Publications
Published Articles
Invited Talks
2011
119) Ayala, A. Zhang, S., Rieger, P., Kamboures, M., Yu, Y., Sandoval, J., Hu, S., Collins, J., Chang, O., and McMahon, W. Prospects for Low PM and Low Climate Impacts in Future Advanced Clean Cars for California. Proceedings of the 21 CRC Real World Emissions Workshop. San Diego, CA. March 20-23, 2011.
118) McMahon, W., Zhang, S., Ayala, A., Rieger, P., and Chang, O. Fuel and Technology Effects on Particulate Matter Emissions for Light-Duty Gasoline Vehicles. Proceedings of the 21 CRC Real World Emissions Workshop. San Diego, CA. March 20-23, 2011.
117) Ayala, A. Mader, P. Watson, J. A Brief Report on Global Harmonization of PM and Particle Number Test Procedures under a New UNECE Effort. Proceedings of the 21 CRC Real World Emissions Workshop. San Diego, CA. March 20-23, 2011.
116) Ayala, A. Mobile Source Emission Reductions for Meeting Climate and Clean Air Goals. Indo-US Workshop on Transportation and Greenhouse Gas Emissions. Central Road Research Institute. Feb. 10-11, 2011. New Delhi, INDIA.
2010
115) Ayala, A. Los vehículos de ultra-baja y zero emisiones para cumplir con las metas de aire limpio. Seminario Internacional de Transporte Sustentable. Dec. 7, 2010. Santiago, CHILE
114) Dwyer, H., Ayala, A., Zhang, S., Collins, J., Huai, T., Herner, J., and Chau, W. Emissions from a Euro 4 LDV with the European PMP with and without Regeneration. 2010 CRC Mobile Source Air Toxics Workshop, Nov. 30 – Dec. 2. Sacramento, CA.
113) Ayala, A. Mobile source emission reductions for meeting air quality and climate protection goals. Bay Area Environmental Research Institute. NASA Ames Research Center. Moffet Field, CA. Aug. 26, 2010.
112) Ayala, A. El marco del programa de control de emisiones de vehiculos ligeros en California. Taller Oportunidades para la Introduccion de Vehiculos Limpios y Competitivos en Colombia. Videoconferencia. July 7, 2010. Bogota, COLOMBIA.
111) Ayala, A., “Las Estrategias para el Control de Emisiones a Diesel en California,” Seminario Internacional: Estrategias para mejorar la calidad del aire en el Valle de Aburra, June 3-4, 2010, Medellin, COLOMBIA
110) Ayala, A., “Rumbo al zero: el Programa Low Emission Vehicle (LEV) de California,” Seminario Internacional: Estrategias para mejorar la calidad del aire en el Valle de Aburra, June 3-4, 2010, Medellin, COLOMBIA
109) Ayala, A., “Mobile source emission reduction for meeting environmental goals,” Plenary Lecture, Air Pollution and Health: Bridging the Gap from Sources to Health Outcomes, American Association for Aerosol Research Specialty Conference, San Diego, California, March 22-26, 2010
108) Hu, S., Herner, J., Huai, T., Collins, J., and Ayala, A., “Diesel emission characterization and control: quantifying source-specific pollution of toxicological relevance,” Platform Presentation, Air Pollution and Health: Bridging the Gap from Sources to Health Outcomes, American Association for Aerosol Research Specialty Conference, San Diego, California, March 22-26, 2010
107) Hu, S., Herner, J., Robertson, W., Chang, M., Huai, T., Collins, J., Dwyer, H.., and Ayala, A., “Urea-based Selective Catalytic Reduction (SCR) for HDDVs: Chemistry, Physics, and Toxicology of Emissions,” Proceedings of the 20th CRC On-Road Vehicle Emissions Workshop, San Diego, CA, March 22-24, 2010.
106) Dwyer, H.., Ayala, A., Zhang, S., Collins, J., Huai, T., Herner, J., and Chau, W., “Emissions from the PMP Diesel Car during Regeneration,” Proceedings of the 20th CRC On-Road Vehicle Emissions Workshop, San Diego, CA, March 22-24, 2010.
105) Hu, S., Herner, J., Robertson, W., Change, M., Huai, T., Collins, J., Dwyer, H., and Ayala, A., “Characterization of a Non-Catalyzed, Electrically Heated DPF: Performance and Emission Control,” Proceedings of the 20th CRC On-Road Vehicle Emissions Workshop, San Diego, CA, March 22-24, 2010.
104) Ayala, A., and Motallebi, N., “Relevance of Black Carbon Particle Pollution for California’s Climate Protection Efforts,” Proceedings of the 20th CRC On-Road Vehicle Emissions Workshop, San Diego, CA, March 22-24, 2010.
103) Motallebi, N. and Ayala, A., “The Success of Air Pollution Controls in California,” Proceedings of the 20th CRC On-Road Vehicle Emissions Workshop, San Diego, CA, March 22-24, 2010.
102) Ayala, A., Motallebi, N., and Hu, S., “Diesel Emission Research for Informing Air Quality and Climate Policy in California,” Presentation at the AVL 6th International Exhaust Gas and Particulate Emissions Forum, 9-10 March 2010, Ludwigsburg, GERMANY
2009
100) Ayala, A., “Diesel Emission Characterization and Control,” Invited Seminar, Fall Colloquia, Atmospheric Sciences Department, University of Illinois at Urbana-Champaign, Nov. 4, 2009.
99) Overdier, J., Shafer, M., Toner, B., Schauer, J., Herner, J., and Ayala, A., “Chemical Speciation of Vanadium in Aerosol Particulate Matter (PM),” 28th American Association for Aerosol Research Annual Conference, Minneapolis, Minnesota, Oct 26-30, 2009.
98) Lee, S., Riemer, N., West, M., Zaveri, R.A., Morore, K., Sioutas, C., Delfino, R., Ayala, A., Sax, T., and Stanier, C., “Near-Road Size-Resolved Aersol and Gas Concentrations: Development of a Hybrid Dispersion and Aerosol Dynamics Model with Evaluation against Ambient Measurements,” 28th AAAR Annual Conference, Minneapolis, Minnesota, Oct 26-30, 2009.
97) Ayala, A. Chen, J., and Motallebi, N., “Black carbon controls in California: emissions, abatement, and knowledge gaps, 2009 International Workshop on Black Carbon in Latin America, October 19, 2009, Mexico City, MEXICO.
96) Ayala, A., “Overview of California Activities for Climate Protection and Air Quality Improvement,” SEMTECH Users’ Network (SUN) Conference, Ann Arbor, 24-25 September 2009.
95) Dwyer, H., Ayala, A., Zhang, S., Collins, J., Huai, T., Herner, J., and Chau, W., “Measurements of Emissions from a Diesel Car during Regeneration of an Active DPF,” Proceedings of the 15th Directions in Engine-Efficiency and Emissions Research (DEER) Conference, Dearborn, Michigan, August 2009.
94) Hu, S., Herner, J., Robertson, W., Chang, O., Huai, T., Collins, J., Dwyer, H., and Ayala, A., :Effects of Catalysts on Emissions from Heavy-Duty Diesel Retrofits for PM and NOx Control,” Proceedings of the 15th Directions in Engine-Efficiency and Emissions Research (DEER) Conference, Dearborn, Michigan, August 2009.
93) Ayala, A., Hu, S., Dwyer, H., Collins, J., Huai, T., and Herner, J., “Regeneration, volatile nanoparticles, toxicity and other research questions for diesel emission control,” Proceedings of the 13th ETH Conference on Combustion Generated Particles, Zurich, SWITZERLAND, June 2009.
92) Ayala, A., “California’s Greenhouse Gas Emission Management Policy Portfolio,” West Virginia Science and Technology Research Symposium, Charleston, April 14, 2009
91) Ayala, A., “California’s Greenhouse Gas Emission Management Policy Portfolio,” invited presentation to the United States Department of Energy Laboratory Energy R&D Working Group, Washington, D.C., April 15, 2009
90) Durbin, T.D., Okamoto, R., Johnson, K.C., Miller, J.W., Vergara, F., Sahay, K., Robertson, W., Guthrie, J., Chernich, P., Rieger, P., Chang, O., Pang, Y., Fuentes, M., Na, K., Maldonado, H., Bloudoff, D., Hu, S., Ayala, A., Sideco, A., Kado, N.Y., Kobayashi, R., Vogel, C.F.A., Cahill, T.M., Matsumura, F., and Wong, P.S., “Comprehensive Assessment of the Emissions from the Use of Biodiesel,” Proceedings of the 19th CRC On-Road Vehicle Emissions Workshop, San Diego, CA, March 23-25, 2009.
89) Cicero-Fernandez, P., Durbin, T.D., Zhang, M., Gutierrez, A., Huo, D., Vo, T., Collins, J.F., Huai, T., Gentala, R., Olson, M., Stover, C., and Saito, D., “Evaluation of High PM Emitting Light Duty Gasoline Vehicles and Potentail Repair Benefits: Preliminary Results,” Proceedings of the 19th CRC On-Road Vehicle Emissions Workshop, San Diego, CA, March 23-25, 2009.
88) Cicero-Fernandez, P., Zhang, M., Gutierrez, A., Collins, J.F., Huo, D., Vo, T., Huai, T., Susnowitz, R., Ayala, A., Durbin, T.D., Pisano, J.T., Saito, D., Olson, M., and Gentala, R., “Comparisons of Real-Time PM Instruments and Gravimetric Measurements on Light Duty Gasoline Vehicles,” Proceedings of the 19th CRC On-Road Vehicle Emissions Workshop, San Diego, CA, March 23-25, 2009.
87) Hu, S., Herner, J., Robertson, W., Chang, M.-C., Huai, T., Collins, J., and Ayala, A., “DPF + SCR Retrofits and their Impact on Diesel Emissions,” Proceedings of the 19th CRC On-Road Vehicle Emissions Workshop, San Diego, CA, March 23-25, 2009.
86) Ayala, A., “Perspectivas: el impacto sobre la calidad del aire y el cambio climatico global de la flota vehicular,” Conferencia Internacional - Revision Tecnica Vehicular: Herramienta Fundamental para la Gestion Ambiental y la Seguridad Vial, Febrero 4 y 5, 2009, Quito, ECUADOR
85) Ayala, A., “Reduccion de emisiones vehiculares: programas y tecnologias de transicion y perspectivas futuras,” Conferencia Internacional - Revision Tecnica Vehicular: Herramienta Fundamental para la Gestion Ambiental y la Seguridad Vial, Febrero 4 y 5, 2009, Quito, ECUADOR
2008
84) Hu, S., Herner, J., Robertson, W., Chang, M.-C. O., Huai, T., Collins, J, and Ayala, A. “Emissions from HD Diesel Retrofits for PM and NOX Control.” 2008 CRC Mobile Source Air Toxics Workshop, Phoenix, Arizona, December 1-3, 2008
83)Ayala, A., “Clean Air Targets for California – Diesel Emissions and Role of Research for Informing Policy,” Course on Ultrafine Diesel Particles and Retrofit Technologies for Diesel Engines, South Coast Air Quality Management District, Nov. 2008.
82) Ayala, A., “California’s approach for mitigating the climate change impacts of high-GWP refrigerants,” Invited Presentation, Fall Industrial Advisory Board Meeting - Air Conditioning and Refrigeration Center, University of Illinois at Urbana-Champaign, 29 - 30 October 2008
81) Shafer, M., Schauer, J., Copan, W., Ayala, A., Hu, S., Herner, J. “Novel Approaches for Speciation of Platinum and Vanadium in Mobile Source Emissions.” 27th AAAR Annual Conference, Rosen Shingle Creek, Orlando, Florida, USA, Oct 20-24, 2008
80) Hu, S., Biswas, S., Verma, V., Schauer, J, Herner,J., Ayala, A. and Sioutas, C., “Chemical Speciation of PM Emissions from Heavy Duty Diesel Vehicles Equipped with Diesel Particulate Filter (DPF) and SCR Retrofits.” 27th AAAR Annual Conference, Rosen Shingle Creek, Orlando, Florida, USA, Oct 20-24, 2008
79) Herner, JD., Shafer, M., Robertson, W., Hu, S., , Collins, J , Huai, T., Schauer, J, Sioutas, C. , and Ayala, A. “Elements Emitted from Advanced Technology Heavy Duty Diesel Vehicles.” 27th AAAR Annual Conference, Rosen Shingle Creek, Orlando, Florida, USA, Oct 20-24, 2008
78) Ayala, A., Hu, S., Herner, J., Chang, M.-C.O., Robertson, W., Collins, J, Huai, T., Rieger, P. and Sioutas, C. “Ionic and Organic Species in PM Emissions from Advanced Technology Heavy Duty Diesel Vehicles.” 27th AAAR Annual Conference, Rosen Shingle Creek, Orlando, Florida, USA, Oct 20-24, 2008
77) Biswas, S., Polidori, A., Verma, V., Hu,S., Herner,J., Ayala, A., Schauer, J, Cho, A., and Sioutas, C. “Toxicity of Particulate Matter from Heavy-Duty Vehicles Retrofitted with Emission Control technologies.” 27th AAAR Annual Conference, Rosen Shingle Creek, Orlando, Florida, USA, Oct 20-24, 2008
76) Ayala, A., “California’s Efforts for Reducing Greenhouse Gas Emissions,” CAPCOA The Future is Green Conference, Long Beach, California, September 2008.
75) Zhan, T., Hsu, Y., Baythavong, B., Gallagher, G., Scheehle, E., Mallory, D., and Ayala, A., “California’s Emissions of High-GWP GHGs and Approaches for Improved Inventory and Verification,” 5th Annual California Climate Change Conference, Sacramento, September 2008.
74) Motallebi, N., Luo, D., and Ayala, A., “Climate Impact Assessment of Carbonaceous Aerosols for California’s Climate Protection Plan,” International Conference of Carbonaceous Particles in the Atmosphere, Lawrence Berkeley National Laboratory, August 2008.
73) Durbin, T.D., Johnson, K.C., Jung, H., Chaudhary, A., Cocker, D.R., Herner, J.D., Robertson, W.H., Huai, T., Ayala, A., and Kittelson, D. “Evaluation of the European PMP Methodologies using chassis dynamometer and on-road testing of heavy-duty vehicles,” Proceedings of the 14th Diesel Engine Emissions Reduction Conference, Detroit, August 2008.
72) Sioutas, C., Biswas, S., Verma, V., Hu, S., Ayala, A., Herner, J., Cho. A., Froines, J.R., Schauer, J., and Cassess, F., “Physicochemical and Toxicological Assessment of Semi-Volatile and Non-volatile PM from Heavy-Duty Vehicles Operating with and without Advanced Emission Control Technologies” Proceedings of the 12th ETH Conference on Combustion Generated Particles, Zurich, SWITZERLAND, June 2008.
71) Ayala, A., “Future Climate Change in California and Greenhouse Gas Mitigation,” 2008 Critical Review Invited Discussion, Air & Waste Management Association, 101st Annual Conference and Exhibit, Portland, June 2008.
70) Zhan, T., Collins, J., Huai, T., Potts, W., Shimer, D., Cicero-Fernandez, P., Ayala, A., Palandre, L., Riachi, Y., Tremoulet, A., and Clodic, D., “Greenhouse Gas Emissions and Abatement Opportunities in Do-it-Yourself Recharging of Leaky Motor Vehicle Air Conditioning Systems in California,” 2008 SAE Alternate Refrigerant System Symposium, Scottsdale, Arizona, June.
69) Ayala, A., “California’s Efforts for Mitigating the Global Climate Impacts of MAC Systems,” 2008 Mobile Air Conditioning Summit, Scottsdale, Arizona, June.
68) Ayala, A., “California’s Efforts for Reducing Greenhouse Gas Emissions,” US-Japan Workshop on Co-Benefits for Climate Actions in Asia, United Nations Conference Center, Bangkok, THAILAND, April 2008.
67) Chang, M., Rieger, P., Herner, J.D., Robertson, W.H., Hu, S., Biswas, S., Verma, V., Huai, T., Fuentes, M., Ayala, A., and Sioutas, C., “CARB’s Phase II Study: Overview of Criteria and Chemistry of Air Toxic Emissions from HD Diesel Vehicles,” Proceedings of the 18th CRC On-Road Vehicle Emissions Workshop, San Diego, CA, March 31-April 2, 2008.
66) Collins, J.F., Huai, T., Ayala, A., Cicero-Fernandez, P., Li, W., Durbin, T.D., Pisano, J.T., Gentala, R., Vescio, N., Full, G., Stove, C., Pasek, R., Saito, D., “Evaluation of High PM Emitting Light-Duty Gasoline Vehicles Using Remote Sensing Devices and Laboratory Dynamometer Testing,” Proceedings of the 18th CRC On-Road Vehicle Emissions Workshop, San Diego, CA, March 31-April 2, 2008.
65) Johnson, K.C., Durbin, T.D., Jung, H., Chaudhary, A., Cocker, D.R., Herner, J.D., Robertson, W.H., Ayala, A., Huai, T., and Kittelson, D., “Evaluation of the European PMP Methodologies Using Chassis Dynamometer and On-road Testing,” Proceedings of the 18th CRC On-Road Vehicle Emissions Workshop, San Diego, CA, March 31-April 2, 2008.
64) Zhang, S., McMahon, W., Wei, Q., Huai, T., and Ayala, A., “Final Results from CARB’s Assessment of the European Reference Vehicle from the Particulate Measurement Programme,” Proceedings of the 18th CRC On-Road Vehicle Emissions Workshop, San Diego, CA, March 31-April 2, 2008.
63) Herner, J.D., Robertson, W.H., Hu, S., Biswas, S., Verma, V., Chang, M., Rieger, P., Huai, T., Fuentes, M., Ayala, A., and Sioutas, C., “Properties of Particles Emitted from Heavy Duty Diesel Vehicles Equipped with NOx and PM Retrofits,” Proceedings of the 18th CRC On-Road Vehicle Emissions Workshop, San Diego, CA, March 31-April 2, 2008.
62) Ayala, A., “The California Approach for Climate Change and Air Quality Protection,” Ministry of Environment of the Republic of Korea – International Workshop on Greenhouse Gas Co-benefits, Seoul, KOREA, February 2008.
61) Ayala, A., Huai, T., Corey, R., “Status Update: California’s Strategies for Motor Vehicle Air Conditioning,” VDA Alternative Refrigerant Winter Meeting, Saalfelden, AUSTRIA, February 2008. Presented by Karen Thundyill, US EPA.
2007
60) Ayala, A., “The Early Actions Plan under California’s AB 32,” Imperial-Mexicali Air Quality Task Force, Calexico, CA, November 15, 2007.
59) Ayala, A., “A brief review of ultrafine particle from IC engines and in ambient air,” CAPCOA Air Toxics and Risk Mangers Committee, Sacramento, Oct 30, 2007.
58) Herner, J.D., Ayala, A., Robertson, W., Chang, O., Biswas, S., and Sioutas, C., “Nucleation Mode Particle Emissions from In-use Heavy Duty Vehicles Equipped with DPF and SCR Retrofits,” American Association for Aerosol Research, Reno, NV, September 18-24, 2007.
57) Herner, J.D., Robertson, W., Ayala, A., Rieger, P., Chang, O., Maddox, C., Ospital, J., Geller, M., and Sioutas, C., “Towards 2010 NOx and PM emission Levels: Overview of CARB’s Investigation of Advanced Heavy-duty On-road Retrofits and Other Technologies,” American Association for Aerosol Research, Reno, NV, September 18-24, 2007.
56) Chang, M.-C. O., Rieger, P., Herner, J.D., Ayala, A., Fuentes, M., Robertson, W., and Sahay, K., “Chemistry of Air Toxics Emitted from In-use Heavy-Duty Vehicles Equipped with SRC Retrofits,” American Association for Aerosol Research, Reno, NV, September 18-24, 2007.
55) Hu, S., Biswas, S., Sioutas, C., Herner, J., Robertson, W., and Ayala, A., “Physical Properties of Particulate Matter (PM) from Heavy Duty Diesel Vehicles Operating with Advanced Emission Control Technologies,” American Association for Aerosol Research, Reno, NV, September 18-24, 2007.
54) Ayala, A., Zhang, S., Herner, J.D., and Robertson, W., “A California Preliminary Assessment of PMP for Determination of Diesel Particle Emissions” Proceedings of the 11th ETH Conference on Combustion Generated Particles, Zurich, SWITZERLAND, August 2007.
53) Herner, J.D., Robertson, W., Ayala, A., and Sioutas, C., “Nanoparticles from a California In-use Truck Equipped with PM-NOx Retrofits” Proceedings of the 11th ETH Conference on Combustion Generated Particles, Zurich, SWITZERLAND, August 2007.
52) Robertson, W.H., Herner, J.D., Ayala, A., and Durbin, T.D., “Investigation of Ultrafine Particle Emissions from Clean Heavy Duty Vehicles using the European PMP Method,” Proceedings of the 13th Diesel Engine Emissions Reduction Conference, Detroit, Aug., 2007.
51) Ayala, A., “Medidas de Inspeccion & Mantenimiento Vehicular para el Control de la Contaminacion del Aire en California, EEUU,” 6to Congreso Regional de la IV Region de la Asociacion Argentina de Ingenieria Sanitaria y Ciencias del Ambiente, Seminario Internacional: Eficiencia Energetica y Emisiones Contaminantes en el Sector Autotransporte, Buenos Aires, ARGENTINA, Julio 25 – 27, 2007.
50) Ayala, A., “Imprementacion de tecnlogias automotrices limpias en California y su proyeccion internacional,” 6to Congreso Regional de la IV Region de la Asociacion Argentina de Ingenieria Sanitaria y Ciencias del Ambiente, Seminario Internacional: Eficiencia Energetica y Emisiones Contaminantes en el Sector Autotransporte, Buenos Aires, ARGENTINA, Julio 25 – 27, 2007.
49) Ayala, A. and Huai, T., “The California Approach to Emission Reduction from Motor Vehicles,” International Conference on Transport and Environment: A global challenge, Technical and Policy Solutions, Milan, ITALY, March 19 – 21, 2007.
48) Ayala, A., Huai, T., Maldonado, H., and Chernich, D., “California ARB Regulatory Overview and Experience with PEMS,” International Conference on Transport and Environment: A global challenge, Technical and Policy Solutions, Milan, ITALY, March 19 – 21, 2007.
47) Ayala, A., Herner, J.D., Zhang, S., Robertson, W., Frodin, B., Huai, T., Haste, R., McMahan, W., and Lemieux, S., ‘Experiences from the CARB PMP-based Program,” International Conference on Transport and Environment: A global challenge, Technical and Policy Solutions, Milan, ITALY, March 19 – 21, 2007.
46) Herner, J.D., Zhang, S., Frodi, B., Leeman, W., Ayala, A., Johnson, T., and Wei, Q., “Emissions Measurements from the Golden Vehicle – A Light Duty Diesel Vehicle Used During Validation of the European PMP Protocol” Proceedings of the 17th CRC On-Road Vehicle Emissions Workshop, San Diego, CA, March 26-28, 2007.
45) Herner, J.D., Kozawa, K., Fruin, S., Huai, T., Leeman, W., Ayala, A., Winer, A., Krudysz, M., and Houston, D., “On road measurements of particle size distributions using a mobile platform – Nucleation and effect of recent introduction of ULSD,” Proceedings of the 17th CRC On-Road Vehicle Emissions Workshop, San Diego, CA, March 26-28, 2007.
44) Huai, T., Collins, J.F., Ayala, A., Durbin, T.D., Li, W., Full, G., Mazzoleni, C., Nussbaum, N.J., Obrist, D., Zhu, D., Kuhns, H.D., and Moosm?ller, H., “Comparison of Remote Sensing Devices with Gravimetric Measurements of Light-duty Gasoline PM Emissions,” Proceedings of the 17th CRC On-Road Vehicle Emissions Workshop, San Diego, CA, March 26-28, 2007.
43) Collins, J.F., Huai, T., Ayala, A., Durbin, T.D., Li, W., Sulik, C., and Pasek, R., “Evaluation of Real-Time Measurment Methods to Detect and Characterize PM Emissions from High-Emitting Light-Duty Gasoline Vehicles,” Proceedings of the 17th CRC On-Road Vehicle Emissions Workshop, San Diego, CA, March 26-28, 2007.
2006
42) Ayala, A. and Herner, J.D., “Characterization of Combustion-generated Ultrafine Particles from Mobile Sources,” 1st California Electricity and Air Quality Conference, California Energy Commission, Sacramento, Oct. 3 -4-, 2006.
41) Herner, J.D. and Ayala, A. “Effect of Dilution Method and a Diesel Particle Filter on Ultrafine and Nucleation Mode Particle Formation in the Exhaust from a Newer Medium Heavy Duty Diesel Truck Tested on a Chassis Dynamometer,” 2006 International Aerosol Conference, American Association for Aerosol Research, St. Paul, MN, September 10-15, 2006.
40) Ayala, A., “Las Emisiones y su Impacto en la Calidad del Aire,” Seminario-Taller Internacional Sobre Experiencia en Manejo de la Calidad del Aire Urbano, Guayaquil, ECUADOR, Agosto 31 – Septiembre 1, 2006.
39) Ayala, A., “Control de Emisiones: Experiencias de California en el Desarrollo de Estrategias y el Uso de Tecnología Avanzada,” Seminario-Taller Internacional Sobre Experiencia en Manejo de la Calidad del Aire Urbano, Guayaquil, ECUADOR, Agosto 31 – Septiembre 1, 2006.
38) Ayala, A., Herner, J., and Huai, T., “California’s Efforts for Advancing Ultrafine Particle Number Measurements for Clean Diesel Exhaust,” Proceedings of the 12th Diesel Engine Emissions Reduction Conference, Detroit, Michigan, Aug., 2006.
37) Ayala, A., Hughes, P., Corey, R., and Church S., “CO2 Emission Quantification from Vehicle Air Conditioning Operation in California-Specific Conditions,” Society of Automotive Engineers 7th Alternate Refrigerant Systems Symposium, Scottsdale, AZ, June 27-29, 2006.
36) Vincent, R., Ayala, A., and Corey R., “New Proposed HFC Reduction Measures for California,” Society of Automotive Engineers 7th Alternate Refrigerant Systems Symposium, Scottsdale, Arizona, June 27-29, 2006.
35) Ayala, A., “Methods and Characterization of Ultrafine Particles In Various Engine Exhaust Aerosols,” International Conference on Ultrafine Particles: The Science, Technology, and Policy Issues, South Coast Air Quality Management District, Los Angeles, CA, April 30 – May 2, 2006
34) Ayala, A., “PEMSs and CARB: Overview of Activities,” Semtech® User Network (SUN) Spring Conference
on In-Use Vehicle Emissions Testing, March 31, 2006 San Diego, California
33) Herner, J. and Ayala, A., “Evaluation of Ultrafine Particle Measurement Instruments and the European PMP Protocol on a California Trap-equipped Diesel Truck,” Proceedings of the 16th CRC On-Road Vehicle Emissions Workshop, San Diego, CA, March 28-30, 2006.
32) Huai, T., Smallwood, G.J., Ayala, A., Bachalo, W.D., Payne, G., Witze, P., Johnson, K., and Maldonado, H., “Comparison of Particulate Matter Emission Measurements By Laser-induced Incandescence to the Gravimetric Procedure,” Proceedings of the 16th CRC On-Road Vehicle Emissions Workshop, San Diego, CA, March 28-30, 2006.
31) Ayala, A. and Church, S. “Reducing Vehicle Refrigerant Emissions as an Important Strategy in California’s Climate Change Protection Plan,” 2006 Mobile Air Conditioning Summit, Saalfelden, AUSTRIA, February 17, 2006.
2005
30) Ayala, A., “Diesel Emissions: Overview of Regulatory and Research Efforts,” Invited Seminar, Fall Seminar Series, Mechanical and Aeronautical Engineering, University of California, Davis, Nov. 2005.
29) Ayala, A., “Emission Control Technologies,” 7th Annual UC Davis Conference for Environmental Health Scientists. Air Toxics in Central California. Napa, CA, August 29, 2005.
28) Andreoni, T. and Ayala, A., “Diesel Emission Control Technology Developments,” Proceedings of the 11th Diesel Engine Emissions Reduction Conference, Chicago, August 2005.
27) Ayala, A. and Herner, J., “California’s Efforts for Advancing Combustion-generated Ultrafine Particle Research,” Proceedings of the 9th ETH Conference on Combustion Generated Particles, Zurich, SWITZERLAND, August 2005.
26) Fruin, S., Westerdahl, D., Kozawa, K., Herner, J. and Ayala, A., “In-Vehicle Exposure Research in California,” Proceedings of the 9th ETH Conference on Combustion Generated Particles, Zurich, SWITZERLAND, August 2005.
25) Ayala, A., “Hilights from CARB’s Research Programs in Emission Control,” 68th Meeting of the Petroleum Environmental Research Forum. Palo Alto, CA, July 27, 2005.
24) Nanzetta-Converse, M.K., B.A. Holmen, and A. Ayala, “Size-selective Measurements of Ultrafine Particle Emissions from a CNG and a Trap-equipped Diesel Bus During Transient Operation,” Proceedings of the 15th CRC On-Road Vehicle Emissions Workshop, San Diego, CA, April 4–7, 2005.
23) Johnson, K., Shah, S., Miller, W., Chernich, D., Ayala, A., and Maldonado, H., “Correlation of a Partial-Flow Diluter to the Full-Flow CVS for Determination of Heavy-Duty Vehicle Emissions under Steady-State Operation,” Proceedings of the 15th CRC On-Road Vehicle Emissions Workshop, San Diego, CA, April 4–7, 2005.
22) Ayala, A., Sahay, K., Karim, J., and Rodas, R., “Transient Ultrafine Particle Emission Measurements with a New Fast Aerosol Sizer,” Proceedings of the 15th CRC On-Road Vehicle Emissions Workshop, San Diego, CA, April 4–7, 2005.
21) Cleary, K.W., Ayala, A., Harley, R.A., and Gebel, M.E., “Pilot Study of Direct Emissions of HFC-134a Mobile Refrigerant from a California Traffic Tunnel,” Proceedings of the 15th CRC On-Road Vehicle Emissions Workshop, San Diego, CA, April 4–7, 2005.
20) Berard, L. and Ayala, A. “Treatment of Vehicle Air Conditioning Systems in CARB’s Greenhouse Gas Regulation,” 2005 Mobile Air Conditioning Summit, Sacramento, CA, March 15-16, 2005.
19) Ayala, A., “Climate Change Emissions: California’s Efforts and the Role of Superior MACS,” Workshop on Technology Cooperation for Next-Generation Mobile Air Conditioning, New Delhi, INDIA, March 3-4, 2005.
2004
18) Ayala, A. and Gautam, M., “Particulate Matter Research Progress in the US and California,” Proceedings of the 8th ETH Conference on Combustion Generated Particles, Zurich, SWITZERLAND, August 2004.
17) Ayala, A., “Emisiones Vehiculares y Calidad del Aire: Avances, Retos y Perspectivas,” Seminario Internacional, La Calidad del Aire: Responsabilidad de Todos, Quito, ECUADOR, Agosto 3 - 7, 2004.
2003
16) Kado, N.Y., Ayala, A., and Okamoto, R.A., “Size-segregated PM Emissions from Diesel with After-treatment and from CNG-fueled Transit Buses,” Annual Conference of the American Association for Aerosol Research, Anaheim, CA, October 20-24, 2003.
15) Kado, N.Y., Okamoto, R.A., Kuzmicky, P.A., Kobayashi, R., Ayala, A., Gebel, M.E., Rieger, P.L., Maddox, C., and Zafonte, L., “Emissions of Toxic Pollutants from Compressed Natural Gas and Ultra-low Sulfur Diesel Fueled Transit Buses with and without After-treatment Devices,” Annual Conference of the American Association for Aerosol Research, Anaheim, CA, October 20-24, 2003.
14) Ayala, A., Kado, N., Okamoto, R., Gebel, M., Rieger, P., Kobayashi, R., and Kuzmicky, P., “CNG and Diesel Transit Bus Emissions in Review,” Proceedings of the 9th Diesel Engine Emissions Reduction Conference, Newport, RI, Aug., 2003.
13) Ayala, A., Kado, N.Y., Okamoto, R.A., Kuzmicky, P.A., and Kobayashi, R., “CNG and Diesel Transit Bus Emissions in Review,” Proceedings of the 7th ETH Conference on Combustion Generated Particles, Zurich, SWITZERLAND, August 2003.
12) Ayala, A., M.E. Gebel, R.A. Okamoto, P.L. Rieger, N.Y. Kado, C. Cotter, and N. Verma, “Oxidation Catalyst Effect on CNG Transit Bus Emissions,” Proceedings of the 13th CRC On-Road Vehicle Emissions Workshop, San Diego, CA, April 7–9, 2003.
11) Ayala, A. and B.A. Holmen, “Comparison of Particle Size Distributions for Diesel and CNG Transit Buses with After-treatment,” Proceedings of the 13th CRC On-Road Vehicle Emissions Workshop, San Diego, CA, April 7–9, 2003.
10) Ayala, A., N.Y. Kado, R.A. Okamoto, M.E. Gebel, P.L. RiegerP.A. Kuzmicky, and R. Kobayashi, “Comparison of Emissions from Two Diesel and CNG Buses with After-treatment,” 4th World Truck Conference, Monterey, California, March 2 – 4, 2003.
2002
9) Holmen, B.A. and A. Ayala, “Natural Gas Transit Bus Ultrafine Particle Emissions: Laboratory Dilution and Number Distributions,” Annual Conference of the American Association for Aerosol Research, Charlotte, NC, October 7-11, 2002.
8) Ayala, A., N. Kado, R. Okamoto, M. Gebel, P. Rieger, and B.A. Holmen, “ARB’s Study of Emissions from Diesel and CNG Heavy-duty Transit Buses,” Proceedings of the 8th Diesel Engine Emissions Reduction Conference, San Diesel, CA, August 2002.
7) Holmen, B.A. and A. Ayala, “Oxidation Catalyst Effect on Natural Gas Transit Bus Ultrafine Particle Emissions,” Proceedings of the 6th ETH Conference on Nanoparticle Measurements, Zurich, SWITZERLAND, August 2002.
6) Ayala, A., N.Y. Kado, R.A. Okamoto, B.A. Holmen, and K.E. Stiglitz, “Comparative Study of Diesel and CNG Heavy-Duty Transport Bus Emissions,” Proceedings of the 12th CRC On-Road Vehicle Emissions Workshop, San Diego, CA, April 2002.
5) Ayala, A., “Overview of ARB’s Vehicle Emissions Research and Related Activities,” 5th Workshop on Mexico City Air Quality, January 21-24, 2002, Ixtapan de la Sal, MEXICO.
2001
4) Holmen, B.A., A. Ayala, N. Kado, and R. Okamoto, “ARB’s Study of Emissions from “Late-model” Diesel and CNG Heavy-duty Transit Buses: Preliminary Nanoparticle Measurement Results,” Proceedings of the 5th ETH Conference on Nanoparticle Measurements, Zurich, SWITZERLAND, August 2001.
3) Ayala, A. and Olson, B., “In-situ Diffusion Loss Measurements as Part of Quality Assurance in Diesel Aerosol Research,” Proceedings of the 11th Coordinating Research Council Workshop, San Diego, CA, March 2001.
2) Younglove, T., A. Ayala, T.D. Durbin, S. Kidd, C. Malcolm, M.R. Smith, and J. Gaskins, “Overview and Results of a Statewide Survey of Vehicle Registration Status in California,” Proceedings of the 11th Coordinating Research Council Workshop, San Diego, CA, March 2001.
2000
1) Gautam, M., Zhuyun, X., Ayala, A., and Mehta, S., “Diesel Exhaust Plume Studies: Wind Tunnel Experiments and Modeling,” Proceedings of the 4th ETH Conference on Nanoparticle Measurements, Zurich, SWITZERLAND, August 2000.