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Articles 1 - 30 of 163
Full-Text Articles in 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 …
On-Road Vehicle Emission Measurements And Their Use In Evaluating Emission Control Effectiveness {Presentation}, Gary A. Bishop
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.
The Art Of Poetry And Its Place In The History Of The Coordinating Research Councils Real World Emissions Workshop {Poster}, Gary A. Bishop
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 Nox Emissions Evaluation Of The Repair Effectiveness For Recalled Volkswagen Group Light-Duty Diesel Vehicles In The United States, Gary A. Bishop
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 NOx emissions benefit for the vehicles that …
On-Road Remote Sensing Of Automobile Emissions In The Fresno, Ca Area: Spring 2021, Gary A. Bishop
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.
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 Automobile Emissions In The Chicago Area: Fall 2020, Gary A. Bishop
On-Road Remote Sensing Of Automobile Emissions In The Chicago Area: Fall 2020, Gary A. Bishop
Fuel Efficiency Automobile Test Publications
No abstract provided.
Does California’S Emfac2017 Vehicle Emissions Model Under-Predict California Light-Duty Gasoline Vehicle Nox Emissions?, Gary A. Bishop
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 NOx/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 NOx emission factors by more than a factor of 2.6. Contributing to these differences is that vehicles older than model year 2006 have NOx emission deterioration rates that are up to 4 time’s higher on-road than predicted by the EMFAC model. A …
Investigation Of Emissions And Chemistry Of Formic Acid And Acetic Acid In Wildfire Smoke, Catherine Elizabeth Wielgasz
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 Denver Area: Winter 2020, Gary A. Bishop
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
On-Road Remote Sensing Of Automobile Emissions In The Tulsa Area: Fall 2019, Gary A. Bishop
Fuel Efficiency Automobile Test Publications
No abstract provided.
Are Electric Vehicles A Panacea For Reducing Ozone Precursor Emissions?, Gary A. Bishop
Are Electric Vehicles A Panacea For Reducing Ozone Precursor Emissions?, 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
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 90th 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
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
Renewable Energy, Fall/Winter 2011, Issue 23
Active Transportation, Spring/Summer 2012, Issue 26
Active Transportation, Spring/Summer 2012, Issue 26
Sustain Magazine
No abstract provided.
Sustainable Behavior, Spring/Summer 2013, Issue 28
Sustainable Behavior, Spring/Summer 2013, Issue 28
Sustain Magazine
No abstract provided.
Campus Sustainability, Spring/Summer 2014, Issue 30
Campus Sustainability, Spring/Summer 2014, Issue 30
Sustain Magazine
No abstract provided.
Carbon Neutral, Spring/Summer 2018, Issue 38
On-Road Remote Sensing Of Automobile Emissions In The Chicago Area: Fall 2018, Gary A. Bishop
On-Road Remote Sensing Of Automobile Emissions In The Chicago Area: Fall 2018, Gary A. Bishop
Fuel Efficiency Automobile Test Publications
No abstract provided.
Measuring Emissions From The On-Road Vehicle Fleet In West Los Angeles, Gary A. Bishop
Measuring Emissions From The On-Road Vehicle Fleet In West Los Angeles, Gary A. Bishop
Fuel Efficiency Automobile Test Publications
No abstract provided.
Three Decades Of On-Road Mobile Source Emissions Reductions In South Los Angeles, Gary A. Bishop
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) …
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.
The Story Of Ever Diminishing Vehicle Tailpipe Emissions As Observed In The Chicago, Il Area, Gary A. Bishop, Molly J. Haugen
The Story Of Ever Diminishing Vehicle Tailpipe Emissions As Observed In The Chicago, Il Area, Gary A. Bishop, Molly J. Haugen
Fuel Efficiency Automobile Test Publications
The University of Denver has collected on-road fuel specific vehicle emissions measurements in the Chicago area since 1989. This nearly 30 year record illustrates the large reductions in light-duty vehicle tailpipe emissions and the remarkable improvements in emissions control durability to maintain low emissions over increasing periods of time. Since 1989 fuel specific carbon monoxide (CO) emissions have been reduced by an order of magnitude and hydrocarbon (HC) emissions by more than a factor of 20. Nitric oxide (NO) emissions have only been collected since 1997 but have seen reductions of 79%. This has increased the skewness of the emissions …
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 …
On-Road Remote Sensing Of Automobile Emissions In The Denver Area: Winter 2017, Gary A. Bishop, Molly J. Haugen
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.
Revisit Lynwood, Ca: On-Road Remote Sensing Of Automobile Emissions In The Lynwood, Ca: 2018, Gary A. Bishop
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.
On-Road Remote Sensing Of Automobile Emissions In The Tulsa Area: Fall 2017, Gary A. Bishop
On-Road Remote Sensing Of Automobile Emissions In The Tulsa Area: Fall 2017, 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
Investigate The Durability Of Diesel Engine Emission Controls, Gary A. Bishop, Molly J. Haugen
Fuel Efficiency Automobile Test Publications
No abstract provided.