of particulate matter) remained low, showing no diesel particulate filter deterioration. The weigh station truck’s fuel specific oxides of nitrogen …
Emission Changes Resulting From The San Pedro Bay, California Ports Truck Retirement Program, Gary A. Bishop, Brent G. Schuchmann, Donald H. Stedman, Douglas R. Lawson
Emission Changes Resulting From The San Pedro Bay, California Ports Truck Retirement Program, Gary A. Bishop, Brent G. Schuchmann, Donald H. Stedman, Douglas R. Lawson
Fuel Efficiency Automobile Test Publications
Recent US EPA emissions regulations have resulted in lower emissions of particulate matter and oxides of nitrogen from heavy-duty diesel trucks. To accelerate fleet turnover the State of California in 2008 along with the Ports of Los Angeles and Long Beach (San Pedro Bay Ports) in 2006 passed regulations establishing timelines forcing the retirement of older diesel trucks. On-road emissions measurements of heavy-duty diesel trucks were collected over a three-year period, beginning in 2008, at a Port of Los Angeles location and an inland weigh station on the Riverside freeway (CA SR91). At the Port location the mean fleet age …
Remote Measurements Of On-Road Emissions From Heavy-Duty Diesel Vehicles In California; Year 2, 2009, Brent G. Schuchmann, Gary A. Bishop, Donald H. Stedman
Remote Measurements Of On-Road Emissions From Heavy-Duty Diesel Vehicles In California; Year 2, 2009, Brent G. Schuchmann, Gary A. Bishop, Donald H. Stedman
Fuel Efficiency Automobile Test Publications
No abstract provided.
Remote Measurements Of On-Road Emissions From Heavy-Duty Diesel Vehicles In California; Year 3, 2010, Brent G. Schuchmann, Gary A. Bishop, Donald H. Stedman
Remote Measurements Of On-Road Emissions From Heavy-Duty Diesel Vehicles In California; Year 3, 2010, Brent G. Schuchmann, Gary A. Bishop, Donald H. Stedman
Fuel Efficiency Automobile Test Publications
No abstract provided.
Correlation Of The Real-Time Particulate Matter Emissions Measurements Of A Esp Remote Sensing Device (Rsd) And A Dekati Electronic Tailpipe Sensor (Etaps) With Gravimetrically Measured Pm From A Total Exhaust Dilution Tunnel System, Mridul Gautam, Donald H. Stedman, Daniel K. Carder, Benjamin Shade, Nigel Clark, Gregory Thompson, Scott Wayne, Gary A. Bishop, Brent G. Schuchmann, Dan Pope, Niranjan Vescio, Gary Full, Peter Mcclintock, Drew Rau
Correlation Of The Real-Time Particulate Matter Emissions Measurements Of A Esp Remote Sensing Device (Rsd) And A Dekati Electronic Tailpipe Sensor (Etaps) With Gravimetrically Measured Pm From A Total Exhaust Dilution Tunnel System, Mridul Gautam, Donald H. Stedman, Daniel K. Carder, Benjamin Shade, Nigel Clark, Gregory Thompson, Scott Wayne, Gary A. Bishop, Brent G. Schuchmann, Dan Pope, Niranjan Vescio, Gary Full, Peter Mcclintock, Drew Rau
Fuel Efficiency Automobile Test Publications
No abstract provided.
Remote Measurements Of On-Road Emissions From Heavy-Duty Diesel Vehicles In California; Year 1, 2008, Gary A. Bishop, Nicolas E. Holubowitch, Donald H. Stedman
Remote Measurements Of On-Road Emissions From Heavy-Duty Diesel Vehicles In California; Year 1, 2008, Gary A. Bishop, Nicolas E. Holubowitch, Donald H. Stedman
Fuel Efficiency Automobile Test Publications
No abstract provided.
On-Road Remote Sensing Of Heavy-Duty Diesel Truck Emissions In The Austin- San Marcos Area: August 1998, Jerome A. Morris, Gary A. Bishop, Donald H. Stedman
On-Road Remote Sensing Of Heavy-Duty Diesel Truck Emissions In The Austin- San Marcos Area: August 1998, Jerome A. Morris, Gary A. Bishop, Donald H. Stedman
Fuel Efficiency Automobile Test Publications
No abstract provided.