Environmental Chemistry Commons^™

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) NO_x 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 NO_x emission factors from 1,591 HDV at a Utah Port of Entry in December 2020 that includes individual vehicle identification. In general, the NO_x 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) NO_x emission factors are similar …

The Art Of Poetry And Its Place In The History Of The Coordinating Research Councils Real World Emissions Workshop {Poster}, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

No abstract provided.

On-Road Vehicle Emission Measurements And Their Use In Evaluating Emission Control Effectiveness {Presentation}, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

No abstract provided.

On-Road Nox Emissions Evaluation Of The Repair Effectiveness For Recalled Volkswagen Group Light-Duty Diesel Vehicles In The United States, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

The admission by the Volkswagen Group in the fall of 2015 that they had duped the United States new vehicle emissions certification testing resulted in perhaps the most expensive violation of U.S. environmental vehicle emission regulations in its history. As part of the subsequent recall of more than 500,000 vehicles in the U.S., owners could sell their vehicles back to the companies or have them repaired. We have used a number of large on-road emission measurement data sets that were routinely collected before and after the recall to evaluate the fuel specific NO_x emissions benefit for the vehicles that …

Does California’S Emfac2017 Vehicle Emissions Model Under-Predict California Light-Duty Gasoline Vehicle Nox Emissions?, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

On-road remote sensing measurements of light and medium-duty gasoline vehicles collected within California’s South Coast Air Basin since 1999 generally fall within the range of observed summer ambient molar NO_x/CO measurements collected during morning rush hours. Compared with ambient and on-road emissions, the California Air Resources Board EMFAC model under predicts 2018 gasoline vehicle NO_x emission factors by more than a factor of 2.6. Contributing to these differences is that vehicles older than model year 2006 have NO_x emission deterioration rates that are up to 4 time’s higher on-road than predicted by the EMFAC model. A …

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 Automobile Emissions In The Chicago Area: Fall 2020, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

No abstract provided.

Investigation Of Emissions And Chemistry Of Formic Acid And Acetic Acid In Wildfire Smoke, Catherine Elizabeth Wielgasz

Graduate Student Theses, Dissertations, & Professional Papers

Formic acid (HCOOH) and acetic acid (CH₃COOH) are two of the most ubiquitous organic acids in the atmosphere. Chemical transport models consistently underestimate HCOOH and CH₃COOH concentrations in environments including fire smoke, implying our incomplete understanding of their global budget. Emissions and secondary production of HCOOH and CH₃COOH within complex mixtures in fire smoke is uncertain.

I used measurements from the NSF/NCAR C-130 aircraft during the Western Wildfire Experiment for Cloud Chemistry, Aerosol Absorption, and Nitrogen (WE-CAN) campaign to investigate emissions and photochemical production of HCOOH and CH₃COOH from smoke plumes. First, …

On-Road Remote Sensing Of Automobile Emissions In The Fresno, Ca Area: Spring 2021, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

No abstract provided.

Are Electric Vehicles A Panacea For Reducing Ozone Precursor Emissions?, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

No abstract provided.

On-Road Remote Sensing Of Automobile Emissions In The Denver Area: Winter 2020, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

No abstract provided.

On-Road Remote Sensing Of Automobile Emissions In The Tulsa Area: Fall 2019, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

No abstract provided.

Vehicle Exhaust Remote Sensing Device Method To Screen Vehicles For Evaporative Running Loss Emissions, Gary A. Bishop, Timothy H. Defries, James A. Sidebottom, James M. Kemper

Fuel Efficiency Automobile Test Publications

Vehicle hydrocarbon (HC) emissions can be emitted from either tailpipe or non-tailpipe locations and understanding their fleet apportionment is important for successful air pollution policy. Vehicles initially misidentified as having elevated tailpipe HC emissions first indicated that roadside exhaust sensors could detect the presence of evaporative HC emissions as increased noise in the HC/carbon dioxide (CO₂) correlation measurement. The 90^th percentile of the largest residual of the HC/CO₂ correlation is defined as a running loss index (RLI) for each measurement. An RLI that is three standard deviations or greater above the instruments noise indicates possible evaporative …

Inspection And Maintenance Evaluation Using Historical U.S. Remote Sensing Measurements, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

No abstract provided.

Our Energy Future, Fall/Winter 2007, Issue 15

Sustain Magazine

No abstract provided.

Renewable Energy, Fall/Winter 2011, Issue 23

Sustain Magazine

No abstract provided.

Active Transportation, Spring/Summer 2012, Issue 26

Sustain Magazine

No abstract provided.

Sustainable Behavior, Spring/Summer 2013, Issue 28

Sustain Magazine

No abstract provided.

Campus Sustainability, Spring/Summer 2014, Issue 30

Sustain Magazine

No abstract provided.

Carbon Neutral, Spring/Summer 2018, Issue 38

Sustain Magazine

No abstract provided.

Three Decades Of On-Road Mobile Source Emissions Reductions In South Los Angeles, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

In May of 2018, the University of Denver repeated on-road optical remote sensing measurements at two locations in Lynwood, CA. Lynwood area vehicle tailpipe emissions were first surveyed in 1989 and 1991 because the area suffered with a large number of carbon monoxide (CO) air quality violations. These new measurements allow for the estimation of fuel specific CO and total hydrocarbon (HC) emissions reductions, changes in the longevity of emission-control components, and the prevalence of high emitters in the current fleet.

Since 1989 CO emissions decreased approximately factors of 10 (120 ± 8 to 12.3 ± 0.2 gCO/kg of fuel) …

Measuring Emissions From The On-Road Vehicle Fleet In West Los Angeles, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

No abstract provided.

On-Road Remote Sensing Of Automobile Emissions In The Chicago Area: Fall 2018, 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

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 (NO_x) 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 …

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.

Revisit Lynwood, Ca: On-Road Remote Sensing Of Automobile Emissions In The Lynwood, Ca: 2018, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

No abstract provided.

Investigate The Durability Of Diesel Engine Emission Controls, Gary A. Bishop, Molly J. Haugen

Fuel Efficiency Automobile Test Publications

No abstract provided.

On-Road Remote Sensing Of Automobile Emissions In The Tulsa Area: Fall 2017, Gary A. Bishop

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

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 (NO_x) emissions of this fleet have increased and NO_x after-treatment systems do not appear to perform ideally in this …

On-Road Remote Sensing Of Automobile Emissions In The Denver Area: Winter 2017, Gary A. Bishop, Molly J. Haugen

Fuel Efficiency Automobile Test Publications

No abstract provided.