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Full-Text Articles in Chemistry

Comparison Of Upper Tropospheric Carbon Monoxide From Mopitt, Ace-Fts, And Hippo-Qcls, Sara Martínez-Alonzo, Merritt N. Deeter, Helen M. Worden, John C. Gille, Louisa K. Emmons, Laura L. Pan, Mijeong Park, Gloria L. Manney, Peter F. Bernath, Chris D. Boone Dec 2014

Comparison Of Upper Tropospheric Carbon Monoxide From Mopitt, Ace-Fts, And Hippo-Qcls, Sara Martínez-Alonzo, Merritt N. Deeter, Helen M. Worden, John C. Gille, Louisa K. Emmons, Laura L. Pan, Mijeong Park, Gloria L. Manney, Peter F. Bernath, Chris D. Boone

Chemistry & Biochemistry Faculty Publications

Products from the Measurements Of Pollution In The Troposphere (MOPITT) instrument are regularly validated using in situ airborne measurements. However, few of these measurements reach into the upper troposphere, thus hindering MOPITT validation in that region. Here we evaluate upper tropospheric (~500 hPa to the tropopause) MOPITT CO profiles by comparing them to satellite Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS) retrievals and to measurements from the High-performance Instrumented Airborne Platform for Environmental Research Pole to Pole Observations (HIPPO) Quantum Cascade Laser Spectrometer (QCLS). Direct comparison of colocated v5 MOPITT thermal infrared-only retrievals, v3.0 ACE-FTS retrievals, and HIPPO-QCLS measurements shows …


Optical Properties Of Secondary Organic Aerosols, Felisha Imholt, Ryan Caylor, Matthew E. Wise, John Shilling Oct 2014

Optical Properties Of Secondary Organic Aerosols, Felisha Imholt, Ryan Caylor, Matthew E. Wise, John Shilling

Matthew E. Wise

It is well known that the increased warming effect due to greenhouse gases is a major environmental concern. While the amount of solar radiation absorbed by greenhouse gases is known to a high certainty, the amount absorbed by secondary organic aerosols (SOA) is not. The experimental procedure used to measure the amount of radiation absorbed by SOA was optimized using fulvic acid. The optimized method was then used to measure how much radiation SOA absorb between ~200 and 800 nm. Using this data, mass absorption coefficient (MAC) values at 405 nm and imaginary refractive indexes (k) were calculated. These values …


Laser Intensity And Ionic Strength Dependence Of The Aqueous Nitrate And Carbonate Ion Raman Spectra, Samuel White May 2014

Laser Intensity And Ionic Strength Dependence Of The Aqueous Nitrate And Carbonate Ion Raman Spectra, Samuel White

Mahurin Honors College Capstone Experience/Thesis Projects

The geometry (and hence vibrational modes) of aqueous nitrate ion, NO3-, is known to depend on the solution composition—concentration, counter ions, etc. If a definite relationship between the vibrational spectrum and ionic strength of the solution could be established, it could be a useful monitor of solution composition over time. This would be valuable in studying the reaction rates and mechanisms of reactions involving nitrate in an aqueous environment, such as its photolysis in snow. Previous work in our lab observed a split peak at the symmetric-stretch mode of nitrate, though this mode does not usually show …


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.


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.


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.


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.


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 …


Spatial And Seasonal Variability Of Cloud Condensation Nuclei Number Concentrations Over The Extended North African Continent And The Mediterranean, Hesham Abdel-Monem Afify Hassan Jan 2014

Spatial And Seasonal Variability Of Cloud Condensation Nuclei Number Concentrations Over The Extended North African Continent And The Mediterranean, Hesham Abdel-Monem Afify Hassan

Legacy Theses & Dissertations (2009 - 2024)

The spatiotemporal variability of cloud condensation nuclei (CCN) number concentration is investigated over the extended domain of the North African continent and Mediterranean which is an essential step for better understanding of aerosol-cloud interactions and associated climate impacts over the region. The study is performed by analyzing the output for the period from 2004 to 2011 from the well-validated global chemistry and aerosol transport model GEOS-Chem-APM. The analysis shows that the dominant aerosol type for CCN number concentration is secondary particles all over the domain. Spatial analysis reveals the existence of four characteristic subdomains of variability: over the Mediterranean and …