Open Access. Powered by Scholars. Published by Universities.®

Environmental Chemistry Commons™

Open Access. Powered by Scholars. Published by Universities.®

Articles 31 - 60 of 162

Full-Text Articles in Environmental Chemistry

Evaluation Of Emissions Benefits Of Federal Reformulated Gasoline Versus Conventional Gasoline, Gary A. Bishop, S. Kent Hoekman, Amber Broch Jan 2018

Evaluation Of Emissions Benefits Of Federal Reformulated Gasoline Versus Conventional Gasoline, Gary A. Bishop, S. Kent Hoekman, Amber Broch

Fuel Efficiency Automobile Test Publications

No abstract provided.


Repeat Fuel Specific Emission Measurements On Two California Heavy-Duty Truck Fleets, Molly J. Haugen, Gary A. Bishop Jan 2017

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 …


On-Road Remote Sensing Of Automobile Emissions In The Chicago Area: Fall 2016, Gary A. Bishop, Molly J. Haugen Jan 2017

On-Road Remote Sensing Of Automobile Emissions In The Chicago Area: Fall 2016, Gary A. Bishop, Molly J. Haugen

Fuel Efficiency Automobile Test Publications

No abstract provided.


United States Light And Heavy -Duty Fuel Specific On -Road No And No X Emission Factor Trends And Their Importance In Inventory Calculations (Presentation), Gary A. Bishop Jan 2017

United States Light And Heavy -Duty Fuel Specific On -Road No And No X Emission Factor Trends And Their Importance In Inventory Calculations (Presentation), Gary A. Bishop

Fuel Efficiency Automobile Test Publications

No abstract provided.


Measuring Real-World Emissions From The On-Road Passenger Fleet, Gary A. Bishop, Donald H. Stedman Jan 2016

Measuring Real-World Emissions From The On-Road Passenger Fleet, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.


On-Road Remote Sensing Of Automobile Emissions In The Tulsa Area: Fall 2015, Gary A. Bishop, Donald H. Stedman Jan 2016

On-Road Remote Sensing Of Automobile Emissions In The Tulsa Area: Fall 2015, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.


Donald H. Stedman 50 Years Of Air Quality Instrument Inventions And Measurements (Presentation), Gary A. Bishop, Donald H. Stedman Jan 2016

Donald H. Stedman 50 Years Of Air Quality Instrument Inventions And Measurements (Presentation), Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.


High-Mileage Light-Duty Fleet Vehicle Emissions: Their Potentially Overlooked Importance, Gary A. Bishop, Donald H. Stedman, Daniel A. Burgard, Oscar Atkinson Jan 2016

High-Mileage Light-Duty Fleet Vehicle Emissions: Their Potentially Overlooked Importance, Gary A. Bishop, Donald H. Stedman, Daniel A. Burgard, Oscar Atkinson

Fuel Efficiency Automobile Test Publications

No abstract provided.


On-Road Heavy-Duty Vehicle Emissions Monitoring System, Gary A. Bishop, Rachel Hottor-Raguindin, Donald H. Stedman, Peter Mcclintock, Ed Theobald, Jeremy D. Johnson, Doh-Won Lee, Josias Zietsman, Chandan Misra Jan 2015

On-Road Heavy-Duty Vehicle Emissions Monitoring System, Gary A. Bishop, Rachel Hottor-Raguindin, Donald H. Stedman, Peter Mcclintock, Ed Theobald, Jeremy D. Johnson, Doh-Won Lee, Josias Zietsman, Chandan Misra

Fuel Efficiency Automobile Test Publications

The introduction of particulate and oxides of nitrogen (NOx) after-treatment controls on heavy-duty vehicles has spurred the need for fleet emissions data to monitor their reliability and effectiveness. The University of Denver has developed a new method for rapidly measuring heavy-duty vehicles for gaseous and particulate fuel specific emissions. The method was recently used to collect 3,088 measurements at a Port of Los Angeles location and a weigh station on I-5 in northern California. The weigh station NOx emissions for 2014 models are 73% lower than 2010 models (3.8 vs. 13.9 gNOx/kg of fuel) and …


Real ‐ World Vehicle Emissions Measurements (Presentation), Gary A. Bishop Jan 2015

Real ‐ World Vehicle Emissions Measurements (Presentation), Gary A. Bishop

Fuel Efficiency Automobile Test Publications

No abstract provided.


Reactive Nitrogen Species Emission Trends In Three Light-/Medium-Duty United States Fleets, Gary A. Bishop, Donald H. Stedman Jan 2015

Reactive Nitrogen Species Emission Trends In Three Light-/Medium-Duty United States Fleets, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

Repeated, fuel specific, emission measurements in Denver (2005/2013), Los Angeles (2008/2013) and Tulsa (2005/2013) provide long-term trends in on-road reactive nitrogen emissions from three light/medium duty U.S. fleets. Reductions in oxides of nitrogen (NOx) emissions ranged from 21% in Denver (5.6 ± 1.3 to 4.4 ± 0.2 gNOx/kg of fuel) to 43% in Tulsa (4.4 ± 0.3 to 2.5 ± 0.1 gNOx/kg of fuel) since 2005 while decreases in fleet ammonia (NH3) emissions ranged from no change in Denver (0.45 ± 0.09 to 0.44 ± 0.02 gNH3/kg of fuel) since 2005 to …


On-Road Remote Sensing Of Automobile Emissions In The Chicago Area: Fall 2014, Gary A. Bishop, Donald H. Stedman Jan 2015

On-Road Remote Sensing Of Automobile Emissions In The Chicago Area: Fall 2014, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.


Rsd Basics (Presentation), Donald H. Stedman, Gary A. Bishop Jan 2014

Rsd Basics (Presentation), Donald H. Stedman, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

No abstract provided.


Feat Math Ii And A Discussion Of Negative Measurements, Gary A. Bishop Jan 2014

Feat Math Ii And A Discussion Of Negative Measurements, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

No abstract provided.


Heavy Duty Truck Emissions (Presentation), Donald H. Stedman, Gary A. Bishop Jan 2014

Heavy Duty Truck Emissions (Presentation), Donald H. Stedman, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

No abstract provided.


On-Road Remote Sensing Of Automobile Emissions In The Tulsa Area: Fall 2013, Gary A. Bishop, Donald H. Stedman Jan 2014

On-Road Remote Sensing Of Automobile Emissions In The Tulsa Area: Fall 2013, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.


On-Road Remote Sensing Of Automobile Emissions In The Denver Area: Winter 2013, Gary A. Bishop, Donald H. Stedman Jan 2014

On-Road Remote Sensing Of Automobile Emissions In The Denver Area: Winter 2013, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.


Colorado Long Term Light-Duty Vehicle On-Road Emission Trends (Presentation), Gary A. Bishop, Donald H. Stedman Jan 2014

Colorado Long Term Light-Duty Vehicle On-Road Emission Trends (Presentation), Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.


The Recession Of 2008 And Its Impact On Light-Duty Vehicle Emissions In Three Western Us Cities, Gary A. Bishop, Donald H. Stedman Jan 2014

The Recession Of 2008 And Its Impact On Light-Duty Vehicle Emissions In Three Western Us Cities, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

The global economic recession of 2008 - 2010 severely depressed light-duty vehicle sales in the United States. On-road fleets observed with a remote vehicle exhaust sensor in 2013 at three historical sampling locations in Denver, Los Angeles and Tulsa showed large reductions in the fleet fractions of 2009 model year vehicles of 40%, 38% and 35% respectively when compared to prerecession 2007 levels with the light-duty truck category suffering the largest percentage declines. The fleet fraction for these ~5 year old vehicles is normally reserved for vehicles more than twice their age. This resulted in a significant increase in the …


Remote Measurements Of On-Road Emissions From Heavy-Duty Diesel Vehicles In California; Year 5, 2012, Gary A. Bishop, Donald H. Stedman Jan 2013

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.


Heavy-Duty Truck Emissions In The South Coast Air Basin Of California, Gary A. Bishop, Brent G. Schuchmann, Donald H. Stedman Jan 2013

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 Trends In Heavy-Duty Trucks In The South Coast Air Basin (Presentation), Gary A. Bishop, Brent G. Schuchmann, Donald H. Stedman Jan 2013

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.


Yellowstone Over-Snow Vehicle Emission Tests – 2012, John D. Ray, Gary A. Bishop, Brent G. Schuchmann, Chris Frey, Gurdas Sandhu, Brandon Graver Jan 2013

Yellowstone Over-Snow Vehicle Emission Tests – 2012, John D. Ray, Gary A. Bishop, Brent G. Schuchmann, Chris Frey, Gurdas Sandhu, Brandon Graver

Fuel Efficiency Automobile Test Publications

No abstract provided.


Multi-Species Remote Sensing Of Vehicle Emissions On Sherman Way In Van Nuys California, Gary A. Bishop, Brent G. Schuchmann, Donald H. Stedman, Douglas R. Lawson Jan 2012

Multi-Species Remote Sensing Of Vehicle Emissions On Sherman Way In Van Nuys California, Gary A. Bishop, Brent G. Schuchmann, Donald H. Stedman, Douglas R. Lawson

Fuel Efficiency Automobile Test Publications

As part of the 2010 Van Nuys tunnel study, researchers from the University of Denver measured on-road fuel-specific light-duty vehicle emissions from nearly 13,000 vehicles on Sherman Way (0.4 miles west of the tunnel) in Van Nuys, CA with its multi-species FEAT remote sensor a week ahead of the tunnel measurements. The remote sensing mean gram per kilogram carbon monoxide (CO), hydrocarbons (HC), and oxides of nitrogen (NOx) measurements are 8.9% lower, 41%, and 24% higher than the tunnel measurements respectively. The remote sensing CO/NOx and HC/NOx mass ratios are 28% lower and 20% higher than …


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 Jan 2012

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 …


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 Jan 2010

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.


Multi-Species On-Road Remote Sensing Of Vehicle Emissions In Van Nuys, California – August 2010, Gary A. Bishop, Brent G. Schuchmann, Donald H. Stedman Jan 2010

Multi-Species On-Road Remote Sensing Of Vehicle Emissions In Van Nuys, California – August 2010, Gary A. Bishop, Brent G. Schuchmann, 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 2, 2009, Brent G. Schuchmann, Gary A. Bishop, Donald H. Stedman Jan 2010

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 Jan 2010

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.


On-Road Emission Measurements Of Reactive Nitrogen Compounds From Three California Cities, Gary A. Bishop, Allison Peddle, Donald H. Stedman Jan 2010

On-Road Emission Measurements Of Reactive Nitrogen Compounds From Three California Cities, Gary A. Bishop, Allison Peddle, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

The three California cities of San Jose, Fresno and West Los Angeles (wLA) were visited during March 2008 to collect on-road emission measurements of reactive nitrogen compounds from light-duty vehicles. At the San Jose and wLA sites comparison with historical measurements showed that emissions of carbon monoxide (CO), hydrocarbons (HC) and nitric oxide (NO) continue to decrease in the on-road fleet yet the ratio of nitrogen dioxide (NO2) to NO in new diesel vehicles appears to be under going large increases. A small fleet of 2007 diesel ambulances measured in Fresno was found to have more than 60% …