Center for Aerosol Science and Engineering (CASE)

CASE Research Spotlight: Investigation Of Thermal Radiation Under Pressurized Oxy-Combustion Conditions Thermal radiation of the gaseous and particle phases in a pilot-scale pressurized oxy-combustor is computationally studied. In particular, the radiation characteristics of gases and particles are estimated by employing the statistical narrow-band model and the large-particle model. It is found that thermal radiation of the particle cloud dominates in the combustor under a furnace temperature of 1500 K and when there is no substantial loss of particles to the walls. Another important observation is that radiation from the gas and particles can be approximately treated as a graybody under these conditions. More specifically, the results on the spectral radiation intensity of a gas comprising 40% (vol) H2O and 60% CO2 show that when the pressure is increased to 15 bar, and the radiation pathlength is 100 cm, the spectral radiation profile of the gas phase approaches that of a blackbody at the respective temperature. In addition, the emissivity of the particulate cloud has been evaluated as a function of the particle concentration and diameter by employing the large-particle model. It is shown that the emissivity grows with the particle concentration but decreases with the particle size for the same mass of the particles. This outcome of the present study is expected to be used to validate the assumption of the gray-gas model adopted in the numerical simulations of pressurized oxy-combustion. Lead Author and Corresponding Author: Lei Li is a doctoral researcher at West Virginia University (WVU). Co-Authors: Dr. V'yacheslav (Slava) Akkerman is a professor at WVU. Dr. Duarte Magalhaes is a research scientist at Washington University in St. Louis (WashU). Dr. Zhiwei Yang is a senior process engineer at Cabot Corporation. This research was conducted when Dr. Yang was working as a research scientist at WashU Energy, Environmental & Chemical Engineering (EECE). Dr. Richard Axelbaum is a professor of the Center for Aerosol Science and Engineering (CASE) and the Consortium for Clean Coal Utilization, Washington University McKelvey School of Engineering. Learn more: https://lnkd.in/gnCBRDkY #Aerosol #Science #Engineering #WUSTL #WashU #WashUEngineers #WashUEECE

CASE Research Spotlight: Chemical Fate of Oils on Indoor Surfaces: Ozonolysis and Peroxidation Unsaturated triglycerides found in food and skin oils are reactive in ambient air. However, the chemical fate of such compounds has not been well characterized in genuine indoor environments. Here, we monitored the aging of oil coatings on glass surfaces over a range of environmental conditions, using mass spectrometry, nuclear magnetic resonance (NMR), and electron paramagnetic resonance (EPR) techniques. Upon room air exposure (up to 17 ppb ozone), the characteristic ozonolysis products, secondary ozonides, were observed on surfaces near the cooking area of a commercial kitchen, along with condensed-phase aldehydes. In an office setting, ozonolysis is also the dominant degradation pathway for oil films exposed to air. However, for indoor enclosed spaces such as drawers, the depleted air flow makes lipid autoxidation more favorable after an induction period of a few days. Forming hydroperoxides as the major primary products, this radical-mediated peroxidation behavior is accelerated by indoor direct sunlight, but the initiation step in dark settings is still unclear. These results are in accord with radical measurements, indicating that indoor photooxidation facilitates radical formation on surfaces. Overall, many intermediate and end products observed are reactive oxygen species (ROS) that may induce oxidative stress in human bodies. Given that these species can be widely found on both food and household surfaces, their toxicological properties are worth further attention. Lead Author and Corresponding Author: Dr. Zilin Zhou is a research scientist at Health Canada | Santé Canada. Co-Authors: Dr. Leigh Crilley is an associate air quality consultant at WSP in Australia. Dr. Jenna Ditto is an assistant professor at Washington University in St. Louis (WashU) and the Center for Aerosol Science and Engineering (CASE), Washington University McKelvey School of Engineering. This research was conducted when Dr. Ditto worked as a postdoctoral researcher at University of Toronto right before formally joining WashU Energy, Environmental & Chemical Engineering (EECE). Dr. Trevor VandenBoer is an associate professor at York University. Corresponding Author: Dr. Jonathan Abbatt is a professor in the Department of Chemistry at the University of Toronto. Learn more: https://lnkd.in/g3hF9Gh2 #Aerosol #Science #Engineering #WUSTL #WashU #WashUEngineers #WashUEECE

CASE Research Spotlight: Optical Properties of Fine Mode Aerosols over High-Altitude Himalayan Glacier Regions During the summer and winter periods of 2019–2020, we conducted sampling of fine mode ambient aerosols in the western Himalayan glacial region (WHR; Thajiwas glacier, 2799 m asl), central Himalayan glacial region (CHR; Gomukh glacier, 3415 m asl), and eastern Himalayan glacial region (EHR; Zemu glacier, 2700 m asl). We observed the highest absorption in the near ultraviolet–visible wavelength range (200–400 nm), with CHR showing the highest absorption compared to the other two sites, WHR and EHR, respectively. Across the wavelength range of 200–1100 nm, the overall contribution of black carbon to light attenuation was greater than that of brown carbon. However, brown carbon dominated the absorption in the near UV–visible wavelengths, providing evidence of its non-trivial presence over the Himalayan region. Additionally, we observed a positive radiative forcing (W/g), which leads to net warming at these sites. The findings of this ground-based study contribute to our understanding of the light-absorbing nature of carbonaceous aerosols and their impact on the Himalayan glacier regions. Lead Author: Dr. Sushant Ranjan Verma is a researcher at Pt. Ravishankar Shukla University (PRSU). Co-Authors: Dr. Judith Chow and Dr. John Watson are research professors at Desert Research Institute (DRI). Dr. Syed Muzaffar Andrabi is a professor at University of Kashmir. Dr. Papiya Mandal is a principal scientist at National Environmental Engineering Research Institute (NEERI), Council of Scientific and Industrial Research (CSIR). Dr. Noor A Khan is also a principal scientist at CSIR- National Environmental Engineering Research Institute. Dr. Suresh Tiwari is a retired scientist from Indian Institute of Tropical Meteorology. Dr. Umesh Dumka is a research scientist at Aryabhatta Research Institute of Observational Sciences (ARIES). Dr. Rajan Chakrabarty is a professor at Washington University in St. Louis (WashU), conducting research at WashU Energy, Environmental & Chemical Engineering (EECE) and the Center for Aerosol Science and Engineering (CASE), Washington University McKelvey School of Engineering. Dr. Yasmeen Fatima Pervez is an assistant professor at Govt. Dr. Waman Wasudev Patankar Girls PG College. Dr. Hulivahana Nagaraju Sowmya is an associate professor at Dayananda Sagar College of Engineering, BANGALORE. Other co-authors include Dr. Madhuri Verma, Archi Mishra, Aishwaryashri Tamrakar, Dr. Manas Kanti Deb, Dr. KALLOL KUMAR GHOSH, Dr. Indrapal Karbhal, Dr. Kamlesh Shrivas, and Dr. Manmohan Satnami, all from PRSU, and Vikas Kumar Jain from the Ministry of Skill Development, Technical Education and Employment. Corresponding Author: Dr. shamsh pervez is a professor at PRSU. Learn more: https://lnkd.in/gGgrHukZ #Aerosol #Science #Engineering #WUSTL #WashU #WashUEngineers #WashUEECE

CASE Dissertation Spotlight: Understanding the Relationship Between PM2.5 and Aerosol Optical Depth (AOD) Featured Researcher: Dr. Haihui Zhu owns a B.S. degree in environmental science from Sun Yat-sen University, a M.E. degree in civil and environmental engineering from Louisiana State University, and a Ph.D. in energy, environmental and chemical engineering from Washington University in St. Louis (WashU), with experiences of internship at ThriveLink and consulting at The BALSA Group. As a doctoral researcher in the Atmospheric Chemistry and Analysis Group at WashU Energy, Environmental & Chemical Engineering (EECE) and the Center for Aerosol Science and Engineering (CASE), Washington University McKelvey School of Engineering, Haihui used the GEOS-Chem model, ground-based aerosol measurement, and satellite remote sensing data to explore the relationship between global scale PM2.5 and AOD, aerosol size representation, and emission uncertainties. Dr. Zhu is now a postdoctoral researcher at Colorado State University. Committee Members: Dr. Randall Martin, Dr. Jeffrey Pierce, Dr. Jay Turner, Dr. Jian Wang, and Dr. Lu Xu. #Aerosol #Science #Engineering #WUSTL #WashU #WashUEngineers #WashUEECE

CASE Research Spotlight: O3 Sensitivity to NOx and VOC During RECAP-CA: Implication for Emissions Control Strategies We used two parallel transportable smog chamber systems to measure the sensitivity of ozone (O3) to volatile organic compounds (VOCs) and nitrogen oxides (NOx = NO + NO2) in Pasadena and Redlands, California from July to October, 2021. The monthly median observed O3 sensitivity in Pasadena was stable in the VOC-limited regime, but showed a seasonal trend in Redlands, where median O3 sensitivity was VOC-limited in July and October and transitioned towards the NOx-limited regime in August and September. Day-specific O3 sensitivity at both Pasadena and Redlands could be either NOx-limited or VOC-limited on O3-nonattainment days. Calculated O3 isopleths for Pasadena and Redlands were constructed using a photochemical box model based on comprehensive measurements of NOx and VOCs during the Re-Evaluating the Chemistry of Air Pollutants in California (RECAP-CA) campaign. Calculated O3 isopleths were in good agreement with the chamber measurements. The calculations suggest that an additional ～40% NOx reduction is needed for Pasadena and Redlands to move 95% of the days with O3 concentrations above 70 ppb to the NOx-limited regime where further NOx reductions will result in lower O3 concentrations. Lead Author: Dr. Shenglun Wu is an air resources engineer at California Air Resources Board (CARB). This research was conducted when Dr. Wu worked as a doctoral researcher at University of California, Davis (UC Davis). Co-Authors: Other co-authors from UC Davis include Christopher P. Alaimo, Yusheng Zhao, Peter Green, and Thomas Young. Dr. Toshihiro Kuwayama is an air resources supervisor at CARB. Dr. Shang Liu is an assistant professor at Northeastern University. This research was conducted when Dr. Liu worked as an air resources engineer at CARB. Dr. Matthew M. Coggon, Dr. Chelsea Stockwell, Dr. Carsten Warneke, Dr. Jessica B. Gilman, Dr. Michael A. Robinson are research scientists at NOAA: National Oceanic & Atmospheric Administration. Dr. Lu Xu is an assistant professor at Washington University in St. Louis (WashU) and the Center for Aerosol Science and Engineering (CASE), Washington University McKelvey School of Engineering. This research was conducted when Dr. Xu worked as a research scientist at NOAA right before formally joining WashU Energy, Environmental & Chemical Engineering (EECE). Dr. Patrick Veres is a research scientist at NSF NCAR Earth Observing Laboratory. This research was conducted when Dr. Veres worked as a research scientist at NOAA. Dr. J. Andrew Neuman is a retired research scientist from NOAA. Corresponding Author: Dr. Michael J. Kleeman is a professor at UC Davis Department of Civil & Environmental Engineering. Learn more: https://lnkd.in/gPqx5wZa #Aerosol #Science #Engineering #WUSTL #WashU #WashUEngineers #WashUEECE

CASE Research Spotlight: The kinetics and warm flame chemistry associated with radiative extinction of spherical diffusion flames Several studies have found that microgravity diffusion flames with sufficient heat loss cool until they extinguish at a critical temperature near 1130?K. In this work, the associated chemical kinetics are explored for spherical diffusion flames burning ethylene. The flames are simulated with a transient numerical model with detailed chemistry, transport, and radiation. This incorporates the UCSD mechanism with 57 species and 270 reactions. Species concentrations, reaction rates, and heat release rates are examined. Upon ignition, the peak temperature is above 2000 K, but this decreases until extinction due to radiative losses. This allows the chemistry to be studied over a wide range of peak temperatures for the same fuel and oxidiser. When the peak temperature is high, the dominant chemistry is similar to that for typical normal-gravity ethylene diffusion flames. There are two distinct zones: an ethylene pyrolysis zone and an oxidation zone, and negligible reactant leakage. The ethylene mainly reacts with H and OH. The concentration of OH in the ethylene pyrolysis zone is high due to the long residence times and reactions of CO2 and H2O with H. As the flame cools and the peak temperature approaches the critical extinction temperature, there is increased reactant leakage leading to higher O, OH, and HO2 concentrations on the fuel side. Most reactions shift towards the oxidiser side and there is large overlap between the two zones. Reactions involving HO2 become more significant and the large consumption rates of H by HO2 increase the concentrations of OH and O on the fuel side. The appearance of warm flame chemistry delays extinction but is not sufficiently exothermic to prevent it. Lead Author: Dr. Kendyl Waddell is a postdoctoral researcher at NASA Glenn Research Center. This research was conducted when Dr. Waddell worked as a doctoral researcher at University of Maryland (UMD). Co-Authors: Phillip Irace, Ph.D., P.E. is a program director at the International Space Station National Laboratory. This research was conducted when Dr. Irace worked as a doctoral researcher at Washington University in St. Louis (WashU). Dr. Gregory Yablonsky is an adjunct professor at WashU Energy, Environmental & Chemical Engineering (EECE). Dr. Denis Constales is an associate professor at Ghent University. Dr. Richard Axelbaum is a professor at WashU EECE and the Center for Aerosol Science and Engineering (CASE), Washington University McKelvey School of Engineering. Corresponding Author: Dr. Peter Sunderland is a professor in the Department of Fire Protection Engineering at UMD. Learn more: https://lnkd.in/gNcyY9KT #Aerosol #Science #Engineering #WUSTL #WashU #WashUEngineers #WashUEECE

CASE Research Spotlight: Examining the vertical heterogeneity of aerosols over the Southern Great Plains Atmospheric aerosols affect the global energy budget by scattering and absorbing sunlight (direct effects) and by changing the microphysical structure, lifetime, and coverage of clouds (indirect effects). Both aerosol direct and indirect effects are affected by the vertical distribution of aerosols in the atmosphere, which is further influenced by a range of processes, such as aerosol dynamics, long-range transport, and entrainment. However, many observations of these processes are based on ground measurements, limiting our ability to understand the vertical distribution of aerosols and simulate their impact on clouds and climate. In this work, we examined the vertical heterogeneity of aerosols over the Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) using data collected from the Holistic Interactions of Shallow Clouds, Aerosols and Land Ecosystems (HI-SCALE) campaign. The vertical profiles of meteorological and aerosol physiochemical properties up to 2500?m above are examined based on the 38 flights conducted during the HI-SCALE campaign. Lead Author and Corresponding Author: Dr. Yang Wang is an assistant professor at University of Miami. Co-Authors: Chanakya Bagya Ramesh is a doctoral researcher at Missouri University of Science and Technology (Missouri S&T) and University of Miami Department of Chemical, Environmental & Materials Engineering (CEME). Dr. Scott Giangrande is a meteorologist at Brookhaven National Laboratory (BNL). Dr. Jerome Fast is a staff scientist from Battelle and a fellow at Pacific Northwest National Laboratory (PNNL). Dr. Xianda Gong is an assistant professor at Westlake University. Dr. Jiaoshi Zhang is a staff scientist at Washington University in St. Louis (WashU). This research was conducted when Dr. Gong and Dr. Zhang worked as postdoctoral researchers at WashU Energy, Environmental & Chemical Engineering (EECE) and the Center for Aerosol Science and Engineering (CASE), Washington University McKelvey School of Engineering. Tolga Odabasi is an atomic energy assistant specialist at Türkiye Enerji, Nükleer ve Maden Ara?t?rma Kurumu. This research was conducted when Tolga worked as a graduate researcher at Missouri S&T Civil, Architectural and Environmental Engineering. Marcus Batista is a doctoral researcher from the CEME Department at University of Miami College of Engineering. Alyssa Matthews is a radar data analyst, Dr. Fan Mei is a an earth scientist, Dr. John Shilling is a chemist, and Dr. Jason Tomlinson is an atmospheric scientist, all from PNNL. Dr. Dié Wang is an assistant atmospheric scientist from BNL. Dr. Jian Wang is a professor at WashU EECE and CASE. Learn more: https://lnkd.in/gAN_6-xp #Aerosol #Science #Engineering #WUSTL #WashU #WashUEngineers #WashUEECE

CASE Dissertation Spotlight: Aerosol Technology for Carbon Capture and Utilization Featured Researcher: Dr. Onochie Okonkwo is a chemical engineer with the background of a Bachelor of Technology in chemical engineering from Rivers State University of Science and Technology and an M.S. in gas, petroleum refining and petrochemicals from?University of Port Harcourt Nigeria, and substantial experiences in industries, including Nigeria Liquefied Natural Gas (NLNG), Federal Government of Nigeria, Nigerian Bottling Company Plc (now Coca-Cola HBC), Engineers India Limited, Bharat Petroleum Corporation Limited, and Dangote Industries Limited. Before obtaining an M.S. and a Ph.D. in energy, environmental and chemical engineering from Washington University in St. Louis (WashU), Onochie gained even more experiences from InSITE and NanoGuard Technologies Inc. as a doctoral researcher of the Aerosol and Air Quality Research Laboratory (AAQRL) at WashU Energy, Environmental & Chemical Engineering (EECE), and the Center for Aerosol Science and Engineering (CASE), Washington University McKelvey School of Engineering, and worked as a research assistant at University of Miami Department of Chemical, Environmental & Materials Engineering and the Center for Aerosol Science and Technology (CAST) after AAQRL relocated to University of Miami, focusing on aerosol technology as an enabler for pressurized oxy-combustion carbon capture and the synthesis of catalysts for carbon utilization. Onochie's research work includes designing and fabricating a pressurized drop tube furnace experiment system to advance research on particle formation mechanisms in pressurized combustion conditions and carrying out the process characterization of the spray flame aerosol reactor for catalyst synthesis and design. Dr. Okonkwo has the expertise and is seeking opportunities to develop and scale up novel clean sustainable process technologies. Committee Members: Dr. Pratim Biswas, Dr. Ravindra Gudi, Dr. Rajan Chakrabarty, Dr. Benjamin Kumfer, Dr. Vijay Ramani, Dr. Carmo Pereira, and Dr. Gregory Yablonsky. #Aerosol #Science #Engineering #WUSTL #WashU #WashUEngineers #WashUEECE

CASE Research Spotlight: Plasma mineral status after a six-month intervention providing one egg per day to young Malawian children: a randomized controlled trial Mineral deficiencies are common in children living in low-resource areas. Eggs are a rich source of essential nutrients and have been shown to improve growth in young children, although little is known about their impact on mineral status. Children aged 6–9 months (n?=?660) were randomized to receive either one egg/day for 6-months or no intervention. Anthropometric data, dietary recalls, and venous blood were collected at baseline and 6-months follow-up. Quantification of plasma minerals (n?=?387) was done using inductively coupled plasma-mass spectroscopy. Difference-in-difference mean plasma mineral concentrations was determined from baseline and follow-up values and assessed between groups by intention-to-treat using ANCOVA regression models. Prevalence of zinc deficiency was 57.4% at baseline and 60.5% at follow-up. Mean difference (MD) of plasma magnesium, selenium, copper, and zinc levels were not different between groups. Plasma iron concentrations were significantly lower in the intervention compared to the control group (MD?=???9.29; 95% CI: ??15.95, ??2.64). Zinc deficiency was widely prevalent in this population. Mineral deficiencies were not addressed with the egg intervention. Further interventions are needed to improve the mineral status of young children. Lead Author: Marina Perez-Plazola is a researcher at Washington University in St. Louis (WashU). Co-Authors: Dr. Christine Stewart is a professor, Charles D Arnold is a statistician, and Emmanuel A. Gyimah, MPH is a doctoral researcher, all from University of California, Davis. Dr. Bess Caswell is a research nutritionist at US Department of Agriculture (USDA) Agricultural Research Service (ARS). Dr. Chessa Lutter is a senior fellow at RTI International. Rochelle Werner, PhD, RDN is a postdoctoral researcher at Emory University. Dr. Ken Maleta is a professor at Kamuzu University of Health Sciences. Dr. Jay Turner is a professor at WashU Energy, Environmental & Chemical Engineering (EECE) and the Center for Aerosol Science and Engineering (CASE), Washington University McKelvey School of Engineering. Pradeep Prathibha, PhD is a postdoctoral researcher at U.S. Department of Energy (DOE) supported by American Association for the Advancement of Science (AAAS) AAAS Science & Technology Policy Fellowships. Dr. Xuan Liu is a postdoctoral researcher from Scripps Institution of Oceanography at UC San Diego. Dr. Lora Iannotti is a professor at WashU Brown School and the Institute for Public Health. Corresponding Author: Dr. Jenna Diaz is a pediatric gastroenterologist of Washington University School of Medicine in St. Louis. Learn more: https://lnkd.in/g6dsjh9g #Aerosol #Science #Engineering #WUSTL #WashU #WashUEngineers #WashUEECE

CASE Event Spotlight: American Meteorological Society (AMS) 105th Annual Meeting The Center for Aerosol Science and Engineering (CASE), Washington University McKelvey School of Engineering is a world leader in aerosol science at Washington University in St. Louis (WashU), with core members from WashU Energy, Environmental & Chemical Engineering (EECE) and affiliated members from other departments. Last week, researchers from WashU EECE and CASE played different roles in the AMS 105th Annual Meeting, including presenter, poster judge, student volunteer, and co-author of presentations with recent research findings. Featured Presentations: 1. Stratospheric air intrusions promote global-scale new particle formation (presented by Jiaoshi Zhang) 2. Improving Cooking and VCP Chemistry in WRF-Chem to More Confidently Quantify Co-Benefits of Zero-Emission Vehicle Adoption on CO2 Emissions and Air Pollutants in Los Angeles (presented by Rebecca Schwantes) 3. AERO-MAP: A data compilation and modelling approach to understand spatial variability in fine and coarse mode aerosol composition (presented by Natalie Mahowald) 4. Distributions and Correlations of Volatile Organic Compounds (VOCs) during AEROMMA 2023 over North America (presented by Victoria Treadaway) 5. Evaluating the emissions and chemistry of understudied VOC sources using observations from AEROMMA and recent ground campaigns (presented by Matthew Coggon) 6. Impact of Formaldehyde on Oxidant Production in the Greater Chicago Area (presented by Nidhi Desai) Featured CASE Researchers: Jhao-Hong Chen, Xianda Gong, Randall Martin, Brenna Walsh, Jian Wang, Crystal Weagle, Lu Xu, and Jiaoshi Zhang. #Aerosol #Science #Engineering #WUSTL #WashU #WashUEngineers #WashUEECE